FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Yamamoto, Y Friedman, H Yoshimura, H Shioda, S Debari, K Shinohara, K Richardson, M Denbeaux, G AF Yamamoto, Y Friedman, H Yoshimura, H Shioda, S Debari, K Shinohara, K Richardson, M Denbeaux, G TI Fine hydrophilic cell surface structures of macrophages in medium can be analyzed by x-ray microscopy. SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ S Florida, Coll Med, Dept Med Microbiol Immunol, Tampa, FL 33612 USA. Meiji Univ, Sch Sci & Technol, Tokyo 101, Japan. Showa Univ, Sch Med, Tokyo 142, Japan. Univ Tokyo, Tokyo, Japan. Univ Cent Florida, Orlando, FL 32816 USA. Ernest Orlando Lawence Berkeley Natl Lab, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 7 PY 2001 VL 15 IS 4 BP A382 EP A382 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 410KA UT WOS:000167438102188 ER PT J AU Powell, KR McCleskey, TM Tumas, W DeSimone, JM AF Powell, KR McCleskey, TM Tumas, W DeSimone, JM TI Polymers with multiple ligand sites for metal extractions in dense-phase carbon dioxide SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID SUPERCRITICAL-FLUID EXTRACTION; CO2-SOLUBLE CHELATING-AGENTS; FLUORINATED BETA-DIKETONES; TRIBUTYL-PHOSPHATE; ORGANOPHOSPHORUS REAGENTS; AQUEOUS-SOLUTIONS; HEAVY-METALS; CO2; LIQUID; CATALYSIS AB We have synthesized a series of CO2-soluble polymeric extractants with multiple ligand sites for CO2-based metal extractions. The CO2-soluble polymers were prepared via free-radical copolymerization of a fluorinated acrylate with a series of acrylate- or styrene-based monomers functionalized with ligand sites or ligand precursors. These polymers have high solubility in CO2; up to 30 wt % of a polymer with 15 mol % of a ligand-based monomer can be solubilized in liquid CO2 at 25 degreesC at 140 bar. Copper and europium extractions have been performed with beta -diketone- and phosphonate-functionalized polymers, respectively. Preliminary extractions with copper nitrate were carried out at ligand-to-metal ratios of 1:1 and 2.7:1, resulting in 25-37% and 59% efficiency, respectively, suggesting a ligand binding stoichiometry of 2 for efficient extraction. Europium luminescence studies demonstrate that. europium is bound to the polymer along with four water molecules in the inner coordination sphere. C1 Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. Univ Calif Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP McCleskey, TM (reprint author), Univ N Carolina, Dept Chem, CB 3290, Chapel Hill, NC 27599 USA. RI McCleskey, Thomas/J-4772-2012; OI Mccleskey, Thomas/0000-0003-3750-3245 NR 38 TC 19 Z9 19 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAR 7 PY 2001 VL 40 IS 5 BP 1301 EP 1305 DI 10.1021/ie000811b PG 5 WC Engineering, Chemical SC Engineering GA 406PN UT WOS:000167224500002 ER PT J AU Rutherford, SW AF Rutherford, SW TI Mechanism of sorption and diffusion in a high free-volume polymer SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID CARBON MOLECULAR-SIEVE; SURFACE-DIFFUSION; MULTILAYER ADSORPTION; GAS-PERMEABILITY; PERMEATION; TRANSPORT; POLY<1-(TRIMETHYLSILYL)-1-PROPYNE>; POLY(1-TRIMETHYLSILYL-1-PROPYNE) AB The structure of poly[1-(trimethylsilyl)-1-propyne] (PTMSP) is distinct from other glassy polymers because of the presence of bulky side groups which obstruct the packing of polymer chains and allow extraordinarily high permeability of sorbed molecules. Molecular transport models traditionally applied to standard glassy polymers reach some limitations in the description of diffusion in PTMSP because of differences in the mechanism of sorption and diffusion. Analysis of sorption equilibria and permeability data measured for PTMSP is undertaken in an effort to elucidate the mechanism of mass transfer. Sorption equilibrium indicates that a multilayer adsorption mechanism can account for the isotherm data, and analysis of dynamics indicates that a multilayer surface diffusion model successfully characterizes the permeability measurement. A favorable comparison of values for the characterizing variables between PTMSP and other microporous materials generates further support for the assertion that this high free-volume glassy polymer can also be viewed as a microporous material. C1 Univ Calif Los Alamos Natl Lab, Engn Sci & Applicat Div, Los Alamos, NM 87545 USA. RP Rutherford, SW (reprint author), Univ Calif Los Alamos Natl Lab, Engn Sci & Applicat Div, MS C930, Los Alamos, NM 87545 USA. NR 27 TC 14 Z9 14 U1 0 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAR 7 PY 2001 VL 40 IS 5 BP 1370 EP 1376 DI 10.1021/ie000760i PG 7 WC Engineering, Chemical SC Engineering GA 406PN UT WOS:000167224500011 ER PT J AU Muske, KR Littell, JD Dell'Orco, PC Le, LA Flesner, RL AF Muske, KR Littell, JD Dell'Orco, PC Le, LA Flesner, RL TI Hydrothermal treatment of C-N-O-H wastes: Model-based reactor effluent control SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID SUPERCRITICAL WATER; CHEMICAL PROCESSES; FEEDBACK-CONTROL; THERMODYNAMICS; ELECTROLYTES AB In this work, we present model-based control and estimation algorithms developed to control the effluent composition for a hydrothermal oxidation reactor. The reactor is used to oxidize the organic compounds present in the hydrolysate solutions obtained from the destruction of HMX-based high explosives by base hydrolysis. The objective of the model-based control is to minimize the total amount of aqueous nitrogen compounds in the effluent of the reactor while maintaining the desired excess oxygen concentration in the reactor to ensure the complete destruction of the organic carbon compounds. A novel aspect of the controller design for this reactor is that the total aqueous nitrogen effluent concentration is locally uncontrollable at the desired optimal operating conditions. The controller uses a plug-flow reactor model with a reduced kinetic model describing the oxidation-reduction reactions in the hydrothermal oxidation reactor. Simulation and reactor implementation results are used to verify the closed-loop control algorithm. C1 Villanova Univ, Dept Chem Engn, Villanova, PA 19085 USA. Los Alamos Natl Lab, High Explos Sci & Technol Grp, Los Alamos, NM 87545 USA. RP Villanova Univ, Dept Chem Engn, Villanova, PA 19085 USA. EM krmuske@kayak.che.vill.edu NR 19 TC 7 Z9 7 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAR 7 PY 2001 VL 40 IS 5 BP 1397 EP 1405 DI 10.1021/ie000660c PG 9 WC Engineering, Chemical SC Engineering GA 406PN UT WOS:000167224500014 ER PT J AU Lewis, LH Moodenbaugh, AR Welch, DO Panchanathan, V AF Lewis, LH Moodenbaugh, AR Welch, DO Panchanathan, V TI Stress, strain and technical magnetic properties in 'exchange-spring' Nd2Fe14B+alpha-Fe nanocomposite magnets SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID ND-FE-B; CURIE-TEMPERATURE; ALLOYS; ENHANCEMENT; ND2FE14B AB A modified Williamson-Hall analysis was applied to synchrotron transmission x-ray diffraction data obtained for a series of three melt-spun magnetic nanocomposite 'exchange-spring' materials comprised of Nd2Fe14B and varying amounts of alpha -Fe ranging from 0-32 vol%. Analysis of the data demonstrates that there is no measureable contribution from microstrains or other lattice distortions in the Nd2Fe14B phase. This result: indicates that the Nd2Fe14B Bragg peak broadening arises from particle size only ton the order of 440 Angstrom and that the shape of the melt-quenched Nd2Fe14B grains is approximately spherical. In contrast, the alpha -Fe phase exhibits Bragg peak broadening that may be attributed to a combination of both anisotropic strain and particle-size broadening effects.. The average particle size of the alpha -Fe phase is 360 Angstrom, significantly larger than that determined from the Scherrer formula, and the average stress, deduced to be tensile, of the alpha -Fe particles is approximately 1 GPa, which translates to an rms strain (e) over tilde = [e(2)](1/2) of approximately 0.1%. These results provide a physical basis to explain both the marginal exchange-derived remanence enhancement and the anomalous elevated-temperature coercivities found in these alloys. C1 Brookhaven Natl Lab, Dept Energy Sci & Technol, Div Mat & Chem Sci, Upton, NY 11973 USA. MQI, Anderson, IN 46013 USA. RP Brookhaven Natl Lab, Dept Energy Sci & Technol, Div Mat & Chem Sci, Upton, NY 11973 USA. OI Moodenbaugh, Arnold/0000-0002-3415-6762 NR 34 TC 26 Z9 26 U1 1 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 EI 1361-6463 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD MAR 7 PY 2001 VL 34 IS 5 BP 744 EP 751 DI 10.1088/0022-3727/34/5/313 PG 8 WC Physics, Applied SC Physics GA 417LD UT WOS:000167835700015 ER PT J AU Friderichsen, AV Radziszewski, JG Nimlos, MR Winter, PR Dayton, DC David, DE Ellison, GB AF Friderichsen, AV Radziszewski, JG Nimlos, MR Winter, PR Dayton, DC David, DE Ellison, GB TI The infrared spectrum of the matrix-isolated phenyl radical SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ULTRAVIOLET PHOTOELECTRON-SPECTROSCOPY; GAS-PHASE; ABSORPTION SPECTROSCOPY; SUPERSONIC JET; RATE-CONSTANT; ORIGIN BAND; KINETICS; ARGON; MASS; BENZENE AB We have measured the infrared absorption spectrum of C6H5, (X) over tilde (2)A(1), in an Ar matrix at 10 K. The experimental frequencies (cm(-1)) and polarizations follow, a(1) modes: 3086; 3072, 3037, 1581, 1441, 1154, 1027, 997, 976, 605;b(1) modes: 972, 874, 706, 657, 416; b(2) modes: 3071, 3069, 1624, 1432, 1321, 1283, 1 159, 1063, and 587. Three different methods have been used for the production of the phenyl radicals. Infrared absorption spectra of five deuterated isotopomers, C6D5, p-C6H4D, p-C6HD4, o-C6H4D, and m-C6H4D, were recorded to compare experimental frequency shifts with calculated (UB3LYP/cc-pVDZ) harmonic frequency shifts. The use of CO2 or NO as internal standards enabled the experimental determination of absolute infrared intensities. The linear dichroism was measured with photooriented samples to establish experimental polarizations of each vibrational band. True gas-phase vibrational frequencies were estimated by considering the gas-to-matrix shifts and matrix;inhomogeneous line broadening. The phenyl radical matrix frequencies listed above are within +/-1% of the gas-phase vibrational frequencies. The C6H5 frequencies from this paper supersede our earlier values reported in J. Am. Chem. Soc. 1996, 118, 7400-7401. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. Univ Colorado, CIRES, Integrated Instrument Design Facil, Boulder, CO 80309 USA. Colorado Sch Mines, Dept Chem Engn & Petr Refining, Golden, CO 80401 USA. RP Radziszewski, JG (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 74 TC 75 Z9 76 U1 5 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAR 7 PY 2001 VL 123 IS 9 BP 1977 EP 1988 DI 10.1021/ja0024338 PG 12 WC Chemistry, Multidisciplinary SC Chemistry GA 407CE UT WOS:000167253200024 PM 11456819 ER PT J AU Kadkhodayan, S Coin, F Salazar, EP George, JW Egly, JM Thompson, LH AF Kadkhodayan, S Coin, F Salazar, EP George, JW Egly, JM Thompson, LH TI Codominance associated with overexpression of certain XPD mutations SO MUTATION RESEARCH-DNA REPAIR LA English DT Article DE xeroderma pigmentosum; trichothiodystrophy; XPD mutations; nucleotide-excision repair ID NUCLEOTIDE EXCISION-REPAIR; RNA-POLYMERASE-II; TRANSCRIPTION FACTOR IIH; CHINESE-HAMSTER CELLS; ERCC2 DNA-REPAIR; XERODERMA-PIGMENTOSUM; COCKAYNE-SYNDROME; MOLECULAR CHARACTERIZATION; REPAIR/TRANSCRIPTION GENE; SACCHAROMYCES-CEREVISIAE AB Mutations in the XPD gene are associated with three complex clinical phenotypes, namely xeroderma pigmentosum (XP), XP in combination with Cockayne syndrome (XP-CS), and trichothiodystrophy (TTD). XP is caused by a deficiency in nucleotide excision repair (NER) that results in a high risk of skin cancer. TTD is characterized by severe developmental and neurological defects, with hallmark features of brittle hair and scaly skin, and sometimes has defective NER. We used CHO cells as a system to study how specific mutations alter the dominant/recessive behavior of XPD protein. Previously we identified the T46I and R75W mutations in two highly UV-sensitive hamster cell lines that were reported to have paradoxically high levels of unscheduled DNA synthesis, Here we report that these mutants have greatly reduced XPD helicase activity and fully defective NER in a cell-extract excision assay. We conclude that the unscheduled DNA synthesis seen in these mutants is caused by abortive "repair" that does not contribute to cell survival. These mutations, as well as the K48R canonical helicase-domain mutation, each produced codominant negative phenotypes when overexpressed in wild-type CHO cells. The common XP-specific R683W mutation also behaved in a codominant manner when overexpressed, which is consistent with the idea that this mutation may affect primarily the enzymatic activity of the protein rather than impairing protein interactions, which may underlie TTD. A C-terminal mutation uniquely found in TTD (R722W) was overexpressed but not to levels sufficiently high to rigorously test for a codominant phenotype. Overexpression of mutant XPD alleles may provide a simple means of producing NER deficiency in other cell lines. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. ULP, INSERM, CNRS, Inst Genet & Biol Mol & Cellulaire, F-67404 Illkirch, CU De Strasbour, France. RP Thompson, LH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, L441,POB 808, Livermore, CA 94551 USA. RI Coin, Frederic/F-5925-2013 FU NCI NIH HHS [CA52679] NR 77 TC 4 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8777 J9 MUTAT RES-DNA REPAIR JI Mutat. Res.-DNA Repair PD MAR 7 PY 2001 VL 485 IS 2 BP 153 EP 168 DI 10.1016/S0921-8777(00)00077-X PG 16 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 404ZD UT WOS:000167132000006 PM 11182546 ER PT J AU Bogen, KT Enns, L Hall, LC Keating, GA Weinfeld, M Murphy, G Wu, RW Panteleakos, FN AF Bogen, KT Enns, L Hall, LC Keating, GA Weinfeld, M Murphy, G Wu, RW Panteleakos, FN TI Gel microdrop flow cytometry assay for low-dose studies of chemical and radiation cytotoxicity SO TOXICOLOGY LA English DT Article DE assay; cell killing; chemical mutagen; flow; low-dose; low-LET radiation; microdrop; survival ID CELLS; MODEL AB Low-level cytotoxicity may affect low-dose dose-response relations for cancer and other endpoints. Conventional colony-forming assays are rarely sensitive enough to examine small changes in cell survival and growth. Automated image-analysis techniques are limited to ca. 104 cells/plate. An alternative method involves encapsulation of single proliferating cells into ca. 35-75-mum-diameter agarose gel microdrops (GMDs) that are randomly grouped, differential exposure of these groups, culture at 37 degreesC for 3-5 days, and finally GMD analysis by flow cytometry (FC) to determine the ratio of GMDs containing multiple versus single cells as a measure of clonogenic survival. This GMD/FC assay was used to examine low-dose cell killing induced by a cooked-meat mutagen/rodent-carcinogen (MeIQx) in DNA-rep air-deficient/metabolically-sensitive CHO cells. Results of conventional colony-forming as says using up to 30 replicate plates indicate a shouldered, threshold-like dose-response:, in contrast; those obtained using the GMD/FC assay suggest 'hypersensitivity'-like nonlinearity in dose-response. The GMD/FC assay was also applied to human A549 lung cells after GMD-encapsulation and gamma radiation followed by culture for a total of 4 days, to examine survival after exposure to greater than or equal to 100 cGy delivered at a relatively low dose rate (0.18 cGy/min). Dose-response for clonogenic growth was again observed to be reduced with apparent nonlinear suggesting hypersensitivity between 0 and 50 cGy, insofar as doses of 5 and 10 cGy appear to be ca. fivefold more effective per unit dose than the 50- or 100-cGy doses used. The GMD/FC assay may thus reveal low-dose dose-response relations for chemical and radiation effects on cell proliferation/killing with implications for low-dose risk assessment. (C) 2001 Published by Elsevier Science Ireland Ltd. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div L396, Livermore, CA 94550 USA. Cross Canc Inst, Edmonton, AB T6G 1Z2, Canada. RP Bogen, KT (reprint author), Univ Calif Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div L396, 7000 East Ave, Livermore, CA 94550 USA. FU NCI NIH HHS [P01 CA55861-01] NR 16 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0300-483X J9 TOXICOLOGY JI Toxicology PD MAR 7 PY 2001 VL 160 IS 1-3 SI SI BP 5 EP 10 DI 10.1016/S0300-483X(00)00432-7 PG 6 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA 414WH UT WOS:000167688800002 PM 11246118 ER PT J AU Lehnert, NM Gary, RK Marrone, BL Lehnert, BE AF Lehnert, NM Gary, RK Marrone, BL Lehnert, BE TI Inhibition of normal human lung fibroblast growth by beryllium SO TOXICOLOGY LA English DT Article DE beryllium; lung fibroblasts; cell growth; cell cycle; TP53; CDKN1A ID CYCLIN-DEPENDENT KINASES; CELL-CYCLE; ALPHA-PARTICLES; CDK INHIBITORS; G(1) ARREST; PROLIFERATION; CHECKPOINTS; INDUCTION; DISEASE; P53 AB Inhalation of particulate beryllium (Be) and its compounds causes chronic Be disease (CBD) in a relatively small subset (similar to 1-6%) of exposed individuals. Hallmarks of this pulmonary disease include increases in several cell types, including lung fibroblasts, that contribute to the fibrotic component of the disorder. In this regard, enhancements in cell proliferation appear to play a fundamental role in CBD development and progression. Paradoxically, however, some existing evidence suggests that Be actually has antiproliferative effects. In order to gain further information about the effects of Be on cell growth, we: (1) assessed cell proliferation and cell cycle effects of low concentrations of Be in normal human diploid fibroblasts, and (2) investigated the molecular pathway(s) by which the cell cycle disturbing effects of Be may be mediated. Treatment of human lung and skin fibroblasts with Be added in the soluble form of BeSO4 (0.1-100 muM) caused inhibitions of their growth in culture in a concentration-dependent manner. Such growth inhibition was found to persist, even after cells were further cultured in Be2+-free medium. Flow cytometric analyses of cellular DNA labeled with the DNA-binding fluorochrome DAPI revealed that Be causes a G(0)-G(1)/pre-S phase arrest. Western blot analyses indicated that the Be-induced G(0)-G(1)/pre-S phase arrest involves elevations in TP53 (p53) and the cyclin-dependent kinase inhibitor CDKN1A (p21(Waf-1,Cip1)). That Be at low concentrations inhibits the growth of normal human fibroblasts suggests the possibility of the existence of abnormal cell cycle inhibitory responses to Be in individuals who are sensitive to the metal and ultimately develop CBD. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. RP Lehnert, BE (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, MS M888, Los Alamos, NM 87545 USA. RI Gary, Ronald/A-8650-2008 OI Gary, Ronald/0000-0001-5079-1953 NR 34 TC 16 Z9 17 U1 0 U2 0 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0300-483X J9 TOXICOLOGY JI Toxicology PD MAR 7 PY 2001 VL 160 IS 1-3 SI SI BP 119 EP 127 DI 10.1016/S0300-483X(00)00439-X PG 9 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA 414WH UT WOS:000167688800016 PM 11246132 ER PT J AU Dong, J Peters-Libeu, CA Weisgraber, KH Segelke, BW Rupp, B Capila, I Hernaiz, MJ LeBrun, LA Linhardt, RJ AF Dong, J Peters-Libeu, CA Weisgraber, KH Segelke, BW Rupp, B Capila, I Hernaiz, MJ LeBrun, LA Linhardt, RJ TI Interaction of the N-terminal domain of apolipoprotein E4 with heparin SO BIOCHEMISTRY LA English DT Article ID LDL RECEPTOR-BINDING; III HYPERLIPOPROTEINEMIA; SOLUTION CONFORMATION; ALZHEIMERS-DISEASE; AQUEOUS-SOLUTION; OLIGOSACCHARIDES; SEQUENCE; PROTEIN; ALLELE; GLYCOSAMINOGLYCANS AB Apolipoprotein E (apoE) is an important lipid-transport protein in human plasma and brain. It has three common isoforms (apoE2, apoE3, and apoE4), ApoE is a major genetic risk factor in heart disease and in neurodegenerative disease, including Alzheimer's disease. The interaction of apoE with heparan sulfate proteoglycans plays an important role in lipoprotein remnant uptake and likely in atherogenesis and Alzheimer's disease, Here we report our studies of the interaction of the N-terminal domain of apoE4 (residues 1-191), which contains the major heparin-binding site, with an enzymatically prepared heparin oligosaccharide. Identified by its high affinity for the N-terminal domain of apoE4, this oligosaccharide was determined to be an octasaccharide of the structure Delta UAp2S(1-->[4)-alpha -D-GlcNpS6S(1-->4)-alpha -L-IdoAp2S(1-->](3)4)-alpha -D-GlcNpS6S by nuclear magnetic resonance spectroscopy, capillary electrophoresis, and polyacrylamide gel electrophoresis. Kinetic analysis of the interaction between the N-terminal apoE4 fragment and immobilized heparin by surface plasmon resonance yielded a K-d of 150 nM. A similar binding constant (K-d = 140 nM) was observed for the interaction between immobilized N-terminal apoE4 and the octasaccharide. Isothermal titration calorimetry revealed a K-d of 75 nM for the interaction of the N-terminal apoE fragment and the octasaccharide with a binding stoichiometry of approximately 1:1. Using previous studies and molecular modeling, we propose a binding site for this octasaccharide in a basic residue-rich region of helix 4 of the N-terminal fragment. From the X-ray crystal structure of the N-terminal apoE4, we predicted that binding of the octasaccharide at this site would result in a change in intrinsic fluorescence. This prediction was confirmed experimentally by an observed increase in fluorescence intensity with octasaccharide binding corresponding to a K-d of similar to1 muM. C1 Univ Iowa, Dept Chem, Iowa City, IA 52242 USA. Univ Calif San Francisco, Gladstone Inst Cardiovasc Dis, Cardiovasc Res Inst, San Francisco, CA 94941 USA. Univ Calif San Francisco, Dept Pathol, San Francisco, CA 94941 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Univ Iowa, Dept Med, Iowa City, IA 52242 USA. Univ Iowa, Dept Nat Prod Chem, Iowa City, IA 52242 USA. Univ Iowa, Dept Chem & Biochem Engn, Iowa City, IA 52242 USA. RP Linhardt, RJ (reprint author), Univ Iowa, Dept Chem, Iowa City, IA 52242 USA. FU NHLBI NIH HHS [HL 41633, HL 52622]; NIGMS NIH HHS [GM 38060]; NINDS NIH HHS [NS 35939] NR 47 TC 68 Z9 69 U1 1 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD MAR 6 PY 2001 VL 40 IS 9 BP 2826 EP 2834 DI 10.1021/bi002417n PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 407FL UT WOS:000167261500019 PM 11258893 ER PT J AU Salaniwal, S Cui, ST Cochran, HD Cummings, PT AF Salaniwal, S Cui, ST Cochran, HD Cummings, PT TI Molecular simulation of a dichain surfactant water carbon dioxide system. 1. Structural properties of aggregates SO LANGMUIR LA English DT Article ID SODIUM OCTANOATE MICELLE; DYNAMICS SIMULATIONS; COMPUTER-SIMULATIONS; INTERMOLECULAR POTENTIALS; PHASE-EQUILIBRIA; REVERSE MICELLES; AQUEOUS-SOLUTION; MODEL MICELLES; OIL INTERFACE; GEL FORMATION AB Molecular dynamics simulation of a dichain surfactant + water + carbon dioxide (solvent) system is performed to study the structural properties of reversed micelle-like surfactant aggregates formed in the system. The simulations use a detailed and realistic molecular model for the surfactant molecule and explicit representation of the water and solvent molecules to enable quantitative comparisons with a prior experimental (small-angle neutron scattering) study. The results of the simulation are found to be in reasonable agreement with experimental values. The simulations show that the size and shape of the surfactant aggregates depends on their water-to-surfactant ratio. A higher water-to-surfactant ratio results in larger and more spherical aggregates. The two distinct tails of the surfactant molecule exhibit different conformations in carbon dioxide indicating contrasting CO2-philic behavior. The perfluoroalkane tails assume more extended conformation than the alkane tails. The microstructure of the aqueous core reveals that the water molecules in the interfacial region are strongly oriented in response to the electric fields of the anionic headgroups and sodium counterions, while water near the center of the core approaches bulklike properties with the presence of a hydrogen-bonded network. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Cummings, PT (reprint author), Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 46 TC 79 Z9 82 U1 2 U2 17 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR 6 PY 2001 VL 17 IS 5 BP 1773 EP 1783 DI 10.1021/la000554f PG 11 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 407VE UT WOS:000167290800070 ER PT J AU Salaniwal, S Cui, ST Cochran, HD Cummings, PT AF Salaniwal, S Cui, ST Cochran, HD Cummings, PT TI Molecular simulation of a dichain surfactant water carbon dioxide system. 2. Self-assembly and aggregation dynamics SO LANGMUIR LA English DT Article ID CLUSTER-CLUSTER AGGREGATION; AQUEOUS-SOLUTION; MICELLES AB We report on the aggregation dynamics of the dichain surfactant [(C7F15)(C7H15)CHSO4-Na+] + water + carbon dioxide (solvent) system described in our preceding paper. Our results indicate that the aggregation process follows a two-step mechanism: hydration of anionic headgroups and Na+ counterions followed by aggregation of hydrated surfactant molecules. The kinetics of aggregation is consistent with the Smolouchowski theory of diffusion-limited aggregation, though on a much faster time scale compared to aggregation observed in aqueous surfactant systems. This is attributed to the fact that the intermolecular interactions responsible for aggregation in the system under investigation are electrostatic in nature and the carbon dioxide permits faster diffusion of surfactant molecules than water. The surfactant tails forming the corona of the aggregates provide steric stabilization of the aggregates thereby reducing the rate of aggregation. C1 Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Cummings, PT (reprint author), Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 16 TC 35 Z9 35 U1 1 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR 6 PY 2001 VL 17 IS 5 BP 1784 EP 1792 DI 10.1021/la0005558 PG 9 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 407VE UT WOS:000167290800071 ER PT J AU Wei, YY Eres, G Merkulov, VI Lowndes, DH AF Wei, YY Eres, G Merkulov, VI Lowndes, DH TI Effect of catalyst film thickness on carbon nanotube growth by selective area chemical vapor deposition SO APPLIED PHYSICS LETTERS LA English DT Article ID CIRCUITS AB The correlation between prepatterned catalyst film thickness and carbon nanotube (CNT) growth by selective area chemical vapor deposition (CVD) was studied using Fe and Ni as catalyst. To eliminate sample-to-sample variations and create a growth environment in which the film thickness is the sole variable, samples with continuously changing catalyst film thickness from 0 to 60 nm were fabricated by electron-gun evaporation. Using thermal CVD CNTs preferentially grow as a dense mat on the thin regions of the catalyst film. Moreover, beyond a certain critical film thickness no tubes were observed. The critical film thickness for CNT growth was found to increase with substrate temperature. There appears to be no strong correlation between the film thickness and the diameter of the tubes. In contrast, using plasma enhanced CVD with Ni as catalyst, vertically oriented CNTs grow in the entire range of catalyst film thickness. The diameter of these CNTs shows a strong correlation with the catalyst film thickness. The significance of these experimental trends is discussed within the framework of the diffusion model for CNT growth. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Wei, YY (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Eres, Gyula/C-4656-2017 OI Eres, Gyula/0000-0003-2690-5214 NR 15 TC 214 Z9 217 U1 4 U2 73 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 5 PY 2001 VL 78 IS 10 BP 1394 EP 1396 DI 10.1063/1.1354658 PG 3 WC Physics, Applied SC Physics GA 405GL UT WOS:000167151300026 ER PT J AU Moussa, SM Kennedy, BJ Hunter, BA Howard, CJ Vogt, T AF Moussa, SM Kennedy, BJ Hunter, BA Howard, CJ Vogt, T TI Low temperature structural studies on PrAlO3 SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter ID NEUTRON AB The structures of PrAlO3 have been studied from room temperature to 10 K, using a combination of high resolution neutron and synchrotron powder diffraction data. At room temperature, PrAlO3 has a rhombohedral structure in space group R (3) over barc which transforms to an orthorhombic structure in Imma on lowering the temperature to about 205 K, and to a monoclinic, C2/m, structure at about 150 K. The structure becomes more nearly tetragonal as the sample is further cooled, but the high resolution diffraction confirms that the symmetry remains monoclinic in space group C2/m down to the lowest measured temperature. C1 Univ Sydney, Sch Chem, Heavy Met Res Ctr, Sydney, NSW 2006, Australia. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Univ Sydney, Australian Key Ctr Microscopy & Microanal, Sydney, NSW 2006, Australia. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Moussa, SM (reprint author), Univ Sydney, Sch Chem, Heavy Met Res Ctr, Sydney, NSW 2006, Australia. RI Howard, Christopher/B-5138-2009; Vogt, Thomas /A-1562-2011; OI Vogt, Thomas /0000-0002-4731-2787; Kennedy, Brendan/0000-0002-7187-4579 NR 16 TC 44 Z9 44 U1 1 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD MAR 5 PY 2001 VL 13 IS 9 BP L203 EP L209 DI 10.1088/0953-8984/13/9/102 PG 7 WC Physics, Condensed Matter SC Physics GA 411VG UT WOS:000167519500002 ER PT J AU Mezzacappa, A Liebendorfer, M Messer, OEB Hix, WR Thielemann, FK Bruenn, SW AF Mezzacappa, A Liebendorfer, M Messer, OEB Hix, WR Thielemann, FK Bruenn, SW TI Simulation of the spherically symmetric stellar core collapse, bounce, and postbounce evolution of a star of 13 solar masses with Boltzmann neutrino transport, and its implications for the supernova mechanism SO PHYSICAL REVIEW LETTERS LA English DT Article ID PRESUPERNOVA EVOLUTION; NUMERICAL-METHOD; MASSIVE STARS; II SUPERNOVAE; DENSE MATTER; EXPLOSIONS; CONVECTION; EQUATION; SHOCK; PHASE AB With exact three-flavor Boltzmann neutrino transport, we simulate the stellar core collapse, bounce, and postbounce evolution of a M-13(.) star in spherical symmetry, the Newtonian limit, without invoking convection. In the absence of convection, prior spherically symmetric models, which implemented approximations to Boltzmann transport, failed to produce explosions. We consider exact transport to determine if these failures were due to the transport approximations made and to answer remaining fundamental questions in supernova theory, The model presented here is the first in a sequence of models beginning with different progenitors. In this model, a supernova explosion is not obtained. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Univ Basel, Dept Phys & Astron, CH-4056 Basel, Switzerland. Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. Florida Atlantic Univ, Dept Phys, Boca Raton, FL 33431 USA. RP Mezzacappa, A (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RI Hix, William/E-7896-2011; Messer, Bronson/G-1848-2012; Mezzacappa, Anthony/B-3163-2017 OI Hix, William/0000-0002-9481-9126; Messer, Bronson/0000-0002-5358-5415; Mezzacappa, Anthony/0000-0001-9816-9741 NR 39 TC 190 Z9 191 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 5 PY 2001 VL 86 IS 10 BP 1935 EP 1938 DI 10.1103/PhysRevLett.86.1935 PG 4 WC Physics, Multidisciplinary SC Physics GA 407EU UT WOS:000167259900007 PM 11289824 ER PT J AU Abbott, B Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Balm, PW Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Bassler, U Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Dahl, OI Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Fisk, HE Fisyak, Y Flattum, E Fleuret, E Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Grinstein, S Groer, L Grudberg, P Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hou, S Huang, Y Ito, AS Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, VE Landsberg, G Leflat, A Lehner, F Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Maciel, AKA Madaras, RJ Manankov, V Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Peters, O Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Rha, J Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sculli, J Sen, N Shabalina, E Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zheng, H Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A AF Abbott, B Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Balm, PW Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Bassler, U Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Dahl, OI Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Fisk, HE Fisyak, Y Flattum, E Fleuret, E Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Grinstein, S Groer, L Grudberg, P Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hou, S Huang, Y Ito, AS Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, VE Landsberg, G Leflat, A Lehner, F Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Maciel, AKA Madaras, RJ Manankov, V Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Peters, O Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Rha, J Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sculli, J Sen, N Shabalina, E Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zheng, H Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A CA D0 Collaboration TI Ratios of multijet cross sections in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID JET AB We report on a study of the ratio of inclusive three-jet to inclusive two-jet production cross sections as a function of total transverse energy in p (p) over bar collisions at it center-of-mass energy roots = 1.8 TeV, using data collected with the DO detector during the 1992-1993 run of the Fermilab Tevatron Collider. The measurements are used to deduce preferred renormalization scales in perturbative O(alpha (3)(s)) QCD calculations in modeling soft-jet emission. C1 NYU, New York, NY 10003 USA. Columbia Univ, New York, NY 10027 USA. Univ Nebraska, Lincoln, NE 68588 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Northeastern Univ, Boston, MA 02115 USA. Boston Univ, Boston, MA 02215 USA. Univ Maryland, College Pk, MD 20742 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Kansas State Univ, Manhattan, KS 66506 USA. Univ Kansas, Lawrence, KS 66045 USA. Iowa State Univ, Ames, IA 50011 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Indiana Univ, Bloomington, IN 47405 USA. Northwestern Univ, Evanston, IL 60208 USA. No Illinois Univ, De Kalb, IL 60115 USA. Univ Illinois, Chicago, IL 60607 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Hawaii, Honolulu, HI 96822 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Calif State Univ Fresno, Fresno, CA 93740 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Arizona, Tucson, AZ 85721 USA. Univ Lancaster, Lancaster, England. Inst High Energy Phys, Protvino, Russia. Moscow State Univ, Moscow, Russia. Inst Theoret & Expt Phys, Moscow, Russia. Inst Phys Nucl, Krakow, Poland. Univ Nijmegen, NIKHEF, Nijmegen, Netherlands. Univ Amsterdam, NIKHEF, Amsterdam, Netherlands. FOM, Inst NIKHEF, NL-1098 SJ Amsterdam, Netherlands. CINVESTAV, Mexico City 14000, DF, Mexico. Seoul Natl Univ, Seoul, South Korea. Tata Inst Fundamental Res, Mumbai, India. Univ Delhi, Delhi 110007, India. Panjab Univ, Chandigarh 160014, India. CEA, DAPNIA, Serv Phys Particules, Saclay, France. Univ Paris 06, LPNHE, IN2P3, CNRS, Paris, France. Univ Paris 07, LPNHE, IN2P3, CNRS, Paris, France. Univ Mediterranee, CPPM, IN2P3, CNRS, Marseille, France. Univ Grenoble 1, IN2P3, CNRS, Inst Sci Nucl, Grenoble, France. Univ Grenoble 1, IN2P3, CNRS, Inst Sci Nucl, Grenoble, France. Univ San Francisco Quito, Quito, Ecuador. Acad Sci Czech Republ, Inst Phys, Prague, Czech Republic. Charles Univ, Prague, Czech Republic. Univ Los Andes, Bogota, Colombia. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Estado Rio De Janeiro, Rio De Janeiro, Brazil. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. Univ Buenos Aires, Buenos Aires, DF, Argentina. Univ Rochester, Rochester, NY 14627 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Langston Univ, Langston, OK 73050 USA. Univ Oklahoma, Norman, OK 73019 USA. Brown Univ, Providence, RI 02912 USA. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. Rice Univ, Houston, TX 77005 USA. Univ Washington, Seattle, WA 98195 USA. RP Abbott, B (reprint author), NYU, New York, NY 10003 USA. RI Canelli, Florencia/O-9693-2016; Sznajder, Andre/L-1621-2016; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Leflat, Alexander/D-7284-2012; Dudko, Lev/D-7127-2012; Merkin, Mikhail/D-6809-2012; Yip, Kin/D-6860-2013; Kuleshov, Sergey/D-9940-2013; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Belyaev, Alexander/F-6637-2015; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015 OI Canelli, Florencia/0000-0001-6361-2117; Sznajder, Andre/0000-0001-6998-1108; Dudko, Lev/0000-0002-4462-3192; Yip, Kin/0000-0002-8576-4311; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489; Belyaev, Alexander/0000-0002-1733-4408; Kim, Sun Kee/0000-0002-0013-0775; NR 8 TC 10 Z9 10 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 5 PY 2001 VL 86 IS 10 BP 1955 EP 1960 DI 10.1103/PhysRevLett.86.1955 PG 6 WC Physics, Multidisciplinary SC Physics GA 407EU UT WOS:000167259900012 PM 11289829 ER PT J AU Afanasiev, SV Anticic, T Bachler, J Barna, D Barnby, LS Bartke, J Barton, RA Betev, L Bialkowska, H Billmeier, A Blume, C Blyth, CO Boimska, B Botje, M Bracinik, J Brady, FP Bramm, R Brun, R Buncic, P Carr, L Cebra, D Cooper, GE Cramer, JG Csato, P Eckardt, V Eckhardt, F Ferenc, D Filip, P Fischer, HG Fodor, Z Foka, P Freund, P Friese, V Ftacnik, J Gal, J Gazdzicki, M Georgopoulos, G Gladysz, E Harris, JW Hegyi, S Hlinka, V Hohne, C Igo, G Ivanov, M Jacobs, P Janik, R Jones, PG Kadija, K Kolesnikov, VI Kollegger, T Kowalski, M Lasiuk, B van Leeuwen, M Levai, P Malakhov, AI Margetis, S Markert, C Mayes, BW Melkumov, GL Mischke, A Molnar, J Nelson, JM Odyniec, G Palla, G Panagiotou, AD Petridis, A Pikna, M Pinsky, L Poskanzer, AM Prindle, DJ Puhlhofer, F Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rybicki, A Sammer, T Sandoval, A Sann, H Schafer, E Schmitz, N Seyboth, P Sikler, F Sitar, B Skrzypczak, E Snellings, R Squier, GTA Stock, R Strmen, P Strobele, H Susa, T Szarka, I Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Ullrich, T Varga, D Vassiliou, M Veres, GI Vesztergombi, G Voloshin, S Vranic, D Wang, F Weerasundara, DD Wenig, S Wetzler, A Whitten, C Xu, N Yates, TA Yoo, IK Zimanyi, J AF Afanasiev, SV Anticic, T Bachler, J Barna, D Barnby, LS Bartke, J Barton, RA Betev, L Bialkowska, H Billmeier, A Blume, C Blyth, CO Boimska, B Botje, M Bracinik, J Brady, FP Bramm, R Brun, R Buncic, P Carr, L Cebra, D Cooper, GE Cramer, JG Csato, P Eckardt, V Eckhardt, F Ferenc, D Filip, P Fischer, HG Fodor, Z Foka, P Freund, P Friese, V Ftacnik, J Gal, J Gazdzicki, M Georgopoulos, G Gladysz, E Harris, JW Hegyi, S Hlinka, V Hohne, C Igo, G Ivanov, M Jacobs, P Janik, R Jones, PG Kadija, K Kolesnikov, VI Kollegger, T Kowalski, M Lasiuk, B van Leeuwen, M Levai, P Malakhov, AI Margetis, S Markert, C Mayes, BW Melkumov, GL Mischke, A Molnar, J Nelson, JM Odyniec, G Palla, G Panagiotou, AD Petridis, A Pikna, M Pinsky, L Poskanzer, AM Prindle, DJ Puhlhofer, F Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rybicki, A Sammer, T Sandoval, A Sann, H Schafer, E Schmitz, N Seyboth, P Sikler, F Sitar, B Skrzypczak, E Snellings, R Squier, GTA Stock, R Strmen, P Strobele, H Susa, T Szarka, I Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Ullrich, T Varga, D Vassiliou, M Veres, GI Vesztergombi, G Voloshin, S Vranic, D Wang, F Weerasundara, DD Wenig, S Wetzler, A Whitten, C Xu, N Yates, TA Yoo, IK Zimanyi, J CA NA49 Collaboration TI Event-by-event fluctuations of the kaon-to-pion ratio in central Pb plus Pb collisions at 158 GeV per nucleon SO PHYSICAL REVIEW LETTERS LA English DT Article AB We present the first measurement of fluctuations from event to event in the production of strange particles in collisions of heavy nuclei. The ratio of charged kaons to charged pions is determined for individual central Pb + Pb collisions. After accounting for the fluctuations due to detector resolution and finite number statistics we derive ant upper limit on genuine nonstatistical fluctuations, which could be related to a first- or second-order QCD phase transition. Such fluctuations Lire shown to be very small. C1 Joint Inst Nucl Res, Dubna 141980, Russia. Univ Calif Davis, Davis, CA 95616 USA. Gesell Schwerionenforsch GmbH, GSI, D-64220 Darmstadt, Germany. Inst Nucl Phys, PL-30055 Krakow, Poland. CERN, CH-1211 Geneva, Switzerland. MIT, Cambridge, MA 02139 USA. KFKI Res Inst Particle & Nucl Phys, H-1121 Budapest, Hungary. Comenius Univ, Bratislava 84215, Slovakia. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Athens, Dept Phys, GR-15771 Athens, Greece. Univ Frankfurt, Fachbereich Phys, D-60486 Frankfurt, Germany. Univ Houston, Houston, TX 77204 USA. Kent State Univ, Kent, OH 44242 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Marburg, Fachbereich Phys, D-35032 Marburg, Germany. Max Planck Inst Phys, D-80505 Munich, Germany. Yale Univ, New Haven, CT 06520 USA. Inst Nucl Studies, PL-00681 Warsaw, Poland. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. Univ Washington, Nucl Phys Lab, Seattle, WA 98195 USA. Rudjer Boskovic Inst, Zagreb 10000, Croatia. NIKHEF H, Amsterdam, Netherlands. RP Afanasiev, SV (reprint author), Joint Inst Nucl Res, Dubna 141980, Russia. RI Barnby, Lee/G-2135-2010; Mischke, Andre/D-3614-2011; Voloshin, Sergei/I-4122-2013; Levai, Peter/A-1544-2014; Carr, Lincoln/E-3819-2016; OI Barnby, Lee/0000-0001-7357-9904; Carr, Lincoln/0000-0002-4848-7941; van Leeuwen, Marco/0000-0002-5222-4888 NR 16 TC 77 Z9 79 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 5 PY 2001 VL 86 IS 10 BP 1965 EP 1969 DI 10.1103/PhysRevLett.86.1965 PG 5 WC Physics, Multidisciplinary SC Physics GA 407EU UT WOS:000167259900014 PM 11289831 ER PT J AU Back, BB Betts, RR Chang, J Chang, WC Chi, CY Chu, YY Cumming, JB Dunlop, JC Eldredge, W Fung, SY Ganz, R Garcia, E Gillitzer, A Heintzelman, G Henning, WF Hofman, DJ Holzman, B Kang, JH Kim, EJ Kim, SY Kwon, Y McLeod, D Mignerey, AC Moulson, M Nanal, V Ogilvie, CA Pak, R Ruangma, A Russ, DE Seto, RK Stanskas, PJ Stephans, GSF Wang, HQ Wolfs, FLH Wuosmaa, AH Xiang, H Xu, GH Yao, HB Zou, CM AF Back, BB Betts, RR Chang, J Chang, WC Chi, CY Chu, YY Cumming, JB Dunlop, JC Eldredge, W Fung, SY Ganz, R Garcia, E Gillitzer, A Heintzelman, G Henning, WF Hofman, DJ Holzman, B Kang, JH Kim, EJ Kim, SY Kwon, Y McLeod, D Mignerey, AC Moulson, M Nanal, V Ogilvie, CA Pak, R Ruangma, A Russ, DE Seto, RK Stanskas, PJ Stephans, GSF Wang, HQ Wolfs, FLH Wuosmaa, AH Xiang, H Xu, GH Yao, HB Zou, CM CA E917 Collaboration TI Baryon rapidity loss in relativistic Au plus Au collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID AU+AU COLLISIONS; 11.6A GEV/C; NUCLEUS COLLISIONS; ENERGY; PROTON AB An excitation function of proton rapidity distributions for different centralities is reported from AGS Experiment E917 for Au + Au collisions at 6, 8, and 10.8 GeV/nucleon. The rapidity distributions from peripheral collisions have a valley at midrapidity which smoothly change tr, distributions that display a broad peak at midrapidity for central collisions. The mean rapidity loss increases with increasing beam energy, whereas the fraction of protons consistent with isotropic emission from a stationary source at midrapidity decreases with increasing beam energy. The data suggest that the stopping is substantially less than complete at these energies. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Columbia Univ, Nevis Labs, Irvington, NY 10533 USA. Univ Illinois, Chicago, IL 60607 USA. Univ Maryland, College Pk, MD 20742 USA. MIT, Cambridge, MA 02139 USA. Univ Rochester, Rochester, NY 14627 USA. Yonsei Univ, Seoul 120749, South Korea. RP Back, BB (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Mignerey, Alice/D-6623-2011; seto, richard/G-8467-2011; Cumming, James/I-3358-2013; OI Cumming, James/0000-0001-6930-0958; Holzman, Burt/0000-0001-5235-6314 NR 16 TC 105 Z9 111 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 5 PY 2001 VL 86 IS 10 BP 1970 EP 1973 DI 10.1103/PhysRevLett.86.1970 PG 4 WC Physics, Multidisciplinary SC Physics GA 407EU UT WOS:000167259900015 PM 11289832 ER PT J AU Prabhakar, S Fox, JD Teytelman, D AF Prabhakar, S Fox, JD Teytelman, D TI Curing coupled-bunch instabilities with uneven fills SO PHYSICAL REVIEW LETTERS LA English DT Article AB A new, unified theoretical description of coupled-bunch instabilities in unevenly filled storage rings is presented. Uneven-fill longitudinal dynamics are explained in terms of two physical phenomena: fill-induced tune-spread damping and modulation coupling of strong even-fill eigenmodes. The latter is also present in the transverse plane. The analysis yields simple criteria for optimizing fill shapes to reduce the growth rates of the most unstable modes. Experimental results from the ALS and PEP-II are shown to be in good agreement with the theory. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Prabhakar, S (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 27 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 5 PY 2001 VL 86 IS 10 BP 2022 EP 2025 DI 10.1103/PhysRevLett.86.2022 PG 4 WC Physics, Multidisciplinary SC Physics GA 407EU UT WOS:000167259900028 PM 11289845 ER PT J AU Webb, EB Grest, GS AF Webb, EB Grest, GS TI Liquid/vapor surface tension of metals: Embedded atom method with charge gradient corrections SO PHYSICAL REVIEW LETTERS LA English DT Article ID FCC METALS; MOLECULAR-DYNAMICS; ALLOYS; NI; AL; CU; AG; AU; PD AB Molecular dynamics simulations for three embedded atom method (EAM) function sets are used to determine the liquid/vapor surface tension gamma for Al, Ni, Cu, Ag, and Au. The three EAM models differ in both the functional forms employed and the fitting procedure used. All the EAM potentials underestimate gamma but one of the models performs consistently better than the others. We show that including a correction to the local charge density associated with gradients in the density together with exploiting the invariance of the EAM potentials to appropriate transformations in the charge density can lead to improved values for gamma, as well as for solid free surface energies, within existing EAM function sets. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Webb, EB (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 35 Z9 35 U1 1 U2 12 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 5 PY 2001 VL 86 IS 10 BP 2066 EP 2069 DI 10.1103/PhysRevLett.86.2066 PG 4 WC Physics, Multidisciplinary SC Physics GA 407EU UT WOS:000167259900039 PM 11289856 ER PT J AU Rignanese, GM Blase, X Louie, SG AF Rignanese, GM Blase, X Louie, SG TI Quasiparticle effects on tunneling currents: A study of C2H4 adsorbed on the Si(001)-(2 x 1) surface SO PHYSICAL REVIEW LETTERS LA English DT Article ID SI(100)-(2X1) SURFACE; ELECTRONIC-STRUCTURE; BAND-GAPS; ETHYLENE; ADSORPTION; SEMICONDUCTORS; 1ST-PRINCIPLES; INSULATORS; ENERGIES; CONTRAST AB We present a first-principles calculation of the quasiparticlc: electronic structure of ethylene adsorbed on the dimer reconstructed Si(001)-(2 X 1) surface. Within the GW approximation, the self-energy corrections for the adsorbate states are found to be about 1.5 eV larger than those for the states derived from bulk silicon. The calculated quasiparticle band structure is in excellent agreement with photoemission spectra. Finally, the effects of the quasiparticle corrections on the scanning tunneling microscope images of the adsorbed molecules are shown to be important as the lowering of the C2H4 energy levels within GW strongly reduces their tunneling probability. C1 Catholic Univ Louvain, Unite Physicochim & Phys Mat, B-1348 Louvain, Belgium. Dept Phys Mat, F-69622 Villeurbanne, France. CNRS, UMR 5586, F-69622 Villeurbanne, France. Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Catholic Univ Louvain, Unite Physicochim & Phys Mat, 1 Pl Croix Sud, B-1348 Louvain, Belgium. RI Rignanese, Gian-Marco/A-7435-2008 OI Rignanese, Gian-Marco/0000-0002-1422-1205 NR 29 TC 28 Z9 28 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 5 PY 2001 VL 86 IS 10 BP 2110 EP 2113 DI 10.1103/PhysRevLett.86.2110 PG 4 WC Physics, Multidisciplinary SC Physics GA 407EU UT WOS:000167259900050 PM 11289867 ER PT J AU Havel, TF Sharf, Y Viola, L Cory, DG AF Havel, TF Sharf, Y Viola, L Cory, DG TI Hadamard products of product operators and the design of gradient-diffusion experiments for simulating decoherence by NMR spectroscopy SO PHYSICS LETTERS A LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; QUANTUM ERROR-CORRECTION; GEOMETRIC ALGEBRA; PULSE EXPERIMENTS; LOGIC GATES; FORMALISM AB An extension of the product operator formalism of NMR is introduced, which uses the Hadamard matrix product to describe many simple spin 1/2 relaxation processes. The utility of this formalism is illustrated by deriving NMR gradient-diffusion experiments to simulate several decoherence models of interest in quantum information processing, along with their Lindblad and Kraus representations. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Harvard Univ, Sch Med, BCMP, Boston, MA 02115 USA. MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Havel, TF (reprint author), Harvard Univ, Sch Med, BCMP, 240 Longwood Ave, Boston, MA 02115 USA. NR 33 TC 27 Z9 27 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD MAR 5 PY 2001 VL 280 IS 5-6 BP 282 EP 288 DI 10.1016/S0375-9601(01)00083-4 PG 7 WC Physics, Multidisciplinary SC Physics GA 411CE UT WOS:000167479900009 ER PT J AU Kriesel, JW Sander, MS Tilley, TD AF Kriesel, JW Sander, MS Tilley, TD TI General route to homogeneous, mesoporous, multicomponent oxides based on the thermolytic transformation of molecular precursors in non-polar media SO ADVANCED MATERIALS LA English DT Article ID SOL-GEL METHOD; ZIRCONIUM-OXIDE; SIEVES; SILICA; COMPLEXES; SURFACTANTS; CATALYSTS; PHOSPHATE 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 32 TC 50 Z9 51 U1 0 U2 10 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0935-9648 J9 ADV MATER JI Adv. Mater. PD MAR 2 PY 2001 VL 13 IS 5 BP 331 EP 335 DI 10.1002/1521-4095(200103)13:5<331::AID-ADMA331>3.0.CO;2-0 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 415AU UT WOS:000167699000008 ER PT J AU Gerasimov, MR Schiffer, WK Gardner, EL Marsteller, DA Lennon, IC Taylor, SJC Brodie, JD Ashby, CR Dewey, SL AF Gerasimov, MR Schiffer, WK Gardner, EL Marsteller, DA Lennon, IC Taylor, SJC Brodie, JD Ashby, CR Dewey, SL TI GABAergic blockade of cocaine-associated cue-induced increases in nucleus accumbens dopamine SO EUROPEAN JOURNAL OF PHARMACOLOGY LA English DT Article DE cocaine; conditioning; contextual cue; microdialysis; in vivo; GABA (gamma-aminobutyric acid); vigabatrin ID CONDITIONED PLACE PREFERENCE; SELF-ADMINISTERED COCAINE; EXTRACELLULAR DOPAMINE; SEEKING BEHAVIOR; ANIMAL-MODEL; REWARD; HEROIN; RATS; REINSTATEMENT; AMYGDALA AB Environments previously associated with drug use can become one of the most common factors triggering relapse to drug-seeking behavior. To better understand the neurochemical mechanisms potentially mediating these cues, we measured nucleus accumbens dopamine levels in animals exposed to environmental cues previously paired with cocaine administration. In animals exposed to a cocaine-paired environment nucleus accumbens dopamine increased by 25%. When administered 2.5 h prior to presentation of the environmental trigger, racemic vigabatrin tan irreversible inhibitor of gamma -aminobutyric acid (GABA)-transaminase) abolished this cue-induced increase. Conversely, R-(-)-vigabatrin, the inactive enantiomer, had no effect. Combined with our earlier findings, these studies support the potential therapeutic benefit of this enzyme-based GABAergic strategy to modulate brain dopamine and the subsequent treatment of drug addiction. (C) 2001 Elsevier Science B.V. All rights: reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NIDA, Intramural Res Program, Baltimore, MD 21224 USA. Chirotech Technol Ltd, Cambridge CB4 0WG, England. NYU, Sch Med, Dept Psychiat, New York, NY 10016 USA. St Johns Univ, Dept Pharmaceut Hlth Sci, Jamaica, NY 11439 USA. RP Gerasimov, MR (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NIMH NIH HHS [MH49165]; PHS HHS [R2955155] NR 24 TC 44 Z9 46 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0014-2999 J9 EUR J PHARMACOL JI Eur. J. Pharmacol. PD MAR 2 PY 2001 VL 414 IS 2-3 BP 205 EP 209 DI 10.1016/S0014-2999(01)00800-7 PG 5 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 411EM UT WOS:000167485200010 PM 11239920 ER PT J AU Lake, B Aeppli, G Clausen, KN McMorrow, DF Lefmann, K Hussey, NE Mangkorntong, N Nohara, M Takagi, H Mason, TE Schroder, A AF Lake, B Aeppli, G Clausen, KN McMorrow, DF Lefmann, K Hussey, NE Mangkorntong, N Nohara, M Takagi, H Mason, TE Schroder, A TI Spins in the vortices of a high-temperature superconductor SO SCIENCE LA English DT Article ID DENSITY-OF-STATES; MAGNETIC FLUCTUATIONS; VORTEX; LINES; GAP; LA2-XSRXCUO4; SCATTERING; TRANSITION; LATTICE; FIELDS AB Neutron scattering is used to characterize the magnetism of the vortices for the optimally doped high-temperature superconductor La2-xSrxCuO4 (x = 0.163) in an applied magnetic field. As temperature is reduced, Low-frequency spin fluctuations first disappear with the loss of vortex mobility, but then reappear. We find that the vortex state can be regarded as an inhomogeneous mixture of a superconducting spin fluid and a material containing a nearly ordered antiferromagnet. These experiments show that as for many other properties of cuprate superconductors, the important underlying microscopic forces are magnetic. C1 NEC Res, Princeton, NJ 08540 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Riso Natl Lab, Dept Condensed Matter Phys & Chem, DK-4000 Roskilde, Denmark. Univ Tokyo, Grad Sch Frontier Sci, Dept Adv Mat Sci, Bunkyo Ku, Tokyo 1138656, Japan. Univ Loughborough, Dept Phys, Loughborough LE11 3TU, Leics, England. Univ Karlsruhe, Inst Phys, D-76128 Karlsruhe, Germany. RP Aeppli, G (reprint author), NEC Res, 4 Independence Way, Princeton, NJ 08540 USA. RI McMorrow, Desmond/C-2655-2008; Takagi, Hidenori/B-2935-2010; NOHARA, Minoru/B-1476-2011; Mason, Thomas/M-5809-2014; Lefmann, Kim/M-9228-2014; Hussey, Nigel/F-9699-2015; OI McMorrow, Desmond/0000-0002-4947-7788; Mason, Thomas/0000-0003-1880-3971; Lefmann, Kim/0000-0003-4282-756X; Lake, Bella/0000-0003-0034-0964 NR 29 TC 278 Z9 281 U1 2 U2 25 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAR 2 PY 2001 VL 291 IS 5509 BP 1759 EP 1762 DI 10.1126/science.1056986 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 408HK UT WOS:000167320600051 PM 11230686 ER PT J AU Neu, MP Johnson, MT Matonic, JH Scott, BL AF Neu, MP Johnson, MT Matonic, JH Scott, BL TI Actinide interactions with microbial chelators: the dioxobis[pyridine-2,6-bis(monothiocarboxylato)]uranium(VI) ion SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID CRYSTAL-STRUCTURE; PYRIDINE-2,6-BIS(THIOCARBOXYLATE); HEXAHYDRATE; ACID AB The title complex, bis(tetraphenylphosphonium) dioxobis(pyridine-2,6-dicarbothioato-O,N,O')uranium(VI), (C24H20P)(2)-[UO2(C7H3NO2S2)(2)], was prepared by reacting two equivalents of pyridine-2,6-bis(monothiocarboxylate) (pdtc) with uranyl nitrate. The geometry of the eight-coordinate U atom is hexagonal bipyramidal, with the uranyl O atoms in apical positions. This is the first reported complex in which this ligand binds a metal through the O and not the S atoms. Principal bond lengths include uranyl lengths of 1.774 (2) Angstrom, U-O distances of 2.434 (2) and 2.447 (3) Angstrom, and two U-N distances of 2.647 (3) Angstrom. The anion lies on an inversion centre. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Neu, MP (reprint author), Univ Calif Los Alamos Natl Lab, MS G739, Los Alamos, NM 87545 USA. RI Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 12 TC 12 Z9 12 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD MAR PY 2001 VL 57 BP 240 EP 242 DI 10.1107/S0108270100017285 PN 3 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 411FU UT WOS:000167488100007 PM 11250561 ER PT J AU Ciszak, E Korotchkina, LG Hong, YS Joachimiak, A Patel, MS AF Ciszak, E Korotchkina, LG Hong, YS Joachimiak, A Patel, MS TI Crystallization and initial X-ray diffraction analysis of human pyruvate dehydrogenase SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID MULTIENZYME COMPLEX; PYROPHOSPHATE; BINDING AB Human pyruvate dehydrogenase (E1) is a component enzyme of the pyruvate dehydrogenase complex. The enzyme catalyzes the irreversible decarboxylation of pyruvic acid and the rate-limiting reductive acetylation of the lipoyl moiety linked to the dihydrolipoamide acetyltransferase component of the pyruvate dehydrogenase complex. E1 is an alpha (2)beta (2) tetramer (similar to 154 kDa). Crystals of this recombinant enzyme have been grown in polyethylene glycol 3350 using a vapor-diffusion method at 295 K. The crystals are characterized as orthorhombic, space group P2(1)2(1)2(1), with unit-cell parameters a = 64.2, b = 126.9, c = 190.2 Angstrom. Crystals diffracted to a minimum d spacing of 2.5 Angstrom. The asymmetric unit contains one alpha (2)beta (2) tetrameric E1 assembly; self-rotation function analysis showed a pseudo-twofold symmetry relating the two alpha beta dimers. C1 Univ Space Res Assoc, Huntsville, AL 35803 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. SUNY Buffalo, Dept Biochem, Sch Med & Biomed Sci, Buffalo, NY 14214 USA. Argonne Natl Lab, Struct Biol Ctr, Argonne, IL 60439 USA. RP Ciszak, E (reprint author), Univ Space Res Assoc, 4950 Corp Dr, Huntsville, AL 35803 USA. FU NIDDK NIH HHS [DK20478] NR 20 TC 2 Z9 5 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD MAR PY 2001 VL 57 BP 465 EP 468 DI 10.1107/S0907444901000427 PN 3 PG 4 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 406TP UT WOS:000167231500024 PM 11223534 ER PT J AU Butler, PA Chewter, AJ Kankaanpaa, H Herzberg, RD Becker, F Cocks, JFC Dorvaux, O Eskola, K Gerl, J Greenlees, PT Hammond, N Helariutta, K Hessberger, FP Houry, M Humphreys, RD Hurstel, A Jones, GD Jones, PM Julin, R Juutinen, S Keenan, A Kettunen, H Khoo, TL Korten, W Kuusiniemi, P Le Coz, Y Leino, M Lucas, R Muikku, M Nieminen, P Page, RD Page, T Rahkila, P Reiter, P Savelius, A Schlegel, C Theisen, C Trzaska, WH Uusitalo, J Wollersheim, HJ AF Butler, PA Chewter, AJ Kankaanpaa, H Herzberg, RD Becker, F Cocks, JFC Dorvaux, O Eskola, K Gerl, J Greenlees, PT Hammond, N Helariutta, K Hessberger, FP Houry, M Humphreys, RD Hurstel, A Jones, GD Jones, PM Julin, R Juutinen, S Keenan, A Kettunen, H Khoo, TL Korten, W Kuusiniemi, P Le Coz, Y Leino, M Lucas, R Muikku, M Nieminen, P Page, RD Page, T Rahkila, P Reiter, P Savelius, A Schlegel, C Theisen, C Trzaska, WH Uusitalo, J Wollersheim, HJ TI Towards in-beam spectroscopy of the heaviest elements SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT XXXVth Zakopane School of Physics on Trends in Nuclear Physics CY SEP 05-13, 2000 CL ZAKOPANE, POLAND SP Polish State Comm Sci Res, PerkinElmer Instruments, Minist Natl Educ ID SUPERHEAVY NUCLEI; NO-254 AB New developments in nuclear spectroscopy of prompt emission at the target and decay emission at the focal plane of recoil separators are described here. In-beam gamma -ray measurements of even-even nuclei in the rotational superheavy region, No-252,No-254, have been carried out. These measurements have revealed the properties of the ground state rotational bands. Attempts to measure the properties of odd mass nuclei await the further development of conversion electron spectroscopy, and early results from the SACRED spectrometer used in conjunction with the recoil separator RITU are given here. The future development of sensitive focal plane instruments, to identify decay processes following the radioactive decay of the parent nucleus is also described. C1 Univ Liverpool, Oliver Lodge Lab, Liverpool L69 3BX, Merseyside, England. Univ Jyvaskyla, Dept Phys, Jyvaskyla, Finland. CEA Saclay, DAPNIA, SPhN, F-91191 Gif Sur Yvette, France. GSI Darmstadt, D-6100 Darmstadt, Germany. Univ Munich, Munich, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. RP Butler, PA (reprint author), Univ Liverpool, Oliver Lodge Lab, Liverpool L69 3BX, Merseyside, England. RI Herzberg, Rolf-Dietmar/E-1558-2011; Houry, Michael/G-8021-2011; KORTEN, Wolfram/H-3043-2013; THEISEN, Christophe/A-9343-2015; OI THEISEN, Christophe/0000-0002-8509-1022; KORTEN, Wolfram/0000-0002-3940-0816; Hammond, Neil/0000-0001-6390-8874; Butler, Peter/0000-0001-6080-9205 NR 17 TC 3 Z9 3 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD MAR PY 2001 VL 32 IS 3 BP 619 EP 627 PG 9 WC Physics, Multidisciplinary SC Physics GA 422LN UT WOS:000168119900002 ER PT J AU Napiorkowski, PJ Srebrny, J Czosnyka, T Gerl, J Schlegel, C Wollersheim, HJ Cline, D Wu, CY Teng, R Vetter, K Macchiavelli, A Devlin, M DeBoer, J Iwanicki, J Kownacki, J Loewe, M Wuerkner, M AF Napiorkowski, PJ Srebrny, J Czosnyka, T Gerl, J Schlegel, C Wollersheim, HJ Cline, D Wu, CY Teng, R Vetter, K Macchiavelli, A Devlin, M DeBoer, J Iwanicki, J Kownacki, J Loewe, M Wuerkner, M TI Coulomb excitation of the K-pi=8(-) isomeric band in Hf-178 SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT XXXVth Zakopane School of Physics on Trends in Nuclear Physics CY SEP 05-13, 2000 CL ZAKOPANE, POLAND SP Polish State Comm Sci Res, PerkinElmer Instruments, Minist Natl Educ ID DEPOPULATION AB The Coulomb excitation experiment on the Hf-178 was performed using 650 MeV beam of Xe-136. The first observation of discrete transitions in the K-pi = 8(-) isomeric band, Coulomb excited from K-pi = 0(+) ground state, is reported. The possible mechanisms of E1 coupling of the ground state band and the isomeric band is discussed. C1 Warsaw Univ, Heavy Ion Lab, Warsaw, Poland. Warsaw Univ, Inst Expt Phys, Warsaw, Poland. GSI Darmstadt, D-6100 Darmstadt, Germany. Univ Rochester, Rochester, NY 14627 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. St Louis Univ, St Louis, MO 63103 USA. Univ Munich, D-80539 Munich, Germany. RP Napiorkowski, PJ (reprint author), Warsaw Univ, Heavy Ion Lab, Warsaw, Poland. RI Devlin, Matthew/B-5089-2013 OI Devlin, Matthew/0000-0002-6948-2154 NR 8 TC 1 Z9 1 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD MAR PY 2001 VL 32 IS 3 BP 861 EP 864 PG 4 WC Physics, Multidisciplinary SC Physics GA 422LN UT WOS:000168119900033 ER PT J AU Hamilton, JH Luo, YX Hwang, JK Jones, EF Ramayya, AV Zhu, SH Gore, PM Beyer, CJ Kormicki, J Zhang, XQ Ginter, TN Wang, MG Cole, JD Drigert, MW Ma, WC Varmette, PG Ter-Akopian, GM Oganessian, YT Daniel, AV Kliman, J Rasmussen, JO Lee, IY Donangelo, R de Lima, AP AF Hamilton, JH Luo, YX Hwang, JK Jones, EF Ramayya, AV Zhu, SH Gore, PM Beyer, CJ Kormicki, J Zhang, XQ Ginter, TN Wang, MG Cole, JD Drigert, MW Ma, WC Varmette, PG Ter-Akopian, GM Oganessian, YT Daniel, AV Kliman, J Rasmussen, JO Lee, IY Donangelo, R de Lima, AP TI Octupole correlations and deformation in Ba, La and Pr SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT XXXVth Zakopane School of Physics on Trends in Nuclear Physics CY SEP 05-13, 2000 CL ZAKOPANE, POLAND SP Polish State Comm Sci Res, PerkinElmer Instruments, Minist Natl Educ ID NEUTRON-RICH; SPONTANEOUS FISSION; SUPERDEFORMED BAND; BARIUM ISOTOPES; NUCLEI; BA-145; MASS; SHAPES; MODES AB Stable octupole deformation was predicted and subsequently found to occur centered around the reinforcing shell gaps at Z = 56 and N = 88 for beta (3) similar or equal to 0.15 Evidence for stable octupole deformation is reviewed. New results in Ba-145 and Ba-141 are presented. Rotational enhancement of octupole deformation is found at intermittent spills ill Ba and La nuclei and the quenching of such deformation at higher spins in Ba-146 but not in Ba-144. Symmetric and asymmetric shapes coexist in Ba-145 and La-145. Evidence for octupole correlation is found in Pr-147 but only h(11/2) bands are found in Pr-149,Pr-151. The new Ba-141 levels have two sets of two intertwined bands of levels with the characteristics of octupole deformation as found in Ba-143,Ba-145, however, a problem occurs with the assignment of parities in Ba-141. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Univ Coimbra, Dept Phys, P-3000 Coimbra, Portugal. Univ Fed Rio de Janeiro, Inst Fis, Rio De Janeiro, Brazil. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Slovak Acad Sci, Inst Phys, Bratislava, Slovakia. Joint Inst Nucl Res, Dubna 141980, Russia. Mississippi State Univ, Dept Phys, Mississippi State, MS 39762 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Tsing Hua Univ, Dept Phys, Beijing 100084, Peoples R China. Joint Inst Heavy Ion Res, Oak Ridge, TN 37835 USA. Inst Modern Phys, Lanzhou 730000, Peoples R China. RP Hamilton, JH (reprint author), Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. OI Hwang, Jae-Kwang/0000-0002-4100-3473 NR 26 TC 8 Z9 8 U1 0 U2 1 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD MAR PY 2001 VL 32 IS 3 BP 957 EP 969 PG 13 WC Physics, Multidisciplinary SC Physics GA 422LN UT WOS:000168119900044 ER PT J AU Rykaczewski, KP Batchelder, JC Bingham, CR Ginter, TN Gross, CJ Grzywacz, RK Hamilton, JH Hartley, DJ Janas, Z Karny, M Kulp, WD Lipoglavsek, M McConnell, JW Momayezi, M Piechaczek, A Tantawy, MN Wahl, J Walters, WB Winger, JA Zganjar, EF AF Rykaczewski, KP Batchelder, JC Bingham, CR Ginter, TN Gross, CJ Grzywacz, RK Hamilton, JH Hartley, DJ Janas, Z Karny, M Kulp, WD Lipoglavsek, M McConnell, JW Momayezi, M Piechaczek, A Tantawy, MN Wahl, J Walters, WB Winger, JA Zganjar, EF TI Fine studies of proton radioactivity with digital signal processing SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT XXXVth Zakopane School of Physics on Trends in Nuclear Physics CY SEP 05-13, 2000 CL ZAKOPANE, POLAND SP Polish State Comm Sci Res, PerkinElmer Instruments, Minist Natl Educ ID DRIP-LINE; NPNN SCHEME; NUCLEI; EMITTERS; IDENTIFICATION; DECAY AB Recent proton radioactivity studies at tile Holifield Radioactive Ion Beam Facility at Oak Ridge are presented. The experiments were performed by means of a Recoil Mass Separator (RMS) and digital processing of its detector signals. Observation of fine structure in proton emission from the activities : Tm-145 (T-1/2 approximate to 3 mus) and Tm-146m,Tm-gs (T-1/2 approximate to 200 ms and 100 ms, respectively) is reported. The structure of the proton emitting states is analyzed in terms of a spherical approach. The properties of daughter states, a 2(+) state in Er-144 and the s(1/2) and h(11/2) neutron levels in Er-145, are deduced. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Mississippi State Univ, Dept Phys, Mississippi State, MS 39762 USA. Univ Maryland, Dept Chem, College Pk, MD 20742 USA. Louisiana State Univ, Dept Phys, Baton Rouge, LA 70803 USA. Xray Instrumentat Associates, Newark, CA 94560 USA. Georgia Inst Technol, Dept Phys, Atlanta, GA 30332 USA. Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37831 USA. Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Oak Ridge Associated Univ, UNIRIB, Oak Ridge, TN 37831 USA. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. RP Rykaczewski, KP (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 38 TC 5 Z9 5 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD MAR PY 2001 VL 32 IS 3 BP 971 EP 983 PG 13 WC Physics, Multidisciplinary SC Physics GA 422LN UT WOS:000168119900045 ER PT J AU Palacz, M Fahlander, C Sohler, D Rudolph, D Blomqvist, J Kownacki, J Lagergren, K Norlin, LO Nyberg, J Algora, A Andreoiu, C de Angelis, G Atac, A Bazzacco, D Berglund, L Back, T Cederkall, J Cederwall, B Dombradi, Z Fant, B Farnea, E Gadea, A Gorska, M Grawe, H Hashimoto-Saitoh, N Johnson, A Kerek, A Klamra, W Lenzi, SM Likar, A Lipoglavsek, M Moszynski, M Napoli, D Rossi-Alvarez, C Roth, H Saitoh, T Seweryniak, D Skeppstedt, J Weiszflog, M Wolinska, M AF Palacz, M Fahlander, C Sohler, D Rudolph, D Blomqvist, J Kownacki, J Lagergren, K Norlin, LO Nyberg, J Algora, A Andreoiu, C de Angelis, G Atac, A Bazzacco, D Berglund, L Back, T Cederkall, J Cederwall, B Dombradi, Z Fant, B Farnea, E Gadea, A Gorska, M Grawe, H Hashimoto-Saitoh, N Johnson, A Kerek, A Klamra, W Lenzi, SM Likar, A Lipoglavsek, M Moszynski, M Napoli, D Rossi-Alvarez, C Roth, H Saitoh, T Seweryniak, D Skeppstedt, J Weiszflog, M Wolinska, M TI Investigations of neutron deficient nuclei close to Sn-100 with EUROBALL SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT XXXVth Zakopane School of Physics on Trends in Nuclear Physics CY SEP 05-13, 2000 CL ZAKOPANE, POLAND SP Polish State Comm Sci Res, PerkinElmer Instruments, Minist Natl Educ ID DETECTORS; TESTS AB Excited states of nuclei in the vicinity of Sn-100 have been studied using: the EUROBALL detector array. Gamma-ray lines from Sn-103 have been identified for the first time, and a level scheme of low-lying excited states of Sn-103 has been established. New constraints on energies of single particle orbitals with respect to the Sn-100 core are obtained. C1 Univ Warsaw, Heavy Ion Lab, Warsaw, Poland. Lund Univ, Dept Phys, Lund, Sweden. Hungarian Acad Sci, Inst Nucl Res, H-4001 Debrecen, Hungary. Royal Inst Technol, Stockholm, Sweden. Uppsala Univ, Dept Neutron Res, S-75105 Uppsala, Sweden. Ist Nazl Fis Nucl, Lab Nazl Legnaro, Padua, Italy. Univ Padua, Dipartimento Fis, I-35131 Padua, Italy. Ist Nazl Fis Nucl, Sez Padova, I-35100 Padua, Italy. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Univ Valencia, E-46003 Valencia, Spain. Inst Fis Corpuscular, Valencia, Spain. GSI, Darmstadt, Germany. Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Jozef Stefan Inst, Ljubljana, Slovenia. Soltan Inst Nucl Studies, Otwock, Poland. Chalmers, S-41296 Gothenburg, Sweden. Argonne Natl Lab, Chicago, IL USA. RP Palacz, M (reprint author), Univ Warsaw, Heavy Ion Lab, Warsaw, Poland. RI Dombradi, Zsolt/B-3743-2012; Lenzi, Silvia/I-6750-2012; Cederwall, Bo/M-3337-2014; Gadea, Andres/L-8529-2014; Algora, Alejandro/E-2960-2015; Palacz, Marcin/H-3713-2012; Napoli, Daniel R./D-9863-2012; OI Cederwall, Bo/0000-0003-1771-2656; Gadea, Andres/0000-0002-4233-1970; Algora, Alejandro/0000-0002-5199-1794; Napoli, Daniel R./0000-0002-8154-6958; Back, Torbjorn/0000-0003-1996-0805 NR 10 TC 2 Z9 2 U1 0 U2 0 PU WYDAWNICTWO UNIWERSYTETU JAGIELLONSKIEGO PI KRAKOW PA UL GRODZKA 26, KRAKOW, 31044, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD MAR PY 2001 VL 32 IS 3 BP 999 EP 1003 PG 5 WC Physics, Multidisciplinary SC Physics GA 422LN UT WOS:000168119900049 ER PT J AU Myers, WD Swiatecki, WJ AF Myers, WD Swiatecki, WJ TI At the extremes of nuclear charge and spin SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT XXXVth Zakopane School of Physics on Trends in Nuclear Physics CY SEP 05-13, 2000 CL ZAKOPANE, POLAND SP Polish State Comm Sci Res, PerkinElmer Instruments, Minist Natl Educ ID THOMAS-FERMI MODEL; SUPERHEAVY NUCLEI; BARRIERS; FUSION; MASSES AB Using scaling rules valid in the liquid drop model of nuclei, as well as universal rules associated with exchanges of stability in families of equilibrium configurations, we constructed closed formulae in terms of the atomic and mass numbers Z and A and the angular momentum L, which represent the properties of nuclei rotating synchronously (with;'rigid' moments of inertia), as calculated numerically using the Thomas-Fermi model of W.D. Myers, W.J. Swiatecki, Acta Phys. Pol. B27, 99 (1996); Nucl. Phys. A612, 249 (1997); Nucl. Phys. A601, 141 (1996). The formulae are accurate in the range of mass numbers where the transition to rapidly elongating triaxial 'Jacobi' shapes takes place. An improved set of formulae is also provided, which takes account of the decreased moments of inertia st low angular momenta. The formulae should be useful in guiding experimental searches for the Jacobi transition. In the second part of the paper we discuss qualitatively some aspects of the dynamics of nucleus-nucleus fusion, and outline a possible way of estimating cross-sections for the synthesis of superheavy nuclei. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Myers, WD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 24 TC 17 Z9 17 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD MAR PY 2001 VL 32 IS 3 BP 1033 EP 1047 PG 15 WC Physics, Multidisciplinary SC Physics GA 422LN UT WOS:000168119900055 ER PT J AU Hannachi, F Korichi, A Wilson, AN Lopez-Martens, A Rejumd, M Schuck, C Vieu, C Chmel, G Gorgen, A Hubel, H Rossbach, D Schonwasser, S Bergstrom, M Nyako, BM Timar, J Bazzacco, D Lunardi, S Rossi-Alvarez, C Bednarczyk, P Kintz, N Naguleswaran, S Astier, A Cullen, DM Sharpey-Schafer, JF Lauritsen, T Wadsworth, R AF Hannachi, F Korichi, A Wilson, AN Lopez-Martens, A Rejumd, M Schuck, C Vieu, C Chmel, G Gorgen, A Hubel, H Rossbach, D Schonwasser, S Bergstrom, M Nyako, BM Timar, J Bazzacco, D Lunardi, S Rossi-Alvarez, C Bednarczyk, P Kintz, N Naguleswaran, S Astier, A Cullen, DM Sharpey-Schafer, JF Lauritsen, T Wadsworth, R TI Collective excitations in the superdeformed well SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT XXXVth Zakopane School of Physics on Trends in Nuclear Physics CY SEP 05-13, 2000 CL ZAKOPANE, POLAND SP Polish State Comm Sci Res, PerkinElmer Instruments, Minist Natl Educ ID OCTUPOLE CORRELATIONS; BANDS; VIBRATIONS; STATES; HG-190; NUCLEI; DECAY AB Collective excitations are commonplace features in nuclei at normal deformation. It has been suggested that both in the ii similar to 190 and 150 superdeformed (SD) nuclei, collective vibrational states might occur in the same excitation energy range as quasi-particle and single-particle excitations. In particular, the large deformation associated with SD nuclei brings together orbitals from many spherical shells and leads to the close proximity of states with opposite parity, favouring octupole shape vibrations. However, to date, similar to 200 SD bands have been reported in more than 50 nuclei and in most cases, the excited SD bands have been interpreted as single or quasi-particle excitations. Only in very few cases, has the collective excitation scenario been suggested. Where are the collective states in SD nuclei? The question is particularly relevant in even-even A = 190 nuclei in which SD states are observed at lower rotational frequency and hence the additional influence of the pair gap makes the collective excitations more competitive with quasi-particle excitations. C1 CNRS, IN2P3, Ctr Spectrometrie Nucl & Spectrometrie Masse, F-91405 Orsay, France. Univ Paris 11, F-91405 Orsay, France. Univ York, Dept Phys, York YO10 5DD, N Yorkshire, England. Univ Bonn, Inst Strahlen & Kernphys, D-53115 Bonn, Germany. Niels Bohr Inst, DK-2100 Copenhagen O, Denmark. Inst Nucl Res, H-4001 Debrecen, Hungary. Dept Fis, Padua, Italy. Ist Nazl Fis Nucl, Sez Padova, I-35100 Padua, Italy. CNRS, IN2P3, IReS, F-67037 Strasbourg, France. Univ Strasbourg 1, F-67037 Strasbourg, France. IPN Lyon, CNRS, IN2P3, F-69622 Villeurbanne, France. Univ Lyon 1, F-69622 Villeurbanne, France. Univ Liverpool, Dept Phys, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Natl Accelerator Ctr, Cape Town, South Africa. Argonne Natl Lab, Argonne, IL 60439 USA. H Niewodniczanski Inst Nucl Phys, PL-31342 Krakow, Poland. RP Hannachi, F (reprint author), CNRS, IN2P3, Ctr Spectrometrie Nucl & Spectrometrie Masse, F-91405 Orsay, France. RI Naguleswaran, Sanjeev/A-4305-2013; OI Gorgen, Andreas/0000-0003-1916-9941; Wilson, Anna/0000-0001-6928-1689 NR 15 TC 0 Z9 0 U1 0 U2 1 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD MAR PY 2001 VL 32 IS 3 BP 1083 EP 1088 PG 6 WC Physics, Multidisciplinary SC Physics GA 422LN UT WOS:000168119900059 ER PT J AU Nowakowski, R Cwiok, S Nazarewicz, W Heenen, PH AF Nowakowski, R Cwiok, S Nazarewicz, W Heenen, PH TI Single-nucleon densities in superheavy nuclei SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT XXXVth Zakopane School of Physics on Trends in Nuclear Physics CY SEP 05-13, 2000 CL ZAKOPANE, POLAND SP Polish State Comm Sci Res, PerkinElmer Instruments, Minist Natl Educ ID RADII; SKINS AB Radii and diffuseness parameters of heavy and superheavy nuclei are analyzed for spherical and axially deformed shapes within the Skyrme-Hartree-Fock+BCS theory with zero-range pairing force. C1 Warsaw Univ Technol, Fac Phys, PL-00662 Warsaw, Poland. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Warsaw, Inst Theoret Phys, PL-00681 Warsaw, Poland. ULB, Serv Phys Nucl Theor, B-1050 Brussels, Belgium. RP Nowakowski, R (reprint author), Warsaw Univ Technol, Fac Phys, Koszykowa 75, PL-00662 Warsaw, Poland. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD MAR PY 2001 VL 32 IS 3 BP 1113 EP 1118 PG 6 WC Physics, Multidisciplinary SC Physics GA 422LN UT WOS:000168119900065 ER PT J AU Falge, E Baldocchi, D Olson, R Anthoni, P Aubinet, M Bernhofer, C Burba, G Ceulemans, R Clement, R Dolman, H Granier, A Gross, P Grunwald, T Hollinger, D Jensen, NO Katul, G Keronen, P Kowalski, A Lai, CT Law, BE Meyers, T Moncrieff, H Moors, E Munger, JW Pilegaard, K Rannik, U Rebmann, C Suyker, A Tenhunen, J Tu, K Verma, S Vesala, T Wilson, K Wofsy, S AF Falge, E Baldocchi, D Olson, R Anthoni, P Aubinet, M Bernhofer, C Burba, G Ceulemans, R Clement, R Dolman, H Granier, A Gross, P Grunwald, T Hollinger, D Jensen, NO Katul, G Keronen, P Kowalski, A Lai, CT Law, BE Meyers, T Moncrieff, H Moors, E Munger, JW Pilegaard, K Rannik, U Rebmann, C Suyker, A Tenhunen, J Tu, K Verma, S Vesala, T Wilson, K Wofsy, S TI Gap filling strategies for defensible annual sums of net ecosystem exchange SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article DE FLUXNET; EUROFLUX; AmeriFlux; eddy covariance; F-NEE; data filling; interpolation techniques ID WATER-VAPOR EXCHANGE; PONDEROSA PINE ECOSYSTEM; MODELING CARBON-DIOXIDE; DECIDUOUS FOREST; SOIL RESPIRATION; TALL VEGETATION; BEECH FOREST; FLUXES; VARIABILITY; ATMOSPHERE AB Heightened awareness of global change issues within both science and political communities has increased interest in using the global network of eddy covariance flux towers to more fully understand the impacts of natural and anthropogenic phenomena on the global carbon balance. Comparisons of net ecosystem exchange (F-NEE) responses are being made among biome types, phenology patterns, and stress conditions. The comparisons are usually performed on annual sums of F-NEE; however, the average data coverage during a year is only 65%. Therefore, robust and consistent gap filling methods are required. We review several methods of gap filling and apply them to data sets available from the EUROFLUX and AmeriFlux databases. The methods are based on mean diurnal variation (MDV), look-up tables LookUp, and nonlinear regressions (Regr.), and the impact of different gap filling methods on the annual sum of FNEE is investigated. The difference between annual F-NEE filled by MDV compared to F-NEE filled by Regr. ranged from -45 to +200 g C m(-2) per year (MDV-Regr.). Comparing LookUp and Regr. methods resulted in a difference (LookUp-Regr.) ranging from -30 to +150g Cm-2 per year. We also investigated the impact of replacing measurements at night, when turbulent mixing is insufficient. The nighttime correction for low friction velocities (u(*)) shifted annual F-NEE on average by +77 g C m(-2) per year, but in certain cases as much as +185 g C m-2 per year. Our results emphasize the need to standardize gap filling-methods for improving the comparability of flux data products from regional and global flux networks. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, SPM, Berkeley, CA 94704 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN USA. Oregon State Univ, Corvallis, OR 97331 USA. Fac Sci Agron Gembloux, Unite Phys, B-5030 Gembloux, Belgium. Tech Univ Dresden, IHM Meteorol, D-01737 Tharandt, Germany. Univ Nebraska, Sch Nat Resource Sci, Lincoln, NE 68583 USA. Univ Instelling Antwerp, Lab Plant Ecol, Dept Biol, B-2610 Wilrijk, Belgium. Univ Edinburgh, Inst Ecol & Resource Management, Edinburgh EH9 3JU, Midlothian, Scotland. Alterra, NL-6700 AA Wageningen, Netherlands. INRA, Unite Ecophysiol Forestiere, F-54280 Seichamps, France. USDA, Forest Serv, Durham, NH 03824 USA. Riso Natl Lab, Plant Biol & Biogeochem Dept, DK-4000 Roskilde, Denmark. Duke Univ, Sch Environm, Durham, NC 27708 USA. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. NOAA, ATDD, Oak Ridge, TN 37831 USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. Max Planck Inst Biogeochem, D-07701 Jena, Germany. Univ Bayreuth, D-95440 Bayreuth, Germany. Univ New Hampshire, Dept Nat Resources, Durham, NH 03824 USA. RP Falge, E (reprint author), Univ Calif Berkeley, SPM, Berkeley, CA 94704 USA. RI Pilegaard, Kim/I-7137-2013; Meyers, Tilden/C-6633-2016; Ceulemans, Reinhart/F-2109-2016; Munger, J/H-4502-2013; Burba, George/G-9991-2014; Vesala, Timo/C-3795-2017; Katul, Gabriel/A-7210-2008; Kowalski, Andrew/A-7515-2008; Baldocchi, Dennis/A-1625-2009; Hollinger, David/G-7185-2012; Moors, Eddy/J-5165-2012 OI Dolman, A.J./0000-0003-0099-0457; Pilegaard, Kim/0000-0002-5169-5717; Munger, J/0000-0002-1042-8452; Burba, George/0000-0003-2095-0057; Vesala, Timo/0000-0002-4852-7464; Law, Beverly/0000-0002-1605-1203; Katul, Gabriel/0000-0001-9768-3693; Kowalski, Andrew/0000-0001-9777-9708; Baldocchi, Dennis/0000-0003-3496-4919; Moors, Eddy/0000-0003-2309-2887 NR 49 TC 881 Z9 1011 U1 17 U2 205 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD MAR 1 PY 2001 VL 107 IS 1 BP 43 EP 69 DI 10.1016/S0168-1923(00)00225-2 PG 27 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 406AE UT WOS:000167192100003 ER PT J AU Falge, E Baldocchi, D Olson, R Anthoni, P Aubinet, M Bernhofer, C Burba, G Ceulemans, G Clement, R Dolman, H Granier, A Gross, P Grunwald, T Hollinger, D Jensen, NO Katul, G Keronen, P Kowalski, A Lai, CT Law, BE Meyers, T Moncrieff, J Moors, E Munger, JW Pilegaard, K Rannik, U Rebmann, C Suyker, A Tenhunen, J Tu, K Verma, S Vesala, T Wilson, K Wofsy, S AF Falge, E Baldocchi, D Olson, R Anthoni, P Aubinet, M Bernhofer, C Burba, G Ceulemans, G Clement, R Dolman, H Granier, A Gross, P Grunwald, T Hollinger, D Jensen, NO Katul, G Keronen, P Kowalski, A Lai, CT Law, BE Meyers, T Moncrieff, J Moors, E Munger, JW Pilegaard, K Rannik, U Rebmann, C Suyker, A Tenhunen, J Tu, K Verma, S Vesala, T Wilson, K Wofsy, S TI Gap filling strategies for long term energy flux data sets SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article DE FLUXNET; EUROFLUX; AmeriFlux; eddy covariance; latent heat; sensible heat; data filling; interpolation techniques ID EDDY-COVARIANCE; CARBON; EXCHANGE; FOREST AB At present a network of over 100 field sites are measuring carbon dioxide, water vapor and sensible heat fluxes between the biosphere and atmosphere, on a nearly continuous basis. Gaps in the long term measurements of evaporation and sensible heat flux must be filled before these data can be used for hydrological and meteorological applications. We adapted methods of gap filling for NEE (net ecosystem exchange of carbon) to energy fluxes and applied them to data sets available from the EUROFLUX and AmeriFlux eddy covariance databases. The average data coverage for the sites selected was 69% and 75% for latent heat (lambdaE) and sensible heat (H). The methods were based on mean diurnal variations (half-hourly binned means of fluxes based on previous and subsequent days, MDV) and look-up tables for fluxes during assorted meteorological conditions (LookUp), and the impact of different gap filling methods on the annual sum of lambdaE and H is investigated. The difference between annual lambdaE filled by MDV and lambdaE filled by LookUp ranged from -120 to 210 MJ m(-2) per year, i.e. -48 to +86 mm per year, or -13 to +39% of the annual sum. For annual sums of H differences between - 140 and +140 MJ m(-2) per year or -12 to +19% of the annual sum were found. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, ESPM, Berkeley, CA 94704 USA. Univ New Hampshire, Dept Nat Resources, Durham, NH 03824 USA. Univ Bayreuth, D-95440 Bayreuth, Germany. Max Planck Inst Biogeochem, D-07701 Jena, Germany. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. NOAA, ATDD, Oak Ridge, TN 37831 USA. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Duke Univ, Sch Environm, Durham, NC 27708 USA. Riso Natl Lab, Platn Biol & Biogeochem Dept, DK-4000 Roskilde, Denmark. US Forest Serv, USDA, Durham, NH 03824 USA. INRA, Unite Ecophysiol Forestiere, F-54280 Seichamps, France. Alterra, NL-6700 AA Wageningen, Netherlands. Univ Edinburgh, Inst Ecol & Resource Management, Edinburgh EH9 3JU, Midlothian, Scotland. Univ Instelling Antwerp, Dept Biol, Plant Biol Lab, B-2610 Wilrijk, Belgium. Univ Nebraska, Sch Nat Resouce Sci, Lincoln, NE 68583 USA. Tech Univ Dresden, IHM Meteorol, D-01737 Tharandt, Germany. Fac Sci Agron Gembloux, Unite Phys, B-5030 Gembloux, Belgium. Oregon State Univ, Corvallis, OR 97331 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Falge, E (reprint author), Univ Calif Berkeley, ESPM, Berkeley, CA 94704 USA. RI Hollinger, David/G-7185-2012; Moors, Eddy/J-5165-2012; Pilegaard, Kim/I-7137-2013; Meyers, Tilden/C-6633-2016; Munger, J/H-4502-2013; Burba, George/G-9991-2014; Vesala, Timo/C-3795-2017; Katul, Gabriel/A-7210-2008; Kowalski, Andrew/A-7515-2008; Baldocchi, Dennis/A-1625-2009 OI Moors, Eddy/0000-0003-2309-2887; Pilegaard, Kim/0000-0002-5169-5717; Munger, J/0000-0002-1042-8452; Burba, George/0000-0003-2095-0057; Vesala, Timo/0000-0002-4852-7464; Law, Beverly/0000-0002-1605-1203; Katul, Gabriel/0000-0001-9768-3693; Kowalski, Andrew/0000-0001-9777-9708; Baldocchi, Dennis/0000-0003-3496-4919 NR 12 TC 261 Z9 317 U1 4 U2 77 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD MAR 1 PY 2001 VL 107 IS 1 BP 71 EP 77 DI 10.1016/S0168-1923(00)00235-5 PG 7 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 406AE UT WOS:000167192100004 ER PT J AU Narula, CK Nakouzi, SR Wu, RW Goralski, CT Allard, LF AF Narula, CK Nakouzi, SR Wu, RW Goralski, CT Allard, LF TI Evaluation of sol-gel processed BaO center dot nAl(2)O(3) material as NOx traps SO AICHE JOURNAL LA English DT Article ID MOLECULAR-SIEVES; CATALYSTS AB Among various strategies to treat NOx, trapping is considered an economical, consumer transparent approach for gasoline engines. The conventional NOx traps are based on alkaline-earth metal impregnated alumina. These traps work well, but cannot sustain their NOx trapping efficiency after repeated exposure to high temperatures during regeneration. In search of thermally stable materials, a series of sol-gel processed BaO . nAl(2)O(3) (n=1,4,6) materials including BaO . 6Al(2)O(3) molecular sieves were synthesized and evaluated as NOx traps using simulated exhaust at a 25,000 h(-1) space velocity. Changes in structure and surface properties occurring on thermal treatment of sol-gel processed BaO . nAl(2)O(3) materials significantly affect the NO, trapping efficiency of these materials. Among these materials, sol-gel processed and precious metal impregnated BaO . 6Al(2)O(3) powder offers the optimum combination of thermal stability and NO, trapping efficiency. We deposited this powder on a honeycomb substrate, impregnated it with 2% Pt and 0.4% Rh, and reevaluated it. The NO, trapping efficiency of this catalyst is 95% (cf: 75% for the powder) at 310 degreesC. Our data on Pt/BaO . 6Al(2)O(3) also suggest that the optimum lean cycle length for this class of NOx traps is I min. The efficiency of NOx traps decreases rapidly and falls in 10-20% range with an alternating 5 min ban cycle and I min rich cycle. C1 Ford Motor Co, Dept Chem, Dearborn, MI 48121 USA. Ford Motor Co, Dept Chem Engn, Dearborn, MI 48121 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Narula, CK (reprint author), Ford Motor Co, Dept Chem, Dearborn, MI 48121 USA. NR 20 TC 9 Z9 9 U1 0 U2 3 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 3 PARK AVE, NEW YORK, NY 10016-5901 USA SN 0001-1541 J9 AICHE J JI AICHE J. PD MAR PY 2001 VL 47 IS 3 BP 744 EP 753 DI 10.1002/aic.690470320 PG 10 WC Engineering, Chemical SC Engineering GA 411TF UT WOS:000167514800019 ER PT J AU Chisolm, ED AF Chisolm, ED TI Generalizing the Heisenberg uncertainty relation SO AMERICAN JOURNAL OF PHYSICS LA English DT Article AB The proof of the Heisenberg uncertainty relation is modified to produce two improvements: (a) The resulting inequality is stronger because it includes the covariance between the two observables, and (b) the proof lifts certain restrictions on the state to which the relation is applied, increasing its generality. The restrictions necessary for the standard inequality to apply are not widely known, and they are discussed in detail. The classical analog of the Heisenberg relation is also derived, and the two are compared. Finally, the modified relation is used to address the apparent paradox that eigenfunctions of the z component of angular momentum L-z do not satisfy the phi -L-z Heisenberg relation; the resolution is that the restrictions mentioned above make the usual inequality inapplicable to these states. The modified relation does apply, however, and it is shown to be consistent with explicit calculations. (C) 2001 American Association of Physics Teachers. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chisolm, ED (reprint author), Univ Calif Los Alamos Natl Lab, T-1,MS B221, Los Alamos, NM 87545 USA. NR 19 TC 10 Z9 10 U1 2 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD MAR PY 2001 VL 69 IS 3 BP 368 EP 371 DI 10.1119/1.1317561 PG 4 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 404RD UT WOS:000167113700026 ER PT J AU Volkow, ND Chang, L Wang, GJ Fowler, JS Leonido-Yee, M Franceschi, D Sedler, MJ Gatley, SJ Hitzemann, R Ding, YS Logan, J Wong, C Miller, EN AF Volkow, ND Chang, L Wang, GJ Fowler, JS Leonido-Yee, M Franceschi, D Sedler, MJ Gatley, SJ Hitzemann, R Ding, YS Logan, J Wong, C Miller, EN TI Association of dopamine transporter reduction with psychomotor impairment in methamphetamine abusers SO AMERICAN JOURNAL OF PSYCHIATRY LA English DT Article ID POSITRON-EMISSION-TOMOGRAPHY; PARKINSONS-DISEASE; INDUCED NEUROTOXICITY; C-11 WIN-35,428; PET LIGAND; BRAIN; BINDING; USERS AB Objective: Methamphetamine is a popular and highly addictive drug of abuse that has raised concerns because it has been shown in laboratory animals to be neurotoxic to dopamine terminals. The authors evaluated if similar changes occur in humans and assessed if they were functionally significant. Method: Positron emission tomography scans following administration of [C-11]d-threo-methyl phenidate (a dopamine transporter ligand) measured dopamine transporter levels (a marker of dopamine cell terminals) in the brains of 15 detoxified methamphetamine abusers and 18 comparison subjects. Neuropsychological tests were also performed to assess motor and cognitive function. Results: Methamphetamine abusers showed significant dopamine transporter reduction in the striatum (mean differences of 27.8% in the caudate and 21.1% in the putamen) relative to the comparison subjects; this reduction was evident even in abusers who had been detoxified for at least 11 months. Dopamine transporter reduction was associated with motor slowing and memory impairment. Conclusions: These results provide evidence that methamphetamine at dose levels taken by human abusers of the drug leads to dopamine transporter reduction that is associated with motor and cognitive impairment. These results emphasize the urgency of alerting clinicians and the public of the long-term changes that methamphetamine can induce in the human brain. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Los Angeles, Dept Neurol, Los Angeles, CA 90024 USA. Univ Calif Los Angeles, Dept Psychiat, Los Angeles, CA 90024 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Bldg 490,POB 5000, Upton, NY 11973 USA. FU NCRR NIH HHS [RR-10710]; NIDA NIH HHS [DA-00280, DA-7092-01] NR 33 TC 550 Z9 559 U1 6 U2 40 PU AMER PSYCHIATRIC PRESS, INC PI WASHINGTON PA 1400 K ST, N W, STE 1101, WASHINGTON, DC 20005 USA SN 0002-953X J9 AM J PSYCHIAT JI Am. J. Psychiat. PD MAR PY 2001 VL 158 IS 3 BP 377 EP 382 DI 10.1176/appi.ajp.158.3.377 PG 6 WC Psychiatry SC Psychiatry GA 408JL UT WOS:000167323000007 PM 11229977 ER PT J AU Volkow, ND Chang, L Wang, GJ Fowler, JS Franceschi, D Sedler, MJ Gatley, SJ Hitzemann, R Ding, YS Wong, C Logan, J AF Volkow, ND Chang, L Wang, GJ Fowler, JS Franceschi, D Sedler, MJ Gatley, SJ Hitzemann, R Ding, YS Wong, C Logan, J TI Higher cortical and lower subcortical metabolism in detoxified methamphetamine abusers SO AMERICAN JOURNAL OF PSYCHIATRY LA English DT Article ID HIGH-DOSE METHAMPHETAMINE; PROGRESSIVE SUPRANUCLEAR PALSY; POSITRON-EMISSION-TOMOGRAPHY; CEREBRAL GLUCOSE-UTILIZATION; RAT SOMATOSENSORY CORTEX; PARKINSONS-DISEASE; BRAIN; DOPAMINE; PET; DEGENERATION AB Objective: Methamphetamine has raised concerns because it may be neurotoxic to the human brain. Although prior work has focused primarily on the effects of methamphetamine on dopamine cells, there is evidence that other neuronal types are affected. The authors measured regional brain glucose metabolism, which serves as a marker of brain function, to assess if there is evidence of functional changes in methamphetamine abusers in regions other than those innervated by dopamine cells. Method: Fifteen detoxified methamphetamine abusers and 21 comparison subjects underwent positron emission tomography following administration of [F-18]fluorodeoxyglucose. Results: Whole brain metabolism in the methamphetamine abusers was 14% higher than that of comparison subjects; the differences were most accentuated in the parietal cortex (20%). After normalization for whole brain metabolism, methamphetamine abusers exhibited significantly lower metabolism in the thalamus (17% difference) and striatum (where the differences were larger for the caudate [12%] than for the putamen [6%]). Statistical parametric mapping analyses corroborated these findings, revealing higher metabolism in the parietal cortex and lower metabolism in the thalamus and striatum of methamphetamine abusers. Conclusions: The fact that the parietal cortex is a region devoid of any significant dopaminergic innervation suggests that the higher metabolism seen in this region in the methamphetamine abusers is the result of methamphetamine effects in circuits other than those modulated by dopamine. In addition, the lower metabolism in the striatum and thalamus (major outputs of dopamine signals into the cortex) is likely to reflect the functional consequence of methamphetamine in dopaminergic circuits. These results provide evidence that, in humans, methamphetamine abuse results in changes in function of dopamine- and nondopamine-innervated brain regions. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Los Angeles, Dept Neurol, Los Angeles, CA 90024 USA. Univ Calif Los Angeles, Dept Psychiat, Los Angeles, CA 90024 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Bldg 490,POB 5000, Upton, NY 11973 USA. FU NCRR NIH HHS [RR-10710]; NIDA NIH HHS [DA-00280, DA-7092-01] NR 47 TC 146 Z9 156 U1 1 U2 2 PU AMER PSYCHIATRIC PRESS, INC PI WASHINGTON PA 1400 K ST, N W, STE 1101, WASHINGTON, DC 20005 USA SN 0002-953X J9 AM J PSYCHIAT JI Am. J. Psychiat. PD MAR PY 2001 VL 158 IS 3 BP 383 EP 389 DI 10.1176/appi.ajp.158.3.383 PG 7 WC Psychiatry SC Psychiatry GA 408JL UT WOS:000167323000008 PM 11229978 ER PT J AU Rosso, KM Rustad, JR AF Rosso, KM Rustad, JR TI Structures and energies of AlOOH and FeOOH polymorphs from plane wave pseudopotential calculations SO AMERICAN MINERALOGIST LA English DT Article ID CRYSTAL-STRUCTURE REFINEMENT; HYDROLYSIS; AKAGANEITE; SURFACES; CR(III); OXIDE AB Plane wave pseudopotential methods are used to investigate the structures and total energies of AlOOH and FeOOH in the five canonical oxyhydroxide structures: diaspore (goethite), boehmite (lepidocrocite), akaganeite, guyanaite, and grimaldiite. The local density approximation was used in conjunction with ultrasoft pseudopotentials in full optimizations of both AlOOH and FeOOH in each of these structures. Structures are in reasonably good agreement with experiment, with lattice parameters and bond lengths within 3% of experimental values. Neither AlOOH nor FeOOH have been identified in the grimaldiite or guyanaite structures, however we find that total energies for AlOOH and FeOOH in these structures are comparable to or lower than the total energies of the commonly observed polymorphs (with the exception of FeOOH in the grimaldiite structure, which is anomalously high energy). Estimated zero-point energy corrections do not alter this result. For diaspore and boehmite, we also provide calculations using the generalized gradient approximation and norm-conserving pseudopotentials to assess the extent to which the results depend on the particular level of theory used. We find that diaspore is predicted to have a lower energy, consistent with experimental observation, using all but one methodological combination where the generalized gradient approximation is combined with ultrasoft pseudopotentials. Thus, although one may reasonably conclude that the differences in total energies of the various (Al,Fe)oxyhydroxide polymorphs are small, current electronic structure methods do not appear to be fully capable of accurately resolving these small differences. These findings provide further confirmation that the structures of oxyhydroxide polymorphs and surface precipitates are more likely to be a function of kinetics than of intrinsic lattice stability. C1 Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Rosso, KM (reprint author), Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. NR 32 TC 35 Z9 36 U1 2 U2 15 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1015 EIGHTEENTH ST, NW SUITE 601, WASHINGTON, DC 20036 USA SN 0003-004X J9 AM MINERAL JI Am. Miner. PD MAR PY 2001 VL 86 IS 3 BP 312 EP 317 PG 6 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 408TN UT WOS:000167343900014 ER PT J AU Gourley, PL Sasaki, DY AF Gourley, PL Sasaki, DY TI Biocavity lasers SO AMERICAN SCIENTIST LA English DT Article ID FLOW-CYTOMETRY; PROTEIN; DNA C1 Sandia Natl Labs, Biomol Mat & Interfaces Dept, Albuquerque, NM 87185 USA. RP Gourley, PL (reprint author), Sandia Natl Labs, Biomol Mat & Interfaces Dept, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 7 Z9 7 U1 0 U2 4 PU SIGMA XI-SCI RES SOC PI RES TRIANGLE PK PA PO BOX 13975, RES TRIANGLE PK, NC 27709 USA SN 0003-0996 J9 AM SCI JI Am. Scientist PD MAR-APR PY 2001 VL 89 IS 2 BP 152 EP 159 PG 8 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 400YH UT WOS:000166899900014 ER PT J AU Hirsch, RF AF Hirsch, RF TI Analytical chemistry and the life sciences SO ANALYTICAL CHEMISTRY LA English DT Editorial Material C1 US DOE, Div Med Sci, Washington, DC 20585 USA. RP Hirsch, RF (reprint author), US DOE, Div Med Sci, Washington, DC 20585 USA. NR 0 TC 0 Z9 0 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 1 PY 2001 VL 73 IS 5 BP 117A EP 117A DI 10.1021/ac012399v PG 1 WC Chemistry, Analytical SC Chemistry GA 407QX UT WOS:000167283200001 PM 11289420 ER PT J AU Ngola, SM Fintschenko, Y Choi, WY Shepodd, TJ AF Ngola, SM Fintschenko, Y Choi, WY Shepodd, TJ TI Conduct-as-cast polymer monoliths as separation media for capillary electrochromatography SO ANALYTICAL CHEMISTRY LA English DT Article ID INDUCED PHASE-SEPARATION; PERFORMANCE LIQUID-CHROMATOGRAPHY; MACROPOROUS EPOXY NETWORKS; STATIONARY PHASES AB We have developed porous polymer monoliths (PPMs) that are versatile and robust reversed-phase chromatography media. The PPMs are cast-to-shape, UV-cured polymers that form uniform packings within pretreated glass capillaries and fused-silica chips,No applied pressure is ever needed to flush the PPMs since they support electroosmotic flow as cast. Such characteristics make the PPMs useful for chip-based devices: Our results show efficiencies greater than or equal to 150 000 plates/m for both capillary and chip-based separations of polycpclic aromatic hydrocarbons. By changing the monomers, the hydrophobicity of the polymers, and the direction of the electroosmotic now can be altered without degrading chromatographic performance. We describe here the development of these acrylate-based materials along with both physical and chromatographic characterization. C1 Sandia Natl Labs, Dept Chem Mat, Livermore, CA 94551 USA. Sandia Natl Labs, Chem & Radiat Detect Lab, Livermore, CA 94551 USA. RP Shepodd, TJ (reprint author), Sandia Natl Labs, Dept Chem Mat, Livermore, CA 94551 USA. NR 26 TC 106 Z9 108 U1 1 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 1 PY 2001 VL 73 IS 5 BP 849 EP 856 DI 10.1021/ac000839x PG 8 WC Chemistry, Analytical SC Chemistry GA 407QX UT WOS:000167283200010 PM 11289427 ER PT J AU Roberts, KP Jankowiak, R Small, GJ AF Roberts, KP Jankowiak, R Small, GJ TI High-performance liquid chromatography interfaced with fluorescence line-narrowing spectroscopy for on-line analysis SO ANALYTICAL CHEMISTRY LA English DT Article ID POLYACRYLAMIDE-GEL ELECTROPHORESIS; THIN-LAYER CHROMATOGRAPHY; CAPILLARY-ELECTROPHORESIS; DNA-ADDUCTS; SPECTRAL CHARACTERIZATION; DEOXYADENOSINE ADDUCTS; ONLINE IDENTIFICATION; MASS-SPECTROMETRY; SEPARATION; ANALYTES AB We have demonstrated, for the first time, that highperformance liquid chromatography (HPLC) can be interfaced with fluorescence line-narrowing spectroscopy (FLNS) for on-line identification and characterization of analytes. interfacing centered primarily on the design and construction of a novel liquid helium cryostat that accommodates variable-sized quartz tubes/capillaries suitable for HPLC as well as capillary electrophoresis/electrochromatography. In addition to the high spectral resolution afforded by FLNS, analying the separated components at 4.2 K minimizes photodegradation from the excitation source and provides indefinite detection times for signal averaging. The proof-of-principle for the HPLC-FLNS system is first demonstrated with a mixture of four structurally similar polycyclic aromatic hydrocarbons and then applied to the analysis of DNA adducts from mouse skin exposed to the carcinogen dibenzo[a,l]pyrene, With femtomole detection limits, HPLC-FLNS can be used for real-world analyses of complex mixtures. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Small, GJ (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. NR 29 TC 9 Z9 9 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 1 PY 2001 VL 73 IS 5 BP 951 EP 956 DI 10.1021/ac0008789 PG 6 WC Chemistry, Analytical SC Chemistry GA 407QX UT WOS:000167283200024 PM 11289441 ER PT J AU Wang, N Budde, WL AF Wang, N Budde, WL TI Determination of carbamate, urea, and thiourea pesticides and herbicides in water SO ANALYTICAL CHEMISTRY LA English DT Article ID CHROMATOGRAPHY MASS-SPECTROMETRY; LIQUID-CHROMATOGRAPHY; ELECTROSPRAY-IONIZATION; MISSISSIPPI RIVER; UNITED-STATES AB Microbore liquid chromatography and positive ion electrospray mass spectrometry are applied to the determination of 16 carbamate, urea, and thiourea pesticides and herbicides in water. The electrospray mass spectra of the analytes were measured and are discussed and mobile-phase matrix effects were evaluated. Analyte positive ion abundances are generally inversely related to the concentration of acetic acid in the acetonitrile-water mobile phase in the range of 0.001 - 0.1% (v/v) acetic acid. Using an internal standard for quantitative analyses and no acid in the mobile phase, retention time precision, peak width precision, concentration measurement precision, mean recoveries, and instrument detection limits were determined in reagent water. The 16 analytes were also measured in fortified environmental water samples from a recreational lake, a groundwater well, a cistern, a farm pond, and drinking water. These measurements were at 5 ng/mL of each analyte, which is within the range expected for environmental pesticide and herbicide contaminants, The analytes were separated from the environmental water matrixes with an on-line extraction and concentration to provide rapid sample analyses without a slow off-line liquid-liquid or liquid-solid-liquid extraction and extract concentration. Recoveries of 12 of the analytes from 4 environmental water samples were in the range of 75-124% with relative standard deviations in the range of 11-16%. C1 US EPA, Off Res & Dev, Natl Exposure Res Lab, Cincinnati, OH 45268 USA. Oak Ridge Inst Sci & Educ, Cincinnati, OH 45268 USA. RP Budde, WL (reprint author), US EPA, Off Res & Dev, Natl Exposure Res Lab, 26 W MartinL King Dr, Cincinnati, OH 45268 USA. NR 15 TC 57 Z9 57 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 1 PY 2001 VL 73 IS 5 BP 997 EP 1006 DI 10.1021/ac0010734 PG 10 WC Chemistry, Analytical SC Chemistry GA 407QX UT WOS:000167283200030 PM 11289447 ER PT J AU Laskin, A Cowin, JP AF Laskin, A Cowin, JP TI Automated single particle SEM/EDX analysis of submicrometer particles down to 0.1 mu m SO ANALYTICAL CHEMISTRY LA English DT Article ID ELECTRON-PROBE MICROANALYSIS; INDIVIDUAL AEROSOL-PARTICLES; ATMOSPHERIC AEROSOLS; WINDOW EPMA; SEA-SALT; ELEMENTS; SULFATE AB Typically single-particle SEM/EDX analysis of aerosols is done on polycarbonate filters or solid carbon substrates, This has led to a widespread conclusion that EDX provides poor information on carbon, oxygen, and nitrogen content of a particle and usually could not go below 0.5-mum particles. We show that use of grid-supported carbon films of 15-25-nm thickness gives exceptionally low background in the SEM/EDX analysis and allows satisfied automated analysis of particles down to 0.1-mum size, including detection of low-Z elements. In this work, six laboratory-generated 0.1-2-mum aerosols were tested for their elemental composition. The EDX analysis yields reasonably accurate quantitative results featuring all the elements present in the tested compounds, namely, C, O, N, Na, S, Al, Si, and Cl, Furthermore, the carbon film has very low backscattered electron (BSE) yield compared to that from the particle, so in the BSE mode the particle image is seen with celery high contrast, This greatly improves quality and speed of the automated mapping of particles by SEM prior to EDX analysis. C1 Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Laskin, A (reprint author), Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, POB 999,MSIN K8-88, Richland, WA 99352 USA. RI Laskin, Alexander/I-2574-2012 OI Laskin, Alexander/0000-0002-7836-8417 NR 28 TC 57 Z9 60 U1 5 U2 43 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 1 PY 2001 VL 73 IS 5 BP 1023 EP 1029 DI 10.1021/ac0009604 PG 7 WC Chemistry, Analytical SC Chemistry GA 407QX UT WOS:000167283200033 PM 11289412 ER PT J AU Singh, AK Cummings, EB Throckmorton, DJ AF Singh, AK Cummings, EB Throckmorton, DJ TI Fluorescent liposome flow markers for microscale particle image velocimetry SO ANALYTICAL CHEMISTRY LA English DT Article ID ELECTROOSMOTIC FLOW; CAPILLARIES; CHIP AB Unilamellar liposomes carrying both encapsulated and surface-immobilized fluorophores have been synthesized as novel fluorescent markers to image flow profiles in microfabricated structures. The unilamellar liposomes were made with phospholipids and cholesterol by extrusion through a polycarbonate membrane, They contained carboxyfluorescein in the aqueous core and fluorescein-labeled lipids in the bilayer to render them both a surface and volume fluorescer, maximizing their fluorescence intensity. The lipid composition was chosen to impart a net negative charge to liposomes to minimize self-aggregation as well as interaction with negatively charged glass surfaces of the channels. These liposomes were monodisperse (mean diameter 283 nm), neutrally buoyant, and hydrophilic and exhibited no adsorption on glass surfaces. Unlike polystyrene spheres, they were readily broken up by surfactants, thereby allowing for easy and complete removal from microfluidic channels. The fluorescent liposomes were used to investigate pressure-driven now in an offset cross intersection in a microfluidic chip and provided images with excellent signal-to-noise ratio. A novel computational scheme that is particularly suitable for analyzing particle-image velocimetry data in micrometer-scale flow channels was employed to analyze the images. These liposomes are easily synthesized and can be custom-made for various applications to offer a broad range of surface and volume characteristics such as charge, size, and surface chemistry. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Singh, AK (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. NR 26 TC 35 Z9 36 U1 2 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 1 PY 2001 VL 73 IS 5 BP 1057 EP 1061 DI 10.1021/ac001159x PG 5 WC Chemistry, Analytical SC Chemistry GA 407QX UT WOS:000167283200039 PM 11289418 ER PT J AU Spriggs, GD Busch, RD Campbell, JM AF Spriggs, GD Busch, RD Campbell, JM TI Calculation of the delayed neutron effectiveness factor using ratios of k-eigenvalues SO ANNALS OF NUCLEAR ENERGY LA English DT Article AB In this work, we derive from the transport equation the effectiveness factor used in the beta (eff) calculation and show that, to a first approximation. it is equal to the ratio of two k-eigenvalues: one obtained using the total neutron spectrum, and the other obtained using only the delayed neutron spectrum. This method, which we shall refer to as the k-ratio method, has been tested using several different types of reactor systems. In this report we present the results for the simplest of these systems the Godiva-I assembly at the Los Alamos Critical Experiments Facility (LACEF). Although the method is not exact, it does yield results that are remarkably close to the traditional adjoint-weighting method. (C) 2001 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. RP Spriggs, GD (reprint author), Univ Calif Los Alamos Natl Lab, MS F664, Los Alamos, NM 87545 USA. NR 12 TC 15 Z9 17 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0306-4549 J9 ANN NUCL ENERGY JI Ann. Nucl. Energy PD MAR PY 2001 VL 28 IS 5 BP 477 EP 487 DI 10.1016/S0306-4549(00)00064-5 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 401JB UT WOS:000166923500007 ER PT J AU Nolen, SD Spriggs, GD AF Nolen, SD Spriggs, GD TI Estimation of the neutron chain-length distribution in subcritical systems using a point Monte Carlo code SO ANNALS OF NUCLEAR ENERGY LA English DT Article DE neutron chain length; subcritical system; Monte Carlo AB A point Monte Carlo code has been developed that simulates the evolution of prompt fission chains in subcritical systems. From this simulation, a numerical estimate of the neutron chain-length distribution as a function of k(eff) has been obtained for subcritical systems. We also discuss the importance of the detector efficiency in performing a successful neutron noise measurement in highly subcritical systems. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Spriggs, GD (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS F661, Los Alamos, NM 87545 USA. NR 4 TC 3 Z9 5 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0306-4549 J9 ANN NUCL ENERGY JI Ann. Nucl. Energy PD MAR PY 2001 VL 28 IS 5 BP 509 EP 512 DI 10.1016/S0306-4549(00)00059-1 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 401JB UT WOS:000166923500010 ER PT J AU Davison, BH Finkelstein, M AF Davison, BH Finkelstein, M TI Introduction to the Proceedings of the Twenty-Second Symposium on Biotechnology for Fuels and Chemicals SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Editorial Material C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Davison, BH (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Davison, Brian/D-7617-2013 OI Davison, Brian/0000-0002-7408-3609 NR 21 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP III EP VII PG 5 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100001 ER PT J AU Tucker, MP Nguyen, QA Eddy, FP Kadam, KL Gedvilas, LM Webb, JD AF Tucker, MP Nguyen, QA Eddy, FP Kadam, KL Gedvilas, LM Webb, JD TI Fourier transform infrared quantitative analysis of sugars and lignin in pretreated softwood solid residues SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 22nd Symposium on Biotechnology for Fuels and Chemicals CY MAY 07-11, 2000 CL GATLINBURG, TENNESSEE SP US DOE, Off Fuels Dev, Oak Ridge Natl Lab, Off Ind Technologies, Agr & Chem Ind, Natl Renewable Energy Lab, Idaho Natl Engn & Envrionm Lab, Lockheed Martin Energy Res, Amer Chem Soc, Div Biochem Technol, Royal Nedalco BV, Raphael Katzen Associates, Tate & Lyle (AE Staley Mfg Co), Natl Resources Canada, Dupont Co, Iogen Corp, Corn Refiners Assoc Inc, Dow Chem Co, Argonne Natl Lab, NIST, Tembec Inc, Pure Energy Corp, TN Valley Authority, Public Power Inst, Cargill Inc DE fourier transform infrared; biomass; softwood; dilute-acid pretreatment; acid hydrolysis ID FTIR SPECTROSCOPY; SPECTROMETRY; DRIFT AB Hydrolysates were obtained from dilute sulfuric acid pretreatment of whole-tree softwood forest thinnings and softwood sawdust. Mid-infrared (IR) spectra were obtained on sample sets of wet washed hydrolysates, and 45 degreesC vacuum-dried washed hydrolysates, using a Fourier transform infrared (FTIR) spectrophotometer equipped with a diamond-composite attenuated total reflectance (ATR) cell. Partial least squares (PLS) analysis of spectra from each sample set was performed. Regression analyses for sugar components and lignin were generated using results obtained from standard wet chemical and high-performance liquid chromatography methods. The correlation coefficients of the predicted and measured values were >0.9. The root mean square standard error of the estimate for each component in the residues c vas generally within 2 wt% of the measured value except where reported in the tables. The PLS regression analysis of the wet washed solids was similar to the PLS regression analysis on the 45 degreesC vacuum-dried sample set. The FTIR-ATR technique allows mid-TR spectra to be obtained in a few minutes from wet washed or dried washed pretreated biomass solids. The prediction of the solids composition bf an unknown washed pretreated solid is very rapid once the PLS method has been calibrated with known standard solid residues. C1 Natl Renewable Energy Lab, Biotechnol Ctr Fuels & Chem, Golden, CO 80401 USA. Natl Renewable Energy Lab, Ctr Measurements & Characterizat, Golden, CO 80401 USA. RP Tucker, MP (reprint author), Natl Renewable Energy Lab, Biotechnol Ctr Fuels & Chem, 1617 Cole Blvd, Golden, CO 80401 USA. NR 20 TC 25 Z9 25 U1 0 U2 8 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 51 EP 61 DI 10.1385/ABAB:91-93:1-9:51 PG 11 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100006 PM 11963880 ER PT J AU Vinzant, TB Adney, WS Decker, SR Baker, JO Kinter, MT Sherman, NE Fox, JW Himmel, ME AF Vinzant, TB Adney, WS Decker, SR Baker, JO Kinter, MT Sherman, NE Fox, JW Himmel, ME TI Fingerprinting Trichoderma reesei hydrolases in a commerical cellulase preparation SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 22nd Symposium on Biotechnology for Fuels and Chemicals CY MAY 07-11, 2000 CL GATLINBURG, TENNESSEE SP US DOE, Off Fuels Dev, Oak Ridge Natl Lab, Off Ind Technologies, Agr & Chem Ind, Natl Renewable Energy Lab, Idaho Natl Engn & Envrionm Lab, Lockheed Martin Energy Res, Amer Chem Soc, Div Biochem Technol, Royal Nedalco BV, Raphael Katzen Associates, Tate & Lyle (AE Staley Mfg Co), Natl Resources Canada, Dupont Co, Iogen Corp, Corn Refiners Assoc Inc, Dow Chem Co, Argonne Natl Lab, NIST, Tembec Inc, Pure Energy Corp, TN Valley Authority, Public Power Inst, Cargill Inc DE cellulase; Trichoderma reesei; two-dimensional gel electrophoresis; liquid chromatography-mass spectrometry/mass spectrometry ID EXPRESSION; CLONING; GENE AB Polysaccharide degrading enzymes from commercial T, reesei broth have been subjected to "fingerprint" analysis by high-resolution 2-D gel electrophoresis. Forty-five spots from 11 x 25 cm Pharmacia gels have been analyzed by LC-MS/MS and the resulting peptide sequences were compared to existing databases. Understanding the roles and relationships of component enzymes from the T. reesei cellulase system acting on complex substrates is key to the development of efficient artificial cellulase systems for the conversion of lignocellulosic biomass to sugars. These studies suggest follow-on work comparing induced and noninduced T, reesei cells at the proteome level, which may elucidate substrate-specific gene regulation and response. C1 Natl Renewable Energy Lab, Biotechnol Ctr Fuels & Chem, Golden, CO 80401 USA. Univ Virginia, Sch Med, Biomol Res Facil, Charlottesville, VA 22908 USA. RP Himmel, ME (reprint author), Natl Renewable Energy Lab, Biotechnol Ctr Fuels & Chem, Golden, CO 80401 USA. NR 12 TC 73 Z9 76 U1 3 U2 19 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 99 EP 107 DI 10.1385/ABAB:91-93:1-9:99 PG 9 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100010 PM 11963908 ER PT J AU Rodriguez, M Klasson, KT Davison, BH AF Rodriguez, M Klasson, KT Davison, BH TI Enhancement of the conversion of toluene by Pseudomonas putida F-1 using organic cosolvents SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 22nd Symposium on Biotechnology for Fuels and Chemicals CY MAY 07-11, 2000 CL GATLINBURG, TENNESSEE SP US DOE, Off Fuels Dev, Oak Ridge Natl Lab, Off Ind Technologies, Agr & Chem Ind, Natl Renewable Energy Lab, Idaho Natl Engn & Envrionm Lab, Lockheed Martin Energy Res, Amer Chem Soc, Div Biochem Technol, Royal Nedalco BV, Raphael Katzen Associates, Tate & Lyle (AE Staley Mfg Co), Natl Resources Canada, Dupont Co, Iogen Corp, Corn Refiners Assoc Inc, Dow Chem Co, Argonne Natl Lab, NIST, Tembec Inc, Pure Energy Corp, TN Valley Authority, Public Power Inst, Cargill Inc DE Pseudomonas putida F-1; toluene; organic solvents; silicone oil ID GRAM-NEGATIVE BACTERIA; XENOBIOTIC-DEGRADING MICROORGANISMS; FATTY-ACIDS; SOLVENTS; BIOCATALYSIS; SYSTEM; BIODEGRADATION; REACTOR AB Pseudomonas putida F-1 (ATCC 700007) was used as a model organism in stirred tank reactors to study conversion enhancement of poorly soluble substrates by organic cosolvents. After a literature study, silicone oil was used as a solvent system to enhance the mass transfer rate. To study the benefits of the organic solvent addition, batch experiments were conducted in two side-hv-side fermentation vessels (experimental and control) at three different levels of silicone oil (10, 30, and 50%). Results showed that the presence of silicone oil resulted in a 100% increase in the toluene mass transfer compared to the control. Experiments in continuous stirred-tank reactors showed that improved conversion could be obtained at higher agitation rates. C1 Oak Ridge Natl Lab, Bioproc Res & Dev Ctr, Oak Ridge, TN 37831 USA. RP Klasson, KT (reprint author), Oak Ridge Natl Lab, Bioproc Res & Dev Ctr, POB 2008-6226, Oak Ridge, TN 37831 USA. RI Davison, Brian/D-7617-2013; OI Davison, Brian/0000-0002-7408-3609; Klasson, K. Thomas/0000-0003-3358-3081 NR 24 TC 3 Z9 3 U1 0 U2 3 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 195 EP 204 PG 10 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100019 PM 11963848 ER PT J AU Klasson, KT Davison, BH AF Klasson, KT Davison, BH TI Effect of temperature on biofiltration of nitric bride SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 22nd Symposium on Biotechnology for Fuels and Chemicals CY MAY 07-11, 2000 CL GATLINBURG, TENNESSEE SP US DOE, Off Fuels Dev, Oak Ridge Natl Lab, Off Ind Technologies, Agr & Chem Ind, Natl Renewable Energy Lab, Idaho Natl Engn & Envrionm Lab, Lockheed Martin Energy Res, Amer Chem Soc, Div Biochem Technol, Royal Nedalco BV, Raphael Katzen Associates, Tate & Lyle (AE Staley Mfg Co), Natl Resources Canada, Dupont Co, Iogen Corp, Corn Refiners Assoc Inc, Dow Chem Co, Argonne Natl Lab, NIST, Tembec Inc, Pure Energy Corp, TN Valley Authority, Public Power Inst, Cargill Inc DE nitric oxide; Paracoccus denitrificans; denitrification; trickle-bed biofilter; mass transfer ID GASEOUS WASTE STREAMS; MICROBIAL REMOVAL; NITROGEN-OXIDES; MASS-TRANSFER; GAS; KINETICS; ALKANES C1 Oak Ridge Natl Lab, Bioproc Res & Dev Ctr, Oak Ridge, TN 37831 USA. RP Klasson, KT (reprint author), Oak Ridge Natl Lab, Bioproc Res & Dev Ctr, POB 2008,MS-6226, Oak Ridge, TN 37831 USA. RI Davison, Brian/D-7617-2013; OI Davison, Brian/0000-0002-7408-3609; Klasson, K. Thomas/0000-0003-3358-3081 NR 15 TC 5 Z9 8 U1 0 U2 1 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 205 EP 211 DI 10.1385/ABAB:91-93:1-9:205 PG 7 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100020 PM 11963849 ER PT J AU Hanley, TR Thompson, DN AF Hanley, TR Thompson, DN TI Bioprocessing research SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Editorial Material C1 Univ Louisville, Louisville, KY 40292 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. RP Hanley, TR (reprint author), Univ Louisville, Louisville, KY 40292 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 235 EP 235 PG 1 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100023 PM 11963853 ER PT J AU Kim, KH Tucker, MP Keller, FA Aden, A Nguyen, QA AF Kim, KH Tucker, MP Keller, FA Aden, A Nguyen, QA TI Continuous countercurrent extraction of hemicellulose from pretreated wood residues SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 22nd Symposium on Biotechnology for Fuels and Chemicals CY MAY 07-11, 2000 CL GATLINBURG, TENNESSEE SP US DOE, Off Fuels Dev, Oak Ridge Natl Lab, Off Ind Technologies, Agr & Chem Ind, Natl Renewable Energy Lab, Idaho Natl Engn & Envrionm Lab, Lockheed Martin Energy Res, Amer Chem Soc, Div Biochem Technol, Royal Nedalco BV, Raphael Katzen Associates, Tate & Lyle (AE Staley Mfg Co), Natl Resources Canada, Dupont Co, Iogen Corp, Corn Refiners Assoc Inc, Dow Chem Co, Argonne Natl Lab, NIST, Tembec Inc, Pure Energy Corp, TN Valley Authority, Public Power Inst, Cargill Inc DE extraction; hemicellulose; softwood; pretreatment; acid hydrolysis AB Two-stage dilute acid pretreatment followed by enzymatic cellulose hydrolysis is an effective method for obtaining high sugar yields from wood residues such as softwood forest thinnings. In the first-stage hydrolysis step, most of the hemicellulose is solubilized using relatively mild conditions. The soluble hemicellulosic sugars are recovered from the hydrolysate slurry by washing with water. The washed solids are then subjected to more severe hydrolysis conditions to hydrolyze approx 50% of the cellulose to glucose. The remaining cellulose can further be hydrolyzed with cellulase enzyme. Our process simulation indicates that the amount of water used in the hemicellulose recovery step has a significant impact on the cost of ethanol production. It is important to keep water usage as low as possible while maintaining relatively high recovery of soluble sugars. To achieve this objective, a prototype pilot-scale continuous countercurrent screw extractor was evaluated for the recovery of hemicellulose from pretreated forest thinnings. Using the 274-cm (9-ft) long extractor, solubles recoveries of 98, 91, and 77% were obtained with liquid-to-insoluble solids (L/IS) ratios of 5.6, 3.4, and 2.1, respectively. An empirical equation was developed to predict the performance of the screw extractor. This equation predicts that soluble sugar recovery above 95% can be obtained with an L/IS ratio as low as 3.0. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Nguyen, QA (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Kim, Kyoung Heon/F-1059-2013 OI Kim, Kyoung Heon/0000-0003-4600-8668 NR 13 TC 26 Z9 27 U1 0 U2 9 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 253 EP 267 DI 10.1385/ABAB:91-93:1-9:253 PG 15 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100025 PM 11963855 ER PT J AU Kim, JS Lee, YY Torget, RW AF Kim, JS Lee, YY Torget, RW TI Cellulose hydrolysis under extremely low sulfuric acid and high-temperature conditions SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 22nd Symposium on Biotechnology for Fuels and Chemicals CY MAY 07-11, 2000 CL GATLINBURG, TENNESSEE SP US DOE, Off Fuels Dev, Oak Ridge Natl Lab, Off Ind Technologies, Agr & Chem Ind, Natl Renewable Energy Lab, Idaho Natl Engn & Envrionm Lab, Lockheed Martin Energy Res, Amer Chem Soc, Div Biochem Technol, Royal Nedalco BV, Raphael Katzen Associates, Tate & Lyle (AE Staley Mfg Co), Natl Resources Canada, Dupont Co, Iogen Corp, Corn Refiners Assoc Inc, Dow Chem Co, Argonne Natl Lab, NIST, Tembec Inc, Pure Energy Corp, TN Valley Authority, Public Power Inst, Cargill Inc DE yellow poplar; cellulose hydrolysis; bed-shrinking flow-through reactor; kinetics AB The kinetics of cellulose hydrolysis under extremely low acid (ELA) conditions (0.07 wt%) and at temperatures > 200 degreesC was investigated using batch reactors and bed-shrinking flow-through (BSFT) reactors. The maximum yield of glucose obtained from batch reactor experiments was about 60% for a-cellulose, which occurred at 205 and 220 degreesC. The maximum glucose yields from yellow poplar feedstocks were substantially lower, falling in the range of 26-50%. With yellow poplar feedstocks, a large amount of glucose was unaccounted for at the latter phase of the batch reactions. It appears that a substantial amount of released glucose condenses with nonglucosidic substances in liquid. The rate of glucan hydrolysis under ELA was relatively insensitive to temperature in batch experiments for all three substrates. This contradicts the traditional concept of cellulose hydrolysis and implies that additional factors influence the hydrolysis of glucan under ELA. In experiments using BSFT reactors, the glucose yields of 87.5, 90.3, and 90.8% were obtained for yellow poplar feedstocks at 205, 220, and 235 degreesC, respectively. The hydrolysis rate for glucan was about three times higher with the BSFT than with the batch reactors. The difference of observed kinetics and performance data between the BSFT and the batch reactors was far above that predicted by the reactor theory. C1 Auburn Univ, Dept Chem Engn, Auburn, AL 36849 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Lee, YY (reprint author), Auburn Univ, Dept Chem Engn, 230 Ross Hall, Auburn, AL 36849 USA. NR 11 TC 69 Z9 80 U1 0 U2 17 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 331 EP 340 DI 10.1385/ABAB:91-93:1-9:331 PG 10 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100031 PM 11963862 ER PT J AU Harris, RA Dale, BE AF Harris, RA Dale, BE TI Bioenergy and bioproducts - Forum on recent government initiatives SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Editorial Material C1 US DOE, Washington, DC 20585 USA. Michigan State Univ, E Lansing, MI 48824 USA. RP Harris, RA (reprint author), US DOE, Washington, DC 20585 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 481 EP 481 PG 1 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100044 ER PT J AU Thompson, DN Fox, SL Bala, GA AF Thompson, DN Fox, SL Bala, GA TI The effect of pretreatments on surfactin production from potato process effluent by Bacillus subtilis SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 22nd Symposium on Biotechnology for Fuels and Chemicals CY MAY 07-11, 2000 CL GATLINBURG, TENNESSEE SP US DOE, Off Fuels Dev, Oak Ridge Natl Lab, Off Ind Technologies, Agr & Chem Ind, Natl Renewable Energy Lab, Idaho Natl Engn & Envrionm Lab, Lockheed Martin Energy Res, Amer Chem Soc, Div Biochem Technol, Royal Nedalco BV, Raphael Katzen Associates, Tate & Lyle (AE Staley Mfg Co), Natl Resources Canada, Dupont Co, Iogen Corp, Corn Refiners Assoc Inc, Dow Chem Co, Argonne Natl Lab, NIST, Tembec Inc, Pure Energy Corp, TN Valley Authority, Public Power Inst, Cargill Inc DE Bacillus subtilis; biosurfactant; surfactin; alternate feedstock; enhanced oil recovery ID BIOSURFACTANTS AB Pretreatments of low-solids potato process effluent were tested for their potential to increase surfactin Yield. Pretreatments included heat, removal of starch particulates, and acid hydrolysis. Elimination of contaminating vegetative cells was necessary for surfactin production. After autoclaving, 0.40 g/L of surfactin was produced from the effluent in 72 h, vs 0.24 g/L in the purified potato starch control. However, surfactin yields per carbon consumed were 76% lower from process effluent. Removal of starch particulates had little effect on the culture. Acid hydrolysis decreased growth and surfactant production except 0.5 wt% acid, which increased the yield by 25% over untreated effluent. C1 Idaho Natl Engn & Environm Lab, Dept Biotechnol, Idaho Falls, ID 83415 USA. RP Thompson, DN (reprint author), Idaho Natl Engn & Environm Lab, Dept Biotechnol, POB 1625, Idaho Falls, ID 83415 USA. NR 22 TC 13 Z9 14 U1 0 U2 1 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 487 EP 501 DI 10.1385/ABAB:91-93:1-9:487 PG 15 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100046 PM 11963877 ER PT J AU Thompson, DN Hamilton, MA AF Thompson, DN Hamilton, MA TI Production of bacterial cellulose from alternate feedstocks SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 22nd Symposium on Biotechnology for Fuels and Chemicals CY MAY 07-11, 2000 CL GATLINBURG, TENNESSEE SP US DOE, Off Fuels Dev, Oak Ridge Natl Lab, Off Ind Technologies, Agr & Chem Ind, Natl Renewable Energy Lab, Idaho Natl Engn & Envrionm Lab, Lockheed Martin Energy Res, Amer Chem Soc, Div Biochem Technol, Royal Nedalco BV, Raphael Katzen Associates, Tate & Lyle (AE Staley Mfg Co), Natl Resources Canada, Dupont Co, Iogen Corp, Corn Refiners Assoc Inc, Dow Chem Co, Argonne Natl Lab, NIST, Tembec Inc, Pure Energy Corp, TN Valley Authority, Public Power Inst, Cargill Inc DE bacterial cellulose; Acetobacter xylinum; potato effluent; beet raffinate; whey permeate ID ACETOBACTER-XYLINUM KU-1; SYNTHETIC MEDIUM; BIOSYNTHESIS AB Production of bacterial cellulose by Acetobacter xylinum ATCC 10821 and 23770 in static cultures was tested from unamended food process effluents. Effluents included low-solids (LS) and high-solids (HS) potato effluents, cheese whey permeate (CW), or sugar beet raffinate (CSB). Strain 23770 produced 10% less cellulose from glucose than did strain 10821 and diverted more glucose to gluconate. Unamended HS, CW, and CSB were unsuitable for cellulose production by either strain, and LS was unsuitable for production by strain 10821. However, strain 23770 produced 17% more cellulose from LS than from glucose, indicating that unamended LS could serve as a feedstock for bacterial cellulose. C1 Idaho Natl Engn & Environm Lab, Dept Biotechnol, Idaho Falls, ID 83415 USA. RP Thompson, DN (reprint author), Idaho Natl Engn & Environm Lab, Dept Biotechnol, POB 1625, Idaho Falls, ID 83415 USA. NR 27 TC 20 Z9 22 U1 2 U2 8 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 503 EP 513 DI 10.1385/ABAB:91-93:1-9:503 PG 11 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100047 PM 11963879 ER PT J AU Schell, DJ Farmer, J Hamilton, J Lyons, B McMillan, JD Saez, JC Tholudar, A AF Schell, DJ Farmer, J Hamilton, J Lyons, B McMillan, JD Saez, JC Tholudar, A TI Influence of operating conditions and vessel size on oxygen transfer during cellulase production SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 22nd Symposium on Biotechnology for Fuels and Chemicals CY MAY 07-11, 2000 CL GATLINBURG, TENNESSEE SP US DOE, Off Fuels Dev, Oak Ridge Natl Lab, Off Ind Technologies, Agr & Chem Ind, Natl Renewable Energy Lab, Idaho Natl Engn & Envrionm Lab, Lockheed Martin Energy Res, Amer Chem Soc, Div Biochem Technol, Royal Nedalco BV, Raphael Katzen Associates, Tate & Lyle (AE Staley Mfg Co), Natl Resources Canada, Dupont Co, Iogen Corp, Corn Refiners Assoc Inc, Dow Chem Co, Argonne Natl Lab, NIST, Tembec Inc, Pure Energy Corp, TN Valley Authority, Public Power Inst, Cargill Inc DE oxygen transfer; mass transfer coefficient; cellulase; cellulose; ethanol ID TRICHODERMA-REESEI; MASS-TRANSFER; XANTHAN FERMENTATIONS; IMPELLER TYPE; AGITATION; COMPONENTS AB The production of low-cost cellulase enzyme is a key step in the development of an enzymatic-based process for conversion of lignocellulosic biomass to ethanol. Although abundant information is available on cellulase production, little of this work has examined oxygen transfer. We investigated oxygen transfer during the growth of Trichoderma reesei, a cellulase-producing microorganism, on soluble and insoluble substrates in vessel sizes from 7 to 9000 L. Oxygen uptake rates and volumetric mass transfer coefficients (k(L)a) were determined using mass spectroscopy to measure off gas composition. Experimentally measured k(L)a values were found to compare favorably with a k(L)a correlation available in the literature for a non-Newtonian fermentation broth during the period of heavy cell growth. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Schell, DJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 25 TC 14 Z9 14 U1 1 U2 8 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 2001 VL 91-3 BP 627 EP 642 DI 10.1385/ABAB:91-93:1-9:627 PG 16 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 430GX UT WOS:000168567100058 PM 11963891 ER PT J AU Sasian, JM Lerner, SA Lin, TY Laughlin, L AF Sasian, JM Lerner, SA Lin, TY Laughlin, L TI Ray and van Cittert-Zernike characterization of spatial coherence SO APPLIED OPTICS LA English DT Article ID PROJECTION LITHOGRAPHY AB We discuss a ray and a van Cittert-Zernike characterization of spatial coherence in condensers for projection systems. We present a rule of thumb with which to estimate the modulus of the coherence function at a given point of the illuminated object and a ray-tracing methodology with which to determine this modulus. For uniform illumination of the pupil we relate the modulus of the coherence function and the pupil-filling factor. We suggest that the rms of the angular ray spread at a given object point is an appropriate metric with which to characterize local coherence properties. (C) 2001 Optical Society of America C1 Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Sasian, JM (reprint author), Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. EM Jose.sasian@optics.arizona.edu NR 9 TC 1 Z9 1 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD MAR 1 PY 2001 VL 40 IS 7 BP 1037 EP 1043 DI 10.1364/AO.40.001037 PG 7 WC Optics SC Optics GA 404QV UT WOS:000167112900004 PM 18357087 ER PT J AU Shultis, JK Khan, F Letellier, B Faw, RE AF Shultis, JK Khan, F Letellier, B Faw, RE TI Determining soil contamination profiles from intensities of capture-gamma rays using above-surface neutron sources (vol 50, pg 415, 1999) SO APPLIED RADIATION AND ISOTOPES LA English DT Correction AB Four methods are presented to estimate contaminant concentration profiles in soil from the intensities of neutron-induced capture-gamma photon intensities measured at the soil surface. In particular, the method of linear regularization with and without an iterative positivity constraint, the Backus-Gilbert method, and the maximum entropy method are applied to the soil contamination problem. Example results obtained with the four methods are given for photon intensities calculated for idealized test contaminant profiles in soil irradiated by neutron sources above the surface. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Kansas State Univ, Dept Mech & Nucl Engn, Manhattan, KS 66506 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Shultis, JK (reprint author), Kansas State Univ, Dept Mech & Nucl Engn, Manhattan, KS 66506 USA. NR 24 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD MAR PY 2001 VL 54 IS 3 BP 563 EP + PG 20 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 396QU UT WOS:000166648700027 ER PT J AU Eland, KL Stratis, DN Gold, DM Goode, SR Angel, SM AF Eland, KL Stratis, DN Gold, DM Goode, SR Angel, SM TI Energy dependence of emission intensity and temperature in a LIBS plasma using femtosecond excitation SO APPLIED SPECTROSCOPY LA English DT Article DE LIBS; LIPS; short-pulse LIBS; laser-induced breakdown spectroscopy; laser ablation; laser-induced plasmas; femtosecond LIBS; ultrafast laser ID LASER-INDUCED-BREAKDOWN; SPECTROSCOPY; ABLATION; PROBE; MICROSCOPY; METALS; GLASS; FS AB In this paper, we investigate the effect of laser energy on laser-induced breakdown emission intensity and average temperature in a short-pulse plasma generated by using 140 fs laser excitation. Both line emission and continuum background intensity and plasma temperature decrease very rapidly after excitation compared to the more conventional nanosecond pulse excitation. Both emission intensity and plasma temperature increase with increasing laser energy. However, the intensity increase appears to he mostly related to the amount of material ablated. Also, nongated laser-induced breakdown spectroscopy (LIBS) is demonstrated using a high-pulse (1 kHz) pulse repetition rate. C1 Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94550 USA. RP Angel, SM (reprint author), Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. OI Goode, Scott/0000-0001-5445-5682; Angel, Stanley/0000-0002-0328-0568 NR 33 TC 75 Z9 77 U1 4 U2 14 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD MAR PY 2001 VL 55 IS 3 BP 286 EP 291 DI 10.1366/0003702011951902 PG 6 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 417ZF UT WOS:000167864800008 ER PT J AU Lee, TC Malone, B Longobardi, L Balestrieri, ML AF Lee, TC Malone, B Longobardi, L Balestrieri, ML TI Differential regulation of three catalytic activities of platelet-activating factor (PAF)-dependent transacetylase SO ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS LA English DT Article DE platelet-activating factor; transacetylase; acetylhydrolase; C-2-ceramide; analogs of PAF ID LECITHIN-CHOLESTEROL ACYLTRANSFERASE; COA-INDEPENDENT TRANSACETYLASE; ENDOTHELIAL-CELLS; ACYL ANALOGS; HL-60 CELLS; BIOSYNTHESIS; HYDROLYSIS; PAF; ACETYLHYDROLASES AB We have previously established that PAF-dependent transacetylase (TA) purified to apparent homogeneity from rat kidney membranes and cytosol contains three separate catalytic activities, namely PAF lysophospholipid transacetylase (TA(1)), PAF sphingosine transacetylase (TA(s)), and PAF acetylhydrolase (AH), In the present investigation, we studied the biochemical factors and mechanism(s) that differentially regulate these three TA activities of the purified enzymes. We found that only the TA(s) activity of the TA purified from the membranes was stimulated by phosphatidylserine (PS) with optimal concentration of activation occurring at 25 muM, Other acidic phospholipids, such as phosphatidylinositol (PI) and phosphatidylinositol I-phosphate (PIP), are partially effective, while diacylglycerol and free fatty acids had no effect on the TA(s) activity. PS exerted its effect on the TA(s) activity through the increases of both K-m and V-max. In addition, N-ethylmalimide (NEM) and dithiobis-(2-nitro-5-thiobenzoic acid) (DTNB) strongly inhibited the TA(L) activity and partially decreased the TA(L) and AH activities of the purified membrane enzyme in a dose-dependent manner. The addition of PS, but not by its substrate, sphingosine, could prevented the inhibition by NEM on the basal level of TA(s). On the other hand, the inhibition of TAL by NEM and DTNB were partially protected by the substrate, lysoplasmalogens, Furthermore, PAF fully protects the inhibition of AH, partially protects the inhibition of TA(L), and does not protect the inhibition of TA(s) by NEM, These results suggested that the three individual catalytic activities of TA have different dependencies on the thiol-containing residue(s) of the enzyme, i.e., cysteine. Furthermore, the nonresponsiveness of the purified cytosolic TA(s) to PS activation is consistent with our previous notions that membrane and cytosolic TA are posttranslationally distinct. (C) 2001 Academic Press. C1 Oak Ridge Associated Univ, Basic & Appl Res Unit, Oak Ridge, TN 37831 USA. Univ Naples 2, Dept Biochem & Biophys F Cedrangolo, I-80138 Naples, Italy. RP Lee, TC (reprint author), Oak Ridge Associated Univ, Basic & Appl Res Unit, Oak Ridge, TN 37831 USA. FU NHLBI NIH HHS [HL-52492] NR 16 TC 5 Z9 6 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-9861 J9 ARCH BIOCHEM BIOPHYS JI Arch. Biochem. Biophys. PD MAR 1 PY 2001 VL 387 IS 1 BP 41 EP 46 DI 10.1006/abbi.2000.2226 PG 6 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 409XR UT WOS:000167411400006 PM 11368182 ER PT J AU Reed, BR Eberling, JL Mungas, D Weiner, M Jagust, WJ AF Reed, BR Eberling, JL Mungas, D Weiner, M Jagust, WJ TI Frontal lobe hypometabolism predicts cognitive decline in patients with lacunar infarcts SO ARCHIVES OF NEUROLOGY LA English DT Article ID CEREBRAL BLOOD-FLOW; POSITRON EMISSION TOMOGRAPHY; ALZHEIMERS-DISEASE; VASCULAR DEMENTIA; COMPUTED-TOMOGRAPHY; GLUCOSE-METABOLISM; SENILE DEMENTIA; STROKE; PERFUSION; RISK AB Background: A proportion of patients with subcortical lacunes will suffer progressive cognitive dysfunction, but the basis for this decline is controversial and little is known about predicting cognitive decline in these patients. Studies of Alzheimer disease have shown that imaging measures of temporal and parietal metabolism and blood flow predict disease course. Objective: To determine whether regional cerebral glucose metabolism predicts cognitive decline by testing 2 opposing hypotheses: (1) temporoparietal activity predicts decline (based on the idea that concomitant Alzheimer disease causes decline) vs (2) frontal hypometabolism predicts decline (based on evidence that subcortical frontal circuits are especially vulnerable to small vessel ischemia). Design: Prospective cohort study. Setting: University outpatient dementia center. Patients: A convenience sample of 26 patients with radiologically defined lacunes and baseline cognitive function ranging from normal to moderately demented. Main Outcome Measures: Regional cerebral metabolism was quantitated in the form of atrophy-corrected positron emission tomographic activity ratios in cortical regions that were defined a priori. Patients were followed up at a mean of 1.8 years, and the dependent variable was rate of change in the Mini-Mental State Examination score. Results: Bilateral and right hemisphere dorsolateral frontal metabolism significantly predicted cognitive decline, with right dorsolateral frontal metabolism explaining 19% of the variance. No other positron emission tomographic region was a significant predictor, nor were demographic variables or baseline Mini-Mental State Examination scores significant predictors. Conclusion: Cognitive decline in patients with lacunes may result in part from progressive vascular compromise in subcortical frontal circuits. C1 Univ Calif Davis, Dept Neurol, Davis, CA 95616 USA. No Calif Hlth Care Syst, Dept Vet Affairs, Martinez, CA USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Univ Calif San Francisco, Dept Med, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Radiol, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Psychiat, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Neurol, San Francisco, CA 94143 USA. Dept Vet Affairs Med Ctr, San Francisco, CA USA. RP Reed, BR (reprint author), UCD, Alzheimers Dis Ctr, 150 Muir Rd 127A, Martinez, CA 94553 USA. RI Mungas, Dan/E-6810-2011 FU NIA NIH HHS [AG12435, AG10129] NR 49 TC 40 Z9 40 U1 2 U2 2 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0003-9942 J9 ARCH NEUROL-CHICAGO JI Arch. Neurol. PD MAR PY 2001 VL 58 IS 3 BP 493 EP 497 DI 10.1001/archneur.58.3.493 PG 5 WC Clinical Neurology SC Neurosciences & Neurology GA 410LR UT WOS:000167441900021 PM 11255455 ER PT J AU Schneider, DP Fan, XH Strauss, MA Gunn, JE Richards, GT Hill, GJ MacQueen, JP Ramsey, LW Adams, MT Booth, JA Hill, GM Knapp, GR Lupton, RH Saxe, DH Shetrone, M Tufts, JR Vanden Berk, DE Wolf, MJ York, DG Anderson, JE Anderson, SF Bahcall, NA Brinkmann, J Brunner, R Csabai, I Fukugita, M Hennessy, GS Ivezic, Z Lamb, DQ Munn, JA Thakar, AR AF Schneider, DP Fan, XH Strauss, MA Gunn, JE Richards, GT Hill, GJ MacQueen, JP Ramsey, LW Adams, MT Booth, JA Hill, GM Knapp, GR Lupton, RH Saxe, DH Shetrone, M Tufts, JR Vanden Berk, DE Wolf, MJ York, DG Anderson, JE Anderson, SF Bahcall, NA Brinkmann, J Brunner, R Csabai, I Fukugita, M Hennessy, GS Ivezic, Z Lamb, DQ Munn, JA Thakar, AR TI High-redshift quasars found in Sloan Digital Sky Survey commissioning data. V. Hobby-Eberly telescope observations SO ASTRONOMICAL JOURNAL LA English DT Article DE early universe; quasars : general ID LOW-RESOLUTION SPECTROGRAPH; FALL EQUATORIAL STRIPE; LUMINOSITY FUNCTION; RADIO PROPERTIES; SAMPLE; SPECTROPHOTOMETRY; PERFORMANCE; EVOLUTION; DISCOVERY; CONTINUUM AB We report the discovery of 27 quasars with redshifts between 3.58 and 4.49. The objects were identified as high-redshift candidates based on their colors in Sloan Digital Sky Survey commissioning data. The redshifts were confirmed with low-resolution spectra obtained at the Hobby-Eberly Telescope. The quasars' i* magnitudes range from 18.55 to 20.97. Nearly 60% of the quasar candidates observed are confirmed spectroscopically as quasars. Two of the objects are broad absorption line quasars, and several other quasars appear to have narrow associated absorption features. C1 Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Inst Adv Study, Princeton, NJ 08540 USA. Univ Texas, Dept Astron, McDonald Observ, Austin, TX 78712 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Apache Point Observ, Sunspot, NM 88349 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Eotvos Lorand Univ, Dept Phys Complex Syst, H-1117 Budapest, Hungary. Univ Tokyo, Inst Cosm Ray Res, Tokyo 1888502, Japan. USN Observ, Washington, DC 20392 USA. USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. RP Schneider, DP (reprint author), Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. RI Csabai, Istvan/F-2455-2012; OI Csabai, Istvan/0000-0001-9232-9898 NR 41 TC 42 Z9 42 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAR PY 2001 VL 121 IS 3 BP 1232 EP 1240 DI 10.1086/319422 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 412YL UT WOS:000167582800002 ER PT J AU De Breuck, C van Breugel, W Rottgering, H Stern, D Miley, G de Vries, W Stanford, SA Kurk, J Overzier, R AF De Breuck, C van Breugel, W Rottgering, H Stern, D Miley, G de Vries, W Stanford, SA Kurk, J Overzier, R TI Spectroscopy of ultra-steep-spectrum radio sources SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : distances and redshifts; pulsars : general; radio continuum; surveys ID COMPLETE QUASAR SAMPLE; HIGH-REDSHIFT; SKY SURVEY; EMISSION-LINES; OPTICAL SPECTROSCOPY; GALAXIES; EVOLUTION; CATALOG; DISCOVERY; OBJECTS AB We present optical spectroscopy of 62 objects selected from several samples of ultra-steep-spectrum radio sources. Forty-six of these are from our primary catalog, consisting of 669 sources with radio spectral indices alpha < -1.30 (S() infinity nu (alpha)); this first spectroscopic subsample was selected on the basis of their faint optical and near-IR identifications. Most are identified as narrow-lined radio galaxies with redshifts ranging from z = 0.25 to z = 5.19. Ten objects are at z >3, nearly doubling the number of such sources known to date. Four of the USS radio sources are identified with quasars, of which at least three have very red spectral energy distributions. The source TN J0936-2242 is identified with an extremely red object (ERO, R-K > 5); both it and a close companion are at z = 1.479. The spectrum of the ERO closely resembles that of previously discovered radio galaxies at z similar to 1.5. Five sources show continuum emission, but fail to show any clear emission or absorption features, despite integrations of similar to1 hr with the Keck telescope. We suggest that these objects could be (1) radio galaxies with faint emission lines in the "redshift desert" at 1.5 less than or similar to z less than or similar to 2.3, (2) radio galaxies with an obscured active galactic nucleus, which are dominated by a stellar continuum observed with an insufficient signal-to-noise ratio, or (3) pulsars. Three radio sources identified with faint objects in the K-band images remain undetected in 50-90 minute spectroscopic integrations with the Keck telescope, and are possible z > 7 candidates. C1 Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP De Breuck, C (reprint author), Inst Astrophys Paris, 98 Bis Blvd Arago, F-75014 Paris, France. NR 88 TC 58 Z9 59 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAR PY 2001 VL 121 IS 3 BP 1241 EP 1265 DI 10.1086/319392 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 412YL UT WOS:000167582800003 ER PT J AU Beiersdorfer, P Lisse, CM Olson, RE Brown, GV Chen, H AF Beiersdorfer, P Lisse, CM Olson, RE Brown, GV Chen, H TI X-ray velocimetry of solar wind ion impact on comets SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic data; atomic processes; comets : general; X-rays : general ID EXTREME-ULTRAVIOLET EMISSION; ELECTRON-CAPTURE COLLISIONS; HIGHLY-CHARGED IONS; HALE-BOPP; HYAKUTAKE; EXCHANGE; TRAP AB Laboratory measurements of the interaction of low-energy, bare, and hydrogen-like ions with neutral gases are presented. The measurements demonstrate that charge-exchange-induced cometary K-shell X-ray spectra represent rich spectral diagnostics for determining the speed of the solar wind and the collision dynamics within the coma. We show that the K-shell spectrum observed from low-energy ion-neutral collisions (less than or equal to 50 km s(-1)) has a distinct high-energy component that is suppressed in high-energy collisions (greater than or equal to 800 km s(-1)). As a result, the hardness ratio of the K-shell spectrum increases by as much as a factor of 4 as the ions decelerate in the coma. The change in spectral shape can be observed even with low-resolution energy dispersive solid-state detectors, opening the possibility of spatial imaging of the solar wind heavy-ion velocity profile in the coma. Our results clearly show that energy-dependent data are needed to fully describe charge-exchange-induced Xray production in the heliosphere. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Phys, Livermore, CA 94551 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Missouri, Dept Phys, Rolla, MO 65401 USA. RP Beiersdorfer, P (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Phys, Livermore, CA 94551 USA. RI Lisse, Carey/B-7772-2016 OI Lisse, Carey/0000-0002-9548-1526 NR 27 TC 65 Z9 65 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2001 VL 549 IS 1 BP L147 EP L150 DI 10.1086/319143 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 406HK UT WOS:000167208700034 ER PT J AU Harris, HC Hansen, BMS Liebert, J Vanden Berk, DE Anderson, SF Knapp, GR Fan, XH Margon, B Munn, JA Nichol, RC Pier, JR Schneider, DP Smith, JA Winget, DE York, DG Anderson, JE Brinkmann, J Burles, S Chen, B Connolly, AJ Csabai, I Frieman, JA Gunn, JE Hennessy, GS Hindsley, RB Ivezic, Z Kent, S Lamb, DQ Lupton, RH Newberg, HJ Schlegel, DJ Smee, S Strauss, MA Thakar, AR Uomoto, A Yanny, B AF Harris, HC Hansen, BMS Liebert, J Vanden Berk, DE Anderson, SF Knapp, GR Fan, XH Margon, B Munn, JA Nichol, RC Pier, JR Schneider, DP Smith, JA Winget, DE York, DG Anderson, JE Brinkmann, J Burles, S Chen, B Connolly, AJ Csabai, I Frieman, JA Gunn, JE Hennessy, GS Hindsley, RB Ivezic, Z Kent, S Lamb, DQ Lupton, RH Newberg, HJ Schlegel, DJ Smee, S Strauss, MA Thakar, AR Uomoto, A Yanny, B TI A new very cool white dwarf discovered by the Sloan Digital Sky Survey SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : atmospheres; stars : individual (SDSSp J133739.40+000142.8); white dwarfs ID MODEL ATMOSPHERES; GALACTIC DISK; HYDROGEN-RICH; DARK HALO; OBJECTS; LUMINOSITY; EVOLUTION; SYSTEM; STARS; OLD AB Early data taken during commissioning of the Sloan Digital Sky Survey (SDSS) have resulted in the discovery of a very cool white dwarf. It appears to have stronger collision-induced absorption from molecular hydrogen than any other known white dwarf, suggesting it has a cooler temperature than any other. While its distance is presently unknown, it has a surprisingly small proper motion, making it unlikely to be a halo star. An analysis of white dwarf cooling times suggests that this object may be a low-mass star with a helium core. The SDSS imaging and spectroscopy also recovered LHS 3250, the coolest previously known white dwarf, indicating that the SDSS will be an effective tool for identifying these extreme objects. C1 USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Inst Adv Study, Princeton, NJ 08540 USA. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15232 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Apache Point Observ, Sunspot, NM 88349 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Eotvos Lorand Univ, Dept Phy Complex Syst, H-1518 Budapest, Hungary. USN Observ, Washington, DC 20392 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Rensselaer Polytech Inst, Dept Phys, Troy, NY 12180 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Harris, HC (reprint author), USN Observ, Flagstaff Stn, POB 1149, Flagstaff, AZ 86002 USA. RI Margon, Bruce/B-5913-2012; Csabai, Istvan/F-2455-2012; OI Csabai, Istvan/0000-0001-9232-9898; Smith, J. Allyn/0000-0002-6261-4601 NR 42 TC 49 Z9 49 U1 1 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2001 VL 549 IS 1 BP L109 EP L113 DI 10.1086/319146 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 406HK UT WOS:000167208700026 ER PT J AU Swift, JJ Welch, WJ Frye, BL AF Swift, JJ Welch, WJ Frye, BL TI Spatially resolved millimeter spectroscopy of the gravitational lens PKS 1830-211 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : ISM; gravitational lensing; ISM : molecules; quasars : individual (PKS 1830-211) ID REDSHIFTED MOLECULAR ABSORPTION; EINSTEIN RING; RADIO-SOURCE; PKS1830-211; PKS-1830-211; IMAGES; SYSTEM AB This paper presents data from the BIMA interferometer showing spatially resolved absorption spectra of the gravitationally lensed quasar PKS 183-211. High-resolution (1.2 km s(-1)) spectra were taken in two spectral windows centered on the redshifted frequencies of the HCO+(2 <-- 1) and HCN(2 <-- 1) molecular transitions. There is no molecular absorption in the northeast image, but the southwest image reveals optically thick absorbing gas at these transition frequencies. Further analyses conclude that the spectra are consistent with completely saturated absorption in the southwest image, and the line profiles suggest that the absorbing medium is complex, perhaps containing multiple components and small-scale structure. The absorption occurs along a pencil beam through the lensing galaxy which is thought to be a late-type spiral oriented almost face-on. However, the spectra show absorption spanning more than 60 km s(-1), which is difficult to explain for this scenario. C1 Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Phys, Berkeley, CA 94720 USA. RP Swift, JJ (reprint author), Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA. NR 16 TC 10 Z9 10 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2001 VL 549 IS 1 BP L29 EP L32 DI 10.1086/319144 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 406HK UT WOS:000167208700007 ER PT J AU Nahar, SN Pradhan, AK Zhang, HL AF Nahar, SN Pradhan, AK Zhang, HL TI Electron-ion recombination rate coefficients and photoionization cross sections for astrophysically abundant elements. v. relativistic calculations for Fe XXIV and Fe XXV for X-ray modeling SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE atomic data; atomic processes; line : formation; X-ray : general ID DIELECTRONIC SATELLITE SPECTRA; HELIUM-LIKE IONS; ATOMIC DATA; IRON PROJECT; LINE RATIOS; TEMPERATURE; IONIZATION; RESONANCES; DENSITY; PLASMAS AB Photoionization and recombination cross sections and rate coefficients are calculated for Li-like Fe XXIV and He-like Fe XXV using the Breit-Pauli R-matrix (BPRM) method. A complete set of total and level-specific parameters is obtained to enable X-ray photoionization and spectral modeling. The ab initio calculations for the unified (e + ion) recombination rate coefficients include both the nonresonant and the resonant recombination (radiative and dielectronic recombination, RR and DR, respectively) for (e + Fe XXV) --> Fe XXIV and (e + Fe XXVI) --> Fe XXV. The level-specific rates are computed for all fine-structure levels up to n = 10, enabling accurate computation of recombination-cascade matrices and effective rates for the X-ray lines. The total recombination rate coefficients for both Fe XXIV and Fe XXV differ considerably from the sum of RR and DR rates currently used to compute ionization fractions in astrophysical models. As the photoionization/recombination calculations are carried out using an identical eigenfunction expansion, the cross sections for both processes are theoretically self-consistent; the overall uncertainty is estimated to be about 10%-20%. All data for Fe XXIV and Fe XXV (and also for H-like Fe XXVI, included for completeness) are available electronically. C1 Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. RP Nahar, SN (reprint author), Ohio State Univ, Dept Astron, 174 W 18Th Ave, Columbus, OH 43210 USA. NR 34 TC 24 Z9 24 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD MAR PY 2001 VL 133 IS 1 BP 255 EP 267 DI 10.1086/319187 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 406YG UT WOS:000167243300009 ER PT J AU Bielicki, JK Knoff, LJ Tribble, DL Forte, TM AF Bielicki, JK Knoff, LJ Tribble, DL Forte, TM TI Relative sensitivities of plasma lecithin : cholesterol acyltransferase, platelet-activating factor acetylhydrolase, and paraoxonase to in vitro gas-phase cigarette smoke exposure SO ATHEROSCLEROSIS LA English DT Article DE atherogenic properties; cigarette smoke; LCAT; PAF-AH; PON ID LOW-DENSITY-LIPOPROTEIN; ENZYMES FREE THIOLS; OXIDATIVE MODIFICATION; ASCORBIC-ACID; METABOLISM; INHIBITION; EXTRACT; LDL AB In order to identify potential atherogenic properties of gas-phase cigarette smoke, we utilized an in vitro exposure model to determine whether the activities of several putative anti-atherogenic enzymes associated with plasma lipoproteins were compromised. Exposure of heparinized human plasma to gas-phase cigarette smoke produced a dose-dependent reduction in the activity of platelet-activating factor acetylhydrolase (PAF-AH). Reductions of nearly 50% in PAF-AH activity were observed following exposure to gas-phase smoke from four cigarettes over an 8-h period. During this time of exposure, lecithin:cholesterol acyltransferase (LCAT) was rendered almost completely inactive (> 80%). In contrast, paraoxonase was totally unaffected by cigarette smoke. Supplementation of plasma with 1 mM reduced glutathione was found to protect both PAF-AH and LCAT from cigarette smoke, suggesting that cysteine modifications may have contributed to the inhibition of these two enzymes. To evaluate this possibility, we blocked the free cysteine residues of these enzymes with the reversible thiol-modifying reagent dithiobisnitrobenzoic acid (DTNB). Reversal of the DTNB-cysteine adducts following cigarette smoke exposures revealed that LCAT, but not PAF-AH, was protected. Moreover, high doses (1.0-10 mM) of acrolein and 4-hydroxynonenal, reactive aldehydic species associated with cigarette smoke, completely inhibited plasma LCAT activity, whereas PAF-AH was resistant to such exposures. Taken together, these results indicate a divergence regarding the underlying mechanism of PAF-AH and LCAT inhibition upon exposure to gas-phase cigarette smoke. While LCAT was sensitive to exposure to volatile aldehydic products involving, in part, cysteine and/or active site modifications, the enzyme PAF-AH exhibited an apparent resistance. The latter suggests that the active site of PAF-AH is in a microenvironment that lacks free cysteine residues and/or is shielded from volatile aldehydic combustion products. Based on these results, we propose that cigarette smoke may contribute to atherogenesis by inhibiting the activities of plasma PAF-AH and LCAT, but the nature of this inhibition differs for the enzymes. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Donner Lab, Berkeley, CA 94720 USA. RP Bielicki, JK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Donner Lab, MS 1-213, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [HL59483-01A2, HL18574] NR 32 TC 9 Z9 11 U1 0 U2 0 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0021-9150 J9 ATHEROSCLEROSIS JI Atherosclerosis PD MAR PY 2001 VL 155 IS 1 BP 71 EP 78 DI 10.1016/S0021-9150(00)00539-6 PG 8 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 407RQ UT WOS:000167284900009 PM 11223428 ER PT J AU Safronova, UI Johnson, WR Albritton, JR AF Safronova, UI Johnson, WR Albritton, JR TI Auger rates for Ni-, Cu-, and Zn-like ions SO ATOMIC DATA AND NUCLEAR DATA TABLES LA English DT Article ID MANY-BODY CALCULATIONS; EXCITED 3LNL' STATES; L-SHELL AUGER; THEORETICAL-ANALYSIS; FLUORESCENCE YIELDS; N=2 STATES; TRANSITIONS; PLASMAS; SPECTRA AB Relativistic calculations of nonradiative transition rates to K-, L-, and M-shell vacancy states in Ni-, Cu-, and Zn-like ions with Z = 32, 36, 42, 47, 56, 60, 66, 74, 83, and 92 are performed. Auger and Coster-Kronig transition probabilities are calculated using both Dirac-Hartree-Fock and model-potential wave functions. Tabulated data are presented for K- and L-shell Auger rates in Ni-, Cu-, and Zn-like ions, for M-shell Anger rates in Zn-like ions, and for L- and M-shell Coster-Kronig rates in Cu-like ions. Results obtained by averaging over angular momentum substates are also presented and semiempirical formulas are given for the average rates. (C) 2001 Academic Press. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Safronova, UI (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. NR 20 TC 5 Z9 5 U1 1 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0092-640X J9 ATOM DATA NUCL DATA JI Atom. Data Nucl. Data Tables PD MAR PY 2001 VL 77 IS 2 BP 215 EP 275 DI 10.1006/adnd.2000.0855 PG 61 WC Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Physics GA 427YB UT WOS:000168433400002 ER PT J AU Lavrik, NV Tipple, CA Sepaniak, MJ Datskos, PG AF Lavrik, Nickolay V. Tipple, Christopher A. Sepaniak, Michael J. Datskos, Panos G. TI Gold Nano-Structures for Transduction of Biomolecular Interactions into Micrometer Scale Movements SO BIOMEDICAL MICRODEVICES LA English DT Article DE actuator; BioMEMS; cantilever; colloidal gold; immunosensor; nanoparticles AB Microfabricated cantilevers, similar to those commonly used in scanning probe microscopies, have recently become increasingly popular as transducers in chemical and biological sensors. Surface stress changes that accompany intermolecular interactions on the cantilever surfaces offer an attractive means to develop new generations of microfabricated sensors and actuators that respond directly to chemical stimuli. In the present study, we demonstrate that interfacial molecular recognition events can be converted into mechanical responses much more efficiently when quasi 3-dimensional interfaces with nano-size features are used. Some of the particularly useful approaches to creating such interfaces are surface immobilization of gold nano-spheres and dealloying of co-evaporated Au:Ag films. Preliminary evaluation of these nanostructured surfaces was performed by measuring mechanical stresses generated by receptor modified nano-structures and smooth gold surfaces in response to gas-phase hydrocarbon compounds. The most efficient chemi-mechanical transduction was achieved when the cantilevers were modified with 50 to 75 nm thick dealloyed gold nanostrutures. Cantilevers of this type were selected for liquid phase experiments. These cantilevers were found to undergo several micron deflections upon adsorption of protein A and biotin-labeled albumin on nanostructured gold surfaces. Additional micrometer scale movements of the cantilevers were observed upon interaction of the surface bound bioreceptors with, respectively, immunoglobulin G and avidin from the aqueous phase. C1 [Lavrik, Nickolay V.; Tipple, Christopher A.; Sepaniak, Michael J.] Univ Tennessee, Dept Chem, Knoxville, TN 37919 USA. [Datskos, Panos G.] Oak Ridge Natl Lab, Engn Technol Div, Oak Ridge, TN 37831 USA. RP Lavrik, NV (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37919 USA. RI Lavrik, Nickolay/B-5268-2011 OI Lavrik, Nickolay/0000-0002-9543-5634 FU U.S. Department of Energy, Environmental Management Program [DOE DE-FG07-98ER62718]; DOE Basic Energy Sciences [DE-FG02-96ER14609]; National Science Foundation [CHE-9320461] FX This work was supported by the U.S. Department of Energy, Environmental Management Program under grant DOE DE-FG07-98ER62718, DOE Basic Energy Sciences under grant DE-FG02-96ER14609 and by National Science Foundation under Grant CHE-9320461. The authors gratefully acknowledge James Corbeil and Gerald De Vault for their help with AFM and SEM imaging and Dr. Thomas Green for synthesizing the HM-beta-CD. NR 37 TC 71 Z9 73 U1 1 U2 8 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1387-2176 EI 1572-8781 J9 BIOMED MICRODEVICES JI Biomed. Microdevices PD MAR PY 2001 VL 3 IS 1 BP 35 EP 44 DI 10.1023/A:1011473203133 PG 10 WC Engineering, Biomedical; Nanoscience & Nanotechnology SC Engineering; Science & Technology - Other Topics GA V33KU UT WOS:000209018500005 ER PT J AU Woenckhaus, J Kohling, R Thiyagarajan, P Littrell, KC Seifert, S Royer, CA Winter, R AF Woenckhaus, J Kohling, R Thiyagarajan, P Littrell, KC Seifert, S Royer, CA Winter, R TI Pressure-jump small-angle x-ray scattering detected kinetics of staphylococcal nuclease folding SO BIOPHYSICAL JOURNAL LA English DT Article ID INDIRECT FOURIER TRANSFORMATION; STRUCTURAL-CHARACTERIZATION; PROTEIN; DENATURATION; MUTANTS; STABILITY; STATE; PERSPECTIVE; MUTATIONS AB The kinetics of chain disruption and collapse of staphylococcal nuclease after positive or negative pressure jumps was monitored by real-time small-angle x-ray scattering under pressure. We used this method to probe the overall conformation of the protein by measuring its radius of gyration and pair-distance-distribution function p(r) which are sensitive to the spatial extent and shape of the particle. At all pressures and temperatures tested, the relaxation profiles were well described by a single exponential function. No fast collapse was observed, indicating that the rate limiting step for chain collapse is the same as that for secondary and tertiary structure formation. Whereas refolding at low pressures occurred in a few seconds, at high pressures the relaxation was quite slow, similar to1 h, due to a large positive activation volume for the rate-limiting step for chain collapse. A large increase in the system volume upon folding implies significant dehydration of the transition state and a high degree of similarity in terms of the packing density between the native and transition states in this system. This study of the time-dependence of the tertiary structure in pressure-induced folding/unfolding reactions demonstrates that novel information about the nature of protein folding transitions and transition states can be obtained from a combination of small-angle x-ray scattering using high intensity synchrotron radiation with the high pressure perturbation technique. C1 Univ Dortmund, Dept Chem Phys Chem 1, D-44221 Dortmund, Germany. Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Ctr Biochim Struct, F-34090 Montpellier, France. RP Winter, R (reprint author), Univ Dortmund, Dept Chem Phys Chem 1, Otto Hahn Str 6, D-44221 Dortmund, Germany. EM winter@steak.chemie.uni-dortmund.de RI Royer, Catherine/E-5266-2016; Littrell, Kenneth/D-2106-2013; OI Royer, Catherine/0000-0002-2670-3391; Littrell, Kenneth/0000-0003-2308-8618; Winter, Roland/0000-0002-3512-6928 NR 44 TC 80 Z9 81 U1 2 U2 8 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD MAR PY 2001 VL 80 IS 3 BP 1518 EP 1523 PG 6 WC Biophysics SC Biophysics GA 405VW UT WOS:000167182100042 PM 11222312 ER PT J AU Wong, KK Cheng, RS Mok, SC AF Wong, KK Cheng, RS Mok, SC TI Identification of differentially expressed genes from ovarian cancer cells by MICROMAX (TM) cDNA microarray system SO BIOTECHNIQUES LA English DT Article ID MOLECULAR-CLONING; EPITHELIAL-CELLS; OSTEOPONTIN; CARCINOMA; PATTERNS; PROTEIN; SERUM AB Using the MICROMAX(TM) cDNA microarray system, we were able to identify genes that are differentially overexpressed in ovarian cancer. A total of 30 putative genes, which are differentially overexpressed in ovarian cancer cell lines, were identified. The differential expression of some of these genes was further confirmed by real-time RT-PCR. Using this strategy, we have identified genes that either overexpress in all cancel cell lines or in only some cancer cell lines. Further characterization of these genes will allow them to be exploited in diagnosis, prognosis, anticancer therapy, and molecular classification of ovarian cancer. C1 Pacific NW Natl Lab, Mol Biosci, Richland, WA 99352 USA. Harvard Univ, Brigham & Womens Hosp, Sch Med, Lab Gynecol Oncol, Boston, MA 02115 USA. RP Wong, KK (reprint author), Pacific NW Natl Lab, Mol Biosci, P7-56,902 Battelle Blvd, Richland, WA 99352 USA. OI Wong, Kwong-Kwok/0000-0002-0375-6669 NR 16 TC 70 Z9 70 U1 0 U2 0 PU EATON PUBLISHING CO PI NATICK PA 154 E. CENTRAL ST, NATICK, MA 01760 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD MAR PY 2001 VL 30 IS 3 BP 670 EP 675 PG 6 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 408QU UT WOS:000167339800024 PM 11252802 ER PT J AU Rithidech, K Gordon, CR Cronkite, EP AF Rithidech, K Gordon, CR Cronkite, EP TI Telomerase activity in mouse myeloid leukemic cells and in cells from normal hematopoietic systems SO BLOOD CELLS MOLECULES AND DISEASES LA English DT Article DE telomerase; mouse; leukemia; radiation; blood; bone marrow ID IMMORTAL CELLS; HUMAN FIBROBLASTS; STEM-CELLS; ACTIVATION; TUMOR; CANCER; RNA; AGE; DIFFERENTIATION; LYMPHOCYTES AB The telomeric repeat amplification protocol (TRAP) assay was used to measure telomerase activity in radiation-induced mouse myeloid leukemic (ML) cells and in several populations of normal cells. A detectable level of telomerase activity was found in normal hematopoietic tissues, i.e., bone marrow (BM) cells, day 9 colony-forming unit spleen (CFU-S) colonies, peripheral blood (PB) lymphocytes, and spleen. The level of telomerase activity in normal BM cells was used as a background level. Nine of the I:! cases of ML had higher levels of activity than that of the normal BM cells and therefore they were scored as ML with positive telomerase. The other three cases were considered as ML with negative telomerase because the levels of the enzyme were equivalent to that of normal BM cells. The data indicate that cellular differentiation may suppress telomerase activity in mouse ML cells. In summary, the results suggest that the CBA/Ca mouse model should be a useful animal system for future studies on the assessment of telomerase activity in both malignant and normal hematopoietic cells. (C) 2001 Academic Press. C1 SUNY Stony Brook, Dept Pathol, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Rithidech, K (reprint author), SUNY Stony Brook, Dept Pathol, Stony Brook, NY 11794 USA. NR 41 TC 1 Z9 1 U1 1 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1079-9796 J9 BLOOD CELL MOL DIS JI Blood Cells Mol. Dis. PD MAR-APR PY 2001 VL 27 IS 2 BP 496 EP 504 DI 10.1006/bcmd.2001.0412 PG 9 WC Hematology SC Hematology GA 443VF UT WOS:000169361800022 PM 11500060 ER PT J AU Cayan, DR Kammerdiener, SA Dettinger, MD Caprio, JM Peterson, DH AF Cayan, DR Kammerdiener, SA Dettinger, MD Caprio, JM Peterson, DH TI Changes in the onset of spring in the western United States SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID NORTHERN-HEMISPHERE; ATMOSPHERIC CIRCULATION; MASS-BALANCE; CLIMATE VARIABILITY; SNOW COVER; TEMPERATURE; PACIFIC; PHENOLOGY; AMERICA; TRENDS AB Fluctuations in spring climate in the western United States over the last 4-5 decades are described by examining changes in the blooming of plants and the timing of snowmelt-runoff pulses. The two measures of spring's onset that are employed are the timing of first bloom of lilac and honeysuckle bushes from a long-term cooperative phenological network, and the timing of the first major pulse of snowmelt recorded from high-elevation streams. Both measures contain year-to-year fluctuations, with typical year-to year fluctuations at a given site of one to three weeks. These fluctuations are spatially coherent, forming regional patterns that cover most of the west. Fluctuations in lilac first bloom dates are highly correlated to those of honeysuckle, and both are significantly correlated with those of the spring snowmelt pulse. Each of these measures, then, probably respond to a common mechanism. Various analyses indicate that anomalous temperature exerts the greatest influence upon both interannual and secular changes in the onset of spring in these networks. Earlier spring onsets since the late 1970s are a remarkable feature of the records, and reflect the unusual spell of warmer-than-normal springs in western North America during this period. The warm episodes are clearly related to larger-scale atmospheric conditions across North America and the North Pacific, but whether this is predominantly an expression of natural variability or also a symptom of global warming is not certain. C1 Univ Calif San Diego, Scripps Inst Oceanog, Div Climate Res, La Jolla, CA 92093 USA. US Geol Survey, La Jolla, CA USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Montana State Univ, Bozeman, MT 59717 USA. US Geol Survey, Menlo Park, CA 94025 USA. RP Cayan, DR (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Div Climate Res, La Jolla, CA 92093 USA. NR 53 TC 480 Z9 490 U1 9 U2 104 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAR PY 2001 VL 82 IS 3 BP 399 EP 415 DI 10.1175/1520-0477(2001)082<0399:CITOOS>2.3.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 406RG UT WOS:000167228500001 ER PT J AU Bergeron, K AF Bergeron, K TI While no one was looking SO BULLETIN OF THE ATOMIC SCIENTISTS LA English DT Article C1 Sandia Natl Labs, Livermore, CA 94550 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU EDUC FOUNDATION NUCLEAR SCI PI CHICAGO PA 6042 SOUTH KIMBARK, CHICAGO, IL 60637 USA SN 0096-3402 J9 B ATOM SCI JI Bull. Atom. Scient. PD MAR-APR PY 2001 VL 57 IS 2 BP 42 EP 49 PG 8 WC International Relations; Social Issues SC International Relations; Social Issues GA 412GF UT WOS:000167546100021 ER PT J AU Guensch, GR Hardy, TB Addley, RC AF Guensch, GR Hardy, TB Addley, RC TI Examining feeding strategies and position choice of drift-feeding salmonids using an individual-based, mechanistic foraging model SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID HABITAT SUITABILITY CRITERIA; GRAYLING THYMALLUS-ARCTICUS; INSTREAM FLOW ASSESSMENT; RAINBOW-TROUT; MOUNTAIN STREAMS; INTERIOR ALASKA; ENERGETIC COST; SIZE; SELECTION; FISHES AB We demonstrated the ability of a mechanistic habitat selection model to predict habitat selection of brown trout (Salmo trutta) and mountain whitefish (Prosopium williamsoni) during summer and winter conditions in the Blacksmith Fork River, Utah. By subtracting energy costs and losses from the gross energy intake rate (GEI) obtained through simulation of prey capture, the model calculates the potential net energy intake rate (NEI) of a given stream position, which is essentially the rate of energy intake available for growth and reproduction. The prey capture model incorporates the size, swimming speed, and reaction distance of the fish; the velocity, depth, temperature, and turbidity of the water; and the density and size composition of the drifting invertebrates. The results suggest that during both summer and winter, the brown trout and mountain whitefish in our study reach avoided locations providing low NEI and preferred locations providing a high ratio of NEI to the swimming cost (SC) at the focal position of the fish (NEI/SC). This supports the idea that the drift-feeding fish in this study selected stream positions that provided adequate NEI for the least amount of swimming effort. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Utah State Univ, Inst Nat Syst Engn, Civil Environm Engn Dept, Logan, UT 84322 USA. RP Guensch, GR (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 32 TC 53 Z9 55 U1 2 U2 14 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD MAR PY 2001 VL 58 IS 3 BP 446 EP 457 DI 10.1139/cjfas-58-3-446 PG 12 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 409EK UT WOS:000167371400002 ER PT J AU Duell, EJ Millikan, RC Pittman, GS Winkel, S Lunn, RM Tse, CKJ Eaton, A Mohrenweiser, HW Newman, B Bell, DA AF Duell, EJ Millikan, RC Pittman, GS Winkel, S Lunn, RM Tse, CKJ Eaton, A Mohrenweiser, HW Newman, B Bell, DA TI Polymorphisms in the DNA repair gene XRCC1 and breast cancer SO CANCER EPIDEMIOLOGY BIOMARKERS & PREVENTION LA English DT Article ID BASE EXCISION-REPAIR; POLY(ADP-RIBOSE) POLYMERASE; LIGASE-III; CIGARETTE-SMOKING; DAMAGE; RISK; SUSCEPTIBILITY; PROTEIN; HUMANS; PROFICIENCY AB X-ray repair cross complementing group 1 (XRCC1) encodes a protein involved in base excision repair. We examined the association of polymorphisms in XRCC1 (codon 194 Arg --> Trp and codon 399 Arg --> Gln) and breast cancer in the Carolina Breast Cancer Study, a population-based case-control study in North Carolina. No association was observed between XRCC1 codon 194 genotype and breast cancer, and odds ratios (ORs) were not modified by smoking or radiation exposure. A positive association for XRCC1 codon 399 Arg/Gln or Gln/Gln genotypes compared with Arg/Arg was found among African Americans (253 cases, 266 controls; OR = 1,7, 95% confidence interval, 1,1-2,4) but not whites (386 cases, 381 controls; OR = 1,0, 95% confidence interval, 0,8-1,4), Among African-American women, ORs for the duration of smoking were elevated among women with XRCC1 codon 399 Arg/Arg genotype (trend test; P < 0.001) but not Arg/Gln or Gln/Gln (P = 0,23), There was no difference in OR for smoking according to XRCC1 codon 399 genotype in white women. ORs for occupational exposure to ionizing radiation were stronger for African-American and white women with codon 399 Arg/Arg genotype, High-dose radiation to the chest was more strongly associated with breast cancer among white women with XRCC1 codon 399 Arg/Arg genotype, Our results suggest that XRRC1 codon 399 genotype may influence breast cancer risk, perhaps by modifying the effects of environmental exposures. However, interpretation of our results is Limited by incomplete knowledge regarding the biological function of XRCC1 alleles. C1 Univ N Carolina, Sch Publ Hlth, Dept Epidemiol, Chapel Hill, NC 27599 USA. NIEHS, Lab Computat Biol & Risk Assessment, Res Triangle Pk, NC 27709 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Queensland Univ Technol, Sch Publ Hlth, Kelvin Grove, Qld 4059, Australia. Univ N Carolina, Sch Med, Lineberger Comprehens Canc Ctr, Chapel Hill, NC 27599 USA. RP Millikan, RC (reprint author), Univ N Carolina, Sch Publ Hlth, Dept Epidemiol, CB 7400, Chapel Hill, NC 27599 USA. FU NCI NIH HHS [P50-CA58223]; NIEHS NIH HHS [P-42-ES05948] NR 46 TC 210 Z9 221 U1 1 U2 4 PU AMER ASSOC CANCER RESEARCH PI PHILADELPHIA PA 615 CHESTNUT ST, 17TH FLOOR, PHILADELPHIA, PA 19106-4404 USA SN 1055-9965 J9 CANCER EPIDEM BIOMAR JI Cancer Epidemiol. Biomarkers Prev. PD MAR PY 2001 VL 10 IS 3 BP 217 EP 222 PG 6 WC Oncology; Public, Environmental & Occupational Health SC Oncology; Public, Environmental & Occupational Health GA 418BJ UT WOS:000167869600008 PM 11303590 ER PT J AU Li, L Borry, RW Iglesia, E AF Li, L Borry, RW Iglesia, E TI Reaction-transport simulations of non-oxidative methane conversion with continuous hydrogen removal - homogeneous-heterogeneous reaction pathways SO CHEMICAL ENGINEERING SCIENCE LA English DT Article DE methane; pyrolysis; kinetics; simulation; reaction engineering; membranes ID ETHYLENE; DEHYDROGENATION; AROMATIZATION; PYROLYSIS; CATALYSTS AB Detailed kinetic-transport models were used to explore thermodynamic and kinetic barriers in the non-oxidative conversion of CH4 via homogeneous and homogeneous-heterogeneous pathways and the effects of continuous hydrogen removal and of catalytic sites on attainable yields of useful C-2-C-10 products. The homogeneous kinetic model combines separately developed models for low-conversion pyrolysis and for chain growth to form large aromatics and carbon. The H-2 formed in the reaction decreases CH4 pyrolysis rates and equilibrium conversions and it favors the formation of lighter products. The removal of H-2 along tubular reactors with permeable walls increases reaction rates and equilibrium CH4 conversions. C-2-C-10 yields reach values greater than 90% at intermediate values of dimensionless transport rates (delta = 1-10), defined as the ratio hydrogen transport and methane conversion rates. Homogeneous reactions require impractical residence times, even with H-2 removal, because of slow initiation and chain transfer rates. The introduction of heterogeneous chain initiation pathways using surface sites that form methyl radicals eliminates the induction period without influencing the homogeneous product distribution. Methane conversion, however, occurs predominately in the chain transfer regime, within which individual transfer steps and the formation of C-2 intermediates become limited by thermodynamic constraints. Catalytic sites alone cannot overcome these constraints. Catalytic membrane reactors with continuous H, removal remove these thermodynamic obstacles and decrease the required residence time. Reaction rates become limited by homoeeneous reactions of C-2 products to form C6+ aromatics. Higher delta values lead to subuequznt conversion of the desired C-2-C-10 products to larger polynuclear aromatics. We conclude that catalytic methane pyrolysis at the low temperatures required for restricted chain growth and the elimination of thermodynamics constraints via continuous hydrogen removal provide a practical path for the direct conversion of methane to higher hydrocarbons. The rigorous design criteria developed are being implemented using shape-selective bifunctional pyrolysis catalysts and perovskite membrane films in a parallel experimental effort. (C) 2001 Elsevier Science Ltd, All rights reserved. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Chem Engn, 201,Gilman Hall 1462, Berkeley, CA 94720 USA. EM iglesia@cchem.berkeley.edu RI Iglesia, Enrique/D-9551-2017 OI Iglesia, Enrique/0000-0003-4109-1001 NR 32 TC 17 Z9 17 U1 1 U2 17 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0009-2509 EI 1873-4405 J9 CHEM ENG SCI JI Chem. Eng. Sci. PD MAR PY 2001 VL 56 IS 5 BP 1869 EP 1881 DI 10.1016/S0009-2509(00)00465-6 PG 13 WC Engineering, Chemical SC Engineering GA 420MT UT WOS:000168009300008 ER PT J AU Moore, JN Norman, DI Kennedy, BM AF Moore, JN Norman, DI Kennedy, BM TI Fluid inclusion gas compositions from an active magmatic-hydrothermal system: a case study of The Geysers geothermal field, USA SO CHEMICAL GEOLOGY LA English DT Article; Proceedings Paper CT 7th Biennial Pan-American Conference on Research on Fluid Inclusion (PACROFI VII) CY JUN 01-04, 1998 CL UNIV NEVADA, LAS VEGAS, NEVADA HO UNIV NEVADA DE fluid inclusions; gas analysis; The Geysers; geothermal; vapor-dominated; noble gases; crustal gas; magmatic gas; meteoric gas ID NORTHWEST GEYSERS; NOBLE-GASES; CALIFORNIA; RESERVOIR; ORIGIN; ISOTOPE; SPRINGS; CANADA AB Hydrothermal alteration and the active vapor-dominated geothermal system at The Geysers, CA are related to a composite hypabyssal granitic pluton emplaced beneath the field 1.1 to 1.2 million years ago. Deep drill holes provide a complete transect across the thermal system and samples of the modem-day steam. The hydrothermal system was liquid-dominated prior to formation of the modem vapor-dominated regime at 0.25 to 0.28 Ma. Maximum temperatures and salinities ranged from 440 degreesC and 44 wt.% NaCl equivalent in the biotite hornfels adjacent to the pluton to 305 degreesC and 5 wt.% NaCl equivalent at distances of 1730 m from the intrusive contact. The major, minor, and noble gas compositions of fluid inclusions in the hydrothermally altered rocks were integrated with microthermometric and mineralogic data to determine their sources and the effects of mixing and boiling. Major and minor gaseous species were released from the inclusions by crushing or thermal decrepitation; noble gases were released by crushing. The samples were analyzed by mass spectrometry. The analyses document the presence of magmatic, crustal, and meteoric components in the trapped fluids. Hydrothermal fluids present during the liquid-dominated phase of the system contained gaseous species derived mainly from crustal and magmatic sources. At The Geysers, N-2/Ar ratios greater than 525 and He-3/He-4 ratios of 6-10.7 Ra are diagnostic of a magmatic component. Crustal gas has CO2/CH4 ratios less than 4, N-2/Ar ratios between 45 and 525, and low 3He/4He ratios (0.5 Ra). Meteoric fluids have CO2/CH4 ratios greater than 4 and N2/Ar ratios between 38 (air-saturated water) and 84 (air). However, N-2/Ar ratios between 15 and 110 can result from boiling. Ratios less than 15 reflect the incorporation of N-2 into NH3-bearing clay minerals. In the central Geysers, the incursion of meteoric fluids occurred during the transition from the liquid- to vapor-dominated regime. Variations in the relative CH4, CO2, and H-2 contents of the gas analyses demonstrate that boiling took place under open-system conditions. The gas data indicate that the inclusions have remained closed to the diffusion of He and H-2 since their formation. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Utah, Energy & Geosci Inst, Salt Lake City, UT 84108 USA. New Mexico Inst Min & Technol, Dept Earth & Environm Sci, Socorro, NM 87801 USA. EO Lawrence Berkeley Natl Lab, Ctr Isotope Geochem, Berkeley, CA 94720 USA. RP Moore, JN (reprint author), Univ Utah, Energy & Geosci Inst, Salt Lake City, UT 84108 USA. NR 67 TC 36 Z9 47 U1 2 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD MAR 1 PY 2001 VL 173 IS 1-3 SI SI BP 3 EP 30 DI 10.1016/S0009-2541(00)00265-5 PG 28 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 405FJ UT WOS:000167147200002 ER PT J AU Suh, S Hoffman, DM Atagi, LM Smith, DC AF Suh, S Hoffman, DM Atagi, LM Smith, DC TI Atmospheric-pressure MOCVD of films containing zinc silicate SO CHEMICAL VAPOR DEPOSITION LA English DT Article DE AP-CVD; MOCVD; zinc amide precursors; zinc silicate ID CHEMICAL-VAPOR-DEPOSITION; GATE DIELECTRICS; THIN-FILMS; ORTHOSILICATE PHOSPHORS; TANTALUM PENTOXIDE; OPTICAL-PROPERTIES; PRECURSOR; ZIRCONIUM; HAFNIUM; ZN2SIO4-MN AB Thin films containing zinc silicate were prepared by metal-organic (MO) CVD, at substrate temperatures at or below 550 degreesC, by using the precursors Zn[N{Si(CH3)(3)}(2)](2) Or Zn[NC(CH3)(3){Si(CH3)(3)}](2), and O-2. In both cases, infrared (IR) data for the as-deposited films suggested they were composed of a mixture of SiO2 and material having Zn-O-Si linkages, and after lannealing, X-ray and IR data were consistent with the presence of crystalline Zn2SiO4 in the films. C1 Univ Houston, Dept Chem & Mat Res Ctr, Houston, TX 77204 USA. Univ Houston, Ctr Engn, Houston, TX 77204 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Suh, S (reprint author), Univ Houston, Dept Chem & Mat Res Ctr, Houston, TX 77204 USA. NR 31 TC 7 Z9 7 U1 1 U2 4 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0948-1907 J9 CHEM VAPOR DEPOS JI Chem. Vapor Depos. PD MAR PY 2001 VL 7 IS 2 BP 81 EP 84 DI 10.1002/1521-3862(200103)7:2<81::AID-CVDE81>3.0.CO;2-X PG 4 WC Electrochemistry; Materials Science, Coatings & Films; Physics, Condensed Matter SC Electrochemistry; Materials Science; Physics GA 415AX UT WOS:000167699300006 ER PT J AU Boxall, DL Deluga, GA Kenik, EA King, WD Lukehart, CM AF Boxall, DL Deluga, GA Kenik, EA King, WD Lukehart, CM TI Rapid synthesis of a Pt1Ru1/carbon nanocomposite using microwave irradiation: A DMFC anode catalyst of high relative performance SO CHEMISTRY OF MATERIALS LA English DT Article ID METHANOL FUEL-CELL; MOLECULAR PRECURSORS; METAL-CATALYSTS; CARBON; ELECTROOXIDATION; NANOPARTICLES; OXIDATION; ALLOY; ELECTROCATALYSIS; CLUSTERS AB Thermal treatment of (eta -C2H4)(Cl)Pt(mu -Cl)(2)Ru(Cl) (eta (3):eta (3)-2,7- dimethyloctadienediyl) (1)/ Vulcan carbon composites under appropriate oxidizing and reducing conditions using microwave dielectric loss heating affords PtRu/Vulcan carbon nanocomposites consisting of PtRu alloy nanoparticles highly dispersed on a powdered carbon support. Two such nanocomposites containing 16 or 50 wt % total metal and alloy nanoclusters of 3.4- or 5.4nm average diameter are formed within only 100 or 300 s of total microwave heating. XRD and on-particle EDS analyses reveal that complex 1 serves as a reliable single-source molecular precursor for the formation of PtRu nanoparticles having a nearly 1:1 metal alloy stoichiometry. Preliminary measurements of the catalytic activity of these nanocomposites as supported direct methanol fuel cell (DMFC) anode catalysts indicate that the 50 wt % nanocomposite has a performance superior to that of a 60 wt % commercial catalyst and a normalized performance equivalent to that of a proprietary unsupported Pt1Ru1 catalyst. C1 Vanderbilt Univ, Dept Chem, Nashville, TN 37235 USA. Univ Minnesota, Dept Chem Engn & Mat Sci, Corros Res Ctr, Minneapolis, MN 55455 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Lukehart, CM (reprint author), Vanderbilt Univ, Dept Chem, Box 1583, Nashville, TN 37235 USA. NR 47 TC 117 Z9 121 U1 6 U2 24 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD MAR PY 2001 VL 13 IS 3 BP 891 EP 900 DI 10.1021/cm000652m PG 10 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 414BN UT WOS:000167646200025 ER PT J AU Rudko, GY Long, VC Musfeldt, JL Koo, HJ Whangbo, MH Revcolevschi, A Dhalenne, G Bernholdt, DE AF Rudko, GY Long, VC Musfeldt, JL Koo, HJ Whangbo, MH Revcolevschi, A Dhalenne, G Bernholdt, DE TI Electronic transitions in doped and undoped copper germanate SO CHEMISTRY OF MATERIALS LA English DT Article ID SPIN-PEIERLS TRANSITION; MAGNETIC-PHASE-DIAGRAM; CUGEO3; SCATTERING; FIELD; SPECTROSCOPY; EXCITATIONS; COEXISTENCE; TEMPERATURE; COMPOUND AB We report an analysis of the absorption edge anisotropy in CuGeO3 based on a comparison of polarized optical data with electronic structure calculations in the framework of the extended Huckel tight binding model. Taking the z axis as parallel to the CuO4 chains, we ascribe the absorption edge in the magnetic chain direction to O 2p(x), 2p(y) --> singly filled Cu 3d transitions and the edge in the transverse direction to O 2p(z) --> singly filled Cu 3d excitations. The dual slope in the transverse direction is a direct consequence of the double maximum in the O 2p(z) density of states. The influence of Zn and Si doping on the electronic spectra of CuGeO3 is analyzed as well. Whereas neither impurity affects the phonon-assisted d-d band, Si doping smears the charge-transfer gap. This smearing of the gap by interchain impurity substitution is attributed to random distortions of the crystalline lattice giving rise to structurally induced changes in the electronic properties. C1 SUNY Binghamton, Dept Chem, Binghamton, NY 13902 USA. N Carolina State Univ, Dept Chem, Raleigh, NC 27695 USA. Univ Paris Sud, Lab Physicochim Solides, F-91405 Orsay, France. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Musfeldt, JL (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 34 TC 2 Z9 2 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD MAR PY 2001 VL 13 IS 3 BP 939 EP 944 DI 10.1021/cm000703f PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 414BN UT WOS:000167646200032 ER PT J AU Gash, AE Tillotson, TM Satcher, JH Poco, JF Hrubesh, LW Simpson, RL AF Gash, AE Tillotson, TM Satcher, JH Poco, JF Hrubesh, LW Simpson, RL TI Use of epoxides in the sol-gel synthesis of porous iron(III) oxide monoliths from Fe(III) salts SO CHEMISTRY OF MATERIALS LA English DT Article ID IRON-OXIDE; MAGNETIC-PROPERTIES; THIN-FILMS; OXIDATION; AEROGELS; NANOPARTICLES; ALPHA-FE2O3; TRANSITION; CATALYST; METHANOL AB Iron oxide-based porous solids were prepared by a sol-gel process using Fe(III) salts in various solvents. It was observed that the addition of propylene oxide to Fe(III) solutions resulted in the formation of transparent red-brown monolithic gels. The resulting gels were converted to either xerogels by atmospheric drying or aerogels by supercritical extraction with CO2(1). Some of the dried materials were characterized by nitrogen adsorption and desorption analysis and transmission electron microscopy (TEM). The results of those analyses indicate that the materials have high surface areas (similar to 300-400 m(2)/g), pore sizes with mesoporic dimensions (2-23 nm), and a microstructure made up of 5-10 nm diameter clusters of iron(III) oxide. The dependence of both gel formation and its rate was studied by varying the epoxide/Fe(III) ratio, the Fe(III) precursor salt, amount of water (H2O/Fe(III)) present, and the solvent employed. All of these variables were shown to affect the rate of gel formation and provide a convenient control of this parameter. Finally, an investigation of the mechanism of Fe2O3 gel formation was performed. Both pH and nuclear magnetic resonance (NMR) studies suggest that the added epoxide acts as an irreversible proton scavenger that induces the Fe(III) species to undergo hydrolysis and condensation to form an inorganic iron oxide framework. This method can be extended to prepare other transition and main-group metal oxide materials. C1 Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Lawrence Livermore Natl Lab, Energet Mat Ctr, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. EM gash2@llnl.gov NR 39 TC 279 Z9 293 U1 20 U2 161 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 EI 1520-5002 J9 CHEM MATER JI Chem. Mat. PD MAR PY 2001 VL 13 IS 3 BP 999 EP 1007 DI 10.1021/cm0007611 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 414BN UT WOS:000167646200041 ER PT J AU Cerchiai, BL Fiore, G Madore, J AF Cerchiai, BL Fiore, G Madore, J TI Geometrical tools for quantum Euclidean spaces SO COMMUNICATIONS IN MATHEMATICAL PHYSICS LA English DT Article ID DEFORMED PHASE-SPACE; DIFFERENTIAL-CALCULUS; POINCARE ALGEBRA; MINKOWSKI SPACE; FIELD-THEORY; LINEAR CONNECTIONS; SOQ(N) AB We apply one of the formalisms of noncommutative geometry to R-q(N), the quantum space covariant under the quantum group SOq(N). Over R-q(N) there are two SOq(N)-covariant differential calculi. For each we find a frame, a metric and two torsionfree covariant derivatives which are metric compatible up to a conformal factor and which have a vanishing linear curvature. This generalizes results found in a previous article for the case of R-q(3). As in the case N = 3, one has to slightly enlarge the algebra R-q(N); for N odd one needs only one new generator whereas for N even one needs two. As in the particular case N = 3 there is a conformal ambiguity in the natural metrics on the differential calculi over R-q(N). While in our previous article the frame was found "by hand", here we disclose the crucial role of the quantum group covariance and exploit it in the construction. As an intermediate step, we find a homomorphism from the cross product of R-q(N) with U(q)so(N) into R-q(N), an interesting result in itself. C1 Univ Munich, Sekt Phys, D-80333 Munich, Germany. Max Planck Inst Phys, D-80805 Munich, Germany. Univ Naples, Fac Ingn, Dipartimento Matemat & Applicaz, I-80125 Naples, Italy. Ist Nazl Fis Nucl, Sez Napoli, I-80125 Naples, Italy. Univ Paris Sud, Phys Theor & Hautes Energies Lab, F-91405 Orsay, France. RP Cerchiai, BL (reprint author), LBNL, MS 50A-5101,1 Cyclotron Rd, Berkeley, CA 94720 USA. OI Cerchiai, Bianca Letizia/0000-0002-0109-0330; Fiore, Gaetano/0000-0003-2503-7267 NR 39 TC 20 Z9 20 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0010-3616 J9 COMMUN MATH PHYS JI Commun. Math. Phys. PD MAR PY 2001 VL 217 IS 3 BP 521 EP 554 DI 10.1007/PL00005553 PG 34 WC Physics, Mathematical SC Physics GA 416VE UT WOS:000167800200004 ER PT J AU Owen, SJ AF Owen, SJ TI Hex-dominant mesh generation using 3D constrained triangulation SO COMPUTER-AIDED DESIGN LA English DT Article; Proceedings Paper CT 8th International Meshing Roundtable on Advances in Mesh Generation (8IMR) CY OCT 10-13, 1999 CL LAKE TAHOE, CALIFORNIA DE constrained triangulation; hexahedral-dominant; mesh generation ID DELAUNAY TRIANGULATION; BOUNDARY AB A method for decomposing a volume with a prescribed quadrilateral surface mesh, into a hexahedral-dominated mesh is proposed. With this method, known as Hex-Morphing (H-Morph), an initial tetrahedral mesh is provided. Tetrahedra are transformed and combined starting from the boundary and working towards the interior of the volume. The quadrilateral faces of the hexahedra are treated as internal surfaces, which can be recovered using constrained triangulation techniques. Implementation details of the edge and face recovery process are included. Examples and performance of the H-Morph algorithm are also presented. Published by Elsevier Science Ltd. C1 Sandia Natl Labs, Parallel Comp Sci Dept, Albuquerque, NM 87185 USA. RP Owen, SJ (reprint author), Sandia Natl Labs, Parallel Comp Sci Dept, POB 5800,MS 0847, Albuquerque, NM 87185 USA. NR 21 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0010-4485 J9 COMPUT AIDED DESIGN JI Comput.-Aided Des. PD MAR PY 2001 VL 33 IS 3 BP 211 EP 220 DI 10.1016/S0010-4485(00)00121-4 PG 10 WC Computer Science, Software Engineering SC Computer Science GA 405FL UT WOS:000167147400003 ER PT J AU Lu, Y Gadh, R Tautges, TJ AF Lu, Y Gadh, R Tautges, TJ TI Feature based hex meshing methodology: feature recognition and volume decomposition SO COMPUTER-AIDED DESIGN LA English DT Article; Proceedings Paper CT 8th International Meshing Roundtable on Advances in Mesh Generation (8IMR) CY OCT 10-13, 1999 CL LAKE TAHOE, CALIFORNIA DE feature recognition; FEA; solid modeling; hexahedral meshing; volume decomposition ID MEDIAL SURFACE SUBDIVISION; ELEMENT MESHES; GENERATION; ALGORITHM; SOLIDS; EDGES AB Considerable progress has been made on automatic hexahedral mesh generation in recent years. A few automated meshing algorithms (e.g. mapping, submapping, sweeping) have proven to be very reliable on certain classes of geometry. While it is always worth pursuing general algorithms viable on arbitrary geometry, a combination of the well-established algorithms is ready to take on classes of complicated geometry. By partitioning the entire geometry into meshable pieces matched with appropriate meshing algorithms, the original geometry becomes meshable and may achieve better mesh quality. Each meshable portion is recognized as a meshing feature. This paper, which is a part of the feature based meshing methodology, presents the work on shape recognition and volume decomposition to automatically decompose a CAD model into hex meshable volumes. There are four phases in this approach: Feature Determination to extract decomposition features; Cutting Surfaces Generation to form the cutting surfaces; Body Decomposition to get the imprinted volumes; and Meshing Algorithm Assignment to match volumes decomposed with appropriate meshing algorithms. This paper focuses on describing feature determination and volume decomposition; the last part has been described in another paper. The feature determination procedure is based on the CLoop feature recognition algorithm that is extended to be more general. Some decomposition and meshing results are demonstrated in the final section. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Wisconsin, Dept Mech Engn, I CARVE Lab, Madison, WI 53706 USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Lu, Y (reprint author), Univ Wisconsin, Dept Mech Engn, I CARVE Lab, 1500 Engn Dr, Madison, WI 53706 USA. NR 40 TC 32 Z9 40 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0010-4485 J9 COMPUT AIDED DESIGN JI Comput.-Aided Des. PD MAR PY 2001 VL 33 IS 3 BP 221 EP 232 DI 10.1016/S0010-4485(00)00122-6 PG 12 WC Computer Science, Software Engineering SC Computer Science GA 405FL UT WOS:000167147400004 ER PT J AU Hughes, R AF Hughes, R TI Quantum computation SO COMPUTING IN SCIENCE & ENGINEERING LA English DT Editorial Material RP Hughes, R (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1521-9615 J9 COMPUT SCI ENG JI Comput. Sci. Eng. PD MAR-APR PY 2001 VL 3 IS 2 BP 26 EP 26 DI 10.1109/MCISE.2001.908998 PG 1 WC Computer Science, Interdisciplinary Applications SC Computer Science GA 405BA UT WOS:000167136300007 ER PT J AU Hoover, WG Hoover, CG AF Hoover, WG Hoover, CG TI SPAM-based recipes for continuum simulations SO COMPUTING IN SCIENCE & ENGINEERING LA English DT Editorial Material ID PARTICLE APPLIED MECHANICS; MOLECULAR-DYNAMICS; EXPANSIONS C1 Univ Calif Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94551 USA. Univ Calif Lawrence Livermore Natl Lab, Methods Dev Grp, Dept Mech Engn, Livermore, CA 94551 USA. RP Hoover, WG (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Appl Sci, L-794, Livermore, CA 94551 USA. NR 6 TC 8 Z9 8 U1 1 U2 4 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1521-9615 J9 COMPUT SCI ENG JI Comput. Sci. Eng. PD MAR-APR PY 2001 VL 3 IS 2 BP 78 EP 85 DI 10.1109/5992.909007 PG 10 WC Computer Science, Interdisciplinary Applications SC Computer Science GA 405BA UT WOS:000167136300016 ER PT J AU Liu, K Pan, WP Riley, JT Wright, IG Ho, KK Mehta, AK Smith, SR AF Liu, K Pan, WP Riley, JT Wright, IG Ho, KK Mehta, AK Smith, SR TI The effects of ash deposits on high-temperature corrosion of alloys in a fluidized bed combustion system SO CORROSION LA English DT Article DE chlorine; deposits; fluidized bed combustion; sulfur AB Five 1,000-h combustion tests firing 5 different coals were conducted in a 0.1-MWth-fluidized bed combustion (FBC) facility at Western Kentucky University (WKU) with the operating conditions simulating those of the FBC unit at the Tennessee Valley Authority's (TVA) Shawnee Power Station. Five coals were selected with various S and Cl contents ranging from high S (4.48%) arid high Cl (0.47%) to low S (0.97%) and low Cl (0.012%). Three types of uncooled steel coupons (Types 304 [UNS S30400], 309 [UNS S30900], and 347 [UNS S34700] stainless steel [SS]) were prepared and installed, based on the advice of TVA, to simulate the evaporator tubes in the superheater region (550degreesC to 600degreesC [1,020degreesF to 1,100degreesF]), Metal wastage of each coupon was determined by measuring the thickness before and after each combustion test, In order to Study the relationship between metal corrosion and ash deposits, a total of 170 ash deposits were collected from the test coupon surfaces during the 5,000-h testing and analyzed. The major components in the deposits were Ca-based compounds, with S content similar to10% to 15%, and chloride content similar to0.5% to 5%. It was concluded that the Ca sorbent in the FBC system can capture not only the S but also the chloride effectively, and as a result decrease the gas phase chloride concentration in the FBC system down to a level of < 60 ppm. The concentration is unlikely to have contributed much to corrosion of the metal in the FBC system. Alkali metals (K and Na) were observed only on the surface of the alloys. High S contents were found in the outer part of the deposits and appeared to be associated with Cc and Mg, suggesting that the fly ash may have reacted further after being deposited on the surface of the metal. There was good agreement between locations of high-S concentrations and high-Cr content in the inner layers of the corrosion scale on the samples, indicating that corrosion involved sulfidation attack. S is the major element causing corrosion of the metal. C1 Western Kentucky Univ, Dept Chem, Combust Lab, Bowling Green, KY 42101 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Illinois Clean Coal Inst, Carterville, IL 62918 USA. Elect Power Res Inst, Palo Alto, CA 94304 USA. Tennessee Valley Author, Chattanooga, TN 37402 USA. RP Liu, K (reprint author), Western Kentucky Univ, Dept Chem, Combust Lab, Bowling Green, KY 42101 USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 USA SN 0010-9312 J9 CORROSION JI Corrosion PD MAR PY 2001 VL 57 IS 3 BP 253 EP 264 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 565EK UT WOS:000176355900006 ER PT J AU Snell, EH Judge, RA Crawford, L Forsythe, EL Pusey, ML Sportiello, M Todd, P Bellamy, H Lovelace, J Cassanto, JM Borgstahl, GEO AF Snell, EH Judge, RA Crawford, L Forsythe, EL Pusey, ML Sportiello, M Todd, P Bellamy, H Lovelace, J Cassanto, JM Borgstahl, GEO TI Investigating the effect of impurities on macromolecule crystal growth in microgravity SO CRYSTAL GROWTH & DESIGN LA English DT Article ID EGG-WHITE LYSOZYME; PROTEIN CRYSTAL; THAUMATIN CRYSTALS; CRYSTALLIZATION; TEMPERATURE; PURIFICATION; SPACEHAB-01; RESOLUTION; PERFECTION; APPARATUS AB Chicken egg-white lysozyme (CEWL) crystals were grown in microgravity and on the ground in the presence of various amounts of a naturally occurring lysozyme dimer impurity. No significant favorable differences in impurity incorporation between microgravity and ground crystal samples were observed. At low impurity concentration the microgravity crystals preferentially incorporated the dimer. The presence of the dimer in the crystallization solutions in microgravity reduced crystal size, increased mosaicity, and reduced the signal-to-noise ratio of the X-ray data. Microgravity samples proved more sensitive to impurity. Accurate indexing of the reflections proved critical to the X-ray analysis. The largest crystals with the best X-ray diffraction properties were grown from pure solution in microgravity. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Univ Colorado, Dept Chem Engn, Boulder, CO 80309 USA. Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. Univ Toledo, Dept Chem, Toledo, OH 43606 USA. Instrumentat Technol Associates, Exton, PA 19341 USA. RP Snell, EH (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 44 TC 28 Z9 28 U1 2 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1528-7483 J9 CRYST GROWTH DES JI Cryst. Growth Des. PD MAR-APR PY 2001 VL 1 IS 2 BP 151 EP 158 DI 10.1021/cg0055474 PG 8 WC Chemistry, Multidisciplinary; Crystallography; Materials Science, Multidisciplinary SC Chemistry; Crystallography; Materials Science GA 519CJ UT WOS:000173707100008 ER PT J AU Hou, VC Conboy, JG AF Hou, VC Conboy, JG TI Regulation of alternative pre-mRNA splicing during erythroid differentiation SO CURRENT OPINION IN HEMATOLOGY LA English DT Article ID ACTIN-BINDING DOMAIN; HUMAN ANKYRIN-1 GENE; MESSENGER-RNA; PROTEIN 4.1; BETA-SPECTRIN; HEREDITARY SPHEROCYTOSIS; SKELETAL PROTEIN-4.1; MULTIPLE ISOFORMS; MEMBRANE-PROTEIN; TERNARY COMPLEX AB Although the mature enucleated erythrocyte is no longer active in nuclear processes such as pre-mRNA splicing, the function of many of its major structural proteins is dependent on alternative splicing choices made during the earlier stages of erythropoiesis. These splicing decisions fundamentally regulate many aspects of protein structure and function by governing the inclusion or exclusion of exons that encode protein interaction domains, regulatory signals, or translation initiation or termination sites. Alternative splicing events may be partially or entirely erythroid-specific, ie, distinct from the splicing patterns imposed on the same transcripts in nonerythroid cells. Moreover, differentiation stage-specific splicing "switches" may alter the structure and function of erythroid proteins in physiologically important ways as the cell is morphologically and functionally remodeled during normal differentiation, Derangements in the splicing of individual mutated pre-mRNAs can produce synthesis of truncated or unstable proteins that are responsible for numerous erythrocyte disorders. This review will summarize the salient features of regulated alternative splicing in general, review existing information concerning the widespread extent of alternative splicing among erythroid genes, and describe recent studies that are beginning to uncover the mechanisms that regulate an erythroid splicing switch in the protein 4.1R gene. (C) 2001 Lippincott Williams & Wilkins, Inc. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Conboy, JG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Mailstop74-157,1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [R01 HL045182] NR 86 TC 14 Z9 14 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1065-6251 J9 CURR OPIN HEMATOL JI Curr. Opin. Hematol. PD MAR PY 2001 VL 8 IS 2 BP 74 EP 79 DI 10.1097/00062752-200103000-00003 PG 6 WC Hematology SC Hematology GA 446RZ UT WOS:000169527400003 PM 11224680 ER PT J AU Haldar, K Samuel, BU Mohandas, N Harrison, T Hiller, NL AF Haldar, K Samuel, BU Mohandas, N Harrison, T Hiller, NL TI Erythrocytic vacuolar rafts induced by malaria parasites SO CURRENT OPINION IN HEMATOLOGY LA English DT Article ID GPI-ANCHORED PROTEINS; RED-BLOOD-CELLS; PLASMODIUM-FALCIPARUM EXPORTS; INFECTED ERYTHROCYTES; MEMBRANE; CHANNEL; CHOLESTEROL; TRANSPORT; CYTOPLASM; ULTRASTRUCTURE AB Studies in the past year displaced long-standing dogmas and provided many new molecular insights into how proteins and solutes move between the erythrocyte plasma membrane and the malarial vacuole. Highlights include a demonstration that (1) detergent-resistant membrane (DRM) rafts exist in the red cell membrane and their resident proteins are detected as rafts in the plasmodial vacuole, (2) a voltage-gated channel in the infected red cell membrane mediates uptake of extracellular nutrient solutes, and (3) intraerythrocytic membranes transport a parasite-encoded adherence antigen to the red cell surface. (C) 2001 Lippincott Williams & Wilkins, Inc. C1 Northwestern Univ, Dept Pathol, Chicago, IL 60611 USA. Northwestern Univ, Dept Microbiol Immunol, Chicago, IL 60611 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Haldar, K (reprint author), Northwestern Univ, Dept Pathol, 303 E Chicago Ave, Chicago, IL 60611 USA. RI Haldar, Kasturi/C-6685-2014; Hiller, N. Luisa/A-3739-2016 OI Hiller, N. Luisa/0000-0001-6572-1368 FU NIAID NIH HHS [AI39071]; NIDDK NIH HHS [DK32094] NR 40 TC 7 Z9 7 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1065-6251 J9 CURR OPIN HEMATOL JI Curr. Opin. Hematol. PD MAR PY 2001 VL 8 IS 2 BP 92 EP 97 DI 10.1097/00062752-200103000-00006 PG 6 WC Hematology SC Hematology GA 446RZ UT WOS:000169527400006 PM 11224683 ER PT J AU Edwards, BS Kuckuck, FW Prossnitz, ER Okun, A Ransom, JT Sklar, LA AF Edwards, BS Kuckuck, FW Prossnitz, ER Okun, A Ransom, JT Sklar, LA TI Plug flow cytometry extends analytical capabilities in cell adhesion and receptor pharmacology SO CYTOMETRY LA English DT Article; Proceedings Paper CT 2nd Sam Latt Conference on Signalling for Life and Death: Cytometry in the Analysis and Modelling of Cell Signalling CY JUL 18-21, 1999 CL HAMILTON ISL, AUSTRALIA DE flow cytometry; automation; sample handling; cell adhesion ID P-SELECTIN; NEUTROPHILS; KILLER; CA-2+ AB Background: Plug flow cytometry is a recently developed system for the automated delivery of multiple small boluses or "plugs" of cells or particles to the flow cytometer for analysis. Important system features are that sample plugs are of precisely defined volume and that the sample vessel need not be pressurized. We describe how these features enable direct cell concentration determinations and novel ways to integrate flow cytometers with other analytical instruments. Methods: Adhesion assays employed human polymorphonuclear neutrophils (PMNs) loaded with Fura Red and Chinese hamster ovary (CHO) cells cotransfected with genes for green fluorescent protein (GFP) and human P-selectin. U937 cells expressing the human 7-transmembrane formyl peptide receptor were loaded with the fluorescent probe indo-1 for intracellular ionized calcium determinations. A computer-controlled syringe or peristaltic pump loaded the sample into a sample loop of the plug now coupler, a reciprocating eight-port valve. When the valve position was switched, the plug of sample in the sample loop was transported to the flow cytometer by a pressure-driven fluid line. Results: In stirred mixtures of PMNs and CHO cells, we used plug flow cytometry to directly quantify changes in concentrations of nonadherent singlet PMNs. This approach enabled accurate quantification of adherent PMNs in multicell aggregates. We constructed a novel plug flow interface between the flow cytometer and a cone-plate viscometer to enable real-time flow cytometric analysis of cell-cell adhesion under conditions of uniform shear. The High Throughput Pharmacology System (HTPS) is an instrument used for automated programming of complex pharmacological cell treatment protocols. It was interfaced via the plug flow coupling device to enable rapid (<5 min) flow cytometric characterization of the intracellular calcium dose-response profile of U937 cells to formyl peptide. Conclusions: By facilitating the coupling of flow cytometers to other fluidics-based analytical instruments, plug flow cytometry has extended analytical capabilities in cell adhesion and pharmacological characterization of receptor-ligand interactions. C1 Univ New Mexico, Hlth Sci Ctr, Dept Pathol, Canc Res & Treatment Ctr, Albuquerque, NM 87131 USA. Univ New Mexico, Hlth Sci Ctr, Dept Cell Biol & Physiol, Canc Res & Treatment Ctr, Albuquerque, NM 87131 USA. Axiom Biotechnol Inc, San Diego, CA USA. Los Alamos Natl Labs, Los Alamos, NM USA. RP Edwards, BS (reprint author), Univ New Mexico, Hlth Sci Ctr, Dept Pathol, Canc Res & Treatment Ctr, CRF Room 217,2325 Camino Salud, Albuquerque, NM 87131 USA. RI Prossnitz, Eric/B-4543-2008 FU NCRR NIH HHS [RR14175, RR01315]; NHLBI NIH HHS [HL56384] NR 14 TC 18 Z9 19 U1 0 U2 3 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0196-4763 J9 CYTOMETRY JI Cytometry PD MAR 1 PY 2001 VL 43 IS 3 BP 211 EP 216 DI 10.1002/1097-0320(20010301)43:3<211::AID-CYTO1052>3.0.CO;2-3 PG 6 WC Biochemical Research Methods; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 404JC UT WOS:000167092800010 PM 11170109 ER PT J AU Jimenez, I Gago, R Albella, JM Terminello, LJ AF Jimenez, I Gago, R Albella, JM Terminello, LJ TI X-Ray absorption studies of bonding environments in graphitic carbon nitride SO DIAMOND AND RELATED MATERIALS LA English DT Article; Proceedings Paper CT 11th European Conference on Diamond, Diamond-like Materials, Carbon Nanotubes, Nitrides and Silicon Carbide (Diamond 2000) CY SEP 03-08, 2000 CL OPORTO, PORTUGAL SP De Beers Ind Diamonds (UK) Ltd, GFD Gesell Diamantprod mbH, Philips Res Labs, Elsevier Sci DE carbon nitride; XANES; NEXAFS; bonding ID AMORPHOUS-CARBON; THIN-FILMS; MAGNETRON AB In this work we discuss the number of different bonding environments present in graphitic carbon nitride films, that can be resolved by X-ray absorption near edge spectroscopy (XANES). The carbon and nitrogen features are related by comparing spectra with very distinct relative intensities of the different peaks. The effect on the bonding configuration of different N/C ratio in the films, substrate temperature during film growth and post-deposition annealing is also studied. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CSIC, Inst Ciencia Mat, E-28049 Madrid, Spain. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Jimenez, I (reprint author), CSIC, Inst Ciencia Mat, E-28049 Madrid, Spain. RI Jimenez, Ignacio/F-7422-2010; Gago, Raul/C-6762-2008 OI Jimenez, Ignacio/0000-0001-5605-3185; Gago, Raul/0000-0003-4388-8241 NR 14 TC 19 Z9 20 U1 3 U2 10 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD MAR-JUL PY 2001 VL 10 IS 3-7 SI SI BP 1170 EP 1174 DI 10.1016/S0925-9635(00)00383-6 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 432ZJ UT WOS:000168730600166 ER PT J AU Catellani, A Galli, G AF Catellani, A Galli, G TI Defects at the carbon terminated SiC(001) surface SO DIAMOND AND RELATED MATERIALS LA English DT Article; Proceedings Paper CT 11th European Conference on Diamond, Diamond-like Materials, Carbon Nanotubes, Nitrides and Silicon Carbide (Diamond 2000) CY SEP 03-08, 2000 CL OPORTO, PORTUGAL SP De Beers Ind Diamonds (UK) Ltd, GFD Gesell Diamantprod mbH, Philips Res Labs, Elsevier Sci DE 3C-SiC; defect; computer simulation; scanning tunneling microscopy ID CUBIC SILICON-CARBIDE; BETA-SIC(100) SURFACE; NATIVE DEFECTS; 1ST-PRINCIPLES CALCULATIONS; ELECTRONIC-STRUCTURE; RECONSTRUCTION; VACANCY AB We present first principle molecular dynamics simulations for selected point defects on the (001) stoichiometric carbon terminated surface of cubic silicon carbide. In particular we investigated missing units and coordination defects. The results of our calculations are compared with recent experiments, in particular we discuss simulated STM images, which are in good agreement with measured ones. (C) 2001 Elsevier Science B.V. All rights reserved. C1 MASPEC, CNR, I-43010 Parma, Italy. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP MASPEC, CNR, Parco Nazl Sci 37A, I-43010 Parma, Italy. EM catellani@maspec.bo.cnr.it OI Catellani, Alessandra/0000-0001-5197-7186 NR 29 TC 4 Z9 4 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 EI 1879-0062 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD MAR-JUL PY 2001 VL 10 IS 3-7 SI SI BP 1259 EP 1263 DI 10.1016/S0925-9635(00)00449-0 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 432ZJ UT WOS:000168730600185 ER PT J AU Farmer, A James, JR McDonald, JA O'Neill, R AF Farmer, A James, JR McDonald, JA O'Neill, R TI Rethinking the optimal level of environmental quality: justifications for strict environmental policy SO ECOLOGICAL ECONOMICS LA English DT Article DE environmental policy; game-theoretic model; ecological complexity; environmental benefits; environmental damages; ecological services ID IRREVERSIBILITY; WORLDS AB Traditional environmental theory suggests that the optimal level of a pollution emission occurs when the marginal damage created by the emissions is equal to the marginal cost of reducing the emissions. We argue that the benefits from reducing pollution should be much more broadly defined to include at least three other sources of benefits. First, we develop a game-theoretic model in which firms may under-invest in cost-saving green technologies'. Second, we demonstrate that consideration of future damages and abatement costs leads to a lower current optimal pollution level than that obtained in traditional models. Finally, we show that ecological complexity creates indirect pathways by which greater pollution increases the likelihood of generating irreversible environmental damage. This broader definition of the benefits of pollution abatement yields an optimal level of pollution that may actually be less than the level at which conventionally-measured marginal damages are equal to marginal abatement costs. Thus, environmental policy should be stricter. (C) 2001 Elsevier Science B.V. All lights reserved. C1 Lehigh Univ, Dept Econ, Bethlehem, PA 18105 USA. Univ Arkansas, Dept Econ, Fayetteville, AR 72701 USA. Washington & Lee Univ, Environm Studies Program, Lexington, VA 24450 USA. Washington & Lee Univ, Dept Econ, Lexington, VA 24450 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP McDonald, JA (reprint author), Lehigh Univ, Dept Econ, 621 Taylor St, Bethlehem, PA 18105 USA. NR 24 TC 4 Z9 4 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8009 J9 ECOL ECON JI Ecol. Econ. PD MAR PY 2001 VL 36 IS 3 BP 461 EP 473 DI 10.1016/S0921-8009(00)00244-5 PG 13 WC Ecology; Economics; Environmental Sciences; Environmental Studies SC Environmental Sciences & Ecology; Business & Economics GA 409QQ UT WOS:000167394700008 ER PT J AU Braun, A Seifert, S Thiyagarajan, P Cramer, SP Cairns, EJ AF Braun, A Seifert, S Thiyagarajan, P Cramer, SP Cairns, EJ TI In situ anomalous small angle X-ray scattering and absorption on an operating rechargeable lithium ion battery cell SO ELECTROCHEMISTRY COMMUNICATIONS LA English DT Article DE ASAXS; microstructure; lithium battery; in situ ID LIMN2O4; PHASE AB We have employed anomalous small angle X-ray scattering (ASAXS) and X-ray absorption in situ on an operating lithium ion battery, cell with LiMn2O4 as the positive electrode material. Manganese K-edge absorption spectra and scattering patterns were recorded at various stages of charge between 3.8 and 4.5 V. The shift of the manganese absorption K-edge was observed as a function of the charge of the electrode, Clear changes in the microstructure of the spinel at the 4V plateau was observed even during the first charging cycle. (C) 2001 Published by Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Braun, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, MS 70-108B,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI BRAUN, Artur/A-1154-2009; Cairns, Elton/E-8873-2012 OI BRAUN, Artur/0000-0002-6992-7774; Cairns, Elton/0000-0002-1179-7591 NR 15 TC 8 Z9 9 U1 2 U2 8 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1388-2481 J9 ELECTROCHEM COMMUN JI Electrochem. Commun. PD MAR PY 2001 VL 3 IS 3 BP 136 EP 141 DI 10.1016/S1388-2481(01)00121-7 PG 6 WC Electrochemistry SC Electrochemistry GA 419MX UT WOS:000167953800007 ER PT J AU Sutherland, JC Monteleone, DC Trunk, JG Bennett, PV Sutherland, BM AF Sutherland, JC Monteleone, DC Trunk, JG Bennett, PV Sutherland, BM TI Quantifying DNA damage by gel electrophoresis, electronic imaging and number-average length analysis SO ELECTROPHORESIS LA English DT Article DE electronic imaging; DNA damage and repair; agarose gel electrophoresis ID BROMIDE-STAINED DNA; AGAROSE GELS; ETHIDIUM-BROMIDE; STRAND BREAKS; IONIZING-RADIATION; PYRIMIDINE DIMERS; RELATING MOBILITY; HUMAN-CELLS; FIELD; FLUORESCENCE AB DNA damages that can be converted to single- or double strand breaks can be quantified by separating DNA by gel electrophoresis and obtaining a quantitative image of the resulting distribution of DNA in the gel. We review the theory of this method and discuss its implementation, including the charge-coupled device (CCD) camera systems we developed to acquire images of fluorophore labeled DNA. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Sutherland, JC (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. FU NCRR NIH HHS [RR07338]; NHGRI NIH HHS [HG00371] NR 40 TC 33 Z9 36 U1 0 U2 6 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD MAR PY 2001 VL 22 IS 5 BP 843 EP 854 DI 10.1002/1522-2683()22:5<843::AID-ELPS843>3.0.CO;2-9 PG 12 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 422BK UT WOS:000168097900007 PM 11332751 ER PT J AU Kumaran, D Eswaramoorthy, S Luft, BJ Koide, S Dunn, JJ Lawson, CL Swaminathan, S AF Kumaran, D Eswaramoorthy, S Luft, BJ Koide, S Dunn, JJ Lawson, CL Swaminathan, S TI Crystal structure of outer surface protein C (OspC) from the Lyme disease spirochete, Borrelia burgdorferi SO EMBO JOURNAL LA English DT Article DE Lyme disease; OspC; 3D structure; X-ray diffraction ID MULTIPLE ISOMORPHOUS REPLACEMENT; DIFFERENTIAL EXPRESSION; DIFFRACTION DATA; SENSU-STRICTO; INFECTION; MICE; DIVERSITY; ANTIGENS; BINDING; GENE AB Outer surface protein C (OspC) is a major antigen on the surface of the Lyme disease spirochete, Borrelia burgdorferi, when it is being transmitted to humans. Crystal structures of OspC have been determined for strains HB19 and B31 to 1.8 and 2.5 Angstrom resolution, respectively. The three-dimensional structure is predominantly helical. This is in contrast to the structure of OspA, a major surface protein mainly present when spirochetes are residing in the midgut of unfed ticks, which is mostly P-sheet. The surface of OspC that would project away from the spirochete's membrane has a region of strong negative electrostatic potential which may be involved in binding to positively charged host ligands. This feature is present only on OspCs from strains known to cause invasive human disease. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. SUNY Stonybrook, Sch Med, Div Infect Dis, Stony Brook, NY USA. Univ Rochester, Med Ctr, Dept Biochem & Biophys, Rochester, NY 14642 USA. Rutgers State Univ, Dept Chem, Piscataway, NJ 08854 USA. RP Swaminathan, S (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. OI Luft, Benjamin/0000-0001-9008-7004 FU NIAID NIH HHS [AI37256]; NINDS NIH HHS [P01-NS34092-01A2] NR 44 TC 70 Z9 70 U1 0 U2 2 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0261-4189 J9 EMBO J JI Embo J. PD MAR 1 PY 2001 VL 20 IS 5 BP 971 EP 978 DI 10.1093/emboj/20.5.971 PG 8 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 409QG UT WOS:000167393900005 PM 11230121 ER PT J AU Greening, LA Ting, M Krackler, TJ AF Greening, LA Ting, M Krackler, TJ TI Effects of changes in residential end-uses and behavior on aggregate carbon intensity: comparison of 10 OECD countries for the period 1970 through 1993 SO ENERGY ECONOMICS LA English DT Article DE residential; energy use; carbon dioxide emissions ID ENERGY USE; EFFICIENCY; DECOMPOSITION; SECTOR AB Patterns of the evolution of aggregate carbon intensity from residential end uses show greater variability than other sectors. For some countries in this analysis, this measure exhibits significant decreases, while for other countries this measure exhibits significant increases over the period of analysis. The Adaptive Weighted Divisia rolling base year index specification is applied to carbon emissions from the residential sector for 10 OECD countries,for the period 1970-1993. Decreases in aggregate carbon intensity for six of the countries range less than 8% to almost 72%, and may be attributed to changes in three different factors. However, for all of the countries, decreases are offset by shifts in end-use structure toward more carbon-intensive activities. These shifts are driven by an increase in the number of households with a corresponding increase in floor space, acquisition of greater numbers of major appliances and by an increase in the 'other' energy consumption category. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Natl Lab, Div Energy & Environm, Berkeley, CA 94720 USA. RP Greening, LA (reprint author), 7780 Marshall Heights Court, Falls Church, VA 22043 USA. NR 21 TC 29 Z9 37 U1 3 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0140-9883 J9 ENERG ECON JI Energy Econ. PD MAR PY 2001 VL 23 IS 2 BP 153 EP 178 DI 10.1016/S0140-9883(00)00059-1 PG 26 WC Economics SC Business & Economics GA 410NZ UT WOS:000167447200003 ER PT J AU Huang, HP Shi, Y Li, W Chang, SG AF Huang, HP Shi, Y Li, W Chang, SG TI Dual alkali approaches for the capture and separation of CO2 SO ENERGY & FUELS LA English DT Article; Proceedings Paper CT ACS Division of Fuel Chemistry Symposium on CO2 Capture, Utilization, and Sequestration at the National Meeting of the American-Chemical-Society CY AUG 20-24, 2000 CL WASHINGTON, D.C. SP Amer Chem Soc ID CARBON-DIOXIDE; ABSORPTION AB The Solvay process utilizes two alkalis in sequential order to convert CO2 to sodium carbonate for commercial use. The ability to transform CO2 into sodium carbonate cost-effectively would be a breakthrough in CO2 sequestration by providing benign long-term storage of CO2. However, the Solvay process was not designed for CO2 sequestration and is not practical for use in the sequestration of CO2 from fossil fuel power plants. This paper investigates methods to modify the process in order to make it effective for the control of power plant CO2 emissions. The new modified process, called the Dual Alkali Approach, attempts to replace either or both bases, ammonia and lime, in the Solvay process with other compounds to make CO2 capture and separation efficient. Ammonia was replaced with different amines in aqueous solutions of salts and it was found that bicarbonate precipitation did occur. A method to regenerate the amine in the second step has not been implemented. However, the second step in the Solvay Process has been implemented without using lime, namely, ammonia has been regenerated from an ammonium chloride solution using activated carbon. The HCl adsorbed in the activated carbon was removed by water to regenerate the activated carbon. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Chang, SG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 10 TC 50 Z9 52 U1 2 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAR-APR PY 2001 VL 15 IS 2 BP 263 EP 268 DI 10.1021/ef0002400 PG 6 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 414MC UT WOS:000167669600004 ER PT J AU Yeh, JT Pennline, HW AF Yeh, JT Pennline, HW TI Study of CO2 absorption and desorption in a packed column SO ENERGY & FUELS LA English DT Article; Proceedings Paper CT ACS Division of Fuel Chemistry Symposium on CO2 Capture, Utilization, and Sequestration at the National Meeting of the American-Chemical-Society CY AUG 20-24, 2000 CL WASHINGTON, D.C. SP Amer Chem Soc AB Carbon dioxide, a major greenhouse gas, may need to be removed from flue gas produced by combustion of fossil fuels in order to manage future climate changes. Although conventional wet scrubbing techniques exist for removal of carbon dioxide from gas streams, the wet scrubbing techniques must improve to process large volumes of flue gas at acceptable thermal efficiencies and minimal costs. Amine scrubbing is one such technique to remove CO2. To make the process more efficient, various areas of improvement were investigated: gas-liquid contacting area, the type of reactant, and dilution of the aqueous fraction with organic liquids. Pertaining to the former, various absorption tests with conventional packing material and structured packings were conducted with mono-ethanolamine (MEA), a traditional solvent, as well as with novel amines. Significant improvements in CO2 removal were obtained with the structured packing. With respect to the amine investigation, a key to improved efficiency is the ease of regeneration of the CO2-loaded absorbent. Testing with a sterically hindered amine, 2-amino-2-methyl-1-propanol, revealed that, although absorption was somewhat less as compared to MEA, thermal regeneration was far easier. In addition, the effect of organic diluent on CO2 absorption capacity of MEA solution is determined. The impact of various process parameters on the absorption and desorption steps will also be discussed. C1 US DOE, Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. Parsons Project Serv Inc, Pittsburgh, PA 15236 USA. RP Yeh, JT (reprint author), US DOE, Natl Energy Technol Lab, POB 10949, Pittsburgh, PA 15236 USA. NR 8 TC 100 Z9 106 U1 3 U2 31 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAR-APR PY 2001 VL 15 IS 2 BP 274 EP 278 DI 10.1021/ef0002389 PG 5 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 414MC UT WOS:000167669600006 ER PT J AU Siriwardane, RV Shen, MS Fisher, EP Poston, JA AF Siriwardane, RV Shen, MS Fisher, EP Poston, JA TI Adsorption of CO2 on molecular sieves and activated carbon SO ENERGY & FUELS LA English DT Article; Proceedings Paper CT ACS Division of Fuel Chemistry Symposium on CO2 Capture, Utilization, and Sequestration at the National Meeting of the American-Chemical-Society CY AUG 20-24, 2000 CL WASHINGTON, D.C. SP Amer Chem Soc ID ZINC AB Pressure swing adsorption (PSA) and temperature swing adsorption (TSA) are some of the potential techniques that could be applicable for removal of CO2 from high-pressure fuel gas streams. Molecular sieves and activated carbons are some of the sorbents that could be utilized in the PSA process. Volumetric adsorption studies of CO2, N-2, or H-2 on molecular sieve 13X, molecular sieve 4A, and activated carbon were conducted at 25 degreesC up to a pressure of 300 psi (similar to 2x 106 Pa). Preferential. adsorption of CO2 was observed with all three sorbents. The adsorption capacity of CO2 for molecular sieve 13X was higher than that for molecular sieve 4A at all pressures up to 300 psi: At law pressures (<25 psi) the adsorption capacity for CO2 of activated carbon was lower,than that of molecular sieve 13X, but at higher pressures (>25 psi) activated carbon exhibited significantly higher CO2 capacities than were found for molecular sieves. Competitive adsorption of CO2 from gas mixtures also indicated that both molecular sieve 13X and activated carbon can be utilized for separation of CO2 from-gas mixtures. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. RP Siriwardane, RV (reprint author), US DOE, Natl Energy Technol Lab, 3610 Collins Ferry Rd,POB 880, Morgantown, WV 26507 USA. NR 9 TC 476 Z9 495 U1 13 U2 171 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAR-APR PY 2001 VL 15 IS 2 BP 279 EP 284 DI 10.1021/ef000241s PG 6 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 414MC UT WOS:000167669600007 ER PT J AU Oldenburg, CM Pruess, K Benson, SM AF Oldenburg, CM Pruess, K Benson, SM TI Process modeling of CO2 injection into natural gas reservoirs for carbon sequestration and enhanced gas recovery SO ENERGY & FUELS LA English DT Article; Proceedings Paper CT ACS Division of Fuel Chemistry Symposium on CO2 Capture, Utilization, and Sequestration at the National Meeting of the American-Chemical-Society CY AUG 20-24, 2000 CL WASHINGTON, D.C. SP Amer Chem Soc AB Injection of CO2 into depleted natural gas reservoirs offers the potential to sequester carbon while simultaneously enhancing CH4 recovery. Enhanced CH4 recovery can partially offset the costs of CO2 injection. With the goal of analyzing the feasibility of carbon sequestration with enhanced gas recovery (CSEGR), we are investigating the physical processes associated with injecting CO2 into natural gas reservoirs. The properties of natural gas reservoirs and CO2 and CH4 appear to favor CSEGR. To simulate the processes of;CSEGR, a:module for the TOUGH2 reservoir simulator that includes water, brine, CO2, tracer, and CH4 in nonisothermal conditions has been developed. Simulations based on the Rio Vista Gas Field in the Central Valley of California are used to test the feasibility of CSEGR using CO2 separated from flue gas generated by the 680 MW Antioch gas-fired power plant. Model results show that CO2 injection allows additional CH4 to be produced during and after CO2 injection. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Oldenburg, CM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RI Oldenburg, Curtis/L-6219-2013 OI Oldenburg, Curtis/0000-0002-0132-6016 NR 17 TC 105 Z9 110 U1 3 U2 22 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAR-APR PY 2001 VL 15 IS 2 BP 293 EP 298 DI 10.1021/ef000247h PG 6 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 414MC UT WOS:000167669600009 ER PT J AU Blander, M Milne, TA Dayton, DC Backman, R Blake, D Kuhnel, V Linak, W Nordin, A Ljung, A AF Blander, M Milne, TA Dayton, DC Backman, R Blake, D Kuhnel, V Linak, W Nordin, A Ljung, A TI Equilibrium chemistry of biomass combustion: A round-robin set of calculations using available computer programs and databases SO ENERGY & FUELS LA English DT Article ID INORGANIC-CHEMISTRY; THERMODYNAMIC ANALYSIS; WOOD AB Equilibrium calculations of three problems regarding biomass combustion, at various levels of sophistication, were performed at six laboratories using seven combinations of computer programs and databases. The objective was to test the adequacy of the programs and databases for calculating both condensed and gas-phase behavior. The first problem was a simplified calculation for the combustion of a woodlike material with added sulfur to possibly form an ideal molten salt solution of potassium and calcium sulfate. The second and third problems were to simulate aspen wood and wheat straw combustion, respectively, and required a relatively sophisticated database on high-temperature solutions to describe condensed phases. All the participants performed calculations of the gas phases, which were reasonably accurate when their databases were adequate. For problem I, most of the participants were also able to calculate a reasonable set of condensed phases. However, for problems II and III, only four of the participants, using the two most Sophisticated computer programs and databases, had the ability to produce rational results for the condensed phases. This round robin identified two computer programs and their associated databases that could prove useful for calculating the condensed-phase equilibrium chemistry of biomass combustion when coupled with experimental programs and the capability to expand databases as new experimental data become available. Such calculations can greatly enhance our understanding of the total equilibrium chemistry of biomass combustion. C1 QUEST Res, S Holland, IL 60473 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Abo Akad Univ, FIN-20520 Turku, Finland. Camp Dresser & Mc Kee Int CDM, D-44793 Bochum, Germany. US EPA, NRMRL, Res Triangle Pk, NC 27711 USA. Umea Univ, Dept Inorgan Chem, S-90187 Umea, Sweden. RP Dayton, DC (reprint author), QUEST Res, 1004 E 167th Pl, S Holland, IL 60473 USA. RI Nordin, Anders/F-5717-2015 NR 18 TC 11 Z9 11 U1 2 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAR-APR PY 2001 VL 15 IS 2 BP 344 EP 349 DI 10.1021/ef0001181 PG 6 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 414MC UT WOS:000167669600017 ER PT J AU Baltrus, JP Wells, AW Fauth, DJ Diehl, JR White, CM AF Baltrus, JP Wells, AW Fauth, DJ Diehl, JR White, CM TI Characterization of carbon concentrates from coal-combustion fly ash SO ENERGY & FUELS LA English DT Article ID UNBURNED CARBON; PARTICLES; FORMS; SIZE AB A study of carbon concentrates separated by a number of different commercial and laboratory methods from various coal-combustion fly ashes was undertaken to determine what common and unique chemical and physical properties can be expected in such concentrates. The properties were determined using a variety of physical and spectroscopic characterization methods and then were compared among the carbon concentrates and in two cases with the properties of the unprocessed fly ashes. The class F fly ashes originated from a total of seven different utilities burning bituminous coals and underwent one of six different processing methods to produce the carbon concentrates, which contained from 24% to 76% carbon. Three different configurations of triboelectrostatic separators were used to produce the carbon concentrates in addition to two different flotation methods plus a proprietary carbon recovery process. The results showed that unburned carbon concentrates from fly ash have properties similar to most carbon blacks and would be poor replacements for activated carbon in adsorption processes unless they are; activated in a separate step. The untreated carbon may have applications as a substitute for carbon black provided it could be obtained in sufficient purity. The results have implications for those who wish to use carbon concentrates from coal-combustion fly ashes in secondary markets,especially as sorbents and fillers. C1 US DOE, Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. RP Baltrus, JP (reprint author), US DOE, Natl Energy Technol Lab, POB 10940, Pittsburgh, PA 15236 USA. NR 41 TC 38 Z9 39 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAR-APR PY 2001 VL 15 IS 2 BP 455 EP 462 DI 10.1021/ef000201o PG 8 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 414MC UT WOS:000167669600032 ER PT J AU Stern, LA Circone, S Kirby, SH Durham, WB AF Stern, LA Circone, S Kirby, SH Durham, WB TI Preservation of methane hydrate at 1 Atm SO ENERGY & FUELS LA English DT Article ID GAS HYDRATE; DISSOCIATION; TEMPERATURES; ICE C1 US Geol Survey, Menlo Park, CA 94025 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Stern, LA (reprint author), US Geol Survey, 345 Middlefield Rd,MS 977, Menlo Park, CA 94025 USA. NR 15 TC 18 Z9 19 U1 1 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAR-APR PY 2001 VL 15 IS 2 BP 499 EP 501 DI 10.1021/ef000277k PG 3 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 414MC UT WOS:000167669600038 ER PT J AU Roberts, PM Sharma, A Uddameri, V Monagle, M Dale, DE Steck, LK AF Roberts, PM Sharma, A Uddameri, V Monagle, M Dale, DE Steck, LK TI Enhanced DNAPL transport in a sand core during dynamic stress stimulation SO ENVIRONMENTAL ENGINEERING SCIENCE LA English DT Article DE groundwater remediation; DNAPL mobilization and transport; stress-wave stimulation ID ULTRASONIC REMOVAL; POROUS-MEDIA; REMEDIATION; GANGLIA; DAMAGE AB Extraction of dense, nonaqueous-phase liquid (DNAPL) contaminants trapped in groundwater aquifers is a major problem in environmental remediation because existing field techniques, such as pump and treat, have limited effectiveness. We present new laboratory experimental evidence that low-frequency (100 Hz or less) stress waves could increase the mobility and transport of DNAPL by an order of magnitude or more during pump and treat. This unproven technology could decrease the time and cost of groundwater remediation efforts and reduce the final amount of contaminant trapped in an aquifer. A sand core was confined in a specialized flow apparatus and contaminated with a small amount of trichloroethylene (TCE). Steady-state water flow was then initiated through the core, and affluent TCE concentrations were measured using gas chromatography (GC). At various stages of water flow, axial stress cycling at 25-100 Hz was applied by mechanical coupling of a magnetostrictive actuator to the sand core's outlet face. During most of the stimulated runs pure-phase TCE droplets were produced in the effluent and the effective TCE concentration increased by as much as a factor of 20. Numerous flow runs were performed to investigate the effects of stimulation frequency, amplitude, and duration, as well as water flow rate and background effluent TCE concentration. Calibrated accelerometer and pore pressure measurements allowed determination of the stimulation threshold parameters required to achieve enhanced TCE production. The physical mechanisms responsible for the observed phenomenon are not fully understood. Further research is required before this promising new technology can be applied reliably to contaminated groundwater aquifers. C1 Univ Calif Los Alamos Natl Lab, Grp EES 4, Los Alamos, NM 87545 USA. Univ Maine, Orono, ME 04469 USA. Adv Ind Chem Corp, Albuquerque, NM 87114 USA. RP Roberts, PM (reprint author), Univ Calif Los Alamos Natl Lab, Grp EES 4, Mail Stop D443, Los Alamos, NM 87545 USA. NR 22 TC 33 Z9 34 U1 2 U2 7 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1092-8758 J9 ENVIRON ENG SCI JI Environ. Eng. Sci. PD MAR-APR PY 2001 VL 18 IS 2 BP 67 EP 79 DI 10.1089/10928750151132230 PG 13 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 424NR UT WOS:000168238800001 ER PT J AU Fernando, HJS Lee, SM Anderson, J Princevac, M Pardyjak, E Grossman-Clarke, S AF Fernando, H. J. S. Lee, S. M. Anderson, J. Princevac, M. Pardyjak, E. Grossman-Clarke, S. TI Urban Fluid Mechanics: Air Circulation and Contaminant Dispersion in Cities SO ENVIRONMENTAL FLUID MECHANICS LA English DT Article AB Recently, many urban areas of the world have experienced rapid growth of population and industrial activity raising concerns of environmental deterioration. To meet challenges associated with such rapid urbanization, it has become necessary to implement wise strategies for environmental management and planning, addressing the exclusive demands of urban zones for maintaining environmental sustainability and functioning with minimum disruption. These strategies and related public policy must be based on state-of-the-science tools for environmental forecasting, in particular, on mathematical models that accurately incorporate physical, biological, chemical and geological processes at work on urban scales. Central to such models are the mechanics of environmental fluids (air and water) and their transport and transformation characteristics. Although much progress has been made on understanding environmental flow phenomena, a myriad of issues akin to urban flow, the transport phenomena, air and water quality and health issues (epidemiology) remain to be understood and quantified. We propose to initiate a new focus area - Urban Fluid Mechanics (UFM) - tailored to research on such issues. For optimal societal impact, UFM must delve into fundamental and applied fluid flow problems of immediate utility for the development of urban public policy and environmental regulations. Such efforts often entail the use of 'whole' systems approach to environmental studies, requiring careful synthesis between crosscutting areas. In this paper, a few topics in the realm of UFM are presented, the theme being the flow and air quality in urban areas. Topics such as the scales of flow, the atmospheric boundary layer, pollutants and their transport and modeling of flow and air quality are briefly reviewed, discussed and exemplified using case studies. Identification of important flow-related issues, rigorous multidisciplinary approaches to address them and articulation of results in the context of socio-political cause calebre will be the challenges faced by UFM. C1 [Fernando, H. J. S.; Lee, S. M.; Anderson, J.; Princevac, M.; Pardyjak, E.; Grossman-Clarke, S.] Arizona State Univ, Dept Mech & Aerosp Engn, Environm Fluid Dynam Program, Tempe, AZ 85287 USA. [Pardyjak, E.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Fernando, HJS (reprint author), Arizona State Univ, Dept Mech & Aerosp Engn, Environm Fluid Dynam Program, Tempe, AZ 85287 USA. FU Office of the Vice Provost for Research (VPR); Center for Environmental Studies; Environmental Geochemistry and Biogeochemistry (EGB) Initiative of the NSF; Urban Initiative of the NSF; NSF; Arizona Department of Environmental Quality (ADEQ); Arizona Department of Transportation (ADOT); Army Research Office (Geosciences); Department of Energy (Environmental Meteorology); USEPA via the Southwest Center for Environmental Research and Policy (SCERP) FX The urban fluid mechanics research at Arizona State University (ASU) was launched in response to a University Initiative on Urban Environments, conceived and munificently supported by the Office of the Vice Provost for Research (VPR). We wish to thank VPR Jonathan Fink, Provost Milton Glick, Vice Provost Kathleen Church and Dean Peter Crouch for their encouragement and support, without which the work reported herein could not have been realized. Professors Don Boyer, Gregory Raupp and Neil Berman were instrumental in setting up the infrastructure for multidisciplinary work and numerous colleagues at ASU and visiting scientists (the list of names is too long to mention, for which we wish to apologize) are helping with our on-going work. The US National Science Foundation (NSF) has established one of its two urban Long-Term Ecological Research (LTER) sites at Arizona State University under the auspices of the Center for Environmental Studies, which acts as a valuable information resource for urban environmental studies. Since 1998, urban fluid mechanics research at ASU has been funded by the Environmental Geochemistry and Biogeochemistry (EGB) Initiative, Urban Initiative and the unsolicited grant programs of the NSF, the Arizona Department of Environmental Quality (ADEQ), Arizona Department of Transportation (ADOT), the Army Research Office (Geosciences), the Department of Energy (Environmental Meteorology) and the USEPA via the Southwest Center for Environmental Research and Policy (SCERP). Peter Hyde of ADEQ spent endless hours in providing technical support for air quality modeling, Estomih Kombe of ADOT provided useful technical information on Arizona highways, and Bruce Kimball of the U. S. Water Conservatory Laboratory provided Figure 4 of the paper. Professor Jong-Jin Baik kindly provided the CFD code. Invaluable help received from our ASU colleagues, Jennifer McCulley, Gabrielle Stidham, Dana Perry, Frank Yu and Destry Lucas during the preparation of this manuscript and data analysis is greatly appreciated. Editor of the Journal of Environmental Fluid Mechanics, Professor Benoit Cushman-Roisin, provided valuable guidance NR 230 TC 90 Z9 94 U1 4 U2 24 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1567-7419 EI 1573-1510 J9 ENVIRON FLUID MECH JI Environ. Fluid Mech. PD MAR PY 2001 VL 1 IS 1 BP 107 EP 164 DI 10.1023/A:1011504001479 PG 58 WC Environmental Sciences; Mechanics; Meteorology & Atmospheric Sciences; Oceanography; Water Resources SC Environmental Sciences & Ecology; Mechanics; Meteorology & Atmospheric Sciences; Oceanography; Water Resources GA V26MB UT WOS:000208548600006 ER PT J AU Hieresen, DL Anastas, P Ware, S Kirchhoff, M AF Hieresen, DL Anastas, P Ware, S Kirchhoff, M TI Green chemistry progress & challenges SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID LIGAND-EXCHANGE C1 Univ Calif Los Alamos Natl Lab, Green Chem Inst, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Environm Management Program, Los Alamos, NM 87545 USA. Amer Chem Soc, Div Educ & Int Act, Washington, DC 20036 USA. Trinity Coll, Dept Chem, Washington, DC USA. RP Hieresen, DL (reprint author), Univ Calif Los Alamos Natl Lab, Green Chem Inst, Los Alamos, NM 87545 USA. RI Anastas, Paul/L-3258-2013 OI Anastas, Paul/0000-0003-4777-5172 NR 12 TC 1 Z9 1 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD MAR 1 PY 2001 VL 35 IS 5 BP 114A EP 119A PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 407XQ UT WOS:000167296400021 ER PT J AU Zhang, H Lindberg, SE AF Zhang, H Lindberg, SE TI Sunlight and iron(III)-induced photochemical production of dissolved gaseous mercury in freshwater SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID NUTRIENT REMOVAL PROJECT; NATURAL-WATERS; ATMOSPHERIC MERCURY; FLORIDA EVERGLADES; AIR/WATER EXCHANGE; ELEMENTAL MERCURY; AQUEOUS REACTIONS; VOLATILE MERCURY; TEMPERATE LAKES; SURFACE WATERS AB Mechanistic understanding of sunlight-induced natural processes for production of dissolved gaseous mercury (DGM) in freshwaters has remained limited, and few direct field tests of the mechanistic hypotheses are available. We exposed ferric iron salt-spiked fresh surface lake water (Whitefish Bay, Lake Superior, MI) in Teflon bottles and pond water (Oak Ridge, TN) in quartz bottles to sunlight in the field to infer if sunlight and Fe(III)-induced photochemical production of DGM could mechanistically contribute partly to natural photochemical production of DGM in freshwaters. We found that exposure of freshwater spiked with fresh Fe(III) (similar to5 or 10 muM) to sunlight led to repeatable, significantly larger increases in DGM production (e.g., 380% in 1 h, 420% in 2 h, and 470% in 4 h for Whitefish Bay water) than exposure without the spike (e.g., 200% in 6 h). DGM increased with increasing exposure time and then often appeared to approach a steady slate in the tests. Higher Fe(III) spike levels resulted in the same, or even less, DGM production. Storage of the water with or without Fe(III) spike in the dark after sunlight exposure led to significant, apparently first-order, decreases in DGM. These phenomena were hypothetically attributed to sunlight-induced photochemical production of highly reducing organic free radicals through photolysis of Fe(III)-organic acid coordination compounds and subsequent reduction of Hg(II) to Hg(O) by the organic free radicals; the reduction was also accompanied by dark oxidation of Hg(O) by photochemically originated oxidants (e.g.,(OH)-O-.). This study suggests that sunlight and Fe(III)-induced photochemical reduction of Hg(II)could be one of the mechanisms responsible far natural photochemical production of DGM in freshwaters and that Fe species may be influential in mediating Hg chemodynamics and its subsequent toxicity in aquatic ecosystems. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Oak Ridge Associated Univ, Oak Ridge, TN 37831 USA. RP Zhang, H (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 44 TC 131 Z9 137 U1 2 U2 28 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD MAR 1 PY 2001 VL 35 IS 5 BP 928 EP 935 DI 10.1021/es001521p PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 407XQ UT WOS:000167296400038 PM 11351537 ER PT J AU Heinemeyer, S Hollik, W Rosiek, J Weiglein, G AF Heinemeyer, S Hollik, W Rosiek, J Weiglein, G TI Neutral MSSM Higgs-boson production at e(+)e(-) colliders in the Feynman-diagrammatic approach SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID SUPERSYMMETRIC STANDARD MODEL; RADIATIVE-CORRECTIONS; QCD CORRECTIONS; 2-LOOP LEVEL; UPPER LIMIT; MASS; LEP; COLLISIONS; RENORMALIZATION; PHENOMENOLOGY AB We calculate the cross sections for the neutral Higgs-boson production at e(+)e(-) colliders in the Minimal Supersymmetric Standard Model (MSSM) using the Feynman-diagrammatic approach and the on-shell renormalization scheme. We incorporate the Higgs-boson propagator corrections, evaluated up to two-loop order, into the prediction of the cross sections for the Higgs-boson production mechanism e(+)e(-) --> hZ, hA. The propagator corrections consist of the full one-loop contribution, including the effects of non-vanishing external momentum, and at the two-loop level of the dominant corrections of O(alpha alpha (s)) and further sub-dominant contributions. The results are supplemented with the complete set of one-loop vertex and box corrections. The effects of the two-loop propagator corrections are investigated in detail. We briefly discuss also the effect of the box contributions for high roots. We compare our results with the case where only the corrections to the effective mixing angle, evaluated within the renormalization-group-improved one-loop Effective Potential approach, are taken into account. Wie find agreement better than 10% for LEP2 energies and deviations larger than 20% for roots = 500 GeV. C1 Brookhaven Natl Lab, Dept Phys, HET, Upton, NY 11973 USA. Univ Karlsruhe, Inst Theoret Phys, D-76128 Karlsruhe, Germany. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Univ Warsaw, Inst Theoret Phys, PL-00681 Warsaw, Poland. CERN, Div TH, CH-1211 Geneva, Switzerland. RP Heinemeyer, S (reprint author), Brookhaven Natl Lab, Dept Phys, HET, Upton, NY 11973 USA. OI Rosiek, Janusz/0000-0002-1653-1274 NR 49 TC 30 Z9 30 U1 0 U2 1 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6044 J9 EUR PHYS J C JI Eur. Phys. J. C PD MAR PY 2001 VL 19 IS 3 BP 535 EP 546 DI 10.1007/s100520100631 PG 12 WC Physics, Particles & Fields SC Physics GA 439HV UT WOS:000169106900014 ER PT J AU Lal, J Abernathy, D Auvray, L Diat, O Grubel, G AF Lal, J Abernathy, D Auvray, L Diat, O Grubel, G TI Dynamics and correlations in magnetic colloidal systems studied by X-ray photon correlation spectroscopy SO EUROPEAN PHYSICAL JOURNAL E LA English DT Article ID SUSPENSIONS; SCATTERING; FERROFLUID; ESRF AB We have studied the static and dynamic behaviour of magnetic colloidal systems (ferrofluids) by Small-Angle X-ray Scattering (SAXS) and X-ray Photon Correlation Spectroscopy (XPCS). The main features of the novel XPCS technique will be illustrated by data taken on a model system, colloidal silica spheres. We will then present the results obtained on an optically opaque suspension of magnetic colloids (maghemite) in the wave vector range from 10(-3) to 10(-2) A(-1). Translational diffusion in zero field and anisotropic diffusion under external magnetic fields will be discussed. C1 European Synchrotron Radiat Facil, F-38043 Grenoble, France. CEA Saclay, Leon Brillouin Lab, F-91191 Gif Sur Yvette, France. RP Lal, J (reprint author), Argonne Natl Lab, IPNS, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Abernathy, Douglas/A-3038-2012; Auvray, Loic/J-7577-2012; diat, olivier/B-5985-2016 OI Abernathy, Douglas/0000-0002-3533-003X; Auvray, Loic/0000-0003-1736-5578; diat, olivier/0000-0003-3011-8168 NR 34 TC 44 Z9 45 U1 3 U2 9 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1292-8941 J9 EUR PHYS J E JI Eur. Phys. J. E PD MAR PY 2001 VL 4 IS 3 BP 263 EP 271 DI 10.1007/s101890170108 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Applied; Polymer Science SC Chemistry; Materials Science; Physics; Polymer Science GA 412AZ UT WOS:000167533000002 ER PT J AU Hart, WE AF Hart, WE TI A convergence analysis of unconstrained and bound constrained evolutionary pattern search SO EVOLUTIONARY COMPUTATION LA English DT Article DE evolutionary pattern search; local convergence; bound constraints; parameter adaptation ID ALGORITHMS; OPTIMIZATION; MINIMIZATION AB We present and analyze a class of evolutionary algorithms for unconstrained and bound constrained optimization on R-n evolutionary pattern search algorithms (EPSAs). EPSAs adaptively modify the step size of the mutation operator in response to the success of previous optimization steps. The design of EPSAs is inspired by recent analyses of pattern search methods. We show that EPSAs can be cast as stochastic pattern search methods, and we use this observation to prove that EPSAs have a probabilistic, weak stationary point convergence theory. This convergence theory is distinguished by the fact that the analysis does not approximate the stochastic process of EPSAs, and hence it exactly characterizes their convergence properties. C1 Sandia Natl Labs, Optimizat Uncertainty Estimat Dept, Albuquerque, NM 87185 USA. RP Hart, WE (reprint author), Sandia Natl Labs, Optimizat Uncertainty Estimat Dept, POB 5800,MS 1110, Albuquerque, NM 87185 USA. NR 36 TC 18 Z9 19 U1 0 U2 2 PU M I T PRESS PI CAMBRIDGE PA FIVE CAMBRIDGE CENTER, CAMBRIDGE, MA 02142 USA SN 1063-6560 J9 EVOL COMPUT JI Evol. Comput. PD SPR PY 2001 VL 9 IS 1 BP 1 EP 23 DI 10.1162/10636560151075095 PG 23 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA 493VT UT WOS:000172244700002 PM 11290281 ER PT J AU Frew, DJ Forrestal, MJ Chen, W AF Frew, DJ Forrestal, MJ Chen, W TI A split Hopkinson pressure bar technique to determine compressive stress-strain data for rock materials SO EXPERIMENTAL MECHANICS LA English DT Article DE Hopkinson bar; pulse shaping; rock materials; high strain rate ID RATES AB This paper presents a split Hopkinson pressure bar technique to obtain compressive stress-strain data for rock materials. This technique modifies the conventional split Hopkinson bar apparatus by placing a thin copper disk on the impact surface of the incident bar. When the striker bar impacts the copper disk, a nondispersive ramp pulse propagates in the incident bar and produces a nearly constant strain rate in a rock sample. Data from experiments with limestone show that the samples are in dynamic stress equilibrium and have constant strain rates over most of the test durations. In addition, the ramp pulse durations can be controlled such that samples are unloaded just prior to failure. Thus, intact samples that experience strains beyond the elastic region and postpeak stresses can be retrieved for microstructural evaluations. The paper also presents analytical models that predict the time durations for sample equilibrium and constant strain rate. Model predictions are in good agreement with measurements. C1 USA, Waterways Expt Stn, Engineer Res & Dev Ctr, Struct Lab, Vicksburg, MS 39180 USA. Sandia Natl Labs, Tech Staff, Albuquerque, NM 87185 USA. Univ Arizona, Dept Aerosp & Mech Engn, Tucson, AZ 85721 USA. RP Frew, DJ (reprint author), USA, Waterways Expt Stn, Engineer Res & Dev Ctr, Struct Lab, Vicksburg, MS 39180 USA. NR 19 TC 133 Z9 158 U1 2 U2 29 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0014-4851 EI 1741-2765 J9 EXP MECH JI Exp. Mech. PD MAR PY 2001 VL 41 IS 1 BP 40 EP 46 DI 10.1007/BF02323102 PG 7 WC Materials Science, Multidisciplinary; Mechanics; Materials Science, Characterization & Testing SC Materials Science; Mechanics GA 403EE UT WOS:000167029000005 ER PT J AU Garcia, J AF Garcia, J TI The need for computational model validation SO EXPERIMENTAL TECHNIQUES LA English DT Article RP Garcia, J (reprint author), US DOE, Washington, DC USA. NR 8 TC 4 Z9 4 U1 0 U2 2 PU SOC EXPERIMENTAL MECHANICS PI BETHEL PA 7 SCHOOL STREET, BETHEL, CT 06801 USA SN 0732-8818 J9 EXP TECHNIQUES JI Exp. Tech. PD MAR-APR PY 2001 VL 25 IS 2 BP 31 EP 33 DI 10.1111/j.1747-1567.2001.tb00015.x PG 3 WC Engineering, Mechanical; Mechanics; Materials Science, Characterization & Testing SC Engineering; Mechanics; Materials Science GA 422BW UT WOS:000168098900012 ER PT J AU Stewart, SD Graham, LC Gaylor, MJ Vanderberg, LA AF Stewart, SD Graham, LC Gaylor, MJ Vanderberg, LA TI Combining exclusion techniques and larval death-rate analyses to evaluate mortality factors of Spodoptera exigua (Lepidoptera : Noctuidae) in cotton SO FLORIDA ENTOMOLOGIST LA English DT Article DE contemporaneous mortality; beet armyworm; predation; Cotesia ID BEET ARMYWORM LEPIDOPTERA; NATURAL ENEMIES; FLIGHT PHENOLOGY; CALIFORNIA; INSECTICIDES; PARASITOIDS; PREDATORS; HOMOPTERA; APHIDIDAE; DENSITY AB By combining pesticide exclusion and cage exclusion techniques, the efficacy of natural enemies in reducing populations of Spodoptera exigua (Hubner), the beet armyworm, larvae was effectively demonstrated. Larval collections added information about parasitism and disease, and when combined with data from insecticide treatments, demonstrated that differences in S. exigua population densities usually were due to the action of predators. Deathrate analyses demonstrated that much mortality due to parasitism was contemporaneous with death from predation. When predator populations were not reduced by insecticides, most indispensable natural mortality was due to predation. When predators were eliminated, and S. exigua populations reached outbreak levels, most larvae died from disease in 1989 and from parasitism in 1990. C1 Mississippi State Univ, Dept Entomol & Plant Pathol, Mississippi State, MS 39762 USA. Auburn Univ, Alabama Agr Expt Stn, Dept Entomol, Auburn, AL 36849 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Stewart, SD (reprint author), Mississippi State Univ, Dept Entomol & Plant Pathol, Mississippi State, MS 39762 USA. NR 35 TC 6 Z9 7 U1 0 U2 7 PU FLORIDA ENTOMOLOGICAL SOC PI LUTZ PA 16125 E LAKE BURRELL DR, LUTZ, FL 33548 USA SN 0015-4040 J9 FLA ENTOMOL JI Fla. Entomol. PD MAR PY 2001 VL 84 IS 1 BP 7 EP 22 DI 10.2307/3496657 PG 16 WC Entomology SC Entomology GA 422CV UT WOS:000168101100002 ER PT J AU Panofsky, WKH AF Panofsky, WKH TI Going nuclear-free SO FOREIGN AFFAIRS LA English DT Letter C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA. RP Panofsky, WKH (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU COUNC FOREIGN RELAT INC PI NEW YORK PA 58 E 68TH ST, NEW YORK, NY 10021 USA SN 0015-7120 J9 FOREIGN AFF JI Foreign Aff. PD MAR-APR PY 2001 VL 80 IS 2 BP 193 EP 194 DI 10.2307/20050136 PG 2 WC International Relations SC International Relations GA 405DJ UT WOS:000167142300020 ER PT J AU Riemenschneider, DE Berguson, WE Dickmann, DI Hall, RB Isebrands, JG Mohn, CA Stanosz, GR Tuskan, GA AF Riemenschneider, DE Berguson, WE Dickmann, DI Hall, RB Isebrands, JG Mohn, CA Stanosz, GR Tuskan, GA TI Poplar breeding and testing strategies in the north-central US: Demonstration of potential yield and consideration of future research needs SO FORESTRY CHRONICLE LA English DT Article; Proceedings Paper CT 21st Meeting of the International-Popular-Commission CY SEP 24-28, 2000 CL VANCOUVER, WASHINGTON SP Int Popular Comm DE Populus; biomass; multi-trait selection; genotype; genotype x environment interaction ID ENERGY AB We present results from a Populus Regional Testing Program that has been conducted in Minnesota, Iowa, Wisconsin, and Michigan over the past six years. Our objectives have been to: 1)identify highly productive, disease resistant intra- and inter-specific clonal selections and 2) understand patterns of genotype x environment interactions within the region that would, logically, govern commercial deployment of new clones. Clones were developed by breeding and selection programs at the University of Illinois, Iowa State University, University of Minnesota, and the USDA Forest Service for experiments established in 1995. We report results of analyses of variance and principal component analyses of tree diameters and estimated above-ground biomass that demonstrate significant genotype main effects and significant genotype x environment interactions. Maximum mean annual above-ground biomass increments have surpassed 16 Mg ha(-1) y(-1), exceeding previously reported yields of poplars grown under similar conditions in the north-central U.S. We also discuss the breeding and selection of poplars in general with specific attention to regional research needs. C1 US Forest Serv, USDA, N Cent Res Stn, Forestry Sci Lab, Rhinelander, WI 54501 USA. Univ Minnesota, Nat Resources Res Inst, Duluth, MN 55811 USA. Michigan State Univ, E Lansing, MI 48824 USA. Iowa State Univ, Ames, IA USA. Univ Minnesota, St Paul, MN 55108 USA. Univ Wisconsin, Madison, WI USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Riemenschneider, DE (reprint author), US Forest Serv, USDA, N Cent Res Stn, Forestry Sci Lab, 5985 Highway K, Rhinelander, WI 54501 USA. RI Tuskan, Gerald/A-6225-2011 OI Tuskan, Gerald/0000-0003-0106-1289 NR 17 TC 62 Z9 67 U1 3 U2 11 PU CANADIAN INST FORESTRY PI OTTAWA PA 151 SLATER ST, STE 606, OTTAWA, ONTARIO K1P 5H3, CANADA SN 0015-7546 J9 FOREST CHRON JI For. Chron. PD MAR-APR PY 2001 VL 77 IS 2 BP 245 EP 253 PG 9 WC Forestry SC Forestry GA 436LE UT WOS:000168936700009 ER PT J AU Tuskan, GA Walsh, ME AF Tuskan, GA Walsh, ME TI Short-rotation woody crop systems, atmospheric carbon dioxide and carbon management: A US case study SO FORESTRY CHRONICLE LA English DT Article; Proceedings Paper CT 21st Meeting of the International-Popular-Commission CY SEP 24-28, 2000 CL VANCOUVER, WASHINGTON SP Int Popular Comm DE Populus; biomass; carbon sequestration; carbon displacement; Kyoto protocol; CO2 ID LAND-USE CHANGE; UNITED-STATES; TERRESTRIAL CARBON; FORESTS; ENERGY; SEQUESTRATION; SINKS; CO2 AB Atmospheric concentrations of carbon dioxide (CO2) are increasing along with global use of fossil fuels and worldwide rates of deforestation. These trends have led international panels and organizations to devise carbon management strategies in an effort to curb increases in CO2. The goal of this paper is to explore the potential role of short-rotation woody crops (SRWC) in the U.S. as one option in a carbon-managed future economy. On a scale of 40 x 10(6) ha, and at an average productivity rate of 21 Mg oven-dry biomass ha(-1) yr(-1) SRWC systems could account for an average of 0.30 Pg of C yr(-1) when prorated over the 50-year deployment life of a typical SRWC system. Most of the accounted carbon (76%) would come from fossil fuel displacement as opposed to direct carbon sequestration. The proportion of accounted carbon associated with fossil fuel displacement increases with longer time frames due to the relatively rapid saturation of the carbon sequestration pool. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37830 USA. Oak Ridge Natl Lab, Energy Res Div, Oak Ridge, TN 37830 USA. RP Tuskan, GA (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008,MS-6422, Oak Ridge, TN 37830 USA. RI Tuskan, Gerald/A-6225-2011 OI Tuskan, Gerald/0000-0003-0106-1289 NR 30 TC 54 Z9 56 U1 1 U2 9 PU CANADIAN INST FORESTRY PI OTTAWA PA 151 SLATER ST, STE 606, OTTAWA, ONTARIO K1P 5H3, CANADA SN 0015-7546 J9 FOREST CHRON JI For. Chron. PD MAR-APR PY 2001 VL 77 IS 2 BP 259 EP 264 PG 6 WC Forestry SC Forestry GA 436LE UT WOS:000168936700011 ER PT J AU Longhurst, G AF Longhurst, G TI 14th Topical Meeting on the Technology of Fusion Energy - Preface SO FUSION TECHNOLOGY LA English DT Editorial Material C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Longhurst, G (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP XV EP XV PN 2 PG 1 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100002 ER PT J AU Sheffield, J Williams, KA Reid, RL Hadley, S AF Sheffield, J Williams, KA Reid, RL Hadley, S TI An assessment of the economics of future electric power generation options and the implications for fusion SO FUSION TECHNOLOGY LA English DT Article ID DESIGN AB This study examines the potential range of electric power costs for some major alternatives to fusion electric power generation when it is ultimately deployed in the middle of the 21st century and, thus, offers a perspective on the cost levels that fusion must achieve to be competitive. The alternative technologies include coal burning, coal gasification, natural gas, nuclear fission, and renewable energy. The cost of electricity (COE)from the alternatives to fusion should be in a 30 to 53 mills/ kW.h (1999 dollars) range if carbon sequestration is not needed, 30 to 61 mills/kW.h if sequestration is required, or as high as 83 mills/kW.h for the worst-case scenario for cost uncertainty. The reference COE range for fusion was estimated at 65 to 102 mills/kW.h for 1- to 1.3-GW(electric) scale power plants, based on the tokamak concept. Tokamak fusion costs will have to be reduced and/or cost-effective alternative nontokamak concepts devised before fusion will be competitive with the alternatives for the future production of electricity. Fortunately, there are routes to achieve this goal. Recent results from fusion experiments and developments in technology and engineering solutions indicate that lower cost fusion power plants are possible at the 1-GW(electric) level. Another general route for fusion to reduce costs is to go to large plant sizes [multigigawatts (electric)]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Sheffield, J (reprint author), 19 Windhaven Lane, Oak Ridge, TN 37830 USA. RI Hadley, Stanton/O-1465-2015 OI Hadley, Stanton/0000-0002-6514-8802 NR 39 TC 1 Z9 1 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 228 EP 248 PG 21 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 401MN UT WOS:000166931400008 ER PT J AU Petersen, PI AF Petersen, PI CA DIII-D Team TI Recent findings in DIII-D relative to advanced tokamak modes and their implications for fusion energy SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UT SP Amer Nucl Soc ID IMPROVED CONFINEMENT; MAGNETIC SHEAR; POWER-PLANT; HIGH-BETA; PLASMA AB An advanced tokamak is characterized by increased confinement, stability and steady state operation. The increased confinement and stability are obtained through modifications to the shape and profiles of the plasma and through stability feedback control. These modifications have to be self-consistent. The increased confinement makes it possible to make smaller and thereby lower cost reactors for the same power output as compared to conventional tokamaks. Four potential modes for advanced tokamaks are currently being studied on DIII-D: radiative improved mode, high internal inductance ei mode, negative central shear (NCS) mode, and quiescent double barrier (QDB) mode. High-density plasma are important for reactors and recent experiments in DIII-D have shown that it is possible to operate substantially above the Greenwald limit. Control of the internal transport barriers that are responsible for the increased confinement have been improved in counter injected neutral beam plasmas. One of the limiting instabilities for the performance of high bootstrap fraction negative central shear plasmas is the resistive wall mode. These modes have to a certain degree been suppressed in DIII-D by using the six-section correction coil. With a newly installed upper inner divertor in DIII-D it has been possible to obtain improved density and impurity control. An upgrade of the electron cyclotron system is being done on DIII-D. Three 1 MW gyrotrons are being added. This system has been used to completely suppress the neoclassical tearing mode by applying electron cyclotron current drive at definite positions and in very localized areas. Finally, the implication of the recent findings for fusion reactors will be discussed. C1 Gen Atom Co, San Diego, CA 92186 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Texas, Austin, TX 78712 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. Sandia Natl Labs, Livermore, CA 94550 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Cornell Univ, New York, NY 10021 USA. Univ Calif San Diego, San Diego, CA 92103 USA. FARTECH, San Diego, CA USA. Chalmers Univ, Gotteborg, Sweden. ORISE, Oak Ridge, TN USA. Univ Wisconsin, Madison, WI 53705 USA. Univ Calif Irvine, Irvine, CA 92697 USA. ASIPP, Hefei, Peoples R China. Univ Wales Coll Cardiff, Cardiff CF1 3NS, S Glam, Wales. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Maryland, College Pk, MD 20742 USA. Palomar Coll, San Marcos, CA USA. IPP, Garching, Germany. Keldysh Inst, Moscow, Russia. CEA, Assoc EURATOM, Cadarache, France. UKAEA, Culham Lab, Abingdon OX14 3DB, Oxon, England. Comp X, Del Mar, CA USA. Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. Hampton Univ, Hampton, VA 23668 USA. TRINITI, Troitsk, Russia. Lehigh Univ, Bethlehem, PA 18015 USA. Georgia Tech, Atlanta, GA USA. Ecoloe Royole Mil Acad, Assoc EURATOM, Brussels, Belgium. MIT, Cambridge, MA 02139 USA. Univ Toronto, Toronto, ON, Canada. Forschungszentrum Julich, Assoc EURATOM, Julich, Germany. Univ Pahwa, Padua, Italy. RP Petersen, PI (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 22 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 305 EP 314 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100005 ER PT J AU Hogan, WJ Moses, E Warner, B Sorem, M Soures, J Hands, J AF Hogan, WJ Moses, E Warner, B Sorem, M Soures, J Hands, J TI The National Ignition Facility project: An update SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB The National Ignition Facility (NIF) consists of 192 forty-centimeter-square laser beams and a 10-m-diameter target chamber. Physical construction began in 1997. The Laser and Target Area Building and the Optics Assembly Building were the first major construction activities, and despite several unforeseen obstacles, the buildings are now 92% complete and have been done on time and within cost. Prototype component development and testing has proceeded in parallel. Optics vendors have installed full-scale production lines and have done prototype production runs. The assembly and integration of the beampath infrastructure has been reconsidered and a new approach has been developed. This paper will discuss the status of the NIF project and the plans for completion. It will also include summary information on Laser MegaJoule (LMJ) provided by M. Andre, LMJ Project Director. C1 LLNL, Livermore, CA USA. LANL, Los Alamos, NM USA. Univ Rochester, Rochester, NY USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hogan, WJ (reprint author), LLNL, Livermore, CA USA. NR 8 TC 1 Z9 1 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 329 EP 335 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100008 ER PT J AU Meade, DM AF Meade, DM TI Fusion Ignition Research Experiment (FIRE) SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Experiments are needed to test and extend present understanding of confinement, macroscopic stability, alpha-driven instabilities, and particle/power exhaust in plasmas dominated by alpha heating. A. design study of a Fusion Ignition Research Experiment(FIRE) is underway to assess near term opportunities for producing and studying fusion dominated plasmas in the laboratory. The emphasis is on understanding the behavior of fusion plasmas dominated by alpha heating (Q greater than or equal to 5) that are sustained for a duration comparable to the characteristic plasma time scales (greater than or equal to 20 tau (E) and similar to 1.5 tau (skin), where tau (skin) is the time for the plasma current profile to redistribute at fixed current). These requirements can be satisfied with BeCu/OFHC toroidal field coils and OFHC poloidal coils that are pre-cooled to 77 degreesK prior to the pulse. The plasma facing components will have tungsten divertor plates and Be first wall tiles. No graphite is allowed inside the vacuum vessel due to tritium retention issues. The mission of FIRE is to attain, explore, understand and optimize alpha-dominated plasmas to provide knowledge for the design of attractive magnetic fusion energy systems. The programmatic strategy is to access the alpha-heating-dominated regime with confidence using the present advanced tokamak data base (e.g., Elmy-H-mode, less than or equal to 0.75 Greenwald density) while maintaining the flexibility for accessing and exploring other advanced tokamak modes (e. g., reversed shear, pellet enhanced performance) at lower magnetic fields and fusion power for longer durations in later stages of the experimental program. A major constraint. is to develop a design concept that could meet these physics objectives with a construction cost in the range of $1B. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Meade, DM (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 14 TC 12 Z9 12 U1 1 U2 2 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 336 EP 342 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100009 ER PT J AU Tillack, MS Najmabadi, F El-Guebaly, LA Peterson, RR Goodin, DT Schultz, KR Meier, WR Perkins, J Petti, DA Sethian, JD Waganer, LM AF Tillack, MS Najmabadi, F El-Guebaly, LA Peterson, RR Goodin, DT Schultz, KR Meier, WR Perkins, J Petti, DA Sethian, JD Waganer, LM CA ARIES Team TI ARIES inertial fusion chamber assessment SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID DESIGN; ENERGY AB A critical assessment of the feasibility of IFE chambers has been initiated. This work seeks to define design windows and explore in detail the tradeoffs for various chamber concepts. The work is performed in an integrated and self-consistent manner by including all key elements of IFE chambers, including target physics, target fabrication, injection and tracking, final optics interface and protection, chamber engineering, safety and environment. Chamber concepts are being considered in a sequential fashion; initial studies reported here have concentrated on dry wall options. The goals and approach of the program are described and preliminary results reported. C1 Univ Calif San Diego, Energy Res Ctr, La Jolla, CA 92093 USA. Univ Wisconsin, Fus Technol Inst, Madison, WI 53706 USA. Gen Atom Co, San Diego, CA 92186 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. USN, Res Lab, Washington, DC 20375 USA. Boeing Co, St Louis, MO 63166 USA. RP Tillack, MS (reprint author), Univ Calif San Diego, Energy Res Ctr, La Jolla, CA 92093 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 343 EP 349 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100010 ER PT J AU Taylor, NP Cheng, ET Petti, DA Zucchetti, M AF Taylor, NP Cheng, ET Petti, DA Zucchetti, M TI Overview of international waste management activities in fusion SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UT SP Amer Nucl Soc ID ACTIVATION; SAFETY AB The minimization of active waste from the operation and decommissioning of a fusion power plant is a common goal of fusion development programs in Europe and in the US. Approaches differ, according to national regulations, and include reuse and recycling, clearance for non-active disposal or free-release recycling, and shallow land burial. Adopting the minimization of active waste volume as a design requirement leads to a Low Activation Design if properly optimized for materials choices. Power plant studies, both ARIES in the US and the PPCS in Europe, are adopting strategies to meet such requirements. International collaboration, particularly in the frame of an IEA co-operative program, provides benefits in the development of waste management strategies. C1 UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. TSI Res Inc, Solana Beach, CA 92075 USA. Idaho Natl Lab, Fus Safety Program, Idaho Falls, ID 83415 USA. Politecn Torino, Energet Dept, I-10129 Turin, Italy. RP Taylor, NP (reprint author), UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. RI Zucchetti, Massimo/P-9229-2016 OI Zucchetti, Massimo/0000-0003-4457-3321 NR 24 TC 6 Z9 6 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 350 EP 356 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100011 ER PT J AU Martovetsky, N Michael, P Minervini, J Radovinsky, A Ando, T Isono, T Kato, T Nakajima, H Nishijima, G Nunoya, Y Sugimoto, M Takahashi, Y Tsuji, H AF Martovetsky, N Michael, P Minervini, J Radovinsky, A Ando, T Isono, T Kato, T Nakajima, H Nishijima, G Nunoya, Y Sugimoto, M Takahashi, Y Tsuji, H TI First test results on ITER CS model coil and CS insert SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID AC LOSS; CABLE; FABRICATION; COMPLETION; CONDUCTOR AB The Inner and Outer modules of the Central Solenoid Model Coil (CSMC) were built by US and Japanese home teams in collaboration with European and Russian teams to demonstrate the feasibility of a superconducting Central Solenoid for ITER and other large tokamak reactors. The CSMC mass is about 120 t, OD is about 3.6 m and the stored energy is 640 MJ at 46 kA and peak field of 13 T. Testing of the CSMC and the CS Insert took place at the Japan Atomic Energy Research Institute (JAERI) from mid March until mid August 2000. This paper presents the main results of the tests performed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. ITER Naka Joint Work Site, Naka, Ibaraki 31101, Japan. ENEA CR Frascati, I-00044 Frascati, RM, Italy. Max Planck Inst Plasmaphys, EFDA CSU Garching, D-85748 Garching, Germany. RP Martovetsky, N (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. RI Nishijima, Gen/B-8804-2009; OI Nishijima, Gen/0000-0001-7493-0559; Michael, Philip/0000-0003-4906-6169 NR 18 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 359 EP 366 PN 2 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100012 ER PT J AU Heitzenroeder, PJ Meade, DM Thome, RJ AF Heitzenroeder, PJ Meade, DM Thome, RJ CA FIRE Project Team TI Engineering status of the Fusion Ignition Research Experiment (FIRE) SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB FIRE is a compact, high field tokamak being studied as an option for the next-step in the US magnetic fusion energy program. FIRE's programmatic mission is to attain, explore, understand, and optimize alpha-dominated plasmas to provide the knowledge necessary for the design of attractive magnetic fusion energy systems. This study began in 1999 with broad participation of the US fusion community, including several industrial participants. The design under development has a major radius of 2 m, a minor radius of 0.525 m, a field on axis of 10T and capability to operate at 12T with upgrades to power supplies. Toroidal and poloidal field magnets are inertially cooled with liquid nitrogen. An important goal for FIRE is a total project cost in the $1B range. This paper presents an overview of the engineering details' which were developed during the FIRE preconceptual design study in FY99 and 00. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. RP Heitzenroeder, PJ (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 374 EP 377 PN 2 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100014 ER PT J AU Ulrickson, MA Baxi, C Brooks, J Driemeyer, D Hassenein, A Kessel, CE Nelson, BE Rognlein, T Wesley, JC AF Ulrickson, MA Baxi, C Brooks, J Driemeyer, D Hassenein, A Kessel, CE Nelson, BE Rognlein, T Wesley, JC TI Design of the Fusion Ignition Research Experiment (FIRE) plasma facing components SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID REDEPOSITION; DIVERTOR; EROSION AB A design study of a Fusion Ignition Research Experiment (FIRE) is underway to investigate and assess near term opportunities for advancing the scientific understanding of self-heated fusion plasmas. The emphasis for the FIRE program is on understanding the behavior of plasmas dominated by alpha heating (Q greater than or equal to 5). Study activities have focused on the technical evaluation of a compact, high field, highly shaped tokamak. One of the key issues for the design is to find suitable plasma facing components (PFCs). We have investigated a variety of plasma edge and divertor conditions ranging from reduced recycling high heat flux conditions (attached) to reduced heat flux detached operation. The inner divertor detaches easily while impurities must be added to the outer divertor to achieve detachment. The outer divertor and private space baffle will have to be actively cooled. The plasma-facing surface of the divertor is tungsten bonded to a CuCrZr heat sink. The remainder of the PFCs are beryllium coated copper attached to the vacuum vessel. Plasma current disruptions impose strong constraints on the design. Appreciable PFC surface melting and evaporation and onset of "plasma shielding" are expected. The forces induced on the PFC due to disruptions determine the size of the attachment of the PFC to the vacuum vessel. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Gen Atom Co, San Diego, CA 92186 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Boeing Co, St Louis, MO 63166 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ulrickson, MA (reprint author), Sandia Natl Labs, POB 5800,MS-1129, Albuquerque, NM 87185 USA. NR 10 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 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 378 EP 382 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100015 ER PT J AU Brown, T AF Brown, T TI Fusion Ignition Research Experiment system integration SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB This paper describes the current status of the FIRE (Fusion Ignition Research Experiment) configuration and the integration of the major subsystem components. FIRE has a major radius of 2 m, a field on axis of 10T, a plasma current of 6.4 MA. It is capable of Is-second pulses when operated with DT and 26 s when operated with DD. The general arrangement consists of sixteen wedged TF (toroidal field) coils that surround a free standing central solenoid, a double wall vacuum vessel and internal plasma facing components that are segmented for maintenance through horizontal ports. Large rings located outside the TF coils are used to obtain a load balance between wedging of the intercoil case structure and wedging at the upper/lower inboard corners of the TF coil winding. The magnets are liquid nitrogen cooled and the entire device is surrounded by a thermal enclosure. The double wall vacuum vessel integrates cooling and shielding in a shape that maximizes shielding of ex-vessel components. Within the vacuum vessel, plasma-facing components frame the plasma. First wall tiles are attached directly to inboard and outboard vacuum vessel walls. The divertor is designed for a high triangularity, double-null plasma with a short inner null point-to-wall distance and near vertical outer divertor flux line. The FIRE configuration has been developed to meet the physics objectives and subsystem requirements in an arrangement that allows remote maintenance of in-vessel components and hands-on maintenance of components outside the TF boundary. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Brown, T (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 389 EP 392 PN 2 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100017 ER PT J AU Uckan, NA Wesley, JC AF Uckan, NA Wesley, JC TI Physics design guidelines for estimating plasma performance in a burning plasma experiment (FIRE) SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB The physics design guidelines for a next step, high-field tokamak, burning plasma experiment (FIRE, Fusion Ignition Research Experiment) have been developed as an update of the ITER Physics Basis (IPB). The plasma performance attainable in FIRE (or any next-step device) is affected by many physics issues, including energy confinement, L-to-H-mode power transition thresholds, MHD stability/beta limit, density limit, helium accumulation/removal, impurity content, sawtooth effects, etc. Design basis and guidelines are provided in each of these areas, along with sensitivities and/or uncertainties involved. The overall basic device parameters and features for FIRE (R = 2 m, a = 0.525 m, kappa (95) similar to 1.8, delta (95) similar to 0.4 q(95) > 3, B = 10-12 T, I = 6.45-7.7 MA, P-fus similar to 100-200 MW, Q similar to 5-10) are consistent with these guidelines and uncertainties if the potential design upgrade option (12 T, 8 MA) is considered as part of the main design option. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Gen Atom Co, Fus Grp, San Diego, CA 92186 USA. RP Uckan, NA (reprint author), Oak Ridge Natl Lab, POB 2009,MS-8071, Oak Ridge, TN 37831 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 398 EP 402 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100019 ER PT J AU Houlberg, WA AF Houlberg, WA TI Burning plasma physics issues illustrated by simulations of FIRE SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID REACTOR AB Plasma startup and operating issues are examined for a burning plasma using WHIST [1] simulations of the Fusion Ignition Research Experiment (FIRE) design [2]. Fueling and density profile control issues are illustrated through pellet launch from the inboard side of the plasma. Auxiliary fast wave ion cyclotron heating and current drive are used to identify plasma startup and burn control issues. It is shown that the current rampup and bootstrap current strongly influence the evolution of the safety factor, and can be tailored to produce sawtooth-free operation for about 20 seconds of burn in well-confined high confinement mode (H-mode) plasmas. Furthermore, it is also possible to maintain a reversed magnetic configuration that could allow access to the improved core confinement seen in present experiments. Access to II-mode operation is influenced by the fueling, heating and current startup waveforms. Maintenance of II-mode conditions may require either hysterisis in the high to low confinement (H-L) back-transition or continued auxiliary heating if the fusion power is insufficient. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Houlberg, WA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 8 TC 0 Z9 0 U1 1 U2 2 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 403 EP 407 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100020 ER PT J AU Baxi, CB Ulrickson, MA Driemeyer, DE Heitzenroeder, P AF Baxi, CB Ulrickson, MA Driemeyer, DE Heitzenroeder, P TI Thermal hydraulic analysis of FIRE divertor SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB The Fusion Ignition Research Experiment (FIRE) is being designed as a next step in the U.S. magnetic fusion program, The FIRE tokamak has a major radius of 2 m, a minor radius of 0.525 m, and liquid nitrogen cooled copper coils. The aim is to produce a pulse length of 20 s with a plasma current of 6.6 MA and with alpha dominated heating. The outer divertor and baffle of FIRE are water cooled. The worst thermal condition for the outer divertor and baffle is the baseline D-T operating mode (10 T, 6.6 MA, 20 s) with a plasma exhaust power of 67 MW and a peak heat flux of 20 MW/m(2). A swirl tape (ST) heat transfer enhancement method is used in the outer divertor cooling channels to increase the heat transfer coefficient and the critical heat flux (CHF). The plasma-facing surface consists of tungsten brush. The finite element (FE) analysis shows that for an inlet water temperature of 30 degreesC, inlet pressure of 1.5 MPa and a flow velocity of 10 m/s, the incident critical heat flux is greater than 30 MW/m(2). The peak copper temperature is 490 degreesC, peak tungsten temperature is 1560 degreesC, and the pressure drop is less than 0.5 MPa. All these results fulfill the design requirements. C1 Gen Atom Co, San Diego, CA 92186 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Boeing Co, St Louis, MO 63166 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Baxi, CB (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 408 EP 411 PN 2 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100021 ER PT J AU Nelson, B Burgess, T Brown, T Fan, HM Heitzenroeder, P AF Nelson, B Burgess, T Brown, T Fan, HM Heitzenroeder, P TI Fusion Ignition Research Experiment vacuum vessel design and configuration SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB The design status of the vacuum vessel for the Fusion Ignition Research Experiment (FIRE) is presented. The purpose and configuration of the various components of the vessel are described, along with the results of preliminary structural analysis. It appears that a vessel can be designed to meet the requirements within the rather restricted space constraints. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Nelson, B (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 412 EP 416 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100022 ER PT J AU Dilling, DA Brown, T AF Dilling, DA Brown, T TI Fire facilities and site requirements SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB This paper describes the buildings and balance of plant systems required to support the Fusion Ignition Research Experiment (FIRE) Project. Facilities and systems are developed on the basis of a "greenfield" site, with no benefit for existing facilities, but also without any constraints on the potential arrangement. Because FIRE will operate deuterium-tritium plasmas for pulse lengths on the order of 20 seconds, FIRE will require a moderate on-site tritium inventory. FIRE buildings and systems must be designed and licensed to comply with regulations for nuclear facilities. They must also include systems to manage tritium and tritiated water, activated dust, and radioactive waste material. Maintenance activities on FIRE will require the use of remote handling systems to remove and transport tokamak parts to hot cell facilities. Major tokamak service connections will be required to feed power to the copper magnet system and deliver plasma-heating energy to ICRF antennae. Competition for access to the tokamak for service connections and repair activities will constrain the overall arrangement and routing of services. This paper examines the design implications for the fuel supply, vacuum pumping, fuel recovery, cooling, and other balance of plant systems that contribute to the control of radioactive materials. It also examines the design implications for the tokamak test cell, hot cells, structures to house key services, and routing of service connections to the tokamak. Site requirements, a generic site plan, and conceptual building arrangements are provided. C1 Oak Ridge Natl Lab, La Jolla, CA 92037 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ USA. RP Dilling, DA (reprint author), Oak Ridge Natl Lab, 855 La Jolla Corona Court, La Jolla, CA 92037 USA. NR 3 TC 0 Z9 0 U1 0 U2 2 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 417 EP 421 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100023 ER PT J AU Neumeyer, C Woolley, R AF Neumeyer, C Woolley, R TI Electric power supply options for FIRE SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB The FIRE experiment(1) will present a net electric power demand approaching 1000MW for 10's of seconds, repeated once every 2 hours, delivered to the load via thyristor AC/DC converters which exhibit a widely varying power factor. The issues associated with the supply of such a load from the utility grid can be divided into two categories: Technical transmission line power flow vs, capacity voltage deviation within the grid vs, limits frequency deviation within the grid vs, limits loading of electrical equipment (e.g. generators) control of power generation (e.g. steam turbines) Operational control and monitoring of grid power now coordination of protection systems repetitive cycling of power system equipment allowance for contingency on tie line power flows power flow reversal harmonic content of load power and energy monitoring, billing rate structure The technical issues are amenable to analysis using well developed tools, models, and methods which have been in use for many years by the electric utility industry. The operational issues are less clear cut (particularly in the era of deregulation) and are more site dependant. This paper focuses on the technical issues and describes methods which can be used to reduce the impact of the load on the grid. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Neumeyer, C (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 13 TC 0 Z9 0 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 422 EP 428 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100024 ER PT J AU Crowell, JA Blanchard, JP AF Crowell, JA Blanchard, JP TI Electromagnetic disruption effects in the ARIES-RS tokamak design SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB A model of the induced currents and resultant electromagnetic forces and stresses during a disruption event in the ARIES-RS tokamak design is presented. Like many other power reactor concepts, the ARIES-RS has a modular design consisting of toroidally segmented internal structures to limit disruption induced currents and facilitate maintenance. During a disruption, currents driven in these structures cross the large toroidal magnetic field producing substantial electromagnetic forces. To consider these effects, a transient three-dimensional electromagnetic finite element model of the ARIES-RS device was created, implemented by the commercial code ANSYS. The same code was used for dynamic structural analysis. The model includes all major components (the first wall, blankets, divertor plates, stabilizing shells, vacuum vessel, shields) electromagnetically coupled together. The magnets are assumed to remain energized during the disruption. The plasma current decay is prescribed, not coupled with the current in the structure. Halo currents and and vertical displacement events, which may produce larger forces than found in this study, are not considered. The results illuminate important design tradeoffs. For a centered fast plasma current quench, the outboard first wall/blanket modules were found to experience the most severe loading. Current in the sidewalls generate forces that produce large torques on these structures. Supports are needed to react these loads; however, thermal stress considerations drive designs toward a first wall with a compliant support system. Thus, supports needed to reinforce against disruption loads can lower the maximum permissible heat flux on the first wall. Further, electromagnetic pressure on the first wall requires a factor of two reduction in the coolant channel width in some regions, resulting in higher pumping power. Extension of the results to other modular tokamak designs is discussed. Color versions of the figures are available on the world wide web at http://silver.neep.wisc.edu/disrupt or by contacting the authors. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Crowell, JA (reprint author), Sandia Natl Labs, POB 969,MS9024, Livermore, CA 94551 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 434 EP 438 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100026 ER PT J AU Petti, DA Merrill, BJ Moore, RL Longhurst, GR El-Guebaly, L Mogahed, E Henderson, D Wilson, P Abdou, A AF Petti, DA Merrill, BJ Moore, RL Longhurst, GR El-Guebaly, L Mogahed, E Henderson, D Wilson, P Abdou, A TI Safety and environment assessment of ARIES-AT SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID LITHIUM ALLOY AB ARIES-AT is a 1000 MWe conceptual fusion power plant design with a very low projected cost of electricity. The design contains many innovative features to improve both the physics and engineering performance of the system. From the safety and environmental perspective, there is greater depth to the overall analysis than in past ARIES studies. For ARIES-AT, the overall spectrum of off-normal events to be examined has been broadened. They include conventional loss of coolant and loss of flow events, an ex-vessel loss of coolant, and in-vessel off-normal events that mobilize in-vessel inventories (e.g. tritium and tokamak dust) and bypass primary confinement such as a Loss of Vacuum and an in-vessel loss of coolant with bypass. This broader examination of accidents improves the robustness of the design from the safety perspective and gives additional confidence that the facility can meet the no-evacuation requirement. We also provide a systematic assessment of the design to address key safety functions such as confinement, decay heat removal, and chemical energy control. In the area of waste management, waste is classified by both the volume of the component and its hazard. In comparison to previous ARIES designs, the overall waste volume is less because of the compact design. C1 Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID 83415 USA. Univ Wisconsin, Fus Technol Inst, Madison, WI USA. RP Petti, DA (reprint author), Idaho Natl Engn & Environm Lab, Fus Safety Program, POB 1625, Idaho Falls, ID 83415 USA. OI Wilson, Paul/0000-0002-8555-4410 NR 12 TC 6 Z9 6 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 449 EP 457 PN 2 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100029 ER PT J AU Neumeyer, C AF Neumeyer, C CA NSTX Team TI National spherical torus experiment (NSTX) engineering overview & research results 1999-2000 SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB The NSTX is a new US facility for the study of plasma confinement, heating, and current drive in a low aspect ratio, spherical torus (ST) configuration. The ST configuration is an alternate magnetic confinement concept which is characterized by high P (ratio plasma pressure to magnetic field pressure) and low toroidal field compared to conventional tokamaks, and could provide a pathway to the realization of a practical fusion power source. NSTX achieved first plasma in February 1999, and since that time has completed and commissioned all components and systems within the machine proper. Routine operation with inductively driven plasma current less than or equal to 1MA and flat top less than or equal to0.3 seconds has been established, and the ohmic characterization phase of the research program is underway. Radio Frequency (RF) and Neutral Beam Injection (NBI) systems have been installed and the first heating experiments are now underway. This paper describes the NSTX mission, gives an overview of the engineering design, and summarizes the research results obtained thus far. C1 Univ Washington, ORNL, PPPL, Seattle, WA 98195 USA. Columbia Univ, LANL, GA, New York, NY 10027 USA. Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Neumeyer, C (reprint author), Univ Washington, ORNL, PPPL, Seattle, WA 98195 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 469 EP 472 PN 2 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100032 ER PT J AU Schmidt, JA Larson, S Pueyo, M Rutherford, PH Jassby, DL AF Schmidt, JA Larson, S Pueyo, M Rutherford, PH Jassby, DL TI US fusion energy future SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Fusion implementation scenarios for the United States have been developed. The dependence of these scenarios on both the fusion development and implementation paths has been assessed. A range of implementation paths has been studied. The deployment of CANDU fission power plants in Canada and the deployment of fission power plants in France have been assessed as possible models for U.S. fusion deployment. The waste production and resource (including tritium) needs have been assessed. The conclusion that can be drawn from these studies is that it is challenging to make a significant impact on energy production during this century. However, the rapid deployment of fission power plants in Canada and France supports fusion implementation scenarios for the U.S. with significant power production during this century. If we can meet the schedule requirements then the resource needs and waste production are found to be manageable problems. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Schmidt, JA (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 9 TC 1 Z9 1 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 513 EP 517 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100039 ER PT J AU Gohar, Y AF Gohar, Y TI Flibe blanket concept for transmuting transuranic elements and long lived fission products SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB A Molten salt (Flibe) fusion blanket concept has been developed to solve the disposition problems of the spent nuclear fuel and the transuranic elements. This blanket concept can achieve the top rated solution, the complete elimination of the transuranic elements and the long-lived fission products. Small driven fusion devices with low neutron wall loading and low neutron fluence can perform this function. A 344-MW fusion power from D-T plasmas for thirty years with an availability factor of 0.75 can dispose of 70,000 tons of the US inventory of spent nuclear fuel generated up to the year 2015. In addition, the utilization of this blanket concept eliminates the need for a geological repository site for these materials, which is a major advantage. This application provides an excellent opportunity to develop and to enhance the public acceptance of the fusion energy for the future. The energy from the transmutation process is utilized to produce revenue. Flibe, lithium-lead eutectic, and liquid lead are possible candidates. The liquid blankets have several features, which are suited for this application. It can operate at constant thermal power without interruption for refueling by adjusting the concentration of the transuranic elements and lithium-6. These liquids operate at low-pressure, which reduces the primary stresses in the structure material. Development and fabrication costs of solid transuranic materials are eliminated. Burnup limit of the transuranic elements due to radiation effects is eliminated. Heat is generated within the liquid, which simplifies the heat removal process without producing thermal stresses. These blanket concepts have large negative temperature coefficient with respect to the blanket reactivity, which enhances the safety performance. These liquids are chemically and thermally stable under irradiation conditions, which minimize the radioactive waste volume. The operational record of the Molten Salt Breeder Reactor with Flibe was very successful, which established the technical bases for this application. This paper provides the technical analyses and the performance of the Flibe blanket concept as an example of this class of blankets. C1 Argonne Natl Lab, Fus Power Program, Technol Dev Div, Argonne, IL 60439 USA. RP Gohar, Y (reprint author), Argonne Natl Lab, Fus Power Program, Technol Dev Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 6 Z9 6 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 535 EP 540 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100043 ER PT J AU Gao, F Devanathan, R Weber, WJ AF Gao, F Devanathan, R Weber, WJ TI Si displacement cascades revealed by atomic-scale simulations in 3C-SiC SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID IRRADIATION-INDUCED AMORPHIZATION; SILICON-CARBIDE; COMPUTER-SIMULATION; MOLECULAR-DYNAMICS; DEFECT PRODUCTION; DAMAGE; METALS AB The primary damage by displacement cascades in 3C-SiC at 300 K has been studied by molecular dynamics (MD). A large number of cascades, with energies from 0.2 to 50 keV, have been simulated in order to investigate the effects of energy in defect production and clustering. The surviving defects are dominated by C interstitials and vacancies. The number of Frenkel pairs increases with increasing cascade energy, but the efficiency of their production declines with increasing energy in a similar fashion to that found in metals. Although the number of antisite defects is smaller than that of Frenkel pairs, their production also increases with increasing cascade energy. Most surviving defects are single interstitials and vacancies, and the tendency of interstitials to form clusters is very week. The size of the interstitial clusters is very small, which shows significantly different behavior than obtained by MD simulations in metals. The current results provide the statistics of the primary damage states in SiC as a function of primary knock-on energy, which are important in upscaling these results to model behavior over longer time and length scales. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Indian Inst Technol, Dept Met Engn, Chennai 600036, Tamil Nadu, India. RP Gao, F (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; Gao, Fei/H-3045-2012; Devanathan, Ram/C-7247-2008 OI Weber, William/0000-0002-9017-7365; Devanathan, Ram/0000-0001-8125-4237 NR 20 TC 5 Z9 5 U1 1 U2 5 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 574 EP 578 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100050 ER PT J AU Perlado, JM Dominguez, E Lodi, D Malerba, L Marian, J Prieto, J Salvador, M de la Rubia, TD Alonso, E Caturla, MJ Colombo, L AF Perlado, JM Dominguez, E Lodi, D Malerba, L Marian, J Prieto, J Salvador, M de la Rubia, TD Alonso, E Caturla, MJ Colombo, L TI Multiscale modeling of radiation damage of metals and SiC in inertial fusion reactors SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID SIMULATION; CASCADES AB The change in SiC properties under neutron irradiation is being experimentally assessed but it is actually far from being well understood. Using Molecular Dynamics (MDCASK-DENIM/LLNL), we show the existence of recombination barriers (metastable defects), and how they affect the cascade analysis. Displacement cascades have been systematically studied and the different role of both sublattices examined. Low-temperature amorphization by damage accumulation has been successfully simulated using MD in accordance with experiments, allowing the understanding (not possible from experiments) of the atomistic sequence of damage. We are also developing new methodologies (tight binding MD) to prove the adequacy of the interatomic potential to describe energetic of configurations needed for diffusion in SiC. The neutron source from target is obtained with time resolution, together with responses after transport in the IFE reactor. The comparison of different primary knock-on atom (PKA) energy spectra from different fusion reactors is given, which is a basic information for displacement cascade analysis. Those spectra are a direct consequence of the neutron spectra in the material (depending on protection). Supported by recent work on atomistic level, the effect of pulsed irradiation was concluded. The time between pulses has a key role in the annealing process of defects. The comparison with average continuous irradiation, and the different behaviour for vacancies and interstitials, are highlighted. C1 Univ Politecn Madrid, DENIM, Inst Fus Nucl, E-28006 Madrid, Spain. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Cagliari, Cagliari, Italy. RP Perlado, JM (reprint author), Univ Politecn Madrid, DENIM, Inst Fus Nucl, J Gutierrez Abascal 2, E-28006 Madrid, Spain. RI Caturla, Maria /D-6241-2012; Colombo, Luciano/D-9013-2013 OI Caturla, Maria /0000-0002-4809-6553; Colombo, Luciano/0000-0001-5335-4652 NR 23 TC 1 Z9 1 U1 0 U2 3 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 579 EP 584 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100051 ER PT J AU Morgan, MJ Tosten, MH AF Morgan, MJ Tosten, MH TI Tritium and decay helium effects on cracking thresholds and velocities in stainless steel SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Crack initiation and propagation were studied in three tritium-exposed stainless steels. The purpose was to measure cracking thresholds and velocities as a function of helium concentration in Type 21-6-9 stainless steel and compare the results to earlier measurements on Types 316L and 304L steels. Fracture toughness specimens were cut from forgings, fatigue-cracked and exposed to tritium at 423 K and 31 MPa; The samples were aged for selected times at 273 K to " build-in " He-3 from tritium decay. Tritium concentrations ranged from 0-2600 atomic parts-per-million (appm) and He-3 concentrations ranged from 0-600 appm. The samples were step-loaded at room temperature in air using a screw-driven mechanical testing machine and held at fixed displacement until crack initiation was detected. Crack propagation was monitored by continuously recording the drop in load until crack arrest. Threshold stress intensity was calculated from the load and the crack length at the end of the test. Crack velocities were determined from the load-time records and compliance relationships and verified on some samples using a DC potential-drop technique. The crack path was along grain and twin boundaries. For 21-6-9, the threshold for cracking decreased with increasing helium concentrations from about 90 MPa-m(1/2) (50 appm helium) to 25 MPa-m(1/2) (600 appm helium). Steady-state-crack velocities averaged 10(-7) m/s and was not strongly dependent on helium concentration. The data show that embrittlement of tritium-exposed stainless steels is a form of hydrogen embrittlement made worse by the hardening of the microstructure from nanometer-sized helium bubbles that build-in with tritium decay. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Morgan, MJ (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. NR 12 TC 1 Z9 1 U1 2 U2 3 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 590 EP 595 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100053 ER PT J AU Nagasaka, T Grossbeck, ML Muroga, T King, JF AF Nagasaka, T Grossbeck, ML Muroga, T King, JF TI Comparison of impact property of Japanese and US reference heats of V-4Cr-4Ti after gas-tungsten-arc welding SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Charpy impact tests of Japanese and US reference V-4Cr-4Ti alloys, NIFS-HEAT-1 (180 wppm oxygen) and US832665 (310 wppm Oxygen), were examined after gas-tungsten-are (GTA) welding in a purified argon atmosphere. To investigate the effects of further reduction of oxygen level in the fusion zone, filler wires made of HP thigh-purity V-4Cr-4Ti, 36 wppm oxygen) were used as well as those made of the reference alloys. Charpy impact property of NIFS-HEAT-1 in as-CTA-welded condition was superior to that of US832665. Use of the high-purity filler wires improved the impact property further. Good correlation was obtained between ductile-brittle-transition temperature (DBTT) and the oxygen level in the fusion zone. Since oxygen contamination from the atmosphere is avoidable by controlling its impurity level, oxygen reduction in weld materials, such as plate and wire, is crucial to obtain good weldability. Only contamination element detected in this study was hydrogen. Contamination occurred not only in fusion zone but also in base metal. Degassing of hydrogen after the welding may improve the impact property further. C1 Natl Inst Fus Sci, Gifu 5095292, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Nagasaka, T (reprint author), Natl Inst Fus Sci, Oroshi 322-6, Gifu 5095292, Japan. NR 8 TC 22 Z9 22 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 664 EP 668 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100067 ER PT J AU Meier, WR Callahan-Miller, DA Latkowski, JF Logan, BG Lindl, JD Peterson, PF AF Meier, WR Callahan-Miller, DA Latkowski, JF Logan, BG Lindl, JD Peterson, PF TI An engineering test facility for heavy ion fusion - Options and scaling SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB The engineering test facility (ETF) for inertial fusion energy (IFE) is the development step preceding a demonstration power plant. As such, it must demonstrate, in an integrated facility, performance of all the key subsystems required for fusion energy production, including target production, injection and tracking, beam propagation and focusing, target gain and yield, chamber response and recovery between shots, heat removal, tritium recovery, and plant safety. In the present work, we combine our current understanding of the target physics and technology, thick liquid wall chambers, and a heavy ion driver to investigate integrated system scaling and operating scenarios for an ETF for heavy ion fusion. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. RP Meier, WR (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 671 EP 677 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100068 ER PT J AU Nobile, A Gobby, P Schwendt, AM Steckle, WP Hoffer, JK Goodin, DT Besenbruch, GE Schultz, KR AF Nobile, A Gobby, P Schwendt, AM Steckle, WP Hoffer, JK Goodin, DT Besenbruch, GE Schultz, KR TI Concepts for fabrication of inertial fusion energy targets SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Future inertial fusion energy (IFE) power plants will have a Target Fabrication Facility (TFF) that must produce approximately 500,000 targets per day. To achieve a relatively low cost of electricity, the cost to produce these targets will need to be less than approximately $0.25 per target. In this paper the status on the development of concepts for a TFF to produce targets for a heavy ion fusion (HIF) reactor, such as HYLIFE II, and a laser direct drive fusion reactor such as Sombrero, is discussed. The baseline target that is produced in the HIF TFF is similar to the close-coupled indirect drive target designed by Callahan-Miller and Tabak at Lawrence Livermore Laboratory. This target consists of a cryogenic hohlraum that is made of a metal case and a variety of metal foams and metal-doped organic foams. The target contains a DT-filled CH capsule. The baseline direct drive target is the design developed by Bodner and coworkers at Naval Research Laboratory. HIF targets can be filled with DT before or after assembly of the capsule into the hohlraum. Assembly of targets before filling allows assembly operations to be done at room temperature, but tritium inventories are much larger due to the large volume that the hohlraum occupies in the fill system. Assembly of targets cold after filling allows substantial reduction in tritium inventory, but this requires assembly of targets at cryogenic temperature. A model being developed to evaluate the tritium inventories associated with each of the assembly and fill options indicates that filling targets before assembling the capsule into the hohlraum, filling at temperatures as high as possible, and reducing dead-volumes in the fill system as much as possible offers the potential to reduce tritium inventories to acceptable levels. Use of enhanced DT ice layering techniques, such as infrared layering can reduce tritium inventories significantly by reducing the layering time and therefore the number of capsules being layered. Current processes for fabrication of ICF capsules can most likely be easily scaled up to produce capsules at rates needed for an TFE plant. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87544 USA. Gen Atom Corp, San Diego, CA 92186 USA. RP Nobile, A (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Mail Stop C927, Los Alamos, NM 87544 USA. NR 8 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 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 684 EP 691 PN 2 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100070 ER PT J AU Abbott, R Pemberton, S Peterson, PF Sun, GP Wright, P Holmes, R Latkowski, J Moir, R Springer, K AF Abbott, R Pemberton, S Peterson, PF Sun, GP Wright, P Holmes, R Latkowski, J Moir, R Springer, K TI Cylindrical liquid jet grids for beam-port protection of thick-liquid heavy-ion fusion target chambers SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID DESIGN AB Thick-liquid pockets have the potential to protect structural materials and increase power density in heavy-ion fusion chambers. Here we show that cylindrical liquid jets have interesting advantages for creating shielding grids for heavy-ion beam lines. A cylindrical nozzle design with a very low convergence ratio was developed, and the fabrication methods needed for inexpensive numerically-controlled machining of large nozzle arrays demonstrated. Cylindrical jets were studied because they give the highest surface smoothness for a given degree of turbulence suppression, allow flow control to individual nozzles for control of jet pointing, and attenuate target-induced shocks effectively. Improved control of the grid geometry allows the driver energy to be delivered by a larger number of beams. These smaller beams-up to 160 in the example here-improve focusing and reduce neutron collimation up beam lines. C1 Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Abbott, R (reprint author), Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. NR 9 TC 11 Z9 11 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 732 EP 738 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100078 ER PT J AU Ying, AY Abdou, M Smolentsev, S Huang, H Kaita, R Maingi, R Morley, N Nelson, B Sketchley, T Ulrickson, M Woolley, R AF Ying, AY Abdou, M Smolentsev, S Huang, H Kaita, R Maingi, R Morley, N Nelson, B Sketchley, T Ulrickson, M Woolley, R TI MHD and heat transfer issues and characteristics for Li free surface flows under NSTX conditions SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB In the APEX study, one of the tasks focuses on the exploration and identification of the attractive options and issues for flowing liquid lithium walls in the NSTX device. In addition to constraints imposed by the machine, the operating conditions of the flowing liquid walls along the center stack and divertor areas are guided by MHD and heat removal requirements. In this paper, we present important MHD and heat removal issues and analysis for the proposed free surface lithium flows under NSTX conditions. It is shown that of all MHD effects, the one caused by the normal magnetic field is the most important. The flow over the center stack area is not affected by MHD interaction significantly, whereas flow over the inboard divertor undergoes strong MHD drag resulting in flow thickening by several times. The flow over the outboard divertor is essentially stopped. The analysis shows that a flow with an inlet velocity of 2 m/s and film thickness of about 4 mm can be established to provide surface temperature less than 400 degrees C for the center stack under a projected NSTX total heating power of 10 MW operation. C1 Univ Calif Los Angeles, Dept Mech & Aerosp Engn, Los Angeles, CA 90024 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ying, AY (reprint author), Univ Calif Los Angeles, Dept Mech & Aerosp Engn, Los Angeles, CA 90024 USA. NR 8 TC 5 Z9 5 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 739 EP 745 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100079 ER PT J AU Sze, DK McCarthy, K Sawan, M Tillack, M Ying, A Zinkle, S AF Sze, DK McCarthy, K Sawan, M Tillack, M Ying, A Zinkle, S TI Flibe assessments SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB An assessment of the issues on using flibe for fusion applications has been made. It is concluded that sufficient tritium breeding can be achieved for a flibe blanket, especially if a few cm of Be is include in the blanket design. a key issue is the control of the transmutation products such as TF and F-2 A REDOX (Reducing-Oxidation) reaction has to be demonstrated which is compatible to the blanket design. Also, MHD may have strong impact on heat transfer if the flow is perpendicular to the magnetic field. The issues associated with the REDOX reaction and the MHD issues have to be resolved by both experimental program and numerical solutions. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Idaho Natl Engineer & Environm Lab, Idaho Falls, ID USA. Univ Wisconsin, Madison, WI 53706 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Sze, DK (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Zinkle, Steven/0000-0003-2890-6915 NR 9 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 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 746 EP 752 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100080 ER PT J AU Moir, RW Bulmer, RH Gulec, K Fogarty, P Nelson, B Ohnishi, M Rensink, M Rognlien, TD Santarius, JF Sze, DK AF Moir, RW Bulmer, RH Gulec, K Fogarty, P Nelson, B Ohnishi, M Rensink, M Rognlien, TD Santarius, JF Sze, DK TI Thick liquid-walled, field-reversed configuration-magnetic fusion power plant SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID REACTOR; DESIGN AB A thick flowing layer of liquid (e.g., flibe-a molten salt, Sn80Li20 or Li-liquid metals) protects the structural walls of the field-reversed configuration (FRC) so that they can last the life of the plant even with intense 14 MeV neutron bombardment from the D-T fusion reaction. The surface temperature of the liquid rises as it passes from the inlet nozzles to the exit nozzles due to absorption of line and bremsstrahlung radiation, and neutrons. The surface temperature can be reduced by enhancement of convection near the surface to transport hot surface liquid into the cooler interior. The resulting temperature for evaporation estimates called, T,m is 660, 714 and 460 degreesC for flibe, SnLi and Li, where thermal conductivity was assumed enhanced by a factor of ten for flibe. The corresponding evaporative flux from the wall must result in an acceptable impurity level in the core plasma. The shielding of the core by the edge plasma is modeled with a 2D transport code for the resulting impurity ions; these ions are either swept out to the distant end tanks, or diffuse to the hot plasma core. The calculations show core impurity levels adequately low for Li and Sn80Li20 but is about ten times too large for flibe. An auxiliary plasma between the edge plasma and the liquid wall can further attenuate evaporating flux of atoms and molecules by ionization. The current in this auxiliary plasma might serve as the antenna for the current drive method, which produces a rotating magnetic field. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Kansai Univ, Suita, Osaka, Japan. Univ Wisconsin, Madison, WI 53706 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Moir, RW (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-637, Livermore, CA 94550 USA. NR 11 TC 7 Z9 7 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 758 EP 767 PN 2 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100082 ER PT J AU Sterbentz, JW O'Brien, JE Anderl, RA Smolik, GR Petti, DA McCarthy, KA AF Sterbentz, JW O'Brien, JE Anderl, RA Smolik, GR Petti, DA McCarthy, KA TI Design of the FLIQURE experiment SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB A preliminary design is presented for the FLIQURE or Fusion LIQUid Release Experiment. This experimental system is designed to measure the mobilization of tritium, fluorine, and other constituents in molten Flibe following trace neutron irradiation at fusion-relevant temperatures (500-1000 degreesC). Trace neutron irradiation is achieved using a spontaneous fission Cf-252 source that produces a relatively uniform concentration of tritium in the Flibe. The experimental goals aim to better understand the mechanisms, mobilization rates, and physiochemical forms of tritium mobilized from the Flibe along with other potentially detectable radioactive isotopes and toxic-material species under inert-gas, air, and steam-ingress conditions. System design details are discussed which include neutronic studies to optimize tritium production, thermal design to maintain and isolate molten Flibe, and instrumentation to meet experimental goals. C1 INEEL, Idaho Falls, ID 83415 USA. RP Sterbentz, JW (reprint author), INEEL, POB 1625, Idaho Falls, ID 83415 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 773 EP 778 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100084 ER PT J AU Sze, DK Sawan, ME Cheng, ET AF Sze, DK Sawan, ME Cheng, ET TI Impact of transmutations in fusion environment on flibe chemistry SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Transmutation rates of Li, Be and F are calculated for a typical flibe blanket. The results concluded that the transmutation rate of F is more than double that of Be. Because of the high destruction rate of fluorine, there will be no free fluorine in the molten salt. Therefore, experimental program to address the chemistry control of flibe does not have to worry about the issues associated with free fluorine as long as kinetics are favorable (likely). Also, this calculation defines the chemical state of flibe after irradiation. This chemical state needs to be simulated closely for the flibe chemistry control experiments. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Wisconsin, Madison, WI 53706 USA. TSI Res Inc, Solana Beach, CA 92075 USA. RP Sze, DK (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 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 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 789 EP 792 PN 2 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100087 ER PT J AU Latkowski, JF Meier, WR AF Latkowski, JF Meier, WR TI Heavy-ion fusion final focus magnet shielding designs SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB At the Thirteenth International Symposium on Heavy Ion Inertial Fusion (HIF Symposium), we presented magnet shielding calculations for 72-, 128, 200, and 288-beam versions of the HYLIFE-II power plant design.(1-2) In ail cases, we found the radiation-limited lifetimes of the last set of final focusing magnets to be unacceptably short.(1) Since that time, we have completed follow-on calculations to improve the lifetime of the 72-beam case. Using a self-consistent final focusing model, we vary parameters such as the shielding thicknesses and compositions, focusing length, angle-of-attack to the target, and the geometric representation of the flibe pocket, chamber, and blanket. By combining many of these shielding features, we demonstrate a shielding design that would enable the last set of final focusing magnets to survive for the lifetime of the power plant. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Latkowski, JF (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-632, Livermore, CA 94551 USA. NR 7 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 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 798 EP 803 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100089 ER PT J AU Wong, CPC Barleon, L Corradini, M Fogarty, P Ghoniem, N Majumdar, S Malang, S Mattas, R McCarthy, K Merrill, B Murphy, J Nelson, B Nygren, R Sawan, M Sharafat, S Sviatoslavsky, I Zinkle, S AF Wong, CPC Barleon, L Corradini, M Fogarty, P Ghoniem, N Majumdar, S Malang, S Mattas, R McCarthy, K Merrill, B Murphy, J Nelson, B Nygren, R Sawan, M Sharafat, S Sviatoslavsky, I Zinkle, S TI Evaluation of the tungsten alloy vaporizing lithium first wall and blanket concept SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UT SP Amer Nucl Soc AB This paper reports the results of the second phase evaluation of the EVOLVE W-alloy first wall and blanket design cooled by vaporizing lithium. For the transpiration-cooled first wall and blanket concept, we identify the need to further quantify the data of lithium superheat from W-alloy heated surface and bulk lithium slabs. For the boiling lithium blanket, we identify the need to elucidate the impacts of magnetic field on various stable-boiling regimes. We also find that this FW/blanket concept should have no problem in achieving adequate nuclear performance. With the addition of passive cooling loops, the concept has a strong possibility of achieving the safety requirement of not needing a public evacuation plan under the loss of power accident conditions. Even though the irradiated W-alloy may be subject to embrittlement, due to the relatively low system pressure of the design, it is shown to be able to withstand a large number of cracks. The fundamental issues of W-alloy properties under high neutron fluence irradiation and the components fabrication technique remain. Preliminary investigations of W-alloy fabrication and heat flux removal through SBIR programs have begun and the initial results are encouraging. We recommend that the investigation of critical issues of the EVOLVE concept continue since this innovative design has a good possibility of showing a way to achieve high performance and passively safe designs that are necessary for the utilization of fusion power. C1 Gen Atom Co, San Diego, CA 92186 USA. Univ Wisconsin, Madison, WI USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Forschungszentrum Karlsruhe, FZK, Karlsruhe, Germany. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wong, CPC (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. RI Ghoniem, Nasr/A-9799-2008; OI Zinkle, Steven/0000-0003-2890-6915 NR 19 TC 15 Z9 16 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 815 EP 822 PN 2 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100092 ER PT J AU Youssef, MZ Morley, NB Sze, DK AF Youssef, MZ Morley, NB Sze, DK TI Nuclear performance of the thin-liquid FW concept of the CLIFF design SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID POWER; REACTOR AB The nuclear performance of the thin Convective Liquid Flow First Wall (CLiFF) concept is investigated. Liquid walls-offer the advantage of protecting solid structure behind them from excessive damage from neutrons originated in the plasma and thus have the capability for high power density applications; the central research focus of the Advanced Power Extraction (APEX) study. In the present parametric and scoping work, several combinations of liquid breeder and structure type where investigated. The aim is to maximize local tritium breeding ratio (TBR), power multiplication, and ensuring that the vacuum vessel and toroidal coils are protected from excessive radiation. The candidate liquid breeders considered are Li, Flibe, and Sn-Li. Vanadium-alloy is deployed with Li while either Ferritic steel or SiC is deployed with Flibe and Sn-Li. Deployment of other refractory alloys and their impact on TBR was also studied. The introduction of a beryllium multiplier zone in the blanket was shown to enhance tritium production capability, particularly for those liquid breeders whose TBRs are marginal. C1 Univ Calif Los Angeles, Sch Engn & Appl Sci, Los Angeles, CA 90024 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Youssef, MZ (reprint author), Univ Calif Los Angeles, Sch Engn & Appl Sci, 43-133 Eng 4 Bldg, Los Angeles, CA 90024 USA. NR 14 TC 6 Z9 6 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 839 EP 845 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100096 ER PT J AU Marshall, TD Youchison, DL Cadwallader, LC AF Marshall, TD Youchison, DL Cadwallader, LC TI Modeling the Nukiyama curve for water-cooled fusion divertor channels SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID HEAT-TRANSFER; TUBES AB A conclusive safety assessment of a fusion reactor requires that the thermal response of the divertor assembly is known with a high degree of accuracy. Such accuracy is mandated because the divertor assembly is subjected to the highest levels of incident heat flux within the reactor. In order to accurately predict the thermal response of the divertor's cooling channels, it is necessary to have a complete model of the Nukiyama boiling curve for the water conditions of interest. Currently published models of the Nukiyama curve for fusion divertor channels have only included the regimes of forced convection, partially and fully developed nucleate boiling, and the local CHF. This paper presents a model that includes these pre-CHF regimes and the post-CHF regime of transition boiling. The model is unique because (1) it tightly integrates the respective heat transfer correlations and makes heat transfer predictions for the water conditions and incident heat fluxes that are fusion-specific, (2) predicts post-CHF heat transfer properties for a swirl tape divertor channel, and (3) validates its predictions via comparison with experimental data. Based on these three points, this model is considered as one of the best available methods for predicting the Nukiyama curve for a water-cooled fusion device. C1 CEA, LECC, SERSI, F-13108 St Paul Durance, France. Sandia Natl Labs, Albuquerque, NM 87185 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Marshall, TD (reprint author), CEA, LECC, SERSI, F-13108 St Paul Durance, France. RI Cadwallader, Lee/F-6933-2014; OI Youchison, Dennis/0000-0002-7366-1710 NR 22 TC 6 Z9 6 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 849 EP 855 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100097 ER PT J AU Sharafat, S Demetriou, M Ghoniem, N Williams, B Nygren, R AF Sharafat, S Demetriou, M Ghoniem, N Williams, B Nygren, R TI Enhanced surface heat removal using a porous tungsten heat exchanger SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID FUSION APPLICATIONS AB A novel concept for drastically improving the surface heat load capability of helium-cooled tungsten-alloy tubes is being developed for plasma facing components. The concept utilizes ultra-low density (90% porosity) W-foam, which is chemical-vapor-deposited inside a W-tube. The W-foam enhances the effective heat transfer coefficient inside the tube by significantly increasing the conduction path from the wall to the coolant fluid. A mockup of the W-tube/W-foam system has been constructed for testing at the helium loop and electron beam facility at Sandia National Laboratories, Albuquerque, NM. A finite element model (FEM) was constructed based on a 3-D solid model of the test section. The enhanced heat transfer coefficient was determined based on fundamental heat transfer principles through porous media. The porous tungsten heat exchanger tube exhibits a 3 fold improved surface heat load capability relative to a plain W-tube at temperatures above 1200 degreesC. C1 Univ Calif Los Angeles, Mech & Aero Engn Dept, Los Angeles, CA 90095 USA. Ultramet Inc, Pacoima, CA 91331 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sharafat, S (reprint author), Univ Calif Los Angeles, Mech & Aero Engn Dept, Los Angeles, CA 90095 USA. RI Ghoniem, Nasr/A-9799-2008 NR 10 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 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 863 EP 867 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100099 ER PT J AU Venhaus, TJ Causey, RA AF Venhaus, TJ Causey, RA TI Analysis of thermal desorption spectra to understand the migration of hydrogen in tungsten SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID REACTOR AB Tungsten and tungsten alloys are candidate plasma-facing materials for future fusion reactors due to their excellent thermal properties and sputtering characteristics. A Sandia National Laboratories experimental program investigated the retention and release characteristics of hydrogen isotopes in tungsten and tungsten doped with 1% lanthanum oxide. A single model based on a high recombination rate coefficient, enhanced diffusivity in the implant zone for high flux experiments, and a 1.4 eV trap was capable of simulating all of the data accumulated in the experimental program. In this report, the model is now applied to data obtained by other researchers examining hydrogen migration in tungsten. Almost without exception, the model was able to accurately duplicate the hydrogen isotope retention and release with the single variable of trap density. C1 Sandia Natl Labs, Los Alamos, NM 87505 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Venhaus, TJ (reprint author), Sandia Natl Labs, POB 1663, Los Alamos, NM 87505 USA. NR 18 TC 8 Z9 8 U1 0 U2 5 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 868 EP 873 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100100 ER PT J AU Longhurst, GR Merrill, BJ AF Longhurst, GR Merrill, BJ TI TMAP2000: An improved code for tritium calculations SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB The Tritium Migration Analysis Program (TMAP) was an aid in performing safety analyses of fusion systems using combined heat and mass transport calculations. Upgraded to TMAP4, it was verified and validated at the INEEL. The further upgrade of the code to TMAP2000 was accomplished in response to several needs. TMAP and TMAP4 had the capacity to deal with only a single trap for diffusing gaseous species in solid structures. TMAP2000 has been revised to include up to three separate traps and to keep track separately of each of up to 10 diffusing species in each of the traps. The original code experienced problems in dealing with heteronuclear molecule formation such as HD and DT. That has been corrected. A further sophistication is the addition of non-diffusing surface species and surface binding energy dynamics options. TMAP2000 will accommodate up to 30 such surface species. Additionally, TMAP2000 allows simulation of surface fluxes dependent on a surface binding energy and an adsorption barrier energy. All of the previously existing features for heat transfer, flows between enclosures, and chemical reactions within the enclosures have been retained, but the allowed problem size and complexity have been significantly increased to take advantage of the greater memory and speed available on modern computers. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Longhurst, GR (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 874 EP 879 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100101 ER PT J AU Molokov, S Cox, I Reed, CB AF Molokov, S Cox, I Reed, CB TI Theoretical investigation of liquid metal MHD free surface flows for Alps SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Free surface plasma facing components (PFCs) offer the potential to solve the lifetime issues limiting current solid surface designs for tokamak fusion reactors by eliminating the problems of erosion and thermal stresses accompanying solid surface designs. The moving PFC free surfaces provide the possibility of absorbing impurities and possibly helium for removal outside of the plasma chamber. Free surface PFCs may also offer more creative possibilities for heat removal and higher thermal conversion efficiencies for the entire system. Design requirements for PFCs include handling similar to 50% of the plasma heat flux and similar to 90% of the ion flux. Magnetohydrodynamic (MHD) liquid metal flows with free surfaces are discussed with reference to Advanced Limiter-divertor Plasma-facing Systems (ALPS) program. Specific MHD issues for the jet divertor are outlined. Results for the rivulet flow and for the thermocapillary, or Marangoni, flow in a jet are presented. C1 Coventry Univ, MIS, Coventry CV1 5FB, W Midlands, England. Argonne Natl Lab, Fus Power Program, Argonne, IL 60439 USA. RP Molokov, S (reprint author), Coventry Univ, MIS, Priory St, Coventry CV1 5FB, W Midlands, England. OI Molokov, Sergei/0000-0002-8633-345X NR 6 TC 5 Z9 6 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 880 EP 884 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100102 ER PT J AU Youchison, DL North, MT AF Youchison, DL North, MT TI Thermal performance of a dual-channel, helium-cooled, tungsten heat exchanger SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Helium-cooled, refractory heat exchangers are now under consideration for first wall and divertor applications. These refractory devices take advantage of high temperature operation with large delta-Ts to effectively handle high heat fluxes. The high temperature helium can then be used in a gas turbine for high-efficiency power conversion. Over the last five years, heat removal with helium was shown to increase dramatically by using porous metal to provide a very large effective surface area for heat transfer in a small volume. Last year, the thermal performance of a bare-copper, dual-channel, helium-cooled, porous metal divertor mock-up was evaluated on the 30 kW Electron Beam Test System at Sandia National Laboratories. The module survived a maximum absorbed heat flux of 34.6 MW/m(2) and reached a maximum surface temperature of 593 degreesC for uniform power loading of 3 kW absorbed on a 2-cm(2) area. An impressive 10 kW of power was absorbed on an area of 24 cm(2) Recently, a similar dual-module, helium-cooled heat exchanger made almost entirely of tungsten was designed and fabricated by Thermacore, Inc. and tested at Sandia. A complete flow test of each channel was performed to determine the actual pressure drop characteristics. Each channel was equipped with delta-P transducers and platinum resistance temperature devices (RTDs) for independent calorimetry. One mass flow meter monitored the total flow to the heat exchanger, while a second monitored flow in only one of the channels. The thermal response of each tungsten module was obtained for heat fluxes in excess of 5 MW/m2 using 50 degreesC helium at 4 MPa. Fatigue cycles were also performed to assess the fracture toughness of the tungsten modules. A description of the module design and new results on flow instabilities are also presented. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Thermacore Inc, Lancaster, PA 17601 USA. RP Youchison, DL (reprint author), Sandia Natl Labs, POB 5800,MS-1129, Albuquerque, NM 87185 USA. OI Youchison, Dennis/0000-0002-7366-1710 NR 6 TC 9 Z9 9 U1 0 U2 3 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 899 EP 904 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100106 ER PT J AU Klepper, CC Niemel, J Hazelton, RC Yadlowsky, EJ Monteiro, OR AF Klepper, CC Niemel, J Hazelton, RC Yadlowsky, EJ Monteiro, OR TI Vacuum arc deposited boron carbide films for fusion plasma facing components SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID FILTERED CATHODIC VACUUM; THIN-FILMS; TORE-SUPRA; COATINGS; CARBON; SILICON; TOKAMAK; STREAMS AB Boron carbide is an ideal coating for radiofrequency antennas in magnetic fusion energy, due to a combination of desirable properties: high hardness at high temperature, high melting point, low Z and high thermal conductivity. In this paper, the feasibility of using vacuum are technology for coating antennas and other magnetic fusion energy plasma facing components is explored. This technique has the potential of producing much denser film than plasma spray and substantially higher deposition rates than magnetron sputtering. Tn addition, the use of hyper-thermal species may result in the formation of high thermal conductivity crystalline phase at lower deposition temperatures than would otherwise be expected. Finally, the compatibility of the vacuum are with ultra-high vacuum conditions raises the possibility of in situ repair of components in a fusion reactor. Initial deposition studies are presented, which produced primarily amorphous film, but with the correct stoichiometry and a high deposition rate (>10nm/s). The properties of this film are presented in this paper. Some of the properties of the vacuum are discharge, the first to be operated successfully with a sintered boron carbide cathode, are also presented. C1 HY Tech Res Corp, Radford, VA 24141 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Klepper, CC (reprint author), HY Tech Res Corp, 104 Ctr Court, Radford, VA 24141 USA. NR 31 TC 11 Z9 11 U1 0 U2 4 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 910 EP 915 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100108 ER PT J AU Petrie, TW Fenstermacher, ME Lasnier, CJ AF Petrie, TW Fenstermacher, ME Lasnier, CJ TI Implications of recent DIII-D experiments on plasma shaping for future tokamak designs SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID RADIATIVE DIVERTOR PLASMAS AB Advanced tokamaks use D-shaped cross-section plasmas to optimize fusion performance. In turn, the divertor (which handles heat and particles) must operate efficiently in these shaped plasmas. In this paper, we report on recent experiments at the DIII-D National Fusion Facility that compare the advantages/disadvantages of I) double-null (DN) versus single-null (SN) configurations, 2) particle pumping at low and high density, and 3) open versus tightly baffled diverters. The focus of this paper will be on the important engineering consequences of these physics results for future tokamak designs. Accurate control over the magnetic balance is required by the plasma shaping coils for DN land near-DN) operation because of the strong sensitivity of the heat flux to small changes in magnetic balance. Alternatively, additional protective armor may be needed for each divertor. We show that precise control over the strike point location by the coil system is important for lower density (attached) plasma operation, but much less so for higher density (detached) operation. We also find that minimizing the angle between the divertor structure and the divertor plasma legs is very useful in reducing the peak divertor heat flux for lower density (attached) plasmas but is of Limited benefit for higher density (detached) plasmas. Finally, the physics results imply that significant heating and damage at the divertor "slot" opening may occur, even if several heat flux scrape-off lengths are allowed for clearance. C1 Gen Atom Co, San Diego, CA 92186 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Petrie, TW (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 15 TC 6 Z9 6 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 916 EP 922 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100109 ER PT J AU Reyes, S Latkowski, JF del Rio, JG Sanz, J AF Reyes, S Latkowski, JF del Rio, JG Sanz, J TI Accident doses analysis of the SOMBRERO inertial fusion energy power plant design SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB SOMBRERO (solid moving breeder reactor) is a conceptual design of a 1000 MWe laser-driven inertial fusion energy (IFE) power plant. An important goal of the original study was the achievement of a safe and environmentally attractive reactor of relatively simple design. However, recent work has pointed out some key issues involving safety that were not completely addressed at that time, and which need to be reviewed in order to maximize the SOMBRERO design attractiveness. The present work uses a set of computer codes traditionally used for magnetic fusion safety studies (CHEMCON, MELCOR), which have been adopted and adapted for use in IFE safety analysis. Here we consider a loss of flow accident (LOFA) combined with simultaneous loss of vacuum accident (LOVA) produced by a breach in the confinement building. Although confinement failure would be a very unlikely event, it must be postulated in order to produce significant off-site doses. The CHEMCON code is used to simulate the longterm thermal transient in the reactor structures resulting from oxidation and radioactive decay heat. MELCOR is used to simulate a wide range of physical phenomena including thermal-hydraulics, heat transfer, aerosol physics and fusion product release and transport. As specified in the DOE Fusion Safety Standards, an off-site dose below 1 rem (10 mSv) is the requirement to avoid public sheltering and evacuation. The SOMBRERO accident analysis results will be evaluated according to this limit and suggestions will be made for improvements and future work. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Reyes, S (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-632, Livermore, CA 94550 USA. NR 10 TC 6 Z9 6 U1 0 U2 2 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 941 EP 945 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100113 ER PT J AU Reyes, S Latkowski, JF del Rio, JG Sanz, J AF Reyes, S Latkowski, JF del Rio, JG Sanz, J TI Progress in accident analysis of the HYLIFE-II inertial fusion energy power plant design SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UT SP Amer Nucl Soc AB The present work continues our effort to perform an integrated safety analysis for the HYLIFE-II inertial fusion energy (IFE) power plant design. Recently we developed a base case for a severe accident scenario in order to calculate accident doses for HYLIFE-II. It consisted of a total loss of coolant accident (LOCA) in which all the liquid flibe (Li(2)BeF(4)) was lost at the beginning of the transient. Results showed that the off-site dose was below the limit given by the DOE Fusion Safety Standards for public protection in case of accident, and that this dose was dominated by the tritium released during the accident. In order to further advance a complete safety analysis for HYLIFE-II, a range of other accident scenarios must be considered. In this work, we introduce a new version of the MELCOR thermal-hydraulics code recently developed by the Idaho National Engineering and Environmental Laboratory (INEEL) that uses flibe as the working fluid. We have focused on a loss of flow accident (LOFA), with simultaneous failure of the blanket structure and the beam Cubes that connect the chamber with the outside of the confinement building. This constitutes the bypass needed to communicate the target chamber with the environment. Once the release fractions of the various radioactivity sources are known, we calculate off-site doses under different conditions as a consequence of the accident. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Nacl Educ Distancia, Dpto Ingn Energet, ETS Ingn Ind, Madrid 28040, Spain. Univ Nacl Educ Distancia, Inst Fus Nucl, ETS Ingn Ind, Madrid 28040, Spain. RP Reyes, S (reprint author), Lawrence Livermore Natl Lab, POB 808,L-632, Livermore, CA 94550 USA. NR 15 TC 8 Z9 8 U1 0 U2 1 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 946 EP 950 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100114 ER PT J AU McCarthy, KA Petti, DA Khater, HY AF McCarthy, KA Petti, DA Khater, HY TI Comparison of the safety and environmental characteristics of refractory alloys under consideration in APEX SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID FUSION AB High temperature refractory alloys of tungsten, molybdenum and tantalum are under evaluation for use as structural materials in the Advanced Power Extraction Program (APEX) because of their ability to accommodate high wall loading and high temperature coolant. However, such materials tend to have undesirable safety and environmental characteristics relative to conventional reduced-activation fusion materials. These alloys have high decay heat and in some cases their activation results in the production of long-lived isotopes that would disqualify the material from being disposed of as low level waste. In addition, some of the alloys have oxides that are very volatile, which could be mobilized in accident scenarios in which air ingress is a concern. In this paper we compare the safety and environmental characteristics of these alloys with their low activation cousin (vanadium) in terms of decay heat, oxidation driven mobilization in air, and waste management. C1 Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID 83415 USA. Univ Wisconsin, Fus Technol Inst, Madison, WI 53706 USA. RP McCarthy, KA (reprint author), Idaho Natl Engn & Environm Lab, Fus Safety Program, POB 1625, Idaho Falls, ID 83415 USA. NR 17 TC 2 Z9 2 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 951 EP 955 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100115 ER PT J AU Latkowski, JF AF Latkowski, JF TI Measurement of the NIF gunite shielding composition and implications for neutron activation and worker doses SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB In December 1999 and January 2000, a 40-cm-thick spherical shell of sprayable concrete ("gunite") was applied to the exterior surface of the National Ignition Facility (NIF) target chamber. Glow-discharge mass spectroscopy has been used to determine the elemental composition of multiple gunite samples, which were collected at the time of application. These measured compositions are compared to the anticipated composition and both are used for neutron activation calculations, Contact dose rates are reported and implications for doses rates during operation and for the eventual facility decommissioning are discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Latkowski, JF (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-632, Livermore, CA 94551 USA. NR 5 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 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 956 EP 959 PN 2 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100116 ER PT J AU Latkowski, JF Reyes, S Besenbruch, GE Goodin, DT AF Latkowski, JF Reyes, S Besenbruch, GE Goodin, DT TI Preliminary safety assessment for an IFE target fabrication facility SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID HEAVY-ION; FUSION; DESIGN AB We estimate possible ranges of tritium inventories for an inertial fusion energy (IFE) target fabrication facility producing various types of targets and using various production technologies. Target fill is the key subtask in determining the overall tritium inventory for the plant. By segmenting the inventory into multiple, parallel production lines-each with its own fill canister-and including an expansion tank to limit releases, it appears possible for a target fabrication facility to meet the accident dose goals of 10 mSv (1 rem) set forth in the Department of Energy's Fusion Safety Standards. For indirect-drive targets, we calculate release fractions for elements from lithium to bismuth and show that nearly all elements meet the dose goal. Our work suggests directions for future R&D that will help reduce total tritium inventories and increase the flexibility of target fabrication facilities. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Gen Atom Co, San Diego, CA 92186 USA. RP Latkowski, JF (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-632, Livermore, CA 94551 USA. NR 9 TC 9 Z9 9 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 960 EP 964 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100117 ER PT J AU Smolik, GR Petti, DA Sharpe, JP Schuetz, ST AF Smolik, GR Petti, DA Sharpe, JP Schuetz, ST TI Oxidation and volatilization from tantalum alley during air exposure SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Tantalum alloys are one of the refractory metals with renewed consideration for high temperatures in fusion reactor applications. Tantalum alloys perform well in protective environments but are oxidized readily in gases containing higher oxygen levels. In addition, the radioactive isotope Ta-182 would be produced in tantalum and could be a significant contributor to dose if mobilized. Other isotopes of importance are produced from tungsten and hafnium. Mobilization of activated products during an accident with air ingress is therefore a safety issue. In this study, we measured the extent of oxidation and mobilization from tantalum alloy T-222 oxidized in flowing air between 500 and 1200 degrees C. This alloy nominally contains 10 wt% tungsten, 2.5 wt% hafnium and 0.01 wt% carbon. We found that the mobilization of Ta and Hf was closely linked to the occurrence of oxide spalling. These elements showed no migration from the test chamber. Some W was mobilized by volatilization as evidenced by transport from the chamber. Tungsten volatilization could occur primarily during initial stages of oxidation before the formation of an oxide scale impedes the process. The mobilization of Ta and W are presented in terms of the mass flux (g/m(2)-h) as a function of test temperature. These measurements along with specific designs, activation calculations, and accident scenarios provide information useful for dose calculations of future fusion devices. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Smolik, GR (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 970 EP 975 PN 2 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100119 ER PT J AU Cadwallader, LC AF Cadwallader, LC TI Qualitative reliability issues for in-vessel solid and liquid wall fusion designs SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB This paper presents the results of a study of the qualitative aspects of plasma facing component (PFC) reliability for actively cooled solid wall and liquid wall concepts for magnetic fusion reactor vessels. These two designs have been analyzed for component failure modes. The most important results of that study are given here. A brief discussion of reliability growth in design is included to illustrate how solid wall designs have begun as workable designs and have evolved over time to become more optimized designs with better longevity. The increase in tolerable heat fluxes shows the improvement. Liquid walls could also have reliability growth if the designs had similar development efforts. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Cadwallader, LC (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. RI Cadwallader, Lee/F-6933-2014 NR 15 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 991 EP 995 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100123 ER PT J AU Sanz, J Cabellos, O Yuste, P Reyes, S Latkowski, JF AF Sanz, J Cabellos, O Yuste, P Reyes, S Latkowski, JF TI Pulsed activation modeling for chamber materials of IFE power reactors and experimental facilities SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UT SP Amer Nucl Soc ID NEUTRON-ACTIVATION; IRRADIATION; EXTRACTION; CODE AB Inertial confinement fusion (ICF) devices, both test/experimental facilities and fusion energy (IFE) power plants, will operate in a pulsed mode. However, the pulsing schedule in these devices is very different, and it could range from one shot every several days in an experimental facility to some Hz in IFE reactors. The main objective of the present work is to determine whether or not a continuous-pulsed (CP) approach could be an accurate and practical methodology in modeling the pulsed activation experienced by chamber materials of both types of devices. In testing the applicability of the CP irradiation model, we used materials and neutron environment scenarios of the HYLIFE-II reactor and the NIF experimental facility. It is demonstrated that a CP approach consisting of a continuous irradiation period followed by a series of only a few pulses prior to shutdown, can efficiently model the real pulsed operating regimes of the chamber materials, in terms of both accuracy and CPU time consumption. Pros and cons of the model when compared with an equivalent steady-state (ESS) method are discussed, and comparison with the exact pulsed (EP) modeling is also performed. C1 Univ Nacl Educ Distancia, ETS Ingn Ind, Dpt Power Engn, Madrid 28040, Spain. Lawrence Livermore Natl Lab, Inst Fus Nucl, Livermore, CA 94550 USA. RP Sanz, J (reprint author), Univ Nacl Educ Distancia, ETS Ingn Ind, Dpt Power Engn, Madrid 28040, Spain. NR 15 TC 1 Z9 1 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 996 EP 1002 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100124 ER PT J AU del Rio, JG Sanz, J Reyes, S Latkowski, JF AF del Rio, JG Sanz, J Reyes, S Latkowski, JF TI Parametric study of accident consequences from different weather conditions. Application to IFE power plants SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UT SP Amer Nucl Soc AB Estimating radiological risks is an essential part of an assessment of fusion as an attractive source of energy. Due to the limited data specific to radionuclides of interest to fusion reactors, one of the goals of this work is to expand the Dose Conversion Factors (DCF) library for use in the calculation of different types of off-site doses and associated health effect consequences. This expansion accounts for about 300 radionuclides included in accidental activity releases from HYLIFE-II and SOMBRERO IFE Power Plants. Furthermore, for each of the radionuclides included in the new DCF library, we address a parametric study of accident consequences by varying the atmospheric stability, wind speed, rain conditions, and thermal plume rise. The results of these calculations allow us to identify the most troublesome radionuclides in terms of safety consequences as well as the impact of the different atmospheric scenarios. C1 Univ Nacl Educ Distancia, ETS Ingn Ind, Dpto Ingn Energet, Madrid 28040, Spain. Inst Fus Nucl, Madrid, Spain. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP del Rio, JG (reprint author), Univ Nacl Educ Distancia, ETS Ingn Ind, Dpto Ingn Energet, C Ciudad Univ S-N, Madrid 28040, Spain. NR 14 TC 4 Z9 4 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 1008 EP 1012 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100126 ER PT J AU Sharpe, JP Chappuis, P Petti, DA AF Sharpe, JP Chappuis, P Petti, DA TI Characterization of tokamak dust collected from Tore Supra SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID FUSION AB Tokamak dust, the particulate matter generated during operation of a tokamak fusion device, was collected from Tore Supra in December 1999, during the initial phase of the scheduled shutdown for installation of advanced plasma facing components. Surface mass densities of material collected from locations with measured surface area are 1100 mg/m(2) at the vessel bottom and 15 mg/m(2) on average for all other locations. The specific surface area of dust collected from several locations is nearly uniform with an average value of 1.32 g/m(2). Geometric mean diameters of samples from different locations have an average value of 3.0 mum, although geometric standard deviations vary from 1.93 to 4.03. The dust is composed of various quantities of carbon, iron, nickel, silicon, and chromium, among other trace elements. C1 Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID USA. CEA Cadarache, Assoc Euratom, DRFC, SIPP, F-13108 St Paul Durance, France. RP Sharpe, JP (reprint author), Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID USA. NR 5 TC 11 Z9 11 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 1061 EP 1065 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100136 ER PT J AU Sharpe, JP Carmack, WJ Petti, DA AF Sharpe, JP Carmack, WJ Petti, DA TI Characterization of dust and debris collected from the Nova facility SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Dust and debris were collected from the Nova laser facility in April 1999 to provide evidence of particulate generation and transport mechanisms relevant to fusion power safety analyses. Samples were obtained at specified locations within the Nova chamber with a vacuum filter system, cascade impactors, and metallurgical replicating tape (acetate tape). Average surface mass density of material collected from locations with measured surface area ranges from 3.13 mug/cm(2) on the mid-plane vertical surface to 3250 mug/cm(2) on the vessel bottom. Estimated total dust inventory is 44 grams. Specific surface area of dust collected from several locations is nearly uniform with an average value of 0.435 m(2)/g. Particle size distributions of the collected material show a range of count median diameters (CMD) between 0.67 and 1.19 mum with geometric standard deviations (GSD) between 1.63 and 2.76. Mass median diameters for dust collected with the two cascade impactors are 5.26 mum and 8.85 mum. The shape of the volumetric size distribution indicates dust particles of various shapes. Composition analysis performed by energy dispersive X-ray analysis indicated the presence of O, Al, Cu, along with trace quantities of Fe, Au, and Be. Atomic emission ICP analysis also indicated the presence of Si, O, and Cu in dust samples. C1 Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID USA. BWX Technol Inc, Lynchburg, VA 24505 USA. RP Sharpe, JP (reprint author), Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID USA. NR 3 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 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 1066 EP 1070 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100137 ER PT J AU Strand, PI Houlberg, WA AF Strand, PI Houlberg, WA TI Solution techniques for magnetic flux evolution in toroidal plasmas SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc ID DIFFUSION AB The magnetic flux evolution problem in toroidal plasmas is formulated in a framework suitable for integrating externally imposed magnetic field components with internal components from bootstrap current and auxiliary current drive. The formulation is applicable to 3-dimensional (3-D) stellarator equilibria, and reduces to 2-D form for axissymmetric plasmas. Here the numerical implementation of this framework is described. Conservative integrations schemes, resolution close to the magnetic axis, and efficient methods for flux surface averaging are discussed. Results from the test code THRIFT (THRee dimensional Inductive Flux evolution in Toroidal plasmas) are used to illustrate numerical convergence properties for a low aspect ratio stellarator and the axisymmetric NSTX spherical torus. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Strand, PI (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 1091 EP 1095 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100141 ER PT J AU Ponce, D Callis, RW Cary, WP Condon, M Grunloh, HJ Gorelov, Y Legg, RA Lohr, J O'Neill, RC Cool, R Demers, Y Raftopoulos, S AF Ponce, D Callis, RW Cary, WP Condon, M Grunloh, HJ Gorelov, Y Legg, RA Lohr, J O'Neill, RC Cool, R Demers, Y Raftopoulos, S TI Design and performance of the 110 GHz electron cyclotron heating installation on the DIII-D tokamak SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB The 110 GHz Electron Cyclotron Heating System on the DIII-D tokamak is being upgraded by the installation of additional gyrotrons, versatile launchers, and an improved control system. A total of six gyrotrons in the 1 MW class will be available for experiments during the 2001 experimental campaign. The installation will be described and the operational experience to date will be presented. C1 Gen Atom Co, San Diego, CA 92138 USA. Ctr canadien Fus Magnet, Quebec City, PQ, Canada. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Ponce, D (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92138 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 1121 EP 1125 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100147 ER PT J AU Tsai, CC Barber, GC Fadnek, A Milora, SL Ryan, PM Rasmussen, DA Sparks, DO Schechter, DE Stirling, WL AF Tsai, CC Barber, GC Fadnek, A Milora, SL Ryan, PM Rasmussen, DA Sparks, DO Schechter, DE Stirling, WL TI Indirectly heated cathode development for long-pulse neutral beam injectors SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Record beta and density values have been obtained at the Small Tight Aspect Ratio Tokamak in the United Kingdom Atomic Energy Agency (UKAEA) Fusion Culham Science Centre by using Oak Ridge National Laboratory's (ORNL's) neutral beam injector for plasma heating. This result has improved the prospects for a future spherical tokamak(ST) fusion core device. To address the physics issues of ST plasmas and the technology of neutral beam heating, ORNL neutral beam injectors have been installed on;he Mega Amp Spherical Tokamak (MAST) at UKAEA Culham. The goal of the injectors is to provide a neutral beam heating power of 5 MW for 0.5 s, or up to 4 MW for 5 s. To achieve 5-s operation at the required power level of 4 MW, the existing oxide-filament cathode must be replaced with a cathode having long-pulse capability. In 1983 ORNL developed an advanced positive ion source having long-pulse capability for 50-A and 80-keV hydrogen ion beams. The indirectly heated cathode technology developed for the advanced positive ion source will be utilized to fulfill requirements of long-pulse neutral beam heating on MAST plasmas. The cathode utilizes an electron emitter made of lanthanum oxide (La2O3) doped molybdenum. The cathode is heated by a graphite heater and insulated by a heat shield. The heat shield is made of multiple layers of tantalum sheet. Details of design and performance of such long-pulse cathodes are reported and discussed. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Lockheed Martin Energy Syst, Ten Mile, TN 37880 USA. Stirling Technol Inc, Oak Ridge, TN 37830 USA. RP Tsai, CC (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 1130 EP 1134 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100149 ER PT J AU Umeda, N Akino, N Ebisawa, N Grisham, L Hikita, S Honda, A Itoh, T Kawai, M Kazawa, M Kusaka, M Kusanagi, N Kuriyama, M Lee, P Mogaki, K Ohga, T Oohara, H Satoh, F Seki, H Seki, N Tanai, Y Toyokawa, R Usui, K Yamazaki, H AF Umeda, N Akino, N Ebisawa, N Grisham, L Hikita, S Honda, A Itoh, T Kawai, M Kazawa, M Kusaka, M Kusanagi, N Kuriyama, M Lee, P Mogaki, K Ohga, T Oohara, H Satoh, F Seki, H Seki, N Tanai, Y Toyokawa, R Usui, K Yamazaki, H TI Development of negative ion based NBI system for JT-60U SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 14th Topical Meeting on the Technology of Fusion Energy CY OCT 15-19, 2000 CL PARK CITY, UTAH SP Amer Nucl Soc AB Development for enhancing the beam characteristics in the N-NBI system for JT-60U has been continued since 1996. In order to increase beam power and duration time, a few countermeasures for improvement of source plasma non-uniformity have been tried. The first is changing are current limiting resistors for changing are current distribution, the second is regulating filament temperature for altering an: discharge mode, the third is optimizing a magnetic barrier in an: chamber, and the fourth is blocking the beam acceleration at a strongly non-uniform source plasma area by masking both upper and lower edge of plasma grid AU of these countermeasures have been confirmed to be effective. C1 Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 3110193, Japan. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Umeda, N (reprint author), Japan Atom Energy Res Inst, Naka Fus Res Estab, 801-1 Mukouyama, Naka, Ibaraki 3110193, Japan. NR 3 TC 4 Z9 4 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAR PY 2001 VL 39 IS 2 BP 1135 EP 1139 PN 2 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 418XF UT WOS:000167919100150 ER PT J AU Rickert, M Nagel, K AF Rickert, M Nagel, K TI Dynamic traffic assignment on parallel computers in TRANSIMS SO FUTURE GENERATION COMPUTER SYSTEMS LA English DT Article; Proceedings Paper CT 2nd International Conference on Web-Based Modeling and Simulation (Websim99) CY JAN 17-19, 1999 CL SAN FRANCISCO, CALIFORNIA SP Soc Comp Simulat Int DE traffic simulation; parallel computing; dynamic traffic assignment ID SIMULATION AB We describe part of the framework of the TRANSIMS traffic research project at the Los Alamos National Laboratory. It includes parallel implementations of a route planner and of a microscopic traffic simulation, and iterative re-planning for dynamic route assignment. The parallel implementation uses domain decomposition and an adaptive load-balancing scheme. We present performance figures for street networks with up to 20 000 links, and estimates for much larger networks, as will be used for the next TRANSIMS case study. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Santa Fe Inst, Santa Fe, NM USA. RP Nagel, K (reprint author), ETH Zentrum, DINFK, CH-8092 Zurich, Switzerland. NR 22 TC 24 Z9 26 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-739X J9 FUTURE GENER COMP SY JI Futur. Gener. Comp. Syst. PD MAR PY 2001 VL 17 IS 5 BP 637 EP 648 DI 10.1016/S0167-739X(00)00032-7 PG 12 WC Computer Science, Theory & Methods SC Computer Science GA 418HL UT WOS:000167884800012 ER PT J AU Wu, Q Zhang, T Cheng, JF Kim, Y Grimwood, J Schmutz, J Dickson, M Noonan, JP Zhang, MQ Myers, RM Maniatis, T AF Wu, Q Zhang, T Cheng, JF Kim, Y Grimwood, J Schmutz, J Dickson, M Noonan, JP Zhang, MQ Myers, RM Maniatis, T TI Comparative DNA sequence analysis of mouse and human protocadherin gene clusters SO GENOME RESEARCH LA English DT Article ID CADHERIN SUPERFAMILY; CPG ISLANDS; GENOMIC ORGANIZATION; OL-PROTOCADHERIN; DIVERSITY; ADHESION; REGION; FAMILY; IDENTIFICATION; EMBRYOS AB The genomic organization of the human protocadherin alpha, beta, and gamma gene clusters (designated Pcdh alpha [gene symbol PCDHA], Pcdh beta [PCDHB], and Pcdh gamma [PCDHG]) is remarkably similar to that of immunoglobulin and T-cell receptor genes. The extracellular and transmembrane domains of each protocadherin protein are encoded by an unusually large "variable" region exon, while the intracellular domains are encoded by three small "constant" region exons located downstream from a tandem array of variable region exons. Here we report the results of a comparative DNA sequence analysis of the orthologous human (750 kb) and mouse (900 kb) protocadherin gene clusters. The organization of Pcdh alpha and Pcdh gamma gene clusters in the two species is virtually identical, whereas the mouse Pcdh beta gene cluster is larger and contains more genes than the human Pcdh beta gene cluster. We identified conserved DNA sequences upstream of the variable region exons, and found that these sequences are more conserved between orthologs than between paralogs. Within this region, there is a highly conserved DNA sequence motif located at about the same position upstream of the translation start codon of each variable region exon. In addition, the variable region of each gene cluster contains a rich array of CpG islands, whose location corresponds to the position of each variable region exon. These observations are consistent with the proposal that the expression of each variable region exon is regulated by a distinct promoter, which is highly conserved between orthologous variable region exons in mouse and human. C1 Harvard Univ, Dept Mol & Cellular Biol, Cambridge, MA 02138 USA. Cold Spring Harbor Lab, Cold Spring Harbor, NY 11724 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Genome Sci Dept, Berkeley, CA 94720 USA. Stanford Univ, Sch Med, Dept Genet, Stanford, CA 94305 USA. Stanford Univ, Sch Med, Stanford Human Genome Ctr, Stanford, CA 94305 USA. RP Maniatis, T (reprint author), Harvard Univ, Dept Mol & Cellular Biol, Cambridge, MA 02138 USA. RI Wu, Qiang/A-6751-2009 OI Wu, Qiang/0000-0003-3841-3591 FU NHGRI NIH HHS [HG01696, R01 HG001696]; NIGMS NIH HHS [GM42231, R01 GM042231] NR 41 TC 149 Z9 163 U1 0 U2 7 PU COLD SPRING HARBOR LAB PRESS PI PLAINVIEW PA 1 BUNGTOWN RD, PLAINVIEW, NY 11724 USA SN 1088-9051 J9 GENOME RES JI Genome Res. PD MAR PY 2001 VL 11 IS 3 BP 389 EP 404 DI 10.1101/gr.167301 PG 16 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity GA 407DG UT WOS:000167255700009 PM 11230163 ER PT J AU Scorilas, A Kyriakopoulou, L Yousef, GM Ashworth, LK Kwamie, A Diamandis, EP AF Scorilas, A Kyriakopoulou, L Yousef, GM Ashworth, LK Kwamie, A Diamandis, EP TI Molecular cloning, physical mapping, and expression analysis of a novel gene, BCL2L12, encoding a proline-rich protein with a highly conserved BH2 domain of the Bcl-2 family SO GENOMICS LA English DT Article ID SRC HOMOLOGY-3 DOMAINS; SH3 DOMAINS; CELL-DEATH; APOPTOSIS; ACTIVATION; SEQUENCES; MUTATIONS; SURVIVAL; DISTINCT; BINDING AB Members of the Bcl-2 family of apoptosis-regulating proteins contain at least one of the four evolutionarily conserved domains, termed BH1, BH2, BH3, or BH4, Here, we report the identification, cloning, physical mapping, and expression pattern of BCL2L12, a novel gene that encodes a BCL2-like proline-rich protein. Proline-rich sites have been shown to interact with Src homology region 3 (SH3) domains of several tyrosine kinases, mediating their oncogenic potential. This new gene maps to chromosome 19q13.3 and is located between the IRF3 and the PRMT1/HRMT1L2 genes, close to the RRAS gene. BCL2L12 is composed of seven coding exons and six intervening introns, spanning a genomic area of 8.8 kb, All of the exon-intron splice sites conform to the consensus sequence for eukaryotic splice sites. The BCL2L12 protein is composed of 334 amino acids, with a calculated molecular mass of 36.8 kDa and an isoelectric point of 9.45, The BCL2L12 protein contains one BH2 homology domain, one proline-rich region similar to the TC21 protein and, five consensus PXXP tetrapeptide sequences. BCL2L12 is expressed mainly in breast, thymus, prostate, fetal liver, colon, placenta, pancreas, small intestine, spinal cord, kidney, and bone marrow and to a lesser extent in many other tissues. We also identified one splice variant of BCL2L12 that is primarily expressed in skeletal muscle. (C) 2001 Academic Press. C1 Mt Sinai Hosp, Dept Pathol & Lab Med, Toronto, ON M5G 1X5, Canada. Univ Toronto, Dept Lab Med & Pathobiol, Toronto, ON M5G 1X5, Canada. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Diamandis, EP (reprint author), Mt Sinai Hosp, Dept Pathol & Lab Med, 600 Univ Ave, Toronto, ON M5G 1X5, Canada. OI Diamandis, Eleftherios/0000-0002-1589-820X NR 19 TC 59 Z9 63 U1 1 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD MAR 1 PY 2001 VL 72 IS 2 BP 217 EP 221 DI 10.1006/geno.2000.6455 PG 5 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 417TK UT WOS:000167850100013 PM 11401436 ER PT J AU Perry, FV Valentine, GA Desmarais, EK WoldeGabriel, G AF Perry, FV Valentine, GA Desmarais, EK WoldeGabriel, G TI Probabilistic assessment of volcanic hazard to radioactive waste repositories in Japan: Intersection by a dike from a nearby composite volcano SO GEOLOGY LA English DT Article DE geologic hazards; dikes; volcanology; radioactive waste repositories; Monte Carlo analysis; probability ID EMPLACEMENT; ORIENTATION AB Geologic hazards such as volcanism must be assessed when evaluating potential sites for the geologic disposal of high-level radioactive waste. The Japanese islands comprise one of the more volcanically active regions on Earth and the risk of volcanism to a geologic repository is being evaluated as part of the Japanese high-level radioactive waste-disposal program, One hazard that is being evaluated as part of volcanic risk assessment is the possible intersection of a repository by a dike, if a composite volcano were to form near a repository during the long (100 k.y.) performance period of the repository. In this paper we use the characteristics of a well-exposed radial dike system at the Summer Goon volcano in Colorado to define Monte Carlo simulations that estimate the probability of a dike intersection of a repository as a function of volcano distance, dike length and density, and repository area. The models indicate that the probability of intersection declines rapidly as a function of distance from a volcano, as dike density decreases due to the radial dike geometry. The probability of intersection for a mafic dike set with shorter average length declines more rapidly than that of a silicic dike set with longer average length. However, mafic dikes have a higher probability of intersecting a repository close to a volcano (<5-6 km) because they are more numerous than longer silicic dikes. The probability of a silicic dike intersecting a repository is 10(-2) at distances greater than 15 km from the volcano, decreasing to less than or equal to 10(-4) at distances greater than 30 km. C1 Univ Calif Los Alamos Natl Lab, Integrated Geosci Grp EES13, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Geoanal Grp EES13, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Geol & Geochem Grp EES13, Los Alamos, NM 87545 USA. RP Perry, FV (reprint author), Univ Calif Los Alamos Natl Lab, Integrated Geosci Grp EES13, Mail Stop J521, Los Alamos, NM 87545 USA. NR 11 TC 10 Z9 10 U1 0 U2 1 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD MAR PY 2001 VL 29 IS 3 BP 255 EP 258 DI 10.1130/0091-7613(2001)029<0255:PAOVHT>2.0.CO;2 PG 4 WC Geology SC Geology GA 405WU UT WOS:000167184200016 ER PT J AU Dobrzhinetskaya, LF Green, HW Mitchell, TE Dickerson, RM AF Dobrzhinetskaya, LF Green, HW Mitchell, TE Dickerson, RM TI Metamorphic diamonds: Mechanism of growth and inclusion of oxides SO GEOLOGY LA English DT Article DE diamonds; inclusions; oxides; eskolaite; magnesite; mechanism; crystal growth ID KOKCHETAV MASSIF; NORTHERN KAZAKSTAN; ROCKS; MICRODIAMONDS AB We report a detailed series of electron microscope observations of metamorphic microdiamonds included in and separated from garnets and zircons from a single specimen of garnet-biotite-feldspar gneiss from the Kokchetav massif, Kazakhstan. The morphology of the diamonds ranges from skeletal forms composed of thin {111} plates through cuboid and octahedral forms. Included within the diamonds is a diverse suite of nanometric oxides, suggesting that the C-O-H fluid from which the diamonds grew may have carried chemical components derived from both the sediments and the mantle. The spectrum of morphologies and their abundant tiny inclusions can all be explained by a simple model based on the ratio of the rate at which {111} plates grow and the rate of random nucleation of new plates at their edges. C1 Univ Calif Riverside, Inst Geophys & Planetary Phys, Riverside, CA 92521 USA. Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RP Dobrzhinetskaya, LF (reprint author), Univ Calif Riverside, Inst Geophys & Planetary Phys, Riverside, CA 92521 USA. NR 17 TC 49 Z9 53 U1 1 U2 5 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD MAR PY 2001 VL 29 IS 3 BP 263 EP 266 DI 10.1130/0091-7613(2001)029<0263:MDMOGA>2.0.CO;2 PG 4 WC Geology SC Geology GA 405WU UT WOS:000167184200018 ER PT J AU Mulligan, T Russell, CT Elliott, D Gosling, JT Luhmann, JG AF Mulligan, T Russell, CT Elliott, D Gosling, JT Luhmann, JG TI Inversion studies of magnetic cloud structure at 0.7 AU: Solar cycle variation SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CORONAL MASS EJECTIONS; EVOLUTION; FIELDS; REGION AB Pioneer Venus observations from 1979-1988 have revealed the solar cycle evolution of magnetic clouds in the inner heliosphere. Non-force-free magnetic rope models, fit to 44 magnetic clouds, allow us to determine the structures of these clouds and compare their properties with potential field maps of their solar source regions. The leading magnetic polarity in these clouds is correlated with the polarity of the sun's global field. The axis of symmetry of the clouds varies with the inclination of the magnetic streamer belt. At 0.72 AU, the median radius of a magnetic flux rope is 0.10 AU. The median rope contains 11 TWb and carries 0.5 GAmps of parallel electric current. The occurrence frequency of different handedness of the ropes is equally left and right throughout the solar cycle and shows no correlation with other modeled parameters. C1 Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90096 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RP Mulligan, T (reprint author), Univ Calif Los Angeles, Inst Geophys & Planetary Phys, 405 Hilgard Ave, Los Angeles, CA 90096 USA. NR 22 TC 10 Z9 10 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 1 PY 2001 VL 28 IS 5 BP 891 EP 894 DI 10.1029/2000GL012016 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 406RV UT WOS:000167229700037 ER PT J AU Neagu, E Gary, SP Borovsky, JE Baumjohann, W Treumann, RA AF Neagu, E Gary, SP Borovsky, JE Baumjohann, W Treumann, RA TI Constraints on magnetic fluctuation energies in the plasma sheet SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID NEAR-EARTH MAGNETOTAIL; LOW-FREQUENCY WAVES; BOUNDARY-LAYER; ANISOTROPY INSTABILITY; NEUTRAL SHEET; DISTANT TAIL; SOLAR-WIND; ION; FLOWS; SIMULATIONS AB Magnetic field and plasma observations from magnetotail passes of the AMPTE/IRM satellite are used to study the low-frequency magnetic fluctuation energy density as a function of several local plasma parameters. Two statistical constraints on this quantity are found, one a function of proton pressure, one a function of proton flow speed, suggesting that ion-driven electromagnetic instabilities may contribute to the observed fluctuations. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Max Planck Inst Extraterr Phys, Garching, Germany. RP Neagu, E (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Baumjohann, Wolfgang/A-1012-2010 OI Baumjohann, Wolfgang/0000-0001-6271-0110 NR 27 TC 10 Z9 10 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 1 PY 2001 VL 28 IS 5 BP 919 EP 922 DI 10.1029/2000GL012384 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 406RV UT WOS:000167229700044 ER PT J AU Phillips, GW Share, GH King, SE August, RA Tylka, AJ Adams, JH Panasyuk, MI Nymmik, RA Kuzhevskij, BM Kulikauskas, VS Zhuravlev, DA Smith, AR Hurley, DL McDonald, RJ AF Phillips, GW Share, GH King, SE August, RA Tylka, AJ Adams, JH Panasyuk, MI Nymmik, RA Kuzhevskij, BM Kulikauskas, VS Zhuravlev, DA Smith, AR Hurley, DL McDonald, RJ TI Correlation of upper-atmospheric Be-7 with solar energetic particle events SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ISOTOPE SPECTROMETER; SPACECRAFT; SUN AB A surprisingly large concentration of radioactive Be-7 was observed in the upper atmosphere at altitudes above 320 km on the LDEF satellite that was recovered in January 1990. We report on follow-up experiments on Russian spacecraft at altitudes of 167 to 370 km during the period of 1996 to 1999, specifically designed to measure Be-7 concentrations in low earth orbit. Our data show a significant correlation between the Be-7 concentration and the solar energetic proton fluence at Earth, but not with the overall solar activity. During periods of low solar proton fluence, the concentration is correlated with the galactic cosmic ray fluence. This indicates that spallation of atmospheric N by both solar energetic particles and cosmic rays is the primary source of Be-7 in the ionosphere. C1 USN, Res Lab, Washington, DC 20375 USA. Moscow MV Lomonosov State Univ, Skobeltsyn Inst Nucl Phys, Moscow 119899, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Phillips, GW (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Panasyuk, Mikhail/E-2005-2012; Tylka, Allan/G-9592-2014 NR 16 TC 10 Z9 10 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 1 PY 2001 VL 28 IS 5 BP 939 EP 942 DI 10.1029/2000GL012518 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 406RV UT WOS:000167229700049 ER PT J AU Hurd, AJ Steinberg, L AF Hurd, AJ Steinberg, L TI The physics of evaporation-induced assembly of sol-gel materials SO GRANULAR MATTER LA English DT Article; Proceedings Paper CT Workshop of the Consortium of the Americas on Interdisciplinary Science on Sparsely Connected Systems: Porous and Granular Materials CY MAR 14-17, 2000 CL SAN CARLOS BARILO, ARGENTINA DE sol-gel processing; micelles; surfactants; evaporation AB Remarkable materials ordered at the nanoscale emerge when a sol-gel solution becomes co-organized with a surfactant. At sufficiently high concentration, the surfactant forms crystalline or liquid-crystalline arrays of micelles in the presence of the sol-gel, and as gelation proceeds the arrays become locked into the gel. Recent experiments demonstrate that the degree of order in the resulting mesoporous ceramic phase can be enhanced and controlled by continuous dip coating in which the solution, initially dilute, evolves through the critical micelle concentration by steady-state evaporation. The long-range order and microstructural orientation in these films suggest that the propagation of a critical-micelle-concentration transition front, with large physico-chemical gradients, promotes oriented self assembly of surfactant aggregates. This "steep-gradient" view is supported by results from unsteady evaporation of aerosols of similar solutions, in which internally well-ordered but complex particles are formed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Puerto Rico, Dept Math, Mayaguez, PR 00681 USA. RP Hurd, AJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 5 TC 6 Z9 6 U1 1 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-5021 J9 GRANUL MATTER JI Granul. Matter PD MAR PY 2001 VL 3 IS 1-2 BP 19 EP 21 DI 10.1007/s100350000060 PG 3 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied SC Materials Science; Mechanics; Physics GA 414EX UT WOS:000167654000004 ER PT J AU Sen, S Manciu, M Sinkovits, RS Hurd, AJ AF Sen, S Manciu, M Sinkovits, RS Hurd, AJ TI Nonlinear acoustics in granular assemblies SO GRANULAR MATTER LA English DT Article; Proceedings Paper CT Workshop of the Consortium of the Americas on Interdisciplinary Science on Sparsely Connected Systems: Porous and Granular Materials CY MAR 14-17, 2000 CL SAN CARLOS BARILO, ARGENTINA DE nonlinear acoustics; granular materials; solitary waves ID SOLITON-LIKE PULSES; HERTZIAN CHAINS; QUARTZ BEADS; PROPAGATION; CONTACT; BACKSCATTERING; PREDICTION; DYNAMICS; VELOCITY; COLUMNS AB We present a brief review of the problem of acoustic propagation in granular media and discuss recent progress on nonlinear acoustics in granular media. The presentation emphasizes the solitary wave like properties of impulse propagation in granular media at vanishingly small loading conditions and discusses the possible spectroscopic applications of nonlinear impulse acoustics in the detection of buried inclusions. C1 SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA. San Diego Supercomp Ctr, San Diego, CA 92186 USA. Sandia Natl Labs, Dept 1841, Albuquerque, NM 87185 USA. RP Sen, S (reprint author), SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA. RI Manciu, Marian/C-7247-2017 OI Manciu, Marian/0000-0003-4821-4131 NR 48 TC 16 Z9 15 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-5021 J9 GRANUL MATTER JI Granul. Matter PD MAR PY 2001 VL 3 IS 1-2 BP 33 EP 39 PG 7 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied SC Materials Science; Mechanics; Physics GA 414EX UT WOS:000167654000007 ER PT J AU Monetti, R Hurd, A Kenkre, VM AF Monetti, R Hurd, A Kenkre, VM TI Simulations for dynamics of granular mixtures in a rotating drum SO GRANULAR MATTER LA English DT Article; Proceedings Paper CT Workshop of the Consortium of the Americas on Interdisciplinary Science on Sparsely Connected Systems: Porous and Granular Materials CY MAR 14-17, 2000 CL SAN CARLOS BARILO, ARGENTINA DE granular matter; pattern formation; segregation ID SEGREGATION AB We present a simple model and carry out simulations to investigate the dynamics of mixtures of granular material within a rotating drum. On the basis of the commonly held belief (supported by considerable experimental evidence) that segregation is due to motion of particles on the active layer, the bulk playing little or no role, we introduce a 2d lattice gas model which takes into account the rotational frequency, frictional forces, and the gravitational field, and represents segregation tendencies via activated effective grain-grain interactions. Our results include the onset of segregation perpendicular to the drum axis, the appearance and subsequent coarsening of bands and peculiarities of the effects of periodic modulation of the drum. Observed effects such as the segregation of rougher (smoother) particles into the bellies (necks) of the modulation are reproduced by our simulation. C1 INIFTA, RA-1900 La Plata, Argentina. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Dept Phys & Astron, Ctr Adv Studies, Albuquerque, NM 87131 USA. RP Monetti, R (reprint author), INIFTA, CC 16 Suc 4, RA-1900 La Plata, Argentina. NR 19 TC 6 Z9 6 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-5021 J9 GRANUL MATTER JI Granul. Matter PD MAR PY 2001 VL 3 IS 1-2 BP 113 EP 116 PG 4 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied SC Materials Science; Mechanics; Physics GA 414EX UT WOS:000167654000022 ER PT J AU Vidales, AM Kenkre, VM Hurd, A AF Vidales, AM Kenkre, VM Hurd, A TI Simulation of Granular Compacts in two dimensions SO GRANULAR MATTER LA English DT Article; Proceedings Paper CT Workshop of the Consortium of the Americas on Interdisciplinary Science on Sparsely Connected Systems: Porous and Granular Materials CY MAR 14-17, 2000 CL SAN CARLOS BARILO, ARGENTINA DE granular matter; packing; shaking ID STRESS TRANSMISSION; MODEL; PACKINGS; PILE AB Simulations of granular packings in 2-D by throwing disks in a rectangular die are performed. Different size distributions as bimodal, uniform and gaussian are used. Once the array of particles is done, a relaxation process is carried on using a large-amplitude, low-frequency vertical shaking. This relaxation is performed a number N of times. Then, we measure the density of the package, contact distribution, coordination number distribution, entropy and also the disks size distribution vs. height. The dependence of all these magnitudes on the number N of "shakings" used to relax the packing and on the size distribution parameters are explored and discussed. C1 Univ Nacl San Luis, Dept Fis, RA-5700 San Luis, Argentina. Univ Nacl San Luis, CONICET, RA-5700 San Luis, Argentina. Univ New Mexico, Dept Phys & Astron, Ctr Adv Studies, Albuquerque, NM 87131 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Vidales, AM (reprint author), Univ Nacl San Luis, Dept Fis, RA-5700 San Luis, Argentina. NR 10 TC 3 Z9 3 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-5021 J9 GRANUL MATTER JI Granul. Matter PD MAR PY 2001 VL 3 IS 1-2 BP 141 EP 144 DI 10.1007/s100350000084 PG 4 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied SC Materials Science; Mechanics; Physics GA 414EX UT WOS:000167654000028 ER PT J AU Scheibe, TD Chien, YJ Radtke, JS AF Scheibe, TD Chien, YJ Radtke, JS TI Use of quantitative models to design microbial transport experiments in a sandy aquifer SO GROUND WATER LA English DT Article ID GROUNDWATER SOLUTE TRANSPORT; NATURAL GRADIENT EXPERIMENT; TRACER TEST; CAPE-COD; PARAMETER-ESTIMATION; SPATIAL MOMENTS; SAMPLING DESIGN; POROUS-MEDIA; MASSACHUSETTS; MOVEMENT AB A suite of numerical models was applied to the problem of designing field tracer and bacterial injection experiments in a sandy surficial aquifer near Oyster, Virginia. The models were constructed based on the integration of diverse characterization data including hydrologic, geophysical, geological, geochemical, and biological information. A one-dimensional particle-tracking model was used to analyze laboratory transport experiments conducted using intact core samples to prescribe transport parameters describing solute dispersion and bacterial fate. A geostatistical model of three-dimensional hydraulic conductivity variations was developed, conditioned on in situ measurements of hydraulic conductivity and interpretations of geophysical data, and used to generate alternative aquifer descriptions. A regional-scale, two-dimensional flow model was used to design pumping rates of a forced-gradient hydraulic control system. Information from these various models was then combined into a high-resolution, three-dimensional flow and transport model for the prediction of field-scale solute and bacterial transport. Model predictions were used in an iterative experimental design process to specify: (1) the locations of multilevel samplers for monitoring transport; (2) frequency and timing of sample collection during bromide tracer injection experiments; and (3) frequency and timing of sample collection during a bacterial injection experiment. At each stage of the design, information gained during the previous stage was used to refine the model and target subsequent experimentation. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Golder Associates Inc, Atlanta, GA 30341 USA. RP Scheibe, TD (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. RI Scheibe, Timothy/A-8788-2008 OI Scheibe, Timothy/0000-0002-8864-5772 NR 39 TC 24 Z9 24 U1 1 U2 7 PU GROUND WATER PUBLISHING CO PI WESTERVILLE PA 601 DEMPSEY RD, WESTERVILLE, OH 43081 USA SN 0017-467X J9 GROUND WATER JI Ground Water PD MAR-APR PY 2001 VL 39 IS 2 BP 210 EP 222 DI 10.1111/j.1745-6584.2001.tb02302.x PG 13 WC Geosciences, Multidisciplinary; Water Resources SC Geology; Water Resources GA 408LY UT WOS:000167328700010 PM 11286068 ER PT J AU Kramer, GH Loesch, RM Olsen, PC AF Kramer, GH Loesch, RM Olsen, PC TI The second international in-vivo monitoring intercomparison program for whole body counting facilities by Canadian and United States agencies SO HEALTH PHYSICS LA English DT Article DE calibration; reference man; phantom; whole body counting AB The Canadian National Calibration Reference Centre for In-Vivo Monitoring and the United States Department of Energy collaborated to offer a second international in vivo intercomparison program to whole body counting facilities in 1996. This program used a Reference Female phantom shell filled with radioactive tissue-substitute polyurethane to simulate a uniform fission-product distribution in soft tissues. The nuclides used were Cs-137 and Co-60. The phantom also contained K-40 homogeneously distributed in an amount similar to a Reference Female to produce a representative Compton background in the resulting spectra. Participants were asked to identify the nuclides and report activities for all except K-40. They were also asked to measure the precision of counting and supply the MDA for Cs-137 and Co-60. The bias results were in the range of -30% to +80% with most facilities falling inside the range of -25% to +50% (Canadian and U.S. acceptable performance criteria). Results indicated that there was no measurable size dependency for this phantom. All reported precisions were less than 5% but NaI detector based systems seemed to have a systematic uncertainty in addition to Poisson variability. Contrarily, this was not found for Ge detector based systems. MDA data was scattered (14-3,500 Bq for Cs-137 and 9-460 Bq for Co-60) and only suggested that lengthening the counting time improves MDA. Health Phys. 80(3):214-224; 2001. C1 Radiat Protect Bur, Human Monitoring Lab, Ottawa, ON K1A 1C1, Canada. US DOE, Off Hlth, Washington, DC 20585 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. EM Gary_H_Kramer@hc-sc.gc.ca NR 6 TC 5 Z9 5 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD MAR PY 2001 VL 80 IS 3 BP 214 EP 224 DI 10.1097/00004032-200103000-00003 PG 11 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 401YN UT WOS:000166956900003 PM 11219533 ER PT J AU Graf, T Caffee, MW Marti, K Nishiizumi, K Ponganis, KV AF Graf, T Caffee, MW Marti, K Nishiizumi, K Ponganis, KV TI Dating collisional events: Cl-36-Ar-36 exposure ages of H-chondritic metals SO ICARUS LA English DT Article DE exposure age; cosmogenic nuclides; collisional event; orbital evolution; thermal history ID RAY-PRODUCED NUCLIDES; COSMOGENIC NUCLIDES; IRON-METEORITES; HISTORY; FIREBALLS; RECORDS; MODEL; FE AB A large fraction of the H chondrites (similar to 45%) have exposure ages around 7 Ma, presumably the time at which a large collision produced numerous fragments that were subsequently placed in Earth-crossing orbits, Although this exposure age peak is observed for all petrographic types, the maxima observed among subtypes H3-H6 differ. The fall time ratios of H5 chondrites do not show the excess of afternoon falls relative to morning falls that is typical for all other ordinary chondrites, indicating that a subgroup of the H5's experienced a distinct orbital evolution. We report results of Cl-36- Ar-36 exposure ages obtained for metal separates of 6 H4 and 10 H5 chondrites with reported bulk exposure ages between 4 and 10 Ma; all the H4's selected are afternoon falls, while the H5's are morning falls. If there is structure in the similar to7-Ma event, this selection was expected to give a maximum resolution. Cl-36-Ar-36 exposure ages of H4 p.m. falls show a cluster at similar to7.6 Ma, while a wider cluster at similar to7.1 Ma is found for the H5 a,m, falls, However, when we increase the database by including recent precise Ne ages, the H4 p,m. falls define a peak at 7.6 +/- 0.2 Ma, while a shifted peak for the H5 a,m. falls is observed at 7.0 +/- 0.2 Ma. The distribution of cosmic-ray-produced He-3/Ar-38 ratios is bimodal with two clusters at similar to 15 and similar to9, the latter apparently due to solar heating effects and a quasi-continuous H-3 diffusion loss from metal, H-3 loss is significantly more frequent among H5 a,m. falls, consistent with the interpretation that a subgroup of H5 chondrites experienced a distinct orbital evolution, The "anomalous" H5 group may represent a small surviving tail of fragments that were directly injected into a resonance after a collision 7.0 Ma ago. (C) 2001 Academic Press. C1 Univ Calif San Diego, Dept Chem & Biochem, La Jolla, CA 92093 USA. Univ Calif Lawrence Livermore Natl Lab, Geosci & Environm Technol Div, Livermore, CA 94551 USA. Univ Calif San Diego, Dept Chem & Biochem, La Jolla, CA 92093 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RP Graf, T (reprint author), Univ Calif San Diego, Dept Chem & Biochem, La Jolla, CA 92093 USA. EM tgraf@pharma.unizh.ch RI Caffee, Marc/K-7025-2015 OI Caffee, Marc/0000-0002-6846-8967 NR 33 TC 12 Z9 12 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAR PY 2001 VL 150 IS 1 BP 181 EP 188 DI 10.1006/icar.2000.6560 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 421NY UT WOS:000168071500014 ER PT J AU Chang, PC Li, NY Baca, AG Hou, HQ Monier, C Laroche, JR Ren, F Pearton, SJ AF Chang, PC Li, NY Baca, AG Hou, HQ Monier, C Laroche, JR Ren, F Pearton, SJ TI Device characteristics of the GaAs/InGaAsN/GaAs p-n-p double heterojunction bipolar transistor SO IEEE ELECTRON DEVICE LETTERS LA English DT Article DE aluminum-free emitter; complementary HBT; InGaAsN; low-power electronic; p-n-p HBT ID LASER-DIODES AB We have demonstrated the de and rf characteristics of a novel p-n-p GaAs/InGaAsN/GaAs double heterojunction bipolar transistor. This device has near ideal current-voltage (I-V) characteristics with a current gain greater than 45. The smaller bandgap energy of the InGaAsN base has led to a device turn-on voltage that is 0.27 V lower than in a comparable pn-p AlGaAs/GaAs heterojunction bipolar transistor. This device has shown f(T) and f(MAX) values of 12 GHz, In addition, the aluminum-free emitter structure eliminates issues typically associated with AlGaAs. C1 Sandia Natl Labs, Albuquerque, NM 87123 USA. RP Chang, PC (reprint author), Sandia Natl Labs, Albuquerque, NM 87123 USA. NR 7 TC 10 Z9 11 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0741-3106 J9 IEEE ELECTR DEVICE L JI IEEE Electron Device Lett. PD MAR PY 2001 VL 22 IS 3 BP 113 EP 115 DI 10.1109/55.910612 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 408KE UT WOS:000167324700002 ER PT J AU Luine, JA Klushin, AM Kresin, VZ AF Luine, JA Klushin, AM Kresin, VZ TI YBa2Cu3O7-delta bicrystal grain boundary T-c microstructure SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE high temperature superconductors; Josephson devices; superconducting films AB We use an SalphaSbetaISbetaSalpha tunneling/proximity-effect model with measured YBa2Cu3O7-delta (YBCO) grain boundary junction (GBJ) normalized critical current temperature dependence eta (T) = I-c(T)/I-c(0) to infer microstructural transition temperature profiles T-c(x) for bicrystal GBJs with various misorientation angles theta, We discuss the rationale for selecting an optimum value for a numerical analysis parameter e (associated with the S,SB interface T, discontinuity). We determine the extent to which inferred T,Gr) profiles vary with +/- 20% rms deviations from nominal values for the fixed input parameters whose a priori values are not precisely known. This sensitivity analysis shows that specified T,locations can be determined with less than or equal to +/-l nm precision for T-c < 60 K, Finally, we present new inferred T-c(x) profiles for bicrystal junctions with = 24 degrees and 32 degrees and compare these profiles with those of bicrystal JJs with theta = 19 degrees and 36.8 degrees which we previously reported. Our inferred T,(x) profiles for these junctions exhibit a clear correlation with theta: as theta increases so does the extent of the grain boundary region with suppressed T-c. This expected result gives us confidence that our approach should prove useful as a tool for elucidating the structure and properties of high temperature superconductors. C1 TRW Space & Elect Grp, Redondo Beach, CA 90278 USA. Forschungszentrum Julich GmbH, Inst Schicht & Ionentech, Julich, Germany. Lawrence Berkeley Lab, Berkeley, CA USA. RP Luine, JA (reprint author), TRW Space & Elect Grp, 1 Space Pk, Redondo Beach, CA 90278 USA. NR 4 TC 0 Z9 0 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 426 EP 429 DI 10.1109/77.919374 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400093 ER PT J AU Yoon, J Clarke, J Gildemeister, JM Lee, AT Richards, PL AF Yoon, J Clarke, J Gildemeister, JM Lee, AT Richards, PL TI AC voltage-biased superconducting bolometer for a frequency-domain SQUID multiplexer SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE multiplexer; voltage-biased superconducting bolometer (VSB); SQUID; bolometer ID STRONG ELECTROTHERMAL FEEDBACK AB We demonstrate that a voltage-biased superconducting bolometer (VSB), read out with a superconducting quantum interference device (SQUID), can be biased with a sinusoidal voltage. We show that the load curves taken with AC- and DC-bias are nearly identical indicating that there is no identifiable degradation in the performance of the bolometer due to the AC bias. We discuss the use of a frequency-domain SQUID multiplexer with an array of VSB's that are AC-biased. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Phys, Berkeley, CA 94720 USA. RP Yoon, J (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 9 TC 3 Z9 3 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 562 EP 565 DI 10.1109/77.919407 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400126 ER PT J AU Ullom, JN van den Berg, ML Labov, SE AF Ullom, JN van den Berg, ML Labov, SE TI A new idea for a solid-state microrefrigerator operating near 100 mK SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE microrefrigeration; normal-insulator-superconductor tunnel junctions; tunneling ID TUNNEL JUNCTION AB We propose a new design for solid-state microrefrigerator based on Normal-Insulator-Superconductor (NIS) tunnel junctions. These devices are a promising means of providing continuous refrigeration from 0.3 to 0.1 K without vibration or moving parts. Previously, the area and cooling power of NIS refrigerators have been limited by heating of the superconducting electrode. This problem can be overcome by using a superconducting single crystal as both the substrate and superconducting electrode of the NIS junction. In this paper, we briefly explain the benefits of our new design and describe experimental progress towards building such a device. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Ullom, JN (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 8 TC 3 Z9 3 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 639 EP 640 DI 10.1109/77.919425 PN 1 PG 2 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400144 ER PT J AU Chow, DT van den Berg, ML Loshak, A Frank, M Barbee, TW Labov, SE AF Chow, DT van den Berg, ML Loshak, A Frank, M Barbee, TW Labov, SE TI Gamma-ray spectrometers using superconducting transition edge sensors with external active feedback bias SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE cryogenic detectors; microcalorimeters; transition-edge sensors; bulk absorbers; active feedback bias ID ELECTROTHERMAL FEEDBACK; DETECTORS AB We are developing x-ray and gamma-ray spectrometers with high absorption efficiency and high energy-resolution for x-ray and gamma-ray spectroscopy. They are microcalorimeters consisting of a bulk Sn absorber coupled to a Mo/Cu multilayer superconducting transition edge sensor (TES), We have operated these microcalorimeters with an external active feedback bias to linearize the detector response, improve the count rate performance, and extend the detection energy range, We measured an energy resolution of 120 eV FWHM for 60 keV incident gamma-rays with no degradation of resolution from active bias, We present x-ray and gamma-ray results and operation of this detector design in both bias modes. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. RP Chow, DT (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Frank, Matthias/O-9055-2014 NR 11 TC 4 Z9 4 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 743 EP 746 DI 10.1109/77.919452 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400171 ER PT J AU Friedrich, S Hiller, LJ Cunningham, MF Labov, SE AF Friedrich, S Hiller, LJ Cunningham, MF Labov, SE TI Line-splitting in high-resolution superconducting tunnel junction EUV detectors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE energy relaxation; EUV detectors; line shapes; superconducting tunnel junctions ID X-RAY SPECTROMETERS; QUASIPARTICLE; NIOBIUM; ENERGY; PERFORMANCE; FILMS AB We have developed high-resolution Nb-Al-AlOx-Al-Nb tunnel junction extreme ultra-violet (EUV) detectors. In the energy range between 25 and 70 eV, we have measured an energy resolution of 2.2 eV full-width at half maximum (FWHM), The energy resolution degrades significantly in the energy range between approximate to 80 and approximate to 230 eV where the Mb absorber is partially transparent and some of the photons are absorbed in the Al trap layers. We have for the first time observed a distinctly different response for photons absorbed in the Nh and the Al layer of the same junction electrode, We have modeled this effect with Monte-Carlo simulations of the charge generation process in superconducting multilayers. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Adv Detector Grp, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Lawrence Livermore Natl Lab, Adv Detector Grp, Livermore, CA 94551 USA. RP Friedrich, S (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Adv Detector Grp, MS 6-2100, Berkeley, CA 94720 USA. NR 20 TC 4 Z9 4 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 836 EP 839 DI 10.1109/77.919474 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400193 ER PT J AU Matlashov, A Espy, M Kraus, RH Ganther, KR Snapp, LD AF Matlashov, A Espy, M Kraus, RH Ganther, KR Snapp, LD TI Electronic gradiometer using HTc SQUIDS with fast feedback electronics SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VA DE biomagnetism; high slew rate SQUID readout; non-destructive evaluation; superconducting gradiometer ID FLUX TRANSFORMER; MAGNETOMETER AB An electronic gradiometer was built using a HTS SQUID magnetometer array. A SQUID magnetometer in the center of the array was used to pick up background noise, and the output signal fed back to other magnetometers to cancel background noise. Fast feedback electronics were built for the background channel with a slew rate about 10(7) phi (0)/sec and 10 MHz small signal bandwidth, Two other magnetometers of the array were connected to pcSQUID (TM) electronics with 5x10(4) phi (0)/sec slew rate using the AC bias mode to decrease l/f noise. The output signals from these two magnetometers were input to a summing amplifier resulting in a gradiometric output signal without background channel noise. Constructing the gradiometer with different magnetometers on the array enables us to vary the baseline from 0.75 mm to 7.5 mm with 2x10(-12) T/root Hz field resolution in an unshielded laboratory environment, This variable-baseline gradiometer can be used for NDE, biomagnetism and other applications. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Hneywell fed Mfg & Technol, Kansas City, MO 64141 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM matlachov@lanl.gov; espy@lanl.gov; rkraus@lanl.gov; kganther@kcp.com; lsnapp@kcp.com NR 16 TC 5 Z9 5 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 876 EP 879 DI 10.1109/77.919484 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400203 ER PT J AU Espy, MA Matlashov, AN Mosher, JC Kraus, RH AF Espy, MA Matlashov, AN Mosher, JC Kraus, RH TI Non-destructive evaluation with a linear array of 11 HTS SQUIDs SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE high-temperature superconductor; SQUIDs; non-destructive testing; eddy currents AB A linear array of 11 High Temperature Superconducting (HTS) SQUIDs was used for non-destructive evaluation (NDE) applications, The array consists of 11 SQUID magnetometers arranged linearly along a single substrate with 0.75 mm spacing, The SQUIDs have 105 nT/Phi (0) field sensitivity and < 20 mu Phi (0)/root Hz noise values at 1 KHz with DC bias current. We used an eddy current NDE technique. The eddy current induction coils were arranged such that there was a null in the induction field at the SQUIDs, Single frequency and white-noise (frequency-continuum) induction schemes were used. Both SQUIDs and induction coils were placed at the bottom of a liquid nitrogen dewar with a 4 mm hot-to-cold distance. Flawed and unflawed samples were scanned beneath the array. The phase and amplitude of the SQUID's response relative to the induction signal were acquired. This paper presents experimental results and their interpretation. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Espy, MA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 2 TC 5 Z9 5 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1303 EP 1306 DI 10.1109/77.919589 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400306 ER PT J AU Clatterbuck, DM Lee, TK Shaw, TJ Heinig, NF Cho, HM Clarke, J Morris, JW AF Clatterbuck, DM Lee, TK Shaw, TJ Heinig, NF Cho, HM Clarke, J Morris, JW TI Detection of plastic deformation gradients in steel using scanning SQUID microscopy SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE hardness; magnetic properties; plastic deformation; SQUIDS; steel AB Scanning SQUID microscopy is shown to be capable of detecting deformation gradients when accompanied by significant changes in hardness, Deformation which does not increase the dislocation density las measured by the increase in hardness) has little effect. The effect can be produced by different techniques including cold rolling and tensile deformation, The effect is shown to occur in at least two different alloys with very different microstructures indicating the possibility of wide applicability. C1 Lawrence Berkeley Natl Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Clatterbuck, DM (reprint author), Lawrence Berkeley Natl Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. NR 12 TC 8 Z9 8 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1307 EP 1310 DI 10.1109/77.919590 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400307 ER PT J AU Green, MA Bangerter, RO AF Green, MA Bangerter, RO TI Magnet and cryostat configurations for a multi-port quadrupole array SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VA DE quadrupole array and cryostat AB This report describes the results of a study of arrays of up to sixteen quadrupoles in a single cryostat surrounded by an induction accelerator that is used for accelerating high current heavy ion beams for fusion, Each quadrupole in the array can have a gradient of 72 T/m, when the quadrupole has a warm bore diameter of 90 mm, An array of sixteen quadrupoles can be made to fit into a round cryostat vacuum vessel with a diameter of 850 mm, If the number of quadrupoles in the array is reduced to nine, the outer diameter of the cryostat is 700 mm. It is proposed that the quadrupole array be conduction cooled using either a 4 K cryocooler or two phase liquid helium in pipes around the magnet array. The two-phase helium can be supplied to a string of multi-bore quadrupoles using a large refrigerator. C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Green, MA (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 9 TC 2 Z9 2 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1502 EP 1505 DI 10.1109/77.920060 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600014 ER PT J AU Martovetsky, NN Manahan, RR AF Martovetsky, NN Manahan, RR TI Focusing magnets for HIF based on racetracks SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE quadrupole; racetrack winding; gradient; harmonics ID HEAVY-ION FUSION; DESIGN; DIPOLE AB Heavy Ion Fusion (HIF) is considered a promising path to a practical fusion reactor. A driver for a HIF reactor will require a large number of quadrupole arrays to focus heavy ion beams. A conceptual design, and trade off studies of the quadrupole array based on racetracks are presented. A comparison with a conventional shell magnet is given and advantages and disadvantages are discussed. A more detailed design of a single quadrupole for the High Current eXperiment (HCX) is presented and discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Martovetsky, NN (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 5508, Livermore, CA 94550 USA. NR 7 TC 6 Z9 6 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1506 EP 1509 DI 10.1109/77.920061 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600015 ER PT J AU Parker, B Anerella, M Escallier, J Ghosh, A Jain, A Marone, A Muratore, J Prodell, A Thompson, P Wanderer, P Wu, KC AF Parker, B Anerella, M Escallier, J Ghosh, A Jain, A Marone, A Muratore, J Prodell, A Thompson, P Wanderer, P Wu, KC TI HERA luminosity upgrade superconducting magnet production at BNL SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE accelerator magnets; computer controlled winding; dipole; luminosity upgrade; superconducting cable; quadrupole AB Production of two types of superconducting multi-function magnets, needed for the HERA Luminosity Upgrade is underway at BNL. Coil winding is now completed and cryostat assembly is in progress. Magnet type GO and type GG cold masses have been satisfactorily cold tested in vertical dewars and the first fully assembled GO magnet system has been horizontally cold tested and shipped to DESY. Warm measurements confirm that the coils meet challenging harmonic content targets. In this paper we discuss GO and GG magnet design and construction solutions, field harmonic measurements and quench test results. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Parker, B (reprint author), Brookhaven Natl Lab, Bldg 902A, Upton, NY 11973 USA. NR 5 TC 5 Z9 5 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1518 EP 1521 DI 10.1109/77.920064 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600018 ER PT J AU Waynert, JA Schultz, J Thome, RJ Myatt, L Kimball, FM Baldi, RW AF Waynert, JA Schultz, J Thome, RJ Myatt, L Kimball, FM Baldi, RW TI Cost scaling analysis of large warm-bore superconducting quadrupoles SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VA DE saccelerator lens magnets; quadrupoles; superconducting magnets; superconductivity AB This paper presents an approach to estimating the cost of large warm-bore superconducting quadrupoles that are frequently used in magnetic imaging systems in accelerators. Quadrupole magnet radial apertures greater than about 10 cm and gradients exceeding 10 T/m are considered. A relationship is established so that the cost estimate may be scaled with the gradient, aperture, and length of the magnet. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. MIT, Cambridge, MA 02139 USA. Myatt Consulting Inc, Norfolk, VA USA. Foster M Kimball Consultants, San Diego, CA 92124 USA. Gen Atom, San Diego, CA 92121 USA. RP Waynert, JA (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM waynert@lanl.gov; jhs@psfc.mit.edu; thome@psfc.mit.edu; lmyatt@earthlink.net; fkimball@san.rr.com; bob.baldi@gat.com NR 3 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1522 EP 1525 DI 10.1109/77.920065 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600019 ER PT J AU Andreev, N Arkan, T Bauer, P Bossert, R Brandt, J Carson, J Caspi, S Chichili, DR Chiesa, L Darve, C Dimarco, J Feher, S Ghosh, A Glass, H Huang, Y Kerby, J Lamm, M Markarov, AA McInturff, AD Nicol, T Nobrega, A Novitski, I Ogitsu, T Orris, D Ozelis, JP Page, T Peterson, T Rabehl, R Robotham, W Sabbi, G Scanlan, R Schlabach, P Sylvester, C Strait, J Tartaglia, M Tompkins, JC Velev, G Yadav, S Zlobin, AV AF Andreev, N Arkan, T Bauer, P Bossert, R Brandt, J Carson, J Caspi, S Chichili, DR Chiesa, L Darve, C Dimarco, J Feher, S Ghosh, A Glass, H Huang, Y Kerby, J Lamm, M Markarov, AA McInturff, AD Nicol, T Nobrega, A Novitski, I Ogitsu, T Orris, D Ozelis, JP Page, T Peterson, T Rabehl, R Robotham, W Sabbi, G Scanlan, R Schlabach, P Sylvester, C Strait, J Tartaglia, M Tompkins, JC Velev, G Yadav, S Zlobin, AV TI Status of the LHC inner triplet quadrupole program at Fermilab SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE cryogenics; quadrupole; superconductivity AB Fermilab, in collaboration with LBNL and BNL, is developing a quadrupole for installation in the interaction region inner triplets of the LHC. This magnet is required to have an operating gradient of 215 T/m across a 70 mm coil bore, and operates in superfluid helium at 1.9 K. A 2 m magnet program addressing mechanical, magnetic, quench protection, and thermal issues associated with the design was completed earlier this year, and production of the first full length, cryostatted prototype magnet is underway. This paper summarizes the conclusions of the 2 m program, and the design and status of the first full-length prototype magnet. C1 Fermilab, Batavia, IL 60510 USA. Jefferson Lab, Newport News, VA USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. KEK, Tsukuba, Ibaraki, Japan. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Andreev, N (reprint author), Fermilab, POB 500, Batavia, IL 60510 USA. NR 5 TC 12 Z9 12 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1558 EP 1561 DI 10.1109/77.920074 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600028 ER PT J AU Andreev, N Arkan, T Bauer, P Bossert, R Brandt, J Caspi, S Chichili, DR Carson, J DiMarco, J Feher, S Ghosh, A Glass, H Kashikhin, VV Kerby, J Lamm, MJ McInturff, AD Makarov, AA Nobrega, A Novitski, I Ogitsu, T Orris, D Ozelis, JP Peterson, T Rabehl, R Robotham, W Sabbi, G Scanlan, R Schlabach, P Sylvester, C Strait, J Tartaglia, M Tompkins, JC Velev, G Yadav, S Zlobin, AV AF Andreev, N Arkan, T Bauer, P Bossert, R Brandt, J Caspi, S Chichili, DR Carson, J DiMarco, J Feher, S Ghosh, A Glass, H Kashikhin, VV Kerby, J Lamm, MJ McInturff, AD Makarov, AA Nobrega, A Novitski, I Ogitsu, T Orris, D Ozelis, JP Peterson, T Rabehl, R Robotham, W Sabbi, G Scanlan, R Schlabach, P Sylvester, C Strait, J Tartaglia, M Tompkins, JC Velev, G Yadav, S Zlobin, AV TI Field quality in Fermilab-built models of quadrupole magnets for the LHC interaction region SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE magnetic fields; quadrupole; superconductivity AB Superconducting quadrupole magnets for the interaction regions of the Large Hadron Collider are being developed by the US-LHC Accelerator Project. These 70 mm bore quadrupole magnets are intended to operate in superfluid helium at 1.9 K with a nominal field gradient of 215 T/m. A series of 2 m model magnets has been built and cold tested at Fermilab to optimize their design and construction and to study the performance of the magnets. Field measurements of the 8 model magnets and comparisons with the required field quality are reported in this paper. C1 Fermilab, Batavia, IL 60510 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. Brookhaven Natl Lab, Upton, NY 11973 USA. KEK, Tsukuba, Ibaraki, Japan. Jefferson Lab, Newport News, VA USA. RP Andreev, N (reprint author), Fermilab, POB 500, Batavia, IL 60510 USA. NR 8 TC 2 Z9 2 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1566 EP 1569 DI 10.1109/77.920076 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600030 ER PT J AU Brindza, P Gavalya, A Lassiter, S LeRose, J Cisabni, E Frullani, S Garibaldi, F Iodice, M Urciuoli, G Nilles, M AF Brindza, P Gavalya, A Lassiter, S LeRose, J Cisabni, E Frullani, S Garibaldi, F Iodice, M Urciuoli, G Nilles, M TI Superconducting septum magnet design for Jefferson Lab Hall A SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE detector magnets; septum magnets; cold iron magnets AB A pair of Superconducting Septum Magnets are required to permit Hypernuclear Physics Experiments at JLAB's Hall A at angles to the incident beam as small as 6 degrees. A Cold Iron Superconducting " C " magnet design has been selected. This magnet has a central field of 4.23 Tesla at a current density of 25,000 Amp/cm2, the stored energy is 0.22 Megajoules and the inductance is 1.0 Henries. The magnet has an effective field length of 0.67 meters, an average gap of 0.25 meters and an average pole width of 0.15 meters. The magnet is currently being fabricated by BWXT Inc. under contract to INFN. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Ist Nazl Fis Nucl, Rome, Italy. BWX Technol Inc, Lynchburg, VA 24505 USA. RP Brindza, P (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. NR 2 TC 5 Z9 5 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1594 EP 1596 DI 10.1109/77.920083 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600037 ER PT J AU Bauer, P Chiesa, L Feher, S Kerby, J Lamm, M Orris, D Sylvester, C Tompkins, JC Zlobin, AV AF Bauer, P Chiesa, L Feher, S Kerby, J Lamm, M Orris, D Sylvester, C Tompkins, JC Zlobin, AV TI Busbar studies for the LHC interaction region quadrupoles SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE accelerator; superconducting magnet AB Fermilab (FNAL) and the Japanese high energy physics lab (KEK) are developing the superconducting quadrupole magnets for the interaction regions (IR) of the Large Hadron Collider (LHC). These magnets have a nominal field gradient of 215T/m in a 70mm bore and operate in superfluid helium at 1.9K. The IR magnets are electrically interconnected with superconducting busbars, which need to be protected in the event of a quench. Experiments to determine the most suitable busbar design for the LHC IR magnets and the analysis of the data are presented. The main purpose of the study was to find a design that allows the inclusion of the superconducting busbars in the magnet quench protection scheme, thus avoiding additional quench protection circuitry. A proposed busbar design that was tested in these experiments consists of a superconducting cable, which is normally used for the inner layer of the Fermilab IR quadrupoles, soldered to similar Rutherford type cables as a stabilizer. A series of prototypes with varying numbers and types of stabilizers (one or two stabilizers, pure copper or Cu/NbTi composite) were tested. These samples were characterized with respect to their quench temperature profile and their quench propagation velocity during normal zone growth. From these tests, a suitable design has been determined. C1 Fermilab, Batavia, IL 60510 USA. RP Bauer, P (reprint author), Fermilab, Batavia, IL 60510 USA. NR 6 TC 0 Z9 0 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1613 EP 1616 DI 10.1109/77.920088 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600042 ER PT J AU Bauer, P Bossert, R Chiesa, L DiMarco, J Feher, S Lamm, MJ Mcinturff, AD Nobrega, A Orris, D Tartaglia, M Tomkpins, JC Zlobin, AV AF Bauer, P Bossert, R Chiesa, L DiMarco, J Feher, S Lamm, MJ Mcinturff, AD Nobrega, A Orris, D Tartaglia, M Tomkpins, JC Zlobin, AV TI Quench protection of the LHC inner triplet quadrupoles built at Fermilab SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE accelerator; superconducting magnet ID HIGH-GRADIENT QUADRUPOLE; INTERACTION REGIONS AB High gradient quadrupoles are being developed by the US-LHC Accelerator project for the LHC interaction region inner triplets. These 5.5 m long magnets have a single 70 mm aperture and operate in superfluid helium at a peak gradient of 215 T/m. Through the construction and test of eight 2 meter long model quadrupoles, strip heaters of various geometries and insulation thicknesses have proven to be effective in protecting the magnets from excessively high coil temperatures and coil voltages to ground. This paper reports on the results of the model program to optimize the heater performance within the context of the LHC inner triplet electrical power and quench detection scheme. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Bauer, P (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1617 EP 1620 DI 10.1109/77.920089 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600043 ER PT J AU Chiesa, L Feher, S Kerby, J Lamm, M Novitski, I Orris, D Ozelis, JP Peterson, TJ Tartaglia, M Zlobin, AV AF Chiesa, L Feher, S Kerby, J Lamm, M Novitski, I Orris, D Ozelis, JP Peterson, TJ Tartaglia, M Zlobin, AV TI Thermal studies of a high gradient quadrupole magnet cooled with pressurized, stagnant superfluid SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE cryogenics; magnet; superconductivity ID LHC INTERACTION REGIONS AB A 2-m long superconducting model of an LHC Interaction Region quadrupole magnet was wound with stabrite coated cable. The resulting low interstrand resistance and high AC losses presented the opportunity to measure magnet quench performance in superfluid as a function of helium temperature and heat deposition in the coil, Our motivation was to duplicate the high radiation heat loads predicted for the inner triplet quadrupoles at LHC and study the coil cooling conditions in the magnet. At the Magnet Test Facility in Fermilab's Technical Division, the magnet quench performance was tested as a function of bulk helium temperature and current ramp rate near the planned high luminosity interaction region field gradient of 205 T/m. AC loss measurements provided a correlation between current ramp rate and heat deposition in the coil. Analysis indicates that the results are consistent with there being little participation of superfluid helium in the small channels inside the inner layer in the heat removal from the coil. However magnet performance will be limited by the outer coil pole turn in LHC at a current level well above the operating current. C1 Fermilab, Batavia, IL 60510 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Chiesa, L (reprint author), Fermilab, POB 500, Batavia, IL 60510 USA. NR 7 TC 5 Z9 5 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1625 EP 1628 DI 10.1109/77.920091 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600045 ER PT J AU Darve, C Huang, Y Nicol, TH Peterson, TJ AF Darve, C Huang, Y Nicol, TH Peterson, TJ TI Experimental investigations of HeII heat transfer through a short section of LHC inner triplet quadrupole heat exchanger SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE heat exchanger; HeII; Kapitza; LHC AB The LHC inner triplet quadrupoles, cooled by pressurized He II, are subjected to a total heat load of more than 7 W/m at nominal luminosity, The heat absorbed in pressurized He LI will be transferred to the saturated, two-phase He II via a corrugated copper pipe. Experimental investigations of He II heat transfer across the corrugated pipe are reported, The test sample of corrugated pipe is filled with pressurized He II and with saturated He II on the outside. The maximum heat flux to the test sample is up to 145 W/m(2). The characteristics of the corrugated copper pipes under investigation are the Kapitza resistance, thermal conductivity of the material and the geometry of the pipe. The test results for a series of bath temperatures and surface treatments are included. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Darve, C (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1629 EP 1632 DI 10.1109/77.920092 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600046 ER PT J AU Andreev, N Arkan, T Bauer, P Bossert, R Brandt, J Carson, J Caspi, S Chichili, DR Chiesa, L DiMarco, J Feher, S Ghosh, A Glass, H Kerby, J Lamm, MJ Makarov, A McInturff, AD Nobrega, A Novitski, I Ogitsu, T Orris, D Ozelis, JP Peterson, T Rabehl, R Robotham, W Scanlan, R Schlabach, P Sylvester, C Strait, J Tartaglia, M Tompkins, JC Velev, G Yadav, S Zlobin, AV AF Andreev, N Arkan, T Bauer, P Bossert, R Brandt, J Carson, J Caspi, S Chichili, DR Chiesa, L DiMarco, J Feher, S Ghosh, A Glass, H Kerby, J Lamm, MJ Makarov, A McInturff, AD Nobrega, A Novitski, I Ogitsu, T Orris, D Ozelis, JP Peterson, T Rabehl, R Robotham, W Scanlan, R Schlabach, P Sylvester, C Strait, J Tartaglia, M Tompkins, JC Velev, G Yadav, S Zlobin, AV TI Quench performance of Fermilab model magnets for the LHC inner triplet quadrupoles SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE magnets; quadrupole; superconducting AB As part of the US LHC program to develop high gradient superconducting quadrupoles for the LHC interaction regions, a series of 2 meter long model magnets has been built and tested at Fermilab. This R&D program was used to refine the mechanical and magnetic design, optimize fabrication and assembly tooling and ensure adequate quench performance. The final design, fabrication, and assembly procedures developed in this program have produced magnets which meet the LHC requirements of operating at 215 T/m with excellent magnetic field harmonics. This paper summarizes the test results of the last five model magnets, including quench tests over several thermal cycles, and excitation current ramp rate and temperature dependence studies. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Thomas Jefferson Natl Accelerator Lab, Newport News, VA USA. RP Andreev, N (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1633 EP 1636 DI 10.1109/77.920093 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600047 ER PT J AU Mulcahy, TM Hull, JR Uherka, KL Abboud, RG Juna, JJ AF Mulcahy, TM Hull, JR Uherka, KL Abboud, RG Juna, JJ TI Test results of 2-kWh flywheel using passive PM and HTS bearings SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE diurnal energy storage; flywheel; passive HTS/permanent-magnet bearings; Halbach-array motor/generator; full-scale testing ID SUPERCONDUCTING MAGNETIC BEARINGS; SYSTEM AB Toward demonstrating the potential of flywheel energy storage systems that use high-temperature superconductors (HTSs) and permanent magnets (PMs) as passive rotor bearings, a flywheel system was developed and tested with a 165-kg cylindrical carbon- and glass-fiber rotor to rim speeds of 400 m/s (19,000 rpm) and stored energies of >2.25 kWh. The main bearing's internal stack of PM rings was passively stabilized by HTS bearings at each end of the rotor. The stator portion of the HTS bearing consisted of an array of melt-textured YBCO pellets bathed in liquid nitrogen inside a nonconducting cryochamber, The motor/generator (M/G) was based on an internal-dipole Halbach array and could produce 1.5 Nm of torque. Each bearing and the M/G included multipiece banded PM rings secured to the rotor inside diameter with flexible urethane rings. In a vacuum enclosure at 10(-4) Pa pressure, rotational drag on the rotor was hysteretic and at low speeds the coefficient of friction was well below 10(-6). C1 Argonne Natl Lab, Argonne, IL 60439 USA. UNICOM, Chicago, IL 60603 USA. RP Mulcahy, TM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 34 Z9 34 U1 3 U2 11 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1729 EP 1732 DI 10.1109/77.920117 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600071 ER PT J AU Lue, JW Barber, GC Demko, JA Gouge, MJ Stovall, JP Hughey, RL Sinha, UK AF Lue, JW Barber, GC Demko, JA Gouge, MJ Stovall, JP Hughey, RL Sinha, UK TI Fault current tests of a 5-m HTS cable SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE critical current; current limitation; fault current; high temperature superconducting cable AB The first industrial demonstration of a three-phase, BTS power transmission cable at the Southwire manufacturing complex is in progress, One crucial issue during operation of the 30-m HTS cables is whether they can survive the fault current (which can he over an order of magnitude higher than the operating current) in the event of a short circuit fault and how HTS cables and the cryogenic system would respond, Simulated fault-current tests were performed at ORNL on a 5-m cable, This single-phase cable was constructed in the same way as the 30-m cables and is also rated for 1250 A at 7.3 kV ac line-to-ground voltage. Tests were performed with fault-current pulses of up to 15 kA (for 0.5 s) with pulse lengths of up to 5 s (at 6.8 kA). Although a large voltage drop was produced across the HFS cable during the fault-current purse, no significant changes in the coolant temperature, pressure, or joint resistance were observed. The cable survived all 15 simulated fault-current shots without any degradation in its V-I characteristics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Southwire Co, Carrollton, GA 30119 USA. RP Lue, JW (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 4 TC 18 Z9 18 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1785 EP 1788 DI 10.1109/77.920132 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600085 ER PT J AU Demko, JA Lue, JW Gouge, MJ Stovall, JP Butterworth, Z Sinha, U Hughey, RL AF Demko, JA Lue, JW Gouge, MJ Stovall, JP Butterworth, Z Sinha, U Hughey, RL TI Practical AC loss and thermal considerations for HTS power transmission cable systems SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE cryogenic; high-temperature superconductivity; power-transmission lines AB The use of high-temperature superconducting materials for power-transmission cable applications is being realized in prototype situations. It is well known that ac loss decreases as the temperature of the conductor decreases. Also, thermal losses are higher at lower temperatures, owing to the increased temperature difference between ambient and cryogenic operating conditions. Both counterflow and parallel-flow cooling arrangements have been proposed in the literature and significantly affect temperature distribution along the cable. In this investigation, the counteracting ac loss and thermal losses are analyzed for both cooling configurations to determine the benefits and limits of each. The thermal-insulation performance levels of materials versus those of typical systems in operation are presented. Widespread application of long length flexible cable systems, from the refrigeration paint of view, mill depend on an energy-efficient cryogenic system that is economical to manufacture and operate. While the counterflow arrangement will typically have a lower heat load, it has a length ii mit arising from the large pressure drop associated with the configuration. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Southwire Co, Carrollton, GA 30119 USA. RP Demko, JA (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 7 TC 22 Z9 28 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1789 EP 1792 DI 10.1109/77.920133 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600086 ER PT J AU Halbritter, J Kneisel, P Palmieri, V Pekeler, M AF Halbritter, J Kneisel, P Palmieri, V Pekeler, M TI Electric surface resistance R-E(T, f, E-perpendicular to) of Nb/Nb2O5-y-interfaces and Q-drop of superconducting Nb cavities SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE superconducting Nb cavities; surface resistance; field dependencies ID WEAK LINKS; IMPEDANCE; NIOBIUM; CUPRATE AB The rf losses, especially actual level and increase with rf fields limit most stringently the application of superconducting rf cavities. This is due to the needed cooling power to he supplied locally to the high field region and doe to the nonlinearities causing harmonics and rf breakdown, The separation of rf residual losses R-res(T,f) from the intrinsic losses R-BCS(Tf) yields the quasi-exponential increases of the electric surface resistance with the electric field E-perpendicular to perpendicular to the surface deltaR(E)(E-perpendicular to) proportional to exp (-c/E-perpendicular to) and the power law increases of the magnetic surface impedances with the magnetic field H-parallel to parallel to the surface deltaR(H)(H-parallel to) proportional to) (H-parallel to)(2n) (R = 1, 2. .). By the Nb/Nb2O5-y interfaces at external and internal surfaces R-res(H) (T,f) and R-res(E) (f, E-perpendicular to) can be explained quantitatively, Especially the drop of Q(o)(E-perpendicular to) proportional to 1/R-res(E) (E-perpendicular to) and its reduction by EP- and BCP-smoothening and qv better interfaces by UHV anneal are well accounted for by interface tunnel exchange.(1) C1 Forschungszentrum Karlsruhe, IMF 1, D-76021 Karlsruhe, Germany. TJLAB, Newport News, VA USA. Ist Nazl Fis Nucl, I-35020 Legnaro, Italy. DESY, D-22603 Hamburg, Germany. RP Halbritter, J (reprint author), Forschungszentrum Karlsruhe, IMF 1, Postfach 3640, D-76021 Karlsruhe, Germany. NR 40 TC 19 Z9 19 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1864 EP 1868 DI 10.1109/77.920212 PN 2 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600105 ER PT J AU Smith, BA Michiel, PC Minervini, JV Takayasu, M Schultz, JH Gregory, E Pyon, T Sampson, WB Ghosh, A Scanlan, R AF Smith, BA Michiel, PC Minervini, JV Takayasu, M Schultz, JH Gregory, E Pyon, T Sampson, WB Ghosh, A Scanlan, R TI Design, fabrication and test of the react and wind, Nb3Sn, LDX floating coil conductor SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE superconducting cables; superconducting coils; magnetic levitation AB The Levitated Dipole Experiment (LDX) is a novel approach for studying magnetic confinement of a fusion plasma, In this approach, a superconducting ring coil is magnetically levitated for up to 8 hours a day in the center of a 5 meter diameter vacuum vessel. The levitated coil, with onboard helium supply, is called the Floating Coil (f-Coil). Although the maximum field at the coil is only 5.3 tesla, a react-and-wind Nb3Sn conductor was selected because the relatively high critical temperature will enable the coil to remain levitated while it warms from 5 K to 10 K. Since pre-reacted Nb3Sn tape is no longer commercially available, a composite conductor was designed that contains an 18 strand Nb3Sn Rutherford cable. The cable was reacted and then soldered into a structural copper channel that completes the conductor and also provides quench protection. The strain state of the cable was continuously controlled during fabrication steps such as: soldering into the copper channel, spooling, and coil winding, to prevent degradation of the critical current, Measurements of strand and cable critical currents are reported, as well as estimates of the effect of fabrication, winding and operating strains on critical current. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Intermagnet Gen Corp, Adv Supercond, Waterbury, CT 06704 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Smith, BA (reprint author), MIT, Plasma Sci & Fus Ctr, 77 Massachusetts Ave, Cambridge, MA 02139 USA. OI Michael, Philip/0000-0003-4906-6169 NR 6 TC 6 Z9 6 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1869 EP 1872 DI 10.1109/77.920213 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600106 ER PT J AU Michael, PC Vieira, R Jayakumar, RV Kato, T Nakajima, H Sugimoto, H AF Michael, PC Vieira, R Jayakumar, RV Kato, T Nakajima, H Sugimoto, H TI Mechanical preloading of the Central Solenoid Model Coil SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE force measurement; mechanical modeling; superconducting magnets AB The inner and outer modules of the Central Solenoid Model Coil (CSMC) are mechanically compressed by a preload structure. The necessary preload is determined for the support of the modules' terminal leads. The forces in the preload structure are monitored by strain gauge bridges mounted to each of the structure's 16 inner and 16 outer tension rods during: 1) room temperature loading, 2) cool-down to the coil's operating temperature, and 3) electromagnetic operation, The preload structure is described and the variations in the preload with each stage of coil operation are presented. Analytical models are presented, which use the observed variations in preload to deduce equivalent mechanical properties for the coil modules. C1 MIT, PSFC, Cambridge, MA 02139 USA. LLNL, Livermore, CA USA. JAERI, Naka, Ibaraki, Japan. RP Michael, PC (reprint author), MIT, PSFC, 77 Massachusetts Ave, Cambridge, MA 02139 USA. OI Michael, Philip/0000-0003-4906-6169 NR 11 TC 6 Z9 6 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1877 EP 1880 DI 10.1109/77.920215 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600108 ER PT J AU Gung, CY Michael, PC Martovetsky, NN Isono, T Nunoya, Y Ando, T Okuno, K AF Gung, CY Michael, PC Martovetsky, NN Isono, T Nunoya, Y Ando, T Okuno, K TI Instrumentation of the Central Solenoid Model Coil and the CS insert SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE ITER; pulsed magnet; fusion; central solenoid; instrumentation; and sensors AB The Central solenoid Model Coil (CSMC) was built by the US rind the Japanese home teams as part of an international collaboration which also involved the European Union and Russian Federation. The CSMC and CS Insert Coil were installed at a purpose build test facility at the Japan Atomic Energy Research Institute in Naka, Japan and tested from March through August 2000, With over 500 sensors installed on the coils, bus bars, plumbing, facility and the structure, the CSMC and CS insert,were instrumented to obtain valuable data about their performances, and to reveal the qualification of the large scale superconducting solenoids for the next fusion machine. This paper describes the instrumentation inside the vacuum chamber used in various stages of the CSMC anti the CS Insert coil operation. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. ITER, Joint Cent Team, Naka, Ibaraki, Japan. RP Gung, CY (reprint author), MIT, Plasma Sci & Fus Ctr, 77 Massachusetts Ave, Cambridge, MA 02139 USA. OI Michael, Philip/0000-0003-4906-6169 NR 6 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 1881 EP 1884 DI 10.1109/77.920216 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600109 ER PT J AU Martovetsky, N Michael, P Minervini, J Radovinsky, A Takayasu, M Thome, R Ando, T Isono, T Kato, T Nakajima, H Nishijima, G Nunoya, Y Sugimoto, M Takahashi, Y Tsuji, H Bessette, D Okuno, K Ricci, M AF Martovetsky, N Michael, P Minervini, J Radovinsky, A Takayasu, M Thome, R Ando, T Isono, T Kato, T Nakajima, H Nishijima, G Nunoya, Y Sugimoto, M Takahashi, Y Tsuji, H Bessette, D Okuno, K Ricci, M TI ITER CS model coil and CS insert test results SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE critical current; losses; superconducting magnets; instability ID AC LOSS; FABRICATION; COMPLETION AB The Inner and Outer modules of the Central Solenoid Model Coil (CSMC) were built by US and Japanese home teams in collaboration with European and Russian teams to demonstrate the feasibility of a superconducting Central Solenoid for ITER and other large tokamak reactors, The CSMC mass is about 120 t, OD is about 3.6 m and the stored energy is 640 MJ at 46 kA and peak field of 13 T, Testing of the CSMC and the CS Insert took place at Japan Atomic Energy Research Institute (JAERI) from mill March until mid August 2000. This paper presents the main results of the tests performed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Japan Atom Energy Res Inst, Naka, Ibaraki, Japan. ITER, Joint Cent Team, Naka, Ibaraki, Japan. ENEA CR, Frascati, Italy. RP Martovetsky, N (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Nishijima, Gen/B-8804-2009; OI Nishijima, Gen/0000-0001-7493-0559; Michael, Philip/0000-0003-4906-6169 NR 15 TC 29 Z9 29 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2030 EP 2033 DI 10.1109/77.920253 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600146 ER PT J AU Ennis, MG Tobin, TJ Cha, YS Hull, JR AF Ennis, MG Tobin, TJ Cha, YS Hull, JR TI Fault current limiter - Predominantly resistive behavior of a BSCCO-shielded-core reactor SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE fault current limiter; magnetic diffusion; SSCR; transformer model ID SUPERCONDUCTOR TUBE AB Tests were conducted to determine the electrical and magnetic characteristics of a superconductor-shielded core reactor (SSCR), The results show that a closed-core SSCR Is predominantly a resistive device and an open-core SSCR is a hybrid resistive/inductive device. The open-core SSCR appears to dissipate less energy than the closed-core SSCR, However, the impedance of the open-core SSCR is less than that of the closed-core SSCR, Magnetic and thermal diffusion are believed to be the mechanisms that facilitate penetration of the superconductor tube under Fault conditions. C1 S&C Elect Co, Chicago, IL 60626 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Ennis, MG (reprint author), S&C Elect Co, Chicago, IL 60626 USA. NR 13 TC 8 Z9 8 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2050 EP 2053 DI 10.1109/77.920258 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600151 ER PT J AU Yamada, R Wake, M Kim, SW Wands, RH AF Yamada, R Wake, M Kim, SW Wands, RH TI Design and considerations on long Nb3Sn high field magnets for hadron colliders SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Nb3Sn high field magnet; quench simulation; long superconducting magnet; MIIT AB Design studies for long high field Nb3Sn superconducting magnets far hadron colliders are described, taking a 10 meter magnet with a cosine-theta type coil as an example, The problems and complications are discussed in comparison with short magnets of 1 meter length, using MIIT calculations and quench simulation. As the stored energy in the high field Nb3Sn magnets is quite large, close attention must be paid to all design details, and especially the extraction of the stored energy, The extensive e use of heaters on the coil surface is simulated to dump the energy on the coil body itself. The MIIT value of the Nb3Sn superconducting cable should be made large for safe operation. This is done by increasing the copper ratio, According to the results of this study, an 11.5 Tesla magnet might be the limiting case for the design of a practical accelerator high field magnet. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. KEK, High Energy Accelerator Lab, Tsukuba, Ibaraki 3050801, Japan. RP Yamada, R (reprint author), Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. NR 10 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2054 EP 2057 DI 10.1109/77.920259 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600152 ER PT J AU Kashikhin, VV Zlobin, AV AF Kashikhin, VV Zlobin, AV TI Correction of the persistent current effect in Nb3Sn dipole magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE passive corrector; persistent currents; magnetization; superconducting magnet ID DESIGN AB The paper describes a method and results of simulation of persistent current effect in high field Nb3Sn dipole magnets being developed for the future hadron colliders, Simple and effective techniques of passive correction of the persistent current effect in superconducting accelerator magnets are proposed, Using of these techniques allows a significant reduction of sextupole and decapole field components induced by persistent currents in a coil. C1 Fermi Natl Accelerator Lab, Fermilab, Batavia, IL 60510 USA. RP Kashikhin, VV (reprint author), Fermi Natl Accelerator Lab, Fermilab, POB 500,MS 316, Batavia, IL 60510 USA. NR 13 TC 21 Z9 21 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2058 EP 2061 DI 10.1109/77.920260 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600153 ER PT J AU Barzi, E Fratini, M Higley, HC Scanlan, RM Yamada, R Zlobin, AV AF Barzi, E Fratini, M Higley, HC Scanlan, RM Yamada, R Zlobin, AV TI Strand critical current degradation in Nb3Sn Rutherford cables SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE critical current degradation; Nb3Sn strand; Rutherford cable; superconducting magnet AB Fermilab is developing 11 Tesla superconducting accelerator magnets based on nb(3)Sn superconductor, Multifilamentary Nb3Sn strands produced using the Modified Jelly Roil, Internal Tin, and powder-in-Tube technologies were used for the development and test of the prototype cable. To optimize the cable geometry with respect to the critical current, short samples of Rutherford cable with packing factors In the 85 to 95% range were fabricated and studied. In this paper, the results of measurements of critical current, n-value and RRR made on the round virgin strands and on the strands extracted from the cable samples are presented. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Barzi, E (reprint author), Fermi Natl Accelerator Lab, MS 316, Batavia, IL 60510 USA. NR 4 TC 7 Z9 7 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2134 EP 2137 DI 10.1109/77.920279 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600172 ER PT J AU Scanlan, RM AF Scanlan, RM TI Conductor development for high energy physics-plans and status of the US program SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Nb3Sn; accelerator magnets AB In order to provide a cost effective high field magnet option for the nest generation HEP accelerator, higher performance Nb3Sn superconductor is required. These requirements have been recognized by the DOE, and a conductor development program has been initiated. The goal is to produce a cost-effective conductor with a Jc(noncopper,12T,4.2 K) exceeding 3000 A/mm(2) and an effective filament size of less than 40 micrometers. Although the Nb3Sn conductors manufactured at present have produced Je values in Excess of 2200 A/mm(2), no conductor being manufactured at present can achieve both the aggressive Jc and effective filament size goals. The first phase of the present program is underway, and is focused on improving the understanding of the factors that control Jc, Samples are being manufactured by industry and are being characterized with respect to Jc and magnetization as a function of composition and heat treatment condition. Using this new knowledge as a base, the program will move into a fabrication scale-up phase where the performance and cost-effectiveness can be demonstrated on production size quantities. The status and accomplishments of this program will be reviewed, and the plans for the scale-up program will he presented. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Scanlan, RM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 12 TC 41 Z9 43 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2150 EP 2155 DI 10.1109/77.920283 PN 2 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600176 ER PT J AU Sampson, WB Ghosh, AK Cozzolino, JP Harrison, MA Wanderer, PJ AF Sampson, WB Ghosh, AK Cozzolino, JP Harrison, MA Wanderer, PJ TI Persistent current effects in BSCCO common coil dipoles SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Common Coil Magnets; remnant fields; HTS BSSCO-2223 tape conductor AB A series of one-meter long racetrack-shaped windings has been fabricated from BSCCO tape conductors obtained from four manufacturers. Two coils were built from each conductor type and tested In the "common coil" dipole configuration in liquid helium. The effect of the remnant magnetization currents was determined by measuring the residual elipole and sextupole fields after cycling the magnets to progressively higher currents. Two coil sets have been measured and the results are compared to those obtained from a Nb3Sn ribbon magnet of the same geometry. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Sampson, WB (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 2 TC 2 Z9 2 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2156 EP 2159 DI 10.1109/77.920284 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600177 ER PT J AU Chichili, DR Ambrosio, G Andreev, N Barzi, E Caspi, S Kashikhin, VV Limon, PJ Scanlan, R Terechkine, I Tompkins, J Wake, M Yadav, S Yamada, R Yarba, V Zlobin, AV AF Chichili, DR Ambrosio, G Andreev, N Barzi, E Caspi, S Kashikhin, VV Limon, PJ Scanlan, R Terechkine, I Tompkins, J Wake, M Yadav, S Yamada, R Yarba, V Zlobin, AV TI Fabrication of the shell-type Nb3Sn dipole magnet at Fermilab SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Nb3Sn; dipole magnet; fabrication ID DESIGN; MODEL AB A 43.5 nun aperture dipole magnet with a nominal field of II T is being fabricated at Fermilab, The design is based on a two-layer shell-type coil structure made of Rutherford-type Nb3Sn cable with wind and react technology. The mechanical support structure consists of vertically split iron yoke locked bg two aluminum damps and a 8 mm thick stainless steel skin. This paper summarizes the fabrication details of the first dipole model and test results from a 200 mm long mechanical model. C1 Fermi Natl Accelerator Lab, Tech Div, Batavia, IL 60510 USA. LBNL, Berkeley, CA 94720 USA. Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. RP Chichili, DR (reprint author), Fermi Natl Accelerator Lab, Tech Div, POB 500, Batavia, IL 60510 USA. NR 5 TC 18 Z9 18 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2160 EP 2163 DI 10.1109/77.920285 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600178 ER PT J AU Benjegerdes, B Bish, P Byford, D Caspi, S Chow, K Dietderich, D Gourlay, SA Gupta, R Hafalia, R Hannaford, R Harnden, W Higley, H Jackson, A Lietzke, A Liggins, N McInturff, A Millos, G O'Neill, J Palmerston, E Sabbi, G Scanlan, R Swanson, J AF Benjegerdes, B Bish, P Byford, D Caspi, S Chow, K Dietderich, D Gourlay, SA Gupta, R Hafalia, R Hannaford, R Harnden, W Higley, H Jackson, A Lietzke, A Liggins, N McInturff, A Millos, G O'Neill, J Palmerston, E Sabbi, G Scanlan, R Swanson, J TI Fabrication and test of Nb3Sn racetrack coils at high field SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA AB A program based on exploring the benefits of racetrack coil designs for utilization of brittle superconductors to achieve high fields is underway at LBNL. As an intermediate step in the experimental program, a set of Nb3Sn racetrack coils, using state-of-the-art conductor, have been built and tested. The coils were configured to maximize the field, providing a means to study the effects of stress on conductor performance. In addition, several design improvements mere added which will be implemented ill the nest step of the program; construction of a racetrack dipole with a field of 14 Tesla. An evaluation of the design modifications and test results are given. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Benjegerdes, B (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 3 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2164 EP 2167 DI 10.1109/77.920286 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600179 ER PT J AU Gupta, R Anerella, M Cozzolino, J Escallier, J Ganetis, G Ghosh, A Harrison, M Morgan, G Muratore, J Parker, B Sampson, W Wanderer, P AF Gupta, R Anerella, M Cozzolino, J Escallier, J Ganetis, G Ghosh, A Harrison, M Morgan, G Muratore, J Parker, B Sampson, W Wanderer, P TI Common coil magnet program at BNL SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE accelerators; high temperature superconductors; magnets; superconducting magnets AB The goal of the common coil magnet R&D program at Brookhaven National Laboratory (BNL) is to develop a 12.5 T, 40 mm aperture dipole magnet using "React and Wind Technology'' with High Temperature Superconductors (HTS) playing a major role, Due to its "conductor friendly'' nature, the common coil design is attractive for building high field 2-in-1 dipoles with brittle materials such as HTS and Nb,Sn. At the current rate of development, it is expected that a sufficient amount of HTS with the required performance would be available in a few years for building a short magnet. In the interim, the first generation dipoles will be built with Nb3Sn superconductor. They will use a "React and Wind" technology similar to that used in HTS and will produce a 12.5 T central field in a 40 mm aperture. The Nb3Sn coils and support structure of this magnet will become a part of the next generation hybrid magnet with inner coils made of HTS, To develop various aspects of the technology in a scientific and experimental manner, a 10-turn soil program has been started in parallel, The program allows a number of concepts to be evaluated with ii rapid throughput in a cost-effective way, Three 10-turn Nb3Sn coils have been built and one HTS coil is under construction. The initial test results of this "React S: Wind" 10-turn coil program are presented, It is also shown that a common coil magnet design can produce a field quality that is as good as a conventional cosine theta design. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Gupta, R (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 9 TC 7 Z9 7 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2168 EP 2171 DI 10.1109/77.920287 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600180 ER PT J AU Ambrosio, G Andreev, N Barzi, E Bauer, P Chichili, D Ewald, K Imbasciati, L Kashikhin, V Kim, SW Limon, P Novitski, I Ozelis, JP Scanlan, R Sabbi, G Zlobin, A AF Ambrosio, G Andreev, N Barzi, E Bauer, P Chichili, D Ewald, K Imbasciati, L Kashikhin, V Kim, SW Limon, P Novitski, I Ozelis, JP Scanlan, R Sabbi, G Zlobin, A TI Development of react & wind common coil dipoles for VLHC SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE accelerator magnets; superconducting magnets; Nb3Sn; common coil dipoles AB Common coil magnets are a promising option for post LHC hadron colliders, Fermilab, in collaboration with LBNL, is involved in an R&D program to develop 11 T, 30-40 mm aperture, common coil dipoles, The use of Nb3Sn wound after reaction is chosen in order to address cost reduction that is a key issue for future hadron colliders. The common coil design concept allows a Large bending radius at the coil ends and is well suited to the react-and-wind technique with brittle superconductors, The horizontal component of the magnetic forces in a common coil is larger than the radial component in a shell type layout, imposing demanding requirements on the mechanical structure. Both a 2-layer and a single layer design have been studied, The development of the program is presented focusing on the mechanical designs and assembly techniques, R&D activities and plans are also presented. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. LBNL, Berkeley, CA 94720 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Ambrosio, G (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 12 TC 6 Z9 6 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2172 EP 2175 DI 10.1109/77.920288 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600181 ER PT J AU Kashikhin, VV Zlobin, AV AF Kashikhin, VV Zlobin, AV TI Magnetic designs of 2-in-1 Nb3Sn dipole magnets for VLHC SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE accelerator magnet; cos-theta and common coil geometry; magnetic design; superconducting cable AB The paper presents the results of a conceptual design study of double aperture Nb3Sn dipole magnets for VLHC based on the cos-theta and common coil geometry with cold and warm Iron yoke. The study included an optimization of the iron yoke geometry to achieve the maximum transfer function, smalt fringe fields and low-order field harmonics as well as an optimization of the coil geometry to correct a quadrupole field component (normal or skew) Inevitable for 2-in-1 magnet, designs. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Kashikhin, VV (reprint author), Fermi Natl Accelerator Lab, POB 500,MS-316, Batavia, IL 60510 USA. NR 8 TC 4 Z9 4 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2176 EP 2179 DI 10.1109/77.920289 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600182 ER PT J AU Green, MA Fockler, J Lafever, RE Vanecek, DL Yu, SS AF Green, MA Fockler, J Lafever, RE Vanecek, DL Yu, SS TI A thin superconducting solenoid for use in a phase rotation induction linac SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA ID MAGNET AB One of the proposals for delivering a cooled muon beam to a muon collider or a high intensity neutrino source uses an induction Linac to phase rotate the muons that result from the decay of pions produced by a high intensity proton beam on a target, An induction linac with an acceleration gradient of 2MV per meter is proposed to produce bunches of muons that have a momentum of 200 MeV/c. The induction accelerator is assembled around the 3T superconducting solenoids needed to contain the muon beam. The superconducting solenoid must have a warm 100-mm gap at 1000-mm intervals down the phase rotation channel. The acceleration structure for the induction linac is around this gap. The superconducting solenoid will have an Inside warm radius of 201 mm, The thickness of the superconducting magnet and its cryostat must be about 60 mm near the acceleration gap. An access region of 85 mm between induction linac sections is allowed for the superconducting coil cold mass supports, the electrical leads and the supply of cryogenic cooling. This report presents a design for a 3 T phase rotation induction linac superconducting magnet system, its cryostat, and its cooling system. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Green, MA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2180 EP 2183 DI 10.1109/77.920290 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600183 ER PT J AU Willis, JO Daney, DE Maley, MP Boenig, HJ Mele, R Coletta, G Nassi, M Clem, JR AF Willis, JO Daney, DE Maley, MP Boenig, HJ Mele, R Coletta, G Nassi, M Clem, JR TI Multiphase ac loss mechanisms in HTS prototype multistrand conductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE superconducting power transmission lines; alternating current losses; multiphase losses; high temperature superconductors ID CABLES AB We report on multiphase ac losses in four-layer prototype multi-strand conductors (PMCs) wound from high temperature superconductor (HTS) tape provided by American Superconductor Corporation. "Two-phase" losses are induced with no current flowing in the PMC but with all sc magnetic field generated by currents flowing in the two normal conductors arranged at the remaining corners of an equilateral triangle forming a three-phase configuration, This is a typical configuration that a pow er cable of the "warm dielectric" design could have, The losses were measured at 65 to 76 It, in a frequency range from 10 to 180 Hz, and for currents from 600 to 1600 Arms. We compare the losses for two PMCs, one wound conventionally with equal pitch angles for all levers and the second wound to achieve uniform current distribution (UCD) among the layers. The UCD method results in I educed single-phase losses at currents greater than about 1/2 of the critical current. However, the two-phase losses are somewhat larger for the PMC wound by the UCD method. We investigated this difference empirically and theoretically. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Pirelli Cavi & Sistemi, I-20126 Milan, Italy. Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames, IA 50011 USA. RP Willis, JO (reprint author), Univ Calif Los Alamos Natl Lab, MS-K763, Los Alamos, NM 87545 USA. NR 7 TC 5 Z9 5 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2188 EP 2191 DI 10.1109/77.920292 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600185 ER PT J AU Ashworth, SP Suenaga, M AF Ashworth, SP Suenaga, M TI Local calorimetry to measure the ac losses in structures of HTS conductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA ID TRANSPORT CURRENTS; MAGNETIC-FIELDS; SUPERCONDUCTORS; TAPES AB We have previously shown that it is possible to measure losses of a conductor in almost any combination of field and current using our recently developed calorimetric method, We now extend this technique to structures of conductors where the ac magnetic fields generated by the structure as a whole influence the losses of the individual conductors. Using our calorimetric technique we are able to measure the losses at specific locations within a coil or array. in this paper we present as examples loss measurements made on a simple solenoidal coil and in a multi-tape, high amperage conductor. C1 Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. RP Ashworth, SP (reprint author), Brookhaven Natl Lab, Div Mat Sci, POB 5000, Upton, NY 11973 USA. NR 10 TC 0 Z9 0 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2200 EP 2203 DI 10.1109/77.920295 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600188 ER PT J AU Caspi, S Gourlay, S Hafalia, R Lietzke, A ONeill, J Taylor, C Jackson, A AF Caspi, S Gourlay, S Hafalia, R Lietzke, A ONeill, J Taylor, C Jackson, A TI The use of pressurized bladders for stress control of superconducting magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE bladder; pressurize; stress; superconducting AB LBNL is using pressurized bladders in its high field superconducting magnet program. Magnet RD3; a 14 T race track dipole; has been assembled and pre-stressed using such a system. The bladder, plated between the coil pack and the iron yoke, can provide 70 MPa of pressure while compressing the coil pack and tensioning a 40 mm thick structural Aluminun shell, Interference keys replace the bladder's functionality as they are deflated and removed leaving the shell in 140 MPa of tension. During cool down, stress in the shell increases to 250 MPa as a result of the difference in thermal expansion between the Aluminum shell and the inner if on yoke. A number of strain gauges mounted onto the shell were used to monitor its strain during assembly cool-down and testing. This technique ensures that the anal and maximum stress in the shell is reached before the magnet is ever energized. The use of a structural shell and pressurized bladders has simplified magnet assembly considerably. In this paper we describe the bladder system and its use in the assembly of a 14T Nb3Sn magnet. C1 LBNL, Berkeley, CA 94720 USA. RP Caspi, S (reprint author), LBNL, Mail Stop 46-16, Berkeley, CA 94720 USA. NR 5 TC 45 Z9 45 U1 1 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2272 EP 2275 DI 10.1109/77.920313 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600206 ER PT J AU Novitski, I Andreev, N Ambrosio, G Bauer, P Kashikhin, VV Zlobin, AV AF Novitski, I Andreev, N Ambrosio, G Bauer, P Kashikhin, VV Zlobin, AV TI Design and mechanical analysis of a singlelayer common coil dipole for VLHC SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE common coil dipole; mechanical design; superconducting accelerator magnet AB Fermilab is developing a 2-in-1, 11 T block-type common coil dipole magnet for a future Very Large Hadron Collider. The common-coil design concept allows a large bending radius at the coil ends and therefore is well suited for use of the react-and-wind technique with. brittle superconductors. The magnet features one-layer flat Nb3Sn coil wound using pre-reacted cable, h novel mechanical design has been developed to provide effective coil support against Lorentz forces, minimize conductor displacement during excitation, reduce coil pre-load at room temperature, and prevent force accumulation, The details of the design concept and results of the mechanical analysis are presented in this paper. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Novitski, I (reprint author), Fermi Natl Accelerator Lab, MS 316, Batavia, IL 60510 USA. NR 9 TC 5 Z9 5 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2276 EP 2279 DI 10.1109/77.920314 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600207 ER PT J AU Sabbi, G Caspi, S Gourlay, SA Hafalia, R Jackson, A Lietzke, A McInturff, AD Scanlan, RM AF Sabbi, G Caspi, S Gourlay, SA Hafalia, R Jackson, A Lietzke, A McInturff, AD Scanlan, RM TI Design of racetrack coils for high-field dipole magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA ID COMMON AB The magnet group at LBNL is currently in the process of developing high-field accelerator magnets for use in future colliders. One of the primary challenges is to provide a design which is cost-effective and simple to manufacture, at the same time resulting in good training performance and field quality adequate for accelerator operation. Recent studies have focused on a racetrack geometry that has the virtues of simplicity and conductor compatibility. The results have been applied to the design of a series of prototype high-field magnets based on Nb3Sn conductor. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Sabbi, G (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 11 TC 3 Z9 3 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2280 EP 2283 DI 10.1109/77.920315 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600208 ER PT J AU Yadav, S Chichili, DR Terechkine, I AF Yadav, S Chichili, DR Terechkine, I TI Coil end parts design and fabrication issues for the high field dipole at Fermilab SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE end parts; rapid prototyping; Nb3Sn dipole magnet AB End parts are one of the most costly components of a superconducting magnet, Therefore, efforts are underway at Fernilab to develop new technologies to reduce the fabrication time and cost of the magnet end parts. In this paper, we discuss some of the design and fabrication issues for the magnet end parts with particular specific objective in mind. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Yadav, S (reprint author), Fermi Natl Accelerator Lab, POB 500,MS 316, Batavia, IL 60510 USA. NR 5 TC 2 Z9 2 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2284 EP 2287 DI 10.1109/77.920316 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600209 ER PT J AU Chichili, DR Kashikhin, VV Zlobin, AV AF Chichili, DR Kashikhin, VV Zlobin, AV TI Mechanical design and analysis of 2-in-1 shell-type Nb3Sn dipole models for VLHC SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Nb3Sn; superconducting dipole magnets; twin aperture; "cold" iron yoke; "warm" iron yoke AB Fermilab has recently begun investigating Nb3Sn twin aperture dipole magnet designs as a next step towards the realization of high field magnets for a Very Large Hadron Collider (VLHC). The magnet design is based on two-layer shell-type Nb3Sn coils with 43.5 mm aperture. Two different mechanical designs were investigated, one with "cold" iron yoke and the other with "warm" Iron yoke. The former has a vertically split three-piece iron yoke with a cut parallel to a flux line to reduce the transverse magnetic flux. The two outer halves are locked in place by aluminum clamps. Both the clamps and the stainless skin provide the required pre-stress to the coils, The "warm" iron yoke design consists of thick freestanding stainless steel collars with wide keys and an insert separating the two coil blocks. The paper presents both the mechanical design and analysis for the two designs. C1 Fermi Natl Accelerator Lab, Div Technol, Batavia, IL 60510 USA. RP Chichili, DR (reprint author), Fermi Natl Accelerator Lab, Div Technol, MS 316, Batavia, IL 60510 USA. NR 2 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2288 EP 2291 DI 10.1109/77.920317 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600210 ER PT J AU Green, MA McInturff, AD AF Green, MA McInturff, AD TI Scaling laws for modeling large superconducting solenoids SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA AB The neutrino factory cooling system will consist of a long series of superconducting solenoids with a warm bore of 1.2 meters. In order to minimize the cost of the 200 to 300-meter long solenoid muon-coeling channel, the solenoids must be fabricated so that their mass is minimized. This report discusses how one can model the stress, strain and quench behavior of these large solenoid sections by building one-third to one-half scale models of the magnets, The cost of building and engineering tire scale model magnets is a small fraction of the cost of fabricating a full-scale magnet section. This report discuses the limitations of the scaling approach as well as the types of superconducting solenoids for which the modeling technique is suitable. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Green, MA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 9 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2292 EP 2295 DI 10.1109/77.920318 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600211 ER PT J AU Green, MA Chen, JY Wang, ST AF Green, MA Chen, JY Wang, ST TI A test of a superconducting solenoid for the mucool RF experiment SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VA AB This report describes the results of a series of tests of a 440-mm warm bore split solenoid used for testing 805 MMz RF cavities, The solenoid consists of two coils each 250-mm long separated by a gap of 140 mm. The solenoid was designed to operate in two modes; a solenoid mode with the two coils hooked in the same polarity and a gradient mode with the two coils hooked in opposite polarity. In the solenoid mode, the magnet is designed to produce an induction of 5 T over a region that is about 400 mm long. In the gradient mode, the solenoid produces a field gradient of 25 T per meter along the asis over a distance of about 300-mm. The solenoid was designed to carry a force of over 3 MN that pushes the two coils apart, when the magnet is operated in the gradient mode. In order to carry this force, the coils are encased within aluminum shells, both inside and outside. Since this solenoid is encased in aluminum and the coils are potted, training was observed. The magnet training history and magnet field measurements are presented in this report. C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. Wang NMR Inc, Livermore, CA 94550 USA. RP Green, MA (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 2 TC 5 Z9 5 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2296 EP 2299 DI 10.1109/77.920319 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600212 ER PT J AU Meinke, RB Goodzeit, CL AF Meinke, RB Goodzeit, CL TI Bent superconducting solenoids with superimposed dipole fields SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE bent solenoids; muon storage rings; superconducting magnets AB Superconducting solenoid magnets with a superimposed dipole field have been proposed for the cooling channel for a future high luminosity muon collider. The magnets are typically bent into a 180 degrees are with a centerline radius of about 0.5 m and an aperture of 0.3 to 0.4 m. They are characterized by having an on-axis solenoidal field of about 4 T with a 1 T superimposed dipole field. A cost-effective design is proposed, in which the dipole field is generated by tilting the winding planes of the solenoid coil. The magnetic and mechanical design of such magnets are presented. C1 Adv Magnet Lab, Palm Bay, FL 32905 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Meinke, RB (reprint author), Adv Magnet Lab, 2730 Kirby Ave NE, Palm Bay, FL 32905 USA. NR 4 TC 3 Z9 3 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2300 EP 2303 DI 10.1109/77.920320 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600213 ER PT J AU Gouge, MJ Demko, JA Fisher, PW Foster, CA Lue, JW Stovall, JP Sinha, U Armstrong, J Hughey, RL Lindsay, D Tolbert, J AF Gouge, MJ Demko, JA Fisher, PW Foster, CA Lue, JW Stovall, JP Sinha, U Armstrong, J Hughey, RL Lindsay, D Tolbert, J TI Development and testing of HTS cables and terminations at ORNL SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE high-temperature superconductivity; power transmission lines; cryogenic terminations AB The Oak Ridge National Laboratory (ORNL) and the Southwire Company have used the ORNL 5-m cable test facility to develop high-temperature superconducting (HTS) cables and terminations to support the first industrial demonstration of an HTS cable at the Southwire manufacturing complex. Two 5-m, cold dielectric. cables have been tested for direct current (dc) voltage, alternating current (ac) losses, ac withstand at 18 kV, thermal-hydraulic performance, heat load, and long-term operation at rated voltage (7.2 kV) and current (1250 A). Two separate termination concepts, one operating at 10(-4)-10(-5) mbar vacuum and the other operating with pressurized nitrogen gas at < 10 bar, have been developed and tested with the 5-m cables, A 5-m cable has been removed from the facility and bent in a test rig to simulate transport in a spool, A testing program for a third 5-m cable with a splice is in progress, The test program at ORNL has validated the basic design of the cables and terminations and indicated areas for further R&D to optimize this technology for electric utility applications. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Southwire Co, Carrollton, GA 30119 USA. RP Gouge, MJ (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. NR 6 TC 17 Z9 18 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2351 EP 2354 DI 10.1109/77.920333 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600226 ER PT J AU Bauer, P Ambrosio, G Andreev, N Barzi, E Dietderich, D Ewald, K Fratini, M Ghosh, AK Higley, HC Kim, SW Miller, G Miller, J Ozelis, J Scanlan, RM AF Bauer, P Ambrosio, G Andreev, N Barzi, E Dietderich, D Ewald, K Fratini, M Ghosh, AK Higley, HC Kim, SW Miller, G Miller, J Ozelis, J Scanlan, RM TI Fabrication and testing of Rutherford-type cables for react and wind accelerator magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE accelerator; superconducting magnet; superconducting cable; Nb3Sn AB A common coil design for a high-field accelerator dipole magnet using a Nb3Sn cable with the React-and-Wind approach is pursued by a collaboration between Fermilab and L-BNL. The design requirements for the cable include a high operating current so that a field of 10-11 T can be produced, together with a low critical current degradation due to bending around a 90 mm radius, a program, using ITER strands of the internal tin type, was launched to develop the optimal cable design for React-and-Wind common coil magnets. Three prototype cable designs, all 15 mm wide, were fabricated: a 41-strand cable with 0.7 mm diameter strands; a 57-strand cable with 0,5 mm diameter strands; and a 259-strand multi-level cable with a 6-around-1 sub element using 0.3 mm diameter wire. Two versions of these cables were fabricated: one with no core and one with a stainless steel core. Additionally, the possibility of a wide (22 mm) cable made from 0.7 mm strand was explored. This paper describes the first results of the cable program including reports on cable fabrication and reaction, first winding tests and first results of the measurement of the critical current degradation due to cabling and bending. C1 Fermilab, Batavia, IL 60510 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Bauer, P (reprint author), Fermilab, Batavia, IL 60510 USA. NR 9 TC 11 Z9 11 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2457 EP 2460 DI 10.1109/77.920360 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600253 ER PT J AU Stovall, JP Demko, JA Fisher, PW Gouge, MJ Lue, JW Sinha, UK Armstrong, JW Hughey, RL Lindsay, D Tolbert, JC AF Stovall, JP Demko, JA Fisher, PW Gouge, MJ Lue, JW Sinha, UK Armstrong, JW Hughey, RL Lindsay, D Tolbert, JC TI Installation and operation of the Southwire 30-meter high-temperature superconducting power cable SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE high temperature superconducting cable; power transmission lines; cryogenic cooling ID TRANSMISSION CABLES; AC LOSSES; DESIGN AB Southwire Company has installed, tested and is operating the first real-world application of a high-temperature superconducting cable system at its headquarters in Carrollton, Ga. The cable is powering three Southwire manufacturing plants, marking the first time a company has successfully made the difficult transition from laboratory to practical field application of an WITS cable. The cables are rated at 12.4-kV, 1250-A, 60 Hz and are cooled with pressurized liquid nitrogen at temperatures from 70-80 K. Before placing the cables into service, extensive off-line electrical testing was performed including voltage withstand, measurement of de critical current, extended load current testing, rated voltage testing and partial discharge measurement. The cables were energized on Jan. 5, 2000 for on-line testing and operation, and by the end of Aug. 2000, had provided 100% of the customer load for 2164 hours. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Southwire Co, Carrollton, GA 30119 USA. RP Stovall, JP (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 11 TC 45 Z9 49 U1 2 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2467 EP 2472 DI 10.1109/77.920363 PN 2 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600255 ER PT J AU Cha, YS Askew, TR AF Cha, YS Askew, TR TI Transient characteristics of a high-T-c superconductor tube subjected to internal and external magnetic fields SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE fault-current limiter; magnetic diffusion; magnetic shielding; pulsed current ID FAULT CURRENT LIMITER; PERFORMANCE; CYLINDER AB Transient response of a melt-cast-processed BSCCO-2212 tube at 77 K was studied using a pulsed current supply. Tests were conducted with a copper drive coil either inside or outside the superconductor tube. Experimental results show that the superconductor tube can shield the magnetic field generated by the current in the coil up to a certain limit when the coil is either inside or outside the superconductor tube. Both configurations should work for fault-current limiters. Delayed field penetration (the delay between the penetrated field and the excitation current) was observed in both cases. This delay can be explained by the concept of nonlinear magnetic diffusion, which is valid when the characteristic length of the system is much shorter than the wavelength of the driving field. The rate of magnetic diffusion is increased when (a) the local current density exceeds the critical current density and (b) the local temperature rises as a result of dissipation in the superconductor. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Kalamazoo Coll, Kalamazoo, MI 49006 USA. RP Cha, YS (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 14 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2485 EP 2488 DI 10.1109/77.920369 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600259 ER PT J AU Zbasnik, J Wang, ST Chen, JY DeVries, GJ DeMarco, R Fahmie, M Geyer, A Green, MA Harkins, J Henderson, T Hinkson, J Hoyer, EH Krupnick, J Marks, S Ottens, F Paterson, JA Pipersky, P Portmann, G Robin, DA Schlueter, RD Steier, C Taylor, CE Wahrer, R AF Zbasnik, J Wang, ST Chen, JY DeVries, GJ DeMarco, R Fahmie, M Geyer, A Green, MA Harkins, J Henderson, T Hinkson, J Hoyer, EH Krupnick, J Marks, S Ottens, F Paterson, JA Pipersky, P Portmann, G Robin, DA Schlueter, RD Steier, C Taylor, CE Wahrer, R TI ALS superbend magnet system SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE superconducting magnet; conduction cooled; cryocooler AB The Lawrence Berkeley National Laboratory is preparing to upgrade the Advanced Light Source (ALS) with three superconducting dipoles (Superbends). In this paper we present the final magnet system design which incorporates R&D test results and addresses the ALS operational concerns of alignment, availability, and economy. The design incorporates conduction-cooled Nb-Ti windings and HTS current leads, epoxy-glass suspension straps, and a Gifford-McMahon cryocooler to supply steady state refrigeration. We also present the current status of fabrication and testing. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Wang NMR, Livermore, CA 94550 USA. RP Zbasnik, J (reprint author), Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 8 TC 8 Z9 8 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2531 EP 2534 DI 10.1109/77.920381 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600270 ER PT J AU Sumption, MD Scanlan, RM Collings, EW AF Sumption, MD Scanlan, RM Collings, EW TI Coupling loss and contact resistance in cored stabrite cables - Influences of compaction and variation of core width SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE AC loss; compaction; core thickness; core width; cored Rutherford cable; interstrand coupling loss ID SUPERCONDUCTING CABLES; RUTHERFORD CABLES; STABILITY; STRANDS; MAGNETS; FIELDS AB AC loss due to coupling currents in a Rutherford cable can be modified by changing the interstrand contact resistance (ICS) by: adjusting the level of native oxidation of the strand, coating it, or by inserting a ribbon-like core into the cable itself. With regard to cored cables further effective-ICR adjustments can be achieved by changing: (i) the degree of compaction during manufacture, (ii) the thickness of the core at fixed overall thickness, and (iii) the width of the core. We report on Be results of magnetic and calorimetric AC loss measurements on stainless-steel-core stabrite cables which had been: (i) externally compacted by rolling to thicknesses of 0, 6, 9, and 11% below the standard thickness, (ii) internally compacted by being furnished with cores of thickness 1 mil (30 mum) and 2 mil(50 mum), and (iii) furnished with cores whose widths, w(core) were about 20%, 50%, 75% and 100% of the maximum possible width. The measurements H:ere made in applied AC: fields that were directed perpendicular (face-on, FO) and parallel (edge-on, EO), respectively to the broad cables faces. It was noted that: (i) the introduction of the core dramatically reduced the FO loss, (ii) core induced compaction decreased the side-by-side ICR and hence increased the EO loss, (iii) increases in either external or internal compaction still further increased the losses, particularly those in the FO direction (which of course had already been strongly core-suppressed). The loss results were also interpreted in terms of the FO-measured effective ICRs, R-perpendicular to,eff, which were found to decrease from 350 mu Omega to 40 mu Omega during the compaction of a 170 degreesC-heat treated ("ctured", HT) cable and from II mu Omega to 10 mu Omega in the case of a 200 degreesC HT one. With increase in the w(core) of a 170 degreesC HT cable R-perpendicular to,eff increased from 1.8 mu Omega to 75 mu Omega, passing through 15 mu Omega at a w(core) of 66% w(core,max). The results show that there is an opportunity for achieving the LHC-target R-perpendicular to,(eff) of 15 +/- 15 mu Omega either by compacting the standard cored cable (Tf= 200 degreesC) by 6 similar to9% or by reducing the width of the core (Tf= 170 degreesC) to within 66 +/-7% of w(max). We prefer the latter route since it exposes more of the strands (some 34 +/-7% of them) to crossover-type current sharing. C1 Ohio State Univ, Columbus, OH 43210 USA. Lawrence Berkeley Lab, Berkeley, CA USA. RP Sumption, MD (reprint author), Ohio State Univ, Columbus, OH 43210 USA. RI Sumption, Mike/N-5913-2016 OI Sumption, Mike/0000-0002-4243-8380 NR 15 TC 5 Z9 5 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2571 EP 2574 DI 10.1109/77.920393 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600280 ER PT J AU Green, MA AF Green, MA TI The effect of low temperature cryocoolers on the development of low temperature superconducting magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA AB 0The commercial development of reliable 4 K cryocoolers improves the future prospects for magnets made from low temperature superconductors (LTS). The hope of the developers of high temperature superconductors (HTS) has been to replace liquid helium cooled LTS magnets with HTS magnets that operate at or near liquid nitrogen temperature. There has been limited success in this endeavor, but continued problems with HTS conductors have greatly slowed progress toward this goal. The development of cryocoolers that reliably operate below 4 It will allow magnets made from LTS conductor to remain very competitive for many years to came. A key enabling technology for the use of low temperature cryocoolers on LTS magnets has been the development of HTS leads. This report describes the characteristics of LTS magnets that can be successfully melded to low-temperature cryocoolers. This report will also show when it is not appropriate to consider the use of low-temperature cryocoolers to cool magnets made with LTS conductor. A couple of specific examples of LTS magnets where cryocoolers can be used are given. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Green, MA (reprint author), Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 6 TC 4 Z9 7 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2615 EP 2618 DI 10.1109/77.920404 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HR UT WOS:000168285600291 ER PT J AU Groves, JR Arendt, PN Kung, H Foltyn, SR DePaula, RF Emmert, LA Storer, JG AF Groves, JR Arendt, PN Kung, H Foltyn, SR DePaula, RF Emmert, LA Storer, JG TI Texture development in IBAD MgO films as a function of deposition thickness and rate SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE IBAD; MgO; bi-axial texture; superconductivity ID COATED CONDUCTORS AB We have examined the effect of film thickness on in-plane texture for ion-beam assisted deposition (IBAD) of MgO films. Plan-view dark-field transmission electron microscopy (TEM) has revealed that texture develops rapidly, reaching its best value at a critical thickness of similar to 10 nm. These results have been confirmed by quantifying the in-plane texture of these samples at each thickness with X-ray thickness X-ray diffraction W-scans. we have also examined the effects of variable deposition rate on texture formation. X-ray diffraction shows that the optimum in-plane texture is achieved at the critical thickness with a rate of 0.2 nm/s. However, TEM imaging has shown that the distribution of well-aligned grains decreases with an increase in rate. As such, deposition at 0.1 nm/s was found to be sufficient for achieving good in-plane distribution values and good surface coverage for subsequent depositions. By combining the results of both of these experiments, we were then able to optimize our deposition process and apply them to the growth of IBAD MgO on metal substrates. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci, Los Alamos, NM 87545 USA. 3M Corp, Corp Proc Technol Ctr, Mendota Hts, MN USA. RP Groves, JR (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci, Los Alamos, NM 87545 USA. NR 11 TC 54 Z9 56 U1 1 U2 13 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2822 EP 2825 DI 10.1109/77.919650 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900035 ER PT J AU Dawley, JT Clem, PG Siegal, MP Overmyer, DL Rodriguez, MA AF Dawley, JT Clem, PG Siegal, MP Overmyer, DL Rodriguez, MA TI Thick sol-gel derived YBa2Cu3O7-delta films SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE materials processing; sol-gel; superconducting films ID 001 LAALO3; GROWTH; BA2YCU3O7-X; DEPOSITION; MICROSTRUCTURE AB YBa2Cu3O7-delta films have been prepared by spin-coating solutions of metal acetates dissolved in trifluoroacetic acid/methanol and trifluoroacetic acid/isopropanoyl/1,3 propanediol onto LaAlO3 (100) substrates. By using a rapid, low pO(2) pyrolysis process, high-quality diol films (0.25 mum thick) with J(c) values as high as 14 MA/cm(2) and 2 MA/cm(2) at 7 K and 77 K, respectively, were fabricated in one tenth the time, compared to conventional processing schemes. The effect of multicoating, in order to reach YBCO film thicknesses of 1.5 mum, on the J(c) was also studied. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dawley, JT (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 18 TC 39 Z9 42 U1 1 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2873 EP 2876 DI 10.1109/77.919662 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900047 ER PT J AU Rupich, MW Li, Q Annavarapu, S Thieme, C Zhang, W Prunier, V Paranthaman, M Goyal, A Lee, DF Specht, ED List, FA AF Rupich, MW Li, Q Annavarapu, S Thieme, C Zhang, W Prunier, V Paranthaman, M Goyal, A Lee, DF Specht, ED List, FA TI Low cost Y-Ba-Cu-O coated conductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE high temperature superconductors; epitaxial layers; YBaCuO ID FILMS; GROWTH; DEPOSITION; TAPES; OXIDE AB Solution-based techniques have been examined as potential low-cost processes for manufacturing YBCO coated conductors. YBCO films prepared from metal trifluoroacetate precursors have achieved performance levels equaling or exceeding that of vapor deposited films with the same thickness on CeO2/YSZ(sc) substrates. J(c)'s of 4.5 MA/cm(2) and 2 MA/cm(2) have been achieved in 0.4 mum thick YBCO films on CeO2/YSZ(sc) and CeO2/YSZ/CeO2/Ni substrates, respectively. Textured Gd2O3 buffer layers have been deposited on deformation textured Ni substrates in a reel-to-reel process. The performance of YBCO films deposited on substrates containing the Gd2O3 seed layers is comparable in performance to YBCO films grown on all vacuum deposited buffer layers. C1 Amer Semicond, Westborough, MA 01518 USA. Elect France, ERMEL CIMA, Res & Dev, Les Renardieres, France. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Rupich, MW (reprint author), Amer Semicond, Westborough, MA 01518 USA. RI Specht, Eliot/A-5654-2009; Paranthaman, Mariappan/N-3866-2015 OI Specht, Eliot/0000-0002-3191-2163; Paranthaman, Mariappan/0000-0003-3009-8531 NR 15 TC 64 Z9 65 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2927 EP 2930 DI 10.1109/77.919675 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900060 ER PT J AU Sathyamurthy, S Salama, K AF Sathyamurthy, S Salama, K TI Application of solution deposition to fabricate Y-Ba-Cu-O coated conductor. SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE coated conductors; metallorganic decomposition; strontium titanate films; YBCO films ID THIN-FILMS; BA2YCU3O7-X; YBA2CU3O7; GROWTH; TAPES AB This paper demonstrates the successful application of solution deposition techniques to deposit buffer layers and YBCO films on flexible metal substrates, thus making coated conductor fabrication scalable and cost effective. We present results obtained using strontium titanate buffer layers. These buffer layers, processed on single crystal substrates using solution precursors and heat treated in a reducing atmosphere are highly textured and have a uniform smooth surface. YBCO films, 0.3-0.5mm thick, deposited on these buffered single crystals using the trifluoroacetate process shows good superconducting properties, YBCO films processed on strontium titanate buffered lanthanum aluminate substrates have an onset of transition around 90-91K and critical current densities of the order of 10(5)-10(6) A/cm(2) at 77K and self field, These processing techniques have been extended to textured nickel substrates, These results offer promise to the development of scalable, solution based processing route to deposit buffer layers and YBCO films on flexible metallic textured tapes. C1 Univ Houston, Houston, TX 77204 USA. RP Sathyamurthy, S (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 11 TC 17 Z9 19 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2935 EP 2938 DI 10.1109/77.919677 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900062 ER PT J AU Solovyov, VF Wiesmann, HJ Wu, LJ Zhu, Y Suenaga, M AF Solovyov, VF Wiesmann, HJ Wu, LJ Zhu, Y Suenaga, M TI Ex-situ post-deposition processing for large area Y1Ba2Cu3O7 films and coated tapes SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE barium fluoride process; coated conductors; YBCO ID THICK YBA2CU3O7 FILMS AB Ex-situ post-deposition reaction processing is considered a promising alternative to in-situ physical vapor deposition techniques for coated Y1Ba2Cu3O7 conductor development. It was reported recently, that attempts at ex-situ processing of long Y1Ba2Cu3O7 precursor tapes resulted in an inhomogeneous growth rate over the tape length and rather poor properties for the whole sample. We performed a set of experiments in order to clarify the mechanisms for the ex-situ processing of large area films and estimate properties of long coated conductors manufactured by the ex-situ technique. It was found that rate limiting step of ex-situ growth of Y1Ba2Cu3O7 is removal of the reaction product, hydrofluoric acid, by both gas diffusion and convection in the reaction atmosphere, We report on a quantitative model that well describes the observed growth rates for films with various areas. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Solovyov, VF (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RI Solovyov, Vyacheslav/A-7724-2009; OI Solovyov, Vyacheslav/0000-0003-1879-9802 NR 9 TC 33 Z9 35 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2939 EP 2942 DI 10.1109/77.919678 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900063 ER PT J AU Holesinger, TG Ayala, A Baurceanu, RM Maroni, VA AF Holesinger, TG Ayala, A Baurceanu, RM Maroni, VA TI Investigation of the initial stages of processing Bi-2223 multifilamentary tapes by analytical electron microscopy SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE high temperature superconductor; lead; liquid phase; TEM; sintering ID CU-O SYSTEM; THIN-FILMS; PHASE; BI; MECHANISM AB Analytical transmission electron microscopy (TEM) was used to probe the formation of liquid phases in multifilamentary Bi-2223 tapes. Silver was found to nucleate small amounts of liquid phase early in the processing. However, liquid formation was primarily associated with the 14-24 AEC and time at temperature (induction period) was the major factor determining the amounts of lead-rich liquid phase formation in these tapes. The compositions of the lead-rich liquid phases were measured quantitatively. The data presented is consistent with a mechanism whereby Bi-2223 can precipitate from a liquid phase. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Holesinger, TG (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 17 TC 9 Z9 9 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 2991 EP 2994 DI 10.1109/77.919691 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900076 ER PT J AU Rikel, MO Williams, RK Cai, XY Polyanskii, AA Jiang, J Wesolowski, D Hellstrom, EE Larbalestier, DC DeMoranville, K Riley, GN AF Rikel, MO Williams, RK Cai, XY Polyanskii, AA Jiang, J Wesolowski, D Hellstrom, EE Larbalestier, DC DeMoranville, K Riley, GN TI Overpressure processing Bi2223/Ag tapes SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Bi2223/Ag tapes; critical currents; Magneto-Optical studies; overpressure processing ID STABILITY; DENSITY AB We report on the effect of overpressure processing on the electromagnetic properties and microstructure of monocore and multifilamentary Bi2223/Ag tapes. Samples at various stages of the usual thermo-mechanical processing for Bi2223/Ag tapes (from as-rolled to fully processed) were subjected to annealing at 815-820 degreesC for 18-108 h in a static Ar + O-2 atmosphere at the overall pressure 17.5 +/- 0.5 MPa (pO(2) = 0.003-0.02 MPa), Density measurements, microhardness tests, and SEM examination of polished sections reveal a notable densification of overpressure-processed samples. For partly reacted (so called HT1) samples, we found that overpressure processing for 36 h is sufficient to densify the Bi2223 core from 70 +/- 5 to 87 +/- 4% theoretical density and increase self-field J(c)(77K) from 8 +/- 1 to 30 +/- 5 kA/cm(2) The results show that onestep processing of Bi2223/Ag tapes is possible. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Wisconsin, Ctr Appl Superconduct, Madison, WI 53705 USA. Amer Superconductor Corp, Westborough, MA 01581 USA. RP Hellstrom, EE (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Larbalestier, David/B-2277-2008; Jiang, Jianyi/F-2549-2017; OI Larbalestier, David/0000-0001-7098-7208; Jiang, Jianyi/0000-0002-1094-2013; Rikel, Mark/0000-0002-4537-0772 NR 14 TC 11 Z9 12 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3026 EP 3029 DI 10.1109/77.919700 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900085 ER PT J AU Hasegawa, T Ohtani, N Koizumi, T Aoki, Y Nagaya, S Hirano, N Motowidlo, L Sokolowski, RS Scanlan, RM Dietderich, DR Hanai, S AF Hasegawa, T Ohtani, N Koizumi, T Aoki, Y Nagaya, S Hirano, N Motowidlo, L Sokolowski, RS Scanlan, RM Dietderich, DR Hanai, S TI Improvement of superconducting properties of Bi-2212 round wire and primary test results of large capacity Rutherford cable SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Bi-2212; round wire; Rutherford type; large capacity cable AB We have developed HTS cables using Bi-2212 round wires, which have high mechanical strength and an average J(c) of 200kA/cm(2) at 4.2K in self-field. Four designs of cables were fabricated in this work and those cables could carry I-c values from 1kA to 10kA at 4.2K and self-field depending on the number of strands. A 70m-long 20-strand Rutherford cable was successfully manufactured. Optimization of heat treatment conditions was effective to reduce I-c degradation observed in the case of heat treatment with a long length. I-c vales of a Rutherford table were measured under loading at 4.2K in 4T, The critical values of the stress on face loading and edge loading were 60MPa and 100MPa, respectively. We successfully obtained high J(c) value of 500kA/cm(2), which was almost double that of the conventional wires capitalize "Rutherford". C1 Showa Elect Wire & Cable Co, Sagamihara, Kanagawa 2291133, Japan. Chubu Elect Power Co Inc, Midori Ku, Nagoya, Aichi 4598522, Japan. IGC Adv Superconductors, Waterbury, CT 06740 USA. Intermagnet Gen Co, Latham, NY 12110 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. Toshiba Co Ltd, Tsurumi Ku, Yokohama, Kanagawa 2300045, Japan. RP Hasegawa, T (reprint author), Showa Elect Wire & Cable Co, 4-1-1 Minami Hashimoto, Sagamihara, Kanagawa 2291133, Japan. NR 4 TC 47 Z9 47 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3034 EP 3037 DI 10.1109/77.919702 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900087 ER PT J AU Trociewitz, UP Sahm, PR Koritala, RE Brandao, L Bacaltchuk, C Schwartz, J AF Trociewitz, UP Sahm, PR Koritala, RE Brandao, L Bacaltchuk, C Schwartz, J TI Microstructural development and superconducting properties of BaO2-added Bi2Sr2CaCu2O8+x SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Bi-2212; powder in tube (PIT) process; BaO2 addition; texture; transport critical current; artificial pinning center (APC) ID ADDITIONS AB Investigations on the effects of Ba additions in Bi-2212 superconductors are focussed on compositional, microstructural, and magnetization studies. In previous studies, we showed that BaO2 reacts with Bi-2212 to form second phases. Zero-field and in-field transport properties in Ag-clad BaO2 added Bi-2212 tapes had been improved at 4.2 K [1]-[3]. SEM micrographs, pole figures, and transport critical currents versus magnetic field orientation suggest that BaO2 has a strong influence on the microstructural properties. Magnetization studies revealed that BaO2 does not affect the pinning properties of optimally added Bi-2212. To estimate the potential of BaO2 additions in creating possible pinning sites. TEM investigations were carried out focussing on sub-micrometer inclusions and growth defects in the superconducting phase. C1 Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. FSU, Coll Engn, FAMU, Dept Engn Mech, Tallahassee, FL 32310 USA. Univ Technol, Rhein Westfal TH Aachen, D-52056 Aachen, Germany. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Inst Mil Eng, Dept Eng Mecan & Mat, BR-22270290 Rio De Janeiro, Brazil. RP Trociewitz, UP (reprint author), Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. RI Schwartz, Justin/D-4124-2009; Koritala, Rachel/F-1774-2011; Brandao, Luiz Paulo/B-2714-2013 OI Schwartz, Justin/0000-0002-7590-240X; Brandao, Luiz Paulo/0000-0002-2623-648X NR 9 TC 0 Z9 0 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3054 EP 3057 DI 10.1109/77.919707 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900092 ER PT J AU Bhattacharya, RN Feldmann, M Larbalestier, D Blaugher, RD AF Bhattacharya, RN Feldmann, M Larbalestier, D Blaugher, RD TI Electrodeposition process for the preparation of superconducting thallium oxide films SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE electrodeposition; superconductors; magnetooptical image; thallium-oxide ID AG AB A two-layer electrodeposition process was developed to deposit biaxially textured thallium-oxide superconductor films on Ag-coated, single-crystal substrates, Transport measurements for the electrodeposited, thallium-oxide-based superconductor films show values above 10(6) A/cm(2) at 77K in zero field. In this paper we are reporting magneto-optical imaging data on electrodeposited 1223 thallium-oxide superconductor films. Magneto-optical imaging provides insight into the nature of current flow in the Tl-oxide superconductor, and thus will help us to improve the critical current density in bulk high-temperature superconductor wire or tape. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Wisconsin, Ctr Appl Superconduct, Madison, WI 53706 USA. RP Bhattacharya, RN (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Larbalestier, David/B-2277-2008 OI Larbalestier, David/0000-0001-7098-7208 NR 10 TC 6 Z9 6 U1 2 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3102 EP 3105 DI 10.1109/77.919719 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900104 ER PT J AU Paranthaman, M Chirayil, TG Sathyamurthy, S Beach, DB Goyal, A List, FA Lee, DF Cui, X Lu, SW Kang, B Specht, ED Martin, PM Kroeger, DM Feenstra, R Cantoni, C Christen, DK AF Paranthaman, M Chirayil, TG Sathyamurthy, S Beach, DB Goyal, A List, FA Lee, DF Cui, X Lu, SW Kang, B Specht, ED Martin, PM Kroeger, DM Feenstra, R Cantoni, C Christen, DK TI Fabrication of long lengths of YBCO coated conductors using a continuous reel-to-reel dip-coating unit SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE solution precursors; RE2O3 buffer layers; YBCO coated conductors; textured metal substrates ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; EPITAXIAL-GROWTH; THIN-FILMS AB A low-cost, non-vacuum, solution precursor route has been developed to produce epitaxial Gd2O3 and Eu2O3 buffer layers and YBa2Cu3O7-delta (YBCO) superconductors on biaxially textured metal substrates. On sol-gel Eu2O3 seed layers with sputtered YSZ nod CeO2 top layers, YBCO film with a J(c) Of over 1 MA/cm(2) at 77 K was obtained, On all solution buffer layers (CeO2/Eu2O3/Ni), YBCO film with a J(c) of 200,000 A/cm(2) at 77 K was grown using pulsed laser deposition (PLD), Meter lengths of epitaxial and crack-free Gd2O3 buffer layers were fabricated on cube textured Ni-W (3 at. %) substrates for the first time. High quality YBCO films were deposited on Rolling-Assisted Biaxially Textured Substrates (RABiTS) using a trifluoroacetate (TFA) precursor approach. The precursors were either spin-coated or dip-coated and decomposed in a newly developed fast 3-hour burn-out step followed by post-annealing. In a stationary burn-out route, we have produced 40 cm long crack-free YBCO TFA precursors on RABiTS, On short segments, YBCO films with a J(c),of over 500,000 A/cm(2) at 77 K were grown on all PLD buffered-Ni substrates (CeO2/YSZ/CeO2/Ni). C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Paranthaman, M (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Christen, David/A-9709-2008; Specht, Eliot/A-5654-2009; Paranthaman, Mariappan/N-3866-2015; Cantoni, Claudia/G-3031-2013 OI Specht, Eliot/0000-0002-3191-2163; Paranthaman, Mariappan/0000-0003-3009-8531; Cantoni, Claudia/0000-0002-9731-2021 NR 14 TC 45 Z9 48 U1 0 U2 10 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3146 EP 3149 DI 10.1109/77.919730 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900115 ER PT J AU Diehl, RC Fleshler, S Mason, R Christopherson, C DeMoranville, K Harnois, R Otto, A Riley, GN Serres, E Willis, JO Boenig, HJ Schillig, JB AF Diehl, RC Fleshler, S Mason, R Christopherson, C DeMoranville, K Harnois, R Otto, A Riley, GN Serres, E Willis, JO Boenig, HJ Schillig, JB TI Properties of a prototype Bi-based HTS composite with a high resistivity sheath for resistive fault current limiting applications SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE current limiters; superconductors (high temperature); fault currents ID CURRENT LIMITERS AB Prototype Bi-2223 based composite conductors have been fabricated to provide inherent passive fault current limiting functionality in devices. An HTS insert strand possessing a high resistivity sheath (HRS) was laminated to two metallic strips to provide additional capacity to absorb the heat generated during a fault. Sheath resistivities up to 45 times that of pure Ag were achieved, We summarize the electrical response of 10 to 100 cm straight sections of conductor to pulsed de and ae currents several times the critical current. DC pulsed I-V characteristics have been obtained over 7 to 8 orders of magnitude of voltage, For electric field levels around 10 V/m, the I-V curves demonstrate the advantage of the HRS conductor in facilitating fault current limiting over the conventional Ag-sheathed Bi-2223 approach. The recovery time for ac faults of 10 V/m was mapped out for various fault hold times. Instantaneous operational recovery was observed for fault hold times up to 3 seconds. C1 Amer Superconductor Corp, Westborough, MA 01581 USA. Elect France, R&D Div, F-92141 Clamart, France. Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Diehl, RC (reprint author), Amer Superconductor Corp, Westborough, MA 01581 USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3265 EP 3268 DI 10.1109/77.919759 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900143 ER PT J AU Prorok, BC Park, JH Goretta, KC Koritala, RE Balachandran, U McNallan, MJ AF Prorok, BC Park, JH Goretta, KC Koritala, RE Balachandran, U McNallan, MJ TI Internally oxidized Ag/1.2 at.% Mg sheaths for Bi-2223 tapes SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Ag alloy; wire; tape; mechanical properties ID IN-TUBE TAPES; MECHANICAL-PROPERTIES; COMPOSITE CONDUCTORS; PHASE-FORMATION; SOLID SILVER; AG; MICROSTRUCTURE; DEFORMATION; DIFFUSIVITY; SOLUBILITY AB Bi-2223 tapes sheathed in dispersion-hardened Ag alloys that contain Mg have not generally achieved superconducting properties comparable to those of tapes sheathed in pure Ag. Factors involved in the internal oxidation process, such as oxygen diffusion and evolution of the grain structure of the sheath, appear to affect phase development of the Bi-2223 superconductor, Ag and Ag/1.2 at.% Mg sheaths, and alloy/Bi-2223 composite tapes, have been prepared and heat treated. Thermal processing procedures were optimized with respect to the diffusion of oxygen and strength profiles of the sheaths. C1 Northwestern Univ, Dept Mech Engn, Evanston, IL 60208 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Univ Illinois, Chicago, IL 60607 USA. RP Prorok, BC (reprint author), Northwestern Univ, Dept Mech Engn, Evanston, IL 60208 USA. RI Prorok, Barton/A-7404-2010; Koritala, Rachel/F-1774-2011 NR 25 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3273 EP 3276 DI 10.1109/77.919761 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900145 ER PT J AU Cantoni, C Aytug, T Verebelyi, DT Paranthaman, M Specht, ED Norton, DP Christen, DK AF Cantoni, C Aytug, T Verebelyi, DT Paranthaman, M Specht, ED Norton, DP Christen, DK TI Conductive buffer layers and overlayers for the thermal stability of coated conductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE buffer layers; contact resistance; critical currents; metallic oxides; superconducting tapes AB We analyze fundamental issues related to the thermal and electrical stability of a coated conductor during its operation. We address the role of conductive buffer layers in the stability of Ni-based coated conductors, and the effect of a metallic cap layer on the electrical properties of Ni alloy-based superconducting tapes. For the first case we report on the fabrication of a fully conductive RABiTS architecture formed of bilayers of conductive oxides SrRuO3 and LaNiO3 on textured Ni tapes. For the second case we discuss measurements of current-voltage relations on Ag/YBa2Cu3O7-delta and Cu/Ag/ YBa2Cu3O7-delta prototype multilayers on insulating substrates. Limitations on the overall tape structure and properties that are posed by the stability requirement are presented. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Cantoni, C (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Specht, Eliot/A-5654-2009; Paranthaman, Mariappan/N-3866-2015; Cantoni, Claudia/G-3031-2013 OI Specht, Eliot/0000-0002-3191-2163; Paranthaman, Mariappan/0000-0003-3009-8531; Cantoni, Claudia/0000-0002-9731-2021 NR 7 TC 19 Z9 25 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3309 EP 3312 DI 10.1109/77.919770 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900154 ER PT J AU Thieme, CLH Annavarapu, S Zhang, W Prunier, V Fritzemeier, L Li, Q Schoop, U Rupich, MW Gopal, M Foltyn, SR Holesinger, T AF Thieme, CLH Annavarapu, S Zhang, W Prunier, V Fritzemeier, L Li, Q Schoop, U Rupich, MW Gopal, M Foltyn, SR Holesinger, T TI Non-magnetic substrates for low cost YBCO coated conductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VA DE YBaCuO coated conductor; superconductor AB CuNiAl and NiCr alloys were made and processed to non-magnetic, bi-axially textured substrates. Epitaxial YSZ and YBCO were deposited by pulsed laser deposition on the CuNiAl, Samples were cross sectioned and investigated with TEM. It appears that Al forms a thin oxide layer at the CuNiAl surface that acts as a template for the subsequent YSZ layer. The 1.2 mum YBCO layer had a current density of 0.16MA/cm(2) at 75K and self field. On the NiCr substrates an Y2O5 Seed layer was deposited with E-beam evaporation, followed by RF sputter deposition of YSZ and a CeO2 cap layer. These substrates were coated with a 0.4 mum YBCO layer using a trifluoroacetate solution, a very cost effective metal-organic deposition process, These samples carried critical currents exceeding 0.7MA/cm(2) at 77K, self field. C1 AMSC, Westborough, MA 01581 USA. MIT, Ctr Mat Proc, Cambridge, MA 02139 USA. Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP AMSC, 2 Technol Dr, Westborough, MA 01581 USA. EM cthieme@amsuper.com; mgopal@mit.edu; sfoltyn@lanl.gov; holesinger@lanl.gov NR 10 TC 15 Z9 16 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3329 EP 3332 DI 10.1109/77.919775 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900159 ER PT J AU Lelovic, M Koritala, R Fisher, B Balachandran, U Vo, N Selvamanickam, V Haldar, P AF Lelovic, M Koritala, R Fisher, B Balachandran, U Vo, N Selvamanickam, V Haldar, P TI Novel technique for improving field dependence in Bi-2223 superconducting tapes at 77 K SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Bi2Sr2Ca2Cu3Oy (Bi-2223) superconducting; tapes; defects; MgO; pinning; powder-in-tube (PIT) technique ID FABRICATION AB In order to use Bi2Sr2Ca2Cu3Oy (Bi-2223) superconducting tapes for practical applications at liquid nitrogen temperatures, the critical current density (J(c)) must be as high as possible under an applied magnetic field. In this work, an attempt was made to increase pinning in Bi-2223 superconducting tapes by creating defects at the interface between a Bi-2223 superconductor and an MgO single crystal. Reference samples showed decreased I-c values at 77K in a 0.4 T field applied perpendicular to the width of the tape to approximate to4 to 7% of the I-c value in zero field. With improved pinning, the I, value in the field decreased to 12 to 20% of the I-c value in zero field. Results were compared with in-field performance of high-quality coated YBa2Cu3OY (Y-123) tapes, which showed an infield decrease to approximate to 30% of the I-c value in zero field. C1 Argonne Natl Lab, Argonne, IL 60439 USA. IGC SuperPower, Schenectady, NY 12304 USA. RP Lelovic, M (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Koritala, Rachel/F-1774-2011 NR 6 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3349 EP 3352 DI 10.1109/77.919780 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900164 ER PT J AU Holesinger, TG Foltyn, SR Arendt, PN Jia, QX Dowden, PC DePaula, RF Groves, JR AF Holesinger, TG Foltyn, SR Arendt, PN Jia, QX Dowden, PC DePaula, RF Groves, JR TI A comparison of buffer layer architectures on continuously processed YBCO coated conductors based on the IBAD YSZ process SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE coated conductor; IBAD; TEM; YBCO ID YBA2CU3O7-DELTA THICK-FILMS; PULSED-LASER DEPOSITION; ALLOYS AB The microstructures of continuously processed YBa2Cu3Oy (YBCO) coated conductors processed with three different architectures are presented. YBCO films were deposited directly on ion-beam-assisted deposition (IBAD) yttria-stabilized zirconia (YSZ) or on intervening layers of Y2O3 Or CeO2. Different interfacial reactions were observed in each case. The volume changes that occur with the interfacial reactions were calculated based on the identified reaction products. The calculated volume changes correlate with the observed micostructures and appear to be an important factor in determining an optimal buffer layer system. The interfacial reactions do not preclude the attainment of high I-c and J(c) values in these coated conductors. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Holesinger, TG (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Jia, Q. X./C-5194-2008 NR 14 TC 35 Z9 35 U1 0 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3359 EP 3364 DI 10.1109/77.919783 PN 3 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900167 ER PT J AU Peng, LSJ Wang, WZ Jo, W Ohnishi, T Marshall, AF Hammond, RH Beasley, MR Peterson, EJ Ericson, RE AF Peng, LSJ Wang, WZ Jo, W Ohnishi, T Marshall, AF Hammond, RH Beasley, MR Peterson, EJ Ericson, RE TI In situ high rate growth of high temperature superconductor tapes SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE critical current; e-beam deposition; IBAD; in situ growth; phase stability; YBCO superconductor tapes ID THIN-FILMS; INSITU GROWTH; YBA2CU3O7-DELTA; SYSTEM AB In situ high rate growth of YBa2Cu3O7-delta superconducting films has been carried out using e-beam deposition. A deposition flux controller was developed to monitor and control the deposition rates using tunable diode, laser-based, atomic absorption. A wide range of temperatures, deposition rates, and oxygen fluxes including atomic, molecular oxygen, have been explored in order to understand both kinetic and thermodynamic stability. Critical current density above 1 MA/cm(2) has been achieved on SrTiO3 substrate samples with growth rates up to 75 Angstrom /sec. Samples prepared on IBAD YSZ/Ni tapes exhibit similar resistivity properties and x-ray diffraction patterns. However, critical current densities of the tapes are around 5 kA/cm(2) or lower. The poor critical current density of the tape is attributed to interactions between the YBa2Cu3O7-delta film and the YSZ buffer layer. C1 Stanford Univ, Stanford, CA 94305 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. 3M Corp, St Paul, MN 55144 USA. RP Peng, LSJ (reprint author), Conductus Inc, 969 W Maude Ave, Sunnyvale, CA 94086 USA. NR 17 TC 12 Z9 12 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3375 EP 3378 DI 10.1109/77.919786 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900170 ER PT J AU Ekin, JW Bray, SL Cheggour, N Clickner, CC Foltyn, SR Arendt, PN Polyanskii, AA Larbalestier, DC McCowan, CN AF Ekin, JW Bray, SL Cheggour, N Clickner, CC Foltyn, SR Arendt, PN Polyanskii, AA Larbalestier, DC McCowan, CN TI Transverse stress and fatigue effects in Y-Ba-Cu-O coated IBAD tapes SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VA DE coated conductors; critical current; electromechanical; IBAD; mechanical; stress; transverse stress ID YBA2CU3O7-DELTA THICK-FILMS; BUFFER LAYERS; CONDUCTORS; FIELD AB Measurements of the effects of static and cyclic (fatigue) transverse stress on the critical current of Ya-Ba-Cu-O coated tapes made by ion-beam-assisted deposition (IBAD) are reported at 76 K in self magnetic field. Ya-Ba-Cu-O films (similar to1 mum thick) on Inconel substrates (100 mum thick) with IBAD buffer layers had critical-current densities J(c) exceeding 1 MA/cm(2) and n values of about 50 (where n is an index of the sharpness of the superconductor-to-normal transition). Under static loads of 100 MPa, the degradation in J(c) was less than 5% (7% at 120 MPa). When subjected to cyclic loading, there was less than 2% additional degradation in J(c) after 2000 fatigue cycles. Microscopic examination of the samples indicates that this limited J(c) degradation may have arisen from longitudinal cracks forming near the edges of the sample after being subjected to these high transverse pressures. This fracture mode would indicate that longitudinal side support from high-yield substrates or epoxy impregnation of magnet structures may provide additional tolerance against degradation in J(c) from transverse stress. C1 Natl Inst Stand & Technol, Boulder, CO 80305 USA. Los Alamos Natl Lab, Los Alamos, NM USA. Univ Wisconsin, Madison, WI USA. RP Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80305 USA. EM ekin@boulder.nist.gov; cheggour@boulder.nist.gov RI Cheggour, Najib/K-2769-2012; Larbalestier, David/B-2277-2008 OI Cheggour, Najib/0000-0002-0741-3065; Larbalestier, David/0000-0001-7098-7208 NR 16 TC 20 Z9 20 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3389 EP 3392 DI 10.1109/77.919790 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900174 ER PT J AU Chudzik, MP Koritala, RE Luo, ZP Miller, DJ Balachandran, U Kannewurf, CR AF Chudzik, MP Koritala, RE Luo, ZP Miller, DJ Balachandran, U Kannewurf, CR TI Mechanism and processing dependence of biaxial texture development in magnesium oxide thin films grown by inclined-substrate deposition SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VA ID BEAM-ASSISTED DEPOSITION; MGO AB Biaxially textured thin films of MgO were deposited on metal foils as epitaxial template layers for high-T(c) superconducting tapes. The MgO was deposited by electron beam evaporation on substrates inclined to the atomic vapor. The processing dependence of biaxial texture on inclination angle, deposition rate, film thickness, and substrate was investigated by four-circle X-ray diffraction and selected-area electron diffraction, Texturing of the MgO was a selective growth process whereby the texture improves with increasing film thickness, This growth process differs from the texturing of h MgO in ion-beam-assisted deposition, which is nucleation controlled and requires an amorphous substrate. It was experimentally found that the in-plane texture of the MgO thick films was not dependent on deposition rate from 2.5 to 100 Angstrom /s, making this technique amenable to cost-effective production. This result has important implications to manufacturing scaleup of YBa(2)Cu(3)O(x) coated tapes. The mechanism for the creation of biaxial texture in the MgO films was determined to be from the combined effects of the cubic equilibrium crystal habit of MgO and columnar self-shadowing. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Northwestern Univ, Dept Elect & Comp Engn, Evanston, IL 60208 USA. RP Chudzik, MP (reprint author), IBM Microelect, Semicond Res & Dev Ctr, 2070 RTE 52, Hopewell Jct, NY 12533 USA. RI Koritala, Rachel/F-1774-2011; Luo, Zhiping/C-4435-2014 OI Luo, Zhiping/0000-0002-8264-6424 NR 12 TC 30 Z9 30 U1 1 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3469 EP 3472 DI 10.1109/77.919810 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900194 ER PT J AU Koritala, RE Chudzik, MP Luo, ZP Miller, DJ Kannewurf, CR Balachandran, U AF Koritala, RE Chudzik, MP Luo, ZP Miller, DJ Kannewurf, CR Balachandran, U TI Transmission electron microscopy investigation of texture development in magnesium oxide buffer layers SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE buffer layers; electron microscopy; inclined substrate deposition; superconducting films ID MGO AB Biaxially textured magnesium oxide (MgO) buffer layers were grown by inclined substrate deposition and examined before YBa2Cu3O7-x deposition to optimize their texture, Transmission electron microscopy of buffer layers in both cross-sectional and plan view was used to investigate film microstructure and texture development as a function of deposition thickness (0.05-3 mum) and substrate inclination angle (0-55 degrees from the substrate normal). It was determined that the combined effects of preferential growth of the {200} equilibrium crystal habit of MgO and shadowing by columnar grains led to the development of off-axis (200) -textured films. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Northwestern Univ, Dept Elect & Comp Engn, Evanston, IL 60208 USA. RP Koritala, RE (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Koritala, Rachel/F-1774-2011; Luo, Zhiping/C-4435-2014 OI Luo, Zhiping/0000-0002-8264-6424 NR 7 TC 18 Z9 18 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3473 EP 3476 DI 10.1109/77.919811 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900195 ER PT J AU Truchan, TG Chudzik, MP Fisher, BL Erck, RA Goretta, KC Balachandran, U AF Truchan, TG Chudzik, MP Fisher, BL Erck, RA Goretta, KC Balachandran, U TI Effect of ion-beam parameters on in-plane texture of yttria-stabilized zirconia thin films SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE biaxial texture; IBAD; coated conductors ID ASSISTED DEPOSITION; BIAXIAL ALIGNMENT; IBAD AB Biaxially textured thin films of 8-mole%-yttria-stabilized zirconia (YSZ) were deposited by ion-beam-assisted deposition (IBAD) on polished Hastelloy-C tapes. These films serve as epitaxial template layers for highly textured Y-Ba-Cu-O superconductor thin films. YSZ films were deposited to a gross thickness of approximate to1.6 pm by electron beam evaporation. A 300-eV Ar/10% O-2 ion beam bombarded the substrate at an off-normal angle during deposition. The ion-to-atom arrival ratio (r-value) was varied by independently adjusting the deposition rate and the ion current density. X-ray pole figures and phi scans were used to investigate in-plane texture. Profilometry and spectral reflectivity H ere utilized to measure the net film thickness. A two-dimensional texture/thickness contour map was generated and used to optimize the in-plane texture of the YSZ and to minimize processing time. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Truchan, TG (reprint author), Opto Power Corp, 3321 E Global Loop, Tucson, AZ 85706 USA. NR 13 TC 4 Z9 4 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3485 EP 3488 DI 10.1109/77.919814 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900198 ER PT J AU Jia, QX Arendt, PN Foltyn, SR Holesinger, TG DePaula, RF AF Jia, QX Arendt, PN Foltyn, SR Holesinger, TG DePaula, RF TI Superconducting YBCO films on polycrystalline yttrium-iron-garnet using IBAD-YSZ as a template SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE ferrites; high-temperature superconductors; microwave devices; thin films ID MICROWAVE SURFACE-RESISTANCE; TEXTURED BUFFER LAYERS; YBA2CU3O7-X THIN-FILMS; BICRYSTALS; FERRITE AB Monolithic integration of high quality YBCO films on polycrystalline yttrium-iron-garnet (YIG) substrates represents an advance of great technical significance for magnetically tunable microwave components, We have solved the problems of crystallographic incompatibility between the two materials and the lack of an epitaxial template for the growth of well-oriented YBCO films. Using a buffer layer of biaxially oriented yttria-stabilized zirconia (YSZ), deposited by an ion-beam-assisted-deposition (IBAD) technique, we routinely produced device quality YBCO films on polycrystalline YIG substrates, The YBCO films were c-axis oriented with an inplane mosaic spread of less than 7 degrees FWHM. The films had transition temperatures above 88 K, transition widths less than 0.3 K, and critical current densities above 10(6) A/cm(2) in self-field at 75 K. The surface resistance of the films was similar to0.86 m Omega at 10 GHz and 76 K. C1 Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Jia, QX (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 12 TC 2 Z9 2 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3489 EP 3492 DI 10.1109/77.919815 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900199 ER PT J AU Barzi, E Gregory, E Pyon, T AF Barzi, E Gregory, E Pyon, T TI Heat treatment optimization of internal tin Nb3Sn strands SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE critical current density; heat treatment; internal tin; subelement AB The development of high critical current density (J(c)) multifilamentary Nb3Sn strands with low magnetization is important for many technological applications, including construction of high field accelerator magnets. To achieve this goal, strand R&D is actively pursued by Fermilab and IGC using the internal Tin process. The J(c) of a Nb3Sn strand made with the Internal Tin technology depends on numerous factors, including Nh filament size and heat treatment cycle. Various heat treatments were applied to Nb3Sn strands of different designs produced by IGC, The effect of filament size was studied both during the Nb3Sn layer growth and after complete reaction. The resulting J(c)'s are presented, as well as SEM microscopy of strand sections. C1 Fermilab, Batavia, IL 60510 USA. IGC AS, Waterbury, CT 06704 USA. RP Barzi, E (reprint author), Fermilab, Batavia, IL 60510 USA. NR 2 TC 15 Z9 15 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3573 EP 3576 DI 10.1109/77.919836 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900220 ER PT J AU Dietderich, DR Scanlan, RM Hasegawa, T Aoki, Y Sokolowski, RS Motowidlo, LR AF Dietderich, DR Scanlan, RM Hasegawa, T Aoki, Y Sokolowski, RS Motowidlo, LR TI Critical current variation as a function of transverse stress of Bi-2212 rutherford cables SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Bi-2212; cables; critical current; and stress AB Transverse loading experiments on wire has shown that a significant drop in critical current occurs for stresses greater than 50 MPa, However, many high-energy physics applications require that the Bi2Sr2CaCu2O8 conductor withstand stresses greater than 100 MPa without permanent degradation. Therefore, a study of epoxy impregnated cables, identical to those used in accelerator magnet applications, has been performed. This work presents the first results of Rutherford cables of Bi2Sr2CaCu2O8 with transverse stress. The results show that the cable can withstand stresses up to 60 MPa with a strain of about 0.3 % for the face loading orientation and 100 MPa for the edge loading orientation. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Showa Elect Wire & Cable Co, Kawasaki, Kanagawa, Japan. Intermagnet Gen Corp, Latham, NY 12110 USA. RP Dietderich, DR (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 5 TC 15 Z9 15 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3577 EP 3579 DI 10.1109/77.919837 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900221 ER PT J AU Barzi, E Limon, PJ Yamada, R Zlobin, AV AF Barzi, E Limon, PJ Yamada, R Zlobin, AV TI Study of Nb3Sn strands for Fermilab's high field dipole models SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE critical current; magnetization; Nb3Sn strand; superconducting magnet AB Fermilab is developing II T superconducting dipole magnets for future accelerators based on Nb3Sn conductor. Multifilamentary Nb3Sn strands l mm in diameter produced with the Modified Jelly Roll and Powder-in-Tube technologies were purchased from OST and SMI respectively. They are herein fully characterized by I-c, n-value, residual resistivity ratio, and magnetization, Results of heat treatment optimization studies are also presented for the OST strand. C1 Fermilab, Batavia, IL 60510 USA. RP Barzi, E (reprint author), Fermilab, Batavia, IL 60510 USA. NR 5 TC 27 Z9 27 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3595 EP 3598 DI 10.1109/77.919842 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900226 ER PT J AU Feldmann, DM Reeves, JL Polyanskii, AA Goyal, A Feenstra, R Lee, DF Paranthaman, M Kroeger, DM Christen, DK Babcock, SE Larbalestier, DC AF Feldmann, DM Reeves, JL Polyanskii, AA Goyal, A Feenstra, R Lee, DF Paranthaman, M Kroeger, DM Christen, DK Babcock, SE Larbalestier, DC TI Magneto-optical imaging of transport currents in YBa2Cu3O7-x on RABiTS (TM) SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE coated conductors; grain boundaries; magneto-optical imaging; RABiTS ID SUPERCONDUCTING FILMS; COATED CONDUCTORS; CURRENT FLOW; BICRYSTALS AB Two YBa2CU3O7-x. (YBCO) on RABiTS (TM) conductors with high J(c)(0 T,77 K) values of 2.3 and 2.4 MA/cm(2) were scribed by laser cutting to constrict supercurrent flow. On one of these tracks, magneto-optical (MO) imaging of the self-field produced by a transport current directly demonstrates the percolative nature of the current flow. Using Backscattered Electron Kikuchi Pattern (BEKP) analysis, we have found that Ni grain boundaries (GBs) > 5 degrees generally introduce GBs in the YBCO that have lower J(c) values than the intra-grain. C1 Univ Wisconsin, Ctr Appl Superconduct, Madison, WI 53706 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Feldmann, DM (reprint author), Univ Wisconsin, Ctr Appl Superconduct, Madison, WI 53706 USA. RI Paranthaman, Mariappan/N-3866-2015; Larbalestier, David/B-2277-2008 OI Paranthaman, Mariappan/0000-0003-3009-8531; Larbalestier, David/0000-0001-7098-7208 NR 13 TC 20 Z9 20 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3772 EP 3775 DI 10.1109/77.919885 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900269 ER PT J AU Berenov, AV Marriott, R Foltyn, SR MacManus-Driscoll, JL AF Berenov, AV Marriott, R Foltyn, SR MacManus-Driscoll, JL TI Effect of Ca-doping on grain boundaries and superconducting properties of YBa2Cu3O7-delta SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE critical currents; grain boundaries; SIMS ID THIN-FILMS; DIFFUSION; CRYSTALS AB It is well known that the properties of grain boundaries in YBa2Cu3O7-delta films differ drastically from bulk material. It has been shown both experimentally and theoretically that the grain boundaries in YBa2Cu3O7-delta superconductors are depleted of carriers as compared to the bulk. This depletion leads to weak intergrain links and limits critical currents in superconductor, Recently, the promise for improved grain boundaries has been shown in Ca-doped YBa2Cu3O7-delta thin films and in Ca doped YBa2Cu3O7-delta biaxial grain boundaries. In this study, the effect of Ca-doping of grain boundaries in YBa2Cu3O7-delta films and bulk have been investigated in an attempt to increase hole concentration at the grain boundaries and to improve Jc. Ca-gels were applied to sintered YBa2Cu3O7-delta pellets and thin films. High temperature post-anneals were used to diffuse Ca preferentially into the grain boundaries. The distribution of Ca in the samples was studied by secondary ion mass spectrometry (SIMS), The effect of Ca-doping on Te and Je was studied by VSM. In epitaxial thin film increased Je were found at 40K, but not at 77K. C1 Univ London Imperial Coll Sci Technol & Med, Dept Mat, London SW7 2BP, England. Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Berenov, AV (reprint author), Univ London Imperial Coll Sci Technol & Med, Dept Mat, Prince Consort Rd, London SW7 2BP, England. RI Berenov, Andrey/A-3020-2011 NR 13 TC 9 Z9 9 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3780 EP 3783 DI 10.1109/77.919887 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900271 ER PT J AU Berghuis, P Miller, DJ Kim, DH Gray, KE Feenstra, R Christen, DK AF Berghuis, P Miller, DJ Kim, DH Gray, KE Feenstra, R Christen, DK TI Grain boundary transport properties in YBa2Cu3Ox coated conductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE high temperature superconductors; critical current; grain boundaries ID SUPERCONDUCTING TAPES; CRITICAL CURRENTS; FLUX; FILMS AB Critical current data obtained as a function of magnetic field on an isolated grain boundary (GB) of a coated conductor and two other types of bicrystal GBs of YBa2Cu3Ox show a peak in the critical current and an unusual hysteresis. These results provide support for a new mechanism for enhanced GB critical currents, arising from interactions of GB vortices with pinned Abrikosov vortices in the banks of a GB, as suggested by Gurevich and Cooley. A substantial fraction of this enhancement, which can exceed a factor of ten, also occurs upon surpassing the critical current of the grains after zero field cooling. A bulk GB and thin film GBs show qualitatively identical results. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN USA. RP Berghuis, P (reprint author), Argonne Natl Lab, Div Sci Mat, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3868 EP 3871 DI 10.1109/77.919910 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900293 ER PT J AU Li, Q Zhu, Y Solovyov, VF Wiesmann, HJ Suenaga, M AF Li, Q Zhu, Y Solovyov, VF Wiesmann, HJ Suenaga, M TI Superconducting and microstructural properties of [001] tilt YBa2Cu3O7-delta thick film grain boundaries on SrTiO3 bicrystal substrates SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE critical current; interface phenomena; superconductors AB We present a study of superconducting and microstructural properties of [001] tilt YBa2Cu3O7-delta (YBCO) thick film grain boundaries (GB) on SrTiO3 bicrystal substrates prepared using BaF2 er-situ post deposition reaction process. For a 15 degrees tilt boundary, multiple micro-bridges were patterned across the grain boundary at various locations, A large variation of local critical current density J(c) was observed. Through local microstructural characterization of these GB bridges using transmission electron microscope (TEM), a direct correlation of local GB J(c) with structure is identified. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Li, Q (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Solovyov, Vyacheslav/A-7724-2009 NR 4 TC 2 Z9 2 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3876 EP 3879 DI 10.1109/77.919912 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900295 ER PT J AU McDonald, J Barzi, E AF McDonald, J Barzi, E TI A model for J(c) in granular A-15 superconductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VA DE critical current; Nb3Sn; A-15 superconductors; granular superconductors ID HIGH-TEMPERATURE SUPERCONDUCTORS; GRAIN-BOUNDARIES; PLANAR DEFECTS; NB3SN; FIELD; WIRES AB The A-15 superconductors, specifically Nb3Sn, appear to be the best candidates for the next generation of highfield accelerator magnets. In order for these materials to be successfully employed in future magnets, a better understanding of their transport and magnetization properties must first be obtained. In this paper, a model is presented for the critical current density Je in a granular A-15 superconductor. The model is based on previous results for Josephson-coupled arrays, and anisotropic flux pinning by grain boundaries. It is shown that, contrary to what has previously been thought, the observed field dependence of J(c) can be explained without having to invoke a flux-shearing mechanism. C1 Vector Fields Inc, Aurora, IL 60505 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP McDonald, J (reprint author), Vector Fields Inc, 1700 N Farnsworth Ave, Aurora, IL 60505 USA. EM jmcdonald@vectorfields.com NR 36 TC 7 Z9 7 U1 2 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3884 EP 3887 DI 10.1109/77.919915 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900297 ER PT J AU Askew, TR Cha, YS AF Askew, TR Cha, YS TI Transient response of 50 KiloAmp Y-Ba-Cu-O rings and ring pairs to pulsed magnetic fields SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE fault-current limiter; magnetic diffusion; magnetic shielding; pulsed current testing ID TEMPERATURE SUPERCONDUCTOR TUBE; MELT-PROCESSED YBCO; Y2BACUO5 AB Shielding current limits and magnetic diffusion characteristics have been measured at 77 K in large-grain YBCO rings with oriented microstructures, The samples are surrounded by a drive coil that can achieve magnetic fields in excess of 1 Tesla and induce currents in excess of 50 kA when driven by a current pulse of a few msec duration. Simultaneous magnetic measurements with a Rogowski coil and a Hall probe allow determination of the induced current in the sample and the field in the center of the sample. These measurements show that field penetration occurs in a complex way that includes delays and transient effects caused by magnetic diffusion and sample heating. Dramatic threshold effects are observed that are probably related to a creep-flow transition coupled with local heating effects. Geometric effects are investigated using a single drive coil and a pair of YBCO rings with various spacings, A test geometry equivalent to a simple penetration-type inductive fault current limiter is used; the experimental results are therefore of interest for design and characterization of these devices. C1 Kalamazoo Coll, Kalamazoo, MI 49006 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Askew, TR (reprint author), Kalamazoo Coll, Kalamazoo, MI 49006 USA. NR 13 TC 5 Z9 5 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3947 EP 3950 DI 10.1109/77.919941 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900313 ER PT J AU Trudnowski, DJ McReynolds, WL Johnson, JM AF Trudnowski, DJ McReynolds, WL Johnson, JM TI Real-time very short-term load prediction for power-system automatic generation control SO IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY LA English DT Article DE Kalman prediction; load forecasting; power-system control AB A fundamental objective of a power-system operating and control scheme is to maintain a match between the system's overall real-power load and generation. The automatic generation control (AGC) loop addresses this objective by using system load and electrical frequency samples to periodically update the set-point power for key "swing" generators with a control sample rate ranging from 1 to 10 min. To improve performance, emerging AGC strategies employ a look-ahead control algorithm that requires real-time estimates of the system's future load out to several samples using a one to ten minute sample period (a total typical horizon of 30 to 120 min). We term this very short-term load prediction. This paper describes a strategy for developing a very short-term load predictor using slow and fast Kalman estimators and an hourly forecaster. The Kalman model parameters are determined by matching the frequency response of the estimator to the load residuals, The design strategy is applied to the system operated by the Bonneville Power Administration and specific performance and sensitivity studies are presented. C1 Montana Tech, Dept Engn, Butte, MT 59701 USA. Transmission Operat Bonneville Power Adm, Vancouver, WA 98685 USA. Battelle Pacific NW Natl Lab, Richland, WA 99352 USA. RP Trudnowski, DJ (reprint author), Montana Tech, Dept Engn, Butte, MT 59701 USA. NR 15 TC 51 Z9 53 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1063-6536 J9 IEEE T CONTR SYST T JI IEEE Trans. Control Syst. Technol. PD MAR PY 2001 VL 9 IS 2 BP 254 EP 260 DI 10.1109/87.911377 PG 7 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA 414FV UT WOS:000167656200005 ER PT J AU Monier, C Ren, F Han, J Chang, PC Shul, RJ Lee, KP Zhang, AP Baca, AG Pearton, S AF Monier, C Ren, F Han, J Chang, PC Shul, RJ Lee, KP Zhang, AP Baca, AG Pearton, S TI Simulation of NPN and PNPAlGaN/GaN heterojunction bipolar transistors performances: Limiting factors and optimum design SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article DE AlGaN/GaN HBT; base resistivity; dc current gain; high frequency characteristics; Mg ionization efficiency; quasi-electric field; simulation ID P-TYPE GAN; ALGAN/GAN HETEROSTRUCTURES; ELECTRON-MOBILITY; DIFFUSION LENGTH; LIFETIME; CHARGES AB The performance capabilities of npn and pnp AlGaN/GaN heterojunction bipolar transistors have been investigated by using a drift-diffusion transport model. Numerical results have been employed to study the effect of the p-type Mg doping and its incomplete ionization on device performance. The high base resistance induced by the deep acceptor level is found to be one of the causes of limited current gain values for npn devices. Reasonable improvements of the de current gain beta are observed by realistically reducing the base thickness and consequently the transit time, in accordance with processing Limitations. Base transport enhancement is predicted by the introduction of a quasielectric field in the base. The impact of the base resistivity on high-frequency characteristics is investigated for npn AlGaN/GaN devices. Simulation results reveal the difficulty to achieve decent current gain values at high current density for pnp HBTs in common emitter configuration. Despite the high electron mobility in the n-type base that aids in reducing the base resistance, a preliminary analysis for pnp devices indicates limited rf performances caused by the reduced minority hole transport across the base. 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 Monier, C (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 11 Z9 11 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD MAR PY 2001 VL 48 IS 3 BP 427 EP 432 DI 10.1109/16.906431 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 407CC UT WOS:000167253000006 ER PT J AU Shelton, BS Lambert, DJH Huang, JJ Wong, MM Chowdhury, U Zhu, TG Kwon, HK Liliental-Weber, Z Benarama, M Feng, M Dupuis, RD AF Shelton, BS Lambert, DJH Huang, JJ Wong, MM Chowdhury, U Zhu, TG Kwon, HK Liliental-Weber, Z Benarama, M Feng, M Dupuis, RD TI Selective area growth and characterization of AlGaN/GaN heterojunction bipolar transistors by metalorganic chemical vapor deposition SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article DE aluminum gallium nitride; heterojunction bipolar transistor; regrowth; selective area growth ID GAN; LAYERS; DEVICE AB The selective area growth (SAG) and properties of AlGaN/GaN heterojunction bipolar transistors (HBTs) grown by low-pressure metalorganic chemical vapor deposition (MOCVD) are described and analyzed. Transistors based on group m-nitride material are attractive for high-power and high-temperature applications, Much work has been focused on improving p-type material, as well as heterojunction interfaces. However, there have been very few reports on HBTs operating at room temperature. At this time, current gains for nitride-based HBTs have been limited to similar to 10. Selective area regrowth was applied to the growth of AlGaN/GaN HBTs to analyze its potential advantages as compared to more traditional growth techniques in order to realize improved electrical performance of the devices. C1 EMCORE Corp, Somerset, NJ 08873 USA. Nortel Networks, Wilmington, MA 01887 USA. Univ Illinois, Microelect Lab, Urbana, IL 61801 USA. Univ Texas, Ctr Microelect Res, Austin, TX 78712 USA. Honeywell Labs, Minneapolis, MN 55418 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Shelton, BS (reprint author), EMCORE Corp, 35 Elizabeth Ave, Somerset, NJ 08873 USA. RI Liliental-Weber, Zuzanna/H-8006-2012; Huang, Jian Jang/L-9953-2016 OI Huang, Jian Jang/0000-0002-5761-2177 NR 12 TC 25 Z9 26 U1 2 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD MAR PY 2001 VL 48 IS 3 BP 490 EP 494 DI 10.1109/16.906441 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 407CC UT WOS:000167253000016 ER PT J AU Muljadi, E Hess, HL Thomas, K AF Muljadi, E Hess, HL Thomas, K TI Zero sequence method for energy recovery from a variable-speed wind turbine generator SO IEEE TRANSACTIONS ON ENERGY CONVERSION LA English DT Article DE DC-AC power conversion; induction generators; inverters; power conversion; wind energy; wind power generation AB An innovative power conversion system to convert energy from a variable-frequency wind-powered induction generator to a fixed frequency output. A standard six-switch de link Current Regulated Pulse Width Modulated (CRPWM) inverter is simultaneously modulated with two current components. A three-phase balanced current component at the induction generator's optimum operating frequency transfers energy from the generator to the converter. A single phase zero sequence current component at a fixed 60 Hz frequency transfers energy from the converter through a zero sequence filter to the load. Unity power factor output is shown both in simulation and experiment, though any arbitrary power factor output may be readily commanded. Maximum power capture for a variable-speed wind turbine is achieved using proven control techniques. This method uses only half of the active power switching devices of conventional conversion methods. Simulation and experimental verification are shown. C1 Natl Renewable Energy Lab, Golden, CO USA. Univ Idaho, Moscow, ID 83843 USA. Walla Walla Coll, Walla Walla, WA USA. RP Muljadi, E (reprint author), Natl Renewable Energy Lab, Golden, CO USA. NR 6 TC 7 Z9 8 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8969 J9 IEEE T ENERGY CONVER JI IEEE Trans. Energy Convers. PD MAR PY 2001 VL 16 IS 1 BP 99 EP 103 DI 10.1109/60.911411 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA 413AJ UT WOS:000167587500017 ER PT J AU Ding, CHQ AF Ding, CHQ TI An optimal index reshuffle algorithm for multidimensional arrays and its applications for parallel architectures SO IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS LA English DT Article DE multidimensional arrays; index reshuffle; vacancy tracking cycles; global exchange; dynamic remapping ID COMMUNITY CLIMATE MODEL; DESIGN AB Reshuffling elements of a multidimensional array according to an index operation traditionally requires an auxiliary buffer of the same size as the original array. Here, we describe a new in-place algorithm using vacancy tracking cycles with minimum memory access which eliminates the buffer array and the related copy-back, speeding up the reshuffle significantly for large arrays. The algorithm can be paralleiized using a multithread approach on shared-memory multiprocessor computers. On distributed-memory multiprocessor computers, the index reshuffle of distributed multidimensional arrays amounts to a remapping of processor domains and is carried out using the in-place local algorithm combined with a global exchange algorithm. Implementation and test results on GRAY T3E and IBM SP indicate the effectiveness of the algorithm. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC Div, Berkeley, CA 94720 USA. RP Ding, CHQ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC Div, Berkeley, CA 94720 USA. NR 12 TC 7 Z9 7 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1045-9219 J9 IEEE T PARALL DISTR JI IEEE Trans. Parallel Distrib. Syst. PD MAR PY 2001 VL 12 IS 3 BP 306 EP 315 DI 10.1109/71.914776 PG 10 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 418CY UT WOS:000167873200006 ER PT J AU Cao, C Kevrekidis, IG Titi, ES AF Cao, C Kevrekidis, IG Titi, ES TI Numerical criterion for the stabilization of steady states of the Navier-Stokes equations SO INDIANA UNIVERSITY MATHEMATICS JOURNAL LA English DT Article; Proceedings Paper CT Conference on Nonlinear Problems in Applied Sciences CY SEP 15-17, 2000 CL BLOOMINGTON, IN ID APPROXIMATE INERTIAL MANIFOLDS; FINITE-DIMENSIONAL CONTROL; KURAMOTO-SIVASHINSKY EQUATION; DISTRIBUTED PARAMETER-SYSTEMS; NONLINEAR GALERKIN METHODS; FEEDBACK-CONTROL; MODEL-REDUCTION; DIFFERENTIAL-EQUATIONS; STATIONARY SOLUTIONS; FLUID-DYNAMICS AB This paper introduces an explicit numerical criterion for the stabilization of steady state solutions of the Navier-Stokes equations (NSE) with linear feedback control. Given a linear feedback controller that stabilizes a steady state solution to the closed-loop standard Galerkin (or nonlinear Galerkin) NSE discretization, it is shown that, if the number of modes involved in the computation is large enough, this controller stabilizes a nearby steady state of the closed-loop NSE. We provide an explicit estimate, in terms of the physical parameters, for the number of modes required in order for this criterion to hold. Moreover, we provide an estimate for the distance between the stabilized numerical steady state and the actually stabilized steady state of the closed-loop Navier-Stokes equations. More accurate approximation procedures, based on the concept of postprocessing the Galerkin results, are also presented. All the criterion conditions are imposed on the computed numerical solution, and no a priori knowledge is required about the steady state solution of the full PDE. This criterion holds for a large class of unbounded linear feedback operators and can be slightly modified to include certain nonlinear parabolic systems such as reaction-diffusion systems. C1 Univ Calif Irvine, Dept Math, Irvine, CA 92697 USA. Princeton Univ, Dept Chem Engn, Princeton, NJ 08544 USA. Univ Calif Irvine, Dept Mech & Aerosp Engn, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Math, Irvine, CA 92697 USA. RP Cao, C (reprint author), Los Alamos Natl Lab, Ctr Nonlinear Studies, MS-258, Los Alamos, NM 87545 USA. EM ccao@math.uci.edu NR 76 TC 4 Z9 4 U1 0 U2 2 PU INDIANA UNIV MATH JOURNAL PI BLOOMINGTON PA SWAIN HALL EAST 222, BLOOMINGTON, IN 47405 USA SN 0022-2518 J9 INDIANA U MATH J JI Indiana Univ. Math. J. PD SPR PY 2001 VL 50 SI SI BP 37 EP 96 PG 60 WC Mathematics SC Mathematics GA 480ZV UT WOS:000171494400003 ER PT J AU Concus, P Finn, R McCuan, J AF Concus, P Finn, R McCuan, J TI Liquid bridges, edge blobs, and Scherk-type capillary surfaces SO INDIANA UNIVERSITY MATHEMATICS JOURNAL LA English DT Article DE capillary surface; stability; contact angle; liquid bridge; mean curvature ID CONTACT ANGLES; MEAN-CURVATURE; STABILITY; PARALLEL; BOUNDARY; BEHAVIOR; WEDGES; PLANES; CORNER; DROPS AB It is shown that, with the exception of very particular cases, any tubular liquid bridge configuration joining parallel plates in the absence of gravity must change discontinuously with tilting of the plates, thereby proving a conjecture of Concus and Finn [Phys. Fluids 10 (1998) 39-43]. Thus the stability criteria that have appeared previously in the literature, which take no account of such tilting, are to some extent misleading. Conceivable configurations of the liquid mass following a plate tilting are characterized, and conditions are presented under which stable drops in wedges, with disk-type or tubular free bounding surfaces, can be expected. As a corollary of the study, a new existence theorem for H-graphs over a square with discontinuous data is obtained. The resulting surfaces can be interpreted as generalizations of the Scherk minimal surface in two senses: (a) the requirement of zero mean curvature is weakened to constant mean curvature, and (b) the boundary data of the Scherk surface, which alternate between the constants +infinity and -infinity on adjacent sides of a square, are replaced by capillary data alternating between two constant values, restricted by a geometrical criterion. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. RP Concus, P (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 47 TC 17 Z9 18 U1 2 U2 12 PU INDIANA UNIV MATH JOURNAL PI BLOOMINGTON PA SWAIN HALL EAST 222, BLOOMINGTON, IN 47405 USA SN 0022-2518 J9 INDIANA U MATH J JI Indiana Univ. Math. J. PD SPR PY 2001 VL 50 IS 1 BP 411 EP 441 DI 10.1512/iumj.2001.50.1849 PG 31 WC Mathematics SC Mathematics GA 480ZW UT WOS:000171494500006 ER PT J AU Benson, JM Tibbetts, BM Thrall, KD Springer, DL AF Benson, JM Tibbetts, BM Thrall, KD Springer, DL TI Uptake, tissue distribution, and fate of inhaled carbon tetrachloride: Comparison of rat, mouse, and hamster SO INHALATION TOXICOLOGY LA English DT Article ID INHALATION; METABOLISM; PHARMACOKINETICS; ELIMINATION; EXPOSURES AB Carbon tetrachloride is hepatotoxic in rats, mice, and hamsters. However, rats are less sensitive to the hepatotoxic effects of CCl4 than the other two species. The purpose of this study was to compare the uptake, tissue distribution, and elimination of CCl4 by these three rodent species. Groups of 20 F344/Crl BR rats, B6C3F(1) mice, and Syrian hamsters were exposed by nose-only inhalation for 4 h to 20 ppm C-14-labeled CCl4. The fate of C-14 was followed in tissues, excreta, and exhaled breath for 48 h after the exposure. At the end of the exposure, concentrations of CCl4 equivalents ( CE) in tissue were highest in liver of rats and mice, but highest in fat for rats. The liver received the highest dose of CCl4 equivalents with the following species ranking: mouse > hamster > rat. Patterns of CE elimination were species and tissue dependent, with the majority of elimination occurring within 48 h after exposure. Rats eliminated less radioactivity associated with metabolism ( (CO2)-C-14, urine and feces) and more radioactivity associated with parent compound ( exhaled activity trapped on charcoal) than did mice or hamsters. The results indicate that ranking of species sensitivity to the hepatotoxic effects of inhaled CCl4 correlates with CE dose to liver and with the ability to metabolize CCl4. C1 Lovelace Resp Res Inst, Albuquerque, NM 87185 USA. Pacific NW Natl Lab, Mol Biosci Dept, Washington, DC USA. RP Benson, JM (reprint author), Lovelace Resp Res Inst, POB 5890, Albuquerque, NM 87185 USA. NR 15 TC 4 Z9 4 U1 0 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0895-8378 J9 INHAL TOXICOL JI Inhal. Toxicol. PD MAR PY 2001 VL 13 IS 3 BP 207 EP 217 PG 11 WC Toxicology SC Toxicology GA 405QD UT WOS:000167169800002 PM 11295857 ER PT J AU Rawn, CJ Schneibel, JH Hoffmann, CM Hubbard, CR AF Rawn, CJ Schneibel, JH Hoffmann, CM Hubbard, CR TI The crystal structure and thermal expansion of Mo5SiB2 SO INTERMETALLICS LA English DT Article DE molybdenum silicides; thermal properties; crystallography ID SILICIDES; CREEP AB Mo5SiB2 (T2). synthesized with B-11, was studied using high temperature neutron powder diffraction. This ternary compound crystallizes with a tetragonal unit cell. space group 14/mcm. with room temperature lattice parameters a = 6.0271(3) c = 11.0671(7) Angstrom. The structural refinement reveals that B substitutes for a minor amount of Si for a formula of Mo5Si0.89B2.11. The refined lattice parameters studied as a function of temperature give average thermal expansion coefficients along the a and c-axes, (7.9 +/-0.1)x10-(6) K-1 and (7.5+/-0.2)x10(6) K-1, respectively. The thermal expansion of Mo5SiB2 is, therefore, nearly isotropic. A more detailed evaluation shows that the thermal expansion coefficient. as well as the thermal expansion anisotropy, vary with temperature. Published by Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Rawn, CJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 26 TC 45 Z9 49 U1 0 U2 11 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0966-9795 J9 INTERMETALLICS JI Intermetallics PD MAR PY 2001 VL 9 IS 3 BP 209 EP 216 DI 10.1016/S0966-9795(00)00113-8 PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 413QF UT WOS:000167622700004 ER PT J AU Chow, E AF Chow, E TI Parallel implementation and practical use of sparse approximate inverse preconditioners with a priori sparsity patterns SO INTERNATIONAL JOURNAL OF HIGH PERFORMANCE COMPUTING APPLICATIONS LA English DT Article ID DENSE LINEAR-SYSTEMS AB This paper describes and tests a parallel message-passing code for constructing sparse approximate inverse preconditioners using Frobenius norm minimization. The sparsity patterns of the preconditioners are chosen as patterns of powers of sparsified matrices. Sparsification is necessary when powers of a matrix have a large number of nonzeros, making the approximate inverse computation expensive. For our test problems, the minimum solution time is achieved with approximate inverses with less than twice the number of nonzeros of the original matrix. Additional accuracy is not compensated by the increased cost per iteration. The results lead to further understanding of how to use these methods and how well these methods work in practice. in addition, this paper describes programming techniques required for high performance, including one-sided communication, local coordinate numbering, and load repartitioning. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Chow, E (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, L-560,Box 808, Livermore, CA 94551 USA. NR 38 TC 46 Z9 47 U1 0 U2 0 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 1094-3420 J9 INT J HIGH PERFORM C JI Int. J. High Perform. Comput. Appl. PD SPR PY 2001 VL 15 IS 1 BP 56 EP 74 DI 10.1177/109434200101500106 PG 19 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA 416PW UT WOS:000167790200006 ER PT J AU Wise, MG McArthur, JV Shimkets, LJ AF Wise, MG McArthur, JV Shimkets, LJ TI Methylosarcina fibrata gen. nov., sp nov and Methylosarcina quisquiliarum sp nov., novel type I methanotrophs SO INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY LA English DT Article DE Methylosarcina gen. nov.; methanotrophs; landfills ID METHANE-UTILIZING BACTERIA; TRICHLOROETHYLENE OXIDATION; FAMILY METHYLOCOCCACEAE; RENATURATION RATES; MAXIMUM-LIKELIHOOD; PHYLOGENETIC TREES; DNA HYBRIDIZATION; SEQUENCES; CHROMATOGRAPHY; MONOOXYGENASE AB Two novel species of obligate methane-oxidizing bacteria, isolated from landfill soil, were characterized. Both strains were unusual in that some that some members of the population grew in irregularly shaped, refractile cell packets that resembled sarcina-like clusters. Electron microscopy revealed that the cell packets were covered with a slime layer and the cells contained many large granular inclusion bodies. The individual cells of each strain were sometimes motile and had differing morphologies. Isolate AML-C10(T) was always coccoidal in shape, and the cells were covered with extracellular fibrils. Isolate AML-D4(T) was pleomorphic, changing from rod to coccal form, sometimes exhibiting an unusual fusiform morphology. AML-D4(T) lacked the extensive fibrillar matrix observed with AML-C10(T). Both strains utilized only methane and methanol as carbon sources. In stationary phase, the cells of each strain swelled in size and formed cysts. Aside from morphological differences, strains could also be distinguished from each other by cellular protein patterns, as well as by temperature and pH tolerances. 16S rDNA phylogenetic analysis showed that these are type I methanotrophs (family: Methylococcaceae) most closely related to the Methylobacter/Methylomicrobium clade, although they form a monophyletic grouping supported by moderately high bootstrap values. By 16S rDNA database searches, the most similar species to both isolates were Methylobacter spp. However, partial particulate methane monooxygenase sequence analysis suggested that these bacteria might be more closely related to Methylomicrobium than Methylobacter. Furthermore, cellular fatty acid profiles of the strains more closely resemble those of Methylomicrobium, although the absence of significant levels of 16:1 omega 5c argues for the uniqueness of these two strains. On the basis of the results described here, it is proposed that a new genus should be created, Methylosarcina gen. nov., harbouring two species, Methylosarcina fibrata sp. nov. (type species) and Methylosarcina quisquiliarum sp, nov. The type strains are AML-C10(T)(= ATCC 700909(T) = DSM 13736(T)) and AML-D4(T)(= ATCC 700908(T) = DSM 13737(T)), respectively. C1 Univ Georgia, Dept Microbiol, Athens, GA 30602 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Shimkets, LJ (reprint author), Univ Georgia, Dept Microbiol, Athens, GA 30602 USA. NR 38 TC 50 Z9 56 U1 0 U2 11 PU SOC GENERAL MICROBIOLOGY PI READING PA MARLBOROUGH HOUSE, BASINGSTOKE RD, SPENCERS WOODS, READING RG7 1AE, BERKS, ENGLAND SN 1466-5026 J9 INT J SYST EVOL MICR JI Int. J. Syst. Evol. Microbiol. PD MAR PY 2001 VL 51 BP 611 EP 621 PN 2 PG 11 WC Microbiology SC Microbiology GA 413QD UT WOS:000167622500038 PM 11321107 ER PT J AU Fitzpatrick, A AF Fitzpatrick, A TI Soviet scientists in the nuclear age: A memoir. SO ISIS LA English DT Book Review C1 George Washington Univ, Ctr Hist Recent Sci, Washington, DC 20052 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Fitzpatrick, A (reprint author), George Washington Univ, Ctr Hist Recent Sci, Washington, DC 20052 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0021-1753 J9 ISIS JI Isis PD MAR PY 2001 VL 92 IS 1 BP 211 EP 212 DI 10.1086/385138 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA 445ZT UT WOS:000169489000102 ER PT J AU Dahl, PF AF Dahl, PF TI The radiance of France: Nuclear power and national identity after World War II. SO ISIS LA English DT Book Review C1 Lawrence Berkeley Lab, Berkeley, CA USA. RP Dahl, PF (reprint author), Lawrence Berkeley Lab, Berkeley, CA USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0021-1753 J9 ISIS JI Isis PD MAR PY 2001 VL 92 IS 1 BP 212 EP 213 DI 10.1086/385140 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA 445ZT UT WOS:000169489000104 ER PT J AU Matsuura, D Kanemitsu, Y Kushida, T White, CW Budai, JD Meldrum, A AF Matsuura, D Kanemitsu, Y Kushida, T White, CW Budai, JD Meldrum, A TI Photoluminescence dynamics of CdS nanocrystals fabricated by sequential ion implantation SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT International Symposium on Formation, Physics and Device Application of Quantum Dot Structures (QDS 2000) CY SEP 10-14, 2000 CL HOKKAIDO UNIV, SAPPORO, JAPAN SP Minist Educ, Sci, Sports & Culture HO HOKKAIDO UNIV DE nanocrystal; exciton; CdS; ion implantation; photoluminescence ID GAAS NANOCRYSTALS; BEAM SYNTHESIS; MATRICES AB We have studied photoluminescence (PL) dynamics of US nanocrystals fabricated by sequential Cd+ and S+ ion implantation into Al2O3 matrices. The PL spectrum and PL decay dynamics of US nanocrystals are sensitive to the measurement temperature. This is because excitons trapped at shallow localized states are thermally excited to the high-energy state at high temperatures. Two PL bands appear near the absorption edge at elevated temperatures near 100 K. From time-resolved PL spectra and the PL decay dynamics, it is concluded that the observed PL bands near the absorption edge are due to free excitons and excitons trapped at shallow localized states. The PL mechanism in US nanocrystals is discussed. C1 Nara Inst Sci & Technol, Grad Sch Mat Sci, Nara 6300101, Japan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. RP Kanemitsu, Y (reprint author), Nara Inst Sci & Technol, Grad Sch Mat Sci, Nara 6300101, Japan. RI Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 11 TC 8 Z9 10 U1 0 U2 3 PU INST PURE APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG, 4-24-8 SHINBASHI, MINATO-KU TOKYO, 105-004, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PD MAR PY 2001 VL 40 IS 3B BP 2092 EP 2094 DI 10.1143/JJAP.40.2092 PG 3 WC Physics, Applied SC Physics GA 468RH UT WOS:000170771600139 ER PT J AU Vetrano, JS AF Vetrano, JS TI Superplasticity: Mechanisms and applications SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Vetrano, JS (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 0 TC 1 Z9 1 U1 0 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD MAR PY 2001 VL 53 IS 3 BP 22 EP 22 DI 10.1007/s11837-001-0173-x PG 1 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 410MD UT WOS:000167443000005 ER PT J AU Conry, MJ Dunne, B AF Conry, MJ Dunne, B TI Influence of number and timing of fungicide applications on the yield and quality of early and later-sown spring malting barley grown in the south-east of Ireland SO JOURNAL OF AGRICULTURAL SCIENCE LA English DT Article ID NITROGEN; RATES AB Eighteen experiments were carried out over a B-year period (1989-94) on three different soil types to compare the effects of a broad-spectrum fungicide, applied as 1-, 2- or 3-spray programmes at different growth stages, to control foliar diseases on early and later-sown Blenheim malting barley. Powdery mildew, caused by Erysiphe graminis (Blumeria graminis) f. sp. hordei, was the dominant disease in all 6 years. Sowing date had a major effect on grain yield and ex-farm quality of the malting barley. The earlier-sown treatments gave significantly greater yield than the later-sown in 13 of the experiments, and significantly lower grain N concentrations and screenings (small grains < 2.2 mm) in 14 and 16 of them, respectively. Early and more frequent fungicide applications improved grain yield and reduced grain screenings but had no significant effect on grain N. Early-applied fungicide (i.e. before GS 33) was generally the most effective in controlling disease, increasing yield and reducing screenings. The magnitude of the response depended on disease severity. In those years when disease was low on the early-sown crops (1989, 1991 and 1994), the early-applied 1-spray programme and 2-spray programmes increased grain yields by relatively small amounts in both early and late-sown crops. In the other 3 years (1990, 1992 and 1993), when disease severity was greater, the early-applied 1-spray programme and 2-spray programmes gave much greater grain yield increments on both early and late sowings. The 3-spray fungicide programme gave the greatest yields in most of the experiments but they were not significantly greater than the best of all the: other treatments. Grain screenings were reduced by fungicide applications in both early and late-sown crops, but the early-applied 1-spray programme and 2-spray programmes were generally the most effective in reducing screenings. C1 TEAGASC, Crops Res Ctr, Carlow, Ireland. RP Conry, MJ (reprint author), TEAGASC, Crops Res Ctr, Oak Pk, Carlow, Ireland. NR 20 TC 3 Z9 3 U1 3 U2 6 PU CAMBRIDGE UNIV PRESS PI PORT CHESTER PA 110 MIDLAND AVE, PORT CHESTER, NY 10573-4930 USA SN 0021-8596 J9 J AGR SCI JI J. Agric. Sci. PD MAR PY 2001 VL 136 BP 159 EP 167 DI 10.1017/S0021859601008620 PN 2 PG 9 WC Agriculture, Multidisciplinary SC Agriculture GA 411VK UT WOS:000167519800003 ER PT J AU Gonzalez, GB Cohen, JB Hwang, JH Mason, TO Hodges, JP Jorgensen, JD AF Gonzalez, GB Cohen, JB Hwang, JH Mason, TO Hodges, JP Jorgensen, JD TI Neutron diffraction study on the defect structure of indium-tin-oxide SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID RAY ABSORPTION-SPECTROSCOPY; DOPED IN2O3 FILMS; THIN-FILMS; X-RAY; ELECTRICAL-PROPERTIES; ITO AB The defect structure of undoped and Sn-doped In2O3 (ITO) materials was studied by preparing powders under different processing environments and performing neutron powder diffraction. The effect of tin doping and oxygen partial pressure was determined. Structural information was obtained by analyzing neutron powder diffraction data using the Rietveld method. The results include positions of the atoms, their thermal displacements, the fractional occupancy of the interstitial oxygen site, and the fractional occupancies of Sn on each of the two nonequivalent cation sites. The tin cations show a strong preference for the b site versus the d site. The measured electrical properties are correlated with the interstitial oxygen populations, which agree with the proposed models for reducible (2Sn(In)(.)O(i)")(x) and nonreducible (2Sn(In)(.)3O(O)O(i)")(x) defect clusters. (C) 2001 American Institute of Physics. C1 Northwestern Univ, Robert R McCormick Sch Engn & Appl Sci, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Mason, TO (reprint author), Northwestern Univ, Robert R McCormick Sch Engn & Appl Sci, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RI Mason, Thomas/B-7528-2009; Hodges, Jason/K-1421-2013; OI Hodges, Jason/0000-0003-3016-4578 NR 22 TC 86 Z9 86 U1 2 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2001 VL 89 IS 5 BP 2550 EP 2555 PG 6 WC Physics, Applied SC Physics GA 404ZP UT WOS:000167133000009 ER PT J AU Zhang, QM Xu, HS Fang, F Cheng, ZY Xia, F You, H AF Zhang, QM Xu, HS Fang, F Cheng, ZY Xia, F You, H TI Critical thickness of crystallization and discontinuous change in ferroelectric behavior with thickness in ferroelectric polymer thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID VINYLIDENE FLUORIDE; PIEZOELECTRIC PROPERTIES; TRIFLUOROETHYLENE COPOLYMERS AB We report on the observation of the critical thickness of crystallization of ferroelectric poly(vinylidene fluoride-trifluoroethylene) copolymer thin films, which were solution spun cast on platinum coated silicon wafer. The effect occurs at about 100 nm thickness, which is significantly above any currently known spatial dimensions of the polymer, so that for films at thickness below about 100 nm, the crystallization process is strongly hindered, resulting in a low crystallinity in these films. This low crystallinity leads to a large and discontinuous change of the dielectric constant and ferroelectric polarization in the films below the critical thickness. (C) 2001 American Institute of Physics. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Penn State Univ, Dept Elect Engn, University Pk, PA 16802 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Zhang, QM (reprint author), Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. RI Cheng, Zhongyang (Z.-Y.)/A-9841-2008; You, Hoydoo/A-6201-2011 OI Cheng, Zhongyang (Z.-Y.)/0000-0001-7209-7380; You, Hoydoo/0000-0003-2996-9483 NR 26 TC 107 Z9 109 U1 1 U2 35 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2001 VL 89 IS 5 BP 2613 EP 2616 DI 10.1063/1.1344585 PG 4 WC Physics, Applied SC Physics GA 404ZP UT WOS:000167133000019 ER PT J AU Lo, CCH Snyder, JE Leib, J Chen, R Kriegermeier-Sutton, B Kramer, MJ Jiles, DC Kief, MT AF Lo, CCH Snyder, JE Leib, J Chen, R Kriegermeier-Sutton, B Kramer, MJ Jiles, DC Kief, MT TI Magnetic force microscopy study of magnetization reversal in sputtered FeSiAl(N) films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SENDUST FILMS; SOFT AB The magnetization reversal in a series of rf-sputtered FeSiAl(N) films has been studied using magnetic force microscopy. A system has been developed which has the capability to image domain structure while an in-plane magnetic field is applied in situ. All films exhibited a stripe domain structure in zero applied field which was indicative of a perpendicular component of domain magnetization which alternates in sign. All films showed a similar sequence of magnetization processes: on reducing the applied field from saturation a fine stripe domain structure nucleated and then coarsened as the field was decreased to zero. Local switching of domain contrast was observed along the steepest part of the hysteresis loop as the perpendicular component reversed. As the reverse field was increased toward saturation, the stripe domains disintegrated into smaller regions. This observation is consistent with an interpretation that the domain magnetization rotated locally into the sample plane. The saturation field and the film stress exhibited similar trends with nitrogen partial pressure. The results suggest that the perpendicular anisotropy that caused the formation of the stripe domain structure could be induced by the film stress via magnetoelastic coupling. (C) 2001 American Institute of Physics. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ, Dept Elect & Comp Engn, Ames, IA 50011 USA. Seagate Technol, Minneapolis, MN 55435 USA. RP Lo, CCH (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. RI Jiles, David/H-9548-2012 NR 12 TC 4 Z9 5 U1 0 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2001 VL 89 IS 5 BP 2868 EP 2872 DI 10.1063/1.1344579 PG 5 WC Physics, Applied SC Physics GA 404ZP UT WOS:000167133000059 ER PT J AU Krauss, AR Auciello, O Ding, MQ Gruen, DM Huang, Y Zhirnov, VV Givargizov, EI Breskin, A Chechen, R Shefer, E Konov, V Pimenov, S Karabutov, A Rakhimov, A Suetin, N AF Krauss, AR Auciello, O Ding, MQ Gruen, DM Huang, Y Zhirnov, VV Givargizov, EI Breskin, A Chechen, R Shefer, E Konov, V Pimenov, S Karabutov, A Rakhimov, A Suetin, N TI Electron field emission for ultrananocrystalline diamond films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID VAPOR-DEPOSITED-DIAMOND; NANOCRYSTALLINE DIAMOND; MICROWAVE PLASMAS; GRAIN-BOUNDARIES; THIN-FILMS; GROWTH; EMITTERS; FABRICATION; MICROSCOPY; SURFACE AB Ultrananocrystalline diamond (UNCD) films 0.1-2.4 mum thick were conformally deposited on sharp single Si microtip emitters, using microwave CH4-Ar plasma-enhanced chemical vapor deposition in combination with a dielectrophoretic seeding process. Field-emission studies exhibited stable, extremely high (60-100 muA/tip) emission current, with little variation in threshold fields as a function of film thickness or Si tip radius. The electron emission properties of high aspect ratio Si microtips, coated with diamond using the hot filament chemical vapor deposition (HFCVD) process were found to be very different from those of the UNCD-coated tips. For the HFCVD process, there is a strong dependence of the emission threshold on both the diamond coating thickness and Si tip radius. Quantum photoyield measurements of the UNCD films revealed that these films have an enhanced density of states within the bulk diamond band gap that is correlated with a reduction in the threshold field for electron emission. In addition, scanning tunneling microscopy studies indicate that the emission sites from UNCD films are related to minima or inflection points in the surface topography, and not to surface asperities. These data, in conjunction with tight binding pseudopotential calculations, indicate that grain boundaries play a critical role in the electron emission properties of UNCD films, such that these boundaries: (a) provide a conducting path from the substrate to the diamond-vacuum interface, (b) produce a geometric enhancement in the local electric field via internal structures, rather than surface topography, and (c) produce an enhancement in the local density of states within the bulk diamond band gap. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Beijing Vacuum Elect Res Inst, Beijing 100016, Peoples R China. Semicond Res Corp, Res Triangle Pk, NC 27709 USA. Russian Acad Sci, Inst Cristallog, Moscow 117333, Russia. Weizmann Inst Sci, IL-76100 Rehovot, Israel. Russian Acad Sci, Inst Gen Phys, Moscow, Russia. Moscow State Univ, Dept Nucl Engn, Moscow, Russia. RP Krauss, AR (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Rakhimov, Alexander/D-8469-2012; BRESKIN, AMOS/K-1549-2012 NR 37 TC 145 Z9 152 U1 1 U2 26 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2001 VL 89 IS 5 BP 2958 EP 2967 DI 10.1063/1.1320009 PG 10 WC Physics, Applied SC Physics GA 404ZP UT WOS:000167133000071 ER PT J AU Zheng, Y Lau, SS Hochbauer, T Misra, A Verda, R He, XM Nastasi, M Mayer, JW AF Zheng, Y Lau, SS Hochbauer, T Misra, A Verda, R He, XM Nastasi, M Mayer, JW TI Orientation dependence of blistering in H-implanted Si SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID N-TYPE SILICON; HYDROGEN; STRESS; SMART-CUT(R); HISTORY; BORON AB The orientation effect on blistering phenomenon in H implanted Si was studied for (100), (111), and (110) Si wafers. It was found that substrate orientation has no observable effects on the underlying blistering mechanisms. Furthermore, the implantation damage, Si-H complex formation in as-implanted samples and surface roughness of the transferred layer appeared to be unaffected by the orientation. However, the blistering kinetics are orientation dependent, with (100) Si having the fastest blistering rate, and (110) Si the slowest. This dependence was attributed to the different density of ruptured Si-Si bonds of different orientations. The magnitude of the observed in-plane compressive stress in the H-implanted Si wafers is rationalized in terms of the formation of platelets in the samples. (C) 2001 American Institute of Physics. C1 Univ Calif San Diego, Dept Elect & Comp Engn, La Jolla, CA 92093 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Arizona State Univ, Ctr Solid State Sci, Tempe, AZ 85287 USA. RP Zheng, Y (reprint author), Univ Calif San Diego, Dept Elect & Comp Engn, La Jolla, CA 92093 USA. RI Misra, Amit/H-1087-2012 NR 26 TC 53 Z9 56 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2001 VL 89 IS 5 BP 2972 EP 2978 DI 10.1063/1.1334921 PG 7 WC Physics, Applied SC Physics GA 404ZP UT WOS:000167133000073 ER PT J AU Ma, Q Moldovan, N Mancini, DC Rosenberg, RA AF Ma, Q Moldovan, N Mancini, DC Rosenberg, RA TI Wet etching of GaAs using synchrotron radiation x rays SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SELECTIVE-AREA DEPOSITION; III-V-SEMICONDUCTORS; LITHOGRAPHY; OXIDATION AB The results of room-temperature wet etching of GaAs using synchrotron-radiation x rays are described. Under x-ray illumination, etching occurs on the n-GaAs surface in contact with an acid or base solution or even deionized water. The etching process is studied as functions of the electrolytes, their concentration, semiconductor doping level, and x-ray intensity and energy. The etching mechanism is determined to be primarily electrochemical in nature, but the x-ray radiation chemistry plays a role in the etching. Smoothly etched surfaces are achievable with a root-mean-square surface roughness of 0.7-2.0 nm. We also found that the etching rate increases substantially with the ratio of the sample size to the x-ray exposure size. This is accounted for by the rate-limiting effect on the charge transfer across the semiconductor-electrolyte junction. The chemistry of etched surfaces is studied using x-ray photoelectron spectroscopy and compared to that of as-received surfaces. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Ma, Q (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Rosenberg, Richard/K-3442-2012 NR 35 TC 8 Z9 9 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2001 VL 89 IS 5 BP 3033 EP 3040 DI 10.1063/1.1345859 PG 8 WC Physics, Applied SC Physics GA 404ZP UT WOS:000167133000081 ER PT J AU Kato-Weinstein, J Stauber, AJ Orner, GA Thrall, BD Bull, RJ AF Kato-Weinstein, J Stauber, AJ Orner, GA Thrall, BD Bull, RJ TI Differential effects of dihalogenated and trihalogenated acetates in the liver of B6C3F1 mice SO JOURNAL OF APPLIED TOXICOLOGY LA English DT Article DE dibromoacetate; bromochloroacetate; bromodichloroacetate; glycogen; insulin; peroxisome proliferator; cell proliferation; B6C3F1 mice ID DICHLOROACETIC ACID; TRICHLOROACETIC-ACID; PEROXISOME PROLIFERATION; DIABETES-MELLITUS; CELL-PROLIFERATION; DRINKING-WATER; MOUSE-LIVER; IN-VIVO; CARCINOGENICITY; CANCER AB Haloacetates are produced in the chlorination of drinking water in the range 10-100 mug l(-1). As bromide concentrations increase, brominated haloacetates such as bromodichloroacetate (BDCA), bromochloroacetate (BCA) and dibromoacetate (DBA) appear at higher concentrations than the chlorinated haloacetates: dichloroacetate (DCA) or trichloroacetate (TCA), Both DCA and TCA differ in their hepatic effects; TCA produces peroxisome proliferation as measured by increases in cyanide-insensitive acyl CoA oxidase activity, whereas DCA increases glycogen concentrations. In order to determine whether the brominated haloacetates DBA, BCA and BDCA resemble DCA or TCA more closely, mice were administered DBA, BCA and BDCA in the drinking water at concentrations of 0.2-3 g l(-1). Both BCA and DBA caused liver glycogen accumulation to a similar degree as DCA (12 weeks). The accumulation of glycogen occurred in cells scattered throughout the acinus in a pattern very similar to that observed in control mice. In contrast, TCA and low concentrations of BDCA (0.3 g l(-1)) reduced liver glycogen content, especially in the central lobular region, The high concentration of BDCA (3 g l(-1)) produced a pattern of glycogen distribution similar to that in DCA-treated and control mice. This effect with a high concentration of BDCA may be attributable to the metabolism of BDCA to DCA. All dihaloacetates reduced serum insulin levels, Conversely, trihaloacetates had no significant effects on serum insulin levels. Dibromoacetate was the only brominated haloacetate that consistently increased acyl-CoA oxidase activity and rates of cell replication in the liver. These results further distinguish the effects of the dihaloacetates from those of peroxisome proliferators like TCA. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Washington State Univ, Coll Pharm, Pharmacol Toxicol Program, Pullman, WA 99164 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bull, RJ (reprint author), 1928 Meadows Dr N, Richland, WA 99352 USA. RI Orner, Gayle/F-6876-2013 OI Orner, Gayle/0000-0002-4812-5297 FU NIEHS NIH HHS [R01-ES04648] NR 44 TC 13 Z9 13 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0260-437X J9 J APPL TOXICOL JI J. Appl. Toxicol. PD MAR-APR PY 2001 VL 21 IS 2 BP 81 EP 89 DI 10.1002/jat.717 PG 9 WC Toxicology SC Toxicology GA 418WE UT WOS:000167916500001 PM 11288130 ER PT J AU Longmire, JL Roach, JL Malthie, M White, PS Tatum, OL Makova, KD Hahn, DC AF Longmire, JL Roach, JL Malthie, M White, PS Tatum, OL Makova, KD Hahn, DC TI Tetranucleotide microsatellite markers for the brown-headed Cowbird Molothrus ater SO JOURNAL OF AVIAN BIOLOGY LA English DT Article ID DNA MARKERS; LINKAGE MAP; GENOME C1 Los Alamos Natl Lab, Biosci Div, Genom Grp, Los Alamos, NM 87545 USA. USGS, Patuxent Wildlife Res Ctr, Laurel, MD 20708 USA. RP Longmire, JL (reprint author), Los Alamos Natl Lab, Biosci Div, Genom Grp, POB 1663, Los Alamos, NM 87545 USA. EM longmire@telomere.lanl.gov NR 18 TC 5 Z9 5 U1 0 U2 3 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0908-8857 EI 1600-048X J9 J AVIAN BIOL JI J. Avian Biol. PD MAR PY 2001 VL 32 IS 1 BP 76 EP 78 DI 10.1034/j.1600-048X.2001.320111.x PG 3 WC Ornithology SC Zoology GA 420RW UT WOS:000168018800011 ER PT J AU Iwahara, J Wojciak, JM Clubb, RT AF Iwahara, J Wojciak, JM Clubb, RT TI Improved NMR spectra of a protein-DNA complex through rational mutagenesis and the application of a sensitivity optimized isotope-filtered NOESY experiment SO JOURNAL OF BIOMOLECULAR NMR LA English DT Article DE chemical exchange broadening; isotope-filtered experiment; mutation; protein complex ID 2D H-1-NMR SPECTRA; RECOGNITION SITES; HALF-FILTERS; DEAD RINGER; BINDING; CYCLOPHILIN; INVERSION; DOMAIN; FAMILY; PULSES AB The NMR spectra of the complex between the DNA-binding domain of the Dead ringer protein (DRI-DBD, Gly262-Gly398) and its DNA binding site (DRI-DBD:DNA, 26 kDa) have been optimized by biochemical and spectroscopic means. First, we demonstrate the utility of a modified 2D [F1,F2] C-13-filtered NOESY experiment that employs a (1)J(HC) versus chemical shift optimized adiabatic C-13 inversion pulse [Zwahlen, C. et al. (1997) J. Am. Chem. Soc., 119, 6711-6721]. The new sequence is shown to be more sensitive than previously published pulse schemes (up to 40% in favorable cases) and its utility is demonstrated using two protein-DNA complexes. Second, we demonstrate that the targeted replacement of an interfacial aromatic residue in the DRI-DBD:DNA complex substantially reduces line broadening within its NMR spectra. The spectral changes are dramatic, salvaging a protein-DNA complex that was originally ill suited for structural analysis by NMR. This biochemical approach is not a general method, but may prove useful in the spectral optimization of other protein complexes that suffer from interfacial line broadening caused by dynamic changes in proximal aromatic rings. C1 Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, US DOE, Lab Struct Biol & Genet, Los Angeles, CA 90095 USA. RP Clubb, RT (reprint author), Univ Calif Los Angeles, Dept Chem & Biochem, 405 Hilgard Ave, Los Angeles, CA 90095 USA. NR 23 TC 45 Z9 45 U1 1 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0925-2738 J9 J BIOMOL NMR JI J. Biomol. NMR PD MAR PY 2001 VL 19 IS 3 BP 231 EP 241 DI 10.1023/A:1011296112710 PG 11 WC Biochemistry & Molecular Biology; Spectroscopy SC Biochemistry & Molecular Biology; Spectroscopy GA 414ZJ UT WOS:000167695800003 PM 11330810 ER PT J AU Logan, J Fowler, JS Volkow, ND Ding, YS Wang, GJ Alexoff, DL AF Logan, J Fowler, JS Volkow, ND Ding, YS Wang, GJ Alexoff, DL TI A strategy for removing the bias in the graphical analysis method SO JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM LA English DT Article DE positron emission tomography; kinetic modeling; graphical analysis; distribution volume ID POSITRON EMISSION TOMOGRAPHY; RECEPTOR-BINDING; C-11 RACLOPRIDE; HUMAN BRAIN; PET DATA; LIGAND; REPRODUCIBILITY; TRACERS; MODEL AB The graphical analysis method, which transforms multiple time measurements of plasma and tissue uptake data into a linear plot, is a useful tool for rapidly obtaining information about the binding of radioligands used in PET studies. The strength of the method is that it does not require a particular model structure. However, a bias is introduced in the case of noisy data resulting in the underestimation of the distribution volume (DV), the slope obtained from the graphical method. To remove the bias, a modification of the method developed by Feng et al. (1993), the generalized linear least squares (GLLS) method, which provides unbiased estimates for compartment models was used. The one compartment GLLS method has a relatively simple form, which was used to estimate the DV directly and as a smoothing technique for more general classes of model structures. In the latter case, the GLLS method was applied to the data in two parts, that is, one set of parameters was determined for times 0 to T-1 and a second set from T-1 to the end time. The curve generated from these two sets of parameters then was used as input to the graphical method. This has been tested using simulations of data similar to that of the PET ligand [C-11]-d-threo-methylphenidate (MP, DV = 35 mL/mL) and C-11 raclopride (RAC, DV = 1.92 mL/mL) and compared with two examples from image data with the same tracers. The noise model was based on counting statistics through the half-life of the isotope and the scanning time. Five hundred data sets at each noise level were analyzed. Results (DV) for the graphical analysis (DV,), the nonlinear least squares (NLS) method (DV,,,), the one-tissue compartment GLLS method (DV,), and the two part GLLS followed by graphical analysis (DV,,) were compared. DV,, was found to increase somewhat with increasing noise and in some data sets at high noise levels no estimate could be obtained. However, at intermediate levels it provided a good estimation of the true DV. This method was extended to use a reference tissue in place of the input function to generate the distribution volume ratio (DVR) to the reference region. A linearized form of the simplified reference tissue method of Lammertsma and Hume (1996) was used. The DVR generated directly from the model (DVRFL) was compared with DVRFG (determined from a "smoothed" uptake curve as for DVFG) using the graphical method. 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 22 TC 105 Z9 105 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0271-678X J9 J CEREBR BLOOD F MET JI J. Cereb. Blood Flow Metab. PD MAR PY 2001 VL 21 IS 3 BP 307 EP 320 PG 14 WC Endocrinology & Metabolism; Hematology; Neurosciences SC Endocrinology & Metabolism; Hematology; Neurosciences & Neurology GA 408VJ UT WOS:000167347900014 PM 11295885 ER PT J AU Benezeth, P Palmer, DA Wesolowski, DJ AF Benezeth, P Palmer, DA Wesolowski, DJ TI Potentiometric study of the dissociation quotients of aqueous dimethylammonium ion as a function of temperature and ionic strength SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID SODIUM-CHLORIDE MEDIA; THERMODYNAMIC PROPERTIES; IONIZATION; ACID AB The acid dissociation equilibria involving aqueous dimethylammonium ion in the reaction (CH3)(2)NH2+ reversible arrow (CH3)(2)NH + H+ were measured potentiometrically with a hydrogen-electrode concentration cell from (0 to 290) degreesC in sodium-trifluoromethanesulfonate (NaTr) solutions at ionic strengths of (0.1, 0.3, and 1) molal. The molal dissociation quotients and selected literature data at infinite dilution were fitted by an empirical equation involving six adjustable parameters involving functions of temperature, solvent density, and ionic strength. This treatment yielded the following thermodynamic quantities at 25 degreesC and infinite dilution: log K-d = -10.77 +/- 0.02, DeltaH(d) = (50.8 +/- 0.7) kJ(.)mol(-1), DeltaS(d) = (-35.8 +/- 2.5) J(.)K(-1.)mol(-1), DeltaC(p,d) = (116 +/- 11) J(.)K(-1.)mol(-1), and DeltaV(d) = (-4.3 +/- 2.5) cm(3.)mol(-1). C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Benezeth, P (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008, Oak Ridge, TN 37831 USA. RI BENEZETH, Pascale/H-7969-2014 OI BENEZETH, Pascale/0000-0002-1841-2383 NR 20 TC 7 Z9 7 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD MAR-APR PY 2001 VL 46 IS 2 BP 202 EP 207 DI 10.1021/je0002134 PG 6 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 413WH UT WOS:000167634200006 ER PT J AU Phelan, JM Barnett, JL AF Phelan, JM Barnett, JL TI Solubility of 2,4-dinitrotoluene and 2,4,6-trinitrotoluene in water SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article AB Measurements of the aqueous solubility of 2,4-dinitrotoluene (DNT) and 2,4,6-trinitrotoluene (TNT) are reported. Previous data reported for DNT is sparse, and the values are inconsistent with those reported herein. Data for TNT compare very well with previously reported values, which provides confidence in the methods used. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Phelan, JM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 25 Z9 26 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD MAR-APR PY 2001 VL 46 IS 2 BP 375 EP 376 DI 10.1021/je000300w PG 2 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 413WH UT WOS:000167634200036 ER PT J AU Hollebeek, T Ho, TS Rabitz, H Harding, LB AF Hollebeek, T Ho, TS Rabitz, H Harding, LB TI Construction of reproducing kernel Hilbert space potential energy surfaces for the 1A '' and 1A ' states of the reaction N(D-2)+H-2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID EXCITED-STATES; ATOMS; H2O AB We present in detail the construction procedure of two high quality global potential energy surfaces that have recently been used in quasiclassical and quantum dynamics studies for the reaction N(D-2)+H-2--> NH+H. The procedure is based on the reproducing kernel Hilbert space method to interpolate high-level multireference configuration interaction ab initio calculations using augmented polarized triple zeta basis sets. A particular molecular coordinate system has been adopted to treat the nonadditive three body interaction as well as to guarantee the triangle inequalities of three molecular bond lengths and permutation symmetry of the two hydrogen atoms. A new radial reproducing kernel that remains finite at short distances while decaying to zero at large distances has been introduced, especially, for treating the molecule in the linear H-N-H configurations. Moreover, a robust procedure has been devised to handle the cusp in the two-body H-2 interaction associated with the 1 A" potential energy surface. The resulting surfaces are smooth, accurate, efficient to evaluate, exactly reproducing the input data upon which they are based and represent a significant improvement over previous surfaces for this reaction. (C) 2001 American Institute of Physics. C1 Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Hollebeek, T (reprint author), Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. NR 14 TC 13 Z9 13 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 2001 VL 114 IS 9 BP 3945 EP 3948 DI 10.1063/1.1346639 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 403LR UT WOS:000167044400011 ER PT J AU Rodriguez, JA Jirsak, T Perez, M Gonzalez, L Maiti, A AF Rodriguez, JA Jirsak, T Perez, M Gonzalez, L Maiti, A TI Studies on the behavior of mixed-metal oxides: Adsorption of CO and NO on MgO(100), NixMg1-xO(100), and CrxMg1-xO(100) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TOTAL-ENERGY CALCULATIONS; SOLID-SOLUTION CATALYSTS; BAND-GAP SIZE; CHEMICAL-REACTIVITY; THIN-FILMS; SURFACES; CHEMISORPTION; MO(100); DEPOSITION; DESORPTION AB Ultraviolet photoelectron spectroscopy (UPS), thermal desorption mass spectroscopy (TDS), and first-principles density functional (DF) generalized-gradient-corrected calculations were used to study the adsorption of CO and NO on MgO(100), Ni0.06Mg0.94O(100), and Cr0.07Mg0.93O(100) surfaces. UPS spectra and DF calculations show clear differences in the electronic properties of these oxides. After doping MgO with nickel, states with Ni 3d character appear similar to1.5 eV above the occupied {O 2p+Mg 3s} band. A similar phenomenon is found after adding Cr, but now the dopant levels are similar to3 eV above the {O 2p+Mg 3s} band. In CO- and NO-TDS experiments, the reactivity of the oxide surfaces increases in the sequence: MgO(100)< Ni0.06Mg0.94O(100)< Cr0.07Mg0.93O(100). Cr-bonded molecules exhibit adsorption energies as large as 15 (CO) and 20 kcal/mol (NO). For CO and NO on MgO(100), the mixing between the frontier orbitals of the adsorbate and the bands of the surface is poor, and the low adsorption energy is mainly due to weak MgO <----> CO or MgO <----> NO electrostatic interactions. On the other hand, the Cr 3d levels in Cr0.07Mg0.93O(100) are energetically well positioned for responding to the presence of adsorbates, leading to substantial binding of CO and NO. DF results for a series of TM0.06Mg0.94O(100) systems (TM=Zn, Ni, Fe, or Cr) show a correlation between their electronic and chemical properties: the less stable the occupied levels of a mixed-metal oxide, the higher its chemical reactivity. An important parameter to consider when designing a mixed-metal oxide catalyst is the final energy position of the occupied states provided by the second metal or dopant agent. (C) 2001 American Institute of Physics. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11953 USA. Cent Univ Venezuela, Fac Ciencias, Caracas 1020A, Venezuela. Mol Simulat Inc, San Diego, CA 92121 USA. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11953 USA. NR 67 TC 39 Z9 40 U1 2 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 2001 VL 114 IS 9 BP 4186 EP 4195 DI 10.1063/1.1345496 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 403LR UT WOS:000167044400037 ER PT J AU Barrena, E Ocal, C Salmeron, M AF Barrena, E Ocal, C Salmeron, M TI Structure and stability of tilted-chain phases of alkanethiols on Au(111) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; ATOMIC-BEAM DIFFRACTION; BUTANETHIOL MONOLAYERS; LENGTH DEPENDENCE; THIOLS; FILMS; DECANETHIOL; SURFACE; GOLD; ADSORPTION AB We present evidence for the existence of ordered tilted-chain phases of self-assembled monolayers of C18H37SH alkylthiols (C18) on Au(111). Tilted phases have been observed before under compressive stress in thiol and silanes monolayers. In the present experiments with C18, tilted phases have been observed to exist also in the absence of applied pressure. Atomic force microscopy (AFM) has been used to determine the thickness and lattice periodicity of the films. Two phases have been found to coexist: a hexagonal one with (root 3x root3)R30 degrees periodicity (tilt angle 35 degrees), which is characteristic of complete monolayers, and a less dense one with (2x root3)rect periodicity. This corresponds to a 50 degrees tilted phase, predicted by a chain-interlocking model. The new phase can be irreversibly transformed into the hexagonal phase by mechanical perturbation with the AFM tip. (C) 2001 American Institute of Physics. C1 CSIC, Inst Ciencia Mat Madrid, Dept Intercaras & Crecimiento, E-28049 Madrid, Spain. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Ocal, C (reprint author), CSIC, Inst Ciencia Mat Madrid, Dept Intercaras & Crecimiento, Plaza Murillo 2, E-28049 Madrid, Spain. RI Ocal, Carmen/G-8590-2013; Barrena, Esther/B-7683-2014 OI Ocal, Carmen/0000-0001-8790-8844; Barrena, Esther/0000-0001-9163-2959 NR 29 TC 49 Z9 49 U1 0 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 2001 VL 114 IS 9 BP 4210 EP 4214 DI 10.1063/1.1346676 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 403LR UT WOS:000167044400040 ER PT J AU McCoy, JD Teixeira, MA Curro, JG AF McCoy, JD Teixeira, MA Curro, JG TI Polymeric contributions to entropic surface forces SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DENSITY-FUNCTIONAL THEORY; NONUNIFORM POLYATOMIC SYSTEMS; MONTE-CARLO SIMULATION; BLOCK COPOLYMER THEORY; SELF-CONSISTENT-FIELD; HARD-SPHERE MIXTURES; INTEGRAL-EQUATION; SLITLIKE PORES; IMMISCIBLE POLYMERS; SOLVATION FORCES AB Density functional theory is applied to hard site chains between hard walls. The wall separation is varied and the normal pressures, surface excesses, and surface tensions are recorded. At low bulk density, a density depletion near the wall dominates the thermodynamic behavior. At high bulk density, the thermodynamic properties develop a damped oscillatory behavior with a period of approximately one site diameter and a range of roughly six site diameters. (C) 2001 American Institute of Physics. C1 New Mexico Inst Min & Technol, Dept Mat & Met Engn, Socorro, NM 87801 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP McCoy, JD (reprint author), New Mexico Inst Min & Technol, Dept Mat & Met Engn, Socorro, NM 87801 USA. RI McCoy, John/B-3846-2010 OI McCoy, John/0000-0001-5404-1404 NR 46 TC 26 Z9 26 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 2001 VL 114 IS 9 BP 4289 EP 4295 DI 10.1063/1.1344603 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 403LR UT WOS:000167044400050 ER PT J AU Kendrick, BK AF Kendrick, BK TI Geometric phase effects in the H+D-2 -> HD+D reaction (vol 112, pg 5679, 2000) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Correction C1 Univ Calif Los Alamos Natl Lab, Theoret Div, Los Alamos, NM 87545 USA. RP Kendrick, BK (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div, T-12,MS-B268, Los Alamos, NM 87545 USA. NR 1 TC 22 Z9 22 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 2001 VL 114 IS 9 BP 4335 EP 4342 DI 10.1063/1.1346648 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 403LR UT WOS:000167044400056 ER PT J AU Aslam, TD AF Aslam, TD TI A level-set algorithm for tracking discontinuities in hyperbolic conservation laws I. Scalar equations SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE shock tracking; ENO; WENO ID FINITE-DIFFERENCE METHODS; SHOCK-CAPTURING SCHEMES; ESSENTIALLY NONOSCILLATORY SCHEMES; HAMILTON-JACOBI EQUATIONS; WEIGHTED ENO SCHEMES; EFFICIENT IMPLEMENTATION; FRONT-TRACKING; NONLINEAR APPROXIMATIONS; PROPAGATION; FLOWS AB A level-set algorithm for tracking discontinuities in hyperbolic conservation laws is presented. The algorithm uses a simple finite difference approach, analogous to the method of lines scheme presented in C.-W. Shu and S. Osher (1988, J. Comput. Phys. 77, 439). The zero of a level-set function is used to specify the location of the discontinuity. Since a level-set function is used to describe the front location, no extra data structures are needed to keep track of the location of the discontinuity. Also, two solution states are used at all computational nodes, one corresponding to the ''real" state, and one corresponding to a "ghost node" state, analogous to the "Ghost Fluid Method" of R. P. Fedkiw et al. (1999, J. Comput. phys. 154, 459). High-order pointwise convergence is demonstrated for linear and nonlinear conservation laws, even at discontinuities and in multiple dimensions. The solutions are compared to standard high-order shock-capturing schemes. This paper focuses on scalar conservation laws. An example is given for shock tracking in the one-dimensional Euler equations. Level-set tracking for systems of conservation laws in multidimensions will be presented in future work. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Aslam, TD (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM aslam@lanl.gov NR 29 TC 21 Z9 27 U1 0 U2 5 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAR 1 PY 2001 VL 167 IS 2 BP 413 EP 438 DI 10.1006/jcph.2000.6686 PG 26 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 410WD UT WOS:000167463300006 ER PT J AU Ginn, TR Murphy, EM Chilakapati, A Seeboonruang, U AF Ginn, TR Murphy, EM Chilakapati, A Seeboonruang, U TI Stochastic-convective transport with nonlinear reaction and mixing: application to intermediate-scale experiments in aerobic biodegradation in saturated porous media SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article DE geochemistry; modeling; advection; chemical dispersion; biodegradation AB Aerobic biodegradation of benzoate by Pseudomonas cepacia sp. in a saturated heterogeneous porous medium was simulated using the stochastic-convective reaction (SCR) approach. A laboratory flow cell was randomly packed with low permeability silt-size inclusions in a high permeability sand matrix. In the SCR upscaling approach, the characteristics of the flow field are determined by the breakthrough of a conservative tracer. Spatial information on the actual location of the heterogeneities is not used. The mass balance equations governing the nonlinear and multicomponent reactive transport are recast in terms of reactive transports in each of a finite number of discrete streamtubes. The streamtube ensemble members represent transport via a steady constant average velocity per streamtube and a conventional Fickian dispersion term, and their contributions to the observed breakthroughs are determined by flux-averaging the streamtube solute concentrations. The resulting simulations were compared to those from a high-resolution deterministic simulation of the reactive transport, and to alternative ensemble representations involving (i) effective Fickian travel time distribution function, (ii) purely convective streamtube transport, and (iii) streamtube ensemble subset simulations. The results of the SCR simulation compare favorably to that of a sophisticated high-resolution deterministic approach. (C) 2001 Elsevier Science B.V. All lights reserved. C1 Univ Calif Davis, Dept Civil & Environm Engn, Davis, CA 95616 USA. Pacific NW Natl Lab, Richland, WA USA. RP Ginn, TR (reprint author), Univ Calif Davis, Dept Civil & Environm Engn, 1 Shields Ave, Davis, CA 95616 USA. NR 7 TC 17 Z9 17 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD MAR PY 2001 VL 48 IS 1-2 BP 121 EP 149 DI 10.1016/S0169-7722(00)00168-6 PG 29 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 402DK UT WOS:000166970600006 PM 11291477 ER PT J AU Muino, RD Rolles, D de Abajo, FJG Starrost, F Schattke, W Fadley, CS Van Hove, MA AF Muino, RD Rolles, D de Abajo, FJG Starrost, F Schattke, W Fadley, CS Van Hove, MA TI Multiple scattering theory for non-spherical potentials: application to photoelectron angular distributions from oriented diatomic molecules and the study of shape resonances SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE multiple scattering theory; photoelectrons; fixed-in-space molecules; electronic structure ID CO MOLECULES; PHOTOIONIZATION; ENERGY AB We use multiple scattering photoelectron diffraction theory to calculate the angular distribution of electrons photoemitted from core levels of fixed-in-space molecules. Non-spherical scattering potentials, needed for low photoelectron energies (E < 50 eV), are included in our formalism through non-diagonal scattering matrices; these fit directly into a new approach for multiple scattering theory originally based on spherical potentials. When the kinetic energy of the photoelectron is low its scattering cannot be adequately represented by spherically-symmetric potentials. In addition, we have considered the effect of the final-state hole, and found this to be important as well. As an example, we calculate the angular distribution of photoelectrons emitted from the K shells of C in oriented gas-phase CO molecules, as recently measured by several groups. Particularly important are the energies for which shape resonances appear in the continuum, with the angular distributions showing radical changes over such resonances. <(c)> 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Max Planck Gesell, Fritz Haber Inst, D-14195 Berlin, Germany. EHU, UPV, CSIC, Ctr Mixto, San Sebastian 20080, Spain. Univ Kiel, Inst Theoret Phys & Astrophys, D-24098 Kiel, Germany. Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Muino, RD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Rolles, Daniel/C-2384-2008; Van Hove, Michel/A-9862-2008; Diez Muino, Ricardo/C-9203-2009; Garcia de Abajo, Javier/A-6095-2009; CSIC-UPV/EHU, CFM/F-4867-2012; DONOSTIA INTERNATIONAL PHYSICS CTR., DIPC/C-3171-2014 OI Van Hove, Michel/0000-0002-8898-6921; Diez Muino, Ricardo/0000-0001-8593-0327; Garcia de Abajo, Javier/0000-0002-4970-4565; NR 21 TC 13 Z9 14 U1 0 U2 2 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 MAR PY 2001 VL 114 BP 99 EP 105 DI 10.1016/S0368-2048(00)00351-0 PG 7 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700016 ER PT J AU Rolles, D Muino, RD de Abajo, FJG Fadley, CS Van Hove, MA AF Rolles, D Muino, RD de Abajo, FJG Fadley, CS Van Hove, MA TI Elastic scattering of low-energy electrons by randomly oriented and aligned molecules - Influence of full non-spherical potentials SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS ID PHOTOELECTRON ANGULAR-DISTRIBUTIONS; CROSS-SECTIONS; DIATOMIC-MOLECULES; CO; NITROGEN; N-2; GAS AB Elastic scattering of low (10-50 eV) kinetic energy electrons from free diatomic molecules is studied using a single-center expansion of the full molecular potential. Dynamic exchange and polarization are included in a local form. The calculated elastic differential scattering cross-sections (DCS) for electron impact on CO and N-2 are in good agreement with available experimental data. The importance of using the full molecular potential instead of a two-center potential approach is pointed out. These corrections are small for energies above 50 eV; but they become increasingly important at lower energies. When discussing the angular distributions of elastically-scattered electrons from oriented molecules (like surface adsorbates), we show that these corrections are particularly significant. The results have implications for other electron scattering problems such as those encountered in low-energy photoelectron diffraction from both core and valence levels. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Max Planck Gesell, Fritz Haber Inst, D-14195 Berlin, Germany. EHU, UPV, CSIC, Ctr Mixto, San Sebastian 20080, Spain. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Muino, RD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Rolles, Daniel/C-2384-2008; Van Hove, Michel/A-9862-2008; Diez Muino, Ricardo/C-9203-2009; Garcia de Abajo, Javier/A-6095-2009; CSIC-UPV/EHU, CFM/F-4867-2012; DONOSTIA INTERNATIONAL PHYSICS CTR., DIPC/C-3171-2014 OI Van Hove, Michel/0000-0002-8898-6921; Diez Muino, Ricardo/0000-0001-8593-0327; Garcia de Abajo, Javier/0000-0002-4970-4565; NR 24 TC 5 Z9 5 U1 0 U2 2 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 MAR PY 2001 VL 114 BP 107 EP 113 DI 10.1016/S0368-2048(00)00350-9 PG 7 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700017 ER PT J AU Hamdan, NM Faiz, M AF Hamdan, NM Faiz, M TI An X-ray photoemission study of the effect of gamma-irradiation on fluorinated (Tl0.5Pb0.5)Sr1.6Ba0.4Ca2Cu3Oy high-T-C superconductor SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE T1-1223; XPS; gamma-irradiation; high-T-C superconductor ID CRITICAL-CURRENT DENSITY; HOLE CONCENTRATION; PHASE-FORMATION; TL-1223; YBA2CU3O7-DELTA; TEMPERATURE; ABSORPTION; ENERGY; SHIFT AB X-ray photoemission spectroscopy (XPS) has been used to investigate the effect of gamma -irradiation on F1s, Cu2p(3/2) and Sr3p(3/2) binding energies of fluorinated (Tl0.5Pb0.5)Sr1.6Ba0.4Ca2Cu3Oy superconductor. The F1s peak of this material started to disappear as gamma -dose was increased, indicating that gamma -irradiation creates vacancies in F and hence O sites las F partially replaces O). The Cu2p(3/2) satellite, that is typical of Cu2+, disappears and a low energy shoulder, that is a signature of Cu1+, develops as gamma -dose increases. Also the binding energy of Cu2p(3/2) was decreased with increasing gamma -irradiation, indicating a decrease in the average Cu valency. On the other hand, the binding energy of Sr3p(3/2) increases with increasing gamma -dose up to 30 Mrad. This also indicates a decrease in the hole concentration in the Cu-O planes of the fluorinated Tl-1223 because of removal of F/O from the Cu-O planes. As the irradiation dose is increased to 50 Mrad, the binding energy of Sr3p(3/2) decreases. This may be due to additional F/O removal from the Sr/Ba-O planes. (C) 2001 Elsevier Science B.V. reserved. All rights reserved. C1 King Fahd Univ Petr & Minerals, Dept Phys, Dhahran 31261, Saudi Arabia. RP Hamdan, NM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. NR 23 TC 2 Z9 2 U1 3 U2 4 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 MAR PY 2001 VL 114 BP 291 EP 294 DI 10.1016/S0368-2048(00)00283-8 PG 4 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700042 ER PT J AU Muramatsu, Y Watanabe, M Ueno, Y Shin, S Perera, RCC AF Muramatsu, Y Watanabe, M Ueno, Y Shin, S Perera, RCC TI Soft X-ray emission spectra in the OK region of oxygen incorporated in microporous carbon SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS ID ALPHA-CLUSTER CALCULATIONS; SURFACE; BENZENE AB Soft X-ray emission spectra in the O K region of oxygen incorporated in microporous carbon were measured using synchrotron radiation, in order to observe directly the oxygen on the graphitic surface in micropores and obtain information about its chemical bonding states. The O K X-ray emission spectra of the microporous carbon exhibited a main peak: at 526 eV with a low-energy tail, and the reference compounds also exhibited similar spectral features. A spectral feature analysis of the reference compounds using discrete variational X alpha molecular orbital calculations showed that the measured 526-eV peaks of the microporous carbon may be due to O2p orbitals and the low-energy tails be to the hybridized O2p/O2s orbitals. (C) 2001 Elsevier Science B.V. All rights reserved. C1 JAERI, Kansai Res Estab, Mikazuki, Hyogo 6795148, Japan. NTT, Lifestyle & Environm Technol Labs, Atsugi, Kanagawa 2430198, Japan. Univ Tokyo, Inst Solid State Phys, Kashiwa, Chiba 2778581, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RP Muramatsu, Y (reprint author), JAERI, Kansai Res Estab, 1-1-1 Koto, Mikazuki, Hyogo 6795148, Japan. RI Ueno, Yuko/H-5651-2012 NR 11 TC 1 Z9 1 U1 0 U2 0 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 MAR PY 2001 VL 114 BP 301 EP 305 DI 10.1016/S0368-2048(00)00417-5 PG 5 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700044 ER PT J AU Liu, P Shuh, DK AF Liu, P Shuh, DK TI Adsorption of O-2 on polycrystalline rhenium metal at room temperature studied by synchrotron X-ray photoemission spectroscopy SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE rhenium surfaces; oxygen adsorption; X-ray photoemission ID OXYGEN-ADSORPTION; XPS; UPS; DESORPTION; RE(0001); CO AB Clean rhenium (Re) surfaces were made by sputtering and annealing in UHV. The clean surfaces were then exposed to O-2 in the pressure range of 10(-8) (1 L) to 5 Torr (similar to1.5X10(7) L) at room temperature. The surface that was exposed at 5 Torr O-2 was also annealed at several temperatures. Core level spectra of the Re 4f and O ls were acquired at photon energies of 200 and 790 eV, respectively, from clean, O-2 exposed, and annealed surfaces. At least two components, approximately 1.4 eV apart, can be identified in the O Is spectra. One is attributed to atomic oxygen, and the other to molecular oxygen. At least two new features appear in the Re 4f spectra after the clean surfaces were exposed to O-2, and they may correspond to surface Re atoms surrounded by different numbers of oxygen. Annealing the O-2 exposed surfaces results in rearrangement of surface oxygen. Although equilibrium thermodynamic calculations predict that Re,O, is the most stable phase in the O-2 pressure and temperature range used in the exposure experiments, no appreciable Re oxide was observed, suggesting that the oxidation of Re metal is controlled by kinetics rather than thermodynamics. (C) 2001 Elsevier Science BN. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Glenn T Seaborg Ctr, Berkeley, CA 94720 USA. RP Shuh, DK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Glenn T Seaborg Ctr, Berkeley, CA 94720 USA. NR 17 TC 10 Z9 10 U1 4 U2 17 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 MAR PY 2001 VL 114 BP 319 EP 325 DI 10.1016/S0368-2048(00)00348-0 PG 7 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700047 ER PT J AU Mullins, DR AF Mullins, DR TI Reactions on model emission control catalysts studied by soft X-ray photoemission SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CA HO UNIV CALIF, CLARK KERR CAMPUS DE CeO2; NO; CO; isocyanate; rhodium; soft X-ray photoelectron spectroscopy ID OXIDE THIN-FILMS; SURFACES; CERIUM; CO; ADSORPTION; XPS; NO; SPECTROSCOPY; DISSOCIATION; RH(111) AB Model automotive exhaust catalysts have been studied by evaporating small amounts of Rh onto thin films of CeO2. Adjusting the O-2 pressure while the film is grown controls the initial oxidation state of the ceria. The ceria oxidation state may change as the system reacts with gaseous species. Ce4d and valence band photoemission are used to determine the Ce oxidation state. Rh3d spectra are used to study the growth of Rh on the CeOX and the response of the Rh particles to CO adsorption. The co-adsorption of NO and CO were studied on Rh/CeOX. These molecules interact to form OCN at 400 K. At higher temperatures the OCN decomposes and various carbon-nitrogen species without O are formed. These CXNY species are relatively stable. They decompose above 700 K to produce N-2 by N recombination and CO through a reaction of C with the CeOX. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. EM mullinsdr@ornl.gov NR 19 TC 10 Z9 10 U1 2 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 EI 1873-2526 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD MAR PY 2001 VL 114 BP 333 EP 337 DI 10.1016/S0368-2048(00)00269-3 PG 5 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700049 ER PT J AU Omori, S Nihei, Y Rotenberg, E Denlinger, JD Kevan, SD Tonner, BP Van Hove, MA Fadley, CS AF Omori, S Nihei, Y Rotenberg, E Denlinger, JD Kevan, SD Tonner, BP Van Hove, MA Fadley, CS TI Imaging of Cu(001) atoms by a new differential approach to photoelectron holography SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE photoelectron diffraction; photoelectron holography; differential holography; copper ID ELECTRON-EMISSION HOLOGRAPHY; MULTIPLE-SCATTERING; DIFFRACTION; PATTERNS; IMAGES AB We have applied a new differential method of photoelectron holography to both experimental and theoretical multiple-energy photoelectron diffraction data for Cu 3p bulk emission from Cu(001). Dominant forward-scattering effects contained in a normalized hologram chi (k) have been eliminated by taking the k-difference delta chi (k) along each direction k. Two data sets that are different in k-space sampling ranges and densities have been analyzed to compare atomic images reconstructed from chi and delta chi In both cases, the original scheme has yielded only very weak images of back-scattering atoms and spurious features in the forward-scattering directions. On the other hand, the differential scheme has been found to be successful in suppressing the forward-scattering effects to image not only side-scattering and back-scattering atoms in either case, but also forward-scattering atoms in one of the two cases. (C) 2001 Elsevier Science BN; All rights reserved. C1 Univ Tokyo, Inst Ind Sci, Tokyo 106, Japan. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Oregon, Dept Phys, Eugene, OR 97403 USA. Univ Cent Florida, Dept Phys, Orlando, FL 32816 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Omori, S (reprint author), Univ Tokyo, Inst Ind Sci, 7-22-1 Roppongi, Tokyo 106, Japan. RI Rotenberg, Eli/B-3700-2009; Van Hove, Michel/A-9862-2008; Kevan, Stephen/F-6415-2010 OI Rotenberg, Eli/0000-0002-3979-8844; Van Hove, Michel/0000-0002-8898-6921; Kevan, Stephen/0000-0002-4621-9142 NR 16 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD MAR PY 2001 VL 114 BP 455 EP 460 DI 10.1016/S0368-2048(00)00352-2 PG 6 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700069 ER PT J AU Armitage, NP Lu, DH Kim, C Damascelli, A Shen, KM Ronning, F Shen, ZX Onose, Y Taguchi, Y Tokura, Y AF Armitage, NP Lu, DH Kim, C Damascelli, A Shen, KM Ronning, F Shen, ZX Onose, Y Taguchi, Y Tokura, Y TI A photoemission investigation of the superconducting gap in an electron-doped cuprate superconductor SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE photoemission; neodymium; cuprate; superconductors; electron doped; gap ID THIN-FILMS; DOPING DEPENDENCE; FERMI-SURFACE; TEMPERATURE; ND1.85CE0.15CUO4-Y; ND2-XCEXCUO4-DELTA; SPECTROSCOPY AB We have performed angle resolved photoelectron spectroscopy (ARPES) on the electron-doped cuprate superconductor Nd1.85Ce0.15CuO4. Evidence is found for an anisotropic superconducting gap that is consistent with the existence of a d-wave superconducting order parameter in the n-type cuprate superconductors. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Univ Tokyo, Dept Appl Phys, Tokyo 1138656, Japan. RP Armitage, NP (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. RI Shen, Kyle/B-3693-2008; Taguchi, Yasujiro/A-3048-2010; Tokura, Yoshinori/C-7352-2009; damascelli, andrea/P-6329-2014 OI damascelli, andrea/0000-0001-9895-2226 NR 21 TC 1 Z9 1 U1 1 U2 2 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 MAR PY 2001 VL 114 BP 623 EP 627 DI 10.1016/S0368-2048(00)00258-9 PG 5 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700096 ER PT J AU Damascelli, A Shen, KM Lu, DH Armitage, NP Ronning, F Feng, DL Kim, C Shen, ZX Kimura, T Tokura, Y Mao, ZQ Maeno, Y AF Damascelli, A Shen, KM Lu, DH Armitage, NP Ronning, F Feng, DL Kim, C Shen, ZX Kimura, T Tokura, Y Mao, ZQ Maeno, Y TI Fermi surface of Sr2RuO4 from angle resolved photoemission SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE Sr2RuO4; photoemission; ARPES; fermi surface; electronic structure ID SUPERCONDUCTOR SR2RUO4 AB We investigated the low-energy electronic structure of Sr2RuO4 by angle-resolved photoemission spectroscopy (ARPES) focusing, in particular, on the controversial issues of the Fermi surface (FS) topology and of the extended van Hove singularity (evHs). A. detailed study of temperature and photon energy dependence demonstrates the surface-state nature of the electronic band responsible for the evils, and may suggest the presence of ferromagnetic correlations at the surface. In addition, we detected a replica of the primary FS that indicates a root2 x root2 surface reconstruction, as confirmed by LEED. In light of these findings, the FS determined by ARPES is consistent with LDA and de Haas-van Alphen (dHvA) results, and it provides additional information on the detailed shape of the alpha, beta and gamma sheets. Also, at this stage, because of the strong sensitivity of the cleaved surface, we could not find any robust signature of the crossover from 2D to 3D Fermi liquid behavior in our ARPES measurements for T < 130 K. <(c)> 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Univ Tokyo, Dept Appl Phys, Tokyo 1138656, Japan. JRCAT, Tsukuba, Ibaraki 3050046, Japan. Kyoto Univ, Dept Phys, Kyoto 6068502, Japan. JST, CREST, Kawaguchi, Saitama 3320012, Japan. RP Damascelli, A (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. RI Shen, Kyle/B-3693-2008; Tokura, Yoshinori/C-7352-2009; damascelli, andrea/P-6329-2014 OI damascelli, andrea/0000-0001-9895-2226 NR 11 TC 9 Z9 9 U1 1 U2 9 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 MAR PY 2001 VL 114 BP 641 EP 646 DI 10.1016/S0368-2048(00)00356-X PG 6 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700099 ER PT J AU Kang, JS Noh, TW Olson, CG Min, BI AF Kang, JS Noh, TW Olson, CG Min, BI TI Photoemission spectroscopy of half-metallic perovskite manganites Pr1-xSrxMnO3 SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE perovskite-manganites; photoemission; colossal magneto-resistance; electronic structures ID COLOSSAL-MAGNETORESISTANCE; MAGNETIC-FIELD; ABSORPTION; TRANSPORT AB The electronic structures of Pr1-xSrxMnO3 (PSMO; x=1/3, 1/2, 2/3) have been investigated by performing photoemission spectroscopy measurements and the LSDA band-structure calculations. The partial yield spectra and the constant-initial-state spectra near the Pr 4d absorption edge provide evidence that the Pr ions are nearly trivalent in PSMO. The Pr 4f and Mn 3d partial spectral weight (PSW) distributions of PSMO are found to be insensitive to x, reflecting the small overlap between Mn 3d and Pr 4f orbitals. The spectrum near the Fermi level exhibits evidence for the metal-insulator transitions with varying x, as well as a charge gap formation for x=1/2. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Catholic Univ Korea, Dept Phys, Puchon 422743, South Korea. Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Pohang Univ Sci & Technol, Dept Phys, Pohang 790784, South Korea. RP Kang, JS (reprint author), Catholic Univ Korea, Dept Phys, Puchon 422743, South Korea. RI Noh, Tae Won /K-9405-2013 NR 15 TC 8 Z9 8 U1 0 U2 2 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 MAR PY 2001 VL 114 BP 683 EP 688 DI 10.1016/S0368-2048(00)00293-0 PG 6 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700105 ER PT J AU Hasan, MZ Isaacs, E Shen, ZX Miller, LL AF Hasan, MZ Isaacs, E Shen, ZX Miller, LL TI Inelastic X-ray scattering as a novel tool to study electronic excitations in complex insulators SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE inelastic X-ray scattering; Mott insulators; correlated electron systems; electronic structure of cuprate superconductors; unoccupied bands; momentum-resolved spectroscopy ID TRANSITION; DEPENDENCE; SR2CUO2CL2; OXIDES AB We report particle-hole excitations in a cuprate insulator in the intermediate regimes of momentum-transfers (qa(o) similar to1.4 pi -3.1 pi, where q is the scattering vector and a, is the lattice constant) using high energy inelastic X-ray scattering. The excitation spectra show dispersive features near the Mott edge which shed light on the momentum structure of the upper Hubbard band in cuprates. We discuss the potential use of such a technique to study the momentum dependence of unoccupied bands in complex insulators. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. Iowa State Univ, Ames Labs, Ames, IA 50011 USA. RP Hasan, MZ (reprint author), Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. RI HASAN, M. Zahid/D-8237-2012 NR 19 TC 6 Z9 6 U1 0 U2 1 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 MAR PY 2001 VL 114 BP 705 EP 709 DI 10.1016/S0368-2048(00)00401-1 PG 5 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700109 ER PT J AU Ohldag, H Weber, NB Bethke, C Hillebrecht, FU AF Ohldag, H Weber, NB Bethke, C Hillebrecht, FU TI Surface antiferromagnetism of NiO studied by photoemission microscopy SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE antiferromagnetic surfaces; linear dichroism; photoemission microscopy; NiO ID RAY; DICHROISM; RADIATION; BEAMLINE AB Antiferromagnetic domains at surfaces of NiO single crystals were studied by polarization dependent soft X-ray absorption at the Ni2p absorption edges. Spatially resolved information is obtained by monitoring the absorption via the total yield of electrons in a photoemission electron microscope. On the (100) surface, stripe shaped domains are found with widths of the order of a few 10 mum, extending over 100s of mum. The polarization dependence shows a sign change of the contrast for every 90 degrees of rotation, as expected for the antiferromagnetic twin domains with the major portion of the antiferromagnetic axis within the plane of the surface. The domains are not affected by surface topography. This suggests that the formation of domains is governed by defects in the bulk, which lead to nucleation of domains at specific sites. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Dusseldorf, Inst Angew Phys, D-40225 Dusseldorf, Germany. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Max Planck Inst Mikrostrukturphys, D-06120 Halle, Germany. RP Hillebrecht, FU (reprint author), Univ Dusseldorf, Inst Angew Phys, Univ Str 1, D-40225 Dusseldorf, Germany. RI Ohldag, Hendrik/F-1009-2014 NR 17 TC 3 Z9 3 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD MAR PY 2001 VL 114 BP 765 EP 770 DI 10.1016/S0368-2048(00)00353-4 PG 6 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700119 ER PT J AU Morais, J Fecher, GH Denecke, R Liesegang, J Fadley, CS AF Morais, J Fecher, GH Denecke, R Liesegang, J Fadley, CS TI Dichroism in angular resolved XPS from gadolinium core-levels SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE gadolinium; photoemission; dichroism; magnetism ID MAGNETIC DICHROISM; PHOTOELECTRON DIFFRACTION; CIRCULAR-DICHROISM; PHOTOEMISSION; GD(0001); LIGHT; SPIN AB This work reports on measurements of the magnetic dichroism in angular resolved photoemission from the Gd 4l (l=s,p,d,f) core-levels of in-plane magnetised Gd films excited with linearly and circularly polarised, as well as unpolarised, Light. High resolution spectra were taken by means of the advanced photoelectron spectrometer-diffractometer end-station at the Advanced Light Source in Berkeley. The dichroism measurements were performed by physically rotating the sample azimuth to change the direction of the magnetisation axis relative to the incident Light. Strong asymmetries were observed, even when exciting the spectra with unpolarised light. This paper demonstrates how magnetic dichroism utilising unpolarised light easily gives information about the relative orientation of the magnetisation with respect to the plane of photon incidence. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Fed Rio Grande Sul, Inst Fis, Porto Alegre, RS, Brazil. Acad Sinica, Inst Phys, Taipei, Taiwan. Univ Erlangen Nurnberg, Lehrstuhl Phys Chem 2, Erlangen, Germany. La Trobe Univ, Dept Phys, Bundoora, Vic 3083, Australia. Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA USA. RP Fecher, GH (reprint author), Univ Mainz, Inst Phys, D-55099 Mainz, Germany. RI Fecher, Gerhard/H-2470-2011; Morais, Jonder/E-5022-2013; Register, CMSS/G-7191-2015 OI Morais, Jonder/0000-0002-4143-1208; NR 9 TC 6 Z9 6 U1 1 U2 7 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 MAR PY 2001 VL 114 BP 783 EP 788 DI 10.1016/S0368-2048(00)00405-9 PG 6 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700122 ER PT J AU Uda, M Yamashita, D Terashi, D Yamamoto, T Osawa, H Kanai, K Nakamatsu, H Perera, R AF Uda, M Yamashita, D Terashi, D Yamamoto, T Osawa, H Kanai, K Nakamatsu, H Perera, R TI XANES spectra of sesqui-oxides of Al, Cr and Fe SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE XANES; OK absorption; DV-X alpha MO calculation; alpha-Al2O3; Cr2O3; alpha-Fe2O3 AB Oxygen X-ray absorption near edge (XANES) spectra obtained from alpha -Al2O3, Cr2O3 and alpha -Fe2O3 were found to be clearly distinguishable. The energy distributions of the XANES spectra were reproduced here fairly well by the DV-X alpha molecular orbital calculation On the other hand, O K alpha spectra emitted from these oxides showed no significant difference. This indicates that the XANES is a very promising candidate to study the chemical environment of anions in typical ionic compounds. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Waseda Univ, Dept Mat Sci & Engn, Shinjuku Ku, Tokyo, Japan. Mat Sci & Technol Lab, Shinjuku Ku, Tokyo, Japan. Inst Phys & Chem Res, Wako, Saitama, Japan. Kyoto Univ, Inst Chem Res, Kyoto 611, Japan. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RP Uda, M (reprint author), Waseda Univ, Dept Mat Sci & Engn, Shinjuku Ku, Ohkubo 3-4-1, Tokyo, Japan. NR 5 TC 5 Z9 5 U1 0 U2 7 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 MAR PY 2001 VL 114 BP 819 EP 823 DI 10.1016/S0368-2048(00)00327-3 PG 5 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700128 ER PT J AU Wang, HX Patil, DS Gu, WW Jacquamet, L Friedrich, S Funk, T Cramer, SP AF Wang, HX Patil, DS Gu, WW Jacquamet, L Friedrich, S Funk, T Cramer, SP TI L-edge X-ray absorption spectroscopy of some Ni enzymes: probe of Ni electronic structure SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE Ni enzymes; Ni L-edges; hydrogenase; CO-dehydrogenase; superconducting tunneling junction detector ID DESULFOVIBRIO-GIGAS; CHROMATIUM-VINOSUM; NICKEL; HYDROGENASE; DETECTORS; COMPLEXES; SPECTRA; SITE; SPIN AB L-edge X-ray absorption spectroscopy has been used to study the electronic structure of Ni in the Ni-Fe hydrogenases and CO-dehydrogenases under a variety of conditions. The L-edge spectra are interpreted by comparison with the spectra of Ni model complexes and by ligand field multiplet simulations to examine the Ni oxidation and electronic spin states. The spectra for Ni in oxidized Desulfovibrio gigas and Pyrococcus furiosus enzymes are consistent with a covalent Ni-III species. All of the reduced hydrogenases in this study exhibit a high spin Ni-II spectrum, and no Ni-I has been observed. In contrast to hydrogenases, the native Clostridium thermoaceticum CO-dehydrogenase has a low spin Ni-II and exhibits a clearly different spectral multiplet. Spectroscopy of Ni enzymes using a 15-eV resolution STJ detector and using the new ALS beamline 4.0.2 with a 0.2 eV energy resolution show great promises for future biological L-edge spectroscopy. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Cramer, SP (reprint author), Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. NR 31 TC 27 Z9 27 U1 2 U2 12 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 MAR PY 2001 VL 114 BP 855 EP 863 DI 10.1016/S0368-2048(00)00370-4 PG 9 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700134 ER PT J AU Wang, H Patil, DS Ralston, CY Bryant, C Cramer, SP AF Wang, H Patil, DS Ralston, CY Bryant, C Cramer, SP TI L-edge X-ray magnetic circular dichroism of Ni enzymes: direct probe of Ni spin states SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE Ni enzymes; hydrogenase; magnetic circular dichroism; circular polarization; XMCD; sum rules ID NIFESE HYDROGENASE; TRANSITION-METALS; NICKEL; SPECTROSCOPY; SITE; ABSORPTION; MOMENT AB X-ray magnetic circular dichroism (XMCD) measures the inner shell absorption difference between left and right circularly polarized X-rays in the presence of magnetic field, and provides us a direct probe of the spin values localized in the specific metal sites. In this study, using Desulfovibrio desulfuricans and Desulfovibrio gigas hydrogenases as examples, we have measured the L-edge XMCD of Ni enzymes for the first time and analyzed them in comparison with a doped high spin Ni-II model complex. The reduced hydrogenases have a non-zero XMCD effect, which is consistent with a 'high spin' Ni-II site. The magneto-optical sum rules have also been used to derive the orbital and spin angular momentum. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Cramer, SP (reprint author), Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. NR 28 TC 10 Z9 10 U1 0 U2 5 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 MAR PY 2001 VL 114 BP 865 EP 871 DI 10.1016/S0368-2048(00)00375-3 PG 7 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700135 ER PT J AU Nelson, AJ van Buuren, T Miller, E Land, TA Bostedt, C Franco, N Whitman, PK Baisden, PA Terminello, LJ Callcott, TA AF Nelson, AJ van Buuren, T Miller, E Land, TA Bostedt, C Franco, N Whitman, PK Baisden, PA Terminello, LJ Callcott, TA TI X-ray absorption analysis of KDP optics SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE potassium dihydrogen phosphate (KDP); thermal effects; X-ray absorption ID CHEMICAL CHARACTERIZATION; SPECTROSCOPY AB Potassium dihydrogen phosphate (KDP) is a non-linear optical material used for laser frequency conversion and optical switches. Unfortunately, when KDP crystals are coated with a porous silica anti-reflection coating (Thomas, Appl. Opt. 1986;25(9):1481) and then exposed to ambient humidity, they develop dissolution pits (Wheeler et al., SPIE 1999;3902:451-459; Wheeler et al., Mater. Res. Sec. Conf., San Francisco, 2000). Previous investigations (Wheeler et al., SPIE 1999;3902:451-459) have shown that thermal annealing renders KDP optics less susceptible to pitting, suggesting that a modification of surface chemistry has occurred. X-ray absorption was used to characterize changes in the composition and structure of KDP optics as a function of process parameters. KDP native crystals were also analyzed to provide a standard basis for interpretation. Surface sensitive total electron yield and bulk sensitive fluorescence yield from the K2p, P2p (L-2,L-3-edge) and O1s (K-edge) absorption edges were measured at each process step. Results indicate that annealing at 160 degreesC dehydrates the surface of KDP resulting in a metaphosphate surface composition with K:P:O=1:1:3. (C) 2001 Elsevier Science BN. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Nelson, AJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, 700 E Ave,L-370, Livermore, CA 94550 USA. RI Whitman, Pamela/B-2336-2013; Franco, Nuno/N-8396-2013 OI Franco, Nuno/0000-0002-2393-8726 NR 10 TC 22 Z9 23 U1 1 U2 11 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 MAR PY 2001 VL 114 BP 873 EP 878 DI 10.1016/S0368-2048(00)00267-X PG 6 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700136 ER PT J AU Guo, JH Butorin, SM Wassdahl, N Warwick, T Nordgren, J AF Guo, JH Butorin, SM Wassdahl, N Warwick, T Nordgren, J TI The electronic structure of K6C60 studied by soft X-ray spectroscopy SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE C-60; K6C60; fulleride; soft X-ray absorption; soft X-ray emission ID KXC60; PHOTOEMISSION; PERFORMANCE; UNDULATOR; STATES; C-60 AB The electronic structure of C-60 and potassium doped C-60 has been studied by soft-X-ray absorption and emission spectroscopies. The C K alpha emission spectrum of doped C-60 shows a resolved filled lowest unoccupied molecular orbitals (LUMO) (t(1 alpha))-derived valence band. The intensity ratio of the highest occupied molecular orbitals (HOMO)-derived band to LUMO-derived band is 2, indicating that a K6C60 phase is forming the potassium doped C-60 film. Small variations with excitation energy in the spectral shape compared to solid C-60 suggest that resonant inelastic X-ray scattering becomes less prominent due to the formation of solid-state system upon potassium doping. (C) 2001 Elsevier Science BN; All rights reserved. C1 Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Guo, JH (reprint author), Univ Uppsala, Dept Phys, Box 530, S-75121 Uppsala, Sweden. NR 13 TC 3 Z9 3 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD MAR PY 2001 VL 114 BP 885 EP 888 DI 10.1016/S0368-2048(00)00407-2 PG 4 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700138 ER PT J AU Hayashi, H Watanabe, N Udagawa, Y Kao, CC AF Hayashi, H Watanabe, N Udagawa, Y Kao, CC TI Momentum dependence of pi-pi* excitations of benzene rings in condensed phases SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CA HO UNIV CALIF, CLARK KERR CAMPUS DE inelastic X-ray scattering; loss function; medium momentum transfer; molecular liquids; pi-pi* excitation; condensation effects ID X-RAY-SCATTERING; LIQUID WATER; SPECTROSCOPY; SPECTRUM AB Inelastic X-ray scattering (IXS) spectra for the pi-pi* excitation of benzene, toluene, polystyrene, and benzene-hexane solutions have been measured at medium momentum transfers (q), 0.35 less than or equal to q less than or equal to 1.5 Angstrom (-1). IXS profiles of these substances closely resemble each other. The pi-pi* peak of the pure substances shows a negative q-dispersion (similar to0.5 eV), while diluted benzene does not. For benzene, the loss function and the real (epsilon (1)) as well as the imaginary (epsilon (2)) parts of the dielectric function were deduced. It is shown that the pi-pi* excitation in liquids is well-localized and the q-dispersion can be interpreted by changes of the shielding factor epsilon (2)(1) + epsilon (2)(2). The properties of the loss function for molecular condensates are discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Tohoku Univ, Sci Measurements Res Inst, Sendai, Miyagi 9808577, Japan. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Hayashi, H (reprint author), Tohoku Univ, Sci Measurements Res Inst, Sendai, Miyagi 9808577, Japan. EM hayashi@rism.tohoku.ac.jp OI Hayashi, Hisashi/0000-0002-8504-4066 NR 19 TC 3 Z9 3 U1 0 U2 1 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 MAR PY 2001 VL 114 BP 933 EP 937 DI 10.1016/S0368-2048(00)00266-8 PG 5 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700145 ER PT J AU Shirley, EL Soininen, JA Zhang, GP Carlisle, JA Callcott, TA Ederer, DL Terminello, LJ Perera, RCC AF Shirley, EL Soininen, JA Zhang, GP Carlisle, JA Callcott, TA Ederer, DL Terminello, LJ Perera, RCC TI Modeling final-state interaction effects in inelastic X-ray scattering from solids: resonant and non-resonant SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE cBN; hBN; IXS; MgO; RIXS; X-ray scattering ID NEAR-EDGE STRUCTURE; HEXAGONAL BORON-NITRIDE; AB-INITIO CALCULATION; ELECTRON-HOLE INTERACTION; DYNAMIC STRUCTURE FACTOR; WIDE-GAP INSULATORS; ENERGY-LOSS SPECTRA; BAND-STRUCTURE; VALENCE-BAND; CORE-LEVEL AB We present resonant inelastic X-ray scattering calculations that realistically incorporate intermediate-state electron-core hole interactions and final-state electron-valence hole interactions. Intermediate-state interactions primarily affect the total fluorescence yield, whereas final-state interactions can change the relative strengths of spectral emission features. This is especially true in systems with strong valence-hole exciton effects. We also consider non-resonant excitation of core electrons. This work considers resonant scattering from B Is electrons in cubic boron nitride (cBN) and hexagonal boron nitride (hBN) and non-resonant scattering from Mg and O Is electrons in MgO, and compares theoretical results to experiment. (C) 2001 Elsevier Science B.V; All rights reserved. C1 NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Virginia Commonwealth Univ, Richmond, VA 23284 USA. Tulane Univ, Dept Phys, New Orleans, LA 70118 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Shirley, EL (reprint author), NIST, Opt Technol Div, 100 Bur Dr,Mail Stop 8441, Gaithersburg, MD 20899 USA. NR 48 TC 11 Z9 11 U1 1 U2 8 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 MAR PY 2001 VL 114 BP 939 EP 946 DI 10.1016/S0368-2048(00)00358-3 PG 8 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700146 ER PT J AU Faigel, G Tegze, M Marchesini, S Belakhovsky, M AF Faigel, G Tegze, M Marchesini, S Belakhovsky, M TI X-ray fluorescence holography SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE hard X-ray holography; synchrotron radiation ID ATOMIC-RESOLUTION AB In the last decade, hard X-ray holography using an inside reference point has been developed for the study of 3D atomic arrangements in solids. Two types of this method are used: "normal holography" in which the atoms serve as sources of X-radiation and "inverse holography" in which the atoms detect the interference field originating from the incident and scattered waves. Beside the first two demonstration experiments, there have not been many measurements of this type. The cause of this is that there are serious technical difficulties and evaluation problems, which have to be solved before there can be wider application. Lately, many of these problems have been overcome; so hard X-ray holography became a useful tool for structural studies. Recent developments in the field are discussed and the capabilities of the method are illustrated by examples. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Res Inst Solid State Phys & Opt, H-1525 Budapest, Hungary. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. CEA Grenoble, Dept Rech Fondamentale Mat Condensee, Serv Phys Mat & Microstruct, F-38054 Grenoble, France. RP Faigel, G (reprint author), Res Inst Solid State Phys & Opt, POB 49, H-1525 Budapest, Hungary. RI Marchesini, Stefano/A-6795-2009 NR 17 TC 3 Z9 4 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD MAR PY 2001 VL 114 BP 1063 EP 1068 DI 10.1016/S0368-2048(00)00392-3 PG 6 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700164 ER PT J AU Yang, SH Mun, BS Kay, AW Kim, SK Kortright, JB Underwood, JH Hussain, Z Fadley, CS AF Yang, SH Mun, BS Kay, AW Kim, SK Kortright, JB Underwood, JH Hussain, Z Fadley, CS TI Depth-resolved photoemission spectroscopy with soft X-ray standing waves SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE depth-resolved soft X-ray photoemission spectroscopy ID HIGH-RESOLUTION; MULTILAYER; SCATTERING; DIFFRACTION; REFLECTION; ASYMMETRY; REGION; FILMS AB Depth-resolved soft X-ray photoemission spectroscopy (SXPS) is performed in which depth sensitivity is provided by use of a periodic multilayer [B4C (22.5 Angstrom)/W (17.1 Angstrom)(40)] that shows sizeable standing wave effects of +/- similar to 50-60% for soft X-rays at hv approximate to 750 eV. The photoelectron intensities of each element in the sample, including impurity overlayers, are sharply altered when the incidence angle is tuned over the Bragg condition, in excellent agreement with theoretical simulations. The angular dependence of the photoelectron intensity also shows unique chemical-state resolved behavior depending on the location of a given species in the multilayer structure. Depth-resolved SXPS with soft X-ray standing wave excitation should thus be a very useful tool for studying surface and interface chemical, electronic and magnetic properties. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95016 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Fadley, CS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Mun, Bongjin /G-1701-2013; Kim, Sang-Koog/J-4638-2014 NR 25 TC 7 Z9 7 U1 0 U2 7 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 MAR PY 2001 VL 114 BP 1089 EP 1095 DI 10.1016/S0368-2048(00)00412-6 PG 7 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700168 ER PT J AU Strasser, T Solterbeck, C Schattke, W Bartos, I Cukr, M Jiricek, P Fadley, CS Van Hove, MA AF Strasser, T Solterbeck, C Schattke, W Bartos, I Cukr, M Jiricek, P Fadley, CS Van Hove, MA TI A theoretical investigation of photoemission spectra from (GaAs)(2)(AlAs)(2) superlattices SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE superlattices; III/V semiconductors; photoemission; one-step model ID GAAS(110) AB We calculated photoemission spectra within the one-step model for the (001) surface of the (AlAs)(2)(GaAs)(2) superlattice structure. The purpose is to discriminate between spectral features which are caused by the surface, and those which are characteristic properties of the superlattice. Direct transitions indicate the opening of band gaps at the Brillouin zone edge, which are characteristic for the modified periodicity of the superlattice. Furthermore, the layer resolved photocurrent shows that one can also identify excitations from AlAs which are hidden below the first two GaAs layers and from As atoms at the boundary between the different semiconductors. Furthermore, emissions from surface states and resonances are also recognized. (C) 2001 Elsevier Science BN. All rights reserved. C1 Univ Kiel, Inst Theoret Phys & Astrophys, D-24098 Kiel, Germany. Acad Sci Czech Republ, Inst Phys, Prague 16523 6, Czech Republic. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Schattke, W (reprint author), Univ Kiel, Inst Theoret Phys & Astrophys, Leibnizstr 15, D-24098 Kiel, Germany. RI Van Hove, Michel/A-9862-2008; Bartos, Igor/G-5780-2014; Jiricek, Petr/G-6428-2014 OI Van Hove, Michel/0000-0002-8898-6921; NR 7 TC 1 Z9 1 U1 0 U2 1 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 MAR PY 2001 VL 114 BP 1127 EP 1132 DI 10.1016/S0368-2048(00)00307-8 PG 6 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700173 ER PT J AU Suzer, S AF Suzer, S TI Deposition and stability of metal ions on oxidised silicon surfaces: electrochemical correlation SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE XPS; chemical states of Au; Hg; Tl; Pb; Bi; reduction potentials ID POROUS SILICON; REDUCTIVE DEPOSITION; GOLD; ANODIZATION; ABSORPTION; OXIDES AB XPS is used to determine the chemical state of Au, Hg, TI, Ph and Bi deposited from their corresponding aqueous solutions on oxidized silicon or gold surfaces. It is determined that Au and Hg, having positive electrochemical reduction potentials, deposit in their 0-valent state, but TI, Pb and Bi, having small positive or negative electrochemical reduction potentials, deposit in their corresponding ionic states, confirming our previous hypothesis about the electrochemical correlation. Electrochemical deposition of Au from aqueous solutions on to silicon electrodes yields 0-valent Au on both (+) and (-) polarised electrodes, with the only difference that more gold is deposited on the negatively biased one. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Bilkent Univ, Dept Chem, TR-06533 Bilkent, Turkey. RP Suzer, S (reprint author), Brookhaven Natl Lab, NSLS Bldg 725A-U8B, Upton, NY 11973 USA. NR 16 TC 6 Z9 6 U1 0 U2 0 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 MAR PY 2001 VL 114 BP 1151 EP 1154 DI 10.1016/S0368-2048(00)00302-9 PG 4 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700177 ER PT J AU Kay, AW de Abajo, FJG Yang, SH Arenholz, E Mun, BS Mannella, N Hussain, Z Van Hove, MA Fadley, CS AF Kay, AW de Abajo, FJG Yang, SH Arenholz, E Mun, BS Mannella, N Hussain, Z Van Hove, MA Fadley, CS TI Multi-atom resonant photoemission SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE angle resolved resonant photoemission; MARPE; X-ray emission; XPS ID PHOTOELECTRONS; SPECTROSCOPY; SCATTERING; IDENTITIES AB We review the present status of multi-atom resonant photoemission (MARPE), in which the photoelectron intensity from a core level on one atom is influenced by core-level absorption resonances on neighboring atoms of different atomic number. we find that some prior experimental data has been strongly influenced by detector non-linearity and that the effects seen in new corrected data are generally smaller and of different form. The corrected data are found to be well described by an extension of resonant photoemission theory to the interatomic case, provided that interactions beyond the usual second-order Kramers-Heisenberg treatment are included. This microscopic X-ray theory is also found to simplify under certain conditions so as to yield results equivalent to a classical X-ray optical approach, with the latter providing an alternative, although less detailed and general, physical picture of these effects. The present status of experimental results for such MARPE effects is discussed, together with the potential utility of these effects as near-neighbor probes, as well as their implications for X-ray emission and X-ray scattering experiments. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. EHU, UPV, CSIC, Ctr Mixto, San Sebastian, Spain. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Kay, AW (reprint author), Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RI Van Hove, Michel/A-9862-2008; Garcia de Abajo, Javier/A-6095-2009; CSIC-UPV/EHU, CFM/F-4867-2012; Mun, Bongjin /G-1701-2013; DONOSTIA INTERNATIONAL PHYSICS CTR., DIPC/C-3171-2014 OI Van Hove, Michel/0000-0002-8898-6921; Garcia de Abajo, Javier/0000-0002-4970-4565; NR 34 TC 11 Z9 11 U1 0 U2 8 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 MAR PY 2001 VL 114 BP 1179 EP 1189 DI 10.1016/S0368-2048(00)00429-1 PG 11 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700181 ER PT J AU Franco, N Klepeis, JE Bostedt, C Van Buuren, T Heske, C Pankratov, O Terminello, LJ AF Franco, N Klepeis, JE Bostedt, C Van Buuren, T Heske, C Pankratov, O Terminello, LJ TI Valence band study of the PtSi by synchrotron radiation photoelectron spectroscopy SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS DE valence band; synchrotron radiation photoelectron spectroscopy; local density approximation; Pt; Si ID ELECTRON; SILICON AB The electronic structure of PtSi was measured using synchrotron radiation-based valence band (VB) photoelectron spectroscopy (PES). We have compared our experimental results to local density approximation (LDA) calculations and have found that, contrary to previously suggested electronic structure models of localized Pt d-states amidst Si s and p electrons, the electronic structure of the silicide is more complex with evidence of two- and three-center covalent bonds between Pt and Si. The agreement between theory and experiment is discussed within the context of bond order hybridization between platinum and silicon. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Erlangen Nurnberg, D-91058 Erlangen, Germany. RP Franco, N (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI Pankratov, Oleg/C-5553-2013 NR 23 TC 9 Z9 9 U1 0 U2 4 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 MAR PY 2001 VL 114 BP 1191 EP 1196 DI 10.1016/S0368-2048(00)00431-X PG 6 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700182 ER PT J AU Shen, YL Li, W Fang, HE AF Shen, YL Li, W Fang, HE TI Phase structure and cyclic deformation in eutectic tin-lead alloy: A numerical analysis SO JOURNAL OF ELECTRONIC PACKAGING LA English DT Article ID 2-PHASE COMPOSITES AB This study is devoted to providing a mechanistic rationale of coarsening induced failure in solder alloys during thermomechanical fatigue. Micromechanical modeling of cyclic deformation of eutectic tin-lead alloy was undertaken using the finite element method. The models consist of regularly arranged tin-rich and lead-rich phases, simulating the lammellar array and colony structure in a typical eutectic system. A fine structure and a coarse structure, bearing the same phase fraction but different in the aspect ratio of each lead-rich layer and in the number of lead-rich layers in each colony, are utilized for representing the microstructure before and after coarsening, respectively. Both phases are treated as elastic-plastic solids with their respective properties. For simplicity the creep effect is ignored without compromising the main objective of this study. Cyclic lending under pure shear and unilaxial conditions is modeled It is found that both the fine and coarse structures exhibit essentially the same macroscopic stress-strain response. The coarse structure, however, shows a greater maximum effective plastic strain on a local scale throughout the deformation, The numerical result implies that, in a solder joint, a locally coarsened region may not be mechanically weaker than its surrounding, but it is subject to early damage initiation due to accumulated plasticity. Other implications regarding solder alloy failure and micromechanical modeling of two-phase materials are discussed. C1 Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Shen, YL (reprint author), Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. RI Shen, Yu-Lin/C-1942-2008 NR 15 TC 7 Z9 7 U1 0 U2 5 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1043-7398 J9 J ELECTRON PACKAGING JI J. Electron. Packag. PD MAR PY 2001 VL 123 IS 1 BP 74 EP 78 DI 10.1115/1.1324673 PG 5 WC Engineering, Electrical & Electronic; Engineering, Mechanical SC Engineering GA 412RK UT WOS:000167568000012 ER PT J AU Ruth, LA AF Ruth, LA TI Advanced coal-fired power plants SO JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 2nd International Conference on Advanced Energy Conversion Systems and Related Technologies (RAN98) CY DEC 01-03, 1998 CL NAGOYA UNIV, NAGOYA, JAPAN HO NAGOYA UNIV DE boilers; coal; combined-cycles; combustion; electric power plants; emissions; high performance power systems; indirectly fired cycles; low emission boiler systems; NOx control; SO2 control AB The (I.S, Department of Energy is partnering with industry To develop advanced coal-fired electric power plants that are substantially cleaner, more efficient, and less costly than current plants. Low-emission boiler systems (LEBS) and high-performance power systems (HIPPS) are based, respectively, on the direct firing of pulverized coal and the indirectly fired combined cycle. LEES uses a low-NOx slagging combustion system that has been shown in pilot-scale tests to emit less than 86 g/GJ (0.2 lb/10(6) Btu) of NOx. Additional NOx removal is provided by a moving bed copper oxide flue gas cleanup system, which also removes 97-99 percent of sulfur oxides. Stack levels of NOx can be reduced to below 9 g/GJ (0.02 lb/106 Btu). Construction of an 80 MWe LEES proof-of-concept plant is scheduled to begin in the spring of 1999. Engineering development of two different HIPPS configurations is continuing. Recent tests of a radians air heater, a key component of HIPPS, have indicated the soundness of the design for air temperatures to 1150 degreesC. LEES and HIPPS applications include both new power plants and repowering/upgrading existing plants. C1 US DOE, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. RP Ruth, LA (reprint author), US DOE, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. NR 6 TC 3 Z9 3 U1 0 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0195-0738 J9 J ENERG RESOUR-ASME JI J. Energy Resour. Technol.-Trans. ASME PD MAR PY 2001 VL 123 IS 1 BP 4 EP 9 DI 10.1115/1.1348270 PG 6 WC Energy & Fuels SC Energy & Fuels GA 425KB UT WOS:000168288800002 ER PT J AU Kaper, HG Nordborg, H AF Kaper, HG Nordborg, H TI The frozen-field approximation and the Ginzburg-Landau equations of superconductivity SO JOURNAL OF ENGINEERING MATHEMATICS LA English DT Article DE Ginzburg-Landau equations; superconductivity; frozen-field approximation; asymptotic analysis AB The Ginzburg-Landau (GL) equations of superconductivity provide a computational model for the study of magnetic Aux vortices in type-II superconductors. In this article it is shown through numerical examples and rigorous mathematical analysis that the GL model reduces to the frozen-field model when the charge of the Cooper pairs (the superconducting charge carriers) goes to zero while the applied field stays near the upper critical field. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. RP Kaper, HG (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Nordborg, Henrik/0000-0003-3432-3257 NR 18 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-0833 J9 J ENG MATH JI J. Eng. Math. PD MAR PY 2001 VL 39 IS 1-4 BP 221 EP 240 DI 10.1023/A:1004854616387 PG 20 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 422MH UT WOS:000168122100012 ER PT J AU Seaman, JC Arey, JS Bertsch, PM AF Seaman, JC Arey, JS Bertsch, PM TI Immobilization of nickel and other metals in contaminated sediments by hydroxyapatite addition SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID COMPETITIVE ADSORPTION; LEAD IMMOBILIZATION; MINERAL APATITE; SOILS; PHOSPHATE; SORPTION; URANIUM; OXALATE; PYROMORPHITE; SURFACE AB Batch experiments were conducted to evaluate the ability of hydroxyapatite (HA) to reduce the solubility of metals, including the primary contaminants of concern, Ni and U, from contaminated sediments located on the Department of Energy's Savannah River Site, near Aiken, SC. Hydroxyapatite was added to the sediments at application rates of 0, 5, 15.8, and 50 g kg(-1). After equilibrating in either 0.02 M KCl or 0.01 M CaCl2, the samples were centrifuged and the supernatants filtered prior to metal, dissolved organic C, and PO4 analyses. The treated soils were then air-dried and changes in solid-phase metal distribution were evaluated using sequential extractions and electron-based microanalysis techniques. Hydroxyapatite was effective at reducing the solubility of U and, to a lesser degree, Ni. Hydroxyapatite was also effective in reducing the solubility of Al, Ba, Cd, Co, Mn, and ph. Sequential extractions indicate that HA transfers such metals from more chemically labile forms, such as the water-soluble and exchangeable fractions, by altering solid-phase speciation in favor of secondary phosphate precipitates. Hydroxyapatite effectiveness was somewhat reduced in the presence of soluble organics that likely increased contaminant metal solubility through complexation. Arsenic and Cr solubility increased with HA addition, suggesting that the increase in pH and competition from PO4 reduced sorption of oxyanion contaminants. Energy dispersive x-ray (EDXA) analysis conducted in the transmission electron microscope (TEM) confirmed that HA amendment sequesters U, Ni, Pb, and possibly other contaminant metals in association with secondary Al-phosphates. C1 Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Aiken, SC 29802 USA. RP Seaman, JC (reprint author), Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Drawer E, Aiken, SC 29802 USA. OI Arey, J. Samuel/0000-0002-3189-1585 NR 44 TC 97 Z9 103 U1 5 U2 57 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD MAR-APR PY 2001 VL 30 IS 2 BP 460 EP 469 PG 10 WC Environmental Sciences SC Environmental Sciences & Ecology GA 445JY UT WOS:000169455400020 PM 11285906 ER PT J AU Gadelle, F Wan, JM Tokunaga, TK AF Gadelle, F Wan, JM Tokunaga, TK TI Removal of Uranium(VI) from contaminated sediments by surfactants SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID MICELLAR-ENHANCED ULTRAFILTRATION; COUNTERION BINDING; COMPLEXATION; ADSORPTION; URANYL; SOIL; EXTRACTION; HYDROLYSIS; TRANSPORT; EXCHANGE AB Uranium(VI) sorption onto a soil collected at the Melton Branch Watershed (Oak Ridge National Laboratory, TN) is strongly influenced by the pH of the soil solution and, to a lesser extent, by the presence of calcium, suggesting specific chemical interactions between U(VI) and the soil matrix. Batch experiments designed to evaluate factors controlling desorption indicate that two anionic surfactants, AOK and T77, at concentrations ranging from 60 to 200 mM, are most suitable for U(VI) removal from acidic soils such as the Oak Ridge sediment. These surfactants are very efficient solubilizing agents at low uranium concentrations: re. 100% U(M) removal fur [U(VI)](o).(sorbed) = 10(-6) mol kg(-1). At greater uranium concentrations (e.g., [U(VI)](o,sorbed) = ca. 10(-5) mol kg(-1)), the desorption efficiency of the surfactant solutions increases with an increase in surfactant concentration and reaches a plateau of 75 to 80% of the U(VI) initially sorbed. The must probable mechanisms responsible for U(VI) desorption include cation exchange in the electric double layer surrounding the micelles and, to a lesser extent, dissolution of the soil matrix. Limitations associated with the surfactant treatment include loss of surfactants onto the soil (sorption) and greater affinity between U(VI) and the soil matrix at large soil to liquid ratios. Parallel experiments with H2SO4 and carbonate-bicarbonate (CB) solutions indicate that these more conventional methods suffer from strong matrix dissolution with the acid and reduced desorption efficiency with CB due to the buffering capacity of the acidic soil. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Wan, JM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS 90-1116,1 Cyclotron Rd, Berkeley, CA 94720 USA. EM jmwan@lbl.gov RI Tokunaga, Tetsu/H-2790-2014; Wan, Jiamin/H-6656-2014 OI Tokunaga, Tetsu/0000-0003-0861-6128; NR 31 TC 27 Z9 30 U1 1 U2 8 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 EI 1537-2537 J9 J ENVIRON QUAL JI J. Environ. Qual. PD MAR-APR PY 2001 VL 30 IS 2 BP 470 EP 478 PG 9 WC Environmental Sciences SC Environmental Sciences & Ecology GA 445JY UT WOS:000169455400021 PM 11285907 ER PT J AU Adriano, DC Weber, JT AF Adriano, DC Weber, JT TI Influence of fly ash on soil physical properties and turfgrass establishment SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID COMBUSTION RESIDUES; ELEMENTS; ECOSYSTEMS AB A field study (1993-96) assessed the benefits of applying unusually high rates of coal by ash as a soil amendment to enhance water retention of soils without adversely affecting growth and marketability of the turf species, centipedegrass [Eremochloa ophiuroides (Munro) Hack.]. A Latin Square plot design was employed that included 0 (control, no ash applied), 280, 560, and 1120 Mg ha(-1) application rates of unweathered precipitator fly ash. The by ash was spread evenly over each plot area, rototilled, and allowed to weather under natural conditions for 8 mo before seeding. High levels of soluble salts, indicated by the electrical conductivity (EC) of soil extracts, in tandem with an apparent phytotoxic effect from boron (B), apparently inhibited initial plant establishment as shown by substantially lower germination counts in treated soil. However, plant height and rooting depth were not adversely affected, as were the dry matter (DM) yields throughout the study period. Ash treatment did not significantly influence water infiltration rate, bulk density, or temperature of the soil, but substantially improved water-holding capacity (WHC) and plant-available water (PAW). Enhanced water retention capacity improved the cohesion and handling property of harvested sod. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Adriano, DC (reprint author), Univ Georgia, Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. NR 41 TC 75 Z9 84 U1 0 U2 11 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD MAR-APR PY 2001 VL 30 IS 2 BP 596 EP 601 PG 6 WC Environmental Sciences SC Environmental Sciences & Ecology GA 445JY UT WOS:000169455400036 PM 11285922 ER PT J AU Porro, I AF Porro, I TI Hydrologic behavior of two engineered barriers following extreme wetting SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID CAPILLARY BARRIER; REGIONS; SITES AB Many engineered barriers are expected to function for hundreds of years or longer. Over the course of time, it is likely that some barriers will experience infiltration to the point of breakthrough. This study compares the recovery from breakthrough of two storage-evapotranspiration type engineered barriers. Replicates of test plots comprising thick soil and capillary-biobarrier covers were wetted to breakthrough in 1997. Test plots were kept cleared of vegetation to maximize hydrologic stress during recovery. Following cessation of drainage resulting from the wetting irrigations, water storage levels in all plots were at elevated levels compared with pre-irrigation levels. As a result, infiltration of melting snow during the subsequent spring overloaded the storage rapacity and produced drainage in all plots. Relatively rapid melting of accumulated snowfall produced the most significant infiltration events each year during the study. Capillary barriers yielded less total drainage than thick soil barriers. By limiting drainage, capillary barriers increased water storage in the upper portions of the test plots, which led to increased evaporation from the capillary barrier plots compared with thick soil plots. Increased evaporation in the capillary barrier plots allowed more water to infiltrate in the second season following the wetting tests without triggering drainage. All thick soil plots again yielded drainage in the second season. Within two years of intentionally induced breakthrough, evaporation alone (without transpiration) restored the capability of the capillary barrier covers to function as intended, although water storage in these covers remained at elevated levels. C1 Idaho Natl Engn & Environm Lab, Appl Geosci Dept, Idaho Falls, ID 83415 USA. RP Porro, I (reprint author), Idaho Natl Engn & Environm Lab, Appl Geosci Dept, POB 1625,2525 N Fremont Ave, Idaho Falls, ID 83415 USA. NR 33 TC 10 Z9 11 U1 1 U2 6 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD MAR-APR PY 2001 VL 30 IS 2 BP 655 EP 667 PG 13 WC Environmental Sciences SC Environmental Sciences & Ecology GA 445JY UT WOS:000169455400043 PM 11285929 ER PT J AU Thoma, SG Bonhomme, F Nyman, M Rodriguez, MA Nenoff, TM AF Thoma, SG Bonhomme, F Nyman, M Rodriguez, MA Nenoff, TM TI Synthesis and crystal structure of guanidinium tetrafluoro(trans-)dipyridinechromate(III), [CrF4(C5H5N)(2)](-)center dot CN3H6+ SO JOURNAL OF FLUORINE CHEMISTRY LA English DT Article DE coordination compound; chromium; fluoroamine; fluorochromate; synthesis; crystal structure; guanidinium; hydrogen bonded network AB A new chromium coordination compound, guanidinium tetrafluoro(trans-)dipyridinechromate(III), has been synthesized in one step under mild solvothermal conditions. [CrF4(C5H5N)(2)](-).[CN3H6](+) crystallizes in the monoclinic space group P2(1)/n, with a = 8.6054(8) Angstrom, b=13.3529(12) Angstrom, c=13.2952(12) Angstrom, and beta = 100.62(2)degrees. The structure consists of discrete guanidinium cations. CN3H6-, and tetrafluorodipyridinechromate anions, CrF4(C5H5N)(2)(-). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Catalysis & Chem Technol Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Mat Characterizat Dept, Albuquerque, NM 87185 USA. RP Nenoff, TM (reprint author), Sandia Natl Labs, Catalysis & Chem Technol Dept, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 3 Z9 3 U1 0 U2 0 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 MAR PY 2001 VL 108 IS 1 BP 73 EP 77 DI 10.1016/S0022-1139(00)00409-7 PG 5 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 416UB UT WOS:000167797600010 ER PT J AU Gosling, JT Riley, P Skoug, RM AF Gosling, JT Riley, P Skoug, RM TI Comment on "On the determination of electron polytrope indices within coronal mass ejections in the solar wind" by J. T. Gosling - Reply SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Editorial Material ID INTERPLANETARY MAGNETIC CLOUDS; 3-DIMENSIONAL PROPAGATION; ULYSSES OBSERVATIONS; EVOLUTION; EXPANSION; PRESSURE; STREAMER; INDEXES; DRIVEN; CMES C1 Univ Calif Los Alamos Natl Lab, Grp NIS 1, Los Alamos, NM 87545 USA. Sci Applicat Int Corp, San Diego, CA 92121 USA. RP Gosling, JT (reprint author), Univ Calif Los Alamos Natl Lab, Grp NIS 1, MS D466, Los Alamos, NM 87545 USA. NR 29 TC 3 Z9 3 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 2001 VL 106 IS A3 BP 3709 EP 3713 DI 10.1029/2000JA000407 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 407GN UT WOS:000167264000010 ER PT J AU Birn, J Drake, JF Shay, MA Rogers, BN Denton, RE Hesse, M Kuznetsova, M Ma, ZW Bhattacharjee, A Otto, A Pritchett, PL AF Birn, J Drake, JF Shay, MA Rogers, BN Denton, RE Hesse, M Kuznetsova, M Ma, ZW Bhattacharjee, A Otto, A Pritchett, PL TI Geospace Environmental Modeling (GEM) Magnetic Reconnection Challenge SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID X-LINE AB The Geospace Environmental Modeling (GEM) Reconnection Challenge project is presented and the important results, which are presented in a series of companion papers, are summarized. Magnetic reconnection is studied in a simple Harris sheet configuration with a specified set of initial conditions, including a finite amplitude, magnetic island perturbation to trigger the dynamics. The evolution of the system is explored with a broad variety of codes, ranging from fully electromagnetic particle in cell (PIC) codes to conventional resistive magnetohydrodynamic (MHD) codes, and the results are compared. The goal is to identify the essential physics which is required to model collisionless magnetic reconnection. All models that include the Hall effect in the generalized Ohm's law produce essentially indistinguishable rates of reconnection, corresponding to nearly Alfvenic inflow velocities. Thus the rate of reconnection is insensitive to the specific mechanism which breaks the frozen-in condition, whether resistivity, electron inertia, or electron thermal motion. The reconnection rate in the conventional resistive MHD model, in contrast, is dramatically smaller unless a large localized or current dependent resistivity is used. The Hall term brings the dynamics of whistler waves into the system. The quadratic dispersion property of whistlers (higher phase speed at smaller spatial scales) is the key to understanding these results. The implications of these results fbr trying to model the global dynamics of the magnetosphere are discussed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Electrodynam Branch, Greenbelt, MD 20771 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Univ Alaska, Inst Geophys, Fairbanks, AK 99775 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. RP Birn, J (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Hesse, Michael/D-2031-2012; Kuznetsova, Maria/F-6840-2012; Ma, Zhiwei/F-6986-2013; Shay, Michael/G-5476-2013 NR 16 TC 718 Z9 730 U1 7 U2 56 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 2001 VL 106 IS A3 BP 3715 EP 3719 DI 10.1029/1999JA900449 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 407GN UT WOS:000167264000011 ER PT J AU Hesse, M Birn, J Kuznetsova, M AF Hesse, M Birn, J Kuznetsova, M TI Collisionless magnetic reconnection: Electron processes and transport modeling SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID HYBRID SIMULATIONS; PARTICLE SIMULATION; MAGNETOTAIL RECONNECTION; EARTHS MAGNETOPAUSE; FIELD; DISSIPATION; DYNAMICS; PLASMAS; REGION; LAW AB Particle-in-cell simulations are used to investigate collisionless magnetic reconnection in thin current sheets, based on the configuration chosen for the Geospace Environment Modeling (GEM) magnetic reconnection challenge [Birn et al., this issue]. The emphasis is on the overall evolution, as well as details of the particle dynamics in the diffusion region. Here electron distributions show clear signatures of nongyrotropy, whereas ion distributions are simpler in structure. The investigations are extended to current sheets of different widths. Here we derive a scaling law for the evolution dependence on current sheet width. Finally, we perform a detailed comparison between a kinetic and Hall-magnetohydrodynamic model of the same system. The comparison shows that although electric fields appear to be quite similar, details of the evolution appear to be considerably different, indicative of the role of further anisotropies in the ion pressures. C1 NASA, Goddard Space Flight Ctr, Electrodynam Branch, Greenbelt, MD 20771 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Raytheo STX, Greenbelt, MD 20771 USA. RP Hesse, M (reprint author), NASA, Goddard Space Flight Ctr, Electrodynam Branch, Code 696, Greenbelt, MD 20771 USA. RI Hesse, Michael/D-2031-2012; Kuznetsova, Maria/F-6840-2012 NR 33 TC 129 Z9 133 U1 3 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 2001 VL 106 IS A3 BP 3721 EP 3735 DI 10.1029/1999JA001002 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 407GN UT WOS:000167264000012 ER PT J AU Birn, J Hesse, M AF Birn, J Hesse, M TI Geospace Environment Modeling (GEM) magnetic reconnection challenge: Resistive tearing, anisotropic pressure and Hall effects SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID TEMPERATURE ANISOTROPY; MAGNETOTAIL DYNAMICS; ENERGY RELEASE; SIMULATIONS; FLUID AB The nonlinear evolution of resistive tearing is studied ire various regimes, including one-fluid isotropic MHD, anisotropic (gyrotropic) MI-ID with terms approximating the effects of anisotropy driven instabilities, and Hall-MI-ID. Both uniform resistivity and spatially localized resistivity are investigated. The initial state is a plane one-dimensional current sheet with an initial perturbation representing a periodic structure with magnetic islands and x type neutral points, chosen for the "GEM magnetic reconnection challenge" [Birn et nl., this issue]. In the absence of dissipation, within ideal MHD, the initially imposed x type configuration collapses into a thin current sheet of finite length, while the magnetic islands contract, conserving their magnetic flux. The current density in the thin sheet becomes significantly enhanced, so that microscopic dissipation mechanisms can be expected to be ignited, even if they were absent in the initial state. Finite resistivity enables reconnection, and the growth of magnetic islands as in particle simulations. A comparison of reconnection rates shows that for the chosen initial current sheet thickness, a localized resistivity, corresponding to a Lundquist number (magnetic Reynolds number) of order unity, is necessary to approximate the growth and the reconnection electric field in the particle simulations. Pressure anisotropy, governed by double adiabatic conservation laws (modified by Ohmic heating), lends to reduced growth rates. This reduction is drastic for uniform resistivity. Isotropizing terms, modeling the effects of anisotropy driven microinstabilities again destabilize. Hall-MHD simulations can reproduce the fast growth of the particle simulations. The various models show both similarities and dissimilarities in their spatial structure. For similar amounts of reconnected flux, the variation of the normal magnetic field and of the (ion) how speed along the current sheet are similar, but electric field and current density show significant differences. C1 NASA, Goddard Space Flight Ctr, Electrodynam Branch, Greenbelt, MD 20771 USA. Univ Calif Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. RP Birn, J (reprint author), NASA, Goddard Space Flight Ctr, Electrodynam Branch, Code 696, Greenbelt, MD 20771 USA. RI Hesse, Michael/D-2031-2012 NR 17 TC 85 Z9 87 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 2001 VL 106 IS A3 BP 3737 EP 3750 DI 10.1029/1999JA001001 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 407GN UT WOS:000167264000013 ER PT J AU Kuznetsova, MM Hesse, M Winske, D AF Kuznetsova, MM Hesse, M Winske, D TI Collisionless reconnection supported by nongyrotropic pressure effects in hybrid and particle simulations SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETIC RECONNECTION; CURRENT SHEETS; TEARING MODE; X-LINE; FIELD; INSTABILITIES; DISSIPATION; TRANSPORT; REGION; PLASMA AB This paper presents the detailed comparative analysis of full particle and hybrid simulations of collisionless magnetic reconnection. The comprehensive hybrid simulation code employed in this study incorporates essential electron kinetics in terms of the evolution of the full electron pressure tensor in addition to the full ion kinetics and electron bulk flow inertia effects. As was demonstrated in our previous publications, the electron nongyrotropic pressure effects play the dominant role in supporting the reconnection electric field in the immediate vicinity of the neutral X point. The simulation parameters are chosen to match those of the Geospace Environmental Modeling (GEM) "Reconnection Challenge." It is that these comprehensive hybrid simulations perfectly reproduce the results of full particle simulations in many details. Specifically, the time evolutions of the reconnected magnetic flux and the reconnection electric field,, as well as spatial distributions of current density and magnetic field at all stages of the reconnection process, are found to be nearly identical for both simulations. Comparisons of variations of characteristic quantities along the x and z axes centered around the dominating X points also revealed a remarkable agreement. Noticeable differences are found only in electron temperature profiles, i.e., in the diagonal electron pressure tensor components. The deviation in the electron heating pattern in hybrid simulations from that observed in particle simulations, However, does not affect parameters essential for the reconnection process. In particular, the profiles of the off-diagonal components of the electron pressure tensor are found to be very similar for both runs and appear unaffected by heat flux effects. Both simulations also demonstrate that the E-y component of the electric field is nearly constant inside the diffusion region where ions are nonmagnetized. Wt: demonstrate that the simple analytical estimate for the reconnection electric field as a convection electric field at the edge of the diffusion region very well reproduces the reconnection electric field observed in the simulations. C1 Univ Calif Los Alamos Natl Lab, Div Appl Theoret Phys, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Electrodynam Branch, Greenbelt, MD 20771 USA. RP Kuznetsova, MM (reprint author), Raytheon ITSS Corp, Lanham, MD USA. RI Hesse, Michael/D-2031-2012; Kuznetsova, Maria/F-6840-2012 NR 32 TC 70 Z9 72 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 2001 VL 106 IS A3 BP 3799 EP 3810 DI 10.1029/1999JA001003 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 407GN UT WOS:000167264000018 ER PT J AU Scribner, KT Chesser, RK AF Scribner, KT Chesser, RK TI Group-structured genetic models in analyses of the population and behavioral ecology of poikilothermic vertebrates SO JOURNAL OF HEREDITY LA English DT Article; Proceedings Paper CT Symposium on DNA-Based Profiling of Mating Systems and Reproductive Behaviors in Poikilothermic Vertebrates CY JUN 17-20, 2000 CL YALE UNIV, NEW HAVEN, CONNECTICUT SP Amer Genet Assoc HO YALE UNIV ID BUFO-BUFO; EFFECTIVE SIZES; SOCKEYE-SALMON; COMMON TOAD; DIVERSITY; MINISATELLITE; DYNAMICS; WILDLIFE; TURTLES; SCRIPTA AB Estimates of gene correlations among individuals within and among populations are frequently derived from statistical analyses of genetic data (e.g., F statistics), These measures can be important tools in molecular ecology and conservation, and offer important insights into population breeding structure. Using recently derived theory developed for group-structured populations, we show that fixation indices, when combined with basic population ecological and demographic data can be used to investigate population mating systems and to predict dispersal rates, trajectories and asymptotic levels of fixation indices, and effective population size. Four case studies of poikilothermic vertebrates are used to demonstrate the broad utility of evolutionary and ecological inferences afforded by group-structured models. C1 Michigan State Univ, Dept Wildlife & Fisheries, E Lansing, MI 48824 USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC USA. Univ Georgia, Dept Genet, Aiken, SC USA. RP Scribner, KT (reprint author), Michigan State Univ, Dept Wildlife & Fisheries, 13 Nat Resources Bldg, E Lansing, MI 48824 USA. NR 46 TC 7 Z9 8 U1 0 U2 3 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 MAR-APR PY 2001 VL 92 IS 2 BP 180 EP 189 DI 10.1093/jhered/92.2.180 PG 10 WC Evolutionary Biology; Genetics & Heredity SC Evolutionary Biology; Genetics & Heredity GA 437RE UT WOS:000169006700012 PM 11396577 ER PT J AU Winne, CT Ryan, TJ Leiden, Y Dorcas, ME AF Winne, CT Ryan, TJ Leiden, Y Dorcas, ME TI Evaporative water loss in two natricine snakes, Nerodia fasciata and Seminatrix pygaea SO JOURNAL OF HERPETOLOGY LA English DT Article ID AQUATIC SNAKE; PERMEABILITY; DROUGHT C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Winne, CT (reprint author), Univ Georgia, Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. NR 32 TC 18 Z9 18 U1 0 U2 6 PU SOC STUDY AMPHIBIANS REPTILES PI ST LOUIS PA C/O ROBERT D ALDRIDGE, ST LOUIS UNIV, DEPT BIOLOGY, 3507 LACLEDE, ST LOUIS, MO 63103 USA SN 0022-1511 J9 J HERPETOL JI J. Herpetol. PD MAR PY 2001 VL 35 IS 1 BP 129 EP 133 DI 10.2307/1566035 PG 5 WC Zoology SC Zoology GA 413BE UT WOS:000167589400020 ER PT J AU de Gouvea, A Friedland, A Murayama, H AF de Gouvea, A Friedland, A Murayama, H TI Earth matter effect in Be-7 solar neutrino experiments SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE solar and atmospheric neutrinos; neutrino physics ID EXPONENTIALLY VARYING DENSITY; SUPER-KAMIOKANDE DETECTOR; ANALYTIC DESCRIPTION; VACUUM OSCILLATIONS; GALLIUM METAL; NIGHT; SUN; FLUX; REGENERATION AB We determine the sensitivity of the KamLAND and Borexino experiments to the neutrino regeneration effect in the Earth as a function of Deltam(2) and theta, using realistic numbers for the signal and background rates. We compare the results obtained with the chi (2) method with those obtained from the conventional day-night asymmetry analysis. We also investigate how well one should be able to measure the neutrino oscillation parameters if a large day-night asymmetry is observed, taking the LOW solution as an example. We present an enlarged parameter space, which contains mixing angles greater than pi /4 where the heavy mass eigenstate is predominantly nu (e), and determine the electron neutrino survival probability for this traditionally neglected scenario. We point out that this portion of the parameter space yields different physics results when dealing with the MSW solutions to the solar neutrino puzzle and should not be neglected. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP de Gouvea, A (reprint author), CERN, Div Theory, CH-1211 Geneva, Switzerland. EM andre.carvalho.de.gouvea@cern.ch; afriedland@lbl.gov; murayama@lbl.gov RI Murayama, Hitoshi/A-4286-2011 NR 47 TC 14 Z9 14 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD MAR PY 2001 IS 3 AR 009 PG 29 WC Physics, Particles & Fields SC Physics GA 428WM UT WOS:000168484700009 ER PT J AU Kim, H Park, D Tamaryan, S Muller-Kirsten, HJW AF Kim, H Park, D Tamaryan, S Muller-Kirsten, HJW TI Gross-Ooguri phase transition at zero and finite temperature: two circular Wilson loop case SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE duality in gauge field theories; AdS-CFT correspondance ID N GAUGE-THEORY; SPIN SYSTEMS; LIMIT; FIELD AB In the context of AdS/CFT correspondence the two Wilson loop correlator is examined at both zero and finite temperatures. On the basis of an entirely analytical approach we have found for Nambu-Goto strings the functional relation dS(c)((Reg))/dL = 2 pik between Euclidean action S-c and loop separation L with integration constant k, which corresponds to the analogous formula for point-particles. The physical implications of this relation are explored in particular for the Gross-Ooguri phase transition at finite temperature. C1 Kyungnam Univ, Dept Phys, Masan 631701, South Korea. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Kaiserslautern, Dept Phys, D-67653 Kaiserslautern, Germany. Yerevan Phys Inst, Theory Dept, Yerevan 375036 36, Armenia. RP Kim, H (reprint author), Kyungnam Univ, Dept Phys, Masan 631701, South Korea. EM hskim@hep.kyungnam.ac.kr; dkpark@quark.phy.bnl.gov; sayat@moon.yerphi.am; mueller1@physik.uni-kl.de NR 20 TC 49 Z9 49 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD MAR PY 2001 IS 3 AR 003 PG 13 WC Physics, Particles & Fields SC Physics GA 428WM UT WOS:000168484700003 ER PT J AU Freedman, VL Lopes, VL Hernandez, M AF Freedman, VL Lopes, VL Hernandez, M TI Parameter identifiability for three sediment entrainment equations SO JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING-ASCE LA English DT Article ID RAINFALL-RUNOFF MODELS AB A process-based erosion model is used to study parameterization problems of sediment entrainment equations in overland flow areas. One of the equations for entrainment by flow is developed based on a theory of excess stream power, while the other two relate to excess hydraulic shear. The investigation is conducted in two steps. The first step examines parameter optimization for simulated data sets where the parameter values are known. In the second step, parameter optimization for the most robust equation is examined using experimental data from rainfall simulator plots. Results demonstrate that although the model is capable of estimating total sediment yields with relatively small errors in parameter estimates, the converse is true when the optimization is performed for sediment concentrations. Although sediment yields calculated from simulated sediment concentrations match well with observed data, the parameter estimates generally underestimate sediment concentrations on the rising limb of the sediment graphs, and they overestimate them on the falling limb. This difficulty might be related to structural problems in the model, and unique solutions for parameter estimates cannot be obtained. C1 Pacific NW Natl Lab, Hydrol Grp, Richland, WA 99352 USA. Univ Arizona, Sch Renewable Nat Resources, Tucson, AZ 85721 USA. USDA ARS, SW Watershed Res Ctr, Tucson, AZ USA. RP Freedman, VL (reprint author), Pacific NW Natl Lab, Hydrol Grp, POB 999,MSIN K9-33, Richland, WA 99352 USA. NR 22 TC 1 Z9 1 U1 0 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-9437 J9 J IRRIG DRAIN E-ASCE JI J. Irrig. Drainage Eng-ASCE PD MAR-APR PY 2001 VL 127 IS 2 BP 92 EP 99 DI 10.1061/(ASCE)0733-9437(2001)127:2(92) PG 8 WC Agricultural Engineering; Engineering, Civil; Water Resources SC Agriculture; Engineering; Water Resources GA 415HG UT WOS:000167714900005 ER PT J AU Kaiser, LG Logan, JW Meersmann, T Pines, A AF Kaiser, LG Logan, JW Meersmann, T Pines, A TI Dynamic NMR microscopy of gas phase Poiseuille flow SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE Poiseuille flow; xenon NMR; gas phase NMR; Taylor dispersion; gas flow ID EDGE ENHANCEMENT; POROUS-MEDIA; DISPERSION; DIFFUSION; TRANSPORT AB Dynamic NMR microscopy has been used to study xenon gas undergoing Poiseuille flow in the regime where deterministic and stochastic motions are the same order of magnitude. For short observation time, the flow profile images are largely influenced by the longitudinal diffusion, manifested by large displacements in both positive and negative directions. For longer observation time, the effect of the mixing between the fast and slow flow components due to transverse diffusion becomes apparent. A spin-echo version of the dynamic NMR experiment yields images exhibiting strong distortions for longer observation time due to fast diffusion under the "natural" gradient from magnetic field inhomogeneity (compared to results obtained with a stimulated echo version). This effect is used as an edge-enhancement filter by employing a longer time duration of the imaging gradient in a stimulated echo experiment. (C) 2001 Academic Press. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Colorado State Univ, Dept Chem, Ft Collins, CO 80523 USA. RP Pines, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 16 TC 21 Z9 21 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD MAR PY 2001 VL 149 IS 1 BP 144 EP 148 DI 10.1006/jmre.2000.2283 PG 5 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 421TC UT WOS:000168078800021 ER PT J AU Gibson, JK AF Gibson, JK TI Reactions of actinide ions with ethylene oxide SO JOURNAL OF MASS SPECTROMETRY LA English DT Article DE actinides; ethylene oxide; actinide oxides; plutonium; americium; time-of-flight mass spectrometry; laser ablation ID GAS-PHASE REACTIVITY; LASER-ABLATION; NITROUS-OXIDE; METAL-IONS; CHEMISTRY; LANTHANIDE; ENERGIES; THERMOCHEMISTRY; HYDROCARBONS; OXIDATION AB Naked and oxo-ligated actinide (An) monopositive ions were reacted with ethylene oxide, cyclo-C2H4O (EtO). Along with An = U, Np, Pu and Am, ions of two lanthanide (Ln) elements, Ln = Tb and Tm, were studied for comparison. Metal and metal oxide ions, M+, MO+ and MO2+, were generated by laser ablation and immediately reacted with EtO. Unreacted and product ions were detected by time-of-flight mass spectrometry. It was apparent that the overall reaction cross-sections decreased in the order U+ greater than or equal to Np+ > Pu+ > Am+. A primary reaction channel for each studied metal was the formation of MO+ from M+, in accord with the expected exothermicity of oxygen abstraction from EtO. For U, Np and Pu, the dioxides were also major products, indicating OAn(+) -O dissociation energies of at least 350 kJ mol(-1) the energy required for O-atom abstraction from EtO. For Am, Tb and Tm, the dioxides were only very minor products, reflecting the stabilities of the trivalent states and resistance to oxidation to higher valence states; the structures/bonding in these MO2+ are intriguing given that the formal pentavalent bonding state is effectively unattainable. It was demonstrated that EtO, unlike more thermochemically favorable but kinetically restricted O-donors, is effective at achieving facile oxidation of actinide metal ions to the monoxide, and to the dioxide if the second O-abstraction reaction is exothermic. Several intriguing minor products were also identified, most of which incorporate metal-oxygen bonding and are attributed to the oxophilicity of the f-block elements; the contrast to the behavior of first-row d-block transition elements is striking in this regard. Particularly noteworthy was the formation of MH4+ (and MOH4+), evidently via abstraction of all four H atoms from a single C2H4O molecule; the structures/bonding in these novel 'hydride' species are indeterminate and warrant further attention. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Gibson, JK (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008,Bldg 5505,MS-6375, Oak Ridge, TN 37831 USA. NR 37 TC 15 Z9 15 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 MAR PY 2001 VL 36 IS 3 BP 284 EP 293 DI 10.1002/jms.129 PG 10 WC Biophysics; Chemistry, Organic; Spectroscopy SC Biophysics; Chemistry; Spectroscopy GA 418MJ UT WOS:000167895700004 PM 11312520 ER PT J AU Ralph, JM Schoeler, AC Krumpelt, M AF Ralph, JM Schoeler, AC Krumpelt, M TI Materials for lower temperature solid oxide fuel cells SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID INTERMEDIATE TEMPERATURE; CATHODE MATERIALS; CUBIC ZIRCONIA; ION CONDUCTORS; PART I; ELECTROLYTE; KINETICS; CONDUCTIVITY; PEROVSKITES; PERFORMANCE AB The solid oxide fuel cell (SOFC) continues to show great promise for the generation of electricity for an increasing range of applications. The present SOFC technology is based on an all-ceramic design, which eliminates the corrosion problems associated with fuel cells containing liquid electrolytes. To obtain good electrochemical performance with the currently used materials, this all-ceramic fuel cell operates at 1000 degreesC. Despite a significant amount of research and several successful demonstrations at the 100 kW level, commercialisation of the technology is not as rapid as anticipated. This is, in part, due to the high operating temperatures required, necessitating the use of expensive materials. As a result of these problems, there has been an effort over the past few years to lower the SOFC operating temperature. This paper will address the issues concerning the development of new materials that can operate at lower temperatures. Many of these issues have been or are being addressed in the research performed at Argonne National Laboratory, and some recent results will be discussed. (C) 2001 Kluwer Academic Publishers. C1 Argonne Natl Lab, Electrochem Technol Program, Argonne, IL 60439 USA. RP Ralph, JM (reprint author), Argonne Natl Lab, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. EM ralph@cmt.anl.gov NR 65 TC 226 Z9 235 U1 3 U2 79 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAR PY 2001 VL 36 IS 5 BP 1161 EP 1172 DI 10.1023/A:1004881825710 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 412VE UT WOS:000167574400014 ER PT J AU Georgiev, G Dai, PS Oyebode, E Cebe, P Capel, M AF Georgiev, G Dai, PS Oyebode, E Cebe, P Capel, M TI Real-time small angle X-ray scattering study of two-stage melt crystallization of PEEK SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID ETHER ETHER KETONE); POLY(ETHER IMIDE) BLENDS; SEMICRYSTALLINE MORPHOLOGY; POLY(PHENYLENE SULFIDE); THERMAL-EXPANSION; GLASS-TRANSITION; MOLECULAR-WEIGHT; RESOLVED SAXS; BEHAVIOR; POLY(ETHERETHERKETONE) AB We report a study of dual stage crystallization and subsequent melting of Poly(etherether ketone) (PEEK) and an 80/20 blend with Poly(etherimide) (PEI) using differential scanning calorimetry (DSC) and real-time small angle X-ray scattering (SAXS). The treatment scheme involves annealing/crystallization at T-1 followed by annealing/crystallization at T-2, where either T-1 < T-2 or T-1 > T-2. The holding time during isothermal melt treatment was varied. DSC studies show there exist two endotherms when T-1 < T-2, and three endotherms when T-1 > T-2, for both PEEK and PEEK/PEI blend. Dual populations of crystals form during the first stage regardless whether T-1 < T-2 or T-1 > T-2. In the high-to-low temperature sequence, holding at the second stage causes an additional third population of crystals to grow, creating a third endotherm. As the first stage holding time increases, space available for the growth of additional crystals decreases, and the amount of crystals formed during the second stage decreases. During melting, the average long period increases while the linear stack crystallinity decreases continuously. The average crystal thickness also first increases, as the least perfect, thinnest crystals melt. Eventually, the crystal thickness levels off and begins to decline with increasing temperature. Melting of the thickest, most perfect crystals occurs most probably from the surfaces accounting for the roll-off and decrease in crystal thickness during the final stages of melting. (C) 2001 Kluwer Academic Publishers. C1 Tufts Univ, Dept Phys & Astron, Medford, MA 02155 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Cebe, P (reprint author), Tufts Univ, Dept Phys & Astron, Medford, MA 02155 USA. NR 35 TC 4 Z9 4 U1 1 U2 11 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 MAR PY 2001 VL 36 IS 6 BP 1349 EP 1361 DI 10.1023/A:1017595201893 PG 13 WC Materials Science, Multidisciplinary SC Materials Science GA 414NP UT WOS:000167673000005 ER PT J AU Lessing, PA Erickson, AW Kunerth, DC AF Lessing, PA Erickson, AW Kunerth, DC TI Thermal cycling of siliconized-SiC at high temperatures SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID CERAMICS AB Thermal cycling (between 1340 degreesC and 1480 degreesC) experiments were conducted using two types of reaction-bonded (siliconized) silicon carbide. A commercial material (Crystar(TM)) and various silicon carbide pieces that had been joined together using electrophoretic deposition (EPD) followed by reaction bonding were evaluated. During the thermal cycling, residual "free" silicon metal rapidly vaporized from the Crystar(TM) and cracks developed within its large SiC grains. In contrast, the EPD/reaction-bonded silicon carbide joints did not lose an observable amount of their residual silicon nor develop cracks. The reduced loss was attributed to reduced silicon content with the silicon residing largely in closed pores of the EPD layer. Reduced vaporization of the silicon that resided in surface-connected pores was engineered by applying a thick SiC surface coating. The morphology of the resulting coating was microscopically evaluated and two sequential growth mechanisms were postulated. An implication of this research is that hermetic (gas-tight) joints could be formed using EPD-derived SiC as a filler material. (C) 2001 Kluwer Academic Publishers. C1 Idaho Natl Engn & Environm Lab, INEEL Res Ctr, Idaho Falls, ID 83415 USA. RP Lessing, PA (reprint author), Idaho Natl Engn & Environm Lab, INEEL Res Ctr, 2351 North Blvd, Idaho Falls, ID 83415 USA. NR 7 TC 2 Z9 4 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAR PY 2001 VL 36 IS 6 BP 1389 EP 1394 DI 10.1023/A:1017555507345 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 414NP UT WOS:000167673000010 ER PT J AU Peterson, PD Mortensen, KS Idar, DJ Asay, BW Funk, DJ AF Peterson, PD Mortensen, KS Idar, DJ Asay, BW Funk, DJ TI Strain field formation in plastic bonded explosives under compressional punch loading SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID IMPACT AB An inert simulant for one type of explosive formulation was subjected to low rate compressional punch deformation to determine the presence of potential strain initiation mechanisms. The presence of certain types of strain initiation mechanisms may lead to unintentional ignition in some explosive formulations. Laser induced fluorescence speckle photography was used to determine the magnitude and direction of the developing strain field during testing. Post-test SEM analyses was used to determine damage mechanisms occurring within the material. The magnitude and direction of the plastic flow lines show that a dead zone forms in the strain field immediately under the punch in agreement with Prandtl's slip-line solution of the punch problem. However, material flow patterns diverge from Prandtl's solution for other regions. Large shear strains also occur in the specimen, leading to the formation of slip bands in the hard phase constituent. (C) 2001 Kluwer Academic Publishers. C1 Univ S Carolina, Dept Mech Engn, Columbia, SC 29208 USA. Brigham Young Univ, Dept Mech Engn, Provo, UT 84602 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Peterson, PD (reprint author), Univ S Carolina, Dept Mech Engn, Columbia, SC 29208 USA. NR 24 TC 11 Z9 11 U1 3 U2 10 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAR PY 2001 VL 36 IS 6 BP 1395 EP 1400 DI 10.1023/A:1017572024183 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 414NP UT WOS:000167673000011 ER PT J AU Kim, BH Chung, TD Oh, CH Chun, K AF Kim, BH Chung, TD Oh, CH Chun, K TI A new organic modifier for anti-stiction SO JOURNAL OF MICROELECTROMECHANICAL SYSTEMS LA English DT Article DE dichlorodisilane (DDS); dialkyldichloromethylsilane (DDMS); self-assembled monolayers (SAM) ID SOLID-LIQUID INTERFACE; SILICA SURFACES; MONOLAYERS; TEMPERATURE; REDUCTION; ADHESION; RELEASE AB The chemical and mechanical characteristics of a new surface modifier, dialkyldichloromethylsilane (DDMS, CH3)(2)SiCl2), for stiction-free polysilicon surfaces are reported, The main strategy is to replace the conventional monoalkyl-trichlorosilane (MTS, RSiCl3) such as octadecyltrichlorosilane (ODTS) or 1H,1H,2H,2H-perfluorodecyltrichlorosilane (FDTS),vith dichlorodisilane (DDS, R2SiCl2) with two short chains, especially DDMS. DDMS, with shorter chains in aprotic media, rapidly deposits on the chemically oxidized polysilicon surface at room temperature and successfully prevents long cantilevers 3 mm in length from in-use as well as release stiction, DDMS-modified polysilicon surfaces exhibit satisfactory hydrophobicity, long term stability and thermal stability, which are comparable to those of FDTS, DDMS as an alternative to FDTS and ODTS provides a few valuable advantages; ease in handling and storage of the solution, low temperature-dependence and low cost, In addition to the new modifier molecule, the simplified process of direct release right after washing the modified surface with isooctane was proposed to cut the processing time. C1 Seoul Natl Univ, Sch Elect Engn, Seoul 151742, South Korea. Oak Ridge Natl Lab, Div Chem, Microinstrumentat Team, Oak Ridge, TN 37831 USA. RP Kim, BH (reprint author), Seoul Natl Univ, Sch Elect Engn, Seoul 151742, South Korea. RI Chung, Taek Dong/D-4007-2011 NR 22 TC 33 Z9 33 U1 0 U2 14 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1057-7157 J9 J MICROELECTROMECH S JI J. Microelectromech. Syst. PD MAR PY 2001 VL 10 IS 1 BP 33 EP 40 PG 8 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Instruments & Instrumentation; Physics, Applied SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation; Physics GA 411LR UT WOS:000167502000009 ER PT J AU Ashurst, WR Yau, C Carraro, C Maboudian, R Dugger, MT AF Ashurst, WR Yau, C Carraro, C Maboudian, R Dugger, MT TI Dichlorodimethylsilane as an anti-stiction monolayer for MEMS: A comparison to the octadecyltrichlosilane self-assembled monolayer SO JOURNAL OF MICROELECTROMECHANICAL SYSTEMS LA English DT Article DE MEMS; self-assembled monolayer; stiction; tribology ID ADHESION; SURFACES; BEAMS AB This paper presents a quantitative comparison of the dichlorodimethylsilane (DDMS) monolayer to the octadecyltrichlorosilane (OTS) self-assembled monolayer (SAM) with respect to the film properties and their effectiveness as anti-stiction coatings for micromechanical structures. Both coatings have been evaluated in several ways, including atomic force microscopy (AFM), contact angle analysis (CAA), work of adhesion by cantilever beam array (CBA) technique and coefficient of static friction using a sidewall testing device. While water and hexadecane contact angles are comparable, the DDMS coated microstructures exhibit higher adhesion than OTS coated ones. Furthermore, coefficient of static friction data indicate that the DDMS films are not as effective at lubrication as the OTS SAM's are, although both exhibit much improvement over chemical oxide. However, AFM data show that the samples which receive DDMS treatment accumulate fewer particles during processing than those which receive the OTS SAM treatment. The thermal stability of the DDMS film in air far exceeds the OTS SAM, as the DDMS remains very hydrophobic to temperatures upwards of 400 degreesC. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ashurst, WR (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. NR 21 TC 130 Z9 130 U1 6 U2 36 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1057-7157 J9 J MICROELECTROMECH S JI J. Microelectromech. Syst. PD MAR PY 2001 VL 10 IS 1 BP 41 EP 49 DI 10.1109/84.911090 PG 9 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Instruments & Instrumentation; Physics, Applied SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation; Physics GA 411LR UT WOS:000167502000010 ER PT J AU Meyer-Ilse, W Hamamoto, D Nair, A Lelievre, SA Denbeaux, G Johnson, L Pearson, AL Yager, D Legros, MA Larabell, CA AF Meyer-Ilse, W Hamamoto, D Nair, A Lelievre, SA Denbeaux, G Johnson, L Pearson, AL Yager, D Legros, MA Larabell, CA TI High resolution protein localization using soft X-ray microscopy SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article DE immunogold; protein localization; soft X-ray microscopy ID GREEN FLUORESCENT PROTEIN; RNA SPLICING FACTOR; TRANSMISSION; CELLS; TRANSCRIPTION; ORGANIZATION; TOMOGRAPHY; DYNAMICS; EMBRYOS; MATRIX AB Soft X-ray microscopes can be used to examine whole, hydrated cells up to 10 mum thick and produce images approaching 30 nm resolution Since cells are imaged in the X-ray transmissive 'water window', where organic material absorbs approximately an order of magnitude more strongly than water, chemical contrast enhancement agents are not required to view the distribution of cellular structures. Although living specimens cannot be examined, cells can be rapidly frozen at a precise moment in time and examined in a cryostage, revealing information that most closely approximates that in live cells, In this study, we used a transmission X-ray microscope at photon energies just below the oxygen edge (lambda = 2.4 nm) to examine rapidly frozen mouse 3T3 cells and obtained excellent cellular morphology at better than 50 nm lateral resolution. These specimens are extremely stable, enabling multiple exposures with virtually no detectable damage to cell structures, We also show that silver-enhanced, immunogold labelling can be used to localize both cytoplasmic and nuclear proteins in whole, hydrated mammary epithelial cells at better than 50 nm resolution. The future use of X-ray tomography, along with improved zone plate lenses, will enable collection of better resolution (approaching 30 nm), three-dimensional information on the distribution of proteins in cells. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Calif San Francisco, Dept Anat, San Francisco, CA 94143 USA. RP Larabell, CA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd,MS 6-2100, Berkeley, CA 94720 USA. RI Johnson, Lewis/G-1519-2013 FU NCI NIH HHS [CA-64786] NR 32 TC 112 Z9 116 U1 3 U2 22 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD MAR PY 2001 VL 201 BP 395 EP 403 DI 10.1046/j.1365-2818.2001.00845.x PN 3 PG 9 WC Microscopy SC Microscopy GA 414VJ UT WOS:000167686600007 PM 11240856 ER PT J AU De Solorzano, CO Malladi, R Lelievre, SA Lockett, SJ AF De Solorzano, CO Malladi, R Lelievre, SA Lockett, SJ TI Segmentation of nuclei and cells using membrane related protein markers SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article DE cell surface; confocal; geometrical flow; image segmentation; integrin; lamin; nuclear lamina; partial differential equation (PDE) ID THICK TISSUE-SECTIONS; SCANNING LASER MICROSCOPY; DNA IMAGE CYTOMETRY; EXTRACELLULAR-MATRIX; INVAGINATIONS; ALGORITHMS; INTEGRINS; PHENOTYPE; CURVATURE; GROWTH AB Segmenting individual cell nuclei from microscope images normally involves volume labelling of the nuclei with a DNA stain. However, this method often fails when the nuclei are tightly clustered in the tissue, because there is little evidence from the images on where the borders of the nuclei are. In this paper we present a method which solves this limitation and furthermore enables segmentation of whole cells. Instead of using volume stains, we used stains that specifically label the surface of nuclei or cells: lamins for the nuclear envelope and alpha-6 or beta-1 integrins for the cellular surface. The segmentation is performed by identifying unique seeds for each nucleus/cell and expanding the boundaries of the seeds until they reach the limits of the nucleus/cell, as delimited by the lamin or integrin staining, using gradient-curvature flow techniques. We tested the algorithm using computer-generated objects to evaluate its robustness against noise and applied it to cells in culture and to tissue specimens. In all the cases that we present the algorithm gave accurate results. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lockett, SJ (reprint author), SAIC Frederick, POB B, Frederick, MD 21702 USA. RI Ortiz de Solorzano, Carlos/G-3278-2010 OI Ortiz de Solorzano, Carlos/0000-0001-8720-0205 FU NCI NIH HHS [CA-64786, CA-67412] NR 35 TC 85 Z9 86 U1 1 U2 7 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD MAR PY 2001 VL 201 BP 404 EP 415 PN 3 PG 12 WC Microscopy SC Microscopy GA 414VJ UT WOS:000167686600008 PM 11240857 ER PT J AU Huang, R Espenson, JH AF Huang, R Espenson, JH TI Molecular oxygen reactions catalyzed by an oxorhenium(V) compound SO JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL LA English DT Article DE catalysis; rhenium; oxygen; phosphine ID ATOM-TRANSFER-REACTIONS; METHYLRHENIUM TRIOXIDE; HYDROGEN-PEROXIDE; OXIDATION; OXIDES; RHENIUM(V); DISULFIDES; SULFOXIDES; MECHANISMS; KINETICS AB The new binuclear oxothiolatorhenium(V) compound, Re2O2(mtp)(3), D-1, mtpH(2) = 2-(mercaptomethyl)thiophenol. was found to activate molecular oxygen. which has no precedent in oxorhenium catalysis. The kinetics and mechanism of the oxidation of triaryl phosphines and methyl phenyl phosphines by O-2 were investigated. The reaction pathway inferred from the kinetic data involves two Re(VII) intermediates, a peroxo and a mu -oxo species. The rate constants were determined for both steps in this reaction. The mu -oxo Re(VII) intermediate further reacts with a second phosphine forming more phosphine oxide as D-1 is recovered. This step is very rapid, and does not affect the kinetics. Other substrates, taken alone, such as sulfides and dienes, which coordinate to D-1 weakly, or do not coordinate, were not oxidized by molecular oxygen. However, in the presence of a small amount of phosphine to open up the sulfur bridge in D-1, then sulfides and dienes were also oxidized to sulfoxides and epoxides accordingly. The relative reactivities of the substrates fall in the order: phosphines > sulfides > dienes. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 18 TC 23 Z9 23 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1381-1169 J9 J MOL CATAL A-CHEM JI J. Mol. Catal. A-Chem. PD MAR 1 PY 2001 VL 168 IS 1-2 BP 39 EP 46 DI 10.1016/S1381-1169(00)00525-2 PG 8 WC Chemistry, Physical SC Chemistry GA 411YD UT WOS:000167526500006 ER PT J AU Li, LY Li, H Qian, MX Strachan, DM AF Li, LY Li, H Qian, MX Strachan, DM TI Gadolinium solubility in peraluminous borosilicate glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; EARTH ALUMINOSILICATE GLASSES; LANTHANUM BORATE GLASSES; LEVEL LIQUID WASTES; CEO2-AL2O3-SIO2 GLASSES; NMR; VITRIFICATION; IMMOBILIZATION; NA2O-B2O3-SIO2; DISPOSITION AB This paper discusses the results of a study with 18 peraluminous (Na/Al<1) borosilicate glasses to understand the effect of glass composition on Gd solubility. Above Gd solubility limit, phase separation occurs in some of the glasses; in the others, sodium gadolinium silicate crystallizes. For the samples in which phase separation occurs, Gd solubility is determined by the [AlO1.5]-[NaO0.5]-0.2[BO1.5] values in the melt. Increasing [AlO1.5]-[NaO0.5]-0.2[BO1.5] increases Gd solubility. For the samples in which sodium gadolinium silicate crystallizes, Gd solubility is determined by the concentration of Na. Increasing Na decreases Gd solubility. When Al concentration in the baseline glass is high, a minimum amount of Gd is needed to form a clear glass. Otherwise, mullite crystallizes. The minimum concentration of Gd is determined by the [AlO1.5]-[NaO0.5]-[BO1.5] value in the melt. The higher this value, the more Gd is needed to form a clear glass. In general, the solution behavior of Gd in peraluminous borosilicate melts is similar to that in peralkaline borosilicate melts. <(c)> 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Li, LY (reprint author), Pacific NW Natl Lab, POB 999 K8-93, Richland, WA 99352 USA. NR 45 TC 18 Z9 18 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAR PY 2001 VL 281 IS 1-3 BP 189 EP 197 DI 10.1016/S0022-3093(00)00441-5 PG 9 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 414AK UT WOS:000167643600022 ER PT J AU Bastasz, R Eckstein, W AF Bastasz, R Eckstein, W TI Plasma-surface interactions on liquids SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE sputtering; erosion; retention ID SPUTTERING YIELD; BINARY-ALLOYS; LITHIUM; TEMPERATURE; SEGREGATION; INTERFACES; DEPENDENCE; DIFFUSION; DESIGN AB Liquid plasma-facing surfaces have been suggested as an option for advanced fusion devices, particularly in regions where solid materials may not survive over long operating periods. Because liquid surfaces can be replenished, they offer the possibility of tolerating intense particle bombardment and of recovering from off-normal events. As a preliminary step in understanding the nature of plasma-surface interactions on liquids, we consider some of the surface processes occurring in liquids undergoing irradiation by energetic particles. These include (1) sputtering, (2) segregation of liquid component species and impurities, (3) evaporation, and (4) trapping and release of incident particles. Aspects of these processes are examined for a few candidate liquids of various types: pure metals (Li), metallic alloys (Sn-Li), and compound insulators (Li2BeF4). (C) 2001 Published by Elsevier Science B.V. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Max Planck Inst Plasmaphys, Garching, Germany. RP Bastasz, R (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. NR 34 TC 22 Z9 23 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 19 EP 24 DI 10.1016/S0022-3115(00)00557-2 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700004 ER PT J AU Anderl, RA Pawelko, RJ Schuetz, ST AF Anderl, RA Pawelko, RJ Schuetz, ST TI Deuterium retention in W, W1%La, C-coated W and W2C SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE divertor material; hydrogen; ion irradiation; tungsten; carbon ID TUNGSTEN; REEMISSION AB This paper reports the results of a systematic investigation into retention of deuterium implanted into various forms of W including: reduction-rolled, powder-metallurgy foil; discs of W1%La alloy; W and W2C prepared by chemical vapor deposition (CVD) and annealed C-coated W discs, Deuterium was implanted at energies of 0.5 keV/D with fluxes of similar to3 x 10(19) D/m(2) s and fluences of 3 x 10(23) D/m(2), for samples at temperatures from 23 degreesC to 400 degreesC. Retained deuterium quantities were measured using thermal desorption spectroscopy (TDS). Retention in annealed CVD-W and W1%La. for implantation temperatures less than 200 degreesC, is below that in annealed W foil, indicating that trapping may be affected by the different material defect structures. For implantation temperatures less than 300 degreesC, retention in CVD-W2C is somewhat higher than that in CVD-W, indicating trapping could be enhanced by trace carbon impurities, differences in W2C material structure and recoil carbon-induced material damage. Implantation into C-coated W resulted in orders of magnitude more retention than in uncoated material, because of trapping in the carbon coating. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Anderl, RA (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 16 TC 14 Z9 14 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 38 EP 41 DI 10.1016/S0022-3115(00)00622-X PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700007 ER PT J AU Ruhr, RA Roth, J Eckstein, W von Toussaint, U Luthin, J AF Ruhr, RA Roth, J Eckstein, W von Toussaint, U Luthin, J TI Implantation, erosion, and retention of tungsten in carbon SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Controlled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE implantation; erosion; retention; tungsten; carbon ID ION-BEAM EXPERIMENTS; ENERGY RESOLUTION; ENHANCEMENT; REGION AB The bombardment of C with 100 keV W at normal incidence is studied as a function of the incident W fluence experimentally and by computer simulation with the program TRIDYN. Calculated oscillations in the amount of retained W and in the target weight change are confirmed experimentally, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Max Planck Inst Plasma Phys, D-85748 Garching, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Max Planck Inst Plasma Phys, Boltzmannstr 2, D-85748 Garching, Germany. EM roth@ipp.mpg.de NR 16 TC 9 Z9 9 U1 0 U2 1 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 MAR PY 2001 VL 290 BP 162 EP 165 DI 10.1016/S0022-3115(00)00569-9 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700034 ER PT J AU Brooks, JN Rognlien, TD Ruzic, DN Allain, JP AF Brooks, JN Rognlien, TD Ruzic, DN Allain, JP TI Erosion/redeposition analysis of lithium-based liquid surface diverters SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE erosion; redeposition; lithium ID ELECTRON-IMPACT IONIZATION; RECOMMENDED DATA; ATOMS; IONS AB A sputtering erosion/redeposition analysis was performed for three candidate tokamak fusion reactor liquid divertor surfaces-lithium, tin-lithium (Sn80Li20), and flibe (LiF + BeF2 salt). The analysis uses coupled edge-plasma, impurity-transport, and sputtering codes (UEDGE/WBC/VFTRIM), and available sputtering data. A pure-lithium surface strongly absorbs impinging D-T ions-this results in a high temperature, low density, (similar to 200 eV, similar to1 x 10(19) m(-3)) low-recycle plasma edge regime. Lithium appears to perform well in this regime. Although overall sputtering is high, self-sputtering is finite. Most (similar to 95%) of the sputtered lithium is confined to the near-surface region and redeposited on the divertor with the remainder (similar to5%) also being redeposited after transport in the scrape-off layer. Lithium core plasma contamination is low (similar to 10(-4) Li/D-T). Tin-lithium and flibe would likely operate in a high-recycle regime (e.g., 30 eV, 3 x 10(20) m(-3)). Erosion/redeposition performance of these materials is also good, with finite self-sputtering and negligible core plasma contamination predicted, but with some concern about changing surface composition due to different constituent element redeposition distances. (C) 2001 Published by Elsevier Science B.V. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Illinois, Urbana, IL 61801 USA. RP Brooks, JN (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Allain, Jean Paul/0000-0003-1348-262X NR 13 TC 29 Z9 32 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 MAR PY 2001 VL 290 BP 185 EP 190 DI 10.1016/S0022-3115(00)00608-5 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700038 ER PT J AU Chappuis, P Tsitrone, E Mayne, M Armand, X Linke, H Bolt, H Petti, D Sharpe, JP AF Chappuis, P Tsitrone, E Mayne, M Armand, X Linke, H Bolt, H Petti, D Sharpe, JP TI Dust characterization and analysis in Tore-Supra SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE carbon; carbon deposition; carbon erosion; erosion; first wall materials; Tore Supra AB Dust produced by the last 1000 shots in Tore-Supra has been characterized. The measured mean equivalent diameter is 2.7 mum, comparable to other tokamaks. The dust surface density Varies from 2000 mg/m(2) on the bottom of the Vessel to 15 mg/mm(2) on the remaining surfaces. The carbon dust sampling in Tore-Supra revealed some nano-structures which have been identified as fullerenes. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEA Cadarache, SIPP, DRFC, EURATOM Assoc, F-13108 St Paul Durance, France. CEA Saclay, SPAM, DRCAM, F-9119 Gif Sur Yvette, France. EURATOM Assoc, Forschungszentrum Juelich, D-52425 Julich, Germany. INEEL, Idaho Falls, ID 83415 USA. RP Chappuis, P (reprint author), CEA Cadarache, SIPP, DRFC, EURATOM Assoc, Bat 506,Piece 333, F-13108 St Paul Durance, France. NR 6 TC 48 Z9 48 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 245 EP 249 DI 10.1016/S0022-3115(00)00572-9 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700049 ER PT J AU Corre, Y Giannella, R De Michelis, C Guirlet, R Azeroual, A Chareyre, E Costanzo, L Escarguel, A Gauthier, E Ghendrih, P Gunn, J Hogan, J Monier-Garbet, P Pegourie, B Pospieszczyk, A Tsitrone, E AF Corre, Y Giannella, R De Michelis, C Guirlet, R Azeroual, A Chareyre, E Costanzo, L Escarguel, A Gauthier, E Ghendrih, P Gunn, J Hogan, J Monier-Garbet, P Pegourie, B Pospieszczyk, A Tsitrone, E TI Characterisation of radiation and flux measurements on a neutraliser plate of the Tore Supra ergodic divertor SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE carbon and deuterium radiation; flux measurement; sputtering ID CARBON AB A recent extensive experimental study of impurity production and penetration for various density regimes is described. Deuterium and carbon emissions near a neutraliser plate (NP! of the Tore Supra Ergodic Divertor (ED) has been measured with an absolutely calibrated visible endoscope, for high- and low-density plasma regimes. From these radiation measurements, we have deduced an effective carbon flux, and at an order-of-magnitude estimate of the NP erosion: 50 m for the fall 1999 experimental ED campaign (approximate to 500 shots). Combining the measured carbon and deuterium fluxes, we deduce a global experimental carbon sputtering yield for the NP in the range 2 x-10(-2)-3 x 10(-1) for ohmic pulses, showing evidence of the importance of carbon self-sputtering, (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEA Cadarache, CEA Fus Controlee, EURATOM Assoc, F-13108 St Paul Durance, France. Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37830 USA. Forschungszentrum Julich Gmbh, Inst Plasma Phys, Julich, Germany. RP Corre, Y (reprint author), CEA Cadarache, CEA Fus Controlee, EURATOM Assoc, F-13108 St Paul Durance, France. RI GAUTHIER, Eric/E-1076-2011 NR 14 TC 9 Z9 9 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 MAR PY 2001 VL 290 BP 250 EP 254 DI 10.1016/S0022-3115(00)00625-5 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700050 ER PT J AU Counsell, GF Coad, JP Federici, G Krieger, K Philipps, V Skinner, CH Whyte, DG AF Counsell, GF Coad, JP Federici, G Krieger, K Philipps, V Skinner, CH Whyte, DG TI Towards an improved understanding of the relationship between plasma edge and materials issues in a next-step fusion device SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE boundary plasma; edge modelling; plasma facing materials; plasma wall interaction ID TEST REACTOR; TOKAMAK; ENERGY; TEXTOR-94; GRAPHITE; DIVERTOR; EROSION; FLUX; WALL; JET AB Long pulse lenghts, and high power and particle fluxes ensure that the biggest incremental step in a next-step fusion device will be the understanding and control of the plasma-wall interaction region. High confidence, predictive models are needed to bridge the considerable gap from existing devices. Modelling the strong, non-linear feed-back between the plasma and surface physics in this region will require significant improvements in the range and quality of diagnostic information as well as enhanced data on atomic and molecular processes and material properties. This paper highlights the key data required, discusses the need for improved diagnostics to generate these data and examines the case for future, dedicated experiments for studying plasma-wall interactions. (C) 2001 UKAEA. Published by Elsevier Science B.V. All rights reserved. C1 UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. ITER JWS Garching Co Ctr, D-85748 Garching, Germany. EURATOM Assoc, IPP, Max Planck Inst Plasmaphys, D-85748 Garching, Germany. EURATOM Assoc, Forschungszentrum Julich GmbH, Inst Plasma Phys, D-52425 Julich, Germany. Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Gen Atom Co, San Diego, CA 92186 USA. RP Counsell, GF (reprint author), UKAEA Euratom Fus Assoc, Culham Sci Ctr, D3-010, Abingdon OX14 3DB, Oxon, England. RI Krieger, Karl/F-9762-2014 OI Krieger, Karl/0000-0003-0427-8184 NR 39 TC 10 Z9 10 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 255 EP 259 DI 10.1016/S0022-3115(00)00626-7 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700051 ER PT J AU Federici, G Brooks, JN Coster, DP Janeschitz, G Kukuskhin, A Loarte, A Pacher, HD Stober, J Wu, CH AF Federici, G Brooks, JN Coster, DP Janeschitz, G Kukuskhin, A Loarte, A Pacher, HD Stober, J Wu, CH TI Assessment of erosion and tritium codeposition in ITER-FEAT SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE ITER; tritium inventory; erosion; plasma material interaction; co-deposition; B2/EIRENE ID PLASMA-FACING COMPONENTS; MODEL AB Erosion of the first-wall and divertor, and distribution of eroded material in combination with tritium codeposition (primarily with eroded carbon) over many pulses, remain critical issues for the design, operation, and safety of a long-pulse next-step fusion device, such as ITER. These issues are currently being investigated by experiments in tokamaks and in laboratories. as well as by modelling. In this study, we analyse erosion (e.g., by sputtering, ELMs, and off-normal transients) and codeposition effects in the reduced-size ITER' device, called 'ITER-FEAT, with a strike-point carbon divertor target and metallic walls, for a 'semi-detached' edge plasma regime using two-dimensional profiles of plasma edge parameters, modelled by the code B2-EIRENE. This paper accompanies the overview paper given by G. Janeschitz et al. [Plasma wall interactions in ITER-FEAT, these Proceedings]. Tritium codeposition with chemically eroded carbon still presents removal/control challenges, albeit to a somewhat lesser extent than in the 1998 ITER design, and demands efficient tritium inventory removal/control techniques. Due to numerous model uncertainties, not the least of which are the plasma solutions themselves, our intent is to provide a scoping analysis, defining trends and suggesting further research needs. (C) 2001 Elsevier Science B.V. All rights reserved. C1 ITER Garching Joint Work Site Co Ctr, D-85748 Garching, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Max Planck Inst Plasmaphys, D-85748 Garching, Germany. EFDA, Close Support Unit, D-85748 Garching, Germany. INRS Energie & Mat, Varennes, PQ J3X 1S2, Canada. RP Federici, G (reprint author), ITER Garching Joint Work Site Co Ctr, Boltzmannstr 2, D-85748 Garching, Germany. RI Coster, David/B-4311-2010 OI Coster, David/0000-0002-2470-9706 NR 22 TC 111 Z9 113 U1 0 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 260 EP 265 DI 10.1016/S0022-3115(00)00627-9 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700052 ER PT J AU Rognlien, TD Rensink, ME AF Rognlien, TD Rensink, ME TI Interactions between liquid-wall vapor and edge plasmas SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE impurity; liquid metal; first wall materials; plasma properties; theoretical modelling ID TRANSPORT AB The use of liquid walls for fusion reactors could help solve problems associated with material erosion from high plasma heat-loads and neutronic activation of structures. A key issue analyzed here is the influx of impurity ions to the core plasma from the vapor of liquid side-walls, Numerical 2D transport simulations are performed for a slab geometry which approximates the edge region of a reactor-size tokamak, Both lithium vapor (from Li or Sn-Li walls) and fluorine vapor (from Flibe walls) are considered for hydrogen edge-plasmas in the high- and low-recycling regimes. It is found that the minimum influx is from lithium with a low-recycling hydrogen plasma, and the maximum influx occurs for fluorine with a high-recycling hydrogen plasma. (C) 2001 Elsevier Science B.V, All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Rognlien, TD (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-630, Livermore, CA 94551 USA. NR 11 TC 32 Z9 32 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 312 EP 316 DI 10.1016/S0022-3115(00)00575-4 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700063 ER PT J AU Wampler, WR Whyte, DG Wong, CPC West, WP AF Wampler, WR Whyte, DG Wong, CPC West, WP TI Suppression of net erosion in the DIII-D divertor with detached plasmas SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE D111-D; DiMES; divertor erosion; erosion/deposition; detached plasma ID CARBON AB The ability to withstand disruptions makes carbon-based materials attractive for use as plasma-facing components in diverters. However, such materials suffer high erosion rates during attached plasma operation which, in high power long pulse machines, would give short component lifetimes and high tritium inventories. We present the results from recent experiments in DIII-D, in which the divertor materials evaluation system (DiMES) was used to examine erosion and deposition during short exposures to well-defined plasma conditions. These studies show that during operation with detached plasmas, produced by gas injection, net erosion is suppressed everywhere in the divertor. Net deposition of carbon with deuterium was observed at the inner and outer strike points and in the private flux region between strike points, For these low temperature plasmas (T-e < 2 eV), physical sputtering is eliminated. These results show that with detached plasmas, the location of carbon net erosion and the carbon impurity source, probably lies outside the divertor. Physical or chemical sputtering by charge-exchange neutrals or ions in the main plasma chamber is a probable source of carbon under these plasma conditions, <(c)> 2001 Elsevier Science B,V, All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Gen Atom, San Diego, CA USA. RP Wampler, WR (reprint author), Sandia Natl Labs, POB 5800,MS 1056, Albuquerque, NM 87185 USA. NR 16 TC 14 Z9 14 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 346 EP 351 DI 10.1016/S0022-3115(00)00636-X PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700070 ER PT J AU Whyte, DG West, WP Doerner, P Brooks, NH Isler, RC Jackson, GL Porter, G Wade, MR Wong, CPC AF Whyte, DG West, WP Doerner, P Brooks, NH Isler, RC Jackson, GL Porter, G Wade, MR Wong, CPC TI Reduction of divertor carbon sources in DIII-D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE carbon; chemical erosion; divertor ID RECOMBINATION; SPECTROSCOPY AB The evolution of carbon release from the DIII-D lower divertor tiles is studied using atomic and molecular spectroscopy. Newly installed virgin graphite tiles in 1992 are found to have had a chemical erosion yield, Y-chem less than or equal to 3-5%, consistent with both laboratory results and similar experiments in other totamaks. The average Y-chem measured in the DIII-D lower divertor decreased approximately a factor of ten between 1992 and 2000, The presumed cause of this reduction is the cumulative effect of >30 wall-conditioning boronizations and 10(5) s of plasma exposure, although the relative importance of these two mechanisms is unknown. This result indicates that a substantial reduction in carbon chemical erosion, and its relative importance as a source of carbon, can be obtained by long-term in situ wall conditioning techniques. The total carbon source sputtered into the DIII-D lower divertor has also apparently decreased over the same period. However, there has been no significant decrease in the average core carbon contamination with the decreasing lower divertor carbon source, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif San Diego, La Jolla, CA 92093 USA. Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Whyte, DG (reprint author), Univ Calif San Diego, 9500 Gilman Dr, La Jolla, CA 92093 USA. OI Isler, Ralph/0000-0002-5368-7200 NR 15 TC 20 Z9 20 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 MAR PY 2001 VL 290 BP 356 EP 361 DI 10.1016/S0022-3115(00)00497-9 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700072 ER PT J AU Baylor, LR Jernigan, TC Colchin, RJ Ferron, JR Wade, MR AF Baylor, LR Jernigan, TC Colchin, RJ Ferron, JR Wade, MR TI Characteristics of ELM activity and fueling efficiency of pellet injection from different locations on DIII-D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE ELM; DIII-D; pellet injection ID ASDEX UPGRADE; TOKAMAK AB Pellet injection from several different locations has been used on the DIII-D tokamak to study con fueling and transport in H-mode and L-mode plasmas. These experiments have provided a variety of conditions in which to examine the fueling efficiency and edge localized mode (ELM) interaction with pellets injected into DIII-D plasmas. The fueling efficiency, defined as the total increase in number of plasma electrons divided by the number of pellet fuel atoms, is determined by measurements of density profiles before and just after pellet injection. New injection ports on the DIII-D inner wall enable high field side (HFS) pellet injection from both the midplane and 30 cm above the midplane, These ports, in addition to the previously existing top vertical ports and outside midplane port, enable a comparison of the effect of injection location on fueling efficiency and ELM activity, We find that the ELMs triggered from HFS injected pellets and vertical HFS injected pellets are similar to the nominal background ELMs in ELMing H-mode plasmas. In contrast, the low field side (LFS) injected pellets trigger large-magnitude ELMs that lead to a strong reduction in fueling efficiency. The fueling efficiency of the HFS injected pellets is found to be significantly higher than with the LFS injected pellets and remains high even with significant heating power. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37831 USA. Gen Atom Co, San Diego, CA 92186 USA. RP Baylor, LR (reprint author), Oak Ridge Natl Lab, Div Fus Energy, POB 2009, Oak Ridge, TN 37831 USA. NR 12 TC 12 Z9 13 U1 2 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 398 EP 401 DI 10.1016/S0022-3115(00)00487-6 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700079 ER PT J AU Grisolia, C Hogan, J Ghendrih, P Loarer, T Gunn, J Monier-Garbet, P Becoulet, M Hutter, T AF Grisolia, C Hogan, J Ghendrih, P Loarer, T Gunn, J Monier-Garbet, P Becoulet, M Hutter, T TI Particle trapping in carbon walls during ICRH heating in Tore Supra SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE hydrogen trapping; Tore Supra ID DYNAMICS; TRITIUM; TOKAMAK; JET AB The role of high-energy charge exchange (CX) particles during radio-frequency (RF) heating is examined in an attempt to develop a predictive model for wall saturation and desaturation processes. Tore Supra discharges in which an apparent saturated wall, previously obtained through a succession of ohmic discharges, was transformed into a pumping wall with the application of RF heating are analyzed. Direct measurements show the increased mean energy of the CX spectrum upon application of RF heating. This leads to deeper CX neutrals penetration reaching the remaining a:C-D unsaturated layer and restoring the wall pumping efficiency. The conversion from a saturated to a pumping state with the application of RF heating, and the time scales for saturation during the ohmic and the heating phases, are reasonably well explained by several existing models. The deeper particle wall penetration observed during RF plasma experiments points to a potential mechanism which can increase tritium trapping in a fusion reactor. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEA Cadarache, DRFC, CEA, EURATOM Assoc, F-13108 St Paul Durance, France. Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37830 USA. RP Grisolia, C (reprint author), CEA Cadarache, DRFC, CEA, EURATOM Assoc, F-13108 St Paul Durance, France. NR 11 TC 0 Z9 0 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 402 EP 406 DI 10.1016/S0022-3115(00)00509-2 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700080 ER PT J AU Hillis, DL Hogan, J Coad, JP Duxbury, G Groth, M Guo, HY Horton, L Matthews, G Meigs, A Morgan, P Stamp, M von Hellermann, M AF Hillis, DL Hogan, J Coad, JP Duxbury, G Groth, M Guo, HY Horton, L Matthews, G Meigs, A Morgan, P Stamp, M von Hellermann, M TI Comparison of hydrogen and tritium uptake and retention in JET SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE JET; hydrogen retention; tritium; wall pumping; divertor; EIRENE; carbon ID DIVERTOR; EROSION; TOKAMAK AB During previous Joint European Torus (JET) deuterium-to-tritium change-over experiments, subdivertor tritium concentrations were compared with those measured at the strike point region and found to differ significantly during the first few discharges, which was correlated with wall saturation. New deuterium-to-hydrogen fueling experiments in JET have been made and are compared to these previous experiments. Rates of hydrogenic species exchange are similar to those found in previous tritium experiments. granting differences in divertor configuration and mass ratio. In the new experiments, measurements of the CD and CH molecular band intensities near the divertor strike point monitor an intermediate stage of particle exchange between the plasma and wall. The CD/CH ratio correlates well with both the plasma and subdivertor concentration. The neutral transport code EIRENE and the wall hydrogen trapping and diffusion code WDIFFUSE have been used to evaluate the wall saturation. It appears that chemically-related processes play a role in mediating the plasma-wall exchange. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37831 USA. Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Univ Strathclyde, Glasgow, Lanark, Scotland. Univ Washington, Redmond, WA 98052 USA. Max Planck Inst Plasma Phys, D-85748 Garching, Germany. EURATOM Assoc, FOM, Nieuwegein, Netherlands. RP Hillis, DL (reprint author), Oak Ridge Natl Lab, Div Fus Energy, Bldg 9201-2,MS-8072,POB 2009, Oak Ridge, TN 37831 USA. RI Groth, Mathias/G-2227-2013 NR 15 TC 5 Z9 5 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 MAR PY 2001 VL 290 BP 418 EP 422 DI 10.1016/S0022-3115(00)00439-6 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700083 ER PT J AU Mioduszewski, PK Owen, LW AF Mioduszewski, PK Owen, LW TI Local recycling coefficients and wall equilibration in tokamaks SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE first wall; hydrogen trapping; long pulse; recycling; wall pumping AB The recycling coefficient of the first wall of a fusion device is a space- and time-dependent quantity. In present analyses, it is often taken as one single parameter, without taking account of the Vast variations across the surface areas of the Vessel. The present paper is an analysis of the spatially dependent recycling coefficient as a function of time, using the DIII-D vacuum vessel as an example. In the first step, an analytical formula is constructed to simulate the recycling coefficient as a function of the trapped particle flux, based on computer simulations (W. Eckstein, Calculated Trapping Curves of D in C, Si, Garching Report IPP 9/33, October 1980). In the second step, the vessel walls are subdivided into a computational grid of 123 segments and for each segment the incident particle flux during a discharge is computed with the B2 plasma and DEGAS neutral codes. The incident particle fluxes and the recycling coefficient formula are then used to analyze the local and temporal recycling behavior of the wall. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Mioduszewski, PK (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 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 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 443 EP 447 DI 10.1016/S0022-3115(00)00512-2 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700088 ER PT J AU Miyasaka, K Tanabe, T Mank, G Finken, KH Philipps, V Walsh, DS Nishizawa, K Saze, T AF Miyasaka, K Tanabe, T Mank, G Finken, KH Philipps, V Walsh, DS Nishizawa, K Saze, T TI Tritium detection in plasma facing component by imaging plate technique SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Controlled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE tritium mapping; tritium areal distribution; imaging plate; tritium retention; plasma facing materials; plasma-surface interaction ID TEXTOR-94; RETENTION AB Tritium imaging plate technique (TIPT) has been successfully applied to measure the tritium areal distribution on various graphite tiles used as limiters in TEXTOR. It is observed that tritium distribution on the ALT-II tile is quite homogeneous and different from deuterium distribution and the tritium in redeposited layer is rather small, Such tritium distribution on the graphite tiles in TEXTOR behaves different compared to those in JET and TFTR where tritium was used as fueling gas or NBI injection. In JET and TFTR the tritium is part of the fuel and is co-deposited and retained in a similar manner as the deuterium. In a device like TEXTOR, the high-energy tritons are decoupled from the thermalized deuterons and show different behavior of retention; the main retention mechanism is deep implantation rather than co-deposition with eroded carbon on redeposition-dominated areas. It is also found that the tritium distribution measurements give useful new information on plasma-wall interactions. (C) 2001 Elsevier Science B.V. Ail rights reserved. C1 Nagoya Univ, Ctr Integrated Res Sci & Engn, Chikusa Ku, Nagoya, Aichi 4648603, Japan. Nagoya Univ, Grad Sch Engn, Dept Nucl Engn, Chikusa Ku, Nagoya, Aichi 4648603, Japan. Nagoya Univ, Radioisotope Ctr, Chikusa Ku, Nagoya, Aichi 4648603, Japan. Forschungszentrum Julich, Inst Plasmaphys, EURATOM Assoc, D-52425 Julich, Germany. Sandia Natl Labs, Dept 1111, Albuquerque, NM 87185 USA. RP Nagoya Univ, Ctr Integrated Res Sci & Engn, Chikusa Ku, Furo Cho, Nagoya, Aichi 4648603, Japan. EM tanabe@cirse.nagoya-u.ac.jp NR 8 TC 32 Z9 33 U1 0 U2 4 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 MAR PY 2001 VL 290 BP 448 EP 453 DI 10.1016/S0022-3115(00)00513-4 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700089 ER PT J AU Owen, LW Colchin, RJ Maingi, R Fenstermacher, ME Carlstrom, TN Groebner, RJ AF Owen, LW Colchin, RJ Maingi, R Fenstermacher, ME Carlstrom, TN Groebner, RJ TI Origins and spatial distributions of core fueling in the DIII-D tokamak SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE 2D model; DIII-D; Monte Carlo simulation; particle confinement time; recycling; SOL transport ID PARTICLE-TRANSPORT; DIVERTOR DISCHARGES; NEUTRAL DENSITY; MODEL; CONFINEMENT AB Analysis of DIII-D discharge data with fluid plasma and Monte Carlo neutrals transport codes reveals that core particle fueling stays relatively constant between the L-mode and the ELM-free H-mode phase immediately following the L-H transition. This indicates that in the ELM-free phase nearly all of the increase in plasma electron density comes from a decrease in the cross-field transport rate and an increase In the impurity influx. This result differs from conclusions of previous work in that the effects of the thinner H-mode scrape-off-layer do not appear to be as important in a plasma that is fueled primarily from divertor recycling as would be expected if the fueling from limiter recycling were dominant. In both L-mode and PI-mode the calculated core particle confinement times are less than, but within 50% of, the corresponding energy confinement times. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Gen Atom Co, San Diego, CA 92186 USA. RP Owen, LW (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. NR 13 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 464 EP 468 DI 10.1016/S0022-3115(00)00582-1 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700092 ER PT J AU Shimada, K Tanabe, T Causey, R Venhaus, T Okuno, K AF Shimada, K Tanabe, T Causey, R Venhaus, T Okuno, K TI Hydrogen recycling study by Balmer lines emissions in linear plasma machine TPE SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Controlled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE hydrogen recycling; Balmer lines; exothermic hydrogen occluders; endothermic hydrogen occluders; plasma-material interaction AB We have investigated the influence of target materials and temperatures on Balmer series emission in a linear plasma apparatus, Tritium Plasma Experiment (TPE), The intensities of the Balmer series emission in front of the target were higher for heavier mass target and also for lower target temperature, showing rather linear relationship between the emission intensity and hydrogen reflection coefficient, For exothermic hydrogen occluders of Ti and Ta, the intensity ratio of D beta /D alpha increased with the target temperature marliedly, whereas the intensity ratio stayed rather constant for endothermic hydrogen occluders of Ni, Cu and W. This is a clear demonstration that the target materials and temperatures modify the boundary plasma. In addition the intensity ratio D beta /D alpha is not simply a function of plasma temperature but has clear target temperature dependence. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Nagoya Univ, Ctr Integrated Res Sci & Engn, Chikusa Ku, Nagoya, Aichi 4648603, Japan. Nagoya Univ, Grad Sch Engn, Dept Nucl Engn, Chikusa Ku, Nagoya, Aichi 4648603, Japan. Sandia Natl Labs, Livermore, CA 94550 USA. Shizuoka Univ, Fac Sci, Radio Chem Res Lab, Ohya 4228529, Shizuoka 4228529, Japan. RP Nagoya Univ, Ctr Integrated Res Sci & Engn, Chikusa Ku, Furo Cho, Nagoya, Aichi 4648603, Japan. EM tanabe@cirse.nagoya-u.ac.jp NR 7 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 EI 1873-4820 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 478 EP 481 DI 10.1016/S0022-3115(00)00515-8 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700095 ER PT J AU Shu, WM Ohira, S Gentile, CA Oya, Y Nakamura, H Hayashi, T Iwai, Y Kawamura, Y Konishi, S Nishi, MF Young, KM AF Shu, WM Ohira, S Gentile, CA Oya, Y Nakamura, H Hayashi, T Iwai, Y Kawamura, Y Konishi, S Nishi, MF Young, KM TI Tritium decontamination of TFTR carbon tiles employing ultra violet light SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE tritium; carbon; waste ID DEUTERIUM; SURFACES AB Tritium decontamination on the surface of Tokamak Fusion Test Reactor (TFTR) bumper limiter tiles used during the Deuterium-Deuterium (D-D) phase of TFTR operations was investigated employing an ultra violet light source with a mean wavelength of 172 nm and a maximum radiant intensity of 50 mW/cm(2). The partial pressures of H-2, HD, C and CO2 during the UV exposure were enhanced more than twice, compared to the partial pressures before UV exposure. In comparison, the amount of O-2 decreased during the UV exposure and the production of a small amount of O-3 was observed when the UV light was turned on. Unlike the decontamination method of baking in air or oxygen, the UV exposure removed hydrogen isotopes from the tile to vacuum predominantly in forms of gases of hydrogen isotopes. The tritium surface contamination on the tile in the area exposed to the UV light was reduced after the UV exposure. The results show that the UV light with a wavelength of 172 nm can remove hydrogen isotopes from carbon-based tiles at the very surface. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Tritium Engn Lab, Tokai, Ibaraki 3191195, Japan. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Shu, WM (reprint author), Japan Atom Energy Res Inst, Tritium Engn Lab, Tokai, Ibaraki 3191195, Japan. NR 10 TC 9 Z9 10 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 MAR PY 2001 VL 290 BP 482 EP 485 DI 10.1016/S0022-3115(00)00441-4 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700096 ER PT J AU Skinner, CH Gentile, CA Ascione, G Carpe, A Causey, RA Hayashi, T Hogan, J Langish, S Nishi, M Shu, WM Wampler, WR Young, KM AF Skinner, CH Gentile, CA Ascione, G Carpe, A Causey, RA Hayashi, T Hogan, J Langish, S Nishi, M Shu, WM Wampler, WR Young, KM TI Studies of tritiated co-deposited layers in TFTR SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE TFTR; tritium retention; tritium inventory; tritium co-deposition; dust; nuclear fusion ID TRITIUM RETENTION; BUMPER LIMITER AB Plasma facing components in TFTR contain an important record of plasma wall interactions in reactor grade DT plasmas. Tiles, flakes, wall coupons, a stainless steel shutter and dust samples have been retrieved from the TFTR vessel for analysis. Selected samples have been baked to release tritium and assay the tritium content, The in-vessel tritium inventory is estimated to be 0.56 g and is consistent with the in-vessel tritium inventory derived from the difference between tritium fueling and tritium exhaust. The distribution of tritium on the limiter and vessel wall showed complex patterns of co-deposition, Relatively high concentrations of tritium were found at the top and bottom of the bumper limiter, as predicted by earlier BBQ modeling. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Sandia Natl Labs, Livermore, CA 94550 USA. Sandia Natl Labs, Albuquerque, NM 87175 USA. JAERI, Tritium Engn Lab, Ibaraki, Osaka, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Skinner, CH (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 29 TC 39 Z9 39 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 MAR PY 2001 VL 290 BP 486 EP 490 DI 10.1016/S0022-3115(00)00643-7 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700097 ER PT J AU Venhaus, T Causey, R Doerner, R Abeln, T AF Venhaus, T Causey, R Doerner, R Abeln, T TI Behavior of tungsten exposed to high fluences of low energy hydrogen isotopes SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE tungsten; tritium inventory ID PLASMA AB Tungsten is a candidate plasma facing material under investigation in a Sandia National Laboratories project conducted at Los Alamos National Laboratory. Samples of 99.95% tungsten provided by Plansee Aktiengesellschaft were exposed to 100 eV deuterium and tritium ions at a range of fluxes from 2.3 x 10(17) to 1.3 x 10(18) ions/cm(2) s for one hour at 623 K in the tritium plasma experiment. The samples were outgassed to determine the amount of retained hydrogen isotopes. The retention scaled at slightly greater than the square root of the fluence. The fractional retention was on the order of 10(-5). The data from these experiments were combined with previous results to construct a comprehensive model of the migration and retention behavior for hydrogen in tungsten, A second set of experiments involved exposing 99.95% tungsten foils provided by AESAR to 100 eV deuterons at a flux of 6 x 10(17) D/cm(2) s for 30 min at 423 and 373 K, Scanning Electron Microscopy analysis was performed on the samples to determine the effects of the plasma exposure, Unannealed samples revealed extensive blistering with many blister caps removed. Samples annealed to 1473 K showed minor blistering, and samples annealed to 1273 K showed no blistering, The SEM analysis was used in conjunction with the retention results to understand the role of annealing and defects in trapping within the tungsten. (C) 2001 Published by Elsevier Science B.V. C1 Sandia Natl Labs, Livermore, CA 94550 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Venhaus, T (reprint author), Sandia Natl Labs, MS 9402,POB 969, Livermore, CA 94550 USA. NR 9 TC 74 Z9 76 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 505 EP 508 DI 10.1016/S0022-3115(00)00443-8 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700101 ER PT J AU Wood, RD Hill, DN Hooper, EB Buchenauer, D McLean, H Wang, Z Woodruff, S Wurden, G AF Wood, RD Hill, DN Hooper, EB Buchenauer, D McLean, H Wang, Z Woodruff, S Wurden, G TI Particle control in the sustained spheromak physics experiment SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE impurity control; particle recycling AB In this paper we report on density and impurity measurements in the sustained spheromak physics experiment (SSPX) which has recently started operation. The SSPX plasma is sustained by coaxial helicity injection for a duration of 2 ms with peak toroidal currents of up to 0.5 MA. plasma-facing components consist of tungsten-coated copper to minimize sputtering, The surfaces are conditioned by a combination of baking at 150 degreesC, glow discharge cleaning, titanium gettering, and pulse-discharge cleaning with helium plasmas. In this way we achieve density control with n(e) similar to1-4 x 10(20) m(-3). However, gas input has only a weak effect on plasma density; injector current is the dominant factor. Conditioning reduces the impurity radiation to the point where it is no longer important to the energy balance, so that the lifetime of the spheromak discharge is ultimately governed by MHD which grows rapidly about 1.5-2.0 ms after helicity injection ends. (C) 2001 Elsevier Science B.V, All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Sandia Natl Labs, Livermore, CA USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Wood, RD (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. RI Wurden, Glen/A-1921-2017 OI Wurden, Glen/0000-0003-2991-1484 NR 10 TC 6 Z9 6 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 513 EP 517 DI 10.1016/S0022-3115(00)00444-X PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700103 ER PT J AU Schaffer, MJ Boedo, JA Moyer, RA Carlstrom, TN Watkins, JG AF Schaffer, MJ Boedo, JA Moyer, RA Carlstrom, TN Watkins, JG TI Large E x B convection near the divertor X-point SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE electric potential; electric field; E x B drift ID DIII-D TOKAMAK; ELECTRIC-FIELD; H-MODE; SEPARATRIX; OPERATION; PROBE AB Electric potential, electron temperature, and electron density were measured in two dimensions (R,Z) throughout the divertor and X-point in DIII-D tokamak plasmas. An electric potential hill (similar to 100 eV) and an associated electron pressure hill were discovered at the divertor X-point in L-mode plasmas. The potential hill extends previously reported divertor E x B circulation, convecting particles, energy and toroidal momentum into and out of closed magnetic surfaces, and contributes significantly to transport across the boundary. The potential is explained by classical parallel (to B) plasma physics, when the X-point T-i is clamped lower than upstream T-i. The low,X-point T-i state might be self-sustaining at low heating power due to the same E x B circulation. We speculate that if the circulation transport is incompatible with II-mode, then the spontaneous GH transition might require as a precondition that the X-point T-i become equalized on the near-separatrix magnetic surfaces, (C) 2001 Elsevier Science B.V, All rights reserved. C1 Gen Atom Co, San Diego, CA 92186 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Schaffer, MJ (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 18 TC 6 Z9 6 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 MAR PY 2001 VL 290 BP 530 EP 536 DI 10.1016/S0022-3115(00)00498-0 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700106 ER PT J AU Fenstermacher, ME Osborne, TH Petrie, TW Groebner, RJ Lasnier, CJ La Haye, RJ Leonard, AW Porter, GD Watkins, JG AF Fenstermacher, ME Osborne, TH Petrie, TW Groebner, RJ Lasnier, CJ La Haye, RJ Leonard, AW Porter, GD Watkins, JG CA DIII-D Team TI Performance of high triangularity plasmas as the volume of the secondary divertor is varied in DIII-D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE divertor; plasma properties AB This paper examines the sensitivity of edge pedestal and divertor performance parameters to changes in the volume of a secondary divertor that tends to form inside the vacuum chamber in high triangularity plasma shapes. The sensitivity was examined by varying the vertical distance of the secondary X-point from the target plate, Z(X)(S), while holding the primary,X-point height fixed. The ion delB drift was in the direction of the primary divertor. Discharges with and without active primary divertor cryo-pumping were examined. The effective rate of rise of the core density at the L-H transition increased 80% as Z(X)(S) was reduced. At high density achieved by gas injection, the col.e line-averaged density at the H-L back transition decreased by 30% as Z(X)(S) was reduced. Both of these results indicate that performance may be affected when core plasma screening of neutrals in the secondary divertor is reduced as Z(X)(S) decreases. The peak heat flux in the secondary divertor decreased as Z(X)(S) was reduced due to increased flux expansion until a threshold was leached at Z(X)(S) similar to 3 cm where it remained constant. This indicated that the high recycling character of the plasma above the target in the secondary divertor was lost when the length of the outer divertor leg was reduced below a critical value. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Gen Atom Co, San Diego, CA 92186 USA. Sandia Natl Labs, Albuquerque, NM USA. RP Fenstermacher, ME (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 6 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 MAR PY 2001 VL 290 BP 588 EP 592 DI 10.1016/S0022-3115(00)00526-2 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700118 ER PT J AU Hogan, J DeMichelis, C Monier-Garbet, P Becoulet, M Bush, C Ghendrih, P Guirlet, R Hess, W Mattioli, M Vallet, JC AF Hogan, J DeMichelis, C Monier-Garbet, P Becoulet, M Bush, C Ghendrih, P Guirlet, R Hess, W Mattioli, M Vallet, JC TI Effect of limiter recycling on measured poloidal impurity emission profiles in Tore Supra SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE impurity transport; Tore Supra AB Poloidal impurity emission profiles measured with the Tore Supra grazing incidence duochromator exhibit a complex spatial structure during ergodic divertor operation with an outboard poloidal guard limiter. As previous measurements with inboard-wall limited plasmas have shown that these profiles give important information about the ergodic field structure, so the contribution of local neon recycling from the limiter-induced plume has been modeled. This permits a discrimination of edge and core transport effects. The BBQ 3D scrape-off layer code calculates the asymmetric contribution to the emission amd MIST 1D simulation gives the symmetric part. A systematic increase is observed in the decay rate of neon emission after injection as the ergodic divertor strength is increased. The calculations permit identification of the limiter plume contribution to the profile structure, and, with this identification, the effect of the divertor to enhance impurity efflux can be seen from the decay data. (C) 2001 Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37830 USA. CEA Cadarache, St Paul Durance, France. RP Hogan, J (reprint author), Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37830 USA. NR 9 TC 5 Z9 5 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 MAR PY 2001 VL 290 BP 628 EP 632 DI 10.1016/S0022-3115(00)00519-5 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700126 ER PT J AU Porter, GD Rognlien, TD Rensink, ME Wolf, NS West, WP AF Porter, GD Rognlien, TD Rensink, ME Wolf, NS West, WP TI Particle flows in pumped DIII-D discharges SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE UEDGE; modelling; impurity AB The dynamics of particle flows in the DIII-D tokamak for two divertor configurations is considered. Fuel and intrinsic carbon impurity flows are analyzed using experimental data and 2D fluid plasma simulations. The flows in puff and pump experiments done in open and closed divertor geometries are described, It is shown that the flow of fuel particles is sensitive to divertor geometry. The pumping efficiency of the DIII-D cryopumps is a factor of 2 higher in a closed geometry than an open. The core refueling rate of an open divertor is a factor of 2 higher than that of a closed divertor. In contrast, the flow of impurity carbon particles is insensitive to divertor geometry, Both the core carbon content and the fraction of the carbon source which penetrates to the core are unchanged between open and closed diverters. In addition, the core impurity content is found to be insensitive to the amplitude of gas puffing in the simulations. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Porter, GD (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 4 TC 4 Z9 4 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 MAR PY 2001 VL 290 BP 692 EP 695 DI 10.1016/S0022-3115(00)00448-7 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700139 ER PT J AU Rensink, ME Kugel, H Maingi, R Paoletti, F Porter, GD Rognlien, TD Sabbagh, S Xu, X AF Rensink, ME Kugel, H Maingi, R Paoletti, F Porter, GD Rognlien, TD Sabbagh, S Xu, X TI Simulation of power and particle flows in the NSTX edge plasma SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE divertor modelling; NSTX; drift; sputtering; turbulence; UEDGE AB We simulate edge plasmas in NSTX double-null divertor configurations with the UEDGE two-dimensional fluid code. The carbon impurity density in the core plasma and total radiated power increase with the core heating power and the magnitude of the physical and chemical sputtering in the divertor. Up/down plasma asymmetries ale generated by classical cross-held particle drifts. With the standard toroidal magnetic field direction (ion delB drift toward the lower x-point), the highest density occurs at the lower inboard divertor plate and the highest heat flux at the upper outboard divertor plate. Simulations of three-dimensional edge plasma turbulence with the BOUT code show that anomalous radial transport at the outboard midplane should be similar in magnitude for NSTX and DIII-D, (C) 2001 Elsevier Science B.V, All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Columbia Univ, New York, NY USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Rensink, ME (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. RI Sabbagh, Steven/C-7142-2011 NR 4 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 706 EP 709 DI 10.1016/S0022-3115(00)00449-9 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700142 ER PT J AU Stangeby, PC Watkins, JG Porter, GD Elder, JD Lisgo, S Reiter, D West, WP Whyte, DG AF Stangeby, PC Watkins, JG Porter, GD Elder, JD Lisgo, S Reiter, D West, WP Whyte, DG TI Onion-skin method (OSM) analysis of DIII-D edge measurements SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE SOL plasma; divertor plasma; DIII-D; 2D model; OSM model; fluid simulation ID OFF LAYER PARAMETERS; D DIVERTOR; TEMPERATURE; DENSITY; DESIGN; FLUID AB OSM analysis provides, in principle a method for establishing the 2-D edge 'fields' of n(e), T-e, T-i, etc., which is the prerequisite for analyzing the physics processes occurring in the edge, including impurity behavior. In order to further test this method, an OSM analysis of an extensive edge database for an L-mode DIII-D discharge has been carried out, the first part of which is reported here. Consistency of the OSM results with Langmuir probe, D-alpha, and edge Thomson scattering measurements encourages further development of the method. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Toronto, Inst Aerosp Studies, Toronto, ON M3H 5T6, Canada. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Dusseldorf, D-4000 Dusseldorf, Germany. Gen Atom Co, San Diego, CA 92186 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. RP Stangeby, PC (reprint author), Univ Toronto, Inst Aerosp Studies, 4925 Dufferin St, Toronto, ON M3H 5T6, Canada. NR 14 TC 2 Z9 2 U1 2 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 733 EP 737 DI 10.1016/S0022-3115(00)00532-8 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700148 ER PT J AU Terry, JL Maqueda, R Pitcher, CS Zweben, SJ LaBombard, B Marmar, ES Pigarov, AY Wurden, G AF Terry, JL Maqueda, R Pitcher, CS Zweben, SJ LaBombard, B Marmar, ES Pigarov, AY Wurden, G TI Visible imaging of turbulence in the SOL of the Alcator C-Mod tokamak SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE scrape-off layer; turbulence; fluctuations; Alcator C-Mod; helium ID SCRAPE-OFF LAYER; PLASMA; FLUCTUATIONS; TRANSPORT; DIAGNOSTICS; BOUNDARY; BEAM AB Measurements of fluctuations in the scrape-off layer (SOL) of Alcator C-Mod plasmas were made using visible emission from the plasma edge. Line emissions from a local gas jet of He atoms were imaged along radially separated, toroidally viewing chords and provided local measurements (DeltaR, DeltaZ = 3.4 mm, R Delta phi similar to 20 mm) of density fluctuations. The RMS emission fluctuation amplitudes, normalized by the average emission, ranged from 10% to 60%, depending on distance from the separatrix, and increased sharply beyond rho (from) = 20 mm. These intensity fluctuations imply that radial profile of the normalized RMS density fluctuations varies from similar to 20% to 90%. Typical fluctuation spectra show turbulence out to frequencies of similar to 150 kHz, although most of the spectral power is below 20 kHz. The radial correlation length for the <20 kHz fluctuations is 7 mm, No essential differences were seen in the SOL fluctuations when plasmas with 'Enhanced D-alpha' (EDA) H-mode confinement were compared with those having L-mode confinement. In addition, fluctuations in 'natural' D-alpha light, due to recycling at an outboard poloidal limiter, were imaged by a gated fast-framing camera and provided measurements of the poloidal size scale of the SOL fluctuations. Snapshots of D-alpha emission were obtained with exposures of 2 and 10 mus. Typical fluctuation size in the poloidal dimension was 0.01-0.03 m. These striations/fluctuations were randomly located in the successive gated frames taken at 1000 Hz, as expected for edge turbulence. (C) 2001 Elsevier Science B.V. All rights reserved. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Terry, JL (reprint author), MIT, Plasma Sci & Fus Ctr, Room NW 17-176,175 Albany St, Cambridge, MA 02139 USA. RI Wurden, Glen/A-1921-2017 OI Wurden, Glen/0000-0003-2991-1484 NR 17 TC 57 Z9 57 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 MAR PY 2001 VL 290 BP 757 EP 762 DI 10.1016/S0022-3115(00)00453-0 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700153 ER PT J AU Wade, MR Houlberg, WA Baylor, LR West, WP Baker, DR AF Wade, MR Houlberg, WA Baylor, LR West, WP Baker, DR TI Low-Z impurity transport in DIII-D - observations and implications SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE impurity transport; impurity effects ID PARTICLE-TRANSPORT; D TOKAMAK; CONFINEMENT; RATIO; MODE; ION AB Impurity transport studies on DIII-D have revealed transport phenomena that are qualitatively consistent with that expected from turbulence transport theory in some cases and neoclassical transport theory in other cases. The transport model proposed here, which assumes that the total impurity transport is a linear sum of turbulence-driven transport and neoclassical transport, is shown to reproduce many of these observed features. This transport model is then applied to burn condition calculations, revealing that profile effects associated with neoclassical transport have a large effect on the maximum allowable impurity fraction in machines based on achieving neoclassical transport levels. (C) 2001 Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Gen Atom Co, San Diego, CA 92186 USA. RP Wade, MR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 9 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 MAR PY 2001 VL 290 BP 773 EP 777 DI 10.1016/S0022-3115(00)00499-2 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700156 ER PT J AU Watkins, JG Stangeby, P Boedo, JA Carlstrom, TN Lasnier, CJ Moyer, RA Rudakov, DL Whyte, DG AF Watkins, JG Stangeby, P Boedo, JA Carlstrom, TN Lasnier, CJ Moyer, RA Rudakov, DL Whyte, DG TI Comparison of Langmuir probe and Thomson scattering measurements in DIII-D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE plasma properties; experimental techniques; modelling ID D DIVERTOR AB In this paper, we compare measurements of density and electron temperature made by target plate Langmuir probes (LP) and the divertor Thomson scattering (DTS) diagnostics in the DIII-D tokamak divertor. By examining low-density, ohmic ELM-free discharges, we can use the simple standard electron thermal conduction model (SETC) to relate the measurements at different but closely spaced locations. For this nearly sheath-limited regime, we have derived a correction factor of similar to 0.8 for local LP temperature values based on the SETC model. We have sorted the DTS measurements above the plate onto flux surfaces, calculated the connection length to the plate, and constructed parallel density and temperature profiles for comparisons along the magnetic field lines. Measurements from both diagnostics are consistent with the predictions of this very simple model. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Gen Atom 13 350, San Diego, CA 92186 USA. Univ Toronto, Inst Aerosp Studies, San Diego, CA 92186 USA. Univ Calif San Diego, San Diego, CA 92186 USA. Lawrence Livermore Natl Lab, San Diego, CA 92186 USA. RP Watkins, JG (reprint author), Sandia Natl Labs, Gen Atom 13 350, POB 85608, San Diego, CA 92186 USA. RI Rudakov, Dmitry/K-2834-2012 NR 7 TC 7 Z9 7 U1 2 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 MAR PY 2001 VL 290 BP 778 EP 782 DI 10.1016/S0022-3115(00)00534-1 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700157 ER PT J AU West, WP Porter, GD Evans, TE Stangeby, P Brooks, NH Fenstermacher, ME Isler, RC Rognlien, TD Wade, MR Whyte, DG Wolf, NS AF West, WP Porter, GD Evans, TE Stangeby, P Brooks, NH Fenstermacher, ME Isler, RC Rognlien, TD Wade, MR Whyte, DG Wolf, NS TI Modeling of carbon transport in the divertor and SOL of DIII-D during high performance plasma operation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE impurity transport; impurity source; fluid modeling; carbon; DIII-D ID CODE AB The UEDGE modeling code has been used to study the effect of varying the carbon yield from the plasma facing surfaces on the core plasma carbon contamination in DIII-D. The model of the lower single-null, ELMing H-mode plasma shows a remarkably weak dependence of the core carbon concentration over an approximate factor of two variation in the source. This weak dependence is in agreement with the analysis of spectroscopic data from DIII-D [1]. Examination of the carbon transport shows a general flow pattern of carbon as follows: (1) parallel flow from the diverters to the near scrape off layer (SOL) near the separatrix, (2) cross field diffusion from the near SOL to the far SOL (near the wall), and (3) parallel flow from the far SOL to the far region of the inner divertor. The carbon flux from the diverters to the near SOL drops as the sputtering rate is reduced. In the far SOL, background plasma parameters adjust in small ways to produce an increasing carbon density with decreasing sputtering yield. This increasing density of carbon in the far SOL is consistent with a reduction in the parallel velocity of carbon ions flowing from the far SOL back to the inner divertor. Since the carbon density near the separatrix is constant as the sputtering yield is reduced, the increasing density in the far SOL reduces the radial gradient and therefore the diffusive radial flow. A balance in the outward radial diffusive flow from the near SOL and the how from the divertor into the near SOL maintains the carbon density in the near SOL nearly constant, even though the carbon throughput changes. (C) 2001 Published by Elsevier Science B.V. C1 Gen Atom Co, San Diego, CA 92186 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Toronto, Inst Aerosp Studies, N York, ON M3H 5T6, Canada. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Calif San Diego, San Diego, CA 92103 USA. RP West, WP (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. OI Isler, Ralph/0000-0002-5368-7200 NR 12 TC 3 Z9 3 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 MAR PY 2001 VL 290 BP 783 EP 787 DI 10.1016/S0022-3115(00)00535-3 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700158 ER PT J AU Ghendrih, P Becoulet, M Costanzo, L Corre, Y Grisolia, C Grosman, A Guirlet, R Gunn, J Loarer, T Monier-Garbet, P Mank, G Reichle, R Vallet, JC Zabiego, M Azeroual, A Bucalossi, J Devynck, P De Michelis, C Finken, KH Hogan, J Laugier, F Nguyen, F Pegourie, B Saint-Laurent, F Schunke, B AF Ghendrih, P Becoulet, M Costanzo, L Corre, Y Grisolia, C Grosman, A Guirlet, R Gunn, J Loarer, T Monier-Garbet, P Mank, G Reichle, R Vallet, JC Zabiego, M Azeroual, A Bucalossi, J Devynck, P De Michelis, C Finken, KH Hogan, J Laugier, F Nguyen, F Pegourie, B Saint-Laurent, F Schunke, B CA Tore Supra Team TI Control of divertor geometry and performance of the ergodic divertor of Tore Supra SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Controlled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE divertor; ergodic divertor ID TOKAMAKS; ITER AB Experimental evidence of the location of the ergodic divertor separatrix is shown to agree with the predicted value given by codes. Variation of this position modifies the divertor tightness, defined as the ratio of the divertor to core density. This effect is governed by laminar transport, i.e., transport proportional to the magnitude of the perturbation. Operation with feedback control of the divertor temperature allows one to optimise the choice of injected impurity species. At 10 eV divertor temperature, nitrogen is shown to lead to the largest decrease in energy flux to the divertor at lowest contribution to Z(eff) Parallel energy fluxes as low as 2 MW m(-2) are thus achieved on the target plates. For this impurity, radiation is localised in the divertor volume thus leading to radiation compression close to 10. The ergodic divertor appears as a powerful tool to control plasma-wall interaction with no loss of core confinement or plasma current. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEN Cadarache, Assoc Euratom CEA Fus, F-13108 St Paul Les Durance, France. Forschungszentrum Julich, EURATOM Assoc, Inst Plasmaphys, D-52425 Julich, Germany. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP CEN Cadarache, Assoc Euratom CEA Fus, F-13108 St Paul Les Durance, France. EM ghendrih@drfc.cad.cea.fr RI Artaud, Jean-Francois/G-8480-2011; ANIEL, Thierry/G-8734-2011; Dumont, Remi/D-3840-2009; Artaud, Jean-Francois/J-2068-2012 OI ANIEL, Thierry/0000-0002-2598-9551; NR 10 TC 6 Z9 6 U1 0 U2 1 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 MAR PY 2001 VL 290 BP 798 EP 804 DI 10.1016/S0022-3115(00)00536-5 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700161 ER PT J AU Pitcher, CS Boswell, CJ Chung, T Goetz, JA LaBombard, B Lipschultz, B Rice, JE Stotler, DP Terry, JL AF Pitcher, CS Boswell, CJ Chung, T Goetz, JA LaBombard, B Lipschultz, B Rice, JE Stotler, DP Terry, JL TI The effect of baffling on divertor leakage in Alcator C-Mod SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE Alcator C-Mod; 1D model; divertor pumping ID SCRAPE-OFF LAYER; ASDEX UPGRADE; PLASMA; GEOMETRY; JET; DISCHARGES AB The effect of divertor baffling on Alcator C-Mod has been investigated using a novel divertor bypass. The bypass allows in situ variations in the leakage conductance between the divertor plenum and the main chamber. The experimental results, supported by simple modeling? suggest that C-Mod operates in a regime where the leakage flux is independent of the leakage conductance. The relatively large leakage flux is driven by the high gas pressure in the C-Mod divertor and is 'flux-limited' by the atom creation rate at the target plate and the atom escape probability from the divertor plasma. These results, along with results from other tokamaks, suggest that baffling needs to be significantly tighter than had been previously thought to ensure low levels of divertor leakage and maximum divertor pressures. (C) 2001 Elsevier Science B.V. All rights reserved. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Pitcher, CS (reprint author), MIT, Plasma Sci & Fus Ctr, NW17-111,175 Albany St, Cambridge, MA 02139 USA. RI Lipschultz, Bruce/J-7726-2012; Stotler, Daren/J-9494-2015 OI Lipschultz, Bruce/0000-0001-5968-3684; Stotler, Daren/0000-0001-5521-8718 NR 22 TC 8 Z9 8 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 812 EP 819 DI 10.1016/S0022-3115(00)00537-7 PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700163 ER PT J AU Fielding, SJ Cohen, RH Helander, P Ryutov, DD AF Fielding, SJ Cohen, RH Helander, P Ryutov, DD TI Divertor target heat load reduction by electrical biasing, and application to COMPASS-D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE biasing; SOL plasma; transverse transport ID ASYMMETRIES AB A toroidally asymmetric potential structure in the scrape-off layer (SOL) plasma may be formed by toroidally distributed electrical biasing of the divertor target tiles. The resulting E x B convective motions should increase the plasma radial transport in the SOL and thereby reduce the heat load at the divertor [R.H. Cohen, D.D. Ryutov, Nucl. Fus. 37 (1997) 621]. In this paper, we develop theoretical modelling and describe the implementation of this concept to the COMPASS-D divertor. We show that a strong magnetic shear near the X-point should cause significant squeezing of the convective cells preventing convection from penetrating above the X-point. This should result in reduced heat load at the divertor target without increasing the radial transport in the portion of the SOL in direct contact with the core plasma, potentially avoiding any confinement degradation. Implementation of divertor biasing is in hand on COMPASS-D involving insulation of, and modifications to, the present divertor tiles. Calculations based on measured edge parameters suggest that modest currents similar to8 A/tile are required, at up to 150 V, to drive the convection. A technical test is preceding full bias experiments. (C) 2001 UKAEA. Published by Elsevier Science B.V. All rights reserved. C1 UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Fielding, SJ (reprint author), UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. NR 5 TC 4 Z9 4 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 MAR PY 2001 VL 290 BP 859 EP 862 DI 10.1016/S0022-3115(00)00651-6 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700172 ER PT J AU Groth, M Andrew, P Fundamenski, W Guo, HY Hillis, DL Hogan, JT Horton, LD Matthews, GF Meigs, AG Morgan, PM Stamp, MF von Hellermann, M AF Groth, M Andrew, P Fundamenski, W Guo, HY Hillis, DL Hogan, JT Horton, LD Matthews, GF Meigs, AG Morgan, PM Stamp, MF von Hellermann, M TI Noble gas enrichment studies at JET SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE particle compression; impurity enrichment; divertor leakage; ionization mean free path ID SCRAPE-OFF LAYER; FLOW AB Adequate helium exhaust has been achieved in reactor-relevant ELMy H-mode plasmas in JET performed in the MKII AP and MKII GB divertor geometry. The divertor-characteristic quantities of noble gas compression and enrichment have been experimentally inferred from Charge Exchange Recombination Spectroscopy measurements in the core plasma, and from spectroscopic analysis of a Penning gauge discharge in the exhaust gas. The retention of helium was found to be satisfactory for a next-step device, with enrichment factors exceeding 0.1. The helium enrichment decreases with increasing core plasma density, while the neon enrichment has the opposite behaviour, Analytic and numerical analyses of these plasmas using the divertor impurity code package DIVIMP/NIMBUS support the explanation that the enrichment of noble gases depends significantly on the penetration depth of the impurity neutrals with respect to the fuel atoms. Changes of the divertor plasma configuration and divertor geometry have no effect on the enrichment. (C) 2001 Published by Elsevier Science B.V. C1 Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Univ Manchester, UMIST, Manchester M60 1QD, Lancs, England. Univ Wisconsin, Madison, WI USA. Univ Washington, Redmond Plasma Phys Lab, Seattle, WA 98195 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Max Planck Inst Plasma Phys, Garching, Germany. Rijnhizen, Inst Plasma Phys, FOM, Nieuwegein, Netherlands. RP Groth, M (reprint author), Culham Res Ctr, Abingdon OX14 3EA, Oxon, England. RI Groth, Mathias/G-2227-2013 NR 18 TC 3 Z9 3 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 867 EP 871 DI 10.1016/S0022-3115(00)00652-8 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700174 ER PT J AU Guirlet, R Hogan, J Corre, Y De Michelis, C Escarguel, A Hess, W Monier-Garbet, P Schunke, B AF Guirlet, R Hogan, J Corre, Y De Michelis, C Escarguel, A Hess, W Monier-Garbet, P Schunke, B TI Spectroscopic study of neon emission and retention in the Tore Supra ergodic divertor SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE divertor material; impurity; plasma-material interaction AB In order to assess the capability of the Tore Supra ergodic divertor (ED) to retain impurities in the low confinement edge region, spectroscopic observations of a divertor neutraliser plate are reported. The neutral neon density is deduced from these measurements: it increases strongly (up to 1.5 x 10(17) m(-3) per injected Pa 1) when the plasma approaches detachment. The central neon density is approximately independent of the plasma edge conditions. A 2D model confirms the relatively weak measured dependence of the neutral neon penetration on edge electron density and temperature. Comparison of BBQ (3D scrape-off layer Monte-Carlo code) results with 1D impurity radial transport modelling suggests a possible mechanism for the observed weak dependence of core content on edge impurity influx: enhanced exchange between the ergodized layer of the core and the neutraliser region. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CE Cadarache, EURATOM Assoc, CEA Fus Controlee, F-13108 St Paul Durance, France. Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37831 USA. RP Guirlet, R (reprint author), CE Cadarache, EURATOM Assoc, CEA Fus Controlee, F-13108 St Paul Durance, France. NR 9 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 872 EP 876 DI 10.1016/S0022-3115(00)00653-X PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700175 ER PT J AU Mahdavi, MA Wade, MR Watkins, JG Lasnier, CJ Luce, T Allen, SL Hyatt, AW Baxi, C Boedo, JA Bozek, AS Brooks, NH Colchin, RJ Evans, TE Fenstermacher, ME Friend, ME O'Neill, RC Isler, RC Kellman, AG Leonard, AW Maingi, R Moyer, RA Petrie, TW Porter, GD Schaffer, MJ Skinner, S Stambaugh, RD Stangeby, PC West, WP Whyte, DG Wolf, NS AF Mahdavi, MA Wade, MR Watkins, JG Lasnier, CJ Luce, T Allen, SL Hyatt, AW Baxi, C Boedo, JA Bozek, AS Brooks, NH Colchin, RJ Evans, TE Fenstermacher, ME Friend, ME O'Neill, RC Isler, RC Kellman, AG Leonard, AW Maingi, R Moyer, RA Petrie, TW Porter, GD Schaffer, MJ Skinner, S Stambaugh, RD Stangeby, PC West, WP Whyte, DG Wolf, NS TI Initial performance results of the DIII-D Divertor 2000 SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Controlled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE Divertor; DIII-D ID D TOKAMAK; PLASMA AB A major upgrade of the DIII-D divertor, with the goal of enhancing impurity and density control and increasing the thermal pulse length limit of advanced tokamak (AT) plasmas has been successfully completed and commissioned. The integrated system that includes independent cryopumps at both the inner and the outer legs of the divertor, private flux region and outboard baffles, and improved graphite divertor armor, has been successfully applied to a variety of plasma conditions. Comparison of similar discharges before and after the upgrades show that with the new divertor the core plasma neutral source and carbon content are lower by as much as 50%. Calculations supported by preliminary infrared (IR) camera measurements show that the new graphite armor design increases the limit on the discharge duration, due to temperature of the tile edges reaching sublimation point, by an order of magnitude. With the new system we have been able to control the density of high confinement H-mode plasmas to less than 1/3 of the Greenwald limit. It is observed that with divertor pumping during the current ramp phase the wall particle inventory and consequently the density rise after the H-mode transition can be significantly reduced. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Calif San Diego, San Diego, CA 92103 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Toronto, Inst Aerosp Studies, Toronto, ON, Canada. RP Gen Atom Co, POB 85608, San Diego, CA 92186 USA. EM mahdavi@fusion.gat.com OI Isler, Ralph/0000-0002-5368-7200 NR 13 TC 12 Z9 12 U1 1 U2 3 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 MAR PY 2001 VL 290 BP 905 EP 909 DI 10.1016/S0022-3115(00)00500-6 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700182 ER PT J AU Monier-Garbet, P DeMichelis, C Ghendrih, P Grisolia, C Grosman, A Guirlet, R Gunn, J Loarer, T Bush, CE Clement, C Corre, Y Costanzo, L Schunke, B Vallet, JC AF Monier-Garbet, P DeMichelis, C Ghendrih, P Grisolia, C Grosman, A Guirlet, R Gunn, J Loarer, T Bush, CE Clement, C Corre, Y Costanzo, L Schunke, B Vallet, JC TI High radiation from intrinsic and injected impurities in Tore Supra ergodic divertor plasmas SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE divertor radiation; impurity screening; power loading ID FEEDBACK; TOKAMAK AB We report experiments aimed at comparing several impurity mixtures (C, O, Cl, N, Ne, Ar) regarding their capability to reduce the power load on the divertor target plates. The divertor conditions required for each mixture to minimise the parallel power flux are determined, along with the resulting core effective charge Z(eff) and volume averaged density. The radiation efficiency (ratio of edge radiation to plasma core contamination) of intrinsic carbon is found to increase with the total injected power. In the impurity injection experiments, nitrogen is found to be the best choice to reduce the power flux to the target plates: it has the same characteristics as CIO radiation (low core contamination), and it can be controlled. The low Z(eff) observed in this case is attributed to the large value of the screening of the radiating ionisation stages of the impurity. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Assoc Euratom, CEA Fus Controlee, Ctr Etud Cadarache, DRFC, F-13108 St Paul Durance, France. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Monier-Garbet, P (reprint author), Assoc Euratom, CEA Fus Controlee, Ctr Etud Cadarache, DRFC, F-13108 St Paul Durance, France. NR 12 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 MAR PY 2001 VL 290 BP 925 EP 929 DI 10.1016/S0022-3115(00)00459-1 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700186 ER PT J AU Petrie, TW Greenfield, CM Grobener, RJ Hyatt, AW La Haye, RJ Leonard, AW Mahdavi, MA Osborne, TH Schaffer, MJ Thomas, DM West, WP Allen, SL Fenstermacher, ME Lasnier, CJ Porter, GD Wolf, NS Watkins, JG Rhodes, TL AF Petrie, TW Greenfield, CM Grobener, RJ Hyatt, AW La Haye, RJ Leonard, AW Mahdavi, MA Osborne, TH Schaffer, MJ Thomas, DM West, WP Allen, SL Fenstermacher, ME Lasnier, CJ Porter, GD Wolf, NS Watkins, JG Rhodes, TL CA DIII-D Team TI The effect of divertor magnetic balance on H-mode performance in DIII-D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE divertor asymmetry; geometry effects; heat flux to divertor ID THERMAL INSTABILITIES; TOKAMAK AB We report on recent experiments for which the magnetic balance of highly triangular (delta approximate to 0.8), unpumped H-mode plasmas was varied. Changes in divertor heat loading and particle flux were observed when the magnetic configuration was varied from a balanced double-null (DN) divertor to a slightly unbalanced DN divertor. For attached plasmas, the variation in heat flux sharing between diverters is very sensitive near balanced DN. This sensitivity can be shown to be consistent with the measured scrape-off width of the parallel divertor heat flux density, lambda (q parallel to). At magnetic balance Eve find that the peak heat flux density at the divertor in the VB ion drift direction is twice that of the other divertor. Most of the heat flux go to the outboard divertor targets in a balanced double-null, where the peak heat flux density at the outer divertor targets may exceed that of the inner divertor targets by tenfold. However, the variation of the peak particle flux density between diverters is less sensitive to changes in magnetic balance. These particle and heat flux 'asymmetries' in DN plasmas are consistent with the presence of E x B poloidal particle drifts in the scrape-off layer and private flux region [1]. Regardless of how the diverters were magnetically balanced, D-2 gas puffing always reduced energy confinement to the range tau (E)/tau (E89P) approximate to 1.3-1.6, When this energy confinement range was reached, tau (E)/tau (E89P) remained nearly constant up to near the H-mode density limit. (C) 2001 Elsevier Science B.V. All rights reserved. C1 DIII D Team Gen Atom, San Diego, CA 92186 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. RP Petrie, TW (reprint author), DIII D Team Gen Atom, POB 85608, San Diego, CA 92186 USA. NR 16 TC 22 Z9 22 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 MAR PY 2001 VL 290 BP 935 EP 939 DI 10.1016/S0022-3115(00)00492-X PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700188 ER PT J AU Stotler, DP Pitcher, CS Boswell, CJ Chung, TK LaBombard, B Lipschultz, B Terry, JL Kanzleiter, RJ AF Stotler, DP Pitcher, CS Boswell, CJ Chung, TK LaBombard, B Lipschultz, B Terry, JL Kanzleiter, RJ TI Modeling of Alcator C-Mod divertor baffling experiments SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE Alcator C-Mod; DEGAS code; neutral gas modeling ID NEUTRAL GAS-TRANSPORT AB A specific Alcator C-Mod discharge from the series of divertor baffling experiments is simulated with the DEGAS2 Monte Carlo neutral transport code. A simple two-point plasma model is used to describe the plasma Variation between Langmuir probe locations. A range of conductances for the bypass between the divertor plenum and the main chamber are considered. The experimentally observed insensitivity of the neutral current flowing through the bypass and of the D-alpha emissions to the magnitude of the conductance is reproduced. The current of atoms in this regime is being limited by atomic physics processes and not bypass conductance. The simulated trends in divertor pressure, bypass current, and D-alpha emission agree only qualitatively with the experimental measurements, however. Possible explanations for the quantitative differences are discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Rensselaer Polytech Inst, Troy, NY 12181 USA. RP Stotler, DP (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Lipschultz, Bruce/J-7726-2012; Stotler, Daren/J-9494-2015 OI Lipschultz, Bruce/0000-0001-5968-3684; Stotler, Daren/0000-0001-5521-8718 NR 18 TC 13 Z9 13 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 967 EP 971 DI 10.1016/S0022-3115(00)00542-0 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700194 ER PT J AU Strachan, JD Erents, K Fundamenski, W von Hellermann, M Horton, L McCracken, G Spence, J Stamp, M Zastrow, KD AF Strachan, JD Erents, K Fundamenski, W von Hellermann, M Horton, L McCracken, G Spence, J Stamp, M Zastrow, KD TI JET methane screening experiments SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE carbon; plasma properties; impurities ID C-MOD TOKAMAK; CODE; PLASMAS; DIVIMP AB Methane screening experiments were performed in JET L-Mode plasmas. Potentially, methane pulling quantifies the SOL processes governing the intrinsic carbon, its penetration to the plasma core, and its removal to the divertor. We measured the perturbations to the core and the SOL plasmas as a function of CD4 and D-2 injection rates. The deduced screening was independent of the methane injection rate indicating that the methane itself did not significantly perturb the deduced screening. Identification of appropriate reference plasmas is important, For JET L-Modes, the reference plasma should have enough deuterium puffing to achieve the same density as that which occurred with the methane. The screening results are susceptible to systematic errors in the visible and charge exchange determination of the core carbon density. For JET, these two measurements yield screening values that differ by a 'factor-of-three'. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. UKAEA, Culham, England. RP Strachan, JD (reprint author), Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. NR 13 TC 10 Z9 10 U1 2 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 972 EP 975 DI 10.1016/S0022-3115(00)00543-2 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700195 ER PT J AU Allen, SL Boedo, JA Bozek, AS Brooks, NH Carlstrom, TN Casper, TA Colchin, RJ Evans, TE Fenstermacher, ME Friend, ME Isler, RC Jayakumar, R Lasnier, CJ Leonard, AW Mahdavi, MA Maingi, R McKee, GR Moyer, RA Murakami, M Osborne, TH O'Neill, RC Petrie, TW Porter, GD Ramsey, AT Schaffer, MJ Stangeby, PC Stambaugh, RD Wade, MR Watking, JG West, WP Whyte, DG Wolf, NS AF Allen, SL Boedo, JA Bozek, AS Brooks, NH Carlstrom, TN Casper, TA Colchin, RJ Evans, TE Fenstermacher, ME Friend, ME Isler, RC Jayakumar, R Lasnier, CJ Leonard, AW Mahdavi, MA Maingi, R McKee, GR Moyer, RA Murakami, M Osborne, TH O'Neill, RC Petrie, TW Porter, GD Ramsey, AT Schaffer, MJ Stangeby, PC Stambaugh, RD Wade, MR Watking, JG West, WP Whyte, DG Wolf, NS TI Experiments and computational modeling focused on divertor and SOL optimization for advanced tokamak operation on DIII-D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE divertor; SOL; DIII-D ID RADIATIVE DIVERTOR; JT-60U; LAYER AB We present the results from DIII-D experiments and modeling focused on the divertor issues of an 'Advanced Tokamak' (AT). Operation at high plasma pressure beta with good energy confinement H requires core and divertor plasma shaping and current profile J(r) control with ECH current drive. Transport modeling indicates that the available DIII-D ECH power determines a density and temperature regime for sustained DIII-D AT experiments. We demonstrate that a high-delta, unbalanced double null divertor with cryopumping (D-2000) is a flexible AT divertor. Impurity levels in AT experiments have been reduced by careful alignment of the divertor tiles; this, in turn has changed the time evolution of the core J(r) profiles. New physics has been observed near the X-point and private flux regions, including flow reversal and recombination, that is important in understanding and controlling the flows and thereby the radiation in the divertor region, which reduces the divertor heat flux. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Gen Atom Co, LLNL, San Diego, CA 92186 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Wisconsin, Madison, WI 53706 USA. Univ Toronto, Inst Aerosp Studies, N York, ON M3H 5T6, Canada. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Allen, SL (reprint author), Gen Atom Co, LLNL, POB 85608, San Diego, CA 92186 USA. OI Isler, Ralph/0000-0002-5368-7200 NR 14 TC 4 Z9 4 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 MAR PY 2001 VL 290 BP 995 EP 1001 DI 10.1016/S0022-3115(00)00501-8 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700200 ER PT J AU Osborne, TH Mahdavi, MA Chu, M Fenstermacher, ME La Haye, R Leonard, AW McKee, G Petrie, TW Rettig, C Wade, M Watkins, J AF Osborne, TH Mahdavi, MA Chu, M Fenstermacher, ME La Haye, R Leonard, AW McKee, G Petrie, TW Rettig, C Wade, M Watkins, J CA DIII-D Team TI Gas puff fueled H-mode discharges with good energy confinement above the Greenwald density limit on DIII-D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE density limit; DIII-D; edge plasma ID TOKAMAK AB Tokamak discharges with electron densities as high as 1.4 times the Greenwald density, and good energy confinement, H-ITER89P = 1.9, were obtained with D-2 gas puffing on DIII-D. The divertor configuration of these discharges, low triangularity with pumping of the private flux region, was important in avoiding a transition to the L-mode or Type III ELM regimes in which energy confinement was reduced. Although these discharges show a decrease in H-mode pedestal energy at high density through reduction in the edge pressure gradient, peaking of the density profile compensated for the effect of this decrease on the overall stored energy. Spontaneous density profile peaking occurred under conditions which enhance the neoclassical Ware pinch. The high density phase was terminated by an internal MHD event that has the characteristics of a neoclassical tearing mode. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Gen Atom Co, San Diego, CA 92138 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Wisconsin, Madison, WI 53706 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Osborne, TH (reprint author), Gen Atom Co, 13-412,POB 85608, San Diego, CA 92138 USA. NR 17 TC 20 Z9 20 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 1013 EP 1017 DI 10.1016/S0022-3115(00)00660-7 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700203 ER PT J AU Mitteau, R Chappuis, P Ghendrih, P Grosman, A Guilhem, D Gunn, J Hogan, J Lipa, M Martin, G Schlosser, J Tsitrone, E AF Mitteau, R Chappuis, P Ghendrih, P Grosman, A Guilhem, D Gunn, J Hogan, J Lipa, M Martin, G Schlosser, J Tsitrone, E TI Self-shadowing, gaps and leading edges on Tore Supra's inner first wall SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE e-folding length; geometry effect; Tore Supra; heat flux AB Operation with the actively cooled inner first wall of Tore Supra shows that even such a large area limiter is subjected to anomalous heat deposition where the plasma contacts the limiter. This can be modelled by a parallel convective heat flux with a e-folding length of the order of a millimetre, In some extreme cases, associated with lower hybrid heating in a low density plasma, the situation could degenerate into a runaway situation associated with large carbon influx into the discharge and ending with the rupture of elements. The analysis of the heat flux deposition on this limiter is complicated by the need to take shadowing effects into account, which are becoming significant because of the small scale phenomenon involved. It is shown that only a small fraction of the front faces is wetted by the parallel heat flux and that very disparate heat fluxes co-exists on each element. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEA Fus Controlee, EURATOM Assoc, Ctr Etude Cadarache, DRFC,SIPP, F-13108 St Paul Durance, France. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Mitteau, R (reprint author), CEA Fus Controlee, EURATOM Assoc, Ctr Etude Cadarache, DRFC,SIPP, Bat 507,Bur 203, F-13108 St Paul Durance, France. NR 13 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 1036 EP 1039 DI 10.1016/S0022-3115(00)00661-9 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700207 ER PT J AU Burtseva, T Hassanein, A Ovchinnikov, I Titov, V AF Burtseva, T Hassanein, A Ovchinnikov, I Titov, V TI Study of brittle destruction and erosion mechanisms of carbon-based materials during plasma instabilities SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE divertor; erosion; carbon-based materials; disruption; brittle destruction ID SIMULATION AB Erosion damage due to plasma instabilities such as hard disruptions, edge-localized modes, and vertical displacement events remains a major obstacle to successful realization of the tokamak-reactor concept. As a result of these plasma instabilities, intense plasma energy that is deposited during short periods can cause severe erosion, structural damage, and surface modifications of the plasma-facing materials. Experimental work is being carried out at the high-power VIKA-93 plasma-gun facility in the Efremov Institute, Russia. Interesting results were obtained during preliminary heating of the samples (to 1200 degreesC) and use of maximum plasma gun parameters, i.e., E-in = 30 MJ/m(2), tau = 360 mus. In all samples, a large increase in weight loss (up to 80%) was observed during plasma bombardment when preheating was used. Scanning electron microscope investigations have demonstrated a considerable evolution of surface recrystallization processes, especially for preheated CFC materials. Significant differences among various carbon materials are found for specimens with and without preliminary heating. (C) 2001 Elsevier Science B.V. All rights reserved. C1 STC SINTEZ DV, Efremov Inst Electrophys Apparatus, St Petersburg 196641, Russia. Argonne Natl Lab, Argonne, IL 60439 USA. RP Burtseva, T (reprint author), STC SINTEZ DV, Efremov Inst Electrophys Apparatus, 189 631, St Petersburg 196641, Russia. NR 6 TC 13 Z9 13 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 1059 EP 1063 DI 10.1016/S0022-3115(00)00663-2 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700211 ER PT J AU Hassanein, A Konkashbaev, I AF Hassanein, A Konkashbaev, I TI Macroscopic erosion of plasma facing and nearby components during plasma instabilities: the droplet shielding phenomenon SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE disruption; MHD; erosion; splashing; ablation; shielding; lifetime; HEIGHTS package ID DISRUPTION AB Erosion losses due to ablation during a plasma disruption can be extremely high. This call severely limit divertor system lifetime to only a few disruptions. Ablation is mass loss in the form of macroscopic particles (MPs), i.e., droplets of liquid metals or large pieces (grains or crystallites) of non-melting materials such as carbon-based materials. Results of self-consistent magnetohydrodynamic (MHD) calculations are obtained that couple the dynamics of both vapor cloud and MP interaction to incoming ions and electrons from the collisionless scrape-off layer during the disruption. The equation of motion of the MPs is solved inside the inhomogeneous vapor-cloud conditions. For a well-confined vapor cloud, the flight time of MPs in the vapor is short, and complete vaporization of the emitted MPs occurs. This will result in further reduction of net radiation power to the surface, i.e., 'droplet shielding' effect, However, if the vapor cloud has a high velocity component along the divertor surface, the MPs are quickly removed from the hot vapor region. A shorter flight time of the MPs in the vapor cloud call result in significant mass losses and extremely short erosion lifetime of the divertor surface and nearby components. (C) 2001 Elsevier Science B,V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Troitsk Inst Innovat & Fus Res, Moscow, Moscow Region, Russia. RP Hassanein, A (reprint author), Argonne Natl Lab, 9700 S Cass Ave,Bldg 362, Argonne, IL 60439 USA. NR 5 TC 15 Z9 15 U1 3 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 1074 EP 1078 DI 10.1016/S0022-3115(00)00665-6 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700214 ER PT J AU Hassanein, A Konkashbaev, I Nikandrov, L AF Hassanein, A Konkashbaev, I Nikandrov, L TI Heat and particle fluxes from collisionless scrape-off-layer during tokamak plasma disruptions SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE scrape-off layer; disruption; low recycling; heat flux; divertor material; HEIGHTS package ID DIVERTOR; MODEL AB The structure of collisionless scrape-off-layer (SOL) plasma in tokamak reactors is being studied to define the electron distribution function and the corresponding sheath potential between the divertor plate and the edge plasma. One feature of the collisionless SOL plasma is that the edge plasma acts as an electrostatic trap for electrons because electrons that originally have parallel energy lower than the wall potential will be trapped between the inner and outer divertor plates. Trapped electrons are very important in collisionless SOL plasma and are mainly responsible for charge neutralization of ions. Therefore, a full solution of the kinetic equation of particle transport to determine various electron fluxes is required. In this study, the dynamics of the SOL plasma during disruption was investigated with a 2-D numerical model that solves the kinetic Fokker-Planck equation for electron distribution. The main component of the electric potential exists within a region where the SOL ions are absorbed, i.e., at the front of the expanding vapor cloud. (C) 2001 Published by Elsevier Science B.V. C1 Argonne Natl Lab, Argonne, IL 60439 USA. TRINITI, Troitsk Inst Innovat & Fus Res, Troitsk 142092, Moscow Region, Russia. RP Hassanein, A (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 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 MAR PY 2001 VL 290 BP 1079 EP 1083 DI 10.1016/S0022-3115(00)00667-X PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700215 ER PT J AU Lasnier, CJ Leonard, AW Petrie, TW Watkins, JG AF Lasnier, CJ Leonard, AW Petrie, TW Watkins, JG TI Effect of magnetic geometry on ELM heat flux profiles SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE ELM; heat flux; divertor; thermography ID DIII-D AB In this paper, we explore how precisely the magnetic up/down symmetry must be controlled to insure sharing of edge localized mode (ELM) heat flux between upper and lower diverters in a double-null tokamak. We show for DIII-D, using infrared thermography, that the spatial distribution of Type-I ELM energy is less strongly affected by variations in magnetic geometry than the time-averaged peak heat flux in attached discharges. The degree of control necessary to share ELM heat Aux deposition equally between diverters was less stringent than the control needed to balance the time-averaged heat flux. ELM energy is transported more than four times further into the scrape-off layer (SOL) than the time-averaged heat flux. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Gen Atom Co, San Diego, CA 92186 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Lasnier, CJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 6 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 MAR PY 2001 VL 290 BP 1093 EP 1096 DI 10.1016/S0022-3115(00)00502-X PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700218 ER PT J AU Leonard, AW Osborne, TH Fenstermacher, ME Lasnier, CJ Mahdavi, MA AF Leonard, AW Osborne, TH Fenstermacher, ME Lasnier, CJ Mahdavi, MA TI Tolerable ELMs at high density in DIII-D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE DIII-D; ELM; power deposition; plasma edge AB The energy released at each edge-localized mode (ELM) is found to decrease in relation to the pedestal pressure, by more than a factor of five, as the line-averaged density in DIII-D H-mode is raised from about half the Greenwald density limit to near the Greenwald limit. The pedestal pressure remains nearly constant over this range demonstrating an attractive regime for future larger tokamaks. The reduction in ELM energy, in both low and high triangularity configurations, is seen to scale more with the pedestal electron temperature than the pedestal density. At low density both the electron density and temperature inside the separatrix drop due to the ELM instability; however at high density the density perturbation remains similar while the temperature profile is unaffected. ELMs at high density are also characterized by smaller magnetic fluctuations consistent with a higher toroidal mode number ELM instability. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Gen Atom Co, San Diego, CA 92186 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Leonard, AW (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 11 TC 19 Z9 19 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 1097 EP 1101 DI 10.1016/S0022-3115(00)00503-1 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700219 ER PT J AU Makhankov, A Barabash, V Mazul, I Youchison, D AF Makhankov, A Barabash, V Mazul, I Youchison, D TI Performance of the different tungsten grades under fusion relevant power loads SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE tungsten; thermal load AB The test results of several W grades at conditions typical for plasma facing component operations are summarised. These include the effects of steady-state heat fluxes (up to 43 MW/m(2)), disruption simulation (up to 30 MJ/m(2) during 0.05-0.36 ms) and heat Aux tests of W after disruption simulation. Representatives of the main W grades have been investigated: pure sintered W, W-Re and W-Mo cast alloys, W-1% La2O3, W-2% CeO2, single crystal W: etc. The resistance to high heat fluxes strongly depends on the orientation of the W grains to incident heat flux and with proper orientation W can withstand heat fluxes up to 27 MW/m(2). After disruption simulation, intensive surface crack formation has been observed for all studied W grades except single crystal W. Severe damage after disruption and thermal fatigue loading have been observed for almost all W grades except the W-5Re-0.1ZrC alloy and W-Re single crystal. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Efremov Inst Electrophys Apparatus, St Petersburg 189631, Russia. ITER, Joint Cent Team, D-85748 Garching, Germany. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Makhankov, A (reprint author), Efremov Inst Electrophys Apparatus, St Petersburg 189631, Russia. OI Youchison, Dennis/0000-0002-7366-1710 NR 5 TC 21 Z9 22 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 1117 EP 1122 DI 10.1016/S0022-3115(00)00668-1 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700223 ER PT J AU Naujoks, D Brooks, JN AF Naujoks, D Brooks, JN TI Combined sheath and thermal analysis of overheated surfaces in fusion devices SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE erosion; redeposition; plasma sheath; plasma facing materials ID LIMITERS AB The phenomenon of runaway surfaces overheating in fusion experiments due to plasma-sheath/surface-emission coupling has been analyzed. A semi-analytic model has been used as well as the BPHI-3D kinetic sheath code (J.N. Brooks, D, Naujoks, Phys. Plasmas 7 (2000) 2565) coupled with the THERM code which solves the non-stationary heat conduction equation also in 3D geometry. Runaway heating due to initial overheating and subsequent sheath breakdown and superheat has been analyzed for two materials - lithium and carbon. For typical liquid lithium divertor conditions the critical exposure time for thermal runaway is of order 10 ms - generally greater than plasma transient periods (e.g., ELMS) or flowing liquid exposure times. Critical exposure times for carbon are much longer (similar to1-2 s), as expected due to thermal property differences, and this may explain various 'hot spot' formations in carbon systems. It is also shown that, especially for carbon materials, effects such as flake formation and deterioration of heat conductivity can play a crucial role. (C) 2001 Elsevier Science B.V. All rights reserved. C1 EURATOM Assoc, Max Planck Inst Plasmaphys, D-10117 Berlin, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. RP Naujoks, D (reprint author), EURATOM Assoc, Max Planck Inst Plasmaphys, Mohrenstr 40-41, D-10117 Berlin, Germany. NR 4 TC 9 Z9 9 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 1123 EP 1127 DI 10.1016/S0022-3115(00)00549-3 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700224 ER PT J AU Sharpe, JP Merrill, BJ Petti, DA Bourham, MA Gilligan, JG AF Sharpe, JP Merrill, BJ Petti, DA Bourham, MA Gilligan, JG TI Modeling of particulate production in the SIRENS plasma disruption simulator SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE disruption; modelling ID DUST AB Modeling of the complex interplay among plasma physics, fluid mechanics, and aerosol dynamics is critical to providing a detailed understanding of the mechanisms responsible for particulate production from plasma-surface interaction in fusion devices. Plasma/fluid and aerosol models developed for analysis of disruption simulation experiments in the SIRENS high heat flux facility integrate the necessary mechanisms of plasma-material interaction, plasma and fluid flow, and particulate generation and transport. The model successfully predicts the size distribution of primary particulate generated in SIRENS disruption-induced material mobilization experiments, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID 83415 USA. N Carolina State Univ, Dept Nucl Engn, Raleigh, NC 27695 USA. RP Sharpe, JP (reprint author), Idaho Natl Engn & Environm Lab, Fus Safety Program, POB 1625,Ms 3860, Idaho Falls, ID 83415 USA. NR 15 TC 17 Z9 17 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 1128 EP 1133 DI 10.1016/S0022-3115(00)00550-X PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700225 ER PT J AU Buchenauer, DA Mills, BE Wood, R Woodruff, S Hill, DN Hooper, EB Cowgill, DF Clift, MW Yang, NY AF Buchenauer, DA Mills, BE Wood, R Woodruff, S Hill, DN Hooper, EB Cowgill, DF Clift, MW Yang, NY TI Characterization and conditioning of SSPX plasma facing surfaces SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE plasma-surface interaction; tungsten; conditioning ID DEPOSITION AB The Sustained Spheromak Physics Experiment (SSPX) will examine the confinement properties of spheromak plasmas sustained by DC helicity injection. Understanding the plasma-surface interactions is an important component of the experimental program since the spheromak plasma is in close contact with a stabilizing wall (flux conserver) and is maintained by a high current discharge in the coaxial injector region. Peak electron temperatures in the range of 400 eV are expected, so the copper plasma facing surfaces in SSPX have been coated with tungsten to minimize sputtering and plasma contamination, Here, we report on the characterization and conditioning of these surfaces used for the initial studies of spheromak formation in SSPX. The high pressure plasma-sprayed tungsten facing the SSPX plasma was characterized in situ using beta -backscattering and ex situ using laboratory measurements on similarly prepared samples. Measurements showed that water can be desorbed effectively through baking while the removal rates of volatile impurity gases during glow discharge and shot conditioning indicated a large source of carbon and oxygen in the porous coating. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Livermore, CA USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Buchenauer, DA (reprint author), Sandia Natl Labs, MS-9042,POB 969, Livermore, CA USA. NR 11 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 290 BP 1165 EP 1170 DI 10.1016/S0022-3115(00)00669-3 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700232 ER PT J AU Kugel, HW Maingi, R Wampler, W Barry, RE Bell, M Blanchard, W Gates, D Johnson, D Kaita, R Kaye, S Maqueda, R Menard, J Menon, MM Mueller, D Ono, M Paul, S Peng, YKM Raman, R Roquemore, A Skinner, CH Sabbagh, S Stratton, B Stutman, D Wilson, JR Zweben, S AF Kugel, HW Maingi, R Wampler, W Barry, RE Bell, M Blanchard, W Gates, D Johnson, D Kaita, R Kaye, S Maqueda, R Menard, J Menon, MM Mueller, D Ono, M Paul, S Peng, YKM Raman, R Roquemore, A Skinner, CH Sabbagh, S Stratton, B Stutman, D Wilson, JR Zweben, S CA NSTX Natl Res Team TI Overview of impurity control and wall conditioning in NSTX SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 14th International Conference on Plasma-Surface Interactions in Conrtrolled Fusion Devices CY MAY 22-26, 2000 CL ROSENHEIM, GERMANY DE wall conditioning; impurity control; glow discharge cleaning AB The national spherical torus experiment (NSTX) started plasma operations in February 1999. In the first extended period of experiments, NSTX achieved high current, inner wall limited, double null, and single null plasma discharges, initial Coaxial Helicity Injection, and high harmonic fast wave results. As expected, discharge reproducibility and performance were strongly affected by wall conditions. In this paper, we describe the internal geometry, and initial plasma discharge, impurity control, wail conditioning, erosion, and deposition results. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Washington, Seattle, WA 98195 USA. Columbia Univ, New York, NY 10027 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Sandia Natl Labs, Albuquerque, NM 87123 USA. RP Kugel, HW (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Sabbagh, Steven/C-7142-2011; Stutman, Dan/P-4048-2015; OI Menard, Jonathan/0000-0003-1292-3286 NR 11 TC 14 Z9 14 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 MAR PY 2001 VL 290 BP 1185 EP 1189 DI 10.1016/S0022-3115(00)00496-7 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 414QB UT WOS:000167676700236 ER PT J AU Zhang, Y Hart, KP Bourcier, WL Day, RA Colella, M Thomas, B Aly, Z Jostsons, A AF Zhang, Y Hart, KP Bourcier, WL Day, RA Colella, M Thomas, B Aly, Z Jostsons, A TI Kinetics of uranium release from Synroc phases SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID PYROCHLORE GROUP MINERALS; ZIRCONOLITE-RICH SYNROC; GEOCHEMICAL ALTERATION; DEPENDENCE; PLUTONIUM; SUBGROUP; WASTES; OXIDE; PH AB This paper presents experimental studies on the kinetics of U release from near single-phase zirconolite, pyrochlore, brannerite and pyrochlore-rich titanate ceramic materials. The dissolution tests were conducted at 20-75 degreesC with initial pHs from 2 to 12 and flow rates from 10 to 80 mi d(-1) in the open atmosphere. The U releases from these titanate materials are controlled by initial fast process and then followed by linear kinetics. The close-to-stoichiometric U release from zirconolite and pyrochlore-rich materials and preferential U release from brannerite are consistent with the alterations observed for the natural samples. The rate constants for U releases were determined and the effects of pH and temperature were examined. For each material, the U release vs. pH exhibits a V-shape with a minimum near pH 8. The measured activation energies suggest surface reaction controlled dissolution mechanism. Pyrochlore-rich materials and zirconolite demonstrated higher chemical durability and more resistance to aqueous attack than brannerite. However, impurities and minor brannerite inclusions do not appear to have a detrimental effect on U releases from pyrochlor-erich multi-phase ceramics. (C) 2001 Elsevier Science B.V. Ail rights reserved. C1 Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Zhang, Y (reprint author), Australian Nucl Sci & Technol Org, Private Mail Bag 1, Menai, NSW 2234, Australia. NR 22 TC 32 Z9 36 U1 0 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2001 VL 289 IS 3 BP 254 EP 262 DI 10.1016/S0022-3115(01)00423-8 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 419GL UT WOS:000167940900005 ER PT J AU Burr, T Stanbro, WD Charlton, W AF Burr, T Stanbro, WD Charlton, W TI An evaluation of safeguards approaches for neptunium SO JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY LA English DT Article DE systems analysis; alternate nuclear material; flow sheet verification; material balance accounting; neptunium; safeguards; evaluations AB The International Atomic Energy Agency has recently drawn attention to the fact that neptunium (Np), a byproduct of the nuclear power industry, can be used to make nuclear weapons. Current monitoring approaches for Np do not rely on material balance accounting as is used for uranium and plutonium. In the future this may change. Although full material balance accounting is not anticipated for Np, it is informative to evaluate the impact and benefit of full material balance accounting when considering other options. Therefore, this paper will apply systems analysis to evaluate ways to convert the current system to full materials balance accounting that will minimize the intrusiveness of the verification system and minimize costs to both the facility operator and the inspection agency. We then compare full material balance accounting to partial material balance accounting and to a ratio-monitoring technique referred to as flow sheet verification. We conclude that sampling approximately 25% of the batches is likely to be adequate and that Pu (or perhaps Cs-137) will be the most effective surrogate for estimating the Np in the input accountability tank. C1 Los Alamos Natl Lab, Safeguards Syst Grp, Los Alamos, NM 87545 USA. Univ Texas, Dept Mech Engn, Austin, TX 78712 USA. RP Los Alamos Natl Lab, Safeguards Syst Grp, Mail Stop E541, Los Alamos, NM 87545 USA. EM tburr@lanl.gov NR 16 TC 2 Z9 2 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0022-3131 EI 1881-1248 J9 J NUCL SCI TECHNOL JI J. Nucl. Sci. Technol. PD MAR PY 2001 VL 38 IS 3 BP 209 EP 216 DI 10.1080/18811248.2001.9715023 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 432EV UT WOS:000168680000006 ER PT J AU Chen, JB Angelici, RJ AF Chen, JB Angelici, RJ TI Reactions of Cp*Ir(2,5-dimethylthiophene) with electrophiles, acids, and maleic anhydride SO JOURNAL OF ORGANOMETALLIC CHEMISTRY LA English DT Article DE iridium complexes; hydrodesulfurization; maleic anhydride; thiophene; pentamethylcyclopentadienyl ID SULFUR BOND-CLEAVAGE; THIOPHENE COORDINATION; COMPLEXES; LIGANDS; REACTIVITY AB This paper describes reactions of the two isomers (eta Cp5-*)Ir(eta (4)-2,5-Me2T) (1) and (eta (5)-Cp*)Ir(C.S-2,5-Me2T) (2), where 2,5-Me2T is 2,5-dimethylthiophene, with several electrophiles, acids, and maleic anhydride. The reactions of 1 and 2 with methyl iodide give the same product Cp*Ir(eta (4)-2,5-Me2T . CH3)(+) in which the CH3+ is bonded to the sulfur atom, as established by X-ray studies. The reaction of 1 with maleic anhydride gives two structurally characterized products: Cp*Ir[eta (1) (S)-Cp*Ir(eta (4)-2,5-Me2T)][eta (2)-C4H2O3] (13). in which S-coordinated Cp*Ir(eta (4)-2,5-Me2T) and eta (2)-maleic anhydride are ligands to the Cp*Ir unit, and another product (12) that has the composition of 13 except for one additional oxygen atom. Complex 12, with a complicated and unusual structure, is also isolated from the reaction of maleic anhydride and the acylthiolate Cp*Ir[eta (4)-C3H2MeC(=O)Me] (14). Reactions of 1 and 2 with a variety of other agents (MeS-SMe2+, CF3SO3H, HCl, H2S. EtOH and I-2) are also described. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Chinese Acad Sci, Shanghai Inst Organ Chem, Shanghai 200032, Peoples R China. RP Angelici, RJ (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 23 TC 4 Z9 4 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-328X J9 J ORGANOMET CHEM JI J. Organomet. Chem. PD MAR 1 PY 2001 VL 621 IS 1-2 BP 55 EP 65 DI 10.1016/S0022-328X(00)00752-X PG 11 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 414AR UT WOS:000167644200008 ER PT J AU Zhan, CG Landry, DW AF Zhan, CG Landry, DW TI Theoretical studies of competing reaction pathways and energy barriers for alkaline ester hydrolysis of cocaine SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID CARBOXYLIC-ACID ESTERS; REACTION FIELD-THEORY; ISOTOPIC OXYGEN EXCHANGE; TRANSITION-STATE ANALOG; CATALYTIC ANTIBODIES; MOLECULAR-INTERACTIONS; CONCERTED MECHANISM; VOLUME POLARIZATION; ELECTRON-DENSITY; HYDROGEN-BOND AB Reaction pathways, solvent effects, and energy barriers have been determined for the base-catalyzed hydrolysis of the benzoyl-ester and methyl-ester groups of neutral cocaine and three smaller alkyl esters in aqueous solution by performing a series of ab initio molecular orbital and density functional theory calculations. The reaction coordinate calculations indicate that both the benzoyl-ester hydrolysis and the methyl-ester hydrolysis occur through a two-step process known for the majority of alkyl esters, i.e,, the formation of a tetrahedral intermediate by the attack of hydroxide oxygen at the carbonyl carbon (first step) followed by the decomposition of the tetrahedral intermediate to products (second step). This is the first first-principles study of the whole reaction pathway for cocaine benzoyl- and methyl-ester hydrolyses. The decomposition of the tetrahedral intermediate requires a proton transfer from the hydroxide/hydroxyl oxygen to the ester oxygen, as the C-O bond between carbonyl carbon and ester oxygen gradually breaks. We have examined two competing pathways for the second step of cocaine hydrolysis: one associated with the direct proton transfer from the hydroxide/hydroxyl oxygen to the ester oxygen, and the other associated with a water-assisted proton transfer. The energy barriers calculated for the second step of the benzoyl- and methyl-ester hydrolyses with water-assisted proton transfer are lower than the first step, whereas with direct proton transfer the barrier for the second step is higher. The first step should be rate-determining for the hydrolysis of both esters in aqueous solution, thus providing theoretical support to the design of the analogues of the first transition state that elicited anti-cocaine catalytic antibodies. The energy barrier, 7.6 kcal/mol, calculated for the first step of benzoyl-ester hydrolysis through the hydroxide attack from the Re face of the carbonyl is similar to1 kcal/mol lower than that through the hydroxide attack from the Si face. The energy barrier, 7.0 kcal/mol, calculated for the first step of cocaine methyl-ester hydrolysis is slightly lower than that of the benzoyl-ester. The effect of substituents on this energy barrier suggests that the transition state is significantly stabilized by hydrogen bonding between the hydroxide oxygen and the beta hydrogen for the carboxylic acid or alcohol moiety. C1 Columbia Univ, Coll Phys & Surg, Dept Med, New York, NY 10032 USA. RP Zhan, CG (reprint author), Pacific NW Natl Lab, Mailstop K1-83,Battelle Blvd,POB 999, Richland, WA 99352 USA. EM Chang-Guo.Zhan@pnl.gov NR 57 TC 47 Z9 49 U1 1 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD MAR 1 PY 2001 VL 105 IS 8 BP 1296 EP 1301 DI 10.1021/jp0023157 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 407JK UT WOS:000167268300012 ER PT J AU Werst, DW Vinokur, EI AF Werst, DW Vinokur, EI TI Radiation damage of alkoxy and siloxy ligands bonded to silica SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; ELECTRON-SPIN-RESONANCE; ALKANE RADICAL CATIONS; X-RAY; SEMICONDUCTOR NANOCRYSTALS; SURFACE; LITHOGRAPHY; REACTIVITY; CHEMISTRY; RESISTS AB The pattern of radiation-induced bond dissociation in alkoxy and siloxy ligands bonded to silica was studied using EPR spectroscopy. Bond-specific damage to ligands was deduced from observation of grafted and physisorbed radicals. Our results show that ligand damage predominates over desorption of ligands from the surface and are consistent with studies of radiation-induced modification of self-assembled monolayers on various types of substrates. Dissociation of C-H bonds is the dominant process, followed by C-C dissociation. In siloxy ligands losses of hydrogen atoms and alkyl groups were both major processes. Direct excitation of dissociative excited states of the organic ligands and ionization are both important damage mechanisms. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Werst, DW (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 51 TC 7 Z9 7 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAR 1 PY 2001 VL 105 IS 8 BP 1587 EP 1593 DI 10.1021/jp003806u PG 7 WC Chemistry, Physical SC Chemistry GA 407JC UT WOS:000167267600013 ER PT J AU Scholes, GD Jordanides, XJ Fleming, GR AF Scholes, GD Jordanides, XJ Fleming, GR TI Adapting the Forster theory of energy transfer for modeling dynamics in aggregated molecular assemblies SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID LIGHT-HARVESTING ARRAYS; EXCITON MIGRATION; PURPLE BACTERIA; ANTENNA SYSTEM; EXCITATION; STATES; MECHANISM; COMPLEXES; PIGMENTS; CRYSTAL AB The remarkable efficiencies of solar energy conversion attained by photosynthetic organisms derive partly from the designs of the light-harvesting apparatuses. The strategy employed by nature is to capture sunlight over a wide spectral and spatial cross section in chromophore arrays, then funnel the energy to a trap (reaction center). Nature's blueprint has inspired the conception of a diversity of artificial light-harvesting antenna systems for applications in solar energy conversion or photonics. Despite numerous, wide-ranging studies, truly quantitative predictions for such multichromophoric assemblies are scarce because Forster theory in its standard form often seems to fail. We report here a new framework within which energy transfer in molecular assemblies can be modeled quantitatively using a generalization of Forster's theory. Our results show that the principles involved in optimization of energy transfer in confined molecular assemblies are not revealed in a simple way by the absorption and emission spectra because such spectra are insensitive to length scales on the order of molecular dimensions. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Fleming, GR (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 57 TC 162 Z9 165 U1 0 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAR 1 PY 2001 VL 105 IS 8 BP 1640 EP 1651 DI 10.1021/jp003571m PG 12 WC Chemistry, Physical SC Chemistry GA 407JC UT WOS:000167267600019 ER PT J AU Jordanides, XJ Scholes, GD Fleming, GR AF Jordanides, XJ Scholes, GD Fleming, GR TI The mechanism of energy transfer in the bacterial photosynthetic reaction center SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Review ID RESONANCE RAMAN-SPECTRA; PRIMARY ELECTRON-DONOR; TEMPERATURE OPTICAL-TRANSITIONS; PHOTON-ECHO MEASUREMENTS; HOLE-BURNED SPECTRA; RHODOBACTER-SPHAEROIDES; RHODOPSEUDOMONAS-VIRIDIS; CHARGE SEPARATION; EXCITED-STATE; ACCESSORY BACTERIOCHLOROPHYLLS AB In the accompanying paper (Scholes, G. D.; Jordanides, X. J.; Fleming, G. R. J. Phys. Chem. 2001, 105, 1640), a generalization of Forster theory is developed to calculate electronic energy transfer (EET) in molecular aggregates. Here we apply the theory to wild-type and mutant photosynthetic reaction centers (RCs) from Rb. sphaeroides, as well as to the wild-type RC from Rps. viridis. Experimental information from the X-ray crystallographic structure, resonance Raman excitation profiles, and hole-burning measurements are integrated with calculated electronic couplings to model the EET dynamics within the RC complex. Optical absorption and circular dichroism spectra are calculated at various temperatures between 10 K and room temperature, and compare well with the experimentally observed spectra. The calculated rise time of the population of the lower exciton state of P, P-, as a result of energy transfer from the accessory bacteriochlorophyll, B, to the special pair, P, in Rb. sphaeroides (Rps. viridis) wild-type at 298 K is 193 fs (239 fs), and is in satisfactory agreement with experimental results. Our calculations, which employ a weak-coupling mechanism suggest that the upper exciton state of P, P+ plays a central role in trapping excitation from B. Our ability to predict the experimental rates is partly attributed to a proper calculation of the spectral overlap J(partial derivative alpha)(epsilon) using the vibronic progressions. The main advance we have made, however, is to calculate the electronic couplings V-partial derivative alpha in terms of the molecular composition of donor and/or acceptor aggregates, rather than treating the accepters P+ and P- as point dipoles associated with each spectroscopic band. Thus, we believe our electronic couplings capture the essence of the many-body interactions within the RC. Calculations for EET in two mutants, (M)L214H (the beta mutant) and (M)H202L (the heterodimer), are in reasonable agreement with experimental results. In the case of the heterodimer the agreement depends on a decrease in the electronic couplings between D-M and the rest of the pigments. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Fleming, GR (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 106 TC 89 Z9 92 U1 3 U2 17 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAR 1 PY 2001 VL 105 IS 8 BP 1652 EP 1669 DI 10.1021/jp003572e PG 18 WC Chemistry, Physical SC Chemistry GA 407JC UT WOS:000167267600020 ER PT J AU Odyniec, G AF Odyniec, G TI In the memory of Howel G Pugh SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Biographical-Item AB This fifth International Conference on Strangeness in Quark Matter is dedicated to the memory of Howel G Pugh. Howel G Pugh, a colleague of ours and former scientific director of the Bevalac, died of cancer in November of 1989. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Odyniec, G (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 0 TC 2 Z9 2 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 MAR PY 2001 VL 27 IS 3 BP 255 EP 256 DI 10.1088/0954-3899/27/3/301 PG 2 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200002 ER PT J AU Wang, FQ AF Wang, FQ TI Strangeness in dense nuclear matter: a review of AGS results SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; ANTIPROTON PRODUCTION; VACUUM EXCITATION; ENERGIES; MODEL AB Enhancement in strangeness production and the antihyperon to antibaryon ratio are two important signatures of quark-gluon plasma formation. Both signatures have been measured at the AGS. A review of these measurements is given. Implications of the measurements are discussed. C1 Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Wang, FQ (reprint author), Purdue Univ, Dept Phys, 1396 Phys, W Lafayette, IN 47907 USA. NR 28 TC 10 Z9 10 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 MAR PY 2001 VL 27 IS 3 BP 283 EP 292 DI 10.1088/0954-3899/27/3/305 PG 10 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200006 ER PT J AU Chung, P Alexander, JM Ajitanand, NN Anderson, M Best, D Brady, FP Case, T Caskey, W Cebra, D Chance, JL Cole, B Crowe, K Das, AC Draper, JE Gilkes, ML Gushue, S Heffner, M Hirsch, AS Hjort, EL Huo, L Justice, M Kaplan, M Keane, D Kintner, JC Klay, J Krofcheck, D Lacey, RA Law, C Lauret, J Lisa, MA Liu, H Liu, YM McGrath, R Milosevich, Z Odyniec, G Olson, DL Panitkin, S Pinkenburg, C Porile, NT Rai, G Ritter, HG Romero, JL Scharenberg, R Schroeder, L Srivastava, B Stone, NTB Symons, TJM Whitfield, J Witt, R Wood, L Zhang, WN AF Chung, P Alexander, JM Ajitanand, NN Anderson, M Best, D Brady, FP Case, T Caskey, W Cebra, D Chance, JL Cole, B Crowe, K Das, AC Draper, JE Gilkes, ML Gushue, S Heffner, M Hirsch, AS Hjort, EL Huo, L Justice, M Kaplan, M Keane, D Kintner, JC Klay, J Krofcheck, D Lacey, RA Law, C Lauret, J Lisa, MA Liu, H Liu, YM McGrath, R Milosevich, Z Odyniec, G Olson, DL Panitkin, S Pinkenburg, C Porile, NT Rai, G Ritter, HG Romero, JL Scharenberg, R Schroeder, L Srivastava, B Stone, NTB Symons, TJM Whitfield, J Witt, R Wood, L Zhang, WN TI Lambda flow and Lambda-P correlation in Au plus Au collisions at AGS energies SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID HEAVY-ION COLLISIONS; RELATIVISTIC NUCLEAR COLLISIONS; NEUTRON-STARS AB Transverse and radial how measurements are presented for A hyperons along with A-P correlations from Au + Au collisions at AGS energies. The flow measurements are compared with those of co-produced protons. The measurements indicate that A hyperons flow consistently in the same direction as protons but with a smaller magnitude for all beam energies. Comparisons with RQMD calculations show that the experimentally determined Lambda sideward flow is consistently larger compared with the calculated value obtained from scattering processes only. The experimental transverse flow ratio Lambda /P is consistent with predictions (similar or equal to (2)/(3)) of the quark counting rule at 2 A GeV but is found to decrease with increasing beam energy. These observations may be related to the detailed features of the A-nucleon potential for the nuclear densities produced. At 6 A GeV, np correlation functions are observed to be essentially flat (within statistical uncertainty), indicating little or no correlation between As and co-produced protons. This suggests that As may have a spacetime emission pattern which is different from that for protons. Further evidence from radial flow measurements also indicates that 6 A GeV A hyperons (at mid-rapidity) do not share the same emitting source characteristics as coproduced protons. C1 SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Columbia Univ, New York, NY 10027 USA. Ohio State Univ, Columbus, OH 43210 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Purdue Univ, W Lafayette, IN 47907 USA. Harbin Inst Technol, Harbin 150001, Peoples R China. Kent State Univ, Kent, OH 44242 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. St Marys Coll, Moraga, CA 94575 USA. Univ Auckland, Auckland 1, New Zealand. RP Chung, P (reprint author), SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. RI Witt, Richard/H-3560-2012 NR 15 TC 1 Z9 1 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAR PY 2001 VL 27 IS 3 BP 293 EP 299 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200007 ER PT J AU Back, BB AF Back, BB CA E917 Collaboration TI Strangeness production in Au plus Au collisions at AGS energies SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID ANTIPROTON PRODUCTION AB Collisions of Au + Au have been studied at beam kinetic energies of 6.0, 8.0 and 10.8 GeV/nucleon at the AGS facility at Brookhaven National Laboratory. Particles emitted from the collisions were momentum analysed and identified in a magnetic spectrometer. Proton rapidity distributions are compared with those expected for isotropic emission from a stopped source and it is concluded that there is a substantial amount of transparency at all three beam energies even for the most central collisions. Strangeness production were studied via measurements of K, phi and <()over bar> spectra. All three indicate a strong enhancement of strangeness production relative to pp-collisions at similar centre-of-mass energies. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Back, BB (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Holzman, Burt/0000-0001-5235-6314 NR 10 TC 3 Z9 3 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 MAR PY 2001 VL 27 IS 3 BP 301 EP 309 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200008 ER PT J AU Caines, H AF Caines, H CA E896 Collaboration TI An update on the strangeness production measurements and H-0 di-baryon search as performed by the AGS experiment 896 SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID H-DIBARYON; COLLISIONS AB E896 was designed to search for the predicted short-lived six-quark Ho dibaryon. The goal is to enhance the existing knowledge by extending the search into regions of shorter lifetimes (approximately half that of the lambda) and via exploring a new creation channel, that of the coalescence of two lambdas. Two main tracking chambers are used, a distributed drift chamber positioned to measure low-p, and high-rapidity neutral particle decay products and a silicon drift detector array which measures particle production at mid-rapidity. Both detectors are also investigating lambda polarization, over their respective coverages, for Au-Au collisions at 11.3 GeV/nucleon. The current status of the Ho di-baryon search and preliminary results of the strange particle production and polarization measurements will be presented. C1 Ohio State Univ, Columbus, OH 43210 USA. Univ Catania, I-95129 Catania, Italy. Wayne State Univ, Detroit, MI 48201 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Space Sci Lab, Berkeley, CA 94720 USA. Rice Univ, Houston, TX 77251 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Texas, Austin, TX 78712 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Yale Univ, New Haven, CT USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Caines, H (reprint author), Ohio State Univ, Columbus, OH 43210 USA. OI Tricomi, Alessia Rita/0000-0002-5071-5501; TUVE', Cristina/0000-0003-0739-3153 NR 17 TC 8 Z9 8 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAR PY 2001 VL 27 IS 3 BP 311 EP 318 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200009 ER PT J AU Schaffner-Bielich, J AF Schaffner-Bielich, J TI Effect of in-medium properties on heavy-ion collisions SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID HYPERNUCLEI; STRANGENESS; ENERGIES; NUCLEUS; DECAY AB The properties of strange hadrons, i.e. of kaons and hyperons, in the nuclear medium are discussed in connection with neutron star properties and relativistic heavy-ion collisions. Firstly, the relevant medium modifications of a kaon in a medium as provided by heavy-ion collisions is critically examined within a coupled-channel calculation. We demonstrate, that: particle ratios for kaons are not a sensitive probe of in-medium effects, while the K- flow is more suited to pinning down the K- optical potential in dense matter. Secondly, the interaction between hyperons is studied and may form bound states which can be produced in relativistic heavy-ion collisions. Signals for the detection of strange dibaryons by their decay topology and/or in the invariant mass spectra are outlined. C1 Brookhaven Natl Lab, RIKEN, BNL, Res Ctr, Upton, NY 11973 USA. RP Schaffner-Bielich, J (reprint author), Brookhaven Natl Lab, RIKEN, BNL, Res Ctr, Upton, NY 11973 USA. NR 25 TC 6 Z9 6 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAR PY 2001 VL 27 IS 3 BP 337 EP 347 DI 10.1088/0954-3899/27/3/311 PG 11 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200012 ER PT J AU Redlich, K Hamieh, S Tounsi, A AF Redlich, K Hamieh, S Tounsi, A TI Statistical hadronization and strangeness enhancement from p-A to Pb-Pb collisions SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID FREEZE-OUT PARAMETERS; HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; CANONICAL DESCRIPTION; CONSERVATION; PARTICLE; EQUILIBRATION; GEV/C; SPS AB The production of strange particles in Pb-Pb and p-A collisions at the SPS energy is discussed in the context of a statistical hadronization model. We show that the observed enhancement of strange baryon and antibaryon yields in Pb-Pb relative to p-Be and p-Pb collisions reported by the WA97 experiment can be quantitatively described in terms of the model if strangeness conservation is formulated in a canonical ensemble. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Wroclaw, Inst Theoret Phys, PL-50204 Wroclaw, Poland. Univ Paris 07, Phys Theor & Hautes Energies Lab, F-75251 Paris, France. RP Redlich, K (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 35 TC 10 Z9 10 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 MAR PY 2001 VL 27 IS 3 BP 413 EP 420 DI 10.1088/0954-3899/27/3/320 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200021 ER PT J AU Bravina, LV Zabrodin, EE Bleicher, M Bass, SA Brandstetter, M Faessler, A Fuchs, C Greiner, W Gorenstein, MI Soff, S Stocker, H AF Bravina, LV Zabrodin, EE Bleicher, M Bass, SA Brandstetter, M Faessler, A Fuchs, C Greiner, W Gorenstein, MI Soff, S Stocker, H TI Transition to resonance-rich matter in heavy-ion collisions at RHIC energies SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID QUANTUM MOLECULAR-DYNAMICS; FREEZE-OUT PARAMETERS; PLUS PB COLLISIONS; ART. NO. 024904; CHEMICAL EQUILIBRATION; NUCLEAR COLLISIONS; HADRONIC MATTER; 200A GEV; MODEL; NONEQUILIBRIUM AB The equilibration of hot and dense nuclear matter produced in the central region in central Au + Au collisions at roots = 200 A GeV is studied within the microscopic transport model UrQMD. The pressure here becomes isotropic at t approximate to 5 fm c(-1). Within the next 15 fm c(-1) the expansion of the matter proceeds almost isentropically with the entropy per baryon ratio S/A approximate to 150. During this period the equation of state in the (P, epsilon)-plane has a very simple form, P = 0.15 epsilon. Comparison with the statistical model (SM) of an ideal hadron gas reveals that the time of approximate to 20 fm c(-1) may be too short to attain the fully gas equilibrated state. In particular, the fractions of resonances are overpopulated in contrast with the SM values. The creation of such a long-lived resonance-rich stale slows down the relaxation to chemical equilibrium and can be detected experimentally. C1 Univ Tubingen, Inst Theoret Phys, D-7400 Tubingen, Germany. Moscow State Univ, Inst Phys Nucl, Moscow, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Univ Frankfurt, Inst Theoret Phys, D-6000 Frankfurt, Germany. Bogolyubov Inst Theoret Phys, Kiev, Ukraine. Gesell Schwerionenforsch, Darmstadt, Germany. RP Bravina, LV (reprint author), Univ Tubingen, Inst Theoret Phys, Morgenstelle 14, D-7400 Tubingen, Germany. RI Bleicher, Marcus/A-2758-2010; Stoecker, Horst/D-6173-2013; OI Stoecker, Horst/0000-0002-3282-3664; Bass, Steffen/0000-0002-9451-0954 NR 27 TC 7 Z9 7 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAR PY 2001 VL 27 IS 3 BP 421 EP 426 DI 10.1088/0954-3899/27/3/321 PG 6 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200022 ER PT J AU Soff, S Zschiesche, D Bleicher, M Hartnack, C Belkacem, M Bravina, L Zabrodin, E Bass, SA Stocker, H Greiner, W AF Soff, S Zschiesche, D Bleicher, M Hartnack, C Belkacem, M Bravina, L Zabrodin, E Bass, SA Stocker, H Greiner, W TI Enhanced strange particle yields - signal of a phase of massless particles? SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID HEAVY-ION COLLISIONS; PB-PB COLLISIONS; DYNAMICS; NUCLEON; PARTON; MODEL AB The yields ol strange particles are calculated with the ultrarelativistic quantum molecular dynamics model for p, Pb(158 A GeV)Pb collisions and compared with experimental data. The yields are enhanced in central collisions compared with proton-induced or peripheral Pb + Pb collisions. The enhancement is due to secondary interactions. Nevertheless, only a reduction of the quark masses or equivalently an increase of the string tension provides an adequate description of the large observed enhancement factors (WA97 and NA49). Furthermore, the yields of unstable strange resonances such as the Lambda* or the phi are considerably affected by hadronic rescattering of the decay products. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Gesell Schwerionenforsch, D-64220 Darmstadt, Germany. JW Goethe Univ, Inst Theoret Phys, D-60054 Frankfurt, Germany. Ecole Mines, SUBATECH, F-44072 Nantes, France. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Univ Tubingen, Inst Theoret Phys, D-72076 Tubingen, Germany. Duke Univ, Dept Phys, Durham, NC 27708 USA. RP Soff, S (reprint author), Brookhaven Natl Lab, Dept Phys, POB 5000, Upton, NY 11973 USA. RI Bleicher, Marcus/A-2758-2010; Stoecker, Horst/D-6173-2013; OI Stoecker, Horst/0000-0002-3282-3664; Bass, Steffen/0000-0002-9451-0954 NR 37 TC 22 Z9 22 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 MAR PY 2001 VL 27 IS 3 BP 449 EP 457 DI 10.1088/0954-3899/27/3/324 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200025 ER PT J AU Kampfer, B Peshier, A Soff, G AF Kampfer, B Peshier, A Soff, G TI Strange quark matter: mapping QCD lattice results to finite baryon density using a quasi-particle model SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID GAUGE VECTOR-MESONS; THERMAL-LOOP RESUMMATION; GROUND-STATE ENERGY; GLUON PLASMA; MASSIVE GLUONS; FERMIONS; THERMODYNAMICS; TEMPERATURE; EQUATION; PRESSURE AB A quasi-particle model is presented which describes QCD lattice results for the zero-, two- and four-quark-flavour equation of state. The results are mapped to finite baryo-chemical potentials. As an application of the model we make a prediction of deconfined matter with appropriate inclusion of strange quarks and consider pure quark stars. C1 Rossendorf Inc, Forschungszentrum Rossendorf EV, D-01314 Dresden, Germany. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Tech Univ Dresden, Inst Theoret Phys, D-01062 Dresden, Germany. RP Kampfer, B (reprint author), Rossendorf Inc, Forschungszentrum Rossendorf EV, Postfach 510119, D-01314 Dresden, Germany. NR 36 TC 2 Z9 2 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 MAR PY 2001 VL 27 IS 3 BP 535 EP 540 DI 10.1088/0954-3899/27/3/334 PG 6 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200035 ER PT J AU Kaneta, M Xu, N AF Kaneta, M Xu, N TI On chemical equilibrium in high-energy heavy-ion collisions SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID NUCLEUS-NUCLEUS COLLISIONS; SPS AB The thermal fitting parameters depend on the phase space coverage. It is questionable to interpret the fitting results extracted from the experimental measured particle yields within finite phase space. We test this idea with the transport models RQMD and NEXUS for heavy-ion collisions at both SPS and RHIC energies. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Kaneta, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 15 TC 14 Z9 14 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 MAR PY 2001 VL 27 IS 3 BP 589 EP 592 DI 10.1088/0954-3899/27/3/342 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200045 ER PT J AU Vance, SE AF Vance, SE TI A microscopic picture of strangeness production at the SPS SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; BARYON NUMBER; PB COLLISIONS; MATTER; ENHANCEMENT; MODEL; HADRONIZATION; DYNAMICS AB The microscopic origin of the strangeness enhancements observed in PbPb collisions at the SPS is studied by testing the effects of three mechanisms. First, the junction processes found in the HIJING/B (B) over bar event generator are reviewed showing that they can account for only part of the observed hyperon enhancements. Second, the efficient final state chemical changing processes (e.g. Lambda + K <----> Xi + pi) are included by adding the General Cascade Program (GCP) to HIJING/B (B) over bar. While these processes are shown to further enhance multistrange baryon production, HIJING/B (B) over bar +GCP is still unable to fully describe either the large hyperon yields or the increasing K+/pi (+) ratio. Finally, the addition of transient field fluctuations or ropes to HIJING/B (B) over bar +GCP is shown to be needed to account for the large hyperon yields and for the behaviour of the K+/pi (+) ratio. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Brookhaven Natl Lab, Upton, NY 11973 USA. EM vance@bnl.gov NR 42 TC 11 Z9 11 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 EI 1361-6471 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAR PY 2001 VL 27 IS 3 BP 603 EP 610 DI 10.1088/0954-3899/27/3/344 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200047 ER PT J AU Jeon, S AF Jeon, S TI Event-by-event s/(s)over-bar fluctuations in a rapidity interval as a QGP signal SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID HEAVY-ION COLLISIONS AB We advocate multiplicity ratio fluctuations. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Jeon, S (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAR PY 2001 VL 27 IS 3 BP 611 EP 616 DI 10.1088/0954-3899/27/3/345 PG 6 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200048 ER PT J AU Jones, PG Jacobs, PM AF Jones, PG Jacobs, PM CA STAR Collaboration TI Overview of the status and strangeness capabilities of STAR SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS AB STAR is a large-acceptance spectrometer capable of precision measurements of a wide variety of strange particles. We discuss the STAR detector, its configuration during the first two years of RHIC operation, and its initial performance for Au + Au collisions. The expected performance for strangeness physics and initial data on strange particle reconstruction in Au + Au collisions are presented. C1 Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Jones, PG (reprint author), Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. NR 4 TC 1 Z9 1 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAR PY 2001 VL 27 IS 3 BP 651 EP 658 DI 10.1088/0954-3899/27/3/350 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200053 ER PT J AU Kharzeev, D AF Kharzeev, D TI Strangeness and charm at RHIC SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 5th International Conference on Strangeness in Quark Matter CY JUL 20-25, 2000 CL UNIV CALIF BERKEKEY, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF BERKEKEY, CLARK KERR CAMPUS ID QUARK-GLUON PLASMA; ANTIPROTON ANNIHILATION; BARYON NUMBER; SIGMA-TERM; PROTON; SPIN AB Strangeness and charm production will be the subject of intense experimental studies at RHIC. In this paper I discuss what is known at present about the strangeness and charm contents of the vacuum and light hadrons, and what can be expected in high-energy nuclear collisions. Some ideas for new measurements at RHIC are also presented. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, Res Ctr, RIKEN, Upton, NY 11973 USA. RP Kharzeev, D (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 42 TC 0 Z9 0 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 MAR PY 2001 VL 27 IS 3 BP 707 EP 713 DI 10.1088/0954-3899/27/3/358 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 413XQ UT WOS:000167637200061 ER PT J AU Shelnutt, JA AF Shelnutt, JA TI Normal-coordinate structural decomposition and the vibronic spectra of porphyrins SO JOURNAL OF PORPHYRINS AND PHTHALOCYANINES LA English DT Article DE non-planar porphyrins; ruffled porphyrins; heme; Raman spectroscopy; vibrational spectra; conformational distortion ID MACROCYCLE AB The connection is made between macrocycle deformations obtained from normal-coordinate structural decomposition (NSD) and the vibronic molecular states and spectra of porphyrins. NSD is a procedure that provides a description of the time-averaged distortion of a porphyrin in terms of normal-coordinate displacements from a D-4h symmetric reference structure. Expressions for the optical absorption spectra with vibrational structure are developed with these NSD-determined deformations as parameters. Using these expressions, the effects of macrocycle distortion on the UV-vis absorption spectra of porphyrins are determined. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Sandia Natl Labs, Biomol Mat & Interfaces Dept, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. RP Shelnutt, JA (reprint author), Sandia Natl Labs, Biomol Mat & Interfaces Dept, Albuquerque, NM 87131 USA. RI Shelnutt, John/A-9987-2009 OI Shelnutt, John/0000-0001-7368-582X NR 5 TC 10 Z9 10 U1 1 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1088-4246 J9 J PORPHYR PHTHALOCYA JI J. Porphyr. Phthalocyanines PD MAR PY 2001 VL 5 IS 3 BP 300 EP 311 DI 10.1002/jpp.320 PG 12 WC Chemistry, Multidisciplinary SC Chemistry GA 411EB UT WOS:000167484200009 ER PT J AU Stallard, BW Hooper, EB Power, JL AF Stallard, BW Hooper, EB Power, JL TI Plasma confinement in the whistler wave plasma thruster SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID ELECTRIC PROPULSION; RESONANCE AB Plasma thruster experiments using whistler wave plasma heating of electrons have shown large increases in the operating density and the plasma potential providing for ion acceleration when the edge potential was controlled through use of electrically floating electrodes at the plasma edge. Analysis of these results show that E x B (vector cross product) drifts within the radial electric field in the small diameter plasma column dominated the ion confinement and power balance. Measurements of a density increase at higher magnetic field are consistent with the predictions of ion orbit analysis. Device modifications to improve thruster performance are discussed. C1 Lawrence Livermore Natl Lab, Laser Directorate, Livermore, CA 94551 USA. NASA, John H Glenn Res Ctr Lewis Field, Board Propuls Branch, Cleveland, OH 44135 USA. RP Stallard, BW (reprint author), Lawrence Livermore Natl Lab, Laser Directorate, Box 808,L-637, Livermore, CA 94551 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 2001 VL 17 IS 2 BP 433 EP 440 DI 10.2514/2.5760 PG 8 WC Engineering, Aerospace SC Engineering GA 411TZ UT WOS:000167516500028 ER PT J AU Wilmarth, WR Rosencrance, SW Nash, CA DiPrete, DP DiPrete, CC AF Wilmarth, WR Rosencrance, SW Nash, CA DiPrete, DP DiPrete, CC TI Transuranium removal from Hanford High Level Waste simulants using sodium permanganate and calcium SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article ID MANGANESE; WATER AB Hanford High Level Waste will require processing to reduce the concentration of various actinide elements prior to encapsulation into low activity glass for disposition. High level waste at Hanford contains elevated actinide concentrations in the supernate because of organic complexants present in the tanks. Traditional removal strategies are not viable processing sequences for the Hanford tanks containing complexants. Reported here is a novel actinide decontamination strategy. This pretreatment sequence consists of addition of calcium nitrate and sodium permanganate The observed optimum decontamination efficiencies for plutonium and americium are more than 99.5%. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Wilmarth, WR (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. NR 14 TC 2 Z9 2 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAR PY 2001 VL 247 IS 3 BP 501 EP 506 DI 10.1023/A:1010657806633 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 415HQ UT WOS:000167715700004 ER PT J AU Silver, GL AF Silver, GL TI Pu(IV) polymer formation SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article AB Nearest-neighbor coagulation is proposed as a mechanism for Pu(IV) polymer formation. The distribution of colloids generated by this process is intuitive and easy to understand. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Silver, GL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS E502, Los Alamos, NM 87544 USA. NR 4 TC 4 Z9 4 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 MAR PY 2001 VL 247 IS 3 BP 561 EP 562 DI 10.1023/A:1010690728923 PG 2 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 415HQ UT WOS:000167715700016 ER PT J AU Elmroth, E Ding, C Wu, YS AF Elmroth, E Ding, C Wu, YS TI High performance computations for large scale simulations of subsurface multiphase fluid and heat flow SO JOURNAL OF SUPERCOMPUTING LA English DT Article DE groundwater flow; grid partitioning; iterative linear solvers; preconditioners; software design; performance analysis AB TOUGH2 is a widely used reservoir simulator for solving subsurface flow related problems such as nuclear waste geologic isolation, environmental remediation of soil and groundwater contamination, and geothermal reservoir engineering. It solves a set of coupled mass and energy balance equations using a finite volume method. This contribution presents the design and analysis of a parallel version of TOUGH2. The parallel implementation first partitions the unstructured computational domain. For each time step, a set of coupled non-linear equations is solved with Newton iteration. In each Newton step, a Jacobian matrix is calculated and an ill-conditioned non-symmetric linear system is solved using a preconditioned iterative solver. Communication is required for convergence tests and data exchange across partitioning borders. Parallel performance results on Cray T3E-900 are presented for two real application problems arising in the Yucca Mountain nuclear waste site study. The execution time is reduced from 7504 seconds on two processors to 126 seconds on 128 processors for a 2D problem involving 52,752 equations. For a larger 3D problem with 293,928 equations the time decreases from 10,055 seconds on 16 processors to 329 seconds on 512 processors. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Elmroth, E (reprint author), Umea Univ, Dept Comp Sci, SE-90187 Umea, Sweden. RI Wu, Yu-Shu/A-5800-2011 NR 14 TC 9 Z9 9 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0920-8542 J9 J SUPERCOMPUT JI J. Supercomput. PD MAR PY 2001 VL 18 IS 3 BP 235 EP 258 DI 10.1023/A:1008117130225 PG 24 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 417XG UT WOS:000167860300001 ER PT J AU He, Y Ding, CHQ AF He, Y Ding, CHQ TI Using accurate arithmetics to improve numerical reproducibility and stability in parallel applications SO JOURNAL OF SUPERCOMPUTING LA English DT Article DE reproducibility; climate models; double-double precision arithmetic; self-compensated summation; distributed memory architecture ID COMMUNITY CLIMATE MODEL; DESIGN AB Numerical reproducibility and stability of large scale scientific simulations, especially climate modeling, on distributed memory parallel computers are becoming critical issues. In particular, global summation of distributed arrays is most susceptible to rounding errors, and their propagation and accumulation cause uncertainty in final simulation results. We analyzed several accurate summation methods and found that two methods are particularly effective to improve (ensure) reproducibility and stability: Kahan's self-compensated summation and Bailey's double-double precision summation. We provide an MPI operator MPI_SUMDD to work with MPI collective operations to ensure a scalable implementation on large number of processors. The final methods are particularly simple to adopt in practical codes: not only global summations, but also vector-vector dot products and matrix-vector or matrix-matrix operations. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC Div, Berkeley, CA 94720 USA. RP He, Y (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC Div, Berkeley, CA 94720 USA. NR 26 TC 36 Z9 36 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0920-8542 J9 J SUPERCOMPUT JI J. Supercomput. PD MAR PY 2001 VL 18 IS 3 BP 259 EP 277 DI 10.1023/A:1008153532043 PG 19 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 417XG UT WOS:000167860300002 ER PT J AU Hasnain, SS Kamitsubo, H Mills, DM AF Hasnain, SS Kamitsubo, H Mills, DM TI XAFS XI and new sources in Europe - SLS, SOLEIL and DIAMOND SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Editorial Material C1 CLRC, Daresbury Lab, Dept Synchrotron Radiat, Warrington WA4 4AD, Cheshire, England. JASRI, Sayo, Hyogo 6785198, Japan. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Hasnain, SS (reprint author), CLRC, Daresbury Lab, Dept Synchrotron Radiat, Warrington WA4 4AD, Cheshire, England. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 47 EP 48 DI 10.1107/S0909049501001364 PN 2 PG 2 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100001 PM 11512818 ER PT J AU Scholl, A Nolting, F Stohr, J Luning, J Seo, JW Locquet, JP Fompeyrine, J Anders, S Ohldag, H Padmore, HA AF Scholl, A Nolting, F Stohr, J Luning, J Seo, JW Locquet, JP Fompeyrine, J Anders, S Ohldag, H Padmore, HA TI Studies of the magnetic structure at the ferromagnet-antiferromagnet interface SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE magnetic properties; ferromagnet-antiferromagnet interface; photoelectron emission microscopy (PEEM); X-ray magnetic dichroism; thin films ID THIN-FILMS; TEMPERATURE; DICHROISM; SPECTROSCOPY; MOMENTS; SURFACE AB Antiferromagnetic layers are a scientifically challenging component in magnetoelectronic devices, such as magnetic sensors in hard-disk heads, or magnetic random-access memory (RAM) elements. In this paper, it is shown that photoelectron emission microscopy (PEEM) is capable of determining the magnetic structure at the interface of ferromagnets and antiferromagnets with high spatial resolution (down to 20 nm). Dichroism effects at the L edges of the magnetic 3d transition metals, using circularly or linearly polarized soft X-rays from a synchrotron source, give rise to a magnetic image contrast. Images, acquired with the PEEM2 experiment at the Advanced Light Source, show magnetic contrast for antiferromagnetic LaFeO3, microscopically resolving the magnetic domain structure in an antiferromagnetically ordered thin film for the first time. Magnetic coupling between LaFeO3 and an adjacent Co layer results in a complete correlation of their magnetic domain structures. From field-dependent measurements, a unidirectional anisotropy resulting in a local exchange bias of up to 30 Oe in single domains could be deduced. The elemental specificity and the quantitative magnetic sensitivity render PEEM a perfect tool to study magnetic coupling effects in multilayered thin-film samples. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. IBM Corp, Almaden Res Ctr, Div Res, San Jose, CA 95120 USA. Univ Neuchatel, Inst Phys, CH-2000 Neuchatel, Switzerland. IBM Corp, Div Res, Zurich Res Lab, CH-8803 Ruschlikon, Switzerland. Univ Dusseldorf, Inst Appl Phys, D-40225 Dusseldorf, Germany. RP Scholl, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Seo, Jin Won/J-3980-2013; Scholl, Andreas/K-4876-2012; Ohldag, Hendrik/F-1009-2014; Raoux, Simone/G-3920-2016 OI Seo, Jin Won/0000-0003-4937-0769; NR 15 TC 1 Z9 1 U1 0 U2 16 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 101 EP 104 DI 10.1107/S0909049500016460 PN 2 PG 4 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100012 PM 11512704 ER PT J AU Arvanitis, D Dunn, JH Karis, O Hahlin, A Brena, B Carr, R Martensson, N AF Arvanitis, D Dunn, JH Karis, O Hahlin, A Brena, B Carr, R Martensson, N TI Magnetic X-ray circular dichroism on in situ grown 3d magnetic thin films on surfaces SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE epitaxic film; magnetic moment; transverse coherence; resonant reflectivity ID ABSORPTION SPECTROSCOPY; SOURCE COHERENCE; CO; CU(100) AB Epitaxic thin and ultrathin films on surfaces allow crystallographic phases that do not occur naturally in the bulk to be stabilized. They also offer new possibilities for an improved understanding of soft X-ray photoabsorption in magnetic systems. Data collected using the Elliptically Polarizing Undulator at BL 5.2 of the Stanford Synchrotron Radiation Laboratory are presented herein. Fe, Co and Ni films were prepared on Cu(100) surfaces. L-2,L-3-edge spectra were recorded with circular and linear light. Fresnel diffractometry was used to quantify the degree of transverse beam coherence. A quantitative analysis of the spectral features indicates a correlation of the spectral intensities and the transverse beam coherence. Resonant reflectivity spectra for Co ultrathin films that exhibit strong dichroism are presented. The reflectivity data indicate that interference effects of the reflected beams at the two interfaces are of importance, even for ultrathin films. C1 Uppsala Univ, Dept Phys, S-75121 Uppsala, Sweden. Stanford Univ, SLAC, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Arvanitis, D (reprint author), Uppsala Univ, Dept Phys, Box 530, S-75121 Uppsala, Sweden. RI Brena, Barbara/C-5909-2014; OI Karis, Olof/0000-0001-6406-217X NR 18 TC 3 Z9 3 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 120 EP 124 DI 10.1107/S0909049500019890 PN 2 PG 5 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100016 PM 11512708 ER PT J AU Haskel, D Stern, EA Dogan, F Moodenbaugh, AR AF Haskel, D Stern, EA Dogan, F Moodenbaugh, AR TI Dopant structural distortions in high-temperature superconductors: an active or a passive role? SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE high-temperature superconductors; dopants; lattice distortions ID ANISOTROPIC TRANSPORT; ELECTRONIC-STRUCTURE; PHASE-TRANSITIONS; DOPED HOLES; LA2-XSRXCUO4; LA2-XBAXCUO4; SCATTERING; XAFS AB The parent compounds of high-temperature superconductors, such as YBa2Cu3O6 and La2CuO4, are strongly interacting electron systems, rendering them insulators with Mott-Hubbard gaps of a few electronvolts. Charge carriers (holes) are introduced by chemical doping, causing an insulator-metal (IM) transition and, at low temperatures, superconductivity. The role of dopants is widely seen as limited to the introduction of holes into the CuO2 planes (i.e. occupying electronic states derived from Cu 3d(x2-y2) and O 2p(x,y) atomic orbitals). Most theories of high-Tc superconductivity deal with pairing interactions between these planar holes. Local distortions around dopants are poorly understood, because of the experimental difficulty in obtaining such information, particularly at low doping. This has resulted in the neglect, in most theories, of the effect of such distortions on the chemical and electronic structure of high-Tc superconductors. Angular-resolved X-ray absorption fine structure (XAFS) spectroscopy on oriented samples is an ideal technique to elucidate the dopant distortions. Element specificity, together with a large orientation dependence of the XAFS signal in these layered structures, allows the local structure around dopants to be resolved. Results are presented here on (Sr, Ba) and Ni dopants, which substitute at the La and Cu sites, respectively, of insulating La2CuO4. The relevance of the measured local distortions for a complete understanding of the normal and superconducting properties of cuprates is discussed. C1 Argonne Natl Lab, Adv Photon Source, Expt Facil Div, Argonne, IL 60439 USA. Univ Washington, Dept Phys, Seattle, WA 98195 USA. Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA. Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. RP Haskel, D (reprint author), Argonne Natl Lab, Adv Photon Source, Expt Facil Div, Argonne, IL 60439 USA. OI Moodenbaugh, Arnold/0000-0002-3415-6762 NR 23 TC 9 Z9 9 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 MAR PY 2001 VL 8 BP 186 EP 190 DI 10.1107/S090904950001846X PN 2 PG 5 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100030 PM 11512722 ER PT J AU Booth, CH Bauer, ED Maple, MB Lawrence, JM Kwei, GH Sarrao, JL AF Booth, CH Bauer, ED Maple, MB Lawrence, JM Kwei, GH Sarrao, JL TI Lattice disorder in strongly correlated lanthanide and actinide intermetallics SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE disordered materials; non-Fermi liquids; Kondo effect ID FERMI-LIQUID BEHAVIOR; ELECTRONIC-STRUCTURE; UCU5-XPDX; MODEL AB Lanthanide and actinide intermetallic compounds display a wide range of correlated-electron behavior, including ferromagnetism, antiferromagnetism, nonmagnetic (Kondo) ground states, and so-called 'non-Fermi liquid' (NFL) behavior. The interaction between f electrons and the conduction band is a dominant factor in determining the ground state of a given system. However, lattice disorder can create a distribution of interactions, generating unusual physical properties. These properties may include NFL behavior in many materials. In addition, lattice disorder can cause deviations from standard Kondo behavior that is less severe than NFL behavior. A review of the lattice disorder mechanism within a tight-binding model is presented, along with measurements of the YbBCu4 and UPdxCu5-x systems, demonstrating the applicability of the model. These measurements indicate that while the YbBCu4 system appears to be well ordered, both site interchange and continuous bond-length disorder occur in the UPdxCu5-x series. Nevertheless, the measured bond-length disorder in UPdCu4 does not appear to be enough to explain the NFL properties simply with the Kondo disorder model. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif San Diego, Inst Pure & Appl Phys, La Jolla, CA 92093 USA. Univ Calif Irvine, Dept Phys, Irvine, CA 92697 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Booth, CH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, Div Chem Sci, Berkeley, CA 94720 USA. EM chbooth@lbl.gov RI Bauer, Eric/D-7212-2011; Booth, Corwin/A-7877-2008 NR 16 TC 2 Z9 2 U1 1 U2 1 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0909-0495 EI 1600-5775 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 191 EP 195 DI 10.1107/S0909049500019026 PN 2 PG 5 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100031 PM 11512723 ER PT J AU Bergmann, U Glatzel, P Robblee, JH Messinger, J Fernandez, C Cinco, R Visser, H McFarlane, K Bellacchio, E Pizarro, S Sauer, K Yachandra, VK Klein, MP Cox, BL Nealson, KH Cramer, SP AF Bergmann, U Glatzel, P Robblee, JH Messinger, J Fernandez, C Cinco, R Visser, H McFarlane, K Bellacchio, E Pizarro, S Sauer, K Yachandra, VK Klein, MP Cox, BL Nealson, KH Cramer, SP TI High-resolution X-ray spectroscopy of rare events: a different look at local structure and chemistry SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE X-ray fluorescence spectroscopy; X-ray Raman scattering; inelastic scattering; high resolution; metalloproteins ID OXYGEN-EVOLVING COMPLEX; MANGANESE CLUSTER; FLUORESCENCE SPECTROSCOPY; RAMAN-SPECTROSCOPY; OXIDATION-STATES; PHOTOSYSTEM-II; SENSITIVITY; WATER; TRANSITIONS; DEPENDENCE AB The combination of large-acceptance high-resolution X-ray optics with bright synchrotron sources permits quantitative analysis of rare events such as X-ray fluorescence from very dilute systems, weak fluorescence transitions or X-ray Raman scattering. Transition-metal K beta fluorescence contains information about spin and oxidation state; examples of the characterization of the Mn oxidation states in the oxygen-evolving complex of photosystem II and Mn-consuming spores from the marine bacillus SG-1 are presented. Weaker features of the K beta spectrum resulting from valence-level and 'interatomic' ligand to metal transitions contain detailed information on the ligand-atom type, distance and orientation. Applications of this spectral region to characterize the local structure of model compounds are presented. X-ray Raman scattering (XRS) is an extremely rare event, but also represents a unique technique to obtain bulk-sensitive low-energy (<600 eV) X-ray absorption fine structure (XAFS) spectra using hard ( 10 keV) X-rays. A photon is inelastically scattered, losing part of its energy to promote an electron into an unoccupied level. In many cases, the cross section is proportional to that of the corresponding absorption process yielding the same X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) features. XRS finds application for systems that defy XAFS analysis at low energies, e.g. liquids or highly concentrated complex systems, reactive compounds and samples under extreme conditions (pressure, temperature). Recent results are discussed. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bergmann, U (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RI Fernandez, Carmen/C-9546-2012; Glatzel, Pieter/E-9958-2010; Institute of Chemistry - USP, Dept. of Chemistry/B-8988-2012 OI Fernandez, Carmen/0000-0003-2201-6241; Glatzel, Pieter/0000-0001-6532-8144; FU NIGMS NIH HHS [R56 GM055302, GM 55302, GM-48145, R01 GM055302] NR 39 TC 27 Z9 28 U1 1 U2 21 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 199 EP 203 DI 10.1107/S0909049500016484 PN 2 PG 5 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100033 PM 11512725 ER PT J AU Ito, Y Vlaicu, AM Shigeoka, N OhHashi, H Mutaguchi, K Nakata, Y Emura, S Grush, M Stolte, W Schlachter, F AF Ito, Y Vlaicu, AM Shigeoka, N OhHashi, H Mutaguchi, K Nakata, Y Emura, S Grush, M Stolte, W Schlachter, F TI Double electron transitions [MN] or [MO] above W-74 M-III edge in X-ray absorption spectra SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN ID K-EDGE; MULTIELECTRON TRANSITIONS; EXCITATION CHANNELS; FINE-STRUCTURE; PHOTOEXCITATION; RESONANCES; THRESHOLD; ELEMENTS; KRYPTON; ARGON AB The x-ray absorption spectra in metallic W (Tungsten) have been measured above M-III edge using the third generation synchrotron radiation, ALS, Berkeley. Several features caused by multi-electron transitions were detected on M-III in solid phase. [3p4f], [3p5s], and [3p5p] double electron transitions were identified by the Z+1 approximation. C1 Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Kyoto Univ, Inst Chem Res, Kyoto 6110011, Japan. Osaka Univ, Inst Sci & Ind Res, Fukushima 9708551, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Iwaki Meisei Univ, Coll Sci & Engn, Fukushima 9708551, Japan. RP Ito, Y (reprint author), Univ Tennessee, Dept Phys, 401 Nielson Phys Bldg, Knoxville, TN 37996 USA. NR 28 TC 0 Z9 0 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 249 EP 251 DI 10.1107/S0909049501000760 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100050 PM 11512742 ER PT J AU Conradson, S Espinosa, F Villella, P AF Conradson, S Espinosa, F Villella, P TI Local structure probes of nanoscale heterogeneity in crystalline materials SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE Nanoscale; heterogeneity; local structure; XAFS; PDF; pair distribution ID X-RAY-ABSORPTION; FILMS AB In the conventional model of condensed matter increasing numbers of defects break down the order and ultimately convert perfect periodic crystals into aperiodic glasses. Local structure probes of a variety of materials with non-stoichiometric compositions, multiple degenerate ordering modes, or other symmetry breaking factors identify multiple ordered arrangements of atoms that render the materials heterogeneous on the nanometer scale. While exerting apparently negligible effects on bulk properties, this heterogeneity or phase separation does influence correlated or collective properties such as magnetism and phase stability. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Conradson, S (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 273 EP 275 DI 10.1107/S0909049500018999 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100058 PM 11512750 ER PT J AU Kelly, SD Stern, EA Ingalls, R AF Kelly, SD Stern, EA Ingalls, R TI Determining crystalline atomic positions using XAFS, a new addition to the UWXAFS analysis package SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE crystal structure; atomic positions; high pressure temperature; UWXAFS AB XAFS and x-ray diffraction (XRD) are complementary structure determination techniques. The combination of XAFS and XRD can be used to determine the complete crystal structure when diffraction can not be refined. This is often the case at high pressures or high temperatures where there is limited access to the samples and energy dispersive x-ray diffraction is used. A new method to determine the atomic positions within the unit cell using EXAFS data with the programs RUNFIT and MKFIT is described. These programs systematically produce and test models for the XAFS data that are consistent with the diffraction results. The programs were written to solve the structure of two intermediate high pressure phases of AgCl, and are distributed with a working example. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. RP Kelly, SD (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 5 TC 2 Z9 2 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 311 EP 313 DI 10.1107/S0909049500016952 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100071 PM 11512763 ER PT J AU Fischer, P Eimuller, T Schutz, G Bayreuther, G Tsunashima, S Takagi, N Denbeaux, G Attwood, D AF Fischer, P Eimuller, T Schutz, G Bayreuther, G Tsunashima, S Takagi, N Denbeaux, G Attwood, D TI Magnetic domains in nanostructured media studied with M-TXM SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE X-ray magnetic circular dichroism; X-ray microscopy; magnetic domains ID RAY CIRCULAR-DICHROISM AB Combining X-ray magnetic circular dichroism (X-MCD) with a transmission X-ray microscope (TXM) allows to image element-specifically magnetic domain structures with 25nm lateral resolution. Both in-plane and out-of-plane systems can be studied in applied magnetic fields. Thus field-dependent parameters, as individual nucleation fields in magnetic nanostructures can be deduced and related to morphology. Images of thermomagnetically written bits in magneto-optical TbFeCo media proof the reliability of the writing process and the importance of an exact thermal design of the systems. Domains observed at corresponding Co L edges proof the chemical sensitivity of M-TXM and its potential to image few monolayer systems. C1 LBNL, CXRO, Berkeley, CA 94720 USA. Univ Wurzburg, EP IV, D-97074 Wurzburg, Germany. Univ Regensburg, D-93053 Regensburg, Germany. Nagoya Univ, Dept Elect, Nagoya, Aichi 4648063, Japan. SANYO, Hypermed Res Cent, Gifu 5030195, Japan. RP Fischer, P (reprint author), LBNL, CXRO, Berkeley, CA 94720 USA. RI Fischer, Peter/A-3020-2010 OI Fischer, Peter/0000-0002-9824-9343 NR 12 TC 9 Z9 9 U1 0 U2 5 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 325 EP 327 DI 10.1107/S0909049500015089 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100076 PM 11512768 ER PT J AU Pease, DM Daniel, M Budnick, JI Taylor, B Frenkel, A Pandya, K Grigorieva, IK Antonov, AA AF Pease, DM Daniel, M Budnick, JI Taylor, B Frenkel, A Pandya, K Grigorieva, IK Antonov, AA TI Extension of a tuned log spiral of revolution fluorescence XAFS detector, designed for optimal detection of a particular element Z, to XAFS of elements other than Z SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE dilute species XAFS; fluorescence XAFS AB Recently, it has been demonstrated that an x-ray detector in the form of a log spiral of revolution, covered with highly oriented pyrolytic graphite, is an excellent device for obtaining the fluorescence XAFS of an element of interest in the presence of competing fluorescence from other elements. In the present work we investigate the capabilities of a log spiral of revolution (LSR) detector, with a geometry optimized for one element (in this case Cr), if used for XAFS of other elements. C1 Univ Connecticut, Dept Phys, Storrs, CT 06268 USA. Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Optigraph Corp, Moscow, Russia. RP Pease, DM (reprint author), Univ Connecticut, Dept Phys, Storrs, CT 06268 USA. RI Frenkel, Anatoly/D-3311-2011 OI Frenkel, Anatoly/0000-0002-5451-1207 NR 9 TC 2 Z9 2 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 336 EP 338 DI 10.1107/S0909049500017052 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100080 PM 11512772 ER PT J AU Heald, S Stern, E Brewe, D Gordon, R Crozier, D Jiang, DT Cross, J AF Heald, S Stern, E Brewe, D Gordon, R Crozier, D Jiang, DT Cross, J TI XAFS at the Pacific Northwest Consortium-Collaborative Access Team undulator beamline SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE undulator beamline; microfocusing; MBE AB The Pacific Northwest Consortium-Collaborative Access Team (PNC-CAT) has begun operating an insertion device beamline at the Advanced Photon Source. The beamline has been extensively used for XAFS studies. This paper summarizes its capabilities, and our initial operational experience. The beamline is based on APS undulator A, and incorporates full undulator scanning. The monochromator is liquid nitrogen cooled and has both Si(111) and Si(311) crystals in a side-by-side configuration. Crystal changes only take a few minutes. The crystals cover the energy range from 3-50 keV with fluxes as high as 2x10(13) ph/sec. Microbeams can be produced using Kirkpatrick-Baez mirrors (spot size 1-3 mm) or tapered capillaries (sub-mm spots). When these optics are combined with a 13-element Ge detector, the beamline provides powerful microbeam imaging and spectroscopy capabilities. Experimental examples from the environmental field and in-situ UHV film growth will be discussed. C1 PNNL, Argonne, IL 60439 USA. Univ Washington, Seattle, WA 98195 USA. Simon Fraser Univ, Burnaby, BC V5A 1S6, Canada. Canadian Light Source, Saskatoon, SK, Canada. RP Heald, S (reprint author), PNNL, Bldg 435E, Argonne, IL 60439 USA. NR 7 TC 30 Z9 30 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 342 EP 344 DI 10.1107/S0909049500015946 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100082 PM 11512774 ER PT J AU Muramatsu, Y Ueno, Y Sasaki, TA Gullikson, EM Perera, RCC AF Muramatsu, Y Ueno, Y Sasaki, TA Gullikson, EM Perera, RCC TI Experimental technique for radiative-process-resolved X-ray absorption spectroscopy at the inner-shell excitation thresholds SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE x-ray absorption; x-ray emission process; graphite; diamond; boron nitride ID GRAPHITE; DIAMOND; SCATTERING AB Partial-fluorescence-yield (PFY) x-ray absorption measurements, using the optimized window widths of position sensitive detectors in wave-length dispersive x-ray spectrometers, have been applied for radiative-process-resolved (RPR) x-ray absorption spectroscopy. We have measured PFY-absorption spectra of graphite and diamond at the C K threshold and of h-BN and c-BN at the B K threshold. Resonant elastic x-ray scattering was observed in graphite and h-BN on their PFY-absorption spectra, and excitonic x-ray scattering was observed in diamond and c-BN. These results show that PFY-absorption measurements for RPR x-ray absorption spectroscopy can provide the information about the electronic structures and the radiative-decay process in inner-shell excitation. C1 Japan Atom Energy Res Inst, Hyogo 6795148, Japan. NTT, Lifestyle & Environm Technol Labs, Kanagawa 2430198, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Muramatsu, Y (reprint author), Japan Atom Energy Res Inst, Hyogo 6795148, Japan. RI Ueno, Yuko/H-5651-2012 NR 10 TC 2 Z9 2 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 369 EP 371 DI 10.1107/S0909049500015867 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100091 PM 11512783 ER PT J AU Drager, G Kirchner, T Bocharov, S Kao, CC AF Drager, G Kirchner, T Bocharov, S Kao, CC TI Spin-resolved NEXAFS from resonant X-ray scattering (RXS) SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE spin-resolved NEXAFS; resonant X-ray scattering; 3d-transition metal oxides ID MNO AB Resonantly excited metal K core line spectra of NiO, MnO, CoO and other compounds have been investigated at the beamlines X21 (NSLS/BNL), BW1 and W1.1 (HASYLAB/DESY). From analysis of spectral data we have drawn the following conclusions: -spin conservation is valid in the scattering process, for excitations below the absorption threshold as well as above it, -the absorption thresholds are different for spin-up and spin-down components of resonantly scattered spectra, -quadrupole transitions are very important or even crucial in the excitation process. Provided that these conclusions are true, a novel technique for quantitative resolution of NEXAFS spectra into spin-up and spin-down components has been developed. Since the method employs spin conservation and local spin references, it needs no circularly polarized radiation and no sample magnetization for taking both the RXS and NEXAFS spectra. Hence antiferromagnetic and paramagnetic materials can be investigated as well. Utilizing linear dichroism by angular-dependent measurements on single-crystal samples additional resolution of NEXAFS spectra is possible with respect to the orbital symmetry. Application of the method to paramagnetic MnO, for the first time, provides new and unambiguous experimental results confirming modern (LSDA+U) calculations: The metal K pre-edge XAS of MnO has predominantly 3d(t2g and eg) spin-down character. On the other hand, the delocalized p-like states, arising from the p-d band effect hybridization have spin-up character. C1 Univ Halle Wittenberg, Fachbereich Phys, D-06108 Halle, Germany. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. RP Drager, G (reprint author), Univ Halle Wittenberg, Fachbereich Phys, D-06108 Halle, Germany. NR 5 TC 7 Z9 7 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 398 EP 400 DI 10.1107/S0909049500017234 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100101 PM 11512793 ER PT J AU Wende, H Wilhelm, F Poulopoulos, P Rogalev, A Schlagel, DL Lograsso, TA Baberschke, K AF Wende, H Wilhelm, F Poulopoulos, P Rogalev, A Schlagel, DL Lograsso, TA Baberschke, K TI Magnetic EXAFS at Gd L-edges: the spin-pir-distribution function of Gd neighbors SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE temperature-dependent magnetic EXAFS ID X-RAY-ABSORPTION; FULLY RELATIVISTIC THEORY; FINE-STRUCTURE; MULTIPLE-SCATTERING; CIRCULAR-DICHROISM; 3D ELEMENTS AB The purpose of the experiment is to study the normal and the Magnetic EXAFS (MEXAFS) since EXAFS is the method of choice to investigate the local pair- and spin-pair-distribution function. We present MEXAFS and EXAFS measurements at the L-edges of a Gd single crystal in the temperature range of 10 K to 250 K. Therefore we are able to investigate the MEXAFS in a wide range of the reduced temperature t =T/T-c of 0.04 less than or equal to t less than or equal to 0.85 with T-c = 293 K. We find a strong decrease of the nearest neighbor EXAFS which retains only about 35% of its 10 K value already at 250 K. This highlights the importance of lattice vibrations. To analyze the individual scattering contributions to the MEXAFS and the EXAFS, ab initio calculations (FEFF code) have been carried out. The comparison of the temperature-dependent damping of the normal EXAFS with the spin-dependent MEXAFS allows us to separate the influence of lattice vibrations (Debye temperature 160 K) from the magnetic ordering (Curie temperature) on the MEXAFS. C1 Free Univ Berlin, Inst Expt Phys, D-14195 Berlin, Germany. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Baberschke, K (reprint author), Free Univ Berlin, Inst Expt Phys, Arnimallee 14, D-14195 Berlin, Germany. RI Wende, Heiko/J-8505-2012 NR 21 TC 4 Z9 4 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 MAR PY 2001 VL 8 BP 419 EP 421 DI 10.1107/S0909049500016915 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100108 PM 11512800 ER PT J AU Hahlin, A Karis, O Brena, B Dunn, JH Arvanitis, D AF Hahlin, A Karis, O Brena, B Dunn, JH Arvanitis, D TI Quantitative analysis of L-edge white line intensities: the influence of saturation and transverse coherence SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN ID CIRCULAR-DICHROISM; RAY C1 Univ Uppsala, Dept Phys, Uppsala, Sweden. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Hahlin, A (reprint author), Univ Uppsala, Dept Phys, Box 530, Uppsala, Sweden. RI Brena, Barbara/C-5909-2014; OI Karis, Olof/0000-0001-6406-217X NR 9 TC 1 Z9 1 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 437 EP 439 DI 10.1107/S0909049500018367 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100114 PM 11512806 ER PT J AU Dunn, JH Arvanitis, D Carr, R Martensson, N AF Dunn, JH Arvanitis, D Carr, R Martensson, N TI Magnetisation reorientation in ultra-thin Fe films on Cu(100) upon deposition of Co SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE ultrathin films; magnetic anisotropy energy; XMCD ID TRANSITION; SPIN AB Ultra thin films of Fe deposited on the (100) surface of a Cu single crystal exhibit a net perpendicular magnetic anisotropy. The addition of very low coverages of Co results in the easy magnetic direction reorienting into the film plane. This behavior is in contrast to the addition of similar amounts of Fe, whereupon the ferromagnetic response vanishes. This result is discussed in terms of the anisotropy energies derived from the spectroscopic data. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. RP Dunn, JH (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 463 EP 465 DI 10.1107/S090904950001863X PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100123 PM 11512815 ER PT J AU Yaita, T Tachimori, S Edelstein, NM Bucher, JJ Rao, L Shuh, DK Allen, PG AF Yaita, T Tachimori, S Edelstein, NM Bucher, JJ Rao, L Shuh, DK Allen, PG TI EXAFS studies of americium (III)-benzimidazole complex in ethanol SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE americium; benzimidazole; EXAFS; ethanol; neodymium; structure ID CHLORIDE SOLUTIONS; SEPARATION; LIGANDS AB The local structures of Am, Nd and Er-Benzimidazole (Biz) in solution were determined by EXAFS. The BIZ molecule coordinated to Am and Nd through two nitrogen atoms in a bidentate fashion. Two nitrogen atoms of BIZ ligated to Am and Nd with the bond distances RAm-N=2.63 Angstrom and RNd-N = 2.65 Angstrom, respectively. The total coordination number of the Am BIZ complexes (at a molar ratio of metal ion to ligand of 1:20) was similar to 10 but that of Nd BIZ complex was similar to 9. C1 Japan Atom Energy Res Inst, Dept Mat Sci, Tokai, Ibaraki 3191195, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Glenn T Seaborg Inst Transactinium Sci, Livermore, CA 94551 USA. RP Yaita, T (reprint author), Japan Atom Energy Res Inst, Dept Mat Sci, Tokai, Ibaraki 3191195, Japan. NR 10 TC 9 Z9 9 U1 2 U2 7 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 MAR PY 2001 VL 8 BP 663 EP 665 DI 10.1107/S0909049500019415 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100191 PM 11512888 ER PT J AU Frenkel, AI Vairavamurthy, M Newville, M AF Frenkel, AI Vairavamurthy, M Newville, M TI A study of the coordination environment in aqueous cadmium-thiol complexes by EXAFS spectroscopy: experimental vs. theoretical standards SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE dilute solutions; thiols; cadmium complexation AB Using EXAFS, we investigated the changes in the local structure of Cd(II) complexes formed with a series of low-molecular-weight thiols at different thiol/cadmium stoichiometries. For dilute solutions, a comparison of theoretical and experimental standards proved the latter approach superior. The number of bound oxygen atoms decreased while the number of sulfur atoms increased as the thiol/cadmium ratios increased, indicating that up to four thiol compounds can bind to cadmium in aqueous solutions. The computer code FEFFIT was modified to employ experimental and theoretical standards with equal facility. C1 Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. Univ Chicago, Argonne Natl Lab, GEO CARS, Argonne, IL 60439 USA. RP Frenkel, AI (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Bldg 510 E, Upton, NY 11973 USA. RI Frenkel, Anatoly/D-3311-2011 OI Frenkel, Anatoly/0000-0002-5451-1207 NR 4 TC 10 Z9 10 U1 1 U2 6 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 669 EP 671 DI 10.1107/S0909049500016757 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100193 PM 11512890 ER PT J AU Glover, CJ Ridgway, MC Yu, KM Foran, GJ Clerc, C Hansen, JL Nylandsted-Larsen, A AF Glover, CJ Ridgway, MC Yu, KM Foran, GJ Clerc, C Hansen, JL Nylandsted-Larsen, A TI Structure and low- temperature thermal relaxation of ion- implanted germanium SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE extended X-ray absorption fine structure; spectroscopy; amorphous Germanium; ion implantation ID AMORPHOUS-GERMANIUM; GE; MICROSTRUCTURE; CRYSTALLINE; DISORDER; LIQUID; ORDER; SI AB The structure of implantation-induced damage in Ge has been investigated using high resolution extended X-ray absorption fine structure spectroscopy (EXAFS). EXAFS data analysis was performed with the Cumulant Method. For the crystalline-to-amorphous transformation, a progressive increase in bond-length was observed without the presence of an asymmetry in interatomic distance distribution (RDF). Beyond the amorphization threshold the RDF was dose dependent and asymmetric, where the bond-length and asymmetry increased as functions of ion dose. Such an effect was attributed to the formation of three- and five-fold coordinated atoms within the amorphous phase. Low-temperature thermal annealing resulted in structural relaxation of the amorphous phase as evidenced by a reduction in the centroid, asymmetry and width of the RDF, as consistent with a reduction in the fraction of non four-fold coordinated atoms. The results have been compared to other EXAFS studies of amorphous Ge, and it is suggested that the range of bond-lengths reported therein is related to the sample preparation method and state of relaxation. C1 Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT, Australia. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. CNRS, F-91405 Orsay, France. Univ Aarhus, Inst Phys & Astron, Aarhus, Denmark. RP Glover, CJ (reprint author), Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT, Australia. RI Yu, Kin Man/J-1399-2012; Ridgway, Mark/D-9626-2011 OI Yu, Kin Man/0000-0003-1350-9642; Ridgway, Mark/0000-0002-0642-0108 NR 13 TC 2 Z9 2 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 773 EP 775 DI 10.1107/S0909049500012620 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100228 PM 11512927 ER PT J AU Cross, JO Newville, M Hellman, F Rooney, PW Shapiro, AL Harris, VG AF Cross, JO Newville, M Hellman, F Rooney, PW Shapiro, AL Harris, VG TI Growth induced magnetic and chemical anisotropy in CoPt3 alloy films SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN AB We report the results of polarized Co K EXAFS experiments on a series of CoPt3 films grown by molecular beam epitaxy on (100) MgO single crystal substrates over a range of temperatures from 473 K to 1073 K. These samples exhibit substantial perpendicular magnetic anisotropy that is strongly dependent on the substrate growth temperature T-g. We measure a preference for in-plane Co-Co pairs that is correlated with the magnetic properties. C1 Argonne Natl Lab, Adv Photon Source, PNC, CAT, Argonne, IL 60439 USA. Univ Chicago, Chicago, IL 60637 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. USN, Res Lab, Complex Mat Sect, Washington, DC 20375 USA. RP Cross, JO (reprint author), Argonne Natl Lab, Adv Photon Source, PNC, CAT, Argonne, IL 60439 USA. RI Harris, Vincent/A-8337-2009 NR 12 TC 6 Z9 6 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 880 EP 882 DI 10.1107/S0909049501000309 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100264 PM 11512965 ER PT J AU Ignatov, AY Khalid, S Sujoy, R Ali, N AF Ignatov, AY Khalid, S Sujoy, R Ali, N TI Theoretical study of Mn K-edge in La1-xCaxMnO3 SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE spin-polarized XANES; Mn 3d-O 2p hybridization ID LA1-XSRXMNO3; TRANSITION; MANGANITES; DICHROISM AB Effects of (i) local magnetic ordering, (ii) lattice distortions, and (iii) Mn 3d - O 2p hybridization on the shape of Mn K- edge XANES spectra of La1-xCaxMnO3 have been evaluated numerically and compared with available experimental data. We calculated the spin-polarized Mn K- edge spectra. An energy splitting between spin-up and spin-down XANES of 0.5-1.1 eV contributes to the broadening of the total XANES below T-N(T-c). To simulate lattice polaronic distortions across a MI transition the Mn K-edge spectra were calculated twice: assuming R-3c (R=1.96 Angstrom) and Pbnm (R-1=1.91, R-2=1.97, and R-3=2.16 Angstrom) symmetries. Results could qualitatively reproduce the observed energy "shift" across the transition. A pre-edge peak at E similar to 6542 eV and feature B-3 at similar to6 eV above the main peak were found to be related to the Mn 3d - O 2p hybridization. The feature B-3 should be assigned to a shake-up transition. The calculated K-edge spectrum was obtained as a convolution product of the single-electron XANES and the spectrum of many-body excitations in the Mn-O electronic states in the presence of the 1s core-hole. C1 New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. So Illinois Univ, Dept Phys, Carbondale, IL 62901 USA. RP Ignatov, AY (reprint author), New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA. NR 14 TC 6 Z9 6 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 898 EP 900 DI 10.1107/S0909049501000358 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100270 ER PT J AU Kelly, SD Kemmer, KM Fryxell, GE Liu, J Mattigod, S AF Kelly, SD Kemmer, KM Fryxell, GE Liu, J Mattigod, S TI X-ray absorption fine structure spectroscopy determination of the binding mechanism of tetrahedral anions to self assembled monolayers on mesoporous support SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE SAMMS; actinides; environment ID SPECTRA AB X-ray absorption fine structure (XAFS) spectroscopy is used to investigate the chemical interaction between the end member [Cu(NH2)(6)] of self-assembled monolayers on mesoporous supports (SAMMS) and the tetrahedral anion SO4. The local structure about Cu indicates monodentate bonding between the SO4 anion and the SAMMS. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Kelly, SD (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI ID, MRCAT/G-7586-2011 NR 4 TC 0 Z9 0 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 922 EP 924 DI 10.1107/S0909049500021002 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100278 PM 11512980 ER PT J AU Kelly, SD Boyanov, MI Bunker, BA Fein, JB Fowle, DA Yee, N Kemner, KM AF Kelly, SD Boyanov, MI Bunker, BA Fein, JB Fowle, DA Yee, N Kemner, KM TI XAFS determination of the bacterial cell wall functional groups responsible for complexation of Cd and U as a function of pH SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE environmental science; biogeochemistry; microbiology; uranium; cadmium ID ABSORPTION FINE-STRUCTURE; ADSORPTION; SPECTRA AB Bacteria, which are ubiquitous in near-surface geologic systems, can affect the distribution and fate of metals in these systems through adsorption reactions between the metals and bacterial cell walls. Recently, Fein et al. (1997) developed a chemical equilibrium approach to quantify metal adsorption onto cell walls, treating the sorption as a surface complexation phenomenon. However, such models are based on circumstantial bulk adsorption evidence only, and the nature and mechanism of metal binding to cell walls for each metal system have not been determined spectroscopically. The results of XAFS measurements at the Cd K-edge and U L3-edge on Bacillus subtilis exposed to these elements show that, at low pH, U binds to phosphoryl groups while Cd binds to carboxyl functional groups. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Fowle, David/B-1074-2008; ID, MRCAT/G-7586-2011 NR 16 TC 44 Z9 44 U1 3 U2 14 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 1600-5775 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 946 EP 948 DI 10.1107/S0909049500021014 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100286 PM 11512988 ER PT J AU Kemner, KM Kelly, SD Orlandini, KA Tsapin, AI Goldfeld, MG Perfiliev, YD Nealson, KH AF Kemner, KM Kelly, SD Orlandini, KA Tsapin, AI Goldfeld, MG Perfiliev, YD Nealson, KH TI XAS investigations of Fe(VI) SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE astrobiology; biosignature; biogeochemistry; environmental science; XAFS ID ABSORPTION FINE-STRUCTURE; SPECTRA AB Recent attention has been given to a reexamination of results from the early Viking missions to Mars that suggested the presence of one or more strong oxidants in Martian soil. Since Fe is one of the main constituents of the Martian surface and Fe( VI) is known to be a highly reactive, strong oxidant, we have made XANES and EXAFS measurements of Fe( II), Fe( III), Fe( IV), and Fe( VI) in solid and solution forms. Results from these studies indicate a preedge XANES feature from Fe( VI) samples similar to that commonly seen from Cr( VI) samples. Results of first shell analysis indicate a linear relationship between the Fe-O bondlength and Fe valence state. C1 Argonne Natl Lab, Argonne, IL 60439 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Moscow MV Lomonosov State Univ, Sch Chem, Moscow, Russia. RP Kemner, KM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM kemner@anl.gov RI ID, MRCAT/G-7586-2011 NR 16 TC 10 Z9 10 U1 1 U2 5 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 1600-5775 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 949 EP 951 DI 10.1107/S0909049500021026 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100287 PM 11512989 ER PT J AU Montano, PA Linton, J Thieu, V Halpern, Y AF Montano, PA Linton, J Thieu, V Halpern, Y TI Local structure of guest molecules in gas hydrates - a model study of Kr and Xe clathrates SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE clathrates; krypton; xenon; diffraction; pressure; hydrates ID HYDROPHOBIC HYDRATION AB Gas hydrates constitute a class of solids in which small molecules occupy cavities inside an ice-like structure. There is enormous scientific and technological interest in understanding the structure, stability and formation mechanism of clathrates. We developed and constructed a variable temperature high-pressure cell for x-rays measurements, which allows in situ studies of clathrate formation or decomposition. We used XAFS and Diffraction techniques to study the evolution of the structure during formation and decomposition. We studied two clathrates structures, structure I (Xe) and structure II (Kr). We were able to identify the local structure around the guest atom. We identified the rare gas-water complexes that act as precursor to the formation of the crystalline phases. We observed the transformation of the clathrate from structure II to structure I when Xe is added to Kr clathrates. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Illinois, Dept Phys, Chicago, IL 60680 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Montano, PA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 6 TC 8 Z9 8 U1 2 U2 7 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 MAR PY 2001 VL 8 BP 972 EP 974 DI 10.1107/S0909049500013686 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100295 PM 11512998 ER PT J AU Rompel, A Cinco, RM Robblee, JH Latimer, MJ McFarlane, KL Huang, J Walters, MA Yachandra, VK AF Rompel, A Cinco, RM Robblee, JH Latimer, MJ McFarlane, KL Huang, J Walters, MA Yachandra, VK TI S K- and Mo L-edge X-ray absorption spectroscopy to determine metal-ligand charge distribution in molybdenum-sulfur compounds SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 11th International Conference on X-ray Absorption Fine Structure (XAFS XI) CY JUL 26-31, 2000 CL AKO, JAPAN DE SK-edge; pre-edge; XAS; redox potential; hydrogen bonding ID REDOX POTENTIALS; COMPLEXES; RUBREDOXIN; ANALOGS AB Mo L-edge and S K-edge X-ray absorption spectroscopy were applied to investigate the charge distribution between Mo and S in a series of Mo thiolate compounds, which serve as amide-sulfur H-bonding models and exhibit different redox potentials arising from polar group effects and ligand hydrogen bonds near the redox center. For all oxidized complexes, the S K-edge spectra exhibit a thiolate-based pre-edge feature centered at 2470.2 eV and the inflection point occurs at 2472.0 eV. No intense pre-edge feature is observed in the spectra for the reduced Mo model compounds and the energy shift of the S K-edge position depends on the S-ligand. Correlations between ligand charge density and the redox potential of the Mo-S cores are observed. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Melvin Calvin Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NYU, Dept Chem, New York, NY 10003 USA. RP Rompel, A (reprint author), Univ Munster, D-48149 Munster, Germany. FU NIGMS NIH HHS [R01GM 47933] NR 11 TC 8 Z9 8 U1 1 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAR PY 2001 VL 8 BP 1006 EP 1008 DI 10.1107/S0909049500017702 PN 2 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 407YC UT WOS:000167298100307 PM 11512702 ER PT J AU Swift, GW Spoor, PS AF Swift, GW Spoor, PS TI Thermal diffusion and mixture separation in the acoustic boundary layer (vol 106, pg 1794, 1999) SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Correction 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 1 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAR PY 2001 VL 109 IS 3 BP 1261 EP 1261 DI 10.1121/1.1348007 PG 1 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 409DM UT WOS:000167369300038 ER PT J AU Apte, MG Lefohn, AS AF Apte, MG Lefohn, AS TI Untitled SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Letter C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Apte, MG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA ONE GATEWAY CENTER, THIRD FL, PITTSBURGH, PA 15222 USA SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD MAR PY 2001 VL 51 IS 3 BP 322 EP 322 PG 1 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 411WD UT WOS:000167521500001 PM 11266096 ER PT J AU Han, YS Kim, DK Gilbert, CJ Ritchie, RO AF Han, YS Kim, DK Gilbert, CJ Ritchie, RO TI Cyclic fatigue-crack propagation behavior in silicon carbide: Long- and small-crack behavior SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID RESISTANCE-CURVE BEHAVIOR; B-C ADDITIONS; FRACTURE-TOUGHNESS; CERAMICS; ALUMINA; GROWTH; THICKNESS AB Cyclic fatigue properties of high-toughness SiC with additives of Al2O3 and Y2O3 were examined, with a focus on differences between long- (>3 mm) and small-crack (<200 m) behavior. Small cracks were initiated with Vickers indents placed on the tensile surfaces of beams, and crack extension was monitored optically under cyclic load. For small cracks, high growth rates which exhibited a negative dependence on the far-field driving force were observed. Such behavior was explained by both indent-induced residual stresses and the relative size of cracks compared with bridging zone lengths. C1 Korea Adv Inst Sci & Technol, Dept Mat Sci & Engn, Yusong Gu, Taejon 305701, South Korea. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Han, YS (reprint author), Korea Adv Inst Sci & Technol, Dept Mat Sci & Engn, Yusong Gu, 373-1 Kusung Dong, Taejon 305701, South Korea. RI Ritchie, Robert/A-8066-2008; Kim, Do Kyung/C-2039-2011 OI Ritchie, Robert/0000-0002-0501-6998; Kim, Do Kyung/0000-0001-9092-9427 NR 20 TC 3 Z9 3 U1 0 U2 4 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 MAR PY 2001 VL 84 IS 3 BP 551 EP 554 PG 4 WC Materials Science, Ceramics SC Materials Science GA 410YN UT WOS:000167468800011 ER PT J AU Xu, HW Navrotsky, A Balmer, ML Su, YL Bitten, ER AF Xu, HW Navrotsky, A Balmer, ML Su, YL Bitten, ER TI Energetics of substituted pollucites along the CsAlSi2O6-CsTiSi2O6.5 join: A high-temperature calorimetric study SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID POWDER DIFFRACTION DATA; PHASE-TRANSITIONS; THERMAL-EXPANSION; CRYSTAL-STRUCTURE; LEUCITE; CESIUM; ORDER; THERMOCHEMISTRY; CSTISI2O6.5; ZEOLITES AB Enthalpies of drop solution for a suite of substituted pollucites with the compositions CsTixAl1-xSi2O6+0.5x, 0 less than or equal tox less than or equal to1, which are synthesized using the sol-gel method, have been measured in molten lead berate (2PbO .B2O3) at 701 degreesC. As Ti4+ substitutes for Al3+, the enthalpies of drop solution become less endothermic and show exothermic heats of mixing within the composition range from x = 0.3 to 1. This nonideal mixing behavior is consistent with the trend seen in variation of lattice parameters, and we interpret it to be a result of the short-range order associated with the framework cations Al3+, Si4+, and Ti4+ in the structure. Using enthalpies of drop solution of SiO2, Al2O3, TiO2, and Cs2O, standard molar enthalpies of formation of these phases from their constituent oxides and from the elements are derived for the first time. C1 Univ Calif Davis, Thermochem Facil, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Xu, HW (reprint author), Univ Calif Davis, Thermochem Facil, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. NR 50 TC 17 Z9 17 U1 1 U2 6 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 MAR PY 2001 VL 84 IS 3 BP 555 EP 560 PG 6 WC Materials Science, Ceramics SC Materials Science GA 410YN UT WOS:000167468800012 ER PT J AU Vogt, T Hunter, BA Thornton, J AF Vogt, T Hunter, BA Thornton, J TI Structural evolution of thermal-sprayed yttria-stabilized ZrO2 thermal barrier coatings with annealing - A neutron diffraction study SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article AB We studied the influence of the annealing temperature on the atomic structure of yttria-stabilized tetragonal zirconia (YSZ) which was deposited as a 300 mum thick thermal barrier coating (TBC) on nickel superalloy substrates by plasma spraying. To obtain neutron powder diffraction patterns of the barrier coatings we used an experimental technique where the sample is randomly rotated in the neutron beam. The time-averaged neutron diffraction pattern was then analyzed using the Rietveld refinement technique without any need for corrections. This allowed the comparison of the average crystals structures from bulk tetragonal samples obtained via common ceramic routes and those of micrometer thick films deposited on substrates using plasma spray or other nonequilibrium techniques. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Def Sci & Technol Org, Airframes & Engines Div, Melbourne, Vic 3001, Australia. RP Vogt, T (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Vogt, Thomas /A-1562-2011 OI Vogt, Thomas /0000-0002-4731-2787 NR 8 TC 8 Z9 8 U1 0 U2 6 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 MAR PY 2001 VL 84 IS 3 BP 678 EP 680 PG 3 WC Materials Science, Ceramics SC Materials Science GA 410YN UT WOS:000167468800041 ER PT J AU Tang, KQ Smith, RD AF Tang, KQ Smith, RD TI Physical/chemical separations in the break-up of highly charged droplets from electrosprays SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID MASS-SPECTROMETRY; IONIZATION; DEPENDENCE; ANALYTES; FISSION; TIME AB Highly-charged droplets, as formed by an electrospray process, are known to undergo asymmetric fission to form smaller droplets. We have observed a chemical and physical separation phenomenon that occurs in the droplet break-up process and is related to a compound's surface activity in solution. Two experimental approaches demonstrated that the smaller satellite droplets and the progeny droplets generated by the spray formation and asymmetric fission processes to be surfactant-enriched, These smaller droplets were also effectively separated from the larger primary and residual droplets because of their smaller inertia and high surface charge density, and a region attributed to the initially formed smaller satellite droplets was found to be strikingly confined in a narrow periphery region of the electrospray. The phenomenon may have utility for chemical separations and have significant implications for the sensitivity and selectivity of electrospray ionization-mass spectrometry. (C) 2001 American Society for Mass Spectrometry. 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, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 20 TC 63 Z9 64 U1 1 U2 16 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD MAR PY 2001 VL 12 IS 3 BP 343 EP 347 DI 10.1016/S1044-0305(01)00222-7 PG 5 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 408WB UT WOS:000167349200013 PM 11281610 ER PT J AU Chartouni, D Gross, K AF Chartouni, D Gross, K TI Phase transitions in LaNi4Co during electrochemical cycling an in situ X-ray diffraction study SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID NEUTRON POWDER DIFFRACTION; HYDROGEN ABSORPTION; METAL HYDRIDE; ALLOYS; STABILITY; DESORPTION; ELECTRODES; BEHAVIOR AB Phase and crystal structure changes during the electrochemical hydriding and dehydriding of LaNi4Co were investigated using in situ X-ray diffraction (XRD). A specially designed cell allowed dynamic XRD measurements during five charge-discharge cycles. This enabled the direct observation of the activation process. In addition, crystal lattice information derived from these measurements help to explain the long cycle life of cobalt containing AB(5)-type battery alloys. The formation of an intermediate gamma -phase hydride between the hydrogen solid-solution alpha -phase and the fully hydrided beta -phase was clearly observed during absorption and desorption. The volume expansion in the formation of the gamma and beta hydride phases is highly anisotropic. Lattice expansion in the alpha -phase to gamma -phase transformation occurs mainly in the basal plane, whereas the transition from the gamma -phase to the beta -phase causes a lattice expansion in the c axis direction. It is believed that the two-step phase transition in this Co-substituted alloy generates less internal stress than the single-step volume expansion of the archetype LaNi5 compound. This reduces the stress-induced pulverization that occurs during electrochemical cycling. Consequently, the metal hydride electrode maintains larger particle sizes and, thus, smaller surface areas subject to corrosion by the electrolyte, which is the principle cause of capacity loss. (C) 2001 The Electrochemical Society. All rights reserved. C1 Univ Fribourg, Inst Phys, CH-1700 Fribourg, Switzerland. Sandia Natl Labs, Analyt Mat Sci Dept, Livermore, CA 94551 USA. RP Chartouni, D (reprint author), Univ Fribourg, Inst Phys, CH-1700 Fribourg, Switzerland. NR 35 TC 8 Z9 8 U1 1 U2 6 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAR PY 2001 VL 148 IS 3 BP A241 EP A248 DI 10.1149/1.1350656 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 412GB UT WOS:000167545700010 ER EF