FN Thomson Reuters Web of Science™ VR 1.0 PT J AU ROBERTO, FF GLENN, AW BULMER, D WARD, TE AF ROBERTO, FF GLENN, AW BULMER, D WARD, TE TI GENETIC TRANSFER IN ACIDOPHILIC BACTERIA WHICH ARE POTENTIALLY APPLICABLE IN COAL BENEFICIATION SO FUEL LA English DT Article; Proceedings Paper CT SYMP ON BIOTECHNOLOGY FOR THE PRODUCTION OF CLEAN FUELS CY AUG 27-28, 1990 CL WASHINGTON, DC DE DESULFURIZATION; ACIDOPHILIC BACTERIA; CONJUGATION ID GRAM-NEGATIVE BACTERIA; HOST-RANGE; DESULFURIZATION AB The transfer of genetic information into acidophilic (acid requiring) bacteria, and the production of suitable vectors for these cells are being investigated in order to develop genetic engineering systems for them. Such cells may prove useful in the biological desulphurization of coal, and these procedures are needed to take full advantage of their capabilities. Plasmids from different incompatibility groups were tested to determine the frequency with which they are transferred from Escherichia coli to Acidiphilium strains. IncP1 and IncQ plasmids were transferred at moderate efficiencies, whereas IncW plasmids were transferred much less efficiently. A conjugative function has been discovered in Acidiphilium strains by observing the transfer of mobilizable, but not self-transmissible, plasmids between Acidiphilium cells. Finally, a small, cryptic plasmid from Thiobacillus ferrooxidans has been cloned and partially characterized. RP ROBERTO, FF (reprint author), IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415, USA. NR 24 TC 2 Z9 3 U1 0 U2 0 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0016-2361 J9 FUEL JI Fuel PD MAY PY 1991 VL 70 IS 5 BP 595 EP 598 DI 10.1016/0016-2361(91)90172-7 PG 4 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA FL494 UT WOS:A1991FL49400007 ER PT J AU STAVERT, DM ARCHULETA, DC BEHR, MJ LEHNERT, BE AF STAVERT, DM ARCHULETA, DC BEHR, MJ LEHNERT, BE TI RELATIVE ACUTE TOXICITIES OF HYDROGEN-FLUORIDE, HYDROGEN-CHLORIDE, AND HYDROGEN BROMIDE IN NOSE-BREATHING AND PSEUDO-MOUTH-BREATHING RATS SO FUNDAMENTAL AND APPLIED TOXICOLOGY LA English DT Article ID RESPIRATORY AIR-FLOW; DIOXIDE; AIRWAYS; MICE; LUNG C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV LIFE SCI,CELLULAR & MOLEC BIOL GRP,PULM BIOL & TOXICOL SECT,LOS ALAMOS,NM 87544. NR 42 TC 35 Z9 36 U1 0 U2 2 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0272-0590 J9 FUND APPL TOXICOL JI Fundam. Appl. Toxicol. PD MAY PY 1991 VL 16 IS 4 BP 636 EP 655 DI 10.1016/0272-0590(91)90152-T PG 20 WC Toxicology SC Toxicology GA FJ691 UT WOS:A1991FJ69100003 PM 1653158 ER PT J AU SCHWETZ, BA MAST, TJ WEIGEL, RJ DILL, JA MORRISSEY, RE AF SCHWETZ, BA MAST, TJ WEIGEL, RJ DILL, JA MORRISSEY, RE TI DEVELOPMENTAL TOXICITY OF INHALED METHYL ETHYL KETONE IN SWISS MICE SO FUNDAMENTAL AND APPLIED TOXICOLOGY LA English DT Article ID N-BUTYL KETONE; RATS; EMBRYOTOXICITY; FETOTOXICITY; INHALATION C1 NIEHS, DIV TOXICOL RES & TESTING, DEV & REPROD TOXICOL GRP, RES TRIANGLE PK, NC 27709 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 17 TC 8 Z9 8 U1 1 U2 5 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0272-0590 J9 FUND APPL TOXICOL JI Fundam. Appl. Toxicol. PD MAY PY 1991 VL 16 IS 4 BP 742 EP 748 DI 10.1016/0272-0590(91)90160-6 PG 7 WC Toxicology SC Toxicology GA FJ691 UT WOS:A1991FJ69100011 PM 1884913 ER PT J AU KU, LP HENDEL, HW LIEW, SL STRACHAN, JD AF KU, LP HENDEL, HW LIEW, SL STRACHAN, JD TI NUMERICAL SIMULATIONS OF INSITU NEUTRON DETECTOR CALIBRATION EXPERIMENTS ON THE TOKAMAK FUSION TEST REACTOR SO FUSION TECHNOLOGY LA English DT Article DE NEUTRON DETECTOR; NUMERICAL SIMULATION; TFTR ID EFFICIENCY AB Accurate determinations of fusion neutron yields on the Tokamak Fusion Test Reactor (TFTR) require that the neutron detectors be absolutely calibrated in situ, using neutron sources of known strengths. For such calibrations, numerical simulations of neutron transport can be powerful tools in the design of experiments and the study of measurement results. On the TFTR, numerical calibration experiments are frequently used to complement actual detector calibrations. Calculational approaches and transport models used in these numerical simulations are presented and the results from a simulation of the calibration of U-235 fission detectors carried out in December 1988 are summarized. RP KU, LP (reprint author), PRINCETON PLASMA PHYS LAB,POB 451,PRINCETON,NJ 08543, USA. NR 11 TC 4 Z9 4 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAY PY 1991 VL 19 IS 3 BP 418 EP 430 PN 1 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA FH427 UT WOS:A1991FH42700003 ER PT J AU SANTORO, RT ALSMILLER, RG BARNES, JM AF SANTORO, RT ALSMILLER, RG BARNES, JM TI REACTION-RATE DISTRIBUTIONS AND RELATED DATA IN THE FUSION NEUTRON SOURCE PHASE-II EXPERIMENTS - COMPARISON OF MEASURED AND CALCULATED DATA SO FUSION TECHNOLOGY LA English DT Article DE NEUTRONICS; ACTIVATION; TRITIUM BREEDING CONCEPTS ID STATES COLLABORATIVE PROGRAM; BLANKET NEUTRONICS AB Neutronics parameters including the source neutron spectrum, activation rates, and the tritium breeding in the Li2O test zone of the Fusion Neutron Source Phase II experiment performed at the Japan Atomic Energy Research Institute are calculated using the Monte Carlo code MORSE with ENDF/B-V transport and reaction cross sections. Favorable comparisons between the measured and calculated results are achieved for the Al-27(n, alpha), Ni-58(n,p), Nb-93(n,2n), and Au-197(n,2n) reactions. Calculated Ni-58(n,2n) and Au-197(n, gamma) reactions do not agree with measured values within 10 to 40%. For the nickel reaction, the differences may be due to poor data in the ORACT files, while discrepancies for the gold data may be due to unknown quantities of hydrogen-rich epoxy used to coat the Li2CO3 blocks used in the test assembly walls. The calculated tritium breeding in the Li2O agrees with experimental values within +/- 10% for Li-6 and +/- 15 to 20% for Li-7. RP SANTORO, RT (reprint author), OAK RIDGE NATL LAB,DIV ENGN PHYS & MATH,OAK RIDGE,TN 37831, USA. NR 19 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 SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAY PY 1991 VL 19 IS 3 BP 449 EP 459 PN 1 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA FH427 UT WOS:A1991FH42700006 ER PT J AU BARR, WL AF BARR, WL TI A MODEL FOR THE EDGE PLASMA NEAR A POLOIDAL DIVERTOR SO FUSION TECHNOLOGY LA English DT Article DE EDGE-PLASMA MODEL; SCRAPE-OFF LAYER; DIVERTOR PLASMA ID TOKAMAK AB A physics model is developed for estimating the principal parameters of the edge plasma in a large tokamak with a poloidal divertor. The model is essentially one-dimensional, but it includes transverse scale lengths that are derived from power balance. The model allows highly elongated magnetic configurations with either a double or a single null. The power flowing into the edge plasma, the power radiated from the edge plasma, and the power incident on the divertor are all assumed to be known. The plasma density at the separatrix is also assumed to be known. Equations developed from the model give the plasma temperature at the midplane separatrix, the plasma temperature and density at the divertor, and the transverse scale length for power flow in the edge plasma. The scaling relations for the plasma parameters and an expression for the peak heat flux at the divertor are derived. The basic assumption made in developing the model is that the transverse scale lengths can be mapped from one region in the edge plasma to another by the conservation of magnetic flux. RP BARR, WL (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,POB 808,LIVERMORE,CA 94550, USA. NR 11 TC 13 Z9 13 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAY PY 1991 VL 19 IS 3 BP 498 EP 502 PN 1 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA FH427 UT WOS:A1991FH42700011 ER PT J AU DIENES, JK AF DIENES, JK TI ON NUCLEAR-REACTIONS IN DEFECTS SO FUSION TECHNOLOGY LA English DT Note DE LATTICE DYNAMICS; FRENKEL-KONTOROVA DEFECTS; DYNAMIC FRACTURE ID FUSION; DEUTERIUM AB The variability of results concerning cold fusion, together with the difficulty of explaining the observations, suggests that some nonstandard processes may be occurring. One such possibility is that nuclear reactions occur in defects of a deuterated lattice as a result of transient motions that momentarily bring deuterium atoms into close proximity. A mechanism involving shear of a one-dimensional lattice is described that illustrates this possibility. Order-of-magnitude estimates indicate that the expected fusion rate is not inconsistent with some experiments. RP DIENES, JK (reprint author), UNIV CALIF LOS ALAMOS SCI LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. NR 19 TC 0 Z9 0 U1 1 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 MAY PY 1991 VL 19 IS 3 BP 543 EP 546 PN 1 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA FH427 UT WOS:A1991FH42700015 ER PT J AU SIPLEY, J STASSI, D DUNN, J GOLDMAN, E AF SIPLEY, J STASSI, D DUNN, J GOLDMAN, E TI ANALYSIS OF BACTERIOPHAGE T7 GENE 10A AND FRAMESHIFTED B-10 PROTEINS SO GENE EXPRESSION LA English DT Article ID ESCHERICHIA-COLI AB Bacteriophage T7 capsid protein 10B has previously been proposed to arise by a translational frameshift near the 3' end of the capsid gene 10A coding sequence, adding an additional 53 amino acid residues to the carboxyl-terminal end of the protein. Here we show by peptide mapping experiments as well as by direct partial sequence analysis of an overlapping "junction" peptide, that 10B is in fact related to 10A by a -1 switch in reading frame in a narrow region near the carboxy terminus of 10A. Peptide mapping experiments demonstrate that 10A and 10B have the same amino terminus as well as virtually identical methionine-labeled peptide maps. However, the predicted unique carboxyl-terminal peptide from 10B was also identified. An overlapping peptide was isolated from 10B which spans the junction region in which the proposed translational frameshift is thought to occur. Partial sequencing of this junction peptide confirms a -1 frameshift within the last few codons of 10A. C1 UNIV MED & DENT NEW JERSEY,DEPT MICROBIOL & MOLEC GENET,NEWARK,NJ 07103. BROOKHAVEN NATL LAB,UPTON,NY 11973. FU NCI NIH HHS [CA00890]; NIGMS NIH HHS [GM27711] NR 9 TC 15 Z9 15 U1 0 U2 0 PU COGNIZANT COMMUNICATION CORP PI ELMSFORD PA 3 HARTSDALE ROAD, ELMSFORD, NY 10523-3701 SN 1052-2166 J9 GENE EXPRESSION JI Gene Expr. PD MAY PY 1991 VL 1 IS 2 BP 127 EP 138 PG 12 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA FZ332 UT WOS:A1991FZ33200006 PM 1820210 ER PT J AU BRANDRIFF, B GORDON, L TRASK, B AF BRANDRIFF, B GORDON, L TRASK, B TI A NEW SYSTEM FOR HIGH-RESOLUTION DNA-SEQUENCE MAPPING IN INTERPHASE PRONUCLEI SO GENOMICS LA English DT Article ID INSITU HYBRIDIZATION; HUMAN-SPERM; HAMSTER; ORGANIZATION; LINE RP BRANDRIFF, B (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,POB 808,L-452,LIVERMORE,CA 94550, USA. NR 18 TC 53 Z9 53 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0888-7543 J9 GENOMICS JI Genomics PD MAY PY 1991 VL 10 IS 1 BP 75 EP 82 DI 10.1016/0888-7543(91)90486-X PG 8 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA FK408 UT WOS:A1991FK40800011 PM 2045112 ER PT J AU TAIT, CD JANECKY, DR ROGERS, PSZ AF TAIT, CD JANECKY, DR ROGERS, PSZ TI SPECIATION OF AQUEOUS PALLADIUM(II) CHLORIDE SOLUTIONS USING OPTICAL SPECTROSCOPIES SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID GROUP ELEMENT MINERALIZATION; HYDROTHERMAL SOLUTIONS; STILLWATER-COMPLEX; BUSHVELD COMPLEX; PLATINUM; SOLUBILITY; SULFIDE; SYSTEM; HYDROLYSIS; TRANSPORT AB Spectroscopic measurements of palladium(II) chloride solutions have been performed under ambient to elevated temperature conditions with systematic changes in pH and [Cl-]. Spectral signatures from electronic absorption spectra (Uv/Vis) and Raman vibrational spectra were determined, and these were subsequently used to systematically map out species along several paths of the predominance diagram. The species PdClx(H2O)4-x(2-x) (x = 2,3, or 4) and Pd(OH)2 were observed, along with a precipitation product formed from > 10-mu-M [Pd2+] solutions under near-neutral conditions. The elemental composition of the precipitation product was examined with a scanning electron micrograph (SEM) and was found to contain chloride as well as palladium. While sub-stoichiometric amounts of available OH- ligand produced UV/Vis solution spectra likely to be from mixed Pd-Cl-OH species, the pH field of these species would be vanishingly small at low, geologically relevant palladium ion concentrations where [OH-] is no longer the limiting reagent in the transformation. In mildly acidic media, where chloropalladium(II) species predominate, elevated temperatures (up to 90-degrees-C) cause lower charged palladium-chloride species to be favored, consistent with the lowered dielectric constant of water at higher temperatures. RP TAIT, CD (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,ISOTOPE GEOCHEM GRP INC-7,MAILSTOP J514,LOS ALAMOS,NM 87545, USA. NR 60 TC 48 Z9 48 U1 1 U2 18 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD MAY PY 1991 VL 55 IS 5 BP 1253 EP 1264 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FM716 UT WOS:A1991FM71600003 ER PT J AU PEARSON, MD SPANGLER, RR AF PEARSON, MD SPANGLER, RR TI CALIBRATION OF ALPHA-TRACK MONITORS FOR MEASUREMENT OF THORON (RN-220) SO HEALTH PHYSICS LA English DT Note ID RADON RP PEARSON, MD (reprint author), US DOE, CHEM NUCL GEOTECH INC, GRAND JUNCT PROJECTS OFF, POB 14000, GRAND JUNCTION, CO 81502 USA. NR 11 TC 11 Z9 13 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 MAY PY 1991 VL 60 IS 5 BP 697 EP 701 PG 5 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 FH807 UT WOS:A1991FH80700010 PM 2019502 ER PT J AU PHILLIPS, RL AF PHILLIPS, RL TI AN INTERPERSONAL MULTIMEDIA VISUALIZATION SYSTEM SO IEEE COMPUTER GRAPHICS AND APPLICATIONS LA English DT Article C1 UNIV MICHIGAN,ANN ARBOR,MI 48109. RP PHILLIPS, RL (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV COMP & COMMUN,COMP GRAPH GRP,POB 1663,MS B-272,LOS ALAMOS,NM 87545, USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 SN 0272-1716 J9 IEEE COMPUT GRAPH JI IEEE Comput. Graph. Appl. PD MAY PY 1991 VL 11 IS 3 BP 20 EP 27 DI 10.1109/38.79450 PG 8 WC Computer Science, Software Engineering SC Computer Science GA FL270 UT WOS:A1991FL27000009 ER PT J AU NIELSON, GM FOLEY, TA HAMANN, B LANE, D AF NIELSON, GM FOLEY, TA HAMANN, B LANE, D TI VISUALIZING AND MODELING SCATTERED MULTIVARIATE DATA SO IEEE COMPUTER GRAPHICS AND APPLICATIONS LA English DT Article C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP NIELSON, GM (reprint author), ARIZONA STATE UNIV,DEPT COMP SCI,TEMPE,AZ 85287, USA. NR 16 TC 40 Z9 46 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 SN 0272-1716 J9 IEEE COMPUT GRAPH JI IEEE Comput. Graph. Appl. PD MAY PY 1991 VL 11 IS 3 BP 47 EP 55 DI 10.1109/38.79453 PG 9 WC Computer Science, Software Engineering SC Computer Science GA FL270 UT WOS:A1991FL27000012 ER PT J AU BARNES, PR TESCHE, FM AF BARNES, PR TESCHE, FM TI ON THE DIRECT CALCULATION OF A TRANSIENT PLANE-WAVE REFLECTED FROM A FINITELY CONDUCTING HALF-SPACE SO IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY LA English DT Article AB This paper discusses an approach for computing the electromagnetic field reflected from a lossy half space directly in the time domain. This approach requires first evaluating the impulse response of the half space and then convolving it with the specified incident field waveform. To obtain the impulsive reflected field, either for vertical or horizontal polarization, approximations to the Fresnel reflection coefficients are made, thereby permitting an analytical expression in the time domain. Several different numerical examples using this technique are presented to illustrate the use of the method and the error contained in the solution. RP BARNES, PR (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 11 TC 62 Z9 68 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9375 J9 IEEE T ELECTROMAGN C JI IEEE Trans. Electromagn. Compat. PD MAY PY 1991 VL 33 IS 2 BP 90 EP 96 DI 10.1109/15.78345 PG 7 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA FF905 UT WOS:A1991FF90500002 ER PT J AU HANSEN, KM AF HANSEN, KM TI HEAD-BANGING - ROBUST SMOOTHING IN THE PLANE SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article ID LOCALLY WEIGHTED REGRESSION; STATISTICS; SPLINES; BUDGET AB The head-banging technique is a median-based smoother intended for use on nongridded spatial data. The smoother is designed to remove small-scale local variations within a data set, while preserving regional trends. Several synthetic and field data sets are used to test the performance of the technique. Head-banging is shown to be particularly adept at preserving edge structures, and is thus applicable in the field of structural geology, where data often contain edges due to faults or other steep formations. RP HANSEN, KM (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 24 TC 24 Z9 24 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 1991 VL 29 IS 3 BP 369 EP 378 DI 10.1109/36.79427 PG 10 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA FK385 UT WOS:A1991FK38500003 ER PT J AU SPANIAS, AS JONSSON, SB STEARNS, SD AF SPANIAS, AS JONSSON, SB STEARNS, SD TI TRANSFORM METHODS FOR SEISMIC DATA-COMPRESSION SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article AB This paper presents a study on seismic data compression. Our study concentrates on transform-based techniques. Transform coding algorithms are developed using the Discrete Fourier Transform (DFT), the Discrete Cosine Transform (DCT), the Walsh-Hadamard Transform (WHT), and the Karhunen-Loeve Transform (KLT). These are evaluated and compared to a linear predictive coding algorithm for data rates ranging from 150 to 550. Our results reveal that sinusoidal transforms are well suited for robust, low-rate seismic signal representation. In particular, it is shown that a DCT coding scheme reproduces faithfully the seismic waveform at approximately one-third of the original rate. In addition, the error introduced, by the latter coding scheme, in estimating the body wave magnitude (mb) [1] is negligible. C1 SANDIA NATL LABS,GROUND MOT & SEISM LAB,ALBUQUERQUE,NM 87185. RP SPANIAS, AS (reprint author), ARIZONA STATE UNIV,DEPT ELECT ENGN,TEMPE,AZ 85287, USA. NR 18 TC 15 Z9 15 U1 3 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 1991 VL 29 IS 3 BP 407 EP 416 DI 10.1109/36.79431 PG 10 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA FK385 UT WOS:A1991FK38500007 ER PT J AU MARNAY, C STRAUSS, T AF MARNAY, C STRAUSS, T TI EFFECTIVENESS OF ANTITHETIC SAMPLING AND STRATIFIED SAMPLING IN MONTE-CARLO CHRONOLOGICAL PRODUCTION COST MODELING SO IEEE TRANSACTIONS ON POWER SYSTEMS LA English DT Article; Proceedings Paper CT 1990 SUMMER MEETING OF THE POWER ENGINEERING SOC OF THE IEEE CY JUL 15-19, 1990 CL MINNEAPOLIS, MN SP IEEE, POWER ENGN SOC DE CONVERGENCE CRITERIA; LEAST-COST PLANNING; MARGINAL COST; MEAN AND VARIANCE OF PRODUCTION COST; PRODUCTION COSTING; SYSTEM PLANNING; VARIABLE OPERATING COST; VARIANCE REDUCTION AB Sampling error detracts from the usefulness of estimates of mean hourly marginal cost produced by Monte Carlo chronological production cost models. Variance reduction techniques commonly used in other Monte Carlo simulation applications can significantly improve the precision of estimates. Two such techniques, antithetic sampling and stratified sampling, are tested for a fictitious system. The number of iterations needed to reach a precision target falls significantly. The estimated savings in total computing time could exceed 50 percent for a full one-year forecast. Both techniques are easily implemented and should be used in Monte Carlo production costing efforts to estimate hourly marginal cost. C1 UNIV CALIF BERKELEY,IND ENGN & OPERAT RES,BERKELEY,CA 94720. RP MARNAY, C (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 20 TC 13 Z9 13 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0885-8950 J9 IEEE T POWER SYST JI IEEE Trans. Power Syst. PD MAY PY 1991 VL 6 IS 2 BP 669 EP 675 DI 10.1109/59.76711 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA FE859 UT WOS:A1991FE85900029 ER PT J AU KAHN, EP STOFT, S BERMAN, D GRAHAME, T AF KAHN, EP STOFT, S BERMAN, D GRAHAME, T TI OPTIMIZATION METHODS FOR EVALUATING COMPETITIVE BIDS FROM PRIVATE PRODUCERS SO IEEE TRANSACTIONS ON POWER SYSTEMS LA English DT Article; Proceedings Paper CT 1990 SUMMER MEETING OF THE POWER ENGINEERING SOC OF THE IEEE CY JUL 15-19, 1990 CL MINNEAPOLIS, MN SP IEEE, POWER ENGN SOC DE COMPETITIVE BIDDING; OPTIMIZATION; GENERATION EXPANSION; NONPRICE FACTORS AB Competitive bidding for private power contracts is becoming an important element in utility planning. This study examines the use of optimization methods for incoporating non-price factors into the evaluation process. Using data based on the 1988 Virginia Power solicitation and synthetic estimates of bids, the selection problem is simulated. The utility's announced preference for coal-fired projects is modeled using modifications to assumed fuel and capacity prices. Methodological issues for incorporating non-price factors in bid evaluation are discussed. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,ENERGY ANAL PROGRAM,BERKELEY,CA 94720. US DOE,OFF COAL TECHNOL,WASHINGTON,DC. RP KAHN, EP (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,UTIL POLICY & PLANNING GRP,BERKELEY,CA 94720, USA. NR 12 TC 7 Z9 8 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0885-8950 J9 IEEE T POWER SYST JI IEEE Trans. Power Syst. PD MAY PY 1991 VL 6 IS 2 BP 729 EP 735 DI 10.1109/59.76719 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA FE859 UT WOS:A1991FE85900037 ER PT J AU DEBOER, RJ AF DEBOER, RJ TI ALLELIC VARIATIONS OF HUMAN TCR V-GENE PRODUCTS SO IMMUNOLOGY TODAY LA English DT Letter ID REPERTOIRE; SELECTION RP DEBOER, RJ (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET MS K710,LOS ALAMOS,NM 87545, USA. RI De Boer, Rob/B-6050-2011 OI De Boer, Rob/0000-0002-2130-691X NR 11 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0167-5699 J9 IMMUNOL TODAY JI Immunol. Today PD MAY PY 1991 VL 12 IS 5 BP 169 EP 169 PG 1 WC Immunology SC Immunology GA FJ958 UT WOS:A1991FJ95800010 PM 1878129 ER PT J AU SHIPMAN, RWG DENN, MM KEUNINGS, R AF SHIPMAN, RWG DENN, MM KEUNINGS, R TI FREE-SURFACE EFFECTS IN TORSIONAL PARALLEL-PLATE RHEOMETRY SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID FLOWS AB Free-surface distortions caused by the combined effects of gravity and surface tension have little effect on the measured torque in torsional parallel-plate rheometry, but they can affect the measured normal stresses for dilute polymer solutions. A static free surface correction to the normal force is in good agreement with finite-element calculations and can be used to correct experimental measurements. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. NR 16 TC 14 Z9 14 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAY PY 1991 VL 30 IS 5 BP 918 EP 922 DI 10.1021/ie00053a014 PG 5 WC Engineering, Chemical SC Engineering GA FL089 UT WOS:A1991FL08900015 ER PT J AU POOLE, LJ KING, CJ AF POOLE, LJ KING, CJ TI REGENERATION OF CARBOXYLIC-ACID AMINE EXTRACTS BY BACK-EXTRACTION WITH AN AQUEOUS-SOLUTION OF A VOLATILE AMINE SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article AB Tertiary amines are effective extractants for the recovery of carboxylic acids from aqueous solution. An approach for regeneration and product recovery from such extracts is to back-extract the carboxylic acid with a water-soluble, volatile tertiary amine, such as trimethylamine. The resulting trimethylammonium carboxylate solution can be concentrated and thermally decomposed, yielding the product acid and the volatile amine for recycle. Equilibrium data are presented that show near-stoichiometric recovery of carboxylic acids from amine extracts. For fumaric and succinic acids, partial evaporation of the aqueous back-extract decomposes the carboxylate and yields the acid product in crystalline form. The decomposition of aqueous solutions of trimethylammonium lactates stops short of forming the acid product, because of its greater water solubility and tendency for self-association. Methods of further purifying the crystals are evaluated, along with processing implications of the results. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. NR 23 TC 42 Z9 42 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAY PY 1991 VL 30 IS 5 BP 923 EP 929 DI 10.1021/ie00053a015 PG 7 WC Engineering, Chemical SC Engineering GA FL089 UT WOS:A1991FL08900016 ER PT J AU TAYLOR, RP SCHRADER, GL AF TAYLOR, RP SCHRADER, GL TI LANTHANUM CATALYSTS FOR CH4 OXIDATIVE COUPLING - A COMPARISON OF THE REACTIVITY OF PHASES SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID METHANE; OXIDES; EARTH; ACTIVATION; CONVERSION; LA2O3; FUELS AB The catalytic performance of A-La2O3, La(OH)3, II-La2O2CO3, and La2(CO3)3 for the catalytic oxidative coupling of methane to C2 hydrocarbons was investigated over a range of reaction temperatures (up to 850-degrees-C). The activity of the starting materials for methane conversion and selectivity to ethylene and ethane were in the order II-La2O2CO3 > La2(CO3)3 > La(OH)3 > A-La2O3. Postreaction characterization by Fourier transform infrared spectroscopy and X-ray diffraction revealed that these materials undergo significant transformations. On the basis of this information, the presence of the oxycarbonate phase appears to have a beneficial effect on catalytic performance. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,DEPT CHEM ENGN,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. NR 26 TC 73 Z9 73 U1 5 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAY PY 1991 VL 30 IS 5 BP 1016 EP 1023 DI 10.1021/ie00053a025 PG 8 WC Engineering, Chemical SC Engineering GA FL089 UT WOS:A1991FL08900026 ER PT J AU BLOOMINGBURG, GF BAUER, JS CARTA, G BYERS, CH AF BLOOMINGBURG, GF BAUER, JS CARTA, G BYERS, CH TI CONTINUOUS SEPARATION OF PROTEINS BY ANNULAR CHROMATOGRAPHY SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article AB The separation of protein mixtures by continuous annular chromatography (CAC) is studied in a preparative-scale apparatus. S-Sepharose, a strong-acid porous cation-exchange resin is used as the separation medium, and mixtures of albumin, hemoglobin, and cytochrome c are used as a model separation system. Equilibrium and mass-transfer parameters are developed for this system on the basis of fixed-bed chromatograph experiments. A mathematical model is then successfully used in conjunction with these parameters to simulate the performance of the CAC separations. The continuous separation performance of the annular apparatus is found to be essentially the same as the batchwise performance of an equivalent conventional chromatograph, making the unit attractive for preparative and process-scale applications where continuous throughput is desirable. C1 UNIV VIRGINIA,DEPT CHEM ENGN,CHARLOTTESVILLE,VA 22903. OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831. NR 15 TC 40 Z9 40 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAY PY 1991 VL 30 IS 5 BP 1061 EP 1067 DI 10.1021/ie00053a031 PG 7 WC Engineering, Chemical SC Engineering GA FL089 UT WOS:A1991FL08900032 ER PT J AU BARKIGIA, KM MIURA, M THOMPSON, MA FAJER, J AF BARKIGIA, KM MIURA, M THOMPSON, MA FAJER, J TI MODELS OF PHOTOSYNTHETIC CHROMOPHORES - MOLECULAR-STRUCTURE OF THE BACTERIOCHLORIN (2,3,12,13-TETRAHYDRO-5,10,15,20-TETRAPHENYLPORPHINATO)(PYRIDINE)ZINC(II ) SO INORGANIC CHEMISTRY LA English DT Note ID DIFFERENTIAL-OVERLAP TECHNIQUE; INTERMEDIATE NEGLECT; RHODOPSEUDOMONAS-VIRIDIS; SPHAEROIDES R-26; OPTICAL-SPECTRA; CATION RADICALS; FREE BASE; SPECTROSCOPY; CRYSTAL; BACTERIOPHEOPHYTIN RP BARKIGIA, KM (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973, USA. NR 33 TC 38 Z9 38 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAY 1 PY 1991 VL 30 IS 9 BP 2233 EP 2236 DI 10.1021/ic00009a052 PG 4 WC Chemistry, Inorganic & Nuclear SC Chemistry GA FK180 UT WOS:A1991FK18000052 ER PT J AU MCCREERY, GE BANERJEE, S AF MCCREERY, GE BANERJEE, S TI PHASE-SEPARATION OF DISPERSED MIST AND DISPERSED ANNULAR (RIVULET OR THIN-FILM) FLOW IN A TEE .2. SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Article DE PHASE SEPARATION; TEE; DISPERSED MIST FLOW; DISPERSED ANNULAR FLOW ID PARTICLE AB An experimental and analytical investigation of dispersed mist and dispersed annular (rivulet or thin film) flow phase separation in a tee was performed. The analysis portion consisted of developing physically based models and incorporating the models into a computer program that calculates liquid drop and liquid pathline trajectories for these two flow regimes. Macroscopic mass balances were then calculated and compared with data. In addition, a correlation for dispersed mist phase separation was developed from computer calculations and is presented. C1 UNIV CALIF SANTA BARBARA,DEPT CHEM & NUCL ENGN,SANTA BARBARA,CA 93106. RP MCCREERY, GE (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415, USA. NR 25 TC 3 Z9 3 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD MAY-JUN PY 1991 VL 17 IS 3 BP 309 EP 325 DI 10.1016/0301-9322(91)90002-K PG 17 WC Mechanics SC Mechanics GA FP862 UT WOS:A1991FP86200002 ER PT J AU WAMBSGANSS, MW JENDRZEJCZYK, JA FRANCE, DM AF WAMBSGANSS, MW JENDRZEJCZYK, JA FRANCE, DM TI 2-PHASE FLOW PATTERNS AND TRANSITIONS IN A SMALL, HORIZONTAL, RECTANGULAR CHANNEL SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Article DE 2-PHASE FLOW; HORIZONTAL; RECTANGULAR; FLOW PATTERNS; TRANSITIONS ID GAS-LIQUID FLOW AB Horizontal two-phase flow was studied in a small cross-sectional-area (19.05 x 3.18 mm) rectangular channel with both the short and long sides forming the base, resulting in aspect ratios of 6 and 1/6, respectively. Adiabatic flows of air/water mixtures were tested over a large mass flux range (50-2000 kg/m2s). The full quality range was considered whenever experimentally achievable. Flow patterns were established and both mean and dynamic pressure measurements were used to accurately establish the plug/bubble-to-slug flow transition. This result, together with visual observations and supplemented with photographic data, was used to develop flow pattern maps. A comparison of existing flow pattern maps for circular pipes, capillary tubes and larger rectangular channels led to the conclusion that, while qualitative agreement exists, these maps are not generally applicable to the subject small rectangular channel on the quantitative basis. C1 UNIV ILLINOIS,DEPT MECH ENGN,CHICAGO,IL 60680. RP WAMBSGANSS, MW (reprint author), ARGONNE NATL LAB,DIV MAT & COMPONENTS TECHNOL,ARGONNE,IL 60439, USA. NR 20 TC 86 Z9 95 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD MAY-JUN PY 1991 VL 17 IS 3 BP 327 EP 342 DI 10.1016/0301-9322(91)90003-L PG 16 WC Mechanics SC Mechanics GA FP862 UT WOS:A1991FP86200003 ER PT J AU SHELDON, JW HARDY, KA KEHLER, P AF SHELDON, JW HARDY, KA KEHLER, P TI CONVECTIVE DIFFUSION OF A SOLUTE IN PIPE-FLOW SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Note C1 ARGONNE NATL LAB,ARGONNE,IL 60439. RP SHELDON, JW (reprint author), FLORIDA INT UNIV,DEPT PHYS,MIAMI,FL 33199, USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD MAY-JUN PY 1991 VL 17 IS 3 BP 415 EP 420 DI 10.1016/0301-9322(91)90008-Q PG 6 WC Mechanics SC Mechanics GA FP862 UT WOS:A1991FP86200008 ER PT J AU CHATTERJEE, A HOLLEY, WR AF CHATTERJEE, A HOLLEY, WR TI ENERGY DEPOSITION MECHANISMS AND BIOCHEMICAL ASPECTS OF DNA STRAND BREAKS BY IONIZING-RADIATION SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article ID HEAVY-PARTICLE TRACKS; IONS; CHEMISTRY; WATER AB A theoretical model based on physical, chemical, and biochemical mechanisms has been presented to evaluate the yields of DNA strand breaks (single and double) as a function of linear energy transfer (LET) or - dE/dx. Energetic heavy charged particles are considered explicitly to provide a general theory for low- as well as for high-LET rediation. There are three main features of the calculation: (a) track structure considerations for the energy deposition pattern, (b) three-dimensional structure of DNA molecules to provide information on the exact location of damage, and (c) a Monte-Carlo scheme to simulate the diffusion processes of water radicals. To avoid the complexities of a cellular medium, an aqueous solution of DNA is considered in the calculation. When the results of the calculations are compared with experimental measurements of the yields of strand breaks in mammalian DNA (exposed in a cellular complex), reasonable agreement is obtained. However, only those experimental data have been compared where there were no enzyme repair processes. The method of calculation has also been extended to study breaks in higher-order structures of DNA molecules such as chromatin. Specific limitations of the present model have been pointed out for making further improvements. RP CHATTERJEE, A (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV CELL & MOLEC BIOL,BERKELEY,CA 94720, USA. NR 30 TC 48 Z9 50 U1 2 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD MAY PY 1991 VL 39 IS 5 BP 709 EP 727 DI 10.1002/qua.560390508 PG 19 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA FG927 UT WOS:A1991FG92700007 ER PT J AU BANERJEE, A AF BANERJEE, A TI CONSTRUCTION OF ORTHOGONAL SUBSPACES SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article ID PAIRING THEOREM AB An orthogonalization procedure is presented that allows construction of at least (n - m) vectors orthogonal to {chi-j}, j = 1, m by linear combinations solely among {eta-i}, i = 1, n, n > m, and not-equal 0. An important application of the procedure is in effective core potential methods for which valence orbitals can be constructed that are orthogonal to the core orbitals and yet involve no component of the core. Thus, a separate calculation for only the valence electrons can be performed without any explicit reference to the core electrons (orbitals). C1 UNIV UTAH,DEPT CHEM,SALT LAKE CITY,UT 84112. RP BANERJEE, A (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,THEORET CHEM PROJECT,POB 1625,IDAHO FALLS,ID 83415, USA. NR 14 TC 2 Z9 2 U1 0 U2 3 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD MAY PY 1991 VL 39 IS 5 BP 747 EP 754 DI 10.1002/qua.560390510 PG 8 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA FG927 UT WOS:A1991FG92700009 ER PT J AU WOLOSCHAK, GE CHANGLIU, CM AF WOLOSCHAK, GE CHANGLIU, CM TI EXPRESSION OF CYTOSKELETAL ELEMENTS IN PROLIFERATING CELLS FOLLOWING RADIATION EXPOSURE SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID ACTIN GENE-EXPRESSION; IONIZING-RADIATION; MAMMALIAN-CELLS; DNA DAMAGE; NEOPLASTIC TRANSFORMATION; REPAIR PROCESSES; BETA-ACTIN; C-FOS; RNA; INDUCTION AB Previous work has demonstrated that radiation exposure modulates the expression of a series of genes, including those that encode cytoskeletal elements. The experiments reported here were designed to examine (1) the comparative effects of neutrons administered at high versus low dose-rates, (2) the comparative effects of neutrons on cycling versus resting cells and (3) the comparative effects of neutrons versus gamma-rays on beta- and gamma-actin mRNA accumulation in Syrian hamster embryo (SHE) cells 1 and 3 h post-irradiation. JANUS fission-spectrum neutrons from Argonne National Laboratory's JANUS reactor administered at high (12 cGy/min) dose-rates had little effect on resting cells, but at very low dose-rates (0.1 cGy/min) had a repressive effect on gamma-actin mRNA accumulation. Increased accumulation of beta-actin mRNA was detected following the exposure of cells to neutrons administered at high dose-rates, but repression of beta-actin mRNA was observed when neutrons were administered at low dose-rates. Cycling cells (unexposed and neutron irradiated) in all cases expressed higher levels of all actin-specific mRNAs than resting cells; beta-actin mRNA (but not gamma-actin mRNA) was induced to a greater extent in cycling cells than in resting cells during the first hour following neutron exposure. In resting cells, however, low dose-rate neutrons were more effective than low dose-rate gamma-rays at repressing both gamma- and beta-actin mRNA accumulation. These results demonstrate the differential effects of radiation quality (neutrons versus gamma-rays) and cell-cycle state on the modulation of actin isotype-specific gene expression. RP WOLOSCHAK, GE (reprint author), ARGONNE NATL LAB,DIV BIOL & MED RES,BIM-202,9700 S CASS AVE,ARGONNE,IL 60439, USA. RI Woloschak, Gayle/A-3799-2017 OI Woloschak, Gayle/0000-0001-9209-8954 NR 29 TC 29 Z9 29 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD MAY PY 1991 VL 59 IS 5 BP 1173 EP 1183 DI 10.1080/09553009114551051 PG 11 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA FT302 UT WOS:A1991FT30200006 PM 1675236 ER PT J AU STRADLING, GN GRAY, SA MOODY, JC HODGSON, A RAYMOND, KN DURBIN, PW RODGERS, SJ WHITE, DL TUROWSKI, PN AF STRADLING, GN GRAY, SA MOODY, JC HODGSON, A RAYMOND, KN DURBIN, PW RODGERS, SJ WHITE, DL TUROWSKI, PN TI THE EFFICACY OF DFO-HOPO, DTPA-DX AND DTPA FOR ENHANCING THE EXCRETION OF PLUTONIUM AND AMERICIUM FROM THE RAT SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID SEQUESTERING AGENTS; CHELATION-THERAPY; PURE LICAM(C); ACTINIDES; PU-238; MICE; LIGANDS; INHALATION; RETENTION; HAMSTERS AB A hydroxypridinone derivative of desferrioxamine (Na-DFO-HOPO), a dihydroxamic derivative of diethylenetriaminepenta-acetic acid (ZnNa-DTPA-DX), and DTPA (CaNa3- and ZnNa3-DTPA) were tested at dosages of 30-mu-mol kg-1 for their ability to remove Pu-238 or Am-241 from rats after their intravenous injection as citrate or inhalation as nitrate. The most effective treatment regimen for injected Pu was the repeated administration of DFO-HOPO; by 7 days the body content was reduced to 8% of that in untreated animals. Repeated dosages of 3-mu-mol kg-1 DFO-HOPO were as effective as those of 30-mu-mol kg-1 DTPA. After inhalation of Pu nitrate, repeated treatment with DTPA, DTPA-DX or DFO-HOPO reduced the body content by 7 days to, respectively, 10, 15 and 31% of those in untreated animals. After inhalation of Am, DTPA-DX and DTPA were equally effective, the body contents being reduced to 7% of control values with repeated treatment. Injection of DFO-HOPO was ineffective for enhancing the elimination of inhaled or injected Am. The results confirm the strategy of examining the use of siderophore analogues for the decorporation of Pu or Am. However, at present DTPA should remain the agent of choice, particularly after inhalation. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RP STRADLING, GN (reprint author), NATL RADIOL PROTECT BOARD,DIDCOT OX11 0RQ,OXON,ENGLAND. NR 22 TC 20 Z9 20 U1 1 U2 4 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD MAY PY 1991 VL 59 IS 5 BP 1269 EP 1277 DI 10.1080/09553009114551131 PG 9 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA FT302 UT WOS:A1991FT30200014 PM 1675243 ER PT J AU LONG, JCS KARASAKI, K DAVEY, A PETERSON, J LANDSFELD, M KEMENY, J MARTEL, S AF LONG, JCS KARASAKI, K DAVEY, A PETERSON, J LANDSFELD, M KEMENY, J MARTEL, S TI AN INVERSE APPROACH TO THE CONSTRUCTION OF FRACTURE HYDROLOGY MODELS CONDITIONED BY GEOPHYSICAL-DATA - AN EXAMPLE FROM THE VALIDATION EXERCISES AT THE STRIPA MINE SO INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES & GEOMECHANICS ABSTRACTS LA English DT Article ID FAULTS; ROCKS; ZONES AB One approach for the construction of fracture flow models is to collect statistical data about the geometry and hydraulic apertures of the fractures and use this data to construct statistically identical realizations of the fracture network for fluid flow analysis. We have found that this approach has two major problems. One is that an extremely small percentage of visible fractures may be hydrologically active. The other is that on any scale you are interested in characterizing usually a small number of large features dominate the behaviour ([1] Transport Processes in Porous Media. Kluwer Academic, The Netherlands, 1989). To overcome these problems we are proposing an approach in which the model is strongly conditioned by geology and geophysics. Tomography is used to identify the large features. The hydraulic behaviour of these features is then obtained using an inverse technique called "simulated annealing." The first application of this approach has been at the Stripa mine in Sweden as part of the Stripa Project. Within this effort, we built a model to predict the inflow to the Simulated Drift Experiment (SDE), i.e. inflow to six parallel, closely-spaced holes (two-holes), using a preliminary set of data collected in five other holes, the N- and W-holes. We predict a mean total flow of approx. 3.1 (1/min) into the six holes (two-holes) with a coefficient of variation near unity and a prediction error of about 4.61/min. The actual measured inflow is close to 21/min. RP LONG, JCS (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV EARTH SCI,BERKELEY,CA 94720, USA. NR 32 TC 36 Z9 37 U1 5 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0148-9062 J9 INT J ROCK MECH MIN JI Int. J. Rock Mech. Min. Sci. PD MAY PY 1991 VL 28 IS 2-3 BP 121 EP 142 DI 10.1016/0148-9062(91)92162-R PG 22 WC Engineering, Geological; Mining & Mineral Processing SC Engineering; Mining & Mineral Processing GA FH905 UT WOS:A1991FH90500001 ER PT J AU WARPINSKI, NR TEUFEL, LW AF WARPINSKI, NR TEUFEL, LW TI INSITU STRESS MEASUREMENTS AT RAINIER MESA, NEVADA TEST SITE - INFLUENCE OF TOPOGRAPHY AND LITHOLOGY ON THE STRESS STATE IN TUFF SO INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES & GEOMECHANICS ABSTRACTS LA English DT Article ID HYDRAULIC FRACTURE; UNITED-STATES; COLORADO; DEPTH; FIELD AB A large number of in situ stress measurements have been conducted in Rainier Mesa at the Nevada Test Site. Most of the measurements were made using the hydraulic fracture technique, but some comparisons with overcoring were also performed. Many of the hydraulic fractures were mined out and their behaviour was directly observed. The results show that horizontal in situ stresses in the mesa depend upon the depth, material properties, topography, bedding and faults. Large stress changes occur over distances much less than a metre, particularly near interfaces and faults. Bedding and topography were found to reorient stresses by as much as 45-degrees. This paper gives a case study of work at the Nevada Test Site and documents the variations in the stress field due to these geologic features. RP WARPINSKI, NR (reprint author), SANDIA NATL LABS,DIV GEOTECHNOL RES,ALBUQUERQUE,NM 87185, USA. NR 57 TC 19 Z9 20 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0148-9062 J9 INT J ROCK MECH MIN JI Int. J. Rock Mech. Min. Sci. PD MAY PY 1991 VL 28 IS 2-3 BP 143 EP 161 DI 10.1016/0148-9062(91)92163-S PG 19 WC Engineering, Geological; Mining & Mineral Processing SC Engineering; Mining & Mineral Processing GA FH905 UT WOS:A1991FH90500002 ER PT J AU REICH, CW AF REICH, CW TI AN INTERESTING FINDING IN TH-229 SO IZVESTIYA AKADEMII NAUK SSSR SERIYA FIZICHESKAYA LA Russian DT Article; Proceedings Paper CT 41ST CONF ON NUCLEAR SPECTROSCOPY AND ON THE NUCLEAR STRUCTURE CY APR, 1991 CL MINSK, USSR DE TH-229; CLOSELY SPACED LEVEL DOUBLET ID INTRINSIC REFLECTION ASYMMETRY; GAMMA-RAY; DECAY; STATES; U-233 RP REICH, CW (reprint author), IDAHO NATL ENGN LAB,IDAHO FALLS,ID, USA. NR 29 TC 1 Z9 1 U1 0 U2 0 PU MEZHDUNARODNAYA KNIGA PI MOSCOW PA 39 DIMITROVA UL., 113095 MOSCOW, RUSSIA SN 0367-6765 J9 IZV AN SSSR FIZ+ PD MAY PY 1991 VL 55 IS 5 BP 878 EP 886 PG 9 WC Physics, Multidisciplinary SC Physics GA GU316 UT WOS:A1991GU31600007 ER PT J AU CHOJNACKI, E GAI, W HO, C KONECNY, R MTINGWA, S NOREM, J ROSING, M SCHOESSOW, P SIMPSON, J AF CHOJNACKI, E GAI, W HO, C KONECNY, R MTINGWA, S NOREM, J ROSING, M SCHOESSOW, P SIMPSON, J TI MEASUREMENT OF DEFLECTION-MODE DAMPING IN AN ACCELERATING STRUCTURE SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB We have directly measured the damping of wake-field deflection modes in a slow-wave accelerating structure consisting of a dielectric-lined waveguide with segmented conducting boundaries wrapped with rf absorbing material. Such damping of deflection modes is desired to prevent beam breakup instabilities. Attenuation e-folding times of 246 ps were recorded for deflection modes at the Advanced Accelerator Test Facility while the quality of the desired accelerating mode remained unaffected. RP CHOJNACKI, E (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 9 TC 32 Z9 32 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1991 VL 69 IS 9 BP 6257 EP 6260 DI 10.1063/1.348823 PG 4 WC Physics, Applied SC Physics GA FM171 UT WOS:A1991FM17100004 ER PT J AU RICHARDSON, RA DENAVIT, J DICAPUA, MS RAMBO, PW AF RICHARDSON, RA DENAVIT, J DICAPUA, MS RAMBO, PW TI TRANSPORT OF RELATIVISTIC ELECTRON-BEAMS ALONG WIRE ARRAYS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID PROPAGATION; PLASMA AB Theoretical prediction and particle simulations indicate that an array of longitudinal wires will allow electron beam propagation, without an external guiding magnetic field and above the drift tube limit, by providing a charge and current neutralizing background. This paper presents experimental tests of this transport concept by injecting a 60 ns, 18 kA pulse of 1.4 MeV electrons into an array of 1-m long wires with a 1 cm spacing, filling a hexagon with 8.7-cm average radius. Arrays were tested with wires of varying resistances and diameters ranging from 12 to 1.3 mil. Transport was tested with wires terminating on a common conducting beam collector and with wires terminating on individually insulated beam collectors. The data show good transport (up to 90% of injected current) without significant energy loss, for wire diameters 3 mil or less, while transport is cutoff after 10 ns when 12 mil wires are used. Particle simulations show that this cutoff is due to an instability fed by excess return current resulting from electron scattering by the wires. The arrays terminated on individually insulated beam collectors showed better transported beam profiles, with less pinching, than the arrays with a common conducting beam collector. Particle simulations also correlate well with this result and provide an understanding of the effect of scattering on transport and beam quality. RP RICHARDSON, RA (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 15 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1991 VL 69 IS 9 BP 6261 EP 6272 DI 10.1063/1.348824 PG 12 WC Physics, Applied SC Physics GA FM171 UT WOS:A1991FM17100005 ER PT J AU HUGHES, RC ZIPPERIAN, TE DAWSON, LR BIEFELD, RM WALKO, RJ DVORACK, MA AF HUGHES, RC ZIPPERIAN, TE DAWSON, LR BIEFELD, RM WALKO, RJ DVORACK, MA TI GALLIUM-PHOSPHIDE JUNCTIONS WITH LOW LEAKAGE FOR ENERGY-CONVERSION AND NEAR ULTRAVIOLET DETECTORS SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB There is a need for semiconductor junctions with very low leakage for energy conversion from low level radioactive or radio-luminescent sources, and low noise blue-green photodiodes. We report the properties of two types of GaP junctions; a Schottky barrier of Pd on liquid phase epitaxy grown n-type GaP and a p+ over n junction grown by metal-organic chemical vapor deposition. Both types of junctions show very low leakage currents and good efficiency for power conversion from low level beta particles, x rays, and blue-green light. RP HUGHES, RC (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 14 TC 19 Z9 19 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1991 VL 69 IS 9 BP 6500 EP 6505 DI 10.1063/1.348858 PG 6 WC Physics, Applied SC Physics GA FM171 UT WOS:A1991FM17100040 ER PT J AU FEENSTRA, R LINDEMER, TB BUDAI, JD GALLOWAY, MD AF FEENSTRA, R LINDEMER, TB BUDAI, JD GALLOWAY, MD TI EFFECT OF OXYGEN-PRESSURE ON THE SYNTHESIS OF YBA2CU3O7-X THIN-FILMS BY POSTDEPOSITION ANNEALING SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CU-O FILMS; HIGH-TEMPERATURE SUPERCONDUCTORS; ORDERED-DEFECT STRUCTURE; CRITICAL CURRENTS; LIQUIDUS RELATIONS; EPITAXIAL-GROWTH; SINGLE-CRYSTALS; PHASE-DIAGRAMS; INSITU; STABILITY AB The effect of ambient oxygen pressure on the synthesis of epitaxial YBa2Cu3O7-x films on (100) SrTiO3 substrates by post-deposition annealing of amorphous precursor films was studied for oxygen partial pressures p(o2) between 1.0 and 8.0 x 10(-5) atm and annealing temperatures between 890 and 650-degrees-C. A p(o2) - 1/T diagram containing recent literature data regarding YBa2Cu3O7-x oxygen stoichiometry, phase stability, and liquid-phase formation was compiled to provide guidance for the selection and interpretation of annealing conditions. The results evidence a strong dependency of growth properties on the oxygen pressure with enhanced c-oriented epitaxy at lower p(o2) values. A particularly interesting result is the formation of predominantly c-oriented films at 740-degrees-C and p(o2) = 2.6 x 10(-4) atm (0.2 Torr). Similar to YBa2Cu3O7-x films produced by in situ laser ablation at the same temperature and oxygen pressure, the films exhibited low ion channeling yields (chi-min < 0.1) and a dense (smooth) surface morphology, while critical currents at 77 K were well in excess of 1 MA/cm2. From the observed systematic variation of structural film properties with synthesis conditions, annealing lines were derived indicating (T-p(o2)) combinations for either c- or a-oriented epitaxial growth. A comparison is made between these lines and synthesis conditions for in situ film growth as compiled recently by Hammond and Bormann [Physica C 162-169, 703 (1989)]. RP FEENSTRA, R (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. RI Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 99 TC 223 Z9 226 U1 2 U2 21 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1991 VL 69 IS 9 BP 6569 EP 6585 DI 10.1063/1.348868 PG 17 WC Physics, Applied SC Physics GA FM171 UT WOS:A1991FM17100050 ER PT J AU ASOKAKUMAR, P LYNN, KG LEUNG, TC NIELSEN, B WU, XY AF ASOKAKUMAR, P LYNN, KG LEUNG, TC NIELSEN, B WU, XY TI STUDY OF HYDROGEN INTERACTION WITH SIO2/SI(100) SYSTEM USING POSITRONS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INTERFACE; DEFECTS; BEAM AB We describe positron annihilation studies of SiO2/Si(100) structures having 100-nm-thick oxide grown by plasma enhanced chemical vapor deposition. A normalized shape parameter is used to characterize the positron annihilation spectra. Activation and passivation of interface states by atomic hydrogen are demonstrated by repeated vacuum anneal and atomic hydrogen exposure. Hydrogen activation energy is derived for one of the samples as epsilon = 2.02 +/- 0.07 eV. RP ASOKAKUMAR, P (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. RI Nielsen, Bent/B-7353-2009 OI Nielsen, Bent/0000-0001-7016-0040 NR 14 TC 11 Z9 11 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1991 VL 69 IS 9 BP 6603 EP 6606 DI 10.1063/1.348872 PG 4 WC Physics, Applied SC Physics GA FM171 UT WOS:A1991FM17100054 ER PT J AU MAHAN, AH CARAPELLA, J NELSON, BP CRANDALL, RS BALBERG, I AF MAHAN, AH CARAPELLA, J NELSON, BP CRANDALL, RS BALBERG, I TI DEPOSITION OF DEVICE QUALITY, LOW H CONTENT AMORPHOUS-SILICON SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CHEMICAL VAPOR-DEPOSITION; A-SI-H; DEFECT DENSITY; THIN-FILMS; MICROVOIDS; HYDROGEN AB Device-quality hydrogenated amorphous silicon containing as little as 1/10 the bonded H observed in device-quality glow discharge films have been deposited by thermal decomposition of silane on a heated filament. These low H content films show an Urbach edge width of 50 mV and a spin density of approximately 1/100 as large as that of glow discharge films containing comparable amounts of H. High substrate temperatures, deposition in a high flux of atomic H, and lack of energetic particle bombardment are suggested as reasons for this behavior. C1 HEBREW UNIV JERUSALEM,RACAH INST PHYS,IL-91904 JERUSALEM,ISRAEL. RP MAHAN, AH (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 29 TC 378 Z9 383 U1 6 U2 30 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1991 VL 69 IS 9 BP 6728 EP 6730 DI 10.1063/1.348897 PG 3 WC Physics, Applied SC Physics GA FM171 UT WOS:A1991FM17100081 ER PT J AU ANDERSON, SL MCINTOSH, L AF ANDERSON, SL MCINTOSH, L TI LIGHT-ACTIVATED HETEROTROPHIC GROWTH OF THE CYANOBACTERIUM SYNECHOCYSTIS SP STRAIN PCC-6803 - A BLUE-LIGHT-REQUIRING PROCESS SO JOURNAL OF BACTERIOLOGY LA English DT Article ID ALGA ANACYSTIS-NIDULANS; PHOTOSYSTEM-II; GREEN-ALGAE; GENETIC-ANALYSIS; MUTAGENESIS; CULTURES; SUBUNIT; INACTIVATION; CONSTRUCTION; TRANSCRIPTS AB A glucose-tolerant strain of Synechocystis sp. strain 6803 will not grow on glucose under complete darkness unless given a daily pulse of white light, typically 5 min of 40-mu-mol m-2 s-1 (light-pulsed conditions). The light pulse is insufficient for photoautotrophy, as glucose is required and growth yield is dependent on glucose concentration. Growth rate is independent of fluence, but growth yield is dependent on fluence, saturating at 40 to 75-mu-mol m-2 s-1. A Synechocystis strain 6803 psbA mutant strain grows under light-pulsed conditions at rates similar to those for the glucose-tolerant strain, indicating that photosystem II is not required for growth. The relative spectral sensitivity of the growth of light-pulsed cultures (growth only in blue light, 400 to 500 nm, maximum at 450 nm) precludes energetic contribution from cyclic electron transport around photosystem I. Pulses of long-wavelength light (i.e., 550 and 650 nm) did not support the growth of Synechocystis strain 6803 and, when supplied before or after a blue-light pulse, did not inhibit blue-light-stimulated growth of Synechocystis strain 6803. We conclude that the required blue-light pulse does not support growth via photosynthetic electron transport but appears instead to function as an environmental signal regulating heterotrophic metabolism, cell division, or other photomorphogenic processes. We have termed the growth of Synechocystis strain 6803 pulsed with light and kept otherwise in complete darkness light-activated heterotrophic growth. This observation of a blue-light requirement for the growth of Synechocystis strain 6803 represents a novel blue light effect on the growth of a cyanobacterium. C1 MICHIGAN STATE UNIV,US DOE,PLANT RES LAB,E LANSING,MI 48824. MICHIGAN STATE UNIV,DEPT BOT & PLANT PATHOL,E LANSING,MI 48824. MICHIGAN STATE UNIV,GENET PROGRAM,E LANSING,MI 48824. MICHIGAN STATE UNIV,DEPT BIOCHEM,E LANSING,MI 48824. NR 52 TC 187 Z9 196 U1 7 U2 23 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD MAY PY 1991 VL 173 IS 9 BP 2761 EP 2767 PG 7 WC Microbiology SC Microbiology GA FK038 UT WOS:A1991FK03800004 PM 1902208 ER PT J AU VANTOL, MFH QUINLAN, MA LUCK, F SOMORJAI, GA NIEUWENHUYS, BE AF VANTOL, MFH QUINLAN, MA LUCK, F SOMORJAI, GA NIEUWENHUYS, BE TI THE CATALYTIC REDUCTION OF NITRIC-OXIDE BY AMMONIA OVER A CLEAN AND VANADIUM OXIDE-COATED PLATINUM FOIL SO JOURNAL OF CATALYSIS LA English DT Article ID LOW CONCENTRATION MIXTURES; NH3; KINETICS; NO; MECHANISM; SPECTROSCOPY; NITROGEN C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT & CHEM SCI,CTR ADV MAT,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RHONE POULENC RECH,SERV CATALYSE,F-93308 AUBERVILLIERS,FRANCE. RP VANTOL, MFH (reprint author), LEIDEN STATE UNIV,GORLAEUS LABS,2300 RA LEIDEN,NETHERLANDS. NR 27 TC 8 Z9 8 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9517 J9 J CATAL JI J. Catal. PD MAY PY 1991 VL 129 IS 1 BP 186 EP 194 DI 10.1016/0021-9517(91)90022-V PG 9 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA FG050 UT WOS:A1991FG05000021 ER PT J AU SONNENBERG, A CALAFAT, J JANSSEN, H DAAMS, H VANDERRAAIJHELMER, LMH FALCIONI, R KENNEL, SJ APLIN, JD BAKER, J LOIZIDOU, M GARROD, D AF SONNENBERG, A CALAFAT, J JANSSEN, H DAAMS, H VANDERRAAIJHELMER, LMH FALCIONI, R KENNEL, SJ APLIN, JD BAKER, J LOIZIDOU, M GARROD, D TI INTEGRIN-ALPHA-6-BETA-4 COMPLEX IS LOCATED IN HEMIDESMOSOMES, SUGGESTING A MAJOR ROLE IN EPIDERMAL-CELL BASEMENT-MEMBRANE ADHESION SO JOURNAL OF CELL BIOLOGY LA English DT Article ID BULLOUS PEMPHIGOID ANTIGEN; MONOCLONAL-ANTIBODY; EPITHELIAL-CELLS; T-CELLS; EXTRACELLULAR-MATRIX; INTEGRIN RECEPTORS; SURFACE RECEPTORS; DESMOSOMAL PLAQUE; ALPHA-6 SUBUNIT; PROTEIN COMPLEX AB The alpha-6/beta-4 complex is a member of the integrin family of adhesion receptors. It is found on a variety of epithelial cell types, but is most strongly expressed on stratified squamous epithelia. Fluorescent antibody staining of human epidermis suggests that the beta-4 subunit is strongly localized to the basal region showing a similar distribution to that of the 230-kD bullous pemphigoid antigen. The alpha-6 subunit is also strongly localized to the basal region but in addition is present over the entire surfaces of basal cells and some cells in the immediate suprabasal region. By contrast staining for beta-1, alpha-2, and alpha-3 subunits was very weak basally, but strong on all other surfaces of basal epidermal cells. These results suggest that different integrin complexes play differing roles in cell-cell and cell-matrix adhesion in the epidermis. Immunoelectron microscopy showed that the alpha-6/beta-4 complex at the basal epidermal surface is strongly localized to hemidesmosomes. This result provides the first well-characterized monoclonal antibody markers for hemidesmosomes and suggests that the alpha-6/beta-4 complex plays a major role in epidermal cell-basement membrane adhesion. We suggest that the cytoplasmic domains of these transmembrane glycoproteins may contribute to the structure of hemidesmosomal plaques. Immunoultrastructural localization of the BP antigen suggests that it may be involved in bridging between hemidesmosomal plaques and keratin intermediate filaments of the cytoskeleton. C1 UNIV AMSTERDAM,EXPTL & CLIN IMMUNOL,AMSTERDAM,NETHERLANDS. NETHERLANDS CANC INST,DIV CELL BIOL,1066 CX AMSTERDAM,NETHERLANDS. NETHERLANDS CANC INST,DIV TUMOR BIOL,1066 CX AMSTERDAM,NETHERLANDS. IST REGINA ELENA,I-00161 ROME,ITALY. OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. UNIV MANCHESTER,DEPT OBSTET & GYNAECOL,MANCHESTER M13 9PL,LANCS,ENGLAND. UNIV MANCHESTER,DEPT BIOCHEM & MOLEC BIOL,MANCHESTER M13 9PL,LANCS,ENGLAND. UNIV MANCHESTER,MED ONCOL UNIT,CANC RES CAMPAIGN,MANCHESTER M13 9PL,LANCS,ENGLAND. UNIV MANCHESTER,DEPT SURG,MANCHESTER M13 9PL,LANCS,ENGLAND. RP SONNENBERG, A (reprint author), NETHERLANDS RED CROSS,BLOOD TRANSFUS SERV,CENT LAB,DEPT IMMUNOHAEMATOL,AMSTERDAM,NETHERLANDS. NR 67 TC 535 Z9 538 U1 0 U2 6 PU ROCKEFELLER UNIV PRESS PI NEW YORK PA 222 E 70TH STREET, NEW YORK, NY 10021 SN 0021-9525 J9 J CELL BIOL JI J. Cell Biol. PD MAY PY 1991 VL 113 IS 4 BP 907 EP 917 DI 10.1083/jcb.113.4.907 PG 11 WC Cell Biology SC Cell Biology GA FL988 UT WOS:A1991FL98800017 PM 2026654 ER PT J AU GOSNELL, TR TAYLOR, AJ LYMAN, JL AF GOSNELL, TR TAYLOR, AJ LYMAN, JL TI ULTRAFAST ABSORPTION-SPECTROSCOPY OF PHOTODISSOCIATED CF2BR2 - DETAILS OF THE REACTION-MECHANISM AND EVIDENCE FOR ANOMALOUSLY SLOW INTRAMOLECULAR VIBRATIONAL REDISTRIBUTION WITHIN THE CF2BR INTERMEDIATE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CROSS-SECTIONS; 248 NM; LASER; PHOTOPHYSICS; PHOTOLYSIS; SYSTEM AB Ultrafast time-resolved absorption spectroscopy in the hard ultraviolet has been used to investigate the photodissociation of gas-phase CF2Br2 photolyzed at 248 nm. The broadband spectra obtained in the 250-265 nm region have shown that absorption of a single photon activates a two-step sequential elimination of the molecule's two bromine atoms, leaving the product CF2 radical in the ground or first-excited vibrational state of its nu-2 bending mode. The spectra also demonstrate that direct detection of the vibrationally hot CF2Br intermediate species itself. We interpret the approximately 6 ps time scale over which the diffuse CF2Br spectrum evolves as evidence for slow intramolecular vibrational redistribution within this molecule. RP GOSNELL, TR (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV CHEM & LASER SCI,MS E543,LOS ALAMOS,NM 87545, USA. NR 18 TC 22 Z9 22 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1991 VL 94 IS 9 BP 5949 EP 5953 DI 10.1063/1.460429 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA FH765 UT WOS:A1991FH76500018 ER PT J AU PICKETT, TJ SHIRTS, RB AF PICKETT, TJ SHIRTS, RB TI SEMICLASSICAL QUANTIZATION OF VIBRATIONAL SYSTEMS USING FAST-FOURIER TRANSFORM METHODS - APPLICATION TO HDO STRETCHES SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MORSE SYSTEM; QUANTUM LOCALIZATION; OSCILLATOR-SYSTEMS; CLASSICAL CHAOS; ENERGY-SPECTRUM; STATISTICS; EIGENFUNCTIONS; EIGENVALUES; COUPLINGS; STABILITY AB Based on work by Martens and Ezra and partially developed independently by Eaker, we apply an improved method of approximating the quantum energy levels of a system of coupled oscillators using the fast-Fourier transform of classical coordinates and momenta to find quantizing trajectories. Application is made to a two-dimensional system modeling the stretching motions of the HDO molecule. The results are in excellent agreement with quantum calculations. This method is useful because: (1) it gives results which are independent of any separability of the Hamiltonian, (2) it is not limited in the number of degrees of freedom that can be handled, and (3) no zero-order approximation to the system is necessary. Results are equally valid inside and outside of resonance zones. RP PICKETT, TJ (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,CHEM SCI GRP,POB 1625,IDAHO FALLS,ID 83415, USA. NR 47 TC 9 Z9 9 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1991 VL 94 IS 9 BP 6036 EP 6046 DI 10.1063/1.460441 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA FH765 UT WOS:A1991FH76500031 ER PT J AU FEIGERLE, CS OVERBURY, SH HUNTLEY, DR AF FEIGERLE, CS OVERBURY, SH HUNTLEY, DR TI EFFECTS OF PREADSORBED OXYGEN ON THE BONDING AND DESORPTION-KINETICS OF CO ON NI(110) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ENERGY-LOSS SPECTROSCOPY; PRE-EXPONENTIAL FACTOR; CARBON-MONOXIDE; COVERAGE DEPENDENCE; ION-SCATTERING; SURFACE; ADSORPTION; PHOTOEMISSION; CHEMISORPTION; TRANSITIONS AB The effects of oxygen preadsorption on CO adsorption and CO desorption kinetics have been studied by temperature programmed desorption (TPD) and high resolution electron energy loss spectroscopy (HREELS). It is found that preadsorbed oxygen decreased total CO uptake at 120 K by no more than 20% even though the adsorption and desorption energies are strongly affected. The presence of oxygen causes several new desorption states to appear in the TPD whose populations depend sensitively upon oxygen predose. Using published results for the structure of oxygen covered Ni(110) and the present HREELS measurements, the desorption states have been assigned to structurally distinct bonding sites. Using the variation in heating rates method, the first order desorption energies and preexponential factors are obtained as a function of CO coverage for various oxygen predoses. The relationship between the desorption energies and the bonding sites, especially with regard to the distance of CO from neighboring oxygen atoms, is discussed. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP FEIGERLE, CS (reprint author), UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996, USA. RI Overbury, Steven/C-5108-2016 OI Overbury, Steven/0000-0002-5137-3961 NR 46 TC 9 Z9 9 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1991 VL 94 IS 9 BP 6264 EP 6273 DI 10.1063/1.460416 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA FH765 UT WOS:A1991FH76500059 ER PT J AU RARD, JA RAND, MH THORNBACK, JR WANNER, H AF RARD, JA RAND, MH THORNBACK, JR WANNER, H TI ON THE CORRECT ELECTRONIC GROUND-STATE OF TC(G) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Note ID POTENTIALS; TC-99 C1 HARWELL LAB,DIDCOT,OXON,ENGLAND. MEDGENIX,BRUSSELS,BELGIUM. ORG ECON COOPERAT & DEV,NUCL ENERGY AGCY,DATA BANK,GIF SUR YVETTE,FRANCE. RP RARD, JA (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DEPT EARTH SCI,LIVERMORE,CA 94550, USA. NR 21 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1991 VL 94 IS 9 BP 6336 EP 6337 DI 10.1063/1.460423 PG 2 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA FH765 UT WOS:A1991FH76500066 ER PT J AU JOHNSON, GK TASKER, IR JURGENS, R OHARE, PAG AF JOHNSON, GK TASKER, IR JURGENS, R OHARE, PAG TI THERMODYNAMIC STUDIES OF ZEOLITES - CLINOPTILOLITE SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article ID HEULANDITE RP JOHNSON, GK (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 20 TC 32 Z9 32 U1 0 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0021-9614 J9 J CHEM THERMODYN JI J. Chem. Thermodyn. PD MAY PY 1991 VL 23 IS 5 BP 475 EP 484 DI 10.1016/S0021-9614(05)80135-1 PG 10 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA FL213 UT WOS:A1991FL21300009 ER PT J AU BLACKWOOD, LG AF BLACKWOOD, LG TI THE QUALITY OF MEAN AND VARIANCE ESTIMATES FOR NORMAL AND LOGNORMAL DATA WHEN THE UNDERLYING DISTRIBUTION IS MISSPECIFIED SO JOURNAL OF CHEMOMETRICS LA English DT Article DE MEAN; VARIANCE; LOGNORMAL; OPTIMAL ESTIMATORS AB Theoretical and simulation results are employed to evaluate mean and variance estimates for normal data when a lognormal distribution is assumed and for lognormal data when a normal distribution is assumed. Misspecifying the distribution leads to the use of suboptimal estimation methods. However, the results show that the suboptimal methods still produce estimators of good quality (low bias and variance) relative to the minimum variance unbiased estimators for each distribution, at least when practical efficiency is considered. RP BLACKWOOD, LG (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,MEASUREMENT SYST ENGN,POB 1625,IDAHO FALLS,ID 83415, USA. NR 0 TC 6 Z9 7 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0886-9383 J9 J CHEMOMETR JI J. Chemometr. PD MAY PY 1991 VL 5 IS 3 BP 263 EP 271 DI 10.1002/cem.1180050313 PG 9 WC Automation & Control Systems; Chemistry, Analytical; Computer Science, Artificial Intelligence; Instruments & Instrumentation; Mathematics, Interdisciplinary Applications; Statistics & Probability SC Automation & Control Systems; Chemistry; Computer Science; Instruments & Instrumentation; Mathematics GA FQ606 UT WOS:A1991FQ60600012 ER PT J AU LEFORESTIER, C BISSELING, RH CERJAN, C FEIT, MD FRIESNER, R GULDBERG, A HAMMERICH, A JOLICARD, G KARRLEIN, W MEYER, HD LIPKIN, N RONCERO, O KOSLOFF, R AF LEFORESTIER, C BISSELING, RH CERJAN, C FEIT, MD FRIESNER, R GULDBERG, A HAMMERICH, A JOLICARD, G KARRLEIN, W MEYER, HD LIPKIN, N RONCERO, O KOSLOFF, R TI A COMPARISON OF DIFFERENT PROPAGATION SCHEMES FOR THE TIME-DEPENDENT SCHRODINGER-EQUATION SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID FOURIER METHOD SOLUTION; INDEX OPTICAL FIBERS; BEAM METHOD; MOLECULAR-DYNAMICS; MODE PROPERTIES; EIGENFUNCTIONS; COMPUTATION; DISPERSION; COLLISION C1 KONINKLIJKE SHELL EXPTL PROD LAB,1003 AA AMSTERDAM,NETHERLANDS. UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. UNIV TEXAS,DEPT CHEM,AUSTIN,TX 78712. INST CHEM,DK-2200 COPENHAGEN N,DENMARK. HEBREW UNIV JERUSALEM,DEPT PHYS CHEM,IL-91904 JERUSALEM,ISRAEL. HEBREW UNIV JERUSALEM,FRITZ HABER RES CTR MOLEC DYNAM,IL-91904 JERUSALEM,ISRAEL. UNIV BESANCON,PHYS MOLEC LAB,F-25030 BESANCON,FRANCE. INST PHYS CHEM,W-8700 WURZBURG,GERMANY. UNIV HEIDELBERG,INST PHYS CHEM,W-6900 HEIDELBERG,GERMANY. TECHNION ISRAEL INST TECHNOL,DEPT CHEM,IL-32000 HAIFA,ISRAEL. RP LEFORESTIER, C (reprint author), UNIV PARIS 11,CHIM THEOR LAB,CECAM WORKSHOP,F-91405 ORSAY,FRANCE. RI Meyer, Hans-Dieter/B-5611-2008; Feit, Michael/A-4480-2009; Kosloff, Ronnie/D-2388-2013; Roncero, Octavio/K-1872-2014 OI Meyer, Hans-Dieter/0000-0003-1365-0144; Kosloff, Ronnie/0000-0001-6201-2523; Roncero, Octavio/0000-0002-8871-4846 NR 32 TC 705 Z9 707 U1 4 U2 60 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAY PY 1991 VL 94 IS 1 BP 59 EP 80 DI 10.1016/0021-9991(91)90137-A PG 22 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA FK223 UT WOS:A1991FK22300003 ER PT J AU REIMAN, AH POMPHREY, N AF REIMAN, AH POMPHREY, N TI COMPUTATION OF MAGNETIC COORDINATES AND ACTION-ANGLE VARIABLES SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID HAMILTON-JACOBI EQUATION; FOURIER-TRANSFORM; NONSEPARABLE SYSTEMS; SEMICLASSICAL EIGENVALUES; VIBRATIONAL QUANTIZATION; POLYATOMIC-MOLECULES; BEHAVIOR RP REIMAN, AH (reprint author), PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. RI pomphrey, neil/G-4405-2010 NR 27 TC 19 Z9 19 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAY PY 1991 VL 94 IS 1 BP 225 EP 249 DI 10.1016/0021-9991(91)90144-A PG 25 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA FK223 UT WOS:A1991FK22300010 ER PT J AU BAMBERGER, CE ALLARD, LF COFFEY, DW BENNETT, MR AF BAMBERGER, CE ALLARD, LF COFFEY, DW BENNETT, MR TI WHISKERS OF TIN BY TOPOCHEMICAL REACTION SO JOURNAL OF CRYSTAL GROWTH LA English DT Article ID TITANIUM NITRIDE WHISKERS; CYANIDE AB It has been found that sodium titanate powder can be converted to TiN powder by treatment with gaseous ammonia at 1000-degrees-C. This observation has led to a test of the effect of ammonia on potassium titanate filaments. The result was a product which consisted of TiN filaments with essentially the same morphology as the starting titanate material. Examination of the filamentous material before and after the reaction (which we designated "topochemical") by scanning electron microscopy (SEM) and analytical transmission electron microscopy (TEM) confirmed that even single crystal filaments (whiskers) of K2Ti6O13 were topochemically converted to TiN whiskers. C1 OAK RIDGE NATL LAB,HIGH TEMP MAT LAB,OAK RIDGE,TN 37831. RP BAMBERGER, CE (reprint author), OAK RIDGE NATL LAB,DIV CHEM,POB 2008,OAK RIDGE,TN 37831, USA. NR 11 TC 3 Z9 3 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY PY 1991 VL 112 IS 1 BP 47 EP 54 DI 10.1016/0022-0248(91)90911-N PG 8 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA FQ320 UT WOS:A1991FQ32000007 ER PT J AU TSAO, JY BRENNAN, TM HAMMONS, BE AF TSAO, JY BRENNAN, TM HAMMONS, BE TI OSCILLATORY AS4 SURFACE-REACTION RATES DURING MOLECULAR-BEAM EPITAXY OF ALAS, GAAS AND INAS SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON MOLECULAR BEAM EPITAXY CY AUG 27-31, 1990 CL UNIV CALIF SAN DIEGO, LA JOLLA, CA HO UNIV CALIF SAN DIEGO ID ENERGY ELECTRON-DIFFRACTION; COMPUTER-SIMULATIONS; VICINAL SURFACES; GROWTH; REFLECTION; MBE; GAAS(001) AB We report oscillations in the surface reaction rate of As4 during molecular beam epitaxy of AlAs, GaAs and InAs. The oscillations are periodic with the bilayer-by-bilayer growth cycle, and correspond to a slightly lower reaction rate approximately 1/4 of the way, and a slightly higher reaction rate approximately 3/4 of the way, through that cycle. RP TSAO, JY (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 24 TC 12 Z9 12 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY PY 1991 VL 111 IS 1-4 BP 125 EP 130 DI 10.1016/0022-0248(91)90959-9 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA FT190 UT WOS:A1991FT19000023 ER PT J AU DODSON, BW AF DODSON, BW TI STRESS ACCOMMODATION IN LARGE-MISMATCH SYSTEMS SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON MOLECULAR BEAM EPITAXY CY AUG 27-31, 1990 CL UNIV CALIF SAN DIEGO, LA JOLLA, CA HO UNIV CALIF SAN DIEGO AB Accommodation of lattice mismatch is investigated for the case of large (epsilon > 0.02) mismatch. In particular, the regime where the separation D between misfit dislocations is much less than the strained layer thickness h is considered here. The conventional Matthews-Blakeslee mechanism for creation of misfit dislocations is found to be inadequate for the case of large lattice relaxation owing to interactions amongst the misfit dislocation at the interface. According to St. Venant's principle, the stress fields of the dislocation network are screened beyond a distance D from the dislocation cores. This observation has several consequences, including large densities of threading dislocations and the "melting" of moderately relaxed heterointerfaces at conventional semiconductor growth temperatures. A number of experimental observations may be explained via these models. RP DODSON, BW (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 7 TC 19 Z9 19 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY PY 1991 VL 111 IS 1-4 BP 376 EP 382 DI 10.1016/0022-0248(91)91004-T PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA FT190 UT WOS:A1991FT19000068 ER PT J AU KLEM, JF KURTZ, SR DATYE, A AF KLEM, JF KURTZ, SR DATYE, A TI GROWTH AND PROPERTIES OF GAASSB/INGAAS SUPERLATTICES ON INP SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON MOLECULAR BEAM EPITAXY CY AUG 27-31, 1990 CL UNIV CALIF SAN DIEGO, LA JOLLA, CA HO UNIV CALIF SAN DIEGO ID MOLECULAR-BEAM EPITAXY; GAAS0.5SB0.5; GAAS1-XSBX AB GaAsSb/InGaAs superlattices of varying thicknesses have been grown nominally lattice matched to InP and characterised by X-ray diffraction, transmission electron microscopy, Hall measurement, and photoluminescence. These structures exhibit net Hall electron densities of approximately 10(15) cm-3 at room temperature. X-ray diffraction results demonstrate the existence of an intrinsic interfacial strain between these two materials. Low-temperature photoluminescence in the range 2.3-2.8-mu-m is consistent with the expected type II band alignment in this system, and allows determination of the band offsets between these materials. C1 UNIV NEW MEXICO,DEPT CHEM & NUCL ENGN,ALBUQUERQUE,NM 87131. RP KLEM, JF (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. OI Datye, Abhaya/0000-0002-7126-8659 NR 11 TC 29 Z9 29 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY PY 1991 VL 111 IS 1-4 BP 628 EP 632 DI 10.1016/0022-0248(91)91053-D PG 5 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA FT190 UT WOS:A1991FT19000117 ER PT J AU FELICE, CW GAFFNEY, ES BROWN, JA AF FELICE, CW GAFFNEY, ES BROWN, JA TI EXTENDED SPLIT-HOPKINSON BAR ANALYSIS FOR ATTENUATING MATERIALS SO JOURNAL OF ENGINEERING MECHANICS LA English DT Article AB The standard split-Hopkinson bar data reduction procedure assumes uniform conditions exist over the length of the specimen allowing the average stress-strain response to be computed. When the stress wave enters the specimen, a gradient is established along its longitudinial axis. To use the standard analysis, approximately three wave transit times within the specimen are required to produce a condition of uniform stress. For attenuating materials, the time required to achieve stress uniformity can be considerable. This results in the loss of information on the behavior of the material, as the standard analysis will not be vaild during this time. Because soil is an attenuating medium, with a very low wave speed, stress uniformity is not achieved during the early portion of the experiment. Thus, in this region, the stress-strain response cannot be resolved by the standard analysis procedure. To resolve the early time response, a modified Lagrangian analysis procedure for reducing data in plane shock wave experiments has been used. By coupling the Lagrangian analysis procedure with the standard analysis procedure, a nearly complete description of the dynamic soil stress-strain response can be computed. To demonstrate the usefulness of this approach, experimental results on two soil types are presented. C1 KTECH CORP INC, ALBUQUERQUE, NM 87110 USA. UNIV CALIF LOS ALAMOS NAT LAB, LOS ALAMOS, NM 87595 USA. RP FELICE, CW (reprint author), TERRA TEK INC, 420 WAKARA WAY, SALT LAKE CITY, UT 84108 USA. NR 10 TC 6 Z9 6 U1 3 U2 3 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-9399 EI 1943-7889 J9 J ENG MECH JI J. Eng. Mech. PD MAY PY 1991 VL 117 IS 5 BP 1119 EP 1135 DI 10.1061/(ASCE)0733-9399(1991)117:5(1119) PG 17 WC Engineering, Mechanical SC Engineering GA FH767 UT WOS:A1991FH76700012 ER PT J AU CHEN, SS CHANDRA, S AF CHEN, SS CHANDRA, S TI FLUIDELASTIC INSTABILITIES IN TUBE BUNDLES EXPOSED TO NONUNIFORM CROSS-FLOW SO JOURNAL OF FLUIDS AND STRUCTURES LA English DT Article RP CHEN, SS (reprint author), ARGONNE NATL LAB,DIV MAT & COMPONENTS TECHNOL,ARGONNE,IL 60439, USA. NR 0 TC 8 Z9 8 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0889-9746 J9 J FLUID STRUCT JI J. Fluids Struct. PD MAY PY 1991 VL 5 IS 3 BP 299 EP 322 DI 10.1016/0889-9746(91)90497-D PG 24 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA FL591 UT WOS:A1991FL59100004 ER PT J AU MILLS, TR AF MILLS, TR TI DIRECT SYNTHESIS OF LIQUID-PHASE DIOXYGEN DIFLUORIDE SO JOURNAL OF FLUORINE CHEMISTRY LA English DT Article AB Dioxygen difluoride (O2F2) was produced directly in the liquid phase at temperatures above -154-degrees-C. An O2/F2 gas mixture was heated to 700-degrees-C and was then rapidly cooled on the outer surface of stainless steel tubes. The tubes were refrigerated by a liquid oxygen bath pressurized to > 7600 torr with helium. Six grams of O2F2 were produced in less than an hour. Color of the viscous liquid in the O2F2 generator ranged from copper red to straw yellow. Different O(x)F(y) compounds existed simultaneously on the tubes; explanations for this phenomenon are suggested. Audible ''pings'' and pressure excursions occurred when liquid O2F2 dripped onto uncooled portions of the apparatus. An orifice at the hot/cold interface was important in obtaining significant reaction rates. RP MILLS, TR (reprint author), LOS ALAMOS NATL LAB,DIV NUCL MAT TECHNOL,POB 1663,MAIL STOP E510,LOS ALAMOS,NM 87545, USA. NR 17 TC 5 Z9 5 U1 0 U2 7 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0022-1139 J9 J FLUORINE CHEM JI J. Fluor. Chem. PD MAY PY 1991 VL 52 IS 3 BP 267 EP 276 DI 10.1016/S0022-1139(00)80341-3 PG 10 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA FY907 UT WOS:A1991FY90700002 ER PT J AU BREWER, LM ALLEN, A AF BREWER, LM ALLEN, A TI N-FORMYL COCAINE - A STUDY OF COCAINE COMPARISON PARAMETERS SO JOURNAL OF FORENSIC SCIENCES LA English DT Article DE TOXICOLOGY; CRIMINALISTICS; COCAINE; DRUG IDENTIFICATION ID PERFORMANCE LIQUID-CHROMATOGRAPHY; CAPILLARY GAS-CHROMATOGRAPHY; MANUFACTURING BY-PRODUCTS; ILLICIT HEROIN; CIS-CINNAMOYLCOCAINE; OPIUM-ALKALOIDS; IMPURITIES; METHAMPHETAMINE; IDENTIFICATION; SAMPLES AB N-formyl cocaine has been found to be a processing impurity (via potassium permanganate oxidation) in clandestine cocaine processing. Chemical isolation and spectroscopic data are presented. Its occurrence in illicit cocaine samples is examined for its value in sample comparisons. A general discussion of clandestine cocaine processing and permanganate oxidation is included. C1 CALIF DEPT JUSTICE,SALINAS,CA. AMERICAN UNIV,WASHINGTON,DC 20016. DEA SE REG LAB,MIAMI,FL. RP BREWER, LM (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CALIF DEPT JUSTICE,DNA LAB,MS 934-47A,BERKELEY,CA 94720, USA. NR 45 TC 20 Z9 20 U1 1 U2 6 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD MAY PY 1991 VL 36 IS 3 BP 697 EP 707 PG 11 WC Medicine, Legal SC Legal Medicine GA FP610 UT WOS:A1991FP61000015 ER PT J AU MOORE, KR THOMAS, VA MCCOMAS, DJ AF MOORE, KR THOMAS, VA MCCOMAS, DJ TI GLOBAL HYBRID SIMULATION OF THE SOLAR-WIND INTERACTION WITH THE DAYSIDE OF VENUS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID GAS-DYNAMIC MODEL; BOW SHOCK; MACH NUMBER; ION PICKUP; PLASMA OBSERVATIONS; MAGNETIC-FIELD; MAGNETOSHEATH; LOCATION; MAGNETOTAIL; FLOW AB We present a 3-dimensional global hybrid simulation of the interaction of the solar wind with the entire dayside of Venus. The model obstacle is half the size of Venus, and planetary ion mass loading is included self-consistently. Results are compared to observations as well as to results from gasdynamic convected field modeling. Magnetic field magnitudes and bulk flow speeds along the planet-Sun line are comparable in both models, but only the hybrid model reproduces the experimentally observed magnetic barrier proton density depletions. The finite gyroradius of the planetary pickup ions causes a number density asymmetry in the direction of the convective (-V x B) electric field, as predicted and observed. Mass addition consistent with photoionization of the planetary neutral hot oxygen corona has little effect on the geometry of the shock, including the subsolar and terminator shock altitudes. Mass addition rates well in excess of likely values are required to significantly affect the model shock geometry. The hybrid model results imply that oxygen ions originating deep within the dayside Venus magnetic barrier are nearly fluidlike while oxygen ions produced higher on the dayside, at much lower densities, behave more as test particles. Gasdynamic modeling incorporating both fluid and test particle mass addition reproduces the O+ terminator escape flux (a few times 10(24) s-1) found in the hybrid model and inferred from observations, but underestimates the escape region spatial extent. The hybrid model predictions include a shock asymmetry dependent on the upstream IMF orientation, asymmetries in the magnetic barrier position and field magnitude, an asymmetry in pickup ion speed altitude profiles, and a finite gyroradius effect asymmetry in pickup ion number density caused by field draping. RP MOORE, KR (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,MS D438,LOS ALAMOS,NM 87545, USA. NR 45 TC 52 Z9 52 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1991 VL 96 IS A5 BP 7779 EP 7791 DI 10.1029/91JA00013 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FL029 UT WOS:A1991FL02900013 ER PT J AU RAHMAN, HU YUR, G WHITE, RS BIRN, J WESSEL, FJ AF RAHMAN, HU YUR, G WHITE, RS BIRN, J WESSEL, FJ TI ON THE INFLUENCE OF THE MAGNETIZATION OF A MODEL SOLAR-WIND ON A LABORATORY MAGNETOSPHERE SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID BIRKELAND CURRENT SYSTEM; FIELD-ALIGNED CURRENTS; POLAR-REGION; SIMULATION; PLASMA; TRIAD; CAP AB The interaction of a magnetized plasma beam with a stationary dipole field, analogous to the interaction of the solar wind with the Earth's magnetosphere, is explored in a laboratory experiment. Experimental parameters are chosen to scale qualitatively similar to the parameters in the Earth's magnetosphere. We find that the magnetization of the laboratory "solar wind," generated by injecting a plasma across a preexisting magnetic field, requires a certain minimum magnetic field strength. Differences between the resulting magnetospheres for northward and southward "solar wind" or "interplanetary" magnetic fields (IMF) are demonstrated by global pictures and by magnetic field measurements above the north polar region. These measurements show patterns of the variation of the transverse field component which are similar to those found by satellite measurements above the Earth. This indicates the presence of similar field-aligned current systems. We demonstrate particularly the presence (for northward IMF) and absence (for southward IMF) of the pattern attributed to the "NBZ" (northward B(Z)) current system. C1 UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. UNIV CALIF IRVINE,DEPT PHYS,IRVINE,CA 92717. RP RAHMAN, HU (reprint author), UNIV CALIF RIVERSIDE,INST GEOPHYS & PLANETARY PHYS,RIVERSIDE,CA 92521, USA. NR 23 TC 8 Z9 8 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1991 VL 96 IS A5 BP 7823 EP 7829 DI 10.1029/90JA01993 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FL029 UT WOS:A1991FL02900016 ER PT J AU GOSLING, JT MCCOMAS, DJ PHILLIPS, JL BAME, SJ AF GOSLING, JT MCCOMAS, DJ PHILLIPS, JL BAME, SJ TI GEOMAGNETIC-ACTIVITY ASSOCIATED WITH EARTH PASSAGE OF INTERPLANETARY SHOCK DISTURBANCES AND CORONAL MASS EJECTIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SOLAR-WIND; MAGNETIC STORMS; TRANSIENTS; ISEE-3; FIELDS; EVENTS; CLOUDS AB Coronal mass ejection events (CMEs) are important occasional sources of plasma and magnetic field in the solar wind at 1 AU, accounting for approximately 10% of all solar wind measurements in the ecliptic plane during the last solar activity maximum. Previous work indicates that virtually all transient shock wave disturbances in the solar wind are driven by fast CMEs. Using a recently appreciated capability for distinguishing CMEs in solar wind data in the form of counterstreaming solar wind electron events, this paper explores the overall effectiveness of shock wave disturbances and CMEs in general in stimulating geomagnetic activity. The study is confined to the interval from mid-August 1978 through mid-October 1982, spanning the last solar activity maximum, when ISEE 3 was in orbit about the L1 Lagrange point 220 R(e) upstream from Earth. We find that all but one of the 37 largest geomagnetic storms in that era were associated with Earth passage of CMEs and/or shock disturbances, with the large majority of these storms (27 out of 37) being associated with interplanetary events where Earth encountered both a shock and the CME driving the shock (shock/CME events). Although CMEs and/or shock disturbances were increasingly the cause of geomagnetic activity as the level of geomagnetic activity increased, many smaller geomagnetic disturbances were unrelated to these events. Further, approximately half of all CMEs and half of all shock disturbances encountered by Earth did not produce any substantial geomagnetic activity as measured by the planetary geomagnetic index Kp. The geomagnetic effectiveness of Earth directed CMEs and shock wave disturbances was directly related to the flow speed, the magnetic field magnitude, and the strength of the southward (GSM) field component associated with the events. The initial speed of a CME close to the Sun appears to be the most crucial factor in determining if an earthward directed event will be effective in exciting a large geomagnetic disturbance. RP UNIV CALIF LOS ALAMOS SCI LAB, MS D438, LOS ALAMOS, NM 87545 USA. NR 33 TC 377 Z9 390 U1 2 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1991 VL 96 IS A5 BP 7831 EP 7839 DI 10.1029/91JA00316 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FL029 UT WOS:A1991FL02900017 ER PT J AU QIAN, S HUDSON, MK ROTH, I AF QIAN, S HUDSON, MK ROTH, I TI PARTICLE SIMULATION OF ION HEATING IN THE RING CURRENT - REPLY SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Letter C1 DARTMOUTH COLL,DEPT PHYS & ASTRON,HANOVER,NH 03755. UNIV CALIF BERKELEY,SPACE SCI LAB,BERKELEY,CA 94720. RP QIAN, S (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545, USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1991 VL 96 IS A5 BP 7931 EP 7932 DI 10.1029/91JA00050 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FL029 UT WOS:A1991FL02900028 ER PT J AU REID, RS PATE, MB BERGLES, AE AF REID, RS PATE, MB BERGLES, AE TI A COMPARISON OF AUGMENTATION TECHNIQUES DURING IN-TUBE EVAPORATION OF R-113 SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article AB An experimental study was conducted to determine the potential of three techniques for augmenting in-tube evaporation of refrigerants: high-fin tubes, microfin tubes, and twisted tape inserts. Five tubes with internal fins and one smooth tube with a twisted-tape insert were tested. Additionally, experiments were performed with two reference smooth tubes having diameters similar to the maximum inside diameters of the finned tubes. All experiments involved evaporating Refrigerant 113 (R-113) by direct electrical heating of the tube wall. Local evaporation heat transfer coefficients were measured as a function of quality for a range of mass fluxes and heat fluxes. Enhancement factors were calculated by forming ratios of the heat transfer coefficient for the augmented tube and a smooth tube of the same maximum inside diameter. Mass fluxes, pressure levels, and qualities were fixed when enhancement factors were calculated. For the internally finned tubes the enhancement factors varied from 1.1 to 2.8. An internally finned tube having helical spiral angles of 16 deg produced the largest enhancement of heat transfer. The tube with the twisted-tape insert typically had an enhancement factor of about 1.5. Pressure gradient ratios and enhancement performance ratios are also presented. C1 UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87544. RENSSELAER POLYTECH INST,TROY,NY 12180. NR 15 TC 21 Z9 22 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD MAY PY 1991 VL 113 IS 2 BP 451 EP 458 DI 10.1115/1.2910582 PG 8 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA HP759 UT WOS:A1991HP75900025 ER PT J AU MAHAJAN, RL CHU, TY DICKINSON, DA AF MAHAJAN, RL CHU, TY DICKINSON, DA TI AN EXPERIMENTAL-STUDY OF LAMINAR-FILM CONDENSATION WITH STEFAN NUMBER GREATER THAN UNITY SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article AB Experimental laminar condensation heat transfer data are reported for fluids with Stefan number up to 3.5. The fluid used is a member of a family of fluorinated fluids, which have been used extensively in the electronics industry for soldering, cooling, and testing applications. Experiments were performed by suddenly immersing cold copper spheres in the saturated vapor of this fluid, and heat transfer rates were calculated using the quasi-steady temperature response of the spheres. In these experiments, the difference between saturation and wall temperature varied from 0.5-degrees-C to 190-degrees-C. Over this range of temperature difference, the condensate properties vary significantly; viscosity of the condensate varies by a factor of nearly 50. Corrections for the temperature-dependent properties of the condensate therefore were incorporated in calculating the Nusselt number based on the average heat transfer coefficient. The results are discussed in light of past experimental data and theory for Stefan number less than unity. To the knowledge of the authors, this is the first reported study of condensation heat transfer examining the effects of Stefan number greater than unity. C1 AT&T BELL LABS,PRINCETON,NJ 08540. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. NR 25 TC 1 Z9 1 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD MAY PY 1991 VL 113 IS 2 BP 472 EP 478 DI 10.1115/1.2910585 PG 7 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA HP759 UT WOS:A1991HP75900028 ER PT J AU KOTSUBO, V SWIFT, GW AF KOTSUBO, V SWIFT, GW TI SUPERFLUID STIRLING-CYCLE REFRIGERATION BELOW 1-KELVIN SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article ID HE-3-HE-4 MIXTURES AB A new method for cooling below 1 K, the superfluid Stirling cycle, uses the gaslike thermodynamic properties of the He-3 solute in a superfluid He-3-He-4 solution. The first prototype superfluid Stirling-cycle refrigerator cools to 0.6 K from a starting temperature of 1.2 K, with cooling powers at the lowest temperatures of a few tens of microwatts. The cycle works in both classical-gas and Fermi-gas regimes. RP KOTSUBO, V (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,CONDENSED MATTER & THERMAL PHYS GRP,LOS ALAMOS,NM 87544, USA. NR 14 TC 13 Z9 13 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 1991 VL 83 IS 3-4 BP 217 EP 224 DI 10.1007/BF00682119 PG 8 WC Physics, Applied; Physics, Condensed Matter SC Physics GA FT041 UT WOS:A1991FT04100006 ER PT J AU PAN, HJ GERSTEIN, BC AF PAN, HJ GERSTEIN, BC TI NMR OF P-31 IN (VO)2P2O7 AS AN INTERNAL TEMPERATURE STANDARD IN HIGH-TEMPERATURE NMR SO JOURNAL OF MAGNETIC RESONANCE LA English DT Note C1 IOWA STATE UNIV SCI & TECHNOL,INST PHYS RES & TECHNOL,AMES,IA 50011. RP PAN, HJ (reprint author), IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011, USA. NR 4 TC 17 Z9 18 U1 1 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2364 J9 J MAGN RESON PD MAY PY 1991 VL 92 IS 3 BP 618 EP 619 DI 10.1016/0022-2364(91)90358-Z PG 2 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA FJ100 UT WOS:A1991FJ10000017 ER PT J AU MUELLER, KT WOOTEN, EW PINES, A AF MUELLER, KT WOOTEN, EW PINES, A TI PURE-ABSORPTION-PHASE DYNAMIC-ANGLE SPINNING SO JOURNAL OF MAGNETIC RESONANCE LA English DT Note ID DIMENSIONAL CORRELATED SPECTROSCOPY; NMR; SPECTRA; SOLIDS; NUCLEI C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT SCI,1 CYCLOTRON RD,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RI Mueller, Karl/A-3637-2010 NR 15 TC 31 Z9 31 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2364 J9 J MAGN RESON PD MAY PY 1991 VL 92 IS 3 BP 620 EP 627 DI 10.1016/0022-2364(91)90359-2 PG 8 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA FJ100 UT WOS:A1991FJ10000018 ER PT J AU HOLMES, DJ AF HOLMES, DJ TI SOCIAL-BEHAVIOR IN CAPTIVE VIRGINIA OPOSSUMS, DIDELPHIS-VIRGINIANA SO JOURNAL OF MAMMALOGY LA English DT Article ID MOVEMENT PATTERNS; COMMON OPOSSUM; DOMINANCE; MARSUPIALIS AB To examine social behavior in Virginia opossums (Didelphis virginiana) systematically, spontaneous interactions and nesting behavior of three mixed-sex groups of adults were observed in a seminatural setting during a 7-month period including segments of breeding and nonbreeding seasons. Interactions were predominantly affiliative or nonagonistic, and nestling associations also indicated a greater capacity for social tolerance than generally is recongnized for didelphid marsupials. The overall frequency of social interactions peaked with onset of breeding in January, and intrasexual agonistic encounters (primarily female-female) occurred more often than male-female encounters. Opossums readily formed stable linear-dominance hierarchies, with females usually dominant. These data suggest that opossum sociality is better developed than generally recognized, and that seasonal influences should be considered when assessing social complexity in this species. C1 BOWLING GREEN STATE UNIV,DEPT BIOL SCI,BOWLING GREEN,OH 43403. SAVANNAH RIVER ECOL LAB,AIKEN,SC 29802. NR 49 TC 8 Z9 9 U1 0 U2 2 PU AMER SOC MAMMALOGISTS PI PROVO PA BRIGHAM YOUNG UNIV, DEPT OF ZOOLOGY, PROVO, UT 84602 SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD MAY PY 1991 VL 72 IS 2 BP 402 EP 410 DI 10.2307/1382114 PG 9 WC Zoology SC Zoology GA FN196 UT WOS:A1991FN19600021 ER PT J AU GARZON, FH RAISTRICK, ID GINLEY, DS HALLORAN, JW AF GARZON, FH RAISTRICK, ID GINLEY, DS HALLORAN, JW TI THERMODYNAMIC INSTABILITY OF THE YBA2CU3O7-X PHASE AT THE 1-2-3 COMPOSITION SO JOURNAL OF MATERIALS RESEARCH LA English DT Note ID SUPERCONDUCTORS; YBA2CU4O8 AB We have measured enthalpies of formation of YBa2Cu3O7-x, Y2BaCuO5, YBa2Cu4O8, and BaCuO2 using high precision isothermal solution calorimetry. Thermodynamic analysis of the calorimetric data indicates that YBa2Cu3O7-x at the pure-phase composition (1:2:3 cation ratio) is metastable at congruent-to 873 K and 1 atm P(O)2. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. CPS SUPERCOND CORP,MILFORD,MA 01757. RP GARZON, FH (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. RI Halloran, John /G-9210-2011; OI Halloran, John/0000-0002-1913-6886 NR 11 TC 24 Z9 24 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1991 VL 6 IS 5 BP 885 EP 887 DI 10.1557/JMR.1991.0885 PG 3 WC Materials Science, Multidisciplinary SC Materials Science GA FK039 UT WOS:A1991FK03900001 ER PT J AU HEALD, SM BARRERA, EV AF HEALD, SM BARRERA, EV TI GLANCING ANGLE X-RAY STUDY OF THE EFFECT OF OXYGEN ON INTERFACE REACTIONS IN AL/NI BILAYERS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID ABSORPTION FINE-STRUCTURE; REFLECTIVITY AB Glancing angle x-ray reflectivity and EXAFS measurements have been made on a series of UHV prepared Al/Ni bilayers with varying amounts of oxygen impurities. These samples show an intrinsic reacted region prior to annealing, and for clean samples further reaction occurs at 250-degrees-C. Oxygen is found to influence strongly the course of the reaction with an effect which depends on its location. A few percent O impurity within the Al film strongly suppresses the grain boundary diffusion path, which allows the growth of a smooth NiAl3 layer. Interfacial O exposures of 60 and 600 Langmuir both inhibit the initial reaction and raise the temperature at which further reaction occurs to as much as 300-degrees-C with an effect which depends on exposure. The thickness of the intrinsic reaction zone is about 60 angstrom for clean samples, and is nearly eliminated for contaminated interfaces. The results indicate that surface/interface, grain boundary, and bulk diffusion all play important roles in the formation of these interfaces, and that each of these is influenced by O impurities. RP HEALD, SM (reprint author), BROOKHAVEN NATL LAB,DIV APPL PHYS,UPTON,NY 11973, USA. NR 17 TC 14 Z9 14 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1991 VL 6 IS 5 BP 935 EP 942 DI 10.1557/JMR.1991.0935 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA FK039 UT WOS:A1991FK03900008 ER PT J AU NAJAFABADI, R SROLOVITZ, DJ LESAR, R AF NAJAFABADI, R SROLOVITZ, DJ LESAR, R TI THERMODYNAMIC AND STRUCTURAL-PROPERTIES OF [001] TWIST BOUNDARIES IN GOLD SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID X-RAY-DIFFRACTION; GRAIN-BOUNDARY; COMPUTER-SIMULATION; MOLECULAR-DYNAMICS; ATOMIC-STRUCTURE; FREE-ENERGY; PHASE-TRANSITION; FCC METALS; TEMPERATURE; NI AB We have employed the Local Harmonic (LH) model and the Embedded Atom Method (EAM) to examine the structural and thermodynamic properties of a series of twelve [001] twist boundaries in gold for temperatures between 0 k and 700 K. For the majority of the grain boundary misorientations, metastable structures were observed with grain boundary energies that were typically less than 0.1% larger than the stable structures. Four of the twelve grain boundaries underwent first order structural phase transitions as seen by the crossing of the free energy versus temperature curves for the competing structures. Relatively small cusps or inflections in the grain boundary free energy versus misorientation curves were observed at SIGMA-5 (36.87-degrees) and SIGMA-13 (22.62-degrees) at low temperatures, at SIGMA-13 (22.62-degrees) and SIGMA-17 (28.07-degrees) at intermediate temperatures, and at SIGMA-5 (36.87-degrees) and SIGMA-17 (28.07-degrees) at elevated temperatures. A maximum in the grain boundary entropy versus misorientation was observed at SIGMA-17 (28.07-degrees) for all temperatures, and local minima were observed at SIGMA-5 (36.87-degrees) at low temperature and in SIGMA-13 (22.62-degrees) at high temperature. The excess volume associated with the grain boundary shows a roughly linear dependence on grain boundary free energy at each temperature examined. The room-temperature mean-square vibrational amplitude is approximately 25% larger than that for the bulk at the (002) plane adjacent to the boundary and decays to within 2% of the bulk value by the second (002) plane from the boundary. The room-temperature mean-square vibrational amplitude is dominated by the in-plane (parallel to the grain boundary) vibrations at the (002) plane nearest the grain boundary. C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP NAJAFABADI, R (reprint author), UNIV MICHIGAN,DEPT MAT SCI & ENGN,ANN ARBOR,MI 48109, USA. RI LeSar, Richard/G-1609-2012 NR 29 TC 34 Z9 34 U1 3 U2 11 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1991 VL 6 IS 5 BP 999 EP 1011 DI 10.1557/JMR.1991.0999 PG 13 WC Materials Science, Multidisciplinary SC Materials Science GA FK039 UT WOS:A1991FK03900015 ER PT J AU NIEMAN, GW WEERTMAN, JR SIEGEL, RW AF NIEMAN, GW WEERTMAN, JR SIEGEL, RW TI MECHANICAL-BEHAVIOR OF NANOCRYSTALLINE CU AND PD SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID SIZED CRYSTALLINE MATERIALS; NANOPHASE TIO2; GRAIN-SIZE; SPECTROSCOPY; DEPENDENCE; STRAIN AB This report gives results of a study of the bulk mechanical properties of samples of nanocrystalline Cu and Pd consolidated from powders prepared by inert gas condensation. Fourier analysis x-ray diffraction techniques, used to determine average grain size and mean lattice strains of the as-consolidated samples, show grain sizes in the range of 3-50 nm and lattice strains ranging from 0.02-3%. Sample densities range from 97-72% of the density of a coarse-grained standard. Microhardness of the nanocrystalline samples exceeds that of annealed, coarse-grained samples by a factor of 2-5, despite indications that sample porosity reduces hardness values below the ultimate value. Uniaxial tensile strength of the nanocrystalline samples is similarly elevated above the value of the coarse-grained standard samples. Restrictions on dislocation generation and mobility imposed by ultrafine grain size are believed to be the dominant factor in raising strength. Residual stress may also play a role. Room temperature diffusional creep, predicted to be appreciable in nanocrystalline samples, was not found. Instead, samples appear to show logarithmic creep that is much smaller than the predicted Coble creep. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP NIEMAN, GW (reprint author), NORTHWESTERN UNIV,DEPT MAT SCI & ENGN,EVANSTON,IL 60208, USA. RI Weertman, Julia/B-7540-2009 NR 52 TC 400 Z9 412 U1 7 U2 53 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1991 VL 6 IS 5 BP 1012 EP 1027 DI 10.1557/JMR.1991.1012 PG 16 WC Materials Science, Multidisciplinary SC Materials Science GA FK039 UT WOS:A1991FK03900016 ER PT J AU DUNMEAD, SD MUNIR, ZA HOLT, JB KINGMAN, DD AF DUNMEAD, SD MUNIR, ZA HOLT, JB KINGMAN, DD TI SIMULTANEOUS SYNTHESIS AND DENSIFICATION OF TIC/NI-AL COMPOSITES SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID COMBUSTION SYNTHESIS; TITANIUM CARBIDE; PRESSURE AB The process of combustion synthesis was used to produce ceramic-metal composite materials consisting of titanium carbide (TiC) and an intermetallic alloy of the Ni-Al system. The samples were produced by rapidly heating a mixture of elemental Ti, C, Ni, and Al powders in a graphite die up to the ignition temperature. By applying mechanical pressure during or immediately following the combustion reaction, products of greater than 99% theoretical density were obtained. The residual porosity and microstructural development were characterized using optical microscopy, and X-ray diffraction methods. The nature and composition of the product phases can be controlled by variations in the ratios of the starting reagents, level of mechanical pressure, addition of diluents, and the inclusion of dopants. By varying the combustion synthesis parameters, the properties of the product can be tailored to meet specific application needs. Apparent applications of such composites include cutting tools, wear parts, structural components, armour, etc. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,LIVERMORE,CA 94550. RP DUNMEAD, SD (reprint author), UNIV CALIF DAVIS,DIV MAT SCI & ENGN,DAVIS,CA 95616, USA. NR 37 TC 63 Z9 69 U1 0 U2 11 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAY 1 PY 1991 VL 26 IS 9 BP 2410 EP 2416 DI 10.1007/BF01130188 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA FL475 UT WOS:A1991FL47500020 ER PT J AU MAO, X KAMEDA, J AF MAO, X KAMEDA, J TI SMALL-PUNCH TECHNIQUE FOR MEASUREMENT OF MATERIAL DEGRADATION OF IRRADIATED FERRITIC ALLOYS SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID FRACTURE AB The yield stress and fracture strain of irradiated ferritic alloys were measured using a small-punch test. The characteristics of hardening and intergranular embrittlement induced during neutron irradiation (0.94 x 10(23) n m-2) at 395-degrees-C in ferritic alloys doped with Cu, P and/or C were investigated. The effect of neutron irradiation on hardening was found to be greater in alloys doped with Cu and/or P than in C-containing alloys. The neutron irradiation produced a more substantial increase in the ductile-brittle transition temperature in the Cu-doped alloy compared with the other alloys and cause a significant decrease in the ductility of the Cu-doped alloy. Intergranular and transgranular fracture occurred in the alloys doped without and with C, respectively. The neutron irradiation did not alter the fracture mode. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. RP MAO, X (reprint author), UNIV CALGARY,DEPT MECH ENGN,CALGARY T2N 1N4,ALBERTA,CANADA. NR 12 TC 20 Z9 22 U1 0 U2 2 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAY 1 PY 1991 VL 26 IS 9 BP 2436 EP 2440 DI 10.1007/BF01130192 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA FL475 UT WOS:A1991FL47500024 ER PT J AU KENKRE, VM SKALA, L WEISER, MW KATZ, JD AF KENKRE, VM SKALA, L WEISER, MW KATZ, JD TI THEORY OF MICROWAVE INTERACTIONS IN CERAMIC MATERIALS - THE PHENOMENON OF THERMAL RUNAWAY SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB A theory of the phenomenon of thermal runaway in ceramic materials undergoing microwave heating is presented on the basis of a simple temperature-time equation. The non-linear evolution inherent in the equation is shown to arise naturally from physical arguments and it is shown how the parameters of the theory may be calculated from the microscopic absorption processes and information about the material under consideration. The theory is applied to experimental observations reported on several different materials and shown to be in good agreement with the data. C1 UNIV NEW MEXICO,DEPT PHYS,ALBUQUERQUE,NM 87131. UNIV NEW MEXICO,DEPT MECH ENGN,ALBUQUERQUE,NM 87131. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RP KENKRE, VM (reprint author), UNIV NEW MEXICO,CTR MICROENGINEERED CERAM,ALBUQUERQUE,NM 87131, USA. NR 11 TC 45 Z9 48 U1 1 U2 8 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAY 1 PY 1991 VL 26 IS 9 BP 2483 EP 2489 DI 10.1007/BF01130199 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA FL475 UT WOS:A1991FL47500031 ER PT J AU MARQUESBONHAM, S AF MARQUESBONHAM, S TI THE DIRAC-EQUATION IN A NON-RIEMANNIAN MANIFOLD III - AN ANALYSIS USING THE ALGEBRA OF QUATERNIONS AND OCTONIONS SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Article AB The geometrical properties of a flat tangent space-time local to the manifold of the Einstein-Schrodinger nonsymmetric theory to which an internal octonionic space is attached, is developed here. As an application of the theroy, an octonionic Dirac equation for a spin-1/2 particle is also obtained, where is now used an octonionic-like gauge field. It is shown that the (quaternionic) nonsymmetric Yang-Mills theory can be easily recovered and from there, the usual gauge theory on a curved space. C1 NASA,FERMILAB ASTROPHYS CTR,FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. CTR BRASILEIRO PESQUISAS FIS,DEPT CAMPOS & PARTICULAS,BR-22290 RIO DE JANEIRO,RJ,BRAZIL. NR 18 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0022-2488 J9 J MATH PHYS JI J. Math. Phys. PD MAY PY 1991 VL 32 IS 5 BP 1383 EP 1394 DI 10.1063/1.529291 PG 12 WC Physics, Mathematical SC Physics GA FJ277 UT WOS:A1991FJ27700038 ER PT J AU WELLER, RE WIERMAN, EL MALAGA, CA BAER, JF LEMIEUX, TP AF WELLER, RE WIERMAN, EL MALAGA, CA BAER, JF LEMIEUX, TP TI BATTELLE PRIMATE FACILITY SO JOURNAL OF MEDICAL PRIMATOLOGY LA English DT Article DE NEOTROPICAL PRIMATES; REPRODUCTION ID AOTUS-NANCYMAI; OWL MONKEYS; CEBIDAE AB The Battelle Primate Facility houses one of the largest collections of neotropical primates in the United States. The facility is a research resource for undergraduate and graduate students, Battelle staff, as well as staff and faculty from U.S. and international institutions. Researchers have access to the animals for a variety of studies encompassing several disciplines, a large collection of preserved tissues, and an extensive biomedical database. The facility is a World Health Organization Collaborative Center for Clinical Pathology of Neotropical Primates and is involved with the Peruvian Primatological Project in Iquitos, Peru, which provides opportunities for research in primatology and conservation. RP WELLER, RE (reprint author), PACIFIC NW LAB, CTR LIFE SCI, DEV TOXICOL SECT, RICHLAND, WA 99352 USA. NR 9 TC 7 Z9 7 U1 1 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0047-2565 J9 J MED PRIMATOL JI J. Med. Primatol. PD MAY PY 1991 VL 20 IS 3 BP 133 EP 137 PG 5 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA GA920 UT WOS:A1991GA92000007 PM 1895333 ER PT J AU BISHOP, JE MATHIS, CA GERDES, JM WHITNEY, JM EATON, AM MAILMAN, RB AF BISHOP, JE MATHIS, CA GERDES, JM WHITNEY, JM EATON, AM MAILMAN, RB TI SYNTHESIS AND INVITRO EVALUATION OF 2,3-DIMETHOXY-5-(FLUOROALKYL)-SUBSTITUTED BENZAMIDES - HIGH-AFFINITY LIGANDS FOR CNS DOPAMINE-D2 RECEPTORS SO JOURNAL OF MEDICINAL CHEMISTRY LA English DT Article ID POTENTIAL ANTIPSYCHOTIC AGENTS; ANTIDOPAMINERGIC PROPERTIES; NEUROLEPTIC AGENTS; HUMAN-BRAIN; SEROTONIN RECEPTORS; BINDING-SITES; RAT-BRAIN; PET; RACLOPRIDE; ACID AB A number of 2,3-dimethoxy-5-(fluoroalkyl)-N-[(1-ethyl-2-pyrrolidinyl]benzamides (with or without a 6-hydroxy group) were synthesized and evaluated as dopamine D2 receptor ligands. The parent acids were synthesized via the Claisen rearrangement of the appropriate O-allyl ethers, which were derived from omicron-vanillic acid or 2,3-dimethoxysalicylic acid. A decrease in reactivity was found to be characteristic of pentasubstituted benzoates, and difficulties were encountered with the introduction of fluorine onto the ethyl side chains. The (fluoroethyl)- and (fluoropropyl)salicylamides were 5 times more potent than the corresponding benzamides in inhibiting [H-3]spiperone binding to the D2 receptor. These (fluoroalkyl)salicylamides are of potential value for in vivo positron emission tomography (PET) studies upon the basis of their relatively selective, high potency binding affinity for the D2 receptor. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV RES MED & RADIAT BIOPHYS,MS 55-121,1 CYCLOTRON RD,BERKELEY,CA 94720. UNIV N CAROLINA,SCH MED,BRAIN & DEV RES CTR,DEPT PSYCHIAT,CHAPEL HILL,NC 27599. UNIV N CAROLINA,SCH MED,DEPT PHARMACOL,CHAPEL HILL,NC 27599. OI Mailman, Richard/0000-0003-1353-2738 FU NIMH NIH HHS [MH-37404, MH-40537]; NINDS NIH HHS [NS-22899] NR 67 TC 41 Z9 45 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-2623 J9 J MED CHEM JI J. Med. Chem. PD MAY PY 1991 VL 34 IS 5 BP 1612 EP 1624 DI 10.1021/jm00109a013 PG 13 WC Chemistry, Medicinal SC Pharmacology & Pharmacy GA FL859 UT WOS:A1991FL85900013 PM 1827843 ER PT J AU MULFORD, RN AF MULFORD, RN TI THE FOURIER-TRANSFORM SPECTRUM OF THE INFRARED COMBINATION BAND (NU-1+NU-3) OF UF6 SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article RP MULFORD, RN (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 5 TC 1 Z9 1 U1 1 U2 2 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD MAY PY 1991 VL 147 IS 1 BP 260 EP 266 DI 10.1016/0022-2852(91)90184-C PG 7 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA FH196 UT WOS:A1991FH19600022 ER PT J AU ROSENBERG, J KEUNINGS, R AF ROSENBERG, J KEUNINGS, R TI NUMERICAL-INTEGRATION OF DIFFERENTIAL VISCOELASTIC MODELS SO JOURNAL OF NON-NEWTONIAN FLUID MECHANICS LA English DT Article DE FINITE ELEMENT TECHNIQUES; NUMERICAL SIMULATION; STREAMLINE INTEGRATION; STREAMLINE UPWINDING; VISCOELASTIC FLOW ID FINITE-ELEMENT; FLOW AB Various numerical techniques are compared in the integration of the upper-convected Maxwell constitutive model on the basis of given kinematics in the planar stick-slip problem. The techniques include three different finite element methods (Galerkin, streamline-upwind, and streamline-upwind Petrov-Galerkin), and a streamline integration scheme. The results illustrate the failure of Galerkin's method in flows possessing steep solution gradients or singularities. The two upwinding techniques are shown to be superior to Galerkin's method but they remain inaccurate near singularities and in flow regions where the solution gradients are transverse to the streamlines. The streamline integration scheme, which in essence is a method of characteristics applied to the purely hyperbolic constitutive model, leads to stable and accurate stress predictions even close to singularities. In view of these results, we have developed a Picard iterative method based on streamline integration to produce solutions to the full set of governing equations for an Oldroyd-B fluid. Results for the stick-slip flow problem could only be obtained for modestly low values of the Weissenberg number with a rather coarse discretization of the flow domain. The reason for the poor convergence properties of the iterative scheme is the large sensitivity of the computed extra-stress to minute changes in kinematics in flow regions of high stress gradients. Our stress integrator based on streamline integration increases the (iterative) convergence difficulties since it captures those stress gradients with great accuracy. The successful use of streamline integration in viscoelastic calculations requires further work towards decoupled iterative schemes capable of handling large stress sensitivity. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. CATHOLIC UNIV LOUVAIN,UNITE MECAN APPL,B-1348 LOUVAIN,BELGIUM. NR 11 TC 22 Z9 22 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0257 J9 J NON-NEWTON FLUID JI J. Non-Newton. Fluid Mech. PD MAY PY 1991 VL 39 IS 3 BP 269 EP 290 DI 10.1016/0377-0257(91)80018-F PG 22 WC Mechanics SC Mechanics GA FQ600 UT WOS:A1991FQ60000003 ER PT J AU MOALEM, M OLANDER, DR AF MOALEM, M OLANDER, DR TI OXIDATION OF ZIRCALOY BY STEAM SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID HIGH-TEMPERATURE OXIDATION; DIFFUSION AB The oxidation of Zircaloy by steam and by steam-hydrogen mixtures was studied experimentally from 1100-1600-degrees-C using the continuously-recording gravimetric method. Parabolic kinetics based on oxygen diffusion in the solid were followed at low temperatures but steam starvation, nonisothermal behavior, and finite medium effects dominated at temperatures above about 1500-degrees-C. The effect of high dilution of the steam by hydrogen was to accelerate oxidation initially because of the heat released by hydrogen absorption in the metal. At high temperatures, oxygen uptake kinetics were nonparabolic and required analysis by a fundamental diffusion model in which the initial effects are incorporated. C1 UNIV CALIF BERKELEY,DEPT NUCL ENGN,BERKELEY,CA 94720. RP MOALEM, M (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT & CHEM SCI,BERKELEY,CA 94720, USA. NR 28 TC 36 Z9 37 U1 3 U2 13 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 MAY-JUN PY 1991 VL 182 BP 170 EP 194 DI 10.1016/0022-3115(91)90428-A PG 25 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA FT837 UT WOS:A1991FT83700020 ER PT J AU KLUEH, RL VITEK, JM AF KLUEH, RL VITEK, JM TI TENSILE PROPERTIES OF 9CR-1MOVNB AND 12CR-1MOVW STEELS IRRADIATED TO 23-DPA AT 390 TO 550-DEGREES-C SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article AB Normalized-and-tempered 9Cr-1MoVNb and 12Cr-1MoVW steels were irradiated in the Experimental Breeder Reactor II (EBR-II) at 390, 450, 500, and 550-degrees-C to displacement damage levels of up to 23 to 25 dpa. Tensile tests were conducted at the irradiation temperatures on three types of specimens: irradiated specimens, normalized-and-tempered specimens, and specimens thermally aged 5000 h at the irradiation temperatures. Observations from these tests were compared with results on these same materials irradiated in EBR-II at the same temperatures to 9 to 13 dpa. Irradiation of specimens at 390-degrees-C to 23 to 25 dpa caused an increase in strength and a decrease in ductility relative to the aged and unaged control specimens; however, there was little change from the specimens irradiated to 9 to 13 dpa. After irradiation at 450, 500, and 550-degrees-C, there was little difference between the irradiated specimens, the normalized-and-tempered specimens, and the specimens aged for 5000 h. Results were interpreted in terms of the precipitate and dislocation microstructures developed during normalizing and tempering, thermal aging, and irradiation. RP KLUEH, RL (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,POB 2008,OAK RIDGE,TN 37831, USA. NR 12 TC 35 Z9 36 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 MAY-JUN PY 1991 VL 182 BP 230 EP 239 DI 10.1016/0022-3115(91)90433-8 PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA FT837 UT WOS:A1991FT83700025 ER PT J AU MARTZ, JC HESS, DW HASCHKE, JM WARD, JW FLAMM, BF AF MARTZ, JC HESS, DW HASCHKE, JM WARD, JW FLAMM, BF TI DEMONSTRATION OF PLUTONIUM ETCHING IN A CF4/O2 RF GLOW-DISCHARGE SO JOURNAL OF NUCLEAR MATERIALS LA English DT Letter ID EMISSION-SPECTROSCOPY; PLASMAS; DENSITY C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV NUCL MAT TECHNOL,LOS ALAMOS,NM 87545. RP MARTZ, JC (reprint author), UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720, USA. NR 17 TC 18 Z9 18 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 MAY-JUN PY 1991 VL 182 BP 277 EP 280 DI 10.1016/0022-3115(91)90442-A PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA FT837 UT WOS:A1991FT83700034 ER PT J AU WRIGHT, RN VANSICLEN, CD USMAR, SG MOCHEL, ME AF WRIGHT, RN VANSICLEN, CD USMAR, SG MOCHEL, ME TI ACCELERATED HELIUM BUBBLE-GROWTH IN ALUMINUM IN THE PRESENCE OF LEAD PRECIPITATES SO JOURNAL OF NUCLEAR MATERIALS LA English DT Letter ID POSITRON-ANNIHILATION; PARAMETERS C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV ILLINOIS,CTR MICROANAL MAT,URBANA,IL 61801. RP WRIGHT, RN (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415, USA. NR 12 TC 12 Z9 12 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 MAY-JUN PY 1991 VL 182 BP 281 EP 286 DI 10.1016/0022-3115(91)90443-B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA FT837 UT WOS:A1991FT83700035 ER PT J AU STABIN, MG WATSON, EE MARCUS, CS SALK, RD AF STABIN, MG WATSON, EE MARCUS, CS SALK, RD TI RADIATION-DOSIMETRY FOR THE ADULT FEMALE AND FETUS FROM I-131 ADMINISTRATION IN HYPERTHYROIDISM SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article AB Through a study of the iodine kinetics of 127 patients, we have developed radiation dose estimates to major organs and the fetus for patients with varying degrees of hyperthyroidism. We observed a negative correlation between maximum thyroid uptake and biologic half-time of iodine in the thyroid and used this correlation to predict the biologic half-time at fixed values of maximum thyroid uptake. Dose estimates to the bladder, gonads, marrow, thyroid, uterus, and whole body were estimated for maximum thyroid uptakes from 20% to 100%. Bladder dose varied from 0.6 to 1.0 mGy/MBq and dose to the uterus varied from 0.036 to 0.063 mGy/MBq under different model assumptions. Dose estimates to the fetus and fetal thyroid were approximated at all stages of pregnancy. Average fetal dose was a maximum between 0 and 2 mo of pregnancy, with the maximum ranging from 0.048 mGy/MBq to 0.083 mGy/MBq, depending on model assumptions. Some radiation risks for irradiation of the fetus and the fetal thyroid are discussed. C1 UNIV CALIF LOS ANGELES,LOS ANGELES CTY HARBOR MED CTR,NUCL MED OUTPATIENT CLIN,TORRANCE,CA 90509. RP STABIN, MG (reprint author), OAK RIDGE ASSOCIATED UNIV,DIV MED SCI,OAK RIDGE,TN 37830, USA. NR 25 TC 28 Z9 28 U1 0 U2 2 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 22090-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1991 VL 32 IS 5 BP 808 EP 813 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA FL183 UT WOS:A1991FL18300017 PM 2022987 ER PT J AU WIGGS, LD COXDEVORE, CA WILKINSON, GS REYES, M AF WIGGS, LD COXDEVORE, CA WILKINSON, GS REYES, M TI MORTALITY AMONG WORKERS EXPOSED TO EXTERNAL IONIZING-RADIATION AT A NUCLEAR FACILITY IN OHIO SO JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL MEDICINE LA English DT Article ID EMPLOYEES; SURVIVAL; PLANT; FUELS AB In a cohort mortality study of white men employed by the Mound Facility (1947 through 1979), observed deaths did not exceed those expected based on US death rates for the overall cohort or for the subcohort monitored for external ionizing radiation. Among the radiation-monitored subcohort, mortality for workers with cumulative radiation doses of at least 10 mSv was not significantly increased when compared with mortality for coworkers with cumulative doses of less than 10 mSv. A significant dose-response based on a Mantel-Haenszel test of trend was observed for all leukemias. However, when a death from chronic lymphatic leukemia, a type of leukemia generally not regarded as radiogenic, was removed from the analyses, the strength of the dose-response was reduced. RP WIGGS, LD (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,OCCUPAT MED GRP,POB 1663,LOS ALAMOS,NM 87545, USA. NR 19 TC 22 Z9 22 U1 0 U2 0 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 1076-2752 J9 J OCCUP ENVIRON MED JI J. Occup. Environ. Med. PD MAY PY 1991 VL 33 IS 5 BP 632 EP 637 PG 6 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA FL740 UT WOS:A1991FL74000011 PM 1870016 ER PT J AU TONG, C SWARZTRAUBER, PN AF TONG, C SWARZTRAUBER, PN TI ORDERED FAST FOURIER-TRANSFORMS ON A MASSIVELY PARALLEL HYPERCUBE MULTIPROCESSOR SO JOURNAL OF PARALLEL AND DISTRIBUTED COMPUTING LA English DT Article ID COMMUNICATION; ARCHITECTURES; ALGORITHMS; COMPUTERS C1 NASA,AMES RES CTR,ADV COMP SCI RES INST,MOFFETT FIELD,CA 94035. UNIV CALIF LOS ANGELES,DEPT MATH,LOS ANGELES,CA 90024. NATL CTR ATMOSPHER RES,BOULDER,CO 80307. UNIV COLORADO,DEPT COMP SCI,BOULDER,CO 80309. RP TONG, C (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. NR 20 TC 12 Z9 15 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0743-7315 J9 J PARALLEL DISTR COM JI J. Parallel Distrib. Comput. PD MAY PY 1991 VL 12 IS 1 BP 50 EP 59 DI 10.1016/0743-7315(91)90028-8 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA FL188 UT WOS:A1991FL18800005 ER PT J AU GRABIAK, M GYULASSY, M AF GRABIAK, M GYULASSY, M TI DYNAMIC PROPERTIES AND FLUX TUBES OF THE FRIEDBERG-LEE MODEL SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article ID SOLITON-BAG MODEL; NON-TOPOLOGICAL SOLITONS; QUANTUM CHROMODYNAMICS; CONFINEMENT; HADRONS; COLLISIONS AB A new non-polynomial parametrization for the dielectric function of the Friedberg-Lee model is suggested to enforce the confinement of dynamical gluons. We investigated flux tube solutions of this model and show how divergences of the colour magnetic quark interaction can be avoided. As effective models for confinement, we contrast the Friedberg-Lee model and Abelian Higgs models. We point out pathological properties of the Friedberg-Lee model: (i) the lack of confinement of high-frequency gluons and (ii) sensitivity of the scalar field dynamics to unphysical vector fields in the non-perturbative vacuum, sigma = sigma(V). These problems can be cured only by requiring that all derivatives of the dielectric function kappa-(sigma) vanish in the non-perturbative vacuum. Using an ansatz with this property we investigate flux tube solutions. As effective models for confinement, we contrast the Friedberg-Lee model and the Abelian Higgs model. RP GRABIAK, M (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720, USA. NR 35 TC 8 Z9 8 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAY PY 1991 VL 17 IS 5 BP 583 EP 603 DI 10.1088/0954-3899/17/5/008 PG 21 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA FK580 UT WOS:A1991FK58000008 ER PT J AU WEIGEL, MK HADDAD, S WEBER, F AF WEIGEL, MK HADDAD, S WEBER, F TI SEMICLASSICAL EXPANSIONS OF THE NUCLEAR RELATIVISTIC HARTREE-FOCK THEORY SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article ID SEMI-CLASSICAL APPROXIMATIONS; POTENTIALS; HAMILTONIANS; SYSTEMS; MATTER AB Semiclassical expansions for Green functions, self-energy, phase-space density and density are given and discussed. The many-body problem was treated in the relativistic Hartree-Fock approximation with a Lagrangian with a standard OBE potential structure including the possibility of space-dependent couplings. The expansions are obtained by formulating the many-body problem in the mixed position-momentum (Wigner) representation and application of the h-Wigner-Kirkwood expansion scheme. The resulting self-consistency problems for the zeroth and second order are formulated in three versions. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB, DIV NUCL SCI, BERKELEY, CA 94720 USA. RP WEIGEL, MK (reprint author), LUDWIG MAXIMILIANS UNIV, SEKT PHYS, AM COULOMBWALL 1, W-8046 GARCHING, GERMANY. NR 35 TC 23 Z9 23 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAY PY 1991 VL 17 IS 5 BP 619 EP 644 DI 10.1088/0954-3899/17/5/010 PG 26 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA FK580 UT WOS:A1991FK58000010 ER PT J AU SWINDEMAN, RW GOLD, M AF SWINDEMAN, RW GOLD, M TI DEVELOPMENTS IN FERROUS ALLOY TECHNOLOGY FOR HIGH-TEMPERATURE SERVICE SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID STAINLESS-STEEL AB Developments during the past twenty-five years are outlined for the technology of ferrous alloys needed in elevated temperature service. These developments include new alloys with improved strength and corrosion resistance for use in nuclear, fossil, and petrochemical applications. Specific groups of alloys that are addressed include vanadium-modified low alloy steels, 9Cr-1Mo-V steel, niobium-modified lean stainless steels, and high chrome-nickel iron alloys. A brief description of coating and claddings for improved corrosion resistance is also provided. C1 OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831. BABCOCK & WILCOX CO,BARBERTON,OH 44203. NR 39 TC 1 Z9 2 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD MAY PY 1991 VL 113 IS 2 BP 133 EP 140 DI 10.1115/1.2928737 PG 8 WC Engineering, Mechanical SC Engineering GA HP754 UT WOS:A1991HP75400004 ER PT J AU CHEN, SS AF CHEN, SS TI FLOW-INDUCED VIBRATIONS IN 2-PHASE FLOW SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID CROSS-FLOW; FORCES; TUBES; MASS AB Two-phase flow exists in many shell-and-tube heat exhangers and power generation components. The flowing fluid is a source of energy that can induce small-amplitude subcritical oscillations and large-amplitude dynamic instabilities. In fact, many practical system components have experienced excessive flow-induced vibrations. This paper reviews the current understanding of vibration of circular cylinders in quiescent fluid, cross-flow, and axial flow, with emphasis on excitation mechanisms, mathematical models, and available experimental data. A unified theory is presented for cylinders oscillating under different flow conditions. C1 ARGONNE NATL LAB,DIV NAT & COMPONENTS TECHNOL,ARGONNE,IL 60439. NR 58 TC 18 Z9 18 U1 0 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD MAY PY 1991 VL 113 IS 2 BP 234 EP 241 DI 10.1115/1.2928751 PG 8 WC Engineering, Mechanical SC Engineering GA HP754 UT WOS:A1991HP75400018 ER PT J AU AUYANG, MK BLEVINS, RD MULCAHY, TM AF AUYANG, MK BLEVINS, RD MULCAHY, TM TI FLOW-INDUCED VIBRATION ANALYSIS OF TUBE BUNDLES - A PROPOSED SECTION III APPENDIX N NONMANDATORY CODE SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID CROSS-FLOW; ARRAYS; COMPONENTS; GUIDELINES; CYLINDERS AB This paper presents guidelines for flow-induced vibration analysis of tubes and tube bundles such as those commonly encountered in steam generators, heat exchangers, condensers and nuclear fuel bundles. It was proposed as a nonmandatory code to be included in Section III Appendix N (N-1300 series) of the American Society of Mechanical Engineers (ASME) Boiler Code. In preparing this code, the authors tried to limit themselves to the better-defined flow excitation mechanisms-vortex-induced vibration, fluid-elastic instability and turbulence-induced vibration-and include only the more-established methods. References are, however, given for other methods whenever justified. This guideline covers only design analysis. A companion guideline on the testing and data analysis of heat exchanger tube banks was proposed as part of the ASME Code on Operations and Maintenance of Nuclear Plants. The latter is not included in this paper. C1 B & W NUCL TECHNOL,LYNCHBURG,VA 24506. ROHR IND,CHULA VISTA,CA 92012. ARGONNE NATL LAB,ARGONNE,IL 60439. NR 64 TC 9 Z9 9 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD MAY PY 1991 VL 113 IS 2 BP 257 EP 267 DI 10.1115/1.2928753 PG 11 WC Engineering, Mechanical SC Engineering GA HP754 UT WOS:A1991HP75400020 ER PT J AU LIU, WK CHEN, YJ TSUKIMORI, K URAS, RA AF LIU, WK CHEN, YJ TSUKIMORI, K URAS, RA TI RECENT ADVANCES IN DYNAMIC BUCKLING ANALYSIS OF LIQUID-FILLED SHELLS SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID EXCITATION AB The dynamic buckling of liquid-filled shells is reviewed. Comparison of the analysis with experimental results is presented. The governing equations of dynamic buckling of liquid-filled imperfect shells are then derived. A simple imperfection pattern is chosen to explain the additional buckling modes encountered in the experiments. C1 NORTHWESTERN UNIV,DEPT MECH ENGN,EVANSTON,IL 60208. ARGONNE NATL LAB,DIV REACTOR ENGN,ARGONNE,IL 60439. RI Liu, Wing/B-7599-2009 NR 9 TC 5 Z9 5 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD MAY PY 1991 VL 113 IS 2 BP 314 EP 320 DI 10.1115/1.2928760 PG 7 WC Engineering, Mechanical SC Engineering GA HP754 UT WOS:A1991HP75400027 ER PT J AU HILLSMAN, EL AF HILLSMAN, EL TI SPATIAL ENERGY ANALYSIS - LUNDQUIST,L, MATTSSON,LG, ERIKSSON,EA SO JOURNAL OF REGIONAL SCIENCE LA English DT Book Review RP HILLSMAN, EL (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BLACKWELL PUBLISHERS PI CAMBRIDGE PA 238 MAIN STREET, CAMBRIDGE, MA 02142 SN 0022-4146 J9 J REGIONAL SCI JI J. Reg. Sci. PD MAY PY 1991 VL 31 IS 2 BP 233 EP 235 PG 3 WC Economics; Environmental Studies; Planning & Development SC Business & Economics; Environmental Sciences & Ecology; Public Administration GA FM075 UT WOS:A1991FM07500016 ER PT J AU TUSKAN, GA LAUGHLIN, K AF TUSKAN, GA LAUGHLIN, K TI WINDBREAK SPECIES PERFORMANCE AND MANAGEMENT-PRACTICES AS REPORTED BY MONTANA AND NORTH-DAKOTA LANDOWNERS SO JOURNAL OF SOIL AND WATER CONSERVATION LA English DT Article ID PLAINS AB A survey of 896 randomly selected landowners/operators in eight central and eastern Montana countries and six North Dakota countries was undertaken to generate a data base with which to evaluate the relationship between windbreak species performance and management practices and/or environmental conditions. Survey respondents indicated the use of 61 tree and shrub species in their farmstead and field windbreaks. Generally, species varied in performance rankings, with deciduous shrubs receiving the highest rankings and coniferous trees receiving the lowest. Based on chi-square analyses and Spearman's correlation coefficient, speices performance rankings also varied in association with the management practices used by the landowner/operator, site topography, and soil alkalinity. Recommendations are made for expanded use of currently available tree and shrub species to meet the demand for new windbreak plant materials and the implementation of species-specific management practices. C1 MONTANA STATE UNIV,COOPERAT EXTENS SERV,BOZEMAN,MT 59717. N DAKOTA STATE UNIV,DEPT HORT & FORESTRY,FARGO,ND 58105. RP TUSKAN, GA (reprint author), OAK RIDGE NATL LAB,POB 2008,OAK RIDGE,TN 37831, USA. RI Tuskan, Gerald/A-6225-2011 OI Tuskan, Gerald/0000-0003-0106-1289 NR 18 TC 1 Z9 2 U1 1 U2 2 PU SOIL WATER CONSERVATION SOC PI ANKENY PA 7515 N E ANKENY RD, ANKENY, IA 50021-9764 SN 0022-4561 J9 J SOIL WATER CONSERV JI J. Soil Water Conserv. PD MAY-JUN PY 1991 VL 46 IS 3 BP 225 EP 228 PG 4 WC Ecology; Soil Science; Water Resources SC Environmental Sciences & Ecology; Agriculture; Water Resources GA FT165 UT WOS:A1991FT16500015 ER PT J AU ZANGRANDO, F FERNANDO, HJS AF ZANGRANDO, F FERNANDO, HJS TI A PREDICTIVE MODEL FOR THE MIGRATION OF DOUBLE-DIFFUSIVE INTERFACES SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID CONVECTION AB A model is proposed to predict the rate of entrainment and detrainment and the conditions for equilibrium for diffusive boundaries of a double-diffusive fluid layer. The system consists of a stably stratified layer overlying a mixed, turbulently convecting layer, which is representative of solar pond situations. The results show that the entrainment/detrainment laws are strongly dependent on the operating parameter range. At equilibrium, the density stability ratio at the edge of the convection zone depends only on the ratio of molecular diffusivities. The predictions are in satisfactory agreement with the available experimental data at large values of salinity and temperature gradients. C1 SOLAR ENERGY RES INST,THERMAL RES BRANCH,GOLDEN,CO 80401. ARIZONA STATE UNIV,DEPT MECH & AEROSP ENGN,TEMPE,AZ 85287. ARIZONA STATE UNIV,DEPT MECH & AEROSP ENGN,TEMPE,AZ 85287. NR 25 TC 8 Z9 8 U1 0 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD MAY PY 1991 VL 113 IS 2 BP 59 EP 65 DI 10.1115/1.2929959 PG 7 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA HP745 UT WOS:A1991HP74500001 ER PT J AU LEONARD, SR SNYDER, BS BREWER, L STACY, AM AF LEONARD, SR SNYDER, BS BREWER, L STACY, AM TI STRUCTURE DETERMINATIONS OF 2 NEW TERNARY OXIDES - TI3PDO AND TI4PD2O SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID REDUCTION TEMPERATURE; NEUTRON-DIFFRACTION; COMPOSITES C1 UNIV CALIF BERKELEY, DEPT CHEM, BERKELEY, CA 94720 USA. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB, DIV MAT & CHEM SCI, BERKELEY, CA 94720 USA. NR 29 TC 7 Z9 7 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 EI 1095-726X J9 J SOLID STATE CHEM JI J. Solid State Chem. PD MAY PY 1991 VL 92 IS 1 BP 39 EP 50 DI 10.1016/0022-4596(91)90240-I PG 12 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA FJ626 UT WOS:A1991FJ62600005 ER PT J AU KNAPP, R PAPANICOLAOU, G WHITE, B AF KNAPP, R PAPANICOLAOU, G WHITE, B TI TRANSMISSION OF WAVES BY A NONLINEAR RANDOM MEDIUM SO JOURNAL OF STATISTICAL PHYSICS LA English DT Article DE LOCALIZATION; NONLINEAR WAVES ID RADIATIVE TRANSPORT-THEORY; POWER STATISTICS; ONE-DIMENSION; PROPAGATION AB We study analytically and numerically the effect of nonlinearity on transmission of waves through a random medium. We introduce and analyze quantities associated with the scattering problem that clarify the lack of uniqueness due to the nonlinearity as well as the localization of waves due to the random inhomogeneities. We show that nonlinearity tends to delocalize the waves and that for very large scattering regions the average transmitted energy is small. C1 COURANT INST,NEW YORK,NY 10012. EXXON RES & ENGN CO,ANNANDALE,NJ 08801. RP KNAPP, R (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 11 TC 18 Z9 18 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0022-4715 J9 J STAT PHYS JI J. Stat. Phys. PD MAY PY 1991 VL 63 IS 3-4 BP 567 EP 583 DI 10.1007/BF01029200 PG 17 WC Physics, Mathematical SC Physics GA FP349 UT WOS:A1991FP34900007 ER PT J AU LYON, RE AF LYON, RE TI SHEAR-STRENGTH OF A DUCTILE MATERIAL FROM TORSION OF SOLID CYLINDERS SO JOURNAL OF TESTING AND EVALUATION LA English DT Article DE SHEAR STRENGTH; TORSION; DUCTILE; YIELDING; THIN-WALLED TUBE; PLASTICITY; EPOXY AB The shear strengths of two ductile epoxies are obtained from solid cylinder torsion using a data reduction scheme. The results are in quantitative agreement with shear data from torsion of thin-walled tubes of the same materials, particularly with regard to the coincidence of the peak yield stress and strain. The described technique is useful for characterizing ductile material behavior in shear using a simple, solid cylinder specimen. RP LYON, RE (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,LIVERMORE,CA 94550, USA. NR 2 TC 3 Z9 3 U1 0 U2 1 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 SN 0090-3973 J9 J TEST EVAL JI J. Test. Eval. PD MAY PY 1991 VL 19 IS 3 BP 240 EP 243 PG 4 WC Materials Science, Characterization & Testing SC Materials Science GA FL777 UT WOS:A1991FL77700008 ER PT J AU TURK, BH PRILL, RJ FISK, WJ GRIMSRUD, DT SEXTRO, RG AF TURK, BH PRILL, RJ FISK, WJ GRIMSRUD, DT SEXTRO, RG TI EFFECTIVENESS OF RADON CONTROL TECHNIQUES IN 15 HOMES SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Review ID HOUSES AB Randon control systems were installed and evaluated in fourteen homes in the Spokane River Valley/Rathdrum Prairie and in one home in Vancouver, Washington. Because of local soil conditions, subsurface ventilation (SSV) by pressurization was always more effective in these houses than SSV by depressurization in reducing indoor radon levels to below guidelines. Basement overpressurization was successfully applied in five houses with airtight basements where practical-sized fans could develop an overpressure of 1 to 3 Pascals. Crawlspace ventilation was more effective than crawlspace isolation in reducing radon entry from the crawlspace, but had to be used in conjunction with other mitigation techniques, since the houses also had basements. Indoor radon concentrations in two houses with air-to-air heat exchangers (AAHX) were reduced to levels inversely dependent on the new total ventilation rates and were lowered even further in one house where the air distribution system was modified. Sealing penetrations in the below-grade surfaces of substructures was relatively ineffective in controlling radon. Operation of the radon control systems (except for the AAHX's) made no measureable change in ventilation rates or indoor concentrations of other measured pollutants. Installation costs by treated floor area ranged from approximately $4/m2 for sealing to $28/m2 for the AAHX's. Based on the low electric rates for the region, annual operating costs for the active systems were estimated to be approximately $60 to $170. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV APPL SCI,INDOOR ENVIRONM PROGRAM,BERKELEY,CA 94720. NR 27 TC 7 Z9 7 U1 1 U2 2 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA PO BOX 2861, PITTSBURGH, PA 15230 SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD MAY PY 1991 VL 41 IS 5 BP 723 EP 734 PG 12 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA FM560 UT WOS:A1991FM56000008 PM 1863451 ER PT J AU SUGAMA, T CARCIELLO, NR AF SUGAMA, T CARCIELLO, NR TI STRENGTH DEVELOPMENT IN PHOSPHATE-BONDED CALCIUM ALUMINATE CEMENTS SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article DE CEMENTS; PHOSPHATES; CALCIUM; ALUMINATES; HYDROXYAPATITE ID PHOTOELECTRON-SPECTROSCOPY; GLASSES; SPECTRA AB The chemical reaction at room temperature between calcium aluminate cement (CAC) and NH4H2PO4-based fertilizer solution causes the formation of ammonium calcium pyrophosphate (AmCPP) as an amorphous cementitious phase. This phase was responsible for the development of strength in rapid-setting phosphate-bonded cement (PBC) specimens. Hydrothermal treatment of PBC at 200-degrees-C led to phase transformations of AmCPP and CAC into crystalline hydroxyapatite as the major phase and anorthite as the minor one. The moderate growth of these interlocked crystals in the interspaces of amorphous phases played an important role in creating a dense microstructure, thereby conferring a very high strength to the PBC. In contrast, an excessive crystal growth, which caused the formation of porous microstructure, resulted in a reduction in strength. RP SUGAMA, T (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,DIV ENERGY EFFICIENCY & CONSERVAT,UPTON,NY 11973, USA. NR 16 TC 16 Z9 16 U1 1 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 1991 VL 74 IS 5 BP 1023 EP 1030 DI 10.1111/j.1151-2916.1991.tb04338.x PG 8 WC Materials Science, Ceramics SC Materials Science GA FL762 UT WOS:A1991FL76200019 ER PT J AU SHORT, RT GRIMM, CC TODD, PJ AF SHORT, RT GRIMM, CC TODD, PJ TI MONITOR FOR DISPLAYING REAL-TIME IMAGES OF LOW-ENERGY ION-BEAMS SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article AB A monitor that provides real-time images of low energy (< 50 eV) ion beams has been designed, constructed, and tested. The cross-sectional image of the beam at the entrance aperture of the monitor is magnified by a factor of 6.5 and displayed on a CRT, following current amplification by using a dual microchannel plate assembly. The monitor provides unambiguous information regarding the cross section of any low energy ion beam. Application in the design and testing of quadrupole-based mass spectrometers is emphasized. C1 OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37830. NR 10 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD MAY-JUN PY 1991 VL 2 IS 3 BP 226 EP 231 DI 10.1016/1044-0305(91)80048-C PG 6 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA FL429 UT WOS:A1991FL42900006 PM 24242277 ER PT J AU VALLET, CE AF VALLET, CE TI COMPUTER-SIMULATIONS OF THE SEMICONDUCTOR-METAL TRANSITION IN RU/TI AND IR/TI MIXED OXIDES SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID IMPLANTED TITANIUM ELECTRODES; ION-IMPLANTATION; CHLORINE EVOLUTION; ANODIC FILMS; ELECTROCATALYSIS; SOLITONS; SPECTROSCOPY; DIOXIDE AB The mixed oxide films, M(x)Ti(1-x)O2 (M = Ru, Ir), formed by anodic oxidation of M-implanted titanium alloys exhibit a transition from semiconducting to metallic behavior for a M/Ti ratio on the order of 0.1. Two-dimensional computer simulations are used to describe the process by a percolation model. Analysis of results of the calculations in terms of the composition dependence of the number of "metallic" clusters and of the size of the largest one suggests a mechanism involving the creation and the spreading of impurity bands in the forbidden bandgap. Metallic behavior would be obtained by the overlap of impurity bands with the conduction band. RP VALLET, CE (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 27 TC 9 Z9 9 U1 0 U2 0 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1991 VL 138 IS 5 BP 1234 EP 1238 DI 10.1149/1.2085765 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA FL286 UT WOS:A1991FL28600010 ER PT J AU JORDAN, KG TOBIAS, CW AF JORDAN, KG TOBIAS, CW TI THE EFFECT OF INHIBITOR TRANSPORT ON LEVELING IN ELECTRODEPOSITION SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID BOUNDARY ELEMENT; SIMULATION; MODEL AB The electrodeposition of nickel into an angular trench in the presence of coumarin, a widely used inhibitor, is simulated using boundary layer approximations representative of flow parallel and transverse to the groove. Based on the diffusion-adsorption mechanism of leveling action, the dependence of the developing contours on variations in the Langmuir coefficient and inhibitor/metal-ion flux ratio are investigated. Leveling efficiency is shown to be highest for thin, planar boundary layers, and lowest for contour following boundary layers. The model successfully predicts the leveling-off of the inhibitor effect with increasing inhibitor vs. metal-ion flux, and that there is an optimal mass transfer boundary layer thickness, or flux of additive which results in superior leveling performance. Satisfactory agreement is found between the predicted contours, obtained by solving the model equations using the boundary element method, and the experimental leveling efficiencies determined by previous investigators. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT & CHEM SCI,BERKELEY,CA 94720. NR 34 TC 44 Z9 44 U1 0 U2 7 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1991 VL 138 IS 5 BP 1251 EP 1259 DI 10.1149/1.2085768 PG 9 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA FL286 UT WOS:A1991FL28600013 ER PT J AU MORRIS, DE SMITH, WH AF MORRIS, DE SMITH, WH TI DIRECT VOLTAMMETRIC DETERMINATION OF THE EQUILIBRIUM ISOTOPE EFFECT IN NAPHTHALENE-H8/D8, ANTHRACENE-H10/D10, AND BENZOPHENONE-(CO)-C-12/(CO)-C-13 SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID SOLUTION ELECTRON-AFFINITIES; PHASE; REDUCTION AB Measurable differences in the reduction potentials (DELTA-E) of naphthalene-h8 vs. naphthalene-d8 (-13 +/- 2 mV) and anthracene-h10 vs. anthracene-d10 (-12 +/- 2 mV) have been determined by cyclic voltammetry in 0.1M tetra n-butyl ammonium fluorborate (TBABF4)-tetrahydrofuran (THF). These results corroborate earlier reports of the existence of a large equilibrium isotope effect for these deuterated polyacene molecules. These DELTA-E values correspond to isotope separation factors (alpha) at room temperature of 1.7 for the naphthalene isomers and 1.6 for the anthracene isomers. A much smaller potential difference is found for benzophenone-(CO)-C-12 vs. benzophenone-(CO)-C-13 (-2 +/- 2 mV) in 0.1M TBABF4 dimethoxyethane (DME). This result is inconsistent with previous reports of a large isotope effect for this and related isotopically substituted carbonyl-containing moieties. Consideration of ion-pairing effects in these low dielectric solvents vis a vis existing theories of equilibrium isotope effects suggests that the conditions employed in the present study should have been the most favorable for enhancement of an isotope effect in solution. C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV NUCL MAT TECHNOL,LOS ALAMOS,NM 87545. RP MORRIS, DE (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV ISOTOPE & NUCL CHEM,LOS ALAMOS,NM 87545, USA. RI Morris, David/A-8577-2012 NR 13 TC 10 Z9 10 U1 0 U2 1 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1991 VL 138 IS 5 BP 1351 EP 1353 DI 10.1149/1.2085784 PG 3 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA FL286 UT WOS:A1991FL28600029 ER PT J AU GUI, J DEVINE, TM AF GUI, J DEVINE, TM TI OBTAINING SURFACE-ENHANCED RAMAN-SPECTRA FROM THE PASSIVE FILM ON IRON SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID SILVER ELECTRODE; SCATTERING; SERS; SPECTROSCOPY; DEPOSITION; ADSORBATES; INTERFACE; PYRIDINE AB Surface-enhanced Raman spectra (SERS) have been obtained from an ion electrode that contains on its surface a discontinuous layer of silver. The mechanism of Raman enhancement of this system has been explored through a systematic study of the time stability and the potential reversibility of SERS spectra as well as the relation between the amount of silver deposited and the intensity of SERS. It is concluded that the local electromagnetic field mechanism is the dominant contributor to enhancement in this system. It is also shown that the anodic polarization characteristics of the iron electrode are unaffected by the presence of the discontinuous silver layer. Comparisons between in situ and ex situ, as well as in situ and semi-in situ Raman spectra have indicated the importance of characterizing the anodic passive film by in situ techniques. The limitation and possible extensions of the SERS technique in studies of passivity are also discussed. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720. RP GUI, J (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV MAT & CHEM SCI,LOS ALAMOS,NM 87545, USA. NR 32 TC 58 Z9 64 U1 0 U2 3 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1991 VL 138 IS 5 BP 1376 EP 1384 DI 10.1149/1.2085790 PG 9 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA FL286 UT WOS:A1991FL28600035 ER PT J AU WOODS, BW PAYNE, SA MARION, JE HUGHES, RS DAVIS, LE AF WOODS, BW PAYNE, SA MARION, JE HUGHES, RS DAVIS, LE TI THERMOMECHANICAL AND THERMOOPTIC PROPERTIES OF THE LICAALF6-CR3+ LASER MATERIAL SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID TUNABLE ALEXANDRITE LASERS; EXCITED-STATE ABSORPTION; ALKALI-HALIDE CRYSTALS; REFRACTIVE-INDEX; ND; POLARIZABILITIES; SPECTROSCOPY; PERFORMANCE; TEMPERATURE; GARNET AB Measurements of the intrinsic thermomechanical and thermo-optical properties of the new laser material LiCaAlF6:Cr3+ (known as Cr:LiCAF) are performed. Thermal diffusivity, heat capacity, thermal expansion, elastic constants, fracture toughness, and dispersion and temperature variation of the refractive index are all characterized for this material. In addition, the magnitude of the thermal lensing induced in a flash-lamp-pumped laser rod of Cr:LiCAF is measured and compared with the results obtained for an alexandrite laser rod in the same laser head. We find that the thermal lensing of Cr:LiCAF is favorably small and that the thermomechanical properties are expected to be adequate for applications at low and medium average power. RP WOODS, BW (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,POB 5508,LIVERMORE,CA 94550, USA. NR 44 TC 69 Z9 70 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 1991 VL 8 IS 5 BP 970 EP 977 DI 10.1364/JOSAB.8.000970 PG 8 WC Optics SC Optics GA FL116 UT WOS:A1991FL11600008 ER PT J AU KARR, TJ RUSHFORD, MC MURRAY, JR MORRIS, JR AF KARR, TJ RUSHFORD, MC MURRAY, JR MORRIS, JR TI MEASUREMENT OF THE STIMULATED THERMAL RAYLEIGH-SCATTERING INSTABILITY SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID LIGHT; TURBULENCE AB The first clear experimental demonstration, to our knowledge, is reported of large amplification of small-scale spatial perturbations by stimulated thermal Rayleigh scattering of a cw laser beam propagating through an absorbing medium in a context normally associated with thermal blooming. A single-mode argon-ion laser beam with lambda = 488 nm was propagated vertically downward through a 1.2-m cell filled with CCl4 that was doped with an absorber to have optical depths in the range 0.5-2.3. A shear-plate interferometer near the cell input generated the perturbation. Fringe growth was rapid and visually obvious, as was competing growth from dust specks, etc. The measured growth rate is in good agreement with the asymptotic rate from analytic stimulated thermal Rayleigh scattering theory. RP KARR, TJ (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,POB 808,L-495,LIVERMORE,CA 94550, USA. NR 29 TC 0 Z9 0 U1 1 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 1991 VL 8 IS 5 BP 993 EP 999 DI 10.1364/JOSAB.8.000993 PG 7 WC Optics SC Optics GA FL116 UT WOS:A1991FL11600012 ER PT J AU SHAW, MJ SHORE, BW AF SHAW, MJ SHORE, BW TI COLLISIONS OF COUNTERPROPAGATING OPTICAL SOLITONS SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID ULTRASHORT AB We present numerical simulations of colliding counterpropagating solitons traversing a relaxation-free atomic vapor. The collisions produce appreciable spatially localized inversion of the atomic population, even in the case of colliding solitary 2-pi hyperbolic-secant pulses. The energy deposited in the atoms and lost from the pulses determines the pulse widths, energies, and phase shifts of the postcollision pulses. This energy subsequently appears as fluorescence. We present results that illustrate the role of the residual atomic excitation energy on postcollisional solitary pulses. In addition, we show that for certain conditions a low-density medium is transparent to nonsolitary pi pulses. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP SHAW, MJ (reprint author), UNIV CALIF DAVIS,DEPT APPL SCI,LIVERMORE,CA 94550, USA. NR 10 TC 7 Z9 7 U1 1 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 1991 VL 8 IS 5 BP 1127 EP 1134 DI 10.1364/JOSAB.8.001127 PG 8 WC Optics SC Optics GA FL116 UT WOS:A1991FL11600031 ER PT J AU TODD, RD SIMPSON, EM KIM, K BERNAT, TP AF TODD, RD SIMPSON, EM KIM, K BERNAT, TP TI A GENERAL-METHOD FOR THE STABILITY ANALYSIS OF A UNIFORM LIQUID FUEL LAYER INSIDE A SPHERICAL-SHELL INERTIAL CONFINEMENT FUSION TARGET SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article ID HYDROGEN ISOTOPES; THERMAL-GRADIENT AB The formulation of a general method is presented for the stability analysis of the spherically shaped surface of a gas bubble inside a thin, finite, incompressible liquid layer of a ternary D-T mixture as found in a spherical cryogenic inertial confinement fusion target. A force balance on the liquid-vapor interface is performed to find the initial surface-tension gradient required to hold the liquid layer uniform. A node centered, finite volume, central difference formulation is then used to solve numerically the transient continuity, Navier-Stokes, and energy equations in the presence of a variety of nonaxisymmetric perturbations. The approach used in establishing the appropriate numerical procedures is described. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RP UNIV ILLINOIS, FUS TECHNOL LAB, URBANA, IL 61801 USA. NR 14 TC 2 Z9 2 U1 0 U2 2 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 EI 1520-8559 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD MAY-JUN PY 1991 VL 9 IS 3 BP 842 EP 847 DI 10.1116/1.577326 PN 1 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100092 ER PT J AU MERCANTI, D DE STASIO, G CIOTTI, MT CAPASSO, C NG, W RAYCHAUDHURI, AK LIANG, SH COLE, RK GUO, ZY WALLACE, J MARGARITONDO, G CERRINA, F UNDERWOOD, J PERERA, R KORTRIGHT, J AF MERCANTI, D DE STASIO, G CIOTTI, MT CAPASSO, C NG, W RAYCHAUDHURI, AK LIANG, SH COLE, RK GUO, ZY WALLACE, J MARGARITONDO, G CERRINA, F UNDERWOOD, J PERERA, R KORTRIGHT, J TI PHOTOELECTRON MICROSCOPY IN THE LIFE SCIENCES - IMAGING NEURON NETWORKS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article AB Photoemission techniques like electron spectroscopy for chemical analysis are the leading electronic probes in materials science-but their impact in the life sciences has been minimal. A critical problem is that the lateral resolution in ordinary photoemission does not exceed a few tenths of a millimeter. This space-averaged probe is nearly useless for most of the fundamental problems in biophysics and biochemistry, which deal with microstructures in the submicron range or smaller. This limit is being overcome with photoemission microscopes, such as our scanning instrument MAXIMUM. The first scanning photoelectron micrographs of a cellular system with submicron resolution are presented. Minute details of neuron networks are imaged on MAXIMUM, thereby opening the way to novel applications of photoemission in the life sciences. The details include individual neurons, axons, dendrites, and synapses, and composite large-area scanning micrographs were routinely produced with a lateral resolution of 0.5-mu-m. C1 CNR, ISM, I-00044 FRASCATI, ITALY. UNIV WISCONSIN, DEPT PHYS, MADISON, WI 53706 USA. UNIV WISCONSIN, DEPT ELECT & COMP ENGN, MADISON, WI 53706 USA. ECOLE POLYTECH FED LAUSANNE, INST PHYS APPL, ECUBLENS, SWITZERLAND. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB, CTR XRAY OPT, BERKELEY, CA 94720 USA. RP MERCANTI, D (reprint author), CNR, IST NEUROBIOL, VIALE MARX 15, I-00100 ROME, ITALY. RI Margaritondo, Giorgio/B-1367-2008; Gilbert, Pupa/A-6299-2010 OI Gilbert, Pupa/0000-0002-0139-2099 NR 14 TC 9 Z9 9 U1 0 U2 0 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD MAY-JUN PY 1991 VL 9 IS 3 BP 1320 EP 1322 DI 10.1116/1.577619 PN 2 PG 3 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300017 ER PT J AU HULBERT, SL KAO, CC GARRETT, RF BARTYNSKI, RA YANG, S WEINERT, M JENSEN, E ZEHNER, DM AF HULBERT, SL KAO, CC GARRETT, RF BARTYNSKI, RA YANG, S WEINERT, M JENSEN, E ZEHNER, DM TI A COMPARISON OF THE SURFACE ELECTRONIC-STRUCTURE OF TA(100) AND TAC(100) USING AUGER-PHOTOELECTRON COINCIDENCE SPECTROSCOPY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article ID CARBIDE AB We present N7 VV (4f7/2 5d 5d) Auger spectra from TaC(111) taken in time coincidence with photoemitted bulk and surface-shifted 4f7/2 core-level electrons, and compare these data with self-convolutions of calculated valence band d densities of states (SCDOS) for the surface (first) and bulk (exponential sum of second, fourth, and sixth subsurface) atomic layers of a 13-layer slab. The Ta 4f levels of TaC(111) and Ta(100) both exhibit large surface core level shifts, but of opposite sign. Therefore, we compare the TaC(111) data and calculations with analogous N7 VV Auger coincidence spectra and calculated SCDOS that we have previously published for Ta(100). The bulk Ta(100) and surface TaC(111) spectra show favorable agreement with the calculations; the surface Ta(100) and bulk TaC(111) spectra, on the other hand, exhibit marked disagreement with the calculations. These discrepancies are consistent with and provide added support for the presence of our proposed 1 surface-to-bulk (bulk-to-surface) interatomic Auger decay mode which adds a bulk (surface) contribution to the surface (bulk) Auger line shape of Ta(100) (TaC(111)). These conclusions are supported by comparison of our data to incoherent sums of bulk and surface SCDOS. C1 RUTGERS STATE UNIV, DEPT PHYS & ASTRON, PISCATAWAY, NJ 08855 USA. RUTGERS STATE UNIV, SURFACE MODIFICAT LAB, PISCATAWAY, NJ 08855 USA. BROOKHAVEN NATL LAB, DEPT PHYS, UPTON, NY 11973 USA. BRANDEIS UNIV, DEPT PHYS, WALTHAM, MA 02254 USA. OAK RIDGE NATL LAB, DIV SOLID STATE, OAK RIDGE, TN 37831 USA. RP BROOKHAVEN NATL LAB, NATL SYNCHROTRON LIGHT SOURCE, UPTON, NY 11973 USA. NR 13 TC 14 Z9 14 U1 0 U2 1 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 EI 1520-8559 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD MAY-JUN PY 1991 VL 9 IS 3 BP 1919 EP 1923 DI 10.1116/1.577544 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300125 ER PT J AU DESSAU, DS SHEN, ZX WELLS, BO SPICER, WE LIST, RS ARKO, AJ BARTLETT, RJ OLSON, CG MITZI, DB EOM, CB KAPITULNIK, A GEBALLE, TH AF DESSAU, DS SHEN, ZX WELLS, BO SPICER, WE LIST, RS ARKO, AJ BARTLETT, RJ OLSON, CG MITZI, DB EOM, CB KAPITULNIK, A GEBALLE, TH TI THE GOLD HIGH-TEMPERATURE SUPERCONDUCTOR INTERFACE - METALLICITY OF THE NEAR-SURFACE REGION AND A SEARCH FOR THE PROXIMITY EFFECT SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID CA-CU-O; ELECTRONIC-STRUCTURE; SINGLE-CRYSTAL; HEAT-TREATMENT; AG DEPOSITION; FILMS; STATE; PASSIVATION AB We have used high resolution photoemission spectroscopy to probe the electronic structure of a wide variety of gold/high temperature superconductor interfaces, the majority of which were formed by low-temperature (20 K) gold evaporations on cleaved high quality single crystals. For c-axis interfaces formed on the 123 family of superconductors, we fine that the gold deposition essentially destroys the metallicity of the superconducting substrate in the near surface region (approximately 5 angstrom), while the near surface region of Bi2Sr2CaCu2O8 remains metallic. We have also used photoemission spectroscopy to search for a proximity-effect induced superconducting gap in gold overlayers on c-axis single crystals and a-axis thin films, though no such effect was found. C1 UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. STANFORD UNIV,DEPT APPL PHYS,STANFORD,CA 94305. RP DESSAU, DS (reprint author), STANFORD UNIV,STANFORD ELECTR LABS,STANFORD,CA 94305, USA. RI Mitzi, David/B-6260-2012; Eom, Chang-Beom/I-5567-2014 OI Mitzi, David/0000-0001-5189-4612; NR 26 TC 2 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 383 EP 389 DI 10.1116/1.577418 PN 1 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100002 ER PT J AU ERDEMIR, A CHENG, CC AF ERDEMIR, A CHENG, CC TI EFFECT OF POSTDEPOSITION ANNEALING ON STRUCTURE AND CHEMISTRY OF THE TIN FILM STEEL SUBSTRATE INTERFACES SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID COATINGS AB This study deals with solid-state phase transformations occurring at interfaces between a TiN film and an AISI M50 steel substrate during postdeposition annealing at 500 and 1000-degrees-C. Cross-sectional transmission electron microscopy (XTEM) was used to investigate the nature of phase transformations at these interfaces. The TiN films were ion plated onto M50 steel with an initial Ti underlayer at 100-degrees-C. XTEM and electron energy loss spectroscopy of the interfaces indicated that the ion-plated Ti underlayers transformed into a TiC phase during annealing at 500-degrees-C and into a Ti(C,N) phase during annealing at 1000-degrees-C. In addition, the density of defects within grains was significantly reduced during annealing and the grains themselves became larger. C1 INLAND STEEL CORP,E CHICAGO,IN 46213. RP ERDEMIR, A (reprint author), ARGONNE NATL LAB,DIV MAT & COMPONENTS TECHNOL,ARGONNE,IL 60439, USA. NR 12 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 439 EP 443 DI 10.1116/1.577429 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100013 ER PT J AU BARBOUR, JC STEIN, HJ POPOV, OA YODER, M OUTTEN, CA AF BARBOUR, JC STEIN, HJ POPOV, OA YODER, M OUTTEN, CA TI SILICON-NITRIDE FORMATION FROM A SILANE NITROGEN ELECTRON-CYCLOTRON RESONANCE PLASMA SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC AB Good quality, low temperature silicon nitride and oxynitride films were deposited downstream from an electron cyclotron resonance (ECR) plasma source using SiH4 and N2 gas mixtures. The Si/N ratio and H content in the deposited films were determined using Rutherford backscattering spectrometry and elastic recoil detection. The H concentration was minimum for films with compositions closest to that of stoichiometric Si3N4. The optimum conditions for producing a stoichiometric Si3N4 were a SiH4/N2 flow ratio between 0.1 and 0.2, and an electrically isolated sample far from the ECR source. Infrared absorption spectra showed that as the film composition changed from N rich to Si rich the dominant bonds associated with H changed from N-H to Si-H. C1 MICROSCI INC,NORWELL,MA 02061. UNIV MICHIGAN,DEPT NUCL ENGN,ANN ARBOR,MI 48109. RP BARBOUR, JC (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 10 TC 58 Z9 58 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 480 EP 484 DI 10.1116/1.577392 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100020 ER PT J AU WACHS, AL BATES, JB DUDNEY, NJ LUCK, CF AF WACHS, AL BATES, JB DUDNEY, NJ LUCK, CF TI PLASMA DIAGNOSTIC STUDIES OF THE INFLUENCE OF PROCESS VARIABLES UPON THE ATOMIC AND MOLECULAR-SPECIES EJECTED FROM (1-X)LI4SIO4-XLI3PO4 TARGETS DURING RADIO-FREQUENCY MAGNETRON SPUTTERING SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC AB The deposition of thin-film electrolytes is a critical step in the development of lithium microbatteries with the potential for circuit integration. We have performed a preliminary study of the radio frequency-magnetron sputtering of (1 - x)Li4SiO4:xLi3PO4 targets used to deposit amorphous thin-film electrolytes formed of the three-component system Li2O-SiO2-P2O5. Mass and optical emission spectroscopies have been used to investigate the effects of target composition and the deposition conditions upon the atomic and molecular species ejected from the targets. The data provide important information for understanding the mechanism of film formation and for monitoring the Li atomic flux onto the substrates during film growth. RP WACHS, AL (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. RI Dudney, Nancy/I-6361-2016 OI Dudney, Nancy/0000-0001-7729-6178 NR 4 TC 6 Z9 6 U1 1 U2 11 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 492 EP 495 DI 10.1116/1.577394 PN 1 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100022 ER PT J AU ABOUELFOTOUH, FA KAZMERSKI, LL MOUTINHO, HR WISSEL, JM DHERE, RG NELSON, AJ BAKRY, AM AF ABOUELFOTOUH, FA KAZMERSKI, LL MOUTINHO, HR WISSEL, JM DHERE, RG NELSON, AJ BAKRY, AM TI DETERMINATION AND OBSERVATION OF ELECTRONIC DEFECT LEVELS IN CULNSE2 CRYSTALS AND THIN-FILMS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID SOLAR-CELLS; HETEROJUNCTIONS AB The effects of heat and surface treatments used in the fabrication of CuInSe2 (CIS) single-crystal and thin-film solar cells are investigated, and the associated dominant defect states are identified using high-resolution photoluminescence (PL) and deep-level transient spectroscopy (DLTS) measurements. The results are correlated with junction electrical characteristics, and comparisons between thin films and single crystals are established. For the first time, direct evidence for several major defect types (Cu vacancies, Cu at In sites, and In at Cu sites) responsible for the majority-carrier type of the CIS is presented based upon spectroscopic atomic imaging of the n- and p-type semiconductor surfaces. Radiative recombination levels of extrinsic origin resulting from the surface processing (including polishing, etching, and annealing) were detected in the near surface region of the CIS single crystals, but not in the thin-film material having the same composition. The energy locations and depth of these states are responsible for the formation of an interfacial layer that is confirmed from frequency-dependent capacitance-voltage (C-V) data. The DLTS measurements on single-crystal and thin-film heterostructure {i.e., [Cd,Zn]S/CIS} devices (of nearly identical chemical compositions) have also confirmed the presence of a dominant trap level in the 270-meV region above the valance band. However, the trap density is some two orders of magnitude lower in the thin-film device, giving evidence that this processing-related defect level is responsible for the inferior performance of the single-crystal solar cells. RP ABOUELFOTOUH, FA (reprint author), SOLAR ENERGY RES INST,GOLDEN,CO 80401, USA. NR 11 TC 30 Z9 30 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 554 EP 558 DI 10.1116/1.577408 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100036 ER PT J AU STEVENS, JE CECCHI, JL HUANG, YC JARECKI, RL AF STEVENS, JE CECCHI, JL HUANG, YC JARECKI, RL TI OPTIMIZED MICROWAVE COUPLING IN AN ELECTRON-CYCLOTRON RESONANCE ETCH TOOL SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID ECR ION-SOURCE; ELECTROMAGNETIC-WAVE; PLASMA AB We have improved the operational characteristics of an electron cyclotron resonance (ECR) plasma etch tool by optimizing the coupling of the 2.45-GHz microwaves to the plasma. Improved coupling is achieved by using a right-hand circularly polarized (r.h.c.p.) mode which is matched to the plasma impedance through a quarter-wave transformer. This design reduces microwave reflected power typically to < 5% of the incident power without external tuning and simplifies control of the plasma etch tool operation. The r.h.c.p. mode is azimuthally symmetric when averaged over one microwave cycle and adapts easily to ECR source chambers of larger radii. We present an analytic model, the results of which are in good agreement with our experiments for microwave coupling in ECR etch tools. C1 PRINCETON UNIV,DEPT CHEM ENGN,PRINCETON,NJ 08544. RP STEVENS, JE (reprint author), PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08544, USA. NR 21 TC 33 Z9 36 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 696 EP 701 DI 10.1116/1.577346 PN 1 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100066 ER PT J AU OUTTEN, CA BARBOUR, JC WAMPLER, WR AF OUTTEN, CA BARBOUR, JC WAMPLER, WR TI CHARACTERIZATION OF ELECTRON-CYCLOTRON RESONANCE HYDROGEN PLASMAS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID IONS AB Electron cyclotron resonance (ECR) plasmas yield low energy and high ion density plasmas. The characteristics downstream of an ECR hydrogen plasma were investigated as a function of microwave power and magnetic field. A fast-injection Langmuir probe and a carbon resistance probe were used to determine plasma potential (V(p)), electron density (N(e)), electron temperature (T(e)), ion energy (T(i)), and ion fluence. Langmuir probe results showed that, at 17 cm downstream from the ECR chamber, the plasma characteristics are approximately constant across the center 7 cm of the plasma, for 50 W of absorbed power. These results gave V(p) = 30 +/- 5 eV, N(e) = 1 X 10(8) cm-3, and T(e) = 10-13 eV. In good agreement with the Langmuir probe results, carbon resistance probes have shown that T(i) less-than-or-equal-to 50 eV. Also, based on hydrogen chemical sputtering of carbon, the hydrogen (ion and energetic neutrals) fluence rate was determined to be 1 X 10(16) /cm2 s at a pressure of 1 X 10(-4) Torr and for 50 W of absorbed power. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP OUTTEN, CA (reprint author), UNIV MICHIGAN,DEPT NUCL ENGN,ANN ARBOR,MI 48109, USA. NR 9 TC 25 Z9 25 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 717 EP 721 DI 10.1116/1.577350 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100070 ER PT J AU WALSH, DS DOYLE, BL WAMPLER, WR HAYS, AK AF WALSH, DS DOYLE, BL WAMPLER, WR HAYS, AK TI H-ISOTOPE RETENTION AND THERMAL ION-INDUCED RELEASE IN BORONIZED FILMS FOR THE TOKAMAK FUSION TEST REACTOR SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID DISCHARGE; DEUTERIUM; CARBON AB Over the past decade, it has been clearly demonstrated that the composition of the very near surface (approximately 100 nm) of plasma-interactive components plays a determinant role in most processes which occur in the plasma edge of tokamaks. Two very successful techniques to effect control of the plasma-wall interaction are (1) in-situ deposition of amorphous carbon or boron-carbon films and (2) the use of He/C conditioning discharges or He glow discharge cleaning to modify the near surface of bulk graphite components. We have deposited boronized layers onto Si using plasma-assisted chemical vapor deposition (CVD) and sputter deposition. The plasma-enhanced chemical vapor deposition (PCVD) deposition conditions were as close as possible to those used in the Tokamak Fusion Test Reactor (TFTR), and some films deposited in TFTR have also been studied. Using these two deposition techniques, B(x)CH(y) films have been produced with x varying from 1/2-4, and y from approximately 1 (sputtered) to approximately 3 (PCVD). Most films also contained significant amounts of O. Thermal and ion-induced release of H isotopes from BC films is qualitatively similar to that measured for graphite. Implanted H saturates in these films at an H/host atom ratio of 0 7 which is considerably higher than that of graphite (approximately 0.4). As-deposited PCVD films are already saturated with H, while sputtered films are not. Sputtered BC films therefore possess an inherent H-pumping capability which could prove to be extremely beneficial to TFTR. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP WALSH, DS (reprint author), IDAHO STATE UNIV,POCATELLO,ID 83209, USA. NR 15 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 727 EP 732 DI 10.1116/1.577352 PN 1 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100072 ER PT J AU LANGLEY, RA QUALLS, AL WILGEN, JB AF LANGLEY, RA QUALLS, AL WILGEN, JB TI ABSOLUTE CALIBRATION OF A FROZEN HYDROGEN PELLET MASS DETECTOR SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID INJECTION AB Fueling of plasma physics experiments by the injection of frozen hydrogenic pellets has been accomplished on many devices, including the Tokamak Fusion Test Reactor (TFTR), the Joint European Torus (JET), Tore Supra, and the Advance Toroidal Facility (ATF). Injection of pellets lead to density increases in the plasma with efficiencies varying from 50% to near 100%. Determination of the fueling efficiency requires knowledge of both the plasma density and the pellet mass. The pellet mass can be determined as the pellet passes through a microwave cavity by the change in power transmitted though the cavity. A one-to-one correspondence between the transmitted power and the pellet mass has been demonstrated, but this system must be calibrated by other techniques. The technique described here is measuring the pellet mass directly by measuring the pressure increase in a vacuum chamber into which the pellet is injected. A high-sensitivity capacitance manometer is used to absolutely measure the pressure profile pulse during pellet injection. Since these fuel pellets are hydrogenic, absorption of hydrogen onto the chamber wall must be accounted for in the calibration procedure. A fast (1 ms response time) pressure manometer allows measurement of the pressure pulse profile from which the absorption can be estimated, thereby allowing a determination of the pellet mass and a calibration of the microwave cavity technique. Results are presented and compared with other pellet size diagnostics. RP LANGLEY, RA (reprint author), OAK RIDGE NATL LAB,POB 2009,OAK RIDGE,TN 37831, USA. NR 9 TC 2 Z9 2 U1 2 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 737 EP 741 DI 10.1116/1.577354 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100074 ER PT J AU KILPATRICK, SJ PITCHER, CS DYLLA, HF MANOS, DM NYBERG, I RAMSEY, AT STRATTON, BC TIMBERLAKE, J ULRICKSON, MJ AF KILPATRICK, SJ PITCHER, CS DYLLA, HF MANOS, DM NYBERG, I RAMSEY, AT STRATTON, BC TIMBERLAKE, J ULRICKSON, MJ TI THE EFFECT OF LIMITER CONDITIONING ON THE TOKAMAK FUSION TEST REACTOR EDGE PLASMA SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID ENHANCED CONFINEMENT DISCHARGES; ION-INDUCED RELEASE; GRAPHITE; DEUTERIUM; HYDROGEN; CARBON; TFTR AB Measurements by moveable Langmuir probes and edge spectroscopy diagnostics have documented the conditioning effect of low-density helium-initiated discharge sequences on the Tokamak Fusion Test Reactor edge plasma. Langmuir probe measurements shown in general that the edge electron density n(e) decreases by less than a factor of 2 while the edge electron temperature T(e) doubles. Radial profiles to the plasma boundary show that the density scrape-off length increases somewhat while the temperature scrape-off length decreases substantially. The particle flux density is unaffected. The spectral emission of C II decreases by a factor of 2, a much smaller change than that exhibited by the D-alpha signal. These results complement previous accounts of the conditioning technique. Comparisons of these He conditioning measurements are made to edge measurements during a deuterium density scan experiment, showing many similarities, and to an existing edge model of the conditioning process, showing qualitative agreement. RP KILPATRICK, SJ (reprint author), PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 20 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 742 EP 746 DI 10.1116/1.577355 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100075 ER PT J AU YOUCHISON, DL NAHEMOW, MD MCGRATH, RT BARATTA, AJ AF YOUCHISON, DL NAHEMOW, MD MCGRATH, RT BARATTA, AJ TI THE ROLE OF SURFACE MICROSTRUCTURE IN THE SPUTTERING OF GRAPHITE SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID HYDROGEN; BEAMS AB Extensive exposure to tokamak plasmas may result in significant alterations to the surface microstructure of graphite plasma-facing components. A change in microstructure from a commercial isotropic graphite to an amorphous carbon film may produce a significant change in the total sputtering yield and the level of plasma contamination. To investigate this sensitivity to surface microstructure, sputtering experiments on a variety of graphites with various surface structures were performed using the ion-surface interaction system (ISIS).1 ISIS is a computerized ion beam sputtering system equipped with twin quartz crystal microbalances capable of simultaneously monitoring both sputtering and redeposition of the beam target material. ISIS was used to obtain sputtering data on two orientations of pyrolytic graphite at seven energies between 100 eV and 10 keV. Helium bombardment perpendicular to the prism plane produced yields 2 to 7 times higher than on the basal plane. Proton bombardment perpendicular to the prism plane produced yields 45% higher than those on the basal plane. Amorphous graphite films produced from Poco AXF-5Q and Union Carbide ATJ graphites using an argon radio-frequency (rf) plasma discharge were also irradiated. Sputtering yields on the amorphous films were as much as 50% to an order of magnitude higher than those measured on commercial bulk samples. Pre and post-irradiation scanning electron microscopy of selected targets was performed to monitor surface microstructure. A structural mechanism responsible for the magnitude of physical sputtering is suggested, and an effective surface binding energy is introduced to quantify this structural dependence. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP YOUCHISON, DL (reprint author), PENN STATE UNIV,DEPT NUCL ENGN,UNIVERSITY PK,PA 16802, USA. OI Youchison, Dennis/0000-0002-7366-1710 NR 10 TC 3 Z9 3 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 753 EP 758 DI 10.1116/1.577357 PN 1 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100077 ER PT J AU HIBBS, SM ALLEN, SL PETERSEN, DE SEWALL, NR AF HIBBS, SM ALLEN, SL PETERSEN, DE SEWALL, NR TI A FUEL PELLET INJECTOR FOR THE MICROWAVE TOKAMAK EXPERIMENT SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID PIPE GUN AB Unlike other fueling systems for magnetically confined fusion plasmas, a pellet injector can efficiently deliver fuel gas to the plasma core, enhancing plasma confinement. We installed a new pellet injector on the microwave tokamak experiment (MTX, formerly Alcator-C) to provide a plasma with a high core density for experiments both with and without ultrahigh-power microwave heating. Its four-barrel pellet generator is the first to be designed and built at Lawrence Livermore National Laboratory. Based on "pipe-gun" technology developed at Oak Ridge National Laboratory, it incorporates our structural and thermal engineering innovations and a unique control system. The pellet guide section, differential vacuum-pumping stages, and fast-opening propellant valves are reused parts of the Impurity Study Experiment (ISX) pellet injector built by ORNL. We tailored designs of all other systems and components to the MTX. Our injector launches pellets of frozen hydrogen or deuterium into the MTX, either singly or in times bursts of up to four pellets at velocities of up to 1 000 m/s. Pellet diameters at formation range from 1.02 to 2.08 mm. A diagnostic stage measures pellet velocities and allows us to photograph the pellets' flight. We are striving to improve the injector's performance, but its operation is already very consistent and reliable. RP HIBBS, SM (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551, USA. NR 9 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 835 EP 841 DI 10.1116/1.577325 PN 1 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100091 ER PT J AU LANGLEY, RA CRUME, EC GLOWIENKA, JC HORTON, LD ISLER, RC MURAKAMI, M SIMPKINS, JE AF LANGLEY, RA CRUME, EC GLOWIENKA, JC HORTON, LD ISLER, RC MURAKAMI, M SIMPKINS, JE TI EFFECTS OF WALL CONDITIONING ON PLASMA PERFORMANCE IN THE ADVANCED TOROIDAL FACILITY STELLARATOR SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC AB Various wall conditioning techniques have been used on the Advanced Toroidal Facility (ATF). Continued improvement in plasma parameters has been obtained. In ATF, a stellarator, wall conditioning is more important for obtaining favorable plasma parameters than it is in plasma devices with current. Discharge cleaning, baking, and gettering with both chromium and titanium have been used as conditioning techniques. Gettering with titanium has increased the pumping speed of nitrogen and oxygen by more than a factor of 10, significantly reducing impurity effects, and has allowed better control over wall recycling and thereby plasma density. This has increased the operating space for many of the plasma parameters. The effects of these conditioning techniques on plasma parameters are discussed. RP LANGLEY, RA (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. OI Isler, Ralph/0000-0002-5368-7200 NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 848 EP 851 DI 10.1116/1.577327 PN 1 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100093 ER PT J AU TOBIN, JG COLVIN, VL ALIVISATOS, AP AF TOBIN, JG COLVIN, VL ALIVISATOS, AP TI PHOTOEMISSION INVESTIGATION OF COMPOUND SEMICONDUCTOR MONODISPERSE CLUSTERS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC AB We have used synchrotron radiation photoemission to probe the valence and core level electronic structure of compound-semiconductor monodisperse clusters (nanocrystals). These clusters exhibited a 10% or less variation relative to the mean diameter and were attached to the metal substrates via alkane chains. Direct evidence of gap broadening due to size variation in CdS clusters was observed. The novel utilization of alkane chain attachment is the key to eliminating the otherwise debilitating problem of sample charging, as occurs with powders. The quality of sample preparation was confirmed by other methods such as transmission electron microscopy, Raman scattering, and x-ray diffraction. This work provides a direct link between photoemission studies of expitaxial ultrathin films of compound semiconductors, the photon-spectroscopy measurements of cluster powders and the existing theories of quantum confinement in reduced dimensionality structures. C1 UNIV CALIF BERKELEY,BERKELEY,CA 94720. RP TOBIN, JG (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551, USA. RI Tobin, James/O-6953-2015; Alivisatos , Paul /N-8863-2015 OI Alivisatos , Paul /0000-0001-6895-9048 NR 4 TC 8 Z9 8 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 852 EP 853 DI 10.1116/1.577328 PN 1 PG 2 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100094 ER PT J AU NELSON, AJ GEBHARD, S KAZMERSKI, LL COLAVITA, E ENGELHARDT, M HOCHST, H AF NELSON, AJ GEBHARD, S KAZMERSKI, LL COLAVITA, E ENGELHARDT, M HOCHST, H TI FORMATION AND SCHOTTKY-BARRIER HEIGHT OF AU CONTACTS TO CUINSE2 SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID ELECTRONIC-STRUCTURE; SINGLE-CRYSTALS; SOLAR-CELLS; PHOTOEMISSION; INTERFACES; CUGASE2 AB Synchrotron radiation soft x-ray photoemission spectroscopy was used to investigate the development of the electronic structure at the Au/CuInSe2 interface. Au overlayers were deposited in steps on single-crystal p and n-type CuInSe2 at ambient temperature. Reflection high-energy electron diffraction analysis before and during growth of the Au overlayers indicated that the Au overlayer was amorphous. Photoemission measurements were acquired after each growth in order to observe changes in the valence band electronic structure as well as changes in the In 4d and Se 3d core lines. The results were used to correlate the interface chemistry with the electronic structure at these interfaces and to directly determine the Au/CuInSe2 Schottky barrier height. C1 UNIV CALABRIA,DEPT PHYS,I-87036 RENDE,ITALY. UNIV WISCONSIN,CTR SYNCHROTRON RADIAT,STOUGHTON,WI 53589. RP NELSON, AJ (reprint author), SOLAR ENERGY RES INST,GOLDEN,CO 80401, USA. NR 23 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 978 EP 982 DI 10.1116/1.577559 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100118 ER PT J AU RYE, RR AF RYE, RR TI HOT FILAMENT ACTIVATED CHEMICAL VAPOR-DEPOSITION OF BORON-NITRIDE SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID HYDROGENATED AMORPHOUS-SILICON; LOW-TEMPERATURE DEPOSITION; PRESSURE PYROLYSIS; BN FILMS; BORAZINE AB Using a hot filament (almost-equal-to 1400-degrees-C) to activate borazine (B3N3H6) molecules for subsequent reaction with a direct line-of-sight substrate, transparent boron nitride films as thick as 25 000 angstrom have been grown for substrate temperatures as low as 100-degrees-C. The minimum temperature is determined by radiative heating from the adjacent hot filament. The low temperature BN films show no indication of crystallinity with x-ray diffraction (XRD), but the opaque BN deposit produced on the hot filament is identified by XRD as polycrystalline h-BN. X-ray photoelectron spectra (XPS) show the films to have a B:N ratio (within experimental error) of 1:1 with no other XPS detectable impurities above the 0.5% level. Both Raman and infrared (IR) spectroscopy are characteristic of h-BN with small amounts of hydrogen detected as N-H and B-H bands in the IR spectrum. The important feature of this method is the separation and localization of the thermal activation step at the hot filament from the surface reaction and film growth steps at the substrate surface. This allows both higher temperature thermal activation and lower temperature film growth. RP RYE, RR (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 18 TC 18 Z9 18 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1099 EP 1103 DI 10.1116/1.577583 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100141 ER PT J AU YANG, XQ RUCKMAN, MW SKOTHEIM, TA DENBOER, M ZHENG, Y BADZIAN, AR BADZIAN, T MESSIER, R SRIVATSA, AR AF YANG, XQ RUCKMAN, MW SKOTHEIM, TA DENBOER, M ZHENG, Y BADZIAN, AR BADZIAN, T MESSIER, R SRIVATSA, AR TI X-RAY ABSORPTION STUDY OF DIAMOND FILMS GROWN BY CHEMICAL VAPOR-DEPOSITION SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID CARBON-K-EDGE; FINE-STRUCTURE; THIN-FILMS; GRAPHITE; SPECTROSCOPY; STATES; CVD AB Carbon k-edge x-ray absorption fine structure (XAFS) is used to study the structure and bonding of chemical vapor deposition (CVD) grown diamond and diamond-like carbon films. Diamond films grown at 875-degrees-C on silicon using a 1% CH4/H2 mixture have near-edge spectra resembling type 1 (a) natural diamond. The k-edges of the diamond-like films grown by electron cyclotron resonance CVD at 200-degrees-C using 10(-4) Torr of CH4 show a broad main peak lacking the sharp structure of graphite or diamond. Comparing the near edges of the CVD diamond film with other carbon compounds (i.e., graphite) and the CVD diamond film, the diamond-like film shows a strong pi* feature at 285 eV indicative of sp2 bonded carbon and a feature at 289 eV, the sigma*(C-H) resonance indicating C-H bonds. The relatively weak extended x-ray absorption fine structure (EXAFS) shows that the diamond-like carbon film is highly disordered on an atomic level. C1 CUNY,NEW YORK,NY 10021. PENN STATE UNIV,UNIVERSITY PK,PA 16802. MOLTECH CORP,STONY BROOK,NY 11974. RP YANG, XQ (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 28 TC 9 Z9 10 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1140 EP 1144 DI 10.1116/1.577591 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100149 ER PT J AU VANDENTOP, GJ KAWASAKI, M KOBAYASHI, K SOMORJAI, GA AF VANDENTOP, GJ KAWASAKI, M KOBAYASHI, K SOMORJAI, GA TI THE EFFECT OF ION ENERGY FLUX ON THE PROPERTIES OF HYDROGENATED AMORPHOUS-CARBON FILMS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC AB In this study the effect of varying ion energy flux on the properties of amorphous hydrogenated carbon films produced by plasma-assisted chemical vapor deposition from methane was investigated. The ion current, used to calculate the apparent ion energy flux, was measured through an orifice in one of the electrodes of the parallel plate system, using a Faraday cup. The film properties investigated include hardness, stress, methyl and methylene concentrations, and optical gap. All the observed properties vary significantly with ion energy flux and are strongly correlated with each other. As ion energy flux increases, the hardness increases, the compressive stress increases, the concentration of methyl and methylene groups decrease, and the optical gap decreases. The results demonstrate how the ion energy flux on to the film surface controls the final properties of the films. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RP VANDENTOP, GJ (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT SCI,CTR ADV MAT,BERKELEY,CA 94720, USA. NR 11 TC 23 Z9 23 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1157 EP 1161 DI 10.1116/1.577594 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100152 ER PT J AU JANKOWSKI, AF SCHRAWYER, LR PERRY, PL AF JANKOWSKI, AF SCHRAWYER, LR PERRY, PL TI REACTIVE SPUTTERING OF MOLYBDENUM-OXIDE GRADIENT-INDEX FILTERS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID THIN AB Molybdenum-oxide gradient-index films are produced by reactive sputter deposition. A molybdenum metal target is sputtered continuously with an argon-oxygen gas mixture. For each target power used, a reproducible oxide composition and corresponding refractive index result. Repetitive variation of applied target power is used to produce a structure composed of discrete layers of preselected stoichiometry. The systematic control of a single process parameter, target power, simplifies the fabrication of molybdenum-oxide rugate filters. RP JANKOWSKI, AF (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 12 TC 9 Z9 10 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1184 EP 1187 DI 10.1116/1.577599 PN 1 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR761 UT WOS:A1991FR76100157 ER PT J AU CAPASSO, C RAYCHAUDHURI, AK NG, W LIANG, S COLE, RK WALLACE, J CERRINA, F MARGARITONDO, G UNDERWOOD, JH KORTRIGHT, JB PERERA, RCC AF CAPASSO, C RAYCHAUDHURI, AK NG, W LIANG, S COLE, RK WALLACE, J CERRINA, F MARGARITONDO, G UNDERWOOD, JH KORTRIGHT, JB PERERA, RCC TI HIGH-RESOLUTION X-RAY MICROSCOPY USING AN UNDULATOR SOURCE, PHOTOELECTRON STUDIES WITH MAXIMUM SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID SYNCHROTRON-RADIATION; PHOTOEMISSION SPECTROMICROSCOPY; SURFACE; ALADDIN AB We present the first results of high-spatial resolution x-ray imaging studies with an upgraded version of the scanning photoemission multiple application x-ray imaging undulator microscope. The microscope is a multilayer coated Schwarzschild objective that focuses undulator radiation onto the sample. The recent upgrade improved the spatial resolution by a factor six reaching a full width at half maximum value of 0.5-mu-m. Highly polished mirrors reduced the diffuse background by almost two orders of magnitude and drastically improved the contrast. The improved microscope was used to perform a series of tests on microgrids and reverse Fresnel zone plates. The microscope capability to detect chemical and topological contrast was verified by using patterned metal overlayers on Si and GaAs substrates. Further improvements to increase the flux and the spatial resolution are underway; this includes the installation of a new undulator beamline. C1 ECOLE POLYTECH FED LAUSANNE,INST PHYS APPL,CH-1007 LAUSANNE,SWITZERLAND. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CTR XRAY OPT,BERKELEY,CA 94720. RP CAPASSO, C (reprint author), UNIV WISCONSIN,CTR XRAY LITHOG,3731 SCHNEIDER DR,STOUGHTON,WI 53589, USA. RI Margaritondo, Giorgio/B-1367-2008 NR 24 TC 36 Z9 36 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1248 EP 1253 DI 10.1116/1.577607 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300005 ER PT J AU ARLINGHAUS, HF THONNARD, N SPAAR, MT SACHLEBEN, RA BROWN, GM FOOTE, RS SLOOP, FV PETERSON, JR JACOBSON, KB AF ARLINGHAUS, HF THONNARD, N SPAAR, MT SACHLEBEN, RA BROWN, GM FOOTE, RS SLOOP, FV PETERSON, JR JACOBSON, KB TI COMPARISON OF SPUTTER-INITIATED RESONANCE IONIZATION SPECTROSCOPY AND LASER ATOMIZATION RESONANCE IONIZATION SPECTROSCOPY TO LOCALIZE TIN-LABELED DEOXYRIBOSE NUCLEIC-ACID SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID DNA AB Resonance ionization spectroscopy (RIS) is becoming recognized as an emerging field with wide applications. RIS is an analytical technique providing extreme element sensitivity and selectivity by detecting ionization produced from lasers tuned to excited states of the analyte. Using either sputter-initiated RIS (SIRIS) or laser atomization RIS (LARIS), it is possible to localize and quantify with micrometer spatial resolution ultratrace concentrations of a selected element at or near the surface of solid samples. The sensitivity and selectivity of the RIS process is especially valuable for trace element analysis in biological media, where the complexity of the matrix is frequently a serious source of interference. We have compared both the SIRIS and LARIS technique to determine their characteristics to localize and quantify Sn-labeled deoxyribose nucleic acid (DNA). We will present (a) data showing differences between SIRIS and LARIS response as a function of atomization parameter, substrate and analyte, and (b) the detection and resolution (spatial and isotopic) of subattomole quantities of Sn-labeled DNA bands. Both techniques have the potential of making a strong contribution to DNA sequencing. C1 OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831. UNIV TENNESSEE,GRAD SCH BIOMED SCI,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. RP ARLINGHAUS, HF (reprint author), ATOM SCI INC,OAK RIDGE,TN 37830, USA. RI Sloop, Jr., Frederick/J-2301-2016 OI Sloop, Jr., Frederick/0000-0001-6473-9507 NR 11 TC 16 Z9 16 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1312 EP 1319 DI 10.1116/1.577618 PN 2 PG 8 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300016 ER PT J AU WAMPLER, WR AF WAMPLER, WR TI THE INFLUENCE OF SURFACE OXYGEN ON UPTAKE AND RELEASE OF DEUTERIUM BY TANTALUM SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID HYDROGEN ABSORPTION; LIMITED RELEASE; UPTAKE RATES; NB; TA; OVERLAYERS; KINETICS; LAYERS; METALS; IRON AB Here we examine the influence of surface oxygen on both the absorption of deuterium (D) from gas into solution in tantalum (Ta) and the release from solution back to the gas. The D uptake rate was proportional to gas pressure with a sticking coefficient of 0.0085 +/- 0.0025 for clean Ta surfaces. Exposure to 10 Langmuirs (L) of O2, giving about one monolayer of chemisorbed oxygen, decreased the D uptake rate by about two orders of magnitude. D release was studied using the D (He-3,p) alpha-nuclear reaction to measure the concentration of D in the Ta versus time during release at constant temperature. D release was surface-limited and obeyed second-order kinetics for both clean and oxygen-covered Ta surfaces. The second-order kinetics show that D recombines from sites which are not saturated and therefore must have a smaller binding energy than the low-coverage chemisorption sites. Exposure to 10(6) L of O2 resulted in an additional energy barrier to D recombination of 0.25 +/- 0.04 eV/D which greatly reduces the D release rate. This activation barrier should also reduce D dissociation and uptake rates, and this is observed. The measured uptake and release rates are consistent with detailed balance. RP WAMPLER, WR (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 17 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1334 EP 1339 DI 10.1116/1.577622 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300020 ER PT J AU BAER, DR LANNUTTI, SM AF BAER, DR LANNUTTI, SM TI EFFECTS OF SULFUR ON VAPOR AND LIQUID H2O ADSORPTION ON STAINLESS-STEEL SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID SINGLE-CRYSTAL SURFACES; IRON-ALLOYS; WATER; AUGER; SPECTROSCOPY; DISSOLUTION; CHEMISTRY; NICKEL; OXYGEN; PLANE AB This paper reports a study of the influence of surface S on the adsorption of water vapor and liquid on an 18% Cr, 8% Ni austenitic stainless steel at room temperature. X-ray photoelectron spectroscopy measurements of the increase of O as a function of water exposure indicate that S inhibits water vapor uptake in direct relation to the amount of S on the surface, up to coverages almost-equal-to 0.8 monolayer. Higher S coverages did not further inhibit water uptake. In contrast, one monolayer of S on the surface did not significantly alter the thickness or composition of films formed in pure liquid water at 25-degrees-C. Exposure of the S-dosed steel to H2O water vapor or liquid produced no observable change in the S 2p photopeak. RP BAER, DR (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. RI Baer, Donald/J-6191-2013 OI Baer, Donald/0000-0003-0875-5961 NR 28 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1368 EP 1373 DI 10.1116/1.577629 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300027 ER PT J AU PEDEN, CHF KIDD, KB SHINN, ND AF PEDEN, CHF KIDD, KB SHINN, ND TI METAL METAL-OXIDE INTERFACES - A SURFACE SCIENCE APPROACH TO THE STUDY OF ADHESION SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID SINGLE-CRYSTAL SURFACES; THIN FE FILMS; ELECTRONIC-STRUCTURE; MODEL CATALYSTS; CU; ADSORPTION; OXYGEN; GROWTH; W(110); W(100) AB Metal-oxide/metal interfaces play an important role, for example, in the joining of an oxide ceramic to a metal for sealing applications. In order to probe the chemical and physical properties of such an interface, we have performed Auger electron spectroscopic (AES) and temperature programed desorption (TPD) experiments on a model system composed of very thin films of Cr, Fe, Ni, or Cu evaporated onto a very thin thermally grown oxide on a W single crystal. Monolayer films of Fe and Cr were found (by AES) to completely wet the oxide surface upon deposition, and were stable up to temperatures at which the films desorbed (almost-equal-to 1300 K). In contrast, monolayer Ni and Cu films formed three-dimensional islands exposing the oxidized W surface either upon annealing (Ni) or even upon room-temperature deposition (Cu). The relative interfacial interaction between the overlayer metal and the oxide, as assessed by TPD, increases in the series Cu < Ni < Fe < Cr. This trend follows the heats of formation of the various oxides of these metals. RP PEDEN, CHF (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 45 TC 75 Z9 75 U1 2 U2 18 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1518 EP 1524 DI 10.1116/1.577656 PN 2 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300054 ER PT J AU ZUO, JK WENDELKEN, JF AF ZUO, JK WENDELKEN, JF TI DEFECT AND IMPURITY EFFECTS ON THE INITIAL GROWTH OF AG ON SI(111) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID SCANNING TUNNELING MICROSCOPY; SURFACE-STRUCTURE; DOMAIN-GROWTH; DIFFRACTION; OVERLAYER; GEOMETRY; STEPS; AES AB Step and impurity effects on the initial growth of a thin film have been demonstrated in the (square-root 3 x square-root 3)R 30-degrees (or simply square-root 3) domain growth of Ag on Si(111) using high angular resolution low-energy electron diffraction. Anisotropy in the square-root 3 domain shape and growth during deposition are found on the stepped Si(111) with the preferential growth along the step edge direction. The square-root 3 superlattice grows with coverage principally by domain coalescence at the temperature T approximately 450-degrees-C and is self-similar at different coverages (scaling) as observed on a flat Si(111). The size distribution is shown to follow a Gamma distribution by a simple model calculation. A dramatic change in the growth mechanism is observed when oxygen impurities [less-than-or-equal-to 0.02 monolayer] appear. The square-root 3 domains in the presence of impurities grow with coverage more randomly and isotropically in contrast with the step edge effects and coalescence is inhibited. As a result, the square-root 3 superlattice stays in a microdomain morphology without long range order. RP ZUO, JK (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. NR 26 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1539 EP 1544 DI 10.1116/1.577658 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300057 ER PT J AU CHASON, E DODSON, BW AF CHASON, E DODSON, BW TI EFFECT OF STEP EDGE TRANSITION RATES AND ANISOTROPY IN SIMULATIONS OF EPITAXIAL-GROWTH SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID SCANNING TUNNELING MICROSCOPY; SURFACES; SI(001); STRINGS; MBE AB The results of a hybrid rate equation/Monte Carlo simulation of epitaxial growth on vicinal surfaces is presented. The effect on surface morphology of changing transition rates at step edges, of changing detachment rates from step edges and clusters, and of adding anisotropy to the diffusion and incorporation kinetics at step edges and islands was studied. The effect of the transition rates on surface morphology are discussed in terms of a balance between growth by nucleation and coalescence of islands and by the propagation of steps. RP CHASON, E (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 11 TC 33 Z9 33 U1 2 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1545 EP 1550 DI 10.1116/1.577659 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300058 ER PT J AU SHINN, ND TSANG, KL AF SHINN, ND TSANG, KL TI STRAIN-INDUCED SURFACE REACTIVITY - LOW-TEMPERATURE CR/W(110) NITRIDATION SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID ANGLE-RESOLVED PHOTOEMISSION; MOLECULAR NITROGEN; CHEMISORPTION; DISSOCIATION; ADSORPTION; FE(111); N-2; PRECURSOR; W(110); N2 AB Synchrotron photoelectron and Auger electron spectroscopies have been used to study the reaction of nitrogen with ultrathin chromium overlayers vapor deposited on W(110). Molecular nitrogen dissociates via a metastable pi-bonded intermediate on Cr(110), the strained (1 x 1) Cr/W(110) monolayer and the (2 x 2) Cr/W(110) bilayer surfaces. However, the activation energy for dissociation of the pi-bonded intermediate is lower on the strained overlayers than on Cr(110). This has been exploited to grow ultrathin CrN layers on W(110), which are spectroscopically indistinguishable from chromium nitride formed by reacting atomic Cr and N2 simultaneously on W(110) at 300 K. This demonstrates that nitridation proceeds via energetically equivalent pathways at isolated Cr adatoms on W(110) and at majority sites on the strained Cr/W(110) overlayers. In addition, an anomalous narrow band of states near the Fermi level is found for these surface nitrides and, tentatively, is attributed to unique surface or interface states of CrN:W(110). These findings suggest that strained pseudomorphic overlayers may be useful templates for low temperature nitride film growth. RP SHINN, ND (reprint author), SANDIA NATL LABS,DIV SURFACE SCI 1114,ALBUQUERQUE,NM 87185, USA. NR 32 TC 52 Z9 52 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1558 EP 1562 DI 10.1116/1.577661 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300060 ER PT J AU HILDNER, ML DALEY, RS FELTER, TE ESTRUP, PJ AF HILDNER, ML DALEY, RS FELTER, TE ESTRUP, PJ TI ION-SCATTERING STUDY OF THE RECONSTRUCTION OF MO(100) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID PHASE-TRANSITION; W(001) SURFACE; MO(001); W(100) AB High energy ion scattering (HEIS) is used to study the clean and hydrogen induced surface reconstructions on Mo(100) at low temperature (80 and 10 K). In conjunction with computer modeling, lateral displacements of 0.12 +/- 0.02 angstrom along the <11> direction and a first-layer inward relaxation of 0.11 +/- 0.03 angstrom for the clean reconstruction are measured. It is also established that the hydrogen saturated surface is bulk-like. In addition the HEIS results, combined with new low-energy electron diffraction data, indicate that even at temperatures as low as 10 K, hydrogen dissociates and diffuses on the surface and, at saturation coverage, quenches the reconstruction. C1 SANDIA NATL LABS,LIVERMORE,CA 94551. RP HILDNER, ML (reprint author), BROWN UNIV,PROVIDENCE,RI 02912, USA. NR 20 TC 22 Z9 22 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1604 EP 1609 DI 10.1116/1.577668 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300067 ER PT J AU SHEK, ML HRBEK, J SHAM, TK XU, GQ AF SHEK, ML HRBEK, J SHAM, TK XU, GQ TI THE EARLY STAGES IN THE OXIDATION OF NA SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID X-RAY; OXYGEN; PHOTOEMISSION; METAL; OVERLAYERS; ADSORPTION; RU(001); OXIDES AB We report soft x-ray photoemission results on the early stages of the oxidation of Na at approximately 80 K. The first stage (up to greater-than-or-similar-to 0.5 L exposure) is characterized by a narrow O 2p level and a Na 2p surface core level shifted by - 0.55 eV with respect to the bulk core level. The Na 2p surface plasmon loss intensity shifts toward smaller energies, consistent with a decrease in surface conduction electron density. The second stage (starting from approximately 1 L), is characterized by the emergence of "di-oxygen" valence levels and a Na 2p component shifted by approximately 0.8 eV with respect to the bulk binding energy. The oxidation is strongly nonuniform, as suggested by the small oxygen doses needed for the onset of the second oxidation stage, and the continued presence of the bulk plasmon loss from metallic Na. The two new Na 2p binding energies are tentatively attributed to different final-state screening of metallic Na adjacent to dispersed oxygen atoms in the first stage, and of the Na atoms with mostly oxygen nearest neighbors in the second stage. Observations regarding large negative core level shifts upon large oxygen exposures are also summarized. C1 BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. UNIV WESTERN ONTARIO,DEPT CHEM,LONDON N6A 5B7,ONTARIO,CANADA. RI Xu, Guo Qin/C-2077-2013; Hrbek, Jan/I-1020-2013 NR 16 TC 7 Z9 7 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1640 EP 1644 DI 10.1116/1.577478 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300073 ER PT J AU QIU, SL RUCKMAN, MW STRONGIN, M AF QIU, SL RUCKMAN, MW STRONGIN, M TI NEAR-EDGE AND PHOTOEMISSION-STUDIES OF THE INTERACTION OF CESIUM WITH AMMONIA AT 80-K SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID PHOTOELECTRON EMISSION; ELECTRONIC-STRUCTURE; SOLVATED ELECTRONS; SHAPE RESONANCES; SPECTROSCOPY; MOLECULES; PHOTOIONIZATION; ADSORPTION; SPECTRUM; NH3 AB A change in the electronic structure of ammonia when Cs is added is identified using combined soft x-ray absorption and photoemission measurements. Depositing Cs into an NH3 film retained at 80 K causes the formation of new valence band features at -4.8 or -5.5 eV binding energy and a reduction in the intensity of the N K-edge feature (related to Rydberg transitions involving the unoccupied 4a1 and 2e NH3 orbitals). A shift of the Cs 4d core level -2.8 eV to a greater binding energy suggests the transfer of charge from Cs to NH3. When ammonia is absorbed on a cesium film, similar changes are seen in the NH3 valence band photoemission and near-edge features. RP QIU, SL (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 32 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1645 EP 1649 DI 10.1116/1.577479 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300074 ER PT J AU BLUM, B PLUMMER, EW DAVIS, HL ZEHNER, DM AF BLUM, B PLUMMER, EW DAVIS, HL ZEHNER, DM TI BISMUTH INDUCED STRUCTURES ON COPPER(100) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID GRAIN-BOUNDARY SEGREGATION; ALLOYS; BI; DEPOSITION; SUBSTRATE; LEED AB Different submonolayer phases of bismuth on copper (100) have been investigated with low-energy electron diffraction and Auger electron spectroscopy. The room temperature observations, made after deposition Bi onto well annealed Cu, agreed with those reported previously. Below room temperature, a low coverage c(2 x 4) phase was observed. With increasing Bi coverage, this phase was observed to coexist with the c(2 x 2) phase, until finally, only the c(2 x 2) phase was observed. Restructuring of the Cu substrate into {210} facets, at 26-degrees-34' angle with the original (100) surface, was obtained by depositing Bi onto roughened Cu(100), and subsequently annealing. A possible explanation for the nucleation and growth of these facets is given. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP BLUM, B (reprint author), UNIV PENN,PHILADELPHIA,PA 19104, USA. NR 14 TC 8 Z9 8 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1703 EP 1706 DI 10.1116/1.577490 PN 2 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300085 ER PT J AU MALIK, IJ HRBEK, J AF MALIK, IJ HRBEK, J TI RU3 (CO)12 AND MO(CO)6 OVERLAYERS ADSORBED ON RU(001) AND AU/RU AND THEIR INTERACTION WITH ELECTRONS AND PHOTONS - AN INFRARED REFLECTION ABSORPTION STUDY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID SOLID-STATE; SURFACES; CO; PHOTOCHEMISTRY; SPECTROSCOPY; VIBRATIONS; RU3(CO)12; CARBONYLS; CLUSTERS; FE(CO)5 AB We studied adsorbed Ru3 (CO)12 and Mo (CO)6 overlayers on Ru(001) and Au/Ru surfaces by infrared reflection-absorption spectroscopy (IRAS) and thermal desorption spectroscopy (TDS). We characterized the C-O stretching mode of both metal carbonyls (4 cm-1 FWHM) and a deformation mode of Mo (CO)6 at 608 cm-1 with an unusually narrow FWHM of 1 cm-1. Both IRAS and TDS data suggest adsorption and desorption of metal carbonyls as molecular species with a preferential orientation in the overlayers. We discuss annealing experiments of Ru3 (CO)12/Ru(001), the interaction of Ru3 (CO)12 overlayers with electrons of up to 100-eV energy, and the interaction of Mo (CO)6 overlayers with 300-nm photons. RP MALIK, IJ (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. RI Hrbek, Jan/I-1020-2013 NR 24 TC 7 Z9 7 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1737 EP 1741 DI 10.1116/1.577496 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300091 ER PT J AU KELLOGG, GL WRIGHT, AF DAW, MS AF KELLOGG, GL WRIGHT, AF DAW, MS TI SURFACE-DIFFUSION AND ADATOM-INDUCED SUBSTRATE RELAXATIONS OF PT, PD, AND NI ATOMS ON PT(001) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID METAL-SURFACES AB Field ion microscope observations show that Pt atoms diffuse on Pt(001) by an adatom-substrate atom replacement mechanism, whereas Pd atoms diffuse on the same surface by site-to-site hopping. Ni adatoms are observed to exchange with substrate Pt(001) atoms at temperatures lower than the onset of their migration. The propensity for adatom-substrate atom exchange is found to be correlated with the amount of adatom-induced substrate relaxation. These relaxations are determined from calculations based on the embedded atom method. C1 SANDIA NATL LABS,LIVERMORE,CA 94551. RP KELLOGG, GL (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. RI Felfer, Peter/H-6024-2011 NR 12 TC 41 Z9 41 U1 2 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1757 EP 1760 DI 10.1116/1.577457 PN 2 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300096 ER PT J AU ORLANDO, TM BURNS, AR STECHEL, EB JENNISON, DR AF ORLANDO, TM BURNS, AR STECHEL, EB JENNISON, DR TI RESONANCE IONIZATION DETECTION OF NEUTRAL O(3PJ) PRODUCED FROM STIMULATED SURFACE PROCESSES SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID NITROGEN-DIOXIDE; MOLECULAR-OXYGEN; PT(111) SURFACE; ATOMIC OXYGEN; DESORPTION; PHOTOCHEMISTRY; O-2; DISSOCIATION; SPECTROSCOPY; PD(111) AB We report the first quantum-state specific detection of ground-state atomic oxygen O(3P(J) above an electron irradiated adsorbate-covered surface using laser resonance-enhanced multiphoton ionization spectroscopy. Electron-stimulated desorption of O(3P(J)) is not observed from an O-covered Pt(111) surface, but O(3P(J)) fragments are produced from electron-stimulated dissociation of NO2(a) coadsorbed with O theta-o = 0.75 ML) on Pt(111). The approximately 9-10 eV threshold for O(3P(J)) formation correlates with that observed for NO2(a) dissociation. The measured O(3P(J)) spin-orbit state distribution is (5.0):(2.5):(1.0) for J = 2, 1, and 0, respectively. This is within experimental error of the 2J + 1 statistical (T --> infinity) limit. No gas phase O(3P(J)) is detected from the stimulated dissociation of adsorbed O2 on Pt(111); however, we have utilized the O(3P(J)) detection capability as an indirect probe of NO2 production from an electron-stimulated surface reaction between coadsorbed O2 and NO on Pt(111). The NO2 is detected by laser photolysis above the surface. The approximately 10-eV NO2 production threshold correlates with dissociative ionization from the 3-sigma-g molecular bonding orbital of O2(a). Dissociative ionization can produce energetic O atoms which may then react with a coadsorbed NO, producing an NO2 desorbate. RP ORLANDO, TM (reprint author), SANDIA NATL LABS,DIV 1151,ALBUQUERQUE,NM 87185, USA. RI Stechel, Ellen/B-1253-2012 NR 31 TC 9 Z9 9 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1769 EP 1773 DI 10.1116/1.577459 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300098 ER PT J AU BURNS, AR ORLANDO, TM JENNISON, DR STECHEL, EB AF BURNS, AR ORLANDO, TM JENNISON, DR STECHEL, EB TI STATE-RESOLVED STUDY OF COADSORPTION EFFECTS ON THE STIMULATED DISSOCIATION OF NO2 ON PT(111) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID NITROGEN-DIOXIDE; DESORPTION; SURFACE; OXYGEN; PHOTOCHEMISTRY; ADSORPTION; CO AB Stimulated surface processes, which are induced by electronic transitions, are especially sensitive to the presence of coadsorbates. We present here a detailed study of electron (5-350 eV) stimulated dissociation of chemisorbed NO2 on an O-covered Pt(111) surface, utilizing state-resolved laser resonance-ionization detection of the NO gas-phase product. Several dramatic effects on NO2 dissociation occur with increasing O atom coverage (up to theta-o = 0.75 monolayer). First there is a large (x 26) enhancement in the specific dissociation yield. Second, there is a narrowing of the translational energy distributions. A third observation is a distinct propensity (> 4:1 at low J) for populating the upper (OMEGA = 3/2) over the lower (OMEGA = 1/2) level of the spin-orbit-split No 2-PI-OMEGA ground state. The enhanced yield can be understood in terms of increased lifetime(s) due to an O-induced reduction in charge transfer screening. Diminished charge transfer also reduces the vibrational and rotational excitation of the NO product. The spin-orbit propensity might arise from substrate reneutralization of NO+ following Auger decay of the primary excitation. RP BURNS, AR (reprint author), SANDIA NATL LABS,DIV 1151,ALBUQUERQUE,NM 87185, USA. RI Stechel, Ellen/B-1253-2012 NR 17 TC 2 Z9 2 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1774 EP 1778 DI 10.1116/1.577460 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300099 ER PT J AU MALIK, IJ HRBEK, J AF MALIK, IJ HRBEK, J TI COADSORPTION-INDUCED EFFECTS AT SURFACES - THERMAL-DESORPTION SPECTROSCOPY AND X-RAY PHOTOELECTRON-SPECTROSCOPY STUDY OF OXYGEN COMPRESSION BY AU ON RU(001) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID HYDROGEN DESORPTION; MONOHYDRIDE PHASE; METAL; PHOTOEMISSION; ADSORPTION; SI(100); CO AB Coadsorption of gold on an oxygen saturated ruthenium surface causes dramatic changes in the energetics and kinetics of oxygen desorption and the selectivity of surface processes. The activation energy for desorption of oxygen (E(A)) is lowered, it is coverage independent, and the process is governed by first-order kinetics. The lower E(A) prevents oxygen bulk diffusion, which otherwise competes with desorption from a pure oxygen layer, thus leading to a twofold increase in the amount of desorbing oxygen. A complete analysis of desorption data yields E(A) = 81 +/- 4 kcal/mol, prefactor v(1) = (4 +/- 2) x 10(14) S-1, and reaction order n = 0.94. There is no direct interaction between Au and O, as inferred from gold desorption and x-ray photoelectron spectroscopy data. We propose that changes in E(A), v, and n arise as three-dimensional gold islands compress the oxygen overlayer causing a local increase in oxygen coverage. Desorption of oxygen occurs before the onset of Au desorption and as oxygen leaves the Ru surface, gold adatoms spread over Ru keeping the local oxygen coverage constant. RP MALIK, IJ (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. RI Hrbek, Jan/I-1020-2013 NR 21 TC 10 Z9 10 U1 3 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1806 EP 1809 DI 10.1116/1.577465 PN 2 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300104 ER PT J AU BLANCHARD, DL LESSOR, DL LAFEMINA, JP BAER, DR FORD, WK GUO, T AF BLANCHARD, DL LESSOR, DL LAFEMINA, JP BAER, DR FORD, WK GUO, T TI A LOW-ENERGY ELECTRON-DIFFRACTION STUDY OF THE MGO(001) SURFACE-STRUCTURE SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID HELIUM DIFFRACTION; MGO(100) SURFACE; RELAXATION; LEED; MGO; RHEED AB Low-energy electron diffraction (LEED) beam intensities were measured from the freshly cleaved [in ultrahigh vacuum] MgO(001) surface using beam energy modulation to avoid electrical charging. Dynamic LEED analysis of the data indicates: (1) an interlayer relaxation of (1 +/- 2)% and a rumple of the first layer ions of (5 +/- 2.5)%; (2) a new attenuation model containing no adjustable parameters gives fits to the data that are comparable to those using a constant imaginary optical potential (V(i); (3) a weak dependence of the optimum rumpling on the energy range of the data used. The structure determined in this study is compared to others reported in the literature for this surface, and the effects of lattice vibrations, attenuation length, and number of surface layers treated exactly are considered. C1 MONTANA STATE UNIV, CTR ADV MAT, BOZEMAN, MT 59717 USA. MONTANA STATE UNIV, DEPT PHYS, BOZEMAN, MT 59717 USA. RP BLANCHARD, DL (reprint author), PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. RI Baer, Donald/J-6191-2013 OI Baer, Donald/0000-0003-0875-5961 NR 26 TC 61 Z9 61 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1814 EP 1819 DI 10.1116/1.577467 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300106 ER PT J AU TAYLOR, TN MARTIN, JA AF TAYLOR, TN MARTIN, JA TI REACTION OF VAPOR-DEPOSITED ALUMINUM WITH COPPER OXIDES SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID XPS; CATALYSTS; SURFACES; OXYGEN; CUO AB Interfaces formed by controlled deposition of Al on Cu oxides at 300 K have been characterized using Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS). When Al is deposited onto a thin oxide grown on Cu(110) by atmospheric exposure, it completely scavenges the oxygen from the substrate material, increasing the O(1s) binding energy by 2.0 eV to give the value found for atmospheric oxidation of a thin Al film. Similar oxygen behavior is seen for Al deposition on sputter-deposited CuO with an enriched oxygen surface region, where multilayers of Al erase the shakeup satellites in the Cu(2p) region of the XPS spectrum to give features like those exhibited by Cu2O or metallic Cu. Having calibrated the fluence of the Al source with Rutherford backscattering spectrometry, the attenuation of the Cu 2p1/2 satellite after approximately one monolayer of Al deposition can be associated with oxygen reduction effects in the top 20 angstrom of the CuO. Approximately 7-8 equivalent monolayers of Al are converted to an oxide in the initial rapid reaction process. Further deposition leads to progressive development of the metallic Al signature in both the XPS and AES spectra. These measurements clearly demonstrate the dominant role played by Al, a strong oxide former, when it is placed in intimate contact with the distinctively weaker Cu oxide. RP TAYLOR, TN (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV CHEM & LASER SCI,LOS ALAMOS,NM 87545, USA. NR 14 TC 11 Z9 12 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1840 EP 1846 DI 10.1116/1.577473 PN 2 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300112 ER PT J AU LAFEMINA, JP DUKE, CB AF LAFEMINA, JP DUKE, CB TI DEPENDENCE OF OXIDE SURFACE-STRUCTURE ON SURFACE-TOPOLOGY AND LOCAL CHEMICAL BONDING SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID ELECTRONIC-ENERGY-STRUCTURE; V COMPOUND SEMICONDUCTORS; SILICON DIOXIDE; 110 SURFACES; BETA-CRISTOBALITE; MGO(001) SURFACE; CLEAVAGE FACES; ATOMIC STRUCTURES; LATTICE-DYNAMICS; MGO(100) SURFACE AB The atomic geometries of the charge neutral surfaces of several oxides exhibiting different crystal structures and varying participation of O(2p) electrons in the chemical bonding have been calculated using tight-binding total energy models. Surface structures have been computed for exemplary cubic (MgO), wurtzite (ZnO), beta-tridymite, and ideal beta-cristobalite (SiO2) oxides. The cubic oxide exhibits a minimum energy structure involving small outward relaxations of the oxygens and inward relaxations of the cations. For the cleavage faces of wurtzite ZnO, large bond-length-conserving relaxations occur because the surface atoms can relax without appreciable distortion of the local bond lengths. The charge neutral faces of beta-tridymite and ideal beta-cristobalite SiO2 also undergo bond-length-conserving relaxations. Thus the mechanism for the surface relaxation of tetrahedrally coordinated oxides is significantly different from that of the cubic oxides as is the role of the oxygen p electrons in the surface chemical bonding. Most importantly, the surface structural chemistry of charge neutral oxide surfaces reflects the interplay of both surface topology (via the ability to undergo bond-length-conserving relaxations) and local coordination chemistry (via the participation of p electrons in bonding versus nonbonding surface state bands). C1 XEROX CORP, WEBSTER RES CTR, WEBSTER, NY 14580 USA. RP LAFEMINA, JP (reprint author), PACIFIC NW LAB, MOLEC SCI RES CTR, POB 999, RICHLAND, WA 99352 USA. NR 63 TC 54 Z9 54 U1 1 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1847 EP 1855 DI 10.1116/1.577474 PN 2 PG 9 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300113 ER PT J AU ZEHNER, DM MOCHRIE, SGJ OCKO, BM GIBBS, D AF ZEHNER, DM MOCHRIE, SGJ OCKO, BM GIBBS, D TI STRUCTURE AND PHASES OF THE AU(001) SURFACE - X-RAY-SCATTERING MEASUREMENTS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID GRAPHITE; DIFFRACTION; TRANSITIONS; MONOLAYERS; AU(100); XENON AB X-ray diffraction is used to study the phase behavior and structure of the Au(001) surface between 300 K and the triple point. For T > 1170 K, the x-ray reflectivity is consistent with a thin, disordered surface film. At T = 1170 K, there is a reversible transition to an incommensurate, hexagonal overlayer that resides on top of the square substrate. At 970 K, the orientation of the hexagonal layer rotates discontinuously by 0.81-degrees with no observable change in incommensurability. C1 MIT,DEPT PHYS,CAMBRIDGE,MA 02139. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP ZEHNER, DM (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. NR 21 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1861 EP 1867 DI 10.1116/1.577476 PN 2 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300115 ER PT J AU LESSOR, DL DUKE, CB LIPPEL, PH BRANDES, GR CANTER, KF HORSKY, TN AF LESSOR, DL DUKE, CB LIPPEL, PH BRANDES, GR CANTER, KF HORSKY, TN TI LOW-ENERGY POSITRON DIFFRACTION ON CU(111) - IMPORTANCE OF SURFACE LOSS PROCESSES AT LARGE ANGLES OF INCIDENCE SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID ELECTRON-DIFFRACTION; CLEAVAGE FACES; CU(100); CDSE AB Intensities of positrons specularly diffracted from Cu(111) were measured at the Brandeis positron beam facility and analyzed in the energy range 8 eV < E < 134 eV for angles of incidence theta = 25, 30, 35, 40, 45, 50, 52, 57, and 60-degrees. These intensities were calculated for the known geometry of Cu(111) using a dynamical multiple scattering methodology. Above E = 50 eV this methodology gives a useful account of the measured intensities using a constant imaginary optical potential of V(i) = 4 eV. At lower energies strong energy dependences occur, associated both with multiple elastic scattering phenomena within atomic layers of Cu parallel to the surface and with the thresholds of inelastic channels (e.g., plasmon creation). Use of the free electron calculation of V(i) shows that energy dependence of inelastic processes is necessary to obtain a satisfactory description of the absolute magnitude of the diffracted intensities below E = 50 eV. Detailed comparison of the calculated and observed diffraction intensities reveals the necessity of incorporating surface loss processes explicitly into the model in order to achieve a quantitative description of the measured intensities for E < 40 eV and theta > 40-degrees. C1 XEROX CORP, WEBSTER RES CTR, WEBSTER, NY 14580 USA. BRANDEIS UNIV, DEPT PHYS, WALTHAM, MA 02254 USA. RP LESSOR, DL (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. RI Lippel, Philip/I-8170-2012 NR 30 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1874 EP 1878 DI 10.1116/1.577535 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300117 ER PT J AU ADE, H KIRZ, J HULBERT, S JOHNSON, E ANDERSON, E KERN, D AF ADE, H KIRZ, J HULBERT, S JOHNSON, E ANDERSON, E KERN, D TI IMAGES OF A MICROELECTRONIC DEVICE WITH THE X1-SPEM, A 1ST GENERATION SCANNING PHOTOEMISSION MICROSCOPE AT THE NATIONAL SYNCHROTRON LIGHT-SOURCE SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID PHOTOELECTRON MICROSCOPE; MICROPROBE; RADIATION AB We have recently completed the first generation scanning photoemission microscope at beamline X1A at the National Synchrotron Light Source (NSLS), the X1-SPEM. The instrument is designed to use the soft x-ray undulator at the NSLS as a high brightness source to illuminate a Fresnel zone plate, thus forming a finely focused probe, less-than-or-equal-to 0.4-mu-m in size, on the specimen surface. A grating monochromator selects the photon energy in the 400-800 eV range with an energy resolution of 0.8-2 eV. The flux in the zone plate focus is in the 10(8)-10(9) photons/s range. A single pass cylindrical mirror analyzer (CMA) is used to record photoemission spectra, or to form an image within a fixed electron energy bandwidth as the specimen is mechanically scanned. The best one-dimensional resolution achieved so far is 0.1-mu-m, as judged by the 25%-75% intensity rise across an edge. This is close to the diffraction limit of the zone plate used. Due to astigmatism introduced by the beamline optics, the two-dimensional resolution in the plane of least confusion is presently limited to 0.4-mu-m. Images of a microelectronic device are presented, along with some representative spectra, to demonstrate the present capabilities. With an upgrade of the beamline optics, and a new generation of zone plates, the two-dimensional spatial resolution in a second generation instrument is anticipated to be about 50 nm. C1 BROOKHAVEN NATL LAB,NSLS,UPTON,NY 11973. CTR XRAY OPT,LBL,BERKELEY,CA 94720. IBM CORP,THOMAS J WATSON RES CTR,YORKTOWN HTS,NY 10598. RP ADE, H (reprint author), SUNY STONY BROOK,DEPT PHYS,STONY BROOK,NY 11794, USA. RI Ade, Harald/E-7471-2011 NR 11 TC 18 Z9 18 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1902 EP 1906 DI 10.1116/1.577541 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300122 ER PT J AU BARTYNSKI, RA JENSEN, E GARRISON, K HULBERT, SL WEINERT, M AF BARTYNSKI, RA JENSEN, E GARRISON, K HULBERT, SL WEINERT, M TI SURFACE ELECTRONIC-STRUCTURE OF GAAS(110) STUDIED BY AUGER PHOTOELECTRON COINCIDENCE SPECTROSCOPY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID LINE-SHAPES; 110 SURFACE; SPECTRA; GAAS; PHOTOEMISSION; SI(111) AB Auger photoelectron coincidence spectroscopy has been used to study the M4,5 VV Auger spectra of GaAs(110). Using this technique, the Ga and As spectra can be separated and studied independently. The line shape of the As-M4,5 VV measured in coincidence with the As 3d photoemission line differs significantly from the conventional Auger spectrum. This is attributed to the surface electronic properties of the system. In addition, it is found that the ss component of the As spectrum is more intense than expected based on calculations using atomic matrix elements. The Ga-M4,5 VV spectrum, of which only the pp component is observed, agrees well with that expected from an independent electron model. A first principles electronic structure calculation of a five-layer GaAs(110) slab has been performed to aid in the interpretation of the Auger spectra. C1 BRANDEIS UNIV,DEPT PHYS,WALTHAM,MA 02254. RUTGERS STATE UNIV,SURFACE MODIFICAT LAB,PISCATAWAY,NJ 08855. BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP BARTYNSKI, RA (reprint author), RUTGERS STATE UNIV,DEPT PHYS & ASTRON,PISCATAWAY,NJ 08855, USA. NR 28 TC 10 Z9 10 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1907 EP 1912 DI 10.1116/1.577542 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300123 ER PT J AU BADER, SD LIU, C AF BADER, SD LIU, C TI ISSUES IN SURFACE MAGNETISM SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID CO/PT-LAYERED STRUCTURES; THIN-FILM MAGNETISM; NON-ISING BEHAVIOR; PHASE-TRANSITION; FERROMAGNETIC ORDER; FE FILMS; IRON FILMS; FCC IRON; HCP-FE; ANISOTROPY AB The field of surface magnetism is defined and a variety of contemporary issues are outlined and illustrated using examples predominantly from magneto-optic Kerr-effect studies. The issues involve the existence of magnetism in two dimensions (2D), trends in ordering temperatures with film thickness, the magnitude of the magnetic moments, the surface magnetic anisotropy, the 2D magnetic phase transition and critical behavior, and the existence of new and altered phases stabilized via epitaxy. RP BADER, SD (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Bader, Samuel/A-2995-2013 NR 73 TC 7 Z9 7 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 1924 EP 1928 DI 10.1116/1.577545 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300126 ER PT J AU CHOU, TS AF CHOU, TS TI PHOTON STIMULATED DESORPTION FROM ALUMINUM AND STAINLESS-STEEL SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID SURFACES AB Photon stimulated desorption of neutral species (PSD) is the major dynamic gas load in electron synchrotron light source. In the National Synchrotron Light Source, (NSLS) PSD presented initial machine commissioning difficulty. Sensitivity to surface contamination on PSD has been experienced during an incident of Fomblin Oil contamination 1. U10B-photon stimulated desorption experimental station is constructed to investigate: 1-the degree of the contribution to the photon stimulated desorption (PSD) from primary photon flux and scattered secondary photon flux, 2-the underlying mechanism for photon stimulated desorption, 3-criteria to chose the proper beam tube material for future accelerators such as SXLS, FEL, superconducting super collider (SSC), ALS.... In this report, only photon stimulated desorption of neutral species (PSD) from stainless steel and aluminum is reported. RP CHOU, TS (reprint author), BROOKHAVEN NATL LAB,NSLS BLDG 725C,UPTON,NY 11973, USA. NR 7 TC 1 Z9 1 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 2014 EP 2016 DI 10.1116/1.577446 PN 2 PG 3 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300144 ER PT J AU HALAMA, HJ GUO, YH AF HALAMA, HJ GUO, YH TI NONEVAPORABLE GETTER INVESTIGATION AT THE NATIONAL SYNCHROTRON LIGHT-SOURCE SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 37TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC CY OCT 08-12, 1990 CL TORONTO, CANADA SP AMER VACUUM SOC ID DESORPTION; SYSTEM AB We report H-2, CO, and CO2 pumping speed measurements on a linear pump using NEG strip St 707 (Saes Getters Inc.) as a function of both adsorbed gases and number of activations. To simulate the conditions of an operating storage ring a gas mixture of 50% H-2, 35% CO, and 15% CO2 is used in all measurements. Initial measured pumping speeds of > 450 lm-1 s-1 decrease to 200 and 100 lm-1 s-1 for H-2 and CO, respectively, after 70 air exposures. A further drop to 50 lm-1 s-1 for CO occurs at CO loading of 1 x 10(-2) Torr lm-1. CO2 and CO pumping speeds are about the same. The photon stimulated desorption for both baked and activated strips is an order of magnitude lower than that for stainless steel. RP HALAMA, HJ (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 7 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1991 VL 9 IS 3 BP 2070 EP 2073 DI 10.1116/1.577415 PN 2 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA FR763 UT WOS:A1991FR76300156 ER PT J AU KAZMERSKI, LL AF KAZMERSKI, LL TI SPECIFIC ATOM IMAGING, NANOPROCESSING, AND ELECTRICAL NANOANALYSIS WITH SCANNING TUNNELING MICROSCOPY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID SI(111)2X1 SURFACE; OPTICAL MICROSCOPY; CUINSE2 SURFACES; THIN-FILMS; SPECTROSCOPY; SILICON; LITHOGRAPHY; OXYGEN; FIELD AB Scanning tunneling microscopy is used to provide integrated imaging, processing and electrical characterization on the nanoscale level for the same defect region in CuInSe2. The use of coordinated electronic and photon biasing is demonstrated to provide specific atomic imaging for covalently bonded semiconductors. The high-resolution conditions of the instrument provide for nanoprocessing with passivation of defects using oxygen. The same regions are analyzed for minority-carrier losses by a nanoscale electron-beam induced current technique. RP KAZMERSKI, LL (reprint author), SOLAR ENERGY RES INST,GOLDEN,CO 80401, USA. NR 37 TC 35 Z9 35 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1991 VL 9 IS 3 BP 1549 EP 1556 DI 10.1116/1.585421 PG 8 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA FR866 UT WOS:A1991FR86600021 ER PT J AU DIMARZIO, D LEE, MB DECARLO, J GIBAUD, A HEALD, SM AF DIMARZIO, D LEE, MB DECARLO, J GIBAUD, A HEALD, SM TI STUDY OF TEMPERATURE-DEPENDENT STRUCTURAL-CHANGES IN MOLECULAR-BEAM EPITAXY GROWN HG1-XCDXTE BY X-RAY LATTICE-PARAMETER MEASUREMENTS AND EXTENDED X-RAY ABSORPTION FINE-STRUCTURE SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 1990 US WORKSHOP ON THE PHYSICS AND CHEMISTRY OF MERCURY CADMIUM TELLURIDE AND NOVEL INFRARED DETECTOR MATERIALS CY OCT 02-04, 1990 CL SAN FRANCISCO, CA SP COMMUNICAT ELECTRON COMMAND CTR NIGHT VIS & ELECTRO OPT, USN, OFF NAVAL TECHNOL, ASAF, OFF SCI RES, AMER VACUUM SOC ID THERMAL-EXPANSION; CDTE; RELAXATION; STRESSES; ALLOYS; LAYERS; FILMS; GAAS AB Infrared detectors fabricated from Hg1-xCd(x)Te typically operate in the 60 to 160 K range. The temperature dependence of the atomic structure of HgCdTe may influence device performance. We present the first detailed study of the x-ray diffraction lattice parameters of molecular-beam epitaxy grown Hg1-xCd(x)Te epilayers between 15 and 300 K. The epilayers were grown on (100) oriented CdTe substrates, and varied in thickness (6 to 11-mu-m) and composition (x = 0-0.172). The (400) reflection was measured to determine the lattice parameter a perpendicular-to normal to the film. HgTe (x = 0) exhibited normal lattice contraction (alpha = 4.7 x 10(-6) +/- 0.3 K-1 at 300 K), with a minimum in a perpendicular-to at 60 K, and an expansion of a perpendicular-to below 60 K. In addition to showing a minimum in a perpendicular-to at 60 K, some of the Hg1-xCd(x)Te (x not-equal 0) epilayers (10-mu-m thick) exhibited anomalous behaviour with varying degrees of thermal hysteresis in a perpendicular-to. The average contraction of a perpendicular-to for these epilayers from 300 to 60 K is 0.006 angstrom. This is compared with results we have obtained from a temperature dependent extended x-ray absorption fine structure study of these HgCdTe epilayers: whereas HgTe exhibited a normal thermal contraction of the Hg-Te bond length consistent with the lattice parameter results, in the HgCdTe epilayers this bond contracts 0.02 to 0.03 angstrom on cooling from 300 to 10 K. We also present lattice parameter measurements for a thin cap layer of CdTe on HgCdTe. An increase of 0.0134 angstrom in a perpendicular-to relative to the bulk was observed for a 1000 angstrom layer of CdTe on HgCdTe at 300 K. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RP DIMARZIO, D (reprint author), GRUMMAN CORP,RES CTR,BETHPAGE,NY 11714, USA. NR 22 TC 2 Z9 2 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1991 VL 9 IS 3 BP 1886 EP 1891 DI 10.1116/1.585376 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA FR866 UT WOS:A1991FR86600080 ER PT J AU ONEILL, RV TURNER, SJ CULLINAN, VI COFFIN, DP COOK, T CONLEY, W BRUNT, J THOMAS, JM CONLEY, MR GOSZ, J AF ONEILL, RV TURNER, SJ CULLINAN, VI COFFIN, DP COOK, T CONLEY, W BRUNT, J THOMAS, JM CONLEY, MR GOSZ, J TI MULTIPLE LANDSCAPE SCALES - AN INTERSITE COMPARISON SO LANDSCAPE ECOLOGY LA English DT Article DE HIERARCHY; SCALE; VEGETATION AB Vegetation transect data from three locations were analyzed to determine if multiple scales of pattern could be detected. The sites included a semiarid grassland in New Mexico, a series of calcareous openings in a deciduous forest in Tennessee, and a shrub-steppe system in Washington. The data were explored with four statistical techniques. A scale of pattern was accepted if detected by more than one analytical method or located by a single method in multiple taxa. The analyses indicated 3-5 scales of pattern on all three sites, as predicted by Hierarchy Theory. C1 DIV WILDLIFE & ECOL, LYNEHAM, ACT 2602, Australia. PACIFIC NW LABS, MARINE RES LAB, SEQUIM, WA 98382 USA. COLORADO STATE UNIV, DEPT RANGE SCI, FT COLLINS, CO 80523 USA. UNIV VIRGINIA, DEPT ENVIRONM SCI, CHARLOTTESVILLE, VA 22903 USA. US DOE, OFF HLTH & ENVIRONM RES, DIV ECOL RES ER75, WASHINGTON, DC 20545 USA. UNIV NEW MEXICO, DEPT BIOL, ALBUQUERQUE, NM 87131 USA. BATTELLE MEM INST, PACIFIC NW LABS, DEPT ENVIRONM SCI, RICHLAND, WA 99352 USA. NEW MEXICO STATE UNIV, DEPT MATH SCI, LAS CRUCES, NM 88003 USA. RP ONEILL, RV (reprint author), OAK RIDGE NATL LAB, DIV ENVIRONM SCI, OAK RIDGE, TN 37831 USA. RI Brunt, James/G-9843-2011 OI Brunt, James/0000-0001-9174-4408 NR 0 TC 61 Z9 64 U1 3 U2 6 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0921-2973 J9 LANDSCAPE ECOL JI Landsc. Ecol. PD MAY PY 1991 VL 5 IS 3 BP 137 EP 144 DI 10.1007/BF00158061 PG 8 WC Ecology; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA FT835 UT WOS:A1991FT83500002 ER PT J AU KAUSHIK, VS DATYE, AK TSAO, SS GUILINGER, TR KELLY, MJ AF KAUSHIK, VS DATYE, AK TSAO, SS GUILINGER, TR KELLY, MJ TI MICROSTRUCTURE OF PORES IN N+ SILICON SO MATERIALS LETTERS LA English DT Article ID POROUS SILICON; FORMATION MECHANISM; LAYERS AB The structure of pores in n-/n+/n- silicon structures has been studied by cross-section transmission electron microscopy. Under the experimental conditions examined, the pore directions in the n+ layer follow the current path and do not show crystallographic preference. Stray pores were observed in the n- layer and they appear to grow along <100> directions. By using cross sections transverse to the pore length, we have obtained end-on views that show that the pore walls tend to facet along {111} planes. We have also observed wafer surface faceting on {113} planes as a result of the anodization process. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP DATYE, AK (reprint author), UNIV NEW MEXICO,DEPT CHEM & NUCL ENGN,ALBUQUERQUE,NM 87131, USA. OI Datye, Abhaya/0000-0002-7126-8659 NR 11 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-577X J9 MATER LETT JI Mater. Lett. PD MAY PY 1991 VL 11 IS 3-4 BP 109 EP 114 DI 10.1016/0167-577X(91)90096-O PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA FQ019 UT WOS:A1991FQ01900010 ER PT J AU HAYNES, HD AF HAYNES, HD TI CHECK VALVES - OAK-RIDGES NEW DIAGNOSTICS SO MECHANICAL ENGINEERING LA English DT Article RP HAYNES, HD (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0025-6501 J9 MECH ENG JI Mech. Eng. PD MAY PY 1991 VL 113 IS 5 BP 64 EP 69 PG 6 WC Engineering, Mechanical SC Engineering GA FK707 UT WOS:A1991FK70700013 ER PT J AU PETTI, PL LYMAN, JT CASTRO, JR AF PETTI, PL LYMAN, JT CASTRO, JR TI SENSITIVITY OF HELIUM BEAM-MODULATOR DESIGN TO UNCERTAINTIES IN BIOLOGICAL DATA SO MEDICAL PHYSICS LA English DT Article DE CHARGED-PARTICLE THERAPY; BEAM-MODULATING DEVICE; BIOLOGICAL MODELING ID CALIFORNIA-ONCOLOGY-GROUP; HEAVY-IONS; CELLS; RADIOBIOLOGY; THERAPY; TRIAL AB The goal in designing beam-modulating devices for heavy charged-particle therapy is to achieve uniform biological effects across the spread-peak region of the beam. To accomplish this, the linear-quadratic model for cell survival has been used to describe the biological response of the target cells to charged-particle radiation. In this paper, the sensitivity of the beam-modulator design in the high-dose region to the values of the linear-quadratic variables alpha and beta has been investigated for a 215-MeV/u helium beam, and implications for higher LET beams are discussed. The major conclusions of this work are that, for helium over the LET range of 2 to 16 keV/mu, uncertainties in measuring alpha and beta for a given cell type which are of the order 20% or less have a negligible effect on the beam-modulator design (i.e., on the slope of the spread Bragg peak); uncertainties less than or equal to 10% in the dose-averaged LET at each depth are unimportant; and, if the linear-quadratic variables for the tumor differ from those used in the beam-modulator design by a constant factor between about 0.5 and 3, then the resultant nonuniformity in the photon-equivalent dose delivered to the tumor is within +/- 2.5%. It is also shown that for any ion, if the nominal values of alpha or beta used by the beam-modulator design program differ from their actual values by a constant factor, then the maximum errors possible in the beam-modulator design may be characterized by two limiting depth-dose curves such that the ratio of the dose at the proximal end of the spread Bragg curve to the dose at the distal end of the spread peak is given by alpha-distal/alpha-prox for the steepest curve, and square-root beta-distal/beta-prox for the flattest curve. RP PETTI, PL (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV RES MED & RADIAT BIOPHYS,BERKELEY,CA 94720, USA. FU NCI NIH HHS [CA 19138, CA 21744] NR 25 TC 9 Z9 9 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0094-2405 J9 MED PHYS JI Med. Phys. PD MAY-JUN PY 1991 VL 18 IS 3 BP 506 EP 512 DI 10.1118/1.596654 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA FR130 UT WOS:A1991FR13000024 PM 1908045 ER PT J AU PETTI, PL LYMAN, JT RENNER, TR CASTRO, JR COLLIER, JM DAFTARI, IK LUDEWIGT, BA AF PETTI, PL LYMAN, JT RENNER, TR CASTRO, JR COLLIER, JM DAFTARI, IK LUDEWIGT, BA TI DESIGN OF BEAM-MODULATING DEVICES FOR CHARGED-PARTICLE THERAPY SO MEDICAL PHYSICS LA English DT Article DE CHARGED-PARTICLE THERAPY; BEAM-MODULATING DEVICE ID HEAVY-IONS; RADIATION; CELLS AB The computer modeling program used to design beam-modulating devices for charged-particle therapy at Lawrence Berkeley Laboratory has been improved to allow a more realistic description of the beam. The original program used a single calculated Bragg peak to design the spread Bragg peak. The range of this curve was shifted so that Bragg curves of varying ranges could be superimposed. The new version of the program allows several measured Bragg curves with different ranges to be used as input, and interpolates between them to obtain the required data for the superposition calculation. The experimental configuration for measuring these input curves simulated therapy conditions. Seven beam-modulating propellers with spread Bragg-peak widths ranging from 2.2 to 14.4 cm were designed and constructed for a 215-MeV/u helium beam using this new design program. Depth-dose distributions produced by these new propellers were in good agreement with predicted distributions, and these propellers are currently being used clinically. RP PETTI, PL (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV RES MED & RADIAT BIOPHYS,BERKELEY,CA 94720, USA. FU NCI NIH HHS [CA 19138, CA 21744] NR 25 TC 20 Z9 21 U1 3 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0094-2405 J9 MED PHYS JI Med. Phys. PD MAY-JUN PY 1991 VL 18 IS 3 BP 513 EP 518 DI 10.1118/1.596655 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA FR130 UT WOS:A1991FR13000025 PM 1908046 ER PT J AU STINCHCOMB, TG DURHAM, JS FISHER, DR AF STINCHCOMB, TG DURHAM, JS FISHER, DR TI OBTAINING S-VALUES FOR RECTANGULAR SOLID TUMORS INSIDE RECTANGULAR SOLID HOST ORGANS SO MEDICAL PHYSICS LA English DT Article DE INTERNAL DOSIMETRY; TUMOR; S-VALUES; SPECIFIC ABSORBED FRACTIONS AB A method is described for obtaining S values between a tumor and its host organ for use with the MIRD formalism. It applies the point-source specific absorbed fractions for an infinite water medium, tabulated by Berger, to a rectangular solid of arbitrary dimensions which contains a rectangular tumor of arbitrary dimensions. Contributions from pairs of source and target volume elements are summed for the S values between the tumor and itself, between the remaining healthy host organ and itself, and between the tumor and the remaining healthy host organ, with the reciprocity theorem assumed for the last. This method labeled MTUMOR, is interfaced with the widely used MIRDOSE program which incorporates the MIRD formalism. An example is calculated. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. RP STINCHCOMB, TG (reprint author), DE PAUL UNIV, DEPT PHYS, CHICAGO, IL 60614 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0094-2405 J9 MED PHYS JI Med. Phys. PD MAY-JUN PY 1991 VL 18 IS 3 BP 555 EP 558 DI 10.1118/1.596732 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA FR130 UT WOS:A1991FR13000032 PM 1870500 ER PT J AU JONES, WB HILLS, CR POLONIS, DH AF JONES, WB HILLS, CR POLONIS, DH TI MICROSTRUCTURAL EVOLUTION OF MODIFIED 9CR-1MO STEEL SO METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article AB The tempering and subsequent annealing of modified 9Cr-1Mo steel have been investigated to determine the influence of trace amounts of V and Nb on the sequence of precipitation processes and to identify the basis for the enhanced high-temperature strength compared to the standard 9Cr-1Mo composition. Air cooling (normalizing) from 1045-degrees-C results in the precipitation of fine (Fe,Cr)C-3 particles within the martensite laths. Additional carbide precipitation and changes in the dislocation structure occur during the tempering of martensite at 700-degrees-C and 760-degrees-C after normalizing. The precipitation of M23C6 carbides occurs preferentially at lath interfaces and dislocations. The formation of Cr2C was detected during the first hour of tempering over the range of 650-degrees-C to 760-degrees-C but was replaced by V4C3 within 1 hour at 760-degrees-C. During prolonged annealing at 550-degrees-C to 650-degrees-C, following tempering, the lath morphology remains relatively stable; partitioning of the laths into subgrains and some carbide coarsening are evident after 400 hours of annealing at 650-degrees-C, but the lath morphology persists. The enhanced martensite lath stability is attributed primarily to the V4C3 precipitates distributed along the lath interfaces and is suggested as the basis for the improved performance of the modified 9Cr-1Mo alloy under elevated temperature tensile and creep conditions. RP JONES, WB (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87085, USA. NR 19 TC 116 Z9 117 U1 2 U2 14 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0360-2133 J9 METALL TRANS A PD MAY PY 1991 VL 22 IS 5 BP 1049 EP 1058 DI 10.1007/BF02661098 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA FK357 UT WOS:A1991FK35700009 ER PT J AU ENGLER, DA HAUSER, MR COOK, JS NIYOGI, SK AF ENGLER, DA HAUSER, MR COOK, JS NIYOGI, SK TI AROMATICITY AT POSITION-37 IN HUMAN EPIDERMAL GROWTH-FACTOR IS NOT OBLIGATORY FOR ACTIVITY SO MOLECULAR AND CELLULAR BIOLOGY LA English DT Article ID NUCLEAR MAGNETIC-RESONANCE; SITE-DIRECTED MUTAGENESIS; FACTOR-ALPHA; RECEPTOR-BINDING; CELLS; FRAGMENTS; PURIFICATION; CHAIN; VIRUS; FIBROBLAST AB The third disulfide loop (amino acids 33 to 42) of human epidermal growth factor (hEGF) encompasses the region of highest amino acid conservation among all of the EGF-like family of molecules. The importance of some of these highly conserved residues for the maintenance of biological activity, especially the aromatic amino acid tyrosine at position 37, has until now been considered essential on the basis of previous studies with the EGF-like molecule transforming growth factor alpha. Variants at the Tyr-37 position of hEGF were constructed by site-directed mutagenesis. The substituting amino acids were phenylalanine, histidine, serine, alanine, aspartic acid, arginine, and glycine. The variants were tested for their ability to competitively displace native [I-125]hEGF from its receptor and to stimulate the protein-tyrosine kinase activity of the receptor; the order of efficacy of substituting amino acids was Phe > His > Ser > Ala > Asp > Arg > Gly in both assays. All were effective, with no or only moderate reduction in potency, in stimulating the incorporation of [H-3]thymidine into acid-insoluble material of quiescent mouse A31 cells. Only Tyr-37 --> Ala, Tyr-37 --> Arg and Tyr-37 --> Gly were slightly less potent in the cell assay. Thus, neither tyrosine nor another aromatic amino acid at position 37 in hEGF is essential for full biolgoical activity. C1 UNIV TENNESSEE,OAK RIDGE GRAD SCH BIOMED SCI,POB 2009,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,DIV BIOL,PROT ENGN & MOLEC MUTAGENESIS PROGRAM,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,MEMBRANE BIOL PROGRAM,OAK RIDGE,TN 37831. FU NCI NIH HHS [CA 50735, T32 CA 09336, T32 CA 09104] NR 46 TC 16 Z9 16 U1 0 U2 0 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0270-7306 J9 MOL CELL BIOL JI Mol. Cell. Biol. PD MAY PY 1991 VL 11 IS 5 BP 2425 EP 2431 PG 7 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA FJ155 UT WOS:A1991FJ15500010 PM 1850095 ER PT J AU MURRY, MA WOLK, CP AF MURRY, MA WOLK, CP TI IDENTIFICATION AND INITIAL UTILIZATION OF A PORTION OF THE SMALLER PLASMID OF ANABAENA-VARIABILIS ATCC-29413 CAPABLE OF REPLICATION IN ANABAENA SP STRAIN M-131 SO MOLECULAR & GENERAL GENETICS LA English DT Article DE CYANOBACTERIA; ANABAENA-VARIABILIS; PLASMIDS; SHUTTLE VECTORS; CONJUGATION ID LARGE ENDOGENOUS PLASMID; FILAMENTOUS CYANOBACTERIA; ANACYSTIS-NIDULANS; ESCHERICHIA-COLI; STRUCTURAL GENES; CLONING VECTOR; CONSTRUCTION; DNA; TRANSFORMATION; NOSTOC AB Anabaena variabilis ATCC 29413 contains two cryptic plasmids. Clones of the smaller (41 kb) plasmid, designated pRDS1, is cosmid vectors were used to construct a physical map. A clone bank of pRDS1 constructed by ligating fragments from a XhoII digest of a pRDS1 cosmid clone into a mobilizable plamid was used to locate an origin of replication of pRDS1. Because we were unable to cure A. variabilis of pRDS1, the clone bank was transferred by conjugation to another strain of Anabaena sp., strain M-131. A 5.3 kb fragment of pRDS1 contained all of the sequences necessary for replication in Anabaena sp. strain M-131 as judged by the ability to rescue the hybrid vector from exconjugants in unchanged form after many generations. Hybrid plasmids derived from pRDS1, one bearing genes for luciferase, were also transferred by conjugation to A. variabilis, where they appeared to recombine with pRDS1. C1 MICHIGAN STATE UNIV,US DOE,PLANT RES LAB,E LANSING,MI 48824. MICHIGAN STATE UNIV,DEPT BOT & PLANT PATHOL,E LANSING,MI 48824. NR 35 TC 4 Z9 4 U1 1 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0026-8925 J9 MOL GEN GENET JI Mol. Gen. Genet. PD MAY PY 1991 VL 227 IS 1 BP 113 EP 119 DI 10.1007/BF00260715 PG 7 WC Biochemistry & Molecular Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Genetics & Heredity GA FN655 UT WOS:A1991FN65500018 PM 1904532 ER PT J AU GRILL, E SOMERVILLE, C AF GRILL, E SOMERVILLE, C TI CONSTRUCTION AND CHARACTERIZATION OF A YEAST ARTIFICIAL CHROMOSOME LIBRARY OF ARABIDOPSIS WHICH IS SUITABLE FOR CHROMOSOME WALKING SO MOLECULAR & GENERAL GENETICS LA English DT Article DE YEAST ARTIFICIAL CHROMOSOME LIBRARY; POLYMERASE CHAIN REACTION; RESTRICTION FRAGMENT LENGTH POLYMORPHISM; CHROMOSOME WALKING ID POLYMORPHISM LINKAGE MAP; LARGE SEGMENTS; THALIANA; GENOME; DNA; CLONES; CLONING; VECTORS AB A yeast artificial chromosome (YAC) genomic library of Arabidopsis thaliana was constructed in a derivative of the vector pYAC4 which was modified to facilitate the production of end-specific probes for chromosome walking. Experiments in which a subset of 2300 clones from the library were probed with 30 restriction fragment length polymorphism (RFLP) markers indicated that, on the average, the entire genome is represented once in each 800 YAC clones. Thus, the complete library of more than 20 000 YACs is expected to contain most or all of the Arabidopsis genome with a high probability. The YAC clones examined in the sample had an average insert size of approximately 150 kb +/- 10 and represented more than 5% of the Arabidopsis genome. Based on the properties of the library and the currently available RFLP maps for Arabidopsis, only one or two steps from flanking RFLPs should be sufficient to isolate an average gene in Arabidopsis by chromosome walking with the YACs. In order to facilitate chromosome walking, a method for the production of hybridization probes from the ends of the inserts was employed that is based on a combination of pre-amplification of the vector/insert junction sequences via the polymerase chain reaction and specific transcription from T3 or T7 RNA polymerase promoters flanking the cloning site in the YAC vector. C1 MICHIGAN STATE UNIV,US DOE,PLANT RES LAB,E LANSING,MI 48824. RI Somerville, Christopher/A-4048-2009 OI Somerville, Christopher/0000-0003-4647-0094 NR 23 TC 139 Z9 139 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0026-8925 J9 MOL GEN GENET JI Mol. Gen. Genet. PD MAY PY 1991 VL 226 IS 3 BP 484 EP 490 PG 7 WC Biochemistry & Molecular Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Genetics & Heredity GA FN094 UT WOS:A1991FN09400018 PM 1674816 ER PT J AU SPENCER, RE SCHILIZZI, RT FANTI, C FANTI, R PARMA, P VANBREUGEL, WJM VENTURI, T MUXLOW, TWB RENDONG, N AF SPENCER, RE SCHILIZZI, RT FANTI, C FANTI, R PARMA, P VANBREUGEL, WJM VENTURI, T MUXLOW, TWB RENDONG, N TI HIGH-RESOLUTION OBSERVATIONS OF 8 3CR COMPACT STEEP-SPECTRUM RADIO-SOURCES SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article ID VLBI OBSERVATIONS; MAPS; 3C-286; GHZ; 3C-119 AB We present high-resolution observations carried out at 18-cm wavelength with MERLIN and the European VLBI Network (EVN) on eight compact steep-spectrum (CSS) sources from the 3CR catalogue (3C43, 186, 190, 286, 299, 318, 346, 454). The typical resolution achieved on maps made with combined data is less-than-or-similar to that in large-scale powerful radio sources, but several jets show pronounced curvature and bending perhaps indictive of strong interactions with an interstellar medium. The jet/counter-jet brightness ratios are consistent with moderate (beta greater-than-or-similar-to 0.7) Doppler boosting. C1 NETHERLANDS FDN RES ASTRON,7990 AA DWINGELOO,NETHERLANDS. DIPARTIMENTO ASTRON,I-40126 BOLOGNA,ITALY. CNR,IST RADIOASTRON,I-40126 BOLOGNA,ITALY. UNIV CALIF LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550. CHINESE ACAD SCI,BEIJING OBSERV,BEIJING,PEOPLES R CHINA. RP SPENCER, RE (reprint author), UNIV MANCHESTER,NUFFIELD RADIO ASTRON LABS,JODRELL BANK,MACCLESFIELD SK11 9DL,CHESHIRE,ENGLAND. OI Muxlow, Thomas/0000-0001-5797-8796 NR 34 TC 84 Z9 85 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 1 PY 1991 VL 250 IS 1 BP 225 EP 240 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FJ872 UT WOS:A1991FJ87200025 ER PT J AU BRODSKY, MB AF BRODSKY, MB TI SINGLE-CRYSTALS - WHAT THEY TELL ABOUT HIGH-TEMPERATURE SUPERCONDUCTIVITY SO MRS BULLETIN LA English DT Article RP BRODSKY, MB (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0883-7694 J9 MRS BULL JI MRS Bull. PD MAY PY 1991 VL 16 IS 5 BP 31 EP 35 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA FL295 UT WOS:A1991FL29500003 ER PT J AU SHADLEY, JD WHITLOCK, JL ROTMENSCH, J ATCHER, RW TANG, J SCHWARTZ, JL AF SHADLEY, JD WHITLOCK, JL ROTMENSCH, J ATCHER, RW TANG, J SCHWARTZ, JL TI THE EFFECTS OF RADON DAUGHTER ALPHA-PARTICLE IRRADIATION IN K1 AND XRS-5 CHO CELL-LINES SO MUTATION RESEARCH LA English DT Article DE RADON; RADIATION MUTAGENESIS; DNA REPAIR MUTANTS; ALPHA-RADIATION ID SENSITIVE MUTANT-CELLS; DOUBLE-STRAND BREAKS; SISTER-CHROMATID EXCHANGES; DNA-DAMAGING AGENTS; HAMSTER OVARY CELLS; CHROMOSOMAL-ABERRATIONS; MAMMALIAN-CELLS; CYTOGENETICAL CHARACTERIZATION; RESTRICTION ENDONUCLEASES; LET RADIATIONS AB We investigated the radiobiological effects of the radon daughter bismuth-212 (Bi-212) in Chinese hamster ovary (CHO) K1 cells and in xrs-5 cells, which are X-ray sensitive and deficient in the ability to rejoin DNA double-strand breaks. The cells were exposed to 250 kVp X-rays or to Bi-212 chelated to diethylene triamine pentaacetic acid (DTPA); chelation of Bi-212 to DTPA prevented its attachment to or entry into the cells. Cytotoxic, clastogenic, and mutagenic responses of the cells were measured and RBEs (D10, 2 chromatid aberrations/cell and 10 induced 6-thioguanine-resistant mutants) were calculated to be 3.8, 3.5, and 3.9, respectively for K1, and 1.4, 0.8, and 5.1, respectively, for xrs-5. With the exception of the RBE of less than 1 for alpha-induced aberrations in xrs-5, the results are consistent with the following conclusions: (1) alpha-particles are in general more effective cytotoxic, clastogenic and mutagenic agents than X-rays; (2) the primary lethal and clastogenic lesion induced by both X-rays and alpha-particles is probably a DNA double-strand break; (3) DNA double-strand breaks induced by alpha-radiation are less well repaired than those induced by X-rays, although a portion of alpha-induced damage is repairable; and (4) deficiencies in rejoining DNA double-strand breaks affect the clastogenic and cytotoxic effects of X-rays and alpha-radiation, not their mutagenic effects. The RBE of 0.8 for aberration induction in xrs-5 cells could reflect a deficiency in the ability of these cells to convert alpha-induced damage to chromosome aberrations. Alternatively, the RBE of less than 1 might reflect an unusual sensitivity of xrs-5 cells to alpha-induced G2 delays. C1 ARGONNE NATL LAB, DIV BIOL & MED RES, 9700 S CASS AVE, ARGONNE, IL 60439 USA. ARGONNE NATL LAB, DIV CHEM, ARGONNE, IL 60439 USA. UNIV CHICAGO, DEPT RADIAT & CELLULAR ONCOL, CHICAGO, IL 60637 USA. UNIV CHICAGO, DEPT OBSTET & GYNECOL, CHICAGO, IL 60637 USA. OI Atcher, Robert/0000-0003-4656-2247 NR 45 TC 32 Z9 32 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8262 J9 MUTAT RES JI Mutat. Res. PD MAY PY 1991 VL 248 IS 1 BP 73 EP 83 DI 10.1016/0027-5107(91)90089-7 PG 11 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA FK834 UT WOS:A1991FK83400008 PM 2030713 ER PT J AU STRAUME, T KWAN, TC GOLDSTEIN, LS DOBSON, RL AF STRAUME, T KWAN, TC GOLDSTEIN, LS DOBSON, RL TI MEASUREMENT OF NEUTRON-INDUCED GENETIC-DAMAGE IN MOUSE IMMATURE OOCYTES SO MUTATION RESEARCH LA English DT Article DE CHROMOSOME ABERRATIONS; DOMINANT LETHAL MUTATIONS; NEUTRON IRRADIATION; OOCYES, IMMATURE (MOUSE) ID FEMALE MICE; RADIATION; SENSITIVITY; MUTATIONS; INVITRO; TARGET AB Recent experimental evidence concerning the nature of radiosensitive targets in mouse immature (resting) oocytes has led to new experimental designs that permit measurement of radiation-induced genetic damage in these important cells. We have previously reported initial results of the detection of genetic damage in mouse immature oocytes using monoenergetic 0.43-MeV neutrons. Here we provide a full report of our data and compare the genetic sensitivity of immature oocytes with those measured by others for maturing oocytes. Until recently, all attempts to detect radiation-induced genetic damage in mouse immature oocytes had failed. This appears to have been because the radiation types and modes of dose delivery used in those studies did not sufficiently spare the hypersensitive lethality target (the plasma membrane) while at the same time deposit enough dose in DNA to produce detectable mutations. Recoil protons from 0.43-MeV neutrons produce short ionization tracks (2.6-mu-m, mean) and can therefore deposit energy in the DNA without simultaneously traversing the plasma membrane. Using these particles, we have obtained dose-response relationships for both chromosome aberrations and dominant lethal mutations in oocytes from females irradiated 8-12 weeks earlier, when oocytes were immature. Results suggest that the intrinsic mutational sensitivity of mouse immature oocytes is not very different from that of maturing oocytes. C1 UNIV CALIF SAN FRANCISCO,SAN FRANCISCO,CA 94143. RP STRAUME, T (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,POB 5507,LIVERMORE,CA 94550, USA. NR 34 TC 17 Z9 17 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8262 J9 MUTAT RES PD MAY PY 1991 VL 248 IS 1 BP 123 EP 133 DI 10.1016/0027-5107(91)90094-5 PG 11 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA FK834 UT WOS:A1991FK83400013 PM 2030702 ER PT J AU RUSSELL, LB BANGHAM, JW AF RUSSELL, LB BANGHAM, JW TI THE PATERNAL GENOME IN MOUSE ZYGOTES IS LESS SENSITIVE TO ENU MUTAGENESIS THAN THE MATERNAL GENOME SO MUTATION RESEARCH LA English DT Article DE ZYGOTES, MOUSE; PATERNAL GENOME; N-ETHYL-N-NITROSOUREA, INDUCTION OF POINT MUTATIONS; ENU MUTAGENESIS ID LOCUS MUTATIONS; FEMALE MICE; ETHYLNITROSOUREA; FREQUENCY; EXPOSURE; DEATH; EGGS AB The two parental genomes lie separate within the zygote and may be differentially affected by environmental influences. We have shown earlier (Russell et al., 1988) that the maternal genome within the mouse zygote is exquisitely sensitive to the induction of point mutations by N-ethyl-N-nitrosourea (ENU), and that the initial lesion probably occurs in one strand of the DNA. The present experiment measured specific-locus mutation induction in the paternal genome. Zygotes containing a multiple-recessive maternal genome (a; b; p c(ch); d se; s) and the corresponding wild-type alleles in the paternal one were exposed to 50 mg ENU/kg in vivo at one of two stages: the presumed times of sperm entry and early pronuclear stage. At weaning age, the resulting mice were examined for mutations at the marked loci as well as for other mutations producing externally visible phenotypes. At the marked loci, one possible mosaic (for b) was observed among 2113 classified offspring that had been treated with ENU as zygotes; this animal failed to transmit a mutation. By contrast, in the reciprocal cross (which tests the maternal genome) we had observed 8 specific-locus mutations (6 of them mosaics) among 1555 offspring that had received the same dose of ENU during sperm entry (and completion of oocyte meiosis II). In present experiment, we also found one mutation at other loci (two at other loci in the reciprocal cross). The frequency of offspring with small white belly spots was significantly greater in the treated groups (3.5 and 1.9% at the earlier and later stage, respectively) than in the control (1.0%), the excess being almost entirely due to daughters. Genetic tests of a large number of such offspring failed to find a genetic cause. Instead, it appears that this phenotype may be influenced by factors in the intrauterine environment. It is concluded that shortly after sperm entry, the paternal genome of the zygote is less sensitive than the maternal one to the induction of mutations by ENU. RP RUSSELL, LB (reprint author), OAK RIDGE NATL LAB,DIV BIOL,POB 2009,OAK RIDGE,TN 37831, USA. FU NIEHS NIH HHS [222Y01-ES-10067] NR 16 TC 18 Z9 18 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8262 J9 MUTAT RES PD MAY PY 1991 VL 248 IS 1 BP 203 EP 209 DI 10.1016/0027-5107(91)90102-T PG 7 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA FK834 UT WOS:A1991FK83400021 PM 2030709 ER PT J AU JEN, E AF JEN, E TI EXACT SOLVABILITY AND QUASI-PERIODICITY OF ONE-DIMENSIONAL CELLULAR AUTOMATA SO NONLINEARITY LA English DT Article AB Cellular automata are a class of mathematical systems characterized by discreteness (in space, time, and state values), determinism, and local interaction. Little is known mathematically about automata with nonlinear interaction rules. This paper establishes that certain nonlinear automata on finite lattices may be mapped exactly onto a linear automaton, thus providing an 'exact solution' for the nonlinear systems, and permitting description of their fundamental dynamical features such as limit cycle period, attractor structure, and transience length. These particular nonlinear automata generate multiple domains within which evolution exactly mimics that of the linear automaton, with the domain wall behaviour itself governed by the dynamics of the linear automaton. In particular, the position of the domain walls follows a trajectory that is determined by the linear system, and is characterized by an integer-valued 'winding number' representing the periodicity of its spatial behaviour. The limit cycle behaviour of the nonlinear automata on finite lattices is then determined by the periodicity of the associated linear 'template' system modulated by the winding numbers of the domain walls, and hence may viewed as providing a realization of quasiperiodicity in these discrete dynamical systems. RP JEN, E (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,MS-B258,LOS ALAMOS,NM 87545, USA. NR 12 TC 9 Z9 9 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-7715 J9 NONLINEARITY JI Nonlinearity PD MAY PY 1991 VL 4 IS 2 BP 251 EP 276 DI 10.1088/0951-7715/4/2/004 PG 26 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA FN490 UT WOS:A1991FN49000004 ER PT J AU CHRISTIANSEN, PL LOMDAHL, PS MUTO, V AF CHRISTIANSEN, PL LOMDAHL, PS MUTO, V TI ON A TODA LATTICE MODEL WITH A TRANSVERSAL DEGREE OF FREEDOM SO NONLINEARITY LA English DT Article ID THERMALLY GENERATED SOLITONS; NONLINEAR ELASTIC RODS; SOLITARY WAVES; DNA; APPROXIMATION; DYNAMICS; CHAIN AB A transversal degree of freedom is introduced in the Toda lattice. For different orders of magnitude of the longitudinal and transversal strains, coupled and uncoupled equations for these fields are derived in the discrete case as well as the continuum limit. Travelling wave solutions of the system are obtained and compared to numerical solutions. Standing waves, obtained by separation of variables, exhibit blow-up in finite time as well as bounded behaviour. C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP CHRISTIANSEN, PL (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545, USA. RI Christiansen, Peter /A-7978-2011 OI Christiansen, Peter /0000-0002-1465-9987 NR 29 TC 16 Z9 16 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-7715 J9 NONLINEARITY JI Nonlinearity PD MAY PY 1991 VL 4 IS 2 BP 477 EP 501 DI 10.1088/0951-7715/4/2/012 PG 25 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA FN490 UT WOS:A1991FN49000012 ER PT J AU ORTIZ, NR WHEELER, TA BREEDING, RJ HORA, S MEYER, MA KEENEY, RL AF ORTIZ, NR WHEELER, TA BREEDING, RJ HORA, S MEYER, MA KEENEY, RL TI USE OF EXPERT JUDGMENT IN NUREG-1150 SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article ID METHODOLOGY AB The explicit expert judgment process used in NUREG-1150, "Severe Accident Risks: An Assessment for Five US Nuclear Plants", is discussed in this paper. The main steps of the process are described, including selection of issues and experts, elicitation training, presentation of issues to the experts, preparation of issue analyses by the experts, discussion of issue analyses and elicitation, and recomposition and aggregation of results. To demonstrate the application of the expert judgment process to NUREG-1150, two issues are summarized: one from the accident frequency analysis, and one from the accident progression analysis. Recommendations and insights are provided to improve the use of explicit expert judgment in complex technical issues. C1 UNIV HAWAII,HILO,HI 96720. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87544. UNIV SO CALIF,LOS ANGELES,CA 90089. RP ORTIZ, NR (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 38 TC 31 Z9 31 U1 0 U2 3 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD MAY PY 1991 VL 126 IS 3 BP 313 EP 331 DI 10.1016/0029-5493(91)90023-B PG 19 WC Nuclear Science & Technology SC Nuclear Science & Technology GA FT748 UT WOS:A1991FT74800002 ER PT J AU EMMERT, GA POST, RF AF EMMERT, GA POST, RF TI D-HE-3 FUSION (REPORT ON THE 1ST WISCONSIN SYMPOSIUM, MADISON, WISCONSIN, UNITED-STATES-OF-AMERICA, 21-22 AUGUST 1990) SO NUCLEAR FUSION LA English DT Editorial Material C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP EMMERT, GA (reprint author), UNIV WISCONSIN,MADISON,WI 53706, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5 PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 1991 VL 31 IS 5 BP 981 EP 983 DI 10.1088/0029-5515/31/5/017 PG 3 WC Physics, Fluids & Plasmas SC Physics GA FR363 UT WOS:A1991FR36300017 ER PT J AU HOENEISEN, B ANDERSON, DF KWAN, S AF HOENEISEN, B ANDERSON, DF KWAN, S TI A CSI-TMAE PHOTOCATHODE WITH LOW-PRESSURE READOUT FOR RICH SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID DETECTOR; GAS; EFFICIENCY AB The operation of a CsI photocathode activated with an adsorbed layer of TMAE and coupled to a low-pressure wire chamber is presented. A quantum efficiency of 15% at wavelengths less than 190 nm, with single-step amplification gains of up to 10(7) and a signal width of 5 ns at the base were achieved. Ageing effects due to ion bombardment of the photocathode are discussed. C1 FERMI NATL ACCELERATOR LAB,PARTICLE DETECTOR GRP,BATAVIA,IL 60510. RP HOENEISEN, B (reprint author), UNIV SAN FRANCISCO QUITO,POB 841,SUC 12 OCTUBRE,QUITO,ECUADOR. NR 19 TC 25 Z9 25 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1991 VL 302 IS 3 BP 447 EP 454 DI 10.1016/0168-9002(91)90358-W PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FT406 UT WOS:A1991FT40600007 ER PT J AU BERMAN, LE HART, M AF BERMAN, LE HART, M TI ADAPTIVE CRYSTAL OPTICS FOR HIGH-POWER SYNCHROTRON SOURCES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB We report successful operation of the first X-ray monochromator with built-in correction for the thermal strain field created by a high power X-ray beam. The 27 pole wiggler magnet at the National Synchrotron Light Source provides a total power load of 330 W in a beam 60 mm wide. A (220) silicon monochromator system has been tested; the compensated deformation field contributes only 2 arc sec full width at half maximum intensity to the monochromator Darwin width of high order Bragg reflections. C1 UNIV MANCHESTER,DEPT PHYS,SCHUSTER LAB,MANCHESTER M13 9PL,LANCS,ENGLAND. RP BERMAN, LE (reprint author), BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973, USA. NR 6 TC 17 Z9 17 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1991 VL 302 IS 3 BP 558 EP 562 DI 10.1016/0168-9002(91)90375-Z PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FT406 UT WOS:A1991FT40600024 ER PT J AU LYNCH, GR DAHL, OI AF LYNCH, GR DAHL, OI TI APPROXIMATIONS TO MULTIPLE COULOMB SCATTERING SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article AB The width of the angular distribution of the multiple Coulomb scattering of relativistic heavy particles can be described by simple formulas. The familiar one, which uses the number of radiation lengths, is accurate to 34% for all Z and can be accurate to 11% if a logarithmic path length correction is included. A fairly simple representation that does not use the radiation length agrees with the predictions of Moliere scattering to 2%. RP LYNCH, GR (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 17 TC 143 Z9 152 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 58 IS 1 BP 6 EP 10 DI 10.1016/0168-583X(91)95671-Y PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FV652 UT WOS:A1991FV65200002 ER PT J AU YU, KM KATZ, B WU, IC BROWN, IG AF YU, KM KATZ, B WU, IC BROWN, IG TI FORMATION OF IRIDIUM SILICIDE LAYER BY HIGH-DOSE IRIDIUM ION-IMPLANTATION INTO SILICON SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID INTERFACE; GROWTH; SI AB We have investigated the formation of IrSi3 layers buried in (111) silicon. The layers are formed by iridium ion implantation at room temperature using a metal vapor vacuum arc (MEVVA) high current metal ion source with an average beam energy almost-equal-to 130 keV. Doses of the Ir ions ranging from 2 x 10(16) to 1.5 x 10(17)/cm2 were implanted into (111) Si. We have successfully formed a buried silicide layer in silicon by room temperature implantation and annealing. The formation of IrSi3 phase is realized after annealing at temperatures as low as 500-degrees-C. A continuous IrSi3 layer of almost-equal-to 200 angstrom thick buried under almost-equal-to 400 angstrom of Si was achieved with samples implanted with doses not less than 3.5 x 10(16)/cm2. Implanted doses above 8 x 10(16)/cm2 resulted in the formation of an IrSi3 layer on the surface due to excessive sputtering of Si by the Ir ions. The effects of implant dose on the phase formation mechanism, the interface morphology and the implanted atom redistribution are discussed. Radiation damage and regrowth of the Si due to the implantation process was also studied. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV ACCELERATOR & FUS RES,BERKELEY,CA 94720. RP YU, KM (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT & CHEM SCI,BERKELEY,CA 94720, USA. RI Yu, Kin Man/J-1399-2012 OI Yu, Kin Man/0000-0003-1350-9642 NR 19 TC 6 Z9 6 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 58 IS 1 BP 27 EP 33 DI 10.1016/0168-583X(91)95674-3 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FV652 UT WOS:A1991FV65200005 ER PT J AU ROSSEEL, TM YOUNG, JP VANE, CR ZUHR, RA PETERSON, RS AF ROSSEEL, TM YOUNG, JP VANE, CR ZUHR, RA PETERSON, RS TI HIGH-RESOLUTION HEAVY-ION-INDUCED X-RAY-SATELLITE EMISSION STUDY OF IMPLANTED SULFUR AS A PROBE OF CO-IMPLANTED OXYGEN IN AN OXIDE SUBSTRATE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID CHEMICAL ENVIRONMENT AB Using high-resolution measurements, the relative fluorescence yields of the sulfur K-alpha L(n) X-ray satellite lines produced by 24 MeV Si(q+) ion irradiation of a series of quartz glass targets co-implanted to equal doses and depths of sulfur and oxygen have been obtained and compared to the yields from targets implanted to the same depth with sulfur only. The data exhibit lower yields in the higher-order KL(n) satellite lines for the co-implanted oxygen targets but similar dose dependent curves. These results are consistent with oxygen increasing the valence electron density of the local sulfur environment. They also suggest that, with an appropriate choice of a probe ion, HIXSE may be capable of detecting impurity ions in matrices that normally mask the impurity, e.g., oxygen in oxide substrates. C1 UNIV SOUTH,DEPT PHYS,SEWANEE,TN 37375. RP ROSSEEL, TM (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. RI Rosseel, Thomas/J-4086-2016 OI Rosseel, Thomas/0000-0001-9917-7073 NR 13 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 41 EP 44 DI 10.1016/0168-583X(91)95966-H PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800015 ER PT J AU BIEDERMANN, C LEVIN, JC SHORT, RT ELSTON, SB GIBBONS, JP KIMURA, K KELLER, N SELLIN, IA CEDERQUIST, H ANDERSSON, LR ANDERSSON, H LILJEBY, L AF BIEDERMANN, C LEVIN, JC SHORT, RT ELSTON, SB GIBBONS, JP KIMURA, K KELLER, N SELLIN, IA CEDERQUIST, H ANDERSSON, LR ANDERSSON, H LILJEBY, L TI ANGULAR-DISTRIBUTIONS OF SINGLE-ELECTRON AND DOUBLE-ELECTRON CAPTURE IN VERY-SLOW AR6+-AR COLLISIONS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID ENERGY-GAIN SPECTROSCOPY; NE; AR AB We have measured state-resolved angular distributions of one- and two- electron capture in 32 to 800 eV Ar6+-Ar collisions. The experimental energy-gain spectra show that single-electron capture mainly populates the 5s, 5p and 4f levels. We observe detailed structures in the corresponding angular distributions, but a final interpretation has to await a quantitative analysis of the collision dynamics. We tentatively ascribe the main features in the angular distribution of true double-electron capture at Q approximately 26 eV (4s4f and 4s5s) and Q approximately 42 eV (3d4d) to processes involving two consecutive one-electron transitions. For the transfer ionization process, we measure a Q-value of approximately 26 eV, which we assign to autoionizing 4s5s (or 4s4f) levels. The 4s5s, 4s4f, and 3d4d levels all reside above the first ionization limit of Ar4+, but we find that the 3d4d level stabilizes through radiative decay. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. MANNE SIEGBAHN INST PHYS,S-10405 STOCKHOLM,SWEDEN. RP BIEDERMANN, C (reprint author), UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996, USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 74 EP 77 DI 10.1016/0168-583X(91)95975-J PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800024 ER PT J AU HAVENER, CC NESNIDAL, MP PORTER, MR PHANEUF, RA AF HAVENER, CC NESNIDAL, MP PORTER, MR PHANEUF, RA TI ELECTRON-CAPTURE BY MULTICHARGED IONS FROM HYDROGEN-ATOMS AT EV ENERGIES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID CHARGE-TRANSFER; CROSS-SECTIONS; MERGED-BEAMS; COLLISIONS; O-3+ AB To quantitatively study electron capture during collisions of multiply charged ions with neutral atoms at near-thermal energies, keV-energy multicharged ion beams are merged with ground-state beams of H or D atoms of chosen velocity such that collisions in the relative energy range 1-1000 eV/amu result. Recent data for O3+, O4+ + H(D) are presented and compared with theoretical predictions. Recently completed modifications to the apparatus are described that will provide a significant improvement in signal-to-background and angular collection. These improvements will allow measurements to be extended to lower energies, where effects due to the ion-induced dipole attraction may be evident. RP HAVENER, CC (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 14 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 95 EP 98 DI 10.1016/0168-583X(91)95980-R PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800029 ER PT J AU KIMURA, M SATO, H MATSUZAWA, M AF KIMURA, M SATO, H MATSUZAWA, M TI 2-ELECTRON EXCITATION IN SLOW ION-ATOM COLLISIONS - INTERFERENCE AMONG AUTOIONIZING STATES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID LOW-ENERGY COLLISIONS; HE AB Structures found in the Auger electron energy distribution that are due to interferences resulting from collisions of H+ ions with He atoms below 5 keV are theoretically studied within a close-coupling scheme based on molecular representation. The present study identifies the dominant interference-related contributors to the structures. These contributors are due to the interferences between (i) different autoionizing electronic states, (ii) incoming and outgoing parts of collisions on a single trajectory, (iii) different locations that have the same ejected electron energy on a single trajectory, and (iv) different trajectories. C1 UNIV ELECTROCOMMUN,DEPT APPL PHYS,CHOFU,TOKYO 182,JAPAN. RICE UNIV,DEPT PHYS,HOUSTON,TX 77254. RP KIMURA, M (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 121 EP 123 DI 10.1016/0168-583X(91)95986-N PN 1 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800035 ER PT J AU LEVIN, JC BIEDERMANN, C KELLER, N LILJEBY, L SHORT, RT SELLIN, IA LINDLE, DW AF LEVIN, JC BIEDERMANN, C KELLER, N LILJEBY, L SHORT, RT SELLIN, IA LINDLE, DW TI PHOTOION AUGER-ELECTRON COINCIDENCE MEASUREMENTS NEAR THRESHOLD SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID SYNCHROTRON RADIATION BEAMLINE; HIGH-ENERGY-RESOLUTION; PHOTOELECTRON RECAPTURE; ARGON; SATELLITES AB The vacancy cascade which fills an atomic inner-shell hole is a complex process which can proceed by a variety of paths, often resulting in a broad distribution of photoion charge states. We have measured simplified argon photoion charge distributions by requiring a coincidence with a F-LL or K-LM Auger electron, following K excitation with synchrotron radiation, as a function of photon energy, and report here in detail the argon charge distributions coincident with K-L1L23 Auger electrons. The distributions exhibit a much more pronounced photon-energy dependence than do the more complicated non-coincident spectra. Resonant excitation of the K electron to np levels, shakeoff of these np electrons by subsequent decay processes, double-Auger decay, and recapture of the K photoelectron through postcollision interaction occur with significant probability. C1 OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. RP UNIV TENNESSEE, DEPT PHYS, KNOXVILLE, TN 37996 USA. NR 17 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 124 EP 128 DI 10.1016/0168-583X(91)95987-O PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800036 ER PT J AU SHAFROTH, SM MCDONALD, F BENHENNI, M KESSEL, QC DEVENEY, E SWENSON, JK SCHULZ, M GIESE, JP SCHONE, H DATZ, S DITTNER, PF KRAUSE, HF VANE, CR JONES, N BECHTHOLD, U HENDRICK, LD PETERSON, DM AF SHAFROTH, SM MCDONALD, F BENHENNI, M KESSEL, QC DEVENEY, E SWENSON, JK SCHULZ, M GIESE, JP SCHONE, H DATZ, S DITTNER, PF KRAUSE, HF VANE, CR JONES, N BECHTHOLD, U HENDRICK, LD PETERSON, DM TI EXCITATION CURVE FOR AUGER DECAY OF THE (1S2S2P2)D-3 STATE OF C-2+ FORMED THROUGH RTE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID ION-ATOM COLLISIONS; RESONANT TRANSFER; HE AB The ORNL EN tandem supplied beams of 3.5-9 MeV C3+ ions which were incident on a differentially pumped He target. Auger electrons emitted by fast C2+ ions emerged at 10-degrees (lab) w.r.t. the incident ion beam. They were detected using a two stage spectrometer with kinematic refocusing. An excitation curve was obtained for the (1s2s2p2)3D state Auger decay to the ground state of C3+. The excitation curve peaks at approximately 6 MeV, which strongly supports the notion that the state is formed through resonant transfer and excitation. C1 UNIV CONNECTICUT,STORRS,CT 06269. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. FRANCES MARION COLL,FLORENCE,SC 29501. RP SHAFROTH, SM (reprint author), UNIV N CAROLINA,CHAPEL HILL,NC 27599, USA. 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 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 129 EP 131 DI 10.1016/0168-583X(91)95988-P PN 1 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800037 ER PT J AU VANEMMICHOVEN, PAZ HAVENER, CC MEYER, FW ZEHNER, DM AF VANEMMICHOVEN, PAZ HAVENER, CC MEYER, FW ZEHNER, DM TI ELECTRON-EMISSION DURING MULTICHARGED ION-SURFACE INTERACTIONS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID HIGHLY CHARGED IONS; METAL-SURFACE; NEUTRALIZATION AB Recent measurements of electron spectra for slow multicharged N ion-surface collisions are presented. The emphasis is on potential emission, i.e., the electron emission related to the neutralization of the ions. When using N ions that carry a K shell vacancy into the collision, characteristic K Auger electron emission from the projectiles is observed as well as, for specific surfaces, target atom Auger transitions (resulting from vacancy transfer). Measurements of the intensity of these Auger transitions as a function of the time the ions spend above the surface can serve as a useful probe of the timescales characterizing the relevant neutralization processes. This technique is elucidated with the help of some computer simulations. It is shown that neutralization timescales required in the atomic ladder picture, in which neutralization takes place by resonant capture followed by purely intra-atomic Auger transitions, are too long to explain our experimental results. The introduction of additional neutralization/de-excitation mechanisms in the simulations leads to much better agreement with the experiments. C1 JOINT INST HEAVY ION RES,HOLIFIELD HEAVY ION RES FACIL,OAK RIDGE,TN 37831. RP VANEMMICHOVEN, PAZ (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 11 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 136 EP 139 DI 10.1016/0168-583X(91)95990-U PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800039 ER PT J AU CHEN, MH AF CHEN, MH TI EFFECTS OF RELATIVITY ON RTEX IN COLLISIONS OF UQ+ WITH LIGHT TARGETS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID RESONANT-TRANSFER-EXCITATION; ION-ATOM COLLISIONS; + AR COLLISIONS; X-RAY; ELECTRON-CAPTURE; CROSS-SECTIONS; CA-17+; AUGER; BREIT; H-2 AB We have calculated the resonant transfer and excitation cross sections in collisions of U(q+) (q = 82, 89 and 90) ions with H2, He and C in impulse approximation using the multiconfiguration Dirac-Fock method. The calculations were carried out in intermediate coupling with configuration interaction. The quantum electrodynamic and finite nuclear size corrections were included in the calculations of transition energies. The Auger rates were calculated including the contributions from Coulomb as well as the transverse Breit interactions. For U89+ and U90+, effects of relativity not only shift the peak positions but also change the peak structure. The total dielectronic recombination strength has been found to increase by 50% due to the effects of relativity. The present theoretical RTEX cross sections for U90+ in hydrogen agree well with experiment. For U82+, Breit interaction has been found to have little effect on the RTEX cross sections involving L-shell excitation. However, the spin-orbit interaction can still make a significant change in the peak structure. RP CHEN, MH (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DIV HIGH TEMP PHYS,LIVERMORE,CA 94550, USA. NR 27 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 149 EP 153 PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800042 ER PT J AU DEVENEY, EF KESSEL, QC SCHONE, H JONES, NL MCDONALD, FS SHAFROTH, SM AF DEVENEY, EF KESSEL, QC SCHONE, H JONES, NL MCDONALD, FS SHAFROTH, SM TI ELECTRON-EMISSION FROM 3.0 MEV BR-KR COLLISIONS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID HEAVY-IONS; XE TARGETS; CONTINUUM; ATOMS; SPECTRA AB The electron emission spectra observed following low-MeV collisions of heavy ions with heavy atoms are often dominated by electrons with a continuous range of energies. For example, the electron emission spectra from Kr-Kr and Kr-Xe collisions are dominated by a continuous portion that extends from low energies to nearly 1000 eV. For the Kr-Kr case, there is evidence that the continuous portion of the spectrum results from the emission of 20-24 electrons from the two-ion system prior to the time L-Auger emission takes place and that many of the emitted electrons have energies in the range of 25-500 eV. The present data were obtained for the closely related Br-Kr system with a high-resolution electron spectrometer to see whether discrete lines could be resolved and if they could, whether they would comprise the major portion of the spectrum or appear as lines superimposed upon the continuum. The experiment resolved only a few peaks and they appear to be superimposed upon a continuum of different origin. C1 UNIV CONNECTICUT,INST MAT SCI,STORRS,CT 06269. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. UNIV N CAROLINA,DEPT PHYS & ASTRON,CHAPEL HILL,NC 27599. RP DEVENEY, EF (reprint author), UNIV CONNECTICUT,DEPT PHYS,STORRS,CT 06269, USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 173 EP 175 DI 10.1016/0168-583X(91)95999-T PN 1 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800048 ER PT J AU QUICK, CR DONAHUE, JB COHEN, S BRYANT, HC TANG, CY HARRIS, PG MOHAGHEGHI, AH REEDER, RA SHARIFIAN, H TOUTOUNCHI, H SMITH, WW AF QUICK, CR DONAHUE, JB COHEN, S BRYANT, HC TANG, CY HARRIS, PG MOHAGHEGHI, AH REEDER, RA SHARIFIAN, H TOUTOUNCHI, H SMITH, WW TI PHOTODETACHMENT OF THE H- ION SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID SPREAD; BEAM AB Detachment of electrons from the H- ion is investigated with an experimental technique whereby an H- beam moving at a relativistic velocity (2.5 x 10(10) cm/s) is intersected with a fixed frequency laser. The Doppler effect allows systematic variation of the center-of-mass (CM) photon energy over a wide range (factor of 10) by simply adjusting the angle between the ion and laser beams. The focused output from a pulsed, linearly polarized, CO2 TEA laser operating at 10.6-mu-m, with peak intensities on the order of 10 GW/cm2, was used to examine the multiphoton absorption process in H-. The fourth harmonic (266 nm) of a Nd:YAG laser was used to investigate some of the doubly-excited state resonances in H-. In the multiphoton absorption work, electron detachment was observed at photon energies where as few as 2 and as many as 8 photons are required to get above the 1-electron detachment threshold (EDT) of H- (0.754 eV). Electron yield vs photon energy plots exhibit structure that is laser intensity dependent. Electron yield vs laser pulse energy data was obtained at a few selected CM wavelengths and laser pulse energies. In the single-photon UV laser work, numerous resonances within the H- photodetachment continuum corresponding to one-photon two-electron excitation processes were observed. The doubly-excited resonances appear to be of the Feshbach type. A simple, semi-empirical recursion formula predicts the resonance energy levels. The experimental techniques described here can be used to accurately determine accelerator beam and ion source parameters such as beam energy, energy-spread, and ion density spatial distribution. C1 UNIV NEW MEXICO,ALBUQUERQUE,NM 87131. UNIV CONNECTICUT,STORRS,CT 06269. RP QUICK, CR (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 205 EP 210 DI 10.1016/0168-583X(91)96007-8 PN 1 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800056 ER PT J AU THOMPSON, JS PEGG, DJ DELLWO, J COMPTON, RN ALTON, GD AF THOMPSON, JS PEGG, DJ DELLWO, J COMPTON, RN ALTON, GD TI PHOTODETACHMENT OF METASTABLE HE- SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID CROSS-SECTIONS AB A crossed-beams apparatus has been used to measure angular distributions and cross sections for photoelectron detachment from metastable He-. Energy- and angle-resolved electron spectroscopy was used to investigate the spectral dependences of the angular distribution of the photoelectrons. The angular distributions along with photoelectron yield measurements were used to determine the cross sections for photodetachment of He- (2(4)P) via the energy resolved He(2(3)P) and He(2(3)S) exit channels. The precision of the cross section measurements was enhanced by exploiting the kinematic effects associated with detachment from a fast beam source. Calculated cross sections for the photodetachment of H- were used to establish an absolute scale for the He- cross section measurements. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP THOMPSON, JS (reprint author), UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996, USA. OI Thompson, Jeffrey/0000-0001-9699-5767 NR 14 TC 1 Z9 1 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 211 EP 215 DI 10.1016/0168-583X(91)96008-9 PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800057 ER PT J AU DELGRANDE, NK BEIERSDORFER, P HENDERSON, JR OSTERHELD, AL SCOFIELD, JH SWENSON, JK AF DELGRANDE, NK BEIERSDORFER, P HENDERSON, JR OSTERHELD, AL SCOFIELD, JH SWENSON, JK TI ION TRAP MEASUREMENT OF U-64+ X-RAY TRANSITION SPECTRA SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID HIGHLY CHARGED IONS; EMISSION RATES; NICKEL AB Highly-charged uranium ions with a dominant nickel-like component (U64+) were produced using the electron beam ion trap (EBIT) with an electron bombardment energy of 7.4 keV. A comparison of the measured n = 4 to n = 3 X-ray transition spectra with calculations for U64+ gave excellent qualitative agreement. The low-energy region of the 4-3 spectrum for the Ni-like ions was characterized by a strong electric quadrupole 4s-3d transition, about as large as the leading dipole 4f-3d transition, which tagged the abundance of U64+ ions. High resolution spectroscopy was used to measure 4f-3d transition energies for ten charge states: U60+-U69+ excited by 6.4-8.9 keV electrons. The ionization balance for 8.9 keV electron excitation was mostly from five charge states, U64+-U68+, in qualitative agreement with a separate analysis of extracted ions. RP DELGRANDE, NK (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 18 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 227 EP 231 DI 10.1016/0168-583X(91)96012-A PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800061 ER PT J AU ANDERSSON, LR BARANY, A CEDERQUIST, H BIEDERMANN, C AF ANDERSSON, LR BARANY, A CEDERQUIST, H BIEDERMANN, C TI ANGULAR SCATTERING IN LOW-ENERGY COLLISIONS INVOLVING MULTICHARGED IONS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID SINGLE-ELECTRON-CAPTURE; 2-ELECTRON CAPTURE; AR4+-AR COLLISIONS; CROSS-SECTIONS; HE; DISTRIBUTIONS AB Calculations of angular differential cross sections in charge exchange collisions between Ar6+ and He in the 1.6-25 eV/u energy range have been performed. Results from a fully quantal model potential method and from a classical trajectory multichannel Landau-Zener (MCLZ) method are compared. Allowing for singly excited states on Ar5+, and after convolution with a typical experimental resolution, the two methods are in fair agreement. Recent experimental results do not, however, support the theoretical findings at the lowest energies. We propose that population of final states of the type 3s3p3d on Ar5+, which were not included in the original calculations, are the reason for this discrepancy. A MCLZ calculation including these channels gives support to this hypothesis. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. RP ANDERSSON, LR (reprint author), MANNE SIEGBAHN INST PHYS,FRESCATIVAGEN 24,S-10405 STOCKHOLM,SWEDEN. NR 14 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 246 EP 249 DI 10.1016/0168-583X(91)96016-E PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800065 ER PT J AU SWENSON, JK BURGDORFER, J MEYER, FW HAVENER, CC GREGORY, DC STOLTERFOHT, N AF SWENSON, JK BURGDORFER, J MEYER, FW HAVENER, CC GREGORY, DC STOLTERFOHT, N TI COULOMB PATH INTERFERENCE IN LOW-ENERGY HE+ + HE COLLISIONS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID ION ATOM COLLISIONS; TRANSITIONS; EMISSION AB Coulomb "path" interference results from the existence of two trajectories, indistinguishable with respect to laboratory energy and emission angle, along which ejected autoionizing electrons may be scattered by the attractive Coulomb potential of the slowly receding spectator ion. Experimental evidence for this new phenomenon exists in the uncharacterestically rapid angular dependence of the postcollision broadened lineshape of the He target 2s21S autoionizing state measured near 0-degrees following 10 keV He+ + He collisions. We present a semiclassical model for this effect in which we account for the path dependence of the amplitude of the ejected electron following decay of the autoionizing state. Calculated model lineshape, which include contributions from adjacent overlapping resonances, are found to be in excellent agreement with the angular dependence observed in the data. Similar interference structure is observed in the calculated lineshape for a single isolated 2s21S resonance. C1 UNIV TENNESSEE,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP SWENSON, JK (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. 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 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 295 EP 299 DI 10.1016/0168-583X(91)96030-O PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800079 ER PT J AU TANIS, JA BERNSTEIN, EM CHANTRENNE, S CLARK, MW ELLISON, T FOSTER, CC GRAHAM, WG JACOBS, WW MOWAT, JR RINCKEL, T ROSS, A SCHNEIDER, D STOCKLI, MP BADNELL, NR AF TANIS, JA BERNSTEIN, EM CHANTRENNE, S CLARK, MW ELLISON, T FOSTER, CC GRAHAM, WG JACOBS, WW MOWAT, JR RINCKEL, T ROSS, A SCHNEIDER, D STOCKLI, MP BADNELL, NR TI DIELECTRONIC RECOMBINATION IN HE+ IONS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID SHELL RESONANT TRANSFER; CROSS-SECTIONS; EXCITATION; OXYGEN; COOLER AB Dielectronic recombination involving 1s+e- --> nln'l' transitions has been investigated for He+ ions. This work was done using the ion storage ring and electron cooler at the Indiana University Cyclotron Facility. Resonant maxima from DR were observed, but the energy resolution was insufficient to identify individual transitions. The magnitude of the measured cross sections appears to be about a factor of two lower than theory. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. QUEENS UNIV BELFAST,BELFAST BT7 1NN,ANTRIM,NORTH IRELAND. N CAROLINA STATE UNIV,RALEIGH,NC 27695. KANSAS STATE UNIV AGR & APPL SCI,MANHATTAN,KS 66506. AUBURN UNIV,AUBURN,AL 36849. RP TANIS, JA (reprint author), WESTERN MICHIGAN UNIV,KALAMAZOO,MI 49008, USA. OI Graham, William/0000-0003-2759-4657 NR 22 TC 10 Z9 10 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 337 EP 339 DI 10.1016/0168-583X(91)96041-I PN 1 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800090 ER PT J AU PITARKE, JM ECHENIQUE, PM RITCHIE, RH AF PITARKE, JM ECHENIQUE, PM RITCHIE, RH TI DEPENDENCE OF KNOCK-ON COLLISION ELECTRON-EMISSION ON THE ORIENTATION OF FAST DICLUSTERS IN SOLIDS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID SWIFT IONS; STATES; WAKE; EXCITATION AB The cluster-orientation dependence of the emitted knock-on collision electron distributions when fast diclusters interact with condensed matter is investigated. The scattering by each centre of the dicluster is described by means of the phase shifts of a velocity dependent Yukawa potential describing the dynamic screening, and the multiple scattering effects are approximated within the second Born approximation. The applicability of this approximation as the charges and velocities of the diclusters are changed is also discussed, and numerical comparisons of our results with experiment are made. C1 EUSKAL HERRIKO UNIBERTSITATEA,FAC CHEM,DEPT MAT FIS,E-20080 DONOSTIA,SPAIN. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. RP PITARKE, JM (reprint author), EUSKAL HERRIKO UNIBERTSITATEA,FAC SCI,DEPT THEORET PHYS,644 POSTA KUTXATILA,E-48080 BILBAO,SPAIN. RI Pitarke, Jose/C-8602-2009 OI Pitarke, Jose/0000-0002-8253-8028 NR 20 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 369 EP 374 DI 10.1016/0168-583X(91)96050-U PN 1 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800099 ER PT J AU JACKSON, A AF JACKSON, A TI THE ADVANCED LIGHT-SOURCE AT THE LAWRENCE-BERKELEY-LABORATORY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB The Advanced Light Source (ALS), a national facility currently under construction at the Lawrence Berkeley Laboratory (LBL), is a third-generation synchrotron light source designed to produce extremely bright beams of synchrotron radiation, in the energy range from a few eV to 10 keV. The design is based on a 1-1.9 GeV electron storage ring (optimized at 1.5 GeV), and utilizes special magnets, known as undulators and wigglers (collectively referred to as insertion devices), to generate the radiation. In this paper we describe the main accelerator components of the ALS, the variety of insertion devices, the radiation spectra expected from these devices, and the complement of experiments that have been approved for initial operation, starting in April 1993. RP JACKSON, A (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 5 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 375 EP 378 DI 10.1016/0168-583X(91)96051-L PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800100 ER PT J AU KRAVIS, SD CHURCH, DA JOHNSON, BM LEVIN, JC AZUMA, Y SELLIN, IA MERON, M JONES, KW DRUETTA, M MANSOUR, N BERRY, HG SHORT, RT AF KRAVIS, SD CHURCH, DA JOHNSON, BM LEVIN, JC AZUMA, Y SELLIN, IA MERON, M JONES, KW DRUETTA, M MANSOUR, N BERRY, HG SHORT, RT TI SEQUENTIAL PHOTOIONIZATION OF IONS USING SYNCHROTRON RADIATION AND A PENNING ION TRAP SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID HIGHLY-CHARGED IONS AB Sequential photoionization has the potential of making available for study highly charged low energy ions. Synchrotron radiation was used to create a multicharged xenon ion target for further ionization by synchrotron radiation inside a Penning ion trap. Evidence of sequential photoionization was seen, though the yields were small. Improvements in the apparatus and radiation from third generation synchrotrons are expected to increase sequential photoionization yields significantly. C1 ARGONNE NATL LAB, DIV PHYS, ARGONNE, IL 60439 USA. UNIV ST ETIENNE, TSI LAB, CNRS, UA 842, F-42100 ST ETIENNE, FRANCE. BROOKHAVEN NATL LAB, UPTON, NY 11973 USA. UNIV TENNESSEE, DEPT PHYS, KNOXVILLE, TN 37996 USA. OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. RP TEXAS A&M UNIV SYST, DEPT PHYS, COLLEGE STN, TX 77843 USA. NR 9 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 396 EP 399 DI 10.1016/0168-583X(91)96056-Q PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800105 ER PT J AU ROBINSON, AL SCHLACHTER, AS AF ROBINSON, AL SCHLACHTER, AS TI RESEARCH OPPORTUNITIES AT THE ADVANCED LIGHT-SOURCE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID SYNCHROTRON RADIATION AB The Advanced Light Source (ALS), now under construction at the Lawrence Berkeley Laboratory, is a third-generation synchrotron radiation facility based on a low-emittance, 1.5-GeV electron storage ring with ten long straight sections available for insertion devices and, initially, 24 bend-magnet ports. Undulators will provide high-brightness radiation at photon energies from below 10 eV to above 2 keV; wiggler and bend-magnet radiation will extend the spectral coverage with high fluxes to above 10 keV. Scheduled to begin operations as a US Department of Energy national user facility in the spring of 1993, the ALS will support an extensive research program in which soft X-ray and ultraviolet radiation is used to study matter in all its varied gaseous, liquid, and solid forms. Participating research teams to implement the initial scientific program have been selected. RP ROBINSON, AL (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV ADV LIGHT SOURCE ACCELERATOR & FUS RES,BERKELEY,CA 94720, USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 413 EP 416 DI 10.1016/0168-583X(91)96060-X PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800109 ER PT J AU CHURCH, DA KRAVIS, SD JOHNSON, BM AZUMA, Y LEVIN, J SELLIN, IA MERON, M JONES, KW DRUETTA, M MANSOUR, N BERRY, HG SHORT, RT AF CHURCH, DA KRAVIS, SD JOHNSON, BM AZUMA, Y LEVIN, J SELLIN, IA MERON, M JONES, KW DRUETTA, M MANSOUR, N BERRY, HG SHORT, RT TI ELECTRON-TRANSFER COLLISION STUDIES ON STORED IONS PRODUCED BY SYNCHROTRON RADIATION SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID RELAXATION AB Studies of electron transfer collisions of low energy stored ions with target atoms have been carried out as a function of the well depth of the Penning ion trap. The ions were produced by vacancy cascades following inner-shell photoionization by synchrotron radiation. The ion storage data, following an analysis based on the details of the ion production, storage, and collision processes in the trap, provides information for optimizing the accuracy of electron transfer rate coefficient measurements when several charge state are present. Low trap well depths exceeding a well-defined minimum value are the most useful. C1 UNIV ST ETIENNE,TSI LAB,CNRS,UA 842,F-42100 ST ETIENNE,FRANCE. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP CHURCH, DA (reprint author), TEXAS A&M UNIV SYST,DEPT PHYS,COLLEGE STN,TX 77843, 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 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 417 EP 421 DI 10.1016/0168-583X(91)96061-O PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800110 ER PT J AU KELLER, R AF KELLER, R TI SURVEY AND ALIGNMENT OF THE ADVANCED LIGHT-SOURCE IN BERKELEY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB The general survey and alignment concept for the Advanced Light Source (ALS) at LBL Berkeley [1] is based on a network of fixed monuments to which all component positions are referred. Observations include electronic distance measurements and direction sightings with electronic data capture; data are processed by a customized version of the computer code PC-GEONET [2] which provides raw data reduction, calculation of adjusted coordinates, and error analysis. Additionally, for local survey tasks the commercial software package ECDCS [3] is used. In this paper, the ALS survey and alignment strategy and techniques are presented and critically discussed; first experiences with alignment of the linac and booster components are described. RP KELLER, R (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV ACCELERATOR & FUS RES,BERKELEY,CA 94720, USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 422 EP 426 DI 10.1016/0168-583X(91)96062-P PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800111 ER PT J AU JONES, KW SPANNE, P WEBB, SW CONNER, WC BEYERLEIN, RA REAGAN, WJ DAUTZENBERG, FM AF JONES, KW SPANNE, P WEBB, SW CONNER, WC BEYERLEIN, RA REAGAN, WJ DAUTZENBERG, FM TI CATALYST ANALYSIS USING SYNCHROTRON X-RAY MICROSCOPY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB Synchrotron X-ray microscopy techniques have been used to characterize several different types of heterogeneous catalysts. Using a collimator to produce microbeams with a size of less than 10-mu-m, maps of the elemental distributions based on detection of the fluorescent X-rays were made, and computed microtomography (CMT) techniques were applied to produce "phase/density contrast" maps. CMT techniques were also used to determine the distribution of a specific major element by making measurements above and below the K X-ray absorption edge. The measurements were made using bending magnet radiation and, in one case, radiation from a 4 T superconducting wiggler at the National Synchrotron Light Source. Examples of applications to the study of polyethylene polymerization particles, fluid catalytic cracking catalysts, and hydrotreating catalysts are given. C1 UNIV MASSACHUSETTS,AMHERST,MA 01003. AMOCO OIL CO,NAPERVILLE,IL 60566. CATALYT ASSOCIATES,MT VIEW,CA 94043. RP JONES, KW (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 6 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 427 EP 432 DI 10.1016/0168-583X(91)96063-Q PN 1 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800112 ER PT J AU JOHNSON, BM AF JOHNSON, BM TI ATOMIC PHYSICS RESEARCH WITH 2ND-GENERATION AND 3RD-GENERATION SYNCHROTRON LIGHT-SOURCES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB This contribution to these proceedings is intended to provide an introduction and overview for other contributions on atomic (and related) physics research at existing and planned synchrotron light sources. The emphasis will be on research accomplishments and future opportunities, but a comparison will be given of operating characteristics for first, second-, and third-generation machines. First-generation light sources were built to do research with the primary electron and positron beams, rather than with the synchrotron radiation itself. Second-generation machines were specifically designed to be dedicated synchrotron-radiation facilities, with an emphasis on the use of bending-magnet radiation. The new third-generation light sources are being designed to optimize radiation from insertion devices, such as undulators and wigglers. Each generation of synchrotron light source offers useful capabilities for forefront research in atomic physics and many other disciplines. RP JOHNSON, BM (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 27 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 433 EP 437 DI 10.1016/0168-583X(91)96064-R PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800113 ER PT J AU VONWIMMERSPERG, U JONES, KW MCKENZIEWILSON, RB WARD, TE SNEAD, CL AF VONWIMMERSPERG, U JONES, KW MCKENZIEWILSON, RB WARD, TE SNEAD, CL TI ATOMIC PHYSICS WITH RELATIVISTIC ION-BEAMS, USING THE BROOKHAVEN 200 MEV LINAC AND 1.5 GEV BOOSTER SYNCHROTRON SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB A survey of atomic physics experiments with relativistic ion beams at the Brookhaven Neutral Beam Test Facility is presented and special techniques using 150 m flight paths and precision particle and laser beam optics are described. RP VONWIMMERSPERG, U (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 438 EP 440 DI 10.1016/0168-583X(91)96065-S PN 1 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800114 ER PT J AU NELSON, RO LAYMON, CM WENDER, SA AF NELSON, RO LAYMON, CM WENDER, SA TI HIGH-RESOLUTION INELASTIC GAMMA-RAY MEASUREMENTS WITH A WHITE NEUTRON SOURCE FROM 1 TO 200 MEV SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB Measurements of prompt gamma rays following neutron-induced reactions have recently been made at the spallation neutron source at the WNR target area of LAMPF using germanium detectors. These experiments provide extensive excitation function data for inelastic neutron scattering as well as for other reactions such as (n, alpha), (n, n-alpha), (n, p), (n, np), (n, nnp) and (n, xn) for 1 less-than-or-equal-to x less-than-or-equal-to 11. The continuous energy coverage available from 1 MeV to over 200 MeV is ideal for excitation function measurements and greatly extends the energy range for such data. The results of these measurements will provide a database for interpretation of gamma-ray spectra from the planned Mars Observer mission, aid in radiation transport calculations, allow verification of nuclear reaction models, and improve the evaluated neutron reaction database. RP NELSON, RO (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 6 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 451 EP 454 DI 10.1016/0168-583X(91)96068-V PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800117 ER PT J AU BROWN, RE CAMP, JB DARLING, TW AF BROWN, RE CAMP, JB DARLING, TW TI ANTIMATTER GRAVITY EXPERIMENT SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID MASS; LAW AB An experiment is being developed to measure the acceleration of the antiproton in the gravitational field of the earth. Antiprotons of a few MeV from the LEAR facility at CERN will be decelerated, captured, cooled to a temperature of about 10 K, and subsequently launched a few at a time into a drift tube where the effect of gravity on their motion will be determined by a time-of-flight method. Development of the experiment is proceeding at Los Alamos using normal matter. The fabrication of a drift tube that will produce a region of space in which gravity is the dominant force on moving ions is of major difficulty. This involves a study of methods of minimizing the electric fields produced by spatially varying work functions on conducting surfaces. Progress in a number of areas is described, with emphasis on the drift-tube development. RP BROWN, RE (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 28 TC 12 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 480 EP 483 DI 10.1016/0168-583X(91)96075-V PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800124 ER PT J AU TOTH, KS NITSCHKE, JM VIERINEN, KS WILMARTH, PA FIRESTONE, RB KORTELAHTI, MO AF TOTH, KS NITSCHKE, JM VIERINEN, KS WILMARTH, PA FIRESTONE, RB KORTELAHTI, MO TI SPECTROSCOPY OF PROTON-RICH NUCLEI IN THE RARE-EARTH REGION SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID ALPHA-DECAY; ENERGIES; ISOMERS; TM-153; STATES AB The isotope separator facility OASIS, on-line at the Lawrence Berkeley Laboratory Super-HILAC, was used to investigate proton-rich rare earth nuclei. Single-particle states near the 32-neutron shell were delineated, numerous new isotopes, isomers and beta-delayed proton emitters were discovered and the alpha-decay properties of some nuclides with N greater-than-or-equal-to 84 were re-examined. In this contribution the experimental program is summarized briefly, the excitation energies of the S1/2 and h11/2 proton states in this mass region are discussed, and results on the beta-delayed-proton spectra of 145Dy and 147Er are presented. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. LOUISIANA STATE UNIV,BATON ROUGE,LA 70803. RP TOTH, KS (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. OI Firestone, Richard/0000-0003-3833-5546 NR 17 TC 1 Z9 1 U1 2 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 484 EP 488 DI 10.1016/0168-583X(91)96076-W PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800125 ER PT J AU BECKER, JA HENRY, EA YATES, SW WANG, TF KUHNERT, A BRINKMAN, MJ CIZEWSKI, JA DELEPLANQUE, MA DIAMOND, RM STEPHENS, FS AZAIEZ, F KORTEN, W DRAPER, JE AF BECKER, JA HENRY, EA YATES, SW WANG, TF KUHNERT, A BRINKMAN, MJ CIZEWSKI, JA DELEPLANQUE, MA DIAMOND, RM STEPHENS, FS AZAIEZ, F KORTEN, W DRAPER, JE TI VERY ELONGATED NUCLEI NEAR A = 194 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID SUPERDEFORMED BANDS; ALIGNMENT; LINE AB A gamma-ray cascade in Hg-191 of 12 members with average energy spacing 37 keV and Q(t) = 18(3) eb was reported by Moore and co-workers in 1989. This was the first report of very elongated nuclei (superdeformation) in this mass region. Since then, some 25 gamma-ray cascades have been observed in 11 (slightly neutron deficient) Hg, Pb and Tl nuclei. Our collaboration has investigated 7 of these nuclei. The bands have similar dynamic moments-of-inertia. Some nuclei exhibit multiple bands, and the backbending phenomenon has been observed. Level spins can be obtained from comparison of transition energies to rotational model formulas. Selected bands (in different nuclei) have equal transition energies (within 0.1%). Alignment in integer multiples of h has been observed. Properties of these bands will be described. C1 RUTGERS STATE UNIV,NEW BRUNSWICK,NJ 08903. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP BECKER, JA (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. RI KORTEN, Wolfram/H-3043-2013; OI KORTEN, Wolfram/0000-0002-3940-0816 NR 27 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 500 EP 503 DI 10.1016/0168-583X(91)96080-5 PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800129 ER PT J AU FEINBERG, B KALNINS, JG KREBS, GF AF FEINBERG, B KALNINS, JG KREBS, GF TI RADIOACTIVE ION-BEAMS AT THE BEVALAC - GREATLY ENHANCED FRAGMENT SEPARATION FOR HIGH-ENERGY BEAMS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID ISOTOPE AB Radioactive beams are routinely produced at the Bevalac by the fragmentation process. High energy beams (energies approximately 800 MeV/u) produce fragments with nearly the original beam momentum, forming a radioactive ion beam. A new beamline is being constructed which will provide resolution for ions approaching the mass 100 region, compared to the present mass 20 capability, by strongly increasing the dispersion and also increasing the beam size for easier tuning and more effective collimation. In addition, the angular acceptance has been more than doubled. Details of the design will be presented. RP FEINBERG, B (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 542 EP 545 DI 10.1016/0168-583X(91)96091-X PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800140 ER PT J AU CORMIER, TM COLE, JD HAMILTON, JH RAMAYYA, AV AF CORMIER, TM COLE, JD HAMILTON, JH RAMAYYA, AV TI A LARGE SOLID ANGLE HIGH-RESOLUTION RECOIL MASS-SPECTROMETER FOR USE WITH RADIOACTIVE BEAMS AT GAMMASPHERE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB A large solid angle, high resolution, recoil mass spectrometer has been designed for use with heavy ion beams from the Holifield Heavy Ion Facility at Oak Ridge National Laboratory. The design has been coordinated with the GAMMASPHERE detector project such that the spectrometer will operate with this 110-element germanium detector array at its target or focal plane positions with minimum loss of gamma ray solid angle. The spectrometer has been designed with the specific intention of using inverse kinematic reactions. The use of inverse kinematics tremendously enhances the capabilities of the spectrometer and selected examples will be discussed including the use of low intensity radioactive beams. C1 IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415. VANDERBILT UNIV,DEPT PHYS,NASHVILLE,TN 37235. RP CORMIER, TM (reprint author), TEXAS A&M UNIV SYST,INST CYCLOTRON,COLLEGE STN,TX 77840, USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 546 EP 549 DI 10.1016/0168-583X(91)96092-Y PN 1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800141 ER PT J AU COWAN, TE HOWELL, RH ROHATGI, RR FAJANS, J AF COWAN, TE HOWELL, RH ROHATGI, RR FAJANS, J TI PROPOSED SEARCH FOR RESONANT STATES IN POSITRON-ELECTRON SCATTERING USING A POSITRON GAS-TARGET SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID BHABHA SCATTERING; MEV ENERGIES; COLLISIONS; U+U AB Narrow correlated positron-electron peaks discovered in superheavy nuclear collisions may be signatures for previously undetected neutral particlelike objects having masses of 1-2 MeV/c2. We have designed an experiment to definitively test this hypothesis by searching for resonant states formed directly in the scattering of monoenergetic electrons incident on a gas of cold positrons confined magnetically in a Maimberg trap. This technique will provide a hundredfold improvement in sensitivity to e+e- resonances compared to previous positron-beam, thin-foil scattering experiments. Together with a recoil-shadow technique, this experiment will explore a five decade range in neutral-particle lifetimes (10(-13) to 10(-8) s) which cannot be probed directly by other methods. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. RP COWAN, TE (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DEPT PHYS,LIVERMORE,CA 94550, USA. RI Cowan, Thomas/A-8713-2011; Fajans, Joel/J-6597-2016 OI Cowan, Thomas/0000-0002-5845-000X; Fajans, Joel/0000-0002-4403-6027 NR 18 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 599 EP 603 DI 10.1016/0168-583X(91)96105-T PN 1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ888 UT WOS:A1991FQ88800154 ER PT J AU ROBERTSON, JD BATES, JB DUDNEY, NJ ZUHR, RA AF ROBERTSON, JD BATES, JB DUDNEY, NJ ZUHR, RA TI ION-BEAM ANALYSIS OF LITHIUM-ION CONDUCTING AMORPHOUS ELECTROLYTE FILMS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID THIN SAMPLES; PIGE AB The Li/Si and Li/P ratios in 1-2-mu-m thick xLi2O:ySiO2:zP2O5 amorphous electrolyte films were determined by proton-induced gamma-ray emission analysis (PIGE) using a 4 MeV proton beam. These measurements were performed with the new IBA facility which has been installed at the University of Kentucky 7.5 MV, Model CN Van de Graaff accelerator. The nondestructive PIGE determination of the Li content of the films played an integral role in understanding this three component system as the PIGE measurements proved to be more reliable than either SIMS or ICP-AE analyses. The conductivity of the films was strongly dependent on the Li2O content; reduction of the Li2O content of the films resulted in large decreases in the mobility of the lithium ions. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP ROBERTSON, JD (reprint author), UNIV KENTUCKY,DEPT CHEM,LEXINGTON,KY 40506, USA. RI Dudney, Nancy/I-6361-2016 OI Dudney, Nancy/0000-0001-7729-6178 NR 13 TC 14 Z9 14 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 722 EP 725 DI 10.1016/0168-583X(91)95012-3 PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000012 ER PT J AU BOZOIAN, M AF BOZOIAN, M TI THRESHOLDS OF NON-RUTHERFORD NUCLEAR CROSS-SECTIONS FOR ION-BEAM ANALYSIS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID ELASTIC-SCATTERING; INELASTIC-SCATTERING; LI-6; POTENTIALS AB A theoretical model of classical scattering in the presence of combined Coulomb and weakly perturbing nuclear fields predicts the incident ion energies at which elastic backscattering cross sections begin to deviate from their Rutherford values [M. Bozoian et al., Nucl. Instr. and Meth. B51 (1990) 311]. The model, parameterized with two nuclear constants, is in good agreement with experimental data for proton and helium-ion beams. This classical model was revised by including the nature of the Z = 1 and 2 projectiles. In this paper the revised model is applied to Z = 3 projectiles. Although little backscattering data exists, there is consistency among the optical model calculations of departures from Rutherford backscattering for the lithium-target systems considered. The revised model is in good agreement with these calculations. New experimental results for Li-6 and Li-7 ion beams compared with the revised model are presented at this conference [K.M. Hubbard et al., Bull. Am. Phys. Soc. 35 (1990) 1785]. RP BOZOIAN, M (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 18 TC 22 Z9 22 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 740 EP 743 DI 10.1016/0168-583X(91)95016-7 PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000016 ER PT J AU HORNADY, RS AF HORNADY, RS TI MATERIALS IMPURITY ANALYSIS BY MEANS OF NUCLEAR-RESONANCE REACTIONS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB An automated beam line for measurement of trace impurities in materials is installed on the FN tandem in the Center for Accelerator Mass Spectrometry, LLNL. The major purpose of the beam-line system is to determine the diffusion of water into glasses by use of the F-19(p, alpha-gamma)O-16 reaction. This study is stimulated by the radiation-waste-isolation program; however, the system is applicable to studies of other impurities in many material matrices. The target wheels, each of which holds twenty-four samples, can be changed in less than an hour. The beam-line control system both indexes the target wheel and controls the tandem energy as it steps through the requested measurement protocol. The tandem control system, in response to a request, adjusts the terminal potential and other transport elements to maintain constant spot size and location. RP HORNADY, RS (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,CTR ACCELERATOR MASS SPECTROMETRY,LIVERMORE,CA 94550, USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 809 EP 811 DI 10.1016/0168-583X(91)95034-B PN 2 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000034 ER PT J AU TUNIZ, C ZANINI, F JONES, KW AF TUNIZ, C ZANINI, F JONES, KW TI PROBING THE ENVIRONMENT WITH ACCELERATOR-BASED TECHNIQUES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID SYNCHROTRON RADIATION; MICROPROBE; SAMPLES AB Natural and anthropogenic events are changing atmosphere, water, soil and other parts of our planet. Advanced analytical techniques based on particle accelerators can provide useful tools to characterize samples of environmental interest. For example, accelerator mass spectrometry (AMS) is used to detect geological tracers and chronometers, such as C-14, Be-10, Cl-36 and I-129, present at ultratrace levels in the environment. These long-lived isotopes are useful for the study of soil erosion and salinization, ground water management and nuclear waste disposal. Another accelerator-based analytical technique, synchrotron-radiation-induced X-ray emission (SRIXE), can be used to study the microscopic distribution of heavy metals and other trace elements in the environment. SRIXE microprobes are being developed to map trace elements in individual micron-size particles and micro-organisms. C1 SINCROTRONE TRIESTE,I-34012 TRIESTE,ITALY. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP TUNIZ, C (reprint author), UNIV TRIESTE,IST NAZL FIS NUCL,DIPARTIMENTO FIS,I-34127 TRIESTE,ITALY. OI Zanini, Franco/0000-0003-0702-1157 NR 21 TC 6 Z9 6 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 877 EP 881 DI 10.1016/0168-583X(91)95051-E PN 2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000051 ER PT J AU ROBERTS, ML SOUTHON, JR DAVIS, JC PROCTOR, ID NELSON, DE AF ROBERTS, ML SOUTHON, JR DAVIS, JC PROCTOR, ID NELSON, DE TI A DEDICATED AMS FACILITY FOR H-3 AND C-14 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID ACCELERATOR AB Accelerator mass spectrometry is a high sensitivity technique for the detection of numerous long-lived radionuclides at extremely low concentrations. The present use of this measurement tool is primarily in archeology and the geosciences. However, novel applications and technological advancements that can have a significant impact on biomedical research, clinical procedures and environmental investigations have been identified. We are designing and are in the process of testing two small spectrometer concepts. One spectrometer is optimized to measure only hydrogen isotopes, while the second concept is designed to measure both carbon and hydrogen isotopes simultaneously. C1 SIMON FRASER UNIV,DEPT ARCHAEOL,BURNABY V5A 1S6,BC,CANADA. RP ROBERTS, ML (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,CTR ACCELERATOR MASS SPECTROMETRY,LIVERMORE,CA 94550, USA. NR 7 TC 7 Z9 7 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 882 EP 885 DI 10.1016/0168-583X(91)95052-F PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000052 ER PT J AU WEINLEIN, JH ONEAL, ML BACON, FM AF WEINLEIN, JH ONEAL, ML BACON, FM TI A PULSED NEUTRON GENERATOR FOR INVIVO BODY-COMPOSITION STUDIES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB A neutron generator system utilizing two Zetatron neutron tubes has been designed and delivered to the U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University for use in clinical measurements of body carbon by neutron inelastic scattering. Each neutron tube is capable of delivering 10(3) - 10(4) 14-MeV neutrons in a 7-mu-s pulse at repetition rates of 4 or 8 kHz, and can be operated independently as well as in a master-slave mode. The neutron tubes are gas filled with a mixture of deuterium and tritium; the target of the tube is operated at -30 to -60 kV dc and the ion source is operated with a 2.5-kV, 7-mu-s pulse. The tube gas pressure is monitored and controlled by measuring the total current in the high voltage circuit and feeding it back to the gas-reservoir drive circuit. Neutrons were measured with a plastic scintillator and photomultiplier tube. RP WEINLEIN, JH (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 8 TC 9 Z9 9 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 904 EP 906 DI 10.1016/0168-583X(91)95058-L PN 2 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000058 ER PT J AU ALVERSON, G AYER, F BHANOT, G DAUTAT, H DUNN, WL DYE, S ELDER, C FAISSLER, W GLAUBMAN, M VONGOELER, E GRIMES, A HECHT, M HOFTEIZER, J HURLBUT, C JAQUET, P JONES, G KAMON, T KLEIN, S LANE, C LEEDOM, I MCINTYRE, RJ MILLER, JP MOROMISATO, J MUCCI, J MURRAY, J MYERS, SK OFOGHLUNDHA, F OH, C ORR, D PERLMAN, D POTHIER, E RAHMAN, MA REARDON, J REUCROFT, S ROBERTS, BL SALETAN, E SAUPP, SL SCHULTE, T SIMPKINS, JD STAPLETON, JW STONE, J SULAK, L SULLIVAN, D THURSTON, T WEBB, R WINN, D WOMBLE, E WOOSLEY, JK WORSTELL, W YACOUT, AM AF ALVERSON, G AYER, F BHANOT, G DAUTAT, H DUNN, WL DYE, S ELDER, C FAISSLER, W GLAUBMAN, M VONGOELER, E GRIMES, A HECHT, M HOFTEIZER, J HURLBUT, C JAQUET, P JONES, G KAMON, T KLEIN, S LANE, C LEEDOM, I MCINTYRE, RJ MILLER, JP MOROMISATO, J MUCCI, J MURRAY, J MYERS, SK OFOGHLUNDHA, F OH, C ORR, D PERLMAN, D POTHIER, E RAHMAN, MA REARDON, J REUCROFT, S ROBERTS, BL SALETAN, E SAUPP, SL SCHULTE, T SIMPKINS, JD STAPLETON, JW STONE, J SULAK, L SULLIVAN, D THURSTON, T WEBB, R WINN, D WOMBLE, E WOOSLEY, JK WORSTELL, W YACOUT, AM TI TEXAS - A CALORIMETER-BASED HIGH-RATE DETECTOR FOR THE SSC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB The conceptual design for a novel SSC detector that focuses on calorimetry is presented. The physics goals include searches for elementary scalars of low mass (M(H) < 2 M(W)) and high mass (M(H) > 600 GeV), for heavy supersymmetric matter, for compositeness and for strong vector-boson interactions. Examples of the relevant signatures are H --> gamma-gamma; H --> ZZ*; H --> l-nu-qqBAR, ll-nu-nu, llqqBAR; g-approximately g-approximately --> E(T)miss + > 2 jets; and a jet excess at high p(T). These goals may be achieved with high precision, fast, compensated and truly hermetic calorimetry, optimized for electrons, photons, and jets. The design allows for total hermeticity to eta = 5.5 missing energy. All the goals require operation at high luminosity and the additional concerns of gamma-gamma and jet-jet separation, as well as survival in a high radiation environment, are addressed by an unusually large inner radius of the detector. The detector concept consists of the following few and well defined components: a scintillating fiber tracking system incorporating an imaging preradiator, a projective, finely segmented, thick scintillator calorimeter; and a muon TRD trigger and spectrometer. C1 BOSTON UNIV,BOSTON,MA 02215. DREXEL UNIV,PHILADELPHIA,PA 19104. FAIRFIELD UNIV,FAIRFIELD,CT 06430. TEXAS A&M UNIV SYST,COLLEGE STN,TX 77843. BICRON CORP,NEWBURY,OH. CHARLES STARK DRAPER LAB INC,CAMBRIDGE,MA 02139. HAMAMATSU CORP,MIDDLESEX,NJ 08846. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RCA CORP,GE,CAMDEN,NJ 08102. TELEDYNE BROWN ENGN INC,HUNTSVILLE,AL 35807. THINKING MACHINES CORP,CAMBRIDGE,MA. RP ALVERSON, G (reprint author), NORTHEASTERN UNIV,BOSTON,MA 02115, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 948 EP 951 DI 10.1016/0168-583X(91)95068-O PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000068 ER PT J AU YOUNG, LM AF YOUNG, LM TI COMPACT PHOTOINJECTOR ACCELERATORS FOR FREE-ELECTRON LASERS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID ALAMOS AB A compact photoinjector accelerator has been built for the Los Alamos free electron laser facility. This accelerator produces a very high quality beam at 6 MeV with a peak current of 300 A and an emittance < 50-pi-mm mrad. Two more compact photoinjector accelerators now being designed and built will incorporate features to eliminate certain problems that affected the first photoinjector accelerator. One problem, multipacting in the coupling cells, has been solved in the 6-MeV accelerator. Another problem, observed in this accelerator, is a small quadrupole component in the accelerating field, which is caused by the coupling slots. The new design will reduce this effect. This phenomenon was detectable only because the beam quality was excellent. RP YOUNG, LM (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 978 EP 981 DI 10.1016/0168-583X(91)95076-P PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000076 ER PT J AU JAMESON, RA AF JAMESON, RA TI ACCELERATOR-DRIVEN NEUTRON SOURCES FOR MATERIALS RESEARCH SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB Particle accelerators are important tools for materials research and production. Advances in high-intensity linear accelerator technology make it possible to consider enhanced neutron sources for fusion material studies (e.g. using the D-Li reaction) or as a source of spallation neutrons. Energy variability, uniformity of target dose distribution, target bombardment from multiple directions, time-scheduled dose patterns, and other features can be provided, opening new experimental opportunities. New designs have also been used to ensure hands-on maintenance on the accelerator in these factory-type facilities. Designs suitable for proposals such as the Japanese Energy-Selective Intense Neutron Source (ESNIT) (20-40 mA cw deuteron beam), and the International Fusion Materials Irradiation Facility (IFMIF) (250 mA cw deuteron beam modules) are discussed. RP JAMESON, RA (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV ACCELERATOR TECHNOL,MS H811,LOS ALAMOS,NM 87545, USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 982 EP 986 DI 10.1016/0168-583X(91)95077-Q PN 2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000077 ER PT J AU MCKENZIEWILSON, RB AF MCKENZIEWILSON, RB TI THE NEUTRAL BEAM TEST FACILITY AND RADIATION EFFECTS FACILITY AT BROOKHAVEN-NATIONAL-LABORATORY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB As part of the Strategic Defense Initiative (SDI) Brookhaven National Laboratory (BNL) has constructed a Neutral Beam Test Facility (NBTF) and a Radiation Effects Facility (REF). These two facilities use the surplus capacity of the 200-MeV linac injector for the Alternating Gradient Synchrotron (AGS). The REF can be used to simulate radiation damage effects in space from both natural and man-made radiation sources. The H- beam energy, current and dimensions can be varied over a wide range leading to a broad field of applications. The NBTF has been designed to carry out high precision experiments and contains an absolute reference target system for the on-line calibration of measurements carried out in the experimental hall. The H- beam energy, current and dimensions can also be varied over a wide range but with tradeoffs depending on the required accuracy. Both facilities are fully operational and will be described together with details of the associated experimental programs. RP MCKENZIEWILSON, RB (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 987 EP 990 PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000078 ER PT J AU LAWRENCE, GP AF LAWRENCE, GP TI HIGH-POWER LINEAR ACCELERATORS FOR TRITIUM PRODUCTION AND TRANSMUTATION OF NUCLEAR WASTE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB Proton linacs driving high-flux spallation neutron sources are being considered for transmutation of nuclear waste and production of tritium. Advances in high-current linac technology have provided a basis for the development of credible designs for the required accelerator, which has a nominal 1.6-GeV energy, and a 250-mA cw current. A beam with these parameters incident on a lead or lead-bismuth (Pb-Bi) spallation target generates high fluxes of thermal neutrons which can be used in a surrounding blanket to produce tritium through the Li-6(n, alpha)T or He-3(n, p)T reactions, or to burn long-lived actinides and fission products in nuclear waste through capture and fission processes. In some scenarios waste actinides and/or other fissile materials in the blanket can produce sufficient fission energy to power the accelerator. RP LAWRENCE, GP (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV ACCELERATOR TECHNOL,LOS ALAMOS,NM 87545, USA. NR 9 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1000 EP 1004 DI 10.1016/0168-583X(91)95081-N PN 2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000081 ER PT J AU RHOADESBROWN, MJ AF RHOADESBROWN, MJ TI STRONG FIELD EFFECTS AND THE LUMINOSITY LIFETIME OF A HEAVY-ION COLLIDER SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB The Relativistic Heavy Ion Collider (RHIC) will accelerate fully stripped ions to beam kinetic energies of 250 (Z/A) GeV/u. For the heaviest nuclei, i.e., 179Au79+, 10(9) ions per bunch will circulate in 57 bunches at a kinetic energy of 100 GeV/u. During bunch crossing, the peripheral interactions of the heavy ions generate a sufficiently large electromagnetic field that spontaneous e+, e- pair creations will occur. Up to 10(7) pairs per second are expected at RHIC luminosity values (2 x 10(26) cm-2 s-1). In addition, a produced electron may be captured by a heavy ion, thus strongly effecting the luminosity lifetime of a heavy ion collider. RP RHOADESBROWN, MJ (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1017 EP 1020 DI 10.1016/0168-583X(91)95085-R PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000085 ER PT J AU DELAYEN, JR BOHN, CL ROCHE, CT AF DELAYEN, JR BOHN, CL ROCHE, CT TI APPLICATION OF RF SUPERCONDUCTIVITY TO HIGH-BRIGHTNESS ION-BEAM ACCELERATORS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID HIGH-TC SUPERCONDUCTORS; SURFACE-RESISTANCE AB A development program is underway to apply rf superconductivity to the design of cw linear accelerators for high-brightness ion beams. The key issues associated with this endeavor have been delineated in an earlier paper. Considerable progress has been made both experimentally and theoretically to resolve a number of these issues. In this paper we summarize this progress. We also identify current and future work in the areas of accelerator technology and superconducting materials which will confront the remaining issues and/or provide added capability to the technology. RP DELAYEN, JR (reprint author), ARGONNE NATL LAB,DIV ENGN PHYS,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1025 EP 1028 DI 10.1016/0168-583X(91)95087-T PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000087 ER PT J AU BERNO, A VOGEL, JS CAFFEE, M AF BERNO, A VOGEL, JS CAFFEE, M TI HIGH-SPEED ACQUISITION OF MULTIPARAMETER DATA USING A MACINTOSH-IICX SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB Accelerator mass spectrometry systems based on > 3 MV tandem accelerators often use multianode ionization detectors and/or time-of-flight detectors to identify individual isotopes through multiparameter analysis. A Macintosh IIcx has been programmed to collect AMS data from a CAMAC-implemented analyzer and to display the histogrammed individual parameters and a double-parameter array. The computer-CAMAC connection is through a NuBus to CAMAC dataway interface which allows direct addressing to all functions and registers in the crate. Asynchronous data from the rare isotope are sorted into a CAMAC memory module by a list sequence controller. Isotope switching is controlled by a one-cycle timing generator. A rate-dependent amount of time is used to transfer the data from the memory module at the end of each timing cycle. The present configuration uses 10-75 ms for rates of 500-10 000 cps. Parameter analysis occurs during the rest of the 520 ms data collection cycle. Completed measurements of the isotope concentrations of each sample are written to files which are compatible with standard Macintosh databases or other processing programs. The system is inexpensive and operates at speeds comparable to those obtainable using larger computers. RP BERNO, A (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,CTR ACCELERATOR MASS SPECTROMETRY,LIVERMORE,CA 94550, USA. RI Caffee, Marc/K-7025-2015 OI Caffee, Marc/0000-0002-6846-8967 NR 6 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1076 EP 1079 DI 10.1016/0168-583X(91)95100-R PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000100 ER PT J AU ROBERTS, ML MOORE, TL AF ROBERTS, ML MOORE, TL TI SUCCESS WITH AN AUTOMATED COMPUTER CONTROL-SYSTEM SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB LLNL has successfully implemented a distributed computer control system for automated operation of an FN tandem accelerator. The control system software utilized is the Thaumaturgic Automated Control Logic (TACL) written by the Continuous Electron Beam Accelerator Facility and co-developed with LLNL. Using TACL, accelerator components are controlled through CAMAC using a two-tiered structure. Analog control and measurement are at 12 or 16 bit precision as appropriate. Automated operation has been implemented for several nuclear analytical techniques including hydrogen depth profiling and accelerator mass spectrometry. An additional advantage of TACL lies in its expansion capabilities. Without disturbing existing control definitions and algorithms, additional control algorithms and display functions can be implemented quickly. RP ROBERTS, ML (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,CTR ACCELERATOR MASS SPECTROMETRY,LIVERMORE,CA 94550, USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1080 EP 1083 DI 10.1016/0168-583X(91)95101-I PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000101 ER PT J AU SAADATMAND, K SCHNEIDER, JD GEISIK, C STEVENS, RR AF SAADATMAND, K SCHNEIDER, JD GEISIK, C STEVENS, RR TI BEAM STRUCTURE STUDIES OF LOW-ENERGY ION-BEAMS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB The ion beam structure at various axial positions along the beam-transport line has been monitored and studied utilizing a fluor screen and a video camera. The fluor material is aluminum oxide that is plasma-jet sprayed onto the surface of an aluminum or a water-cooled copper substrate. The visual representation of the beam structure is digitized and enhanced through use of false-color coding and displayed on a TV monitor for the on-line viewing by the experimentalist. Digitized video signals are stored for further off-line processing and extracting more information about the beam, such as beam profiles. This inexpensive and effective diagnostic enables the experimentalist to observe the real-time beam response (such as evolution of the beam structure, shifts in the beam intensity at various spatial locations within the beam perimeter, and shifts in the beam center and position) to parameter changes. C1 UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. NR 2 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1088 EP 1090 DI 10.1016/0168-583X(91)95103-K PN 2 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000103 ER PT J AU BLIND, B AF BLIND, B TI PRODUCTION OF UNIFORM AND WELL-CONFINED BEAMS BY NONLINEAR OPTICS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB Particle beams with uniform and well-confined intensity distributions are desirable for medical treatment, food irradiation, and ion implantation, and are essential in high-intensity accelerator systems to prevent target damage and optimize target efficiency. One method for beam redistribution employs nonlinear beamline elements of odd multipolarity, such as octupoles and duodecapoles. The method is not limited to the production of uniform beam distributions. Techniques for producing uniform and well-confined beam distributions are reviewed. Beam redistribution is explained and the degree of uniformity and confinement achievable under various conditions is discussed. A method for tuning the size of the irradiation area is given. An unconventional combined-function magnet is presented. The effect of beam jitter on distributions is considered. Applications of the method are given. RP BLIND, B (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV ACCELERATOR TECHNOL,LOS ALAMOS,NM 87545, USA. NR 12 TC 16 Z9 16 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1099 EP 1102 DI 10.1016/0168-583X(91)95106-N PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000106 ER PT J AU MOSKO, SW AF MOSKO, SW TI THE DESIGN OF THE RF CAVITY FOR THE HEAVY-ION STORAGE RING FOR ATOMIC PHYSICS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB An rf cavity and drive system have been designed for the proposed heavy ion storage ring for atomic physics (HISTRAP) at Oak Ridge. A peak accelerating voltage of 2.5 kV per turn is required with a continuous tuning range from 200 kHz through 2.7 MHz. A single-gap, half-wave resonant configuration is used with biased ferrite tuning. The cavity structure is completely outside of the beam line/vacuum enclosure except for a single rf window that serves as an acclerating gap. Physical separation of the cavity and beam line permits in situ vacuum baking of the beam line components at 300-degrees-C. A prototype cavity was designed, built, and tested [S.W. Mosko et al., Proc. 1989 IEEE Particle Accelerator Conf., p. 193]. Development of frequency synthesizer and tuner control circuitry is under way. RP MOSKO, SW (reprint author), OAK RIDGE NATL LAB,POB 2008,OAK RIDGE,TN 37831, USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1119 EP 1123 DI 10.1016/0168-583X(91)95111-P PN 2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000111 ER PT J AU BERRY, LA GORBATKIN, SM AF BERRY, LA GORBATKIN, SM TI ELECTRON-CYCLOTRON RESONANCE MICROWAVE ION SOURCES FOR THIN-FILM PROCESSING SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID CHEMICAL VAPOR-DEPOSITION; PLASMA SYSTEM; ECR PLASMA; DISCHARGES; SILICON; TECHNOLOGY; EPITAXY; STREAM AB Plasmas created by microwave absorption at the electron cyclotron resonance (ECR) are increasingly used for a variety of plasma processes, including both etching and deposition. ECR sources efficiently couple energy to electrons and use magnetic confinement to maximize the probability of an electron creating an ion or free radical in pressure regimes where the mean free path for ionization is comparable to the ECR source dimensions. The general operating principles of ECR sources are discussed with special emphasis on their use for thin film etching. Data on source performance during Cl based etching of Si using an ECR system are presented. RP BERRY, LA (reprint author), OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. NR 33 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1133 EP 1137 DI 10.1016/0168-583X(91)95114-S PN 2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000114 ER PT J AU BEIERSDORFER, P AF BEIERSDORFER, P TI PHYSICS OF AND RECENT RESULTS FROM THE LAWRENCE-LIVERMORE EBIT SOURCE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID HIGHLY CHARGED IONS; ELECTRON-BEAM; DIELECTRONIC-RECOMBINATION; CROSS-SECTIONS; EXCITATION; TRAP AB The electron beam ion trap at Lawrence Livermore National Laboratory is used to produce and trap very highly charged ions for the study of electron-ion interactions. Measurements of X-ray transitions in neonlike thorium (Th80+), ionization cross sections of lithiumlike barium (Ba53+), and of level-specific dielectronic recombination cross sections of helium-like ion (Fe24+) are presented. RP BEIERSDORFER, P (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DIV HIGH TEMP PHYS,POB 808,LIVERMORE,CA 94550, USA. NR 24 TC 24 Z9 24 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1144 EP 1147 DI 10.1016/0168-583X(91)95117-V PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000117 ER PT J AU TSAI, CC AF TSAI, CC TI POTENTIAL APPLICATIONS OF A NEW MICROWAVE ECR MULTICUSP PLASMA ION-SOURCE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB A new microwave electron cyclotron resonance (ECR) multicusp plasma ion source using two ECR plasma production regions and multicusp plasma confinement has been developed at Oak Ridge National Laboratory. This source has been operated to produce uniform and dense plasmas over large areas of 300-400 cm2. The plasma source has been operated with continuous argon gas feed and pulsed microwave power. The discharge initiation phenomena and plasma properties have been investigated and studied as functions of discharge parameters. Together with the discharge characteristics observed, a hypothetical discharge mechanism for this plasma source is reported and discussed. Potential applications, including plasma and ion-beam processing for manufacturing advanced microelectronics and for space electric propulsion, are discussed. RP TSAI, CC (reprint author), OAK RIDGE NATL LAB,DIV FUS ENERGY,OAK RIDGE,TN 37831, USA. NR 7 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1166 EP 1170 DI 10.1016/0168-583X(91)95122-T PN 2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000122 ER PT J AU LENNOX, AJ AF LENNOX, AJ TI HOSPITAL-BASED PROTON LINEAR-ACCELERATOR FOR PARTICLE THERAPY AND RADIOISOTOPE PRODUCTION SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX AB Taking advantage of recent advances in linear accelerator technology, it is possible for a hospital to use a 70 MeV proton linac for fast neutron therapy, boron neutron capture therapy, proton therapy for ocular melanomas, and production of radiopharmaceuticals. The linac can also inject protons into a synchrotron for proton therapy of deep-seated tumors. With 180-mu-A average current, a single linac can support all these applications. This paper presents a conceptual design for a medical proton linac, switchyard, treatment rooms, and isotope production rooms. Special requirements for each application are outlined and a layout for sharing beam among the applications is suggested. C1 RUSH UNIV,CHICAGO,IL 60612. RP LENNOX, AJ (reprint author), FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. NR 9 TC 6 Z9 6 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1197 EP 1200 DI 10.1016/0168-583X(91)95130-6 PN 2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000130 ER PT J AU DILMANIAN, FA GARRETT, RF THOMLINSON, WC BERMAN, LE CHAPMAN, LD HASTINGS, JB LUKE, PN OVERSLUIZEN, T SIDDONS, DP SLATKIN, DN STOJANOFF, V THOMPSON, AC VOLKOW, ND ZEMAN, HD AF DILMANIAN, FA GARRETT, RF THOMLINSON, WC BERMAN, LE CHAPMAN, LD HASTINGS, JB LUKE, PN OVERSLUIZEN, T SIDDONS, DP SLATKIN, DN STOJANOFF, V THOMPSON, AC VOLKOW, ND ZEMAN, HD TI COMPUTED-TOMOGRAPHY WITH MONOCHROMATIC X-RAYS FROM THE NATIONAL-SYNCHROTRON-LIGHT-SOURCE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID CORONARY ANGIOGRAPHY; BLOOD-FLOW; RADIATION; SYSTEM; BRAIN; BEAM; DETECTORS; CAMERA AB A multiple-energy computed tomography (MECT) system that employs monochromatic and tunable 33-100 keV X rays from a superconducting wiggler at the National Synchrotron Light Source is being developed at Brookhaven National Laboratory. The CT configuration is that of a fixed, horizontal fan-shape beam and a subject seated in a rotating chair. Two quantitative CT methods will be used: a) K-edge subtraction of intravenously administered iodine (or a heavier element) to image brain tumors, large blood vessels of the lower head and neck, and arteriovenous malformations; and b) dual photon absorptiometry to obtain two brain CT images that map the low-Z elements and the intermediate-Z elements (i.e. P, S, Cl, K, Ca, and Fe) separately. The system is expected to provide 0.5 mm spatial resolution, horizontally, with unprecedented image contrast and accuracy of quantification. The system will employ a two-crystal monochromator and a high-purity Ge linear array detector. C1 BROOKHAVEN NATL LAB,NATZ SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV SAO PAULO,INST PHYS,SAO PAULO,BRAZIL. RP DILMANIAN, FA (reprint author), BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973, USA. RI stojanoff, vivian /I-7290-2012; Chapman, Dean/I-6168-2013 OI stojanoff, vivian /0000-0002-6650-512X; Chapman, Dean/0000-0001-6590-4156 NR 33 TC 29 Z9 29 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1208 EP 1213 DI 10.1016/0168-583X(91)95133-X PN 2 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000133 ER PT J AU ZEMAN, HD DILMANIAN, FA GARRETT, RF BERMAN, LE CHAPMAN, LD HASTINGS, JB OVERSLUIZEN, T SIDDONS, DP STOJANOFF, V THOMLINSON, WC AF ZEMAN, HD DILMANIAN, FA GARRETT, RF BERMAN, LE CHAPMAN, LD HASTINGS, JB OVERSLUIZEN, T SIDDONS, DP STOJANOFF, V THOMLINSON, WC TI AN X-RAY MONOCHROMATOR FOR DUAL-ENERGY COMPUTERIZED-TOMOGRAPHY USING SYNCHROTRON RADIATION SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID ANGIOGRAPHY; DETECTOR AB Dual-energy CT imaging of the brain will be performed using synchrotron radiation X-ray beams at about 40 and 80 keV to visualize the altered concentrations of the intermediate-Z elements that occur in brain lesions and atherosclerotic plaques. The monochromator designs considered allow rapid switching between these two energies without change in the position or direction of the X-ray beam. One design uses the fundamental and second harmonic radiations from an existing dual-Bragg-crystal Si<2,2,0> monochromator. In this design the 40 and 80 keV beams would be isolated by monochromator detuning or gold filtration, respectively. The other designs utilize fundamental radiations for both energies and would require some modification of the existing monochromator mechanism to achieve adequate tuning speed. These designs use two Si<2,2,0> crystals, one with a Bragg and the other with either a Bragg or a Laue geometry. C1 BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973. BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973. RP ZEMAN, HD (reprint author), UNIV TENNESSEE,CTR HLTH SCI,DEPT BIOMED ENGN,MEMPHIS,TN 38163, USA. RI stojanoff, vivian /I-7290-2012; Chapman, Dean/I-6168-2013 OI stojanoff, vivian /0000-0002-6650-512X; Chapman, Dean/0000-0001-6590-4156 NR 14 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1218 EP 1222 DI 10.1016/0168-583X(91)95135-Z PN 2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000135 ER PT J AU THIEBERGER, P STASSINOPOULOS, EG VANGUNTEN, O ZAJIC, V AF THIEBERGER, P STASSINOPOULOS, EG VANGUNTEN, O ZAJIC, V TI HEAVY-ION BEAMS FOR SINGLE-EVENT RESEARCH AT BROOKHAVEN - PRESENT AND FUTURE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11TH INTERNATIONAL CONF ON THE APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY CY NOV 05-08, 1990 CL DENTON, TX ID FACILITY AB Since low energy nuclear physics research was discontinued at Brookhaven and replaced by a relativistic heavy ion program, large blocks of time became available at the tandem Van de Graaff facility for technological applications and for research in other areas. The main technological application has been the single event upset (SEU) testing of microelectronic devices, and this activity has been steadily increasing over the last few years. The ion beam requirements for this type of work are discussed and a description is given of methods used for satisfying these requirements at the Brookhaven facility. Available ion species, energies, ranges, LETs and beam intensities, purity and uniformity are discussed. Characteristics are summarized of a sophisticated and extremely user friendly test chamber and associated hardware and software installed at Brookhaven by a coalition of government agencies and made available for general use. The possibility is mentioned of extending SEU testing to higher energies by using heavy ion beams from a booster synchrotron now under construction and from the existing large alternating gradient synchrotron (AGS). Finally a brief discussion is given of compatibility with other programs and of future availability of low and high energy heavy ions for SEU testing at Brookhaven. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. LAB PHYS SCI,COLLEGE PK,MD. RP THIEBERGER, P (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 13 TC 6 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1991 VL 56-7 BP 1251 EP 1255 DI 10.1016/0168-583X(91)95144-3 PN 2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FQ890 UT WOS:A1991FQ89000144 ER PT J AU DRUMM, CR FAN, WC RENKEN, JH AF DRUMM, CR FAN, WC RENKEN, JH TI FORWARD AND ADJOINT METHODS AND APPLICATIONS FOR DETERMINISTIC ELECTRON-PHOTON TRANSPORT SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID OPERATOR AB The ability to efficiently model coupled electron-photon transport is essential for determining the response of electronics components to nuclear radiation environments. Furthermore, to fully characterize the effect of many different radiation environments on a component, an adjoint transport capability is desirable. The theory of adjoint electron-photon transport is described with the CEPXS/ONEDANT-LD discrete ordinates code package and the method is applied to a set of example problems representative of those encountered in radiation effects testing. Adjoint transport, in addition to efficiently modeling radiation source variations, can effectively model geometry variations for certain classes of problems. A new linear-discontinuous approximation of the continuous slowing down operator that introduces no upscatter is also developed. RP DRUMM, CR (reprint author), SANDIA NATL LABS,DEPT RADIAT EFFECTS,ALBUQUERQUE,NM 87185, USA. NR 23 TC 4 Z9 4 U1 0 U2 2 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD MAY PY 1991 VL 108 IS 1 BP 16 EP 49 PG 34 WC Nuclear Science & Technology SC Nuclear Science & Technology GA FL046 UT WOS:A1991FL04600002 ER PT J AU WALSH, RL CHIRCU, G MADLAND, DG AF WALSH, RL CHIRCU, G MADLAND, DG TI CALCULATION OF FISSION NEUTRON-SPECTRA FOR SPONTANEOUS FISSION OF PU-240, PU-238 AND PU-242 SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID CF-252 AB The fission neutron spectra for spontaneous fission of Pu-240, Pu-238 and Pu-242 are calculated using the spin-dependent Madland-Nix model. Experimental data on fission neutron spectra for these nuclei are scarce. The calculated differences in the three spectra are presented and compared with the available data, and some repercussions for plutonium assay work are discussed. C1 UNIV NEW S WALES,KENSINGTON,NSW 2033,AUSTRALIA. UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP WALSH, RL (reprint author), AUSTRALIAN NUCL SCI & TECHNOL ORG,LUCAS HTS RES LABS,PRIVATE MAILBAG 1,MENAI,NSW 2234,AUSTRALIA. NR 29 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 SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD MAY PY 1991 VL 108 IS 1 BP 109 EP 115 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA FL046 UT WOS:A1991FL04600007 ER PT J AU DATTOLI, G TORRE, A FANG, H GALLARDO, JC RICHETTA, M AF DATTOLI, G TORRE, A FANG, H GALLARDO, JC RICHETTA, M TI THE 3-D FEL PULSE-PROPAGATION EQUATION - AN ANALYTICAL TREATMENT IN THE LOW-GAIN AND SMALL-SIGNAL REGIME SO NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA D-CONDENSED MATTER ATOMIC MOLECULAR AND CHEMICAL PHYSICS FLUIDS PLASMAS BIOPHYSICS LA English DT Article ID FREE-ELECTRON LASER; ALGEBRAIC VIEW AB In this paper we show that the transverse mode evolution of a FEL operating with short pulses can be treated, in the small-signal and low-gain regime, using a relatively simple mathematical technique leading to a potentially fast numerical algorithm. We also point out that analytical solutions can be obtained for the cases where the slippage length is small compared to the longitudinal bunch length. C1 INST OPT & FINE MECH,SHANGHAI,PEOPLES R CHINA. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP DATTOLI, G (reprint author), ENERGIA NUCL ENERGIA ALTERNAT,CTR RIC ENERGIA FRASCATI,DIP TIB,US FIS APPL,CP 65,I-00044 FRASCATI,ITALY. RI RICHETTA, MARIA/I-8513-2012; OI Gallardo, Juan C/0000-0002-5191-3067 NR 24 TC 1 Z9 1 U1 0 U2 1 PU EDITRICE COMPOSITORI BOLOGNA PI BOLOGNA PA VIA STALINGRADO 97/2, I-40128 BOLOGNA, ITALY SN 0392-6737 J9 NUOVO CIMENTO D JI Nuovo Cimento Soc. Ital. Fis. D-Condens. Matter At. Mol. Chem. Phys. Fluids Plasmas Biophys. PD MAY PY 1991 VL 13 IS 5 BP 615 EP 632 DI 10.1007/BF02451286 PG 18 WC Physics, Multidisciplinary SC Physics GA FN992 UT WOS:A1991FN99200005 ER PT J AU SWEATT, WC MILLER, PA AF SWEATT, WC MILLER, PA TI REFRACTIVE ANALOG FOR MODELING ELECTROSTATIC ION LENSES SO OPTICAL ENGINEERING LA English DT Article DE ELECTROSTATIC LENSES; REAL-RAY TRACING; ION IMAGING; IMAGE ABERRATION; IMAGE DISTORTION; REFRACTIVE ANALOG; ION-PROJECTION LITHOGRAPHY AB Electrostatic lenses are used extensively to control charged-particle beams. In a particular application to ion beam lithography for microelectronics fabrication, it was necessary to perform extensive calculations of the focal properties of cylindrically symmetric ion lenses. We have found that the imaging properties of cylindrical electrostatic ion lenses can be modeled accurately and efficiently by a series of refractive optical lenses. This is a key step toward the use of mature optical design tools for the design of systems that focus charged particles. RP SWEATT, WC (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SOC PHOTO-OPT INSTRUM ENG PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD MAY PY 1991 VL 30 IS 5 BP 615 EP 621 DI 10.1117/12.55839 PG 7 WC Optics SC Optics GA FK496 UT WOS:A1991FK49600015 ER PT J AU HADLEY, GR AF HADLEY, GR TI TRANSPARENT BOUNDARY-CONDITION FOR BEAM PROPAGATION SO OPTICS LETTERS LA English DT Article AB A new boundary condition algorithm is presented that passes outgoing radiation freely with a minimum reflection coefficient (typically 10(-5)) while inhibiting the flux of incoming radiation. In contrast to the commonly used absorber method, this algorithm contains no adjustable parameters and is thus problem independent. It adapts naturally to a standard Crank-Nicholson difference scheme and is shown to be accurate and robust for both two- and three-dimensional problems. RP HADLEY, GR (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 6 TC 242 Z9 253 U1 2 U2 8 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAY 1 PY 1991 VL 16 IS 9 BP 624 EP 626 DI 10.1364/OL.16.000624 PG 3 WC Optics SC Optics GA FH882 UT WOS:A1991FH88200002 PM 19774018 ER PT J AU RATHKE, JW KLINGLER, RJ KRAUSE, TR AF RATHKE, JW KLINGLER, RJ KRAUSE, TR TI PROPYLENE HYDROFORMYLATION IN SUPERCRITICAL CARBON-DIOXIDE SO ORGANOMETALLICS LA English DT Article ID QUADRUPOLAR NUCLEI; MECHANISM; CO2(CO)8; ACTIVATION; HYDROGEN; SOLVENTS; DETECTOR; NMR AB The cobalt carbonyl catalyzed hydroformylation of propylene and related equilibrium and dynamic processes were investigated by means of high-pressure NMR spectroscopy with supercritical carbon dioxide (d = 0.5 g/mL) used as the reaction medium to avoid gas/liquid mixing problems associated with conventional solvents. At 80-degrees-C, the hydroformylation proceeds cleanly in CO2, giving a somewhat improved yield of linear to branched butyraldehyde products, 88%, without use of stirring. The rate of propylene hydroformylation and in situ measurements of the steady-state concentrations of catalytic intermediates [RC(O)Co(CO)4, HCo(CO)4, and Co2(CO)8] were found to be comparable to values for other linear-terminal olefins in nonpolar liquid media. For the hydrogenation of Co2(CO)8 (to form HCo(CO)4) at 80-degrees-C in CO2, the equilibrium constant, Kp = 8.8 x 10(-4) M atm-1, and the rate constants for the forward and reverse reactions (1.6 x 10(-6) atm-1 s-1 and 1.8 x 10(-3) M-1 s-1, respectively) compared closely with values for liquid methylcyclohexane solutions. Potential dynamic processes involving Co2(CO)8, Co4(CO)12, or HCo(CO)4 were explored at temperatures up to 205-degrees-C at 338 atm by means of Co-59, C-13, and H-1 NMR spectroscopy. Due to the low viscosity of the supercritical medium, linewidths for the Co-59 nucleus were decreased by a factor of about 6 compared to values in normal liquids. An NMR pressure-probe design that uses an efficient toroid detector is also described. RP RATHKE, JW (reprint author), ARGONNE NATL LAB,DIV CHEM TECHNOL,ARGONNE,IL 60439, USA. NR 32 TC 176 Z9 177 U1 1 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD MAY PY 1991 VL 10 IS 5 BP 1350 EP 1355 DI 10.1021/om00051a027 PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA FM146 UT WOS:A1991FM14600027 ER PT J AU YOO, MH LEE, JK AF YOO, MH LEE, JK TI DEFORMATION TWINNING IN HCP METALS AND ALLOYS SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article; Proceedings Paper CT ADRIATICO RESEARCH CONF ON DEFECTS IN HEXAGONAL-CLOSE-PACKED METALS CY AUG 14-17, 1990 CL INT CTR THEORET PHYS, TRIESTE, ITALY SP INT CTR THEORET PHYS, COMMISS EUROPEAN COMMUNITIES HO INT CTR THEORET PHYS ID CLOSE-PACKED METALS; COMPUTER-SIMULATION; SINGLE-CRYSTALS; TITANIUM; SLIP; ACCOMMODATION; TEMPERATURES; DISLOCATION; POTENTIALS; BOUNDARIES AB The important role of deformation twinning in plastic deformation of h.c.p. metals and alloys is emphasized and the twin nucleation mechanisms are examined. A bifurcated homogeneous nucleation model is presented on the basis of the classical nucleation theory, the shape bifurcation theory and the elastic inclusion model. The activation energy for twin formation depends most sensitively on the twin-boundary energy. The structures and energies of (112BAR2) and (101BAR1) coherent twin boundaries are obtained by atomistic simulations using the Lennard-Jones potential for a model h.c.p. metal. The anisotropic coupling effect of normal stresses on twin dislocation mobility is determined over a wide temperature range (0-1200 K). The available experimental data on titanium and zirconium are consistent with the prediction from the proposed nucleation model and the temperature-dependent mobility of twin dislocations. Alloying effects on twinning and future research areas are discussed. C1 MICHIGAN TECHNOL UNIV,DEPT MET & MAT ENGN,HOUGHTON,MI 49931. RP YOO, MH (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831, USA. NR 51 TC 137 Z9 142 U1 5 U2 56 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 1991 VL 63 IS 5 BP 987 EP 1000 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA FT785 UT WOS:A1991FT78500017 ER PT J AU CAPONETTI, E DAGUANNO, EM TRIOLO, R SPOONER, S AF CAPONETTI, E DAGUANNO, EM TRIOLO, R SPOONER, S TI KINETICS OF PARTICLE GROWTH AND PARTICLE COMPOSITION OF A COMMERCIAL AL-LI ALLOY BY MEANS OF SMALL-ANGLE SCATTERING SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID X-RAY-SCATTERING; MISCIBILITY GAP; SYSTEM AB Extending previous work done on a similar alloy, small-angle X-ray scattering measurements are reported for a commercial Al-Cu-Li alloy (2.68% Cu and 1.88% Li by weight). Data have been analysed by means of an ellipsoidal model of precipitate particles using a method previously proposed by some of us which, incorporating interparticle interference effects, reproduces the full scattering intensities of the samples studied. Particle dimensions obtained from the fit indicate that the Lifshitz-Slyozov coarsening mechanism holds for ageing at higher temperatures and longer times. The activation energy for volume diffusivity obtained is similar to that of pure binary alloys. The scattering-curve fitting parameters include the volume fractions of the delta'-phase which decrease as expected with increasing temperature. The scattering contrast between delta' and the matrix is observed to increase with temperature. On the basis of these observations, it would appear that the lithium concentrations in both the matrix and the precipitate increase with increasing temperature. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN. RP CAPONETTI, E (reprint author), UNIV PALERMO,DIPARTMENTO CHIM FIS,VIA ARCHIRAFI 26,I-90123 PALERMO,ITALY. OI CAPONETTI, Eugenio/0000-0003-0218-8556 NR 22 TC 20 Z9 20 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD MAY PY 1991 VL 63 IS 5 BP 1201 EP 1212 DI 10.1080/13642819108207597 PG 12 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA FT786 UT WOS:A1991FT78600017 ER PT J AU JOO, GC TSAKALAKOS, T CHEN, SP AF JOO, GC TSAKALAKOS, T CHEN, SP TI MODELING THE GROWTH OF NIAL EPILAYER ON ZINCBLENDE SUBSTRATE SO PHILOSOPHICAL MAGAZINE LETTERS LA English DT Article ID V-COMPOUND SEMICONDUCTORS; INTERMETALLIC FILMS; GRAIN-BOUNDARIES; SURFACES; STABILITY; EPITAXY; METALS; NI3AL AB Interface structure and epitaxial growth of NiAl on III-V or II-VI zinc-blende substrate have been studied by using the embedded atom method. Simulation showed that the {001} NiAl on {001} zinc-blende substrate forms a stable epitaxy only if a Ni monolayer is predeposited. A new model for the NiAl-zinc blende substrate interface is proposed. The investigation of d-spacing changes in the intermetallic overlayer showed anomalies near the interface and free surface, and this behaviour is expected to affect the properties of the epilayer. C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP JOO, GC (reprint author), RUTGERS STATE UNIV,DEPT MECH & MAT SCI,PISCATAWAY,NJ 08855, USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0950-0839 J9 PHIL MAG LETT JI Philos. Mag. Lett. PD MAY PY 1991 VL 63 IS 5 BP 249 EP 256 DI 10.1080/09500839108214652 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA FT783 UT WOS:A1991FT78300001 ER PT J AU CHOU, PT STUDER, SL MARTINEZ, ML ORTON, E YOUNG, M AF CHOU, PT STUDER, SL MARTINEZ, ML ORTON, E YOUNG, M TI PHOTOOXYGENATION OF 3-HYDROXYFLAVONE IN A 12-K O2 MATRIX SO PHOTOCHEMISTRY AND PHOTOBIOLOGY LA English DT Article ID INTRAMOLECULAR PROTON-TRANSFER; FLUORESCENCE-EXCITATION; PHOTOINDUCED REACTIONS; TRANSFER LASER; TRIPLET-STATE; GROUND-STATE; TIME AB We present an infrared study of 3-hydroxyflavone in 12 K Ar and O2 matrices. Although it is extremely photostable in an Ar matrix, a remarkable oxygenation reaction for 3-hydroxyflavone takes place upon photoexcitation in an O2 matrix. The primary photoproduct is concluded to be a keto-hydroperoxide. On further photolysis the keto-hydroperoxide affords the photostable secondary product 2-(benzoyloxyl)benzoic acid, as well as CO and CO2 through two independent pathways. C1 UNIV IOWA,CTR LASER SCI & ENGN,IOWA CITY,IA 52242. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CHEM BIODYNAM LAB,BERKELEY,CA 94720. RP CHOU, PT (reprint author), UNIV S CAROLINA,DEPT CHEM,COLUMBIA,SC 29208, USA. NR 25 TC 4 Z9 4 U1 0 U2 0 PU AMER SOC PHOTOBIOLOGY PI AUGUSTA PA BIOTECH PARK, 1021 15TH ST, SUITE 9, AUGUSTA, GA 30901-3158 SN 0031-8655 J9 PHOTOCHEM PHOTOBIOL JI Photochem. Photobiol. PD MAY PY 1991 VL 53 IS 5 BP 587 EP 593 PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA FL736 UT WOS:A1991FL73600002 ER PT J AU MAPLE, MB DALICHAOUCH, Y LEE, BW SEAMAN, CL TSAI, PK ARMSTRONG, PE FISK, Z ROSSEL, C TORIKACHVILI, MS AF MAPLE, MB DALICHAOUCH, Y LEE, BW SEAMAN, CL TSAI, PK ARMSTRONG, PE FISK, Z ROSSEL, C TORIKACHVILI, MS TI EVIDENCE FOR UNCONVENTIONAL SUPERCONDUCTIVITY IN SINGLE-CRYSTALS OF THE ANTIFERROMAGNETIC HEAVY-ELECTRON COMPOUND URU2SI2 SO PHYSICA B LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON VALENCE FLUCTUATIONS CY JUL 09-13, 1990 CL RIO DE JANEIRO, BRAZIL SP CONSELHO NACL PESQUISAS, FINANCIADORA ESTUDOS & PROJETOS, FUNDACAO AMPARO PESQUISA SAO PAULO, FUNDACAO AMPARO PESQUISA RIO DE JANEIRO, FUNDACAO AMPARO PESQUISA RIO GRANDE DO SUL, IBM BRAZIL, NATL SCI FDN, INT CTR THEORET PHYS, UNIV CAMPINAS ID CRITICAL MAGNETIC-FIELD; FERMION SUPERCONDUCTORS; PHASE-DIAGRAM; UPT3; UBE13; SYSTEM; ORDER; FLUCTUATIONS; TRANSITIONS; INSTABILITY AB Specific heat C(T) and upper critical field H(c2)(T) measurements have been performed on two single crystal specimens (denoted A and B) of the antiferromagnetic heavy-electron superconductor URu2Si2. Specific heat measurements on both single crystals reveal two distinct jumps, indicative of two superconducting phases. This is reminiscent of the antiferromagnetic heavy-electron compound UPt3 in which multiple superconducting transitions have been observed and attributed to coupled antiferromagnetic and multicomponent superconducting order parameters, although two superconducting phases associated with two different states of the crystal cannot be ruled out. The relative magnitudes of the two specific heat jumps observed in crystal B suggest that the two superconducting phases occupy nearly equal volume fractions of the crystal. At temperatures below the lower jump, the specific heat of both crystals can be described by C(s)(T) = gamma-s(0)T + AT3 with gamma-s(0) almost-equal-to 0.5-gamma-n(0), where gamma-n(0) is the value of the normal-state electronic specific heat coefficient gamma-n(T), extrapolated to T = 0. The two critical temperatures inferred from the specific heat jumps in crystal B, measured in magnetic fields H between 0 and 15 kOe applied parallel to the c-axis, have a similar dependence on H. Resistive measurements of H(c2)(T) on specimens from crystal A between 0 and 60 kOe reveal a kink near 2 kOe for H parallel-to c and strong positive curvature in H(c2)(T) below approximately 3 kOe for H parallel-to a. C1 UNIV CALIF SAN DIEGO,INST PURE & APPL PHYS SCI,LA JOLLA,CA 92093. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. IBM CORP,ZURICH RES LAB,CH-8803 RUSCHLIKON,SWITZERLAND. SAN DIEGO STATE UNIV,DEPT PHYS,SAN DIEGO,CA 92182. RP MAPLE, MB (reprint author), UNIV CALIF SAN DIEGO,DEPT PHYS,LA JOLLA,CA 92093, USA. NR 33 TC 13 Z9 13 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1991 VL 171 IS 1-4 BP 219 EP 225 DI 10.1016/0921-4526(91)90519-K PG 7 WC Physics, Condensed Matter SC Physics GA FU470 UT WOS:A1991FU47000037 ER PT J AU HUNDLEY, MF CANFIELD, PC THOMPSON, JD FISK, Z LAWRENCE, JM AF HUNDLEY, MF CANFIELD, PC THOMPSON, JD FISK, Z LAWRENCE, JM TI EVIDENCE FOR A COHERENCE GAP IN CE3BI4PT3 SO PHYSICA B LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON VALENCE FLUCTUATIONS CY JUL 09-13, 1990 CL RIO DE JANEIRO, BRAZIL SP CONSELHO NACL PESQUISAS, FINANCIADORA ESTUDOS & PROJETOS, FUNDACAO AMPARO PESQUISA SAO PAULO, FUNDACAO AMPARO PESQUISA RIO DE JANEIRO, FUNDACAO AMPARO PESQUISA RIO GRANDE DO SUL, IBM BRAZIL, NATL SCI FDN, INT CTR THEORET PHYS, UNIV CAMPINAS ID KONDO AB We present the results of electronic transport, magnetic susceptibility, and thermodynamic measurements on single crystals of the cubic compound Ce3Bi4Pt3. The susceptibility displays a broad peak centered at T(max) = 80 K, which in Ce compounds is usually indicative of mixed valence and moderately heavy-electron behavior. Both the electronic transport properties and the low-temperature specific heat indicate that Ce3Bi4Pt4 is nonmetallic with a transport energy gap of roughly 35 K. We argue that this temperature is close to that scale over which coherence should develop in a periodic metallic system with T(max) = 80 K. Resistivities typical of a Kondo-impurity system are realized when the compound is alloyed with moderate amounts of lanthanum. Further, lanthanum substitution increases the low-temperature specific heat to a value consistent with the single-ion energy scale determined from the magnetic susceptibility. C1 UNIV CALIF IRVINE,DEPT PHYS,IRVINE,CA 92717. RP HUNDLEY, MF (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. RI Canfield, Paul/H-2698-2014 NR 17 TC 43 Z9 43 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1991 VL 171 IS 1-4 BP 254 EP 257 DI 10.1016/0921-4526(91)90525-J PG 4 WC Physics, Condensed Matter SC Physics GA FU470 UT WOS:A1991FU47000043 ER PT J AU NEUMANN, KU BROWN, PJ CAPELLMANN, H ZIEBECK, KRA SMITH, JL FISK, Z FRANSE, JJM MENOVSKY, A AF NEUMANN, KU BROWN, PJ CAPELLMANN, H ZIEBECK, KRA SMITH, JL FISK, Z FRANSE, JJM MENOVSKY, A TI A COMPARISON OF THE STATIC MAGNETIC-FIELD INDUCED MAGNETIZATION DENSITIES IN UPT3 AND UBE13 SO PHYSICA B LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON VALENCE FLUCTUATIONS CY JUL 09-13, 1990 CL RIO DE JANEIRO, BRAZIL SP CONSELHO NACL PESQUISAS, FINANCIADORA ESTUDOS & PROJETOS, FUNDACAO AMPARO PESQUISA SAO PAULO, FUNDACAO AMPARO PESQUISA RIO DE JANEIRO, FUNDACAO AMPARO PESQUISA RIO GRANDE DO SUL, IBM BRAZIL, NATL SCI FDN, INT CTR THEORET PHYS, UNIV CAMPINAS ID HEAVY AB The static magnetic field induced magnetisation densities of two uranium based heavy-fermion systems have been determined in spin polarised neutron scattering experiments at temperatures of T = 5 K and T = 10 K, respectively. Both compounds show a significantly different magnetisation density. The various contributions are identified. In UPt3 the polarisation of conduction electrons is important, but in contrast the magnetisation density in UBe13 is observed to be of a pure uranium 5f-electron character with no indication of any conduction electron contribution due to polarization by the external magnetic field. Both heavy-fermion compounds have in common a small value of the aligned 5f-electron magnetic moment which is well described by a spherically symmetric model. However, UPt3 and UBe13 differ significantly in the contributions of the conductions electrons. C1 INST MAX VON LAUE PAUL LANGEVIN,F-38042 GRENOBLE,FRANCE. RHEIN WESTFAL TH AACHEN,INST THEORET PHYS,W-5100 AACHEN,GERMANY. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87544. UNIV AMSTERDAM,NATUURKUNDIG LAB,AMSTERDAM,NETHERLANDS. RP NEUMANN, KU (reprint author), LOUGHBOROUGH UNIV TECHNOL,DEPT PHYS,LOUGHBOROUGH,ENGLAND. NR 3 TC 1 Z9 1 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1991 VL 171 IS 1-4 BP 273 EP 277 DI 10.1016/0921-4526(91)90530-R PG 5 WC Physics, Condensed Matter SC Physics GA FU470 UT WOS:A1991FU47000048 ER PT J AU BEYERMANN, WP HUNDLEY, MF CANFIELD, PC GODART, C SELSANE, M FISK, Z SMITH, JL THOMPSON, JD AF BEYERMANN, WP HUNDLEY, MF CANFIELD, PC GODART, C SELSANE, M FISK, Z SMITH, JL THOMPSON, JD TI ANTIFERROMAGNETISM AND ENHANCED SPECIFIC-HEAT IN CEM2SN2 (M = NI, IR, CU, RH, PD AND PT) SO PHYSICA B LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON VALENCE FLUCTUATIONS CY JUL 09-13, 1990 CL RIO DE JANEIRO, BRAZIL SP CONSELHO NACL PESQUISAS, FINANCIADORA ESTUDOS & PROJETOS, FUNDACAO AMPARO PESQUISA SAO PAULO, FUNDACAO AMPARO PESQUISA RIO DE JANEIRO, FUNDACAO AMPARO PESQUISA RIO GRANDE DO SUL, IBM BRAZIL, NATL SCI FDN, INT CTR THEORET PHYS, UNIV CAMPINAS ID KONDO LATTICE AB Specific heat, DC susceptibility, and resistivity measurements on annealed, polycrystalline samples of CeM2Sn2, where M = Ni, Ir, Cu, Rh, Pd, or Pt, indicate that each of these compounds orders antiferromagnetically with transition temperatures ranging from T(N) = 4.1 to almost-equal-to 0.5 K. All these materials have significant enhancements of the specific heat just before the transition, which can be as large as approximately 3.5 J/mol K2 in some cases. Provided the enhanced heat capacities above T(N) are associated with large effective masses, the anomalously low ordering temperature and the very large C/T suggest that T(N) and the Kondo temperature T(K) are comparable, making these materials particularly attractive for studying the interplay between these competing interactions. The susceptibility for each member of the series except M = Ir follows a Curie-Weiss behavior with a high-temperature effective moment mu-eff approximately 2.5-mu-B/Ce and a small negative paramagnetic Curie temperature. C1 CNRS,UPR 209,F-92190 MEUDON,FRANCE. RP BEYERMANN, WP (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. RI Canfield, Paul/H-2698-2014 NR 14 TC 24 Z9 24 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1991 VL 171 IS 1-4 BP 373 EP 376 DI 10.1016/0921-4526(91)90553-Q PG 4 WC Physics, Condensed Matter SC Physics GA FU470 UT WOS:A1991FU47000071 ER PT J AU MACLAUGHLIN, DE REYES, AP TAKIGAWA, M HAMMEL, PC HEFFNER, RH THOMPSON, JD CROW, JE AF MACLAUGHLIN, DE REYES, AP TAKIGAWA, M HAMMEL, PC HEFFNER, RH THOMPSON, JD CROW, JE TI COPPER NMR AND HOLE DEPLETION IN THE NORMAL STATE OF Y1-XPRXBA2CU3O7 SO PHYSICA B-CONDENSED MATTER LA English DT Article ID NUCLEAR-RESONANCE; KNIGHT-SHIFT; CU-NMR; YBA2CU3O7; SUPERCONDUCTIVITY; RELAXATION; BEHAVIOR; OXYGEN; FIELD; PHASE AB Normal-state copper NMR spectra and spin-lattice relaxation rates 1/T1 have been measured in the planar cuprate system Y1-xPr(x)Ba2Cu3O7. The Knight shift K decreases with Pr doping and develops a temperature dependence at chain sites. Analysis of the bulk susceptibility and NMR data indicates that pair breaking and hole depletion both take part in the suppression of the superconducting transition temperature T(c). The Knight shift behavior resembles that in oxygen-deficient YBa2Cu3O7-y, as does the temperature dependence of 1/T1 for plane Cu sites and magnetic field perpendicular to the c axis. This agreement leads to a consistent picture of the role of antiferromagnetic fluctuations in these materials. An analysis of the data in the framework of the phenomenological theory of Millis, Monien and Pines is given. In the end compound PrBa2Cu3O7 the NMR signal from plane Cu sites indicates antiferromagnetic (AF) ordering at a Neel temperature approximately 280 K, and in the AF state yields and internal field similar to those found in AF YBa2Cu3O6 and La2CuO4. C1 UNIV CALIF LOS ALAMOS SCI LAB, LOS ALAMOS, NM 87545 USA. TEMPLE UNIV, PHILADELPHIA, PA 19122 USA. FLORIDA STATE UNIV, TALLAHASSEE, FL 32306 USA. RP MACLAUGHLIN, DE (reprint author), UNIV CALIF RIVERSIDE, RIVERSIDE, CA 92521 USA. RI Hammel, P Chris/O-4845-2014 OI Hammel, P Chris/0000-0002-4138-4798 NR 38 TC 11 Z9 11 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1991 VL 171 IS 1-4 BP 245 EP 253 DI 10.1016/0921-4526(91)90524-I PG 9 WC Physics, Condensed Matter SC Physics GA FU470 UT WOS:A1991FU47000042 ER PT J AU KWEI, GH LAWSON, AC HULTS, WL SMITH, JL AF KWEI, GH LAWSON, AC HULTS, WL SMITH, JL TI VIBRATIONAL PROPERTIES AND ATOMIC DEBYE TEMPERATURES FOR YBA2CU3O7 FROM NEUTRON POWDER DIFFRACTION SO PHYSICA C LA English DT Article ID SUPERCONDUCTING TRANSITION; STRUCTURAL ANOMALIES; LATTICE-DYNAMICS; TC; CU; DEPENDENCE AB Neutron powder diffraction data taken at twelve sample temperatures have been used to determine both isotropic and anisotropic thermal parameters for atoms in YBa2Cu3O7. At fit of these parameters to a Debye-Waller model in turn yields the corresponding isotropic and anisotropic Debye-Waller temperatures. The anisotropic thermal parameters for the Y, Ba and the planar Cu(2) and O(2) atoms all exhibit a stronger temperature dependence, and therefore a lower Debye-Waller temperature, for motion along the c-axis; in addition, the chain O(1) atoms show a similar strong temperature dependence for motion perpendicular to the chains. No discontinuities in the thermal parameters, suggestive of possible structural changes or phonon anomalies near T(c) are observed. RP KWEI, GH (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 34 TC 16 Z9 16 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 1991 VL 175 IS 5-6 BP 615 EP 622 DI 10.1016/0921-4534(91)90274-3 PG 8 WC Physics, Applied SC Physics GA FM746 UT WOS:A1991FM74600017 ER PT J AU CHANNELL, PJ SCOVEL, JC AF CHANNELL, PJ SCOVEL, JC TI INTEGRATORS FOR LIE-POISSON DYNAMIC-SYSTEMS SO PHYSICA D LA English DT Article ID SYMPLECTIC INTEGRATION AB We reformulate the Ge-Marsden (1988) Lie-Poisson integration algorithm in terms of algebra variables alone and show how to implement it for regular quadratic Lie algebras to arbitrary order and for arbitrary Lie algebras to first order. We also describe two generalizations of Ruth's method (1983) that can be used to generate very fast algorithms. C1 UNIV CALIF LOS ALAMOS SCI LAB,COMP RES GRP,LOS ALAMOS,NM 87545. RP CHANNELL, PJ (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,ACCELERATOR THEORY & SIMULAT GRP,AT-6,MS-H829,LOS ALAMOS,NM 87545, USA. NR 27 TC 39 Z9 39 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD MAY PY 1991 VL 50 IS 1 BP 80 EP 88 DI 10.1016/0167-2789(91)90081-J PG 9 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA FR044 UT WOS:A1991FR04400008 ER PT J AU COHEN, JS AF COHEN, JS TI IMPROVED ADIABATIC CALCULATION OF MUONIC-HYDROGEN-ATOM CROSS-SECTIONS .2. HYPERFINE TRANSITIONS AND ELASTIC-SCATTERING IN SYMMETRICAL COLLISIONS SO PHYSICAL REVIEW A LA English DT Article ID DEUTERIUM; FUSION AB The improved adiabatic representation is used in calculations of elastic and hyperfine-transition cross sections for symmetric collisions of p-mu, d-mu, and t-mu with bare p, d, and t nuclei and with H, D, and T atoms, respectively. The cross sections for d-mu + d and t-mu + t are in excellent agreement with other recent determinations, while those for p-mu + p are about 30% larger at low energies. The electronic screening is calculated nonperturbatively and found to be about 30% smaller in magnitude than the previously calculated value at large internuclear distances, and to deviate considerably from the asymptotic form in the molecular region. The resulting screened elastic cross sections are up to 60% smaller than those obtained using the old screening potential. The reactance matrices, needed for calculations of molecular-target effects, are given in tables. RP COHEN, JS (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 30 TC 31 Z9 31 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY 1 PY 1991 VL 43 IS 9 BP 4668 EP 4683 DI 10.1103/PhysRevA.43.4668 PG 16 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FL111 UT WOS:A1991FL11100012 ER PT J AU MANSON, ST THEODOSIOU, CE INOKUTI, M AF MANSON, ST THEODOSIOU, CE INOKUTI, M TI SPECTRAL AND ELECTRON-COLLISION PROPERTIES OF ATOMIC IONS .2. INNER-SHELL PROPERTIES SO PHYSICAL REVIEW A LA English DT Article ID VALUES AB In this report, a follow-up to our earlier paper [Theodosiou, Manson, and Inokuti, Phys. Rev. A 34, 943 (1986)] on comprehensive calculations of various properties of all atomic ions in all stages of ionization with nuclear charge Z less-than-or-equal-to 50, we investigate, within the Hartree-Slater approximation, inner-shell properties including orbital binding energies, x-ray transition energies and rates, photoionization cross sections, and expectation values of powers of electron radial coordinates. Throughout we concentrate on enumerating general trends of the properties as functions of the nuclear charge Z and the total electron number N. The systematics thus found for highly stripped ions (i.e., for ions in which Z-N is appreciable) are interpreted in terms of the outer-shell screening and the hydrogenic shell structure in which complete shells occur at N = n(n + 1)(2n + 1)/3 = 2, 10, 28, 60, ..., for principal quantum numbers n = 1,2, 3, 4, ..., respectively. C1 UNIV TOLEDO,DEPT PHYS & ASTRON,TOLEDO,OH 43606. ARGONNE NATL LAB,ARGONNE,IL 60439. RP MANSON, ST (reprint author), GEORGIA STATE UNIV,DEPT PHYS & ASTRON,ATLANTA,GA 30303, USA. NR 22 TC 4 Z9 4 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY 1 PY 1991 VL 43 IS 9 BP 4688 EP 4694 DI 10.1103/PhysRevA.43.4688 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FL111 UT WOS:A1991FL11100014 ER PT J AU PRATT, ST DEHMER, PM DEHMER, JL AF PRATT, ST DEHMER, PM DEHMER, JL TI DOUBLE-RESONANCE SPECTROSCOPY OF TRANSITIONS BETWEEN AUTOIONIZING LEVELS OF ATOMIC OXYGEN SO PHYSICAL REVIEW A LA English DT Article ID 2-PHOTON EXCITATION; PHOTOIONIZATION; STATES; IONIZATION AB Double-resonance spectroscopy is used to study transitions between autoionizing levels of atomic oxygen. The first laser is used to produce oxygen atoms in the 1s(2)2s(2)2p(4)1D2 level by photodissociation of N2O and to excite two-photon transitions from the 1D2 level to the long-lived (2D-degrees)3p 1F3 autoionizing level. The second laser is used to probe transitions from the 1F3 level to higher-energy autoionizing levels as well as to the O+ 2D-degrees direct-ionization continuum. The transitions are detected by using a magnetic bottle electron spectrometer to monitor photoelectrons selectively with the kinetic energy specific to the process of interest. New transitions to the (2D-degrees-5/2,3/2)ns' and nd' Rydberg-series members with n = 16 - 31 are observed. The intensity dependence of these results has also been studied, and the implications of this relatively low-power measurement for above-threshold ionization are discussed. RP PRATT, ST (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 37 TC 19 Z9 19 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY 1 PY 1991 VL 43 IS 9 BP 4702 EP 4711 DI 10.1103/PhysRevA.43.4702 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FL111 UT WOS:A1991FL11100016 ER PT J AU DINNEEN, TP MANSOUR, NB KURTZ, C YOUNG, L AF DINNEEN, TP MANSOUR, NB KURTZ, C YOUNG, L TI STIMULATED RAMAN MEASUREMENTS OF THE HYPERFINE-STRUCTURE IN Y-II SO PHYSICAL REVIEW A LA English DT Article ID RF DOUBLE-RESONANCE; SPECTROSCOPY AB Stimulated Raman spectroscopy has been used in a fast ion beam to measure the hyperfine structure in the 4d2 configuration of Y II. A simple theory is provided for the line shape of the coherent two-photon transition which gives a transit-time limited linewidth of 0.9/T, comparable to the resolution of the laser-radio-frequency double-resonance technique. The hyperfine structure is compared with a multiconfiguration Dirac-Fock calculation and with that of the homologous Sc II ion. This comparison confirms the role of core polarization as a significant factor in the hyperfine structure of these ions. RP DINNEEN, TP (reprint author), ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439, USA. RI Kurtz, Chalres/G-1037-2011 OI Kurtz, Chalres/0000-0003-2606-0864 NR 19 TC 15 Z9 15 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY 1 PY 1991 VL 43 IS 9 BP 4824 EP 4831 DI 10.1103/PhysRevA.43.4824 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FL111 UT WOS:A1991FL11100028 ER PT J AU PENETRANTE, BM BARDSLEY, JN DEWITT, D CLARK, M SCHNEIDER, D AF PENETRANTE, BM BARDSLEY, JN DEWITT, D CLARK, M SCHNEIDER, D TI EVOLUTION OF ION-CHARGE-STATE DISTRIBUTIONS IN AN ELECTRON-BEAM ION TRAP SO PHYSICAL REVIEW A LA English DT Article ID EXCITATION CROSS-SECTIONS; RECOMBINATION; ATOMS AB We present measurements and calculations of the evolution of the ion-charge-state distributions in an electron-beam ion trap. Direct measurements of the charge-state distributions are made with an ion extraction system. The data are used to test our computer model, which solves the set of coupled nonlinear differential equations for the energy and charge balance for all ionic species. The model is used to assess the importance of various processes in establishing the charge-state distribution. RP PENETRANTE, BM (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DIV HIGH TEMP PHYS,LIVERMORE,CA 94550, USA. NR 21 TC 89 Z9 89 U1 0 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY 1 PY 1991 VL 43 IS 9 BP 4861 EP 4872 DI 10.1103/PhysRevA.43.4861 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FL111 UT WOS:A1991FL11100033 ER PT J AU PENETRANTE, BM BARDSLEY, JN LEVINE, MA KNAPP, DA MARRS, RE AF PENETRANTE, BM BARDSLEY, JN LEVINE, MA KNAPP, DA MARRS, RE TI EVAPORATIVE COOLING OF HIGHLY CHARGED DYSPROSIUM IONS IN AN ENHANCED ELECTRON-BEAM ION TRAP SO PHYSICAL REVIEW A LA English DT Article ID EXCITATION CROSS-SECTIONS; ATOMS; IMPACT; RECOMBINATION AB The mechanism of evaporative cooling of highly charged ions in an electron-beam ion trap (EBIT) is discussed. Computer simulations of evaporative cooling in superEBIT indicate that with the use of neon, nitrogen, or helium coolants, significant amounts of bare and hydrogenlike dysprosium ions can be trapped indefinitely for the observation of bound-state beta-decay. RP PENETRANTE, BM (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DIV HIGH TEMP PHYS,LIVERMORE,CA 94550, USA. NR 24 TC 41 Z9 41 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY 1 PY 1991 VL 43 IS 9 BP 4873 EP 4882 DI 10.1103/PhysRevA.43.4873 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FL111 UT WOS:A1991FL11100034 ER PT J AU GARRISON, JC RITCHIE, B NATHEL, H HONG, CK MINNER, L AF GARRISON, JC RITCHIE, B NATHEL, H HONG, CK MINNER, L TI WAVE-OPTICS DESCRIPTION OF AMPLIFIED SPONTANEOUS EMISSION SO PHYSICAL REVIEW A LA English DT Article ID SIGNAL AMPLIFICATION; QUANTUM-THEORY; IONIZATION AB Paraxial Maxwell-Bloch theory is used to describe amplified spontaneous emission (ASE) in strongly inverted media. Counterpropagation of waves coupled through gain saturation and diffraction, and pumping by a laser beam which propagates transverse to the amplifier are included in the treatment. The reactive part of the medium polarization is calculated by population-rate equations in the limit of rapid dephasing of the atomic dipoles. The spontaneous emission noise source needed for the numerical simulation of Maxwell's equations is derived from microscopic theory by coarse-graining, thereby establishing the compatibility of the spherically symmetric microscopic source with paraxial propagation theory. The three coupled Maxwell equations for the counterpropagating ASE waves and the transversely propagating pump wave are solved numerically in time and two spatial dimensions. This simulation is used to calculate the longitudinal profile of the transverse fluorescence, which measures the saturation of the gain, the longitudinal profile of the transmitted pump wave, which measures the saturation of pump absorption, and the transverse coherence function of the radiation emitted from the ends of the amplifier. RP GARRISON, JC (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 17 TC 10 Z9 10 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY 1 PY 1991 VL 43 IS 9 BP 4941 EP 4953 DI 10.1103/PhysRevA.43.4941 PG 13 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FL111 UT WOS:A1991FL11100041 ER PT J AU LAGATTUTA, KJ AF LAGATTUTA, KJ TI MULTIPHOTON IONIZATION RATES FOR ATOMIC-HYDROGEN - LINEAR AND CIRCULAR-POLARIZATION COMPARED SO PHYSICAL REVIEW A LA English DT Note ID LASER FIELDS; PHOTOIONIZATION AB Previously reported calculations of the photoionization rate for atomic hydrogen interacting with a linearly polarized laser beam have been repeated using an improved computer algorithm. Good agreement now exists between our calculated rates and those predicted by three other groups [M. Pindzola (private communication); K. Kulander (private communication); S. Chu and J. Cooper, Phys. Rev. A 32, 2769 (1985)]. Our results are, however, in apparent disagreement with reported measurements of these rates [T. Nichols and G. Kyrala, Bull. Am. Soc. 35, 1156 (1990)]. Calculations are also reported of the photoionization rates for atomic hydrogen interacting with a circularly polarized laser beam. Results for linear and circular polarizations are compared with each other, as well as with the predictions of several analytic formulas [L. Keldysh, Sov. Phys-JETP 20, 1307 (1965); H. Reiss, J. Opt. Soc. Am. B 4, 726 (1987)]. RP LAGATTUTA, KJ (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV APPL THEORET PHYS,LOS ALAMOS,NM 87545, USA. NR 15 TC 31 Z9 31 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY 1 PY 1991 VL 43 IS 9 BP 5157 EP 5160 DI 10.1103/PhysRevA.43.5157 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FL111 UT WOS:A1991FL11100070 ER PT J AU SCHUCH, R JUSTINIANO, E SCHULZ, M DATZ, S DITTNER, PF GIESE, JP KRAUSE, HF SCHONE, H VANE, R SHAFROTH, S AF SCHUCH, R JUSTINIANO, E SCHULZ, M DATZ, S DITTNER, PF GIESE, JP KRAUSE, HF SCHONE, H VANE, R SHAFROTH, S TI POPULATION OF HIGHLY EXCITED INTERMEDIATE RESONANCE STATES BY ELECTRON-TRANSFER AND EXCITATION SO PHYSICAL REVIEW A LA English DT Note ID LIGHT TARGETS; COLLISIONS; IONS; H-2 AB Coincidences between two sulfur K x rays were detected from collisions of hydrogenlike S ions with H-2 gas in the projectile energy range between 150 and 225 MeV. These K x rays are emitted in the decay of doubly excited states formed in the collisions via transfer and excitation. The excitation function for two coincident K-beta transitions peaks at about 175 MeV, slightly above the expected KMM resonance energy for resonant transfer and excitation (RTE). This demonstrates the occurrence of DELTA-N greater-than-or-equal-to 2 transitions (i.e., KMM and higher resonances) in the RTE process. The cross sections for the population of the very highly excited states are higher than those predicted by theoretical calculations that use dielectronic recombination rates folded with the Compton profile for the bound electrons. C1 E CAROLINA UNIV,DEPT PHYS,GREENVILLE,NC 27834. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. N CAROLINA STATE UNIV,DEPT PHYS,CHAPEL HILL,NC 27599. RP SCHUCH, R (reprint author), MANNE SIEGBAHN INST PHYS,S-10405 STOCKHOLM,SWEDEN. NR 15 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY 1 PY 1991 VL 43 IS 9 BP 5180 EP 5183 DI 10.1103/PhysRevA.43.5180 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FL111 UT WOS:A1991FL11100078 ER PT J AU SOININEN, E SCHWAB, A LYNN, KG AF SOININEN, E SCHWAB, A LYNN, KG TI POSITRON-INDUCED AUGER-ELECTRON STUDY OF THE GE(100) SURFACE - POSITRON THERMAL-DESORPTION AND SURFACE CONDITION SO PHYSICAL REVIEW B LA English DT Article ID METAL-SURFACES; TEMPERATURE-DEPENDENCE; EMISSION; SPECTROSCOPY; ANNIHILATION; TRANSITIONS; DIFFUSION; OXYGEN; STATES; AL AB Positron-annihilation-induced Auger-electron spectroscopy (PAES) was used to study the effects of oxygen, residual gases, and temperature on a Ge(100) surface. Three low-energy Auger peaks were detected at 50, 90, and 100-150 eV, attributed to M2, 3M4M4, M2, 3M4V, and M1M4M4 Auger transitions, respectively. An estimated (4 +/- 1)% of the surface-trapped positrons annihilate with Ge 3p-level electrons. The sensitivity of PAES to the surface condition is demonstrated. The PAES yield from a Ge(100) surface is reduced at elevated temperatures, in accord with an activation process earlier found in several positronium (Ps) -fraction experiments. A desorption model adopted from these studies does not describe accurately the PAES results at higher temperatures (> 500-degrees-C), where the PAES intensity levels off to 5% of the room-temperature value. Possible sources for the discrepancy are discussed and models for positron trapping to deep surface traps are introduced. On the Ge(100) surface, an upper limit for Ps emission near the melting point is 97%. The error in calibration parameters due to the earlier assumption of 100% Ps emission seems to introduce only small errors into the Ps-fraction measurements. C1 HELSINKI UNIV TECHNOL,PHYS LAB,SF-02150 ESPOO 15,FINLAND. UNIV BIELEFELD,FAK PHYS,W-4800 BIELEFELD,GERMANY. RP SOININEN, E (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 48 TC 28 Z9 28 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 10051 EP 10061 DI 10.1103/PhysRevB.43.10051 PN A PG 11 WC Physics, Condensed Matter SC Physics GA FL039 UT WOS:A1991FL03900004 ER PT J AU GAO, F CARR, GL PORTER, CD TANNER, DB ETEMAD, S VENKATESAN, T INAM, A DUTTA, B WU, XD WILLIAMS, GP HIRSCHMUGL, CJ AF GAO, F CARR, GL PORTER, CD TANNER, DB ETEMAD, S VENKATESAN, T INAM, A DUTTA, B WU, XD WILLIAMS, GP HIRSCHMUGL, CJ TI FAR-INFRARED TRANSMITTANCE AND REFLECTANCE STUDIES OF ORIENTED YBA2CU3O7-DELTA THIN-FILMS SO PHYSICAL REVIEW B LA English DT Article ID NORMAL-STATE; SUPERCONDUCTORS; GAP; REFLECTIVITY; CONDUCTIVITY; SPECTROSCOPY AB We have measured both the transmittance (T) and reflectance (R) for several YBa2Cu3O7-delta thin films over the frequency range from 20 to 360 cm-1 at temperatures between 20 and 300 K. The films, grown on MgO substrates by pulsed laser ablation, are highly alpha-b-plane oriented. We use T and R to extract the optical conductivity, and find good agreement with results from Kramers-Kronig analysis of reflectance measurements alone. The transmittance is consistent with a two-component dielectric function consisting of Drude (free-carrier) and midinfrared (bound-carrier) absorption. The Drude relaxation rate varies linearly with temperature, and compares well with values obtained from the measured dc resistivity. We use a two-fluid model for the superconducting state and obtain a BCS-like temperature dependence for the superfluid density. A superconducting gap is not observed in our spectra. C1 BELL COMMUN RES INC,RED BANK,NJ 07701. RUTGERS STATE UNIV,DEPT PHYS,PISCATAWAY,NJ 08855. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP GAO, F (reprint author), UNIV FLORIDA,DEPT PHYS,GAINESVILLE,FL 32611, USA. RI Venkatesan, Thirumalai/E-1667-2013 NR 31 TC 54 Z9 54 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 10383 EP 10389 DI 10.1103/PhysRevB.43.10383 PN A PG 7 WC Physics, Condensed Matter SC Physics GA FL039 UT WOS:A1991FL03900042 ER PT J AU CREUTZ, M AF CREUTZ, M TI STATE COUNTING AND LOW-TEMPERATURE SERIES SO PHYSICAL REVIEW B LA English DT Article ID PARTITION-FUNCTION; ISING-MODEL; LATTICE AB I present a simple numerical technique for evaluating the low-temperature expansion for discrete statistical systems. I begin with a recursive procedure on finite lattices to count the states of a given energy. Comparing these numbers on different lattice sizes, I extract coefficients for the infinite-volume series. I test the method with the three-dimensional Ising model, obtaining the expansion of the average energy through terms involving 34 excited bonds. RP CREUTZ, M (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 6 TC 38 Z9 38 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 10659 EP 10662 DI 10.1103/PhysRevB.43.10659 PN A PG 4 WC Physics, Condensed Matter SC Physics GA FL039 UT WOS:A1991FL03900079 ER PT J AU FORINASH, K BISHOP, AR LOMDAHL, PS AF FORINASH, K BISHOP, AR LOMDAHL, PS TI NONLINEAR DYNAMICS IN A DOUBLE-CHAIN MODEL OF DNA SO PHYSICAL REVIEW B LA English DT Article ID DOUBLE HELICES; SOLITON EXCITATIONS AB We investigate numerically the mechanics of a simple lattice model of DNA. The model consists of two linear-mass chains connected by a Morse potential representing the hydrogen bonding between the sugar-phosphate backbones. Effects on discrete breather-type solutions caused by random noise and mass defects, representing interaction with the local environment, are studied. C1 UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RP FORINASH, K (reprint author), INDIANA UNIV SE,NEW ALBANY,IN 47150, USA. NR 17 TC 15 Z9 16 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 10743 EP 10750 DI 10.1103/PhysRevB.43.10743 PN A PG 8 WC Physics, Condensed Matter SC Physics GA FL039 UT WOS:A1991FL03900088 ER PT J AU FROTA, HO MAHAN, GD AF FROTA, HO MAHAN, GD TI SCREENED ANDERSON MODEL SO PHYSICAL REVIEW B LA English DT Article ID FALICOV-KIMBALL MODEL; PHASE-TRANSITIONS; HYBRIDIZATION AB The occupation number (n(f)) of the impurity orbital (f) in the Anderson model is calculated as a function of the orbital energy (epsilon-f), taking into account finite values for the Coulomb interactions between the impurity and the conduction electrons (G) and between two electrons inside of the localized orbital (U). For small values of G, the transitions f2 --> f1 --> f0 occur, with a step at n(f) = 1. By increasing G this step vanishes, with a direct transition f2 --> f0, which is a typical result of an effective U < 0. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN. UNIV AMAZONAS,INST CIENCIAS EXATAS,DEPT FIS,E-69068 MANAUS,SPAIN. RP FROTA, HO (reprint author), UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996, USA. NR 17 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 10755 EP 10760 DI 10.1103/PhysRevB.43.10755 PN A PG 6 WC Physics, Condensed Matter SC Physics GA FL039 UT WOS:A1991FL03900090 ER PT J AU KHACHATURYAN, AG SHAPIRO, SM SEMENOVSKAYA, S AF KHACHATURYAN, AG SHAPIRO, SM SEMENOVSKAYA, S TI ADAPTIVE PHASE FORMATION IN MARTENSITIC-TRANSFORMATION SO PHYSICAL REVIEW B LA English DT Article ID CRYSTAL-STRUCTURE; FCT AB It is shown that an appearance of an intermediate martensite phase called adaptive martensite may be expected if the surface energy of a boundary between two orientational variants of the normal martensite phase is very low and the typical lattice-mismatch-related elastic energy is high. The adaptive martensite is formed as an elastically constrained phase when the scale of structure heterogeneities induced by the crystal-strain accommodation is reduced to the microscopic scale commensurate with the twin-plane interplanar distance. An example of the cubic --> tetragonal transformation is considered where the adaptive phase has a pseudo-orthorhombic lattice. The crystal-lattice parameters of the adaptive phase are expressed through those of the parent cubic phase and tetragonal normal martensite. It is shown that the (5,2BAR)7R martensite in beta'NiAl alloys and the intermediate phase recently found just above the temperature of the fcc --> fct martensitic transformation in Fe-Pd are examples of the adaptive martensite. A possible role of the adaptive phase in the thermal nucleation of the martensite is discussed. The nucleation of the normal martensite may be bypassed by nucleation of the adaptive phase, which transforms to the normal martensite during the growth. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RP KHACHATURYAN, AG (reprint author), RUTGERS STATE UNIV,DEPT MECH & MAT SCI,POB 909,PISCATAWAY,NJ 08854, USA. NR 25 TC 223 Z9 224 U1 3 U2 55 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 10832 EP 10843 DI 10.1103/PhysRevB.43.10832 PN B PG 12 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100006 ER PT J AU PECHARSKY, VK GSCHNEIDNER, KA MILLER, LL AF PECHARSKY, VK GSCHNEIDNER, KA MILLER, LL TI LOW-TEMPERATURE HEAT-CAPACITY AND MAGNETIC-PROPERTIES OF THE RNIX2 COMPOUNDS (R = LA, CE, X = SI, GE, SN) SO PHYSICAL REVIEW B LA English DT Article AB Heat-capacity (1.4-80 K) and magnetic-susceptibility (1.5-300 K) measurements were carried out for the series of six ternary intermetallic compounds with RNiX2 composition (R = La, Ce and X = Si, Ge, and Sn). All of the LaNiX2 compounds exhibit normal metallic behavior with an electronic specific-heat coefficient in the range 5.2-5.6 mJ/mol K2 and Debye temperature decreasing from 451 K (LaNiSi2) to 258 K (LaNiSn2). The CeNiX2 compounds display anomalous behaviors. CeNiSi2 is an intermediate-valence compound at high temperatures with the cerium valence varying from 3.35+ at room temperature to 3.65+ at T = 50 K, and becomes a spin fluctuator at low (around 3.3 K) temperature. The spin fluctuations can be quenched by an external magnetic field of about 5.3 T. Both CeNiGe2 and CeNiSn2 undergo two-step antiferromagnetic phase transitions at T(N)II = 3.9 K and T(N)I = 3.2 K, which are accompanied by sharp anomalies for all properties studied. The electronic specific constants (in units of mJ/mol Ce K2) of the three Ce compounds were 45.3 +/- 0.6 for CeNiSi2, 97.6 +/- 0.9 for CeNiGe, and 60.8 +/- 0.7 for CeNiSn2. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT MAT SCI & ENGN,AMES,IA 50011. LVOV IVAN FRANKO STATE UNIV,DEPT INORGAN CHEM,LVOV 290005,UKRAINE,UKRAINE. RP PECHARSKY, VK (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 10 TC 56 Z9 56 U1 4 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 10906 EP 10914 DI 10.1103/PhysRevB.43.10906 PN B PG 9 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100013 ER PT J AU NAKANO, A VASHISHTA, P KALIA, RK AF NAKANO, A VASHISHTA, P KALIA, RK TI ELECTRON-TRANSPORT IN DISORDERED-SYSTEMS - A NONEQUILIBRIUM QUANTUM-MOLECULAR-DYNAMICS APPROACH SO PHYSICAL REVIEW B LA English DT Article ID EXCESS ELECTRONS; SIMPLE FLUIDS; BEHAVIOR; MOBILITY; HELIUM AB For mixed systems of quantum and classical particles, a simulation approach is developed to calculate the transport coefficients of quantum particles. Simulating the real-time evolution by quantum molecular dynamics, the response is obtained by applying a subtraction technique to the motion of quantum particles at zero and finite fields. This approach is efficient and yields a good signal-to-noise ratio. Using an excess-electron-in-helium gas as a test system, the mobility of the electron is calculated at a finite temperature and the results are found to be in good agreement with experiments. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. LOUISIANA STATE UNIV,DEPT PHYS & ASTRON,BATON ROUGE,LA 70803. NR 12 TC 9 Z9 9 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 10928 EP 10932 DI 10.1103/PhysRevB.43.10928 PN B PG 5 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100015 ER PT J AU LAWRENCE, JM HUNDLEY, MF THOMPSON, JD KWEI, GH FISK, Z AF LAWRENCE, JM HUNDLEY, MF THOMPSON, JD KWEI, GH FISK, Z TI COEXISTENCE OF MAGNETIC ORDER AND HEAVY-FERMION PARAMAGNETISM IN CE5SN3 SO PHYSICAL REVIEW B LA English DT Article ID FIELD AB We report resistivity, magnetic, thermodynamic, and neutron-diffraction data for the heavy-fermion compound Ce5Sn3. These data indicate an antiferromagnetic phase transition at T(N) = 17.5 K, but at lower temperatures the linear coefficient of specific heat gamma(T) = C(T)/T rises to 1.6 J/f.u. mol K2, characteristic of a moderately-heavy-fermion compound. Only a small amount of entropy is liberated by the phase transition (<< R 1n2), whereas most of the entropy [(3-4)R 1n2] is liberated by heavy-fermion processes. This implies a small ordered moment. Further, neutron diffraction implies a rather complicated magnetic order. We discuss two alternatives: (a) that ordering occurs on the Ce site of higher symmetry, while heavy-fermion behavior occurs on the lower-symmetry Ce site; and (b) that itinerant-fermion antiferromagnetism occurs. Due to the overall low site symmetries, crystal-field effects are strong; in particular, the susceptibility is highly anisotropic (by a factor of at least 20 at low temperatures) and enhanced by the presence of strong ferromagnetic correlations in the heavy-fermion state. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP LAWRENCE, JM (reprint author), UNIV CALIF IRVINE,DEPT PHYS,IRVINE,CA 92717, USA. NR 13 TC 14 Z9 14 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 11057 EP 11061 DI 10.1103/PhysRevB.43.11057 PN B PG 5 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100030 ER PT J AU ZHOU, Y BOWEN, SP KOELLING, DD MONNIER, R AF ZHOU, Y BOWEN, SP KOELLING, DD MONNIER, R TI MAGNETIC-SUSCEPTIBILITY OF YBN SO PHYSICAL REVIEW B LA English DT Article ID NORMAL-STATE PROPERTIES; LARGE-N EXPANSION; ANDERSON MODEL; KONDO PROBLEM; ALLOYS; IMPURITY AB Applying the Zwicknagl, Zevin, and Fulde (ZZF) approximation for the spectral densities of the occupied and empty f states resulting from a degenerate-Anderson-impurity model, which incorporates crystal fields, we compute the low-temperature magnetic susceptibility of YbN. The model, in which each crystal-field level couples to the band states with its own hybridization function, has previously been successfully applied without the ZZF approximation to explain the specific-heat structure at low temperatures. The ZZF approximation removes the spurious zero-temperature behavior of the parent noncrossing approximation for the susceptibility. Surprisingly, even at the low crystal-field degeneracy (N = 2) of YbN, the Shiba relation is very nearly satisfied. The appropriate experimental impurity susceptibility for comparison is extracted from the measurement by removing an empirical exchange interaction. The resultant Kondo temperature (T0 = 8.49 K) is consistent with previous specific-heat estimates (10-11 K), and the agreement with experiment is good. C1 SWISS FED INST TECHNOL,FESTKORPERPHYS LAB,CH-8093 ZURICH,SWITZERLAND. VIRGINIA POLYTECH INST & STATE UNIV,DEPT PHYS,BLACKSBURG,VA 24061. RP ZHOU, Y (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 24 TC 8 Z9 8 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 11071 EP 11075 DI 10.1103/PhysRevB.43.11071 PN B PG 5 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100032 ER PT J AU SUSMAN, S VOLIN, KJ MONTAGUE, DG PRICE, DL AF SUSMAN, S VOLIN, KJ MONTAGUE, DG PRICE, DL TI TEMPERATURE-DEPENDENCE OF THE 1ST SHARP DIFFRACTION PEAK IN VITREOUS SILICA SO PHYSICAL REVIEW B LA English DT Article ID INTERMEDIATE-RANGE ORDER; GLASS-TRANSITION; SELENIUM GLASSES; AS2SE3; SOLIDS; MOLTEN; GESE2 AB The temperature dependence of the first sharp diffraction peak (FSDP) in the neutron structure factor has been measured from room temperature to 1036-degrees-C. With increasing temperature, the FSDP decreases in amplitude in a normal fashion. This is in contrast to the anomalous temperature dependence of the FSDP that is typically observed in covalent oxide and chalcogenide glasses. The change in height of the FSDP with temperature is the result of a competition between an increase in the amplitude of thermal vibration at higher temperature and a diminished frustration at lower density. The normal behavior of the FSDP in vitreous silica is the consequence of an essentially zero thermal-expansion coefficient so that the effect due to thermal vibrations dominates. A structural rearrangements at elevated temperatures is also indicated. C1 WILLAMETTE UNIV,SALEM,OR. RP SUSMAN, S (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Price, David Long/A-8468-2013 NR 27 TC 63 Z9 63 U1 2 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 11076 EP 11081 DI 10.1103/PhysRevB.43.11076 PN B PG 6 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100033 ER PT J AU KIM, YT LAM, QH JEFFRIES, CD AF KIM, YT LAM, QH JEFFRIES, CD TI MAGNETIC-FIELD DEPENDENCE OF THE AC SUSCEPTIBILITY IN ANTIGRANULOCYTES YBA2CU3O7 - DATA AND MODELS SO PHYSICAL REVIEW B LA English DT Note ID HIGH-TC SUPERCONDUCTORS; HIGH-TEMPERATURE SUPERCONDUCTORS; CRITICAL-STATE MODEL; BA-CU-O; CRITICAL CURRENTS; NONLINEAR ELECTRODYNAMICS; POLYCRYSTALLINE YBA2CU3O7; CURRENT-DENSITY; BEAN MODEL; FLUX AB For a sintered rod of YBa2Cu3O7 at 78.3 K, detailed data are reported for the complicated dependence of the ac susceptibility approximately-chi = chi' - i-chi'' on applied ac and dc fields, ascribed to the inter- and intragranular components of the material. The intergranular data are understood in detail by a modified critical-state model, assuming a critical current density J(c)(H) approximately H-2. Approximately-chi(H(dc)) also displays hysteresis which is not readily explicable by this model. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV MAT & CHEM SCI,BERKELEY,CA 94720. NR 30 TC 33 Z9 33 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 11404 EP 11407 DI 10.1103/PhysRevB.43.11404 PN B PG 4 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100073 ER PT J AU LIU, LW KOUVEL, JS BRUN, TO AF LIU, LW KOUVEL, JS BRUN, TO TI ANISOTROPIC VORTEX CROSS-FLUX EFFECTS IN GRAIN-ORIENTED YBA2CU3O7 SO PHYSICAL REVIEW B LA English DT Note ID BA-CU-O; ROTATIONAL MAGNETIC PROCESSES; LOWER CRITICAL FIELDS; UNIAXIAL SUPERCONDUCTORS; SINGLE-CRYSTALS; LATTICES AB After cooling to 4.2 K in a field H(cool) parallel (or normal) to the c axis and then removing H(cool), the sample was subjected to an increasing field H normal (or parallel) to c and the longitudinal and transverse magnetizations relative to H were measured simultaneously. The vortex flux produced by H(cool) along c persists and inhibits the creation by H of vortex flux in the a-b plane. However, the creation of the latter does not require a threshold value of H. The vortex flux produced by H(cool) in the a-b plane diminishes rapidly with increasing H along c, and there are essentially no cross-flux effects. Thus, these effects are largely governed by the strength of the initial flux pinning, which is highly anisotropic. C1 LOS ALAMOS NATL LAB, P-LANSCE, LOS ALAMOS, NM 87545 USA. RP UNIV ILLINOIS, DEPT PHYS, CHICAGO, IL 60680 USA. NR 19 TC 8 Z9 8 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 11481 EP 11483 DI 10.1103/PhysRevB.43.11481 PN B PG 3 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100099 ER PT J AU PHILLIPS, NE FISHER, RA CASPARY, R AMATO, A RADOUSKY, HB PENG, JL ZHANG, L SHELTON, RN AF PHILLIPS, NE FISHER, RA CASPARY, R AMATO, A RADOUSKY, HB PENG, JL ZHANG, L SHELTON, RN TI MAGNETIC-ORDERING, HYPERFINE, AND LINEAR CONTRIBUTIONS TO THE LOW-TEMPERATURE SPECIFIC-HEAT OF (Y1-XPRX)BA2CU3O7-DELTA SO PHYSICAL REVIEW B LA English DT Note ID SINGLE-PHASE Y1-XPRXBA2CU3O7-DELTA; COPPER OXIDES; SUPERCONDUCTIVITY; PR; PRBA2CU3O7; HYBRIDIZATION; STATE AB Specific-heat measurements on (Y1-xPrx)Ba2Cu3O7-delta, for x = 0, 0.1, 0.2, 0.3, and 1, with 0.3 less-than-or-equal-to T less-than-or-equal-to 65 K, which include measurements in magnetic fields to 7 T, are reported. The combination of low-temperature and in-field data allows the separation of hyperfine and magnetic-ordering contributions from the low-temperature linear term, gamma-0T. The value of gamma-0, 200 mJ/molPrK2 for x = 0.1, 0.2, and 0.3, is substantially lower than that deduced from earlier measurements, but the determination of a cutoff temperature of approximately 50 K for this contribution adds to the appearance of heavy-fermion-like behavior. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616. RP PHILLIPS, NE (reprint author), LAWRENCE BERKELEY LAB,DIV MAT & CHEM SCI,BERKELEY,CA 94720, USA. RI Amato, Alex/H-7674-2013 OI Amato, Alex/0000-0001-9963-7498 NR 27 TC 33 Z9 33 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 11488 EP 11491 DI 10.1103/PhysRevB.43.11488 PN B PG 4 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100101 ER PT J AU XIANG, XD ZETTL, A VAREKA, WA CORKILL, JL BARBEE, TW COHEN, ML AF XIANG, XD ZETTL, A VAREKA, WA CORKILL, JL BARBEE, TW COHEN, ML TI EPITAXIAL INTERCALATION OF THE BI-SR-CA-CU-O SUPERCONDUCTOR SERIES SO PHYSICAL REVIEW B LA English DT Note ID TEMPERATURE; CHEMISTRY AB We have successfully intercalated epitaxial iodine spacers between BiO bilayers of the oxide superconductors Bi2Sr2CuOx (Bi 2:2:0:1), Bi2Sr2CaCu2Ox (Bi 2:2:1:2), and Bi2Sr2Ca2Cu3Ox (Bi 2:2:2:3), thereby forming new c-axis-expanded stage-I superconducting structures. Although the guest iodine layer expands each BiO bilayer by about 3.6 angstrom for all three compounds, the materials remain bulk superconductors with transition temperatures T(c) as high as 100 K. The respective shifts in T(c) upon intercalation of the different materials allow examination of the superconductivity mechanism in terms of the role of interplanar and intraplanar Cu-O coupling. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP XIANG, XD (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Xiang, Xiaodong/A-9445-2012; Zettl, Alex/O-4925-2016; Xiang, Xiaodong/A-5936-2017 OI Zettl, Alex/0000-0001-6330-136X; NR 13 TC 94 Z9 95 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1991 VL 43 IS 13 BP 11496 EP 11499 DI 10.1103/PhysRevB.43.11496 PN B PG 4 WC Physics, Condensed Matter SC Physics GA FL041 UT WOS:A1991FL04100103 ER PT J AU GULMEZ, E BEEDOE, S JAROSZEWICZ, T LING, AG WHITTEN, CA MCNAUGHTON, MW SANTANA, JR ADAMS, DL CUPPS, VR SIMON, AJ BARLETT, ML MCNAUGHTON, KH RILEY, PJ AF GULMEZ, E BEEDOE, S JAROSZEWICZ, T LING, AG WHITTEN, CA MCNAUGHTON, MW SANTANA, JR ADAMS, DL CUPPS, VR SIMON, AJ BARLETT, ML MCNAUGHTON, KH RILEY, PJ TI ABSOLUTE DIFFERENTIAL CROSS-SECTION MEASUREMENTS FOR PROTON-DEUTERON ELASTIC-SCATTERING AT 641.3 AND 792.7 MEV SO PHYSICAL REVIEW C LA English DT Article ID SPIN OBSERVABLES; IMPULSE APPROXIMATION; PHYSICS AB The absolute p-d elastic-scattering differential cross sections were measured at 641.3 and 792.7 MeV beam energies over a range of c.m. angles from approximately 35-degrees to approximately 115-degrees and approximately 35-degrees to approximately 140-degrees, respectively. The longitudinally polarized (L-type) proton beam produced by the Lamb-shift ion source at LAMPF was used. The beam intensity was measured to high accuracy (approximately 0.1%) by a scintillator-beam particle-counting system designed and developed prior to the experiment. Typical uncertainties in the absolute cross sections were about 2-3% total, somewhat larger at back angles. The present results were compared with the existing measurements and the controversy about the previous data at 800 MeV was resolved. The present data can be fit with a relativistic multiple-scattering theory which uses off-mass-shell extrapolations of the nucleon-nucleon amplitudes suggested by the structure of derivative meson-nucleon couplings. Relativistic-impulse-approximation calculations do not fit these data at either energy. C1 UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RICE UNIV,HOUSTON,TX 77251. RUTGERS STATE UNIV,NEW BRUNSWICK,NJ 08903. TEXAS A&M UNIV SYST,COLLEGE STN,TX 77843. UNIV TEXAS,AUSTIN,TX 78712. RP GULMEZ, E (reprint author), UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024, USA. RI Gulmez, Erhan/P-9518-2015 OI Gulmez, Erhan/0000-0002-6353-518X NR 30 TC 12 Z9 12 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1991 VL 43 IS 5 BP 2067 EP 2076 DI 10.1103/PhysRevC.43.2067 PG 10 WC Physics, Nuclear SC Physics GA FL895 UT WOS:A1991FL89500008 ER PT J AU FLANDERS, BS KELLY, JJ SEIFERT, H LOPIANO, D AAS, B AZIZI, A IGO, G WESTON, G WHITTEN, C WONG, A HYNES, MV MCCLELLAND, J BERTOZZI, W FINN, JM HYDEWRIGHT, CE LOURIE, RW NORUM, BE ULMER, P BERMAN, BL AF FLANDERS, BS KELLY, JJ SEIFERT, H LOPIANO, D AAS, B AZIZI, A IGO, G WESTON, G WHITTEN, C WONG, A HYNES, MV MCCLELLAND, J BERTOZZI, W FINN, JM HYDEWRIGHT, CE LOURIE, RW NORUM, BE ULMER, P BERMAN, BL TI EMPIRICAL DENSITY-DEPENDENT EFFECTIVE INTERACTION FOR NUCLEON-NUCLEUS SCATTERING AT 500 MEV SO PHYSICAL REVIEW C LA English DT Article ID 180 MEV PROTONS; 2-NUCLEON EFFECTIVE INTERACTION; FULL-FOLDING-MODEL; ELASTIC-SCATTERING; OPTICAL-MODEL; IMPULSE-APPROXIMATION; INELASTIC-SCATTERING; INTERMEDIATE ENERGIES; MICROSCOPIC DESCRIPTION; ELECTRON-SCATTERING AB We report new cross-section and analyzing-power data for the excitation by 498-MeV protons of all narrow normal-parity states of O-16 below 12.1-MeV excitation. In addition, spin-rotation measurements for elastic scattering and depolarization measurements for the 1(1)-, 2(1)+, and 3(1)- states of O-16 have been performed. These data are used in conjunction with existing data for Ca-40 to study medium corrections to the effective interaction for nucleon-nucleus scattering at 500 MeV. Systematic differences between the data and nonrelativistic impulse approximation calculations based upon either the free t matrix or a recent density-dependent effective interaction are interpreted within the framework of the local-density approximation. An empirical effective interaction has been constructed which parametrizes the density dependence of the medium modifications in a simple form amenable to phenomenological analysis of data. The parameters of the interaction are adjusted by fitting to data from many transitions simultaneously, including inelastic transitions sensitive to both the surface and the interior of the nucleus. We find that the empirical effective interaction provides a good description of both the fitted inelastic-scattering observables and elastic-scattering observables not included in the fit. Furthermore, we find that the empirical effective interaction fitted to inelastic-scattering data for O-16 provides an excellent description of both elastic- and inelastic-scattering data for Ca-40 at 500 MeV. The most significant difference between the empirical interaction and the theoretical interaction is that absorption is enhanced at higher density, contrary to expectations based upon Pauli blocking. We find also that the empirical interaction. has a stronger repulsive core than expected in nonrelativistic models of the effective interaction. Nevertheless, the optical potential are very similar to the Schrodinger-equivalent potentials from a relativistic impulse approximation model, showing that the empirical density dependence is comparable to the equivalent density dependence due to elimination of lower components from this relativistic model of the nucleon-nucleus interaction. These results are also compared with global optical potentials from Dirac phenomenology, which suggest even stronger repulsion in the real central interaction. C1 UNIV MARYLAND,DEPT PHYS & ASTRON,COLLEGE PK,MD 20742. UNIV CALIF LOS ANGELES,DEPT PHYS,LOS ANGELES,CA 90024. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. MIT,DEPT PHYS,CAMBRIDGE,MA 02139. MIT,NUCL SCI LAB,CAMBRIDGE,MA 02139. GEORGE WASHINGTON UNIV,DEPT PHYS,WASHINGTON,DC 20052. RP FLANDERS, BS (reprint author), AMERICAN UNIV,WASHINGTON,DC 20016, USA. NR 85 TC 26 Z9 26 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1991 VL 43 IS 5 BP 2103 EP 2126 DI 10.1103/PhysRevC.43.2103 PG 24 WC Physics, Nuclear SC Physics GA FL895 UT WOS:A1991FL89500012 ER PT J AU GAI, M RUSCEV, M BROMLEY, DA OLNESS, JW AF GAI, M RUSCEV, M BROMLEY, DA OLNESS, JW TI SPECTROSCOPY OF O-18 - C-14(LI-7,T-GAMMA)O-18 REACTION - OBSERVATION OF SELECTIVE ENHANCED E1 DEEXCITATIONS OF CLUSTER STATES SO PHYSICAL REVIEW C LA English DT Article ID ALGEBRAIC APPROACH; MOLECULAR-STATES; SINGLE-PARTICLE; BETA-DECAY; SCATTERING; FREEDOM; NUCLEUS AB The alpha-particle transfer reaction C-14(Li-7,t-gamma)O-18 was used to study gamma deexcitation modes in O-18 at a bombarding energy E(L) = 15 MeV. In this measurement 4X10(6) triton-gamma coincidence events were collected. All natural parity states up to the alpha-particle threshold at 6.227 MeV were studied. These data together with our previously published study of states above threshold, using the alpha + C-14 radiative capture reaction, provide relatively complete spectroscopic information on states in O-18 up to 8.3 MeV in excitation energy. Previously reported major gamma decay branching ratios were remeasured with higher accuracy and good agreement is found. Several new weak deexcitation modes are reported. Enhanced E1 decays, B(E1) congruent-to 10(-2) Weisskopf unit, were observed among the J-pi = 0(2)+, 1(1)-, 1(2)-, 2(3)-, and 3(3)- states, representing some of the most enhanced El's found in even-even nuclei. A strong empirical correlation between enhanced E1 decays and cluster structure is established. These enhanced B(E1)'s suggest a selective deexcitation mode in which the states involved preferentially decay to cluster states. The cluster states are strongly populated in cluster transfer reactions and weakly populated in (t,p) reactions. Predictions of the vibron cluster model are compared with our data. The presence in our data of contaminant lines from C-14(Li-7,alpha)N-17 allowed extraction of some information on N-17. C1 BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP GAI, M (reprint author), YALE UNIV,AW WRIGHT NUCL STRUCT LAB,NEW HAVEN,CT 06511, USA. NR 51 TC 28 Z9 29 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1991 VL 43 IS 5 BP 2127 EP 2139 DI 10.1103/PhysRevC.43.2127 PG 13 WC Physics, Nuclear SC Physics GA FL895 UT WOS:A1991FL89500013 ER PT J AU MANLEY, DM BERMAN, BL BERTOZZI, W BUTI, TN FINN, JM HERSMAN, FW HYDEWRIGHT, CE HYNES, MV KELLY, JJ KOVASH, MA KOWALSKI, S LOURIE, RW MURDOCK, B NORUM, BE PUGH, B SARGENT, CP MILLENER, DJ AF MANLEY, DM BERMAN, BL BERTOZZI, W BUTI, TN FINN, JM HERSMAN, FW HYDEWRIGHT, CE HYNES, MV KELLY, JJ KOVASH, MA KOWALSKI, S LOURIE, RW MURDOCK, B NORUM, BE PUGH, B SARGENT, CP MILLENER, DJ TI ELECTROEXCITATION OF NEGATIVE-PARITY STATES IN O-18 SO PHYSICAL REVIEW C LA English DT Article ID INELASTIC ELECTRON-SCATTERING; BETA-DECAY; NUCLEI; N-18; LIGHT AB Form-factor measurements in the momentum-transfer range 0.6 less-than-or-equal-to q less-than-or-equal-to 2.7 fm-1 are presented for the 1- levels in O-18 at 4.46, 6.20, 7.62, and 8.04 MeV, the 3- levels at 5.10, 6.40, and 8.29 MeV, and the 5- levels at 7.86 and 8.13 MeV. These are the first measurements of the 5- states by inelastic scattering and the first electron-scattering measurements of the higher 1- and 3- states. A Rosenbluth separation of the longitudinal and transverse form factors was performed by fitting the data with a phenomenological polynomial-times-Gaussian parametrization motivated by the form of theoretical form factors when harmonic-oscillator wave functions are used. Comparisons are made with structure models. The Coulomb form factors of several levels indicate the significance of small admixtures of 3 h-omega components in the negative-parity wave functions. C1 KENT STATE UNIV,CTR NUCL RES,KENT,OH 44242. GEORGE WASHINGTON UNIV,DEPT PHYS,WASHINGTON,DC 20052. MIT,DEPT PHYS,CAMBRIDGE,MA 02139. MIT,BIOCHEM & FOOD TECHNOL LAB,CAMBRIDGE,MA 02139. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP MANLEY, DM (reprint author), KENT STATE UNIV,DEPT PHYS,KENT,OH 44242, USA. NR 49 TC 16 Z9 16 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1991 VL 43 IS 5 BP 2147 EP 2161 DI 10.1103/PhysRevC.43.2147 PG 15 WC Physics, Nuclear SC Physics GA FL895 UT WOS:A1991FL89500015 ER PT J AU WOLF, A SCHOLTEN, O CASTEN, RF AF WOLF, A SCHOLTEN, O CASTEN, RF TI ANALYTIC FORMULA FOR B(E2) VALUES IN EVEN-EVEN NUCLEI WITH A-GREATER-THAN-60 SO PHYSICAL REVIEW C LA English DT Article ID INTERACTING BOSON MODEL AB An approximate analytic formula for calculating B(E2;2(1)+ --> 0(1)+) transition probabilities is proposed. We show that this formula reproduces quite accurately numerical calculations based on the interacting-boson model (IBM), and experimental data for a large number of nuclei from Zn to Pt, and in the actinide region, the largest discrepancies being of the order of 40%. The analytic relation is based on an IBM Hamiltonian, whose four parameters can be estimated using expressions given in the text. Since these expressions are based on a microscopic shell-model description, the formula only requires knowledge of the (N,Z) values of the isotope in question. C1 KERNFYS VERSNELLER INST,9747 AA GRONINGEN,NETHERLANDS. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP WOLF, A (reprint author), NUCL RES CTR NEGEV,IL-84190 BEER SHEVA,ISRAEL. NR 6 TC 6 Z9 6 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1991 VL 43 IS 5 BP 2279 EP 2283 DI 10.1103/PhysRevC.43.2279 PG 5 WC Physics, Nuclear SC Physics GA FL895 UT WOS:A1991FL89500027 ER PT J AU BRADY, FP FORD, TD NEEDHAM, GA ROMERO, JL SORENSON, DS CASTANEDA, CM DRUMMOND, JL HJORT, EL MCEACHERN, B KING, NSP MILLENER, DJ AF BRADY, FP FORD, TD NEEDHAM, GA ROMERO, JL SORENSON, DS CASTANEDA, CM DRUMMOND, JL HJORT, EL MCEACHERN, B KING, NSP MILLENER, DJ TI C-12(N,P)B-12 REACTION AT 56, 60, AND 65 MEV SO PHYSICAL REVIEW C LA English DT Article ID INELASTIC ELECTRON-SCATTERING; HIGH-MOMENTUM-TRANSFER; INTERMEDIATE ENERGIES; LIGHT-NUCLEI; N,P REACTION; ISOVECTOR TRANSITIONS; PROTON-SCATTERING; CROSS-SECTION; ANALOG STATES; P,N REACTIONS AB The C-12(n,p)B-12 reaction has been studied at 60 and 65 MeV. Cross sections for the 1+ ground state, the 2+ first excited state at 0.95 MeV, an unresolved pair of 2- and 4- states at 4.4 MeV, and the analogs of the giant electric dipole and spin-dipole resonances around 7.7 MeV have been extracted and compared with previous data at 56 MeV and with microscopic distorted-wave Born approximation calculations. The shapes of angular distributions out to q approximately 2 fm-1 are well reproduced by the calculations. A comparison of (n,p), (p,n), and (p,p') cross sections near 60 MeV is made, and a value for \J-sigma-tau\ (the volume integral of the central, spin-isospin part of the effective nucleon-nucleon interaction) is extracted. The magnitudes of cross sections for negative-parity states can be qualitatively understood when the loose binding of the sd-shell neutron in the final state and the effect of ground-state correlations on the dipole and spin-dipole strengths are taken into account. C1 UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP BRADY, FP (reprint author), UNIV CALIF DAVIS,CROCKER NUCL LAB,DAVIS,CA 95616, USA. NR 85 TC 47 Z9 47 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1991 VL 43 IS 5 BP 2284 EP 2302 DI 10.1103/PhysRevC.43.2284 PG 19 WC Physics, Nuclear SC Physics GA FL895 UT WOS:A1991FL89500028 ER PT J AU HEILBRONN, L GALONSKY, A GELBKE, CK LYNCH, WG MURAKAMI, T SACKETT, D SCHELIN, H TSANG, MB DEAK, F KISS, A SERES, Z KASAGI, J REMINGTON, BA AF HEILBRONN, L GALONSKY, A GELBKE, CK LYNCH, WG MURAKAMI, T SACKETT, D SCHELIN, H TSANG, MB DEAK, F KISS, A SERES, Z KASAGI, J REMINGTON, BA TI PRODUCTION OF NEUTRON-UNBOUND STATES IN INTERMEDIATE-MASS FRAGMENTS FROM N-14+AG REACTIONS AT E/A = 35 MEV SO PHYSICAL REVIEW C LA English DT Article ID HEAVY-ION COLLISIONS; NUCLEAR TEMPERATURE-MEASUREMENTS; AR-40 INDUCED REACTIONS; EXCITATION-ENERGY; LIGHT-NUCLEI; 2-PARTICLE CORRELATIONS; EMISSION TEMPERATURES; MOMENTUM WIDTHS; AU-197; DECAY AB The populations of neutron-unbound states and of bound states in intermediate-mass fragments have been measured at 15-degrees, 31-degrees, and 64-degrees from the N-14 + Ag reaction at E/A = 35 MeV. We did this for eleven neutron-unbound states in seven isotopes whose bound-state populations we were also able to measure. The data are identified in terms of the reaction mechanism producing them, which is either a deep-inelastic mechanism or a quasielastic mechanism. In order to test the assumption that the deep-inelastic data are produced from a thermal source, the unbound-state-bound-state population ratios of deep-inelastic fragments are compared to the predictions of a thermal sequential decay model. Most, but not all, of the deep-inelastic population ratios are fitted with model calculations that assume a source temperature between 2.5 and 3.5 MeV. In the case of C-13 we were able to measure four deep-inelastic populations, and in the case of B-12 we were able to measure three such populations. To further test the assumption of emission from a thermal source, attempts were made to fit all of the populations from each of these two isotopes with the sequential decay model using a single temperature. The deep-inelastic populations of C-13 were fitted with a single temperature between 2.5 and 5.0 MeV. The deep-inelastic populations of B-12 were not fitted with any temperature. There is enough of the deep-inelastic data that is not fitted with the predictions of a thermal model that the assumption of a thermal source for the production of deep-inelastic fragments may be incorrect, or there may be other effects present which alter the thermal properties of the data. The quasielastic populations in each B-12 and C-13 were also measured and could not be fitted with the model using a single temperature, which is consistent with the assumption of a non-thermal source of production for quasielastic fragments. The dependence of the unbound-state-bound-state population ratio on the fragment kinetic energy shows a difference between the quasielastic and deep-inelastic data. For quasielastic fragments whose mass is near the mass of the beam, the ratio decreases towards zero as the fragment velocity approaches the beam velocity. In contrast, the ratio for half-beam mass quasielastic fragments is constant or only slightly decreasing as the kinetic energy increases. The ratio for deep-inelastic fragments is approximately constant as a function of kinetic energy, independent of fragment mass. The amount of feeding from several neutron-unbound channels into bound states is measured and compared to the sequential decay model. The model successfully predicts the amount of feeding from most of the channels using a source temperature of 2.5 to 4.0 MeV. The effect of feeding both on spectral temperatures and on population temperatures is investigated. We conclude that the effect of feeding on both temperatures, as determined by model calculations, cannot account for the discrepancy in the values between the two. C1 MICHIGAN STATE UNIV, DEPT PHYS & ASTRON, E LANSING, MI 48824 USA. EOTVOS LORAND UNIV, DEPT ATOM PHYS, H-1088 BUDAPEST, HUNGARY. CENT RES INST PHYS, H-1525 BUDAPEST 114, HUNGARY. TOKYO INST TECHNOL, MEGURO KU, TOKYO 152, JAPAN. UNIV CALIF LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. KYOTO UNIV, DEPT PHYS, KYOTO 606, JAPAN. CTR TECN AEROESP, SAO JOSE CAMPOS, SP, BRAZIL. RP HEILBRONN, L (reprint author), MICHIGAN STATE UNIV, NATL SUPERCONDUCTING CYCLOTRON LAB, E LANSING, MI 48824 USA. RI Lynch, William/I-1447-2013; Heilbronn, Lawrence/J-6998-2013 OI Lynch, William/0000-0003-4503-176X; Heilbronn, Lawrence/0000-0002-8226-1057 NR 58 TC 7 Z9 7 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1991 VL 43 IS 5 BP 2318 EP 2335 DI 10.1103/PhysRevC.43.2318 PG 18 WC Physics, Nuclear SC Physics GA FL895 UT WOS:A1991FL89500031 ER PT J AU JIANG, J KEANE, D COGAR, J FAI, G HAYASHI, S HARTNACK, C STOCKER, H AF JIANG, J KEANE, D COGAR, J FAI, G HAYASHI, S HARTNACK, C STOCKER, H TI NUCLEAR TRANSPORT MODELS CAN REPRODUCE CHARGED-PARTICLE-INCLUSIVE MEASUREMENTS BUT ARE NOT STRONGLY CONSTRAINED BY THEM SO PHYSICAL REVIEW C LA English DT Article ID HEAVY-ION COLLISIONS; MOMENTUM-DEPENDENT INTERACTIONS; QUANTUM MOLECULAR-DYNAMICS; UEHLING-UHLENBECK THEORY; LIGHT FRAGMENTS; EQUATION; STATE; FLOW; DISTRIBUTIONS; MATTER AB Nuclear transport models are important tools for interpretation of many heavy-ion experiments and are essential in efforts to probe the nuclear equation of state. In order to fulfill these roles, the model predictions should at least agree with observed single-particle-inclusive momentum spectra; however, this agreement has recently been questioned. The present work compares the Vlasov-Uehling-Uhlenbeck model to data for mass-symmetric systems ranging from C-12 + C-12 to La-139 + La-139, and we find good agreement within experimental uncertainties at 0.4 A and 0.8 A GeV. For currently available data, these uncertainties are too large to permit effective nucleon-nucleon scattering cross sections in the nuclear medium to be extracted at a useful level of precision. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV FRANKFURT,INST THEORET PHYS,W-6000 FRANKFURT,GERMANY. RP JIANG, J (reprint author), KENT STATE UNIV,DEPT PHYS,KENT,OH 44242, USA. RI Stoecker, Horst/D-6173-2013 OI Stoecker, Horst/0000-0002-3282-3664 NR 36 TC 9 Z9 9 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1991 VL 43 IS 5 BP 2353 EP 2357 DI 10.1103/PhysRevC.43.2353 PG 5 WC Physics, Nuclear SC Physics GA FL895 UT WOS:A1991FL89500034 ER PT J AU WU, JS BOTTCHER, C STRAYER, MR SHAKIN, CM AF WU, JS BOTTCHER, C STRAYER, MR SHAKIN, CM TI INCOHERENT 2-PHOTON PRODUCTION OF THE HIGGS BOSON IN RELATIVISTIC HEAVY-ION COLLISIONS SO PHYSICAL REVIEW C LA English DT Article ID SCATTERING AB Cross sections for the incoherent production of the Higgs boson in ultrarelativistic heavy-ion collisions through two-photon processes are calculated by the direct Monte Carlo integration of Feynman diagrams incorporating nuclear-structure functions. C1 CUNY BROOKLYN COLL,DEPT PHYS,BROOKLYN,NY 11210. CUNY BROOKLYN COLL,CTR NUCL THEORY,BROOKLYN,NY 11210. RP WU, JS (reprint author), OAK RIDGE NATL LAB,CTR COMPUTAT INTENS PHYS,DIV PHYS,OAK RIDGE,TN 37831, USA. NR 18 TC 2 Z9 2 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1991 VL 43 IS 5 BP 2422 EP 2425 DI 10.1103/PhysRevC.43.2422 PG 4 WC Physics, Nuclear SC Physics GA FL895 UT WOS:A1991FL89500041 ER PT J AU BAKER, NJ KAHN, SA MURTAGH, MJ SAMIOS, NP TANAKA, M BALTAY, C HYATT, ER MANLY, S STEINER, R JACQUES, PF KALELKAR, M PLANO, RJ STAMER, PE AF BAKER, NJ KAHN, SA MURTAGH, MJ SAMIOS, NP TANAKA, M BALTAY, C HYATT, ER MANLY, S STEINER, R JACQUES, PF KALELKAR, M PLANO, RJ STAMER, PE TI MU-E+ DILEPTON PRODUCTION IN CHARGED-CURRENT NU-MU INTERACTIONS SO PHYSICAL REVIEW D LA English DT Article ID OPPOSITE-SIGN DIMUONS; 15-FOOT BUBBLE-CHAMBER; FERMILAB TEVATRON ENERGIES; SEMI-LEPTONIC DECAYS; NEUTRINO PRODUCTION; CHARMED BARYONS; CERN-SPS; ANTINEUTRINO INTERACTIONS; WIDEBAND NEUTRINO; EPSILON+ PAIRS AB The production of mu-e+ dileptons by muon neutrinos is studied in a high-statistics bubble-chamber experiment. The experiment consisted of exposing the Fermilab 15-ft bubble chamber filled with a heavy Ne-H-2 mix to a wideband neutrino beam. In a total sample of 146 700 +/- 11 700 charged-current interactions, 461 events with an e+(P(e)+ > 300 MeV/c) and a mu- are observed. The rate for mu-e+ dilepton production in measured to be (0.42 +/- 0.06)%. The energy dependence of this rate is presented. The kinematic distributions for the mu-e+ events are consistent with charm production and subsequent semileptonic decay. A total of 60 K(s)0 and 31 LAMBDA-0 decays were observed in the mu-e+ event sample. The measured rates for neutral-strange-particle production are 0.78 +/- 0.12 K0/KBAR0,s and 0.19 +/- 0.04 LAMBDA-0,s per mu-e+ event. Finally, rates for LAMBDA-c+, D0, and D+ production in charged-current nu-mu interactions are derived. They are found to be (4(-2)+10)%, (1.7(-0.7)+0.5)%, and (1.3(-0.5)+0.4)%, respectively. C1 SETON HALL UNIV,S ORANGE,NJ 07079. BROOKHAVEN NATL LAB,UPTON,NY 11973. COLUMBIA UNIV,NEW YORK,NY 10027. RUTGERS STATE UNIV,NEW BRUNSWICK,NJ 08903. NR 34 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1991 VL 43 IS 9 BP 2765 EP 2777 DI 10.1103/PhysRevD.43.2765 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK220 UT WOS:A1991FK22000003 ER PT J AU STRONGIN, B BOFILL, J FRIEDMAN, JI FUESS, S GOODMAN, MC KENDALL, HW KISTIAKOWSKY, V LYONS, T OSBORNE, LS PITT, R SCHNEEKLOTH, U TAYLOR, FE BOGERT, D KOIZUMI, G STUTTE, L ABOLINS, M BROCK, R COBAU, W HATCHER, R OWEN, D PERKINS, G TARTAGLIA, M WEERTS, H BELUSEVIC, R WALKER, JK WHITE, A WOMERSLEY, J AF STRONGIN, B BOFILL, J FRIEDMAN, JI FUESS, S GOODMAN, MC KENDALL, HW KISTIAKOWSKY, V LYONS, T OSBORNE, LS PITT, R SCHNEEKLOTH, U TAYLOR, FE BOGERT, D KOIZUMI, G STUTTE, L ABOLINS, M BROCK, R COBAU, W HATCHER, R OWEN, D PERKINS, G TARTAGLIA, M WEERTS, H BELUSEVIC, R WALKER, JK WHITE, A WOMERSLEY, J TI STUDY OF OPPOSITE-SIGN DIMUON PRODUCTION IN HIGH-ENERGY NEUTRINO-NUCLEON INTERACTIONS SO PHYSICAL REVIEW D LA English DT Article ID QUARK CHARGED CURRENTS; CROSS-SECTIONS; E+E ANNIHILATION; FERMILAB; PARAMETRIZATION; PARTICLES; TEVATRON; CHAMBER; MASSES; DECAY AB Results are presented of a study of opposite-sign dimuon events observed in a fine-grained neutrino detector exposed to the Fermilab Tevatron wide-band neutrino beam. A total of 300 background-corrected mu+mu- events induced by incident neutrinos and antineutrinos with energies up to 500 GeV were accumulated. The data were analyzed in terms of a model based on charm-quark production followed by semileptonic decay of the charmed meson. The Cabibbo-Kobayashi-Maskawa matrix terms were found to be \U(cd)\2 = 0.0378 +/- 0.0127 (stat)-0.0082(+0.0099) (syst), and kappa\U(cs)\2 = 0.391 +/- 0.076 (stat)-0.066(+0.097) (syst). The ratio of the strange to nonstrange sea in the nucleon, kappa = 2S/(UBAR + DBAR), was measured to be 0.407 +/- 0.075 (stat)-0.069(+0.103) (syst). C1 MIT,CAMBRIDGE,MA 02139. FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. MICHIGAN STATE UNIV,E LANSING,MI 48824. UNIV FLORIDA,GAINESVILLE,FL 32611. NR 45 TC 11 Z9 11 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1991 VL 43 IS 9 BP 2778 EP 2786 DI 10.1103/PhysRevD.43.2778 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK220 UT WOS:A1991FK22000004 ER PT J AU MORENO, G BROWN, CN COOPER, WE FINLEY, D HSIUNG, YB JONCKHEERE, AM JOSTLEIN, H KAPLAN, DM LEDERMAN, LM HEMMI, Y IMAI, K MIYAKE, K NAKAMURA, T SASAO, N TAMURA, N YOSHIDA, T MAKI, A SAKAI, Y GRAY, R LUK, KB RUTHERFOORD, JP STRAUB, PB WILLIAMS, RW YOUNG, KK ADAMS, MR GLASS, H JAFFE, D MCCARTHY, RL CRITTENDEN, JA SMITH, SR AF MORENO, G BROWN, CN COOPER, WE FINLEY, D HSIUNG, YB JONCKHEERE, AM JOSTLEIN, H KAPLAN, DM LEDERMAN, LM HEMMI, Y IMAI, K MIYAKE, K NAKAMURA, T SASAO, N TAMURA, N YOSHIDA, T MAKI, A SAKAI, Y GRAY, R LUK, KB RUTHERFOORD, JP STRAUB, PB WILLIAMS, RW YOUNG, KK ADAMS, MR GLASS, H JAFFE, D MCCARTHY, RL CRITTENDEN, JA SMITH, SR TI DIMUON PRODUCTION IN PROTON-COPPER COLLISIONS AT SQUARE-ROOT-S=38.8 GEV SO PHYSICAL REVIEW D LA English DT Article ID MUON-PAIR PRODUCTION; NUCLEUS COLLISIONS; HADRONIC PRODUCTION; TRANSVERSE-MOMENTUM; PRODUCTION DYNAMICS; CONTINUUM; PHYSICS; GAMMA; MODEL AB Experimental results on the production of dimuons by 800-GeV protons incident on a copper target are presented. The results include measurements of both the continuum of dimuons and the dimuon decays of the three lowest-mass UPSILON S states. A description of the apparatus, data acquisition, and analysis techniques is included. A comparison of the results with data taken at lower incident energies indicates a scaling behavior of the continuum dimuon yields. C1 FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. KYOTO UNIV,KYOTO 606,JAPAN. UNIV WASHINGTON,SEATTLE,WA 98195. SUNY STONY BROOK,STONY BROOK,NY 11794. KEK NAT LAB HIGH ENERGY PHYS,TSUKUBA,IBARAKI 305,JAPAN. COLUMBIA UNIV,NEVIS LABS,IRVINGTON,NY 10533. NR 47 TC 156 Z9 156 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1991 VL 43 IS 9 BP 2815 EP 2835 DI 10.1103/PhysRevD.43.2815 PG 21 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK220 UT WOS:A1991FK22000008 ER PT J AU RAMSEY, G SIVERS, D AF RAMSEY, G SIVERS, D TI VALENCE SPIN OBSERVABLES IN HARD-SCATTERING QCD AND THE MEASUREMENT OF THE GLUON SPIN-DENSITY SO PHYSICAL REVIEW D LA English DT Article ID PARTON MODEL; QUANTUM-CHROMODYNAMICS; PHOTON PRODUCTION; ANGULAR-MOMENTUM; POLARIZED BEAM; ASYMMETRIES; PROTON; FACTORIZATION; DISTRIBUTIONS; SYMMETRY AB To test the validity of the QCD-based hard-scattering model for spin-dependent measurements, it is useful to define observables which depend only on the valence-quark spin distributions. If theory proves an effective guide to these "valence" observables, the valence-quark contribution to other spin-dependent large-p(T) processes can be specified with similar accuracy. We can then formulate large-p(T) measurements which determine the gluon spin density in a polarized proton. C1 ARGONNE NATL LAB,DIV HIGH ENERGY PHYS,ARGONNE,IL 60439. RP RAMSEY, G (reprint author), LOYOLA UNIV,DEPT PHYS,CHICAGO,IL 60626, USA. NR 38 TC 23 Z9 23 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1991 VL 43 IS 9 BP 2861 EP 2870 DI 10.1103/PhysRevD.43.2861 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK220 UT WOS:A1991FK22000013 ER PT J AU SINGLETON, R AF SINGLETON, R TI SEMILEPTONIC BARYON DECAYS WITH A HEAVY QUARK SO PHYSICAL REVIEW D LA English DT Article ID WEAK MIXING ANGLES; LEPTONIC DECAY; MODEL; MESONS AB The semileptonic decay of spin-1/2 baryons is examined in the spectator-quark model, with special attention given to LAMBDA-b --> LAMBDA-c(e-upsilon) and OMEGA-b --> OMEGA-c(e-upsilon). The polarization of the virtual W and of the daughter baryon is also considered, along with the joint angular distribution between the charged lepton and the daughter-baryon polarization vector. The LAMBDA-b decays with about equal mixtures of transverse to longitudinal W polarization while the OMEGA-b decays with predominately longitudinal W polarization. These reactions are representative of two qualitatively different classes: decays involving baryons whose spectators are spin singlets and those whose spectators are spin triplets. RP SINGLETON, R (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 20 TC 47 Z9 47 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1991 VL 43 IS 9 BP 2939 EP 2950 DI 10.1103/PhysRevD.43.2939 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK220 UT WOS:A1991FK22000019 ER PT J AU HILL, CT LUTY, MA PASCHOS, EA AF HILL, CT LUTY, MA PASCHOS, EA TI ELECTROWEAK SYMMETRY-BREAKING BY 4TH-GENERATION CONDENSATES AND THE NEUTRINO SPECTRUM SO PHYSICAL REVIEW D LA English DT Article ID GROUP FIXED-POINTS; TOP-QUARK MASS; STANDARD MODEL; RENORMALIZATION; BOSONS AB We consider a new mechanism for dynamical symmetry breaking of the electroweak symmetries involving condensates of fourth-generation quarks and leptons. A dynamical generalization of the seesaw mechanism is proposed based upon the BCS theory in which a neutrino condensate gives rise to right-handed-neutrino Majorana masses and all associated spin-zero bosons are composite. The fourth-generation neutrino is naturally heavier than M(z)/2 and the scale of new physics is bounded above. The renormalization-group equations for the effective lagrangian of this model are derived and used to solve the model. Implications for neutrino masses are discussed. C1 UNIV CHICAGO,DEPT PHYS,CHICAGO,IL 60637. UNIV DORTMUND,INST PHYS,W-4600 DORTMUND 50,GERMANY. UNIV CHICAGO,ENRICO FERMI INST,CHICAGO,IL 60637. RP HILL, CT (reprint author), FERMI NATL ACCELERATOR LAB,POB 500,BATAVIA,IL 60510, USA. NR 31 TC 119 Z9 119 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1991 VL 43 IS 9 BP 3011 EP 3025 DI 10.1103/PhysRevD.43.3011 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK220 UT WOS:A1991FK22000026 ER PT J AU THOMPSON, KA RUTH, RD AF THOMPSON, KA RUTH, RD TI TRANSVERSE COUPLED-BUNCH INSTABILITIES IN DAMPING RINGS OF HIGH-ENERGY LINEAR COLLIDERS SO PHYSICAL REVIEW D LA English DT Article AB In this paper we present methods for studying and controlling transverse coupled-bunch instabilities. Our primary motivation is the study of damping rings for next-generation linear colliders in which many bunches are damped in the same ring simultaneously; however, the methods presented are also applicable to other situations. The theory developed here treates the motion of the bunch centroids, since the coherent dipole modes of coupled-bunch oscillation are expected to be strongly dominant. A formalism to obtain the n normal modes of oscillation of n bunches is developed. The imaginary part of the frequency of each normal mode determines its stability. However, not only the long-term stability of each oscillation mode, but also the transient behavior of the bunches just after injection, must be considered in damping rings. Two methods of studying the transient behavior are presented: (1) A Laplace-transform method, using the eigenmodes and corresponding eigen-frequencies found by the normal-modes formalism, and (2) computer tracking, using a localized-kick approximation. Examples are given for damping-ring designs appropriate to a linear collider of about 0.5-1.0 TeV center-of-mass energy. RP THOMPSON, KA (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 30 TC 8 Z9 8 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1991 VL 43 IS 9 BP 3049 EP 3062 DI 10.1103/PhysRevD.43.3049 PG 14 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK220 UT WOS:A1991FK22000030 ER PT J AU DEBOER, FWN WYATT, KD JUSTICE, M BISTIRLICH, JA BOSSINGHAM, RR CHACON, AD CROWE, KM VANDANTZIG, R GRAB, C KAMMEL, P LJUNGFELT, S MEYER, CA PETITJEAN, CA RASMUSSEN, JO STOYER, MA SULLIVAN, JP XU, YW AF DEBOER, FWN WYATT, KD JUSTICE, M BISTIRLICH, JA BOSSINGHAM, RR CHACON, AD CROWE, KM VANDANTZIG, R GRAB, C KAMMEL, P LJUNGFELT, S MEYER, CA PETITJEAN, CA RASMUSSEN, JO STOYER, MA SULLIVAN, JP XU, YW TI SEARCH FOR BOUND-STATES OF NEGATIVE PIONS AND NEUTRONS IN RELATIVISTIC HEAVY-ION REACTIONS SO PHYSICAL REVIEW D LA English DT Note ID COLLISIONS AB An experimental search for bound systems of pi-'s and neutrons (pineuts) was made in collisions of Ar-40 (1.8 A GeV) and La-139 (1.3 A GeV) projectiles on a U-238 target. Five candidate events survived the selection criteria but-in view of their marginal systematic systematic consistency-they are not taken as valid evidence for pineuts. Upper limits for production cross sections are derived for singly and doubly charged systems on the order of 4 x 10(-35) cm2/sr(MeV/c). C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. NATL INST NUCL PHYS & HIGH ENERGY PHYS,1098 SJ AMSTERDAM,NETHERLANDS. STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. AUSTRIAN ACAD SCI,A-1090 VIENNA,AUSTRIA. PAUL SCHERRER INST,CH-5232 VILLIGEN,SWITZERLAND. TEXAS A&M UNIV SYST,COLLEGE STN,TX 77843. INST ATOM ENERGY,BEIJING,PEOPLES R CHINA. RI Meyer, Curtis/L-3488-2014 OI Meyer, Curtis/0000-0001-7599-3973 NR 19 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1991 VL 43 IS 9 BP 3063 EP 3066 DI 10.1103/PhysRevD.43.3063 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK220 UT WOS:A1991FK22000031 ER PT J AU COGGESHALL, SV AF COGGESHALL, SV TI ANALYTIC SOLUTIONS OF HYDRODYNAMICS EQUATIONS SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Article ID COMPRESSION AB Many similarity solutions have been found for the equations of one-dimensional (1-D) hydrodynamics. These special combinations of variables allow the partial differential equations to be reduced to ordinary differential equations, which must then be solved to equations to be reduced to ordinary differential equations, which must then be solved to determine the physical solutions. Usually, these reduced ordinary differential equations are solved numerically. In some cases it is possible to solve these reduced equations analytically to obtain explicit solutions. In this work a collection of analytic solutions of the 1-D hydrodynamics equations is presented. These can be used for a variety of purposes, including (i) numerical benchmark problems, (ii) as a basis for analytic models, and (iii) to provide insight into more complicated solutions. RP COGGESHALL, SV (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 13 TC 6 Z9 6 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD MAY PY 1991 VL 3 IS 5 BP 757 EP 769 DI 10.1063/1.858008 PN 1 PG 13 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA FL370 UT WOS:A1991FL37000005 ER PT J AU FOIAS, C MANLEY, OP TEMAM, R AF FOIAS, C MANLEY, OP TEMAM, R TI APPROXIMATE INERTIAL MANIFOLDS AND EFFECTIVE VISCOSITY IN TURBULENT FLOWS SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Article ID TWO-DIMENSIONAL TURBULENCE; NAVIER-STOKES EQUATIONS AB The recently formulated concept of approximate inertial manifolds is exploited as a means for eliminating systematically the fine structure of the velocity field in two-dimensional flows. The resulting iterative procedure does not invoke any statistical properties of the solutions of Navier-Stokes equations. It leads to a modification of those equations, such that effective viscosity-like terms arise in a natural way. The rigorous mathematical considerations can be related to the corresponding physical concepts and intuition. The result leading to a numerical algorithm, essentially a nonlinear Galerkin method, provides a basis for large eddy simulation in which the subgrid model is derived from the properties of the Navier-Stokes equations, rather than from more or less justifiable ad hoc arguments. Some limited speculations concerning the expected results in three dimensions are also offered. C1 US DOE,GERMANTOWN,MD 20874. INDIANA UNIV,INST APPL MATH & SCI COMP,BLOOMINGTON,IN 47405. RP FOIAS, C (reprint author), INDIANA UNIV,DEPT MATH,BLOOMINGTON,IN 47405, USA. NR 26 TC 29 Z9 29 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD MAY PY 1991 VL 3 IS 5 BP 898 EP 911 DI 10.1063/1.858212 PN 1 PG 14 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA FL370 UT WOS:A1991FL37000017 ER PT J AU HOLM, DD KIMURA, Y AF HOLM, DD KIMURA, Y TI ZERO-HELICITY LAGRANGIAN KINEMATICS OF 3-DIMENSIONAL ADVECTION SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Article; Proceedings Paper CT INTERNATIONAL SYMP ON FLUID MECHANICS OF STIRRING AND MIXING CY AUG 20-24, 1990 CL UNIV CALIF SAN DIEGO, LA JOLLA, CA SP INT UNION THEORET & APPL MECH HO UNIV CALIF SAN DIEGO AB The toroidal-poloidal decomposition for divergenceless vector fields in three dimensions is used to classify incompressible steady velocity fields in three dimensions according to whether they have zero, or nonzero helicity, and whether they are integrable, or nonintegrable as dynamical systems. Linearized steady Rayleigh-Benard convection flows provide examples from each class. Computational techniques that preserve volume and helicity are developed and used to visualize the Lagrangian particle trajectories of three-dimensional advection for two Rayleigh-Benard flows having zero helicity in a periodic domain. C1 UNIV CALIF LOS ALAMOS SCI LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP HOLM, DD (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,MS B284,LOS ALAMOS,NM 87545, USA. OI Holm, Darryl D/0000-0001-6362-9912 NR 16 TC 29 Z9 29 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD MAY PY 1991 VL 3 IS 5 BP 1033 EP 1038 DI 10.1063/1.858083 PN 2 PG 6 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA FL372 UT WOS:A1991FL37200005 ER PT J AU KERSTEIN, AR AF KERSTEIN, AR TI LINEAR-EDDY MODELING OF TURBULENT TRANSPORT .5. GEOMETRY OF SCALAR INTERFACES SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Article; Proceedings Paper CT INTERNATIONAL SYMP ON FLUID MECHANICS OF STIRRING AND MIXING CY AUG 20-24, 1990 CL UNIV CALIF SAN DIEGO, LA JOLLA, CA SP INT UNION THEORET & APPL MECH HO UNIV CALIF SAN DIEGO ID FRACTAL DIMENSIONS; FLOWS AB Linear-eddy modeling is a method for simulating molecular mixing on a one-dimensional domain imbedded in a turbulent flow. This method is used to investigate the stochastic geometry of scalar interfaces. Simulated interfaces (i.e., scalar level sets) in a domain with a spatially uniform mean scalar gradient are found to exhibit fractal structure with respect to the absolute level, but not with respect to the level referenced to its local mean value. Implications regarding the interpretation of measured fractal properties are discussed. RP KERSTEIN, AR (reprint author), SANDIA NATL LABS,COMBUST RES FACIL,LIVERMORE,CA 94551, USA. NR 14 TC 21 Z9 23 U1 2 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD MAY PY 1991 VL 3 IS 5 BP 1110 EP 1114 DI 10.1063/1.858092 PN 2 PG 5 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA FL372 UT WOS:A1991FL37200014 ER PT J AU GLIMM, J ZHANG, Q SHARP, DH AF GLIMM, J ZHANG, Q SHARP, DH TI THE RENORMALIZATION-GROUP DYNAMICS OF CHAOTIC MIXING OF UNSTABLE INTERFACES SO PHYSICS OF FLUIDS A-FLUID DYNAMICS LA English DT Article; Proceedings Paper CT INTERNATIONAL SYMP ON FLUID MECHANICS OF STIRRING AND MIXING CY AUG 20-24, 1990 CL UNIV CALIF SAN DIEGO, LA JOLLA, CA SP INT UNION THEORET & APPL MECH HO UNIV CALIF SAN DIEGO ID RAYLEIGH-TAYLOR INSTABILITY; GROUP FIXED-POINT; VALIDATION AB The authors' determination of Rayleigh-Taylor fluid mixing rates is surveyed and placed in a broader scientific context. The significance of universality for this mixing rate is discussed. C1 UNIV CALIF LOS ALAMOS SCI LAB,INST THEORET,LOS ALAMOS,NM 87545. RP GLIMM, J (reprint author), SUNY STONY BROOK,DEPT APPL MATH,STONY BROOK,NY 11794, USA. OI ZHANG, Qiang /0000-0002-8659-5396 NR 11 TC 16 Z9 16 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8213 J9 PHYS FLUIDS A-FLUID PD MAY PY 1991 VL 3 IS 5 BP 1333 EP 1335 DI 10.1063/1.858061 PN 2 PG 3 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA FL372 UT WOS:A1991FL37200037 ER PT J AU MILLER, G AF MILLER, G TI EQUIVALENCE OF RESISTIVE EVOLUTION AND KINETIC DYNAMO MODELS FOR STOCHASTIC MAGNETIC-FIELDS SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID SURFACES; PLASMAS; PINCH AB The kinetic dynamo model of Jacobson and Moses [Phys. Rev. A 29, 3335 (1984)] and the resistive evolution model of Miller [Phys. Fluids 31, 1133 (1988)] are compared. Fourier analyzing the x dependence in slab geometry, both models reduce to an Ohm's law for Fourier components of the form j(k) = F(k) E(k)/eta, where j(k) and E(k) are the Fourier components of j parallel-to and E parallel-to, eta is the parallel resistivity, and F(k) is some function of k. The field line distribution function in the resistive evolution model can be chosen to make both models exactly equivalent, and implies that the characteristic field line length over which j parallel-to/B is constant is the electron mean-free path. The time scale for validity of both models is t > tau, where tau is the electron collision time. The stochastic current spreading implied by these models is in rough quantitative agreement with recent measurements. RP MILLER, G (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 12 TC 2 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD MAY PY 1991 VL 3 IS 5 BP 1182 EP 1185 DI 10.1063/1.859810 PG 4 WC Physics, Fluids & Plasmas SC Physics GA FK973 UT WOS:A1991FK97300008 ER PT J AU DEGROOT, JS CAMERON, SM MIZUNO, K ESTABROOK, KG DRAKE, RP KRUER, WL YOUNG, PE AF DEGROOT, JS CAMERON, SM MIZUNO, K ESTABROOK, KG DRAKE, RP KRUER, WL YOUNG, PE TI DENSITY AND TEMPERATURE PROFILES IN STRONGLY ABSORBING PLASMA WITH DISTRIBUTED ABSORPTION SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID HEAT-TRANSPORT; LASER; MODEL; GRADIENTS AB A model is presented of the spatial structure of a laser-heated, strongly absorbing, planar plasma. Inverse bremsstrahlung is very strong so that laser light absorption is not localized. Absorption is distributed over densities from well below critical to the critical density. It is shown that the spatial structure of the plasma is self-consistent with laser energy deposition and heat transport so measurement of the plasma structure can be used as diagnostic of absorption and transport. Nonphysical discontinuities in density and temperature at the critical surface that are predicted by previous local absorption models for strongly flux-limited heat transport are reduced. These jumps persist in the present model. It is shown that an improved flux-limited heat transport model, strongly limited in the underdense plasma and weakly limited in the overdense plasma, results in continuous density and temperature profiles. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,Y PROGRAM,LIVERMORE,CA 94550. UNIV CALIF DAVIS,PLASMA RES GRP,DAVIS,CA 95616. RP DEGROOT, JS (reprint author), UNIV CALIF DAVIS,DEPT APPL SCI,DAVIS,CA 95616, USA. RI Drake, R Paul/I-9218-2012 OI Drake, R Paul/0000-0002-5450-9844 NR 12 TC 14 Z9 14 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD MAY PY 1991 VL 3 IS 5 BP 1241 EP 1244 DI 10.1063/1.859817 PG 4 WC Physics, Fluids & Plasmas SC Physics GA FK973 UT WOS:A1991FK97300015 ER PT J AU YOUNG, PE BALDIS, HA ESTABROOK, KG AF YOUNG, PE BALDIS, HA ESTABROOK, KG TI SCATTERED-LIGHT NEAR THE LASER WAVELENGTH FROM NOVA 2-COLOR EXPERIMENTS SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID STIMULATED BRILLOUIN-SCATTERING; 2-PLASMON DECAY INSTABILITY; MU-M LASER; RAMAN-SCATTERING; FOIL TARGETS; PLASMAS; SIMULATION; SATURATION; BACKWARD AB A laser-produced plasma has been studied in which there is a peak plasma density between critical and quarter-critical for a substantial amount of time (approximately 400 psec). The behavior of temporally and spectrally resolved light near the wavelength of the interaction laser lambda-0, is compared to the decay with time of the peak plasma density inferred from three-halves harmonic emission and Raman scattered light. Evidence for seeding of stimulated Brillouin scattering by the two-plasmon decay instability is presented. C1 NATL RES COUNCIL CANADA,OTTAWA K1A 0R6,ONTARIO,CANADA. RP YOUNG, PE (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 25 TC 26 Z9 26 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD MAY PY 1991 VL 3 IS 5 BP 1245 EP 1249 DI 10.1063/1.859818 PG 5 WC Physics, Fluids & Plasmas SC Physics GA FK973 UT WOS:A1991FK97300016 ER PT J AU KONIGES, AE CROTINGER, JA DANNEVIK, WP CARNEVALE, GF DIAMOND, PH GANG, FY AF KONIGES, AE CROTINGER, JA DANNEVIK, WP CARNEVALE, GF DIAMOND, PH GANG, FY TI EQUILIBRIUM SPECTRA AND IMPLICATIONS FOR A 2-FIELD TURBULENCE MODEL SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Note ID MECHANICS; WAVES AB Analytic expressions are given for statistical mechanical equilibrium solutions of two-field turbulence model equations that are used in describing plasma drift waves and for passive scalar advection in a neutral fluid. These are compared with those previously proposed [Phys. Fluids B 1, 1331 (1989)], in particular regarding the role of the cross correlations between fields. Implications for two-point closure calculations are discussed. C1 UNIV CALIF SAN DIEGO,LA JOLLA,CA 92093. RP KONIGES, AE (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 16 TC 14 Z9 14 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD MAY PY 1991 VL 3 IS 5 BP 1297 EP 1299 DI 10.1063/1.859822 PG 3 WC Physics, Fluids & Plasmas SC Physics GA FK973 UT WOS:A1991FK97300021 ER PT J AU DRESDEN, M AF DRESDEN, M TI HEISENBERG, GOUDSMIT AND THE GERMAN A-BOMB SO PHYSICS TODAY LA English DT Letter RP DRESDEN, M (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94305, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD MAY PY 1991 VL 44 IS 5 BP 92 EP & PG 0 WC Physics, Multidisciplinary SC Physics GA FL724 UT WOS:A1991FL72400011 ER PT J AU TSCHAPLINSKI, TJ NORBY, RJ AF TSCHAPLINSKI, TJ NORBY, RJ TI PHYSIOLOGICAL INDICATORS OF NITROGEN RESPONSE IN A SHORT ROTATION SYCAMORE PLANTATION .1. CO-2 ASSIMILATION, PHOTOSYNTHETIC PIGMENTS AND SOLUBLE CARBOHYDRATES SO PHYSIOLOGIA PLANTARUM LA English DT Article DE AMERICAN SYCAMORE; CARBOHYDRATE; CHLOROPHYLL; NITROGEN; PHOTOSYNTHETIC RATE; PLATANUS-OCCIDENTALIS; WATER STRESS TOLERANCE ID STOMATAL CONDUCTANCE; INTENSIVE CULTURE; AMERICAN SYCAMORE; DOUGLAS-FIR; FERTILIZATION; ACCUMULATION; GROWTH AB American sycamore (Platanus occidentalis L.) seedlings were grown in the field under different urea-nitrogen fertilization regimes to identify physiological variables that characterize the growth response. Treatments included fertilization at the beginning of the growing season with 50, 150, 450 kg N ha-1, fertilization 3 times each at 37.5 kg N ha-1 and unfertilized control. The greatest aboveground biomass accumulation (3 x that of control) occurred in plots fertilized with 450 kg N ha-1, but nearly as much growth occurred when 37.5 kg N ha-1 was added periodically. Photosynthesis, chlorophyll concentrations and growth increased rapidly after the midseason application of 37.5 kg N ha-1 but not after the late-season application. Although nitrogen fertilization increased leaf area per plant, leaf nitrogen concentration did not differ between treatments. There was no evidence to indicate that fertilization extended the physiologically active season or increased susceptibility to drought or cold. Sycamore leaves accumulated sucrose and mannose in response to water stress in all treatments. Photosynthetic pigment concentrations and net photosynthetic rate were the most sensitive indicators of growth response to nitrogen fertilization in the first growing season. Careful timing (based on physiological indicators) of low level applications of nitrogen fertilizer can optimize growth. RP TSCHAPLINSKI, TJ (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,OAK RIDGE,TN 37831, USA. RI Norby, Richard/C-1773-2012; OI Norby, Richard/0000-0002-0238-9828; Tschaplinski, Timothy/0000-0002-9540-6622 NR 20 TC 13 Z9 13 U1 2 U2 5 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0031-9317 J9 PHYSIOL PLANTARUM JI Physiol. Plant. PD MAY PY 1991 VL 82 IS 1 BP 117 EP 126 PG 10 WC Plant Sciences SC Plant Sciences GA FR640 UT WOS:A1991FR64000017 ER PT J AU MOROZ, PE COLESTOCK, PL AF MOROZ, PE COLESTOCK, PL TI ELECTRON ABSORPTION OF FAST WAVES IN GLOBAL WAVE CALCULATIONS SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID ION-CYCLOTRON; TOKAMAK PLASMAS; PROPAGATION; GEOMETRY; FIELDS; RANGE AB The results of a theoretical study of fast wave electron absorption are presented. Proper expressions for the parallel component of the fast wave electric field E parallel-to and the electron absorption power, which can be used for global wave calculations, are derived. Electron absorption terms such as transit time magnetic pumping (TTMP), Landau damping and cross-term absorption are all shown to be of the same order of magnitude and should be taken into consideration. Wave equations are written in a form that incorporates electron absorption. Numerical results via the FASTWA code for the Phaedrus-T Tokamak illustrate the typical 3-D structure of the wave electric field and absorbed power, and the relation between different absorption mechanisms for a realistic Tokamak configuration. C1 PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543. RP MOROZ, PE (reprint author), UNIV WISCONSIN,DEPT NUCL ENGN & ENGN PHYS,MADISON,WI 53706, USA. NR 22 TC 9 Z9 9 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD MAY PY 1991 VL 33 IS 5 BP 417 EP 431 DI 10.1088/0741-3335/33/5/002 PG 15 WC Physics, Fluids & Plasmas SC Physics GA FN344 UT WOS:A1991FN34400002 ER PT J AU BOUILLARD, JX GIDASPOW, D LYCZKOWSKI, RW AF BOUILLARD, JX GIDASPOW, D LYCZKOWSKI, RW TI HYDRODYNAMICS OF FLUIDIZATION - FAST-BUBBLE SIMULATION IN A 2-DIMENSIONAL FLUIDIZED-BED SO POWDER TECHNOLOGY LA English DT Article ID JET AB The hydrodynamics of a 'fast bubble' in a two-dimensional rectangular fluidized bed is studied numerically. The fast bubble (which moves faster than the fluidizing velocity) is produced by injecting gas through a jet for a short time into a bed at minimum fluidization. The numerical computations are in good agreement with the classical theories of Davidson, Jackson, and Murray and with experimental data, thus enhancing confidence in the computer modeling of the hydrodynamics of fluidization. C1 IIT,DEPT CHEM ENGN,CHICAGO,IL 60616. RP BOUILLARD, JX (reprint author), ARGONNE NATL LAB,DIV ENERGY SYST,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 34 TC 17 Z9 17 U1 1 U2 3 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD MAY PY 1991 VL 66 IS 2 BP 107 EP 118 DI 10.1016/0032-5910(91)80092-W PG 12 WC Engineering, Chemical SC Engineering GA FU669 UT WOS:A1991FU66900001 ER PT J AU THOMPSON, LH WU, RW FELTON, JS AF THOMPSON, LH WU, RW FELTON, JS TI INTRODUCTION OF CYTOCHROME-P450IA2 METABOLIC CAPABILITY INTO CELL-LINES GENETICALLY MATCHED FOR DNA-REPAIR PROFICIENCY DEFICIENCY SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE CHO CELLS; MUTAGEN SENSITIVITY; BEEF MUTAGENS; MUTAGENESIS TESTING ID HAMSTER OVARY CELLS; CHO CELLS; MAMMALIAN-CELLS; COOKED-BEEF; MUTAGENIC COMPOUND; SALMONELLA MUTAGENICITY; CARCINOGENIC ARYLAMINES; ACTIVATION; GENE; CDNA AB We introduced into the CHO cell line the cDNA of the mouse cytochrome P3(450) (P450IA2) gene, which oxidizes aromatic amines. A cDNA clone of P3(450) was transfected into mutant UV5 cells, which is defective in nucleotide excision repair. Expression of the P3(450) cDNA was measured using 9000 x g supernatant (S9) fractions from CHO cells to evaluate Salmonella TA1538 mutagenicity with the mutagen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). The P3(450)-expressing clone UV5P3 was reverted to repair proficiency using ethyl methanesulfonate to obtain the UV-resistant clone 5P3R2, which maintained the same level of P3(450) protein activity as UV5P3. These genetically similar cell lines were compared for toxicity and mutation induction at the aprt locus. With 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (the most prevalent mutagen found in fried beef) the differential sensitivity due to repair deficiency/proficiency was almost-equal-to 40-fold, and with IQ there were smaller, but significant, differences in sensitivity. These genotoxic effects occurred at doses that were almost-equal-to 10 times lower than those that previously gave similar effects in S0-mediated assays. Thus, these cell lines should be valuable for genotoxicity analysis as well as important for assessing DNA repair when evaluating compounds that undergo metabolic activation. RP THOMPSON, LH (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,POB 5507,LIVERMORE,CA 94550, USA. FU NIEHS NIH HHS [IAG 224-01-ES-70158] NR 43 TC 34 Z9 34 U1 0 U2 0 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD MAY PY 1991 VL 88 IS 9 BP 3827 EP 3831 DI 10.1073/pnas.88.9.3827 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FK184 UT WOS:A1991FK18400066 PM 2023932 ER PT J AU CHEN, LC NEUBAUER, A KURISU, W WALDMAN, FM LJUNG, BM GOODSON, W GOLDMAN, ES MOORE, D BALAZS, M LIU, E MAYALL, BH SMITH, HS AF CHEN, LC NEUBAUER, A KURISU, W WALDMAN, FM LJUNG, BM GOODSON, W GOLDMAN, ES MOORE, D BALAZS, M LIU, E MAYALL, BH SMITH, HS TI LOSS OF HETEROZYGOSITY ON THE SHORT ARM OF CHROMOSOME-17 IS ASSOCIATED WITH HIGH PROLIFERATIVE CAPACITY AND DNA ANEUPLOIDY IN PRIMARY HUMAN BREAST-CANCER SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE TUMOR SUPPRESSOR GENE; PRIMARY BREAST CARCINOMA; P53 GENE; S-PHASE FRACTION ID RAS ONCOGENE; P53 GENE; MUTATIONS; CARCINOMA; LUNG; ADENOCARCINOMA; TRANSFORMATION; POLYMERASE AB Loss of heterozygosity (LOH) on the short arm of chromosome 17 (17p) was found in 27 of 52 (52%) previously untreated primary breast cancers. There was a significant correlation between this 17p allelic loss and two parameters associated with aggressive tumor behavior: high cellular proliferative fraction and DNA aneuploidy. These correlations with high cellular proliferative fraction and DNA aneuploidy were not found in tumors with LOH at nine other chromosome locations. The p53 gene, a putative tumor suppressor gene located at 17p13, was examined for aberrations to determine whether it is the target for the 17p LOH in breast cancer. Unlike other types of human cancer, there were no homozygous deletions or rearrangements of the p53 gene, and only 2 of 13 (15%) were mutated in the conserved region where mutational "hot spots" have been previously located. Therefore, we hypothesize that, in breast cancer, either loss or inactivation of gene(s) on chromosome 17p other than the p53 gene or a different mechanism of p53 gene inactivation may be responsible for the observed high labeling index and DNA aneuploidy associated with LOH at 17p. C1 PACIFIC PRESBYTERIAN MED CTR,GERALDINE BRUSH CANC RES INST,2330 CLAY ST,SAN FRANCISCO,CA 94115. UNIV CALIF SAN FRANCISCO,SCH MED,SAN FRANCISCO,CA 94143. UNIV N CAROLINA,LINEBERGER CANC RES CTR,CHAPEL HILL,NC 27514. UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,LIVERMORE,CA 94550. RI Liu, Edison/C-4141-2008 FU NCI NIH HHS [P01-CA44768] NR 38 TC 136 Z9 136 U1 2 U2 2 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD MAY PY 1991 VL 88 IS 9 BP 3847 EP 3851 DI 10.1073/pnas.88.9.3847 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FK184 UT WOS:A1991FK18400070 PM 1673792 ER PT J AU HAYASHI, F LIN, GY MATSUMOTO, H YAMAZAKI, A AF HAYASHI, F LIN, GY MATSUMOTO, H YAMAZAKI, A TI PHOSPHATIDYLINOSITOL-STIMULATED PHOSPHORYLATION OF AN INHIBITORY SUBUNIT OF CGMP PHOSPHODIESTERASE IN VERTEBRATE ROD PHOTORECEPTORS SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE SIGNAL TRANSDUCTION; TRANSDUCIN; OKADAIC ACID ID CYCLIC-GMP PHOSPHODIESTERASE; GTP-BINDING PROTEIN; LIGHT-INDUCED DEPHOSPHORYLATION; OUTER SEGMENTS; MEDIATED BREAKDOWN; GAMMA-SUBUNIT; TRANSDUCIN; MEMBRANE; PHOSPHATASES; NUCLEOTIDES AB An inhibitory subunit (P-gamma) of cGMP phosphodiesterase from vertebrate rod photoreceptors (frog, toad, and bovine) was phosphorylated by cytosolic protein kinase(s) derived from intact frog rod outer segments. The phosphorylation of frog P-gamma was stimulated by phosphatidylinositol but not by cAMP or cGMP. One- and two-dimensional gel electrophoresis revealed that 70-80% of P-gamma was phosphorylated with 1 mol of phosphate per frog P-gamma under optimal conditions. A peptide that derived from an active domain of bovine P-gamma was also phosphorylated. Phosphorylation of frog P-gamma was inhibited by addition of the peptide to the reaction mixture. Phosphorylation of frog P-gamma was also inhibited by addition of transducin subunits or active (P-gamma-less) cGMP phosphodiesterase. Okadaic acid, on the other hand, enhanced P-gamma phosphorylation, suggesting the presence of protein phosphatase(s) in the cytosolic fraction. These data suggest another mechanism for the regulation of cGMP phosphodiesterase in vertebrate rod photoreceptors. C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV LIFE SCI,CELLULAR & MOLEC BIOL GRP,LOS ALAMOS,NM 87545. UNIV OKLAHOMA,HLTH SCI CTR,COLL MED,DEPT BIOCHEM & MOLEC BIOL,OKLAHOMA CITY,OK 73190. FU NEI NIH HHS [EY07546, EY06595] NR 32 TC 36 Z9 37 U1 0 U2 0 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD MAY PY 1991 VL 88 IS 10 BP 4333 EP 4337 DI 10.1073/pnas.88.10.4333 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FM042 UT WOS:A1991FM04200057 PM 1852003 ER PT J AU SMIDT, CR UNKEFER, CJ HOUCK, DR RUCKER, RB AF SMIDT, CR UNKEFER, CJ HOUCK, DR RUCKER, RB TI INTESTINAL-ABSORPTION AND TISSUE DISTRIBUTION OF [C-14] PYRROLOQUINOLINE QUINONE IN MICE SO PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE LA English DT Article ID BOUND PYRROLOQUINOLINE QUINONE; RESONANCE RAMAN-SPECTROSCOPY; DOPAMINE BETA-HYDROXYLASE; PROSTHETIC GROUP; AMINE OXIDASE; LYSYL OXIDASE; COFACTOR; PQQ; IDENTIFICATION; DEHYDROGENASE AB Pyrroloquinoline quinone (PQQ) functions as a cofactor for prokaryotic oxido-reductases, such as methanol dehydrogenase and membrane-bound glucose dehydrogenase. In animals fed chemically defined diets, PQQ improves reproductive outcome and neonatal growth. Consequently, the present study was undertaken to determine the extent to which PQQ is absorbed by the intestine, its tissue distribution, and route of excretion. About 28-mu-g of PQQ (0.42-mu-Ci/mu-mol), labeled with C-14 derived from L-tyrosine, was administered orally to Swiss-Webster mice (18-20 g) to estimate absorption. PQQ was readily absorbed (62%, range 19-89%) in the lower intestine, and was excreted by the kidneys (81% of the absorbed dose) within 24 hr. The only tissues that retained significant amounts of [C-14]PQQ at 24 hr were skin and kidney. For kidney, it was assumed that retention of [C-14]PQQ represented primarily PQQ destined for excretion. For skin, the concentration of [C-14]PQQ increased from 0.3% of the absorbed dose at 6 hr to 1.3% at 24 hr. Furthermore, most of the [C-14]PQQ in blood (> 95%) was associated with the blood cell fraction, rather than plasma. C1 UNIV CALIF LOS ALAMOS SCI LAB,ISOTOPE & STRUCT CHEM GRP,LOS ALAMOS,NM 87545. UNIV CALIF DAVIS,DEPT NUTR,DAVIS,CA 95616. FU NHLBI NIH HHS [HL-15916]; NIADDK NIH HHS [AM-25358] NR 18 TC 32 Z9 34 U1 0 U2 7 PU BLACKWELL SCIENCE INC PI CAMBRIDGE PA 238 MAIN ST, CAMBRIDGE, MA 02142 SN 0037-9727 J9 P SOC EXP BIOL MED JI Proc. Soc. Exp. Biol. Med. PD MAY PY 1991 VL 197 IS 1 BP 27 EP 31 PG 5 WC Medicine, Research & Experimental SC Research & Experimental Medicine GA FK094 UT WOS:A1991FK09400004 PM 1850522 ER PT J AU CHRISTIAN, JE AF CHRISTIAN, JE TI UNDER STEEP ROOFING + ATTIC INSULATION AND RADIANT BARRIERS SO PROGRESSIVE ARCHITECTURE LA English DT Note RP CHRISTIAN, JE (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37830, USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU PENTON PUBL INC PI CLEVELAND PA 1100 SUPERIOR AVE, CLEVELAND, OH 44114 SN 0033-0752 J9 PROG ARCHIT JI Progress. Archit. PD MAY PY 1991 VL 72 IS 5 BP 54 EP 56 PG 3 WC Architecture SC Architecture GA FK375 UT WOS:A1991FK37500006 ER PT J AU BARTLETT, EJ BAROUCHE, F BRODIE, JD WOLKIN, A ANGRIST, B ROTROSEN, J WOLF, AP AF BARTLETT, EJ BAROUCHE, F BRODIE, JD WOLKIN, A ANGRIST, B ROTROSEN, J WOLF, AP TI STABILITY OF RESTING DEOXYGLUCOSE METABOLIC VALUES IN PET STUDIES OF SCHIZOPHRENIA SO PSYCHIATRY RESEARCH-NEUROIMAGING LA English DT Article DE POSITRON EMISSION TOMOGRAPHY (PET); DEOXYGLUCOSE; STABILITY; SCHIZOPHRENIA; METABOLISM ID POSITRON EMISSION TOMOGRAPHY; CEREBRAL GLUCOSE-UTILIZATION; REGIONAL BRAIN-FUNCTION; RATING-SCALE; HUMANS AB Positron emission tomography (PET) and the deoxyglucose method were used to determine the test-retest stability of regional cerebral glucose metabolism in 8 male schizophrenic patients and 11 normal control subjects, scanned twice under baseline (resting) conditions. Normal and schizophrenic subjects showed comparable stability of regional metabolism. When the regional values were scaled to compensate for the effects of changes in whole brain metabolism, the resulting mean regional changes were reduced to about 1-2% in both groups. This study demonstrates that the baseline resting state is an appropriate reference state for schizophrenic subjects in deoxyglucose PET experiments. C1 NYU MED CTR,DEPT PSYCHIAT,PET PROGRAM,550 1ST AVE,NEW YORK,NY 10016. VET ADM MED CTR,DEPT PSYCHIAT,NEW YORK,NY 10010. VET ADM MED CTR,PSYCHIAT SERV,NEW YORK,NY 10010. BROOKHAVEN NATL LAB,DEPT CHEM,CYCLOTRON PET PROGRAM,UPTON,NY 11973. FU NIMH NIH HHS [MH-35976]; NINDS NIH HHS [NS-15638] NR 21 TC 37 Z9 37 U1 0 U2 1 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0925-4927 J9 PSYCHIAT RES-NEUROIM JI Psychiatry Res. Neuroimaging PD MAY PY 1991 VL 40 IS 1 BP 11 EP 20 DI 10.1016/0925-4927(91)90025-L PG 10 WC Clinical Neurology; Neuroimaging; Psychiatry SC Neurosciences & Neurology; Psychiatry GA FU831 UT WOS:A1991FU83100002 PM 1946838 ER PT J AU EDMONDS, J AF EDMONDS, J TI UNCERTAINTIES IN ENERGY SCENARIOS AND THEIR CONSEQUENCES FOR CO-2 EMISSIONS SO PURE AND APPLIED CHEMISTRY LA English DT Article ID TROPICAL FORESTS RP EDMONDS, J (reprint author), PACIFIC NW LAB, WASHINGTON, DC USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0033-4545 J9 PURE APPL CHEM JI Pure Appl. Chem. PD MAY PY 1991 VL 63 IS 5 BP 778 EP 782 PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA FJ389 UT WOS:A1991FJ38900015 ER PT J AU FRY, RJM AF FRY, RJM TI RADIATION CARCINOGENESIS IN THE WHOLE-BODY SYSTEM SO RADIATION RESEARCH LA English DT Editorial Material RP FRY, RJM (reprint author), OAK RIDGE NATL LAB,DIV BIOL,POB 2009,OAK RIDGE,TN 37831, USA. NR 0 TC 6 Z9 6 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAY PY 1991 VL 126 IS 2 BP 157 EP 161 DI 10.2307/3577814 PG 5 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA FK351 UT WOS:A1991FK35100007 PM 1673796 ER PT J AU CORNFORTH, MN GOODWIN, EH AF CORNFORTH, MN GOODWIN, EH TI TRANSMISSION OF RADIATION-INDUCED ACENTRIC CHROMOSOMAL FRAGMENTS TO MICRONUCLEI IN NORMAL HUMAN FIBROBLASTS SO RADIATION RESEARCH LA English DT Article ID HUMAN-LYMPHOCYTES; BONE-MARROW; KINETOCHORE; ABERRATIONS; ANEUPLOIDY; ASSAY; IDENTIFICATION; IRRADIATION; INDUCTION; SEQUENCE RP CORNFORTH, MN (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV LIFE SCI,CELLULAR & MOLEC BIOL GRP,LOS ALAMOS,NM 87545, USA. FU NCI NIH HHS [CA45141] NR 29 TC 46 Z9 48 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAY PY 1991 VL 126 IS 2 BP 210 EP 217 DI 10.2307/3577820 PG 8 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA FK351 UT WOS:A1991FK35100013 PM 2023991 ER PT J AU MURLEY, JS GRDINA, DJ MEECHAN, PJ AF MURLEY, JS GRDINA, DJ MEECHAN, PJ TI ACCUMULATION OF CHO CELLS IN G2 PHASE FOLLOWING EXPOSURE TO WR-1065 SO RADIATION RESEARCH LA English DT Article ID DNA STRAND BREAKS; V79 CELLS; 2-<(AMINOPROPYL)AMINO> ETHANETHIOL; CHEMICAL-COMPOUNDS; ULTRAVIOLET-LIGHT; MOLECULAR-WEIGHT; ESCHERICHIA-COLI; WR-2721; RADIOTHERAPY; CHEMOTHERAPY C1 ARGONNE NATL LAB,DIV BIOL,ARGONNE,IL 60439. ARGONNE NATL LAB,DIV MED RES,ARGONNE,IL 60439. RP MURLEY, JS (reprint author), NO ILLINOIS UNIV,DEPT BIOL SCI,DE KALB,IL 60115, USA. FU NCI NIH HHS [CA-37435]; NCRR NIH HHS [S07 RR07176] NR 32 TC 12 Z9 12 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAY PY 1991 VL 126 IS 2 BP 223 EP 228 DI 10.2307/3577822 PG 6 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA FK351 UT WOS:A1991FK35100015 PM 2023993 ER PT J AU CZYZEWSKI, Z JOY, DC AF CZYZEWSKI, Z JOY, DC TI CALCULATION OF SECONDARY-ELECTRON PRODUCTION USING A DIFFUSION MATRIX SO SCANNING LA English DT Article ID MONTE-CARLO CALCULATIONS; BACKSCATTERED ELECTRONS; SURFACE-TOPOGRAPHIES; RECONSTRUCTION; SCATTERING; MICROSCOPY; SIGNAL AB The diffusion matrix model proposed by Desai and Reimer (1990) has been investigated. After some modifications it appeared to be a powerful tool for rapid determination of the SE and BSE signals from two-dimensional surface topographies. Results for low atomic number specimens show good agreement between experimental and theoretical data. C1 WARSAW POLYTECH INST,INST ELECTRON TECHNOL,PL-00661 WARSAW,POLAND. OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN. RP CZYZEWSKI, Z (reprint author), UNIV TENNESSEE,DEPT ZOOL,EM FACIL,F239 WALTERS LIFE SCI BLDG,KNOXVILLE,TN 37996, USA. NR 13 TC 3 Z9 3 U1 0 U2 2 PU FAMS INC PI MAHWAH PA BOX 832, MAHWAH, NJ 07430 SN 0161-0457 J9 SCANNING JI Scanning PD MAY-JUN PY 1991 VL 13 IS 3 BP 227 EP 232 PG 6 WC Instruments & Instrumentation; Microscopy SC Instruments & Instrumentation; Microscopy GA FQ633 UT WOS:A1991FQ63300003 ER PT J AU TRAVIS, CC HATTEMERFREY, HA AF TRAVIS, CC HATTEMERFREY, HA TI HUMAN EXPOSURE TO DIOXIN SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article ID ISOMER-SPECIFIC DETERMINATION; AQUATIC MODEL ECOSYSTEM; DIBENZO-PARA-DIOXINS; CHLORINATED DIOXINS; RISK ASSESSMENT; PLANT FOLIAGE; AMBIENT AIR; 2,3,7,8-TETRACHLORODIBENZO-PARA-DIOXIN TCDD; POLYCHLORINATED DIBENZOFURANS; ENVIRONMENTAL-SAMPLES AB Because 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is the most potent chemical carcinogen evaluated by the U.S. Environmental Protection Agency (EPA), many people fear that exposure to even small amounts of TCDD could lead to serious health effects. Ambient measurements confirm that environmental TCDD contamination is widespread. The public is concerned about TCDD exposure from such diverse sources as municipal solid waste incinerators, pulp and paper mills, and contaminated fish and soil. This paper evaluates several critical issues including: (i) the extent of background contamination; (ii) accumulation in the food chain and the potential for human exposure from ingesting contaminated food items; (iii) the magnitude of TCDD emissions into the U.S. environment, and the relative contribution of various known TCDD sources to the total TCDD load; and (iv) setting environmental standards for TCDD. C1 LEE WAN & ASSOCIATES,OAK RIDGE,TN 37830. RP TRAVIS, CC (reprint author), OAK RIDGE NATL LAB,DIV HLTH & SAFETY RES,OFF RISK ANAL,POB 2008,BLDG 4500S,OAK RIDGE,TN 37831, USA. NR 113 TC 101 Z9 103 U1 1 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD MAY 1 PY 1991 VL 104 IS 1-2 BP 97 EP 127 DI 10.1016/0048-9697(91)90010-C PG 31 WC Environmental Sciences SC Environmental Sciences & Ecology GA FP878 UT WOS:A1991FP87800009 PM 1871593 ER PT J AU YANG, HS JIN, P DALDER, E MUKHERJEE, AK AF YANG, HS JIN, P DALDER, E MUKHERJEE, AK TI SUPERPLASTICITY IN A TI3AL-BASE ALLOY STABILIZED BY NB, V AND MO SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article ID TI-6AL-4V ALLOY; BEHAVIOR; MICROSTRUCTURES C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP YANG, HS (reprint author), UNIV CALIF DAVIS,DEPT MECH AERONAUT & MAT ENGN,DAVIS,CA 95616, USA. NR 14 TC 41 Z9 49 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0956-716X J9 SCRIPTA METALL MATER JI Scr. Metall. Materialia PD MAY PY 1991 VL 25 IS 5 BP 1223 EP 1228 DI 10.1016/0956-716X(91)90532-6 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA FJ690 UT WOS:A1991FJ69000045 ER PT J AU VEMURI, V AF VEMURI, V TI SIMULATION OF A DISTRIBUTED-PROCESSING SYSTEM - A CASE-STUDY SO SIMULATION LA English DT Article DE DISTRIBUTED; PROCESSING SYSTEMS; REAL-TIME; SYSTEM PERFORMANCE AB Many modern computer systems require a continual monitoring of their projected performance from the design phase until the system becomes operational. This means forecasting system performance with very little data available during the early design phase and continually updating the forecast as the design matures. While designing computer systems with time-crital performance constraints, the timing requirements are hard to meet if crucial decisions are not made at the design stage. Experience with the Over The Horizon--Backscatter radar data processing project is used as an example to illustrate how these decisions are made using a variety of techniques such as benchmark testing, paper-pencil analysis, and simulation. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP VEMURI, V (reprint author), UNIV CALIFORNIA DAVIS,DEPT APPL SCI,LIVERMORE,CA 94550, USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SIMULATION COUNCILS INC PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92117 SN 0037-5497 J9 SIMULATION JI Simulation PD MAY PY 1991 VL 56 IS 5 BP 302 EP 315 DI 10.1177/003754979105600506 PG 14 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering SC Computer Science GA FN210 UT WOS:A1991FN21000004 ER PT J AU EARY, LE RAI, D AF EARY, LE RAI, D TI CHROMATE REDUCTION BY SUBSURFACE SOILS UNDER ACIDIC CONDITIONS SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID OXIDATION-REDUCTION; HEXAVALENT CHROMIUM; NATURAL-WATERS; KINETICS; BEHAVIOR; IRON; TRANSFORMATIONS; 25-DEGREES-C; DISSOLUTION; ADSORPTION AB Experimental studies of Cr(VI) reduction by five subsoils (Holston-Cloudland, Kenoma, Cecil-Paculet, Watson-Alvira, and Ocala) were conducted to determine whether the Fe(II) contained in soil minerals could cause Cr(VI) to be reduced to Cr(III) and precipitated as hydroxide solids. All of the subsoils contained small amounts of Fe(II) and organic matter, but only the acidic subsoils (1:2 soil pH = 4.2-4.3) caused Cr(VI) reduction at their natural pH values. Rates of Cr(VI) reduction by four of the subsoils increased with a decrease in pH below 4.0. Consideration of available kinetic information, coincidental timing of Cr(VI) disappearance and Fe(II) appearance in solution, and observed reaction stoichiometries indicate that Cr(VI) reduction by Fe(II) species is of equivalent importance as reduction by organic material under acidic conditions. Chromium(VI) reduction in the acidic subsoils resulted in the precipitation of (Fe,Cr)(OH)3(am), depending on the solution pH. The amount of NH2OH.HCl-extractable Fe in the acidic subsoils was found to be useful for determining the mole fraction of Fe(III) in the (Fe,Cr)(OH)3(am) solid solution, allowing prediction of Cr(III) concentrations in acidic solutions to within a logarithmic unit of those observed in experimental soil-water suspensions. RP EARY, LE (reprint author), PACIFIC NW LAB, CTR EARTH & ENVIRONM SCI, POB 999, RICHLAND, WA 99352 USA. NR 36 TC 114 Z9 125 U1 3 U2 23 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 0361-5995 EI 1435-0661 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD MAY-JUN PY 1991 VL 55 IS 3 BP 676 EP 683 PG 8 WC Soil Science SC Agriculture GA FZ634 UT WOS:A1991FZ63400007 ER PT J AU TSCHAPLINSKI, TJ JOHNSON, DW NORBY, RJ TODD, DE AF TSCHAPLINSKI, TJ JOHNSON, DW NORBY, RJ TODD, DE TI BIOMASS AND SOIL-NITROGEN RELATIONSHIPS OF A ONE-YEAR-OLD SYCAMORE PLANTATION SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID INTENSIVE CULTURE; FERTILIZATION AB Maximum efficiency in biomass production in short-rotation woody crops requires a level of N fertilization that achieves a balance between maximum growth and minimum NO3- leaching into groundwater. The effects of urea-N fertilizer applied under various timing regimes were investigated in a plantation of American sycamore (Platanus occidentalis L.), and different aspects of optimum fertilization were explored. A plantation of sycamore was established at Oak Ridge, TN, typically a N-poor area. Nitrogen treatments consisted of differing schedules of urea application, including trees fertilized at the beginning of the growing season with 0, 50, 150, and 450 kg N/ha, and trees fertilized periodically (three times during the growing season) at 37.5 kg N/ha. Fertilization effects on stem and leaf biomass, leaf nutrient concentration, soil N characteristics, including available N, mineralizable N, nitrification potential, and NO3- leaching loss were determined. The greatest aboveground biomass accumulation (three times greater than that of unfertilized controls) was obtained with 450 kg N/ha, but with greater NO3- leaching. Nearly as much biomass was obtained with almost no NO3- leaching when much less N was added either early in the season (150 kg N/ha) or in periodic applications (37.5 kg N/ha three times). The rapid decline to control levels of soil available N in all treatments, and the results of the aerobic incubations, indicate high nitrification potential at the site. The results suggest that periodic, low N fertilization may be optimal on sites with a high nitrification potential, and that the lower rates tested minimize NO3- contamination of groundwater. C1 OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. BIOL SCI CTR,DESERT RES INST,RENO,NV 89506. RI Norby, Richard/C-1773-2012; OI Norby, Richard/0000-0002-0238-9828; Tschaplinski, Timothy/0000-0002-9540-6622 NR 21 TC 15 Z9 15 U1 0 U2 4 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD MAY-JUN PY 1991 VL 55 IS 3 BP 841 EP 847 PG 7 WC Soil Science SC Agriculture GA FZ634 UT WOS:A1991FZ63400037 ER PT J AU CISZEK, TF AF CISZEK, TF TI SILICON FLOAT-ZONED CRYSTAL-GROWTH FOR HIGH MINORITY CHARGE-CARRIER LIFETIME MATERIAL APPLICATIONS SO SOLAR CELLS LA English DT Article ID AUGER-RECOMBINATION; SOLAR-CELLS; DENSITY AB The performance of a number of electronic devices such as solar cells, power devices, and transistors is strongly influenced by minority charge-carrier lifetimes in the semi-conductor material. The conditions for float-zone growth of silicon crystals for these devices can be adjusted to achieve charge-carrier lifetimes as long as 20 ms. Low impurity levels are of course necessary, and the material must be free of dislocations and grain boundaries. Microdefects such as swirl defects (A- or B-type) and frozen-in defects are also carrier recombination centers, and thus must be controlled during crystal growth. The type and density of defects can be altered by changing the growth conditions. Long minority charge-carrier lifetimes are achieved at moderately high growth rates and low thermal gradients during crystal growth. RP SOLAR ENERGY RES INST, GOLDEN, CO 80401 USA. NR 27 TC 2 Z9 2 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 5 EP 13 DI 10.1016/0379-6787(91)90032-K PG 9 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500002 ER PT J AU CRANDALL, RS TSUO, YS XU, Y MAHAN, AH WILLIAMSON, DL AF CRANDALL, RS TSUO, YS XU, Y MAHAN, AH WILLIAMSON, DL TI RECENT AMORPHOUS-SILICON RESEARCH RESULTS AT THE SOLAR-ENERGY-RESEARCH-INSTITUTE SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO AB Measurements of transport properties and microstructure of hydrogenated amorphous silicon-germanium alloys are reported. Emphasis is placed on the effects of hydrogen dilution of the source gas. The transport properties include photoconductivity, ambipolar diffusion length; the structure was determined from small-angle X-ray scattering. C1 COLORADO SCH MINES,GOLDEN,CO 80401. RP CRANDALL, RS (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 5 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 15 EP 19 DI 10.1016/0379-6787(91)90033-L PG 5 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500003 ER PT J AU TUTTLE, JR ALBIN, DS NOUFI, R AF TUTTLE, JR ALBIN, DS NOUFI, R TI THOUGHTS ON THE MICROSTRUCTURE OF POLYCRYSTALLINE THIN-FILM CUINSE2 AND ITS IMPACT ON MATERIAL AND DEVICE PERFORMANCE SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO ID CDS/CULNSE2 SOLAR-CELL; SEMICONDUCTORS; CUGASE2 AB The microstructure and morphology of polycrystalline thin film CuInSe2 were studied extensively in the compositional range 17-32 at.% Cu. The grain size varied with substrate temperature, copper content, and in variable ways with substrate type, and ranged in size from 0.1 to 5.0-mu-m. The morphology of copper-rich films appeared additionally to depend on the resident nucleation and growth of the Cu2-delta-Se binary compound. A microstructural model of polycrystalline thin film CuInSe2 is presented and suggests that the intergranular microstructure is dominated by the compositional and substrate temperature dependence of Cu2-delta-Se precipitation at grain boundaries and free surfaces. The intragranular microstructure of the near-stoichiometric grain is a phase-separated mixture of ordered chalcopyrite and disordered sphalerite, with Cu(x)Se(x = 0.5, 1.0, 1.5, 2.0) minority phase inclusions. Off-stoichiometric copper-poor film compositions additionally contain isolated grains of the chalcopyrite-variant ordered-vacancy compound CuIn2Se3.5. The potential ramifications of the microstructure on the device performance include a reduction in the photo-active volume, carrier transport across phase boundaries, and dependence of transport parameters on the crystallite size. RP TUTTLE, JR (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 26 TC 95 Z9 95 U1 1 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 21 EP 38 DI 10.1016/0379-6787(91)90034-M PG 18 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500004 ER PT J AU ALBIN, DS MOONEY, GD CARAPELLA, J DUDA, A TUTTLE, J MATSON, R NOUFI, R AF ALBIN, DS MOONEY, GD CARAPELLA, J DUDA, A TUTTLE, J MATSON, R NOUFI, R TI THE PHASE-BEHAVIOR OF EVAPORATED COPPER AND INDIUM PRECURSORS FOR SELENIZATION SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO ID SOLAR-CELLS; FILMS; CUINSE2 AB In this paper we discuss the phase behavior and microstructure of sequentially evaporated indium-on-copper layer stacks deposited onto molybdenum-coated glass substrates. It was determined that both equilibrium and non-equilibrium phases can exist depending on processing. Indium evaporated onto copper, without intentional substrate heating and no subsequent annealing, resulted in the formation of the CuIn (JCPDS card 35-1100) alloy phase and an unreported f.c.c. phase of undetermined composition. Auger spectrometry and X-ray diffraction strongly suggested this to be a new Cu-In alloy. Indium evaporated onto copper with substrate heating at 200-degrees-C followed by uncontrolled cooling to room temperature strongly favored the formation of Cu11In9 in addition to the two phases previously mentioned. The lack of elemental indium in both cases, the presence of which is expected from phase diagram analysis, was attributed to kinetic limitations. Annealing of Cu/In layer stacks for 1 h at 200-degrees-C immediately following indium deposition promoted the formation of elemental indium and Cu11In9 while simultaneously reducing the concentration of both CuIn and the new f.c.c. alloy phase. The implications of these observations are discussed with regard to future selenization experiments. RP ALBIN, DS (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 12 TC 17 Z9 17 U1 0 U2 6 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 41 EP 46 DI 10.1016/0379-6787(91)90035-N PG 6 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500005 ER PT J AU ALBIN, DS MOONEY, GD DUDA, A TUTTLE, J MATSON, R NOUFI, R AF ALBIN, DS MOONEY, GD DUDA, A TUTTLE, J MATSON, R NOUFI, R TI ENHANCED GRAIN-GROWTH IN POLYCRYSTALLINE CUINSE2 USING RAPID THERMAL-PROCESSING SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO AB Rapid thermal processing of precursor small-grained (less than or equal to 1-mu-m) CuInSe2 thin films can result in enhanced grain growth on the order of 100-mu-m under certain processing conditions. Crystal growth was accompanied by large increases (X 10) in the X-ray diffraction intensity of the (112) peak, indicating near-perfect crystal growth in the [221] direction. Single-crystal quality was verified by selected-area electron channeling. However, at present, this effect occurs in conjunction with excessive void and pinhole formation between single-crystal platelets. These voids are often decorated with relatively selenium-deficient phases. RP ALBIN, DS (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 18 TC 11 Z9 12 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 47 EP 52 DI 10.1016/0379-6787(91)90036-O PG 6 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500006 ER PT J AU CAHEN, D NOUFI, R AF CAHEN, D NOUFI, R TI SURFACE PASSIVATION OF POLYCRYSTALLINE, CHALCOGENIDE BASED PHOTOVOLTAIC CELLS SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO ID 2-STAGE PROCESS; SOLAR-CELLS; THIN-FILMS; CUINSE2; OXYGEN AB We present a summary of our defect chemical microscopic model for the effect that annealing in air or oxygen has on CuInSe2 and CdTe-based polycrystalline thin film solar cells and explain its generalization to other chalcogenide-based semiconductor devices. The summary includes a hypothesis for specific O2 (molecule) and surface interaction From the point of view of device performance, the model provides a specific chemical explanation for the conclusions obtained from device analyses that the performance of the present generation of polycrystalline cells of this type is mainly limited by recombination at grain surfaces and boundaries. C1 WEIZMANN INST SCI,DEPT STRUCT CHEM,IL-76100 REHOVOT,ISRAEL. SOLAR ENERGY RES INST,GOLDEN,CO 80401. RP CAHEN, D (reprint author), WEIZMANN INST SCI,CTR ENERGY RES,IL-76100 REHOVOT,ISRAEL. NR 33 TC 49 Z9 49 U1 1 U2 14 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 53 EP 59 DI 10.1016/0379-6787(91)90037-P PG 7 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500007 ER PT J AU MOONEY, GD HERMANN, AM TUTTLE, JR ALBIN, DS NOUFI, R AF MOONEY, GD HERMANN, AM TUTTLE, JR ALBIN, DS NOUFI, R TI THE FORMATION OF CUINSE2 THIN-FILMS BY RAPID THERMAL-PROCESSING SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO ID CULNSE2 AB Formation of polycrystalline thin film CuInSe2 was achieved by the rapid thermal processing of vacuum-deposited copper, indium, and selenium. Films were fabricated and characterized in three composition regions: copper-poor (approximately 20 at.% Cu), stoichiometric (25 at.% Cu) and copper-rich (approximately 28 at.% Cu). Characterization results including X-ray diffraction analysis, electron probe for microanalysis, scanning electron microscopy, and optical reflection and transmission measurements are presented. The results show that nearly single-phase material has been formed from co-deposited precursors with a post-deposition annealing time of less than 2 min. The films have smooth morphologies amenable for photovoltaic device fabrication, optical absorption coefficients in the high 10(4) cm-1 range, and an optical band gap of 1.0 eV. C1 SOLAR ENERGY RES INST,GOLDEN,CO 80401. RP MOONEY, GD (reprint author), UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309, USA. NR 13 TC 9 Z9 9 U1 0 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 69 EP 77 DI 10.1016/0379-6787(91)90039-R PG 9 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500009 ER PT J AU MOSKOWITZ, PD FTHENAKIS, VM AF MOSKOWITZ, PD FTHENAKIS, VM TI ENVIRONMENTAL, HEALTH AND SAFETY ISSUES ASSOCIATED WITH THE MANUFACTURE AND USE OF II-VI-PHOTOVOLTAIC DEVICES SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO AB Federal and state agencies have classified cadmium and selenium compounds as hazardous. Consequently, facilities using these materials are subject to various regulations and guidelines developed by these agencies. The intent of these guidelines is to protect worker and public health from accidental and routine chemical exposures. In this context, the agencies provide specific limits on public and occupational exposures, and generalized guidance on methods or approaches for attaining such limits. This paper gives background information on the toxicology and pharmacology of cadmium and selenium compounds. and reviews several newly proposed or adopted Federal and state regulations which can affect photovoltaic manufacturing facility operations using these and other chemicals. RP MOSKOWITZ, PD (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,BIOMED & ENVIRONM ASSESSMENT GRP,UPTON,NY 11973, USA. NR 20 TC 11 Z9 11 U1 4 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 89 EP 99 DI 10.1016/0379-6787(91)90041-M PG 11 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500011 ER PT J AU ABOUELFOTOUH, FA MOUTINHO, H BAKRY, A COUTTS, TJ KAZMERSKI, LL AF ABOUELFOTOUH, FA MOUTINHO, H BAKRY, A COUTTS, TJ KAZMERSKI, LL TI CHARACTERIZATION OF THE DEFECT LEVELS IN COPPER INDIUM DISELENIDE SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO ID CUINSE2 SINGLE-CRYSTALS; INTERFACE PROPERTIES AB High-resolution photoluminescence (PL) measurements were carried out at 10 K to identify the energy levels associated with the various defect states dominating the semiconductor CuInSe2 (CIS). PL measurements were taken on the bare surfaces of both thin film and single-crystal (polished and cleaved) samples and through a (Cd,Zn)S window layer deposited by thermal co-evaporation onto the CIS absorber surface. A complete energy band diagram is proposed which identifies the origin of the 12 intrinsic defect states expected in this material. The effects of surface and heat treatments, used in device fabrication processing, on the existence and generation of defect states (deep and shallow) are identified and correlated with the device performance. The inferior single-crystal device performance is correlated with presence of a high density of process-generated radiative surface recombination states and trap levels. RP ABOUELFOTOUH, FA (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 11 TC 65 Z9 65 U1 1 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 151 EP 160 DI 10.1016/0379-6787(91)90048-T PG 10 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500018 ER PT J AU AHRENKIEL, RK KEYES, BM DUNLAVY, DJ AF AHRENKIEL, RK KEYES, BM DUNLAVY, DJ TI NONLINEAR RECOMBINATION PROCESSES IN PHOTOVOLTAIC SEMICONDUCTORS SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO ID MINORITY-CARRIER LIFETIME; EPITAXIAL GAAS; (AL,GA)AS EPILAYERS; LASERS; ABSORPTION; INTERFACE AB The single-lifetime model is commonly used to describe recombination in photovoltaic materials. Here we describe two non-linear processes which affect the applicability of that model. Photon recycling is observed in direct band gap materials such as GaAs. This self-absorption and secondary emission of photons makes the effective radiative lifetime a function of device geometry. The saturation of recombination centers by minority carriers produces light intensity dependent lifetimes when the former are present. These effects need to be considered in device design and modeling. RP AHRENKIEL, RK (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 26 TC 8 Z9 8 U1 0 U2 5 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 163 EP 176 DI 10.1016/0379-6787(91)90049-U PG 14 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500019 ER PT J AU LUFT, W STAFFORD, B VONROEDERN, B AF LUFT, W STAFFORD, B VONROEDERN, B TI NEEDS OF THE AMORPHOUS-SILICON PROGRAM WITH RESPECT TO STABILIZED MODULE PERFORMANCE SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO ID POTENTIAL FLUCTUATIONS; DEFECTS; SI AB Amorphous silicon technology offers an avenue for low-cost thin film photovoltaic applications. The performance of amorphous silicon-based solar cells is limited by light-induced degradation. Inadequate description of the electronic phenomena in these materials and devices hampers resolution of this problem. We are posing questions which should stimulate researchers to develop better descriptions for device performance and better microscopic models for defect sites. The issue of Staebler-Wronski degradation should not be addressed separately from initial performance, but research should focus on material and device properties in the stabilized state. The main focus of a-Si:H research sponsored by the U.S. Department of Energy will be improvement of stabilized performance, which we anticipate to accomplish through focused development of optimized multijunction device structures, combined with an improved understanding of materials. RP LUFT, W (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 22 TC 1 Z9 1 U1 1 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 195 EP 205 DI 10.1016/0379-6787(91)90051-P PG 11 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500021 ER PT J AU WANG, K HAN, D SILVER, M BRANZ, HM AF WANG, K HAN, D SILVER, M BRANZ, HM TI ELECTROLUMINESCENCE STUDIES OF RECOMBINATION IN HYDROGENATED AMORPHOUS-SILICON P-I-N DEVICES SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO AB We present experimental data on the voltage and temperature (80 < T < 300 K) dependence of electroluminescence and forward bias current in hydrogenated amorphous silicon (a-Si:H) p-i-n structures. Since electrons and holes are injected from opposite sides of the sample, we are able to probe non-geminate radiative and non-radiative recombination processes in the intrinsic layer of actual device structures. We find that the effective generation rate in the electroluminescence experiment is proportional to the square of the applied voltage because the radiative recombination rate is proportional to the double-injection electron density. A simple model of electron recombination rates explains the data. The non-radiative recombination rate was found to be temperature dependent, but the radiative recombination rate is temperature independent. C1 SOLAR ENERGY RES INST,GOLDEN,CO 80401. RP WANG, K (reprint author), UNIV N CAROLINA,DEPT PHYS & ASTRON,CHAPEL HILL,NC 27599, USA. NR 6 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 219 EP 225 DI 10.1016/0379-6787(91)90053-R PG 7 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500023 ER PT J AU MCMAHON, TJ AF MCMAHON, TJ TI DEFECT EQUILIBRATION AND METASTABILITY IN LOW-SPIN-DENSITY AMORPHOUS HYDROGENATED SILICON SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO ID SI-H; TEMPERATURE AB Electron spin resonance was used to characterize concentrations of thermal equilibrium defects from room temperature to 280-degrees-C in a 60-mu-m thick hydrogenated amorphous silicon film. A defect formation energy of 0.35 eV was found in material with 1 X 10(15) cm-3 spins at 190-degrees-C. Annealing of defects quenched in from 250-degrees-C revealed an activation energy of 2.2 eV. Annealings at 150-degrees-C of defects quenched in at 250-degrees-C and 190-degrees-C were compared; the additional defects introduced at the higher temperature annealed 10 times faster, supporting a model in which metastable states with higher formation energies have smaller annealing activation energies. Light-induced defects are described in terms of a very "high-temperature" distribution similar to that which might be quenched in as a result of kT almost-equal-to 0.5 eV. RP MCMAHON, TJ (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 17 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 235 EP 243 DI 10.1016/0379-6787(91)90055-T PG 9 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500025 ER PT J AU WANLASS, MW WARD, JS EMERY, KA GESSERT, TA OSTERWALD, CR COUTTS, TJ AF WANLASS, MW WARD, JS EMERY, KA GESSERT, TA OSTERWALD, CR COUTTS, TJ TI HIGH-PERFORMANCE CONCENTRATOR TANDEM SOLAR-CELLS BASED ON IR-SENSITIVE BOTTOM CELLS SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO AB Computer simulations of two-junction, concentrator tandem solar cell performance show that IR-sensitive bottom cells are required to achieve high efficiencies. Based on this conclusion, two novel concentrator tandem designs are under investigation: (1) a mechanically stacked, four-terminal GaAs/GaInAsP (0.95 eV) tandem, and (2) a monolithic, lattice-matched, three-terminal InP/GaInAs tandem. In preliminary experiments, terrestrial concentrator efficiencies exceeding 30% have been achieved with each of the above tandem designs. Methods for improving the efficiency of each tandem type are discussed. RP WANLASS, MW (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 9 TC 25 Z9 25 U1 1 U2 7 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 363 EP 371 DI 10.1016/0379-6787(91)90069-2 PG 9 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500039 ER PT J AU SOPORI, BL AF SOPORI, BL TI SILICON SOLAR-CELL MATERIALS RESEARCH - CURRENT PROGRESS AND FUTURE-NEEDS SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO AB This paper presents a brief review of the research being carried out under the crystalline silicon materials research program. The primary emphasis of this program is the development of processes for post-growth quality enhancement of low-cost silicon substrates. The various electronic mechanisms that can be exploited for material quality enhancement are summarized. Major research results of the current program and some important aspects of future research are identified. RP SOPORI, BL (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 10 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 373 EP 381 DI 10.1016/0379-6787(91)90070-6 PG 9 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500040 ER PT J AU GESSERT, TA LI, X COUTTS, TJ AF GESSERT, TA LI, X COUTTS, TJ TI PRACTICAL GUIDELINES FOR GRID METALLIZATION IN PHOTOVOLTAIC SOLAR-CELL RESEARCH SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO AB During the research stage, many photovoltaic solar cells suffer substantial power loss due to the use of non-optimum top contact grids. The very nature of solar cell research implies that many cell parameters will be in a continual state of change and thus the grid will seldom be truly optimized. However, several things can be done to ensure that a solar cell grid will perform well even if the parameters vary. In this paper, critical parameters for solar cell grid modeling and design are identified and discussed. Particular attention is paid to the manner in which process aspects affect these parameters and the subsequent power loss of the grid. Finally, practical guidelines are presented, the use of which can minimize the effect of process variation. RP GESSERT, TA (reprint author), SOLAR ENERGY RES INST,GOLDEN,CO 80401, USA. NR 8 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 459 EP 472 DI 10.1016/0379-6787(91)90078-4 PG 14 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500048 ER PT J AU ABOUELFOTOUH, FA HORNER, GS COUTTS, TJ WANLASS, MW AF ABOUELFOTOUH, FA HORNER, GS COUTTS, TJ WANLASS, MW TI BROAD-BAND SPECTROSCOPIC ELLIPSOMETRY FOR THE CHARACTERIZATION OF PHOTOVOLTAIC MATERIALS SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO AB The availability of commercial spectroscopic ellipsometers (SE) has been restricted to the UV-visible range from 250-900 run. Although this is useful for many applications, it must be extended to the near IR region (up to 1700 nm) for the study of the optical behavior of most photovoltaic materials. This paper discusses the development of a broad band (300-1700 run) SE which has been used to measure the optical characteristics of various materials. Among these are the polycrystalline thin film materials, CuInSe2 and CdTe (for which single crystal samples have also been investigated), and materials for high efficiency cascade solar cells including InP, InGaAs and InGaAsP. Most of these data are not presently available over such a wide spectral range. Experimentally, a rotating polarizer-fixed analyzer ellipsometer with an a.c. detection system has been developed for accurate measurement of psi and DELTA, the relevant ellipsometric parameters, in the near IR. This approach has certain advantages over the rotating analyzer-fixed polarizer systems including reduced sensitivity to room light. The analytical methods include the use of a specially developed computer modeling program which gives psi and DELTA for a given set of values related to the film thickness (which may be finite or zero) and to the optical properties of the substrate. RP ABOUELFOTOUH, FA (reprint author), SOLAR ENERGY RES INST,1617 COLE BD,GOLDEN,CO 80401, USA. NR 6 TC 12 Z9 12 U1 0 U2 5 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 473 EP 485 DI 10.1016/0379-6787(91)90079-5 PG 13 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500049 ER PT J AU RIORDAN, C HULSTROM, R CANNON, T MYERS, D AF RIORDAN, C HULSTROM, R CANNON, T MYERS, D TI SOLAR-RADIATION RESEARCH FOR PHOTOVOLTAIC APPLICATIONS SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO AB This paper gives an overview of the fiscal year 1990 research activities and results under the Solar Radiation Research Task of the Photovoltaic Advanced Research and Development Project at the Solar Energy Research Institute. The activities under this task include developing and applying measurement techniques, instrumentation, and data analysis and modeling to understand and quantify the response of photovoltaic devices to variations in broad-band and spectral solar radiation. RP RIORDAN, C (reprint author), SOLAR ENERGY RES INST,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 18 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 489 EP 500 DI 10.1016/0379-6787(91)90080-9 PG 12 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500050 ER PT J AU KURTZ, SR OLSON, JM FAINE, P AF KURTZ, SR OLSON, JM FAINE, P TI THE DIFFERENCE BETWEEN STANDARD AND AVERAGE EFFICIENCIES OF MULTIJUNCTION COMPARED WITH SINGLE-JUNCTION CONCENTRATOR CELLS SO SOLAR CELLS LA English DT Article; Proceedings Paper CT 10TH PHOTOVOLTAIC RESEARCH AND DEVELOPMENT PROJECT REVIEW MEETING CY OCT 23-25, 1990 CL LAKEWOOD, CO ID CASCADE SOLAR-CELL; 2-JUNCTION; MODEL AB The theoretical performances of ideal single- and multijunction cells are compared at 100 X concentration under a range of cloudless-sky conditions. The sensitivities of device performance to cell temperature and spectral variations are shown to depend on the number of junctions (one, two or three), the way in which the junctions are connected (series, parallel or independent), and the band gaps of the devices. The average performances of all of the multijunction devices surpass that of a single-junction GaAs device, but the inconsistency in performance of some of the multijunction devices is significant for large variations in cell temperature and incident spectrum. The choice of band gap and connection scheme is more important than the number of junctions in determining the consistency of device performance. RP KURTZ, SR (reprint author), SOLAR ENERGY RES INST,GOLDEN,CO 80401, USA. NR 21 TC 24 Z9 24 U1 0 U2 5 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6787 J9 SOL CELLS PD MAY PY 1991 VL 30 IS 1-4 BP 501 EP 513 DI 10.1016/0379-6787(91)90081-Y PG 13 WC Energy & Fuels SC Energy & Fuels GA FQ725 UT WOS:A1991FQ72500051 ER PT J AU BORDET, P COX, DE ESPINOSA, GP HODEAU, JL MAREZIO, M AF BORDET, P COX, DE ESPINOSA, GP HODEAU, JL MAREZIO, M TI SYNCHROTRON X-RAY-POWDER DIFFRACTION STUDY OF THE PHASE-1' COMPOUND - SNLA3RH4SN12 SO SOLID STATE COMMUNICATIONS LA English DT Article ID STRUCTURAL DISTORTION; TERNARY; STANNIDES AB The structure of the phase I' compound Sn(1)La3Rh4Sn(2)12 has been investigated by Rietveld refinement of synchrotron x-ray powder diffraction data. It has cubic symmetry, space group I4(1)32, with a = 19.492 angstrom, and is a superstructure of that of phase I stannides with aI' = 2 aI, due to the distortion of the Sn(1)Sn(2)12 icosahedra related to a charge transfer from Sn(2) toward Sn(1) atoms. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP BORDET, P (reprint author), UJF,CNRS,CRISTALLOG LAB,166X,F-38042 GRENOBLE,FRANCE. NR 14 TC 16 Z9 16 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD MAY PY 1991 VL 78 IS 5 BP 359 EP 366 DI 10.1016/0038-1098(91)90684-N PG 8 WC Physics, Condensed Matter SC Physics GA FL906 UT WOS:A1991FL90600009 ER PT J AU LU, ZW WEI, SH ZUNGER, A FERREIRA, LG AF LU, ZW WEI, SH ZUNGER, A FERREIRA, LG TI GROUND-STATE STRUCTURES OF INTERMETALLIC COMPOUNDS - A 1ST-PRINCIPLES ISING-MODEL SO SOLID STATE COMMUNICATIONS LA English DT Article ID TRANSITION-METAL ALLOYS; PHASE-DIAGRAMS AB Predictions of the equilibrium crystal structure of simple compounds, e.g., within first-principles total energy methods are usually carried out by searching for the lowest energy among a small number, O(10), of intuitively selected candidate structures. We show how calculations of the total energies of O(10) structures can be used instead to define a first-principles, multi-spin Ising Hamiltonian, whose ground state structures on a fixed lattice can be systematically searched using lattice theory methods. This is illustrated for the intermetallic compounds CuAu, CuPd, CuPt, and CuRh, for which the correct ground states are identified out of more than 65,000 possible structures. C1 UNIV SAO PAULO, INST FIS, SAO PAULO, BRAZIL. RP SOLAR ENERGY RES INST, GOLDEN, CO 80401 USA. RI Zunger, Alex/A-6733-2013 NR 20 TC 16 Z9 16 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1098 EI 1879-2766 J9 SOLID STATE COMMUN JI Solid State Commun. PD MAY PY 1991 VL 78 IS 7 BP 583 EP 588 DI 10.1016/0038-1098(91)90382-6 PG 6 WC Physics, Condensed Matter SC Physics GA FP664 UT WOS:A1991FP66400003 ER PT J AU GARY, SP AF GARY, SP TI ELECTROMAGNETIC ION ION INSTABILITIES AND THEIR CONSEQUENCES IN SPACE PLASMAS - A REVIEW SO SPACE SCIENCE REVIEWS LA English DT Review ID EARTHS BOW SHOCK; COMET GIACOBINI-ZINNER; HYDROMAGNETIC WAVE EXCITATION; LOW-FREQUENCY WAVES; SHEET BOUNDARY-LAYER; AMPLITUDE MHD WAVES; INTERPLANETARY TRAVELING SHOCKS; MAGNETIC-FIELD OBSERVATIONS; QUASI-LINEAR THEORY; SOLAR-WIND STREAMS AB This paper reviews recent research on the theory and computer simulations of electromagnetic ion/ion instabilities and their consequences in space plasmas. 'Ion/ion' instabilities are growing modes in a collisionless plasma driven unstable by the relative streaming velocity v(o) of two distinct ion components such that v(o) is parallel or antiparallel to the uniform background magnetic field B(o). The space physics regimes which display enhanced fluctuations due to these instabilities and which are reviewed in this paper include the solar wind, the terrestrial foreshock, the plasma sheet boundary layer, and distant cometary environments. RP GARY, SP (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 162 TC 173 Z9 176 U1 1 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD MAY PY 1991 VL 56 IS 3-4 BP 373 EP 415 PG 43 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FD497 UT WOS:A1991FD49700003 ER PT J AU ANDERSON, DV COOPER, WA GRUBER, R MERAZZI, S SCHWENN, U AF ANDERSON, DV COOPER, WA GRUBER, R MERAZZI, S SCHWENN, U TI THE TERPSICHORE CODE FOR THE STABILITY ANALYSIS OF MAGNETICALLY CONFINED FUSION PLASMAS SO SUPERCOMPUTER LA English DT Article ID BETA AB We describe a few relevant aspects of the new plasma physics stability code, TERPSICHORE, which breaks new ground both in plasma theory and in its algorithmic implementation. We chose a highly accurate discrete mathematical representation which led to the choice of algorithms that matched the vector-parallel architecture of the Cray Y-MP and Cray-2 supercomputers quite well. The resulting code runs at Gflop/s speeds, which translates into a very high efficiency. This means we can perform very extensive studies within our limited computer budgets. C1 ECOLE POLYTECH FED LAUSANNE,CH-1015 LAUSANNE,SWITZERLAND. MAX PLANCK INST PLASMA PHYS,W-8046 GARCHING,GERMANY. RP ANDERSON, DV (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,POB 509 L-561,LIVERMORE,CA 94550, USA. NR 11 TC 2 Z9 2 U1 1 U2 1 PU ASFRA PI EDAM PA VOORHAVEN 33, 1135 BL EDAM, NETHERLANDS SN 0168-7875 J9 SUPERCOMPUTER JI Supercomputer PD MAY PY 1991 VL 8 IS 3 BP 32 EP 35 PG 4 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA FY020 UT WOS:A1991FY02000005 ER PT J AU ALARIE, JP VO-DINH, T AF ALARIE, JP VO-DINH, T TI A FIBEROPTIC CYCLODEXTRIN-BASED SENSOR SO TALANTA LA English DT Article ID ROOM-TEMPERATURE PHOSPHORESCENCE; BETA-CYCLODEXTRIN AB This paper describes the development of a fiber-optic cyclodextrin-based (FCD) sensor. The device uses laser excitation and fluorescence detection with beta-cyclodextrin as the reagent phase, immobilized at the tip of an optical fiber. The sensitivity of the FCD sensor is 14 times as great as that of a bare optical fiber when measurements are made with the fiber immersed in a buffer after a 10-min incubation period. The selectivity of the sensor is illustrated with pyrene as the model compound and 5,6-benzoquinoline as the interferent. An interference study with a contaminated environmental ground water sample is used to illustrate the usefulness of the FCD device. C1 OAK RIDGE NATL LAB, DIV HLTH & SAFETY RES, ADV MONITORING DEV GRP, OAK RIDGE, TN 37831 USA. NR 17 TC 32 Z9 32 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-9140 J9 TALANTA JI Talanta PD MAY PY 1991 VL 38 IS 5 BP 529 EP 534 DI 10.1016/0039-9140(91)80176-Z PG 6 WC Chemistry, Analytical SC Chemistry GA FN630 UT WOS:A1991FN63000013 PM 18965183 ER PT J AU DIMMEL, DR BOZELL, JJ AF DIMMEL, DR BOZELL, JJ TI PULPING CATALYSTS FROM LIGNIN SO TAPPI JOURNAL LA English DT Note DE ADDITIVES; ANTHRAQUINONE; LIGNINS; PULPING AB There are benefits to anthraquinone-catalyzed pulping, but the current cost of anthraquinone (AQ) discourages its general use. A process is under development to obtain low-cost AQ catalysts from lignin. This process converts low-molecular-weight lignins to mixtures of methyoxy-substituted benzoquinones and reacts the benzoquinones with dienes to provide mixtures rich in AQ and AQ analogs. The authors describe the processes by which low-molecular-weight lignins are selectively isolated, lignins are transformed to benzoquinones, and benzoquinones are converted to anthraquinones. Research is directed toward developing optimum efficiency in lignin extraction and chemical conversion in order to lower the cost of obtaining pulping catalysts from lignin. A cost-effective soda-anthraquinone process will greatly reduce the air emissions associated with current processes and simplify chemical recovery and environmental processing. If catalyst costs can be kept low, an anthraquinone process can be an opportunity to improve productivity, conserve raw materials, and save energy. C1 SOLAR ENERGY RES INST,GOLDEN,CO 80401. RP DIMMEL, DR (reprint author), INST PAPER SCI & TECHNOL,575 14TH ST NW,ATLANTA,GA 30318, USA. NR 8 TC 12 Z9 12 U1 0 U2 3 PU TECH ASSN PULP PAPER IND INC PI NORCROSS PA 15 TECHNOLOGY PARK SOUTH, NORCROSS, GA 30092 SN 0734-1415 J9 TAPPI J JI TAPPI J. PD MAY PY 1991 VL 74 IS 5 BP 239 EP 241 PG 3 WC Materials Science, Paper & Wood SC Materials Science GA FK054 UT WOS:A1991FK05400027 ER PT J AU MORRIS, MD AF MORRIS, MD TI FACTORIAL SAMPLING PLANS FOR PRELIMINARY COMPUTATIONAL EXPERIMENTS SO TECHNOMETRICS LA English DT Article DE COMPUTATIONAL MODEL; FACTOR SCREENING; LATIN HYPERCUBE SAMPLING; SENSITIVITY ANALYSIS ID SENSITIVITY; DESIGNS; MODELS AB A computational model is a representation of some physical or other system of interest, first expressed mathematically and then implemented in the form of a computer program; it may be viewed as a function of inputs that, when evaluated, produces outputs. Motivation for this article comes from computational models that are deterministic, complicated enough to make classical mathematical analysis impractical and that have a moderate-to-large number of inputs. The problem of designing computational experiments to determine which inputs have important effects on an output is considered. The proposed experimental plans are composed of individually randomized one-factor-at-a-time designs, and data analysis is based on the resulting random sample of observed elementary effects, those changes in an output due solely to changes in a particular input. Advantages of this approach include a lack of reliance on assumptions of relative sparsity of important inputs, monotonicity of outputs with respect to inputs, or adequacy of a low-order polynomial as an approximation to the computational model. RP MORRIS, MD (reprint author), OAK RIDGE NATL LAB,DIV ENGN PHYS & MATH,OAK RIDGE,TN 37831, USA. NR 15 TC 983 Z9 1053 U1 20 U2 124 PU AMER STATIST ASSN PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD MAY PY 1991 VL 33 IS 2 BP 161 EP 174 DI 10.2307/1269043 PG 14 WC Statistics & Probability SC Mathematics GA FJ198 UT WOS:A1991FJ19800006 ER PT J AU SCHMOYER, RL AF SCHMOYER, RL TI NONPARAMETRIC ANALYSES FOR 2-LEVEL SINGLE-STRESS ACCELERATED LIFE TESTS SO TECHNOMETRICS LA English DT Article DE ACCELERATED FAILURE TIME; CENSORED DATA; PROPORTIONAL HAZARDS ID PROPORTIONAL HAZARDS; REGRESSION-MODELS; GOODNESS; FIT AB In accelerated life testing, information is sought about a process at normal stress levels by studying it at higher stress levels. Let Pr(t; x) be the probability of failure by time t of an item subjected to level x of a stress. In this article, I consider the nonparametric proportional hazards model. Pr(t; x) = 1 - e(-g)(x)h(t), and the nonparametric accelerated failure time model, Pr(t; x) = F(g(x)t), where g and h are nonnegative nondecreasing functions of x and t, respectively; F is an arbitrary distribution function; and g has sigmoid (S-shaped) curvature. I develop confidence bounds for low-stress long-time probabilities and quantiles. I also discuss a goodness-of-fit test of the proportional hazards model. The results, which are primarily for data at two levels of stress, accommodate simple right censoring. RP SCHMOYER, RL (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 22 TC 9 Z9 10 U1 0 U2 2 PU AMER STATIST ASSN PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD MAY PY 1991 VL 33 IS 2 BP 175 EP 186 DI 10.2307/1269044 PG 12 WC Statistics & Probability SC Mathematics GA FJ198 UT WOS:A1991FJ19800007 ER PT J AU HATTEMERFREY, HA TRAVIS, CC AF HATTEMERFREY, HA TRAVIS, CC TI BENZO-A-PYRENE - ENVIRONMENTAL PARTITIONING AND HUMAN EXPOSURE SO TOXICOLOGY AND INDUSTRIAL HEALTH LA English DT Article DE BENZO-A-PYRENE; FOOD CHAIN; RISK; HUMAN EXPOSURE; ENVIRONMENTAL PARTITIONING ID POLYCYCLIC AROMATIC-HYDROCARBONS; PLANT FOLIAGE; POLYCHLORINATED-BIPHENYLS; BENZO(A)PYRENE; CHEMICALS; MODEL; BIOCONCENTRATION; TRANSLOCATION; TRANSPORT; FUGACITY AB A multimedia transport model was used to evaluate the environmental partitioning of benzo-a-pyrene (BaP). Measured and predicted environmental concentrations were used to estimate the accumulation of BaP in the food chain and the subsequent extent of human exposure from inhalation and ingestion. Results show that BaP partitions mainly into soil (82%) and sediment (17%) and that the food chain is the dominant pathway of human exposure, accounting for about 97% of the total daily intake of BaP. Inhalation and consumption of contaminated water are only minor pathways of human exposure. The long-term average daily intake of BaP by the general population of the U.S. is estimated to be 2.2 micrograms (mu-g) per day. Cigarette smoking and indoor activities do not substantially increase human exposure to BaP relative to exposures to background levels of BaP present in the environment. Since the increased lifetime risk associated with human exposure to background levels of BaP is 3.5 X 10(-4), we conclude that ingestion of food items contaminated with BaP may pose a serious health threat to the U.S. population. C1 OAK RIDGE NATL LAB,DIV HLTH & SAFETY RES,OFF RISK ANAL,OAK RIDGE,TN 37831. RP HATTEMERFREY, HA (reprint author), LEE WAN & ASSOCIATES INC,120 S JEFFERSON CIRCLE,SUITE 100,OAK RIDGE,TN 37830, USA. NR 70 TC 152 Z9 157 U1 2 U2 14 PU PRINCETON SCIENTIFIC PUBL INC PI PRINCETON PA PO BOX 2155, PRINCETON, NJ 08543 SN 0748-2337 J9 TOXICOL IND HEALTH JI Toxicol. Ind. Health PD MAY PY 1991 VL 7 IS 3 BP 141 EP 157 PG 17 WC Public, Environmental & Occupational Health; Toxicology SC Public, Environmental & Occupational Health; Toxicology GA GC665 UT WOS:A1991GC66500003 PM 1949056 ER PT J AU BOIS, FY SMITH, MT SPEAR, RC AF BOIS, FY SMITH, MT SPEAR, RC TI MECHANISMS OF BENZENE CARCINOGENESIS - APPLICATION OF A PHYSIOLOGICAL MODEL OF BENZENE PHARMACOKINETICS AND METABOLISM SO TOXICOLOGY LETTERS LA English DT Article DE BENZENE; CARCINOGENIC EFFECTS; METABOLISM; PHARMACOKINETICS; PHENOL; PHYSIOLOGICAL MODEL ID INHALED BENZENE; B6C3F1 MICE; PHENOL; RATS; DISPOSITION; EXPOSURE; CATECHOL; INVIVO; HYDROQUINONE; INHALATION AB A physiological pharmacokinetic model for benzene, incorporating metabolic transformations, is used to explore why benzene, but not phenol - its primary metabolite - is carcinogenic at many sites in rats. The model has been parametrized using in vitro or in vivo experimental data. Ranges, rather than fixed values, were assigned to the parameters. The model-predicted levels of phenol and hydroquinone in the tissues are consistently higher when phenol, rather than benzene, is administrated. This result demonstrates that the differential carcinogenicity of the two compounds is not explainable in the context of this pharmacokinetic analysis. It also indicates that the phenol-hydroquinone pathway alone is unlikely to account for the carcinogenic effects of benzene. Other metabolites must therefore also be involved. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP BOIS, FY (reprint author), UNIV CALIF BERKELEY,SCH PUBL HLTH,BERKELEY,CA 94720, USA. RI Bois, Frederic/E-9241-2012 OI Bois, Frederic/0000-0002-4154-0391 FU NIEHS NIH HHS [P42 ES04705] NR 33 TC 33 Z9 33 U1 0 U2 2 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0378-4274 J9 TOXICOL LETT JI Toxicol. Lett. PD MAY PY 1991 VL 56 IS 3 BP 283 EP 298 DI 10.1016/0378-4274(91)90157-2 PG 16 WC Toxicology SC Toxicology GA FN017 UT WOS:A1991FN01700005 PM 2035176 ER PT J AU MEFFE, GK AF MEFFE, GK TI FAILED INVASION OF A SOUTHEASTERN BLACKWATER STREAM BY BLUEGILLS - IMPLICATIONS FOR CONSERVATION OF NATIVE COMMUNITIES SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID FISH ASSEMBLAGE; PERSISTENCE; STABILITY AB I studied three sites in an undisturbed, third-order blackwater stream in the central Savannah River drainage of South Carolina for 2 years before and 3 years after the accidental introduction of bluegills Lepomis macrochirus. Although large numbers invaded the stream, the species declined over the next 3 years and will likely disappear soon. The bluegills had no measurable effect on the numbers of species or individuals of the stream's indigenous fish fauna. Nearby in the same drainage, bluegills successfully colonized an impounded cooling reservoir and a downstream swamp, but they did not become established in the high-flow stream below the reservoir. Unsuccessful colonization of the two flowing-water systems indicates the importance of impoundments to successful colonization by many nonnative fishes. These data, together with examples from arid-zone streams of the American Southwest, illustrate that unimpeded flow in lotic habitats may protect against successful invasion by some introduced fishes, whereas stabilized flows may increase their likelihood of establishment. RP MEFFE, GK (reprint author), UNIV GEORGIA,SAVANNAH RIVER ECOL LAB,DRAWER E,AIKEN,SC 29802, USA. NR 20 TC 19 Z9 20 U1 0 U2 4 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAY PY 1991 VL 120 IS 3 BP 333 EP 338 DI 10.1577/1548-8659(1991)120<0333:FIOASB>2.3.CO;2 PG 6 WC Fisheries SC Fisheries GA FZ418 UT WOS:A1991FZ41800006 ER PT J AU TRASK, BJ AF TRASK, BJ TI FLUORESCENCE INSITU HYBRIDIZATION - APPLICATIONS IN CYTOGENETICS AND GENE-MAPPING SO TRENDS IN GENETICS LA English DT Article ID INTERPHASE CELL-NUCLEI; CHROMOSOME-ABERRATIONS; DNA-SEQUENCES; PROBES; ORGANIZATION; LOCALIZATION; SENSITIVITY; METAPHASE; HYBRIDS AB Unique sequences, chromosomal subregions, or entire genomes can be specifically highlighted in metaphase or interphase cells by fluorescence in situ hybridization (FISH). This technique can be used to identify chromosomes, detect chromosomal abnormalities or determine the chromosomal location of specific sequences. FISH plays an increasingly important role in a variety of research areas, including cytogenetics, prenatal diagnosis, tumor biology, gene amplification and gene mapping. RP TRASK, BJ (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,LIVERMORE,CA 94550, USA. NR 41 TC 345 Z9 350 U1 0 U2 16 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0168-9525 J9 TRENDS GENET JI Trends Genet. PD MAY PY 1991 VL 7 IS 5 BP 149 EP 154 DI 10.1016/0168-9525(91)90103-W PG 6 WC Genetics & Heredity SC Genetics & Heredity GA FJ476 UT WOS:A1991FJ47600005 PM 2068787 ER PT J AU KING, PL BORG, A KIM, C YOSHIKAWA, SA PIANETTA, P LINDAU, I AF KING, PL BORG, A KIM, C YOSHIKAWA, SA PIANETTA, P LINDAU, I TI SYNCHROTRON-BASED IMAGING WITH A MAGNETIC PROJECTION PHOTOELECTRON MICROSCOPE SO ULTRAMICROSCOPY LA English DT Article ID PHOTOEMISSION ELECTRON-MICROSCOPY; X-RAY; SPECTROMICROSCOPY; RESOLUTION; RADIATION; SURFACE; UV AB The magnetic projection photoelectron microscope performs imaging photoelectron and photoabsorption spectroscopy with a lateral resolution of the order of microns. We review practical experience accumulated in two months of synchrotron-based operations. Theoretical limitations and practical issues related to count rates, elemental and chemical contrast and extraneous noise are discussed. A comparison is made between our experience with retarding field analysis and a conceptual imaging band-pass analyzer. Recent observations from surface diffusion experiments are presented. C1 UNIV TRONDHEIM, N-7034 TRONDHEIM, NORWAY. RP STANFORD SYNCHROTRON RADIAT LAB, STANFORD, CA 94309 USA. NR 23 TC 10 Z9 10 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 EI 1879-2723 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD MAY PY 1991 VL 36 IS 1-3 BP 117 EP 129 DI 10.1016/0304-3991(91)90143-T PG 13 WC Microscopy SC Microscopy GA FR138 UT WOS:A1991FR13800009 ER PT J AU GOODS, SH KARFS, CW AF GOODS, SH KARFS, CW TI HELIUM-INDUCED WELD CRACKING IN LOW HEAT INPUT GMA WELD OVERLAYS SO WELDING JOURNAL LA English DT Article DE HE-INDUCED CRACKING; GMAW; GMAW OVERLAYS; AUSTENITIC STAINLESS; FUSION-ZONE POROSITY; HAZ CRACKING; WELD HEAT INPUT; WELDABILITY; MICROSTRUCTURE; INTERGRANULAR CRACKS ID INTERGRANULAR CAVITY GROWTH; FRACTURE; CREEP AB The influence of entrapped helium on weldability was examined for an AISI Type 304 stainless steel. Two types of welding processes were compared: conventional, deep penetration, gas metal arc stringer bead welding, and a novel, very shallow penetration gas metal arc weld overlay process. Helium concentrations ranging between 2.7 and 85.0 atomic parts per million were generated in test specimens by tritium charging them to saturation and then allowing the dissolved tritium to decay to He-3. Detailed scanning electron microscopy subsequent to welding revealed the presence of cracking in the heat-affected zone of all samples, including the lowest heat input weld overlays. No such cracking was observed in helium-free control specimens. In every instance, the cracking in the helium-bearing specimens was intergranular. The grain boundary facets of these intergranular cracks were decorated with a uniform distribution of dimples similar to that typically associated with high-temperature gas bubble embrittlement. While all of the helium-bearing specimens exhibited some amount of cracking (as measured by crack length, location and total number of cracks), the extent of cracking was significantly reduced in the shallow penetration overlays vs. the stringer bead welds. RP GOODS, SH (reprint author), SANDIA NATL LABS,DIV ENGN MAT,LIVERMORE,CA 94550, USA. NR 18 TC 1 Z9 1 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA PO BOX 351040, MIAMI, FL 33135 SN 0043-2296 J9 WELD J JI Weld. J. PD MAY PY 1991 VL 70 IS 5 BP S123 EP S132 PG 10 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA FJ483 UT WOS:A1991FJ48300015 ER PT J AU SANO, T CANTOR, CR AF SANO, T CANTOR, CR TI EXPRESSION VECTORS FOR STREPTAVIDIN-CONTAINING CHIMERIC PROTEINS SO BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS LA English DT Article ID PHOSPHOROTHIOATE-MODIFIED DNA; T7 RNA-POLYMERASE; CLEAVAGE C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CTR HUMAN GENOME,BERKELEY,CA 94720. RP SANO, T (reprint author), UNIV CALIF BERKELEY,DEPT MOLEC & CELL BIOL,BERKELEY,CA 94720, USA. FU NCI NIH HHS [CA39782] NR 25 TC 38 Z9 40 U1 0 U2 2 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0006-291X J9 BIOCHEM BIOPH RES CO JI Biochem. Biophys. Res. Commun. PD APR 30 PY 1991 VL 176 IS 2 BP 571 EP 577 DI 10.1016/S0006-291X(05)80222-0 PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA FK023 UT WOS:A1991FK02300004 PM 2025272 ER PT J AU MEIER, ML LESUER, DR MUKHERJEE, AK AF MEIER, ML LESUER, DR MUKHERJEE, AK TI ALPHA-GRAIN SIZE AND BETA-VOLUME FRACTION ASPECTS OF THE SUPERPLASTICITY OF TI-6AL-4V SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article AB The elevated temperature deformation behaviour of Ti-6Al-4V has been investigated in the temperature range between 775 and 925-degrees-C and for true strain rates 2 x 10(-5) to 0.05 s-1. Region III was characterized by m = 0.13 and Q = 602 kJ mol-1. Region II is subdivided into a low temperature region IIa and a high temperature region IIb. Region IIa is characterized by m = 0.77, Q = 216 kJ mol-1 and relatively low ductility while region IIb is characterized by n = 1.3, an identical value of Q and high ductility. Low and high beta-phase proportions are responsible for regions IIa and IIb respectively. An apparent region I was accounted for by concurrent grain growth utilizing a grain size sensitivity parameter which is dependent on the beta-phase volume fraction. The strain rate-temperature regimes of regions IIa, IIb and III are illustrated in a "region" map. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DIV ENGN SCI,LIVERMORE,CA 94550. RP MEIER, ML (reprint author), UNIV CALIF DAVIS,DEPT MECH AERONAUT & MAT ENGN,DAVIS,CA 95616, USA. NR 19 TC 38 Z9 39 U1 2 U2 10 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD APR 30 PY 1991 VL 136 BP 71 EP 78 DI 10.1016/0921-5093(91)90442-P PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA FM670 UT WOS:A1991FM67000008 ER PT J AU YUAN, RK CHENG, GX ZHENG, YD SHEN, XC TANG, WG GINLEY, DS AF YUAN, RK CHENG, GX ZHENG, YD SHEN, XC TANG, WG GINLEY, DS TI STUDY OF THE BEHAVIOR OF DOPED IMPURITY IN P3MT BY RAMAN, PL AND PR SPECTROSCOPIES SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF OF SCIENCE AND TECHNOLOGY OF SYNTHETIC METALS ( ICSM 90 ) CY SEP 02-07, 1990 CL TUBINGEN, FED REP GER SP DEUT FORSCHUNGSGEMEINSCH, LAND BADEN WURTTEMBERG, UNIV TUBINGEN, BASF, BAYER, HOECHST, HEWLETT PACKARD, SIEMENS, WACKER CHEM, ZIPPERLING KESSLER & CO ID POLYACETYLENE; POLARONS; MODEL AB The behaviour of doped impurity in poly (3-methyl thiophene) - P3MT has been studied by Raman, photoluminescence (PL) and photoreflectance (PR) spectroscopies. It is experimentally demonstrated that the behaviour of doped impurity in conducting polymer P3MT is different from that in conventional inorganic semiconductors. The doped impurity is located at the spaces between the molecular chains in P3MT film and the band gap of P3MT increases with doping density. C1 SHANGHAI INST TECH PHYS,SHANGHAI,PEOPLES R CHINA. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP YUAN, RK (reprint author), NANKAI UNIV,DEPT PHYS,TIANJIN,PEOPLES R CHINA. NR 8 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD APR 30 PY 1991 VL 41 IS 1-2 BP 543 EP 546 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA FU747 UT WOS:A1991FU74700146 ER PT J AU SHINAR, J SWANSON, LS YOSHINO, K AF SHINAR, J SWANSON, LS YOSHINO, K TI TRIPLET POLARONIC EXCITONS IN POLY(3-ALKYLTHIOPHENE) FILMS AND SOLUTIONS - INTERCHAIN OR INTRACHAIN SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF OF SCIENCE AND TECHNOLOGY OF SYNTHETIC METALS ( ICSM 90 ) CY SEP 02-07, 1990 CL TUBINGEN, FED REP GER SP DEUT FORSCHUNGSGEMEINSCH, LAND BADEN WURTTEMBERG, UNIV TUBINGEN, BASF, BAYER, HOECHST, HEWLETT PACKARD, SIEMENS, WACKER CHEM, ZIPPERLING KESSLER & CO ID STRETCHED POLYTHIOPHENE FILMS; MAGNETIC-RESONANCE; POLY(3-HEXYLTHIOPHENE); ANISOTROPIES; POLYMERS; SPECTRA; SOLIDS AB The X-band optically detected magnetic resonance of poly(3-hexylthiophene) and poly(3-dodecylthiophene) films was measured at 9.35GHz from 5 - 300K, and in dilute solution at 300K. The main narrow resonance, assigned to "distant" intrachain polaron recombination, is temperature independent and identical in films and solutions. A broad pattern about g approximately 2, assigned to triplet polaronic exciton decay, is observable in films up to 300K, but not in solutions. The nature of these excitons is discussed. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. OSAKA UNIV,FAC ENGN,DEPT ELECT ENGN,SUITA,OSAKA 565,JAPAN. RP SHINAR, J (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD APR 30 PY 1991 VL 41 IS 1-2 BP 555 EP 558 DI 10.1016/0379-6779(91)91131-S PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA FU747 UT WOS:A1991FU74700149 ER PT J AU KRISHNAN, KM AF KRISHNAN, KM TI STRUCTURE OF NEWLY SYNTHESIZED BC3 FILMS SO APPLIED PHYSICS LETTERS LA English DT Article ID GRAPHITE AB We have measured the electron energy-loss spectrum (EELS) of BC3 at sub-eV resolution. Important differences between the total density of states of BC3 at the threshold of the K edge, predicted by earlier ab initio calculations, have been observed. We conclude from our measurements that the atomic arrangement in these materials can be described as graphite sheets with B replacing every third C atom. We suggest that further understanding of the electronic structure of BC3 can be derived by comparing such EELS data with calculations of the local density of states of bulk BC3 and including interlayer interaction. RP KRISHNAN, KM (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,NATL CTR ELECTRON MICROSCOPY,DIV MAT SCI,1 CYCLOTRON RD,LOS ALAMOS,NM 87545, USA. NR 5 TC 41 Z9 42 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 29 PY 1991 VL 58 IS 17 BP 1857 EP 1859 DI 10.1063/1.105053 PG 3 WC Physics, Applied SC Physics GA FJ597 UT WOS:A1991FJ59700018 ER PT J AU EVANS, PM SMITH, AE PASS, CN STUTTGE, L BACK, BB BETTS, RR DICHTER, BK HENDERSON, DJ SANDERS, SJ VIDEBAEK, F WILKINS, BD AF EVANS, PM SMITH, AE PASS, CN STUTTGE, L BACK, BB BETTS, RR DICHTER, BK HENDERSON, DJ SANDERS, SJ VIDEBAEK, F WILKINS, BD TI DISSIPATIVE REACTION-MECHANISMS IN MEDIUM-MASS NUCLEAR COLLISIONS SO NUCLEAR PHYSICS A LA English DT Article ID FISSION-LIKE FRAGMENTATION; SURFACE-BARRIER DETECTORS; FUSION REACTIONS; ASYMMETRY; SYSTEM; DISTRIBUTIONS; S-32+CO-59; DYNAMICS; ENERGY; NI-56 AB Mass, energy, charge and angular distributions from fully damped reactions of the Ca-40 + Ca-40 systems have been measured at 197 and 231 MeV, in both singles and coincidence. The data display features of compound nucleus fission. Comparison with similar, but asymmetric systems, however, shows an entrance-channel dependence which invalidates a fusion-fission description. A discussion in terms of fission barriers calculated using the finite-range liquid drop model suggests a fast-fission mechanism. Re-analyses of systems studied in the literature are presented in terms of the finite-range liquid drop model, indicating fast fission-a process previously assumed only to be relevant for heavier systems-to be significant in most cases. Furthermore, using the finite-range liquid drop model, we find that the systematic behaviour of the mass distributions from systems where complete fusion-fission is expected to be dominant is well described in terms of the revised locus of the Businaro-Gallone transition from symmetric to asymmetric fission. C1 UNIV OXFORD,DEPT NUCL PHYS,OXFORD OX1 3RH,ENGLAND. ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. RI Evans, Philip/A-6257-2009 NR 49 TC 13 Z9 13 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD APR 29 PY 1991 VL 526 IS 2 BP 365 EP 394 DI 10.1016/0375-9474(91)90291-D PG 30 WC Physics, Nuclear SC Physics GA FJ831 UT WOS:A1991FJ83100007 ER PT J AU ATIYA, MS CHIANG, IH FRANK, JS HAGGERTY, JS ITO, MM KYCIA, TF LI, KK LITTENBERG, LS STEVENS, A STRAND, RC LOUIS, WC AKERIB, DS MARLOW, DR MEYERS, PD SELEN, MA SHOEMAKER, FC SMITH, AJS AZUELOS, G BLACKMORE, EW BRYMAN, DA FELAWKA, L KITCHING, P KUNO, Y MACDONALD, JA NUMAO, T PADLEY, P POUTISSOU, JM POUTISSOU, R ROY, J AF ATIYA, MS CHIANG, IH FRANK, JS HAGGERTY, JS ITO, MM KYCIA, TF LI, KK LITTENBERG, LS STEVENS, A STRAND, RC LOUIS, WC AKERIB, DS MARLOW, DR MEYERS, PD SELEN, MA SHOEMAKER, FC SMITH, AJS AZUELOS, G BLACKMORE, EW BRYMAN, DA FELAWKA, L KITCHING, P KUNO, Y MACDONALD, JA NUMAO, T PADLEY, P POUTISSOU, JM POUTISSOU, R ROY, J TI UPPER LIMIT ON THE BRANCHING RATIO FOR THE DECAY PI-0-]VVBAR SO PHYSICAL REVIEW LETTERS LA English DT Article AB An experimental upper limit on the branching ratio for the decay pi-0 --> nu-nu-BAR is set at 8.3 x 10(-7) (90% C.L.). This decay is forbidden if neutrinos are purely left handed. The limit also applies to any decays of the pi-0 to weakly interacting neutrals. C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV MEDIUM ENERGY PHYS,LOS ALAMOS,NM 87545. TRIUMF,VANCOUVER V6T 2A3,BC,CANADA. PRINCETON UNIV,JOSEPH HENRY LABS,PRINCETON,NJ 08544. RP ATIYA, MS (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. RI Marlow, Daniel/C-9132-2014 NR 12 TC 22 Z9 22 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 APR 29 PY 1991 VL 66 IS 17 BP 2189 EP 2192 DI 10.1103/PhysRevLett.66.2189 PG 4 WC Physics, Multidisciplinary SC Physics GA FJ598 UT WOS:A1991FJ59800004 ER PT J AU GORGEN, JJ COMFORT, JR TINSLEY, JR AVERETT, T DEKORSE, J FRANKLIN, B RITCHIE, BG KYLE, G KLEIN, A BERMAN, B BURLESON, G CRANSTON, K FAUCETT, JA JARMER, JJ KNUDSON, JN PENTTILA, S TANAKA, N BRINKMOLLER, B DEHNHARD, D YEN, YF HOIBRATEN, S BREUER, H FLANDERS, BS KHANDAKER, MA NAPLES, DL ZHANG, D BARLETT, ML HOFFMANN, GW PURCELL, M AF GORGEN, JJ COMFORT, JR TINSLEY, JR AVERETT, T DEKORSE, J FRANKLIN, B RITCHIE, BG KYLE, G KLEIN, A BERMAN, B BURLESON, G CRANSTON, K FAUCETT, JA JARMER, JJ KNUDSON, JN PENTTILA, S TANAKA, N BRINKMOLLER, B DEHNHARD, D YEN, YF HOIBRATEN, S BREUER, H FLANDERS, BS KHANDAKER, MA NAPLES, DL ZHANG, D BARLETT, ML HOFFMANN, GW PURCELL, M TI ANALYZING POWERS FOR PION CHARGE-EXCHANGE ON POLARIZED C-13 SO PHYSICAL REVIEW LETTERS LA English DT Article ID SCATTERING; NUCLEI AB Results of the first pion single-charge-exchange experiment on a polarized nuclear target are reported. Analyzing powers A(y) for the (pi+, pi-0) reaction at T-pi+ = 163 MeV on a polarized C-13 target were measured over an angular range between 20-degrees and 60-degrees in the laboratory system. Calculations in the distorted-wave impulse approximation do not reproduce these new data. C1 NEW MEXICO STATE UNIV,DEPT PHYS,LAS CRUCES,NM 88003. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. UNIV MINNESOTA,DEPT PHYS,MINNEAPOLIS,MN 55455. UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309. UNIV TEXAS,DEPT PHYS,AUSTIN,TX 78712. RP GORGEN, JJ (reprint author), ARIZONA STATE UNIV,DEPT PHYS,TEMPE,AZ 85287, USA. RI Averett, Todd/A-2969-2011 NR 20 TC 17 Z9 17 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 29 PY 1991 VL 66 IS 17 BP 2193 EP 2196 DI 10.1103/PhysRevLett.66.2193 PG 4 WC Physics, Multidisciplinary SC Physics GA FJ598 UT WOS:A1991FJ59800005 ER PT J AU LHUILLIER, A SCHAFER, KJ KULANDER, KC AF LHUILLIER, A SCHAFER, KJ KULANDER, KC TI HIGH-ORDER HARMONIC-GENERATION IN XENON AT 1064-NM - THE ROLE OF PHASE MATCHING SO PHYSICAL REVIEW LETTERS LA English DT Article ID MULTIPHOTON IONIZATION; RARE-GASES; RADIATION; CONVERSION AB We present a completely ab initio calculation of harmonic generation in xenon exposed to a strong laser field. The time-dependent Schrodinger equation for the atomic response and the propagation equation are numerically integrated yielding excellent agreement with experiment. The weaker variation with pump intensity of the induced dipole in the high-field regime leads to an enormous enhancement in phase matching compared to the perturbative limit and a defocusing of the generated harmonics. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP LHUILLIER, A (reprint author), CENS,SERV PHYS ATOMES & SURFACES,F-91191 GIF SUR YVETTE,FRANCE. RI L'Huillier, Anne/P-4379-2015 OI L'Huillier, Anne/0000-0002-1335-4022 NR 21 TC 114 Z9 114 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 APR 29 PY 1991 VL 66 IS 17 BP 2200 EP 2203 DI 10.1103/PhysRevLett.66.2200 PG 4 WC Physics, Multidisciplinary SC Physics GA FJ598 UT WOS:A1991FJ59800007 ER PT J AU GONIS, A SOWA, EC STERNE, PA AF GONIS, A SOWA, EC STERNE, PA TI EXACT TREATMENT OF POISSON EQUATION IN SOLIDS WITH SPACE-FILLING CELLS SO PHYSICAL REVIEW LETTERS LA English DT Article AB We present a new, rigorous treatment of Poisson's equation in solids with no shape approximation to the potential. In contrast to existing techniques, this method allows the unified treatment of periodic solids, as well as materials containing imperfections such as substitutional or interstitial impurities and disordered alloys. Explicit expressions for the potential and the Coulomb part of the energy are given. The validity and utility of this approach is demonstrated by numerical calculations. RP GONIS, A (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,LIVERMORE,CA 94550, USA. NR 10 TC 23 Z9 23 U1 1 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 APR 29 PY 1991 VL 66 IS 17 BP 2207 EP 2210 DI 10.1103/PhysRevLett.66.2207 PG 4 WC Physics, Multidisciplinary SC Physics GA FJ598 UT WOS:A1991FJ59800009 ER PT J AU ZUO, JK WENDELKEN, JF AF ZUO, JK WENDELKEN, JF TI SCALING OF THE (SQUARE-ROOT-3XSQUARE-ROOT-3) R30-DEGREES DOMAIN-SIZE DISTRIBUTION WITH COVERAGE FOR AG/SI(111) SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHEMISORBED OVERLAYER; SURFACE; DIFFRACTION; AGGREGATION; CLUSTERS; GROWTH AB The evolution of the (square-root 3 X square-root 3)R30-degrees domain-size distribution with coverage for Ag on Si(111) has been studied by high-resolution low-energy electron diffraction. Scaling of the size distribution, which can be fitted by a gamma distribution, is observed. A temperature dependence of the exponent n describing a power growth law for mean size versus coverage is found where n decreases with decreasing deposition temperature. By introducing a simple relation, q + nd = 1, where the dimensionality d = 2 and q is an exponent describing the power law for domain density versus coverage, the behavior of n is explained in terms of the experimentally observed behavior of q. RP ZUO, JK (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. NR 19 TC 54 Z9 56 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 APR 29 PY 1991 VL 66 IS 17 BP 2227 EP 2230 DI 10.1103/PhysRevLett.66.2227 PG 4 WC Physics, Multidisciplinary SC Physics GA FJ598 UT WOS:A1991FJ59800014 ER PT J AU LIU, CJ DUNFORD, RW AF LIU, CJ DUNFORD, RW TI DEPOLARIZATION FOLLOWING ELECTRON-CAPTURE BY HIGHLY CHARGED IONS IN A POLARIZED TARGET SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID NUCLEAR-POLARIZATION; COLLISIONS; ORIENTATION; EXCITATION; ALIGNMENT; EXCHANGE; HYDROGEN; PROTON; LIGHT; PROJECTILES AB We analyse the electron-spin depolarization of highly charged hydrogenic and alkali-like ions formed by single-electron capture in an electron-spin-polarized target. In general, ions are formed in highly excited states and are depolarized by the fine- and hyperfine-structure interaction as they cascade down to the ground state. The final polarization is determined by the state into which the electron is captured, the alignment of the excited state formed in the capture process, the nuclear spin, and the angle between the target electron-spin polarization vector and the ion-beam axis. We also calculate the polarization of the radiation emitted following polarized-electron capture. We point out that the circular and linear polarization of the emission line can be monitored to determine the polarization of the ions. RP LIU, CJ (reprint author), ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439, USA. NR 43 TC 2 Z9 2 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD APR 28 PY 1991 VL 24 IS 8 BP 2059 EP 2071 DI 10.1088/0953-4075/24/8/020 PG 13 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FK731 UT WOS:A1991FK73100020 ER PT J AU MCCOY, JD HONNELL, KG SCHWEIZER, KS CURRO, JG AF MCCOY, JD HONNELL, KG SCHWEIZER, KS CURRO, JG TI POLYMER CRYSTALLIZATION - DENSITY FUNCTIONAL THEORY AND APPLICATION TO POLYETHYLENE SO CHEMICAL PHYSICS LETTERS LA English DT Article ID NONUNIFORM POLYATOMIC SYSTEMS; SIMPLE LIQUIDS; BUTANE; MELTS AB A general microscopic approach for the crystallization of flexible polymer melts is formulated and applied to polyethylene. RP MCCOY, JD (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. RI McCoy, John/B-3846-2010 OI McCoy, John/0000-0001-5404-1404 NR 29 TC 17 Z9 17 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD APR 26 PY 1991 VL 179 IS 4 BP 374 EP 378 DI 10.1016/0009-2614(91)85169-W PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA FK381 UT WOS:A1991FK38100012 ER PT J AU NEUHAUSER, D JUDSON, RS AF NEUHAUSER, D JUDSON, RS TI REACTIVE SCATTERING USING A MIXED QUANTUM-CLASSICAL PARADIGM SO CHEMICAL PHYSICS LETTERS LA English DT Article ID WAVE PACKET REPRESENTATION; POTENTIAL-ENERGY SURFACE; INTEGRAL CROSS-SECTIONS; DYNAMICS; SYSTEMS; MODEL; H-3 AB A method for performing reactive scattering calculations using mixed quantum/classical dynamics is described. The wavefunction is decomposed into a time-dependent SCF product form. Reactive degrees of freedom are treated quantum mechanically and the rest are treated classically. The wave packet in the quantum degree of freedom is only followed in one arrangement channel to minimize the size of the numerical grid. Parts of the packet that move into other arrangement channels are absorbed using negative imaginary optical potentials. Two variants of the method are tested on the collinear T + HT --> TH + T reaction where they give qualitatively correct predictions of tunneling probabilities near threshold. C1 SANDIA NATL LABS,CTR COMPUTAT ENGN,LIVERMORE,CA 94550. RP NEUHAUSER, D (reprint author), PRINCETON UNIV,DEPT CHEM,PRINCETON,NJ 08544, USA. OI Judson, Richard/0000-0002-2348-9633 NR 32 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD APR 26 PY 1991 VL 179 IS 4 BP 385 EP 392 DI 10.1016/0009-2614(91)85171-R PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA FK381 UT WOS:A1991FK38100014 ER PT J AU GUAY, D TOURILLON, G DARTYGE, E FONTAINE, A MCBREEN, J PANDYA, KI OGRADY, WE AF GUAY, D TOURILLON, G DARTYGE, E FONTAINE, A MCBREEN, J PANDYA, KI OGRADY, WE TI INSITU TIME-RESOLVED EXAFS STUDY OF THE STRUCTURAL MODIFICATIONS OCCURRING IN NICKEL-OXIDE ELECTRODES BETWEEN THEIR FULLY OXIDIZED AND REDUCED STATES SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Article ID X-RAY ABSORPTION; DISPERSIVE MODE; FUEL-CELL; HYDROXIDE; SPECTROSCOPY AB In-situ time-resolved extended X-ray absorption fine structure (EXAFS) spectroscopy at the Ni K-edge was coupled with cyclic voltammetry to investigate the structural changes occurring in nickel hydroxide electrodes between their fully charged and discharged states. On the negative sweep, analysis of the EXAFS data indicated that the reduction process does not involve the formation of a new compound. The appearance of a second cathodic peak in the cyclic voltammogram is best explained as being due to the formation of an electronically insulating barrier surrounding the active material. On the positive sweep, a threshold potential difference between the onset of the anodic current and that of the electronic and structural modifications was observed. This is due to the fact that the oxidation of the incorporated OH- ions occurs prior to that of the Ni compound. C1 BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973. USN,RES LAB,WASHINGTON,DC 20375. RP GUAY, D (reprint author), UNIV PARIS 11,UTILISAT RAYONNEMENT ELECTROMAGNET LAB,BATIMENT 209D,F-91405 ORSAY,FRANCE. OI Guay, Daniel/0000-0001-5057-959X NR 35 TC 14 Z9 14 U1 1 U2 8 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0022-0728 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD APR 25 PY 1991 VL 305 IS 1 BP 83 EP 95 DI 10.1016/0022-0728(91)85204-3 PG 13 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA FQ518 UT WOS:A1991FQ51800007 ER PT J AU FAN, JB KORMAN, SH CANTOR, CR SMITH, CL AF FAN, JB KORMAN, SH CANTOR, CR SMITH, CL TI GIARDIA-LAMBLIA - HAPLOID GENOME SIZE DETERMINED BY PULSED FIELD GEL-ELECTROPHORESIS IS LESS THAN 12-MB SO NUCLEIC ACIDS RESEARCH LA English DT Article ID SCHIZOSACCHAROMYCES-POMBE; RIBOSOMAL-RNA; DNA; RESOLUTION; SEPARATION; REPEAT; MAP AB Previous estimates of the size of the Giardia lamblia genome have ranged from 30 to 80 million base pairs (Mb), based on DNA renaturation kinetics. This is much larger than the sum of the sizes of the 4 to 5 chromosomal DNAs seen in typical pulsed field gel electrophoretic analyses. One possible explanation is that each visible chromosomal DNA consists of several unresolved DNA species. To examine this we have performed quantitative densitometry of ethidium stained chromosomal DNAs and Notl genomic digests. We have also examined the distribution of rDNA on Notl genomic fragments. All of our results suggests that the true genome size is 10.6 to 11.9 Mb. It is conceivable that the previous larger estimates may be distorted by impurities in the DNA preparations used. C1 UNIV CALIF BERKELEY,DEPT MOLEC & CELL BIOL,BERKELEY,CA 94720. HADASSAH UNIV HOSP,DEPT PEDIAT,JERUSALEM,ISRAEL. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CTR HUMAN GENOME,BERKELEY,CA 94720. OI Smith, Cassandra/0000-0002-0346-8907 NR 22 TC 39 Z9 42 U1 0 U2 0 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD APR 25 PY 1991 VL 19 IS 8 BP 1905 EP 1908 DI 10.1093/nar/19.8.1905 PG 4 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA FK282 UT WOS:A1991FK28200026 PM 2030969 ER PT J AU BURKS, C CASSIDY, M CINKOSKY, MJ CUMELLA, KE GILNA, P HAYDEN, JED KEEN, GM KELLEY, TA KELLY, M KRISTOFFERSON, D RYALS, J AF BURKS, C CASSIDY, M CINKOSKY, MJ CUMELLA, KE GILNA, P HAYDEN, JED KEEN, GM KELLEY, TA KELLY, M KRISTOFFERSON, D RYALS, J TI GENBANK SO NUCLEIC ACIDS RESEARCH LA English DT Article ID HUMAN GENOME AB The GenBank nucleotide sequence database now contains sequence data and associated annotation corresponding to 56,000,000 nucleotides in 45,000 entries. The input stream of data coming into the database has largely been shifted to direct submissions from the scientific community on electronic media. The data have been installed in a relational database management system and are made available in this form through on-line access, and through various network and off-line computer-readable media. In addition, GenBank provides the U.S. distribution center for the BIOSCI electronic bulletin board service. C1 INTELLIGENET INC,MT VIEW,CA 94040. RP BURKS, C (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,THEORET BIOL & BIOPHYS GRP,T-10,MS K710,LOS ALAMOS,NM 87545, USA. RI Gilna, Paul/I-3608-2016 OI Gilna, Paul/0000-0002-6542-0191 FU NIGMS NIH HHS [N01-GM-7-2110] NR 23 TC 66 Z9 66 U1 2 U2 2 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD APR 25 PY 1991 VL 19 SU S BP 2221 EP 2225 PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA FM756 UT WOS:A1991FM75600013 PM 2041806 ER PT J AU HOLDOM, B AF HOLDOM, B TI OBLIQUE ELECTROWEAK CORRECTIONS AND AN EXTRA GAUGE BOSON SO PHYSICS LETTERS B LA English DT Article ID PHYSICS AB We develop an effective lagrangian based framework for the inclusion of new heavy physics effects on gauge boson self-energies, various observables may be expressed in terms of the parameters S, T and U. We then generalize this framework to include a new U (1) gauge boson. We treat the effects of mixing through kinetic terms with the Z and the photon as well as mass mixing with the Z. We show how the bulk of these effects produce effective shifts in the parameters S, T and U. C1 FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. RP HOLDOM, B (reprint author), UNIV TORONTO,DEPT PHYS,TORONTO M5S 1A7,ONTARIO,CANADA. NR 14 TC 133 Z9 134 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 25 PY 1991 VL 259 IS 3 BP 329 EP 334 DI 10.1016/0370-2693(91)90836-F PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK648 UT WOS:A1991FK64800017 ER PT J AU WILLENBROCK, S VALENCIA, G AF WILLENBROCK, S VALENCIA, G TI ON THE DEFINITION OF THE Z-BOSON MASS SO PHYSICS LETTERS B LA English DT Article ID ORDER RADIATIVE-CORRECTIONS; LEP ENERGIES AB We propose a physical definition of the Z-boson mass, the real part of the pole in the Z-boson propagator, which is field-redefinition invariant and gauge invariant to all orders. The physical Z-boson mass lies approximately 26 MeV below the commonly used "on-shell" mass. C1 CERN,DIV THEORY,CH-1211 GENEVA 23,SWITZERLAND. RP WILLENBROCK, S (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 33 TC 112 Z9 112 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 25 PY 1991 VL 259 IS 3 BP 373 EP 376 DI 10.1016/0370-2693(91)90843-F PG 4 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK648 UT WOS:A1991FK64800024 ER PT J AU Decamp, D Deschizeaux, B Goy, C Less, JP Minard, MN Alemany, R Crespo, JM Delfino, M Fernandez, E Gaitan, V Garrido, L Mato, P Mir, LM Pacheco, A Catanesi, MG Creanza, D de Palma, M Farilla, A Iaselli, G Maggi, G Maggi, M Natali, S Nuzzo, S Quattromini, M Ranieri, A Raso, G Romano, F Ruggieri, F Selvaggi, G Silvestris, L Tempesta, P Zito, G Gao, Y Hu, H Huang, D Huang, X Lin, J Lou, J Qiao, C Ruan, T Wang, T Xie, Y Xu, D Xu, R Zhang, J Zhao, W Atwood, WB Bird, F Blucher, E Bonvicini, G Bossi, F Brown, D Burnett, TH Drevermann, H Dydak, F Forty, RW Grab, C Hagelberg, R Haywood, A Hilgart, J Jost, B Kasemann, M Knobloch, J Lacourt, A Lancon, C Lehraus, I Lohse, T Marchioro, A Martinez, M May, J Menary, S Minten, A Miotto, A Miquel, R Moser, HG Nash, J Palazzi, P Ranjard, F Redlinger, G Roth, A Rothberg, J Rotscheidt, H St Denis, R Schlatter, D Takashima, M Talby, M Tejessy, W Wachsmuth, H Wasserbaech, S Wheeler, S Wiedenmann, W Witzeling, W Wotschack, J Ajaltouni, A Bardadin-Otwinowska, M Falvard, A El Fellous, R Gay, P Harvey, J Henrard, P Jousset, J Michel, B Montret, JC Pallin, D Perret, P Proriol, J Prulhiere, F Stimpfl, G Hansen, JD Hansen, JR Hansen, PH Mollerud, R Nielsen, ER Nilsson, BS Efthymiopoulos, I Simopoulou, E Vayaki, A Badier, J Blondel, A Bonneaud, G Bourotte, J Braems, F Brient, JC Fouque, G Gamess, A Guirlet, R Orteu, S Rosowsky, A Rouge, A Rumpf, M Tanaka, R Videau, H Candlin, DJ Veitch, E Parrini, G Corden, M Georgiopoulos, C Ikeda, M Lannutti, J Levinthal, D Mermikides, M Sawyer, L Antonelli, A Baldini, R Bencivenni, G Bologna, G Campana, P Capon, G Chiarella, V D'Ettorre-Piazzoli, B Felici, G Laurelli, P Mannocchi, G Massimo-Brancaccio, F Murtas, F Murtas, GP Nicoletti, G Passalacqua, L Pepe-Altarelli, M Picchi, P Zografou, P Altoon, B Boyle, O Halley, AW ten Have, I Hearns, JL Lynch, JG Morton, WT Raine, C Scarr, JM Smith, K Thompson, AS Turnbull, RM Brandl, B Braun, O Geiges, R Geweniger, C Hanke, P Hepp, V Kluge, EE Maumary, Y Putzer, A Rensch, B Stahl, A Tittel, K Wunsch, M Belk, AT Beuselinck, R Binnie, DM Cameron, W Cattaneo, M Dornan, PJ Dugeay, S Greene, AM Hassard, JF Lieske, NM Patton, SJ Payne, DG Phillips, MJ Sedgbeer, JK Taylor, G Tomalin, IR Wright, AG Girtler, P Kuhn, D Rudolph, G Bowdery, CK Brodbeck, TJ Finch, AJ Foster, F Hughes, G Keemer, NR Nuttall, M Patel, A Rowlingson, BS Sloan, T Snow, SW Whelan, EP Barczewski, T Bauerdick, LAT Kleinknecht, K Renk, B Roehn, S Sander, AG Schmelling, M Schmidt, H Steeg, F Albanese, JP Aubert, JJ Benchouk, C Bernard, V Bonissent, A Courvoisier, D Etienne, F Papalexiou, S Payre, P Pietrzyk, B Qian, Z Becker, H Blum, W Cattaneo, P Cowan, G Dehning, B Dietl, H Fernandez-Bosman, M Hansl-Kozanecka, T Jahn, A Kozanecki, W Lange, E Lauber, J Lutjens, G Lutz, G Manner, W Pan, Y Richter, R Schroder, J Schwarz, AS Settles, R Stierlin, U Thomas, J Wolf, G Bertin, V Boucrot, J Callot, O Chen, X Cordier, A Davier, M Ganis, G Grivaz, JF Heusse, P Janot, P Kim, DW Le Diberber, F Lefrancois, J Lutz, AM Veillet, JJ Videau, I Zhang, Z Zomer, F Amendolia, SR Bagliesi, G Bagliesi, G Batignani, G Bosisio, L Bottigli, U Bradaschia, C Carpinelli, M Ciocci, MA Dell'Orso, R Ferrante, I Fidecaro, F Foa, L Focardi, E Forti, F Giassi, A Giorgi, MA Ligabue, F Lusiani, A Mannelli, EB Marrocchesi, PS Messineo, A Moneta, L Palla, F Sanguinetti, G Steinberger, J Tenchini, R Tonelli, G Triggiani, G Viannini, C Venturi, A Verdini, PG Walsh, J Carter, JM Green, MG March, PV Medcalf, T Quazi, IS Saich, MR Strong, JA Thomas, RM West, LR Wildish, T Botterill, DR Clifft, RW Edgecock, TR Edwards, M Fisher, SM Jones, TJ Norton, PR Salmon, DP Thompson, JC Bloch-Devaux, B Colas, P Klopfenstein, C Locci, E Loucatos, S Monnier, E Perez, P Perlas, JA Perrier, F Rander, J Renardy, JF Roussarie, A Schuller, JP Schwindling, J Vallage, B Ashman, JG Booth, CN Buttar, C Carney, R Cartwright, S Combley, F Dinsdale, M Dogru, M Hatfield, F Martin, J Parker, D Reeves, P Thompson, LF Brandt, S Burkhardt, H Grupen, C Meinhard, H Mirabito, L Neugebauer, E Schafer, U Seywerd, H Apollinari, G Giannini, G Gobbo, B Liello, F Rolandi, L Stiegler, U Bellantoni, L Boudreau, JF Cinabro, D Conway, JS Cowen, DF DeWeerd, AJ Feng, Z Ferguson, DPS Gao, YS Grahl, J Harton, JL Jacobsen, JE Jared, RC Johnson, RP LeClaire, BW Pan, YB Pater, JR Saadi, Y Sharma, V Walsh, AM Wear, JA Weber, FV Whitney, MH Sau, LW Zhou, ZL Zobernig, G AF Decamp, D Deschizeaux, B Goy, C Less, JP Minard, MN Alemany, R Crespo, JM Delfino, M Fernandez, E Gaitan, V Garrido, L Mato, P Mir, LM Pacheco, A Catanesi, MG Creanza, D de Palma, M Farilla, A Iaselli, G Maggi, G Maggi, M Natali, S Nuzzo, S Quattromini, M Ranieri, A Raso, G Romano, F Ruggieri, F Selvaggi, G Silvestris, L Tempesta, P Zito, G Gao, Y Hu, H Huang, D Huang, X Lin, J Lou, J Qiao, C Ruan, T Wang, T Xie, Y Xu, D Xu, R Zhang, J Zhao, W Atwood, WB Bird, F Blucher, E Bonvicini, G Bossi, F Brown, D Burnett, TH Drevermann, H Dydak, F Forty, RW Grab, C Hagelberg, R Haywood, A Hilgart, J Jost, B Kasemann, M Knobloch, J Lacourt, A Lancon, C Lehraus, I Lohse, T Marchioro, A Martinez, M May, J Menary, S Minten, A Miotto, A Miquel, R Moser, HG Nash, J Palazzi, P Ranjard, F Redlinger, G Roth, A Rothberg, J Rotscheidt, H St Denis, R Schlatter, D Takashima, M Talby, M Tejessy, W Wachsmuth, H Wasserbaech, S Wheeler, S Wiedenmann, W Witzeling, W Wotschack, J Ajaltouni, A Bardadin-Otwinowska, M Falvard, A El Fellous, R Gay, P Harvey, J Henrard, P Jousset, J Michel, B Montret, JC Pallin, D Perret, P Proriol, J Prulhiere, F Stimpfl, G Hansen, JD Hansen, JR Hansen, PH Mollerud, R Nielsen, ER Nilsson, BS Efthymiopoulos, I Simopoulou, E Vayaki, A Badier, J Blondel, A Bonneaud, G Bourotte, J Braems, F Brient, JC Fouque, G Gamess, A Guirlet, R Orteu, S Rosowsky, A Rouge, A Rumpf, M Tanaka, R Videau, H Candlin, DJ Veitch, E Parrini, G Corden, M Georgiopoulos, C Ikeda, M Lannutti, J Levinthal, D Mermikides, M Sawyer, L Antonelli, A Baldini, R Bencivenni, G Bologna, G Campana, P Capon, G Chiarella, V D'Ettorre-Piazzoli, B Felici, G Laurelli, P Mannocchi, G Massimo-Brancaccio, F Murtas, F Murtas, GP Nicoletti, G Passalacqua, L Pepe-Altarelli, M Picchi, P Zografou, P Altoon, B Boyle, O Halley, AW ten Have, I Hearns, JL Lynch, JG Morton, WT Raine, C Scarr, JM Smith, K Thompson, AS Turnbull, RM Brandl, B Braun, O Geiges, R Geweniger, C Hanke, P Hepp, V Kluge, EE Maumary, Y Putzer, A Rensch, B Stahl, A Tittel, K Wunsch, M Belk, AT Beuselinck, R Binnie, DM Cameron, W Cattaneo, M Dornan, PJ Dugeay, S Greene, AM Hassard, JF Lieske, NM Patton, SJ Payne, DG Phillips, MJ Sedgbeer, JK Taylor, G Tomalin, IR Wright, AG Girtler, P Kuhn, D Rudolph, G Bowdery, CK Brodbeck, TJ Finch, AJ Foster, F Hughes, G Keemer, NR Nuttall, M Patel, A Rowlingson, BS Sloan, T Snow, SW Whelan, EP Barczewski, T Bauerdick, LAT Kleinknecht, K Renk, B Roehn, S Sander, AG Schmelling, M Schmidt, H Steeg, F Albanese, JP Aubert, JJ Benchouk, C Bernard, V Bonissent, A Courvoisier, D Etienne, F Papalexiou, S Payre, P Pietrzyk, B Qian, Z Becker, H Blum, W Cattaneo, P Cowan, G Dehning, B Dietl, H Fernandez-Bosman, M Hansl-Kozanecka, T Jahn, A Kozanecki, W Lange, E Lauber, J Lutjens, G Lutz, G Manner, W Pan, Y Richter, R Schroder, J Schwarz, AS Settles, R Stierlin, U Thomas, J Wolf, G Bertin, V Boucrot, J Callot, O Chen, X Cordier, A Davier, M Ganis, G Grivaz, JF Heusse, P Janot, P Kim, DW Le Diberber, F Lefrancois, J Lutz, AM Veillet, JJ Videau, I Zhang, Z Zomer, F Amendolia, SR Bagliesi, G Bagliesi, G Batignani, G Bosisio, L Bottigli, U Bradaschia, C Carpinelli, M Ciocci, MA Dell'Orso, R Ferrante, I Fidecaro, F Foa, L Focardi, E Forti, F Giassi, A Giorgi, MA Ligabue, F Lusiani, A Mannelli, EB Marrocchesi, PS Messineo, A Moneta, L Palla, F Sanguinetti, G Steinberger, J Tenchini, R Tonelli, G Triggiani, G Viannini, C Venturi, A Verdini, PG Walsh, J Carter, JM Green, MG March, PV Medcalf, T Quazi, IS Saich, MR Strong, JA Thomas, RM West, LR Wildish, T Botterill, DR Clifft, RW Edgecock, TR Edwards, M Fisher, SM Jones, TJ Norton, PR Salmon, DP Thompson, JC Bloch-Devaux, B Colas, P Klopfenstein, C Locci, E Loucatos, S Monnier, E Perez, P Perlas, JA Perrier, F Rander, J Renardy, JF Roussarie, A Schuller, JP Schwindling, J Vallage, B Ashman, JG Booth, CN Buttar, C Carney, R Cartwright, S Combley, F Dinsdale, M Dogru, M Hatfield, F Martin, J Parker, D Reeves, P Thompson, LF Brandt, S Burkhardt, H Grupen, C Meinhard, H Mirabito, L Neugebauer, E Schafer, U Seywerd, H Apollinari, G Giannini, G Gobbo, B Liello, F Rolandi, L Stiegler, U Bellantoni, L Boudreau, JF Cinabro, D Conway, JS Cowen, DF DeWeerd, AJ Feng, Z Ferguson, DPS Gao, YS Grahl, J Harton, JL Jacobsen, JE Jared, RC Johnson, RP LeClaire, BW Pan, YB Pater, JR Saadi, Y Sharma, V Walsh, AM Wear, JA Weber, FV Whitney, MH Sau, LW Zhou, ZL Zobernig, G CA ALEPH Collaboration TI MEASUREMENT OF CHARGE ASYMMETRY IN HADRONIC Z DECAYS SO PHYSICS LETTERS B LA English DT Article ID E+E-ANNIHILATION; QUARK JETS; SCATTERING; EVENTS; PETRA; LEP AB A significant charge asymmetry is observed in the hadronic Z decays collected with the ALEPH detector at LEP. The asymmetry expressed in terms of the difference in momentum weighted charges in the two event hemispheres is measured to be - = - 0.0084 +/- 0.0015 (stat.) +/- 0.0004 (exp. sys.). In the framework of the standard model this can be interpreted as a measurement of the effective electroweak mixing angle, sin2-theta-w(M(z)2) = 0.2300 +/- 0.0034 (stat.) +/- 0.0010 (exp. sys.) +/- 0.0038 (theor. sys.) or of the ratio of the vector to axial-vector coupling constants of the electron, g(v(e))/g(A(e)) = + 0.073 +/- 0.024. C1 CNRS, IN2P3, Lab Phys Particules LAPP, F-74019 Annecy Le Vieux, FRANCE. Univ Autonoma Barcelona, Lab Fis Altas Energias, E-08193 Bellaterra, SPAIN. Ist Nazl Fis Nucl, Sez Bari, I-70126 Bari, ITALY. Univ Bari, Dipartimento Fis, I-70126 Bari, ITALY. Acad Sinica, Inst High Energy Phys, Beijing, PEOPLES R CHINA. European Lab Particle Phys CERN, CH-1211 Geneva 23, SWITZERLAND. Univ Blaise Pascal, CNRS, IN2P3, Lab Phys Corpusculaire, F-63177 Aubiere, FRANCE. Neils Bohr Inst, DK-2100 Copenhagen, DENMARK. NRCD, Athens, GREECE. Ecole Polytech, CNRS, IN2P3, Lab Phys Nucl & Hautes Energies, F-91128 Palaiseau, FRANCE. Univ Edinburgh, Dept Phys, Edinburgh EH9 3JZ, Midlothian, SCOTLAND. Univ Florence, Dept Phys, I-50126 Florence, ITALY. Ist Nazl Fis Nucl, Sez Firenze, I-50125 Florence, ITALY. Florida State Univ, Supercomp Computat Res Inst, Tallahassee, FL 32306 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. Ist Nazl Fis Nucl, LNF, Lab Naz, I-00044 Frascati, ITALY. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, SCOTLAND. Univ Heidelberg, Inst Hochenergiephys, D-6900 Heidelberg, GERMANY. Univ London Sch Pharm, Dept Phys, London SW7 2BZ, ENGLAND. Innsbruck Univ, Inst Expt Phys, A-6020 Innsbruck, AUSTRIA. Univ Lancaster, Dept Phys, Lancaster LA1 4YB, ENGLAND. Univ Mainz, Inst Phys, D-6500 Mainz, GERMANY. CNRS, Fac Sci Luminy, IN2P3, Ctr Phys Particules, F-13288 Marseille, FRANCE. Max Planck Inst Astrophys, Werner Heisenberg Inst Phys, D-8000 Munich, GERMANY. Univ Paris Sud, CNRS, IN2P3, Lab Accelerateur, F-91405 Orsay, FRANCE. Univ Pisa, Dept Fis, INFN, Sez Pisa, I-56010 Pisa, ITALY. Scuola Normale Super Pisa, I-56010 Pisa, ITALY. Univ London, Royal Holloway & Bedford New Coll, Dept Phys, Surrey TW20 OEX, ENGLAND. Rutherford Appleton Lab, Particle Phys Dept, Didcot OX11 OQX, Oxon, ENGLAND. CEN Saclay, Dept Phys Particules Element, F-91191 Gif Sur Yvette, FRANCE. Univ Sheffield, Dept Phys, Sheffield S3 7RH, S Yorkshire, ENGLAND. Univ Siegen, Fachbereich Phys, D-5900 Siegen, GERMANY. Univ Trieste, Dipartimento Fis, I-34127 Trieste, ITALY. Ist Nazl Fis Nucl, Sez Trieste, I-34127 Trieste, ITALY. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. SLAC, Stanford, CA 94309 USA. Univ Washington, Seattle, WA 98195 USA. Ctr Phys Particules, Fac Sci, F-13288 Marseille 9, FRANCE. Univ Turin, Ist Fis Gen, Turin, ITALY. CNR, Ist Cosmogeofis, I-10133 Turin, ITALY. LBL, Berkeley, CA 94720 USA. RP Decamp, D (reprint author), CNRS, IN2P3, Lab Phys Particules LAPP, F-74019 Annecy Le Vieux, FRANCE. RI Murtas, Fabrizio/B-5729-2012; Booth, Christopher/B-5263-2016; Delfino, Manuel/A-1545-2012; Pacheco Pages, Andres/C-5353-2011; Ferrante, Isidoro/F-1017-2012; Ligabue, Franco/F-3432-2014; Lusiani, Alberto/A-3329-2016; Venturi, Andrea/J-1877-2012; Perrier, Frederic/A-5953-2011; Rolandi, Luigi (Gigi)/E-8563-2013; Colas, Paul/F-2876-2013; Bosman, Martine/J-9917-2014; Fernandez, Enrique/L-5387-2014; Mir, Lluisa-Maria/G-7212-2015; ciocci, maria agnese /I-2153-2015; Lusiani, Alberto/N-2976-2015; Marrocchesi, Pier Simone/N-9068-2015; Forti, Francesco/H-3035-2011 OI Booth, Christopher/0000-0002-6051-2847; Delfino, Manuel/0000-0002-9468-4751; Pacheco Pages, Andres/0000-0001-8210-1734; Ferrante, Isidoro/0000-0002-0083-7228; Palazzi, Paolo/0000-0002-4861-391X; RASO, Giuseppe/0000-0002-5660-3711; Bottigli, Ubaldo/0000-0002-0666-3433; Ligabue, Franco/0000-0002-1549-7107; Bloch-Devaux, Brigitte/0000-0002-2463-1232; Murtas, Fabrizio/0000-0002-7041-6541; Garrido Beltran, Lluis/0000-0001-8883-6539; Edgecock, Rob/0000-0002-7896-3312; Miquel, Ramon/0000-0002-6610-4836; Lusiani, Alberto/0000-0002-6876-3288; Rolandi, Luigi (Gigi)/0000-0002-0635-274X; Bosman, Martine/0000-0002-7290-643X; Fernandez, Enrique/0000-0002-6405-9488; Mir, Lluisa-Maria/0000-0002-4276-715X; ciocci, maria agnese /0000-0003-0002-5462; Lusiani, Alberto/0000-0002-6876-3288; Marrocchesi, Pier Simone/0000-0003-1966-140X; Forti, Francesco/0000-0001-6535-7965 NR 28 TC 31 Z9 31 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 25 PY 1991 VL 259 IS 3 BP 377 EP 388 DI 10.1016/0370-2693(91)90844-G PG 12 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FK648 UT WOS:A1991FK64800025 ER PT J AU CREUTZ, C SCHWARZ, HA WISHART, JF FUJITA, E SUTIN, N AF CREUTZ, C SCHWARZ, HA WISHART, JF FUJITA, E SUTIN, N TI THERMODYNAMICS AND KINETICS OF CARBON-DIOXIDE BINDING TO 2 STEREOISOMERS OF A COBALT(I) MACROCYCLE IN AQUEOUS-SOLUTION SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID FREE-RADICALS; HOMOGENEOUS CATALYSIS; PULSE-RADIOLYSIS; AMINE COMPLEXES; VISIBLE-LIGHT; REDUCTION; LIGANDS; CO2; BONDS; SYSTEM AB The thermodynamics and kinetics of binding of CO2, CO, and H+ to N-racemic and N-meso stereoisomers of the cobalt(I) macrocycle CoL+ (L = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene) have been determined in aqueous media with use of the pulse radiolysis technique and transient ultraviolet-visible spectroscopy. N-rac- or N-meso-CoL+ was produced by the hydrated electron reduction of N-rac- or N-meso-CoL2+, with tert-butyl alcohol generally added to scavenge hydroxyl radicals. Reactions of both N-rac- and N-meso CoL+ are readily followed by the disappearance of intense (epsilon-1 x 10(4) M-1 cm-1) absorption bands at 630 and 635 nm, respectively. The product absorptions are much less intense (epsilon-200-500 M-1 cm-1) and shifted to higher energy (400-500 nm). Carbon dioxide adducts were also produced via the reactions of N-rac- or N-meso-CoL2+ with formate radical .CO2- in solutions containing sodium formate and CO2 and hydrogen ion adducts (hydrides) by the reactions with .H atom in acid solution. The known stereochemistry of the methyl radical additions to N-rac- and N-meso-CoL2+ was used to asign the different isomers of the adducts. Thus, reaction of .H and .CO2- with N-rac-CoL2+ yields sec-N-rac-CoL(H)2+ and sec-N-rac-CoL(CO2)+, respectively, and the reaction of N-rac-CoL+ with H+ and CO2 yields prim-N-rac-CoL(H)2+ and prim-N-rac-CoL(CO2)+, respectively. As expected, only N-meso adducts are obtained from either N-meso-CoL+ or N-meso-CoL2+. Formation constants for the complexes (determined by analysis of equilibrium absorption or equilibration kinetics) at 25-degrees-C are CoL(CO2)+, 2.5 x 10(8) M-1 (prim-N-rac), 6.0 x 10(6) M-1 (N-meso); CoL(CO)+, 1.6 x 10(8) M-1 (prim-N-rac), 0.8 x 10(8) M-1 (N-meso); CoL(H)2+, 2.5 x 10(11) M-1 (prim-N-rac), greater-than-or-equal-to 7.9 x 10(13) M-1 (N-meso). The rate constants are large and generally parallel the stability of the adduct. The following are values of k (M-1 s-1) for addition at 25-degrees-C: CO2, 1.7 x 10(8) (prim-N-rac), 1.5 x 10(7) (N-meso); CO, 5.0 x 10(8) (prim-N-rac), 8.3 x 10(8) (N-meso); H+, 3.0 x 10(9) (prim-N-rac), 2.3 x 10(9) (N-meso). RP CREUTZ, C (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. RI Fujita, Etsuko/D-8814-2013; Wishart, James/L-6303-2013 OI Wishart, James/0000-0002-0488-7636 NR 43 TC 53 Z9 53 U1 1 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD APR 24 PY 1991 VL 113 IS 9 BP 3361 EP 3371 DI 10.1021/ja00009a022 PG 11 WC Chemistry, Multidisciplinary SC Chemistry GA FJ121 UT WOS:A1991FJ12100022 ER PT J AU HARTWIG, JF BERGMAN, RG ANDERSEN, RA AF HARTWIG, JF BERGMAN, RG ANDERSEN, RA TI STRUCTURE, SYNTHESIS, AND CHEMISTRY OF (PME3)4RU(ETA-2-BENZYNE) - REACTIONS WITH ARENES, ALKENES, AND HETEROATOM-CONTAINING ORGANIC-COMPOUNDS - SYNTHESIS AND STRUCTURE OF A MONOMERIC HYDROXIDE COMPLEX SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID C-H ACTIVATION; TRANSITION-METAL ALKOXIDES; RAY CRYSTAL-STRUCTURES; X-RAY; THERMAL-DECOMPOSITION; N-H; HYDRIDE COMPLEXES; KETENE COMPLEXES; MOLECULAR-STRUCTURE; BENZYNE COMPLEX AB Thermolysis of (PMe3)4Ru(Ph)(Me) or (PMe3)4Ru(Ph)2 leads to the ruthenium benzyne complex (PMe3)4Ru(eta-2-C6H4) (1) by a mechanism that involves initial reversible dissociation of phosphine. In many ways, its chemistry is analogous to that of early rather than late organo-transition-metal complexes. Thus, compound 1 undergoes apparent sigma-bond metathesis reactions with the C-H bonds of benzene or toluene solvent (the reverse of the formation of 1), the N-H bond in aniline, and O-H bonds of p-cresol, 2-propanol, and water. The monomeric hydroxide complex resulting from addition of water has been structurally characterized. Compound 1 also undergoes insertion reactions with a variety of unsaturated organic molecules, including ethylene, di-p-tolylacetylene, benzaldehyde, and benzonitrile. Qualitative mechanistic studies on the O-H addition of p-cresol and the insertion of benzaldehyde and benzonitrile are reported. C1 UNIV CALIF BERKELEY, DEPT CHEM, BERKELEY, CA 94720 USA. LAWRENCE BERKELEY LAB, DIV MAT & CHEM SCI, BERKELEY, CA 94720 USA. NR 85 TC 73 Z9 73 U1 0 U2 5 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 APR 24 PY 1991 VL 113 IS 9 BP 3404 EP 3418 DI 10.1021/ja00009a028 PG 15 WC Chemistry, Multidisciplinary SC Chemistry GA FJ121 UT WOS:A1991FJ12100028 ER PT J AU NAKAGAWA, KH INOUYE, C HEDMAN, B KARIN, M TULLIUS, TD HODGSON, KO AF NAKAGAWA, KH INOUYE, C HEDMAN, B KARIN, M TULLIUS, TD HODGSON, KO TI EVIDENCE FROM EXAFS FOR A COPPER CLUSTER IN THE METALLOREGULATORY PROTEIN CUP2 FROM YEAST SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Note ID X-RAY-ABSORPTION; DNA-BINDING PROTEIN; FINE-STRUCTURE; METALLOTHIONEIN GENE; MOLECULAR-STRUCTURES; COORDINATION; EXPRESSION; CRYSTAL; TRANSCRIPTION; DIANIONS C1 STANFORD UNIV,DEPT CHEM,STANFORD,CA 94305. UNIV CALIF SAN DIEGO,SCH MED,SCH MED,DEPT PHARMACOL,LA JOLLA,CA 92093. STANFORD UNIV,SLAC,STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94309. JOHNS HOPKINS UNIV,DEPT CHEM,BALTIMORE,MD 21218. RI Tullius, Thomas/A-9685-2008 OI Tullius, Thomas/0000-0003-4425-796X NR 28 TC 29 Z9 29 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD APR 24 PY 1991 VL 113 IS 9 BP 3621 EP 3623 DI 10.1021/ja00009a075 PG 3 WC Chemistry, Multidisciplinary SC Chemistry GA FJ121 UT WOS:A1991FJ12100075 ER PT J AU MYLES, GM HEARST, JE SANCAR, A AF MYLES, GM HEARST, JE SANCAR, A TI SITE-SPECIFIC MUTAGENESIS OF CONSERVED RESIDUES WITHIN WALKER A-SEQUENCE AND B-SEQUENCE OF ESCHERICHIA-COLI UVRA PROTEIN SO BIOCHEMISTRY LA English DT Article ID NUCLEOTIDE-BINDING DOMAIN; DIRECTED MUTAGENESIS; ADENYLATE KINASE; EXCISION REPAIR; BETA-SUBUNIT; RHO-PROTEIN; DNA; ATP; F1-ATPASE; ENZYME AB UvrA is the ATPase subunit of the DNA repair enzyme (A)BC excinuclease. The amino acid sequence of this protein has revealed, in addition to two zinc fingers, three pairs of nucleotide binding motifs each consisting of a Walker A and B sequence. We have conducted site-specific mutagenesis, ATPase kinetic analyses, and nucleotide binding equilibrium measurements to correlate these sequence motifs with activity. Replacement of the invariant Lys by Ala in the putative A sequences indicated that K37 and K646 but not K353 are involved in ATP hydrolysis. In contrast, substitution of the invariant Asp by Asn in the B sequences at positions D238, D513, or D857 had little effect on the in vivo activity of the protein. Nucleotide binding studies revealed a stoichiometry of 0.5 ADP/UvrA monomer while kinetic measurements on wild-type and mutant proteins showed that the active form of UvrA is a dimer with 2 catalytic sites which interact in a positive cooperative manner in the presence of ADP; mutagenesis of K37 but not of K646 attenuated this cooperativity. Loss of ATPase activity was about 75% in the K37A, 86% in the K646A mutant, and 95% in the K37A-K646A double mutant. These amino acid substitutions had only a marginal effect on the specific binding of UvrA to damaged DNA but drastically reduced its ability to deliver UvrB to the damage site. We find that the deficient UvrB loading activity of these mutant UvrA proteins results from their inability to associate with UvrB in the form of (UvrA)2(UvrB)1 complexes. We conclude that UvrA forms a dimer with two ATPase domains involving K37 and K646 and that the work performed by ATP hydrolysis is the delivery of UvrB to the damage site on DNA. C1 UNIV N CAROLINA,SCH MED,DEPT BIOCHEM & BIOPHYS,CHAPEL HILL,NC 27599. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DEPT CHEM,BERKELEY,CA 94720. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV CHEM BIODYNAM,BERKELEY,CA 94720. FU NIGMS NIH HHS [GM32833] NR 48 TC 55 Z9 55 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD APR 23 PY 1991 VL 30 IS 16 BP 3824 EP 3834 DI 10.1021/bi00230a004 PG 11 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA FH876 UT WOS:A1991FH87600004 PM 1826850 ER PT J AU RAMAKRISHNAN, V PATTHY, L MANGEL, WF AF RAMAKRISHNAN, V PATTHY, L MANGEL, WF TI CONFORMATION OF LYS-PLASMINOGEN AND THE KRINGLE 1-3 FRAGMENT OF PLASMINOGEN ANALYZED BY SMALL-ANGLE NEUTRON-SCATTERING SO BIOCHEMISTRY LA English DT Article ID ANTIFIBRINOLYTIC AMINO-ACIDS; BINDING SITES; NATIVE GLU; ACTIVATION; UROKINASE; FIBRIN; EXISTENCE; PROTEASES; MECHANISM; AFFINITY AB Native human Glu-plasminogen (Glu1-Asn791) was previously shown to have a radius of gyration of 39 angstrom and a shape best described by a prolate ellipsoid [Mangel, W. F., Lin, B., & Ramakrishnan, V. (1990) Science 248, 69-73]. Upon occupation of a weak lysine-binding site, the shape reversibly changes to that best described by a Debye random coil with a radius of gyration of 56 angstrom. Conversion from the closed to the open form is not accompanied by any change in secondary structure, hence the closed conformation is formed by interaction between domains, the five kringles and the protease domain, and this is abolished upon conversion to the open form. Here we analyzed by small-angle neutron scattering the conformations of human Lys-plasminogen (Lys78-Asn791) and the fragment K1-3 that contains the first three kringles of plasminogen (Tyr80-Val338 or Tyr80-Val354). The shape of Lys-plasminogen was best described by a Debye random coil with a radius of gyration of 51 angstrom, and occupation of its lysine-binding sites by 6-aminohexanoic acid did not dramatically alter its conformation. Thus Lys-plasminogen was in the open form, similar to that of Glu-plasminogen with its lysine-binding sites occupied. The fragment K1-3 in the absence or presence of 6-aminohexanoic acid had a shape best described equally either by an elongated prolate ellipsoid or by a Debye random coil, with a radius of gyration of 29 angstrom. Our model for the two forms of plasminogen is that, in the closed form, domain interaction generates a compact, almost globular, structure. Upon ligand binding or removal of the NH2-terminal peptide (Glu1-Lys77), domain interaction is abolished, but the domains remain intact. Flexibility in the polypeptide chains between the domains then gives rise to the extended and flexible structure that is characteristic of the open form. The structural differences between the closed and open forms of plasminogen are discussed in terms of functional differences relevant to the regulation of plasminogen activation. C1 BROOKHAVEN NATL LAB,DEPT BIOL,CTR STRUCT BIOL,UPTON,NY 11973. HUNGARIAN ACAD SCI,BIOL RES CTR,INST ENZYMOL,H-1361 BUDAPEST 5,HUNGARY. RI Patthy, Laszlo/A-2353-2013; OI Ramakrishnan, V/0000-0002-4699-2194 NR 58 TC 36 Z9 36 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD APR 23 PY 1991 VL 30 IS 16 BP 3963 EP 3969 DI 10.1021/bi00230a023 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA FH876 UT WOS:A1991FH87600023 PM 2018765 ER PT J AU COUGHLAN, SJ DAVENPORT, JW HIND, G AF COUGHLAN, SJ DAVENPORT, JW HIND, G TI REACTIVE BLUE-2 IS A POTENT INHIBITOR OF A THYLAKOID PROTEIN-KINASE SO EUROPEAN JOURNAL OF BIOCHEMISTRY LA English DT Article ID AFFINITY-CHROMATOGRAPHY; PHOSPHORYLATION; COMPLEX; PURIFICATION; CHARGE; DYES AB The anthraquinone dye reactive blue 2 was found to be a potent inhibitor of a protein kinase isolated and purified from thylakoids. This enzyme was also inhibited in situ, with corresponding inhibition of ATP-dependent quenching of the chlorophyll fluorescence. The mode of inhibition was noncompetitive, with a K(i) of 8-mu-M for the membrane-bound kinase, and 6-mu-M for the purified kinase. The inhibitor did not modify the substrate preference of the endogeneous kinase and could be removed from the membrane by washing. Unlike reactive blue 2, the enzyme did not partition into detergent micelles and is therefore presumably not a hydrophobic, intrinsic membrane protein. RP COUGHLAN, SJ (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. NR 22 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0014-2956 J9 EUR J BIOCHEM JI Eur. J. Biochem. PD APR 23 PY 1991 VL 197 IS 2 BP 467 EP 471 DI 10.1111/j.1432-1033.1991.tb15933.x PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA FJ393 UT WOS:A1991FJ39300024 PM 2026169 ER PT J AU WONG, KS HAN, SG VARDENY, ZV SHINAR, J PANG, Y IJADIMAGHSOODI, S BARTON, TJ GRIGORAS, S PARBHOO, B AF WONG, KS HAN, SG VARDENY, ZV SHINAR, J PANG, Y IJADIMAGHSOODI, S BARTON, TJ GRIGORAS, S PARBHOO, B TI FEMTOSECOND DYNAMICS OF THE NONLINEAR OPTICAL-RESPONSE IN POLYDIETHYNYLSILANE SO APPLIED PHYSICS LETTERS LA English DT Article ID POLYMERS; EXCITATIONS AB We have measured the femtosecond dynamics of the nonlinear optical response chi(3) in polydiethynylsilane (C4H2SiBu2)x, a novel class of pi-conjugated polymers incorporating Si, using degenerate four-wave mixing and photoinduced absorption techniques. In resonance conditions at 620 nm we found chi(3) = 3 X 10(-9) esu, which decays in a record time of 135 fs, followed by a slower decay component of 750 fs, without a long tail even at high laser intensities. This material is an excellent candidate for nonlinear optical devices in the sub-THz frequency range. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,DEPT PHYS,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,DEPT CHEM,AMES,IA 50011. DOW CORNING CORP,MIDLAND,MI 48686. RP WONG, KS (reprint author), UNIV UTAH,DEPT PHYS,SALT LAKE CITY,UT 84112, USA. NR 20 TC 38 Z9 39 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 22 PY 1991 VL 58 IS 16 BP 1695 EP 1697 DI 10.1063/1.105111 PG 3 WC Physics, Applied SC Physics GA FH097 UT WOS:A1991FH09700001 ER PT J AU SCHWARTZ, DT MULLER, RH AF SCHWARTZ, DT MULLER, RH TI PHOTOELECTROCHEMICAL EVIDENCE FOR SATURATED OPTICAL-ABSORPTION IN ELECTROLYTIC CUPROUS-OXIDE SO APPLIED PHYSICS LETTERS LA English DT Article ID ALKALINE-SOLUTIONS; ANODIC FILMS; COPPER; SPECTROSCOPY; ELECTRODES AB An illuminated cuprous oxide-covered electrode immersed in alkaline media exhibits a nonlinear dependence of photocurrent on the intensity of 488 nm laser illumination. Results from intensity modulation experiments show that the differential efficiency for converting photons to photocurrent in the p-type cuprous oxide thin film is inversely proportional to the square root of illumination intensity. A charge transfer model that includes intensity dependent optical absorption in the cuprous oxide layer is found to be consistent with the observed photocurrent response. Analysis of the experimental results using the charge transfer model shows that the saturation intensity for cuprous oxide is approximately 100 mW/cm2. Photoelectrochemical charge transfer is found to be efficient in the potential region where the nonlinear photocurrent response is observed, with nearly all photoinjected minority carriers being consumed by the interfacial charge transfer reaction rather than by recombination. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. RP SCHWARTZ, DT (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720, USA. NR 12 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 22 PY 1991 VL 58 IS 16 BP 1739 EP 1741 DI 10.1063/1.105126 PG 3 WC Physics, Applied SC Physics GA FH097 UT WOS:A1991FH09700016 ER PT J AU ASHLEY, JC AF ASHLEY, JC TI OPTICAL-DATA MODEL FOR THE STOPPING POWER OF CONDENSED MATTER FOR PROTONS AND ANTIPROTONS SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID SWIFT CHARGED-PARTICLES; MEAN EXCITATION-ENERGY; X-RAY REGION; INELASTIC-COLLISIONS; FREE PATHS; AL; CU; POLYSTYRENE; AG; AU AB A model for the energy-loss function of a medium that is based on optical data (approximately zero momentum transfer) and a quadratic extension into the momentum-transfer plane is used to evaluate the stopping power of the medium for portons and antiprotons. Energies less than approximately 40 MeV are considered for which radiative energy losses and density-effect corrections are negligible. 'Higher-order' corrections to the stopping power proportional to the incident particle charge to the third power, Barkas effect, and to the fourth power, Bloch correction, are included. Calculations are presented for aluminum, carbon, copper and polystyrene. Comparisons with experimental data indicate that the optical-data model, plus higher-order corrections, provides an excellent description of energy loss for proton energies from approximately 100 keV to several tens of MeV. RP ASHLEY, JC (reprint author), OAK RIDGE NATL LAB, DIV HLTH & SAFETY RES, OAK RIDGE, TN 37831 USA. NR 37 TC 32 Z9 32 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD APR 22 PY 1991 VL 3 IS 16 BP 2741 EP 2753 DI 10.1088/0953-8984/3/16/014 PG 13 WC Physics, Condensed Matter SC Physics GA FJ541 UT WOS:A1991FJ54100014 ER PT J AU FROYEN, S ZUNGER, A AF FROYEN, S ZUNGER, A TI SURFACE-INDUCED ORDERING IN GAINP SO PHYSICAL REVIEW LETTERS LA English DT Article ID ALLOY SEMICONDUCTORS; PHASE AB Ga0.5In0.5P alloys order spontaneously during growth into a (111) monolayer superlattice despite the fact that this is not the lowest-energy structure of the three-dimensional bulk compound. Using first-principles total-energy calculations, we show that a novel electronically driven surface reconstruction provides a driving force for such ordering. RP FROYEN, S (reprint author), SOLAR ENERGY RES INST,GOLDEN,CO 80401, USA. RI Zunger, Alex/A-6733-2013 NR 20 TC 114 Z9 114 U1 0 U2 5 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 APR 22 PY 1991 VL 66 IS 16 BP 2132 EP 2135 DI 10.1103/PhysRevLett.66.2132 PG 4 WC Physics, Multidisciplinary SC Physics GA FH366 UT WOS:A1991FH36600021 ER PT J AU DESSAU, DS WELLS, BO SHEN, ZX SPICER, WE ARKO, AJ LIST, RS MITZI, DB KAPITULNIK, A AF DESSAU, DS WELLS, BO SHEN, ZX SPICER, WE ARKO, AJ LIST, RS MITZI, DB KAPITULNIK, A TI ANOMALOUS SPECTRAL WEIGHT TRANSFER AT THE SUPERCONDUCTING TRANSITION OF BI2SR2CACU2O8+DELTA SO PHYSICAL REVIEW LETTERS LA English DT Article ID CA-CU-O; SINGLE-CRYSTALS; PHOTOEMISSION; GAP AB Anomalous spectral weight transfer at the superconducting transition of single-crystalline Bi2Sr2CaCu2O8+delta was observed by high-resolution angle-resolved photoemission spectroscopy. As the sample goes superconducting, not only is there spectral weight transfer from the gap region to the pileup peak as in BCS theory, but along the GAMMA-MBAR direction there is also some spectral weight transfer from higher binding energies in the form of a dip. In addition, we note that at the superconducting transition there is a decrease (increase) in the occupied spectral weight for the spectra taken along GAMMA-MBAR (GAMMA-X). C1 UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. STANFORD UNIV,DEPT APPL PHYS,STANFORD,CA 94305. RP DESSAU, DS (reprint author), STANFORD UNIV,STANFORD ELECTR LABS,STANFORD,CA 94305, USA. RI Mitzi, David/B-6260-2012 OI Mitzi, David/0000-0001-5189-4612 NR 16 TC 213 Z9 214 U1 1 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 22 PY 1991 VL 66 IS 16 BP 2160 EP 2163 DI 10.1103/PhysRevLett.66.2160 PG 4 WC Physics, Multidisciplinary SC Physics GA FH366 UT WOS:A1991FH36600028 ER PT J AU BRICENO, G CROMMIE, MF ZETTL, A AF BRICENO, G CROMMIE, MF ZETTL, A TI GIANT OUT-OF-PLANE MAGNETORESISTANCE IN BI-SR-CA-CU-O - A NEW DISSIPATION MECHANISM IN COPPER-OXIDE SUPERCONDUCTORS SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; RESISTIVE TRANSITION; FLUX CREEP; FIELD; DEPENDENCE; CRYSTALS; STATE AB We have measured the anisotropic magnetoresistivity tensor of single-crystal Bi2Sr2CaCu2O8 in the normal and mixed states. For magnetic fields applied perpendicular to the Cu-O (a-b) planes, the out-of-plane (c-axis) resistivity displays a huge magnetic enhancement, and a large apparent depression in the resistively measured transition temperature T(c)(c axis). No such depression is observed in T(c)(a-b plane). Although these results suggest a field-induced anisotropy in T(c), we propose an alternate model of novel Lorentz-force-independent fluctuation-induced dissipation in the mixed state. The model may also account for the anomalous anisotropic magnetoresistance seen in layered low-T(c) superconductors. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP BRICENO, G (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Zettl, Alex/O-4925-2016 OI Zettl, Alex/0000-0001-6330-136X NR 21 TC 168 Z9 168 U1 2 U2 7 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 APR 22 PY 1991 VL 66 IS 16 BP 2164 EP 2167 DI 10.1103/PhysRevLett.66.2164 PG 4 WC Physics, Multidisciplinary SC Physics GA FH366 UT WOS:A1991FH36600029 ER PT J AU ZAK, J AF ZAK, J TI GEOMETRIC PHASE IN MAGNETOOPTIC FARADAY-ROTATION SO PHYSICS LETTERS A LA English DT Article ID BERRY TOPOLOGICAL PHASE; MANIFESTATION; EVOLUTION; HOLONOMY; LIGHT AB The geometric phase is determined for the Faraday rotation. In the Faraday process the wave propagation direction is fixed, while the polarization of the light is rotated by the magneto-optic activity of the medium. Correspondingly, it is shown that the geometric phase equals pi when the polarization vector is transported by a full cycle on the equator of the Poincare sphere. The Faraday rotation turns out to be a complete optical analogue of a spin-1/2 particle in a magnetic field. C1 TECHNION ISRAEL INST TECHNOL,DEPT PHYS,HAIFA,ISRAEL. RP ZAK, J (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. NR 28 TC 5 Z9 5 U1 1 U2 1 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 APR 22 PY 1991 VL 154 IS 9 BP 471 EP 474 DI 10.1016/0375-9601(91)90976-F PG 4 WC Physics, Multidisciplinary SC Physics GA FJ607 UT WOS:A1991FJ60700009 ER PT J AU CHEN, HY ISKANDER, MF PENNER, JE AF CHEN, HY ISKANDER, MF PENNER, JE TI EMPIRICAL-FORMULA FOR OPTICAL-ABSORPTION BY FRACTAL AEROSOL AGGLOMERATES SO APPLIED OPTICS LA English DT Article ID NUCLEAR WINTER; SCATTERING; SMOKE AB An empirical formula for calculating the optical absorption of fractal aerosol agglomerates over a broad frequency range is derived based on extensive calculations made on five smoke agglomerates having a widely varying number of particles ranging from 12 to 372 and an almost constant fractal dimension in the 1.7-1.9 range. The expansion coefficients in the empirical formula were determined by least-squares curve fiting of numerical data obtained using the volume integral equation formulation (VIEF).1 The formula satisfies the frequency dependence of the absorption at lower frequencies and up to the resonance frequency of the agglomerate. Expressions for the resonance frequency (f(o)), as well as the constant coefficients in the empiricial formula, are derived in terms of the structural dimensions, number and size of the primary particles, and the complex permittivity of the aerosol agglomerate. Numerical results obtained from the empirical formula are generally in good agreement with those calculated by the VIEF for soot particles with a magnitude of complex permittivity \epsilon*\ in the 1-7 range. The average error in the absorption calculation is < 5%. The formula thus provides a simple and inexpensive method for calculating the optical absorption of aerosol agglomerates, which otherwise require complicated and expensive methods of calculation. This formula also facilitates the implementation of the accurate VIEF results in large climate codes such as the general circulation model. C1 UNIV UTAH,DEPT ELECT ENGN,SALT LAKE CITY,UT 84112. RP CHEN, HY (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,POB 808,LIVERMORE,CA 94550, USA. RI Penner, Joyce/J-1719-2012 NR 16 TC 6 Z9 6 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD APR 20 PY 1991 VL 30 IS 12 BP 1547 EP 1551 PG 5 WC Optics SC Optics GA FJ906 UT WOS:A1991FJ90600018 PM 20700317 ER PT J AU MCCARTHY, PJ VANBREUGEL, W KAPAHI, VK AF MCCARTHY, PJ VANBREUGEL, W KAPAHI, VK TI CORRELATED RADIO AND OPTICAL ASYMMETRIES IN POWERFUL RADIO-SOURCES SO ASTROPHYSICAL JOURNAL LA English DT Article DE QUASARS; RADIO SOURCES, EXTENDED ID LINE-EMITTING GAS; VLA-OBSERVATIONS; MULTIFREQUENCY OBSERVATIONS; REPRESENTATIVE SAMPLE; 5-KM TELESCOPE; HOST GALAXY; EMISSION; QUASARS; EVOLUTION; JETS AB We examine the spatial distributions of thermal emission-line gas and nonthermal radio-emitting plasma in powerful radio galaxies. At high redshifts and luminosities, the thermal gas is distributed very asymmetrically with respect to the galaxy nucleus. The one-sidedness of the emission line regions is clear evidence of an intrinsically asymmetric property of powerful radio sources. The radio sources are more asymmetric in their lobe spacings at high redshifts, but not at a highly significant level. The primary result of this investigation is that the extended optical line emission is brightest on the side of the closer of the two radio lobes in essentially all cases. This correlation appears to be largely independent of linear size, lobe flux density, redshift, and radio power. A preliminary investigation of lobe-dominated quasars reveals similar correlated radio and optical asymmetries. This demonstrates that the lobe distance asymmetries and the presence of thermal line-emitting gas are directly linked and provides the first direct evidence that environmental effects are responsible for the structural asymmetries of powerful radio sources. The implications for the classical light travel time determination of lobe advance speeds and the derived source ages are briefly discussed. C1 UNIV CALIF BERKELEY, DEPT ASTRON, BERKELEY, CA 94720 USA. UNIV CALIF LAWRENCE LIVERMORE NATL LAB, INST GEOPHYS & PLANETARY PHYS, LIVERMORE, CA 94550 USA. UNIV POONA, TATA INST FUNDAMENTAL RES, POONA 411007, MAHARASHTRA, INDIA. RP MCCARTHY, PJ (reprint author), CARNEGIE INST WASHINGTON OBSERV, PASADENA, CA 91103 USA. NR 95 TC 162 Z9 162 U1 0 U2 5 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 APR 20 PY 1991 VL 371 IS 2 BP 478 EP 490 DI 10.1086/169911 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FF983 UT WOS:A1991FF98300003 ER PT J AU FESEN, RA BECKER, RH AF FESEN, RA BECKER, RH TI NEW CLUES TO THE CASSIOPEIA A SUPERNOVA PROGENITOR SO ASTROPHYSICAL JOURNAL LA English DT Article DE NEBULAE, INDIVIDUAL (CASSIOPEIA-A); NEBULAE, STRUCTURE; NEBULAE, SUPERNOVA REMNANTS ID WOLF-RAYET STARS; IB SUPERNOVAE; NOVA REMNANT; LIGHT CURVES; MASS-LOSS; EVOLUTION; VELOCITY; DIAGRAM; EJECTA AB Optical spectra of filaments in Cas A's northeastern ejecta jet reveal one knot which exhibits the H-alpha and [N II] emissions like those seen in the remnant's quasi-stationary flocculi plus [O I], [O III], and [S II] emissions like those of the remnant's fast-moving knots. Discovery of this chemically peculiar knot suggests that some turbulent mixing may have occurred in the remnant's jet between underlying O and S-rich gas and surface layer material. The mixed ejecta knot's composition further suggests that at the time of its supernova outburst the Cas A progenitor possessed a thin outer layer of hydrogen. The presence of photospheric hydrogen sets an important constraint on the evolutionary phase of this remnant's probable Wolf-Rayet progenitor and means that the Cas A supernova could have briefly displayed H-alpha emission at early phases like that seen for SN 1987K. C1 UNIV COLORADO,CTR ASTROPHYS & SPACE ASTRON,BOULDER,CO 80309. UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616. UNIV CALIF LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550. RP FESEN, RA (reprint author), DARTMOUTH COLL,DEPT PHYS & ASTRON,WILDER LAB,HANOVER,NH 03755, USA. NR 33 TC 43 Z9 43 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1991 VL 371 IS 2 BP 621 EP & DI 10.1086/169926 PN 1 PG 0 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FF983 UT WOS:A1991FF98300018 ER PT J AU BROWN, LE DEARBORN, DS SCHRAMM, DN LARSEN, JT KUROKAWA, S AF BROWN, LE DEARBORN, DS SCHRAMM, DN LARSEN, JT KUROKAWA, S TI THE SHOCK PROCESS AND LIGHT-ELEMENT PRODUCTION IN SUPERNOVA ENVELOPES SO ASTROPHYSICAL JOURNAL LA English DT Article DE NUCLEOSYNTHESIS; SHOCK WAVES; STARS, INTERIORS; STARS, SUPERNOVAE ID LITHIUM; STARS; NUCLEOSYNTHESIS; RATES; ORIGIN; LI AB Detailed hydrodynamic modeling of the passage of supernova shocks through the hydrogen envelopes of blue and red progenitor stars has been carried out to explore the sensitivity to model conditions of light-element production (specifically Li-7 and B-11) which was noted by Dearborn and coworkers. It is found that, for stellar models with M less-than-or-similar-to 100 M., current state-of-the-art supernova shocks do not produce significant light-element yields by hydrodynamic processes alone. The dependence of this conclusion on stellar models and on shock strengths is explored. Preliminary implications for Galactic evolution of lithium are discussed, and it is suspected that intermediate-mass red giant stars may be the most consistent production site for lithium. C1 UNIV CHICAGO,DEPT PHYS & ASTRON,CHICAGO,IL 60637. FERMI NATL ACCELERATOR LAB,NASA,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. UNIV CALIF LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. CASCADE APPL SCI,BOULDER,CO 80306. NR 36 TC 10 Z9 10 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1991 VL 371 IS 2 BP 648 EP 664 DI 10.1086/169931 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FF983 UT WOS:A1991FF98300023 ER PT J AU PARK, MG MILLER, GS AF PARK, MG MILLER, GS TI NEAR-CRITICAL SPHERICAL ACCRETION BY NEUTRON-STARS - GENERAL RELATIVISTIC TREATMENT SO ASTROPHYSICAL JOURNAL LA English DT Article DE HYDRODYNAMICS; RELATIVITY; STARS, ACCRETION; STARS, NEUTRON ID SUPERCRITICAL ACCRETION; RADIATIVE TRANSFER; EDDINGTON LIMIT; BLACK-HOLES; SYSTEMS; QUASARS AB Time-independent spherical accretion by a neutron star is studied using general relativistic radiation hydrodynamics. Numerical integrations of the flow equations are presented. These show that when the luminosity is sufficiently close to (but below) the Eddington limit, the flow velocity increases with decreasing radius far from the neutron star, reaches a maximum at an intermediate radius, and decreases at small radii. A large fraction of the binding energy of the flow is transferred to the radiation through scattering before the flow strikes the surface of the neutron star. Following Miller's treatment of accretion at luminosities near the Eddington limit (which neglected general relativistic effects), we derive analytic approximations for the decelerating phase of the flow's velocity profile. The dependence of the solutions on the variable Eddington factor prescription chosen to close the radiation moment equations is also examined. C1 UNIV ILLINOIS,DEPT PHYS,URBANA,IL 61801. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. NR 32 TC 25 Z9 25 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1991 VL 371 IS 2 BP 708 EP 718 DI 10.1086/169936 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FF983 UT WOS:A1991FF98300028 ER PT J AU IGLESIAS, CA ROGERS, FJ AF IGLESIAS, CA ROGERS, FJ TI OPACITY TABLES FOR CEPHEID VARIABLES SO ASTROPHYSICAL JOURNAL LA English DT Article DE OPACITIES; STARS, PULSATION AB An attractive explanation of discrepancies between observations and theories of Cepheid variables has been the hypothesis of enhanced opacities. Here, new opacity tables for Population I and Population II stars computed using the OPAL code are presented. The tables are organized differently from previous work. Instead of rows and columns of constant temperature and density, the tables follow tracks of constant R = density/(temperature). 3 The results show significant opacity increases for temperatures and densities relevant to stellar pulsation models. RP IGLESIAS, CA (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,L-296,POB 808,LIVERMORE,CA 94550, USA. NR 20 TC 113 Z9 113 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1991 VL 371 IS 2 BP L73 EP L75 DI 10.1086/186005 PN 2 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA FF984 UT WOS:A1991FF98400007 ER PT J AU ELKABBANI, O NARAYANA, SVL BABU, YS MOORE, KM FLYNN, TG PETRASH, JM WESTBROOK, EM DELUCAS, LJ BUGG, CE AF ELKABBANI, O NARAYANA, SVL BABU, YS MOORE, KM FLYNN, TG PETRASH, JM WESTBROOK, EM DELUCAS, LJ BUGG, CE TI PURIFICATION, CRYSTALLIZATION AND PRELIMINARY CRYSTALLOGRAPHIC ANALYSIS OF PORCINE ALDOSE REDUCTASE SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Note ID DIABETIC COMPLICATIONS; ALDEHYDE REDUCTASE; MUSCLE C1 BIOCRYST INC,BIRMINGHAM,AL 35205. QUEENS UNIV,DEPT BIOCHEM,KINGSTON K7L 3N6,ONTARIO,CANADA. WASHINGTON UNIV,SCH MED,DEPT OPHTHALMOL & VISUAL SCI,ST LOUIS,MO 63110. ARGONNE NATL LAB,BIOL ENVIRONM & MED RES,ARGONNE,IL 60439. RP ELKABBANI, O (reprint author), UNIV ALABAMA,CTR MACROMOLEC CRYSTALLOG,POB 79-THT,UAB STN,BIRMINGHAM,AL 35294, USA. FU NCRR NIH HHS [RR05807]; NEI NIH HHS [EY05856, P30-EY03039] NR 18 TC 9 Z9 9 U1 1 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD APR 20 PY 1991 VL 218 IS 4 BP 695 EP 698 DI 10.1016/0022-2836(91)90257-7 PG 4 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA FK564 UT WOS:A1991FK56400007 PM 1902521 ER PT J AU CHEN, PS AF CHEN, PS TI GRAVITATIONAL BEAMSTRAHLUNG SO MODERN PHYSICS LETTERS A LA English DT Article AB A semiclassical formalism of gravitational radiation from the collision of high energy e+e- beams is derived. The charged particles interact with the strong collective EM field of the oncoming beam and emit beamstrahlung. We show that these photons would couple to the same EM field and resonantly excite gravitational waves with much higher frequencies than those from astrophysical signals. We examine several physical examples and show that there is a finite probability for emitting such "gravitons". RP CHEN, PS (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 0 TC 10 Z9 10 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0217-7323 J9 MOD PHYS LETT A JI Mod. Phys. Lett. A PD APR 20 PY 1991 VL 6 IS 12 BP 1069 EP 1075 DI 10.1142/S0217732391001111 PG 7 WC Physics, Nuclear; Physics, Particles & Fields; Physics, Mathematical SC Physics GA FN082 UT WOS:A1991FN08200003 ER PT J AU LEE, T YEUNG, ES SHARMA, M AF LEE, T YEUNG, ES SHARMA, M TI MICELLAR ELECTROKINETIC CAPILLARY CHROMATOGRAPHIC-SEPARATION AND LASER-INDUCED FLUORESCENCE DETECTION OF 2'-DEOXYNUCLEOSIDE 5'-MONOPHOSPHATES OF NORMAL AND MODIFIED BASES SO JOURNAL OF CHROMATOGRAPHY-BIOMEDICAL APPLICATIONS LA English DT Article ID OPEN-TUBULAR CAPILLARIES; ZONE ELECTROPHORESIS; OLIGONUCLEOTIDES; DNA AB Micellar electrokinetic chromatography is used to separate dansylated nucleotides, both normal and modified species. The high separation power allows detection of minor components present in less than 1 part per thousand of the major components. Laser-excited fluorescence is used to detect the separated components at the 6 . 10(-18) mol level or 10(-9) M injected material. Combined with high-performance liquid chromatographic enrichment prior to labeling, this technique can be used to assess DNA damage in carcinogenesis studies. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. ROSWELL PK CANC INST,DEPT BIOPHYS,BUFFALO,NY 14263. FU NCI NIH HHS [CA46896] NR 26 TC 22 Z9 22 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4347 J9 J CHROMATOGR-BIOMED JI J. Chromatogr.-Biomed. Appl. PD APR 19 PY 1991 VL 565 IS 1-2 BP 197 EP 206 DI 10.1016/0378-4347(91)80383-N PG 10 WC Chemistry, Analytical SC Chemistry GA FK218 UT WOS:A1991FK21800018 PM 1874867 ER PT J AU NARAYAN, J GODBOLE, VP WHITE, CW AF NARAYAN, J GODBOLE, VP WHITE, CW TI LASER METHOD FOR SYNTHESIS AND PROCESSING OF CONTINUOUS DIAMOND FILMS ON NONDIAMOND SUBSTRATES SO SCIENCE LA English DT Article ID SEMICONDUCTORS; PHASE AB A laser method based upon carbon ion implantation and pulsed laser melting of copper has been used to produce continuous diamond thin film. Carbon ions were implanted with ion energies in the range of 60 to 120 keV, and doses of 1.0 x 10(18) to 2.0 x 10(18) ions cm-2. The ion-implanted specimens were treated with nanosecond excimer laser pulses with the following parameters: energy density, 3.0 to 5.0 J cm-2; wavelength, 0.308-mu-m; pulse width, 45 nanoseconds. The specimens were characterized with scanning electron microscopy (SEM), x-ray diffraction, Rutherford backscattering/ion channeling, Auger, and Raman spectroscopy. The macroscopic Raman spectra contained a strong peak at 1332 cm-1 with full width at half maximum of 5 cm-1, which is very close to the quality of the spectra obtained from single-crystal diamond. The selected area electron diffraction patterns and imaging confirmed the films to be defect-free single crystal over large areas of up to several square micrometers with no grain boundaries. Low voltage SEM imaging of surface features indicated the film to be continuous with presence of growth steps. C1 N CAROLINA STATE UNIV,DEPT MAT SCI & ENGN,RALEIGH,NC 27695. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. RI Narayan, Jagdish/D-1874-2009 NR 19 TC 82 Z9 83 U1 2 U2 12 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD APR 19 PY 1991 VL 252 IS 5004 BP 416 EP 418 DI 10.1126/science.252.5004.416 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FH103 UT WOS:A1991FH10300035 PM 17740941 ER PT J AU WEISS, PS MESTDAGH, JM SCHMIDT, H COVINSKY, MH LEE, YT AF WEISS, PS MESTDAGH, JM SCHMIDT, H COVINSKY, MH LEE, YT TI REACTIONS OF GROUND-STATE AND ELECTRONICALLY EXCITED SODIUM ATOMS WITH METHYL-BROMIDE AND MOLECULAR CHLORINE SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID CROSS-SECTIONS; ENERGY-DEPENDENCE; BEAM; SCATTERING; COLLISIONS; IODIDE; K+BR2; CH3I AB The reactions of ground- and excited-state Na atoms with methyl bromide (CH3Br) and chlorine (Cl2) have been studied by using the crossed molecular beams method. For both reactions, the cross sections increase with increasing electronic energy. The product recoil energies change little with increasing Na electronic energy, implying that the product internal energies increase substantially. For Na + CH3Br, the steric angle of acceptance opens with increasing electronic energy. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720. PENN STATE UNIV,DEPT CHEM,UNIVERSITY PK,PA 16802. CENS,F-91191 GIF SUR YVETTE,FRANCE. BRAUN AG FORSCH,W-6242 KRONBERG,GERMANY. RI Weiss, Paul/A-2575-2011; Lee, Yuan-Tseh/F-7914-2012 OI Weiss, Paul/0000-0001-5527-6248; NR 47 TC 13 Z9 13 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 18 PY 1991 VL 95 IS 8 BP 3005 EP 3011 DI 10.1021/j100161a013 PG 7 WC Chemistry, Physical SC Chemistry GA FH098 UT WOS:A1991FH09800013 ER PT J AU HILL, JR MOORE, DS SCHMIDT, SC STORM, CB AF HILL, JR MOORE, DS SCHMIDT, SC STORM, CB TI INFRARED, RAMAN, AND COHERENT ANTI-STOKES-RAMAN SPECTROSCOPY OF THE HYDROGEN-DEUTERIUM ISOTOPOMERS OF NITROMETHANE SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID ACI ION; HIGH-PRESSURE; DETONATION; SPECTRUM; BAND AB The vibrational spectroscopy of the four hydrogen/deuterium isotopomers of nitromethane was investigated. Infrared, Raman, and coherent anti-Stokes Raman spectroscopy (CARS) of the isotopomers were used to determine vibrational frequencies for each isotopomer. Results for the d0, d2, and d3 isotopomers agree well with literature values. Gas- and liquid-phase spectra for the d1 isotopomer are presented, and the measured vibrational frequencies compare well with a theoretical prediction. In addition, high-resolution Raman spectra of the CN stretch mode were used to analyze the elements of the anharmonic coupling matrix involving this mode. Finally, the relative differential Raman scattering cross section of the CN stretch mode of each isotopomer was determined. C1 UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RI Moore, David/C-8692-2013 NR 25 TC 39 Z9 40 U1 0 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 18 PY 1991 VL 95 IS 8 BP 3037 EP 3044 DI 10.1021/j100161a019 PG 8 WC Chemistry, Physical SC Chemistry GA FH098 UT WOS:A1991FH09800019 ER PT J AU TOTH, LM LIN, JS FELKER, LK AF TOTH, LM LIN, JS FELKER, LK TI SMALL-ANGLE X-RAY-SCATTERING FROM ZIRCONIUM(IV) HYDROUS TETRAMERS SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID IMAGE-RECONSTRUCTION AB Small-angle X-ray scattering (SAXS) data were collected for 0.035-1.0 M Zr(IV) in aqueous solution where the species present were hydroxyl-bridged tetramers. The scattering data were fitted to a cylindrical model with a radius of 4.8 angstrom and an aspect ratio of 2.3. Similar fits of the data to spherical and elliptical models were also tested. These SAXS data have provided corroborative evidence for the existence of tetrameric species in aqueous solution. RP TOTH, LM (reprint author), OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831, USA. NR 11 TC 35 Z9 36 U1 1 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 18 PY 1991 VL 95 IS 8 BP 3106 EP 3108 DI 10.1021/j100161a028 PG 3 WC Chemistry, Physical SC Chemistry GA FH098 UT WOS:A1991FH09800028 ER PT J AU BECKMAN, EJ SMITH, RD AF BECKMAN, EJ SMITH, RD TI PRESSURE EFFECTS ON THE PHASE-BEHAVIOR OF A PROPYLENE WATER SURFACTANT MIXTURE SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID REVERSE MICELLE; MICROEMULSION PHASES; LIGHT-SCATTERING; ETHANE AB The phase behavior of the propylene/water/Tergitol 7 surfactant ternary mixture has been examined as a function of pressure at 25.5-degrees-C. Unlike conventional liquid alkane based systems, a three-phase region is obtained in the absence of added electrolyte. This is likely due to a higher upper critical solution temperature for the propylene/Tergitol 7 binary mixture, in comparison to that for mixtures of various anionic surfactants and liquid alkanes. The effect of increasing pressure is similar to the effect of decreasing temperature or increasing electrolyte concentration, according to the Kahlweit phenomenological model for amphiphile/water/oil phase behavior (as well as models describing effects on interfacial curvature, such as the R ratio). The conductivities of the nominally propylene-continuous upper phases in the systems examined are high enough to suggest electrical percolation, implying the presence of significant volume fractions of micelles in these phases. C1 PACIFIC NW LAB, DEPT FOREST SCI, CHEM METHODS & SEPARAT GRP, RICHLAND, WA 99352 USA. UNIV PITTSBURGH, DEPT CHEM & PETR ENGN, PITTSBURGH, PA 15261 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 23 TC 14 Z9 14 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 18 PY 1991 VL 95 IS 8 BP 3253 EP 3257 DI 10.1021/j100161a053 PG 5 WC Chemistry, Physical SC Chemistry GA FH098 UT WOS:A1991FH09800053 ER PT J AU MURAKAMI, T INOUE, H NISHIMURA, J VANPARADIJS, J FENIMORE, EE ULMER, A YOSHIDA, A AF MURAKAMI, T INOUE, H NISHIMURA, J VANPARADIJS, J FENIMORE, EE ULMER, A YOSHIDA, A TI A GAMMA-RAY BURST PRECEDED BY X-RAY ACTIVITY SO NATURE LA English DT Article ID NEUTRON STARS; GINGA; ABSORPTION; SCATTERING; CYCLOTRON; FEATURES AB GAMMA-RAY bursts remain mysterious astrophysical phenomena. The discovery of cyclotron harmonics 1-3 in their spectra is strong evidence that they originate from strongly magnetized neutron stars, but their energy source and photon production mechanism are unknown. In observations of a gamma-ray burst using the Ginga astronomy satellite, we detected X-ray emission in the 2-10 keV energy range approximately 10 s before the onset of the gamma-ray event, as well as a tail of X-ray emission for approximately 30 s afterwards. The long timescale and near black-body spectrum of the precursory X-ray emission suggests that the burst mechanism involves a transition from thermal to non-thermal photon production, and that the energy source for the burst comes from within the neutron star rather than from accretion. C1 CTR HIGH ENERGY ASTROPHYS,1098 SJ AMSTERDAM,NETHERLANDS. INST CHEM & PHYS RES,SAITAMA 351,JAPAN. UNIV AMSTERDAM,ASTRON INST ANTON PANNEKOEK,AMSTERDAM,NETHERLANDS. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RP MURAKAMI, T (reprint author), INST SPACE & ASTRONAUT SCI,1-1 YOSHINODAI 3-CHOME,SAGAMIHARA,KANAGAWA 229,JAPAN. NR 24 TC 87 Z9 87 U1 0 U2 0 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD APR 18 PY 1991 VL 350 IS 6319 BP 592 EP 594 DI 10.1038/350592a0 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FH112 UT WOS:A1991FH11200052 ER PT J AU COOPER, F MOSHE, M AF COOPER, F MOSHE, M TI SCALING RELATIONS AND THE DELTA EXPANSION SO PHYSICS LETTERS B LA English DT Article ID QUANTUM-FIELD THEORY; PERTURBATIVE SCHEME AB The delta-expansion is an expansion of a quantum field theory in a parameter describing the degree of non-linearity of the theory. We show how to use engineering scaling relations to enforce the correct functional dependence of physical quantities on the coupling constant g when calculated order by order in delta and thus improving the accuracy of the delta-expansion. To illustrate this idea we study the equal-time correlation functions for supersymmetric quantum mechanics, and the effective potential for a generalized Gross-Neveu model: g2(PSI-PSI)2-delta in the large-N limit. C1 TECHNION ISRAEL INST TECHNOL,DEPT PHYS,IL-32000 HAIFA,ISRAEL. RP COOPER, F (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 6 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 18 PY 1991 VL 259 IS 1-2 BP 101 EP 105 DI 10.1016/0370-2693(91)90141-C PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FJ340 UT WOS:A1991FJ34000019 ER PT J AU FRANKENBACH, GM BENO, MA WILLIAMS, JM AF FRANKENBACH, GM BENO, MA WILLIAMS, JM TI CHARGE-TRANSFER COMPLEX OF 2,2',5,5'-TETRATHIAFULVALENE AND PARA-BENZOQUINONE SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID SALTS AB The charge-transfer complex of 2,2',5,5'-tetrathiafulvalene (TTF) and p-benzoquinone, C6H4S4.C6H4O2, M(r) = 312.44, monoclinic, P2(1)/n, a = 6.385 (6), b = 15.49 (1), c = 6.935 (7) angstrom, beta = 104.76 (7)degrees, V = 663 (1) angstrom 3, Z = 2, D(x) = 1.565 (3) g cm-3, lambda(Mo K-alpha) = 0.71073 angstrom, mu = 6.8 cm-1, F(000) = 320, T = 300 K, R = 0.029, wR = 0.036 for 1292 unique reflections with \F(o)\ > 3-sigma(F(o)). TTF and benzoquinone unexpectedly form a mixed-stack complex despite incompatible orbital overlap. C1 ARGONNE NATL LAB,DIV CHEM & MAT SCI,9700 CASS AVE,ARGONNE,IL 60439. NR 8 TC 5 Z9 5 U1 0 U2 1 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 APR 15 PY 1991 VL 47 BP 762 EP 764 DI 10.1107/S0108270190007958 PN 4 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA FJ773 UT WOS:A1991FJ77300027 ER PT J AU DOSE, EV JACOBSON, S GUIOCHON, G AF DOSE, EV JACOBSON, S GUIOCHON, G TI DETERMINATION OF ISOTHERMS FROM CHROMATOGRAPHIC PEAK SHAPES SO ANALYTICAL CHEMISTRY LA English DT Article ID NONLINEAR GAS-CHROMATOGRAPHY; SOLID EQUILIBRIUM ISOTHERMS; GRAPHITIZED CARBON-BLACK; ADSORPTION-ISOTHERMS; LIQUID-CHROMATOGRAPHY; PULSE METHOD; SURFACE COVERAGE; SILICA; MODEL; ZERO AB A new method for determining equilibrium isotherms from chromatographic peak shapes is presented. It differs from alternative methods like elution by characteristic point in that the present method accounts for the finite efficiency of real chromatographic columns, and so the new method is used to its best advantage in systems of low plate number. In the new method, initial estimates of the parameters of an isotherm equation are refined by finding simulated chromatographic peak shapes that most nearly approximate the experimental peak shapes. A series of example determinations demonstrate the method's utility. C1 UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37831. NR 49 TC 73 Z9 76 U1 3 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD APR 15 PY 1991 VL 63 IS 8 BP 833 EP 839 DI 10.1021/ac00008a020 PG 7 WC Chemistry, Analytical SC Chemistry GA FF992 UT WOS:A1991FF99200021 ER PT J AU HUANG, JY SHEN, YR CHEN, CT WU, BC AF HUANG, JY SHEN, YR CHEN, CT WU, BC TI NONCRITICALLY PHASE-MATCHED 2ND-HARMONIC GENERATION AND OPTICAL PARAMETRIC AMPLIFICATION IN A LITHIUM TRIBORATE CRYSTAL SO APPLIED PHYSICS LETTERS LA English DT Article ID LIB3O5; NM AB We evaluate the potential of lithium triborate (LBO) temperature-tuned to achieve type-I noncritical phase matching, for picosecond high-power second-harmonic generation (SHG) and tunable optical parametric amplification (OPA). Pumped by 35 ps, 1.064-mu-m laser pulses, a conversion efficiency of 65% was obtained from SHG. The output of OPA, pumped by 0.532-mu-m was tunable from 0.75 to 1.8-mu-m with an efficiency better than 20%. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MED,BERKELEY,CA 94720. CHINESE ACAD SCI,FUJIAN INST RES STRUCT MATTER,FUZHOU,PEOPLES R CHINA. RP HUANG, JY (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. NR 11 TC 27 Z9 29 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 15 PY 1991 VL 58 IS 15 BP 1579 EP 1581 DI 10.1063/1.105156 PG 3 WC Physics, Applied SC Physics GA FG034 UT WOS:A1991FG03400001 ER PT J AU FRITZ, IJ MYERS, DR VAWTER, GA BRENNAN, TM HAMMONS, BE AF FRITZ, IJ MYERS, DR VAWTER, GA BRENNAN, TM HAMMONS, BE TI NOVEL REFLECTANCE MODULATOR EMPLOYING AN INGAAS/ALGAAS STRAINED-LAYER SUPERLATTICE FABRY-PEROT CAVITY WITH UNSTRAINED INGAAS/INALAS MIRRORS SO APPLIED PHYSICS LETTERS LA English DT Article ID OPTICAL INTERFERENCE FILTERS; SINGLE-CRYSTAL; EPITAXIAL MULTILAYERS; REFRACTIVE-INDEX; HIGH-EFFICIENCY; QUANTUM WELLS; WAVE AB We present a novel approach to optoelectronic devices by combining mechanically stable strained and unstrained epitaxial multilayers. We illustrate our approach with an optical reflectance modulator based on an asymmetric Fabry-Perot resonator designed to operate near 1.06-mu-m. The resonator is grown on a mechanically relaxed buffer of In0.11Ga0.89As deposited on a GaAs substrate. For mirrors, quarter-wave stacks of In0.11Ga0.89As and In0.1Al0.9As, lattice matched to the buffer, are used. The Fabry-Perot cavity consists of an In0.23Ga0.77As/Al0.35Ga0.65As strained-layer superlattice whose planar lattice constant also matches the buffer. Our first device operates at 1.04-1.05-mu-m depending on lateral position across the wafer. The insertion loss at resonance is less than 2 db and a fractional modulation of over 60% has been achieved with a 4 V bias swing. RP FRITZ, IJ (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 20 TC 29 Z9 29 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 15 PY 1991 VL 58 IS 15 BP 1608 EP 1610 DI 10.1063/1.105140 PG 3 WC Physics, Applied SC Physics GA FG034 UT WOS:A1991FG03400011 ER PT J AU WALUKIEWICZ, W HALLER, EE AF WALUKIEWICZ, W HALLER, EE TI EFFECT OF SCATTERING BY NATIVE DEFECTS ON ELECTRON-MOBILITY IN MODULATION-DOPED HETEROSTRUCTURES SO APPLIED PHYSICS LETTERS LA English DT Article ID GAAS-ALGAAS HETEROJUNCTIONS; CM2/V S; TEMPERATURE; GAS; EPITAXY AB The effect of scattering by native defects on carrier mobility in modulation-doped heterostructures is calculated. The concentration of the defects is determined using the amphoteric native defect model. It is shown that the Fermi level induced reduction of the defect formation energy leads to an increased incorporation of native defects and reduced mobility in AlGaAs/GaAs inverted modulation-doped heterostructures. This new mechanism explains the experimentally observed difference in the values of electron mobilities in normal and inverted modulation-doped heterostructures. The effects of native defects on the carrier mobilities in heterostructures based on other semiconductor systems are also discussed. RP WALUKIEWICZ, W (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT SCI,CTR ADV MAT,BERKELEY,CA 94720, USA. NR 18 TC 3 Z9 3 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 15 PY 1991 VL 58 IS 15 BP 1638 EP 1640 DI 10.1063/1.105150 PG 3 WC Physics, Applied SC Physics GA FG034 UT WOS:A1991FG03400021 ER PT J AU GATLEY, SJ AF GATLEY, SJ TI ACTIVITIES OF THE ENANTIOMERS OF COCAINE AND SOME RELATED-COMPOUNDS AS SUBSTRATES AND INHIBITORS OF PLASMA BUTYRYLCHOLINESTERASE SO BIOCHEMICAL PHARMACOLOGY LA English DT Article ID HUMAN-SERUM CHOLINESTERASE; CAUDATE-NUCLEUS; HORSE SERUM; ACETYLCHOLINESTERASE; HYDROLYSIS; PSEUDOCHOLINESTERASE; RECEPTORS; BINDING; SITES; BRAIN AB The behaviors of the enantiomers of cocaine (benzoylecgonine methyl ester) and related compounds with butyrylcholinesterase (BChE; EC 3.1.1.8) were investigated spectrophotometrically at 235 nm. The unnatural enantiomer, (+)-cocaine, was hydrolyzed by BChE (extinction coefficient 6.7 L.mmol-1.cm-1) at about half the rate of benzoylcholine, but over 2000 times faster than naturally occurring (-)-cocaine. This rapid hydrolysis of (+)-cocaine may account, in part, for its pharmacological inactivity. (+)-Norcocaine, (+)-benzoylecgonine, (-)-psi-cocaine and tropacocaine were also substrates for BChE. Hydrolysis of (+)-cocaine was sensitive to several standard inhibitors of BChE, including those of competitive, carbamate and organophosphorus classes. Although (-)-cocaine was a poor substrate for debenzoylation, it was a fairly good competitive inhibitor (K(i) approximately 10-mu-M) of the hydrolysis of other substrates. The cocaine metabolites (-)-norcocaine, (-)-benzoylecgonine and (-)-ecgonine methyl ester inhibited BChE with K(i) values of 15, 76 and 1300-mu-M, respectively. (+)-psi-Cocaine had K(i) = 3-mu-M. p-Nitro and p-fluoro derivatives of cocaine and analogs with phenyl and p-fluorophenyl groups in place of the benzoyl ester linkage (WIN 35,065-2 and WIN 35,428) inhibited BChE comparably to (-)-cocaine itself. Both cocaine enantiomers were weak inhibitors of acetylcholinesterase (AChE; EC 3.1.1.7) from human erythrocytes with similar K(i) values (160-170-mu-M). Although it is unlikely that the inhibition of BChE is an important factor in the subjective effects of cocaine, it may have implications for the toxicity of cocaine to the fetus, since BChE appears in the development of the central nervous system before AChE, and has been suggested to function as an embryonic acetylcholinesterase. RP GATLEY, SJ (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. FU NIDA NIH HHS [DA06278] NR 54 TC 69 Z9 69 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0006-2952 J9 BIOCHEM PHARMACOL JI Biochem. Pharmacol. PD APR 15 PY 1991 VL 41 IS 8 BP 1249 EP 1254 DI 10.1016/0006-2952(91)90665-R PG 6 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA FE406 UT WOS:A1991FE40600020 PM 2009099 ER PT J AU STOFFEL, JJ LAUE, HJ AF STOFFEL, JJ LAUE, HJ TI MULTIPLE-SECTOR ISOTOPE-RATIO MASS-SPECTROMETER DESIGN FOR HIGH TRANSMISSION EFFICIENCY SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY AND ION PROCESSES LA English DT Article AB The design of multiple-sector isotope-ratio mass spectrometers has been investigated for the purpose of improving ion transmission efficiency while maintaining high abundance sensitivity. Various magnet geometries with normal and non-normal field boundaries were examined. The most favorable geometry found for tandem 90-degrees-deflection magnets has boundaries 17-degrees-off-normal and drift lengths 1.44 times the radius of deflection. The ion beam is rendered parallel in the vertical plane at the focus of the first magnet and is brought to a stigmatic focus by the second magnet. This geometry provides a 16% increase in mass resolution over normal geometry and gives 100% transmission without the need for intermediate focusing lenses. Complete transmission is also maintained with the addition of a cylindrical electric sector as a third stage for greater abundance sensitivity. C1 PURDUE UNIV, W LAFAYETTE, IN 47907 USA. RP STOFFEL, JJ (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 10 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1176 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. Ion Process. PD APR 15 PY 1991 VL 105 IS 3 BP 225 EP 238 DI 10.1016/0168-1176(91)87014-R PG 14 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA FJ861 UT WOS:A1991FJ86100004 ER PT J AU BAO, XJ SCHLESINGER, TE JAMES, RB GENTRY, GL CHENG, AY ORTALE, C AF BAO, XJ SCHLESINGER, TE JAMES, RB GENTRY, GL CHENG, AY ORTALE, C TI STUDY OF SEMITRANSPARENT PALLADIUM CONTACTS ON MERCURIC IODIDE BY PHOTOLUMINESCENCE SPECTROSCOPY AND THERMALLY STIMULATED CURRENT MEASUREMENTS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID NUCLEAR RADIATION DETECTORS; HGI2; RESOLUTION; CRYSTALS; LUMINESCENCE; SPECTRUM; DEFECTS; GROWTH AB Semitransparent palladium contacts on mercuric iodide were studied by low temperature photoluminescence spectroscopy and thermally stimulated conductivity. These contacts were deposited either by thermal evaporation or by plasma sputtering. Changes due to palladium deposition were found in the photoluminescence spectra and were attributed to modifications in the stoichiometry within the palladium/mercuric iodide interfacial region. Thermally stimulated conductivity measurements revealed two dominant traps with activation energies of 0.010 and 0.54 eV. The importance of these traps in the application of nuclear detection is discussed. C1 SANDIA NATL LABS,DIV ADV MAT RES,LIVERMORE,CA 94550. EG&G ENERGY MEASUREMENTS INC,GOLETA,CA 93116. RP BAO, XJ (reprint author), CARNEGIE MELLON UNIV,DEPT ELECT & COMP ENGN,PITTSBURGH,PA 15213, USA. NR 35 TC 9 Z9 9 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4247 EP 4252 DI 10.1063/1.348396 PN 1 PG 6 WC Physics, Applied SC Physics GA FL728 UT WOS:A1991FL72800013 ER PT J AU XU, Y LAABS, FC BEAUDRY, BJ GSCHNEIDNER, KA AF XU, Y LAABS, FC BEAUDRY, BJ GSCHNEIDNER, KA TI PRESSURE-ASSISTED REACTION BONDING BETWEEN W AND SI80GE20 ALLOY WITH NI AS THE INTERLAYER SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB The conditions and reaction mechanism of W/Ni/Si80Ge20 hot-press bonding have been studied. It was found that a Ni/Si80Ge20 bond can be formed using low pressure, 19.6 MPa, in the temperature range between 780 and 900-degrees-C in a short time. The kinetics follows a parabolic pattern, suggesting it is a diffusion-controlled process. The activation energy is 2.7 eV and the parabolic rate constant is given by K(P) = 4.0 X 10(14) exp(-3.2 X 10(4)/T) (mu-m2/min). The bonding interface has a multilayered structure. A phenomenological mechanism of the bonding formation has been proposed based on scanning electron microscopy observations and energy dispersive spectroscopy. The cracking problem due to thermal stress is discussed based on Oxx's equation. It was found that bonds free from cracks in the Si80Ge20 alloy are formed when the Ni consumption (as measured by the thickness of the nickel layer) is sufficiently small (< 40-45-mu-m) and the post-hot-press cooling is slow. On the other hand, tungsten and nickel react during hot pressing at higher temperature, forming WNi4. As an interlayer, nickel can join the tungsten sheet and the Si80Ge20 together. It has been also demonstrated that a thin nickel layer formed by vapor deposition on a tungsten sheet may be used as the interlayer in place of nickel sheet. C1 UNIV SCI & TECHNOL CHINA,DEPT CORROS,BEIJING 100083,PEOPLES R CHINA. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT MAT SCI & ENGN,AMES,IA 50011. NR 16 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4292 EP 4299 DI 10.1063/1.348402 PN 1 PG 8 WC Physics, Applied SC Physics GA FL728 UT WOS:A1991FL72800019 ER PT J AU WARREN, WL LENAHAN, PM BRINKER, CJ ASHLEY, CS REED, ST SHAFFER, GR AF WARREN, WL LENAHAN, PM BRINKER, CJ ASHLEY, CS REED, ST SHAFFER, GR TI SOL-GEL SILICATE THIN-FILM ELECTRONIC-PROPERTIES SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TRANSITION; DIOXIDE AB We have explored the effects of various processing parameters on the dielectric and electronic integrity of sol-gel-derived silicate thin films and have identified several factors that strongly affect the thin-film electronic properties. We find that sol-gel dielectrics can exhibit excellent dielectric integrity: viz., low interface trap densities and fairly good insulating properties approaching those of a thermally grown silicon dioxide film on silicon. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. PENN STATE UNIV,UNIVERSITY PK,PA 16802. NR 18 TC 21 Z9 21 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4404 EP 4408 DI 10.1063/1.348366 PN 1 PG 5 WC Physics, Applied SC Physics GA FL728 UT WOS:A1991FL72800036 ER PT J AU MERZBACHER, CI BONNER, BP AF MERZBACHER, CI BONNER, BP TI DETERMINATION OF OXYGEN-CONTENT AND CARBONATE IMPURITY IN YBA2CU3O7-X BY DIFFUSE REFLECTANCE INFRARED-SPECTROSCOPY SO JOURNAL OF APPLIED PHYSICS LA English DT Note ID SUPERCONDUCTORS; PHONONS; WATER AB Samples of YBa2Cu3O7-x with x ranging from approximately 0 to 0.65 have been analyzed by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) in the midinfrared region (400-6000 cm-1). Spectral line shapes vary gradually as a function of oxygen stoichiometry, and the reflectance at 400 and 1000 cm-1 decreases linearly with decreasing oxygen content. Spectra of samples that were incompletely synthesized or exposed to a 4% CO2 atmosphere at 650-degrees-C clearly indicated the presence of carbonate. DRIFTS is therefore a quick, nondestructive method for determining oxygen content in YBa2Cu3O7-x powders, and for detecting carbonate species due to synthesis error or reaction with CO2-bearing atmosphere. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DEPT EARTH SCI,LIVERMORE,CA 94550. NR 10 TC 5 Z9 5 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4442 EP 4444 DI 10.1063/1.348374 PN 1 PG 3 WC Physics, Applied SC Physics GA FL728 UT WOS:A1991FL72800044 ER PT J AU HAYDEN, SM AEPPLI, G CHEONG, SW MOOK, HA FISK, Z RYTZ, D AF HAYDEN, SM AEPPLI, G CHEONG, SW MOOK, HA FISK, Z RYTZ, D TI NEUTRON-SCATTERING STUDIES ON LANTHANUM CUPRATES (INVITED) SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. HUGHES RES LAB,MALIBU,CA 90265. RP HAYDEN, SM (reprint author), INST MAX VON LAUE PAUL LANGEVIN,F-38042 GRENOBLE,FRANCE. RI Hayden, Stephen/F-4162-2011 OI Hayden, Stephen/0000-0002-3209-027X NR 0 TC 0 Z9 0 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4519 EP 4519 DI 10.1063/1.348344 PN 2A PG 1 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200019 ER PT J AU TRUGMAN, SA AF TRUGMAN, SA TI HOLE DYNAMICS IN THE COPPER-OXIDE PLANES SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract RP TRUGMAN, SA (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,B262,LOS ALAMOS,NM 87545, USA. NR 1 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4519 EP 4519 DI 10.1063/1.348345 PN 2A PG 1 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200020 ER PT J AU CAREY, MJ SPADA, FE PARKER, FT BERKOWITZ, AE LEROUX, C AF CAREY, MJ SPADA, FE PARKER, FT BERKOWITZ, AE LEROUX, C TI EXCHANGE-ANISOTROPY IN NI80FE20/COXNI1-XO COUPLED FILMS SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 UNIV CALIF SAN DIEGO,CTR MAGNET RECORDING RES,LA JOLLA,CA 92093. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,NATL CTR ELECTRON MICROSCOPY,BERKELEY,CA 94720. RP CAREY, MJ (reprint author), UNIV CALIF SAN DIEGO,DEPT PHYS,R-001,LA JOLLA,CA 92093, USA. RI christine, leroux/H-4635-2013 OI christine, leroux/0000-0003-4649-9305 NR 0 TC 0 Z9 0 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4547 EP 4547 DI 10.1063/1.348355 PN 2A PG 1 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200030 ER PT J AU MOOG, ER ZAK, J BADER, SD AF MOOG, ER ZAK, J BADER, SD TI ANALYSIS OF KERR ROTATION FROM CU/CO, PD/CO, AND PT/CO SUPERLATTICES SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID CO/PT-LAYERED STRUCTURES; PERPENDICULAR MAGNETIC-ANISOTROPY; MULTILAYERED FILMS; RECORDING MATERIALS; ULTRATHIN CO/PT AB Numerical simulations of the Kerr signals from Cu/Co, Pd/Co, and Pt/Co superlattices show, in general, a scaling of the signal with the amount of Co in the superlattice. Experimentally, however, the signal from Pt/Co superlattices at approximately 4 eV is larger than that from bulk Co, despite the lesser total amount of Co. This is due to the magnetization induced in the Pt by the Co. Comparison of the Pd/Co and Pt/Co results with experiment indicates that the magnetization induced in the Pt by the Co plays a more important role in the magneto-optic activity than does the induced magnetization of Pd. C1 TECHNION ISRAEL INST TECHNOL,HAIFA,ISRAEL. RP MOOG, ER (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. RI Bader, Samuel/A-2995-2013 NR 28 TC 23 Z9 23 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4559 EP 4561 DI 10.1063/1.348309 PN 2A PG 3 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200036 ER PT J AU FULLERTON, EE SCHULLER, IK PARKER, FT GRIMSDITCH, M SOWERS, CH ROBERTSON, W KUMAR, S BELIEN, P BRUYNSERAEDE, Y AF FULLERTON, EE SCHULLER, IK PARKER, FT GRIMSDITCH, M SOWERS, CH ROBERTSON, W KUMAR, S BELIEN, P BRUYNSERAEDE, Y TI MAGNETIC-PROPERTIES OF FE/CR AND FE/CU SUPERLATTICES SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 UNIV CALIF SAN DIEGO,CMRR R-001,LA JOLLA,CA 92093. ARGONNE NATL LAB,ARGONNE,IL 60439. CATHOLIC UNIV LEUVEN,VASTE STOF FYS & MAGNETISME LAB,B-3030 HEVERLEE,BELGIUM. RP FULLERTON, EE (reprint author), UNIV CALIF SAN DIEGO,DEPT PHYS,B-019,LA JOLLA,CA 92093, USA. RI Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 0 TC 0 Z9 0 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4801 EP 4801 DI 10.1063/1.348234 PN 2A PG 1 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200122 ER PT J AU REBELSKY, L LIN, H COLLINS, MF GARRETT, JB BUYERS, WJL MCELFRESH, MW TORIKACHVILI, MS AF REBELSKY, L LIN, H COLLINS, MF GARRETT, JB BUYERS, WJL MCELFRESH, MW TORIKACHVILI, MS TI MAGNETIC PHASE-TRANSITIONS IN UNI2SI2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID NEUTRON-DIFFRACTION; URU2SI2 AB We report neutron diffraction measurements on a single crystal of UNi2 Si2. Three magnetically ordering phases are observed below 123 K with the magnetic moment parallel to the c-axis in all three phases. The low temperature (T < 53 K) phase is a superposition of a commensurate spin density wave with wave vector q = (0 0 0.667 +/- 0.002) and a ferromagnetic ordered moment of 1.1 +/- 0.3-mu-B, the intermediate (53 K < T < 103 K) is a simple body-centered tetragonal antiferromagnet with an ordered magnetic moment of 1.8 +/- 0.2-mu-B and the high-temperature phase is an incommensurate spin density wave with wave vector q = (0 0 0.744 +/- 0.002) at 110 K. The phase transitions at 53 and 103 K are first order. C1 MCMASTER UNIV,INST MAT RES,HAMILTON L8S 4M1,ONTARIO,CANADA. ATOM ENERGY CANADA LTD,CHALK RIVER K0J 1J0,ONTARIO,CANADA. IBM CORP,YORKTOWN HTS,NY 10598. SAN DIEGO STATE UNIV,SAN DIEGO,CA 92182. RP REBELSKY, L (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 14 TC 10 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4807 EP 4809 DI 10.1063/1.348237 PN 2A PG 3 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200125 ER PT J AU REBELSKY, L MCELFRESH, MW TORIKACHVILI, MS POWELL, BM MAPLE, MB AF REBELSKY, L MCELFRESH, MW TORIKACHVILI, MS POWELL, BM MAPLE, MB TI MAGNETIC AND STRUCTURAL PHASE-TRANSITIONS IN UAU2SI2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC AB We report magnetic susceptibility, neutron, and x-ray diffraction measurements on polycrystalline UAu2Si2. Magnetic susceptibility data show the existence of two phases below 50 K. Since no superlattice neutron peaks were observed within the sensitivity of the apparatus we conclude that the system is not a canted ferromagnet, as was suggested earlier. On the basis of the temperature dependence of the neutron and x-ray intensity we discuss a possibility that UAu2Si2 undergoes two structural phase transitions, at 48 and at 18 K and that these transitions are correlated with the magnetic state of the material. C1 IBM CORP,YORKTOWN HTS,NY 10598. ATOM ENERGY CANADA LTD,CHALK RIVER K0J 1J0,ONTARIO,CANADA. SAN DIEGO STATE UNIV,DEPT PHYS,SAN DIEGO,CA 92182. RP REBELSKY, L (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 8 TC 7 Z9 7 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4810 EP 4812 DI 10.1063/1.348238 PN 2A PG 3 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200126 ER PT J AU WANG, XL STASSIS, C JOHNSTON, DC LEUNG, TC YE, J HARMON, BN LANDER, GH SCHULTZ, AJ LOONG, CK HONIG, JM AF WANG, XL STASSIS, C JOHNSTON, DC LEUNG, TC YE, J HARMON, BN LANDER, GH SCHULTZ, AJ LOONG, CK HONIG, JM TI THE ANTIFERROMAGNETIC FORM-FACTOR OF LA2NIO4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID SUPERCONDUCTIVITY AB Neutron-diffraction techniques have been used to study the antiferromagnetic form factor of a La2NiO4 single crystal at 15 K. The antiferromagnetic form factor was obtained by measuring the integrated intensities of 16 magnetic reflections. A plateau is clearly seen at low Q (up to 3 angstrom-1) in the experimentally determined form factor, similar to those observed for La2CuO4 and Sr2CuO2Cl2. As in the case of these latter compounds, the fit of the experimental data by a Ni2+ ionic form factor is not satisfactory. The experimental data are compared with a recent spin-polarized band calculation and with a covalency model. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. COMMISS EUROPEAN COMMUNITIES,KARLSRUHE,GERMANY. ARGONNE NATL LAB,ARGONNE,IL 60439. PURDUE UNIV,DEPT CHEM,W LAFAYETTE,IN 47907. RP WANG, XL (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. RI Wang, Xun-Li/C-9636-2010 OI Wang, Xun-Li/0000-0003-4060-8777 NR 12 TC 9 Z9 9 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4860 EP 4862 DI 10.1063/1.348204 PN 2A PG 3 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200146 ER PT J AU COFFEY, D AF COFFEY, D TI CALCULATION OF THE STATIC MAGNETIZATION OF METAMAGNETIC LA2CUO4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID ANTIFERROMAGNETIC-RESONANCE; SPIN AB Interactions in La2CuO4 are predominantly antiferromagnetic. However, a strong field-induced transition is seen in the static magnetic susceptibility which points to the existence of a net ferromagnetic moment in the CuO layers. Here, this net ferromagnetic moment is incorporated into a description of the CuO layers by the inclusion of a modified Dzyaloshinskii-Moriya term in the Hamiltonian. The spin-wave spectrum in the presence of an applied field is calculated with this Hamiltonian and the ground state is determined as a function of applied field from the free energy. A calculation of the static magnetization as a function of applied field perpendicular to the CuO layers is used to determine the parameters of the model. Comparison is made with experiment. RP COFFEY, D (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,CTR MAT RES,LOS ALAMOS,NM 87545, USA. NR 13 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4863 EP 4865 DI 10.1063/1.348205 PN 2A PG 3 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200147 ER PT J AU LANDER, GH BROWN, PJ STASSIS, C GOPALAN, P SPALEK, J HONIG, G AF LANDER, GH BROWN, PJ STASSIS, C GOPALAN, P SPALEK, J HONIG, G TI NEUTRON AND MAGNETIZATION STUDY OF LA1.8SR0.2NIO4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID LA2NIO4 AB Magnetization and neutron-diffraction experiments with both polarized and unpolarized neutrons have been performed on single crystals of La1.8Sr0.2NiO4. The susceptibility is highly anisotropic at low temperature, chi-ab (field applied perpendicular to long axis) showing a peak at approximately 18 K. However, no evidence has been found for long-range magnetic order. It is speculated that the low-temperature state is a spin glass, with 18 K being the freezing temperature. Polarized neutron diffraction has been used to measure the induced magnetization density in a field of 4.6 T and at 20 K. The results can be understood by using an expanded Ni2+ from factor and invoking a small positive susceptibility at the La site. There is also evidence for covalency between the Ni and O(2) atoms along the c axis. The material distorts from tetragonal (I4/mmm) to orthorhombic (Bmab) at 120 +/- 5 K. The structural parameters are similar to those of La2NiO4. C1 INST MAX VON LAUE PAUL LANGEVIN, F-38042 GRENOBLE, FRANCE. IOWA STATE UNIV SCI & TECHNOL, DEPT PHYS, AMES, IA 50011 USA. IOWA STATE UNIV SCI & TECHNOL, AMES LAB, AMES, IA 50011 USA. PURDUE UNIV, DEPT PHYS & CHEM, W LAFAYETTE, IN 47907 USA. RP LANDER, GH (reprint author), COMMISS EUROPEAN COMMUNITIES, JOINT RES CTR, POSTFACH 2340, W-7500 KARLSRUHE, GERMANY. NR 9 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4869 EP 4871 DI 10.1063/1.348207 PN 2A PG 3 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200149 ER PT J AU VIER, DC SCHULTZ, S RETTORI, C RAO, D OSEROFF, SB TOVAR, M FISK, Z CHEONG, SW AF VIER, DC SCHULTZ, S RETTORI, C RAO, D OSEROFF, SB TOVAR, M FISK, Z CHEONG, SW TI OBSERVATION OF AN UNUSUAL ESR SIGNAL IN ANTIFERROMAGNETIC EU2CUO4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC AB We report the observation of an unusual electron spin resonance (ESR) signal in single crystals of Eu2CuO4. The signal appears to be associated with a resonance mode of the CuO2 planes, similar to the midfield and low-field absorptions we have reported previously [Phys. Rev. B 41, 1934 (1990)]. However, it is only observed when the projection of the applied de magnetic field in the CuO2 plane is within a few degrees of the <110> crystallographic direction. Additionally the sample must be field cooled in the CuO2 plane, but with a component of the cooling field perpendicular to the <110> ESR observation direction. Both the field for resonance and the linewidth exhibit a 1/cos theta-dependence, where theta is the angle of the applied dc field between the c axis and the <110> observation direction. Additional constraints for observation of the resonance are that the microwave rf magnetic field must have a component in the CuO2 plane, but perpendicular to the dc field. The signal disappears above approximately 215 K, which we assume is associated with the antiferromagnetic ordering temperature. C1 SAN DIEGO STATE UNIV,DEPT PHYS,SAN DIEGO,CA 92182. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RP VIER, DC (reprint author), UNIV CALIF SAN DIEGO,DEPT PHYS 0319,LA JOLLA,CA 92093, USA. RI Rettori, Carlos/C-3966-2012 OI Rettori, Carlos/0000-0001-6692-7915 NR 1 TC 6 Z9 6 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4872 EP 4873 DI 10.1063/1.348208 PN 2A PG 2 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200150 ER PT J AU SMITH, MG TAYLOR, RD OESTERREICHER, H AF SMITH, MG TAYLOR, RD OESTERREICHER, H TI FE-SITE OCCUPANCY AND SUPERCONDUCTIVITY IN Y1-ZCAZBA2(CU1-XFEX)3O6+Y SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID THERMAL TREATMENTS AB X-ray diffraction and Fe-57 Mossbauer spectroscopy studies show that partial substitution of Ca for Y in Y(1-z)Ca(z)Ba2(Cu(1-x)Fe(x))3O6+y (0.05 less-than-or-equal-to z less-than-or-equal-to 0.15, 0.003 less-than-or-equal-to x less-than-or-equal-to 0.20) result in increased Fe solubility and a larger percentage of Fe occupancy of the Cu(2) plane site (prepared conventionally). Materials with z > 0.00 have a slightly depressed superconducting transition onset temperature T(c) relative to the z = 0.00 compounds. It is also shown that Fe occupancy of the Cu(2) site in Y(1-z)Ca(z)Ba2(Cu(1-x)Fe(x)) 3O6+y can be substantially increased when these materials are treated at high temperatures in inert atmospheres followed by oxygenation at low temperatures. T(c) decreases more rapidly in these latter materials compared to the conventionally prepared ones. Implications concerning ordered Fe-cluster formation and superconducting pair breaking in the Cu(2) site are drawn. C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV PHYS,LOS ALAMOS,NM 87545. UNIV CALIF SAN DIEGO,DEPT CHEM,LA JOLLA,CA 92093. NR 8 TC 33 Z9 33 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4894 EP 4896 DI 10.1063/1.348216 PN 2A PG 3 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200158 ER PT J AU HODGDON, ML AF HODGDON, ML TI COMPUTATION OF SUPERCONDUCTOR CRITICAL CURRENT DENSITIES AND MAGNETIZATION CURVES SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC AB Using a constitutive law for superconductor hysteresis and the ideals of the critical state model, a system of equations is developed for the critical current density J(c), the equilibrium magnetization M(e), the upper and lower portions M(u) and M(L) of the major hysteresis loop, and their derivatives with respect to the applied field. The constitutive law consists of the differential equation dB/dH = alpha (H)s(H)[f(H) - B] + g(H) for H not-equal 0, and a rule governing the abrupt changes observed at the turning points of H. For the case presented here in which f, g, and alpha have analytic forms, the constitutive law yields an easily differentiable expression for the major loop. Hysteresis curves computed from this constitutive law are shown to be in good agreement with experiments. Exponential approximations are given for the critical current densities computed by this method for a polycrystalline sample of YBa2Cu3O(x) between 5 and 40 K. RP HODGDON, ML (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 4904 EP 4906 DI 10.1063/1.348222 PN 2A PG 3 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200165 ER PT J AU LAWSON, AC GOLDSTONE, JA HUBER, JG GIORGI, AL CONANT, JW SEVERING, A CORT, B ROBINSON, RA AF LAWSON, AC GOLDSTONE, JA HUBER, JG GIORGI, AL CONANT, JW SEVERING, A CORT, B ROBINSON, RA TI MAGNETIC-STRUCTURES OF ACTINIDE MATERIALS BY PULSED NEUTRON-DIFFRACTION SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC AB We describe some attempts to observe magnetic structure in various actinide (5f-electron) materials. Our experimental technique is neutron powder diffraction as practiced at a spallation (pulsed) neutron source. We will discuss our investigations of alpha-Pu, delta-Pu, alpha-UD3, and beta-UD3. beta-UD3 is a simple ferromagnet: Surprisingly, the moments on the two nonequivalent uranium atoms are the same within experimental error. alpha-UD3, alpha-Pu, and delta-Pu are nonmagnetic, within the limits of our observations. Our work with pulsed neutron diffraction shows that it is a useful technique for research on magnetic materials. RP LAWSON, AC (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 21 TC 15 Z9 15 U1 2 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5112 EP 5116 DI 10.1063/1.348140 PN 2A PG 5 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200242 ER PT J AU YANG, DP HINES, WA CLARK, WG MACHADO, FLA AZEVEDO, LA GIESSEN, BC QUAN, MX AF YANG, DP HINES, WA CLARK, WG MACHADO, FLA AZEVEDO, LA GIESSEN, BC QUAN, MX TI MAGNETIZATION STUDY OF THE I-AL80MN20 AND T-AL78MN22 QUASI-CRYSTALLINE PHASES SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. NORTHEASTERN UNIV,BOSTON,MA 02115. RP YANG, DP (reprint author), UNIV CONNECTICUT,STORRS,CT 06269, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5149 EP 5149 DI 10.1063/1.348107 PN 2A PG 1 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200259 ER PT J AU MACHADO, FLA MONTENEGRO, FC REZENDE, SM AZEVEDO, LJ CLARK, WG AF MACHADO, FLA MONTENEGRO, FC REZENDE, SM AZEVEDO, LJ CLARK, WG TI SPIN-GLASS BEHAVIOR IN THE AL-MN QUASI-CRYSTALLINE ALLOYS SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 SANDIA NATL LABS,DIV 3532,ALBUQUERQUE,NM 87185. UNIV CALIF LOS ANGELES,DEPT PHYS,LOS ANGELES,CA 90024. UNIV CALIF LOS ANGELES,CTR SOLID STATE SCI,LOS ANGELES,CA 90024. RP MACHADO, FLA (reprint author), UNIV FED PERNAMBUCO,DEPT FIS,BR-50739 RECIFE,PE,BRAZIL. RI Rezende, Sergio/G-4570-2014 OI Rezende, Sergio/0000-0002-3806-411X NR 3 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5150 EP 5150 DI 10.1063/1.348108 PN 2A PG 1 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200260 ER PT J AU FREEMAN, AJ LI, C AF FREEMAN, AJ LI, C TI MAGNETIC-ANISOTROPY OF FERROMAGNETIC FE AND CO THIN-FILMS SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 ARGONNE NATL LAB,ARGONNE,IL 60439. RP FREEMAN, AJ (reprint author), NORTHWESTERN UNIV,EVANSTON,IL 60208, USA. NR 1 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5215 EP 5215 DI 10.1063/1.348079 PN 2A PG 1 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200285 ER PT J AU SAID, MR KOUVEL, JS BRUN, TO AF SAID, MR KOUVEL, JS BRUN, TO TI ROTATIONAL SPIN-GLASS PROPERTIES OF NEARLY FERROMAGNETIC TB0.15Y0.85ZN SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID NI-MN; TB0.3Y0.7AG; ANISOTROPY; ALLOYS AB For this cubic pseudobinary compound, the bifurcation of the magnetization (M) vs temperature for warming and cooling in low fields (after zero-field cooling) indicates a spin-glass freezing point (T(g)) of approximately 20 K. Isotherms of M vs cooling field show zero spontaneous moments down to 4.2 K but an initial susceptibility that almost diverges below T(g). From rotational measurements of M as a vector in a fixed field (H) at 4.2 K, the anisotropy field produced by field cooling (H(K)) is found to turn rigidly with the sample for H below approximately 1 kOe. At higher H, H(K) rotates up to some angle relative to H and then stays fixed as the sample continues to turn, thus exhibiting a fractional rotation relative to the sample. Nevertheless, H(K) remains sizeable in magnitude (approximately 12 kOe). Comparisons are made with analogous results for isostructural (Tb, Y) Ag, where spin-glass order coexists with antiferromagnetism, as well as for various prototypal spin-glass alloys. C1 UNIV ILLINOIS, DEPT PHYS, CHICAGO, IL 60680 USA. UNIV CALIF LOS ALAMOS SCI LAB, PLANSCE, LOS ALAMOS, NM 87545 USA. NR 11 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5243 EP 5245 DI 10.1063/1.348092 PN 2A PG 3 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200298 ER PT J AU CAREY, MJ PARKER, FT BERKOWITZ, AE LEROUX, C AF CAREY, MJ PARKER, FT BERKOWITZ, AE LEROUX, C TI LONG-RANGE MAGNETIC ORDER IN NONPERCOLATING ANTIGRANULOCYTES FE-SIO2 THIN-FILMS SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 UNIV CALIF SAN DIEGO,CTR MAGNET RECORDING RES,LA JOLLA,CA 92093. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,NATL CTR ELECTRON MICROSCOPY,BERKELEY,CA 94720. RP CAREY, MJ (reprint author), UNIV CALIF SAN DIEGO,DEPT PHYS,R-001,LA JOLLA,CA 92093, USA. RI christine, leroux/H-4635-2013 OI christine, leroux/0000-0003-4649-9305 NR 2 TC 5 Z9 5 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5282 EP 5282 DI 10.1063/1.348049 PN 2A PG 1 WC Physics, Applied SC Physics GA FL732 UT WOS:A1991FL73200309 ER PT J AU DAWSON, WK LAM, JC BOEKEMA, C LICHTI, RL COOKE, DW CROW, JE AF DAWSON, WK LAM, JC BOEKEMA, C LICHTI, RL COOKE, DW CROW, JE TI ZERO-FIELD MUON-SPIN RELAXATION IN (Y1-XPRX)BA2CU3OY SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID MAGNETIC ORDER; SUPERCONDUCTIVITY; CU; ANTIFERROMAGNETISM; PRBA2CU3O7; OXYGEN AB Results of zero-field muon-spin-relaxation (mu-SR) experiments of Y(1-x)Pr(x)Ba2Cu3O(y) [(Y(1-x)Pr(x))1237; 0.5 < x less-than-or-equal-to 1.0, y = 7; x = 1, y = 6] are examined in light of the observed magnetism and the candidate mu-probe site. A mu-SR frequency signal near 2 MHz (extrapolated to 0 K) has been found for 0.5 << x less-than-or-equal-to 1, y = 7, and z = 0.08, y = 7, representing a local magnetic field of about 0.15 kOe at the established B2 mu-probe site. For x near 1.0 (z = 0), a shift in mu-SR frequency of about -0.4 MHz has been observed near T(N2)(x). Between T(N2) and T(N1), the magnetism is due to antiferromagnetic ordering of the Cu moments in the CuO2 planes. No frequency shifts have been observed for Pr1236 at its T(N2). The anomalous frequency shift for (Pr(x)Y1-x)237 can be due to additional Cu-chain antiferromagnetism and/or attributable to additional Pr magnetism. C1 TEMPLE UNIV,PHILADELPHIA,PA 19122. TEXAS TECH UNIV,LUBBOCK,TX 79409. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RP DAWSON, WK (reprint author), SAN JOSE STATE UNIV,DEPT PHYS,SAN JOSE,CA 95192, USA. NR 23 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5385 EP 5387 DI 10.1063/1.348040 PN 2B PG 3 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500020 ER PT J AU MOOK, HA AF MOOK, HA TI RECENT NEUTRON STUDIES OF HIGH-TC MATERIALS SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract RP MOOK, HA (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5391 EP 5391 DI 10.1063/1.348042 PN 2B PG 1 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500022 ER PT J AU DIERKER, SB ARONSON, MC DENNIS, BS CHEONG, SW FISK, Z AF DIERKER, SB ARONSON, MC DENNIS, BS CHEONG, SW FISK, Z TI EFFECTS OF PRESSURE ON SPIN FLUCTUATIONS AND THE EXCHANGE INTERACTION IN LA2CUO4 AS DETERMINED BY 2-MAGNON RAMAN-SCATTERING SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 AT&T BELL LABS,TECH STAFF,MURRAY HILL,NJ 07974. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RP DIERKER, SB (reprint author), UNIV MICHIGAN,RANDALL LAB PHYS,DEPT PHYS,ANN ARBOR,MI 48109, USA. NR 0 TC 0 Z9 0 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5392 EP 5392 DI 10.1063/1.348015 PN 2B PG 1 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500024 ER PT J AU KIOUSSIS, N SWEARINGEN, D COOPER, BR WILLS, JM AF KIOUSSIS, N SWEARINGEN, D COOPER, BR WILLS, JM TI TRENDS OF HYBRIDIZATION-INDUCED MAGNETISM IN CERIUM MONOCHALCOGENIDES SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID SYSTEMS; MODEL; CESB; BAND AB A synthesis of ab initio linear-muffin-tin-orbital (LMTO) electronic structure calculations and a phenomenological model of orbitally driven magnetic ordering has been applied to investigate trends of the effect of hybridization of moderately delocalized f electrons with band electrons on the diverse magnetic behavior across the cerium monochalcogenide series. The parameters entering the Anderson lattice model Hamiltonian are determined from total-energy supercell warped-muffin-tin LMTO calculations with zero, one, and two electrons in the cerium 4f core state. The origins, in the electronic structure, of the variation of the density of states at the Fermi energy, the f-state resonance width, the hybridization potential, the hybridization-dressed crystal-field splitting, and the hybridization-mediated exchange interactions with the chemical environment (anion size) on going down the chalcogen column have been investigated systematically, increasing thus the degree of f-electron localization as the cerium-cerium separation increases. C1 W VIRGINIA UNIV,DEPT PHYS,MORGANTOWN,WV 26506. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RP KIOUSSIS, N (reprint author), CALIF STATE UNIV NORTHRIDGE,DEPT PHYS,NORTHRIDGE,CA 91330, USA. NR 16 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5475 EP 5477 DI 10.1063/1.347970 PN 2B PG 3 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500053 ER PT J AU HEFFNER, RH BEYERMANN, WP HUNDLEY, MF THOMPSON, JD SMITH, JL FISK, Z BEDELL, K BIRRER, P BAINES, C GYGAX, FN HITTI, B LIPPELT, E OTT, HR SCHENCK, A MACLAUGHLIN, DE AF HEFFNER, RH BEYERMANN, WP HUNDLEY, MF THOMPSON, JD SMITH, JL FISK, Z BEDELL, K BIRRER, P BAINES, C GYGAX, FN HITTI, B LIPPELT, E OTT, HR SCHENCK, A MACLAUGHLIN, DE TI THERMODYNAMICS AND MAGNETISM IN U1-XTHXBE13-YBY SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC AB We report specific heat and mu-SR measurements on Th (x = 0.019) and/or B (y = 0.03) substituted UBe13. The specific heat data show that either Th or B substitution reduces the Kondo temperature T(K) and increases the entropy at the superconducting transition by almost 20%, indicating an enhanced density of states. However, whereas mu-SR shows clear evidence for magnetic correlations for Th substitutions (0.019 < x < 0.043), no magnetism is observed for B substitutions. The enhanced specific heat jump in the B-substituted material is associated with a change in the superconducting properties as T(K) is reduced. C1 PAUL SCHERRER INST,VILLIGEN,SWITZERLAND. SWISS FED INST TECHNOL,CH-8092 ZURICH,SWITZERLAND. UNIV CALIF RIVERSIDE,DEPT PHYS,RIVERSIDE,CA 92521. RP HEFFNER, RH (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,P-10,MS K764,LOS ALAMOS,NM 87545, USA. NR 6 TC 11 Z9 11 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5481 EP 5483 DI 10.1063/1.347972 PN 2B PG 3 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500055 ER PT J AU ARONSON, MC VORENKAMP, T KOZIOL, Z DEVISSER, A BAKKER, K FRANSE, JJM SMITH, JL AF ARONSON, MC VORENKAMP, T KOZIOL, Z DEVISSER, A BAKKER, K FRANSE, JJM SMITH, JL TI IMPURITY EFFECTS IN SUPERCONDUCTING UPT3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID PHASE-DIAGRAM; HEAT; FIELD; MODEL AB Superconducting UPt3 is characterized by a novel and complex magnetic field-temperature phase diagram, with two superconducting transitions at T(c1) and T(c2) in zero field. We have studied the effects of Pd and Y impurities on the zero field superconducting properties of UPt3. Resistance measurements show that both dopants increase the residual resistivity and decrease the spin fluctuation temperature in the normal state. T(c1) is depressed by both dopants, but more effectively by Pd. \T(c1) - T(c2)\ is essentially unaffected by Y doping, but increases dramatically with Pd doping. C1 UNIV AMSTERDAM,NAT KUNDIG LAB,1018 XE AMSTERDAM,NETHERLANDS. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RP ARONSON, MC (reprint author), UNIV MICHIGAN,RANDALL LAB PHYS,ANN ARBOR,MI 48109, USA. NR 16 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5487 EP 5489 DI 10.1063/1.347973 PN 2B PG 3 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500057 ER PT J AU BROHOLM, C AEPPLI, G KLEIMAN, RN HARSHMAN, DR BISHOP, DJ BUCHER, E WILLIAMS, DL ANSALDO, EJ HEFFNER, RH AF BROHOLM, C AEPPLI, G KLEIMAN, RN HARSHMAN, DR BISHOP, DJ BUCHER, E WILLIAMS, DL ANSALDO, EJ HEFFNER, RH TI SUPERCONDUCTIVITY OF UPT3 STUDIED BY MU+SR AND NEUTRON-SCATTERING SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 UNIV BRITISH COLUMBIA,VANCOUVER V6T 2A6,BC,CANADA. UNIV SASKATCHEWAN,SASKATOON S7N 0W0,SASKATCHEWAN,CANADA. UNIV CONSTANCE,W-7750 CONSTANCE,GERMANY. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. RP BROHOLM, C (reprint author), AT&T BELL LABS,MURRAY HILL,NJ 07974, USA. RI Broholm, Collin/E-8228-2011 OI Broholm, Collin/0000-0002-1569-9892 NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5491 EP 5491 DI 10.1063/1.347976 PN 2B PG 1 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500060 ER PT J AU WATSON, RE FERNANDO, GW WEINERT, M WANG, YJ DAVENPORT, JW AF WATSON, RE FERNANDO, GW WEINERT, M WANG, YJ DAVENPORT, JW TI COHESION AND PROMOTION ENERGIES IN THE TRANSITION-METALS - IMPLICATIONS OF THE LOCAL-DENSITY APPROXIMATION SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID STRUCTURAL-PROPERTIES; FULL AB The accuracy of the local-density (LDA) or local-spin-density (LSDA) approximations when applied to transition metals is of great concern. Estimates of the cohesive energy compare the total energy of the solid with that of the free atom. This involves chosing the reference state of the free atom which, as a rule, will not be the free atom's ground state in LDA or LSDA. Comparing one reference state versus another, e.g., the d(n-1)s vs d(n-2)s2 for a transition metal, corresponds to calculating an s-d promotion energy DELTA, which may be compared with experiment. Gunnarsson and Jones (GJ) [Phys. Rev. B 31, 7588 (1985)] found for the 3d row that the calculated DELTA displayed systematic errors which they attributed to a difference in error within the LSDA in the treatment of the coupling of the outer-core electrons with the d versus non-d valence electrons. This study has been extended to relativistic calculations for the 3d, 4d, and 5d rows and for other promotions. The situation is more complicated than suggested by GJ, and its implications for cohesive energy estimates will be discussed. RP WATSON, RE (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5688 EP 5690 DI 10.1063/1.347912 PN 2B PG 3 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500131 ER PT J AU MARCHON, B HEIMAN, N KHAN, MR LAUTIE, A AGER, JW VEIRS, DK AF MARCHON, B HEIMAN, N KHAN, MR LAUTIE, A AGER, JW VEIRS, DK TI RAMAN AND RESISTIVITY INVESTIGATIONS OF CARBON OVERCOATS OF THIN-FILM MEDIA - CORRELATIONS WITH TRIBOLOGICAL PROPERTIES SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID AMORPHOUS-CARBON; GRAPHITE; SPECTROSCOPY; DISKS; WEAR AB Tribological measurements have been performed on a series of carbon films deposited on untextured 95-mm magnetic disks by magnetron sputtering. Raman spectra and resistivity data of these films have been correlated to friction and wear performance. Tribochemical wear, as estimated by the rate of frictional buildup, is correlated to the G-band position in the Raman spectrum. Abrasive wear is best correlated to the I(D)/I(G) intensity ratio of the D and G bands, as well as to electrical resistivity. Interpretation of these data using structural models of amorphous carbon films is discussed. C1 CNRS,LASIR,F-94320 THIAIS,FRANCE. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. RP MARCHON, B (reprint author), SEAGATE MAGNET,FREMONT,CA 94538, USA. RI Marchon, Bruno/H-5665-2013; OI Ager, Joel/0000-0001-9334-9751 NR 18 TC 42 Z9 42 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5748 EP 5750 DI 10.1063/1.347909 PN 2B PG 3 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500153 ER PT J AU JILES, DC THOELKE, JB AF JILES, DC THOELKE, JB TI A 3D ANISOTROPIC ROTATION MODEL FOR MAGNETIZATION AND MAGNETOSTRICTION IN TB0.3DY0.7FE1.9 SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract RP JILES, DC (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. RI Jiles, David/H-9548-2012 NR 1 TC 0 Z9 0 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5797 EP 5797 DI 10.1063/1.347880 PN 2B PG 1 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500174 ER PT J AU ERIKSSON, O BROOKS, MSS JOHANSSON, B ALBERS, RC BORING, AM AF ERIKSSON, O BROOKS, MSS JOHANSSON, B ALBERS, RC BORING, AM TI MAGNETISM AND BONDING IN LIGHT ACTINIDE AND RARE-EARTH SYSTEMS SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID ELECTRONIC-STRUCTURE; METALS; UFE2; ENERGIES; PU AB The importance of including all of Hund's rules in self-consistent electronic-structure calculations in solids is pointed out. We present a scheme that accounts for the interactions that lead to these rules, and we give examples of when these interactions become important. Calculated ground state properties (chemical bonding, magnetic moment, magnetic form factor) of actinide and rare earth systems are found to agree better with experiment when all Hund's rules are accounted for. On the other hand, but also in agreement with experiment, we find that Hund's second and third rule contributions for Fe, Co, and Ni are small. C1 UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP ERIKSSON, O (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,CTR MAT SCI,LOS ALAMOS,NM 87545, USA. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 30 TC 18 Z9 18 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5897 EP 5902 DI 10.1063/1.347865 PN 2B PG 6 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500211 ER PT J AU NORMAN, MR AF NORMAN, MR TI ORBITAL POLARIZATION TRANSITION-METAL OXIDES SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract RP NORMAN, MR (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Norman, Michael/C-3644-2013 NR 2 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5909 EP 5909 DI 10.1063/1.347835 PN 2B PG 1 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500213 ER PT J AU MCWHAN, DB AF MCWHAN, DB TI SEPARATION OF SPIN AND ORBITAL MOMENTS BY SYNCHROTRON X-RAY-SCATTERING SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract RP MCWHAN, DB (reprint author), BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973, USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5910 EP 5910 DI 10.1063/1.347836 PN 2B PG 1 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500214 ER PT J AU LIN, HQ CAMPBELL, DK AF LIN, HQ CAMPBELL, DK TI SPIN-SPIN CORRELATIONS IN THE ONE-DIMENSIONAL SPIN-1/2 ANTIFERROMAGNETIC HEISENBERG CHAIN SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID CARLO AB We have calculated the spin-spin correlations in the ground state of spin-1/2, one-dimensional, antiferromagnetic Heisenberg chain numerically. Using improved algorithms, we have been able to perform exact diagonalizations for lattices up to 30 sites and quantum Monte Carlo simulations for lattices up to 512 sites. This extensive range allows us to investigate the logarithmic dependence of spin-spin correlations. We present our results and discuss their implications. RP LIN, HQ (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545, USA. NR 12 TC 17 Z9 17 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 5947 EP 5949 DI 10.1063/1.347825 PN 2B PG 3 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500228 ER PT J AU TAYLOR, RD PASTERNAK, MP JEANLOZ, R AF TAYLOR, RD PASTERNAK, MP JEANLOZ, R TI HYSTERESIS IN THE HIGH-PRESSURE TRANSFORMATION OF BCC-IRON TO HCP-IRON SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID EPSILON-FE AB The alpha-Fe/member-of-Fe phase transformation has been studied by the Mossbauer effect of Fe-57 in a diamond anvil cell at hydrostatic pressures up to 24 GPa. The alpha/member-of composition is easily derived as a function of intermediate pressure. For rising pressures the transition onset is about 9 GPa and half of the alpha-Fe is converted to member-of-Fe by 15 GPa; for lowering pressures half of the member-of-Fe is converted to alpha-Fe by 9 GPa. The transition pressures, widths, and hysteresis widths are compared to those obtained by other techniques. C1 UNIV CALIF BERKELEY,DEPT GEOL & GEOPHYS,BERKELEY,CA 94720. RP TAYLOR, RD (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV PHYS,LOS ALAMOS,NM 87545, USA. NR 15 TC 88 Z9 90 U1 1 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 6126 EP 6128 DI 10.1063/1.348779 PN 2B PG 3 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500294 ER PT J AU CABLE, JW GILLON, B MIREBEAU, I PARETTE, G NAKAI, Y AF CABLE, JW GILLON, B MIREBEAU, I PARETTE, G NAKAI, Y TI ATOMIC AND MAGNETIC SPATIAL CORRELATIONS IN FE-13.5-PERCENT-V SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 OSAKA UNIV,OSAKA,JAPAN. CENS,LAB LEON BRILLOUIN,F-91190 GIF SUR YVETTE,FRANCE. RP CABLE, JW (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 1 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 6150 EP 6150 DI 10.1063/1.348787 PN 2B PG 1 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500302 ER PT J AU JOHNSON, DD STAUNTON, JB PINSKI, FJ AF JOHNSON, DD STAUNTON, JB PINSKI, FJ TI 1ST-PRINCIPLES CALCULATIONS OF CHEMICAL AND MAGNETIC CORRELATIONS IN FE-13.5-PERCENT-V SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 UNIV WARWICK,COVENTRY CV4 7AL,W MIDLANDS,ENGLAND. UNIV CINCINNATI,CINCINNATI,OH 45221. RP JOHNSON, DD (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 6151 EP 6151 DI 10.1063/1.348788 PN 2B PG 1 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500303 ER PT J AU PERRING, TG BOOTHROYD, AT PAUL, DM TAYLOR, AD OSBORN, R NEWPORT, RJ BLACKMAN, JA MOOK, HA AF PERRING, TG BOOTHROYD, AT PAUL, DM TAYLOR, AD OSBORN, R NEWPORT, RJ BLACKMAN, JA MOOK, HA TI HIGH-ENERGY SPIN-WAVES IN BCC IRON SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 35TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY OCT 29-NOV 01, 1990 CL SAN DIEGO, CA SP AMER INST PHYS, IEEE, MAGNET SOC, AMER INST MIN MET & PETR ENGINEERS, MET SOC, USN, OFF NAVAL RES, AMER SOC TESTING & MAT, AMER PHYS SOC, AMER CERAM SOC ID MAGNETIC EXCITATIONS AB The dispersion relation of the spin-wave excitations in bcc iron has been studied by neutron inelastic scattering at the spallation neutron source ISIS. Magnetic intensity was followed up to 550 meV along the [100] direction. The general form of the dispersion curve is in qualitative agreement with that calculated from a spin-polarized band model, and in particular the prediction of propagating modes extending above 300 meV has been confirmed. C1 UNIV WARWICK,DEPT PHYS,COVENTRY CV3 6NT,ENGLAND. RUTHERFORD APPLETON LAB,DIDCOT OX11 0QX,OXON,ENGLAND. UNIV KENT,DEPT PHYS,CANTERBURY CT2 7NR,ENGLAND. UNIV READING,DEPT PHYS,READING RG6 2AF,BERKS,ENGLAND. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP PERRING, TG (reprint author), UNIV OXFORD,CLARENDON LAB,PARKS RD,OXFORD,ENGLAND. RI Osborn, Raymond/E-8676-2011; Newport, Robert/C-9973-2012 OI Osborn, Raymond/0000-0001-9565-3140; Newport, Robert/0000-0002-2365-992X NR 7 TC 23 Z9 23 U1 1 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1991 VL 69 IS 8 BP 6219 EP 6221 DI 10.1063/1.348814 PN 2B PG 3 WC Physics, Applied SC Physics GA FL735 UT WOS:A1991FL73500329 ER PT J AU CUMMINGS, PT COCHRAN, HD SIMONSON, JM MESMER, RE KARABORNI, S AF CUMMINGS, PT COCHRAN, HD SIMONSON, JM MESMER, RE KARABORNI, S TI SIMULATION OF SUPERCRITICAL WATER AND OF SUPERCRITICAL AQUEOUS-SOLUTIONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS; LIQUID WATER; COMPUTER-SIMULATIONS; FLUID MIXTURES; CRITICAL-POINT; SYSTEMS; DILUTE; VOLUMES; STATE AB Molecular dynamics (MD) calculations have been performed to determine equilibrium structure and properties of systems modeling supercritical (SC) water and SC aqueous solutions at two states near the critical point using the simple point charge (SPC) potential model of Berendsen et al. for water. Both thermodynamic and dielectric properties from the simulations for pure water are accurate in comparison with experimental results even though the SPC model parameters were fitted to properties of ambient water. Details of the near-critical clustering in SC water have been predicted which have not been measured to date. MD studies have also been undertaken of systems that model sodium and chloride ions and neutral argon in SC water at the same states. The first solvation shell in SC water is observed to be similar to that in ambient water, and long-range solvation structures in SC water are similar to those observed for simple SC solvents. An excess of water molecules is observed clustering around ionic solutes which behave attractively and a deficit is observed around neutral atomic solutes which behave repulsively. These results should be helpful in developing a qualitative understanding of important processes that occur in SC water. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. UNIV VIRGINIA,DEPT CHEM ENGN,CHARLOTTESVILLE,VA 22901. RP CUMMINGS, PT (reprint author), UNIV VIRGINIA,DEPT CHEM ENGN,CHARLOTTESVILLE,VA 22901, USA. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 44 TC 173 Z9 174 U1 1 U2 18 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 15 PY 1991 VL 94 IS 8 BP 5606 EP 5621 DI 10.1063/1.460497 PG 16 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA FH076 UT WOS:A1991FH07600042 ER PT J AU SPITZIG, WA PETERSON, DT LAABS, FC AF SPITZIG, WA PETERSON, DT LAABS, FC TI EFFECT OF HYDROGEN ON THE MECHANICAL-PROPERTIES OF A DEFORMATION PROCESSED CU-20-PERCENT NB COMPOSITE SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID MULTIFILAMENTARY COMPOSITES; STRENGTH; ALLOYS; MICROSTRUCTURE; RESISTIVITY; COPPER AB The influence of H on the mechanical properties of a deformation processed Cu-20% Nb composite was analysed and compared with the results on similarly processed pure Cu and pure Nb. In this composite the matrix phase (Cu) is relatively resistant to H while the filamentary phase (Nb) is highly susceptible to H embrittlement. The results show that H, in an amount equivalent to that which causes embrittlement of pure Nb, causes no significant deleterious influence on the mechanical properties of Cu-20% Nb. Apparently the ductile Cu matrix creates a favourable stress state for the hydrogenated Nb filaments so that they are constrained from fracturing and continue to deform in a ductile manner. RP SPITZIG, WA (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,DIV MET & CERAM,AMES,IA 50011, USA. NR 18 TC 4 Z9 4 U1 0 U2 0 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD APR 15 PY 1991 VL 26 IS 8 BP 2000 EP 2006 DI 10.1007/BF00549158 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA FH280 UT WOS:A1991FH28000002 ER PT J AU MORSS, LR CARNALL, WT WILLIAMS, CW FAHEY, JA FUGER, J MEYER, G IRMLER, M AF MORSS, LR CARNALL, WT WILLIAMS, CW FAHEY, JA FUGER, J MEYER, G IRMLER, M TI SYNTHESES AND X-RAY-DIFFRACTION STUDIES OF [N(CH3)4]2BKCL6 AND [N(CH3)4]2ZRCL6 - ABSORPTION-SPECTRUM OF BK4+ IN [N(CH3)4]2BKCL6 SO JOURNAL OF THE LESS-COMMON METALS LA English DT Article ID CRYSTAL-STRUCTURE AB [N(CH3)4]2BkCl6 was synthesized from cold, concentrated HCl(aq) using 249Bk (t1/2 = 320 days) separated from 249Cf on the milligram scale. For comparison [N(CH3)4]2ZrCl6 was also synthesized and single crystals were grown. Both compounds were studied by X-ray powder diffraction, and [N(CH3)4]2ZrCl6 was also studied by single-crystal X-ray diffraction. Powder patterns of [N(CH3)4]2BkCl6 have f.c.c. symmetry, a = 13.08(2) angstrom, isostructural with K2PtCl6 and other [N(CH3)4]2MCl6 salts. [N(CH3)4]2ZrCl6 has f.c.c. symmetry, space group Fm3m (disregarding hydrogen positions) with a = 12.882(1) angstrom and d(Zr-Cl) = 2.428(8) angstrom. A transition to lower symmetry was found in [N(CH3)4]2ZrCl6 at -110-degrees-C by Guinier powder diffraction. Optical spectra of Bk4+ in [N(CH3)4]2BkCl6 in KBr and KCl pellets were recorded and interpreted. C1 CUNY BRONX COMMUNITY COLL,DEPT CHEM,BRONX,NY 10453. UNIV HANOVER,INST ANORGAN CHEM,W-3000 HANNOVER,GERMANY. RP MORSS, LR (reprint author), ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439, USA. NR 18 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0022-5088 J9 J LESS-COMMON MET PD APR 15 PY 1991 VL 169 IS 1 BP 1 EP 8 DI 10.1016/0022-5088(91)90229-W PG 8 WC Chemistry, Physical; Metallurgy & Metallurgical Engineering SC Chemistry; Metallurgy & Metallurgical Engineering GA FJ574 UT WOS:A1991FJ57400005 ER PT J AU ZHANG, DY TANG, JK GSCHNEIDNER, KA AF ZHANG, DY TANG, JK GSCHNEIDNER, KA TI A REDETERMINATION OF THE LA-NI PHASE-DIAGRAM FROM LANI TO LANI5 (50-83.3 AT PERCENT-NI) SO JOURNAL OF THE LESS-COMMON METALS LA English DT Article ID HYDROGEN AB The La-Ni phase diagram was re-investigated over the composition range (50-83.3 at.% Ni). The major changes from the earlier published phase diagrams are: (1) the non-existence of the LaNi2 Laves phase as an equilibrium phase; (2) the existence of La0.875Ni2 (LaNi2.286), a pseudo-Laves-like phase; (3) the liquidus region between 58 and 70 at.% Ni; the alpha-beta transformation in La2Ni7 at 976-degrees-C (previously no transformation was reported); and (4) the peritectic melting temperature for LaNi3 at 811-degrees-C (previously reported at 975-degrees-C). Minor differences were found for several invariant temperature horizontals (eutectic and peritectic temperatures) and the compositions of the LaNi-"La2Ni3" eutectic and the so-called "La2Ni3" phase. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT MAT SCI & ENGN,AMES,IA 50011. RP ZHANG, DY (reprint author), SHANGHAI YUE LONG NONFERROUS MET LTD,SHANGHAI,PEOPLES R CHINA. NR 16 TC 43 Z9 45 U1 1 U2 3 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0022-5088 J9 J LESS-COMMON MET PD APR 15 PY 1991 VL 169 IS 1 BP 45 EP 53 PG 9 WC Chemistry, Physical; Metallurgy & Metallurgical Engineering SC Chemistry; Metallurgy & Metallurgical Engineering GA FJ574 UT WOS:A1991FJ57400010 ER PT J AU RAUBENHEIMER, TO RUTH, RD AF RAUBENHEIMER, TO RUTH, RD TI A DISPERSION-FREE TRAJECTORY CORRECTION TECHNIQUE FOR LINEAR COLLIDERS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB In this paper, we describe a new trajectory correction technique for high energy linear accelerators. Current correction techniques force the beam trajectory to follow misalignments of the beam position monitors (BPMs). Since the particle bunch has a finite energy spread and particles with different energies are deflected differently, this causes "chromatic" dilution of the transverse beam emittance. The algorithm which we describe in this paper reduces the chromatic dilution by minimizing the energy dependence of the trajectory. To test the method we compare the effectiveness of our algorithm with a standard correction technique in simulations of the Standford Linear Collider (SLC) linear accelerator and a design linac for a Next Linear Collider (NLC). While the simulations do not indicate that chromatic dilutions are a serious problem in the SLC linac, they would be debilitating in a future linear collider because of the very small beam sizes required to achieve the necessary luminosity. For example, in simulations of the NLC we have found that with typical alignment tolerances the beam size increased substantially after correcting the trajectory with a standard correction algorithm. In contrast, after correcting with our technique, the dilution was negligible. We feel that this technique will prove essential for future linear colliders. RP RAUBENHEIMER, TO (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 16 TC 21 Z9 21 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 1991 VL 302 IS 2 BP 191 EP 208 DI 10.1016/0168-9002(91)90403-D PG 18 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FN899 UT WOS:A1991FN89900001 ER PT J AU LINDSEY, CS DENBY, B AF LINDSEY, CS DENBY, B TI PRIMARY VERTEX FINDING IN PROTON-ANTIPROTON EVENTS WITH A NEURAL NETWORK SIMULATION SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB In a test of neural networks in high energy physics pattern recognition problems, drift chamber data from experiment E735 at the Tevatron proton-antiproton collider was used in a neural network simulation to find the primary event vertex. A three layer, feed-forward neural network was trained with the back-propagation technique to give the beam line vertices of tracks traversing subsections of the chamber. Summing the outputs of all subsection networks then gives the primary vertex along the beam line. Results are compared to conventional methods. RP LINDSEY, CS (reprint author), FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. NR 12 TC 7 Z9 7 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 1991 VL 302 IS 2 BP 217 EP 226 DI 10.1016/0168-9002(91)90405-F PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FN899 UT WOS:A1991FN89900003 ER PT J AU KING, BJ ARROYO, CG BACHMANN, KT BLAIR, RE FOUDAS, C LEFMANN, WC LEUNG, WC MISHRA, SR OLTMAN, E QUINTAS, PZ RABINOWITZ, SA SCIULLI, FJ SELIGMAN, WG SHAEVITZ, MH MERRITT, FS OREGLIA, MJ SCHUMM, BA BERNSTEIN, RH BORCHERDING, F FISK, HE LAMM, MJ MARSH, W MERRITT, KWB SCHELLMAN, H YOVANOVITCH, DD BODEK, A BUDD, HS DEBARBARO, P SAKUMOTO, WK SANDLER, PH SMITH, WH AF KING, BJ ARROYO, CG BACHMANN, KT BLAIR, RE FOUDAS, C LEFMANN, WC LEUNG, WC MISHRA, SR OLTMAN, E QUINTAS, PZ RABINOWITZ, SA SCIULLI, FJ SELIGMAN, WG SHAEVITZ, MH MERRITT, FS OREGLIA, MJ SCHUMM, BA BERNSTEIN, RH BORCHERDING, F FISK, HE LAMM, MJ MARSH, W MERRITT, KWB SCHELLMAN, H YOVANOVITCH, DD BODEK, A BUDD, HS DEBARBARO, P SAKUMOTO, WK SANDLER, PH SMITH, WH TI MEASURING MUON MOMENTA WITH THE CCFR NEUTRINO DETECTOR SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB We report on muon spectrometry at the CCFR neutrino detector. The muon spectrometer and momentum-fitting analysis code are described, and results presented from the calibration of the spectrometer with test beams of momentum-analyzed muons. C1 UNIV CHICAGO,CHICAGO,IL 60637. FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. UNIV ROCHESTER,ROCHESTER,NY 14627. UNIV WISCONSIN,MADISON,WI 53706. RP KING, BJ (reprint author), COLUMBIA UNIV,NEW YORK,NY 10027, USA. OI Bernstein, Robert/0000-0002-7610-950X NR 7 TC 38 Z9 38 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 1991 VL 302 IS 2 BP 254 EP 260 DI 10.1016/0168-9002(91)90408-I PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FN899 UT WOS:A1991FN89900006 ER PT J AU DOKE, T CRAWFORD, HJ ENGELAGE, JM FLORES, I GREINER, L KASHIWAGI, T KIKUCHI, J MASUDA, K NISHIJIMA, K SHIBAMURA, E SYMONS, TJM AF DOKE, T CRAWFORD, HJ ENGELAGE, JM FLORES, I GREINER, L KASHIWAGI, T KIKUCHI, J MASUDA, K NISHIJIMA, K SHIBAMURA, E SYMONS, TJM TI SAMPLING CALORIMETER FOR HIGH-ENERGY HEAVY-PARTICLES FILLED WITH ALLENE-DOPED LIQUID ARGON SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID ION EXPERIMENT WA80; IONIZATION; SCINTILLATION; RESOLUTION; CERN AB A hadron calorimeter for investigating relativistic heavy ion reactions, filled with liquid argon doped with allene, has been tested for 1 GeV/n neon and iron ions, and 1.7 GeV/n helium, neon and iron ions. The electrode system of the calorimeter consists of G-10 plates placed in the first, second and third parts, 2 mm thick iron plates in the second part and 6 mm thick iron plates in the third part with a liquid argon gap of 3.5 mm. Some of the ions were stopped inside the calorimeter without fragmentation, which were treated separately. The calorimeter shows a good linear response to the total incident energy of ions for fragmented and stopped ions. The absolute yields of collected charge are consistent with the calculated values. An energy resolution in FWHM of 2-5% is obtained for stopped ions. For fragmented ions, the energy resolution in FWHM is given by [0.9 + 81.1/square-root E(GeV)]% for all relativistic ions and if the datum of helium ions is excluded, the resolution can be expressed by [4.8 + 53.2/square-root E(GeV)]%. The present energy resolution is better than those recently obtained with scintillation calorimeters at BNL and CERN. C1 UNIV CALIF BERKELEY,SPACE SCI LAB,BERKELEY,CA 94720. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. SAITAMA COLL HLTH,URAWA,SAITAMA 338,JAPAN. RP DOKE, T (reprint author), WASEDA UNIV,SCI & ENGN RES LAB,KIKUICHO 17,SHINJUKU KU,TOKYO 162,JAPAN. NR 21 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 1991 VL 302 IS 2 BP 290 EP 300 DI 10.1016/0168-9002(91)90412-J PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FN899 UT WOS:A1991FN89900010 ER PT J AU BERKOVITS, D BOARETTO, E HOLLOS, G KUTSCHERA, W NAAMAN, R PAUL, M VAGER, Z AF BERKOVITS, D BOARETTO, E HOLLOS, G KUTSCHERA, W NAAMAN, R PAUL, M VAGER, Z TI OBSERVATION OF HIGH-INTENSITY NEGATIVE-ION PULSES BY LASER IMPACT SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Letter ID MASS-SPECTROMETRY AB We report on the observation of intense pulses of sulphur negative ions extracted from a Cs-beam sputter source and produced by the impact of 532 nm photon pulses from a Nd-YAG laser on a FeS cathode. Peak currents of about 3 mA are obtained after extraction and preacceleration of the negative ions, which are subsequently analyzed by accelerator mass spectrometry. The time structure of the S-32- negative ion current is measured and shows a complex behavior not yet fully understood. C1 WEIZMANN INST SCI,ACCELERATOR LAB,IL-76100 REHOVOT,ISRAEL. ARGONNE NATL LAB,ARGONNE,IL 60439. WEIZMANN INST SCI,ISOTOPE RES DEPT,IL-76100 REHOVOT,ISRAEL. WEIZMANN INST SCI,DEPT NUCL PHYS,IL-76100 REHOVOT,ISRAEL. RP BERKOVITS, D (reprint author), HEBREW UNIV JERUSALEM,RACAH INST PHYS,IL-91904 JERUSALEM,ISRAEL. 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 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 1991 VL 302 IS 2 BP 379 EP 381 DI 10.1016/0168-9002(91)90426-Q PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA FN899 UT WOS:A1991FN89900024 ER PT J AU LANDEN, OL SZOKE, A AF LANDEN, OL SZOKE, A TI ULTRAFAST GAIN QUENCHING IN LASER-AMPLIFIERS SO OPTICS LETTERS LA English DT Article ID DYE-LASER; PULSES; GENERATION; PLASMAS; DESIGN; SYSTEM AB A versatile and simple passive optical technique for quenching gain in laser amplifiers on picosecond and subpicosecond time scales is described. The scheme can be used to eliminate undesirable postpulses or to reduce laser pulse widths. A 30-fold suppression of satellite pulses from a synchronously pumped amplified dye laser is demonstrated. RP LANDEN, OL (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,POB 5508,LIVERMORE,CA 94550, USA. NR 18 TC 3 Z9 3 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD APR 15 PY 1991 VL 16 IS 8 BP 590 EP 592 DI 10.1364/OL.16.000590 PG 3 WC Optics SC Optics GA FG121 UT WOS:A1991FG12100018 PM 19774008 ER PT J AU MOROSIN, B VENTURINI, EL GINLEY, DS AF MOROSIN, B VENTURINI, EL GINLEY, DS TI ANNEALING STUDY ON SINGLE-CRYSTAL TL-2223 SUPERCONDUCTORS SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article ID OXYGEN STOICHIOMETRY; CU-O; TC; TL2BA2CA2CU3O10; TL2BA2CACU2O8; DIFFRACTION; CHAINS; PHASE AB We have shown that crystals in the Tl-Ca-Ba-Cu-O system are robust to anneals (oxygen, vacuum or 10%H2/90%N2) to 500-degrees-C. Improvements in the superconducting properties, as determined from Meissner data, are observed for anneals above 300-degrees-C and suggest that as-grown crystals may not have fully equilibrated during growth despite an extended cool down cycle. There appears to be no systematic shift in T(c) with oxygen content in the Tl-O layer. Single crystal X-ray structure refinements have determined small atomic displacements which, in part, suggest the possibility of small amounts of Tl1+ being present in the Tl-O layer of as-grown crystals which subsequently oxidizes during mild oxygen anneals to Tl3+. Hence, changes in oxygen content may not result in altered carrier concentration in the Cu-O layers. Further, the nature of the oxygen position in the Tl-O layer, as determined by the usual least-squares refinement of X-ray data, appears to be related to the amount of oxygen present in the particular sample. RP MOROSIN, B (reprint author), SANDIA NATL LABS, ALBUQUERQUE, NM 87185 USA. NR 28 TC 35 Z9 35 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD APR 15 PY 1991 VL 175 IS 3-4 BP 241 EP 249 DI 10.1016/0921-4534(91)90593-N PG 9 WC Physics, Applied SC Physics GA FJ347 UT WOS:A1991FJ34700002 ER PT J AU THEILHABER, J ALDER, BJ AF THEILHABER, J ALDER, BJ TI PATH-INTEGRAL SIMULATIONS OF HYDROGEN AND HYDROGEN PLASMAS SO PHYSICAL REVIEW A LA English DT Article ID MONTE-CARLO CALCULATION; QUANTUM-SYSTEMS; COMPUTATION; MOLECULES; DENSITY; MATTER AB Feynman path-integral simulations of a system consisting of protons and distinguishable electrons under periodic boundary conditions are presented with the aim of calculating the phase diagram of hydrogen at various temperatures and densities. For a two-electron-two-proton system, for which Fermi statistics can be ignored, the equations of state and the radial distribution functions are obtained, including the effects of temperature and pressure ionization, for temperatures down to 0.68 eV and densities up to 1 g cm-3. These results are compared to other models. Systems with more than two distinguishable electrons are found to be thermodynamically unstable, by collapsing into a cluster at low temperature, suggesting that further simulations be used to investigate the stability of Boltzmann matter. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. NR 27 TC 4 Z9 4 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR 15 PY 1991 VL 43 IS 8 BP 4143 EP 4155 DI 10.1103/PhysRevA.43.4143 PG 13 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FH612 UT WOS:A1991FH61200006 ER PT J AU ERPENBECK, JJ WOOD, WW AF ERPENBECK, JJ WOOD, WW TI SELF-DIFFUSION COEFFICIENT FOR THE HARD-SPHERE FLUID SO PHYSICAL REVIEW A LA English DT Article ID MOLECULAR-DYNAMICS CALCULATIONS; ASYMPTOTIC TIME BEHAVIOR; VELOCITY-CORRELATION FUNCTIONS; 3 DIMENSIONS; AUTOCORRELATION FUNCTION; FICKS LAW; TRANSPORT; EQUATION; DENSITY; TERMS AB Previously published Monte Carlo molecular-dynamics data on the velocity autocorrelation function of the hard-sphere fluid are supplemented by data for the time-dependent transport coefficient to yield estimates for the self-diffusion coefficient throughout the fluid regime, from 25 to 1.6 times the close-packed volume. The dependence on system size is explored through results for 108-4000 particles. It is found essential to include long-time contributions to the Green-Kubo integral based on the previously validated mode-coupling theory. It is shown that the calculations of Easteal, Woolf, and Jolly [Physica 121A, 286 (1983)] fall significantly below the current estimates, which are in qualitative agreement with the Alder, Gass, and Wainwright [J. Chem. Phys. 53, 3813 (1970)] values. RP ERPENBECK, JJ (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545, USA. NR 38 TC 105 Z9 107 U1 1 U2 16 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR 15 PY 1991 VL 43 IS 8 BP 4254 EP 4261 DI 10.1103/PhysRevA.43.4254 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FH612 UT WOS:A1991FH61200020 ER PT J AU BRAND, HR DEISSLER, RJ AHLERS, G AF BRAND, HR DEISSLER, RJ AHLERS, G TI SIMPLE-MODEL FOR THE BENARD INSTABILITY WITH HORIZONTAL FLOW NEAR THRESHOLD SO PHYSICAL REVIEW A LA English DT Article ID CONVECTION; NOISE; INTERMITTENCY; PATTERNS; ONSET; WAVES AB We present a simple model for Rayleigh-Benard convection with an imposed horizontal flow of Reynolds number R in a container of finite width and near threshold. The model consists of two coupled envelope equations representing longitudinal and transverse traveling convection rolls. Each equation is for a wave traveling in the direction of the imposed flow. For small R, transverse rolls are stable at the convective onset. For R > R*, longitudinal rolls bifurcate from the conduction state. For a range of cross-coupling strengths and for R > R *, we obtain a transition from longitudinal to transverse rolls as the Rayleigh number is increased. This transition occurs via states for which part of the system is occupied by longitudinal, and another by transverse rolls. The behavior is strongly influenced by the presence of noise since the system first becomes convectively unstable, and therefore noise-sustained structures can play an important role. We also show that for a range of parameters in the model, a mixed state (for which both envelopes assume a nonzero value at the same location) is possible over part of the cell in a finite geometry. C1 UNIV CALIF LOS ALAMOS SCI LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. UNIV CALIF SANTA BARBARA,DEPT PHYS,SANTA BARBARA,CA 93106. UNIV CALIF SANTA BARBARA,CTR NONLINEAR STUDIES,SANTA BARBARA,CA 93106. RP BRAND, HR (reprint author), UNIV ESSEN GESAMTHSCH,FACHBEREICH PHYS 7,W-4300 ESSEN 1,GERMANY. NR 48 TC 36 Z9 42 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR 15 PY 1991 VL 43 IS 8 BP 4262 EP 4268 DI 10.1103/PhysRevA.43.4262 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FH612 UT WOS:A1991FH61200021 ER PT J AU DEISSLER, RJ ORON, A LEE, YC AF DEISSLER, RJ ORON, A LEE, YC TI EVOLUTION OF 2-DIMENSIONAL WAVES IN EXTERNALLY PERTURBED FLOW ON A VERTICAL CYLINDER SO PHYSICAL REVIEW A LA English DT Note ID LIQUID-FILM; EQUATION; NOISE; INTERMITTENCY; INSTABILITY; BREAKING; SYSTEM AB We numerically investigate in a laboratory frame the evolution of waves on the surface of fluid flowing down a cylinder in the context of a two-dimensional Kuramoto-Sivashinsky equation. The conditions for convective instability of the system are derived. We show that spiral waves emerge when the flow is driven at the inlet with a combination of spiral driving and random noise. In the case of a purely-noise-driven flow, spiral-like structures appear occasionally as short transients while the main pattern is a straight wave. In most cases the flow tends to be irregular. C1 UNIV CALIF LOS ALAMOS SCI LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,LOS ALAMOS,NM 87545. UNIV MARYLAND,DEPT PHYS & ASTRON,COLLEGE PK,MD 20740. UNIV MARYLAND,INST ADV COMP STUDIES,COLLEGE PK,MD 20740. NR 22 TC 23 Z9 23 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR 15 PY 1991 VL 43 IS 8 BP 4558 EP 4561 DI 10.1103/PhysRevA.43.4558 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA FH612 UT WOS:A1991FH61200062 ER PT J AU GRUBEL, G AXE, JD GIBBS, D LANDER, GH MARMEGGI, JC BRUCKEL, T AF GRUBEL, G AXE, JD GIBBS, D LANDER, GH MARMEGGI, JC BRUCKEL, T TI INCOMMENSURATE CHARGE-DENSITY-WAVE STATE IN ALPHA-URANIUM - A HIGH-RESOLUTION X-RAY AND NEUTRON-SCATTERING STUDY SO PHYSICAL REVIEW B LA English DT Article ID PHASE-TRANSITIONS; LOW-TEMPERATURE; HOLMIUM AB The incommensurate charge-density-wave state, which develops in alpha-uranium below 47 K, was studied in high-resolution x-ray and neutron-scattering experiments. Lock-in transitions of the incommensurate modulation wave vector were observed at 38 K (q(x) = 1/2) and 22 K (q(y) = 1/6, q(z) = 2/11) and explained in terms of a Landau theory. The simultaneous lock-in transformation of both the q(y) and q(z) components is accompanied by the formation of a phase-discommensuration lattice along the z axis. C1 COMMISS EUROPEAN COMMUNITIES,JOINT RES CTR,INST TRANSURANIUM ELEMENTS,W-7500 KARLSRUHE,GERMANY. UNIV J FOURIER,CNRS,CRISTALLOG LAB,F-38042 GRENOBLE,FRANCE. INST MAX VON LAUE PAUL LANGEVIN,F-38042 GRENOBLE,FRANCE. RP GRUBEL, G (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. RI Bruckel, Thomas/J-2968-2013 OI Bruckel, Thomas/0000-0003-1378-0416 NR 15 TC 13 Z9 13 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 8803 EP 8807 DI 10.1103/PhysRevB.43.8803 PG 5 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100001 ER PT J AU SCHMITZ, PJ LEUNG, WY KANG, HC THIEL, PA AF SCHMITZ, PJ LEUNG, WY KANG, HC THIEL, PA TI RECONSTRUCTIONS OF AU FILMS ON PD(110) SO PHYSICAL REVIEW B LA English DT Article ID ENERGY-ION-SCATTERING; AU(110) SURFACE; PT(110)-(1X2) SURFACE; 110 SURFACE; ELECTRON-DIFFRACTION; LEED; 1X2; STABILITY; LAYERS AB We present a study of thermally activated changes in Au films, 1-10 monolayers thick, on Pd(110). The films are stable against bulk dissolution until approximately 500 K, based upon Auger electron spectroscopy. For Au coverages below 1.5 monolayers, only a (1 x 1) overlayer structure is observed with low-energy electron diffraction over the entire temperature range studied (130-800 K). At coverages above 1.0 monolayers and after annealing to temperatures above 300 K, a (1 x z) diffraction pattern develops. With increasing coverage the value of z increases continuously from 2 to 3, reaching z = 3 at 4 monolayers. We propose that the diffraction pattern reflects a coverage-dependent mixture of small domains of (1 x 2) and (1 x 3) reconstruction, with the (1 x 2) favored at low coverage and the (1 x 3) favored at high coverage. This model is rationalized in terms of the film's coverage-dependent morphology, which can be described as Stranski-Krastanov with a critical thickness of 2 monolayers. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. RI Kang, Hway Chuan/A-3401-2012 NR 42 TC 13 Z9 13 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 8834 EP 8840 DI 10.1103/PhysRevB.43.8834 PG 7 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100005 ER PT J AU TSANG, T SRINIVASANRAO, T FISCHER, J AF TSANG, T SRINIVASANRAO, T FISCHER, J TI SURFACE-PLASMON FIELD-ENHANCED MULTIPHOTON PHOTOELECTRIC-EMISSION FROM METAL-FILMS SO PHYSICAL REVIEW B LA English DT Article ID PICOSECOND LASER-PULSES; SILVER FILMS; 2-PHOTON PHOTOEMISSION; 2ND-HARMONIC GENERATION; BRILLOUIN-SCATTERING; OPTICAL-CONSTANTS; TUNNEL-JUNCTIONS; THIN-FILMS; EXCITATION; FEMTOSECOND AB We report a study of surface-plasmon-mediated multiphoton photoelectric emission from thin films of Ag, Au, Cu, and Al. The experiments were performed in the Kretchmann attenuated-total-internal reflection geometry while the excitation source was an unamplified femtosecond colliding-pulse mode-locked ring laser. Contrast to the electron emission obtained by irradiating the laser on a metal surface, electron yield increases by several orders of magnitude with fairly high quantum efficiency, is observed when photons are coupled to the surface-plasmon modes of these films. Although the photon absorption reaches its maximum when the reflectivity exhibits a deep minimum at the surface-plasmon resonance angle, it is found that the maximum electron yield occurs at a slightly different angle than the reflectivity dip. The results of these measurements favor the field-density calculations using the Fresnel equations. The width of the electron temporal profile, measured utilizing this nonlinear photoelectric effect, however, fails to show the narrowing commensurate with the higher-order nonlinearity. RP BROOKHAVEN NATL LAB, UPTON, NY 11973 USA. NR 39 TC 71 Z9 71 U1 4 U2 18 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 8870 EP 8878 DI 10.1103/PhysRevB.43.8870 PG 9 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100009 ER PT J AU DANDREA, RG ZUNGER, A AF DANDREA, RG ZUNGER, A TI 1ST-PRINCIPLES STUDY OF INTERVALLEY MIXING - ULTRATHIN GAAS-GAP SUPERLATTICES SO PHYSICAL REVIEW B LA English DT Article ID LAYER SUPER-LATTICES; VAPOR-PHASE EPITAXY; ALAS SUPERLATTICES; ELECTRONIC-PROPERTIES; OPTICAL-PROPERTIES; BAND-GAPS; DEFORMATION POTENTIALS; BRILLOUIN-ZONE; SPECIAL POINTS; SEMICONDUCTOR AB First-principles pseudopotential calculations are reported for the structural properties, band offsets, and single-particle electronic states of (GaP)n(GaAs)n (001) and (111) superlattices with n less-than-or-equal-to 3. With the aim of developing a systematic theory to relate superlattice levels in these ultrathin systems to those of their constituents, the superlattice is treated as evolving from a virtual-crystal parent zinc-blende compound. A semiquantitative description of the resulting superlattice states evolves from this theory, which is based on (i) the small perturbative nature of the superlattice ordering potential with respect to this parent compound, (ii) a generic n dependence found for the intervalley coupling strengths, (iii) generic selection rules governing intervalley mixing, and (iv) observations of the dependence of coupling strengths on the anion versus cation character of the involved states. Application of these principles to (110) and (201) GaAs/GaP, and to the previously studied GaAs/A1As systems, demonstrates their usefulness. Calculated energy gaps (and their direct versus indirect and type-I versus type-II character) are presented for the superlattices studied. RP DANDREA, RG (reprint author), SOLAR ENERGY RES INST,GOLDEN,CO 80401, USA. RI Zunger, Alex/A-6733-2013 NR 78 TC 35 Z9 36 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 8962 EP 8989 DI 10.1103/PhysRevB.43.8962 PG 28 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100020 ER PT J AU HOLROYD, RA GEER, S PTOHOS, F AF HOLROYD, RA GEER, S PTOHOS, F TI FREE-ION YIELDS FOR SEVERAL SILICON-CONTAINING, GERMANIUM-CONTAINING, AND TIN-CONTAINING LIQUIDS AND THEIR MIXTURES SO PHYSICAL REVIEW B LA English DT Article ID EXCESS ELECTRON-MOBILITY; NORMAL-HEXANE; HIGH-PRESSURE; HYDROCARBONS; TETRAMETHYLSILANE; RANGES AB Free-ion yields have been measured as a function of applied electric field for several room-temperature liquids containing silicon, germanium, or tin atoms. The results show that tetra-alkyl compounds of the same molecular structure have similar free-ion yields independent of the nature of the central group-IV atom. Tetramethylsilane, tetramethylgermane, and tetramethylstannane have similar field-dependent yields. Similarly, tetraethylsilane and tetraethylstannane have comparable yields; the same is true for tetrabutylgermane and tetrabutylstannane. The yields do depend on the nature of the attached alkyl groups: the tetramethyl liquids have higher yields than the tetraethyl liquids, which in turn have higher yields than the tetrabutyl liquids. Fitting the field-dependent free-ion yields to extract a measure of the average thermalization ranges of electrons liberated in the liquids by the ionization process we find that within the precision of our measurements the products of the average electron range times the dielectric constant of the liquid are identical for tetra-alkyl liquids with similar molecular structures. The field-dependent free-ion yields for binary mixtures of high-yield liquid hydrocarbons have also been measured. The yields in these mixtures tend to be less than the yields in either of the pure components. This suggests shorter electron thermalization lengths in mixtures than in pure liquids. C1 HARVARD UNIV,HIGH ENERGY PHYS LAB,CAMBRIDGE,MA 02138. RP HOLROYD, RA (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. NR 29 TC 18 Z9 18 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 9003 EP 9011 DI 10.1103/PhysRevB.43.9003 PG 9 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100022 ER PT J AU SURH, MP LOUIE, SG COHEN, ML AF SURH, MP LOUIE, SG COHEN, ML TI QUASI-PARTICLE ENERGIES FOR CUBIC BN, BP, AND BAS SO PHYSICAL REVIEW B LA English DT Article ID DENSITY-FUNCTIONAL THEORY; BORON-NITRIDE; ELECTRONIC-STRUCTURE; BAND-STRUCTURE; SEMICONDUCTORS; PHOTOEMISSION; INSULATORS; DIAMOND; GAP; DISCONTINUITIES AB Electronic excitation energies at the high-symmetry points GAMMA, X, and L are obtained for zinc-blende-structure BN, BP, and BAs in the GW approximation using a model dielectric function. A model for the static screening matrix makes use of the ab initio ground-state charge density and either experimental values or empirical estimates for epsilon-infinity, the electronic contribution to the macroscopic dielectric constant. Wave functions from an ab initio local-density-approximation calculation with norm-conserving pseudopotentials are employed along with the self-consistent quasiparticle spectrum to obtain the energy-dependent one-particle Green function G. The minimum band gaps are found to be 6.3, 1.9, and 1.6 eV for BN, BP, and BAs, respectively, in close agreement with existing measurements of 6.1 and 2.0 eV for BN and BP, respectively. The BN direct band gap is predicted to be 11.4 eV versus the experimental value of 14.5 eV, and the BP direct band gap is predicted to be 4.4 eV versus 5.0 eV from experiment. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB, DIV MAT SCI, BERKELEY, CA 94720 USA. RP SURH, MP (reprint author), UNIV CALIF BERKELEY, DEPT PHYS, BERKELEY, CA 94720 USA. NR 57 TC 117 Z9 119 U1 3 U2 17 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 9126 EP 9132 DI 10.1103/PhysRevB.43.9126 PG 7 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100036 ER PT J AU PETTERSSON, S AF PETTERSSON, S TI SOLVING THE PHONON BOLTZMANN-EQUATION WITH THE VARIATIONAL METHOD SO PHYSICAL REVIEW B LA English DT Article ID THERMAL-CONDUCTIVITY; HEAT-CAPACITY; ALKALI-HALIDES; PRESSURE; CRYSTALS; CAF2 AB The thermal conductivity of 17 alkali halides with the NaCl structure has been calculated. The deformation-dipole model has been used to calculate realistic phonon dispersion relations, which are used to solve the Boltzmann equation with the variational method. Many different trial functions and linear combinations have been used and the resultant approximate solutions are discussed. Assuming different trial functions for different branches increases the calculated thermal conductivity by 10-150%. The error estimates suggest that the true solution to the Boltzmann equation would increase the calculated thermal conductivity by another 100%. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. NR 30 TC 12 Z9 12 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 9238 EP 9246 DI 10.1103/PhysRevB.43.9238 PG 9 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100048 ER PT J AU CORKILL, JL GARCIA, A COHEN, ML AF CORKILL, JL GARCIA, A COHEN, ML TI THEORETICAL-STUDY OF HIGH-PRESSURE PHASES OF TIN SO PHYSICAL REVIEW B LA English DT Note ID STRUCTURAL-PROPERTIES; TRANSITIONS; ENERGY; STATE; SI; GE AB High-pressure phases of Sn are investigated with use of the first-principles pseudopotential total-energy method. The T = 0 calculations accurately reproduce the structural parameters of the low-pressure modifications alpha-Sn and beta-Sn and predict a transition to either bcc or bct at high pressure. The calculated compression ratio of the body-centered phase at high pressure also agrees well with experiment. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP CORKILL, JL (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Garcia, Alberto/A-7460-2008 OI Garcia, Alberto/0000-0001-5138-9579 NR 25 TC 20 Z9 21 U1 2 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 9251 EP 9254 DI 10.1103/PhysRevB.43.9251 PG 4 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100050 ER PT J AU DAVIS, BM SEIDMAN, DN MOREAU, A KETTERSON, JB MATTSON, J GRIMSDITCH, M AF DAVIS, BM SEIDMAN, DN MOREAU, A KETTERSON, JB MATTSON, J GRIMSDITCH, M TI SUPERMODULUS EFFECT IN CU/PD AND CU/NI SUPERLATTICES SO PHYSICAL REVIEW B LA English DT Note ID EMBEDDED-ATOM-METHOD; MODULATED CU-NI; ELASTIC-CONSTANTS; THIN-FILMS; FOILS; MODULUS; ALLOYS; EVAPORATOR; PALLADIUM; NICKEL AB The elastic and structural properties of Cu/Pd and Cu/Ni superlattices have been determined. Microstructurally the films have the same growth mechanisms, growth textures, and composition modulation amplitudes, as in past studies where the "supermodulus effect" was reported. Advanced techniques have been used to measure the flexural, shear, and Young's moduli of the thin films, and no significant anomalous elastic behavior has been observed. C1 NORTHWESTERN UNIV,MAT RES CTR,EVANSTON,IL 60208. NORTHWESTERN UNIV,DEPT PHYS & ASTRON,EVANSTON,IL 60208. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP DAVIS, BM (reprint author), NORTHWESTERN UNIV,DEPT MAT SCI & ENGN,EVANSTON,IL 60208, USA. RI Seidman, David/B-6697-2009; Ketterson, John/B-7234-2009 NR 30 TC 50 Z9 50 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 9304 EP 9307 DI 10.1103/PhysRevB.43.9304 PG 4 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100067 ER PT J AU RUDBERG, BGR JONSON, M AF RUDBERG, BGR JONSON, M TI TUNNELING IN A SELF-CONSISTENT DYNAMIC IMAGE POTENTIAL SO PHYSICAL REVIEW B LA English DT Note ID TRAVERSAL TIME; BARRIERS AB We have calculated the self-consistent effective potential for an electron tunneling through a square barrier while interacting with surface plasmons. This potential reduces to the classical image potential in the static limit. In the opposite limit, when the "velocity" of the tunneling electron is large, it reduces to the unperturbed square-barrier potential. For a wide variety of parameters the dynamic effects on the transmission coefficient T = (t2) can, for instance, be related to the Buttiker-Landauer traversal time for tunneling, given by tau-BL = h(d lnt/dV). C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. RP RUDBERG, BGR (reprint author), CHALMERS UNIV TECHNOL,INST THEORET PHYS,S-41296 GOTHENBURG,SWEDEN. RI Jonson, Mats/D-6545-2011 NR 14 TC 9 Z9 9 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 11 BP 9358 EP 9361 DI 10.1103/PhysRevB.43.9358 PG 4 WC Physics, Condensed Matter SC Physics GA FH291 UT WOS:A1991FH29100081 ER PT J AU CHRZAN, DC FALICOV, LM MACLAREN, JM ZHANG, XG GONIS, A AF CHRZAN, DC FALICOV, LM MACLAREN, JM ZHANG, XG GONIS, A TI ELECTRONIC AND MAGNETIC-STRUCTURE OF (111) STACKING-FAULTS IN NICKEL SO PHYSICAL REVIEW B LA English DT Article ID ENERGY; FILMS; FERROMAGNETISM; PHOTOEMISSION; OVERLAYERS; INTERFACES; SURFACES; NI AB The electronic and magnetic structure of {111} stacking faults in nickel is investigated utilizing a fully self-consistent, layered multiple-scattering approach which does not require full three-dimensional symmetry or the use of finite-size slabs. The electronic and magnetic structures of a twin boundary, an intrinsic fault, an extrinsic fault, and two other stacking sequences are calculated. In addition, total energies of the faults are calculated and found to be in good agreement with the available experimental results. Localized states appear in all the studied stacking faults; the state's energies and exchange splittings are tabulated. The presence of a stacking fault results in a decrease in the spin polarization near the faults. This decrease arises from subtle changes in the electronic structure arising from the fault. For all the faults, the spin polarization is found to be insensitive to the orientation of the nearest-neighbor atoms, but instead can be related to the distance to the nearest atom in the direction perpendicular to the fault plane. Very simple empirical expressions for calculating the total energy and spin polarization of any stacking configuration are presented. C1 TULANE UNIV,DEPT PHYS,NEW ORLEANS,LA 70118. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. UNIV CALIF LAWRENCE LIVERMORE NATL LAB,CHEM & MAT SCI,LIVERMORE,CA 94550. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DEPT PHYS,BERKELEY,CA 94720. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,FAC CHEM SCI,BERKELEY,CA 94720. RP CHRZAN, DC (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. NR 28 TC 9 Z9 9 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 12 BP 9442 EP 9451 DI 10.1103/PhysRevB.43.9442 PG 10 WC Physics, Condensed Matter SC Physics GA FK191 UT WOS:A1991FK19100006 ER PT J AU FEIBELMAN, PJ AF FEIBELMAN, PJ TI 1ST-PRINCIPLES CALCULATIONS OF ADATOM BINDING AND INTERACTION ON RH(001) SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE CALCULATIONS; ANHARMONIC VIBRATIONAL-MODES; ADSORBED CHALCOGEN; LINEAR COMBINATION; EFFICIENT SOLUTION; SURFACE-DIFFUSION; POISSON EQUATION; CHEMISORBED H; AL ATOMS; CRYSTAL AB The self-consistent scattering-theory approach to adsorption energetics is applied to light atoms, H and S, on a transition-metal surface, Rh(001). A single H adatom is predicted to bind in a four-fold hollow at a height of 1.23 bohr above the outer Rh layer, with a symmetric stretch frequency of 98 meV in the harmonic approximation. A single S atom binds in a fourfold hollow at a height of 2.77 bohr above the surface, indicative of covalent adsorption. Two H atoms fixed at their isolated-adatom equilibrium positions on Rh(001), but in neighboring fourfold hollows, are well screened from each other and hardly interact at all. Under the same conditions, a H and a S adatom are subject to a repulsion of 0.17 eV. RP FEIBELMAN, PJ (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 41 TC 38 Z9 38 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 12 BP 9452 EP 9458 DI 10.1103/PhysRevB.43.9452 PG 7 WC Physics, Condensed Matter SC Physics GA FK191 UT WOS:A1991FK19100007 ER PT J AU HAO, YG ERIKSSON, O FERNANDO, GW COOPER, BR AF HAO, YG ERIKSSON, O FERNANDO, GW COOPER, BR TI ELECTRONIC-STRUCTURE OF THE (111) AND (100) SURFACES OF DELTA-PU SO PHYSICAL REVIEW B LA English DT Article ID TIN-ORBITAL CALCULATION; ACTINIDE METALS; TRANSITION-METALS; ENERGIES AB An all-electron self-consistent surface-electronic-structure calculations of an actinide system has been performed using the film-linearized muffin-tin-orbital method. The calculations have been performed using both (100)- and (111)-oriented five-layer plutonium slab geometries. Our calculated work functions for the system are 3.68 and 4.14 eV for the (100) and (111) surfaces, respectively, with the 6p electrons treated as core states. The calculations include the spin-orbit coupling, and the calculated work functions are in good agreement with experimental values of 3.4-3.9 eV for uranium. The narrow bandwidth of the 5f electrons and the position relative to the s and d bands relate to the intermediate delocalization of the 5f electrons and the existence of hybridization with the s and d electrons. C1 UNIV CALIF LOS ALAMOS SCI LAB,CTR MAT SCI,LOS ALAMOS,NM 87545. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP HAO, YG (reprint author), W VIRGINIA UNIV,DEPT PHYS,MORGANTOWN,WV 26506, USA. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 31 TC 33 Z9 34 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 12 BP 9467 EP 9474 DI 10.1103/PhysRevB.43.9467 PG 8 WC Physics, Condensed Matter SC Physics GA FK191 UT WOS:A1991FK19100009 ER PT J AU MYERS, SM RICHARDS, PM FOLLSTAEDT, DM SCHIRBER, JE AF MYERS, SM RICHARDS, PM FOLLSTAEDT, DM SCHIRBER, JE TI SUPERSTOICHIOMETRY, ACCELERATED DIFFUSION, AND NUCLEAR-REACTIONS IN DEUTERIUM-IMPLANTED PALLADIUM SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-DYNAMICS; CROSS-SECTIONS; HYDROGEN; FUSION; METAL; HYDRIDES AB Deuterium (D) was introduced into Pd at atomic ratios greater than one by ion implantation at cryogenic temperatures. The rise and saturation of the D concentration at these low temperatures, together with the decay of the superstoichiometric state during annealing, were observed by detecting charged particles from the nuclear reaction D(d,p)T when a deuteron beam impinged on the specimen. At implantation temperatures of 41 and 81 K, a saturation concentration ratio [D]/[Pd] of 1.6 +/- 0.2 was reached, substantially above the limit of 1.0 observed in gas-phase charging. As the temperature was subsequently ramped upward, [D]/[Pd] abruptly decreased to approximately 1.0 near 120 K, reflecting a process of accelerated transport unique to the superstoichiometric state. The responsible diffusion mechanism was theoretically examined using analytical modeling and molecular-dynamics simulations, leading to a picture of correlated D hopping among octahedral and tetrahedral interstitial sites. Cold fusion was not detected in the absence of external ion bombardment, implying an upper bound on the reaction rate in the high-concentration deuteride of approximately 10(-21) events/s D atom. RP MYERS, SM (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 24 TC 21 Z9 21 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 12 BP 9503 EP 9510 DI 10.1103/PhysRevB.43.9503 PG 8 WC Physics, Condensed Matter SC Physics GA FK191 UT WOS:A1991FK19100014 ER PT J AU ROZING, GJ MIJNARENDS, PE KOELLING, DD AF ROZING, GJ MIJNARENDS, PE KOELLING, DD TI PROBING THE F-ELECTRONS IN URU2SI2 WITH POSITRONS - A THEORETICAL INVESTIGATION SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTOR URU2SI2; FERMI-SURFACE; ANNIHILATION; SYSTEMS AB The two-photon momentum distribution for positron annihilation is computed for the heavy-fermion system URu2Si2. A nonrelativistic approximation of the positron-electron overlap integrals is applied to wave functions obtained from a fully relativistic, self-consistent band-structure calculation. The crystal structure causes a preference of the positron for the uranium site, resulting in a considerable contribution to the two-photon momentum distribution of the f-electron states and marked structure related to the Fermi surface. Results are presented for integration of the two-photon momentum distribution along the [001] and [101] directions. Subsequent application of the Lock-Crisp-West theorem reveals Fermi-surface effects superimposed on long-wavelength structure due to the inhomogeneity of the positron wave function. It is concluded that positron annihilation can be used to study the nature of the f electrons in this heavy-fermion system. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP ROZING, GJ (reprint author), NETHERLANDS ENERGY RES FDN,1755 ZG PETTEN,NETHERLANDS. NR 26 TC 15 Z9 15 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 12 BP 9515 EP 9522 DI 10.1103/PhysRevB.43.9515 PG 8 WC Physics, Condensed Matter SC Physics GA FK191 UT WOS:A1991FK19100016 ER PT J AU STIFFLER, SR THOMPSON, MO PEERCY, PS AF STIFFLER, SR THOMPSON, MO PEERCY, PS TI TRANSIENT NUCLEATION FOLLOWING PULSED-LASER MELTING OF THIN SILICON FILMS SO PHYSICAL REVIEW B LA English DT Article AB Thin Si films on thermally grown SiO2 layers were completely melted by pulsed-laser irradiation. The molten films cool very rapidly (> 10(9) K/s) until bulk nucleation initiates solidification. The quench rate was varied by changing the thickness of the Si or the SiO2 layers. For quenches below approximately 10(10) K/s the supercooling prior to nucleation was constant and approximately 500 K; however, for more rapid quenches, the supercooling increases significantly. This increase is attributed to embryo distributions that fall out of steady state during rapid quenches. C1 CORNELL UNIV,DEPT MAT SCI & ENGN,ITHACA,NY 14853. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. OI Thompson, Michael/0000-0002-4933-009X NR 18 TC 81 Z9 81 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 12 BP 9851 EP 9855 DI 10.1103/PhysRevB.43.9851 PG 5 WC Physics, Condensed Matter SC Physics GA FK191 UT WOS:A1991FK19100055 ER PT J AU ZHANG, SB COHEN, ML LOUIE, SG AF ZHANG, SB COHEN, ML LOUIE, SG TI CHEMICAL-SHIFT AND ZONE-FOLDING EFFECTS ON THE ENERGY GAPS OF GAAS-ALAS (001) SUPERLATTICES SO PHYSICAL REVIEW B LA English DT Note ID PERIOD GAAS/ALAS SUPERLATTICES; INTERBAND-TRANSITIONS; OPTICAL-PROPERTIES; BAND-STRUCTURE AB The chemical shift and zone-folding effects obtained from quasiparticle calculations for ultrathin GaAs-AlAs superlattices are incorporated within a Kronig-Penny model for superlattices of the arbitrary lattice period. We determine that superlattices with lattice periods in the range of 3 x 3 to 9 x 9 have an X-derived pseudodirect gap. This result explains both the results from first-principles calculations for ultrathin superlattices and those from experiments for a broader lattice period. C1 UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. XEROX CORP,PALO ALTO RES CTR,PALO ALTO,CA 94304. RP ZHANG, SB (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Krausnick, Jennifer/D-6291-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 19 TC 9 Z9 9 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 1991 VL 43 IS 12 BP 9951 EP 9954 DI 10.1103/PhysRevB.43.9951 PG 4 WC Physics, Condensed Matter SC Physics GA FK191 UT WOS:A1991FK19100070 ER PT J AU BUTLER, MN MALANEY, RA MIJIC, MB AF BUTLER, MN MALANEY, RA MIJIC, MB TI EVOLUTION OF A SUPERCONDUCTING-COSMIC-STRING NETWORK SO PHYSICAL REVIEW D LA English DT Article AB It has normally been assumed that the evolution of a cosmic-string network is independent of whether or not the strings are superconducting. We show here, in a simple model, how the evolution of a superconducting-cosmic-string network may be altered, principally by the enhanced radiation losses. We analyze the evolution of the network as a function of the loop self-intersection probability, and find that a scaling solution may be possible for smaller loop self-intersection probabilities than allowed for normal strings. A possible consequence of this is a significant modification of the loop number density. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550. UNIV BRITISH COLUMBIA,DEPT PHYS,VANCOUVER V6T 2A6,BC,CANADA. RP BUTLER, MN (reprint author), TRIUMF,4004 WESBROOK MALL,VANCOUVER V6T 2A3,BC,CANADA. RI Malaney, Robert/F-6588-2012 OI Malaney, Robert/0000-0001-9672-5601 NR 13 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 15 PY 1991 VL 43 IS 8 BP 2535 EP 2541 DI 10.1103/PhysRevD.43.2535 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FH288 UT WOS:A1991FH28800011 ER PT J AU BENNETT, DP BOUCHET, FR AF BENNETT, DP BOUCHET, FR TI CONSTRAINTS ON THE GRAVITY-WAVE BACKGROUND GENERATED BY COSMIC STRINGS SO PHYSICAL REVIEW D LA English DT Note ID GRAVITATIONAL-RADIATION; EVOLUTION; NUCLEOSYNTHESIS; NETWORKS AB We investigate the limits that can be placed on a cosmic-string-generated stochastic gravity-wave background by timing of the millisecond pulsar and by primordial nucleosynthesis. These limits on the gravity-wave background are used to generate limits on the mass per unit length of the cosmic string, mu. The limit due to the millisecond-pulsar constraint is mu < 4 x 10(-5)c2/G while the nucleosynthesis limit ranges from mu < 6 x 10(-6)c2/G to mu < 2 x 10(-5)c2/G depending on the history of the Universe at temperatures above 1 TeV and the details of the QCD phase transition. These limits are significantly weaker than the best limit obtained from observations of the microwave background (mu < 5 x 10(-6)c2/G) and are well above the value of mu that seems to be favored by the string-seeded galaxy-formation scenario. C1 UNIV CALIF BERKELEY,CTR PARTICLE ASTROPHYS,BERKELEY,CA 94720. INST ASTROPHYS,F-75014 PARIS,FRANCE. ECOLE POLYTECH,CTR PHYS THEOR,F-91128 PALAISEAU,FRANCE. RP BENNETT, DP (reprint author), UNIV CALIF LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550, USA. RI Bouchet, Francois/B-5202-2014 NR 34 TC 26 Z9 26 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 15 PY 1991 VL 43 IS 8 BP 2733 EP 2735 DI 10.1103/PhysRevD.43.2733 PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA FH288 UT WOS:A1991FH28800034 ER PT J AU YEN, YF BRINKMOLLER, B DEHNHARD, D STERBENZ, SM YU, YJ BERMAN, B BURLESON, GR CRANSTON, K KLEIN, A KYLE, GS ALARCON, R AVERETT, T COMFORT, JR GORGEN, JJ RITCHIE, BG TINSLEY, JR BARLETT, M HOFFMANN, GW JOHNSON, K MOORE, CF PURCELL, M WARD, H WILLIAMS, A FAUCETT, JA GREENE, SJ JARMER, JJ MCGILL, JA MORRIS, CL PENTTILA, S TANAKA, N FORTUNE, HT INSKO, E IVIE, R ODONNELL, JM SMITH, D KHANDAKER, MA CHAKRAVARTI, S AF YEN, YF BRINKMOLLER, B DEHNHARD, D STERBENZ, SM YU, YJ BERMAN, B BURLESON, GR CRANSTON, K KLEIN, A KYLE, GS ALARCON, R AVERETT, T COMFORT, JR GORGEN, JJ RITCHIE, BG TINSLEY, JR BARLETT, M HOFFMANN, GW JOHNSON, K MOORE, CF PURCELL, M WARD, H WILLIAMS, A FAUCETT, JA GREENE, SJ JARMER, JJ MCGILL, JA MORRIS, CL PENTTILA, S TANAKA, N FORTUNE, HT INSKO, E IVIE, R ODONNELL, JM SMITH, D KHANDAKER, MA CHAKRAVARTI, S TI ASYMMETRY MEASUREMENT OF PION ELASTIC-SCATTERING FROM POLARIZED C-13 IN THE ENERGY REGION OF THE P-33 RESONANCE SO PHYSICAL REVIEW LETTERS LA English DT Article ID NUCLEON AB Analyzing powers A(y) were measured for pi+ and pi- elastic scattering from polarized C-13 at energies near the P-33 resonance. At T-pi = 132 MeV the values of A(y) are significantly different from zero for pi-. For pi+ at 132 MeV and for both pi- and pi+ at all other energies, the A(y) are mostly consistent with zero. These data differ from the predictions of present pion-nucleus reaction theories, especially at large momentum transfers. C1 NEW MEXICO STATE UNIV,LAS CRUCES,NM 88003. ARIZONA STATE UNIV,TEMPE,AZ 85287. UNIV TEXAS,AUSTIN,TX 78712. UNIV CALIF LOS ALAMOS SCI LAB,LOS ALAMOS,NM 87545. UNIV PENN,PHILADELPHIA,PA 19104. UNIV MARYLAND,COLLEGE PK,MD 20742. CALIF STATE POLYTECH UNIV POMONA,POMONA,CA 91768. RP YEN, YF (reprint author), UNIV MINNESOTA,MINNEAPOLIS,MN 55455, USA. RI Averett, Todd/A-2969-2011 NR 23 TC 24 Z9 24 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 15 PY 1991 VL 66 IS 15 BP 1959 EP 1962 DI 10.1103/PhysRevLett.66.1959 PG 4 WC Physics, Multidisciplinary SC Physics GA FG033 UT WOS:A1991FG03300004 ER PT J AU DUBOIS, DF ROSE, HA RUSSELL, D AF DUBOIS, DF ROSE, HA RUSSELL, D TI COEXISTENCE OF PARAMETRIC DECAY CASCADES AND CAVITON COLLAPSE AT SUBCRITICAL DENSITIES SO PHYSICAL REVIEW LETTERS LA English DT Article ID STRONG LANGMUIR TURBULENCE; IONOSPHERIC MODIFICATION; INSTABILITIES; PLASMA; EVOLUTION; SPECTRA; WAVES AB We report results of two-dimensional numerical solutions of Zakharov's model for strong Langmuir turbulence excited by powerful electromagnetic pump waves at subcritical densities, as in hf modification of the ionosphere and laser-plasma interactions. The results show that truncated parametric decay cascades can coexist with caviton collapse for moderate pump power. A high level of ion density fluctuations, driven primarily by caviton collapse, produces energy and power spectra which are not consistent with conventional weak turbulence theory. C1 LODESTAR RES CORP,BOULDER,CO 80301. RP DUBOIS, DF (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,MS B262,LOS ALAMOS,NM 87545, USA. NR 22 TC 60 Z9 60 U1 1 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 APR 15 PY 1991 VL 66 IS 15 BP 1970 EP 1973 DI 10.1103/PhysRevLett.66.1970 PG 4 WC Physics, Multidisciplinary SC Physics GA FG033 UT WOS:A1991FG03300007 ER PT J AU HANADA, K TANAKA, H IIDA, M IDE, S MINAMI, T NAKAMURA, M MAEKAWA, T TERUMICHI, Y TANAKA, S YAMADA, M MANICKAM, J WHITE, RB AF HANADA, K TANAKA, H IIDA, M IDE, S MINAMI, T NAKAMURA, M MAEKAWA, T TERUMICHI, Y TANAKA, S YAMADA, M MANICKAM, J WHITE, RB TI SAWTOOTH STABILIZATION BY LOCALIZED ELECTRON-CYCLOTRON HEATING IN A TOKAMAK PLASMA SO PHYSICAL REVIEW LETTERS LA English DT Article ID HYBRID CURRENT DRIVE; ENERGETIC TRAPPED-PARTICLES; ASDEX TOKAMAK; WT-3 TOKAMAK; SAWTEETH; OSCILLATIONS; SUPPRESSION AB Sawtooth oscillations (STO) in the Ohmically heated WT-3 tokamak are strongly modified or suppressed by localized electron-cyclotron-resonance heating (ECH) near the q = 1 surface, where q refers to the safety factor. The effect of ECH is much stronger when it is applied on the high-field side as compared to the low-field side. Complete suppression of STO is achieved for the duration of the ECH, in most cases, when it is applied on the high-field side of a low-density plasma, provided the ECH power exceeds a threshold value. STO stabilization is attributed to a modification of the current-density profile by hot electrons generated by ECH, which reduces the shear in the q = 1 region. C1 PRINCETON UNIV,PLASMA PHYS LAB,PRINCETON,NJ 08543. RP HANADA, K (reprint author), KYOTO UNIV,FAC SCI,DEPT PHYS,KYOTO 606,JAPAN. RI White, Roscoe/D-1773-2013 OI White, Roscoe/0000-0002-4239-2685 NR 16 TC 27 Z9 28 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 15 PY 1991 VL 66 IS 15 BP 1974 EP 1977 DI 10.1103/PhysRevLett.66.1974 PG 4 WC Physics, Multidisciplinary SC Physics GA FG033 UT WOS:A1991FG03300008 ER PT J AU YE, YY CHAN, CT HO, KM AF YE, YY CHAN, CT HO, KM TI EFFECT OF PHONON ANOMALIES ON THE SHEAR RESPONSE OF MARTENSITIC CRYSTALS SO PHYSICAL REVIEW LETTERS LA English DT Article ID NEUTRON-SCATTERING; PSEUDOELASTICITY; TRANSFORMATION; ALLOYS; BEHAVIOR AB The shear response of a prototypical martensitic system is studied using a simple model incorporating the effects of both anharmonicity and anomalous phonon behavior. Using parameters determined from experimental phonon data, we show that the pseudoelastic and thermoelastic effects characteristic of Ni-Al and many other shape-memory alloys are closely related to the observed phonon anomalies. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. WUHAN UNIV,DEPT PHYS,WUHAN,PEOPLES R CHINA. RP YE, YY (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 20 TC 9 Z9 9 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 APR 15 PY 1991 VL 66 IS 15 BP 2018 EP 2021 DI 10.1103/PhysRevLett.66.2018 PG 4 WC Physics, Multidisciplinary SC Physics GA FG033 UT WOS:A1991FG03300019 ER PT J AU DELAND, SM MOZURKEWICH, G CHAPMAN, LD AF DELAND, SM MOZURKEWICH, G CHAPMAN, LD TI X-RAY-INVESTIGATION OF CHARGE-DENSITY-WAVE PINNING IN BLUE BRONZE SO PHYSICAL REVIEW LETTERS LA English DT Article ID PEIERLS TRANSITION; K0.30MOO3; DYNAMICS; IRRADIATION; RB0.30MOO3; STATE AB High-resolution x-ray diffraction has resolved the phase-coherence volume of the charge-density wave in electron-irradiated blue bronze. The coherence volume is 3.7 x 10(8) angstrom3 for defect density n = 0.034 at. %. The coherence lengths decrease roughly as n-0.4. Results are contrasted with various theories of pinning. C1 UNIV ILLINOIS,DEPT PHYS,URBANA,IL 61801. BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973. NR 24 TC 20 Z9 20 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 15 PY 1991 VL 66 IS 15 BP 2026 EP 2029 DI 10.1103/PhysRevLett.66.2026 PG 4 WC Physics, Multidisciplinary SC Physics GA FG033 UT WOS:A1991FG03300021 ER PT J AU HOLM, DD KOVACIC, G SUNDARAM, B AF HOLM, DD KOVACIC, G SUNDARAM, B TI CHAOTIC LASER MATTER INTERACTION SO PHYSICS LETTERS A LA English DT Article AB Hamiltonian Silnikov orbits are shown to be produced when a system of two-level atoms interacting via a self-consistent electric field in a single-model lossless cavity is perturbed by a small-amplitude probe laser (a weak, externally imposed, monochromatic electromagnetic field). This result is obtained by utilizing the two constants of motion which exist in the perturbed problem and by calculating a Melnikov function whose nondegenerate zeros imply transverse intersections of the stable and unstable manifolds of a hyperbolic fixed point set. The dynamics of the system on the Silnikov orbits contains a Smale horsehoe construction, leading to intermittent switching of the sign of the electric field which has extreme sensitivity to initial conditions. C1 UNIV CALIF LOS ALAMOS SCI LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP HOLM, DD (reprint author), UNIV CALIF LOS ALAMOS SCI LAB,DIV THEORET,MS B284,LOS ALAMOS,NM 87545, USA. RI Sundaram, Bala/A-6532-2010; OI Sundaram, Bala/0000-0002-1728-704X; Holm, Darryl D/0000-0001-6362-9912 NR 10 TC 18 Z9 18 U1 0 U2 1 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 APR 15 PY 1991 VL 154 IS 7-8 BP 346 EP 352 DI 10.1016/0375-9601(91)90030-C PG 7 WC Physics, Multidisciplinary SC Physics GA FH907 UT WOS:A1991FH90700006 ER PT J AU RAY, S DUTTA, J BARUA, AK DEB, SK AF RAY, S DUTTA, J BARUA, AK DEB, SK TI BILAYER SNO2-IN/SNO2 THIN-FILMS AS TRANSPARENT ELECTRODES OF AMORPHOUS-SILICON SOLAR-CELLS SO THIN SOLID FILMS LA English DT Article ID DEPOSITION PARAMETERS; PLASMA; DEGRADATION; HYDROGEN AB Bilayer films of SnO2:In/SnO2 were deposited, and the deposition parameters of these films were optimized to obtain good electrical and optical properties for application as the transparent electrode of amorphous silicon solar cells. A depth-profiling technique using secondary ion mass spectrometry was used to study the diffusion of elements. The SnO2 layer thickness was varied to check the diffusion of indium into the p and i layers, which affects the electrical properties of the amorphous layers of the solar cell. Optimization of SnO2 layer thickness allows us to raise the p-layer deposition temperature to 180-degrees-C without enhancing indium diffusion into the p-i interface. C1 SOLAR ENERGY RES INST,GOLDEN,CO 80401. RP RAY, S (reprint author), INDIAN ASSOC CULTIVAT SCI,ENERGY RES UNIT,CALCUTTA 700032,W BENGAL,INDIA. RI Dutta, Joydeep /B-4675-2011 OI Dutta, Joydeep /0000-0002-0074-3504 NR 17 TC 16 Z9 16 U1 0 U2 8 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD APR 15 PY 1991 VL 199 IS 2 BP 201 EP 207 DI 10.1016/0040-6090(91)90001-E PG 7 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA FL634 UT WOS:A1991FL63400001 ER PT J AU POTEAT, RM AF POTEAT, RM TI TECHNOLOGY-TRANSFER FROM NATIONAL LABORATORIES IN THE 90S - A PARTNERSHIP WITH INDUSTRY AND ACADEMIA SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 DOE,OAK RIDGE OPERAT OFF,OAK RIDGE,TN 37831. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 2 EP ACSC PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG894 UT WOS:A1991FG89401459 ER PT J AU KAPLAN, M MOSES, DJ PARKER, WE VARDACI, E ALAMANOS, D ALEXANDER, JM BOGER, J LACEY, R MCMAHAN, MA GILFOYLE, G AF KAPLAN, M MOSES, DJ PARKER, WE VARDACI, E ALAMANOS, D ALEXANDER, JM BOGER, J LACEY, R MCMAHAN, MA GILFOYLE, G TI CHARGED-PARTICLE-EMISSION FROM HIGHLY EXCITED TB-149(STAR) COMPOSITE NUCLEI SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 CARNEGIE MELLON UNIV,PITTSBURGH,PA 15213. SUNY STONY BROOK,STONY BROOK,NY 11794. UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV RICHMOND,RICHMOND,VA 23173. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 3 EP NUCL PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG894 UT WOS:A1991FG89400003 ER EF