FN Thomson Reuters Web of Science™ VR 1.0 PT J AU DEINHAMMER, RS HO, MK PORTER, MD AF DEINHAMMER, RS HO, MK PORTER, MD TI SPECTROSCOPIC AND ELECTROCHEMICAL CHARACTERIZATION OF MONOLAYERS FORMED BY ELECTROCHEMICAL OXIDATION OF AMINES AT GLASSY-CARBON SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. 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 MAR 28 PY 1993 VL 205 BP 197 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101506 ER PT J AU STEWART, TB WINTER, NW PITZER, RM AF STEWART, TB WINTER, NW PITZER, RM TI MOLECULAR-ORBITAL CALCULATIONS OF SOLID LUBRICANTS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 OHIO STATE UNIV,DEPT CHEM,COLUMBUS,OH 43210. AEROSP CORP,CTR MECH & MAT TECHNOL,LOS ANGELES,CA 90009. LAWRENCE LIVERMORE NATL LAB,DEPT PHYS,LIVERMORE,CA 94550. 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 MAR 28 PY 1993 VL 205 BP 205 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101514 ER PT J AU JOHNSON, RW GARDELLA, JA PORTER, MD AF JOHNSON, RW GARDELLA, JA PORTER, MD TI QUANTITATIVE-ANALYSIS BY STATIC SIMS OF MIXED SELF-ASSEMBLED MONOLAYER FILMS ON GOLD AND COPPER SUBSTRATES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 SUNY BUFFALO,DEPT CHEM,BUFFALO,NY 14214. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,DEPT CHEM,AMES,IA 50011. NR 1 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 MAR 28 PY 1993 VL 205 BP 221 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101530 ER PT J AU WANG, J VAKNIN, D UPHAUS, RA AF WANG, J VAKNIN, D UPHAUS, RA TI MONOLAYER BEHAVIOR OF FULLERENE-AMINE ADDUCTS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. RI Vaknin, David/B-3302-2009 OI Vaknin, David/0000-0002-0899-9248 NR 0 TC 0 Z9 0 U1 0 U2 1 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 MAR 28 PY 1993 VL 205 BP 223 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101532 ER PT J AU ARNEY, DSJ BURNS, CJ SMITH, DC GREEN, JC SMITH, WH AF ARNEY, DSJ BURNS, CJ SMITH, DC GREEN, JC SMITH, WH TI SYNTHESIS AND PROPERTIES OF (BIS)PENTAMETHYLCYCLOPENTADIENYL ACTINIDE COMPLEXES CONTAINING TERMINAL ORGANOIMIDO AND OXO FUNCTIONAL-GROUPS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LOS ALAMOS NATL LAB,INORGAN & STRUCT CHEM GRP INC1,LOS ALAMOS,NM 87545. 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 MAR 28 PY 1993 VL 205 BP 225 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102577 ER PT J AU IVANICH, LS SAMUELS, WD NELSON, DA AF IVANICH, LS SAMUELS, WD NELSON, DA TI SYNTHESIS OF ARYLOXY POLYPHOSPHAZENES FOR PREPARATION OF PERVAPORATION MEMBRANES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 MONTANA COLL MINERAL SCI & TECHNOL, BUTTE, MT 59701 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. 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 MAR 28 PY 1993 VL 205 BP 225 EP CHED PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101080 ER PT J AU WEISSHAAR, DE LAMP, BD PORTER, MD AF WEISSHAAR, DE LAMP, BD PORTER, MD TI ELECTROCHEMICAL FORMATION OF ALKANETHIOLATE MONOLAYERS AT GOLD SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 0 TC 0 Z9 0 U1 0 U2 3 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 MAR 28 PY 1993 VL 205 BP 228 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101537 ER PT J AU OMER, MI PORTER, MD WEISSHAAR, DE AF OMER, MI PORTER, MD WEISSHAAR, DE TI FORMATION, STRUCTURE, AND STABILITY OF MONOLAYERS FORMED BY THE ADSORPTION OF N-ALKANETHIOLS ON GOLD FROM THE GAS-PHASE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. AUGUSTANA COLL,DEPT CHEM,SIOUX FALLS,SD 57197. 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 MAR 28 PY 1993 VL 205 BP 229 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101538 ER PT J AU CARTER, L OCONNOR, S SAMUELS, W AF CARTER, L OCONNOR, S SAMUELS, W TI DESIGN AND SYNTHESIS OF PHOSPHAZENE POLYMER FOR USE AS ION-EXCHANGE MEMBRANE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 XAVIER UNIV, NEW ORLEANS, LA 70125 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. 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 MAR 28 PY 1993 VL 205 BP 230 EP CHED PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101085 ER PT J AU SMITH, EL ALVES, CA ANDREGG, JW WATSON, SW BASTIAANS, GJ PORTER, MD SIPERKO, LM AF SMITH, EL ALVES, CA ANDREGG, JW WATSON, SW BASTIAANS, GJ PORTER, MD SIPERKO, LM TI DEPOSITION OF METALS AND ADSORPTION OF GASES AT END-GROUP FUNCTIONALIZED ALKANETHIOLATE MONOLAYERS AT GOLD SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,CTR ANALYT INSTRUMENTAT,AMES,IA 50011. IBM CORP,ADV TECHNOL LAB,ENDICOTT,NY 13760. 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 MAR 28 PY 1993 VL 205 BP 230 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101539 ER PT J AU ZAK, J FREEBURG, TL SIMMONS, NJ PORTER, MD AF ZAK, J FREEBURG, TL SIMMONS, NJ PORTER, MD TI FORMATION AND PROPERTIES OF ALKANETHIOLATE SUBMONOLAYERS AND MIXED MONOLAYERS AT GOLD SURFACES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. 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 MAR 28 PY 1993 VL 205 BP 231 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101540 ER PT J AU HEALY, MD SMITH, DC RUBIANO, RR SPRINGER, RW AF HEALY, MD SMITH, DC RUBIANO, RR SPRINGER, RW TI CHEMICAL VAPOR-DEPOSITION OF GROUP-IV CARBIDES FROM SINGLE SOURCE PRECURSORS - THE USE OF HOMOLEPTIC ALKYLS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. MIT,DEPT NUCL ENGN,CAMBRIDGE,MA 02139. NR 0 TC 0 Z9 0 U1 0 U2 4 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 MAR 28 PY 1993 VL 205 BP 234 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102586 ER PT J AU RAEKER, TJ PERKINS, LS HALSTEAD, DM DEPRISTO, AE AF RAEKER, TJ PERKINS, LS HALSTEAD, DM DEPRISTO, AE TI ENERGETICS AND DYNAMICS OF METAL METAL GROWTH SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. 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 MAR 28 PY 1993 VL 205 BP 234 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ983 UT WOS:A1993KQ98300839 ER PT J AU WANG, J BEDZYK, MJ CAFFREY, M AF WANG, J BEDZYK, MJ CAFFREY, M TI RESONANCE ENHANCED X-RAYS IN THIN-FILMS - A NEW STRUCTURE PROBE FOR MEMBRANES AND SURFACE-LAYERS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 OHIO STATE UNIV,DEPT CHEM,COLUMBUS,OH 43210. NORTHWESTERN UNIV,DEPT MAT SCI & ENGN,EVANSTON,IL 60208. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RI Bedzyk, Michael/B-7503-2009 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 MAR 28 PY 1993 VL 205 BP 237 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101546 ER PT J AU PINES, A AF PINES, A TI NMR-STUDIES OF CLUSTERS AND QUANTUM TUNNELING IN RESTRICTED GEOMETRIES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 UNIV CALIF BERKELEY,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. 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 MAR 28 PY 1993 VL 205 BP 242 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ983 UT WOS:A1993KQ98300847 ER PT J AU DUBOIS, DL BERNATIS, PR CURTIS, CJ HERRING, AM MIEDANER, A STEFFEY, BD AF DUBOIS, DL BERNATIS, PR CURTIS, CJ HERRING, AM MIEDANER, A STEFFEY, BD TI ELECTROCHEMICAL REDUCTION OF CO2 CATALYZED BY PALLADIUM PHOSPHINE COMPLEXES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL RENEWABLE ENERGY LAB,DIV BASIC SCI,GOLDEN,CO 80401. RI Herring, Andy/E-7088-2010 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 MAR 28 PY 1993 VL 205 BP 246 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102598 ER PT J AU PATTEN, TE NOVAK, BM AF PATTEN, TE NOVAK, BM TI THE SYNTHESIS OF COMB POLYMERS CONTAINING HELICAL POLYISOCYANATE SEGMENTS USING A MACROMOLECULAR TITANIUM(IV) CATALYST SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720. NR 0 TC 0 Z9 0 U1 0 U2 1 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 MAR 28 PY 1993 VL 205 BP 276 EP POLY PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ983 UT WOS:A1993KQ98301126 ER PT J AU ANCHELL, JL HESS, AC MOROKUMA, K AF ANCHELL, JL HESS, AC MOROKUMA, K TI AN ABINITIO MOLECULAR-ORBITAL COMPARISON STUDY OF H-2 INTERACTIONS WITH MGO AND LITHIUM DOPED MGO SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. INST MOLEC SCI, OKAZAKI, AICHI 444, JAPAN. 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 MAR 28 PY 1993 VL 205 BP 279 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101586 ER PT J AU NAVRATIL, JD AF NAVRATIL, JD TI MOLTEN-SALT OXIDATION OF MIXED WASTES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US DOE,CTR ENERGY TECHNOL ENGN,ROCKWELL INT,CANOGA PK,CA 91303. NR 0 TC 1 Z9 1 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 MAR 28 PY 1993 VL 205 BP 295 EP CHED PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101151 ER PT J AU PITTMAN, RM BELL, AT AF PITTMAN, RM BELL, AT TI RAMAN STUDIES OF TITANIA-SUPPORTED NIOBIA AND ITS INTERACTIONS WITH H-2, H2O AND NH3 SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. 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 MAR 28 PY 1993 VL 205 BP 304 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101610 ER PT J AU BELAK, JF BOERCKER, DB STOWERS, IF GLOSLI, JN AF BELAK, JF BOERCKER, DB STOWERS, IF GLOSLI, JN TI COMPUTER-SIMULATION OF NANOSCALE DEFORMATION OF CERAMIC MATERIALS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. 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 MAR 28 PY 1993 VL 205 BP 308 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101614 ER PT J AU LI, DQ SWANSON, BI AF LI, DQ SWANSON, BI TI SYNTHESIS AND CHARACTERIZATION OF SUPRAMOLECULAR LATTICES - PORPHYRIN BASED MULTILAYERS AND METAL CLUSTER MONOLAYERS ON OXIDE SURFACES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. 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 MAR 28 PY 1993 VL 205 BP 318 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101624 ER PT J AU LIEPINS, R JAHN, RK ELLIOTT, NE HUBBARD, KM AF LIEPINS, R JAHN, RK ELLIOTT, NE HUBBARD, KM TI MAGNETIC-FIELD PROCESSING OF POLYMERS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. 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 MAR 28 PY 1993 VL 205 BP 338 EP POLY PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ983 UT WOS:A1993KQ98301188 ER PT J AU HUNTLEY, DR AF HUNTLEY, DR TI SELECTIVITY OF ETHANE AND ETHYLENE FORMATION FROM THE REACTION OF ETHANETHIOL ON NI(110) SURFACES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 OAK RIDGE NATL LAB,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 MAR 28 PY 1993 VL 205 BP 342 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101646 ER PT J AU JACOBY, WA NIMLOS, MR BLAKE, DM AF JACOBY, WA NIMLOS, MR BLAKE, DM TI PHOTOCATALYTIC DESTRUCTION OF TRICHLOROETHYLENE IN AIR SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. NR 0 TC 0 Z9 0 U1 0 U2 1 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 MAR 28 PY 1993 VL 205 BP 344 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102696 ER PT J AU LASZLO, P PETRAKIS, L AF LASZLO, P PETRAKIS, L TI CHLORINE AND CHLOROCHEMICALS - THEIR GLOBAL IMPACT SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973. ECOLE POLYTECH,LAB DCFI,F-91128 PALAISEAU,FRANCE. 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 MAR 28 PY 1993 VL 205 BP 357 EP CHED PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101213 ER PT J AU SWANSON, BI BUSCHER, CT LI, DQ AF SWANSON, BI BUSCHER, CT LI, DQ TI CHROMOPHORIC BASED, COVALENTLY BONDED, SELF-ASSEMBLED MULTILAYER SUPRALATTICES ON INORGANIC OXIDE SURFACES AS NONLINEAR OPTICAL-MATERIALS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. 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 MAR 28 PY 1993 VL 205 BP 357 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102709 ER PT J AU WHYTE, HM AF WHYTE, HM TI USING VIDEOS FOR LEARNER-PACED INSTRUCTION SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LOS ALAMOS NATL LAB,IND HYG & SAFETY GRP,LOS ALAMOS,NM 87545. 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 MAR 28 PY 1993 VL 205 BP 378 EP CHED PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98101234 ER PT J AU BURRELL, AK BRYAN, JC CLARK, DL SMITH, WH BURNS, CJ SATTELBERGER, AP AF BURRELL, AK BRYAN, JC CLARK, DL SMITH, WH BURNS, CJ SATTELBERGER, AP TI REDUCTIONS OF TECHNETIUM IMIDO COMPLEXES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LOS ALAMOS NATL LAB,INORGAN & STRUCT CHEM GRP INC1,LOS ALAMOS,NM 87545. 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 MAR 28 PY 1993 VL 205 BP 391 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102743 ER PT J AU GIBSON, JK AF GIBSON, JK TI MASS-SPECTROMETRIC STUDY OF ALKALI PERTECHNETATE VAPOR SPECIES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 OAK RIDGE NATL LAB,DIV CHEM,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 MAR 28 PY 1993 VL 205 BP 398 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102750 ER PT J AU PERRY, DL ZUBKOWSKI, JD CATALAN, K VALENTE, E AF PERRY, DL ZUBKOWSKI, JD CATALAN, K VALENTE, E TI SINGLE-CRYSTAL X-RAY CRYSTALLOGRAPHIC STUDIES OF THE [CU(H2O)(1,10-PHENANTHROLINE)2] [NO3]2 COMPLEX SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 JACKSON STATE UNIV,DEPT CHEM,JACKSON,MS 39217. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. 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 MAR 28 PY 1993 VL 205 BP 404 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102756 ER PT J AU REYNOLDS, JG CHRISTOU, G HUFFMAN, JC AF REYNOLDS, JG CHRISTOU, G HUFFMAN, JC TI VANADIUM IN HEAVY CRUDE-OIL REFINING SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. INDIANA UNIV,DEPT CHEM,BLOOMINGTON,IN 47401. INDIANA UNIV,CTR MOLEC STRUCT,BLOOMINGTON,IN 47401. 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 MAR 28 PY 1993 VL 205 BP 440 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102792 ER PT J AU WISHART, JF SU, C AF WISHART, JF SU, C TI INTRAMOLECULAR ELECTRON-TRANSFER IN RUTHENIUM-MODIFIED COBALTOCYTOCHROME-C SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. 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 MAR 28 PY 1993 VL 205 BP 528 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102879 ER PT J AU RENNER, MW BARKIGIA, KM MEDFORTH, CJ SMITH, KM FAJER, J AF RENNER, MW BARKIGIA, KM MEDFORTH, CJ SMITH, KM FAJER, J TI CONSEQUENCES OF NONPLANARITY IN STERICALLY CROWDED PORPHYRINS - ANTIFERROMAGNETIC COUPLING IN CU(II) PI-CATION RADICALS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973. NR 1 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 MAR 28 PY 1993 VL 205 BP 569 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102920 ER PT J AU BURRELL, AK BRYAN, JC CLARK, DL MILLER, MM SATTELBERGER, AP BURNS, CJ AF BURRELL, AK BRYAN, JC CLARK, DL MILLER, MM SATTELBERGER, AP BURNS, CJ TI SYNTHESIS AND REACTIVITY OF TECHNETIUM IMIDO COMPLEXES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LOS ALAMOS NATL LAB,INORGAN & STRUCT CHEM GRP,LOS ALAMOS,NM 87545. 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 MAR 28 PY 1993 VL 205 BP 598 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102949 ER PT J AU MACQUEEN, DB ALLAN, C SPREER, LO OTVOS, JW CALVIN, M AF MACQUEEN, DB ALLAN, C SPREER, LO OTVOS, JW CALVIN, M TI AEROBIC OXIDATION OF A DIIRON BIS-MACROCYCLE TO A MONOMERIC OXO-MACROCYCLE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV PACIFIC,DEPT CHEM,STOCKTON,CA 95211. NR 1 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 MAR 28 PY 1993 VL 205 BP 612 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102963 ER PT J AU RUSH, JD BIELSKI, BHJ AF RUSH, JD BIELSKI, BHJ TI REACTIVITY OF FERRATE (VI) WITH AMINO-ACIDS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. NR 0 TC 1 Z9 1 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 MAR 28 PY 1993 VL 205 BP 615 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102966 ER PT J AU GLASSMAN, TE BURNS, CJ AF GLASSMAN, TE BURNS, CJ TI TECHNETIUM(VII, VI, AND V) AND RHENIUM(VII, VI AND V) OXO-CHLORIDE AND NITRIDO CHLORIDE COMPLEXES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 LOS ALAMOS NATL LAB,GRP INC1,LOS ALAMOS,NM 87545. 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 MAR 28 PY 1993 VL 205 BP 631 EP INOR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA KQ981 UT WOS:A1993KQ98102982 ER PT J AU CHANG, YF SOMORJAI, GA HEINEMANN, H AF CHANG, YF SOMORJAI, GA HEINEMANN, H TI OXYDEHYDROGENATION OF ETHANE OVER ZSM-5 ZEOLITE CATALYSTS - EFFECT OF STEAM SO APPLIED CATALYSIS A-GENERAL LA English DT Article DE ETHANE; OXYDEHYDROGENATION; ZEOLITES; ZSM-5 ID OXIDATIVE DEHYDROGENATION AB The oxydehydrogenation of ethane over zeolite based catalysts (H+-, Na+-, Ni2+-, Pt2+-, Ga3+-, and [V]-ZSM-5) was studied in the temperature range 450-600-degrees-C. Selectivity to ethylene and higher hydrocarbons close to 80% was achieved at 550-degrees-C. Basic (Na-ZSM-5) and neutral ([V]-ZSM-5) zeolite catalysts were shown to be more active and selective for the oxydehydrogenation of ethane than ZSM-5 in acid form. In addition to the oxydehydrogenation product, a significant amount of higher hydrocarbons (C3+) was produced when using zeolites containing Ga3+-, Pt2+, or Ni2+- cations. Na+-, V5+, and H+-exchanged ZSM-5 catalyst are less effective in facilitating the production of higher hydrocarbons (C3+). Steam often has a profound effect on the performance of zeolite based catalysts. The addition of steam can enhance their selectivity to hydrocarbon products and reduce their tendency to form methane. Relatively high conversion (ca. 43%) and high selectivity (ca. 78%) to hydrocarbons were achieved at temperatures around 550-degrees-C. Higher reaction temperature results in significant increase of the formation of methane while lower reaction temperature leads to lower selectivity to hydrocarbon products. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,1 CYCLOTRON RD,BERKELEY,CA 94720. NR 13 TC 24 Z9 25 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-860X J9 APPL CATAL A-GEN JI Appl. Catal. A-Gen. PD MAR 26 PY 1993 VL 96 IS 2 BP 305 EP 318 DI 10.1016/0926-860X(90)80018-A PG 14 WC Chemistry, Physical; Environmental Sciences SC Chemistry; Environmental Sciences & Ecology GA KU745 UT WOS:A1993KU74500018 ER PT J AU BARNABAS, MV WERST, DW TRIFUNAC, AD AF BARNABAS, MV WERST, DW TRIFUNAC, AD TI ELIMINATION AND ION MOLECULE REACTIONS OF HEXAMETHYLETHANE AND TRIMETHYLBUTANE RADICAL CATIONS IN ZSM-5 SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ELECTRON-SPIN-RESONANCE; BRANCHED ALKANES; MATRICES; SPECTROSCOPY; GENERATION; SPECTRA AB Hexamethylethane (HME) and trimethylbutane (TMB) radical cations produced in ZSM-5 zeolite by gamma radiolysis undergo an elimination process followed by an ion-molecule reaction. The tetramethylethylene radical cation intermediate formed by CH4 elimination from TMB+. is observed directly in the temperature range 120-200 K. The deprotonation product, (CH3)3CC.(CH3)2, of the cation-molecule reaction is observed for temperatures > 200 K. The isobutene radical cation formed by elimination of C4H10 from HME+. is not observed - presumably because of rapid ion-molecule reaction to form the 2-methylallyl radical, which is observed. RP BARNABAS, MV (reprint author), ARGONNE NATL LAB,DEPT CHEM,ARGONNE,IL 60439, USA. NR 23 TC 13 Z9 13 U1 0 U2 0 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 MAR 26 PY 1993 VL 204 IS 5-6 BP 435 EP 439 DI 10.1016/0009-2614(93)89182-H PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KU026 UT WOS:A1993KU02600008 ER PT J AU THOMAS, RC HOUSTON, JE MICHALSKE, TA CROOKS, RM AF THOMAS, RC HOUSTON, JE MICHALSKE, TA CROOKS, RM TI THE MECHANICAL RESPONSE OF GOLD SUBSTRATES PASSIVATED BY SELF-ASSEMBLING MONOLAYER FILMS SO SCIENCE LA English DT Article ID ADHESION AB Interfacial force microscopy has been used to show that a single layer of self-assembling molecules adsorbed on a gold substrate can prevent adhesion between gold and a tungsten probe. The passivated gold is able to elastically support large repulsive loads, with plots of load versus deformation closely following the Hertzian model. The gold shear-stress threshold for plastic deformation is determined to be approximately 1 gigapascal, which is in agreement with the theoretical value for the intrinsic gold-lattice stability. C1 SANDIA NATL LABS,DEPT SURFACE SCI,ALBUQUERQUE,NM 87185. RP THOMAS, RC (reprint author), UNIV NEW MEXICO,DEPT CHEM,ALBUQUERQUE,NM 87131, USA. NR 16 TC 94 Z9 94 U1 1 U2 5 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD MAR 26 PY 1993 VL 259 IS 5103 BP 1883 EP 1885 DI 10.1126/science.259.5103.1883 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KU172 UT WOS:A1993KU17200026 PM 17836246 ER PT J AU HENDERSON, CC CAHILL, PA AF HENDERSON, CC CAHILL, PA TI C60H2 - SYNTHESIS OF THE SIMPLEST C60 HYDROCARBON DERIVATIVE SO SCIENCE LA English DT Article ID BUCKMINSTERFULLERENE AB The reaction of C60 with BH3:tetrahydrofuran in toluene followed by hydrolysis yielded C60H2. This product was separated by high-performance liquid chromatography and characterized as the addition product of H-2 to a 6,6-ring fusion (1a1b isomer). The H-1 nuclear magnetic resonance (NMR) spectrum of the product remained a sharp singlet between -80-degrees and +100-degrees-C, which suggests a static structure on the NMR time scale. Hydrolysis of the proposed borane addition product with acetic acid-d1 or D2O yielded C60HD, and its 3J(HD) coupling constant is consistent with vicinal addition. The observation of a single C60H2 isomer is in complete agreement with earlier calculations that indicated that at most 2 of the 23 possible isomers of C60 would be observable at equilibrium at room temperature. These results suggest that organoborane chemistry may be applied to further functionalization of fullerenes. C1 SANDIA NATL LABS,DEPT 1811,ALBUQUERQUE,NM 87185. NR 13 TC 230 Z9 233 U1 1 U2 16 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD MAR 26 PY 1993 VL 259 IS 5103 BP 1885 EP 1887 DI 10.1126/science.259.5103.1885 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KU172 UT WOS:A1993KU17200027 PM 17836247 ER PT J AU WILLARDSON, BM POU, B YOSHIDA, T BITENSKY, MW AF WILLARDSON, BM POU, B YOSHIDA, T BITENSKY, MW TI COOPERATIVE BINDING OF THE RETINAL ROD G-PROTEIN, TRANSDUCIN, TO LIGHT-ACTIVATED RHODOPSIN SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID CYCLIC-GMP PHOSPHODIESTERASE; ALPHA-SUBUNIT; OUTER SEGMENTS; PHOTOEXCITED RHODOPSIN; PHOTORECEPTOR-MEMBRANES; CGMP PHOSPHODIESTERASE; MONOCLONAL-ANTIBODIES; SIGNAL TRANSDUCTION; CARBOXYL TERMINUS; 48-KDA PROTEIN AB Direct measurements of the binding between light-activated rhodopsin (Rho*) and transducin, the retinal rod G-protein, revealed a strongly cooperative interaction. Cooperativity was assessed by measuring the association of I-125-labeled transducin (G(t)) to Rho* in urea-stripped rod outer segment membranes at equilibrium. Analysis of I-125-G(t) binding curves gave a Hill coefficient of 1.8. These data were consistent with a two-site model in which binding of the first I-125-G(t) to Rho* increased the binding of the second I-125-G(t) almost-equal-to 40-fold (K(d) values were 80 +/- 30 and 1.9 +/- 0.7 nM, respectively). The effects of GDP on the binding were also investigated. GDP decreased the affinity between Rho* and G(t) almost-equal-to 100-fold but did not decrease the degree of cooperativity. Binding curves of I-125-G(t) in the presence of 1 mM GDP showed a Hill coefficient of 1.9. The data were also consistent with a two-binding site model in which binding of the first I-125-G(t) increased the binding of the second I-125-G(t) almost-equal-to 70-fold (K(d) values were 13.7 +/- 5.4 and 0.20 +/- 0.08 muM, respectively). The G(t)alpha subunit in the absence of G(t)betagamma also bound Rho* in a cooperative manner. These data implicate a role for the cooperative association of Rho* and G(t) in the light activation cascade of retinal rods. C1 LOS ALAMOS NATL LAB,DIV PHYS,BIOPHYS GRP,LOS ALAMOS,NM 87545. FU NEI NIH HHS [EY06816] NR 54 TC 48 Z9 49 U1 0 U2 0 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD MAR 25 PY 1993 VL 268 IS 9 BP 6371 EP 6382 PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA KT368 UT WOS:A1993KT36800045 PM 8454608 ER PT J AU CHASMAN, RR AF CHASMAN, RR TI VERY EXTENDED MINIMA IN THE A = 180 MASS REGION SO PHYSICS LETTERS B LA English DT Article ID SUPERDEFORMATION; NUCLEI AB A search for very extended nuclear shapes in the A = 180 mass region has been carried out in a three dimensional deformation space, using the cranked Strutinsky procedure. Many such minima have been found and their properties are described in detail. RP CHASMAN, RR (reprint author), ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439, USA. NR 18 TC 15 Z9 15 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 MAR 25 PY 1993 VL 302 IS 2-3 BP 134 EP 139 DI 10.1016/0370-2693(93)90372-O PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KT530 UT WOS:A1993KT53000003 ER PT J AU DYKSTRA, HM LYKKEN, JD RAITEN, EJ AF DYKSTRA, HM LYKKEN, JD RAITEN, EJ TI EXACT PATH-INTEGRALS BY EQUIVARIANT LOCALIZATION SO PHYSICS LETTERS B LA English DT Article ID INDEX THEOREM; GEOMETRY AB It is a common belief among field theorists that path integrals can be computed exactly only in a limited number of special cases, and that most of these cases are already known. However recent developments, which generalize the WKBJ method using equivariant cohomology, appear to contradict this folk wisdom. At the formal level, equivariant localization would seem to allow exact computation of phase space path integrals for an arbitrary partition function! To see how, and if, these methods really work in practice, we have applied them in explicit quantum mechanics examples. We show that the path integral for the 1D hydrogen atom, which is not WKBJ exact, is localizable and computable using the more general formalism. We find however considerable ambiguities in this approach, which we can only partially resolve. In addition, we find a large class of quantum mechanics examples where the localization procedure breaks down completely. C1 FERMILAB NATL ACCELERATOR LAB,THEORY GRP,BATAVIA,IL 60510. RP DYKSTRA, HM (reprint author), UNIV MASSACHUSETTS,DEPT PHYS & ASTRON,AMHERST,MA 01003, USA. NR 10 TC 8 Z9 8 U1 0 U2 1 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 MAR 25 PY 1993 VL 302 IS 2-3 BP 223 EP 229 DI 10.1016/0370-2693(93)90388-X PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KT530 UT WOS:A1993KT53000019 ER PT J AU BERN, Z DIXON, L KOSOWER, DA AF BERN, Z DIXON, L KOSOWER, DA TI DIMENSIONALLY REGULATED ONE-LOOP INTEGRALS SO PHYSICS LETTERS B LA English DT Article ID ALGEBRAIC REDUCTION; FEYNMAN DIAGRAMS; SCALAR INTEGRALS AB We describe methods for evaluating one-loop integrals in 4 - 2epsilon dimensions. We give a recursion relation that expresses the scalar n-point integral as a cyclicly symmetric combination of (n - 1)-point integrals. The computation of such integrals thus reduces to the calculation of box diagrams (n = 4). The tensor integrals required in gauge theory may be obtained by differentiating the scalar integral with respect to certain combinations of the kinematic variables. Such relations also lead to differential equations for scalar integrals, For box integrals with massless internal lines these differential equations are easy to solve. C1 STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. CERN,DIV THEORY,CH-1211 GENEVA 23,SWITZERLAND. CTR ETUD SACLAY,SERV PHYS THEOR SACLAY,F-91191 GIF SUR YVETTE,FRANCE. RP BERN, Z (reprint author), UNIV CALIF LOS ANGELES,DEPT PHYS,LOS ANGELES,CA 90024, USA. NR 20 TC 154 Z9 154 U1 0 U2 2 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 MAR 25 PY 1993 VL 302 IS 2-3 BP 299 EP 308 DI 10.1016/0370-2693(93)90400-C PG 10 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KT530 UT WOS:A1993KT53000031 ER PT J AU CORDS, D BOYER, J BUTLER, F GIDAL, G ABRAMS, GS AMIDEI, D BADEN, AR BARKLOW, T BOYARSKI, AM BURCHAT, PR BURKE, DL DORFAN, JM FELDMAN, GJ GLADNEY, L GOLD, MS GOLDHABER, G HAGGERTY, J HANSON, G HAYES, K HERRUP, D HOLLEBEEK, RJ INNES, WR JAROS, JA JURICIC, I KADYK, JA KARLEN, D LANKFORD, AJ LARSEN, RR LECLAIRE, BW LEVI, ME LOCKYER, NS LUTH, V NELSON, ME ONG, RA PERL, ML RILES, K ROWSON, PC SCHAAD, T SCHELLMAN, H SCHMIDKE, WB TRILLING, GH WOOD, DR YELTON, JM AF CORDS, D BOYER, J BUTLER, F GIDAL, G ABRAMS, GS AMIDEI, D BADEN, AR BARKLOW, T BOYARSKI, AM BURCHAT, PR BURKE, DL DORFAN, JM FELDMAN, GJ GLADNEY, L GOLD, MS GOLDHABER, G HAGGERTY, J HANSON, G HAYES, K HERRUP, D HOLLEBEEK, RJ INNES, WR JAROS, JA JURICIC, I KADYK, JA KARLEN, D LANKFORD, AJ LARSEN, RR LECLAIRE, BW LEVI, ME LOCKYER, NS LUTH, V NELSON, ME ONG, RA PERL, ML RILES, K ROWSON, PC SCHAAD, T SCHELLMAN, H SCHMIDKE, WB TRILLING, GH WOOD, DR YELTON, JM TI INCLUSIVE CHARGED HADRON AND K0 PRODUCTION IN 2-PHOTON INTERACTIONS SO PHYSICS LETTERS B LA English DT Article ID PHOTON-PHOTON INTERACTIONS; TRANSVERSE-MOMENTUM; JET PRODUCTION; HIGH-ENERGY; COLLISIONS AB The inclusive transverse momentum distributions of charged hadrons and K0's produced in tagged photon-photon collisions, are measured and compared to model calculations up to a p(T) of 5 GeV/c. The relative abundance of K0's favor the inclusion of charm. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. HARVARD UNIV,DEPT PHYS,CAMBRIDGE,MA 02138. STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94305. RP CORDS, D (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 18 TC 9 Z9 9 U1 1 U2 1 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 MAR 25 PY 1993 VL 302 IS 2-3 BP 341 EP 344 DI 10.1016/0370-2693(93)90406-8 PG 4 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KT530 UT WOS:A1993KT53000037 ER PT J AU BAUER, DA BELCINSKI, R BERG, RC BINGHAM, HH BUCHANAN, CD CALDWELL, DO CHUN, SB CLARK, AR DAHL, OI DAOUDI, M EASTMAN, JJ EISNER, AM FAIRFIELD, KH GODFREY, G GREENBAUM, GS HAUPTMAN, JM HOFMANN, W HOLTZAPPLE, RL KHACHERYAN, S KNOPFLE, KT KOFLER, RR LAMBERT, DJ LAYTER, JG LIN, WT LOKEN, SC LU, A LYNCH, GR LYS, JE MADARAS, RJ MARSISKE, H MASEK, GE MILLER, ES NICOL, NA NYGREN, DR OYANG, YT PAAR, HP PALOUNEK, APT PELLETT, DE RONAN, MT ROSS, RR SHAPIRO, G SHEN, BC STEPHENS, RW STEVENSON, ML STRAUSS, MG SULLIVAN, MK VERNON, W WANG, EM WANG, YX WENZEL, WA YAMAMOTO, H YELLIN, SJ YOST, GP ZAPALAC, G ZEITLIN, C AF BAUER, DA BELCINSKI, R BERG, RC BINGHAM, HH BUCHANAN, CD CALDWELL, DO CHUN, SB CLARK, AR DAHL, OI DAOUDI, M EASTMAN, JJ EISNER, AM FAIRFIELD, KH GODFREY, G GREENBAUM, GS HAUPTMAN, JM HOFMANN, W HOLTZAPPLE, RL KHACHERYAN, S KNOPFLE, KT KOFLER, RR LAMBERT, DJ LAYTER, JG LIN, WT LOKEN, SC LU, A LYNCH, GR LYS, JE MADARAS, RJ MARSISKE, H MASEK, GE MILLER, ES NICOL, NA NYGREN, DR OYANG, YT PAAR, HP PALOUNEK, APT PELLETT, DE RONAN, MT ROSS, RR SHAPIRO, G SHEN, BC STEPHENS, RW STEVENSON, ML STRAUSS, MG SULLIVAN, MK VERNON, W WANG, EM WANG, YX WENZEL, WA YAMAMOTO, H YELLIN, SJ YOST, GP ZAPALAC, G ZEITLIN, C TI STUDY OF CHI-C2 PRODUCTION IN PHOTON PHOTON COLLISIONS - TPC/2-GAMMA COLLABORATION SO PHYSICS LETTERS B LA English DT Article ID RADIATIVE-CORRECTIONS; 2-PHOTON PROCESSES; CHARMONIUM STATES; MESONS AB Two-photon production of the charmonium state chi(c) has been studied by the TPC/Two-Gamma experiment at the SLAC e+e-collider PEP. We observe evidence of the chi(c2) state in the channel gammagamma --> chi(c2), chi(c2) --> gammaJ/psi, J/psi --> l+l- and obtain a value of GAMMA(gammagamma)(chi(c2)) = 3.4 +/- 1.7 +/- 0.9 keV. This is the first observation of the two-photon production of a chi(c) state. Comparison is made with previous experimental results and QCD predictions for GAMMA(gammagamma)(chi(c2)). C1 UNIV MASSACHUSETTS,AMHERST,MA 01003. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024. UNIV CALIF RIVERSIDE,RIVERSIDE,CA 92521. UNIV CALIF STANFORD,INTERCAMPUS INST RES PARTICLE ACCELERATORS,STANFORD,CA 94305. IOWA STATE UNIV SCI & TECHNOL,AMES,IA 50011. STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94305. UNIV CALIF DAVIS,DAVIS,CA 95616. UNIV CALIF SAN DIEGO,LA JOLLA,CA 92093. MAX PLANCK INST NUCL PHYS,W-6900 HEIDELBERG 1,GERMANY. RP BAUER, DA (reprint author), UNIV CALIF SANTA BARBARA,SANTA BARBARA,CA 93106, USA. NR 24 TC 16 Z9 16 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 MAR 25 PY 1993 VL 302 IS 2-3 BP 345 EP 350 DI 10.1016/0370-2693(93)90407-9 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KT530 UT WOS:A1993KT53000038 ER PT J AU ABREU, P ADAM, W ADYE, T AGASI, E ALEKSAN, R ALEKSEEV, GD ALGERI, A ALLEN, P ALMEHED, S ALVSVAAG, SJ AMALDI, U ANASSONTZIS, EG ANDREAZZA, A ANTILOGUS, P APEL, WD APSIMON, RJ ARNOUD, Y ASMAN, B AUGUSTIN, JE AUGUSTINUS, A BAILLON, P BAMBADE, P BARAO, F BARATE, R BARBIELLINI, G BARDIN, DY BARKER, GJ BARONCELLI, A BARRING, O BARRIO, JA BARTL, W BATES, MJ BATTAGLIA, M BAUBILLIER, M BECKS, KH BEESTON, CJ BEGALLI, M BEILLIERE, P BELOKOPYTOV, Y BELTRAN, P BENEDIC, D BENVENUTI, AC BERGGREN, M BERTRAND, D BIANCHI, F BILENKY, MS BILLOIR, P BJARNE, J BLOCH, D BLYTH, S BOCCI, V BOGOLUBOV, PN BOLOGNESE, T BONESINI, M BONIVENTO, W BOOTH, PSL BORISOV, G BORNER, H BOSIO, C BOSTJANCIC, B BOSWORTH, S BOTNER, O BOUQUET, B BOURDARIOS, C BOWCOCK, TJV BOZZO, M BRAIBANT, S BRANCHINI, P BRAND, KD BRENNER, RA BRIAND, H BRICMAN, C BROWN, RCA BRUMMER, N BRUNET, JM BUGGE, L BURAN, T BURMEISTER, H BUYTAERT, JAMA CACCIA, M CALVI, M ROZAS, AJC CAMPION, R CAMPORESI, T CANALE, V CAO, F CARENA, F CARROLL, L GIMENEZ, MVC CATTAI, A CAVALLO, FR CERRITO, L CHABAUD, V CHAN, A CHARPENTIER, P CHAUSSARD, L CHAUVEAU, J CHECCHIA, P CHELKOV, GA CHEVALIER, L CHLIAPNIKOV, P CHOROWICZ, V CHRIN, JTM CLARA, MP COLLINS, P CONTRERAS, JL CONTRI, R CORTINA, E COSME, G COUCHOT, F CRAWLEY, HB CRENNELL, D CROSETTI, G CROZON, M MAESTRO, JC CZELLAR, S DAHLJENSEN, E DALMAGNE, B DAM, M DAMGAARD, G DARBO, G DAUBIE, E DAUM, A DAUNCEY, PD DAVENPORT, M DAVID, P DAVIES, J DASILVA, W DEFOIX, C DELPIERRE, P DEMARIA, N DEANGELIS, A DEBOECK, H DEBOER, W DECLERCQ, C LASO, MDMD DEGROOT, N DELAVAISSIERE, C DELOTTO, B DEMIN, A DIJKSTRA, H DICIACCIO, L DJAMA, F DOLBEAU, J DONSZELMANN, M DOROBA, K DRACOS, M DREES, J DRIS, M DUFOUR, Y DUPONT, F EEK, LO EEROLA, PAM EHRET, R EKELOF, T EKSPONG, G PEISERT, AE 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JARRY, P JEANMARIE, B JOHANSSON, EK JOHNSON, D JONKER, M JONSSON, L JUILLOT, P KALKANIS, G KALMUS, G KAPUSTA, F KARLSSON, M KARVELAS, E KATSANEVAS, S KATSOUFIS, EC KERANEN, R KESTEMAN, J KHOMENKO, BA KHOVANSKI, NN KING, B KJAER, NJ KLEIN, H KLOVNING, A KLUIT, P KOCHMEHRIN, A KOEHNE, JH KOENE, B KOKKINIAS, P KORATZINOS, M KORCYL, K KORYTOV, AV KOSTIOUKHINE, V KOURKOUMELIS, C KOUZNETSOV, O KRAMER, PH KROLIKOWSKI, J KRONKVIST, I KRUENERMARQUIS, U KUCEWICZ, W KULKA, K KURVINEN, K LACASTA, C LAMBROPOULOS, C LAMSA, JW LANCERI, L LAPIN, V LAUGIER, JP LAUHAKANGAS, R LEDER, G LEDROIT, F LEITNER, R LEMOIGNE, Y LEMONNE, J LENZEN, G LEPELTIER, V LESIAK, T LEVY, JM LIEB, E LIKO, D LINDGREN, J LINDNER, R LIPNIACKA, A LIPPI, I LOERSTAD, B LOKAJICEK, M LOKEN, JG LOPEZFERNANDEZ, A AGUERA, MAL LOS, M LOUKAS, D LOZANO, JJ LUTZ, P LYONS, L MAEHLUM, G MAILLARD, J MAIO, A MALTEZOS, A MANDL, F MARCO, J MARGONI, M MARIN, JC MARKOU, A MARON, T MARTI, S MATHIS, L MATORRAS, F MATTEUZZI, C MATTHIAE, G MAZZUCATO, M MCCUBBIN, M MCKAY, R MCNULTY, R MEOLA, G MERONI, C MEYER, WT MICHELOTTO, M MIKULEC, I MIRABITO, L MITAROFF, WA MITSELMAKHER, GV MJOERNMARK, U MOA, T MOELLER, R MOENIG, K MONGE, MR MORETTINI, P MUELLER, H MURRAY, WJ MYATT, G NAVARRIA, FL NEGRI, P NIELSEN, BS NIJJHAR, B NIKOLAENKO, V NILSEN, PES NISS, P OBRAZTSOV, V OLSHEVSKI, AG ORAVA, R OSTANKOV, A OSTERBERG, K OURAOU, A PAGANONI, M PAIN, R PAPADOPOULOU, TD PAPE, L PARODI, F PASSERI, A PEGORARO, M PENNANEN, J PERALTA, L PERNEGGER, H PERNICKA, M PERROTTA, A PETRIDOU, C PETROLINI, A PETTERSEN, TE PIERRE, F PIMENTA, M PINGOT, O PLASZCZYNSKI, S PODOBRIN, O POL, ME POLOK, G POROPAT, P PRIVITERA, P PULLIA, A RADOJICIC, D RAGAZZI, S RAHMANI, H RATOFF, PN READ, AL REDAELLI, NG REGLER, M REID, D RENTON, PB RESVANIS, LK RICHARD, F RICHARDSON, M RIDKY, J RINAUDO, G RODITI, I ROMERO, A RONCAGLIOLO, I RONCHESE, P RONNQVIST, C ROSENBERG, EI ROSSI, S ROSSI, U ROSSO, E ROUDEAU, P ROVELLI, T RUCKSTUHL, W RUHLMANNKLEIDER, V RUIZ, A RYBIN, A SAARIKKO, H SACQUIN, Y SAJOT, G SALT, J SANCHEZ, J SANNINO, M SCHAEL, S SCHNEIDER, H SCHULZE, B SCHYNS, MAE SCIOLLA, G SCURI, F SEGAR, AM SEITZ, A SEKULIN, R SESSA, M SETTE, G SEUFERT, R SHELLARD, RC SICCAMA, I SIEGRIST, P SIMONETTI, S SIMONETTO, F SISAKIAN, AN SKJEVLING, G SMADJA, G SMITH, GR SOSNOWSKI, R SOUZASANTOS, D SPASSOFF, TS SPIRITI, E SQUARCIA, S STAECK, H STANESCU, C STAPNES, S STAVROPOULOS, G STICHELBAUT, F STOCCHI, A STRAUSS, J STRAVER, J STRUB, R STUGU, B SZCZEKOWSKI, M SZEPTYCKA, M SZYMANSKI, P TABARELLI, T TCHIKILEV, O THEODOSIOU, GE TILQUIN, A TIMMERMANS, J TIMOFEEV, VG TKATCHEV, LG TODOROV, T TOET, DZ TOKER, O TOME, B TORASSA, E TORTORA, L TREILLE, D TREVISAN, U TRISCHUK, W TRISTRAM, G TRONCON, C TSIROU, A TSYGANOV, EN TURLUER, ML TUUVA, T TYAPKIN, IA TYNDEL, M TZAMARIAS, S UEBERSCHAER, S ULLALAND, O UVAROV, V VALENTI, G VALLAZZA, E FERRER, JAV VANDERVELDE, C VANAPELDOORN, GW VANDAM, P VANDERHEIJDEN, M VANDONINCK, WK VAZ, P VEGNI, G VENTURA, L VENUS, W VERBEURE, F VERLATO, M 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BJARNE, J BLOCH, D BLYTH, S BOCCI, V BOGOLUBOV, PN BOLOGNESE, T BONESINI, M BONIVENTO, W BOOTH, PSL BORISOV, G BORNER, H BOSIO, C BOSTJANCIC, B BOSWORTH, S BOTNER, O BOUQUET, B BOURDARIOS, C BOWCOCK, TJV BOZZO, M BRAIBANT, S BRANCHINI, P BRAND, KD BRENNER, RA BRIAND, H BRICMAN, C BROWN, RCA BRUMMER, N BRUNET, JM BUGGE, L BURAN, T BURMEISTER, H BUYTAERT, JAMA CACCIA, M CALVI, M ROZAS, AJC CAMPION, R CAMPORESI, T CANALE, V CAO, F CARENA, F CARROLL, L GIMENEZ, MVC CATTAI, A CAVALLO, FR CERRITO, L CHABAUD, V CHAN, A CHARPENTIER, P CHAUSSARD, L CHAUVEAU, J CHECCHIA, P CHELKOV, GA CHEVALIER, L CHLIAPNIKOV, P CHOROWICZ, V CHRIN, JTM CLARA, MP COLLINS, P CONTRERAS, JL CONTRI, R CORTINA, E COSME, G COUCHOT, F CRAWLEY, HB CRENNELL, D CROSETTI, G CROZON, M MAESTRO, JC CZELLAR, S DAHLJENSEN, E DALMAGNE, B DAM, M DAMGAARD, G DARBO, G DAUBIE, E DAUM, A DAUNCEY, PD DAVENPORT, M DAVID, P DAVIES, J DASILVA, W DEFOIX, C DELPIERRE, P DEMARIA, N DEANGELIS, A DEBOECK, H DEBOER, W DECLERCQ, C LASO, MDMD DEGROOT, N DELAVAISSIERE, C DELOTTO, B DEMIN, A DIJKSTRA, H DICIACCIO, L DJAMA, F DOLBEAU, J DONSZELMANN, M DOROBA, K DRACOS, M DREES, J DRIS, M DUFOUR, Y DUPONT, F EEK, LO EEROLA, PAM EHRET, R EKELOF, T EKSPONG, G PEISERT, AE ENGEL, JP ERSHAIDAT, N FASSOULIOTIS, D FEINDT, M FENYUK, A ALONSO, MF FERRER, A FILIPPAS, TA FIRESTONE, A FOETH, H FOKITIS, E FONTANELLI, F FORBES, KAJ FOUSSET, JL FRANCON, S FRANEK, B FRENKIEL, P FRIES, DC FRODESEN, AG FRUHWIRTH, R FULDAQUENZER, F FURNIVAL, K FURSTENAU, H FUSTER, J GAMBA, D GARCIA, C GARCIA, J GASPAR, C GASPARINI, U GAVILLET, P GAZIS, EN GERBER, JP GIACOMELLI, P GOKIELI, R GOLOB, B GOLOVATYUK, VM CADENAS, JJGY GOOBAR, A GOPAL, G GORSKI, M GRACCO, V GRANT, A GRARD, F GRAZIANI, E GROSDIDIER, G GROSS, E GROSSEWIESMANN, P GROSSETETE, B GUMENYUK, S GUY, J HAEDINGER, U HAHN, F HAHN, M HAIDER, S HAJDUK, Z HAKANSSON, A HALLGREN, A HAMACHER, K DEMONCHENAULT, GH HAO, W HARRIS, FJ HEDBERG, V HENKES, T HERNANDEZ, JJ HERQUET, P HERR, H HESSING, TL HIETANEN, I HIGGINS, CO HIGON, E HILKE, HJ HODGSON, SD HOFMOKL, T HOLMES, R HOLMGREN, SO HOLTHUIZEN, D HONORE, PF HOOPER, JE HOULDEN, M HRUBEC, J HUET, K HULTH, PO HULTQVIST, K IOANNOU, P IVERSEN, PS JACKSON, JN JALOCHA, P JARLSKOG, G JARRY, P JEANMARIE, B JOHANSSON, EK JOHNSON, D JONKER, M JONSSON, L JUILLOT, P KALKANIS, G KALMUS, G KAPUSTA, F KARLSSON, M KARVELAS, E KATSANEVAS, S KATSOUFIS, EC KERANEN, R KESTEMAN, J KHOMENKO, BA KHOVANSKI, NN KING, B KJAER, NJ KLEIN, H KLOVNING, A KLUIT, P KOCHMEHRIN, A KOEHNE, JH KOENE, B KOKKINIAS, P KORATZINOS, M KORCYL, K KORYTOV, AV KOSTIOUKHINE, V KOURKOUMELIS, C KOUZNETSOV, O KRAMER, PH KROLIKOWSKI, J KRONKVIST, I KRUENERMARQUIS, U KUCEWICZ, W KULKA, K KURVINEN, K LACASTA, C LAMBROPOULOS, C LAMSA, JW LANCERI, L LAPIN, V LAUGIER, JP LAUHAKANGAS, R LEDER, G LEDROIT, F LEITNER, R LEMOIGNE, Y LEMONNE, J LENZEN, G LEPELTIER, V LESIAK, T LEVY, JM LIEB, E LIKO, D LINDGREN, J LINDNER, R LIPNIACKA, A LIPPI, I LOERSTAD, B LOKAJICEK, M LOKEN, JG LOPEZFERNANDEZ, A AGUERA, MAL LOS, M LOUKAS, D LOZANO, JJ LUTZ, P LYONS, L MAEHLUM, G MAILLARD, J MAIO, A MALTEZOS, A MANDL, F MARCO, J MARGONI, M MARIN, JC MARKOU, A MARON, T MARTI, S MATHIS, L MATORRAS, F MATTEUZZI, C MATTHIAE, G MAZZUCATO, M MCCUBBIN, M MCKAY, R MCNULTY, R MEOLA, G MERONI, C MEYER, WT MICHELOTTO, M MIKULEC, I MIRABITO, L MITAROFF, WA MITSELMAKHER, GV MJOERNMARK, U MOA, T MOELLER, R MOENIG, K MONGE, MR MORETTINI, P MUELLER, H MURRAY, WJ MYATT, G NAVARRIA, FL NEGRI, P NIELSEN, BS NIJJHAR, B NIKOLAENKO, V NILSEN, PES NISS, P OBRAZTSOV, V OLSHEVSKI, AG ORAVA, R OSTANKOV, A OSTERBERG, K OURAOU, A PAGANONI, M PAIN, R PAPADOPOULOU, TD PAPE, L PARODI, F PASSERI, A PEGORARO, M PENNANEN, J PERALTA, L PERNEGGER, H PERNICKA, M PERROTTA, A PETRIDOU, C PETROLINI, A PETTERSEN, TE PIERRE, F PIMENTA, M PINGOT, O PLASZCZYNSKI, S PODOBRIN, O POL, ME POLOK, G POROPAT, P PRIVITERA, P PULLIA, A RADOJICIC, D RAGAZZI, S RAHMANI, H RATOFF, PN READ, AL REDAELLI, NG REGLER, M REID, D RENTON, PB RESVANIS, LK RICHARD, F RICHARDSON, M RIDKY, J RINAUDO, G RODITI, I ROMERO, A RONCAGLIOLO, I RONCHESE, P RONNQVIST, C ROSENBERG, EI ROSSI, S ROSSI, U ROSSO, E ROUDEAU, P ROVELLI, T RUCKSTUHL, W RUHLMANNKLEIDER, V RUIZ, A RYBIN, A SAARIKKO, H SACQUIN, Y SAJOT, G SALT, J SANCHEZ, J SANNINO, M SCHAEL, S SCHNEIDER, H SCHULZE, B SCHYNS, MAE SCIOLLA, G SCURI, F SEGAR, AM SEITZ, A SEKULIN, R SESSA, M SETTE, G SEUFERT, R SHELLARD, RC SICCAMA, I SIEGRIST, P SIMONETTI, S SIMONETTO, F SISAKIAN, AN SKJEVLING, G SMADJA, G SMITH, GR SOSNOWSKI, R SOUZASANTOS, D SPASSOFF, TS SPIRITI, E SQUARCIA, S STAECK, H STANESCU, C STAPNES, S STAVROPOULOS, G STICHELBAUT, F STOCCHI, A STRAUSS, J STRAVER, J STRUB, R STUGU, B SZCZEKOWSKI, M SZEPTYCKA, M SZYMANSKI, P TABARELLI, T TCHIKILEV, O THEODOSIOU, GE TILQUIN, A TIMMERMANS, J TIMOFEEV, VG TKATCHEV, LG TODOROV, T TOET, DZ TOKER, O TOME, B TORASSA, E TORTORA, L TREILLE, D TREVISAN, U TRISCHUK, W TRISTRAM, G TRONCON, C TSIROU, A TSYGANOV, EN TURLUER, ML TUUVA, T TYAPKIN, IA TYNDEL, M TZAMARIAS, S UEBERSCHAER, S ULLALAND, O UVAROV, V VALENTI, G VALLAZZA, E FERRER, JAV VANDERVELDE, C VANAPELDOORN, GW VANDAM, P VANDERHEIJDEN, M VANDONINCK, WK VAZ, P VEGNI, G VENTURA, L VENUS, W VERBEURE, F VERLATO, M VERTOGRADOV, LS VILANOVA, D VINCENT, P VITALE, L VLASOV, E VODOPYANOV, AS VOLLMER, M VOULGARIS, G VOUTILAINEN, M VRBA, V WAHLEN, H WALCK, C WALDNER, F WAYNE, M WEHR, A WEIERSTALL, M WEILHAMMER, P WERNER, J WETHERELL, AM WICKENS, JH WILKINSON, GR WILLIAMS, WSC WINTER, M WITEK, M WORMSER, G WOSCHNAGG, K YAMDAGNI, N YEPES, P ZAITSEV, A ZALEWSKA, A ZALEWSKI, P ZAVRTANIK, D ZEYGOLATAKOS, E ZHANG, G ZIMIN, NI ZITO, M ZUBERI, R FUNCHAL, RZ ZUMERLE, G ZUNIGA, J TI A MEASUREMENT OF THE TAU LIFETIME SO PHYSICS LETTERS B LA English DT Article ID LEPTONS AB The tau lepton lifetime is measured using four different methods with the DELPHI detector. Three measurements using one prong decays are combined, accounting for correlations, resulting in tau(tau) = 298 +/- 7 (stat.) +/- 4 (syst.) fs while the decay length distribution of three prong decays gives tau(tau) = 298 +/- 13 (stat.) +/- 5 (syst.) fs. The combined result is tau(tau) = 298 +/- 7 fs. The ratio of the Fermi coupling constant from tau decay relative to that from muon decay is found to be 0.985 +/- 0.013, compatible with lepton universality. C1 UNIV PARIS 07,F-75252 PARIS 5,FRANCE. INFN,I-00173 ROME,ITALY. UNIV BOLOGNA,DIPARTIMENTO FIS,I-40126 BOLOGNA,ITALY. UNIV INSTELLING ANTWERP,DEPT PHYS,B-2610 WILRIJK,BELGIUM. UNIV LJUBLJANA,DEPT PHYS,YU-61000 LJUBLJANA,SLOVENIA. UNIV ETAT MONS,FAC SCI,B-7000 MONS,BELGIUM. INFN,I-16146 GENOA,ITALY. UNIV UPPSALA,DEPT RADIAT SCI,S-75121 UPPSALA,SWEDEN. UNIV PADUA,DIPARTIMENTO FIS,I-35131 PADUA,ITALY. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. UNIV WARSAW,PL-00681 WARSAW,POLAND. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. NIKHEF H,1009 DB AMSTERDAM,NETHERLANDS. DAPNIA,DSM,CTR ETUD SACLAY,F-91191 GIF SUR YVETTE,FRANCE. JOINT INST NUCL RES,MOSCOW 101000,RUSSIA. VALENCIA CSIC,IFIC,E-46100 BURJASSOT,SPAIN. UNIV VALENCIA,DFAMN,E-46100 BURJASSOT,SPAIN. UNIV LUND,DEPT PHYS,S-22363 LUND,SWEDEN. UNIV BERGEN,DEPT PHYS,N-5007 BERGEN,NORWAY. UNIV ATHENS,PHYS LAB,GR-10680 ATHENS,GREECE. INFN,I-20133 MILAN,ITALY. UNIV LYON,IPNL,IN2P3,CNRS,F-69622 VILLEURBANNE,FRANCE. UNIV PARIS 11,IN2P3,ACCELERATEUR LINEAIRE LAB,CNRS,F-91405 ORSAY,FRANCE. UNIV GRENOBLE 1,INST SCI NUCL,F-38026 GRENOBLE,FRANCE. INFN,I-34127 TRIESTE,ITALY. UNIV OXFORD,NUCL PHYS LAB,OXFORD OX1 3RH,ENGLAND. IST NAZL FIS NUCL,IST SUPER SANITA,I-00161 ROME,ITALY. UNIV COMPLUTENSE,E-28040 MADRID,SPAIN. AUSTRIAN ACAD SCI,INST HOCHENERGIEPHYS,A-1050 VIENNA,AUSTRIA. UNIV PARIS VI,LPNHE,F-75252 PARIS 05,FRANCE. PONTIFICIA UNIV CATOLICA,DEPT FIS,BR-22453 RIO JANEIRO,BRAZIL. PROTVINO HIGH ENERGY PHYS INST,PROTVINO 142284,RUSSIA. NCSR DEMOKRITOS,INST NUCL PHYS,GR-15310 ATHENS,GREECE. ULP,CTR RECH NUCL,IN2P3,CNRS,F-67037 STRASBOURG,FRANCE. INFN,I-40126 BOLOGNA,ITALY. VUB,ULB,IIHE,B-1050 BRUSSELS,BELGIUM. UNIV TURIN,DIPARTIMENTO FIS SPERIMENTALE,I-10125 TURIN,ITALY. INFN,I-10125 TURIN,ITALY. UNIV ROME 2,DIPARTIMENTO FIS,I-00173 ROME,ITALY. UNIV GENOA,DIPARTIMENTO FIS,I-16146 GENOA,ITALY. INFN,I-35131 PADUA,ITALY. UNIV OSLO,DEPT PHYS,N-1000 OSLO 3,NORWAY. UNIV SANTANDER,FAC CIENCIAS,E-39005 SANTANDER,SPAIN. NIELS BOHR INST,DK-2100 COPENHAGEN 0,DENMARK. INST NUCL STUDIES,PL-00681 WARSAW,POLAND. NATL TECH UNIV ATHENS,DEPT PHYS,GR-15773 ATHENS,GREECE. UNIV AIX MARSEILLE 2,CPP,IN2P3,CNRS,F-13288 MARSEILLE 09,FRANCE. INST NUCL PHYS,HIGH ENERGY PHYS LAB,PL-30055 KRAKOW 30,POLAND. CHARLES UNIV,NUCL CTR MFF,CS-18000 PRAGUE 8,CZECHOSLOVAKIA. UNIV UDINE,IST FIS,I-33100 UDINE,ITALY. UNIV GESAMTHSCH WUPPERTAL,FACHBEREICH PHYS,W-5600 WUPPERTAL 1,GERMANY. COLL FRANCE,PHYS CORPUSCULAIRE LAB,IN2P3,CNRS,F-75231 PARIS 05,FRANCE. UNIV LIVERPOOL,DEPT PHYS,LIVERPOOL L69 3BX,ENGLAND. UNIV LJUBLJANA,J STEFAN INST,YU-61000 LJUBLJANA,SLOVENIA. UNIV HELSINKI,HIGH ENERGY PHYS RES INST,SF-00170 HELSINKI 17,FINLAND. UNIV MILAN,DIPARTIMENTO FIS,I-20133 MILAN,ITALY. UNIV STOCKHOLM,INST PHYS,S-11346 STOCKHOLM,SWEDEN. UNIV TRIESTE,DIPARTIMENTO FIS,I-34127 TRIESTE,ITALY. CERN,CH-1211 GENEVA 23,SWITZERLAND. RUTHERFORD APPLETON LAB,DIDCOT OX11 0QX,OXON,ENGLAND. UNIV KARLSRUHE,INST EXPTL PHYS,W-7500 KARLSRUHE 1,GERMANY. CAS,INST PHYS,DIV HIGH ENERGY PHYS,FZU,CS-18040 PRAGUE 8,CZECHOSLOVAKIA. UNIV LANCASTER,SCH PHYS & MAT,LANCASTER LA1 4YB,ENGLAND. CTR BRASILEIRO PESQUISAS FIS,BR-22290 RIO JANEIRO,BRAZIL. RP ABREU, P (reprint author), FOUL,IST,LIP,AY ELIAS GARCIA 14 1O,P-1000 LISBON,PORTUGAL. RI Dracos, Marcos/K-2335-2012; Hallgren, Allan/A-8963-2013; Botner, Olga/A-9110-2013; Zalewski, Piotr/H-7335-2013; Marti-Garcia, Salvador/F-3085-2011; Vaz, Pedro/K-2464-2013; Monge, Maria Roberta/G-9127-2012; Ridky, Jan/H-6184-2014; Zukanovich Funchal, Renata/C-5829-2013; Tome, Bernardo/J-4410-2013; Fernandez, Ester/K-9734-2014; Pimenta, Mario/M-1741-2013; Verlato, Marco/J-4604-2012; de Groot, Nicolo/A-2675-2009; Katsanevas, Stavros/A-4297-2011; Ruiz, Alberto/E-4473-2011; branchini, paolo/A-4857-2011; Shellard, Ronald/G-4825-2012; Schulze, Bruno/B-7599-2008; Petrolini, Alessandro/H-3782-2011; Torassa, Ezio/I-1788-2012; Giacomelli, Paolo/B-8076-2009; Fruhwirth, Rudolf/H-2529-2012; Andreazza, Attilio/E-5642-2011; Gomez Cadenas, Juan Jose/L-2003-2014; Ragazzi, Stefano/D-2463-2009; Roditi, Itzhak/O-7448-2014; Zuniga, Juan/P-4385-2014; Michelotto, Michele/A-9571-2013; Matorras, Francisco/I-4983-2015; Ferrer, Antonio/H-2942-2015; Rovelli, Tiziano/K-4432-2015; Fernandez-Alonso, Mercedes/F-2557-2016; Lozano-Bahilo, Julio/F-4881-2016; Olshevskiy, Alexander/I-1580-2016; Paganoni, Marco/A-4235-2016; Contreras Gonzalez, Jose Luis/K-7255-2014; Hernandez-Rey, Juan Jose/N-5955-2014; Abreu, Pedro/L-2220-2014; Barao, Fernando/O-2357-2016; Barrio, Juan/L-3227-2014; Zaitsev, Alexandre/B-8989-2017; OI Dracos, Marcos/0000-0003-0514-193X; Vaz, Pedro/0000-0002-7186-2359; Monge, Maria Roberta/0000-0003-1633-3195; Ridky, Jan/0000-0001-6697-1393; Zukanovich Funchal, Renata/0000-0001-6749-0022; Tome, Bernardo/0000-0002-7564-8392; Pimenta, Mario/0000-0002-2590-0908; Verlato, Marco/0000-0003-1967-7655; Ruiz, Alberto/0000-0002-3639-0368; Shellard, Ronald/0000-0002-2983-1815; Schulze, Bruno/0000-0002-3325-5785; Petrolini, Alessandro/0000-0003-0222-7594; Andreazza, Attilio/0000-0001-5161-5759; Gomez Cadenas, Juan Jose/0000-0002-8224-7714; Ragazzi, Stefano/0000-0001-8219-2074; Roditi, Itzhak/0000-0003-2363-5626; Zuniga, Juan/0000-0002-1041-6451; Michelotto, Michele/0000-0001-6644-987X; Matorras, Francisco/0000-0003-4295-5668; Ferrer, Antonio/0000-0003-0532-711X; Rovelli, Tiziano/0000-0002-9746-4842; Fernandez-Alonso, Mercedes/0000-0002-1311-5275; Lozano-Bahilo, Julio/0000-0003-0613-140X; Olshevskiy, Alexander/0000-0002-8902-1793; Paganoni, Marco/0000-0003-2461-275X; Contreras Gonzalez, Jose Luis/0000-0001-7282-2394; Hernandez-Rey, Juan Jose/0000-0002-1527-7200; Abreu, Pedro/0000-0002-9973-7314; Barao, Fernando/0000-0002-8346-9941; Barrio, Juan/0000-0002-0965-0259; Zaitsev, Alexandre/0000-0002-4961-8368; Matteuzzi, Clara/0000-0002-4047-4521; DE MIN, ALBERTO/0000-0002-8130-9389; Demaria, Natale/0000-0003-0743-9465; Bonesini, Maurizio/0000-0001-5119-1896; Sannino, Mario/0000-0001-7700-8383; De Lotto, Barbara/0000-0003-3624-4480; Tabarelli de Fatis, Tommaso/0000-0001-6262-4685; Lacasta, Carlos/0000-0002-2623-6252; Torassa, Ezio/0000-0003-2321-0599 NR 17 TC 17 Z9 17 U1 0 U2 9 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 MAR 25 PY 1993 VL 302 IS 2-3 BP 356 EP 368 DI 10.1016/0370-2693(93)90409-B PG 13 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KT530 UT WOS:A1993KT53000040 ER PT J AU CREIGHTON, JR BANSENAUER, BA AF CREIGHTON, JR BANSENAUER, BA TI THE SURFACE-CHEMISTRY AND KINETICS OF GAAS ATOMIC LAYER EPITAXY SO THIN SOLID FILMS LA English DT Article ID GAAS(100) SURFACES; BEAM EPITAXY; TRIMETHYLGALLIUM; GROWTH; MECHANISM; SPECTROSCOPY; DECOMPOSITION; CHEMISORPTION; DEPOSITION; GAAS(001) AB We discuss the chemical and kinetic aspects of GaAs atomic layer epitaxy (ALE). Explanations of the stoichiometry problems of GaAs ALE are proposed. We review the proposed ALE mechanisms that deal with trimethylgallium exposure. Results conclusively invalidate the selective adsorption ALE mechanism. Kinetic results indicate that the GaAs surface is covered with CH, groups during typical ALE conditions, as proposed by the adsorbate inhibition mechanism. Measurements of excess gallium deposition at typical ALE partial pressures are in good agreement with predictions of a unimolecular reaction mechanism using kinetic parameters determined by surface science techniques. Two simple ALE kinetic models based on unimolecular surface reaction mechanisms are constructed and the predictions are in good agreement with atmospheric pressure ALE results. The possible role of the flux balance mechanism is discussed. RP CREIGHTON, JR (reprint author), SANDIA NATL LABS, DIV 1126, ALBUQUERQUE, NM 87185 USA. NR 44 TC 14 Z9 14 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD MAR 25 PY 1993 VL 225 IS 1-2 BP 17 EP 25 DI 10.1016/0040-6090(93)90120-E PG 9 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA KV102 UT WOS:A1993KV10200005 ER PT J AU MAHAJAN, A IRBY, J KINOSKY, D QIAN, R THOMAS, S BANERJEE, S TASCH, A PICRAUX, T AF MAHAJAN, A IRBY, J KINOSKY, D QIAN, R THOMAS, S BANERJEE, S TASCH, A PICRAUX, T TI SI ATOMIC LAYER EPITAXY BASED ON SI2H6 AND REMOTE HE PLASMA BOMBARDMENT SO THIN SOLID FILMS LA English DT Article ID HYDROGEN; SURFACE; SI(100) AB Atomic layer epitaxy (ALE) of Si has been demonstrated by using remote He plasma low energy ion bombardment to desorb H from an H-passivated Si(100) surface at low temperatures and subsequently chemisorbing Si2H6 on the surface in a self-limiting fashion. Si substrates were prepared using an RCA clean followed by a dilute HF dip to provide a clean, dihydride-terminated (1 x 1) surface, and were loaded into a remote plasma chemical vapor deposition system in which the substrate is downstream from an r.f. noble gas (He or Ar) glow discharge in order to minimize plasma damage. An in situ remote H plasma clean at 250-degrees-C for 45 min was used to remove surface 0 and C and to provide an alternating monohydride and dihydride termination, as evidenced by a (3 x 1) reflection high energy electron diffraction (RHEED) pattern. It was found necessary to desorb the H from the Si surface to create adsorption sites for Si- bearing species such as Si2H6. Remote He plasma bombardment for 1-3 min was investigated over a range of temperature (250-degrees-C-410-degrees-C), pressures (50-400 mTorr) and r.f. powers (6-30 W) in order to desorb the H and to convert the (3 x 1) RHEED pattern to a (2 x 1) pattern which is characteristic of either a monohydride termination or a bare Si surface. It was found that as He pressures and r.f. powers are raised the plasma potential and mean free paths are reduced, leading to lower He bombardment energies but higher fluxes. Optimal He bombardment parameters were determined to be 30 W at 100 mTorr process pressure at 400-degrees-C for 1-3 min. He was found to be more effective than Ar bombardment because of the closer match of the He and H masses compared with that between Ar and H. Monte Carlo TRIM simulations of He and Ar bombardment of H-terminated Si surfaces were performed to validate this hypothesis and to predict that approximately 3 surface H atoms were displaced by the incident He atoms, with no bulk Si atom displacement for He energies in the range 15-60 eV. The He bombardment cycles were followed by Si2H6 dosing over a range of partial pressures (from 10(-7) Torr to 1.67 mTorr), temperatures (250-degrees-C-400-degrees-C) and times (from 20 s to 3 min) without plasma excitation. because it is believed that Si2H6 can chemisorb in a self-limiting fashion on a bare Si surface as two silyl (SiH3) species, presumably leading to a H-terminated surface once again. The Si2H6 dosing pressures and times corresponded to saturation dosing (about 10(6) langmuirs). Alternate Si2H6 dosing and He low energy ion bombardment cycles (about 100-200) were performed to confirm the ALE mode of growth. It was found that the growth per cycle saturates with long Si2H6 dosing at a level which increases slightly with He bombardment time. At 400-degrees-C, for 2 min He bombardment at 100 mTorr and 30 W, the growth per cycle saturates at about 0.1 monolayers cycle-1, while for 3 min He bombardment the Si growth saturates at about 0.15 monolayers cycle-1. It was also confirmed that the growth is achieved only by using alternate He bombardment and Si2H6 dosing. He bombardment alone for a comparable time (3 min x 100 cycles) causes a negligible change in the Si film thickness (less than 5 angstrom). Similarly, thermal growth using Si2H6 under these conditions for (3 min x 100 cycles) causes negligible deposition (less than 5 angstrom). C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP MAHAJAN, A (reprint author), UNIV TEXAS,DEPT ELECT & COMP ENGN,ENS415,AUSTIN,TX 78712, USA. NR 8 TC 17 Z9 17 U1 0 U2 7 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 MAR 25 PY 1993 VL 225 IS 1-2 BP 177 EP 182 DI 10.1016/0040-6090(93)90151-E PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA KV102 UT WOS:A1993KV10200036 ER PT J AU SUMAKERIS, J SITAR, Z AILEYTRENT, KS MORE, KL DAVIS, RF AF SUMAKERIS, J SITAR, Z AILEYTRENT, KS MORE, KL DAVIS, RF TI LAYER-BY-LAYER EPITAXIAL-GROWTH OF GAN AT LOW-TEMPERATURES SO THIN SOLID FILMS LA English DT Article ID SELF-LIMITING MECHANISM; MOLECULAR-BEAM EPITAXY; GALLIUM NITRIDE; THIN-FILMS; GAAS; SILICON AB GaN films have been grown on (0001)Si SiC substrates from triethylgallium and ammonia sources using a self-terminating atomic layer epitaxy method, as well as a layer-by-layer technique and a novel reactor design employing hot filaments to decompose the ammonia. The material properties and growth process were strongly dependent on the temperature and exposure time. GaN grew in a self-terminating fashion for temperatures below 120-degrees-C but the films were amorphous. Above this temperature, the films were deposited in a layer-by-layer process giving single-crystal material in the 250-350-degrees-C range. Characterization of the films was conducted using reflection high energy electron diffraction, single-crystal X-ray diffraction, ellipsometry and high resolution transmission electron microscopy. C1 OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831. RP SUMAKERIS, J (reprint author), N CAROLINA STATE UNIV,DEPT MAT SCI & ENGN,BOX 7907,RIDDICK HALL,RALEIGH,NC 27695, USA. RI Davis, Robert/A-9376-2011; More, Karren/A-8097-2016 OI Davis, Robert/0000-0002-4437-0885; More, Karren/0000-0001-5223-9097 NR 20 TC 28 Z9 28 U1 0 U2 6 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 MAR 25 PY 1993 VL 225 IS 1-2 BP 244 EP 249 DI 10.1016/0040-6090(93)90163-J PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA KV102 UT WOS:A1993KV10200048 ER PT J AU JELINEK, R STEIN, A OZIN, GA AF JELINEK, R STEIN, A OZIN, GA TI BR-81 AND CL-35 NMR INVESTIGATION OF SODIUM, SILVER, HALO SODALITE SEMICONDUCTOR SUPRALATTICES SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID SOLID-STATE NMR; QUANTUM DOTS; MAS-NMR; ZEOLITES; NUCLEI; RELAXATION AB Br-81 and Cl-35 NMR yields, respectively, bromide and chloride site-specific information pertinent to the structural and electronic properties of Na8-n-pAgnX2-p-sodalite, semiconductor cluster supralattices, where X = Br, Cl; 0 less-than-or-equal-to n less-than-or-equal-to 8; 0 less-than-or-equal-to p less-than-or-equal-to 2. The Br-81 and Cl-35 MAS chemical shifts and line shapes observed for encapsulated Na4X and Ag4X clusters within the sodalite cavities provide insight into the nature of the intracluster bonding (ionic-covalent character) and the extent of intercavity coupling. Substantial nuclear shielding is observed for encapsulated Ag4X clusters in sodalite materials with high loading of Ag4Br clusters, whereas no NMR signal is detected from silver-bromide clusters isolated within sodalite lattices. Spin-lattice and spin-spin relaxation measurements yield information on intracavity coupling and motion within the sodalite cages. The results enable one to explore the transition from isolated clusters to an expanded Ag4X supralattice, through the compositional and temperature dependence of the NMR spectra of the sodalite halide anions. C1 UNIV TORONTO,LASH MILLER CHEM LABS,ADV ZEOLITE MAT SCI RES GRP,80 ST GEORGE ST,TORONTO M5S 1A1,ONTARIO,CANADA. LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. OI jelinek, raz/0000-0002-0336-1384 NR 26 TC 15 Z9 16 U1 0 U2 2 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 MAR 24 PY 1993 VL 115 IS 6 BP 2390 EP 2396 DI 10.1021/ja00059a038 PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA KU902 UT WOS:A1993KU90200038 ER PT J AU LIU, YP LYNCH, GC TRUONG, TN LU, DH TRUHLAR, DG GARRETT, BC AF LIU, YP LYNCH, GC TRUONG, TN LU, DH TRUHLAR, DG GARRETT, BC TI MOLECULAR MODELING OF THE KINETIC ISOTOPE EFFECT FOR THE [1,5] SIGMATROPIC REARRANGEMENT OF CIS-1,3-PENTADIENE SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TRANSITION-STATE-THEORY; POTENTIAL-ENERGY SURFACES; 1,5-SIGMATROPIC HYDROGEN SHIFTS; VIBRATIONALLY ADIABATIC MODELS; DIRECT DYNAMICS CALCULATIONS; GROUND-STATES; SEMIEMPIRICAL METHODS; CHEMICAL-REACTIONS; PARAMETERS; ABINITIO AB The primary kinetic isotope effect for the [1,5] sigmatropic rearrangement reaction of cis-1,3-pentadiene is studied by the direct dynamics method. The calculations are carried out with the computer code MORATE, which combines the semiempirical molecular orbital package, MOPAC, and the polyatomic dynamics code, POLYRATE, developed previously by our research group. Dynamics calculations are based on canonical variational transition-state theory including multidimensional tunneling corrections. The force field is obtained by molecular orbital theory with the AM1, PM3, and MINDO/3 parameterizations. The kinetic isotope effects calculated with the MINDO/3 and PM3 Hamiltonians agree with those calculated by AM1 within 13%, and the latter agree with experiment within 13%. The tunneling contributions to the kinetic isotope effects are analyzed, and the nature of the vibrationally assisted tunneling process is discussed. General features of the dynamics from all three parameterizations are similar, and the quantitative differences in the predictions of the three calculations can be understood in terms of global characteristics of the potential energy functions that they predict. C1 UNIV MINNESOTA, DEPT CHEM, MINNEAPOLIS, MN 55455 USA. UNIV MINNESOTA, INST SUPERCOMP, MINNEAPOLIS, MN 55455 USA. PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. RI Garrett, Bruce/F-8516-2011; Truhlar, Donald/G-7076-2015 OI Truhlar, Donald/0000-0002-7742-7294 NR 66 TC 670 Z9 684 U1 4 U2 37 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAR 24 PY 1993 VL 115 IS 6 BP 2408 EP 2415 DI 10.1021/ja00059a041 PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA KU902 UT WOS:A1993KU90200041 ER PT J AU SMITH, DA REYNOLDS, DN WOO, LK AF SMITH, DA REYNOLDS, DN WOO, LK TI CYCLOPROPANATION CATALYZED BY OSMIUM PORPHYRIN COMPLEXES SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Note ID TRANSITION-METAL; OLEFINS; RHODIUM(III)PORPHYRINS; CHEMISTRY C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 21 TC 87 Z9 88 U1 0 U2 3 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 MAR 24 PY 1993 VL 115 IS 6 BP 2511 EP 2513 DI 10.1021/ja00059a059 PG 3 WC Chemistry, Multidisciplinary SC Chemistry GA KU902 UT WOS:A1993KU90200059 ER PT J AU PANG, Y PETRICH, SA YOUNG, VG GORDON, MS BARTON, TJ AF PANG, Y PETRICH, SA YOUNG, VG GORDON, MS BARTON, TJ TI SYNTHESES AND STRUCTURE OF 8-MEMBERED, 7-MEMBERED, AND 6-MEMBERED SILACYCLOALLENES SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Note C1 IOWA STATE UNIV SCI & TECHNOL, US DOE, AMES LAB, AMES, IA 50011 USA. IOWA STATE UNIV SCI & TECHNOL, DEPT CHEM, AMES, IA 50011 USA. NR 11 TC 41 Z9 41 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAR 24 PY 1993 VL 115 IS 6 BP 2534 EP 2536 DI 10.1021/ja00059a073 PG 3 WC Chemistry, Multidisciplinary SC Chemistry GA KU902 UT WOS:A1993KU90200073 ER PT J AU VONROEDERN, B AF VONROEDERN, B TI SHORTFALL OF DEFECT MODELS FOR AMORPHOUS-SILICON SOLAR-CELL PERFORMANCE SO APPLIED PHYSICS LETTERS LA English DT Article AB It is suggested that the prevailing models for the Staebler-Wronski effect are incorrect because they ignore the effects of charged dangling bonds. The degradation behavior of material parameters such as photoconductivity or midgap defect densities does not allow us to predict either the magnitude or the kinetic behavior of solar cell degradation. RP VONROEDERN, B (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 14 TC 13 Z9 13 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 MAR 22 PY 1993 VL 62 IS 12 BP 1368 EP 1369 DI 10.1063/1.108681 PG 2 WC Physics, Applied SC Physics GA KT419 UT WOS:A1993KT41900020 ER PT J AU MORSE, JD MARIELLA, RP ADKISSON, JW ANDERSON, GD HARRIS, JS DUTTON, RW AF MORSE, JD MARIELLA, RP ADKISSON, JW ANDERSON, GD HARRIS, JS DUTTON, RW TI PICOSECOND PHOTOCONDUCTIVITY IN POLYCRYSTALLINE GALLIUM-ARSENIDE GROWN BY MOLECULAR-BEAM EPITAXY SO APPLIED PHYSICS LETTERS LA English DT Article ID FILMS AB Picosecond photoconductivity in polycrystalline gallium arsenide (GaAs) layers grown on silicon dioxide by molecular beam epitaxy has been investigated. Photocurrent transient responses having full width at half-maximum of approximately 2.2 ps were measured by photoconductive sampling techniques. Interdigitated metal-semiconductor-metal photodiodes have been fabricated from the polycrystalline GaAs with 1.5- and 5-mum electrode spacing. The corresponding responsivities measured are 40 mA/W and 0.15 A/W, respectively, at 10 V/mum bias voltage and 820-nm wavelength. The corresponding effective mobility of this material is estimated to be mu(eff) approximately 80 cm2/V s, making this photodetector competitive with alternative technologies for ultrahigh speed applications. C1 STANFORD UNIV,DEPT ELECT ENGN,STANFORD,CA 94305. RP MORSE, JD (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,L-156,LIVERMORE,CA 94550, USA. NR 10 TC 0 Z9 0 U1 1 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 MAR 22 PY 1993 VL 62 IS 12 BP 1382 EP 1384 DI 10.1063/1.108686 PG 3 WC Physics, Applied SC Physics GA KT419 UT WOS:A1993KT41900025 ER PT J AU BLOCKI, J SHI, JJ SWIATECKI, WJ AF BLOCKI, J SHI, JJ SWIATECKI, WJ TI ORDER, CHAOS AND NUCLEAR-DYNAMICS SO NUCLEAR PHYSICS A LA English DT Article ID QUANTUM CHAOS; MODEL; RESEPARATION; COALESCENCE; COLLISIONS; SYSTEMS; FUSION AB The relation between the order-to-chaos transition in the dynamics of independent classical particles in a container, and the transition from an elastic to a dissipative response of the container to shape changes, is studied by means of computer simulations. The validity of the wall formula for energy dissipation is confirmed in the case of containers whose surfaces are rippled according to Legendre polynomials P3, P4, P5, P6, in which case the particle trajectories are largely chaotic, as revealed by Poincare sections in phase space. The opposite limit of an elastic response is illustrated by means of spheroidal containers of various eccentricities, for which the particle trajectories are integrable and the phase space is foliated by tori. Fission-like deformations are also considered, for which the response of the container changes from elastic to dissipative with increasing deformation. Idealized giant-dipole oscillations of the gas are studied for spherical as well as deformed containers. A generalization of the wall formula valid for long times (i.e., for arbitrarily large excitations of the gas) is constructed. The principal lesson of these studies is that a gas of independent particles in a time-dependent container does not behave at all like a gas. C1 LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. INST NUCL STUDIES,PL-05400 OTWOCK,POLAND. INST ATOM ENERGY,BEIJING,PEOPLES R CHINA. NR 38 TC 58 Z9 58 U1 0 U2 0 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 MAR 22 PY 1993 VL 554 IS 3 BP 387 EP 412 DI 10.1016/0375-9474(93)90227-O PG 26 WC Physics, Nuclear SC Physics GA KW270 UT WOS:A1993KW27000003 ER PT J AU LEE, IY XIE, H BAKTASH, C GAO, WB GARRETT, JD JOHNSON, NR MCGOWAN, FK WYSS, R AF LEE, IY XIE, H BAKTASH, C GAO, WB GARRETT, JD JOHNSON, NR MCGOWAN, FK WYSS, R TI LIFETIME MEASUREMENTS FOR CONTINUUM GAMMA-RAYS IN YB-164 AND HF-170 SO NUCLEAR PHYSICS A LA English DT Article DE TE-130(CA-44, 4N), E=195 MEV; SN-124(CA-44, 4N), E=189 MEV; MEASURED GAMMA-GAMMA-COIN, GAMMA-GAMMA(THETA); YB-164, HF-170 DEDUCED CONTINUUM STATES, T1/2; ENRICHED TARGETS, ARRAY OF COMPTON SUPPRESSED GE-DETECTORS ID HIGH-SPIN STATES; NUCLEI; BANDS AB Lifetimes of states associated with the ridges in the E(gamma)-E(gamma) correlation spectrum of 164Yb and 170Hf were measured by the Doppler-shift attenuation method. The results indicate a reduction of the quadrupole collectivity associated with gamma-rays with energy from 0.7 to 0.9 MeV and an enhancement of collectivity for those above 0.9 MeV. The reduced and the enhanced collectivity can be understood as rotationally-induced modifications of the occupation of high-j orbitals originating from below and above the Fermi surface, respectively. The effect of rotational damping on the lifetimes of continuum states is also discussed. C1 OAK RIDGE NATL LAB,DIV PHYS,BLDG 6000,MAIL STOP 6371,BOX 2008,OAK RIDGE,TN 37831. VANDERBILT UNIV,NASHVILLE,TN 37235. JOINT INST HEAVY ION RES,OAK RIDGE,TN 37831. NR 22 TC 5 Z9 5 U1 0 U2 0 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 MAR 22 PY 1993 VL 554 IS 3 BP 485 EP 492 DI 10.1016/0375-9474(93)90231-L PG 8 WC Physics, Nuclear SC Physics GA KW270 UT WOS:A1993KW27000007 ER PT J AU FRABETTI, PL CHEUNG, HWK CUMALAT, JP DALLAPICCOLA, C GINKEL, JF GREENE, SV JOHNS, WE NEHRING, MS BUTLER, JN CIHANGIR, S GAINES, I GARREN, L GARBINCIUS, PH GOURLAY, SA HARDING, DJ KASPER, P KREYMER, A LEBRUN, P SHUKLA, S BIANCO, S FABBRI, FL SARWAR, S ZALLO, A CULBERTSON, R GARDNER, RW GREENE, R WISS, J ALIMONTI, G BELLINI, G CACCIANIGA, B CINQUINI, L DICORATO, M GIAMMARCHI, M INZANI, P LEVERARO, F MALVEZZI, S MENASCE, D MERONI, E MORONI, L PEDRINI, D PERASSO, L SALA, A SALA, S TORRETTA, D VITTONE, M BUCHHOLZ, D CLAES, D GOBBI, B OREILLY, B BISHOP, JM CASON, NM KENNEDY, CJ KIM, GN LIN, TF MANNEL, EJ PUSELJIC, DL RUCHTI, RC SHEPHARD, WD SWIATEK, JA WU, ZY ARENA, V BOCA, G CASTOLDI, C DIAFERIA, R GIANINI, G RATTI, SP RICCARDI, C VITULO, P LOPEZ, A GRIM, GP PAOLONE, VS YAGER, PM WILSON, JR SHELDON, PD DAVENPORT, F FILASETTA, JF BLACKETT, GR PISHARODY, M HANDLER, T CHEON, BG KANG, JS KIM, KY AF FRABETTI, PL CHEUNG, HWK CUMALAT, JP DALLAPICCOLA, C GINKEL, JF GREENE, SV JOHNS, WE NEHRING, MS BUTLER, JN CIHANGIR, S GAINES, I GARREN, L GARBINCIUS, PH GOURLAY, SA HARDING, DJ KASPER, P KREYMER, A LEBRUN, P SHUKLA, S BIANCO, S FABBRI, FL SARWAR, S ZALLO, A CULBERTSON, R GARDNER, RW GREENE, R WISS, J ALIMONTI, G BELLINI, G CACCIANIGA, B CINQUINI, L DICORATO, M GIAMMARCHI, M INZANI, P LEVERARO, F MALVEZZI, S MENASCE, D MERONI, E MORONI, L PEDRINI, D PERASSO, L SALA, A SALA, S TORRETTA, D VITTONE, M BUCHHOLZ, D CLAES, D GOBBI, B OREILLY, B BISHOP, JM CASON, NM KENNEDY, CJ KIM, GN LIN, TF MANNEL, EJ PUSELJIC, DL RUCHTI, RC SHEPHARD, WD SWIATEK, JA WU, ZY ARENA, V BOCA, G CASTOLDI, C DIAFERIA, R GIANINI, G RATTI, SP RICCARDI, C VITULO, P LOPEZ, A GRIM, GP PAOLONE, VS YAGER, PM WILSON, JR SHELDON, PD DAVENPORT, F FILASETTA, JF BLACKETT, GR PISHARODY, M HANDLER, T CHEON, BG KANG, JS KIM, KY TI MEASUREMENT OF THE LAMBDA-C+ LIFETIME SO PHYSICAL REVIEW LETTERS LA English DT Article AB A precise measurement of the LAMBDA(c)+ lifetime using approximately 1340 fully reconstructed LAMBDA(c)+ --> pK-pi+ and charge conjugate decays is presented. The data were accumulated by the Fermilab high energy photoproduction experiment E687. The lifetime of the LAMBDA(c)+ is measured to be 0.215+/-0.016+/-0.008 ps. C1 IST NAZL FIS NUCL,I-40126 BOLOGNA,ITALY. UNIV COLORADO,BOULDER,CO 80309. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. IST NAZL FIS NUCL,LAB NAZL FRASCATI,I-00044 FRASCATI,ITALY. IST NAZL FIS NUCL,I-20133 MILAN,ITALY. UNIV MILAN,DIPARTIMENTO FIS,I-20133 MILAN,ITALY. NORTHWESTERN UNIV,EVANSTON,IL 60208. UNIV NOTRE DAME,NOTRE DAME,IN 46556. IST NAZL FIS NUCL,I-27100 PAVIA,ITALY. UNIV PAVIA,DIPARTIMENTO FIS,I-27100 PAVIA,ITALY. UNIV PUERTO RICO,MAYAGUEZ,PR 00708. UNIV CALIF DAVIS,DAVIS,CA 95616. UNIV S CAROLINA,COLUMBIA,SC 29208. VANDERBILT UNIV,NASHVILLE,TN 37235. UNIV N CAROLINA,ASHEVILLE,NC 28804. NO KENTUCKY UNIV,HIGHLAND HTS,KY 41076. UNIV TENNESSEE,KNOXVILLE,TN 37996. KOREA UNIV,SEOUL 136701,SOUTH KOREA. RP FRABETTI, PL (reprint author), UNIV BOLOGNA,DIPARTIMENTO FIS,I-40126 BOLOGNA,ITALY. NR 6 TC 18 Z9 18 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 22 PY 1993 VL 70 IS 12 BP 1755 EP 1758 DI 10.1103/PhysRevLett.70.1755 PG 4 WC Physics, Multidisciplinary SC Physics GA KT367 UT WOS:A1993KT36700006 ER PT J AU BARRETTE, J BELLWIED, R BRAUNMUNZINGER, P CLELAND, WE CORMIER, T DADUSC, G DAVID, G DEE, J DIEBOLD, GE DIETZSCH, O DUEK, E FATYGA, M FOX, D GREENE, SV GERMANI, JV HALL, JR HEMMICK, TK HERRMANN, N HOGUE, RW HONG, B JAYANANDA, K KRAUS, D KUMAR, BS LACASSE, R LISSAUER, D LLOPE, WJ LUDLAM, TW MAJKA, R MAKOWIECKI, D MARK, SK MITCHELL, JT MUTHUSWAMY, M OBRIEN, E PRUNEAU, C ROTONDO, FS SANDWEISS, J DASILVA, NC SIMONGILLO, J SLAUGHTER, J SONNADARA, U STACHEL, J TAKAI, H TAKAGUI, EM THROWE, TG WATERS, L WINTER, C WOLF, K WOLFE, D WOODY, CL XU, N ZHANG, Y ZHANG, Z ZOU, C AF BARRETTE, J BELLWIED, R BRAUNMUNZINGER, P CLELAND, WE CORMIER, T DADUSC, G DAVID, G DEE, J DIEBOLD, GE DIETZSCH, O DUEK, E FATYGA, M FOX, D GREENE, SV GERMANI, JV HALL, JR HEMMICK, TK HERRMANN, N HOGUE, RW HONG, B JAYANANDA, K KRAUS, D KUMAR, BS LACASSE, R LISSAUER, D LLOPE, WJ LUDLAM, TW MAJKA, R MAKOWIECKI, D MARK, SK MITCHELL, JT MUTHUSWAMY, M OBRIEN, E PRUNEAU, C ROTONDO, FS SANDWEISS, J DASILVA, NC SIMONGILLO, J SLAUGHTER, J SONNADARA, U STACHEL, J TAKAI, H TAKAGUI, EM THROWE, TG WATERS, L WINTER, C WOLF, K WOLFE, D WOODY, CL XU, N ZHANG, Y ZHANG, Z ZOU, C TI ANTIPROTON PRODUCTION IN RELATIVISTIC SI-NUCLEUS COLLISIONS SO PHYSICAL REVIEW LETTERS LA English DT Article ID HEAVY-ION COLLISIONS; PBAR AB We have measured antiproton production cross sections as functions of centrality in collisions of 14.6 GeV/c per nucleon Si-28 ions with targets of Al, Cu, and Pb. For all targets, the antiproton yields increase linearly with the number of projectile nucleons that have interacted, and show little target dependence. We discuss the implications of this result on the production and absorption of antiprotons within the nuclear medium. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV NEW MEXICO,ALBUQUERQUE,NM 87131. UNIV PITTSBURGH,PITTSBURGH,PA 15260. SUNY STONY BROOK,STONY BROOK,NY 11794. UNIV SAO PAULO,SAO PAULO,BRAZIL. TEXAS A&M UNIV SYST,COLL STN,TX 77843. YALE UNIV,NEW HAVEN,CT 06511. RP BARRETTE, J (reprint author), MCGILL UNIV,MONTREAL H3A 2T8,QUEBEC,CANADA. RI Takai, Helio/C-3301-2012; Duek, Eliana/J-2499-2012; OI Takai, Helio/0000-0001-9253-8307; Sonnadara, Upul/0000-0001-7862-2537 NR 21 TC 21 Z9 21 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 22 PY 1993 VL 70 IS 12 BP 1763 EP 1766 DI 10.1103/PhysRevLett.70.1763 PG 4 WC Physics, Multidisciplinary SC Physics GA KT367 UT WOS:A1993KT36700008 ER PT J AU DIMONTE, G REMINGTON, B AF DIMONTE, G REMINGTON, B TI RICHTMYER-MESHKOV EXPERIMENTS ON THE NOVA LASER AT HIGH COMPRESSION SO PHYSICAL REVIEW LETTERS LA English DT Article ID INTERFACE AB We investigate the shock induced Richtmyer-Meshkov instability at high compression using the Nova laser. The instability and shock characteristics are measured radiographically in planar two-fluid targets with Atwood number < 0. The growth of imposed interfacial perturbations eta = eta0sinkx agrees with linear theory if the pre- and postshock initial amplitudes are averaged. When keta is similar to 2, the fundamental mode saturates and harmonics emerge producing a slowly developing bubble and spike. RP DIMONTE, G (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 16 TC 60 Z9 61 U1 1 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 MAR 22 PY 1993 VL 70 IS 12 BP 1806 EP 1809 DI 10.1103/PhysRevLett.70.1806 PG 4 WC Physics, Multidisciplinary SC Physics GA KT367 UT WOS:A1993KT36700019 ER PT J AU LUCAS, CA WONG, GCL LORETTO, D AF LUCAS, CA WONG, GCL LORETTO, D TI STRUCTURAL TRANSITIONS OF THE CAF2/SI(111) INTERFACE SO PHYSICAL REVIEW LETTERS LA English DT Article ID SURFACE AB We have used x-ray reflectivity and transmission electron microscopy to study the CaF2/Si(111) interface. The results are consistent with a reconstructed two-layer CaF interface which can be transformed to a different structure simply by increasing the thickness of the CaF2 overlayer. We are able to reconcile previous measurements of the interface structure and gain insight into the rich variety of phenomena that may be observed at heteroepitaxial interfaces. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. RP LUCAS, CA (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720, USA. OI Lucas, Christopher/0000-0001-5743-3868 NR 19 TC 37 Z9 37 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 22 PY 1993 VL 70 IS 12 BP 1826 EP 1829 DI 10.1103/PhysRevLett.70.1826 PG 4 WC Physics, Multidisciplinary SC Physics GA KT367 UT WOS:A1993KT36700024 ER PT J AU KOGAN, VG LEDVIJ, M SIMONOV, AY CHO, JH JOHNSTON, DC AF KOGAN, VG LEDVIJ, M SIMONOV, AY CHO, JH JOHNSTON, DC TI ROLE OF VORTEX FLUCTUATIONS IN DETERMINING SUPERCONDUCTING PARAMETERS FROM MAGNETIZATION DATA FOR LAYERED SUPERCONDUCTORS SO PHYSICAL REVIEW LETTERS LA English DT Article ID PENETRATION DEPTH; HIGH-TC; REVERSIBLE MAGNETIZATION; TEMPERATURE; FIELD; BI2SR2CACU2O8; VORTICES; MODEL AB The fluctuations of vortices in Josephson-coupled layered superconductors are shown to have a profound effect on values of the temperature-dependent penetration depth, Ginzburg-Landau parameter, and upper critical field extracted from reversible magnetization data below the critical temperature. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. RP KOGAN, VG (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. RI Simonov, Andrei/C-1697-2015 OI Simonov, Andrei/0000-0001-6452-0214 NR 26 TC 147 Z9 147 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 22 PY 1993 VL 70 IS 12 BP 1870 EP 1873 DI 10.1103/PhysRevLett.70.1870 PG 4 WC Physics, Multidisciplinary SC Physics GA KT367 UT WOS:A1993KT36700035 ER PT J AU SABATANI, E TICIANELLI, E REDONDO, A RUBINSTEIN, I RISHPON, J GOTTESFELD, S AF SABATANI, E TICIANELLI, E REDONDO, A RUBINSTEIN, I RISHPON, J GOTTESFELD, S TI MORPHOLOGICAL EFFECTS IN CONDUCTING POLYMER-FILMS STUDIED BY COMBINED QCM AND SPECTROSCOPIC ELLIPSOMETRY SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF ON SCIENCE AND TECHNOLOGY OF SYNTHETIC METALS ( ICSM 92 ) CY AUG 12-18, 1992 CL GOTEBORG, SWEDEN AB This contribution describes our studies of electrochemically grown conducting polymer (CP) films. We used an instrumental system which enables simultaneous optical (ellipsometric) and microgravimetric (Quartz-Crystal-Microbalance) measurements in situ during CP film growth and during electrochemical cycling. Our paper reviews recent results obtained with this system in the study of films of polyaniline and of polypyrrole in aqueous systems which provides information on film growth mechanisms and on the dependence of film morphology on electrochemical growth conditions and postgrowth treatments. We describe recent measurements of morphological changes in electrochemically grown films of polyaniline induced by the application of electrochemical undoping-redoping cycles. RP SABATANI, E (reprint author), LOS ALAMOS NATL LAB,ELECTR RES GRP,LOS ALAMOS,NM 87545, USA. RI Ticianelli, Edson/D-1560-2012 OI Ticianelli, Edson/0000-0003-3432-2799 NR 6 TC 26 Z9 26 U1 0 U2 12 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 MAR 22 PY 1993 VL 55 IS 2-3 BP 1293 EP 1298 DI 10.1016/0379-6779(93)90240-W PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA LH620 UT WOS:A1993LH62000095 ER PT J AU KEADY, JJ RIDGWAY, ST AF KEADY, JJ RIDGWAY, ST TI THE IRC + 10216 CIRCUMSTELLAR ENVELOPE .3. INFRARED MOLECULAR LINE-PROFILES SO ASTROPHYSICAL JOURNAL LA English DT Article DE CIRCUMSTELLAR MATTER; INFRARED, STARS; LINE, PROFILES; STARS, INDIVIDUAL (IRC + 10216); STARS, MASS LOSS ID +10216 CIRCUMSTELLAR ENVELOPE; HIGH-RESOLUTION FOURIER; INFRARED-SPECTRUM; EVOLVED STARS; DIPOLE-MOMENT; MASS-LOSS; IRC+10216; BAND; INTENSITIES; EMISSION AB The 10 mum spectrum (780-1240 cm-1) has been surveyed with a resolution of 0.009 cm-1. Numerous molecular vibration-rotation transitions were detected in absorption by the circumstellar shell. Analysis of the line profiles by means of spectral synthesis from models revealed radial abundance ratio variations in some species. SiO is approximately uniformly mixed through the inner shell. SiH4 and NH3 are apparently produced in the region 10 to 40 R*, possibly by formation on grains. CS is very strongly depleted in the region 100-1000 R*, perhaps onto grains. From nondetection of H-2 the current mass-loss rate is constrained to be less than 4 x 10(-5) M. yr-1. Gathering evidence for a recent decline in the mass-loss rate is strengthened by analysis of the low-excitation heterodyne NH3 line observation, which indicates that the mass-loss rate may have been 2-3 x larger 1000 yr ago (material currently near 700 R*). C1 KITT PEAK NATL OBSERV, TUCSON, AZ 85726 USA. NATL OPT ASTRON OBSERV, TUCSON, AZ 85726 USA. RP KEADY, JJ (reprint author), LOS ALAMOS NATL LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. NR 64 TC 81 Z9 81 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 1993 VL 406 IS 1 BP 199 EP 214 DI 10.1086/172431 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KT453 UT WOS:A1993KT45300020 ER PT J AU BENNETT, DP RHIE, SH AF BENNETT, DP RHIE, SH TI COBES CONSTRAINTS ON THE GLOBAL MONOPOLE AND TEXTURE THEORIES OF COSMIC STRUCTURE FORMATION SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMIC MICROWAVE BACKGROUND; COSMOLOGY, THEORY; EARLY UNIVERSE; LARGE-SCALE STRUCTURE OF THE UNIVERSE ID COLD DARK MATTER; LARGE-SCALE STRUCTURE; FLUCTUATIONS; COSMOLOGY; COSMOGONY; ORIGIN AB We report on a calculation of large-scale anisotropy in the cosmic microwave background radiation in the global monopole and texture models for cosmic structure formation. We have evolved the six-component linear gravitational field along with the monopole or texture scalar fields numerically in an expanding universe and performed the Sachs-Wolfe integrals directly on the calculated gravitational fields. On scales >7-degrees, we find a Gaussian distribution with an approximately scale-invariant fluctuation spectrum. The DELTAT/T amplitude is a factor of 4-5 larger than the prediction of the standard CDM model with the same Hubble constant and density fluctuation normalization. The recently reported COBE-DMR results imply that global monopole and texture models require high bias factors or a large Hubble constant in contrast to standard CDM which requires very low H-0 and bias values. For H-0 = 70 km s-1 Mpc-1, we find that normalizing to the COBE results implies b8 congruent-to 3.3 +/- 1.5 (95% confidence level) for global monopoles and b8 congruent-to 3.4 +/- 1.6 (95% confidence level) for textures. If we restrict ourselves to the range of bias factors thought to be reasonable before the announcement of the COBE results, 1.5 less than or similar b8 less than or similar 2.5, then it is fair to conclude that global monopoles and textures are consistent with the COBE results and are a better fit than standard CDM. C1 UNIV CALIF BERKELEY,CTR PARTICLE ASTROPHYS,BERKELEY,CA 94720. RP BENNETT, DP (reprint author), LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550, USA. RI Bennett, David/O-2136-2013 OI Bennett, David/0000-0001-8043-8413 NR 24 TC 43 Z9 44 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 MAR 20 PY 1993 VL 406 IS 1 BP L7 EP L10 DI 10.1086/186773 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KT454 UT WOS:A1993KT45400002 ER PT J AU MARSHALL, JA BURCH, JL CHOUEIRI, EY KAWASHIMA, N AF MARSHALL, JA BURCH, JL CHOUEIRI, EY KAWASHIMA, N TI CIV EXPERIMENTS ON ATLAS-1 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CRITICAL IONIZATION VELOCITY; INJECTION AB A test of the Critical Ionization Velocity (CIV) theory was made with neutral xenon releases from the Space Experiments with Particle Accelerators (SEPAC) hollow cathode plasma contactor onboard the Shuttle Orbiter Atlantis during the ATLAS-1 mission. The gas velocity perpendicular to the Earth's magnetic field was essentially the orbital velocity (7.5 km/s), and thus it exceeded the CIV for xenon. The releases were observed with onboard instrumentation. A factor of 60 enhancement was seen in the Langmuir probe current. Calculations confirmed that release conditions generally satisfied criteria for CIV and predicted a maximum factor of 20 increase in plasma density. Thus, CIV effects were likely to have occurred during the ATLAS-1 experiments. C1 INST SPACE & ASTRONAUT SCI,SAGAMIHARA 229,JAPAN. PRINCETON UNIV,ELECT PROPULS & PLASMA DYNAM LAB,PRINCETON,NJ 08544. RP MARSHALL, JA (reprint author), SW RES INST,PO DRAWER 28510,SAN ANTONIO,TX 78228, USA. NR 19 TC 8 Z9 8 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 19 PY 1993 VL 20 IS 6 BP 499 EP 502 DI 10.1029/93GL00593 PG 4 WC Geosciences, Multidisciplinary SC Geology GA KU908 UT WOS:A1993KU90800022 ER PT J AU DING, D COMPTON, RN HAUFLER, RE KLOTS, CE AF DING, D COMPTON, RN HAUFLER, RE KLOTS, CE TI MULTIPHOTON IONIZATION OF C60 SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Letter ID THERMIONIC EMISSION; PHOTOELECTRON-SPECTROSCOPY; CARBON-ATOMS; BUCKMINSTERFULLERENE; ABSORPTION; CLUSTERS; FRAGMENTATION; PHOTOPHYSICS; TUNGSTEN; DECAY AB The multiphoton ionization photoelectron spectrum (MPI-PES) of C60 using pulsed lasers of nanosecond duration shows prompt electrons resulting from direct two-photon ionization, as well as a dominant low-energy delayed electron signal which follows an approximately thermal energy distribution with average energy epsilonBAR = 0.30 +/- 0.05 eV. The MPI-PES together with the mass spectrum at lambda = 193 nm suggests an important role of intersystem crossing from the singlet to triplet manifold of C60. MPI at lambda = 193 nm is believed to result from such intersystem crossing followed by one-photon ionization of triplet C60. Under this assumption, the photoionization cross section for C60 in the lowest triplet state is estimated to be (5.1 +/- 2.0) x 10(-17) cm-2. C1 OAK RIDGE NATL LAB,CHEM PHYS SECT,POB 2008,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. NR 38 TC 72 Z9 72 U1 1 U2 6 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 MAR 18 PY 1993 VL 97 IS 11 BP 2500 EP 2504 DI 10.1021/j100113a006 PG 5 WC Chemistry, Physical SC Chemistry GA KT613 UT WOS:A1993KT61300006 ER PT J AU RAMAKRISHNAN, V FINCH, JT GRAZIANO, V LEE, PL SWEET, RM AF RAMAKRISHNAN, V FINCH, JT GRAZIANO, V LEE, PL SWEET, RM TI CRYSTAL-STRUCTURE OF GLOBULAR DOMAIN OF HISTONE H5 AND ITS IMPLICATIONS FOR NUCLEOSOME BINDING SO NATURE LA English DT Article ID GENE ACTIVATOR PROTEIN; SYNCHROTRON RADIATION; ANOMALOUS DISPERSION; B-DNA; CHROMATIN; SEQUENCE; RESOLUTION; MODEL; H-5; MOLECULE AB The structure of GH5, the globular domain of the linker histone H5, has been solved to 2.5 angstrom resolution by multiwavelength anomalous diffraction on crystals of the selenomethionyl protein. The structure shows a striking similarity to the DNA-binding domain of the catabolite gene activator protein CAP, thereby providing a possible model for the binding of GH5 to DNA. C1 MRC,MOLEC BIOL LAB,CAMBRIDGE CB2 2QH,ENGLAND. RP RAMAKRISHNAN, V (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. OI Ramakrishnan, V/0000-0002-4699-2194 NR 47 TC 587 Z9 592 U1 1 U2 23 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD MAR 18 PY 1993 VL 362 IS 6417 BP 219 EP 223 DI 10.1038/362219a0 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KT026 UT WOS:A1993KT02600046 PM 8384699 ER PT J AU STURCHIO, NC DUNKLEY, PN SMITH, M AF STURCHIO, NC DUNKLEY, PN SMITH, M TI CLIMATE-DRIVEN VARIATIONS IN GEOTHERMAL ACTIVITY IN THE NORTHERN KENYA RIFT-VALLEY SO NATURE LA English DT Article ID LAKE-LEVEL FLUCTUATIONS; PLEISTOCENE AB HIGH-TEMPERATURE continental geothermal systems are primarily associated with volcanic activity at plate margins1. It has long been known that the activity of these geothermal systems is intermittent, and this is generally attributed to the effect of magmatic intrusions or fault motions. Recently, however, it has also been recognized2-4 that surface-water hydrology and climate variations can influence the evolution of individual silicic caldera-hosted geothermal systems, although it is difficult to judge the general importance of such effects in controlling the long-term behaviour of continental geothermal systems. Here we report uranium-series ages for the hydrothermal deposits of past geothermal activity from several Quaternary volcanic centres in the northern Kenya rift valley. We find that the ages correspond well to periods of high lake level within the rift, suggesting that the elevated water table and increased availability of meteoric water associated with more humid climates can promote greater transfer of heat and mass from deep, long-lived heat sources to the surface. C1 BRITISH GEOL SURVEY,KEYWORTH NG12 5GG,NOTTS,ENGLAND. RP STURCHIO, NC (reprint author), ARGONNE NATL LAB,GEOSCI CMT-205,ARGONNE,IL 60439, USA. NR 18 TC 36 Z9 36 U1 1 U2 5 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD MAR 18 PY 1993 VL 362 IS 6417 BP 233 EP 234 DI 10.1038/362233a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KT026 UT WOS:A1993KT02600051 ER PT J AU OHANDLEY, SF SANFORD, DG XU, R LESTER, CC HINGERTY, BE BROYDE, S KRUGH, TR AF OHANDLEY, SF SANFORD, DG XU, R LESTER, CC HINGERTY, BE BROYDE, S KRUGH, TR TI STRUCTURAL CHARACTERIZATION OF AN N-ACETYL-2-AMINOFLUORENE (AAF) MODIFIED DNA OLIGOMER BY NMR, ENERGY MINIMIZATION, AND MOLECULAR-DYNAMICS SO BIOCHEMISTRY LA English DT Article ID NUCLEAR MAGNETIC-RESONANCE; MUTATION HOT-SPOT; SINGLE ACETYLAMINOFLUORENE ADDUCT; PROTON COUPLING-CONSTANTS; MODIFIED OLIGODEOXYNUCLEOTIDES; MINOR-GROOVE; FORCE-FIELD; CONFORMATION; N-2-ACETYLAMINOFLUORENE; CARCINOGEN AB An N-acetyl-2-aminofluorene (AAF) modified deoxyoligonucleotide duplex, d(C1-C2-A3-C4-[AAF-G5]-C6-A7-C8-C9).d(G10-G11-T12-G13-C14-G15-T16-G17-G18), was studied by one- and two-dimensional NMR spectroscopy. Eight of the nine complementary nucleotides form Watson-Crick base pairs, as shown by NOEs between the guanine imino proton and cytosine amino protons for G-C base pairs or by an NOE between the thymine imino proton and adenine H2 proton for A.T base pairs. The AAF-G5 and C14 bases show no evidence of complementary hydrogen bond formation to each other. The AAF-G5 base adopts a syn conformation, as indicated by NOEs between the G5 imino proton and the A3-H3' and A3-H2'/H2'' protons and by NOEs between the fluorene-H1 proton of AAF and the G5-H1' or C6-H1' proton. The NOEs from the C4-H6 proton to C4 sugar protons are weak, and thus the glycosidic torsion angle in this nucleotide is not well defined by these NMR data. The remaining bases are in the anti conformation, as depicted by the relative magnitude of the H8/H6 to H2' NOEs when compared to the H8/H6 to H1' NOEs. The three base pairs on each end of the duplex exhibit NOEs characteristic of right-handed B-form DNA. Distance restraints obtained from NOESY data recorded at 32-degrees-C using a 100-ms mixing time were used in conformational searches by molecular mechanics energy minimization studies. The final, unrestrained, minimum-energy conformation was then used as input for an unrestrained molecular dynamics simulation. Chemical exchange cross peaks are observed, and thus the AAF-9-mer exists in more than a single conformation on the NMR time scale. The NMR data, however, indicate the presence of a predominant conformation (greater-than-or-equal-to 70%). The structure of the predominant conformation of the AAF-9-mer shows stacking of the fluorene moiety on an adjacent base pair, exhibiting features of the base-displacement [Grunberger, D., Nelson, J. H., et al. (1970) Proc. Natl. Acad. Sci. U.S.A. 66, 488-494] and insertion-denaturation models [Fuchs, R. P. P., & Daune, M. (1971) FEBS Lett. 14, 206-208], while the distal ring of the fluorene moiety protrudes into the minor groove. C1 UNIV ROCHESTER, DEPT CHEM, ROCHESTER, NY 14627 USA. NYU, DEPT CHEM, NEW YORK, NY 10003 USA. NYU, DEPT BIOL, NEW YORK, NY 10003 USA. OAK RIDGE NATL LAB, DIV HLTH & SAFETY RES, OAK RIDGE, TN 37831 USA. FU NCI NIH HHS [CA35251, CA28038]; NCRR NIH HHS [RR03317] NR 65 TC 129 Z9 130 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD MAR 16 PY 1993 VL 32 IS 10 BP 2481 EP 2497 DI 10.1021/bi00061a005 PG 17 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA KR819 UT WOS:A1993KR81900005 PM 8448107 ER PT J AU SUH, IH SEO, BI LEWIS, DE JENSEN, WP JACOBSON, RA AF SUH, IH SEO, BI LEWIS, DE JENSEN, WP JACOBSON, RA TI STRUCTURE OF THE P-NITROBENZOATE ESTER OF 3-ENDO-(P-METHOXYBENZYL)ISOBORNEOL SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article AB (1R,2R,3S,4R)-3-[(4-Methoxyphenyl)-methyl]-1,7,7-trimethylbicyclo[2.2.l]hept-2-yl 4-nitrobenzoate, C25H29NO5, M(r) = 423.5, orthorhombic, P2(1)2(1)2(1), a = 12.104 (3), b = 26.712 (5), c = 7.138 (i) angstrom, V = 2308.0 (8) angstrom3, Z = 4, D(x) = 1.22 g CM-3, lambda(Mo Kalpha) = 0.71073 angstrom, mu = 0.8 cm-1, F(000) = 904, room temperature, R = 0.065 for 1421 observed out of 1770 reflections. Maximum deviations from planarity of the two aromatic rings are 0.018 angstrom each; the dihedral angle formed by the two rings is 29.5 (3)-degrees, with a distance of closest approach of 3.827 (8) angstrom. The X-ray structure determination establishes the orientation of the aromatic rings and confirms the steric shielding of the Si face of the ester carbonyl group. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP SUH, IH (reprint author), S DAKOTA STATE UNIV,DEPT CHEM,BROOKINGS,SD 57007, USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD MAR 15 PY 1993 VL 49 BP 562 EP 565 DI 10.1107/S010827019200787X PN 3 PG 4 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA KU863 UT WOS:A1993KU86300056 ER PT J AU MA, CY BAYNE, CK AF MA, CY BAYNE, CK TI DIFFERENTIATION OF AROCLORS USING LINEAR DISCRIMINATION FOR ENVIRONMENTAL-SAMPLES ANALYZED BY ELECTRON-CAPTURE NEGATIVE-ION CHEMICAL IONIZATION MASS-SPECTROMETRY SO ANALYTICAL CHEMISTRY LA English DT Article ID POLYCHLORINATED-BIPHENYLS; PCBS AB Environmental samples suspected of containing polychlorinated biphenyls (PCBs) and analyzed by Environmental Protection Agency (EPA) methods frequently contain non-PCB components, such as phthalates, polyaromatic hydrocarbons, or organochlorine pesticides. The presence of these interferences can often obscure the gas chromatographic (GC) patterns and cause problems in differentiating the Aroclor types by visual inspection. Because EPA methods require the identification of Aroclor types in order to determine which Aroclor standard should be used for the quantitation calibration, and possibly, to trace the source of PCB occurrences, electron capture negative ion chemical ionization (ECNICI) mass spectrometry was used to provide additional parameters for discriminating PCB congeners from the interferences. In this study, eight Aroclors (i.e., 1016, 1232, 1242, 1248, 1254, 1260, 1262, and 1268) were analyzed by ECNICI for a range of concentration levels. Using selective ion display, the ion abundances of the prominent peaks in the isotopic clusters of molecular ions were measured for sight PCB homologs (Cl2-Cl9) within their GC retention time windows for each sample. Corresponding relative ion abundances from eight Aroclor standards were used as classification training sets. These training sets were used to develop a classification algorithm using standard linear discriminant analysis to classify the PCBs present in an unknown sample(s) as a specific Aroclor. This technique employed a sequential application of two sets of linear discriminant functions to successfully identity known EPA quality control and environmental samples. However, classifications of Aroclor mixtures were less successful. C1 OAK RIDGE NATL LAB,DIV COMP APPLICAT,OAK RIDGE,TN 37831. RP MA, CY (reprint author), OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37831, USA. NR 26 TC 19 Z9 21 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 15 PY 1993 VL 65 IS 6 BP 772 EP 777 DI 10.1021/ac00054a021 PG 6 WC Chemistry, Analytical SC Chemistry GA KR445 UT WOS:A1993KR44500022 ER PT J AU CHAMBERS, DM MCLUCKEY, SA GLISH, GL AF CHAMBERS, DM MCLUCKEY, SA GLISH, GL TI ROLE OF GAS-DYNAMICS IN NEGATIVE-ION FORMATION IN AN ATMOSPHERIC SAMPLING GLOW-DISCHARGE IONIZATION SOURCE SO ANALYTICAL CHEMISTRY LA English DT Article ID ELECTRON-CAPTURE DETECTOR; PRESSURE IONIZATION; MASS-SPECTROMETRY; SYSTEM; AIR AB A version of the atmospheric sampling glow discharge ionization (ASGDI) source was developed to study the role of gas dynamics on anion formation. This source, which is used in conjunction with mass spectrometry for direct air monitoring, was designed so several key instrumental dimensions as well as operating parameters could be readily changed. Such flexibility permitted the study of ionization processes in ASGDI and the parameters that can be controlled to favor a particular ion product. One aspect of ASGDI that was found to influence ionization yield was the hydrodynamic properties of the sample inlet free-jet expansion. From these investigations, it was found that mean molecular flow of species expanding toward the skimmer could be manipulated to favor kinetically fast reactions over more thermodynamically preferred reactions. In the case of 2,4-dinitrotoluene, observation of the M- ion could be enhanced relative to anions derived from the air-matrix background. The primary ionization mechanism for this compound is believed to be associative electron capture. C1 OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37831. RI McLuckey, Scott/B-2203-2009 OI McLuckey, Scott/0000-0002-1648-5570 NR 26 TC 16 Z9 16 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 15 PY 1993 VL 65 IS 6 BP 778 EP 783 DI 10.1021/ac00054a022 PG 6 WC Chemistry, Analytical SC Chemistry GA KR445 UT WOS:A1993KR44500023 ER PT J AU CHALMERS, SA KILLEEN, KP AF CHALMERS, SA KILLEEN, KP TI METHOD FOR ACCURATE GROWTH OF VERTICAL-CAVITY SURFACE-EMITTING LASERS SO APPLIED PHYSICS LETTERS LA English DT Article AB We report a method for accurate growth of vertical-cavity surface-emitting lasers (VCSELs). The method uses a single reflectivity spectrum measurement to determine the structure of the partially completed VCSEL at a critical point of growth. This information, along with the extracted growth rates, allows imprecisions in growth parameters to be compensated for during growth of the remaining structure, which can then be completed with very accurate critical dimensions. Using this method, we can now routinely grow lasing VCSELs with Fabry-Perot cavity resonance wavelengths controlled to within 0.5%. RP CHALMERS, SA (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 5 TC 16 Z9 16 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 MAR 15 PY 1993 VL 62 IS 11 BP 1182 EP 1184 DI 10.1063/1.108727 PG 3 WC Physics, Applied SC Physics GA KR574 UT WOS:A1993KR57400004 ER PT J AU HOHIMER, JP VAWTER, GA CRAFT, DC AF HOHIMER, JP VAWTER, GA CRAFT, DC TI UNIDIRECTIONAL OPERATION IN A SEMICONDUCTOR RING DIODE-LASER SO APPLIED PHYSICS LETTERS LA English DT Article AB We report the first demonstration of a unidirectional ring diode laser based on the use of an active crossover waveguide. The crossover waveguide introduces both a nonreciprocal loss and gain into the ring cavity to promote unidirectional lasing in the clockwise ring direction. Up to 95% of the continuous-wave lasing output of 3.5 mW (at 150 mA ring current) is emitted from this preferred lasing direction. Unidirectional operation of the ring diode laser is also shown to increase the linearity of the light-vs-current curves, eliminating kinks otherwise occurring from gain competition in the ring cavity. RP HOHIMER, JP (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 6 TC 54 Z9 54 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 MAR 15 PY 1993 VL 62 IS 11 BP 1185 EP 1187 DI 10.1063/1.108728 PG 3 WC Physics, Applied SC Physics GA KR574 UT WOS:A1993KR57400005 ER PT J AU SATYALAKSHMI, KM MALLYA, RM RAMANATHAN, KV WU, XD BRAINARD, B GAUTIER, DC VASANTHACHARYA, NY HEGDE, MS AF SATYALAKSHMI, KM MALLYA, RM RAMANATHAN, KV WU, XD BRAINARD, B GAUTIER, DC VASANTHACHARYA, NY HEGDE, MS TI EPITAXIAL METALLIC LANIO3 THIN-FILMS GROWN BY PULSED LASER DEPOSITION SO APPLIED PHYSICS LETTERS LA English DT Article ID PEROVSKITE AB Epitaxial LaNiO3(LNO) thin films on LaAlO3(LAO), SrTiO3(STO), and YSZ are grown by pulsed laser deposition method at 350 mTorr oxygen partial pressure and 700-degrees-C substrate temperature. As-deposited LNO films are metallic down to 10 K. c-axis oriented YBa2Cu3O7 (YBCO) films were grown on LNO/LAO as well as LNO/STO surfaces without affecting superconducting transition temperature of YBCO. Textured LNO thin films were grown on c-axis oriented YBCO/STO and YBCO/YSZ. Transport measurements of these bilayer films showed that LNO is a good metallic contact material for YBCO. C1 INDIAN INST SCI,SOLID STATE & STRUCT CHEM UNIT,BANGALORE 560012,KARNATAKA,INDIA. INDIAN INST SCI,DEPT MET,BANGALORE 560012,KARNATAKA,INDIA. INDIAN INST SCI,MAT RES CTR,BANGALORE 560012,KARNATAKA,INDIA. LOS ALAMOS NATL LAB,CTR SUPERCOND TECHNOL,LOS ALAMOS,NM 87545. NR 8 TC 124 Z9 127 U1 2 U2 37 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 MAR 15 PY 1993 VL 62 IS 11 BP 1233 EP 1235 DI 10.1063/1.109612 PG 3 WC Physics, Applied SC Physics GA KR574 UT WOS:A1993KR57400021 ER PT J AU NEWMAN, N ROSS, J RUBIN, M AF NEWMAN, N ROSS, J RUBIN, M TI THERMODYNAMIC AND KINETIC PROCESSES INVOLVED IN THE GROWTH OF EPITAXIAL GAN THIN-FILMS SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; ELECTRICAL-PROPERTIES; EQUILIBRIUM PRESSURE; GALLIUM NITRIDE AB Our experimental results using reactive magnetron sputtering, combined with earlier literature, are used to understand the thermodynamic and kinetic processes involved in GaN film growth and the limiting factors involved in the incorporation of nitrogen during the growth process. We show that GaN films fabricated with low pressure growth techniques (< 0.1 Torr) such as sputtering and molecular beam epitaxy are formed under metastable conditions with a nonequilibrium kinetically limited reaction. For these methods, the growth process is controlled by a competition between the forward reaction, which depends on the arrival of activated nitrogen species at the growing surface, and the reverse reaction whose rate is limited by the unusually large kinetic barrier of decomposition of GaN. In practice, the thermally activated rate of decomposition sets an upper bound to the growth temperature. RP NEWMAN, N (reprint author), LAWRENCE BERKELEY LAB,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. RI Newman, Nathan/E-1466-2011 OI Newman, Nathan/0000-0003-2819-9616 NR 30 TC 70 Z9 70 U1 0 U2 12 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 MAR 15 PY 1993 VL 62 IS 11 BP 1242 EP 1244 DI 10.1063/1.108746 PG 3 WC Physics, Applied SC Physics GA KR574 UT WOS:A1993KR57400024 ER PT J AU CLAVERIE, A NAMAVAR, F LILIENTALWEBER, Z AF CLAVERIE, A NAMAVAR, F LILIENTALWEBER, Z TI FORMATION OF AS PRECIPITATES IN GAAS BY ION-IMPLANTATION AND THERMAL ANNEALING SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; TEMPERATURE; LAYERS; MBE AB We show that it is possible to regrow an amorphous GaAs layer created by high dose As implantation at room temperature. If implantation parameters are carefully selected, As precipitates may be formed in the regrown layer with structural characteristics the same as those observed in semi-insulating GaAs grown by molecular beam epitaxy at low temperature. Transmission electron microscopy has been used to study the structure of these precipitates in connection with the structural defects which are seen in the layer. This process appears promising for the formation of low cost semi-insulating GaAs layers. C1 SPIRE CORP,BEDFORD,MA 01730. LAWRENCE BERKELEY LAB,MSD,BERKELEY,CA 94720. RP CLAVERIE, A (reprint author), CEMES,CNRS,BP 4347,F-31055 TOULOUSE,FRANCE. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 18 TC 73 Z9 73 U1 1 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 MAR 15 PY 1993 VL 62 IS 11 BP 1271 EP 1273 DI 10.1063/1.108704 PG 3 WC Physics, Applied SC Physics GA KR574 UT WOS:A1993KR57400034 ER PT J AU SIMKOWITZ, P BARTLETT, EJ BRODIE, JD CONVIT, A WOLKIN, A FRIEDHOFF, AJ DEWEY, SL WOLF, AP AF SIMKOWITZ, P BARTLETT, EJ BRODIE, JD CONVIT, A WOLKIN, A FRIEDHOFF, AJ DEWEY, SL WOLF, AP TI ACUTE CEREBRAL METABOLIC RESPONSE TO HALOPERIDOL - BIOCHEMICAL AND BEHAVIORAL CORRELATIONS SO BIOLOGICAL PSYCHIATRY LA English DT Meeting Abstract C1 NYU MED CTR,NEW YORK,NY 10016. BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0006-3223 J9 BIOL PSYCHIAT JI Biol. Psychiatry PD MAR 15 PY 1993 VL 33 IS 6A SU S BP A68 EP A68 PG 1 WC Neurosciences; Psychiatry SC Neurosciences & Neurology; Psychiatry GA LA417 UT WOS:A1993LA41700114 ER PT J AU CASEY, WH BANFIELD, JF WESTRICH, HR MCLAUGHLIN, L AF CASEY, WH BANFIELD, JF WESTRICH, HR MCLAUGHLIN, L TI WHAT DO DISSOLUTION EXPERIMENTS TELL US ABOUT NATURAL WEATHERING SO CHEMICAL GEOLOGY LA English DT Article; Proceedings Paper CT SESSION GEOCHEMICAL KINETICS : FIELD VS LABORATORY RATES, AT THE 1991 ANNUAL MEETING OF THE GEOLOGICAL SOC OF AMERICA CY OCT 21-24, 1991 CL SAN DIEGO, CA SP GEOL SOC AMER, GEOCHEM SOC ID COORDINATION CHEMISTRY; SURFACE-STRUCTURE; ABERT LAKE; METAL-IONS; AEM-TEM; X-RAY; KINETICS; RATES; OLIVINE; OXIDES AB Much information about the earliest stages of weathering comes from laboratory experiments where the mineral surface chemistry is rigorously controlled and the solution composition is maintained far from equilibrium with the solid. The experiments show that the pathways for dissolution are similar to those for ligand exchange around dissolved metal complexes. One difference is that the rates of mineral dissolution are controlled by the concentrations of surface species while rates of ligand exchange are proportional to bulk concentration. Nevertheless, the correlation is so strong that rates of olivine dissolution are predictable from the rates of solvent exchange around the corresponding divalent metal in solution. However, this level of resolution is achieved by maintaining unnaturally high fluid/mineral ratios and by taking great care to avoid precipitation of secondary minerals. Natural olivine weathers in intimate contact with secondary minerals. Reactions commonly proceed in clay-filled channels only a few tens of Angstroms in diameter and secondary minerals are topotactic with olivine. Primary and secondary minerals are so intimately intergrown in these channels that the olivine surface chemistry is undoubtably influenced by overlapping electrostatic double layers. Smectite growth may have proceeded at near-saturation with the fluid, but the solution is in gross disequilibrium with the olivine. There nevertheless remains some qualitative consistency between weathering in the laboratory and in the field. The ligand-exchange model for bond cleavage, for example, predicts that the presence of ferric iron at the mineral surface will retard weathering rates. Correspondingly, defect planes of oxidized olivine (to produce Fe3+ and a vacancy) weather at a much slower rate than unoxidized material. Thus, the appropriate level of comparison of field and laboratory weathering is at the scale of reactivity trends; it is unreasonable to expect quantitative similarity in reaction rates. C1 UNIV WISCONSIN,DEPT GEOL,MADISON,WI 53706. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP CASEY, WH (reprint author), UNIV CALIF DAVIS,DAVIS,CA 95616, USA. NR 42 TC 95 Z9 96 U1 4 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD MAR 15 PY 1993 VL 105 IS 1-3 BP 1 EP 15 DI 10.1016/0009-2541(93)90115-Y PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KW041 UT WOS:A1993KW04100002 ER PT J AU LOPEZHERNANDEZ, D NINO, M AF LOPEZHERNANDEZ, D NINO, M TI PHOSPHORUS MINERALIZATION DURING LABORATORY INCUBATION IN SOILS DERIVED FROM DIFFERENT TEXTURED PARENT MATERIALS SO GEODERMA LA English DT Article; Proceedings Paper CT INTERNATIONAL WORKSHOP ON METHODS OF RESEARCH ON SOIL STRUCTURE / SOIL BIOTA INTERRELATIONSHIPS CY NOV 24-28, 1991 CL INT AGR CTR, WAGENINGEN, NETHERLANDS SP WAGENINGEN AGR UNIV, ORG ECON COOPERAT & DEV COOPERAT RES, PROJECT BIO RESOURCE MANAGEMENT, NETHERLANDS INTEGRATED SOIL RES PROGRAMME, ROYAL NETHERLANDS ACAD SCI, NETHERLANDS MINIST AGR, NAT MANAGEMENT & FISHERIES, NETHERLANDS COUNCIL AGR RES, FDN BIOL RES, NETHERLANDS SOIL SCI SOC, INT AGR CTR HO INT AGR CTR ID LABILE ORGANIC PHOSPHORUS; TRANSFORMATIONS; MANAGEMENT; PHOSPHATE AB The dynamics of phosphorus in soils derived from different textured parent materials were studied. Soils weathered from the three parent materials were Haploborolls but different in texture and solum depth. Microbial phosphorus by hexanol fumigation, and mineralization rates of organic P (P(o)) were assessed with a P-32 dilution technique and P was fractionated using a modification of the method of Hedley et al. Microbial P and P(o) mineralization rates were significantly affected by parent materials. The high rates of mineralization for the fine-textured soils correspond well with their higher content in substrates able to mineralize e.g. total carbon, P(o) and microbial P(i). The residual P (e,g. more stable P(i) and P(o) forms) is the principal P fraction in the analyzed Mollisols. C1 NREL,FT COLLINS,CO. RP LOPEZHERNANDEZ, D (reprint author), UCV,FAC CIENCIAS,IZT,ESTUDIOS AMBIENTALES LAB,APDO 47058,CARACAS 1041A,VENEZUELA. NR 39 TC 18 Z9 19 U1 3 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0016-7061 J9 GEODERMA JI Geoderma PD MAR 15 PY 1993 VL 56 IS 1-4 BP 527 EP 537 DI 10.1016/0016-7061(93)90132-5 PG 11 WC Soil Science SC Agriculture GA KW482 UT WOS:A1993KW48200039 ER PT J AU MACKINNON, RJ CAREY, GF AF MACKINNON, RJ CAREY, GF TI MOVING-GRID FINITE-ELEMENT MODELING OF THERMAL ABLATION AND CONSOLIDATION IN POROUS-MEDIA SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article ID DISCONTINUITIES AB A moving-grid finite element model for the analysis of thermal ablation, fluid flow and deformation in elastic porous media is presented. The model is formulated in terms of temperatures, fluid pressures and solid displacements, and takes into account a moving phase boundary. Supporting algorithms for treating the moving phase boundary and solving the coupled equations are described. The model has application to several important moving-boundary geotechnical problems. Numerical test cases are provided for model verification and example applications corresponding to thermal ablation, consolidation and underground coal gasification are given. C1 UNIV TEXAS,COLL ENGN,AUSTIN,TX 78712. RP MACKINNON, RJ (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83416, USA. NR 34 TC 4 Z9 4 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD MAR 15 PY 1993 VL 36 IS 5 BP 717 EP 744 DI 10.1002/nme.1620360502 PG 28 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA KR125 UT WOS:A1993KR12500001 ER PT J AU MCCABE, DE HAO, S CORNEC, A SCHWALBE, KH AF MCCABE, DE HAO, S CORNEC, A SCHWALBE, KH TI A METHOD TO ESTIMATE ETA-FACTOR FOR J-MEASUREMENT SO INTERNATIONAL JOURNAL OF FRACTURE LA English DT Article C1 GKSS FORSCHUNGSZENTRUM GEESTHACHT GMBH,INST MAT RES,W-2054 GEESTHACHT,GERMANY. RP MCCABE, DE (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0376-9429 J9 INT J FRACTURE JI Int. J. Fract. PD MAR 15 PY 1993 VL 60 IS 2 BP R21 EP R26 DI 10.1007/BF00012447 PG 6 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA LF649 UT WOS:A1993LF64900009 ER PT J AU OSBOURN, GC AF OSBOURN, GC TI PREDICTION OF CONTRAST SENSITIVITY AND SPATIAL PROPERTIES OF ILLUSORY MACH BANDS FROM A PROPOSED PERCEPTUAL MECHANISM FOR DISTINGUISHING SHADOW BRIGHTNESS FROM OBJECT LIGHTNESS SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 1993 VL 34 IS 4 BP 818 EP 818 PG 1 WC Ophthalmology SC Ophthalmology GA KT893 UT WOS:A1993KT89300576 ER PT J AU GRITZ, DC BIGIO, IJ LOREE, TR SHIMADA, T GLICKMAN, RD STORYHELD, K AF GRITZ, DC BIGIO, IJ LOREE, TR SHIMADA, T GLICKMAN, RD STORYHELD, K TI THE OPTICAL BIOPSY SYSTEM - A SPECTRAL-ANALYSIS OF THE OCULAR SURFACE INVIVO SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 UNIV TEXAS,HLTH SCI CTR,SAN ANTONIO,TX 78284. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. NR 0 TC 0 Z9 0 U1 0 U2 2 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 1993 VL 34 IS 4 BP 942 EP 942 PG 1 WC Ophthalmology SC Ophthalmology GA KT893 UT WOS:A1993KT89301190 ER PT J AU SIDJANIN, D PEAK, MJ AF SIDJANIN, D PEAK, MJ TI EFFECTS OF 365-NM UV ON RABBIT LENS EPITHELIAL-CELLS AND HUMAN EPITHELIOID CELLS - COMPARISON OF CELL-SURVIVAL, INDUCTION AND REPAIR OF DNA SINGLE-STRAND BREAKS SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 ARGONNE NATL LAB,ARGONNE,IL 60439. NO ILLINOIS UNIV,DE KALB,IL 60439. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 1993 VL 34 IS 4 BP 1298 EP 1298 PG 1 WC Ophthalmology SC Ophthalmology GA KT893 UT WOS:A1993KT89302929 ER PT J AU GSCHNEIDNER, KA AF GSCHNEIDNER, KA TI METALS, ALLOYS AND COMPOUNDS - HIGH PURITIES DO MAKE A DIFFERENCE SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF : RARE EARTHS 92 CY JUN 01-05, 1992 CL KYOTO, JAPAN SP CHEM SOC JAPAN, JAPAN INST MET, JAPAN SOC ANAL CHEM, ELECTROCHEM SOC JAPAN, CERAM SOC JAPAN, SOC SYNTHET ORGANIC CHEM JAPAN, JAPAN SOC NEWER MET, PHYS SOC JAPAN, JAPAN SOC APPL PHYS, KINKI CHEM SOC ID HEAT-CAPACITY; GADOLINIUM; ELECTROTRANSPORT AB The influence of impurity atoms, especially the interstitial elements, on some of the properties of the pure rare earth metals and the stabilization of non-equilibrium structures of the metals (i.e. non-existent polymorphs) is discussed. The effect of impurities on rare earth intermetallic and non-metallic compounds is examined: this includes the composition and structure of line compounds; the nominal vs. true composition of solid solution intermediate phases; and the stabilization of non-existent binary phases (i.e. ternary compounds). C1 IOWA STATE UNIV SCI & TECHNOL,DEPT MAT SCI & ENGN,AMES,IA 50011. RP GSCHNEIDNER, KA (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 33 TC 59 Z9 60 U1 1 U2 12 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 15 PY 1993 VL 193 IS 1-2 BP 1 EP 6 DI 10.1016/0925-8388(93)90293-V PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA KV965 UT WOS:A1993KV96500001 ER PT J AU EDELSTEIN, NM KOT, WK AF EDELSTEIN, NM KOT, WK TI SPECTROSCOPIC AND MAGNETIC STUDIES OF TETRAVALENT PA AND TRIVALENT TH COMPOUNDS SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF : RARE EARTHS 92 CY JUN 01-05, 1992 CL KYOTO, JAPAN SP CHEM SOC JAPAN, JAPAN INST MET, JAPAN SOC ANAL CHEM, ELECTROCHEM SOC JAPAN, CERAM SOC JAPAN, SOC SYNTHET ORGANIC CHEM JAPAN, JAPAN SOC NEWER MET, PHYS SOC JAPAN, JAPAN SOC APPL PHYS, KINKI CHEM SOC ID ELECTRONIC-STRUCTURE; SPECTRA; CRYSTAL; CONFIGURATIONS; LANTHANIDE; THORIUM; PACL62 AB At the beginning of the actinide series, the 5f and 6d configurations are very close in energy. Consequently, both the 5f and 6d energy level splittings may be observed experimentally in Pa-4+ and Th3+ compounds. The available magnetic and optical data on these systems are reviewed. RP EDELSTEIN, NM (reprint author), LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720, USA. NR 35 TC 2 Z9 2 U1 1 U2 10 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 15 PY 1993 VL 193 IS 1-2 BP 82 EP 87 DI 10.1016/0925-8388(93)90317-G PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA KV965 UT WOS:A1993KV96500025 ER PT J AU CLARK, DL HOBART, DE PALMER, PD SULLIVAN, JC STOUT, BE AF CLARK, DL HOBART, DE PALMER, PD SULLIVAN, JC STOUT, BE TI C-13 NMR CHARACTERIZATION OF ACTINYL(VI) CARBONATE COMPLEXES IN AQUEOUS-SOLUTION SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article ID EQUILIBRIA; EXCHANGE; ION; SPECTROSCOPY; 25-DEGREES-C; SYSTEM AB The ligand exchange reaction between free and coordinated carbonate on (PuVIO2(CO3)34-)-Pu-242-C-13 and (AmVIO2(CO3)34-)-Am-243-C-13 Systems was examined by variable temperature C-13 pulsed nuclear magnetic resonance (NMR) techniques. A modified Carr-Purcell-Meiboom-Gill NMR pulse sequence was used for the experimental de-termination of ligand exchange parameters for paramagnetic actinide complexes. Eyring analysis provided activation parameters of DELTAG295double-dagger = 53 kJ M-1, DELTAH(double-dagger) = 35 kJ M-1 and DELTAS295double-dagger = -61 J M-1 K-1 for the plutonyl triscarbonate system, suggesting an associative transition state for the plutonyl(VI) carbonate self-exchange reaction. C1 ARGONNE NATL LAB, DIV CHEM, ARGONNE, IL 60439 USA. UNIV CINCINNATI, DEPT CHEM, CINCINNATI, OH 45221 USA. RP LOS ALAMOS NATL LAB, DIV ISOTOPE & NUCL CHEM, LOS ALAMOS, NM 87545 USA. RI Clark, David/A-9729-2011 NR 24 TC 12 Z9 12 U1 0 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 EI 1873-4669 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 15 PY 1993 VL 193 IS 1-2 BP 94 EP 97 DI 10.1016/0925-8388(93)90319-I PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA KV965 UT WOS:A1993KV96500027 ER PT J AU SODERHOLM, L LOONG, CK AF SODERHOLM, L LOONG, CK TI PR AND CM IN SUPERCONDUCTOR-RELATED OXIDES SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF : RARE EARTHS 92 CY JUN 01-05, 1992 CL KYOTO, JAPAN SP CHEM SOC JAPAN, JAPAN INST MET, JAPAN SOC ANAL CHEM, ELECTROCHEM SOC JAPAN, CERAM SOC JAPAN, SOC SYNTHET ORGANIC CHEM JAPAN, JAPAN SOC NEWER MET, PHYS SOC JAPAN, JAPAN SOC APPL PHYS, KINKI CHEM SOC ID PRBA2CU3O7; STATE AB The electronic structures and magnetic properties of the f-element in PrBa2Cu3O7, CmBa2Cu3O7, and Cm1.83Th.17CuO4 are discussed in terms of their abilities to inhibit superconductivity in these materials. Inelastic neutron data on a variety of Pr-compounds, together with susceptibility data and magnetic ordering temperatures are used to argue for a suppression mechanism that involves shortening the lifetimes of the conduction-electron spin states. RP SODERHOLM, L (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 22 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 15 PY 1993 VL 193 IS 1-2 BP 125 EP 128 DI 10.1016/0925-8388(93)90329-L PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA KV965 UT WOS:A1993KV96500037 ER PT J AU LOONG, CK SODERHOLM, L AF LOONG, CK SODERHOLM, L TI SUPERCONDUCTIVITY AND RARE-EARTH PARAMAGNETISM IN PR1.85CE0.15CUO4 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF : RARE EARTHS 92 CY JUN 01-05, 1992 CL KYOTO, JAPAN SP CHEM SOC JAPAN, JAPAN INST MET, JAPAN SOC ANAL CHEM, ELECTROCHEM SOC JAPAN, CERAM SOC JAPAN, SOC SYNTHET ORGANIC CHEM JAPAN, JAPAN SOC NEWER MET, PHYS SOC JAPAN, JAPAN SOC APPL PHYS, KINKI CHEM SOC ID MAGNETIC-PROPERTIES; CRYSTAL-FIELD; PR; PRBA2CU3O7 AB The magnetic excitation spectra, determined by inelastic neutron scattering, of the electron superconductor Pr1.85Ce0.15CuO4 are compared with those of the parent insulating compound Pr2CuO4. The observed crystal-field transitions in the superconducting material shift to slightly lower energies and are broadened significantly relative to those from the parent compound. The results are consistent with the crystal-field model calculation for the splitting of the Pr3+:H-3(4) ground multiplet under the scheme of intermediate coupling. High-resolution neutron spectroscopy reveals that the Ce ions in Pr1.85Ce0.15CuO4 are nonmagnetic and the Ce 4f-electrons are likely to be delocalized into the conduction band. RP LOONG, CK (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 16 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 15 PY 1993 VL 193 IS 1-2 BP 142 EP 144 DI 10.1016/0925-8388(93)90334-J PG 3 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA KV965 UT WOS:A1993KV96500042 ER PT J AU PETERSON, JR AF PETERSON, JR TI SOME EXPERIENCE WITH ABSORPTION, PHONON RAMAN, AND LUMINESCENCE SPECTROSCOPIC PROBES OF CRYSTAL-STRUCTURE OF F-ELEMENT COMPOUNDS SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF : RARE EARTHS 92 CY JUN 01-05, 1992 CL KYOTO, JAPAN SP CHEM SOC JAPAN, JAPAN INST MET, JAPAN SOC ANAL CHEM, ELECTROCHEM SOC JAPAN, CERAM SOC JAPAN, SOC SYNTHET ORGANIC CHEM JAPAN, JAPAN SOC NEWER MET, PHYS SOC JAPAN, JAPAN SOC APPL PHYS, KINKI CHEM SOC ID ANTI-STOKES LUMINESCENCE; X-RAY-DIFFRACTION; SOLID-STATE; TRANS-URANIUM; SPECTRA; PRESSURE; LANTHANIDE; HALIDES; PRCL3; PRBR3 AB Spectroscopic probes can be very useful and rapid for identifying the solid state crystal structure exhibited by an f-element compound. In some cases spectroscopic means of identifying crystal structure might bc the only way to carry out conveniently experimental investigations while varying the sample temperature and/or pressure. Some successes and limitations of our absorption, phonon Raman, and luminescence spectroscopic methods for identifying crystal structures of f-element compounds are discussed and summarized. C1 OAK RIDGE NATL LAB,DIV CHEM,TRANSURANIUM RES LAB,OAK RIDGE,TN 37831. RP PETERSON, JR (reprint author), UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996, USA. NR 40 TC 3 Z9 3 U1 1 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 15 PY 1993 VL 193 IS 1-2 BP 165 EP 169 DI 10.1016/0925-8388(93)90339-O PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA KV965 UT WOS:A1993KV96500047 ER PT J AU DELCUL, GD NAVE, SE PETERSON, JR AF DELCUL, GD NAVE, SE PETERSON, JR TI POLARIZED RAMAN-SPECTRA OF SINGLE-CRYSTAL LANTHANIDE OXYCHLORIDES SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF : RARE EARTHS 92 CY JUN 01-05, 1992 CL KYOTO, JAPAN SP CHEM SOC JAPAN, JAPAN INST MET, JAPAN SOC ANAL CHEM, ELECTROCHEM SOC JAPAN, CERAM SOC JAPAN, SOC SYNTHET ORGANIC CHEM JAPAN, JAPAN SOC NEWER MET, PHYS SOC JAPAN, JAPAN SOC APPL PHYS, KINKI CHEM SOC ID GROWTH AB The analyses of reported Raman spectra from tetragonal lanthanide oxychlorides are inconsistent. Nuclear site symmetry analysis predicts six Raman-active bands. Five peaks are consistently observed, whereas the sixth remains controversial. Also, two different sets of irreducible representations are reported: 2A1g + 3E(g) + B2g(or B1g) + 3A2u + 3E(u). To resolve discrepancies in the reported symmetry assignments, a polarized Raman spectral analysis of single-crystal PrOCl was undertaken. The correct irreducible representation contains the B2g element. C1 SAVANNAH RIVER ECOL LAB,ANALYT DEV SECT,AIKEN,SC 29802. UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV CHEM,TRANSURANIUM RES LAB,OAK RIDGE,TN 37831. RP DELCUL, GD (reprint author), DEPT CHEM,DIV TECH,OAK RIDGE K-25 SITE,POB 2003,OAK RIDGE,TN 37831, USA. NR 10 TC 2 Z9 2 U1 1 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 15 PY 1993 VL 193 IS 1-2 BP 194 EP 196 DI 10.1016/0925-8388(93)90347-P PG 3 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA KV965 UT WOS:A1993KV96500055 ER PT J AU PETERSON, JR HEATHMAN, S BENEDICT, U AF PETERSON, JR HEATHMAN, S BENEDICT, U TI ENERGY DISPERSIVE-X-RAY DIFFRACTION ANALYSIS OF NDBR3 AT PRESSURES UP TO 52 GPA SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF : RARE EARTHS 92 CY JUN 01-05, 1992 CL KYOTO, JAPAN SP CHEM SOC JAPAN, JAPAN INST MET, JAPAN SOC ANAL CHEM, ELECTROCHEM SOC JAPAN, CERAM SOC JAPAN, SOC SYNTHET ORGANIC CHEM JAPAN, JAPAN SOC NEWER MET, PHYS SOC JAPAN, JAPAN SOC APPL PHYS, KINKI CHEM SOC AB Energy dispersive X-ray diffraction experiments on NdBr3 have shown PuBr3-type orthorhombic structure at high pressure but not the formation of a ''new'' crystal structure, as had been suggested from earlier work based on analysis of absorption and phonon Raman spectra. The bulk modulus B0 and its pressure derivative B0' were calculated from the compression curve to 20 GPa to be about 17 +/- 1 GPa and 8.7 +/- 2 respectively. C1 OAK RIDGE NATL LAB,DIV CHEM,TRANSURANIUM RES LAB,OAK RIDGE,TN 37831. COMMISS EUROPEAN COMMUNITIES,JOINT RES CTR,INST TRANSURANIUM ELEMENTS,W-7500 KARLSRUHE 1,GERMANY. RP PETERSON, JR (reprint author), UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996, USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 15 PY 1993 VL 193 IS 1-2 BP 306 EP 308 DI 10.1016/0925-8388(93)90380-6 PG 3 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA KV965 UT WOS:A1993KV96500088 ER PT J AU MILLER, SL MILLER, WM MCWHORTER, PJ AF MILLER, SL MILLER, WM MCWHORTER, PJ TI EXTREMAL DYNAMICS - A UNIFYING PHYSICAL EXPLANATION OF FRACTALS, 1/F NOISE, AND ACTIVATED PROCESSES SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SELF-ORGANIZED CRITICALITY; NONVOLATILE MEMORY TRANSISTORS; 1-F NOISE; MODEL; EARTHQUAKES; RETENTION; MUSIC AB The properties of physical systems whose observable properties depend upon random exceedances of critical parameters are quantitatively examined. Using extreme value theory, the dynamical behavior of this broad class of systems is derived. This class of systems can exhibit two characteristic signatures: generalized activation when far from equilibrium and noise with a characteristic power spectrum (including 1/f) when in quasiequilibrium. Fractal structures can also arise from these systems. It is thus demonstrated that generalized activation, noise, and fractals, in some cases, are simply different manifestations of a single common dynamical principle, which is termed ''extremal dynamics.'' Examples of physical processes governed by extremal dynamics are discussed, including data loss of nonvolatile memories and dielectric breakdown. RP MILLER, SL (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 45 TC 31 Z9 32 U1 0 U2 6 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 MAR 15 PY 1993 VL 73 IS 6 BP 2617 EP 2628 DI 10.1063/1.353079 PG 12 WC Physics, Applied SC Physics GA KT869 UT WOS:A1993KT86900002 ER PT J AU SHON, JW KUSHNER, MJ HEBNER, GA HAYS, GN AF SHON, JW KUSHNER, MJ HEBNER, GA HAYS, GN TI PREDICTIONS FOR GAIN IN THE FISSION-FRAGMENT-EXCITED ATOMIC XENON LASER SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ELECTRON-BEAM; SUSTAINED DISCHARGE; XE(6P) STATES; MIXTURES; AR; DEACTIVATION; TRANSITION; EXCITATION; GASES AB The infrared atomic xenon laser (5d-->6p) is an attractive candidate for fission fragment excitation, which provides low-power deposition (1-100 W cm-3), long pulse lengths (1-10 ms), and high-energy deposition (100s J l-1). Optical gain at 1.73 and 2.03 mum has recently been measured in a reactor-excited xenon laser yielding values exceeding 0.03-0.05 cm-1 at power depositions of less than 10s W cm-3. Gain was also found to rapidly terminate before the peak of the pump pulse for some experimental conditions. A computer model has been developed to predict gain in fission-fragment-excited xenon lasers and these experiments have been analyzed. It is found that the termination of gain is most likely attributable to gas heating which increases the electron density, leading to electron collision quenching. The specific dependence of gain on pump rate suggests that a reduced rate of recombination of molecular ions with increasing gas temperature is partly responsible for this behavior. C1 UNIV ILLINOIS,DEPT ELECT & COMP ENGN,1406 W GREEN ST,URBANA,IL 61801. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RI Kushner, Mark/A-7362-2008; Kushner, Mark/D-4547-2015 NR 31 TC 18 Z9 18 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 MAR 15 PY 1993 VL 73 IS 6 BP 2686 EP 2694 DI 10.1063/1.353039 PG 9 WC Physics, Applied SC Physics GA KT869 UT WOS:A1993KT86900010 ER PT J AU STEIN, HJ MYERS, SM FOLLSTAEDT, DM AF STEIN, HJ MYERS, SM FOLLSTAEDT, DM TI INFRARED-SPECTROSCOPY OF CHEMICALLY BONDED HYDROGEN AT VOIDS AND DEFECTS IN SILICON SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SURFACE; PASSIVATION; TERMINATION; SI AB Chemical bonding of H to displacement defects and internal surfaces in Si has been investigated by infrared-absorption and nuclear reaction analysis techniques. A He implantation/anneal sequence was used to produce faceted voids which are retained to at least 800-degrees-C in a buried layer as revealed by transmission electron microscopy. Hydrogen was injected into void layers by three different methods: ion implantation, plasma exposure, and H-2 gas exposure. Infrared absorption by Si-H stretch modes with frequencies characteristic of monohydrides on (100) and (111) surfaces are observed for all methods of H injection, consistent with bonding on faceted void surfaces. Thermal stability of Si-H is higher on void surfaces than on other trapping sites. Displacement defects produced by H-ion implantation trap H but release it upon annealing for retrapping on voids. The Si-H absorption bands with frequencies characteristic of monohydrides on (100) and (111) surfaces anneal in parallel between 600 and 800-degrees-C and in coincidence with the loss of total H measured by nuclear reaction analysis. Moreover, densities comparable to the total H density are estimated for void surface states and for Si-H bonds on void surfaces. It is inferred from these results that bonding of H on the void surfaces is energetically favored over H-2 formation in the voids, and it is concluded that the 2.5+/-0.2 eV determined in a separate study of H release from buried voids is the Si-H bond energy descriptive of both (111) and (100) surfaces. RP STEIN, HJ (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 23 TC 60 Z9 62 U1 1 U2 5 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 MAR 15 PY 1993 VL 73 IS 6 BP 2755 EP 2764 DI 10.1063/1.353050 PG 10 WC Physics, Applied SC Physics GA KT869 UT WOS:A1993KT86900021 ER PT J AU FOSTER, CM CHIARELLO, RP CHANG, HLM YOU, H ZHANG, TJ FRASE, H PARKER, JC LAM, DJ AF FOSTER, CM CHIARELLO, RP CHANG, HLM YOU, H ZHANG, TJ FRASE, H PARKER, JC LAM, DJ TI RAMAN-SCATTERING AND X-RAY-DIFFRACTOMETRY STUDIES OF EPITAXIAL TIO2 AND VO2 THIN-FILMS AND MULTILAYERS ON ALPHA-AL2O3(11(2)OVER-BAR-0) SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Epitaxial thin films of TiO2 and VO2 single layers and TiO2/VO2 multilayers were grown on (1120BAR) sapphire (alpha-Al2O3) substrates using the metalorganic chemical vapor deposition technique and were characterized using Raman scattering and four-circle x-ray diffractometry. X-ray diffraction results indicate that the films are high quality single crystal material with well defined growth plane and small in-plane and out-of-plane mosaic. Single-layer films are shown to obey the Raman selection rules of TiO2 and VO2 single crystals. The close adherence to the Raman selection rules indicates the high degree of orientation of the films, both parallel and perpendicular to the growth plane. Selection rule spectra of two and three layer TiO2/VO2 multilayers are dominated by the VO2 layers with only minimal signature of the TiO2 layers. Due to the low band gap of semiconducting vanadium dioxide, we attribute the strong signature of the VO2 layers to resonant enhancement of the VO2 Raman component accompanied with absorption of the both the incident and scattered laser light from the TiO2 layers. C1 NANOPHASE TECHNOL CORP,DARIEN,IL 60559. RP FOSTER, CM (reprint author), ARGONNE NATL LAB,DIV MAT SCI,9700 S CASS AVE,ARGONNE,IL 60439, USA. RI You, Hoydoo/A-6201-2011 OI You, Hoydoo/0000-0003-2996-9483 NR 30 TC 9 Z9 9 U1 1 U2 16 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 MAR 15 PY 1993 VL 73 IS 6 BP 2841 EP 2847 DI 10.1063/1.353036 PG 7 WC Physics, Applied SC Physics GA KT869 UT WOS:A1993KT86900035 ER PT J AU PAN, LS KANIA, DR PIANETTA, P AGER, JW LANDSTRASS, MI HAN, S AF PAN, LS KANIA, DR PIANETTA, P AGER, JW LANDSTRASS, MI HAN, S TI TEMPERATURE-DEPENDENT MOBILITY IN SINGLE-CRYSTAL AND CHEMICAL VAPOR-DEPOSITED DIAMOND SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID THIN-FILMS AB The combined electron and hole mobility of a single-crystal type IIa natural diamond and a polycrystalline diamond film deposited by chemical vapor deposition (CVD) were measured using transient photoconductivity as a function of excitation density (10(13)-10(17) cm-3) and temperature (120-410 K). In natural diamond the temperature dependence suggests that the mobility is limited by phonon scattering at low free carrier densities, and by electron-hole scattering at high densities. The combined electron and hole phonon-limited mobility at room temperature is 3000 (+/-500) cm2/V s. In the CVD film, the mobility at room temperature was estimated to be 50 cm2/V s at low excitation densities. The temperature dependence of the mobility-lifetime product at low excitation densities is different from that of natural diamond, and suggests that charged center scattering, rather than acoustic phonon scattering, is the dominant effect. High densities of nitrogen and dislocations are known to be present in the natural diamond, and these appear to be the dominant recombination sites which limit the carrier lifetime. In the polycrystalline film a variety of structural defects and impurities are believed to exist, but it is unknown which of these dominates the transport and recombination properties. C1 STANFORD SYNCHROTRON RADIAT LAB,SLAC BIN 99,POB 4349,STANFORD,CA 94309. OI Ager, Joel/0000-0001-9334-9751 NR 25 TC 37 Z9 37 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 MAR 15 PY 1993 VL 73 IS 6 BP 2888 EP 2894 DI 10.1063/1.353018 PG 7 WC Physics, Applied SC Physics GA KT869 UT WOS:A1993KT86900043 ER PT J AU AU, HL ASOKAKUMAR, P NIELSEN, B LYNN, KG AF AU, HL ASOKAKUMAR, P NIELSEN, B LYNN, KG TI POSITRON STUDIES OF METAL-OXIDE-SEMICONDUCTOR STRUCTURES SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INTERFACE; SILICON; BEAMS AB Positron annihilation spectroscopy provides a new probe to study the properties of interface traps in metal-oxide semiconductors (MOS). Using positrons, we have examined the behavior of the interface traps as a function of gate bias. We propose a simple model to explain the positron annihilation spectra from the interface region of a MOS capacitor. C1 UNIV HONG KONG,DEPT PHYS,HONG KONG,HONG KONG. RP AU, HL (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. RI Nielsen, Bent/B-7353-2009 OI Nielsen, Bent/0000-0001-7016-0040 NR 18 TC 22 Z9 23 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 MAR 15 PY 1993 VL 73 IS 6 BP 2972 EP 2976 DI 10.1063/1.353029 PG 5 WC Physics, Applied SC Physics GA KT869 UT WOS:A1993KT86900055 ER PT J AU MATHER, MW SPRINGER, P HENSEL, S BUSE, G FEE, JA AF MATHER, MW SPRINGER, P HENSEL, S BUSE, G FEE, JA TI CYTOCHROME-OXIDASE GENES FROM THERMUS-THERMOPHILUS - NUCLEOTIDE-SEQUENCE OF THE FUSED GENE AND ANALYSIS OF THE DEDUCED PRIMARY STRUCTURES FOR SUBUNIT-I AND SUBUNIT-III OF CYTOCHROME-CAA3 SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID SITE-DIRECTED MUTAGENESIS; AMINO-ACID-SEQUENCES; C-OXIDASE; EXTREME THERMOPHILE; ESCHERICHIA-COLI; MOLECULAR-CLONING; PROTON PUMP; RESPIRATORY PROTEINS; MEMBRANE-PROTEINS; MITOCHONDRIAL-DNA AB Cytochrome caa3, a cytochrome c oxidase from Thermus thermophilus, has been purified and extensively characterized as a two-subunit enzyme containing the metal centers characteristic of cytochrome c oxidases (cytochromes a and a3; copper centers Cu(A) and Cu(B)) and an additional cytochrome c (Fee, J. A., Kuila, D., Mather, M. W., and Yoshida, T. (1986) Biochim. Biophys. Acta 853, 153-185). We have now cloned and sequenced the genes encoding the subunits of this enzyme. The smaller subunit consists of a typical oxidase subunit II sequence fused to a cytochrome c domain (Mather, M. W., Springer, P., and Fee, J. A. (1991) J. Biol. Chem. 266, 5025-5035). The larger subunit, the A-protein, is encoded by a fusion gene lying immediately downstream of the subunit IIc gene. The 5' portion of this gene encodes an oxidase subunit I homolog, whereas the 3' portion is homologous to oxidase subunits III. The A-protein from the purified enzyme appears too small from SDS-polyacrylamide gel electrophoresis and quantitative amino acid analyses to be a complete subunit I/III fusion, but it is currently not known if proteolytic processing occurs. Analyses of the sequences of oxidase subunits are presented which clearly identify T. thermophilus cytochrome caa3 as a bona fide member of the greater family of heme- and copper-requiring oxidases. As one consequence, it is confirmed that the set of invariant histidine residues (potential ligands of the metal centers) in cytochrome c oxidase subunits I and II is reduced to 8. Possible topological and helix packing models are developed based on considerations of homology, hydropathy, and variability. C1 LOS ALAMOS NATL LAB,BIOCHEM SECT,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,STABLE ISOTOPE RESOURCE SPECT & BIOCHEM GRP,LOS ALAMOS,NM 87545. RHEIN WESTFAL TH AACHEN,INST BIOCHEM,W-5100 AACHEN,GERMANY. FU NIGMS NIH HHS [GM35342] NR 88 TC 48 Z9 49 U1 0 U2 3 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD MAR 15 PY 1993 VL 268 IS 8 BP 5395 EP 5408 PG 14 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA KR822 UT WOS:A1993KR82200012 PM 8383670 ER PT J AU NIU, BH SHIRLEY, DA BAI, Y AF NIU, BH SHIRLEY, DA BAI, Y TI HIGH-RESOLUTION PHOTOELECTRON-SPECTROSCOPY AND FEMTOSECOND INTRAMOLECULAR DYNAMICS OF H2CO+ AND D2CO+ SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR ELECTRONIC-SPECTRA; MANY-BODY APPROACH; IONIZATION-POTENTIALS; VIBRATIONAL STRUCTURE; FORMALDEHYDE; PHOTOIONIZATION; APPROXIMATION; NITROGEN; STATES; SET AB High resolution helium Ialpha (584 angstrom) photoelectron spectra of H2CO and D2CO are reported. The present study reveals much new vibrational structure detail in the ionic first excited state of formaldehyde. Weak excitations of the nu3 (in H2CO) and nu1 (in D2CO) modes along with the strong excitations of the nu2 mode in the ionic first excited states are fully resolved for the first time. The weak excitations of the nu4 out-of-plane bending mode in the ionic ground and first excited states of formaldehyde cations indicate that they may have nonplanar equilibrium geometries. Strong isotope effects on vibronic (vibrational) couplings are observed in the cation first and second excited states. Vibrational autocorrelation functions are calculated from the high-resolution photoelectron spectra. The correlation functions calculated for the first electronic excited states show rather slow decay rate on the femtosecond time scale. The ultrafast decay of the formaldehyde cations implied by the correlation functions calculated for the third electronic excited states suggest that dissociation and intramolecular dynamic processes are the main decay pathways. C1 JILIN UNIV TECHNOL,DEPT CHEM,CHANGCHUN,PEOPLES R CHINA. LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720. RP NIU, BH (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 54 TC 31 Z9 32 U1 0 U2 9 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 MAR 15 PY 1993 VL 98 IS 6 BP 4377 EP 4390 DI 10.1063/1.464999 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KU222 UT WOS:A1993KU22200006 ER PT J AU ZAFIROPULOS, V KOLLIA, Z FOTAKIS, C STOCKDALE, JAD AF ZAFIROPULOS, V KOLLIA, Z FOTAKIS, C STOCKDALE, JAD TI LASER-INDUCED MICRON SIZE CLUSTERING IN THIOPHENOL VAPOR SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CARBON-DISULFIDE; NUCLEATION; PARTICLES; POWDERS AB Positively charged micron sized clusters are efficiently produced following irradiation of thiophenol vapor at 248 nm by a single KrF laser pulse of 30 ns duration. The production mechanism has been studied by examining the effect of N2, Ar, and He as diffusion media in mixtures with thiophenol, and by varying the laser pulse energy and excitation wavelength. A qualitative summary of possible mechanisms that may be responsible for the experimental results is presented providing a framework for understanding the observed cluster growth. The measurements indicate an optimum set of parameters for growth of large clusters and also show that the cluster charge can be controlled by selection of the buffer gas mixture. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. UNIV CRETE,DEPT CHEM,IRAKLION,GREECE. UNIV CRETE,DEPT PHYS,IRAKLION,GREECE. RP ZAFIROPULOS, V (reprint author), FORTH,INST ELECTR STRUCT & LASER,POB 1527,GR-71110 IRAKLION,GREECE. RI Fotakis, Costas/G-8751-2011 NR 37 TC 1 Z9 1 U1 0 U2 2 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 MAR 15 PY 1993 VL 98 IS 6 BP 5079 EP 5086 DI 10.1063/1.464963 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KU222 UT WOS:A1993KU22200080 ER PT J AU KRESS, JD AF KRESS, JD TI ACCURATE 3-DIMENSIONAL QUANTUM SCATTERING CALCULATIONS FOR THE F+H2 REACTION ON A NEW POTENTIAL-ENERGY SURFACE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Note ID MECHANICAL REACTION PROBABILITIES; TRANSITION-STATE THEORY; D2 RP KRESS, JD (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,T-12,MS B268,LOS ALAMOS,NM 87545, USA. NR 14 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 15 PY 1993 VL 98 IS 6 BP 5106 EP 5107 DI 10.1063/1.464936 PG 2 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KU222 UT WOS:A1993KU22200087 ER PT J AU BRIZARD, C RODRICKS, B ALP, E MACHARRIE, R AF BRIZARD, C RODRICKS, B ALP, E MACHARRIE, R TI INSITU X-RAY-DIFFRACTION OF THE EARLY STAGES OF THE CRYSTALLIZATION OF FE80B20 SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB A new technique has been used for the early stages of crystallization of amorphous materials, like metallic alloys. In situ X-ray diffraction has been performed during the early stages of crystallization of Fe80B20. The samples are resistively heated to 600-degrees-C in a customized vacuum chamber. A programmable charge-coupled device detector records simultaneously the evolution of the three phases: alpha-Fe, Fe3B and Fe2B in the minute scale. This is the first in situ X-ray diffraction study of this system in these temperature and time scales. Interesting behaviours have been seen: appearance and disappearance of phases, alpha-Fe supersaturation solution in boron (found for the first time in this compound), and migration of B out of the alpha-Fe matrix. The two-dimensional diffraction pictures show topography irregularities indicating crystallite inhomogeneties. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. RP BRIZARD, C (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 15 TC 4 Z9 4 U1 1 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 MAR 15 PY 1993 VL 28 IS 6 BP 1503 EP 1508 DI 10.1007/BF00363340 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA KV372 UT WOS:A1993KV37200008 ER PT J AU SHALZ, ML DALGLEISH, BJ TOMSIA, AP GLAESER, AM AF SHALZ, ML DALGLEISH, BJ TOMSIA, AP GLAESER, AM TI CERAMIC JOINING .1. PARTIAL TRANSIENT LIQUID-PHASE BONDING OF ALUMINA VIA CU/PT INTERLAYERS SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID SILICON-NITRIDE; COPPER; SAPPHIRE AB A method of ceramic-ceramic joining that exploits a thin layer of a transient liquid phase to join alumina to alumina has been developed, and the results of its application to joining alumina are reported. Through the use of microdesigned multilayer Cu/Pt interlayers, transient liquid-phase joining has been achieved at 1150-degrees-C, yielding an interlayer that is platinum-rich at temperatures substantially lower than those required for solid-state diffusion bonding with pure platinum interlayers. Flexure tests indicate that ceramic/metal interface strengths exceeding those of the ceramic can be achieved. Post-bonding anneals of 10 h duration in air and gettered argon at 1 000-degrees-C had discernibly different effects on room-temperature joint strength. The microstructure and chemistry of fracture surfaces were examined using SEM and EDS in an effort to identify the nature of strength-limiting flaws in both as-bonded and post-bonding annealed specimens. Topics requiring further study are identified. Opportunities for extensions of the method to other systems are discussed. C1 UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720. RP SHALZ, ML (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720, USA. NR 34 TC 56 Z9 57 U1 3 U2 10 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 MAR 15 PY 1993 VL 28 IS 6 BP 1673 EP 1684 DI 10.1007/BF00363367 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA KV372 UT WOS:A1993KV37200035 ER PT J AU MCNEIL, LE GRIMSDITCH, M AF MCNEIL, LE GRIMSDITCH, M TI ELASTIC-MODULI OF MUSCOVITE MICA SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article AB We have used Brillouin scattering to measure the thirteen independent elastic moduli of muscovite mica. The moduli reflect the monoclinic symmetry of the crystal, and demonstrate the anisotropy of the interlayer and intralayer bonding. The decrease in the acoustic velocity with increasing temperature is dominated by the decrease in the moduli that depend on interlayer bonding, giving an estimate of the temperature dependence of those moduli. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP MCNEIL, LE (reprint author), UNIV N CAROLINA,DEPT PHYS & ASTRON,CHAPEL HILL,NC 27599, USA. NR 19 TC 82 Z9 82 U1 1 U2 15 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD MAR 15 PY 1993 VL 5 IS 11 BP 1681 EP 1690 DI 10.1088/0953-8984/5/11/008 PG 10 WC Physics, Condensed Matter SC Physics GA KT278 UT WOS:A1993KT27800008 ER PT J AU ROLES, KA WUNDERLICH, B AF ROLES, KA WUNDERLICH, B TI HEAT-CAPACITIES OF SOLID COPOLY (AMINOACID)S SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE HEAT CAPACITY; ENTHALPY; ENTROPY; GIBBS FUNCTION; POLY(L-LYSINE HBR-ALANINE); POLY(L-LYSINE HBR-PHENYLALANINE); POLY(SODIUM-L-GLUTAMATE-TYROSINE); POLY(L-PROLINE-GLYCINE-PROLINE); VIBRATIONAL SPECTRA ID CARBON BACKBONE POLYMERS; LINEAR MACROMOLECULES; THERMODYNAMIC PROPERTIES; THERMAL VARIATIONS; ADDITION SCHEME; POLY(L-VALINE); POLYETHYLENE; POLYGLYCINE; POLYOXIDES AB Recently heat capacities C(p) of poly(amino acid)s of all naturally occurring amino acids have been determined. In a second step the heat capacities of four copoly (amino acid) s are studied in this research. Poly (L-lysine . HBr-alanine), poly (L-Lysine . HBr-phenylalanine), poly (sodium-L-glutamate-tyrosine), and poly (L-proline-glycine-proline) heat capacities are measured by differential scanning calorimetry in the temperature range 230-390 K. This is followed by an analysis using approximate group vibrations and fitting the C(p) contributions of the skeletal vibrations of the corresponding homopolymers to a two-parameter Tarasov function. Good agreement is found between experiment and calculation. Predictions of heat capacities based on homopoly (amino acid) s are thus expected to be possible for all polypeptides, and enthalpies, entropies, and Gibbs functions for the solid state can be derived. C1 UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. RP ROLES, KA (reprint author), OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831, USA. NR 29 TC 13 Z9 13 U1 1 U2 7 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD MAR 15 PY 1993 VL 31 IS 3 BP 279 EP 285 DI 10.1002/polb.1993.090310306 PG 7 WC Polymer Science SC Polymer Science GA KL854 UT WOS:A1993KL85400006 ER PT J AU RYE, R AF RYE, R TI SPECTROSCOPIC EVIDENCE FOR RADIATION-INDUCED CROSS-LINKING OF POLY(TETRAFLUOROETHYLENE) SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE CROSS-LINKING OF POLY(TETRAFLUOROETHYLENE), RADIATION-INDUCED; SPECTROSCOPIC EVIDENCE FOR RADIATION-INDUCED CROSS-LINKING OF PTFE; POLY(TETRAFLUOROETHYLENE), RADIATION-INDUCED CROSS-LINKING OF ID ELECTRON-IRRADIATION; POLYTETRAFLUOROETHYLENE; ADHESION; ESCA AB Direct spectroscopic evidence for radiation-induced crosslinking of poly (tetrafluoroethylene) (PTFE) is presented for all x-ray and electron dose levels above which it is possible to distinguish between deliberately introduced radiation damage and the x-ray damage inherent in obtaining an x-ray photoelectron spectrum (XPS). The C (1s) spectrum obtained after irradiation with 2 keV electrons for all doses greater than 1 muA-min/cm2 consists of a four-peak spectrum identical to that previously obtained for plasma-polymerized tetrafluoroethylene and assigned to carbon atoms with variable numbers of bound F atoms (CF3, CF2, CF1, and CF0). X-ray irradiated PTFE can be fitted with the same four-peak spectrum. At or below an electron dose level of 1 muA-min/cm2, the radiation damage is comparable to that produced by the x-ray dose necessary to obtain an XPS spectrum. The CF1 and CF0 components increase with increasing electron dose, and at high electron doses dominate the spectrum. With increasing dose the CF3 component approaches a constant value while both the CF2 component and the total F : C ratio decreases. These four components are those expected to result from radiation-induced crosslinking reactions of the polymer and are consistent with previous suggestions that crosslinking is the basis of radiation patterned adhesion to PTFE. RP RYE, R (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 17 TC 31 Z9 31 U1 0 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD MAR 15 PY 1993 VL 31 IS 3 BP 357 EP 364 DI 10.1002/polb.1993.090310314 PG 8 WC Polymer Science SC Polymer Science GA KL854 UT WOS:A1993KL85400014 ER PT J AU BATES, JB DUDNEY, NJ GRUZALSKI, GR ZUHR, RA CHOUDHURY, A LUCK, CF ROBERTSON, JD AF BATES, JB DUDNEY, NJ GRUZALSKI, GR ZUHR, RA CHOUDHURY, A LUCK, CF ROBERTSON, JD TI FABRICATION AND CHARACTERIZATION OF AMORPHOUS LITHIUM ELECTROLYTE THIN-FILMS AND RECHARGEABLE THIN-FILM BATTERIES SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL MEETING ON LITHIUM BATTERIES ( 6-IMLB ) CY MAY 10-15, 1992 CL MUNSTER, GERMANY SP DEUT AKAD AUSTAUSCHDIENST, DEUT FORSCHUNGSGEMEINSCH, MINIST FORSCH & WISSENSCH LANDES NORDRHEINWESTFALEN, UNIV MUNSTER, GRACE, PRIVATBRAUEREI A ROLINCK, RENATA BATTERIES, SONNENSCHEIN LITHIUM, VARTA BATTERIE ID SPECTROSCOPY; V2O5 AB Amorphous oxide and oxynitride lithium electrolyte thin films were synthesized by r.f. magnetron sputtering of lithium silicates and lithium phosphates in Ar, Ar+O2, Ar+N2, or N2. The composition, structure, and electrical properties of the films were characterized using ion and electron beam, X-ray, optical, photoelectron, and a.c. impedance techniques. For the lithium phosphosilicate films, lithium ion conductivities as high as 1.4x10(-6) S/cm at 25-degrees-C were observed, but none of these films selected for extended testing were stable in contact with lithium. On the other hand, a new thin-film lithium phosphorus oxynitride electrolyte, synthesized by sputtering Li3PO4 in pure N2, was found to have a conductivity of 2x10(-6) S/cm at 25-degrees-C and excellent long-term stability in contact with lithium. Thin-films cells consisting of a 1 mum thick amorphous V2O5 cathode, a 1 mum thick oxynitride electrolyte film, and a 5 mum thick lithium anode were cycled between 3.7 and 1.5 V using discharge rates of up to 100 muA/cm2 and charge rates of up to 20 muA/cm2. The open-circuit voltage of 3.6 to 3.7 V of fully-charged cells remained virtually unchanged after months of storage. C1 UNIV KENTUCKY,DEPT CHEM,LEXINGTON,KY 40506. RP BATES, JB (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37830, USA. RI Dudney, Nancy/I-6361-2016 OI Dudney, Nancy/0000-0001-7729-6178 NR 15 TC 253 Z9 263 U1 23 U2 152 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD MAR 15 PY 1993 VL 43 IS 1-3 BP 103 EP 110 DI 10.1016/0378-7753(93)80106-Y PG 8 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA LH762 UT WOS:A1993LH76200012 ER PT J AU LEVY, SC AF LEVY, SC TI SAFETY AND RELIABILITY STUDIES OF PRIMARY LITHIUM BATTERIES SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL MEETING ON LITHIUM BATTERIES ( 6-IMLB ) CY MAY 10-15, 1992 CL MUNSTER, GERMANY SP DEUT AKAD AUSTAUSCHDIENST, DEUT FORSCHUNGSGEMEINSCH, MINIST FORSCH & WISSENSCH LANDES NORDRHEINWESTFALEN, UNIV MUNSTER, GRACE, PRIVATBRAUEREI A ROLINCK, RENATA BATTERIES, SONNENSCHEIN LITHIUM, VARTA BATTERIE AB The safety and reliability of batteries are closely related. Examples are given to demonstrate how changes made in battery materials and design parameters to improve either safety or reliability may also enhance other characteristics. In one example, replacement of the glass in the glass-to-metal seal of Li/SO2 cells to improve reliability also eliminated a serious safety problem associated with discharged cells. The second example relates to design parameters in Li/SOCl2 cells for increased safety. A Taguchi analysis indicated several parameters affected safety upon reversal. The indicated levels of these parameters for improved safety also suggest improved reliability, although the long-term reliability studies have not yet been completed. RP LEVY, SC (reprint author), SANDIA NATL LABS,DIV EXPLORATORY BATTERIES,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD MAR 15 PY 1993 VL 43 IS 1-3 BP 247 EP 251 DI 10.1016/0378-7753(93)80121-5 PG 5 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA LH762 UT WOS:A1993LH76200027 ER PT J AU GORETTA, KC THOMPSON, AC ROUTBORT, JL AF GORETTA, KC THOMPSON, AC ROUTBORT, JL TI EROSION OF HEAT-TREATED AISI 4140 STEEL SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Letter ID DUCTILE METALS AB Solid-particle erosion was studied on AISI 4140 steel heat treated to have a Vickers hardness (Hv) of 288-650 kg mm-2. The experiments were conducted in vacuum with 143 mum Al2O3 abrasive impacting at 50-1 00 m s-1 at an angle of 30-degrees or 90-degrees. Erosion rates were nearly independent of hardness for Hv less-than-or-equal-to 365 kg MM-2, but increased with hardness for Hv > 365 kg mm-2. The improved erosion resistances of the softer alloys were attributed to increased ductilities. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP GORETTA, KC (reprint author), ARGONNE NATL LAB,DIV MAT & COMPONENTS TECHNOL,ARGONNE,IL 60439, USA. NR 16 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 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD MAR 15 PY 1993 VL 161 IS 1 BP L7 EP L10 DI 10.1016/0921-5093(93)90488-Z PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA KT461 UT WOS:A1993KT46100020 ER PT J AU HSUEH, CH AF HSUEH, CH TI INTERFACIAL DEBONDING AND FIBER PULL-OUT STRESSES OF FIBER-REINFORCED COMPOSITES .9. A SIMPLE TREATMENT OF POISSON EFFECT FOR FRICTIONAL INTERFACES SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Letter ID CERAMIC-MATRIX; SHEAR-STRESS; INDENTATION; RESISTANCE; STRENGTH AB Consideration of Poisson's effect is essential in modeling a debonded fiber-matrix interface, which is subjected to Coulomb friction during fiber pull-out. The stress analysis is formidable when Poisson's effect is considered pointwise along the sliding length. In the present study, Poisson's effect is treated in an average sense, and both the stress analysis and the analytical solutions for fiber pull-out are greatly simplified. Applications of this averaging technique to fiber push-out and indentation problems are also addressed. The simplified solutions obtained in the present study are in excellent agreement with the previous more rigorous, complex solutions, but are more tractable than the rigorous solutions. RP HSUEH, CH (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831, USA. RI Hsueh, Chun-Hway/G-1345-2011 NR 16 TC 19 Z9 19 U1 2 U2 8 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 MAR 15 PY 1993 VL 161 IS 1 BP L1 EP L6 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA KT461 UT WOS:A1993KT46100019 ER PT J AU DITMIRE, T PERRY, MD AF DITMIRE, T PERRY, MD TI TERAWATT CR-LISRALF6 LASER SYSTEM SO OPTICS LETTERS LA English DT Article ID CHIRPED-PULSE AMPLIFICATION; ND-GLASS LASER; GENERATION AB We have developed a compact flash-lamp-pumped Cr:LiSrAlF6 (Cr:LiSAF) laser system capable of producing peak powers in excess of 1 TW. Chirped-pulse amplification in a Cr:LiSAF regenerative amplifier produces 8-mJ pulses at a 5-Hz repetition rate. Further amplification in Cr:LiSAF yields recompressed pulse energies of 150 mJ and a pulse duration <135 fs at a 0.5-Hz repetition rate. RP DITMIRE, T (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,L-395,LIVERMORE,CA 94550, USA. NR 17 TC 46 Z9 46 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAR 15 PY 1993 VL 18 IS 6 BP 426 EP 428 DI 10.1364/OL.18.000426 PG 3 WC Optics SC Optics GA KP967 UT WOS:A1993KP96700010 PM 19802157 ER PT J AU ROBERTS, JP HOSACK, KW TAYLOR, AJ WESTON, J ETTELBRICK, RN AF ROBERTS, JP HOSACK, KW TAYLOR, AJ WESTON, J ETTELBRICK, RN TI EFFICIENT FREQUENCY-DOUBLED LONG-PULSE GENERATION WITH A ND-GLASS/ND-YAG OSCILLATOR AMPLIFIER SYSTEM SO OPTICS LETTERS LA English DT Article ID LASER AB A laser system based on a Nd:glass oscillator followed by a series of Nd:YAG amplifiers is described. The two-beam energy output is 2.2 J in 85 ns at 1.06 mum. The output is efficiently frequency doubled in KD*P to yield 1.04-J, 110-ns, 0.532-mum pulses at a 5-Hz repetition rate. C1 CONTINUUM INC,SANTA CLARA,CA 95051. RP ROBERTS, JP (reprint author), LOS ALAMOS NATL LAB,DIV CHEM & LASER SCI,MS E543,LOS ALAMOS,NM 87545, USA. NR 11 TC 4 Z9 4 U1 1 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAR 15 PY 1993 VL 18 IS 6 BP 429 EP 431 DI 10.1364/OL.18.000429 PG 3 WC Optics SC Optics GA KP967 UT WOS:A1993KP96700011 PM 19802158 ER PT J AU GRAY, JA GOLDSMITH, JEM TREBINO, R AF GRAY, JA GOLDSMITH, JEM TREBINO, R TI DETECTION OF ATOMIC-HYDROGEN BY 2-COLOR LASER-INDUCED GRATING SPECTROSCOPY SO OPTICS LETTERS LA English DT Article ID FLAME; PLASMA; OH AB We report a novel multiphoton scheme for the detection of atomic hydrogen. Interference of two laser beams near 243 nm crossed at a small angle induces a spatially modulated two-photon excitation (i.e., a grating of excited atoms), which diffracts a third laser beam tuned to either 486 or 656 nm to generate a coherent signal beam. We demonstrate the technique by making H-atom concentration measurements that compare quantitatively with those made using laser-induced fluorescence in low-pressure H-2/O2 flames. RP GRAY, JA (reprint author), SANDIA NATL LABS,COMBUST RES FACIL,LIVERMORE,CA 94551, USA. NR 16 TC 28 Z9 28 U1 0 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAR 15 PY 1993 VL 18 IS 6 BP 444 EP 446 DI 10.1364/OL.18.000444 PG 3 WC Optics SC Optics GA KP967 UT WOS:A1993KP96700016 PM 19802163 ER PT J AU MCNAMARA, G ALDER, B AF MCNAMARA, G ALDER, B TI ANALYSIS OF THE LATTICE BOLTZMANN TREATMENT OF HYDRODYNAMICS SO PHYSICA A LA English DT Article; Proceedings Paper CT 18TH INTERNATIONAL CONF ON STATISTICAL PHYSICS ( STATPHYS-18 ) CY AUG 02-08, 1992 CL TECH UNIV BERLIN, BERLIN, GERMANY SP INT UNION PURE & APPL PHYS HO TECH UNIV BERLIN ID GAS AUTOMATA; EQUATION; FLOW AB It is shown that the lattice-Boltzmann model can be made to obey the three-dimensional thermal Navier-Stokes equations by fixing 26 moments of the equilibrium distribution function. This can be achieved on a cubic lattice with particle velocities connecting each lattice site to its first, second and third nearest neighbors; however, this minimal model is not linearly stable in the limit of low transport coefficients. Additional particle velocities must be selected to achieve linear stability. RP MCNAMARA, G (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 13 TC 125 Z9 130 U1 1 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD MAR 15 PY 1993 VL 194 IS 1-4 BP 218 EP 228 DI 10.1016/0378-4371(93)90356-9 PG 11 WC Physics, Multidisciplinary SC Physics GA KU620 UT WOS:A1993KU62000022 ER PT J AU HOOVER, WG AF HOOVER, WG TI NONEQUILIBRIUM MOLECULAR-DYNAMICS - THE 1ST 25 YEARS SO PHYSICA A LA English DT Article; Proceedings Paper CT 18TH INTERNATIONAL CONF ON STATISTICAL PHYSICS ( STATPHYS-18 ) CY AUG 02-08, 1992 CL TECH UNIV BERLIN, BERLIN, GERMANY SP INT UNION PURE & APPL PHYS HO TECH UNIV BERLIN ID CAR-PARRINELLO APPROACH; EFFECTIVE POTENTIALS; TRANSPORT PROCESSES; SHEAR VISCOSITY; EQUILIBRIUM; MECHANICS AB Equilibrium molecular dynamics has been generalized to simulate nonequilibrium systems by adding sources of thermodynamic heat and work. This generalization incorporates microscopic mechanical definitions of macroscopic thermodynamic and hydrodynamic variables, such as temperature and stress, and augments atomistic forces with special boundary, constraint and driving forces capable of doing work on, and exchanging heat with, an otherwise Newtonian system: p = F(A)(q) + F(B)(q) + F(C)(q,p) + F(D)(q,p) = m(q(t+dt) - 2q(t) + q(t-dt))/dt2. The underlying Lyapunov instability of these nonequilibrium equations of motion links microscopic time-reversible deterministic trajectories to macroscopic time-irreversible hydrodynamic behavior as described by the second law of thermodynamics. Green-Kubo linear-response theory has been checked. Nonlinear plastic deformation, intense heat conduction, shock-wave propagation, and nonequilibrium phase transformation have all been simulated. The nonequilibrium techniques, coupled with qualitative improvements in parallel computer hardware, are enabling simulations to approximate real-world microscale and nanoscale experiments. C1 LAWRENCE LIVERMORE NATL LAB,DEPT PHYS,LIVERMORE,CA 94551. RP HOOVER, WG (reprint author), UNIV CALIF DAVIS LIVERMORE,DEPT APPL SCI,LIVERMORE,CA 94551, USA. NR 43 TC 27 Z9 27 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD MAR 15 PY 1993 VL 194 IS 1-4 BP 450 EP 461 DI 10.1016/0378-4371(93)90376-F PG 12 WC Physics, Multidisciplinary SC Physics GA KU620 UT WOS:A1993KU62000042 ER PT J AU VIOLET, CE BEDFORD, RG WINTER, NW SMITH, GS MEI, Z DURST, MJ WU, JK AF VIOLET, CE BEDFORD, RG WINTER, NW SMITH, GS MEI, Z DURST, MJ WU, JK TI FE-57 MOSSBAUER SPECTROMETRY AND THERMOGRAVIMETRY OF THE HIGH-TC SUPERCONDUCTOR HOBA2(CU0.95FE0.05)3O7.02 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; NUCLEAR-QUADRUPOLE RESONANCE; ELECTRIC-FIELD GRADIENTS; STRUCTURAL-PROPERTIES; PRESSURE-DEPENDENCE; THERMAL TREATMENTS; CU SUBSTITUTION; SINGLE-CRYSTALS; MAGNETIC ORDER; FE AB The high-T(c) superconductor HoBa2(Cu0.95Fe0.05)3O7.02 was studied by thermogravimetry and Mossbauer spectrometry. The oxygen stoichiometry of the Mossbauer sample as determined by reduction with a mixture of nitrogen and hydrogen was 7.02 +/- 0.01. The quadrupole splitting, isomer shift, line width, maximum resonance absorption, relative intensity, and \V(zz)(1 + eta2/3)1/2\ associated with the 6-doublet and 7-doublet fits are reported. The Fe valence state associated with the doublet with the smallest quadrupole splitting (and largest positive isomer shift) is high spin ferric. The valence state associated with the remaining doublets, corresponding to 90% of the substituted Fe, is best described as high spin Fe with a formal charge of + 4, the so-called ''high spin Fe4+'' state. The number of non-equivalent Fe sites is most likely six. The possibility of a seventh site is not ruled out; the possibility of eight or more sites is. The quadrupole splittings, isomer shifts, and line widths of the high spin Fe4+ doublets are strongly correlated suggesting that relaxation effects may be operative. C1 LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. RP LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. NR 78 TC 1 Z9 1 U1 0 U2 1 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 MAR 15 PY 1993 VL 207 IS 3-4 BP 347 EP 358 DI 10.1016/0921-4534(93)90317-J PG 12 WC Physics, Applied SC Physics GA KT694 UT WOS:A1993KT69400018 ER PT J AU STADLER, PF FONTANA, W MILLER, JH AF STADLER, PF FONTANA, W MILLER, JH TI RANDOM CATALYTIC REACTION NETWORKS SO PHYSICA D LA English DT Article ID DYNAMICS AB We study networks that are a generalization of replicator (or Lotka-Volterra) equations. They model the dynamics of a population of object types whose binary interactions determine the specific type of interaction product. Such a system always reduces its dimension to a subset that contains production pathways for all of its members. The network equation can be be rewritten at a level of collectives in terms of two basic interaction patterns: replicator sets and cyclic transformation pathways among sets. Although the system contains well-known cases that exhibit very complicated dynamics, the generic behavior of randomly generated systems is found (numerically) to be extremely robust: convergence to a globally stable rest point. It is easy to tailor networks that display replicator interactions where the replicators are entire self-sustaining subsystems, rather than structureless units. A numerical scan of random systems highlights the special properties of elementary replicators: they reduce the effective interconnectedness of the system, resulting in enhanced competition, and strong correlations between the concentrations. C1 SANTA FE INST,1660 OLD PECOS TRAIL,SANTA FE,NM 87501. UNIV VIENNA,INST THEORET CHEM,A-1090 VIENNA,AUSTRIA. LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. CARNEGIE MELLON UNIV,PITTSBURGH,PA 15213. RI Stadler, Peter F./L-7857-2015 OI Stadler, Peter F./0000-0002-5016-5191 NR 27 TC 44 Z9 46 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD MAR 15 PY 1993 VL 63 IS 3-4 BP 378 EP 392 DI 10.1016/0167-2789(93)90118-K PG 15 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KV393 UT WOS:A1993KV39300009 ER PT J AU ICE, GE ISAACS, E ZSCHACK, P AF ICE, GE ISAACS, E ZSCHACK, P TI SPLITTING OF RESONANT RAMAN X-RAY PEAKS NEAR THE MIV AND MV EDGES OF URANIUM SO PHYSICAL REVIEW B LA English DT Article ID SYNCHROTRON RADIATION; EXCHANGE SCATTERING; MAGNETIC SCATTERING; SPECTROSCOPY; EMISSION; URU2SI2; METALS; FLUORESCENCE; ELECTRON; STATES AB Resonant Raman x-ray-scattering spectra have been measured at 1 eV resolution with the incident x-ray energy tuned near the uranium M(IV) and M(V) absorption edges. Measurements were made on a single crystal of URu2Si2. Inelastic x-ray spectra were collected within +/- 30 eV of the U M(IV)(3d 3/2)-N(VI)(4f 5/2) and the U M(V)(3d 5/2)-N(VII)(4f 7/2) x-ray-emission lines. The incident beam was tuned through the M(IV) and M(V) threshold energies. At both edges the emission spectra are dominated by three lines: a diagram line (corresponding to the promotion of an electron to the continuum), a large spectator line (arising from the promotion of an electron into a pre-edge band), and a smaller companion spectator line. The spectator lines exhibit linear dispersion as a function of the incident x-ray energy and the spectator lines have resonances approximately 4 eV below the continuum thresholds. At the U M(IV) edge, the large spectator line is assigned to the M(IV)-N(VI) transition. The small spectator line has an x-ray energy about 7 eV higher, which is 3 eV below the forbidden M(IV)-N(VII) line. At the U M(V) edge the main spectator line is assigned to the M(V)-N(VII) transition with a smaller peak 10 eV lower near the M(V)-N(VI) position. The intensity of the small Mv spectator line relative to the M(V)-N(VII) spectator line is much larger than the diagram line ratio of M(V)-N(VI)/M(V)-N(VII) observed with nonresonant electron-excited spectra. The emission spectra were corrected for resonance enhancement to study the coupling of the 3d (3/2) and 3d (5/2) electrons to the near-edge density of unoccupied states. The near-edge, or ''white-line,'' feature at the M(V) edge is found to be flat topped, while the near-edge feature at the M(IV) edge is asymmetric and peaked. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. OAK RIDGE ASSOCIATED UNIV,OAK RIDGE,TN 37830. RP ICE, GE (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831, USA. NR 53 TC 6 Z9 6 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 MAR 15 PY 1993 VL 47 IS 11 BP 6241 EP 6249 DI 10.1103/PhysRevB.47.6241 PG 9 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200007 ER PT J AU JAFFE, JE PANDEY, R SEEL, MJ AF JAFFE, JE PANDEY, R SEEL, MJ TI ABINITIO HIGH-PRESSURE STRUCTURAL AND ELECTRONIC-PROPERTIES OF ZNS SO PHYSICAL REVIEW B LA English DT Article ID PHASE-TRANSITION; TETRAHEDRAL COMPOUNDS; III-V; STATE; SEMICONDUCTORS; EQUATION; DIAMOND; SOLIDS AB The total energy of ZnS as a function of unit-cell volume has been calculated for the zinc-blende and rocksalt structures by the first-principles Hartree-Fock linear-combination-of-atomic-orbitals method. The calculated structural properties of both phases and the transition pressure between them agree very well with experiment. The band structure of the high-pressure phase is obtained and discussed in relation to zinc-blende ZnS and other IIB-VIA semiconductors. C1 MICHIGAN TECHNOL UNIV, DEPT PHYS, HOUGHTON, MI 49931 USA. RP JAFFE, JE (reprint author), PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. NR 22 TC 60 Z9 65 U1 1 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 MAR 15 PY 1993 VL 47 IS 11 BP 6299 EP 6303 DI 10.1103/PhysRevB.47.6299 PG 5 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200012 ER PT J AU MIYANO, KE WOICIK, JC KENDELEWICZ, T SPICER, WE RICHTER, M PIANETTA, P AF MIYANO, KE WOICIK, JC KENDELEWICZ, T SPICER, WE RICHTER, M PIANETTA, P TI SURFACE EXTENDED X-RAY-ABSORPTION FINE-STRUCTURE STUDY OF THE (1 MONOLAYER SB) GAP(110) INTERFACE SO PHYSICAL REVIEW B LA English DT Article ID ENERGY-ELECTRON-DIFFRACTION; DYNAMICAL ANALYSIS; 110 SURFACES; PHOTOEMISSION; SPECTROSCOPY; OVERLAYERS; SEMICONDUCTORS; INTENSITIES; AMPLITUDE; SI(111) AB Sb L-edge absorption fine structure has been measured to study the bonding geometry of the (1 monolayer Sb)/GaP(110) interface. The polarization dependence of these measurements confirms that the Sb zigzag chains lie nearly parallel to the GaP surface. The Sb-P, Sb-Ga, and Sb-Sb bond lengths are determined to be 2.60+/-0.05, 2.79+/-0.05, and 2.88+/-0.05 angstrom, respectively. These values are better characterized by sums of covalent radii than by bond lengths determined in total-energy-minimization calculations. C1 STANFORD UNIV,STANFORD ELECTR LABS,STANFORD,CA 94305. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94305. NR 23 TC 11 Z9 11 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 MAR 15 PY 1993 VL 47 IS 11 BP 6444 EP 6449 DI 10.1103/PhysRevB.47.6444 PG 6 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200030 ER PT J AU HONG, H ABURANO, RD HIRSCHORN, ES ZSCHACK, P CHEN, H CHIANG, TC AF HONG, H ABURANO, RD HIRSCHORN, ES ZSCHACK, P CHEN, H CHIANG, TC TI INTERACTION OF (1X2)-RECONSTRUCTED SI(100) AND AG(110) - CS SURFACES WITH C-60 OVERLAYERS SO PHYSICAL REVIEW B LA English DT Article ID SI(001); DIFFRACTION AB The structure of the Si(100)-(1 X 2) surface, after room-temperature deposition of a thin film of C60, has been examined with grazing-incidence synchrotron x-ray diffraction. The (1 X 2) surface reconstruction is well preserved under the C60 overlayer. The measured fractional-order diffraction intensities, similar to those reported for the clean Si(100)-(1 X 2) surface, are analyzed in terms of a dimer model. A similar investigation has been carried out for another (1 X 2) reconstructed surface, a Cs-doped Ag(110), to test the generality of the preservation of surface reconstructions under a C60 cap layer. In this case, the (1 X 2) reconstruction is suppressed by the deposition of C60. C1 UNIV ILLINOIS,MAT RES LAB,URBANA,IL 61801. UNIV ILLINOIS,DEPT MAT SCI & ENGN,URBANA,IL 61801. OAK RIDGE INST SCI & EDUC,DIV MET & CERAM,OAK RIDGE,TN 37831. UNIV ILLINOIS,DEPT PHYS,URBANA,IL 61801. RI Chiang, Tai/H-5528-2011 NR 16 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 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1993 VL 47 IS 11 BP 6450 EP 6454 DI 10.1103/PhysRevB.47.6450 PG 5 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200031 ER PT J AU GODIN, TJ LAFEMINA, JP AF GODIN, TJ LAFEMINA, JP TI SURFACE ATOMIC AND ELECTRONIC-STRUCTURE OF CASSITERITE SNO2 (110) SO PHYSICAL REVIEW B LA English DT Article ID PHOTOEMISSION; SNO2(110); OXIDE AB Using a tight-binding, total-energy model, we have calculated relaxed surface atomic positions, surface-state energies, and densities of states for the reduced and stoichiometric (110) surfaces of rutile-structure tin dioxide (cassiterite). Both relaxed surfaces display a small rumple of the top atomic layer and smaller counter-rumples of the subsurface layers. The surface-state energy lowering caused by the relaxation is small because of the surface topology, which forbids bond-length-conserving motions of the surface atoms. The density of states for the reduced surface agrees qualitatively with photoemission data that indicate the absence of surface states in the fundamental gap of the material. RP GODIN, TJ (reprint author), PACIFIC NW LAB, MOLEC SCI RES CTR, POB 999, RICHLAND, WA 99352 USA. NR 23 TC 63 Z9 65 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 MAR 15 PY 1993 VL 47 IS 11 BP 6518 EP 6523 DI 10.1103/PhysRevB.47.6518 PG 6 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200039 ER PT J AU LEE, I CALLCOTT, TA ARAKAWA, ET AF LEE, I CALLCOTT, TA ARAKAWA, ET TI DESORPTION STUDIES OF METAL ATOMS USING LASER-INDUCED SURFACE-PLASMON EXCITATION SO PHYSICAL REVIEW B LA English DT Article ID NONRESONANT MULTIPHOTON IONIZATION; SIZE MANIPULATION; PARTICLES; LIGHT; ABLATION; EMISSION; SPECTRA AB Au, Al, and Ag atoms have been desorbed from thin films on glass by laser-excited surface plasmons in an attenuated-total-reflection geometry. Desorption yields are measured as a function of angle of incidence near the optimum coupling angle and the kinetic energies of desorbed neutral atoms are determined. A linear dependence of desorption yield on photon intensities and the presence of high-kinetic-energy atoms suggest that the major desorption mechanism is a nonthermal electronic process. Possible desorption processes are discussed. C1 UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. RP LEE, I (reprint author), OAK RIDGE NATL LAB,DIV HLTH & SAFETY RES,OAK RIDGE,TN 37831, USA. NR 28 TC 35 Z9 35 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 MAR 15 PY 1993 VL 47 IS 11 BP 6661 EP 6666 DI 10.1103/PhysRevB.47.6661 PG 6 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200056 ER PT J AU HAO, YG ERIKSSON, O FERNANDO, GW COOPER, BR AF HAO, YG ERIKSSON, O FERNANDO, GW COOPER, BR TI SURFACE ELECTRONIC-STRUCTURE OF GAMMA-URANIUM SO PHYSICAL REVIEW B LA English DT Article ID TRANSITION-METALS; NOBLE AB It is interesting to study the surface electronic structure of uranium in the context of f-electron localization as the 5f shell is filled. Accordingly, we have used the film-linearized-muffin-tin-orbital method to calculate the surface electronic structure of gamma-uranium with body-centered-cubic structure. This all-electron self-consistent fully relativistic calculation has been done for a five-layer slab with (100) surface using two lattice constants (differing by about 1%) corresponding to different experimental information. Our calculated work functions of 3.60 and 3.82 eV for the two lattice constants both provide excellent agreement with the experimental results, which range from 3.63 to 3.90 eV. The calculated density of states and the charge distribution show stronger hybridization of 5f with 6d electrons than that of delta-plutonium. Our calculations indicate that the surface enhancement of 5f localization (i.e., relative to the bulk behavior) is much stronger for uranium than for plutonium. This increase of localization at the surface may have important consequences for surface reconstruction, chemisorption, and other surface behavior. C1 LOS ALAMOS NATL 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 19 TC 15 Z9 16 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 MAR 15 PY 1993 VL 47 IS 11 BP 6680 EP 6684 DI 10.1103/PhysRevB.47.6680 PG 5 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200059 ER PT J AU MIGONE, AD ALKHAFAJI, MT VIDALI, G KARIMI, M AF MIGONE, AD ALKHAFAJI, MT VIDALI, G KARIMI, M TI THERMODYNAMIC STUDY OF ARGON FILMS ADSORBED ON BORON-NITRIDE SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-DIFFRACTION; PHYSICAL ADSORPTION; COMPUTER-SIMULATION; MELTING TRANSITION; SUBMONOLAYER AR; MULTILAYER AR; GRAPHITE; KRYPTON; MONOLAYERS; BEHAVIOR AB We have performed a detailed adsorption isotherm study of Ar on BN for temperatures between 65 and 80 K. The isothermal compressibility of the films was obtained from adsorption data. At monolayer coverages, a small isotherm substep is present at melting. We found two isothermal compressibility peaks in the first layer: a sharp peak, corresponding to the melting substep, and a smaller, broader peak that occurs at lower pressures. At multilayer coverages we found reentrant layering occurring in the third and fourth layers of the film. We compare our layering results with predictions for the preroughening transition. We also found a series of small steps in the isotherms between the second and third layers and between the third and fourth layers of the film. These small steps are evidence of individual layer melting for the second and third layers. Our results at monolayer and at multilayer coverages are extensively compared to those found for Ar on graphite. We have also performed calculations of the rare-gas-BN interaction potentials. Our calculations indicate the substrate corrugation is smaller for the rare-gas-BN systems than it is for the same rare gases on graphite. The implications of this result for the possible existence of monolayer-commensurate solids on BN are discussed. C1 SO ILLINOIS UNIV,MOLEC SCI PROGRAM,CARBONDALE,IL 62901. SYRACUSE UNIV,DEPT PHYS,SYRACUSE,NY 13244. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. INDIANA UNIV PENN,DEPT PHYS,INDIANA,PA 15705. RP MIGONE, AD (reprint author), SO ILLINOIS UNIV,DEPT PHYS,CARBONDALE,IL 62901, USA. NR 58 TC 25 Z9 25 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 MAR 15 PY 1993 VL 47 IS 11 BP 6685 EP 6696 DI 10.1103/PhysRevB.47.6685 PG 12 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200060 ER PT J AU SINGH, PP GONIS, A AF SINGH, PP GONIS, A TI EFFECTIVE CLUSTER INTERACTIONS USING THE GENERALIZED PERTURBATION METHOD IN THE ATOMIC-SPHERE APPROXIMATION SO PHYSICAL REVIEW B LA English DT Note ID COHERENT-POTENTIAL-APPROXIMATION; ELECTRONIC-STRUCTURE; SUBSTITUTIONAL ALLOYS; PHASE-STABILITY; 1ST-PRINCIPLES AB We describe the generalized perturbation method in the atomic-sphere approximation (ASA) for calculating the effective cluster interactions. Based on our development of Korringa-Kohn-Rostoker coherent-potential approximation in the ASA [Singh et al., Phys. Rev. B 44, 8578 (1991)], the present approach is the next step towards developing a first-principles method that can be easily applied to describe substitutionally disordered alloys based on simple lattice structures as well as complex lattice structures with low symmetry. To test the accuracy of the ASA results we have calculated the effective pair interactions (EPI) up to fourth-nearest neighbors for the substitutionally disordered Pd0.5V0.5 and Pd0.75Rho0.25 alloys. Our calculated EPI's are in good agreement with the respective muffin-tin results. RP SINGH, PP (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,L-268,LIVERMORE,CA 94550, USA. NR 16 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 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1993 VL 47 IS 11 BP 6744 EP 6746 DI 10.1103/PhysRevB.47.6744 PG 3 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200069 ER PT J AU GARCIA, A COHEN, ML AF GARCIA, A COHEN, ML TI EFFECT OF GA 3D STATES ON THE STRUCTURAL-PROPERTIES OF GAAS AND GAP SO PHYSICAL REVIEW B LA English DT Note ID V ZINCBLENDE SEMICONDUCTORS; HIGH-PRESSURE PHASES; GALLIUM-ARSENIDE; PSEUDOPOTENTIALS; TRANSITIONS AB It is shown that recent experimental data on the phase diagrams of GaAs and GaP can be reconciled with the results of pseudopotential total-energy calculations if core corrections for exchange and correlation axe used. Theoretical results are also given for the very-high-pressure region of the GaAs phase diagram. We predict that a CsCl-type structure should be stable above 125 GPa. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. XEROX CORP,PALO ALTO RES CTR,PALO ALTO,CA 94304. RP GARCIA, A (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 21 TC 38 Z9 38 U1 2 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 MAR 15 PY 1993 VL 47 IS 11 BP 6751 EP 6754 DI 10.1103/PhysRevB.47.6751 PG 4 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200071 ER PT J AU BOUCHARD, AM LUBAN, M AF BOUCHARD, AM LUBAN, M TI SEMICONDUCTOR SUPERLATTICES AS TERAHERTZ GENERATORS SO PHYSICAL REVIEW B LA English DT Note ID HOMOGENEOUS ELECTRIC-FIELD; BLOCH OSCILLATIONS; TIME EVOLUTION AB Avoiding any truncation of the Hamiltonian for independent electrons in both ideal and imperfect superlattices subject to a uniform electric field, we show that dipole radiation in the terahertz range should be detectable for many members of the GaAs/AlxGa1-xAs system. The radition can be attributed to periodic Bloch oscillations in the case of ideal superlattices, and to almost-periodic oscillations, with the dominant frequencies on the order of the Bloch frequency, in the case of imperfect superlattices. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. RP BOUCHARD, AM (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 22 TC 40 Z9 40 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 MAR 15 PY 1993 VL 47 IS 11 BP 6815 EP 6818 DI 10.1103/PhysRevB.47.6815 PG 4 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200088 ER PT J AU KAWAMOTO, EH LEE, S PERSHAN, PS DEUTSCH, M MASKIL, N OCKO, BM AF KAWAMOTO, EH LEE, S PERSHAN, PS DEUTSCH, M MASKIL, N OCKO, BM TI X-RAY REFLECTIVITY STUDY OF THE SURFACE OF LIQUID GALLIUM SO PHYSICAL REVIEW B LA English DT Note AB X-ray reflectivity from the surface of liquid gallium was measured under ultrahigh vacuum conditions using a novel technique for curved surfaces. The small deviations between the measured and theoretical Fresnel reflectivity for an ideally sharp flat interface for wave-vector transfer less-than-or-similar-to 0.5 angstrom-1 imply an interfacial width for the electron density profile of less-than-or-similar-to 1.3+/-0.2 angstrom. This is consistent with a model of atomic close packing which lacks structure along the surface normal at length scales > 10 angstrom. C1 HARVARD UNIV,DEPT PHYS,CAMBRIDGE,MA 02138. BAR ILAN UNIV,DEPT PHYS,IL-52100 RAMAT GAN,ISRAEL. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP KAWAMOTO, EH (reprint author), HARVARD UNIV,DIV APPL SCI,CAMBRIDGE,MA 02138, USA. NR 12 TC 23 Z9 23 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 MAR 15 PY 1993 VL 47 IS 11 BP 6847 EP 6850 DI 10.1103/PhysRevB.47.6847 PG 4 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200096 ER PT J AU TERMINELLO, LJ BARTON, JJ AF TERMINELLO, LJ BARTON, JJ TI PHOTOELECTRON FORWARD-SCATTERING ATTENUATION FROM THE CU(001) SURFACE SO PHYSICAL REVIEW B LA English DT Note ID EXTENDED-FINE-STRUCTURE; RESOLVED-PHOTOEMISSION; DIFFRACTION; GEOMETRY AB Photoelectron angular distribution patterns from a single-crystal Cu(001) surface have produced dips, or ''silhouettes,'' in the low-energy, electron angular distribution measured around normal emission-a forward-scattering geometry that at higher energy produces a peak, or enhancement, in electron intensity. We have measured isoenergetic l = 1 and l = 2, 0 photoelectrons that give different angular distribution patterns. These differences, and the low-energy electron intensity attenuation, are consistent with an electron scattering model that relies on the orbital angular momentum final-state dependence of the diffracting electron. C1 IBM CORP,THOMAS J WATSON RES CTR,YORKTOWN HTS,NY 10598. RP TERMINELLO, LJ (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 18 TC 3 Z9 3 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 MAR 15 PY 1993 VL 47 IS 11 BP 6851 EP 6854 DI 10.1103/PhysRevB.47.6851 PG 4 WC Physics, Condensed Matter SC Physics GA KT882 UT WOS:A1993KT88200097 ER PT J AU SANCHEZCASTRO, C BEDELL, KS COOPER, BR AF SANCHEZCASTRO, C BEDELL, KS COOPER, BR TI HYBRIDIZATION GAP INSULATING BEHAVIOR OF CE3BI4PT3 SO PHYSICAL REVIEW B LA English DT Article ID MODEL AB We have calculated the temperature dependence of various thermodynamic and transport properties for the N=2 single-band insulating phase of the Anderson lattice Hamiltonian using a slave-boson approach. The conduction band was assumed to be parabolic with a spherical Brillouin-zone boundary. The transport properties were calculated assuming an impurity scattering mechanism and using a relaxation-time approximation. Our calculations demonstrate how many-body effects (on-site Coulomb repulsion) cause an otherwise wide-gap material to behave as a very-narrow-gap material with temperature dependence in qualitative agreement with the experimental data for Ce3Bi4Pt3. This calculation supports the view that this material is an indirect-gap semiconductor. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP SANCHEZCASTRO, C (reprint author), W VIRGINIA UNIV,DEPT PHYS,MORGANTOWN,WV 26506, USA. NR 28 TC 72 Z9 72 U1 2 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 MAR 15 PY 1993 VL 47 IS 12 BP 6879 EP 6884 DI 10.1103/PhysRevB.47.6879 PG 6 WC Physics, Condensed Matter SC Physics GA KV976 UT WOS:A1993KV97600001 ER PT J AU BRANZ, HM ASHER, SE NELSON, BP AF BRANZ, HM ASHER, SE NELSON, BP TI LIGHT-ENHANCED DEEP DEUTERIUM EMISSION AND THE DIFFUSION MECHANISM IN AMORPHOUS-SILICON SO PHYSICAL REVIEW B LA English DT Article ID SI-H AB We demonstrate that hydrogen diffusion in hydrogenated amorphous silicon (a-Si:H) is trap controlled and measure a 1.4-eV barrier for deep deuterium emission to a transport level in D-doped a-Si:H. We show that light-enhanced diffusion in a-Si:H is caused by light-enhanced detrapping of H and not by heating of the sample. From our experiments, we obtain estimates of the free-H-diffusion coefficient (3 X 10(-8) cm2 s-1), the mean H displacement between deep trapping events (250 angstrom), and the other parameters that determine the measured H-diffusion coefficient in a-Si:H. RP BRANZ, HM (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 11 TC 48 Z9 48 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 MAR 15 PY 1993 VL 47 IS 12 BP 7061 EP 7066 DI 10.1103/PhysRevB.47.7061 PG 6 WC Physics, Condensed Matter SC Physics GA KV976 UT WOS:A1993KV97600021 ER PT J AU KEMP, M BRANZ, HM AF KEMP, M BRANZ, HM TI ANALYTIC SOLUTION OF TRAP-CONTROLLED TRACER DIFFUSION IN AMORPHOUS SOLIDS SO PHYSICAL REVIEW B LA English DT Article ID HYDROGEN AB We solve the equations of trap-controlled tracer diffusion in amorphous solids in the case of constant empty-trap density. We show that the early-time tracer profiles develop exponential wings whose widths are given by the mean atomic displacement between trapping events. The wing amplitude increases linearly with time. In the long-time limit, the solutions are identical to the trap-free case, but with an effective diffusion coefficient that can be calculated from features of the early-time tracer profiles. C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. RP KEMP, M (reprint author), UNIV N CAROLINA,DEPT PHYS & ASTRON,CHAPEL HILL,NC 27599, USA. NR 8 TC 27 Z9 27 U1 0 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 MAR 15 PY 1993 VL 47 IS 12 BP 7067 EP 7070 DI 10.1103/PhysRevB.47.7067 PG 4 WC Physics, Condensed Matter SC Physics GA KV976 UT WOS:A1993KV97600022 ER PT J AU DAI, P WANG, SK TAUB, H BUCKLEY, JE EHRLICH, SN LARESE, JZ BINNIG, G SMITH, DPE AF DAI, P WANG, SK TAUB, H BUCKLEY, JE EHRLICH, SN LARESE, JZ BINNIG, G SMITH, DPE TI X-RAY-DIFFRACTION AND SCANNING-TUNNELING-MICROSCOPY STUDIES OF A LIQUID-CRYSTAL FILM ADSORBED ON SINGLE-CRYSTAL GRAPHITE SO PHYSICAL REVIEW B LA English DT Article ID MOLECULES; INTERFACE; DYNAMICS; LAYERS AB Synchrotron x-ray-diffraction and scanning-tunneling-microscopy (STM) experiments reveal a new commensurate monolayer structure of 10CB (decylcyanobiphenyl) molecules adsorbed on the (0001) graphite surface. Our results are consistent with two generic structures for nCB monolayers on surfaces of hexagonal symmetry. The monolayer d spacing of the new phase inferred by STM is 10% larger than that obtained by x-ray diffraction on the same sample. We suggest that part of this discrepancy results from a systematic error introduced in calibration of the STM length scale against the graphite substrate. C1 PURDUE UNIV,SCH MAT ENGN,W LAFAYETTE,IN 47907. BROOKHAVEN NATL LAB,UPTON,NY 11973. IBM CORP,PHYS GRP,W-8000 MUNICH,GERMANY. RP DAI, P (reprint author), UNIV MISSOURI,DEPT PHYS & ASTRON,COLUMBIA,MO 65211, USA. RI Dai, Pengcheng /C-9171-2012 OI Dai, Pengcheng /0000-0002-6088-3170 NR 17 TC 13 Z9 13 U1 1 U2 2 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 MAR 15 PY 1993 VL 47 IS 12 BP 7401 EP 7407 DI 10.1103/PhysRevB.47.7401 PG 7 WC Physics, Condensed Matter SC Physics GA KV976 UT WOS:A1993KV97600055 ER PT J AU MAKOFF, G BARKER, AR BRIERE, RA GIBBONS, LK PAPADIMITRIOU, V PATTERSON, JR SOMALWAR, SV WAH, YW WINSTEIN, B WINSTON, R WOODS, M YAMAMOTO, H SWALLOW, EC BOCK, GJ COLEMAN, R ENAGONIO, J HSIUNG, YB RAMBERG, E STANFIELD, K TSCHIRHART, R YAMANAKA, T GOLLIN, GD KARLSSON, M OKAMITSU, JK DEBU, P PEYAUD, B TURLAY, R VALLAGE, B AF MAKOFF, G BARKER, AR BRIERE, RA GIBBONS, LK PAPADIMITRIOU, V PATTERSON, JR SOMALWAR, SV WAH, YW WINSTEIN, B WINSTON, R WOODS, M YAMAMOTO, H SWALLOW, EC BOCK, GJ COLEMAN, R ENAGONIO, J HSIUNG, YB RAMBERG, E STANFIELD, K TSCHIRHART, R YAMANAKA, T GOLLIN, GD KARLSSON, M OKAMITSU, JK DEBU, P PEYAUD, B TURLAY, R VALLAGE, B TI STUDY OF THE DECAY K(L)-]PI+/-PI(0)E+/-(NU)OVER-BAR-(NU) SO PHYSICAL REVIEW LETTERS LA English DT Article AB We have observed 729 +/- 15 K(L) --> pi+/-pi0e-/+ nuBAR(nu) decays in the data set collected in the 1987-1988 run of Fermilab experiment E731. We found the K(e4) branching ratio to be [5.16+/-0.20(stat) +/-0.22(syst)] x 10(-5). We also performed the first measurement of the form factors parametrizing the decay. Our branching ratio result agrees with a prediction using a vector-meson-exchange model. An interpretation of the data in terms of chiral perturbation theory implies a value L3 = (3.4+/-0.4) x 10(-3) in the O(p4) chiral Lagrangian. C1 UNIV CHICAGO,DEPT PHYS,CHICAGO,IL 60637. ELMHURST COLL,DEPT PHYS,ELMHURST,IL 60126. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. PRINCETON UNIV,PRINCETON,NJ 08544. CENS,DEPT PHYS PARTICULES ELEMENTAIRES,F-91191 GIF SUR YVETTE,FRANCE. RP MAKOFF, G (reprint author), UNIV CHICAGO,ENRICO FERMI INST,CHICAGO,IL 60637, USA. RI Briere, Roy/N-7819-2014 OI Briere, Roy/0000-0001-5229-1039 NR 19 TC 13 Z9 13 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 15 PY 1993 VL 70 IS 11 BP 1591 EP 1594 DI 10.1103/PhysRevLett.70.1591 PG 4 WC Physics, Multidisciplinary SC Physics GA KT366 UT WOS:A1993KT36600007 ER PT J AU SCHAFER, KJ YANG, B DIMAURO, LF KULANDER, KC AF SCHAFER, KJ YANG, B DIMAURO, LF KULANDER, KC TI ABOVE THRESHOLD IONIZATION BEYOND THE HIGH HARMONIC CUTOFF SO PHYSICAL REVIEW LETTERS LA English DT Article ID MULTIPHOTON IONIZATION; INTENSITY; ATOMS; LIGHT AB We present high sensitivity electron energy spectra for xenon in a strong 50 ps, 1.053 mum laser field. The above threshold ionization distribution is smoothly decreasing over the entire kinetic energy range (0-30 eV), with no abrupt changes in the slope. This is in direct contrast to the sharp cutoff observed in xenon optical harmonic generation spectra. Calculations using the single active electron approximation show excellent agreement with the observed electron distributions. These results directly address the unresolved relationship between the electron and photon emission from an atom in an intense field. C1 BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. RP SCHAFER, KJ (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 18 TC 748 Z9 756 U1 5 U2 48 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 15 PY 1993 VL 70 IS 11 BP 1599 EP 1602 DI 10.1103/PhysRevLett.70.1599 PG 4 WC Physics, Multidisciplinary SC Physics GA KT366 UT WOS:A1993KT36600009 ER PT J AU KELLOGG, GL AF KELLOGG, GL TI ELECTRIC-FIELD INHIBITION AND PROMOTION OF EXCHANGE DIFFUSION ON PT(001) SO PHYSICAL REVIEW LETTERS LA English DT Article ID SURFACE SELF-DIFFUSION; SINGLE ADATOMS; RECONSTRUCTION; AG(110); MECHANISM; ATOMS; IR AB Direct observations of a Pt adatom migrating on the Pt(001) plane in the presence of an externally applied electric field show that a positive field raises, and a negative field lowers, the activation barrier for the adatom-substrate-atom exchange process. At field strengths of 1.5 V/angstrom and above, inhibition of the exchange mechanism is sufficient to change the diffusion mode from exclusively exchange displacements to a mode that includes hops. The effect of the electric field is explained by an electron-transfer process which changes the bonding of the adatom to neighboring surface atoms. RP KELLOGG, GL (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 16 TC 45 Z9 45 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 15 PY 1993 VL 70 IS 11 BP 1631 EP 1634 DI 10.1103/PhysRevLett.70.1631 PG 4 WC Physics, Multidisciplinary SC Physics GA KT366 UT WOS:A1993KT36600017 ER PT J AU ARAGON, R GEHRING, PM SHAPIRO, SM AF ARAGON, R GEHRING, PM SHAPIRO, SM TI STOICHIOMETRY, PERCOLATION, AND VERWEY ORDERING IN MAGNETITE SO PHYSICAL REVIEW LETTERS LA English DT Article ID TRANSITION; FE3O4 AB Neutron scattering experiments on Fe3(1 - delta)O4 single crystals show that, for delta = 0, the well established additional Bragg Peaks occur at (h,0,l + 1/2), below T(V) = 122.5 K with abrupt disappearance of the diffuse planar scattering associated with 1D correlations along the cubic axis. For delta = 0.006, the superlattice peaks never become resolution limited, long-range order is not attained, and the diffuse scattering increases continuously with cooling. This composition exceeds the percolation limit beyond which the transition is inhibited by insufficient average charge per ordered unit cell. C1 BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP ARAGON, R (reprint author), UNIV DELAWARE,DEPT CHEM ENGN,NEWARK,DE 19716, USA. OI Gehring, Peter/0000-0002-9236-2046 NR 19 TC 53 Z9 54 U1 1 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 MAR 15 PY 1993 VL 70 IS 11 BP 1635 EP 1638 DI 10.1103/PhysRevLett.70.1635 PG 4 WC Physics, Multidisciplinary SC Physics GA KT366 UT WOS:A1993KT36600018 ER PT J AU WEI, SH ZHANG, SB ZUNGER, A AF WEI, SH ZHANG, SB ZUNGER, A TI OFF-CENTER ATOMIC DISPLACEMENTS IN ZINCBLENDE SEMICONDUCTOR SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRONIC-STRUCTURE; DX CENTERS; CU-HALIDES; ANOMALIES; SYSTEMS; DENSITY; DEFECT; MODEL; GAAS AB We have studied theoretically the conditions for the occurrence of spontaneous off-center atomic displacements in pure zinc-blende semiconductors. A pseudo Jahn-Teller coupling of a chemically active valence d band with an s-like conduction band is predicted to lead to such a metastability. All-electron density functional calculations confirm that this is the case in CuCl. The unusual experimental manifestations of this metastability are outlined. RP WEI, SH (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. RI Zunger, Alex/A-6733-2013; Krausnick, Jennifer/D-6291-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 23 TC 36 Z9 36 U1 3 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 15 PY 1993 VL 70 IS 11 BP 1639 EP 1642 DI 10.1103/PhysRevLett.70.1639 PG 4 WC Physics, Multidisciplinary SC Physics GA KT366 UT WOS:A1993KT36600019 ER PT J AU ZUO, JK WENDELKEN, JF AF ZUO, JK WENDELKEN, JF TI EXPERIMENTAL-STUDY OF SMOOTHING KINETICS ON A ROUGH-SURFACE SO PHYSICAL REVIEW LETTERS LA English DT Article ID CRYSTAL AB The smoothing kinetics of a rough surface have been studied using time-resolved high resolution low energy electron diffraction. By depositing approximately 100 monolayers of Cu on Cu(100) near room temperature, a rough surface results with an initial morphology of multilevel, roughly circular terraces separated by monatomic steps. Upon annealing at elevated temperatures, two growth regimes are distinguished for the average terrace width L (t) versus time t: The earlier one varies as t1/3, consistent with kinetics driven by the line tension of curved step edges, and the later one follows t1/5. Also, in the t1/3 growth regime, scaling is observed. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. NR 19 TC 29 Z9 29 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 15 PY 1993 VL 70 IS 11 BP 1662 EP 1665 DI 10.1103/PhysRevLett.70.1662 PG 4 WC Physics, Multidisciplinary SC Physics GA KT366 UT WOS:A1993KT36600025 ER PT J AU BALATSKY, AV ALTSHULER, BL AF BALATSKY, AV ALTSHULER, BL TI PERSISTENT SPIN AND MASS CURRENTS AND AHARONOV-CASHER EFFECT SO PHYSICAL REVIEW LETTERS LA English DT Article ID NEUTRAL PARTICLES; PHASE; RINGS AB Spin-orbit interaction produces persistent spin and mass currents in a ring via the Aharonov-Casher effect. An experiment in the He-3-A1 phase in which this effect leads to the excitation of mass and spin supercurrent is proposed. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. LD LANDAU THEORET PHYS INST,MOSCOW,RUSSIA. MIT,DEPT PHYS,CAMBRIDGE,MA 02139. RP BALATSKY, AV (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,T-11,LOS ALAMOS,NM 87545, USA. NR 14 TC 107 Z9 107 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 15 PY 1993 VL 70 IS 11 BP 1678 EP 1681 DI 10.1103/PhysRevLett.70.1678 PG 4 WC Physics, Multidisciplinary SC Physics GA KT366 UT WOS:A1993KT36600029 ER PT J AU GRAY, KE KIM, DH AF GRAY, KE KIM, DH TI INTERLAYER TUNNELING MODEL FOR THE C-AXIS RESISTIVITY IN HIGH-TEMPERATURE SUPERCONDUCTORS SO PHYSICAL REVIEW LETTERS LA English DT Article ID COPPER-OXIDE SUPERCONDUCTORS; MAGNETIC-FIELD; TRANSITION; STATES; TL2BA2CACU2OX AB The c-axis resistivity of Bi2Sr2CaCu2Ox single crystals shows a magnetic-field-dependent peak below the zero-field T(c). We find good agreement with the temperature and field dependence of the peak, by modeling the c-axis conduction as a series stack of Josephson tunnel junctions. For intermediate values of the Josephson coupling, we predict such a peak and verify it by measurements on discreet, thin-film Josephson junctions. The exaggerated effects in Bi2Sr2CaCu2Ox result from its unusually large energy gap and fluctuations. RP GRAY, KE (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. NR 32 TC 99 Z9 99 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 15 PY 1993 VL 70 IS 11 BP 1693 EP 1696 DI 10.1103/PhysRevLett.70.1693 PG 4 WC Physics, Multidisciplinary SC Physics GA KT366 UT WOS:A1993KT36600033 ER PT J AU FUCHS, HD ETCHEGOIN, P CARDONA, M ITOH, K HALLER, EE AF FUCHS, HD ETCHEGOIN, P CARDONA, M ITOH, K HALLER, EE TI VIBRATIONAL BAND MODES IN GERMANIUM - ISOTOPIC DISORDER-INDUCED RAMAN-SCATTERING SO PHYSICAL REVIEW LETTERS LA English DT Article ID NATURAL GE CRYSTALS; GE-70 AB We present Raman spectra of natural Ge, Ge-70, and (Ge0.5Ge0.5)-Ge-70-Ge-76 in the TO phonon region. The spectrum of the isotopically pure Ge-70 shows only the Raman-active phonon with k over arrow pointing right = 0 (GAMMA), as required by k over arrow pointing right conservation. The two isotopically disordered crystals, however, show spectra at the low energy side of the GAMMA phonon which correspond to isotopic disorder-induced scattering by TO phonons with k over arrow pointing right not-equal 0 (band modes). The line shape and the strength of the observed spectra agree with calculations based on the coherent potential approximation and an ansatz for the Raman polarizability. The novel (Ge0.5Ge0.5)-Ge-70-Ge-76 thus proves to be an ideal crystal to investigate mass disorder effects. C1 UNIV CALIF BERKELEY,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP FUCHS, HD (reprint author), MAX PLANCK INST FESTKORPERFORSCH,HEISENBERGSTR 1,W-7000 STUTTGART 80,GERMANY. RI Itoh, Kohei/C-5738-2014 NR 15 TC 42 Z9 42 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 MAR 15 PY 1993 VL 70 IS 11 BP 1715 EP 1718 DI 10.1103/PhysRevLett.70.1715 PG 4 WC Physics, Multidisciplinary SC Physics GA KT366 UT WOS:A1993KT36600039 ER PT J AU SWANSON, LS SHINAR, J AF SWANSON, LS SHINAR, J TI PHOTOLUMINESCENCE, ELECTROLUMINESCENCE, AND OPTICALLY DETECTED MAGNETIC-RESONANCE STUDY OF 2,5-DIALKOXY DERIVATIVES OF POLY(P-PHENYLENEACETYLENE) (PPA) AND PPA-BASED LIGHT-EMITTING-DIODES SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF ON SCIENCE AND TECHNOLOGY OF SYNTHETIC METALS ( ICSM 92 ) CY AUG 12-18, 1992 CL GOTEBORG, SWEDEN SP NESTE OY FINLAND, SWEDISH NAT SCI RES COUNCIL, SWEDISH NATL BOARD TECH DEV, SWEDISH INST, CITY GOTEBORG, LINKOPING UNIV, CHALMERS UNIV TECHNOL, ELSEVIER SEQUOIA, UNIAX, ABB CORPORATE RES DE POLY(P-PHENYLENEACETYLENE); ELECTROLUMINESCENCE; PHOTOLUMINESCENCE; ELECTROLUMINESCENCE-DETECTED MAGNETIC RESONANCE; CONDUCTIVITY-DETECTED MAGNETIC RESONANCE; POLARONS; BIPOLARONS; SINGLET EXCITONS; TRIPLET EXCITONS ID STRETCHED POLYTHIOPHENE FILMS; CONJUGATED POLYMERS; LUMINESCENCE; POLY(3-HEXYLTHIOPHENE); ANISOTROPIES; POLARONS; EXCITON AB The photoluminescence (PL) (i.e., optically)-detected magnetic resonance (ODMR) of the 2,5-dialkoxy derivatives of poly(p-phenyleneacetylene) (PPA) films and blends, and the electroluminescence (EL), conductivity (sigma)-, and EL-detected magnetic resonance of PPA-based LEDs is described. The weak vibronic structure of the intense PL peaking at approximately 1.95 eV and the broad tail extending beyond 800 nm are consistent with a relatively high degree of disorder. The ODMR spectra are similar to those of poly(3-alkylthiophenes) (P3ATs) and poly(p-phenylenevinylenes (PPVs), and attributable to magnetic resonance enhancement of singlet exciton generation by either polaron-polaron or triplet-triplet fusion. The broad, nearly symmetric half-field triplet ODMR is also consistent with considerably greater disorder than in P3ATs or PPVs. The EL spectrum of PPA-based diodes also reveals considerable disorder. They yield intense EL-quenching but sigma-enhancing resonances at g almost-equal-to 2.002, which are discussed in terms of polaron-to-bipolaron decay, and half-field EL- and sigma-detected resonances, assigned to triplet-triplet exciton fusion. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP SWANSON, LS (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 27 TC 55 Z9 55 U1 1 U2 5 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 MAR 15 PY 1993 VL 55 IS 1 BP 1 EP 6 DI 10.1016/0379-6779(93)90901-8 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA LG619 UT WOS:A1993LG61900002 ER PT J AU SWANSON, LS SHINAR, J BROWN, AR BRADLEY, DDC FRIEND, RH BURN, PL KRAFT, A HOLMES, AB AF SWANSON, LS SHINAR, J BROWN, AR BRADLEY, DDC FRIEND, RH BURN, PL KRAFT, A HOLMES, AB TI ELECTROLUMINESCENCE-DETECTED, CONDUCTIVITY-DETECTED, AND PHOTOCONDUCTIVITY-DETECTED MAGNETIC-RESONANCE STUDY OF POLY(P-PHENYLENEVINYLENE)-BASED LIGHT-EMITTING-DIODES SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF ON SCIENCE AND TECHNOLOGY OF SYNTHETIC METALS ( ICSM 92 ) CY AUG 12-18, 1992 CL GOTEBORG, SWEDEN SP NESTE OY FINLAND, SWEDISH NAT SCI RES COUNCIL, SWEDISH NATL BOARD TECH DEV, SWEDISH INST, CITY GOTEBORG, LINKOPING UNIV, CHALMERS UNIV TECHNOL, ELSEVIER SEQUOIA, UNIAX, ABB CORPORATE RES DE POLY(P-PHENYLENEVINYLENE); ELECTROLUMINESCENCE; PHOTOLUMINESCENCE; ELECTROLUMINESCENCE-DETECTED MAGNETIC RESONANCE; CONDUCTIVITY-DETECTED MAGNETIC RESONANCE; PHOTOCONDUCTIVITY-DETECTED MAGNETIC RESONANCE; POLARONS; BIPOLARONS; SINGLET EXCITONS; TRIPLET EXCITONS ID RECOMBINATION PROCESSES; CONJUGATED POLYMERS; SI-H; POLARONS; SPECTRA; SOLIDS AB The strong electroluminescence (EL)-detected magnetic resonance of poly(p-phenylenevinylene) (PPV)-based light emitting diodes is compared to the conductivity (sigma)-, photoconductivity (sigma(ph))- and photoluminescence (PL)-detected resonances. In contrast to the narrow PL-enhancing resonance assigned to polaron fusion into singlet excitons, strong EL- and sigma-quenching resonances are attributed to the spin-dependent polaron-to-bipolaron decay. While the half-field PL-detected resonance reveals only one triplet exciton resonance, believed to result from triplet-triplet fusion into singlets, the half-field EL- and sigma-detected resonances yield two distinct triplets. While both are sigma-enhancing, one is EL-quenching. The nature of the two triplet states is discussed. C1 UNIV CAMBRIDGE,CAVENDISH LAB,CAMBRIDGE CB3 0HE,ENGLAND. UNIV CAMBRIDGE,CHEM LAB,CAMBRIDGE CB2 1EW,ENGLAND. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. RP SWANSON, LS (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. RI Burn, Paul/F-5347-2010; Bradley, Donal/F-6068-2011 OI Bradley, Donal/0000-0001-8713-5060 NR 30 TC 14 Z9 14 U1 1 U2 3 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 MAR 15 PY 1993 VL 55 IS 1 BP 241 EP 248 DI 10.1016/0379-6779(93)90940-X PG 8 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA LG619 UT WOS:A1993LG61900041 ER PT J AU SWANSON, LS LANE, PA SHINAR, J PANG, Y BARTON, TJ AF SWANSON, LS LANE, PA SHINAR, J PANG, Y BARTON, TJ TI OPTICALLY DETECTED MAGNETIC-RESONANCE (ODMR) STUDY OF POLY(3-HEXYLTHIOPHENEACETYLENE (P3HTA) FILMS SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF ON SCIENCE AND TECHNOLOGY OF SYNTHETIC METALS ( ICSM 92 ) CY AUG 12-18, 1992 CL GOTEBORG, SWEDEN SP NESTE OY FINLAND, SWEDISH NAT SCI RES COUNCIL, SWEDISH NATL BOARD TECH DEV, SWEDISH INST, CITY GOTEBORG, LINKOPING UNIV, CHALMERS UNIV TECHNOL, ELSEVIER SEQUOIA, UNIAX, ABB CORPORATE RES DE POLYTHIOPHENEACETYLENE; PHOTOLUMINESCENCE; ODMR; POLARONS; SINGLET EXCITONS; TRIPLET EXCITONS ID STRETCHED POLYTHIOPHENE FILMS; RECOMBINATION PROCESSES; CONJUGATED POLYMERS; LUMINESCENCE; ANISOTROPIES; POLARONS; EXCITON; DIODES AB The photoluminescence (PL) and X-band ODMR of poly(3-hexylthiopheneacetylene) (P3HTA) films is described and discussed, As in poly(3-alkylthiophenes) (P3ATs), poly(p-phenylenevinylenes) (PPVs), poly(p-phenyleneacetylenes) (PPAs), and their derivatives, three PL-enhancing ODMR features are observed. The strongest is a narrow asymmetric (DELTAH-1/2 is similar to 14 G) line which is the sum of a broad Gaussian at g almost-equal-to 2.0032 +/- 0.0007 and a narrow Gaussian at g almost-equal-to 2.0022 +/- 0.0007. This asymmetry is slightly weaker than that found in P3ATs, but much stronger than in PPVs and PPAs. Since the resonance is attributed to polaron-polaron fusion into nongeminate singlet excitons, the lineshape thus indicates that P3HTA is more charge conjugation symmetric than P3ATs but less than PPVs and PPAs. The other two features are a broad full-field and a narrower half-field triplet powder pattern, attributed singlet exciton generation via triplet-triplet exciton fusion. However, while the half-field resonance of P3ATs, PPVs, and PPAs displays a single line, that of P3HTA is clearly resolved into two peaks. The nature of these observations is discussed in relation to disorder effects. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP SWANSON, LS (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 33 TC 10 Z9 10 U1 0 U2 3 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 MAR 15 PY 1993 VL 55 IS 1 BP 293 EP 298 DI 10.1016/0379-6779(93)90948-V PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA LG619 UT WOS:A1993LG61900049 ER PT J AU STEIN, PC EARL, WL RAY, A AF STEIN, PC EARL, WL RAY, A TI 2-DIMENSIONAL SOLID-STATE NMR-STUDIES OF POLY(ANILINE) SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF ON SCIENCE AND TECHNOLOGY OF SYNTHETIC METALS ( ICSM 92 ) CY AUG 12-18, 1992 CL GOTEBORG, SWEDEN SP NESTE OY FINLAND, SWEDISH NAT SCI RES COUNCIL, SWEDISH NATL BOARD TECH DEV, SWEDISH INST, CITY GOTEBORG, LINKOPING UNIV, CHALMERS UNIV TECHNOL, ELSEVIER SEQUOIA, UNIAX, ABB CORPORATE RES ID C-13 NMR; ORGANIC CONDUCTOR; CP-MAS; POLYANILINE AB We present a two-dimensional chemical exchange NMR experiment on an insulating sample of poly(aniline). This 2-D spectrum provides information about the local structure of the polymer chain. From the line shape, we can obtain the ratio of freely moving rings to rings ''frozen'' in place. The inhomogeneous broadening of the NMR lines indicate that the sample is structurally inhomogeneous. C1 LOS ALAMOS NATL LAB,DIV CHEM & LASER SCI,LOS ALAMOS,NM 87545. UNIV PENN,DEPT CHEM,PHILADELPHIA,PA 19104. RP STEIN, PC (reprint author), ODENSE UNIV,INST KEM,CAMPUSVEJ 55,DK-5230 ODENSE,DENMARK. RI Stein, Paul/M-9044-2015 OI Stein, Paul/0000-0002-7723-1419 NR 17 TC 4 Z9 4 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 MAR 15 PY 1993 VL 55 IS 1 BP 702 EP 707 DI 10.1016/0379-6779(93)91015-T PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA LG619 UT WOS:A1993LG61900116 ER PT J AU GREEN, PF BERGER, LL AF GREEN, PF BERGER, LL TI EFFECTS OF POLYIMIDE CHEMICAL-STRUCTURE AND ENVIRONMENT ON THE DIFFUSIVITY OF COPPER SO THIN SOLID FILMS LA English DT Article ID RAY PHOTOELECTRON-SPECTROSCOPY; TO-METAL ADHESION; CATHODIC DISBONDMENT; FILMS; INTERFACE; XPS AB Rutherford backscattering spectrometry was used to study the diffusion of copper into three fully imidized polyimides of differing chemical structure, electrophilicity and T(g). Samples were exposed to heat treatments in the different atmospheric environments of air, N2 and vacuum (10(-8) Torr). The coefficients D of the diffusion of copper oxide into the polyimide hosts was < 10(-18) cm2 s-1 when the samples were annealed under high vacuum conditions. In contrast, for samples annealed in a nitrogen atmosphere, the D value was orders of magnitude higher and its temperature dependence varied with T-1. Under these conditions, comparable diffusivities of copper oxide were observed in each of the polyimides. Moreover, when the polyimide samples were annealed in air, still higher values of D were found. For these samples, however, we were able to show conclusively that the degradation of the polyimide was considerable. C1 DUPONT CO,DEPT CENT RES & DEV,EXPT STN,WILMINGTON,DE 19898. RP GREEN, PF (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 23 TC 17 Z9 18 U1 0 U2 2 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 MAR 15 PY 1993 VL 224 IS 2 BP 209 EP 216 DI 10.1016/0040-6090(93)90434-Q PG 8 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA KR510 UT WOS:A1993KR51000013 ER PT J AU ANDERSON, CW LEESMILLER, SP LIN, D MERCER, WE SAKAGUCHI, K FISCELLA, M ULLRICH, S APPELLA, E AF ANDERSON, CW LEESMILLER, SP LIN, D MERCER, WE SAKAGUCHI, K FISCELLA, M ULLRICH, S APPELLA, E TI PHOSPHORYLATION OF THE P53 TUMOR SUPPRESSOR PROTEIN BY THE DNA-ACTIVATED PROTEIN-KINASE SO JOURNAL OF CELLULAR BIOCHEMISTRY LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973. THOMAS JEFFERSON UNIV,JEFFERSON CANC INST,PHILADELPHIA,PA 19107. NCI,CELL BIOL LAB,BETHESDA,MD 20892. NR 0 TC 0 Z9 0 U1 0 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0730-2312 J9 J CELL BIOCHEM JI J. Cell. Biochem. PD MAR 13 PY 1993 SU 17D BP 157 EP 157 PG 1 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA KV880 UT WOS:A1993KV88000543 ER PT J AU RUBIN, E AF RUBIN, E TI MODULATING ATHEROGENESIS BY MANIPULATING APOLIPOPROTEIN GENES IN MICE SO JOURNAL OF CELLULAR BIOCHEMISTRY LA English DT Meeting Abstract C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0730-2312 J9 J CELL BIOCHEM JI J. Cell. Biochem. PD MAR 13 PY 1993 SU 17D BP 173 EP 173 PG 1 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA KV880 UT WOS:A1993KV88000599 ER PT J AU WOON, DE AF WOON, DE TI ACCURATE MODELING OF INTERMOLECULAR FORCES - A SYSTEMATIC MOLLER-PLESSET STUDY OF THE ARGON DIMER USING CORRELATION CONSISTENT BASIS-SETS SO CHEMICAL PHYSICS LETTERS LA English DT Article ID PERTURBATION-THEORY AB The argon dimer potential energy curve has been investigated using Moller-Plesset perturbation theory through fourth-order (MP4) and the recently developed augmented correlation consistent basis sets for argon. The interaction energy has been determined using the supermolecule approach; trends in both uncorrected and counterpoise-corrected values are examined. The best corrected values attained for the well depth and equilibrium separation are, respectively, 0.42 mE(h) and 7.17 a0, which are in very good agreement with the empirical values of 0.45 mE(h) and 7.10 a0. Moreover, the regularity of the trends for the four basis sets used allows estimates of the complete basis set MP4 values, 0.45 mE(h) and 7.13 a0. RP WOON, DE (reprint author), PACIFIC NW LAB, MOLEC SCI RES CTR, BOX 999, RICHLAND, WA 99352 USA. NR 17 TC 101 Z9 101 U1 1 U2 8 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 MAR 12 PY 1993 VL 204 IS 1-2 BP 29 EP 35 DI 10.1016/0009-2614(93)85601-J PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR094 UT WOS:A1993KR09400005 ER PT J AU DAVIS, HF KIM, BS JOHNSTON, HS LEE, YT AF DAVIS, HF KIM, BS JOHNSTON, HS LEE, YT TI DISSOCIATION-ENERGY AND PHOTOCHEMISTRY OF NO3 SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID TEMPERATURE-DEPENDENCE; REACTIONS O+NO2->NO+O2; RATE CONSTANTS; PHOTODISSOCIATION; SPECTROSCOPY; NM; STRATOSPHERE; EQUILIBRIUM; KINETICS AB The photodissociation of NO3 was studied using the method of molecular beam photofragmentation translational spectroscopy. The existence of two photodissociation channels was confirmed under collision-free conditions. At excitation energies below D0(O-NO2) for internally cold NO3, we observe a large quantum yield (0.70 +/- 0.10 at 588 nm) for a concerted three-center rearrangement resulting in NO(2PI) + O2 (3SIGMA(g)-,1DELTA). The quantum yield for the NO + O2 channel decreased sharply at wavelengths shorter than 587 nm, falling to <0.01 at 583 nm, while the NO2 + O(3p) quantum yield increased to >0.99. On the basis of this wavelength dependence and the product translational energy distributions, we conclude that the wavelength threshold for NO3(0,0,0,0) --> NO2(0,0,0) + O(P-3(2)) is 587 +/- 3 nm, i.e. D0(O-NO2) = 48.69 +/- 0.25 kcal/mol. From the enthalpies of formation of O(P-3(2)) and NO2 (2A1), we calculate DELTAH(f)-degrees (NO3) = 18.87 +/- 0.33 kcal/mol at 0 K and DELTAH(f)-degrees (NO3) = 17.62 +/- 0.33 kcal/mol at 298 K. This is 2.23 kcal/mol higher than the most recent thermochemical value but is consistent with a value calculated indirectly using the most recent values for the electron affinity (EA) of NO3 and DELTAH(f)-degrees-(NO3-). From the wavelength dependence and translational energy distributions for NO3 --> NO + O2, the potential energy barrier for NO3(2A'2) --> NO(2PI) + O2 (2SIGMA(g)-) was found to be 47.3 +/- 0.8 kcal/mol. C1 LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RI kim, Bongsoo/E-4808-2012; Lee, Yuan-Tseh/F-7914-2012; Kim, Bongsoo/C-1545-2011 NR 57 TC 67 Z9 67 U1 2 U2 12 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 MAR 11 PY 1993 VL 97 IS 10 BP 2172 EP 2180 DI 10.1021/j100112a018 PG 9 WC Chemistry, Physical SC Chemistry GA KT155 UT WOS:A1993KT15500018 ER PT J AU KWEI, GH LAWSON, AC BILLINGE, SJL CHEONG, SW AF KWEI, GH LAWSON, AC BILLINGE, SJL CHEONG, SW TI STRUCTURES OF THE FERROELECTRIC PHASES OF BARIUM-TITANATE SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID NEUTRON POWDER DIFFRACTION; ATOMIC DEBYE TEMPERATURES; VIBRATIONAL PROPERTIES AB The structures of the three ferroelectric phases of BaTiO3 have been determined by Rietveld refinement using powder diffraction data collected at a spallation neutron source. The correlation between refined atomic displacements and thermal parameters, which has hampered previous structure determinations, has been partially alleviated by using data which extend over a wide range of d spacings. Data collected at a large number of sample temperatures provide information about the temperature dependence of the ferroelectric displacements and changes in the oxygen octahedra which surround the Ti ions. The temperature dependence of the thermal parameters gives atomic Debye-Waller temperatures that are remarkably similar to those for the cations in the high-T(c) superconductors. Our results are insensitive to predictions of a soft-mode displacive model; however, values of the anisotropic thermal parameters do not support the order-disorder model suggested by Comes et al. Powder extinction and profile coefficients from the structural refinements show pronounced minima and maxima, respectively, near the phase transitions and provide information about the temperature dependence of the mosaic structure and the strain in the different phases. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. RP KWEI, GH (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 47 TC 319 Z9 319 U1 19 U2 144 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 MAR 11 PY 1993 VL 97 IS 10 BP 2368 EP 2377 DI 10.1021/j100112a043 PG 10 WC Chemistry, Physical SC Chemistry GA KT155 UT WOS:A1993KT15500043 ER PT J AU ECKERT, J KUBAS, GJ AF ECKERT, J KUBAS, GJ TI BARRIER TO ROTATION OF THE DIHYDROGEN LIGAND IN METAL-COMPLEXES SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID MOLECULAR-HYDROGEN COMPLEXES; INTRAMOLECULAR REARRANGEMENTS; NEUTRON-SCATTERING; NEIGHBOR LIGANDS; XENON SOLUTION; SOLID-STATE; H-2; FE(H)2(ETA-2-H2)(PETPH2)3; ETA-2-H-2; DYNAMICS AB The fact that certain metal complexes will bind hydrogen in molecular form has provided an opportunity to examine in the solid state the simplest hindered molecular rotation problem, namely, that of a dumbbell molecule in a double-minimum potential with one rotational degree of freedom. The barrier to rotation of this novel ligand is derived from inelastic neutron scattering measurements of its rotational transitions and interpreted in terms of the various types of interactions that give rise to it. These include the direct electronic interaction between dihydrogen and the metal, electronic effects (via the metal) of the other ligands on the metal, and steric effects. The remarkable result of these studies is that the barrier to rotation of dihydrogen serves as a very sensitive probe of some of the electronic interactions between the metal and its ligands. It also serves as the principal quantiative benchmark for electronic calculations aimed at arriving at an understanding of dihydrogen metal binding. In this paper we combine several new barrier height results with those from our previous work to discuss systematics of the variation of barrier height with the type of metal center, the nature of the coligands and counterions as well as their implications for metal-dihydrogen binding, and H-H bond activation. C1 LOS ALAMOS NATL LAB,INC1,MSC-346,LOS ALAMOS,NM 87545. RP ECKERT, J (reprint author), LOS ALAMOS NATL LAB,LANSCE,MSH805,LOS ALAMOS,NM 87545, USA. NR 38 TC 79 Z9 79 U1 0 U2 5 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 MAR 11 PY 1993 VL 97 IS 10 BP 2378 EP 2384 DI 10.1021/j100112a044 PG 7 WC Chemistry, Physical SC Chemistry GA KT155 UT WOS:A1993KT15500044 ER PT J AU GROTHUES, D CANTOR, CR SMITH, CL AF GROTHUES, D CANTOR, CR SMITH, CL TI PCR AMPLIFICATION OF MEGABASE DNA WITH TAGGED RANDOM PRIMERS (T-PCR) SO NUCLEIC ACIDS RESEARCH LA English DT Article ID ENZYMATIC AMPLIFICATION; SEQUENCES; GENOME C1 LAWRENCE BERKELEY LAB,DIV STRUCT BIOL,BERKELEY,CA 94720. RP GROTHUES, D (reprint author), UNIV CALIF BERKELEY,DEPT MOLEC & CELL BIOL,BERKELEY,CA 94720, USA. OI Smith, Cassandra/0000-0002-0346-8907 NR 10 TC 59 Z9 63 U1 1 U2 1 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 MAR 11 PY 1993 VL 21 IS 5 BP 1321 EP 1322 DI 10.1093/nar/21.5.1321 PG 2 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA KT343 UT WOS:A1993KT34300043 PM 8464718 ER PT J AU DORSO, C RANDRUP, J AF DORSO, C RANDRUP, J TI EARLY RECOGNITION OF CLUSTERS IN MOLECULAR-DYNAMICS SO PHYSICS LETTERS B LA English DT Article ID CLASSICAL SIMULATION AB We propose a novel method for recognizing bound clusters in molecular dynamics simulations of nuclear collisions. Demanding that each particle in a given cluster is bound with respect to that cluster, we employ a Metropolis procedure (akin to simulated annealing) to maximize the cluster binding. Remarkably, the cluster structure can be identified approximately well before spatial separation occurs. C1 LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. NR 6 TC 114 Z9 117 U1 0 U2 2 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 MAR 11 PY 1993 VL 301 IS 4 BP 328 EP 333 DI 10.1016/0370-2693(93)91158-J PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KQ112 UT WOS:A1993KQ11200002 ER PT J AU FIELDS, BD SCHRAMM, DN TRURAN, JW AF FIELDS, BD SCHRAMM, DN TRURAN, JW TI BERYLLIUM AND BORON CONSTRAINTS ON AN EARLY GALACTIC BRIGHT PHASE SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMIC RAYS; ELEMENTARY PARTICLES; NUCLEAR REACTIONS, NUCLEOSYNTHESIS, ABUNDANCES; STARS, EVOLUTION ID COSMIC-RAY SPECTRUM; STARS; ABUNDANCES; NUCLEOSYNTHESIS; LITHIUM; DWARFS; RATIO; MODEL; LI AB The recent observations of Be and B in metal-deficient halo dwarfs are used to constrain a '' bright phase '' of enhanced cosmic-ray flux in the early Galaxy. Assuming that this Be and B arises from cosmic-ray spallation in the early Galaxy, limits are placed on the intensity of the early (Population II) cosmic-ray flux relative to the present (Population I) flux. A simple estimate of bounds on the flux ratio is 1 less than or similar PHI(Pop II)/PHI(Pop I) less than or similar 40. This upper bound would restrict galaxies like our own from producing neutrino fluxes that would be detectable in any currently proposed detectors. It is found that the relative enhancement of the early flux varies inversely with the relative time of enhancement. It is noted that associated gamma-ray production via pp --> pi0pp may be a significant contribution to the gamma-ray background above 100 MeV. C1 NASA,FERMILAB ASTROPHYS GRP,FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. NR 51 TC 7 Z9 7 U1 1 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 1993 VL 405 IS 2 BP 559 EP 566 DI 10.1086/172387 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KP612 UT WOS:A1993KP61200016 ER PT J AU KIGUCHI, K HENNINGCHUBB, C HUBERMAN, E AF KIGUCHI, K HENNINGCHUBB, C HUBERMAN, E TI GLYCOSPHINGOLIPID PATTERNS IN HUMAN PROMYELOCYTIC HL-60 LEUKEMIA-CELLS SUSCEPTIBLE OR RESISTANT TO DIFFERENTIATION INDUCTION BY PHORBOL 12-MYRISTATE 13-ACETATE SO BIOCHIMICA ET BIOPHYSICA ACTA LA English DT Article DE GLYCOSPHINGOLIPID; GANGLIOSIDE; MONOCYTE MACROPHAGE DIFFERENTIATION; UDP-GLUCOSE, CERAMIDE GLUCOSYLTRANSFERASE; UDP-GALACTOSE, GLUCOSYLCERAMIDE BETA-GALACTOSYLTRANSFERASE; CMP-N-ACETYLNEURAMINIC ACID, LACTOSYLCERAMIDE SIALYLTRANSFERASE ID PROTEIN KINASE-C; TUMOR-PROMOTING AGENTS; MONOCLONAL-ANTIBODY; LINE HL-60; MONOCYTIC DIFFERENTIATION; HUMAN-LEUKOCYTES; GLYCOLIPIDS; GANGLIOSIDES; ANTIGEN; GRANULOCYTES AB The patterns of glycosphingolipids (GSLs) were analyzed in an HL-60 cell variant, HL-205, which is susceptible to phorbol 12-myristate 13-acetate (PMA)-induced monocyte/macrophage differentiation, and in an HL-60 cell variant, HL-525, which is resistant to such differentiation. The amounts and types of the GSLs were similar in both the HL-205 and HL-525 cells and they resemble those of granulocytes. Treatment with 3 nM PMA caused the susceptible HL-205 cells (but not the resistant cells) to acquire a new GSL pattern which resembles that of monocytes. This new pattern was characterized by increases in the level of a neutral GSL, Gb3Cer, from trace levels to 0.05 mg/10(9) cells and of an acidic GSL, G(M3) ganglioside, from 0.03 to 0.33 mg/10(9) cells. The increases in the level of this ganglioside were found to be due to an increase in CMP-N-acetylneuraminic acid: lactosylceramide sialyltransferase activity. These results indicate an association between PMA-induced terminal differentiation along the monocyte/macrophage cell lineage and PMA-evoked increases in specific GSLs, G(M3) in particular, which is due to a rise in the activity of its synthetic enzyme. C1 ARGONNE NATL LAB,DIV BIOL & MED RES,9700 S CASS AVE,ARGONNE,IL 60439. NR 46 TC 7 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0006-3002 J9 BIOCHIM BIOPHYS ACTA PD MAR 10 PY 1993 VL 1176 IS 1-2 BP 27 EP 36 DI 10.1016/0167-4889(93)90173-M PG 10 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA KR266 UT WOS:A1993KR26600005 PM 8452876 ER PT J AU WALTER, WR BRUNE, JN AF WALTER, WR BRUNE, JN TI SPECTRA OF SEISMIC RADIATION FROM A TENSILE CRACK SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID TECTONIC STRESS; SOURCE MODELS; EARTHQUAKE; CALIFORNIA; AFTERSHOCK; INTRUSION; WAVES; FAULT; ANZA AB A model for the average far-field P and S wave amplitude spectra from a circular crack failing in tension is presented. The model explicitly avoids specifying the details of the rupture process; instead, the spectral amplitude is determined by applying physically realistic constraints to an idealized spectral shape for each wave type. The idealized spectral form is given by OMEGA(o)/(1 + (omega(omega(c))2)psi/2, where omega(c) is a parameter representing the corner frequency, OMEGA(o) determines the overall scaling of the spectra, and psi determines the falloff at high frequencies. For fixed psi, the complete specification of the body wave spectra, P and S waves, requires the determination of four unknowns: OMEGA(o)P, OMEGA(o)S, omega(c)P, omega(c)P, and omega(c)S. The P and S spectral models are constrained by fixing the low-frequency level of each to be equivalent to a point source. They arc further constrained by equating the total radiated energy with the available elastic energy through a seismic efficiency parameter eta. A final constraint between the comer frequencies of the P and S spectra is needed to determine the four free parameters. For the type of model considered here: an equidimensional fault with greatest displacement in the center, we expect the P to S comer frequency ratio to range between 1 and 1.73 depending on the details of the rupture. For psi = 2, this model gives an average S/P spectral amplitude ratio of about 2.1 at very low frequencies and between 2.1 and 0.7 at very high frequencies, depending on the P to S comer frequency ratio. Applying the same criteria to a circular shear crack gives an average S/P spectral amplitude of about 7.1 at very low frequencies and between 7.1 and 2.4 at very high frequencies, again depending on the P to S corner frequency ratio. The tensional crack thus has lower average S/P spectral amplitudes than the shear crack, and such low S/P spectral amplitudes may be an identifying characteristic of tensile or tensile equivalent rupture. Using the shear and tensional models, we construct composite spectra that have significantly smaller S/P spectral amplitude ratios than the shear cracks alone, even when the tensional events radiate just a fraction of the total seismic energy. The tensile crack average spectral model may be useful as a first approximation for modeling seismic sources with a volumetric component in them, such as slip on a nonplanar fault, or magma injection. C1 UNIV NEVADA,MACKAY SCH MINES,SEISMOL LAB,RENO,NV 89503. RP WALTER, WR (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT EARTH SCI,POB 808,LIVERMORE,CA 94550, USA. RI Walter, William/C-2351-2013 OI Walter, William/0000-0002-0331-0616 NR 42 TC 28 Z9 28 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAR 10 PY 1993 VL 98 IS B3 BP 4449 EP 4459 DI 10.1029/92JB02414 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KQ873 UT WOS:A1993KQ87300026 ER PT J AU SCOTT, SL ESPENSON, JH ZHU, ZL AF SCOTT, SL ESPENSON, JH ZHU, ZL TI REACTIVITY OF 17-ELECTRON ORGANOMETALLIC TUNGSTEN AND MOLYBDENUM RADICALS - A LASER FLASH-PHOTOLYSIS STUDY SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ATOM TRANSFER-REACTIONS; METAL BONDED COMPLEXES; MANGANESE CARBONYL RADICALS; ELECTRON-SPIN RESONANCE; OXIDATIVE-ADDITION; ORGANIC HALIDES; SUBSTITUTION-REACTIONS; DISSOCIATION ENERGIES; AQUEOUS-SOLUTION; RATE CONSTANTS AB Visible (460-490 nm) laser flash photolysis of [CpW(CO)3]2 or [CpMo(CO)3]2 induces homolysis of the metal-metal bond with formation of 17-electron radicals, CpM(CO)3. Radical dimerization results in quantitative recovery of the parent dimer and can be followed by the time-resolved increase in dimer absorbance. The reaction follows clean second-order kinetics, -d[CpM(CO)3]/dt = 2k(c)[CpM(CO)3]2; k(c)(W) = 6.2 x 10(9) and k(c)(Mo) = 3.9 x 10(9) L mol-1 s-1 in CH3CN at 23-degrees-C. The CpM(CO)3 radicals react with organic and inorganic halides and pseudohalides by an atom-transfer mechanism. In the presence of a large excess of the halide-containing substrate, the rate of loss of the radical, -d[CpM(CO)3]/dt, proceeds according to a mixed first- and second-order rate law. The pseudo-first-order rate constants for reactions with organic halides vary linearly with the concentration of the organic halide; bimolecular rate constants for CpW(CO)3 range from 3.9 x 10(2) L mol-1 s-1 with CH2Br2 to 1.34 X 10(9) L mol-1 s-1 for CBr4. The reactivity trends (RI > RBr > RCl) and (benzyl > allyl > 3-degrees > 2-degrees > 1-degrees > CH3) are observed. The 7 orders of magnitude variation in bimolecular rate constants is attributed to a highly selective atom abstraction process. The range of rate constants for atom abstraction from halo- and pseudohalopentaamminecobalt(III) and halobis(dimethylglyoximato)cobalt(III) complexes is smaller (2 orders of magnitude, from 1.6 x 10(7) L mol-1 s-1 for NCCo(NH3)52+ to >2 X 10(9) L mol-1 s-1 for BrCo(dmgH)2py), because of the upper limit imposed by diffusion. Transfer of the halogen atom from both organic and metal substrates to CpW(CO)3 was confirmed by the IR spectrum of the organometallic product, CpW(CO)3X (X = Cl, Br, or I). Dioxygen traps CpW(CO)3 with a rate constant k = 3.3 x 10(9) L mol-1 s-1. Light-initiated chain reactions were observed at high concentrations of RX, XCoL5n+, or O2. Hydroperoxides react with CpW(CO)3 by a radical mechanism. The reaction observed between CpW(CO)3 and (n-Bu)3SnH is not consistent with either outer-sphere electron transfer or a hydrogen atom abstraction mechanism; oxidative addition to the 17-electron radical is believed to occur in this case. The dimer [(C5H4COOCH3)W(CO)3]2 shows photoreactivity in organic solvents which is very similar to that of [CpW(CO)3]2. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 97 TC 55 Z9 55 U1 1 U2 6 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 MAR 10 PY 1993 VL 115 IS 5 BP 1789 EP 1797 DI 10.1021/ja00058a025 PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA KR825 UT WOS:A1993KR82500025 ER PT J AU MAIA, MP COOPER, PS STUTTE, L SOLYANIK, V FILIMONOV, I NEMITKIN, A AF MAIA, MP COOPER, PS STUTTE, L SOLYANIK, V FILIMONOV, I NEMITKIN, A TI A PHOTOTUBE RICH DETECTOR SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID CHERENKOV AB The results from a prototype for a fast RICH detector using phototubes are presented, testing three different types of tubes in the photocathode, In a 400 GeV/c pi- beam, the number of photons detected was 11.8 per ring and the ring radius resolution obtained was 1.13%. The figure of merit, N0, for the entire photocathode was measured to be 93/cm. Particle identification as a function of beam momentum was studied, as well as multiparticle event recognition. C1 CONSELHO NACL PESQUISAS,BR-22290 RIO JANEIRO,RJ,BRAZIL. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. INST HIGH ENERGY PHYS,SERPUKHOV,RUSSIA. MOSCOW MV LOMONOSOV STATE UNIV,MOSCOW,RUSSIA. NR 7 TC 15 Z9 15 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 MAR 10 PY 1993 VL 326 IS 3 BP 496 EP 507 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KQ930 UT WOS:A1993KQ93000011 ER PT J AU ROBERSON, NR BOWMAN, CD BOWMAN, JD DELHEIJ, PPJ FRANKLE, CM GOULD, CR HAASE, DG KNUDSON, JN MITCHELL, GE MORTENSEN, RN PENTTILA, SI POSTMA, H SEESTROM, SJ SZYMANSKI, JJ WENDER, SA YOO, SH YUAN, VW ZHU, X AF ROBERSON, NR BOWMAN, CD BOWMAN, JD DELHEIJ, PPJ FRANKLE, CM GOULD, CR HAASE, DG KNUDSON, JN MITCHELL, GE MORTENSEN, RN PENTTILA, SI POSTMA, H SEESTROM, SJ SZYMANSKI, JJ WENDER, SA YOO, SH YUAN, VW ZHU, X TI AN APPARATUS AND TECHNIQUES OF TESTS FOR FUNDAMENTAL SYMMETRIES IN COMPOUND-NUCLEUS SCATTERING WITH EPITHERMAL POLARIZED NEUTRON BEAMS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID PARITY NONCONSERVATION; RESONANCES; LA-139; ENHANCEMENT; VIOLATION AB The epithermal polarized-neutron beam facility used for tests of fundamental symmetries is described. The initial unpolarized beam is obtained from the spallation source at the Los Alamos Neutron Scattering Center. Characteristics of the polarized and unpolarized beams are described, as well as design and performance of a fast-spin reversal system, neutron flux monitor and target cooler. Experimental results for polarized-neutron transmission experiments are given to illustrate the overall quality of the system. C1 TRIANGLE UNIV NUCL LAB,DURHAM,NC 27708. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. TRIUMF,VANCOUVER V6T 2A3,BC,CANADA. N CAROLINA STATE UNIV,RALEIGH,NC 27695. UNIV TECHNOL DELFT,2628 CJ DELFT,NETHERLANDS. RP ROBERSON, NR (reprint author), DUKE UNIV,DURHAM,NC 27708, USA. RI Gould, Christopher/M-7676-2013 NR 36 TC 36 Z9 36 U1 0 U2 2 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 MAR 10 PY 1993 VL 326 IS 3 BP 549 EP 565 DI 10.1016/0168-9002(93)90858-F PG 17 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KQ930 UT WOS:A1993KQ93000018 ER PT J AU EBERHARD, P LYNCH, G LAMBERT, D AF EBERHARD, P LYNCH, G LAMBERT, D TI FITS OF MONTE-CARLO DISTRIBUTIONS TO DATA SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB This paper is devoted to likelihood fits to binned data in which the contents of the bins are simple counts of independent events. It addresses the case where the distribution to be fitted is the sum of distributions of events due to different physical processes, and the prediction of each one of these processes is given by a distribution of events generated by a Monte Carlo program, binned like the real events. This paper suggests a method to analyze the properties of these individual processes. It also gives an example of its use in the analysis of jet production in e+e- interactions. RP EBERHARD, P (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 4 TC 3 Z9 3 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 MAR 10 PY 1993 VL 326 IS 3 BP 574 EP 580 DI 10.1016/0168-9002(93)90861-B PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KQ930 UT WOS:A1993KQ93000021 ER PT J AU ANDERSON, DF KWAN, S PESKOV, V AF ANDERSON, DF KWAN, S PESKOV, V TI CSI PHOTOCATHODE QE AND A SIMPLE PRODUCTION TECHNIQUE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Letter AB The importance on quantum efficiency of a CsI photocathode of the starting material used, the deposition procedure, and electric field on the photocathode is discussed. A simple, non vacuum-deposition technique for making CsI photocathodes is also presented. RP ANDERSON, DF (reprint author), FERMILAB NATL ACCELERATOR LAB,PARTICLE DETECTOR GRP,BATAVIA,IL 60510, USA. NR 6 TC 35 Z9 35 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 MAR 10 PY 1993 VL 326 IS 3 BP 611 EP 612 DI 10.1016/0168-9002(93)90866-G PG 2 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KQ930 UT WOS:A1993KQ93000026 ER PT J AU NATESAN, K AF NATESAN, K TI APPLICATIONS OF COATINGS IN COAL-FIRED ENERGY-SYSTEMS SO SURFACE & COATINGS TECHNOLOGY LA English DT Review ID THERMAL BARRIER COATINGS; BASE ALLOYS; PERFORMANCE AB Corrosion and erosion of metallic structural materials at elevated temperatures in complex multicomponent gas environments that include particulates are potential problems in many fossil energy systems, especially those using coal as a feedstock. The use of appropriate corrosion-resistant coatings on metallic components offers an avenue to minimize material degradation and to extend component life. The purpose of this paper is to review the current status of coating performance in environments typical of pulverized-coal-fired boilers, coal gasification, fluidized-bed combustion, and gas turbines. The complexity of environments in different systems and the coating requirements for acceptable performance are discussed. Examples illustrate the morphology and corrosion-erosion performance of coating-structural alloy combinations exposed in some of these systems. In addition, future research and development needs are discussed for coating applications in several coal-fired systems. RP NATESAN, K (reprint author), ARGONNE NATL LAB,DIV MAT & COMPONENTS TECHNOL,ARGONNE,IL 60439, USA. NR 27 TC 14 Z9 14 U1 0 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD MAR 10 PY 1993 VL 56 IS 3 BP 185 EP 197 DI 10.1016/0257-8972(93)90251-I PG 13 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA KR513 UT WOS:A1993KR51300001 ER PT J AU RAMAN, NK WARD, TL BRINKER, CJ SEHGAL, R SMITH, DM DUAN, Z HAMPDENSMITH, M BAILEY, JK HEADLEY, TJ AF RAMAN, NK WARD, TL BRINKER, CJ SEHGAL, R SMITH, DM DUAN, Z HAMPDENSMITH, M BAILEY, JK HEADLEY, TJ TI CATALYST DISPERSION ON SUPPORTED ULTRAMICROPOROUS INORGANIC MEMBRANES USING DERIVATIZED SILYLATION AGENTS SO APPLIED CATALYSIS A-GENERAL LA English DT Article DE CATALYST DISPERSION; COMPOSITES; MEMBRANES; MEMBRANE REACTOR; RHODIUM; SILYLATION ID CATALYTICALLY ACTIVE MEMBRANES; ALUMINA MEMBRANES; DEHYDROGENATION; REACTOR; GAS AB Two approaches were utilized to disperse rhodium metal particles onto the ultramicroporous silica separation layer of a composite inorganic membrane prepared by modification of a commercial alumina support. In one approach, the silica membrane surface was first amine-derivatized using the silylation agent H2N(CH2)2NH(CH2)3Si(OCH3)3, followed by reaction with the metal-organic compound [(1,5-COD) RhCl]2. This approach led to uniformly dispersed ca. 6 nm rhodium particles located only on the surface of the membrane (as revealed by cross-sectional transmission electron microscopy) after a hydrogen reduction at 200-degrees-C. The size of the [(1,5-COD) RhCl]2 molecule combined with a reduction of the pore size due to silylation apparently prevented significant penetration into the membrane separation layer. Modest reductions (ca. 50%) in helium and nitrogen permeability resulted from this treatment. An alternative procedure involved wet impregnation of the membrane with a (Rh (acac)3)/THF solution, followed by air calcination and hydrogen reduction. This approach produced a much lower coverage of ca. 4 nm rhodium particles. Helium and nitrogen permeability measurements indicated that considerable pore blockage existed after the calcination step, and that the reduction step led to defect or crack formation in the SiO2 membrane layer as evidenced by a sizeable increase in permeability. It was proposed that the silylation approach led to the [(1,5-COD) RhCl]2 precursor being located primarily on the surface with little pore penetration, while the Rh(acac)3 was able to penetrate the pores to a greater extent, leading to damage of the membrane layer during decomposition of the ligands. The silylation approach appears to be a general strategy to control the size, surface coverage, and location of catalyst in catalytic membrane design. C1 SANDIA NATL LABS,DEPT CERAM SYNTH & INORGAN CHEM 1846,ALBUQUERQUE,NM 87185. UNIV NEW MEXICO,NSF,CTR MICROENGINEERED CERAM,ALBUQUERQUE,NM 87131. NR 27 TC 9 Z9 9 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-860X J9 APPL CATAL A-GEN JI Appl. Catal. A-Gen. PD MAR 8 PY 1993 VL 96 IS 1 BP 65 EP 82 DI 10.1016/0926-860X(93)80007-D PG 18 WC Chemistry, Physical; Environmental Sciences SC Chemistry; Environmental Sciences & Ecology GA KT589 UT WOS:A1993KT58900007 ER PT J AU FOLLSTAEDT, DM AF FOLLSTAEDT, DM TI RELATIVE FREE-ENERGIES OF SI SURFACES SO APPLIED PHYSICS LETTERS LA English DT Article ID TRANSMISSION AB Cavities are formed by ion implanting (001) Si with He and annealing at 800-degrees-C to enlarge and to remove the He. Subsequent annealing at 600-degrees-C results in cavities with well-defined facets as seen in [110] cross section with transmission electron microscopy. The most frequently observed facets are {111} planes. A rounded surface is seen about the [001] direction of all cavities, and (110BAR) facets are seen less frequently. The cavities allow the equilibrium crystal shape of Si to be examined and the relative free energies of the observed planes to be measured. The surface free energies of {001} and {110} planes are found to be 1.09+/-0.07 and 1.07+/-0.03 times that of {111} planes, respectively. RP FOLLSTAEDT, DM (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 22 TC 77 Z9 78 U1 1 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 MAR 8 PY 1993 VL 62 IS 10 BP 1116 EP 1118 DI 10.1063/1.108760 PG 3 WC Physics, Applied SC Physics GA KQ316 UT WOS:A1993KQ31600029 ER PT J AU XIAO, Y HEBEN, MJ MCCULLOUGH, JM TSUO, YS PANKOVE, JI DEB, SK AF XIAO, Y HEBEN, MJ MCCULLOUGH, JM TSUO, YS PANKOVE, JI DEB, SK TI ENHANCEMENT AND STABILIZATION OF POROUS SILICON PHOTOLUMINESCENCE BY OXYGEN INCORPORATION WITH A REMOTE-PLASMA TREATMENT SO APPLIED PHYSICS LETTERS LA English DT Article AB We report a treatment that enhances and stabilizes the photoluminescence (PL) from porous Si films. Films prepared by anodization in a 50% HF/ethanol solution were annealed at 450-degrees-C in vacuum, exposed to air, and then exposed to a remote-hydrogen plasma. Infrared absorption spectroscopy revealed that the concentration of oxygen, rather than hydrogen, was increased by the processing steps, and that silicon dihydride species had been eliminated from the surface. The PL from a treated film was initially approximately 30 times more intense than from the as-etched films. The PL intensity increased with illumination time in air until a steady-state intensity was reached. C1 UNIV COLORADO,DEPT ELECT & COMP ENGN,BOULDER,CO 80309. COLORADO SCH MINES,DEPT PHYS,GOLDEN,CO 80401. RP XIAO, Y (reprint author), NATL RENEWABLE ENERGY LAB,DIV BASIC SCI,GOLDEN,CO 80401, USA. NR 15 TC 70 Z9 80 U1 1 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 MAR 8 PY 1993 VL 62 IS 10 BP 1152 EP 1154 DI 10.1063/1.108772 PG 3 WC Physics, Applied SC Physics GA KQ316 UT WOS:A1993KQ31600041 ER PT J AU BLOCKI, J BRUT, F SWIATECKI, WJ AF BLOCKI, J BRUT, F SWIATECKI, WJ TI A NUMERICAL VERIFICATION OF THE PREDICTION OF AN EXPONENTIAL VELOCITY SPECTRUM FOR A GAS OF PARTICLES IN A TIME-DEPENDENT POTENTIAL WELL SO NUCLEAR PHYSICS A LA English DT Article AB Using computer simulations we demonstrate that, as predicted by Jarzynski and Swiatecki, the velocity distribution f(v) for a gas of independent particles bouncing around chaotically in several types of deforming containers tends to an exponential function of nu. The generalized one-body dissipation formula for the heating up of such a gas, also derived by Jarzynski and Swiatecki, is shown to give a good overall account of the numerical results, although small deviations are apparent. C1 UNIV GRENOBLE 1,INST SCI NUCL,IN2P3,CNRS,53 AV MARTYRS,F-38026 ST MARTIN DHERES,FRANCE. INST NUCL STUDIES,PL-05400 OTWOCK,POLAND. LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. NR 9 TC 14 Z9 14 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 MAR 8 PY 1993 VL 554 IS 1 BP 107 EP 117 DI 10.1016/0375-9474(93)90360-A PG 11 WC Physics, Nuclear SC Physics GA KU737 UT WOS:A1993KU73700006 ER PT J AU MORELLI, A AF MORELLI, A TI HIGHER-TWIST EFFECT ON PION STRUCTURE FUNCTIONS FROM LATTICE QCD SO NUCLEAR PHYSICS B LA English DT Article ID ELECTRON-DEUTERON SCATTERING; MUON-PAIR PRODUCTION; WILSON FERMIONS; 4-FERMION OPERATORS; POWER CORRECTIONS; CURRENT-ALGEBRA; QUARK-MODEL; CONSTANTS; BARYONS; ELECTROPRODUCTION AB The second Nachtmann moment of the I-spin = 2 linear combination of pion structure function, which is a pure higher-twist effect, is calculated in lattice QCD at beta = 6.0 with Wilson fermions in the quenched approximation. The values of B-factors of the spin-2 four-fermions operators involved in the calculation span between 0.5 and 2.0, so that the higher-twist scale for this particular moment turns out to be of the order of the pion decay constant. The results of lattice calculation are compared with the ones from the bag model, the potential quark models and the 1/N approximation. C1 INFN,I-00185 ROME,ITALY. RP MORELLI, A (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 52 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD MAR 8 PY 1993 VL 392 IS 2 BP 518 EP 548 DI 10.1016/0550-3213(93)90683-G PG 31 WC Physics, Particles & Fields SC Physics GA KU684 UT WOS:A1993KU68400010 ER PT J AU ATWOOD, D EILAM, G SONI, A MENDEL, RR MIGNERON, R AF ATWOOD, D EILAM, G SONI, A MENDEL, RR MIGNERON, R TI CP VIOLATION IN SEMILEPTONIC TOP QUARK DECAYS IN THE WEINBERG MODEL SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRIC-DIPOLE MOMENT; NONCONSERVATION AB We show that the charged Higgs sector in Weinberg's model for CP violation can cause a large CP violation effect in t --> btaunu(tau). The asymmetry in the partial rate is dominated by contributions such as Z(and gamma)-H+ box diagrams interfering with a (near-resonance) W tree diagram. But far more significant are the asymmetries in the partially integrated rates and in the energy between the tau+ and the tau-. These stem from (near-resonance) W-tree-H+-tree interference. C1 TECHNION ISRAEL INST TECHNOL,DEPT PHYS,IL-32000 HAIFA,ISRAEL. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. UNIV WESTERN ONTARIO,DEPT APPL MATH,LONDON N6A 5B9,ONTARIO,CANADA. NR 33 TC 37 Z9 37 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 8 PY 1993 VL 70 IS 10 BP 1364 EP 1367 DI 10.1103/PhysRevLett.70.1364 PG 4 WC Physics, Multidisciplinary SC Physics GA KQ414 UT WOS:A1993KQ41400003 ER PT J AU GRAUDENZ, D SPIRA, M ZERWAS, PM AF GRAUDENZ, D SPIRA, M ZERWAS, PM TI QCD CORRECTIONS TO HIGGS-BOSON PRODUCTION AT PROTON-PROTON COLLIDERS SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-ENERGY COLLISIONS; DRELL-YAN PROCESS; QUANTUM CHROMODYNAMICS; PARTON DISTRIBUTIONS; TRANSVERSE-MOMENTUM; HADRONIC COLLISIONS; HEAVY QUARKS; DECAY; MASS AB Gluon fusion is the main production mechanism for Higgs bosons with masses up to several hundred GeV in pp collisions at the CERN Large Hadron Collider and Superconducting Super Collider. We present the QCD corrections to the fusion cross section for arbitrary Higgs boson and top quark mass values: gg --> H(g), gq --> Hq, and qqBAR --> Hg. The QCD corrections are positive and they increase the cross section sigma(pp --> H) by about a factor of 1.5 to 1.7. The analysis applies to the production of Higgs particles in the standard model and also to the production of the CP-even Higgs particles in extensions of the Higgs sector as required, for example, by supersymmetric theories. C1 RHEIN WESTFAL TH AACHEN,INST THEORET PHYS,W-5100 AACHEN,GERMANY. DESY,W-2000 HAMBURG 52,GERMANY. RP GRAUDENZ, D (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 44 TC 231 Z9 232 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 8 PY 1993 VL 70 IS 10 BP 1372 EP 1375 DI 10.1103/PhysRevLett.70.1372 PG 4 WC Physics, Multidisciplinary SC Physics GA KQ414 UT WOS:A1993KQ41400005 ER PT J AU ABE, F AMIDEI, D ANWAYWIESE, C APOLLINARI, G ATAC, M AUCHINCLOSS, P AZZI, P BADEN, AR BACCHETTA, N BADGETT, W BAILEY, MW BAMBERGER, A DEBARBARO, P BARBAROGALTIERI, A BARNES, VE BARNETT, BA BAUER, G BAUMANN, T BEDESCHI, F BEHRENDS, S BELFORTE, S BELLETTINI, G BELLINGER, J BENJAMIN, D BENLLOCH, J BENSINGER, J BERETVAS, A BERGE, JP BERTOLUCCI, S BIERY, K BHADRA, S BINKLEY, M BISELLO, D BLAIR, R BLOCKER, C BODEK, A BOLOGNESI, V BOOTH, AW BOSWELL, C BRANDENBURG, G BROWN, D BUCKLEYGEER, E BUDD, HS BUSETTO, G BYONWAGNER, A BYRUM, KL CAMPAGNARI, C CAMPBELL, M CANER, A CAREY, R CARITHERS, W CARLSMITH, D CARROLL, JT CASHMORE, R CASTRO, A CERVELLI, F CHADWICK, K CHAPMAN, J CHIARELLI, G CHINOWSKY, W CIHANGIR, S CLARK, AG COBAL, M CONNOR, D CONTRERAS, M COOPER, J CORDELLI, M CRANE, D CUNNINGHAM, JD DAY, C DEJONGH, F DELLAGNELLO, S DELLORSO, M DEMORTIER, L DENBY, B DERWENT, PF DEVLIN, T DIBITONTO, D DICKSON, M DRUCKER, RB EINSWEILER, K ELIAS, JE ELY, R ENO, S ERREDE, S ETCHEGOYEN, A FARHAT, B FELDMAN, GJ FLAUGHER, B FOSTER, GW FRANKLIN, M FREEMAN, J FRISCH, H FUESS, T FUKUI, Y GARFINKEL, AF GAUTHIER, A GEER, S GERDES, DW GIANNETTI, P GIOKARIS, N GIROMINI, P GLADNEY, L GOLD, M GONZALEZ, J GOULIANOS, K GRASSMANN, H GRIECO, GM GRINDLEY, R GROSSOPILCHER, C HABER, C HAHN, SR HANDLER, R HARA, K HARRAL, B HARRIS, RM HAUGER, SA HAUSER, J HAWK, C HESSING, T HOLLEBEEK, R HONG, S HOUK, G HU, P HUBBARD, B HUFFMAN, BT HUGHES, R HURST, P HUTH, J HYLEN, J INCAGLI, M INO, T ISO, H JENSEN, H JESSOP, CP JOHNSON, RP JOSHI, U KADEL, RW KAMON, T KANDA, S KARDELIS, DA KARLINER, I KEARNS, E KEEBLE, L KEPHART, R KESTEN, P KEUP, RM KEUTELIAN, H KIM, D KIM, SB KIM, SH KIM, YK KIRSCH, L KONDO, K KONIGSBERG, J KORDAS, K KOVACS, E KRASBERG, M KUHLMANN, SE KUNS, E LAASANEN, AT LAMMEL, S LAMOUREUX, JI LEONE, S LEWIS, JD LI, W LIMON, P LINDGREN, M LISS, TM LOCKYER, N LORETI, M LOW, EH LUCCHESI, D LUCHINI, CB LUKENS, P MAAS, P MAESHIMA, K MANGANO, M MARRINER, JP MARIOTTI, M MARKELOFF, R MARKOSKY, LA MATTINGLY, R MCINTYRE, P MENZIONE, A MESCHI, E MEYER, T MIKAMO, S MILLER, M MIMASHI, T MISCETTI, S MISHINA, M MIYASHITA, S MORITA, Y MOULDING, S MUELLER, J MUKHERJEE, A MULLER, T NAKAE, LF NAKANO, I NELSON, C NEUBERGER, D NEWMANHOLMES, C NG, JST NINOMIYA, M NODULMAN, L OGAWA, S PAOLETTI, R PAPADIMITRIOU, V PARA, A PARE, E PARK, S PATRICK, J PAULETTA, G PESCARA, L PHILLIPS, TJ PTOHOS, F PLUNKETT, R PONDROM, L PROUDFOOT, J PUNZI, G QUARRIE, D RAGAN, K REDLINGER, G RHOADES, J ROACH, M RIMONDI, F RISTORI, L ROBERTSON, WJ RODRIGO, T ROHALY, T ROODMAN, A SAKUMOTO, WK SANSONI, A SARD, RD SAVOYNAVARRO, A SCARPINE, V SCHLABACH, P SCHMIDT, EE SCHNEIDER, O SCHUB, MH SCHWITTERS, R SCRIBANO, A SEGLER, S SEIYA, Y SGANOS, G SHAPIRO, M SHAW, NM SHEAFF, M SHOCHET, M SIEGRIST, J SILL, A SINERVO, P SKARHA, J SLIWA, K SPIES, A SMITH, DA SNIDER, FD SONG, L SONG, T SPAHN, M SPHICAS, P STDENIS, R STANCO, L STEFANINI, A SULLIVAN, G SUMOROK, K SWARTZ, RL TAKANO, M TAKIKAWA, K TAREM, S TARTARELLI, F TETHER, S THERIOT, D TIMKO, M TIPTON, P TKACZYK, S TOLLESTRUP, A TONNISON, J TRISCHUK, W TSAY, Y TSENG, J TURINI, N UKEGAWA, F UNDERWOOD, D VEJCIK, S WAGNER, RG WAGNER, RL WAINER, N WALKER, RC WALSH, J WATTS, G WATTS, T WEBB, R WENDT, C WENZEL, H WESTER, WC WESTHUSING, T WHITE, SN WICKLUND, AB WICKLUND, E WILLIAMS, HH WINER, BL WOLINSKI, J WU, D WYSS, J YAGIL, A YASUOKA, K YE, Y YEH, GP YI, C YOH, J YOKOYAMA, M YUN, JC ZANETTI, A ZETTI, F ZHANG, S ZHANG, W ZUCCHELLI, S AF ABE, F AMIDEI, D ANWAYWIESE, C APOLLINARI, G ATAC, M AUCHINCLOSS, P AZZI, P BADEN, AR BACCHETTA, N BADGETT, W BAILEY, MW BAMBERGER, A DEBARBARO, P BARBAROGALTIERI, A BARNES, VE BARNETT, BA BAUER, G BAUMANN, T BEDESCHI, F BEHRENDS, S BELFORTE, S BELLETTINI, G BELLINGER, J BENJAMIN, D BENLLOCH, J BENSINGER, J BERETVAS, A BERGE, JP BERTOLUCCI, S BIERY, K BHADRA, S BINKLEY, M BISELLO, D BLAIR, R BLOCKER, C BODEK, A BOLOGNESI, V BOOTH, AW BOSWELL, C BRANDENBURG, G BROWN, D BUCKLEYGEER, E BUDD, HS BUSETTO, G BYONWAGNER, A BYRUM, KL CAMPAGNARI, C CAMPBELL, M CANER, A CAREY, R CARITHERS, W CARLSMITH, D CARROLL, JT CASHMORE, R CASTRO, A CERVELLI, F CHADWICK, K CHAPMAN, J CHIARELLI, G CHINOWSKY, W CIHANGIR, S CLARK, AG COBAL, M CONNOR, D CONTRERAS, M COOPER, J CORDELLI, M CRANE, D CUNNINGHAM, JD DAY, C DEJONGH, F DELLAGNELLO, S DELLORSO, M DEMORTIER, L DENBY, B DERWENT, PF DEVLIN, T DIBITONTO, D DICKSON, M DRUCKER, RB EINSWEILER, K ELIAS, JE ELY, R ENO, S ERREDE, S ETCHEGOYEN, A FARHAT, B FELDMAN, GJ FLAUGHER, B FOSTER, GW FRANKLIN, M FREEMAN, J FRISCH, H FUESS, T FUKUI, Y GARFINKEL, AF GAUTHIER, A GEER, S GERDES, DW GIANNETTI, P GIOKARIS, N GIROMINI, P GLADNEY, L GOLD, M GONZALEZ, J GOULIANOS, K GRASSMANN, H GRIECO, GM GRINDLEY, R GROSSOPILCHER, C HABER, C HAHN, SR HANDLER, R HARA, K HARRAL, B HARRIS, RM HAUGER, SA HAUSER, J HAWK, C HESSING, T HOLLEBEEK, R HONG, S HOUK, G HU, P HUBBARD, B HUFFMAN, BT HUGHES, R HURST, P HUTH, J HYLEN, J INCAGLI, M INO, T ISO, H JENSEN, H JESSOP, CP JOHNSON, RP JOSHI, U KADEL, RW KAMON, T KANDA, S KARDELIS, DA KARLINER, I KEARNS, E KEEBLE, L KEPHART, R KESTEN, P KEUP, RM KEUTELIAN, H KIM, D KIM, SB KIM, SH KIM, YK KIRSCH, L KONDO, K KONIGSBERG, J KORDAS, K KOVACS, E KRASBERG, M KUHLMANN, SE KUNS, E LAASANEN, AT LAMMEL, S LAMOUREUX, JI LEONE, S LEWIS, JD LI, W LIMON, P LINDGREN, M LISS, TM LOCKYER, N LORETI, M LOW, EH LUCCHESI, D LUCHINI, CB LUKENS, P MAAS, P MAESHIMA, K MANGANO, M MARRINER, JP MARIOTTI, M MARKELOFF, R MARKOSKY, LA MATTINGLY, R MCINTYRE, P MENZIONE, A MESCHI, E MEYER, T MIKAMO, S MILLER, M MIMASHI, T MISCETTI, S MISHINA, M MIYASHITA, S MORITA, Y MOULDING, S MUELLER, J MUKHERJEE, A MULLER, T NAKAE, LF NAKANO, I NELSON, C NEUBERGER, D NEWMANHOLMES, C NG, JST NINOMIYA, M NODULMAN, L OGAWA, S PAOLETTI, R PAPADIMITRIOU, V PARA, A PARE, E PARK, S PATRICK, J PAULETTA, G PESCARA, L PHILLIPS, TJ PTOHOS, F PLUNKETT, R PONDROM, L PROUDFOOT, J PUNZI, G QUARRIE, D RAGAN, K REDLINGER, G RHOADES, J ROACH, M RIMONDI, F RISTORI, L ROBERTSON, WJ RODRIGO, T ROHALY, T ROODMAN, A SAKUMOTO, WK SANSONI, A SARD, RD SAVOYNAVARRO, A SCARPINE, V SCHLABACH, P SCHMIDT, EE SCHNEIDER, O SCHUB, MH SCHWITTERS, R SCRIBANO, A SEGLER, S SEIYA, Y SGANOS, G SHAPIRO, M SHAW, NM SHEAFF, M SHOCHET, M SIEGRIST, J SILL, A SINERVO, P SKARHA, J SLIWA, K SPIES, A SMITH, DA SNIDER, FD SONG, L SONG, T SPAHN, M SPHICAS, P STDENIS, R STANCO, L STEFANINI, A SULLIVAN, G SUMOROK, K SWARTZ, RL TAKANO, M TAKIKAWA, K TAREM, S TARTARELLI, F TETHER, S THERIOT, D TIMKO, M TIPTON, P TKACZYK, S TOLLESTRUP, A TONNISON, J TRISCHUK, W TSAY, Y TSENG, J TURINI, N UKEGAWA, F UNDERWOOD, D VEJCIK, S WAGNER, RG WAGNER, RL WAINER, N WALKER, RC WALSH, J WATTS, G WATTS, T WEBB, R WENDT, C WENZEL, H WESTER, WC WESTHUSING, T WHITE, SN WICKLUND, AB WICKLUND, E WILLIAMS, HH WINER, BL WOLINSKI, J WU, D WYSS, J YAGIL, A YASUOKA, K YE, Y YEH, GP YI, C YOH, J YOKOYAMA, M YUN, JC ZANETTI, A ZETTI, F ZHANG, S ZHANG, W ZUCCHELLI, S TI COMPARISON OF JET PRODUCTION IN (P)OVER-BAR-P COLLISIONS AT ROOT-S = 546 AND 1800 GEV SO PHYSICAL REVIEW LETTERS LA English DT Article ID CROSS-SECTION; PBARP COLLISIONS; COLLIDER AB Inclusive jet cross sections have been measured in ppBAR collisions at square-root s = 546 and 1800 GeV, using the Collider Detector at Fermilab. The ratio of jet cross sections is compared to predictions from simple scaling and O(alpha(s)3) QCD. Our data exclude scaling and lie (1.5-2.4)sigma below a range of QCD predictions. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. BRANDEIS UNIV,WALTHAM,MA 02254. UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024. UNIV CHICAGO,CHICAGO,IL 60637. DUKE UNIV,DURHAM,NC 27706. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. IST NAZL FIS NUCL,LAB NAZL FRASCATI,FRASCATI,ITALY. HARVARD UNIV,CAMBRIDGE,MA 02138. UNIV ILLINOIS,URBANA,IL 61801. JOHNS HOPKINS UNIV,BALTIMORE,MD 21218. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. MIT,CAMBRIDGE,MA 02139. UNIV MICHIGAN,ANN ARBOR,MI 48109. UNIV PADUA,IST NAZL FIS NUCL,SEZ PADOVA,I-35131 PADUA,ITALY. UNIV PENN,PHILADELPHIA,PA 19104. UNIV PISA,IST NAZL FIS NUCL,I-56100 PISA,ITALY. SCUOLA NORMALE SUPER PISA,I-56100 PISA,ITALY. PURDUE UNIV,W LAFAYETTE,IN 47907. UNIV ROCHESTER,ROCHESTER,NY. ROCKEFELLER UNIV,NEW YORK,NY 10021. RUTGERS STATE UNIV,PISCATAWAY,NJ 08854. TEXAS A&M UNIV SYST,COLL STN,TX 77843. UNIV TSUKUBA,TSUKUBA,IBARAKI 305,JAPAN. TUFTS UNIV,MEDFORD,MA 02155. UNIV WISCONSIN,MADISON,WI 53706. RP ABE, F (reprint author), KEK,IBARAKI,JAPAN. RI St.Denis, Richard/C-8997-2012; Chiarelli, Giorgio/E-8953-2012; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Kim, Soo-Bong/B-7061-2014 OI Chiarelli, Giorgio/0000-0001-9851-4816; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; NR 12 TC 51 Z9 51 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 8 PY 1993 VL 70 IS 10 BP 1376 EP 1380 DI 10.1103/PhysRevLett.70.1376 PG 5 WC Physics, Multidisciplinary SC Physics GA KQ414 UT WOS:A1993KQ41400006 ER PT J AU FRABETTI, PL CHEUNG, HWK CUMALAT, JP DALLAPICCOLA, C GINKEL, JF GREENE, SV JOHNS, WE NEHRING, MS BUTLER, JN CIHANGIR, S GAINES, I GARREN, L GARBINCIUS, PH GOURLAY, SA HARDING, DJ KASPER, P KREYMER, A LEBRUN, P SHUKLA, S BIANCO, S FABBRI, FL SARWAR, S ZALLO, A CULBERTSON, R GARDNER, RW GREENE, R WISS, J ALIMONTI, G BELLINI, G CACCIANIGA, B CINQUINI, L DICORATO, M GIAMMARCHI, M INZANI, P LEVERARO, F MALVEZZI, S MENASCE, D MERONI, E MORONI, L PEDRINI, D PERASSO, L SALA, A SALA, S TORRETTA, D VITTONE, M BUCHHOLZ, D CLAES, D GOBBI, B OREILLY, B BISHOP, JM CASON, NM KENNEDY, CJ KIM, GN LIN, TF PUSELJIC, DL RUCHTI, RC SHEPHARD, WD SWIATEK, JA WU, ZY ARENA, V BOCA, G CASTOLDI, C DIAFERIA, R GIANINI, G RATTI, SP RICCARDI, C VITULO, P LOPEZ, A GRIM, GP PAOLONE, VS YAGER, PM WILSON, JR SHELDON, PD DAVENPORT, F FILASETTA, JF BLACKETT, GR PISHARODY, M HANDLER, T CHEON, BG KANG, JS KIM, KY AF FRABETTI, PL CHEUNG, HWK CUMALAT, JP DALLAPICCOLA, C GINKEL, JF GREENE, SV JOHNS, WE NEHRING, MS BUTLER, JN CIHANGIR, S GAINES, I GARREN, L GARBINCIUS, PH GOURLAY, SA HARDING, DJ KASPER, P KREYMER, A LEBRUN, P SHUKLA, S BIANCO, S FABBRI, FL SARWAR, S ZALLO, A CULBERTSON, R GARDNER, RW GREENE, R WISS, J ALIMONTI, G BELLINI, G CACCIANIGA, B CINQUINI, L DICORATO, M GIAMMARCHI, M INZANI, P LEVERARO, F MALVEZZI, S MENASCE, D MERONI, E MORONI, L PEDRINI, D PERASSO, L SALA, A SALA, S TORRETTA, D VITTONE, M BUCHHOLZ, D CLAES, D GOBBI, B OREILLY, B BISHOP, JM CASON, NM KENNEDY, CJ KIM, GN LIN, TF PUSELJIC, DL RUCHTI, RC SHEPHARD, WD SWIATEK, JA WU, ZY ARENA, V BOCA, G CASTOLDI, C DIAFERIA, R GIANINI, G RATTI, SP RICCARDI, C VITULO, P LOPEZ, A GRIM, GP PAOLONE, VS YAGER, PM WILSON, JR SHELDON, PD DAVENPORT, F FILASETTA, JF BLACKETT, GR PISHARODY, M HANDLER, T CHEON, BG KANG, JS KIM, KY TI MEASUREMENT OF THE MASS AND LIFETIME OF THE XI-C+ SO PHYSICAL REVIEW LETTERS LA English DT Article AB Measurements of the mass and lifetime of the XI(c)+ decaying into XI- pi+pi+ are presented. The data were accumulated by the Fermilab high-energy photoproduction experiment E687. The mass of the XI(c)+ is measured to be 2464.4+/-2.0+/-1.4 MeV/c2 and the lifetime is measured to be 0.41(-0.08)+0.11+/-0.02 ps. C1 IST NAZL FIS NUCL,BOLOGNA,ITALY. UNIV COLORADO,BOULDER,CO 80309. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. IST NAZL FIS NUCL,LAB NAZL FRASCATI,I-00044 FRASCATI,ITALY. UNIV ILLINOIS,URBANA,IL 61801. UNIV MILAN,DIPARTIMENTO FIS,I-20133 MILAN,ITALY. NATL INST NUCL PHYS,MILAN,ITALY. NORTHWESTERN UNIV,EVANSTON,IL 60208. UNIV NOTRE DAME,NOTRE DAME,IN 46556. UNIV PAVIA,DIPARTIMENTO FIS,I-27100 PAVIA,ITALY. IST NAZL FIS NUCL,I-27100 PAVIA,ITALY. UNIV PUERTO RICO,MAYAGUEZ,PR 00708. UNIV CALIF DAVIS,DAVIS,CA 95616. UNIV S CAROLINA,COLUMBIA,SC 29208. VANDERBILT UNIV,NASHVILLE,TN 37235. UNIV N CAROLINA,ASHEVILLE,NC 28804. NO KENTUCKY UNIV,HIGHLAND HTS,KY 41076. UNIV TENNESSEE,KNOXVILLE,TN 37996. KOREA UNIV,SEOUL 136701,SOUTH KOREA. RP FRABETTI, PL (reprint author), UNIV BOLOGNA,DIPARTIMENTO FIS,I-40126 BOLOGNA,ITALY. NR 8 TC 21 Z9 21 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 8 PY 1993 VL 70 IS 10 BP 1381 EP 1384 DI 10.1103/PhysRevLett.70.1381 PG 4 WC Physics, Multidisciplinary SC Physics GA KQ414 UT WOS:A1993KQ41400007 ER PT J AU ABBOTT, T AKIBA, Y BEAVIS, D BLOOMER, MA BOND, PD CHASMAN, C CHEN, Z CHU, YY COLE, BA COSTALES, JB CRAWFORD, HJ CUMMING, JB DEBBE, R DUEK, E ENGELAGE, J FUNG, SY GUSHUE, S HAMAGAKI, H HANSEN, O HAYANO, RS HAYASHI, S HAUSTEIN, PE HOMMA, S HUANG, HZ IKEDA, Y JURICIC, I KANG, J KATCOFF, S KAUFMAN, S KIMURA, K KITAMURA, K KURITA, K LEDOUX, RJ LEVINE, MJ MIAKE, Y MORSE, RJ MOSKOWITZ, B NAGAMIYA, S OLNESS, J PARSONS, CG REMSBERG, LP SAKURAI, H SARABURA, M STANKUS, P STEADMAN, SG STEPHANS, GSF SUGITATE, T TANNENBAUM, MJ VANDIJK, JH VIDEBAEK, F VIENT, M VINCENT, P VUTSADAKIS, V WEGNER, HE WOODRUFF, DS WU, YD ZAJC, W AF ABBOTT, T AKIBA, Y BEAVIS, D BLOOMER, MA BOND, PD CHASMAN, C CHEN, Z CHU, YY COLE, BA COSTALES, JB CRAWFORD, HJ CUMMING, JB DEBBE, R DUEK, E ENGELAGE, J FUNG, SY GUSHUE, S HAMAGAKI, H HANSEN, O HAYANO, RS HAYASHI, S HAUSTEIN, PE HOMMA, S HUANG, HZ IKEDA, Y JURICIC, I KANG, J KATCOFF, S KAUFMAN, S KIMURA, K KITAMURA, K KURITA, K LEDOUX, RJ LEVINE, MJ MIAKE, Y MORSE, RJ MOSKOWITZ, B NAGAMIYA, S OLNESS, J PARSONS, CG REMSBERG, LP SAKURAI, H SARABURA, M STANKUS, P STEADMAN, SG STEPHANS, GSF SUGITATE, T TANNENBAUM, MJ VANDIJK, JH VIDEBAEK, F VIENT, M VINCENT, P VUTSADAKIS, V WEGNER, HE WOODRUFF, DS WU, YD ZAJC, W TI AZIMUTHAL ASYMMETRIES OF PARTICLES EMITTED IN RELATIVISTIC HEAVY-ION COLLISIONS SO PHYSICAL REVIEW LETTERS LA English DT Article AB Experimental particle yield ratios from 14.6A-GeV/c Si-28 interactions with nuclei at intermediate impact parameters are correlated with the orientation of the transverse momentum of projectile fragments. The pi+/-/p ratio increases and the (d + t)/p ratio decreases when fragments are deflected toward the observing spectrometer. Asymmetries are confined to the target rapidity region. Assuming a spectator participant model, these results suggest the presence of significant rescattering of particles with dependences on the collision geometry. C1 UNIV CALIF RIVERSIDE,RIVERSIDE,CA 92521. UNIV TOKYO,INST NUCL STUDY,TOKYO 108,JAPAN. BROOKHAVEN NATL LAB,UPTON,NY 11973. MIT,CAMBRIDGE,MA 02139. UNIV CALIF BERKELEY,SPACE SCI LAB,BERKELEY,CA 94720. UNIV TOKYO,DEPT PHYS,TOKYO 113,JAPAN. KYUSHU UNIV,FUKUOKA 812,JAPAN. COLUMBIA UNIV,NEW YORK,NY 10027. NEVIS LABS,IRVINGTON,NY 10533. ARGONNE NATL LAB,ARGONNE,IL 60439. HIROSHIMA UNIV,HIROSHIMA 730,JAPAN. RI Duek, Eliana/J-2499-2012; Cumming, James/I-3358-2013; SAKURAI, HIROYOSHI/G-5085-2014; Hayano, Ryugo/F-7889-2012; HAMAGAKI, HIDEKI/G-4899-2014 OI Cumming, James/0000-0001-6930-0958; Hayano, Ryugo/0000-0002-1214-7806; NR 11 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 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 8 PY 1993 VL 70 IS 10 BP 1393 EP 1396 DI 10.1103/PhysRevLett.70.1393 PG 4 WC Physics, Multidisciplinary SC Physics GA KQ414 UT WOS:A1993KQ41400010 ER PT J AU COFFEY, D COFFEY, L AF COFFEY, D COFFEY, L TI QUASI-PARTICLE DECAY EFFECTS IN THE SUPERCONDUCTING DENSITY OF STATES - EVIDENCE FOR D-WAVE PAIRING IN THE CUPRATES SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTIVITY; HIGH-TC SUPERCONDUCTIVITY; SPIN FLUCTUATIONS; BAG MECHANISM AB Recent tunneling and photoemission data on the cuprate oxide superconductors may provide important information in choosing between proposed models for the superconducting order parameter in these materials. We show that corrections to the weak coupling mean-field approximation for a superconductor lead to different frequency thresholds for the spontaneous decay of the Bogoliubov quasiparticles for different order parameter symmetries and that these effects may be seen in the superconductor-insulator-superconductor tunneling conductance. Comparison with the recent data indicates that a d(x2-y2), rather than an s-wave, order parameter is a likely candidate for describing the cuprates. C1 IIT,DEPT PHYS,CHICAGO,IL 60616. RP COFFEY, D (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,LOS ALAMOS,NM 87545, USA. NR 29 TC 66 Z9 66 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 8 PY 1993 VL 70 IS 10 BP 1529 EP 1532 DI 10.1103/PhysRevLett.70.1529 PG 4 WC Physics, Multidisciplinary SC Physics GA KQ414 UT WOS:A1993KQ41400044 ER PT J AU COOPER, SL NYHUS, P REZNIK, D KLEIN, MV LEE, WC GINSBERG, DM VEAL, BW PAULIKAS, AP DABROWSKI, B AF COOPER, SL NYHUS, P REZNIK, D KLEIN, MV LEE, WC GINSBERG, DM VEAL, BW PAULIKAS, AP DABROWSKI, B TI INTERBILAYER CHARGE DYNAMICS IN YBA2CU3O6+X SO PHYSICAL REVIEW LETTERS LA English DT Article ID ANISOTROPY; RESISTIVITY AB We present optical reflectivity and Raman scattering studies of YBa2Cu3O6+x as a function of doping using c-axis polarized light. The c-axis optical response of YBa2Cu3O7 is characterized by a Drude-like conductivity and an electronic Raman continuum, indicating a weak coupling between adjacent CuO2 bilayers which is mediated by the CuO chains. With reduced doping, the c-axis Drude and continuum responses rapidly decrease, revealing a strong sensitivity of the interbilayer coupling strength to the removal of oxygen from the chain sites. We suggest that interbilayer charge transport in YBa2Cu3O6+x may be governed by carrier scattering from in-plane fluctuations. C1 UNIV ILLINOIS,MAT RES LAB,URBANA,IL 61801. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. NO ILLINOIS UNIV,DEPT PHYS,DE KALB,IL 60115. RP COOPER, SL (reprint author), UNIV ILLINOIS,DEPT PHYS,URBANA,IL 61801, USA. NR 13 TC 65 Z9 65 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 8 PY 1993 VL 70 IS 10 BP 1533 EP 1536 DI 10.1103/PhysRevLett.70.1533 PG 4 WC Physics, Multidisciplinary SC Physics GA KQ414 UT WOS:A1993KQ41400045 ER PT J AU KUIPER, P SEARLE, BG RUDOLF, P TJENG, LH CHEN, CT AF KUIPER, P SEARLE, BG RUDOLF, P TJENG, LH CHEN, CT TI X-RAY MAGNETIC DICHROISM OF ANTIFERROMAGNET FE2O3 - THE ORIENTATION OF MAGNETIC-MOMENTS OBSERVED BY FE 2P X-RAY ABSORPTION-SPECTROSCOPY SO PHYSICAL REVIEW LETTERS LA English DT Article ID NICKEL; SPECTRA; EDGES AB We report strong magnetic linear dichroism at the Fe L2,3 edge of the antiferromagnet Fe2O3 (hematite). The relative difference in absorption for light polarized parallel and perpendicular to the magnetic moment is as high as 40% at the Fe L2 edge. The spectra are in excellent agreement with calculations of magnetic dichroism for Fe3+ (3d5). The magnetic origin of this dichroism is demonstrated by the Morin transition at almost-equal-to 10-degrees-C, where the moments in Fe2O3 rotate by 90-degrees. Magnetic linear dichroism may be applied to measure the spin orientation in thin films and multilayers, and to image magnetic domains. C1 UNIV GRONINGEN,CTR MAT SCI,DEPT APPL & SOLID STATE PHYS,9747 AG GRONINGEN,NETHERLANDS. AT&T BELL LABS,MURRAY HILL,NJ 07974. RP KUIPER, P (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. RI Kuiper, Pieter/A-6806-2012; Rudolf, Petra/E-6434-2014 OI Rudolf, Petra/0000-0002-4418-1769 NR 23 TC 168 Z9 170 U1 1 U2 26 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 8 PY 1993 VL 70 IS 10 BP 1549 EP 1552 DI 10.1103/PhysRevLett.70.1549 PG 4 WC Physics, Multidisciplinary SC Physics GA KQ414 UT WOS:A1993KQ41400049 ER PT J AU SHEN, ZX DESSAU, DS WELLS, BO KING, DM SPICER, WE ARKO, AJ MARSHALL, D LOMBARDO, LW KAPITULNIK, A DICKINSON, P DONIACH, S DICARLO, J LOESER, AG PARK, CH AF SHEN, ZX DESSAU, DS WELLS, BO KING, DM SPICER, WE ARKO, AJ MARSHALL, D LOMBARDO, LW KAPITULNIK, A DICKINSON, P DONIACH, S DICARLO, J LOESER, AG PARK, CH TI ANOMALOUSLY LARGE GAP ANISOTROPY IN THE A-B PLANE OF BI2SR2CACU2O8+DELTA SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTIVITY; ANGLE-RESOLVED-PHOTOEMISSION; HIGH-TC SUPERCONDUCTIVITY; MEAN-FIELD THEORY; SUPEREXCHANGE MECHANISM; MODEL AB Superconducting gap anisotropy at least an order of magnitude larger than that of the conventional superconductors has been observed in the a-b plane of Bi2Sr2CaCu2O8+delta in angle-resolved photoemission spectroscopy. For samples with T(c) of 88 K, the gap size reaches a maximum of approximately 20 meV along the Cu-O bond direction, and a minimum of much smaller or vanishing magnitude 45-degrees away. The experimental data are discussed within the context of various theoretical models. In particular, a detailed comparison with what is expected from a superconductor with a d(x2-y2) order parameter is carried out, yielding a consistent picture. C1 STANFORD UNIV,SOLID STATE ELECTR LAB,STANFORD,CA 94305. STANFORD UNIV,STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94305. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP SHEN, ZX (reprint author), STANFORD UNIV,DEPT APPL PHYS,STANFORD,CA 94305, USA. NR 28 TC 757 Z9 760 U1 1 U2 29 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 8 PY 1993 VL 70 IS 10 BP 1553 EP 1556 DI 10.1103/PhysRevLett.70.1553 PG 4 WC Physics, Multidisciplinary SC Physics GA KQ414 UT WOS:A1993KQ41400050 ER PT J AU FOIAS, C MANLEY, OP TEMAM, R AF FOIAS, C MANLEY, OP TEMAM, R TI BOUNDS FOR THE MEAN DISSIPATION OF 2-D ENSTROPHY AND 3-D ENERGY IN TURBULENT FLOWS SO PHYSICS LETTERS A LA English DT Article ID NAVIER-STOKES EQUATIONS AB A rigorous statistical definition of the average enstrophy dissipation in two-dimensional flows, and of the average energy dissipation in three-dimensional flows leads to the establishment of rigorous lower bounds on the corresponding cut-off wave numbers. That in turn permits us to conjecture the corresponding lower bounds on the number of degrees of freedom in those flows. For a particular commonly considered strong body force driving a turbulent two-dimensional flow, an improved upper bound on the number of degrees of freedom is found. C1 US DOE,WASHINGTON,DC 20545. CNRS,ANAL NUMER LAB,F-92405 ORSAY,FRANCE. INDIANA UNIV,DEPT MATH,BLOOMINGTON,IN 47405. UNIV PARIS 11,F-91405 ORSAY,FRANCE. RP FOIAS, C (reprint author), INDIANA UNIV,DEPT MATH,BLOOMINGTON,IN 47405, USA. NR 7 TC 17 Z9 17 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD MAR 8 PY 1993 VL 174 IS 3 BP 210 EP 215 DI 10.1016/0375-9601(93)90760-W PG 6 WC Physics, Multidisciplinary SC Physics GA KQ113 UT WOS:A1993KQ11300007 ER PT J AU BENZEL, S GE, Z SCOVEL, C AF BENZEL, S GE, Z SCOVEL, C TI ELEMENTARY CONSTRUCTION OF HIGHER-ORDER LIE-POISSON INTEGRATORS SO PHYSICS LETTERS A LA English DT Article ID MANY-BODY THEORIES; SYMPLECTIC INTEGRATION; SYSTEMS AB Higher order Lie-Poisson integrators generated from first order ones are described and tested on an Euler equation on su (4). The technique is based upon the method of Suzuki and Yoshida combined with an observation of Scovel. This technique works for any type of autonomous ordinary differential equation, not just Hamiltonian systems, and is especially useful in generating higher order methods in an elementary manner. In particular, up to now, only first order Lie-Poisson integrators were available for Lie algebras that were not regular quadratic. This technique should also be useful in the development of higher order momentum preserving symplectic integrators such as in Patrick's [23] study of two axially symmetric coupled rigid bodies. C1 FIELDS INST RES MATH SCI,WATERLOO N2L 5Z5,ON,CANADA. LOS ALAMOS NATL LAB,COMP RES GRP,LOS ALAMOS,NM 87545. RP BENZEL, S (reprint author), UNIV CALIF BERKELEY,DEPT MATH,BERKELEY,CA 94720, USA. NR 23 TC 9 Z9 9 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD MAR 8 PY 1993 VL 174 IS 3 BP 229 EP 232 DI 10.1016/0375-9601(93)90763-P PG 4 WC Physics, Multidisciplinary SC Physics GA KQ113 UT WOS:A1993KQ11300010 ER PT J AU SHANKLAND, TJ JOHNSON, PA HOPSON, TM AF SHANKLAND, TJ JOHNSON, PA HOPSON, TM TI ELASTIC WAVE ATTENUATION AND VELOCITY OF BEREA SANDSTONE MEASURED IN THE FREQUENCY-DOMAIN SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SATURATED ROCKS; SEISMIC-WAVES; DRY; REFLECTOMETRY AB Using measurements in the frequency domain we have measured quality factor Q and travel times of direct and side-reflected elastic waves in a 1.8 m long sample of Berea sandstone. The frequency domain travel time (FDTT) method produces the continuous-wave (cw) response of a propagating wave by stepwise sweeping frequency of a driving source and detecting amplitude and phase of the received signal in reference to the source. Each separate travel path yields a characteristic repetition cycle in frequency space as its wave vector-distance product is stepped; an inverse fast Fourier transform (IFFT) reveals the corresponding travel time at the group velocity. Because arrival times of direct and reflected elastic waves appear as spikes along the time axis, travel times can be obtained precisely, and different arrivals can be clearly separated. Q can be determined from the amplitude vs. frequency response of each peak as obtained from a moving window IFFT of the frequency-domain signal. In this sample at ambient conditions compressional velocity V(P) is 2380 m/s and Q(P) is 55. C1 INST PHYS GLOBE,DEPT GEOMATERIAUX,F-75252 PARIS 05,FRANCE. RP SHANKLAND, TJ (reprint author), LOS ALAMOS NATL LAB,DIV EARTH & ENVIRONM SCI,MS-D443,LOS ALAMOS,NM 87545, USA. NR 15 TC 6 Z9 6 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 5 PY 1993 VL 20 IS 5 BP 391 EP 394 DI 10.1029/92GL02758 PG 4 WC Geosciences, Multidisciplinary SC Geology GA KR866 UT WOS:A1993KR86600015 ER PT J AU WALTER, WR AF WALTER, WR TI SOURCE PARAMETERS OF THE JUNE 29, 1992 LITTLE SKULL MOUNTAIN EARTHQUAKE FROM COMPLETE REGIONAL WAVE-FORMS AT A SINGLE STATION SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SURFACE-WAVES AB The June 29, 1992, m(b)=5.5, Little Skull Mountain earthquake occurred 20 km southeast of Yucca Mountain within the boundaries of the Nevada Test Site. This event was recorded at a very broadband station located about 310 km to the east at Kanab, Utah. Both body and surface waves from this single station were used in a grid search technique for the best fitting double couple moment tensor. The technique minimizes the misfit between reflectivity generated complete synthetic seismograms and the three-component displacement dam via a search over the strike, dip and rake of the source. In the passband of 50-15 s period, the grid search results in a well defined, nearly pure normal mechanism with a strike of 35-degrees, a dip of 54-degrees, a rake of -87-degrees, and a seismic moment of 4.1 x 10(17) N-m. Applying the same technique to the large aftershock on July 5, 1992 we obtain a somewhat less well defined minimum with a strike of 358-degrees, a dip of 36-degrees, a rake of -177-degrees, and a moment of 4.3 x 10(15) N-m. The minimum-compression axes of these mechanisms are consistent with northwest-southeast extension in the Basin and Range. RP WALTER, WR (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT EARTH SCI,LIVERMORE,CA 94550, USA. RI Walter, William/C-2351-2013 OI Walter, William/0000-0002-0331-0616 NR 14 TC 49 Z9 53 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 5 PY 1993 VL 20 IS 5 BP 403 EP 406 DI 10.1029/92GL03031 PG 4 WC Geosciences, Multidisciplinary SC Geology GA KR866 UT WOS:A1993KR86600018 ER PT J AU SANCAR, A HEARST, JE AF SANCAR, A HEARST, JE TI MOLECULAR MATCHMAKERS SO SCIENCE LA English DT Article ID POLYMERASE ACCESSORY PROTEINS; EARLY TRANSCRIPTION FACTOR; CELL NUCLEAR ANTIGEN; ESCHERICHIA-COLI; DNA-POLYMERASE; ATP HYDROLYSIS; REPLICATION; INITIATION; REPAIR; BACTERIOPHAGE-T4 AB Molecular matchmakers are a class of proteins that use the energy released from the hydrolysis of adenosine triphosphate to cause a conformational change in one or both components of a DNA binding protein pair to promote formation of a metastable DNA-protein complex. After matchmaking the matchmaker dissociates from the complex, permitting the matched protein to engage in other protein-protein interactions to bring about the effector function. Matchmaking is most commonly used under circumstances that require targeted, high-avidity DNA binding without relying solely on sequence specificity. Molecular matchmaking is an extensively used mechanism in repair, replication, and transcription and most likely in recombination and transposition reactions, too. C1 LAWRENCE BERKELEY LAB,DIV CHEM BIODYNAM,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DEPT CHEM,BERKELEY,CA 94720. RP SANCAR, A (reprint author), UNIV N CAROLINA,SCH MED,DEPT BIOCHEM & BIOPHYS,CHAPEL HILL,NC 27599, USA. FU NIGMS NIH HHS [GM32833] NR 60 TC 155 Z9 156 U1 0 U2 3 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD MAR 5 PY 1993 VL 259 IS 5100 BP 1415 EP 1420 DI 10.1126/science.8451638 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA KP978 UT WOS:A1993KP97800025 PM 8451638 ER PT J AU HELMENSTINE, AM LI, YS VODINH, T AF HELMENSTINE, AM LI, YS VODINH, T TI SURFACE-ENHANCED RAMAN-SCATTERING ANALYSIS OF ETHENO ADDUCTS OF ADENINE SO VIBRATIONAL SPECTROSCOPY LA English DT Article DE RAMAN SPECTROMETRY; ADENINE; DNA; ETHENO ADDUCTS; VINYL CHLORIDE ID NUCLEIC-ACID BASES; BENZOPYRENE-DNA ADDUCTS; SILVER; SERS AB We report surface-enhanced Raman spectroscopy (SERS) detection and analysis of several etheno adducts formed from the metabolism of vinyl chloride: 1,N6-ethenoadenine, 1,N6-ethenoadenosine, and 1,N6-etheno-2'-deoxyadenosine. Spectra of the etheno adducts are compared with unmodified adenine and 2'-deoxyadenosine. Chemical group assignments are made for the SERS peaks of these adducts and the limit at which SERS can detect the adducts is assessed. These assignments are compared with SERS analyses of nucleotides and nucleosides. C1 OAK RIDGE NATL LAB,DIV HLTH & SAFETY RES,ADV MONITORING DEV GRP,OAK RIDGE,TN 37831. UNIV TENNESSEE,OAK RIDGE GRAD SCH BIOMED SCI,DIV BIOL,OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. NR 16 TC 7 Z9 7 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-2031 J9 VIB SPECTROSC JI Vib. Spectrosc. PD MAR 5 PY 1993 VL 4 IS 3 BP 359 EP 364 DI 10.1016/0924-2031(93)80009-5 PG 6 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA KQ629 UT WOS:A1993KQ62900009 ER PT J AU BRINKER, CJ WARD, TL SEHGAL, R RAMAN, NK HIETALA, SL SMITH, DM HUA, DW HEADLEY, TJ AF BRINKER, CJ WARD, TL SEHGAL, R RAMAN, NK HIETALA, SL SMITH, DM HUA, DW HEADLEY, TJ TI ULTRAMICROPOROUS SILICA-BASED SUPPORTED INORGANIC MEMBRANES SO JOURNAL OF MEMBRANE SCIENCE LA English DT Article DE MICROPOROUS MEMBRANES; SILICA-BASED MEMBRANES; SOL-GEL PROCESS; PERMEABILITY ID ALUMINA AB Ultramicroporous (Pore radius < 10 angstrom) separation layers with thicknesses in the range of 200-1200 A were deposited from polymeric silicate sols onto commercial alumina supports using a dip-coating/casting procedure. The silicate sols were prepared using a two-step acid-catalyzed hydrolysis of tetraethoxysilane under pH conditions where the condensation rate is low, producing polymers of low fractal dimension which readily interpenetrate during film deposition to provide amorphous layers with extremely small pore sizes. At low aging times (t/t(gel) = 0.05), the acid catalyst concentration had a dramatic effect on the deposited membrane permeability. Using 1N HCl a discrete, featureless membrane layer was deposited on top of the mesoporous support (as revealed by TEM), while lower acid concentration (0.44 N) resulted in polymer penetration and filling of the support pores rather than the deposition of a discrete external layer. This was attributed to the effect of acid concentration on the polymer condensation rate during the final stages of membrane deposition and drying. Deposited membrane layer thickness was found to depend on sol aging time, solvent dilution, and dipping/casting time. Helium permeabilities for deposited layers were approximately 1000-2000 barrer. Measured reductions (65-90%) in the helium and nitrogen permeation rates upon membrane deposition indicated pore radii less than 10 angstrom for the deposited membrane layers. C1 UNIV NEW MEXICO,UNM NSF CTR MICROENGN CERAM,ALBUQUERQUE,NM 87131. RP BRINKER, CJ (reprint author), SANDIA NATL LABS,DEPT CERAM SYNTHESIS & INORGAN CHEM 1846,ALBUQUERQUE,NM 87185, USA. NR 16 TC 124 Z9 124 U1 0 U2 23 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0376-7388 J9 J MEMBRANE SCI JI J. Membr. Sci. PD MAR 4 PY 1993 VL 77 IS 2-3 BP 165 EP 179 DI 10.1016/0376-7388(93)85067-7 PG 15 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA KT411 UT WOS:A1993KT41100004 ER PT J AU MICHAEL, JV LIM, KP KUMARAN, SS KIEFER, JH AF MICHAEL, JV LIM, KP KUMARAN, SS KIEFER, JH TI THERMAL-DECOMPOSITION OF CARBON-TETRACHLORIDE SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID HIGH-TEMPERATURE PYROLYSIS; METHYL RADICALS; RATE CONSTANTS; SHOCK-WAVES; DISSOCIATION; KINETICS; CCL3; INCINERATION AB The first rate measurements of the thermal dissociation of CCl4 are reported. Three detection techniques were used in monitoring the reaction rate for various dilutions over a wide temperature range: (i) ARAS of product Cl atoms in reflected shock waves using 3.2-6.4 ppm of CCl4 in Ar over 1084-1705 K and 150-908 Torr, (ii) decay of CCl4 by molecular absorption of 0-atom resonance radiation in reflected shock waves using 48-173 PPM Of CC14 in Ar over 11 92-1733 K and 219-855 Torr, and (iii) laser schlieren density gradients in incident shock waves using 0.5 and 2% CCl4 in Kr over 1470-2186 K and 90-660 Torr. The second-order rates from ARAS and molecular absorption measurements for the bond fission reaction CCl4 --> CCl3 + Cl are in complete agreement with the laser schlieren results where they overlap. The temperature and pressure dependence of these rates is well characterized by Gorin model RRKM calculations using a current DELTAH-degrees-0 = 67.71 kcal/mol for E0, derived from DELTA(f)H-degrees-298 = 17.0 kcal/mol for CCl3. The low-pressure rate constant (k0) derived from this RRKM fit is log k0 (CM3/(mol s)) = 54.980 - 10.624 log T- 74.796 (kcal/mol)/2.303RT. These low-pressure rates require unusually large beta(c) corresponding to a [DELTAE]down = 1200 cm-1. This may be a general feature of chlorocarbon dissociations. The ARAS data indicate that two Cl atoms are ultimately produced for each CCl4 that dissociates, with the second Cl atom forming slower than the first. Here all the measurements are consistent with a further dissociation Of CC13, CC13 --> CCl2 + Cl, as the dominant source of secondary Cl-atom at a mte about 0. 1 that of the primary fission. C1 UNIV ILLINOIS,DEPT CHEM ENGN,CHICAGO,IL 60680. RP MICHAEL, JV (reprint author), ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439, USA. RI Michael, Joe/E-3907-2010 NR 37 TC 65 Z9 66 U1 2 U2 8 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 MAR 4 PY 1993 VL 97 IS 9 BP 1914 EP 1919 DI 10.1021/j100111a032 PG 6 WC Chemistry, Physical SC Chemistry GA KQ339 UT WOS:A1993KQ33900032 ER PT J AU ARMSTRONG, PA BELL, AT REIMER, JA AF ARMSTRONG, PA BELL, AT REIMER, JA TI COMPARISON OF THE DYNAMICS AND ORIENTATION OF CHEMISORBED BENZENE AND PYRIDINE ON GAMMA-MO2N SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID MAGNETIC-RESONANCE; NMR-SPECTROSCOPY; PT(111); HYDRODENITROGENATION; TRANSITION; CARBIDES; SURFACE; AG(111) AB Chemisorbed benzene and pyridine on high surface area (140-155 M2/g)gamma-Mo2N have been investigated by using temperature programmed desorption (TPD) and H-2-NMR Spectroscopy. NMR spectra obtained at 295 K indicate that a fraction of adsorbed benzene is static, a fraction rotates rapidly about the C6 axis of benzene, and a fraction translates rapidly in three dimensions. At 80 K benzene can no longer translate; that fraction which translates at 295 K undergoes only rapid rotational motion at 80 K. The uptake of benzene is 140 +/-50 mumol/g. Chemisorbed benzene is displaced completely by pyridine in a competitive adsorption experiment at 295 K. The uptake of pyridine at 295 K is 560 +/- 50 mumol/g, which is similar to the uptakes of ammonia and acetonitrile on gamma-Mo2N. Pyridine desorbs molecularly during a temperature ramp in two temperature ranges centered at 388 and 563 K. No other species desorb from gamma-Mo2N below 700 K. NMR experiments indicate that the majority of chemisorbed pyridine is static after adsorption at 295 K, while a fraction undergoes rapid motion. The absolute population of surface pyridine which is motional at 295 K remains constant after treatments at 295 and 493 K, while the static pyridine population falls after treatments above 295 K. The motion is consistent with incomplete rotations about the C2v axis of pyridine through an angle greater than 180-degrees. A model for the geometry of adsorbed pyridine consistent with this motion is proposed. C1 LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. NR 28 TC 9 Z9 9 U1 1 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 MAR 4 PY 1993 VL 97 IS 9 BP 1952 EP 1960 DI 10.1021/j100111a037 PG 9 WC Chemistry, Physical SC Chemistry GA KQ339 UT WOS:A1993KQ33900037 ER PT J AU AMOS, NA AVILA, C BAKER, WF BERTANI, M BLOCK, MM DIMITROYANNIS, DA EARTLY, DP ELLSWORTH, RW GIACOMELLI, G GOMEZ, B GOODMAN, JA GUSS, CM HOENEISEN, B LENNOX, AJ MONDARDINI, MR NEGRET, JP OREAR, J PRUSS, SM RUBINSTEIN, R SADR, S SANABRIA, JC SHUKLA, S SPAGNOLI, M VERONESI, I ZUCCHELLI, S AF AMOS, NA AVILA, C BAKER, WF BERTANI, M BLOCK, MM DIMITROYANNIS, DA EARTLY, DP ELLSWORTH, RW GIACOMELLI, G GOMEZ, B GOODMAN, JA GUSS, CM HOENEISEN, B LENNOX, AJ MONDARDINI, MR NEGRET, JP OREAR, J PRUSS, SM RUBINSTEIN, R SADR, S SANABRIA, JC SHUKLA, S SPAGNOLI, M VERONESI, I ZUCCHELLI, S TI DIFFRACTION DISSOCIATION IN (P)OVER-BAR-P COLLISIONS AT ROOT-S=1.8 TEV SO PHYSICS LETTERS B LA English DT Article ID TOTAL CROSS-SECTION; CERN SPS COLLIDER; = 1.8 TEV; ELASTIC-SCATTERING; ENERGIES; ISR AB We have studied single diffraction dissociation (ppBAR --> pXBAR) in proton-antiproton collisions at square-root s = 1.8 TeV, covering the ranges 3 less than or similar to M(X) less than or similar to 200 GeV and 0.05 less than or similar to Absolute value of t less than or similar to 0.11 (GeV/c)2. Parameterizing the production to be of the form dsigma/(dtdM(X)2) = (M(X)2)-alpha exp(bt), we obtain alpha = 1.13 +/- 0.07 and b = 10.5 +/- 1.8 (GeV/c)-2. The total single diffraction dissociation cross section is 2sigma(SD) = 8.1 +/- 1.7 mb. Comparisons are made to previous lower energy data. and to an earlier measurement by us at the same energy. C1 UNIV BOLOGNA,I-40126 BOLOGNA,ITALY. IST NAZL FIS NUCL,I-40126 BOLOGNA,ITALY. NORTHWESTERN UNIV,EVANSTON,IL 60201. UNIV MARYLAND,COLL PK,MD 20742. GEORGE MASON UNIV,FAIRFAX,VA 22030. UNIV LOS ANDES,BOGOTA,COLOMBIA. UNIV SAN FRANCISCO QUITO,QUITO,ECUADOR. CORNELL UNIV,ITHACA,NY 14853. RP AMOS, NA (reprint author), FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. NR 16 TC 51 Z9 52 U1 0 U2 1 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 MAR 4 PY 1993 VL 301 IS 2-3 BP 313 EP 316 DI 10.1016/0370-2693(93)90707-O PG 4 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA KP076 UT WOS:A1993KP07600027 ER PT J AU DUBOIS, DL KVIETOK, F DUBOIS, MR AF DUBOIS, DL KVIETOK, F DUBOIS, MR TI A MOLECULAR-ORBITAL COMPARISON OF MOLYBDENUM SULFUR DIMERS WITH SULFIDO LIGANDS BRIDGED BY CH2 AND FECP FRAGMENTS SO INORGANIC CHEMISTRY LA English DT Article ID COMPLEXES; HYDROGEN; REACTIVITIES; ACTIVATION; CLEAVAGE; BOND AB An extensive reactivity with hydrogen and unsaturated molecules has been characterized for the mu-sulfide ligands in (CPMO)2(mu-S)2S2CH2 (2). However, the bridging disulfide ligand in the heteronuclear cluster [(CPMO)2(mu-S2)(mu-S2FeCP)]+ (3) was not reactive toward hydrogen or olefins. Extended Huckel molecular orbital calculations have been carried out for 2 and for the hypothetical Fe-Mo cluster with bridging sulfides rather than a disulfide ligand [(CpMo)2(mu-S)2(S2FeCp)]+ (3'). The electronic structures of complexes 2 and 3' are analyzed in terms of the CP2Mo2S4 and methylene and the FeCp+ fragment orbitals, respectively. This approach leads to a qualitative understanding of the reasons for the structural and reactivity differences between 2 and 3. C1 UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RP DUBOIS, DL (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 24 TC 3 Z9 3 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAR 3 PY 1993 VL 32 IS 5 BP 561 EP 564 DI 10.1021/ic00057a012 PG 4 WC Chemistry, Inorganic & Nuclear SC Chemistry GA KQ051 UT WOS:A1993KQ05100012 ER PT J AU BERG, JM SATTELBERGER, AP MORRIS, DE VANDERSLUYS, WG FLEIG, P AF BERG, JM SATTELBERGER, AP MORRIS, DE VANDERSLUYS, WG FLEIG, P TI ION-PAIRING AND SOLVATION EFFECTS IN THE INTRA-5F2 ABSORPTION-SPECTRA OF DIMERIC URANIUM(IV) ALKOXIDE COMPLEXES SO INORGANIC CHEMISTRY LA English DT Article ID TETRAVALENT ACTINIDE IONS; INCOMMENSURATE THBR4; F-SHELL; U-4+; CHEMISTRY AB A spectroscopic study is presented of the [U2(OBu(t))9]- dimer anion in a series of structurally similar compounds, including a TBA+ salt reported and characterized here for the first time. Electronic absorption spectra are shown to reveal subtle manifestations of the influence of the coordination sphere on the metal-centered 5f2 manifold of electronic states. In crystalline KU2(OBu(t))9 each potassium is known to be closely associated with a single dimer anion. The spectra show this association to be maintained in nonaqueous solution. Weakening the association by increasing the size of the cation is shown to alter the f-f spectra by shifting bands to higher energy. Changing the solvent results in smaller shifts which are observable only at low temperature and are inferred to result from partial solvation of the cation. Quantitative trends in both the solvent-dependent and cation-dependent shifts are interpreted in terms of the influence of the environment on the electron repulsion within the 5f shell and on the crystal-field splitting of the free-ion states. C1 UNIV MONTANA,DEPT CHEM,MISSOULA,MT 59812. RP BERG, JM (reprint author), LOS ALAMOS NATL LAB,DIV ISOTOPE & NUCL CHEM,LOS ALAMOS,NM 87545, USA. RI Morris, David/A-8577-2012 NR 22 TC 9 Z9 9 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 MAR 3 PY 1993 VL 32 IS 5 BP 647 EP 653 DI 10.1021/ic00057a027 PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA KQ051 UT WOS:A1993KQ05100027 ER PT J AU CLARK, DL MILLER, MM WATKIN, JG AF CLARK, DL MILLER, MM WATKIN, JG TI SYNTHESIS, CHARACTERIZATION, AND X-RAY STRUCTURE OF THE URANIUM THIOLATE COMPLEX U(S-2,6-ME2C6H3)[N(SIME3)2]3 SO INORGANIC CHEMISTRY LA English DT Note ID HYDROGEN-DEUTERIUM EXCHANGE; CRYSTAL-STRUCTURE; DERIVATIVES; REACTIVITY; CHEMISTRY; ALKYL C1 COLORADO STATE UNIV,DEPT CHEM,FT COLLINS,CO 80523. RP CLARK, DL (reprint author), LOS ALAMOS NATL LAB,DIV ISOTOPE & NUCL CHEM,INORGAN & STRUCT CHEM GRP,LOS ALAMOS,NM 87545, USA. RI Clark, David/A-9729-2011 NR 26 TC 29 Z9 29 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 MAR 3 PY 1993 VL 32 IS 5 BP 772 EP 774 DI 10.1021/ic00057a044 PG 3 WC Chemistry, Inorganic & Nuclear SC Chemistry GA KQ051 UT WOS:A1993KQ05100044 ER PT J AU HOUGHTON, JC DOLTON, GL MAST, RF MASTERS, CD ROOT, DH AF HOUGHTON, JC DOLTON, GL MAST, RF MASTERS, CD ROOT, DH TI UNITED-STATES-GEOLOGICAL-SURVEY ESTIMATION PROCEDURE FOR ACCUMULATION SIZE DISTRIBUTIONS BY PLAY SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Article AB How much oil and gas remains to be discovered in the United States is an important question for petroleum geologists. This paper presents an overview of the methods used by the U.S. Geological Survey in its assessment by play of undiscovered resources of the onshore and state offshore areas of the United States. For the 1989 assessment, new estimation procedures were designed to aid the geologist in the assessment of the size distribution for the remaining population of undiscovered accumulations. This paper presents the details of that procedure and examples of its application for two oil plays in Wyoming and Montana: the Minnelusa play in the Powder River basin and the Basin- Margin Anticline play in the Bighorn basin. In the new procedure, a truncated shifted Pareto (TSP) distribution was fitted to the size data for the discovered accumulations, which were generally split into three sequential parts: the first, second, and last one-third of the accumulations discovered in each play. Parameters from the fitted curves describing size and shape of the discovered accumulations provided a reference model for use in estimating the size distribution of the undiscovered accumulations in a play. In a given play, these accumulation size distributions multiplied by the estimated distribution for the numbers of undiscovered accumulations produced the resource estimates. This method provides a simple, straightforward, and flexible means for the geologist to use statistics as an aid in estimating undiscovered resources. C1 US GEOL SURVEY,DENVER FED CTR,DENVER,CO 80225. US GEOL SURVEY,RESTON,VA 22092. RP HOUGHTON, JC (reprint author), US DOE,DIV ENVIRONM SCI,ER-74,GTN,WASHINGTON,DC 20585, USA. NR 0 TC 9 Z9 20 U1 0 U2 0 PU AMER ASSOC PETROLEUM GEOLOGIST PI TULSA PA 1444 S BOULDER AVE, PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1993 VL 77 IS 3 BP 454 EP 466 PG 13 WC Geosciences, Multidisciplinary SC Geology GA KQ550 UT WOS:A1993KQ55000007 ER PT J AU KUMAR, A SEGEV, A AF KUMAR, A SEGEV, A TI COST AND AVAILABILITY TRADEOFFS IN REPLICATED DATA CONCURRENCY-CONTROL SO ACM TRANSACTIONS ON DATABASE SYSTEMS LA English DT Article DE ALGORITHMS; PERFORMANCE; AVAILABILITY; REPLICATED DATABASE AB High availability of data is clearly a very important goal in a distributed system. Most previous studies have concentrated on the unconstrained maximization of availability, disregarding communications costs. Here we model this problem as one of minimizing communications costs subject to availability constraints. Two models for such constrained optimization are presented: The first characterizes availability deterministically, while the second one does so probabilistically. Other simpler models that are special cases of these two basic models and that arise from making simplifying assumptions such as equal vote values or constant intersite communications costs are also discussed. We describe a semi-exhaustive algorithm and efficient heuristics for solving each model. The algorithms utilize a novel signature-based method for identifying equivalent vote combinations, and an efficient procedure for computing availability. Computational results for the various algorithms are also given. C1 UNIV CALIF BERKELEY,WALTER A HASS SCH BUSINESS,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV INFORMAT & COMP SCI,BERKELEY,CA 94720. RP KUMAR, A (reprint author), CORNELL UNIV,GRAD SCH MANAGEMENT,ITHACA,NY 14853, USA. NR 18 TC 20 Z9 20 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 SN 0362-5915 J9 ACM T DATABASE SYST JI ACM Trans. Database Syst. PD MAR PY 1993 VL 18 IS 1 BP 102 EP 131 DI 10.1145/151284.151287 PG 30 WC Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA LD839 UT WOS:A1993LD83900003 ER PT J AU CODY, WJ AF CODY, WJ TI ALGORITHM-714 CELEFUNT - A PORTABLE TEST PACKAGE FOR COMPLEX ELEMENTARY-FUNCTIONS SO ACM TRANSACTIONS ON MATHEMATICAL SOFTWARE LA English DT Article DE ALGORITHMS; MEASUREMENT; PERFORMANCE; PERFORMANCE EVALUATION AB This paper discusses CELEFUNT, a package of Fortran programs for testing complex elementary functions. RP CODY, WJ (reprint author), ARGONNE NATL LAB,DIV MATH & COMP SCI,ARGONNE,IL 60439, USA. NR 6 TC 9 Z9 10 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 SN 0098-3500 J9 ACM T MATH SOFTWARE JI ACM Trans. Math. Softw. PD MAR PY 1993 VL 19 IS 1 BP 1 EP 21 DI 10.1145/151271.151272 PG 21 WC Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA LR434 UT WOS:A1993LR43400001 ER PT J AU CODY, WJ AF CODY, WJ TI ALGORITHM-715 - SPECFUN - A PORTABLE FORTRAN PACKAGE OF SPECIAL FUNCTION ROUTINES AND TEST DRIVERS SO ACM TRANSACTIONS ON MATHEMATICAL SOFTWARE LA English DT Article DE ALGORITHMS; BESSEL FUNCTIONS; ERROR FUNCTION; EXPONENTIAL INTEGRALS; GAMMA FUNCTION ID PERFORMANCE EVALUATION; BESSEL-FUNCTIONS; PROGRAMS AB SPECFUN is a package containing transportable FORTRAN special function programs for real arguments and accompanying test drivers. Components include Bessel functions, exponential integrals, error functions and related functions, and gamma functions and related functions. RP CODY, WJ (reprint author), ARGONNE NATL LAB,DIV MATH & COMP SCI,ARGONNE,IL 60439, USA. NR 25 TC 26 Z9 26 U1 0 U2 2 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 SN 0098-3500 J9 ACM T MATH SOFTWARE JI ACM Trans. Math. Softw. PD MAR PY 1993 VL 19 IS 1 BP 22 EP 32 DI 10.1145/151271.151273 PG 11 WC Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA LR434 UT WOS:A1993LR43400002 ER PT J AU WENDROFF, B AF WENDROFF, B TI AN ANALYSIS OF FRONT TRACKING FOR CHROMATOGRAPHY SO ACTA APPLICANDAE MATHEMATICAE LA English DT Article DE CHROMATOGRAPHY; HYPERBOLIC; FRONT TRACKING; RIEMANN PROBLEMS ID CONSERVATION-LAW AB We prove that front tracking has a convergent subsequence for the equations of chromatography for initial data with large variation. We show that this is also true for a variant of front tracking which tracks all waves. An example of a computation with the latter is presented. C1 LOS ALAMOS NATL LAB,DIV T,LOS ALAMOS,NM 87545. NR 18 TC 12 Z9 12 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0167-8019 J9 ACTA APPL MATH JI Acta Appl. Math. PD MAR PY 1993 VL 30 IS 3 BP 265 EP 285 DI 10.1007/BF00995472 PG 21 WC Mathematics, Applied SC Mathematics GA KU861 UT WOS:A1993KU86100002 ER PT J AU LONG, TW AF LONG, TW TI SATELLITE DESPINNING CONTROL IN THE EQUIVALENT AXIS FRAME SO ACTA ASTRONAUTICA LA English DT Article AB The nonlinear equations of motion for the despinning of a satellite can be transformed into linear equations by considering the motion in the equivalent axis frame. Within this frame despinning becomes a plane motion, resulting in only one linear equation of motion. This is a much simpler problem than using the three nonlinear Euler equations. The reduced computation requirement makes it possible to implement look-ahead control by computing a sequence of optimal control actions at every time stage. The look-ahead controller is potentially more stable than the horizon-of-one controllers. RP LONG, TW (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT ELECTR ENGN,L-463,LIVERMORE,CA 94551, USA. NR 0 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 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD MAR PY 1993 VL 29 IS 3 BP 153 EP 158 DI 10.1016/0094-5765(93)90044-W PG 6 WC Engineering, Aerospace SC Engineering GA KV274 UT WOS:A1993KV27400002 ER PT J AU SWEET, RM SINGER, PT SMALAS, A AF SWEET, RM SINGER, PT SMALAS, A TI CONSIDERATIONS IN THE CHOICE OF A WAVELENGTH RANGE FOR WHITE-BEAM LAUE DIFFRACTION SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID CRYSTALLOGRAPHY; PROTEIN AB The white-beam Laue-diffraction method is a useful tool for rapid measurement of crystallographic intensities with synchrotron radiation. Considerations of the signal-to-noise ratio to be expected from scattering of X-rays within a limited wavelength range suggest that it will pay to limit that range to something like an octave. This rule-of-thumb has the added advantage that there will be significantly fewer diffraction spots that are overlapping harmonics of one another. To maximize the number of reflections recorded in a single stationary-crystal exposure, one should choose this octave of wavelengths in a region where the curvature of the Ewald sphere is greatest, that is at the longest wavelength allowable after other considerations are taken into account. C1 ARGONNE NATL LAB,DEPT BIOL,ARGONNE,IL 60439. UNIV TROMSO,INST MATH & PHYS SCI,N-9000 TROMSO,NORWAY. RP SWEET, RM (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. RI Smalas, Arne/C-4131-2016 OI Smalas, Arne/0000-0002-4651-9911 NR 11 TC 8 Z9 10 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD MAR 1 PY 1993 VL 49 BP 305 EP 307 DI 10.1107/S0907444992012095 PN 2 PG 3 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA KY061 UT WOS:A1993KY06100008 PM 15299535 ER PT J AU RIBEIRO, MAMD AF RIBEIRO, MAMD TI TRANSMISSION AND SURVIVAL OF ACREMONIUM AND THE IMPLICATIONS FOR GRASS BREEDING SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT LA English DT Article; Proceedings Paper CT INTERNATIONAL SYMP ON ACREMONIUM-GRASS INTERACTIONS CY NOV 05-07, 1990 CL NEW ORLEANS, LA SP USDA ARS, USDA CRS, USDA, LOUISIANA AGR EXPT STN ID N-FORMYL LOLINE; TALL FESCUE; PERENNIAL RYEGRASS; FUNGAL ENDOPHYTE; EPICHLOE-TYPHINA; LEAF SHEATHS; SEED; ASSOCIATION; COENOPHIALUM; FESTUCA AB The transmission and survival of species of the endophyte fungi Acremonium in Festuca arundinacea Schreb. (Fa), Lolium perenne L. (Lp) and Lolium multiflorum Lam. (Lm) as well as in festulolium (Lp/Lm x Fa) hybrids are reviewed. As little work has been specifically conducted on the mode of transfer of the endophyte from the parents to the progeny, this matter is mainly discussed on the basis of research results at Oak Park. Progenies from more than 50 reciprocal intergeneric crosses of infected and non-infected parents were studied. The results confirmed that the transmission of infection was mainly dependent on the presence of endophytic mycelium in the female parent. It was also found that the content of perloline in the host had no effect on the growth of the endophyte. Microscopic observation of leaf sheaths stained with cotton-blue lactophenol confirmed that Acremonium hyphae in Fa, Lp, Lm and hybrids were very similar. However, the presence of pyrrolizidine alkaloids in hybrid festulolium plants from crosses in which Lm or Lp were the female parent suggests the possible existence of Acremonium coenophialum biotypes that infect hosts other than Fa. The study of progenies from 30 reciprocal sib-crosses revealed some discrepancies among results given by endophyte detection methods (microscopic observation of stained leaf sheaths, enzyme-linked immunosorbent assay and chemical) which demonstrate the limitations of exclusive use of the ELISA test for screening breeding material. The survival of Acremonium spp. in seed and plants in vivo is reviewed with special emphasis on the effects of environmental conditions. Finally, the viability of the endophyte in seeds of ecotypes and cultivars kept in long-term storage in gene banks is discussed in relation to the effects on seeds used in grass breeding programmes. RP RIBEIRO, MAMD (reprint author), TEAGASC,OAK PK RES CTR,CARLOW,IRELAND. NR 62 TC 9 Z9 9 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8809 J9 AGR ECOSYST ENVIRON JI Agric. Ecosyst. Environ. PD MAR PY 1993 VL 44 IS 1-4 BP 195 EP 213 PG 19 WC Agriculture, Multidisciplinary; Ecology; Environmental Sciences SC Agriculture; Environmental Sciences & Ecology GA KZ997 UT WOS:A1993KZ99700013 ER PT J AU LENCKA, M ANDERKO, A AF LENCKA, M ANDERKO, A TI MODELING PHASE-EQUILIBRIA IN MIXTURES CONTAINING HYDROGEN-FLUORIDE AND HALOCARBONS SO AICHE JOURNAL LA English DT Article ID STATE; EQUATION; VAPOR; ASSOCIATION C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. POLISH ACAD SCI,INST PHYS CHEM,KASPRZAKA 44152,PL-01224 WARSAW,POLAND. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. OI Anderko, Andrzej/0000-0002-1522-4889 NR 23 TC 26 Z9 26 U1 2 U2 3 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0001-1541 J9 AICHE J JI AICHE J. PD MAR PY 1993 VL 39 IS 3 BP 533 EP 537 DI 10.1002/aic.690390319 PG 5 WC Engineering, Chemical SC Engineering GA KQ325 UT WOS:A1993KQ32500018 ER PT J AU SPUHLER, JN AF SPUHLER, JN TI COEVOLUTION - GENES, CULTURE, AND HUMAN-DIVERSITY - DURHAM,WH SO AMERICAN ANTHROPOLOGIST LA English DT Book Review RP SPUHLER, JN (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544, USA. NR 1 TC 1 Z9 1 U1 1 U2 1 PU AMER ANTHROPOLOGICAL ASSOC PI ARLINGTON PA 4350 NORTH FAIRFAX DRIVE SUITE 640, ARLINGTON, VA 22203 SN 0002-7294 J9 AM ANTHROPOL JI Am. Anthropol. PD MAR PY 1993 VL 95 IS 1 BP 178 EP 179 DI 10.1525/aa.1993.95.1.02a00320 PG 2 WC Anthropology SC Anthropology GA KU108 UT WOS:A1993KU10800031 ER PT J AU SPINNER, NB LUCAS, JN POGGENSEE, M JACQUETTE, M SCHNEIDER, A AF SPINNER, NB LUCAS, JN POGGENSEE, M JACQUETTE, M SCHNEIDER, A TI DUPLICATION 9Q34-]QTER IDENTIFIED BY CHROMOSOME PAINTING SO AMERICAN JOURNAL OF MEDICAL GENETICS LA English DT Article DE DUP 9Q34; CHROMOSOME PAINTING; 12P+ ID PARTIAL TRISOMY 9Q; TRANSLOCATION; LIBRARIES; HYBRIDIZATION AB We have studied an infant with multiple anomalies and a 46,XY,12p + karyotype. Parental chromosomes were normal, and it was not possible to determine the identity of the extra material on chromosome 12 cytogenetically. Chromosome painting with probes from a chromosome 9 library identified this material as coming from chromosome 9, and cytogenetics established the duplication as 9q34-->qter. Comparison of this patient with others reported with partial dup(9q) documented excellent concordance of minor anomalies, most notably dolichocephaly, ''deep-set'' eyes, short horizontal palpebral fissures, beaked nose, micrognathia, arachnodactyly, and developmental delay. Identification of cytogenetically indeterminate abnormalities by molecular cytogenetics is very important, as it permits prognosis to be offered for families of newborn infants with unbalanced karyotypes. C1 ALBERT EINSTEIN MED CTR,NO DIV,DEPT PEDIAT,PHILADELPHIA,PA 19141. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA. BRYN MAWR HOSP,DEPT NEONATOL,BRYN MAWR,PA. NR 19 TC 20 Z9 20 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0148-7299 J9 AM J MED GENET JI Am. J. Med. Genet. PD MAR 1 PY 1993 VL 45 IS 5 BP 609 EP 613 DI 10.1002/ajmg.1320450519 PG 5 WC Genetics & Heredity SC Genetics & Heredity GA KM616 UT WOS:A1993KM61600018 PM 8456834 ER PT J AU MARKS, MP LANE, B STEINBERG, GK FABRIKANT, JI LEVY, RP FRANKEL, KA PHILLIPS, MH AF MARKS, MP LANE, B STEINBERG, GK FABRIKANT, JI LEVY, RP FRANKEL, KA PHILLIPS, MH TI ENDOVASCULAR TREATMENT OF CEREBRAL ARTERIOVENOUS-MALFORMATIONS FOLLOWING RADIOSURGERY SO AMERICAN JOURNAL OF NEURORADIOLOGY LA English DT Article DE ARTERIOVENOUS MALFORMATIONS, CEREBRAL; ARTERIOVENOUS MALFORMATIONS, EMBOLIZATION; INTERVENTIONAL NEURORADIOLOGY ID EMBOLIZATION; BRAIN; THERAPY; AVMS AB PURPOSE: Previous reports of embolization of cerebral arteriovenous malformations (AVMs) have evaluated the technique as an adjunctive therapy prior to surgery or radiosurgery; our aim is to assess the role of embolization following radiosurgery. PATIENTS: Six patients previously treated with radiosurgery and showing no response as judged by cerebral angiography were embolized 24 to 55 months (mean 34.3 months) after initial radiosurgery. RESULTS: In five of six, a significant volume reduction was achieved ranging from 60%-100% (mean 74%). One patient was treated with embolization alone and the AVM has remained fully thrombosed 2 years after treatment. Three patients underwent surgical resection for cure after embolization, and two patients had repeat radiosurgery to a significantly smaller AVM volume. One patient had an asymptomatic carotid dissection at embolization; however, no clinically apparent complications occurred in the treatment group. CONCLUSION: Embolization can be used after radiosurgery to assist in the management of those AVMs that have not responded to initial treatment. C1 STANFORD UNIV,MED CTR,SCH MED,DEPT DIAGNOST RADIOL,STANFORD,CA 94305. STANFORD UNIV,MED CTR,SCH MED,DEPT NEUROSURG,STANFORD,CA 94305. LAWRENCE BERKELEY LAB,DONNER PAVILION & DONNER LAB,BERKELEY,CA 94720. NR 22 TC 35 Z9 36 U1 0 U2 0 PU AMER SOC NEURORADIOLOGY PI OAK BROOK PA 2210 MIDWEST RD, OAK BROOK, IL 60521 SN 0195-6108 J9 AM J NEURORADIOL JI Am. J. Neuroradiol. PD MAR-APR PY 1993 VL 14 IS 2 BP 297 EP 303 PG 7 WC Clinical Neurology; Neuroimaging; Radiology, Nuclear Medicine & Medical Imaging SC Neurosciences & Neurology; Radiology, Nuclear Medicine & Medical Imaging GA KR570 UT WOS:A1993KR57000004 PM 8456702 ER PT J AU VOLKOW, ND WANG, GJ HITZEMANN, R FOWLER, JS WOLF, AP PAPPAS, N BIEGON, A DEWEY, SL AF VOLKOW, ND WANG, GJ HITZEMANN, R FOWLER, JS WOLF, AP PAPPAS, N BIEGON, A DEWEY, SL TI DECREASED CEREBRAL RESPONSE TO INHIBITORY NEUROTRANSMISSION IN ALCOHOLICS SO AMERICAN JOURNAL OF PSYCHIATRY LA English DT Article ID GAMMA-AMINOBUTYRIC ACID; SUBUNIT MESSENGER-RNAS; RAT-BRAIN; ETHANOL; INTOXICATION; SYNAPTONEUROSOMES; SENSITIVITY; ANTAGONIST; RO15-4513; DIAZEPAM AB Objective: Changes in gamma-aminobutyric acid (GABA)-benzodiazePine receptor function have been implicated in alcohol tolerance, withdrawal, and dependence. The purpose of this study was to investigate whether recently detoxified alcoholic subjects had abnormalities in brain GABA-benzodiazepine receptor function. Method: The effect of 30 mug/kg of lorazepam on regional brain glucose metabolism was studied in 12 normal subjects and 10 alcoholic subjects with the use of positron emission tomography and [F-18]fluorodeoxyglucose. Results: Lorazepam decreased whole brain glucose metabolism in both the normal subjects (13% change) and the alcoholic subjects (10% change), and the response was correlated with the concentration of lorazepam in plasma. Whereas the normal and alcoholic subjects showed similar responses to lorazepam in occipital and cerebellar metabolism, the alcoholic subjects showed significantly less of a response than the comparison subjects in the thalamus, basal ganglia, and orbitofrontal cortex. The rate of response in the orbitofrontal cortex was significantly correlated with cerebellar metabolism at baseline. Conclusions: The alcoholic subjects bad a blunted response to lorazepam that was specific to certain brain regions. The association between cerebellar metabolism and response to lorazepam suggests that the cerebellum may contribute to the decreased sensitivity to lorazepam which was seen in the alcoholic subjects. C1 BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. SUNY STONY BROOK,DEPT PSYCHIAT,STONY BROOK,NY 11794. VET ADM MED CTR,NORTHPORT,NY. RP VOLKOW, ND (reprint author), BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973, USA. FU NINDS NIH HHS [NS-15638] NR 35 TC 82 Z9 83 U1 0 U2 4 PU AMER PSYCHIATRIC ASSOCIATION PI WASHINGTON PA 1400 K ST NW, WASHINGTON, DC 20005 SN 0002-953X J9 AM J PSYCHIAT JI Am. J. Psychiat. PD MAR PY 1993 VL 150 IS 3 BP 417 EP 422 PG 6 WC Psychiatry SC Psychiatry GA KN845 UT WOS:A1993KN84500006 PM 8382010 ER PT J AU STEBBINS, JF BURNHAM, CW BISH, DL AF STEBBINS, JF BURNHAM, CW BISH, DL TI TETRAHEDRAL DISORDER IN FIBROLITIC SILLIMANITE - COMPARISON OF SI-29 NMR AND NEUTRON-DIFFRACTION DATA SO AMERICAN MINERALOGIST LA English DT Letter ID SILICATES AB In this paper Si-29 MAS NMR data for fibrolitic sillimanite from Pays de Leon, France, are presented that demonstrate that the sample has no significant Si-Al disorder within the double tetrahedral chains. This confirms previous findings of essentially complete short-range order in this mineral. However, a recently published neutron powder diffraction study of the same sample showed significant disorder (18%) among [4]Si and [4]Al. The only structure model that is consistent with both data sets is one of chain disorder, in which the relative positions of Si and Al from double chain to double chain are partially randomized without affecting the ordered Si-O-Al tetrahedral linkages. The entropic and energetic consequences of chain disorder are very small relative to those of normal random site disorder. C1 HARVARD UNIV,DEPT EARTH & PLANETARY SCI,CAMBRIDGE,MA 02138. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP STEBBINS, JF (reprint author), STANFORD UNIV,DEPT GEOL,STANFORD,CA 94305, USA. NR 8 TC 4 Z9 4 U1 1 U2 2 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1130 17TH ST NW SUITE 330, WASHINGTON, DC 20036 SN 0003-004X J9 AM MINERAL JI Am. Miner. PD MAR-APR PY 1993 VL 78 IS 3-4 BP 461 EP 464 PG 4 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA KY023 UT WOS:A1993KY02300026 ER PT J AU NARAYANAN, VA BEGUN, GM BELLO, JM STOKES, DL VO-DINH, T AF NARAYANAN, VA BEGUN, GM BELLO, JM STOKES, DL VO-DINH, T TI ANALYSIS OF THE PLANT-GROWTH REGULATOR ALAR (DAMINOZIDE) AND ITS HYDROLYSIS PRODUCTS USING RAMAN-SPECTROSCOPY SO ANALUSIS LA English DT Article ID P-AMINOBENZOIC ACID AB Normal Raman spectra (NRS), surface-enhanced Raman spectra (SERS), and Fourier transform(ed) Raman spectra (FTRS) of the important plant growth regulator Alar (daminozide; -succinic acid 2, 2-dimethylhydrazide, C6H12N2O3) were investigated and the comparative results are reponed in this work. The hydrolysis product of Alar, unsymmetrical dimethyl-hydrazine (UDMH) was studied via NRS, FTRS, SERS and the SERS of succinic acid was also recorded. A comparison of the spectral data of Alar with the data relating to the vibrational spectra of its hydrolysis products available in the literature and from the present studies is made and discussed. Tentative assignments for the observed vibrational frequencies of Alar are made. The enhancement of two peaks of succinic acid in the SERS spectra is presented. Features characteristic of the vibrational spectrum of UDMH which are distinct from the spectra of Alar and succinic acid are identified for reference purposes in studies dealing with the hydrolysis of Alar. C1 OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. NR 16 TC 14 Z9 14 U1 2 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0365-4877 J9 ANALUSIS JI Analusis PD MAR PY 1993 VL 21 IS 2 BP 107 EP 112 PG 6 WC Chemistry, Analytical SC Chemistry GA KQ284 UT WOS:A1993KQ28400019 ER PT J AU HEMBREE, DM SMYRL, NR DAVIS, WE WILLIAMS, DM AF HEMBREE, DM SMYRL, NR DAVIS, WE WILLIAMS, DM TI ISOMERIC CHARACTERIZATION OF POLYCHLORINATED-BIPHENYLS USING GAS-CHROMATOGRAPHY FOURIER-TRANSFORM INFRARED GAS-CHROMATOGRAPHY MASS-SPECTROMETRY SO ANALYST LA English DT Article DE POLYCHLORINATED BIPHENYL; GAS CHROMATOGRAPHY MASS SPECTROMETRY; GAS CHROMATOGRAPHY FOURIER TRANSFORM INFRARED SPECTROSCOPY; ISOMER IDENTIFICATION ID CONGENERS; PCB AB A new technique combining both mass spectrometry and infrared spectroscopy to analyse simultaneously the components from a single gas chromatographic injection has been applied to the quantitative and qualitative characterization (including distinguishing positional isomers) of polychlorinated biphenyl (PCB) mixtures. The sensitivity of vibrational spectroscopy to subtle differences in structure was shown to be highly complementary to gas chromatography-mass spectrometry (GC-MS) for qualitative identification of individual PCB isomers and congeners. A key feature of the infrared apparatus is the provision for low-temperature trapping (approximately 77 K) of the GC effluent for subsequent analysis. This technique produces infrared spectra that resemble normal room-temperature condensed-phase spectra (as opposed to the gas-phase spectra produced by light-pipe gas chromatography-Fourier transform infrared spectroscopy) and leads to lower detection limits (500 pg for 3,3',4,5-tetrachlorobiphenyl). The GC-MS portion of the instrument provides superior quantitative capabilities with sub-picogram detection limits possible using selective ion monitoring. RP HEMBREE, DM (reprint author), MARTIN MARIETTA ENERGY SYST INC,OAK RIDGE Y-12 PLANT,PLANT LAB,OAK RIDGE,TN 37831, USA. NR 13 TC 11 Z9 11 U1 0 U2 2 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 0003-2654 J9 ANALYST JI Analyst PD MAR PY 1993 VL 118 IS 3 BP 249 EP 251 DI 10.1039/an9931800249 PG 3 WC Chemistry, Analytical SC Chemistry GA KT044 UT WOS:A1993KT04400004 ER PT J AU HARPEL, MR LEE, EH HARTMAN, FC AF HARPEL, MR LEE, EH HARTMAN, FC TI ANION-EXCHANGE ANALYSIS OF RIBULOSE-BISPHOSPHATE CARBOXYLASE OXYGENASE REACTIONS - CO2/O2 SPECIFICITY DETERMINATION AND IDENTIFICATION OF SIDE PRODUCTS SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID RIBULOSE-1,5-BISPHOSPHATE CARBOXYLASE; RHODOSPIRILLUM-RUBRUM; SPECIES VARIATION; 1,5-BISPHOSPHATE; CATALYSIS; ASSAY RP HARPEL, MR (reprint author), OAK RIDGE NATL LAB,DIV BIOL,PROT ENGN PROGRAM,OAK RIDGE,TN 37831, USA. NR 36 TC 33 Z9 34 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 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD MAR PY 1993 VL 209 IS 2 BP 367 EP 374 DI 10.1006/abio.1993.1136 PG 8 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA KR444 UT WOS:A1993KR44400028 PM 8470812 ER PT J AU CHANG, HT YEUNG, ES AF CHANG, HT YEUNG, ES TI SELF-REGULATING DYNAMIC CONTROL OF ELECTROOSMOTIC FLOW IN CAPILLARY ELECTROPHORESIS SO ANALYTICAL CHEMISTRY LA English DT Letter ID EXTERNAL ELECTRIC-FIELD; ZONE ELECTROPHORESIS; CHROMATOGRAPHY; SEPARATION; SURFACTANT; ACID C1 US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RI Chang, Huan-Tsung/C-1183-2011; OI Chang, Huan-Tsung/0000-0002-5393-1410 NR 23 TC 23 Z9 23 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 1 PY 1993 VL 65 IS 5 BP 650 EP 652 DI 10.1021/ac00053a028 PG 3 WC Chemistry, Analytical SC Chemistry GA KN683 UT WOS:A1993KN68300029 ER PT J AU BUCHANAN, MV HETTICH, RL AF BUCHANAN, MV HETTICH, RL TI FOURIER-TRANSFORM MASS-SPECTROMETRY OF HIGH-MASS BIOMOLECULES SO ANALYTICAL CHEMISTRY LA English DT Article ID ULTRAVIOLET-LASER DESORPTION; SURFACE-INDUCED DISSOCIATION; CF-252 PLASMA DESORPTION; FAST ATOM BOMBARDMENT; ELECTROSPRAY IONIZATION; HIGH-RESOLUTION; LARGE MOLECULES; ION-SOURCE; PROTEINS; OLIGOPEPTIDES RP BUCHANAN, MV (reprint author), OAK RIDGE NATL LAB,DIV ANALYT CHEM,ORGAN SPECTROSCOPY GRP,OAK RIDGE,TN 37831, USA. RI Hettich, Robert/N-1458-2016; Buchanan, Michelle/J-1562-2016 OI Hettich, Robert/0000-0001-7708-786X; Buchanan, Michelle/0000-0002-8078-4575 NR 62 TC 102 Z9 104 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 1 PY 1993 VL 65 IS 5 BP A245 EP & DI 10.1021/ac00053a001 PG 0 WC Chemistry, Analytical SC Chemistry GA KN683 UT WOS:A1993KN68300002 PM 8452241 ER PT J AU WU, CL FENG, DH GUIDRY, MW AF WU, CL FENG, DH GUIDRY, MW TI NUCLEAR SUPERDEFORMATION AND THE SUPERSHELL FERMION DYNAMIC SYMMETRY MODEL SO ANNALS OF PHYSICS LA English DT Article ID POTENTIAL-ENERGY SURFACES; HIGH-SPIN; ROTATIONAL BANDS; HOLE EXCITATIONS; MASS REGION; STATES; ALIGNMENT; DY-152; SHAPES; ND-135 C1 JOINT INST HEAVY ION RES,OAK RIDGE,TN 37831. DREXEL UNIV,DEPT PHYS & ATMOSPHER SCI,PHILADELPHIA,PA 19104. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. RP WU, CL (reprint author), UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996, USA. NR 69 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 0003-4916 J9 ANN PHYS-NEW YORK JI Ann. Phys. PD MAR PY 1993 VL 222 IS 2 BP 187 EP 243 DI 10.1006/aphy.1993.1021 PG 57 WC Physics, Multidisciplinary SC Physics GA KX244 UT WOS:A1993KX24400002 ER PT J AU KATZEN, R HINMAN, ND AF KATZEN, R HINMAN, ND TI THERMAL, CHEMICAL, AND BIOLOGICAL PROCESSING - INTRODUCTION SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Editorial Material C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO. RP KATZEN, R (reprint author), RAPHAEL KATZEN ASSOCIATES INT INC,CINCINNATI,OH, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 3 EP 4 DI 10.1007/BF02918973 PG 2 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800002 ER PT J AU WYMAN, CE GOODMAN, BJ AF WYMAN, CE GOODMAN, BJ TI BIOTECHNOLOGY FOR PRODUCTION OF FUELS, CHEMICALS, AND MATERIALS FROM BIOMASS SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE ETHANOL; METHANE; BIODIESEL; CHEMICALS; BIOMASS ID ENZYMES AB Biological systems can convert renewable resources, including lignocellulosic biomass, starch crops, and carbon dioxide, into fuels, chemicals, and materials. Ethanol and other products are now derived from starch crops, such as corn. Enzyme-based technology is under development for conversion of lignocellulosic biomass (e.g., wood, grasses, and agricultural and municipal wastes) into fuel ethanol. The simultaneous saccharification and fermentation (SSF) process is employed to convert the cellulose fraction into ethanol at improved rates, higher yields, and higher ethanol concentrations than using sequential processing through careful selection of improved cellulase enzymes and fermentative microorganisms. Medium-BTU gas can be derived from lignocellulosic biomass by anaerobic digestion and cleaned up to a pipeline-quality gas. A high-solids fermenter achieves higher gas generation rates than conventional devices and promises to help make such gas economical. An extensive collection of more than 500 productive strains of microalgae has been established to produce lipid oils for diesel fuel and other compounds from carbon dioxide. Acetyl CoA carboxylase (ACC) has been shown to be a key enzyme in lipid oil synthesis, and genetic engineering approaches are being applied to enhance the rates and yields of product formation. In addition to fuels, a biorefinery could produce a wide range of chemicals and materials through microbial conversion of renewable resources, and technology is being developed for production of chemicals and materials from biomass. RP WYMAN, CE (reprint author), NATL RENEWABLE ENERGY LAB, DIV ALTERNAT FUELS, GOLDEN, CO 80401 USA. NR 40 TC 47 Z9 48 U1 0 U2 25 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 41 EP 59 DI 10.1007/BF02918976 PG 19 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800005 ER PT J AU TURHOLLOW, A KANHOUWA, S AF TURHOLLOW, A KANHOUWA, S TI FACTORS AFFECTING THE MARKET PENETRATION OF BIOMASS-DERIVED LIQUID TRANSPORTATION FUELS SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE BIOMASS; ETHANOL; REGULATIONS; MARKET PENETRATION; FUEL; CORN; ENERGY CROPS AB The market for liquid transportation fuels in the United States is about 610 x 10(9) L (160 x 10(9) gal) annually, with gasoline accounting for about 420 x 10(9) L (110 x 10(9) gal). Presently, about 3.4 x 10(9) L (0.9 x 10(9) gal) of ethanol are utilized in ethanol-gasoline blends. The barriers to greater use of ethanol in the transportation sector are economic as well as structural and institutional. Areas to consider are feedstock production, feedstock conversion to ethanol, fueling infrastructure, vehicle stocks, consumer acceptance, and regulations. Of these areas, regulation is probably the most important. C1 US DOE,ENERGY INFORMAT ADM,WASHINGTON,DC 20503. RP TURHOLLOW, A (reprint author), OAK RIDGE NATL LAB,BIOFUELS FEEDSTOCK DEV PROGRAM,OAK RIDGE,TN 37831, USA. NR 14 TC 0 Z9 0 U1 1 U2 1 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 61 EP 70 DI 10.1007/BF02918977 PG 10 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800006 ER PT J AU RIVARD, CJ AF RIVARD, CJ TI ANAEROBIC BIOCONVERSION OF MUNICIPAL SOLID-WASTES USING A NOVEL HIGH-SOLIDS REACTOR DESIGN - MAXIMUM ORGANIC LOADING RATE AND COMPARISON WITH LOW-SOLIDS REACTOR SYSTEMS SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article DE ANAEROBIC DIGESTION; MSW; HIGH SOLIDS; LOW SOLIDS; ORGANIC LOADING RATE ID DIGESTION; REQUIREMENTS; BIOGAS AB Novel, laboratory-scale, high-solids reactors operated under mesophilic conditions were used to study the anaerobic fermentation of processed municipal solid waste (MSW) to methane. Product gas rate data were determined for organic loading rates ranging from 2.99-18.46 g of volatile solids (VS) per liter (L) per day (d). The data represent the anaerobic fermentation at high-solids levels within the reactor of 21-32%, while feeding a refuse-derived fuel (RDF)/MSW feedstock supplemented with a vitamin/mineral/nutrient solution. The average biogas yield was 0.59 L biogas/g VS added to the reactor system/d. The average methane composition of the biogas produced was 57.2%. The data indicate a linear relationship of increasing total biogas production with increasing organic loading rate to the process. The maximum organic loading rate obtainable with high-solids anaerobic digestion is in the range of 18-20 g VS/L.d to obtain 80% or greater bioconversion for the RDF/MSW feedstock. This loading rate is approximately four to six times greater than that which can be obtained with comparable low-solids anaerobic bioreactor technology. RP RIVARD, CJ (reprint author), NATL RENEWABLE ENERGY LAB, DIV ALTERNAT FUELS, APPL BIOL SCI BRANCH, GOLDEN, CO 80401 USA. NR 35 TC 11 Z9 11 U1 0 U2 1 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 71 EP 82 DI 10.1007/BF02918978 PG 12 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800007 ER PT J AU RIVARD, CJ NAGLE, NJ ADNEY, WS HIMMEL, ME AF RIVARD, CJ NAGLE, NJ ADNEY, WS HIMMEL, ME TI ANAEROBIC BIOCONVERSION OF MUNICIPAL SOLID-WASTES - EFFECTS OF TOTAL SOLIDS LEVELS ON MICROBIAL NUMBERS AND HYDROLYTIC ENZYME-ACTIVITIES SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE ANAEROBIC DIGESTION; MSW; SOLIDS, HYDROLYTIC ENZYME, MICROBIAL NUMBERS ID DIGESTION; METHANE AB The anaerobic bioconversion of municipal solid wastes (MSW) produces both a valuable fuel product (methane) and a residue useful as a soil amendment. The application of high-solids fermentation technology offers improved economics over the more traditioinal low-solids fermentation systems. An important benefit of the high-solids process is the reduction in process water, which results in smaller fermentation reactors, and thus lower capital and operating costs. However, the anaerobic bioconversion process appears to be more efficient at high-solids as compared to low-solids levels. To understand the effects of solids levels on the anaerobic bioconversion process more thoroughly, representative high-solilds and low-solids anaerobic reactor systems processing identical MSW feedstocks are compared with respect to fermentation performance, total microbial cell number, and important hydrolytic enzyme activities. RP RIVARD, CJ (reprint author), NATL RENEWABLE ENERGY LAB,DIV ALTERNAT FUELS,APPL BIOL SCI BRANCH,GOLDEN,CO 80401, USA. NR 23 TC 10 Z9 10 U1 1 U2 2 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 107 EP 117 DI 10.1007/BF02918981 PG 11 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800010 ER PT J AU KIM, BJ LEE, YY TORGET, R AF KIM, BJ LEE, YY TORGET, R TI AN OPTIMAL TEMPERATURE POLICY OF PERCOLATION PROCESS AS APPLIED TO DILUTE-ACID HYDROLYSIS OF BIPHASIC HEMICELLULOSE SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Note ID XYLAN C1 AUBURN UNIV,DEPT CHEM ENGN,AUBURN,AL 36849. NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. NR 10 TC 15 Z9 15 U1 0 U2 2 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 119 EP 129 DI 10.1007/BF02918982 PG 11 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800011 ER PT J AU MATSUNAGA, T GREENBAUM, E AF MATSUNAGA, T GREENBAUM, E TI APPLIED BIOLOGICAL-RESEARCH .1. INTRODUCTION SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Editorial Material C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP MATSUNAGA, T (reprint author), TOKYO UNIV AGR & TECHNOL,FUCHU,TOKYO 183,JAPAN. NR 0 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 133 EP 133 DI 10.1007/BF02918983 PG 1 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800012 ER PT J AU HIMMEL, ME ADNEY, WS FOX, JW MITCHELL, DJ BAKER, JO AF HIMMEL, ME ADNEY, WS FOX, JW MITCHELL, DJ BAKER, JO TI ISOLATION AND CHARACTERIZATION OF 2 FORMS OF BETA-D-GLUCOSIDASE FROM ASPERGILLUS-NIGER SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE BETA-D-GLUCOSIDASES; ASPERGILLUS-NIGER; GLYCOPROTEINS; ENDOGLYCOSIDASE-H ID FUNGAL AB Beta-D-glucosidase purified from commercial preparations of clarified culture broth of Aspergillus niger (Novo SP188) was shown to elute as two distinct species during analytical anion-exchange chromatography (AEC). However, the two enzyme forms behaved identically on sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE), high-performance size-exclusion chromatography (HPSEC), and isoelectric focusing. Also, the N-terminal amino acid sequence, amino acid composition, fingerprint of tryptic-digest peptides, circular dichroism spectra, and reaction kinetics appear identical for these forms. This feature of the A. niger enzyme is distinctly different from beta-D-glucosidase isozyme's reported from other sources, where multiple forms tend to dfffer in molecular weight and/or isoelectric pH. Michaelis-Menten kinetic analysis also gave comparable results for the two forms. The distinct behavior on AEC was explained by considering the differences in N-linked carbohydrates liberated from both species following treatment with endoglycosidase H or F. C1 UNIV VIRGINIA, PROT & NUCLE ACID RES FACIL, CHARLOTTESVILLE, VA 22908 USA. RP HIMMEL, ME (reprint author), NATL RENEWABLE ENERGY LAB, DIV ALTERNAT FUELS, APPL BIOL SCI BRANCH, GOLDEN, CO 80401 USA. NR 24 TC 37 Z9 39 U1 1 U2 5 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 213 EP 225 DI 10.1007/BF02918991 PG 13 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800020 PM 8323261 ER PT J AU SCOTT, CD SCOTT, TC WOODWARD, CA AF SCOTT, CD SCOTT, TC WOODWARD, CA TI USE OF DINITROFLUOROBENZENE TO MODIFY ENZYMES FOR ENHANCED SOLUBILIZATION AND ACTIVITY IN ORGANIC-SOLVENTS SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Note ID BENZENE; LIPASE RP SCOTT, CD (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 22 TC 7 Z9 7 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 279 EP 287 DI 10.1007/BF02918996 PG 9 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800025 ER PT J AU WORDEN, RM RIVARD, CJ AF WORDEN, RM RIVARD, CJ TI APPLIED BIOLOGICAL-RESEARCH .2. INTRODUCTION SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Editorial Material C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO. RP WORDEN, RM (reprint author), MICHIGAN STATE UNIV,E LANSING,MI 48824, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 299 EP 299 DI 10.1007/BF02918998 PG 1 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800027 ER PT J AU TSAI, SP COLEMAN, RD MOON, SH SCHNEIDER, KA MILLARD, CS AF TSAI, SP COLEMAN, RD MOON, SH SCHNEIDER, KA MILLARD, CS TI STRAIN SCREENING AND DEVELOPMENT FOR INDUSTRIAL LACTIC-ACID FERMENTATION SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article DE LACTIC ACID; FERMENTATION; STRAIN DEVELOPMENT; STEREOSPECIFIC; PRODUCT INHIBITION ID CULTURES AB Thirty-four lactic acid bacterial strains have been screened for their potential in industrial lactic acid fermentations. The screening criteria included substrate utilization, product yield, resistance to product inhibition, product stereospecificity, growth temperature, fermentation rate, and ease of cell-broth separation. Acclimation techniques were also used to increase growth temperature and improve product tolerance. This effort has resulted in the identification and improvement of several promising strains, and a superior mixed culture. The mixed culture exhibited a >98% product stereospecificity, cell viability at 106.6 g/L lactic acid, and a productivity of 5.3 g/(L.h) in batch fermentation. RP TSAI, SP (reprint author), ARGONNE NATL LAB, 9700 S CASS AVE, ARGONNE, IL 60439 USA. NR 12 TC 14 Z9 15 U1 2 U2 4 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 EI 1559-0291 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 323 EP 335 DI 10.1007/BF02919000 PG 13 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800029 ER PT J AU LYND, LR GOODMAN, BJ AF LYND, LR GOODMAN, BJ TI BIOENGINEERING RESEARCH - INTRODUCTION SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Editorial Material C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO. RP LYND, LR (reprint author), DARTMOUTH COLL,HANOVER,NH 03755, USA. RI Lynd, Lee/N-1260-2013 OI Lynd, Lee/0000-0002-5642-668X NR 0 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 385 EP 385 DI 10.1007/BF02919004 PG 1 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800033 ER PT J AU DAVISON, BH THOMPSON, JE AF DAVISON, BH THOMPSON, JE TI CONTINUOUS DIRECT SOLVENT-EXTRACTION OF BUTANOL IN A FERMENTING FLUIDIZED-BED BIOREACTOR WITH IMMOBILIZED CLOSTRIDIUM-ACETOBUTYLICUM SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL ID ACETONE-BUTANOL; PRODUCT REMOVAL; ETHANOL-PRODUCTION; FERMENTATION; RECOVERY; DESIGN; CELLS AB Immobilized Clostridium acetobutylicum was used to ferment glucose into acetone and butanol in a fluidized-bed bioreactor. A nontoxic immiscible solvent, oleyl alcohol, was added to, and removed directly from, the fermenting columnar reactor and extracted the majority of the inhibitory butanol from the aqueous broth. The extracting solvent had a distribution coefficient of near 3 for butanol. Nonfermenting system tests indicated that equilibrium between the phases could be reached in one pass through the column. Steady-state results are presented for the fermentation with and without the extractive solvent addition. One run, with a continuous aqueous feedstream containing 40 g/L glucose, was operated for 23 d. A steady state was established with just the aqueous feedstream. Approximately half of the glucose was consumed, and the pH fell to 4.5 from 6.5. Then, during multiple intervals, the flow of organic extractive solvent (oleyl alcohol) was begun into the fermenting columnar reactor. A new apparent steady state was reached in about 4 h. The final aqueous butanol concentration was lowered by more than half. The total butanol production rate increased by 50-90% during the solvent extraction, as the organic-to-aqueous ratio increased from 1 to 4, respectively. There was an observed maximum volumetric productivity of 1.8 g butanol h-1L-1 in this nonoptimized system. The butanol yield apparently improved because of the removal of the inhibition. More substrate is going to the desired product, butanol, and less to maintenance or acid production, resulting in 10-20% increases in the ratio of butanol relative to all products. RP DAVISON, BH (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. RI Davison, Brian/D-7617-2013 OI Davison, Brian/0000-0002-7408-3609 NR 26 TC 34 Z9 36 U1 0 U2 7 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 415 EP 426 DI 10.1007/BF02919007 PG 12 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800036 ER PT J AU ANDREWS, GF STEVENS, CJ LEEPER, SA AF ANDREWS, GF STEVENS, CJ LEEPER, SA TI HEAPS AS BIOREACTORS FOR COAL BIOPROCESSING SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article DE COAL; PYRITIC SULFUR; BIOREACTORS; THIOBACILLUS AB The long time required for the microbial removal of pyritic sulfur from coal does not become an economic issue ff the coal is treated in heaps over which bacteria and nutrients are trickled. Correct heap design is dictated by the variation of the inherent process rate with coal particle size, the ability of water to trickle through heaps of fine coal without waterlogging owing to capillary forces, and the ability of oxygen and carbon dioxide to diffuse into the heap. A theoretical analysis of oxygen penetration combined with experimental measurements of water holdup suggests an optimum coal particle size in the range 6 x 30 mesh. This is confirmed by experiments on 4 in x 3 ft heaps of Illinois #6 coal ground to 30 x 100 and 12 x 30 mesh. The former plugs with biomass and ferric precipitates, whereas the latter shows good depyritization rate with minimal gradients through the heap. C1 ELI LILLY CO, CLINTON LABS, CLINTON, IN 47842 USA. RP ANDREWS, GF (reprint author), IDAHO NATL ENGN LAB, BIOTECH & ENVIRONM SCI GRP, POB 1625, IDAHO FALLS, ID 83415 USA. NR 10 TC 3 Z9 3 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 EI 1559-0291 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 427 EP 443 DI 10.1007/BF02919008 PG 17 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800037 ER PT J AU ASIF, M PETERSEN, JN SCOTT, TC COSGROVE, JM AF ASIF, M PETERSEN, JN SCOTT, TC COSGROVE, JM TI HYDRODYNAMIC STUDIES OF AN ADVANCED FLUIDIZED-BED BIOREACTOR FOR DIRECT COAL-LIQUEFACTION SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE FLUIDIZED BED; BIOPROCESSING; COAL; LIQUEFACTION ID SOLUBILIZATION; SEGREGATION; VERSICOLOR AB Advanced bioreactors can play an important role in coal utilization and conversion. To obtain the high throughput and low inventory required for large-scale bioprocessing of coal, a new family of bioreactors is being developed. The reactors on which this study is focused are continuous columnar bioreactors, which can be operated as three-phase systems. In particular, this study is oriented toward fluidized-bed systems for direct biological interactions with fine (30-150 mum) coal particles. Illinois no. 6 bituminous coal was ball-milled and then suspended in a 0.1% aqueous solution of the surfactant (Tween 80 (polyoxyethlene), which was used to reduce particle aggregation. Experimental fluidized-bed studies were then performed, using size-screened coal fractions. Studies were performed to quantify the extent of particle segregation and to quantify particle mixing effects within the reactor. To do so, pressure drop vs time data has been recorded as a function of axial position along the bed height. To better understand this experimental data, predictive mathematical models based on fundamental principles of mass and momentum transfer have been developed. Comparisons of model predictions with experimental data are presented. C1 WASHINGTON STATE UNIV,DEPT CHEM ENGN,PULLMAN,WA 99164. OAK RIDGE NATL LAB,CTR BIOPROC RES & DEV,OAK RIDGE,TN 37831. RI Petersen, James/B-8924-2008; Asif, Mohammad/C-6332-2009 OI Asif, Mohammad/0000-0003-3196-0074 NR 18 TC 5 Z9 5 U1 0 U2 1 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 535 EP 547 DI 10.1007/BF02919016 PG 13 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800045 ER PT J AU KLASSON, KT GUPTA, A CLAUSEN, EC GADDY, JL AF KLASSON, KT GUPTA, A CLAUSEN, EC GADDY, JL TI EVALUATION OF MASS-TRANSFER AND KINETIC-PARAMETERS FOR RHODOSPIRILLUM-RUBRUM IN A CONTINUOUS STIRRED-TANK REACTOR SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE RHODOSPIRILLUM-RUBRUM; CSTR; CARBON MONOXIDE; MASS TRANSFER; KINETICS AB The photosynthetic bacterium Rhodospirillum rubrum has been evaluated for its ability to produce hydrogen from carbon monoxide and water in a continuous stirred tank reactor according to the water-gas shift reaction. An assessment of mass-transfer parameters and reaction kinetics was made for this sparingly soluble substrate system. Experiments were conducted in a nonsteady-state fashion with continuous liquid and gas flow, which allowed for separation of the mass-transfer and kinetic-limited regions. Based on the data obtained, mass-transfer coefficients for the system were determined, and a mathematical expression for the reaction kinetics was formulated. The results showed that the hydrogen production was inhibited by elevated levels of dissolved carbon monoxide in the liquid. C1 UNIV ARKANSAS,DEPT CHEM ENGN,FAYETTEVILLE,AR 72701. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. OI Klasson, K. Thomas/0000-0003-3358-3081 NR 8 TC 14 Z9 14 U1 0 U2 3 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 549 EP 557 DI 10.1007/BF02919017 PG 9 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800046 ER PT J AU PHILLIPS, JR KLASSON, KT CLAUSEN, EC GADDY, JL AF PHILLIPS, JR KLASSON, KT CLAUSEN, EC GADDY, JL TI BIOLOGICAL PRODUCTION OF ETHANOL FROM COAL SYNTHESIS GAS - MEDIUM DEVELOPMENT STUDIES SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE C-LJUNGDAHLII; ETHANOL; ACETATE; SYNTHESIS GAS; CARBON MONOXIDE; HYDROGEN ID EUBACTERIUM-LIMOSUM; ENERGY-SOURCE AB The anaerobic bacteria Clostridium ljungdahlii produces ethanol and acetate from CO, CO2, and H-2 in synthesis gas. Early studies with the bacterium showed that relatively high concentrations of ethanol could be produced by lowering the fermentation pH and eliminating yeast extract from the medium in favor of a defined medium. This article presents the results from a medium development study based on the aerobic bacterium Escherichia coli. The results of continuous-reactor studies in a continuously stirred tank reactor (CSTR) with and without cell recycle are shown to demonstrate the utility of this improved medium. C1 UNIV ARKANSAS,DEPT CHEM ENGN,FAYETTEVILLE,AR 72701. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. OI Klasson, K. Thomas/0000-0003-3358-3081 NR 14 TC 58 Z9 66 U1 5 U2 32 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 559 EP 571 DI 10.1007/BF02919018 PG 13 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800047 ER PT J AU REEVES, M AF REEVES, M TI ENVIRONMENTAL BIOTECHNOLOGY - INTRODUCTION SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Editorial Material RP REEVES, M (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 619 EP 620 DI 10.1007/BF02919022 PG 2 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800051 ER PT J AU KORDE, VM PHELPS, TJ BIENKOWSKI, PR WHITE, DC AF KORDE, VM PHELPS, TJ BIENKOWSKI, PR WHITE, DC TI BIODEGRADATION OF CHLORINATED ALIPHATICS AND AROMATIC-COMPOUNDS IN TOTAL-RECYCLE EXPANDED-BED BIOFILM REACTORS SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE MIXED-WASTE BIODEGRADATION; BIOREACTORS; CHLORINATED ALIPHATICS; AROMATICS; BIOREMEDIATION ID TRICHLOROETHYLENE; DEGRADATION; BIOREACTORS; METHANE; SOIL AB Ground-water contamination by chlorinated aliphatic compounds is a major cause for concern because of their toxicity. This study examined the biodegradation of trichloroethylene and aromatic compounds by microbial consortia enriched from contaminated subsurface sediments. The consortia were capable of utilizing methane and propane as sources of carbon and energy. Two continuously recycled expanded-bed bioreactors were inoculated with (1) the subsurface consortium, and (2) P. fluorescence, P. putida (strains pRB1401 and pWWO), and M. trichosporium OB3b. An uninoculated reactor containing 0.2% sodium azide and 0.5% formalin served as the control. Methane (5% v/v) and propane (3% v/v) were maintained by batch feeding through the course of the experiment. Greater than 97% degradation of trichloroethylene was observed over a period of 12 d. More than 99% of benzene, toluene, and xylene were degraded within the first 7 d. Dissolved oxygen levels were measured and found to be in the range 4.9-6.5 mg/L throughout the experiments. C1 UNIV TENNESSEE,CTR ENVIRONM BIOTECHNOL,KNOXVILLE,TN 37932. UNIV TENNESSEE,DEPT CHEM ENGN,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. RI phelps, tommy/A-5244-2011 NR 23 TC 6 Z9 6 U1 3 U2 6 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 631 EP 641 DI 10.1007/BF02919024 PG 11 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800053 PM 8323267 ER PT J AU LACKEY, LW PHELPS, TJ BIENKOWSKI, PR WHITE, DC AF LACKEY, LW PHELPS, TJ BIENKOWSKI, PR WHITE, DC TI BIODEGRADATION OF CHLORINATED ALIPHATIC HYDROCARBON MIXTURES IN A SINGLE-PASS PACKED-BED REACTOR SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE MIXED-WASTE BIODEGRADATION; BIOREACTORS; CHLORINATED ALIPHATICS; AROMATICS; BIOREMEDIATION; BIODEGRADATION KINETICS ID TRICHLOROETHYLENE DEGRADATION; METHANOGENIC CONDITIONS; OXIDIZING BACTERIUM; ORGANIC-COMPOUNDS; TRANSFORMATIONS; METABOLISM; BIOTRANSFORMATION; BIOREACTORS; SOIL AB Aliphatic chlorinated compounds, such as trichloroethylene (TCE) and tetrachloroethylene (PCE), are major contaminants of ground water. A single-pass packed-bed bioreactor was utilized to study the biodegradation of organic waste mixtures consisting of PCE, TCE, and other short-chain chlorinated organics. The bioreactor consisted of two 1960-mL glass columns joined in a series. One column was packed with sand containing a microbial consortia enriched from a contaminated site. The other column provided a reservoir for oxygen and a carbon source of methane/propane that was recirculated through the reactor. Sampling was accomplished by both direct headspace and liquid effluent concentration analyses. The reactor was operated in a single-pass mode. Greater than 99% degradation of trichloroethylene, approaching drinking water standards, was observed when the bioreactor residence time ranged from 1.9 to 3.2 d. Typically, when the reactor was pulse-fed with methane, propane, and air, 1 mol of TCE was degraded/110 mol of substrate utilized. Perturbation studies were performed to characterize reactor behavior. The system's degradation behavior was affected by providing different carbon sources, a pulse feeding regime, supplementing microbial biomass, and by altering flow rates. C1 UNIV TENNESSEE,CTR ENVIRONM BIOTECHNOL,KNOXVILLE,TN 37996. UNIV TENNESSEE,DEPT MICROBIOL,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT CHEM ENGN,KNOXVILLE,TN 37996. RI phelps, tommy/A-5244-2011 NR 31 TC 14 Z9 14 U1 0 U2 3 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 701 EP 713 DI 10.1007/BF02919029 PG 13 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800058 PM 8323270 ER PT J AU BUMPUS, JA KAKAR, SN COLEMAN, RD AF BUMPUS, JA KAKAR, SN COLEMAN, RD TI FUNGAL DEGRADATION OF ORGANOPHOSPHOROUS INSECTICIDES SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE PHANEROCHAETE-CHRYSOSPORIUM; ORGANOPHOSPHOROUS INSECTICIDES; FUNGI; BIODEGRADATION ID WHITE ROT FUNGUS; PHANEROCHAETE-CHRYSOSPORIUM; DDT 1,1,1-TRICHLORO-2,2-BIS(4-CHLOROPHENYL)ETHANE; ENVIRONMENTAL-POLLUTANTS; BIODEGRADATION; SYSTEM AB Organophosphorous insecticides are used extensively in agriculture. As a group, they are easily degraded by bacteria in the environment. However, a number of them have half-lives of several months. Little is known about their biodegradation by fungi. We showed that Phanerochaete chrysosporium mineralized chlorpyrifos, fonofos, and terbufos (27.5, 12.2, and 26.6%, respectively) during an 18-d incubation in nutrient nitrogen-limited cultures. Results demonstrated that the chlorinated pyridinyl ring of chlorpyrifos and the phenyl ring of fonofos undergo cleavage during biodegradation by the fungus. The usefulness of P. chrysosporium for bioremediation is discussed. C1 ARGONNE NATL LAB, DIV BIOL & MED RES, ARGONNE, IL 60439 USA. UNIV NOTRE DAME, DEPT CHEM & BIOCHEM, NOTRE DAME, IN 46556 USA. RP BUMPUS, JA (reprint author), UNIV NOTRE DAME, CTR BIOENGN & POLLUT CONTROL, NOTRE DAME, IN 46556 USA. OI Bumpus, John/0000-0002-9222-7979 FU NIEHS NIH HHS [ES 04922] NR 16 TC 31 Z9 32 U1 0 U2 1 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 715 EP 726 DI 10.1007/BF02919030 PG 12 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800059 PM 7686734 ER PT J AU SHOUCHE, M PETERSEN, JN SKEEN, RS AF SHOUCHE, M PETERSEN, JN SKEEN, RS TI USE OF A MATHEMATICAL-MODEL FOR PREDICTION OF OPTIMUM FEEDING STRATEGIES FOR INSITU BIOREMEDIATION SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL DE INSITU BIOREMEDIATION; MATHEMATICAL MODEL; OPTIMIZATION; CARBON TETRACHLORIDE ID DENITRIFICATION CONDITIONS; CARBON-TETRACHLORIDE; ORGANIC-COMPOUNDS; TETRACHLOROMETHANE; TRANSFORMATIONS AB Liquid wastes containing radioactive, hazardous, and regulated chemicals have been generated throughout the 40+ years of operations at the US Department of Energy (DOE) Hanford site. Some of these wastes were discharged to the soil column, and many of the waste components, including nitrate, carbon tetrachloride (CCl4), and several radionuclides, have been detected in the Hanford ground water. Current DOE policy prohibits the disposal of the contaminated liquids directly to the environment, and remediation of the existing contaminated ground waters may be required. In situ bioremediation is one technology currently being developed at the Hanford to meet the need for cost-effective technologies to clean ground water contaminated with CCl4, nitrate, and other organic and inorganic contaminants. This article focuses on the latest results of an ongoing effort to develop effective in situ remediation strategies through the use of predictive simulations. In particular, strategies for nutrient injection are developed that minimize biomass accumulation within the flow field and thus extend the life of injection wells. C1 WASHINGTON STATE UNIV, DEPT CHEM ENGN, PULLMAN, WA 99164 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. RI Petersen, James/B-8924-2008 NR 17 TC 13 Z9 13 U1 0 U2 1 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 763 EP 779 DI 10.1007/BF02919034 PG 17 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800063 ER PT J AU ANTONOPOULOS, AA GROHMANN, K AF ANTONOPOULOS, AA GROHMANN, K TI RECENT RESEARCH EFFORTS IN THE AREA OF BIOTECHNOLOGY FOR FUELS AND CHEMICALS SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article; Proceedings Paper CT 14TH SYMP ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS CY MAY 11-15, 1992 CL GATLINBURG, TN SP US DOE, NATL RENEWABLE ENERGY LAB, BADGER ENGINEERS, NOVO NORDISK BIOIND, ARCHER DANIELS MIDLAND, MARTIN MARIETTA ENERGY SYST, MONSANTO CORP RES, SOUTH POINT ETHANOL, AMER CHEM SOC, DIV BIOCHEM TECHNOL C1 US CITRUS & SUBTROP PROD LAB,WINTER HAVEN,FL 33883. RP ANTONOPOULOS, AA (reprint author), ARGONNE NATL LAB,DIV ENVIRONM ASSESSMENT & INFORMAT SCI,ARGONNE,IL 60439, USA. NR 57 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP 793 EP 801 DI 10.1007/BF02919036 PG 9 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800065 ER PT J AU WOODWARD, J WYMAN, CE GOODMAN, BJ AF WOODWARD, J WYMAN, CE GOODMAN, BJ TI INTRODUCTION TO THE PROCEEDINGS OF THE 14TH SYMPOSIUM ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Editorial Material C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO. RP WOODWARD, J (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SPR PY 1993 VL 39 BP R3 EP R5 DI 10.1007/BF02918972 PG 3 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA LE638 UT WOS:A1993LE63800001 ER PT J AU FRITZ, IJ HAMMONS, BE HOWARD, AJ BRENNAN, TM OLSEN, JA AF FRITZ, IJ HAMMONS, BE HOWARD, AJ BRENNAN, TM OLSEN, JA TI FABRY-PEROT REFLECTANCE MODULATOR FOR 1.3 MU-M FROM (INALGA)AS MATERIALS GROWN AT LOW-TEMPERATURE SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; GAAS AB We report the first all-semiconductor Fabry-Perot-cavity reflectance modulators operating at wavelengths of 1.32-1.33 mum. These devices were grown on a GaAs substrate using an intermediate, linearly graded InGaAs buffer layer terminating in an In0.33Ga0.67As layer. The Bragg reflector stacks of the Fabry-Perot structure are composed of InGaAs and InAlAs layers lattice matched to the buffer, and the active cavity region is an In0.4Ga0.6As/In0.26Al0.35Ga0.39As strained-layer superlattice. The key to obtaining device-quality material was low temperature growth (approximately 400-degrees-C) of the entire structure. For a device with a 0.38-mum-thick active region and a 4 dB insertion loss, we obtained a contrast ratio of approximately 3:1 at 4 V bias. RP FRITZ, IJ (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 10 TC 25 Z9 25 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 MAR 1 PY 1993 VL 62 IS 9 BP 919 EP 921 DI 10.1063/1.108519 PG 3 WC Physics, Applied SC Physics GA KN944 UT WOS:A1993KN94400005 ER PT J AU XU, M AF XU, M TI APPROACH FOR MAGNETICALLY ESTIMATING TEMPERATURE-DEPENDENCE OF THE CRITICAL CURRENT-DENSITY SO APPLIED PHYSICS LETTERS LA English DT Article ID SUPERCONDUCTORS AB A method has been proposed to determine the critical current density (J(c)) from remanent magnetization measurements for type II superconductors. The method provides a consistent measurement of J(c) to Bean's original assumption in the critical state model. The temperature dependence of J(c) can be easily obtained from this method. As an example, the temperature dependence of J(c) in a single crystal of Bi2Sr2CaCu2Oy has been determined and discussed. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. RP XU, M (reprint author), US DOE,AMES LAB,AMES,IA 50011, USA. NR 7 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 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 1 PY 1993 VL 62 IS 9 BP 1014 EP 1016 DI 10.1063/1.109606 PG 3 WC Physics, Applied SC Physics GA KN944 UT WOS:A1993KN94400037 ER PT J AU KOLSKY, KL MAUSNER, LF AF KOLSKY, KL MAUSNER, LF TI PRODUCTION OF NO-CARRIER-ADDED AU-199 FOR GOLD CLUSTER-LABELED ANTIBODIES SO APPLIED RADIATION AND ISOTOPES LA English DT Article AB The production of no-carrier-added (NCA) Au-199 by neutron activation of Pt-198 was developed and the radiochemical separation of Au-199 from Pt targets was investigated. Three different procedures, based on anion exchange in mixed solvent media, solvent extraction and extraction chromatography, are reported. The extraction chromatography method was superior in terms of yield (>95%), Pt separation factor (less-than-or-equal-to 10(-5)), and separation time (approximately 1 hr). This scheme has been used to successfully process large amounts (> 30 GBq) of Au-199, with an average specific activity of 7.59 GBq/mug (205 mCi/mug). RP KOLSKY, KL (reprint author), BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973, USA. FU NCI NIH HHS [1U01CA51958-01] NR 24 TC 10 Z9 10 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD MAR PY 1993 VL 44 IS 3 BP 553 EP 560 DI 10.1016/0969-8043(93)90169-B PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA KQ756 UT WOS:A1993KQ75600014 PM 8472026 ER PT J AU GATLEY, SJ SHEA, CE AF GATLEY, SJ SHEA, CE TI TRAPPING AND DECOMPOSITION OF [F-18] FLUOROMETHANE, [C-11] FLUOROMETHANE AND OTHER GASEOUS HYDROFLUOROCARBONS ON ALUMINA AT ROOM-TEMPERATURE SO APPLIED RADIATION AND ISOTOPES LA English DT Article ID CEREBRAL BLOOD-FLOW; FLUOROMETHANE AB During a survey of adsorbents with potential utility in the preparation of the positron emission tomographic (PET) blood-flow tracer, [F-18]fluoromethane, irreversible binding to alumina was noted. No carrier added CH3[F-18] mixed with air was trapped (> 99.9%) on a 1.8 g alumina cartridge (Waters) at flow-rates as high as 50 mL/s. Trapped radioactivity could not be removed with air, water or acetonitrile, but was partially recovered as non-volatile F-18 in 1 N NaOH. With [C-11]fluoromethane, 96-99% of the C-11 was trapped, but 85% of the radioactivity was recovered in a 5 mL water rinse. On radio-HPLC (C18 column, 100% water) the eluted C-11 had the same retention time as [C-11]methanol. CH3[F-18] dissolved in water or acetonitrile was not hydrolyzed by alumina cartridges. Production of methanol from non-radio-active CH3F was confirmed by gas chromatography/mass spectroscopy. (CH3)2O) and in some experiments CH3Cl were also detected. CD3OH and (CD3)2O were similarly produced from CH3[F-18] of low specific activity. Unlabeled C2H5F yielded C2H5OH, (C2H5)2O and C2H5Cl. CF2HCH3 and (CH3)3SiF were also irreversibly trapped on alumina, but CF3H, CF4 and several other gases were not. The adsorption of CH3[F-18] on alumina may provide a useful and sensitive way of preventing and monitoring the escape of radioactive gas during PET imaging. RP GATLEY, SJ (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. NR 16 TC 0 Z9 0 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD MAR PY 1993 VL 44 IS 3 BP 587 EP 590 DI 10.1016/0969-8043(93)90174-9 PG 4 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA KQ756 UT WOS:A1993KQ75600019 ER PT J AU OSSANDON, JG THOMPSON, JR CHRISTEN, DK SUN, YR SALES, BC KERCHNER, HR TKACZYK, JE LAY, KW AF OSSANDON, JG THOMPSON, JR CHRISTEN, DK SUN, YR SALES, BC KERCHNER, HR TKACZYK, JE LAY, KW TI PROPERTIES OF ALIGNED YBA2CU3O7-DELTA SUPERCONDUCTOR AS A FUNCTION OF OXYGEN DEFICIENCY-DELTA SO APPLIED SUPERCONDUCTIVITY LA English DT Article ID FLUX-CREEP; GRAIN AB Systematic studies of flux pinning and intragrain critical current J(c) were conducted in magnetically aligned, sintered Y1Ba2Cu3O7-delta material as a function of oxygen deficiency delta in the range 0 approximately 0.2. The essential findings are: (1) maximum J(c) occurred at full oxygenation, i.e., J(c) and pinning decreased steadily as oxygen was removed; (2) the irreversibility line B(irr)(T,delta) was degraded with the introduction of oxygen defects; (3) this degradation was strongly correlated with the reduction of J(c)(delta), implying that the irreversibility line is determined by the strength of the flux pinning defects; (4) the condensation energy F(c) decreased significantly with delta, indicating a rapid weakening in the effectiveness of preexisting pinning centers; (5) both lambda and xi increased as oxygen was removed, while (6) their ratio K and the superconductive anisotropy parameter gamma = (lambda(c)/lambda(ab)) almost-equal-to 5 varied little for delta less-than-or-equal-to 0.2. C1 UNIV TENNESSEE, DEPT PHYS, KNOXVILLE, TN 37996 USA. OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. GE, CORP R & D LAB, SCHENECTADY, NY 12301 USA. RP OSSANDON, JG (reprint author), UNIV TALCA, FAC NAT RESOURCES, TALCA, CHILE. NR 19 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0964-1807 J9 APPL SUPERCOND JI Appl. Supercond. PD MAR-JUN PY 1993 VL 1 IS 3-6 BP 371 EP 380 DI 10.1016/0964-1807(93)90246-X PG 10 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA KT599 UT WOS:A1993KT59900024 ER PT J AU CHANG, HLM GAO, Y ZHANG, TJ LAM, DJ AF CHANG, HLM GAO, Y ZHANG, TJ LAM, DJ TI STRUCTURE AND PROPERTY OF HETEROEPITAXIAL TIO2/VO2 MULTILAYERS SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON SOLID FILMS AND SURFACES CY JUN 29-JUL 03, 1992 CL PARIS, FRANCE SP FRENCH MINIST RES & SPACE, CHAMBRE COMMERCE & IND PARIS, UNIV PIERRE & MARIE CURIE, CEA, CNRS, CTR NATL ETUDES TELECOMMUN, MARNE VALLEE VILLE NOUVELLE, THOMSON CSF, ST GOBAIN, APPLE ID GROWTH; FILMS AB Various types of TiO2/VO2 multilayer structures have been prepared on sapphire (1120BAR) substrates by a low-pressure metal-organic chemical vapor deposition process. X-ray diffraction and transmission electron microscopy techniques were used to study the crystallinity- and epitaxial relationships of the deposited films. High-resolution electron microscopy was used to examine the microstructure of the overlayers and interfaces. Electrical resistivity measurements were performed to investigate the metal-semiconductor phase transition of VO2 layers in multilayer structures. RP CHANG, HLM (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. NR 10 TC 6 Z9 6 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD MAR PY 1993 VL 65-6 BP 220 EP 226 DI 10.1016/0169-4332(93)90662-U PG 7 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA KW458 UT WOS:A1993KW45800038 ER PT J AU HILLS, JG GODA, MP AF HILLS, JG GODA, MP TI THE FRAGMENTATION OF SMALL ASTEROIDS IN THE ATMOSPHERE SO ASTRONOMICAL JOURNAL LA English DT Article AB The fragmentation of a small asteroid in the atmosphere greatly increases its cross-sections for aerodynamic braking and energy dissipation. The differential pressure across a meteoroid disperses its fragments at a velocity that increases with atmospheric density and impact velocity and decreases with meteoroid density. At a typical impact velocity of 22 km/s, the atmosphere absorbs more than half the kinetic energy of stony meteoroids with diameters, D(M) < 220 m and iron meteoroids with D(M) < 80 m. The corresponding diameter for comets with impact velocity 50 km/s is D(M) < 1600 m. Most of this energy dissipation occurs in a fraction of a scale height, which causes large meteoroids to appear to ''explode'' or ''flare'' at the end of their visible paths. The dissipation of energy in the atmosphere protects the Earth from direct impact damage (e.g., craters), but the blast wave produced by the dissipation in the atmosphere can cause considerable damage to structures on the ground. The area of destruction around the impact point in which the over pressure in the blast wave exceeds 4 pounds/inch2 = 2.8 X 10(5) dynes/cm3, which is enough to knock over trees and destroy buildings, increases rapidly from zero for chondritic meteoroids less than 56 m in diameter (15 megatons) to about 2000 square km for those 80 m in diameter (48 megatons). (The minimum diameter of the Tunguska impactor of 1908 is about 80 m.) The area of destruction produced by stony asteroids between 70 and 200 m in diameter is up to twice as great as it would be without fragmentation. Crater formation and earthquakes are not significant in land impacts by stony asteroids less than about 200 m in diameter because of the air protection. The situation is similar for the production of water waves and tsunami for ocean impacts. Tsunami is probably the most devastating type of damage for asteroids that are 200 m to 1 km in diameter. An impact by an asteroid this size anywhere in the Atlantic would devastate coastal areas on both sides of ocean. The atmosphere plume produced by asteroids with diameters exceeding about 120 m cannot be contained by the atmosphere, so this bubble of high-entropy gas forms a new layer on top of the atmosphere. The dust entrapped in this hot gas is likely to have optical depths exceeding tau = 10 for asteroids with diameters exceeding about 0.5-1 km. The optical flux from asteroids 60 m or more in diameter is enough to ignite pine forests. However, the blast wave from an impacting asteroid goes beyond the radius in which the fire starts. The blast wave tends to blow out the fire, so it is likely that the impact will char the forest (as at Tunguska), but the impact will not produce a sustained fire. Because comets dissipate their energy much higher in the atmosphere than asteroids, they illuminate a much larger region and their blast wave is weaker, so they are much more effective in producing large fires. This suggests that the Cretaceous-Tertiary impactor was a comet rather than an asteroid. RP HILLS, JG (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,THEORET ASTROPHYS GRP,MAIL STOP B288,LOS ALAMOS,NM 87545, USA. NR 23 TC 153 Z9 154 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAR PY 1993 VL 105 IS 3 BP 1114 EP 1144 DI 10.1086/116499 PG 31 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KQ553 UT WOS:A1993KQ55300030 ER PT J AU WOOSLEY, SE AF WOOSLEY, SE TI GAMMA-RAY BURSTS FROM STELLAR MASS ACCRETION DISKS AROUND BLACK-HOLES SO ASTROPHYSICAL JOURNAL LA English DT Article DE ACCRETION, ACCRETION DISKS; BLACK HOLE PHYSICS; GAMMA RAYS, BURSTS; STARS, EVOLUTION; SUPERNOVAE, GENERAL ID NEUTRON-STARS; SOLAR NEBULA; SUPERNOVA; APPEARANCE; EVOLUTION; WINDS AB A cosmological model for gamma-ray bursts is explored in which the radiation is produced as a broadly beamed pair fireball along the rotation axis of an accreting black hole. The black hole may be a consequence of neutron star merger or neutron star-black hole merger, but for long complex bursts, it is more likely to come from the collapse of a single Wolf-Rayet star endowed with rotation (''failed'' Type Ib supernova). The disk is geometrically thick and typically has a mass inside 100 km of several tenths of a solar mass. In the failed supernova case, the disk is fed for a longer period of time by the collapsing star. At its inner edge the disk is thick to its own neutrino emission and evolves on an viscous time scale of several seconds. In a region roughly 30 km across, interior to the accretion disk and along its axis of rotation, a pair fireball is generated by neutrino annihilation and electron-neutrino scattering which deposit approximately 10(50) ergs s-1. Electron scattering is more important in those cases where the baryonic contamination is high and the time scale for expansion increased. Extensive baryonic mass loss also occurs from the disk, and this may pose problems for production of a hard burst. Gamma-ray burst or not, this sort of event should occur in nature and should have an observable counterpart. C1 LAWRENCE LIVERMORE NATL LAB,DEPT PHYS,GEN STUDIES GRP,LIVERMORE,CA 94550. RP WOOSLEY, SE (reprint author), UNIV CALIF SANTA CRUZ,LICK OBSERV,BOARD STUDIES ASTRON & ASTROPHYS,SANTA CRUZ,CA 95064, USA. NR 43 TC 1526 Z9 1541 U1 8 U2 37 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 1993 VL 405 IS 1 BP 273 EP 277 DI 10.1086/172359 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KP297 UT WOS:A1993KP29700023 ER PT J AU ALEXANDREAS, DE ALLEN, G BERLEY, D BILLER, S BURMAN, RL CADY, DR CAVALLISFORZA, M CHANG, CY COYNE, D DION, C DION, GM DORFAN, D ELLSWORTH, RW FREEDMAN, SJ FUJIKAWA, BK GOODMAN, JA HAINES, TJ HOFFMAN, CM KELLEY, L KLEIN, S KRAKAUER, DA KWOK, PW LU, XQ NAGLE, DE POTTER, M SANDBERG, VD SINNIS, C SHOUP, A STARK, MJ VISHWANATH, PR WEEKS, DD WILLIAMS, DA WU, JP YODH, GB ZHANG, W AF ALEXANDREAS, DE ALLEN, G BERLEY, D BILLER, S BURMAN, RL CADY, DR CAVALLISFORZA, M CHANG, CY COYNE, D DION, C DION, GM DORFAN, D ELLSWORTH, RW FREEDMAN, SJ FUJIKAWA, BK GOODMAN, JA HAINES, TJ HOFFMAN, CM KELLEY, L KLEIN, S KRAKAUER, DA KWOK, PW LU, XQ NAGLE, DE POTTER, M SANDBERG, VD SINNIS, C SHOUP, A STARK, MJ VISHWANATH, PR WEEKS, DD WILLIAMS, DA WU, JP YODH, GB ZHANG, W TI DAILY SEARCH FOR EMISSION OF ULTRA HIGH-ENERGY RADIATION FROM POINT SOURCES SO ASTROPHYSICAL JOURNAL LA English DT Article DE GAMMA RAYS; OBSERVATIONS ID COSMIC-RAYS; CATALOG AB A daily search for emission of ultra-high-energy radiation from astrophysical point sources using the CYGNUS extensive air shower array is described. The data set spans the period from 1986 April 4 to 1992 June 22. Fifty-one astrophysical objects have been examined, including Cyg X-3, Her X-1, the Crab, a number of gamma-ray and X-ray sources from the COS B and the fourth Uhuru catalogs, and several cataclysmic variables, nearby galaxies, and radio pulsars. The observed daily number of events from the source directions are consistent with expected statistical fluctuations of the number of events from background cosmic rays. C1 UNIV MARYLAND,COLL PK,MD 20742. NATL SCI FDN,WASHINGTON,DC 20550. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. UNIV NOTRE DAME,NOTRE DAME,IN 46556. UNIV CALIF SANTA CRUZ,SANTA CRUZ,CA 95064. GEORGE MASON UNIV,FAIRFAX,VA 22030. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. ARGONNE NATL LAB,ARGONNE,IL 60439. TATA INST FUNDAMENTAL RES,BOMBAY 400005,INDIA. TATA INST FUNDAMENTAL RES,BOMBAY 400005,INDIA. UNIV NEW MEXICO,ALBUQUERQUE,NM 87131. UNIV CALIF RIVERSIDE,RIVERSIDE,CA 92521. RP ALEXANDREAS, DE (reprint author), UNIV CALIF IRVINE,IRVINE,CA 92717, USA. RI Cavalli-Sforza, Matteo/H-7102-2015 NR 23 TC 13 Z9 13 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 1993 VL 405 IS 1 BP 353 EP 358 DI 10.1086/172367 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KP297 UT WOS:A1993KP29700031 ER PT J AU TANG, IN MUNKELWITZ, HR AF TANG, IN MUNKELWITZ, HR TI COMPOSITION AND TEMPERATURE-DEPENDENCE OF THE DELIQUESCENCE PROPERTIES OF HYGROSCOPIC AEROSOLS SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE AEROSOL; DELIQUESCENCE; THERMODYNAMICS; TEMPERATURE DEPENDENCE; MIXED SALT ID REFRACTIVE-INDEX; WATER ACTIVITY; DENSITY AB Thermodynamic considerations are given to the hygroscopicity of inorganic salts comprising most of the ambient aerosols. Equations are derived expressing the deliquescence humidity as a function of composition and temperature for either single-salt or multicomponent aerosols. Experimental results obtained with charged salt particles individually suspended in an electrodynamic cell are compared both with theory and with available literature data on relative humidities over saturated aqueous solutions. The good agreement found between theory and experimental measurements indicates that aerosol deliquescence properties are predictable from the principle of solution thermodynamics. Furthermore, the experimental technique described here is ideally suited for providing data for complex aerosol systems about which no information is yet available. RP BROOKHAVEN NATL LAB, DIV ENVIRONM CHEM, UPTON, NY 11973 USA. NR 29 TC 279 Z9 284 U1 6 U2 81 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD MAR PY 1993 VL 27 IS 4 BP 467 EP 473 DI 10.1016/0960-1686(93)90204-C PG 7 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA KU201 UT WOS:A1993KU20100001 ER PT J AU GOODLETT, DR CAMP, DG HARDIN, CC CORREGAN, M SMITH, RD AF GOODLETT, DR CAMP, DG HARDIN, CC CORREGAN, M SMITH, RD TI DIRECT OBSERVATION OF A DNA QUADRUPLEX BY ELECTROSPRAY IONIZATION MASS-SPECTROMETRY SO BIOLOGICAL MASS SPECTROMETRY LA English DT Article ID CAPILLARY ZONE ELECTROPHORESIS; TELOMERIC DNA; INTERFACE; COMPLEXES AB In 10 mM sodium phosphate, pH 7.6, containing 0.1 mM ethylenediaminetetraacetic acid, ions corresponding to the non-covalent, four-stranded oligonucleotide, d(CGCG4GCG)4, were detected by negative ion electrospray ionization (ESI) mass spectrometry at a low nozzle-skimmer (DELTANS) bias (-150 V), but not at a higher DELTANS bias (> -250 V). In contrast, when the sample was desalted and analyzed by ESI mass spectrometry at a low DELTANS bias only ions for the single-stranded d(CGCG4GCG) species were observed. These data agree with spectroscopic evidence which showed that oligonucleotides with the sequence motif 5'd(CGCG(n)GCG)3', where n = 2-5, formed stable four-stranded complexes in the presence of monatomic cations, like K+, Ca2+, Na+ and Li+, but not in their absence. C1 PACIFIC NW LAB, DEPT CHEM SCI, RICHLAND, WA 99352 USA. EASTERN OREGON STATE COLL, BADGLEY HILL SCI, LA GRANDE, OR 97850 USA. N CAROLINA STATE UNIV, DEPT BIOCHEM, RALEIGH, NC 27695 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 FU NIGMS NIH HHS [GM45862-01] NR 30 TC 101 Z9 103 U1 0 U2 16 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 1052-9306 J9 BIOL MASS SPECTROM JI Biol. Mass Spectrom. PD MAR PY 1993 VL 22 IS 3 BP 181 EP 183 DI 10.1002/bms.1200220307 PG 3 WC Biophysics; Spectroscopy SC Biophysics; Spectroscopy GA KQ249 UT WOS:A1993KQ24900005 PM 8461341 ER PT J AU LEE, KD KANTOR, AB NIR, S OWICKI, JC AF LEE, KD KANTOR, AB NIR, S OWICKI, JC TI AGGREGATION OF HAPTEN-BEARING LIPOSOMES MEDIATED BY SPECIFIC ANTIBODIES SO BIOPHYSICAL JOURNAL LA English DT Article ID PHOSPHATIDYLSERINE-CONTAINING VESICLES; MASS-ACTION KINETICS; CELLULAR ULTRASTRUCTURE; ENVELOPED VIRUSES; FUSION; AGGLUTINATION; BINDING; PRECIPITATION; PRESERVATION; EQUILIBRIA AB We studied specific membrane-membrane interactions mediated by ligand-receptor binding in a model system which consisted of (a) FG3P, the fluorescein hapten attached to a phospholipid by a peptidyl spacer as described previously (Petrossian, A., A. B. Kantor, and J. C. Owicki. 1985. J. Lipid Res. 26:767-773), (b) antifluorescein monoclonal antibodies (MAbs), and (c) phospholipid vesicles (liposomes) into which the FG3P was incorporated. The aggregation of the hapten-bearing liposomes by four MAbs was studied by differential centrifugation. The ability of the MAbs to induce vesicle aggregation varied considerably and correlated inversely with affinity. Aggregation by one of the MAbs was studied in more detail by turbidimetry and freeze-fracture electron microscopy of samples frozen throughout the course of the aggregation. Rapid freezing was achieved with a double propane-jet apparatus. The aggregate morphologies and the time evolution of the aggregate size distribution were obtained from the two-dimensional fracture views with a stereological correction. The aggregation kinetics were simulated by considering dynamical aggregation according to a mass-action model with two parameters, the rate constants for antibody-mediated vesicle aggregation and disaggregation. Both rate constants were orders of magnitude lower than the rate constants for the corresponding interactions of antibodies with haptens either in solution or on vesicles under nonaggregating conditions. C1 UNIV CALIF BERKELEY,DEPT BIOPHYS & MED PHYS,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV CELL & MOLEC BIOL,BERKELEY,CA 94720. HEBREW UNIV JERUSALEM,FAC AGR,SEAGRAM CTR SOIL & WATER SCI,IL-76100 REHOVOT,ISRAEL. FU NIAID NIH HHS [AI-25534, AI-22860] NR 46 TC 12 Z9 12 U1 0 U2 1 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD MAR PY 1993 VL 64 IS 3 BP 905 EP 918 PG 14 WC Biophysics SC Biophysics GA KR826 UT WOS:A1993KR82600038 PM 8471733 ER PT J AU MCLAUGHLIN, SB TJOELKER, MG ROY, WK AF MCLAUGHLIN, SB TJOELKER, MG ROY, WK TI ACID DEPOSITION ALTERS RED SPRUCE PHYSIOLOGY - LABORATORY STUDIES SUPPORT FIELD OBSERVATIONS SO CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE LA English DT Article ID EASTERN-UNITED-STATES; SEASONAL PATTERNS; SMOKY MOUNTAINS; PICEA-RUBENS; 2 ELEVATIONS; FORESTS; SEEDLINGS; CALCIUM; RESPIRATION; SAPLINGS AB Two-year-old red spruce (Picea rubens Sarg.) seedlings were grown in a poorly buffered soil from a high-elevation site in the Great Smoky Mountains and exposed for 16 weeks to acid mist and rain chemically similar to that occurring at high-elevation sites in the southern Appalachian Mountains. Measurements of seedling growth, root distribution, saturated net photosynthesis, dark respiration, and nutrient content were made to test the hypothesis that acid deposition had caused reductions in the carbon economy noted at high-elevation sites in previous field studies. The role of base cation depletion in these changes was examined by evaluating soil amendments of Ca, Mg, or Ca plus Mg. Acidified rain and mist reduced (i) the apparent carbon economy of foliage, (ii) seedling growth, and (iii) rooting depth in these controlled greenhouse studies. Changes in gas exchange physiology paralleled responses observed for sapling trees in the field with increasing elevation and included both reduced net photosynthesis and increased dark respiration. Calcium deficiency induced by acid deposition is apparently an important mechanism underlying physiological responses of red spruce previously observed in the field. Calcium addition to soil partially reduced the effects of acid deposition, but observed responses suggest that both foliar- and soil-driven reactions are involved. Changes in carbon metabolism associated with reduced Ca availability, when high levels of acid deposition are superimposed on poorly buffered soils, support the inferential association of acid deposition with growth decline of mature red spruce in high-elevation forests of the Appalachian Mountains. RP MCLAUGHLIN, SB (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831, USA. RI Tjoelker, Mark/M-2413-2016 OI Tjoelker, Mark/0000-0003-4607-5238 NR 36 TC 44 Z9 45 U1 0 U2 8 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0045-5067 J9 CAN J FOREST RES JI Can. J. For. Res.-Rev. Can. Rech. For. PD MAR PY 1993 VL 23 IS 3 BP 380 EP 386 DI 10.1139/x93-055 PG 7 WC Forestry SC Forestry GA KV526 UT WOS:A1993KV52600007 ER PT J AU SMYTH, MJ WHARTON, W AF SMYTH, MJ WHARTON, W TI MULTIPARAMETER FLOW CYTOMETRIC ANALYSIS OF THE EFFECTS OF INDOMETHACIN ON ADIPOCYTE DIFFERENTIATION IN A31T6 CELLS SO CELL PROLIFERATION LA English DT Article ID INDUCTION AB A31T6 proadipocytes, derived from BALB/c-3T3 clone A31, develop responsiveness to differentiation-promoting agents at density-arrest and differentiate into adipocytes, as determined by the accumulation of cytoplasmic lipid droplets. A flow cytometric assay is being employed to monitor the acquisition of aspects of the differentiated phenotype. In this study, the assay is used to monitor both the rate of differentiation, as defined by the appearance of cells containing lipid droplets and the rate of adipocyte maturation, which involves measurement of increases in cytoplasmic lipid in cells already committed to the differentiation programme. Specifically, we show that 1 treatment with a combination of indomethacin and dexamethasone causes the maximum percentage differentiation in the population, 2 addition of indomethacin in combination with either dexamethasone or insulin increases the rate of differentiation, and 3 indomethacin selectively increases the maturation of adipocytes, measured as an increase in the amount of lipid per cell. The cytometric assay used in these experiments has allowed determination of the effects of indomethacin on aspects of the adipocyte phenotype that cannot be measured by standard techniques. RP SMYTH, MJ (reprint author), LOS ALAMOS NATL LAB,DIV LIFE SCI,CELLULAR & MOLEC BIOL GRP,LS-1,MAIL STOP M888,LOS ALAMOS,NM 87545, USA. FU NCRR NIH HHS [P41-RR01315] NR 19 TC 5 Z9 5 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0960-7722 J9 CELL PROLIFERAT JI Cell Prolif. PD MAR PY 1993 VL 26 IS 2 BP 103 EP 114 DI 10.1111/j.1365-2184.1993.tb00011.x PG 12 WC Cell Biology SC Cell Biology GA KX736 UT WOS:A1993KX73600001 PM 8471668 ER PT J AU LEIGH, CD SMITH, DM AF LEIGH, CD SMITH, DM TI A PIECEWISE-LINEAR APPROXIMATION TO DIFFUSION WITH NONLINEAR-INTERACTIONS - NONLINEAR SORPTION SO CHEMICAL ENGINEERING SCIENCE LA English DT Article ID ADSORPTION AB A solution for one-dimensional diffusion of a contaminant in a semi-infinite, porous slab is presented. The diffusion coefficient is constant, but sorption between the fluid and solid phase is nonlinear. Freundlich- and Langmuir-type isotherms are consider,d. The solution is based on a piecewise-linear approximation to the sorption isotherm. During transport, regions develop where analytical solutions corresponding to the linear segments of the isotherm can be used. The movement of the interfaces between these regions with time is tracked. 2-, 3-, 5-, and 10-region models were tested. The accuracy of the results was tested by comparing to a collocation solution using an L2 error analysis. L2 errors in all the cases were less than 3.1%. Accuracy generally improves as the number of regions used in the model is increased. In general, a 5-region model produces results with L2 error values less than 1%. The most important feature of the method, however, is that results are produced at a fraction of the computing cost. Central processing unit (CPU) times on a VAX 8650 computer for a 5-region, piecewise-linear model are, in general, five times smaller than the corresponding CPU time for the collocation technique. More importantly, the CPU time for the piecewise-linear solution is independent of the simulation time. The CPU time for the collocation solution increases with the total problem time because solutions are required at intermediate time steps. The piecewise-linear solution is strictly a function of the time and distance of interest. C1 UNIV NEW MEXICO,NSF,CTR MICROENGN CERAM,ALBUQUERQUE,NM 87131. SANDIA NATL LABS,DIV 6613,ALBUQUERQUE,NM 87185. NR 11 TC 2 Z9 2 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0009-2509 J9 CHEM ENG SCI JI Chem. Eng. Sci. PD MAR PY 1993 VL 48 IS 6 BP 1153 EP 1161 DI 10.1016/0009-2509(93)81043-U PG 9 WC Engineering, Chemical SC Engineering GA KL981 UT WOS:A1993KL98100013 ER PT J AU CHANTRANUPONG, L HIRSCH, G BUENKER, RJ DILLON, MA AF CHANTRANUPONG, L HIRSCH, G BUENKER, RJ DILLON, MA TI CONFIGURATION-INTERACTION CALCULATIONS OF THE VERTICAL ELECTRONIC-SPECTRUM OF SILANE SO CHEMICAL PHYSICS LA English DT Article ID PHOTOELECTRON-SPECTRA; PHOTOABSORPTION SPECTRA; MOLECULAR CALCULATIONS; VACUUM ULTRAVIOLET; EXCITED-STATES; BASIS SETS; ROW ATOMS; SIH4; SPECTROSCOPY; GERMANE AB Ab initio multireference single- and double-excitation configuration interaction (MRD-CI) calculations are reported for a large series of the lowest-lying electronic states of silane SiH4. The transition energies computed with and without the multi-reference Davidson correction are found to agree within 0.2 eV, which is an indication that the full CI level for the AO basis employed is approached to this degree of accuracy. These results are found to be in good agreement with the CIPSI values reported earlier by Larrieu et al., but lie as much as 1.0-1.5 eV above their Davidson-corrected MRSD-CI transition energies. On this basis it is argued that both the spectral peaks observed at 8.99 and 9.67 eV should be assigned as 2t2-->4s transitions, whereby the observed splitting is caused by a Jahn-Teller distortion of the upper 1T2 state. Optical f values are also reported, as well as computed singlet-triplet splittings. Finally the SiH4 dissociation process into SiH2 and H-2 products is also investigated. C1 ARGONNE NATL LAB,DIV ENVIRONM PHYS,ARGONNE,IL 60439. RP CHANTRANUPONG, L (reprint author), BERG UNIV GH WUPPERTAL,FACHBEREICH THEORET CHEM 9,GAUSSTR 20,W-5600 WUPPERTAL 1,GERMANY. NR 41 TC 20 Z9 20 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD MAR 1 PY 1993 VL 170 IS 2 BP 167 EP 175 DI 10.1016/0301-0104(93)80061-D PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KN809 UT WOS:A1993KN80900003 ER PT J AU KOSTIUK, LW BRAY, KNC CHENG, RK AF KOSTIUK, LW BRAY, KNC CHENG, RK TI EXPERIMENTAL-STUDY OF PREMIXED TURBULENT COMBUSTION IN OPPOSED STREAMS .1. NONREACTING FLOW FIELD SO COMBUSTION AND FLAME LA English DT Article ID COUNTERFLOWING STREAMS; FLAMES AB To provide a fundamental fluid mechanical background for a broader study of premixed turbulent combustion in opposed streams, this work examines the flow field in the absence of combustion. This particular flow geometry is part of a class of stagnating flows used to study fundamental turbulent combustion processes because the flow symmetry does not require any surface near the flames. The range of conditions studied-in terms of mean velocities, turbulent intensities and length scales-is similar to those where combustion could exist in the flow. Two-component laser doppler velocimetry is used to measure the velocity statistics. The mean flow is found to be self-similar for all the conditions tested, and produces a region of plane straining which is homogeneous in the vicinity of the stagnation. This self-similar flow structure is shown to include flows stagnated by a flat plate. There is a strong interaction between the existing turbulence in the flow and the mean straining which can increase the rms velocity as the flow stagnates. The mechanism that increases the turbulence is difficult to identify with certainty, but the results are found to be consistent with the ideas of vortex stretching. The turbulence in the flow is uniform across the jets and therefore any flame in the flow will experience the same upstream conditions over much of its area. C1 UNIV CAMBRIDGE,DEPT ENGN,CAMBRIDGE,ENGLAND. RP KOSTIUK, LW (reprint author), LAWRENCE BERKELEY LAB,B29C,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 31 TC 53 Z9 63 U1 1 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD MAR PY 1993 VL 92 IS 4 BP 377 EP 395 DI 10.1016/0010-2180(93)90150-2 PG 19 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA KM824 UT WOS:A1993KM82400003 ER PT J AU KOSTIUK, LW BRAY, KNC CHENG, RK AF KOSTIUK, LW BRAY, KNC CHENG, RK TI EXPERIMENTAL-STUDY OF PREMIXED TURBULENT COMBUSTION IN OPPOSED STREAMS .2. REACTING FLOW FIELD AND EXTINCTION SO COMBUSTION AND FLAME LA English DT Article ID COUNTERFLOWING STREAMS AB Turbulent combustion in opposed streams of premixed reactants was studied experimentally. In this geometry two flames are stabilized in the vicinity of the free stagnation point and separated by a region of products. In the mean the flames appear flat and perpendicular to the axis of the jets. Both the mean flow field and the distribution of the mean progress variable is found to be symmetric about the stagnation point. Buoyancy forces do not appear to affect the symmetry of the flow. The flows upstream of the flame zones has the same form of velocity field as nonreacting opposed flow, but displaced away from the stagnation point by the volume source due to combustion. Under certain conditions these flames can be forced to extinction, and this limit is studied for lean propane-air mixtures. This extinction depends only on the aerothermochemistry of the flow because there are no surfaces near the flames. For near extinct flames the flow field approaches that of nonreacting opposed streams. A physical mechanism is proposed for the extinction and results are compared with an extinction model. There is good qualitative agreement with the ''tinction model, and good quantitative agreement for the dependency of unstretched laminar burning velocity and the heat release parameter on extinction. C1 UNIV CAMBRIDGE,DEPT ENGN,CAMBRIDGE,ENGLAND. RP KOSTIUK, LW (reprint author), LAWRENCE BERKELEY LAB,B29C,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 27 TC 56 Z9 58 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD MAR PY 1993 VL 92 IS 4 BP 396 EP 409 DI 10.1016/0010-2180(93)90151-R PG 14 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA KM824 UT WOS:A1993KM82400004 ER PT J AU OSTROUCHOV, G FROME, EL AF OSTROUCHOV, G FROME, EL TI A MODEL SEARCH PROCEDURE FOR HIERARCHICAL-MODELS SO COMPUTATIONAL STATISTICS & DATA ANALYSIS LA English DT Article DE INFORMATION CRITERION; BAYES CRITERION; MODEL OPTIMALITY; PARTIAL ORDERING; COVER GRAPH; SPANNING TREE; DEPTH 1ST SEARCH; BRANCH AND BOUND ID REGRESSION-MODELS AB Large data sets cross-classified according to multiple factors are available in epidemiology and other disciplines. Their analysis often calls- for finding a small set of best hierarchical models to serve as a basis for further analysis. This selection can be based on some well defined model optimality criterion. Fitting all possible models to find a best set is usually not feasible for as few as five factors (7581 possible models). We note that the set of hierarchical models and their relationships can be represented by a graph and develop an algorithm to generate it efficiently. We further develop a graph traversal algorithm that requires fitting of only a fraction of all models to find exactly a best subset of the models. The algorithm classifies as many models as possible on the basis of each fit. A data structure implementing the graph of model nodes keeps track of the information required by the model search algorithm. C1 OAK RIDGE NATL LAB, MATH SCI SECT, OAK RIDGE, TN 37830 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9473 EI 1872-7352 J9 COMPUT STAT DATA AN JI Comput. Stat. Data Anal. PD MAR PY 1993 VL 15 IS 3 BP 285 EP 296 DI 10.1016/0167-9473(93)90257-T PG 12 WC Computer Science, Interdisciplinary Applications; Statistics & Probability SC Computer Science; Mathematics GA KP989 UT WOS:A1993KP98900002 ER PT J AU HAMSTRA, JR FINK, RL AF HAMSTRA, JR FINK, RL TI FFOL TRANSMISSION SERVICES - ISSUES FOR AN SMUX SO COMPUTER COMMUNICATIONS LA English DT Article DE FFOL; FDDI; SMUX; TRANSMISSION SERVICES AB The FDDI Follow-On LAN (FFOL) standard is being developed as a successor to FDDI. FFOL, like FDDI, consists of several standards, each a part of the whole. The lower three layers of FFOL standards provide the Transmission Services of FFOL. These are a Physical Layer Medium Dependent (PMD) standard, a Physical Layer Protocol (PHY) standard, and a Service Multiplexer (SMUX) standard. This paper discusses the issues affecting the development of the SMUX standard. These include the choice of FFOL payload multiplexing and payload encapsulation, and other SMUX functions required to support the other FFOL standards. A previous paper in this series on FFOL discussed the PHY component of Transmission Services; a future paper will discuss the PMD component. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP HAMSTRA, JR (reprint author), STANATEK,SHOREWOOD,MN, 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 0140-3664 J9 COMPUT COMMUN JI Comput. Commun. PD MAR PY 1993 VL 16 IS 3 BP 177 EP 183 DI 10.1016/0140-3664(93)90128-F PG 7 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA KM145 UT WOS:A1993KM14500005 ER PT J AU MEFFE, GK EHRLICH, AH EHRENFELD, D AF MEFFE, GK EHRLICH, AH EHRENFELD, D TI HUMAN-POPULATION CONTROL - THE MISSING AGENDA SO CONSERVATION BIOLOGY LA English DT Editorial Material RP MEFFE, GK (reprint author), UNIV GEORGIA,SAVANNAH RIVER ECOL LAB,DRAWER E,AIKEN,SC 29802, USA. NR 0 TC 28 Z9 28 U1 3 U2 8 PU BLACKWELL SCIENCE INC PI CAMBRIDGE PA 238 MAIN ST, CAMBRIDGE, MA 02142 SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD MAR PY 1993 VL 7 IS 1 BP 1 EP 3 DI 10.1046/j.1523-1739.1993.07010001.x PG 3 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA KR986 UT WOS:A1993KR98600001 ER PT J AU DUNN, CP STEARNS, F GUNTENSPERGEN, GR SHARPE, DM AF DUNN, CP STEARNS, F GUNTENSPERGEN, GR SHARPE, DM TI ECOLOGICAL BENEFITS OF THE CONSERVATION RESERVE PROGRAM SO CONSERVATION BIOLOGY LA English DT Article AB The Conservation Reserve Program was initiated in 1985 to reduce soil loss on highly erodible agricultural land. This stated objective of the program bas been quite successful. However, there are other unintentional yet significant ecological benefits to the program that merit evaluation. These benefits include the reversal of landscape fragmentation, maintenance of regional biodiversity, creation of wildlife habitat, and favorable changes in regional carbon flux. These and other benefits should be used by policy makers and federal officials to maintain the program even after enrollment expectations bave been achieved RP DUNN, CP (reprint author), ARGONNE NATL LAB,BLDG 900 EID,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 0 TC 52 Z9 56 U1 5 U2 15 PU BLACKWELL SCIENCE INC PI CAMBRIDGE PA 238 MAIN ST, CAMBRIDGE, MA 02142 SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD MAR PY 1993 VL 7 IS 1 BP 132 EP 139 DI 10.1046/j.1523-1739.1993.07010132.x PG 8 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA KR986 UT WOS:A1993KR98600019 ER PT J AU ISAACS, HS AF ISAACS, HS TI A STOCHASTIC-ANALYSIS OF POTENTIAL FLUCTUATIONS DURING PASSIVE FILM BREAKDOWN AND REPAIR OF IRON SO CORROSION SCIENCE LA English DT Note RP ISAACS, HS (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 6 TC 16 Z9 16 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0010-938X J9 CORROS SCI JI Corrosion Sci. PD MAR PY 1993 VL 34 IS 3 BP 525 EP 528 DI 10.1016/0010-938X(93)90121-V PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA KN708 UT WOS:A1993KN70800015 ER PT J AU FRIAR, JL AF FRIAR, JL TI 3-NUCLEON FORCES AND THE 3-NUCLEON SYSTEMS SO CZECHOSLOVAK JOURNAL OF PHYSICS LA English DT Article ID FADDEEV CALCULATIONS; LIGHT-NUCLEI; GROUND-STATE; ENERGY; SCATTERING; LAGRANGIANS AB The basic principles and philosophy which have guided the area of few-nucleon physics are motivated and discussed. Recent advances have made it possible to solve accurately the Schrodinger (or Faddeev) equation for many of the configurations of the few-nucleon systems. A brief review is given of some of the results of these calculations, which also indicate that one-pion exchange plays roughly the same role in binding these systems that it plays in electromagnetic meson-exchange currents. Finally, a qualitative discussion of chiral perturbation theory is presented, which highlights the role that chiral symmetry plays in the nuclear force. Three-body forces from different areas of physics are discussed, as well as the significance of three-nucleon forces in few-nucleon systems. C1 UNIV MAINZ,INST KERNPHYS,W-6500 MAINZ,GERMANY. RP FRIAR, JL (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 47 TC 17 Z9 17 U1 0 U2 0 PU CZECHOSLOVAK JNL OF PHYSICS PI PRAGUE PA FYZIKALNI USTAV AV NA SLOVANCE 2, PRAGUE, CZECH REPUBLIC 180 40 SN 0011-4626 J9 CZECH J PHYS JI Czech. J. Phys. PD MAR-APR PY 1993 VL 43 IS 3-4 BP 259 EP 287 DI 10.1007/BF01589847 PG 29 WC Physics, Multidisciplinary SC Physics GA LE415 UT WOS:A1993LE41500002 ER PT J AU GOLDSTEIN, SJ MURRELL, MT WILLIAMS, RW AF GOLDSTEIN, SJ MURRELL, MT WILLIAMS, RW TI PA-231 AND TH-230 CHRONOLOGY OF MIDOCEAN RIDGE BASALTS SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article ID EAST PACIFIC RISE; JUAN-DE-FUCA; GORDA RIDGES; HALF-LIFE; DISEQUILIBRIUM; MANTLE; SYSTEMATICS; U-238; MORB AB Mass spectrometric measurements of U-235-Pa-231 and U-238-Th-230 disequilibria are used to further constrain processes producing U-series disequilibria in young mid-ocean ridge basalts (MORB) and to determine eruption ages for samples from 9-10-degrees-N East Pacific Rise and Juan de Fuca-Gorda ridges. Pa-231/U-235 activity ratios for axial basalts are large and relatively uniform within ridge segments. The systematically large Pa-231/U-235, Th-230/U-238, and Ra-226/Th-230 activity ratios in MORB are inconsistent with simple equilibrium melting models and crustal contamination or seawater alteration processes. More complicated melting processes involving disequilibrium or heterogeneous melting of mantle sources and disequilibrium transport of melts to the crust could produce the large U-series disequilibria in MORB. Pa-231 and Th-230 model ages were determined by estimating initial Pa-231/U-235 and Th-230/Th-232 ratios from axial samples and by assuming constancy of these ratios over time. All Pa-231 and Th-230 ages agree to +/-0-7 ka for samples with ages of 0-130 ka. These concordant ages validate the model assumptions of the two dating methods and suggest that mantle sources and melt generation processes have been uniform for these areas during the past 130 ka. Consequently, Pa-231 and Th-230 age-dates can be used to quantify the temporal and spatial dependence of volcanism at oceanic spreading centers during the past 375 ka. C1 UNIV CALIF SANTA CRUZ,EARTH SCI BOARD,SANTA CRUZ,CA 95064. RP GOLDSTEIN, SJ (reprint author), LOS ALAMOS NATL LAB,MS K484,LOS ALAMOS,NM 87545, USA. RI Wright, Dawn/A-4518-2011 OI Wright, Dawn/0000-0002-2997-7611 NR 31 TC 74 Z9 77 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD MAR PY 1993 VL 115 IS 1-4 BP 151 EP 159 DI 10.1016/0012-821X(93)90219-Y PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KW193 UT WOS:A1993KW19300012 ER PT J AU HIGASHI, M PATTEN, BC BURNS, TP AF HIGASHI, M PATTEN, BC BURNS, TP TI NETWORK TROPHIC DYNAMICS - THE MODES OF ENERGY-UTILIZATION IN ECOSYSTEMS SO ECOLOGICAL MODELLING LA English DT Article ID FOOD-WEB; INDIRECT CAUSALITY; FLOW-ANALYSIS; CRITIQUE AB The concept of progressive efficiency is generalized from food chains to food networks of arbitrary structure. Two distinct modes and corresponding pathways of contribution to energy-matter utilization are identified and formulated using continuous time models of energy-matter flows in ecosystems. First passage or root utilization involves first time transfer and transformation (of assimilated substance only) along all direct and indirect food paths originating at a defined source compartment and terminating at a defined destination compartment. First passage paths include acyclic paths plus cyclic paths that do not pass through the destination compartments. Recycling or reutilization involves the subsequent retransformation of previously utilized but not dissipated energy-matter by consumers. Recycling pathways start and end at the defined destination compartment. Total or ultimate utilization by destination compartments is the sum of first passage and recycling utilization. Two properties of ecosystems are demonstrated which depart from those of conventional trophic dynamics. Network virtual amplification is the increase of energy-matter ultimately utilized at destination compartments compared to the quantities originally introduced at source compartments. This is due largely to recycling; no energy is created, no thermodynamic law violated. Network homogenization is the tendency in food cycles for introduced energy-matter to become more or less evenly distributed to all compartments. These properties are illustrated with two models of ecosystem energy-matter flows. C1 OAK RIDGE NATL LAB,DIV ENVIRONM SCI,SAIC,POB 2501,OAK RIDGE,TN 37831. RYUKOKU UNIV,FAC SCI & TECHNOL,OTSU 52021,JAPAN. UNIV GEORGIA,DEPT ZOOL,ATHENS,GA 30602. UNIV GEORGIA,INST ECOL,ATHENS,GA 30602. NR 48 TC 31 Z9 33 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3800 J9 ECOL MODEL JI Ecol. Model. PD MAR PY 1993 VL 66 IS 1-2 BP 1 EP 42 DI 10.1016/0304-3800(93)90037-S PG 42 WC Ecology SC Environmental Sciences & Ecology GA KP447 UT WOS:A1993KP44700001 ER PT J AU HIGASHI, M BURNS, TP PATTEN, BC AF HIGASHI, M BURNS, TP PATTEN, BC TI NETWORK TROPHIC DYNAMICS - THE TEMPO OF ENERGY MOVEMENT AND AVAILABILITY IN ECOSYSTEMS SO ECOLOGICAL MODELLING LA English DT Article ID FLOW AB Energy moves with varying temporality in ecosystems, and as a result becomes unevenly aged. This paper examines the time dependency of energy-matter flux in ecosystems modeled as flow-storage networks. The temporality of passage is governed by storage, which can be viewed as transport delay, a process contributing to the availability of energy to ecosystem compartments over time. Availability is a prior condition for utilization, which nevertheless is measurable from flow considerations alone. Combined flow-storage analyses are required to determine the temporality of substance availability; flow-only analyses are sufficient to specify utilization. The relations between the two are developed. What we term ''tempo'' involves the transport and delay as standing stocks of variously aged substance over the direct and indirect pathways of ecosystem networks. Our concept of ''mode'' refers to utilization alone, without regard for timing or the age distribution of flowing substance. Temporal analysis highlights the importance of turnover time, and thus body size and mass of individual organisms, in the dynamics of energy dependencies in ecosystems. C1 RYUKOKU UNIV,FAC SCI & TECHNOL,OTSU,JAPAN. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. UNIV GEORGIA,DEPT ZOOL,ATHENS,GA 30602. UNIV GEORGIA,INST ECOL,ATHENS,GA 30602. NR 22 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3800 J9 ECOL MODEL JI Ecol. Model. PD MAR PY 1993 VL 66 IS 1-2 BP 43 EP 64 DI 10.1016/0304-3800(93)90038-T PG 22 WC Ecology SC Environmental Sciences & Ecology GA KP447 UT WOS:A1993KP44700002 ER PT J AU KELLY, EJ KENNEDY, PL AF KELLY, EJ KENNEDY, PL TI A DYNAMIC STATE VARIABLE MODEL OF MATE DESERTION IN COOPER HAWKS SO ECOLOGY LA English DT Article DE ACCIPITER-COOPERII; COOPER HAWK; DYNAMIC STATE VARIABLE MODEL; MATE DESERTION; PARENTAL INVESTMENT; SENSITIVITY ANALYSIS ID PARENTAL CARE; SNAIL KITE; ACCIPITER-NISUS; EVOLUTION; SELECTION; SIZE; SPARROWHAWKS; STRATEGIES; INVESTMENT; MAMMALS AB In a 4-yr study of the reproductive strategies of Cooper's Hawks (Accipiter cooperii) nesting in north-central New Mexico, >50% of the females deserted during the fledgling-dependency period and did not renest. A dynamic state variable model was developed to study the females' brood-rearing strategies. In this model a strategy consisted of combinations of staying at the nest, hunting, and deserting. The modeling assumptions were: a female's strategy during brood rearing maximizes her reproductive fitness, defined as the weighted average of the expected probability of survival of her current offspring and her expected future reproduction; and the reproductive fitness function depends on the physical condition of the female and nestlings, the risks to the nestlings associated with each strategy, and the male's foraging capabilities. The model predictions were compared to the observations of female strategies in this population of Cooper's Hawks. To insure a valid comparison, the model parameters were estimated from sources other than the observed population. The best match between observations and predictions (84-96%) was obtained when the nestlings' survival and the female's future reproductive potential were equally weighted during the nestling stage, but weighted in favor of the female's reproductive potential during the fledgling stage. A sensitivity analysis showed that the model predictions corresponded well with the observations of staying and hunting at all parameter bounds. However, those combinations of parameter values that reflected conditions with the least pressure to desert missed 70-85% of the desertions. The sensitivity analysis also indicated that a key factor influencing the female's choice of strategy was the interaction between the threat to her future reproduction due to her poor physical condition and the nestlings' risk of death from predation and exposure. The agreement of model predictions and observed strategies supported the modeling assumptions. These results combined with the sensitivity analysis indicated that dynamic state variable modeling is an excellent tool for studying mate desertion. C1 LOS ALAMOS NATL LAB,ENVIRONM RESTORAT GRP,LOS ALAMOS,NM 87545. UTAH STATE UNIV,DEPT BIOL,LOGAN,UT 84322. RI Kennedy, Patricia/I-4902-2015 OI Kennedy, Patricia/0000-0002-2090-1821 NR 54 TC 30 Z9 31 U1 0 U2 12 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 SN 0012-9658 J9 ECOLOGY JI Ecology PD MAR PY 1993 VL 74 IS 2 BP 351 EP 366 DI 10.2307/1939298 PG 16 WC Ecology SC Environmental Sciences & Ecology GA KN556 UT WOS:A1993KN55600007 ER PT J AU JASTROW, JD MILLER, RM AF JASTROW, JD MILLER, RM TI NEIGHBOR INFLUENCES ON ROOT MORPHOLOGY AND MYCORRHIZAL FUNGUS COLONIZATION IN TALLGRASS PRAIRIE PLANTS SO ECOLOGY LA English DT Article DE ANDROPOGON; BELOWGROUND INTERACTIONS; COMPETITION; COREOPSIS; MYCORRHIZAL FUNGUS COLONIZATION; NEIGHBOR INTERACTIONS; RESTORATION; ROOT BRANCHING; ROOT MORPHOLOGY; ROOT RADIUS; SOLIDAGO; SPECIFIC ROOT LENGTH; TALLGRASS PRAIRIE ID VESICULAR-ARBUSCULAR MYCORRHIZA; SURFACE MICROORGANISMS; SOIL; INFECTION; SYSTEMS; SIZE; ENDOMYCORRHIZAS; COMPETITION; PHOSPHORUS; VEGETATION AB A field study was conducted across a chronosequence of tallgrass prairie restorations to investigate the influence a plant's neighbor may have on its gross root morphology and association with mycorrhizal fungi. The root systems of a warm-season grass, Andropogon gerardii, and two perennial forbs, Coreopsis tripteris and Solidago altissima, were sampled by excavating soil blocks representing all pairwise inter- and intra-specific combinations of these species. With forb neighbors, Andropogon had higher percentages of its fibrous roots colonized by mycorrhizal fungi than with conspecific neighbors. Andropogon root morphology (as measured by average root radius, specific root length, and root branching) did not vary with neighbor growth form; however, Andropogon roots did become finer as restoration age and root densities increased. For Coreopsis and Solidago, colonization of fibrous roots did not vary with neighbor species, but both forbs had coarser roots with interspecific neighbors than with conspecifics. With interspecific neighbors, Coreopsis almost doubled the number of branches per centimetre of root observed in conspecific pairs. Although some of the variations in colonization and root morphology may be attributable specifically to neighbor root mass, others were related to the overall root mass of the target-neighbor pair. The observed variations in mycorrhizal colonization may be related to increased opportunities for colonization by the fungus that are due not only to higher root densities but also to some sort of interaction between the root systems of Andropogon and the forbs. C1 UNIV ILLINOIS,DEPT BIOL SCI,CHICAGO,IL 60680. RP JASTROW, JD (reprint author), ARGONNE NATL LAB,DIV ENVIRONM RES,ARGONNE,IL 60439, USA. NR 44 TC 23 Z9 29 U1 3 U2 19 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 SN 0012-9658 J9 ECOLOGY JI Ecology PD MAR PY 1993 VL 74 IS 2 BP 561 EP 569 DI 10.2307/1939316 PG 9 WC Ecology SC Environmental Sciences & Ecology GA KN556 UT WOS:A1993KN55600025 ER PT J AU DONNELLYNOLAN, JM BURNS, MG GOFF, FE PETERS, EK THOMPSON, JM AF DONNELLYNOLAN, JM BURNS, MG GOFF, FE PETERS, EK THOMPSON, JM TI THE GEYSERS-CLEAR LAKE AREA, CALIFORNIA - THERMAL WATERS, MINERALIZATION, VOLCANISM, AND GEOTHERMAL POTENTIAL SO ECONOMIC GEOLOGY AND THE BULLETIN OF THE SOCIETY OF ECONOMIC GEOLOGISTS LA English DT Article ID COAST-RANGES; SEDIMENTATION; TECTONICS; SYSTEMS AB Manifestations of a major thermal anomaly in the Geysers-Clear Lake area of northern California include the late Pliocene to Holocene Clear Lake Volcanics, The Geysers geothermal field, abundant thermal springs, and epithermal mercury and gold mineralization. The epithermal mineralization and thermal springs typically occur along high-angle faults within the broad San Andreas transform fault system that forms the western boundary of the North American plate in this area. The young volcanic rocks overlie Mesozoic marine rocks of the Great Valley sequence which have been thrust above the coeval Franciscan Complex and penecontemporaneously dropped back down along low-angle detachment faults. Many of the waters of the region are nonmeteoric as defined by their isotopic signature. One type of isotopically shifted water emerges from or near Great Valley sequence rocks and is the most chloride rich. It is interpreted to be evolved connate in origin. A second type, evolved meteoric water, has moderate chloride contents, high boron contents, and high B/Cl ratios and is found locally in Franciscan rocks, notably at the Sulphur Bank mercury mine, where it probably results from near-closed-system, repeated boiling of meteoric water in host rocks that also contribute organic components to the water. At the Sulphur Bank mine fracturing of otherwise impermeable Franciscan rocks by faulting has created a localized zone of permeability in which thermal water boils repeatedly with limited venting to the surface. Boron-rich fluids were apparently present at depth in The Geysers geothermal field when intrusion of silicic magma occurred, because the concealed intrusion of felsite is surrounded by a halo of tourmaline-bearing hornfels. The volume of this poorly dated early to middle Quaternary intrusive body probably exceeds the 100 km3 of erupted Clear Lake Volcanics. Similar intrusions may have occurred in the eastern part of the area at Wilbur Springs and the McLaughlin mine, where gold deposition and evidence of hydrothermal phenomena suggest more magmatic activity than is indicated by the small exposed bodies of early Quaternary basaltic lava. The Clear Lake Volcanics are the present locus of volcanism in the northern Coast Ranges and progressively older volcanic centers occur to the south. Geophysical data suggest that a large silicic magma body may be centered north of The Geysers steam field, providing the heat for the geothermal field. Geothermal power production has peaked at The Geysers and pressure declines indicate significant depletion of the fluid resource. The vapor-dominated field evolved from a preexisting hydrothermal system within fractured, otherwise impermeable Franciscan metamorphic rocks. A deep water table of saline fluid has been postulated to be present under the steam field, but no chloride-rich water has been found at drillable depth. We propose that recently discovered, isotopically shifted steam in the northwest Geysers area indicates the presence not of deep connate water but rather of boiled-down, boron-rich Franciscan evolved meteoric water. This water is likely to be present in limited quantities and will not provide a significant hot water resource for geothermal power production at The Geysers field or from the main Clear Lake volcanic field. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. HARVARD UNIV,CAMBRIDGE,MA 02138. RP DONNELLYNOLAN, JM (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 76 TC 38 Z9 38 U1 1 U2 6 PU ECONOMIC GEOLOGY PUBL CO PI EL PASO PA UNIV TEXAS AT EL PASO ROOM 202 QUINN HALL, EL PASO, TX 79968 SN 0361-0128 J9 ECON GEOL BULL SOC JI Econ. Geol. Bull. Soc. Econ. Geol. PD MAR-APR PY 1993 VL 88 IS 2 BP 301 EP 316 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KY602 UT WOS:A1993KY60200005 ER PT J AU PALLER, KA AF PALLER, KA TI ELECTROPHYSIOLOGICAL STUDIES OF HUMAN-MEMORY SO EEG-EMG-ZEITSCHRIFT FUR ELEKTROENZEPHALOGRAPHIE ELEKTROMYOGRAPHIE UND VERWANDTE GEBIETE LA German DT Article DE EVENT-RELATED POTENTIALS; MEMORY; RECOGNITION; RECALL; ENCODING; P300 ID EVENT-RELATED POTENTIALS; CONTINUOUS RECOGNITION MEMORY; WORD REPETITION; BRAIN POTENTIALS; IMPLICIT MEMORY; FREQUENCY WORDS; LOBE; PERFORMANCE; PARADIGM; RECALL AB This review summarizes recent experiments that explored human memory processes using recordings of event-related potentials (ERPs) from the brain. In many studies, ERPs elicited by words presented during an acquisition stage have differed as a function of later recall or recognition. These ERP differences, generally in the 400 to 800 ms range, indicate that processes of memory encoding may produce ERP correlates. Numerous studies have also been devoted to ERP effects during recognition. In general, the second presentation of a stimulus was associated with an enhanced positivity relative to the first presentation or to new items. Similar effects have been observed in implicit memory tests in which repetitions were irrelevant to the subject's task. There has been some difficulty in relating these old/new effects to the processes that mediate memory experiences such as recollection and priming. However, a new paradigm that enables a dissociation between ERP correlates of recollection and priming is described. Studies of ERPs recorded from intracranial electrodes have also shown memory sensitivity, particularly for electrode locations near the hippocampus. In summary, ERPs may be useful as indices of both memory encoding and memory retrieval processes. RP PALLER, KA (reprint author), LAWRENCE BERKELEY LAB,CTR FUNCT IMAGING,1 CYCLOTRON RD,MAIL STOP 55-121,BERKELEY,CA 94720, USA. OI Paller, Ken/0000-0003-4415-4143 NR 65 TC 20 Z9 20 U1 1 U2 2 PU GEORG THIEME VERLAG PI STUTTGART PA P O BOX 30 11 20, D-70451 STUTTGART, GERMANY SN 0941-3790 J9 EEG-EMG-Z ELEK ELEKT JI EEG-EMG-Z. Elektroenz. Elektron. Geb. PD MAR PY 1993 VL 24 IS 1 BP 24 EP 33 PG 10 WC Engineering, Biomedical; Clinical Neurology SC Engineering; Neurosciences & Neurology GA LU777 UT WOS:A1993LU77700005 ER PT J AU MOHAN, T VERKADE, JG AF MOHAN, T VERKADE, JG TI DETERMINATION OF TOTAL PHENOL CONCENTRATIONS IN COAL-LIQUEFACTION RESIDS BY P-31 NMR-SPECTROSCOPY SO ENERGY & FUELS LA English DT Article ID LABILE HYDROGEN AB Fifteen coal liquefaction resids are quantitatively analyzed for phenolics and moisture using the P-31 NMR tagging agent ClPOCMe2CMe2O. Despite the presence of organic free radicals in these resids,which contributed to the breadth of the derivatized phenolic P-31 resonances, excellent agreement with the phenolic contents obtained by FTIR spectroscoPY was achieved. The best results were obtained by processing the P-31 NMR spectra with an NMRI matched filter apodization Program. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. NR 15 TC 9 Z9 13 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAR-APR PY 1993 VL 7 IS 2 BP 222 EP 226 DI 10.1021/ef00038a011 PG 5 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA KU830 UT WOS:A1993KU83000012 ER PT J AU MITCHELL, SC LAFFERTY, CJ GARCIA, R SNAPE, CE BUCHANAN, AC BRITT, PF KLAVETTER, E AF MITCHELL, SC LAFFERTY, CJ GARCIA, R SNAPE, CE BUCHANAN, AC BRITT, PF KLAVETTER, E TI SILICA-IMMOBILIZED COMPOUNDS AS MODELS FOR PROBING COAL PYROLYSIS AND HYDROPYROLYSIS PHENOMENA SO ENERGY & FUELS LA English DT Note ID THERMOLYSIS; HYDROGENOLYSIS; SURFACE C1 UNIV STRATHCLYDE,DEPT PURE & APPL CHEM,GLASGOW G1 1XL,SCOTLAND. OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RI Garcia, Roberto/J-6919-2014; OI Snape, Colin/0000-0002-6671-8766 NR 13 TC 16 Z9 16 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAR-APR PY 1993 VL 7 IS 2 BP 331 EP 333 DI 10.1021/ef00038a027 PG 3 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA KU830 UT WOS:A1993KU83000028 ER PT J AU SCHIPPER, L MEYERS, S AF SCHIPPER, L MEYERS, S TI USING SCENARIOS TO EXPLORE FUTURE ENERGY DEMAND IN INDUSTRIALIZED COUNTRIES SO ENERGY POLICY LA English DT Article DE OECD; ENERGY INTENSITIES; ENERGY DEMAND AB We present three scenarios of OECD average sectoral energy intensities in the year 2010. These represent the direction in which current and expected trends seem to be moving; what might happen if energy efficiency were given a high priority by governments and the private sector; and what might be achieved if restraining energy use became a very high priority for public policy (eg if CO2 emissions were recognized as a serious problem). The scenarios delineate an important (if somewhat vague) boundary between a relatively easily attainable improvement in efficiency and a more problematical level of change. With a mixture of pricing and other policies, they suggest that OECD primary energy use in 2010 could be 20-25% less than currently seems likely (or about equal to demand in 1989) if fairly determined efforts were made. To increase that reduction to 40-45% would be very challenging, but not impossible. RP SCHIPPER, L (reprint author), LAWRENCE BERKELEY LAB,ENERGY ANAL PROGRAM,BERKELEY,CA 94720, USA. NR 11 TC 5 Z9 5 U1 0 U2 0 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD MAR PY 1993 VL 21 IS 3 BP 264 EP 275 DI 10.1016/0301-4215(93)90248-E PG 12 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA KR182 UT WOS:A1993KR18200008 ER PT J AU SCHULER, CA RICKARD, WH SARGEANT, GA AF SCHULER, CA RICKARD, WH SARGEANT, GA TI CONSERVATION OF HABITATS FOR SHRUBSTEPPE BIRDS SO ENVIRONMENTAL CONSERVATION LA English DT Article AB Extending over a year, all the birds that could be detected were counted on two transects which together sampled an area of 1.39 km2. Only 37 species were recorded during 82 surveys. Total bird density during the spring (March-June) was 43.0 birds/km2, and the density for the entire year was 26.7 birdS/km2. The characteristic nesting birds were Western Meadowlark, Sage Sparrow, Burrowing Owl, Mourning Dove, Homed Lark, Long-billed Curlew, Lark Sparrow, and Loggerhead Shrike. Western Meadow-larks and Sage Sparrows were the most abundant nesting birds, having an average density of 11.2 and 7.8 birdS/km2, respectively. Seasonal distribution of birds varied with species, but most species were present only from March to September. Sixty-three per cent of the habitat surveyed was dominated by Big Sagebrush, 26% was dominated by Cheatgrass, and the remaining 11% was dominated by Spiny Hopsage. Big Sagebrush habitat supported a greater total bird density than the Cheatgrass or Hopsage habitats. Sage Sparrows were closely associated with Sagebrush habitats, while Western Meadowlarks showed no strong habitat affinities. Extensive habitat modifications induced by more than a century of agriculture and livestock grazing have greatly depleted native Shrubsteppe habitat in the Columbia Basin. Over the past 40 years, the Hanford Site has served as a refugium for Shrubsteppe habitat that supports populations of native Shrubsteppe birds. The concept of the Hanford Site as a refugium for native Shrubsteppe habitat and Shrubsteppe nesting birds is favourably discussed. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. RP SCHULER, CA (reprint author), US FISH & WILDLIFE SERV, PORTLAND FIELD OFF, 727 NE 24TH AVE, PORTLAND, OR 97232 USA. NR 26 TC 0 Z9 0 U1 4 U2 11 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 SN 0376-8929 J9 ENVIRON CONSERV JI Environ. Conserv. PD SPR PY 1993 VL 20 IS 1 BP 57 EP 64 PG 8 WC Biodiversity Conservation; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA LP091 UT WOS:A1993LP09100010 ER PT J AU TURTELTAUB, KW VOGEL, JS FRANTZ, C BUONARATI, MH FELTON, JS AF TURTELTAUB, KW VOGEL, JS FRANTZ, C BUONARATI, MH FELTON, JS TI LOW-LEVEL BIOLOGICAL DOSIMETRY OF HETEROCYCLIC AMINE CARCINOGENS ISOLATED FROM COOKED FOOD SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Article; Proceedings Paper CT CONF ON BIOMONITORING AND SUSCEPTIBILITY MARKERS IN HUMAN CANCER : APPLICATIONS IN MOLECULAR EPIDEMIOLOGY AND RISK ASSESSMENT CY OCT 26-NOV 01, 1991 CL KAILUA KONA, HI SP INT AGCY RES CANC, NATL CTR TOXICOL RES, US EPA, COMMISS EUROPEAN COMMUNITIES, NATL CANC INST ID ACCELERATOR MASS-SPECTROMETRY; BIO-MEDICAL SCIENCES; EXPOSURE; DNA AB The bioavailability and the bioreactivity of the carcinogenic heterocyclic amine 12-C-14]2-amino-1-methyl-6-phenyl-imidazo[4,5b]pyridine (PhIP) have been investigated at a dose approximating that likely from the human diet by accelerator mass spectrometry (AMS). 12-C-14]PhIP was administered to mice at a dose equivalent to the consumption of two 100 g beef patties (41 ng/kg). The biological half-life of PhIP was 1 hr, with 90% of the dose being excreted via the urine. Peak tissue PhIP concentrations were reached within 3 hr, with the highest levels in the tissues of the gastrointestinal tract, followed by the liver, kidney, pancreas, and thymus. Since the detection limit by AMS is dependent on the natural abundance of C-14, we have achieved further increases in sensitivity by producing mice that have 20% of the natural abundance of C-14. Use of these C-14-depleted animals allows measurements to be made near the natural level of exposure for many environmental carcinogens. PhIP-DNA adduct levels have also been measured by P-32-postlabeling at doses of 1.0, 10, and 20 mg/kg. The highest adduct levels were found in the pancreas, thymus, heart, and liver and increased linearly with dose. The principal adducts are derived from guanine. C1 LAWRENCE LIVERMORE NATL LAB,CTR ACCELERATOR MASS SPECTROMETRY,LIVERMORE,CA 94550. RP TURTELTAUB, KW (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI L452,LIVERMORE,CA 94550, USA. NR 9 TC 12 Z9 12 U1 0 U2 1 PU NATL INST ENVIRON HEALTH SCI PI RES TRIANGLE PK PA PO BOX 12233, RES TRIANGLE PK, NC 27709 SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD MAR PY 1993 VL 99 BP 183 EP 186 PG 4 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA LC430 UT WOS:A1993LC43000029 PM 8319619 ER PT J AU VANDERLAAN, M HWANG, M DJANEGARA, T AF VANDERLAAN, M HWANG, M DJANEGARA, T TI IMMUNOAFFINITY PURIFICATION OF DIETARY HETEROCYCLIC AMINE CARCINOGENS SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Article; Proceedings Paper CT CONF ON BIOMONITORING AND SUSCEPTIBILITY MARKERS IN HUMAN CANCER : APPLICATIONS IN MOLECULAR EPIDEMIOLOGY AND RISK ASSESSMENT CY OCT 26-NOV 01, 1991 CL KAILUA KONA, HI SP INT AGCY RES CANC, NATL CTR TOXICOL RES, US EPA, COMMISS EUROPEAN COMMUNITIES, NATL CANC INST ID MONOCLONAL-ANTIBODIES; BEEF AB Cooking meats produces a family of heterocylic aromatic amines that are calcinogens in rodents and genotoxic in many short-term assays. Concern that these compounds may be human carcinogens has prompted us to develop immunochemical methods for quantifying these compounds in the human diet and for identifying the parent compounds and metabolites in urine and feces. Previously reported monoclonal antibodies to 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 6-phenyl-2-amino-1-methylimidazo[4,5-f]pyridine (PhIP) were used to purify by immunoaffinity these known mutagens and cross-reacting structural analogs from well-done cooked beef and urine samples. Materials recovered from the immunoaffinity columns were subsequently separated by HPLC to purify the known mutagens from cross-reacting chemicals that co-purify by immunoaffinity. Immunoaffinity chromatography was found to be a rapid means of quantifying individual known mutagens, with a minimum of precolumn sample clean-up required. In addition, this procedure has yielded several new mutagens present in cooked meats that are apparently structural analogs of PhIP. Immunoaffinity techniques were also used to purify metabolites from the urine of rats and humans exposed to MeIQx or PhIP For MeIQx-exposed rats, the combination antibodies immunoconcentrated 75% of the total urinary radioactivity. Analysis of PhIP metabolites recovered from antibody columns is facilitated by the intrinsic fluorescence of PhIP and its metabolites, providing sufficient sensitivity to monitor individuals for the levels of PhIP excreted following consumption of typical western diets. RP VANDERLAAN, M (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,POB 5507,LIVERMORE,CA 94550, USA. FU NCI NIH HHS [R01 CA40811-03, VO1 CA48446-02] NR 6 TC 5 Z9 5 U1 0 U2 1 PU NATL INST ENVIRON HEALTH SCI PI RES TRIANGLE PK PA PO BOX 12233, RES TRIANGLE PK, NC 27709 SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD MAR PY 1993 VL 99 BP 285 EP 287 PG 3 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA LC430 UT WOS:A1993LC43000054 PM 8319645 ER PT J AU COMPTONQUINTANA, PJE JENSEN, RH BIGBEE, WL GRANT, SG LANGLOIS, RG SMITH, MT RAPPAPORT, SM AF COMPTONQUINTANA, PJE JENSEN, RH BIGBEE, WL GRANT, SG LANGLOIS, RG SMITH, MT RAPPAPORT, SM TI USE OF THE GLYCOPHORIN-A HUMAN MUTATION ASSAY TO STUDY WORKERS EXPOSED TO STYRENE SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Article; Proceedings Paper CT CONF ON BIOMONITORING AND SUSCEPTIBILITY MARKERS IN HUMAN CANCER : APPLICATIONS IN MOLECULAR EPIDEMIOLOGY AND RISK ASSESSMENT CY OCT 26-NOV 01, 1991 CL KAILUA KONA, HI SP INT AGCY RES CANC, NATL CTR TOXICOL RES, US EPA, COMMISS EUROPEAN COMMUNITIES, NATL CANC INST ID ERYTHROCYTES; FREQUENCY; EXPRESSION; PHENOTYPES; TOXICOLOGY; LOCUS AB The glycophorin A (GPA) assay is a human mutation assay that is potentially useful for large epidemiological studies. The assay is rapid and requires a minimal amount of blood, which can be stored before analysis. The data presented here were collected from workers exposed to styrene in a boat manufacturing plant. This study was the first to apply the GPA assay to an occupationally exposed population. Subjects with a mean styrene exposure of 30 ppm had a higher frequency of GPA NPHI variant cells than subjects with mean exposure of 1 ppm, but the subjects differed in respect to smoking and age distribution. Results indicate that the original 1-W-1 version of the assay may not be suitable for studies of small numbers of exposed subjects due to variability and artifacts. The newer BR6 version, however, has much lower variability and shows promise for use in the occupational setting. C1 UNIV CALIF BERKELEY,DEPT ENVIRONM HLTH SCI,BERKELEY,CA 94720. LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,LIVERMORE,CA 94550. RI Grant, Stephen/D-6984-2014 OI Grant, Stephen/0000-0002-9236-0913 FU NCI NIH HHS [CA48518] NR 14 TC 11 Z9 11 U1 0 U2 0 PU NATL INST ENVIRON HEALTH SCI PI RES TRIANGLE PK PA PO BOX 12233, RES TRIANGLE PK, NC 27709 SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD MAR PY 1993 VL 99 BP 297 EP 301 DI 10.2307/3431505 PG 5 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA LC430 UT WOS:A1993LC43000057 PM 8319648 ER PT J AU KORTE, NE BROWN, DE AF KORTE, NE BROWN, DE TI REFEREE ANALYSES - A BETTER APPROACH THAN DATA VALIDATION SO ENVIRONMENTAL MANAGEMENT LA English DT Article DE DATA VALIDATION; QUALITY ASSURANCE; CONTRACT LABORATORY PROGRAM AB Data validation, as prescribed in guidance documents provided by the United States Environmental Protection Agency (EPA), yields legal evidence that an analytical laboratory has performed analyses according to predetermined specifications. This validation process, because it involves only the checking of procedural documentation, provides minimal information concerning the technical validity of the data. Unfortunately, in the minds of many, the performance of such a data validation has become synonymous with technical validity. A better approach is to implement a routine program of referee analyses. That is, submit a predetermined number of samples from the project to a second laboratory. A routine program of this type provides a self-checking and self-correcting mechanism for determining whether data are technically valid. C1 ALLIED SIGNAL AEROSP,DEPT ENVIRONM SAFETY & HLTH,KANSAS CITY DIV,KANSAS CITY,MO 64131. RP KORTE, NE (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,GRAND JUNCT OFF,GRAND JCT,CO 81502, USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0364-152X J9 ENVIRON MANAGE JI Environ. Manage. PD MAR-APR PY 1993 VL 17 IS 2 BP 277 EP 280 DI 10.1007/BF02394697 PG 4 WC Environmental Sciences SC Environmental Sciences & Ecology GA KL476 UT WOS:A1993KL47600013 ER PT J AU TRAVIS, CC MACINNIS, JM AF TRAVIS, CC MACINNIS, JM TI ORGANICS IN SOILS - REPLY SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Letter RP TRAVIS, CC (reprint author), OAK RIDGE NATL LAB,CTR RISK MANAGEMENT,OAK RIDGE,TN 37831, USA. 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 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD MAR PY 1993 VL 27 IS 3 BP 420 EP 421 PG 2 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA KP133 UT WOS:A1993KP13300003 ER PT J AU GARBESI, K SEXTRO, RG FISK, WJ MODERA, MP REVZAN, KL AF GARBESI, K SEXTRO, RG FISK, WJ MODERA, MP REVZAN, KL TI SOIL-GAS ENTRY INTO AN EXPERIMENTAL BASEMENT - MODEL MEASUREMENT COMPARISONS AND SEASONAL EFFECTS SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID RADON ENTRY; AIR-FLOW; PRESSURE; HOUSES; TRANSPORT AB Previous studies have reported a large and persistent discrepancy between field measurements and model predictions of pressure-driven entry of soil gas into houses-the phenomenon that causes high concentrations of radon indoors. The discrepancy is often attributed to poor understanding of inherently complex field sites. This paper compares measurements of soil-gas entry made at a full-scale test basement located in natural solid with predictions of a three-dimensional finite difference model. The results corroborate the earlier findings, with the model underpredicting the soil-gas entry rate by a factor of 7. The effect of seasonal changes in soil conditions on soil-gas entry is also examined. Despite large seasonal changes in near-surface soil moisture content and air permeability, there is no observable effect on soil-gas entry, apparently because critical soil conditions near the soil-gas entry location in the structure floor remain relatively constant. C1 LAWRENCE BERKELEY LAB,INDOOR ENVIRONM PROGRAM,BERKELEY,CA 94720. NR 24 TC 42 Z9 42 U1 0 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD MAR PY 1993 VL 27 IS 3 BP 466 EP 473 DI 10.1021/es00040a003 PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA KP133 UT WOS:A1993KP13300009 ER PT J AU RITHIDECH, KN BOND, VP CRONKITE, EP THOMPSON, MH AF RITHIDECH, KN BOND, VP CRONKITE, EP THOMPSON, MH TI A SPECIFIC CHROMOSOMAL DELETION IN MURINE LEUKEMIC-CELLS INDUCED BY RADIATION WITH DIFFERENT QUALITIES SO EXPERIMENTAL HEMATOLOGY LA English DT Article DE RADIATION; CHROMOSOME; DELETION; MURINE; MYELOID LEUKEMIA ID MYELOID-LEUKEMIA; TUMORS; IDENTIFICATION; MICE AB G-banded metaphase chromosomes prepared from 14 male CBA/Ca mice with histologically confirmed myeloid leukemia (ML) were studied in an effort to identify specific chromosomal changes associated with radiation leukemogenesis. The chromosome studies were undertaken as part of a larger investigation of radiation carcinogenesis, in which mice were exposed to radiation of several different qualities, i.e., x-rays, gamma-rays and ''monoenergetic'' fast neutrons of 5 mean energies ranging from 0.2 to 14 MeV. The 14 ML cases showed no histologically phenotypic differences and they were transplantable in syngeneic mice. We detected a specific chromosomal deletion in 1 copy of mouse chromosome 2 at regions D-E in all radiation-induced ML cells, regardless of radiation quality. Our results strongly implicate the involvement of genes within or close to regions D-E of chromosome 2 in radiation leukemogenesis. In addition to the specific deletion in chromosome 2, loss or gain of the Y chromosome was also detected in some cells from 6 ML cases. Because this hypo- or hyperploidy occurred in only a small fraction of leukemic cells, a causative role in radiation leukemogenesis appears unlikely. RP RITHIDECH, KN (reprint author), BROOKHAVEN NATL LAB,DEPT MED,BLDG 490,UPTON,NY 11973, USA. NR 20 TC 38 Z9 38 U1 0 U2 0 PU CARDEN JENNINGS PUBL CO LTD PI CHARLOTTESVILLE PA BLAKE CTR, STE 200, 1224 W MAIN ST, CHARLOTTESVILLE, VA 22903 SN 0301-472X J9 EXP HEMATOL JI Exp. Hematol. PD MAR PY 1993 VL 21 IS 3 BP 427 EP 431 PG 5 WC Hematology; Medicine, Research & Experimental SC Hematology; Research & Experimental Medicine GA MW608 UT WOS:A1993MW60800006 PM 8440340 ER PT J AU Cox, BL Wang, JSY AF Cox, B. Lea Wang, J. S. Y. TI FRACTAL SURFACES: MEASUREMENT AND APPLICATIONS IN THE EARTH SCIENCES SO FRACTALS-COMPLEX GEOMETRY PATTERNS AND SCALING IN NATURE AND SOCIETY LA English DT Review ID SOIL-WATER PROPERTIES; SAN-ANDREAS FAULT; MULTISCALE SOURCES; SPATIAL VARIATION; SANDSTONE PORES; SELF-AFFINITY; GEOMETRY; ROCK; DIMENSIONS; CONDUCTIVITY AB Earth scientists have measured fractal dimensions of surfaces by different techniques, including the divider, box, triangle, slit-island, power spectral, variogram and distribution methods. We review these seven measurement techniques, finding that fractal dimensions may vary systematically with measurement method. We discuss possible reasons for these differences, and point to common problems shared by all of the methods, including the remainder problem, curve-fitting, orientation of the measurement plane, size and direction of the sample. Fractal measurements have been applied to many problems in the earth sciences, at a wide range of spatial scales. These include map data of topography; fault traces and fracture networks; fracture surfaces of natural rocks, both in the field and at laboratory scales; metal surfaces; porous aggregate geometry; flow and transport through heterogenous systems; and various microscopic surface phenomena associated with adsorption, aggregation, erosion and chemical dissolution. We review these applications and discuss the usefulness and limitations of fractal analysis to these types of problems in the earth sciences. C1 [Cox, B. Lea; Wang, J. S. Y.] Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94706 USA. RP Cox, BL (reprint author), Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94706 USA. FU Sandia National Laboratories; Yucca Mountain Site Characterization Office; Regulatory and Site Evaluation Division under U.S Department of Energy [DE-AC03-76SF00098] FX The authors gratefully acknowledge critical review by Drs. Robert Zimmerman, Steve Martel, Nigel Quinn, and Yvonne Tsang, all of the Earth Sciences Division, Lawrence Berkeley Laboratory, and by the anonymous reviewers. The suggestions by the various reviewers improved the clarity of this paper. Valuable discussion and suggestions were given by Professor Garrison Sposito, University of California, Berkeley. This work was supported by Sandia National Laboratories, and the Director, Office of Civilian Radioactive Waste Management, Yucca Mountain Site Characterization Office, Regulatory and Site Evaluation Division under U.S Department of Energy Contract No. DE-AC03-76SF00098. NR 78 TC 117 Z9 119 U1 3 U2 10 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0218-348X J9 FRACTALS JI Fractals-Complex Geom. Patterns Scaling Nat. Soc. PD MAR PY 1993 VL 1 IS 1 BP 87 EP 115 DI 10.1142/S0218348X93000125 PG 29 WC Mathematics, Interdisciplinary Applications; Multidisciplinary Sciences SC Mathematics; Science & Technology - Other Topics GA V18WV UT WOS:000208035800012 ER PT J AU KONDO, T OHNO, H JAMESON, RA HASSBERGER, JA AF KONDO, T OHNO, H JAMESON, RA HASSBERGER, JA TI HIGH-ENERGY INTENSITY NEUTRON FACILITIES FOR TESTING FUSION MATERIALS SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 17TH SYMP ON FUSION TECHNOLOGY ( SOFT 17 ) CY SEP 14-18, 1992 CL ROME, ITALY ID IRRADIATION TEST FACILITY; ESNIT AB The current status of technology of neutron irradiation test facilities for the development of fusion materials is described focussing to those with a high feasibility of being constructed and brought into operation within a decade. Regarding the facility concept the system with the deuteron-lithium(d-Li) stripping type source has been considered as the most realistic among the currently conceivable candidates. A series of systematic surveys on facility design and neutron field characteristics made recently by an international working group have reached the same conclusion. The base technology developed earlier by the FMIT Project (Fusion Materials Testing Facility Project, 1978-1985) has recently been advanced in the accelerator technology aspect. In Japan, the ESNIT Program has been promoted since 1988, in which the capability of energy selectivity has drawn special attention in resolving the issues specific to the d-Li system. Considering designing, constructing and applying such a type of facility, a realism for a strategy of a staged upgrading process was proposed, in which the actions are to start from a medium size unit module being followed by increasing the test volume in accordance with the progress of the materials development towards the DEMO reactor. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP KONDO, T (reprint author), JAPAN ATOM ENERGY RES INST,TOKAI RES ESTAB,TOKAI,IBARAKI 31911,JAPAN. NR 34 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD MAR PY 1993 VL 22 IS 1-2 BP 117 EP 127 DI 10.1016/S0920-3796(05)80013-4 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA LD612 UT WOS:A1993LD61200012 ER PT J AU STORMS, E AF STORMS, E TI MEASUREMENTS OF EXCESS HEAT FROM A PONS-FLEISCHMANN-TYPE ELECTROLYTIC CELL USING PALLADIUM SHEET SO FUSION TECHNOLOGY LA English DT Note DE EXCESS HEAT MEASUREMENT; CALORIMETRY; PALLADIUM ID TRANSMISSION RESONANCE MODEL; COLD FUSION REACTION; CALORIMETRIC MEASUREMENTS; NUCLEAR-FUSION; DEUTERIUM; WATER; ACHIEVEMENT; RELEASE; SYSTEM AB Two pieces of palladium sheet similar to that used by Takahashi were loaded with deuterium in a Pons-Fleischmann-type electrolytic cell, and heat production was measured. One sheet produced a steady increase in excess power that reached 7.5 W (20% of input power) before the study was interrupted. A second similar sheet from a different batch of palladium did not produce any measurable excess power. There were differences in the loading behavior, the maximum stoichiometry, and the presence of excess volume in the deuteride made from these materials. The first sheet contained 0.8% excess volume after having been deloaded from its maximum deuterium/palladium (D/Pd) ratio of 0.82 to 0.73, and the second sheet contained 13.5% excess volume while at its maximum ratio of 0.75. The high excess volume in the latter case is an indication of internal escape paths that reduce the required high D/Pd ratio. RP STORMS, E (reprint author), LOS ALAMOS NATL LAB,DIV NMT,LOS ALAMOS,NM 87545, USA. NR 64 TC 6 Z9 6 U1 1 U2 2 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 MAR PY 1993 VL 23 IS 2 BP 230 EP 245 PG 16 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KN121 UT WOS:A1993KN12100008 ER PT J AU SANFORD, J KIM, BW DEAVEN, LL JONES, C HIGGINS, MJ NOWAK, NJ SHOWS, TB AF SANFORD, J KIM, BW DEAVEN, LL JONES, C HIGGINS, MJ NOWAK, NJ SHOWS, TB TI A HUMAN CHROMOSOME-11 NOTI END CLONE LIBRARY SO GENOMICS LA English DT Article ID LINKING LIBRARY; PHYSICAL MAP; GENE; CONSTRUCTION; DNA; MARKERS; REGION; HYBRIDIZATION; BAND-11Q23; SEQUENCES C1 NEW YORK STATE DEPT HLTH,ROSWELL PK MEM INST,DEPT HUMAN GENET,BUFFALO,NY 14263. LOS ALAMOS NATL LAB,CTR HUMAN GENOME STUDIES,LOS ALAMOS,NM 87545. ELEANOR ROOSEVELT INST CANC RES,DEPT HUMAN GENET,DENVER,CO 80206. FU NHGRI NIH HHS [HG00359, HG00333] NR 33 TC 8 Z9 8 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 0888-7543 J9 GENOMICS JI Genomics PD MAR PY 1993 VL 15 IS 3 BP 653 EP 658 DI 10.1006/geno.1993.1120 PG 6 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA KU531 UT WOS:A1993KU53100025 PM 8468060 ER PT J AU TAIT, CD JANECKY, DR AF TAIT, CD JANECKY, DR TI SPECIATION OF AQUEOUS PALLADIUM(II) CHLORIDE SOLUTIONS USING OPTICAL SPECTROSCOPIES - REPLY SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Note RP TAIT, CD (reprint author), LOS ALAMOS NATL LAB,DIV INC,MS-J514,LOS ALAMOS,NM 87545, USA. NR 6 TC 2 Z9 2 U1 1 U2 3 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 MAR PY 1993 VL 57 IS 5 BP 1157 EP 1157 DI 10.1016/0016-7037(93)90048-2 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KR473 UT WOS:A1993KR47300017 ER PT J AU STURCHIO, NC BOHLKE, JK MARKUN, FJ AF STURCHIO, NC BOHLKE, JK MARKUN, FJ TI RADIUM ISOTOPE GEOCHEMISTRY OF THERMAL WATERS, YELLOWSTONE-NATIONAL-PARK, WYOMING, USA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT SESSION ON ACTINIDE SERIES DISEQUILIBRIA IN IGNEOUS AND GEOTHERMAL PROCESSES, AT THE 1991 ANNUAL MEETING OF THE GEOLOGICAL SOC OF AMERICA CY OCT 21-24, 1991 CL SAN DIEGO, CA SP GEOL SOC AMER ID PLATEAU VOLCANIC FIELD; LOWER GEYSER BASIN; STATES GULF-COAST; DRILL HOLE Y-2; HYDROTHERMAL ALTERATION; GEOTHERMAL WATERS; RHYOLITIC MAGMA; GROUNDWATERS; THORIUM; URANIUM AB Radium isotope activities (Ra-226, Ra-228, and Ra-224), chemical compositions, and sulfur isotope ratios in sulfate were determined for water samples from thermal areas in Yellowstone National Park, Wyoming. Activities of Ra-226 in these waters range from <0.2 to 37.9 dpm/kg. Activity ratios of Ra-228/Ra-226 range from 0.26 to 14.2, and those of Ra-224 /Ra-228 range from 0.73 to 3. 1. Radium concentrations are inversely correlated with aquifer equilibration temperatures (estimated from dissolved silica concentrations), while [ Ra/Ba]aq and Ra-228 / Ra-226 activity ratios depend upon U / Ba and Th / U ratios in aquifer rocks. Major controls on Ra concentration in Yellowstone thermal waters are inferred to be ( 1 ) barite saturation (at Norris Geyser Basin, Mammoth Hot Springs, and other northern areas) and (2) zeolite-water ion exchange (at Upper Geyser Basin). The data are consistent with a model in which ( 1 ) radium and barium are supplied to water by bulk dissolution of aquifer rock, and (2) chemical equilibration of water with rock is rapid relative to the 1602 year half-life of Ra-226. The Ra-228 / Ra-226 activity ratios of the waters may in some cases reflect surface enrichments of Th-232 and/or may indicate that alpha-recoil input of Ra-228 is rapid relative to water-rock chemical equilibration. Activity ratios of Ra-224 /Ra-228 indicate a nearly ubiqUitoUS Ra-224 excess that generally increases with decreasing pH. Near-surface (less-than-or-equal-to 100 m) thermal water flow velocities at Mammoth Hot Springs are estimated from Ra-224 / Ra-228 variation to be greater-than-or-equal-to 1 m h-1. RP STURCHIO, NC (reprint author), ARGONNE NATL LAB,CMT-205,ARGONNE,IL 60439, USA. NR 72 TC 26 Z9 26 U1 2 U2 6 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 MAR PY 1993 VL 57 IS 6 BP 1203 EP 1214 DI 10.1016/0016-7037(93)90057-4 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KW203 UT WOS:A1993KW20300003 ER PT J AU SCHAEFER, SJ STURCHIO, NC MURRELL, MT WILLIAMS, SN AF SCHAEFER, SJ STURCHIO, NC MURRELL, MT WILLIAMS, SN TI INTERNAL U-238 SERIES SYSTEMATICS OF PUMICE FROM THE NOVEMBER 13, 1985, ERUPTION OF NEVADO-DEL-RUIZ, COLOMBIA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT SESSION ON ACTINIDE SERIES DISEQUILIBRIA IN IGNEOUS AND GEOTHERMAL PROCESSES, AT THE 1991 ANNUAL MEETING OF THE GEOLOGICAL SOC OF AMERICA CY OCT 21-24, 1991 CL SAN DIEGO, CA SP GEOL SOC AMER ID TH; VOLCANO; DISEQUILIBRIA AB High-precision mass spectrometer and alpha scintillation measurements of U-238-series nuclides were obtained for whole-rock pumice and constituent mineral and glass separates to help interpret the timing and nature of magmatic processes that led up to the 1985 eruption of Nevado del Ruiz volcano. Internal isochron diagrams for (Ra-226)/Ba vs. (Th-230)/Ba and (Th-230/Th-232) vs. (U-238/Th-232) show that data define linear arrays, indicating an average crystallization age of 6.1 +/- 0.5 ka (Ra-Th isochron) and 7 +/- 6 ka (Th-U isochron). Stratigraphic, petrographic, geochemical, repose time, and eruption volume data for the Holocene eruptive sequence of Nevado del Ruiz indicate that significant changes occurred in the subvolcanic magma chamber between eruptions R9 ( almost-equal-to 8.6 ka) and R8 ( almost-equal-to 3.0 ka). This coincides with the average crystallization age derived from the U-series data and may represent the injection of a new batch (or batches) of mantle-derived magma into the subvolcanic magma chamber. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP SCHAEFER, SJ (reprint author), ARIZONA STATE UNIV,DEPT GEOL,TEMPE,AZ 85287, USA. NR 26 TC 34 Z9 35 U1 0 U2 5 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 MAR PY 1993 VL 57 IS 6 BP 1215 EP 1219 DI 10.1016/0016-7037(93)90058-5 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KW203 UT WOS:A1993KW20300004 ER PT J AU VOLPE, AM GOLDSTEIN, SJ AF VOLPE, AM GOLDSTEIN, SJ TI RA-226 TH-230 DISEQUILIBRIUM IN AXIAL AND OFF-AXIS MIDOCEAN RIDGE BASALTS SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT SESSION ON ACTINIDE SERIES DISEQUILIBRIA IN IGNEOUS AND GEOTHERMAL PROCESSES, AT THE 1991 ANNUAL MEETING OF THE GEOLOGICAL SOC OF AMERICA CY OCT 21-24, 1991 CL SAN DIEGO, CA SP GEOL SOC AMER ID EAST PACIFIC RISE; JUAN-DE-FUCA; RADIOACTIVE DISEQUILIBRIA; ISOTOPIC SYSTEMATICS; VOLCANIC-ROCKS; GORDA RIDGES; TH; MAGMA; BENEATH; MANTLE AB We describe Ra-226-Th-230 disequilibrium in mid-ocean ridge basalt (MORB) glasses from the Juan de Fuca, Gorda, and East Pacific ridges. These first mass spectrometric measurements of Ra-226 in MORB glasses at sub-picogram abundance levels confirm the large excesses over Th-230 determined by radon-emanation techniques and alpha spectrometry. All off-axis MORB glasses have Ra-226-Th-230 and U-234-U-238 in secular equilibrium. This suggests that magmatic processes, not secondary post-eruption alteration, generate U-238-series disequilibrium in these MORB. Least evolved, N-MORB from axial valleys have (Ra-226 /Th-230) between 2.2-2.3. Differentiated and enriched E-type MORB have consistently low (Ra-226 /Th-230) ratios compared with N-MORB from the same ridge sections. Ra-Th fractionation may be less pronounced, or magma residence-transit periods may be long for differentiated MORB. Also, E-MORB may be generated by different melt extraction volumes and rates. Estimated Ra-226-Th-230 ages for N-MORB agree with location on and off ridge segments, and with Th-U model ages. These preliminary results show that Ra-226-Th-230 disequilibrium could be used to quantify volcanic episodicity at ocean ridges. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP VOLPE, AM (reprint author), LAWRENCE LIVERMORE NATL LAB,L-232,LIVERMORE,CA 94550, USA. NR 37 TC 70 Z9 71 U1 1 U2 4 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 MAR PY 1993 VL 57 IS 6 BP 1233 EP 1241 DI 10.1016/0016-7037(93)90060-A PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KW203 UT WOS:A1993KW20300006 ER PT J AU GRAEDEL, TE BATES, TS BOUWMAN, AF CUNNOLD, D DIGNON, J FUNG, I JACOB, DJ LAMB, BK LOGAN, JA MARLAND, G MIDDLETON, P PACYNA, JM PLACET, M VELDT, C AF GRAEDEL, TE BATES, TS BOUWMAN, AF CUNNOLD, D DIGNON, J FUNG, I JACOB, DJ LAMB, BK LOGAN, JA MARLAND, G MIDDLETON, P PACYNA, JM PLACET, M VELDT, C TI A COMPILATION OF INVENTORIES OF EMISSIONS TO THE ATMOSPHERE SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Review ID GENERAL-CIRCULATION MODEL; SURFACE AIR-TEMPERATURE; ZONE COLOR SCANNER; NITROUS-OXIDE; HYDROCARBON EMISSIONS; ANTHROPOGENIC SOURCES; GLOBAL DISTRIBUTION; METHANE EMISSIONS; DIOXIDE EMISSIONS; EARTHS ATMOSPHERE AB Detailed and accurate emissions inventories are essential for reliable computer dispersion model simulation of the behavior of chemically and radiatively important atmospheric species. Currently, model simulations of the atmosphere are limited by the paucity of quality emissions data for input. As a first step in providing internationally recognized emissions inventories, we list here the inventories that are extant, together with their spatial and temporal characteristics and a few interpretive comments. The only global emissions inventory we regard as good is that for chlorofluorocarbons. Those for CO2, CH4, NO(x), SO2, reduced sulfur, and radon we regard as fair. In selected regions, the spatial resolution of emissions is well determined for CO2, CO, NO(x), and SO2. The temporal resolution of existing inventories is almost uniformly poor. Much remains to be done to generate emissions inventories adequate to fully support computer models of regional and global chemistry and climate. C1 PACIFIC NW LAB, WASHINGTON, DC 20024 USA. NOAA, PACIFIC MARINE ENVIRONM LAB, SEATTLE, WA 98115 USA. NATL INST PUBL HLTH & ENVIRONM PROTECT, 3720 BA BILTHOVEN, NETHERLANDS. GEORGIA INST TECHNOL, SCH GEOPHYS SCI, ATLANTA, GA 30332 USA. LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. NASA, GODDARD SPACE FLIGHT CTR, GREENBELT, MD 20771 USA. HARVARD UNIV, DEPT EARTH & PLANETARY SCI, CAMBRIDGE, MA 02138 USA. WASHINGTON STATE UNIV, DEPT CIVIL ENGN, ATMOSPHER RES LAB, PULLMAN, WA 99164 USA. OAK RIDGE NATL LAB, DIV ENVIRONM SCI, OAK RIDGE, TN 37831 USA. SUNY ALBANY, ALBANY, NY 12222 USA. NORWEGIAN INST AIR RES, N-2001 LILLESTROM, NORWAY. NETHERLANDS ORG APPL SCI RES, APELDOOM, NETHERLANDS. RP AT&T BELL LABS, ROOM 1D-349, MURRAY HILL, NJ 07974 USA. RI Bouwman, Lex/B-7053-2012; Bouwman, Lex/F-1444-2015; Bates, Timothy/L-6080-2016 OI Bouwman, Lex/0000-0002-2045-1859; NR 198 TC 67 Z9 68 U1 1 U2 19 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0886-6236 EI 1944-9224 J9 GLOBAL BIOGEOCHEM CY JI Glob. Biogeochem. Cycle PD MAR PY 1993 VL 7 IS 1 BP 1 EP 26 DI 10.1029/92GB02793 PG 26 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA KW450 UT WOS:A1993KW45000001 ER PT J AU RAYNER, S AF RAYNER, S TI SPECIAL ISSUE - NATIONAL CASE-STUDIES OF INSTITUTIONAL CAPABILITIES TO IMPLEMENT GREENHOUSE-GAS REDUCTIONS - INTRODUCTION SO GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS LA English DT Editorial Material RP RAYNER, S (reprint author), PACIFIC NW LAB, 901 D ST SW, SUITE 900, WASHINGTON, DC 20024 USA. OI rayner, steve/0000-0001-6779-9345 NR 0 TC 3 Z9 3 U1 0 U2 0 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0959-3780 J9 GLOBAL ENVIRON CHANG JI Glob. Environ. Change - Human Policy Dimens. PD MAR PY 1993 VL 3 IS 1 BP 7 EP 11 DI 10.1016/0959-3780(93)90011-9 PG 5 WC Environmental Sciences; Environmental Studies; Geography SC Environmental Sciences & Ecology; Geography GA LF771 UT WOS:A1993LF77100002 ER PT J AU RAYNER, S AF RAYNER, S TI PROSPECTS FOR CO2 EMISSIONS REDUCTION POLICY IN THE USA SO GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS LA English DT Article AB This article examines the US political context and the prospect for greenhouse gas reduction policies throughout the energy system. The USA's historic reliance on abundant fossil fuels is exacerbated by the confrontational nature of the global environmental debate in the country, occurring in an open political system that empowers dissenters to impede policy developments that may disadvantage them. The author anticipates a major change in US rhetoric with the advent of a new administration, although the core commitment of the USA to a comprehensive policy, including all sources and sinks of all greenhouse gases, is not expected to change. Energy-efficiency measures can be implemented soon, provided they do not entail lifestyle changes. In the medium term, the USA may make the most cost-effective contribution to global emissions reductions by technology transfer to developing countries, leaving domestic fossil fuel reductions to the long term. RP RAYNER, S (reprint author), PACIFIC NW LAB, 901 D ST SW, SUITE 900, WASHINGTON, DC 20024 USA. OI rayner, steve/0000-0001-6779-9345 NR 0 TC 2 Z9 2 U1 0 U2 0 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0959-3780 J9 GLOBAL ENVIRON CHANG JI Glob. Environ. Change - Human Policy Dimens. PD MAR PY 1993 VL 3 IS 1 BP 12 EP 31 DI 10.1016/0959-3780(93)90012-A PG 20 WC Environmental Sciences; Environmental Studies; Geography SC Environmental Sciences & Ecology; Geography GA LF771 UT WOS:A1993LF77100003 ER PT J AU PETRICH, CH AF PETRICH, CH TI INDONESIA AND GLOBAL CLIMATE-CHANGE NEGOTIATIONS - POTENTIAL OPPORTUNITIES AND CONSTRAINTS FOR PARTICIPATION, LEADERSHIP, AND COMMITMENT SO GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS LA English DT Article AB The author discusses factors likely to affect Indonesia's participation in global climate change mitigation negotiations. These include Indonesia's performance to date in the international arena and its track record for compliance with agreements; domestic challenges such as demographic pressures, economic growth, deforestation, and energy consumption; the institutional culture of the government; and the activities and limitations of the legal system, non-governmental organizations, and business. The author concludes that, while the Indonesian government may be a vocal advocate for 'sustainable development', it has little ability to follow through on large-scale commitments to international efforts because of issues It faces at home. RP PETRICH, CH (reprint author), OAK RIDGE NATL LAB,BLDG 4500-N,MS-6206,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 2 Z9 2 U1 0 U2 2 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0959-3780 J9 GLOBAL ENVIRON CHANG JI Glob. Environ. Change - Human Policy Dimens. PD MAR PY 1993 VL 3 IS 1 BP 53 EP 77 DI 10.1016/0959-3780(93)90014-C PG 25 WC Environmental Sciences; Environmental Studies; Geography SC Environmental Sciences & Ecology; Geography GA LF771 UT WOS:A1993LF77100005 ER PT J AU PERLACK, RD RUSSELL, M SHEN, ZM AF PERLACK, RD RUSSELL, M SHEN, ZM TI REDUCING GREENHOUSE-GAS EMISSIONS IN CHINA - INSTITUTIONAL, LEGAL AND CULTURAL CONSTRAINTS AND OPPORTUNITIES SO GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS LA English DT Article AB If the industrialized countries take steps to reduce their emissions and contribute money and technology for developing countries to do their part, China will participate in an international global warming treaty. Without these measures, the Chinese are not going to push greenhouse gas reductions on their own because they have more pressing problems. If the world wants them to move on greenhouse gas reduction, the relative incentives to the Chinese have to change in their favour, especially in light of the fact that they have not used up their share of the global commons. RP PERLACK, RD (reprint author), OAK RIDGE NATL LAB,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 1 Z9 1 U1 0 U2 3 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0959-3780 J9 GLOBAL ENVIRON CHANG JI Glob. Environ. Change - Human Policy Dimens. PD MAR PY 1993 VL 3 IS 1 BP 78 EP 100 DI 10.1016/0959-3780(93)90015-D PG 23 WC Environmental Sciences; Environmental Studies; Geography SC Environmental Sciences & Ecology; Geography GA LF771 UT WOS:A1993LF77100006 ER PT J AU NICHOLS, WE FRESHLEY, MD AF NICHOLS, WE FRESHLEY, MD TI UNCERTAINTY ANALYSES OF UNSATURATED ZONE TRAVEL TIME AT YUCCA MOUNTAIN SO GROUND WATER LA English DT Article AB Uncertainty analysis methods can be applied to numerical models of ground-water flow to estimate the relative importance of physical and hydrologic input variables with respect to ground-water travel time. Monte Carlo numerical simulations of unsaturated flow in the Calico Hills nonwelded zeolitic (CHnz) layer at Yucca Mountain, Nevada, indicate that variability in recharge, and to a lesser extent in matrix porosity, explains most of the variability in predictions of water travel time through the unsaturated zone. Variations in saturated hydraulic conductivity and unsaturated curve-fitting parameters were not statistically significant in explaining variability in water travel time through the unsaturated CHnz unit. The results of this study suggest that the large uncertainty associated with recharge rate estimates for the Yucca Mountain site is of concern because the performance of the potential repository would be more sensitive to uncertainty in recharge than to any other parameter evaluated. These results are not exhaustive because of the limited site characterization data available and because of the preliminary nature of this study, which is limited to a single stratigraphic unit, one dimension, and does not account for fracture flow or other potential fast pathways at Yucca Mountain. RP NICHOLS, WE (reprint author), PACIFIC NW LAB, DEPT GEOSCI, POB 999, MSIN K6-77, RICHLAND, WA 99352 USA. NR 14 TC 12 Z9 12 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0017-467X J9 GROUND WATER JI Ground Water PD MAR-APR PY 1993 VL 31 IS 2 BP 293 EP 301 DI 10.1111/j.1745-6584.1993.tb01821.x PG 9 WC Geosciences, Multidisciplinary; Water Resources SC Geology; Water Resources GA KP620 UT WOS:A1993KP62000014 ER PT J AU BEASLEY, TM CECIL, LD SHARMA, P KUBIK, PW FEHN, U MANN, LJ GOVE, HE AF BEASLEY, TM CECIL, LD SHARMA, P KUBIK, PW FEHN, U MANN, LJ GOVE, HE TI CL-36 IN THE SNAKE RIVER PLAIN AQUIFER AT THE IDAHO-NATIONAL-ENGINEERING-LABORATORY - ORIGIN AND IMPLICATIONS SO GROUND WATER LA English DT Article ID ACCELERATOR MASS-SPECTROMETRY; CL-36; STRIPA AB Between 1952 and 1984, low-level radioactive waste was introduced directly into the Snake River Plain aquifer at the Idaho National Engineering Laboratory (INEL), Idaho Falls, Idaho. These wastes were generated, principally, at the nuclear fuel reprocessing facility on the site. Our measurements of Cl-36 in monitoring and production well waters, downgradient from disposal wells and seepage ponds, found easily detectable, nonhazardous concentrations of this radionuclide from the point of injection to the INEL southern site boundary. Comparisons are made between H-3 and Cl-36 concentrations in aquifer water and the advantages of Cl-36 as a tracer of subsurface-water dynamics at the site are discussed. C1 IDAHO NATL ENGN LAB,USGS PROJECT OFF,IDAHO FALLS,ID 83401. UNIV ROCHESTER,NUCL STRUCT RES LAB,ROCHESTER,NY 14627. SWISS FED INST TECHNOL,PAUL SCHERRER INST,INST INTERMEDIATE PHYS,CH-8093 ZURICH,SWITZERLAND. RP BEASLEY, TM (reprint author), US DOE,ENVIRONM MEASUREMENTS LAB,376 HUDSON ST,NEW YORK,NY 10014, USA. NR 32 TC 13 Z9 15 U1 0 U2 0 PU GROUND WATER PUBLISHING CO PI WESTERVILLE PA 601 DEMPSEY RD, WESTERVILLE, OH 43081 SN 0017-467X J9 GROUND WATER JI Ground Water PD MAR-APR PY 1993 VL 31 IS 2 BP 302 EP 310 DI 10.1111/j.1745-6584.1993.tb01822.x PG 9 WC Geosciences, Multidisciplinary; Water Resources SC Geology; Water Resources GA KP620 UT WOS:A1993KP62000015 ER PT J AU HALL, SH AF HALL, SH TI SINGLE WELL TRACER TESTS IN AQUIFER CHARACTERIZATION SO GROUND WATER MONITORING AND REMEDIATION LA English DT Article AB When the purpose of aquifer testing is to yield data for modeling aqueous mass transport, pumping tests and gradient measurement can only partially satisfy characterization requirements. Effective porosity, ground water flow velocity, and the vertical distribution of hydraulic conductivity within the aquifer are left as unknowns. Single well tracer methods, when added to the testing program, can be used to estimate these parameters. A drift and pumpback test yields porosity and velocity, and point-dilution testing yields depth-discrete hydraulic information. A single emplacement of tracer into a test well is sufficient to conduct both tests. The tracer tests are facilitated by a simple method for injecting and evenly distributing the tracer solution into a wellbore, and by new ion-selective electrode instrumentation, specifically designed for submersible service, for monitoring the concentration of tracers such as bromide. RP HALL, SH (reprint author), PACIFIC NW LAB, CTR EARTH & ENVIRONM SCI, BOX 999, MSIN K6-96, RICHLAND, WA 99352 USA. NR 0 TC 11 Z9 12 U1 0 U2 9 PU GROUND WATER PUBLISHING CO PI WESTERVILLE PA 601 DEMPSEY RD, WESTERVILLE, OH 43081 SN 1069-3629 J9 GROUND WATER MONIT R JI Ground Water Monit. Remediat. PD SPR PY 1993 VL 13 IS 2 BP 118 EP 124 DI 10.1111/j.1745-6592.1993.tb00443.x PG 7 WC Water Resources SC Water Resources GA KZ632 UT WOS:A1993KZ63200008 ER PT J AU KNOBEL, LL MANN, LJ AF KNOBEL, LL MANN, LJ TI SAMPLING FOR PURGEABLE ORGANIC-COMPOUNDS USING POSITIVE-DISPLACEMENT PISTON AND CENTRIFUGAL SUBMERSIBLE PUMPS - A COMPARATIVE-STUDY SO GROUND WATER MONITORING AND REMEDIATION LA English DT Article AB Positive-displacement piston pumps that minimize sample agitation have no apparent advantage over centrifugal submersible pumps when used to collect ground water samples for analysis of low concentrations of purgeable organic compounds. Analytical uncertainties inherent in laboratory environments appear to influence analytical results of low-concentration purgeable organic compound samples more than either pump type or sampling team. Centrifugal submersible pumps are at least equally efficient as positive-displacement piston pumps in the recovery of carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene, and chloroform after sampling and analytical influences are made constant. RP KNOBEL, LL (reprint author), US GEOL SURVEY,INEL,MS 4148,POB 2230,IDAHO FALLS,ID 83403, USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU GROUND WATER PUBLISHING CO PI WESTERVILLE PA 601 DEMPSEY RD, WESTERVILLE, OH 43081 SN 1069-3629 J9 GROUND WATER MONIT R JI Ground Water Monit. Remediat. PD SPR PY 1993 VL 13 IS 2 BP 142 EP 148 DI 10.1111/j.1745-6592.1993.tb00446.x PG 7 WC Water Resources SC Water Resources GA KZ632 UT WOS:A1993KZ63200011 ER PT J AU VENKATADRI, R PETERS, RW AF VENKATADRI, R PETERS, RW TI CHEMICAL OXIDATION TECHNOLOGIES - ULTRAVIOLET-LIGHT HYDROGEN-PEROXIDE, FENTON REAGENT, AND TITANIUM DIOXIDE-ASSISTED PHOTOCATALYSIS SO HAZARDOUS WASTE & HAZARDOUS MATERIALS LA English DT Article AB The application status and potential of three chemical oxidation treatment methods which generate powerful oxidants (hydroxyl radicals): ultraviolet light (UV)/hydrogen peroxide (H2O2) process, Fenton's reagent treatment, and titanium dioxide (TiO2)-assisted photocatalytic degradation, are described and discussed. These oxidation methods are known to effectively degrade and, in several cases, mineralize contaminants ranging from inorganic compounds (such as cyanides) to chlorinated aliphatic compounds and complex aromatic compounds in reaction times on the order of a few minutes to a few hours. Of the three oxidation systems discussed, the technology for the UV/H2O2 process is the most advanced, with numerous successful full-scale treatment units already in existence. Applications of both the Fenton's reagent and TiO2-assisted photodegradation processes are currently being developed, with the concepts proven in numerous laboratory-scale studies for a wide range of contaminants. However, both of these processes have only been studied at the pilot/field scale to a limited extent. The application of Fenton's reagent as a pretreatment step prior to biological treatment for industrial wastes and contaminated soils appears promising. Improved system configuration and quantum efficiency of photoreactors are likely to improve the economics of TiO2-assisted photodegradation for groundwater treatment, especially with the use of solar illumination. RP VENKATADRI, R (reprint author), ARGONNE NATL LAB,DIV ENERGY SYST,9700 S CASS AVE,BLDG 362,ARGONNE,IL 60439, USA. NR 0 TC 225 Z9 230 U1 4 U2 41 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 SN 0882-5696 J9 HAZARD WASTE HAZARD JI Hazard. Waste Hazard. Mater. PD SPR PY 1993 VL 10 IS 2 BP 107 EP 149 DI 10.1089/hwm.1993.10.107 PG 43 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA LL384 UT WOS:A1993LL38400004 ER PT J AU HARRADINE, DM BUELOW, SJ DELLORCO, PC DYER, RB FOY, BR ROBINSON, JM SANCHEZ, JA SPONTARELLI, T WANDER, JD AF HARRADINE, DM BUELOW, SJ DELLORCO, PC DYER, RB FOY, BR ROBINSON, JM SANCHEZ, JA SPONTARELLI, T WANDER, JD TI OXIDATION CHEMISTRY OF ENERGETIC MATERIALS IN SUPERCRITICAL WATER SO HAZARDOUS WASTE & HAZARDOUS MATERIALS LA English DT Article AB The destruction of explosives and rocket fuel components by oxidation in supercritical water is described. The focus is on the major technical issues that must be resolved to make a disposal process practical. These issues include the chemistry of the process and methods for high-throughput processing of the target waste. The destruction efficiencies, the products of reaction contained in the reactor effluents, and methods for achieving high-throughput destruction of several representative explosives and propellant components are reported. C1 LOS ALAMOS NATL LAB,EXPLOS TECHNOL GRP,LOS ALAMOS,NM 87545. NR 0 TC 46 Z9 51 U1 0 U2 3 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 SN 0882-5696 J9 HAZARD WASTE HAZARD JI Hazard. Waste Hazard. Mater. PD SPR PY 1993 VL 10 IS 2 BP 233 EP 246 DI 10.1089/hwm.1993.10.233 PG 14 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA LL384 UT WOS:A1993LL38400011 ER PT J AU LEGGETT, RW ECKERMAN, KF WILLIAMS, LR AF LEGGETT, RW ECKERMAN, KF WILLIAMS, LR TI AN ELEMENTARY METHOD FOR IMPLEMENTING COMPLEX BIOKINETIC MODELS SO HEALTH PHYSICS LA English DT Article DE BIOKINETICS; COMPUTER CALCULATIONS; RECYCLING; INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION AB Recent efforts to incorporate greater anatomical and physiological realism into biokinetic models have resulted in many cases in mathematically complex formulations that limit routine application of the models. This paper describes an elementary, computer-efficient technique for implementing complex compartmental models, with attention focused primarily on biokinetic models involving time-dependent transfer ra.tes and recycling. The technique applies, in particular, to the physiologically based, age-specific biokinetic models recommended in Publication No. 56 of the International Commission on Radiological Protection, Age-Dependent Doses to Members of the Public from Intake of Radionuclides. C1 INDIANA UNIV, DEPT MATH & COMP SCI, S BEND, IN 46634 USA. RP LEGGETT, RW (reprint author), OAK RIDGE NATL LAB, DIV HLTH & SAFETY RES, METAB & DOSIMETRY RES GRP, OAK RIDGE, TN 37831 USA. NR 15 TC 16 Z9 17 U1 2 U2 4 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD MAR PY 1993 VL 64 IS 3 BP 260 EP 271 DI 10.1097/00004032-199303000-00004 PG 12 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 KN913 UT WOS:A1993KN91300004 PM 8432645 ER PT J AU MODERA, MP BONNEFOUS, Y AF MODERA, MP BONNEFOUS, Y TI STATISTICAL UNCERTAINTIES ASSOCIATED WITH MULTIPLEXED SAMPLING WITH A CONTINUOUS RADON MONITOR SO HEALTH PHYSICS LA English DT Article DE STATISTICS; SAMPLING; MONITORS, RADON; ALPHA PARTICLES AB One common type of continuous radon monitor is a flow-through device that counts alpha emissions from a gas sample as it passes through a scintillation cell. To improve the ability of this type of continuous radon monitor to track time-varying radon concentrations, a forward-marching data analysis procedure that considers the production, deposition, and decay of radon progeny as a function of time had been previously developed. This paper examines some of the statistical issues associated with using such a monitor and applying the forward-marching analysis procedure to the problem of multiplexed radon concentration samples. It uses Monte Carlo simulations, together with limited experimental data, to perform: 1) an examination of the potential bias of the forward-marching analysis technique; 2) an examination of a simplified methodology for evaluating concentration-measurement uncertainty for various radon concentration histories; and 3) an analysis of an example application of the simplified uncertainty analysis to multiplexing of soil-gas samples. The results of these analyses indicate: 1) that the forward-marching analysis technique is relatively unbiased, at least at concentrations >148 Bq m-3 for time steps longer than 120 s; 2) that a simplified uncertainty analysis procedure based upon Poisson statistics and no error correlation between intervals provides generally acceptable estimates of measurement uncertainty; and 3) that such a monitor and analysis technique can be successfully employed to measure multiplexed soil-gas samples, but is not appropriate for multiplexing of most building concentrations. RP MODERA, MP (reprint author), LAWRENCE BERKELEY LAB, INDOOR ENVIRONM PROGRAM, BERKELEY, CA 94720 USA. NR 9 TC 4 Z9 4 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD MAR PY 1993 VL 64 IS 3 BP 291 EP 299 DI 10.1097/00004032-199303000-00007 PG 9 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 KN913 UT WOS:A1993KN91300007 PM 8432647 ER PT J AU HUI, TE NICHOLS, LL OLSEN, PC MCDONALD, JC AF HUI, TE NICHOLS, LL OLSEN, PC MCDONALD, JC TI MEASUREMENT OF ACTIVITY IN ANTHROPOMORPHIC ORGAN PHANTOMS SO HEALTH PHYSICS LA English DT Article DE INTERNAL DOSE; BIOASSAY; RADIOACTIVITY; PHANTOMS AB This paper describes two nondestructive measurement techniques for determining the radioactivity in a homogeneous organ phantom with an acceptable error and the capability of being traceable to the National Institute of Standards and Technology. These two techniques are based on a method developed by Robley D. Evans in 1937 for measuring the amount of radium deposited in a living person. There are two significant improvements in the new techniques: 1) the radially-dependent error is eliminated, and 2) the effect of self absorption in the unknown body is measured and taken into account. The first assay method is a single-source technique involving four measurements and requiring only one standard source, the second one is a double-source technique involving six measurements and requiring two unequal standard sources. Three pairs of lung phantoms radiolabeled with Am-241, Cs-137, and Eu-154 were measured with both the single- and double-source techniques. The results imply that the self-attenuation of photons within the organ phantom cannot be neglected, especially at low energies. Finally, potential applications (other than the calibration of bioassay phantoms of the single- and double-source techniques) and their limitations are discussed. RP HUI, TE (reprint author), PACIFIC NW LAB, DEPT HLTH PHYS, POB 999, RICHLAND, WA 99352 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD MAR PY 1993 VL 64 IS 3 BP 311 EP 317 DI 10.1097/00004032-199303000-00010 PG 7 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 KN913 UT WOS:A1993KN91300010 PM 8432650 ER PT J AU THOMAS, RH AF THOMAS, RH TI CHALK RIVER BETA QUARTZ FIBER ELECTROSCOPE SO HEALTH PHYSICS LA English DT Letter RP THOMAS, RH (reprint author), UNIV CALIF BERKELEY, SCH PUBL HLTH, LAWRENCE LIVERMORE NATL LAB, BERKELEY, CA 94720 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD MAR PY 1993 VL 64 IS 3 BP 324 EP 324 PG 1 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 KN913 UT WOS:A1993KN91300019 PM 8432657 ER PT J AU MAHADEVAN, MS AMEMIYA, C JANSEN, G SABOURIN, L BAIRD, S NEVILLE, CE WORMSKAMP, N SEGERS, B BATZER, M LAMERDIN, J DEJONG, P WIERINGA, B KORNELUK, RG AF MAHADEVAN, MS AMEMIYA, C JANSEN, G SABOURIN, L BAIRD, S NEVILLE, CE WORMSKAMP, N SEGERS, B BATZER, M LAMERDIN, J DEJONG, P WIERINGA, B KORNELUK, RG TI STRUCTURE AND GENOMIC SEQUENCE OF THE MYOTONIC-DYSTROPHY (DM KINASE) GENE SO HUMAN MOLECULAR GENETICS LA English DT Article ID DNA-SEQUENCES AB The mutation causing myotonic dystrophy (DM) has recently been identified as an unstable CTG trinucleotide repeat located in the 3' untranslated region of a gene encoding for a protein with putative serine-threonine protein kinase activity. In this report we present the genomic sequences of the human and murine DM kinase gene. A comparison of these sequences with each other and with known cDNA sequences from both species, led us to predict a translation initiation codon, as well as determine the organization of the DM kinase gene. Several polymorphisms within the human DM kinase gene have been identified, and PCR assays to detect two of these are described. The complete sequence and characterization of the structure of the DM kinase gene, as well as the identification of novel polymorphisms within the gene, represent an important step in a further understanding of the genetics of myotonic dystrophy and the molecular biology of the gene. C1 UNIV OTTAWA,DEPT MICROBIOL & IMMUNOL,OTTAWA K1N 6N5,ONTARIO,CANADA. CHILDRENS HOSP EASTERN ONTARIO,DIV GENET,OTTAWA K1H 8L1,ONTARIO,CANADA. UNIV OTTAWA,DEPT PEDIAT,OTTAWA K1N 6N5,ONTARIO,CANADA. LAWRENCE LIVERMORE NATL LAB,CTR HUMAN GENOME,DIV BIOMED SCI,LIVERMORE,CA 94550. CATHOLIC UNIV NIJMEGEN,FAC MED SCI,DEPT CELL BIOL & HISTOL,6500 HB NIJMEGEN,NETHERLANDS. RI Wieringa, Berend/A-5346-2011 OI Wieringa, Berend/0000-0001-9192-8020 NR 20 TC 130 Z9 134 U1 0 U2 2 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0964-6906 J9 HUM MOL GENET JI Hum. Mol. Genet. PD MAR PY 1993 VL 2 IS 3 BP 299 EP 304 DI 10.1093/hmg/2.3.299 PG 6 WC Biochemistry & Molecular Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Genetics & Heredity GA KU137 UT WOS:A1993KU13700017 PM 8499920 ER PT J AU VEKLEROV, E AF VEKLEROV, E TI PROCESSING MEDICAL IMAGES SO IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE LA English DT Editorial Material RP VEKLEROV, E (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 0 TC 0 Z9 0 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 0739-5175 J9 IEEE ENG MED BIOL JI IEEE Eng. Med. Biol. Mag. PD MAR PY 1993 VL 12 IS 1 BP 25 EP 25 PG 1 WC Engineering, Biomedical; Medical Informatics SC Engineering; Medical Informatics GA KP211 UT WOS:A1993KP21100004 ER PT J AU LLACER, J ROMENY, BMT FLORACK, LMJ VIERGEVER, MA AF LLACER, J ROMENY, BMT FLORACK, LMJ VIERGEVER, MA TI REPRESENTATION OF MEDICAL IMAGES BY VISUAL RESPONSE FUNCTIONS SO IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE LA English DT Article ID SCALE-SPACE C1 UNIV UTRECHT HOSP,3511 GV UTRECHT,NETHERLANDS. RP LLACER, J (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. RI Viergever, Max/J-1215-2014 NR 16 TC 4 Z9 4 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 0739-5175 J9 IEEE ENG MED BIOL JI IEEE Eng. Med. Biol. Mag. PD MAR PY 1993 VL 12 IS 1 BP 40 EP 47 DI 10.1109/51.195939 PG 8 WC Engineering, Biomedical; Medical Informatics SC Engineering; Medical Informatics GA KP211 UT WOS:A1993KP21100006 ER PT J AU VEKLEROV, E AF VEKLEROV, E TI ON DECISION-MAKING IN TOMOGRAPHY SO IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE LA English DT Article RP VEKLEROV, E (reprint author), LAWRENCE BERKELEY LAB,DEPT COMP SYST ENGN,2 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 8 TC 0 Z9 0 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 0739-5175 J9 IEEE ENG MED BIOL JI IEEE Eng. Med. Biol. Mag. PD MAR PY 1993 VL 12 IS 1 BP 56 EP 61 DI 10.1109/51.195941 PG 6 WC Engineering, Biomedical; Medical Informatics SC Engineering; Medical Informatics GA KP211 UT WOS:A1993KP21100008 ER PT J AU VAWTER, GA HIETALA, VM KRAVITZ, SH AF VAWTER, GA HIETALA, VM KRAVITZ, SH TI DIGITAL OPTICAL-PHASE CONTROL IN RIDGE-WAVE-GUIDE PHASE MODULATORS SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article ID DEPLETION AB We report a new digital optical phase modulation concept based on depletion-edge-translation p-n junction GaAs/AlGaAs ridge-waveguide modulators. Digital modulation is achieved by integrating in series several discrete waveguide modulators with lengths related by successive factors of two. To illustrate the concept, we fabricated and demonstrated a three-bit digital phase modulator with 45-degrees resolution. This structure represents the first photonic integrated circuit that performs direct digital-electronic to analog-optical conversion. RP VAWTER, GA (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD MAR PY 1993 VL 5 IS 3 BP 313 EP 315 DI 10.1109/68.205622 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA KT470 UT WOS:A1993KT47000014 ER PT J AU Dell'Orco, D Scanlan, R Taylor, CE AF Dell'Orco, D. Scanlan, R. Taylor, C. E. TI DESIGN OF THE Nb3Sn DIPOLE D20 SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The design of a 50 mm bore superconducting Nb3Sn dipole with a short sample field of 13 Tat 4.3 K and a current of 5500 A/turn is presented. The magnet is composed by two double pancake layers. The inner cable has 37 strands with a strand diameter of 0.75 mm and a Cu/Sc ratio of 0.4; the outer cable has 47 strands with a diameter of 0.48 mm and a Cu/Sc ratio of 1.15. In order to obtain a high transfer function and low saturation effects on the multipoles, the stainless steel collar is elliptical and the iron yoke is "close in". The thin collar itself provides only a minimum prestress and the full prestress of 100 MPa is given by a 25 mm welded stainless steel shell or by winding a wire around the yoke. Aluminum spacers are used as assembly tools and as a means to control the gap size in the vertically split iron yoke. This paper presents the magnetic design and the calculated stress and strain distribution in structure and coils. A 1 m model called D20 is to be built and tested at LBL. C1 [Dell'Orco, D.; Scanlan, R.; Taylor, C. E.] Lawrence Berkeley Lab, 1 Cyclotron Rd M-S 46-161, Berkeley, CA 94720 USA. RP Dell'Orco, D (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd M-S 46-161, Berkeley, CA 94720 USA. FU Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U.S. Department of Energy [DE-AC03-76SF00098] FX This work was supported by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U.S. Department of Energy, under Contract No. DE-AC03-76SF00098. NR 9 TC 11 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 82 EP 86 DI 10.1109/77.233677 PN 2 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100005 ER PT J AU Smith, BA Marston, PG Minervini, JV Piek, ZS Vieira, R Pillsbury, RD Sullivan, JD Camille, RJ Titus, PH Stroynowski, R Bowers, J Deis, G House, A Johnson, C Ng, D Oberst, G Pedrotti, L Warren, R Wineman, S Yamamoto, R Harris, M Martovetsky, N Wisniewski, W AF Smith, B. A. Marston, P. G. Minervini, J. V. Piek, Z. S. Vieira, R. Pillsbury, R. D., Jr. Sullivan, J. D. Camille, R. J. Titus, P. H. Stroynowski, R. Bowers, J. Deis, G. House, A. Johnson, C. Ng, D. Oberst, G. Pedrotti, L. Warren, R. Wineman, S. Yamamoto, R. Harris, M. Martovetsky, N. Wisniewski, W. TI DESIGN CONCEPT FOR THE GEM DETECTOR MAGNET SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB A conceptual design is presented for the Superconducting Super Collider GEM detector solenoid magnet. The magnet has symmetric, independent vacuum vessel enclosed halves, each with a warm bore of 18 m and containing a superconducting solenoid coil. The coils use cable-in-conduit conductor with an aluminum sheath wound at a nominal 19 m diameter in a single layer against an aluminum bobbin. The overall length of the solenoid is 30 m. The operating current in the conductor is 50 kA, which generates a central field of 0.8 T and a stored energy of 2.5 GJ. Each half solenoid is comprised of 12 modules which are electrically joined with a low resistance joint and mechanically bolted together. The unique features of this magnet are the conductor design itself and the large coil diameter, which demands an on-site winding and assembly operation. The use of a natural convection thermosiphon loop for thermal radiation cooling eliminates plumbing complications associated with double-jacketed cable-in-conduit conductors. Locating the aluminum sheath outside the conduit for quench protection enables optimizing the copper-to-superconductor ratio inside the conduit for stability alone. The conceptual design for the magnet, including the design for the detector dependent magnetics, the superconducting coils and coil. structure (cold mass), the coil winding process, the vacuum vessel and liquid nitrogen shields, the cold mass supports and the magnet assembly procedure are described. C1 [Smith, B. A.; Marston, P. G.; Minervini, J. V.; Piek, Z. S.; Vieira, R.; Pillsbury, R. D., Jr.; Sullivan, J. D.; Camille, R. J.] MIT, Ctr Plasma Fus, Cambridge, MA 02139 USA. [Stroynowski, R.] So Methodist Univ, Dallas, TX 75275 USA. [Bowers, J.; Deis, G.; House, A.; Johnson, C.; Ng, D.; Oberst, G.; Pedrotti, L.; Warren, R.; Wineman, S.; Yamamoto, R.] Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Smith, BA (reprint author), MIT, Ctr Plasma Fus, Cambridge, MA 02139 USA. FU Superconducting Super Collider Laboratory [SSC-92-W-17751] FX Work supported by Superconducting Super Collider Laboratory under Contract Number SSC-92-W-17751. NR 0 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 87 EP 92 DI 10.1109/77.233678 PN 2 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100006 ER PT J AU Green, MA AF Green, Michael A. CA STAR Collaboration TI A LARGE SUPERCONDUCTING THIN SOLENOID FOR THE STAR EXPERIMENT AT RHIC SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB This Report describes the 4.4 meter, warm bore diameter, thin superconducting solenoid, for the proposed STAR experiment at the Brookhaven National Laboratory. The STAR solenoid will generate a very uniform central magnetic induction of 0.5 T within a space which is 4.0 meters in diameter by 4.2 meters long. The solenoid and its cryostat will be 0.7 radiation lengths thick over a length of 5.45 meters, about the center of the magnet, making it the largest solenoid less than one radiation length to be built. This report describes a proposed design for the solenoid and cryostat, its flux return iron, its cryogenic system and its power supply and quench protection system. C1 [Green, Michael A.; STAR Collaboration] Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Green, MA (reprint author), Lawrence Berkeley Lab, Berkeley, CA 94720 USA. FU Office of High Energy and Nuclear Physics, Nuclear Sciences Division, US Department of Energy [DE-AC03-76SF00098] FX This work was supported by the Office of High Energy and Nuclear Physics, Nuclear Sciences Division, US Department of Energy, under contract number DE-AC03-76SF00098. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 104 EP 106 DI 10.1109/77.233491 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100008 ER PT J AU Cha, YS Hull, JR Choi, US AF Cha, Y. S. Hull, J. R. Choi, U. S. TI CRYOSTABILIZATION OF HIGH-TEMPERATURE SUPERCONDUCTING MAGNETS WITH SUBCOOLED FLOW IN MICROCHANNELS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Subcooled flow of liquid nitrogen in microchannels is proposed as a means to enhance the stability of superconducting magnets. Analysis shows that high current density or a low stabilizer fraction can be obtained in a cryostable magnet. Increase in stability (with the Stekley criterion as a measure) is directly related to coolant velocity and coolant channel aspect ratio; however, it is accompanied by a corresponding increase in pressure drop of the system. In addition, the coolant temperature rises as a function of coolant residence time and coolant-to-conductor ratio. C1 [Cha, Y. S.; Hull, J. R.; Choi, U. S.] Argonne Natl Lab, Div Mat & Components Technol, Argonne, IL 60439 USA. RP Cha, YS (reprint author), Argonne Natl Lab, Div Mat & Components Technol, Argonne, IL 60439 USA. FU U.S. Department of Energy, Conservation and Renewable Energy [W-31-109-Eng-38] FX This work has been sponsored by the U.S. Department of Energy, Conservation and Renewable Energy, as part of a program to develop electric power technology, under Contract W-31-109-Eng-38. NR 16 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 172 EP 176 DI 10.1109/77.233698 PN 2 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100026 ER PT J AU Schoenung, SM Bieri, RL Meier, WR Bickel, TC AF Schoenung, S. M. Bieri, R. L. Meier, W. R. Bickel, T. C. TI Cost Savings and Prospects for Applications of Micro Superconducting Magnetic Energy Storage (SMES) Using High Temperature Superconductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Recently, interest in superconducting magnetic energy storage (SMES) systems of approximately 1 MJ storage capacity has grown among potential industry and utility users. Today's product is relatively expensive. Potential savings, especially in the capital cost of the refrigerator component, could result from the incorporation of high temperature superconductors (HTS). This paper presents configuration estimates for 1 MJ HTS-SMES systems, along with an assessment of possible cost savings over a similar system using conventional superconductors. C1 [Schoenung, S. M.; Bieri, R. L.; Meier, W. R.] WJ Schafer Associates, 303 Lindbergh Ave, Livermore, CA 94550 USA. [Bickel, T. C.] Sandia Natl Lab, Div 6221, Albuquerque, NM 87185 USA. RP Schoenung, SM (reprint author), WJ Schafer Associates, 303 Lindbergh Ave, Livermore, CA 94550 USA. FU Sandia National Laboratories [96-2233] FX Support for this work was provided by Sandia National Laboratories under Contract No. 96-2233. NR 12 TC 7 Z9 7 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 200 EP 203 DI 10.1109/77.233705 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100033 ER PT J AU Schoenung, SM Meier, WR Hull, JR Fagaly, RL Heiberger, M Stephens, RB Leuer, JA Guzman, RA AF Schoenung, S. M. Meier, W. R. Hull, J. R. Fagaly, R. L. Heiberger, M. Stephens, R. B. Leuer, J. A. Guzman, R. A. TI DESIGN ASPECTS OF MID-SIZE SMES USING HIGH TEMPERATURE SUPERCONDUCTORS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Conceptual designs of modular, cold-supported SMES units using high temperature superconductors (HTS) have been investigated over the mid-size energy range of 2 to 200 MWh (7.2 to 720 GJ). This size range covers many utility, industrial, and military applications. Both toroidal and solenoidal configurations were analyzed to determine physical dimensions, heat loads and cost of major components. Among the effects considered were the impact of critical current density on feasible configurations, mass of conductor, and cost; the effects of magnetic field and strain limits on physical parameters and structural mass; and the savings in refrigeration from operating at higher temperature. The design of the HTS conductor, stability criteria, and coolant selection are also discussed. C1 [Schoenung, S. M.; Meier, W. R.] WJ Schafer Associates Inc, Livermore, CA USA. [Hull, J. R.] Argonne Natl Lab, Chicago, IL USA. [Fagaly, R. L.; Heiberger, M.; Stephens, R. B.; Leuer, J. A.; Guzman, R. A.] Gen Atom Co, San Diego, CA USA. RP Schoenung, SM (reprint author), WJ Schafer Associates Inc, Livermore, CA USA. OI Stephens, Richard/0000-0002-7034-6141 FU U.S. Department of Energy FX Research supported by the U.S. Department of Energy. NR 13 TC 1 Z9 1 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 234 EP 237 DI 10.1109/77.233714 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100042 ER PT J AU Lue, JW Dresner, L Schwenterly, SW Wilson, CT Lubell, MS AF Lue, J. W. Dresner, L. Schwenterly, S. W. Wilson, C. T. Lubell, M. S. TI INVESTIGATING THERMAL HYDRAULIC QUENCHBACK IN A CABLE-IN-CONDUIT SUPERCONDUCTOR SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Quench propagation of a cable-in-conduit force cooled superconductor plays a very important role in the protection of a magnet built with such a conductor as in a Superconducting Magnetic Energy Storage (SMES) system. Some thermal analysis showed that the compressional and frictional heating exerted by the expanding hot helium could heat the helium away from the normal zone above the superconductor current sharing temperature. Thus an acceleration of the quench propagation could be realized. This phenomenon was termed thermal hydraulic quench back (THQ). A setup has been built specifically to investigate this phenomenon. The test sample consists of a 50-m-long NbTi superconducting cable enclosed in a stainless steel conduit. Heaters 0.2 to 8 m long are provided to quench the conductor. This paper reports experimental finding of THQ and its dependence on the initial normal zone length, the conductor current, the magnetic field, and the coolant temperature. C1 [Lue, J. W.; Dresner, L.; Schwenterly, S. W.; Wilson, C. T.; Lubell, M. S.] Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. RP Lue, JW (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. FU Defense Nuclear Agency under Martin Marietta Energy Systems, Inc. [0046C082A1]; U.S. Department of Energy [DE-AC05-84OR21400] FX Research sponsored by the Defense Nuclear Agency under Interagency Agreement No. 0046C082A1 under Martin Marietta Energy Systems, Inc., contract DE-AC05-84OR21400 with the U.S. Department of Energy. NR 3 TC 3 Z9 3 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 338 EP 341 DI 10.1109/77.233474 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100067 ER PT J AU Brown, TG Lang, DD Mueller, J Schultz, J AF Brown, T. G. Lang, D. D. Mueller, J. Schultz, J. TI THE CONFIGURATION DEVELOPMENT OF THE SUPERCONDUCTING MAGNETS FOR THE SSAT-S TOKAMAK DEVICE SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The Steady State Advanced Tokamak (SSAT) device will be developed to demonstrate steady state tokamak operations and optimize plasma conditions in a steady-state environment. Superconducting toroidal field (TF) and poloidal field (PF) coils are planned, as they are well suited for the long-pulse, high-duty-factor operation of the SSAT mission. A two coil TF module forms the basis of the tokamak core. PF coils, consisting of a solenoid and 6 ring-coils surround the TF coils. This paper describes the configurational development of the SSAT device to meet the physics objectives and subsystem design requirements. The physics requirement of low field ripple and sufficient plasma access for tangential neutral beams influenced the configuration in determining the size and number of TF coils. Further configuration influences included low activation considerations, divertor pumping, service line access, requirements for remote maintenance and compatibility with the existing TFTR test cell facility. C1 [Brown, T. G.; Mueller, J.] Grumman Corp, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. [Lang, D. D.] Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. [Schultz, J.] MIT, Cambridge, MA 02139 USA. RP Brown, TG (reprint author), Grumman Corp, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. FU U.S. DoE [DE-ACO2-76-CHO-3073] FX Work Supported by U.S. DoE Contract No. DE-ACO2-76-CHO-3073 NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 350 EP 356 DI 10.1109/77.233472 PN 2 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100069 ER PT J AU Bruzzone, P Mitchell, N Katheder, H Salpietro, E Chaplin, MR Shen, SS Slack, DS Rauch, J Brehm, W Ceresara, S Ricci, M Oliva, AB AF Bruzzone, P. Mitchell, N. Katheder, H. Salpietro, E. Chaplin, M. R. Shen, S. S. Slack, D. S. Rauch, J. Brehm, W. Ceresara, S. Ricci, M. Oliva, A. Bonito TI TEST RESULT OF FULL SIZE 40 KA NET/ITER CONDUCTOR IN THE FENIX TEST FACILITY SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Three Nb3Sn cable-in-conduit prototype conductors have been manufactured in the frame of the European conductor development programme for NET. They have been tested in the FENIX test facility beyond their operating conditions (current up to 40 kA, magnetic field up to 13.5 T, supercritical Helium up to 8 K). The testing procedure is described and the test results are discussed. The main object of the test is the measurement of temperature margin under DC operation and the hydraulic pressure drop. C1 [Bruzzone, P.; Mitchell, N.; Katheder, H.; Salpietro, E.] Max Planck Inst Plasmaphys, Net Team, Boltzmannstr 2, D-8046 Garching, Germany. [Chaplin, M. R.; Shen, S. S.; Slack, D. S.] Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. [Rauch, J.; Brehm, W.] ASEA Brown Boveri, Oerlikon Works, CH-8050 Zurich, Switzerland. [Ceresara, S.] Europa Met LMI, I-55052 Fornaci Di Barga, LU, Italy. [Ricci, M.] ENEA Lab Supercondutt, I-00044 Frascati, Italy. [Oliva, A. Bonito] Ansaldo Componenti, I-16152 Genoa, Italy. RP Bruzzone, P (reprint author), Max Planck Inst Plasmaphys, Net Team, Boltzmannstr 2, D-8046 Garching, Germany. NR 14 TC 9 Z9 9 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 357 EP 360 DI 10.1109/77.233471 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100070 ER PT J AU Niemann, RC Cha, YS Hull, JR AF Niemann, R. C. Cha, Y. S. Hull, J. R. TI PERFORMANCE MEASUREMENTS OF SUPERCONDUCTING CURRENT LEADS WITH LOW HELIUM BOIL-OFF RATES SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB A performance-measurement facility for current leads has been developed as a part of Argonne National Laboratory's program to develop applications for high-temperature superconductors. The facility measures the rate of helium vapor boil-off due to current-lead heat input to liquid helium and the pressure drop across a current lead for a pair of leads operating at currents up to 100 A. The facility's major components are a liquid-helium dewar with low background-heat input; a dewar insert that incorporates the current leads and associated instrumentation or connections for flow, pressure, level, temperature and voltage measurements; and a computer driven data-acquisition system. Background heat input is low enough so that boil-off rates one-tenth that of an optimized conventional lead can be characterized. The facility has been operated with conventional (i.e., vapor-cooled copper) leads, and with leads incorporating high-temperature superconductors at their cold ends. Details of the facility design, construction, and operating experience are presented. C1 [Niemann, R. C.; Cha, Y. S.; Hull, J. R.] Argonne Natl Lab, Div Mat & Components Technol, Bldg 335,9700 South Cass Ave, Argonne, IL 60439 USA. RP Niemann, RC (reprint author), Argonne Natl Lab, Div Mat & Components Technol, Bldg 335,9700 South Cass Ave, Argonne, IL 60439 USA. FU U.S. Department of Energy, Conservation and Renewable Energy [W-31-109-Eng-38] FX Work supported by the U.S. Department of Energy, Conservation and Renewable Energy, as part of a program to develop electric power technology, under Contract W-31-109-Eng-38. NR 5 TC 8 Z9 8 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 392 EP 395 DI 10.1109/77.233727 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100079 ER PT J AU Shu, QS Demko, J Dorman, R Finan, D Hatfield, D Syromyatnikov, I Zolotov, A Mazur, P Peterson, T AF Shu, Q. S. Demko, J. Dorman, R. Finan, D. Hatfield, D. Syromyatnikov, I. Zolotov, A. Mazur, P. Peterson, T. TI THERMAL OPTIMUM ANALYSES AND MECHANICAL DESIGN OF 10-kA, VAPOR-COOLED POWER LEADS FOR SSC SUPERCONDUCTING MAGNET TESTS AT MTL SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The spiral-fin, 10-kA, helium vapor-cooled power leads have been designed for Superconducting Super Collider superconducting magnet tests at the Magnet Test Laboratory. In order to thermally optimize the parameters of the power leads, the lead diameters which minimize the Carnot work for several different lengths, two different fin geometries, and two RRR values of the lead materials were determined. The cryogenic refrigeration and liquefaction loads for supporting the leads have also been calculated. The optimum operational condition with different currents is discussed. An improved mechanical design of the 10-kA power leads was undertaken, with careful consideration of the cryogenic and mechanical performance. In the design, a new thermal barrier device to reduce heat conduction from the vacuum and gas seal area was employed. Therefore, the electric insulation assembly, which isolates the ground potential parts of the lead from the high-power parts, was moved into a warm region in order to prevent vacuum and helium leakage in the O-ring seals due to transient cold temperature. The instrumentation for testing the power leads is also discussed. C1 [Shu, Q. S.; Demko, J.; Dorman, R.; Finan, D.; Hatfield, D.; Syromyatnikov, I.; Zolotov, A.] Superconducting Super Collider Lab, Dallas, TX 75237 USA. [Mazur, P.; Peterson, T.] Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Shu, QS (reprint author), Superconducting Super Collider Lab, Dallas, TX 75237 USA. NR 11 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 408 EP 412 DI 10.1109/77.233735 PN 2 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100083 ER PT J AU van Oort, JM Scanlan, RM Weijers, HW Wessel, S ten Kate, HHJ AF van Oort, J. M. Scanlan, R. M. Weijers, H. W. Wessel, S. ten Kate, H. H. J. TI THE REDUCTION OF THE CRITICAL CURRENT IN Nb3Sn CABLES UNDER TRANSVERSE LOADS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The degradation of the critical current of impregnated Rutherford type Nb3Sn cables is investigated as a function of the applied transverse load and magnetic field. The cable is made of TWCA modified jelly-roll type strand material and has a keystone angle of 1.0 degree. The voltage-current characteristics are determined for the magnetic field ranging from 2 to 11 tesla and transverse pressure up to 250 MPa on the cable surface. It is found that the 48-strand cable, made of strands with 6 elements in the matrix, shows a larger critical current degradation than the 26-strand cable with 36 elements per strand. The global degradation of the 48-strand cable is 63% at 150 MPa, and 40% at 150 MPa for the 26-strand cable. Micro-analysis of the cross-section shows permanent damage to the sharp edge of the cable. The influence of the keystone angle on the critical-current degradation is currently under investigation. C1 [van Oort, J. M.; Scanlan, R. M.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Accelerator & Fus Res, Superconducting Magnet Grp, 1 Cyclotron Rd, Berkeley, CA 94720 USA. [Weijers, H. W.; Wessel, S.; ten Kate, H. H. J.] Univ Twente, Ctr Appl Superconduct, NL-7500 AE Enschede, Netherlands. RP van Oort, JM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Accelerator & Fus Res, Superconducting Magnet Grp, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U.S. Department of Energy [DE-AC03-76SF0098] FX This work was supported by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U.S. Department of Energy, under contact No. DE-AC03-76SF0098. NR 12 TC 10 Z9 10 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 559 EP 562 DI 10.1109/77.233767 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100120 ER PT J AU Green, MA AF Green, Michael A. TI REDUCED MASS PERSISTENT SWITCHES FOR LARGE SUPERCONDUCTING MAGNETS IN SPACE SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Superconducting magnets in space must operate in the persistent mode. This paper describes the characteristics of low mass niobium titanium persistent switches for low mass superconducting magnets which are designed to quench protect themselves through the quench back process. (The whole coil is driven normal shortly after the quench has started and the magnet stored energy is taken up by the coil and the persistent switch.) The concept of using a resistor and diode in parallel with the persistent switch to reduce the overall mass of the persistent switch system and the helium consumption during magnet charging is discussed in the report. A 1.4 meter diameter free-flyer version of the 11.6 MJ stored energy ASTROMAG magnet and its persistent switch is presented as an example [1]. C1 [Green, Michael A.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Green, MA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. FU office of Astrophysics of NASA; Office of Basic Energy Science, United States Department of Energy under the Lawrence Berkeley Laboratory [DE-AC03-76SF00098] FX This work was supported by the office of Astrophysics of NASA and the Office of Basic Energy Science, United States Department of Energy under the Lawrence Berkeley Laboratory contract number DE-AC03-76SF00098. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 582 EP 585 DI 10.1109/77.233772 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100126 ER PT J AU Mclnturff, AD Augustynowicz, S Burgett, W Coombes, R Dickey, C Dombeck, T Feitz, W Flora, R Gannon, J Haenni, D Kraushaar, P Levin, M McAshan, M Mulholland, G Murray, D Robinson, W Savord, T Spinos, F Tool, G Weisend, J Wallis, D Voy, D Zbasnik, J AF Mclnturff, A. D. Augustynowicz, S. Burgett, W. Coombes, R. Dickey, C. Dombeck, T. Feitz, W. Flora, R. Gannon, J. Haenni, D. Kraushaar, P. Levin, M. McAshan, M. Mulholland, G. Murray, D. Robinson, W. Savord, T. Spinos, F. Tool, G. Weisend, J., II Wallis, D. Voy, D. Zbasnik, J. TI HALF CELL OPERATIONS TESTS OF THE SUPERCONDUCTING SUPER COLLIDER LABORATORY SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Preparations and tests are underway at the N-15 site in Waxahachie, Texas to obtain operational parameters and characteristics for 100 meter long 50mm aperture half cell of the SSCL collider. The first power phase of this test refers to the Accelerator System String Test (ASST). This represents a project milestone. These measurements are being added to the previous information obtained during the thousands of hours operating the 40mm aperture half cell minus quadrupole string. These data are being compared to each other and to various computer models to obtain optimum operating scenarios for the final collider components and their use. The last run on the previous string emphasized the mid-cell spool "SPR" components; i.e., bypass leads, recooler, cool down valve, quench valve, etc., and their operation. Problems previously reported and their proposed solutions or proven fixes are discussed. Future tests with the present half cell and possible plans for its expansion to a full cell plus are presented. Heat loads from previous runs are compared with their design values. C1 [Mclnturff, A. D.; Augustynowicz, S.; Burgett, W.; Coombes, R.; Dombeck, T.; Feitz, W.; Gannon, J.; Haenni, D.; Kraushaar, P.; Levin, M.; McAshan, M.; Mulholland, G.; Murray, D.; Robinson, W.; Savord, T.; Spinos, F.; Tool, G.; Weisend, J., II; Wallis, D.; Voy, D.; Zbasnik, J.] Superconducting Super Collider Lab, 2550 Beckleymeade Ave, Dallas, TX 75237 USA. [Flora, R.] Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Mclnturff, AD (reprint author), Superconducting Super Collider Lab, 2550 Beckleymeade Ave, Dallas, TX 75237 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 622 EP 628 PN 2 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100134 ER PT J AU Lietzke, AF Barak, P Benjegerdes, R Caspi, S Cortella, J Dell'Orco, D Gilbert, W Green, MI Mirk, K Peters, C Scanlan, R Taylor, CE Wandesforde, A AF Lietzke, A. F. Barak, P. Benjegerdes, R. Caspi, S. Cortella, J. Dell'Orco, D. Gilbert, W. Green, M. I. Mirk, K. Peters, C. Scanlan, R. Taylor, C. E. Wandesforde, A. TI QUADRUPOLE MAGNETS FOR THE SSC SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB At LBL, we have designed, constructed, and tested four short (1m) models and six full-size (5m) models of the Superconducting Super Collider (SSC) main-ring 5 meter focusing quadrupole magnet (211 Tesla/meter). The results of this program are herein summarized. C1 [Lietzke, A. F.; Barak, P.; Benjegerdes, R.; Caspi, S.; Cortella, J.; Dell'Orco, D.; Gilbert, W.; Green, M. I.; Mirk, K.; Peters, C.; Scanlan, R.; Taylor, C. E.; Wandesforde, A.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RP Lietzke, AF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U.S. Department of Energy [DE-AC03-76SF00098] FX Work supported by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U.S. Department of Energy, under Contract No. DE-AC03-76SF00098. NR 7 TC 0 Z9 0 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 629 EP 636 DI 10.1109/77.233782 PN 2 PG 8 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100135 ER PT J AU Dell'Orco, D Caspi, S O'Neill, J Lietzke, A Scanlan, R Taylor, CE Wandesforde, A AF Dell'Orco, D. Caspi, S. O'Neill, J. Lietzke, A. Scanlan, R. Taylor, C. E. Wandesforde, A. TI A 50 mm BORE SUPERCONDUCTING DIPOLE WITH A UNIQUE IRON YOKE STRUCTURE SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB A 50 mm bore superconducting dipole with a thin stainless steel collar and a close in elliptical iron yoke was designed in order to obtain a high transfer function and low saturation effects on the multipoles, and a one meter model was built and tested. Training behavior of the first 1 m model, called D19, is presented at 4.3 K and 1.8 K. At 1.8 K it reached the record field of 10.06 T. The two layer cos theta winding uses 30 and 36 strand cables identical to the cables of the 50 mm bore SSC dipole and it has an operating field of 6.6 T at 4.35 K with a current of 5800 A. To evaluate behavior at high fields, the mechanical structure for the model was designed for 10 T. The thin collar itself provides only a minimum prestress of 10 MPa, and the full prestress of 70 MPa is given by the iron yoke. An aluminum spacer is used to control the gap size in the vertically split iron yoke. The tapered gap in the yoke is determined by the size of the Al spacer so that during cooldown there is no loss of coil prestress and the gap remains closed when the magnet is energized. C1 [Dell'Orco, D.; Caspi, S.; O'Neill, J.; Lietzke, A.; Scanlan, R.; Taylor, C. E.; Wandesforde, A.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd MS 46-161, Berkeley, CA 94720 USA. RP Dell'Orco, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd MS 46-161, Berkeley, CA 94720 USA. FU Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U.S. Department of Energy [DE-AC03-76SF00098] FX This work was supported by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U.S. Department of Energy, under Contract No. DE-AC03-76SF00098. NR 8 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 637 EP 641 DI 10.1109/77.233783 PN 2 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100136 ER PT J AU Gibson, CR Bliss, DW Simon, RE Jain, AK Wanderer, P AF Gibson, C. R. Bliss, D. W. Simon, R. E. Jain, A. K. Wanderer, P. TI LOCATING THE MAGNETIC CENTER OF THE SSC CDM USING A TEMPORARY QUADRUPOLE HELD SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The SSC dipole magnets must be very accurately aligned for the accelerator to work correctly. To align the magnets one must accurately know the center of the magnetic field. However, locating the center is difficult because of the extreme uniformity of the dipole field. A technique has been developed to determine the magnetic center of the SSC dipole magnet under ambient test conditions. This technique involves flowing current in the upper half of the coils in the direction opposite to the current in the lower half. This is done using a temporary lead connected to the splice joining the two coil halves and two matched power supplies. The resulting field is primarily skew quadrupole and has high field gradients which allow the center to be accurately located. The viability of this method has been verified by analysis using Taylor series expansion of the resulting magnetic field. Analysis has also verified that off-the-shelf power supplies have low enough mismatch to be used in this technique. The analytical results have been verified through the test of a short dipole magnet at the Brookhaven National Laboratory. C1 [Gibson, C. R.; Bliss, D. W.; Simon, R. E.] Gen Dynam Space Syst Div, San Diego, CA 92186 USA. [Jain, A. K.; Wanderer, P.] Brookhaven Natl Lab, Upton, NY 11973 USA. RP Gibson, CR (reprint author), Gen Dynam Space Syst Div, San Diego, CA 92186 USA. FU Superconducting Super Collider project FX The work described herein is being accomplished under contract to the Universities Research Association in support of the Superconducting Super Collider project for the U.S. Department of Energy. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 646 EP 649 DI 10.1109/77.233785 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100138 ER PT J AU Nah, W Akhmetov, A Anerella, M Bossert, R Bush, T Capone, DW Carson, J Coombes, R Cottingham, J Delchamps, SW Devred, A DiMarco, J Ganetis, G Garber, M Goodzeit, C Ghosh, A Gourlay, S Greene, A Gupta, R Hanft, R Jain, A Kahn, S Kelly, E Koska, W Kuchnir, M Kuzminski, J Lamm, MJ Mantsch, P Mazur, PO Morgan, G Muratore, J Ogitsu, T Orris, D Ozelis, J Peterson, T Pewitt, EG Prodell, A Puglisi, M Radusewicz, P Rehak, M Rohrer, EP Royet, J Sampson, W Sanger, P Scanlan, R Schermer, R Shutt, R Stiening, R Strait, J Taylor, C Thomas, R Thompson, P Tompkins, JC Turner, J Wake, M Wanderer, P Willen, E Yu, Y Zbasnik, J Zhao, Y Zheng, H AF Nah, W. Akhmetov, A. Anerella, M. Bossert, R. Bush, T. Capone, D. W., II Carson, J. Coombes, R. Cottingham, J. Delchamps, S. W. Devred, A. DiMarco, J. Ganetis, G. Garber, M. Goodzeit, C. Ghosh, A. Gourlay, S. Greene, A. Gupta, R. Hanft, R. Jain, A. Kahn, S. Kelly, E. Koska, W. Kuchnir, M. Kuzminski, J. Lamm, M. J. Mantsch, P. Mazur, P. O. Morgan, G. Muratore, J. Ogitsu, T. Orris, D. Ozelis, J. Peterson, T. Pewitt, E. G. Prodell, A. Puglisi, M. Radusewicz, P. Rehak, M. Rohrer, E. P. Royet, J. Sampson, W. Sanger, P. Scanlan, R. Schermer, R. Shutt, R. Stiening, R. Strait, J. Taylor, C. Thomas, R. Thompson, P. Tompkins, J. C. Turner, J. Wake, M. Wanderer, P. Willen, E. Yu, Y. Zbasnik, J. Zhao, Y. Zheng, H. TI Quench Characteristics of 5-cm-Aperture, 15-m-Long SSC Dipole Magnet Prototypes SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The quench performance and ramp rate sensitivity of eighteen 5-cm-aperture, 15-m-long SSC dipole magnet prototypes are discussed. All the magnets appear to reach a quench plateau near their extrapolated short sample current limit and well in excess of the operating current with very little training. Most of the magnets, however, exhibit a dramatic degradation of their quench current as a function of ramp rate, which for the most part, can be attributed to large cable eddy currents. C1 [Nah, W.; Akhmetov, A.; Bush, T.; Capone, D. W., II; Coombes, R.; Devred, A.; DiMarco, J.; Goodzeit, C.; Kuzminski, J.; Ogitsu, T.; Puglisi, M.; Radusewicz, P.; Sanger, P.; Schermer, R.; Tompkins, J. C.; Turner, J.; Wake, M.; Yu, Y.; Zbasnik, J.; Zhao, Y.; Zheng, H.] Superconducting Super Collider Lab, Dallas, TX 75237 USA. [Anerella, M.; Cottingham, J.; Ganetis, G.; Garber, M.; Ghosh, A.; Greene, A.; Gupta, R.; Jain, A.; Kahn, S.; Kelly, E.; Morgan, G.; Muratore, J.; Prodell, A.; Rehak, M.; Rohrer, E. P.; Sampson, W.; Shutt, R.; Thomas, R.; Thompson, P.; Wanderer, P.; Willen, E.] Brookhaven Natl Lab, Upton, NY 11973 USA. [Bossert, R.; Carson, J.; Delchamps, S. W.; Gourlay, S.; Hanft, R.; Koska, W.; Kuchnir, M.; Lamm, M. J.; Mantsch, P.; Mazur, P. O.; Orris, D.; Ozelis, J.; Peterson, T.; Pewitt, E. G.; Strait, J.] Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. [Ogitsu, T.; Wake, M.] Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. [Nah, W.] Korea Electrotechnol Res Inst, Chang Won 641120, Kyongnam, South Korea. [Royet, J.; Scanlan, R.; Taylor, C.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Nah, W (reprint author), Superconducting Super Collider Lab, Dallas, TX 75237 USA. OI Mantsch, Paul/0000-0002-8382-7745 FU U.S. Department of Energy [DE-AC35-89ER40486] FX This work is supplied by the U.S. Department of Energy under contract No. DE-AC35-89ER40486. Manuscript received August 24, 1992. NR 6 TC 7 Z9 7 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 658 EP 661 DI 10.1109/77.233787 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100141 ER PT J AU Jaffery, TS Carson, J Delchamps, SW Kinney, W Koska, W Lamm, MJ Ozelis, JP Strait, J Wake, M AF Jaffery, T. S. Carson, J. Delchamps, S. W. Kinney, W. Koska, W. Lamm, M. J. Ozelis, J. P. Strait, J. Wake, M. TI TEST RESULTS OF POST-ASST DESIGN FERMILAB BUILT 1.5 METER, SSC COLLIDER MODEL DIPOLE MAGNETS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB A series of 1.5 meter long and 50 mm aperture model SSC collider dipole magnets have been successfully built and tested at Fermilab. Later models have been built to test several extensions to the Fermilab design and variations in the manufacturing parameters. Some of the variations tested included conductor insulation scheme, alternate materials for coil end parts and coil winding. The coils are instrumented with voltage taps for the purposes of quench localization and with strain gages to measure the stresses and deflections in the coil and magnets support structure. Data from the quench performance, coil stress, end force and harmonics are presented and compared with design expectations and correlated with changes in the magnet design and assembly methods. C1 [Jaffery, T. S.; Carson, J.; Delchamps, S. W.; Kinney, W.; Koska, W.; Lamm, M. J.; Ozelis, J. P.; Strait, J.; Wake, M.] Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. RP Jaffery, TS (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. FU U.S. Department of Energy FX Work Supported by the U.S. Department of Energy. NR 8 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 666 EP 669 DI 10.1109/77.233792 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100143 ER PT J AU Zhao, Y Akhmetov, A Anerella, M Bossert, R Bush, T Capone, DW Carson, J Coombes, R Cottingham, J Delchamps, SW Devred, A DiMarco, J Ganetis, G Garber, M Goodzeit, C Ghosh, A Gourlay, S Greene, A Gupta, R Hanft, R Jain, A Kahn, S Kelly, E Koska, W Kuchnir, M Kuzminski, J Lamm, MJ Mantsch, P Mazur, PO Morgan, G Muratore, J Nah, W Ogitsu, T Orris, D Ozelis, J Peterson, T Pewitt, EG Prodell, A Puglisi, M Radusewicz, P Rehak, M Rohrer, EP Royet, J Sampson, W Sanger, P Scanlan, R Schermer, R Shutt, R Stiening, R Strait, J Taylor, C Thomas, R Thompson, P Tompkins, JC Turner, J Wake, M Wanderer, P Willen, E Yu, Y Zbasnik, J Zheng, H AF Zhao, Y. Akhmetov, A. Anerella, M. Bossert, R. Bush, T. Capone, D. W., II Carson, J. Coombes, R. Cottingham, J. Delchamps, S. W. Devred, A. DiMarco, J. Ganetis, G. Garber, M. Goodzeit, C. Ghosh, A. Gourlay, S. Greene, A. Gupta, R. Hanft, R. Jain, A. Kahn, S. Kelly, E. Koska, W. Kuchnir, M. Kuzminski, J. Lamm, M. J. Mantsch, P. Mazur, P. O. Morgan, G. Muratore, J. Nah, W. Ogitsu, T. Orris, D. Ozelis, J. Peterson, T. Pewitt, E. G. Prodell, A. Puglisi, M. Radusewicz, P. Rehak, M. Rohrer, E. P. Royet, J. Sampson, W. Sanger, P. Scanlan, R. Schermer, R. Shutt, R. Stiening, R. Strait, J. Taylor, C. Thomas, R. Thompson, P. Tompkins, J. C. Turner, J. Wake, M. Wanderer, P. Willen, E. Yu, Y. Zbasnik, J. Zheng, H. TI Current Dependence of Harmonic Field Coefficients of 5-cm-Aperture, 15-m-Long SSC Dipole Magnet Prototypes SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Eighteen 5-cm-aperture, 15-m-long SSC dipole magnet prototypes have been produced and cold tested. On each prototype, the dependence of harmonic field coefficients on magnet current was measured as part of a study of the magnetic field quality. For most of the magnets, the observed behavior conforms to what can be expected from the effects of persistent magnetization currents and iron yoke saturation. A few prototypes, however, exhibited anomalies during current ramp at 4 A/s which can be attributed to large cable eddy currents. C1 [Zhao, Y.; Akhmetov, A.; Bush, T.; Capone, D. W., II; Coombes, R.; Devred, A.; DiMarco, J.; Goodzeit, C.; Kuzminski, J.; Nah, W.; Ogitsu, T.; Puglisi, M.; Radusewicz, P.; Sanger, P.; Schermer, R.; Stiening, R.; Tompkins, J. C.; Turner, J.; Wake, M.; Yu, Y.; Zbasnik, J.; Zheng, H.] Superconducting Super Collider Lab, Dallas, TX 75237 USA. [Anerella, M.; Cottingham, J.; Ganetis, G.; Garber, M.; Ghosh, A.; Greene, A.; Gupta, R.; Jain, A.; Kahn, S.; Kelly, E.; Morgan, G.; Muratore, J.; Prodell, A.; Rehak, M.; Rohrer, E. P.; Sampson, W.; Shutt, R.; Thomas, R.; Thompson, P.; Wanderer, P.; Willen, E.] Brookhaven Natl Lab, Upton, NY 11973 USA. [Bossert, R.; Carson, J.; Delchamps, S. W.; Gourlay, S.; Hanft, R.; Koska, W.; Kuchnir, M.; Lamm, M. J.; Mantsch, P.; Mazur, P. O.; Orris, D.; Ozelis, J.; Peterson, T.; Pewitt, E. G.; Strait, J.] Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. [Nah, W.; Ogitsu, T.; Wake, M.] Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. Korea Electrotechnol Res Inst, Chang Won 641120, Kyongnam, South Korea. [Royet, J.; Scanlan, R.; Taylor, C.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Zhao, Y (reprint author), Superconducting Super Collider Lab, Dallas, TX 75237 USA. OI Mantsch, Paul/0000-0002-8382-7745 FU U.S. Department of Energy [DE-AC35-89ER40486] FX This work is supported by the U.S. Department of Energy under Contract No. DE-AC35-89ER40486. NR 9 TC 4 Z9 4 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 674 EP 677 DI 10.1109/77.233794 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100145 ER PT J AU Ozelis, JP Delchamps, S Gourlay, S Jaffery, T Kinney, W Koska, W Kuchnir, M Lamm, MJ Mazur, PO Orris, D Strait, J Wake, M Dimarco, J Kuzminski, J Zheng, H AF Ozelis, J. P. Delchamps, S. Gourlay, S. Jaffery, T. Kinney, W. Koska, W. Kuchnir, M. Lamm, M. J. Mazur, P. O. Orris, D. Strait, J. Wake, M. Dimarco, J. Kuzminski, J. Zheng, H. TI AC Loss Measurements of Model and Full Size 50mm SSC Collider Dipole Magnets at Fermilab SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Tests have recently been performed at Fermilab in order to measure the energy losses due to eddy currents and iron and superconductor magnetization. These measurements were performed on six 1.5m long model magnets and eight 15m long full scale collider dipole magnets. AC losses were measured as a function of ramp rate using sawtooth ramps from 500 to 5000 Amps for both types of magnets, while bipolar studies were additionally performed on some of the short magnets. The measured magnet voltage and current for a complete cycle are digitally integrated to yield the energy loss per cycle. Measurement reproducibility is typically 5%, with good agreement between long magnet measurements and extrapolations from short magnet measurement results. Magnetization loss measurements among similar magnet types agree to within experimental error, while eddy current losses correlate strongly with the observed dependence of quench current on ramp rate. C1 [Ozelis, J. P.; Delchamps, S.; Gourlay, S.; Jaffery, T.; Kinney, W.; Koska, W.; Kuchnir, M.; Lamm, M. J.; Mazur, P. O.; Orris, D.; Strait, J.; Wake, M.] Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. [Dimarco, J.; Kuzminski, J.; Zheng, H.] SSC Lab, Dallas, TX 75237 USA. RP Ozelis, JP (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. FU U.S. Department of Energy FX Work supported by U.S. Department of Energy NR 9 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 678 EP 681 DI 10.1109/77.233795 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100146 ER PT J AU Ogitsu, T Akhmetov, A Anerella, M Bossert, R Bush, T Capone, DW Carson, J Coombes, R Cottingham, J Delchamps, SW Devred, A DiMarco, J Ganetis, G Garber, M Goodzeit, C Ghosh, A Gourlay, S Greene, A Gupta, R Hanft, R Jain, A Kahn, S Kelly, E Koska, W Kuchnir, M Kuzminski, J Lamm, MJ Mantsch, P Mazur, PO Morgan, G Muratore, J Nah, W Orris, D Ozelis, J Peterson, T Pewitt, EG Prodell, A Puglisi, M Radusewicz, P Rehak, M Rohrer, EP Royet, J Sampson, W Sanger, P Scanlan, R Schermer, R Shutt, R Stiening, R Strait, J Taylor, C Thomas, R Thompson, P Tompkins, JC Tumer, J Wake, M Wanderer, P Willen, E Yu, Y Zbasnik, J Zhao, Y Zheng, H AF Ogitsu, T. Akhmetov, A. Anerella, M. Bossert, R. Bush, T. Capone, D. W., II Carson, J. Coombes, R. Cottingham, J. Delchamps, S. W. Devred, A. DiMarco, J. Ganetis, G. Garber, M. Goodzeit, C. Ghosh, A. Gourlay, S. Greene, A. Gupta, R. Hanft, R. Jain, A. Kahn, S. Kelly, E. Koska, W. Kuchnir, M. Kuzminski, J. Lamm, M. J. Mantsch, P. Mazur, P. O. Morgan, G. Muratore, J. Nah, W. Orris, D. Ozelis, J. Peterson, T. Pewitt, E. G. Prodell, A. Puglisi, M. Radusewicz, P. Rehak, M. Rohrer, E. P. Royet, J. Sampson, W. Sanger, P. Scanlan, R. Schermer, R. Shutt, R. Stiening, R. Strait, J. Taylor, C. Thomas, R. Thompson, P. Tompkins, J. C. Tumer, J. Wake, M. Wanderer, P. Willen, E. Yu, Y. Zbasnik, J. Zhao, Y. Zheng, H. TI MECHANICAL PERFORMANCE OF 5-CM-APERTURE, 15-M-LONG SSC DIPOLE MAGNET PROTOTYPES SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB This paper summarizes the mechanical performance of the most recent 5-cm-aperture, 15-m-long SSC dipole magnet prototypes. The magnets were produced at Brookhaven National Laboratory (BNL) and Fermi National Accelerator Laboratory (FNAL) under contract with the Superconducting Super Collider Laboratory (SSCL). The BNL magnets rely on an horizontally-split yoke with collared ends, while the FNAL magnets rely on a vertically-split yoke with collet-style end clamps. Magnets of both designs are equipped with strain gauges enabling us to measure the azimuthal pressures exerted by the coils against the collar poles as well as the axial forces transmitted from the coil ends to the end plates. A comparison of the mechanical behaviors measured by the strain gauges is presented. We also discuss how the behavior of the 5-cm-aper-ture magnets compare to that of the 4-cm-aperture prototypes. C1 [Ogitsu, T.; Akhmetov, A.; Bush, T.; Capone, D. W., II; Coombes, R.; Devred, A.; DiMarco, J.; Goodzeit, C.; Kuzminski, J.; Nah, W.; Puglisi, M.; Radusewicz, P.; Sanger, P.; Schermer, R.; Stiening, R.; Tompkins, J. C.; Tumer, J.; Wake, M.; Yu, Y.; Zbasnik, J.; Zhao, Y.; Zheng, H.] Superconducting Super Collider Lab, Dallas, TX 75237 USA. [Anerella, M.; Cottingham, J.; DiMarco, J.; Ganetis, G.; Ghosh, A.; Greene, A.; Gupta, R.; Jain, A.; Kahn, S.; Kelly, E.; Morgan, G.; Muratore, J.; Prodell, A.; Rehak, M.; Rohrer, E. P.; Sampson, W.; Shutt, R.; Thomas, R.; Thompson, P.; Wanderer, P.; Willen, E.] Brookhaven Natl Lab, Upton, NY 11973 USA. [Bossert, R.; Carson, J.; Delchamps, S. W.; Gourlay, S.; Hanft, R.; Koska, W.; Kuchnir, M.; Lamm, M. J.; Mantsch, P.; Mazur, P. O.; Orris, D.; Ozelis, J.; Peterson, T.; Pewitt, E. G.; Strait, J.] Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. [Ogitsu, T.; Wake, M.] Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. [Nah, W.] Korea Electrotechnol Res Inst, Chang Won 641120, Kyongnam, South Korea. [Royet, J.; Scanlan, R.; Taylor, C.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Ogitsu, T (reprint author), Superconducting Super Collider Lab, Dallas, TX 75237 USA. OI Mantsch, Paul/0000-0002-8382-7745 FU U.S. Department of Energy [DE-AC35-89ER40486] FX This work is supported by the U.S. Department of Energy under Contract No. DE-AC35-89ER40486. NR 12 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 686 EP 691 DI 10.1109/77.233797 PN 2 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100148 ER PT J AU Kuchnir, M Bleadon, M Delchamps, SW Schmidt, E Bossert, R Carson, J Gourlay, S Hanft, R Koska, W Lamm, MJ Mazur, PO Orris, D Ozelis, J Strait, J Wake, M Devred, A DiMarco, J Kuzminski, J Ogitsu, T Yu, Y Zheng, H AF Kuchnir, M. Bleadon, M. Delchamps, S. W. Schmidt, E. Bossert, R. Carson, J. Gourlay, S. Hanft, R. Koska, W. Lamm, M. J. Mazur, P. O. Orris, D. Ozelis, J. Strait, J. Wake, M. Devred, A. DiMarco, J. Kuzminski, J. Ogitsu, T. Yu, Y. Zheng, H. TI MAGNETIC FIELD ANGLE CHANGES DURING MANUFACTURE AND TESTING OF SSC COLLIDER DIPOLES SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Measurements of the magnetic field angle along the length of collider dipole magnets are discussed. These superconducting magnets were built at Fermilab for the Superconducting Super Collider (SSC) by Fermilab and General Dynamics personnel. These measurements were made at four stages in the assembly and test sequence. The data show that changes can occur both during installation in the cryostat and as a result of cold testing. Most of the changes during installation are correlated with the welding of the tie bar restraints. But the changes observed as a result of the cold testing can be attributed to changes in the magnetization of the iron laminations. C1 [Kuchnir, M.; Bleadon, M.; Delchamps, S. W.; Schmidt, E.; Bossert, R.; Carson, J.; Gourlay, S.; Hanft, R.; Koska, W.; Lamm, M. J.; Mazur, P. O.; Orris, D.; Ozelis, J.; Strait, J.; Wake, M.] Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. [Devred, A.; DiMarco, J.; Kuzminski, J.; Ogitsu, T.; Yu, Y.; Zheng, H.] SSC Lab, Dallas, TX USA. RP Kuchnir, M (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. FU U.S. Department of Energy FX Work Supported by U.S. Department of Energy NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 696 EP 698 DI 10.1109/77.233799 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100150 ER PT J AU Cortella, JM Devred, A Wandesforde, A AF Cortella, J. M. Devred, A. Wandesforde, A. TI MECHANICAL PERFORMANCE OF FULL-SCALE PROTOTYPE QUADRUPOLE MAGNETS FOR THE SSC SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Six 5-m-long prototype quadrupole magnets have been built and cold-tested at Lawrence Berkeley Laboratory for the Superconducting Super Collider. Each of the magnets contained instrumentation to monitor the mechanical performance of the magnets during assembly and cold-testing. In addition, the instrumentation was used along with physical measurements as aids during magnet assembly. Quantities measured include coil pressures during assembly, cooldown, and magnet energization; axial thermal contraction of the magnets during cooldown; and axial force transmitted to the magnet end-plates. For the most part, mechanical measurements have proven repeatable and agree well with analysis. C1 [Cortella, J. M.; Wandesforde, A.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. [Devred, A.] SSC Lab, Dallas, TX 75237 USA. RP Cortella, JM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU U.S. Department of Energy [DE-AC35-89ER40486] FX This work was supported by the U.S. Department of Energy, under contract No. DE-AC35-89ER40486 NR 8 TC 0 Z9 0 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 699 EP 704 DI 10.1109/77.233800 PN 2 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100151 ER PT J AU Seuntjens, JM Clark, FY Headley, TJ Geulich, FA Yang, NYC AF Seuntjens, J. M. Clark, F. Y. Headley, T. J. Geulich, F. A. Yang, N. Y. C. TI IMAGE ANALYSIS OF SUPERCONDUCTING COMPOSITES SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Image analysis of multifilament superconducting materials can yield quantitative analysis of many critical parameters that affect conductor performance. The SSC Laboratory has image analysis capabilities over the range of 0.5 X to 10,000 X. Transmission Electron Microscopy (TEM) analysis equipped with the same image analysis system at Sandia National Laboratory extends these capabilities to over 150,000 X. Among the analyses routines for composite materials are the local area ratio (LAR), barrier volume fraction, barrier inside perimeter, barrier outside perimeter, barrier thickness, filament roundness, filament area, filament perimeter, transmission Xray negative analysis, and feature position analysis. TEM work also provides analyses of alpha-phase titanium precipitate volume fraction, precipitate thickness, and precipitate spacing. The techniques for analysis are described in this paper and examples of each of the techniques applied to samples from the SSCL vendor qualification program (VQP) are presented. C1 [Seuntjens, J. M.; Clark, F. Y.] SSC Lab, MS 1005, Dallas, TX 75237 USA. [Headley, T. J.; Geulich, F. A.] Sandia Natl Labs, Div 1822, Albuquerque, NM 87185 USA. [Yang, N. Y. C.] Sandia Natl Labs, Div 8714, Livermore, CA 94551 USA. RP Seuntjens, JM (reprint author), SSC Lab, MS 1005, Dallas, TX 75237 USA. FU Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U. S. Department of Energy [DE-AC02-89ER40486] FX Supported by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U. S. Department of Energy, under contract no. DE-AC02-89ER40486. Manuscript received August 24, 1992. NR 6 TC 1 Z9 1 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 729 EP 733 DI 10.1109/77.233807 PN 2 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100158 ER PT J AU Lamm, MJ Butteris, J Coulter, K Hess, C Lewis, D Jaffery, T Kinney, W McInturff, AD Ozelis, JP Strait, J AF Lamm, M. J. Butteris, J. Coulter, K. Hess, C. Lewis, D. Jaffery, T. Kinney, W. McInturff, A. D. Ozelis, J. P. Strait, J. TI A FACILITY TO TEST SHORT SUPERCONDUCTING ACCELERATOR MAGNETS AT FERMILAB SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB During the past four years the Superconducting Magnet R&D facility at Fermilab (Lab 2) has successfully tested superconducting dipole, quadrupole, and correction coil magnets less than 2 meters in length for the SSC project and the Tevatron D0/B0 Low-P Insertion. During this time several improvements have been made to the facility that have greatly enhanced its magnet testing capabilities. Among the upgrades have been a new rotating coil and data acquisition system for measuring magnetic fields, a controlled flow liquid helium transfer line using an electronically actuated cryo valve, and stand-alone systems for measuring AC loss and training low current Tevatron correction coil packages. A description of the Lab 2 facilities is presented. C1 [Lamm, M. J.; Butteris, J.; Coulter, K.; Hess, C.; Lewis, D.; Jaffery, T.; Kinney, W.; McInturff, A. D.; Ozelis, J. P.; Strait, J.] Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. RP Lamm, MJ (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. FU Department of Energy FX Work Supported by the Department of Energy. NR 4 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 740 EP 743 DI 10.1109/77.233810 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100161 ER PT J AU Leung, EMW Albert, GA Agarwal, KL Madura, DD Silva, DJ Sharma, SK Murphy, JB Heese, R Kalsi, S AF Leung, E. M. W. Albert, G. A. Agarwal, K. L. Madura, D. D. Silva, D. J. Sharma, S. K. Murphy, J. B. Heese, R. Kalsi, S. TI SUPERCONDUCTING X-RAY LITHOGRAPHY 180 BENDING DIPOLE MAGNET DESIGN AND MATERIAL SELECTION SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The Superconducting X-Ray Lithography. Source (SXLS) being built at Brookhaven National Laboratory [1] requires two superconducting bending magnets. This machine is an electron synchrotron whose application is to produce synchrotron x-ray radiation that is utilized in a lithographic process producing computer chips. Each of the magnets serves a combined purpose of focusing and bending. The magnet is an air core design with a warm, removable beam tube. This system is unusual and challenging due to the limited space and stringent magnetic field uniformity requirement. The latter dictates very careful selection of structural material at 4.2 K and at the beam injection field of 1 T. The process in which we went through to select the coldmass structure material, high strength structural bolts, weld rods for the structural welds and various components within the cryomagnetic system is described. Results of the verification testings will be described. A brief summary of the final design is also presented. C1 [Leung, E. M. W.; Albert, G. A.; Agarwal, K. L.; Madura, D. D.; Silva, D. J.] Gen Dynam Space Syst Div, MZ C1-8260,POB 85990, San Diego, CA 92186 USA. [Sharma, S. K.; Murphy, J. B.; Heese, R.] Brookhaven Natl Lab, Upton, NY 11973 USA. [Kalsi, S.] Grumman Aerosp Corp, Bethpage, NY USA. RP Leung, EMW (reprint author), Gen Dynam Space Syst Div, MZ C1-8260,POB 85990, San Diego, CA 92186 USA. FU U.S. Department of Defense Defense Advanced Research Projects Agency (DARPA) FX This work was supported by the U.S. Department of Defense Defense Advanced Research Projects Agency (DARPA). NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 825 EP 828 DI 10.1109/77.233831 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100182 ER PT J AU Madura, DD Leung, EM Nguyen, LV Gurol, H Murphy, JB Sharma, SK AF Madura, D. D. Leung, E. M. Nguyen, L. V. Gurol, H. Murphy, J. B. Sharma, S. K. TI SUPERCONDUCTING X-RAY LITHOGRAPHY 180 degrees BENDING DIPOLE MAGNETICS ANALYSIS METHODOLOGY SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The Superconducting X-Ray Lithography Source (SXLS) being built at Brookhaven National Laboratory and described in another paper at this conference, requires two superconducting bending magnets. These are combined function magnets in the sense that they are required to provide specific nonzero multipole magnetic field components. The system requirements for magnetic field quality are challenging. The magnetic field calculational approach and verification are presented here. To verify the satisfaction of requirements, field calculations to 7 significant digits were necessary. The effects of magnetic permeability of magnet materials, eddy currents, superconductor magnetization, current leads, splices, structural deflection and manufacturing tolerances were calculated in addition to the current density field calculations. C1 [Madura, D. D.; Leung, E. M.; Nguyen, L. V.; Gurol, H.] Gen Dynam Space Syst Div, MZ C1-8260,POB 85990, San Diego, CA 92186 USA. [Murphy, J. B.; Sharma, S. K.] Brookhaven Natl Lab, Upton, NY 11973 USA. RP Madura, DD (reprint author), Gen Dynam Space Syst Div, MZ C1-8260,POB 85990, San Diego, CA 92186 USA. FU Defense Advanced Research Projects Agency (DARPA) [20-89446] FX This work was supported by the Defense Advanced Research Projects Agency (DARPA) under contract number 20-89446. We wish to thank the following people for their technical contributions to this work: Hank Hsieh and Roy Blumberg of Brookhaven National Laboratory, Michael Reusch and Swarn Kalsi of Grumman Aerospace Corporation and John Dalessandro of General Dynamics. We would also like to acknowledge and thank Vector Fields for their support of the three dimensional transient model. M. A. Green of Lawrence Berkeley Laboratory and G. Morgan of Brookhaven National Laboratory also assisted us in modeling superconductor magnetization. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 829 EP 832 DI 10.1109/77.233832 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100183 ER PT J AU Scanlan, RM AF Scanlan, R. M. TI The Evolution of Tooling, Techniques, and Quality Control for Accelerator Dipole Magnet Cables SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The present generation of particle accelerators are utilizing the flattened, compacted, single layer cable design introduced nearly 20 years ago at Rutherford Laboratory. However, the requirements for current density, filament size, dimensional control, long lengths, and low current degradation are much more stringent for the present accelerators compared with the earlier Tevatron and HERA accelerators. Also, in order to achieve higher field strengths with efficient use of superconductor, the new designs require wider cables with more strands. These requirements have stimulated an active research effort which has led to significant improvements in critical current density and conductor manufacturing. In addition they have stimulated the development of new cabling techniques, improved tooling, and better measurement techniques. The need to produce over 20 million meters of cable has led to the development of high speed cabling machines and on-line quality assurance measurements. These new developments will be discussed, and areas still requiring improvement will be identified. C1 [Scanlan, R. M.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RP Scanlan, RM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU Office of Energy Research, Office of High Energy and Nuclear Physics, Division of High Energy Physics of the U.S. Department of Energy [DE-AC03-76SF00098] FX This work was supported by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, Division of High Energy Physics of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098. NR 29 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 842 EP 849 DI 10.1109/77.233834 PN 2 PG 8 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100185 ER PT J AU Seuntjens, JM Bardos, VA Christopherson, D Capone, DW Clark, FY Coleman, ES Erdmann, MJ Headley, TJ Jones, B Levy, V Washburn, DK AF Seuntjens, J. M. Bardos, V. A. Christopherson, D. Capone, D. W., II Clark, F. Y. Coleman, E. S. Erdmann, M. J. Headley, T. J. Jones, B. Levy, V. Washburn, D. K. TI ANALYSIS OF MONOFILAMENT AND MULTIFILAMENT SAMPLES OBTAINED FROM PHASE I OF THE SSCL VENDOR QUALIFICATION PROGRAM SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article C1 [Seuntjens, J. M.; Bardos, V. A.; Christopherson, D.; Capone, D. W., II; Clark, F. Y.; Coleman, E. S.; Erdmann, M. J.; Jones, B.; Levy, V.; Washburn, D. K.] SSC Lab, MS 1005, Dallas, TX 75237 USA. [Headley, T. J.] Sandia Natl Labs, Div 1822, Albuquerque, NM 87185 USA. RP Seuntjens, JM (reprint author), SSC Lab, MS 1005, Dallas, TX 75237 USA. FU Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U. S. Department of Energy [DE-AC02-89ER40486] FX Supported by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, High Energy Physics Division, U. S. Department of Energy, under contract no. DE-AC02-89ER40486. NR 5 TC 0 Z9 0 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 850 EP 854 DI 10.1109/77.233835 PN 2 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100186 ER PT J AU Coffey, HT AF Coffey, Howard T. TI US MAGLEV: STATUS AND OPPORTUNITIES SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Recognizing the development of maglev systems in Germany and Japan, and the growing congestion, air pollution and energy consumption resulting from our current transportation system, the United States, in 1990, embarked on a program to evaluate the potential usefulness of these systems in the U.S. In this paper, the utility of maglev systems in alleviating some of these problems, progress in the current program, and opportunities for participation by the superconductivity and cryogenic communities are discussed. C1 [Coffey, Howard T.] Argonne Natl Lab, Ctr Transportat Res, 9700 S Cass Ave, Argonne, IL 60439 USA. RP Coffey, HT (reprint author), Argonne Natl Lab, Ctr Transportat Res, 9700 S Cass Ave, Argonne, IL 60439 USA. FU Federal Railroad Administration [DTFR 53-91-X-00018]; U.S. Dept of Energy FX Work supported by the Federal Railroad Administration through interagency agreement DTFR 53-91-X-00018 with the U.S. Dept of Energy. NR 6 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 863 EP 868 DI 10.1109/77.233838 PN 2 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100189 ER PT J AU Hull, JR AF Hull, John R. TI HIGH-TEMPERATURE SUPERCONDUCTING CURRENT LEADS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Use of high-temperature superconductors (HTSs) for current leads to deliver power to devices at liquid helium temperature, now near commercial realization, has the potential to reduce refrigeration requirements and helium boil-off to values significantly lower than the theoretically best values achievable with conventional leads. Considerable advantage is achieved by operating these leads with an intermediate-temperature heat sink. The HTS part of the lead can be made from pressed and sintered powder. Powder-in-tube fabrication is also possible, but the normal metal part of the lead acts as a thermal short and cannot provide much stabilization without increasing the refrigeration requirement. For lead stability, designs with low current density are favored. Such leads can be manufactured with today's technology, and refrigeration requirements are lower for the same allowable burnout time. Higher current densities result in lower boil-off for the same lead length, but burnout times can be very short. In comparing experiment to theory in open systems, the density of helium vapor must be accounted for in calculating the expected boil-off. For very-low-loss leads, two-dimensional heat transfer and the state of the dewar near the leads may play dominant roles in lead performance. C1 [Hull, John R.] Argonne Natl Lab, Mat & Components Technol Div, 9700 S Cass Ave, Argonne, IL 60439 USA. RP Hull, JR (reprint author), Argonne Natl Lab, Mat & Components Technol Div, 9700 S Cass Ave, Argonne, IL 60439 USA. FU U.S. Department of Energy, Conservation and Renewable Energy [W-31-109-Eng-38] FX This work was supported by the U.S. Department of Energy, Conservation and Renewable Energy, as part of a program to develop electric power technology, under Contract W-31-109-Eng-38. The author gratefully acknowledges technical discussions with R. C. Niemann, Y. S. Cha, M. A. Green, J. L. Wu, G. Morrow, D. Hazelton, M.-C. Chyu, A. Unal, and S.-Y. Seol. NR 25 TC 39 Z9 39 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 869 EP 875 DI 10.1109/77.233839 PN 2 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TG UT WOS:000209703100190 ER PT J AU Shibutani, K Egi, T Hayashi, S Fukumoto, Y Shigaki, I Masuda, Y Ogawa, R Kawate, Y AF Shibutani, K. Egi, T. Hayashi, S. Fukumoto, Y. Shigaki, I. Masuda, Y. Ogawa, R. Kawate, Y. TI FABRICATION OF SUPERCONDUCTING JOINTS FOR Bi-2212 PANCAKE COILS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB To evaluate the possibility of persistent current operation for NMR/MRI using a Bi-2212 oxide superconductor at 4.2K, the temperature dependence of magnetic relaxation for the Bi-2212 single crystal have been measured. It was found that the operating current must be one-fourth of Jc at 4.2K in order to satisfy the stability condition for NMR/MRI operation (Delta J/J less than 0.005 ppm/hour). In order to establish the fabrication process of long wire, fabrication of superconducting coil made of a Bi-2212 silver sheathed wire was carried out by means of partial melt growth process. We have succeeded in generating 1.60T an the external magnetic field of 0T at 4.2K. This coil employed silver-sheathed Bi-2212 tape which was 100 mu m thick, 10mm wide and 150m long. We also have attempted to fabricate superconducting jointed pancake coils, the critical current reaching 80A in the external magnetic field of 1.0T at 4.2K. C1 [Shibutani, K.; Egi, T.; Hayashi, S.; Fukumoto, Y.; Shigaki, I.; Masuda, Y.; Ogawa, R.; Kawate, Y.] Kobe Steel Ltd, Superconducting & Cryogen Technol Ctr, Kobe, Hyogo 65122, Japan. RP Shibutani, K (reprint author), Brookhaven Natl Lab, Div Mat Sci, Dr M Suenaga,Bldg 480, Long Isl City, NY 11973 USA. NR 9 TC 21 Z9 21 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 935 EP 938 DI 10.1109/77.233849 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200005 ER PT J AU Schwenterly, SW Lue, JW Lubell, MS Luton, JN Joshi, CH AF Schwenterly, S. W. Lue, J. W. Lubell, M. S. Luton, J. N. Joshi, C. H. TI CRITICAL CURRENT MEASUREMENTS ON Ag/Bi-Pb-Sr-Ca-Cu-O COMPOSITE COILS AS A FUNCTION OF TEMPERATURE AND EXTERNAL MAGNETIC FIELD SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Transport critical currents have been measured on two coils of high-temperature superconducting (HTSC) tape as a function of temperature and external magnetic field. The HTSC tape and the coils were fabricated by American Superconductor Corporation. The sample coil windings have inside and outside diameters of roughly 25 nun and 40 mm, respectively, and a length of 50 mm. They contain about 300 turns of filamentary Bi-Pb-Sr-Ca-Cu-O 2223 HTSC material sheathed in Ag to form a 0.18-mm by 2.54-mm tape, with a total length of about 30 m. Critical current results are reported for temperatures between 4.2 K and 90 K, in magnetic fields ranging up to 5.5 T. C1 [Schwenterly, S. W.; Lue, J. W.; Lubell, M. S.; Luton, J. N.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. [Joshi, C. H.] Amer Superconductor Corp, Watertown, MA 02172 USA. RP Schwenterly, SW (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. FU ORNL High Temperature Superconductivity Pilot Center FX The financial support of the ORNL High Temperature Superconductivity Pilot Center is gratefully acknowledged. The authors would also like to thank C.T. Wilson of ORNL for his help in setting up and operating the data acquisition system, and D. Waldman and T. Francavilla of the two Naval research facilities mentioned above for their corroborative measurements on Coil 2. NR 9 TC 4 Z9 4 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 949 EP 952 DI 10.1109/77.233853 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200009 ER PT J AU Luo, JS Merchant, N Escorcia-Aparicio, E Maroni, VA Gruen, DM Tani, BS Riley, GN Carter, WL AF Luo, J. S. Merchant, N. Escorcia-Aparicio, E. Maroni, V. A. Gruen, D. M. Tani, B. S. Riley, G. N., Jr. Carter, W. L. TI PHASE CHEMISTRY AND MICROSTRUCTURE EVOLUTION IN SILVER-CLAD (Bi2-xPbx)Sr2Ca2Cu3Oy WIRES SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The reaction kinetics and mechanism that control the conversion of (Bi,Pb)(2)Sr(2)CaCu(2)Oz (Bi-2212) + alkaline earth cuprates to (Bi,Pb)(2)Sr(2)Ca(2)Cu3O(y) (Bi-2223) in silver -clad wires were investigated as a function of equilibration temperature and time at a fixed oxygen partial pressure (7.5% O-2). Measured values for the fractional conversion of Bi-2223 versus time were evaluated based on the Avrami equation. SEM studies of partially and fully converted wires suggest that (1) the transformation to Bi-2223 is two-dimensional and controlled by a diffusion process, (2) liquid phases are present during part of the Bi-2212 -> Bi-2223 conversion, and (3) growth of the (Sr,Ca)(14)Cu(2)4O(41) phase accompanies Bi-2223 formation. C1 [Luo, J. S.; Merchant, N.; Escorcia-Aparicio, E.; Maroni, V. A.; Gruen, D. M.; Tani, B. S.] Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. [Riley, G. N., Jr.; Carter, W. L.] Amer Superconductor Corp, Watertown, MA 02172 USA. RP Luo, JS (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. FU U. S. Department of Energy, Conservation and Renewable Energy, as a part of a DOE program to develop electric power technology [W-31-109-ENG-38] FX The authors wish to acknowledge the support and encouragement of Drs. R. B. Poeppel and A. Malozemoff. One of the authors (E. E-A) is grateful to the Argonne National laboratory, Division of Education Programs for partial support during a student appointment. The work at Argonne National Laboratory was sponsored by the U. S. Department of Energy, Conservation and Renewable Energy, as a part of a DOE program to develop electric power technology, under Contract W-31-109-ENG-38. NR 12 TC 35 Z9 36 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 972 EP 975 DI 10.1109/77.233859 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200015 ER PT J AU Shi, DL Sengupta, S Smith, M Wang, Z Biondo, AC Balachandran, U Goretta, KC AF Shi, Donglu Sengupta, S. Smith, M. Wang, Z. Biondo, A. C. Balachandran, U. Goretta, K. C. TI FLUX PINNING BY 211 PRECIPITATES IN MELT-PROCESSED YBa2Cu3Ox SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Magnetic hysteresis data have been taken at 4.2 and 50 K over a wide range of magnetic fields on melt textured (MT) and quench melt growth processed (QMGP) YBa(2)Cu(3)Ox samples with 6 vol.% of Y2BaCuOx (211). In order to obtain accurate comparisons of the intragranular critical current densities, the magnetization measurements were performed on finely powdered samples, the average particle size of which was less than the grain size of the original sample. The QMGP samples exhibited substantially larger hysteresis, indicating significantly enhanced flux pinning at these temperatures. At 4.2 K and 5 T, Je increase from 4 x 10(4) A/cm(2) in the MT sample to 5.5 x 10(5) A/cm(2) in the QMGP sample. A possible pinning mechanism related to the observed hysteretic behavior is discussed. C1 [Shi, Donglu; Sengupta, S.; Smith, M.; Wang, Z.] Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. [Biondo, A. C.; Balachandran, U.; Goretta, K. C.] Argonne Natl Lab, Mat & Components Technol Div, Argonne, IL 60439 USA. RP Shi, DL (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. FU U.S. Department of Energy (DOE), Basic Energy Sciences-Materials Sciences; Conservation and Renewable Energy as part of a DOE program to develop electric power technology [W-31-109-Eng-38]; DOE through the Midwest Superconductivity Consortium [DE FG02-90-ER45427] FX This work was supported by the U.S. Department of Energy (DOE), Basic Energy Sciences-Materials Sciences (SS, DS, KCG), and Conservation and Renewable Energy as part of a DOE program to develop electric power technology (ACB, UB), under Contract W-31-109-Eng-38; and by DOE Grant DE FG02-90-ER45427 through the Midwest Superconductivity Consortium (SS). SS is also with the Department of Electrical Engineering, the University of Notre Dame. ACB is also with the Department of Metallurgical and Materials Engineering, the Illinois Institute of Technology. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1034 EP 1036 DI 10.1109/77.233875 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200031 ER PT J AU Moser, EK Tomasch, WJ Furdyna, JK Coffey, MW Clem, JR AF Moser, E. K. Tomasch, W. J. Furdyna, J. K. Coffey, M. W. Clem, J. R. TI TRANSMISSION AND REFLECTION OF SUPERCONDUCTING YBa2Cu3O7-x FILMS AT 35 GHz SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Microwave transmission and reflection measurements are carried out simultaneously on thin films (similar to 2000 angstrom) of YBa2Cu3O7-x having their c axes perpendicular to the LaAlO3 substrate. We determine power transmission and reflection fractions (T, R) as functions of temperature and magnetic field (0C program for supporting this research. Support from Australian Metal Manufacture Ltd. (SXD) and from the Australian Commonwealth Department of Industry, Technology and Commerce (HKL, YCG) is gratefully acknowledged. NR 8 TC 3 Z9 3 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1194 EP 1196 DI 10.1109/77.233338 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200072 ER PT J AU Ginley, DS Martens, JS Venturini, EL Tigges, CP Ashby, C Volk, S AF Ginley, D. S. Martens, J. S. Venturini, E. L. Tigges, C. P. Ashby, C. Volk, S. TI SYNTHESIS AND PROCESSING OF THIN FILMS IN THE Tl-Ca-Ba-Cu-O SYSTEM SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB A number of key processing issues have been identified for the film growth and the subsequent processing of thin films in the Tl-Ca-Ba-Cu-O system. We will discuss the interrelationship between the precursor and the typical ex-situ process schemes. In addition, we will discuss an aqueous photolithographic process technology for sub-micron device fabrication without significant degredation of the surface resistance and the use of rapid thermal processing for contact anneals. C1 [Ginley, D. S.; Martens, J. S.; Venturini, E. L.; Tigges, C. P.; Ashby, C.; Volk, S.] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RP Ginley, DS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. FU U.S. Department of Energy [DE-AC04-76P00789]; Basic Energy Science Branch of DOE FX This work was performed at Sandia National Laboratories and was supported in part by the U.S. Department of Energy under Contract No. DE-AC04-76P00789 and the Basic Energy Science Branch of DOE, The authors would also like to acknowledge the assisstance of Wen Lee of IBM for samples and Tom Plot for processing. D. S. Ginley address 10/1/92 NREL, 1671 Cole Boulevard, Golden, CO 80439, Man. received Aug 24 1992 NR 13 TC 9 Z9 9 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1201 EP 1204 DI 10.1109/77.233336 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200074 ER PT J AU Kim, DH Miller, DJ Hettinger, JD Gray, KE Landis, PG Sharping, JE Eddy, M AF Kim, D. H. Miller, D. J. Hettinger, J. D. Gray, K. E. Landis, P. G. Sharping, J. E. Eddy, M. TI EFFECT OF SUBSTRATE-TWIN-INDUCED MICROSTRUCTURE ON TRANSPORT PROPERTIES OF EPITAXIAL Tl2Ba2CaCu2Ox FILMS IN A MAGNETIC FIELD SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The role of substrate-induced microstructure on transport properties in c-axis oriented epitaxial Tl2Ba2CaCu2Ox films grown on LaAlO3 and SrTiO3 has been studied. For a magnetic field parallel to the Cu-O planes, resistivity and the critical current density, J(c), have been measured as a function of angle theta between the applied field and the direction of transport current. Resistivity dips and enhancement of the critical current density, J(c), were observed for magnetic fields applied parallel to the substrate twins in LaAlO3 in high fields (>= 2 T). Meanwhile for films on SrTiO3, resistivity and J(c) were Lorentz-force independent. C1 [Kim, D. H.; Miller, D. J.; Hettinger, J. D.; Gray, K. E.; Landis, P. G.; Sharping, J. E.] Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. [Eddy, M.] Superconducting Technol Inc, Santa Barbara, CA 93111 USA. RP Kim, DH (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. FU NSF through the ScTC for Superconductivity [DMR 88-09854]; U.S. DOE, Division of Basic Energy Sciences-Materials Sciences [W-31-109-ENG-38] FX This work is partially supported by the NSF(DMR 88-09854) through the ScTC for Superconductivity (DHK), and the U.S. DOE, Division of Basic Energy Sciences-Materials Sciences, under contract #W-31-109-ENG-38 (KEG, JDH). Manuscript recevied August 24, 1992. NR 5 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1208 EP 1210 DI 10.1109/77.233409 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200076 ER PT J AU Hettinger, JD Kim, DH Miller, DJ Hu, JG Gray, KE Sharping, JE Daly, K Pettiette-Hall, C Tkaczyk, JE Deluca, J AF Hettinger, J. D. Kim, D. H. Miller, D. J. Hu, J. G. Gray, K. E. Sharping, J. E. Daly, K. Pettiette-Hall, C. Tkaczyk, J. E. Deluca, J. TI CURRENT TRANSPORT ACROSS GRAIN BOUNDARIES IN TLBa2Ca2Cu3OX THICK POLYCRYSTALLINE FILMS AND YBa2Cu3O7 STEP EDGES SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB We have performed transport measurements in magnetic fields (H//c) up to 10T on a series of YBa2Cu3O7 grain boundaries induced by epitaxial growth on a substrate containing a series of step edges. For this material we find an ;activation energy which goes as U(T)similar to(1-t). Electric field versus current density curves taken at a constant temperature while varying the magnetic field allows a determination of the magnetic field dependence of the activation energy using the Ambagaokar-Halperin model. These values agree with results extracted from the resistive transitions. Similar characterizations of a sample of TlBa2Ca2Cu3Ox are also presented. The temperature dependence of the activation energy for this system may be summarized as U(T)similar to(1-t)(2), suggesting that the grain boundaries behave as SNS juctions. C1 [Hettinger, J. D.; Kim, D. H.; Miller, D. J.; Hu, J. G.; Gray, K. E.; Sharping, J. E.] Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. [Daly, K.; Pettiette-Hall, C.] TRW Space & Technol Grp, Redondo Beach, CA 90278 USA. [Tkaczyk, J. E.; Deluca, J.] Gen Elect Res & Dev, Schenectady, NY 12301 USA. RP Hettinger, JD (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. FU United States Department of Energy, Division of Basic Energy Sciences-Materials Sciences, and Conservation and renewable Energy [W-31-109-ENG-38]; National Science Foundation as part of the Science and Technology Center for Superconductivity [DMR 88-09854] FX This work was supported by the United States Department of Energy, Division of Basic Energy Sciences-Materials Sciences, and Conservation and renewable Energy as a part of a program to develop electric Power Technology, under Contract No. W-31-109-ENG-38 (JDH,DJM,JH,KEG, JS) and by the National Science Foundation as part of the Science and Technology Center for Superconductivity under Contract No. DMR 88-09854 (DHK). NR 12 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1211 EP 1214 DI 10.1109/77.233408 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200077 ER PT J AU Hu, JG Miller, DJ Goretta, KC Poeppel, RB AF Hu, J. G. Miller, D. J. Goretta, K. C. Poeppel, R. B. TI Microstructural Characterization of Ag-Sheathed Tl-Ba-Ca-Cu-O and Bi-Sr-Ca-Cu-O Superconducting Tapes by Analytical Electron Microscopy SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The microstructures of Tl(1223) and Pb-doped Bi(2223) silver tapes produced by the powder-in-tube (PIT) method have been examined by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectrometry (EDS). The Tl tapes annealed below the melting point exhibited fine grains and a high density of pores while tapes subjected to partial melting prior to solid state annealing were fully dense with large grains. However, these tapes also showed an increase in the size and density of impurity particles, particularly CaO and a Ba-Cu rich phase. Silver powders added to the precursors tended to promote the growth of Tl(1223) at lower temperatures but also interfered with the development of texture by providing nucleation sites of random orientations. In contrast, the Bi(2223) tape exhibited a high degree of texture and alignment. The incorporation of silver within the superconducting phase was found to be negligible for both the Tl(1223) and Bi(2223) tapes. C1 [Hu, J. G.; Miller, D. J.; Goretta, K. C.; Poeppel, R. B.] Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RP Hu, JG (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. FU U.S.D.O.E., Divisions of Basic Energy Sciences-Materials Sciences and Superconductivity Pilot Center [W-31-109-ENG-38]; NSF-Office of Science and Technology Centers [STC8809854] FX Research supported by the U.S.D.O.E., Divisions of Basic Energy Sciences-Materials Sciences and Superconductivity Pilot Center under contract #W-31-109-ENG-38, and the NSF-Office of Science and Technology Centers under contract #STC8809854. Manuscript received August 24, 1992. NR 13 TC 3 Z9 3 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1215 EP 1218 DI 10.1109/77.233407 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200078 ER PT J AU Willis, JO Maley, MP Kung, PJ Coulter, JY Peterson, DE Wahlbeck, PG Bingert, JF Phillips, DS AF Willis, J. O. Maley, M. P. Kung, P. J. Coulter, J. Y. Peterson, D. E. Wahlbeck, P. G. Bingert, J. F. Phillips, D. S. TI TRANSPORT AND MAGNETIZATION CRITICAL CURRENT DENSITIES IN TlBa2Ca2Cu3Ox Tapes SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The powder in tube process was used to produce silver-sheathed tapes of TlBa2Ca2Cu3O8+x (Tl-1223). The powder was produced by thalliating a precursor powder mixture to produce the Tl-2223 phase and then heating to drive off excess Tl and reach the Tl-1223 stoichiometry. The tapes were rolled and pressed, each step followed with a 3 h sintering. The 200 mu m thick tapes show little sign of texturing; however, the critical current shows a small (similar to 50%) dependence on the direction of the applied magnetic field. Both transport and magnetization measurents indicate relatively strong pinning at high temperatures. The 75 K self field critical current density is 62 MA/m(2). Transport measurements reveal the presence of weak links at all temperatures, but with a relatively weak field dependence above approximate to 0.1 T. C1 [Willis, J. O.; Maley, M. P.; Kung, P. J.; Coulter, J. Y.; Peterson, D. E.; Wahlbeck, P. G.; Bingert, J. F.; Phillips, D. S.] Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, MS K763, Los Alamos, NM 87545 USA. [Wahlbeck, P. G.] Wichita State Univ, Dept Chem, Wichita, KS 67208 USA. RP Willis, JO (reprint author), Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, MS K763, Los Alamos, NM 87545 USA. FU U S Dept. of Energy, Office of Energy Management FX Work performed under the auspices of the U S Dept. of Energy, Office of Energy Management. NR 9 TC 4 Z9 4 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1219 EP 1221 DI 10.1109/77.233406 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200079 ER PT J AU Kountz, DJ Gai, PL Wilker, C Holstein, WL Pellicone, FM Brainard, RJ AF Kountz, D. J. Gai, P. L. Wilker, C. Holstein, W. L. Pellicone, F. M. Brainard, R. J. TI MICROSTRUCTURAL AND ELECTRONIC PROPERTIES OF HIGHLY ORIENTED Tl0.5Pb0.5Sr2CaCu2O7 FILMS ON LaAlO3 SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Epitaxial Tl0.5Pb0.5Sr2CaCu2O7 films produced by rf magnetron sputtering followed by annealing in the presence of thallium oxide vapor have been produced on (100) LaAlO3 substrates. These films are highly c-axis oriented with rocking curve full width at half maximum less than 0.4. The resulting two copper oxide layer films exhibit microwave surface resistance at 10 GHz of 60 +/- 3 mu Omega at 4.2 K and 498 +/- 10 mu Omega at 70 K (T-c = 88 +/- 2 K). The degree of lattice mismatch between this phase and the LaAlO3 substrate is very small resulting in epitaxial thin films. This material exhibits very little intrinsic defect structure. C1 [Kountz, D. J.; Gai, P. L.; Wilker, C.; Holstein, W. L.; Pellicone, F. M.] Dupont Co, Cent Res & Dev, POB 80304, Wilmington, DE 19880 USA. [Brainard, R. J.] Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Kountz, DJ (reprint author), Dupont Co, Cent Res & Dev, POB 80304, Wilmington, DE 19880 USA. FU U. S. Department of Commerce Advanced Technology Program [70NANB1H122] FX This work was supported by the U. S. Department of Commerce Advanced Technology Program under contract #70NANB1H122. NR 12 TC 9 Z9 9 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1222 EP 1225 DI 10.1109/77.233405 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200080 ER PT J AU Sengupta, S Shi, DL Wang, ZN Smith, M McGinn, PJ AF Sengupta, S. Shi, Donglu Wang, Zuning Smith, M. McGinn, P. J. TI EFFECTIVE ACTIVATION ENERGY IN THE Bi-Sr-Ca-Cu-O SYSTEMS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Magnetic relaxation in the Bi-Sr-Ca-Cu-O systems has been investigated in a wide temperature regime. Previously reported studies of the effective activation energy, U, have been controversial in terms of temperature and field dependence of the critical current density, j(C). We have considered the temperature dependence of j(C) and constructed the U-j (or M) curves for the Bi-Sr-Ca-Cu-O system. We found that at a constant driving force and temperature, U is considerably higher for 2245 samples than for 2223 samples. This enhancement can be attributed to the flux pinning from finely dispersed calcium- and copper- rich precipitates. C1 [Sengupta, S.; Shi, Donglu; Wang, Zuning; Smith, M.] Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. [McGinn, P. J.] Univ Notre Dame, Dept Elect Engn, Notre Dame, IN 46556 USA. RP Sengupta, S (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. FU U.S. Department of Energy, Basic Energy Sciences-Materials Sciences [W-31-109-ENG-38]; Midwest Superconductivity Consortium (DOE) [DE-FG02-90ER45427] FX This work was supported by the U.S. Department of Energy, Basic Energy Sciences-Materials Sciences, under Contract No. W-31-109-ENG-38 (DS, ZW, and MS). SS and PM acknowledge support from the Midwest Superconductivity Consortium (DOE Contract DE-FG02-90ER45427). NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1226 EP 1228 DI 10.1109/77.233404 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200081 ER PT J AU Yoo, SI Kramer, MJ McCallum, RW AF Yoo, S. I. Kramer, M. J. McCallum, R. W. TI SUPERCONDUCTIVITY AND FLUX PINNING IN Nd1+xBa2-xCu3O7+delta SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The substitution of Nd+3 for Ba+2 in Nd1+xBa2-xCu3O7+delta (Nd123ss) increases the occupation of 0(5) sites. For x>0.1 there is a significant depression of T-c and for x<0.1 there is no substantial decrease in T-c within experimental error. T-c vs x is characterized by two plateaus analogous to T-c vs delta in YBa2Cu3O7+delta (Y123). Analysis of oxygen contents of Nd123ss suggests the analogy with Y123 is valid. The transition width and Meissner fraction for all Nd123ss samples are strongly dependent on the sintering temperatures. While T-c is not affected over the range 0 < x < 0.1, the oxygens surrounding the substituted Ba sites are expected to locally suppress the superconducting order parameter. Hysteresis measurements exhibited a small increase in the magnetic J(c), but flux creep measurements showed no apparent effects of this substitution on the flux pinning energy. C1 [Yoo, S. I.; Kramer, M. J.; McCallum, R. W.] Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. RP Yoo, SI (reprint author), Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. FU Office of Basic Science, U.S. Department of Energy [W-7405-ENG-82] FX This work was performed at the Ames Laboratory, Iowa State University and supported by the Director of Energy Research, Office of Basic Science, U.S. Department of Energy under contract No. W-7405-ENG-82. Manuscript received August 24, 1992. NR 13 TC 10 Z9 10 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1232 EP 1235 DI 10.1109/77.233402 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200083 ER PT J AU Li, Q Suenaga, M Hikata, T Sato, K AF Li, Qiang Suenaga, M. Hikata, T. Sato, K. TI LARGE MAGNETIC FIELD INDUCED FLUCTUATION EFFECT IN SUPERCONDUCTING Bi2Sr2Ca2Cu3O10 TAPE SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB We present our study on the magnetic field induced fluctuation effect in a highly textured Bi2Sr2Ca2Cu3O10 tape, based on the magnetization measurement. Extremely large induced excess diamagnetism in high fields was observed at temperatures down to 75 K. In weak fields, fluctuation significantly reduces the diamagnetism of this system just below T-c. The role of this large extended fluctuation effect played in the application of Bi-based superconductor family is discussed. C1 [Li, Qiang; Suenaga, M.] Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. [Hikata, T.; Sato, K.] Sumitomo Elect Ind Ltd, Osaka Res Labs, Osaka 554, Japan. RP Li, Q (reprint author), Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. FU U.S. Department of Energy, Division of Materials Sciences, Office of Basic Sciences [DE-AC02-76CH00016] FX This work was supported by the U.S. Department of Energy, Division of Materials Sciences, Office of Basic Sciences, under Contract No. DE-AC02-76CH00016. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1240 EP 1242 DI 10.1109/77.233400 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200085 ER PT J AU Hampshire, DP Gray, KE Kampwirth, RT AF Hampshire, D. P. Gray, K. E. Kampwirth, R. T. TI SCALING LAWS FOR THE CRITICAL CURRENT DENSITY OF NbN FILMS IN HIGH MAGNETIC FIELDS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB We have measured the critical current density (J(C)) of two NbN films (500 angstrom and 1550 angstrom thick) as a function of temperature in magnetic fields up to 25 Tesla using transport measurements. In both films, the functional form of the volume pinning force F-P obeys the Fietz - Webb scaling law throughout the entire magnetic field and temperature range such that F-P = J(C) x B = alpha.B-C2(m)(T)b(1/2).(1-b)(2) = alpha(1-T/T-C)(m)b(1/2).(1-b)(2) where alpha and alpha* are constants dependent on the film, B-C2(T) is the upper critical field, b = B/B-C2(T) is the reduced magnetic field, T-C is the critical temperature and we find m = 2.7 +/- 0.1. Over a limited range of magnetic fields close to B-C2(T), we can approximate this functional form by: F-P = beta.B-C2(M)(T)b.(1-b)(2) = beta*(1-T/T-C)(M)b.(1-b)(2) where beta and beta* are constants and we find M = 2.6 +/- 0.2. Values of J(c) derived from D.C. magnetisation data obtained using Bean's model show qualitative agreement with the transport measurements throughout the superconducting phase. Despite the marked granularity in the microstructure of these films, we interpret our results as evidence that a flux pinning mechanism determines the transport current density in NbN films in high magnetic fields. C1 [Hampshire, D. P.] Univ Durham, Dept Phys, South Rd, Durham DH1 3LE, England. [Gray, K. E.; Kampwirth, R. T.] Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Hampshire, DP (reprint author), Univ Durham, Dept Phys, South Rd, Durham DH1 3LE, England. OI Hampshire, Damian/0000-0001-8552-8514 FU University Funding Council U.K.; Science and Engineering Council; Department of Energy and Office of Fusion U.S.A. FX These electromagnetic measurements were made by DPH while he was a post-doctoral research scientist at The Applied Superconductivity Center, Madison, Wisconsin. The authors wish to thank Prof. D.C. Larbalestier for his considerable contribution to this work. In addition the authors acknowledge the contribution of Dr. D.W. Capone II for making the samples used in this study and B. Brandt and L. Rubin at The Francis Bitter National Magnet Laboratory. This work has support from the University Funding Council U.K., the Science and Engineering Council and the Department of Energy and Office of Fusion U.S.A. NR 26 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1246 EP 1252 DI 10.1109/77.233398 PN 3 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200087 ER PT J AU ten Kate, HHJ Weijers, HW van Oort, JM AF ten Kate, H. H. J. Weijers, H. W. van Oort, J. M. TI CRITICAL CURRENT DEGRADATION IN Nb3Sn CABLES UNDER TRANSVERSE PRESSURE SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The critical current degradation of a few Rutherford type of Nb3Sn cables are investigated as function of transverse pressure. Moreover a comparison is made between Nb3Sn strands produced according to the Powder-in-Tube, the Bronze and the Modified Jelly Roll process. The (keystoned) Rutherford cables are charged at 11 T with transverse pressures up to 250 MPa. Large differences in critical current reduction are observed, ranging from 6 to about 60% at 200 MPa depending on the type of Nb3Sn. It appears that the irreversible part is about 40% of the total reduction. Moreover, the "irreversible" part shows relaxation and a partial recovery is possible by thermal cycling. C1 [ten Kate, H. H. J.; Weijers, H. W.] Univ Twente, Ctr Appl Superconduct, POB 217, NL-7500 AE Enschede, Netherlands. [van Oort, J. M.] Lawrence Berkeley Lab, Livermore, CA USA. RP ten Kate, HHJ (reprint author), Univ Twente, Ctr Appl Superconduct, POB 217, NL-7500 AE Enschede, Netherlands. FU FOM, the Netherlands Foundation for Fundamental Research on Matter, Utrecht, the Netherlands FX This work was supported in part by FOM, the Netherlands Foundation for Fundamental Research on Matter, Utrecht, the Netherlands. NR 9 TC 12 Z9 12 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1334 EP 1337 DI 10.1109/77.233653 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200110 ER PT J AU Scanlan, RM Dietderich, DR McManaman, P Ghiorso, W AF Scanlan, R. M. Dietderich, D. R. McManaman, P. Ghiorso, W. TI CHARACTERIZATION AND COIL TEST RESULTS FOR A MULTIFILAMENTARY NbTi CONDUCTOR UTILIZING ARTIFICIAL PINNING CENTER TECHNOLOGY SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The introduction of pinning centers via the controlled addition of a second phase, with the correct size and spacing, has been proposed as a method for producing a material with optimum flux pinning and hence a higher critical current density in practical superconductors. The demonstration of such artificial pinning center (APC) materials has been the aim of recent collaborative efforts with several U.S. manufacturers. This paper reports the coil test results for a multifilamentary NbTi conductor fabricated using an APC technique. The conductor showed improved performance compared to earlier APC conductors, and its performance is comparable to that found in conventional multifilamentary NbTi conductors. In addition to coil test results, the paper will report on the low field magnetization, SEM, and TEM studies, and the results will be compared with similar results on conventional NbTi. C1 [Scanlan, R. M.; Dietderich, D. R.; McManaman, P.; Ghiorso, W.] Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RP Scanlan, RM (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU Office of Energy Research, Office of High Energy and Nuclear Physics, Division of High Energy Physics of the U.S. Department of Energy [DE-AC03-76SF00098] FX This work was supported by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, Division of High Energy Physics of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098. NR 7 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1358 EP 1361 DI 10.1109/77.233647 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200116 ER PT J AU Kung, PJ Maley, MP Willis, JO McHenry, ME Murakami, M Tanaka, S AF Kung, P. J. Maley, M. P. Willis, J. O. McHenry, M. E. Murakami, M. Tanaka, S. TI MAGNETIC HYSTERESIS AND FLUX CREEP OF YBa2Cu3Ox GROWN BY THE MELT-POWDER-MELT-GROWTH (MPMG) PROCESS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Magnetic hysteresis and flux creep of melt-powder-melt-growth (MPMG) YBa2Cu3Ox containing nominal 0, 25 and 40 mole% Y2BaCuO5 (211) were measured in the temperature range of 5 to 80 K and in magnetic fields up to 5 T. With the introduced fine dispersion of second phase 211 particles, the critical magnetization current density J(c) shows a weak field dependence over a wide range of temperature, and the effective pinning energy U-eff is much enhanced. From these results, a functional expression U-eff(J, T) = - U-O G(T) (J / J(i)) (n) is obtained, where G(T) = [1 - (T/T-x)(2)](2) with T-x = 82.5 K near the irreversibility temperature. The observed power-law relationship of U-eff(J, T) clearly demonstrates two of three regimes as predicted by the theory of collective flux creep, namely n = 3/2 and 7/9 for J < J(c) and J << J(c), respectively. In addition, the divergence of U-eff at low current densities also suggests the existence of a vortex-glass state. C1 [Kung, P. J.; Maley, M. P.; Willis, J. O.; McHenry, M. E.] Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, POB 1663, Los Alamos, NM 87545 USA. [Kung, P. J.; McHenry, M. E.] Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. [Murakami, M.; Tanaka, S.] Int Superconduct Technol Ctr, Superconduct Res Lab, Koto Ku, Tokyo 135, Japan. RP Kung, PJ (reprint author), Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, POB 1663, Los Alamos, NM 87545 USA. FU United States Department of Energy, Office of Energy Management FX This work was performed under the auspices of the United States Department of Energy, Office of Energy Management. NR 11 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1382 EP 1385 DI 10.1109/77.233641 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200122 ER PT J AU Li, ZX Levy, M Sarma, BK Salem-Sugui, S Shi, DL Crabtree, CW AF Li, Zheng-Xiao Levy, Moises Sarma, Bimal K. Salem-Sugui, S., Jr. Shi, Donglu Crabtree, C. W. TI PENETRATION FIELD STUDIES ON MELT-TEXTURED YBa2Cu3O7-delta FROM LOW FIELD ULTRASONIC MEASUREMENTS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Both attenuation and velocity measurements have been performed in low magnetic fields on a melt-textured sample of YBa2Cu3O7-delta. Transverse waves were propagated along the c-axis at 76 MHz while the temperature was kept constant. Four orientations of the magnetic field H were used. In the a-b plane the field was (1) perpendicular, (2) at 45, or (3) parallel to the polarization direction. The fourth orientation (4) was H parallel to the c-axis. At 77 K, an abrupt change in velocity and attenuation was observed at a field of 10 Gauss for all four orientations. However, the magnitude of the effect decreased as the field orientation was varied from (1) to (4). The position of the abrupt change depends quadratically on the temperature. Because of the lack of anisotropy of the value of the penetration field with magnetic field orientation, we identify it as the penetration field of the matrix surrounding the individual oriented crystallites. There is a maximum in the attenuation change at the penetration field at about 56 K. The effects appear to be produced by the interaction of sound waves with the flux lines which percolate through the Josephson junctions connecting the individual superconducting crystallites. C1 [Li, Zheng-Xiao; Levy, Moises; Sarma, Bimal K.] Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA. [Salem-Sugui, S., Jr.; Shi, Donglu; Crabtree, C. W.] Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Li, ZX (reprint author), Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA. FU K. C. Wang Educational Foundation, Hong Kong; Office of Naval Research; U. S. Department, Basic Energy Sciences Materials Sciences [W-31 - 109 - ENG-38] FX The authors are grateful to Shi-Wan Lin, Qi-Ze Ran and J. Herro for useful discussions and help. Zheng-Xiao Li is grateful to acknowledge the support of K. C. Wang Educational Foundation, Hong Kong. The work at UWM was supported by the Office of Naval Research. The work at ANL was supported by the U. S. Department, Basic Energy Sciences Materials Sciences, under Contract No. W-31 - 109 - ENG-38. NR 11 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1406 EP 1408 DI 10.1109/77.233635 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200128 ER PT J AU Welch, DO AF Welch, D. O. TI CONCERNING FACTORS WHICH DE I ERMINE WHETHER FLUX-LATTICE SHEAR OR PIN BREAKING LIMITS THE CRITICAL CURRENT DENSITY OF SUPERCONDUCTORS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB An elementary model is presented which illustrates the conditions under which flux-lattice shear, rather than pin breaking, limits the critical current density. An expression for the shear strength of the flux-lattice, based on the plasticity of metals and alloys, is used to derive the critical current density, including the effect of thermal activation in the flux creep regime. C1 [Welch, D. O.] Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. RP Welch, DO (reprint author), Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. FU U.S. Department of Energy, Division of Materials Sciences, Office of Basic Energy Sciences [DE-AC02-76CH00016] FX This research was supported by the U.S. Department of Energy, Division of Materials Sciences, Office of Basic Energy Sciences under Contract DE-AC02-76CH00016. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1476 EP 1478 DI 10.1109/77.233616 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200147 ER PT J AU Fleshier, S Kwok, WK Welp, U Downey, J Crabtree, GW AF Fleshier, S. Kwok, W. K. Welp, U. Downey, J. Crabtree, G. W. TI A COMPARISON OF TWIN BOUNDARY PINNING IN NEARLY FULLY STOICHIOMETRIC AND OXYGEN DEFICIENT YBa2Cu3O7-delta SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The angular dependence of the magneto resistance was measured on the same single crystal of YBa2Cu3O7-delta prepared initially with a superconducting transition temperature of 93K and then annealed to obtain a transition temperature of 56.9K. A second oxygen deficient sample was produced with a transition temperature 57.0K and nearly identical transport characteristics. Twin boundary pinning superimposed on flux flow behavior was observed in both the 56.9K and 93.0K states for magnetic field rotation in the ab plane. For magnetic field rotations off the c axis we observe twin boundary pinning only for the nearly stoichiometric state. We find the broadening of the resistive transition in magnetic field (H vertical bar vertical bar c) to occur over a much larger interval of reduced temperature in the deoxygenated state. The enhanced broadening of the resistive transition in magnetic field and absence of twin boundary pinning may indicate that the vortex system is two dimensional, and in general, defects are rendered ineffective in pinning due to the absence of three dimensional collective elastic effects. C1 [Fleshier, S.] Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. Argonne Natl Lab, Ctr Sci & Technol, Argonne, IL 60439 USA. RP Fleshier, S (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. FU U. S. Department of Energy, BES--Materials Science [W-31-109-ENG-38]; NSF-Office of Science and Technology Centers [STC8809854] FX The authors would like to thank K. G. Vandervoort, B. W. Veal, and A. P. Paulikus for useful discussions about various methods of sample preparation. This work was supported by the U. S. Department of Energy, BES--Materials Science under contract #W-31-109-ENG-38 (SF, WKK, JD, GWC) and the NSF-Office of Science and Technology Centers under the contract #STC8809854 (UW) Science and Technology Center for Superconductivity. NR 12 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1483 EP 1486 DI 10.1109/77.233614 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200149 ER PT J AU Vlcek, BM Frischherz, MC Vishwanathan, HK Welp, U Crabtree, GW Kirk, MA AF Vlcek, B. M. Frischherz, M. C. Vishwanathan, H. K. Welp, U. Crabtree, G. W. Kirk, M. A. TI ENHANCEMENTS OF THE CRITICAL CURRENTS OF YBaCuO SINGLE CRYSTALS BY NEUTRON (n) AND PROTON (p) IRRADIATION SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB We present the results of magnetization hysteresis and T-C measurements of neutron and proton irradiated YBaCuO single crystals. The crystals used for comparison were irradiated to a fluence of 2x10(17)n/cm(2) (n, E>0.1MeV) and 1x10(16)p/cm(2) (p, E=3.5MeV). The critical currents at 1T and 10K are enhanced by a factor of 5 for the neutron irradiated and a factor of 9 for the proton irradiated sample respectively. After irradiation the crystals were annealed at 100, 200 and 300 degrees C for 8h each in air. Following each annealing step the critical temperature and the magnetization hysteresis at 10 and 70K was measured. Upon annealing, we observe a decrease of the critical currents, which is more pronounced for the proton irradiated sample. This decrease is related to the removal of point defects or their small clusters. Thus, their contribution to pinning can be studied. The critical temperature decreases after both types of irradiation by about 0.5K and is fully recovered after annealing. C1 [Vlcek, B. M.; Frischherz, M. C.; Vishwanathan, H. K.; Welp, U.; Crabtree, G. W.; Kirk, M. A.] Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RP Vlcek, BM (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. FU U. S. Department of Energy, Basic Energy Sciences-Materials Science [W-31-109-ENG-38]; National Science Foundation-Office of Science and Technology Center for Superconductivity [STC8809854] FX We would like to thank J. Downey for the preparation of the crystals and J. Farmer as well as P. Baldo for irradiating the samples. This work was supported by the U. S. Department of Energy, Basic Energy Sciences-Materials Science under Contract No. W-31-109-ENG-38 (B. M. V., M. C. F., H. K. V., G. W. C., M. A. K.) and the National Science Foundation-Office of Science and Technology Center for Superconductivity, under Contract No. STC8809854 (U. W.) NR 11 TC 3 Z9 3 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1491 EP 1494 DI 10.1109/77.233384 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200151 ER PT J AU Qiang, Q Kramer, MJ Finnemore, DK Snead, CL AF Qiang, Qian Kramer, M. J. Finnemore, D. K. Snead, C. L., Jr. TI Critical Current Enhancement In YBa2Cu3O7-delta Single Crystal By 200 MeV Proton Irradiation SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Radiation damage studies have been carried out using a beam of 200 MeV protons directed along the two major symmetry directions of YBa2Cu3O7-delta. These beams create rather light damage tracks along their path, usually of single ion displacements. Strong pinning then depends on a line of pinning sites parallel to the vortex core. For radiation parallel to the ab-plane, relatively small doses greatly enhance the critical currents parallel to the c-axis and a strong anisotropy is observed depending on the direction of the vortices relative to the damage tracks. In the limit of high dose, 10(16) protons/cm(2), the damage is so uniform that the anisotropy effects are less pronounced. C1 [Qiang, Qian; Kramer, M. J.; Finnemore, D. K.] US DOE, Ames Lab, Ames, IA 50010 USA. [Qiang, Qian; Kramer, M. J.; Finnemore, D. K.] Iowa State Univ, Dept Phys, Ames, IA 50010 USA. [Snead, C. L., Jr.] Brookhaven Natl Lab, Dept Nucl Energy, Upton, NY 11973 USA. RP Qiang, Q (reprint author), US DOE, Ames Lab, Ames, IA 50010 USA. FU U.S. Department of Energy by Iowa State University [W-7405-ENG-82]; Office of Basic Energy Sciences FX Ames Laboratory is operated for the U.S. Department of Energy by Iowa State University under Contract No. W-7405-ENG-82. This work was supported by the Director of Energy Research and the Office of Basic Energy Sciences. Manuscript received August 24, 1992. NR 4 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1495 EP 1497 DI 10.1109/77.233383 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200152 ER PT J AU Telschow, KL O'Brien, TK Lanagan, MT Kaufman, DY AF Telschow, K. L. O'Brien, T. K. Lanagan, M. T. Kaufman, D. Y. TI LOCAL CRITICAL CURRENT MEASUREMENTS ON (Bi,Pb)(2)Sr2Ca2CU3OX TAPE WITH AN ELECTROMAGNETIC PROBE SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The ability to measure critical currents in high T-C superconducting tapes on a local scale is valuable for optimizing the fabrication process. This paper describes the use of induced currents from a small noncontacting electromagnetic probe to determine the critical current density in a (Bi,Pb)(2)Sr2Ca2Cu3Ox/Ag tape on a local scale. The technique forces full field penetration into the tape locally and infers the critical current density from the Bean critical state model, accounting for the Ag overlayers. Critical current images of the tape can be obtained by scanning the probe over the tape surface with spatial resolution on the order of 1.0 mm. Results for tapes with different microstructures are discussed. C1 [Telschow, K. L.; O'Brien, T. K.] Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. [Lanagan, M. T.; Kaufman, D. Y.] Argonne Natl Lab, Argonne, IL 60439 USA. RP Telschow, KL (reprint author), Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. FU U.S. Department of Energy, Office of Energy Research, Office of Basic Energy Sciences, under DOE Idaho Field Office [DE-AC07-76ID01570]; Office of Conservation and Renewable Energy, as part of a DOE program [W-31-109-Eng-38] FX a. This work was supported by the U.S. Department of Energy, Office of Energy Research, Office of Basic Energy Sciences, under DOE Idaho Field Office Contract DE-AC07-76ID01570 and Office of Conservation and Renewable Energy, as part of a DOE program to develop electric power technology, under Contract No. W-31-109-Eng-38. Manuscript received August 24, 1992. NR 7 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1643 EP 1646 DI 10.1109/77.233910 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200190 ER PT J AU Xu, M Polonka, J Goldman, AI Finnemore, DK McKernan, S AF Xu, Ming Polonka, J. Goldman, A. I. Finnemore, D. K. McKernan, Stuart TI GROWTH OF CaO PRECIPITATES IN SUPERCONDUCTING Bi2Sr2Ca1Cu2O8+delta SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Crystallization studies of Bi2Sr2Ca1Cu2O8+delta have been undertaken in order to explore the possibility of growing large oriented grains of this superconductor so that they contain a fine dispersion of tiny CaO precipitates. At low oxygen partial pressure, CaO forms preferentially over the alkaline earth cuprates and it is found to be the dominant precipitate when there is excess Ca. Hot stage environmental electron microscopy and in situ high temperature x-ray studies have been used as the primary diagnostic tools to determine the best conditions for the growth of this fine dispersion. Because CaO is cubic, it forms equiaxed precipitates with diameters in the range of 1 to 3 micrometers. C1 [Xu, Ming; Polonka, J.; Goldman, A. I.; Finnemore, D. K.] USDOE, Ames Lab, Ames, IA 50010 USA. [Xu, Ming; Polonka, J.; Goldman, A. I.; Finnemore, D. K.] Iowa State Univ, Dept Phys & Astron, Ames, IA 50010 USA. [McKernan, Stuart] Univ Minnesota, High Resolut Microscopy Ctr, Minneapolis, MN 55455 USA. RP Xu, M (reprint author), USDOE, Ames Lab, Ames, IA 50010 USA. FU U.S.Department of Energy by Iowa State University [W-7405-ENG-82]; Office of Basic Energy Sciences FX Ames Laboratory is operated for the U.S.Department of Energy by Iowa State University under Contract No. W-7405-ENG-82. This work was supported by the Director of Energy Research and the Office of Basic Energy Sciences. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1647 EP 1651 DI 10.1109/77.233911 PN 3 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200191 ER PT J AU Budhani, RC Zhu, Y Suenaga, M AF Budhani, R. C. Zhu, Y. Suenaga, M. TI THE EFFECTS OF HEAVY-ION IRRADIATION ON SUPERCONDUCTIVITY IN YBa2Cu3O7 EPITAXIAL FILMS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB We report a comparative study of the superconducting behavior in YBa2Cu3O7 epitaxial films irradiated with Ag and Au ions of several hundred MeV energy. The irradiation results in columnar defects of average diameter similar to 55 and similar to 110 angstrom for Ag+21 and Au+24 ions respectively. A universal linear scaling is observed between the fractional areal damage vs the superconducting transition temperature and normal state resistivity. Our results also show that in these films with intrinsically strong pinning, a marginal enhancement in the critical current density (J(C)) occurs when the defect density is <= 5 x 10(10)/cm(2) and the defect diameter is of the order of coherence length. This criterion is satisfied by the silver ions. The damage due to Au+24 ions is much too severe to improve the J(C). C1 [Budhani, R. C.; Zhu, Y.; Suenaga, M.] Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. RP Budhani, RC (reprint author), Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. FU U. S. Department of Energy, Division of Materials Science, Office of Basic Energy Sciences [DE-AC02-76CH00016] FX It is a pleasure to thank D. O. Welch and A. N. Goland for discussions on issues related to radiation damage. We also thank Charles W. Carlson, V. Zajic and the control room staff at Tandem Van de Graaff for their cooperation during the irradiation experiments. This research has been supported by the U. S. Department of Energy, Division of Materials Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76CH00016. NR 10 TC 7 Z9 7 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1675 EP 1678 DI 10.1109/77.233723 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200197 ER PT J AU Andreone, A Kresin, VZ AF Andreone, Antonello Kresin, Vladimir Z. TI ON MICROWAVE PROPERTIES OF HIGH-T-C OXIDES SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The surface resistance of the high-T-c oxides in the low temperature region is studied. The dependence of the losses on the mean free path has been evaluated. The peculiar microwave properties of YBa2Cu3O7-x are explained in the framework of the two-gap model. C1 [Andreone, Antonello; Kresin, Vladimir Z.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Andreone, Antonello] Univ Naples Federico II, Dipartimento Sci Fis, I-80125 Naples, Italy. RP Andreone, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. FU Office of Naval Research [N00014-91-F0006]; National Research Council (C.N.R.) of Italy FX The research of V. Z. K. has been supported by the Office of Naval Research under Contract No. N00014-91-F0006. The research of A. A. has been supported by the National Research Council (C.N.R.) of Italy. NR 13 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1730 EP 1732 DI 10.1109/77.233601 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TH UT WOS:000209703200212 ER PT J AU Overton, WC van Hulsteyn, DB Flynn, ER AF Overton, W. C., Jr. van Hulsteyn, D. B. Flynn, E. R. TI THEORETICAL AND EXPERIMENTAL VERIFICATION OF THE PROPERTIES OF SUPERCONDUCTOR SURFACE IMAGING SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Electric currents in the vicinity of a superconductor induce surface currents which contribute to the complete expression for the magnetic field. The solution can be written in terms of a magnetic scalar potential that satisfies the Neumann condition at the superconducting boundary. A sensing coil whose axis is normal to the surface detects a field component which is the sum of these direct and induced current contributions. As a result of this imaging effect, a single coil acts like a first order gradiometer. Furthermore, it can be shown that the surface deflects noise from distant sources. The primary application of these principles will be the sensing of extremely weak magnetic fields, such as those encountered in magnetoencephalography (MEG), non-destructive evaluation (NDE) and corrosion analysis. C1 [Overton, W. C., Jr.; van Hulsteyn, D. B.; Flynn, E. R.] Univ Calif Los Alamos Natl Lab, Biomagnetism Lab, Grp P6, MS M715, Los Alamos, NM 87545 USA. RP Overton, WC (reprint author), Univ Calif Los Alamos Natl Lab, Biomagnetism Lab, Grp P6, MS M715, Los Alamos, NM 87545 USA. FU U.S. Department of Energy FX This research was supported under the auspices of the U.S. Department of Energy NR 1 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 1930 EP 1933 DI 10.1109/77.233583 PN 4 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TI UT WOS:000209703300034 ER PT J AU Laws, KE Barber, WC Bland, RW Carpenter, JW Johnson, RT Lockhart, J Lee, JS Watson, RM Labov, SE Mears, CA Ellman, B AF Laws, Kenneth E. Barber, William C. Bland, Roger W. Carpenter, Jerry W. Johnson, Robert T. Lockhart, James Lee, Julie S. Watson, Robert M. Labov, Simon E. Mears, Carl A. Ellman, Brett TI A PROTOTYPE DARK MATTER DETECTOR USING A SERIES ARRAY OF ALUMINUM SUPERCONDUCTING TUNNEL JUNCTIONS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB We have fabricated an array of series-connected superconducting aluminum tunnel junctions on the surface of a large sapphire crystal, as a prototype of a detector for massive, weakly interacting elementary particles. Such particles might constitute the missing matter of our galaxy. Tests on a 14-gram crystal with 6-Mev alpha particles gave an energy resolution of 450 keV FWHM (300 keV due to electronics and microphonics alone). We discuss the ultimate energy resolution to be obtained from this type of detector. C1 [Laws, Kenneth E.; Barber, William C.; Bland, Roger W.; Carpenter, Jerry W.; Johnson, Robert T.; Lockhart, James; Lee, Julie S.; Watson, Robert M.] San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94132 USA. [Labov, Simon E.; Mears, Carl A.; Ellman, Brett] Univ Calif Lawrence Livermore Natl Lab, Expt Astrophys Lab, POB 808, Livermore, CA 94550 USA. RP Laws, KE (reprint author), San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94132 USA. FU U.S. Department of Energy [DE-FG03-92ER40711, W-7405-ENG-48]; NSF Center for Particle Astrophysics at the University of California at Berkeley FX We would like to acknowledge funding from the U.S. Department of Energy under Grant Number DE-FG03-92ER40711 at SFSU and contract no. W-7405-ENG-48 at LLNL, and from the NSF Center for Particle Astrophysics at the University of California at Berkeley. NR 7 TC 0 Z9 0 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 2076 EP 2079 DI 10.1109/77.233448 PN 4 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TI UT WOS:000209703300067 ER PT J AU Mears, CA Labov, SE Morris, GW Cunningham, CE Le Gros, MA Silver, EH Barfknecht, AT Madden, NW Landis, DA Goulding, FS Bland, RW Laws, KE Dynes, RC AF Mears, C. A. Labov, Simon E. Morris, G. W. Cunningham, C. E. Le Gros, M. A. Silver, Eric H. Barfknecht, A. T. Madden, Norman. W. Landis, Don A. Goulding, Fred S. Bland, Roger W. Laws, Kenneth E. Dynes, R. C. TI ENERGY RESOLVING X-RAY DETECTORS USING NIOBIUM ABSORBERS AND MULTIPLE QUASIPARTICLE TUNNELING BETWEEN TWO ALUMINUM TRAPS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB We are developing superconducting tunnel junction devices for use as high-resolution, high-efficiency x-ray spectrometers. We have tested a device with niobium x-ray absorbing layers coupled to two aluminum layers on either side of the tunneling barrier which serve as quasiparticle traps. These devices were fabricated photolithographically using a modified niobium/aluminum/niobium trilayer fabrication process. Our first devices have a very thin barrier with specific normal state resistance of 1.5 x 10(-6) Omega cm(2), and also exhibit very low leakage current (< 15 nA below 200 mK). The energy resolution at 6 keV was 120 eV FWHM. We estimate that each quasiparticle tunnels an average of 8 times before recombining, increasing the total charge transferred and decreasing the effects of electronic noise. C1 [Mears, C. A.; Labov, Simon E.; Morris, G. W.; Cunningham, C. E.; Le Gros, M. A.; Silver, Eric H.] Univ Calif Lawrence Livermore Natl Lab, Expt Astrophys Lab, POB 808,L-401, Livermore, CA 94550 USA. [Barfknecht, A. T.] Conductus Inc, 969 West Maude Ave, Sunnyvale, CA 94086 USA. [Madden, Norman. W.; Landis, Don A.; Goulding, Fred S.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Elect Engn, MS 29-100, Berkeley, CA 94720 USA. [Bland, Roger W.; Laws, Kenneth E.] San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94132 USA. [Dynes, R. C.] Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Mears, CA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Expt Astrophys Lab, POB 808,L-401, Livermore, CA 94550 USA. FU IGPP-LLNL; California Space Institute; U.S. Department of Energy small business innovation research grant [DE-FG-3-91ER81109]; U.S. Department of Energy by Lawrence Livermore National Laboratory [W-7405-ENG-48] FX We wish to thank John Rowell for his support of this project, and Dan Prober for useful discussions. Early work on this project was supported by grants from IGPP-LLNL and the California Space Institute. The foundry at Conductus was established in collaboration with Hewlett-Packard Laboratories. Fabrication of the junctions was supported by a U.S. Department of Energy small business innovation research grant, contract number DE-FG-3-91ER81109. Design, testing and analysis was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract No. W-7405-ENG-48. NR 10 TC 6 Z9 6 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 2092 EP 2095 DI 10.1109/77.233444 PN 4 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TI UT WOS:000209703300071 ER PT J AU Verghese, S Richards, PL Fork, DK Char, K Geballe, TH AF Verghese, S. Richards, P. L. Fork, D. K. Char, K. Geballe, T. H. TI DESIGN OF HIGH-T-c SUPERCONDUCTING BOLOMETERS FOR A FAR INFRARED IMAGING ARRAY SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB The design of high-T-c superconducting bolometers for use in a far infrared imaging array from wavelengths 30 - 100 mu m is discussed. Measurements of the voltage noise in thin films of YBa2Cu3O7-delta on yttria-stabilized zirconia buffer layers on silicon substrates are used to make performance estimates. Useful opportunities exist for imaging and spectroscopy with bolometer arrays made on micro-machined silicon membranes. A circuit on each pixel which performs some signal integration can improve the sensitivity of large two-dimensional arrays of bolometers which use multiplexed readout amplifiers. C1 [Verghese, S.; Richards, P. L.] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. [Verghese, S.; Richards, P. L.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. [Fork, D. K.] Xerox Palo Alto Res Ctr, Palo Alto, CA 94304 USA. [Char, K.] Conductus Inc, Sunnyvale, CA 94086 USA. [Geballe, T. H.] Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. RP Verghese, S (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. FU Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U.S. Department of Energy [DE-AC03-76SF00098]; Conductus Inc.; Air Force Office of Scientific Research (AFOSR) [F49620-89-C-0017]; Xerox Palo Alto Research Center FX This work was supported in part by the Director, Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098 (for sv, PLR), by Conductus Inc. (for KC), by the Air Force Office of Scientific Research (AFOSR) under Contract No. F49620-89-C-0017 (for DKF, THG), and by Xerox Palo Alto Research Center (for DKF). NR 16 TC 6 Z9 6 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 2115 EP 2119 DI 10.1109/77.233919 PN 4 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TI UT WOS:000209703300077 ER PT J AU Nahum, M Richards, PL Mears, CA AF Nahum, M. Richards, P. L. Mears, C. A. TI DESIGN ANALYSIS OF A NOVEL HOT-ELECTRON MICROBOLOMETER SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB We propose a novel antenna coupled microbolometer which makes use of the weak coupling between electrons and phonons in a metal at low temperatures. The radiation is collected by a planar lithographed antenna and thermalized in a thin metal strip. The resulting temperature rise of the electrons is detected by a tunnel junction, where part of the metal strip forms the normal electrode. All components are deposited directly on a substrate so that arrays can be conveniently produced by conventional lithographic techniques. The active area of the bolometer is thermally decoupled by its small volume, by the thermal resistance between the electrons and phonons in the strip, and by the reflection of quasiparticles at the interface between the strip and the superconducting antenna. Design calculations based on a metal volume of 2x6x0.05 mu m(3) at an operating temperature of T= 100 mK give an NEP approximate to 3x10(-19) WHZ(-1/2) time constant approximate to 10 mu s, and responsivity approximate to 10(9) V/W. The calculated sensitivity is almost two orders of magnitude higher than that of the best available direct detectors of millimeter and submillimeter radiation operated at the same temperature. C1 [Nahum, M.; Richards, P. L.] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. [Nahum, M.; Richards, P. L.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. [Mears, C. A.] Univ Calif Lawrence Livermore Natl Lab, Expt Astrophys Lab, L-401,POB 808, Livermore, CA 94550 USA. RP Nahum, M (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. FU Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U. S. Department of Energy [DE-AC03-76SF00098] FX The authors gratefully acknowledge many fruitful discussions with D. E. Prober. This work was supported by the Director, Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U. S. Department of Energy under Contract No. DE-AC03-76SF00098. NR 14 TC 40 Z9 40 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 2124 EP 2127 DI 10.1109/77.233921 PN 4 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TI UT WOS:000209703300079 ER PT J AU Martens, JS Hietala, VM Plut, TA Ginley, DS Vawter, GA Tigges, CP Siegal, MP Phillips, JM Hou, SY AF Martens, J. S. Hietala, V. M. Plut, T. A. Ginley, D. S. Vawter, G. A. Tigges, C. P. Siegal, M. P. Phillips, Julia M. Hou, S. Y. TI FLUX FLOW MICROELECTRONICS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB Flux-flow based devices such as the superconducting flux flow transistor and magnetically controlled long junctions have been made from thin films of TlCaBaCuO and YBaCuO. The devices are based on the magnetic control of flux flow in their respective structures: a long junction or an array of weak links. The equivalent circuits of the two devices are similar: a low impedance input control line, an output impedance of 3-20 Omega and an active current-controlled element. The long junctions have tended to be slower, have lower gain and be somewhat less noisy than their counterparts. The performance of circuits such as narrowband and distributed amplifiers (50 GHz bandwidths, noise figures < 3 dB), phase shifters (continuous with < 2 dB loss 4-40 GHz), logic gates (2-3 ps gate delays) and memories made using these devices will be compared and analyzed. C1 [Martens, J. S.; Hietala, V. M.; Plut, T. A.; Ginley, D. S.; Vawter, G. A.; Tigges, C. P.; Siegal, M. P.] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. [Phillips, Julia M.; Hou, S. Y.] AT&T Bell Labs, Murray Hill, NJ 07974 USA. RP Martens, JS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. FU U. S. Department of Energy [DE-AC04-76P00789]; Office of Naval Research FX This work was performed at Sandia National Labs and was in part supported by the U. S. Department of Energy under contract No. DE-AC04-76P00789 and in part by the Office of Naval Research. The authors would like to thank G. Hohenwarter, I. E. Nordman and J. B. Beyer of the University of Wisconsin and R. Withers of Conductus for useful discussions. NR 18 TC 37 Z9 37 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 2295 EP 2302 DI 10.1109/77.233545 PN 4 PG 8 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TI UT WOS:000209703300122 ER PT J AU Miklich, AH Koelle, D Dantsker, E Nemeth, DT Kingston, JJ Kromann, RF Clarke, J AF Miklich, A. H. Koelle, D. Dantsker, E. Nemeth, D. T. Kingston, J. J. Kromann, R. F. Clarke, J. TI BICRYSTAL YBCO DC SQUIDS WITH LOW NOISE SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB We have fabricated 12 dc SQUIDs by laser depositing YBa2Cu3O7-x on a SrTiO3 bicrystal substrate with a misorientation angle of 24 degrees. At 77K all twelve devices had acceptable values of critical current, resistance and voltage modulation produced by an external magnetic field. The white noise energy of one device with an estimated inductance of 41 pH was 1.8 x 10(-30) JHz(-1). The noise power scaled as 1/f at frequencies below about 1kHz, however; by using a bias current reversal scheme we were able to reduce this noise by two orders of magnitude at 1 Hz, to a value of about 1.5 x 10(-29) JHz(-1). We made a magnetometer by coupling the SQUID to a flux transformer with a 5-turn input coil. The measured magnetic field gain was 60, and the white noise 36ff Hz(-1/2). However, the transformer produced relatively large levels of 1/f flux noise, not reduced by the bias reversal scheme, that limited the noise at 1 Hz to 1.7 pT Hz(-1/2). A single-layer magnetometer with a single-turn pick up loop is briefly described. C1 [Miklich, A. H.; Koelle, D.; Dantsker, E.; Nemeth, D. T.; Kingston, J. J.; Kromann, R. F.; Clarke, J.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Dept Phys, Ctr Adv Mat,Mat Sci Div, Berkeley, CA 94720 USA. RP Miklich, AH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Dept Phys, Ctr Adv Mat,Mat Sci Div, Berkeley, CA 94720 USA. RI Koelle, Dieter/E-5111-2011 FU California Competitive Technology Program; Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U.S. Department of Energy [DE-AC03-76SF00098]; Deutsche Forschungs Gemeinschaft FX This work was supported by the California Competitive Technology Program and by the Director, Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U.S. Department of Energy under contract number DE-AC03-76SF00098. A. H. Miklich was supported by the Fannie and John Hertz Foundation. D. Koelle acknowledges support by the Deutsche Forschungs Gemeinschaft. NR 13 TC 37 Z9 38 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 2434 EP 2437 DI 10.1109/77.233947 PN 4 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TI UT WOS:000209703300155 ER PT J AU Martens, JS Hietala, VM Ginley, DS Tigges, CP Plut, TA Truman, JK Track, EK Young, KH Young, RT AF Martens, J. S. Hietala, V. M. Ginley, D. S. Tigges, C. P. Plut, T. A. Truman, J. K. Track, E. K. Young, K. H. Young, R. T. TI HTS-BASED SWITCHED FILTER BANKS AND DELAY LINES SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB For a number of communications and other applications, switched filter banks (some channelizers) and switched delay lines (phase shifters) are extremely useful. Since YBaCuO and TLCaBaCuO filters and delay lines have shown significant performance enhancements over their conventional counterparts, a purely superconducting version of the switched assemblies could result in additional improvements. A thermal switch has been developed that provides good isolation and insertion loss with adequate switching times to allow a monolithic approach to the switched lines and filter banks. Filter banks in the 8-11 GHz range have been demonstrated with insertion losses < 1 dB and out -of -band rejection greater than a package -limited 50 dB. Switched delay lines have been fabricated with insertion losses less than 0.3 dB/bit and peak phase deviations from linearity of less than 5 degrees over 30 GHz bandwidths. C1 [Martens, J. S.; Hietala, V. M.; Ginley, D. S.; Tigges, C. P.; Plut, T. A.] Sandia Natl Labs, Org 1154, POB 5800, Albuquerque, NM 87185 USA. [Truman, J. K.] CVC Prod, 525 Lee Rd, Rochester, NY 14603 USA. [Track, E. K.] Hypres Inc, 175 Clearbrook Rd, Elmsford, NY 10523 USA. [Young, K. H.; Young, R. T.] Energy Convers Devices, 1675 W Maple Rd, Troy, MI 48084 USA. RP Martens, JS (reprint author), Sandia Natl Labs, Org 1154, POB 5800, Albuquerque, NM 87185 USA. FU U. S. Department of Energy [DE-AC04-76P00789]; Office of Naval Research FX This work was performed at Sandia National Labs and was supported in part by the U. S. Department of Energy under contract No. DE-AC04-76P00789 and in part by the Office of Naval Research. NR 8 TC 9 Z9 9 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 1993 VL 3 IS 1 BP 2824 EP 2827 DI 10.1109/77.233494 PN 4 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V43TI UT WOS:000209703300248 ER PT J AU LUBLINSKY, B FRADKOV, A AF LUBLINSKY, B FRADKOV, A TI A COMPARISON OF ADAPTIVE AND NONADAPTIVE FEEDBACK FOR DISCRETE-TIME PLANTS WITH DEAD-TIME SO IEEE TRANSACTIONS ON AUTOMATIC CONTROL LA English DT Note AB The control of plants with unknown dead time and parameters is considered. The goal of control is to stabilize plant output at a given level. The performance of the optimal, nonadaptive algorithm in the case of uncertain knowledge of parameters is evaluated and compared with that of the adaptive algorithm proposed in the article. The effective regions for both algorithms are evaluated. Simulation results confirming the efficiency of the adaptive algorithm and the performance estimates are presented. C1 LENINGRAD MECH INST,ST PETERSBURG,RUSSIA. RP LUBLINSKY, B (reprint author), FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. RI Fradkov, Alexander/J-3814-2013 OI Fradkov, Alexander/0000-0002-5633-0944 NR 5 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9286 J9 IEEE T AUTOMAT CONTR JI IEEE Trans. Autom. Control PD MAR PY 1993 VL 38 IS 3 BP 492 EP 495 DI 10.1109/9.210154 PG 4 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA KX916 UT WOS:A1993KX91600017 ER PT J AU MARTENS, JS ZIPPERIAN, TE HIETALA, VM GINLEY, DS TIGGES, CP PHILLIPS, JM SIEGAL, MP AF MARTENS, JS ZIPPERIAN, TE HIETALA, VM GINLEY, DS TIGGES, CP PHILLIPS, JM SIEGAL, MP TI SUPERCONDUCTING FLUX FLOW DIGITAL CIRCUITS SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article ID FILMS AB We have developed a family of digital logic circuits based on superconducting flux flow transistors that show high speed, reasonable signal levels, large fan-out, and large noise margins. The circuits are made from high-temperature superconductors (HTS) and have been shown to operate at over 90 K. NOR gates have been demonstrated with fan-outs of more than 5 and fully loaded switching times less than a fixture-limited 50 ps. Ring-oscillator data suggest inverter delay times of about 40 ps when using a 3-mum linewidths. Simple flip-flops have also been demonstrated showing large noise margins, response times of less than 30 ps, and static power dissipation on the order of 30 nW. Among other uses, this logic family is appropriate as an interface between logic families such as single flux quantum and conventional semiconductor logic. C1 SANDIA NATL LABS,DEPT ADV MAT & DEVICES,ALBUQUERQUE,NM 87185. SANDIA NATL LABS,COMPOUND SEMICONDUCTOR DEVICE RES GRP,ALBUQUERQUE,NM 87185. AT&T BELL LABS,THIN FILMS RES GRP,MURRAY HILL,NJ 07974. NR 7 TC 11 Z9 11 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD MAR PY 1993 VL 40 IS 3 BP 656 EP 660 DI 10.1109/16.199373 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA KM203 UT WOS:A1993KM20300026 ER PT J AU MOLYNEAUX, JE WITTEN, A AF MOLYNEAUX, JE WITTEN, A TI DIFFRACTION TOMOGRAPHIC IMAGING IN A MONOSTATIC MEASUREMENT GEOMETRY SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Note AB Diffraction tomography (DT) is an imaging technique in which spatial variations in refractive index are reconstructed from measured data. The basis for DT is the Generalized Slice Theorem (GST) relating a known function of the measured data to the spatially variable refractive index, subject to a weak scattering approximation. Forms of the GST have been developed for a number of measurement configurations based on bistatic geometries employing arrays of sources and receivers. Here the problem of imaging with scalar waves for a monostatic measurement geometry is considered. GST's are derived for two dimensions employing several simplifying assumptions. The quality of the images and limitations of these simplifying assumptions are investigated for several two-dimensional algorithms using simulated data. It is found that one particular monostatic inversion formula yields good image quality and is not substantially limited by the necessary simplifying assumption. The motivation for this study is the quest for enhanced signal processing algorithms for remote sensing with ground penetrating radar. The imaging algorithms, however, have applications in medical ultrasound and nondestructive evaluation. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP MOLYNEAUX, JE (reprint author), WIDENER UNIV,DEPT MECH ENGN,CHESTER,PA 19013, USA. NR 11 TC 40 Z9 41 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 MAR PY 1993 VL 31 IS 2 BP 507 EP 511 DI 10.1109/36.214927 PG 5 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA LD280 UT WOS:A1993LD28000019 ER PT J AU TING, A HUA, TQ WALKER, JS PICOLOGLOU, BF AF TING, A HUA, TQ WALKER, JS PICOLOGLOU, BF TI LIQUID-METAL FLOW IN A RECTANGULAR DUCT WITH THIN METAL WALLS AND WITH A NONUNIFORM MAGNETIC-FIELD SO INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE LA English DT Article ID AREA AB This paper treats the steady flow of an electrically conducting, incompressible liquid in a duct with a constant rectangular cross section, with thin, electrically conducting walls and with a non-uniform transverse magnetic field which is parallel to two duct walls. With the x axis along the centerline of the duct, the dimensionless magnetic field B = B(x)(x, y)x + B(y)(x, y)y, where x and y are Cartesian unit vectors, while B(x) and B(y) are odd and even functions of y, respectively. For a small magnetic Reynolds number, B(x) and B(y) satisfy the Cauchy-Riemann equations and boundary conditions at the pole faces of the external magnet. Previous treatments have used a simplified magnetic field B = B(y)(x)y, even though this field does not satisfy the Cauchy-Riemann equations. We consider a magnetic field in which B(y) at the plane of symmetry varies from 0.98 to 0.54 over a short axial distance. For this field the maximum values of B(x) and of the y variation of B(y) are 0.25 and 0.125 in the liquid-metal region. These values are certainly significant, but they are neglected in the simplified magnetic field model. Nevertheless the results for the simplified and complete magnetic fields are virtually identical, so that the simplified field gives excellent results. Previous treatments have also assumed that the Hartmann number M is large. A possible error arises from the implicit assumption that alpha = cM 1/2 much greater than 1, where c is the wall conductance ratio, while realistic values of alpha are generally not particularly large. Comparison of the three-dimensional results for alpha much greater than 1 and for alpha = O(1) reveals that the results for alpha much greater than 1 can be corrected with simple scaling factors derived from much simpler solutions for fully developed flow. C1 UNIV ILLINOIS,URBANA,IL 61801. ARGONNE NATL LAB,ARGONNE,IL 60439. NR 7 TC 14 Z9 14 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0020-7225 J9 INT J ENG SCI JI Int. J. Eng. Sci. PD MAR PY 1993 VL 31 IS 3 BP 357 EP 372 DI 10.1016/0020-7225(93)90011-I PG 16 WC Engineering, Multidisciplinary SC Engineering GA KN754 UT WOS:A1993KN75400002 ER PT J AU VANVORIS, P MILLARD, WD THOMAS, J URBAN, D AF VANVORIS, P MILLARD, WD THOMAS, J URBAN, D TI TERRA-VISION - THE INTEGRATION OF SCIENTIFIC ANALYSIS INTO THE DECISION-MAKING PROCESS SO INTERNATIONAL JOURNAL OF GEOGRAPHICAL INFORMATION SYSTEMS LA English DT Article ID FOREST AB Providing an effective tool for risk assessment of terrestrial environmental resources requires a decision support system which will combine scientific analysis and the decision-making process. The goal of such a system is to provide a scientifically-based method for establishing and evaluating the potential effects of a policy or decision. To meet this goal a computing platform must be established which can run interactively a diverse set of models representing environmental, atmospheric, economic and political issues, and provide an integrated visualized output for decision makers. The decision support tool must be able to manipulate and display disparate information at the appropriate scale, over time and space. Hierarchical modelling, integrated information management systems, geographical information systems, and visualization systems are enabling technologies which provide one possible framework for implementing an effective decision support system. An application-oriented approach was used to examine the requirements and relationships needed to integrate analytical models tightly into a general decision support system. Forest modelling and its relationships to global climate change were the specific application used to prototype such an integrated system. This article introduces the scope and goals established using this application-oriented approach to developing a decision support system for risk assessment of terrestrial environmental resources, TERRA-Vision. It identifies critical design issues, such as the scaling, inter-operability and presentation of information. The article presents a conceptual framework, a design methodology and software used to develop the TERRA-Vision proof-of-concept demonstration system. Lessons learned are provided as part of the conclusions and areas identify where prototype development validated the conceptual framework and provided valuable insight on key issues relating to the development of more generalized decision support platforms. Finally, the conceptual framework is extended to provide an effective method for the development of an integrated scientific analysis and decision-making process. C1 UNIV VIRGINIA, DEPT ENVIRONM SCI, CHARLOTTESVILLE, VA 22903 USA. RP VANVORIS, P (reprint author), PACIFIC NW LAB, 900 BATTELLE BLVD, RICHLAND, WA 99352 USA. NR 11 TC 9 Z9 9 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0269-3798 J9 INT J GEOGR INF SYST JI Int. J. Geogr. Inf. Syst. PD MAR-APR PY 1993 VL 7 IS 2 BP 143 EP 164 DI 10.1080/02693799308901947 PG 22 WC Geography; Information Science & Library Science SC Geography; Information Science & Library Science GA LH919 UT WOS:A1993LH91900005 ER PT J AU EDDY, CA LOONEY, B AF EDDY, CA LOONEY, B TI 3-DIMENSIONAL DIGITAL IMAGING OF ENVIRONMENTAL DATA - SELECTION OF GRIDDING PARAMETERS SO INTERNATIONAL JOURNAL OF GEOGRAPHICAL INFORMATION SYSTEMS LA English DT Article AB Three-dimensional imaging is a powerful technique for the visualization and interpretation of environmental data. The success of the process is linked to careful, technically-justifiable selection of variable parameters during the gridding and imaging process. The impacts of various approaches to gridding and possible setting of parameters on the final image and volume calculations were examined by generating alternative images for a very well characterized contaminated site in layered coastal plain sediments. To image properly scattered data collected at close intervals in wells from layered geological media, a higher grid density in the z direction is required along with a weighting factor to emphasize the influence of data in the x and y directions. For steeply-varying contaminant concentration data, the best results were obtained by gridding the log of the property value; an anti-log transformation is carried out to restore property values to the correct value before the visualization file is prepared. The techniques and recommendations made in this article were designed for modelling contaminant values with very steep gradients dispersed in a strongly anisotropic media. These recommendations may not apply directly to other sites but the process of selecting parameters should be similar. RP EDDY, CA (reprint author), WESTINGHOUSE SAVANNAH RIVER CO,SAVANNAH RIVER LAB,BLDG 773-42A,AIKEN,SC 29802, USA. NR 4 TC 7 Z9 7 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0269-3798 J9 INT J GEOGR INF SYST JI Int. J. Geogr. Inf. Syst. PD MAR-APR PY 1993 VL 7 IS 2 BP 165 EP 172 DI 10.1080/02693799308901948 PG 8 WC Geography; Information Science & Library Science SC Geography; Information Science & Library Science GA LH919 UT WOS:A1993LH91900006 ER PT J AU PARK, HM AHLUWALIA, RK IM, KH AF PARK, HM AHLUWALIA, RK IM, KH TI 3-DIMENSIONAL RADIATION IN ABSORBING EMITTING SCATTERING MEDIA USING THE MODIFIED DIFFERENTIAL APPROXIMATION SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article AB The modified differential approximation (MDA) first proposed by Olfe and recently extended by Modest is applied to a three-dimensional absorbing-emitting-scattering medium bounded by non-black walls. Numerical techniques are developed to solve for the radiation fields due to wall emission and medium emission. The techniques are evaluated in terms of the computer memory requirement, CPU time and numerical accuracy. For a model problem, the modified differential approximation is compared against the zone method, the P1 approximation, the P3 approximation, S4 and S6. MDA is shown to be superior to the P1 and P3 approximations and to compare favorably with S(N) solutions for all conditions of optical depth. RP PARK, HM (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 7 TC 12 Z9 12 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0017-9310 J9 INT J HEAT MASS TRAN JI Int. J. Heat Mass Transf. PD MAR PY 1993 VL 36 IS 5 BP 1181 EP 1189 DI 10.1016/S0017-9310(05)80088-2 PG 9 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA KV199 UT WOS:A1993KV19900005 ER PT J AU DUFFEY, TA AF DUFFEY, TA TI OPTIMAL BOLT PRELOAD FOR DYNAMIC LOADING SO INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL SYMP ON STRUCTURAL CRASHWORTHINESS AND FAILURE CY APR 14-16, 1993 CL UNIV LIVERPOOL, LIVERPOOL, ENGLAND HO UNIV LIVERPOOL AB A simple spring-mass model is developed for closure bolting systems, including the effects of bolt prestress. An analytical solution is developed for the case of an initially peaked, exponentially decaying internal pressure pulse acting on the closure. The dependence of peak bolt stresses and deflections on bolt prestress level is investigated and an optimal prestress that minimizes peak bolt stress is found in certain cases. The effects of closure bending response and the resulting bending stresses induced in bolts are not considered in the simple model. Vulnerability curves are developed for bolted closure systems to provide rapid evaluation of the dynamic capacity of designs for a range of bolt prestress. RP DUFFEY, TA (reprint author), LOS ALAMOS NATL LAB,GRP M-4,MS P940,LOS ALAMOS,NM 87545, USA. NR 9 TC 7 Z9 9 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0020-7403 J9 INT J MECH SCI JI Int. J. Mech. Sci. PD MAR-APR PY 1993 VL 35 IS 3-4 BP 257 EP 265 DI 10.1016/0020-7403(93)90080-E PG 9 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA KX641 UT WOS:A1993KX64100007 ER PT J AU MANESCHY, CE MASSOUDI, M GHONEIMY, A AF MANESCHY, CE MASSOUDI, M GHONEIMY, A TI HEAT-TRANSFER ANALYSIS OF A NON-NEWTONIAN FLUID PAST A POROUS PLATE SO INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS LA English DT Article AB The flow of an incompressible third-grade fluid past an infinite porous plate subject to suction and blowing at the plate is studied numerically. Two distinct heat transfer problems are studied. In the first case, the plate is assumed to be at a higher temperature than the fluid; and in the second case, the plate is assumed to be insulated. The non-dimensional form of the equations are presented, and the velocity and the temperature profiles for various values of the appropriate dimensionless parameters are also given. C1 US DOE, PITTSBURGH ENERGY TECHNOL CTR, POB 10940, PITTSBURGH, PA 15236 USA. UNIV PITTSBURGH, DEPT MECH ENGN, PITTSBURGH, PA 15261 USA. HALWAN UNIV, DEPT MECH POWER ENGN, CAIRO, EGYPT. PONTIFICIA UNIV CATOLICA RJ, DEPT MECH ENGN, BR-22453 RIO DE JANEIRO, BRAZIL. NR 10 TC 7 Z9 7 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0020-7462 J9 INT J NONLINEAR MECH JI Int. J. Non-Linear Mech. PD MAR PY 1993 VL 28 IS 2 BP 131 EP 143 DI 10.1016/0020-7462(93)90052-M PG 13 WC Mechanics SC Mechanics GA KR476 UT WOS:A1993KR47600001 ER PT J AU ITO, T BAKER, SC STICKLEY, CD PEAK, JG PEAK, MJ AF ITO, T BAKER, SC STICKLEY, CD PEAK, JG PEAK, MJ TI DEPENDENCE OF THE YIELD OF STRAND BREAKS INDUCED BY GAMMA-DNA ON THE PHYSICAL CONDITIONS OF EXPOSURE - WATER-CONTENT AND TEMPERATURE SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID SINGLE-STRAND; AQUEOUS-SOLUTION; HYDRATED DNA; PLASMID DNA; RADIATION; IRRADIATION; COLLAGEN; CELLS AB The induction by Co-60 gamma-rays of DNA breaks, revealed by relaxation (single-strand breaks, SSBs) and linearization (double-strand breaks, DSBs) of supercoiled plasmid DNA, was measured under three ir-radiation conditions, the DNA being in a dry, humid, or aqueous state in the absence of oxygen, at 25 or -196-degrees-C (77 K). Yields of strand breaks (3.0 x 10(-10) SSB/Gy.Da and 2.6 x 10(-11) DSB/Gy-Da) in DNA exposed to a stream of humidified nitrogen were higher than those in the dry condition (5.7 x 10(-11) SSB/Gy.Da and 3.2 x 10(-12) DSB/Gy.Da), but both these yields were markedly lower than those measured for DNA in aqueous solution at a concentration of 73 mug/cm3 (1.14 x 10(-7) SSB/Gy.Da and 5.4 x 10(-9) DSB/Gy-Da). Over 100-fold fewer SSBs were observed in the frozen aqueous system compared with the nonfrozen liquid state, whereas in the dry and humid states, freezing did not affect the yield as much. The same trend was observed for DSBs. However, the induction of SSBs was more affected than that of DSBs by freezing in the aqueous systems. An interesting reverse relationship was observed in humid systems. The observed linearity of DSB induction with radiation dose supported a single-event mechanism. A comparison of G values for humid systems revealed that the role of bound water in radiation damage becomes significant in the nonfrozen state. Based on these and other measurements of strand breaks under different conditions, the significance of bound and free water on the yields of DNA strand breaks by gamma-rays is discussed, and the relevance of these results to the in vivo situation outlined. C1 ARGONNE NATL LAB,DIV BIOL & MED RES,ARGONNE,IL 60439. NR 32 TC 70 Z9 70 U1 1 U2 8 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 MAR PY 1993 VL 63 IS 3 BP 289 EP 296 DI 10.1080/09553009314550391 PG 8 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 KR477 UT WOS:A1993KR47700002 PM 8095278 ER PT J AU DRAKE, JB GEIST, GA HICKS, HR KLIEWER, KL STOCKS, GM TORAN, LE WORLEY, PH AF DRAKE, JB GEIST, GA HICKS, HR KLIEWER, KL STOCKS, GM TORAN, LE WORLEY, PH TI CENTERS OF SUPERCOMPUTING - THE CENTER FOR COMPUTATIONAL SCIENCES AT OAK-RIDGE-NATIONAL-LABORATORY SO INTERNATIONAL JOURNAL OF SUPERCOMPUTER APPLICATIONS AND HIGH PERFORMANCE COMPUTING LA English DT Article ID PERFORMANCE; DENSITIES; STATES; ALLOYS RP DRAKE, JB (reprint author), OAK RIDGE NATL LAB,POB 2008,OAK RIDGE,TN 37831, USA. RI Stocks, George Malcollm/Q-1251-2016 OI Stocks, George Malcollm/0000-0002-9013-260X NR 32 TC 0 Z9 0 U1 1 U2 2 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 SN 1078-3482 J9 INT J SUPERCOMPUT AP JI Int. J. Supercomput. Appl. High Perform. Comput. PD SPR PY 1993 VL 7 IS 1 BP 3 EP 14 DI 10.1177/109434209300700101 PG 12 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications SC Computer Science GA LK557 UT WOS:A1993LK55700001 ER PT J AU KELLOGG, GL AF KELLOGG, GL TI ATOMIC-LEVEL STUDIES OF DIFFUSION ON METAL-SURFACES SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS LA English DT Article DE FIELD ION MICROSCOPE; SURFACE DIFFUSION; CLUSTER NUCLEATION; ADATOM ID SCANNING-TUNNELING-MICROSCOPY; FIELD-ION MICROSCOPE; PLATINUM ADATOM CLUSTERS; 110 TUNGSTEN SURFACES; SELF-DIFFUSION; EXCHANGE MECHANISM; SUBMONOLAYER FILMS; SINGLE ADATOMS; PT(001); IRIDIUM AB The unique attributes of the field ion microscope have enabled researchers to obtain detailed information on the diffusion of individual atoms and the nucleation of small clusters on metal surfaces. In this article I describe the experimental methods used in field ion microscope studies of these processes and discuss recent results relating to the discovery of novel diffusion modes and unexpected cluster configurations on fcc metal surfaces. RP SANDIA NATL LABS, ALBUQUERQUE, NM 87185 USA. NR 39 TC 8 Z9 8 U1 0 U2 1 PU JAPAN SOC APPLIED PHYSICS PI TOKYO PA KUDAN-KITA BUILDING 5TH FLOOR, 1-12-3 KUDAN-KITA, CHIYODA-KU, TOKYO, 102-0073, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Brief Commun. Rev. Pap. PD MAR PY 1993 VL 32 IS 3B BP 1463 EP 1469 DI 10.1143/JJAP.32.1463 PG 7 WC Physics, Applied SC Physics GA KW401 UT WOS:A1993KW40100021 ER PT J AU BROMMER, KD LARSON, BE NEEDELS, M JOANNOPOULOS, JD AF BROMMER, KD LARSON, BE NEEDELS, M JOANNOPOULOS, JD TI MODELING LARGE SURFACE RECONSTRUCTIONS ON THE CONNECTION MACHINE SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT 1ST INTERNATIONAL WORKSHOP ON NANOSCALE SCIENCE : PRESENT AND ITS FUTURE CY SEP 23-26, 1992 CL SENDAI INT CTR, SENDAI, JAPAN HO SENDAI INT CTR DE SI(111) SURFACE RECONSTRUCTION; PARALLEL COMPUTATION; DENSITY FUNCTIONAL THEORY; SCANNING TRANSMISSION MICROSCOPY; ADATOMS; DANGLING BONDS; SURFACE MODELING ID ENERGY ELECTRON-DIFFRACTION; DENSITY-FUNCTIONAL THEORY; STACKING-FAULT MODEL; REAL-SPACE; TUNNELING MICROSCOPE; MOLECULAR-DYNAMICS; SI(111)7X7; SI(111)-(7X7); PSEUDOPOTENTIALS; SILICON AB Using a massively parallel computer, we undertake an ab initio investigation of the Si(111)-(7 x 7) surface reconstruction. Calculation of the total energy of an approximately 700 effective atom supercell at an 8 Ry plane wave cutoff allows us to determine (1) the energy difference between the (7 x 7) and (2 x 1) reconstructions, (2) the relaxed atomic geometry, (3) the scanning tunneling microscope topographs as a function of bias voltage and (4) the occupied and unoccupied electronic states. C1 LOCKHEED SANDERS,HUDSON,NH 03051. THINKING MACHINES,CAMBRIDGE,MA 02142. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551. RP BROMMER, KD (reprint author), MIT,DEPT PHYS,CAMBRIDGE,MA 02139, USA. NR 34 TC 23 Z9 23 U1 0 U2 0 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PD MAR PY 1993 VL 32 IS 3B BP 1360 EP 1367 DI 10.1143/JJAP.32.1360 PG 8 WC Physics, Applied SC Physics GA KW401 UT WOS:A1993KW40100005 ER PT J AU BROWN, GN STYRIS, DL AF BROWN, GN STYRIS, DL TI ELUCIDATION OF MECHANISMS THAT CONTROL THE ELECTROTHERMAL ATOMIZATION OF TIN CHLORIDE SO JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY LA English DT Article DE TIN CHLORIDE; MASS SPECTROMETRY; ELECTROTHERMAL ATOMIC ABSORPTION SPECTROMETRY ID ATOMIC-ABSORPTION SPECTROMETRY AB Mechanisms that control the electrothermal atomization of SnCl2 were investigated by monitoring real-time mass spectra of gaseous species generated in pyrolytic graphite coated graphite furnaces during the atomization cycle. Vacuum and atmospheric pressure vaporization were used to help differentiate between homogeneous gas-phase and condensed-phase interactions. During vacuum vaporization from tube atomizers, free Sn was not observed and the only molecular species detected were SnO(g) and SnCl2(g). During atmospheric pressure vaporization, the observed molecular species consisted primarily of SnCl2(g) and SnO(g). Free Sn, as determined by mass spectrometry, was absent from the centre of the atomizer. Free Sn was present, however, as determined by atomic absorption spectrometry. This suggests that atomization occurs at the regions of lowest temperature in the atomizer, i.e., the end regions. The thermal decomposition of homogeneous gas-phase species cannot account for the formation of free Sn because of the paucity of Sn(g) in the centre of the atomizer. However, SnO(g) interactions with the cooler surface regions of the graphite atomizer do explain these data. Desorption of the resulting Sn(ad) can then account for the free Sn that was observed as the atomizer temperature increased. This argument is supported by mass spectrometric results acquired when vaporizing at atmospheric pressure from capillary-like graphite cups that were heated to exhibit temperature gradients along their lengths. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 21 TC 7 Z9 7 U1 0 U2 0 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 0267-9477 J9 J ANAL ATOM SPECTROM JI J. Anal. At. Spectrom. PD MAR PY 1993 VL 8 IS 2 BP 211 EP 216 DI 10.1039/ja9930800211 PG 6 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA LB836 UT WOS:A1993LB83600003 ER PT J AU MYERS, SM BROWN, GA REVESZ, AG HUGHES, HL AF MYERS, SM BROWN, GA REVESZ, AG HUGHES, HL TI DEUTERIUM INTERACTIONS WITH ION-IMPLANTED SIO2 LAYERS IN SILICON SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MOLECULAR-HYDROGEN; VITREOUS SILICA; MOS DEVICES; INTERFACE; BREAKDOWN; DIFFUSION; CENTERS; OXIDES; BEAM AB The interactions of deuterium gas (D2) with implantation-formed Si-SiO2-Si structures were investigated in the temperature range 500-1000-degrees-C using nuclear-reaction analysis. At 600-degrees-C and above there is substantial permeation of D through the overlying Si layer, and this D becomes stably bound within the buried SiO2. The reactions within the implantation-formed oxide differ significantly from those in thermal oxides and are characterized by two distinct time regimes. In the first regime there is a rapid transient reaction which, at least at 600-degrees-C, is controlled by permeation through the Si overlayer. After the initial transient there is a much slower reaction within the oxide, prominent at 700-degrees-C and higher, which is controlled by a reaction barrier. The results indicate that the implantation-formed oxides contain more numerous hydrogen-reactive sites than do silica or thermal oxides on Si, and further that the number of these sites is substantially increased by Si epitaxial deposition. Deuterium permeation through the Si overlayer was used to determine the permeability of hydrogen in Si at 600-degrees-C for the first time. C1 TEXAS INSTRUMENTS INC,DALLAS,TX 75265. REVESZ ASSOCIATES,BETHESDA,MD 20817. USN,RES LAB,WASHINGTON,DC 20375. RP MYERS, SM (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 32 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 1993 VL 73 IS 5 BP 2196 EP 2206 DI 10.1063/1.353122 PG 11 WC Physics, Applied SC Physics GA KT868 UT WOS:A1993KT86800021 ER PT J AU SIEGELE, R ROTH, J SCHERZER, BMU PENNYCOOK, SJ AF SIEGELE, R ROTH, J SCHERZER, BMU PENNYCOOK, SJ TI DAMAGE AND DEUTERIUM TRAPPING IN HIGHLY-ORIENTED PYROLYTIC-GRAPHITE SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID THERMAL-DESORPTION; RADIATION-DAMAGE; RE-EMISSION; CARBON; BOMBARDMENT; IMPLANTATION; PROFILES AB In this work the buildup of damage due to deuterium implantation in highly-oriented pyrolytic graphite (HOPG) is investigated. HOPG was implanted with 10-30 keV D3+ at different target temperatures between room temperature and 773 K with fluences from 10(14) to 10(18) D/cm2. Subsequently, the damage due to the implantation and the retained deuterium were measured by Rutherford backscattering (RBS) in a channeling direction (RBSc) and by the D(He-3, p)alpha nuclear reaction analysis (NRA), respectively. The damage of selected samples was additionally observed with transmission electron microscopy (TEM). The initial trapping efficiency is unity in the whole temperature and energy range. The maximum retention of the deuterium, however, depends on the temperature and implantation energy. The damage in HOPG measured with RBSc starts to saturate at 5 X 10(15) D/cm2 (295 K) and 1.3 X 10(17) D/cm2 (773 K). Both fluences are well below the fluence at which amorphization is observed in TEM. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP SIEGELE, R (reprint author), MAX PLANCK INST PLASMA PHYS,EURATOM ASSOC,BOLTZMANNSTR 2,W-8046 GARCHING,GERMANY. NR 43 TC 29 Z9 29 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 MAR 1 PY 1993 VL 73 IS 5 BP 2225 EP 2233 DI 10.1063/1.353126 PG 9 WC Physics, Applied SC Physics GA KT868 UT WOS:A1993KT86800025 ER PT J AU WHITE, DP AF WHITE, DP TI THE EFFECT OF IONIZING AND DISPLACIVE RADIATION ON THE THERMAL-CONDUCTIVITY OF ALUMINA SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MICROWAVE-HEATING DEVICES; CERAMIC WINDOWS; MECHANICAL RELIABILITY; ALPHA-AL2O3; SAPPHIRE AB The effects of ionizing and displacive radiation on the thermal conductivity of alumina at high temperatures have been studied. The phonon scattering relaxation times for several scattering mechanisms have been used to determine the effect on the thermal conductivity. The scattering mechanisms considered are scattering by electrons excited into the conduction band, vacancies, aluminum precipitates, and voids. It is found that under irradiation conditions where the electrical conductivity and dielectric loss tangent are greatly increased there is not a significant decrease in the thermal conductivity due to phonon-electron scattering. The conditions under which the scattering due to vacancies, aluminum precipitates, and voids each produces a significant reduction in the thermal conductivity are discussed. RP WHITE, DP (reprint author), OAK RIDGE NATL LAB, DIV MET & CERAM, OAK RIDGE, TN 37831 USA. NR 30 TC 17 Z9 17 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 1993 VL 73 IS 5 BP 2254 EP 2258 DI 10.1063/1.353130 PG 5 WC Physics, Applied SC Physics GA KT868 UT WOS:A1993KT86800029 ER PT J AU CHEN, HY HEALD, SM AF CHEN, HY HEALD, SM TI COMPARISON OF GLANCING ANGLE EXTENDED X-RAY ABSORPTION FINE-STRUCTURE OBTAINED FROM FLUORESCENCE AND REFLECTIVITY MEASUREMENTS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ANOMALOUS-SCATTERING FACTORS; EXAFS; REGIONS AB At glancing angles the extended x-ray absorption fine structure (EXAFS) can be determined from either the fluorescence or reflectivity signals. This article presents a critical comparison of the two detection channels as they apply to thin film interface problems. Both signals are distorted by anomalous dispersion effects, and our previous method for correcting the distortions in the fluorescence signal is shown to work equally well for the reflectivity signal. Using results from a pure gold film and a Cu-Al bilayer as examples, it is demonstrated that both signals can be corrected to obtain accurate EXAFS information. Fluorescence detection generally offers greater sensitivity, improved signal-to-noise and less distortion of the EXAFS, but the reflectivity signal may be easier to obtain for in situ measurements. A complication for fluorescence is the possibility of an additional contribution to the signal caused by x rays scattered into the substrate layer. While generally small, this contribution is difficult to remove from the measured signal, and may make the reflectivity the preferred signal for some experiments. C1 BROOKHAVEN NATL LAB,DIV MAT SCI,UPTON,NY 11973. 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 MAR 1 PY 1993 VL 73 IS 5 BP 2467 EP 2471 DI 10.1063/1.353105 PG 5 WC Physics, Applied SC Physics GA KT868 UT WOS:A1993KT86800062 ER PT J AU KILLEEN, KP AF KILLEEN, KP TI ULTRAVIOLET-ABSORPTION AND PHOTODISSOCIATION OF AS4 SO JOURNAL OF APPLIED PHYSICS LA English DT Note ID MOLECULAR-BEAM EPITAXY; GAAS; GROWTH; EFFICIENCY AB Ultraviolet absorption spectroscopy has been used to measure the photodissociative absorption band of As4 in the spectral range from 190 to 370 nm. The As4 absorption bands are assigned to 1A1 --> 1T1A,B Rydberg transitions with measured cross sections of 7.8+/-0.5X10(-18) cm2 at 256.7 nm and 1.4+/-0.1X10(-17) cm2 at 193.7 nm. Photolysis of As4 is shown to yield a large As2/As4 ratio at modest photon intensities, thus suggesting a viable nonthermal method for generation of arsenic dimers for epitaxy of III-V materials. RP KILLEEN, KP (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 16 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 1993 VL 73 IS 5 BP 2596 EP 2598 DI 10.1063/1.353076 PG 3 WC Physics, Applied SC Physics GA KT868 UT WOS:A1993KT86800089 ER PT J AU SAULT, AG AF SAULT, AG TI AN AUGER-ELECTRON SPECTROSCOPY STUDY OF THE ACTIVATION OF IRON FISCHER-TROPSCH CATALYSTS .1. HYDROGEN ACTIVATION SO JOURNAL OF CATALYSIS LA English DT Article ID CARBON-MONOXIDE; PROMOTED FE; LEED-AES; OXIDATION; SURFACES; POTASSIUM; REDUCTION; PHOTOEMISSION; ADSORPTION; MECHANISM RP SAULT, AG (reprint author), SANDIA NATL LABS,DEPT FUEL SCI 6211,ALBUQUERQUE,NM 87185, USA. NR 48 TC 18 Z9 18 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 0021-9517 J9 J CATAL JI J. Catal. PD MAR PY 1993 VL 140 IS 1 BP 121 EP 135 DI 10.1006/jcat.1993.1072 PG 15 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA KN969 UT WOS:A1993KN96900009 ER PT J AU SAULT, AG DATYE, AK AF SAULT, AG DATYE, AK TI AN AUGER-ELECTRON SPECTROSCOPY STUDY OF THE ACTIVATION OF IRON FISCHER-TROPSCH CATALYSTS SO JOURNAL OF CATALYSIS LA English DT Article ID CARBON-MONOXIDE; POLYCRYSTALLINE IRON; FILAMENTOUS CARBON; PROMOTED FE; REDUCTION; POTASSIUM; SURFACE; HYDROGENATION; KINETICS; OXIDATION C1 UNIV NEW MEXICO,DEPT CHEM & NUCL ENGN,ALBUQUERQUE,NM 87131. RP SAULT, AG (reprint author), SANDIA NATL LABS,DEPT FUEL SCI 6211,ALBUQUERQUE,NM 87185, USA. NR 45 TC 17 Z9 17 U1 0 U2 3 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 MAR PY 1993 VL 140 IS 1 BP 136 EP 149 DI 10.1006/jcat.1993.1073 PG 14 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA KN969 UT WOS:A1993KN96900010 ER PT J AU HUNT, RD ANDREWS, L AF HUNT, RD ANDREWS, L TI REACTIONS OF PULSED-LASER EVAPORATED URANIUM ATOMS WITH MOLECULAR-OXYGEN - INFRARED-SPECTRA OF UO, UO2, UO3, UO2+, UO22+, AND UO3-O2 IN SOLID ARGON SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MATRIX-ISOLATION; RAMAN AB Uranium atoms from the Nd:YAG laser ablation of a uranium target were codeposited with molecular oxygen and excess argon at 12 K. Infrared spectra following the U+O2 reaction revealed a wide range of reaction products. The 776.0 cm-1 band due to UO2 was the strongest product absorption, strong UO3 bands were observed at 852.5 and 745.5 cm-1, and a weak UO absorption appeared at 819.8 cm-1. These product absorptions are in agreement with earlier work, which evaporated UO2 from a tungsten Knudsen cell at 2000-degrees-C. The O-16(2)/O-18(2) reaction gave only (UO2)-O-16 and (UO2)-O-18, which verified an insertion mechanism. New product absorptions were observed at 952.3, 892.3, and 842.4 cm-1. The 842.4 cm-1 absorption due to the UO3-O2 complex and the 892.3 cm-1 band assigned to the charge-transfer complex (UO2+)(O2-) grew markedly at the expense of the other uranium oxides during annealing the matrix to allow diffusion and reaction of O2. With 25% O-16(2), 50% (OO)-O-16-O-18 and 25% O-18(2) samples, the 952.3 cm-1 band became a sharp triplet at 952.3, 936.5, and 904.5 cm-1 and exhibited an isotopic ratio appropriate for a linear OUO species. Agreement of this band with uranyl ion spectra suggests assignment to a (UO22+) complex. Mechanisms of formation of charged species are discussed. C1 UNIV VIRGINIA,DEPT CHEM,CHARLOTTESVILLE,VA 22901. RP HUNT, RD (reprint author), OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831, USA. NR 37 TC 94 Z9 95 U1 2 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 MAR 1 PY 1993 VL 98 IS 5 BP 3690 EP 3696 DI 10.1063/1.464045 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR111 UT WOS:A1993KR11100012 ER PT J AU MACDONALD, RG LIU, KP AF MACDONALD, RG LIU, KP TI THE DYNAMIC RENNER-TELLER EFFECT .3. ROVIBRONIC ENERGY-TRANSFER PATHWAYS IN THE NCO((X)OVER-TILDE 2-PI) + HE SYSTEM SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ROTATIONALLY INELASTIC-COLLISIONS; POLYATOMIC-MOLECULES; ELECTRONIC STATES; SCATTERING; PI AB As a linear triatomic radical in an electronic state with LAMBDA not-equal O bends, the vibrationally excited levels are split as a result of vibronic interactions. This is the well-known Renner-Teller effect. Reported here is the first study of the collision-induced transitions between these Renner-Teller components. It is found that the pathways for these processes are highly selective and their efficiencies, in some cases, can compete with rotationally inelastic collisions. A simple, intuitive argument is presented to underscore the physical mechanisms for this finding. Preliminary, more rigorous theoretical analysis confirms the essential ideas of the proposed interpretations. RP MACDONALD, RG (reprint author), ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439, USA. RI Liu, Kopin/F-7929-2012 NR 21 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 1993 VL 98 IS 5 BP 3716 EP 3725 DI 10.1063/1.464049 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR111 UT WOS:A1993KR11100016 ER PT J AU LIM, KP MICHAEL, JV AF LIM, KP MICHAEL, JV TI THE THERMAL-DECOMPOSITION OF CH3CL USING THE CL-ATOM ABSORPTION METHOD AND THE BIMOLECULAR RATE-CONSTANT FOR O+CH3 (1609-2002-K) WITH A PYROLYSIS PHOTOLYSIS-SHOCK TUBE TECHNIQUE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID COLLISION RATE CONSTANTS; FALL-OFF RANGE; UNIMOLECULAR REACTIONS; TRANSITION-STATES; ABSOLUTE RATE; KINETICS; TEMPERATURE; COMBUSTION; LOOSENESS; DIFFUSION AB Rate constants for the thermal decomposition of CH3Cl and the atom-radical reaction O+CH3 have been measured in shock tube experiments. The decomposition of CH3Cl, at three loading pressures, has been carried out between 1663-2059 K with mixtures that varied from 1.25 to 24.9 ppm in Ar. The first-order rate constant k1 = 1.21 X 10(10) Xexp( -27 838 K/T) s-1 describes the experimental results to within +/- 29% at the one standard deviation level. The bimolecular rate experiment has then been carried out over the temperature range 1609-2002 K using mixtures of SO2 (49.9 ppm) and CH3Cl (5.14 and 8.2 ppm) in Ar. The technique first involves allowing the thermal decomposition to proceed forming CH3 radicals, and this is then followed by delayed photolysis of SO2 forming the 0-atom species. This new method is called the pyrolysis photolysis-shock tube (PyPh-ST) technique. A reaction mechanism had to be used to simulate the measured 0-atom profiles for the various experimental conditions, and the bimolecular rate constant was found to be temperature independent with a value of k2 = 1.4 X 10(-10) CM3 molecule-1 s-1. Reactions (1) and (2) are both theoretically discussed. RP LIM, KP (reprint author), ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439, USA. RI Michael, Joe/E-3907-2010 NR 53 TC 47 Z9 47 U1 0 U2 4 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 MAR 1 PY 1993 VL 98 IS 5 BP 3919 EP 3928 DI 10.1063/1.464019 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR111 UT WOS:A1993KR11100037 ER PT J AU PALMER, BJ GARRETT BC AF PALMER, BJ GARRETT BC TI CONSTANT PRESSURE CONSTANT TEMPERATURE SIMULATIONS OF LIQUID WATER AND CARBON-DIOXIDE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; DOPPLER INFRARED-SPECTRUM; CO2 DIMER; MODELS; 25-DEGREES-C; FORMULATION; SYSTEMS; LIGHT AB Rigid and flexible models of liquid water and carbon dioxide are simulated using Andersen-Nose constant pressure-constant temperature molecular dynamics. Both equilibrium and dynamical properties are investigated and compared with constant energy simulations of the same models. The results of the constant pressure-constant temperature simulations are in very close agreement with the constant energy simulations, even for d dynamical quantities. C1 PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. RP PACIFIC NW LAB, DEPT ANALYT SCI, RICHLAND, WA 99352 USA. RI Garrett, Bruce/F-8516-2011 NR 39 TC 24 Z9 24 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 1993 VL 98 IS 5 BP 4047 EP 4058 DI 10.1063/1.465041 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR111 UT WOS:A1993KR11100053 ER PT J AU HALLEY, JW RUSTAD, JR RAHMAN, A AF HALLEY, JW RUSTAD, JR RAHMAN, A TI A POLARIZABLE, DISSOCIATING MOLECULAR-DYNAMICS MODEL FOR LIQUID WATER SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SIMULATION; SYSTEMS AB We describe a molecular dynamics model for dissociable, polarizable water. The model, which describes both the static and dynamic properties of real water quite reasonably, contains the following features: Self-consistent local fields are calculated in an extension of an earlier algorithm in which the dipole moments of the water are treated as dynamical variables. An intramolecular three-body potential assures that the molecular properties of water are in agreement with experiment. Ewald methods are used to take account of monopole-dipole and dipole-dipole as well as monopole-monopole interactions. The model was optimized using a Monte Carlo procedure in the parameter space which is described. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. RP HALLEY, JW (reprint author), UNIV MINNESOTA, SCH PHYS & ASTRON, MINNEAPOLIS, MN 55455 USA. NR 25 TC 132 Z9 133 U1 1 U2 11 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 MAR 1 PY 1993 VL 98 IS 5 BP 4110 EP 4119 DI 10.1063/1.465046 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR111 UT WOS:A1993KR11100058 ER PT J AU MESSINA, M SCHENTER, GK GARRETT, BC AF MESSINA, M SCHENTER, GK GARRETT, BC TI APPROXIMATE PATH INTEGRAL METHODS FOR PARTITION-FUNCTIONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID VIBRATIONAL-ENERGY-LEVELS; BOLTZMANN DENSITY MATRIX; TRANSITION-STATE THEORY; NONLINEAR-SYSTEMS; QUANTUM; POTENTIALS; CONSTANTS AB We review several approximate methods for evaluating quantum mechanical partition functions with the goal of obtaining a method that is easy to implement for multidimensional systems but accurately incorporates quantum mechanical corrections to classical partition functions. A particularly promising method is one based upon an approximation to the path integral expression of the partition function. In this method, the partition-function expression has the ease of evaluation of a classical partition function, and quantum mechanical effects are included by a weight function. Anharmonicity is included exactly in the classical Boltzmann average and local quadratic expansions around the centroid of the quantum paths yield a simple analytic form for the quantum weight function. We discuss the relationship between this expression and previous approximate methods and present numerical comparisons for model one-dimensional potentials and for accurate three-dimensional vibrational force fields for H2O and SO2. RP MESSINA, M (reprint author), PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. RI Garrett, Bruce/F-8516-2011; Schenter, Gregory/I-7655-2014 OI Schenter, Gregory/0000-0001-5444-5484 NR 39 TC 24 Z9 24 U1 0 U2 2 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 MAR 1 PY 1993 VL 98 IS 5 BP 4120 EP 4127 DI 10.1063/1.465021 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR111 UT WOS:A1993KR11100059 ER PT J AU LOONG, CK SODERHOLM, L ABRAHAM, MM BOATNER, LA EDELSTEIN, NM AF LOONG, CK SODERHOLM, L ABRAHAM, MM BOATNER, LA EDELSTEIN, NM TI CRYSTAL-FIELD EXCITATIONS AND MAGNETIC-PROPERTIES OF TMPO4 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RAMAN-SCATTERING; SPECTRA; INTENSITIES; OPERATOR; TM-3+; YB-3+; YPO4 AB The magnetic-excitation spectrum of TmPO4 has been studied using inelastic neutron scattering techniques. Sharp crystal-field transitions were observed in spectra obtained at 15 and 100 K, yielding new information regarding the energy-level structure of the Tm3+ ground-multiplet splitting. The data were analyzed using a Hamiltonian that included the atomic free-ion and crystal-field interactions for an f12 Configuration. Using the Tm free-ion parameters derived from optical spectroscopy of Tm3+ diluted in a LuPO4 host, a set of crystal-field parameters were obtained for Tm3+ in pure TmPO4. The calculated magnetic spectra of TmPO4 agree very well with the results of neutron and Raman measurements. The calculated bulk magnetic susceptibility of TmPO4 exhibits a large anisotropy at low temperature and is in good agreement with the experimental data. A significant contribution to the specific heat from the Tm3+ crystal-field states was found at temperatures below 100 K. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720. RP LOONG, CK (reprint author), ARGONNE NATL LAB,DIV INTENSE PULSED NEUTRON SOURCE & CHEM,ARGONNE,IL 60439, USA. RI Boatner, Lynn/I-6428-2013 OI Boatner, Lynn/0000-0002-0235-7594 NR 41 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 1993 VL 98 IS 5 BP 4214 EP 4222 DI 10.1063/1.465028 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR111 UT WOS:A1993KR11100068 ER PT J AU ADRIANI, PM CHAKRABORTY, AK AF ADRIANI, PM CHAKRABORTY, AK TI DYNAMICS OF RELAXATION AT STRONGLY INTERACTING POLYMER-SOLID INTERFACES - EFFECTS OF CHAIN ARCHITECTURE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID KINETIC ISING-MODEL; GLASS-TRANSITION; ADSORPTION; ADHESION; ALUMINUM AB The relaxation dynamics of a polymer chain strongly adsorbed to a solid surface are simulated via a kinetic Ising model that includes chain connectivity constraints (steric hindrance, rotational strain, and configurational entropy). The two polymer architectures examined consist of one or two chemisorbing functional groups per segment. In both architectures, the chemisorbed polymer chain is trapped in nonequilibrium conformational states at low temperatures, but relaxes to equilibrium at higher temperatures with stretched exponential (KWW) relaxation kinetics. The average relaxation time for the two pendant group architecture has a strongly non-Arrhenius temperature dependence that obeys the Vogel-Fulcher law. In contrast, average relaxation times for the one pendant group architecture cannot be described b the Vogel-Fulcher law. C1 LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. NR 47 TC 20 Z9 20 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 MAR 1 PY 1993 VL 98 IS 5 BP 4263 EP 4274 DI 10.1063/1.465033 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR111 UT WOS:A1993KR11100073 ER PT J AU GEERS, A KAPPERT, J TEMPS, F SEARS, TJ AF GEERS, A KAPPERT, J TEMPS, F SEARS, TJ TI STIMULATED-EMISSION PUMPING SPECTROSCOPY OF CH3O (X)OVER-TILDE2E, NU-6) - NEW OBSERVATIONS ON THE JAHN-TELLER EFFECT SO JOURNAL OF CHEMICAL PHYSICS LA English DT Note ID METHOXY; SPECTRUM; STATE; MOLECULE; NCO AB Experiments have been carried out using hot ban laser induced fluorescence (LIF) excitation and stimulated emission pumping (SEP) spectroscopy to characterize the excited doubly degenerate nu6 vibrational mode of CH3O (X2E) which is of interest with respect to the Jahn-Teller effect in the molecule. Rotationally resolved spectra were recorded for the A2 A1 <-> X2E, 6(1)0 and 3(1)0(6)1(0) bands. The observed line structures indicate that these bands must be assigned to DELTAj=3/2 parallel (DELTAK=0) vibronic bands. No evidence could yet be obtained for the corresponding DELTAj=1/2 vibronic transitions assumed previously. The results imply that the linear Jahn-Teller effect for nu6 is very small. Instead, coupling between the A2A1 and the X2E states by a pseudo-Jahn-Teller interaction operator is suggested as a plausible mechanism for the observation of the forbidden transitions. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RP GEERS, A (reprint author), MAX PLANCK INST STROMUNGSFORSCH,BUNSENSTR 10,W-3400 GOTTINGEN,GERMANY. RI Sears, Trevor/B-5990-2013 OI Sears, Trevor/0000-0002-5559-0154 NR 22 TC 39 Z9 39 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 MAR 1 PY 1993 VL 98 IS 5 BP 4297 EP 4300 DI 10.1063/1.465036 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA KR111 UT WOS:A1993KR11100076 ER PT J AU MORSS, LR DAY, PP FELINTO, C BRITO, H AF MORSS, LR DAY, PP FELINTO, C BRITO, H TI STANDARD MOLAR ENTHALPIES OF FORMATION OF Y2O3, HO2O3, AND ER2O3 AT THE TEMPERATURE 298.15-K SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article ID LANTHANIDE ELEMENTS; THERMOCHEMISTRY; THERMODYNAMICS RP MORSS, LR (reprint author), ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439, USA. RI Felinto, Maria/H-2347-2014 NR 33 TC 19 Z9 20 U1 1 U2 3 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 MAR PY 1993 VL 25 IS 3 BP 415 EP 422 DI 10.1006/jcht.1993.1045 PG 8 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA KP701 UT WOS:A1993KP70100015 ER PT J AU HAMEED, S SPERBER, KR MEINSTER, A AF HAMEED, S SPERBER, KR MEINSTER, A TI TELECONNECTIONS OF THE SOUTHERN OSCILLATION IN THE TROPICAL ATLANTIC SECTOR IN THE OSU COUPLED UPPER OCEAN ATMOSPHERE GCM SO JOURNAL OF CLIMATE LA English DT Article ID SEA-SURFACE TEMPERATURE; GENERAL-CIRCULATION MODEL; NORTHEAST BRAZIL; RAINFALL ANOMALIES; EL-NINO; PREDICTION; CLIMATE; VARIABILITY; SIMULATION; DROUGHTS AB The Oregon State University coupled upper ocean-atmosphere GCM has been shown to qualitatively simulate the Southern Oscillation. A composite analysis of the warm and cold events simulated in this 23-year integration has been performed. During the low phase of the Southern Oscillation, when warm anomalies occur in the eastern Pacific, the model simulates for the Atlantic region during March-May 1) a deficit of precipitation over the tropical South American continent, 2) Caribbean and Gulf of Mexico sea level pressure and sea surface temperature are in phase with the eastern Pacific anomalies, while those east of the Nordeste region are out of phase, and 3) northeast trade winds are anomalously weak and southwest trade winds are anomalously strong (as infer-red from surface current anomalies). The anomalies in the oceanic processes are induced by perturbations in the atmospheric circulation over the Atlantic and are coupled to changes in the Walker circulation. During the high phase of the simulated Southern Oscillation, conditions in the atmosphere and ocean are essentially the reverse of the low phase. The model produces a response in the South American region during the opposing phases of the Southern Oscillation that is in general agreement with observations. The interannual variation of Nordeste rainfall is shown to be dominated by a few band-limited frequencies. These frequencies are found in the SST series of those regions of the Atlantic and Pacific oceans where strong correlations with Nordeste precipitation exist. C1 LAWRENCE LIVERMORE NATL LAB,PROGRAM CLIMATE MODEL DIAG & INTERCOMPARISON,POB 808,LIVERMORE,CA 94551. SUNY STONY BROOK,INST TERR & PLANETARY ATMOSPHERES,STONY BROOK,NY 11794. RI Sperber, Kenneth/H-2333-2012 NR 40 TC 24 Z9 25 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD MAR PY 1993 VL 6 IS 3 BP 487 EP 498 DI 10.1175/1520-0442(1993)006<0487:TOTSOI>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA KY833 UT WOS:A1993KY83300005 ER PT J AU REED, BR JAGUST, WJ COULTER, L AF REED, BR JAGUST, WJ COULTER, L TI ANOSOGNOSIA IN ALZHEIMERS-DISEASE - RELATIONSHIPS TO DEPRESSION, COGNITIVE FUNCTION, AND CEREBRAL PERFUSION SO JOURNAL OF CLINICAL AND EXPERIMENTAL NEUROPSYCHOLOGY LA English DT Article ID POSITRON EMISSION TOMOGRAPHY; MAJOR DEPRESSION; CHOLINERGIC ABNORMALITIES; RIGHT-HEMISPHERE; MOOD DISORDERS; DEMENTIA; IMPAIRMENT; LESIONS; UNAWARENESS; ASYMMETRIES AB Awareness of memory loss was rated in 57 patients with clinically diagnosed Alzheimer's disease, and analyzed in relation to neuropsychological tests and presence of depression. Single photon emission computed tomography measures of regional cerebral blood flow were obtained on an unselected subsample of 20. Anosognosia was associated with diminished relative right dorsolateral frontal lobe perfusion and with high rates of false positive errors on recognition memory testing. Less aware patients did not differ from others on learning or recall scores, or on dementia severity as measured by mental status scores. Neither anosognosia nor depression was associated with disease duration or dementia severity and patients who were aware of their memory loss were no more likely than others to be depressed. This is further evidence that dementia severity alone does not account for anosognosia in Alzheimer's disease; frontal lobe involvement and the presence of specific memory impairments may be important determining factors. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CALIF DAVIS,SCH MED,DEPT NEUROL,DAVIS,CA 95616. FU NIA NIH HHS [AG07793] NR 50 TC 195 Z9 199 U1 1 U2 11 PU SWETS ZEITLINGER PUBLISHERS PI LISSE PA P O BOX 825, 2160 SZ LISSE, NETHERLANDS SN 1380-3395 J9 J CLIN EXP NEUROPSYC JI J. Clin. Exp. Neuropsychol. PD MAR PY 1993 VL 15 IS 2 BP 231 EP 244 DI 10.1080/01688639308402560 PG 14 WC Psychology, Clinical; Clinical Neurology; Psychology SC Psychology; Neurosciences & Neurology GA KX465 UT WOS:A1993KX46500008 PM 8491848 ER PT J AU CISZEK, TF WANG, TH BURROWS, RW WU, X AF CISZEK, TF WANG, TH BURROWS, RW WU, X TI GROWTH OF THIN CRYSTALLINE SILICON LAYERS FOR PHOTOVOLTAIC DEVICE USE SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 10TH INTERNATIONAL CONF ON CRYSTAL GROWTH ( ICCG-10 ) CY AUG 16-21, 1992 CL SAN DIEGO, CA SP INT UNION CRYSTAL GROWTH, AIRTRON, AKZO, ALLIED SIGNAL, BERTRAM LABS, CERES, CLEVELAND CRYSTALS, CRYSTAL ASSOC, CRYSTAL SYST, CRYSTAL TECHNOL AB Because of the current interest in thin-layer (5-50 mum) crystalline silicon for photovoltaic (PV) applications, we have grown Si layers on (111) single crystal Si substrates from the metal solvents Ga, Sn, and Cu with a particular emphasis on Cu. A substrate dipping technique was used, and the growth temperature was typically near 950-degrees-C. The conditions of growth, morphology, qualitative solvent incorporation characteristics, and electrical properties of the solution-grown layers are presented and discussed. Thin single crystal layers with suitable impurity characteristics for photovoltaic use were obtained, and solar cells with 15% conversion efficiency were fabricated on 5 mum thick layers grown on single crystal Si substrates. This is 97% of the efficiency obtained on substrates without a grown layer, and indicates that the Cu solution growth process does not significantly degrade cell performance. C1 GEN RES INST NONFERROUS MET,BEIJING,PEOPLES R CHINA. RP CISZEK, TF (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 7 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR PY 1993 VL 128 IS 1-4 BP 314 EP 318 DI 10.1016/0022-0248(93)90340-3 PN 1 PG 5 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KU915 UT WOS:A1993KU91500055 ER PT J AU KAMIMURA, Y TANAKA, T OTANI, S ISHIZAWA, Y REK, ZU WONG, J AF KAMIMURA, Y TANAKA, T OTANI, S ISHIZAWA, Y REK, ZU WONG, J TI FLOATING ZONE GROWTH OF MONOCHROMATOR GRADE CRYSTALS OF YB66 SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 10TH INTERNATIONAL CONF ON CRYSTAL GROWTH ( ICCG-10 ) CY AUG 16-21, 1992 CL SAN DIEGO, CA SP INT UNION CRYSTAL GROWTH, AIRTRON, AKZO, ALLIED SIGNAL, BERTRAM LABS, CERES, CLEVELAND CRYSTALS, CRYSTAL ASSOC, CRYSTAL SYST, CRYSTAL TECHNOL AB Monochromator grade crystals of YB66 have been grown by the indirect heating floating zone (IHFZ) method. For growth at the congruent composition of [B]/[Y] = 62, some high quality crystals have been obtained by keeping a convex growth interface through the crystal using a minimized heating power and downwards drive. Reproducible growth of monochromator grade crystals has been achieved by growing crystals under an incongruent condition where the compositions of the feed rod and the zone are about [B]/[Y] = 56 and 40, respectively. C1 NATL INST RES INORGAN MAT,1-1 NAMIKI,TSUKUBA,IBARAKI 305,JAPAN. STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94309. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. NR 6 TC 19 Z9 19 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 MAR PY 1993 VL 128 IS 1-4 BP 429 EP 434 DI 10.1016/0022-0248(93)90361-Y PN 1 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KU915 UT WOS:A1993KU91500076 ER PT J AU BIEFELD, RM AF BIEFELD, RM TI THE GROWTH OF INSB USING ALTERNATIVE ORGANOMETALLIC SB SOURCES SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 10TH INTERNATIONAL CONF ON CRYSTAL GROWTH ( ICCG-10 ) CY AUG 16-21, 1992 CL SAN DIEGO, CA SP INT UNION CRYSTAL GROWTH, AIRTRON, AKZO, ALLIED SIGNAL, BERTRAM LABS, CERES, CLEVELAND CRYSTALS, CRYSTAL ASSOC, CRYSTAL SYST, CRYSTAL TECHNOL ID CHEMICAL VAPOR-DEPOSITION; EPITAXIAL-GROWTH; PHASE EPITAXY; MOCVD; TRIISOPROPYLANTIMONY; GAAS AB The growth of InSb was investigated using triisopropylantimony (TIPSb) or tertiarybutyldimethylantimony (TBDMSb) and trimethylindium (TMIn) or triethylindium (TEIn) over a temperature range of 350 to 475-degrees-C and pressures between 200 and 600 Torr. The growth rates of InSb using TMIn or TEIn and either TIPSb or TBDMSb at temperatures less-than-or-equal-to 425-degrees-C were proportional to both the TMIn or TEIn flow rate and the temperature. The surface morphology of InSb grown using either TIPSb or TBDMSb and TMIn or TEIn was very rough for growth temperatures less-than-or-equal-to 425-degrees-C. The InSb with the highest mobility was grown at 400-degrees-C and a V/III ratio of 3 using TIPSb and TMIn. It was n-type with a carrier concentration of 2.5 x 10(15) cm-3 and a mobility of 78,160 cm2/V.s at 77 K. Both n- and p-type InSb were grown using TBDMSb with mobilities up to 67,530 and 7773 cm2/V.s respectively, at 77 K. Only p-type InSb could be grown using TEIn and TIPSb. The mobility for InSb using either TIPSb or TBDMSb and TMIn was optimized by reducing temperatures, pressures and V/III ratios. The opposite was true for surface morphology, which improved with higher temperature, pressure, and V/III ratio. The groWth of high mobility InSb with smooth surfaces at T less-than-or-equal-to 425-degrees-C was not achieved with TIPSb or TBDMSb and TMIn or TEIn for the growth conditions examined in this investigation. RP BIEFELD, RM (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 20 TC 4 Z9 4 U1 1 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 MAR PY 1993 VL 128 IS 1-4 BP 511 EP 515 DI 10.1016/0022-0248(93)90377-9 PN 1 PG 5 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KU915 UT WOS:A1993KU91500092 ER PT J AU KWAY, WL RUPP, B TASSANO, JB AF KWAY, WL RUPP, B TASSANO, JB TI CHARACTERIZATION OF THE LISR(AL,CR)F6 SOLID-SOLUTION FOR CR-LASER APPLICATIONS SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 10TH INTERNATIONAL CONF ON CRYSTAL GROWTH ( ICGG-10 ) CY AUG 16-21, 1992 CL SAN DIEGO, CA AB We have investigated the melting behavior, crystal structure, and laser characteristics of Czochralski grown or zone melted laser crystal materials in the psuedo-binary system LiSr(Al,Cr)F6. Congruent melting behavior and continuously increasing melting temperatures with increasing Cr substitution were determined by differential thermal analysis. X-ray data proved that the fluorides LiSrAl1-xCrxF6 form a continuous solid solution throughout the complete composition range (0 less-than-or-equal-to x less-than-or-equal-to 1), crystallizing in the trigonal LiCaAlF6-type structure (space group P11cBAR, No. 163, z = 2). In this structure type, Cr occupies distorted CrF6 octahedra with a Cr-F distance of about 1.90 angstrom. RP KWAY, WL (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 5508,L-250,LIVERMORE,CA 94551, USA. NR 8 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 MAR PY 1993 VL 128 IS 1-4 BP 1036 EP 1039 DI 10.1016/S0022-0248(07)80093-5 PN 2 PG 4 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KV697 UT WOS:A1993KV69700092 ER PT J AU KLEM, JF LOTT, JA SCHIRBER, JE KURTZ, SR LIN, SY AF KLEM, JF LOTT, JA SCHIRBER, JE KURTZ, SR LIN, SY TI STRAINED QUANTUM-WELL MODULATION-DOPED INGASB/ALGASB STRUCTURES GROWN BY MOLECULAR-BEAM EPITAXY SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE ALUMINUM GALLIUM ANTIMONIDE; FIELD-EFFECT TRANSISTORS; HOLE TRANSPORT ID FIELD-EFFECT TRANSISTORS; P-CHANNEL; HIGH-TRANSCONDUCTANCE AB Strained single quantum well InGaSb/AlGaSb structures for field-effect transistor applications have been grown by molecular beam epitaxy. Modulation-doped p-type structures have been characterized by a variety of techniques, including Hall effect, Shubnikov-de Haas measurements, and cyclotron resonance. These structures exhibit improved hole transport in comparison to similar GaSb/AlGaSb structures as a result of strain-splitting of the valence band. P-channel field-effect transistors fabricated in this system exhibited a maximum transconductance of 51 and 161 mS/mm at 300 and 77K, respectively, for a 1.2 mum gate-length device. C1 PRINCETON UNIV,PRINCETON,NJ 08544. RP KLEM, JF (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 15 TC 21 Z9 21 U1 0 U2 5 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAR PY 1993 VL 22 IS 3 BP 315 EP 321 DI 10.1007/BF02661383 PG 7 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA KR230 UT WOS:A1993KR23000009 ER PT J AU ATHAR, A SOMASUNDARAM, S TURNER, WD AF ATHAR, A SOMASUNDARAM, S TURNER, WD TI SYSTEM OPTIMIZATION OF THE COGENERATION FACILITY AT TEXAS A-AND-M UNIVERSITY - PRESENT OPERATION AND LOAD SO JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB The combined-cycle cogeneration facility on the central campus of Texas A&M University was analyzed for its present performance and an optimized mode of operation. The analysis was carried out using a plant Energy Optimization Program (EOP) that has been developed by Sega, Inc. The program uses Dither algorithms to match the energy demand and supply at each energy level (node), by choosing the lowest cost supplier among all the energy suppliers at the energy node. When this is done for all the energy nodes as the campus load varies throughout the year, one can determine the hourly and then the annual cost of operating the plant under both the existing and the optimized modes. The results were also compared with those obtained by using the Navy's Civil Engineering Laboratory Cogeneration Analysis Program (CELCAP), and the agreement was within 5 percent. Comparison with actual costs produced an agreement to within 1 percent. Finally, certain recommendations are made as to a more cost-efficient mode of operating the present facility. RP ATHAR, A (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 0 TC 0 Z9 0 U1 2 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0195-0738 J9 J ENERG RESOUR-ASME JI J. Energy Resour. Technol.-Trans. ASME PD MAR PY 1993 VL 115 IS 1 BP 17 EP 22 DI 10.1115/1.2905964 PG 6 WC Energy & Fuels SC Energy & Fuels GA KU130 UT WOS:A1993KU13000003 ER PT J AU TANG, Y AF TANG, Y TI DYNAMIC-RESPONSE OF TANK CONTAINING 2 LIQUIDS SO JOURNAL OF ENGINEERING MECHANICS-ASCE LA English DT Article AB A study on the dynamic response of upright circular cylindrical liquid-storage tanks containing two different liquids under a horizontal base motion with an arbitrary temporal variation is presented. Only rigid tanks were studied. The response functions examined include the base shear, base moments, and hydrodynamic pressure on the tank wall and base. Unlike the cases of tanks containing one liquid, in which the response is controlled by one parameter, height-to-radius ratio, the responses of tanks that contain two different liquids are controlled by three parameters: height-to-radius ratio, mass density ratio, and height ratio of the two liquids. The response functions are evaluated for a wide range of values for each parameter; the results are presented in graphic forms. The study shows that the dynamic response of a tank filled with two liquids is quite different from that of an identical tank filled with only one liquid; the maximum sloshing wave height may increase significantly, and the fundamental period of the sloshing motion is longer in a tank containing two liquids. RP TANG, Y (reprint author), ARGONNE NATL LAB,DIV REACTOR ENGN,ARGONNE,IL 60439, USA. NR 10 TC 11 Z9 11 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9399 J9 J ENG MECH-ASCE JI J. Eng. Mech.-ASCE PD MAR PY 1993 VL 119 IS 3 BP 531 EP 548 DI 10.1061/(ASCE)0733-9399(1993)119:3(531) PG 18 WC Engineering, Mechanical SC Engineering GA LQ776 UT WOS:A1993LQ77600006 ER PT J AU KUMARI, SS SKINNER, DM AF KUMARI, SS SKINNER, DM TI PROTEINS OF CRUSTACEAN EXOSKELETON .2. IMMUNOLOGICAL EVIDENCE FOR THEIR RELATEDNESS TO CUTICULAR PROTEINS OF 2 INSECTS SO JOURNAL OF EXPERIMENTAL ZOOLOGY LA English DT Article ID DIFFERENT ANATOMICAL REGIONS; LARVAL PUPAL TRANSFORMATION; CRAB GECARCINUS-LATERALIS; HYALOPHORA-CECROPIA; CUTICLE PROTEIN; TOBACCO HORNWORM; MANDUCA-SEXTA; LAND CRAB; DROSOPHILA-MELANOGASTER; POLYACRYLAMIDE GELS AB The exoskeletons of crustaceans and cuticles of insects are characterized by an abundance of proteins with acidic pIs and Ms 31 kDa or smaller. Immunochemical data described here further demonstrate the similarities of such proteins among representatives of these two major classes of Arthropoda. Proteins extracted from the four individual layers of the exoskeletons of Bermuda land crabs Gecarcinus lateralis at different stages of the intermolt cycle and from exuviae, the partially degraded old exoskeleton that is cast at ecdysis, were analyzed on Western blots with polyspecific polyclonal antibodies against either larval cuticular proteins (anti-LCP) or pupal cuticular proteins (anti-PCP) of the tobacco hornworm Manduca sexta, or against two pairs of larval cuticular proteins from third instar larvae (anti-L3CPS) of Drosophila melanogaster. M. sexta anti-LCP cross-reacted with many of the crab proteins extracted at all stages of the intermolt cycle. It reacted with more high M(r) proteins from late proecdysial exoskeleton and exuviae than with such proteins from anecdysial or early proecdysial exoskeletons, probably because the larger M, proteins are enriched when the lower M(r) proteins are degraded during proecdysis. M. sexta anti-PCP cross-reacted hardly at all with the crab proteins. Both D. melanogaster anti-L3CPS cross-reacted with crab epicuticular proteins at all stages of the intermolt cycle and from exuviae. Anti-L3CP 3 + 4 reacted even more intensely and with many more proteins from the three inner layers of the exoskeleton than did anti-L3CP 1 + 2. Controls included 2D gels with rabbit anti-ovalbumin to detect glycoproteins containing mannose and N-acetylglucosamine; it cross-reacted with only one protein in membranous layer of an anecdysial crab, while rabbit anti-fluorescein reacted with none. By contrast, the intensity and specificity of the cross-reactions of crab exoskeletal proteins with antibodies against cuticular proteins of members of two orders of insects suggest that at least some cuticular proteins in the two arthropod Classes, Crustacea and Insecta, are evolutionarily conserved. C1 OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. E TENNESSEE STATE UNIV,DEPT BIOPHYS,JOHNSON CITY,TN 37614. NR 57 TC 17 Z9 17 U1 0 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0022-104X J9 J EXP ZOOL JI J. Exp. Zool. PD MAR 1 PY 1993 VL 265 IS 3 BP 195 EP 210 DI 10.1002/jez.1402650302 PG 16 WC Zoology SC Zoology GA KP699 UT WOS:A1993KP69900001 ER PT J AU HWANG, CC ZHU, GX MASSOUDI, M EKMANN, JM AF HWANG, CC ZHU, GX MASSOUDI, M EKMANN, JM TI A COMPARISON OF THE LINEAR AND NONLINEAR K-EPSILON TURBULENCE MODELS IN COMBUSTORS SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID BACKWARD-FACING STEP; 2ND-ORDER FLUID; 2-EQUATION MODEL; CREEPING FLOW; SWIRL AB In swirling turbulent flows, the structure of turbulence is nonhomogeneous and anisotropic and it has been observed that the assumptions leading to the formulation of the k-epsilon model, which is used very often in many engineering applications, are inadequate for highly swirling flows. Furthermore, even with the various modifications made to the k-epsilon model, it is still not capable of describing secondary flows in noncircular ducts and it cannot predict non-zero normal-Reynolds-stress differences. Recently Speziale (1987) has developed a nonlinar k-epsilon model, which extends the range of validity of the standard k-epsilon model while maintaining most of the interesting features of the k-epsilon model; for example, the ease of application in existing Computational Fluid Dynamics (CFD) codes. In this work, we will use the nonlinear k-epsilon closure to model the turbulence in combustors. The particular combustor geometries selected for this study are (i) the flow in a round pipe entering an expansion into another coaxial round pipe, and (ii) the flow in two confined co-axial swirling jets. The results show that there are no significant differnces in the performance of the two models. It is speculated that the inlet conditions for k and epsilon may play as crucial a role in achieving predicted accuracy as turbulence modeling details. Also it is possible that weaknesses in the performance of the modeled equations for k and epsilon may have masked differences in the two models. C1 US DOE,PITTSBURGH ENERGY TECHNOL CTR,PITTSBURGH,PA 15236. RP HWANG, CC (reprint author), UNIV PITTSBURGH,DEPT MECH ENGN,PITTSBURGH,PA 15261, USA. NR 35 TC 7 Z9 7 U1 0 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD MAR PY 1993 VL 115 IS 1 BP 93 EP 102 DI 10.1115/1.2910119 PG 10 WC Engineering, Mechanical SC Engineering GA KV017 UT WOS:A1993KV01700015 ER PT J AU BOROVSKY, JE NEMZEK, RJ BELIAN, RD AF BOROVSKY, JE NEMZEK, RJ BELIAN, RD TI THE OCCURRENCE RATE OF MAGNETOSPHERIC-SUBSTORM ONSETS - RANDOM AND PERIODIC SUBSTORMS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ENERGETIC PARTICLE MEASUREMENTS; PROTON DRIFT ECHOES; GEOMAGNETIC-ACTIVITY; EXPANSIVE PHASE; PLASMA; ELECTROJET; SIGNATURE; DYNAMICS; 6.6-RE; CLOUDS AB Particle-injection events are monitored on three geosynchronous satellites to determine the occurrences of magnetospheric substorms: for every consecutive pair of substorms found, the time interval DELTAt between substorm onsets is determined. In this manner, 1001 values of DELTAt are obtained. A statistical analysis of the DELTAt values finds that the most-probable time between substorms onsets is DELTAt almost-equal-to 2.75 hours: this is interpreted to be the period between substorms when substorms occur cyclically. The statistical analysis of the DELTAt values also finds a random probability for the occurrence of substorms with a mean time between random substorms of about 5 hours: it is speculated that this random occurrence may be caused by a property of the solar wind that varies randomly with an approximately 5-hour time scale. About 1500 substorms occur per year: about half axe periodic and about half occur randomly. RP BOROVSKY, JE (reprint author), LOS ALAMOS NATL LAB,SPACE PLASMA PHYS GRP,LOS ALAMOS,NM 87545, USA. NR 58 TC 162 Z9 163 U1 1 U2 5 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 MAR 1 PY 1993 VL 98 IS A3 BP 3807 EP 3813 DI 10.1029/92JA02556 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KP929 UT WOS:A1993KP92900030 ER PT J AU MCKEAN, ME WINSKE, D THOMSEN, MF ONSAGER, TG AF MCKEAN, ME WINSKE, D THOMSEN, MF ONSAGER, TG TI NEAR-SPECULAR REFLECTION OF IONS AT QUASI-PARALLEL SHOCKS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID PERPENDICULAR BOW SHOCK; COLLISIONLESS SHOCKS; RE-FORMATION; SIMULATIONS; DISSIPATION; PLASMA; FOOT AB Previous numerical simulations have shown that ions are reflected at quasi-parallel shocks in a bursty manner. At times, relatively cold and dense beams of ions that appear to be specularly reflected are seen, consistent with observations at the quasi-parallel portions of the bow shock. The intermittent reflection of ions has been shown to be connected to the periodic disruption and re-formation of the shock front. Though the connection of the reflected ions to the re-formation cycle has been studied extensively, the reflection process itself has received little attention. Using one-dimensional hybrid simulations and a semianalytic model of the shock front, the reflection process is investigated to determine the source regions in incident ion phase space of reflected and transmitted ions, the relative importance of the electric and magnetic forces in the reflection of incident ions, and how these characteristics change in time. We find that the phase space origin of reflected particles and the fraction of incident ions that reflect depend upon the electromagnetic field structure of the shock front at the time the ions encounter it. The reflection fraction is maximized when the electric field along the shock normal (E(x)) and the noncoplanar magnetic field (B(y)) are at their maximum values. This happens because the phase space source region of reflected particles lies closer to the center of the incident ion distribution function when those two field components are large than it does when they are small. Also, when E(x) and B(y) are large, the reflection process produces a beam that is cooler, more dense, and closer to specular than when they are small. We also find that, in general, the electric field provides most of the force involved in the reflection of incident ions, although the magnetic field is also needed to reflect all but a few ions. When E(x) is near zero, almost no ions reflect in the shock ramp. C1 UNIV NEW HAMPSHIRE,INST STUDY EARTH OCEANS & SPACE,CTR SPACE SCI,DURHAM,NH 03824. LOS ALAMOS NATL LAB,DIV SPACE SCI & TECHNOL,LOS ALAMOS,NM 87545. RP MCKEAN, ME (reprint author), LOS ALAMOS NATL LAB,DIV APPL THEORET PHYS,LOS ALAMOS,NM 87545, USA. NR 33 TC 4 Z9 5 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 MAR 1 PY 1993 VL 98 IS A3 BP 3859 EP 3873 DI 10.1029/92JA02399 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KP929 UT WOS:A1993KP92900034 ER PT J AU THOMSEN, MF GOSLING, JT ONSAGER, TG RUSSELL, CT AF THOMSEN, MF GOSLING, JT ONSAGER, TG RUSSELL, CT TI ION AND ELECTRON HEATING AT THE LOW-MACH-NUMBER, QUASI-PARALLEL BOW SHOCK SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MULTIPLE SPACECRAFT OBSERVATIONS; COLLISIONLESS SHOCKS; INTERPLANETARY SHOCKS; REFLECTED IONS; SCALE LENGTHS; VELOCITY DISTRIBUTIONS; RE-FORMATION; SIMULATIONS; DOWNSTREAM; UPSTREAM AB The magnetic structure and energy dissipation at low-Mach-number, quasi-parallel collisionless shocks are examined through observations obtained by the ISEE 1 and 2 spacecraft at seven crossings of the Earth's dayside bow shock. The Alfven Mach number of the shocks in this set ranges from 2.0 to 3.7, and the angle theta(Bn) between the shock normal and the average upstream magnetic field direction ranges from 2-degrees to 39-degrees. The shocks all exhibit a fairly short-scale-length ramp where the principal jumps in the electron temperature, ion temperature, and magnetic field strength take place. Large-amplitude, low-frequency, transverse waves in the magnetic field axe present in and downstream from the ramp, with more modest waves upstream. The amplitude of the downstream waves is typically larger than can be accounted for by shock compression of the upstream waves. The electron heating represents about 6% of the dissipated bulk flow energy, consistent with observations in other parameter regimes, and suggesting that the dominant electron heating process is the same. The electron share of the dissipated energy appears to increase somewhat with increasing theta(Bn), and the ion share appears to decrease. Coherent reflection of incident ions does not appear to be very important for ion heating at these low Mach numbers, although a low level of reflection may contribute significantly to the generation of the large-amplitude waves. Finally, the downstream ion distributions do not show the strong variability previously interpreted as evidence for a cyclic re-formation process at higher-Mach-number, quasi-parallel shocks. It is possible that the low-Mach-number shocks axe re-forming but do not exhibit the downstream variability because of the relatively low levels of reflected ions. RP THOMSEN, MF (reprint author), LOS ALAMOS NATL LAB,MS D466,LOS ALAMOS,NM 87545, USA. OI Russell, Christopher/0000-0003-1639-8298 NR 44 TC 11 Z9 11 U1 0 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 MAR 1 PY 1993 VL 98 IS A3 BP 3875 EP 3888 DI 10.1029/92JA02560 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KP929 UT WOS:A1993KP92900035 ER PT J AU OKUDA, H AF OKUDA, H TI NUMERICAL-SIMULATION OF THE SUBSOLAR MAGNETOPAUSE CURRENT LAYER IN THE SUN-EARTH MERIDIAN PLANE SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID BOUNDARY-LAYER; RECONNECTION AB A two-dimensional electromagnetic particle simulation model was used to study formation and stability of the magnetopause current layer near the subsolar point in the Sun-Earth Meridian plane. Interactions of the dipole magnetic field with the unmagnetized and magnetized solar wind for both the southward and northward pointing interplanetary magnetic fields (IMF) are considered in the simulations. For the case of zero IMF the simulation results show that the current layer remains stable and is essentially the same as in the one-dimensional simulation. The width of the current layer is given by the electron-ion hybrid gyroradius which is much smaller than the ion gyroradius. This is in sharp contrast to our earlier two-dimensional simulations in the equatorial plane where the current layer is strongly unstable against the high-frequency drift waves. The current layer is found to remain stable for the northward IMF as well. As in the one-dimensional simulation, the jump of the magnetic field at the current layer for the northward IMF remains small. For the southward IMF, collisionless magnetic reconnection is found to develop, leading to formation of magnetic islands and density peaking within the current layer. At later times the coalescence of magnetic islands and the mixing of the plasma lead to a smooth density distribution in the magnetopause current layer, resulting in a current layer width of about 1 ion gyrodiameter. RP OKUDA, H (reprint author), PRINCETON UNIV,PLASMA PHYS LAB,POB 451,PRINCETON,NJ 08543, USA. NR 23 TC 6 Z9 6 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 MAR 1 PY 1993 VL 98 IS A3 BP 3953 EP 3962 DI 10.1029/92JA02535 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KP929 UT WOS:A1993KP92900041 ER PT J AU GARY, SP MCKEAN, ME WINSKE, D AF GARY, SP MCKEAN, ME WINSKE, D TI ION-CYCLOTRON ANISOTROPY INSTABILITIES IN THE MAGNETOSHEATH - THEORY AND SIMULATIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ELECTROMAGNETIC INSTABILITIES; 2ND-ORDER THEORY; MIRROR WAVES; DOWNSTREAM; SHOCKS; LAYER; BETA AB Recent observations and theoretical studies have established the importance of the tenuous helium ion component in determining instability growth and low-frequency magnetic fluctuation properties in the terrestrial magnetosheath. Under low-beta, high-ion-anisotropy sheath conditions, enhanced fluctuations observed below the proton cyclotron frequency have been attributed to the proton and helium cyclotron anisotropy instabilities. This paper uses second-order theory and one-dimensional hybrid computer simulations to examine the nonlinear properties of these two instabilities at relatively weak fluctuation levels and at propagation parallel to the background magnetic field. The simulations confirm the second-order predictions that both instabilities yield efficient wave-particle interactions; the rate at which the driving species anisotropy is reduced is much greater than the rate at which that species loses kinetic energy. This result suggests that these instabilities should saturate at relatively low levels; we derive an approximate expression for the fluctuating field energy at saturation of the fastest growing modes and find that it is in fair agreement with three computer simulations. In addition, second-order theory and simulations concur that the helium component enhances the wave-particle exchange rate for proton anisotropy reduction by the proton cyclotron instability; theory predicts and simulations confirm that the saturation energy of this mode is substantially lower than it is in the absence of helium. RP GARY, SP (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 27 TC 37 Z9 37 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 MAR 1 PY 1993 VL 98 IS A3 BP 3963 EP 3971 DI 10.1029/92JA02585 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KP929 UT WOS:A1993KP92900042 ER PT J AU MOSES, RW FINN, JM LING, KM AF MOSES, RW FINN, JM LING, KM TI PLASMA-HEATING BY COLLISIONLESS MAGNETIC RECONNECTION - ANALYSIS AND COMPUTATION SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID FIELD LINE RECONNECTION; GEOMAGNETIC TAIL; PARTICLE-ACCELERATION; CHAOTIC SCATTERING; TEARING MODE; RE-CONNEXION; X-POINTS; MAGNETOTAIL; CONDUCTIVITY; DYNAMICS AB This paper presents analytic and numerical results on particle acceleration in two-dimensional collisionless magnetic reconnection. The magnetic field is taken to be a vacuum quadrupole field in the x-y plane with no variation in the z direction. The electric field is uniform and in the z direction. Plasma particles are introduced with their guiding centers on a magnetic flux surface. Particles then execute E x B drift motion under which their guiding centers approach the separatrix. In the numerical simulations and in the analytic modeling presented, the particles are followed until they reach an outgoing flux surface at the same distance from the origin as the starting surface. The magnetic moment is not conserved for particles passing through the unmagnetized region around the X line at the origin. Other particles cross the separatrix without passing near the X line. The magnetic moment of the first class of outgoing particles is randomized, whereas it can be conserved for the second class. There is a consequent net change of particle kinetic energy for the first class of trajectories, which are accelerated by the electric field along the X line. The energy of the accelerated particles can have a ''fractal'' like dependence on trajectory initial conditions, characteristic of chaotic scattering, depending on the value of the electric field. By following the evolution of monoenergetic components of the input distribution function, it is possible to describe analytically this plasma thermalization process. The analytic model is based upon the observation of the final kinetic energy as a function of the initial conditions. Analytic results are shown which predict a Maxwellian tail for the distribution function in the perpendicular kinetic energy K(perpendicular-to) with K(perpendicular-to) >> K(parallel-to), the parallel kinetic energy. Numerical results are also presented, showing that the predicted tail temperature agrees with the numerically computed temperature to within 10% over 4 orders of magnitude in the electric field. These results provide a detailed understanding of particle acceleration and heating produced by collisionless magnetic reconnection. C1 UNIV MARYLAND,PLASMA RES LAB,COLL PK,MD 20742. RP MOSES, RW (reprint author), LOS ALAMOS NATL LAB,SST-7,MAIL STOP D466,LOS ALAMOS,NM 87545, USA. NR 67 TC 36 Z9 36 U1 2 U2 3 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 MAR 1 PY 1993 VL 98 IS A3 BP 4013 EP 4040 DI 10.1029/92JA02267 PG 28 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KP929 UT WOS:A1993KP92900047 ER PT J AU EISLER, GR HULL, DG AF EISLER, GR HULL, DG TI GUIDANCE LAW FOR PLANAR HYPERSONIC DESCENT TO A POINT SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Note C1 UNIV TEXAS,DEPT AEROSP ENGN,AUSTIN,TX 78712. RP EISLER, GR (reprint author), SANDIA NATL LABS,DIV STRUCT DYNAM 1434,ALBUQUERQUE,NM 87185, USA. NR 7 TC 4 Z9 4 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAR-APR PY 1993 VL 16 IS 2 BP 400 EP 402 DI 10.2514/3.21020 PG 3 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA KR254 UT WOS:A1993KR25400028 ER PT J AU BURKE, VJ NAGLE, RD OSENTOSKI, M CONGDON, JD AF BURKE, VJ NAGLE, RD OSENTOSKI, M CONGDON, JD TI COMMON SNAPPING TURTLES ASSOCIATED WITH ANT MOUNDS SO JOURNAL OF HERPETOLOGY LA English DT Note ID CHELYDRA-SERPENTINA; SOUTHEASTERN C1 SAVANNAH RIVER ECOL LAB,AIKEN,SC 29802. E CAROLINA UNIV,DEPT BIOL,GREENVILLE,NC 27858. RP BURKE, VJ (reprint author), UNIV GEORGIA,DEPT ZOOL,ATHENS,GA 30602, USA. NR 7 TC 1 Z9 1 U1 0 U2 4 PU SOC STUD AMPHIBIANS REPTILES PI OXFORD PA DEPT OF ZOOLOGY MIAMI UNIV, OXFORD, OH 45056 SN 0022-1511 J9 J HERPETOL JI J. Herpetol. PD MAR PY 1993 VL 27 IS 1 BP 114 EP 115 DI 10.2307/1564921 PG 2 WC Zoology SC Zoology GA KU089 UT WOS:A1993KU08900025 ER PT J AU SULLIVAN, TS STEINBERG, V ECKE, RE AF SULLIVAN, TS STEINBERG, V ECKE, RE TI THERMAL-CONVECTION AND THERMAL-CONDUCTIVITY OF NONDILUTE HE-3-HE-4 MIXTURES SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article ID RAYLEIGH-BENARD CONVECTION; LOW-PRANDTL-NUMBER; PATTERN DYNAMICS; INSTABILITY; CONTAINERS; THRESHOLD; HE-3 AB We present measurements of the critical temperature difference for the onset of thermal convection and the effective thermal conductivity in two He-3-superfluid-He-4 mixtures. The mixtures were 6.8% and 9.8% by molar volume of He-3 in He-4 and the measurements were made from 0.65 K to just above the superfluid transition temperature for each mixture. The measurements were made as part of an effort to visualize convective flow patterns in helium mixtures using optical shadowgraph techniques. We discuss the implications of our results for this effort. C1 KENYON COLL,DEPT PHYS,GAMBIER,OH 43022. WEIZMANN INST SCI,DEPT NUCL PHYS,IL-76100 REHOVOT,ISRAEL. LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP SULLIVAN, TS (reprint author), LOS ALAMOS NATL LAB,DIV PHYS,LOS ALAMOS,NM 87545, USA. RI Steinberg, Victor/B-3205-2009 NR 38 TC 12 Z9 12 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 MAR PY 1993 VL 90 IS 5-6 BP 343 EP 354 DI 10.1007/BF00681886 PG 12 WC Physics, Applied; Physics, Condensed Matter SC Physics GA KW515 UT WOS:A1993KW51500002 ER PT J AU WU, Y PENG, ZY OLEJNICZAK, Z SUN, BQ PINES, A AF WU, Y PENG, ZY OLEJNICZAK, Z SUN, BQ PINES, A TI EFFECTS OF DOUBLE ROTATION ON HOMONUCLEAR SPIN SYSTEMS SO JOURNAL OF MAGNETIC RESONANCE SERIES A LA English DT Article ID DOUBLE-ROTOR; NMR; SOLIDS C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CALIF BERKELEY,BERKELEY,CA 94720. NR 13 TC 5 Z9 5 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 1064-1858 J9 J MAGN RESON SER A JI J. Magn. Reson. Ser. A PD MAR PY 1993 VL 102 IS 1 BP 29 EP 33 DI 10.1006/jmra.1993.1064 PG 5 WC Physics, Atomic, Molecular & Chemical SC Physics GA KZ354 UT WOS:A1993KZ35400005 ER PT J AU CLEMENS, BM OSGOOD, R PAYNE, AP LAIRSON, BM BRENNAN, S WHITE, RL NIX, WD AF CLEMENS, BM OSGOOD, R PAYNE, AP LAIRSON, BM BRENNAN, S WHITE, RL NIX, WD TI INSITU OBSERVATION OF ANISOTROPIC STRAIN RELAXATION IN EPITAXIAL FE (110) FILMS ON MO (110) SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT INTERNATIONAL SYMP ON MAGNETIC ULTRA THIN FILMS, MULTILAYERS AND SURFACES CY SEP 07-10, 1992 CL ECOLE NORMALE SUPER LYON, LYON, FRANCE SP EUROPEAN MAT RES SOC, MAT RES SOC, CNRS, PHILIPS RES, RIBER, SAGEM, TDK, LCR THOMSON CSF, TOSHIBA, UBE IND HO ECOLE NORMALE SUPER LYON ID ULTRATHIN FILMS; W(110); FE(110); MAGNETIZATION AB In-situ grazing incidence X-ray diffraction was used to measure the lattice parameter as a function of thickness for epitaxial Fe (110) films on Mo (110). A large, thickness-dependent, anisotropic in-plane strain was observed. This strain behavior is explained with an equilibrium misfit dislocation model incorporating anisotropic elasticity. The magnetostrictive anisotropy expected from this strain has nearly linear behavior in reciprocal film thickness and thus could be mistaken for a surface anisotropy. C1 STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94309. RP CLEMENS, BM (reprint author), STANFORD UNIV,DEPT MAT SCI & ENGN,STANFORD,CA 94305, USA. NR 19 TC 34 Z9 34 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD MAR PY 1993 VL 121 IS 1-3 BP 37 EP 41 DI 10.1016/0304-8853(93)91143-U PG 5 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA LA577 UT WOS:A1993LA57700007 ER PT J AU FELCHER, GP HUANG, YY CAREY, M BERKOWITZ, A AF FELCHER, GP HUANG, YY CAREY, M BERKOWITZ, A TI POLARIZED NEUTRON REFLECTION STUDY OF THE UNIDIRECTIONAL MAGNETIC-ANISOTROPY OF PERMALLOY ON NI0.5CO0.5O SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT INTERNATIONAL SYMP ON MAGNETIC ULTRA THIN FILMS, MULTILAYERS AND SURFACES CY SEP 07-10, 1992 CL ECOLE NORMALE SUPER LYON, LYON, FRANCE SP EUROPEAN MAT RES SOC, MAT RES SOC, CNRS, PHILIPS RES, RIBER, SAGEM, TDK, LCR THOMSON CSF, TOSHIBA, UBE IND HO ECOLE NORMALE SUPER LYON AB Couples of ferromagnetic Permalloy/antiferromagnetic metal oxide exhibit unidirectional magnetic anisotropy along a magnetic field applied during cooling. Polarized neutron reflection has been used to check if the effect is due to a bias of the antiferromagnetic configuration in the oxide, where the layer immediately adjacent to the Permalloy is polarized parallel to the easy direction of magnetization. The measurements were made on a sample consisting of 300 angstrom Permalloy/500 angstrom Ni0.5Co0.5O. Polarized neutron reflectivities were taken at the four corners of the magnetic hysteresis loop at 20 K. A faint magnetic signal consistent with the unidirectional bias of the F/AF structure was observed. This behavior is discussed in the light of the current theories. C1 UNIV CALIF SAN DIEGO,CTR MAGNET RECORDING RES,LA JOLLA,CA 92093. RP FELCHER, GP (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 9 TC 13 Z9 13 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD MAR PY 1993 VL 121 IS 1-3 BP 105 EP 108 DI 10.1016/0304-8853(93)91159-5 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA LA577 UT WOS:A1993LA57700023 ER PT J AU LOEWENHAUPT, M HAHN, W HUANG, YY FELCHER, GP PARKIN, SSP AF LOEWENHAUPT, M HAHN, W HUANG, YY FELCHER, GP PARKIN, SSP TI SPIN STRUCTURES OF FE/GD AND FE/CR MULTILAYERS DETERMINED BY POLARIZED NEUTRON REFLECTOMETRY SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article ID MAGNETIC SUPERLATTICES; PHASE-TRANSITIONS; FE LAYERS; MAGNETORESISTANCE; FERRIMAGNET; CO/RU AB Polarized neutron reflection was used to determine the magnetic structure of two different antiferromagnetically coupled multilayer systems, Fe/Gd and Fe/Cr. In Fe/Gd, the Fe and Gd moments are coupled antiparallel at the interface. At low temperatures a surface-induced magnetic phase transition was found. In Fe/Cr, annealing at temperatures of up to 425-degrees-C resulted in the degrading of antiferromagnetic coupling between Fe layers and in the formation of ferromagnetically coupled regions. C1 ARGONNE NATL LAB, DIV MAT SCI, ARGONNE, IL 60439 USA. IBM CORP, ALMADEN RES CTR, SAN JOSE, CA 95120 USA. RP LOEWENHAUPT, M (reprint author), FORSCHUNGSZENTRUM JULICH, INST FESTKORPERFORSCH, POSTFACH 1913, W-5170 JULICH 1, GERMANY. RI Parkin, Stuart/D-2521-2012 NR 13 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD MAR PY 1993 VL 121 IS 1-3 BP 173 EP 176 DI 10.1016/0304-8853(93)91178-A PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA LA577 UT WOS:A1993LA57700042 ER PT J AU FALICOV, LM HOOD, RQ AF FALICOV, LM HOOD, RQ TI A BOLTZMANN-EQUATION APPROACH TO THE MAGNETORESISTANCE OF FERROMAGNETIC NORMAL METALLIC MULTILAYERS SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT INTERNATIONAL SYMP ON MAGNETIC ULTRA THIN FILMS, MULTILAYERS AND SURFACES CY SEP 07-10, 1992 CL ECOLE NORMALE SUPER LYON, LYON, FRANCE SP EUROPEAN MAT RES SOC, MAT RES SOC, CNRS, PHILIPS RES, RIBER, SAGEM, TDK, LCR THOMSON CSF, TOSHIBA, UBE IND HO ECOLE NORMALE SUPER LYON ID GIANT MAGNETORESISTANCE; SUPERLATTICES; FE/CR AB The Boltzmann equation is solved for a ferromagnetic-normal-ferromagnetic metallic trilayer. The in-plane conductance of the film is calculated for two configurations: the ferromagnetic layers aligned (i) parallel and (ii) antiparallel to each other. The results explain the giant negative magnetoresistance encountered in multilayer systems. Considerable asymmetry in the interface scattering for the two spin orientations is required. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP FALICOV, LM (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. NR 20 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD MAR PY 1993 VL 121 IS 1-3 BP 362 EP 365 DI 10.1016/0304-8853(93)91221-R PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA LA577 UT WOS:A1993LA57700086 ER PT J AU DEVLIN, E PSYCHARIS, V KOSTIKAS, A SIMOPOULOS, A NIARCHOS, D JANKOWSKI, A TSAKALAKOS, T WAN, H HADJIPANAYIS, G AF DEVLIN, E PSYCHARIS, V KOSTIKAS, A SIMOPOULOS, A NIARCHOS, D JANKOWSKI, A TSAKALAKOS, T WAN, H HADJIPANAYIS, G TI STRUCTURE AND MAGNETIC-ANISOTROPY OF FE/PT MULTILAYERS SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT 5TH INTERNATIONAL CONF ON MAGNETIC RECORDING MEDIA ( MRM 92 ) CY SEP 02-04, 1992 CL PERUGIA, ITALY AB A series of Fe/Pt multilayers prepared by magnetron sputtering have been studied by XRD, conversion electron Mossbauer spectroscopy (CEMS) and SQUID magnetometry. The samples with individual Fe thickness of 3 angstrom show orientation of the magnetic moment close to perpendicular to the film plane and Curie temperatures near 350 K. Interdiffusion at the interface is manifested in a distribution of hyperfine fields. C1 NCSR DEMOKRITOS,INST MAT SCI,GR-15310 ATHENS,GREECE. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RUTGERS STATE UNIV,DEPT MECH & MAT SCI,PISCATAWAY,NJ 08855. UNIV DELAWARE,DEPT PHYS & ASTRON,NEWARK,DE 19716. OI NIARCHOS, DIMITRIOS/0000-0002-6256-7497 NR 6 TC 12 Z9 12 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD MAR PY 1993 VL 120 IS 1-3 BP 236 EP 238 DI 10.1016/0304-8853(93)91331-Z PG 3 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA KV224 UT WOS:A1993KV22400059 ER PT J AU ZHANG, JG EKLUND, PC AF ZHANG, JG EKLUND, PC TI FILAMENT FORMATION IN SWITCHING DEVICES BASED ON V2O5 GEL FILMS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article AB Filament formation in V2O5 gel films leading to a two-terminal switching device has been observed. In a previous paper, we have identified the switching with a metal-insulator transition within a permanent, current-induced channel between the electrical contacts. Here, we describe the reversible formation of a filament inside the channel, and obtain a static solution of the heat transport equation for this device which indicates a large temperature variation within the filament, and further reveals the failure mechanism for the reversible switching. The principle of least entropy production has been used to analyze the filament growth, which results in a successful simulation of the ''on'' state I-V characteristic of the switching process, including its negative resistance region. C1 UNIV KENTUCKY,CTR APPL ENERGY RES,LEXINGTON,KY 40506. UNIV KENTUCKY,DEPT PHYS & ASTRON,LEXINGTON,KY 40506. RP ZHANG, JG (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 20 TC 5 Z9 5 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 MAR PY 1993 VL 8 IS 3 BP 558 EP 564 DI 10.1557/JMR.1993.0558 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA KQ748 UT WOS:A1993KQ74800019 ER PT J AU UNAL, O PETROVIC, JJ MITCHELL, TE AF UNAL, O PETROVIC, JJ MITCHELL, TE TI MECHANICAL-PROPERTIES OF HOT ISOSTATICALLY PRESSED SI3N4 AND SI3N4/SIC COMPOSITES SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID SILICON-NITRIDE; FRACTURE-TOUGHNESS; MATRIX COMPOSITES; BEHAVIOR; ADDITIVES; CARBIDE AB The mechanical properties of hot isostatically pressed monolithic Si3N4 and Si3N4-20 vol. % SiC composites have been studied by microindentation at temperatures up to 1400-degrees-C. Indentation crack patterns and microstructures have been examined by optical microscopy, scanning electron microscopy, and transmission electron microscopy. It is shown that dense Si3N4 base materials can be synthesized by HIPing without densification aids. Both the monolithic Si3N4 and the Si3N4/SiC composites exhibit high hardness values which gradually decrease with increasing temperature. Both types of material show low fracture toughness values apparently because of strong interfacial bonding. On the other hand, the fracture toughness of the composite is about 40% higher than that of the monolithic material, due to the presence of the 20 vol. % SiC whiskers. A crack deflection/debonding mechanism is likely to be responsible for the higher toughness observed in the composite. High resolution electron microscopy shows that the grain boundaries in both samples contain a thin SiO2 layer. C1 LOS ALAMOS NATL LAB,CTR MAT SCI,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,DIV MAT SCI & TECHNOL,LOS ALAMOS,NM 87545. NR 23 TC 19 Z9 19 U1 2 U2 4 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 MAR PY 1993 VL 8 IS 3 BP 626 EP 634 DI 10.1557/JMR.1993.0626 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA KQ748 UT WOS:A1993KQ74800026 ER PT J AU CUNNINGHAM, ME FRESHLEY, MD LANNING, DD AF CUNNINGHAM, ME FRESHLEY, MD LANNING, DD TI FISSION-GAS RELEASE DURING POWER BUMPING AT HIGH BURNUP SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article AB Research to define the behavior of Zircaloy-clad light-water reactor fuel irradiated to high burnup levels was conducted by the High Burnup Effects Program (HBEP). One activity conducted by the HBEP was to ''bump'' the power level of irradiated, commercial light-water reactor fuel rods to design limit linear heat generation rates at end-of-life. These bumping irradiations simulated end-of-life design limit linear heat generation rates and provided data on the effects of short-term, high power irradiations at high burnup applicable to the design and operating constraints imposed by maximum allowable fuel rod internal gas pressure limits. Based on net fission gas release during the bumping irradiations, it was observed that higher burnup rods had greater rod-average fractional fission gas release than lower burnup rods at equal bumping powers. It was also observed that a hold period of 48 hours at the peak power was insufficient to achieve equilibrium fission gas release. Finally, differences in the prebump location of fission gas, i.e., within the UO2 matrix or at grain boundaries, affected the fission gas release during the bumping irradiations. RP CUNNINGHAM, ME (reprint author), PACIFIC NW LAB, POB 999, RICHLAND, WA 99352 USA. NR 9 TC 9 Z9 9 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 1993 VL 200 IS 1 BP 24 EP 40 DI 10.1016/0022-3115(93)90006-K PG 17 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA KR253 UT WOS:A1993KR25300005 ER PT J AU MAZIASZ, PJ AF MAZIASZ, PJ TI VOID SWELLING RESISTANCE OF PHOSPHORUS-MODIFIED AUSTENITIC STAINLESS-STEELS DURING HFIR IRRADIATION AT 300-500-DEGREES-C TO 57-DPA SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID ALLOYS; PRECIPITATION; BEHAVIOR; METALS; CREEP; CR AB The austenitic stainless steel prime candidate alloy (PCA) is a Ti-modified alloy (14Cr-16Ni) developed for void swelling resistance at 400-600-degrees-C by the US Fusion Reactor Materials (FMR) program. During irradiation in the High Flux Isotope Reactor (HFIR) to 34 and 57 dpa (70-75 appm He/dpa) at 300-600-degrees-C, the PCA (and the closely related D9 type alloy) has been shown to be highly susceptible to void swelling at 500-degrees-C. Generally such alloys show good void swelling resistance to higher doses during irradiation in fast-breeder reactors (FBRs, 0.5-1 appm He/dpa) in the 20-25% cold-worked (CW) condition. New multiply-stabilized, phosphorus-modified PCA alloys have been developed, with specific amounts and combinations of minor alloy elements added for improved MC formation and stability characteristics during irradiation. After HFIR irradiation at 300-500-degrees-C to 34-57 dpa, the multiply-stabilized, phosphorus-modified PCA and phosphorus-modified D9 alloy showed better swelling resistance (by density-change measurements) than similar alloys without phosphorus, particularly at 500-degrees-C. Microstructural studies after 34 dpa at 500-degrees-C showed that void swelling resistance in the multiply-stabilized, phosphorus-modified PCA alloys was directly related to the formation of ultrafine dispersions of MC precipitates during HFIR irradiation. RP MAZIASZ, PJ (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,POB 2008,OAK RIDGE,TN 37831, USA. NR 51 TC 18 Z9 18 U1 2 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 MAR PY 1993 VL 200 IS 1 BP 90 EP 107 DI 10.1016/0022-3115(93)90013-O PG 18 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA KR253 UT WOS:A1993KR25300012 ER PT J AU SMITH, HD BALDWIN, DL AF SMITH, HD BALDWIN, DL TI AN INVESTIGATION OF THERMAL RELEASE OF C-14 FROM PWR ZIRCALOY SPENT FUEL CLADDING SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article AB An investigation to study the thermally-activated release of carbon-14 from irradiated PWR Zircaloy spent fuel cladding to potential repository environments for the Yucca Mountain Site Characterization Project was performed. Experimental parameters included release temperature, atmosphere and oxide thickness. Thirteen experiments measuring carbon-14 release from irradiated Zircaloy-4 cladding samples with thin pretransition and thicker posttransition oxide films were completed. Experiments were performed in air at 373, 473, 548, and 623 K, for up to 24 h and in argon at 623 K for 8 h. The data were examined using classical diffusion models, diffusion from a semiinfinite plane and diffusion from a finite thickness plane. Diffusion coefficients were calculated at each of the four temperatures in air and for both the pre- and posttransition oxide cladding. The diffusion coefficients measured ranged from 1 x 10(-19) to 8 x 10(-14) m2/s with activation energies from 78-103 kJ/mol in the temperature range of 373-623 K. The data indicate that carbon-14 is released primarily from the oxide layer on these cladding samples. RP SMITH, HD (reprint author), PACIFIC NW LAB, POB 999, P7-14, RICHLAND, WA 99352 USA. NR 12 TC 6 Z9 6 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 1993 VL 200 IS 1 BP 128 EP 137 DI 10.1016/0022-3115(93)90016-R PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA KR253 UT WOS:A1993KR25300015 ER PT J AU LIBURDY, RP SLOMA, TR SOKOLIC, R YASWEN, P AF LIBURDY, RP SLOMA, TR SOKOLIC, R YASWEN, P TI ELF MAGNETIC-FIELDS, BREAST-CANCER, AND MELATONIN - 60 HZ FIELDS BLOCK MELATONINS ONCOSTATIC ACTION ON ER+ BREAST-CANCER CELL-PROLIFERATION SO JOURNAL OF PINEAL RESEARCH LA English DT Article DE MELATONIN; BREAST CANCER; MCF-7 CELLS; 60 HZ MAGNETIC FIELDS ID PINEAL HORMONE MELATONIN; ELECTROMAGNETIC-FIELDS; CULTURE; MCF-7; GLAND AB In this study we investigated whether a 60 Hz magnetic field can act at the cellular level to influence the growth of human estrogen-dependent breast cancer cells. Our experimental design assessed cell proliferation of a human breast cancer cell line, MCF-7, in the absence or the presence of melatonin which inhibits growth at a physiological concentration of 10(-9) M. In three experiments. continuous exposure to average sinusoidal 60 Hz magnetic fields of 1.90 +/- 0.01, 2.40 +/- 0.70, and 2.53 +/- 0.50 mG, or simultaneous exposure in matched incubators to average 60 Hz magnetic fields of 10.4 +/- 2.12, 11.95 +/- 2.73, and 11.95 +/- 3.28 mG, respectively, had no effect on cell proliferation in the absence of melatonin. When MCF-7 cells were cultured in the presence of 10(-9) M melatonin, an 18% inhibition of growth was observed for cells in a 2.40 +/- 0.70 mG field. This effect was blocked by a 60 Hz magnetic field of 11.95 +/- 2.75 mG. In a second experiment, a 27% inhibition of MCF-7 cell growth was observed for cells in a 2.53 +/- 0.50 mG magnetic field, and this was blocked by a 60 Hz magnetic field of 11.95 +/- 3.28 mG. These results provide the first evidence that ELF frequency magnetic fields can act at the cellular level to enhance breast cancer cell proliferation by blocking melatonin's natural oncostatic action. In addition, there appears to be a dose threshold between 2 and 12 mG. The mechanism(s) of action is unknown and may involve modulation of signal transduction events associated with melatonin's regulation of cell growth. RP LIBURDY, RP (reprint author), LAWRENCE BERKELEY LAB,DEPT CELL & MOLEC BIOL,DIV LIFE SCI,BIOELECTROMAGNET RES FACIL,BLDG 74,BERKELEY,CA 94720, USA. RI Sokolic, Robert/I-6072-2012 NR 24 TC 152 Z9 159 U1 1 U2 5 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0742-3098 J9 J PINEAL RES JI J. Pineal Res. PD MAR PY 1993 VL 14 IS 2 BP 89 EP 97 DI 10.1111/j.1600-079X.1993.tb00491.x PG 9 WC Endocrinology & Metabolism; Neurosciences; Physiology SC Endocrinology & Metabolism; Neurosciences & Neurology; Physiology GA LC752 UT WOS:A1993LC75200007 PM 8320637 ER PT J AU SMITH, MW JARRETT, O ANTCLIFF, RR NORTHAM, GB CUTLER, AD TAYLOR, DJ AF SMITH, MW JARRETT, O ANTCLIFF, RR NORTHAM, GB CUTLER, AD TAYLOR, DJ TI COHERENT ANTI-STOKES-RAMAN SPECTROSCOPY TEMPERATURE-MEASUREMENTS IN A HYDROGEN-FUELED SUPERSONIC COMBUSTOR SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB Coherent anti-Stokes Raman spectroscopy (CARS) thermometry has been used to obtain static temperature cross sections in a three-dimensional supersonic combustor flowfield. Data were obtained in three spanwise planes downstream of a single normal fuel injector which was located downstream of a rearward-facing step. The freestream flow was nominally Mach 2 and was combustion heated to a total temperature of 1440 K (yielding a static temperature of about 800 K in the freestream) to simulate the inflow to a combustor operating at a flight Mach number of about 5.4. Since a broadband probe laser was used an instantaneous temperature sample was obtained with each laser shot at a repetition rate of 10 Hz. Thus root-mean-square (rms) temperatures and temperature probability density functions (pdf's) were obtained in addition to mean temperatures. C1 NASA,LANGLEY RES CTR,DIV INSTRUMENT RES,OPT SPECT SECT,HAMPTON,VA 23681. GEORGE WASHINGTON UNIV,HAMPTON,VA 23681. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP SMITH, MW (reprint author), NASA,LANGLEY RES CTR,EXPTL METHODS BRANCH,COMBUST FUNDAMENTALS GRP,HAMPTON,VA 23681, USA. NR 6 TC 10 Z9 10 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 1993 VL 9 IS 2 BP 163 EP 168 DI 10.2514/3.23604 PG 6 WC Engineering, Aerospace SC Engineering GA KR542 UT WOS:A1993KR54200002 ER PT J AU WILSON, BG AF WILSON, BG TI EVALUATING ORBITAL OCCUPATION NUMBER CORRELATIONS IN HIGH-TEMPERATURE PLASMAS SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID DENSE-PLASMAS; HOT; ABSORPTION; OPACITY; MODELS; MEDIA AB We describe a method for calculating quantum statistical properties of hot ions in a plasma with the electrons treated beyond the independent particle approximation. The grand partition function, as well as other ensemble average quantities such as mean orbital occupancies and orbital occupation correlations, are given by exact integral expressions that can be evaluated by standard numerical techniques. Analytic approximations to the quadratures are obtained by employing a multi-variate Gaussian integration about the saddle point of the integrand. Illustrative numerical results are presented, and methods for estimating the error in computed quantities are discussed. RP WILSON, BG (reprint author), LAWRENCE LIVERMORE NATL LAB,L-59,POB 808,LIVERMORE,CA 94550, USA. NR 46 TC 12 Z9 12 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD MAR PY 1993 VL 49 IS 3 BP 241 EP 258 DI 10.1016/0022-4073(93)90086-W PG 18 WC Optics; Spectroscopy SC Optics; Spectroscopy GA KQ742 UT WOS:A1993KQ74200004 ER PT J AU NARAYANAN, VA BEGUN, GM STUMP, NA STOKES, DL DINH, TV AF NARAYANAN, VA BEGUN, GM STUMP, NA STOKES, DL DINH, TV TI VIBRATIONAL-SPECTRA OF FLUVALINATE SO JOURNAL OF RAMAN SPECTROSCOPY LA English DT Article ID ENHANCED RAMAN SPECTROMETRY; P-AMINOBENZOIC ACID; SCATTERING ANALYSIS AB The normal Raman spectrum (NRS), Fourier transform infrared spectrum (FTIRS) and surface-enhanced Raman spectrum (SERS) of the important insecticide and acaricide fluvalinate (C26H22ClF3N2O3) were recorded for the first time. The spectral data are discussed in terms of characteristic chemical group frequencies and bonds. The fingerprint regions of fluvalinate vibrations that are distinct in FTIRS are identified and presented with the different fingerprint frequencies that are only characteristic to NRS. The enhancement of the benzene ring-breathing vibration of fluvalinate in SERS is a useful mode for trace analysis for residues of this pesticide at the sub-nanogram level. The vibrational spectra and polarization characteristics of NRS frequencies are useful as reference spectra for this pesticide in the qualitative analysis of its residues. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. NR 36 TC 5 Z9 5 U1 2 U2 7 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0377-0486 J9 J RAMAN SPECTROSC JI J. Raman Spectrosc. PD MAR PY 1993 VL 24 IS 3 BP 123 EP 128 DI 10.1002/jrs.1250240302 PG 6 WC Spectroscopy SC Spectroscopy GA KU484 UT WOS:A1993KU48400001 ER PT J AU DOSS, ED GEYER, HK AF DOSS, ED GEYER, HK TI MHD SEAWATER PROPULSION SO JOURNAL OF SHIP RESEARCH LA English DT Article AB This paper discusses the reasons for the renewed interest in the concept of magnetohydrodynamic (MHD) seawater propulsion. The main advantages of this concept are presented, together with some of the technical challenges that need to be overcome to achieve reliability and performance. The paper discusses in simple terms some of the technical issues and loss mechanisms influencing the thruster performance in terms of its electrical efficiency. These issues include the jet losses and nozzle efficiency, Ohmic losses, frictional losses, three-dimensional effects and electrolysis inside the thruster. Furthermore, a parametric study has been performed using a developed two-dimensional model to investigate the effects of electrical end losses, the magnetic field, thruster diameter, wall roughness, flow velocity, and electrical load factor on the thruster performance. These studies show that the frictional and end losses can have strong adverse effects on the thruster performance and that the thruster efficiency increases with the strength of the magnetic field and thruster diameter and decreases with the wall roughness and the flow velocity. RP DOSS, ED (reprint author), ARGONNE NATL LAB,DIV ENGN PHYS,ARGONNE,IL 60439, USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU SOC NAVAL ARCH MARINE ENG PI JERSEY CITY PA 601 PAVONIA AVENUE, JERSEY CITY, NJ 07306 SN 0022-4502 J9 J SHIP RES JI J. Ship Res. PD MAR PY 1993 VL 37 IS 1 BP 49 EP 57 PG 9 WC Engineering, Marine; Engineering, Civil SC Engineering GA KT380 UT WOS:A1993KT38000007 ER PT J AU LEE, JY SWINNEA, JS STEINFINK, H REIFF, WM PEI, S JORGENSEN, JD AF LEE, JY SWINNEA, JS STEINFINK, H REIFF, WM PEI, S JORGENSEN, JD TI THE CRYSTAL-CHEMISTRY AND PHYSICAL-PROPERTIES OF THE TRIPLE LAYER PEROVSKITE INTERGROWTHS LASR3FE3O10-DELTA AND LASR3(FE3-XALX)O10-DELTA SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID REFINEMENT C1 NORTHEASTERN UNIV, DEPT CHEM, BOSTON, MA 02115 USA. ARGONNE NATL LAB, ARGONNE, IL 60439 USA. RP UNIV TEXAS, DEPT CHEM ENGN, AUSTIN, TX 78712 USA. NR 27 TC 46 Z9 47 U1 3 U2 24 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 MAR PY 1993 VL 103 IS 1 BP 1 EP 15 DI 10.1006/jssc.1993.1072 PG 15 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA KV216 UT WOS:A1993KV21600001 ER PT J AU CHAKOUMAKOS, BC FERNANDEZBACA, JA BOATNER, LA AF CHAKOUMAKOS, BC FERNANDEZBACA, JA BOATNER, LA TI REFINEMENT OF THE STRUCTURES OF THE LAYER SILICATES MCUSI4O10 (M = CA, SR, BA) BY RIETVELD ANALYSIS OF NEUTRON POWDER DIFFRACTION DATA SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article RP CHAKOUMAKOS, BC (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. RI Fernandez-Baca, Jaime/C-3984-2014; Chakoumakos, Bryan/A-5601-2016; Boatner, Lynn/I-6428-2013 OI Fernandez-Baca, Jaime/0000-0001-9080-5096; Chakoumakos, Bryan/0000-0002-7870-6543; Boatner, Lynn/0000-0002-0235-7594 NR 20 TC 23 Z9 23 U1 0 U2 7 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD MAR PY 1993 VL 103 IS 1 BP 105 EP 113 DI 10.1006/jssc.1993.1083 PG 9 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA KV216 UT WOS:A1993KV21600012 ER PT J AU SEVOV, SC CORBETT, JD AF SEVOV, SC CORBETT, JD TI SYNTHESIS, CHARACTERIZATION, AND BONDING OF INDIUM CLUSTER PHASES - NA15IN27.4, A NETWORK OF IN16 AND IN11 CLUSTERS - NA2IN WITH ISOLATED INDIUM TETRAHEDRA SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID BETA-NASN; RESISTIVITY C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP SEVOV, SC (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 21 TC 69 Z9 69 U1 1 U2 4 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD MAR PY 1993 VL 103 IS 1 BP 114 EP 130 DI 10.1006/jssc.1993.1084 PG 17 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA KV216 UT WOS:A1993KV21600013 ER PT J AU KRAMER, K KELLER, L FISCHER, P JUNG, B EDELSTEIN, NN GUDEL, HU MEYER, G AF KRAMER, K KELLER, L FISCHER, P JUNG, B EDELSTEIN, NN GUDEL, HU MEYER, G TI MAGNETIC AND CRYSTAL-STRUCTURE DETERMINATION OF K2UBR5 SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID NEUTRON-DIFFRACTION; PHASE-TRANSITIONS; CHLORIDES; FIELD; UCL3 C1 UNIV BERN,INST ANORGAN ANALYT & PHYS CHEM,CH-3000 BERN,SWITZERLAND. ETH ZURICH,NEUTRONENSTREUUNG LAB,CH-5232 VILLIGEN,SWITZERLAND. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP KRAMER, K (reprint author), UNIV HANNOVER,INST ANORGAN CHEM,CALLINSTR 9,W-3000 HANNOVER,GERMANY. RI Kramer, Karl/J-5021-2013 OI Kramer, Karl/0000-0001-5524-7703 NR 23 TC 9 Z9 9 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 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD MAR PY 1993 VL 103 IS 1 BP 152 EP 159 DI 10.1006/jssc.1993.1087 PG 8 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA KV216 UT WOS:A1993KV21600016 ER PT J AU SOLEM, JC AF SOLEM, JC TI INTERCEPTION OF COMETS AND ASTEROIDS ON COLLISION COURSE WITH EARTH SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB I delineate the utility, performance, and range of applicability of rocket interceptors designed to disrupt (deflect or pulverize) comets or asteroids on collision course with Earth. I discuss the relationship among several quantities of practical interest in the interception problem, the most important of which are 1) the mass in orbit or initial mass of the interceptor, which will usually dominate the cost of the system, and 2) the blowoff fraction, the fraction of the assailant object's mass expelled to impart transverse momentum, which also provides a measure of the probability that the object will fracture. I calculate optimum interception strategies for both kinetic-energy deflection and nuclear-explosive deflection, assuming a fairly general relationship between the energy deposited and the blowoff mass. In the nuclear-explosive case, I calculate the interceptor mass and cratering effect for detonations above and below the surface as well as directly on the surface of the assailant. Because different assailants could possess a wide range of densities and material properties, the principal value of this work is to show the relationships among the salient parameters. RP SOLEM, JC (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 19 TC 14 Z9 14 U1 1 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 1993 VL 30 IS 2 BP 222 EP 228 DI 10.2514/3.11531 PG 7 WC Engineering, Aerospace SC Engineering GA KW276 UT WOS:A1993KW27600011 ER PT J AU LARABELL, CA AF LARABELL, CA TI A NEW TECHNIQUE FOR ISOLATION AND VISUALIZATION OF THE XENOPUS EGG CORTEX REVEALS A COMPLEX CYTOSKELETON SO JOURNAL OF STRUCTURAL BIOLOGY LA English DT Article ID PROTEIN KINASE-C; SEA-URCHIN EGGS; CORTICAL GRANULE EXOCYTOSIS; ADRENAL CHROMAFFIN CELLS; AMPHIBIAN OOCYTE; LAEVIS; CALCIUM; ACTIN; ACTIVATION; SPECTRIN RP LARABELL, CA (reprint author), LAWRENCE BERKELEY LAB,W COAST FACIL INTERMEDIATE VOLTAGE ELECTRON MICROSCOPY,BERKELEY,CA 94720, USA. FU NCRR NIH HHS [RR05097] NR 29 TC 5 Z9 5 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 1047-8477 J9 J STRUCT BIOL JI J. Struct. Biol. PD MAR-APR PY 1993 VL 110 IS 2 BP 154 EP 159 DI 10.1006/jsbi.1993.1016 PG 6 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA LF551 UT WOS:A1993LF55100007 PM 8338718 ER PT J AU HODGSON, AT WOOLEY, JD DAISEY, JM AF HODGSON, AT WOOLEY, JD DAISEY, JM TI EMISSIONS OF VOLATILE ORGANIC-COMPOUNDS FROM NEW CARPETS MEASURED IN A LARGE-SCALE ENVIRONMENTAL CHAMBER SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID PULMONARY IRRITATION; SENSORY IRRITATION; EXPOSURE AB This study was undertaken to quantify the emissions of volatile organic compounds (VOCs) released by new carpets. Samples of four typical carpets, including two with styrene-butadiene rubber (SBR) latex adhesive and two with different backings, were collected from the finish lines at manufacturers' mills. Individual VOCs released from these samples were identified, and their concentrations, emission rates and mass emissions were measured under simulated indoor conditions in a 20 m3 environmental chamber over one week periods. Concentrations and emission rates of VOCs emitted by a new SBR carpet were also measured in a house. The carpets emitted a variety of VOCs. The two SBR carpets primarily emitted 4-phenylcyclohexene (4-PCH), the source of ''new carpet'' odor, and styrene. The concentrations and emission rates of 4-PCH were similar for the two carpets, while the styrene values varied significantly. The carpet with a polyvinyl chloride backing emitted formaldehyde, vinyl acetate, isooctane, 1,2-propanediol, and 2-ethyl-1-hexanol. Of these, vinyl acetate and propanediol had the highest concentrations an emission rates. The carpet with a polyurethane backing primarily emitted butylated hydroxytoluene. With the exception of formaldehyde, little is known about the health effects of these VOCs at low concentrations. RP HODGSON, AT (reprint author), LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,INDOOR ENVIRONM PROGRAM,MS 90-3058,BERKELEY,CA 94720, USA. NR 23 TC 55 Z9 56 U1 2 U2 6 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 MAR PY 1993 VL 43 IS 3 BP 316 EP 324 PG 9 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA KR802 UT WOS:A1993KR80200007 ER PT J AU FERNAU, ME AF FERNAU, ME TI AN ESTIMATE OF THE RECOVERABLE CHLOROFLUOROCARBONS AVAILABLE TO OFFSET FUTURE CARBON-DIOXIDE EMISSIONS SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID RELEASE; CCL3F AB The amount of sequestered chlorofluorocarbons (CFCs) in the United States that potentially is available for capture and destruction during the next several decades is estimated. This work is motivated by recent proposed legislation that would require utilities to offset new carbon dioxide (CO2) emissions in several possible ways, including capturing and destroying their equivalent in CFCs. Past and future domestic CFC-11 and CFC-12 production levels are determined; the annual sequestration amount is estimated; and an estimate of the recoverable amount of CFCs is made, expressed as carbon equivalents. The assumptions are such that an ''optimistic'' estimate is obtained, and the actual effectiveness of capture and recovery methods is not considered. Potentially recoverable CFCs peak in 1995-the first year in which recovery is assumed to occur-at around 130 million metric tons (Mt) carbon equivalent. The amount rapidly declines as production is affected by the Clean Air Act Amendments and other legislative restrictions on CFCs, reaching around 20 Mt in 2005 and then declining to about 2 Mt by 2015 and zero shortly thereafter. These amounts are sufficient in the late 1990s to help offset new CO2 emissions, but quickly become insignificant in the first several decades of the Twenty-First Century. RP FERNAU, ME (reprint author), ARGONNE NATL LAB,POLICY & ECON ANAL GRP,TECHNOL & ENVIRONM POLICY SECT,EID 900,ARGONNE,IL 60439, USA. NR 12 TC 0 Z9 0 U1 0 U2 0 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 MAR PY 1993 VL 43 IS 3 BP 336 EP 340 PG 5 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA KR802 UT WOS:A1993KR80200009 ER PT J AU BECHER, PF ALEXANDER, KB BLEIER, A WATERS, SB WARWICK, WH AF BECHER, PF ALEXANDER, KB BLEIER, A WATERS, SB WARWICK, WH TI INFLUENCE OF ZRO2 GRAIN-SIZE AND CONTENT ON THE TRANSFORMATION RESPONSE IN THE AL2O3-ZRO2 (12 MOL-PERCENT CEO2) SYSTEM SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID TETRAGONAL ZIRCONIA POLYCRYSTALS; FRACTURE-TOUGHNESS; MARTENSITIC TRANSFORMATIONS; PHASE-TRANSFORMATION; BRITTLE SOLIDS; STRESS-FIELD; CERAMICS; BEHAVIOR; THERMODYNAMICS; COMPOSITE AB Based on experimental and modeling studies, the rate of increase in the martensite start temperature M(s) for the tetragonal-to-monoclinic transformation with increase in zirconia grain size is found to rise with decrease in ZrO2 content in the zirconia-toughened alumina ZTA system. The observed grain size dependence of M(s) can be related to the thermal expansion mismatch tensile (internal) stresses which increase with decrease in zirconia content. The result is that finer zirconia grain sizes are required to retain the tetragonal phase as less zirconia is incorporated into the alumina, in agreement with the experimental observations. At the same time, both the predicted and observed applied stress required to induce the transformation are reduced with increase in the ZrO2 grain size. In addition, the transformation-toughening contribution at temperature T increases with increase in the M(s) temperature brought about by the increase in the ZrO2 grain size, when T > M(s). In alumina containing 20 vol% ZrO2 (12 mol% CeO2), a toughness of approximately 10 MPa. square-root m can be achieved for a ZrO2 grain size of approximately 2 mum (M(s) approximately 225 K). However, at a grain size of approximately 2 mum, the alumina-40 vol% ZrO2 (12 mol% CeO2) has a toughness of only 8.5 MPa. square-root m (M(s) approximately 150 K) but reaches 12.3 MPa. square-root m (M(s) approximately 260 K) at a grain size of approximately 3 mum. These findings show that composition (and matrix properties) play critical roles in determining the ZrO2 grain size to optimize the transformation toughening in ZrO2-toughened ceramics. RP BECHER, PF (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831, USA. NR 50 TC 73 Z9 75 U1 3 U2 14 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 MAR PY 1993 VL 76 IS 3 BP 657 EP 663 DI 10.1111/j.1151-2916.1993.tb03656.x PG 7 WC Materials Science, Ceramics SC Materials Science GA LE278 UT WOS:A1993LE27800012 ER PT J AU JENKINS, MG FERBER, MK LIN, CKJ AF JENKINS, MG FERBER, MK LIN, CKJ TI APPARENT ENHANCED FATIGUE RESISTANCE UNDER CYCLIC TENSILE LOADING FOR A HIPED SILICON-NITRIDE SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Note ID CERAMICS AB Cyclic tensile loading tests of a commercial HIPed silicon nitride at elevated temperatures have indicated apparent ''enhanced'' fatigue resistance compared to static tensile loading tests under similar test conditions. At 1150-degrees-C, stress rupture results plotted as maximum stress versus time to failure did not show significant differences in failure behavior between static, dynamic, or cyclic loading conditions, with all failures originating from preexisting defects (slow crack growth failures). At 1260-degrees-C, the stress rupture results showed pronounced differences between static, dynamic, and cyclic loading conditions. Failures at low static stresses (<175 MPa) originated from environmentally assisted (oxidation) and generalized creep damage, while failures at similar times but much greater (up to 2x) cyclic stresses originated from preexisting defects (slow crack growth failures). At 1370-degrees-C, stress rupture results did not show as pronounced differences between static, dynamic, and cyclic loading conditions, with most failures originating from environmentally assisted (oxidation) and generalized creep damage. C1 OAK RIDGE NATL LAB,HIGH TEMP MAT LAB,OAK RIDGE,TN 37831. OAK RIDGE INST SCI & EDUC,OAK RIDGE,TN 37831. RP JENKINS, MG (reprint author), UNIV WASHINGTON,DEPT MECH ENGN,SEATTLE,WA 98195, USA. NR 13 TC 18 Z9 18 U1 0 U2 0 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 MAR PY 1993 VL 76 IS 3 BP 788 EP 792 DI 10.1111/j.1151-2916.1993.tb03681.x PG 5 WC Materials Science, Ceramics SC Materials Science GA LE278 UT WOS:A1993LE27800037 ER PT J AU SMITHWICK, RW LYNCH, DW FRANKLIN, JC AF SMITHWICK, RW LYNCH, DW FRANKLIN, JC TI RELATIVE ION YIELDS MEASURED WITH A HIGH-RESOLUTION GLOW-DISCHARGE MASS-SPECTROMETER OPERATED WITH AN ARGON HYDROGEN MIXTURE SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article AB Quantitative elemental analysis by glow discharge mass spectrometry (GDMS) requires a calibration factor for each element. The calibration factors used in the present work are called relative ion yields (RIYs). The RIYs of each of 19 elements within samples of four National Institute of Standards and Technology steel reference materials (nos. 661-664) were measured using pure argon and an argon mixture containing 1.0% hydrogen by volume. The RIYs measured using pure argon correlated within a factor of approximately 2-3 to the RIYs calculated by a theoretical model. The RIYs measured for these 19 elements using the argon mixture containing 1.0% hydrogen correlated within a factor of approximately 1.3 to the calculated RIYs. These results may have significant analytical potential with respect to GDMS and may have application to other plasma techniques. RP SMITHWICK, RW (reprint author), MARTIN MARIETTA ENERGY SYST INC,OAK RIDGE Y12 PLANT,PLANT LAB,POB 2009,BLDG 9995,MS-8189,OAK RIDGE,TN 37831, USA. NR 11 TC 31 Z9 31 U1 0 U2 1 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 MAR PY 1993 VL 4 IS 3 BP 278 EP 285 DI 10.1016/1044-0305(93)85092-C PG 8 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA KQ876 UT WOS:A1993KQ87600012 PM 24234858 ER PT J AU STEINSMO, U ISAACS, HS AF STEINSMO, U ISAACS, HS TI DISSOLUTION AND REPASSIVATION KINETICS OF FE-CR ALLOYS IN PIT SOLUTIONS .1. EFFECT OF THE SURFACE SALT LAYER SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID LOCALIZED CORROSION; STAINLESS-STEELS; PASSIVATION; FILMS AB A study of the dissolution and repassivation of an Fe-17.4 a/o Cr alloy in a pencil-type artificial pit simulating one-dimensional diffusion, has been carried out in a chloride-containing bulk solution. The attainment of saturation of dissolution products within the artificial pit was characterized by the formation of a salt layer on the alloy surface. A transport model has been used to calculate the decrease in concentration at the metal interface for currents below that required to maintain the salt layer. The concentration at the metal interface was calculated from the balance of electrochemical dissolution and diffusion in the localized environment. The dissolution rate of the alloy showed a maximum at a particular concentration and, both this concentration, and the rate, increased with potential. Passivation took place below a critical concentration. The potential and critical current for passivation increased with potential. The dissolution kinetics were affected by a remnant film that was present on the metal surf ace after the salt layer had dissolved. Its effects during active anodic dissolution slowly disappeared with time. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RI Street, Steven/A-5398-2015 OI Street, Steven/0000-0002-8999-3701 NR 30 TC 42 Z9 42 U1 1 U2 13 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 MAR PY 1993 VL 140 IS 3 BP 643 EP 653 DI 10.1149/1.2056137 PG 11 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA KT622 UT WOS:A1993KT62200025 ER PT J AU ALLENDORF, MD AF ALLENDORF, MD TI EQUILIBRIUM PREDICTIONS OF THE ROLE OF ORGANOSILICON COMPOUNDS IN THE CHEMICAL VAPOR-DEPOSITION OF SILICON-CARBIDE SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID STICKING COEFFICIENTS; SURFACE; KINETICS; ADSORPTION; DIFFUSION; MECHANISM; SI AB Equilibrium calculations are reported for a range of conditions used to deposit silicon carbide (SiC) from Si-C-H mixtures such as those using SiH4, C2H4, and H-2 as reactants. Included are 37 molecules containing both silicon and carbon, allowing an assessment to be made of the importance of organosilicon species (and organosilicon radicals in particular) to the deposition process. The results indicate that Si2C and SiCH2 may contribute to epitaxial SiC deposition and that formation of these and other organosilicon species is favored by low H-2 concentrations. In addition, simulations of gas-phase equilibria expected under low-pressure, low-temperature conditions show that some organosilicon radicals that are kinetically favored are also thermodynamically favored. These include SiC2, SiCCH, and HSiCCH, which could result from the reaction of SiH2 with unsaturated reactants such as C2H2, The results suggest that combining an inert carrier gas with an excess of a surface-reactive hydrocarbon such as C2H2 could increase deposition rates without forming silicon-rich deposits. RP ALLENDORF, MD (reprint author), SANDIA NATL LABS,COMBUST RES FAC,LIVERMORE,CA 94551, USA. NR 34 TC 55 Z9 55 U1 0 U2 2 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 MAR PY 1993 VL 140 IS 3 BP 747 EP 753 DI 10.1149/1.2056152 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA KT622 UT WOS:A1993KT62200040 ER PT J AU PAEZ, TL HUNTER, N AF PAEZ, TL HUNTER, N TI NONLINEAR ASPECTS OF SHOCK RESPONSE IN ISOLATED ACCELEROMETERS SO JOURNAL OF THE IES LA English DT Article DE CHAOS; CHAOTIC VIBRATIONS; SHOCK; SHOCK MEASUREMENT; ACCELEROMETERS; ISOLATED ACCELEROMETERS AB Numerous investigators have studied the potential for chaotic vibrations of nonlinear systems. It has been shown for manY simple nonlinear systems that when they are excited severely enough, or with the appropriate parametric combinations, they will execute chaotic vibrations. The present investigation considers the potential for the occurrence of chaos in a Practical nonlinear system-the isolated accelerometer. A simple first-order model is proposed for the isolated accelerometer. It is shown that chaos can occur in the isolated accelerometer. A preliminary investigation into the bearing that this chaos potential has on the measurement of shock response is summarized. RP PAEZ, TL (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INST ENVIRONMENTAL SCI PI MT PROSPECT PA 940 E NORTHWEST HIGHWAY, MT PROSPECT, IL 60056 SN 1052-2883 J9 J IES JI J. IES PD MAR-APR PY 1993 VL 36 IS 2 BP 41 EP 47 PG 7 WC Engineering, Environmental; Environmental Sciences; Instruments & Instrumentation SC Engineering; Environmental Sciences & Ecology; Instruments & Instrumentation GA LC107 UT WOS:A1993LC10700008 ER PT J AU HENDRICKS, SP AF HENDRICKS, SP TI MICROBIAL ECOLOGY OF THE HYPORHEIC ZONE - A PERSPECTIVE INTEGRATING HYDROLOGY AND BIOLOGY SO JOURNAL OF THE NORTH AMERICAN BENTHOLOGICAL SOCIETY LA English DT Article DE HYDROLOGY; GROUNDWATER; HYPORHEIC ZONE; MICROBIAL ECOLOGY; BACTERIA; LOTIC ECOSYSTEMS AB A case study of hyporheic research in a northern Michigan river is presented to illustrate some potential effects of subsurface hydrology on microbial ecology. Hydrologic flow between a downwelling and an upwelling zone beneath a riffle-pool sequence promoted hyporheic-ground-water interaction and differentiated regions of increased bacterial activity, production, turnover time, and responsiveness to dissolved organic carbon enrichment. Large gaps in knowledge exist on the structure and function of fungal, bacterial, microalgal, protozoan, and micrometazoan assemblages within hyporheic zones. This study, combined with available literature on surface and groundwater microbial assemblages, generated several hypotheses for future research. Hydrological methods, when coupled with biochemical measurements, micro-techniques, and descriptions of hyporheic physicochemical and biological gradients, can potentially contribute to a greater understanding of the role of hyporheic microbial communities in the structure and function of lotic ecosystems. RP HENDRICKS, SP (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831, USA. NR 0 TC 91 Z9 97 U1 2 U2 21 PU NORTH AMER BENTHOLOGICAL SOC PI LAWRENCE PA 1041 NEW HAMSPHIRE STREET, LAWRENCE, KS 66044 SN 0887-3593 J9 J N AM BENTHOL SOC JI J. N. Am. Benthol. Soc. PD MAR PY 1993 VL 12 IS 1 BP 70 EP 78 DI 10.2307/1467687 PG 9 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA KR243 UT WOS:A1993KR24300009 ER PT J AU DUDNEY, NJ BATES, JB ROBERTSON, JD AF DUDNEY, NJ BATES, JB ROBERTSON, JD TI RADIOFREQUENCY MAGNETRON SPUTTERING OF PURE AND MIXED TARGETS OF LI4SIO4, LI3PO4, AND LI2O SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID THIN-FILMS; DISCHARGE CHARACTERISTICS; ELECTRICAL-CONDUCTIVITY; LITHIUM ORTHOSILICATE; IONIC-CONDUCTIVITY; GLASS SURFACES; DEPOSITION AB Pure and mixed targets of Li4SiO4, Li3PO4, and Li2O were sputtered in both argon and argon/oxygen process gases using a 1-in. diam radio-frequency planar magnetron source. The appearance of the sputter target, the self-bias voltage of the target, the film deposition rate, and the optical emission of the plasma were monitored during film growth. The films were analyzed by energy dispersive x-ray spectrometry, proton induced gamma emission, and atomic spectrometry. Films grown from targets of Li3PO4 were found to be near stoichiometric. In contrast, films grown from targets of, or containing, Li4SiO4 were lithium deficient due to the decomposition and segregation of Li2O away from the sputtered area on the surface of the target. A similar redistribution of material was observed for Li2O targets as well. Reproducible and homogeneous film compositions with stoichiometric lithium concentrations can best be achieved by codeposition with independently controlled sputter sources onto a rotating substrate. C1 UNIV KENTUCKY,DEPT CHEM,LEXINGTON,KY 40506. RP DUDNEY, NJ (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 37 TC 8 Z9 8 U1 1 U2 16 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 MAR-APR PY 1993 VL 11 IS 2 BP 377 EP 389 DI 10.1116/1.578739 PG 13 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA KT850 UT WOS:A1993KT85000014 ER PT J AU KLEPPER, CC EVANS, TE HAAS, G JACKSON, GL MAINGI, R AF KLEPPER, CC EVANS, TE HAAS, G JACKSON, GL MAINGI, R TI NEUTRAL PRESSURE STUDIES WITH A FAST IONIZATION GAUGE IN THE DIVERTOR REGION OF THE DIII-D TOKAMAK SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID PARTICLE EXHAUST; PUMP LIMITER AB An ionization gauge, specially designed to operate in the high magnetic fields of present-day tokamaks (1-6 T) and with electronics designed for fast time response and high noise rejection, was installed and operated in the new pumping plenum in the divertor region of DIII-D. This plenum, formed by a toroidally symmetric baffle, is used to compress neutrals to high pressures (> 1 mTorr) to allow for high particle removal rates when a pump is added inside the plenum. Pressures of 2-20 mTorr were measured with the fast gauge under the baffle, compared to less than 1 mTorr measured by a similar gauge also installed in the divertor but outside the baffle. A detailed description of the fast gauge, its operation, and its calibration is provided. C1 GEN ATOM,SAN DIEGO,CA 92186. MAX PLANCK INST PLASMA PHYS,W-8046 GARCHING,GERMANY. N CAROLINA STATE UNIV,RALEIGH,NC 27695. RP KLEPPER, CC (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 13 TC 19 Z9 20 U1 0 U2 5 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 MAR-APR PY 1993 VL 11 IS 2 BP 446 EP 450 DI 10.1116/1.578751 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA KT850 UT WOS:A1993KT85000026 ER PT J AU RUCKMAN, MW JIANG, LQ STRONGIN, M AF RUCKMAN, MW JIANG, LQ STRONGIN, M TI STUDY OF PALLADIUM MONOLAYERS AND MULTILAYERS ON TA(110) BETWEEN 300 AND 1500-K (VOL A10, PG 2551, 1992) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Correction, Addition RP RUCKMAN, MW (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 1 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 MAR-APR PY 1993 VL 11 IS 2 BP 466 EP 466 DI 10.1116/1.578757 PG 1 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA KT850 UT WOS:A1993KT85000032 ER PT J AU SHERWIN, ME CORLESS, R WENDT, JR AF SHERWIN, ME CORLESS, R WENDT, JR TI SUBMICRON, FOOTPRINT, AIR BRIDGES DEFINED BY ELECTRON-BEAM LITHOGRAPHY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Note RP SHERWIN, ME (reprint author), SANDIA NATL LABS,DEPT CPDS SEMICOND TECHNOL 1322,ALBUQUERQUE,NM 87185, USA. NR 0 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 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAR-APR PY 1993 VL 11 IS 2 BP 339 EP 340 DI 10.1116/1.586681 PG 2 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA KY050 UT WOS:A1993KY05000036 ER PT J AU TRINGIDES, MC SEYMOUR, P JACOBS, K BUSTA, HH POGEMILLER, JD AF TRINGIDES, MC SEYMOUR, P JACOBS, K BUSTA, HH POGEMILLER, JD TI SINGLE MICROMACHINED EMITTER CHARACTERISTICS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 5TH INTERNATIONAL VACUUM MICROELECTRONICS CONF CY JUL 13-17, 1992 CL VIENNA, AUSTRIA SP AMER VACUUM SOC, NATL SCI FDN, USN, OFF NAVAL RES, EUROPEAN OFF, USA, RES & DEV STANDARDIZAT GRP, SIEMENS DEUTSCHLAND, BUNDESMINIST WISSENSCH & FORSCH, OSTERREICH FORSCHUNGSGEMEINSCH, WIENER TOURISMUSVERBAND, SIEMENS OSTERRICH AB The emission from a single, lateral micromachined W protrusion on a silica substrate is examined to identify important factors controlling the emission of commercially interesting field emission arrays (FEAs). From the emission pattern of the single tip obtained on a phosphor screen and the I-V characteristics it was concluded that mini protrusions of a few hundred angstroms are responsible for the emission. Large fluctuations in the emission current are caused by absorption-desorption events from the background gas. Comparison of the I-V characteristics and the fluctuations of the single tip to gated FEAs (under the assumption that similar miniprotrusions are responsible for the emission in other geometries) suggests that only a fraction of the tips is emitting. C1 AMOCO TECHNOL CO,NAPERVILLE,IL 60566. RP TRINGIDES, MC (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,DEPT PHYS,AMES,IA 50011, USA. NR 8 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 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAR-APR PY 1993 VL 11 IS 2 BP 396 EP 399 DI 10.1116/1.586868 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA KY050 UT WOS:A1993KY05000047 ER PT J AU HIRSCH, VM DAPOLITO, GA GOLDSTEIN, S MCCLURE, H EMAU, P FULTZ, PN ISAHAKIA, M LENROOT, R MYERS, G JOHNSON, PR AF HIRSCH, VM DAPOLITO, GA GOLDSTEIN, S MCCLURE, H EMAU, P FULTZ, PN ISAHAKIA, M LENROOT, R MYERS, G JOHNSON, PR TI A DISTINCT AFRICAN LENTIVIRUS FROM SYKES MONKEYS SO JOURNAL OF VIROLOGY LA English DT Article ID SIMIAN IMMUNODEFICIENCY VIRUS; NF-KAPPA-B; GREEN MONKEYS; EXPERIMENTAL-INFECTION; HIGHLY DIVERGENT; CERCOCEBUS-ATYS; MACAQUE MONKEYS; SOOTY MANGABEY; TYPE-1; DIVERSITY AB Asymptomatic infection with simian immunodeficiency virus (SIV) has been demonstrated in African Sykes' monkeys (Cercopithecus mitis albogularis), and virus isolation confirmed infection with a novel SIV from Sykes' monkeys (SIVsyk). Macaques inoculated with SIVsyk became persistently infected but remained clinically healthy. We utilized polymerase chain reaction amplification to generate a full-length, infectious molecular clone of SIVsyk. The genome organization of SIVsyk is similar to that of the other primate lentiviruses, consisting of gag, pol, vif, vpr, tat, rev, env, and nef. A unique feature is the absence of the highly conserved NF-KB binding site in the long terminal repeat. SIVsyk is genetically equidistant from other primate lentiviruses. Thus, SIVsyk represents a new group that is distinct from the four previously recognized primate lentivirus groups: human immunodeficiency virus type 1 (HIV-1), SIV from sooty mangabeys (SIVsmm) and HIV-2, SIV from African green monkeys (SIVagm), and SIV from mandrills (SIVmnd). The genetic differences between SIVsyk and SIVagm, isolates derived from monkeys of the same genus, underscore the potential for other distinct SIVs which have yet to be isolated and characterized. C1 EMORY UNIV,YERKES REG PRIMATE RES CTR,ATLANTA,GA 30322. EMORY UNIV,DEPT PATHOBIOL,ATLANTA,GA 30322. UNIV ALABAMA,MED CTR,DEPT MICROBIOL,BIRMINGHAM,AL 35294. NATL MUSEUM KENYA,INST PRIMATE RES,NAIROBI,KENYA. LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87544. OHIO STATE UNIV,DEPT PEDIAT,COLUMBUS,OH 43210. RP HIRSCH, VM (reprint author), NIAID,INFECT DIS LAB,ROCKVILLE,MD 20852, USA. RI Johnson, Philip/A-6892-2009 FU NCRR NIH HHS [RR00165]; NIAID NIH HHS [N01-AI-772623] NR 47 TC 87 Z9 87 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0022-538X J9 J VIROL JI J. Virol. PD MAR PY 1993 VL 67 IS 3 BP 1517 EP 1528 PG 12 WC Virology SC Virology GA KM613 UT WOS:A1993KM61300045 PM 8382307 ER PT J AU DUFFIELD, W HEIKEN, G FOLEY, D MCEWEN, A AF DUFFIELD, W HEIKEN, G FOLEY, D MCEWEN, A TI OBLIQUE SYNOPTIC IMAGES, PRODUCED FROM DIGITAL DATA, DISPLAY STRONG EVIDENCE OF A NEW CALDERA IN SOUTHWESTERN GUATEMALA SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Article ID WESTERN AB The synoptic view of broad regions of the Earth's surface as displayed in Landsat and other satellite images has greatly aided in the recognition of calderas, ignimbrite plateaus and other geologic landforms. Remote-sensing images that include visual representation of depth are an even more powerful tool for geologic interpretation of landscapes, but their use has been largely restricted to the exploration of planets other than Earth. By combining Landsat images with digitized topography, we have generated regional oblique views that display compelling evidence for a previously undocumented late-Cenozoic caldera within the active volcanic zone of southwestern Guatemala. This ''new'' caldera, herein called Xela, is a depression about 30 km wide and 400-600 m deep, which includes the Quezaltenango basin. The caldera depression is breached only by a single river canyon. The caldera outline is broadly circular, but a locally scalloped form suggests the occurrence of multiple caldera-collapse events, or local slumping of steep caldera walls, or both. Within its northern part, Xela caldera contains a toreva block, about 500 m high and 2 km long, that may be incompletely foundered pre-caldera bedrock. Xela contains several post-caldera volcanoes, some of which are active. A Bouguer gravity low, tens of milligals in amplitude, is approximately co-located with the proposed caldera. The oblique images also display an extensive plateau that dips about 2-degrees away from the north margin of Xela caldera. We interpret this landform to be underlain by pyroclastic outflow from Xela and nearby Atitlan calderas. Field mapping by others has documented a voluminous rhyolitic pumiceous fallout deposit immediately east of Xela caldera. We speculate that Xela caldera was the source of this deposit. If so, the age of at least part of the caldera is between about 84 ka and 126 ka, the ages of deposits that stratigraphically bracket this fallout. Most of the floor of Xela caldera is covered with Los Chocoyos pyroclastics, 84-ka deposits erupted from Atitlan caldera. Oblique images produced from digital data are unique tools that can greatly facilitate initial geologic interpretation of morphologically young volcanic (and other) terrains where field access is limited, especially because conventional visual representations commonly lack depth perspective and may cover only part of the region of interest. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. PACIFIC LUTHERAN UNIV,DEPT EARTH SCI,TACOMA,WA 98447. RP DUFFIELD, W (reprint author), US GEOL SURVEY,2255 N GEMINI DR,FLAGSTAFF,AZ 86001, USA. NR 22 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0273 J9 J VOLCANOL GEOTH RES JI J. Volcanol. Geotherm. Res. PD MAR PY 1993 VL 55 IS 3-4 BP 217 EP 224 DI 10.1016/0377-0273(93)90038-S PG 8 WC Geosciences, Multidisciplinary SC Geology GA KU488 UT WOS:A1993KU48800003 ER PT J AU GAVRIKOV, SI PUTILIN, SN ZAKHAROV, ND AF GAVRIKOV, SI PUTILIN, SN ZAKHAROV, ND TI STRUCTURE AND DEFECTS OF LANTHANUM-PENTATANTALATE SO KRISTALLOGRAFIYA LA Russian DT Article ID RESOLUTION ELECTRON-MICROSCOPY C1 MOSCOW MV LOMONOSOV STATE UNIV,MOSCOW,RUSSIA. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP GAVRIKOV, SI (reprint author), RUSSIAN ACAD SCI,INST CRYSTALLOG,MOSCOW,RUSSIA. NR 7 TC 0 Z9 0 U1 1 U2 1 PU MEZHDUNARODNAYA KNIGA PI MOSCOW PA 39 DIMITROVA UL., 113095 MOSCOW, RUSSIA SN 0023-4761 J9 KRISTALLOGRAFIYA+ JI Kristallografiya PD MAR-APR PY 1993 VL 38 IS 2 BP 206 EP 216 PG 11 WC Crystallography SC Crystallography GA KW877 UT WOS:A1993KW87700024 ER PT J AU PEARSON, SM AF PEARSON, SM TI THE SPATIAL EXTENT AND RELATIVE INFLUENCE OF LANDSCAPE-LEVEL FACTORS ON WINTERING BIRD POPULATIONS SO LANDSCAPE ECOLOGY LA English DT Article DE SPECIES DIVERSITY; PATCHES; GRAIN; GEORGIA AB The influences of the landscape matrix (complex of habitats surrounding a study plot) and within-patch vegetation were studied in bird communities wintering in the piedmont of Georgia, USA. Variation at the landscape and within-patch levels was controlled to reduce the likelihood of confounding and spurious relationships. The landscape matrix within 500 m of each study plot was quantified from aerial photographs. Statistical models using landscape matrix and within-patch vegetation variables explained 73-84% of variation in bird abundance and diversity among sites with landscape matrix variables accounting for 30-90% of the variation. Variation in bird species richness and diversity was explained solely by landscape variables. Models for individual species such as Carolina Wrens (Thyrothorus ludovicianus) and Rufous-sided Towhees (Pipilo erythrophthalmus) had r2 > 0.80, with the landscape matrix variables accounting for the majority of this variation. However, other species like Northern Cardinals (Cardinalis cardinalis) and White-throated Sparrows (Zonotrichia albicollis) were most strongly influenced by within-plot vegetation. The landscape influence extended beyond habitats immediately adjacent to the study plots as indicated by significant variables describing variation in more distant habitat patches. These analyses illustrate a technique for comparing the strength of within-patch versus landscape influences and measuring the spatial extent of the landscape influence in fine-grained landscapes. RP PEARSON, SM (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,MS 6038,OAK RIDGE,TN 37831, USA. NR 0 TC 135 Z9 139 U1 1 U2 14 PU S P B ACADEMIC PUBLISHING BV PI LELYSTAD PA PLATINASTRAAT 33, 8211 AR LELYSTAD, NETHERLANDS SN 0921-2973 J9 LANDSCAPE ECOL JI Landsc. Ecol. PD MAR PY 1993 VL 8 IS 1 BP 3 EP 18 DI 10.1007/BF00129863 PG 16 WC Ecology; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA KW958 UT WOS:A1993KW95800001 ER PT J AU SHIH, MC PENG, JB HUANG, KG DUTTA, P AF SHIH, MC PENG, JB HUANG, KG DUTTA, P TI STRUCTURES OF FATTY-ACID MONOLAYERS TRANSFERRED TO GLASS SUBSTRATES FROM VARIOUS LANGMUIR MONOLAYER PHASES SO LANGMUIR LA English DT Article ID BLODGETT; SURFACE; WATER; FILM AB Langmuir-Blodgett monolayers of heneicosanoic acid were transferred to glass substrates from three phases of monolayers on water, whose structures are known to be (a) distorted-hexagonal with molecules tilted toward a near neighbor, (b) untilted distorted-hexagonal, and (c) untitled hexagonal. Specular X-ray reflectivity data show that all three transferred films have the same thickness, and X-ray diffraction data show that all three structures are untilted hexagonal. However, there are small differences in the in-plane diffraction peak positions and in the off-specular reflectivity that may be vestiges of the original structure. C1 NORTHWESTERN UNIV,DEPT PHYS & ASTRON,EVANSTON,IL 60208. UNIV QUEENSLAND,DEPT CHEM,BRISBANE,QLD 4072,AUSTRALIA. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. NR 22 TC 26 Z9 26 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR PY 1993 VL 9 IS 3 BP 776 EP 778 DI 10.1021/la00027a028 PG 3 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA KU388 UT WOS:A1993KU38800028 ER PT J AU BAIKERIKAR, KG HANSEN, RS AF BAIKERIKAR, KG HANSEN, RS TI ELECTROSORPTION OF 1-BUTANOL AT THE MERCURY ELECTROLYTIC SOLUTION INTERFACE IN THE PRESENCE OF SPECIFICALLY ADSORBED ANIONS - A TEST OF THE BASIC FRUMKIN MODEL SO LANGMUIR LA English DT Article AB The mercury-electrolytic solution interfacial tension gamma was measured at 25-degrees-C as a function of 1-butanol activity a(A) and polarization E measured against a saturated NaCl calomel electrode for 1-butanol reduced concentrations c/c0 from 0 to 0.5 at 50-mV intervals for 0.10 M electrolytes HClO4, KCl, KBr, and KI. For KCl, KBr, and KI the function ln(a(A)c0/c) Was found to vary linearly with c/c0 within experimental error; parameters for the linear functions are given. For HClO4, Values of ln(a(A)c0/c) were comparable to those for KCl for c/c0 > 0.2 but were irreproducible for lower values of c/c0. Plots of gamma(c/c0,E) with E referred to the electrocapillary maximum of the 0.10 M HClO4 and KCl base solutions (-0.477 V vs SSCE in both cases) for a given c/c0 for all four electrolytes were indistinguishable for E < -0.35 V, but as E became more positive than -0.35 V first the gamma(c/c0,E) curve for KI, then that for KBr, then that for KCl deviated negatively from that for HClO4. As c/c0 increased, the polarization required for divergence also increased. The basic Frumkin model for regular localized monolayer electrosorption was used to develop a master curve of pi/GAMMA(m)RT vs In Ba(A) With parameters GAMMA(m)RT, alpha, B0, C', and E(N) taken as the same for all electrolytes. These parameters and experimental values of gamma(0,E) permit determination of B(E)/B0, so that experimental points can be compared with the master curve. Results for E less-than-or-equal-to E' -0.1 with E' = 0.500, 0.300, and 0.000 V for KCl, KBr, and KI, fell quite close to the master curve for all values of a, with values of pi/GAMMA(m)RT deviating from it by more than 0.04 quite rare and no systematic pattern to deviations apparent. The basic Frumkin model, given its approximations and assumptions, is therefore remarkably satisfactory for data representation in this polarization range. At polarizations greater-than-or-equal-to E' -0.1, values of pi/GAMMA(m)RT lie increasingly higher than the master curve, indicating either additional contributions to pi/GAMMA(m)RT or underestimate of In B in the model. An empirical model based on specific anion adsorption within the complete organic monolayer was found capable of accounting for the deviations. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 23 TC 4 Z9 4 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR PY 1993 VL 9 IS 3 BP 851 EP 856 DI 10.1021/la00027a040 PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA KU388 UT WOS:A1993KU38800040 ER PT J AU SHAFFER, JS CHAKRABORTY, AK AF SHAFFER, JS CHAKRABORTY, AK TI DYNAMICS OF POLY(METHYL METHACRYLATE) CHAINS ADSORBED ON ALUMINUM SURFACES SO MACROMOLECULES LA English DT Article ID KINETIC ISING-MODEL; GLASS-TRANSITION; ISOMERIZATION DYNAMICS; MOLECULAR-DYNAMICS; POLYMER DYNAMICS; RELAXATION; LIQUIDS; STATES; ADSORPTION; INTERFACES AB We present a stochastic model for the dynamics of poly(methyl methacrylate) (PMMA) chains adsorbed on an aluminum surface. The model is able to investigate the relevant length scales and time scales of adsorbed polymers by employing a coarse-grained representation of the polymer chain (in terms of discrete adsorption states) and stochastic dynamics. The dynamics of the adsorbed polymers are governed by a master equation. The transition probabilities that enter the master equation have been derived by applying transition-state theory to the potential energy surface that describes the interactions of the PMMA segments with the aluminum surface. The potential energy surface has been obtained from previous quantum mechanical calculations for oligomers of PMMA near an aluminum surface. By incorporating the details of the segment-surface interactions, we are able to examine the effects of tacticity on the dynamics of adsorbed chains. We find qualitative similarities and quantitative differences between the dynamics of isotactic and syndiotactic PMMA adsorbed on aluminum. The dynamics of PMMA chains share several features with the dynamics of glass-forming liquids. Both systems exhibit nonexponential relaxation and non-Arrhenius temperature dependences of relaxation times. The physical sources of the glasslike dynamical behavior are a rugged energy surface and strong kinetic constraints. The microscopic basis for the kinetic constraints is discussed in detail. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. NR 54 TC 42 Z9 42 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD MAR 1 PY 1993 VL 26 IS 5 BP 1120 EP 1136 DI 10.1021/ma00057a036 PG 17 WC Polymer Science SC Polymer Science GA KP770 UT WOS:A1993KP77000036 ER PT J AU LIANG, GL NOID, DW SUMPTER, BG WUNDERLICH, B AF LIANG, GL NOID, DW SUMPTER, BG WUNDERLICH, B TI DYNAMICS OF A PARAFFIN CRYSTAL SO MAKROMOLEKULARE CHEMIE-THEORY AND SIMULATIONS LA English DT Article ID CONFORMATIONAL DISORDER; POLYETHYLENE; SIMULATION; ALKANES AB Recently it has become possible to make a series of simulations on a supercomputer of the molecular motion of a pentacontane (C50H102) crystal containing close to 1 0 000 atoms. Such a crystal is big enough to serve as a model of a macroscopic crystal. It can also serve as a model for polyethylene. The large volume of detailed information on the structure and motion permits a new level of understanding. Information on crystal appearance, pseudo-symmetric crystal structures, picosecond time-scale formation of conformational defects and the beginning of the melting process is presented. C1 OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 20 TC 14 Z9 14 U1 0 U2 2 PU HUTHIG & WEPF VERLAG PI BASEL PA AUF DEM WOLF 4 FX#001-41-61-317-94-11, CH-4052 BASEL, SWITZERLAND SN 1018-5054 J9 MAKROMOL CHEM-THEOR PD MAR PY 1993 VL 2 IS 2 BP 245 EP 255 PG 11 WC Polymer Science SC Polymer Science GA KT635 UT WOS:A1993KT63500006 ER PT J AU SIMPSON, WA MCCLUNG, RW AF SIMPSON, WA MCCLUNG, RW TI AN ULTRASONIC EVALUATION OF SILICON-CARBIDE WHISKER-REINFORCED CERAMIC COMPOSITES SO MATERIALS EVALUATION LA English DT Article DE ACOUSTIC MICROSCOPY; AUTOMOTIVE ENGINEERING; CERAMICS; COMPOSITE MATERIAL; LASER ACOUSTIC MICROSCOPY; NONDESTRUCTIVE INSPECTION; NUCLEAR INDUSTRY; SCANNING ACOUSTIC MICROSCOPY; SIGNAL PROCESSING; ULTRASONIC TESTING AB The excellent high-temperature properties of ceramics make them likely choices for use in advanced engine designs which permit higher combustion temperatures and thus higher thermodynamic efficiencies to be achieved. However, the relatively low fracture toughness, and hence small critical flaw size, of typical monolithic ceramics initially hindered their use as replacements for structural metals and led to the development of several techniques for toughening ceramics. One such technique is the dispersal of ceramic whiskers, whose presence inhibits crack propagation, in the ceramic matrix. Such composite structures show great promise for realizing the potential of ceramics but pose several unique problems for nondestructive testing. We describe the ultrasonic inspection of composite ceramics consisting of silicon carbide whiskers dispersed in both alumina and silicon nitride matrices. The detection of whisker clumping by high-frequency acoustic microscopy is described, and the rapid detection of this condition via the material transfer function, or attenuation versus frequency characteristic is presented. RP SIMPSON, WA (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,NONDESTRUCT TESTING GRP,POB 2008,4500S,MS 6158,OAK RIDGE,TN 37831, USA. NR 8 TC 1 Z9 1 U1 1 U2 1 PU AMER SOC NON-DESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD MAR PY 1993 VL 51 IS 3 BP 391 EP 395 PG 5 WC Materials Science, Characterization & Testing SC Materials Science GA KR562 UT WOS:A1993KR56200007 ER PT J AU DAW, MS FOILES, SM BASKES, MI AF DAW, MS FOILES, SM BASKES, MI TI THE EMBEDDED-ATOM METHOD - A REVIEW OF THEORY AND APPLICATIONS SO MATERIALS SCIENCE REPORTS LA English DT Review ID CORRECTED EFFECTIVE-MEDIUM; ORDER-DISORDER TRANSITIONS; ENERGY-ION-SCATTERING; X-RAY-DIFFRACTION; RAYLEIGH PHONON-DISPERSION; MONTE-CARLO SIMULATIONS; HE-SURFACE SCATTERING; 001 TWIST BOUNDARIES; MISSING-ROW MODEL; FCC 110 SURFACES AB The embedded-atom method (EAM) is a semi-empirical, many-atom potential for computing the total energy of a metallic system. It is especially useful for systems with large unit cells, and is appropriate for metals with empty or filled d bands. With the EAM, the materials community has investigated many problems of interest: point defects, melting, alloying, grain boundary structure and energy, dislocations, segregation, fracture, surface structure, and epitaxial growth. In general, most of the EAM calculations have been carried out in close connection with experimental work. We review here the history, development, and application of the EAM. C1 SANDIA NATL LABS, MAT & PROC RES DEPT, LIVERMORE, CA 94551 USA. RP DAW, MS (reprint author), SANDIA NATL LABS, DEPT THEORY, LIVERMORE, CA 94551 USA. OI Foiles, Stephen/0000-0002-1907-454X NR 161 TC 857 Z9 874 U1 16 U2 205 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-2307 J9 MATER SCI REP PD MAR PY 1993 VL 9 IS 7-8 BP 251 EP 310 DI 10.1016/0920-2307(93)90001-U PG 60 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA LB248 UT WOS:A1993LB24800001 ER PT J AU PERELSON, AS KIRSCHNER, DE DEBOER, R AF PERELSON, AS KIRSCHNER, DE DEBOER, R TI DYNAMICS OF HIV-INFECTION OF CD4+ T-CELLS SO MATHEMATICAL BIOSCIENCES LA English DT Article ID HUMAN-IMMUNODEFICIENCY-VIRUS; IMMUNE-SYSTEM RETROVIRUS; HTLV-III/LAV INFECTION; PERIPHERAL-BLOOD; MATHEMATICAL-MODEL; LYMPHOCYTE COUNTS; B-CELL; PATHOGENESIS; INDIVIDUALS; AIDS AB We examine a model for the interaction of HIV with CD4+ T cells that considers four populations: uninfected T cells, latently infected T cells, actively infected T cells, and free virus. Using this model we show that many of the puzzling quantitative features of HIV infection can be explained simply. We also consider effects of AZT on viral growth and T-cell population dynamics. The model exhibits two steady states, an uninfected state in which no virus is present and an endemically infected state, in which virus and infected T cells are present. We show that if N, the number of infectious virions produced per actively infected T cell, is less a critical value, N(crit), then the uninfected state is the only steady state in the nonnegative orthant, and this state is stable. For N > N(crit), the uninfected state is unstable, and the endemically infected state can be either stable, or unstable and surrounded by a stable limit cycle. Using numerical bifurcation techniques we map out the parameter regimes of these various behaviors. Oscillatory behavior seems to lie outside the region of biologically realistic parameter values. When the endemically infected state is stable, it is characterized by a reduced number of T cells compared with the uninfected state. Thus T-cell depletion occurs through the establishment of a new steady state. The dynamics of the establishment of this new steady state are examined both numerically and via the quasi-steady-state approximation. We develop approximations for the dynamics at early times in which the free virus rapidly binds to T cells, during an intermediate time scale in which the virus grows exponentially, and a third time scale on which viral growth slows and the endemically infected steady state is approached. Using the quasi-steady-state approximation the model can be simplified to two ordinary differential equations the summarize much of the dynamical behavior. We compute the level of T cells in the endemically infected state and show how that level varies with the parameters in the model. The model predicts that different viral strains, characterized by generating differing numbers of infective virions within infected T cells, can cause different amounts of T-cell depletion and generate depletion at different rates. Two versions of the model are studied. In one the source of T cells from precursors is constant, whereas in the other the source of T cells decreases with viral load, mimicking the infection and killing of T-cell precursors. The latter gives more realistic predictions than the model with a constant source. C1 VANDERBILT UNIV,DEPT MATH,NASHVILLE,TN 37240. RP PERELSON, AS (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87544, USA. RI De Boer, Rob/B-6050-2011 OI De Boer, Rob/0000-0002-2130-691X FU NCRR NIH HHS [RR06555]; NIAID NIH HHS [AI28433] NR 65 TC 403 Z9 417 U1 11 U2 35 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0025-5564 J9 MATH BIOSCI JI Math. Biosci. PD MAR PY 1993 VL 114 IS 1 BP 81 EP 125 DI 10.1016/0025-5564(93)90043-A PG 45 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA KM041 UT WOS:A1993KM04100004 PM 8096155 ER PT J AU MAUSNER, LF SRIVASTAVA, SC AF MAUSNER, LF SRIVASTAVA, SC TI SELECTION OF RADIONUCLIDES FOR RADIOIMMUNOTHERAPY SO MEDICAL PHYSICS LA English DT Article ID LABELING MONOCLONAL-ANTIBODIES; CANCER-THERAPY; MAMMALIAN-CELLS; EMITTING RADIONUCLIDES; INVIVO STABILITY; TUMOR-THERAPY; ASTATINE-211; RADIOTHERAPY; MODEL; AGENT RP MAUSNER, LF (reprint author), BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973, USA. NR 83 TC 93 Z9 93 U1 0 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 MAR-APR PY 1993 VL 20 IS 2 BP 503 EP 509 DI 10.1118/1.597045 PN 2 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA KZ773 UT WOS:A1993KZ77300004 PM 8492758 ER PT J AU WATSON, EE STABIN, MG SIEGEL, JA AF WATSON, EE STABIN, MG SIEGEL, JA TI MIRD FORMULATION SO MEDICAL PHYSICS LA English DT Article ID INTERNAL DOSIMETRY; RADIONUCLIDES; BLOOD C1 COOPER HOSP UNIV MED CTR,CAMDEN,NJ 08103. RP WATSON, EE (reprint author), OAK RIDGE INST SCI & EDUC,OAK RIDGE,TN 37831, USA. NR 30 TC 27 Z9 27 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 MAR-APR PY 1993 VL 20 IS 2 BP 511 EP 514 DI 10.1118/1.597046 PN 2 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA KZ773 UT WOS:A1993KZ77300005 PM 8492759 ER PT J AU HUMM, JL ROESKE, JC FISHER, DR CHEN, GTY AF HUMM, JL ROESKE, JC FISHER, DR CHEN, GTY TI MICRODOSIMETRIC CONCEPTS IN RADIOIMMUNOTHERAPY SO MEDICAL PHYSICS LA English DT Article DE MICRODOSIMETRY; RADIOLABELED ANTIBODIES; ENERGY DEPOSITION; ALPHA-EMITTERS; BETA-EMITTERS ID EMITTING RADIONUCLIDES; MONOCLONAL-ANTIBODY; DOSIMETRY; TISSUE; TUMOR AB In microdosimetry particular emphasis is placed on the stochastic fluctuation of dose in small target volumes such as individual cell nuclei or chromatin fiber, and their relevance to radiobiologic toxicity. Thus microdosimetry is intimately associated with models of radiation action. There are three principal areas where microdosimetry has been applied: (1) radiation protection, (2) high LET radiotherapy, e.g., neutron therapy, and (3) incorporated radionuclides, and in this latter category the importance of microdosimetry to the radiobiology of radiolabeled antibodies is becoming increasingly recognized. The objective of microsdosimetry is the complete characterization of energy deposition within all target volumes throughout the tissue of interest. The importance and relevance of this pursuit will depend upon the properties of the radionuclide emissions and the spatial distribution of the radionuclide relative to the target volumes. If the distribution of internal emitters within both malignant and normal tissue is uniform, the application of microdosimetry to radioimmunotherapy (RIT) is limited to alpha-emitters and Auger emitters. Under such circumstances the traditional MIRD formalism for the evaluation of tumor and tissue doses from the commonly used beta-emitters is entirely adequate. This, however, is rarely the case. When the distribution of radiolabeled antibody is nonuniform, techniques of dose averaging over volumes greater in size than the individual target volumes can become inadequate predictors of the biological effect. The concepts, methods, and realm of applicability of microdosimetry within the field of radioimmunotherapy are emphasized in this paper. C1 UNIV CHICAGO, MED CTR, CHICAGO, IL 60637 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. RP HUMM, JL (reprint author), HARVARD UNIV, SCH MED, JOINT CTR RADIAT THERAPY, 50 BINNEY ST, BOSTON, MA 02115 USA. FU NCI NIH HHS [IR03 CA50886] NR 34 TC 57 Z9 59 U1 2 U2 6 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 MAR-APR PY 1993 VL 20 IS 2 BP 535 EP 541 DI 10.1118/1.597049 PN 2 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA KZ773 UT WOS:A1993KZ77300008 PM 8492762 ER PT J AU MEI, Z MORRIS, JW AF MEI, Z MORRIS, JW TI THE GROWTH OF SMALL FATIGUE CRACKS IN A286 STEEL SO METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID PROPAGATION; BEHAVIOR; CLOSURE; INITIATION; THRESHOLD; STRESS AB Fatigue crack propagation in high-strength A286 steel was studied by comparing crack growth rates determined from: (1) conventional long-crack propagation tests, (2) closure-free long-crack tests at constant K(max), and (3) small-crack propagation tests. Small-crack growth rates were measured by following the growth of surface cracks in samples cycled from near-zero stress to 0.5 or 0.8sigma(y). While most of the surface cracks became dormant shortly after nucleation, some grew into long cracks, and some of these propagated at cyclic stress intensities below the long-crack threshold, DELTAK(th) (or DELTAK(th)eff, the threshold cyclic stress intensity after crack closure effects have been removed). Surface cracks grew more rapidly than long cracks at the same DELTAK or DELTAK(eff). The small-crack effect disappeared when the crack-tip plastic zone size became greater than the grain size. The results show that the absence of crack closure is only one of several factors that influence short-crack growth in A286 steel. Both peak stress and microstructural effects are important. Microstructural effects are apparently responsible for subthreshold crack growth; the cracks that grow at DELTAK < DELTAK(th)eff form and grow in statistically weak regions of the microstructure. C1 LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. RP MEI, Z (reprint author), UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720, USA. NR 30 TC 9 Z9 9 U1 1 U2 5 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0360-2133 J9 METALL TRANS A PD MAR PY 1993 VL 24 IS 3 BP 689 EP 700 DI 10.1007/BF02656637 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA KP614 UT WOS:A1993KP61400017 ER PT J AU RAO, KTV SIU, SC RITCHIE, RO AF RAO, KTV SIU, SC RITCHIE, RO TI FAILURE MECHANISMS IN SIC-FIBER REINFORCED-6061 ALUMINUM-ALLOY COMPOSITES UNDER MONOTONIC AND CYCLIC LOADING SO METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID FATIGUE CRACK-GROWTH; MATRIX COMPOSITES; FRACTURE; TOUGHNESS; BEHAVIOR; SIZE AB Micromechanisms influencing crack propagation in a unidirectional SiC-fiber (SCS-8) continuously reinforced Al-Mg-Si 6061 alloy metal-matrix composite (SiC(f)/Al-6061) during monotonic and cyclic loading are examined at room temperature, both for the longitudinal (0 deg or L-T) and transverse (90 deg or T-L) orientations. It is found that the composite is insensitive to the presence of notches in the L-T orientation under pure tension loading due to the weak fiber/matrix interface; notched failure strengths are approximately 1500 MPa compared to 124 MPa for unreinforced 6061. However, behavior is strongly dependent on loading configuration, specimen geometry, and orientation. Specifically, properties in SiC(f)/Al in the T-L orientation are inferior to unreinforced 6061, although the composite does exhibit increasing crack-growth resistance with crack extension (resistance-curve behavior) under monotonic loading; peak toughnesses of approximately 16 MPa square-root m are achieved due to crack bridging by the continuous metal phase between fibers and residual plastic deformation in the crack wake. In contrast, such bridging is minimal under cyclic loading, as the ductile phase fails subcritically by fatigue such that the transverse fatigue crack-growth resistance is superior in the unreinforced alloy, particularly at high stress-intensity levels. Conversely, fatigue cracks are bridged by unbroken SiC fibers in the L-T orientation and exhibit marked crack deflection and branching; the fatigue crack-growth resistance in this orientation is clearly superior in the composite. C1 LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. RP RAO, KTV (reprint author), UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720, USA. RI Ritchie, Robert/A-8066-2008 OI Ritchie, Robert/0000-0002-0501-6998 NR 37 TC 23 Z9 23 U1 0 U2 3 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0360-2133 J9 METALL TRANS A PD MAR PY 1993 VL 24 IS 3 BP 721 EP 734 DI 10.1007/BF02656640 PG 14 WC Materials Science, Multidisciplinary SC Materials Science GA KP614 UT WOS:A1993KP61400020 ER PT J AU CAREY, PG WORATSCHEK, BJ BACHMANN, F AF CAREY, PG WORATSCHEK, BJ BACHMANN, F TI PROGRESS TOWARD EXCIMER-LASER METAL PLANARIZATION AND VIA HOLE FILLING USING INSITU MONITORING SO MICROELECTRONIC ENGINEERING LA English DT Article DE PLANARIZATION; LASER PROCESSING; METALLIZATION; INSITU MONITORING AB Future high-density interconnect and multilevel metalization schemes will require planarized dielectric and metalization layers in order to satisfy stringent photolithographic and step coverage requirements. Excimer lasers represent one possible solution for metal planarization. Pulsed excimer lasers irradiate the metal layer with very short (pulse full width at half maximum FWHM almost-equal-to 25-40 ns) highly energetic (up to 10 J cm-2) homogenized beams to melt an absorbing metal overlayer. While molten, the surface is driven flat due to the surface tension and low viscosity of metals. In this work we review our excimer laser planarization work, introduce the concept of in-situ monitoring to design a high-aspect-ratio contact hole filling planarization process, and summarize prospects for future work. RP CAREY, PG (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 5503,L-271,LIVERMORE,CA 94551, USA. NR 0 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9317 J9 MICROELECTRON ENG JI Microelectron. Eng. PD MAR PY 1993 VL 20 IS 1-2 BP 89 EP 106 DI 10.1016/0167-9317(93)90209-N PG 18 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Optics; Physics, Applied SC Engineering; Science & Technology - Other Topics; Optics; Physics GA LA913 UT WOS:A1993LA91300008 ER PT J AU WEINER, KH CAREY, PG MCCARTHY, AM SIGMON, TW AF WEINER, KH CAREY, PG MCCARTHY, AM SIGMON, TW TI AN EXCIMER-LASER-BASED NANOSECOND THERMAL-DIFFUSION TECHNIQUE FOR ULTRA-SHALLOW PN JUNCTION FABRICATION SO MICROELECTRONIC ENGINEERING LA English DT Article DE EXCIMER LASER DOPING; SHALLOW JUNCTION; NANOSECOND THERMAL PROCESSING AB In this paper we review the development of nanosecond thermal diffusion (NTD), a new doping technology which utilizes excimer-laser-induced heating to incorporate and diffuse impurities in silicon wafers. With thermal anneals less than 200 ns in duration, the new laser-based method permits simple, low-temperature fabrication of the ultrashallow p-n junctions necessary for deep-submicrometer MOS and bipolar transistors. In a multifaceted research effort, we are building advanced equipment, developing accurate simulation tools, and designing effective process flows to demonstrate the viability of the NTD technique for manufacturing applications. To date we have fabricated p+-n and n+-p diodes with 300 angstrom junction depth, submicrometer PMOS transistors, and narrow-base regions in bipolar devices. Included in our results are: ultra-shallow diodes with ideality factors of 1.01-1.10 over seven decades of current, reverse leakage currents less than 10 nA/cm2 at 5 V reverse bias, and breakdown voltages in excess of 100 V, MOS devices that demonstrate excellent short channel behavior and no threshold voltage shift at submicrometer gate lengths, and bipolar transistors that incorporate base widths which range from 700 angstrom to 1200 angstrom and exhibit current gains between 50 and 200. C1 OREGON GRAD INST,BEAVERTON,OR 97006. RP WEINER, KH (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 5503,L-271,LIVERMORE,CA 94551, USA. NR 0 TC 19 Z9 19 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9317 J9 MICROELECTRON ENG JI Microelectron. Eng. PD MAR PY 1993 VL 20 IS 1-2 BP 107 EP 130 DI 10.1016/0167-9317(93)90210-V PG 24 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Optics; Physics, Applied SC Engineering; Science & Technology - Other Topics; Optics; Physics GA LA913 UT WOS:A1993LA91300009 ER PT J AU FLORES, BM BATZER, MA STEIN, MA PETERSEN, C DIEDRICH, DL TORIAN, BE AF FLORES, BM BATZER, MA STEIN, MA PETERSEN, C DIEDRICH, DL TORIAN, BE TI STRUCTURAL-ANALYSIS AND DEMONSTRATION OF THE 29-KDA ANTIGEN OF PATHOGENIC ENTAMOEBA-HISTOLYTICA AS THE MAJOR ACCESSIBLE FREE THIOL-CONTAINING SURFACE PROTEIN SO MOLECULAR MICROBIOLOGY LA English DT Article ID POLYACRYLAMIDE GELS; DISULFIDE BONDS; STABILITY; GLUTATHIONE; CYSTEINE; SEQUENCE; CELLS; ACID AB The 29 kDa protein of pathogenic Entamoeba histolytica is a cysteine-rich surface antigen which we recently characterized by cDNA sequencing and by using monoclonal antibodies which differentiated between pathogenic and non-pathogenic clinical isolates. To determine the structure and biochemical attributes of this protein, a repertoire of immunological techniques using monoclonal antibodies, and radiolabelling were employed. We demonstrated that the 29 kDa protein forms a 60 kDa dimer and a high-molecular-mass oligomer(s) on the surface of the organism through disulphide bonds, and is the major accessible free thiol-containing surface protein of E histolytica. The deduced amino acid sequence encoding the 29 kDa protein was found to share a common amino acid domain with sequences reported for Helicobacter pylori, Salmonella typhimurium, MER5 gene expressed in murine erythroleukemia cells, Clostridium pasteurianum, and a Bacillus spp. C1 IDAHO STATE UNIV,COLL PHARM,DEPT PHARMACEUT SCI,POCATELLO,ID 83209. LAWRENCE LIVERMORE NATL LAB,CTR HUMAN GENOME,DIV BIOMED SCI,LIVERMORE,CA 94551. SAN FRANCISCO GEN HOSP,PARASITOL LAB,SAN FRANCISCO,CA 94110. UNIV CALIF SAN FRANCISCO,SAN FRANCISCO,CA 94110. FU NIAID NIH HHS [AI28188]; NIGMS NIH HHS [GM 34838] NR 33 TC 29 Z9 30 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0950-382X J9 MOL MICROBIOL JI Mol. Microbiol. PD MAR PY 1993 VL 7 IS 5 BP 755 EP 763 DI 10.1111/j.1365-2958.1993.tb01166.x PG 9 WC Biochemistry & Molecular Biology; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA KQ909 UT WOS:A1993KQ90900013 PM 7682280 ER PT J AU STIGTER, J SCHNEIDER, M DEBRUIJN, FJ AF STIGTER, J SCHNEIDER, M DEBRUIJN, FJ TI AZORHIZOBIUM-CAULINODANS NITROGEN-FIXATION (NIF FIX) GENE-REGULATION - MUTAGENESIS OF THE NIFA-24/-12 PROMOTER ELEMENT, CHARACTERIZATION OF A NTRA(RPON) GENE, AND DERIVATION OF A MODEL SO MOLECULAR PLANT-MICROBE INTERACTIONS LA English DT Article DE NITROGEN REGULATION; NTRA; RPON; PROMOTER ANALYSIS ID TRANSPOSON TN5 MUTAGENESIS; KLEBSIELLA-PNEUMONIAE-NIFL; SITE-DIRECTED MUTAGENESIS; RHIZOBIUM-MELILOTI NTRA; GRAM-NEGATIVE BACTERIA; SIGMA-FACTOR GENE; TURN-HELIX MOTIF; ESCHERICHIA-COLI; RHODOBACTER-CAPSULATUS; NUCLEOTIDE-SEQUENCE AB Using site-directed mutagenesis, mutations were introduced in the -24/-12 promoter element of the Azorhizobium caulnodans nifA gene, and chimeric nifA-lacZ reporter gene fusions were constructed. Single base-pair mutations in the conserved -25 or -13 G residues were found to reduce or abolish nifA promoter activity, respectively, demonstrating that the -24/-12 promoter element is important for nifA gene expression and suggesting the involvement of a sigma54 (NtrA/RpoN)-type transcription factor in nifA gene regulation. A 2-bp mutation at positions -25 and -16 was found to create a relatively nitrogen-control-independent, highly expressed nifA promoter. Using a heterologous ntrA(rpoN) gene probe, an A. caulinodans ntrA(rpoN)-like gene was cloned and the DNA sequence of this gene and flanking regions was determined. The presence of three open reading frames (ORF1-3) was demonstrated. ORF2 was found to contain regions sharing a high degree of homology with all characterized bacterial ntrA(rpoN) genes. ORF1 was found to share homology with ORFs found upstream of other bacterial ntrA(rpoN) genes, which have been postulated to encode members of a superfamily of ATP-binding proteins. Transposon Tn5 insertion mutations were introduced into the cloned ntrA(rpoN) gene, and chromosomal ntrA(rpoN)=Tn5 A. caulinodans mutants were created. The resulting mutants were found to be unable to fix nitrogen in the free-living state (Nif- in culture) or in stem or root nodules induced on Sesbania rostrata (Fix- in planta), and to be unable to grow aerobically in the presence of nitrate as sole nitrogen source (Ntr-). A nifH-lacZ gene fusion was found to be silent in ntrA (rpoN)=Tn5 mutant strains, but a nifA - lacZ gene fusion was found to be expressed at a wild-type level, suggesting that the ntrA(rpoN) gene identified here controls the expression of some of the A. caulinodans nif genes, but not the central nif regulatory gene nifA. Based on these results, a new model for the regulation of nif/fix gene expression in A. caulinodans is proposed. C1 MICHIGAN STATE UNIV,DOE,PLANT RES LAB,E LANSING,MI 48824. MICHIGAN STATE UNIV,DEPT MICROBIOL,E LANSING,MI 48824. MICHIGAN STATE UNIV,NSF,CTR MICROBIAL ECOL,E LANSING,MI 48824. NR 89 TC 29 Z9 32 U1 2 U2 2 PU AMER PHYTOPATHOLOGICAL SOC PI ST PAUL PA 3340 PILOT KNOB ROAD, ST PAUL, MN 55121 SN 0894-0282 J9 MOL PLANT MICROBE IN JI Mol. Plant-Microbe Interact. PD MAR-APR PY 1993 VL 6 IS 2 BP 238 EP 252 DI 10.1094/MPMI-6-238 PG 15 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Plant Sciences SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Plant Sciences GA MD257 UT WOS:A1993MD25700010 PM 8471796 ER PT J AU YOST, FG AF YOST, FG TI FEDERAL-REGULATIONS CREATE NEW CHALLENGES IN MATERIALS SCIENCE SO MRS BULLETIN LA English DT Article ID OZONE RP YOST, FG (reprint author), SANDIA NATL LABS,CTR SOLDER SCI & TECHNOL,ALBUQUERQUE,NM 87185, USA. NR 6 TC 0 Z9 0 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 MAR PY 1993 VL 18 IS 3 BP 5 EP 6 PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA KT464 UT WOS:A1993KT46400001 ER PT J AU TARNOW, E AF TARNOW, E TI HELP FOR THE UNEMPLOYED SO MRS BULLETIN LA English DT Letter RP TARNOW, E (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544, USA. NR 0 TC 0 Z9 0 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 MAR PY 1993 VL 18 IS 3 BP 11 EP 11 PG 1 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA KT464 UT WOS:A1993KT46400003 ER PT J AU SCHWARTZ, JL COWEN, JM MOAN, E SEDITA, BA STEPHENS, J VAUGHAN, ATM AF SCHWARTZ, JL COWEN, JM MOAN, E SEDITA, BA STEPHENS, J VAUGHAN, ATM TI METAPHASE CHROMOSOME AND NUCLEOID DIFFERENCES BETWEEN CHO-K1 AND ITS RADIOSENSITIVE DERIVATIVE XRS-5 SO MUTAGENESIS LA English DT Article ID RAY-SENSITIVE MUTANTS; DOUBLE-STRAND BREAKS; DNA-DAMAGING AGENTS; CELL-LINES; IONIZING-RADIATION; REPAIR AB The Chinese hamster ovary (CHO) cell line xrs-5 is a radiation-sensitive mutant isolated from CHO-K1 cells. The radiation sensitivity is associated with a defect in DNA double-strand break rejoining. Chromatin structure also appears altered in xrs-5 cells compared with the parental CHO-K1 cells. Metaphase chromosomes from xrs-5 are more condensed in appearance than CHO-K1 chromosomes. The overcondensed look is not the result of colcemid sensitivity. Electron microscopy studies suggest that xrs-5 metaphase chromosomes have larger loops of chromatin extending out from the chromosome core. There are also differences between CHO-K1 and xrs-5 cells in the size and fluorescence pattern of ethidium bromide-stained nucleoid preparations. These results suggest that there is a fundamental difference between CHO-K1 and xrs-5 in either the organization of the supercoiled loops of DNA attached to the nuclear matrix or in the nature of the proteins that attach the DNA to the matrix. These alterations in chromosome structure may underlie, in part, the radiation sensitivity of xrs-5 cells. C1 UNIV CHICAGO,MED CTR,DEPT RADIAT & CELLULAR ONCOL,CHICAGO,IL 60637. UNIV CHICAGO,MED CTR,DEPT SURG PATHOL,CHICAGO,IL 60637. HINES VA HOSP,LOYOLA HINES DEPT RADIOTHERAPY,HINES,IL 60141. RP SCHWARTZ, JL (reprint author), ARGONNE NATL LAB,DIV BIOL & MED RES,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 21 TC 16 Z9 16 U1 2 U2 3 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0267-8357 J9 MUTAGENESIS JI Mutagenesis PD MAR PY 1993 VL 8 IS 2 BP 105 EP 108 DI 10.1093/mutage/8.2.105 PG 4 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA KT338 UT WOS:A1993KT33800003 PM 8464379 ER PT J AU GOLD, LS SLONE, TH STERN, BR BERNSTEIN, L AF GOLD, LS SLONE, TH STERN, BR BERNSTEIN, L TI COMPARISON OF TARGET ORGANS OF CARCINOGENICITY FOR MUTAGENIC AND NONMUTAGENIC CHEMICALS SO MUTATION RESEARCH LA English DT Article DE TARGET ORGAN, MUTAGENICITY; MULTIPLE-SITE CARCINOGEN; ANIMAL CANCER TEST; CARCINOGENIC POTENCY DATABASE; SPECIES DIFFERENCES ID NATIONAL-TOXICOLOGY-PROGRAM; SALMONELLA MUTAGENICITY; POTENCY DATABASE; ANIMAL BIOASSAYS; CHRONOLOGICAL SUPPLEMENT; RODENT CARCINOGENS; 42 CHEMICALS; B6C3F1 MICE; RATS; TESTS AB A comparison of target organs for mutagens and non-mutagens is presented for 351 rodent carcinogens in the Carcinogenic Potency Database (CPDB) with mutagenicity evaluations in Salmonella. Results are consistent with the hypotheses that in high-dose rodent tests mitogenesis is important in the carcinogenic response for mutagens and non-mutagens alike, and that mutagens have a multiplicative interaction for carcinogenicity because they can both damage DNA directly and cause cell division at high doses. These hypotheses would lead one to expect several results that are found in the analysis: First, a high proportion of both mutagens and non-mutagens induce tumors in rodent bioassays at the MTD. Second, mutagens compared to non-mutagens are: (a) more likely to be carcinogenic; (b) more likely to induce tumors at multiple target sites; and (c) more likely to be carcinogenic in two species. Among carcinogens that induce tumors at multiple sites in both rats and mice, 81% are mutagens; in comparison, among carcinogens that are positive at only a single target site in one species and are negative in the other, 42% are mutagens. Since tissue distribution and pharmacokinetics would not be expected to differ systematically between mutagens and non-mutagens, one would not expect systematic differences in the particular organs in which tumors are induced. Results do not support the idea that mutagens and non-mutagens induce tumors in different target organs. Both mutagens and non-mutagens induce tumors in a wide variety of sites, and most organs are target sites for both. Moreover, the same sites tend to be the most common sites for both: 79% or more of both mutagenic and non-mutagenic carcinogens are positive in each species in at least one of the 8 most frequent target sites: liver, lung, mammary gland, stomach, vascular system, kidney, hematopoietic system and urinary bladder. Species differences are discussed as well as results for particular target organs: liver, Zymbal's gland and kidney. C1 UNIV CALIF BERKELEY,DIV BIOCHEM & MOLEC BIOL,BERKELEY,CA 94720. UNIV SO CALIF,SCH MED,DEPT PREVENT MED,LOS ANGELES,CA 90033. RP GOLD, LS (reprint author), LAWRENCE BERKELEY LAB,DIV LIFE SCI,BERKELEY,CA 94720, USA. FU NIEHS NIH HHS [ESO1896] NR 35 TC 76 Z9 77 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8262 J9 MUTAT RES PD MAR PY 1993 VL 286 IS 1 BP 75 EP 100 DI 10.1016/0027-5107(93)90004-Y PG 26 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA KL502 UT WOS:A1993KL50200003 PM 7678909 ER PT J AU GURRIERI, F TRASK, BJ VANDENENGH, G KRAUSS, CM SCHINZEL, A PETTENATI, MJ SCHINDLER, D DIETZBAND, J VERGNAUD, G SCHERER, SW TSUI, LC MUENKE, M AF GURRIERI, F TRASK, BJ VANDENENGH, G KRAUSS, CM SCHINZEL, A PETTENATI, MJ SCHINDLER, D DIETZBAND, J VERGNAUD, G SCHERER, SW TSUI, LC MUENKE, M TI PHYSICAL MAPPING OF THE HOLOPROSENCEPHALY CRITICAL REGION ON CHROMOSOME-7Q36 SO NATURE GENETICS LA English DT Article ID UNBALANCED SEGREGATION; FAMILIAL TRANSLOCATION; POLYMORPHIC LOCI; DNA FRAGMENTS; LINKAGE MAP; CLONING; GENE; CYCLOPIA; MARKERS; PERSPECTIVES AB Holoprosencephaly (HPE) is a developmental field defect involving the brain and face. Cytogenetic deletions in patients with HPE have localized one of the HPE genes to chromosomal region 7q36. We have characterized the 7q deletions in thirteen HPE patients. The result is the construction of a high resolution physical map of 7q32-qter. As a first step towards cloning an HPE gene crucial for normal brain development, we have defined the HPE minimal critical region in 7q36 between D7S292 and D7S392. C1 CHILDRENS HOSP PHILADELPHIA,PHILADELPHIA,PA 19104. UNIV PENN,SCH MED,DEPT PEDIAT,DIV HUMAN GENET & MOLEC BIOL,PHILADELPHIA,PA 19104. LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,LIVERMORE,CA 94550. HARVARD COMMUNITY HLTH PLAN,BOSTON,MA 02116. INST MED GENET,ZURICH,SWITZERLAND. WAKE FOREST UNIV,BOWMAN GRAY SCH MED,DEPT PEDIAT,DIV MED GENET,WINSTON SALEM,NC 27103. INST HUMAN GENET & ANTHROPOL,WURZBURG,GERMANY. ONCOR INC,GAITHERSBURG,MD 20884. CTR ETUD BOUCHET,F-91710 VERT LE PETIT,FRANCE. HOSP SICK CHILDREN,DEPT GENET,TORONTO M5G 1X8,ONTARIO,CANADA. RI Tsui, Lap-chee/A-1081-2010; Howe, Jennifer/I-9013-2012; Scherer, Stephen /B-3785-2013; Vergnaud, Gilles/P-1304-2015; Gurrieri, Fiorella/K-3214-2016 OI Scherer, Stephen /0000-0002-8326-1999; Vergnaud, Gilles/0000-0003-0913-194X; Gurrieri, Fiorella/0000-0002-6775-5972 NR 36 TC 79 Z9 80 U1 0 U2 1 PU NATURE PUBLISHING CO PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 SN 1061-4036 J9 NAT GENET JI Nature Genet. PD MAR PY 1993 VL 3 IS 3 BP 247 EP 251 DI 10.1038/ng0393-247 PG 5 WC Genetics & Heredity SC Genetics & Heredity GA KP790 UT WOS:A1993KP79000015 PM 8485580 ER EF