FN Thomson Reuters Web of Science™ VR 1.0 PT J AU MATTSON, JE FULLERTON, EE SOWERS, CH HUANG, YY FELCHER, GP BADER, SD AF MATTSON, JE FULLERTON, EE SOWERS, CH HUANG, YY FELCHER, GP BADER, SD TI OSCILLATORY INTERLAYER MAGNETIC COUPLING OF SPUTTERED FE/NB SUPERLATTICES SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX SP AMER INST PHYS, IEEE, MAGNET SOC ID FE LAYERS; MAGNETORESISTANCE; MULTILAYERS; CO/RU AB The saturation field of sputtered Fe/Nb superlattices oscillates as a function of the Nb thickness with a periodicity of approximately 9 angstrom. In contrast to the case of Fe/Cr superlattices, the concurrent magnetoresistance oscillations were found to be very weak. Yet polarized neutron reflection measurements confirm that the Fe/Nb superlattices with high saturation field possess a magnetic ground state of the +-+- type. Neutron and x-ray measurements indicate that, while the crystalline and antiferromagnetic order is well developed along the thickness of the film, the average lateral size of the crystallites (as well as of the magnetic domains) is quite small. This effect (thought to be related to the gross mismatch of the iron and the niobium crystal lattices) may be the cause of the high overall resistance of the material, and its weak dependence on the magnetization. RP MATTSON, JE (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Bader, Samuel/A-2995-2013; Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 12 TC 13 Z9 13 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 5969 EP 5971 DI 10.1063/1.353486 PN 2A PG 3 WC Physics, Applied SC Physics GA LD854 UT WOS:A1993LD85400252 ER PT J AU YANG, YS GAULIN, BD FERNANDEZBACA, JA ALI, N WIGNALL, GD AF YANG, YS GAULIN, BD FERNANDEZBACA, JA ALI, N WIGNALL, GD TI SMALL-ANGLE NEUTRON-SCATTERING STUDIES OF CE(FE1-XALX)2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX SP AMER INST PHYS, IEEE, MAGNET SOC ID CEFE2 AB Ce(Fe1-xAlx)2, with x=0, 0.06, and 0.14, has been studied by small-angle neutron scattering in order to investigate the instability of the ferromagnetic state in the pure material to small amounts of magnetic disorder. The pure material (x=0) displays a ferromagnetic transition near T(C)=225 K, and more complicated behavior below approximately 100 K. The disordered alloys, x=0.06 and x=0.14, display ferromagnetic-like states over relatively narrow temperature ranges, and an additional low-temperature phase. The ferromagnetic-like state in the x=0.14 alloy appears to be qualitatively different from that exhibited by the other two. High-wave-vector-resolution measurements on the x=0.06 sample indicate that its low-temperature ordered phase is ferrimagnetic in origin. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. SO ILLINOIS UNIV,DEPT PHYS & MOLEC SCI,CARBONDALE,IL 62901. AECL RES,CHALK RIVER K0J 1J0,ON,CANADA. RP YANG, YS (reprint author), MCMASTER UNIV,DEPT PHYS & ASTRON,HAMILTON L8S 4M1,ONTARIO,CANADA. RI Piper, Walter/B-7908-2009; Fernandez-Baca, Jaime/C-3984-2014; OI Fernandez-Baca, Jaime/0000-0001-9080-5096; Wignall, George/0000-0002-3876-3244 NR 8 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6066 EP 6068 DI 10.1063/1.353471 PN 2A PG 3 WC Physics, Applied SC Physics GA LD854 UT WOS:A1993LD85400291 ER PT J AU LOONG, CK SODERHOLM, L HAMMONDS, JP ABRAHAM, MM BOATNER, LA EDELSTEIN, NM AF LOONG, CK SODERHOLM, L HAMMONDS, JP ABRAHAM, MM BOATNER, LA EDELSTEIN, NM TI NEUTRON STUDY OF CRYSTAL-FIELD TRANSITIONS IN ERPO4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX SP AMER INST PHYS, IEEE, MAGNET SOC ID ELECTRONIC RAMAN-SCATTERING; TMPO4; INTENSITIES; SPECTRA AB The crystal-field splitting of the Er3+ ground multiplet I-4(15/2) in ErPO4 is investigated by inelastic neutron scattering. Four excitations from the GAMMA7 ground state to the excited states and several transitions between the excited states have been identified. The observed transition energies and intensities are used to refine the parameters of the crystal-field potential. The calculated magnetic susceptibility chi(T) agrees well with experimental values from single-crystal measurements. A comparison of the neutron data with optical absorption and both nonresonance and resonance Raman scattering measurements has been made. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP LOONG, CK (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. RI Boatner, Lynn/I-6428-2013 OI Boatner, Lynn/0000-0002-0235-7594 NR 19 TC 10 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6069 EP 6071 DI 10.1063/1.353472 PN 2A PG 3 WC Physics, Applied SC Physics GA LD854 UT WOS:A1993LD85400292 ER PT J AU JOHNSON, SW ROBINSON, RA NAKOTTE, H BRUCK, E DEBOER, FR LARSON, AC AF JOHNSON, SW ROBINSON, RA NAKOTTE, H BRUCK, E DEBOER, FR LARSON, AC TI CRYSTALLOGRAPHIC AND MAGNETIC-PROPERTIES OF UPDSN SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX SP AMER INST PHYS, IEEE, MAGNET SOC AB A single crystal of the intermetallic compound UPdSn has been studied by means of neutron diffraction using the white-beam Laue diffractometer (single-crystal diffractometer) at the Los Alamos spallation neutron source. Data were taken in the paramagnetic phase at 55 K and just below the Neel point at 37 K. The crystallographic data refine well within the space group P6(3)mc and confirm the results obtained previously on powders, namely that the Pd and Sn atoms are ordered. At low temperature, UPdSn undergoes two phase transitions at 40 and 25 K to complicated noncollinear antiferromagnetic structures. All three pairs of magnetic domains are observed, in roughly equal populations, in the intermediate-temperature orthorhombic magnetic structure (phase I). A uranium moment of 0.863mu(B) and canting angles phi=56.51-degrees and theta=21.42-degrees were obtained, in reasonable agreement with previous powder neutron data for this temperature. The observed form factor yields an orbital-to-spin moment ratio -mu(L)/mu(S)=2.6 which is characteristic of the trivalent f3 configuration. C1 UNIV AMSTERDAM,VAN DER WAALS ZEEMAN LAB,1018 XE AMSTERDAM,NETHERLANDS. RP JOHNSON, SW (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Bruck, Ekkes/E-3365-2014 NR 8 TC 17 Z9 17 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6072 EP 6074 DI 10.1063/1.353473 PN 2A PG 3 WC Physics, Applied SC Physics GA LD854 UT WOS:A1993LD85400293 ER PT J AU KATSUMATA, K SHAPIRO, SM MATSUDA, M SHIRANE, G TUCHENDLER, J AF KATSUMATA, K SHAPIRO, SM MATSUDA, M SHIRANE, G TUCHENDLER, J TI A NEW-TYPE OF SPIN ORDERING IN A RANDOM MAGNET WITH COMPETING ANISOTROPIES SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX SP AMER INST PHYS, IEEE, MAGNET SOC ID QUENCHED RANDOM ALLOYS; DIFFERENT EASY AXES; ANTI-FERROMAGNETS; RANDOM MIXTURE; PHASE-TRANSITIONS; FE1-XCOXCL2; DIAGRAM; POINTS AB The result of an elastic neutron-scattering study of the phase transition in the random magnet with competing anisotropies Fe0.75Co0.25Br2 is reported. It was found that the ordering of the spin component parallel to the crystalline c axis at the transition from the paramagnetic to antiferromagnetic phase induces an ordering of the spin component perpendicular to it. Thus, there is no boundary separating the higher-temperature antiferromagnetic and lower-temperature mixed-ordering phase. This type of spin ordering is interpreted as arising from a coupling between the orthogonal spin components. C1 TOHOKU UNIV,DEPT PHYS,SENDAI,MIYAGI 980,JAPAN. BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV PARIS 06,DISPOSITIFS INFRAROUGE LAB,F-75252 PARIS 05,FRANCE. RP KATSUMATA, K (reprint author), INST PHYS & CHEM RES,WAKO,SAITAMA 35101,JAPAN. NR 23 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6084 EP 6086 DI 10.1063/1.353477 PN 2A PG 3 WC Physics, Applied SC Physics GA LD854 UT WOS:A1993LD85400297 ER PT J AU GOVINDARAJU, MR STROM, A JILES, DC BINER, SB CHEN, ZJ AF GOVINDARAJU, MR STROM, A JILES, DC BINER, SB CHEN, ZJ TI EVALUATION OF FATIGUE DAMAGE IN STEEL STRUCTURAL COMPONENTS BY MAGNETOELASTIC BARKHAUSEN SIGNAL ANALYSIS SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX AB This paper is concerned with using a magnetic technique for the evaluation of fatigue damage in steel structural components. It is shown that Barkhausen effect measurements can be used to indicate impending failure due to fatigue under certain conditions. The Barkhausen signal amplitude is known to be highly sensitive to changes in density and distribution of dislocations in materials. The sensitivity of Barkhausen signal amplitude to fatigue damage has been studied in the low-cycle fatigue regime using smooth tensile specimens of a medium strength steel. The Barkhausen measurements were taken at depths of penetration of 0.02, 0.07, and 0.2 mm. It was found that changes in magnetic properties are sensitive to microstructural changes taking place at the surface of the material throughout the fatigue life. The changes in the Barkhausen signals have been attributed to distribution of dislocations in stage I and stage II of fatigue life and the formation of a macrocrack in the final stage of fatigue. C1 IOWA STATE UNIV SCI & TECHNOL,CTR NDE,AMES,IA 50011. RP GOVINDARAJU, MR (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. RI Jiles, David/H-9548-2012 NR 13 TC 16 Z9 16 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6165 EP 6167 DI 10.1063/1.352737 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500007 ER PT J AU SABLIK, MJ KAMINSKI, DA JILES, DC BINER, SB AF SABLIK, MJ KAMINSKI, DA JILES, DC BINER, SB TI MAGNETIC PROPERTY VARIATION IN CARBON-STEEL AND CHROME-MOLYBDENUM STEEL AS A FUNCTION OF UNIAXIAL-STRESS NONCOAXIAL WITH THE MAGNETIC-FIELD SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. RP SABLIK, MJ (reprint author), SW RES INST,PO DRAWER 28510,SAN ANTONIO,TX 78228, USA. RI Jiles, David/H-9548-2012 NR 2 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6178 EP 6178 DI 10.1063/1.352688 PN 2B PG 1 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500012 ER PT J AU ZHANG, B KRISHNAN, KM LEE, CH FARROW, RFC AF ZHANG, B KRISHNAN, KM LEE, CH FARROW, RFC TI MAGNETIC-ANISOTROPY AND LATTICE STRAIN IN CO/PT MULTILAYERS SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID PD/CO AB The correlation is reported between perpendicular anisotropy and in-plane lattice strain in Co/Pt multilayers. (Co(x)/Pt(y))n samples, where x, y are the thickness of the individual Co and Pt layers and n is the number of repeats that were prepared by molecular beam epitaxy and studied by means of polar magneto-optic Kerr effect and transmission electron microscopy. Kerr rotation data and electron diffraction experiments show that the largest perpendicular anisotropy and square hysteresis loop occur when x = 3 angstrom while the Pt layers are subjected to about -2% in-plane strain. As Co thickness increases, Co and Pt layers gradually lose coherency and the magnetic anisotropy goes from perpendicular to planar. This is accompanied by a relaxation of lattice strain in both Co and Pt layers. The close relationship between magnetic anisotropy and lattice strain can be explained as magnetoelastic anisotropy or stress anisotropy effect due to lattice mismatch between the adjacent epitaxial layers. C1 IBM CORP,ALMADEN RES CTR,SAN JOSE,CA 95120. RP ZHANG, B (reprint author), LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720, USA. NR 11 TC 21 Z9 21 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6198 EP 6200 DI 10.1063/1.352696 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500020 ER PT J AU SODERHOLM, L LOONG, CK XUE, JS HAMMONDS, JP GREEDAN, JE MARIC, M AF SODERHOLM, L LOONG, CK XUE, JS HAMMONDS, JP GREEDAN, JE MARIC, M TI ELECTRONIC-TRANSITIONS OF HO IN PB2SR2HOCU3O8 OBSERVED BY INELASTIC NEUTRON-SCATTERING SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID CRYSTAL-FIELD; MODEL AB The electronic behavior of the I-5(8) Russell Saunders ground multiplet of Ho3+ in Pb2Sr2HoCu3O8 has been investigated using inelastic neutron scattering. We observe ten peaks in the excitation spectra that are associated with crystal field transitions. The peaks are only slightly broader than expected from instrument resolution, indicating that there are no strong interactions between the local Ho f states and the CuO conduction states. Comparing the energies and intensities of the experimental peaks with those expected from modeling convinces us that there are at least three states populated at the temperature of our experiment (15 K), making the assignments of transitions very difficult in the absence of further data. C1 MCMASTER UNIV,INST MAT RES,HAMILTON L8S 4M1,ONTARIO,CANADA. RP SODERHOLM, L (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 15 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6314 EP 6316 DI 10.1063/1.352684 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500062 ER PT J AU REYES, AP AHRENS, ET HAMMEL, PC THOMPSON, JD CANFIELD, PC FISK, Z HEFFNER, RH SCHIRBER, JE AF REYES, AP AHRENS, ET HAMMEL, PC THOMPSON, JD CANFIELD, PC FISK, Z HEFFNER, RH SCHIRBER, JE TI NQR STUDY OF LOCAL-STRUCTURE AND COOLING RATE-DEPENDENT SUPERCONDUCTIVITY IN LA2CUO4+DELTA SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID PHASE-SEPARATION; LA-139 AB Preliminary results of structural studies in oxygen-annealed La2CuO4+delta(delta approximately 0.03) using La-139 nuclear quadrupole resonance (NQR) spectroscopy are reported. Superconducting critical temperatures were found to depend on the rate of cooling through a narrow temperature range near 195 K. Analysis of the La-139 NQR spectra reveal that lanthanum atoms in the oxygen-rich metallic region occupy two sites having different local environments. One site has a structural configuration closely related to the stoichiometric oxygen-poor compound. The second appears only below 200 K and exhibits a large shift and broad distribution of NQR frequency nu(Q). Shifts in nu(Q) in the vicinity of the superconducting transition were also observed for both metallic sites. Possible origins of these anomalies and their connection to superconductivity are discussed. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP REYES, AP (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Canfield, Paul/H-2698-2014; Hammel, P Chris/O-4845-2014 OI Hammel, P Chris/0000-0002-4138-4798 NR 17 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6323 EP 6325 DI 10.1063/1.352634 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500065 ER PT J AU MATSUDA, M KURODA, K YAMADA, K ENDOH, Y CHOU, H SHIRANE, G BIRGENEAU, RJ KASTNER, MA TANAKA, I KOJIMA, H AF MATSUDA, M KURODA, K YAMADA, K ENDOH, Y CHOU, H SHIRANE, G BIRGENEAU, RJ KASTNER, MA TANAKA, I KOJIMA, H TI SPIN FLUCTUATIONS OF LA2-XSRXCU1-YZNYO4-DELTA (X=0.14, Y=0.012) SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. MIT,DEPT PHYS,CAMBRIDGE,MA 02139. YAMANASHI UNIV,FAC ENGN,INST INORGAN SYNTH,KOFU,YAMANASHI 400,JAPAN. RP MATSUDA, M (reprint author), TOHOKU UNIV,DEPT PHYS,SENDAI,MIYAGI 980,JAPAN. RI Yamada, Kazuyoshi/C-2728-2009; Tanaka, Isao/D-1519-2012 NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6333 EP 6333 DI 10.1063/1.352638 PN 2B PG 1 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500069 ER PT J AU FULLERTON, EE MATTSON, JE LEE, SR SOWERS, CH HUANG, YY FELCHER, G BADER, SD PARKER, FT AF FULLERTON, EE MATTSON, JE LEE, SR SOWERS, CH HUANG, YY FELCHER, G BADER, SD PARKER, FT TI MAGNETIC DECOUPLING IN SPUTTERED FE/SI SUPERLATTICES AND MULTILAYERS SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID EXCHANGE; PERIOD AB Sputtered Fe/Si superlattices were grown to study the magnetic coupling between ferromagnetic Fe layers (30 angstrom thick) for Si spacer-layer thicknesses (t(Si)) between 10 and 40 angstrom. The material is ferromagnetical for t(Si) < 13 angstrom and antiferromagnetically coupled for 13 angstrom < t(Si) < 17 angstrom. For t(Si) > 17 angstrom the Fe layers are uncoupled. X-ray analysis indicates that the system is well layered, but that the crystal structure remains coherent only for t(Si) < 17 angstrom. These results, along with our Mossbauer investigation, strongly suggest that the Si layer is crystalline for t(Si) < 17 angstrom, and is silicide in nature. For thicker spacers, Si becomes amorphous. We propose a model of the layering that is consistent with the known properties of Fe silicide. C1 UNIV CALIF SAN DIEGO,CTR MAGNET RECORDING RES 0401,LA JOLLA,CA 92093. KOREA UNIV,DEPT MET ENGN,SEOUL 136701,SOUTH KOREA. RP FULLERTON, EE (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Bader, Samuel/A-2995-2013; Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 23 TC 57 Z9 57 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6335 EP 6337 DI 10.1063/1.352640 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500071 ER PT J AU ROGGE, RB YANG, YS TUN, Z GAULIN, BD FERNANDEZBACA, JA NICKLOW, RM HARRISON, A AF ROGGE, RB YANG, YS TUN, Z GAULIN, BD FERNANDEZBACA, JA NICKLOW, RM HARRISON, A TI A NEUTRON-SCATTERING STUDY OF THE QUASI-ONE-DIMENSIONAL, DILUTE ISING-LIKE ANTIFERROMAGNET CSCO0.83MG0.17BR3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID CSCOBR3; SOLITONS; CSCOCL3 AB Neutron scattering measurements have been performed on a single-crystal sample of CSCo0.83Mg0.17Br3, a quasi-one-dimensional, Ising-like antiferromagnet. Residual three-dimensional interactions between the dilute magnetic chains precipitate a phase transition to long-range order at T(N) approximately 9.0 K, and short-range correlations persist as high as 40 K. Relatively high-energy inelastic scattering from both ''bulk'' spin-wave modes and ''end'' modes is observed from the finite chains. The low-energy inelastic spectrum is dominated by soliton scattering due to antiphase domain walls propagating along the finite chains. C1 AECL RES,CHALK RIVER LABS,CHALK RIVER K0J 1J0,ON,CANADA. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. UNIV OXFORD,INORGAN CHEM LAB,OXFORD OX1 3QR,ENGLAND. RP ROGGE, RB (reprint author), MCMASTER UNIV,DEPT PHYS & ASTRON,HAMILTON L8S 4M1,ONTARIO,CANADA. RI Piper, Walter/B-7908-2009; Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 11 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6451 EP 6453 DI 10.1063/1.352630 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500115 ER PT J AU WERNER, SA FAWCETT, E ELMIGER, MW SHIRANE, G AF WERNER, SA FAWCETT, E ELMIGER, MW SHIRANE, G TI HIGH-ENERGY SPIN-DENSITY-WAVE CORRELATED FLUCTUATIONS IN PARAMAGNETIC CR+5 AT-PERCENT-V SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID MAGNETIC EXCITATIONS; CHROMIUM; SCATTERING; ALLOYS AB Measurements of the magnetic fluctuations, termed spin-density-wave (SDW) paramagnons, in the nearly antiferromagnetic alloy Cr+5 at.% V are extended up in energy to about 80 meV. These fluctuating spin-spin correlations occur at incommensurate positions, corresponding to the SDW wave vector Q. Their characteristic energy is at least an order of magnitude larger than that of the magnetic fluctuations seen in the paramagnetic phase of pure Cr, but their intensity is more than two orders of magnitude smaller. We find that the dynamic susceptibility decreases by about 50% between temperature T= 10 and 300 K. C1 UNIV TORONTO,DEPT PHYS,TORONTO M5S 1A7,ONTARIO,CANADA. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP WERNER, SA (reprint author), UNIV MISSOURI,DEPT PHYS,COLUMBIA,MO 65211, USA. NR 13 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 MAY 15 PY 1993 VL 73 IS 10 BP 6454 EP 6456 DI 10.1063/1.352631 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500116 ER PT J AU CHANDRAMOULI, M THOMAS, G NELLIS, WJ AF CHANDRAMOULI, M THOMAS, G NELLIS, WJ TI SHOCK COMPACTION OF FE-ND-B SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX AB Shock compaction was performed using the 6.5-m-long two-stage light gas gun facility at LLNL on powders of Fe74Nd20B6, 10-20 mum in size which were prepared using conventional powder metallurgical techniques. The behavior of Fe-Nd-B powders and Fe-Nd-B powders blended with 10 vol. % Al was examined. X-ray-diffraction experiments detected no discernable difference in phase distribution or crystallinity when shock pressures below 100 kbar were applied to Fe-Nd-B powders alone and below 175 kbar for the case of the blended powders. After a 193 kbar shock was applied to Fe-Nd-B powder, only alpha-Fe was detected via x-ray diffraction. Scanning electron microscopy of shocked Fe-Nd-B indicated that a high degree of fracture occurred for pressures below 100 kbar. Indications of melting were observed in the 193 kbar sample along with a higher saturation magnetization as measured by vibrating sample magnetometry. Scanning electron microscopy of the Al-blended shocked specimens which are more dense revealed that very little fracture has occurred. C1 LAWRENCE LIVERMORE NATL LAB,IGPP,LIVERMORE,CA 94550. LAWRENCE LIVERMORE NATL LAB,MCSD,LIVERMORE,CA 94550. LAWRENCE LIVERMORE NATL LAB,NCEM,LIVERMORE,CA 94550. RP CHANDRAMOULI, M (reprint author), UNIV CALIF BERKELEY,DEPT MSME,BERKELEY,CA 94720, USA. NR 2 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6494 EP 6496 DI 10.1063/1.352591 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500130 ER PT J AU BENNETT, LH MCMICHAEL, RD SHULL, RD SWARTZENDRUBER, LJ WATSON, RE AF BENNETT, LH MCMICHAEL, RD SHULL, RD SWARTZENDRUBER, LJ WATSON, RE TI THE MAGNETOCALORIC EFFECT - THE ROLE OF MAGNETIC-ANISOTROPY SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID ROOM-TEMPERATURE; REFRIGERATION AB In a ferromagnet, the magnetic entropy change induced by the application of a magnetic field is greatest in the temperature regime near the Curie point. In the paramagnetic temperature regime, the magnitude of the magnetocaloric effect is expected to rise monotonically with the size of the individual moments that make up the material. The magnetic properties of such materials are relevant to devices employing magnetic refrigeration. One aspect of the problem, namely the impact of uniaxial magnetic anisotropy on the magnetocaloric effect, is explored. The results of Monte Carlo simulations for classical Heisenberg ferromagnets on a fcc lattice with anisotropy are presented. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RP BENNETT, LH (reprint author), NIST,GAITHERSBURG,MD 20899, USA. RI C, Y/G-5456-2010; McMichael, Robert/J-8688-2012; Shull, Robert/F-5971-2013; OI McMichael, Robert/0000-0002-1372-664X NR 13 TC 12 Z9 12 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 MAY 15 PY 1993 VL 73 IS 10 BP 6507 EP 6509 DI 10.1063/1.352596 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500135 ER PT J AU FERNANDEZBACA, JA HAGEN, ME NICKLOW, RM PERRING, TG TSUNODA, Y AF FERNANDEZBACA, JA HAGEN, ME NICKLOW, RM PERRING, TG TSUNODA, Y TI HIGH-ENERGY MAGNETIC EXCITATIONS IN MN90CU10 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID ITINERANT AB The study of the magnetic excitations in Mn-rich alloys should be a good test of the multiband calculations of the spin dynamics of pure gamma-Mn, which is a prototypical itinerant-electron antiferromagnet. In this paper we report the results of recent neutron inelastic scattering measurements performed on Mn90Cu10 at room temperature (T = 0.63T(N)) and up to 300 meV of energy transfer. These measurements were performed using the high-energy transfer (HET) chopper spectrometer at the ISIS spallation neutron source, Rutherford Appleton Laboratory, U.K. The results are in agreement with calculations using a model scattering function convoluted with the full HET resolution function. In this model there is a steep linear spin-wave dispersion ( D almost-equal-to 250 meV angstrom) for wave vectors up to almost-equal-to 1/2 of the Brillouin zone and a strong damping which is linear in the wave vector q. For larger wave vectors the spin-wave energies are constant at about 190 meV. These features are qualitatively similar to the predictions of Cade and Young for pure gamma-Mn. C1 UNIV KEELE,DEPT PHYS,KEELE ST5 5BG,STAFFS,ENGLAND. RUTHERFORD APPLETON LAB,ISIS,DIV SCI,DIDCOT OX11 0QX,OXON,ENGLAND. UNIV OSAKA,FAC SCI,OSAKA,JAPAN. RP FERNANDEZBACA, JA (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 8 TC 3 Z9 3 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6548 EP 6550 DI 10.1063/1.352559 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500152 ER PT J AU NAKOTTE, H BRUCK, E DEBOER, FR SVOBODA, P TUAN, NC HAVELA, L SECHOVSKY, V ROBINSON, RA AF NAKOTTE, H BRUCK, E DEBOER, FR SVOBODA, P TUAN, NC HAVELA, L SECHOVSKY, V ROBINSON, RA TI ANTIFERROMAGNETIC DOMAINS IN UPDSN SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX AB The magnetization of a single crystal of the hexagonal antiferromagnet UPdSn has been studied in fields up to 5 T in order to examine the energetics associated with antiferromagnetic domains. The magnetic unit cell is orthorhombic, so there are three possible domain orientations within the parent lattice. The low-temperature magnetization reflects both spin-flop transition and domain-depopulation effects. Although the interpretation of our results is complicated by the coexistence of these two phenomena, we can conclude that the domain occupancies are history dependent below the spin-reorientation transition which lies at 25 K, but history independent between this transition and T(N) = 40 K. Comparing magnetization results with those from previous neutron-diffraction studies, we propose a magnetic phase diagram for UPdSn. C1 CHARLES UNIV,DEPT MET PHYS,CS-12116 PRAGUE 2,CZECHOSLOVAKIA. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP NAKOTTE, H (reprint author), UNIV AMSTERDAM,VAN DER WAALS ZEEMAN LAB,VALCKENIERSTR 65,1018 XE AMSTERDAM,NETHERLANDS. RI Bruck, Ekkes/E-3365-2014; Sechovsky, Vladimir/A-5256-2008 OI Sechovsky, Vladimir/0000-0003-1298-2120 NR 4 TC 8 Z9 8 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6551 EP 6553 DI 10.1063/1.352560 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500153 ER PT J AU MONACHESI, P ANDREANI, LC CONTINENZA, A MCMAHAN, AK AF MONACHESI, P ANDREANI, LC CONTINENZA, A MCMAHAN, AK TI VOLUME DEPENDENCE OF ANDERSON HYBRIDIZATION IN CUBIC CECD AND CEAG SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID CERIUM COMPOUNDS; PRESSURE AB We have undertaken a first-principles theoretical study of the Anderson hybridization in cubic CeCd and CeAg as a function of volume reduction. We present results for the hybridization width DELTA (epsilon) in both the J = 5/2 multiplet and in the GAMMA8, GAMMA7 Crystal field states of the f1 Ce configuration. We also calculate the hybridization contribution to the magnetic transition temperature. This is found to increase with pressure but is smaller than the experimental values, indicating that the Coulomb exchange contribution to the magnetic coupling is not negligible in these compounds. C1 IRRMA,PHB ECUBLENS,CH-1015 LAUSANNE,SWITZERLAND. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP MONACHESI, P (reprint author), UNIV LAQUILA,DIPARTIMENTO FIS,I-67100 LAQUILA,ITALY. RI Continenza, Alessandra/M-1919-2015; OI Continenza, Alessandra/0000-0002-6169-2448; monachesi, patrizia/0000-0002-1267-3961 NR 13 TC 12 Z9 12 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 MAY 15 PY 1993 VL 73 IS 10 BP 6634 EP 6636 DI 10.1063/1.352537 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500184 ER PT J AU WADDILL, GD TOBIN, JG PAPPAS, DP AF WADDILL, GD TOBIN, JG PAPPAS, DP TI MAGNETIC-X-RAY DICHROISM IN 2P ABSORPTION-SPECTRA OF FE/CU(001) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX ID FCC-FE; FILMS; CU(100); TRANSITION; SURFACE; BCC; CO; NI AB Large magnetic circular dichroism using circularly polarized synchrotron radiation has been observed at the L2,3 absorption edges of thin ( 1-12 monolayers) fcc Fe films grown on Cu(001). Dramatic changes in the 2p branching ratio are observed when the orientation of photon helicity and sample magnetization are varied from parallel to antiparallel. The temperature and film thickness dependence of the perpendicular anisotropy in these films could be monitored by variations in the 2p branching ratio. Finally, our results are described in a simple theoretical framework that allows a determination between the predicted low- and high-spin phases for fcc Fe. Our data suggest a high-spin phase with a moment of 2.0-2.5 mu(B)/atom. Interestingly, thicker films with remanant magnetic moments in the film plane present smaller branching ratio variations consistent with either a reduced moment or with domain closure for these films. The surface sensitivity and elemental specificity of this technique make it particularly attractive for the study of surface and thin film magnetism. C1 USN,RES LAB,WASHINGTON,DC 20375. RP WADDILL, GD (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,POB 808,LIVERMORE,CA 94550, USA. RI Tobin, James/O-6953-2015 NR 29 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6748 EP 6750 DI 10.1063/1.352524 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500225 ER PT J AU CHA, YS AF CHA, YS TI ANALYSIS OF MAGNETIC ENERGY STORED IN SUPERCONDUCTING COILS WITH AND WITHOUT FERROMAGNETIC INSERTS SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX AB Inductance and energy of superconducting coils are calculated by (1) a long-solenoid approximation, (2) a finite-element model, and (3) working formulas and tables. The results of the finite-element model compare favorably with those of the working formulas. The long-solenoid approximation overpredicts the energy and inductance compared to the other two methods. The difference decreases with increasing length-to-diameter ratio. Energy stored in a coil with a ferromagnetic insert is calculated by using a long-solenoid approximation and a finite-element model. The analysis shows that the gain in energy ratio is equal to the relative permeability of the insert (which decreases with increasing current or current density). Even though large gains can be achieved at relatively low currents, the energy level itself is too low. The stored energy increases with current, but the gain decreases with increasing current because relative permeability decreases. If a coil with a diameter of 0.3 m and a length of 0.3 m is required to store 10 kJ of energy, the current density must equal 4000 A/cm 2. The gain in energy ratio is equal to 2.55 when the insert is used. RP CHA, YS (reprint author), ARGONNE NATL LAB,DIV MAT & COMPONENTS TECHNOL,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 1 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6787 EP 6789 DI 10.1063/1.352485 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500237 ER PT J AU CHEN, ZJ GOVINDARAJU, MR JILES, DC AF CHEN, ZJ GOVINDARAJU, MR JILES, DC TI ANALYTIC MODEL CALCULATION OF MAGNETIC-FIELD IN A MAGNETIC HALF-SPACE DUE TO SURFACE MAGNETIC CHARGE SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 37TH ANNUAL CONF ON MAGNETISM AND MAGNETIC MATERIALS CY DEC 01-04, 1992 CL HOUSTON, TX AB By analogy with electrostatic field, a simple analytic model is presented on the distribution of magnetic field inside a test material as a result of surface inspection with a magnetic probe. According to this model, the penetration depth of the magnetic field is defined and the permeability of the material at different depths is calculated. Finally, the magnetic flux inside the inspection head when placed on samples of different thicknesses is calculated and compared with experimental results. RP CHEN, ZJ (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. RI Jiles, David/H-9548-2012 NR 3 TC 2 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6858 EP 6860 DI 10.1063/1.352462 PN 2B PG 3 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500266 ER PT J AU GIBBS, D AF GIBBS, D TI X-RAY MAGNETIC SCATTERING - NEW DEVELOPMENTS SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract RP GIBBS, D (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS 510B,UPTON,NY 11973, USA. NR 0 TC 1 Z9 1 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 6883 EP 6883 DI 10.1063/1.352473 PN 2B PG 1 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500277 ER PT J AU FERNANDEZBACA, JA MOOK, HA AF FERNANDEZBACA, JA MOOK, HA TI SEARCH FOR THE BREAKDOWN OF THE SPIN-WAVE APPROXIMATION IN EUO SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract ID HEISENBERG RP FERNANDEZBACA, JA (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 3 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1993 VL 73 IS 10 BP 7023 EP 7023 DI 10.1063/1.354050 PN 2B PG 1 WC Physics, Applied SC Physics GA LD865 UT WOS:A1993LD86500327 ER PT J AU TADAKI, DK NIYOGI, SK AF TADAKI, DK NIYOGI, SK TI THE FUNCTIONAL IMPORTANCE OF HYDROPHOBICITY OF THE TYROSINE AT POSITION 13 OF HUMAN EPIDERMAL GROWTH-FACTOR IN RECEPTOR-BINDING SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID SITE-DIRECTED MUTAGENESIS; NUCLEAR-MAGNETIC-RESONANCE; KINASE-ACTIVITY; RESIDUES; EGF; LEUCINE-47; H-1-NMR; DOMAIN AB The tyrosine at position 13 of epidermal growth factor (EGF) has been implicated as playing a role in receptor binding due to its close proximity to the critical arginine 41 residue as well as its high degree of conservation in EGF and EGF-like proteins that can bind to the EGF receptor. Site-directed mutagenesis of tyrosine 13 in human EGF (hEGF) was employed to examine the role of this residue in ligand-receptor interaction. The removal of the hydroxyl moiety of the tyrosine by substitution with phenylalanine had little effect on the binding, indicating that it is not involved in any crucial hydrogen bonds with either the receptor or with other regions of the EGF molecule. The substitution of the aromatic tyrosine side-chain with the nonpolar leucine side-chain caused the receptor affinity to decrease only slightly, indicating that aromaticity of the amino acid at this site is also not critical. Substitutions with other hydrophobic residues, isoleucine, valine, and alanine, resulted in a significant decrease in receptor affinity as a function of decreasing hydrophobicity. Substitution of tyrosine 13 with the polar residues histidine and arginine markedly decreased receptor binding affinity, and complete removal of the side-chain by substitution with glycine dramatically lowered the binding affinity to 0.3% as compared to wild type. Analysis of three hEGF mutants, Tyr13-->Leu, Tyr13-->Arg, and Tyr13-->Gly, by circular dichroism showed that the major structural features of hEGF were not significantly altered. The results demonstrate that the decreased receptor affinities of these hEGF mutants are due to disruption of the functional contribution(s) of the tyrosine 13 residue rather than alteration(s) in the overall structural integrity. Overall, the results suggest that the tyrosine 13 side-chain plays a critical role in receptor binding by contributing to hydrophobic receptor-ligand interactions. C1 OAK RIDGE NATL LAB,DIV BIOL,UNIV TENNESSEE,OAK RIDGE GRAD SCH BIOMED SCI,POB 2009,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,PROTEIN ENGN & MOLEC MUTAGENESIS PROGRAM,OAK RIDGE,TN 37831. FU NCI NIH HHS [CA 50735] NR 33 TC 33 Z9 33 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 MAY 15 PY 1993 VL 268 IS 14 BP 10114 EP 10119 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA LB800 UT WOS:A1993LB80000028 PM 8486681 ER PT J AU WIEDMANN, RT WHITE, MG WANG, KH MCKOY, V AF WIEDMANN, RT WHITE, MG WANG, KH MCKOY, V TI SINGLE-PHOTON THRESHOLD PHOTOIONIZATION OF NO SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ENHANCED MULTIPHOTON IONIZATION; ROTATIONALLY RESOLVED PHOTOIONIZATION; PHOTOELECTRON ANGULAR-DISTRIBUTIONS; GAS-PHASE NO; NITRIC-OXIDE; KINETIC-ENERGY; DIATOMIC-MOLECULES; PROPENSITY RULES; RYDBERG STATES; SPECTROSCOPY AB Single-photon threshold photoionization spectra for jet-cooled NO have been measured for the v+ = 0 and 1 vibrational levels of the X 1SIGMA+ ground state of NO+. The NO+ rotational state distribution for the v+ = 0 level is shown to be perturbed by nearby autoionizing levels, whereas the v+ = 1 level exhibits a cation rotational distribution which is in near quantitative agreement with calculated spectra near threshold. Only small changes in total angular momentum are observed (\DELTAJ\ = \J+ -J''\ less-than-or-equal-to 5/2) even though a wide range of photoelectron angular momenta (l = 0-3) are predicted to contribute to the near-threshold photoelectron continua. The present results are also discussed in light of recently published two-photon threshold photoionization spectra of NO which exhibit nearly identical NO+ rotational state distributions. C1 CALTECH, ARTHUR AMOS NOYES LAB CHEM PHYS, PASADENA, CA 91125 USA. RP WIEDMANN, RT (reprint author), BROOKHAVEN NATL LAB, DEPT CHEM, UPTON, NY 11973 USA. NR 47 TC 21 Z9 21 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 15 PY 1993 VL 98 IS 10 BP 7673 EP 7679 DI 10.1063/1.464575 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LC870 UT WOS:A1993LC87000001 ER PT J AU GRABER, T KANTER, EP VAGER, Z ZAJFMAN, D AF GRABER, T KANTER, EP VAGER, Z ZAJFMAN, D TI CH2+ IS BENT SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID EXPLOSION AB The Coulomb explosion imaging (CEI) technique has been applied to a beam of vibrationally cold CH2+ molecular ions and the distribution of bond angles was extracted. From these data, we are able to demonstrate conclusively that the electronic ground state potential of this molecule has a C2v minimum and that the zero-point energy lies below the potential barrier to linearity. C1 WEIZMANN INST SCI, DEPT NUCL PHYS, IL-76100 REHOVOT, ISRAEL. UNIV ILLINOIS, DEPT PHYS, CHICAGO, IL 60680 USA. RP ARGONNE NATL LAB, DIV PHYS, ARGONNE, IL 60439 USA. NR 12 TC 10 Z9 10 U1 0 U2 1 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 MAY 15 PY 1993 VL 98 IS 10 BP 7725 EP 7729 DI 10.1063/1.465090 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LC870 UT WOS:A1993LC87000006 ER PT J AU FIGGIS, BN REYNOLDS, PA CABLE, JW AF FIGGIS, BN REYNOLDS, PA CABLE, JW TI EXTREME COVALENCE IN THE TC-CL BOND FROM POLARIZED NEUTRON-DIFFRACTION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SINGLE-CRYSTAL EPR; N-15 ENDOR; (PH4AS); DENSITY; CL-35; ESEEM AB A polarized neutron diffraction experiment on a salt containing the 4d1 TcNCl4- ion (S=1/2) yielded the flipping ratios of six reflections confined to the hk0 plane. Using nuclear structure factors, F(N), extrapolated from the 123 and 295 K x-ray structures, magnetic structure factors, F(M), were obtained from the flipping ratios. The values of F(M) were fitted to a model of spin populations in the Tc-4d and the Cl-3(sp) orbitals. It was found that 46(5)% of the spin density is located on the Cl atoms, corresponding to exceptionally high covalence in the Tc-Cl bonding. The amount is distinctly higher than found indirectly by ESR measurements, but is to some extent supported by a local density functional DV-Xalpha calculation. Because the data is limited to the one projection, it is not possible to separate the Tc and N spin density contributions. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. RP FIGGIS, BN (reprint author), UNIV WESTERN AUSTRALIA,DEPT CHEM,NEDLANDS,WA 6009,AUSTRALIA. NR 11 TC 11 Z9 12 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 15 PY 1993 VL 98 IS 10 BP 7743 EP 7745 DI 10.1063/1.464581 PG 3 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LC870 UT WOS:A1993LC87000008 ER PT J AU LOVEJOY, ER MOORE, CB AF LOVEJOY, ER MOORE, CB TI STRUCTURES IN THE ENERGY-DEPENDENCE OF THE RATE-CONSTANT FOR KETENE ISOMERIZATION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID UNIMOLECULAR REACTIONS; F+H2 REACTION; QUANTUM; PHOTOFRAGMENTATION; DYNAMICS; OXIRENE; REARRANGEMENT; FORMALDEHYDE; SCATTERING; CH2(X3B1) AB The isomerization of highly vibrationally excited and rotationally cold ketene has been investigated by monitoring the (CO)-C-12 and (CO)-C-13 dissociation products following laser excitation of jet-cooled (CH2)-C-12 (CO)-13, (CH2)-C-13 (CO)-C-12, and (CD2)-C-12 (CO)-C-13. The rate constants for the reactions (CH2)-C-12 (CO)-C-13 half arrow right over half arrow left (CH2)-C-13 (CO)-C-12 and (CD2)-C-12 half arrow right over half arrow left (CD2)-C-13 (CO)-C-12 are reported as a function of energy with a resolution of 1 cm-1. The rate constants exhibit pronounced peaks as a function of energy near the reaction threshold. This structure is attributed to quasistable motion along the reaction coordinate in the vicinity of the isomerization transition state. C1 LAWRENCE BERKELEY LAB, DIV MAT & CHEM SCI, BERKELEY, CA 94720 USA. RP LOVEJOY, ER (reprint author), UNIV CALIF BERKELEY, DEPT CHEM, BERKELEY, CA 94720 USA. NR 36 TC 56 Z9 56 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 MAY 15 PY 1993 VL 98 IS 10 BP 7846 EP 7854 DI 10.1063/1.464592 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LC870 UT WOS:A1993LC87000019 ER PT J AU DATSKOS, PG CHRISTOPHOROU, LG CARTER, JG AF DATSKOS, PG CHRISTOPHOROU, LG CARTER, JG TI TEMPERATURE-ENHANCED ELECTRON DETACHMENT FROM C6F6- NEGATIVE-IONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POLYATOMIC-MOLECULES; ATTACHMENT; PERFLUOROBENZENE; ENERGY; AFFINITIES; HEXAFLUOROBENZENE; SF6; N-2 AB A method is described whereby photoelectrons generated by a short laser pulse at the cathode of a parallel-plate electrode arrangement are depleted by attachment to C6F6 molecules mixed with N2 in the interelectrode space as they drift to the anode under an externally applied electric field. The contribution of the initially produced (prompt) and the delayed (autodetached from C6F6-) electrons to the induced signal in the detector circuit is recorded as a function of time following the laser pulse and also as a function of gas number density, applied electric field, and gas temperature, T. Increases in T from ambient to 575 K enhance dramatically the autodetachment frequency, tau(d)-1, for C6F6-. This heat-activated autodetachment correlates with the increase in the internal energy of the anion and has an activation energy of 0.477 eV. Electron attachment producing C6F6- initially increases slightly with increasing T below 500 K and subsequently decreases with further increases in T. C1 UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. RP DATSKOS, PG (reprint author), OAK RIDGE NATL LAB,ATOM MOLEC & HIGH VOLTAGE PHYS GRP,OAK RIDGE,TN 37831, USA. NR 39 TC 25 Z9 25 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 15 PY 1993 VL 98 IS 10 BP 7875 EP 7882 DI 10.1063/1.464595 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LC870 UT WOS:A1993LC87000022 ER PT J AU DURANT, JL ROHLFING, CM AF DURANT, JL ROHLFING, CM TI TRANSITION-STATE STRUCTURES AND ENERGETICS USING GAUSSIAN-2 THEORY SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POTENTIAL-ENERGY SURFACE; HIGHLY CORRELATED SYSTEMS; THEORETICAL CHARACTERIZATION; MOLECULAR-ENERGIES; 2ND-ROW COMPOUNDS; COMPUTED POINTS; ATOM ADDITION; DEFINE; PATH AB The availability of the easily implemented Gaussian-2 (G2) methodology has made it possible for the nonspecialist to calculate accurate heats of formation for many molecules on workstations. In order to quantify its performance for transition state structures, we have used G2 and a modified G2 on several transition states whose structures and energies have been well characterized either by experiment or multireference configuration interaction studies. The G2 method performs well in predicting energies of transition states (even for nonisogyric reactions), with an absolute average deviation of 1.5 kcal/mole in the classical barrier height for the cases studied, while it is less successful in predicting geometries and frequencies. We investigated modifying the G2 method for use with transition states by using QCISD/6-311 G (dp) geometries and frequencies instead of MP2/6-31G (d) geometries and scaled HF/6-31G(d) frequencies. The QCISD geometries and frequencies agree well with values from the literature, and this modified G2 procedure offers improved performance in predicting transition state energies. RP DURANT, JL (reprint author), SANDIA NATL LABS,CTR COMBUST & MAT SCI & TECHNOL,LIVERMORE,CA 94551, USA. NR 29 TC 104 Z9 104 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 15 PY 1993 VL 98 IS 10 BP 8031 EP 8036 DI 10.1063/1.464557 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LC870 UT WOS:A1993LC87000037 ER PT J AU XANTHEAS, SS DUNNING, TH AF XANTHEAS, SS DUNNING, TH TI THE STRUCTURE OF THE WATER TRIMER FROM ABINITIO CALCULATIONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SMALL CLUSTERS; VIBRATIONAL FREQUENCIES; MOLECULAR-INTERACTIONS; BASIS SETS; H2O; COMPLEXES; HYDROGEN; DIMER; DYNAMICS; ENERGIES AB The first fully optimized structure of the water trimer at the MP2 level of theory is reported. It corresponds to a cyclic chiral structure in which all O-O separations are equal to 2.80 angstrom, the O(alpha)H ... O(beta) hydrogen bonds are nonlinear, and two of the terminal hydrogens lie on one side of the O-O-O plane and the third lies on the other. This structure is in qualitative agreement with that reported recently by Pugliano and Saykally [Science 257, 1937 (1992)]. However, the calculations predict the O-O separations to be substantially shorter than those used to fit the far-infrared vibration-rotation-tunneling spectrum. Nonetheless, the computed structure reproduces the measured rotational constants of (D2O)3 ; the errors are < 1% for A and B and 6% for C An energy analysis yields a three-body term of 2.3 kcal/mol (approximately 15% of D(e) with respect to three isolated water molecules). RP XANTHEAS, SS (reprint author), PACIFIC NW LAB, THEORY MODELING & SIMULAT MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. RI Xantheas, Sotiris/L-1239-2015; OI Xantheas, Sotiris/0000-0002-6303-1037 NR 40 TC 210 Z9 211 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 MAY 15 PY 1993 VL 98 IS 10 BP 8037 EP 8040 DI 10.1063/1.464558 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LC870 UT WOS:A1993LC87000038 ER PT J AU BERETVAS, A BYONWAGNER, A FOSTER, GW FREEMAN, J GREEN, D HOJVAT, C TOKAREK, R ZHANG, G ZHOU, Y BARTOSZ, E HAGOPIAN, V WHITAKER, H GROOM, DE KADEL, RW GUSTAFSON, R LEGGETT, C SHAPPIRIO, M HUSTON, J CREMALDI, L REIDY, J SUMMERS, D BARNES, VE DEBARBARO, P BODEK, A BUDD, H FAN, Q SAKUMOTO, WK WALKER, R ZHAO, C AF BERETVAS, A BYONWAGNER, A FOSTER, GW FREEMAN, J GREEN, D HOJVAT, C TOKAREK, R ZHANG, G ZHOU, Y BARTOSZ, E HAGOPIAN, V WHITAKER, H GROOM, DE KADEL, RW GUSTAFSON, R LEGGETT, C SHAPPIRIO, M HUSTON, J CREMALDI, L REIDY, J SUMMERS, D BARNES, VE DEBARBARO, P BODEK, A BUDD, H FAN, Q SAKUMOTO, WK WALKER, R ZHAO, C TI BEAM TESTS OF COMPOSITE CALORIMETER CONFIGURATIONS FROM RECONFIGURABLE-STACK CALORIMETER SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID SCINTILLATOR CALORIMETER; HADRON CALORIMETER; LIQUID-ARGON; PERFORMANCE; ELECTRON; DETECTOR; CERN AB The energy resolution, linearity and e/pi response of model SDC calorimeter configurations were measured. They consisted of a fine sampling lead electromagnetic (e.m.) compartment and either a lead or iron hadronic (HAD) compartment. The data indicate that the lead-scintillator and iron-scintillator hadronic calorimeters have comparable resolutions and linearity after a relative weighting of signals from the EM and HAD compartments is made. C1 FLORIDA STATE UNIV,TALLAHASSEE,FL 32306. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV MICHIGAN,ANN ARBOR,MI 48109. UNIV MISSISSIPPI,UNIVERSITY,MS 38677. PURDUE UNIV,W LAFAYETTE,IN 47907. UNIV ROCHESTER,ROCHESTER,NY 14627. UNIV WISCONSIN,MADISON,WI 53706. RP BERETVAS, A (reprint author), FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. NR 26 TC 6 Z9 7 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 MAY 15 PY 1993 VL 329 IS 1-2 BP 50 EP 61 DI 10.1016/0168-9002(93)90922-5 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ781 UT WOS:A1993KZ78100008 ER PT J AU FRABETTI, PL BOGART, CW CUMALAT, J CULY, S CHEUNG, H JOHNS, W BUTLER, JN CIHANGIR, S CURRIER, R DAVENPORT, F GAINES, I GARBINCIUS, PH GOURLAY, S HARDING, DJ JUSTICE, R KASPER, P KREYMER, A LEBRUN, P SHUKLA, S BIANCO, S FABBRI, FL SPALLONE, A ZALLO, A JAROSS, G LINGEL, K WISS, J ALIMONTI, G BELLINI, G CACCIANIGA, B GAVALETTI, WR CINQUINI, L DANGELO, P DICORATO, M GIAMMARCHI, M INZANI, P LEVERARO, F MALVEZZI, S MANFREDI, PF MENASCE, D MERONI, E MORONI, L PEDRINI, D PERASSO, L RAGUSA, F SALA, A SALA, S TORETTA, D VITTONE, M BUCHHOLZ, D CASTOLDI, C CLAES, D GOBBI, B PARK, S YOSHIDA, R BISHOP, JM BUSENITZ, JK CASON, NM CUNNINGHAM, JD GARDNER, RW KENNEDY, CJ MANNEL, EJ MOUNTAIN, RJ PUSELJIC, DL RUCHTI, RC SHEPHARD, WD WU, ZY ZANABRIA, ME ARENA, V BOCA, G DIAFERIA, R RATTI, SP RICCARDI, C VITULO, P LOPEZ, A MENDEZ, H WILSON, JR AF FRABETTI, PL BOGART, CW CUMALAT, J CULY, S CHEUNG, H JOHNS, W BUTLER, JN CIHANGIR, S CURRIER, R DAVENPORT, F GAINES, I GARBINCIUS, PH GOURLAY, S HARDING, DJ JUSTICE, R KASPER, P KREYMER, A LEBRUN, P SHUKLA, S BIANCO, S FABBRI, FL SPALLONE, A ZALLO, A JAROSS, G LINGEL, K WISS, J ALIMONTI, G BELLINI, G CACCIANIGA, B GAVALETTI, WR CINQUINI, L DANGELO, P DICORATO, M GIAMMARCHI, M INZANI, P LEVERARO, F MALVEZZI, S MANFREDI, PF MENASCE, D MERONI, E MORONI, L PEDRINI, D PERASSO, L RAGUSA, F SALA, A SALA, S TORETTA, D VITTONE, M BUCHHOLZ, D CASTOLDI, C CLAES, D GOBBI, B PARK, S YOSHIDA, R BISHOP, JM BUSENITZ, JK CASON, NM CUNNINGHAM, JD GARDNER, RW KENNEDY, CJ MANNEL, EJ MOUNTAIN, RJ PUSELJIC, DL RUCHTI, RC SHEPHARD, WD WU, ZY ZANABRIA, ME ARENA, V BOCA, G DIAFERIA, R RATTI, SP RICCARDI, C VITULO, P LOPEZ, A MENDEZ, H WILSON, JR TI A WIDE-BAND PHOTON-BEAM AT THE FERMILAB TEVATRON TO STUDY HEAVY FLAVORS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB For many years, the use of high energy photon beams has been recognized as a good technique for the investigation of charmed particles [1]. The cross section is a relatively large fraction (approximately 1%) of the total hadronic cross section at high energies. The challenge was to develop a high energy and high intensity beam that produces enough charmed particles to obtain very high statistics so that one can answer detailed questions about charm production and decays. The Fermilab wide band photon beam is an attempt to meet that challenge. The beamline configuration and capabilities have evolved since the test run in 1985 and the first physics run in 1987-88. For the 1990-91 data run, improvements were made to increase the photon yield and to improve the photon energy tagging resolution. Althought the main emphasis of this report is on the original 1985-88 beam configuration, two fully operational upgrades for the 1990-91 run, namely the incident electron beam momentum tagging spectrometer and the LD2 primary beam target, are described. The beam was also given the capability of transporting simultaneously e+ and e- beams. The performance of this ''double-band'' configuration was studied briefly duing the 1990-91 running period and will be described in a future publication. A description of the Fermilab E687 spectrometer utilizing this photon beam facility has recently been published [2]. C1 INFN BOLOGNA,I-40126 BOLOGNA,ITALY. UNIV COLORADO,BOULDER,CO 80309. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. LAB NAZL FRASCATI,I-00044 PRASCATI,ITALY. UNIV ILLINOIS,URBANA,IL 61801. INFN MILANO,I-20133 MILAN,ITALY. UNIV MILAN,DIPARTIMENTO FIS,I-20133 MILAN,ITALY. NORTHWESTERN UNIV,EVANSTON,IL 60208. UNIV NOTRE DAME,NOTRE DAME,IN 46556. UNIV PAVIA,DIPARTIMENTO FIS NUCL & TEOR,I-27100 PAVIA,ITALY. INFN PAVIA,I-27100 PAVIA,ITALY. UNIV PUERTO RICO,MAYAGUEZ,PR 00708. CINVESTAV IPN,MEXICO CITY 07000,DF,MEXICO. UNIV S CAROLINA,COLUMBIA,SC 29208. RP FRABETTI, PL (reprint author), UNIV BOLOGNA,DIPARTIMENTO FIS,I-40126 BOLOGNA,ITALY. RI Menasce, Dario Livio/A-2168-2016; OI Menasce, Dario Livio/0000-0002-9918-1686; bianco, stefano/0000-0002-8300-4124 NR 18 TC 33 Z9 33 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 MAY 15 PY 1993 VL 329 IS 1-2 BP 62 EP 78 DI 10.1016/0168-9002(93)90923-6 PG 17 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ781 UT WOS:A1993KZ78100009 ER PT J AU BARBER, DP BREMER, HD BOGE, M BRINKMANN, R BRUCKNER, W BUSCHER, C CHAPMAN, M COULTER, K DELHEIJ, PPJ DUREN, M GIANFELICEWENDT, E GREEN, PEW GAUL, HG GRESSMANN, H HAUSSER, O HENDERSON, R JANKE, T KAISER, H KAISER, R KITCHING, P KLANNER, R LEVY, P LEWIN, HC LOMPERSKI, M LORENZON, W LOSEV, L MCKEOWN, RD MEYNERS, N MICHEEL, B MILNER, R MUCKLICH, A NEUNREITHER, F NOWAK, WD PATEL, PM RITH, K SCHOLZ, C STEFFENS, E VELTRI, M VETTERLI, M VOGEL, W WANDER, W WESTPHAL, D ZAPFE, K ZETSCHE, F AF BARBER, DP BREMER, HD BOGE, M BRINKMANN, R BRUCKNER, W BUSCHER, C CHAPMAN, M COULTER, K DELHEIJ, PPJ DUREN, M GIANFELICEWENDT, E GREEN, PEW GAUL, HG GRESSMANN, H HAUSSER, O HENDERSON, R JANKE, T KAISER, H KAISER, R KITCHING, P KLANNER, R LEVY, P LEWIN, HC LOMPERSKI, M LORENZON, W LOSEV, L MCKEOWN, RD MEYNERS, N MICHEEL, B MILNER, R MUCKLICH, A NEUNREITHER, F NOWAK, WD PATEL, PM RITH, K SCHOLZ, C STEFFENS, E VELTRI, M VETTERLI, M VOGEL, W WANDER, W WESTPHAL, D ZAPFE, K ZETSCHE, F TI THE HERA POLARIMETER AND THE 1ST OBSERVATION OF ELECTRON-SPIN POLARIZATION AT HERA SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID ENERGY STORAGE-RINGS; BEAM POLARIZATION; SCATTERING; PHOTONS; MASS; LEP AB Electron spin polarizations of about 8% were observed at HERA in November 1991. In runs during 1992, utilizing special orbit corrections, polarization values close to 60% have been achieved. In this paper the polarimeter, the machine conditions, the data analysis, the first results and plans for future measurements are described. C1 MAX PLANCK INST NUCL PHYS,W-6900 HEIDELBERG 1,GERMANY. TRIUMF,VANCOUVER,BC,CANADA. MIT,BOSTON,MA. ARGONNE NATL LAB,ARGONNE,IL 60439. LEBEDEV PHYS INST,MOSCOW,RUSSIA. UNIV ALBERTA,EDMONTON T6G 2E1,ALBERTA,CANADA. DESY,INST HOCHENERGIEPHYS,ZEUTHEN,GERMANY. SIMON FRASER UNIV,VANCOUVER,BC,CANADA. UNIV WISCONSIN,MADISON,WI 53706. UNIV HAMBURG,W-2000 HAMBURG 13,GERMANY. UNIV MUNSTER,W-4400 MUNSTER,GERMANY. MCGILL UNIV,MONTREAL H3A 2T5,QUEBEC,CANADA. CALTECH,PASADENA,CA 91125. RP BARBER, DP (reprint author), DESY,W-2000 HAMBURG 52,GERMANY. RI Chapman, Michael/C-1929-2014; Losev, Leonid/M-4058-2015 OI Chapman, Michael/0000-0003-4424-0156; NR 46 TC 82 Z9 83 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 MAY 15 PY 1993 VL 329 IS 1-2 BP 79 EP 111 DI 10.1016/0168-9002(93)90924-7 PG 33 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ781 UT WOS:A1993KZ78100010 ER PT J AU INNES, WR AF INNES, WR TI SOME FORMULAS FOR ESTIMATING TRACKING ERRORS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID SCATTERING AB Universal curves and approximate formulas for the elements of the track parameter error matrix are derived for homogeneous tracking detectors in the continuous measurement limit. RP INNES, WR (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 5 TC 7 Z9 7 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 MAY 15 PY 1993 VL 329 IS 1-2 BP 238 EP 242 DI 10.1016/0168-9002(93)90942-B PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ781 UT WOS:A1993KZ78100028 ER PT J AU BARLETTA, WA BELLOMO, G BONIFACIO, R CORSINI, R DESALVO, L PIERINI, P PULLIA, M AF BARLETTA, WA BELLOMO, G BONIFACIO, R CORSINI, R DESALVO, L PIERINI, P PULLIA, M TI AN RF-LINAC, FEL BUNCHER SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID FREE-ELECTRON LASER AB We describe a means of producing a train of 40 kA pulses of 3 ps duration as the drive beam for CLIC using an rf linac driven free electron laser (FEL) buncher. Potential debunching effects are discussed. Finally we describe a low energy test experiment. C1 UNIV MILAN,I-20133 MILAN,ITALY. UNIV CALIF LOS ANGELES,DEPT PHYS,LOS ANGELES,CA 90024. INFN,I-20133 MILAN,ITALY. RP BARLETTA, WA (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. RI Pierini, Paolo/J-3555-2012 OI Pierini, Paolo/0000-0002-3062-6181 NR 11 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 15 PY 1993 VL 329 IS 1-2 BP 348 EP 360 DI 10.1016/0168-9002(93)90953-F PG 13 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ781 UT WOS:A1993KZ78100039 ER PT J AU FOURKAS, JT TREBINO, R DUGAN, MA FAYER, MD AF FOURKAS, JT TREBINO, R DUGAN, MA FAYER, MD TI EXTRA RESONANCES IN TIME-DOMAIN 4-WAVE-MIXING SO OPTICS LETTERS LA English DT Article ID DEGENERATE FREQUENCY RESONANCE; SPECTROSCOPY AB We show that extra resonances, such as those caused in frequency-domain nonlinear wave mixing by pure dephasing or laser fluctuations, can also be induced by operation in the time domain. These pulse-length-induced extra resonances arise in transient-grating experiments when the laser pulses are short enough that a steady state cannot be achieved during the excitation process. We show theoretically that these resonances increase in strength with decreasing excitation pulse length until the pulse length becomes shorter than the dephasing time of the medium and quote an experimental example to support this interpretation. C1 SANDIA NATL LABS,COMBUST RES FACIL,LIVERMORE,CA 94451. STANFORD UNIV,DEPT CHEM,STANFORD,CA 94305. RP FOURKAS, JT (reprint author), UNIV TEXAS,DEPT CHEM & BIOCHEM,AUSTIN,TX 78712, USA. RI Fourkas, John/B-3500-2009 OI Fourkas, John/0000-0002-4522-9584 NR 13 TC 2 Z9 2 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAY 15 PY 1993 VL 18 IS 10 BP 781 EP 783 DI 10.1364/OL.18.000781 PG 3 WC Optics SC Optics GA LA947 UT WOS:A1993LA94700009 PM 19802271 ER PT J AU KANE, DJ TREBINO, R AF KANE, DJ TREBINO, R TI SINGLE-SHOT MEASUREMENT OF THE INTENSITY AND PHASE OF AN ARBITRARY ULTRASHORT PULSE BY USING FREQUENCY-RESOLVED OPTICAL GATING SO OPTICS LETTERS LA English DT Article ID RETRIEVAL; CHIRP; RECONSTRUCTION; AMPLITUDE AB We introduce a new technique, frequency-resolved optical gating, for measuring the intensity I(t) and the phase phi(t) of an individual arbitrary ultrashort pulse. Using an instantaneous nonlinear-optical interaction of two variably delayed replicas of the pulse, frequency-resolved optical gating involves measuring the spectrum of the signal pulse versus relative delay. The resulting trace, a spectrogram, yields an intuitive full-information display of the pulse. Inversion of this trace to obtain the pulse intensity and phase is equivalent to the well-known two-dimensional phase-retrieval problem and thus yields essentially unambiguous results for I(t) and phi(t). C1 SANDIA NATL LABS,COMBUST RES FACIL,LIVERMORE,CA 94551. RP KANE, DJ (reprint author), SW SCI INC,SUITE E-11,1570 PACHECO ST,SANTA FE,NM 87501, USA. NR 28 TC 298 Z9 302 U1 9 U2 55 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAY 15 PY 1993 VL 18 IS 10 BP 823 EP 825 DI 10.1364/OL.18.000823 PG 3 WC Optics SC Optics GA LA947 UT WOS:A1993LA94700023 PM 19802285 ER PT J AU SENNAROGLU, A POLLOCK, CR NATHEL, H AF SENNAROGLU, A POLLOCK, CR NATHEL, H TI GENERATION OF 48-FS PULSES AND MEASUREMENT OF CRYSTAL DISPERSION BY USING A REGENERATIVELY INITIATED SELF-MODE-LOCKED CHROMIUM-DOPED FORSTERITE LASER SO OPTICS LETTERS LA English DT Article ID TI-SAPPHIRE LASER AB A regeneratively initiated self-mode-locked chromium-doped forsterite laser operated at 3.5-degrees-C is described. By employing intracavity negative-group-velocity dispersion compensation, nearly transform-limited femtosecond pulses of 48-fs (FWHM) duration were generated with average TEM00 output powers of 380 mW at 1.23 mum. Regenerative initiation provides improvement in the output stability and ease of operation compared with fixed-frequency acousto-optic modulators. By tuning the mode-locked laser in the range 1.21-1.26 mum, estimated values for forsterite dispersion constants have also been obtained for the first time to our knowledge. The demonstrated power and stability open the door to applications such as efficient second-harmonic generation. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP SENNAROGLU, A (reprint author), CORNELL UNIV,SCH ELECT ENGN,ITHACA,NY 14853, USA. NR 12 TC 34 Z9 34 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAY 15 PY 1993 VL 18 IS 10 BP 826 EP 828 DI 10.1364/OL.18.000826 PG 3 WC Optics SC Optics GA LA947 UT WOS:A1993LA94700024 PM 19802286 ER PT J AU YOO, SI MCCALLUM, RW AF YOO, SI MCCALLUM, RW TI PHASE-DIAGRAM IN THE ND-BA-CU-O SYSTEM SO PHYSICA C LA English DT Article ID CRYSTAL-CHEMISTRY; 950-DEGREES-C; Y2O3-BAO-CUO; SUPERCONDUCTIVITY; COMPATIBILITIES; EQUILIBRIA; REGION; SM; EU; GD AB The subsolidus phase relationship in the Nd-Ba-Cu-O system has been investigated at 890-degrees-C in air. In this study, the discrepancies in the published phase diagrams of this system have been clarified. For the BaO-rich region, CO2-free (CO2 < 3 ppm) air was necessary to synthesize equilibrium phases. Significant results include determination of the solubility limits of 0.04 less-than-or-equal-to x less-than-or-equal-to 0.6 in Nd1+xBa2-xCu3O7+delta, the existence of a Nd2BaCuO10 solid solution, and discovery of a new phase, NdBa6Cu3Oy, in the BaO-rich region. RP YOO, SI (reprint author), US DOE,AMES LAB,AMES,IA 50011, USA. RI Yoo, Sang-Im/C-8565-2014 NR 25 TC 155 Z9 155 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 15 PY 1993 VL 210 IS 1-2 BP 147 EP 156 DI 10.1016/0921-4534(93)90019-M PG 10 WC Physics, Applied SC Physics GA LE084 UT WOS:A1993LE08400017 ER PT J AU YOO, SI MCCALLUM, RW AF YOO, SI MCCALLUM, RW TI FLUX-CREEP IN ND1+XBA2-XCU3O7+DELTA (X=0.0-0.1) SO PHYSICA C LA English DT Article ID YBA2CU3O7; CRYSTAL; IRREVERSIBILITY; CURRENTS AB Among the REBa2Cu3O7 superconductors, RE=Nd is particularly interesting in that there exists a solid solution Nd1+xBa2-xCu3O7+delta with the solubility limit of 0.04 less-than-or-equal-to x less-than-or-equal-to 0.6 at 890-degrees-C in air and superconductivity appears up to x almost-equal-to 0.4 when it is oxygen-annealed. The substitution of Nd3+ for Ba2+ in Nd1+xBa2-xCu3O7+delta increases the occupation of O(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. While T(c) is not affected over the range 0.0 less-than-or-equal-to x less-than-or-equal-to 0. 1, the oxygens surrounding the substituted Ba sites are expected to locally suppress the superconducting order parameter. Such a local suppression of the order parameter may be expected to act as a pinning site for magnetic flux enhancing the critical current density. Hysteresis measurements exhibited a small increase in the magnetic J(c), but flux creep measurements on high quality powdered and aligned samples of Nd1+xBa2-xCu3O7+delta with 0.0 less-than-or-equal-to x less-than-or-equal-to 0. 1 showed no apparent effects of this substitution on the flux pinning energy. RP YOO, SI (reprint author), US DOE,AMES LAB,AMES,IA 50011, USA. RI Yoo, Sang-Im/C-8565-2014 NR 25 TC 22 Z9 22 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 15 PY 1993 VL 210 IS 1-2 BP 157 EP 163 DI 10.1016/0921-4534(93)90020-Q PG 7 WC Physics, Applied SC Physics GA LE084 UT WOS:A1993LE08400018 ER PT J AU GOYAL, A ALEXANDER, KB KROEGER, DM FUNKENBUSCH, PD BURNS, SJ AF GOYAL, A ALEXANDER, KB KROEGER, DM FUNKENBUSCH, PD BURNS, SJ TI SOLIDIFICATION OF YBA2CU3O7-DELTA FROM THE MELT SO PHYSICA C LA English DT Article ID SINGLE-CRYSTALS; CURRENT-DENSITY; SUPERCONDUCTOR; MICROSTRUCTURE; GROWTH; YBA2CU3O6+X AB Nucleation and growth of 123 from the melt via a peritectic reaction into domains of aligned platelets is studied. Analysis of the microstructure of well-formed domains indicates that there is no orientation difference between adjacent platelets within a domain, suggesting that a domain grows from a single nucleus. The platelet boundaries are found to be filled-in with secondary phases that correspond to the liquid phase at high temperature, suggesting that constitutional supercooling effects may be operative. Samples quenched from temperatures considerably below the peritectic temperature contain only a few crystals, indicating the presence of a large nucleation barrier. The above observations, coupled with extensive microstructural examination of quenched solid-liquid interfaces, suggest that the 211 size, distribution and volume fraction not only control the growth rate of 123 along the fast growth ab-plane (by supply of yttrium), but also the growth rate along the slow growth c-direction since the nucleation barrier is reduced at 211/123 intersections. At high cooling rates there is a distinct change in the nucleation and growth processes. Structures characteristic of sympathetic or autonucleation and spherulitic growth are observed. These structures are distinct from the single crystal nature of well-formed domains. The growth mechanism which results in the formation of 123 domains and the final microstructure within a single domain, also explains the observed non-weak-link characteristics for current flow along the a, b- and c-directions, as determined by direct transport and magnetization measurements. C1 UNIV ROCHESTER,DEPT MECH ENGN,MAT SCI PROGRAM,ROCHESTER,NY 14627. RP GOYAL, A (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831, USA. NR 35 TC 84 Z9 84 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 15 PY 1993 VL 210 IS 1-2 BP 197 EP 212 DI 10.1016/0921-4534(93)90025-L PG 16 WC Physics, Applied SC Physics GA LE084 UT WOS:A1993LE08400023 ER PT J AU HU, JG MILLER, DJ SCHULZ, DL HAN, B NEUMAYER, DA HINDS, BJ MARKS, TJ AF HU, JG MILLER, DJ SCHULZ, DL HAN, B NEUMAYER, DA HINDS, BJ MARKS, TJ TI TRANSMISSION ELECTRON-MICROSCOPIC CHARACTERIZATION OF METAL-ORGANIC CHEMICAL-VAPOR DEPOSITION-DERIVED SUPERCONDUCTING TL2BA2CA1CU2OX THIN-FILMS ON AU-SUBSTRATES - EVIDENCE FOR AU-CU ALLOY FORMATION AND TEXTURING ON A NONPLANAR METAL-SUBSTRATE SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; O FILMS; YBA2CU3O7-X; SILVER; OXIDE AB The microstructure of superconducting Tl2Ba2CaCu2Ox thin films grown on Au substrates by metal-organic chemical vapor deposition (MOCVD) has been investigated. Characterization techniques included X-ray diffraction, variable temperature magnetization, scanning and transmission electron microscopy (SEM and TEM, respectively) and energy dispersive X-ray spectroscopy (EDX) measurements. The films exhibit a magnetically derived T(c) almost-equal-to 80 K and a high degree of texturing with the crystallite c-axes oriented perpendicular to the Au substrate surface as evidenced by enhanced (001) X-my diffraction reflections. SEM/EDX and TEM/EDX provide evidence of Au-Cu alloy formation but no Au diffusion into the film. The superconducting grains exhibit good compositional uniformity and excellent alignment with the substrate, even though the Au substrates were not smooth and exhibited a moderate density of steps. C1 ARGONNE NATL LAB, CTR SCI & TECHNOL SUPERCOND, ARGONNE, IL 60439 USA. NORTHWESTERN UNIV, DEPT CHEM, EVANSTON, IL 60208 USA. NORTHWESTERN UNIV, CTR SCI & TECHNOL SUPERCOND, EVANSTON, IL 60208 USA. RP HU, JG (reprint author), ARGONNE NATL LAB, DIV MAT SCI, ARGONNE, IL 60439 USA. NR 41 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD MAY 15 PY 1993 VL 210 IS 1-2 BP 97 EP 105 DI 10.1016/0921-4534(93)90012-F PG 9 WC Physics, Applied SC Physics GA LE084 UT WOS:A1993LE08400010 ER PT J AU ROOS, KR TRINGIDES, MC AF ROOS, KR TRINGIDES, MC TI REFLECTION HIGH-ENERGY-ELECTRON-DIFFRACTION STUDIES OF MASS-TRANSPORT AND LOW-TEMPERATURE GROWTH OF AG/SI(111) SO PHYSICAL REVIEW B LA English DT Article ID EPITAXIAL-GROWTH; OSCILLATIONS; DYNAMICS; GAAS; MBE AB We have studied the growth modes and mass-transport mechanism of the Ag/Si(111) system by using reflection high-energy-electron-diffraction quantitative spot analysis. The growth mode at 150 K is quasi-layer-by-layer, indicating significant adatom mobility. The scaling of the specular beam intensity with time for several deposition rates suggests the absence of thermally activated diffusion. The presence of nonthermal diffusion is further confirmed from the comparison of the initial growth rates and the final full width at half maximum attained at different deposition rates for the Ag/Si(111)-(square-root 3 X square-root 3)R 30-degrees system. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. RP ROOS, KR (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 14 TC 15 Z9 15 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1993 VL 47 IS 19 BP 12705 EP 12708 DI 10.1103/PhysRevB.47.12705 PG 4 WC Physics, Condensed Matter SC Physics GA LE966 UT WOS:A1993LE96600035 ER PT J AU RAVELO, R ELBATANOUNY, M AF RAVELO, R ELBATANOUNY, M TI MOLECULAR-DYNAMICS STUDIES OF TEMPERATURE-DEPENDENT STRUCTURAL TRANSITIONS ON FCC(111) METALLIC SURFACES SO PHYSICAL REVIEW B LA English DT Article ID COMMENSURATE-INCOMMENSURATE TRANSITION; SCANNING TUNNELING MICROSCOPY; RECONSTRUCTED AU(111) SURFACE; 100 CRYSTAL FACES; ELECTRON-MICROSCOPY; PHASE-TRANSITION; GOLD; PLATINUM; IRIDIUM; DISLOCATIONS AB We present molecular-dynamics studies of structural transformations on metallic fcc(111) surfaces as a function of surface misfit and temperature. The particles interact through modified Lennard-Jones potentials. The studies focus on how the characteristic features of the surface-surface interatomic potential, specifically its repulsive core, determine the variation of surface misfit with temperature, and the stability of the ensuing structural phases and the nature of the observed phase transitions. The low-temperature phase consists of a striped phase of double-sine-Gordon domain walls oriented along one of the three equivalent [110] directions and stacked along the [112] direction. The temperature evolution of this phase was followed for two typical and distinct systems: in one system (system 1), the surface-surface potential was chosen so as to make the effective surface misfit decrease with temperature, while in the other (system II), the misfit increased or remained constant with temperature. System I undergoes an incommensurate-commensurate phase transition which appears to be second order in nature while system II exhibits an incommensurate-incommensurate phase transition. The temperature evolution of system II closely parallels the behavior of the Au(111) surface with rise in temperature. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. BOSTON UNIV,DEPT PHYS,BOSTON,MA 02215. NR 37 TC 5 Z9 5 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 MAY 15 PY 1993 VL 47 IS 19 BP 12771 EP 12784 DI 10.1103/PhysRevB.47.12771 PG 14 WC Physics, Condensed Matter SC Physics GA LE966 UT WOS:A1993LE96600044 ER PT J AU FARTASH, A GRIMSDITCH, M FULLERTON, EE SCHULLER, IK AF FARTASH, A GRIMSDITCH, M FULLERTON, EE SCHULLER, IK TI BREAKDOWN OF POISSON EFFECT IN NB/CU SUPERLATTICES SO PHYSICAL REVIEW B LA English DT Article ID COMPOSITION-MODULATED ALLOYS; X-RAY-SCATTERING; METALLIC SUPERLATTICES; SUPER-LATTICES; ELECTRONIC-STRUCTURE; ELASTIC-CONSTANTS; SURFACE-STRESS; THIN-FILMS; MULTILAYERS; BEHAVIOR AB The individual lattice spacings in Nb/Cu superlattices are determined from a crystallographic study using transmission and reflection x-ray diffraction. The Cu layers show a small in-plane expansion which increases to 0.6+/-0.1% as the modulation wavelength is reduced to 22 angstrom. Arguments based solely on Poisson's effect predict that the strains perpendicular to the layers must be smaller and of opposite sign; contrary to this expectation a large perpendicular expansion (4.2+/-0.7%) is measured. This finding brings into question the validity of models that rely only on interfacial forces to derive the perpendicular strains by using the bulk Poisson's ratio. C1 UNIV CALIF SAN DIEGO,DEPT PHYS 0319,LA JOLLA,CA 92093. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RI Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 43 TC 20 Z9 21 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 MAY 15 PY 1993 VL 47 IS 19 BP 12813 EP 12819 DI 10.1103/PhysRevB.47.12813 PG 7 WC Physics, Condensed Matter SC Physics GA LE966 UT WOS:A1993LE96600048 ER PT J AU KIM, HK YOU, H CHIARELLO, RP CHANG, HLM ZHANG, TJ LAM, DJ AF KIM, HK YOU, H CHIARELLO, RP CHANG, HLM ZHANG, TJ LAM, DJ TI FINITE-SIZE EFFECT ON THE 1ST-ORDER METAL-INSULATOR-TRANSITION IN VO2 FILMS GROWN BY METAL-ORGANIC CHEMICAL-VAPOR-DEPOSITION SO PHYSICAL REVIEW B LA English DT Article ID PHASE-TRANSITIONS; OPTICAL-PROPERTIES; VANADIUM DIOXIDE; THIN-FILMS; TEMPERATURE; STOICHIOMETRY; RUTILE AB We studied the finite-size effect on the first-order metal-insulator phase transition and the accompanying tetragonal-to-monoclinic structural transition of VO2 films. The VO2 films were epitaxially grown by a metal-organic chemical-vapor-deposition technique on the (101) growth plane of a 125-angstrom-thick TiO2 buffer layer which was also epitaxially predeposited on polished sapphire (1120BAR) substrates. The thickness of the VO2 films in this study ranges from 60 to 310 angstrom. We find that VO2 films grow isomorphically on the TiO2 buffer layer resulting in a high degree of epitaxial VO2 films. We determined structural correlation lengths of the VO2 films parallel and normal to the growth plane from the x-ray-diffraction widths of VO2 reflections at room temperature. The structural order parameter associated with the monoclinic distortion and the change in resistivity associated with the metal-insulator phase transition were simultaneously measured using x-ray-diffraction and resistivity measurements. It was found that the transition temperature, width of the transition, and the estimated electronic gap are dependent on the structural correlation length normal to the growth plane. These dependences are discussed in terms of finite-size and substrate effects on the first-order phase transition. C1 PUSAN NATL UNIV,DEPT PHYS,PUSAN,SOUTH KOREA. RP KIM, HK (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI You, Hoydoo/A-6201-2011; Kim, Hyung-Kook/J-2065-2012 OI You, Hoydoo/0000-0003-2996-9483; Kim, Hyung-Kook/0000-0003-4974-5233 NR 51 TC 60 Z9 60 U1 1 U2 22 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1993 VL 47 IS 19 BP 12900 EP 12907 DI 10.1103/PhysRevB.47.12900 PG 8 WC Physics, Condensed Matter SC Physics GA LE966 UT WOS:A1993LE96600057 ER PT J AU CHAMBERS, SA TRAN, TT AF CHAMBERS, SA TRAN, TT TI GEOMETRIC STRUCTURE AT THE SI/GAAS(001) INTERFACE - THE RELATIONSHIP TO ALAS/SI/GAAS BAND OFFSETS SO PHYSICAL REVIEW B LA English DT Note ID RAY PHOTOELECTRON DIFFRACTION AB We have used high-energy x-ray photoelectron diffraction to investigate the structure of the first monolayer of epitaxial Si on GaAs(001)-(2 X 4). Analysis reveals that Si indiffusion occurs, resulting in Si occupancies of approximately 0.6, 0.3, and 0.1 in the first, second, and third layers, respectively. In addition, Si atoms are displaced from their respective bulk truncated coordinates by 0.5+/-0.1 angstrom along [110] in the first layer, and by 0.4+/-0.1 angstrom along [110BAR] in the second layer. These results provide an explanation for the unusual band-offset behavior at AlAs/Si/GaAs heterojunctions. RP CHAMBERS, SA (reprint author), PACIFIC NW LAB, POB 999, MS K2-12, RICHLAND, WA 99352 USA. NR 11 TC 10 Z9 10 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1993 VL 47 IS 19 BP 13023 EP 13026 DI 10.1103/PhysRevB.47.13023 PG 4 WC Physics, Condensed Matter SC Physics GA LE966 UT WOS:A1993LE96600087 ER PT J AU MCGURN, AR CHRISTENSEN, KT MUELLER, FM MARADUDIN, AA AF MCGURN, AR CHRISTENSEN, KT MUELLER, FM MARADUDIN, AA TI ANDERSON LOCALIZATION IN ONE-DIMENSIONAL RANDOMLY DISORDERED OPTICAL-SYSTEMS THAT ARE PERIODIC ON AVERAGE SO PHYSICAL REVIEW B LA English DT Article AB We compute the frequency dependence of the localization length in a one-dimensional randomly disordered optical system, which on average is periodic, by studying the dependence of the transmissivity on the length of a finite random sample. Specifically, we consider a layered system of dielectric slabs with electromagnetic waves propagating perpendicular to the interfaces and compute the localization length for frequencies of these waves in and around the neighborhood of the band gaps in the photonic band structure of the average periodic system. The localization length is found to be very small in the gaps and much larger in the bands. We also compute the dependence of the localization length in the presence of dissipation (complex dielectric constant) and obtain a simple relationship, for frequencies of the electromagnetic waves in the allowed bands, between the localization length in the nondissipative system, the decay length in the nonrandom periodic system with dissipative terms, and the localization length in the presence of dissipation. For frequencies in the gaps the localization length appears to be insensitive to the presence of dissipation. C1 LOS ALAMOS NATL LAB,CTR MAT SCI,LOS ALAMOS,NM 87544. UNIV CALIF IRVINE,DEPT PHYS,IRVINE,CA 92717. RP MCGURN, AR (reprint author), WESTERN MICHIGAN UNIV,DEPT PHYS,KALAMAZOO,MI 49008, USA. RI Christensen, Kenneth/B-1123-2009 OI Christensen, Kenneth/0000-0003-1468-2455 NR 6 TC 116 Z9 121 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 MAY 15 PY 1993 VL 47 IS 20 BP 13120 EP 13125 DI 10.1103/PhysRevB.47.13120 PG 6 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900003 ER PT J AU BONCA, J GUBERNATIS, JE AF BONCA, J GUBERNATIS, JE TI QUANTUM MONTE-CARLO SIMULATIONS OF THE DEGENERATE SINGLE-IMPURITY ANDERSON MODEL SO PHYSICAL REVIEW B LA English DT Article ID DILUTE MAGNETIC-ALLOYS; RENORMALIZATION-GROUP APPROACH; LARGE-N EXPANSION; STATIC PROPERTIES; MAXIMUM-ENTROPY; DYNAMICS; METALS; CE AB We present results of quantum Monte Carlo simulations of the degenerate, single-impurity, Anderson model. Using maximum-entropy methods, we performed the analytic continuation of the imaginary-time Green's functions produced by these simulations to obtain their real-frequency, single-particle, spectral densities for degeneracies of N = 2, 4, and 6. Incorporating higher degeneracies into the model enables us, on the one hand, to compare Monte Carlo results with the self-consistent large-N approximation (NCA) and numerical-renormalization-group calculations (NGR) and, on the other hand, to bring the models closer to the physical systems. The low temperatures reached in our calculations are comparable to, or even lower than, the corresponding Kondo temperatures. The NCA and NRG calculations were found to show qualitatively good agreement with our results: the Kondo temperature increases with increasing degeneracy, and the amplitude of the side peaks in the spectral density decreases as degeneracy increases while the half-width of these peaks increases. C1 LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP BONCA, J (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 27 TC 14 Z9 14 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1993 VL 47 IS 20 BP 13137 EP 13146 DI 10.1103/PhysRevB.47.13137 PG 10 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900005 ER PT J AU LORENZANA, J GRYNBERG, MD YU, L YONEMITSU, K BISHOP, AR AF LORENZANA, J GRYNBERG, MD YU, L YONEMITSU, K BISHOP, AR TI DYNAMIC AND STATIC CORRELATION-FUNCTIONS IN THE INHOMOGENEOUS-HARTREE-FOCK-STATE APPROACH WITH RANDOM-PHASE-APPROXIMATION FLUCTUATIONS SO PHYSICAL REVIEW B LA English DT Article ID HUBBARD-MODEL; SUPERCONDUCTORS AB The ground-state energy and static and dynamic correlation functions are investigated in the inhomogeneous-Hartree-Fock (IHF) plus random-phase-approximation (RPA) approach applied to a one-dimensional spinless-fermion model showing self-trapped doping states at the mean-field level. Results are compared with those obtained using homogeneous HF and exact diagonalization. RPA fluctuations added to the generally inhomogeneous-HF ground state allow the computation of dynamical correlation functions that compare well with exact diagonalization results. The RPA correction to the ground-state energy agrees well with the exact results at strong- and weak-coupling limits. We also compare it with a related quasiboson approach. The instability towards self-trapped behavior is signaled by a RPA mode with frequency approaching zero. C1 INT CTR THEORET PHYS,I-34014 TRIESTE,ITALY. LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP LORENZANA, J (reprint author), SCUOLA INT SUPER STUDI AVANZATI,VIA BEIRUT 4,I-34014 TRIESTE,ITALY. RI Lorenzana, Jose/A-2809-2008; OI Lorenzana, Jose/0000-0001-7426-2570; Grynberg, Marcelo/0000-0002-1111-3954 NR 22 TC 9 Z9 9 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1993 VL 47 IS 20 BP 13156 EP 13163 DI 10.1103/PhysRevB.47.13156 PG 8 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900008 ER PT J AU MYERS, SM FOLLSTAEDT, DM STEIN, HJ WAMPLER, WR AF MYERS, SM FOLLSTAEDT, DM STEIN, HJ WAMPLER, WR TI HYDROGEN INTERACTIONS WITH CAVITIES IN HELIUM-IMPLANTED SILICON SO PHYSICAL REVIEW B LA English DT Article ID SI-SIO2 INTERFACE DEFECTS; DESORPTION-KINETICS; SI(111)-7X7 SURFACE; ATOMIC-HYDROGEN; ION-BEAM; DIFFUSION; SI(100); SPECTROSCOPY; MONOHYDRIDE; ADSORPTION AB Hydrogen interactions with microscopic cavities in Si were quantitatively characterized in thermal-release experiments. Closed internal cavities were formed by He-ion implantation and annealing and were characterized by transmission-electron microscopy. The isotopes protium (H-1) and deuterium (D) were introduced by ion implantation or heating in H-2 gas. During temperature ramping the redistribution and release of D were monitored by nuclear-reaction profiling, and the bonding of H-1 was selectively examined by infrared absorption spectroscopy. By exploiting the properties of closed internal surfaces this study determined the Si-H bond energy for surface monohydrides, the result being 2.5 +/- 0.2 eV. Hydrogen bonded to the internal surfaces was found to lie several tenths of an eV lower in energy than H-2 gas and H trapped at lattice defects. The oxidized external surface of the Si specimens did not detectably impede H release, implying an efficient recombination process at the Si-SiO2 interface for which possible mechanisms are considered. RP MYERS, SM (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 48 TC 49 Z9 49 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 MAY 15 PY 1993 VL 47 IS 20 BP 13380 EP 13394 DI 10.1103/PhysRevB.47.13380 PG 15 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900035 ER PT J AU MA, X KOURI, DJ LUBAN, M NAYAR, N HOFFMAN, DK AF MA, X KOURI, DJ LUBAN, M NAYAR, N HOFFMAN, DK TI ELASTIC ELECTRON TRANSMISSION BY BARRIERS IN A 3-DIMENSIONAL MODEL QUANTUM-WIRE SO PHYSICAL REVIEW B LA English DT Article ID DEPENDENT SCHRODINGER-EQUATION; MOLECULE SURFACE SCATTERING; FOURIER METHOD SOLUTION; WAVE; TRANSPORT; DYNAMICS; STATES AB Numerical solutions of the time-dependent and time-independent Schrodinger equations for electron tunneling in a three-dimensional model quantum wire have been carried out and used to calculate transmission probabilities over a range of energies. The model simulates a quantum heterostructure corresponding to a cylindrically symetric wire constructed from two different materials such that square barriers to the axial (z) motion occur in the disjoint region B=(z1 less-than-or-equal-to z less-than-or-equal-to z2) or (z3 less-than-or-equal-to z less-than-or-equal-to z4). In addition, the electron is bound harmonically in the radial distance r transverse to the longitudinal axis z; the electron vibrational frequency changes discontinuously from omega(A) in the disjoint region A = ( - infinity < Z < Z1) or (z2 < Z < Z3) or (Z4 < Z < infinity) to omega(B) in the disjoint region B. A basis-set expansion, using harmonic-oscillator eigenstates appropriate to regions A or B, for the electron's radial vibration transverse to the cylinder axis is used. The basis-set expansion using the eigenstates of the electrons rotation about z only involved the ground rotational state since, due to cylindrical symmetry, the electron does not experience any torques. This ''close-coupling expansion'' procedure yields close-coupled-wave-packet (CCWP) equations for the time-dependent expansion coefficients in the time-dependent approach, and a system of linear algebraic equations for the expansion coefficients in the time-independent approach. The change of electronic vibration frequency from region A to region B leads to nonadiabatic transitions, giving rise to transmission amplitudes that depend on the final electron-vibrational state. The model is elastic in that phonon degrees of freedom are not included. A final-state analysis for the time-dependent CCWP method is given which does not require spatial integrals of the wave packets. This enables results over a broad energy range (including resonant energies) to be acquired from a single wave-packet propagation, because the packet is initially taken to be relatively narrow in coordinate space. The method is extremely stable over the whole range of energies. All calculations used an initial state comprised of the ground vibrational and zero angular momentum wave functions and vibrationally resolved transmission probabilities are studied for various frequency ratios omega(A)/omega(B) and as a function of total energy. Vibrational nonadiabaticity is found to depend strongly of the frequency ratio, and on collision energy. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. RP MA, X (reprint author), UNIV HOUSTON,DEPT CHEM,HOUSTON,TX 77204, USA. NR 33 TC 0 Z9 0 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 MAY 15 PY 1993 VL 47 IS 20 BP 13508 EP 13519 DI 10.1103/PhysRevB.47.13508 PG 12 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900050 ER PT J AU HUANG, ZQ WANG, LQ VONWITTENAU, AES HUSSAIN, Z SHIRLEY, DA AF HUANG, ZQ WANG, LQ VONWITTENAU, AES HUSSAIN, Z SHIRLEY, DA TI ANGLE-RESOLVED PHOTOEMISSION EXTENDED FINE-STRUCTURE STUDY OF THE STRUCTURE OF P(2X2)K/NI(111) SO PHYSICAL REVIEW B LA English DT Article ID METAL-SURFACES; STRUCTURE SPECTROSCOPY; ELECTRONIC-STRUCTURE; ADSORPTION; TRANSITION; GEOMETRY AB Angle-resolved photoemission extended fine structure (ARPEFS) from the potassium Is core level was measured for the quantitative structural determination of the p (2 X 2)K/Ni(111) overlayer at 130 K. Our analysis of the ARPEFS chi(k) curves detected along [111] and [771] showed that the potassium atoms are preferentially adsorbed on the atop sites, in agreement with a previous low-energy-electron-diffraction (LEED) study of the same system. The K-Ni bond length is 3.02 +/- 0.01 angstrom, yielding an effective hard-sphere radius of 1.77 angstrom for potassium. The first-to-second-layer spacing of nickel is 1.90 +/- 0.04 angstrom, a 6.5% contraction from the bulk spacing of 2.03 angstrom. Furthermore, the first nickel layer shows neither lateral reconstruction (0.00 +/- 0.09 angstrom) nor vertical corrugation (0.00 +/- 0.03 angstrom). A comparison of the structural parameters with those determined from the LEED study is presented. The limitations of Fourier analysis for site determination and the importance of comparing ARPEFS experimental data with theoretical simulations in both k space and r space are also discussed. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720. PENN STATE UNIV,DEPT CHEM,UNIV PK,PA 16802. PENN STATE UNIV,DEPT PHYS,UNIV PK,PA 16802. NR 34 TC 25 Z9 26 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1993 VL 47 IS 20 BP 13626 EP 13635 DI 10.1103/PhysRevB.47.13626 PG 10 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900065 ER PT J AU FERNANDO, GW MEI, J WATSON, RE WEINERT, M DAVENPORT, JW AF FERNANDO, GW MEI, J WATSON, RE WEINERT, M DAVENPORT, JW TI CU-PD MULTILAYERS - AN ATOMISTIC STRUCTURAL STUDY SO PHYSICAL REVIEW B LA English DT Article ID EMBEDDED-ATOM METHOD; MOLECULAR-DYNAMICS; METALLIC SUPERLATTICES; ELECTRONIC-STRUCTURE; ORBITAL METHOD; THIN-FILMS; FCC METALS; POTENTIALS; MODULUS; COPPER AB The embedded-atom method (EAM) has been used to perform molecular-dynamics (MD) calculations of Cu/Pd multilayer films. In a recent publication, we presented our results on the elastic properties of these multilayers from our EAM-MD technique. In this paper we illustrate the simulation technique in detail. Comparisons are made with first-principles (local-density) calculations with respect to structural aspects of the multilayer. The local-density results follow trends similar to those seen in the EAM-MD approach. Various assumptions used in these calculations are critically examined. C1 UNIV CONNECTICUT,DEPT PHYS,STORRS,CT 06269. SUNY,DEPT PHYS,STONY BROOK,NY 11794. RP FERNANDO, GW (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 26 TC 11 Z9 11 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1993 VL 47 IS 20 BP 13636 EP 13642 DI 10.1103/PhysRevB.47.13636 PG 7 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900066 ER PT J AU CHRISTENSEN, OB COHEN, ML AF CHRISTENSEN, OB COHEN, ML TI GROUND-STATE PROPERTIES OF SMALL IRON CLUSTERS SO PHYSICAL REVIEW B LA English DT Article ID ABINITIO MOLECULAR-DYNAMICS; ELECTRONIC SHELL STRUCTURE; ALKALI-METAL CLUSTERS; SODIUM CLUSTERS; SPIN RELAXATION; SURFACES; MICROCLUSTERS; TEMPERATURES; CU(110) AB Ground-state structures of small iron clusters, N less-than-or-equal-to 18, are determined from simulated-annealing calculations. Total energies are calculated using the effective-medium theory, and the d-band energy is included using the tight-binding approximation. The main effects of the partially filled d band are a higher symmetry of the ground-state structures than those assumed by simple metals such as Na and Cu and a tendency to produce hollow structures. We find a correlation between the presence of unscreened atoms in the iron-cluster ground states and measured ionization potentials and reactivities with H-2. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RI Christensen, Ole/E-4417-2013 NR 30 TC 42 Z9 42 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1993 VL 47 IS 20 BP 13643 EP 13647 DI 10.1103/PhysRevB.47.13643 PG 5 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900067 ER PT J AU SPECHT, ED WALKER, FJ AF SPECHT, ED WALKER, FJ TI OXIDATION-STATE OF A BURIED INTERFACE - NEAR-EDGE X-RAY FINE-STRUCTURE OF A CRYSTAL TRUNCATION ROD SO PHYSICAL REVIEW B LA English DT Article ID ANOMALOUS SCATTERING FACTORS; DIFFRACTION; SURFACES AB We observe that the crystal-truncation-rod (CTR) diffraction from the Al2O3 substrate of an A12O3/Cr2O3(001) interface has fine structure when the x-ray energy is tuned through the Cr K absorption edge. This fine structure is attributed to interference between scattering from the substrate and Cr atoms at the interface, which are coherent with the substrate. Comparisons with x-ray-absorption spectra of standard samples demonstrate that the Cr at the interface is predominantly in the Cr3+ oxidation state. We demonstrate how the near-edge energy dependence of the CTR diffracted intensity may be used to deduce the amplitude and phase of the interface scattering. This phase information is used in conjunction with reciprocal-lattice-vector-dependent measurements of diffracted power due to CTR's to deduce the structure of the Cr2O3/Al2O3 interface. While the local atomic coordination at the interface is the same as that of Al2O3 and Cr2O3, there is a stacking fault at the interface covering half of the interface area. RP SPECHT, ED (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831, USA. RI Specht, Eliot/A-5654-2009; OI Specht, Eliot/0000-0002-3191-2163; Walker, Frederick/0000-0002-8094-249X NR 33 TC 18 Z9 18 U1 1 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1993 VL 47 IS 20 BP 13743 EP 13751 DI 10.1103/PhysRevB.47.13743 PG 9 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900081 ER PT J AU BARTELT, MC TRINGIDES, MC EVANS, JW AF BARTELT, MC TRINGIDES, MC EVANS, JW TI ISLAND-SIZE SCALING IN SURFACE DEPOSITION PROCESSES SO PHYSICAL REVIEW B LA English DT Note ID THIN-FILMS; PERCOLATION AB Diffusion-mediated nucleation and growth of islands during deposition occurs essentially irreversibly in a variety of systems. We provide a scaling theory for the full island-size distribution, both with the ratio of surface diffusion to deposition rates and with time. Scaling functions and exponents are determined by simulation and explained analytically by an unconventional rate-equation analysis. Experimental tests for theoretical predictions are discussed, including the scaling of superlattice beam profiles for diffraction studies of heteroepitaxial systems. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT MATH,AMES,IA 50011. RP BARTELT, MC (reprint author), IOWA STATE UNIV SCI & TECHNOL,INST PHYS RES & TECHNOL,AMES,IA 50011, USA. NR 15 TC 59 Z9 62 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 MAY 15 PY 1993 VL 47 IS 20 BP 13891 EP 13894 DI 10.1103/PhysRevB.47.13891 PG 4 WC Physics, Condensed Matter SC Physics GA LF069 UT WOS:A1993LF06900106 ER PT J AU BECKERSZENDY, R BRATTON, CB CASPER, D DYE, ST GAJEWSKI, W GOLDHABER, M HAINES, TJ HALVERSON, PG KIELCZEWSKA, D KROPP, WR LEARNED, JG LOSECCO, JM MATSUNO, S MCGRATH, G MCGREW, C MILLER, RS PRICE, L REINES, F SCHULTZ, J SOBEL, HW STONE, JL SULAK, LR SVOBODA, R AF BECKERSZENDY, R BRATTON, CB CASPER, D DYE, ST GAJEWSKI, W GOLDHABER, M HAINES, TJ HALVERSON, PG KIELCZEWSKA, D KROPP, WR LEARNED, JG LOSECCO, JM MATSUNO, S MCGRATH, G MCGREW, C MILLER, RS PRICE, L REINES, F SCHULTZ, J SOBEL, HW STONE, JL SULAK, LR SVOBODA, R TI STUDY OF UNDERGROUND MUONS DURING THE JANUARY 1991 RADIO FLARE OF CYGNUS-X-3 SO PHYSICAL REVIEW D LA English DT Article ID DIRECTION; SEARCH AB Muons recorded by the IMB proton decay detector during the radio outburst from Cygnus X-3 in January 1991 are studied. Data are examined for both aperiodic excesses and those phase modulated at the x-ray period of Cygnus X-3. No correlation between the muon data and Cygnus X-3 is found. Further, this observation provides flux limits of PHI90% C.L. less-than-or-equal-to 2 x 10(-10) mu cm-2s-1 at 1570 meters of water equivalent on the 20th and 23rd, in contrast with other reported signals. C1 UNIV NOTRE DAME,NOTRE DAME,IN 46556. UNIV WARSAW,PL-00325 WARSAW,POLAND. UNIV CALIF IRVINE,IRVINE,CA 92717. BROOKHAVEN NATL LAB,UPTON,NY 11973. BOSTON UNIV,BOSTON,MA 02215. CLEVELAND STATE UNIV,CLEVELAND,OH 44115. UNIV HAWAII,HONOLULU,HI 96822. LOUISIANA STATE UNIV,BATON ROUGE,LA 70803. UNIV MARYLAND,COLL PK,MD 20742. UNIV NOTRE DAME,NOTRE DAME,IN 46556. UNIV WARSAW,PL-00325 WARSAW,POLAND. RI Sobel, Henry/A-4369-2011 NR 16 TC 1 Z9 1 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 15 PY 1993 VL 47 IS 10 BP 4203 EP 4205 DI 10.1103/PhysRevD.47.4203 PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LE326 UT WOS:A1993LE32600006 ER PT J AU FIELDS, BD DODELSON, S TURNER, MS AF FIELDS, BD DODELSON, S TURNER, MS TI EFFECT OF NEUTRINO HEATING ON PRIMORDIAL NUCLEOSYNTHESIS SO PHYSICAL REVIEW D LA English DT Article ID LITHIUM ABUNDANCE; EARLY UNIVERSE; DWARFS; STARS; HE-3 AB We modify the standard code for primordial nucleosynthesis to include the effect of the slight heating of neutrinos by e+/- annihilations. There is a small, systematic change in the He-4 yield, DELTAY congruent-to +1.5X10(-4), which is insensitive to the value of the baryon-to-photon ratio eta for 10(-10) less than or similar to eta less than or similar to 10(-9). We also find that the baryon-to-photon ratio decreases by about 0.5% less than the canonical factor of 4/11 because some of the entropy in e+/- pairs is transferred to neutrinos. These results are in accord with recent analytical estimates. C1 FERMILAB NATL ACCELERATOR LAB,NASA FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. UNIV CHICAGO,ENRICO FERMI INST,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637. RP FIELDS, BD (reprint author), UNIV CHICAGO,DEPT PHYS,CHICAGO,IL 60637, USA. NR 26 TC 36 Z9 36 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 15 PY 1993 VL 47 IS 10 BP 4309 EP 4314 DI 10.1103/PhysRevD.47.4309 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LE326 UT WOS:A1993LE32600022 ER PT J AU BENMENAHEM, S AF BENMENAHEM, S TI SELF-GRAVITATING STRINGS IN 2+1 DIMENSIONS SO PHYSICAL REVIEW D LA English DT Article ID GENERAL-RELATIVITY; SPACE-TIME; MODEL AB We present a family of classical spacetimes in 2+1 dimensions. Such a spacetime is produced by a Nambu-Goto self-gravitating string. Because of the special properties of three-dimensional gravity, the metric is completely described as a Minkowski space with two identified world sheets. In the flat limit, the standard string is recovered. The formalism is developed for an open string with massive end points, but applies to other boundary conditions as well. We consider another limit, where the string tension vanishes in geometrical units but the end masses produce finite deficit angles. In this limit, our open string reduces to the free-masses solution of Gott, which possesses closed timelike curves when the relative motion of the two masses is sufficiently rapid. It is shown that the induced world sheet Liouville mode obeys (classically) a sinh- or cosh-Gordon differential equation, which reduces to the Liouville equation in the fiat limit. A quadratic-action formulation of this system is presented. The possibility and significance of quantizing the self-gravitating string is discussed. RP BENMENAHEM, S (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,POB 4349,STANFORD,CA 94305, USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 15 PY 1993 VL 47 IS 10 BP 4344 EP 4361 DI 10.1103/PhysRevD.47.4344 PG 18 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LE326 UT WOS:A1993LE32600027 ER PT J AU KOSOWSKY, A TURNER, MS AF KOSOWSKY, A TURNER, MS TI GRAVITATIONAL-RADIATION FROM COLLIDING VACUUM BUBBLES - ENVELOPE APPROXIMATION TO MANY-BUBBLE COLLISIONS SO PHYSICAL REVIEW D LA English DT Article ID EXTENDED INFLATION; PHASE-TRANSITIONS; EARLY UNIVERSE; FALSE VACUUM; STRINGS; FATE AB We introduce an approximation to calculate the gravitational radiation produced by the collision of true-vacuum bubbles that is simple enough to allow the simulation of a phase transition by the collision of hundreds of bubbles. This ''envelope approximation'' neglects the complicated ''overlap'' regions of colliding bubbles and follows only the evolution of the bubble walls. The approximation accurately reproduces previous results for the gravitational radiation from the collision of two scalar-field vacuum bubbles. Using a bubble nucleation rate given by GAMMA = GAMMA0e(betat), we simulate a phase transition by colliding 20 to 200 bubbles; the fraction of vacuum energy released into gravity waves is E(GW)/E(vac) = 0.06(H/beta)2 and the peak of the spectrum occurs at omega(max) = 1.6beta(H2 = 8piGrho/3 is the Hubble constant associated with the false-vacuum phase). The spectrum is very similar to that in the two-bubble case, except that the efficiency of gravity-wave generation is about five times higher, presumably due to the fact that a given bubble collides with many others. Finally, we consider two further ''statistical'' approximations, where the gravitational radiation is computed as an incoherent sum over individual bubbles weighted by the distribution of bubble sizes. These approximations provide reasonable estimates of the gravitational-wave spectrum with far less computation. C1 FERMILAB NATL ACCELERATOR LAB,NASA FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. RP KOSOWSKY, A (reprint author), UNIV CHICAGO,ENRICO FERMI INST,DEPT PHYS,CHICAGO,IL 60637, USA. NR 38 TC 105 Z9 105 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 15 PY 1993 VL 47 IS 10 BP 4372 EP 4391 DI 10.1103/PhysRevD.47.4372 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LE326 UT WOS:A1993LE32600029 ER PT J AU PAPAVASSILIOU, J AF PAPAVASSILIOU, J TI GAUGE-INVARIANT 4-GLUON VERTEX AND ITS WARD IDENTITY SO PHYSICAL REVIEW D LA English DT Article ID QCD AB We use the S-matrix pinch technique to construct at one-loop order a four-gluon vertex for QCD, which is independent of the choice of the gauge parameter, when one or more of the incoming momenta are off shell. We discuss some of the technical subtleties in the application of the pinch technique and show that this vertex satisfies a very simple Ward identity, relating it to a previously constructed gauge-independent three-gluon vertex, also found with the same technique. This analysis serves as a prelude to the construction of an effective potential for QCD, which is gauge-independent order by order in the dressed-loop expansion. RP BROOKHAVEN NATL LAB, DEPT PHYS, UPTON, NY 11973 USA. RI Papavassiliou, Joannis/K-3973-2014 OI Papavassiliou, Joannis/0000-0003-3958-8174 NR 17 TC 40 Z9 40 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD MAY 15 PY 1993 VL 47 IS 10 BP 4728 EP 4738 DI 10.1103/PhysRevD.47.4728 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LE326 UT WOS:A1993LE32600065 ER PT J AU RAJEEVAN, MS LANG, A AF RAJEEVAN, MS LANG, A TI FLOWER-BUD FORMATION IN EXPLANTS OF PHOTOPERIODIC AND DAY-NEUTRAL NICOTIANA BIOTYPES AND ITS BEARING ON THE REGULATION OF FLOWER FORMATION SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE PHOTOPERIODISM IN PLANTS; PLANT TISSUE CULTURE ID FLORAL DETERMINATION; TABACUM-L; TOBACCO; CULTURES; TISSUE AB The capacity to form flower buds in thin-layer explants was studied in flowering plants of several species, cultivars, and lines of Nicotiana differing in their response to photoperiod. This capacity was found in all biotypes examined and could extend into sepals and corolla. It varied greatly, depending on genotype, source tissue and its developmental stage, and composition of the culture medium, particularly the levels of glucose, auxin, and cytokinin. It was greatest in the two day-neutral plants examined, Samsun tobacco and Nicotiana rustica, where it extended from the inflorescence region down the vegetative stem, in a basipetally decreasing gradient; it was least in the two qualitative photoperiodic plants studied, the long-day plant Nicotiana silvestris and the short-day plant Maryland Mammoth tobacco, the quantitative long-day plant Nicotiana alata and the quantitative short-day plant Nicotiana otophora line 38-G-81, where it was limited to the pedicels (and, in some cases, the sepals). Regardless of the photoperiodic response of the source plants, the response was the same in explants cultured under long and short days. The finding that capacity to form flower buds in explants is present in all Nicotiana biotypes studied supports the idea that it is regulated by the same mechanism(s), regardless of the plant's photoperiodic character. However, the source plants were all in the flowering stage, and no flower-bud formation can be obtained in explants from strictly vegetative Nicotiana plants. Hence, flower formation in the explants is not identical with de novo flower formation in a hitherto vegetative plant: it is rather the expression of a floral state already established in the plant, although it can vary widely in extent and spatial distribution. Culture conditions that permit flower-bud formation in an explant are conditions that maintain the floral state and encourage its expression; conditions under which no flower buds are formed reduce this state and/or prevent its expression. C1 MICHIGAN STATE UNIV,MSU DOE,PLANT RES LAB,E LANSING,MI 48824. NR 14 TC 8 Z9 8 U1 0 U2 1 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD MAY 15 PY 1993 VL 90 IS 10 BP 4636 EP 4640 DI 10.1073/pnas.90.10.4636 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA LC720 UT WOS:A1993LC72000066 PM 11607381 ER PT J AU MCKAMEY, CG PIERCE, DH AF MCKAMEY, CG PIERCE, DH TI EFFECT OF RECRYSTALLIZATION ON ROOM-TEMPERATURE TENSILE PROPERTIES OF AN FE3AL-BASED ALLOY SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article ID HYDROGEN EMBRITTLEMENT; FEAL RP MCKAMEY, CG (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831, USA. NR 18 TC 61 Z9 61 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0956-716X J9 SCRIPTA METALL MATER JI Scr. Metall. Materialia PD MAY 15 PY 1993 VL 28 IS 10 BP 1173 EP 1176 DI 10.1016/0956-716X(93)90449-3 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA KW621 UT WOS:A1993KW62100001 ER PT J AU BARTGES, CW LIN, JS AF BARTGES, CW LIN, JS TI EFFECT OF SN ADDITIONS ON GP ZONE FORMATION IN AL-CU ALLOYS SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article ID ANGLE X-RAY; SCATTERING C1 OAK RIDGE NATL LAB,DIV SOLID STATE,CTR SMALL ANGLE SCATTERING RES,OAK RIDGE,TN 37831. RP BARTGES, CW (reprint author), ALCOA,ALCOA TECH CTR,ALCOA CTR,PA 15069, USA. NR 16 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 0956-716X J9 SCRIPTA METALL MATER JI Scr. Metall. Materialia PD MAY 15 PY 1993 VL 28 IS 10 BP 1283 EP 1286 DI 10.1016/0956-716X(93)90469-9 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA KW621 UT WOS:A1993KW62100021 ER PT J AU WRIGHT, RN ERICKSON, AE OBRIEN, MH RABIN, BH AF WRIGHT, RN ERICKSON, AE OBRIEN, MH RABIN, BH TI CHARACTERIZATION OF AL2TI PRECIPITATES IN CUBIC AL64.5TI27.5CR8 SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article ID STRUCTURAL L12 COMPOUNDS; ALLOYING AL3TI; PLASTIC-DEFORMATION; CR; MN; BEHAVIOR RP WRIGHT, RN (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415, USA. NR 18 TC 5 Z9 5 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0956-716X J9 SCRIPTA METALL MATER JI Scr. Metall. Materialia PD MAY 15 PY 1993 VL 28 IS 10 BP 1293 EP 1297 DI 10.1016/0956-716X(93)90471-4 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA KW621 UT WOS:A1993KW62100023 ER PT J AU FRANK, HA FARHOOSH, R GEBHARD, R LUGTENBURG, J GOSZTOLA, D WASIELEWSKI, MR AF FRANK, HA FARHOOSH, R GEBHARD, R LUGTENBURG, J GOSZTOLA, D WASIELEWSKI, MR TI THE DYNAMICS OF THE S1 EXCITED-STATES OF CAROTENOIDS SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ENERGY-TRANSFER AB Transient absorption spectroscopy was used to measure the S1 dynamics of four all-trans-carotenoids: 3,4,7,8-tetrahydrospheroidene, 3,4,5,6-tetrahydrospheroidene, 3,4-dihydrospheroidene and spheroidene. After excitation into the S2 state and subsequent relaxation to the S1 state, the S1-->S(n) electronic absorption bands in the region 460-520 nm were probed and observed to decay with single-exponential kinetics: tau = 407 +/- 23 ps for 3,4,7,8-tetrahydrospheroidene, 85 +/- 5 ps for 3,4,5,6-tetrahydrospheroidene, 25.4 +/- 0.9 ps for 3,4-dihydrospheroidene and 8.7 +/- 0.1 ps for spheroidene. These data are discussed in three contexts: (1) as a test of the adherence of carotenoids to the energy gap law; (2) as a means of determining the S1 state energy of spheroidene, which appears to be at 14100 cm-1; and (3) in terms of the constraints placed on the efficiencies of carotenoid-to-chlorophyll energy transfer in photosynthetic systems. C1 LEIDEN UNIV, GORLAEUS LABS, 2300 RA LEIDEN, NETHERLANDS. ARGONNE NATL LAB, DIV CHEM, ARGONNE, IL 60439 USA. RP FRANK, HA (reprint author), UNIV CONNECTICUT, DEPT CHEM, STORRS, CT 06269 USA. RI Gosztola, David/D-9320-2011 OI Gosztola, David/0000-0003-2674-1379 NR 15 TC 55 Z9 55 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 EI 1873-4448 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD MAY 14 PY 1993 VL 207 IS 1 BP 88 EP 92 DI 10.1016/0009-2614(93)85016-H PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LB949 UT WOS:A1993LB94900016 ER PT J AU LOTT, JA SCHNEIDER, RP AF LOTT, JA SCHNEIDER, RP TI ELECTRICALLY INJECTED VISIBLE (639-661 NM) VERTICAL-CAVITY SURFACE-EMITTING LASERS SO ELECTRONICS LETTERS LA English DT Article DE LASERS; SEMICONDUCTOR LASERS AB The first electrically injected visible InAlGaP/AlGaAs vertical cavity surface emitting lasers am reported. The devices consist of an InAlGaP optical cavity active region surrounded by AlAs/AlGaAs distributed Bragg reflectors. Pulsed room temperature lasing has been observed at wavelengths from 639 to 661 nm. At 650 nm, thresholds of 30 mA at 2.7 V were measured on test devices with a 20 mum emission diameter. Peak output power exceeds 3.3 mW. RP LOTT, JA (reprint author), SANDIA NATL LABS,COMPOUND SEMICOND RES LAB,ALBUQUERQUE,NM 87185, USA. NR 7 TC 28 Z9 28 U1 0 U2 4 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD, ENGLAND SG1 2AY SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD MAY 13 PY 1993 VL 29 IS 10 BP 830 EP 832 DI 10.1049/el:19930555 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA LN177 UT WOS:A1993LN17700002 ER PT J AU HOFFMAN, DK KOURI, DJ AF HOFFMAN, DK KOURI, DJ TI DISTRIBUTED APPROXIMATING FUNCTION-THEORY FOR AN ARBITRARY NUMBER OF PARTICLES IN A COORDINATE SYSTEM-INDEPENDENT FORMALISM SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article AB A general, multidimensional distributed approximating function theory is developed that applies to any system which has one possible configurational representation in Cartesian variables. That is, the configuration of the system can be expressed as a generalized N-dimensional vector which has the usual transformation properties under multidimensional rotations. In particular, the theory is applicable to a scattering system with an arbitrary number, A, of scattering centers and projectiles (atoms), for which N = 3A. The approach makes possible the realization of distributed approximating functions (DAFs) in any orthogonal, curvilinear coordinates including spherical polar, cylindrical polar, and hyperspherical, as well as elliptic and parabolic coordinates. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. UNIV HOUSTON,DEPT CHEM,HOUSTON,TX 77204. UNIV HOUSTON,DEPT PHYS,HOUSTON,TX 77204. RP HOFFMAN, DK (reprint author), IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011, USA. NR 21 TC 18 Z9 18 U1 0 U2 0 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 MAY 13 PY 1993 VL 97 IS 19 BP 4984 EP 4988 DI 10.1021/j100121a021 PG 5 WC Chemistry, Physical SC Chemistry GA LB803 UT WOS:A1993LB80300021 ER PT J AU EVLETH, EM MELIUS, CF RAYEZ, MT RAYEZ, JC FORST, W AF EVLETH, EM MELIUS, CF RAYEZ, MT RAYEZ, JC FORST, W TI THEORETICAL CHARACTERIZATION OF THE REACTION OF HO2 WITH FORMALDEHYDE SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID FLASH-PHOTOLYSIS; MECHANISM; PHOTOOXIDATION; OXIDATION; KINETICS; MODEL AB The reaction of HO2+ formaldehyde is characterized at both the semiempirical and ab initio levels. It is shown that semiempirical methods do not furnish the information necessary to rationalize the kinetics of the formation of OOCH2OH. The mechanism of this reaction is rationalized at both the MP4/6-31G** and BAC MP4/6-31G** levels. The critical transition state for this reaction involves the simultaneous addition of the terminal oxygen atom of HO2 to the carbon of the CO bond and transfer of a proton from OOH to the oxygen of this same bond. It is shown that the previously proposed mechanism involving the intermediate formation of the HOOCH2O radical is incorrect. Kinetic modeling indicates that the critical transition state has an energy close to the incoming HO2 + CH2O channel and that a large deuterium isotope effect should occur in the reaction of DO2 + CH2O. C1 UNIV BORDEAUX,PHYSICOCHIM THEOR LAB,CNRS,UA503,F-33405 TALENCE,FRANCE. SANDIA NATL LABS,LIVERMORE,CA 94550. RP EVLETH, EM (reprint author), UNIV PARIS 06,DYNAM INTERACT MOLEC LAB,CNRS,ER 271,4 PL JUSSIEU,F-75230 PARIS 05,FRANCE. NR 20 TC 31 Z9 31 U1 0 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 MAY 13 PY 1993 VL 97 IS 19 BP 5040 EP 5045 DI 10.1021/j100121a031 PG 6 WC Chemistry, Physical SC Chemistry GA LB803 UT WOS:A1993LB80300031 ER PT J AU BERMAN, A HANSON, J LEISEROWITZ, L KOETZLE, TF WEINER, S ADDADI, L AF BERMAN, A HANSON, J LEISEROWITZ, L KOETZLE, TF WEINER, S ADDADI, L TI CRYSTAL PROTEIN INTERACTIONS - CONTROLLED ANISOTROPIC CHANGES IN CRYSTAL MICROTEXTURE SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID ORGANIC MATRIX; ASPARTIC-ACID; MACROMOLECULES; DIFFRACTION; CALCITE AB A unique set of proteins extracted from a variety of invertebrate calcitic mineralized tissues is able to selectively interact in vitro with certain crystal faces and not others. This was previously demonstrated by observing changes in morphology of crystals grown in the presence of proteins as compared to those grown in the absence of proteins. Following interaction, the proteins are overgrown by the crystal and are subsequently occluded within the crystal itself. Here we address the fundamental question of whether or not the proteins also alter the crystal texture in an anisotropic manner. For this purpose we used high-resolution synchrotron X-ray diffraction to monitor changes in coherence length and angular spread. We studied the interactions of proteins extracted from the mineralized skeletal hard parts of sea urchins and mollusks, with crystals of two calcium dicarboxylic acids, calcium fumarate and calcium malonate, as well as the polymorph of CaCO3 calcite. For the calcium dicarboxylate crystals, we did demonstrate that the coherence lengths are reduced in the directions perpendicular to the planes onto which the proteins preferentially adsorb. In contrast the calcite crystals grown in the presence of the proteins exhibited an increase in angular spread compared to the controls, but no anisotropic effect in coherence length was detected. A biologically produced calcite crystal, on the other hand, showed a preferential reduction in coherence length in the direction of the c axis. Clearly in the case of calcite, the processes controlling crystal texture in the biological environment are more sophisticated than those in vitro. The detection of a reduction in coherence length in the directions perpendicular to the planes onto which the proteins preferentially adsorbed represents one of very few direct demonstrations that an additive that is able to selectively alter crystal morphology also affects crystal texture in an anisotropically specific manner. An understanding of this phenomenon may, in the future, improve our ability to control crystal texture in synthetic materials. C1 WEIZMANN INST SCI,DEPT STRUCT BIOL,IL-76100 REHOVOT,ISRAEL. BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. WEIZMANN INST SCI,DEPT MAT,IL-76100 REHOVOT,ISRAEL. WEIZMANN INST SCI,DEPT INTERFACES,IL-76100 REHOVOT,ISRAEL. RI Hanson, jonathan/E-3517-2010; Berman, Amir/F-1870-2012 NR 27 TC 36 Z9 36 U1 0 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 MAY 13 PY 1993 VL 97 IS 19 BP 5162 EP 5170 DI 10.1021/j100121a052 PG 9 WC Chemistry, Physical SC Chemistry GA LB803 UT WOS:A1993LB80300052 ER PT J AU NAZAREWICZ, W AF NAZAREWICZ, W TI VARIETY OF SHAPES IN THE MERCURY AND LEAD ISOTOPES SO PHYSICS LETTERS B LA English DT Article ID SHELL-CORRECTION APPROACH; NEUTRON-DEFICIENT; EVEN EVEN; NUCLEI; COEXISTENCE; STATES; TRANSITIONS; DEFORMATION; ENERGIES; REGION AB Low-spin shape coexistence in the Hg and Pb isotopes is discussed within the shell correction approach with the axial, reflection-asymmetric Woods-Saxon model. For neutron deficient isotopes with N < 110 the calculations predict a competition between low-lying prolate and oblate shapes with quadrupole deformations ranging from very small (\beta2\ approximately 0.15) to very large (\beta2\ approximately 0.8). The classification of intruder states in terms of the intruder spin is discussed. C1 UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. RP NAZAREWICZ, W (reprint author), OAK RIDGE NATL LAB,JOINT INST HEAVY ION RES,POB 2008,OAK RIDGE,TN 37831, USA. NR 36 TC 171 Z9 171 U1 0 U2 10 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 MAY 13 PY 1993 VL 305 IS 3 BP 195 EP 201 DI 10.1016/0370-2693(93)90107-S PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA818 UT WOS:A1993LA81800003 ER PT J AU CHANG, D KEUNG, WY AF CHANG, D KEUNG, WY TI CP VIOLATION IN THE DECAY OF THE NEUTRAL HIGGS-BOSON INTO T-(T)BAR AND W(+)-W- SO PHYSICS LETTERS B LA English DT Article ID ELECTRIC-DIPOLE MOMENT; NONCONSERVATION; EXCHANGE; QUARKS AB We investigate a potentially large CP violating asymmetry in the neutral Higgs boson decay into a heavy quark pair or a W+-W-pair. The source of the CP nonconservation is in the Yukawa couplings of the Higgs boson which can contain both scalar and pseudoscalar pieces. One of the interesting consequences is the different rates of the Higgs boson decays into CP conjugate polarized states. The required final state interactions can be either the strong or the electroweak interactions. The CP violating asymmetry can manifest itself in the asymmetry in the energies of the secondary decay products of these heavy quarks and W bosons. Such asymmetry can be measureable in future colliders such as SSC or LHC. C1 ACAD SINICA,INST PHYS,TAIPEI 115,TAIWAN. UNIV ILLINOIS,DEPT PHYS,CHICAGO,IL 60680. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. RP CHANG, D (reprint author), NORTHWESTERN UNIV,DEPT PHYS & ASTRON,EVANSTON,IL 60208, USA. NR 22 TC 37 Z9 37 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 MAY 13 PY 1993 VL 305 IS 3 BP 261 EP 267 DI 10.1016/0370-2693(93)90116-Y PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA818 UT WOS:A1993LA81800012 ER PT J AU FALK, AF AF FALK, AF TI EXCITED HEAVY MESONS AND KAON LOOPS IN CHIRAL PERTURBATION-THEORY SO PHYSICS LETTERS B LA English DT Article ID FORM-FACTORS; QUARK; DECAYS AB We consider the effects of excited states on the SU (3) breaking chiral loop corrections to heavy meson properties. In particular, we compare the size of kaon loops in which an excited heavy meson appears to the size of previously calculated loops with heavy mesons in the ground state. We find that the new effects may indeed be of the same magnitude as the old ones, but that there is a strong dependence on the unknown masses and coupling constants of the new states. As a result, we argue that the ground state loops alone may not be a trustworthy guide to SU (3) corrections, and that the appropriate cutoff for a heavy-light chiral lagrangian which omits excited heavy mesons may be considerably smaller than the naive expectation of LAMBDA(chi) almost-equal-to 1 GeV. RP FALK, AF (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94305, USA. NR 19 TC 20 Z9 20 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 MAY 13 PY 1993 VL 305 IS 3 BP 268 EP 274 DI 10.1016/0370-2693(93)90117-Z PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA818 UT WOS:A1993LA81800013 ER PT J AU MICHOS, D LUO, XL CRABTREE, RH AF MICHOS, D LUO, XL CRABTREE, RH TI SYNTHESIS AND SOLUTION STRUCTURE OF HETEROBIMETALLIC RHENIUM-IRIDIUM POLYHYDRIDE COMPLEXES SO INORGANIC CHEMISTRY LA English DT Article ID X-RAY CRYSTAL; PHOSPHINE HEPTAHYDRIDE COMPLEXES; EARLY TRANSITION-METALS; C-H ACTIVATION; MOLECULAR-STRUCTURE; HYDRIDE COMPLEXES; HYDROGENATION CATALYSTS; ALKANE DEHYDROGENATION; CLASSICAL STRUCTURES; NEUTRON-DIFFRACTION AB The reaction of [IrH2(Me2CO)2(PPh3)2]SbF6 with ReH7(PPh3)2 or ReH7(dppf) (dppf = 1,1'-bis(diphenylphosphino)ferrocene) is extremely rapid and leads to the quantitative formation of the heterobimetallic polyhydride complexes [L2H3Re(mu-H)3IrH(PPh3)2]SbF6 (L = PPh3 (1), 1/2 dppf (2)), which have been characterized by IR and variable-temperature H-1 and P-31 NMR spectroscopy. The spectroscopic data for compounds 1 and 2 suggest that they contain three bridging and four terminal hydride ligands. The coordination polyhedron about rhenium is a dodecahedron, and that about iridium is an octahedron; the two polyhedra are fused by sharing a face containing the three bridging hydride ligands, which is an equilateral (E) triangular face of the dodecahedron and a triangular face of the octahedron. Compounds 1 and 2 are most likely formed by a formal dinuclear H-2 elimination mechanism, which involves initial displacement of the labile acetone ligands from [IrH2(Me2CO)2(PPh3)2]SbF6 by the hydride ligands of ReH7L2 to give a transient hydride-bridged dinuclear eta2-H-2 species which subsequently undergoes facile H-2 elimination. The geometric factors favoring or disfavoring M(mu-H)(n)M' (n=3-5) bridging systems are discussed. C1 LOS ALAMOS NATL LAB, INORGAN & STRUCT CHEM GRP INC1, MAIL STOP C346, LOS ALAMOS, NM 87545 USA. YALE UNIV, DEPT CHEM, STERLING CHEM LAB, NEW HAVEN, CT 06511 USA. NR 94 TC 10 Z9 10 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 EI 1520-510X J9 INORG CHEM JI Inorg. Chem. PD MAY 12 PY 1993 VL 32 IS 10 BP 2118 EP 2122 DI 10.1021/ic00062a040 PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA LC187 UT WOS:A1993LC18700040 ER PT J AU HUCKETT, SC SCOTT, B LOVE, SP DONOHOE, RJ BURNS, CJ GARCIA, E FRANKCOM, T SWANSON, BI AF HUCKETT, SC SCOTT, B LOVE, SP DONOHOE, RJ BURNS, CJ GARCIA, E FRANKCOM, T SWANSON, BI TI EFFECTS OF TEMPERATURE ON THE CRYSTAL AND MOLECULAR-STRUCTURE OF THE MIXED-VALENCE LINEAR-CHAIN [PT(EN)2][PT(EN)2X2](CLO4)4 (X = CL, BR) SO INORGANIC CHEMISTRY LA English DT Article ID RESONANCE RAMAN-SPECTROSCOPY; NONLINEAR LATTICE-RELAXATION; CHARGE-TRANSFER EXCITATION; PLATINUM COMPLEXES; POLARONIC STATES; METAL-COMPLEXES; SALT ANALOGS; ELECTRON; SOLITON; MODEL AB The crystal structures of the pure monoclinic and orthorhombic phases of [Pt(en)2][Pt(en)2Cl2](ClO4)4 (PtCl) and [Pt(en)2][Pt(en)2Br2](ClO4)4 (PtBr), with en = 1,2-diaminoethane, were determined at several temperatures. The monoclinic phase of PtCl has space group P2(1)/m, with a = 7.972(3) angstrom, b = 10.874(5) angstrom, c = 8.500(4) angstrom, beta = 108.91(4)-degrees, Z = 2, d = 2.619 g/cm3, and T = -20-degrees-C. The monoclinic phase of PtBr crystallizes in space group P2(1)/m, with a = 7.959(2) angstrom, b = 10.957(2) angstrom, c = 8.529(2) angstrom, beta = 109.32(3)-degrees, Z = 2, d = 2.811 g/CM3, and T = 25-degrees-C. The orthorhombic phase of PtCl has space group Ibam, with a = 13.594(4) angstrom, b = 9.657(5) angstrom, c = 10.855(4) angstrom, Z = 4, d = 2.562 g/cm3, and T = 25-degrees-C. The orthorhombic phase of PtBr crystallizes in space group Ibam, with a = 13.671(5) angstrom, b = 9.680(3) angstrom, c = 10.994(3) angstrom, Z = 4, d = 2.712 g/CM3, and T = 40-degrees-C. The monoclinic phases of PtCl and PtBr were also determined at T = -70 and -93-degrees-C, respectively. The lattice constants for PtCl(-70-degrees-C) are a = 7.947(4) angstrom, b = 10.871(5) angstrom, c = 8.445(5) angstrom, and beta = 108.79(4)-degrees, and the lattice constants for PtBr(-93-degrees-C) are a = 7.912(2) angstrom, b = 10.900(2) angstrom, c = 8.387(2) angstrom, and beta = 109.02(3)-degrees. The corresponding PtCl and PtBr phases are isostructural. These systems contain chains composed of alternating, octahedral Pt(en)2X2 and square planar (4 + 2) Pt(en)2 species; the axial halides of the octahedral species occupy semicoordinate axial sites of the square planar species. This motif results in alternating Pt-X distances along the chain, resulting in a charge density wave (CDW). The chains are linked together via a weak hydrogen-bonding network involving the NH2 hydrogens of the ethylenediamine ligands and the perchlorate counterions. The major structural differences between the phases are related to changes in the hydrogen bonding brought on by increased thermal motions of the perchlorate ions as the temperature is raised. These changes in hydrogen bonding alter crystal packing and incur subtle changes in PtX chain geometry and CDW strength. Raman spectroscopy measurements show a direct correlation between the frequency of the fundamental X-Pt-X stretch and the strength of the CDW. C1 LOS ALAMOS NATL LAB,SPECT & BIOCHEM GRP INC14,LOS ALAMOS,NM 87544. RI Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 48 TC 39 Z9 39 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAY 12 PY 1993 VL 32 IS 10 BP 2137 EP 2144 DI 10.1021/ic00062a044 PG 8 WC Chemistry, Inorganic & Nuclear SC Chemistry GA LC187 UT WOS:A1993LC18700044 ER PT J AU RAPKO, BM DUESLER, EN SMITH, PH PAINE, RT RYAN, RR AF RAPKO, BM DUESLER, EN SMITH, PH PAINE, RT RYAN, RR TI CHELATING PROPERTIES OF 2-((DIPHENYLPHOSPHINO)METHYL)PYRIDINE N,P-DIOXIDE AND 2,6-BIS((DIPHENYLPHOSPHINO)METHYL)PYRIDINE N,P,P'-TRIOXIDE TOWARD F-ELEMENT IONS SO INORGANIC CHEMISTRY LA English DT Article ID TRIPODAL LIGAND SYSTEM; <1,2-BIS(DIETHYLCARBAMOYL)ETHYL>PHOSPHONATE>ERBIUM(III) NITRATE; MOLECULAR-STRUCTURES; CRYSTAL; COORDINATION; LANTHANIDES; COMPLEXES; SAMARIUM AB The bifunctional 2-((diphenylphosphino)methyl)pyridine NP-dioxide, 2-[(C6H5)2P(O)CH2]C5H4NO (4), and trifunctional 2,6-bis((diphenylphosphino)methyl)pyridine NPP'-trioxide, 2,6-[(C6H5)2P(O)CH2]2C5H3NO (5), ligands have been prepared, and their coordination chemistry has been surveyed with Pr(III), Tb(III), Yb(III), and Th(IV). Single-crystal X-ray diffraction analyses have been completed for several complexes. Crystallographic data for [Tb(4)43+][(NO3)3(H2O)(EtOH)3-]: C74H72N7019P4Tb, orthorhombic, space group Pbca, a = 26.655(5) angstrom, b = 25.738(5) angstrom, c = 20.821(5) angstrom, z = 8, v = 14,284(5) angstrom3; structure refined to R(F) = 6.24% and R(wF) = 5.07% on 7068 data with F > 3sigma(F). The four ligands 4 produce a square antiprismatic coordination polyhedron. Crystallographic data for [Pr(4)2(NO3)3].Et2O.1/2 MeOH: C40.5H44N5014.5P2Pr, triclinic, space group P1BAR, a = 11.02(5) angstrom, b = 11.802(12) angstrom, c = 18.560(4) angstrom, alpha = 96.70(2)-degrees, beta = 95.84(3)-degrees, gamma = 108.55(3)-degrees, Z = 2, V = 2247.9(12) angstrom3; structure refined to R(F) = 6.80% and R(wF) = 5.65% on 4561 data with F > 2sigma(F). The Pr(III) is bonded to two bidentate ligands and three nitrate ions. Crystallographic data for [Yb(5)(NO3)3].MeOH: C32H31N4O13P2Yb, monoclinic, space group P2(1)/n, a = 11.677(2) angstrom, b = 15.764(3) angstrom, c = 20.242(3) angstrom, beta = 100.18(l)-degrees, Z = 4, V = 3667.4(9) angstrom3; structure refined to R(F) = 3.94% and R(wF) = 4.64% on 4680 data with F > 3sigma(F). The Yb(III) is bonded to 5 in a tridentate manner, along with three nitrate ions. Crystallographic data for [Yb(5)2(NO3)2+] [(NO3)2(H2O)2(CH3CN)2.52-]: C67H65.5N7.5O17P4Yb, triclinic, spacegroup P1BAR, a = 14.328(3) angstrom, b = 16.033(3) angstrom, c = 17.001(3) angstrom, a = 99.27(3)-degrees, beta = 101.92(3)-degrees, gamma = 107.36(3)-degrees, Z = 2, V = 3542(1) angstrom3; structure refined to R(F) = 5.64% and R(wF) = 7.32% on 10 711 data with F > 3sigma(F). The Yb is bonded to 5 in a tridentate fashion, along with one nitrate ion. Crystallographic data for [Th(5)2(NO3)22+][(NO3)2(H20)22-]: C62H54N6O20P4Th, monoclinic, spacegroup P2(1)/n, a = 19.136(4) angstrom, b = 18.365(4) angstrom, c = 21.448(4) angstrom, beta = 109.48(3)-degrees, Z = 4, V = 7106(3) angstrom3; structure refined to R(F) = 8.52% and R(wF) = 9.18% on 3518 data with F > 4sigma(F). Two tridentate ligands 5 and two nitrate ions are bonded to Th(IV). This coordination chemistry is compared with that displayed by the bifunctional ligand, 2-[(C6H5)2P(O)]C5H4NO. C1 UNIV NEW MEXICO,DEPT CHEM,ALBUQUERQUE,NM 87131. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. NR 30 TC 72 Z9 72 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAY 12 PY 1993 VL 32 IS 10 BP 2164 EP 2174 DI 10.1021/ic00062a047 PG 11 WC Chemistry, Inorganic & Nuclear SC Chemistry GA LC187 UT WOS:A1993LC18700047 ER PT J AU DIXIT, SN THOMAS, IM WOODS, BW MORGAN, AJ HENESIAN, MA WEGNER, PJ POWELL, HT AF DIXIT, SN THOMAS, IM WOODS, BW MORGAN, AJ HENESIAN, MA WEGNER, PJ POWELL, HT TI RANDOM-PHASE PLATES FOR BEAM SMOOTHING ON THE NOVA LASER SO APPLIED OPTICS LA English DT Article DE SOL-GEL COATINGS; RANDOM PHASE PLATES; BINARY-PHASE-ONLY DIFFRACTIVE OPTICAL ELEMENTS; LASER BEAM SMOOTHING ID UNIFORM ILLUMINATION; TARGETS AB We discuss the design and fabrication of 80-cm-diameter random phase plates for target-plane beam smoothing on the Nova laser. Random phase plates have been used in a variety of inertial confinement fusion target experiments, such as studying direct-drive hydrodynamic stability and producing spatially smooth x-ray backlighting sources. These phase plates were produced by using a novel sol-gel dip-coating technique developed by us. The sol-gel phase plates have a high optical damage threshold at the second- and third-harmonic wavelengths of the Nd:glass laser and have excellent optical performance. RP DIXIT, SN (reprint author), LAWRENCE LIVERMORE NATL LAB, POB 5508, LIVERMORE, CA 94551 USA. NR 27 TC 89 Z9 92 U1 0 U2 12 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD MAY 10 PY 1993 VL 32 IS 14 BP 2543 EP 2554 PG 12 WC Optics SC Optics GA LA800 UT WOS:A1993LA80000011 PM 20820416 ER PT J AU WU, XD FOLTYN, SR DYE, RC COULTER, Y MUENCHAUSEN, RE AF WU, XD FOLTYN, SR DYE, RC COULTER, Y MUENCHAUSEN, RE TI PROPERTIES OF EPITAXIAL SRRUO3 THIN-FILMS SO APPLIED PHYSICS LETTERS LA English DT Article AB SrRuO3 thin films were deposited on (100) LaAlO3 using pulsed laser deposition. The films were (001) oriented normal to the substrate surface with a high degree of in-plane orientation with respect to the substrate's major axes. An ion beam minimum yield of 2.5% was obtained for the films, indicating high crystallinity. The films exhibited metallic behavior with a room temperature resistivity of approximately 200 mW cm. A kink in the resistivity, corresponding to a ferromagnetic phase transition, was observed at approximately 160 K. It was found that SrRuO3 is structurally and chemically compatible with the YaB2Cu3O7-d (YBCO) superconductors. High quality YBCO films were obtained on SrRuO3 LaAlO3. Multilayers of YBCO/SrRuO3 were successfully fabricated. RP WU, XD (reprint author), LOS ALAMOS NATL LAB,CTR SUPERCONDUCT TECHNOL,LOS ALAMOS,NM 87545, USA. NR 8 TC 126 Z9 126 U1 2 U2 45 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 MAY 10 PY 1993 VL 62 IS 19 BP 2434 EP 2436 DI 10.1063/1.109388 PG 3 WC Physics, Applied SC Physics GA LA797 UT WOS:A1993LA79700047 ER PT J AU LINK, B EPSTEIN, RI PRIEDHORSKY, WC AF LINK, B EPSTEIN, RI PRIEDHORSKY, WC TI PREVALENT PROPERTIES OF GAMMA-RAY BURST VARIABILITY SO ASTROPHYSICAL JOURNAL LA English DT Article DE GAMMA RAYS, BURSTS AB With the aim of isolating universal characteristics of gamma-ray burst variability, we compare time histories for 20 bright bursts detected by the Burst and Transient Source Experiment. Using an autocorrelation function method, we find that the durations of individual structures within a burst, as well as the burst as a whole, become shorter with increasing energy in most events. We introduce the skewness function, a measure of temporal asymmetry. We find that most bursts exhibit a net skewness, in the sense that the intensity rises more rapidly than it falls. Over short time scales, bursts exhibit no preferrred asymmetry. Taken together, these properties suggest that the overall time structure of a burst is due to an explosive phenomenon in which the evolution is initially energetic and rapid and is later slower during a ''cooling'' period. We cannot rule out the possibility that short time-scale variability is caused by radiation beams sweeping past the observer. RP LINK, B (reprint author), LOS ALAMOS NATL LAB,MS-D436,LOS ALAMOS,NM 87545, USA. OI Epstein, Richard/0000-0002-3929-4363; Priedhorsky, William/0000-0003-0295-9138 NR 7 TC 74 Z9 78 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 MAY 10 PY 1993 VL 408 IS 2 BP L81 EP L84 DI 10.1086/186836 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LA025 UT WOS:A1993LA02500003 ER PT J AU FORTNER, J SABOUNGI, ML AF FORTNER, J SABOUNGI, ML TI RAMAN-SCATTERING IN LIQUID K-TE SO EUROPHYSICS LETTERS LA English DT Article ID NEUTRON-SCATTERING; ALLOYS; TELLURIUM; DENSITY AB Raman-scattering measurements from crystalline and liquid K0.12Te0.88 and K0.50Te0.50 semiconducting alloys are reported. The spectra of liquid K0.12Te0.88 are characterized by a single, weakly polarized band, markedly different from those obtained from pure liquid Te and bearing a greater similarity to the spectra reported for amorphous Te. The spectra of K0.50Te0.50 in the crystalline and liquid phases show remarkable similarities, confirming the presence of the Te2(2-) Zintl ion in both phases. Substantial softening of the symmetric stretching mode occurs relative to the equivalent mode in vapor and matrix-isolated Te2. This is most likely due to the charge transfer interaction with the K+ matrix. A comparison of structural data available for liquid and amorphous Te with those for liquid K0.12Te0.88 and K0.50Te0.50 indicates a transition to true 2-fold chainlike covalent bonding of Te in the liquid on addition of potassium. The importance of 2-fold bonding for the semiconducting behavior of Te-rich alloy systems in the liquid and solid states is discussed. RP FORTNER, J (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. RI Saboungi, Marie-Louise/C-5920-2013 OI Saboungi, Marie-Louise/0000-0002-0607-4815 NR 29 TC 9 Z9 9 U1 2 U2 3 PU EDITIONS PHYSIQUE PI LES ULIS CEDEX PA Z I DE COURTABOEUF AVE 7 AV DU HOGGAR, BP 112, 91944 LES ULIS CEDEX, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD MAY 10 PY 1993 VL 22 IS 5 BP 359 EP 364 DI 10.1209/0295-5075/22/5/007 PG 6 WC Physics, Multidisciplinary SC Physics GA LD526 UT WOS:A1993LD52600007 ER PT J AU TKACHOV, FV AF TKACHOV, FV TI EUCLIDEAN ASYMPTOTIC EXPANSIONS OF GREEN-FUNCTIONS OF QUANTUM-FIELDS .1. EXPANSIONS OF PRODUCT OF SINGULAR FUNCTIONS SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article AB The problem of asymptotic expansion of Green functions in perturbative QFT is studied for the class of Euclidean asymptotic regimes. Phenomenological applications are analyzed to obtain a meaningful mathematical formulation of the problem. It is shown that the problem reduces to studying asymptotic expansion of products of a class of singular functions in the sense of the distribution theory. Existence, uniqueness and explicit expressions for such expansions. (As-operation for products of singular functions) in dimensionally regularized form are obtained using the so-called extension principle. RP TKACHOV, FV (reprint author), FERMILAB NATL ACCELERATOR LAB,POB 500,BATAVIA,IL 60510, USA. NR 0 TC 51 Z9 51 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD MAY 10 PY 1993 VL 8 IS 12 BP 2047 EP 2117 DI 10.1142/S0217751X93000850 PG 71 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA LB628 UT WOS:A1993LB62800003 ER PT J AU KONCZYKOWSKI, M YESHURUN, Y KLEIN, L YACOBY, ER CHIKUMOTO, N VINOKUR, VM FEIGELMAN, MV AF KONCZYKOWSKI, M YESHURUN, Y KLEIN, L YACOBY, ER CHIKUMOTO, N VINOKUR, VM FEIGELMAN, MV TI FLUX-PINNING BY COLUMNAR DEFECTS IN HIGH-TEMPERATURE SUPERCONDUCTING CRYSTALS SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT SYMP ON HIGH TEMPERATURE SUPERCONDUCTORS, AT THE 1992 FALL MEETING OF THE E-MRS / 3RD EUROPEAN EAST-WEST CONF AND EXHIBITION ON MATERIALS AND PROCESSES CY NOV 03-06, 1992 CL STRASBOURG, FRANCE SP EUROPEAN MAT RES SOC, COUNCIL EUROPE, COMMISS EUROPEAN COMMUNITIES, BANQUE POPULAIRE, BRASSERIE KRONENBOURG, CTR RECH NUCLEAIRES, CTR RECH NUCLEAIRES, ELSEVIER SCI PUBL, OFF TOURISME VILLE STRASBOURG, EUROPEAN PARLIAMENT ID CU-O CRYSTALS; CRITICAL STATE; CREEP; OXIDES AB Y-Ba-Cu-O:123 and Bi-Sr-Ca-Cu-O:2212 crystals were irradiated with 5.8 GeV Pb ions. The columnar defects, produced by this irradiation are expected to yield the strongest possible pinning energy. Indeed, there is an apparent increase in the width of the magnetization curves. However, the results of magnetic relaxation experiments indicate the energy barrier for flux creep from the columnar defects much smaller than expected pinning energy. This effect is explained in terms of nucleation of vortex loop mechanism of flux creep. The estimate of pinning energy of columnar defect can be obtained from measurement of the angular dependence of the magnetization curves.. C1 BAR ILAN UNIV,IL-52900 RAMAT GAN,ISRAEL. UNIV TOKYO,BUNKYO KU,TOKYO 113,JAPAN. LANDAU THEORET PHYS INST,MOSCOW 117940,RUSSIA. ARGONNE NATL LAB,ARGONNE,IL 60439. RP KONCZYKOWSKI, M (reprint author), ECOLE POLYTECH,LSI,F-91128 PALAISEAU,FRANCE. RI Klein, Lior/B-1061-2008; Feigelman, Mikhail/M-4113-2013 OI Klein, Lior/0000-0002-1233-9453; NR 16 TC 8 Z9 8 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 MAY 10 PY 1993 VL 195 IS 1-2 BP 407 EP 410 DI 10.1016/0925-8388(93)90766-G PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA LC492 UT WOS:A1993LC49200095 ER PT J AU PRICE, DL SABOUNGI, ML SUSMAN, S VOLIN, KJ ENDERBY, JE BARNES, AC AF PRICE, DL SABOUNGI, ML SUSMAN, S VOLIN, KJ ENDERBY, JE BARNES, AC TI STRUCTURE OF 2 LIQUID SEMICONDUCTORS AG1-XSEX AND AG0.67TE0.33 SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID RANGE ORDER; ALLOYS AB Neutron diffraction measurements have been carried out on Ag1-xSex and Ag0.67Te0.33 alloys to investigate possible structural causes for the differences in electrical transport properties observed in the two alloys. Ag1-xSex was measured for three compositions, x = 0.30, 0.33 and 0.36, at temperatures just above the liquidus (1045, 915 and 855-degrees-C, respectively), and for x = 0.33 at three temperatures (915, 985 and 1045 C). The Ag1-xTex system was measured at only one composition x = 0.33, just above the liquidus (985-degrees-C). At the level of the average correlation function, the behaviour of liquid Ag-Se shows no unusual dependence on either concentration or temperature, and the selenium and tellurium alloys show generally similar behaviour. There is no obvious structural connection with the anomalous concentration dependence of the electrical conductivity in Ag1-xSex alloys or with the different behaviour in both electronic and ionic conduction observed in the Ag-Se and Ag-Te systems. C1 UNIV BRISTOL,HH WILLS PHYS LAB,BRISTOL BS8 1TL,AVON,ENGLAND. RP PRICE, DL (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Price, David Long/A-8468-2013; Saboungi, Marie-Louise/C-5920-2013 OI Saboungi, Marie-Louise/0000-0002-0607-4815 NR 14 TC 19 Z9 19 U1 0 U2 0 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 MAY 10 PY 1993 VL 5 IS 19 BP 3087 EP 3094 DI 10.1088/0953-8984/5/19/008 PG 8 WC Physics, Condensed Matter SC Physics GA LC026 UT WOS:A1993LC02600008 ER PT J AU KOVNER, A KURZEPA, P ROSENSTEIN, B AF KOVNER, A KURZEPA, P ROSENSTEIN, B TI A CANDIDATE FOR EXACT CONTINUUM DUAL THEORY FOR SCALAR QED3 SO MODERN PHYSICS LETTERS A LA English DT Article AB We discuss a possible exact equivalence of the Abelian Higgs model and a scalar theory of a magnetic vortex field in 2 + 1 dimensions. The vortex model has a current-current interaction and can be viewed as a strong coupling limit of a massive vector theory. The fixed point structure of the theory is and mapped into fixed points of the Higgs model. RP KOVNER, A (reprint author), LOS ALAMOS NATL LAB,DIV THEORY,T-8,MS B-285,LOS ALAMOS,NM 87545, USA. NR 0 TC 16 Z9 16 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0217-7323 J9 MOD PHYS LETT A JI Mod. Phys. Lett. A PD MAY 10 PY 1993 VL 8 IS 14 BP 1343 EP 1355 DI 10.1142/S0217732393001070 PG 13 WC Physics, Nuclear; Physics, Particles & Fields; Physics, Mathematical SC Physics GA LH070 UT WOS:A1993LH07000009 ER PT J AU ABT, I AHMED, T ANDREEV, V ANDRIEU, B APPUHN, RD ARPAGAUS, M BABAEV, A BARWOLFF, H BAN, J BARANOV, P BARRELET, E BARTEL, W BASSLER, U BECK, HP BEHREND, HJ BELOUSOV, A BERGER, C BERGSTEIN, H BERNARDI, G BERNET, R BERTRANDCOREMANS, G BESANCON, M BIDDULPH, P BINDER, E BISCHOFF, A BIZOT, JC BLOBEL, V BORRAS, K BOSETTI, PC BOUDRY, V BOURDARIOS, C BRASSE, F BRAUN, U BRAUNSCHWEIG, W BRISSON, V BRUNCKO, D BUNGENER, L BURGER, J BUSSER, FW BUNIATIAN, A BURKE, S BUSCHHORN, G CAMPBELL, AJ CARLI, T CHARLES, F CLARKE, D CLEGG, AB COLOMBO, M COUGHLAN, JA COURAU, A COUTURES, C COZZIKA, G CRIEGEE, L CVACH, J DAGORET, S DAINTON, JB DANILOV, M DANN, AWE DAU, WD DAVID, M DEFFUR, E DELCOURT, B DELBUONO, L DEVEL, M DEROECK, A DINGUS, P DOLLFUS, C DOWELL, JD DREIS, HB DRESCHER, A DUBOC, J DULLMANN, D DUNGER, O DUHM, H EBBINGHAUS, R EBERLE, M EBERT, J EBERT, TR ECKERLIN, G EFREMENKO, V EGLI, S EICHENBERGER, S EICHLER, R EISELE, F EISENHANDLER, E ELLIS, NN ELLISON, RJ ELSEN, E ERDMANN, M EVRARD, E FAVART, L FEDOTOV, A FEEKEN, D FELST, R FELTESSE, J FENSOME, IF FERENCEI, J FERRAROTTO, F FLAMM, K FLAUGER, W FLEISCHER, M FLUGGE, G FOMENKO, A FOMINYKH, B FORBUSH, M FORMANEK, J FOSTER, JM FRANKE, G FRETWURST, E FUHRMANN, P GABATHULER, E GAMERDINGER, K GARVEY, J GAYLER, J GELLRICH, A GENNIS, M GENZEL, H GERHARDS, R GILLESPIE, D GODFREY, L GOERLACH, U GOERLICH, L GOLDBERG, M GOODALL, AM GORELOV, I GORITCHEV, P GRAB, C GRASSLER, H GRASSLER, R GREENSHAW, T GREIF, H GRINDHAMMER, G GRUBER, C HAACK, J HAIDT, D HAJDUK, L HAMON, O HANDSCHUH, D HANLON, EM HAPKE, M HARJES, J HAYDAR, R HAYNES, WJ HEATHERINGTON, J HEDBERG, V HEINZELMANN, G HENDERSON, RCW HENSCHEL, H HERMA, R HERYNEK, I HILDESHEIM, W HILL, P HILTON, CD HLADKY, J HOEGER, KC HUET, P HUFNAGEL, H HUOT, N IBBOTSON, M ITTERBECK, H JABIOL, MA JACHOLKOWSKA, A JACOBSSON, C JAFFRE, M JANSEN, T JONSSON, L JOHANNSEN, K JOHNSON, DP JOHNSON, L JUNG, H KALMUS, PIP KASARIAN, S KASCHOWITZ, R KASSELMANN, P KATHAGE, U KAUFMANN, HH KENYON, IR KERMICHE, S KEUKER, C KIESLING, C KLEIN, M KLEINWORT, C KNIES, G KO, W KOHLER, T KOLANOSKI, H KOLE, F KOLYA, SD KORBEL, V KORN, M KOSTKA, P KOTELNIKOV, SK KRASNY, MW KREHBIEL, H KRUCKER, D KRUGER, U KUBENKA, JP KUSTER, H KUHLEN, M KURCA, T KURZHOFER, J KUZNIK, B LANDER, R LANDON, MPJ LANGE, W LANGKAU, R LANIUS, P LAPORTE, JF LEBEDEV, A LEUSCHNER, A LEVERENZ, C LEVONIAN, S LEWIN, D LEY, C LINDNER, A LINDSTROM, G LIPINSKI, J LOCH, P LOHMANDER, H LOPEZ, GC LUERS, D MAGNUSSEN, N MALINOVSKI, E MANI, S MARAGE, P MARKS, J MARSHALL, R MARTENS, J MARTIN, R MARTYN, HU MARTYNIAK, J MASSON, S MAVROIDIS, A MAXFIELD, SJ MCMAHON, SJ MEHTA, A MEIER, K MERCER, D MERZ, T MEYER, CA MEYER, H MEYER, J MIKOCKI, S MILONE, V MONNIER, E MOREAU, F MOREELS, J MORRIS, JV MULLER, K MURIN, P MURRAY, SA NAGOVIZIN, V NAROSKA, B NAUMANN, T NEWTON, D NEYRET, D NGUYEN, HK NIEBERGALL, F NISIUS, R NOWAK, G NOYES, GW NYBERG, M OBERLACK, H OBROCK, U OLSSON, JE ORENSTEIN, S OULDSAADA, F PASCAUD, C PATEL, GD PEPPEL, E PETERS, S PHARABOD, JP PHILLIPS, HT PHILLIPS, JP PICHLER, C PILGRAM, W PITZL, D PROSI, R RADEL, G RAUPACH, F RAUSCHNABEL, K REIMER, P RIBARICS, P RIECH, V RIEDLBERGER, J RIETZ, M ROBERTSON, SM ROBMANN, P ROOSEN, R ROSTOVTSEV, A ROYON, C RUDOWICZ, M RUFFER, M RUSAKOV, S RYBICKI, K SAHLMANN, N SANCHEZ, E SANKEY, DPC SAVITSKY, M SCHACHT, P SCHLEPER, P VONSCHLIPPE, W SCHMIDT, C SCHMIDT, D SCHMITZ, W SCHRODER, V SCHULZ, M SCHWIND, A SCOBEL, W SEEHAUSEN, U SELL, R SEMAN, M SEMENOV, A SHEKELYAN, V SHEVIAKOV, I SHOOSHTARI, H SIEGMON, G SIEWERT, U SIROIS, Y SKILLICORN, IO SMIRNOV, P SMITH, JR SMOLIK, L SOLOVIEV, Y SPITZER, H STAROBA, P STEENBOCK, M STEFFEN, P STEINBERG, R STELLA, B STEPHENS, K STIER, J STOSSLEIN, U STRACHOTA, J STRAUMANN, U STRUCZINSKI, W SUTTON, JP TAYLOR, RE THIEBAUX, C THOMPSON, G TICHOMIROV, I TRENKEL, C TRUOL, P TCHERNYSHOV, V TURNAU, J TUTAS, J URBAN, L USIK, A VALKAR, S VALKAROVA, A VALLEE, C VANESCH, P VARTAPETIAN, A VAZDIK, Y VECKO, M VERRECCHIA, P VICK, R VILLET, G VOGEL, E WACKER, K WALKER, IW WALTHER, A WEBER, G WEGENER, D WEGNER, A WELLISCH, HP WILLARD, S WINDE, M WINTER, GG WOLFF, T WOMERSLEY, LA WRIGHT, AE WULFF, N YIOU, TP ZACEK, J ZAVADA, P ZEITNITZ, C ZIAEEPOUR, H ZIMMER, M ZIMMERMANN, W ZOMER, F AF ABT, I AHMED, T ANDREEV, V ANDRIEU, B APPUHN, RD ARPAGAUS, M BABAEV, A BARWOLFF, H BAN, J BARANOV, P BARRELET, E BARTEL, W BASSLER, U BECK, HP BEHREND, HJ BELOUSOV, A BERGER, C BERGSTEIN, H BERNARDI, G BERNET, R BERTRANDCOREMANS, G BESANCON, M BIDDULPH, P BINDER, E BISCHOFF, A BIZOT, JC BLOBEL, V BORRAS, K BOSETTI, PC BOUDRY, V BOURDARIOS, C BRASSE, F BRAUN, U BRAUNSCHWEIG, W BRISSON, V BRUNCKO, D BUNGENER, L BURGER, J BUSSER, FW BUNIATIAN, A BURKE, S BUSCHHORN, G CAMPBELL, AJ CARLI, T CHARLES, F CLARKE, D CLEGG, AB COLOMBO, M COUGHLAN, JA COURAU, A COUTURES, C COZZIKA, G CRIEGEE, L CVACH, J DAGORET, S DAINTON, JB DANILOV, M DANN, AWE DAU, WD DAVID, M DEFFUR, E DELCOURT, B DELBUONO, L DEVEL, M DEROECK, A DINGUS, P DOLLFUS, C DOWELL, JD DREIS, HB DRESCHER, A DUBOC, J DULLMANN, D DUNGER, O DUHM, H EBBINGHAUS, R EBERLE, M EBERT, J EBERT, TR ECKERLIN, G EFREMENKO, V EGLI, S EICHENBERGER, S EICHLER, R EISELE, F EISENHANDLER, E ELLIS, NN ELLISON, RJ ELSEN, E ERDMANN, M EVRARD, E FAVART, L FEDOTOV, A FEEKEN, D FELST, R FELTESSE, J FENSOME, IF FERENCEI, J FERRAROTTO, F FLAMM, K FLAUGER, W FLEISCHER, M FLUGGE, G FOMENKO, A FOMINYKH, B FORBUSH, M FORMANEK, J FOSTER, JM FRANKE, G FRETWURST, E FUHRMANN, P GABATHULER, E GAMERDINGER, K GARVEY, J GAYLER, J GELLRICH, A GENNIS, M GENZEL, H GERHARDS, R GILLESPIE, D GODFREY, L GOERLACH, U GOERLICH, L GOLDBERG, M GOODALL, AM GORELOV, I GORITCHEV, P GRAB, C GRASSLER, H GRASSLER, R GREENSHAW, T GREIF, H GRINDHAMMER, G GRUBER, C HAACK, J HAIDT, D HAJDUK, L HAMON, O HANDSCHUH, D HANLON, EM HAPKE, M HARJES, J HAYDAR, R HAYNES, WJ HEATHERINGTON, J HEDBERG, V HEINZELMANN, G HENDERSON, RCW HENSCHEL, H HERMA, R HERYNEK, I HILDESHEIM, W HILL, P HILTON, CD HLADKY, J HOEGER, KC HUET, P HUFNAGEL, H HUOT, N IBBOTSON, M ITTERBECK, H JABIOL, MA JACHOLKOWSKA, A JACOBSSON, C JAFFRE, M JANSEN, T JONSSON, L JOHANNSEN, K JOHNSON, DP JOHNSON, L JUNG, H KALMUS, PIP KASARIAN, S KASCHOWITZ, R KASSELMANN, P KATHAGE, U KAUFMANN, HH KENYON, IR KERMICHE, S KEUKER, C KIESLING, C KLEIN, M KLEINWORT, C KNIES, G KO, W KOHLER, T KOLANOSKI, H KOLE, F KOLYA, SD KORBEL, V KORN, M KOSTKA, P KOTELNIKOV, SK KRASNY, MW KREHBIEL, H KRUCKER, D KRUGER, U KUBENKA, JP KUSTER, H KUHLEN, M KURCA, T KURZHOFER, J KUZNIK, B LANDER, R LANDON, MPJ LANGE, W LANGKAU, R LANIUS, P LAPORTE, JF LEBEDEV, A LEUSCHNER, A LEVERENZ, C LEVONIAN, S LEWIN, D LEY, C LINDNER, A LINDSTROM, G LIPINSKI, J LOCH, P LOHMANDER, H LOPEZ, GC LUERS, D MAGNUSSEN, N MALINOVSKI, E MANI, S MARAGE, P MARKS, J MARSHALL, R MARTENS, J MARTIN, R MARTYN, HU MARTYNIAK, J MASSON, S MAVROIDIS, A MAXFIELD, SJ MCMAHON, SJ MEHTA, A MEIER, K MERCER, D MERZ, T MEYER, CA MEYER, H MEYER, J MIKOCKI, S MILONE, V MONNIER, E MOREAU, F MOREELS, J MORRIS, JV MULLER, K MURIN, P MURRAY, SA NAGOVIZIN, V NAROSKA, B NAUMANN, T NEWTON, D NEYRET, D NGUYEN, HK NIEBERGALL, F NISIUS, R NOWAK, G NOYES, GW NYBERG, M OBERLACK, H OBROCK, U OLSSON, JE ORENSTEIN, S OULDSAADA, F PASCAUD, C PATEL, GD PEPPEL, E PETERS, S PHARABOD, JP PHILLIPS, HT PHILLIPS, JP PICHLER, C PILGRAM, W PITZL, D PROSI, R RADEL, G RAUPACH, F RAUSCHNABEL, K REIMER, P RIBARICS, P RIECH, V RIEDLBERGER, J RIETZ, M ROBERTSON, SM ROBMANN, P ROOSEN, R ROSTOVTSEV, A ROYON, C RUDOWICZ, M RUFFER, M RUSAKOV, S RYBICKI, K SAHLMANN, N SANCHEZ, E SANKEY, DPC SAVITSKY, M SCHACHT, P SCHLEPER, P VONSCHLIPPE, W SCHMIDT, C SCHMIDT, D SCHMITZ, W SCHRODER, V SCHULZ, M SCHWIND, A SCOBEL, W SEEHAUSEN, U SELL, R SEMAN, M SEMENOV, A SHEKELYAN, V SHEVIAKOV, I SHOOSHTARI, H SIEGMON, G SIEWERT, U SIROIS, Y SKILLICORN, IO SMIRNOV, P SMITH, JR SMOLIK, L SOLOVIEV, Y SPITZER, H STAROBA, P STEENBOCK, M STEFFEN, P STEINBERG, R STELLA, B STEPHENS, K STIER, J STOSSLEIN, U STRACHOTA, J STRAUMANN, U STRUCZINSKI, W SUTTON, JP TAYLOR, RE THIEBAUX, C THOMPSON, G TICHOMIROV, I TRENKEL, C TRUOL, P TCHERNYSHOV, V TURNAU, J TUTAS, J URBAN, L USIK, A VALKAR, S VALKAROVA, A VALLEE, C VANESCH, P VARTAPETIAN, A VAZDIK, Y VECKO, M VERRECCHIA, P VICK, R VILLET, G VOGEL, E WACKER, K WALKER, IW WALTHER, A WEBER, G WEGENER, D WEGNER, A WELLISCH, HP WILLARD, S WINDE, M WINTER, GG WOLFF, T WOMERSLEY, LA WRIGHT, AE WULFF, N YIOU, TP ZACEK, J ZAVADA, P ZEITNITZ, C ZIAEEPOUR, H ZIMMER, M ZIMMERMANN, W ZOMER, F TI A SEARCH FOR LEPTOQUARKS, LEPTOGLUONS AND EXCITED LEPTONS IN H1 AT HERA SO NUCLEAR PHYSICS B LA English DT Note ID Z0 DECAYS; SCALAR LEPTOQUARKS; EP-COLLIDERS; QUARKS; MODELS; LEP; COLLISIONS; PARTICLES; BOSONS; COLOR AB A direct search for new particles in the H1 experiment at HERA is presented for masses ranging from 35 GeV up to approximately 250 GeV. The data sample of 24 nb-1 accumulated during the first year of operation was analysed for signatures of scalar and vector leptoquarks, leptogluons, excited electrons and excited neutrinos with flavours of the first generation. No evidence for the production of such particles was found in various possible decay channels. Rejection limits are derived. C1 UNIV CALIF DAVIS,IIRPA,DAVIS,CA 95616. UNIV BIRMINGHAM,SCH PHYS & SPACE RES,BIRMINGHAM B15 2TT,W MIDLANDS,ENGLAND. PN LEBEDEV PHYS INST,MOSCOW,RUSSIA. ECOLE POLYTECH,CNRS,IN2P3,LPNHE,F-91128 PALAISEAU,FRANCE. DESY,W-2000 HAMBURG 52,GERMANY. SWISS FED INST TECHNOL,INST MITTELENERGIEPHYS,CH-8092 ZURICH,SWITZERLAND. MOSCOW THEORET & EXPTL PHYS INST,MOSCOW,RUSSIA. DESY,INST HOCHENERGIEPHYS,ZEUTHEN,GERMANY. SLOVAK ACAD SCI,INST EXPTL PHYS,KOSICE,CZECHOSLOVAKIA. UNIV PARIS 06,CNRS,IN2P3,LPNHE,PARIS,FRANCE. UNIV PARIS 07,CNRS,IN2P3,LPNHE,F-75221 PARIS 05,FRANCE. UNIV ZURICH,INST PHYS,CH-8006 ZURICH,SWITZERLAND. RHEIN WESTFAL TH AACHEN,INST PHYS 1,W-5100 AACHEN,GERMANY. INTERUNIV INST HIGH ENERGIES ULB VUB,BRUSSELS,BELGIUM. CTR ETUD SACLAY,DAPNIA,GIF SUR YVETTE,FRANCE. UNIV MANCHESTER,DEPT PHYS,MANCHESTER M13 9PL,LANCS,ENGLAND. UNIV PARIS 11,CNRS,IN2P3,LAL,F-91405 ORSAY,FRANCE. UNIV HAMBURG,INST EXPTL PHYS 2,W-2000 HAMBURG 13,GERMANY. UNIV DORTMUND,INST PHYS,W-4600 DORTMUND 50,GERMANY. RHEIN WESTFAL TH AACHEN,INST PHYS 3,W-5100 AACHEN,GERMANY. YEREVAN PHYS INST,YEREVAN,ARMENIA. UNIV LIVERPOOL,DEPT PHYS,LIVERPOOL L69 3BX,ENGLAND. MAX PLANCK INST PHYS & ASTROPHYS,MUNICH,GERMANY. UNIV GLASGOW,DEPT PHYS & ASTRON,GLASGOW G12 8QQ,SCOTLAND. RUTHERFORD APPLETON LAB,DIDCOT OX11 0QX,OXON,ENGLAND. UNIV LANCASTER,SCH PHYS & MAT,LANCASTER LA1 4YW,ENGLAND. CHRISTIAN ALBRECHTS UNIV KIEL,INST REINE & ANGEW KERNPHYS,W-2300 KIEL 1,GERMANY. UNIV HAMBURG,INST EXPTL PHYS 1,W-2000 HAMBURG 13,GERMANY. BERG UNIV GESAMTHSCH WUPPERTAL,FACHBEREICH PHYS,WUPPERTAL,GERMANY. UNIV HEIDELBERG,INST PHYS,W-6900 HEIDELBERG,GERMANY. QUEEN MARY & WESTFIELD COLL,LONDON,ENGLAND. UNIV ROMA LA SAPIENZA,DIPARTIMENTO FIS,I-00185 ROME,ITALY. UNIV ROMA LA SAPIENZA,INFN ROMA,I-00185 ROME,ITALY. CHARLES UNIV,CTR NUCL,CS-11636 PRAGUE 1,CZECHOSLOVAKIA. INST NUCL PHYS,PL-31342 KRAKOW,POLAND. CZECHOSLOVAK ACAD SCI,INST PHYS,PRAGUE,CZECHOSLOVAKIA. STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94305. UNIV HEIDELBERG,INST HOCHENERGIEPHYS,W-6900 HEIDELBERG,GERMANY. LUND UNIV,DEPT PHYS,LUND,SWEDEN. RP ABT, I (reprint author), UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616, USA. RI Danilov, Mikhail/C-5380-2014; Kotelnikov, Sergey/A-9711-2014; Cvach, Jaroslav/G-6269-2014; Staroba, Pavel/G-8850-2014; DEVEL, Michel/A-5677-2009; Sheviakov, Igor/N-2735-2015; Meyer, Curtis/L-3488-2014; Soloviev, Yury/M-8788-2015; Levonian, Sergey/M-8693-2015; Andreev, Vladimir/M-8665-2015; Fomenko, Alexander/I-7900-2014; Malinovski, Evgenii/N-1034-2015; Belousov, Anatoli/N-2102-2015; Vazdik, Iakov/N-2624-2015; Gorelov, Igor/J-9010-2015 OI Danilov, Mikhail/0000-0001-9227-5164; Kotelnikov, Sergey/0000-0002-8027-4612; Beck, Hans Peter/0000-0001-7212-1096; Bassler, Ursula/0000-0002-9041-3057; DEVEL, Michel/0000-0001-8785-6896; Sheviakov, Igor/0000-0002-1659-3483; Meyer, Curtis/0000-0001-7599-3973; Soloviev, Yury/0000-0003-1136-2827; Gorelov, Igor/0000-0001-5570-0133 NR 66 TC 74 Z9 74 U1 0 U2 2 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 MAY 10 PY 1993 VL 396 IS 1 BP 3 EP 23 DI 10.1016/0550-3213(93)90255-N PG 21 WC Physics, Particles & Fields SC Physics GA LC940 UT WOS:A1993LC94000001 ER PT J AU CHAUDHURI, S LYKKEN, JD AF CHAUDHURI, S LYKKEN, JD TI STRING THEORY, BLACK-HOLES, AND SL(2, R) CURRENT-ALGEBRA SO NUCLEAR PHYSICS B LA English DT Article ID CONFORMAL FIELD-THEORIES; VIRASORO ALGEBRAS; MODELS; SURFACES; GRAVITY; STATES AB We analyse in detail the SL(2, R) black hole by extending standard techniques of Kac-Moody current algebra to the non-compact case. We construct the elements of the ground ring and exhibit W(infinity) type structure in the fusion algebra of the discrete states. As a consequence, we can identify some of the exactly marginal deformations of the black hole. We show that these deformations alter not only the spacetime metric but also turn on non-trivial backgrounds for the tachyon and all of the massive modes of the string. RP CHAUDHURI, S (reprint author), FERMILAB NATL ACCELERATOR LAB,THEORY GRP,MS106,POB 500,BATAVIA,IL 60510, USA. NR 66 TC 25 Z9 25 U1 0 U2 1 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 MAY 10 PY 1993 VL 396 IS 1 BP 270 EP 302 DI 10.1016/0550-3213(93)90267-S PG 33 WC Physics, Particles & Fields SC Physics GA LC940 UT WOS:A1993LC94000013 ER PT J AU GREGORY, R LAFLAMME, R AF GREGORY, R LAFLAMME, R TI BLACK STRINGS AND P-BRANES ARE UNSTABLE SO PHYSICAL REVIEW LETTERS LA English DT Article ID HOLES AB We investigate the evolution of small perturbations around black strings and branes which are low energy solutions of string theory. For simplicity we focus attention on the zero charge case and show that there are unstable modes for a range of time frequency and wavelength in the extra 10 - D dimensions. These perturbations can be stabilized if the extra dimensions are compactified to a scale smaller than the minimum wavelength for which instability occurs and thus will not affect large astrophysical black holes in four dimensions. We comment on the implications of this result for the cosmic censorship hypothesis. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP GREGORY, R (reprint author), UNIV CHICAGO,ENRICO FERMI INST,5640 S ELLIS AVE,CHICAGO,IL 60637, USA. NR 19 TC 652 Z9 652 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 MAY 10 PY 1993 VL 70 IS 19 BP 2837 EP 2840 DI 10.1103/PhysRevLett.70.2837 PG 4 WC Physics, Multidisciplinary SC Physics GA LB099 UT WOS:A1993LB09900004 ER PT J AU YOU, H CHIARELLO, RP KIM, HK VANDERVOORT, KG AF YOU, H CHIARELLO, RP KIM, HK VANDERVOORT, KG TI X-RAY REFLECTIVITY AND SCANNING-TUNNELING-MICROSCOPE STUDY OF KINETIC ROUGHENING OF SPUTTER-DEPOSITED GOLD-FILMS DURING GROWTH SO PHYSICAL REVIEW LETTERS LA English DT Article ID GROWING INTERFACES; PHASE-TRANSITION; SURFACE-GROWTH; ACTIVE ZONE; MODEL; DIFFUSION AB An in situ x-ray reflectivity study of the dynamic evolution of a growing interface was carried out for gold sputter-deposited onto a polished silicon substrate. X-ray reflectivity data were recorded during growth for thicknesses of the gold film ranging from 50 to 3500 angstrom. A progressive kinetic roughening of the gold-vacuum interface was observed and the time-dependent interfacial width exhibits a power-law behavior. Aided by scanning-tunneling-microscopy measurements the scaling exponents were determined and compared with theoretical studies. RP YOU, H (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI You, Hoydoo/A-6201-2011; Kim, Hyung-Kook/J-2065-2012 OI You, Hoydoo/0000-0003-2996-9483; Kim, Hyung-Kook/0000-0003-4974-5233 NR 23 TC 144 Z9 146 U1 3 U2 13 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 MAY 10 PY 1993 VL 70 IS 19 BP 2900 EP 2903 DI 10.1103/PhysRevLett.70.2900 PG 4 WC Physics, Multidisciplinary SC Physics GA LB099 UT WOS:A1993LB09900020 ER PT J AU DAEMEN, LL CAMPBELL, LJ SIMONOV, AY KOGAN, VG AF DAEMEN, LL CAMPBELL, LJ SIMONOV, AY KOGAN, VG TI COEXISTENCE OF 2 FLUX-LINE SPECIES IN SUPERCONDUCTING SLABS SO PHYSICAL REVIEW LETTERS LA English DT Article ID VORTICES AB Within the London approximation, we show that in anisotropic, strongly type II superconducting slabs two ''species'' of vortices can coexist simultaneously when the external magnetic field is applied at an angle with respect to the crystal principal axes. Simple thermodynamic arguments are used to prove that the appropriate thermodynamic potential is minimum when some of the vortices lie parallel to the c axis while others lie at an angle with respect to the c axis. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. RP DAEMEN, LL (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. RI Lujan Center, LANL/G-4896-2012; Simonov, Andrei/C-1697-2015 OI Simonov, Andrei/0000-0001-6452-0214 NR 14 TC 38 Z9 38 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 10 PY 1993 VL 70 IS 19 BP 2948 EP 2951 DI 10.1103/PhysRevLett.70.2948 PG 4 WC Physics, Multidisciplinary SC Physics GA LB099 UT WOS:A1993LB09900032 ER PT J AU DESOTO, SM SLICHTER, CP WANG, HH GEISER, U WILLIAMS, JM AF DESOTO, SM SLICHTER, CP WANG, HH GEISER, U WILLIAMS, JM TI EVIDENCE FOR THE ROLE OF FLUXOIDS IN ENHANCING NMR SPIN-LATTICE RELAXATION AND IMPLICATIONS FOR INTRINSIC PINNING OF THE FLUX LATTICE IN ORGANIC SUPERCONDUCTORS SO PHYSICAL REVIEW LETTERS LA English DT Article ID BEDT-TTF; BETA-(BEDT-TTF)2I3; TRANSITION; BIS(ETHYLENEDITHIO)TETRATHIAFULVALENE; KAPPA-(BEDT-TTF)2CUBR; (BEDT-TTF)2CU(NCS)2; TEMPERATURE; BEHAVIOR AB The authors report H-1 NMR spin-lattice relaxation rates, T1(-1), in the quasi-2D organic superconductor kappa-(ET)2Cu[N(CN)2]Br (T(c)=11.6 K), for an aligned single crystal. The relaxation in the normal state obeys the Korringa law (T1T=const). In the superconducting state, for weak fields (H0 almost-equal-to 0.59 T), T1(-1) is greatly enhanced and displays strong orientation dependence for field directions nearly parallel to the superconducting layers. This behavior indicates that motion of the fluxoid system is the cause of the extra relaxation, and is evidence for a ''lock-in'' transition of the flux lattice. C1 UNIV ILLINOIS,MAT RES LAB,URBANA,IL 61801. ARGONNE NATL LAB,DIV CHEM & MAT SCI,ARGONNE,IL 60439. RP DESOTO, SM (reprint author), UNIV ILLINOIS,DEPT PHYS,1110 W GREEN ST,URBANA,IL 61801, USA. NR 29 TC 51 Z9 51 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 MAY 10 PY 1993 VL 70 IS 19 BP 2956 EP 2959 DI 10.1103/PhysRevLett.70.2956 PG 4 WC Physics, Multidisciplinary SC Physics GA LB099 UT WOS:A1993LB09900034 ER PT J AU ALMEIDA, T COX, LE WARD, JW NAEGELE, JR AF ALMEIDA, T COX, LE WARD, JW NAEGELE, JR TI GAS-ADSORPTION STUDIES ON PU METAL BY PHOTOEMISSION SPECTROSCOPY SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 8TH INTERNATIONAL CONF ON SOLID SURFACES ( ICSS-8 ) / 12TH INTERNATIONAL VACUUM CONGRESS ( IVC-12 ) CY OCT 12-16, 1992 CL THE HAGUE, NETHERLANDS SP INT UNION VACUUM SCI TECH & APPLICAT ID CO; SURFACES; PD(111) AB In the context of elucidating the role of the 5f electrons in the reactivity of actinides, the adsorption of O2, CO2, CO and C2H4 on Pu metal has been studied at 77 and 296 K by UPS and XPS. For 02 at 77 and 296 K, Pu2O3 is formed initially and followed by an oxidation to PuO2. PuO2 formation occurs at higher dosages (60 L) at 296 K than at 77 K. At 77 K, CO2 is dissociated for low dosages (2 L). At higher exposures (> 4 L) new emission lines in UPS are observed and are attributed to carbonate formation. For higher dosages (> 20 L) CO2 physisorbs. At 296 K, the behavior is similar to that at 77 K with the exception that physisorbed CO2 is not observed. Low dosages (4 L) of CO at 77 K results in dissociation of the molecule. At higher dosages (> 6 L) chemisorbed CO is detected. At 296 K, CO behaves in the same way as CO2 at this temperature. For both CO2 and CO, the dissociation of the gases is always followed by the formation of some amount of PU2O3. For C2H4 at 77 and 296 K, dissociation of the gas is followed either by formation of PuC or chemisorbed C. The formation of some PuH2 is also observed. At 77 K, and high dosages (100 L), a very weak physisorbed phase of C2H4 can be observed. These results are quite different from those for U metal, for which dissociation of the gases was observed at all temperatures, and additionally at low temperatures CO2, CO and C2H4 are physisorbed at exposures higher than 6 L. It is not yet, however, clear, how this large variety of surface reactivity in the actinide series is related to the gradual localization of 5f electrons. C1 ICEN, DEPT QUIM, LNETI, P-2686 SACAVEM, PORTUGAL. LOS ALAMOS NATL LAB, DIV MAT SCI & TECHNOL, LOS ALAMOS, NM 87545 USA. RP ALMEIDA, T (reprint author), JRC, INST TRANSURANIUM ELEMENTS, COMMISS EUROPEAN COMMUNITIES, POSTFACH 2340, W-7500 KARLSRUHE, GERMANY. RI Gasche, Teresa/J-9849-2013 OI Gasche, Teresa/0000-0002-2391-8784 NR 22 TC 19 Z9 26 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 10 PY 1993 VL 287 BP 141 EP 145 DI 10.1016/0039-6028(93)90758-C PN A PG 5 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA LD370 UT WOS:A1993LD37000028 ER PT J AU SILLER, L HOCK, KM PALMER, RE WENDELKEN, JF AF SILLER, L HOCK, KM PALMER, RE WENDELKEN, JF TI RESONANCE ELECTRON-SCATTERING BY ADSORBED MOLECULES - SIGMA-ASTERISK RESONANCE ENERGY VERSUS BOND LENGTH SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 8TH INTERNATIONAL CONF ON SOLID SURFACES ( ICSS-8 ) / 12TH INTERNATIONAL VACUUM CONGRESS ( IVC-12 ) CY OCT 12-16, 1992 CL THE HAGUE, NETHERLANDS SP INT UNION VACUUM SCI TECH & APPLICAT ID ABSORPTION FINE-STRUCTURE; NEAR-EDGE; CO; ORIENTATION; PT(111); SHELL AB This paper explores the relationship between the energy of the sigma* negative ion resonance, observed in the cross-section for vibrational excitation of small molecules in electron energy-loss spectroscopy (EELS), and the intramolecular bond length. On the basis of experimental results assembled from studies of electron scattering by both free and adsorbed molecules containing the C-O group, we find an approximately linear empirical correlation between the resonance energy and the C-O bond length. This correlation is accurately reproduced by multiple-scattering Xalpha calculations for the free CO molecule as a function of bond length, suggesting the possible determination of molecular bond lengths from the sigma* resonance energies obtained in EELS. Similar calculations are reported for N2 and O2 in addition to CO. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. RP SILLER, L (reprint author), UNIV CAMBRIDGE,CAVENDISH LAB,MADINGLEY RD,CAMBRIDGE CB3 0HE,ENGLAND. RI Palmer, Richard/A-5366-2008 OI Palmer, Richard/0000-0001-8728-8083 NR 26 TC 7 Z9 7 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 10 PY 1993 VL 287 BP 165 EP 168 PN A PG 4 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA LD370 UT WOS:A1993LD37000033 ER PT J AU SANDY, AR MOCHRIE, SGJ ZEHNER, DM GRUBEL, G HUANG, KG GIBBS, D AF SANDY, AR MOCHRIE, SGJ ZEHNER, DM GRUBEL, G HUANG, KG GIBBS, D TI AU(111) AND PT(111) SURFACE PHASE-BEHAVIOR SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 8TH INTERNATIONAL CONF ON SOLID SURFACES ( ICSS-8 ) / 12TH INTERNATIONAL VACUUM CONGRESS ( IVC-12 ) CY OCT 12-16, 1992 CL THE HAGUE, NETHERLANDS SP INT UNION VACUUM SCI TECH & APPLICAT ID COMMENSURATE-INCOMMENSURATE TRANSITION; RAY-SCATTERING MEASUREMENTS; X-RAY; AU(001) SURFACE; RECONSTRUCTIONS; DISLOCATIONS AB We describe our recent X-ray scattering studies of the structure and phases of the clean Au(111) and Pt(111) surfaces. Below 0.65 of their respective bulk melting temperatures, the Au(111) surface has a well-ordered chevron reconstruction and the Pt(111) surface is unreconstructed. Above these temperatures, both surfaces reconstruct to form layers that are isotropically compresses and have only short-range order. Throughout their reconstructed phases, the densities of the Au and Pt(111) surfaces increase with increasing temperature. C1 MIT,DEPT PHYS,CAMBRIDGE,MA 02139. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. NR 19 TC 3 Z9 3 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 10 PY 1993 VL 287 BP 321 EP 324 DI 10.1016/0039-6028(93)90795-L PN A PG 4 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA LD370 UT WOS:A1993LD37000065 ER PT J AU VANHOVE, MA MORITZ, W OVER, H ROUS, PJ WANDER, A BARBIERI, A MATERER, N STARKE, U JENTZ, D POWERS, JM HELD, G SOMORJAI, GA AF VANHOVE, MA MORITZ, W OVER, H ROUS, PJ WANDER, A BARBIERI, A MATERER, N STARKE, U JENTZ, D POWERS, JM HELD, G SOMORJAI, GA TI FITTING DOZENS OF COORDINATES BY LEED - AUTOMATED-DETERMINATION OF COMPLEX SURFACE-STRUCTURES SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 8TH INTERNATIONAL CONF ON SOLID SURFACES ( ICSS-8 ) / 12TH INTERNATIONAL VACUUM CONGRESS ( IVC-12 ) CY OCT 12-16, 1992 CL THE HAGUE, NETHERLANDS SP INT UNION VACUUM SCI TECH & APPLICAT ID ENERGY-ELECTRON-DIFFRACTION; RECONSTRUCTION AB We present the first comprehensive discussion of automatic optimization procedures for surface-structure determination by LEED. These procedures combine numerical search algorithms with efficient methods of determining the diffracted intensities for varying structures. Such approaches can reduce the computer time required for an entire structure determination by many orders of magnitude, while fitting many times more unknown structural parameters. Thereby, relatively complex structures, with typically 10 adjustable atoms (or 30 adjustable coordinates), can be readily determined on today's workstations. We list over two dozen structures so determined, many as yet unpublished. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. UNIV MUNICH,INST KRISTALLOG & MINERAL,W-8000 MUNICH 2,GERMANY. MAX PLANCK GESELL,FRITZ HABER INST,W-1000 BERLIN 33,GERMANY. UNIV MARYLAND BALTIMORE CTY,DEPT PHYS,CATONSVILLE,MD 21228. UNIV CAMBRIDGE,DEPT PHYS CHEM,CAMBRIDGE CB2 1EW,ENGLAND. INTEL CORP,HILLSBORO,OR 97124. TECH UNIV MUNICH,DEPT PHYS E20,W-8046 GARCHING,GERMANY. RP VANHOVE, MA (reprint author), LAWRENCE BERKELEY LAB,DIV MAT SCI,CTR ADV MAT,BERKELEY,CA 94720, USA. RI Van Hove, Michel/A-9862-2008; Held, Georg/D-5468-2013; OI Van Hove, Michel/0000-0002-8898-6921; Held, Georg/0000-0003-0726-4183 NR 34 TC 11 Z9 11 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 10 PY 1993 VL 287 BP 428 EP 431 DI 10.1016/0039-6028(93)90817-4 PN A PG 4 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA LD370 UT WOS:A1993LD37000087 ER PT J AU STARKE, U MATERER, N BARBIERI, A DOLL, R HEINZ, K VANHOVE, MA SOMORJAI, GA AF STARKE, U MATERER, N BARBIERI, A DOLL, R HEINZ, K VANHOVE, MA SOMORJAI, GA TI A LOW-ENERGY-ELECTRON DIFFRACTION STUDY OF OXYGEN, WATER AND ICE ADSORPTION ON PT(111) SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 8TH INTERNATIONAL CONF ON SOLID SURFACES ( ICSS-8 ) / 12TH INTERNATIONAL VACUUM CONGRESS ( IVC-12 ) CY OCT 12-16, 1992 CL THE HAGUE, NETHERLANDS SP INT UNION VACUUM SCI TECH & APPLICAT ID DIFFUSE LEED; X 2)-O; SURFACE; INTENSITIES; RELIABILITY AB We present low-energy electron diffraction (LEED) studies of a p(2 x 2) overlayer of oxygen, a monolayer of water and a multilayer ice film on Pt(111). Oxygen adsorbs in a fcc hollow site; buckling in the first two substrate layers leads to a local expansion of the substrate underneath the oxygen. Water adsorbs as a disordered monolayer and diffuse LEED intensities (DLEED) can be observed. From the structure of the diffuse background preferred next-neighbor distances can be concluded. A multilayer of water forms a thick molecular crystal of ice grown in (square-root 3 x square-root 3)R30-degrees periodicity on Pt(111). C1 UNIV ERLANGEN NURNBERG,LEHRSTUHL FESTKORPERPHYS,W-8520 ERLANGEN,GERMANY. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RP STARKE, U (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720, USA. RI Van Hove, Michel/A-9862-2008 OI Van Hove, Michel/0000-0002-8898-6921 NR 20 TC 60 Z9 60 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 10 PY 1993 VL 287 BP 432 EP 437 DI 10.1016/0039-6028(93)90818-5 PN A PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA LD370 UT WOS:A1993LD37000088 ER PT J AU GRUBEL, G GIBBS, D ZEHNER, DM ABERNATHY, DL SANDY, AR MOCHRIE, SGJ AF GRUBEL, G GIBBS, D ZEHNER, DM ABERNATHY, DL SANDY, AR MOCHRIE, SGJ TI PHASE-BEHAVIOR OF AU AND PT SURFACES SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 8TH INTERNATIONAL CONF ON SOLID SURFACES ( ICSS-8 ) / 12TH INTERNATIONAL VACUUM CONGRESS ( IVC-12 ) CY OCT 12-16, 1992 CL THE HAGUE, NETHERLANDS SP INT UNION VACUUM SCI TECH & APPLICAT, NETHERLANDS VACUUM SOC ID RAY-SCATTERING MEASUREMENTS; AU(001) SURFACE; ORIENTATIONAL EPITAXY; AU(111) SURFACE; STRESS TENSOR; RECONSTRUCTIONS; MONOLAYERS; TRANSITION; PLATINUM; GRAPHITE AB We summarize the results of X-ray scattering studies of the Au(001) and Pt(001) surfaces between 300 K and their respective bulk melting temperatures (T(m)). Both surfaces exhibit three distinct structural phases. At high temperatures (0.88T(m) < T < T(m)) both surfaces are disordered. The Pt(001) surface is rough. At a temperature of T/T(m) almost-equal-to 0.88 there are reversible phase transformations to incommensurate, corrugated-hexagonal phases. Below T/T(m) almost-equal-to 0.8 hexagonal domains rotate with respect to the substrate orientation. In Pt, the rotational transformation is continuous and shows mean-field behavior. In Au, the rotational transformation is mainly discontinuous. C1 RISO NATL LAB,DEPT PHYS,DK-4000 ROSKILDE,DENMARK. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. MIT,DEPT PHYS,CAMBRIDGE,MA 02139. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP GRUBEL, G (reprint author), EUROPEAN SYNCHROTRON RADIAT FACIL,DIV EXPT,BP 220,F-38043 GRENOBLE,FRANCE. RI Abernathy, Douglas/A-3038-2012 OI Abernathy, Douglas/0000-0002-3533-003X NR 22 TC 2 Z9 2 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 10 PY 1993 VL 287 BP 842 EP 846 DI 10.1016/0039-6028(93)91084-3 PN B PG 5 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA LF071 UT WOS:A1993LF07100059 ER PT J AU CAPASSO, C NG, W RAYCHAUDHURI, AK LIANG, SH COLE, RK GUO, ZY WALLACE, J CERRINA, F UNDERWOOD, J PERERA, R KORTRIGHT, J DE STASIO, G MARGARITONDO, G AF CAPASSO, C NG, W RAYCHAUDHURI, AK LIANG, SH COLE, RK GUO, ZY WALLACE, J CERRINA, F UNDERWOOD, J PERERA, R KORTRIGHT, J DE STASIO, G MARGARITONDO, G TI SCANNING PHOTOEMISSION MICROSCOPY ON MAXIMUM REACHES 0.1 MICRON RESOLUTION SO SURFACE SCIENCE LA English DT Article ID ENERGY-LOSS SPECTROSCOPY; PHOTOELECTRON MICROSCOPY; SYNCHROTRON RADIATION; UNDULATOR; SPECTROMICROSCOPY; LIMITATIONS; NEURONS; SILICON AB We present the first results from the upgraded version of the scanning photoemission spectromicroscope MAXIMUM, bared on synchrotron undulator fight and on a multilayer-coated Schwarzschild objective. The upgrade involved nearly all parts of the instrument, notably the beamline and the electron analysis system. Micro-images of Fresnel zone plates and of metal test patterns on semiconductor substrates reached a new record in lateral resolution, well beyond 0.1 micron. The first spectromicroscopy tests were also successfully performed on the new instrument, with analysis of f and d core levels in different systems. C1 LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. CNR, IST STRUTTURA MAT, FRASCATI, ITALY. ECOLE POLYTECH FED LAUSANNE, INST PHYS APPL, CH-1015 LAUSANNE, SWITZERLAND. RP CAPASSO, C (reprint author), UNIV WISCONSIN, CTR XRAY LITHOG, STOUGHTON, WI 53589 USA. RI Margaritondo, Giorgio/B-1367-2008; Gilbert, Pupa/A-6299-2010 OI Gilbert, Pupa/0000-0002-0139-2099 NR 28 TC 17 Z9 17 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 10 PY 1993 VL 287 BP 1046 EP 1050 DI 10.1016/0039-6028(93)91124-8 PN B PG 5 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA LF071 UT WOS:A1993LF07100099 ER PT J AU JESSON, DE PENNYCOOK, SJ AF JESSON, DE PENNYCOOK, SJ TI INCOHERENT IMAGING OF THIN SPECIMENS USING COHERENTLY SCATTERED ELECTRONS SO PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article ID HIGH-RESOLUTION; MICROSCOPY; IMAGES; STEM; SUPERLATTICES; CONTRAST; CRYSTALS AB We consider the imaging of phase objects using a scanning transmission electron microscope equipped with a large inner-angle annular detector. We show, contrary to popular expectation, that incoherent imaging theory can be used to describe the imaging process in a plane perpendicular to the optical axis. Interference effects between atoms possessing the same projected coordinates must, however, be considered explicitly. RP JESSON, DE (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. OI Jesson, David/0000-0003-0897-1445 NR 38 TC 109 Z9 109 U1 1 U2 22 PU ROYAL SOC LONDON PI LONDON PA 6 CARLTON HOUSE TERRACE, LONDON, ENGLAND SW1Y 5AG SN 1364-5021 J9 P ROY SOC LOND A MAT JI Proc. R. Soc. London Ser. A-Math. Phys. Eng. Sci. PD MAY 8 PY 1993 VL 441 IS 1912 BP 261 EP 281 DI 10.1098/rspa.1993.0060 PG 21 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA LC216 UT WOS:A1993LC21600003 ER PT J AU GURGIOLO, C WONG, HK WINSKE, D AF GURGIOLO, C WONG, HK WINSKE, D TI LOW AND HIGH-FREQUENCY WAVES GENERATED BY GYROPHASE BUNCHED IONS AT OBLIQUE SHOCKS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID EARTHS BOW SHOCK; DIFFUSE IONS; BEAM INSTABILITIES; SOLAR-WIND; UPSTREAM; SIMULATIONS; ASSOCIATION; EXCITATION; FORESHOCK; PARALLEL AB The interaction of the solar wind with gyrophase bunched ions reflected at an oblique (THETA(Bn) = 45-degrees) shock (M(A) = 8) is simulated using a 1D hybrid code. These ions are unstable to low frequency hydromagnetic waves as well as whistler waves. At some point in the hydromagnetic wave growth ion trapping occurs which restricts the local distribution in gyrophase to a higher degree than the input distribution. Given the growth rate of the MHD waves, gyrophase mixing is ineffective in isotropising the ions, except at the leading edge of the injected distribution. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP GURGIOLO, C (reprint author), SW RES INST,PO DRAWER 28510,SAN ANTONIO,TX 78228, USA. NR 19 TC 16 Z9 16 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 MAY 7 PY 1993 VL 20 IS 9 BP 783 EP 786 DI 10.1029/93GL00854 PG 4 WC Geosciences, Multidisciplinary SC Geology GA LC958 UT WOS:A1993LC95800005 ER PT J AU SCHWARZ, RB RUBIN, JB AF SCHWARZ, RB RUBIN, JB TI SOLID-STATE AMORPHIZING TRANSFORMATIONS - THERMODYNAMICS AND KINETICS SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT SYMP ON SOLID STATE AMORPHIZING TRANSFORMATIONS, AT THE 1991 FALL MEETING OF THE METALLURGICAL SOC OF THE AMERICAN INST OF MINING, METALLURGICAL AND PETROLEUM ENGINEERS CY OCT, 1991 CL CINCINNATI, OH SP AMER INST MIN MET & PETR ENGINEERS, MET SOC ID AMORPHOUS NI-ZR; METALLIC GLASSES; THIN-FILMS; ALLOY; CRYSTAL; DIFFUSION; SYSTEMS; NUCLEATION; DIAGRAM; LIQUID AB Amorphous metallic alloys are thermodynamically metastable with respect to one or more crystalline phases. Forming an amorphous alloy by an isothermal solid-state transformation requires starting from a state of free energy higher than that of the amorphous phase and choosing a reaction path that prevents the system from reaching the crystalline state of lowest free energy. Much has been learned about solid-state amorphizing transformations from interdiffusion experiments in transition-metal thin-film multilayers. We review some of these experiments and discuss recent advances in our understanding of the thermodynamics and kinetics of the phenomenon. RP SCHWARZ, RB (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,LOS ALAMOS,NM 87545, USA. NR 57 TC 15 Z9 15 U1 0 U2 5 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 MAY 7 PY 1993 VL 194 IS 2 BP 189 EP 197 DI 10.1016/0925-8388(93)90002-5 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA LC485 UT WOS:A1993LC48500002 ER PT J AU LIN, XW SEIDMAN, DN OKAMOTO, PR AF LIN, XW SEIDMAN, DN OKAMOTO, PR TI INSITU STUDIES OF AMORPHIZATION OF THE GE-AL AND SI-AL SYSTEMS INDUCED BY 1 MEV ELECTRON-IRRADIATION SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article ID DEFECTS; ALUMINUM; DIFFUSION; SILICON; ALLOY AB Ge-Al and Si-Al bilayer specimens, and also Al-2.3at.%Ge two-phase alloy specimens, were irradiated in situ with 1 MeV electrons at temperatures in the range 10-190 K in a high voltage electron microscope. The Ge precipitates in the Al-2.3at.%Ge alloy disappeared completely at a critical fluence (PHI(c)) of approximately 2.4 x 10(23) cm-2 (24 displacements per atom (dpa) in Ge and 14 dpa in Al) for specimens irradiated at 10 or 50 K; this is the same value of PHI(c) at which Ge-Al bilayers are found to contain an amorphous phase. At 10 K an irradiated Ge-Al bilayer specimen is found to have an amorphous phase at the interface only when a Ge layer faces the incident electron beam, while for a Si-Al bilayer specimen amorphization occurs at the interface independent of the direction of the incident beam with respect to a bilayer. For Ge-Al bilayer specimens PHI(c) is approximately 2.5 x 10(23) cm-2 (25 dpa in Ge and 15 dpa in Al). For Si-Al bilayers PHI(c) is approximately 3 x 10(23) cm-2 (19 dpa in Si and 18 dpa in Al). The temperature dependence of PHI(c) is also studied for a Ge-Al bilayer specimen. The value of PHI(c) is a constant for T < almost-equal-to 160 K, and then it increases rapidly with increasing T; PHI(c) becomes immeasurably large (more than 70 dpa in Ge and more than 43 dpa in Al) at a critical temperature of about 190 K. The temperature dependence of the crystalline to amorphous transition is explained in terms of a recoil-implantation mechanism, coupled with a radiation-enhanced monovacancy diffusion mechanism for Ge atoms in Al, and an athermal contribution to Ge diffusion in Al via an electron-beam stimulated monovacancy migration mechanism. C1 NORTHWESTERN UNIV,DEPT MAT SCI & ENGN,EVANSTON,IL 60208. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. NORTHWESTERN UNIV,ROBERT R MCCORMICK SCH ENGN & APPL SCI,MAT RES CTR,EVANSTON,IL 60208. RI Seidman, David/B-6697-2009 NR 44 TC 1 Z9 1 U1 0 U2 3 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 MAY 7 PY 1993 VL 194 IS 2 BP 389 EP 400 DI 10.1016/0925-8388(93)90024-H PG 12 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA LC485 UT WOS:A1993LC48500024 ER PT J AU WANG, JH YIP, S PHILLPOT, S WOLF, D AF WANG, JH YIP, S PHILLPOT, S WOLF, D TI INTRINSIC RESPONSE OF CRYSTALS TO PURE DILATATION SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT SYMP ON SOLID STATE AMORPHIZING TRANSFORMATIONS, AT THE 1991 FALL MEETING OF THE METALLURGICAL SOC OF THE AMERICAN INST OF MINING, METALLURGICAL AND PETROLEUM ENGINEERS CY OCT, 1991 CL CINCINNATI, OH SP AMER INST MIN MET & PETR ENGINEERS, MET SOC ID METALS; STATE AB The response of an f.c.c. lattice with Lennard-Jones interaction under symmetric lattice extension has been studied by Monte Carlo simulation at several temperatures. The critical strain at which the crystal undergoes a structural change is found to be well predicted by the mechanical stability limit expressed in terms of either the elastic constants or the bulk modulus. At low temperature (reduced temperature T=0.125), lattice decohesion is observed in the form of cleavage fracture, whereas at higher temperature (T=0.3) the strained system deforms by cavitation with some degree of local plasticity. At still higher temperature (T=0.5) the lattice undergoes homogeneous disordering with all the attendant characteristics of melting. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP WANG, JH (reprint author), MIT,DEPT NUCL ENGN,CAMBRIDGE,MA 02139, USA. RI Phillpot, Simon/J-9117-2012; OI Phillpot, Simon/0000-0002-7774-6535 NR 16 TC 10 Z9 10 U1 0 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 MAY 7 PY 1993 VL 194 IS 2 BP 407 EP 415 DI 10.1016/0925-8388(93)90026-J PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA LC485 UT WOS:A1993LC48500026 ER PT J AU LAM, NQ OKAMOTO, PR SABOCHICK, MJ DEVANATHAN, R AF LAM, NQ OKAMOTO, PR SABOCHICK, MJ DEVANATHAN, R TI RADIATION-INDUCED CRYSTALLINE-TO-AMORPHOUS TRANSITION IN INTERMETALLIC COMPOUNDS OF THE CU-TI ALLOY SYSTEM SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT SYMP ON SOLID STATE AMORPHIZING TRANSFORMATIONS, AT THE 1991 FALL MEETING OF THE METALLURGICAL SOC OF THE AMERICAN INST OF MINING, METALLURGICAL AND PETROLEUM ENGINEERS CY OCT, 1991 CL CINCINNATI, OH SP AMER INST MIN MET & PETR ENGINEERS, MET SOC ID EMBEDDED-ATOM METHOD; ELASTIC-CONSTANTS; INDUCED AMORPHIZATION; MOLECULAR-DYNAMICS; ELECTRON-IRRADIATION; MECHANICAL-PROPERTIES; ATOMISTIC SIMULATION; COMPUTER-SIMULATION; CHEMICAL DISORDER; METALLIC-GLASS AB Recent progress in molecular-dynamics studies of radiation-induced crystalline-to-amorphous transition in the ordered intermetallic compounds of the Cu-Ti system is discussed. The effect of irradiation was simulated by the generation of Frenkel pairs, which resulted in both the formation of stable point defects and chemical disorder upon defect recombination. The thermodynamic, structural and mechanical responses of the compounds during irradiation were determined by monitoring changes in the system potential energy, volume expansion, pair-correlation function, diffraction patterns, and elastic constants. It was found that the intermetallics Cu4Ti3, CuTi and CuTi2 could be rendered amorphous by the creation of Frenkel pairs, but Cu4Ti could not, consistent with experimental observations during electron irradiation. However, the simulations showed that Cu4Ti did become amorphous when clusters of Frenkel pairs were introduced, indicating that this compound may be susceptible to amorphization by heavy-ion bombardment. A generalization of the Lindemann criterion was used to develop a thermodynamic description of solid-state amorphization as a disorder-induced melting process. C1 GULF STATES UTIL CO,DIV COMP APPLICAT,BEAUMONT,TX 77704. RP LAM, NQ (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Devanathan, Ram/C-7247-2008 OI Devanathan, Ram/0000-0001-8125-4237 NR 47 TC 16 Z9 16 U1 2 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 MAY 7 PY 1993 VL 194 IS 2 BP 429 EP 437 DI 10.1016/0925-8388(93)90028-L PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA LC485 UT WOS:A1993LC48500028 ER PT J AU DEVANATHAN, R LAM, NQ OKAMOTO, PR SABOCHICK, MJ MESHII, M AF DEVANATHAN, R LAM, NQ OKAMOTO, PR SABOCHICK, MJ MESHII, M TI ATOMISTIC SIMULATION OF RADIATION-INDUCED AMORPHIZATION OF THE ORDERED COMPOUND NIZR SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article ID IRRADIATION INDUCED AMORPHIZATION; MOLECULAR-DYNAMICS; INTERMETALLIC COMPOUNDS; ELECTRON-IRRADIATION; BRILLOUIN-SCATTERING; ELASTIC-CONSTANTS; CRYSTALLINE; NITI; DISORDER; METALS AB We have investigated the electron-irradiation-induced amorphization of the ordered compound NiZr using molecular dynamics simulations. Ni and Zr atoms were randomly exchanged and Frenkel pairs were introduced, in two separate processes, to simulate the effects of electron irradiation. The interatomic potentials for the simulations were developed using the embedded-atom method. During the simulation, the state of the system was studied by monitoring changes in thermodynamic, mechanical and structural properties as functions of damage dose. Our results indicate that NiZr can be amorphized by atom exchanges as well as by the introduction of Frenkel pairs and are in agreement with experimental observations. C1 NORTHWESTERN UNIV,DEPT MAT SCI & ENGN,EVANSTON,IL 60208. GULF STATES UTIL CO,DIV COMP APPLICAT,BEAUMONT,TX 77704. RP DEVANATHAN, R (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Devanathan, Ram/C-7247-2008 OI Devanathan, Ram/0000-0001-8125-4237 NR 31 TC 21 Z9 21 U1 0 U2 4 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 MAY 7 PY 1993 VL 194 IS 2 BP 447 EP 454 DI 10.1016/0925-8388(93)90030-Q PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA LC485 UT WOS:A1993LC48500030 ER PT J AU JACOBSON, SC SEIDELMORGENSTERN, A GUIOCHON, G AF JACOBSON, SC SEIDELMORGENSTERN, A GUIOCHON, G TI STUDY OF BAND BROADENING IN ENANTIOSELECTIVE SEPARATIONS USING MICROCRYSTALLINE CELLULOSE TRIACETATE .1. THE LINEAR CASE SO JOURNAL OF CHROMATOGRAPHY LA English DT Article ID LIQUID-CHROMATOGRAPHIC SEPARATIONS; ENANTIOMERS; PRESSURE; PACKINGS AB Linear chromatographic data were obtained for the enantiomers of Troger's base separated on microcrystalline cellulose triacetate with pure ethanol as the mobile phase. The efficiency was determined for flow-rates between 0.1 and 1.0 ml/min at temperatures of 303, 318, 333 and 348 K. The efficiency is poor (below 100 plates) at 303 K, but increases rapidly with increasing temperature. From studies of the effects of these two parameters, the band profile dispersion is attributed to flow anisotropy and adsorption-desorption kinetics. The experimental elution profiles are compared with calculated profiles as a check on the quality of the efficiency measurements. C1 UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37831. TECH UNIV BERLIN,INST TECH CHEM,W-1000 BERLIN,GERMANY. NR 11 TC 17 Z9 18 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR PD MAY 7 PY 1993 VL 637 IS 1 BP 13 EP 18 DI 10.1016/0021-9673(93)83093-8 PG 6 WC Chemistry, Analytical SC Chemistry GA LB499 UT WOS:A1993LB49900002 ER PT J AU SEIDELMORGENSTERN, A JACOBSON, SC GUIOCHON, G AF SEIDELMORGENSTERN, A JACOBSON, SC GUIOCHON, G TI STUDY OF BAND BROADENING IN ENANTIOSELECTIVE SEPARATIONS USING MICROCRYSTALLINE CELLULOSE TRIACETATE .2. FRONTAL ANALYSIS SO JOURNAL OF CHROMATOGRAPHY LA English DT Article ID CHROMATOGRAPHY; SIMULATION AB Frontal analysis is classically used to measure adsorption isotherms, and in this work the isotherms of Troger's base were determined on microcrystalline cellulose triacetate with ethanol as solvent at 30, 40 and 50-degrees-C for the (-)-enantiomer and at 30-degrees-C for the (+)-enantiomer. The isotherms of the first eluted (-)-enantiomer are described satisfactorily by the Langmuir equation at all temperatures. ln contrast, the isotherm of the longer retained (+)-enantiomer possesses a pronounced inflection point and can be described by a quadratic isotherm equation. However, besides supplying information about the adsorption equilibrium, frontal analysis data can be used to determine kinetic parameters. Using the equilibrium-dispersive model of chromatography, the apparent axial dispersion coefficient was derived by fitting the breakthrough curve for each concentration step. The values are in general agreement with those obtained from the classical determination of the efficiency of elution profiles under linear conditions. However, the apparent dispersion coefficient determined from frontal analysis depends on the concentration. C1 UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. TECH UNIV BERLIN,INST TECH CHEM,W-1000 BERLIN,GERMANY. OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37831. OI Seidel-Morgenstern, Andreas/0000-0001-8595-7810 NR 17 TC 37 Z9 37 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR PD MAY 7 PY 1993 VL 637 IS 1 BP 19 EP 28 DI 10.1016/0021-9673(93)83094-9 PG 10 WC Chemistry, Analytical SC Chemistry GA LB499 UT WOS:A1993LB49900003 ER PT J AU TRILLING, GH AF TRILLING, GH TI SUPPORT FOR THE SSC SO SCIENCE LA English DT Letter C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP TRILLING, GH (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD MAY 7 PY 1993 VL 260 IS 5109 BP 737 EP 738 DI 10.1126/science.260.5109.737 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA LA744 UT WOS:A1993LA74400002 PM 17746099 ER PT J AU KINNEY, JH BREUNIG, TM STARR, TL HAUPT, D NICHOLS, MC STOCK, SR BUTTS, MD SAROYAN, RA AF KINNEY, JH BREUNIG, TM STARR, TL HAUPT, D NICHOLS, MC STOCK, SR BUTTS, MD SAROYAN, RA TI X-RAY TOMOGRAPHIC STUDY OF CHEMICAL VAPOR INFILTRATION PROCESSING OF CERAMIC COMPOSITES SO SCIENCE LA English DT Article AB The fabrication of improved ceramic-matrix composites will require a better understanding of processing variables and how they control the development of the composite microstructure. Noninvasive, high-resolution methods of x-ray tomography have been used to measure the growth of silicon carbide in a woven Nicalon-fiber composite during chemical vapor infiltration. The high spatial resolution allows one to measure the densification within individual fiber tows and to follow the closure of macroscopic pores in situ. The experiments provide a direct test of a recently proposed model that describes how the surface area available for matrix deposition changes during infiltration. The measurements indicate that this surface area is independent of the fiber architecture and location within the preform and is dominated by large-scale macroporosity during the final stages of composite consolidation. The measured surface areas are in good agreement with the theoretical model. C1 SANDIA NATL LABS,LIVERMORE,CA 94550. GEORGIA INST TECHNOL,ATLANTA,GA 30332. RP KINNEY, JH (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551, USA. NR 12 TC 56 Z9 58 U1 1 U2 7 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD MAY 7 PY 1993 VL 260 IS 5109 BP 789 EP 792 DI 10.1126/science.260.5109.789 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA LA744 UT WOS:A1993LA74400024 PM 17746112 ER PT J AU MUKERJI, I SAUER, K AF MUKERJI, I SAUER, K TI ENERGY-TRANSFER DYNAMICS OF AN ISOLATED LIGHT-HARVESTING COMPLEX OF PHOTOSYSTEM-I FROM SPINACH - TIME-RESOLVED FLUORESCENCE MEASUREMENTS AT 295-K AND 77-K SO BIOCHIMICA ET BIOPHYSICA ACTA LA English DT Article DE CHLOROPHYLL; ENERGY TRANSFER; FLUORESCENCE; LIGHT HARVESTING COMPLEX-I; PHOTOSYSTEM-I ID CHLOROPHYLL-PROTEIN COMPLEXES; ANTENNA EXCITATION TRANSPORT; PUMP-PROBE SPECTROSCOPY; CHLAMYDOMONAS-REINHARDTII; RESOLUTION; BIOGENESIS AB Time-resolved fluorescence relaxation measurements have been performed at 295 K and 77 K on a preparation of the light-harvesting complex of Photosystem I (LHCI) containing about 100 chlorophylls (Chl) per complex. At both temperatures five exponential components were required to fit the data. The resulting determined lifetimes are 30 ps, 200 ps, 1.0 ns, 3.3 ns and 6.5 ns. Previous steady-state fluorescence measurements demonstrated that the emission at 735 nm increases dramatically upon cooling to 77 K. Time-resolved fluorescence measurements performed at 77 K reveal the presence of two risetimes for emission between 700 and 750 nm. These results are consistent with an efficient trap for electronic excitation existing at longer wavelengths than the absorption maximum of P700, the reaction center of Photosystem I (PS I). Excitation of Chl b results in a relative amplitude enhancement of decay components emitting between 720 and 750 nm. This confirms that Chl b is specifically associated with long wavelength emitters in Photosystem I. C1 LAWRENCE BERKELEY LAB,DEPT CHEM,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV STRUCT BIOL,BERKELEY,CA 94720. NR 35 TC 33 Z9 34 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0006-3002 J9 BIOCHIM BIOPHYS ACTA PD MAY 6 PY 1993 VL 1142 IS 3 BP 311 EP 320 DI 10.1016/0005-2728(93)90159-D PG 10 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA LB413 UT WOS:A1993LB41300010 ER PT J AU RODRIGUEZ, JA HRBEK, J KUHN, M SHAM, TK AF RODRIGUEZ, JA HRBEK, J KUHN, M SHAM, TK TI INTERACTION OF O-2 WITH LI-AU AND CS-AU FILMS - A PHOTOEMISSION AND THERMAL-DESORPTION STUDY SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID ELECTRONIC-STRUCTURE; OXYGEN; RU(001); COADSORPTION; ADSORPTION; POTASSIUM; CESIUM; METALS; GOLD AB The reaction of O2 with thick Li-Au or Cs-Au films supported on Ru(001) has been investigated using thermal desorption mass spectroscopy and core- and valence-level photoemission. The interaction of O2 with CsAu at 100 K produces O2(2-) (the only oxygen species at low O2 exposures) and O2-. Annealing of the O2/CsAu film to 300 K leads to the disappearance of O2- and the appearance of O2 . The adsorption of O2 on Li-Au alloys at 300 K produces the O2- ion together with another oxygen species. The presence of oxygen shifts the Au(4f) and Cs(3d) levels of CsAu approximately 1 eV toward lower binding energy, with the final peak positions being very close to those observed for metallic Au and oxidized Cs. A similar result was observed for O2/Li-Au. No evidence for bonding between the oxygen ions and Au was found. At T less-than-or-equal-to 300 K, oxygen breaks the Au-alkali bonds to form Li.O or Cs.O and very small Au clusters that are dispersed on the film. Annealing to 500 K produces sintering of these Au clusters into large three-dimensional particles. The existence of Li-O or Cs-O bonds increases the thermal stability of the alkali in the film. The Li.O and Cs.O compounds decompose at much higher temperatures than the LiAu and CsAu alloys. C1 UNIV WESTERN ONTARIO,DEPT CHEM,LONDON N6A 5B7,ONTARIO,CANADA. RP RODRIGUEZ, JA (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. RI Hrbek, Jan/I-1020-2013 NR 31 TC 11 Z9 11 U1 0 U2 1 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 MAY 6 PY 1993 VL 97 IS 18 BP 4737 EP 4744 DI 10.1021/j100120a029 PG 8 WC Chemistry, Physical SC Chemistry GA LA766 UT WOS:A1993LA76600029 ER PT J AU HOFFERT, MI COVEY, C AF HOFFERT, MI COVEY, C TI PALEOCLIMATE SENSITIVITY - REPLY SO NATURE LA English DT Letter ID CLIMATE MODEL; ICE; GROWTH C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP HOFFERT, MI (reprint author), NYU,DEPT APPL SCI,EARTH SYST GRP,NEW YORK,NY 10003, USA. NR 19 TC 0 Z9 0 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD MAY 6 PY 1993 VL 363 IS 6424 BP 26 EP 26 DI 10.1038/363026a0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA LA682 UT WOS:A1993LA68200042 ER PT J AU BEATTY, DP GILMAN, R SUN, Q FORTUNE, HT WILLIAMS, AL SMITH, DA HUI, P LOE, S LANDAU, MA ODONNELL, JM RAWOOLSULLIVAN, M URBINA, J WATSON, DL AF BEATTY, DP GILMAN, R SUN, Q FORTUNE, HT WILLIAMS, AL SMITH, DA HUI, P LOE, S LANDAU, MA ODONNELL, JM RAWOOLSULLIVAN, M URBINA, J WATSON, DL TI PION DOUBLE CHARGE-EXCHANGE ON O-16 ABOVE THE DELTA(1232) RESONANCE SO PHYSICS LETTERS B LA English DT Article ID ANGULAR-DISTRIBUTIONS; O-16(PI+,PI-)NE-16(GS); INTERFERENCE; SCATTERING AB Measurements of cross sections for pion double charge exchange (DCX) on O-16 at incident pion energies of 180-292 MeV and laboratory scattering angles of 5-degrees-35-degrees have been obtained using EPICS at LAMPF. The angular distributions indicate a shift in the position of the first minimum from that expected for diffractive scattering as a function of energy. C1 UNIV PENN,PHILADELPHIA,PA 19104. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. NEW MEXICO STATE UNIV,LAS CRUCES,NM 88003. UNIV YORK,YORK YO1 5DD,N YORKSHIRE,ENGLAND. RP BEATTY, DP (reprint author), RUTGERS UNIV,PISCATAWAY,NJ 08855, USA. NR 19 TC 3 Z9 3 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 MAY 6 PY 1993 VL 305 IS 1-2 BP 13 EP 17 DI 10.1016/0370-2693(93)91098-8 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA087 UT WOS:A1993LA08700004 ER PT J AU OZKUL, MH MARK, JE AUBERT, JH AF OZKUL, MH MARK, JE AUBERT, JH TI THE ELASTIC AND PLASTIC MECHANICAL RESPONSES OF MICROCELLULAR FOAMS SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article ID LOW-DENSITY AB Microcellular foams were prepared by the thermally induced phase-separation technique, which yields materials having very small cell dimensions (0.1-20 mum). The polymers employed were isotactic polystyrene, polyacrylonitrile, poly(4-methyl-1-pentene), polyurethane, and Lycra(R) and the resulting foams all had densities in the range 0.04-0.27 g cm-3. Values of Young's modulus and the collapse stress for these foams were measured and compared with predictions for conventional foams containing defects. Also investigated were plastic deformations, some time-dependent behavior, and Poisson's ratio. C1 UNIV CINCINNATI,DEPT CHEM,CINCINNATI,OH 45221. TECH UNIV ISTANBUL,FAC CIVIL ENGN,ISTANBUL 80626,TURKEY. UNIV CINCINNATI,POLYMER RES CTR,CINCINNATI,OH 45221. SANDIA NATL LABS,DIV 1813,ALBUQUERQUE,NM 87185. NR 17 TC 9 Z9 10 U1 0 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD MAY 5 PY 1993 VL 48 IS 5 BP 767 EP 774 DI 10.1002/app.1993.070480502 PG 8 WC Polymer Science SC Polymer Science GA KX500 UT WOS:A1993KX50000002 ER PT J AU YEH, JI BIEMANN, HP PANDIT, J KOSHLAND, DE KIM, SH AF YEH, JI BIEMANN, HP PANDIT, J KOSHLAND, DE KIM, SH TI THE 3-DIMENSIONAL STRUCTURE OF THE LIGAND-BINDING DOMAIN OF A WILD-TYPE BACTERIAL CHEMOTAXIS RECEPTOR - STRUCTURAL COMPARISON TO THE CROSS-LINKED MUTANT FORMS AND CONFORMATIONAL-CHANGES UPON LIGAND-BINDING SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID ASPARTATE RECEPTOR; SENSORY RECEPTOR; CRYSTALLIZATION AB The three-dimensional structures of the ligand-binding domain of the wild-type Salmonella typhimurium aspartate receptor have been determined in the absence (apo) and presence of bound aspartate (complex) and compared to a cross-linked mutant containing a cysteine at position 36 which does not change signaling behavior of the intact receptor. The structures of the wild-type forms were determined in order to assess the effects of cross-linking on the structure and its influence on conformational changes upon ligand binding. As in the case of the cross-linked mutant receptor, the non-cross-linked ligand-binding domain is dimeric and is composed of 4-alpha-helical bundle monomer subunits related by a crystallographic 2-fold axis in the unbound form and by a non-crystallographic axis in the aspartate-bound form. A comparative study between the non-cross-linked and cross-linked structures has led to the following observations: 1) The long N-terminal helices of the individual subunits in the cross-linked structures are bent toward each other to accommodate the disulfide bond. 2) The rest of the subunit conformation is very similar to that of the wild-type. 3) The intersubunit angle of the cross-linked apo structure is larger by about 13 degrees when compared to the wild-type apo structure. 4) The nature and magnitude of the aspartate-induced conformational changes in the non-crosslinked wild-type structures are very similar to those of the cross-linked structures. C1 LAWRENCE BERKELEY LAB,DEPT MOLEC & CELL BIOL,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV STRUCT BIOL,BERKELEY,CA 94720. RP YEH, JI (reprint author), LAWRENCE BERKELEY LAB,DEPT CHEM,BERKELEY,CA 94720, USA. FU NIAID NIH HHS [AI 30725]; NIDDK NIH HHS [DK09765]; NIGMS NIH HHS [T32 GM08295-04] NR 13 TC 85 Z9 86 U1 1 U2 1 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 MAY 5 PY 1993 VL 268 IS 13 BP 9787 EP 9792 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA LA689 UT WOS:A1993LA68900092 PM 8486661 ER PT J AU BARKIGIA, KM RENNER, MW FURENLID, LR MEDFORTH, CJ SMITH, KM FAJER, J AF BARKIGIA, KM RENNER, MW FURENLID, LR MEDFORTH, CJ SMITH, KM FAJER, J TI CRYSTALLOGRAPHIC AND EXAFS STUDIES OF CONFORMATIONALLY DESIGNED NONPLANAR NICKEL(II) PORPHYRINS SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID DIFFERENTIAL-OVERLAP TECHNIQUE; LIGHT-ABSORPTION PROPERTIES; MOLECULAR-STRUCTURE; PHOTOSYNTHETIC CHROMOPHORES; INTERMEDIATE NEGLECT; FINE-STRUCTURE; MODELS; CRYSTAL; CONSEQUENCES; SPECTROSCOPY AB A series of Ni(II) tetraphenylporphyrins with varying beta substituents was examined by X-ray crystallography and EXAFS to assess peripheral steric effects on the conformations of the macrocycles. The compounds are the low-spin Ni(II) derivatives of 2,3,7,8,12,13,17,18-octaethyl-5,10,15,20-tetraphenylporphyrin (1), 2,3,7,8,12,13,17-18-octapropyl-5,10,15,20-tetrapbenylporphyrin (2), 2,3,7,8,12,13,17,18-tetracyclohexenyl-5,10,15,20-tetraphenylporphyrin (3), 2,3,5,7,8,10,12,13,15,17,18,20-dodecaphenylporphyrin (4), 2,3,7,8,12,13,17,18-tetracyclopentenyl-5,10,15,20-tetraphenylprophyrin (5), and 2,3,7,8,12,13,17,18-tetracyclopentenyl-5,10,15,20-tetrakis(3,4,5-trimethoxyphenyl)porphyrin (6). X-ray structures of 1, 2, and 3 reveal that the molecules are severely nonplanar and assume saddle shapes in which the pyrrole rings lie alternately above and below the porphyrin planes with beta carbon displacements of more than 1 angstrom while the meso carbons remain in plane. 1 crystallizes with three methanols of solvation per porphyrin that form an unusual infinite hydrogen-bonded methanol network that transverses one axis of the crystal. Advantage is taken of the fact that short and long Ni-N distances are diagnostic of ruffled and planar Ni macrocycles, respectively, to establish the conformations of the molecules in solution and in the amorphous state by EXAFS. Within the precision of the EXAFS data (0.02 angstrom), the Ni-N distances in 1, 2, and 3 are the same in solution and in amorphous powders as in the crystals and establish therefore that the distorted conformations of the compounds are maintained in all three phases. EXAFS data for 4, whose structure is unknown, indicate an equally distorted geometry in solution and in the powder. In contrast to 1-4, EXAFS results for 5 and 6 as powders, and for 6 in solution, clearly signal planar conformations for the two tetracyclopentenyl derivatives. Further evidence that 6 is not sterically constrained derives from the observation that it can be converted to a high-spin hexacoordinated Ni(II) complex in pyridine (5 is insoluble). The conformations and Ni-N distances obtained crystallographically or by EXAFS for 1-6 agree well with previous molecular mechanics calculations. The macrocycle distortions induce optical red shifts attributed to a smaller gap between the HOMOs and LUMOs of the porphyrins. In particular, the first optical transition, which is principally a HOMO to LUMO excitation, is correctly predicted by INDO/s calculations based on the crystal coordinates for 1, 2, and 3 reported here. An additional assessment of the effects of the substituents and macrocycle conformations on the frontier orbitals of the molecules is obtained from cyclic voltammetry measurements of oxidation and reduction potentials which provide an experimental probe of the migration of the HOMOs and LUMOs; the electrochemically determined differences in redox potentials mirror the first optical transitions. Crystallographic data: NiN4C60H60.3CH3OH (1): triclinic space group P1BAR, a = 13.739(1) angstrom, b = 17.055(4) angstrom, c = 12.938(2) angstrom, alpha = 96.89(1)degrees, beta = 107.66(1)degrees, gamma = 104.58(2)degrees, V = 2731.7 angstrom3, Z = 2, R(F) =0.066 and R(wF) = 0.091 based on 8077 reflections with F(o) > 6sigmaF(o). NiN4C68H76 (2): monoclinic space group P2(1)/n, a = 15.195(8) angstrom, b = 19.577(9) angstrom, c = 19.137(5) angstrom, beta = 98. 77(3)degrees, V = 5626.2 angstrom3, Z = 4, R(F) = 0.054 and R(wF) = 0.060 based on 5716 reflections with F(o) > 3sigmaF(o). NiN4C60H52.CH2Cl2 (3): tetragonal space group I4BAR, a = b = 32.111(11) angstrom, c = 9.876(8) angstrom, V = 10183 angstrom3, Z = 8, R(F) = 0.081 and R(wF) = 0.108 based on 3161 reflections with F(o) > 2sigmaF(o). T = 200 K. C1 BROOKHAVEN NATL LAB,DEPT SURG 1,UPTON,NY 11973. BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973. UNIV CALIF DAVIS,DEPT CHEM,DAVIS,CA 95616. RI Medforth, Craig/D-8210-2013; REQUIMTE, FMN/M-5611-2013; REQUIMTE, UCIBIO/N-9846-2013; Smith, Kevin/G-1453-2011 OI Medforth, Craig/0000-0003-3046-4909; Smith, Kevin/0000-0002-6736-4779 NR 60 TC 194 Z9 194 U1 4 U2 26 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 MAY 5 PY 1993 VL 115 IS 9 BP 3627 EP 3635 DI 10.1021/ja00062a029 PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA LA678 UT WOS:A1993LA67800029 ER PT J AU ZHANG, D CLOSS, GL CHUNG, DD NORRIS, JR AF ZHANG, D CLOSS, GL CHUNG, DD NORRIS, JR TI FREE-ENERGY AND ENTROPY CHANGES IN VERTICAL AND NONVERTICAL TRIPLET ENERGY-TRANSFER PROCESSES BETWEEN RIGID AND NONRIGID MOLECULES - A LASER PHOTOLYSIS STUDY SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TEMPERATURE HEAT-CAPACITIES; ELECTRON-TRANSFER REACTIONS; PULSE-RADIOLYSIS; RADICAL-ANIONS; BIPHENYL; STATE; BENZOPHENONE; SPECTROSCOPY; EQUILIBRIA; CRYSTALS AB The free energy and entropy changes associated with intermolecular triplet energy transfer (TT) processes were determined by direct measurement of the equilibrium constant using a laser flash photolysis technique. 10,10-Dimethylanthrone and 9,9-dimethylfluorene were synthesized and used as a 'rigid' donor and acceptor, respectively, in comparison with 4-methylbenzophenone, a ''nonrigid'' donor, and 4-methylbiphenyl, a ''nonrigid'' acceptor, in the TT reactions. Both the nonrigid donor and the nonrigid acceptor lose entropy while going from the twisted ground state to the planar triplet state. The DELTAS values for 4-methylbenzophenone and 4-methylbiphenyl are 0.5-1.0 and 2.5-3.0 gibbs/mol, respectively. C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. RP ZHANG, D (reprint author), UNIV CHICAGO,DEPT CHEM,CHICAGO,IL 60637, USA. NR 45 TC 10 Z9 10 U1 1 U2 5 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 MAY 5 PY 1993 VL 115 IS 9 BP 3670 EP 3673 DI 10.1021/ja00062a036 PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA LA678 UT WOS:A1993LA67800036 ER PT J AU MILLER, GJ LI, F FRANZEN, HF AF MILLER, GJ LI, F FRANZEN, HF TI THE STRUCTURAL PHASE-TRANSITION IN CAAL4 - A CONCERTED APPLICATION OF LANDAU THEORY AND ENERGY-BAND THEORY SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID INTERMETALLIC COMPOUNDS; CHEMISTRY; ALUMINUM; BAAL4 AB CaAl4 undergoes a reversible, structural transformation at 170-degrees-C according to high-temperature X-ray powder diffraction experiments. The high-temperature phase adopts the tetragonal BaAl4 structure (space group I4/mmm), while the low-temperature phase is monoclinic, C2/m, with lattice parameters, a = 6.1526 (15) angstrom, b = 6.1730 (13) angstrom, c = 6.3290 (14) angstrom, beta = 118.026 (16)degrees. The Landau theory of phase transitions correctly provided a structural model for the low-temperature phase, which could be subsequently refined. Also, electronic structure calculations on both forms of CaAl4 allow rationalization of the transformation in terms of changes in local chemical bonding within the Al framework. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. RP MILLER, GJ (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES,IA 50011, USA. NR 29 TC 20 Z9 20 U1 0 U2 5 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 MAY 5 PY 1993 VL 115 IS 9 BP 3739 EP 3745 DI 10.1021/ja00062a045 PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA LA678 UT WOS:A1993LA67800045 ER PT J AU SNYDER, SW MORRIS, AL BONDESON, SR NORRIS, JR THURNAUER, MC AF SNYDER, SW MORRIS, AL BONDESON, SR NORRIS, JR THURNAUER, MC TI ELECTRON-SPIN POLARIZATION IN SEQUENTIAL ELECTRON-TRANSFER - AN EXAMPLE FROM IRON-CONTAINING PHOTOSYNTHETIC BACTERIAL REACTION CENTER PROTEINS SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Note ID RHODOBACTER-SPHAEROIDES R-26; PARAMAGNETIC RESONANCE-SPECTRA; RHODOPSEUDOMONAS-SPHAEROIDES; ACCEPTOR COMPLEX; RADICAL PAIRS; H-SUBUNIT; TEMPERATURE; MODEL; DEPENDENCE; FE2+ C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. UNIV CHICAGO,DEPT CHEM,CHICAGO,IL 60637. RI Snyder, Seth/C-4370-2008 OI Snyder, Seth/0000-0001-6232-1668 NR 46 TC 18 Z9 19 U1 0 U2 0 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 MAY 5 PY 1993 VL 115 IS 9 BP 3774 EP 3775 DI 10.1021/ja00062a053 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA LA678 UT WOS:A1993LA67800053 ER PT J AU LIN, JB PANG, Y YOUNG, VG BARTON, TJ AF LIN, JB PANG, Y YOUNG, VG BARTON, TJ TI SYNTHESIS AND STRUCTURE OF STRAINED, CYCLIC BISALLENES SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Note C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 8 TC 20 Z9 20 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAY 5 PY 1993 VL 115 IS 9 BP 3794 EP 3795 DI 10.1021/ja00062a063 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA LA678 UT WOS:A1993LA67800063 ER PT J AU ALBUYARON, A FRANK, A NOUFI, R AF ALBUYARON, A FRANK, A NOUFI, R TI CROSS-SECTIONAL TRANSMISSION ELECTRON-MICROSCOPY OF THIN-FILM POLYCRYSTALLINE SEMICONDUCTORS BY CONVENTIONAL MICROTOMY SO THIN SOLID FILMS LA English DT Article ID ULTRAMICROTOMY; SPECIMENS AB Conventional ultramicrotomy with a glass knife is shown to be a valuable technique for studying thin film polycrystalline semiconductor materials in cross-section. High quality sections of CuInSe2 (CIS) polycrystalline thin films and of nanocrystalline PbSe films deposited on mica, suitable for electron microscopic investigations, can be obtained in large quantities within a very short time. Detailed cross-sectional transmission electron microscopy (XTEM) studies performed on CIS films revealed columnar grains of tetragonal chalcopyrite structure that nucleate at the CIS-mica interface. The average grain diameter is about 30-60 nm and increases with increasing distance from the substrate. Intergranular voids predominantly located near the interface were commonly observed. Microtwins on (112) planes were found in many of the grains. No second phases were observed in these samples. XTEM on nanocrystalline PbSe layers on mica revealed films made up of very small spherical grains (4-5 nm in diameter) of cubic PbSe dispersed in an amorphous matrix and uniformly distributed throughout the thickness of the layer. C1 WEIZMANN INST SCI,IL-76100 REHOVOT,ISRAEL. NATL RENEWABLE ENERGY LAB,GOLDEN,CO. RP ALBUYARON, A (reprint author), ARO,VOLCANI CTR,POB 6,IL-50250 BET DAGAN,ISRAEL. NR 12 TC 4 Z9 4 U1 1 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 MAY 5 PY 1993 VL 227 IS 1 BP 18 EP 23 DI 10.1016/0040-6090(93)90181-N PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA LD592 UT WOS:A1993LD59200005 ER PT J AU TIEDE, DM VASHISHTA, AC GUNNER, MR AF TIEDE, DM VASHISHTA, AC GUNNER, MR TI ELECTRON-TRANSFER KINETICS AND ELECTROSTATIC PROPERTIES OF THE RHODOBACTER-SPHAEROIDES REACTION CENTER AND SOLUBLE C-CYTOCHROMES SO BIOCHEMISTRY LA English DT Article ID PHOTOSYNTHETIC REACTION CENTER; RESOLUTION 3-DIMENSIONAL STRUCTURE; REACTION CENTER PROTEIN; HEME CREVICE DOMAIN; X-RAY-DIFFRACTION; RHODOPSEUDOMONAS-VIRIDIS; RHODOSPIRILLUM-RUBRUM; YEAST ISO-1-CYTOCHROME-C; MOLECULAR-DYNAMICS; TRANSFER COMPLEXES AB The kinetics of electron transfer between the Rhodobacter sphaeroides R-26 reaction center and nine soluble c-cytochromes have been analyzed and compared to the patterns of the surface electrostatic potentials for each of the proteins. Characteristic first-order electron-transfer rates for 1:1 complexes formed at low ionic strength between the reaction center and the different c-cytochromes were identified and found to vary by a factor of almost 100, while second-order rates were found to differ by greater than 10(6). A correlation was found between the location of likely electrostatic interaction domains on each cytochrome and its characteristic rate of electron transfer. The interaction domains were identified by mapping electrostatic potentials, calculated from the Poisson-Boltzmann equation, onto simulated ''encounter surfaces'' for each of the cytochromes and the reaction center. For the reaction center, the c-cytochrome binding domain was found to have almost exclusively net negative potential (<-3 kT) and to be shifted slightly toward the M-subunit side of the reaction center. The location of interaction domains of complementary, positive potential (>3 kT) differed for each cytochrome. The correspondence between electrostatic, structural, and kinetic properties of 1:1 reaction center-cytochrome complexes leads to a proposed mechanism for formation of reaction center-cytochrome electron-transfer complexes that is primarily driven by the juxtaposition of regions of delocalized complementary potential. In this mechanism the clustering of charged residues is of primary importance and not the location of specific residues. A consequence of this mechanism is that many different sets of charge distributions are predicted to be capable of stabilizing a specific configuration for a reaction center-cytochrome complex. This mechanism for reaction center association with water-soluble c-cytochromes fits molecular recognition mechanisms proposed for c-cytochromes in nonphotosynthetic systems. In general, the kinetic scheme for reaction center driven cytochrome oxidation was found to vary between a simple two-state model, involving cytochrome in free and reaction center bound states, and a three-state model, that includes cytochrome binding in kinetically competent(''proximal'')and incompetent (''distal'') modes. The kinetically incompetent mode of cytochrome binding is suggested not to be an intrinsic feature of the reaction center-cytochrome association but is likely to be due to variation in the physical state of the reaction center. C1 CUNY CITY COLL, DEPT PHYS, NEW YORK, NY 10031 USA. RP TIEDE, DM (reprint author), ARGONNE NATL LAB, DIV CHEM, ARGONNE, IL 60439 USA. NR 77 TC 108 Z9 110 U1 1 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD MAY 4 PY 1993 VL 32 IS 17 BP 4515 EP 4531 DI 10.1021/bi00068a006 PG 17 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA LA560 UT WOS:A1993LA56000006 PM 8387335 ER PT J AU DUAN, ZB HAMPDENSMITH, MJ SYLWESTER, AP AF DUAN, ZB HAMPDENSMITH, MJ SYLWESTER, AP TI STUDIES OF THE THERMAL AND PHOTOCHEMICAL LABILITY OF OLEFIN COMPLEXES OF RHODIUM(I) TO FORM RH AND RH2O3 SO JOURNAL OF ORGANOMETALLIC CHEMISTRY LA English DT Article ID METAL; CATALYSTS AB Thermogravimetric analyses of the series of compounds [L2RhCl]2, where L2 = 1,5-COD, NBD and (C2H4)2 under air, nitrogen and 7%H-2 in N2 atmospheres reveal that thermal decomposition behavior depends on the nature of the olefin ligand and the composition of the atmosphere. Under a 7% H-2 in N2 atmosphere, the onset of thermal decomposition of these species occurs in the following order: L2 = (C2H4)2, 91-degrees-C; NBD, 143-degrees-C; 1,5-COD, 212-degrees-C. Under a nitrogen atmosphere, [L2RhCl]2, L2 = NBD and (C2H4)2, undergo weight loss consistent with loss of one or more olefin ligands, then formation of Rh metal at higher temperatures. In contrast, [(1,5-COD)RhCl]2 formed Rh metal directly. In air, thermal decomposition generally resulted in formation of crystalline Rh metal followed by oxidation above 500-degrees-C to form crystalline Rh2O3, except for [(C2H4)2RhCl]2, which gave Rh2O3 directly. The Rh and Rh2O3 powders were analyzed by powder X-ray diffraction. In some experiments, a weight loss consistent with formation of ''RhCl'' was observed. However, as a result of the crystalline Rh present, it is proposed that disproportionation to Rh and RhCl3 may have occurred. The compound [(C2H4)2Rh(OEt)]2 . H2O is photolabile and undergoes decomposition on exposure to UV radiation to give crystalline, 2 nm sized Rh metal particles as determined by TEM, EDS and electron diffraction. C1 UNIV NEW MEXICO, DEPT CHEM, ALBUQUERQUE, NM 87131 USA. UNIV NEW MEXICO, CTR MICROENGINEERED CERAM, ALBUQUERQUE, NM 87131 USA. SANDIA NATL LABS, DEPT 6211, ALBUQUERQUE, NM 87185 USA. NR 26 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-328X EI 1872-8561 J9 J ORGANOMET CHEM JI J. Organomet. Chem. PD MAY 4 PY 1993 VL 449 IS 1-2 BP 173 EP 180 DI 10.1016/0022-328X(93)80121-Q PG 8 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA LD055 UT WOS:A1993LD05500022 ER PT J AU LYDEARD, C AF LYDEARD, C TI PHYLOGENETIC ANALYSIS OF SPECIES RICHNESS - HAS VIVIPARITY INCREASED THE DIVERSIFICATION OF ACTINOPTERYGIAN FISHES SO COPEIA LA English DT Note ID EVOLUTION C1 AUBURN UNIV,DEPT ZOOL & WILDLIFE SCI,AUBURN,AL 36849. RP LYDEARD, C (reprint author), SAVANNAH RIVER ECOL LAB,DRAWER E,AIKEN,SC 29802, USA. NR 36 TC 9 Z9 9 U1 0 U2 3 PU AMER SOC ICHTHYOLOGISTS HERPETOLOGISTS BUSINESS OFFICE PI CARBONDALE PA SOUTHERN ILLINOIS UNIV, DEPT ZOOLOGY, CARBONDALE, IL 62901-6501 SN 0045-8511 J9 COPEIA JI Copeia PD MAY 3 PY 1993 IS 2 BP 514 EP 518 PG 5 WC Zoology SC Zoology GA LA729 UT WOS:A1993LA72900025 ER PT J AU HALL, LJ SARID, U AF HALL, LJ SARID, U TI GRAVITATIONAL SMEARING OF MINIMAL SUPERSYMMETRIC UNIFICATION PREDICTIONS SO PHYSICAL REVIEW LETTERS LA English DT Article ID GRAND UNIFIED THEORIES; KINETIC-ENERGY TERMS; ELECTROWEAK; SU(5); SCALE AB The prediction for alpha(s) in the minimal supersymmetric SU(5) grand unified theory is generically subject to uncertainties arising from a gravitationally induced dimension-five operator. Unless the coefficient of this operator is small, the correlation between alpha(s) and the mass scale which governs proton decay to Knu is destroyed. Furthermore, a reduction of the experimental uncertainty in alpha(s) would not provide a significant test of the theory. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. RP HALL, LJ (reprint author), LAWRENCE BERKELEY LAB,THEORET PHYS GRP,50A-3115,BERKELEY,CA 94720, USA. NR 29 TC 61 Z9 61 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 MAY 3 PY 1993 VL 70 IS 18 BP 2673 EP 2676 DI 10.1103/PhysRevLett.70.2673 PG 4 WC Physics, Multidisciplinary SC Physics GA KZ989 UT WOS:A1993KZ98900004 ER PT J AU BERN, Z DIXON, L KOSOWER, DA AF BERN, Z DIXON, L KOSOWER, DA TI ONE-LOOP CORRECTIONS TO 5-GLUON AMPLITUDES SO PHYSICAL REVIEW LETTERS LA English DT Article ID GAUGE-THEORIES; MULTIPLE BREMSSTRAHLUNG; GLUON SCATTERING AB We present the one-loop helicity amplitudes with five external gluons. The computation employs string-based methods, new techniques for performing tensor integrals, and improvements in the spinor helicity method. C1 STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. CERN,DIV THEORY,CH-1211 GENEVA 23,SWITZERLAND. RP BERN, Z (reprint author), UNIV CALIF LOS ANGELES,DEPT PHYS,LOS ANGELES,CA 90024, USA. NR 25 TC 228 Z9 228 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 MAY 3 PY 1993 VL 70 IS 18 BP 2677 EP 2680 DI 10.1103/PhysRevLett.70.2677 PG 4 WC Physics, Multidisciplinary SC Physics GA KZ989 UT WOS:A1993KZ98900005 ER PT J AU FALLON, P BURDE, J CEDERWALL, B DELEPLANQUE, MA DIAMOND, RM LEE, IY OLIVEIRA, JRB STEPHENS, FS BECKER, JA BRINKMAN, MJ HENRY, EA KUHNERT, A STOYER, MA DRAPER, JE DUYAR, C RUBEL, E AF FALLON, P BURDE, J CEDERWALL, B DELEPLANQUE, MA DIAMOND, RM LEE, IY OLIVEIRA, JRB STEPHENS, FS BECKER, JA BRINKMAN, MJ HENRY, EA KUHNERT, A STOYER, MA DRAPER, JE DUYAR, C RUBEL, E TI EVIDENCE FOR M1 TRANSITIONS BETWEEN SUPERDEFORMED STATES IN HG-193 SO PHYSICAL REVIEW LETTERS LA English DT Article ID OCTUPOLE CORRELATIONS; NUCLEI; BAND; DY-152 AB Two-way decay has been observed between superdeformed bands in Hg193. it is proposed the decays have M 1 multipolarity and connect signature partner bands. Candidates for the two-way gamma decays connecting superdeformed bands are observed for the first time. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. UNIV CALIF DAVIS,DAVIS,CA 95616. RP FALLON, P (reprint author), LAWRENCE BERKELEY LAB,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. RI Oliveira, Jose Roberto/J-3124-2012; Cederwall, Bo/M-3337-2014 OI Oliveira, Jose Roberto/0000-0003-1362-7382; Cederwall, Bo/0000-0003-1771-2656 NR 13 TC 22 Z9 22 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 3 PY 1993 VL 70 IS 18 BP 2690 EP 2693 DI 10.1103/PhysRevLett.70.2690 PG 4 WC Physics, Multidisciplinary SC Physics GA KZ989 UT WOS:A1993KZ98900008 ER PT J AU EIMERL, D MILAM, D YU, J AF EIMERL, D MILAM, D YU, J TI LARGE BANDWIDTH FREQUENCY-CONVERTED ND-GLASS LASER AT 527 NM WITH DELTA-V/V=2-PERCENT SO PHYSICAL REVIEW LETTERS LA English DT Article ID ROTATIONAL RAMAN-SCATTERING; CONVERSION; ATMOSPHERE AB Large bandwidth in lasers for inertial confinement fusion is potentially capable of controlling laser-plasma instabilities. We have demonstrated the efficient generation of large bandwidth, DELTAnu/nu=2%, in a frequency-doubled Nd:glass laser at 527 nm, using stimulated rotational Raman scattering in atmospheric pressure nitrogen gas. Its use in a fusion laser would involve the use of a multilens array to produce multiple foci where the broadband conversion takes place. This technique is also effective for frequency tripled or quadrupled lasers at 351 or 263 nm. RP EIMERL, D (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 5808,LIVERMORE,CA 94551, USA. NR 23 TC 13 Z9 13 U1 4 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 3 PY 1993 VL 70 IS 18 BP 2738 EP 2741 DI 10.1103/PhysRevLett.70.2738 PG 4 WC Physics, Multidisciplinary SC Physics GA KZ989 UT WOS:A1993KZ98900020 ER PT J AU POTTLACHER, G HIXSON, RS MELNITZKY, S KASCHNITZ, E WINKLER, MA JAGER, H AF POTTLACHER, G HIXSON, RS MELNITZKY, S KASCHNITZ, E WINKLER, MA JAGER, H TI THERMOPHYSICAL PROPERTIES OF POCO AXF-5Q GRAPHITE UP TO MELTING SO THERMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 11TH SYMP ON THERMOPHYSICAL PROPERTIES CY JUN 23-27, 1991 CL BOULDER, CO SP AMER SOC MECH ENGINEERS, HEAT TRANSFER DIV, NIST DE CARBON; DYNAMIC TECHNIQUES; ELECTRICAL RESISTIVITY; HEAT CAPACITY; HIGH TEMPERATURES; MELTING; POCO GRAPHITE ID PULSE-HEATING TECHNIQUE; TRIPLE POINT; LASER AB Measurements of the thermophysical properties of a particular POCO graphite (AXF-5Q) have been made up to melting. Results were obtained in two different laboratories using two heating rates. Data for temperature, volume, enthalpy, and electrical resistivity are shown. The measured melting point was found to be 4900 K +/- 200 K. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP POTTLACHER, G (reprint author), GRAZ TECH UNIV,INST EXPTL PHYS,PETERSGASSE 16,A-8010 GRAZ,AUSTRIA. OI Pottlacher, Gernot/0000-0001-8486-0515 NR 26 TC 16 Z9 16 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD MAY 3 PY 1993 VL 218 BP 183 EP 193 DI 10.1016/0040-6031(93)80421-6 PG 11 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA LE313 UT WOS:A1993LE31300015 ER PT J AU PITZER, KS STERNER, SM AF PITZER, KS STERNER, SM TI EQUATIONS OF STATE FOR SOLID NACL-KCL AND SATURATED LIQUID NACL-KCL-H2O SO THERMOCHIMICA ACTA LA English DT Article ID DIFFERENTIAL THERMAL-ANALYSIS; SYSTEM NACL-KCL-H2O; PHASE-RELATIONS; THERMODYNAMICS; HALITE; BARS AB The equilibrium between the solid solution of NaCl-KCl and the ternary liquid NaCl-KCl-H2O is both scientifically interesting and geologically important. Equations of the Margules type have been derived for the two phases that accurately reproduce the extensive array of published measurements, together with recent measurements of Chou for the liquidus of the ternary and the solidus of the NaCl-KCl binary. The range of validity of the equations extends to 1200 K, to 5 kbar, but for the aqueous system it is limited to compositions on the salt saturation surface. Of particular interest is the transition in the liquid-solid equilibrium of the ternary from the pattern at high temperatures where the solid is a solution of composition near that of the liquid to that at lower temperatures where the solid is nearly pure NaCl or KCl. The phase compositions for anhydrous NaCl-KCl are consistent with the heat of mixing data of Hersh and Kleppa and yield a new expression for the entropy of mixing. C1 LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. RP UNIV CALIF BERKELEY, DEPT CHEM, BERKELEY, CA 94720 USA. NR 15 TC 2 Z9 2 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 EI 1872-762X J9 THERMOCHIM ACTA JI Thermochim. Acta PD MAY 3 PY 1993 VL 218 BP 413 EP 423 DI 10.1016/0040-6031(93)80440-L PG 11 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA LE313 UT WOS:A1993LE31300034 ER PT J AU MARTZ, HE SCHNEBERK, DJ ROBERSON, GP MONTEIRO, PJM AF MARTZ, HE SCHNEBERK, DJ ROBERSON, GP MONTEIRO, PJM TI COMPUTERIZED-TOMOGRAPHY ANALYSIS OF REINFORCED-CONCRETE SO ACI MATERIALS JOURNAL LA English DT Article DE GAMMA-RAYS; NONDESTRUCTIVE TESTS; REINFORCED CONCRETE AB Gamma-ray computerized tomography (CT) has the potential of being a powerful nondestructive method to assess the degree of distress existing in reinforced concrete members. This paper presents a feasibility study of using CT to inspect reinforced concrete specimens. One of the main objectives was to verify the CT resolution in determining the size and location of voids and reinforcing bars. To assess the efficiency of CT in determining large voids, a concrete cylinder was cast with a conical hole centered along its longitudinal axis. The hole was posteriorly filled with a material of similar density but higher atomic number, and the specimen was reanalyzed to determine CT's capacity in distinguishing changes in material composition. To evaluate the efficiency of CT in establishing the location of reinforcing bars, a concrete cylinder with a reinforcing bar embedded in its center and a cube with reinforcing bars distributed along its diagonal were used. The results indicate that CT was able to resolve the many different phases in reinforced concrete (reinforced bars, concrete, and voids) with great accuracy. C1 UNIV CALIF BERKELEY,BERKELEY,CA 94720. RP MARTZ, HE (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 14 TC 19 Z9 22 U1 0 U2 1 PU AMER CONCRETE INST PI FARMINGTON HILLS PA 38800 INTERNATIONAL WAY, COUNTRY CLUB DRIVE, PO BOX 9094, FARMINGTON HILLS, MI 48333-9094 SN 0889-325X J9 ACI MATER J JI ACI Mater. J. PD MAY-JUN PY 1993 VL 90 IS 3 BP 259 EP 264 PG 6 WC Construction & Building Technology; Materials Science, Multidisciplinary SC Construction & Building Technology; Materials Science GA LU105 UT WOS:A1993LU10500009 ER PT J AU HUGHES, DA AF HUGHES, DA TI MICROSTRUCTURAL EVOLUTION IN A NON-CELL FORMING METAL - AL-MG SO ACTA METALLURGICA ET MATERIALIA LA English DT Article ID ENERGY DISLOCATION-STRUCTURES; SHEAR BAND FORMATION; SINGLE-CRYSTALS; DEFORMATION; PLANE; SLIP AB Microstructural evolution in Al + 5.5 at.% Mg lightly deformed by rolling was studied using transmission electron microscopy. Observations show that the dislocations are organized into a Taylor lattice containing multiple burgers vectors and having alternating misorientations along {111} slip planes. These observations are in contrast to the usual description of these structures as ''random'' dislocation tangles. With increasing strain, a grain is subdivided into several domains of differently oriented Taylor lattices. The newly observed boundaries between different domains are long single dislocations walls formed along {111}. As a further evolutionary progression, the single walled domain boundaries develop into microbands. The observed grain subdivision parallels that observed in cell forming metals. Subdivision occurs to accommodate strain using fewer slip systems than required by the Taylor criterion. RP HUGHES, DA (reprint author), SANDIA NATL LABS, DEPT MAT, LIVERMORE, CA 94550 USA. NR 34 TC 162 Z9 166 U1 4 U2 19 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0956-7151 J9 ACTA METALL MATER JI Acta Metall. Mater. PD MAY PY 1993 VL 41 IS 5 BP 1421 EP 1430 DI 10.1016/0956-7151(93)90251-M PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA LA003 UT WOS:A1993LA00300010 ER PT J AU BOUZAHER, A BONNET, R AF BOUZAHER, A BONNET, R TI MISFIT DISLOCATIONS ARRANGED IN A HEXAGONAL NETWORK IN ANISOTROPIC ELASTICITY - RELATED DISPLACEMENT FIELD AND STORED ELASTIC ENERGY SO ACTA METALLURGICA ET MATERIALIA LA English DT Article ID ELECTRON-MICROSCOPY; GRAIN-BOUNDARIES; INTERFACIAL BOUNDARIES; LATTICE MISFIT; METALS; ALLOY AB A method presented in a previous paper to determine any biperiodic elastic displacement field (Bonnet, 1981) is developed analytically for a hexagonal network of misfit dislocations lying along a plane separating two different anisotropic crystals. The network is possibly non-regular. The three components of the displacement field are expressed, in both the crystals, as double Fourier series. Each harmonic term depends on coefficients calculated from the roots of a sextic polynomial whose coefficients generalize those established by Eshelby et al. (1953). For the particular case of a regular hexagonal network, analytical expressions are obtained for the stored elastic energy E(S) when (i) the Burgers vectors are parallel to the interface and (ii) each crystal has an elastic symmetry axis perpendicular to the interface. Applications to low angle twist boundaries parallel to (111) planes in fc.c. materials (Al, Cu) and the heterotwin (111)Si parallel-to (111)CoSi2 interface show in fact small effects of the anisotropy of these crystals on the values of E(S). C1 LAWRENCE BERKELEY LAB, NATL CTR ELECTRON MICROSCOPY, BERKELEY, CA 94720 USA. RP BOUZAHER, A (reprint author), DOMAINE UNIV, INST NATL POLYTECH GRENOBLE, ENSEEG LTPCM, URA 29, BP 75, F-38402 ST MARTIN DHERES, FRANCE. NR 29 TC 7 Z9 7 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0956-7151 J9 ACTA METALL MATER JI Acta Metall. Mater. PD MAY PY 1993 VL 41 IS 5 BP 1595 EP 1603 DI 10.1016/0956-7151(93)90268-W PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA LA003 UT WOS:A1993LA00300027 ER PT J AU TURNER, PC AF TURNER, PC TI LOW-COST (QUESTIONABLE) TITANIUM-ALLOYS - REPLY SO ADVANCED MATERIALS & PROCESSES LA English DT Letter RP TURNER, PC (reprint author), US BUR MINES,ALBANY RES CTR,ALBANY,OR, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 SN 0026-0665 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD MAY PY 1993 VL 143 IS 5 BP 80 EP 80 PG 1 WC Materials Science, Multidisciplinary SC Materials Science GA LC872 UT WOS:A1993LC87200009 ER PT J AU CEMAN, DL RADER, DJ OHERN, TJ AF CEMAN, DL RADER, DJ OHERN, TJ TI CALIBRATION OF THE PHASE DOPPLER PARTICLE ANALYZER WITH MONODISPERSE DROPLETS SO AEROSOL SCIENCE AND TECHNOLOGY LA English DT Article ID SIZE; VELOCITY AB The experimental response of the phase Doppler particle analyzer (Aerometrics, Inc., Sunnyvale, CA) to monodisperse oleic acid droplets in the 2.3-24-mum range is presented for three optical configurations. Significant nonlinearities for droplets with diameters < 20 mum were seen when using the standard configuration of a 495-mm focal length receiving lens at an off-forward scattering angle of theta = 30-degrees. Of particular concern are response oscillations < 7 mum that lead to multivalued regions. In order to reduce these nonlinearities, two improvements to the standard receiver configuration were studied as suggested by theoretical studies reported in the literature. First, the receiver focal length was shortened to 240 mm (at theta = 30-degrees) to increase the integration of scattered light. As expected, the instrument response did significantly improve over the standard case, both in terms of linearity and scatter, for droplets > 5 mum. A significant departure from linearity (undersizing by 1.7 mum for a 2.3-mum indicated droplet diameter) was observed below this size, although the multivalued region of response was greatly reduced. Second, the receiving lens (focal length of 240 mm) was configured at a collection angle of 70-degrees, close to the Brewster angle for oleic acid droplets where interference from reflected light should be minimized. Surprisingly, the performance of this configuration was comparable to the standard case (even though a shorter focal length was used), and inferior to the 240-mm/30-degrees configuration. C1 SANDIA NATL LABS,DEPT FLUID & THERMAL SCI,ALBUQUERQUE,NM 87185. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. NR 18 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0278-6826 J9 AEROSOL SCI TECH JI Aerosol Sci. Technol. PD MAY PY 1993 VL 18 IS 4 BP 346 EP 358 DI 10.1080/02786829308959609 PG 13 WC Engineering, Chemical; Engineering, Mechanical; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA KY254 UT WOS:A1993KY25400003 ER PT J AU MARTIN, HW GRAETZ, DA LOCASCIO, SJ HENSEL, DR AF MARTIN, HW GRAETZ, DA LOCASCIO, SJ HENSEL, DR TI NITRIFICATION INHIBITOR INFLUENCES ON POTATO SO AGRONOMY JOURNAL LA English DT Article ID NITROGEN; DICYANDIAMIDE; YIELD; SOILS; UREA AB Nitrification inhibitors may reduce loss of fertilizer N from the root zone by reducing leaching and denitrification. This reduced N loss should be reflected in increased crop yields. These studies were conducted to determine if potato yield, specific gravity, or leaf N at flowering would be increased by use of nitrification inhibitors. Nitrification inhibitors dicyandiamide (DCD) and 2-chloro-6-(trichloromethyl)-pyridine (nitrapyrin) were evaluated in five studies on potato (Solanum tuberosum L. cv. Atlantic) in Northeast Florida on an Arenic Ochraqualf, a Grossarenic Paleudult, and a Grossarenic Paleaquult. Treatments were combinations of N at 67, 134, and 202 kg ha-1; DCD at 0, 5.6, and 11.2 kg ha-1; nitrapyrin at 0.56 and 1.12 kg ha-1; and isobutylidene diurea (IBDU) applied as one-third of the N. Tuber yields were not affected by nitrification inhibitors in four of five tests but were increased 14% in one test. Nitrification inhibitors increased leaf N concentration at flowering in three of four tests. Tuber yields were higher with DCD than with nitrapyrin in three of rive tests. In several year-location combinations, use of IBDU resulted in greater tuber yield and leaf N concentration at flowering than did nitrification inhibitors. Based on these results, nitrification inhibitors can not be recommended for potato production on hyperthermic, sandy, irrigated soils. C1 UNIV FLORIDA,DEPT SOIL SCI,GAINESVILLE,FL 32611. UNIV FLORIDA,DEPT VEGETABLE CROPS,GAINESVILLE,FL 32611. RP MARTIN, HW (reprint author), UNIV GEORGIA,DIV ECOL,SAVANNAH RIVER ECOL LAB,DRAWER E,AIKEN,SC 29802, USA. NR 27 TC 12 Z9 14 U1 0 U2 7 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 SN 0002-1962 J9 AGRON J JI Agron. J. PD MAY-JUN PY 1993 VL 85 IS 3 BP 651 EP 655 PG 5 WC Agronomy SC Agriculture GA LH463 UT WOS:A1993LH46300024 ER PT J AU WITKOWSKI, WR ALLEN, JJ AF WITKOWSKI, WR ALLEN, JJ TI APPROXIMATION OF PARAMETER UNCERTAINTY IN NONLINEAR OPTIMIZATION-BASED PARAMETER-ESTIMATION SCHEMES SO AIAA JOURNAL LA English DT Article AB Theoretical models are often developed using experimental data to estimate the model parameters, but an evaluation is not always made of the model's reliability or robustness. Errors can exist in the theoretical model for many reasons, including inadequate model formulation and poor parameter estimates. This paper investigates the approximation of second-order statistics (confidence regions) of Parameters estimated using nonlinear optimization schemes. An optimal set of parameters is calculated to minimize the difference between theoretical model predictions and experimental data. This metric is formulated in terms of a weighted least squares objective function. A truss structure was analyzed to evaluate nonlinear optimization and confidence region approximation techniques. It was found that since the truss model was linear and parameter interaction was small, the confidence region approximations were reliable. RP WITKOWSKI, WR (reprint author), SANDIA NATL LABS,DEPT STRUCT DYNAM 1434,ALBUQUERQUE,NM 87185, USA. NR 14 TC 8 Z9 8 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD MAY PY 1993 VL 31 IS 5 BP 947 EP 950 DI 10.2514/3.11709 PG 4 WC Engineering, Aerospace SC Engineering GA LC444 UT WOS:A1993LC44400025 ER PT J AU SEIDELMORGENSTERN, A GUIOCHON, G AF SEIDELMORGENSTERN, A GUIOCHON, G TI THEORETICAL-STUDY OF RECYCLING IN PREPARATIVE CHROMATOGRAPHY SO AICHE JOURNAL LA English DT Article ID LIQUID-CHROMATOGRAPHY; HIGH RESOLUTION; HIGH-SPEED; SEPARATION; ENANTIOMERS; SIMULATION AB Using the equilibrium-dispersive model of chromatography, we have investigated recycling as a means to improve the recovery yields and possibly the production rates of chromatographic separations. When compared with the optimal values obtained for the conventional single-cycle regime, our results prove the potential for recycling in preparative chromatography. The analysis performed for the separation of two binary mixtures demonstrates that recycling not only improves the recovery yield but can increase the production rate under certain conditions. Different possibilities of collecting sufficiently separated fractions during recycling are compared. The mathematical model developed can be used effectively for designing optimal recycling strategies in preparative liquid chromatography. C1 UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37831. OI Seidel-Morgenstern, Andreas/0000-0001-8595-7810 NR 29 TC 43 Z9 43 U1 0 U2 4 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 MAY PY 1993 VL 39 IS 5 BP 809 EP 819 DI 10.1002/aic.690390509 PG 11 WC Engineering, Chemical SC Engineering GA LB875 UT WOS:A1993LB87500008 ER PT J AU HINO, T LAMBERT, SM SOANE, DS PRAUSNITZ, JM AF HINO, T LAMBERT, SM SOANE, DS PRAUSNITZ, JM TI LATTICE THERMODYNAMICS FOR BINARY CLOSED-LOOP EQUILIBRIA - ORDINARY AND POLYMER SYSTEMS SO AICHE JOURNAL LA English DT Article ID CRITICAL SOLUTION TEMPERATURES; STATISTICAL THERMODYNAMICS; PHASE-DIAGRAMS; FIELD-THEORY; MIXTURES; MODEL; BEHAVIOR; CURVES AB The incompressible lattice-gas model by ten Brinke and Karasz is adopted to introduce the effect of specific interactions into a recently-presented Monte-Carlo-based lattice expression for the Helmholtz energy of nonrandom mixing. While the lattice remains incompressible, intermolecular forces consist of two types: London dispersion forces and specific (chemical) forces. The specific interactions between similar components, as well as those between dissimilar components, are incorporated in a systematic manner. Closed-loop temperature-composition phase diagrams are obtained. The theory is compared with experimental data for several binary systems, including polymer solutions, which exhibit closed-loop coexistence curves. Theoretical and experimental results are in good agreement. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV MAT & CHEM SCI,BERKELEY,CA 94720. NR 35 TC 16 Z9 16 U1 0 U2 1 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 MAY PY 1993 VL 39 IS 5 BP 837 EP 845 DI 10.1002/aic.690390512 PG 9 WC Engineering, Chemical SC Engineering GA LB875 UT WOS:A1993LB87500011 ER PT J AU JANTZEN, CM BROWN, KG AF JANTZEN, CM BROWN, KG TI STATISTICAL PROCESS-CONTROL OF GLASS MANUFACTURED FOR NUCLEAR WASTE-DISPOSAL SO AMERICAN CERAMIC SOCIETY BULLETIN LA English DT Article AB Process and product quality models based on glass composition have been developed which simplify the fabrication of the glass while ensuring glass processibility and quality. These models help to form the foundation of the statistical process control system used to monitor and control glass composition. RP JANTZEN, CM (reprint author), WESTINGHOUSE SAVANNAH RIVER CO,SAVANNAH RIVER TECHNOL CTR,AIKEN,SC 29808, USA. NR 10 TC 8 Z9 8 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7812 J9 AM CERAM SOC BULL JI Am. Ceram. Soc. Bull. PD MAY PY 1993 VL 72 IS 5 BP 55 EP 59 PG 5 WC Materials Science, Ceramics SC Materials Science GA LX017 UT WOS:A1993LX01700005 ER PT J AU RICHMOND, MD YEUNG, ES AF RICHMOND, MD YEUNG, ES TI DEVELOPMENT OF LASER-EXCITED INDIRECT FLUORESCENCE DETECTION FOR HIGH-MOLECULAR-WEIGHT POLYSACCHARIDES IN CAPILLARY ELECTROPHORESIS SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID ANION-EXCHANGE CHROMATOGRAPHY; ZONE ELECTROPHORESIS; MASS-SPECTROMETRY; GEL-ELECTROPHORESIS; OLIGOSACCHARIDES; GLYCOPROTEINS; SEPARATIONS; SENSITIVITY C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 26 TC 29 Z9 31 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 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD MAY 1 PY 1993 VL 210 IS 2 BP 245 EP 248 DI 10.1006/abio.1993.1190 PG 4 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA KZ609 UT WOS:A1993KZ60900005 PM 7685564 ER PT J AU AHMED, FE AF AHMED, FE TI UREA FACILITATES QUANTITATIVE ESTIMATION OF DNA DAMAGE INSITU BY PREVENTING ITS DEGRADATION SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID INDUCED SINGLE-STRAND; GEL-ELECTROPHORESIS; PYRIMIDINE DIMERS; MOLECULAR-WEIGHT; MAMMALIAN-CELLS; REPAIR; BREAKS RP AHMED, FE (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. NR 19 TC 2 Z9 2 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 MAY 1 PY 1993 VL 210 IS 2 BP 253 EP 257 DI 10.1006/abio.1993.1192 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA KZ609 UT WOS:A1993KZ60900007 PM 8390138 ER PT J AU RIBEIRO, EA SUTHERLAND, JC AF RIBEIRO, EA SUTHERLAND, JC TI RESOLVING POWER - A QUANTITATIVE MEASURE OF ELECTROPHORETIC RESOLUTION SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID GEL-ELECTROPHORESIS; FLUORESCENCE DETECTION; AGAROSE GELS; DNA LENGTH; SEQUENCE; FRAGMENTS; MOBILITY; ACID C1 BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973. FU NHGRI NIH HHS [HG00371] NR 36 TC 8 Z9 8 U1 0 U2 4 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 MAY 1 PY 1993 VL 210 IS 2 BP 378 EP 388 DI 10.1006/abio.1993.1211 PG 11 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA KZ609 UT WOS:A1993KZ60900026 PM 8512074 ER PT J AU RICIPUTI, LR CHRISTIE, WH COLE, DR ROSSEEL, TM AF RICIPUTI, LR CHRISTIE, WH COLE, DR ROSSEEL, TM TI ANALYSIS OF RARE-EARTH ELEMENTS IN SILICATES BY ION MICROPROBE USING DOUBLY-CHARGED IONS SO ANALYTICAL CHEMISTRY LA English DT Article ID ACCESSORY MINERALS; MASS-SPECTROMETRY AB A technique for measurement of rare earth element (REE) concentrations in silicates using a Cameca ims-4f ion microprobe and doubly-charged, odd-mass isotopes has been developed. The secondary ion spectra of the doubly-charged odd-mass REE are virtually free of interferences, allowing measurements to be carried out at low energies and without the need for spectral stripping. Calibration lines have been established for La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er, Tm, and Yb using a suite of clinopyroxene standards. This technique offers a relatively fast, simple approach for the in-situ analysis of REE on spots of <20 mum and detection limits of <15 ppb for most elements. C1 OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT GEOL SCI,KNOXVILLE,TN 37996. RP RICIPUTI, LR (reprint author), OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37831, USA. RI Rosseel, Thomas/J-4086-2016 OI Rosseel, Thomas/0000-0001-9917-7073 NR 17 TC 12 Z9 12 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAY 1 PY 1993 VL 65 IS 9 BP 1186 EP 1191 DI 10.1021/ac00057a014 PG 6 WC Chemistry, Analytical SC Chemistry GA KZ659 UT WOS:A1993KZ65900015 ER PT J AU TELLINGHUISEN, J WILKERSON, CW AF TELLINGHUISEN, J WILKERSON, CW TI BIAS AND PRECISION IN THE ESTIMATION OF EXPONENTIAL DECAY PARAMETERS FROM SPARSE DATA SO ANALYTICAL CHEMISTRY LA English DT Article AB The statistical properties of maximum likelihood (ML) and least-squares (LS) estimators for the exponential decay parameters GAMMA(rate) and tau (lifetime) are examined for finite observation time (T) and a small number of counts (N). The ML estimators and their variances are assessed via numerical calculations employing the exact N-point distributions for exponentially distributed random data. Bias is a common feature of all these estimators under these conditions. In addition, the ML lifetime estimator exhibits the interesting property of divergence in its variance, which means that GAMMA is the statistically preferred parameter for characterizing exponential decay for finite observation time. The bias in GAMMA is less than N/(N - 1) for all T and thus can be easily corrected for. The effects of various ways of binning the data are examined for both the ML and LS approaches. C1 LOS ALAMOS NATL LAB,CTR HUMAN GENOME STUDIES,DIV CHEM & LASER SCI,LOS ALAMOS,NM 87545. RP TELLINGHUISEN, J (reprint author), VANDERBILT UNIV,DEPT CHEM,NASHVILLE,TN 37235, USA. NR 17 TC 49 Z9 49 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 MAY 1 PY 1993 VL 65 IS 9 BP 1240 EP 1246 DI 10.1021/ac00057a022 PG 7 WC Chemistry, Analytical SC Chemistry GA KZ659 UT WOS:A1993KZ65900023 ER PT J AU BELANI, K SESSLER, DI SESSLER, AM SCHROEDER, M MCGUIRE, J MERRIFIELD, B WASHINGTON, DE MOAYERI, A AF BELANI, K SESSLER, DI SESSLER, AM SCHROEDER, M MCGUIRE, J MERRIFIELD, B WASHINGTON, DE MOAYERI, A TI LEG HEAT-CONTENT CONTINUES TO DECREASE DURING THE CORE TEMPERATURE PLATEAU IN HUMANS ANESTHETIZED WITH ISOFLURANE SO ANESTHESIOLOGY LA English DT Article DE ANESTHESIA, VOLATILE, ISOFLURANE; BRAIN, HYPOTHALAMUS; HEAT; HYPOTHERMIA; MEASUREMENT TECHNIQUES, BLOOD FLOW, LASER DOPPLER; SKIN-TEMPERATURE GRADIENT; VASOMOTOR INDEX; VOLUME PLETHYSMOGRAPHY; TEMPERATURE, MEASUREMENT, SKIN; ESOPHAGEAL; TEMPERATURE, REGULATION, SETPOINT; THRESHOLD; VASOCONSTRICTION; THERMOREGULATION; VASOCONSTRICTION, VASODILATION, THERMOREGULATORY ID FINGERTIP BLOOD-FLOW; THERMOREGULATORY THRESHOLD; BODY-COMPOSITION; ANESTHESIA; HYPOTHERMIA; FENTANYL; AGE AB Background. Sufficient hypothermia during anesthesia provokes thermoregulatory responses, but the clinical significance of these responses remains unknown. Nonshivering thermogenesis does not increase metabolic heat production in anesthetized adults. Vasoconstriction reduces cutaneous heat loss, but the initial decrease appears insufficient to cause a thermal steady state (heat production equaling heat loss). Accordingly, the authors tested the hypotheses that: 1) thermoregulatory vasoconstriction prevents further core hypothermia; and 2) the resulting stable core temperature is not a thermal steady state, but, instead, is accompanied for several hours by a continued reduction in body heat content. Methods. Six healthy volunteers were anesthetized with isoflurane (0.8%) and paralyzed with vecuronium. Core hypothermia was induced by fan cooling, and continued for 3 h after vasoconstriction in the legs was detected. Leg heat content was calculated from six needle thermocouples and skin temperature, by integrating the resulting parabolic regression over volume. Results. Core temperature decreased 1.0 +/- 0.2-degrees-C in the 1 h before vasoconstriction, but only 0.4 +/- 0.3-degrees-C in the subsequent 3 h. This temperature decrease, evenly distributed throughout the body, would reduce leg heat content 10 kcal. However, measured leg heat content decreased 49 +/- 18 kcal in the 3 h after vasoconstriction. Conclusions. These data thus indicate that thermoregulatory vasoconstriction produces a clinically important reduction in the rate of core cooling. This core temperature plateau resulted, at least in part, from sequestration of metabolic heat to the core which allowed core temperature to remain nearly constant, despite a continually decreasing body heat content. C1 UNIV CALIF SAN FRANCISCO,DEPT ANESTHESIA,ROOM C-214,SAN FRANCISCO,CA 94143. UNIV MINNESOTA,MINNEAPOLIS,MN 55455. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. FU NIGMS NIH HHS [GM39723] NR 39 TC 84 Z9 85 U1 0 U2 0 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0003-3022 J9 ANESTHESIOLOGY JI Anesthesiology PD MAY PY 1993 VL 78 IS 5 BP 856 EP 863 DI 10.1097/00000542-199305000-00008 PG 8 WC Anesthesiology SC Anesthesiology GA LA777 UT WOS:A1993LA77700007 PM 8489057 ER PT J AU NALESSO, GF JACOBSON, AR AF NALESSO, GF JACOBSON, AR TI ON A MECHANISM FOR DUCTING OF ACOUSTIC AND SHORT-PERIOD ACOUSTIC-GRAVITY WAVES BY THE UPPER ATMOSPHERIC THERMOCLINE SO ANNALES GEOPHYSICAE-ATMOSPHERES HYDROSPHERES AND SPACE SCIENCES LA English DT Article AB In this paper, we prove analytically that the upper atmospheric thermocline can support ducted acoustic and acoustic-gravity waves without the necessity of including a ground rigid surface, or a sound-speed minimum at the mesopause, or dissipative mechanisms. By considering a suitable monotonically increasing temperature profile, close to the average atmospheric profile, we obtain the dispersion relation for the guided modes together with the associated eigensolutions. C1 LOS ALAMOS NATL LAB,DIV SPACE SCI & TECHNOL,ATMOSPHER SCI GRP,LOS ALAMOS,NM 87535. RP NALESSO, GF (reprint author), UNIV PADUA,DIPARTIMENTO ELETTR & INFORMAT,VIA GRADENIGO 6-A,I-35131 PADUA,ITALY. NR 12 TC 10 Z9 10 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0992-7689 J9 ANN GEOPHYS JI Ann. Geophys.-Atmos. Hydrospheres Space Sci. PD MAY PY 1993 VL 11 IS 5 BP 372 EP 376 PG 5 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA LG843 UT WOS:A1993LG84300004 ER PT J AU AYOUBI, IS AF AYOUBI, IS TI THE RIEMANN-GREEN FUNCTION AND THE INVARIANT IMBEDDING EQUATIONS FOR HYPERBOLIC SYSTEMS OF 1ST-ORDER SO APPLIED MATHEMATICS AND COMPUTATION LA English DT Article ID DISSIPATIVE WAVE-EQUATION; INVERSE SCATTERING; TIME DOMAIN; OPERATORS AB In the present paper We deal with a boundary value problem for a hyperbolic system of first-order in one space variable. An explicit integral representation for the Riemann-Green function is first obtained, from which a set of discontinuities at both the initial time and along certain characteristics are calculated next. The reflection and transmission functions are then defined by simply evaluating this function at certain boundary points, and finally, a set of integro/partial differential equations satisfied by the reflection and transmission functions is derived. These are the time-dependent invariant imbedding equations for the systems we consider here, and these extend the results obtained by Corones and Knieger for second-order hyperbolic equations. C1 AMES LAB,DIV APPL MATH SCI,AMES,IA. RP AYOUBI, IS (reprint author), KING FAHD UNIV PETR & MINERALS,DEPT MATH SCI,DHAHRAN 31261,SAUDI ARABIA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0096-3003 J9 APPL MATH COMPUT JI Appl. Math. Comput. PD MAY PY 1993 VL 55 IS 2-3 BP 101 EP 129 DI 10.1016/0096-3003(93)90017-9 PG 29 WC Mathematics, Applied SC Mathematics GA KY456 UT WOS:A1993KY45600001 ER PT J AU WENDROFF, B WARNOCK, T STILLER, L MAYER, D BRICKNER, R AF WENDROFF, B WARNOCK, T STILLER, L MAYER, D BRICKNER, R TI BITS AND PIECES - CONSTRUCTING CHESS ENDGAME DATABASES ON PARALLEL AND VECTOR ARCHITECTURES SO APPLIED NUMERICAL MATHEMATICS LA English DT Article AB An endgame database for chess encodes optimal lines of play for a specific endgame involving a small number of pieces. The computation of such a database is feasible for as many as six pieces provided the inherent parallelism in the problem is fully exploited. Two computer architectures which can do this are the SIMD CM-2 and the vector multiprocessor YMP. For each machine the computer programs operate on sets of chess positions, each position represented by a single bit. The high-level algorithm is an iterative backtracking procedure. After describing endgame databases and classifying the complexity of endgames we outline the algorithms and give some details of their implementation in Fortran for parallel and vector architectures. For endgames with five or more pieces it is important to use the symmetries of the chess board to reduce storage requirements, and we indicate briefly how this can be done for the vector architecture. Some timing comparisons are presented. C1 LOS ALAMOS NATL LAB,DIV C,LOS ALAMOS,NM 87454. LOS ALAMOS NATL LAB,ADV COMP LAB,LOS ALAMOS,NM 87454. JOHNS HOPKINS UNIV,DEPT COMP SCI,BALTIMORE,MD 21218. UNIV CALIF SAN DIEGO,SAN DIEGO,CA 92103. LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87454. RP WENDROFF, B (reprint author), LOS ALAMOS NATL LAB,DIV T,LOS ALAMOS,NM 87454, USA. NR 9 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9274 J9 APPL NUMER MATH JI Appl. Numer. Math. PD MAY PY 1993 VL 12 IS 1-3 BP 285 EP 295 DI 10.1016/0168-9274(93)90123-9 PG 11 WC Mathematics, Applied SC Mathematics GA LH788 UT WOS:A1993LH78800016 ER PT J AU KOWALSKI, MP SEELY, JF HUNTER, WR RIFE, JC BARBEE, TW HOLLAND, GE BOYER, CN BROWN, CM CRUDDACE, RG AF KOWALSKI, MP SEELY, JF HUNTER, WR RIFE, JC BARBEE, TW HOLLAND, GE BOYER, CN BROWN, CM CRUDDACE, RG TI DUAL-WAVEBAND OPERATION OF A MULTILAYER-COATED DIFFRACTION GRATING IN THE SOFT-X-RAY RANGE AT NEAR-NORMAL INCIDENCE SO APPLIED OPTICS LA English DT Article DE DIFFRACTION GRATING; MULTILAYER COATING; EXTREME ULTRAVIOLET ID EXTREME ULTRAVIOLET; PERFORMANCE AB A concave diffraction grating (2400 grooves/mm) coated with a Si/Mo multilayer has an efficiency of 2.5% at 290 angstrom and a resolving power of 14,000 in third order of 156 angstrom. C1 SFA INC, LANDOVER, MD 20785 USA. USRA, WASHINGTON, DC 20024 USA. LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RP KOWALSKI, MP (reprint author), USN, RES LAB, WASHINGTON, DC 20375 USA. NR 11 TC 26 Z9 26 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD MAY 1 PY 1993 VL 32 IS 13 BP 2422 EP 2425 PG 4 WC Optics SC Optics GA KZ608 UT WOS:A1993KZ60800032 PM 20820400 ER PT J AU GUYOTSIONNEST, NS MARONI, VA AF GUYOTSIONNEST, NS MARONI, VA TI USE OF HALOCARBON OILS AS A MATRIX FOR TRANSMISSION SPECTROSCOPIC STUDIES OF SOLID INORGANIC MATERIALS IN THE NEAR-INFRARED AND VISIBLE REGIONS SO APPLIED SPECTROSCOPY LA English DT Article DE HALOCARBON OIL; TRANSMISSION SPECTROSCOPY; NEAR-INFRARED; VISIBLE AB Halocarbon oils are shown to be a useful matrix for transmission spectroscopic studies of solid inorganic materials in the near-infrared and visible regions. Absorption spectra of these oils are flat and featureless between 5000 and 32,000 cm-1. The halocarbon oils are inert to virtually all types of inorganic substances at room temperature. Light scattering appeared to be reduced for the more viscous of two halocarbon oils investigated. Examples of the application of the halocarbon oil mull technique are given for three inorganic substances: chromium(III) potassium sulfate dodecahydrate, nickel(II) hydroxide, and silicotungstic acid. C1 ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439. NR 15 TC 0 Z9 0 U1 0 U2 3 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA PO BOX 1438, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD MAY PY 1993 VL 47 IS 5 BP 556 EP 559 DI 10.1366/0003702934067252 PG 4 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA LE575 UT WOS:A1993LE57500006 ER PT J AU SHUM, SCK JOHNSON, SK PANG, HM HOUK, RS AF SHUM, SCK JOHNSON, SK PANG, HM HOUK, RS TI SPATIALLY RESOLVED MEASUREMENTS OF SIZE AND VELOCITY DISTRIBUTIONS OF AEROSOL DROPLETS FROM A DIRECT INJECTION NEBULIZER SO APPLIED SPECTROSCOPY LA English DT Article DE PNEUMATIC NEBULIZATION; DIRECT INJECTION NEBULIZATION; DROPLET SIZE MEASUREMENTS; PHASE DOPPLER PARTICLE ANALYSIS ID INDUCTIVELY COUPLED PLASMA; MASS-SPECTROMETRY; PHASE DOPPLER; DUAL-BEAM; INTERFEROMETRY; SPRAYS AB Aerosol droplet sizes and velocities from a direct injection nebulizer (DIN) are measured with radial and axial spatial resolution by phase Doppler particle analysis (PDPA). The droplets on the central axis of the spray become finer and their size becomes more uniform when almost-equal-to 20% methanol is added to the usual aqueous solvent. This could explain why the analyte signal is a maximum at this solvent composition when the DIN is used for inductively coupled plasma-mass spectrometry (ICP-MS). Mean droplet velocities are 12 to 22 m s-1 with standard deviations of +/-4 to +/-7 m s-1. The outer fringes of the aerosol plume tend to be enriched in large droplets. The Sauter mean diameter (D3.2) and velocity of the droplets also vary substantially with axial position in the aerosol plume. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,DEPT CHEM,AMES,IA 50011. NR 37 TC 36 Z9 36 U1 1 U2 5 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA PO BOX 1438, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD MAY PY 1993 VL 47 IS 5 BP 575 EP 585 DI 10.1366/0003702934067108 PG 11 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA LE575 UT WOS:A1993LE57500009 ER PT J AU NIVENS, DE SCHMIT, J SNIATECKI, J ANDERSON, T CHAMBERS, JQ WHITE, DC AF NIVENS, DE SCHMIT, J SNIATECKI, J ANDERSON, T CHAMBERS, JQ WHITE, DC TI MULTICHANNEL ATR/FT-IR SPECTROMETER FOR ONLINE EXAMINATION OF MICROBIAL BIOFILMS SO APPLIED SPECTROSCOPY LA English DT Note DE FT-IR; BIOFILMS; INFRARED SPECTROSCOPY; ATR SPECTROSCOPY; CAULOBACTER; PHA C1 UNIV TENNESSEE,CTR ENVIRONM BIOTECHNOL,KNOXVILLE,TN 37932. OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. RP NIVENS, DE (reprint author), UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37932, USA. NR 13 TC 25 Z9 25 U1 1 U2 4 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA PO BOX 1438, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD MAY PY 1993 VL 47 IS 5 BP 668 EP 671 DI 10.1366/0003702934067171 PG 4 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA LE575 UT WOS:A1993LE57500024 ER PT J AU PERRY, WL CHI, KM KODAS, T HAMPDENSMITH, M RYE, R AF PERRY, WL CHI, KM KODAS, T HAMPDENSMITH, M RYE, R TI DIRECT DEPOSITION OF PATTERNED COPPER-FILMS ON TEFLON SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT SYMP B ON LASER, LAMP AND SYNCHROTRON ASSISTED MATERIALS SURFACE PROCESSING, AT THE 1992 E-MRS SPRING CONF CY JUN 02-05, 1992 CL STRASBOURG, FRANCE SP EUROPEAN MAT RES SOC, COUNCIL EUROPE, COMMISS EUROPEAN COMMUNITIES, BANQUE POPULAIRE, BRASSERIE KRONENBOURG, CTR RECH NUCL, CNRS, ELSEVIER SCI PUBL, VILLE STRASBOURG, OFF TOURISME, EUROPEAN PARLIAMENT ID POLY(TETRAFLUOROETHYLENE); RADIATION; COMPLEXES; ADHESION AB Current subtractive methods yielding patterned Cu features on PTFE substrates rely on wet Cu etching processes. We have developed three variations of a new dry, additive patterning process. The mechanisms for patterning include Mg Kalpha X-ray-induced cross-linking, e-beam-induced cross-linking, or laser patterning. The X-ray and e-beam patterning processes rely on irradiation followed by selective etching of the non-irradiated areas. The laser patterning begins by chemically etching PTFE which leaves a rough surface with good adhesion characteristics. An argon-ion laser beam is then used to selectively remove the etched layer, revealing the underlying surface which has physical properties closely resembling unmodified Teflon. Typical laser patterning conditions are scan rates of 0.005-5.5 mm/s, incident powers of 40-380 mW at 514 nm, and base pressures of 10(-2) Torr and at atmospheric pressure in air. In all cases, CVD from (beta-diketonate)CuL compounds is used to deposit copper only on the etched regions of the sample, leaving the irradiated regions copper-free. The advantages of this procedure are: (1) subtractive Cu wet etching of copper is avoided, so no masking techniques are necessary and no liquid waste is generated; (2) ten-micron-sized features can be produced; (3) excellent adhesion is obtained. C1 CHEM ENGN DEPT,ALBUQUERQUE,NM 87131. CHEM DEPT,ALBUQUERQUE,NM 87131. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. NR 20 TC 11 Z9 12 U1 0 U2 0 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 MAY PY 1993 VL 69 IS 1-4 BP 94 EP 100 DI 10.1016/0169-4332(93)90488-W PG 7 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA LA076 UT WOS:A1993LA07600018 ER PT J AU KRAMER, KJ TALWAR, S ISHIDA, E WEINER, KH SIGMON, TW AF KRAMER, KJ TALWAR, S ISHIDA, E WEINER, KH SIGMON, TW TI FABRICATION AND CHARACTERIZATION OF SELECTIVELY GROWN SI1-XGEX/SI P+/N HETEROJUNCTIONS USING PULSED-LASER INDUCED EPITAXY AND GAS IMMERSION LASER DOPING SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT SYMP B ON LASER, LAMP AND SYNCHROTRON ASSISTED MATERIALS SURFACE PROCESSING, AT THE 1992 E-MRS SPRING CONF CY JUN 02-05, 1992 CL STRASBOURG, FRANCE SP EUROPEAN MAT RES SOC, COUNCIL EUROPE, COMMISS EUROPEAN COMMUNITIES, BANQUE POPULAIRE, BRASSERIE KRONENBOURG, CTR RECH NUCL, CNRS, ELSEVIER SCI PUBL, VILLE STRASBOURG, OFF TOURISME, EUROPEAN PARLIAMENT ID LAYERS; ALLOYS; GE; SI AB A pulsed XeCl excimer laser is used to grow ideally strained heteroepitaxial Si1-xGex/Si layers with Ge fractions up to 21% by intermixing a structure of electron beam evaporated a-Ge on Si(100). The rapid regrowth process induces an interfacial grading of the Ge fraction, which results in unusual stability of the layer strain upon heat treatment, as confirmed by MeV-ion channeling along [100] and [110]. Boron dopant is incorporated during the melt process by using a BF3 gas ambient. Hall/van der Pauw and SIMS analysis reveal that the incorporated dopant dose scales with the number of laser pulses. The junction depth is controlled by the incident laser fluence. The melt time is monitored in-situ utilizing the transient reflectance of the sample during the phase transformations. A patterned reflective aluminum mask is used to obtain spatially selective melting. In-plane Hall mobilities are found to be lower for the heteroepitaxial junctions than for Si homojunctions. We believe this is due to different transport behavior for holes in the observed doping regime of 10(18)-10(20) cm-3. Quasiplanar p+/n heterojunction diodes are fabricated and exhibit near-ideal forward I-V characteristics. Heterojunction diodes exhibit lower turn-on voltages than equivalent Si homojunction diodes, indicative of a lowered bandgap. The turn-on voltages also depend on the B junction depth with respect to the Si1-xGex/Si interface. Both quantities are controlled independently by separating the epitaxy from the doping step. C1 STANFORD UNIV,DEPT ELECT ENGN,STANFORD,CA 94305. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP KRAMER, KJ (reprint author), STANFORD UNIV,STANFORD ELECTR LABS,STANFORD,CA 94305, USA. NR 18 TC 7 Z9 7 U1 0 U2 2 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 MAY PY 1993 VL 69 IS 1-4 BP 121 EP 126 DI 10.1016/0169-4332(93)90492-T PG 6 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA LA076 UT WOS:A1993LA07600022 ER PT J AU SENTIS, ML GRANIER, P CHAZAUD, F MARINE, WI GERRY, M SZE, RC AF SENTIS, ML GRANIER, P CHAZAUD, F MARINE, WI GERRY, M SZE, RC TI VUV LIGHT PRODUCTION FROM A FORMED-FERRITE PLASMA SOURCE SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT SYMP B ON LASER, LAMP AND SYNCHROTRON ASSISTED MATERIALS SURFACE PROCESSING, AT THE 1992 E-MRS SPRING CONF CY JUN 02-05, 1992 CL STRASBOURG, FRANCE SP EUROPEAN MAT RES SOC, COUNCIL EUROPE, COMMISS EUROPEAN COMMUNITIES, BANQUE POPULAIRE, BRASSERIE KRONENBOURG, CTR RECH NUCL, CNRS, ELSEVIER SCI PUBL, VILLE STRASBOURG, OFF TOURISME, EUROPEAN PARLIAMENT AB Emission spectra from a high-current line plasma produced by means of a formed-ferrite plasma source have been measured in the 1200-2900 angstrom spectral region. The formed-ferrite plasma source was driven by a 4.6 muF capacitor bank charged up to 25 kV. In order to obtain this intense flash light source, a conducting channel was first made on the ferrite surface which has a measurable high impedance, but orders of magnitudes less than the impedance of the unprocessed ferrite (> 10(5) kOMEGA . cm). Two different methods were successfully used: laser ablation and explosion of a brass wire. A study of the formation and the characteristics of the channel and the surroundings on different ferrite materials has shown chemical and strong microcrystalline structure modifications. We report the electrical and optical properties of such a source by high voltage measurements, time integrated and time resolved VUV optical spectroscopy and frame photographs. An observation of the plasma expansion with the formation and the propagation of a blast wave (1.8 km/s) is presented for the first time. The possibility of a peak intensity shift of VUV radiation to shorter wavelengths is discussed. C1 FAC SCI LUMINY,CNRS,URA 783,ETATS CONDENSES GRP,F-13288 MARSEILLE 9,FRANCE. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP SENTIS, ML (reprint author), INST MECAN FLUIDES MARSEILLE,CNRS,UM 34,1 RUE HONNORAT,F-13003 MARSEILLE,FRANCE. RI Dom, Rekha/B-7113-2012 NR 11 TC 2 Z9 2 U1 0 U2 0 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 MAY PY 1993 VL 69 IS 1-4 BP 185 EP 192 DI 10.1016/0169-4332(93)90502-3 PG 8 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA LA076 UT WOS:A1993LA07600032 ER PT J AU SIRIWARDANE, RV POSTON, JA AF SIRIWARDANE, RV POSTON, JA TI CHARACTERIZATION OF COPPER OXIDES, IRON-OXIDES, AND ZINC COPPER FERRITE DESULFURIZATION SORBENTS BY X-RAY PHOTOELECTRON-SPECTROSCOPY AND SCANNING ELECTRON-MICROSCOPY SO APPLIED SURFACE SCIENCE LA English DT Article ID METHANOL-SYNTHESIS CATALYSTS; TRANSITION-METAL COMPOUNDS; SURFACE CHARACTERIZATION; CUO; ZNO; XPS; PHOTOIONIZATION; CU2O AB Characterization of copper oxides, iron oxides, and zinc copper ferrite desulfurization sorbents was performed by X-ray photoelectron spectroscopy and scanning electron microscopy/energy-dispersive spectroscopy at temperatures of 298 to 823 K. Analysis of copper oxides indicated that the satellite structure of the Cu2p region was absent in the Cu(I) state but was present in the Cu(II) state. Reduction of CuO at room temperature was observed when the ion gauge was placed close to the sample. The satellite structure was absent in all the copper oxides at 823 K in vacuum. Differentiation of the oxidation state of copper utilizing both Cu(L3M4,5M4,5) X-ray-induced Auger lines and Cu2p satellite structure, indicated that the copper in zinc copper ferrite was in the +1 oxidation state at 823 K. This + 1 state of copper was not significantly changed after exposure to H-2, CO, and H2O. There was an increase in Cu/Zn ratio and a decrease in Fe/Zn ratio on the surface of zinc copper ferrite at 823 K compared to that at room temperature. These conditions of copper offered the best sulfidation equilibrium for the zinc copper ferrite desulfurization sorbent. Analysis of iron oxides indicated that there was some reduction of both Fe2O3 and FeO at 823 K. The iron in zinc copper ferrite was similar to that of Fe2O3 at room temperature but there was some reduction of this Fe(III) state to Fe(II) at 823 K. This reduction was more enhanced in the presence of H2 and CO. Reduction to Fe(II) may not be desirable for the lifetime of the sorbent. RP SIRIWARDANE, RV (reprint author), US DOE,MORGANTOWN ENERGY TECHNOL CTR,POB 880,MORGANTOWN,WV 26507, USA. RI Dom, Rekha/B-7113-2012 NR 20 TC 44 Z9 44 U1 1 U2 25 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 MAY PY 1993 VL 68 IS 1 BP 65 EP 80 DI 10.1016/0169-4332(93)90216-X PG 16 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA LA319 UT WOS:A1993LA31900006 ER PT J AU KRAUTER, PW AF KRAUTER, PW TI MICRONUCLEUS INCIDENCE AND HEMATOLOGICAL EFFECTS IN BULLFROG TADPOLES (RANA-CATESBEIANA) EXPOSED TO 2-ACETYLAMINOFLUORENE AND 2-AMINOFLUORENE SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID PERIPHERAL-BLOOD ERYTHROCYTES; INVIVO GENOTOXICITY; PLEURODELES-WALTL; NEWT LARVAE; FISH; LYMPHOCYTES; INDUCTION; EFFLUENT; WATER; CELLS AB The micronucleus technique used with Rana catesbeiana tadpoles is useful for the evaluation of aromatic amine toxicity. When exposed to increasing concentrations of the aromatic amine 2-acetylaminofluorene (2-AAF 1 x 10(-8) M to 5 X 10(-5) M), R. catesbeiana tadpoles responded with an increasing frequency of micronuclei (MN) in the peripheral blood. Micronuclei increased fourfold with the 5 x 10(-5) M 2-AAF exposure. Micronuclei frequency significantly increased with concentrations as low as 5 x 10(-8) M. The time from initial mutagen exposure to the time of maximum number of MN present in the peripheral blood occurred at two separate times: 2 d and 14 d after exposure. The occurrence of two MN frequency peaks may be due to the presence of two erythrocyte populations from two hemopoietic sources (liver and kidneys) in young tadpoles. The occurrence of immature erythrocytes, as well as general degenerative changes [such as fragmentation (schistocytosis)] in the erythrocytes and vacuolated cytoplasms suggested 2-AAF may contribute to hemolytic anemia effects. 2-AAF also increased the frequency of rubricytes found in the peripheral blood, but had no significant effect on the hematocrit values of animals exposed to concentrations up to 1 x 10(-5) M. The tadpoles may have been producing rubricytes to replace the damaged red blood cells (RBCs). The direct-acting mutagen 2-aminofluorene (2-AF) was considerably more toxic to peripheral RBCs than the indirect-acting 2-AAF. Hematocrit values of the 2-AF (1 x 10(-5) M)-exposed tadpoles declined severely (from 22 to 10%) because of a significant increase in osmotic fragility of erythrocytes, resulting in cell lysis. The general nature of these stress responses indicates that measurement of tadpole blood characteristics, including erythrocyte morphology, may provide a sensitive means of early warning for some water quality changes adverse to aquatic life. RP KRAUTER, PW (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT ENVIRONM PROTECT,DIV ENVIRONM RESTORAT,POB 808,L-619,LIVERMORE,CA 94550, USA. NR 37 TC 10 Z9 12 U1 2 U2 6 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD MAY PY 1993 VL 24 IS 4 BP 487 EP 493 PG 7 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA LA322 UT WOS:A1993LA32200013 PM 8507104 ER PT J AU AUSTIN, MA NEWMAN, B SELBY, JV EDWARDS, K MAYER, EJ KRAUSS, RM AF AUSTIN, MA NEWMAN, B SELBY, JV EDWARDS, K MAYER, EJ KRAUSS, RM TI GENETICS OF LDL SUBCLASS PHENOTYPES IN WOMEN TWINS - CONCORDANCE, HERITABILITY, AND COMMINGLING ANALYSIS SO ARTERIOSCLEROSIS AND THROMBOSIS LA English DT Article DE CHOLESTEROL; CORONARY HEART DISEASE; GENETICS; HERITABILITY; LDL; TWINS ID LOW-DENSITY-LIPOPROTEIN; CORONARY-ARTERY DISEASE; APOLIPOPROTEIN-B; MOLECULAR-WEIGHT; HEART-DISEASE; RISK-FACTORS; NHLBI TWIN; PATTERNS; SUBFRACTION; HETEROGENEITY AB Low density lipoprotein (LDL) subclass phenotype B, characterized by a predominance of small LDL as determined by gradient gel electrophoresis, has been associated with increased risk of coronary heart disease and an atherogenic lipoprotein profile. Previous studies employing complex segregation analysis have demonstrated a major, single gene effect on the inheritance of this phenotype in families. Recently, linkage between this phenotype and variation at the LDL receptor locus on chromosome 19 has been reported. However, variation in LDL subclass phenotypes has also been associated with age, gender, diabetes status, beta-blocker medication, and diet. The present study further evaluates the relative importance of genetic and nongenetic influences on LDL subclass phenotypes and on LDL peak particle diameter (as a reflection of the size of the major LDL subclass) in monozygotic and dizygotic women twin pairs. The analysis is based on 203 monozygotic and 145 dizygotic pairs of adult female twins who participated in the second examination of the Kaiser Permanente Women Twins Study. The average age was 51 years at this exam and 90% were white. Concordance analysis revealed that monozygotic cotwins shared LDL subclass phenotypes more frequently than dizygotic cotwins, and this was confirmed using logistic regression analysis after controlling for potential confounding factors. Heritability analyses suggested that approximately one third to one half of the variation in LDL peak particle diameter, a continuous variable reflecting LDL size, could be attributed to genetic influences. Commingling analysis of the frequency distribution of LDL peak particle diameter identified three distinct subgroups of subjects, one of which corresponded to those subjects with LDL subclass phenotype B. This result could reflect the presence of a major gene effect on LDL size. These analyses in women twins demonstrate substantial genetic influences on LDL size heterogeneity, confirming previous studies in families. In addition, significant nongenetic factors are also apparently operating and thus could provide opportunities for targeted intervention to reduce coronary heart disease risk. C1 KAISER PERMANENTE MED CARE PROGRAM,DIV RES,OAKLAND,CA. LAWRENCE BERKELEY LAB,DIV RES MED & RADIAT BIOPHYS,MOLEC MED RES PROGRAM,BERKELEY,CA 94720. UNIV N CAROLINA,SCH PUBL HLTH,DEPT EPIDEMIOL,CHAPEL HILL,NC 27514. RP AUSTIN, MA (reprint author), UNIV WASHINGTON,SCH PUBL HLTH & COMMUNITY MED,DEPT EPIDEMIOL,SC-36,SEATTLE,WA 98195, USA. FU NHLBI NIH HHS [HL-38760, HL-41830] NR 44 TC 73 Z9 73 U1 0 U2 0 PU AMER HEART ASSOC PI DALLAS PA 7272 GREENVILLE AVENUE, DALLAS, TX 75231-4596 SN 1049-8834 J9 ARTERIOSCLER THROMB JI Arterioscler. Thromb. PD MAY PY 1993 VL 13 IS 5 BP 687 EP 695 PG 9 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA LB036 UT WOS:A1993LB03600009 PM 8485120 ER PT J AU OLIVIER, SS PRIMACK, JR BLUMENTHAL, GR DEKEL, A AF OLIVIER, SS PRIMACK, JR BLUMENTHAL, GR DEKEL, A TI SIGNIFICANT CLUSTER CORRELATIONS AT 30 H(-1) MPC - CAN STANDARD MODELS BE RULED OUT SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMOLOGY, THEORY; DARK MATTER; GALAXIES, CLUSTERING ID COLD DARK MATTER; LARGE-SCALE STRUCTURE; RICH CLUSTERS; ABELL CLUSTERS; EXTRAGALACTIC OBJECTS; STATISTICAL-ANALYSIS; CROSS-CORRELATION; GALAXY CLUSTERS; UNIVERSE; CATALOGS AB We compute the cluster autocorrelation function, xi(c)(r), of an extended, complete sample of 220 rich (R greater-than-or-equal-to 1) Abell clusters with measured redshifts. We correct for projection contamination and pay special attention to estimating the random errors, aiming at rejecting certain theoretical models. While the observed xi(c) in the range r < 20 h-1 Mpc is in agreement with the predictions of CDM and textures models, we find an excess over both theories in the range 20 h-1 M pc less-than-or-equal-to r less-than-or-equal-to 40 h-1 Mpc, significant at beyond the 3 sigma level. Assuming that the observed xi(c) below 30 h-1 Mpc represents the true correlations, the hypothesis that xi(c) vanishes right beyond this scale can be rejected with similar confidence. These results are in agreement with our earlier findings from the angular correlation function of the complete Abell and ACO catalogs. Possible remaining biases and ways out for these models are discussed. C1 UNIV CALIF SANTA CRUZ,SANTA CRUZ INST PARTICLE PHYS,SANTA CRUZ,CA 95064. UNIV CALIF SANTA CRUZ,UNIV CALIF OBSERV LICK OBSERV,BOARD STUDIES ASTRON & ASTROPHYS,SANTA CRUZ,CA 95064. HEBREW UNIV JERUSALEM,RACAH INST PHYS,IL-91904 JERUSALEM,ISRAEL. UNIV CALIF SANTA CRUZ,BOARD STUDIES PHYS,SANTA CRUZ,CA 95064. INST ASTROPHYS,F-75014 PARIS,FRANCE. RP OLIVIER, SS (reprint author), LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550, USA. NR 39 TC 15 Z9 15 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 MAY 1 PY 1993 VL 408 IS 1 BP 17 EP 24 DI 10.1086/172565 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KY810 UT WOS:A1993KY81000002 ER PT J AU LUO, XC SCHRAMM, DN AF LUO, XC SCHRAMM, DN TI KURTOSIS, SKEWNESS, AND NON-GAUSSIAN COSMOLOGICAL DENSITY PERTURBATIONS SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMOLOGY, THEORY; LARGE-SCALE STRUCTURE OF UNIVERSE ID LARGE-SCALE STRUCTURE; FLUCTUATION SPECTRA; COSMIC STRUCTURE; EVOLUTION; CLUSTERS; GALAXIES; UNIVERSE; TEXTURE AB Cosmological topological defects as well as some nonstandard inflation models can give rise to non-Gaussian density perturbations. Skewness and kurtosis are the third and fourth moments that measure the deviation of a distribution from a Gaussian. Measurement of these moments for the cosmological density field and for the microwave background temperature anisotropy can provide a test of the Gaussian nature of the primordial fluctuation spectrum. In the case of the density field, the importance of measuring the kurtosis is stressed since it will be preserved through the weakly nonlinear gravitational evolution epoch. Current constraints on skewness and kurtosis of primeval perturbations are obtained from the observed density contrast deltarho/rho on small scales and from recent COBE observations of temperature anisotropies on large scales. It is also shown how, in principle, future microwave anisotropy experiments might be able to reveal the initial skewness and kurtosis. It is shown that present data argue that if the initial spectrum is adiabatic, then it is probably Gaussian, but non-Gaussian isocurvature fluctuations are still allowed, and these are what topological defects provide. C1 NASA,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. RP LUO, XC (reprint author), UNIV CHICAGO,5640 S ELLIS AVE,CHICAGO,IL 60637, USA. NR 43 TC 39 Z9 39 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 MAY 1 PY 1993 VL 408 IS 1 BP 33 EP 42 DI 10.1086/172567 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KY810 UT WOS:A1993KY81000004 ER PT J AU ARONS, J AF ARONS, J TI MAGNETIC-FIELD TOPOLOGY IN PULSARS SO ASTROPHYSICAL JOURNAL LA English DT Article DE GAMMA-RAYS, BURSTS; PULSARS, GENERAL; STARS, MAGNETIC FIELDS; STARS, NEUTRON ID GAMMA-RAY BURSTS; NEUTRON-STAR; POLAR CAPS; CYCLOTRON; DECAY; ZONE; SCATTERING; ACCRETION; EMISSION; SPECTRA AB It is shown that the location of the spin-up line in the P - P diagram is sensitive to the presence of large-scale magnetic anomalies (quadrupole, ...) and that one can usefully constrain the surface strength of such fields to be not more than approximately 40% of the surface strength of the dipole in spun-up pulsars. This constraint shows that if gamma-ray bursters are related to old Galactic neutron stars, those with strong cyclotron lines cannot have had the same magnetic history as spun-up millisecond pulsars. The spin-up line also constrains models in which the magnetic field is a single intense surface pole, although the present data set has too few very short period pulsars with measured P to provide useful information. The spin-up line is insensitive to magnetic fields in which the dipole is formed by the superposition of many crustal clumps, as in some magnetic evolution scenarios. However, polarization and beaming morphology of the radio emission in longer period pulsars can be used to argue that the near-zone fields of normal pulsars are not composed of such magnetic hair and could be used in the millisecond pulsars, once data become available for a substantial number of these stars. An interesting byproduct of the analysis is the conclusion that if the disks confining the magnetospheres during the spin-up phase are largely diagmagnetic and entrain the stellar magnetic field only in a boundary layer whose thickness is comparable to that of the disk, the inner edges of such disks are located at the radius expected in spherical accretion. The fact that the resulting spin-up line for a dipolar magnetosphere agrees so well with the data is used to support the idea that the disk-magnetosphere interaction is fundamentally similar to that occurring between the solar wind and planetary magnetospheres, where in spite of the strong dissipation, the exterior plasma is dynamically excluded from the magnetosphere as if it is diamagnetic. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550. LAWRENCE LIVERMORE NATL LAB,PLASMA PHYS RES INST,LIVERMORE,CA 94550. RP ARONS, J (reprint author), UNIV CALIF BERKELEY,DEPT ASTRON,601 CAMPBELL HALL,BERKELEY,CA 94720, USA. NR 56 TC 74 Z9 74 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 MAY 1 PY 1993 VL 408 IS 1 BP 160 EP 166 DI 10.1086/172576 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KY810 UT WOS:A1993KY81000013 ER PT J AU CHEN, KY MIDDLEDITCH, J RUDERMAN, M AF CHEN, KY MIDDLEDITCH, J RUDERMAN, M TI LOW-MASS X-RAY BINARIES AND MILLISECOND PULSARS IN GLOBULAR-CLUSTERS SO ASTROPHYSICAL JOURNAL LA English DT Article DE BINARIES, GENERAL; GLOBULAR CLUSTERS, GENERAL; PULSARS, GENERAL; X-RAYS, STARS ID DISCOVERY AB Globular clusters harbor many millisecond pulsars and 10 bright low-mass X-ray binary systems. It has been generally believed that almost all millisecond pulsars are spun up by accretion from a companion star during a (progenitor) low-mass X-ray binary (LMXB) phase. However, most of the short-period millisecond pulsars are found in the apparently younger globular clusters, which have much lower core densities than those characteristic of the apparently older globulars containing the majority of the LMXBs. The vast majority of the globular LMXBs are X-ray burst sources, and among them there are no bright sources similar to those in the Galactic disk, such as Sco X-1, Cyg X-2, and GX 5-1. Furthermore, the radio pulse properties of the very short period millisecond pulsars in globular clusters differ from those of pulsars spun up in the Galactic disk, such as PSR 1937 + 21 and PSR 1957 + 20. Only the properties of the latter class are consistent with what is expected for the spin-up scenario. We argue that, in most globular cluster LMXBs, the neutron stars were formed spinning rapidly, and are likely to be the descendants, rather than the progenitors, of weakly magnetized millisecond pulsars. C1 LOS ALAMOS NATL LAB,DIV COMP & COMMUN,LOS ALAMOS,NM 87545. COLUMBIA UNIV,DEPT PHYS,NEW YORK,NY 10027. COLUMBIA UNIV,COLUMBIA ASTROPHYS LAB,NEW YORK,NY 10027. RP CHEN, KY (reprint author), LOS ALAMOS NATL LAB,MS B288,LOS ALAMOS,NM 87545, USA. NR 28 TC 16 Z9 16 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 MAY 1 PY 1993 VL 408 IS 1 BP L17 EP L20 DI 10.1086/186820 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KY811 UT WOS:A1993KY81100005 ER PT J AU PITOVRANOV, SE FEDOROV, VV EDWARDS, LL AF PITOVRANOV, SE FEDOROV, VV EDWARDS, LL TI OPTIMAL SAMPLER SITING FOR ATMOSPHERIC TRACER EXPERIMENTS TAKING INTO ACCOUNT UNCERTAINTIES IN THE WIND-FIELD SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE OPTIMAL NETWORK DESIGN; WIND SPEED; WIND DIRECTION; TRACER EXPERIMENT AB The problem of sampling sites for atmospheric tracer experiments were considered in Fedorov and Pitovranov (working paper WP-85-65, International Institute for Applied Systems Analysis, Laxenburg, Austria, 1988). There it was assumed that the wind direction during an experimental tracer release could be accurately predetermined and would remain constant for the duration of the experiment. In general, this assumption of a constant wind field is not met. In this work we develop an approach which overcomes this deficiency. The monitoring network design problem is considered for cases which include prior uncertain wind fields during a designed experiment. C1 CENT LAB SOCIAL & ECON METHODS,MOSCOW 117312,RUSSIA. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP PITOVRANOV, SE (reprint author), MOSCOW SYST STUDIES INST,MOSCOW 117312,RUSSIA. NR 14 TC 0 Z9 4 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD MAY PY 1993 VL 27 IS 7 BP 1053 EP 1059 DI 10.1016/0960-1686(93)90140-T PG 7 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA LG417 UT WOS:A1993LG41700001 ER PT J AU TENNE, R EHERMAN, K MAHALU, D PEISACH, M KAUTEK, W WOLD, A MATSON, R WALDECK, DH AF TENNE, R EHERMAN, K MAHALU, D PEISACH, M KAUTEK, W WOLD, A MATSON, R WALDECK, DH TI THE WSE2 TUNGSTEN-OXIDE INTERFACE - STRUCTURE AND PHOTOLUMINESCENCE SO BERICHTE DER BUNSEN-GESELLSCHAFT-PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article DE LUMINESCENCE; PHOTOELECTROCHEMISTRY; SEMICONDUCTORS; SURFACES ID TRANSITION-METAL DICHALCOGENIDES; RECOMBINATION CENTERS; SURFACE PASSIVATION; ELECTRODES; EFFICIENCY; SILICON; MOS2; WO3; PHOTOCORROSION; BOMBARDMENT AB A ''mixed'' surface of WSe2, which contains both the parallel-to c and perpendicular-to c facets was produced by mechanical indentation, followed by photoelectrochemical etching, and chemical cleaning. This surface was shown to exhibit low surface recombination velocity, and consequently high solar to electrical conversion efficiency, in the past. Using O-18 as a tracer for nuclear activation analysis it is shown that, after the above surface treatment, the surface of the parallel-to c facet is covered with a thin (3 - 5 monolayers) film of tungsten oxide. The structure of the crystalline oxide phases that comprise the tungsten-oxide/WSe2 interface are investigated with powder X-ray diffraction. X-ray photoelectron spectroscopy is used to study the chemical bonding at the interface. A model is proposed to explain the absence of surface recombination at this interface. A strong above the bandgap luminescence is observed from parallel-to c facets of ''mixed'' surfaces, and from crystal edges (parallel-to c) which were allowed to ''age'' for a few weeks in the air. The origin of this luminescence was investigated in some detail, and a mechanism, involving partially oxidized parallel-to c surface which possibly leads to quantum confinement of excitons in parallel-to c edges of WSe2, is proposed. C1 NATL ACCELERATOR LAB,FAURE 7212,SOUTH AFRICA. FED INST MAT RES & TESTING,CHEM SURFACE TECHNOL LAB,W-1000 BERLIN 33,GERMANY. BROWN UNIV,DEPT CHEM,PROVIDENCE,RI 02912. NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. UNIV PITTSBURGH,DEPT CHEM,PITTSBURGH,PA 15260. RP TENNE, R (reprint author), WEIZMANN INST SCI,DEPT MAT & INTERFACES,IL-76100 REHOVOT,ISRAEL. NR 59 TC 7 Z9 7 U1 1 U2 31 PU VCH PUBLISHERS INC PI DEERFIELD BEACH PA 303 NW 12TH AVE, DEERFIELD BEACH, FL 33442-1788 SN 0005-9021 J9 BER BUNSEN PHYS CHEM JI Ber. Bunsen-Ges. Phys. Chem. Chem. Phys. PD MAY PY 1993 VL 97 IS 5 BP 702 EP 709 PG 8 WC Chemistry, Physical SC Chemistry GA LK005 UT WOS:A1993LK00500009 ER PT J AU WANG, TH YANG, WK HOYT, PR CHANG, LY SAVIN, TJ AF WANG, TH YANG, WK HOYT, PR CHANG, LY SAVIN, TJ TI EFFECT OF MATERNAL AGING ON TRANSGENE HERITABILITY IN TRANSGENIC FOUNDER MICE DERIVED FROM ZYGOTES MICROINJECTED WITH RETROVIRAL LONG TERMINAL REPEAT-CONTAINING RECOMBINANT DEOXYRIBONUCLEIC-ACID SO BIOLOGY OF REPRODUCTION LA English DT Article ID HUMAN-GENE THERAPY; GERM-LINE; MOUSE; ELEMENTS; DNA; GENOME; CLONE AB To determine the stability of artificially introduced recombinant DNA in the life, founder mice derived from fertilized eggs injected with retroviral long-terminal-repeat-containing recombinant DNAs were mated with congenic FVB/N mice. Tail DNA of all progeny were screened and restriction fragment patterns of the transgenes were examined. Litter size and percentage of transgene transmission at various reproductive age periods were analyzed. Microinjection of 1737 eggs with four different recombinant DNAs resulted in 12 female and 11 male transgenic mice; 2 males were sterile and the remaining 21 mice served as founders to produce 1087 F1 progeny. With increasing parental age, litter size decreased generally. The percentage of progeny inheriting the transgenes declined markedly with increasing aging of 4 female founders; this aging effect was not observed in male founders (p < 0.005). No apparent change in transgenes was detected in progeny from late reproductive stages. C1 OAK RIDGE NATL LAB,DIV BIOL,BEAR CREEK RD,POB 2009,OAK RIDGE,TN 37831. UNIV TENNESSEE,OAK RIDGE GRAD SCH BIOMED SCI,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT MICROBIOL,KNOXVILLE,TN 37996. FU NCI NIH HHS [P32-CA-09336]; NIEHS NIH HHS [YO1-ES-4-0118] NR 35 TC 4 Z9 4 U1 0 U2 0 PU SOC STUDY REPRODUCTION PI MADISON PA 1603 MONROE ST, MADISON, WI 53711-2021 SN 0006-3363 J9 BIOL REPROD JI Biol. Reprod. PD MAY PY 1993 VL 48 IS 5 BP 1104 EP 1112 DI 10.1095/biolreprod48.5.1104 PG 9 WC Reproductive Biology SC Reproductive Biology GA LE636 UT WOS:A1993LE63600021 PM 8097631 ER PT J AU ROLES, KA XENOPOULOS, A WUNDERLICH, B AF ROLES, KA XENOPOULOS, A WUNDERLICH, B TI HEAT-CAPACITIES OF SOLID POLY(AMINO ACID)S .2. THE REMAINING POLYMERS SO BIOPOLYMERS LA English DT Article ID NORMAL COORDINATE ANALYSIS; LINEAR MACROMOLECULES; THERMODYNAMIC PROPERTIES; THERMAL VARIATIONS; AQUEOUS-SOLUTION; L-ALANINE; DENATURATION; PROTEINS; WATER; POLY(L-VALINE) AB In the first paper heat capacities C(p), of polyglycine, poly (L-alanine), and poly (L-valine) were analyzed using approximate group vibrations and fitting the C(p) contributions of the skeletal vibrations to a two-parameter Tarasov function. In this second paper all other poly (amino acid) s are similarly analyzed. Heat capacities were measured by differential scanning calorimetry in the temperature range of 230-390 K for Poly (L-leucine), poly (L-serine), poly (sodium-L-aspartate), poly (sodium-L-glutamate), poly (L-asparagine), poly (L-phenylalanine), poly(L-tyrosine), poly(L-methionine), poly(L-tryptophane), poly(L-proline),poly(L-lysine.HBr), poly(L-histidine), poly(L-histidine-HCl), and poly(L-arginine.HCl). Good agreement exists between experiment and calculation. Predictions of heat capacities were made for all not-measured poly (amino acid) s. Enthalpies, entropies, and Gibbs functions for the solid state have been derived. C1 OAK RIDGE NATL LAB, DIV CHEM, OAK RIDGE, TN 37831 USA. UNIV TENNESSEE, DEPT CHEM, KNOXVILLE, TN 37996 USA. NR 65 TC 44 Z9 44 U1 3 U2 14 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0006-3525 EI 1097-0282 J9 BIOPOLYMERS JI Biopolymers PD MAY PY 1993 VL 33 IS 5 BP 753 EP 768 DI 10.1002/bip.360330505 PG 16 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA KZ440 UT WOS:A1993KZ44000004 ER PT J AU DUFFY, PB AF DUFFY, PB TI GLOBAL WARMING - A REDUCED THREAT - COMMENT SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Letter RP DUFFY, PB (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV ATMOSPHER & GEOPHYS SCI,LIVERMORE,CA 94550, USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAY PY 1993 VL 74 IS 5 BP 855 EP 855 PG 1 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA LD116 UT WOS:A1993LD11600011 ER PT J AU STURCHIO, NC WILLIAMS, SN SANO, Y AF STURCHIO, NC WILLIAMS, SN SANO, Y TI THE HYDROTHERMAL SYSTEM OF VOLCAN PURACE, COLOMBIA SO BULLETIN OF VOLCANOLOGY LA English DT Article DE VOLCAN PURACE; COLOMBIA; HYDROTHERMAL SYSTEM; VOLCANIC GASES; HE-ISOTOPES; S-ISOTOPES AB This paper presents chemical and isotopic data for thermal waters, gases and S deposits from Volcan Purace (summit elevation approximately 4600 m) in SW Colombia. Hot gas discharges from fumaroles in and around the summit crater, and thermal waters discharge from three areas on its flanks. The waters from all areas have deltaD values of -75 +/- 1, indicating a single recharge area at high elevation on the volcano. Air-corrected values of He-3/He-4 in thermal waters range from 3.8 to 6.7 R(A), and approach those for crater fumarole gas (6.1-7.1 R(A)), indicating widespread addition of magmatic volatiles. An economic S deposit (El Vinagre) is being mined in the Rio Vinagre fault zone at 3600 m elevation. Sulfur isotopic data are consistent with a magmatic origin for S species in thermal waters and gases, and for the S ore deposit. Isotopic equilibration between S species may have occurred at 220 +/- 40-degrees-C, which overlaps possible equilibration temperatures (170 +/- 40-degrees-C) determined by a variety of other geothermometers for neutral thermal waters. Apparent CH4-CO2 equilibration temperatures for gases from thermal springs (400 +/- 50-degrees-C) and crater fumaroles (520 +/- 60-degrees-C) reflect higher temperatures deeper in the system. Hot magmatic gas ascending through the Rio Vinagre fault zone is though to have precipitated S and generated thermal waters by interaction with descending meteoric waters. RP STURCHIO, NC (reprint author), ARGONNE NATL LAB,CMT-205,ARGONNE,IL 60439, USA. NR 0 TC 12 Z9 12 U1 1 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0258-8900 J9 B VOLCANOL JI Bull. Volcanol. PD MAY PY 1993 VL 55 IS 4 BP 289 EP 296 DI 10.1007/BF00624356 PG 8 WC Geosciences, Multidisciplinary SC Geology GA LD314 UT WOS:A1993LD31400004 ER PT J AU WEST, DC DOYLE, TW THARP, ML BEAUCHAMP, JJ PLATT, WJ DOWNING, DJ AF WEST, DC DOYLE, TW THARP, ML BEAUCHAMP, JJ PLATT, WJ DOWNING, DJ TI RECENT GROWTH INCREASES IN OLD-GROWTH LONGLEAF PINE SO CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE LA English DT Article ID ATMOSPHERIC CARBON-DIOXIDE; LIQUIDAMBAR-STYRACIFLUA; TAEDA SEEDLINGS; CO2 ENRICHMENT; UNITED-STATES; COMPETITION; CLIMATE AB Longleaf pine (Pinus palustris Mill.) tree-ring data were obtained from an old-growth stand located in Thomas County, Georgia. The tree-ring chronology from the pine stand is composed of a collection of cores extracted from 26 trees ranging in age from approximately 100 to 400 years. These cores were prepared, dated, and measured, and the resulting data were examined with dendrochronological and statistical techniques. Beginning in approximately 1950 and continuing to the present, annual increments of all age classes examined in this study have increased. resulting in an average annual ring increment approximately 40% greater in 1987 than in 1950. When compared with expected annual increment, the increase for 100- to 150-year-old trees is approximately 45%, while the increase for 200- to 400-year-old trees is approximately 35%. In terms of stand-level aboveground biomass accumulation, the increased growth has resulted in approximately 5% more biomass than expected. The increased growth cannot be explained by disturbance; stand history; or trends in precipitation, temperature, or Palmer drought severity index over the last 57 years. Increased atmospheric CO2 is a possible explanation for initiation of the observed trend, while SO(x) and NO(x) may be augmenting continuation of this phenomenon. C1 US FISH & WILDLIFE SERV,LAFAYETTE,LA 70506. OAK RIDGE NATL LAB,DIV COMP APPLICAT,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,DIV ENGN PHYS & MATH,OAK RIDGE,TN 37831. LOUISIANA STATE UNIV,DEPT BOT,BATON ROUGE,LA 70801. RP WEST, DC (reprint author), OAK RIDGE NATL LAB,DIV VET MED & BIOMED SCI,OAK RIDGE,TN 37831, USA. NR 49 TC 19 Z9 19 U1 2 U2 10 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 MAY PY 1993 VL 23 IS 5 BP 846 EP 853 DI 10.1139/x93-110 PG 8 WC Forestry SC Forestry GA LQ390 UT WOS:A1993LQ39000010 ER PT J AU PISARSKI, RD AF PISARSKI, RD TI MEDLEY IN FINITE-TEMPERATURE FIELD-THEORY SO CANADIAN JOURNAL OF PHYSICS LA English DT Article; Proceedings Paper CT WORKSHOP ON PERTURBATIVE METHODS IN HOT GAUGE THEORIES CY JUL 20-25, 1992 CL UNIV WINNIPEG, WINNIPEG, CANADA HO UNIV WINNIPEG ID QUARK-GLUON PLASMA; HOT GAUGE-THEORIES; TRANSPORT-COEFFICIENTS; DAMPING RATE; QUANTUM CHROMODYNAMICS; THERMAL-EQUILIBRIUM; INTERFACE TENSION; ENERGETIC GLUONS; QCD PLASMA; DEPENDENCE AB Three subjects in thermal field theory are discussed; why in SU(N) gauge theories the Z(N) symmetry is broken at high (instead of low) temperature, the possible singularity structure of gauge-variant propagators, and the problem of how to compute the viscosity from the Kubo formula. RP PISARSKI, RD (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 48 TC 3 Z9 3 U1 0 U2 0 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4204 J9 CAN J PHYS JI Can. J. Phys. PD MAY-JUN PY 1993 VL 71 IS 5-6 BP 280 EP 284 PG 5 WC Physics, Multidisciplinary SC Physics GA LT499 UT WOS:A1993LT49900014 ER PT J AU HOLLY, EA CRESS, RD AHN, DK ASTON, DA KRISTIANSEN, JJ WU, RK FELTON, JS AF HOLLY, EA CRESS, RD AHN, DK ASTON, DA KRISTIANSEN, JJ WU, RK FELTON, JS TI DETECTION OF MUTAGENS IN CERVICAL-MUCUS IN SMOKERS AND NONSMOKERS SO CANCER EPIDEMIOLOGY BIOMARKERS & PREVENTION LA English DT Article ID HUMAN-URINE; INTRAEPITHELIAL NEOPLASIA; CIGARETTE SMOKERS; BODY-FLUIDS; AMES TEST; NICOTINE; SMOKING; CANCER; CARCINOGENS; COTININE AB The Salmonella mutagenicity test was used to analyze cervical mucus specimens from 364 smokers and 333 nonsmokers to determine whether the association between smoking and mutagenic cervical mucus that we reported previously among women diagnosed with dysplasia would apply to a larger group of healthy women (E. A. Holly et al., J. Natl. Cancer Inst., 76: 983-986, 1986). Women smokers and nonsmokers between the ages of 18 and 49 who attended eleven clinics and physicians' offices in the San Francisco Bay area for a routine Pap smear were examined to determine whether smokers were more likely to have mutagenic substances in their cervical mucus. About 4% of smokers and 8% of nonsmokers had positive mutagenicity test results (P = 0.02). Cervical mucus with a large number of microorganisms was more likely to have a positive mutagenicity test result than that with fewer microorganisms (test for trend, P = 0.01). Mutagenicity results varied by race and clinic location but were not associated with smoking behavior, sexual behavior, gynecological diagnosis, or diet. Further work is needed to develop methods to detect mutagens in specific body fluids. C1 LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,LIVERMORE,CA 94550. RP HOLLY, EA (reprint author), UNIV CALIF SAN FRANCISCO,SCH MED,DEPT EPIDEMIOL & BIOSTATIST,1388 SUTTER ST,SUITE 920,SAN FRANCISCO,CA 94109, USA. FU NCI NIH HHS [CA42440] NR 33 TC 10 Z9 10 U1 0 U2 0 PU AMER ASSOC CANCER RESEARCH PI PHILADELPHIA PA PUBLIC LEDGER BLDG, SUITE 816, 150 S. INDEPENDENCE MALL W., PHILADELPHIA, PA 19106 SN 1055-9965 J9 CANCER EPIDEM BIOMAR JI Cancer Epidemiol. Biomarkers Prev. PD MAY-JUN PY 1993 VL 2 IS 3 BP 223 EP 228 PG 6 WC Oncology; Public, Environmental & Occupational Health SC Oncology; Public, Environmental & Occupational Health GA LB421 UT WOS:A1993LB42100008 PM 8318874 ER PT J AU JONES, IM MOORE, DH THOMAS, CB THOMPSON, CL STROUT, CL BURKHARTSCHULTZ, K AF JONES, IM MOORE, DH THOMAS, CB THOMPSON, CL STROUT, CL BURKHARTSCHULTZ, K TI FACTORS AFFECTING HPRT MUTANT FREQUENCY IN T-LYMPHOCYTES OF SMOKERS AND NONSMOKERS SO CANCER EPIDEMIOLOGY BIOMARKERS & PREVENTION LA English DT Article ID HUMAN PERIPHERAL-BLOOD; POLYMERASE CHAIN-REACTION; BREAST-CANCER PATIENTS; MUTATION ASSAY; CLONING ASSAY; LUNG-CANCER; CIRCULATING LYMPHOCYTES; XERODERMA-PIGMENTOSUM; MOLECULAR ANALYSES; SOMATIC MUTATIONS AB The frequency of thioguanine-resistant, hypoxanthine phosphoribosyltransferase-deficient lymphocytes in the peripheral blood of human subjects was used to study the genotoxic effects of smoking. Sixty-two nonsmokers and 58 smokers, aged 19 to 45 years with average ages of 30 and 32 years, respectively, and with no other known exposures, were studied using an in vitro assay of the frequency of mutant lymphocyte clones. Analysis of variance explained 68% of the variation in the mutant frequencies. Mutant frequency was dependent upon lymphocyte cloning efficiency, length of smoking history, age, and interactions between these variables. Four nonsmokers and three smokers had high mutant frequencies that were not explained by these variables. Mutant frequencies were inversely related to lymphocyte cloning efficiencies; the effect was twice as great for smokers as for nonsmokers. The time-dependent effect of smoking dominated, with mutant frequency increasing 10%/year of smoking as compared with an independent 1%/year of age. Smoking had a greater effect on young smokers' lymphocytes. Heterogeneity of mutant frequency among both smokers and nonsmokers and its implications for use of lymphocyte mutation assays as biomarkers are discussed. C1 NIEHS,DIV BIOMETRY & RISK ASSESSMENT,RES TRIANGLE PK,NC 27709. RP JONES, IM (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,L-452,POB 808,LIVERMORE,CA 94551, USA. FU NIEHS NIH HHS [Y01-ES-80171] NR 67 TC 43 Z9 43 U1 0 U2 0 PU AMER ASSOC CANCER RESEARCH PI PHILADELPHIA PA PUBLIC LEDGER BLDG, SUITE 816, 150 S. INDEPENDENCE MALL W., PHILADELPHIA, PA 19106 SN 1055-9965 J9 CANCER EPIDEM BIOMAR JI Cancer Epidemiol. Biomarkers Prev. PD MAY-JUN PY 1993 VL 2 IS 3 BP 249 EP 260 PG 12 WC Oncology; Public, Environmental & Occupational Health SC Oncology; Public, Environmental & Occupational Health GA LB421 UT WOS:A1993LB42100012 PM 8318878 ER PT J AU LEHMAN, TA MODALI, R BOUKAMP, P STANEK, J BENNETT, WP WELSH, JA METCALF, RA STAMPFER, MR FUSENIG, N ROGAN, EM HARRIS, CC AF LEHMAN, TA MODALI, R BOUKAMP, P STANEK, J BENNETT, WP WELSH, JA METCALF, RA STAMPFER, MR FUSENIG, N ROGAN, EM HARRIS, CC TI P53 MUTATIONS IN HUMAN IMMORTALIZED EPITHELIAL-CELL LINES SO CARCINOGENESIS LA English DT Article ID HUMAN PAPILLOMAVIRUS TYPE-16; TUMOR SUPPRESSOR GENE; WILD-TYPE P53; T-ANTIGEN; TRANSFORMED-CELLS; SV40-TRANSFORMED CELLS; RAS ONCOGENE; SV40; CARCINOMA; DNA AB Although rodent celts have been immortalized following transfection with a mutant p53 gene, the role of p53 in the immortalization of human cells is unknown. Therefore, human epithelial cell tines were examined for p53 mutations in exons 4-9 which include the evolutionarily conserved regions. A spontaneously immortalized skin keratinocyte cell line, HaCat, and three ras-transfected clones, have a p53 mutational spectrum that is typical of ultraviolet light induced mutations. A normal finite lifespan cell strain (184) and two benzo[a]pyrene immortalized mammary epithelial cell lines derived from 184 (184A1 and 184B5) contain wild type p53 sequences in exons 4-9, although elevated levels of nuclear p53 indicate an alteration in the stability of the normally transient protein. Wild type p53 was found in human bronchial, esophageal and hepatic epithelial cells immortalized by SV40 T antigen gene and human renal epithelial cells immortalized by adenovirus 5. BEAS-2B, an SV40 T antigen immortalized bronchial epithelial cell line and two subclones, have a germline polymorphism at codon 47. Inactivation of p53 by mechanisms such as mutation or complexing with proteins of DNA tumor viruses appears to be important in the immortalization of human epithelial celts. C1 LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. GERMAN CANC RES CTR, W-6900 HEIDELBERG 1, GERMANY. NCI, HUMAN CARCINOGENESIS LAB, BETHESDA, MD 20892 USA. CHILDRENS MED RES INST, WESTMEAD, NSW, AUSTRALIA. RP LEHMAN, TA (reprint author), BIOSERVE BIOTECHNOL LTD, LAUREL, MD 20707 USA. FU NCI NIH HHS [CA24844] NR 79 TC 318 Z9 320 U1 2 U2 14 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0143-3334 J9 CARCINOGENESIS JI Carcinogenesis PD MAY PY 1993 VL 14 IS 5 BP 833 EP 839 DI 10.1093/carcin/14.5.833 PG 7 WC Oncology SC Oncology GA LD408 UT WOS:A1993LD40800008 PM 8504475 ER PT J AU PERERA, FP TANG, DL ONEILL, JP BIGBEE, WL ALBERTINI, RJ SANTELLA, R OTTMAN, R TSAI, WY DICKEY, C MOONEY, LA SAVELA, K HEMMINKI, K AF PERERA, FP TANG, DL ONEILL, JP BIGBEE, WL ALBERTINI, RJ SANTELLA, R OTTMAN, R TSAI, WY DICKEY, C MOONEY, LA SAVELA, K HEMMINKI, K TI HPRT AND GLYCOPHORIN-A MUTATIONS IN FOUNDRY WORKERS - RELATIONSHIP TO PAH EXPOSURE AND TO PAH DNA ADDUCTS SO CARCINOGENESIS LA English DT Article ID WHITE BLOOD-CELLS; HUMAN LYMPHOCYTES-T; SOMATIC MUTATIONS; ASSAY; QUANTITATION; ANTIBODIES; FREQUENCY; LOCUS AB Mutations were evaluated in workers in an iron foundry with exposure to polycyclic aromatic hydrocarbons (PAHs), measured by personal and area monitoring, ranging from < 5 to 60 ng/m3 of benzo[a]pyrene (B[a]P). Mutation at the hypoxanthine guanine phosphoribosyl transferase (HPRT) and glycophorin A (GPA) loci (measures of molecular effect in lymphocytes and erythrocytes respectively) were assessed to demonstrate their relationship to external exposure at lower levels than previously analyzed in foundry workers at this plant (< 50-200 ng/m3). The relationship between mutations and PAH-DNA adducts measured by immunoassay (as a measure of the biologically effective dose) was also investigated. The markers were analyzed for dose-response and interindividual variability. Workers were classified into three exposure categories (low, medium and high). PAH-DNA adduct values for the low, medium and high exposure groups were 5.19, 6.10 and 9.57 x 10(-8) nucleotides respectively (r = 0.28; P = 0.08). HPRT mutant frequencies (adjusted for age and cloning efficiency) for the low, medium and high exposure groups were 1.04, 1.13 and 1.82 x 10(6)cells respectively and demonstrated an upward trend with increasing exposure that was of borderline significance (r = 0.46, P = 0.06). In contrast, HPRT mutations were highly correlated with PAH-DNA adducts (r = 0.67; P = 0.004). Interindividual variability in mutant frequencies ranged from 1.5- to 4.5-fold within the three exposure categories. With respect to GPA variants, NN frequency (Vf) in erythrocytes (which reflects chromosomal loss and duplication, recombination or gene conversion) was not positively correlated with PAH exposure. The level of NO Vf (arising from small-scale structural mutations in the GPA gene or from larger-scale chromosomal rearrangements or deletions) increased slightly, but not significantly, over the three exposure groups from 8.2 to 10.7 to 11.8/10(6) cells (P = 0.32). Interindividual variation in GPA NN Vf ranged from 2- to 18-fold and in GPA NO from 4- to 5-fold. NN and NO Vf were highly correlated (P = 0.001) but no correlation was seen between GPA and HPRT or between GPA and PAH-DNA adducts. Thus, the most interesting and novel finding is that, even at relatively low exposures to PAH, HPRT mutations were increased in parallel with PAH-DNA adducts. The observed association between PAH-DNA adducts and HPRT gene mutation in humans is consistent with experimental data for PAHs. These results support the use of both biomonitoring and personal ambient monitoring in further molecular epidemiology studies. C1 UNIV VERMONT,CTR CANC,GENET LAB,BURLINGTON,VT 05401. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. KAROLINSKA INST,CNT,S-14152 HUDDINGE,SWEDEN. INST OCCUPAT HLTH,SF-00290 HELSINKI 29,FINLAND. RP PERERA, FP (reprint author), COLUMBIA UNIV,60 HAVEN AVE,B109,NEW YORK,NY 10032, USA. RI Ottman, Ruth/O-2371-2013; OI Mooney, LaVerne A./0000-0003-1120-356X FU NCEH CDC HHS [NIEHS 1-P01-E505249] NR 23 TC 60 Z9 60 U1 0 U2 0 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0143-3334 J9 CARCINOGENESIS JI Carcinogenesis PD MAY PY 1993 VL 14 IS 5 BP 969 EP 973 DI 10.1093/carcin/14.5.969 PG 5 WC Oncology SC Oncology GA LD408 UT WOS:A1993LD40800030 PM 8504491 ER PT J AU ALLAN, ML AF ALLAN, ML TI TOUGHNESS OF REINFORCEMENT CONCRETE BOND IN TENSILE LOADING SO CEMENT AND CONCRETE RESEARCH LA English DT Article AB Corrosion of reinforcement results in tensile loading of the bond between reinforcement and concrete. Double cantilever beam tests were performed to measure the toughness of the reinforcement bar/concrete interface in tensile loading. The sample mean toughness was determined to be 0.115 N/mm. The bar/concrete toughness has a similar magnitude to reported values of bulk concrete toughness. Hence, the fracture properties of the interface and the bulk concrete are equally important in the optimization of reinforced concrete durability. RP ALLAN, ML (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,DIV ENERGY EFFICIENCY & CONSERVAT,UPTON,NY 11973, USA. RI Berndt, Marita/D-1901-2014 OI Berndt, Marita/0000-0002-6622-0597 NR 11 TC 0 Z9 0 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0008-8846 J9 CEMENT CONCRETE RES JI Cem. Concr. Res. PD MAY PY 1993 VL 23 IS 3 BP 609 EP 617 DI 10.1016/0008-8846(93)90012-X PG 9 WC Construction & Building Technology; Materials Science, Multidisciplinary SC Construction & Building Technology; Materials Science GA KY524 UT WOS:A1993KY52400012 ER PT J AU ROGAN, EG DEVANESAN, PD RAMAKRISHNA, NVS HIGGINBOTHAM, S PADMAVATHI, NS CHAPMAN, K CAVALIERI, EL JEONG, H JANKOWIAK, R SMALL, GJ AF ROGAN, EG DEVANESAN, PD RAMAKRISHNA, NVS HIGGINBOTHAM, S PADMAVATHI, NS CHAPMAN, K CAVALIERI, EL JEONG, H JANKOWIAK, R SMALL, GJ TI IDENTIFICATION AND QUANTITATION OF BENZO[A]PYRENE DNA ADDUCTS FORMED IN MOUSE SKIN SO CHEMICAL RESEARCH IN TOXICOLOGY LA English DT Article ID CARCINOGENESIS; BENZO(A)PYRENE; CHEMICALS; INVITRO; INVIVO AB The DNA adducts of benzo[a]pyrene (BP) formed in vitro were previously identified and quantitated. In this paper, we report the identification and quantitation of the depurination adducts of BP, 8-(benzo[a]pyren-6-yl)guanine (BP-6-C8Gua), BP-6-N7Gua, and BP-6-N7Ade, formed in mouse skin by one-electron oxidation, as well as the major stable adduct formed via the diolepoxide pathway, BP diolepoxide bound at C-10 to the 2-amino of dG (BPDE-10-N2dG). Identification of the depurination adducts was achieved by HPLC and fluorescence line narrowing spectroscopy. The depurination adducts, BP-6-C8Gua (34%), BP-6-N7Gua (10%), and BP-6-N7Ade (30%), constituted 74% of the adducts found in mouse skin 4 h after treatment with BP. The stable adduct BPDE-10-N2dG accounted for 22 % of the adducts. Treatment of the skin with BP-7,8-dihydrodiol or BP diolepoxide yielded almost exclusively the stable adduct BPDE-10-N2dG. When BP or BP-7,8-dihydrodiol was bound to RNA or denatured DNA in reactions catalyzed by rat liver microsomes, no depurination adducts were detected. The profiles of stable adducts were similar both qualitatively and quantitatively with native or denatured DNA. With activation of BP by horseradish peroxidase, the profiles of stable adducts differed with native and denatured DNA. The total amount of adducts with denatured DNA was only 25% of the amount detected with native DNA. No depurination adducts were detected with denatured DNA or RNA in the peroxidase system. The results reported here demonstrate that in mouse skin BP-DNA adducts are predominantly formed by one-electron oxidation and that this mechanism of activation requires double helical DNA for formation of adducts. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. RP ROGAN, EG (reprint author), UNIV NEBRASKA,MED CTR,EPPLEY INST RES CANC & ALLIED DIS,600 S 42ND ST,OMAHA,NE 68198, USA. FU NCI NIH HHS [R01-CA44686, R01-CA25176, P01-CA49210] NR 24 TC 115 Z9 118 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0893-228X J9 CHEM RES TOXICOL JI Chem. Res. Toxicol. PD MAY-JUN PY 1993 VL 6 IS 3 BP 356 EP 363 DI 10.1021/tx00033a017 PG 8 WC Chemistry, Medicinal; Chemistry, Multidisciplinary; Toxicology SC Pharmacology & Pharmacy; Chemistry; Toxicology GA LD004 UT WOS:A1993LD00400017 PM 7686408 ER PT J AU DEVANESAN, PD RAMAKRISHNA, NVS PADMAVATHI, NS HIGGINBOTHAM, S ROGAN, EG CAVALIERI, EL MARSCH, GA JANKOWIAK, R SMALL, GJ AF DEVANESAN, PD RAMAKRISHNA, NVS PADMAVATHI, NS HIGGINBOTHAM, S ROGAN, EG CAVALIERI, EL MARSCH, GA JANKOWIAK, R SMALL, GJ TI IDENTIFICATION AND QUANTITATION OF 7,12-DIMETHYLBENZ[A]ANTHRACENE-DNA ADDUCTS FORMED IN MOUSE SKIN SO CHEMICAL RESEARCH IN TOXICOLOGY LA English DT Article ID DNA ADDUCTS; AROMATIC-HYDROCARBONS; METABOLIC-ACTIVATION; CARCINOGENS; INVITRO; INVIVO AB Identification and quantitation of the depurination and stable DNA adducts of 7,12-dimethylbenz[a]anthracene (DMBA) formed by cytochrome P450 in rat liver microsomes previously established one-electron oxidation as the predominant mechanism of activation of DMBA to bind to DNA. In this paper we report the identification and quantitation of the depurination and stable DMBA-DNA adducts formed in mouse skin. The depurination adducts, which constitute 99 % of all the adducts detected, are DMBA bound at the 12-methyl group to the N-7 of adenine or guanine, namely, 7-methylbenz [a] anthracene (MBA)- 12-CH2-N7Ade and 7-MBA-12-CH2-N7Gua. The depurination adducts were identified by HPLC and fluorescence line narrowing spectroscopy. The stable DNA adducts were analyzed by the P-32-postlabeling method. Almost 4 times as much of the depurination adduct 7-MBA-12-CH2-N7 Ade (79%) was formed compared to 7-MBA-12-CH2-N7Gua (20 %). The stable adducts accounted for only 1 % of all the adducts detected and 80 % of these were formed from DMBA diolepoxide. The binding of DMBA to DNA specifically at the 12-CH3 group is consistent with the results of carcinogenicity experiments in which this group plays a key role. When DMBA was bound to RNA or denatured DNA in reactions catalyzed by microsomes or by horseradish peroxidase (HRP), no depurination DNA adducts of DMBA were detected. The amount of stable DNA adducts observed with denatured DNA was 70 % lower in the HRP system and 30 % lower in the microsomal system compared to native DNA. In the microsomal system, just the two major adduct spots decreased, whereas the amounts of all of the adducts decreased with HRP. These results demonstrate that in mouse skin, DMBA-DNA adducts are predominantly formed via one-electron oxidation and that the adducts formed by the diolepoxide pathway are minor. The double helical structure of DNA is necessary for formation of adducts by one-electron oxidation but is not a critical factor in the diolepoxide pathway. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT MED,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. RP CAVALIERI, EL (reprint author), UNIV NEBRASKA,MED CTR,EPPLEY INST RES CANC & ALLIED DIS,600 S 42ND ST,OMAHA,NE 68198, USA. FU NCI NIH HHS [P01-CA49210, R01-CA25176, R01-CA44686] NR 28 TC 68 Z9 70 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0893-228X J9 CHEM RES TOXICOL JI Chem. Res. Toxicol. PD MAY-JUN PY 1993 VL 6 IS 3 BP 364 EP 371 DI 10.1021/tx00033a018 PG 8 WC Chemistry, Medicinal; Chemistry, Multidisciplinary; Toxicology SC Pharmacology & Pharmacy; Chemistry; Toxicology GA LD004 UT WOS:A1993LD00400018 PM 7686409 ER PT J AU WOO, LK AF WOO, LK TI INTERMETAL OXYGEN, SULFUR, SELENIUM, AND NITROGEN ATOM TRANSFER-REACTIONS SO CHEMICAL REVIEWS LA English DT Review ID ELECTRON-TRANSFER REACTIONS; FERRYL FEO2+ COMPLEXES; RHENIUM-OXO COMPOUNDS; METAL-COMPLEXES; MANGANESE PORPHYRINS; SELF-EXCHANGE; STRUCTURAL CHARACTERIZATION; CHROMIUM(III) PORPHYRINS; TEMPERATURE DEPENDENCES; TITANIUM(IV) PORPHYRINS C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP WOO, LK (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 185 TC 114 Z9 114 U1 0 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0009-2665 J9 CHEM REV JI Chem. Rev. PD MAY PY 1993 VL 93 IS 3 BP 1125 EP 1136 DI 10.1021/cr00019a012 PG 12 WC Chemistry, Multidisciplinary SC Chemistry GA LB960 UT WOS:A1993LB96000013 ER PT J AU MARKING, GA FRANZEN, HF AF MARKING, GA FRANZEN, HF TI ZR6.45NB4.55P4, A NEW MIXED-TRANSITION-METAL PHOSPHIDE STRUCTURE SO CHEMISTRY OF MATERIALS LA English DT Article ID CRYSTAL-STRUCTURE; SYSTEM AB A new structure which is similar to that of many known binary early-transition-metal phosphides, sulfides, and selenides has been found in the ternary Zr-Nb-P system. The compound Zr6.45Nb4.55P4 was synthesized using high-temperature techniques and characterized through X-ray single-crystal experiments. The space group is Immm with lattice parameters a = 15.917 (1) angstrom, b = 9.5684 (9) angstrom, and c = 3.5892 (3) angstrom. Bond order calculations revealed the approximate metal site occupancies and anomalous scattering allowed refinement of the metal site occupancies. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. NR 21 TC 21 Z9 21 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD MAY PY 1993 VL 5 IS 5 BP 678 EP 680 DI 10.1021/cm00029a017 PG 3 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA LC738 UT WOS:A1993LC73800017 ER PT J AU SCHLUETER, JA WANG, HH LATHROP, MW GEISER, U CARLSON, KD DUDEK, JD YACONI, GA WILLIAMS, JM AF SCHLUETER, JA WANG, HH LATHROP, MW GEISER, U CARLSON, KD DUDEK, JD YACONI, GA WILLIAMS, JM TI ESR STUDY OF THE FORMATION OF SUPERCONDUCTING RB3C60 FROM SOLUTION SO CHEMISTRY OF MATERIALS LA English DT Article ID ELECTRON-SPIN-RESONANCE; M3C60 SUPERCONDUCTORS; C70 FULLERENES; C60; K3C60; SPECTRA; ANION AB A solution-based procedure, requiring reaction times less than 2 h, has been developed for the rapid preparation of Rb3C60 (T(c) onset = 29.0 +/- 0.1 K) with superconducting shielding fractions near 50 %. A 9:1 (vol) toluene/benzonitrile solvent system was used, which prevents premature precipitation of C60 as a monoanion. The RbxC60 material prepared in this manner from solution has been characterized by an ESR line-shape analysis at room temperature. In rigorously dried toluene, the primary product is RbC60, but as the solvent polarity is increased with the addition of benzonitrile as a ''redox catalyst'', a greater fraction of superconducting Rb3C60 is precipitated. The different room-temperature ESR line widths and integrated spin susceptibilities of these two products are used to quantify the relative yields of these two C60n-species. The superconducting shielding fraction of the as formed ''RbxC60'' product is found to correlate linearly with the Rb3C60 content obtained from ESR line-shape analysis, confirming that Rb3C60 is the only superconducting component prepared via this solution phase technique. ESR analysis revealed that Rb3C60 samples (with shielding fractions near 100%) prepared by the conventional vapor phase technique contained a few percent RbC60. X-ray powder diffraction confirmed the presence of trace amounts of RbCN in the solution-phase prepared materials. C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. NR 40 TC 18 Z9 19 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD MAY PY 1993 VL 5 IS 5 BP 720 EP 725 DI 10.1021/cm00029a025 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA LC738 UT WOS:A1993LC73800025 ER PT J AU GREBMEIER, JM AF GREBMEIER, JM TI STUDIES OF PELAGIC BENTHIC COUPLING EXTENDED ONTO THE SOVIET CONTINENTAL-SHELF IN THE NORTHERN BERING AND CHUKCHI SEAS SO CONTINENTAL SHELF RESEARCH LA English DT Article ID DEEP OCEAN; SEDIMENT; MARINE; PB-210; MATTER; FLUX; FLOW AB Studies of pelagic-benthic coupling and benthic carbon cycling in the northern Bering and Chukchi seas were extended onto the Soviet continental shelf as part of the third U.S.A.-U.S.S.R. Oceanographic Expedition to the Bering and Chukchi seas in 1988. High sediment oxygen uptake rates (an indicator of food supply to the benthos) and benthic biomass were observed in the western shelf regions of the Gulf of Anadyr, Chirikov Basin and southern Chukchi Sea. Low sediment respiration and faunal biomass were observed in the central and slope areas of the Gulf of Anadyr and near the Alaska coastline. Both high sediment respiration and benthic biomass were related to regions of high carbon deposition to the benthos and sediment organic carbon content. Preliminary studies of sediment accumulation, measured using organic carbon content and atmospherically-derived Pb-210 loop values in surface sediments, were low in the sandy regions of the northern Bering Sea, with higher sediment accumulation zones occurring in the silt and clay regions in the central Gulf of Anadyr and southern Chukchi Sea. Hydrodynamics have a major influence on organic carbon loading and sediment composition, which in turn influences benthic community structure, biomass and sediment respiration in this Arctic region. C1 OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. RP GREBMEIER, JM (reprint author), UNIV TENNESSEE,GRAD PROGRAM ECOL,KNOXVILLE,TN 37996, USA. RI Grebmeier, Jacqueline/L-9805-2013 OI Grebmeier, Jacqueline/0000-0001-7624-3568 NR 39 TC 66 Z9 69 U1 2 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD MAY-JUN PY 1993 VL 13 IS 5-6 BP 653 EP 668 DI 10.1016/0278-4343(93)90098-I PG 16 WC Oceanography SC Oceanography GA LA351 UT WOS:A1993LA35100008 ER PT J AU ADLER, TA WALTERS, RP AF ADLER, TA WALTERS, RP TI REPASSIVATION OF 304-STAINLESS STEEL INVESTIGATED WITH A SINGLE SCRATCH TEST SO CORROSION LA English DT Article DE 304-STAINLESS STEEL; CURRENT TRANSIENT; DECONVOLUTION; REPASSIVATION; SCRATCH TEST ID GENERATED TITANIUM SURFACES; 304L STAINLESS-STEEL; ABRASIVE WEAR; STRESS-CORROSION; FILM GROWTH; KINETICS; ELECTROCHEMISTRY; DEPASSIVATION; ELECTRODES; CRACKING AB Reformation of the passive film on 304 stainless steel (UNS S 30400) was investigated with a scratch test. Regrowth of the passive film was measured by recording the current that resulted from forming the scratch. Charge consumed during the reformation of the film was compared to wear produced by the scratch. The current density from an incremental area of the scratch was extracted from the measured current transients using the width of the scratch as a function of time. The maximum current density and the charge density were dependent linearly on the area fraction of bare surface. Other parameters used in the model of current transients did not change as the area fraction of bare surface changed. Results showed the passive film remained adherent to the surface of the stainless steel during the rubbing mode of wear. RP ADLER, TA (reprint author), US BUR MINES,ALBANY RES CTR,1450 QUEEN AVE SW,ALBANY,OR 97321, USA. NR 32 TC 19 Z9 19 U1 0 U2 1 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 SN 0010-9312 J9 CORROSION JI Corrosion PD MAY PY 1993 VL 49 IS 5 BP 399 EP 408 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA LE110 UT WOS:A1993LE11000007 ER PT J AU ESPOSITO, MS BRUSCHI, CV AF ESPOSITO, MS BRUSCHI, CV TI DIPLOID YEAST-CELLS YIELD HOMOZYGOUS SPONTANEOUS MUTATIONS SO CURRENT GENETICS LA English DT Article DE SACCHAROMYCES-CEREVISIAE; MUTATIONAL HOMOZYGOSIS; LOSS OF HETEROZYGOSITY; MUTATION; RECOMBINATION ID SPONTANEOUS MITOTIC RECOMBINATION; SACCHAROMYCES; STAGE AB A leucine-requiring hybrid of Saccharomyces cerevisiae, homoallelic at the LEU1 locus (leu1-12/leu1-12) and heterozygous for three chromosome-VII genetic markers distal to the LEU1 locus, was employed to inquire: (1) whether spontaneous gene mutation and mitotic segregation of heterozygous markers occur in positive nonrandom association and (2) whether homozygous LEU1/LEU1 mutant diploids are generated. The results demonstrate that gene mutation of leu1-12 to LEU1 and mitotic segregation of heterozygous chromosome-VII markers occur in strong positive nonrandom association, suggesting that the stimulatory DNA lesion is both mutagenic and recombinogenic. In addition, genetic analysis of diploid Leu+ revertants revealed that approximately 3% of mutations of leu1-12 to LEU1 result in LEU1/LEU1 homozygotes. Red-white sectored Leu+ colonies exhibit genotypes that implicate post-replicational chromatid breakage and exchange near the site of leu1-12 reversion, chromosome loss, and subsequent restitution of diploidy, in the sequence of events leading to mutational homozygosis. By analogy, diploid cell populations can yield variants homozygous for novel recessive gene mutations at biologically significant rates. Mutational homozygosis may be relevant to both carcinogenesis and the evolution of asexual diploid organisms. C1 UN,IND DEV ORG,INT CTR GENET ENGN & BIOTECHNOL,DEPT MICROBIOL,I-34012 TRIESTE,ITALY. RP ESPOSITO, MS (reprint author), LAWRENCE BERKELEY LAB,DIV LIFE SCI,BERKELEY,CA 94720, USA. NR 14 TC 32 Z9 32 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0172-8083 J9 CURR GENET JI Curr. Genet. PD MAY-JUN PY 1993 VL 23 IS 5-6 BP 430 EP 434 DI 10.1007/BF00312630 PG 5 WC Genetics & Heredity SC Genetics & Heredity GA LY916 UT WOS:A1993LY91600010 PM 8319299 ER PT J AU FORD, VA KENNEL, SJ AF FORD, VA KENNEL, SJ TI AN INTRACISTERNAL A-PARTICLE DNA-SEQUENCE IS CLOSELY LINKED TO THE THROMBOMODULIN GENE IN SOME STRAINS OF LABORATORY MICE SO DNA AND CELL BIOLOGY LA English DT Article ID EARLY MOUSE EMBRYOS; MESSENGER-RNA; NATURAL ANTICOAGULANT; FETAL DEVELOPMENT; HEMANGIOMA CELLS; FETOMODULIN; IDENTIFICATION; EXPRESSION; INSERTION; PROTEIN AB Sequence analysis of the 5' end of the thrombomodulin (TM) gene has identified a difference in two strains of laboratory mice, BALB/cBD (maintained at the Oak Ridge National Laboratory) and the strain used for the sequence listed in the GenBank data base. An intracisternal A-particle (IAP) provirus was present in the BALB/cBD sequence but absent from the GenBank sequence. Thus, there are two different 5' regions for the TM gene in mice. Southern blot and polymerase chain reaction analyses on other mouse strains demonstrated the presence of this proviral sequence in five out of ten strains tested. Northern blot analyses demonstrated that there were differences (up to three-fold) in the steady-state levels of TM mRNA among the strains. However, TM mRNA levels did not correlate directly with the presence of the IAP DNA upstream from the TM gene. This is in contrast to other loci (the interleukin-3 gene, c-mos, and the immunoglobulin Ck gene), in which the IAP element is known to affect levels of RNA transcription. While the IAP provirus does not appear to have an effect on TM transcription under normal conditions, it is possible that transcription levels altered by factors like thrombin and tumor necrosis factor are affected by the IAP provirus. C1 OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37830. UNIV TENNESSEE,OAK RIDGE GRAD SCH BIOMED SCI,OAK RIDGE,TN 37830. NR 37 TC 7 Z9 7 U1 0 U2 0 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 SN 1044-5498 J9 DNA CELL BIOL JI DNA Cell Biol. PD MAY PY 1993 VL 12 IS 4 BP 311 EP 318 DI 10.1089/dna.1993.12.311 PG 8 WC Biochemistry & Molecular Biology; Cell Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Cell Biology; Genetics & Heredity GA LC164 UT WOS:A1993LC16400004 PM 8388220 ER PT J AU ORTH, CJ ATTREP, M QUINTANA, LR ELDER, WP KAUFFMAN, EG DINER, R VILLAMIL, T AF ORTH, CJ ATTREP, M QUINTANA, LR ELDER, WP KAUFFMAN, EG DINER, R VILLAMIL, T TI ELEMENTAL ABUNDANCE ANOMALIES IN THE LATE CENOMANIAN EXTINCTION INTERVAL - A SEARCH FOR THE SOURCE(S) SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article ID WESTERN INTERIOR; MASS EXTINCTIONS; UNITED-STATES; TURONIAN STAGE; COMET SHOWERS; BOUNDARY; PATTERNS; IMPACTS; BASIN; EVENT AB Elemental abundances have been measured by neutron activation methods across the Cenomanian-Turonian (late Cretaceous) extinction interval in samples collected from sixteen sites in the Western Interior Basin of North America and from twelve widely separated locations around the globe, including six ODP/DSDP sites. In most Western Interior Basin sites, in Colombia, and in western Europe (weaker), two closely spaced elemental abundance peaks occur in the upper Cenomanian (approximately 92 m.y.), spanning the ammonite zones of Sciponoceras gracile through Neocardioceras juddii. Elements with anomalously high concentrations include Sc, Ti, V, Cr, Mn, Co, Ni, Ir, Pt and Au. The lower peak coincides with the disappearance (extinction) of the foraminifer Rotalipora cushmani. In North American sections R. greenhornensis also disappears at or just below this horizon, but in Europe it disappears considerably earlier than R. cushmani. A series of molluscan extinction and speciation or migration events also begins near the stratigraphic level of the lower elemental abundance peak. The well-documented positive delta C-13 excursion begins just before the extinctions and the elemental anomalies, and continues into the lower Turonian, well above the upper anomaly. This carbon isotope excursion has been observed in East European sections where we find little or no evidence of the elemental anomalies, suggesting that the two phenomena may not be tightly coupled. Elemental abundance ratios in the anomalies closely resemble those of Mid-Atlantic Ridge basalt or Hawaiian lava (tholeiitic), but not those of Cl chondrite, black shale, average crustal rocks, or lamproite and kimberlite of roughly similar age in southeastern Kansas. The excess Ir and other siderophiles hint at possible large-body impact(s) for the source. However, we have not located microspherules (other than biogenic calcispheres) or shocked mineral grains in any of our samples. Furthermore, Sc, Ti, V and Mn are not enriched in differentiated Solar-System bodies. Although the weak geochemical signal from comet impact(s) could be masked by the strong terrestrial-like overprint, these anomalies more likely resulted either from intense seafloor spreading activity or merely from increased circulation of deep, metal-rich water associated with the large late Cenomanian through early Turonian eustatic rise, and deep-water opening of the South Atlantic. The flooding of continental seaways and margins also could have contributed to the anomalies by preventing much continental detritus from diluting the normal background marine geochemical component. C1 UNIV COLORADO,DEPT GEOL SCI,BOULDER,CO 80309. US GEOL SURVEY,MENLO PK,CA 94025. RP ORTH, CJ (reprint author), LOS ALAMOS NATL LAB,DIV ISOTOPE & NUCL CHEM,LOS ALAMOS,NM 87545, USA. NR 51 TC 52 Z9 54 U1 0 U2 9 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 MAY PY 1993 VL 117 IS 1-2 BP 189 EP 204 DI 10.1016/0012-821X(93)90126-T PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA LH368 UT WOS:A1993LH36800014 ER PT J AU FARRAR, CR BAKER, WE AF FARRAR, CR BAKER, WE TI EXPERIMENTAL ASSESSMENT OF LOW-ASPECT-RATIO, REINFORCED-CONCRETE SHEAR WALL STIFFNESS SO EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS LA English DT Article AB Low-aspect-ratio, reinforced concrete shear walls are the primary lateral-load-carrying element in many structures designed for protective purposes. A review of the technical literature shows that considerable uncertainty exists regarding the elastic stiffness these structures will exhibit during seismic excitation. Because of this uncertainty, current design practice often employs a stiffness reduction factor. In an attempt to develop accurate information regarding the stiffness of these structures, 13 shear wall elements were tested statically; dynamically, with simulated seismic base excitations on a shake table; and with experimental modal analysis procedures. Results of these tests show that the shear wall's stiffness can be accurately estimated with a mechanics-of-materials analysis that accounts for shear deformation. RP FARRAR, CR (reprint author), LOS ALAMOS NATL LAB,MSJ576,LOS ALAMOS,NM 87545, USA. NR 44 TC 2 Z9 2 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0098-8847 J9 EARTHQUAKE ENG STRUC JI Earthq. Eng. Struct. Dyn. PD MAY PY 1993 VL 22 IS 5 BP 373 EP 387 DI 10.1002/eqe.4290220502 PG 15 WC Engineering, Civil; Engineering, Geological SC Engineering GA LB564 UT WOS:A1993LB56400001 ER PT J AU GIORDANO, N PASSALACQUA, E ANTONUCCI, PL PINO, L VIVALDI, M PATTI, A KINOSHITA, K AF GIORDANO, N PASSALACQUA, E ANTONUCCI, PL PINO, L VIVALDI, M PATTI, A KINOSHITA, K TI INFLUENCE OF PHYSICOCHEMICAL PROPERTIES ON THE PERFORMANCE OF PT/C POROUS-ELECTRODES FOR OXYGEN REDUCTION IN PHOSPHORIC-ACID SO ELECTROCHIMICA ACTA LA English DT Article DE PHOSPHORIC ACID FUEL CELLS; OXYGEN REDUCTION; OXYGEN GAIN; TAFEL SLOPE; ACTIVITY DECAY ID PLATINUM CRYSTALLITE SIZE; GAS-DIFFUSION ELECTRODE; ELECTROCHEMICAL REDUCTION; CATALYST LAYER; PARTICLE-SIZE; CARBON; TEMPERATURE AB Oxygen reduction on Pt supported on carbon black in PTFE-bonded porous electrodes in 98% H3PO4 at 170-degrees-C was investigated. The influence of the Pt surface area and the volume of H3PO4 in the electrode structure (per cent acid occupation, PAO) on the performance of porous electrodes (ie current-potential behavior, potential at a constant current density of 200 mA cm-2, oxygen gain) were evaluated. The results clearly show that the Pt surface area has a major influence on the Tafel slope, electrode polarization, electrode potential decay at constant current density, and oxygen gain. On the other hand, these parameters do not show a clear trend with PAO. C1 UNIV REGGIO CALABRIA,FAC ENGN,I-89100 REGGIO CALABRIA,ITALY. LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,BERKELEY,CA 94720. RP GIORDANO, N (reprint author), CNR,INST TRANSFORMAT & STORAGE ENERGY,VIA SALITA S LUCIA CONTESSE 39,I-98126 ST LUCIA,ITALY. OI Pino, Lidia/0000-0002-3298-9197; PASSALACQUA, ENZA/0000-0002-9094-4333 NR 25 TC 9 Z9 10 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD MAY PY 1993 VL 38 IS 7 BP 913 EP 918 DI 10.1016/0013-4686(93)87009-3 PG 6 WC Electrochemistry SC Electrochemistry GA KW618 UT WOS:A1993KW61800008 ER PT J AU MOSHER, JC SPENCER, ME LEAHY, RM LEWIS, PS AF MOSHER, JC SPENCER, ME LEAHY, RM LEWIS, PS TI ERROR-BOUNDS FOR EEG AND MEG DIPOLE SOURCE LOCALIZATION SO ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY LA English DT Article DE SPATIOTEMPORAL SOURCE MODELING; EEG; MEG; DIPOLE SOURCE LOCALIZATION ERROR; DIPOLE MOMENT ERROR ID MAGNETOENCEPHALOGRAM; ELECTROENCEPHALOGRAM; POTENTIALS; MODELS; FIELDS; HEAD AB General formulas are presented for computing a lower bound on localization and moment error for electroencephalographic (EEG) or magnetoencephalographic (MEG) current source dipole models with arbitrary sensor array geometry. Specific EEG and MEG formulas are presented for multiple dipoles in a head model with 4 spherical shells. Localization error bounds are presented for both EEG and MEG for several different sensor configurations. Graphical error contours are presented for 127 sensors covering the upper hemisphere, for both 37 sensors and 127 sensors covering a smaller region, and for the standard 10-20 EEG sensor arrangement. Both 1- and 2-dipole cases were examined for all possible dipole orientations and locations within a head quadrant. The results show a strong dependence on absolute dipole location and orientation. The results also show that fusion of the EEG and MEG measurements into a combined model reduces the lower bound. A Monte Carlo simulation was performed to check the tightness of the bounds for a selected case. The simple head model, the low power noise and the few strong dipoles were all selected in this study as optimistic conditions to establish possibly fundamental resolution limits for any localization effort. Results, under these favorable assumptions, show comparable resolutions between the EEG and the MEG models, but accuracy for a single dipole, in either case, appears limited to several millimeters for a single time slice. The lower bounds increase markedly with just 2 dipoles. Observations are given to support the need for full spatiotemporal modeling to improve these lower bounds. All of the simulation results presented can easily be scaled to other instances of noise power and dipole intensity. C1 UNIV SO CALIF,INST SIGNAL & IMAGE PROC,LOS ANGELES,CA 90089. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. TRW CO INC,REDONDO BEACH,CA 90278. NR 32 TC 142 Z9 142 U1 0 U2 3 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0013-4694 J9 ELECTROEN CLIN NEURO JI Electroencephalogr. Clin. Neurophysiol. PD MAY PY 1993 VL 86 IS 5 BP 303 EP 321 DI 10.1016/0013-4694(93)90043-U PG 19 WC Engineering, Biomedical; Clinical Neurology SC Engineering; Neurosciences & Neurology GA LD488 UT WOS:A1993LD48800001 PM 7685264 ER PT J AU LEE, TT LILLARD, SJ YEUNG, ES AF LEE, TT LILLARD, SJ YEUNG, ES TI SCREENING AND CHARACTERIZATION OF BIOPHARMACEUTICALS BY HIGH-PERFORMANCE CAPILLARY ELECTROPHORESIS WITH LASER-INDUCED NATIVE FLUORESCENCE DETECTION SO ELECTROPHORESIS LA English DT Article; Proceedings Paper CT 5TH INTERNATIONAL SYMP ON HIGH PERFORMANCE CAPILLARY ELECTROPHORESIS CY JAN, 1993 CL ORLANDO, FL ID THROMBIN-CATALYZED ACTIVATION; DNA-DERIVED PROTEINS; ZONE ELECTROPHORESIS; FACTOR-XIII; GROWTH-HORMONE; PURIFICATION AB High-performance capillary electrophoresis (HPCE) with laser-induced native fluorescence (LIF) detection is used to address significant problems in the quality control of biopharmaceuticals. All of the biopharmaceuticals studied can be detected at subnanomolar levels with linear dynamic ranges of at least 3 orders of magnitude. HPCE/LIF can determine impurities in ''purified'' biopharmaceuticals present in amounts less than 0.01% (i. e., at 4 X 10(-11) M) that of the major component. With HPCE/LIF, detection sensitivity is thus no longer a concern in the assaying of active ingredients in biopharmaceutical dosage formulations. The peptide mapping of biopharmaceuticals present at 1 X 10(-7) M (or an injected limit of detection of 60 amol) is presented. Also, kinetic information on the reaction of a recombinant enzyme-drug with its substrate present at the micromolar level has been extracted from electropherograms acquired in real-time. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. NR 40 TC 26 Z9 26 U1 0 U2 4 PU VCH PUBLISHERS INC PI DEERFIELD BEACH PA 303 NW 12TH AVE, DEERFIELD BEACH, FL 33442-1788 SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD MAY-JUN PY 1993 VL 14 IS 5-6 BP 429 EP 438 DI 10.1002/elps.1150140168 PG 10 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA LJ421 UT WOS:A1993LJ42100007 PM 8354226 ER PT J AU WAHL, JH GOODLETT, DR UDSETH, HR SMITH, RD AF WAHL, JH GOODLETT, DR UDSETH, HR SMITH, RD TI USE OF SMALL-DIAMETER CAPILLARIES FOR INCREASING PEPTIDE AND PROTEIN-DETECTION SENSITIVITY IN CAPILLARY-ELECTROPHORESIS MASS-SPECTROMETRY SO ELECTROPHORESIS LA English DT Article; Proceedings Paper CT 5TH INTERNATIONAL SYMP ON HIGH PERFORMANCE CAPILLARY ELECTROPHORESIS CY JAN, 1993 CL ORLANDO, FL ID ELECTROSPRAY IONIZATION INTERFACE; LASER-INDUCED FLUORESCENCE; ZONE ELECTROPHORESIS; SEQUENCE INFORMATION; SILICA CAPILLARIES; PERFORMANCE; SEPARATION; ISOTACHOPHORESIS; BUFFERS AB The use of small ID capillaries is shown to provide a substantial increase in sensitivity for capillary electrophoresis-electrospray ionization/mass spectrometry (CE-ESI/MS). In a comparison using capillaries ranging from either 100 to 10 mum or 50 to 5 mum ID and chemically modified with aminopropylsilane, a 25- to 50-fold increase in sensitivity was observed for both peptide and protein mixtures. This enhanced solute sensitivity allowed the detection of approximately 150 attomoles of melittin (2845 Da) with selected ion monitoring and 600 attomoles of carbonic anhydrase (29 157 Da) while scanning forCE-MS with a quadrupole mass spectrometer. For the protein mixture, mass spectra of sufficient quality for precise molecular weight determination (less-than-or-equal-to 0.05 %) were obtained for 600 attomole injections using a 5 mum ID capillary. The increase in sensitivity with small capillary diameters can be primarily attributed to a reduced mass flow rate of buffer and other background constituents into the electrospray source, which allows for greater sample ionization efficiency. A model that qualitatively accounts for the results is presented, but quantitative agreement is precluded due to difficulties in accounting for contributions due to a liquid sheath flow used with the electrospray source. The model accounts for the observation that the ESI/MS appears to function as a concentration-sensitive detector under many conditions using large-diameter capillaries. A transition occurs, however, to a regime where the ESI/MS functions as a mass flow-sensitive detector for small-diameter capillaries, where the ESI current is limited by the rate of delivery to the ESI source of charge carrying species in solution. These results suggest peptide and protein analysis at low attomole and subattomole levels should be obtainable with alternative types of mass spectrometers. C1 PACIFIC NW LAB, DEPT CHEM SCI, CHEM METHODS & SEPARAT GRP, RICHLAND, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 33 TC 89 Z9 89 U1 2 U2 16 PU VCH PUBLISHERS INC PI DEERFIELD BEACH PA 303 NW 12TH AVE, DEERFIELD BEACH, FL 33442-1788 SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD MAY-JUN PY 1993 VL 14 IS 5-6 BP 448 EP 457 DI 10.1002/elps.1150140170 PG 10 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA LJ421 UT WOS:A1993LJ42100009 PM 8354228 ER PT J AU BUCHANAN, AC BRITT, PF THOMAS, KB BIGGS, CA AF BUCHANAN, AC BRITT, PF THOMAS, KB BIGGS, CA TI A SURFACE-IMMOBILIZED MODEL-COMPOUND INVESTIGATION OF CATALYTIC REACTIONS IN DISPERSED SOLIDS SO ENERGY & FUELS LA English DT Article ID COAL-LIQUEFACTION; PHENYL ETHER; THERMOLYSIS; HYDROPYROLYSIS; HYDROGENOLYSIS; REARRANGEMENT; DECOMPOSITION; CHEMISTRY; PATHWAYS AB Reactions of the silica-immobilized model compounds, almost-equal-to Ph(CH2)(n)Ph (n = 1, 3, 4) and almost-equal-to PhCH2CH2OPh, with dispersed acid catalysts have been studied at 310-375-degrees-C in the solid state. Reactions of these model compounds in the presence of a small particle size (15 nm) silica-1% alumina catalyst yield products typically expected for acid-catalyzed cracking of alkylaromatics involving carbocation intermediates. The reactions of these well-defined model systems, including their dependence on the physical and chemical nature of the catalyst, provide compelling evidence that solid-state contacts between substrate and the active sites on the catalyst particles are effective in controlling reaction rates and product compositions. The results suggest that, in the early stages of coal liquefaction and hydropyrolysis, similar interactions between dispersed catalysts and coal particles may play an equally important role. RP OAK RIDGE NATL LAB, DIV CHEM, POB 2008, OAK RIDGE, TN 37831 USA. NR 33 TC 8 Z9 8 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 EI 1520-5029 J9 ENERG FUEL JI Energy Fuels PD MAY-JUN PY 1993 VL 7 IS 3 BP 373 EP 379 DI 10.1021/ef00039a007 PG 7 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA LD731 UT WOS:A1993LD73100007 ER PT J AU POLMAN, JK BRECKENRIDGE, CR DELEZENEBRIGGS, KM AF POLMAN, JK BRECKENRIDGE, CR DELEZENEBRIGGS, KM TI MICROBIOLOGICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES SO ENERGY & FUELS LA English DT Article ID LOW-RANK COAL; TRAMETES-VERSICOLOR; MICROORGANISMS; DESULFURIZATION; SOLUBILIZATION AB The microbial content of different lots of three Argonne Premium Coals (North Dakota Beulah Zap lignite, Wyodak subbituminous, and Illinois No. 6 bituminous) was analyzed using 28 kinds of growth medium incubated under aerobic, microaerobic, and anaerobic conditions. This work was initiated for the purpose of isolating microorganisms that naturally occur in coal, with the presumption that they would be valuable for coal bioconversion technology. The types of microorganisms that were targeted for cultivation included aerobes, microaerophiles, facultative and strict anaerobes, fungi, sulfate-reducing bacteria, methanogenic bacteria, and chemoheterotrophs. Media included nutrient agar and broth, yeast/mold agar and broth, lactate medium, Bacto anaerobic agar, triple sugar iron agar, selenite broth, Eugon broth, Brewer modified thioglycollate medium, thioglycollate medium without dextrose, and 11 different methanogen enrichment media containing various primary carbon sources. After a lengthy incubation period, growth was determined by turbidity and/or production of methane. Results indicated that no viable microorganisms were derived from the coal samples. Apparently these coals are rather pristine with respect to the presence of either living or dormant aerobic and anaerobic chemoheterotrophs, and methanogens. While the growth media employed for enrichments did not target all possible microorganisms, it is clear that these coals contain little or no viable biomass as part of their physical structure. These observations are interesting and surprising from an ecological perspective, and they also increase our knowledge about the physical composition of coal. RP POLMAN, JK (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,BIOTECHNOL & ENVIRONM SCI GRP,IDAHO FALLS,ID 83415, USA. NR 27 TC 2 Z9 2 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAY-JUN PY 1993 VL 7 IS 3 BP 380 EP 383 DI 10.1021/ef00039a008 PG 4 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA LD731 UT WOS:A1993LD73100008 ER PT J AU GINTER, DM SOMORJAI, GA HEINEMANN, H AF GINTER, DM SOMORJAI, GA HEINEMANN, H TI FACTORS AFFECTING THE REACTIVITY OF CHARS AND COKES DURING LOW-TEMPERATURE (640-DEGREES-C) STEAM GASIFICATION SO ENERGY & FUELS LA English DT Article ID COAL CHAR; GRAPHITE; CATALYSTS; CALCIUM AB Coal chars and petroleum cokes were prepared by low-temperature pyrolysis, both in the absence and presence of NaOH. The solids obtained were gasified with steam at 640-degrees-C, either as-prepared or after impregnation with a K-Ca oxide catalyst. The uncatalyzed steam gasification rate increases with NaOH loading, and slows with increasing time on stream due to the slow vaporization of sodium, the decrease in contact time as the char/coke is consumed, and the lower reactivity of the residue that remains. The K-Ca oxide catalyst accelerates gasification, especially for NaOH-containing solids. Pyrolysis temperature and gasification pressure had minor effects. Gasification reactivity depends on the source of carbon, which is related to the structure of the fixed carbon, and quality of catalyst dispersion. C1 LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720. NR 20 TC 13 Z9 16 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAY-JUN PY 1993 VL 7 IS 3 BP 393 EP 398 DI 10.1021/ef00039a010 PG 6 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA LD731 UT WOS:A1993LD73100010 ER PT J AU VANBERKEL, GJ QUINONES, MA QUIRKE, JME AF VANBERKEL, GJ QUINONES, MA QUIRKE, JME TI GEOPORPHYRIN ANALYSIS USING ELECTROSPRAY IONIZATION MASS-SPECTROMETRY SO ENERGY & FUELS LA English DT Article ID CAPILLARY ZONE ELECTROPHORESIS; AMMONIA CHEMICAL IONIZATION; CARBON-NUMBER GEOPORPHYRINS; ION-TRAP; STEREOCHEMICAL PROBLEMS; SUBSTITUTED PORPHYRINS; HENRYVILLE BED; ALBANY SHALE; BIOMOLECULES; TETRAPYRROLES AB The utility of electrospray ionization combined with mass spectrometry (ES-MS) for the analysis of free-base, nickel and vanadyl geoporphyrins is demonstrated. In positive ion mode, free-base alkyl-substituted porphyrins are detected as the protonated molecule, (M + H)+, while the nickel and vanadyl chelates of these same porphyrins are observed as their radical cations, M.+, as is chlorophyll a. Detection of free-base octaethylporphyrin (OEP) using continuous infusion at 1-5 muL/min required sampling as little as 1 fmol of material, while at these same flow rates 18 fmol of OEP could be detected via flow injection. Detection of 500 fmol of mesoporphyrin IX dimethyl ester injected is demonstrated using on-line reverse-phase microbore-HPLC at a solvent flow rate of 40 muL/min. ES-MS is shown to be well-suited for geoporphyrin molecular weight and carbon number determination since no fragment ions are produced by this ionization process. Accuracy in determining the relative abundances of porphyrins within geoporphyrin mixtures is demonstrated using standard solutions containing known molar ratios of OEP and free-base etioporphyrin-III (etio-III) and a total free-base porphyrin mixture isolated from Gilsonite bitumen. On-line separation/mass spectrometric detection of free-base and nickel geoporphyrin mixtures using reverse-phase microbore-HPLC/ES/MS is demonstrated with Gilsonite porphyrins. C1 FLORIDA INT UNIV,DEPT CHEM,MIAMI,FL 33199. RP VANBERKEL, GJ (reprint author), OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37831, USA. NR 51 TC 28 Z9 28 U1 1 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 MAY-JUN PY 1993 VL 7 IS 3 BP 411 EP 419 DI 10.1021/ef00039a013 PG 9 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA LD731 UT WOS:A1993LD73100013 ER PT J AU STUMP, DM ZYWICZ, E AF STUMP, DM ZYWICZ, E TI J-INTEGRAL COMPUTATIONS IN THE INCREMENTAL AND DEFORMATION PLASTICITY ANALYSIS OF SMALL-SCALE YIELDING SO ENGINEERING FRACTURE MECHANICS LA English DT Article ID INDEPENDENT INTEGRALS; CONSERVATION-LAWS; CRACK; BODY AB Detailed numerical studies of small-scale yielding in elastic power-law plastic materials under Mode I loading reveal a path dependence of the J-integral in small-strain incremental-theory plasticity calculations, while corresponding studies employing deformation-theory plasticity show no such behavior. The path dependence of the incremental-theory calculations is sensitive to the presence of T-stresses and deviates substantially from the remote elastic J-value at radial distances, r, on the order r less-than-or-equal-to CTOD (crack-tip opening displacement). A comparison of the fields predicted by the two different plasticity implementations reveals that deep within the plastic zones, stresses are in reasonable agreement over the angular interval 10-degrees < theta < 160-degrees with moderate disagreement in the regions near the crack faces. However, the predicted strains differ markedly in regions directly ahead of the tip, at approximately 60-degrees, and bordering the crack faces. The differences in J-integral behavior lie primarily in the traction-displacement-gradient term and are conjectured to arise from the integrated effects of the slight differences in stress and strain fields. C1 LAWRENCE LIVERMORE NATL LAB,POB 808,L-122,LIVERMORE,CA 94550. IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415. NR 27 TC 12 Z9 12 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0013-7944 J9 ENG FRACT MECH JI Eng. Fract. Mech. PD MAY PY 1993 VL 45 IS 1 BP 61 EP 77 DI 10.1016/0013-7944(93)90008-G PG 17 WC Mechanics SC Mechanics GA LB991 UT WOS:A1993LB99100007 ER PT J AU HUNSAKER, C GRAHAM, R TURNER, RS RINGOLD, PL HOLDREN, GR STRICKLAND, TC AF HUNSAKER, C GRAHAM, R TURNER, RS RINGOLD, PL HOLDREN, GR STRICKLAND, TC TI A NATIONAL CRITICAL LOADS FRAMEWORK FOR ATMOSPHERIC DEPOSITION EFFECTS ASSESSMENT .2. DEFINING ASSESSMENT END-POINTS, INDICATORS, AND FUNCTIONAL SUBREGIONS SO ENVIRONMENTAL MANAGEMENT LA English DT Article DE CRITICAL LOADS; ECOLOGICAL INDICATORS; END POINTS; REGIONALIZATION; ENVIRONMENTAL ASSESSMENT ID ECOLOGICAL RISK AB The United States Environment Protection Agency, with support from the US Department of Energy and the National Oceanographic and Atmospheric Administration, has been evaluating the feasibility of an effects-based (critical loads) approach to atmospheric pollutant regulation and abatement. The rationale used to develop three of the six steps in a flexible assessment framework (Strickland and others, 1992) is presented along with a discussion of a variety of implementation approaches and their ramifications. The rationale proposes that it is necessary to provide an explicit statement of the condition of the resource that is considered valuable (assessment end point) because: (1) individual ecosystem components may be more or less sensitive to deposition, (2) it is necessary to select indicators of ecosystem condition that can be objectively measured and that reflect changes in the quality of the assessment end point, and (3) acceptable status (i.e., value of indicator and quality of assessment end point at critical load) must be defined. The rationale also stresses the importance of defining the assessment regions and subregions to improve the analysis and understanding of the indicator response to deposition. Subregional definition can be based on a variety of criteria, including informed judgment or quantitative procedures. It also depends on the geographic scale at which exposure and effects models are accurate and on data availability, resolution, and quality. C1 US EPA,OFF ENVIRONM & PROC EFFECTS RES,WASHINGTON,DC 20460. US EPA,ENVIRONM RES LAB,MANTECH ENVIRONM TECHNOL INC,CORVALLIS,OR 97333. RP HUNSAKER, C (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,OAK RIDGE,TN 37831, USA. OI Hunsaker, Carolyn/0000-0002-5662-2402 NR 21 TC 8 Z9 8 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 MAY-JUN PY 1993 VL 17 IS 3 BP 335 EP 341 DI 10.1007/BF02394676 PG 7 WC Environmental Sciences SC Environmental Sciences & Ecology GA KY777 UT WOS:A1993KY77700006 ER PT J AU HICKS, B MCMILLEN, R TURNER, RS HOLDREN, GR STRICKLAND, TC AF HICKS, B MCMILLEN, R TURNER, RS HOLDREN, GR STRICKLAND, TC TI A NATIONAL CRITICAL LOADS FRAMEWORK FOR ATMOSPHERIC DEPOSITION EFFECTS ASSESSMENT .3. DEPOSITION CHARACTERIZATION SO ENVIRONMENTAL MANAGEMENT LA English DT Article DE WET DEPOSITION; DRY DEPOSITION; MICROMETEOROLOGY ID DRY DEPOSITION; NITRIC-ACID; PRECIPITATION; CHEMISTRY; SURFACES; REMOTE AB Methods are discussed for describing patterns of current wet and dry deposition under various scenarios. It is proposed that total deposition data across an area of interest are the most relevant in the context of critical loads of acidic deposition, and that the total (i.e., wet plus dry) deposition will vary greatly with the location, the season, and the characteristics of individual subregions. Wet and dry deposition are proposed to differ in such fundamental ways that they must be considered separately. Both wet and dry deposition rates are controlled by the presence of the chemical species in question in the air (at altitudes of typically several kilometers in the case of wet deposition, and in air near the surface for dry). The great differences in the processes involved lead to the conclusion that it is better to measure wet and dry deposition separately and combine these quantifications to produce ''total deposition'' estimates than to attempt to derive total deposition directly. A number of options for making estimates of total deposition to be used in critical loads assessment scenarios are discussed for wet deposition (buckets and source receptor models) and for dry deposition (throughfall, micrometeorology, surrogate surfaces and collection vessels, inference from concentrations, dry-wet ratios, and source-receptor models). C1 NOAA,ARL,DIV ATMOSPHER TURBULENCE & DIFFUS,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. US EPA,ENVIRONM RES LAB,MANTECH ENVIRONM TECHNOL INC,CORVALLIS,OR 97333. RP HICKS, B (reprint author), NOAA,AIR RESOURCES LAB,1325 E W HIGHWAY,SILVER SPRING,MD 20910, USA. NR 19 TC 13 Z9 13 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 MAY-JUN PY 1993 VL 17 IS 3 BP 343 EP 353 DI 10.1007/BF02394677 PG 11 WC Environmental Sciences SC Environmental Sciences & Ecology GA KY777 UT WOS:A1993KY77700007 ER PT J AU HOLDREN, GR STRICKLAND, TC COSBY, BJ MARMOREK, D BERNARD, D SANTORE, R DRISCOLL, CT PARDO, L HUNSAKER, C TURNER, RS AF HOLDREN, GR STRICKLAND, TC COSBY, BJ MARMOREK, D BERNARD, D SANTORE, R DRISCOLL, CT PARDO, L HUNSAKER, C TURNER, RS TI A NATIONAL CRITICAL LOADS FRAMEWORK FOR ATMOSPHERIC DEPOSITION EFFECTS ASSESSMENT .4. MODEL SELECTION, APPLICATIONS, AND CRITICAL LOADS MAPPING SO ENVIRONMENTAL MANAGEMENT LA English DT Article DE SULFATE; NITRATE; CRITICAL LOADS; MODELING; DEPOSITION STANDARDS ID EASTERN-UNITED-STATES; REGIONAL PATTERNS; ACID; ACIDIFICATION; WATER; CONSERVATION; ECOSYSTEMS AB The critical loads approach is emerging as an attractive means for evaluating the effects of atmospheric deposition on sensitive terrestrial and aquatic ecosystems. Various approaches are available for modeling ecosystem responses to deposition and for estimating critical load values. These approaches include empirical and statistical relationships, steady-state and simple process models, and integrated-effects models. For any given ecosystem, the most technically sophisticated approach will not necessarily be the most appropriate for all applications; identification of the most useful approach depends upon the degree of accuracy needed and upon data and computational requirements, biogeochemical processes being modeled, approaches used for representing model results on regional bases, and desired degree of spatial and temporal resolution. Different approaches are characterized by different levels of uncertainty. If the limitations of individual approaches are known, the user can determine whether an approach provides a reasonable basis for decision making. Several options, including point maps, grid maps, and ecoregional maps, are available for presenting model results in a regional context. These are discussed using hypothetical examples for choosing populations and damage limits. C1 UNIV VIRGINIA,DEPT ENVIRONM SCI,CHARLOTTESVILLE,VA 22903. ENVIRONM & SOCIAL SYST LTD,VANCOUVER V6J 5C6,BC,CANADA. SYRACUSE UNIV,DEPT CIVIL & ENVIRONM ENGN,SYRACUSE,NY 13244. OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. RP HOLDREN, GR (reprint author), ENVIRONM RES LAB,MANTECH ENVIRONM TECHNOL INC,200 SW 35TH ST,CORVALLIS,OR 97333, USA. RI Driscoll, Charles/F-9832-2014; Cosby, Bernard/B-5653-2012 NR 26 TC 8 Z9 10 U1 1 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0364-152X J9 ENVIRON MANAGE JI Environ. Manage. PD MAY-JUN PY 1993 VL 17 IS 3 BP 355 EP 363 DI 10.1007/BF02394678 PG 9 WC Environmental Sciences SC Environmental Sciences & Ecology GA KY777 UT WOS:A1993KY77700008 ER PT J AU DANIELS, RC WHITE, TW CHAPMAN, KK AF DANIELS, RC WHITE, TW CHAPMAN, KK TI SEA-LEVEL RISE - DESTRUCTION OF THREATENED AND ENDANGERED SPECIES HABITAT IN SOUTH-CAROLINA SO ENVIRONMENTAL MANAGEMENT LA English DT Article DE SOUTH-CAROLINA; SEA-LEVEL RISE; GREENHOUSE EFFECT; ENDANGERED SPECIES; THREATENED SPECIES; HABITAT LOSS ID GREENHOUSE AB Concern for the environment has increased over the past century, and the US Congress has responded to this concern by passing legislation designed to protect the nation's ecological biodiversity. This legislation, culminating with the Endangered Species Act of 1973, has been instrumental in defining methods for identifying and protecting endangered or threatened species and their habitats. Current legislation, however, assumes that the range of a protected species will stay constant over time. This assumption may no longer be valid, as the unprecedented increase in the number and concentration of greenhouse gases in the atmosphere has the potential to cause a global warming of 1.0-4.5-degrees-C and a sea-level rise (SLR) of 31-150 cm by the year 2100. Changes in climate of this magnitude are capable of causing shifts in the population structure and range of most animal species. This article examines the effects that SLR may have on the habitats of endangered and threatened species at three scales. At the regional scale 52 endangered or threatened plant and animal species were found to reside within 3 m of mean sea level in the coastal stages of the US Southeast. At the state level, the habitats of nine endangered or threatened animals that may be at risk from future SLR were identified. At the local level, a microscale analysis was conducted in the Cape Romain National Wildlife Refuge, South Carolina, USA, on the adverse effects that SLR may have on the habitats of the American alligator, brown pelican, loggerhead sea turtle, and wood stork. RP DANIELS, RC (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831, USA. NR 30 TC 27 Z9 30 U1 4 U2 37 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0364-152X J9 ENVIRON MANAGE JI Environ. Manage. PD MAY-JUN PY 1993 VL 17 IS 3 BP 373 EP 385 DI 10.1007/BF02394680 PG 13 WC Environmental Sciences SC Environmental Sciences & Ecology GA KY777 UT WOS:A1993KY77700010 ER PT J AU DZOMBAK, DA LABIENIEC, PA SIEGRIST, RL AF DZOMBAK, DA LABIENIEC, PA SIEGRIST, RL TI THE NEED FOR UNIFORM SOIL CLEANUP GOALS SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Editorial Material C1 CARNEGIE MELLON UNIV,DEPT ENGN,PITTSBURGH,PA 15213. CARNEGIE MELLON UNIV,DEPT PUBL POLICY,PITTSBURGH,PA 15213. OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN. RP DZOMBAK, DA (reprint author), CARNEGIE MELLON UNIV,DEPT CIVIL ENGN,PITTSBURGH,PA 15213, USA. NR 0 TC 9 Z9 9 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 MAY PY 1993 VL 27 IS 5 BP 765 EP 766 PG 2 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA LA739 UT WOS:A1993LA73900001 ER PT J AU TAYLOR, PA AF TAYLOR, PA TI AN EVALUATION OF THE TOXICITY OF VARIOUS FORMS OF CHLORINE TO CERIODAPHNIA-DUBIA SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE CHLORINE; MONOCHLORAMINE; DICHLORAMINE; CERIODAPHNIA-DUBIA; TOXICITY AB Ambient toxicity tests at 15 sites on five small streams that receive discharges from Oak Ridge National Laboratory (TN) showed that chlorine (mostly from once-through cooling water) was an important toxicant; however, there was not a good correlation between chlorine concentration and toxicity to Ceriodaphnia dubia in the ambient tests. To better understand the toxicity of chlorine, its various forms (hypochlorite ion, hypochlorous acid, monochloramine, and dichloramine) were tested individually. Standard Ceriodaphnia dubia acute toxicity tests (static, 24 h, with added food) showed that the chloramines were very toxic (LC50 < 0.02 mg/L) but that free chlorine (hypochlorous acid and hypochlorite ion) was much less toxic (LC50s of 0. 14 and 0.08 mg/L, respectively). Chlorine decay measurements in the toxicity test solutions showed that free chlorine reacts very rapidly (< 1 min) with the Ceriodaphnia dubia food (a mixture of digested trout chow, yeast, and Cerophyl(R)) added to the solutions, so the standard toxicity test measured the toxicity of chlorinated food rather than the toxicity of free chlorine. Static tests without food showed LC50s of 0.012 mg/L for monochloramine, 0.016 mg/L for dichloramine, 0.035 mg/L for hypochlorous acid, and 0.048 mg/L for hypochlorite ion; however, the free chlorine still decayed rapidly (< 7 h) in the test solution. Continuous-flow toxicity tests showed that free chlorine is more toxic than the chloramines, with LC50s of 0.005 mg/L for hypochlorous acid, 0.006 mg/L for hypochlorite ion, 0.016 for monochloramine, and 0.027 mg/L for dichloramine. The LC50s for hypochlorous acid and hypochlorite ion are substantially below the U.S. Environmental Protection Agency's 4-d average water-quality criterion for chlorine of 0.011 mg/L RP TAYLOR, PA (reprint author), OAK RIDGE NATL LAB,DIV CHEM TECHNOL,POB 2008,BLDG 3017,OAK RIDGE,TN 37831, USA. NR 9 TC 13 Z9 13 U1 1 U2 4 PU SETAC PRESS PI PENSACOLA PA 1010 NORTH 12TH AVE, PENSACOLA, FL 32501-3370 SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD MAY PY 1993 VL 12 IS 5 BP 925 EP 930 DI 10.1897/1552-8618(1993)12[925:AEOTTO]2.0.CO;2 PG 6 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA KX607 UT WOS:A1993KX60700017 ER PT J AU AHMED, FE AF AHMED, FE TI ISSUES IN FISHERY PRODUCTS SAFETY IN THE UNITED-STATES SO ENVIRONMENTAL TOXICOLOGY AND WATER QUALITY LA English DT Article AB Most seafoods available to the U.S. public are wholesome and unlikely to cause illness in the consumer. Nevertheless, there are areas of risk. The major risk of acute disease is associated with the consumption of raw shellfish, particularly bivalve molluscs. For persons living in tropical areas, there is a risk of ciguatera; other natural toxins (paralytic shellfish poisoning, neurotoxic shellfish poisoning, etc.) have been associated with shellfish from endemic areas. Finally, there are less well-defined risks of acute and chronic disease related to environmental contamination of aquatic food animals. Dealing with such risks on a short-term basis requires improvements in the present system of regulatory control. In the long term, amelioration and eventual elimination of some hazards require strengthening and more effective application of control measures to prevent the disposal of human and industrial waste into offshore marine and fresh waters. RP AHMED, FE (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 1053-4725 J9 ENVIRON TOXIC WATER JI Environ. Toxicol. Water Quality PD MAY PY 1993 VL 8 IS 2 BP 141 EP 152 DI 10.1002/tox.2530080203 PG 12 WC Environmental Sciences; Toxicology; Water Resources SC Environmental Sciences & Ecology; Toxicology; Water Resources GA KY401 UT WOS:A1993KY40100002 ER PT J AU BRENEMAN, JW YAU, P TEPLITZ, RL BRADBURY, EM AF BRENEMAN, JW YAU, P TEPLITZ, RL BRADBURY, EM TI A LIGHT-MICROSCOPE STUDY OF LINKER HISTONE DISTRIBUTION IN RAT METAPHASE CHROMOSOMES AND INTERPHASE NUCLEI SO EXPERIMENTAL CELL RESEARCH LA English DT Article ID BRAIN CORTICAL-NEURONS; POLYTENE CHROMOSOMES; CHROMATIN STRUCTURE; ACTIVE CHROMATIN; DNA-BINDING; CENP-B; CELLS; H-1; LOCALIZATION; REGIONS C1 UNIV CALIF DAVIS,SCH MED,DEPT BIOL CHEM,DAVIS,CA 95616. UNIV CALIF DAVIS,SACRAMENTO MED CTR,DEPT PATHOL,SACRAMENTO,CA 95817. LOS ALAMOS NATL LAB,DIV BIOL CHEM,LOS ALAMOS,NM 87545. FU CGH CDC HHS [GH 26901] NR 62 TC 30 Z9 32 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 0014-4827 J9 EXP CELL RES JI Exp. Cell Res. PD MAY PY 1993 VL 206 IS 1 BP 16 EP 26 DI 10.1006/excr.1993.1115 PG 11 WC Oncology; Cell Biology SC Oncology; Cell Biology GA LA655 UT WOS:A1993LA65500003 PM 8482357 ER PT J AU STOJIMIROVIC, A MAJUMDAR, S AF STOJIMIROVIC, A MAJUMDAR, S TI ANALYSIS OF THE THERMOMECHANICAL CONTACT BETWEEN BERYLLIUM BLOCKS AND STAINLESS-STEEL PLATES IN ITER DESIGN SO FUSION TECHNOLOGY LA English DT Article DE THERMOMECHANICAL CONTACT; THERMAL RESISTANCE; ITER DESIGN AB The thermomechanical contact between beryllium cubes and Type 316 stainless steel was analyzed for various values of applied pressure normal to the interface. If we neglect the influence of gap on the interface resistance, finite element analyses show that a simple one-dimensional analysis can lead to serious underestimation of the maximum temperature of the beryllium. A two-dimensional analysis underpredicts the maximum gap created at the interface, compared with a full three-dimensional analysis. Thus, it also significantly underpredicts the maximum temperature of the beryllium. RP STOJIMIROVIC, A (reprint author), ARGONNE NATL LAB,DIV MAT & COMPONENTS TECHNOL,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAY PY 1993 VL 23 IS 3 BP 309 EP 315 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KY733 UT WOS:A1993KY73300004 ER PT J AU RABEAU, M PITTS, JH MENGUE, JF MAURIN, G AF RABEAU, M PITTS, JH MENGUE, JF MAURIN, G TI GEOMETRIC ARRANGEMENT OF BEAMLETS IN LARGE LASER FUSION FACILITIES SO FUSION TECHNOLOGY LA English DT Note DE MEGAJOULE LASER; MEGAJOULE ICF FACILITY AB Geometrical arrangements for locating the large number of beamlets used in high-energy laser fusion facilities around a target chamber, suitable for the 1- to 2-MJ Phebus upgrade facility, are compared. The beamlets are clustered together and enter the target chamber area from two opposite poles. Beamlets from two different amplifier regions are interlaced around four pairs of conical surfaces, so that more symmetrical illumination of indirect drive targets is possible even when only some of the amplifiers are operational. A passive system is proposed to protect the focus lenses from X rays, ion debris, and internal target chamber pollutants. The system includes sacrificial debris shields and a static, approximately 2-m length of incondensable gas. A crosswise orientation allows for maximum operational flexibility; an in-line orientation uses three fewer mirrors per beamlet but requires a larger target chamber room and longer laser bays. Neutron protection includes concrete shielding and also an approximately 1- to 2-m-thick water shield positioned just inside the periphery of the target chamber room. Selected low-activation materials are used as much as possible inside the water shield to minimize the recovery time after a shot. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP RABEAU, M (reprint author), CEA,CTR ETUD LIMEIL VALENTON,F-94195 VILLENEUVE ST GEO,FRANCE. NR 7 TC 3 Z9 4 U1 0 U2 3 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAY PY 1993 VL 23 IS 3 BP 337 EP 341 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KY733 UT WOS:A1993KY73300009 ER PT J AU MONTICELLO, DA AF MONTICELLO, DA TI SUMMARY OF THE IAEA TECHNICAL COMMITTEE MEETING ON ADVANCES IN SIMULATION AND MODELING THERMONUCLEAR PLASMAS, MONTREAL, CANADA, JUNE 15-17, 1992 SO FUSION TECHNOLOGY LA English DT Editorial Material RP MONTICELLO, DA (reprint author), PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAY PY 1993 VL 23 IS 3 BP 362 EP 363 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KY733 UT WOS:A1993KY73300013 ER PT J AU CHUM, HL OVEREND, R PHILLIPS, JA AF CHUM, HL OVEREND, R PHILLIPS, JA TI THE GREAT ENERGY HARVEST SO FUTURIST LA English DT Article C1 JA PHILLIPS & ASSOCIATES,BOULDER,CO 80302. NATL RENEWABLE ENERGY LAB,DIV ALTERNAT FUELS,GOLDEN,CO 80401. RP CHUM, HL (reprint author), NATL RENEWABLE ENERGY LAB,DIV IND TECHNOL,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU WORLD FUTURE SOCIETY PI BETHESDA PA 7910 WOODMONT AVE, SUITE 450, BETHESDA, MD 20814 SN 0016-3317 J9 FUTURIST JI Futurist PD MAY-JUN PY 1993 VL 27 IS 3 BP 34 EP 40 PG 7 WC Social Issues SC Social Issues GA KY415 UT WOS:A1993KY41500010 ER PT J AU MITCHISON, HM THOMPSON, AD MULLEY, JC KOZMAN, HM RICHARDS, RI CALLEN, DF STALLINGS, RL DOGGETT, NA ATTWOOD, J MCKAY, TR SUTHERLAND, GR GARDINER, RM AF MITCHISON, HM THOMPSON, AD MULLEY, JC KOZMAN, HM RICHARDS, RI CALLEN, DF STALLINGS, RL DOGGETT, NA ATTWOOD, J MCKAY, TR SUTHERLAND, GR GARDINER, RM TI FINE GENETIC-MAPPING OF THE BATTEN DISEASE LOCUS (CLN3) BY HAPLOTYPE ANALYSIS AND DEMONSTRATION OF ALLELIC ASSOCIATION WITH CHROMOSOME-16P MICROSATELLITE LOCI SO GENOMICS LA English DT Article ID DINUCLEOTIDE REPEAT POLYMORPHISM; LINKAGE MAPS C1 WOMEN & CHILDRENS HOSP,DEPT CYTOGENET & MOLEC GENET,CTR MED GENET,ADELAIDE,SA 5006,AUSTRALIA. MRC,GALTON LAB,HUMAN BIOCHEM GENET UNIT,LONDON NW1 2HE,ENGLAND. LOS ALAMOS NATL LAB,DIV LIFE SCI,LOS ALAMOS,NM 87544. LOS ALAMOS NATL LAB,CTR HUMAN GENOME STUDIES,LOS ALAMOS,NM 87544. RP MITCHISON, HM (reprint author), UNIV LONDON UNIV COLL,SCH MED,DEPT PAEDIAT,RAYNE INST,UNIV ST,LONDON WC1E 6JJ,ENGLAND. RI Mitchison, Hannah/C-1891-2008; Stallings, Raymond/A-7213-2008; Sutherland, Grant/D-2606-2012; Callen, David/G-1975-2012; OI Callen, David/0000-0002-6189-9991 NR 15 TC 46 Z9 46 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0888-7543 J9 GENOMICS JI Genomics PD MAY PY 1993 VL 16 IS 2 BP 455 EP 460 DI 10.1006/geno.1993.1210 PG 6 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA LB928 UT WOS:A1993LB92800022 PM 8314582 ER PT J AU LIANG, LY MCCARTHY, JF JOLLEY, LW MCNABB, JA MEHLHORN, TL AF LIANG, LY MCCARTHY, JF JOLLEY, LW MCNABB, JA MEHLHORN, TL TI IRON DYNAMICS - TRANSFORMATION OF FE(II)/FE(III) DURING INJECTION OF NATURAL ORGANIC-MATTER IN A SANDY AQUIFER SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID OXIDE-WATER INTERFACE; COORDINATION CHEMISTRY; FERROUS IRON; SURFACE; DISSOLUTION; ADSORPTION; KINETICS; ANIONS; DELTA-AL2O3; OXYGENATION AB The dynamics of dissolved, colloidal, and deposited iron phases were examined during a forced-gradient field experiment. The experiment involved the injection of oxygenated water containing high levels of natural organic matter (NOM) into a sandy aquifer. The initial redox potential of the aquifer favored Fe(II) in the groundwater. The changes in the concentrations of Fe(II) and Fe(III) were observed in sampling wells. Under the increased dissolved oxygen (DO) conditions, Fe(II) oxygenation was rapid, resulting in the formation of Fe(III) (hydr)oxide colloids. The oxidation follows the rate law as given in STUMM and MORGAN(1981): d[Fe(II)]/dt = - k(obs)[O2(aq)]/[H+]2 [Fe(II)], with a rate constant, k(obs) to be 1.9 X 10(-12) M min-1. For an averaged pH and DO of the groundwater, the half time of Fe(II) oxidation is 49 h. The NOM was postulated to stabilize the newly formed colloids, thereby increasing the turbidity in the groundwater. The additional increase in the colloidal fraction of Fe(III) oxide suggested that transport of the colloidal particles was occurring. At those locations where DO remained constantly low, the turbidity increase was moderate, and up to 80% of Fe(III) was in the dissolved phase (<3000 mol. wt.). The latter observation was attributed to the presence of NOM, forming Fe(III)-organic complexes. In addition, NOM may play a role in the oxygen consumption through a Fe(II)/Fe(III) catalyzed oxidation of organic matter as outlined by STUMM and MORGAN (1981, p. 469). In this mechanism, Fe(II) oxidation is slow, maintaining a near constant Fe(II) concentration, in agreement with field data. The overall increase in Fe(III) under low DO conditions was postulated to be a combination of (1) slow oxidation, (2) ligand-promoted and catalytic dissolution of deposited iron phases, and (3) the transport of newly formed iron oxide colloids along flow paths. C1 CLEMSON UNIV, BARUCH FOREST SCI INST, GEORGETOWN, SC 29442 USA. RP LIANG, LY (reprint author), OAK RIDGE NATL LAB, DIV ENVIRONM SCI, POB 2008-6038, OAK RIDGE, TN 37831 USA. RI Liang, Liyuan/O-7213-2014 OI Liang, Liyuan/0000-0003-1338-0324 NR 47 TC 51 Z9 55 U1 2 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 EI 1872-9533 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD MAY PY 1993 VL 57 IS 9 BP 1987 EP 1999 DI 10.1016/0016-7037(93)90088-E PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA LC554 UT WOS:A1993LC55400006 ER PT J AU FEISS, PG VANCE, RK WESOLOWSKI, DJ AF FEISS, PG VANCE, RK WESOLOWSKI, DJ TI VOLCANIC ROCK HOSTED GOLD AND BASE-METAL MINERALIZATION ASSOCIATED WITH NEOPROTEROZOIC EARLY PALEOZOIC BACK-ARC EXTENSION IN THE CAROLINA TERRANE, SOUTHERN APPALACHIAN PIEDMONT SO GEOLOGY LA English DT Article ID SLATE BELT AB Volcanogenic mineral deposits in the Carolina terrane, southern Appalachian Piedmont, include Kuroko-type polymetallic massive sulfide deposits and disseminated gold-pyrite deposits associated with propylitic, silicic, argillic, and advanced argillic alteration. Host rocks are metavolcaniclastic and metaepiclastic rocks of a Neoproterozoic-Early Cambrian magmatic arc. The favorable gold horizon is the transition from a lower succession of andesitic and rhyolitic pyroclastic rocks with basal mafic lavas to an upper sequence of epiclastic sedimentary units and minor lava and ash flows. Kuroko-type deposits are associated with mafic to bimodal volcanic rocks in the upper sequence. Whole-rock oxygen isotope analyses indicate that gold mineralization is associated with a transition from hydrothermal systems dominated by isotopically relatively light (deltaO-18 = -6 parts-per-thousand to -10-parts-per-thousand) waters, typical of high-latitude subaerial systems, to seawater (deltaO-18 = 0 parts-per-thousand). Plots of deltaO-18 vs. SiO2 of the host rocks show a compositional gap associated with mineralization at the subaerial to submarine transition. Values of deltaO-18 for the hydrothermal waters, lithostratigraphic analyses, and tectonic models of the Carolina terrane demonstrate that mineralization coincided with extension in a rifted arc. C1 GEORGIA SO UNIV,DEPT GEOL & GEOG,STATESBORO,GA 30460. OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831. RP FEISS, PG (reprint author), UNIV N CAROLINA,DEPT GEOL,CHAPEL HILL,NC 27599, USA. NR 34 TC 15 Z9 15 U1 1 U2 1 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD MAY PY 1993 VL 21 IS 5 BP 439 EP 442 DI 10.1130/0091-7613(1993)021<0439:VRHGAB>2.3.CO;2 PG 4 WC Geology SC Geology GA LB109 UT WOS:A1993LB10900014 ER PT J AU SANDERS, CL LAUHALA, KE MCDONALD, KE SANDERS, GA AF SANDERS, CL LAUHALA, KE MCDONALD, KE SANDERS, GA TI LIFE-SPAN STUDIES IN RATS EXPOSED TO (PUO2)-PU-239 AEROSOL SO HEALTH PHYSICS LA English DT Article DE PU-239; AEROSOLS; DOSIMETRY, INTERNAL; INHALATION ID DOSE FOLLOWING INHALATION; INHALED (PUO2)-PU-239; ALVEOLAR MACROPHAGES; MOUSE LUNG; CARCINOGENESIS; RETENTION; PARTICLES; PLUTONIUM; AUTORADIOGRAPHY; PUO2-PU-239 AB Spatial-temporal dose-distribution patterns in the lung continually change following inhalation of radionuclides. Lung clearance, microdosimetry, and radiation dose were examined in female Wistar rats exposed to high-fired (Yb2O3)-Yb-169-(PuO2)-Pu-239 aerosols. Whole-body counting for Yb-169 at 14 d postexposure provided an accurate (r = 0.99) estimate of Pu-239 lung content. Alpha irradiation of tracheal epithelium was at least 50 times less than for bronchiolar epithelium due principally to preferential retention of (PuO2)-Pu-239 in peribronchiolar alveoli as compared to other alveolar regions. The formation of large aggregates (>25 particles) increased linearly with initial lung burden starting at 0.4 kBq; mean dose rate to these focal alveolar regions was 120 Gy d-1. Concentration Of (PuO2)-Pu-239 in pulmonary macrophages and in aggregates, along with the limited penetration of alpha particles in tissue, resulted in a highly nonhomogeneous dose distribution pattern. Alveolar clearance was best represented by a biphasic clearance curve comprised of a rapid early phase (80% initial lung burden) and a slow late phase (20% initial lung burden). Studies with intratracheally instilled (PuO2)-Pu-237-(PuO2)-Pu-239 and with inhaled (PuO2)-Pu-239 showed that alveolar clearance was inversely proportional to initial lung burden. A single clearance function was derived from experimentally determined clearance curves for inhaled (PuO2)-Pu-239 that was used to accurately estimate lung dose at all initial lung burden levels. Lung doses were calculated for 2,105 exposed lifespan rats based on individually determined initial lung burden, survival time, and individually computed clearance function. C1 WASHINGTON STATE UNIV, RICHLAND, WA 99352 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 51 TC 25 Z9 26 U1 1 U2 3 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD MAY PY 1993 VL 64 IS 5 BP 509 EP 521 DI 10.1097/00004032-199305000-00008 PG 13 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 KY756 UT WOS:A1993KY75600009 PM 8491602 ER PT J AU MCALPINE, S AF MCALPINE, S TI GENETIC HETEROZYGOSITY AND REPRODUCTIVE SUCCESS IN THE GREEN TREEFROG, HYLA-CINEREA SO HEREDITY LA English DT Article DE HETEROZYGOSITY; HYLA-CINEREA; HYLIDAE; LIFE HISTORY; REPRODUCTIVE SUCCESS ID ENZYME HETEROZYGOSITY; AMBYSTOMA-TIGRINUM; MYTILUS-EDULIS; EGG SIZE; GROWTH; VARIABILITY; POPULATIONS; SALAMANDERS; ADAPTATION; BEHAVIOR AB The relationship between genetic variation' and fitness characteristics is important because reduce variation at the population level is usually associated with reduced viability of individuals. Adult green treefrogs from a single population were examined at eight polymorphic allozyme loci to test the prediction that a positive correlation exists between reproductive success and number of heterozygous loci. In females, clutch size, corrected for snout-vent length, and total number of surviving offspring were significantly correlated with number of heterozygous loci. The relationship with percentage hatched showed the same correlation, but it was not significant. Body size as measured by snout-vent length was not associated with number of heterozygous loci, although larger females had significantly more hatched offspring. In males, heterozygosity was not associated with body size or hatching success of the clutch. Total reproductive success in females was positively correlated with number of heterozygous loci, while factors such as body size, which may affect fitness, were not. RP MCALPINE, S (reprint author), UNIV GEORGIA,SAVANNAH RIVER ECOL LAB,PO DRAWER E,AIKEN,SC 29802, USA. NR 26 TC 20 Z9 23 U1 1 U2 8 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0018-067X J9 HEREDITY JI Heredity PD MAY PY 1993 VL 70 BP 553 EP 558 DI 10.1038/hdy.1993.79 PN 5 PG 6 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA LB275 UT WOS:A1993LB27500014 ER PT J AU REIGNER, BG BOIS, FY TOZER, TN AF REIGNER, BG BOIS, FY TOZER, TN TI PENTACHLOROPHENOL CARCINOGENICITY - EXTRAPOLATION OF RISK FROM MICE TO HUMANS SO HUMAN & EXPERIMENTAL TOXICOLOGY LA English DT Article ID CHLORINATED PHENOLS; METABOLISM; PHARMACOKINETICS; TOXICITY; TETRACHLOROHYDROQUINONE; BINDING; URINE AB 1 Pentachlorophenol (PCP) has been found to be carcinogenic in mice. The objective of this study was to extrapolate to humans the risk of cancer from data obtained in mice using information on disposition, serum protein binding and metabolism of PCP across species. 2 A review of the literature indicates that neither PCP nor a mutagenic metabolite, tetrachlorohydroquinone (TCHQ), has been specifically identified as responsible for the carcinogenicity. In addition, the occurrence of TCHQ as a metabolite of PCP in humans is still questionable. Therefore, cancer risk assessment is performed on the assumption that PCP itself is responsible for the carcinogenicity. 3 For interspecies extrapolation, a new method in which interspecies differences in clearance and serum protein binding are taken into account is used. The method gives estimates of equivalent human doses of PCP which are up to 4 times smaller than those obtained using body surface area. For both interspecies extrapolation methods, the estimated virtually-safe doses of PCP are smaller than the average daily intakes reported in groups of subjects nonspecifically exposed to PCP. Corresponding extra risks of cancer for lifetime exposure are from 20 to 140 times greater than the acceptable extra risk (10(-6)). The results obtained with this approach indicate that PCP is a possible public health hazard. C1 UNIV CALIF SAN FRANCISCO,SCH PHARM,DEPT PHARM,SAN FRANCISCO,CA 94143. LAWRENCE BERKELEY LAB,INDOOR ENVIRONM PROGRAM,BERKELEY,CA 94720. RI Bois, Frederic/E-9241-2012 OI Bois, Frederic/0000-0002-4154-0391 FU NIEHS NIH HHS [ES 04705] NR 51 TC 13 Z9 13 U1 0 U2 3 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE, HAMPSHIRE, ENGLAND RG21 6XS SN 0144-5952 J9 HUM EXP TOXICOL JI Hum. Exp. Toxicol. PD MAY PY 1993 VL 12 IS 3 BP 215 EP 225 PG 11 WC Toxicology SC Toxicology GA LC049 UT WOS:A1993LC04900004 PM 8100432 ER PT J AU CHANG, JJ CHRISTIANSEN, WH AF CHANG, JJ CHRISTIANSEN, WH TI WAVE-GUIDE CO2-LASERS PUMPED BY BROAD-BAND RADIATION SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article ID GAS-LASER; RESONATORS; MIRRORS; LOSSES AB A quasi-CW CO2 laser system pumped transversely by broad-band radiation from high-temperature tantalum foils was developed in the laboratory for investigating the feasibility of a space-based solar-pumped laser system. Large-bore metal-dielectric waveguides (5 and 8 mm) using sapphire were successfully applied in this system because of better energy extraction and smaller cavity losses. Computational modeling of source pumping power and laser gain were performed based on radiative transfer equations and vibrational mode analysis. Parametric scaling studies for optimizing system efficiency were conducted through both modeling and experiments. The authors found that the enhancement of pumping efficiency can be achieved by utilizaton of higher gas pressure and more CO2 isotopes. Increase of optimum gas pressure from 7.5 to 50 torr was obtained by applying higher pumping temperature and lower gas temperature, which led to a power increase from 30 mW to 1.5 W. It is also found that a smaller waveguide generates about the same output as a bigger waveguide but at higher optimum gas pressure. Computational modeling using two CO2 isotopes demonstrates higher laser gain due to near-resonant energy transfer between different isotopes. The use of a gas mixture with 6% (CO2)-C-12-O-16 and 15% (CO2)-C-13-O-16 increases the laser power by about 40%. An output of 2.7 W has been obtained with this system at a gas pressure of 70 torr. A laser efficiency of more than 20% was obtained and an estimated system efficiency of 11% or better is predicted. C1 UNIV WASHINGTON,AEROSP & ENERGET RES PROGRAM,SEATTLE,WA 98195. RP CHANG, JJ (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 31 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 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD MAY PY 1993 VL 29 IS 5 BP 1412 EP 1422 DI 10.1109/3.236156 PG 11 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA LL311 UT WOS:A1993LL31100019 ER PT J AU GOVER, JE AF GOVER, JE TI ANALYSIS OF UNITED-STATES SEMICONDUCTOR COLLABORATION SO IEEE TRANSACTIONS ON ENGINEERING MANAGEMENT LA English DT Article AB U.S. consortia and the National Science Foundation's Engineering Research Centers have often emphasized long-range research with considerably less focus on today's problems than have consortia in Japan. In most instances, these U.S. institutions have searched for revolutionary technology advancements and have had difficulty transferring their work to their members. While this type of work supports the development of new technology, it does little to solve today's competitiveness problems. Only Semiconductor Manufacturing Technology, Inc. (SEMATECH) has assisted its members with continuous improvements, compressing product cycles, establishing relationships with suppliers, and strengthening core competencies while emphasizing work leading to process and product improvements. SEMATECH's success shows that government can use SEMATECH as a model for the creation of programs where U.S. industry lags behind foreign competitors. C1 OFF SENATOR ROTH,WASHINGTON,DC 20510. RP GOVER, JE (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 54 TC 7 Z9 7 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 0018-9391 J9 IEEE T ENG MANAGE JI IEEE Trans. Eng. Manage. PD MAY PY 1993 VL 40 IS 2 BP 104 EP 113 DI 10.1109/17.277402 PG 10 WC Business; Engineering, Industrial; Management SC Business & Economics; Engineering GA LN525 UT WOS:A1993LN52500001 ER PT J AU WONG, YF POSNER, EC AF WONG, YF POSNER, EC TI A NEW CLUSTERING-ALGORITHM APPLICABLE TO MULTISPECTRAL AND POLARIMETRIC SAR IMAGES SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article ID CLASSIFICATION; CALIBRATION AB We describe an application of a scale-space clustering algorithm to the classification of a multispectral and polarimetric SAR image of an agricultural site. After the initial polarimetric and radiometric calibration and noise cancellation, we extracted a 12-dimensional feature vector for each pixel from the scattering matrix. The clustering algorithm was able to partition a set of unlabeled feature vectors from 13 selected sites, each site corresponding to a distinct crop, into 13 clusters without any supervision. The cluster parameters were then used to classify the whole image. The classification map is much less noisy and more accurate than those obtained by hierarchical rules. Starting with every point as a cluster, the algorithm works by melting the system to produce a tree of clusters in the scale space. It can cluster data in any multidimensional space and is insensitive to variability in cluster densities, sizes and ellipsoidal shapes. This algorithm, more powerful than existing ones, may be useful for remote sensing for land use. C1 CALTECH,DEPT ELECT ENGN,PASADENA,CA 91125. JET PROP LAB,PASADENA,CA 91109. RP WONG, YF (reprint author), LAWRENCE LIVERMORE NATL LAB,INST SCI COMP RES,LIVERMORE,CA 94551, USA. NR 26 TC 40 Z9 43 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 1993 VL 31 IS 3 BP 634 EP 644 DI 10.1109/36.225530 PG 11 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA LQ901 UT WOS:A1993LQ90100012 ER PT J AU STEARNS, SD TAN, LZ MAGOTRA, N AF STEARNS, SD TAN, LZ MAGOTRA, N TI LOSSLESS COMPRESSION OF WAVE-FORM DATA FOR EFFICIENT STORAGE AND TRANSMISSION SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article ID SEISMIC DATA AB This paper describes a technique for lossless waveform data compression. The technique consists of two stages. The first stage is a modified form of linear prediction with discrete coefficients and the second stage is bi-level sequence coding. The linear predictor generates an error or residue sequence in a way such that exact reconstruction of the original data sequence can be accomplished with a simple algorithm. The residue sequence is essentially white Gaussian with seismic or other similar waveform data [1]-[3]. Bi-level sequence coding, in which two sample sizes are chosen and the residue sequence is encoded into subsequences that alternate from one level to the other, further compresses the residue sequence. The principal feature of the two-stage data compression algorithm is that it is lossless, that is, it allows exact, bit-for-bit recovery of the original data sequence. The performance of the lossless compression algorithm at each stage is analyzed. The advantages of using bi-level sequence coding in the second stage are its simplicity of implementation, its effectiveness on data with large amplitude variations, and its near-optimal performance in encoding Gaussian sequences. Applications of the two-stage technique to typical seismic data indicates that an average number of compressed bits per sample close to the lower bound is achievable in practical situations. C1 UNIV NEW MEXICO,DEPT ELECT & COMP ENGN,ALBUQUERQUE,NM 87131. RP STEARNS, SD (reprint author), SANDIA NATL LABS,TECH STAFF,ALBUQUERQUE,NM 87185, USA. NR 20 TC 32 Z9 32 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 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 1993 VL 31 IS 3 BP 645 EP 654 DI 10.1109/36.225531 PG 10 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA LQ901 UT WOS:A1993LQ90100013 ER PT J AU MULJADI, E ZHAO, YF LIU, TH LIPO, TA AF MULJADI, E ZHAO, YF LIU, TH LIPO, TA TI ADJUSTABLE AC CAPACITOR FOR A SINGLE-PHASE INDUCTION-MOTOR SO IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS LA English DT Article; Proceedings Paper CT 1991 ANNUAL MEETING OF THE INDUSTRY APPLICATIONS SOC OF THE IEEE CY SEP 28-OCT 04, 1991 CL DEARBORN, MI SP IEEE, IND APPLICAT SOC AB The most common practice for starting a single-phase induction machine (SPIM) is to install a starting capacitor in series with the auxiliary winding. In some applications, two capacitors are used. One is used during the starting period to help create the starting torque. The other one is used during the running condition to improve efficiency. This paper discusses the possibility of using an electronic switch in parallel with the running capacitor, thereby providing the equivalent of a starting capacitor. The capacitor is shorted during each cycle to vary the effective size of the ac capacitor. By using this method, only one capacitor is used for both the starting and running condition, and a similar starting performance can be obtained when compared with the conventional method using two capacitors. C1 NATL TAIWAN INST TECHNOL,DEPT ELECT ENGN,TAIPEI,TAIWAN. UNIV WISCONSIN,DEPT ELECT & COMP ENGN,MADISON,WI 53706. RP MULJADI, E (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 3 TC 44 Z9 45 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 0093-9994 J9 IEEE T IND APPL JI IEEE Trans. Ind. Appl. PD MAY-JUN PY 1993 VL 29 IS 3 BP 479 EP 485 DI 10.1109/28.222415 PG 7 WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic SC Engineering GA LL502 UT WOS:A1993LL50200002 ER PT J AU VERDERBER, RR MORSE, OC ALLING, WR AF VERDERBER, RR MORSE, OC ALLING, WR TI HARMONICS FROM COMPACT FLUORESCENT LAMPS SO IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS LA English DT Article; Proceedings Paper CT 1991 ANNUAL MEETING OF THE INDUSTRY APPLICATIONS SOC OF THE IEEE CY SEP 28-OCT 04, 1991 CL DEARBORN, MI SP IEEE, IND APPLICAT SOC AB Measured characteristics of compact fluorescent lamps (CFL's) and incandescent lamps with diode-type devices have low power factor (47 to 67%) and/or high total harmonic distortion (100% THD). There is little effect on a building's power quality if the CFL's comprise less than 10% of the buildings' load. Even if the CFL is as high as 26% of the building's load, the voltage distortion is less than 5%. Circuits and their estimated costs are presented to correct for power factor and suppress the harmonics. C1 LMP CORP,DIABLO SCI LABS,DANVILLE,CA 94526. RP VERDERBER, RR (reprint author), LAWRENCE BERKELEY LAB,LIGHTENING SYST RES GRP,BERKELEY,CA 94720, USA. NR 4 TC 36 Z9 38 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 0093-9994 J9 IEEE T IND APPL JI IEEE Trans. Ind. Appl. PD MAY-JUN PY 1993 VL 29 IS 3 BP 670 EP 674 DI 10.1109/28.222443 PG 5 WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic SC Engineering GA LL502 UT WOS:A1993LL50200030 ER PT J AU BELZER, DB KELLOGG, MA AF BELZER, DB KELLOGG, MA TI INCORPORATING SOURCES OF UNCERTAINTY IN FORECASTING PEAK POWER LOADS - A MONTE-CARLO ANALYSIS USING THE EXTREME VALUE DISTRIBUTION SO IEEE TRANSACTIONS ON POWER SYSTEMS LA English DT Article ID BOOTSTRAP; JACKKNIFE AB In this paper the extreme value distribution (EVD), in conjunction with Monte Carlo simulations, is used to analyze sources of uncertainty in forecasting annual peak power loads. The methodology is applied to 1984-1986 load and weather data for a public utility district near Spokane, Washington. The methodology embodies a four-step approach: 1) estimate a weather-sensitive daily peak load model, 2) simulate historical peak loads, 3) estimate the parameters of an extreme value distribution, and 4) predict the probability points associated with different forecast horizons. Monte Carlo analysis is used to incorporate the uncertainty of the disturbances in the estimated daily load model. A separate EVD is estimated for each Monte Carlo simulation, and then the estimated EVDs are used to derive a composite distribution. Corrections are made for the small sample bias in Maximum Likelihood estimates of the EVD parameters. A bootstrapping technique extends the procedure to examine the uncertainty of the daily load model's structural parameters. C1 RESOURCE MANAGEMENT INT, PORTLAND, OR USA. RP BELZER, DB (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 20 TC 10 Z9 10 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0885-8950 J9 IEEE T POWER SYST JI IEEE Trans. Power Syst. PD MAY PY 1993 VL 8 IS 2 BP 730 EP 737 DI 10.1109/59.260807 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA LH396 UT WOS:A1993LH39600044 ER PT J AU PARKS, HG OHANLON, JF AF PARKS, HG OHANLON, JF TI RESEARCH ACCOMPLISHMENTS AT THE UNIVERSITY-OF-ARIZONA SEMATECH CENTER OF EXCELLENCE FOR CONTAMINATION DEFECT ASSESSMENT AND CONTROL SO IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING LA English DT Article AB The Arizona SEMATECH Center of Excellence (SCOE) was established in May of 1988, is funded by SEMATECH and contractually monitored by the Semiconductor Research Corporation (SRC). The SCOE is engaged in research in a broad front to understand and control contamination which causes yield limiting defects in submicron ULSI circuits. Sandia National Laboratory personnel are integrated with UA personnel in the SCOE research. The focus of the research is on contaminants, both particulates and homogeneous or distributed, which originate in, are caused by, or are transported and deposited by process gases and chemicals or process equipment. Further, the work involves investigating the mapping from contaminants and contaminant levels to degradation of device properties. The resulting degradation in device properties can then be used to estimate the effects of such contaminants for submicron processes and circuits. Results achieved during the four years of the SCOE's existence are describe in this paper. C1 UNIV ARIZONA,SEMATECH CTR EXCELLENCE DEFECT CONTAMINATING ASSESSMENT & CONTROL,TUCSON,AZ 85721. UNIV ARIZONA,DEPT CHEM ENGN,TUCSON,AZ 85721. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP PARKS, HG (reprint author), UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ 85721, USA. NR 17 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 0894-6507 J9 IEEE T SEMICONDUCT M JI IEEE Trans. Semicond. Manuf. PD MAY PY 1993 VL 6 IS 2 BP 134 EP 142 DI 10.1109/66.216932 PG 9 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA LF870 UT WOS:A1993LF87000008 ER PT J AU JANG, JSR AF JANG, JSR TI ANFIS - ADAPTIVE-NETWORK-BASED FUZZY INFERENCE SYSTEM SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS LA English DT Article ID LOGIC CONTROLLER; APPROXIMATION AB The architecture and learning procedure underlying ANFIS (adaptive-network-based fuzzy inference system) is presented, which is a fuzzy inference system implemented in the framework of adaptive networks. By using a hybrid learning procedure, the proposed ANFIS can construct an input-output mapping based on both human knowledge (in the form of fuzzy if-then rules) and stipulated input-output data pairs. In the simulation, the ANFIS architecture is employed to model nonlinear functions, identify nonlinear components on-linely in a control system, and predict a chaotic time series, all yielding remarkable results. Comparisons with artificial neural networks and earlier work on fuzzy modeling are listed and discussed. Other extensions of the proposed ANFIS and promising applications to automatic control and signal processing are also suggested. C1 UNIV CALIF BERKELEY,ELECTR RES LAB,BERKELEY,CA 94720. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP JANG, JSR (reprint author), UNIV CALIF BERKELEY,DEPT ELECT ENGN & COMP SCI,BERKELEY,CA 94720, USA. OI JANG, JYH-SHING/0000-0002-7319-9095 NR 67 TC 5233 Z9 5460 U1 35 U2 233 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9472 J9 IEEE T SYST MAN CYB JI IEEE Trans. Syst. Man Cybern. PD MAY-JUN PY 1993 VL 23 IS 3 BP 665 EP 685 DI 10.1109/21.256541 PG 21 WC Computer Science, Cybernetics; Engineering, Electrical & Electronic SC Computer Science; Engineering GA MF089 UT WOS:A1993MF08900003 ER PT J AU STANSFIELD, SA AF STANSFIELD, SA TI EXPERIMENTS IN ROBOTIC SENSORIMOTOR CONTROL DURING GRASP SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS LA English DT Letter ID PRECISION GRIP AB A series of experiments is presented, using a robot manipulator, which attempt to reproduce human sensorimotor control during grasping. The work utilizes a multifingered, dextrous robot hand equipped with a fingertip force sensor to explore dynamic grasp force adjustment during manipulation. The work is primarily concerned with the relationship between the weight of an object and the grasp force required to lift it. Too weak a grasp is unstable and the object will slip from the hand. Too strong a grasp may damage the object and/or the manipulator. An algorithm is presented which reproduces observed human behavior during grasp-and-lift tasks. The algorithm uses tactile information from the sensor to dynamically adjust the grasp force during lift. It is assumed that there is no a priori knowledge about the object to be manipulated. The effects of different arm/band postures and object surfaces is explored. Finally, the use of sensory data to detect unexpected object motion and to signal transitions between manipulation phases-with the coincident triggering of new motor programs-is investigated. RP STANSFIELD, SA (reprint author), SANDIA NATL LABS,CTR INTELLIGENT SYST & ROBOT,ALBUQUERQUE,NM 87185, USA. NR 15 TC 4 Z9 4 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9472 J9 IEEE T SYST MAN CYB JI IEEE Trans. Syst. Man Cybern. PD MAY-JUN PY 1993 VL 23 IS 3 BP 891 EP 896 DI 10.1109/21.256561 PG 6 WC Computer Science, Cybernetics; Engineering, Electrical & Electronic SC Computer Science; Engineering GA MF089 UT WOS:A1993MF08900023 ER PT J AU DAIRKEE, S HEID, HW AF DAIRKEE, S HEID, HW TI CYTOKERATIN PROFILE OF IMMUNOMAGNETICALLY SEPARATED EPITHELIAL SUBSETS OF THE HUMAN MAMMARY-GLAND SO IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY-ANIMAL LA English DT Article DE IMMUNOMAGNETIC SORTING; HUMAN MAMMARY EPITHELIUM; LUMINAL CYTOKERATINS; BASAL CYTOKERATINS; 2-DIMENSIONAL SDS-PAGE ID LYMPHOBLASTIC-LEUKEMIA ANTIGEN; HUMAN-BONE MARROW; RESOLUTION 2-DIMENSIONAL ELECTROPHORESIS; MONOCLONAL-ANTIBODIES; MYOEPITHELIAL CELLS; MAGNETIC MICROSPHERES; KERATIN EXPRESSION; BREAST-CANCER; BASAL CELLS; TUMORS AB We have used enzymatic and immunomagnetic techniques for the physical separation of the basal and luminal epithelium of the human mammary gland. Immediately after tissue dissociation and cell sorting, we have examined the steady-state CK composition of these cells individually by direct two-dimensional gel electrophoresis of intermediate filament extracts. Our results demonstrate that cytokeratins typical of simple and stratified epithelial cells are simultaneously expressed by both mammary epithelial subclasses in vivo. Moreover, the entire spectrum of cytokeratins seen in vivo is also maintained in short-term cultures of human mammary epithelium. A comparison of the data obtained by direct cytokeratin analysis with published indirect immunolocalization studies is presented. The ability to isolate purified epithelial subsets from normal human breast tissue by a simple immunomagnetic procedure demonstrated here can facilitate the development of relevant model systems for studying the regulatory components in growth, differentiation and malignant transformation of the human breast. C1 GERMAN CANC RES CTR,INST CELL & TUMOR BIOL,W-6900 HEIDELBERG,GERMANY. RP DAIRKEE, S (reprint author), LAWRENCE BERKELEY LAB,DIV LIFE SCI,1 CYCLOTRON RD,MAILSTOP 934-47A,BERKELEY,CA 94720, USA. RI Dairkee, Shanaz/D-6743-2012 NR 40 TC 21 Z9 21 U1 0 U2 0 PU SOC IN VITRO BIOLOGY PI UPPER MARLBORO PA 9315 LARGO DR W #255, UPPER MARLBORO, MD 20774-4755 SN 1071-2690 J9 IN VITRO CELL DEV-AN JI In Vitro Cell. Dev. Biol.-Anim. PD MAY PY 1993 VL 29A IS 5 BP 427 EP 432 PG 6 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA LJ342 UT WOS:A1993LJ34200017 PM 7686143 ER PT J AU YOUNG, KD OZGUNER, U AF YOUNG, KD OZGUNER, U TI FREQUENCY SHAPING COMPENSATOR DESIGN FOR SLIDING MODE SO INTERNATIONAL JOURNAL OF CONTROL LA English DT Article ID SYSTEMS AB In this paper, compensator dynamics are introduced in sliding mode through a new class of switching surfaces which has the interpretation of linear operators. Two design methods are presented, the first is based on pole placement, whereas the second is based on frequency-shaped quadratic optimal control formulation. The compensators are designed to attenuate the frequency contents of the sliding mode dynamics such that unmodelled dynamics are minimally excited. The design method using frequency shaping is applied to the control of a flexible link robot arm. Simulation results show that the excitation of the link deformations are minimized while preserving the insensitivity of the sliding mode. C1 OHIO STATE UNIV,DEPT ELECT ENGN,COLUMBUS,OH 43210. RP YOUNG, KD (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. RI Ozguner, Umit/A-4523-2008 NR 9 TC 91 Z9 92 U1 0 U2 7 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0020-7179 J9 INT J CONTROL JI Int. J. Control PD MAY PY 1993 VL 57 IS 5 BP 1005 EP 1019 DI 10.1080/00207179308934427 PG 15 WC Automation & Control Systems SC Automation & Control Systems GA LB774 UT WOS:A1993LB77400001 ER PT J AU BOHN, MS DAVIS, SH AF BOHN, MS DAVIS, SH TI THERMOCAPILLARY BREAKDOWN OF FALLING LIQUID-FILMS AT HIGH REYNOLDS-NUMBERS SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article AB This paper presents a new correlation in which the heat flux required to break a falling liquid film can be determined from the film Reynolds number. The correlation is based on the balance of local forces in the substrate region for high-Reynolds number films. Validation of the correlation required experimental data for breakdown of wavy liquid films at a significantly higher Reynolds number and heat flux than have been presented in the past. These data are also presented in the paper. The results show that the correlation collapses the experimental data for three liquids with widely varying physical properties at film Reynolds numbers at up to about 10(4). This correlation gives one the ability to predict the thermocapillary breakdown of wavy falling films at high Reynolds number, high heat flux, and over a wide range of fluid properties. C1 NORTHWESTERN UNIV,DEPT ENGN SCI & APPL MATH,EVANSTON,IL 60208. RP BOHN, MS (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. RI Davis, Stephen /B-7344-2009 NR 12 TC 16 Z9 20 U1 0 U2 1 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 MAY PY 1993 VL 36 IS 7 BP 1875 EP 1881 DI 10.1016/S0017-9310(05)80175-9 PG 7 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA LA335 UT WOS:A1993LA33500019 ER PT J AU HIXSON, RS WINKLER, MA AF HIXSON, RS WINKLER, MA TI THERMOPHYSICAL PROPERTIES OF LIQUID PLATINUM SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article; Proceedings Paper CT 3RD WORKSHOP ON SUBSECOND THERMOPHYSICS CY SEP 17-18, 1992 CL GRAZ, AUSTRIA SP BUNDESMINIST WISSENSCH & FORSCH, TECH UNIV GRAZ, PROV STYRIA, CITY GRAZ, AVL GRAZ, SIEMENS MATSUSHITA COMPONENTS OHG DEUTSCHLANDSBERG, SWAROVASKI OPT, DEWETRON, INTERUNFALL RAS VERSICHER, PHILIPS IND GMBH LEBRING DE DENSITY; ELECTRICAL RESISTIVITY; ENTHALPY; PLATINUM; PULSE HEATING; SOUND VELOCITY; TEMPERATURE AB Material properties of liquid metals are inherently difficult to measure. Static measurements are difficult to make on most metals because of the typically high values of critical temperature and pressure, problems with sample-container contamination, and physical strength limits of high-pressure vessels. Data on thermophysical properties of metals are needed for a variety of applications, and measurements on most liquid metals are performed using dynamic techniques. Dynamic pulse heating experiments are typically performed on nanosecond to millisecond timescales, providing data that would not otherwise be obtainable. We use a resistive pulse heating method to reach high-temperature expanded liquid-metal states at a constant pressure. This technique can be used for a variety of metals and allows accurate data to be obtained over a wide range of temperature. Metallic wire-shaped samples (1 x 25 mm) are resistively heated in an inert gas atmosphere for a period of about 10(-4) s by an almost-square current pulse (approximately 15 x 10(3) A). Samples expand along an isobaric path, with remote diagnostics providing data on current, voltage. temperature, volume, and sound speed. These basic quantities are then used to calculate several derivative quantities. We report measurements of enthalpy, temperature. volume, electrical resistivity, and sound velocity of liquid platinum for temperatures from the melting point up to approximately 5100 K. RP HIXSON, RS (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 6 TC 23 Z9 23 U1 0 U2 4 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD MAY PY 1993 VL 14 IS 3 BP 409 EP 416 DI 10.1007/BF00566040 PG 8 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA LL302 UT WOS:A1993LL30200007 ER PT J AU LIU, CT KUMAR, KS AF LIU, CT KUMAR, KS TI ORDERED INTERMETALLIC ALLOYS .1. NICKEL AND IRON ALUMINIDES SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Review ID INTERGRANULAR HYDROGEN EMBRITTLEMENT; ANOMALOUS YIELD BEHAVIOR; GRAIN-BOUNDARY CHEMISTRY; BORON-DOPED NI3AL; BASE L12 ALLOYS; ENVIRONMENTAL EMBRITTLEMENT; MECHANICAL-PROPERTIES; TEMPERATURE DUCTILITY; TESTING ENVIRONMENT; COMPOUND NI3AL AB This article summarizes recent progress in research and development on nickel and iron aluminide intermetallic alloys. Ordered intermetallics possess attractive properties for structural applications at elevated temperatures in hostile environments; however, brittle failure and poor fracture resistance limit their use as engineering materials. In recent years, efforts to understand this brittle fracture behavior have identified both intrinsic and extrinsic factors governing brittle fracture. Parallel work on alloy design using physical metallurgy principles has led to the development of aluminide alloys with improved mechanical and metallurgical properties for structural use. RP LIU, CT (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831, USA. OI Liu, Chain Tsuan/0000-0001-7888-9725 NR 123 TC 80 Z9 85 U1 0 U2 13 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD MAY PY 1993 VL 45 IS 5 BP 38 EP 44 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA LB547 UT WOS:A1993LB54700008 ER PT J AU CHADDA, S DATYE, A DAWSON, LR AF CHADDA, S DATYE, A DAWSON, LR TI MICROSTRUCTURAL EVALUATION OF STRAINED MULTILAYER INASSB/INSB INFRARED DETECTORS BY TRANSMISSION ELECTRON-MICROSCOPY SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID LAYER SUPERLATTICES; HETEROSTRUCTURES; EPITAXY; GROWTH AB InSb/InAsSb strained layer superlattices (SLS) were grown on (001) InSb substrates by molecular beam epitaxy at 425-degrees-C. The active device consisted of an InAs0.15Sb0.85/InSb superlattice region embedded within a p-i-n junction. The large lattice mismatch between the active device and the substrate required the growth of a buffer. InAs0.15Sb0.85/InSb SLS, where the average As content was gradually increased, was used as a buffer. The buffer structure was varied to probe its microstructural effect on the capping device. Three distinct approaches (A, B, and C) were used to grow the buffer. Approach A was a four-step buffer where the average content of As in the superlattice was increased in four equal composition steps. This approach led to a crystal with an extensive network of threading dislocations and microcracks. Approach B was to change the average composition in five equal composition steps, thereby decreasing the misfit at the interfaces between composition steps. This led to a decrease in the threading dislocation density but microscopic cracks were still evident. The last approach (C) was to employ migration enhanced epitaxy (MEE) for the growth of the five-step buffer. Samples grown by employing MEE revealed no microcracks but they contained a high density of unusual ''wiggly'' dislocations at the buffer/device interface. Detailed microstructural analysis by transmission electron microscopy is presented. C1 UNIV NEW MEXICO,DEPT CHEM ENGN,ALBUQUERQUE,NM 87131. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. OI Datye, Abhaya/0000-0002-7126-8659 NR 17 TC 5 Z9 5 U1 0 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 MAY 1 PY 1993 VL 73 IS 9 BP 4232 EP 4239 DI 10.1063/1.352802 PG 8 WC Physics, Applied SC Physics GA LA320 UT WOS:A1993LA32000015 ER PT J AU NILES, DW RIOUX, D HOCHST, H AF NILES, DW RIOUX, D HOCHST, H TI A PHOTOEMISSION INVESTIGATION OF THE SNO2/CDS INTERFACE - A FRONT CONTACT INTERFACE STUDY OF CDS/CDTE SOLAR-CELLS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TIN OXIDE-FILMS; CDTE; COATINGS AB A frequently used front contact in CdS/CdTe heterojunction solar cells is SnO2. We have performed a soft x-ray synchrotron radiation photoemission investigation of the formation and thermal stability of the SnO2/CdS interface in an attempt to understand how device processing influences this interface. The most important results are that (1) the CdS and SnO2 do not interact chemically, even after annealing to 400-degrees-C, (3) the first approximately 16 angstrom CdS deposited on polycrystalline SnO2 grows in a layer-by-layer mode, (3) subsequent CdS layers agglomerate, forming a topologically rough surface, (4) diffusion of Sn, Cd, and S across the interface does not occur, (5) annealing a CdS thin film grown at room temperature on SnO2 to 400-degrees-C enhances the agglomeration, and (6) the near coincidence of the conduction-band minimum across the interface facilitates ohmic contact between n-type CdS and n-type SnO2. C1 UNIV WISCONSIN MADISON,CTR SYCHROTRON RADIAT,STOUGHTON,WI 53589. RP NILES, DW (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 28 TC 23 Z9 24 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1993 VL 73 IS 9 BP 4586 EP 4590 DI 10.1063/1.352748 PG 5 WC Physics, Applied SC Physics GA LA320 UT WOS:A1993LA32000071 ER PT J AU HUNG, CY BAO, XJ SCHLESINGER, TE JAMES, RB CHENG, AY ORTALE, C VANDENBERG, L AF HUNG, CY BAO, XJ SCHLESINGER, TE JAMES, RB CHENG, AY ORTALE, C VANDENBERG, L TI INTRODUCTION OF EXTRINSIC DEFECTS INTO MERCURIC IODIDE DURING PROCESSING SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID PHOTOLUMINESCENCE SPECTRUM; DETECTORS AB Low temperature (4.2 K) photoluminescence spectroscopy (PL) measurements were performed on mercuric iodide (HgI2) crystals which were intentionally doped with copper or silver during KI etching. PL spectra obtained after these doping experiments show specific Cu and Ag features similar to those previously observed after deposition of Cu or Ag contacts on mercuric iodide crystals. The in-diffusion of Cu or Ag into bulk HgI2 has also been confirmed a few days after doping. This diffusion introduces new recombination centers in the material. This work suggests that the processing steps used to fabricate mercuric iodide nuclear detectors can lead to the introduction of new defects which are detrimental to detector performance. C1 SANDIA NATL LABS,DIV ADV MAT RES,LIVERMORE,CA 94550. EG&G ENERGY MEASUREMENTS INC,GOLETA,CA 93116. RP HUNG, CY (reprint author), CARNEGIE MELLON UNIV,DEPT ELECT & COMP ENGN,PITTSBURGH,PA 15213, USA. NR 19 TC 7 Z9 7 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1993 VL 73 IS 9 BP 4591 EP 4594 DI 10.1063/1.352749 PG 4 WC Physics, Applied SC Physics GA LA320 UT WOS:A1993LA32000072 ER PT J AU WOODWARD, J TATE, J HERRMANN, PC EVANS, BR AF WOODWARD, J TATE, J HERRMANN, PC EVANS, BR TI COMPARISON OF ELLMANS REAGENT WITH N-(1-PYRENYL)MALEIMIDE FOR THE DETERMINATION OF FREE SULFHYDRYL-GROUPS IN REDUCED CELLOBIOHYDROLASE-I FROM TRICHODERMA-REESEI SO JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS LA English DT Article DE ELLMANS REAGENT; N-(1-PYRENYL)MALEIMIDE; SULFHYDRYL DETERMINATION; CELLOBIOHYDROLASE-I ID DISULFIDE BRIDGES AB The enzyme cellobiohydrolase I (CBH I) from Trichoderma reesei was treated with 5 mM dithiothreitol at different pH values in order to reduce some or all of its 12 disulfide bridges. A discrepancy was found in the number of free sulfhydryl (SH) groups generated upon the reduction of CBH I when they were measured using N-(1-pyrenyl)maleimide (PM) or Ellman's reagent, 5,5'-dithiobis(2-nitrobenzoic acid). For example, the number of SH mol generated/mol CBH I at pH 8.5 was determined to be 16 and <1 when measured using PM or Ellman's reagent, respectively. The low value obtained with Ellman's reagent may be due to the electrostatic repulsion between the carboxylic acid groups in CBH I and those in Ellman's reagent. The fluorimetric assay used for determining SH molecules in reduced CBH I, based on their reaction with PM, is described. RP WOODWARD, J (reprint author), OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831, USA. NR 16 TC 12 Z9 12 U1 0 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-022X J9 J BIOCHEM BIOPH METH JI J. Biochem. Biophys. Methods PD MAY PY 1993 VL 26 IS 2-3 BP 121 EP 129 DI 10.1016/0165-022X(93)90042-M PG 9 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA KY854 UT WOS:A1993KY85400004 PM 8509600 ER PT J AU HIGHSMITH, S KUBINEC, M JAISWAL, DK MORIMOTO, H WILLIAMS, PG WEMMER, DE AF HIGHSMITH, S KUBINEC, M JAISWAL, DK MORIMOTO, H WILLIAMS, PG WEMMER, DE TI [2-H-3]ATP SYNTHESIS AND H-3 NMR-SPECTROSCOPY OF ENZYME-NUCLEOTIDE COMPLEXES - ADP AND ADP.VI BOUND TO MYOSIN SUBFRAGMENT-1 SO JOURNAL OF BIOMOLECULAR NMR LA English DT Article DE TRITIUM NMR; ATP; MYOSIN; ATP SITE; VANADATE ID NUCLEAR MAGNETIC-RESONANCE; HEAVY-CHAIN; ACTIN; BINDING; MUSCLE; SITE; SKELETAL; ATPASE; TRYPTOPHAN-130; TRIPHOSPHATE AB The synthesis of [2-H-3]ATP with specific activity high enough to use for H-3 NMR spectroscopy at micromolar concentrations was accomplished by tritiodehalogenation of 2-Br-ATP. ATP with greater than 80% substitution at the 2-position and negligible tritium levels at other positions had a single H-3 NMR peak at 8.20 ppm in ID spectra obtained at 533 MHz. This result enables the application of tritium NMR spectroscopy to ATP utilizing enzymes. The proteolytic fragment of skeletal muscle myosin, called S1, consists of a heavy chain (95 kDa) and one alkali light chain (16 or 21 kDa) complex that retains myosin ATPase activity. In the presence of Mg2+, S1 converts [2-H-3]ATP to [2-H-3]ADP and the complex S1.Mg[2-H-3]ADP has ADP bound in the active site. At 0-degrees-C, 1D H-3 NMR spectra of S1.Mg[2-H-3]ADP have two broadened peaks shifted 0.55 and 0.90 ppm upfield from the peak due to free [2-H-3]ADP. Spectra with good signal-to-noise for 0.10 mM S1.Mg[2-H-3]ADP were obtained in 180 min. The magnitude of the chemical shift caused by binding is consistent with the presence of an aromatic side chain being in the active site. Spectra were the same for S1 with either of the alkali light chains present, suggesting that the alkali light chains do not interact differently with the active site. The two broad peaks appear to be due to the two conformations of S1 that have been observed previously by other techniques. Raising the temperature to 20-degrees-C causes small changes in the chemical shifts, narrows the peak widths from 150 to 80 Hz, and increases the relative area under the more upfield peak. Addition of orthovanadate (V(i)) to produce S1.Mg[2-H-3]ADP.V(i) shifts both peaks slightly more upfield without changing their widths or relative areas. C1 LAWRENCE BERKELEY LAB,NATL TRITIUM LABELING FACIL,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV STRUCT BIOL,BERKELEY,CA 94720. RP HIGHSMITH, S (reprint author), UNIV PACIFIC,DEPT BIOCHEM,SAN FRANCISCO,CA 94115, USA. FU NCRR NIH HHS [P41 RR01237]; NIAMS NIH HHS [AR37499] NR 40 TC 8 Z9 8 U1 1 U2 1 PU ESCOM SCI PUBL BV PI LEIDEN PA PO BOX 214, 2300 AE LEIDEN, NETHERLANDS SN 0925-2738 J9 J BIOMOL NMR JI J. Biomol. NMR PD MAY PY 1993 VL 3 IS 3 BP 325 EP 334 DI 10.1007/BF00212518 PG 10 WC Biochemistry & Molecular Biology; Spectroscopy SC Biochemistry & Molecular Biology; Spectroscopy GA LE201 UT WOS:A1993LE20100007 PM 8358234 ER PT J AU SEARS, TJ RADFORD, HE MOORE, MA AF SEARS, TJ RADFORD, HE MOORE, MA TI B-DIPOLE TRANSITIONS IN TRANS-HOCO OBSERVED BY FAR-INFRARED LASER MAGNETIC-RESONANCE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID OH + CO; GROUND-STATE; SPECTRUM; HO2; HCO AB Far infrared laser magnetic resonance spectroscopy is used to measure components of 12 rotational transitions in the ground state of the HOCO radical. The transitions are all b-dipole in character in contrast to the a-dipole rotational spectrum previously reported [Radford, Wei, and Sears, J. Chem. Phys. 97, 3989 (1992)]. The new data determine the A rotational constant to high precision and allow the determination of several centrifugal distortion constants for the first time. The hyperfine coupling in the radical leads to observable splittings in several of the observed transitions and these are used to estimate two of the four expected nonzero hyperfine parameters in the radical. C1 HARVARD SMITHSONIAN CTR ASTROPHYS, CAMBRIDGE, MA 02138 USA. RP SEARS, TJ (reprint author), BROOKHAVEN NATL LAB, DEPT CHEM, UPTON, NY 11973 USA. RI Sears, Trevor/B-5990-2013 OI Sears, Trevor/0000-0002-5559-0154 NR 24 TC 43 Z9 43 U1 1 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 MAY 1 PY 1993 VL 98 IS 9 BP 6624 EP 6631 DI 10.1063/1.465098 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LA763 UT WOS:A1993LA76300004 ER PT J AU PARKER, GA PACK, RT AF PARKER, GA PACK, RT TI QUANTUM REACTIVE SCATTERING IN 3 DIMENSIONS USING HYPERSPHERICAL (APH) COORDINATES .6. ANALYTIC BASIS METHOD FOR SURFACE FUNCTIONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POTENTIAL-ENERGY SURFACE; INTEGRAL CROSS-SECTIONS; PHOTODETACHMENT SPECTRUM; REACTION HE+H2+->HEH++H; REACTION PROBABILITIES; LANCZOS METHOD; F+H2->HF+H; REPRESENTATION; F+H-2->HF+H; RESONANCES AB We continue development of the theory of reactive (rearrangement) scattering using adiabatically adjusting principal axes hyperspherical (APH) coordinates. The surface functions, functions of the APH hyperangles covering the surface of the internal coordinate sphere, are expanded in analytic basis functions centered in each of the arrangement channels. The rotational functions are associated Legendre polynomials, and the vibrational functions are harmonic functions of an ''anharmonic'' variable which covers an infinite range, allows accurate Gauss-Hermite quadrature, and includes effects of anharmonicity. Example calculations show that these functions provide an efficient basis which can markedly decrease the computational effort required to generate accurate surface functions. C1 LOS ALAMOS NATL LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. RP UNIV OKLAHOMA, DEPT PHYS & ASTRON, NORMAN, OK 73019 USA. RI Parker, Gregory/A-4327-2009 OI Parker, Gregory/0000-0002-0225-8887 NR 61 TC 50 Z9 50 U1 0 U2 1 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 MAY 1 PY 1993 VL 98 IS 9 BP 6883 EP 6896 DI 10.1063/1.464778 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LA763 UT WOS:A1993LA76300029 ER PT J AU AUERBACH, SM MILLER, WH AF AUERBACH, SM MILLER, WH TI QUANTUM-MECHANICAL REACTION PROBABILITIES WITH A POWER-SERIES GREEN-FUNCTION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Review ID DEPENDENT SCHRODINGER-EQUATION; TRANSITION-STATE THEORY; KOHN VARIATIONAL PRINCIPLE; THERMAL RATE CONSTANTS; PATH INTEGRAL METHODS; DISCRETE VARIABLE REPRESENTATIONS; MICROCANONICAL RATE CONSTANTS; POTENTIAL-ENERGY SURFACE; LANCZOS VECTOR-SPACE; WAVE PACKET DYNAMICS AB We present a new method to compute the energy Green's function with absorbing boundary conditions for use in the calculation of quantum mechanical reaction probabilities. This is an iterative technique to compute the inverse of a complex matrix which is based on Fourier transforming time-dependent dynamics. The Hamiltonian is evaluated in a sinc-function based discrete variable representation, which we argue may often be superior to the fast Fourier transform method for reactive scattering. We apply the resulting power series Green's function to the calculation of the cumulative reaction probability for the benchmark collinear H+H-2 system over the energy range 0.37-1.27 eV. The convergence of the power series is found to be stable at all energies and accelerated by the use of a stronger absorbing potential. C1 LAWRENCE BERKELEY LAB, DIV CHEM SCI, BERKELEY, CA 94720 USA. RP AUERBACH, SM (reprint author), LAWRENCE BERKELEY LAB, DEPT CHEM, BERKELEY, CA 94720 USA. RI Garcia-Sanchez, Almudena/B-3303-2009 NR 131 TC 18 Z9 18 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1993 VL 98 IS 9 BP 6917 EP 6928 DI 10.1063/1.464759 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LA763 UT WOS:A1993LA76300032 ER PT J AU MCRAE, RP GARRETT, BC AF MCRAE, RP GARRETT, BC TI ANHARMONIC CORRECTIONS TO VARIATIONAL TRANSITION-STATE THEORY CALCULATIONS OF RATE CONSTANTS FOR A MODEL ACTIVATED REACTION IN SOLUTION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PATH INTEGRAL APPROACH; MOLECULAR-DYNAMICS; WATER; APPROXIMATION; SYSTEMS AB Previous errors in harmonic variational transition state theory calculations of rate constants for a model of an activated reaction in solution are corrected by including anharmonicities in the calculations of bound state energy levels. Harmonic variational transition state theory including multidimensional quantum mechanical corrections for reaction coordinate motion has previously been used to calculate the rate constant for a reaction model corresponding to a single solute coordinate coupled to a harmonic bath. Comparison of these rate constants with accurate quantum mechanical rate constants showed good agreement, in general, with the worst discrepancy to be a factor of 3.6. By including anharmonicities in the bound vibrational potentials to infinite order and calculating the energy levels by a uniform semiclassical prescription, the maximum error is reduced to 42%. C1 PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. RI Garrett, Bruce/F-8516-2011 NR 48 TC 11 Z9 11 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1993 VL 98 IS 9 BP 6929 EP 6934 DI 10.1063/1.464760 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LA763 UT WOS:A1993LA76300033 ER PT J AU KRESIN, VV SCHEIDEMANN, A AF KRESIN, VV SCHEIDEMANN, A TI SCATTERING OF NEUTRAL METAL-CLUSTERS - LONG-RANGE INTERACTIONS AND RESPONSE PROPERTIES SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CHARGE-EXCHANGE AB The absolute integral cross sections for low-energy collisions of neutral sodium clusters Na(n) (n=2-40) with atoms and molecules (Ar, N2, O2, and halogens) have been measured. The cross sections are found to be exceptionally large (up to thousands of square angstroms), showing the dominant role of long-range intermolecular interactions. Elastic scattering proceeding under the influence of the van der Waals force, and a reaction channel involving electron transfer can successfully describe the measurements. The strength of the van der Waals potential is defined by such cluster response properties as the electric polarizability and the frequency of the giant dipole resonance. The reactive electron-jump channel, in turn, is described by the ''harpooning'' mechanism which is sensitive to the cluster ionization potential. Employing parameters taken from spectroscopic studies of alkali clusters, we obtain good agreement with the observed cross sections. This provides a direct connection between beam scattering experiments and studies of cluster electromagnetic response properties. C1 UNIV WASHINGTON,DEPT CHEM,SEATTLE,WA 98195. RP KRESIN, VV (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. RI Kresin, Vitaly/N-8095-2014 OI Kresin, Vitaly/0000-0002-6226-4576 NR 44 TC 25 Z9 25 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1993 VL 98 IS 9 BP 6982 EP 6988 DI 10.1063/1.464740 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LA763 UT WOS:A1993LA76300039 ER PT J AU FELLER, D AF FELLER, D TI THE USE OF SYSTEMATIC SEQUENCES OF WAVE-FUNCTIONS FOR ESTIMATING THE COMPLETE BASIS SET, FULL CONFIGURATION-INTERACTION LIMIT IN WATER SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HARTREE-FOCK LIMIT; ONE-ELECTRON PROPERTIES; MOLECULAR-PROPERTIES; MODEL CHEMISTRY; PERTURBATION-THEORY; TOTAL ENERGIES; DIPOLE-MOMENT; GROUND-STATE; SCF; H2O AB An assortment of 1- and 2-electron water properties were extracted from a systematic sequence of wave functions. The regularity inherent in this sequence permitted simple exponential fits of the resulting energies and, in many cases, the properties. To the extent the exponential fit accurately reflects the asymptotic convergence of a specific property, it provides an estimate of the complete basis set, full configuration interaction (CI) limiting value at a reduced computational expense. As a consequence of the vast reduction in the number of configurations that must be treated variationally, the proposed scheme may make possible improved estimates of the complete basis set, full CI limit beyond what could be obtained from explicit computations. In order to judge the accuracy of the procedure, we have carried out the highest level ab initio calculations to date on water, recovering in excess of 96% of the estimated valence correlation energy. RP FELLER, D (reprint author), PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. NR 50 TC 429 Z9 430 U1 2 U2 24 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 MAY 1 PY 1993 VL 98 IS 9 BP 7059 EP 7071 DI 10.1063/1.464749 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LA763 UT WOS:A1993LA76300048 PM 16468851 ER PT J AU BOYLE, JS AF BOYLE, JS TI SENSITIVITY OF DYNAMIC QUANTITIES TO HORIZONTAL RESOLUTION FOR A CLIMATE SIMULATION USING THE ECMWF (CYCLE-33) MODEL SO JOURNAL OF CLIMATE LA English DT Article ID GENERAL-CIRCULATION; FORECAST SKILL; PARAMETRIZATION; PREDICTION AB The European Centre for Medium-Range Weather Forecasts (ECMWF) model (cycle 33) was integrated for a full seasonal cycle at four horizontal resolutions, T21, T42, T63, and T106. Within the limits imposed by the varying horizontal resolution all other aspects of the model were identical for each integration. In this paper a comparison is made of the dynamical aspects of the simulations. Fields of zonally averaged zonal wind, eddy heat and momentum fluxes, global divergent wind and vorticity, and stationary wave patterns are presented and compared for each resolution. The conclusions reached by this study are (i) T21 is qualitatively different from the higher resolutions; (ii) the highest resolution does not provide a simulation that is egregiously superior to T42. There are aspects of the T21 simulation, especially in tropical convection, that are clearly better than the higher resolutions; (iii) aside from differences in smaller-scale boundary forcing at the higher resolutions, the T42, T63, T106 simulations are nearly identical in the dynamical aspects of the circulation considered here; and (iv) increasing horizontal resolution alone will not result in an overall superior simulation, unless other aspects of the model are modified at an equal pace. RP BOYLE, JS (reprint author), LAWRENCE LIVERMORE NATL LAB,PROGRAM CLIMATE MODEL DIAG & INTERCOMPARISON,G DIV L264,LIVERMORE,CA 94551, USA. NR 23 TC 64 Z9 69 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 MAY PY 1993 VL 6 IS 5 BP 796 EP 815 DI 10.1175/1520-0442(1993)006<0796:SODQTH>2.0.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA LC409 UT WOS:A1993LC40900002 ER PT J AU SABOURIN, CLK KUSEWITT, DF FRY, RJM LEY, RD AF SABOURIN, CLK KUSEWITT, DF FRY, RJM LEY, RD TI ULTRAVIOLET RADIATION-INDUCED CORNEAL TUMORS IN THE SOUTH-AMERICAN OPOSSUM, MONODELPHIS-DOMESTICA SO JOURNAL OF COMPARATIVE PATHOLOGY LA English DT Article ID MALIGNANT FIBROUS HISTIOCYTOMA; INDUCED SKIN TUMORS; INTERMEDIATE FILAMENTS; TRANSGENIC MICE; SEQUENCE; LIMBUS; GENOME C1 OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. RP SABOURIN, CLK (reprint author), LOVELACE FDN MED EDUC & RES,CTR BASIC & APPL MED RES,CTR PHOTOMED,2425 RIDGECREST DR SE,ALBUQUERQUE,NM 87108, USA. RI Kusewitt, Donna/E-8107-2011 FU NIEHS NIH HHS [1-RO1-ES05180] NR 38 TC 17 Z9 17 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0021-9975 J9 J COMP PATHOL JI J. Comp. Pathol. PD MAY PY 1993 VL 108 IS 4 BP 343 EP 359 DI 10.1016/S0021-9975(08)80206-X PG 17 WC Pathology; Veterinary Sciences SC Pathology; Veterinary Sciences GA LJ218 UT WOS:A1993LJ21800003 PM 8366202 ER PT J AU BASS, MB ORNSTEIN, RL AF BASS, MB ORNSTEIN, RL TI SUBSTRATE-SPECIFICITY OF CYTOCHROME-P450CAM FOR L-NORCAMPHOR AND D-NORCAMPHOR AS STUDIED BY MOLECULAR-DYNAMICS SIMULATIONS SO JOURNAL OF COMPUTATIONAL CHEMISTRY LA English DT Article ID AMINO-ACID; PROTEIN; CYTOCHROME-P-450CAM; CAMPHOR; HYDROXYLATION; PARAMETERS; P-450CAM; MUTATION; MODELS AB In our earlier molecular dynamics simulations, we found that there was a discrepancy between the predicted and experimental product ratios when norcamphor is hydroxylated by cytochrome P450cam. The experimental results suggest that there is a nearly equimolar ratio between the 5- and 6-hydroxynorcamphor (45% 5-, 47% 6-, and 8% 3-hydroxynorcamphor) [W.M. Atkins and S.J. Sligar, J. Am. Chem. Soc., 109, 3754 (1987)]. Our previous simulations predicted predominately from 68-88%) 5-hydroxynorcamphor [M.B. Bass et al., Prot. Struct. Funct Genet., 13, 26 (1992); M.B. Bass et al., Proc. Natl. Acad. Sci. U.S.A., submitted]. One possible explanation for this discrepancy is that the simulations were performed using D-norcamphor while the experiments were conducted with racemic norcamphor. The suggestion that norcamphor is the D-isomer was based upon the similarity with the native substrate D-camphor. Indeed, the reported crystallographic structure for norcamphor-bound P450cam models norcamphor as the D-isomer. Unfortunately, the two stereomers have never been separated. The simulations presented here model the L-isomer of norcamphor. Three simulations each of the L- and D-isomers of norcamphor bound to cytochrome P450cam were compared to account for the effects due to substrate orientation and the assignment of random velocities. The results presented here show that the L-isomer of norcamphor is predicted to give rise to predominately 6-hydroxynorcamphor, while the D-isomer gives rise to mainly 5-hydroxynorcamphor. From this data, we infer that racemic norcamphor will give rise to nonracemic 5- and 6-hydroxynorcamphors after oxidation by cytochrome P450cam. C1 PACIFIC NW LAB, ENVIRONM SCI RES CTR, RICHLAND, WA 99352 USA. PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. NR 41 TC 7 Z9 7 U1 1 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0192-8651 J9 J COMPUT CHEM JI J. Comput. Chem. PD MAY PY 1993 VL 14 IS 5 BP 541 EP 548 DI 10.1002/jcc.540140506 PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA KX328 UT WOS:A1993KX32800005 ER PT J AU NGUYEN, HD PAIK, S CHUNG, JN AF NGUYEN, HD PAIK, S CHUNG, JN TI APPLICATION OF VORTICITY INTEGRAL CONDITIONING TO CHEBYSHEV PSEUDOSPECTRAL FORMULATION FOR THE NAVIER-STOKES EQUATIONS SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID INCOMPRESSIBLE FLOWS C1 WASHINGTON STATE UNIV,DEPT MECH & MAT ENGN,PULLMAN,WA 99164. RP NGUYEN, HD (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415, USA. NR 15 TC 6 Z9 6 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAY PY 1993 VL 106 IS 1 BP 115 EP 124 DI 10.1006/jcph.1993.1096 PG 10 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA KY460 UT WOS:A1993KY46000011 ER PT J AU CARSON, CC HUELSKAMP, RM WOODALL, TD AF CARSON, CC HUELSKAMP, RM WOODALL, TD TI PERSPECTIVES ON EDUCATION IN AMERICA - AN ANNOTATED BRIEFING SO JOURNAL OF EDUCATIONAL RESEARCH LA English DT Article AB Sandia National Laboratories has been involved in education throughout much of its existence. Historically, the thrust of this involvement has been at the postsecondary level. At the behest of Admiral James Watkins, Secretary of Energy, Sandia is expanding its efforts with a greater focus on elementary and secondary education. The purpose of this study, conducted by the New Initiatives Department for the Strategic Studies Center, is to provide a foundation for Sandia's future activities in education. The study includes detailed analyses of dropout statistics, standardized tests, postsecondary studies, educational funding, international comparisons, and educator status. It also addresses future workforce requirements, the changing student demographics, and the education goals proposed by President Bush and the nation's Governors. RP CARSON, CC (reprint author), SANDIA NATL LABS,CTR STRATEG STUDIES,ALBUQUERQUE,NM 87185, USA. NR 0 TC 19 Z9 19 U1 0 U2 1 PU HELDREF PUBLICATIONS PI WASHINGTON PA 1319 EIGHTEENTH ST NW, WASHINGTON, DC 20036-1802 SN 0022-0671 J9 J EDUC RES JI J. Educ. Res. PD MAY-JUN PY 1993 VL 86 IS 5 BP 259 EP & PG 0 WC Education & Educational Research SC Education & Educational Research GA LJ862 UT WOS:A1993LJ86200001 ER PT J AU WULLSCHLEGER, SD AF WULLSCHLEGER, SD TI BIOCHEMICAL LIMITATIONS TO CARBON ASSIMILATION IN C(3) PLANTS - A RETROSPECTIVE ANALYSIS OF THE A/CI CURVES FROM 109 SPECIES SO JOURNAL OF EXPERIMENTAL BOTANY LA English DT Review DE A/CI CURVE; CO2 ASSIMILATION; INTERNAL CO2 PARTIAL PRESSURE; PHOTOSYNTHESIS ID PHASEOLUS-VULGARIS L; GAS-EXCHANGE CHARACTERISTICS; BISPHOSPHATE CARBOXYLASE ACTIVITY; SIEB-EX-SPRENG; CO2 ASSIMILATION; PHOTOSYNTHETIC CHARACTERISTICS; STOMATAL CONDUCTANCE; EUCALYPTUS-PAUCIFLORA; ABSCISIC-ACID; STEADY-STATE AB Species-specific differences in the assimilation of atmospheric CO2 depends upon differences in the capacities for the biochemical reactions that regulate the gas-exchange process. Quantifying these differences for more than a few species, however, has proven difficult. Therefore, to understand better how species differ in their capacity for CO2 assimilation, a widely used model, capable of partitioning limitations to the activity of ribulose-1,5-bisphosphate carboxylase-oxygenase, to the rate of ribulose 1,5-bisphosphate regeneration-via electron transport, and to the rate of triose phosphate utilization was used to analyse 164 previously published A/C(i) curves for 109 C3 plant species. Based on this analysis, the maximum rate of carboxylation, Vc(max), ranged from 6 mumol m-2 s-1 for the coniferous species Picea abies to 194 mumol m-2 s-1 for the agricultural species Beta vulgaris, and averaged 64 mumol m-2 s-1 across all species. The maximum rate of electron transport, J(max), ranged from 17 mumol m-2 s-1 again for Picea abies to 372 mumol m-2 s-1 for the desert annual Malvastrum rotundifolium, and averaged 134 mumol m-2 s-1 across all species. A strong positive correlation between V(max) and J(max) indicated that the assimilation Of CO2 was regulated in a co-ordinated manner by these two component processes. Of the A/C(i) curves analysed, 23 showed either an insensitivity or reversed-sensitivity to increasing CO2 concentration, indicating that CO2 assimilation was limited by the utilization of triose phosphates. The rate of triose phosphate utilization ranged from 4.9 mumol m-2 s-1 for the tropical perennial Tabebuia rosea to 20.1 muMol m-2 s-1 for the weedy annual Xanthium strumarium, and averaged 10.1 muMol M-2 s-1 across all species. Despite what at first glance would appear to be a wide range of estimates for the biochemical capacities that regulate CO2 assimilation, separating these species-specific results into those of broad plant categories revealed that Vc(max) and J(max) were in general higher for herbaceous annuals than they were for woody perennials. For annuals, Vc(max) and J(max) averaged 75 and 154 muMol M-2 S-1, While for perennials these same two parameters averaged only 44 and 97 mumol M-2s-1, respectively. Although these differences between groups may be coincidental, such an observation points to differences between annuals and perennials in either the availability or allocation of resources to the gas-exchange process. RP WULLSCHLEGER, SD (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,OAK RIDGE,TN 37831, USA. RI Wullschleger, Stan/B-8297-2012; Kodama, Naomi/D-9553-2011 OI Wullschleger, Stan/0000-0002-9869-0446; Kodama, Naomi/0000-0001-9913-9886 NR 144 TC 631 Z9 661 U1 23 U2 125 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0022-0957 J9 J EXP BOT JI J. Exp. Bot. PD MAY PY 1993 VL 44 IS 262 BP 907 EP 920 DI 10.1093/jxb/44.5.907 PG 14 WC Plant Sciences SC Plant Sciences GA LD454 UT WOS:A1993LD45400008 ER PT J AU BRINCA, AL DEAGUA, LB WINSKE, D AF BRINCA, AL DEAGUA, LB WINSKE, D TI ON THE STABILITY OF NONGYROTROPIC ION POPULATIONS - A 1ST (ANALYTIC AND SIMULATION) ASSESSMENT SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID PERPENDICULAR BOW SHOCK; REFLECTED IONS; GYRATING IONS; UPSTREAM; DISTRIBUTIONS; BETA AB The wave and dispersion equations for perturbations propagating parallel to an ambient magnetic field in magnetoplasmas with nongyrotropic ion populations show, in general, the occurrence of coupling between the parallel (left- and right-hand circularly polarized electromagnetic and longitudinal electrostatic) eigenmodes of the associated gyrotropic medium. These interactions provide a means to driving linearly one mode with free-energy sources of other modes in homogeneous media. Different types of nongyrotropy bring about distinct classes of coupling. The stability of a hydrogen magnetoplasma with anisotropic, nongyrotropic protons that only couple the electromagnetic modes to each other is investigated analytically (via solution of the derived dispersion equation) and numerically (via simulation with a hybrid code). Nongyrotropy enhances growth and enlarges the unstable spectral range relative to the corresponding gyrotropic situation. The relevance of the properties of nongyrotropic populations to space plasma environments is also discussed. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. RP BRINCA, AL (reprint author), Univ Tecn Lisboa, INST SUPER TECN, CTR ELECTRODINAM, P-1096 LISBON, PORTUGAL. RI Borda-de-Agua, Luis/D-6063-2011 OI Borda-de-Agua, Luis/0000-0002-0802-6235 NR 20 TC 25 Z9 25 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1993 VL 98 IS A5 BP 7549 EP 7560 DI 10.1029/92JA01874 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LB643 UT WOS:A1993LB64300004 ER PT J AU RASSOUL, HK ROHRBAUGH, RP TINSLEY, BA SLATER, DW AF RASSOUL, HK ROHRBAUGH, RP TINSLEY, BA SLATER, DW TI SPECTROMETRIC AND PHOTOMETRIC-OBSERVATIONS OF LOW-LATITUDE AURORAE SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INCIDENT ELECTRON-SPECTRA; SAR ARC FORMATION; RED ARCS; DEDUCING COMPOSITION; OPTICAL MEASUREMENTS; CROSS-SECTIONS; RING CURRENT; PRECIPITATION; EXCITATION; EMISSIONS AB The properties of a low-latitude aurora of September 22, 1982, observed with photometers and a spectrograph from McDonald Observatory, Texas, and an all-sky mapping photometer from a site near Boulder, Colorado, are discussed. The dominant emission was [OI] 630 nm with a 630/558 nm emission ratio of 3.8. Other weaker emissions were present that are characteristic of heavy particle aurorae and can be attributed to energetic (keV) ions and neutral atoms from the ring current. The properties of this and other low-latitude aurorae are discussed in the context of stable auroral red (SAR) arcs and type d aurorac, and of energetic ion and neutral aurorae. The emissions associated wi th heavy particle precipitation are characteristic of main phase conditions. The observed equatorial movement of main phase low-latitude red aurorae is consistent with the inward convection of ring current particles and the inward movement of the plasmapause. Previous work has hypothesized that coulomb collisions of plasmaspheric electrons with ring current O+ cause the energization of the electrons exciting SAR arcs. Calculations of [OI] 630 and 558 nm emissions show that for red aurorae with 630/558 nm ratios approximately 4, additional energization processes producing electrons in the energy range 10-10,000 eV are required. We propose some clarification of nomenclature for several types of aurorae occurring at low latitudes. C1 UNIV TEXAS, CTR SPACE SCI, RICHARDSON, TX 75083 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. RP RASSOUL, HK (reprint author), FLORIDA INST TECHNOL, DEPT PHYS & SPACE SCI, 150 W UNIV BLVD, MELBOURNE, FL 32901 USA. NR 67 TC 31 Z9 32 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 MAY 1 PY 1993 VL 98 IS A5 BP 7695 EP 7709 DI 10.1029/92JA02269 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LB643 UT WOS:A1993LB64300017 ER PT J AU RAO, MN GARRISON, DH BOGARD, DD REEDY, RC AF RAO, MN GARRISON, DH BOGARD, DD REEDY, RC TI SOLAR-FLARE-IMPLANTED HE-4 HE-3 AND SOLAR-PROTON-PRODUCED NE AND AR CONCENTRATION PROFILES PRESERVED IN LUNAR ROCK 61016 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CROSS-SECTIONS; NOBLE-GASES; ISOTOPIC COMPOSITION; EXPOSURE AGES; METEORITES; PARTICLES; HELIUM; NUCLEI; ABUNDANCES; SOIL AB Documented near-surface samples from oriented lunar rock 61016 have yielded the first measurements of depth profiles for Ne-21, Ne-22, and Ar-38 isotopes produced in situ from nuclear interactions of energetic solar flare protons. Further, the cosmogenic Ne-21/Ne-22 ratios are distinct for different proton energy ranges and increase systematically with increasing shielding. This variation in cosmogenic Ne-21/Ne-22 represents a progression from a mixed component produced from solar flare protons (SCR) and galactic cosmic rays (GCR) to a pure GCR component. Using the 2 m.y. exposure age for 61016, the calculated production rates for SCR Ne-21 and Ar-38 from solar energetic protons in near-surface samples agree within 5% and 25%, respectively, with theoretical estimates. Calculated GCR production rates for Ne-21 and Ar-22 in the deepest (26 mm) samples agree within 25% and 10%, respectively, with theoretical estimates. Combined SCR and GCR concentration profiles for Ne-21/Ne-22, and Ar-38 match theoretical calculations based on an omnidirectional flux above 10 MeV of 100 protons cm-2 s-1 with an exponential rigidity between 70 and 85 MV and a surface erosion rate of 1 mm m.y.-1. Selectively etched, near-surface samples suggest a long-term average He-4/He-3 ratio of approximately 770 for implanted solar flare nuclei with E > approximately 4 MeV amu-1, and a He-4/He-3 ratio of approximately 3450 for solar flare nuclei with E > -1 McV amu-1. Averaged over long term, the solar flare He-4/He-3 ratio appears energy dependent. C1 NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058. LOCKHEED ENGN & SCI CO,HOUSTON,TX 77258. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP RAO, MN (reprint author), LUNAR & PLANETARY INST,3600 BAY AREA BLVD,HOUSTON,TX 77058, USA. NR 39 TC 9 Z9 9 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1993 VL 98 IS A5 BP 7827 EP 7835 DI 10.1029/93JA00002 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LB643 UT WOS:A1993LB64300029 ER PT J AU UNAL, A CHYU, MC KUZAY, TM AF UNAL, A CHYU, MC KUZAY, TM TI STABILITY AND RECOVERY BEHAVIOR OF TAPE FILM-TYPE SUPERCONDUCTORS SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Note DE CONDUCTION; TRANSIENT AND UNSTEADY HEAT TRANSFER C1 ARGONNE NATL LAB, DIV MAT & COMPONENTS TECHNOL, ARGONNE, IL 60439 USA. RP TEXAS TECH UNIV, DEPT MECH ENGN, LUBBOCK, TX 79409 USA. RI Makina, KTU/K-7182-2012 OI Makina, KTU/0000-0003-0130-0876 NR 7 TC 5 Z9 5 U1 0 U2 2 PU ASME PI NEW YORK PA TWO PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 EI 1528-8943 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD MAY PY 1993 VL 115 IS 2 BP 467 EP 469 PG 3 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA LE445 UT WOS:A1993LE44500024 ER PT J AU TUNG, VX DHIR, VK AF TUNG, VX DHIR, VK TI CONVECTIVE HEAT-TRANSFER FROM A SPHERE EMBEDDED IN UNHEATED POROUS-MEDIA SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Note DE FORCED CONVECTION; GEOPHYSICAL HEAT TRANSFER; POROUS MEDIA ID THERMAL-CONDUCTIVITY; BEDS C1 UNIV CALIF LOS ANGELES,SCH ENGN & APPL SCI,DEPT MECH AEROSP & NUCL ENGN,LOS ANGELES,CA 90024. RP TUNG, VX (reprint author), EG&G IDAHO INC,IDAMO NATL ENGN LAB,IDAHO FALLS,ID 83415, USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD MAY PY 1993 VL 115 IS 2 BP 503 EP 506 DI 10.1115/1.2910713 PG 4 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA LE445 UT WOS:A1993LE44500036 ER PT J AU WILSON, GV JARDINE, PM ODELL, JD COLLINEAU, M AF WILSON, GV JARDINE, PM ODELL, JD COLLINEAU, M TI FIELD-SCALE TRANSPORT FROM A BURIED LINE SOURCE IN VARIABLY SATURATED SOIL SO JOURNAL OF HYDROLOGY LA English DT Article ID CONTROLLING SUBSURFACE TRANSPORT; HUMID HEADWATER CATCHMENTS; STORM RUNOFF GENERATION; 2 FORESTED WATERSHEDS; SOLUTE TRANSPORT; UPPER SUBCATCHMENT; UNSATURATED SOIL; FLOW PREDICTIONS; EVENTS; MACROPOROSITY AB Lateral subsurface flow through the upper soil layers (stormflow zone) during storm events has been shown to be a dominant mechanism of contaminant transport in forested watersheds. Data bases for multi-region flow and transport modeling for hydrogeologic conditions where stormflow predominates are lacking. Direct measurement of the tracer flux under field-scale conditions are non-existent. The objective of this paper was to evaluate the significance of three hydrologic pore regions to stormflow. Two tracer releases were made from a buried line source during storm events and the spatial and temporal variability in solute concentration and the tracer fluxes were measured. During one of the injections, macropore flow was extremely rapid with solute transport to a downslope trench 65 m from the line source taking just 3.2 h. Mesopore flow appeared to be significant for short distances in that tracer movement to solution samplers just 3 m downslope of the line source occurred within 3 h of the release. Soil sampling 6 months after the second release revealed that the tracer plume was refracted in the direction of the fractured bedding plane, and therefore did not coincide with the array of samplers for distances greater than 13 m downslope of the source. Soil sampling data suggested that micropores served as a sink/source for Br- with 47% of the non-reactive tracer remaining immobilized by micropores at the termination of the study. Interaction between the upper 2 m of the stormflow zone and the groundwater system was believed minimal: however, lateral flow below 2 m was concluded to be significant. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP WILSON, GV (reprint author), UNIV TENNESSEE,DEPT PLANT & SOIL SCI,POB 1071,KNOXVILLE,TN 37901, USA. NR 32 TC 53 Z9 53 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD MAY 1 PY 1993 VL 145 IS 1-2 BP 83 EP 109 DI 10.1016/0022-1694(93)90221-T PG 27 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA KY539 UT WOS:A1993KY53900005 ER PT J AU BANCI, L CABELLI, DE GETZOFF, ED HALLEWELL, RA VIEZZOLI, MS AF BANCI, L CABELLI, DE GETZOFF, ED HALLEWELL, RA VIEZZOLI, MS TI AN ESSENTIAL ROLE FOR THE CONSERVED GLU-133 IN THE ANION INTERACTION WITH SUPEROXIDE-DISMUTASE SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Article ID ACTIVE-SITE; COPPER; MECHANISM; BINDING; DERIVATIVES; CU2CO2SOD; RADICALS; MUTANTS; ENZYME; RADIOLYSIS AB Negatively charged glutamic acid residues at positions 132 and 133 in human Cu2Zn2SOD are located at the entrance to the active site cavity and affect electrostatic interactions with the negatively charged substrate. The mutants in which these residues have been neutralized separately and together by conversion to glutamine residues or changed to a positive group on position 133 have been characterized through a variety of biophysical techniques. The structure around the metal ions, as monitored by spectroscopic measurements, is the same in the mutants and native enzyme. The mutants have been characterized with respect to the affinity for the anion N3-. The mutants have larger affinity for azide than the WT, as a result of the removal of one or two negative charges or of the introduction of a positive group. The pattern of the azide affinity constants parallels that of the rate of O2- dismutation. The substitution of the negative Glu-133 with a positive group does not induce a larger increase in the affinity as well as in the catalytic rates with respect to its neutralization. These patterns cannot, therefore, be rationalized only in terms of electrostatic interactions. The behavior of the mutants towards the substrate (O2-) and substrate analogue (N3-) is discussed on the basis of theoretical predictions available in the literature. C1 BROOKHAVEN NATL LAB, DEPT CHEM, UPTON, NY 11973 USA. CHIRON CORP, EMERYVILLE, CA USA. SCRIPPS RES INST, DEPT MOLEC BIOL, LA JOLLA, CA USA. RP BANCI, L (reprint author), UNIV FLORENCE, DEPT CHEM, VIA G CAPPONI 7, I-50121 FLORENCE, ITALY. FU NIGMS NIH HHS [GM 39345] NR 51 TC 17 Z9 17 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD MAY 1 PY 1993 VL 50 IS 2 BP 89 EP 100 DI 10.1016/0162-0134(93)80016-3 PG 12 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA KV512 UT WOS:A1993KV51200002 PM 8098056 ER PT J AU BENSON, SM DELAMORE, M HOFFMAN, S AF BENSON, SM DELAMORE, M HOFFMAN, S TI KESTERSON CRISIS SO JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING-ASCE LA English DT Article; Proceedings Paper CT NATIONAL CONF ON IRRIGATION AND DRAINAGE CY JUL 11-13, 1990 CL DURANGO, CO SP AMER SOC CIVIL ENGINEERS ID GROUNDWATER CONTAMINATION; IRRIGATION DRAINWATER; CALIFORNIA; SELENIUM; RESERVOIR AB The events leading to selenium contamination at the Kesterson Reservoir, a man-made marsh in the Central Valley of California, began in the early 1900s, with the diversion of water to irrigate saline soils containing naturally high concentrations of selenium. With the advent of a systematic plan to collect and dispose of subsurface drainage water from these lands, problems associated with concentration and biological cycling of selenium became apparent at Kesterson, a series of shallow-drainage-water disposal ponds that was also managed as a wetland habitat. When chicks of hundreds of shorebirds failed to survive and deformed embryos were discovered. the California State Water Resources Control Board initiated a series of regulatory proceedings. This led to the closure of the Kesterson Reservoir and a series of remedial measures which went through numerous iterations as a team of scientists provided a more thorough understanding of processes leading to selenium transport and biologic exposure in this environment. In particular, field experiments and intensive monitoring demonstrated three factors leading to a cost-effective resolution of the Kesterson cleanup. First. ground water under Kesterson was protected from selenium contamination by naturally occurring biogeochemical immobilization. Second, extensive monitoring of pore water in the vadose zone demonstrated that the favored soil-excavation plan would be ineffective in reducing the elevated selenium concentration in ephemeral pools that occurs each winter at Kesterson. Finally, extensive biological monitoring demonstrated that selenium concentrations in the dominant species of upland vegetation at Kesterson was near or equal to ''safe'' levels. The combination of these factors led to a risk-based remedial strategy that would leave the selenium inventory in place, and filling the low-lying areas of Kesterson to prevent formation of ephemeral pools that attract wildlife. Observations that may be applicable to other areas experiencing similar environmental problems include the following: (1) Naturally occurring biogeochemical processes can be the cornerstone of effective remedial strategies: (2) although ''safe levels'' of toxic constituents based on total elemental analysis may be misleading and species-specific targets may be more appropriate. seasonal cycles in speciation and analytical uncertainties make species-specific goals difficult to define; and (3) scientific investigations and fast-track remedial activities must go hand in hand to achieve cost-effective, risk-based remedial strategies. C1 US BUR RECLAMAT,WATER QUAL & ENVIRONM BRANCH,SACRAMENTO,CA 95825. RP BENSON, SM (reprint author), LAWRENCE BERKELEY LAB,DIV EARTH SCI,BERKELEY,CA 94720, USA. NR 31 TC 12 Z9 13 U1 0 U2 3 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9437 J9 J IRRIG DRAIN E-ASCE JI J. Irrig. Drainage Eng-ASCE PD MAY-JUN PY 1993 VL 119 IS 3 BP 471 EP 483 DI 10.1061/(ASCE)0733-9437(1993)119:3(471) PG 13 WC Agricultural Engineering; Engineering, Civil; Water Resources SC Agriculture; Engineering; Water Resources GA LD970 UT WOS:A1993LD97000004 ER PT J AU BRACKETT, CA ACAMPORA, AS SWEITZER, J TANGONAN, G SMITH, MT LENNON, W WANG, KC HOBBS, RH AF BRACKETT, CA ACAMPORA, AS SWEITZER, J TANGONAN, G SMITH, MT LENNON, W WANG, KC HOBBS, RH TI A SCALABLE MULTIWAVELENGTH MULTIHOP OPTICAL NETWORK - A PROPOSAL FOR RESEARCH ON ALL-OPTICAL NETWORKS SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article AB An architectural approach for very-high-capacity wide-area optical networks is presented, and a proposed program of research to address key system and device issues is described. This paper is a summary of a proposal submitted to DARPA for research on all-optical networks. The proposed network is based upon dense multiwavelength technology and is scalable in terms of the number of networked users, the geographical range of coverage, and the aggregate network capacity. Of paramount importance to the achievement of scalability are the notions of wavelength re-use and wavelength translation. With this approach, each user is attached to the network through a generic access station equipped with a small number of optical transmitters and receivers, each operating on a different wavelength. Using this fixed set of transceivers, a clear optical channel is established by connecting each access station to a number of other access stations through a transparent optical interconnect. This distributed optical interconnect is wavelength-selective and electronically controllable, permitting the same limited set of wavelengths to be re-used among other access stations. Furthermore, by exercising the wavelength-selective switches, the wavelength-routed connectivity between stations can be reconfigured as needed. Finally, a multihop overlay network involving wavelength translation and self-routing fast packet switches permits full connectivity, if desired, among the access stations at the individual virtual circuit level. This architecture and its innovative use of both optical and electronic technologies achieves a total independence between the number of available wavelengths and the number of nodes served, thereby introducing true scalability and modularity to optical networks for the first time. As an example of the power of this approach, it is shown in this proposal that using just eight wavelengths, such a network could in principle interconnect a population of 100 million users over a nationwide geography with an expected delay equal to that of 12 hops. If each such user were to access at a rate of 1 Gb/s, an overall pool of network capacity on the order of 10 million Terabits/s would have been created. The rationale behind the approach, the requisite systems and device technologies, and a planned testbed implementation to demonstrate overall technical feasibility of the approach are discussed. C1 COLUMBIA UNIV,DEPT ELECT ENGN,NEW YORK,NY 10027. NO TELECOM,MORRISTOWN,NJ 07962. HUGHES RES LABS,DEPT INFORMAT NETWORKS TECHNOL,MALIBU,CA 90265. HEWLETT PACKARD CORP,DEPT MULTIMEDIA SYST,PALO ALTO,CA 94303. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. ROCKWELL SCI CTR,THOUSAND OAKS,CA 91358. UNITED TECHNOL RES CTR,E HARTFORD,CT 06108. RP BRACKETT, CA (reprint author), BELL COMMUN RES INC,EXPLORATORY OPT NETWORKS RES,MORRISTOWN,NJ 07962, USA. NR 14 TC 170 Z9 174 U1 0 U2 12 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0733-8724 J9 J LIGHTWAVE TECHNOL JI J. Lightwave Technol. PD MAY-JUN PY 1993 VL 11 IS 5-6 BP 736 EP 753 DI 10.1109/50.233237 PG 18 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA LY248 UT WOS:A1993LY24800007 ER PT J AU GREEN, PE COLDREN, LA JOHNSON, KM LEWIS, JG MILLER, CM MORRISON, JF OLSHANSKY, R RAMASWAMI, R SMITH, EH AF GREEN, PE COLDREN, LA JOHNSON, KM LEWIS, JG MILLER, CM MORRISON, JF OLSHANSKY, R RAMASWAMI, R SMITH, EH TI ALL-OPTICAL PACKET-SWITCHED METROPOLITAN-AREA NETWORK PROPOSAL SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article ID AMPLIFIERS AB This paper describes a proposal submitted to DARPA in late 1991 by a consortium consisting of IBM, Los Alamos National Laboratory, GTE Laboratories, British Telecom Dupont Technologies, Lasertron, Micron Optics, University of California at Santa Barbara, and University of Colorado at Boulder to develop a precompetitive, commercially viable all-optical network, architecture using dense optical wavelength division. The objective was to demonstrate a packet-switched high-capacity all-optical LAN/MAN network based on wavelength division multiplexing capable of supporting several hundred to a thousand nodes, each requiring gigabit-per-second throughputs. C1 UNIV CALIF SANTA BARBARA,DEPT ELECT & COMP ENGN,SANTA BARBARA,CA 93106. UNIV COLORADO,DEPT ELECT & COMP ENGN,BOULDER,CO 80309. UNIV COLORADO,DEPT ELECT & COMP ENGN,BOULDER,CO 80309. LASERTRON,BURLINGTON,MA 01803. MICRON OPT,ATLANTA,GA 30329. LOS ALAMOS NATL LAB,COMP NETWORK ENGN GRP,LOS ALAMOS,NM 87545. GTE LABS INC,SYST TECHNOL LAB,DEPT ADV TRANSPORT TECHNIQUES,WALTHAM,MA 02254. BT&D TECHNOL,WILMINGTON,DE 19803. IBM CORP,THOMAS J WATSON RES CTR,YORKTOWN HTS,NY 10598. RP GREEN, PE (reprint author), IBM CORP,RES,YORKTOWN HTS,NY 10598, USA. NR 30 TC 53 Z9 53 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 0733-8724 J9 J LIGHTWAVE TECHNOL JI J. Lightwave Technol. PD MAY-JUN PY 1993 VL 11 IS 5-6 BP 754 EP 763 DI 10.1109/50.233238 PG 10 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA LY248 UT WOS:A1993LY24800008 ER PT J AU BOONE, JL LAERM, J SMITH, MH AF BOONE, JL LAERM, J SMITH, MH TI TAXONOMIC STATUS OF PEROMYSCUS-GOSSYPINUS-ANASTASAE (ANASTASIA ISLAND COTTON MOUSE) SO JOURNAL OF MAMMALOGY LA English DT Article DE PEROMYSCUS-GOSSYPINUS; TAXONOMY; GENETICS; ALLOZYME; MORPHOLOGY ID BIOCHEMICAL POLYMORPHISM; GENETIC-VARIATION; GENUS PEROMYSCUS; POCKET GOPHERS; POPULATIONS; DISTANCE AB Four subspecies of cotton mice (Peromyscus gossypinus) were examined to assess the taxonomic validity and affinities of the mice on Cumberland Island, Georgia, and Anastasia Island, Florida, both of which are presently referred to P. g. anastasae. Genetic analysis of 44 loci in 379 mice from 14 populations (six island, eight mainland) and morphometric analysis of 27 characters on 683 mice from 20 populations were performed. Polymorphic loci and heterozygosity per population averaged 40 and 10%, respectively, and there was no reduction of genetic variability on islands. Insular mice tended to be smaller than mainland mice. Every population was genetically or morphologically different from all other populations for at least one character in pairwise comparisons. However, when all populations were examined simultaneously, the pairwise differences were not significant. While each population was statistically distinct, none was unusually distinct, and neither the Cumberland Island nor Anastasia Island populations of P. g. anastasae warrant recognition as separate subspecies. C1 UNIV GEORGIA,DEPT ECOL,ATHENS,GA 30602. UNIV GEORGIA,INST ECOL,ATHENS,GA 30602. UNIV GEORGIA,DEPT ZOOL,ATHENS,GA 30602. UNIV GEORGIA,MUSEUM NAT HIST,ATHENS,GA 30602. SAVANNAH RIVER ECOL LAB,AIKEN,SC 29802. UNIV GEORGIA,DEPT GENET,ATHENS,GA 30602. UNIV GEORGIA,SCH FOREST RESOURCES,ATHENS,GA 30602. RP BOONE, JL (reprint author), UNIV GEORGIA,SAVANNAH RIVER ECOL LAB,ATHENS,GA 30602, USA. NR 44 TC 5 Z9 5 U1 0 U2 2 PU AMER SOC MAMMALOGISTS PI PROVO PA BRIGHAM YOUNG UNIV, DEPT OF ZOOLOGY, PROVO, UT 84602 SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD MAY PY 1993 VL 74 IS 2 BP 363 EP 375 DI 10.2307/1382392 PG 13 WC Zoology SC Zoology GA LD676 UT WOS:A1993LD67600013 ER PT J AU SHELDON, BW BESMANN, TM MORE, KL MOSS, TS AF SHELDON, BW BESMANN, TM MORE, KL MOSS, TS TI EPITAXIAL NUCLEATION OF POLYCRYSTALLINE SILICON-CARBIDE DURING CHEMICAL VAPOR-DEPOSITION SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID FILAMENT CERAMIC COMPOSITES; REINFORCED SIC COMPOSITES; PHASE FABRICATION; GROWTH; MICROSTRUCTURE; INFILTRATION; CVD AB Polycrystalline silicon carbide was deposited from methyltrichlorosilane in cold-walled and hot-walled reactors, on (100) SiC surface layers that were formed on (100) Si wafers. The initial stages of the process were studied by electron microscopy after relatively short deposition times. Submicron surface features nucleated with a specific crystallographic orientation with respect to the substrate, where h111j planes in theb-SiC substrate coincided with h0001j planes in the a-SiC features. These a-SiC features occurred only at twins on h111j planes of the b-SiC substrate. This demonstrates that nucleation under these conditions is controlled by defects in the substrate. Surface contamination and the reactor configuration also had substantial effects on nucleation. C1 OAK RIDGE ASSOCIATED UNIV,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831. RP SHELDON, BW (reprint author), BROWN UNIV,DIV ENGN,PROVIDENCE,RI 02912, USA. RI More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 24 TC 5 Z9 5 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1993 VL 8 IS 5 BP 1086 EP 1092 DI 10.1557/JMR.1993.1086 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA KZ502 UT WOS:A1993KZ50200023 ER PT J AU VASUDEV, A MORE, KL AILEYTRENT, KS DAVIS, RF AF VASUDEV, A MORE, KL AILEYTRENT, KS DAVIS, RF TI KINETICS AND MECHANISMS OF HIGH-TEMPERATURE CREEP IN POLYCRYSTALLINE ALUMINUM NITRIDE SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CERAMICS; AIN; ALN AB The operative and controlling mechanisms of steady-state creep in hot-pressed AlN have been determined both from kinetic data within the temperature and constant compressive stress ranges of 1470 to 1670 K and 100 to 370 MPa, respectively, and from the microstructural results of TEM. No secondary phases were detected in the bulk or at the grain boundaries using Raman spectroscopy and HREM. The stress exponent was almost-equal-to 1.0 at all temperatures. The activation energies ranged between 558 and 611 kJ/mol. The most prominent microstructural features of the crept samples were elongated grains, strain whorls, and triple-point folds. Dislocations were generated only at the strain whorls in order to relieve the localized stress caused by intraboundary mechanical interaction among the grains. They contributed little to the observed deformation. The controlling mechanism for creep was diffusion-accommodated grain-boundary sliding. This mechanism was accompanied in parallel by relatively small amounts of unaccommodated grain-boundary sliding. Cavitation was not observed. C1 OAK RIDGE NATL LAB,HIGH TEMP MAT LAB,OAK RIDGE,TN 37831. RP VASUDEV, A (reprint author), N CAROLINA STATE UNIV,DEPT MAT SCI & ENGN,BOX 7907,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 36 TC 5 Z9 6 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1993 VL 8 IS 5 BP 1101 EP 1108 DI 10.1557/JMR.1993.1101 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA KZ502 UT WOS:A1993KZ50200025 ER PT J AU HIETALA, SL SMITH, DM HIETALA, VM BRINKER, CJ AF HIETALA, SL SMITH, DM HIETALA, VM BRINKER, CJ TI CLOSED POROSITY ALUMINOSILICATE FOR ELECTRONIC PACKAGING APPLICATIONS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID GEL AB The electrical properties of sol-gel prepared aluminosilicate films were investigated for suitability in electronic applications. The aluminosilicate films exhibited apparent closed porosity and a dielectric constant as low as almost-equal-to 5 with processing temperatures from 373 K to 873 K. The porosity was inaccessible to nitrogen at 77 K, helium at 293 K, and water vapor at 293 K. Both bulk and thin-film samples were analyzed for hydroxyl and carbon contents to elucidate the relative dependence of the measured electrical proper-ties on processing conditions. Experiments indicate it is possible to vary the porosity in bulk material in ways that should improve electrical properties. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP HIETALA, SL (reprint author), UNIV NEW MEXICO,NSF,CTR MICROENGINEERED CERAM,ALBUQUERQUE,NM 87131, USA. NR 18 TC 1 Z9 1 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1993 VL 8 IS 5 BP 1122 EP 1127 DI 10.1557/JMR.1993.1122 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA KZ502 UT WOS:A1993KZ50200028 ER PT J AU HSUEH, CH FERBER, MK AF HSUEH, CH FERBER, MK TI EVALUATIONS OF RESIDUAL AXIAL STRESSES AND INTERFACIAL FRICTION IN NICALON FIBER-REINFORCED MACRO-DEFECT-FREE CEMENT COMPOSITES SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID FIBER PULL-OUT; CERAMIC COMPOSITES; MATRIX AB The residual axial stress and the interfacial frictional stress of Nicalon fibre-reinforced macro-defect-free cement composites have been evaluated using the indentation technique. In these composites, both the residual axial stress in the fibre and the interfacial bonding are relatively high compared to other ceramic composites. Owing to the high residual axial stress, Poisson's effect can be ignored in analysing the stress-displacement relation of the fibre, and the interfacial frictional stress along the sliding length can be assumed to be a constant during indentation loading and unloading. Because of the strong interfacial bonding, consideration of the upper bound of the sliding zone length during unloading is essential. The sliding zone length during unloading is limited by the debond length at peak loading. The theoretical predictions of stress-displacement relations are in excellent agreement with the experimental results. 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 15 TC 8 Z9 8 U1 1 U2 1 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAY 1 PY 1993 VL 28 IS 9 BP 2551 EP 2556 DI 10.1007/BF01151691 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA LB030 UT WOS:A1993LB03000040 ER PT J AU RAWERS, JC MAUPIN, HE AF RAWERS, JC MAUPIN, HE TI METAL INTERMETALLIC COMPOSITES FORMED BY REACTION-SINTERING METAL FOILS SO JOURNAL OF MATERIALS SCIENCE LETTERS LA English DT Article RP RAWERS, JC (reprint author), US BUR MINES,ALBANY RES CTR,ALBANY,OR 97321, USA. NR 10 TC 28 Z9 29 U1 0 U2 2 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0261-8028 J9 J MATER SCI LETT JI J. Mater. Sci. Lett. PD MAY 1 PY 1993 VL 12 IS 9 BP 637 EP 639 DI 10.1007/BF00465576 PG 3 WC Materials Science, Multidisciplinary SC Materials Science GA LB031 UT WOS:A1993LB03100008 ER PT J AU CORONES, J SUN, ZM AF CORONES, J SUN, ZM TI SIMULTANEOUS RECONSTRUCTION OF MATERIAL AND TRANSIENT SOURCE PARAMETERS USING THE INVARIANT IMBEDDING METHOD SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Article ID DISSIPATIVE WAVE-EQUATION; INVERSE SCATTERING; TIME DOMAIN AB This paper extends the time domain wave splitting and invariant imbedding method to an inhomogeneous wave equation with a source term: u(xx)-u(tt)+A(x)u(x)=2D(x)i'(t). The direct scattering and inverse source problems of this equation are studied. Operators j+/- that map the source function into the scattered waves at the edges of the slab are defined. A system of coupled nonlinear integrodifferential equations for these scattering operator kernels is obtained. The direct scattering problem is to obtain the scattering operator kernels J+/- and R+ when parameters A and D are given. The inverse problem is to simultaneously reconstruct A(x) and D(x) from the scattering operator kernels R+(0,t), 0 less-than-or-equal-to t less-than-or-equal-to 2 and J-(0,t), 0 99.5% lattice relaxation with minimal threading dislocation content. Multiple quantum well superlattices grown at 400-degrees-C upon this buffer exhibited strong excitonic absorption at 1.33 mum and good surface morphology with slight crosshatching. A Fabry-Perot-cavity reflectance modulator grown at 400-degrees-C on this buffer exhibited strong excitonic absorption and good reflectance contrast at 1.33 mum. RP HAMMONS, BE (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 13 TC 6 Z9 6 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 MAY-JUN PY 1993 VL 11 IS 3 BP 932 EP 934 DI 10.1116/1.586743 PG 3 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA LH228 UT WOS:A1993LH22800083 ER PT J AU VALENTINE, GA AF VALENTINE, GA TI NOTE ON THE DISTRIBUTION OF BASALTIC VOLCANISM ASSOCIATED WITH LARGE SILICIC CENTERS SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Note ID LONG-VALLEY CALDERA; RHYOLITIC MAGMA; CALIFORNIA; EVOLUTION; COMPLEX; FIELD; CONSTRAINTS; GENERATION; INTRUSION; MOUNTAIN RP VALENTINE, GA (reprint author), LOS ALAMOS NATL LAB,GEOANAL GRP EES5,LOS ALAMOS,NM 87545, USA. NR 25 TC 9 Z9 9 U1 0 U2 1 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 MAY PY 1993 VL 56 IS 1-2 BP 167 EP 170 DI 10.1016/0377-0273(93)90058-Y PG 4 WC Geosciences, Multidisciplinary SC Geology GA LE582 UT WOS:A1993LE58200011 ER PT J AU MINGALEEV, AR NILSEN, J PIKUZ, SA ROMANOVA, VM FAENOV, AY SHELKOVENKO, TA ERMATOV, SA AF MINGALEEV, AR NILSEN, J PIKUZ, SA ROMANOVA, VM FAENOV, AY SHELKOVENKO, TA ERMATOV, SA TI SPECTRA OF MULTICHARGE NICKEL AND COPPER IONS IN X-PINCH PLASMA SO KVANTOVAYA ELEKTRONIKA LA Russian DT Article ID ISOELECTRONIC SEQUENCE AB L-spectra of Ni and Cu ions formed in X-pinch plasma have been registered. Using a fast Johann spectrograph and registration with spatial resolution, spectra have been observed both in hot dense plasma and in relatively cold recombining plasma flying away out of the hot point. The wavelengths of several spectral lines of multicharge Ni and Cu ions have been measured with relative error DELTAlambda/lambda approximately 10(-4). Through calculations allowed a number of new Na-like satellite lines to be identified. C1 ALL RUSSIAN PHYSICOTECH & RADIOENGN MEASUREMENTS RES INST,MENDELEYEVSK,RUSSIA. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP MINGALEEV, AR (reprint author), PN LEBEDEV PHYS INST,MOSCOW,RUSSIA. RI Romanova, Vera/M-6922-2015; Mingaleev, Albert/M-8156-2015; Shelkovenko, Tatiana/M-8254-2015; Pikuz, Sergey/M-8231-2015 NR 23 TC 3 Z9 3 U1 0 U2 0 PU LEBEDEV PHYSICAL INST KVANTOVAYA ELEKTRONIKA JOURNAL PI MOSCOW GSP-1 PA LENINSKII PROSPEKT 53, 117924 MOSCOW GSP-1, RUSSIA SN 0368-7147 J9 KVANTOVAYA ELEKTRON+ JI Kvantovaya Elektron. PD MAY PY 1993 VL 20 IS 5 BP 461 EP 470 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA LW059 UT WOS:A1993LW05900007 ER PT J AU VAKNIN, D KJAER, K RINGSDORF, H BLANKENBURG, R PIEPENSTOCK, M DIEDERICH, A LOSCHE, M AF VAKNIN, D KJAER, K RINGSDORF, H BLANKENBURG, R PIEPENSTOCK, M DIEDERICH, A LOSCHE, M TI X-RAY AND NEUTRON REFLECTIVITY STUDIES OF A PROTEIN MONOLAYER ADSORBED TO A FUNCTIONALIZED AQUEOUS SURFACE SO LANGMUIR LA English DT Letter ID AIR-WATER-INTERFACE; STREPTAVIDIN; DIFFRACTION; LAYERS AB We report the structural organization of a protein, streptavidin, specifically bound at aqueous surfaces to lipid monolayers functionalized by biotinylated head groups. X-ray and neutron reflectivity data with H2O and D2O as subphases are consistent with the formation of homogeneous monomolecular protein layers (thickness d(pr) almost-equal-to 42 +/- 2 angstrom) directly underneath the lipid. A new approach of analyzing all four data sets in terms of one general model reveals the dry volume of the protein, its average lateral density at the interface, and the amount of water interpenetrating the protein film. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES LAB,AMES,IA 50011. RISO NATL LAB,DEPT PHYS,DK-4000 ROSKILDE,DENMARK. UNIV MAINZ,INST ORGAN CHEM,W-6500 MAINZ,GERMANY. UNIV MAINZ,INST PHYS CHEM,W-6500 MAINZ,GERMANY. RI Losche, Mathias/J-2986-2013; Vaknin, David/B-3302-2009 OI Losche, Mathias/0000-0001-6666-916X; Vaknin, David/0000-0002-0899-9248 NR 25 TC 31 Z9 32 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY PY 1993 VL 9 IS 5 BP 1171 EP 1174 DI 10.1021/la00029a003 PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA LD681 UT WOS:A1993LD68100003 ER PT J AU SEED, T CARNES, B TOLLE, D FRITZ, T AF SEED, T CARNES, B TOLLE, D FRITZ, T TI BLOOD RESPONSES UNDER CHRONIC LOW DAILY DOSE GAMMA-IRRADIATION .2. DIFFERENTIAL PRECLINICAL RESPONSES OF IRRADIATED FEMALE DOGS IN PROGRESSION TO EITHER APLASTIC-ANEMIA OR MYELOPROLIFERATIVE DISEASE SO LEUKEMIA RESEARCH LA English DT Article DE APLASTIC ANEMIA; BLOOD; CHRONIC LOW-DOSE IRRADIATION; LEUKEMIA; MYELOPROLIFERATIVE DISEASE AB Female beagle dogs were chronically exposed to low daily doses of Co-60 gamma rays (7.5 cGy day-1) and responded in one of three distinct hemopathological patterns. These patterns, reflective of distinct subgroups, were characterized by (a) low radioresistance resulting in progressive hematopoietic suppression, terminal aplastic anemia (AA), and relatively short (<400 days) survival (-S-AA subgroup); (b) high radioresistance, initially coupled with strong but aberrant regenerative hematopoiesis, and later with the development of myeloproliferative disease (MPD) (+-R-MPD subgroup); and (c) high radioresistance, coupled with an early phase of strong regenerative hematopoiesis, but later with no myeloproliferative disease (+R-nonMPD subgroup). In this study, the changes in circulating blood cell levels (granulocytes, monocytes, erythrocytes, lymphocytes and platelets) were sequentially assessed in time and fitted to a flexible, quadratic-linear-type response model previously developed. These analyses provided definition to (a) an initial suppressive, radiotoxic phase and (b) the subsequent recovery phase for each of these subgroups. The magnitude and severity of blood cell loss during the initial suppressive phase was generally greatest in the -S-AA subgroup and lowest in the +R-nonMPD subgroup, with the +R-MPD subgroup showing intermediate level responses. A notable exception included a very high net loss of blood granulocytes by the +R-nonMPD subgroup relative to the other two subgroups. By contrast, the magnitude of blood cell restoration, as well as blood cell maintenance levels during the secondary, recovery phase, was generally highest in the +R-MPD subgroup, of intermediate strength in the +R-nonMPD subgroup, and extremely weak or absent in the -S-AA subgroup. Notable exceptions were in the +R-nonMPD subgroup's high recovery rates of monocyte and lymphocyte blood levels, as well as the high maintenance levels of blood granulocytes during recovery. These results are consistent with our earlier observations of blood responses of chronically irradiated male dogs, in that subgroups of female dogs prone to specific radiogenic hematopathologies (i.e. AA and MPD) can be readily identified and staged in specific preclinical periods by a series of marked differential, blood responses. RP SEED, T (reprint author), ARGONNE NATL LAB,DIV BIOL & MED RES,RADIAT HEMATOL GRP,9700 S CASS AVE,BIM-202,ARGONNE,IL 60439, USA. NR 29 TC 2 Z9 2 U1 2 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0145-2126 J9 LEUKEMIA RES JI Leuk. Res. PD MAY PY 1993 VL 17 IS 5 BP 411 EP 420 DI 10.1016/0145-2126(93)90096-4 PG 10 WC Oncology; Hematology SC Oncology; Hematology GA LB863 UT WOS:A1993LB86300003 PM 8501968 ER PT J AU FLEGAL, AR GARRISON, DL NIEMEYER, S AF FLEGAL, AR GARRISON, DL NIEMEYER, S TI LEAD ISOTOPIC DISEQUILIBRIA BETWEEN PLANKTON ASSEMBLAGES AND SURFACE WATERS REFLECT LIFE-CYCLE STRATEGIES OF COASTAL POPULATIONS WITHIN A NORTHEAST PACIFIC UPWELLING REGIME SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Note ID CALIFORNIA CURRENT; PHYTOPLANKTON; INDUSTRIAL; FILAMENTS; TRACERS; EDDIES; FLUXES; JETS AB Stable lead isotopic compositions (Pb-204, Pb-206, Pb-207, Pb-208) were determined for net plankton samples from a northeast Pacific upwelling regime, following a study that revealed pronounced isotopic composition differences in seawater within that regime. Lead isotopic ratios of the plankton were positively correlated with those of the seawater. Both evidenced the predominance of two sources of industrial Pb (North American and Asian aerosols) in northeast Pacific surface waters, which substantiated the postulate that essentially all (> 90%) of the Pb in the northeast Pacific biome derives from anthropogenic emissions. However, the isotopic compositions of plankton and seawater collected concurrently from the same locations were often markedly dissimilar. The isotopic disequilibria are attributed to rapid vertical transport of plankton through water masses with different isotopic compositions during upwelling events. That proposed transport is consistent with associated observations of differences in species composition and nutrient concentrations in the upwelling regime. It is also consistent with the hypothesis that some phytoplankton species form rapidly sinking resting spores and senescent cells as a life cycle strategy in temperate coastal waters where ephemeral upwelling events episodically disrupt stratified conditions. C1 LAWRENCE LIVERMORE NATL LAB,DIV NUCL CHEM,LIVERMORE,CA 94550. RP FLEGAL, AR (reprint author), UNIV CALIF SANTA CRUZ,INST MARINE SCI,SANTA CRUZ,CA 95064, USA. NR 34 TC 2 Z9 2 U1 0 U2 3 PU AMER SOC LIMNOLOGY OCEANOGRAPH PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD MAY PY 1993 VL 38 IS 3 BP 670 EP 678 PG 9 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA LK314 UT WOS:A1993LK31400021 ER PT J AU HSUEH, CH AF HSUEH, CH TI EMBEDDED-END DEBONDING DURING FIBER PULL-OUT SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Letter ID ELASTIC MATRIX; COMPOSITES; STRENGTH; STRESS AB Interfacial debonding at the embedded end rather than at the loaded end of the fiber during fiber pull-out is considered in the present study. When the embedded-end face of the fiber is not bonded to the matrix, the local maximum interfacial shear stress occurs not only at the loaded end but also at the embedded end. Specifically when both the Young's modulus ratio and the radius ratio of the fiber to the matrix are large, the interfacial shear stress at the embedded end can exceed that at the loaded end, and this results in embedded-end debonding. The calculated interfacial shear stresses at the embedded end based on different models are compared and the criterion for embedded-end debonding is described. 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 11 TC 4 Z9 4 U1 0 U2 2 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 MAY 1 PY 1993 VL 163 IS 1 BP L1 EP L4 DI 10.1016/0921-5093(93)90589-7 PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA LF639 UT WOS:A1993LF63900018 ER PT J AU CARR, JR MAO, NH AF CARR, JR MAO, NH TI A GENERAL-FORM OF PROBABILITY KRIGING FOR ESTIMATION OF THE INDICATOR AND UNIFORM TRANSFORMS SO MATHEMATICAL GEOLOGY LA English DT Article DE PROBABILITY KRIGING; INDICATOR TRANSFORM; UNIFORM TRANSFORM; COKRIGING; PAIRED-SUM SEMI-VARIOGRAMS ID PROGRAM AB Probability kriging is implemented in a general cokriging procedure (cf. Myers, 1982) for estimating both the indicator and uniform transforms. Paired-sum semi-variograms are used to facilitate the modeling of the cross-covariance between the uniform transform and each indicator transform. Estimates of the uniform transform are averaged over all cutoffs, the average used to derive an estimate of the original data. This estimate can be biased with respect to the mean data value, but is unbiased with respect to the data median. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP CARR, JR (reprint author), UNIV NEVADA,DEPT GEOL SCI,RENO,NV 89557, USA. NR 13 TC 9 Z9 9 U1 0 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0882-8121 J9 MATH GEOL JI Math. Geol. PD MAY PY 1993 VL 25 IS 4 BP 425 EP 438 DI 10.1007/BF00894777 PG 14 WC Geosciences, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Geology; Mathematics GA LD304 UT WOS:A1993LD30400001 ER PT J AU FINCKE, JR SWANK, WD JEFFERY, CL MANCUSO, CA AF FINCKE, JR SWANK, WD JEFFERY, CL MANCUSO, CA TI SIMULTANEOUS MEASUREMENT OF PARTICLE-SIZE, VELOCITY AND TEMPERATURE SO MEASUREMENT SCIENCE AND TECHNOLOGY LA English DT Article ID PLASMA AB A measurement technique for simultaneously obtaining the size, velocity and temperature of particles entrained in thermal plasma jets is described. Particle size and velocity are obtained from a combination laser sizing system and laser Doppler velocimeter (LDV). The particle temperature is determined by two-colour pyrometry and the data rate is a measure of relative particle number density. Since particle size, velocity and temperature are measured simultaneously, cold, solid particles or unmelts are identified and their relative number density can be quantified. Typical data are presented. RP EG&G IDAHO INC, IDAHO NATL ENGN LAB, IDAHO FALLS, ID 83415 USA. NR 17 TC 30 Z9 31 U1 3 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-0233 EI 1361-6501 J9 MEAS SCI TECHNOL JI Meas. Sci. Technol. PD MAY PY 1993 VL 4 IS 5 BP 559 EP 565 DI 10.1088/0957-0233/4/5/003 PG 7 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA LC069 UT WOS:A1993LC06900003 ER PT J AU RIZZO, HF MASSALSKI, TB NASTASI, M AF RIZZO, HF MASSALSKI, TB NASTASI, M TI METASTABLE CRYSTALLINE AND AMORPHOUS STRUCTURES FORMED IN THE CU-W SYSTEM BY VAPOR-DEPOSITION SO METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID THIN-FILMS; ALLOYS; AU AB The possibility of producing nonequilibrium amorphous and crystalline phases in the Cu-W system is of interest because, under equilibrium conditions, no mutual solubility is expected between Cu and W. Triode sputtered coatings (45 to 150 mum thick, produced at deposition rates between 20 and 150 angstrom/s) consisted of amorphous and metastable crystalline phases. The latter remained decomposition-resistant on heating to various temperatures between 340-degrees-C and 600-degrees-C (the maximum temperature of exposure). The amorphous phase in such coatings crystallized on heating into a metastable body-centered cubic (bcc) phase, and the crystallization temperature (T(x)) was found to decrease across the phase diagram from 450-degrees-C to 340-degrees-C as the percentage of W increased from 26 to 60 at. pct. Samples containing amorphous phase regions, when subjected to heating between 150-degrees-C and 250-degrees-C, showed an unusual rapid precipitation of Cu at the sample surface, indicating an easy diffusion of the Cu component. This occurred without crystallization of the remaining slightly tungsten-enriched amorphous matrix. Microhardness measurements in sputtered two-phase amorphous and bcc regions have shown that in alloys of the same composition, the amorphous phase was always softer than the bcc solid solution phase. X-ray, microprobe, and optical evidence suggests that the amorphous films deposited at very low temperatures (i.e., at liquid N2) may subsequently undergo a phase separation upon heating to room temperature and prior to crystallization. Earlier work and present studies of vapor-deposited alloys in this system confirm that the observed phases and microstructures can be related to free energy trends estimated from thermodynamic considerations and to specific deposition parameters, such as the substrate temperature and the deposition rates, which influence the kinetics. C1 UNIV GOTTINGEN,INST MET PHYS,W-3400 GOTTINGEN,GERMANY. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP RIZZO, HF (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 22 TC 22 Z9 24 U1 1 U2 4 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0360-2133 J9 METALL TRANS A PD MAY PY 1993 VL 24 IS 5 BP 1027 EP 1037 DI 10.1007/BF02657233 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA LA785 UT WOS:A1993LA78500003 ER PT J AU NEUBIG, RR SKLAR, LA AF NEUBIG, RR SKLAR, LA TI SUBSECOND MODULATION OF FORMYL PEPTIDE-LINKED GUANINE-NUCLEOTIDE-BINDING PROTEINS BY GUANOSINE 5'-O-(3-THIO)TRIPHOSPHATE IN PERMEABILIZED NEUTROPHILS SO MOLECULAR PHARMACOLOGY LA English DT Article ID BETA-ADRENERGIC-RECEPTOR; ADENYLATE-CYCLASE; INTRINSIC FLUORESCENCE; REGULATORY PROTEINS; MECHANISM; AGONIST; RECONSTITUTION; LOCALIZATION; INHIBITION; ACTIVATION AB Rapid activation of guanine nucleotide-binding protein (G protein)-mediated signal transduction mechanisms occurs in many tissues. The human neutrophil provides a useful model for studying the mechanisms of these fast processes. Fluorescent chemotactic tetrapeptide and pentapeptide exhibit 30-50% quenching of fluorescence upon binding to the neutrophil formyl peptide receptor, and their binding affinity is strongly regulated by the G protein G(i). We used rapid kinetic spectrofluorometric methods to study the assembly and disassembly of the ternary complex of ligand, receptor, and G protein in digitonin-permeabilized human neutrophils. Binding was studied up to 20 nm ligand, where the half-time for association was 1.2 sec. The rate constant of association was near that for diffusion-limited reactions of ligands and proteins, 2 x 10(7) m-1 sec-1. The rate of uncoupling of formyl peptide receptor from G protein in the presence of high concentrations of guanine nucleotide was greater-than-or-equal-to 5 sec-1 (i.e., t1/2 of 0.14 sec). Thus, disassembly of the formyl peptide receptor-G protein complex occurs in the millisecond time domain and may be faster than the next step in the signal transduction process. C1 UNIV MICHIGAN,DEPT INTERNAL MED,ANN ARBOR,MI 48109. UNIV NEW MEXICO,DEPT CYTOMETRY,ALBUQUERQUE,NM 87131. LOS ALAMOS NATL LAB,DIV LIFE SCI,LOS ALAMOS,NM 87545. RP NEUBIG, RR (reprint author), UNIV MICHIGAN,DEPT PHARMACOL,M6322 MED SCI BLDG 1,ANN ARBOR,MI 48109, USA. FU NCRR NIH HHS [RR01315]; NIAID NIH HHS [AI19032]; NIGMS NIH HHS [GM39561] NR 26 TC 22 Z9 22 U1 0 U2 0 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 0026-895X J9 MOL PHARMACOL JI Mol. Pharmacol. PD MAY PY 1993 VL 43 IS 5 BP 734 EP 740 PG 7 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA LD299 UT WOS:A1993LD29900012 PM 8502230 ER PT J AU BELAK, JF AF BELAK, JF TI NANOTRIBOLOGY SO MRS BULLETIN LA English DT Article ID ATOMIC-FORCE MICROSCOPE; SCALE FRICTION; SURFACE FORCES; TRIBOLOGY; MONOLAYER; TIP RP BELAK, JF (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV CONDENSED MATTER PHYS,LIVERMORE,CA 94550, USA. NR 25 TC 25 Z9 25 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0883-7694 J9 MRS BULL JI MRS Bull. PD MAY PY 1993 VL 18 IS 5 BP 15 EP 19 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA LD300 UT WOS:A1993LD30000002 ER PT J AU SALMERON, MB AF SALMERON, MB TI USE OF THE ATOMIC FORCE MICROSCOPE TO STUDY MECHANICAL-PROPERTIES OF LUBRICANT LAYERS SO MRS BULLETIN LA English DT Article RP SALMERON, MB (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 13 TC 33 Z9 33 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0883-7694 J9 MRS BULL JI MRS Bull. PD MAY PY 1993 VL 18 IS 5 BP 20 EP 25 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA LD300 UT WOS:A1993LD30000003 ER PT J AU BELAK, J BOERCKER, DB STOWERS, IF AF BELAK, J BOERCKER, DB STOWERS, IF TI SIMULATION OF NANOMETER-SCALE DEFORMATION OF METALLIC AND CERAMIC SURFACES SO MRS BULLETIN LA English DT Article ID DYNAMICS; TIP; NANOINDENTATION; INDENTATION; ADHESION; SILICON RP BELAK, J (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV CONDENSED MATTER PHYS,LIVERMORE,CA 94550, USA. NR 37 TC 57 Z9 58 U1 0 U2 5 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0883-7694 J9 MRS BULL JI MRS Bull. PD MAY PY 1993 VL 18 IS 5 BP 55 EP 60 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA LD300 UT WOS:A1993LD30000008 ER PT J AU KAUFMANN, E AF KAUFMANN, E TI AS THE PRESIDENTS SEE IT - NUCLEATION WAS MORE FUN THAN GROWTH SO MRS BULLETIN LA English DT Article RP KAUFMANN, E (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, 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 MAY PY 1993 VL 18 IS 5 BP 65 EP 65 PG 1 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA LD300 UT WOS:A1993LD30000009 ER PT J AU WHITE, W AF WHITE, W TI A YEAR OF CHANGE SO MRS BULLETIN LA English DT Article RP WHITE, W (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN, 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 MAY PY 1993 VL 18 IS 5 BP 65 EP 66 PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA LD300 UT WOS:A1993LD30000010 ER PT J AU LIU, P SICILIANO, J WHITE, B LEGERSKI, R CALLEN, D REEDERS, S SICILIANO, MJ THOMPSON, LH AF LIU, P SICILIANO, J WHITE, B LEGERSKI, R CALLEN, D REEDERS, S SICILIANO, MJ THOMPSON, LH TI REGIONAL MAPPING OF HUMAN DNA EXCISION REPAIR GENE ERCC4 TO CHROMOSOME-16P13.13-P13.2 SO MUTAGENESIS LA English DT Article ID ACUTE MYELOMONOCYTIC LEUKEMIA; SISTER-CHROMATID-EXCHANGE; COMPLEMENTATION GROUP-D; XERODERMA-PIGMENTOSUM; CHROMOSOME 19; CHO CELLS; GROUP-H; MUTANTS; HYBRIDIZATION; EOSINOPHILS AB Mitomycin C (MMC)-resistant interspecific somatic cell hybrids made between human cells and the MMC-sensitive, Chinese hamster ovary (CHO) excision repair-deficient UV41 cells generally contained human chromosome 16, while other human chromosomes were randomly present. MMC-sensitive and -resistant subclones were isolated from resistant clones, and resistance generally segregated concordantly with human chromosome 16 markers. UV radiation survival analysis of subclones indicated that MMC and UV resistance were correlated. Therefore, the complementing gene, Excision Repair Cross Complementing 4 (ERCC4), was assigned to human chromosome 16. Complementation of UV41 by human cells derived from patients with xeroderma pigmentosum groups A, C, D and F excluded ERCC4 from involvement in those disease syndromes. Resistant hybrids containing only portions of chromosome 16 were identified by the lack of concordance of multiple chromosome 16 markers. When such hybrids were used as a source of probe for fluorescent in situ hybridization onto normal human metaphases, the only region of chromosome 16 identified as being consistently present was 16p13.1-p13.3. Genetic marker analysis of informative hybrids with mapped probes refined the position of ERCC4 to 16p13.13-p13.2 and allowed the following order of markers within the region to be established: pter- (PRM1, D16S215)-D16S213-D16S53-(D16S214,ERCC4)-D16S3-D16S96-cen. C1 UNIV TEXAS,MD ANDERSON CANC CTR,DEPT MOLEC GENET,BOX 45,1515 HOLCOMBE BLVD,HOUSTON,TX 77030. ADELAIDE CHILDRENS HOSP INC,CYTOGENET UNIT,ADELAIDE,SA 5006,AUSTRALIA. YALE UNIV,SCH MED,DEPT NEPHROL,NEW HAVEN,CT 06510. LAWRENCE LIVERMORE NATL LAB,BIOL & BIOTECHNOL RES PROGRAM,LIVERMORE,CA 94550. RI Liu, Paul/A-7976-2012; Callen, David/G-1975-2012 OI Liu, Paul/0000-0002-6779-025X; FU NCI NIH HHS [CA55164, CA04484, CA34936] NR 39 TC 22 Z9 22 U1 0 U2 0 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 MAY PY 1993 VL 8 IS 3 BP 199 EP 205 DI 10.1093/mutage/8.3.199 PG 7 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA LE533 UT WOS:A1993LE53300007 PM 8332082 ER PT J AU SCHIPPER, L HOWARTH, R ANDERSSON, B PRICE, L AF SCHIPPER, L HOWARTH, R ANDERSSON, B PRICE, L TI ENERGY USE IN DENMARK - AN INTERNATIONAL PERSPECTIVE SO NATURAL RESOURCES FORUM LA English DT Article ID EFFICIENCY AB This paper reviews the evolution of energy use in Denmark since the early 1970s, in order to shed light on the future path of energy use in Denmark, with particular emphasis on the role of energy efficiency. Improvements in end-use energy efficiency reduced primary energy requirements in Denmark by 22% between 1972 and 1988. This change accounts for two-thirds of the decline in the ratio of energy use to gross domestic product that occurred during this time: the rest of the decline was caused by changes in the mix of goods and services produced and consumed by the Danes. Total energy savings achieved between 1972 and 1988 in Denmark ranked among the highest measured in any major OECD country. Overall, most of the energy savings in Denmark were brought about through improvements in technology. Short-term changes in consumer behaviour were significant in reducing energy needs for space heating and transport. An important stimulus for improved efficiency was higher energy prices, led in no small part by significant taxes imposed on small consumers of heating oil, electricity and motor fuels. C1 STOCKHOLM ENVIRONM INST,STOCKHOLM,SWEDEN. STOCKHOLM SCH BUSINESS,STOCKHOLM,SWEDEN. RP SCHIPPER, L (reprint author), LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,ENERGY ANAL PROGRAM,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. OI Howarth, Richard/0000-0003-3182-7345 NR 21 TC 10 Z9 12 U1 0 U2 1 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0165-0203 J9 NAT RESOUR FORUM PD MAY PY 1993 VL 17 IS 2 BP 83 EP 103 PG 21 WC Environmental Sciences; Environmental Studies SC Environmental Sciences & Ecology GA LF497 UT WOS:A1993LF49700001 ER PT J AU BUHMANN, J KUHNEL, H AF BUHMANN, J KUHNEL, H TI COMPLEXITY OPTIMIZED DATA CLUSTERING BY COMPETITIVE NEURAL NETWORKS (VOL 5, PG 75, 1993) SO NEURAL COMPUTATION LA English DT Correction, Addition ID VECTOR QUANTIZATION; ENTROPY AB Data clustering is a complex optimization problem with applications ranging from vision and speech processing to data transmission and data storage in technical as well as in biological systems. We discuss a clustering strategy that explicitly reflects the tradeoff between simplicity and precision of a data representation. The resulting clustering algorithm jointly optimizes distortion errors and complexity costs. A maximum entropy estimation of the clustering cost function yields an optimal number of clusters, their positions, and their cluster probabilities. Our approach establishes a unifying framework for different clustering methods like K-means clustering, fuzzy clustering, entropy constrained vector quantization, or topological feature maps and competitive neural networks. C1 LAWRENCE LIVERMORE NATL LAB,DIV COMPUTAT PHYS,LIVERMORE,CA 94550. TECH UNIV MUNICH,DEPT PHYS,W-8046 GARCHING,GERMANY. NR 31 TC 0 Z9 0 U1 0 U2 0 PU MIT PRESS PI CAMBRIDGE PA 55 HAYWARD ST JOURNALS DEPT, CAMBRIDGE, MA 02142 SN 0899-7667 J9 NEURAL COMPUT JI Neural Comput. PD MAY PY 1993 VL 5 IS 3 BP 503 EP & PG 0 WC Computer Science, Artificial Intelligence SC Computer Science GA KZ513 UT WOS:A1993KZ51300017 ER PT J AU UNAL, C NELSON, R HAYTCHER, E AF UNAL, C NELSON, R HAYTCHER, E TI A PHENOMENOLOGICAL MODEL OF THE THERMAL-HYDRAULICS OF CONVECTIVE BOILING DURING THE QUENCHING OF HOT ROD BUNDLES .3. MODEL ASSESSMENT USING WINFRITH STEADY-STATE, POST-CHF, VOID-FRACTION AND HEAT-TRANSFER MEASUREMENTS AND BERKELEY TRANSIENT-REFLOOD TEST DATA SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article ID FLOW AB Alter completion and assessment of the thermal-hydraulic model developed in companion papers, we performed further independent assessment calculations using recently available Winfrith steady-state, post-CHF, void-fraction and heat-transfer data, and Berkeley transient-reflood test data. This paper discusses the results of those calculations. The thermal-hydraulic model in the Transient Reactor Analysis Code, Modification 2 (TRAC/PF1-MOD2, or simply TRAC), was used to predict the axial variation of void fraction as measured in Winfrith post-CHF tests. The predictions for reflood calculations were reasonable. The model correctly predicted the trends in void fraction due to the effect of pressure and power, with the effect of pressure being more apparent than that of heat flux. The effects of pressure, test-section power, and flow rate on the axial variation of tube wall temperature are predicted reasonably well for a large range of operating parameters. The predicted precursory cooling rates in Berkeley transient-reflood tests were in reasonably good agreement with the measured data. For high-test section input powers, oscillations associated with the void-fraction predictions observed. The predicted quench-front velocities (rewetting velocities) and their variations along the test tube were also found to be in reasonably good agreement with measured data. RP UNAL, C (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 20 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD MAY PY 1993 VL 140 IS 2 BP 211 EP 227 DI 10.1016/0029-5493(93)90077-M PG 17 WC Nuclear Science & Technology SC Nuclear Science & Technology GA LK009 UT WOS:A1993LK00900006 ER PT J AU ZWEBEN, SJ DARROW, DS FREDRICKSON, ED MYNICK, HE AF ZWEBEN, SJ DARROW, DS FREDRICKSON, ED MYNICK, HE TI ANOMALOUS DELAYED LOSS OF TRAPPED D-D FUSION PRODUCTS IN TFTR SO NUCLEAR FUSION LA English DT Article ID IONS AB A new anomalous delayed loss of D-D fusion products has been measured at the bottom of the TFTR vessel. This loss is delayed by about 0.2 s with respect to the usual prompt first orbit loss, and has a correspondingly lower energy, i.e. about half the fusion product birth energy. This loss process dominates the total fusion product loss measured 90 degrees below the midplane for plasma currents I greater than or equal to 1.8 MA and major radii near R = 2.45 m, e.g. for recent TFTR supershots. This delayed feature can occur without large coherent MHD activity, although it can be strongly modulated by such activity. Several possible causes for this phenomenon are discussed, but no clear explanation for this delayed loss has yet been found. RP ZWEBEN, SJ (reprint author), PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 12 TC 20 Z9 20 U1 0 U2 0 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 1993 VL 33 IS 5 BP 705 EP 724 DI 10.1088/0029-5515/33/5/I03 PG 20 WC Physics, Fluids & Plasmas SC Physics GA MJ264 UT WOS:A1993MJ26400003 ER PT J AU DUONG, HH HEIDBRINK, WW STRAIT, EJ PETRIE, TW LEE, R MOYER, RA WATKINS, JG AF DUONG, HH HEIDBRINK, WW STRAIT, EJ PETRIE, TW LEE, R MOYER, RA WATKINS, JG TI LOSS OF ENERGETIC BEAM IONS DURING TAE INSTABILITIES SO NUCLEAR FUSION LA English DT Article ID INDUCED ALFVEN EIGENMODES; FUSION ALPHA-PARTICLES; DIII-D TOKAMAK; SAWTOOTH OSCILLATIONS; DRIVEN INSTABILITIES; TEST REACTOR; PLASMA; CONFINEMENT; EXCITATION; STABILITY AB Toroidicity induced Alfven eigenmodes (TAE) are observed in the DIII-D tokamak when energetic beam ions (similar to 75 keV) are used to destabilize the mode. Measurements of the neutron emission indicate that up to 70% of the injected power is lost during strong TAE activity. Measurements of the poloidal distribution of fast ion losses suggest that the losses are greatest near the vessel midplane. Fast ion losses in discharges with combined fishbones and TAE bursts are 1.5 to 2 times greater than losses in fishbone discharges without TAE activity. The scaling of fast ion losses with MHD mode amplitude exhibits no threshold in the mode amplitude, suggesting that mode particle pumping is the dominant loss mechanism. C1 GEN ATOM CO,SAN DIEGO,CA. UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024. SANDIA NATL LABS,ALBUQUERQUE,NM. RP DUONG, HH (reprint author), UNIV CALIF IRVINE,DEPT PHYS,IRVINE,CA 92717, USA. NR 38 TC 101 Z9 101 U1 0 U2 3 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 1993 VL 33 IS 5 BP 749 EP 765 DI 10.1088/0029-5515/33/5/I06 PG 17 WC Physics, Fluids & Plasmas SC Physics GA MJ264 UT WOS:A1993MJ26400006 ER PT J AU AXEN, D BOUGEROLLE, S SOBIE, R EIGEN, G DEJONGH, F HITLIN, D KELSEY, M KLEIN, M MINCER, A WISNIEWSKI, W WOLF, R ARROYO, C AU, Y BALTAY, C BOLTON, T BAZARKO, A CAMILLERI, L HYATT, E MANLY, S RABINOWITZ, S ROWSON, PC SELIGMAN, S SHAEVITZ, MH SMITH, S STEINER, RV ABT, I ALZOFON, D ARNETT, D BARRERA, F BELL, R BES, SC BOGART, J BREIDENBACH, M CANDIA, A CLAUS, R CUTLER, H DAVIS, R DUBOIS, R FOSS, M FOX, J FOX, M GIOUMOUSIS, A GREBENYUK, A HALLER, G HAMILTON, V HODGSON, J HUFFER, M JUNK, T KIM, P LABS, J NEAL, H NELSON, D NORDBY, M PAFFRATH, L PUTALLAZ, G ROGERS, H RUSSELL, JJ SAEZ, P SEWARD, P SHERDEN, D SKARPAAS, K SCHINDLER, RH WAITE, AP WATT, R BRAU, J BUGG, B WEIDEMANN, A GURD, D ORAM, C ASTBURY, A BEER, G CROSS, G HODGES, T HONMA, A KEELER, R LANGSTAFF, R MASON, G POFFENBERGER, P ROBERTSON, L SCHENK, P TURCOT, A TURCOTTE, M COOK, V FORBUSH, D HARRISON, J KIM, H JI, M MOCKETT, P TOEVS, F VELLA, E AF AXEN, D BOUGEROLLE, S SOBIE, R EIGEN, G DEJONGH, F HITLIN, D KELSEY, M KLEIN, M MINCER, A WISNIEWSKI, W WOLF, R ARROYO, C AU, Y BALTAY, C BOLTON, T BAZARKO, A CAMILLERI, L HYATT, E MANLY, S RABINOWITZ, S ROWSON, PC SELIGMAN, S SHAEVITZ, MH SMITH, S STEINER, RV ABT, I ALZOFON, D ARNETT, D BARRERA, F BELL, R BES, SC BOGART, J BREIDENBACH, M CANDIA, A CLAUS, R CUTLER, H DAVIS, R DUBOIS, R FOSS, M FOX, J FOX, M GIOUMOUSIS, A GREBENYUK, A HALLER, G HAMILTON, V HODGSON, J HUFFER, M JUNK, T KIM, P LABS, J NEAL, H NELSON, D NORDBY, M PAFFRATH, L PUTALLAZ, G ROGERS, H RUSSELL, JJ SAEZ, P SEWARD, P SHERDEN, D SKARPAAS, K SCHINDLER, RH WAITE, AP WATT, R BRAU, J BUGG, B WEIDEMANN, A GURD, D ORAM, C ASTBURY, A BEER, G CROSS, G HODGES, T HONMA, A KEELER, R LANGSTAFF, R MASON, G POFFENBERGER, P ROBERTSON, L SCHENK, P TURCOT, A TURCOTTE, M COOK, V FORBUSH, D HARRISON, J KIM, H JI, M MOCKETT, P TOEVS, F VELLA, E TI THE LEAD LIQUID ARGON SAMPLING CALORIMETER OF THE SLD DETECTOR SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID SYSTEM; IRON; PERFORMANCE; LUMINOSITY; URANIUM AB The lead-liquid argon sampling calorimeter of the SLD detector is one of the largest detectors employing cryogenic liquids now in operation. This paper details the design and performance considerations, the mechanical and cryogenic systems, the absorber design and tower segmentation, the data acquisition electronics, and the control systems of the detector. The initial operational performance of the device is discussed. Detailed resolution studies will be presented in a later paper. C1 UNIV BRITISH COLUMBIA,VANCOUVER V6T 2A6,BC,CANADA. CALTECH,PASADENA,CA 91125. COLUMBIA UNIV,NEVIS LAB,IRVINGTON,NY 10533. STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. UNIV TENNESSEE,KNOXVILLE,TN 37996. TRIUMF,VANCOUVER V6T 2A3,BC,CANADA. UNIV VICTORIA,VICTORIA V8W 2Y2,BC,CANADA. UNIV WASHINGTON,SEATTLE,WA 98195. RI Cross, Graham/B-9447-2008 OI Cross, Graham/0000-0003-2299-6091 NR 18 TC 30 Z9 30 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1993 VL 328 IS 3 BP 472 EP 494 DI 10.1016/0168-9002(93)90664-4 PG 23 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ090 UT WOS:A1993KZ09000009 ER PT J AU ALEXANDREAS, DE BERLEY, D BILLER, S DION, GM GOODMAN, JA HAINES, TJ HOFFMAN, CM HORCH, E LU, XQ SINNIS, C YODH, GB ZHANG, W AF ALEXANDREAS, DE BERLEY, D BILLER, S DION, GM GOODMAN, JA HAINES, TJ HOFFMAN, CM HORCH, E LU, XQ SINNIS, C YODH, GB ZHANG, W TI POINT-SOURCE SEARCH TECHNIQUES IN ULTRA-HIGH ENERGY GAMMA-RAY ASTRONOMY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB Searches for point astrophysical sources of ultra high energy (UHE) gamma rays are plagued by large numbers of background events from isotropic cosmic rays. Some of the methods that have been used to estimate the expected number of background events coming from the direction of a possible source are found to contain biases. Search techniques that avoid this problem are described. There is also a discussion of how to optimize the sensitivity of a search to emission from a point source. C1 NATL SCI FDN,WASHINGTON,DC 20550. UNIV CALIF IRVINE,DEPT PHYS,IRVINE,CA 92717. UNIV MARYLAND,DEPT PHYS,COLL PK,MD 20742. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. NR 15 TC 77 Z9 77 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 MAY 1 PY 1993 VL 328 IS 3 BP 570 EP 577 DI 10.1016/0168-9002(93)90677-A PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ090 UT WOS:A1993KZ09000022 ER PT J AU GRUEN, DM AF GRUEN, DM TI C-60 INTERACTIONS WITH SURFACES, GASEOUS SPECIES AND PHOTONS - AN OVERVIEW SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL WORKSHOP ON INELASTIC ION-SURFACE COLLISIONS ( IISC-9 ) CY SEP 14-18, 1992 CL AUSSOIS, FRANCE SP EUROPEAN PHYS SOC, MINIST RECH ESPACE FRANCE, MINIST EDUC NATL FRANCE, CNRS, DIRECT ETUDE TECH ID CARBON CLUSTER IONS; GAS-PHASE; UNIMOLECULAR DECAY; COVALENT CLUSTERS; SMALL PARTICLES; EVAPORATION; IONIZATION; C-60; C70; FULLERENES AB The behavior of C60 in collisions with surfaces, with other gaseous species, and with photons is discussed. The focus is on the processes leading to fragmentation of the molecule, the identification of fragmentation products, and the mechanism of fragmentation. The nature of the fragmentation process of C60 is of considerable interest in itself and needs to be understood in detail if C60 cluster ion beams are to be fully exploited technologically. In addition, one may anticipate that an understanding of C60 fragmentation will contribute mutatis mutandis to an elucidation of the elementary steps leading to the assembly of C60 from smaller carbon clusters. C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. RP GRUEN, DM (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. NR 52 TC 25 Z9 25 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1993 VL 78 IS 1-4 BP 118 EP 125 DI 10.1016/0168-583X(93)95787-6 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA LE969 UT WOS:A1993LE96900020 ER PT J AU HEIKKINEN, DW BENCH, GS ANTOLAK, AJ MORSE, DH PONTAU, AE AF HEIKKINEN, DW BENCH, GS ANTOLAK, AJ MORSE, DH PONTAU, AE TI THE LLNL MULTIUSER TANDEM LABORATORY PIXE MICROPROBE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON NUCLEAR MICROPROBE TECHNOLOGY AND APPLICATIONS CY JUN 08-12, 1992 CL UPPSALA, SWEDEN SP WENNER GREN CTR FDN SCI RES, NAT SCI RES COUNCIL, ELEMENTIS VITAE FDN MED RES, HASSLO VINMAKARE, UPPSALA UNIV, DEPT RADIAT SCI AB We have recently completed the construction of a new ion beamline primarily for particle-induced X-ray emission (PIXE) analysis. This will supplement our current ion microtomography (IMT) material characterization capabilities using accelerator microanalysis. In this paper we describe the PIXE beamline and give some results that characterize the system. We also report the results of some initial experiments. C1 SANDIA NATL LABS,LIVERMORE,CA 94551. RP HEIKKINEN, DW (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551, USA. NR 5 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1993 VL 77 IS 1-4 BP 45 EP 48 DI 10.1016/0168-583X(93)95521-6 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ782 UT WOS:A1993KZ78200009 ER PT J AU MARSH, EP STRATHMAN, MD REED, DA MORSE, DH PONTAU, AE ODOM, RW AF MARSH, EP STRATHMAN, MD REED, DA MORSE, DH PONTAU, AE ODOM, RW TI HIGH-RESOLUTION, POSITION-SENSITIVE DETECTOR FOR ENERGETIC PARTICLE BEAMS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON NUCLEAR MICROPROBE TECHNOLOGY AND APPLICATIONS CY JUN 08-12, 1992 CL UPPSALA, SWEDEN SP WENNER GREN CTR FDN SCI RES, NAT SCI RES COUNCIL, ELEMENTIS VITAE FDN MED RES, HASSLO VINMAKARE, UPPSALA UNIV, DEPT RADIAT SCI AB The performance and design of an imaging position sensitive, particle beam detector will be presented. The detector is minimally invasive, operates over a wide dynamic range (> 10(10)), and exhibits high spatial resolution. The secondary electrons produced when a particle beam passes through a thin foil are imaged using stigmatic ion optics onto a two-dimensional imaging detector. Due to the low scattering cross section of the 6 nm carbon foil the detector is a minimal perturbation on the primary beam. A prototype detector with an image resolution of approximately 5 mum for a field of view of 1 mm has been reported [R.W. Odom, M.D. Strathman, S.E. Buttrill, Jr., and S.M. Bauman, Nucl. Instr. and Meth. B44 (1990) 465]. A higher resolution detector for imaging small beams ( < 50 mum) with an image resolution of better than 0.5 mum has since been developed and its design is presented. C1 SANDIA NATL LABS,LIVERMORE,CA 94550. RP MARSH, EP (reprint author), CHARLES EVANS & ASSOCIATES,REDWOOD CITY,CA, USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1993 VL 77 IS 1-4 BP 85 EP 91 DI 10.1016/0168-583X(93)95529-E PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ782 UT WOS:A1993KZ78200017 ER PT J AU ROBERTS, ML HEIKKINEN, DW PROCTOR, ID PONTAU, AE OLONA, GT FELTER, TE MORSE, DH HESS, BV AF ROBERTS, ML HEIKKINEN, DW PROCTOR, ID PONTAU, AE OLONA, GT FELTER, TE MORSE, DH HESS, BV TI ION MICROTOMOGRAPHY USING ION TIME-OF-FLIGHT SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON NUCLEAR MICROPROBE TECHNOLOGY AND APPLICATIONS CY JUN 08-12, 1992 CL UPPSALA, SWEDEN SP WENNER GREN CTR FDN SCI RES, NAT SCI RES COUNCIL, ELEMENTIS VITAE FDN MED RES, HASSLO VINMAKARE, UPPSALA UNIV, DEPT RADIAT SCI ID DETECTOR AB We have developed and are in the process of testing an ion time-of-flight (TOF) detector system for use in our ion microtomography measurements. Using TOF, ion energy is determined by measurement of the ion's flight time over a certain path length. For ion microtomography, the principle advantage of TOF analysis is that ion count rates of several hundred thousand counts per second can be achieved as compared to a limit of about ten thousand ions per second when using a solid-state silicon surface barrier detector and associated electronics. This greater than 10-fold increase in count rate correspondingly shortens sample analysis time or increases the amount of data that can be collected on a given sample. C1 SANDIA NATL LABS,LIVERMORE,CA 94551. RP ROBERTS, ML (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551, USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1993 VL 77 IS 1-4 BP 225 EP 228 DI 10.1016/0168-583X(93)95547-I PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ782 UT WOS:A1993KZ78200035 ER PT J AU STUART, SA CHOLEWA, M SAINT, A PRAWER, S LEGGE, GJF WEIRUP, D AF STUART, SA CHOLEWA, M SAINT, A PRAWER, S LEGGE, GJF WEIRUP, D TI INVESTIGATION OF ISOLATED CHEMICAL-VAPOR-DEPOSITED DIAMONDS USING STIM TOMOGRAPHY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON NUCLEAR MICROPROBE TECHNOLOGY AND APPLICATIONS CY JUN 08-12, 1992 CL UPPSALA, SWEDEN SP WENNER GREN CTR FDN SCI RES, NAT SCI RES COUNCIL, ELEMENTIS VITAE FDN MED RES, HASSLO VINMAKARE, UPPSALA UNIV, DEPT RADIAT SCI ID FILMS AB In order to understand the growth mechanisms of chemical vapour deposited (CVD) diamonds, and ultimately improve the quality of CVD diamond films, isolated crystals rather than polycrystalline films should be studied. In polycrystalline film, grain boundaries, overgrowth and secondary nucleation are sources of defects and nondiamond components, which reduce the quality of the films and hence drastically limit the commercial applications. Isolated diamond crystals were grown on the end of tungsten wire tips by Microwave Plasma CVD. In an attempt to study the nature of growth of crystals, STIM (scanning transmission ion microscopy) tomography was used to map density variations within the formed diamond particles. C1 UNIV MELBOURNE,SCH PHYS,MARC,PARKVILLE,VIC 3052,AUSTRALIA. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. INST NUCL PHYS,PL-31342 KRAKOW,POLAND. RP STUART, SA (reprint author), RMIT,DEPT APPL PHYS,GPO BOX 2476V,MELBOURNE,VIC 3001,AUSTRALIA. RI Cholewa, Marian/C-9474-2011 NR 6 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1993 VL 77 IS 1-4 BP 234 EP 238 DI 10.1016/0168-583X(93)95549-K PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ782 UT WOS:A1993KZ78200037 ER PT J AU HORN, KM DOYLE, BL SEXTON, FW LAIRD, JS SAINT, A CHOLEWA, M LEGGE, GJF AF HORN, KM DOYLE, BL SEXTON, FW LAIRD, JS SAINT, A CHOLEWA, M LEGGE, GJF TI ION-BEAM-INDUCED CHARGE COLLECTION (IBICC) MICROSCOPY OF ICS - RELATION TO SINGLE EVENT UPSETS (SEU) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON NUCLEAR MICROPROBE TECHNOLOGY AND APPLICATIONS CY JUN 08-12, 1992 CL UPPSALA, SWEDEN SP WENNER GREN CTR FDN SCI RES, NAT SCI RES COUNCIL, ELEMENTIS VITAE FDN MED RES, HASSLO VINMAKARE, UPPSALA UNIV, DEPT RADIAT SCI ID CIRCUITS AB Single event upset (SEU) imaging is a new diagnostic technique recently developed using Sandia's nuclear microprobe. This technique directly images, with micron resolution, those regions within an integrated circuit which are susceptible to ion-induced malfunctions. Such malfunctions are an increasing threat to space-based systems which make use of current-generation IC designs. A complementary technique to SEU imaging involves measurement of the charge collection volumes within integrated circuits; charge collection is the underlying physical process responsible for single event phenomena. This technique, which we term ion beam induced charge collection (IBICC), has been used here and elsewhere to generate micron resolution maps of the charge collection response of integrated circuits. In this paper, we demonstrate the utility of combining the SEU imaging and IBICC techniques in order to gain a better understanding of single event upset phenomena. High resolution IBICC images are used to extract more detailed information from charge collection spectra than that obtained from conventional broad-area ion exposures, such as from radioactive sources. Lastly, we suggest the application of IBICC as a replacement for electron beam induced conduction/current (EBIC) measurements. As reductions in circuit feature size continue in the submicron regime, IBICC could certainly prove to be a technologically valuable replacement for EBIC and an important business opportunity for all nuclear microprobe facilities. C1 UNIV MELBOURNE,MARC,PARKVILLE,VIC 3052,AUSTRALIA. RP HORN, KM (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. RI Cholewa, Marian/C-9474-2011 NR 13 TC 30 Z9 30 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1993 VL 77 IS 1-4 BP 355 EP 361 DI 10.1016/0168-583X(93)95566-N PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA KZ782 UT WOS:A1993KZ78200054 ER PT J AU TARTAGLIA, MA AF TARTAGLIA, MA TI THE E/PI-RATIOS AND PI(0)/PI-RATIOS MEASURED, AND MONOCHROMATIC GAMMA-BEAMS AND PI(0)-BEAMS EXPLORED IN THE D0 TEST CALORIMETER SO NUCLEAR PHYSICS B LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON ADVANCED TECHNOLOGY AND PARTICLE PHYSICS CY JUN 22-26, 1992 CL COMO, ITALY SP IST NAZL FIS NUCL, UNIV FLORENCE ID LIQUID ARGON CALORIMETER; ELECTRON RESPONSE; HADRON AB The e/pi response ratio of the DO end calorimeter has been measured by comparing data from 10 to 150 GeV/c electron and pion beams. The ''intrinsic'' e/pi of the fine-hadronic module has also been studied with the pions alone, by selecting pi0-like showers contained within individual layers of the calorimeter. The measurements are compared to GEANT Monte Carlo simulations. A technique to generate monochromatic test beams of photons and neutral pions was successfully investigated. Preliminary results from central calorimeter modules exposed to these beams are discussed, and are compared to calculated expectations. RP TARTAGLIA, MA (reprint author), FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. NR 11 TC 0 Z9 0 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 MAY PY 1993 SU 32 BP 83 EP 90 PG 8 WC Physics, Particles & Fields SC Physics GA LF473 UT WOS:A1993LF47300010 ER PT J AU ADRIANI, O AHLEN, S AMBROSI, G BABUCCI, E BARBAGLI, G BASCHIROTTO, A BATTISTON, R BAY, A BENCZE, G BENE, P BERTUCCI, B BIASINI, M BILEI, G BOISSEVAIN, JG BOSETTI, M BROOKS, ML BUSENITZ, J BURGER, WJ CAMPS, C CARIA, M CASTELLINI, G CASTELLO, R CHECCUCCI, B CHEN, A CHEN, WY COAN, TE COMMICHAU, V DIBITONTO, D EASO, S EXTERMANN, P FIANDRINI, E GOUGAS, A HANGARTER, K HAUVILLER, C HERVE, A HOFER, H KAPUSTINSKI, JS KINNISON, WW KIRST, H KRASTEV, VR LANDI, G LEBEAU, M LECOQ, P LEE, DM LEISTE, R LIN, W LOHMANN, W LUBELSMEYER, K MACDERMOTT, M MARIN, A MASCIOCCHI, F MATAY, G MILLER, GB MILLS, G NOWAK, H PASSALEVA, G PENNINGTON, T PAUL, T PAULUZZI, M PENSOTTI, S PERRIN, E RANCOITA, PG RATTAGGI, M RICHEUX, JP SANTOCCHIA, A SACHWITZ, M SCHMITZ, P SCHONEICH, B SERVOLI, L SIEDLING, R SUBHANI, K TERZI, G THOMPSON, TC TONISCH, F TROWITZSCH, G VIERTEL, GM VOGT, H WALDMEIER, S WANG, S WEILL, R YEH, SC ZHOU, B AF ADRIANI, O AHLEN, S AMBROSI, G BABUCCI, E BARBAGLI, G BASCHIROTTO, A BATTISTON, R BAY, A BENCZE, G BENE, P BERTUCCI, B BIASINI, M BILEI, G BOISSEVAIN, JG BOSETTI, M BROOKS, ML BUSENITZ, J BURGER, WJ CAMPS, C CARIA, M CASTELLINI, G CASTELLO, R CHECCUCCI, B CHEN, A CHEN, WY COAN, TE COMMICHAU, V DIBITONTO, D EASO, S EXTERMANN, P FIANDRINI, E GOUGAS, A HANGARTER, K HAUVILLER, C HERVE, A HOFER, H KAPUSTINSKI, JS KINNISON, WW KIRST, H KRASTEV, VR LANDI, G LEBEAU, M LECOQ, P LEE, DM LEISTE, R LIN, W LOHMANN, W LUBELSMEYER, K MACDERMOTT, M MARIN, A MASCIOCCHI, F MATAY, G MILLER, GB MILLS, G NOWAK, H PASSALEVA, G PENNINGTON, T PAUL, T PAULUZZI, M PENSOTTI, S PERRIN, E RANCOITA, PG RATTAGGI, M RICHEUX, JP SANTOCCHIA, A SACHWITZ, M SCHMITZ, P SCHONEICH, B SERVOLI, L SIEDLING, R SUBHANI, K TERZI, G THOMPSON, TC TONISCH, F TROWITZSCH, G VIERTEL, GM VOGT, H WALDMEIER, S WANG, S WEILL, R YEH, SC ZHOU, B TI STATUS OF THE L3 SILICON MICROVERTEX DETECTOR SO NUCLEAR PHYSICS B LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON ADVANCED TECHNOLOGY AND PARTICLE PHYSICS CY JUN 22-26, 1992 CL COMO, ITALY SP IST NAZL FIS NUCL, UNIV FLORENCE ID DISPLACEMENT-MEASURING SYSTEM AB A report on the status of the construction of the L3 Silicon Microvertex Detector is presented here. The detector will consist of two double sided AC coupled silicon layers equipped with rphi and z readout with an expected intrinsic resolution of almost-equal-to 6 mum and almost-equal-to 25 mum respectively. A description of the detector with its mechanical support, alignment system and readout electronics is presented. C1 RHEIN WESTFAL TH AACHEN,INST PHYS 3,W-5100 AACHEN,GERMANY. UNIV ALABAMA,TUSCALOOSA,AL 35401. BOSTON UNIV,BOSTON,MA 02215. CERN,EUROPEAN LAB PARTICLE PHYS,CH-1211 GENEVA 23,SWITZERLAND. INFN,FLORENCE,ITALY. UNIV FLORENCE,I-50121 FLORENCE,ITALY. IST RIC ONDE ELETTROMAGNET,FLORENCE,ITALY. JOHNS HOPKINS UNIV,BALTIMORE,MD 21218. UNIV GENEVA,CH-1211 GENEVA 4,SWITZERLAND. UNIV LAUSANNE,CH-1000 LAUSANNE 17,SWITZERLAND. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. INFN,MILAN,ITALY. INFN,PERUGIA,ITALY. NATL CENT UNIV CHUNG LI,CHUNGLI,TAIWAN. UNIV PERUGIA,I-06100 PERUGIA,ITALY. DESY IFH,ZEUTHEN,GERMANY. SWISS FED INST TECHNOL,CH-8092 ZURICH,SWITZERLAND. NATL TSING HUA UNIV,HSINCHU 300,TAIWAN. RP ADRIANI, O (reprint author), RHEIN WESTFAL TH AACHEN,INST PHYS 1,W-5100 AACHEN,GERMANY. RI Fiandrini, Emanuele/C-4549-2008; Servoli, Leonello/E-6766-2012; bertucci, bruna/J-5237-2012; Rancoita, Pier Giorgio/J-9896-2015; OI Servoli, Leonello/0000-0003-1725-9185; Rancoita, Pier Giorgio/0000-0002-1990-4283; Ambrosi, Giovanni/0000-0001-6977-9559; Castellini, Guido/0000-0002-0177-0643; Bertucci, Bruna/0000-0001-7584-293X NR 14 TC 11 Z9 11 U1 0 U2 1 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 MAY PY 1993 SU 32 BP 202 EP 207 DI 10.1016/0920-5632(93)90025-2 PG 6 WC Physics, Particles & Fields SC Physics GA LF473 UT WOS:A1993LF47300023 ER PT J AU PEREZMENDEZ, V CHO, G DREWERY, J JING, T KAPLAN, SN MIRESHGHI, A WILDERMUTH, D GOODMAN, C FUJIEDA, I AF PEREZMENDEZ, V CHO, G DREWERY, J JING, T KAPLAN, SN MIRESHGHI, A WILDERMUTH, D GOODMAN, C FUJIEDA, I TI AMORPHOUS-SILICON PIXEL RADIATION DETECTORS AND ASSOCIATED THIN-FILM-TRANSISTOR ELECTRONICS READOUT SO NUCLEAR PHYSICS B LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON ADVANCED TECHNOLOGY AND PARTICLE PHYSICS CY JUN 22-26, 1992 CL COMO, ITALY SP IST NAZL FIS NUCL, UNIV FLORENCE ID LAYERS AB We describe the characteristics of thin (1 mum) and thick (> 30 mum) hydrogenated amorphous silicon p-i-n diodes which are optimized for detecting and recording the spatial distribution of charged particles, x-rays, gamma rays and thermal neutrons. For x-ray, gamma ray, and charged particle detection we can use thin p-i-n photosensitive diode arrays coupled to evaporated layers of suitable scintillators. For thermal neutron detection we use thin (2-5 mum) gadolinium converters on 30 mum thick a-Si:H diodes. For direct detection of minimum ionizing particles and others with high resistance to radiation damage, we use the thick p-i-n diode arrays. Diode and amorphous silicon readouts as well as polysilicon pixel amplifiers are described. C1 AIR TECH CORP,HICKSVILLE,NY 11801. NEC CORP LTD,KAWASAKI,KANAGAWA 213,JAPAN. RP PEREZMENDEZ, V (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. RI Cho, Gyuseong/C-1527-2011 NR 19 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 MAY PY 1993 SU 32 BP 287 EP 295 DI 10.1016/0920-5632(93)90036-6 PG 9 WC Physics, Particles & Fields SC Physics GA LF473 UT WOS:A1993LF47300034 ER PT J AU AMOS, NA ANDERSON, DF AF AMOS, NA ANDERSON, DF TI ADDITION OF PHOTOSENSITIVE DOPANTS TO THE D0 LIQUID ARGON CALORIMETER SO NUCLEAR PHYSICS B LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON ADVANCED TECHNOLOGY AND PARTICLE PHYSICS CY JUN 22-26, 1992 CL COMO, ITALY SP IST NAZL FIS NUCL, UNIV FLORENCE ID ELECTRON RESPONSE; HADRON AB The addition of photosensitive dopants to liquid argon greatly enhances the signal from heavily ionizing particles. Since binding energy losses are correlated with the heavily ionizing component in hadronic showers, the addition of photosensitive dopants has been suggested as a mechanism to tune the e/pi ratio in liquid argon calorimeters. A measurement was performed at the FNAL test beam, adding 4 ppm tetramethylgermanium to the DO uranium-liquid argon calorimeter. An increase in response for electromagnetic and hadronic showers was observed, with no net change in the e/pi ratio. RP AMOS, NA (reprint author), FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. NR 8 TC 0 Z9 0 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 MAY PY 1993 SU 32 BP 307 EP 313 PG 7 WC Physics, Particles & Fields SC Physics GA LF473 UT WOS:A1993LF47300037 ER PT J AU SANDERS, H CHEU, E ZELEZNIK, M HANSEN, S TSCHIRHART, R AF SANDERS, H CHEU, E ZELEZNIK, M HANSEN, S TSCHIRHART, R TI A MULTICORRELATED SAMPLER OF THE HIGH-RESOLUTION ACQUISITION-SYSTEM FOR HIGH-RATE FIXED TARGET KTEV EXPERIMENTS AT FERMILAB SO NUCLEAR PHYSICS B LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON ADVANCED TECHNOLOGY AND PARTICLE PHYSICS CY JUN 22-26, 1992 CL COMO, ITALY SP IST NAZL FIS NUCL, UNIV FLORENCE AB A new facility is being planned at Fermilab for fixed target experiments dealing with CP violation in rare neutral kaon decays; and precision measurements on the ''direct'' CP-violation parameters e'/e in the 2 pi decay mode of the neutral kaon system. This new Kaons at the TeVatron(KTeV) beam line is expected to be in operation in 1994. The most important new detector component in the KTeV spectrometer is the precision electromagnetic calorimeter, consisting of bars of Cesium Iodide crystals. The choice has been motivated by its radiation hardness, speed and light output. The size of this detector is 2 meters square and includes over 3200 blocks which are coupled to photomultipliers. We expect a peak anode current pulse of 100 ma from an 80 Gev deposit. The pulse shape approximates a signal with a FWHM of 25 nanoseconds, but contains some energy in a long tail that exists for more than 500 nanoseconds. The design for the data acquisition electronics will measure deposited charge in every channel in two 12 bit linear ranges: a low range of 2 MEV per count up to a maximum signal of 82 GEV and a range that will handle signals ten times larger with the same proportion in energy resolution. Since the total required dynamic range of this design is between 15 and 16 bit resolution, the problem of pedestal and pile up is seriously engaged with the configuration of this design. C1 FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. RP SANDERS, H (reprint author), UNIV CHICAGO,CHICAGO,IL 60637, USA. NR 0 TC 0 Z9 0 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 MAY PY 1993 SU 32 BP 333 EP 337 PG 5 WC Physics, Particles & Fields SC Physics GA LF473 UT WOS:A1993LF47300041 ER PT J AU LI, Z KRANER, HW AF LI, Z KRANER, HW TI MODELING AND SIMULATION OF CHARGE COLLECTION PROPERTIES FOR NEUTRON-IRRADIATED SILICON DETECTORS SO NUCLEAR PHYSICS B LA English DT Article ID RADIATION DETECTORS; DAMAGE AB Charge collection deficiencies for neutron irradiated silicon p+/n/n+ junction detectors are calculated from the interaction between the free carriers generated by particles to be detected and traps created by neutron radiation. The current induced on collection electrode as a function of time by free carriers moving in the detector electrical field is presented. Alpha (alpha) particle and minimum ionization particle (MIP) induced current shapes were simulated in various electrical field conditions including the reversal of the field in the case of ''type inversion''. The simulation based on alpha-particle data predicts that the charge collection deficiency of MIP for neutron damaged detector with the thickness of 350 mum after 1 x 10(14)n/cm2 would be less than 20 % when operated at a bias of 260 volts. RP BROOKHAVEN NATL LAB, UPTON, NY 11973 USA. NR 29 TC 25 Z9 25 U1 2 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1993 SU 32 BP 398 EP 409 DI 10.1016/0920-5632(93)90052-8 PG 12 WC Physics, Particles & Fields SC Physics GA LF473 UT WOS:A1993LF47300050 ER PT J AU KAPUSTINSKY, JS APOLINSKI, M BOISSEVAIN, J BROWN, CN BROWN, G CAREY, TA CHEN, YC CHILDERS, R COOPER, WE DARDEN, CW GIDAL, G GLASS, HD GOUNDER, KN HO, PM ISENHOWER, D JANSEN, DM JEPPESEN, R KAPLAN, DM KIANG, GC KOWITT, MS LANE, DW LEDERMAN, L LEITCH, MJ LILLBERG, JW LUEBKE, W LUK, KB MARTIN, VM MCGAUGHEY, PL MISHRA, CS MOSS, JM PENG, JC PRESTON, RS PRIPSTEIN, D SA, J SADLER, M SCHNATHORST, R SCHUB, MH SCHWINT, R SNODGRASS, D TANIKELLA, VN TENG, PK WILSON, JW AF KAPUSTINSKY, JS APOLINSKI, M BOISSEVAIN, J BROWN, CN BROWN, G CAREY, TA CHEN, YC CHILDERS, R COOPER, WE DARDEN, CW GIDAL, G GLASS, HD GOUNDER, KN HO, PM ISENHOWER, D JANSEN, DM JEPPESEN, R KAPLAN, DM KIANG, GC KOWITT, MS LANE, DW LEDERMAN, L LEITCH, MJ LILLBERG, JW LUEBKE, W LUK, KB MARTIN, VM MCGAUGHEY, PL MISHRA, CS MOSS, JM PENG, JC PRESTON, RS PRIPSTEIN, D SA, J SADLER, M SCHNATHORST, R SCHUB, MH SCHWINT, R SNODGRASS, D TANIKELLA, VN TENG, PK WILSON, JW TI RADIATION-DAMAGE EFFECTS ON THE SILICON MICROSTRIP DETECTOR IN E789 - A FIXED TARGET EXPERIMENT AT FERMILAB SO NUCLEAR PHYSICS B LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON ADVANCED TECHNOLOGY AND PARTICLE PHYSICS CY JUN 22-26, 1992 CL COMO, ITALY SP IST NAZL FIS NUCL, UNIV FLORENCE AB A Silicon Microstrip Spectrometer has been installed and successfully operated in experiment E789 at Fermilab. The main physics goal of the experiment is to search for charged particle decays of B and D Mesons. Damage effects due to ionizing radiation exposure to the silicon during the experiment are reported. C1 NO ILLINOIS UNIV,DE KALB,IL 60115. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. ACAD SINICA,TAIPEI 115,TAIWAN. NATL CHENG KUNG UNIV,TAINAN,TAIWAN. UNIV S CAROLINA,COLUMBIA,SC 29208. ABILENE CHRISTIAN UNIV,ABILENE,TX 79601. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CHICAGO,CHICAGO,IL 60637. RP KAPUSTINSKY, JS (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1993 SU 32 BP 425 EP 430 DI 10.1016/0920-5632(93)90055-B PG 6 WC Physics, Particles & Fields SC Physics GA LF473 UT WOS:A1993LF47300053 ER PT J AU WRIGHT, M MILLAUD, J NYGREN, D AF WRIGHT, M MILLAUD, J NYGREN, D TI A PIXEL UNIT-CELL TARGETING 16NS RESOLUTION AND RADIATION HARDNESS IN A COLUMN READ-OUT PARTICLE VERTEX DETECTOR SO NUCLEAR PHYSICS B LA English DT Article; Proceedings Paper CT 3RD INTERNATIONAL CONF ON ADVANCED TECHNOLOGY AND PARTICLE PHYSICS CY JUN 22-26, 1992 CL COMO, ITALY SP IST NAZL FIS NUCL, UNIV FLORENCE AB A pixel unit cell (PUC) circuit architecture, optimized for a column read out architecture, is reported. Each PUC contains an integrator, active filter, comparator, and optional analog store. The time-over-threshold (TOT) discriminator allows an all-digital interface to the array periphery readout while passing an analog measure of collected charge. Use of (existing) radiation hard processes, to build a detector bump-bonded to a pixel readout array, is targeted. Here emphasis is on a qualitative explanation of how the unique circuit implementation benefits operation for Super Collider (SSC) detector application. RP WRIGHT, M (reprint author), LAWRENCE BERKELEY LAB,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 18 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 MAY PY 1993 SU 32 BP 468 EP 479 DI 10.1016/0920-5632(93)90061-A PG 12 WC Physics, Particles & Fields SC Physics GA LF473 UT WOS:A1993LF47300059 ER PT J AU BORCHI, E FERBEL, T NYGREN, D PENZO, A RANCOITA, PG AF BORCHI, E FERBEL, T NYGREN, D PENZO, A RANCOITA, PG TI ADVANCED TECHNOLOGY AND PARTICLE PHYSICS - PROCEEDINGS OF THE 3RD INTERNATIONAL-CONFERENCE ON ADVANCED TECHNOLOGY AND PARTICLE PHYSICS - COMO, ITALY 22-26 JUNE 1992 - PREFACE SO NUCLEAR PHYSICS B LA English DT Editorial Material C1 INFN,FLORENCE,ITALY. INFN,TRIESTE,ITALY. UNIV ROCHESTER,ROCHESTER,NY 14627. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. INFN,MILAN,ITALY. RP BORCHI, E (reprint author), UNIV FLORENCE,I-50121 FLORENCE,ITALY. RI Rancoita, Pier Giorgio/J-9896-2015 OI Rancoita, Pier Giorgio/0000-0002-1990-4283 NR 0 TC 0 Z9 0 U1 0 U2 1 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 MAY PY 1993 SU 32 BP R5 EP R5 PG 1 WC Physics, Particles & Fields SC Physics GA LF473 UT WOS:A1993LF47300001 ER PT J AU CRAMER, SN SLATER, CO AF CRAMER, SN SLATER, CO TI INVESTIGATION OF RADIATION EFFECTS IN HIROSHIMA AND NAGASAKI USING A GENERAL MONTE-CARLO DISCRETE ORDINATES COUPLING SCHEME SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article AB A general Monte Carlo-discrete ordinates radiation transport coupling procedure has been created to study effects of the radiation environment in Hiroshima and Nagasaki due to the bombing of these two cities. The forward two-dimensional, free-field, air-over-ground flux is coupled with an adjoint Monte Carlo calculation. The size, orientation, or translation of the Monte Carlo geometry is unrestricted. The radiation effects calculated are the dose in the interior of a large concrete building in Nagasaki and the activation production of Co-60 and P-32 in Hiroshima. RP CRAMER, SN (reprint author), OAK RIDGE NATL LAB,POB 2008,OAK RIDGE,TN 37831, USA. NR 20 TC 3 Z9 3 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD MAY PY 1993 VL 114 IS 1 BP 1 EP 11 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA LA496 UT WOS:A1993LA49600001 ER PT J AU TAUTGES, TJ MOSES, GA CORRADINI, ML AF TAUTGES, TJ MOSES, GA CORRADINI, ML TI THE COMBINATION OF DATA AND FUNCTIONAL PARTITIONING TO PARALLELIZE SEVERE ACCIDENT COMPUTER CODES SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID SYSTEMS; RELAP5 AB Severe accident codes, i. e., codes that model core meltdown and accident progression in light water reactors, do not currently make use of parallel processing technology. Previous efforts to parallelize severe accident codes using DO-loop or data partitioning have resulted in speedup factors of <2.0 because of large serial code sections. Severe accident codes are more amenable to the functional partitioning approach, which splits a code into parallel tasks each representing a separate physical model. When combined, the two methods are able to partition 95% of the HECTR containment analysis code. Overall speedups of 2.6 and 3.2 on four and eight processors are obtained with the parallel HECTR code on an Alliant FX/80 parallel computer when modeling a moderately sized accident scenario. Speed ups are expected to increase for larger severe accident codes, such as MELCOR, which contain more functional parallelism than the HECTR code. C1 UNIV WISCONSIN,DEPT NUCL ENGN & ENGN PHYS,MADISON,WI 53706. RP TAUTGES, TJ (reprint author), SANDIA NATL LABS,DIV THERMAL HYDRAUL ANAL,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 16 TC 1 Z9 1 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD MAY PY 1993 VL 114 IS 1 BP 36 EP 41 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA LA496 UT WOS:A1993LA49600004 ER PT J AU LU, MS TEICHMANN, T AF LU, MS TEICHMANN, T TI ERROR PROPAGATION FOR GAMMA-SPECTROSCOPY AND NEUTRON COINCIDENCE COUNTING FOR PLUTONIUM-BEARING MATERIALS SO NUCLEAR TECHNOLOGY LA English DT Article DE ERROR PROPAGATION; HIGH-LEVEL NEUTRON COINCIDENCE COUNTING; HIGH-RESOLUTION GAMMA-RAY SPECTROSCOPY AB The error characteristics of both high-resolution gamma spectroscopy and high-level neutron coincidence (HLNC) measurements, separate or combined, are discussed as they apply to nondestructive analysis of plutonium-bearing materials. Expressions have been derived to estimate the overall variance in the Pu-240 effective mass and in the total plutonium mass in terms of the specific contributions from uncertainties in the measurements, the pertinent physical variables (including isotopics and impurities), and the instrumental constants. Experimental data available in the published literature have been used to illustrate the error characteristics of the HLNC and the effects of isotopic error correlations associated with materials having different burnups. RP LU, MS (reprint author), BROOKHAVEN NATL LAB,TECH SUPPORT ORG,UPTON,NY 11973, USA. NR 17 TC 2 Z9 2 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAY PY 1993 VL 102 IS 2 BP 196 EP 209 PG 14 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KY706 UT WOS:A1993KY70600005 ER PT J AU BARNER, JO CUNNINGHAM, ME FRESHLEY, MD LANNING, DD AF BARNER, JO CUNNINGHAM, ME FRESHLEY, MD LANNING, DD TI EVALUATION OF FISSION-GAS RELEASE IN HIGH-BURNUP LIGHT WATER-REACTOR FUEL-RODS SO NUCLEAR TECHNOLOGY LA English DT Article DE NUCLEAR FUEL; HIGH BURNUP; FISSION GAS RELEASE AB Research to define the behavior of Zircaloy-clad light water reactor (LWR) UO2 fuel irradiated to high burnup levels was conducted as part of the High Burnup Effects Program (HBEP). The HBEP was a 12-yr program that ultimately acquired, characterized, irradiated, and examined after irradiation 82 LWR fuel rods ranging in rod-average fuel burn up from 22 to 69 MWd/kg M with a peak pellet burnup of 83 MWd/kg M. A principal emphasis of the HBEP was to evaluate the effect of high burnup on fission gas release. It was confirmed that fission gas release remained as dependent on design and irradiation history parameters at high burnup levels as at low to moderate burnup levels. One observed high-burnup effect was the development of a burnup-dependent microstructure at the fuel pellet surface when pellet-edge burnup exceeded 65 MWd/kg M. This low-temperature ''rim region '' was characterized by a loss of optically definable grain structure, a high volume of porosity, and diffusion of fission gas from the UO2 matrix to the porosity. Although the rim region has the potential for enhanced fission gas release, it is concluded that no significant enhancement of rod-average fission gas release at high burnup levels was observed for the examined fuel rods. C1 PACIFIC NW LAB, LWR NPR TRITIUM TARGET DEV PROGRAM, RICHLAND, WA 99352 USA. RP BARNER, JO (reprint author), PACIFIC NW LAB, REACTOR SYST & MAT SECT, POB 999, RICHLAND, WA 99352 USA. NR 22 TC 8 Z9 8 U1 1 U2 3 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAY PY 1993 VL 102 IS 2 BP 210 EP 231 PG 22 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KY706 UT WOS:A1993KY70600006 ER PT J AU MACARTHUR, DW ALLANDER, KS BOUNDS, JA MCATEE, JL AF MACARTHUR, DW ALLANDER, KS BOUNDS, JA MCATEE, JL TI LRAD-BASED ALPHA-PARTICLE CONTAMINATION MONITORING OF PERSONNEL AND EQUIPMENT SO NUCLEAR TECHNOLOGY LA English DT Article DE ALPHA-PARTICLE DETECTOR; ALPHA-PARTICLE CONTAMINATION; CONTAMINATION MONITOR AB Traditional alpha-particle contamination monitors are limited in usefulness because of the short range of alpha particles in air. This range limitation makes it impossible to adequately monitor for alpha-particle contamination on uneven surfaces and inside equipment. Personnel must be scanned manually, a procedure that is comparatively uncertain. The long-range alpha detector eliminates many of the difficulties associated with equipment and personnel monitoring by detecting the ions produced by the alpha particles interaction with the air, rather than detecting the alpha particle itself. The personnel and equipment monitors are described in detail, and other potential applications are suggested. RP MACARTHUR, DW (reprint author), LOS ALAMOS NATL LAB,LONG RANGE ALPHA DETECTOR PROGRAM,LOS ALAMOS,NM 87545, USA. NR 6 TC 3 Z9 3 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAY PY 1993 VL 102 IS 2 BP 270 EP 276 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KY706 UT WOS:A1993KY70600010 ER PT J AU BIANCHI, AB FISCHER, SM ROBLES, AI RINCHIK, EM CONTI, CJ AF BIANCHI, AB FISCHER, SM ROBLES, AI RINCHIK, EM CONTI, CJ TI OVEREXPRESSION OF CYCLIN-D1 IN MOUSE SKIN CARCINOGENESIS SO ONCOGENE LA English DT Article ID CELL NUCLEAR ANTIGEN; HARVEY-RAS ONCOGENE; MESSENGER-RNA; CANDIDATE ONCOGENE; PAPILLOMAS; TUMORS; GENE; CARCINOMAS; MICE; HETEROZYGOSITY AB Recent studies have provided evidence suggesting that disruption of cyclin function may play a critical role in tumorigenesis. Cyclin D1, a putative G1 cyclin previously isolated in human parathyroid adenomas (designated PRAD1) and mouse macrophages (designated Cyl1), has been implicated in various neoplasias including breast and squamous cell carcinomas (SCC). The role of cyclin altered regulation in the different stages of tumor progression has not been studied in a well defined animal model system. In the study presented here, Cyl1 was mapped to the distal end of mouse chromosome 7 and found to be dramatically overexpressed in skin SCC. In premalignant stages of tumor development, early papillomas showed basal Cyl1 transcript levels, whereas overexpression was observed in most advanced papillomas. These findings suggest that altered expression of cyclin D1 plays a critical role in mouse skin carcinogenesis and may be related to the acquisition of autonomous growth by papillomas. Further studies on the role of cyclin D1 in the mouse model system should prove valuable for understanding the multistep basis of tumor progression. C1 UNIV TEXAS,MD ANDERSON CANC CTR,DEPT CARCINOGENESIS,DIV RES,SCI PK,POB 389,SMITHVILLE,TX 78957. OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. FU NCI NIH HHS [CA42157, CA53123] NR 47 TC 112 Z9 112 U1 1 U2 1 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE, HAMPSHIRE, ENGLAND RG21 6XS SN 0950-9232 J9 ONCOGENE JI Oncogene PD MAY PY 1993 VL 8 IS 5 BP 1127 EP 1133 PG 7 WC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity GA KY328 UT WOS:A1993KY32800003 PM 8479737 ER PT J AU RAUTMAN, CA REID, RA RYDER, EE AF RAUTMAN, CA REID, RA RYDER, EE TI SCHEDULING THE DISPOSAL OF NUCLEAR WASTE MATERIAL IN A GEOLOGIC REPOSITORY USING THE TRANSPORTATION MODEL SO OPERATIONS RESEARCH LA English DT Article AB An optimal disposal schedule for the burial of spent nuclear fuel from boiling-water and pressurized-water power reactors in a geologic repository has been developed using the classical transportation model from linear programming. Optimization is achieved by minimizing the total area required to absorb and dissipate the dynamic, yet highly predictable, quantity of heat produced by the nuclear waste. Costs associated with burying the spent power-reactor fuel can be measured in terms of the ''area required per ton of waste material.' This thermal cost is a time-varying quantity governed by the principles of radioactive decay. The resultant schedule provides for equivalent thermomechanical effects over the entire repository region following adjustments for the type and burnup level of the spent fuel while accommodating predetermined capacity specifications. C1 UNIV NEW MEXICO,ANDERSON SCH MANAGEMENT,ALBUQUERQUE,NM 87131. RP RAUTMAN, CA (reprint author), SANDIA NATL LABS,TECH STAFF,ALBUQUERQUE,NM 87185, USA. NR 9 TC 5 Z9 5 U1 0 U2 4 PU OPERATIONS RESEARCH SOC AMER PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2920 SN 0030-364X J9 OPER RES JI Oper. Res. PD MAY-JUN PY 1993 VL 41 IS 3 BP 459 EP 469 PG 11 WC Management; Operations Research & Management Science SC Business & Economics; Operations Research & Management Science GA LH377 UT WOS:A1993LH37700003 ER PT J AU AGGARWAL, A PARK, JK AF AGGARWAL, A PARK, JK TI IMPROVED ALGORITHMS FOR ECONOMIC LOT-SIZE PROBLEMS SO OPERATIONS RESEARCH LA English DT Article ID PLANNING-HORIZONS; MODEL; COMPLEXITY AB Many problems in inventory control, production planning, and capacity planning can be formulated in terms of a simple economic lot Size model Proposed independently by A. S. Manne (1958) and by H. M. Wagner and T. M. Whitin (1958). The Manne-Wagner-Whitin model and its variants have been studied widely in the operations research and management science communities, and a large number of algorithms have been proposed for solving various problems expressed in terms of this model, most of which assume concave costs and rely on dynamic programming. In this paper, we show that for many of these concave cost economic lot size problems, the dynamic programming formulation of the problem gives rise to a special kind of array, called a Monge array. We then show how the structure of Monge arrays can be exploited to obtain significantly faster algorithms for these economic lot size problems. We focus on uncapacitated problems, i.e., problems without bounds on production, inventory. or backlogging; capacitated problems are considered in a separate paper. C1 SANDIA NATL LABS,DEPT ALGORITHMS & DISCRETE MATH,SANDIA,NM. MIT,COMP SCI LAB,CAMBRIDGE,MA 02139. RP AGGARWAL, A (reprint author), IBM CORP,THOMAS J WATSON RES CTR,THEORET COMP SCI GRP,YORKTOWN HTS,NY 10598, USA. NR 47 TC 195 Z9 199 U1 5 U2 18 PU OPERATIONS RESEARCH SOC AMER PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2920 SN 0030-364X J9 OPER RES JI Oper. Res. PD MAY-JUN PY 1993 VL 41 IS 3 BP 549 EP 571 DI 10.1287/opre.41.3.549 PG 23 WC Management; Operations Research & Management Science SC Business & Economics; Operations Research & Management Science GA LH377 UT WOS:A1993LH37700009 ER PT J AU BAKER, JE AF BAKER, JE TI TERRAIN FOLLOWING AND MAPPING OF ARBITRARY SURFACES USING HIGH-PRECISION PROXIMITY DATA SO OPTICAL ENGINEERING LA English DT Article DE HIGH-PRECISION PROXIMITY SENSING; SURFACE MAPPING; SURFACE FOLLOWING AB Many mbotic operations, e.g., mapping, scanning, feature following, etc., require accurate surface following of arbitrary targets. A versatile surface-following and mapping system using a very high precision ''eye-in-hand'' proximity sensor, designed to provide hardware, software, and application independence, modular development, and up-ward expandability, is presented. These goals are met by a full a priori specification of the hardware and software interfaces; a modular system architecture; and a hierarchical surface-data analysis method, permitting application-specific tuning at each conceptual level of topological abstraction. This surface-following system was fully designed and implemented independent of any specific robotic host and then successfully integrated with and demonstrated on two very dissimilar real-time robotic systems. Presented in detail are the hardware and software architectures, the mapping and terrain forecasting algorithms, and the applications' environments and task requirements. RP BAKER, JE (reprint author), OAK RIDGE NATL LAB,CTR ENGN SYST ADV RES,AUTONOMOUS ROBOT GRP,INTELLIGENT SYST SECT,OAK RIDGE,TN 37831, USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SOC PHOTO-OPT INSTRUM ENG PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD MAY PY 1993 VL 32 IS 5 BP 1117 EP 1124 DI 10.1117/12.133328 PG 8 WC Optics SC Optics GA LA940 UT WOS:A1993LA94000033 ER PT J AU KRISHNAGOPAL, S SESSLER, AM AF KRISHNAGOPAL, S SESSLER, AM TI STABILITY OF RESONATOR CONFIGURATIONS IN THE PRESENCE OF FREE-ELECTRON LASER INTERACTIONS SO OPTICS COMMUNICATIONS LA English DT Article AB The stability of empty resonators (or cold cavities) has been widely studied, and is well understood. Here we consider the stability of symmetric resonator systems when there is a free-electron laser (FEL) interaction present within the cavity. We first construct a linear thick-lens model of the FEL and analytically study the dependence of resonator stability on its geometry. Next, we employ a nonlinear, three-dimensional FEL oscillator code to study the dependence of FEL performance on the cavity configuration The analytic and numerical approaches are compared and it is shown that they agree quite well. It is found that the region of stability is shifted toward longer cavities, and beyond the concentric configuration. Between the confocal and the concentric configurations, where the empty-resonator analysis predicts stability, there now appear regions of instability. We find that operation near the concentric configuration is preferable, and operation very near the confocal should be avoided. RP KRISHNAGOPAL, S (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD MAY 1 PY 1993 VL 98 IS 4-6 BP 274 EP 280 DI 10.1016/0030-4018(93)90195-B PG 7 WC Optics SC Optics GA KX536 UT WOS:A1993KX53600013 ER PT J AU VERNON, SP STEARNS, DG ROSEN, RS AF VERNON, SP STEARNS, DG ROSEN, RS TI CHIRPED MULTILAYER COATINGS FOR INCREASED X-RAY THROUGHPUT SO OPTICS LETTERS LA English DT Article ID MO; SI AB Chirped Mo-Si multilayer coatings, where the multilayer period is systematically varied throughout the deposition process, exhibit an increased x-ray bandwidth at normal incidence with a corresponding increase in the integrated reflectance of as much as 20% at lambda approximately 13 nm. The increased bandwidth is accompanied by a slight reduction in peak reflectance. The relation between the integrated and peak reflectance is used to determine the chirp required to optimize the x-ray throughput of a multiple-element optical system. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP VERNON, SP (reprint author), VERNON APPL PHYS,POB 10469,TORRANCE,CA 90505, USA. NR 6 TC 17 Z9 18 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAY 1 PY 1993 VL 18 IS 9 BP 672 EP 674 DI 10.1364/OL.18.000672 PG 3 WC Optics SC Optics GA KY942 UT WOS:A1993KY94200002 PM 19802235 ER PT J AU VU, BTV SZOKE, A LANDEN, OL AF VU, BTV SZOKE, A LANDEN, OL TI INDUCED FREQUENCY-SHIFTS BY COUNTERPROPAGATING SUBPICOSECOND OPTICAL PULSES SO OPTICS LETTERS LA English DT Article ID CROSS-PHASE MODULATION; STIMULATED RAMAN; FIBERS; SCATTERING; POWER AB We report time-resolved measurements of induced phase modulation that lead to frequency shifts in counter-propagating pump-probe experiments in a glass target with laser pulses of 0.7 ps FWHM and peak intensities of as high as 1 x 10(13) W/cm2. Experimental results can only be well explained by including, in addition to the shift induced during copropagation, a frequency shift proportional to the pump-pulse intensity profile during counterpropagation. This additional shift is shown to offer a new approach for mapping of temporal pulse profiles. The effects of pulse asymmetry are also examined. RP VU, BTV (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 20 TC 6 Z9 6 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAY 1 PY 1993 VL 18 IS 9 BP 723 EP 725 DI 10.1364/OL.18.000723 PG 3 WC Optics SC Optics GA KY942 UT WOS:A1993KY94200019 PM 19802252 ER PT J AU SCHAKE, AR AVENS, LR BURNS, CJ CLARK, DL SATTELBERGER, AP SMITH, WH AF SCHAKE, AR AVENS, LR BURNS, CJ CLARK, DL SATTELBERGER, AP SMITH, WH TI SYNTHESIS OF MIXED-RING ORGANOACTINIDE COMPLEXES .2. (C8H8)(C5ME5)U(THF) AND ITS 4,4'-DIMETHYL-2,2'-BIPYRIDINE DERIVATIVE SO ORGANOMETALLICS LA English DT Note ID TRIVALENT-URANIUM; CHEMISTRY; SANDWICH; LANTHANIDES; METAL AB The (pentamethylcyclopentadienyl)uranium-(III) complex (C5Me5)UI2(THF)3 reacts with K2C8H8 in THF to form the mixed-ring uranium(III) complex (C8H8)(C5Me5)U(THF) (1). Treatment of 1 with 4,4'-dimethyl-2,2'-bipyridine (Me2bpy) gives the 10-coordinate complex (C8H8)(C5Me5)U(Me2bPY) (2). The syntheses of 1 and 2 and the X-ray structure of 2 are described herein. C1 LOS ALAMOS NATL LAB,DIV ISOTOPE & NUCL CHEM,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,DIV NUCL MAT TECHNOL,LOS ALAMOS,NM 87545. RI Clark, David/A-9729-2011 NR 28 TC 46 Z9 46 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD MAY PY 1993 VL 12 IS 5 BP 1497 EP 1498 DI 10.1021/om00029a004 PG 2 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA LC841 UT WOS:A1993LC84100004 ER PT J AU ZANJANI, ED PIXLEY, JS SLOTNICK, N MACKINTOSH, FR EKHTERAE, D CLEMONS, G AF ZANJANI, ED PIXLEY, JS SLOTNICK, N MACKINTOSH, FR EKHTERAE, D CLEMONS, G TI ERYTHROPOIETIN DOES NOT CROSS THE PLACENTA INTO THE FETUS SO PATHOBIOLOGY LA English DT Article DE ERYTHROPOIETINS; PLACENTA; FETUS ID KIDNEY AB Erythropoiesis in the fetus is controlled by erythropoietin (Ep). To determine the role of maternal Ep in this process, we used catheterized preparations of sheep and monkey fetuses to assess the ability of Ep administered to the mother to cross the placental barrier into the fetus. Ep was injected into pregnant sheep (3,600 IU/sheep) or monkeys (800-2,000 IU/animal) as a single intravenous dose, or into sheep in intravenous doses of 2,000 IU once every 12 h for a total of 4 injections. Maternal and fetal blood samples for Ep and reticulocyte determinations were obtained before and at intervals after Ep injections. The administration of Ep resulted in significant increases in maternal circulating Ep levels in sheep and monkeys. Despite the presence of high levels of maternal Ep, however, no increase in fetal plasma Ep levels was detected. The administration of Ep to the mother caused significant increases in reticulocyte production in the mother but not the fetus; injection of Ep directly to the fetus stimulated fetal erythropoiesis. These results demonstrate that Ep does not cross the placenta into the fetus even under conditions of chronically elevated maternal Ep levels, and suggest that red cell production in the fetus is regulated by Ep produced from sites within the fetus. C1 UNIV CALIF DAVIS,DAVIS,CA 95616. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP ZANJANI, ED (reprint author), UNIV NEVADA,SCH MED,DEPT VET AFFAIRS MED CTR 151B,1000 LOCUST ST,RENO,NV 89520, USA. FU NHLBI NIH HHS [HL-46556, HL-49042, HL-40722] NR 12 TC 25 Z9 25 U1 0 U2 1 PU KARGER PI BASEL PA ALLSCHWILERSTRASSE 10, CH-4009 BASEL, SWITZERLAND SN 1015-2008 J9 PATHOBIOLOGY JI Pathobiology PD MAY-AUG PY 1993 VL 61 IS 3-4 BP 211 EP 215 DI 10.1159/000163796 PG 5 WC Cell Biology; Pathology SC Cell Biology; Pathology GA LZ085 UT WOS:A1993LZ08500013 PM 8216843 ER PT J AU HUELSKAMP, RM AF HUELSKAMP, RM TI PERSPECTIVES ON EDUCATION IN AMERICA SO PHI DELTA KAPPAN LA English DT Article RP HUELSKAMP, RM (reprint author), SANDIA NATL LABS,CTR STRATEG STUDIES,TECH STAFF,ALBUQUERQUE,NM 87185, USA. NR 0 TC 4 Z9 4 U1 0 U2 0 PU PHI DELTA KAPPA PI BLOOMINGTON PA 8TH AND UNION P O BOX 789, BLOOMINGTON, IN 47402 SN 0031-7217 J9 PHI DELTA KAPPAN JI Phi Delta Kappan PD MAY PY 1993 VL 74 IS 9 BP 718 EP 721 PG 4 WC Education & Educational Research SC Education & Educational Research GA LA434 UT WOS:A1993LA43400011 ER PT J AU ZHU, YM SUENAGA, M TAFTO, J AF ZHU, YM SUENAGA, M TAFTO, J TI THE INTERFACE OF ORTHOGONALLY ORIENTED TWINS IN YBA2CU3O7-DELTA SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID BOUNDARIES; CRYSTALS AB Twinning on the (110) and the equivalent (-110) planes is frequently encountered within one crystal grain in YBa2Cu3O7-delta. Using high-resolution electron microscopy and electron diffraction analysis, we studied the interface and its vicinity where the (110) and (-110) twins meet. We found that the crystal lattice of the impinging set of twins rotates around the c axis when they confront the orthogonally oriented twins. Every second one of the impinging twins is pointed, but does not taper off to zero width, yielding a small-angle grain boundary; the other twin forms a coherent boundary with a twin belonging to the orthogonal set. Thus, the interface of the orthogonally oriented twins comprises of an alternation of twin boundaries and grain boundaries. Furthermore, we found that there is a limiting wedge-angle for the tapered twins, and if this angle is exceeded, the tip of the twin splits. The structure of the interface and its vicinity is determined by the equilibrium of elastic strain energy due to the tetragonal orthorhombic phase transformation and the interfacial energy of the twin boundary and the grain boundary. The shape of the tapered twin was analysed based on the observed twinning dislocation and the associated twinning steps in YBa2Cu3O7-delta. RP ZHU, YM (reprint author), BROOKHAVEN NATL LAB,DIV MAT SCI,UPTON,NY 11973, USA. NR 27 TC 27 Z9 27 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 1993 VL 67 IS 5 BP 1057 EP 1069 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA LF723 UT WOS:A1993LF72300002 ER PT J AU MUTO, S MERK, N SCHRYVERS, D TANNER, LE AF MUTO, S MERK, N SCHRYVERS, D TANNER, LE TI DISPLACIVE REPLACIVE PHASE-TRANSFORMATION IN A NI62.5AL37.5 BETA-2-PHASE STUDIED BY HIGH-RESOLUTION ELECTRON-MICROSCOPY AND MICRODIFFRACTION SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID OMEGA PHASE; ALLOYS; DIFFRACTION; ANOMALIES; BETA AB The structure of the metastable Ni2Al phase, which has long been a matter of controversy, has been carefully re-examined by means of high-resolution transmission electron microscopy (HREM) and electron microdiffraction. First, it is concluded that theas-quenched NixAl100-x(60 less-than-or-equal-to x less-than-or-equal-to 65) material already exhibits a partial omega-type collapse in a one-dimensional fashion which and is consistent with the anomalous dip in the phonon dispersion curve. Ni2Al precipitates are formed on annealing by thermal decomposition of the high-temperature NixAl100-xB2 phase and still retain the small omega-type shuffle. The amount of displacement in the well developed Ni2Al phase was estimated to be between 20 and 50% of the ideal omega collapse; this was determined by means of a combined technique of HREM and microdiffraction together with dynamical calculations of HREM images and diffraction intensities. C1 LAWRENCE BERKELEY LAB,NATL CTR ELECTR MICROSCOPY,BERKELEY,CA 94720. LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,LIVERMORE,CA 94550. RP MUTO, S (reprint author), UNIV ANTWERP,GROENENBORGERLAAN 171,B-2020 ANTWERP,BELGIUM. RI Muto, Shunsuke/G-5741-2012 OI Muto, Shunsuke/0000-0001-6275-0649 NR 16 TC 16 Z9 16 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD MAY PY 1993 VL 67 IS 5 BP 673 EP 689 DI 10.1080/13642819308219316 PG 17 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA LF720 UT WOS:A1993LF72000005 ER PT J AU MALOY, SA MITCHELL, TE LEWANDOWSKI, JJ HEUER, AH AF MALOY, SA MITCHELL, TE LEWANDOWSKI, JJ HEUER, AH TI (103)(331) SLIP IN MOSI2 SO PHILOSOPHICAL MAGAZINE LETTERS LA English DT Article ID DEFORMATION AB {103}[331] slip is found to be activated in MoSi2 single crystals by deformation along [001] in uniaxial compression at 1000-degrees-C. The {103} slip plane has been determined by slip trace analysis. Observations by transmission electron microscopy reveal the presence of screw dislocations with a Burgers vector of 1/2[331]. However, 1/2[331] dislocations of mixed character lying along the [010] direction are observed to have decomposed into two other perfect dislocations by the energetically favourable reaction 1/2[331]-->1/2[111]+[110]. The occurrence of such dislocation decomposition explains the difficulty of observing 1/2[331] dislocations in previous work. The 1/2[331] screw dislocations have been examined by weak-beam dark-field microscopy but dissociation into three 1/6[331] collinear partials could not be detected. C1 CASE WESTERN RESERVE UNIV,DEPT MAT SCI & ENGN,CLEVELAND,OH 44106. RP MALOY, SA (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,LOS ALAMOS,NM 87545, USA. RI Maloy, Stuart/A-8672-2009 OI Maloy, Stuart/0000-0001-8037-1319 NR 16 TC 18 Z9 18 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0950-0839 J9 PHIL MAG LETT JI Philos. Mag. Lett. PD MAY PY 1993 VL 67 IS 5 BP 313 EP 321 DI 10.1080/09500839308241268 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA LF715 UT WOS:A1993LF71500002 ER PT J AU HUBER, G ALSTROM, P AF HUBER, G ALSTROM, P TI UNIVERSAL DECAY OF VORTEX DENSITY IN 2 DIMENSIONS SO PHYSICA A LA English DT Article ID 2-DIMENSIONAL TURBULENCE; DYNAMICS; ANNIHILATION; SYSTEM; MODEL AB Recent numerical and experimental results for freely decaying two-dimensional turbulence point to a universal decay in vortex density, rho approximately t(-xi) (xi congruent-to 0.73), from highly turbulent to laminar, vortex-free flows. This vortex decay has been successfully described in terms of a point-vortex dynamics, in close resemblance to the vortex dynamics for the two-dimensional Ginzburg-Landau equation. Here, we add numerical evidence and give theoretical arguments that the vortex density at late times follows the conjectured power law with xi = 3/4. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. NIELS BOHR INST,ORSTED LAB,DK-2100 COPENHAGEN 0,DENMARK. RP HUBER, G (reprint author), BOSTON UNIV,CTR POLYMER STUDIES,BOSTON,MA 02215, USA. NR 19 TC 22 Z9 22 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD MAY 1 PY 1993 VL 195 IS 3-4 BP 448 EP 456 DI 10.1016/0378-4371(93)90169-5 PG 9 WC Physics, Multidisciplinary SC Physics GA LB861 UT WOS:A1993LB86100012 ER PT J AU JOYCE, JJ ARKO, AJ RISEBOROUGH, PS CANFIELD, PC LAWRENCE, JM BLYTH, RIR BARTLETT, RJ THOMPSON, JD FISK, Z AF JOYCE, JJ ARKO, AJ RISEBOROUGH, PS CANFIELD, PC LAWRENCE, JM BLYTH, RIR BARTLETT, RJ THOMPSON, JD FISK, Z TI PHOTOEMISSION AND THE KONDO MODEL - SERIOUS DISCREPANCIES BETWEEN THEORY AND EXPERIMENT IN HEAVY-FERMION SYSTEMS SO PHYSICA B-CONDENSED MATTER LA English DT Article ID ELECTRONIC-STRUCTURE; EXCITATIONS; RESONANCE; SPECTRA; CERIUM; YBXCU4; CESI2; CE AB Resonant photoelectron spectroscopy has been used to examine the electronic structure of Ce- and Yb-based heavy fermions. The experimental results are compared with Gunnarsson-Schonhammer calculations which include crystal field and finite U(ff) effects. Comparison of the model and experimental results reveals a large disparity between predictions and actual results. In particular, the Kondo model predictions of width, energy position and spectral weight for features near the Fermi level are not realized. Additionally, there is disparity between calculation and photoemission data in the Fermi-level crossing positions for spectral features very near the Fermi level. These discrepancies are present for both Ce and Yb heavy fermion systems. We see no evidence of spectral features in the photoemission data which can be uniquely identified with the Kondo resonance while our calculations show the resolution is adequate to clearly distinguish such features. C1 POLYTECH INST NEW YORK, DEPT PHYS, BROOKLYN, NY 11201 USA. UNIV CALIF IRVINE, DEPT PHYS, IRVINE, CA 92717 USA. RP JOYCE, JJ (reprint author), LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87454 USA. RI Riseborough, Peter/D-4689-2011; Canfield, Paul/H-2698-2014 NR 31 TC 16 Z9 16 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 31 EP 37 DI 10.1016/0921-4526(93)90488-R PG 7 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400007 ER PT J AU CHO, EJ OH, SJ OLSON, CG KANG, JS ANDERSON, RO LIU, LZ PARK, JH ALLEN, JW AF CHO, EJ OH, SJ OLSON, CG KANG, JS ANDERSON, RO LIU, LZ PARK, JH ALLEN, JW TI HIGH-RESOLUTION PHOTOEMISSION-STUDY OF YBAL3 AT LOW-TEMPERATURE SO PHYSICA B-CONDENSED MATTER LA English DT Article AB The valence upsilon and the 4f14 --> 4f7/4(13) transition energy T(K) of YbAl3 at low temperature were determined by the high resolution valence band photoemission spectroscopy. The obtained values upsilon = 2.65 +/- 0.03 and T(K) = 30 +/- 15 meV are consistent with the zero-temperature magnetic susceptibility chi(m)(0), supporting the Anderson Hamiltonian description for its electronic structure. C1 SEOUL NATL UNIV, DEPT PHYS, SEOUL 151742, SOUTH KOREA. IOWA STATE UNIV SCI & TECHNOL, AMES LAB, AMES, IA 50011 USA. RES INST IND SCI & TECHNOL, POHANG 790600, SOUTH KOREA. UNIV MICHIGAN, DEPT PHYS, ANN ARBOR, MI 48109 USA. NR 12 TC 6 Z9 6 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 70 EP 73 DI 10.1016/0921-4526(93)90497-T PG 4 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400016 ER PT J AU SMITH, JL FOWLER, CM FREEMAN, BL HULTS, WL KING, JC MUELLER, FM RICKEL, DG BROOKS, JS GOETTEE, JD MANKIEWICH, PM DEOBALDIA, EI SKOCPOL, WJ OMALLEY, ML AF SMITH, JL FOWLER, CM FREEMAN, BL HULTS, WL KING, JC MUELLER, FM RICKEL, DG BROOKS, JS GOETTEE, JD MANKIEWICH, PM DEOBALDIA, EI SKOCPOL, WJ OMALLEY, ML TI FERMI-SURFACE AND CRITICAL-FIELD OF YBCO SO PHYSICA B-CONDENSED MATTER LA English DT Article ID SINGLE-CRYSTAL YBA2CU3OX AB We have measured extremal areas of the Fermi surface of YBa2Cu3O6.97 by the de Haas-van Alphen effect and the superconducting critical field H(c2)(T) by resistance measurements on epitaxial thin films of YBa2Cu3O7 (both called YBCO). Magnetic fields up to 140 T were used in flux compression experiments. We have tentatively identified another piece of the Fermi surface with an area of 22 kT, which is larger than expected. By both the de Haas-van Alphen effect and the resistance measurements, H(c2) with the applied magnetic field H parallel to the c axis of the YBCO is near 130 T. For H perpendicular to the c axis H(c2) is of the order of 900 T. C1 BOSTON UNIV, DEPT PHYS, BOSTON, MA 02215 USA. AT&T BELL LABS, HOLMDEL, NJ 07733 USA. RP SMITH, JL (reprint author), LOS ALAMOS NATL LAB, MAIL STOP K763, LOS ALAMOS, NM 87545 USA. RI Goettee, Jeffrey/L-4926-2015 NR 18 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 104 EP 106 DI 10.1016/0921-4526(93)90506-2 PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400025 ER PT J AU BULLOCK, GL SHIVARAM, BS HINKS, DG AF BULLOCK, GL SHIVARAM, BS HINKS, DG TI THERMODYNAMIC CONSTRAINTS FROM ULTRASOUND MEASUREMENTS IN UPT3 SO PHYSICA B-CONDENSED MATTER LA English DT Article ID PHASE-DIAGRAM; SUPERCONDUCTING PHASES; DOUBLE TRANSITION AB We show that using measurements of the longitudinal sound velocities in UPt3 in conjunction with the results of a model for the double superconducting transition in an unconventional superconductor it is possible to derive a number of thermodynamic parameters. The values derived for these parameters differ considerably from those obtained from direct measurements. This suggests that there are possibly other factors not considered in present theory which influence the ultrasound velocity in UPt3. C1 UNIV VIRGINIA, JESSE BEAMS PHYS LAB, CHARLOTTESVILLE, VA 22901 USA. ARGONNE NATL LAB, DIV MAT SCI & TECHNOL, ARGONNE, IL 60439 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 245 EP 247 DI 10.1016/0921-4526(93)90542-E PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400061 ER PT J AU KNETSCH, EA NIEUWENHUYS, GJ MYDOSH, JA HEFFNER, RH SMITH, JL AF KNETSCH, EA NIEUWENHUYS, GJ MYDOSH, JA HEFFNER, RH SMITH, JL TI NORMAL-STATE RESISTIVITY AND SPECIFIC-HEAT OF U1-XTHXBE13 SO PHYSICA B-CONDENSED MATTER LA English DT Article ID FERMION COMPOUND UBE13; (U,TH)BE13; FIELD AB Resistivity (0.4-300 K and 0-7 T) and specific heat (1.7-10 K) for U1-xThxBe13 with 0.00 less-than-or-equal-to x less-than-or-equal-to 0.06 were analysed using a sample with x = 0.06 as a reference compound. The low- T maxima in rho and C(p) both shift below the superconducting T(c) at the kink in the T(c)-x phase diagram and are not observed for higher thorium concentrations. These observations shed new light on the nonmonotonic dependence of T(c) on thorium concentration and the occurrence of a second superconducting transition. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87544 USA. RP KNETSCH, EA (reprint author), LEIDEN UNIV, KAMERLINGH ONNES LAB, 2300 RA LEIDEN, NETHERLANDS. NR 20 TC 11 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 251 EP 253 DI 10.1016/0921-4526(93)90544-G PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400063 ER PT J AU MOOK, HA SEAMAN, CL MAPLE, MB DELATORRE, MAL COX, DL MAKIVIC, M AF MOOK, HA SEAMAN, CL MAPLE, MB DELATORRE, MAL COX, DL MAKIVIC, M TI NEUTRON-SCATTERING STUDY OF THE QUADRUPOLAR KONDO ALLOY Y0.8U0.2PD3 SO PHYSICA B-CONDENSED MATTER LA English DT Article ID FERMI-LIQUID BEHAVIOR AB Inelastic neutron scattering measurements have been performed on a polycrystalline specimen of Y0.8U0.2Pd3 and on the nonmagnetic analog compound Y0.8Th0.2Pd3 using unpolarized neutrons. The magnetic contribution to the inelastic spectrum at T = 10 K exhibits two distinct peaks centered at energies E almost-equal-to 5 meV and 16 meV, attributed to broadened crystalline electric field (CEF) levels, with half widths at half maximum of approximately 3 meV and approximately 8 meV, respectively. The integrated intensities are consistent with GAMMA5 and GAMMA4 first and second excited state triplets lying above a GAMMA3 doublet ground state for tetravalent U ions in a cubic CEF. The absence of a pronounced low-energy (less-than-or-equal-to 4 meV almost-equal-to k(B)T(K)) quasielastic response provides further evidence that the nonmagnetic GAMMA3 doublet lies lowest in energy. These observations support the interpretation of the thermal, magnetic and transport properties in terms of the two-channel quadrupolar Kondo effect. C1 UNIV CALIF SAN DIEGO, DEPT PHYS, LA JOLLA, CA 92093 USA. UNIV CALIF SAN DIEGO, INST PURE & APPL PHYS SCI, LA JOLLA, CA 92093 USA. OHIO STATE UNIV, DEPT PHYS, COLUMBUS, OH 43210 USA. RP MOOK, HA (reprint author), OAK RIDGE NATL LAB, DIV SOLID STATE PHYS, OAK RIDGE, TN 37831 USA. RI Lopez de la Torre, Marco /K-6394-2014 OI Lopez de la Torre, Marco /0000-0002-9455-6733 NR 9 TC 26 Z9 26 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 341 EP 343 DI 10.1016/0921-4526(93)90569-R PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400088 ER PT J AU THOMPSON, JD CANFIELD, PC LACERDA, A HUNDLEY, MF FISK, Z OTT, HR FELDER, E CHERNIKOV, M MAPLE, MB VISANI, P SEAMAN, CL DELATORRE, MAL AEPPLI, G AF THOMPSON, JD CANFIELD, PC LACERDA, A HUNDLEY, MF FISK, Z OTT, HR FELDER, E CHERNIKOV, M MAPLE, MB VISANI, P SEAMAN, CL DELATORRE, MAL AEPPLI, G TI PHYSICS OF YBBIPT SO PHYSICA B-CONDENSED MATTER LA English DT Article AB YbBiPt has a low temperature linear specific heat coefficient of 8J/mol Yb K2 and a small specific heat anomaly at 0.4 K. We discuss new experiments on the specific heat of diluted YbBiPt, magnetic field dependent effects and electrical resistivity in pure YbBiPt. We argue that in this material the Kondo and crystal field energy scales are small and of comparable magnitude, placing YbBiPt in the same class as many uranium heavy electron compounds. C1 EIDGENOSSICHE TH ZURICH, ZURICH, SWITZERLAND. AT&T BELL LABS, MURRAY HILL, NJ 07920 USA. UNIV CALIF SAN DIEGO, LA JOLLA, CA 92093 USA. RP THOMPSON, JD (reprint author), LOS ALAMOS NATL LAB, MS K764, LOS ALAMOS, NM 87545 USA. RI Canfield, Paul/H-2698-2014; Lopez de la Torre, Marco /K-6394-2014 OI Lopez de la Torre, Marco /0000-0002-9455-6733 NR 8 TC 11 Z9 11 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 355 EP 357 DI 10.1016/0921-4526(93)90572-N PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400091 ER PT J AU HUNDLEY, MF LACERDA, A CANFIELD, PC THOMPSON, JD FISK, Z AF HUNDLEY, MF LACERDA, A CANFIELD, PC THOMPSON, JD FISK, Z TI MAGNETORESISTANCE OF THE KONDO INSULATOR CE3BI4PT3 SO PHYSICA B-CONDENSED MATTER LA English DT Article ID GAP AB The magnetoresistance (MR) of the narrow-gap Kondo insulator Ce3Bi4Pt3 and its non-magnetic analog La3Bi4Pt3 have been measured in magnetic fields to 10T and in the temperature range 2-300 K. Ce3Bi4Pt3 exhibits a large negative MR component below 7 K. At higher temperatures this negative component progressively decreases and a positive contribution becomes evident. Above 75 K the MR is positive at all fields and saturates to a value of a few percent. The non-magnetic analog La3Bi4Pt3 exhibits the same positive magnetoresistance present in Ce3Bi4Pt3 as well as a conventional positive H-2 term at low temperatures. We discuss potential mechanisms for both the common positive effect and the large negative MR present in Ce3Bi4Pt3. RP HUNDLEY, MF (reprint author), LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. RI Canfield, Paul/H-2698-2014 NR 12 TC 17 Z9 17 U1 3 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 425 EP 427 DI 10.1016/0921-4526(93)90593-U PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400112 ER PT J AU DHAR, SK GSCHNEIDNER, KA VIJAYARAGHAVAN, R AF DHAR, SK GSCHNEIDNER, KA VIJAYARAGHAVAN, R TI YBNISB - A POSSIBLE HEAVY-FERMION COMPOUND SO PHYSICA B-CONDENSED MATTER LA English DT Article ID SYSTEMS AB YbNiSb has a cubic MgAgAs-type structure and the Yb ions are trivalent. The heat capacity, C, measured in the range 2-20 K is temperature-independent between 2 and 8 K (1.9 J/mol K2) at zero field and shows magnetic field dependence. The value of C/T extrapolated to 0 K is 150 mJ/mol K2. The resistivity (3.6 mOMEGA cm at 300 K) decreases with temperature. These data indicate that YbNiSb is a possible low-carrier heavy-fermion compound. C1 IOWA STATE UNIV SCI & TECHNOL, AMES LAB, AMES, IA 50010 USA. RP DHAR, SK (reprint author), TATA INST FUNDAMENTAL RES, SOLID STATE PHYS GRP, HOMI BHABHA RD, BOMBAY 400005, INDIA. NR 12 TC 6 Z9 6 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 463 EP 465 DI 10.1016/0921-4526(93)90604-5 PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400123 ER PT J AU HOLTMEIER, S HAEN, P DEVISSER, A LACERDA, A LEJAY, P FLOUQUET, J AF HOLTMEIER, S HAEN, P DEVISSER, A LACERDA, A LEJAY, P FLOUQUET, J TI MAGNETOVOLUME EFFECTS IN CE0.985Y0.015RU2SI2 SO PHYSICA B-CONDENSED MATTER LA English DT Article ID METAMAGNETIC TRANSITION; CERU2SI2 AB We report on the thermal expansion alpha(T) and magnetostriction lambda(B) of monocrystalline Ce0.985Y0.015Ru2Si2 for 0.1 K < T < 1 K and B < 11 T. The one parameter scaling law previously observed for CeRu2Si2 and Ce0.95La0.05Ru2Si2 is also valid for the present alloy. The variation of gamma versus B is determined from alpha(T) in the field. The width of the pseudometamagnetic transition is discussed. C1 UNIV AMSTERDAM, VAN DER WAALS ZEEMAN LAB, AMSTERDAM, NETHERLANDS. LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. CENG, MC, DRF, F-38041 GRENOBLE, FRANCE. UNIV JOSEPH FOURIER, CRTBT LAB, CNRS, F-38042 GRENOBLE, FRANCE. RP HOLTMEIER, S (reprint author), CRTBT LAB, CNRS, F-38042 GRENOBLE 09, FRANCE. NR 9 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 521 EP 524 DI 10.1016/0921-4526(93)90622-D PG 4 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400141 ER PT J AU ROBINSON, RA KOHGI, M OSAKABE, T CANFIELD, PC KAMIYAMA, T NAKANE, T FISK, Z THOMPSON, JD AF ROBINSON, RA KOHGI, M OSAKABE, T CANFIELD, PC KAMIYAMA, T NAKANE, T FISK, Z THOMPSON, JD TI CRYSTAL-FIELD LEVELS IN YBBIPT SO PHYSICA B-CONDENSED MATTER LA English DT Article ID NEUTRON AB The new massive-electron system YbBiPt has been studied by means of neutron inelastic scattering at temperatures between 3.3 and 77 K, using the crystal-analyser spectrometer LAM-40. Crystal field excitations have been observed at approximately 6meV and at very low energy. There is also significant quasielastic scattering and the higher-energy level softens slightly with increasing temperature. Although these observations are in qualitative agreement with the bulk susceptibility measurements, our data suggest that the first excited crystal-field level is much lower in energy than had been deduced from bulk measurements. C1 NATL LAB HIGH ENERGY PHYS, TSUKUBA 305, JAPAN. TOHOKU UNIV, DEPT PHYS, SENDAI, MIYAGI 980, JAPAN. TOHOKU UNIV, INST MAT SCI, SENDAI, MIYAGI 980, JAPAN. HOKKAIDO UNIV, DEPT CHEM, SAPPORO, HOKKAIDO 060, JAPAN. UNIV CALIF SAN DIEGO, DEPT PHYS, LA JOLLA, CA 92093 USA. RP ROBINSON, RA (reprint author), LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. RI Canfield, Paul/H-2698-2014 NR 9 TC 12 Z9 12 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 550 EP 552 DI 10.1016/0921-4526(93)90631-F PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400150 ER PT J AU UWATOKO, Y OOMI, G THOMPSON, JD CANFIELD, PC FISK, Z AF UWATOKO, Y OOMI, G THOMPSON, JD CANFIELD, PC FISK, Z TI ELECTRICAL-RESISTIVITY AND EFFECT OF PRESSURE ON THE THERMAL-EXPANSION OF A SINGLE-CRYSTAL OF YBCU2SI2 SO PHYSICA B-CONDENSED MATTER LA English DT Article AB Electrical resistivity rho(T) and thermal expansion DELTAl/l were measured for the intermediate valence compound (IVC) YbCu2Si2 and its counterpart LuCu2Si2 between 4.2 K and 300 K. It was found that the thermal expansion coefficient alpha(T) has a negative minimum around 31 K (= T(min)) at atmospheric pressure and T(min) decreases with increasing pressure at the rate partial derivative T(min)/partial derivative T = -0.45 K/kbar. C1 LOS ALAMOS NATL LAB, DIV PHYS, LOS ALAMOS, NM 87545 USA. RP UWATOKO, Y (reprint author), KUMAMOTO UNIV, FAC GEN EDUC, DEPT PHYS, KUMAMOTO 860, JAPAN. RI Canfield, Paul/H-2698-2014 NR 13 TC 9 Z9 9 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 593 EP 595 DI 10.1016/0921-4526(93)90645-M PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400164 ER PT J AU AMATO, A CANFIELD, PC FEYERHERM, R FISK, Z GYGAX, FN HEFFNER, RH KNETSCH, EA MACLAUGHLIN, DE OTT, HR SCHENCK, A THOMPSON, JD ZIMMERMANN, U AF AMATO, A CANFIELD, PC FEYERHERM, R FISK, Z GYGAX, FN HEFFNER, RH KNETSCH, EA MACLAUGHLIN, DE OTT, HR SCHENCK, A THOMPSON, JD ZIMMERMANN, U TI ZERO-FIELD MUON SPIN RELAXATION STUDIES OF LOW-TEMPERATURE MAGNETISM IN YBXY1-XBIPT (X = 1.0 AND 0.5) SO PHYSICA B-CONDENSED MATTER LA English DT Article AB Zero-field muon spin relaxation studies are reported for crystalline YbxY1-xBiPt for x = 1.0 and 0.5. YbBiPt exhibits an extremely large C(p)/T ratio gamma congruent-to 8J/(K2 mol Yb) below T congruent-to 0.2K and shows evidence for some type of magnetic order below 0.4 K from chi(AC). The muSR data are consistent with a highly frustrated spin system segmented into two types of magnetic domains, one of which freezes into a disordered state below T(f) congruent-to 0.4-0.5 K at a temperature relatively independent of the Yb concentration. The frozen spin moment of approximately 0.1mu(B) is highly reduced from the high temperature free-ion value, and is independent of the Yb concentration. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. LEIDEN UNIV, KAMERLINGH ONNES LAB, 2300 RA LEIDEN, NETHERLANDS. UNIV CALIF RIVERSIDE, RIVERSIDE, CA 92521 USA. SWISS FED INST TECHNOL, FESTKORPERPHYS LAB, CH-8093 ZURICH, SWITZERLAND. RP AMATO, A (reprint author), ETH ZURICH, INST MITTELENERGIEPHYS, CH-5232 VILLIGEN, SWITZERLAND. RI Feyerherm, Ralf/F-5487-2013; Canfield, Paul/H-2698-2014; Amato, Alex/H-7674-2013 OI Feyerherm, Ralf/0000-0003-3034-4210; Amato, Alex/0000-0001-9963-7498 NR 4 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 615 EP 617 DI 10.1016/0921-4526(93)90652-M PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400171 ER PT J AU ARONSON, MC CLARKE, R DEMCZYK, BG COLES, BR SMITH, JL DEVISSER, A VORENKAMP, T FRANSE, JJM AF ARONSON, MC CLARKE, R DEMCZYK, BG COLES, BR SMITH, JL DEVISSER, A VORENKAMP, T FRANSE, JJM TI STACKING-FAULTS IN UPT3 SO PHYSICA B-CONDENSED MATTER LA English DT Article ID SUPERCONDUCTING PHASES; DEPENDENCE; PRESSURE AB Atomic resolution transmission electron microscopy and X-ray diffraction measurements have been combined to investigate the microstructure of superconducting UPt3. Regions of a second double hexagonal phase with a typical dimension of 25-30 angstrom are found to occupy approximately 3% of the total sample volume. C1 UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED, LONDON SW7 2AZ, ENGLAND. LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. UNIV AMSTERDAM, 1018 XE AMSTERDAM, NETHERLANDS. RP ARONSON, MC (reprint author), UNIV MICHIGAN, ANN ARBOR, MI 48109 USA. NR 15 TC 15 Z9 15 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 788 EP 791 DI 10.1016/0921-4526(93)90705-B PG 4 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400224 ER PT J AU LACERDA, A ZHANG, H CANFIELD, PC HUNDLEY, MF FISK, Z THOMPSON, JD SEAMAN, CL MAPLE, MB AEPPLI, G AF LACERDA, A ZHANG, H CANFIELD, PC HUNDLEY, MF FISK, Z THOMPSON, JD SEAMAN, CL MAPLE, MB AEPPLI, G TI NARROW-GAP SIGNATURE OF FEXCO1-XSI SINGLE-CRYSTALS SO PHYSICA B-CONDENSED MATTER LA English DT Article AB Heat capacity, resistance, and magnetic susceptibility have been measured on FeSi, Fe0.90Co0.10Si, Fe0.10Co0.90Si, and CoSi single crystals. From resistance experiments, the activation energy (DELTA) shows a small variation from DELTA almost-equal-to 310 K in FeSi to DELTA almost-equal-to 325 K for the Fe0.90Co0.10Si compound. For the 90% Co compound the gap signature disappears completely. Heat capacity experiments performed in the temperature range 1.5 K < T < 20 K reveal an increasing Sommerfeld coefficient (gamma) with increasing Co content. A comparison is made with the hybridization gapped material Ce3Bi4Pt3. C1 UNIV CALIF SAN DIEGO, DEPT PHYS, LA JOLLA, CA 92093 USA. AT&T BELL LABS, MURRAY HILL, NJ 07974 USA. RP LACERDA, A (reprint author), LOS ALAMOS NATL LAB, PULSED FIELD FACIL, NATL HIGH MAGNET FIELD LAB, MSE536, LOS ALAMOS, NM 87545 USA. RI Canfield, Paul/H-2698-2014 NR 11 TC 15 Z9 15 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 1043 EP 1045 DI 10.1016/0921-4526(93)90780-A PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400299 ER PT J AU WELP, U FLESHLER, S KWOK, WK CRABTREE, GW CARLSON, KD WANG, HH GEISER, U WILLIAMS, JM HITSMAN, VM AF WELP, U FLESHLER, S KWOK, WK CRABTREE, GW CARLSON, KD WANG, HH GEISER, U WILLIAMS, JM HITSMAN, VM TI WEAK FERROMAGNETISM IN KAPPA-(ET)2CU[N(CN)2]CL SO PHYSICA B-CONDENSED MATTER LA English DT Article AB We present magnetization measurements at ambient pressure on kappa-(ET)2Cu[N(CN)2]Cl, an organic salt that is superconducting under pressure (T(c) = 12.8 K at 0.3 kbar). An antiferromagnetic transition near 45 K and, for the first time in this class of materials, a transition near 22K to a state displaying weak ferromagnetic hysteresis with a saturation moment of 8 x 10(-4) mu(B)/formula are observed. This low-temperature state is characterized by a sequence of first-order magnetization jumps. C1 ARGONNE NATL LAB, DIV CHEM, ARGONNE, IL 60439 USA. PURDUE UNIV, W LAFAYETTE, IN 47907 USA. ALMA COLL, DEPT CHEM, ALMA, MI 48801 USA. RP WELP, U (reprint author), ARGONNE NATL LAB, DIV MAT SCI, ARGONNE, IL 60439 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 1993 VL 186-88 BP 1065 EP 1067 DI 10.1016/0921-4526(93)90787-7 PG 3 WC Physics, Condensed Matter SC Physics GA LK394 UT WOS:A1993LK39400306 ER PT J AU MCKERNAN, S ZETTL, A AF MCKERNAN, S ZETTL, A TI HIGH-TEMPERATURE RESISTIVITY AND OXYGEN DIFFUSION IN BI2SR2CACU2OX SO PHYSICA C LA English DT Article ID SUPERCONDUCTING PROPERTIES; SINGLE-CRYSTALS; OXIDE; STATE AB We have investigated high temperature electrical resistivity and oxygen diffusion in single crystal Bi2Sr2CaCu2Ox. Above approximately 400-degrees-C, oxygen is readily exchanged with the sample environment which strongly influences the functional form of the resistivity. By changing the partial pressure of oxygen in the sample environment and by continuously monitoring the sample resistance at fixed temperature, we determine oxygen diffusion constants at selected temperatures. In-diffusion is found to be significantly faster than out-diffusion. The in-diffusion data suggest an activated form with a diffusion constant given by D=D0 exp(-E/k(B)T) with D0=11.7 cm2/s and E=1.16 eV. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP MCKERNAN, S (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Zettl, Alex/O-4925-2016 OI Zettl, Alex/0000-0001-6330-136X NR 11 TC 14 Z9 14 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 1993 VL 209 IS 4 BP 585 EP 590 DI 10.1016/0921-4534(93)90579-F PG 6 WC Physics, Applied SC Physics GA LA814 UT WOS:A1993LA81400035 ER PT J AU EMERY, VJ KIVELSON, SA AF EMERY, VJ KIVELSON, SA TI FRUSTRATED ELECTRONIC PHASE-SEPARATION AND HIGH-TEMPERATURE SUPERCONDUCTORS SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article ID HIGH-TC SUPERCONDUCTIVITY; PHOTOINDUCED-ABSORPTION SPECTROSCOPY; 2-DIMENSIONAL HUBBARD-MODEL; ONE-DIMENSIONAL CONDUCTORS; MUON-SPIN-RELAXATION; SINGLE-CRYSTAL; DOPED ANTIFERROMAGNET; INFRARED-ABSORPTION; NEUTRON-SCATTERING; CHARGE-CARRIERS AB There is a strong tendency for dilute holes in an antiferromagnet to phase separate. (This is a generic feature of doping into a commensurate correlated insulating state.) We review the general and model-specific theoretical arguments that support this conclusion for neutral holes. In the presence of long-range Coulomb interactions, there is frustated phase separation leading to large-amplitude, low-energy fluctuations in the hole density at intermediate length scales, provided the dielectric constant is sufficiently large. We describe extensive experimental evidence showing that such ''clumping'' of the holes is an important feature of the cuprate superconductors. We also summarize theoretical results which suggest that frustrated phase separation may account for the anomalous properties of the normal state and give rise to high-temperature superconductivity. C1 UNIV CALIF LOS ANGELES, DEPT PHYS, LOS ANGELES, CA 90024 USA. RP EMERY, VJ (reprint author), BROOKHAVEN NATL LAB, DEPT PHYS, UPTON, NY 11973 USA. NR 124 TC 612 Z9 612 U1 3 U2 27 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 1993 VL 209 IS 4 BP 597 EP 621 DI 10.1016/0921-4534(93)90581-A PG 25 WC Physics, Applied SC Physics GA LA814 UT WOS:A1993LA81400037 ER PT J AU WEIGERT, S LITTLEJOHN, RG AF WEIGERT, S LITTLEJOHN, RG TI DIAGONALIZATION OF MULTICOMPONENT WAVE-EQUATIONS WITH A BORN-OPPENHEIMER EXAMPLE SO PHYSICAL REVIEW A LA English DT Article ID GEOMETRIC PHASES AB A general method to decouple multicomponent linear wave equations is presented. First, the Weyl calculus is used to transform operator relations into relations between c-number valued matrices. Then it is shown that the symbol representing the wave operator can be diagonalized systematically up to arbitrary order in an appropriate expansion parameter. After transforming the symbols back to operators, the original problem is reduced to solving a set of linear uncoupled scalar wave equations. The procedure is exemplified for a particle with a Born-Oppenheimer-type Hamiltonian valid through second order in HBAR. The resulting effective scalar Hamiltonians are seen to contain an additional velocity-dependent potential. This contribution has not been reported in recent studies investigating the adiabatic motion of a neutral particle moving in an inhomogeneous magnetic field. Finally, the relation of the general method to standard quantum-mechanical perturbation theory is discussed. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP WEIGERT, S (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Weigert, Stefan/B-9499-2008 OI Weigert, Stefan/0000-0002-6647-3252 NR 21 TC 17 Z9 17 U1 2 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3506 EP 3512 DI 10.1103/PhysRevA.47.3506 PN A PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500012 ER PT J AU WANG, SJ CHU, SY AF WANG, SJ CHU, SY TI LEVEL DYNAMICS - AN APPROACH TO THE STUDY OF AVOIDED LEVEL-CROSSINGS AND TRANSITION TO CHAOS SO PHYSICAL REVIEW A LA English DT Article ID SPECTRUM AB The Dyson-Pechukas level dynamics has been reformulated and made suitable for studying avoided level crossings and transition to chaos. The N-level dynamics is converted into a many-body problem of one-dimensional Coulomb gas with N-constituent particles having intrinsic excitations. It is shown that local fluctuation of the level distribution is generated by a large number of avoided level crossings. The role played by avoided level crossings in generating chaoticity in level dynamics is similar to the role played by short-range collisions in causing thermalization in many-body dynamics. Furthermore, the effect of level changing rates in producing avoided level crossings is the same as particle velocities in causing particle-particle collisions. A one-dimensional su(2) Hamiltonian has been constructed as an illustration of the level dynamics, showing how the avoided level crossings cause the transition from a regular distribution to the chaotic Gaussian orthogonal ensemble (GOE) distribution of the levels. The existence of the one-dimensional su(2) Hamiltonian which can show both GOE and Poisson level statistics is remarkable and deserves further investigation. C1 LANZHOU UNIV,DEPT MODERN PHYS,LANZHOU 730000,PEOPLES R CHINA. CHINESE CTR ADV SCI & TECHNOL WORLD LAB,CTR THEORET PHYS,BEIJING,PEOPLES R CHINA. RP WANG, SJ (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 17 TC 10 Z9 12 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3546 EP 3553 DI 10.1103/PhysRevA.47.3546 PN A PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500018 ER PT J AU YEH, LW AF YEH, LW TI ERMAKOV-LEWIS INVARIANT FROM THE WIGNER FUNCTION OF A SQUEEZED COHERENT STATE SO PHYSICAL REVIEW A LA English DT Article ID TIME-DEPENDENT INVARIANTS; QUANTUM-MECHANICS; OSCILLATOR; PHYSICS AB Using the phase-space picture (Weyl-Wigner-Moyal formalism) of quantum mechanics for time-dependent Hamiltonians, we show that the Ermakov-Lewis invariant of a generalized harmonic oscillator can be derived from the Wigner function of a squeezed coherent state. The geometric meaning of this invariant is clarified and realized via the Wigner ellipse in phase space. C1 LAWRENCE BERKELEY LAB, DIV PHYS, BERKELEY, CA 94720 USA. RP YEH, LW (reprint author), UNIV CALIF BERKELEY, DEPT PHYS, BERKELEY, CA 94720 USA. NR 22 TC 5 Z9 6 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 EI 1094-1622 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3587 EP 3592 DI 10.1103/PhysRevA.47.3587 PN A PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500021 ER PT J AU PHILLIPS, WR COPNELL, J BANES, DW REHM, KE AHMAD, I GLAGOLA, BG HENNING, W KUTSCHERA, W SCHIFFER, JP AF PHILLIPS, WR COPNELL, J BANES, DW REHM, KE AHMAD, I GLAGOLA, BG HENNING, W KUTSCHERA, W SCHIFFER, JP TI ELECTRON-NUCLEUS INTERACTIONS IN FEW-ELECTRON FE IONS SO PHYSICAL REVIEW A LA English DT Article ID FLUORESCENCE YIELD; HELIUMLIKE; STATE; HYDROGENLIKE; DEPENDENCE; LIFETIMES AB Measurements have been made of the total decay rates of the 14.4-keV level in the Fe-57 nucleus in highly charged Fe ions having one to six electrons outside the nucleus. Results are 10.0(9), 7.06(18), 7.36(14), 7.16(11), 7.10(23), 7.28(25), and 6.92(46), in units of 10(6) s-1, for ions of charge states q from 25 to 19, respectively. For the q = 25 single-electron ion the result quoted is for the ion in which the spin of the 1s1/2 electron and the excited nuclear state are coupled to give quantum number F = 1. Measurements have also been made of the K-shell fluorescent yields for ions in charge states q (before K-vacancy production) from 22 to 19. Results are 0.62(1), 0.50(1), 0.48(2), and 0.50(6), respectively. These data are discussed and compared with theoretical predictions. C1 ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. RP PHILLIPS, WR (reprint author), UNIV MANCHESTER,MANCHESTER M13 9PL,LANCS,ENGLAND. NR 34 TC 22 Z9 22 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3682 EP 3691 DI 10.1103/PhysRevA.47.3682 PN A PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500029 ER PT J AU CHEN, MH CHENG, KT JOHNSON, WR AF CHEN, MH CHENG, KT JOHNSON, WR TI RELATIVISTIC CONFIGURATION-INTERACTION CALCULATIONS OF N=2 TRIPLET-STATES OF HELIUM-LIKE IONS SO PHYSICAL REVIEW A LA English DT Article ID MANY-ELECTRON ATOMS; ISOELECTRONIC SEQUENCE; 2-ELECTRON IONS; TRANSITION ENERGIES; 2S-2P TRANSITIONS; BREIT INTERACTION; HEAVY ATOMS; DIRAC-FOCK; LAMB SHIFT; NICKEL AB Eigenfunctions and eigenvalues of the relativistic no-pair Hamiltonian are determined for n = 2 triplet states of heliumlike ions with charges in the range Z = 5-100. The eigenfunctions are expanded in a basis of two-electron wave functions constructed from Dirac-Coulomb orbitals restricted to a finite cavity. The Hamiltonian matrix is evaluated and Davidson's method is then used to determine the lowest few eigenfunctions and eigenvalues. These calculations, which include the Coulomb interaction and the retarded Breit interaction, are corrected for QED and mass-polarization effects using values from Drake's unified method and are compared with other calculations and with experiment. For low-Z ions, the present calculations agree well with many-body perturbation theory and with the unified method, but disagree substantially with multiconfiguration Dirac-Fock (MCDF) calculations corrected for correlations. At Z = 36, our term energies axe lower than the unified method by lambdaalpha4Z4 a.u., where lambda = 0.033, 0.51, 0.16, and 0.003 for the 2 3S1, 2 3P0, 2 3P1, and 2 3P2 states, respectively. For Z = 47 and 64, the present values of the 2 3P0-2 3P1 fine structure agree better with MCDF predictions than with the unified method. The energy intervals 2 3P0-2 3S1, 2 3p1-2 3S1, 2 3P2-2 3S1, and 2 3P0-2 3P1 are consistent with experiment throughout the entire range of Z. C1 UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556. RP CHEN, MH (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,LIVERMORE,CA 94550, USA. NR 45 TC 147 Z9 148 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3692 EP 3703 DI 10.1103/PhysRevA.47.3692 PN A PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500030 ER PT J AU CHEN, MH AF CHEN, MH TI RELATIVISTIC-INTERMEDIATE-COUPLING CALCULATIONS OF ANGULAR-DISTRIBUTIONS IN RESONANT AUGER DECAY SO PHYSICAL REVIEW A LA English DT Article ID SYNCHROTRON RADIATION; SELECTIVE EXCITATION; SHAKE-OFF; X-RAYS; ELECTRONS; KR; AR; AUTOIONIZATION; POLARIZATION; ANISOTROPY AB The angular-distribution parameters of the resonant Auger transitions induced by photoexcitation have been calculated for the L23-M23M23, M45-N23N23 and N45-O23O23 transitions in Ar, Kr, and Xe, respectively. The calculations are carried out using the multiconfiguration Dirac-Fock method in intermediate coupling with configuration interaction. A two-step model is employed to describe the resonant Auger process. As in the case of normal Auger decay, inclusion of the effect of intermediate coupling removes the major discrepancy between theory based on the spectator model and experiment. RP CHEN, MH (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV HIGH TEMP PHYS,LIVERMORE,CA 94550, USA. NR 23 TC 41 Z9 41 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3733 EP 3738 DI 10.1103/PhysRevA.47.3733 PN A PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500034 ER PT J AU TRABERT, E SULEIMAN, J CHENG, S BERRY, HG DUNFORD, RW KANTER, EP KURTZ, C LIVINGSTON, AE KUKLA, KW SERPA, FG CURTIS, LJ AF TRABERT, E SULEIMAN, J CHENG, S BERRY, HG DUNFORD, RW KANTER, EP KURTZ, C LIVINGSTON, AE KUKLA, KW SERPA, FG CURTIS, LJ TI EXPERIMENTAL TRANSITION-PROBABILITIES OF INTERCOMBINATION TRANSITIONS IN MG-LIKE AND AL-LIKE IONS OF BROMINE SO PHYSICAL REVIEW A LA English DT Article ID I ISOELECTRONIC SEQUENCE; BEAM-FOIL LIFETIMES; ENERGY-LEVEL SCHEME; OSCILLATOR-STRENGTHS; RESONANCE TRANSITIONS; LINE STRENGTHS; HELIUM-LIKE; NA-LIKE; SPECTRA; CU AB Time-resolved extreme ultraviolet spectra of foil-excited 120-MeV Br ions have been recorded, using a spectrometer equipped with a position-sensitive detector. The spectra near lambda=20-30 nm were measured at times after excitation of up to 6 ns. Prominent in the delayed spectra were the long-lived decays of the intercombination transitions in the Mg-like Br23+ and Al-like Br22+ ions. The present paper reports on lifetime measurements for intercombination transitions in highly charged bromine ions using such a position-sensitive detector. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. UNIV NOTRE DAME,NOTRE DAME,IN 46556. UNIV TOLEDO,TOLEDO,OH 43606. RP TRABERT, E (reprint author), RUHR UNIV BOCHUM,W-4630 BOCHUM,GERMANY. RI Kurtz, Chalres/G-1037-2011 OI Kurtz, Chalres/0000-0003-2606-0864 NR 49 TC 27 Z9 27 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3805 EP 3809 DI 10.1103/PhysRevA.47.3805 PN A PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500043 ER PT J AU GAITHER, CC BREINIG, M BERRYMAN, JW HASSON, BF RICHARDS, JD PRICE, K AF GAITHER, CC BREINIG, M BERRYMAN, JW HASSON, BF RICHARDS, JD PRICE, K TI COINCIDENT DETECTION OF ELECTRONS EJECTED AT LARGE ANGLES AND TARGET RECOIL IONS PRODUCED IN MULTIPLY IONIZING COLLISIONS FOR THE 1-MEV/U O-Q++AR COLLISION SYSTEM SO PHYSICAL REVIEW A LA English DT Article ID HE COLLISIONS; BINARY PEAK; IONIZATION; EMISSION; DYNAMICS; NEON AB The angular distributions of energetic electrons ejected at angles between 45-degrees and 135-degrees with respect to the incident-beam direction have been measured in coincidence with the charge states of the target recoil ions produced in multiply ionizing collisions for the I-MeV/u O(q)+ (q=4,7)+Ar collision systems. These measurements have been made for approximately 179-, approximately 345-, and approximately 505-eV electrons. Additionally, the energy distributions of electrons ejected into specific angular regions have been measured. Ar LMM satellite Auger electrons appear as a peak in the energy spectrum of electrons ejected at all large angles. The center of this peak is found at an electron energy of approximately 179 eV. Electrons with approximately 179 eV energy, ejected at large angles, are preferentially produced in coincidence with recoil ions of charge state 4+. Electrons with approximately 345 eV energy and approximately 505 eV energy ejected at large angles are preferentially produced in coincidence with recoil ions of charge state 3+. The angular distributions for these electrons are strongly peaked in the forward direction; essentially no electrons are observed at angles larger than 90-degrees. These results are consistent with the dominant production mechanism for energetic electrons ejected at large angles being a binary-encounter process. Differential cross sections have been calculated from these angular distributions. They are on the order of 10(-21) cm2/(eV sr). C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP GAITHER, CC (reprint author), UNIV TENNESSEE,KNOXVILLE,TN 37996, USA. NR 21 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3878 EP 3887 DI 10.1103/PhysRevA.47.3878 PN A PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500050 ER PT J AU SHIMAKURA, N SUZUKI, S KIMURA, M AF SHIMAKURA, N SUZUKI, S KIMURA, M TI MOLECULAR TREATMENT OF ELECTRON-CAPTURE AT LOW TO INTERMEDIATE COLLISION ENERGIES - COLLISIONS OF B-4+ IONS WITH H-ATOMS SO PHYSICAL REVIEW A LA English DT Article ID TOTAL CROSS-SECTIONS; CHARGE-TRANSFER AB Partial and total cross sections for electron capture in collisions of B4+ ions with H atoms from 100 meV/amu to 10 keV/amu have been rigorously determined by using the molecular-orbital expansion method modified by the inclusion of electron translation factors. Quantum-mechanical (3 channels) and semiclassical (12 channels) methods have been employed at collision energies lower than 30 eV/amu and higher than 15 eV/amu, respectively. The agreement of the present results with measurements above 1 keV/amu is reasonable. In our cross sections for the singlet manifold, rather large oscillatory structures are found below 10 eV/amu that are attributable to Stueckelberg-type oscillation. At collision energies below a few eV/amu, the B3+(1s3d) and B3+ (1s3p) states are the dominant states for the triplet and singlet manifolds, respectively. However, the B3+(1s3p) state for the triplet and B3+(1s3d) state for the singlet take over above these energies. At energies above 1 keV/amu, three states, the B3+(1s3s), B3+(1s3p), and B3+(1s3d) states, contribute equally to the electron-capture process. A comparison of the present B4+ results with previous results for different projectiles with the same charge (i.e., Be4+, C4+, and N4+) reveals that although the cross sections of all these systems lie roughly within a certain range of magnitudes at intermediate collision energies (E = 0.5-10 keV/amu), differences begin to emerge in magnitude and energy dependence below this energy. We examined the scalability of the cross section; some remarks on the scaling are given. C1 NIIGATA UNIV,FAC SCI,DEPT CHEM,NIIGATA 95021,JAPAN. ARGONNE NATL LAB,ARGONNE,IL 60439. RICE UNIV,DEPT PHYS,HOUSTON,TX 77251. RP SHIMAKURA, N (reprint author), NIIGATA UNIV,DEPT GEN EDUC,NIIGATA 95021,JAPAN. NR 24 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3930 EP 3936 DI 10.1103/PhysRevA.47.3930 PN A PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500055 ER PT J AU SCHNEIDER, D SCHIWIETZ, G DEWITT, D AF SCHNEIDER, D SCHIWIETZ, G DEWITT, D TI DOUBLY DIFFERENTIAL SECONDARY-ELECTRON YIELDS FOLLOWING 8-MEV/U U-68+-ION AND 3.5-MEV/U U-38+-ION IMPACT ON A THIN CARBON-FOIL TARGET SO PHYSICAL REVIEW A LA English DT Article ID EMISSION; PROJECTILES; COLLISIONS; ATOMS AB Doubly differential secondary-electron yields following the impact of 8-MeV/u U68+ and 3.5-MeV/u U38+ ions on 44-mug/cm2 carbon-foil targets have been investigated experimentally. Electron emission yields were determined for ejection angles varied between 0-degrees and 157-degrees and electron energies ranging from 10 eV to 8 keV. The experimental data are compared to results from a theoretical model for production and transport of fast electrons in solids. C1 HAHN MEITNER INST BERLIN GMBH,DEPT P,W-1000 BERLIN 39,GERMANY. RP SCHNEIDER, D (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV HIGH TEMP PHYS,LIVERMORE,CA 94550, USA. RI Schiwietz, Gregor/L-9813-2016 OI Schiwietz, Gregor/0000-0002-0128-6384 NR 26 TC 38 Z9 38 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3945 EP 3950 DI 10.1103/PhysRevA.47.3945 PN A PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB805 UT WOS:A1993LB80500057 ER PT J AU CLARK, MW SCHNEIDER, D DEWITT, D MCDONALD, JW BRUCH, R SAFRONOVA, UI TOLSTIKHINA, IY SCHUCH, R AF CLARK, MW SCHNEIDER, D DEWITT, D MCDONALD, JW BRUCH, R SAFRONOVA, UI TOLSTIKHINA, IY SCHUCH, R TI XE-L AND M X-RAY-EMISSION FOLLOWING XE-44-48+ ION IMPACT ON CU SURFACES SO PHYSICAL REVIEW A LA English DT Article ID HIGHLY CHARGED IONS; NEUTRALIZATION; EXCITATION; ARGON; TRAP AB The x-ray emission following the impact of highly charged Xe(q+) (q = 44-48) ions of 7-keV/q energy on a Cu surface has been measured. Theoretically we have derived an analytic formula which allows us to calculate the 21 -nl', 31 -nl', and 41 -nl' (n less-than-or-equal-to 5), L, M, and N x-ray transition energies averaged over spin and angular-momentum quantum numbers (L and S) as a function of the electron occupation numbers (k(i)) for the states Q = 1s1k2s2k2p3k3s4k3p5k3d6k4s7k4p8k4d9k4f10k5s11k5p12k. In accordance with our theoretical predictions the observed L x-ray structures shift toward higher energies and increase in intensity relative to the M x rays with increasing charge state. We have also observed an increase in high-energy satellite-line intensities with the increasing number of 2p vacancies. In calculating the radiative-transition probabilities we have found that the dominating electric-dipole transitions for L and M x rays are of the kind 2p - 3d and 3d - 4f, respectively. A comparison between measured peak positions and calculated transition energies reveals that direct feeding by approximately 13 electrons can explain the main features of the observed x-ray emission spectra. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RUSSIAN ACAD SCI,INST SPECT,TROITSK 142092,RUSSIA. MANNE SIEGBAHN INST PHYS,S-10405 STOCKHOLM,SWEDEN. RP CLARK, MW (reprint author), UNIV NEVADA,RENO,NV 89557, USA. RI Tolstikhina, Inga/L-3576-2013 NR 34 TC 45 Z9 48 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3983 EP 3997 DI 10.1103/PhysRevA.47.3983 PN B PG 15 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB807 UT WOS:A1993LB80700001 ER PT J AU VANEMMICHOVEN, PAZ HAVENER, CC HUGHES, IG ZEHNER, DM MEYER, FW AF VANEMMICHOVEN, PAZ HAVENER, CC HUGHES, IG ZEHNER, DM MEYER, FW TI EMISSION OF LOW-ENERGY ELECTRONS FROM MULTICHARGED IONS INTERACTING WITH METAL-SURFACES SO PHYSICAL REVIEW A LA English DT Article ID HIGHLY CHARGED IONS; AR IONS; TUNGSTEN SURFACE; ABOVE-SURFACE; NEUTRALIZATION; COLLISIONS; ATOMS AB Low-energy electron spectra are reported for 60- and 100-keV multicharged ions interacting at an incident angle of 20-degrees with Au and Cu surfaces. Analysis of the spectra indicate that at least two features contribute. The first feature represents the major contribution to the total electron yield and consists of 5-10-eV electrons emitted over a wide range of angles. The angular distribution of this component is not symmetric with respect to the surface normal, but shows an increase in the forward direction of the incident ions. It will be shown that this component arises predominantly from below the surface. Possible potential-emission mechanisms which may contribute will be discussed. The second feature, which constitutes a minor part of the overall electron emission, occurs at higher electron energies (approximately 20 eV), and is peaked at the extreme forward angles. Binary encounters between incident ions and metal electrons at the surface-vacuum interface will be shown to describe the main features of this component. At even higher electron energies ( > 40 eV) the spectra show a tail whose slope does not depend on either the initial charge state or kinetic energy of the incident ions. The invariance with kinetic energy is in sharp contrast with the corresponding experimental results from ion-atom collisions. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. JOINT INST HEAVY ION RES,HOLIFIELD HEAVY ION RES FACIL,OAK RIDGE,TN 37831. NR 32 TC 14 Z9 14 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 3998 EP 4006 PN B PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB807 UT WOS:A1993LB80700002 ER PT J AU CHANG, B BOLTON, PR FITTINGHOFF, DN AF CHANG, B BOLTON, PR FITTINGHOFF, DN TI CLOSED-FORM SOLUTIONS FOR THE PRODUCTION OF IONS IN THE COLLISIONLESS IONIZATION OF GASES BY INTENSE LASERS SO PHYSICAL REVIEW A LA English DT Article ID TUNNELING IONIZATION; MULTIPLE IONIZATION; NOBLE-GASES; RARE-GASES; RADIATION; ATOMS AB We derive in closed form the solutions to the rate equations for sequential field ionization of gases by a focused laser beam. We obtain the low-intensity and the high-intensity limits of the ion yield for each charge state produced by the laser pulse. Furthermore we derive the scaling laws for the appearance intensity and the saturation intensity of the ion yield. We find that the appearance intensity depends not only on the binding energy of the ionized electron but also on the quantum numbers of the shell from which the electron ionizes. We interpret this dependence on the quantum number to be the species dependence in the appearance intensities discussed by Meyerhofer and co-workers [Phys. Rev. Lett. 63, 2212 (1989)]. Formulas for five ionization models are presented. RP CHANG, B (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,LIVERMORE,CA 94550, USA. NR 18 TC 48 Z9 50 U1 2 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 4193 EP 4203 DI 10.1103/PhysRevA.47.4193 PN B PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB807 UT WOS:A1993LB80700020 ER PT J AU AMENDT, P LONDON, RA STRAUSS, M AF AMENDT, P LONDON, RA STRAUSS, M TI OPTIMIZATION OF SINGLE-STAGE X-RAY LASER COHERENCE SO PHYSICAL REVIEW A LA English DT Article ID EXCESS SPONTANEOUS EMISSION; HERMITIAN OPTICAL-SYSTEMS; GAIN-GUIDED AMPLIFIERS; NOISE; BEAM AB The effect of smoothly varying transverse gain and refraction profiles on x-ray laser coherence is analyzed by modally expanding the laser electric field within the paraxial approximation. Comparison with a square transverse profile reveals that smoothly varying profiles generally lead to a greatly reduced number of guided modes and a consequent improvement in transverse coherence length. However, the refractive defocusing responsible for enhanced coherence can also significantly degrade the coherent power of plasma x-ray lasers based on amplified spontaneous emission. A critical value of the Fresnel number is indicated, below which the coherent power rapidly decreases as refractive defocusing is increased. A parameter study of transverse coherence for current or planned x-ray laser experiments is provided. Comparison with ray-optics scaling laws for transverse coherence length and coherent power is made. An optimal coherent energy output of nearly 0.5 mJ in 100 psec is determined in Ni-like Ta at a wavelength of 45 angstrom for a saturated single-stage x-ray laser. A favorable comparison with coherent energy requirements for holographic imaging of biological samples is indicated. C1 NUCL RES CTR NEGEV,DEPT PHYS,IL-84190 BEER SHEVA,ISRAEL. RP AMENDT, P (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,LIVERMORE,CA 94550, USA. NR 35 TC 12 Z9 12 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1993 VL 47 IS 5 BP 4348 EP 4363 DI 10.1103/PhysRevA.47.4348 PN B PG 16 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA LB807 UT WOS:A1993LB80700038 ER PT J AU STOKES, HT DECKER, DL NELSON, HM JORGENSEN, JD AF STOKES, HT DECKER, DL NELSON, HM JORGENSEN, JD TI STRUCTURE OF POTASSIUM CYANIDE AT LOW-TEMPERATURE AND HIGH-PRESSURE DETERMINED BY NEUTRON-DIFFRACTION SO PHYSICAL REVIEW B LA English DT Article ID POWDER DIFFRACTION; PHASE-TRANSITIONS; KCN AB Neutron time of-flight powder-diffraction spectra have been obtained in potassium cyanide (KCN) at temperatures between 25 and 200 K and at pressures between 35 and 366 MPa. These data sample five different phases of KCN. In phase C, which exists at 366 MPa and below 170 K, the structure is determined to be paraelectric with the monoclinic space-group symmetry C2/c. This is in disagreement with a previous study which determined the structure to be ferroelectric with space-group symmetry Cc. In phase D, which exists at 366 MPa and below 120 K, the structure is determined to be paraelectric with the monoclinic space-group symmetry C2/m. The cyanide ions lie in mirror planes. In both phases C and D, the cyanide ions are ordered with respect to the direction of their bonds but disordered with respect to interchange of C and N. Also in these phases, line broadening due to an inhomogeneous shear strain was observed. A mathematical treatment of this phenomenon is given. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP STOKES, HT (reprint author), BRIGHAM YOUNG UNIV,DEPT PHYS & ASTRON,PROVO,UT 84602, USA. NR 23 TC 7 Z9 7 U1 0 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 MAY 1 PY 1993 VL 47 IS 17 BP 11082 EP 11092 DI 10.1103/PhysRevB.47.11082 PG 11 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400012 ER PT J AU KROHA, J SOUKOULIS, CM WOLFLE, P AF KROHA, J SOUKOULIS, CM WOLFLE, P TI LOCALIZATION OF CLASSICAL WAVES IN A RANDOM MEDIUM - A SELF-CONSISTENT THEORY SO PHYSICAL REVIEW B LA English DT Article ID TIGHT-BINDING MODEL; ANDERSON LOCALIZATION AB We study localization of classical waves in a model of point scatterers, idealizing a random arrangement of dielectric spheres (epsilon = 1 + DELTAepsilon) of volume V(s) and mean spacing a in a matrix (epsilon = 1). At distances >>a energy transport is diffusive. A self-consistent equation for the frequency-dependent diffusion coefficient is obtained and evaluated in the approximation where noncritical quantities are calculated in the coherent potential approximation. The velocity of energy transport and the phase velocity are renormalized in a similar way, even for finite-size scatterers. We find localization for d = 3 dimensions in a frequency window centered at omega congruent-to 2pi/a, and for values of the average change in the dielectric constant DELTAepsilonBAR = (V(s)a-3)DELTAepsilon exceeding approximately 1.7. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. RP KROHA, J (reprint author), UNIV KARLSRUHE,INST THEORIE KONDENSIERTEN MATERIE,W-7500 KARLSRUHE 1,GERMANY. RI Woelfle, Peter/N-8046-2013; Soukoulis, Costas/A-5295-2008; Kroha, Johann/B-5129-2008 NR 23 TC 37 Z9 37 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11093 EP 11096 DI 10.1103/PhysRevB.47.11093 PG 4 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400013 ER PT J AU LOVE, SP HUCKETT, SC WORL, LA FRANKCOM, TM EKBERG, SA SWANSON, BI AF LOVE, SP HUCKETT, SC WORL, LA FRANKCOM, TM EKBERG, SA SWANSON, BI TI FAR-INFRARED SPECTROSCOPY OF HALOGEN-BRIDGED MIXED-VALENCE PLATINUM-CHAIN SOLIDS - ISOTOPE-SUBSTITUTION STUDIES SO PHYSICAL REVIEW B LA English DT Article ID PEIERLS-HUBBARD MODEL; N-ELECTRONS SYSTEM; RESONANCE RAMAN-SPECTRA; METAL-COMPLEXES; LATTICE-RELAXATION; CRYSTAL-STRUCTURE; PRESSURE; PHONONS; ABSORPTION; SOLITON AB Far-infrared transmittance measurements are performed on a series of isotopically labeled samples of the quasi-one-dimensional solids [Pt(en)2][Pt(en2X2][ClO4]4, (en) = ethylenediamine and X = Cl, Br, or 1. Pronounced shifts upon deuteration of the (en) ligands reveal that several absorption features previously attributed to localized vibrational modes of chain defects are in fact (en) ligand modes. Recognition of these ligand modes resolves the previous ambiguity over the assignment of the infrared-active chain phonons, permitting the unambiguous assignment of the 238.7-cm-1 feature in the bromide material to the asymmetric stretch (v2) chain phonon, and strongly suggesting the 184.2-cm-1 feature in the iodide is the V2 phonon of that material. A high-resolution examination of the chloride, prepared with both natural Cl isotopic abundance and with nearly pure Cl-35 , reveals a Cl isotopic fine structure that allows conclusive identification of the 359.1-cm-1 feature as the V2 chain phonon. Lattice-dynamics calculations using a harmonic-linear-chain model with randomly distributed Cl isotopes yield good agreement with experiment and reveal that isotopic disorder leads to pronounced vibrational localization in PtCl, with the observed fine structure arising from modes residing on a few distinct sequences of isotopes occurring with high probability. The radical difference between the infrared fine structure of PtCl and that previously reported for the Raman-active chain mode is found to result from differences in the dispersion curves for the two phonon branches, and allows indirect determination of these dispersion curves. RP LOVE, SP (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. OI Love, Steven/0000-0003-0588-9622 NR 48 TC 26 Z9 26 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11107 EP 11123 DI 10.1103/PhysRevB.47.11107 PG 17 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400015 ER PT J AU BARNES, T KOVARIK, MD AF BARNES, T KOVARIK, MD TI MONTE-CARLO STUDY OF ONE-HOLE BAND-STRUCTURE IN THE T-J MODEL SO PHYSICAL REVIEW B LA English DT Article ID ANTIFERROMAGNETIC HEISENBERG-MODEL; GUIDED RANDOM-WALKS; PHASE-SEPARATION; HUBBARD-MODEL; SQUARE LATTICE; GROUND-STATE; SYSTEMS AB We present Monte Carlo results for the band structure of the lowest-lying S(tot) = 1/2 one-hole band in the t-J model on 4 x 4 and 6 x 6 lattices. In this paper we report measurements for all k states in the small t/J regime 0 less-than-or-equal-to t/J less-than-or-equal-to 0.2, and extrapolate to 0 less-than-or-equal-to t/J less-than-or-equal-to 0.5. Our results support the conjecture that the linear-t component of the bandwidth at small t/J vanishes as kappa/L2 in the bulk limit, as was anticipated on theoretical grounds; this implies that the propagation of isolated holes is strongly hindered by the staggered magnetization of the ground state. For this initial study we used a very simple trial wave function for importance sampling; it should be possible to obtain comparably accurate Monte Carlo results for band structure at appreciably larger t/J with improved importance sampling. C1 OAK RIDGE NATL LAB, CTR COMPUTAT INTENS PHYS, OAK RIDGE, TN 37831 USA. UNIV TENNESSEE, DEPT PHYS, KNOXVILLE, TN 37996 USA. UNIV TENNESSEE, CTR COMP, KNOXVILLE, TN 37996 USA. RP OAK RIDGE NATL LAB, DIV PHYS, OAK RIDGE, TN 37831 USA. NR 42 TC 4 Z9 4 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11247 EP 11254 DI 10.1103/PhysRevB.47.11247 PG 8 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400029 ER PT J AU BRYANT, PH SMYTH, JF SCHULTZ, S FREDKIN, DR AF BRYANT, PH SMYTH, JF SCHULTZ, S FREDKIN, DR TI MAGNETOSTATIC MODE SPECTRUM OF RECTANGULAR FERROMAGNETIC PARTICLES SO PHYSICAL REVIEW B LA English DT Article ID IRON-GARNET FILMS; RESONANCE AB Approximate methods for obtaining the magnetostatic mode spectrum of thin rectangular samples have been known for some time. However, our experimental results from lithographic arrays of submicron Permalloy particles show that these methods perform relatively poorly if the (in-plane) applied field is not large compared to 4piM(s). We present an improved method for finding the spectrum that takes into account both the elliptical character of the mode precession and sample edge effects. We show that the case of an infinite magnetic strip can be reduced to a one-dimensional eigenvalue problem which we solve numerically, yielding insight into the more difficult rectangular case. Effects of the nonuniform demagnetization field on the spatial patterns and frequencies of the modes are also studied. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. UNIV CALIF SAN DIEGO,DEPT PHYS,LA JOLLA,CA 92093. RP BRYANT, PH (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. NR 12 TC 43 Z9 44 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11255 EP 11262 DI 10.1103/PhysRevB.47.11255 PG 8 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400030 ER PT J AU DAEMEN, LL BULAEVSKII, LN MALEY, MP COULTER, JY AF DAEMEN, LL BULAEVSKII, LN MALEY, MP COULTER, JY TI JOSEPHSON-COUPLED SYSTEMS IN PERPENDICULAR MAGNETIC-FIELDS SO PHYSICAL REVIEW B LA English DT Article ID VORTEX STATE; LAYERED SUPERCONDUCTORS; CRITICAL CURRENTS; VORTICES; TRANSITION; JUNCTIONS; LATTICE; FILMS AB We calculate the critical current along the c axis of a stack of Josephson-coupled layers when the applied magnetic field is perpendicular to the junctions plane. The anisotropy parameter and the Josephson interlayer critical current in the Lawrence-Doniach model are renormalized by the vortex fluctuations and have to be determined self-consistently. This leads to the existence of a decoupling phase transition in the (H, T) plane. The decoupling phase transition is first order for moderate (bare) anisotropies and second order for large anisotropies. We consider the effect of pinning centers and show that only strong disorder affects the critical current. Application of the formalism to single crystals, tapes, and films of highly anisotropic, layered superconductors is discussed. The magnetic field and temperature dependence of the critical current in tapes is calculated for the brick-wall model. C1 LOS ALAMOS NATL LAB,CTR SUPERCONDUCTIV TECHNOL,LOS ALAMOS,NM 87545. RP DAEMEN, LL (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. RI Lujan Center, LANL/G-4896-2012 NR 31 TC 120 Z9 120 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11291 EP 11301 DI 10.1103/PhysRevB.47.11291 PG 11 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400034 ER PT J AU LI, Q SUENAGA, M KIMURA, T KISHIO, K AF LI, Q SUENAGA, M KIMURA, T KISHIO, K TI REVERSIBLE MAGNETIC-PROPERTIES OF (LA1-XSRX)2CUO4 SINGLE-CRYSTALS WITH 0.05-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-0.10 SO PHYSICAL REVIEW B LA English DT Article ID PENETRATION DEPTH; ELECTRONIC STATES; TRANSITION; SUPERCONDUCTIVITY; LA1.85SR0.15CUO4; YBA2CU3O7-DELTA; LA2-XSRXCUO4-Y; BI2SR2CACU2O8; TRANSPORT; FIELDS AB Systematic magnetization measurements were made to study reversible magnetic properties of a series of high-quality, large single crystals of (La1-xSrx)2CuO4 over a composition range of x = 0.05-0.10, with magnetic fields parallel to the c axis. A method of data analysis, based on the variational model developed by Hao and Clem, was used for the determination of various superconducting parameters of this family. We fit the temperature dependence of the thermodynamic critical field H(c)(T) data, which was obtained in the temperature region where the thermodynamic fluctuation is insignificant, with the BCS or an empirical function for H(c)(T). We found that a crystal (x = 0.077), which has the highest T(c) (congruent-to 35.0 K), shows a maximum in the value of H(c)(0) (= 2510+/-80 Oe) and a minimum in the value of lambda(ab)(0) (= 2545+/-40 angstrom) for the range of x that we have studied. We also observed rather close values of coherence length in the ab plane [xi(ab)(0) approximately 32 angstrom] for all (La1-xSrx)2CuO4 single crystals that we studied. C1 UNIV TOKYO, DEPT IND CHEM, BUNKYO KU, TOKYO 113, JAPAN. RP LI, Q (reprint author), BROOKHAVEN NATL LAB, DIV MAT SCI, UPTON, NY 11973 USA. NR 33 TC 34 Z9 34 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11384 EP 11390 DI 10.1103/PhysRevB.47.11384 PG 7 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400046 ER PT J AU BUZDIN, AI AF BUZDIN, AI TI MULTIPLE-QUANTA VORTICES AT COLUMNAR DEFECTS SO PHYSICAL REVIEW B LA English DT Article AB The possibility of the formation of multiple-quanta vortices on columnar defects (CD's) produced by ion irradiation is discussed. It is shown that the upper-critical field for localized superconductivity near CD's depends nonmonotonously on the CD radius. RP BUZDIN, AI (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Buzdin, Alexander/I-6038-2013 NR 8 TC 112 Z9 113 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11416 EP 11419 DI 10.1103/PhysRevB.47.11416 PG 4 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400050 ER PT J AU DELARUBIA, TD CARO, A SPACZER, M AF DELARUBIA, TD CARO, A SPACZER, M TI KINETICS OF RADIATION-INDUCED DISORDERING OF A3B INTERMETALLIC COMPOUNDS - A MOLECULAR-DYNAMICS-SIMULATION STUDY SO PHYSICAL REVIEW B LA English DT Note ID DISPLACEMENT CASCADES; THERMAL SPIKES; METALS; CU AB Intermetallic compounds are susceptible to disordering when exposed to irradiation with energetic particles. However, the atomistic mechanisms of this process are not fully understood. We present molecular-dynamics studies of the kinetics of disordering induced by 5-keV energetic displacement cascades in Cu3Au and Ni3Al. Our results show that the underlying crystalline structure is lost in the local region of the cascade core. However, kinetic constraints imposed by the fast quenching rate of the cascade region prevent a complete loss of chemical short-range order from occurring. After the cascade energy dissipates, the Bragg-Williams long-range-order parameter in the central region is found to have a value near zero. The shape of the interface between the cascade-induced disordered region and the surrounding ordered lattice is shown to depend on the ordering energy of the irradiated compound. C1 PAUL SCHERRER INST,CH-5232 VILLIGEN,SWITZERLAND. RP DELARUBIA, TD (reprint author), LAWRENCE LIVERMORE NATL LAB,L-644,LIVERMORE,CA 94550, USA. NR 21 TC 50 Z9 50 U1 2 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11483 EP 11486 DI 10.1103/PhysRevB.47.11483 PG 4 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400059 ER PT J AU ZHANG, LZ WANG, XQ AF ZHANG, LZ WANG, XQ TI CRITICAL EXPONENTS FOR THE 3-DIMENSIONAL SUPERFLUID BOSE-GLASS PHASE-TRANSITION SO PHYSICAL REVIEW B LA English DT Note ID CRITICAL-BEHAVIOR; LOCALIZATION; FILMS AB The critical phenomenon of the zero-temperature superfluid-Bose-glass phase transition for hard-core bosons on a three-dimensional disordered lattice is studied using a quantum real-space renormalization-group method. The correlation-length exponent nu and the dynamic exponent z are computed. The critical exponent z is found to be 2.5 for compressible states and 1.3 for incompressible states. The exponent nu is shown to be insensitive to z as that in the two-dimensional case, and has a value roughly equal to 1. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. CLARK ATLANTA UNIV,CTR THEORET STUDIES PHYS SYST,ATLANTA,GA 30314. RP ZHANG, LZ (reprint author), UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996, USA. NR 22 TC 7 Z9 7 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11518 EP 11520 DI 10.1103/PhysRevB.47.11518 PG 3 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400069 ER PT J AU CRAWFORD, MK HARLOW, RL MCCARRON, EM FARNETH, WE HERRON, N CHOU, H COX, DE AF CRAWFORD, MK HARLOW, RL MCCARRON, EM FARNETH, WE HERRON, N CHOU, H COX, DE TI STRUCTURAL PHASE-TRANSITIONS AND WEAK FERROMAGNETISM IN LA2-XNDXCUO4+DELTA SO PHYSICAL REVIEW B LA English DT Note ID LATTICE INSTABILITIES; NEUTRON-SCATTERING; LA2-XBAXCUO4; LA2CUO4; SUPERCONDUCTIVITY AB When cooled, La2-xNdxCuO4+delta undergoes structural transformations involving tilts of the CuO6 octahedra which can be controlled by varying x and delta. Using synchrotron x-ray and neutron powder diffraction we observe that the transformation from Bmab to Pccn space-group symmetry is accompanied by a 90-degrees copper spin reorientation in the basal plane. Furthermore, a second magnetic transition at lower temperatures yields weak ferromagnetism. These observations may have important implications for the suppression of superconductivity in the P4(2)/nCM phase of La1.875Ba0.125 CuO4. C1 BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP CRAWFORD, MK (reprint author), DUPONT CO INC,POB 80356,WILMINGTON,DE 19880, USA. NR 24 TC 34 Z9 34 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 17 BP 11623 EP 11626 DI 10.1103/PhysRevB.47.11623 PG 4 WC Physics, Condensed Matter SC Physics GA LC514 UT WOS:A1993LC51400096 ER PT J AU PECHARSKY, VK HYUN, OB GSCHNEIDNER, KA AF PECHARSKY, VK HYUN, OB GSCHNEIDNER, KA TI UNUSUAL MAGNETIC-PROPERTIES OF THE HEAVY-FERMION COMPOUND CECOGE3 SO PHYSICAL REVIEW B LA English DT Article ID BANISN3; SYSTEMS; RH; IR; RU; OS AB Heat capacity, magnetization, and electrical resistivity measurements were carried out on CeCoGe3 and LaCoGe3. CeCoGe3 was found to be a heavy-fermion system with gamma = 111 mJ/mole Ce K2. Two magnetic transitions were found at approximately 21 and approximately 18 K in the absence of a magnetic field. The upper ordering temperature is believed to be a transition from the paramagnetic state to a c-axis ferrimagnetic (FERRI) state, which in turn transforms a colinear antiferromagnetic (AF) state at approximately 18 K. The AF phase undergoes an irreversible phase transition to the FERRI state under an applied magnetic field. Consequently, magnetic glasslike behaviors such as thermal and magnetic hysteresis, frozen moment, and magnetic relaxation were observed. A nonhysteretic metamagnetic transition to a c-axis ferromagnet (FERRO) was observed at high magnetic fields. The critical spin-flip field, H(m), increases in the FERRI state, and decreases in the AF state as temperature decreases. The magnetic data also suggest that the Ce moments in the ab plane are antiferromagnetically aligned in all three magnetic phases. The existence of both ferromagnetism and antiferromagnetism implies that there may be close competition of ferromagnetic and antiferromagnetic exchange interactions between Ce moments leading to possible spin frustration. C1 LVOV IVAN FRANKO STATE UNIV,DEPT INORGAN CHEM,LVOV 290005,UKRAINE. IOWA STATE UNIV SCI & TECHNOL,DEPT MAT SCI & ENGN,AMES,IA 50011. RP PECHARSKY, VK (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 23 TC 62 Z9 62 U1 3 U2 13 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 11839 EP 11847 DI 10.1103/PhysRevB.47.11839 PG 9 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900024 ER PT J AU FISHMAN, RS LIU, SH AF FISHMAN, RS LIU, SH TI MAGNETIC-STRUCTURE AND PARAMAGNETIC DYNAMICS OF CHROMIUM AND ITS ALLOYS SO PHYSICAL REVIEW B LA English DT Article ID AT-PERCENT-V; SCATTERING AB Using mean-field theory, we study the dynamics of chromium and its alloys above the Neel temperature T(N). Starting with a three-band model of chromium, we recover the two-band model originally developed by Sato and Maki (SM). From the poles of the transverse spin susceptibility, we calculate the wave vector and Neel temperature of the spin-density-wave (SDW) state. Like SM, we find that the SDW is commensurate with the lattice when the energy mismatch z0 between the electron and hole Fermi surfaces is smaller than the critical value z0* almost-equal-to 365 meV, which may be achieved with the addition of a small fraction of manganese impurities, as observed experimentally. In the incommensurate state above z0*, the susceptibility contains two peaks on either side of the wave vector G/2=2=2pi/a for small frequency and close to T(N). In the commensurate state below z0*, the susceptibility contains only a single peak at G/2. Because z0* decreases with the damping energy GAMMA, this central peak may split into sidepeaks with the addition of isoelectric impurities such as molybdenum or tungsten. As GAMMA increases, z0* reaches a minimum value of about 185 meV. When z0 is below this minimum value, the SDW is always commensurate for any value of the damping. If GAMMA exceeds the critical damping GAMMA(cr), then the Neel temperature vanishes but the susceptibility still contains peaks near the wave vectors of the SDW with GAMMA=0. In agreement with experiments by Fawcett et al., we find that the elastic-scattering cross section for paramagnetic chromium alloys vanishes at T=0. We also predict that the elastic-scattering cross section reaches a maximum at a temperature which increases with GAMMA. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. RP FISHMAN, RS (reprint author), N DAKOTA STATE UNIV,DEPT PHYS,FARGO,ND 58105, USA. RI Fishman, Randy/C-8639-2013 NR 20 TC 13 Z9 13 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 11870 EP 11882 DI 10.1103/PhysRevB.47.11870 PG 13 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900028 ER PT J AU WANG, ZQ LI, XP LEE, DH AF WANG, ZQ LI, XP LEE, DH TI SPIN-TRIPLET SOLITONS IN THE ONE-DIMENSIONAL SYMMETRICAL KONDO-LATTICE SO PHYSICAL REVIEW B LA English DT Article ID ENERGY-GAP; CENISN AB By analyzing the Gutzwiller-projected, self-consistent mean-field solutions we demonstrate that for all coupling strengths of the half-filled, one-dimensional Kondo lattice (1) the spin excitations are local triplets, (2) the charge gap is greater than the spin gap, and (3) doping by Kondo holes induces residual spin-1/2 local moments. The implications of these results on a number of experiments and their relevance to the ''Kondo insulators'' will be discussed. C1 IBM CORP,THOMAS J WATSON RES CTR,DIV RES,YORKTOWN HTS,NY 10598. RUTGERS UNIV,SERIN PHYS LAB,PISCATAWAY,NJ 08854. RP WANG, ZQ (reprint author), LOS ALAMOS NATL LAB,MS K765,LOS ALAMOS,NM 87545, USA. NR 20 TC 24 Z9 24 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 11935 EP 11939 DI 10.1103/PhysRevB.47.11935 PG 5 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900035 ER PT J AU YONEMITSU, K BISHOP, AR LORENZANA, J AF YONEMITSU, K BISHOP, AR LORENZANA, J TI DOPING STATES IN THE 2-DIMENSIONAL 3-BAND PEIERLS-HUBBARD MODEL SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTIVITY; CHARGE-TRANSFER EXCITATIONS; METAL-INSULATOR-TRANSITION; HIGH-TC SUPERCONDUCTIVITY; COLLECTIVE EXCITATIONS; BAG MECHANISM; HARTREE-FOCK; SPIN; PHONONS; OXIDES AB Doping states in a two-dimensional three-band Peierls-Hubbard model for the copper oxides are investigated with inhomogeneous Hartree-Fock (HF) and random-phase approximations. The doping states are sensitive to small changes of interaction parameters because they easily change local energy balance between different interactions around added holes. For the parameter values derived from constrained-density-functional methods for the copper oxides, added holes form isolated small ferromagnetic polarons. When the parameters are varied around these values, different types of doping states are obtained: For stronger on-site repulsion at Cu sites, larger ferromagnetic polarons are formed, which are qualitatively different from the small polarons; for stronger nearest-neighbor Cu-O repulsion, polarons are clumped or there occurs phase separation into Cu- and O-hole-rich regions; intersite electron-lattice coupling rapidly changes the small polarons by quenching a Cu magnetic moment and locally distorting the lattice in an otherwise undistorted antiferromagnetic background. This is regarded as a rapid crossover from a Zhang-Rice singlet to a covalent molecular singlet, and occurs substantially below a critical strength for destruction of the stoichiometric antiferromagnetic state. However intrasite electron-lattice coupling, in contrast to the intersite coupling, does not dramatically affect the hole-doping states. Doping induces modes in magnetic, optical, and vibronic response functions. Local infrared-active phonon modes are induced in infrared absorption spectra for finite electron-lattice coupling. They are correlated with doping-induced particle-hole excitations observed in optical absorption spectra and in magnetic excitation spectra. These doping-induced particle-hole excitations are associated with the local HF eigenstates in the charge-transfer gap. Each doping state has distinctive excitation spectra in the magnetic, optical, and vibronic channels. In particular, the hole-doping states with small polarons have doping-induced, infrared absorption peaks on the low-frequency side of the stoichiometric peak, while the electron-doping states have them on the high-frequency side. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. SCUOLA INT SUPER STUDI AVANZATI,I-34014 TRIESTE,ITALY. RI Lorenzana, Jose/A-2809-2008 OI Lorenzana, Jose/0000-0001-7426-2570 NR 58 TC 66 Z9 66 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 MAY 1 PY 1993 VL 47 IS 18 BP 12059 EP 12088 DI 10.1103/PhysRevB.47.12059 PG 30 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900048 ER PT J AU SEMENOVSKAYA, S ZHU, YM SUENAGA, M KHACHATURYAN, AG AF SEMENOVSKAYA, S ZHU, YM SUENAGA, M KHACHATURYAN, AG TI TWIN AND TWEED MICROSTRUCTURES IN YBA2CU3O7-DELTA DOPED BY TRIVALENT CATIONS SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-POWDER-DIFFRACTION; SUBSTITUTED YBA2CU3O7-DELTA; NI-AL; YBA2(CU1-XFEX)3O7-DELTA; SUPERCONDUCTIVITY; OXYGEN; CU; YBA2(CU1-XCOX)3O7-DELTA; TRANSFORMATION; SCATTERING AB Computer-simulation techniques and TEM analysis were employed to study the dependence of the twin and tweed microstructures in YBa2Cu3-xMxO7-delta on doping by trivalent atoms (like Fe, Co, or Al). Since the trivalent atoms substituting the bivalent Cu(I) atoms have a greater number of the nearest-neighbor oxygen atoms, it was suggested that doping can be described by the M-O nearest-neighbor attractive interaction. This interaction generates a local oxygen disorder which plays an important role in the formation of the tweed structure. The M-O interaction and the long-range O-O interaction (screened Coulomb and strain induced) were taken into account to simulate the oxygen ordering kinetics. The simulation is based on equations describing the microscopic diffusion of oxygen atoms. The obtained simulated microstructures are in qualitative and even quantitative agreement with electron microscopic observations for YBa2Cu3-xFexO7-delta and with previous electron microscopic data. Both the computer simulations and the TEM results have shown that the usual twin structure, formed through coarsening and refining of the transient tweed structure, is produced at small doping (x less-than-or-equal-to approximately 0.08). At larger x (approximately 0.08 < x < approximately 0.2-0.3), the dopant atoms prevent coarsening and a metastable (or stable) mesoscopic tweed pattern appears. Although the crystal lattice is locally distorted by ultrafine orthorhombic domains forming the tweed pattern, the average crystal lattice determining the diffraction spot pattern is tetragonal. At higher x, the ultrafine orthorhombic domains producing the tweed structure disappear and a disordered tetragonal phase is formed. It is found that doping does not affect the microstructure if the long-range model for the M-O interactions is assumed. C1 BROOKHAVEN NATL LAB,DIV MAT SCI,UPTON,NY 11973. RP SEMENOVSKAYA, S (reprint author), RUTGERS UNIV,DEPT MAT SCI,POB 909,PISCATAWAY,NJ 08855, USA. NR 39 TC 48 Z9 48 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 12182 EP 12189 DI 10.1103/PhysRevB.47.12182 PG 8 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900060 ER PT J AU INUI, M HARSHMAN, DR AF INUI, M HARSHMAN, DR TI MUON-SPIN RELAXATION AND MAGNETIC-FLUX LINES IN THE MIXED-STATE HIGH-TEMPERATURE SUPERCONDUCTORS SO PHYSICAL REVIEW B LA English DT Article ID PENETRATION DEPTH; SINGLE-CRYSTALS; BI2SR2CACU2O8+DELTA; DEPENDENCE AB We discuss the use of the muon-spin-relaxation (mu+SR) technique in studying the flux lines in superconductors. We argue that their dynamics may be studied if the thermal energies are sufficiently large compared to the vortex-lattice stiffness and pinning. In this context, we analyze a recent set of mu+SR data taken on Bi2Sr2CaCu2O8+delta. The data indicate flux motion below T(c). The consequences of the disorder in the flux-line configuration are also discussed. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. RP INUI, M (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,LOS ALAMOS,NM 87545, USA. NR 20 TC 14 Z9 14 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 12205 EP 12213 DI 10.1103/PhysRevB.47.12205 PG 9 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900063 ER PT J AU PRELOVSEK, P SEGA, I BONCA, J LIN, HQ CAMPBELL, DK AF PRELOVSEK, P SEGA, I BONCA, J LIN, HQ CAMPBELL, DK TI ONE-DIMENSIONAL T-J AND HUBBARD MODELS IN A STAGGERED FIELD SO PHYSICAL REVIEW B LA English DT Article ID CORRELATION EXPONENTS; SINGLE-HOLE; FERMI GAS; ANTIFERROMAGNET; EXCITATIONS; INSULATORS; SYSTEMS AB The influence of the staggered magnetic field h on properties of the one-dimensional t-J and Hubbard models with nearly half-filled bands are studied. Using the exact diagonalization method for small systems as well as analytical approaches possible in the anisotropic model and for h >> t, we determine the phase diagram of the t-J-h model at low doping, which displays three different regimes: the phase with repelling holes for J < J(c), the phase with paired holes for J(c) < J < J(s) and the phase separation for J > J(s). Employing for h not-equal 0 the analogy with the universal behavior of one-dimensional interacting fermions within the Luther-Emery regime, we calculate the charge exponent K(rho), which can be K(rho) > 1 in the pairing regime, indicating dominant superconducting fluctuations. An analogous analysis, in particular the perturbation expansion in t/h, performed for the Hubbard t-U-h model shows a phase of stable hole pairs for U < U(c). Again K(rho) seems to approach a nonuniversal value at half-filling. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. UNIV ILLINOIS, URBANA, IL 61801 USA. RP PRELOVSEK, P (reprint author), UNIV LJUBLJANA, J STEFAN INST, LJUBLJANA 6111, SLOVENIA. NR 33 TC 8 Z9 8 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 12224 EP 12234 DI 10.1103/PhysRevB.47.12224 PG 11 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900065 ER PT J AU SALAMON, D LIU, R KLEIN, MV GROENKE, DA POEPPELMEIER, KR DABROWSKI, B HAN, PD PAYNE, DA AF SALAMON, D LIU, R KLEIN, MV GROENKE, DA POEPPELMEIER, KR DABROWSKI, B HAN, PD PAYNE, DA TI RAMAN-SCATTERING RESULTS FROM Y1-XCAXSR2CU2GAO7 SO PHYSICAL REVIEW B LA English DT Article ID SPIN FLUCTUATIONS; SUPERCONDUCTORS; CUPRATE AB We present a Raman-scattering study of Y1-xCaxSr2Cu2GaO7 for both the x = 0 parent compound and doped compositions with x = 0.25 and x = 0.40. Extrapolation from YBa2Cu3O7-d and other cuprates allows us to assign many of the Raman-active phonon modes in the x = 0 material, as well as identify a two-magnon scattering peak, a second-order phonon scattering peak, and a Raman continuum out to 4000 cm-1. Despite compositional inhomogeneities, the doped superconducting samples show some of the same low-energy phonon features as the x = 0 material. There is, however, a doping-dependent shift in the positions of features in the 500-700 cm-1 range, possibly due to Ca locating on Sr sites instead of Y sites. The relative intensities of the phonon peaks in the doped material are also changed from the insulator (x = 0), suggesting that a resonant Raman phenomenon is occurring. The temperature-dependent spectra show what appears to be a superconducting dip in the background intensity, but the low superconducting fractions in these samples make this difficult to verify. The doped material also has a Raman continuum out to 4000 cm-1 just as in the x = 0 samples, but with the two-magnon and second-order phonon scattering peaks significantly reduced in intensity. This may be a result of changes in the long-range ordering, or another manifestation of the same resonance phenomena occurring at lower energies. Single-crystal samples of the doped material Y1-xCaxSr2Cu2GaO7 are necessary for a more conclusive Raman study. C1 UNIV ILLINOIS,MAT RES LAB,URBANA,IL 61801. NO ILLINOIS UNIV,DEPT PHYS,DE KALB,IL 60115. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. UNIV ILLINOIS,DEPT MAT SCI & ENGN,URBANA,IL 61801. RP SALAMON, D (reprint author), UNIV ILLINOIS,DEPT PHYS,1110 W GREEN ST,URBANA,IL 61801, USA. NR 25 TC 6 Z9 6 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 12242 EP 12247 DI 10.1103/PhysRevB.47.12242 PG 6 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900067 ER PT J AU MILLER, D RICHARDS, PL AF MILLER, D RICHARDS, PL TI USE OF KRAMERS-KRONIG RELATIONS TO EXTRACT THE CONDUCTIVITY OF HIGH-TC SUPERCONDUCTORS FROM OPTICAL-DATA SO PHYSICAL REVIEW B LA English DT Note ID YBA2CU3O7-DELTA THIN-FILM; INFRARED ABSORPTIVITY; PENETRATION DEPTH; TEMPERATURE; MICROWAVE; CRYSTALS; LOSSES; GAP AB In principle the conductivity of the cuprate superconductors can be obtained from reflectivity measurements using the Kramers-Kronig-transform technique. However, at low temperatures and for frequencies below approximately 300 cm-1 the reflectivities of materials such as YBa2Cu3O7 are close to unity. Uncertainty in the precise signal level corresponding to unity reflectivity and a lack of knowledge of the reflectivity below the lowest measured frequency cause this method to become unreliable. To address this problem we have used a bolometric technique and a resonant technique to obtain accurate submillimeter and microwave data for the residual losses in epitaxial thin films of YBa2Cu3O7 at low temperatures. The Kramers-Kronig analysis of our data is in good agreement with results from fitting our data to simple weakly coupled grain and two-fluid models for the a-b plane conductivity. However, below 450 cm-1 it is in disagreement with some published results of other workers obtained from Kramers-Kronig analysis of reflectivity data. To understand this discrepancy we analyze how the conductivity determined by the Kramers-Kronig-transform technique depends on some commonly used low-frequency extrapolations of reflectivity data, C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP MILLER, D (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. NR 21 TC 19 Z9 19 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 12308 EP 12311 DI 10.1103/PhysRevB.47.12308 PG 4 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900083 ER PT J AU DELEON, JM BATISTIC, I BISHOP, AR CONRADSON, SD RAISTRICK, I AF DELEON, JM BATISTIC, I BISHOP, AR CONRADSON, SD RAISTRICK, I TI COMMENT ON AXIAL OXYGEN-CENTERED LATTICE INSTABILITIES IN YBA2CU3O7 - AN APPLICATION OF THE ANALYSIS OF EXTENDED X-RAY-ABSORPTION FINE-STRUCTURE IN ANHARMONIC SYSTEMS - REPLY SO PHYSICAL REVIEW B LA English DT Letter ID SUPERCONDUCTING TRANSITION; ACTIVE PHONONS; RBA2CU3O7-DELTA; SPECTROSCOPY; TEMPERATURE; GAP; TC AB We assert that the one-site Cu(1)-O(4) model, suggested in the Comment by Thomsen and Cardona [Phys. Rev. B 47, 12 320 (1993)] is inconsistent with polarized x-ray-absorption fine-structure and diffraction results. We also show that the two-site Cu(1)-O(4) distribution is not inconsistent with optical measurements, although a rigid double-well modeling of this distribution is [Phys. Rev. Lett. 68, 3236 (1992)]. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. NR 29 TC 16 Z9 16 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 12322 EP 12324 PG 3 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900087 ER PT J AU CANFIELD, PC THOMPSON, JD CHEONG, SW RUPP, LW AF CANFIELD, PC THOMPSON, JD CHEONG, SW RUPP, LW TI EXTRAORDINARY PRESSURE-DEPENDENCE OF THE METAL-TO-INSULATOR TRANSITION IN THE CHARGE-TRANSFER COMPOUNDS NDNIO3 AND PRNIO3 SO PHYSICAL REVIEW B LA English DT Note ID TEMPERATURE AB The pressure dependence of the metal-to-insulator transition in NdNiO3 and PrNiO3 has been studied up to applied hydrostatic pressures of 16 kbar. In both cases the first-order metal-to-insulator phase transition is extremely sensitive to pressure, with 15.1 kbar suppressing the transition from 196 to 103 K in NdNiO3 and 14.1 kbar suppressing the transition from 130 to below 1.5 K in PrNiO3. Analysis of the data within the framework of charge-transfer gap insulators leads to the prediction that the primary effect of pressure is to straighten the Ni-O-Ni bond angle, leading to a broadening of the lower, oxygen-like valence band. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. RP CANFIELD, PC (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Canfield, Paul/H-2698-2014 NR 15 TC 121 Z9 121 U1 2 U2 19 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 12357 EP 12360 DI 10.1103/PhysRevB.47.12357 PG 4 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900096 ER PT J AU TAN, ZQ HEALD, SM CHEONG, SW COOPER, AS MOODENBAUGH, AR AF TAN, ZQ HEALD, SM CHEONG, SW COOPER, AS MOODENBAUGH, AR TI NATURE OF HOLE DOPING IN ND2NIO4 AND LA2NIO4 - COMPARISON WITH LA2CUO4 SO PHYSICAL REVIEW B LA English DT Note ID X-RAY-ABSORPTION; ELECTRONIC-STRUCTURE; LA2-XSRXCUO4; SPECTRA; SYSTEM; STATES; PLANE AB To elucidate the hole doping mechanism, we have systematically studied the Ni and Cu K-edge x-ray-absorption spectra in doped Nd2NiO4, La2NiO4, and La2CuO4. We find a significant difference in the character of the doped hole between the nickelates and cuprate. We observe that both strontium substitution and introduction of excess oxygen lead to a shift of the Ni absorption edge to higher energies, by nearly 3 eV in NaSrNiO4. This result demonstrates that the doped holes, in addition to the O 2p character, have a substantial amount of Ni 3d character (30-40 %). The intensity of the 1s-3d transition increases upon doping, consistent with increasing number of d holes. In contrast, the Cu absorption edge in the doped cuprate is shifted by much smaller amounts, indicative of a lower amount of Cu 3d character for the doped hole. The strongly mixed Ni 3d and O 2p character of the doped hole distinguishes the electronic structure of the nickelate from that of the cuprate. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. RP TAN, ZQ (reprint author), BROOKHAVEN NATL LAB,AT&T BELL LABS,BLDG 510E,UPTON,NY 11973, USA. OI Moodenbaugh, Arnold/0000-0002-3415-6762 NR 24 TC 34 Z9 34 U1 0 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 12365 EP 12368 DI 10.1103/PhysRevB.47.12365 PG 4 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900098 ER PT J AU WELP, U FLESHLER, S KWOK, WK DOWNEY, J CRABTREE, GW CLAUS, H ERB, A MULLERVOGT, G AF WELP, U FLESHLER, S KWOK, WK DOWNEY, J CRABTREE, GW CLAUS, H ERB, A MULLERVOGT, G TI EFFECT OF GOLD IMPURITIES ON THE SUPERCONDUCTING FLUCTUATIONS AND THE UPPER CRITICAL-FIELD OF YBA2CU3O7-DELTA SINGLE-CRYSTALS SO PHYSICAL REVIEW B LA English DT Note ID NORMAL-STATE; UNTWINNED YBA2CU3O7-DELTA; REVERSIBLE MAGNETIZATION; II SUPERCONDUCTORS; TEMPERATURE; ANISOTROPY; TC; BI2SR2CACU2O8; RESISTIVITY; TRANSITION AB High-resolution measurements of the reversible magnetization of YBa2Cu3O7-delta single crystals which were grown in gold crucibles and zirconia crucibles reveal that, within the experimental accuracy, gold impurities do not influence the normal-state susceptibility, the upper critical field, nor the superconducting fluctuation phenomena. C1 UNIV ILLINOIS,DEPT PHYS,CHICAGO,IL 60680. UNIV KARLSRUHE,FAK PHYS,W-7500 KARLSRUHE,GERMANY. RP WELP, U (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Erb, Andreas/F-2210-2010 NR 50 TC 14 Z9 14 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1993 VL 47 IS 18 BP 12369 EP 12372 DI 10.1103/PhysRevB.47.12369 PG 4 WC Physics, Condensed Matter SC Physics GA LD189 UT WOS:A1993LD18900099 ER PT J AU NISIUS, D FORNAL, B BEARDEN, IG BRODA, R MAYER, RH GRABOWSKI, ZW DALY, PJ DAVIDS, CN AHMAD, I BACK, BB BINDRA, K CARPENTER, MP CHUNG, W HENDERSON, D HENRY, RG JANSSENS, RVF KHOO, TL LAURITSEN, T LIANG, Y SORAMEL, F AF NISIUS, D FORNAL, B BEARDEN, IG BRODA, R MAYER, RH GRABOWSKI, ZW DALY, PJ DAVIDS, CN AHMAD, I BACK, BB BINDRA, K CARPENTER, MP CHUNG, W HENDERSON, D HENRY, RG JANSSENS, RVF KHOO, TL LAURITSEN, T LIANG, Y SORAMEL, F TI YRAST ISOMERS IN EXOTIC N=81 NUCLEUS YB-151 STUDIED USING A FRAGMENT MASS ANALYZER SO PHYSICAL REVIEW C LA English DT Article ID PROTON AB Product recoils from the reaction Ru-96 +255 MeV Ni-58 --> 154Hf* were analyzed using the Argonne Fragment Mass Analyzer and transported to a collector foil behind the focal plane, where decay of mus isomers could be studied under low background conditions. The recoils were dispersed in A/q as they traversed the position-sensitive focal-plane detector, and recoil-gamma-ray coincidences could thus be used to assign masses for specific gamma-ray cascades. By use of these methods, yrast isomers with half-lives of 2.6(7) mus and 20(1) mus have been firmly assigned to the exotic N = 81 nucleus 151Yb, and the main features of the isomeric decays have been established. The yrast level structure of 151Yb and lighter N = 81 isotones are compared. C1 INST NUCL PHYS,PL-31342 KRAKOW,POLAND. UNIV PADUA,DIPARTIMENTO FIS,I-35131 PADUA,ITALY. ARGONNE NATL LAB,ARGONNE,IL 60439. VANDERBILT UNIV,NASHVILLE,TN 37235. RP NISIUS, D (reprint author), PURDUE UNIV,W LAFAYETTE,IN 47907, USA. RI Bearden, Ian/M-4504-2014; Carpenter, Michael/E-4287-2015 OI Bearden, Ian/0000-0003-2784-3094; Carpenter, Michael/0000-0002-3237-5734 NR 11 TC 5 Z9 5 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 1929 EP 1932 DI 10.1103/PhysRevC.47.1929 PG 4 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500014 ER PT J AU BATCHELDER, JC MOLTZ, DM OGNIBENE, TJ ROWE, MW CERNY, J AF BATCHELDER, JC MOLTZ, DM OGNIBENE, TJ ROWE, MW CERNY, J TI BETA-DELAYED PROTON DECAY OF SE-65 SO PHYSICAL REVIEW C LA English DT Article ID SEARCH AB The T(Z) = -3/2, A = 4n + 1 nuclide Se-65 produced in the (Ca(Si,3n))-Ca-40-Si-28 reaction has been observed via beta-delayed proton emission. A single proton group at 3.55+/-0.03 MeV has been observed, corresponding to the decay of the T = 3/3 isobaric analog state in As-65 to the ground state of 64Ge. Combining this measurement with a Coulomb displacement energy calculation yields a mass excess for 65Se of - 33.41+/-0.26 MeV. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP BATCHELDER, JC (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720, USA. NR 17 TC 23 Z9 23 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2038 EP 2042 DI 10.1103/PhysRevC.47.2038 PG 5 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500028 ER PT J AU MADSEN, VA BAUER, RW ANDERSON, JD BROWN, VR POHL, BA POPPE, CH STAMER, S MORDHORST, E SCHOBEL, W GRIMES, SM AF MADSEN, VA BAUER, RW ANDERSON, JD BROWN, VR POHL, BA POPPE, CH STAMER, S MORDHORST, E SCHOBEL, W GRIMES, SM TI THEORETICAL TREATMENT OF ANALOG (P, N) CROSS-SECTIONS FOR ODD NUCLEI - APPLICATION TO MEASUREMENTS OF PD-105 AT 26 MEV SO PHYSICAL REVIEW C LA English DT Article ID INELASTIC-SCATTERING; EFFECTIVE CHARGES; POLARIZATION; ISOTOPES AB Differential cross sections for the (p,n) reaction to the ground-state and excited-state analogs of Pd-105 have been measured at a proton bombarding energy of 26 MeV. Both the magnitude and the angular distribution of the cross sections for the analog states are found to follow the same general trend observed for the even-even palladium isotopes. Contributions to the analog transition on odd-A targets from spin-flip, higher multipoles, collective admixtures, and multistep processes are calculated and are found to be of order 1/(N - Z) or smaller, as compared to the (N - Z) scaling expected for the Fermi transition. This is in agreement with our experimental data which show that the analog cross section scales as (N - Z) relative to the neighboring nuclei. Among the excited analog states within the first MeV of excitation, the levels at 0.44 and 0.78 MeV were the most strongly populated. This is consistent with a two-step mechanism involving inelastic scattering and charge exchange, since these two states are also known to have the largest B (E2) values. Although the small predicted magnitude of the additional contributions for nonzero spin targets agrees nicely with the present measurements for Pd-105, it leaves the puzzle as to why cross sections for odd isotopes for titanium and molybdenum measured in previous work were found to be larger than corresponding cross sections for adjacent even isotopes. C1 UNIV HAMBURG,INST EXPTL PHYS 1,W-2000 HAMBURG 13,GERMANY. OREGON STATE UNIV,CORVALLIS,OR 97331. OHIO UNIV,ATHENS,OH 45701. RP MADSEN, VA (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 31 TC 0 Z9 0 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2077 EP 2092 DI 10.1103/PhysRevC.47.2077 PG 16 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500032 ER PT J AU KOEHLER, PE GRAFF, SM OBRIEN, HA GLEDENOV, YM POPOV, YP AF KOEHLER, PE GRAFF, SM OBRIEN, HA GLEDENOV, YM POPOV, YP TI CL-36 (N,P)S-36 CROSS-SECTION FROM 25 MEV TO 800 KEV AND THE NUCLEOSYNTHESIS OF THE RARE ISOTOPE S-36 SO PHYSICAL REVIEW C LA English DT Article ID S-PROCESS; RANGE AB We have measured the (Cl(n,p)S)-Cl-36-S-36 cross section from thermal energy to approximately 800 keV. Parameters for eight resonances between 900 eV and 70 keV were determined in a multilevel fit to our data which also included information from published (S(p, gamma)Cl)-S-36-Cl-37 measurements. The (Cl(n,p)S)-Cl-36-S-36 reaction can play a critical role in the production of the rare isotope S-36 in explosive nucleosynthesis and s-process calculations. The astrophysical rate for this reaction was calculated from our measured cross sections and was found to be significantly smaller than the theoretical rate used in previous nucleosynthesis calculations. We discuss the impact of this result on the nucleosynthesis of S-36. C1 LOS ALAMOS NATL LAB, DIV PHYS, LOS ALAMOS, NM 87545 USA. DUBNA JOINT NUCL RES INST, NEUTRON PHYS LAB, DUBNA, RUSSIA. OI Koehler, Paul/0000-0002-6717-0771 NR 27 TC 15 Z9 15 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 EI 1089-490X J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2107 EP 2112 DI 10.1103/PhysRevC.47.2107 PG 6 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500035 ER PT J AU WANG, L YANG, X RAPAPORT, J GOODMAN, CD FOSTER, CC WANG, Y LINDGREN, RA SUGARBAKER, E MARCHLENSKI, D DELUCIA, S LUTHER, B RYBARCYK, L TADDEUCCI, TN PARK, BK AF WANG, L YANG, X RAPAPORT, J GOODMAN, CD FOSTER, CC WANG, Y LINDGREN, RA SUGARBAKER, E MARCHLENSKI, D DELUCIA, S LUTHER, B RYBARCYK, L TADDEUCCI, TN PARK, BK TI B-10(P,N)C-10 REACTION AT 186 MEV SO PHYSICAL REVIEW C LA English DT Article ID GAMOW-TELLER STRENGTH; INTERMEDIATE ENERGIES; PROTON-SCATTERING; ISOTOPES AB The (B(p,n)C)-B-10-C-10 reaction was studied using the Indiana University Cyclotron Facility (IUCF) neutron time-of-flight facilities at an incident proton energy of 186 MeV between theta(lab) = 0-degrees and theta(lab) = 50-degrees in steps of 5-degrees. The IUCF neutron polarimeter was also used to measure polarization observables at theta(lab) = 0-degrees, 15-degrees, and 20-degrees using an incident transverse polarized proton beam. Data for transitions to excited states in C-10 below 7 MeV are presented. A multipole decomposition analysis is presented for unresolved states up into the continuum. Distorted wave calculations are presented for positive and negative parity transitions which are compared with data to assess spectroscopies of the C-10 excited states. C1 INDIANA UNIV,CYCLOTRON FACIL,BLOOMINGTON,IN 47405. UNIV VIRGINIA,CHARLOTTESVILLE,VA 22901. OHIO STATE UNIV,COLUMBUS,OH 43210. NEW MEXICO STATE UNIV,LAS CRUCES,NM 88003. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP WANG, L (reprint author), OHIO UNIV,ATHENS,OH 45701, USA. NR 35 TC 22 Z9 22 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2123 EP 2134 DI 10.1103/PhysRevC.47.2123 PG 12 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500037 ER PT J AU CHEN, XY TADDEUCCI, TN MCCLELLAND, JB CAREY, TA BYRD, RC RYBARCYK, LJ SAILOR, WC MERCER, DJ PROUT, DL DELUCIA, S LUTHER, B MARCHLENSKI, DG SUGARBAKER, E RAPAPORT, J GULMEZ, E WHITTEN, CA GOODMAN, CD HUANG, W WANG, Y ALFORD, WP AF CHEN, XY TADDEUCCI, TN MCCLELLAND, JB CAREY, TA BYRD, RC RYBARCYK, LJ SAILOR, WC MERCER, DJ PROUT, DL DELUCIA, S LUTHER, B MARCHLENSKI, DG SUGARBAKER, E RAPAPORT, J GULMEZ, E WHITTEN, CA GOODMAN, CD HUANG, W WANG, Y ALFORD, WP TI POLARIZATION TRANSFER IN QUASI-FREE ((P)RIGHT-ARROW,(N)RIGHT-ARROW) REACTIONS AT 495 MEV SO PHYSICAL REVIEW C LA English DT Article ID PROTON-NUCLEUS SCATTERING; INELASTIC ELECTRON-SCATTERING; ISOVECTOR SPIN RESPONSE; INTERMEDIATE ENERGIES; IMPULSE APPROXIMATION; ANALYZING POWER; OBSERVABLES; CA-40; EXCITATION; REGION AB A complete set of polarization-transfer observables has been measured for quasifree (p over arrow pointing right, n over arrow pointing right) reactions on H-2, C-12, and Ca-40 at a bombarding energy of 495 MeV and a laboratory scattering angle of 18-degrees. The data span an energy-loss range from 0 to 160 MeV, with a corresponding momentum transfer range of q(c.m.) = 1.7-1.9 fm-1. The laboratory observables are used to construct partial cross sections proportional to the nonspin response and three orthogonal spin responses. These results are compared to the transverse spin response measured in deep inelastic electron scattering and to nuclear responses based on the random phase approximation. The polarization observables for all three targets are remarkably similar and reveal no evidence for an enhancement of the spin-longitudinal nuclear response relative to the spin-transverse response. These results suggest the need for substantial modifications to the standard form assumed for the residual particle-hole interaction. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. OHIO STATE UNIV,COLUMBUS,OH 43210. UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024. UNIV WESTERN ONTARIO,LONDON N6A 3K7,ONTARIO,CANADA. INDIANA UNIV,CYCLOTRON FACIL,BLOOMINGTON,IN 47405. RP CHEN, XY (reprint author), UNIV COLORADO,BOULDER,CO 80309, USA. RI Gulmez, Erhan/P-9518-2015 OI Gulmez, Erhan/0000-0002-6353-518X NR 59 TC 81 Z9 82 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2159 EP 2177 DI 10.1103/PhysRevC.47.2159 PG 19 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500040 ER PT J AU DEVLIN, M CLINE, D HELMER, KG IBBOTSON, R WU, CY BUTLER, PA CRESSWELL, AJ JONES, GD STOYER, MA RASMUSSEN, JO AF DEVLIN, M CLINE, D HELMER, KG IBBOTSON, R WU, CY BUTLER, PA CRESSWELL, AJ JONES, GD STOYER, MA RASMUSSEN, JO TI SPECTROSCOPY OF PU-238, PU-239 STUDIED BY QUASI-ELASTIC REACTIONS SO PHYSICAL REVIEW C LA English DT Article ID HIGH-SPIN STATES; POPULATION AB The gamma-ray transitions in the ground-state bands of Pu-238 and Pu-239 up to spins 26+ and 51/2+, respectively, were observed in the reaction Pu-239 + Sn-117 (E(c.m.) = 422.9 MeV). Another band in Pu-239 was observed, and is tentatively identified as the high-spin continuation of the 0- octupole excitation built on the 1/2+ ground band in Pu-239. The measured gamma-ray multiplicity and total energy provided data on the population of entrance states in both Pu-238 and Pu-239. The one-neutron-transfer cross section, as determined by the yield of the 6+ --> 4+ transition in Pu-238, was measured to be 65 +/- 25 mb. This transition yield is estimated to represent between 80% and 90% of the total one-neutron-transfer cross section. C1 UNIV LIVERPOOL,OLIVER LODGE LAB,LIVERPOOL L69 3BX,ENGLAND. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP DEVLIN, M (reprint author), UNIV ROCHESTER,NUCL STRUCT RES LAB,ROCHESTER,NY 14627, USA. RI Cresswell, Alan/B-5222-2009; Devlin, Matthew/B-5089-2013 OI Cresswell, Alan/0000-0002-5100-8075; Devlin, Matthew/0000-0002-6948-2154 NR 13 TC 9 Z9 9 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2178 EP 2184 DI 10.1103/PhysRevC.47.2178 PG 7 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500041 ER PT J AU CHINN, CR ELSTER, C THALER, RM AF CHINN, CR ELSTER, C THALER, RM TI ISOSPIN EFFECTS IN ELASTIC PROTON-NUCLEUS SCATTERING SO PHYSICAL REVIEW C LA English DT Article ID FULL-FOLDING-MODEL; INTERMEDIATE ENERGIES; IMPULSE APPROXIMATION; MOMENTUM-TRANSFER; MESON-EXCHANGE; 500-MEV AB Isovector effects in proton-nucleus elastic scattering at medium energies axe studied. The accuracy of the Kerman-McManus-Thaler isospin averaging procedure is found to be very good for nuclei larger than He-4. Studies of Ca-40 and Pb-208 suggest that the surface neutrons may be pulled in somewhat relative to the protons, although uncertainties in the detailed applicability of the present truncation of the multiple scattering treatment render firm conclusions premature. C1 CTR ETUD BRUYERES LE CHATEL,SERV PHYS & TECH NUCL,F-91680 BRUYERES CHATEL,FRANCE. OHIO UNIV,INST NUCL & PARTICLE PHYS,ATHENS,OH 45701. OHIO UNIV,DEPT PHYS,ATHENS,OH 45701. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. CASE WESTERN RESERVE UNIV,CLEVELAND,OH 44106. RI Elster, Charlotte/N-9845-2015 NR 30 TC 7 Z9 7 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2242 EP 2249 DI 10.1103/PhysRevC.47.2242 PG 8 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500051 ER PT J AU CHADWICK, MB YOUNG, PG AF CHADWICK, MB YOUNG, PG TI FESHBACH-KERMAN-KOONIN ANALYSIS OF NB-93 REACTIONS - P-]Q TRANSITIONS AND REDUCED IMPORTANCE OF MULTISTEP COMPOUND EMISSION SO PHYSICAL REVIEW C LA English DT Article ID CROSS-SECTIONS; STATISTICAL-THEORY; BI-209; ENERGY; P,N AB We have implemented multistep compound (MSC) and multistep direct (MSD) preequilibrium theories of Feshbach, Kerman, and Koonin (FKK) for the calculation of nucleon-induced reactions. Unlike most previous analyses, which have concentrated on just one of these multistep mechanisms, we consider both mechanisms as well as subsequent Hauser-Feshbach equilibrium emission, and describe the complete nucleon emission spectra and angular distributions quantum mechanically. We compare theoretical calculations of (n, n') and (n, p) reactions on Nb-93 at energies of 14, 20, and 25.7 MeV with experimental data. Our analysis suggests that the FKK theory should be modified to allow transitions from the MSD to MSC preequilibrium chains, and shows MSC processes to be less important than previously thought. We find that the MSD mechanism dominates preequilibrium emission even for incident neutron energies as low- as 14 MeV. A model to account for preequilibrium flux cascading from the MSD to MSC chain is presented, and we check its validity with a least-squares fit to data which establishes the experimentally observed partitioning between MSD and MSC. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP CHADWICK, MB (reprint author), LAWRENCE LIVERMORE NATL LAB,NUCL DATA GRP,LIVERMORE,CA 94551, USA. NR 41 TC 60 Z9 60 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2255 EP 2265 DI 10.1103/PhysRevC.47.2255 PG 11 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500053 ER PT J AU ESKOLA, KJ GYULASSY, M AF ESKOLA, KJ GYULASSY, M TI COLOR CONDUCTIVITY AND EVOLUTION OF THE MINIJET PLASMA SO PHYSICAL REVIEW C LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; FLUX-TUBE MODEL; TRANSPORT-COEFFICIENTS; HADRONIC REACTIONS; PAIR PRODUCTION; ELECTRIC-FIELD; ENERGY AB The early evolution of the gluon plasma produced in ultrarelativistic nuclear collisions is investigated via chromoviscous hydrodynamics. The initial conditions are determined by perturbative QCD minijet production including nuclear shadowing of the parton distributions. The analog of Ohmic heating is shown to damp rapidly any chromoelectric fields in the plasma. In the context of the flux tube models for beam jet fragmentation this damping is shown to suppress pair production processes, decrease transverse energy production, and reduce the quark-gluon chemical equilibration rate. Possible implications for dilepton production are noted. C1 UNIV HELSINKI,HIGH ENERGY PHYS LAB,SF-00014 HELSINKI,FINLAND. COLUMBIA UNIV,DEPT PHYS,PUPIN LAB,NEW YORK,NY 10027. RP ESKOLA, KJ (reprint author), LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720, USA. NR 45 TC 68 Z9 68 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2329 EP 2337 DI 10.1103/PhysRevC.47.2329 PG 9 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500059 ER PT J AU VINEYARD, MF MATEJA, JF BECK, C ATENCIO, SE DENNIS, LC FRAWLEY, AD HENDERSON, DJ JANSSENS, RVF KEMPER, KW KOVAR, DG MAGUIRE, CF PADALINO, SJ PROSSER, FW STEPHANS, GSF TIEDE, MA WILKINS, BD ZINGARELLI, RA AF VINEYARD, MF MATEJA, JF BECK, C ATENCIO, SE DENNIS, LC FRAWLEY, AD HENDERSON, DJ JANSSENS, RVF KEMPER, KW KOVAR, DG MAGUIRE, CF PADALINO, SJ PROSSER, FW STEPHANS, GSF TIEDE, MA WILKINS, BD ZINGARELLI, RA TI ENERGY-DEPENDENCE OF FUSION EVAPORATION-RESIDUE CROSS-SECTIONS IN THE SI-28+C-12 REACTION SO PHYSICAL REVIEW C LA English DT Note ID HEAVY-ION FUSION; COMPOUND NUCLEI; LIGHT; ASYMMETRY; FISSION; LIMIT; C-12 AB Fusion evaporation-residue cross sections for the Si-28 + C-12 reaction have been measured in the energy range 18 less-than-or-equal-to E(c.m.) less-than-or-equal-to 136 MeV using time-of-flight techniques. Velocity distributions of mass-identified reaction products were used to identify evaporation residues and to determine the complete-fusion cross sections at high energies. The data are in agreement with previously established systematics which indicate an entrance-channel mass-asymmetry dependence of the incomplete-fusion evaporation-residue process. The complete-fusion evaporation-residue cross sections and the deduced critical angular momenta are compared with earlier measurements and the predictions of existing models. C1 ARGONNE NATL LAB,DIV EDUC PROGRAMS,ARGONNE,IL 60439. UNIV LOUIS PASTEUR,CTR RECH NUCL,F-67037 STRASBOURG,FRANCE. FLORIDA STATE UNIV,DEPT PHYS,TALLAHASSEE,FL 32306. ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. VANDERBILT UNIV,DEPT PHYS & ASTRON,NASHVILLE,TN 37235. UNIV KANSAS,DEPT PHYS,LAWRENCE,KS 66045. MIT,NUCL SCI LAB,CAMBRIDGE,MA 02139. SUNY COLL GENESEO,DEPT PHYS,GENESEO,NY 14454. RP VINEYARD, MF (reprint author), UNIV RICHMOND,DEPT PHYS,RICHMOND,VA 23173, USA. NR 25 TC 13 Z9 13 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2374 EP 2377 DI 10.1103/PhysRevC.47.2374 PG 4 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500065 ER PT J AU PLOMPEN, AJM HARAKEH, MN HESSELINK, WHA VANTHOF, G KALANTARNAYESTANAKI, N JANSSENS, RVF AHMAD, I BEARDEN, IG CARPENTER, MP KHOO, TL LAURITSEN, T LIANG, Y GARG, U REVIOL, W YE, D AF PLOMPEN, AJM HARAKEH, MN HESSELINK, WHA VANTHOF, G KALANTARNAYESTANAKI, N JANSSENS, RVF AHMAD, I BEARDEN, IG CARPENTER, MP KHOO, TL LAURITSEN, T LIANG, Y GARG, U REVIOL, W YE, D TI LACK OF EVIDENCE FOR A SUPERDEFORMED BAND IN PB-192 SO PHYSICAL REVIEW C LA English DT Note ID GAMMA-RAY; STATES; GD-148 AB An experiment was performed to measure the lifetimes of the states in the superdeformed band reported in 192Pb. No evidence for such a band was found, despite the fact that the experimental conditions were nearly identical to those of an earlier measurement where this band was proposed. The problems and questions encountered in the analysis are described. The arguments presented here indicate that further measurements are needed to establish the existence of a superdeformed band in this nucleus unambiguously. C1 ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556. RP PLOMPEN, AJM (reprint author), FREE UNIV AMSTERDAM,FAC NATUURKUNDE STERRENKUNDE,DE BOELELAAN 1081,1081 HV AMSTERDAM,NETHERLANDS. RI Bearden, Ian/M-4504-2014; Carpenter, Michael/E-4287-2015; Kalantar-Nayestanaki, Nasser/A-3582-2016 OI Bearden, Ian/0000-0003-2784-3094; Carpenter, Michael/0000-0002-3237-5734; Kalantar-Nayestanaki, Nasser/0000-0002-1033-7200 NR 23 TC 9 Z9 9 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2378 EP 2381 DI 10.1103/PhysRevC.47.2378 PG 4 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500066 ER PT J AU KUHNERT, A HENRY, EA WANG, TF BRINKMAN, MJ STOYER, MA BECKER, JA MANATT, DR YATES, SW AF KUHNERT, A HENRY, EA WANG, TF BRINKMAN, MJ STOYER, MA BECKER, JA MANATT, DR YATES, SW TI SEARCH FOR AN M0 TRANSITION IN YB-170 SO PHYSICAL REVIEW C LA English DT Note AB We have examined the suggestion that an MO transition occurs between the 2819.6-keV 0- level of Yb-173 and the 0+ ground state by internal-conversion electron emission. Gamma rays, internal-conversion electrons, and internal e+e- pairs were detected from the beta+ and electron capture decay of two-day Lu-170 (0+). At an upper limit of 2 X 10(-8) electron per Lu-170 decay, no evidence was obtained for MO decay of the 2819.6-keV level of Yb-170 by single-electron emission. C1 UNIV KENTUCKY,LEXINGTON,KY 40506. RP KUHNERT, A (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2386 EP 2388 DI 10.1103/PhysRevC.47.2386 PG 3 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500068 ER PT J AU DOBACZEWSKI, J NAZAREWICZ, W AF DOBACZEWSKI, J NAZAREWICZ, W TI PAIRING CORRELATIONS STUDIED IN THE 2-LEVEL MODEL SO PHYSICAL REVIEW C LA English DT Letter AB We discuss and interpret the numerical results obtained by Zheng, Sprung, and Flocard [Phys. Rev. C 46, 1355 (1992)] in a two-level pairing model. It is shown that a violation of applicability limits of the Kamlah projection method is at the origin of results obtained for a weak pairing strength. C1 OAK RIDGE NATL LAB,JOINT INST HEAVY ION RES,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. UNIV WARSAW,INST THEORET PHYS,PL-00681 WARSAW,POLAND. RP DOBACZEWSKI, J (reprint author), CTR RECH NUCL,F-67037 STRASBOURG,FRANCE. NR 8 TC 36 Z9 36 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1993 VL 47 IS 5 BP 2418 EP 2421 DI 10.1103/PhysRevC.47.2418 PG 4 WC Physics, Nuclear SC Physics GA LD755 UT WOS:A1993LD75500077 ER PT J AU CAMERON, R CANTATORE, G MELISSINOS, AC RUOSO, G SEMERTZIDIS, Y HALAMA, HJ LAZARUS, DM PRODELL, AG NEZRICK, F RIZZO, C ZAVATTINI, E AF CAMERON, R CANTATORE, G MELISSINOS, AC RUOSO, G SEMERTZIDIS, Y HALAMA, HJ LAZARUS, DM PRODELL, AG NEZRICK, F RIZZO, C ZAVATTINI, E TI SEARCH FOR NEARLY MASSLESS, WEAKLY COUPLED PARTICLES BY OPTICAL TECHNIQUES SO PHYSICAL REVIEW D LA English DT Article ID ANOMALOUS MAGNETIC-MOMENT; AXION PRODUCTION; COSMIC AXIONS; LIGHT PSEUDOSCALARS; CP CONSERVATION; SINGLE PHOTONS; NEUTRINO BURST; GAMMA-DECAY; UPPER LIMIT; CONSTRAINTS AB We have searched for light scalar and/or pseudoscalar particles that couple to two photons by studying the propagation of a laser beam (lambda=514 nm) through a transverse magnetic field. A limit of 3.5 X 10(-10) rad was set on a possible optical rotation of the beam polarization for an effective path length of 2.2 km in a 3.25 T magnetic field. We find that the coupling g(alphagammagamma) < 3.6 X 10(-7) GeV-1 at the 95% confidence level, provided m(a) < 10(-3) eV. Similar limits can be set from the absence of ellipticity in the transmitted beam. We also searched for photon regeneration in a magnetic field and found the limit g(alphagammagamma) < 6.7 X 10(-7) GeV-1 for the same range of particle mass. C1 UNIV ROCHESTER,DEPT PHYS & ASTRON,ROCHESTER,NY 14627. BROOKHAVEN NATL LAB,UPTON,NY 11973. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. IST NAZL FIS NUCL,I-34127 TRIESTE,ITALY. UNIV TRIESTE,DIPARTIMENTO FIS,I-34127 TRIESTE,ITALY. RI Semertzidis, Yannis K./N-1002-2013; Ruoso, Giuseppe/G-3075-2015 OI Ruoso, Giuseppe/0000-0001-8140-9382 NR 67 TC 243 Z9 245 U1 1 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1993 VL 47 IS 9 BP 3707 EP 3725 DI 10.1103/PhysRevD.47.3707 PG 19 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA928 UT WOS:A1993LA92800009 ER PT J AU ADAMOVICH, MI AGGARWAL, MM ALEXANDROV, YA ANDREEVA, NP ANSON, ZV ARORA, R AVETYAN, FA BADYAL, SK BASOVA, E BAZAROV, IK BHALLA, KB BHASIN, A BHATIA, VS BOGDANOV, VG BUBNOV, VI BURNETT, TH CAI, X CARSHIEV, DA CHASNICOV, IY CHERNOVA, LP CHERNYAVSKI, MM ELIGBAEVA, GZ EREMENKO, LE GAITINOV, AS GANSSAUGE, ER GARPMAN, S GERASSIMOV, SG GROTE, JG GULAMOV, KG GUPTA, SK GUPTA, VK HECKMAN, HH HUANG, H JACOBSSON, B JUDEK, B KACHROO, S KALYACHKINA, GS KANYGINA, EK KARABOVA, M KHARLAMOV, SP KITROO, S KOSS, T KRASNOV, SA KUMAR, V LAL, P LARIONOVA, VG LEPETAN, VN LIU, LS LOKANATHAN, S LORD, JJ LUKICHEVA, NS LUO, SB MANGOTRA, LK MARUTYAN, NA MASLENNIKOVA, NV MITTRA, IS MOOKERJEE, S NASYROV, SZ NAVOTNY, VS NYSTRAND, J ORLOVA, GI OTTERLUND, I PALSANIA, H PERESADKO, NG PETROV, NV PLYUSCHEV, VA QIAN, WY QIN, YM RANIWALA, R RANIWALA, S RAO, NK RAPPOPORT, VM RHEE, JT SAIDKHANOV, N SALMANOVA, NA SARKISOVA, LG SARKISYAN, VR SHABRATOVA, GS SHAKHOVA, TI SHPILEV, SN SKELDING, D SODERSTROM, K SOLOVIEVA, ZI STENLUND, E SURIN, EL SVECHNIKOVA, LN TOLSTOV, KD TRETYAKOVA, MI TROFIMOVA, TP TULEEVA, U TURSUNOV, BP VOKAL, S WANG, HQ WENG, ZO WILKES, RJ XU, GF ZHANG, DH ZHENG, PY ZHOCHOVA, SI ZHOU, JC ZHOU, DC AF ADAMOVICH, MI AGGARWAL, MM ALEXANDROV, YA ANDREEVA, NP ANSON, ZV ARORA, R AVETYAN, FA BADYAL, SK BASOVA, E BAZAROV, IK BHALLA, KB BHASIN, A BHATIA, VS BOGDANOV, VG BUBNOV, VI BURNETT, TH CAI, X CARSHIEV, DA CHASNICOV, IY CHERNOVA, LP CHERNYAVSKI, MM ELIGBAEVA, GZ EREMENKO, LE GAITINOV, AS GANSSAUGE, ER GARPMAN, S GERASSIMOV, SG GROTE, JG GULAMOV, KG GUPTA, SK GUPTA, VK HECKMAN, HH HUANG, H JACOBSSON, B JUDEK, B KACHROO, S KALYACHKINA, GS KANYGINA, EK KARABOVA, M KHARLAMOV, SP KITROO, S KOSS, T KRASNOV, SA KUMAR, V LAL, P LARIONOVA, VG LEPETAN, VN LIU, LS LOKANATHAN, S LORD, JJ LUKICHEVA, NS LUO, SB MANGOTRA, LK MARUTYAN, NA MASLENNIKOVA, NV MITTRA, IS MOOKERJEE, S NASYROV, SZ NAVOTNY, VS NYSTRAND, J ORLOVA, GI OTTERLUND, I PALSANIA, H PERESADKO, NG PETROV, NV PLYUSCHEV, VA QIAN, WY QIN, YM RANIWALA, R RANIWALA, S RAO, NK RAPPOPORT, VM RHEE, JT SAIDKHANOV, N SALMANOVA, NA SARKISOVA, LG SARKISYAN, VR SHABRATOVA, GS SHAKHOVA, TI SHPILEV, SN SKELDING, D SODERSTROM, K SOLOVIEVA, ZI STENLUND, E SURIN, EL SVECHNIKOVA, LN TOLSTOV, KD TRETYAKOVA, MI TROFIMOVA, TP TULEEVA, U TURSUNOV, BP VOKAL, S WANG, HQ WENG, ZO WILKES, RJ XU, GF ZHANG, DH ZHENG, PY ZHOCHOVA, SI ZHOU, JC ZHOU, DC TI SYSTEMATIC INVESTIGATION OF SCALED FACTORIAL CUMULANT MOMENTS FOR NUCLEUS-NUCLEUS INTERACTIONS SO PHYSICAL REVIEW D LA English DT Article ID HIGH-ENERGY; EMULSION; INTERMITTENCY; COLLISIONS; PROTONS AB We use scaled factorial cumulant moments to analyze pseudorapidity fluctuations in nucleus-nucleus collisions. This approach is similar to the method of scaled factorial moments except that it removes the effects of lower-order correlations upon a given moment. Significant second-order cumulants and cumulant indices (slopes with respect to bin size) are found for all of the interactions studied. These indices are found to have an inverse dependence upon average pseudorapidity particle density. C1 ALMA ATA HIGH ENERGY PHYS INST,ALMA ATA,KAZAKHSTAN. CHINESE ACAD SCI,BEIJING,PEOPLES R CHINA. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. PANJAB UNIV,CHANDIGARH 160014,INDIA. HUNAN EDUC INST,CHANGSHA,PEOPLES R CHINA. JOINT INST NUCL RES,DUBNA,RUSSIA. UNIV RAJASTHAN,JAIPUR 302004,RAJASTHAN,INDIA. UNIV JAMMU,JAMMU 180001,INDIA. SAFARIK UNIV,CS-04180 KOSICE,CZECHOSLOVAKIA. SHANXI NORMAL UNIV,LINFEN,PEOPLES R CHINA. UNIV LUND,S-22101 LUND,SWEDEN. UNIV MARBURG,W-3550 MARBURG,GERMANY. NATL RES COUNCIL CANADA,OTTAWA K1A 0R6,ONTARIO,CANADA. UNIV WASHINGTON,SEATTLE,WA 98195. VG KHLOPIN RADIUM INST,ST PETERSBURG,RUSSIA. TASHKENT NUCL PHYS INST,TASHKENT,UZBEKISTAN. TASHKENT PHYS TECH INST,TASHKENT,UZBEKISTAN. HUA ZHONG NORMAL UNIV,WUHAN,PEOPLES R CHINA. YEREVAN PHYS INST,YEREVAN,ARMENIA. RP ADAMOVICH, MI (reprint author), PN LEBEDEV INST,MOSCOW,RUSSIA. RI Wilkes, R.Jeffrey/E-6011-2013; Gerassimov, Sergei/M-8779-2015; Kharlamov, Sergei/M-9612-2015; Peresadko, Natalia/M-9585-2015; OI Bhasin, Anju/0000-0002-3687-8179 NR 22 TC 16 Z9 16 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1993 VL 47 IS 9 BP 3726 EP 3732 DI 10.1103/PhysRevD.47.3726 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA928 UT WOS:A1993LA92800010 ER PT J AU JADACH, S SKRZYPEK, M WARD, BFL AF JADACH, S SKRZYPEK, M WARD, BFL TI ANALYTICAL RESULTS FOR LOW-ANGLE BHABHA SCATTERING WITH PAIR PRODUCTION SO PHYSICAL REVIEW D LA English DT Article ID QED CORRECTIONS AB We calculate the effect of pair production on the luminosity process of low-angle Bhabha scattering at the SLAC Linear Collider (SLC) and/or CERN e+e- collider LEP. We work in the leading-logarithm approximation to orders alpha2 and alpha3 for the nonsinglet and the singlet contributions, respectively. In particular we calculate the size of the singlet contribution to be below 0.007% for the energy cuts x(c) > 0.1, as was estimated by Jadach and co-workers. In this way, we remove the contribution of such pairs from the theoretical uncertainty in the SLC/LEP luminosity calculation of Jadach and co-workers via the Monte Carlo BHLUMI 2.01 at the precision level of 0.01%. Results are illustrated for typical SLC/LEP acceptance cuts. C1 CERN,DIV THEORY,GENEVA 23,SWITZERLAND. INST NUCL PHYS,PL-31342 KRAKOW,POLAND. STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. RP JADACH, S (reprint author), UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996, USA. NR 24 TC 34 Z9 34 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1993 VL 47 IS 9 BP 3733 EP 3741 DI 10.1103/PhysRevD.47.3733 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA928 UT WOS:A1993LA92800011 ER PT J AU HYER, T AF HYER, T TI SUDAKOV EFFECTS IN P(P)OVER-BAR ANNIHILATION SO PHYSICAL REVIEW D LA English DT Article ID PHOTON-PHOTON COLLISIONS; QCD SUM-RULES; PERTURBATIVE QCD; QUANTUM CHROMODYNAMICS; EXCLUSIVE PROCESSES; FORM-FACTORS; NUCLEON; SCATTERING; PAIRS AB We compute the amplitudes for ppBAR-->gammagamma and ppBAR-->llBAR, taking into account the Sudakov suppression resulting from radiation by isolated partons. Results for the two-photon annihilation process and form factor are presented for several candidate proton distribution amplitudes. Results are also presented for the ratio sigma(ppBAR-->gammagamma)/sigma(ppBAR-->e+e-), which is free of experimental and theoretical normalization uncertainties. Prospects for using these results to constrain the nucleon distribution amplitude are discussed. RP HYER, T (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 23 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1993 VL 47 IS 9 BP 3875 EP 3885 DI 10.1103/PhysRevD.47.3875 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA928 UT WOS:A1993LA92800025 ER PT J AU BHATTACHARYA, T WILLENBROCK, S AF BHATTACHARYA, T WILLENBROCK, S TI PARTICLES NEAR-THRESHOLD SO PHYSICAL REVIEW D LA English DT Article ID RADIATIVE-CORRECTIONS; STANDARD MODEL; Z0 RESONANCE; HIGGS-BOSON; E+E-->MU+MU; WIDTH; MASS AB We propose returning to the definition of the width of a particle in terms of the pole in the particle's propagator. Away from thresholds, this definition of width is equivalent to the standard perturbative definition, up to next-to-leading order; however, near a threshold, the two definitions differ significantly. The width as defined by the pole position provides more information in the threshold region than the standard perturbative definition and, in contrast with the perturbative definition, does not vanish when a two-particle s-wave threshold is approached from below. RP BHATTACHARYA, T (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. RI Bhattacharya, Tanmoy/J-8956-2013 OI Bhattacharya, Tanmoy/0000-0002-1060-652X NR 25 TC 39 Z9 39 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1993 VL 47 IS 9 BP 4022 EP 4027 DI 10.1103/PhysRevD.47.4022 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA928 UT WOS:A1993LA92800042 ER PT J AU NEUBERT, M AF NEUBERT, M TI 2-LOOP CORRECTIONS TO THE ISGUR-WISE FUNCTION IN QCD SUM-RULES SO PHYSICAL REVIEW D LA English DT Article ID EFFECTIVE FIELD-THEORY; DIFFERENTIAL-EQUATIONS METHOD; QUARK EFFECTIVE THEORY; MESON FORM-FACTORS; HEAVY QUARKS; RESONANCE PHYSICS; STATIC QUARK; RENORMALIZATION; LIGHT; DECAYS AB We complete the QCD sum rule analysis of the Isgur-Wise form factor xi(v . v') at next-to-leading order in renormalization-group improved perturbation theory. To this end, the exact result for the two-loop corrections to the perturbative contribution is derived using the heavy quark effective theory. Several techniques for the evaluation of two-loop integrals involving two different types of heavy quark propagators are discussed in detail, among them the methods of integration by parts and differential equations. The order-alpha(s) corrections to the Isgur-Wise function turn out to be small and well under control. At large recoil, they tend to decrease the form factor by 5-10%. RP NEUBERT, M (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 39 TC 41 Z9 41 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1993 VL 47 IS 9 BP 4063 EP 4076 DI 10.1103/PhysRevD.47.4063 PG 14 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA928 UT WOS:A1993LA92800047 ER PT J AU SCHLUMPF, F AF SCHLUMPF, F TI RELATIVISTIC CONSTITUENT QUARK-MODEL OF ELECTROWEAK PROPERTIES OF BARYONS SO PHYSICAL REVIEW D LA English DT Article ID LIGHT-FRONT DYNAMICS; INFINITE-MOMENTUM FRAME; NUCLEON FORM-FACTORS; MAGNETIC-MOMENTS; STATIC PROPERTIES; DECAYS; MESONS; OCTET AB We calculate the electroweak properties of nucleons and hyperons in a relativistic constituent quark model using the light-front formalism. The parameters of the model, namely, the constituent quark mass and the confinement scale, can be uniquely chosen for both the electromagnetic and weak experimental data. A consistent physical picture of the qqq system appears in this work with a symmetric nucleon wave function and an asymmetric hyperon wave function. Only for the strangeness-changing weak decays do we need nontrivial form factors of the constituent quark. RP SCHLUMPF, F (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 37 TC 60 Z9 60 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1993 VL 47 IS 9 BP 4114 EP 4121 DI 10.1103/PhysRevD.47.4114 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA928 UT WOS:A1993LA92800052 ER PT J AU ANDERSON, GW RABY, S DIMOPOULOS, S HALL, LJ AF ANDERSON, GW RABY, S DIMOPOULOS, S HALL, LJ TI PRECISE PREDICTIONS FOR M(T), V(CB), AND TAN-BETA SO PHYSICAL REVIEW D LA English DT Note ID GRAND UNIFIED THEORIES; SOFTLY BROKEN SUPERSYMMETRY; TOP-QUARK-MASS; N=1 SUPERGRAVITY; UNIFICATION; ANGLE; SCALE; SU(5) AB The fermion mass and mixing angle predictions of a recently proposed framework are investigated for large b and tau Yukawa couplings. A new allowed region of parameters is found for this large tanbeta case. The two predictions that are substantially altered, m(t) and tanbeta, are displayed, including the dependence on the input \V(cb)\, m(c), m(b), and alpha(s). A simple restriction on this framework yields an additional prediction for \V(cb)\. If the b, t, and tau Yukawa couplings are equal at the GUT scale then \V(cb)\ is predicted and the top quark mass is constrained to lie in the range m(t) = 179+/-4 GeV. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. STANFORD UNIV,DEPT PHYS,STANFORD,CA 94305. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP ANDERSON, GW (reprint author), OHIO STATE UNIV,DEPT PHYS,COLUMBUS,OH 43210, USA. OI Anderson, Greg/0000-0003-0346-7258 NR 32 TC 87 Z9 87 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1993 VL 47 IS 9 BP R3702 EP R3706 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA928 UT WOS:A1993LA92800008 ER PT J AU DIMOPOULOS, S HALL, LJ RABY, S AF DIMOPOULOS, S HALL, LJ RABY, S TI NEUTRINO MASSES AND MIXING ANGLES IN A PREDICTIVE THEORY OF FERMION MASSES SO PHYSICAL REVIEW D LA English DT Note ID SEARCH AB A framework for predicting charged fermion masses in supersymmetric grand unified theories is extended to make predictions in the neutrino sector. Eight new predictions are made: the two neutrino mass ratios and the three mixing angles and three phases of the weak leptonic mixing matrix. There are three versions of the theory which are relevant for producing MSW neutrino oscillations in the Sun. One of these is preferred by the combined solar neutrino observations. Another will be probed significantly by the searches for nu(mu)nu(tau) oscillations at the NOMAD, CHORUS, and P803 experiments. In this second version nu(tau) could be a significant component of the dark matter in the Universe. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. OHIO STATE UNIV,DEPT PHYS,COLUMBUS,OH 43210. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP DIMOPOULOS, S (reprint author), STANFORD UNIV,DEPT PHYS,STANFORD,CA 94305, USA. NR 23 TC 36 Z9 36 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1993 VL 47 IS 9 BP R3697 EP R3701 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA LA928 UT WOS:A1993LA92800007 ER PT J AU NING, L ECKE, RE AF NING, L ECKE, RE TI ROTATING RAYLEIGH-BENARD CONVECTION - ASPECT-RATIO DEPENDENCE OF THE INITIAL BIFURCATIONS SO PHYSICAL REVIEW E LA English DT Article ID LAYER; INSTABILITY AB The initial bifurcations in rotating Rayleigh-Benard convection are studied in the range of dimensionless rotation rate 0 < OMEGA < 2150 for a cylindrical cell with an aspect ratio of 2.5. We used simultaneous optical-shadowgraph, heat-transport, and local-temperature measurements to determine the stability and characteristics of the azimuthally periodic wall convection state. We also show that the second transition corresponds to the onset of bulk convection. Our results for critical Rayleigh numbers, precession frequencies, and critical mode numbers agree well with theoretical results. The dynamics of the wall convection state can be described by a complex Ginzburg-Landau amplitude equation. C1 LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP NING, L (reprint author), LOS ALAMOS NATL LAB,DIV PHYS,LOS ALAMOS,NM 87545, USA. OI Ecke, Robert/0000-0001-7772-5876 NR 22 TC 33 Z9 33 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1993 VL 47 IS 5 BP 3326 EP 3333 DI 10.1103/PhysRevE.47.3326 PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA LF067 UT WOS:A1993LF06700041 ER PT J AU TOMASEL, FG ROCCA, JJ CORTAZAR, OD SZAPIRO, BT LEE, RW AF TOMASEL, FG ROCCA, JJ CORTAZAR, OD SZAPIRO, BT LEE, RW TI PLASMA-DENSITY EVOLUTION IN COMPACT POLYACETAL CAPILLARY DISCHARGES SO PHYSICAL REVIEW E LA English DT Article ID SOFT-X-RAY; LINE-SHAPES; C-IV; TRANSITIONS; EMISSION; VACUUM; MODEL; GAIN; IONS AB We have measured the temporal evolution of the electron density of plasmas produced in polyacetal capillaries with diameters between 0.5 and 1.5 mm excited by 110-ns full-width-at-half-maximum discharge pulses with currents between 13 and 42 kA. The electron density was determined from Stark-broadened line profiles of the 4f-3d O VI transition taking into account opacity effects. The electron density was found to increase continuously during the rise of the current pulse, and to decrease near the end of the current pulse, when a drop in plasma temperature causes the degree of ionization of the plasma to decrease. The peak plasma density in a 1-mm capillary excited by a 24-kA pulse was measured to be 5 X 10(19) cm-3. The plasma density was observed to increase linearly with discharge energy from 7.5 X 10(18) cm-3 for a 5-J discharge to 5 X 10(19) cm-3 for a 30-J discharge in a 1.5-mm-diam. capillary. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP TOMASEL, FG (reprint author), COLORADO STATE UNIV,DEPT ELECT ENGN,FT COLLINS,CO 80523, USA. RI Cortazar, Osvaldo/H-7565-2015 OI Cortazar, Osvaldo/0000-0002-3930-2685 NR 24 TC 22 Z9 22 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1993 VL 47 IS 5 BP 3590 EP 3597 DI 10.1103/PhysRevE.47.3590 PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA LF067 UT WOS:A1993LF06700068 ER PT J AU MARSH, GE AF MARSH, GE TI HELICITY, TOPOLOGY, AND FORCE-FREE FIELDS SO PHYSICAL REVIEW E LA English DT Article ID NUMBER AB Concepts from topology are increasingly finding utility in magnetohydrodynamics. This paper gives an example of how the connectivity of the domain and the gauge freedom of the vector potential can play an important role in computing the helicity of twisted magnetic fields used in several areas of astro-physics, particularly solar physics. By computing the relative helicity of a simple magnetic field configuration used to model solar prominences, it is shown that helicity can have a nonlocal character. This necessitates a reexamination of its conventional physical interpretation. The magnetic energy is also discussed. RP MARSH, GE (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 32 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1993 VL 47 IS 5 BP 3607 EP 3611 DI 10.1103/PhysRevE.47.3607 PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA LF067 UT WOS:A1993LF06700070 ER PT J AU NING, L ECKE, RE AF NING, L ECKE, RE TI KUPPERS-LORTZ TRANSITION AT HIGH DIMENSIONLESS ROTATION RATES IN ROTATING RAYLEIGH-BENARD CONVECTION SO PHYSICAL REVIEW E LA English DT Note ID LAYER AB We show that for rotating Rayleigh-Benard convection over a range of dimensionless rotation rates 270 < OMEGA < 2500, bulk convection structures are Kuppers-Lortz unstable near onset. We used optical shadow-graph imaging to visualize the pattern dynamics, found switching angles of approximately 60-degrees, and observed separate spatial domains where switchings took place at different times. The characteristic switching frequencies were found to depend weakly on the rotation rate. Finite-size and boundary effects were observed to complicate the switching dynamics close to onset. C1 LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP NING, L (reprint author), LOS ALAMOS NATL LAB,DIV PHYS,LOS ALAMOS,NM 87545, USA. NR 14 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 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1993 VL 47 IS 5 BP R2991 EP R2994 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA LF067 UT WOS:A1993LF06700005 ER PT J AU STAMATELATOS, IE DILMANIAN, FA MA, R LIDOFSKY, LJ WEBER, DA PIERSON, RN KAMEN, Y YASUMURA, S AF STAMATELATOS, IE DILMANIAN, FA MA, R LIDOFSKY, LJ WEBER, DA PIERSON, RN KAMEN, Y YASUMURA, S TI CALIBRATION FOR MEASURING TOTAL-BODY NITROGEN WITH A NEWLY UPGRADED PROMPT GAMMA-NEUTRON ACTIVATION FACILITY SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID INVIVO DETERMINATION; INSTRUMENT; HYDROGEN; DISEASE; PROTEIN; CAPTURE AB A description is given of the calibration and performance of the upgraded facility at Brookhaven National Laboratory (BNL) for measuring total body nitrogen using the technique of prompt gamma neutron activation analysis. With the improved calibration, total body nitrogen can be more accurately measured not only in normal subjects but also in obese and wasted patients. Body hydrogen is used as an internal standard. We examined the effect of a heavy-water premoderator on the uniformity of composite sensitivity, nitrogen and hydrogen measurement statistics, and dose to the subject. The calibration technique corrects the ratio of nitrogen-to-hydrogen counts measured from the subject for body size. Additionally, a correction for subcutaneous adipose tissue on the nitrogen-to-hydrogen count ratio is introduced. The newly upgraded BNL facility provides precision in counting statistics using a Remcal anthropomorphic phantom filled with a tissue-equivalent solution of 2.1% for a body dose of 0.35 mSv using a 2.5 cm D2O premoderator. The measurements were made at five 20 cm sections, counting for 200 s per section. C1 ST SAVAS HOSP,DEPT MED PHYS,GR-11522 ATHENS,GREECE. COLUMBIA UNIV,DEPT APPL PHYS,NEW YORK,NY 10027. SUNY HLTH SCI CTR,BROOKLYN,NY 11203. COLUMBIA UNIV,ST LUKES ROOSEVELT MED CTR,NEW YORK,NY 10027. RP STAMATELATOS, IE (reprint author), BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973, USA. FU NIDDK NIH HHS [P01-DK42618] NR 28 TC 30 Z9 30 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD MAY PY 1993 VL 38 IS 5 BP 615 EP 626 DI 10.1088/0031-9155/38/5/004 PG 12 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA LG172 UT WOS:A1993LG17200004 PM 8321889 ER PT J AU LUND, SM DAVIDSON, RC AF LUND, SM DAVIDSON, RC TI A CLASS OF COHERENT VORTEX STRUCTURES IN ROTATING NONNEUTRAL PLASMA SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID NONLINEAR DIOCOTRON MODE; PURE ELECTRON PLASMAS; STABILITY THEOREM; FLOW AB A class of nonaxisymmetric (partial derivative/partial derivative theta not-equal 0) rotating equilibria is investigated theoretically for strongly magnetized, low-density (omega(pe)2/omega(ce)2 much less than 1) pure electron plasma confined radially by a uniform axial magnetic field B0e(z) between concentric, perfectly conducting, cylindrical walls located at radii r = r(w) and r = r(I) < r(w). The analysis is based on a nonrelativistic, guiding-center model in the cold-fluid limit that treats the electrons as a massless fluid (m(e) --> 0) with E X B flow velocity V(e) = -(c/B0)delphi X e(z). Assuming two-dimensional spatial variations (partial derivative/partial derivative z = 0), the continuity-Poisson equations are analyzed for rotating coherent structures that are stationary (time independent) in a frame of reference rotating with angular velocity omega(r) = const about the cylinder axis (r = 0). The equilibrium Poisson equation del2psi = -4pie2n(e)(psi) + 2omega(r)eB0/c is solved exactly for the particular case where the electron density n(e)(psi) is a linear function of the streamfunction psi = -ephi + omega(r)(eB0/2c)r2, and the plasma fills the region between the conducting walls, with n(e) = 0 at r = r(I) and r = r(w). It is found that this class of rotating equilibria can exhibit large-amplitude, nonaxisymmetric, vortex structures characterized by strong azimuthal density bunching and circulating electron flow within the density bunches. Nonlinear stability properties are investigated using the Lyapunov method, and the vortex equilibria with azimuthal mode number l = 1 are shown to be stable. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP LUND, SM (reprint author), PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 30 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD MAY PY 1993 VL 5 IS 5 BP 1421 EP 1429 DI 10.1063/1.860882 PG 9 WC Physics, Fluids & Plasmas SC Physics GA LB721 UT WOS:A1993LB72100008 ER PT J AU TRACY, MD WILLIAMS, EA ESTABROOK, KG DEGROOT, JS CAMERON, SM AF TRACY, MD WILLIAMS, EA ESTABROOK, KG DEGROOT, JS CAMERON, SM TI EIGENVALUE SOLUTION FOR THE ION-COLLISIONAL EFFECTS ON ION-ACOUSTIC AND ENTROPY WAVES SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID ELECTROMAGNETIC-WAVES; LIGHT-SCATTERING; LASER FUSION; PLASMAS; TURBULENCE AB The linearized ion Fokker-Planck equation is solved as an eigenvalue problem under the condition of collisionless electrons in the quasineutral limit (phi = 0) for ionization-temperature ratios, ZT(e)/T(i) = 2, 4, and 8 for entropy waves and ionization-temperature ratios, ZT(e)/T(i) = 4, 8, 16, 32, 48, 64, and 80 for ion-acoustic waves. The perturbed ion distribution function for the ion-acoustic and entropy waves is formed from a Legendre polynomial expansion of eigenvectors and can be used to calculate collisionally dependent macroscopic quantities in the plasma such as gamma (GAMMA = C(p)/C(upsilon)), the ratio of specific heats, and the ion thermal conductivity (kappa(i)). C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. UNIV CALIF DAVIS,PLASMA RES GRP,DAVIS,CA 95616. RP TRACY, MD (reprint author), UNIV CALIF DAVIS,DEPT APPL SCI,DAVIS,CA 95616, USA. NR 24 TC 31 Z9 32 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD MAY PY 1993 VL 5 IS 5 BP 1430 EP 1439 DI 10.1063/1.860883 PG 10 WC Physics, Fluids & Plasmas SC Physics GA LB721 UT WOS:A1993LB72100009 ER PT J AU MYNICK, HE AF MYNICK, HE TI TRANSPORT OF ENERGETIC IONS BY LOW-N MAGNETIC PERTURBATIONS SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID CYCLOTRON RANGE; TOKAMAK; CONFINEMENT; PLASMA; WAVES; TFTR AB The stochastic transport of MeV ions induced by low-n magnetic perturbations is studied, focusing chiefly on the stochastic mechanism operative for passing particles in low-frequency perturbations. Beginning with a single-harmonic form for the perturbing field, it is first shown numerically and analytically that the stochastic threshold of energetic particles can be substantially lower than that of the magnetic field, contrary to earlier expectations, so that magnetic perturbations could cause appreciable loss of energetic ions without destroying the bulk confinement. The analytic theory is then extended in a number of directions, to clarify the relation of the present stochastic mechanism to instances already found, to allow for more complex perturbations, and to consider the more general relationship between the stochasticity of magnetic fields and that of particles of differing energies (and pitch angles) moving in those fields. It is shown that the stochastic threshold is, in general, a nonmonotonic function of energy, whose form can to some extent be tailored to achieve desired goals (e.g., burn control or ash removal) by a judicious choice of the perturbation. Illustrative perturbations are exhibited that are stochastic for low- but not for high-energy ions, for high- but not for low-energy ions, and for intermediate-energy ions, but not for low or high energy. The second possibility is the behavior needed for burn control; the third provides a possible mechanism for ash removal. RP MYNICK, HE (reprint author), PRINCETON UNIV,PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 34 TC 53 Z9 54 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD MAY PY 1993 VL 5 IS 5 BP 1471 EP 1481 DI 10.1063/1.860886 PG 11 WC Physics, Fluids & Plasmas SC Physics GA LB721 UT WOS:A1993LB72100012 ER PT J AU CARRERAS, BA LYNCH, VE GARCIA, L DIAMOND, PH AF CARRERAS, BA LYNCH, VE GARCIA, L DIAMOND, PH TI RESISTIVE PRESSURE-GRADIENT-DRIVEN TURBULENCE WITH SELF-CONSISTENT FLOW PROFILE EVOLUTION SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID RADIAL ELECTRIC-FIELD; EDGE TURBULENCE; POLOIDAL ROTATION; TOKAMAK EDGE; GENERATION AB Resistive pressure-gradient-driven turbulence causes a modification of the average poloidal flow profile through Reynolds stress. The poloidal flow profile modification can be induced through a diamagnetic term and/or ''seed'' flow. This leads to several possible results for the steady-state poloidal flow profile. If this profile is such that V(theta)'' not-equal 0 at the singular surface, there is a reduction in linear growth rate and suppression of the fluctuation. When V(theta)'' = 0 and V(theta)' not-equal 0, there is linear stabilization but the fluctuation suppression is weak. C1 EURATOM,ASSOC CIEMAT,MADRID,SPAIN. UNIV COMPLUTENSE MADRID,MADRID 3,SPAIN. UNIV CALIF SAN DIEGO,LA JOLLA,CA 92093. RP CARRERAS, BA (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. RI Lynch, Vickie/J-4647-2012; Garcia, Luis/A-5344-2015 OI Lynch, Vickie/0000-0002-5836-7636; Garcia, Luis/0000-0002-0492-7466 NR 23 TC 59 Z9 59 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD MAY PY 1993 VL 5 IS 5 BP 1491 EP 1505 DI 10.1063/1.860889 PG 15 WC Physics, Fluids & Plasmas SC Physics GA LB721 UT WOS:A1993LB72100015 ER PT J AU BOIVIN, RL ZWEBEN, SJ AF BOIVIN, RL ZWEBEN, SJ TI MIDPLANE MEASUREMENTS OF CHARGED FUSION PRODUCT DIFFUSION IN THE TOKAMAK FUSION TEST REACTOR SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID CONFINEMENT; PROBES; PLASMA; TFTR; EDGE AB A radially movable detector located just below the outer midplane of the Tokamak Fusion Test Reactor (TFTR) [in Plasma Physics and Controlled Nuclear Fusion Research, 1988 (International Atomic Energy Agency, Vienna, 1989), Vol. 1, p. 27] has been used to study the confinement of charged fusion products (CFP's). The scrape-off length of escaping CFP flux was measured using perturbative techniques based on shadowing the detector with different obstacles. Experimental results indicate the presence of a diffusive process for trapped particles. Derived diffusion step sizes were found to be in excellent agreement with those expected from toroidal magnetic field (TF) stochastic ripple diffusion. C1 PRINCETON UNIV,PLASMA PHYS LAB,PRINCETON,NJ 08543. RP BOIVIN, RL (reprint author), MIT,CTR PLASMA FUS,175 ALBANY ST,CAMBRIDGE,MA 02139, USA. NR 15 TC 15 Z9 15 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD MAY PY 1993 VL 5 IS 5 BP 1559 EP 1566 DI 10.1063/1.860895 PG 8 WC Physics, Fluids & Plasmas SC Physics GA LB721 UT WOS:A1993LB72100021 ER PT J AU WOOSLEY, S BARNES, C CLAYTON, D FULLER, G MATHEWS, G SCHRAMM, D AF WOOSLEY, S BARNES, C CLAYTON, D FULLER, G MATHEWS, G SCHRAMM, D TI NUCLEAR ASTROPHYSICS - PROCEEDINGS OF THE CALTECH CENTENNIAL YEAR NUCLEAR ASTROPHYSICS SYMPOSIUM IN HONOR OF FOWLER,WILLIAM,A. 80TH BIRTHDAY - PREFACE SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Editorial Material C1 UNIV CHICAGO,CTR ASTRON & ASTROPHYS,CHICAGO,IL 60637. UNIV CALIF SANTA CRUZ,UCO UCK OBSERV,BOARD STUDIES ASTRON & ASTROPHYS,SANTA CRUZ,CA 95064. UNIV CALIF SAN DIEGO,DEPT PHYS,LA JOLLA,CA 92093. CLEMSON UNIV,DEPT PHYS & ASTRON,CLEMSON,SC 29631. RP WOOSLEY, S (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT PHYS,GEN STUDIES GRP,LIVERMORE,CA 94550, USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD MAY PY 1993 VL 227 IS 1-5 BP 3 EP 3 DI 10.1016/0370-1573(93)90051-E PG 1 WC Physics, Multidisciplinary SC Physics GA LH206 UT WOS:A1993LH20600001 ER PT J AU KOLB, EW AF KOLB, EW TI THE INFLATIONARY DECADE SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID EXTENDED INFLATION; PHASE-TRANSITION; DENSITY PERTURBATIONS; SYMMETRY-BREAKING; INDUCED-GRAVITY; FALSE VACUUM; UNIVERSE; COSMOLOGY; GENERATION; FATE AB In the ten years since Guth proposed the inflationary Universe, we have come to appreciate the rich and varied phenomena associated with inflation; most of them unanticipated in the original work. We have also learned that inflation is a picture than can be accommodated within many frameworks. In this paper I review some of the models for inflation (old, new, chaotic, extended, etc.). I also discuss some of the ''generic'' predictions of inflation, particularly those that bear upon nuclear astrophysics. C1 UNIV CHICAGO,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637. UNIV CHICAGO,ENRICO FERMI INST,CHICAGO,IL 60637. RP KOLB, EW (reprint author), FERMILAB NATL ACCELERATOR LAB,NASA FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510, USA. NR 38 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD MAY PY 1993 VL 227 IS 1-5 BP 5 EP 12 DI 10.1016/0370-1573(93)90052-F PG 8 WC Physics, Multidisciplinary SC Physics GA LH206 UT WOS:A1993LH20600002 ER PT J AU WEAVER, TA WOOSLEY, SE AF WEAVER, TA WOOSLEY, SE TI NUCLEOSYNTHESIS IN MASSIVE STARS AND THE C-12(ALPHA,GAMMA)O-16 REACTION-RATE SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID WEAK-INTERACTION RATES; STELLAR CORE COLLAPSE; CROSS-SECTION; EXPLOSIVE NUCLEOSYNTHESIS; ENERGIES; SUPERNOVA; EVOLUTION; NUCLEI; SILICON; OXYGEN AB The evolution of a grid of massive stars ranging from 12 to 40 M. has been followed through all stages of nuclear burning up to the point of iron core collapse. The critical and highly uncertain rate for the reaction C-12(alpha, gamma) O-16 has been varied over a range from 0.5 to 3.0 times that given by Caughlan and Fowler and two different prescriptions for semiconvection have been explored. The nucleosynthesis resulting from integrating the yields of these models over plausible initial stellar mass distributions is found to be in excellent agreement with the observed solar abundances of virtually all the intermediate mass isotopes (16 less-than-or-equal-to A less-than-or-equal-to 32) if, and only if, the rate of the C-12(alpha, gamma)O-16 reaction is taken to be 1.7+/-0.5 times that given by Caughlan and Fowler. This range is a small subset of what is allowed by current experimental measurements and can be taken as a nucleosynthetic ''prediction'' of the value that this rate needs to have in order to prevent 5- to 100-fold deviations from the observed relative abundances of key isotopes. These results are insensitive to the assumed slope of the initial stellar mass distribution within observational limits, and relatively insensitive to the theory of semiconvection (except for the apparent excessive production of O-18 when semiconvective mixing is suppressed). Three of the stars have been followed through simulated explosions to obtain the explosive modifications to their nucleosynthesis (including the ''neutrino process''), which for most isotopes is relatively small. Isotopic yields of both stable and radioactive products are tabulated as are the calculated iron core masses of the presupernova stars. C1 UNIV CALIF SANTA CRUZ,UCO LICK OBSERV,BOARD STUDIES ASTRON & ASTROPHYS,SANTA CRUZ,CA 95064. RP WEAVER, TA (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT PHYS,GEN STUDIES GRP,LIVERMORE,CA 94550, USA. NR 66 TC 321 Z9 324 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD MAY PY 1993 VL 227 IS 1-5 BP 65 EP 96 DI 10.1016/0370-1573(93)90058-L PG 32 WC Physics, Multidisciplinary SC Physics GA LH206 UT WOS:A1993LH20600008 ER PT J AU WILSON, JR MAYLE, RW AF WILSON, JR MAYLE, RW TI REPORT ON THE PROGRESS OF SUPERNOVA RESEARCH BY THE LIVERMORE GROUP SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID ANNIHILATION AB We report on the current state of our research in the understanding of the evolution of core collapse supernovae. Convection in the post collapse stellar core (proto neutron star) is an important ingredient to the success of the neutrino heating mechanism; we discuss our model and indicate the sensitivity of our calculations to the inclusion of this convective model. RP WILSON, JR (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 14 TC 146 Z9 147 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD MAY PY 1993 VL 227 IS 1-5 BP 97 EP 111 DI 10.1016/0370-1573(93)90059-M PG 15 WC Physics, Multidisciplinary SC Physics GA LH206 UT WOS:A1993LH20600009 ER PT J AU COLGATE, SA HERANT, M BENZ, W AF COLGATE, SA HERANT, M BENZ, W TI NEUTRON-STAR ACCRETION AND THE NEUTRINO FIREBALL SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID SUPERNOVA 1987A; LINE-PROFILES; LATE BEHAVIOR; LIGHT-CURVE; X-RAY; SN-1987A; INSTABILITIES; CONVECTION; COLLAPSE; EMISSION AB We suggest a mechanism for driving supernova explosions through neutrino energy deposition beyond the formation and the cooling of the neutron star. The mechanism depends upon convection next to the neutron star and terminates when the entropy of buoyant bubbles increases sufficiently due to neutrino heating to shut off the down flow of low entropy matter. This convection is initially caused by the heat deposited from neutrinos emitted by the cooling neutron star in a region gravitationally dominated by the neutron star. This convection by providing an efficient heat transport mechanism avoids the overheating and excessive neutrino energy losses in the regions close to the neutron stars and has been recently modeled by Herant, Benz and Colgate. In this model the explosion shock, initially driven by the bounce followed by neutron star derived neutrino heating is further driven by the up flow of the buoyant, high entropy bubbles. The down flow between the bubbles of low entropy matter originating from behind the bounce and later the explosion shock will build up a modest entropy atmosphere in pressure equilibrium with the surface of the cooling neutron star. For modest entropies, S(rad) almost-equal-to 10 or S(total) almost-equal-to 18, and condensed neutron stars, R/M almost-equal-to 10 km per solar mass, the total mass of such an atmosphere is small, 1.7 x 10(-3) M., but the temperature at the base of such an atmosphere is extremely high, T almost-equal-to 10 MeV. The paradoxical result of neutrino emission is to further condense the atmosphere and increase the temperature until the compression heating is exceeded by the neutrino emission. The absolute limit of compression heating is free fall collapse, which may be approached but not exceeded. Such an accretion event approaching this limit may reach a temperature high enough to create a neutrino ''fireball'', a region hot enough, almost-equal-to 11 MeV, so as to be partially opaque to its own (neutrino) radiation. The further heating of the already high entropy bubbles by the neutrino deposition resulting from less extreme, but a continuing high temperature atmosphere, will augment the explosion shock. This convection-driven accretion should continue until the low entropy matter flowing downwords onto the neutron star is mixed to a high enough entropy by entrainment with the rising high entropy bubbles to prevent further accretion. This process, by providing for a feedback mechanism, may result in a robust supernova explosion in the sense that prior processes resulting in a failed or weak explosion will be augmented with further accretion energy until an explosion of the appropriate energy occurs. C1 CTR ASTROPHYS,CAMBRIDGE,MA 02138. UNIV ARIZONA,STEWARD OBSERV,TUCSON,AZ 85721. RP COLGATE, SA (reprint author), LOS ALAMOS NATL LAB,MS B275,LOS ALAMOS,NM 87544, USA. NR 41 TC 36 Z9 36 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD MAY PY 1993 VL 227 IS 1-5 BP 157 EP 174 DI 10.1016/0370-1573(93)90064-K PG 18 WC Physics, Multidisciplinary SC Physics GA LH206 UT WOS:A1993LH20600014 ER PT J AU MATHEWS, GJ BAZAN, G COWAN, JJ SCHRAMM, DN AF MATHEWS, GJ BAZAN, G COWAN, JJ SCHRAMM, DN TI HEAVY-ELEMENT NUCLEOSYNTHESIS AND GALACTIC CHEMICAL EVOLUTION SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID R-PROCESS NUCLEOSYNTHESIS; INTERMEDIATE-MASS STARS; COLD DARK MATTER; NEUTRON-CAPTURE NUCLEOSYNTHESIS; S-PROCESS NUCLEOSYNTHESIS; AGE-METALLICITY RELATION; GLOBULAR-CLUSTER SYSTEM; GIANT BRANCH EVOLUTION; METAL-POOR STARS; SOLAR NEIGHBORHOOD AB Two aspects of the relation between heavy-element nucleosynthesis and galactic chemical evolution are examined. In the first part, observed heavy-element abundance ratios in the halo and the disk are compared with one-zone models of galactic chemical evolution. These comparisons provide useful insight into the kinds of stellar environments responsible for r- and s-process nucleosynthesis. In the second part, we construct a schematic model for the formation and evolution of the Galaxy based upon the multiple mergers of protogalactic clouds within the expanding and collapsing halo. We analyze the various cosmochronometers within this model and show that the apparent differences between the maximum globular-cluster ages, the white-dwarf cooling age, and the nuclear chronometric ages can be interpreted as indicators of different aspects of the Galaxy formation process. C1 UNIV TEXAS, MCDONALD OBSERV, AUSTIN, TX 78712 USA. UNIV OKLAHOMA, DEPT PHYS & ASTRON, NORMAN, OK 73019 USA. FERMILAB NATL ACCELERATOR LAB, NASA FERMILAB ASTROPHYS GRP, BATAVIA, IL 60510 USA. UNIV CHICAGO, CHICAGO, IL 60637 USA. RP LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RI Bazan, Guillermo/B-7625-2014 NR 168 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 EI 1873-6270 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD MAY PY 1993 VL 227 IS 1-5 BP 175 EP 203 DI 10.1016/0370-1573(93)90065-L PG 29 WC Physics, Multidisciplinary SC Physics GA LH206 UT WOS:A1993LH20600015 ER PT J AU STARRFIELD, S TRURAN, JW POLITANO, M SPARKS, WM NOFAR, I SHAVIV, G AF STARRFIELD, S TRURAN, JW POLITANO, M SPARKS, WM NOFAR, I SHAVIV, G TI NA-22 AND AL-26 PRODUCTION IN NOVA OUTBURSTS SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID HEAVY ELEMENT ABUNDANCES; CLASSICAL NOVAE; INTERSTELLAR-MEDIUM; CNO ABUNDANCES; MODELS; NUCLEOSYNTHESIS; VULPECULAE; EXPLOSIONS; SYSTEMS; HEAO-3 AB The consequences of accretion of hydrogen rich material onto ONeMg white dwarfs with masses of 1.0, 1.25, and 1.35 M. are examined. Our results demonstrate that novae produce both Na-22 and Al-26 in astrophysically interesting amounts. Hot hydrogen burning on ONeMg white dwarfs can produce as much as 2% of the ejected material as Al-26 and 3% as Na-22. The largest amount of Na-22 is produced by the highest mass ONeMg white dwarf nova systems which are predicted to be the fastest and most luminous of all types of nova. The largest amount of Al-26 is produced in the lowest mass white dwarfs, which according to our evolutionary calculations, should eject the largest amount of material. In support of this prediction, the observations of QU Vul, a slow ONeMg nova, indicate that it has ejected about 10(-3) M.. However, such a large amount of ejected mass is inconsistent with a typical ONeMg white dwarf mass > 1.25 M.. C1 UNIV CHICAGO,DEPT ASTRON,CHICAGO,IL 60637. UNIV CHICAGO,ENRICO FERMI INST,CHICAGO,IL 60637. LOS ALAMOS NATL LAB,DIV APPL THEORET PHYS,LOS ALAMOS,NM 87545. TECHNION ISRAEL INST TECHNOL,DEPT PHYS,IL-32000 HAIFA,ISRAEL. TECHNION ISRAEL INST TECHNOL,ASHER SPACE INST,IL-32000 HAIFA,ISRAEL. RP STARRFIELD, S (reprint author), ARIZONA STATE UNIV,DEPT PHYS & ASTRON,TEMPE,AZ 85287, USA. NR 53 TC 35 Z9 35 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD MAY PY 1993 VL 227 IS 1-5 BP 223 EP 234 DI 10.1016/0370-1573(93)90067-N PG 12 WC Physics, Multidisciplinary SC Physics GA LH206 UT WOS:A1993LH20600017 ER PT J AU TAYLOR, CB BARIOLA, PA GREEN, PJ AF TAYLOR, CB BARIOLA, PA GREEN, PJ TI RNS2 - A SENESCENCE-ASSOCIATED RNASE OF ARABIDOPSIS THAT DIVERGED FROM THE S-RNASES BEFORE SPECIATION SO PLANT PHYSIOLOGY LA English DT Meeting Abstract C1 MICHIGAN STATE UNIV,MSU DOE,PLANT RES LAB,E LANSING,MI 48824. MICHIGAN STATE UNIV,DEPT BIOCHEM,E LANSING,MI 48824. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD MAY PY 1993 VL 102 IS 1 SU S BP 11 EP 11 PG 1 WC Plant Sciences SC Plant Sciences GA LD890 UT WOS:A1993LD89000049 ER PT J AU REYNOLDS, T BEDNAREK, S SCHROEDER, M RAIKHEL, N AF REYNOLDS, T BEDNAREK, S SCHROEDER, M RAIKHEL, N TI THE ARAB6 GENE IN ARABIDOPSIS-THALIANA ENCODES A SMALL GTP-BINDING PROTEIN SO PLANT PHYSIOLOGY LA English DT Meeting Abstract C1 MSU,DOE,PLANT RES LAB,E LANSING,MI 48824. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD MAY PY 1993 VL 102 IS 1 SU S BP 18 EP 18 PG 1 WC Plant Sciences SC Plant Sciences GA LD890 UT WOS:A1993LD89000085 ER PT J AU DONG, L STEVENS, F SCHIFFER, M ANDERSON, LE AF DONG, L STEVENS, F SCHIFFER, M ANDERSON, LE TI CYSTEINE CLUSTERS IN THE LIGHT-ACTIVATED CHLOROPLAST ENZYMES SO PLANT PHYSIOLOGY LA English DT Meeting Abstract C1 UNIV ILLINOIS,CHICAGO,IL 60607. ARGONNE NATL LAB,DIV BIOL & MED,ARGONNE,IL 60439. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD MAY PY 1993 VL 102 IS 1 SU S BP 37 EP 37 PG 1 WC Plant Sciences SC Plant Sciences GA LD890 UT WOS:A1993LD89000192 ER PT J AU PUSHNIK, JC ANDERSON, PD FLORY, WB DEMAREE, RS HOUPIS, JLJ AF PUSHNIK, JC ANDERSON, PD FLORY, WB DEMAREE, RS HOUPIS, JLJ TI SINK-SOURCE CHARACTERISTICS OF 2 DISTINCTLY DIFFERENT FOREST SPECIES AS AFFECTED BY ELEVATED CARBON-DIOXIDE SO PLANT PHYSIOLOGY LA English DT Meeting Abstract C1 CALIF STATE UNIV CHICO,DEPT BIOL SCI,CHICO,CA 95929. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD MAY PY 1993 VL 102 IS 1 SU S BP 41 EP 41 PG 1 WC Plant Sciences SC Plant Sciences GA LD890 UT WOS:A1993LD89000205 ER PT J AU TAYLOR, CB GREEN, PJ AF TAYLOR, CB GREEN, PJ TI IDENTIFICATION AND CHARACTERIZATION OF GENES WITH UNSTABLE TRANSCRIPTS (GUTS) IN TOBACCO SO PLANT PHYSIOLOGY LA English DT Meeting Abstract C1 MICHIGAN STATE UNIV,DOE,PLANT RES LAB,E LANSING,MI 48823. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD MAY PY 1993 VL 102 IS 1 SU S BP 67 EP 67 PG 1 WC Plant Sciences SC Plant Sciences GA LD890 UT WOS:A1993LD89000362 ER PT J AU SCHNEIDER, C ROESSLER, P AF SCHNEIDER, C ROESSLER, P TI LIPID-METABOLISM IN AN OLEAGINOUS MARINE ALGA, NANNOCHLOROPSIS SO PLANT PHYSIOLOGY LA English DT Meeting Abstract C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. NR 0 TC 0 Z9 0 U1 2 U2 2 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD MAY PY 1993 VL 102 IS 1 SU S BP 93 EP 93 PG 1 WC Plant Sciences SC Plant Sciences GA LD890 UT WOS:A1993LD89000516 ER EF