FN Thomson Reuters Web of Science™ VR 1.0 PT J AU CHIN, YH KIM, KJ XIE, M AF CHIN, YH KIM, KJ XIE, M TI 3-DIMENSIONAL THEORY OF THE SMALL-SIGNAL HIGH-GAIN FREE-ELECTRON LASER INCLUDING BETATRON OSCILLATIONS SO PHYSICAL REVIEW A LA English DT Article ID UNIVERSAL SCALING FUNCTION; SPONTANEOUS EMISSION; REGIME AB We have developed a three-dimensional free-electron laser (FEL) theory in the small-signal high-gain regime based upon the Maxwell-Vlasov equations including the effects of the energy spread, the emittance, and the betatron oscillations of the electron beam. The radiation field is expressed in terms of the Green's function of the inhomogeneous wave equation and the distribution function of the electron beam. The distribution function is expanded in terms of a set of orthogonal functions determined by the unperturbed electron distributions. The coupled Maxwell-Vlasov equations are then reduced to a matrix equation, from which a dispersion relation for the eigenvalues is derived. The growth rate for the fundamental mode can be obtained for any initial beam distribution including the hollow-beam, the water-bag, and the Gaussian distribution. Comparisons of our numerical solutions with simulation results and with other analytical approaches show good agreements except for the one-dimensional limit. We present a handy interpolating formula for the FEL gain of a Gaussian beam, as a function of the scaled parameters, that can be used for a quick estimate of the gain. The present theory can be applied to the beam-conditioning case by a few modifications. RP CHIN, YH (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 14 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 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD NOV 15 PY 1992 VL 46 IS 10 BP 6662 EP 6683 DI 10.1103/PhysRevA.46.6662 PG 22 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA JZ678 UT WOS:A1992JZ67800066 ER PT J AU WHITTUM, DH LAMPE, M JOYCE, G SLINKER, SP YU, SS SHARP, WM AF WHITTUM, DH LAMPE, M JOYCE, G SLINKER, SP YU, SS SHARP, WM TI FLUTE INSTABILITY OF AN ION-FOCUSED SLAB ELECTRON-BEAM IN A BROAD PLASMA SO PHYSICAL REVIEW A LA English DT Article ID LASER-IONIZED CHANNEL; HOSE INSTABILITY; TRANSVERSE OSCILLATIONS; REGIME; PROPAGATION; ACCELERATOR; TRANSPORT AB An intense relativistic electron beam with an elongated cross section, propagating in the ion-focused regime through a broad, uniform, unmagnetized plasma, is shown to suffer a transverse flute instability. This instability arises from the electrostatic coupling between the beam and the plasma electrons at the ion-channel edge. The instability is found to be absolute and the asymptotic growth of the flute amplitude is computed in the "frozen-field" approximation and the large skin-depth limit. The minimum growth length is shown to be much less than the betatron period, with the consequence that focusing is rendered ineffective. It is further shown that growth is much reduced when the beam propagates through a narrow channel where the ion density greatly exceeds that of the surrounding plasma. In this limit, a modest spread in betatron frequency produces rapid saturation. The effect of plasma electron collisions is also considered. Results of beam breakup simulations are noted. C1 USN,RES LAB,WASHINGTON,DC 20375. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP WHITTUM, DH (reprint author), NATL LAB HIGH ENERGY PHYS,1-1 OHO,OHO,IBARAKI 305,JAPAN. NR 47 TC 12 Z9 12 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD NOV 15 PY 1992 VL 46 IS 10 BP 6684 EP 6699 DI 10.1103/PhysRevA.46.6684 PG 16 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA JZ678 UT WOS:A1992JZ67800067 ER PT J AU BAK, P FLYVBJERG, H LAUTRUP, B AF BAK, P FLYVBJERG, H LAUTRUP, B TI COEVOLUTION IN A RUGGED FITNESS LANDSCAPE SO PHYSICAL REVIEW A LA English DT Article AB A variant of Kauffman's NKC model for the coevolution of haploid organisms is shown to have two phases: a frozen phase in which all species eventually reach local fitness maxima and stop evolving, and a chaotic phase in which a fraction of all species is at local maxima, while another fraction evolves towards maxima. In doing so, they set other species back in evolution, thereby maintaining a steady fraction of evolving species. The evolutionary activity of the steady state is a natural order parameter for the ecosystem. Closed expressions are given for this order parameter and for the system's relaxation time. The latter quantity diverges at the phase boundary, showing the system is critical there. All results were obtained analytically for the maximally rugged case of K + 1 = N, and to leading order in N, the number of genes in a species. C1 NIELS BOHR INST,CTR COMPUTAT NEURAL NETWORK,DK-2100 COPENHAGEN 0,DENMARK. RP BAK, P (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. RI Flyvbjerg, Henrik/C-1127-2009 OI Flyvbjerg, Henrik/0000-0002-1691-9367 NR 12 TC 29 Z9 29 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 NOV 15 PY 1992 VL 46 IS 10 BP 6724 EP 6730 DI 10.1103/PhysRevA.46.6724 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA JZ678 UT WOS:A1992JZ67800071 ER PT J AU YELON, A MOVAGHAR, B BRANZ, HM AF YELON, A MOVAGHAR, B BRANZ, HM TI ORIGIN AND CONSEQUENCES OF THE COMPENSATION (MEYER-NELDEL) LAW SO PHYSICAL REVIEW B LA English DT Article ID RULE; SILICON; CONDUCTIVITY; TRANSPORT; CRYSTALS; HYDROGEN; ENTROPY AB We have recently demonstrated that the Meyer-Neldel (MN) rule (compensation law) may be understood as arising naturally when the activation energy for a process is significantly larger than both the typical excitations available and kT. This conclusion was supported by the results of two microscopic models, related to special cases. In the present paper we present arguments, based on general results from statistical physics, which lead to the same conclusion. We show that this simple explanation also leads to the solution of a number of puzzles which have been associated with Meyer-Neldel behavior. We show that phenomena in groups of similar materials yield similar MN slopes. Finally, we show that the values of the slope for semiconductors with gaps in the 1-2-eV range are consistent with the suggestion that optical phonons are the source of the excitation energy in such processes. C1 ECOLE POLYTECH,DEPT GENIE PHYS,MONTREAL H3C 3A7,QUEBEC,CANADA. UNIV MARBURG,FACHBEREICH PHYS,W-3550 MARBURG,GERMANY. NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. RP YELON, A (reprint author), ECOLE POLYTECH,COUCHES MINCES GRP,MONTREAL H3C 3A7,QUEBEC,CANADA. NR 39 TC 181 Z9 182 U1 2 U2 16 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 NOV 15 PY 1992 VL 46 IS 19 BP 12244 EP 12250 DI 10.1103/PhysRevB.46.12244 PG 7 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900015 ER PT J AU LEON, RP KAMINSKA, M YU, KM WEBER, ER AF LEON, RP KAMINSKA, M YU, KM WEBER, ER TI FORMATION OF SEMIINSULATING INP THROUGH METALLIC CU-RICH PRECIPITATES SO PHYSICAL REVIEW B LA English DT Article ID SCHOTTKY-BARRIER HEIGHTS; FE; SEMICONDUCTORS; SPECTROSCOPY; IMPURITIES; SURFACES; LAYERS AB A set of diffusion experiments of Cu in InP have shown that this semiconductor exhibits a transition to semi-insulating behavior after relatively low Cu diffusion temperatures. The study described here involves structural, ion-beam/channeling, magnetic, and electrical measurements. It was observed that most or all of the Cu precipitates form a Cu-In compound, that both originally n- and p-type InP become semi-insulating upon Cu diffusion, and that there is a negligible concentration of deep-level defects in Cu-doped InP. Further observations include an abnormal reduction in both electron and hole mobilities resulting from the introduction of Cu, and the occurrence of isolated pockets of conductive InP in otherwise semi-insulating material. The concurrence of these experimental observations can best be explained using the buried Schottky-barrier model instead of the commonly observed compensation by deep levels. C1 UNIV WARSAW,INST EXPTL PHYS,PL-00681 WARSAW,POLAND. LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP LEON, RP (reprint author), UNIV CALIF BERKELEY,DEPT MAT SCI,BERKELEY,CA 94720, USA. RI Yu, Kin Man/J-1399-2012 OI Yu, Kin Man/0000-0003-1350-9642 NR 28 TC 20 Z9 20 U1 0 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 NOV 15 PY 1992 VL 46 IS 19 BP 12460 EP 12468 DI 10.1103/PhysRevB.46.12460 PG 9 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900043 ER PT J AU NILES, DW RIOUX, D HOCHST, H AF NILES, DW RIOUX, D HOCHST, H TI POLARIZATION SELECTION-RULES IN PHOTOEMISSION FROM THE VALENCE BANDS OF ZINC-BLENDE-STRUCTURE SEMICONDUCTORS SO PHYSICAL REVIEW B LA English DT Article ID ANGLE-RESOLVED PHOTOEMISSION; SPECTROSCOPY; GAAS; DISPERSIONS; INSB; GAP AB Bulk valence-band transitions in angle-resolved photoemission spectra depend on the polarization of the incident light. The suppression or enhancement of direct transitions results from symmetry enforced selection rules in the photoexcitation process. Photoemission involves a transition from an initial valence band to a final-state band via the electric dipole perturbation describing the photon. This paper focuses on the symmetries of the initial states, the photon operators, and the final states. The final-state band symmetries are deduced from free-electron-like bands. Applying symmetry arguments to the photon matrix element, we infer important selection rules for different polarization geometries of the photon field. We apply the concept to normal emission valence-band spectra of the split-off band in CdTe(100), showing that the transition along the DELTA line is the dominant emission feature for p polarization while it is completely suppressed using s-polarized light. C1 SYNCHROTRON RADIAT CTR,STOUGHTON,WI 53589. RP NILES, DW (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 23 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 NOV 15 PY 1992 VL 46 IS 19 BP 12547 EP 12553 DI 10.1103/PhysRevB.46.12547 PG 7 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900053 ER PT J AU LAKS, DB FERREIRA, LG FROYEN, S ZUNGER, A AF LAKS, DB FERREIRA, LG FROYEN, S ZUNGER, A TI EFFICIENT CLUSTER-EXPANSION FOR SUBSTITUTIONAL SYSTEMS SO PHYSICAL REVIEW B LA English DT Article ID TRANSITION-METAL ALLOYS; DENSITY-FUNCTIONAL THEORY; ABSORPTION FINE-STRUCTURE; PHASE-STABILITY; SOLID-SOLUTIONS; TOTAL-ENERGY; 1ST-PRINCIPLES CALCULATION; ELECTRONIC THEORY; BINARY-ALLOYS; CU-AG AB We demonstrate a cluster expansion technique that is capable of accurately predicting formation energies in binary substitutional systems-even for those with large atomic relaxations. Conventional cluster expansions converge rapidly only in the absence of atomic relaxations, and they fail for long-period lattice-mismatched superlattices. When combined with first-principles total-energy methods, our method allows for very fast calculations for structures containing hundreds or thousands of atoms. The convergence and effectiveness of the cluster expansion are enhanced in two ways. First, the expansion is recast into reciprocal space, which allows for the inclusion of all important pair interactions. Second, a reciprocal-space formulation for elastic strain energy is introduced, allowing accurate predictions for both long- and short-period superlattices. We illustrate the power of the method by performing a cluster expansion that requires total-energy calculations for only 12 simple input structures, with at most eight atoms per unit cell. We then correctly predict the formation energies of relaxed long-period superlattices, low-symmetry intermixed superlattices, structures with varied compositions, substitutional impurities, and a approximately 1000 atom/cell simulation of the random alloy. RP LAKS, DB (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. RI Zunger, Alex/A-6733-2013 NR 52 TC 203 Z9 203 U1 2 U2 33 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 NOV 15 PY 1992 VL 46 IS 19 BP 12587 EP 12605 DI 10.1103/PhysRevB.46.12587 PG 19 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900058 ER PT J AU BARTELT, MC EVANS, JW AF BARTELT, MC EVANS, JW TI SCALING ANALYSIS OF DIFFUSION-MEDIATED ISLAND GROWTH IN SURFACE-ADSORPTION PROCESSES SO PHYSICAL REVIEW B LA English DT Article ID THIN-FILMS; SI; CHEMISORPTION; PERCOLATION; CLUSTERS; LATTICE AB We examine the competition between diffusion-mediated irreversible nucleation and growth of islands during submonolayer deposition on perfect substrates. We provide a detailed scaling theory for the complete distribution of island sizes and separations, both with the ratio of diffusion to deposition rate and with time. Scaling functions and exponents are obtained by simulation. The leading scaling behavior is independent of details of the island structure. These results are supplemented by an analysis of rate equations for the island-size distribution whose unconventional form appropriately describes island nucleation and growth mechanisms. The exponents agree with the simulations and the island-size distribution shows qualitative agreement. We further provide simulation results for the scaling of the island-separation distribution, quantifying, in particular, the depletion in the concentration of pairs of islands at small separations. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT MATH,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. RP BARTELT, MC (reprint author), IOWA STATE UNIV SCI & TECHNOL,INST PHYS RES & TECHNOL,AMES,IA 50011, USA. NR 23 TC 386 Z9 388 U1 3 U2 21 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 NOV 15 PY 1992 VL 46 IS 19 BP 12675 EP 12687 DI 10.1103/PhysRevB.46.12675 PG 13 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900066 ER PT J AU LEE, SJ KETTERSON, JB TRIVEDI, N AF LEE, SJ KETTERSON, JB TRIVEDI, N TI METAL-INSULATOR-TRANSITION IN QUASI-2-DIMENSIONAL MO-C FILMS SO PHYSICAL REVIEW B LA English DT Article ID ELECTRON-ELECTRON INTERACTION; COULOMB GAP; DISORDERED SYSTEMS; INVERSION-LAYERS; SCALING THEORY; 2 DIMENSIONS; SUPERCONDUCTIVITY; LOCALIZATION; MAGNETORESISTANCE; CONDUCTIVITY AB We have studied the insulator-to-metal transition in Mo-C films by tuning the thickness from 2.6 to 20 angstrom. The temperature dependence of the conductivity evolves from hopping transport, for the thin insulating films, to a InT dependence for the thicker metallic films. In the insulating regime we find a variable range Mott hopping law at high temperatures crossing over to Efros-Shklovskii hopping at lower temperatures with the opening of a soft Coulomb gap. We also obtain the dependence of the characteristic parameters on the film thickness. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. NORTHWESTERN UNIV,MAT RES CTR,EVANSTON,IL 60208. RP LEE, SJ (reprint author), NORTHWESTERN UNIV,DEPT PHYS & ASTRON,EVANSTON,IL 60208, USA. RI Ketterson, John/B-7234-2009 NR 31 TC 21 Z9 21 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 NOV 15 PY 1992 VL 46 IS 19 BP 12695 EP 12700 DI 10.1103/PhysRevB.46.12695 PG 6 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900068 ER PT J AU COFFEY, D TRUGMAN, SA AF COFFEY, D TRUGMAN, SA TI CORRELATIONS FOR THE S=1/2 ANTIFERROMAGNET ON A TRUNCATED TETRAHEDRON SO PHYSICAL REVIEW B LA English DT Article ID BOND AB The antiferromagnetic Heisenberg Hamiltonian is investigated on a truncated tetrahedron, which is a closed 12-site system. We find that the ground state has many similarities to that of C60. We study two- and four-spin correlations in the classical ground state of the truncated tetrahedron and calculate the same correlations in the exact S = 1/2 ground state. We find that the classical correlations survive for a range of bond strengths in the Heisenberg Hamiltonian and that one can construct a good trial wave function based on the classical ground state. This suggests that the correlations present in the classical ground state of C60 also survive in the exact ground state of that system, for a range of bond strengths about the physically relevant J2 almost-equal-to J1. We calculate the momentum-space correlation function S(q), which is measurable by neutron scattering, for both C-12 and C60. We also calculate correlations at finite temperature. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP COFFEY, D (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,MS-K765,LOS ALAMOS,NM 87545, USA. NR 7 TC 12 Z9 12 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 NOV 15 PY 1992 VL 46 IS 19 BP 12717 EP 12722 DI 10.1103/PhysRevB.46.12717 PG 6 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900070 ER PT J AU HOEN, S CHOPRA, NG XIANG, XD MOSTOVOY, R HOU, JG VAREKA, WA ZETTL, A AF HOEN, S CHOPRA, NG XIANG, XD MOSTOVOY, R HOU, JG VAREKA, WA ZETTL, A TI ELASTIC PROPERTIES OF A VANDERWAALS SOLID - C-60 SO PHYSICAL REVIEW B LA English DT Article ID STATE AB The elastic response (Young's modulus and internal friction) of solid C60 has been measured in single-crystal specimens as a function of temperature. We determine a Debye temperature of approximately 100 K and a room-temperature Young's modulus of 2.0+/-0.5X10(11) dyn/cm2. The elastic properties are strongly anharmonic and indicate phase transitions at approximately 150 and approximately 269 K. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP HOEN, S (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Hou, Jianguo/G-5076-2010; Xiang, Xiaodong/A-9445-2012; Zettl, Alex/O-4925-2016; Xiang, Xiaodong/A-5936-2017 OI Zettl, Alex/0000-0001-6330-136X; NR 15 TC 65 Z9 65 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 NOV 15 PY 1992 VL 46 IS 19 BP 12737 EP 12739 DI 10.1103/PhysRevB.46.12737 PG 3 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900073 ER PT J AU EBERHART, ME DONOVAN, MM OUTLAW, RA AF EBERHART, ME DONOVAN, MM OUTLAW, RA TI ABINITIO CALCULATIONS OF OXYGEN DIFFUSIVITY IN GROUP-IB TRANSITION-METALS SO PHYSICAL REVIEW B LA English DT Note AB First-principles investigations of oxygen transport through Cu, Ag, and Au have revealed subtle changes in the response of the total charge density to the presence of 0 atoms in the octahedral holes of these metals. In both Cu and Ag, these changes are characterized by a decrease in the magnitude of the curvature of the charge density normal to the metal-metal first-neighbor atoms. In Au there is an increase in the magnitude of this curvature. Associating the curvature of the charge density normal to the internuclear axis with the barrier to oxygen diffusion provides a consistent explanation of the difference in diffusivity of 0 through Cu, Ag, and Au. C1 US DOE,WASHINGTON,DC 20585. NASA,LANGLEY RES CTR,HAMPTON,VA 23665. RP EBERHART, ME (reprint author), COLORADO SCH MINES,DEPT MET & MAT ENGN,GOLDEN,CO 80401, USA. NR 17 TC 44 Z9 47 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 NOV 15 PY 1992 VL 46 IS 19 BP 12744 EP 12747 DI 10.1103/PhysRevB.46.12744 PG 4 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900075 ER PT J AU PERDEW, JP DEWITT, HE AF PERDEW, JP DEWITT, HE TI LOW-DENSITY LIMIT OF THE CORRELATION-ENERGY IN THE RANDOM-PHASE APPROXIMATION FOR CHARGED-PARTICLES OF ARBITRARY STATISTICS SO PHYSICAL REVIEW B LA English DT Note ID ONE-COMPONENT PLASMA; GROUND-STATE AB Within the random-phase approximation (RPA) or ring sum, the ground-state correlation energy for a uniform gas of charged particles with density parameter r(s) tends as r(s) --> infinity to (-0.803 Ry) r(s)-3/4. This limit holds for fermions, as for bosons and distinguishable particles. For electrons, the next term in the low-density expansion (of order r(s)-1) cancels the exchange energy. Corrections to RPA must cancel the r(s)-3/4 term, and can modify the r(s)-1 term. C1 TULANE UNIV,QUANTUM THEORY GRP,NEW ORLEANS,LA 70118. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP PERDEW, JP (reprint author), TULANE UNIV,DEPT PHYS,NEW ORLEANS,LA 70118, USA. NR 13 TC 2 Z9 2 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1992 VL 46 IS 19 BP 12748 EP 12749 DI 10.1103/PhysRevB.46.12748 PG 2 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900076 ER PT J AU ISAACS, ED PLATZMAN, PM ZSCHACK, P HAMALAINEN, K KORTAN, AR AF ISAACS, ED PLATZMAN, PM ZSCHACK, P HAMALAINEN, K KORTAN, AR TI INELASTIC X-RAY-SCATTERING IN SINGLE-CRYSTAL C-60 SO PHYSICAL REVIEW B LA English DT Note ID SPECTROSCOPY AB We have measured energy-loss spectra of electrons in a single crystal of C60 for several momentum transfers (0.65 less-than-or-equal-to q less-than-or-equal-to 1.15 angstrom-1) with energy resolution of 1.5 eV by the inelastic scattering of synchrotron x rays. Two features dominate the spectra; an interband transition near 5 eV due to the carbon 2p(z) electrons, and a bulk plasmon mode peaked near 30 eV, which arises from all four of the carbon valence electrons. The spectra are isotropic. C1 BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,OAK RIDGE NATL LAB,UPTON,NY 11973. RP ISAACS, ED (reprint author), AT&T BELL LABS,600 MT AVE,MURRAY HILL,NJ 07974, USA. RI Hamalainen, Keijo/A-3986-2010 OI Hamalainen, Keijo/0000-0002-9234-9810 NR 14 TC 9 Z9 9 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1992 VL 46 IS 19 BP 12910 EP 12913 DI 10.1103/PhysRevB.46.12910 PG 4 WC Physics, Condensed Matter SC Physics GA JZ039 UT WOS:A1992JZ03900120 ER PT J AU PLATZMAN, PM ISAACS, ED WILLIAMS, H ZSCHACK, P ICE, GE AF PLATZMAN, PM ISAACS, ED WILLIAMS, H ZSCHACK, P ICE, GE TI X-RAY-SCATTERING DETERMINATION OF THE DYNAMIC STRUCTURE FACTOR OF AL METAL SO PHYSICAL REVIEW B LA English DT Article ID ELECTRON-GAS; SYSTEMS AB The dynamic structure factor S(q,omega) of conduction electrons in single-crystal Al has been measured using 5.66-keV synchrotron x radiation with 1.5-eV energy resolution. These measurements confirm the existence of strong non-random-phase-approximation-like correlations in an electron liquid where band-structure effects are unimportant. C1 OAK RIDGE ASSOCIATED UNIV,BROOKHAVEN NATL LAB,UPTON,NY 11973. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP PLATZMAN, PM (reprint author), AT&T BELL LABS,MURRAY HILL,NJ 07974, USA. NR 20 TC 42 Z9 42 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 NOV 15 PY 1992 VL 46 IS 20 BP 12943 EP 12946 DI 10.1103/PhysRevB.46.12943 PG 4 WC Physics, Condensed Matter SC Physics GA KA577 UT WOS:A1992KA57700001 ER PT J AU ERIKSSON, O WILLS, JM BORING, AM AF ERIKSSON, O WILLS, JM BORING, AM TI CALCULATIONS OF CRYSTAL-STRUCTURE STABILITIES OF CE UNDER PRESSURE SO PHYSICAL REVIEW B LA English DT Article ID GROUND-STATE PROPERTIES; ELECTRONIC-STRUCTURE; CERIUM METAL; PHASE TRANSITION; VOLUME COLLAPSE; BRILLOUIN-ZONE; SPECIAL POINTS; PHOTOEMISSION; SYSTEMS; BAND AB The total energies of the observed crystal structures of Ce [face-centered cubic (fcc), orthorhombic, and body-centered tetragonal (bct)] under pressure have been calculated, using the local-density approximation. The linear-muffin-tin-orbital calculations were full potential, all electron, and fully relativistic. The experimental data for the different crystallographic transitions are well reproduced by the calculations and we have extracted two terms that are mainly responsible for the alpha --> alpha' transition: a one-electron term and a Madelung term. The alpha --> alpha' transition is driven by the increasing importance of the 4f contribution with decreasing volume. This finding is also supported by a calculation without the 4f contribution to the cohesion which yields the alpha' phase unstable. The alpha' --> bct transition is found to be somewhat more complex in nature since it is quite heavily influenced also by the 5d electrons. The calculated ground state is (correctly) found to be fcc and the equilibrium volume as well as the bulk modulus are in good agreement with experiment. The present ab initio calculation of a crystallographic phase diagram of an f electron system suggests delocalized 4f electrons exist in the high-pressure phases, including the alpha phase, of Ce. C1 LOS ALAMOS NATL LAB,CTR MAT SCI,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 43 TC 20 Z9 20 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1992 VL 46 IS 20 BP 12981 EP 12989 DI 10.1103/PhysRevB.46.12981 PG 9 WC Physics, Condensed Matter SC Physics GA KA577 UT WOS:A1992KA57700006 ER PT J AU QIU, SL JORDAN, RG BEGLEY, AM WANG, X LIU, Y RUCKMAN, MW AF QIU, SL JORDAN, RG BEGLEY, AM WANG, X LIU, Y RUCKMAN, MW TI PHOTOEMISSION-STUDIES OF THE FE 3S SPIN SPLITTING IN FE-V ALLOYS SO PHYSICAL REVIEW B LA English DT Article ID LOCAL MAGNETIC-MOMENT; CORE LEVELS; IRON; SPECTROSCOPY; SPECTRA; METALS AB The concentration dependency of the Fe 3s spin splitting in Fe-V alloys has been investigated using x-ray photoelectron spectroscopy and synchrotron radiation photoemission. Based on line-shape fits, we demonstrate that the spin splitting decreases with increasing V concentration in the same fashion as the local moment, indicating that there is a correspondence between them. It is found that the magnitude of the spin splitting, the line shape, and the intensity ratio of the two spin components are photon-energy dependent. C1 BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP QIU, SL (reprint author), FLORIDA ATLANTIC UNIV,ALLOY RES CTR,DEPT PHYS,BOCA RATON,FL 33431, USA. NR 23 TC 22 Z9 22 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1992 VL 46 IS 20 BP 13004 EP 13007 DI 10.1103/PhysRevB.46.13004 PG 4 WC Physics, Condensed Matter SC Physics GA KA577 UT WOS:A1992KA57700008 ER PT J AU SUGIYAMA, G BOWEN, C ALDER, BJ AF SUGIYAMA, G BOWEN, C ALDER, BJ TI STATIC DIELECTRIC RESPONSE OF CHARGED BOSONS SO PHYSICAL REVIEW B LA English DT Article ID GROUND-STATE; SOLID HYDROGEN; HIGH-PRESSURES; BOSE-GAS; SIGN AB The dielectric function of a charged Bose gas is determined from the response to an imposed static sinusoidal electric field. Variational and diffusion quantum Monte Carlo simulations are used to calculate the ground-state properties of the system with trial wave functions containing a parameter dependent on the amplitude and wavelength of the perturbation. The induced charge is most efficiently extracted from the difference in ground-state energies at different magnitudes of the external field, rather than directly from the expectation value of the density fluctuation operator. Results are compared to the random-phase approximation for the weakly coupled fluid and to classical lattice values at low densities where the system forms a Wigner crystal. The dielectric function is also calculated at intermediate fluid densities and the transition from positive to negative response is found to occur in the metallic regime. C1 UNIV CALIF DAVIS,DEPT APPL SCI,DAVIS,CA 95616. RP SUGIYAMA, G (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 14 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 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1992 VL 46 IS 20 BP 13042 EP 13050 DI 10.1103/PhysRevB.46.13042 PG 9 WC Physics, Condensed Matter SC Physics GA KA577 UT WOS:A1992KA57700012 ER PT J AU BARTON, JJ TERMINELLO, LJ AF BARTON, JJ TERMINELLO, LJ TI SOURCE-WAVE ANGULAR-MOMENTUM EFFECTS ON ELECTRON-DIFFRACTION PATTERNS SO PHYSICAL REVIEW B LA English DT Article ID AUGER-ELECTRON; PHOTOELECTRON DIFFRACTION; FINE-STRUCTURE; DISTRIBUTIONS; SILHOUETTES; SURFACES; SCATTERING; HOLOGRAPHY AB We use a simple model to predict when electron-emission diffraction patterns from surfaces will have peaks or dips along internuclear axes. A high angular-momentum electron wave emitted from an atom acts like an s wave (l = 0) in an extra centrifugal potential. This extra potential changes the electron's effective wave number and phase shift, altering the conditions for constructive interference when this wave scatters from nearby atoms. We demonstrate that the difference in source-wave angular momentum between Cu M2,3M4,5M4,5 Auger and Cu 3p photoelectrons explains the difference between their emission angular distributions from surfaces: the Auger-electron emission has a predominantly f-like source wave (l = 3) and destructive interference in the forward electron-scattering direction ("silhouette") while the photoelectron has lower angular momentum and constructive interference ("peak"). As long as this effect is considered, Auger-electron emission patterns can be used to determine surface structures. The unusual Auger-electron emission patterns observed by Frank et al. [Science 247, 182 (1990)] can be explained as due to high source-wave angular momentum and low electron energy. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP BARTON, JJ (reprint author), IBM CORP,THOMAS J WATSON RES CTR,YORKTOWN HTS,NY 10598, USA. NR 23 TC 11 Z9 11 U1 2 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 NOV 15 PY 1992 VL 46 IS 20 BP 13548 EP 13552 DI 10.1103/PhysRevB.46.13548 PG 5 WC Physics, Condensed Matter SC Physics GA KA577 UT WOS:A1992KA57700071 ER PT J AU COX, LE ERIKSSON, O COOPER, BR AF COX, LE ERIKSSON, O COOPER, BR TI VARIABLE-TAKEOFF-ANGLE X-RAY-PHOTOELECTRON-SPECTROSCOPY EVIDENCE FOR AN ELECTRONICALLY MODIFIED SURFACE IN A-PU SO PHYSICAL REVIEW B LA English DT Article ID GAMMA-PHASE; CE; TRANSITION; METAL; ALPHA; RECONSTRUCTIONS; CERIUM AB Photoemission spectra of an alpha-Pu surface taken at 15-degrees and 85-degrees off normal show pronounced changes attributable to an expanded delta-like surface layer. Using estimates for the inelastic mean free path of the photoelectrons and the thickness of the surface layer, we obtain spectra of the bulk and surface. The significance of this phenomenon is discussed within the context of the more familiar surface reconstructions that occur in the heavy transition metals. In contrast to the latter, the behavior of Pu is determined by the energy gain associated with 5f spin and orbital polarization rather than the increased cohesion that accompanies surface contraction. C1 LOS ALAMOS NATL LAB, CTR MAT SCI, LOS ALAMOS, NM 87544 USA. W VIRGINIA UNIV, DEPT PHYS, MORGANTOWN, WV 26506 USA. RP COX, LE (reprint author), LOS ALAMOS NATL LAB, DIV NUCL MAT & TECHNOL, LOS ALAMOS, NM 87545 USA. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 23 TC 17 Z9 17 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1992 VL 46 IS 20 BP 13571 EP 13575 DI 10.1103/PhysRevB.46.13571 PG 5 WC Physics, Condensed Matter SC Physics GA KA577 UT WOS:A1992KA57700074 ER PT J AU ERIKSSON, O COX, LE COOPER, BR WILLS, JM FERNANDO, GW HAO, YG BORING, AM AF ERIKSSON, O COX, LE COOPER, BR WILLS, JM FERNANDO, GW HAO, YG BORING, AM TI POSSIBILITY OF A DELTA-LIKE SURFACE FOR A-PU - THEORY SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; ACTINIDE METALS; BAND; SYSTEMS; CERIUM; CE; ENERGIES AB The electronic structure of a Pu square-mesh monolayer, a five-layer Pu (100)-orientation slab cut from a fcc lattice, and bulk fcc Pu have been calculated. For the monolayer calculation we allowed for spin and orbital polarization; and at all densities, from below the delta to above the alpha density, we found large spin and orbital moments. The equilibrium lattice constant for the monolayer was found to be expanded by about approximately 7%, compared to our bulk result (which is contracted approximately 7% from experiment). At both the theoretical and experimental a densities we found the five-layer slab to spin polarize, with spin moments close to that of the monolayer. Together with the experimental grazing-incidence photoemission, our results provide support for the existence of a small-moment delta-like surface state for the surface behavior of alpha plutonium. C1 LOS ALAMOS NATL LAB, DIV NEUROL, LOS ALAMOS, NM 87545 USA. W VIRGINIA UNIV, DEPT PHYS, MORGANTOWN, WV 26506 USA. UNIV CONNECTICUT, DEPT PHYS, STORRS, CT 06269 USA. RP ERIKSSON, O (reprint author), LOS ALAMOS NATL LAB, CTR MAT SCI, LOS ALAMOS, NM 87545 USA. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 38 TC 39 Z9 45 U1 1 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 NOV 15 PY 1992 VL 46 IS 20 BP 13576 EP 13583 DI 10.1103/PhysRevB.46.13576 PG 8 WC Physics, Condensed Matter SC Physics GA KA577 UT WOS:A1992KA57700075 ER PT J AU GLENDENNING, NK AF GLENDENNING, NK TI LIMITING ROTATIONAL PERIOD OF NEUTRON-STARS SO PHYSICAL REVIEW D LA English DT Article ID MILLISECOND PULSAR; STRANGE STARS; MAXIMUM MASS; MATTER; OSCILLATIONS; DISCOVERY; EQUATION; MODELS; STATE AB We seek an absolute limit on the rotational period for a neutron star as a function of its mass, based on the minimal constraints imposed by Einstein's theory of relativity, l,e Chatelier's principle, causality, and a low-density equation of state, uncertainties in which can be evaluated as to their effect on the result. This establishes a limiting curve in the mass-period plane below which no pulsar that is a neutron star can lie. For example, the minimum possible Kepler period, which is an absolute limit on rotation below which mass shedding would occur, is 0.33 ms for a M = 1. 442M. neutron star (the mass of PSR 1 913 + 16). A still lower curve, based only on the structure of Einstein's equations, limits any star whatsoever to lie in the plane above it. Hypothetical stars such as strange stars, if the matter of which they are made is self-bound in bulk at a sufficiently large equilibrium energy density, can lie in the region above the general-relativistic forbidden region, and in the region forbidden to neutron stars. RP GLENDENNING, NK (reprint author), LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720, USA. NR 50 TC 31 Z9 31 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 NOV 15 PY 1992 VL 46 IS 10 BP 4161 EP 4168 DI 10.1103/PhysRevD.46.4161 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JY244 UT WOS:A1992JY24400007 ER PT J AU AHARONIAN, FA BHATTACHARJEE, P SCHRAMM, DN AF AHARONIAN, FA BHATTACHARJEE, P SCHRAMM, DN TI PHOTON PROTON RATIO AS A DIAGNOSTIC-TOOL FOR TOPOLOGICAL DEFECTS AS THE SOURCES OF EXTREMELY HIGH-ENERGY COSMIC-RAYS SO PHYSICAL REVIEW D LA English DT Article ID TRIPLET PAIR PRODUCTION; GAMMA-RAYS; ELECTRONS; STRINGS; SPECTRUM AB The hypothesis of topological defects (from grand unified and/or Planck scales) as the sources of extremely high-energy (> 10(18) eV) cosmic rays predicts an unusually high content of gamma rays at energies E greater than or similar to 10(20) eV (gamma/p greater-than-or-equal-to 1) and E less than or similar 10(14) eV (gamma/p greater than or similar to 10(-3)). This can be used as a signature for testing the hypothesis in forthcoming experiments. C1 NASA,FERMI NATL ACCELERATOR LAB,CTR ASTROPHYS,BATAVIA,IL 60510. RP AHARONIAN, FA (reprint author), UNIV CHICAGO,5640 S ELLIS AVE,CHICAGO,IL 60637, USA. NR 35 TC 61 Z9 63 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 NOV 15 PY 1992 VL 46 IS 10 BP 4188 EP 4192 DI 10.1103/PhysRevD.46.4188 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JY244 UT WOS:A1992JY24400010 ER PT J AU KOLB, EW TKACHEV, II AF KOLB, EW TKACHEV, II TI SEMICLASSICAL CORRECTIONS TO THERMAL-ACTIVATION SO PHYSICAL REVIEW D LA English DT Article ID FALSE VACUUM; BUBBLES AB The decay of a metastable phase through the nucleation of bubbles of the true-vacuum phase can occur at a nonzero temperature through classical thermal activation, with the rate per volume P is-proportional-to exp(-F(C)/k(B)T), where F(C) is the free energy for a critical bubble and Tis the temperature. In this paper we calculate order HBAR corrections to this rate. These corrections represent processes where the field tunnels through the potential barrier starting from a state of free energy F < F(C), and provide a smooth interpolation between the high-temperature and zero-temperature decay rates. We confirm that the quantum corrections are of the same order as the classical results at large T. C1 NASA,FERMI NATL ACCELERATOR LAB,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. UNIV CHICAGO,ENRICO FERMI INST,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637. ACAD SCI RUSSIA,INST NUCL RES,MOSCOW 117312,USSR. RP KOLB, EW (reprint author), UNIV CALIF SANTA BARBARA,INST THEORET PHYS,SANTA BARBARA,CA 93106, USA. NR 13 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 15 PY 1992 VL 46 IS 10 BP 4235 EP 4241 DI 10.1103/PhysRevD.46.4235 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JY244 UT WOS:A1992JY24400016 ER PT J AU ALTY, LJ DEATH, PD DOWKER, HF AF ALTY, LJ DEATH, PD DOWKER, HF TI QUANTUM WORMHOLE STATES AND LOCAL SUPERSYMMETRY SO PHYSICAL REVIEW D LA English DT Article ID COSMOLOGICAL CONSTANT; STRING THEORY; QUANTIZATION; SUPERGRAVITY; FIELDS AB The existence of quantum wormhole states is studied in a minisuperspace model with local supersymmetry, where supergravity is coupled to a massless multiplet consisting of a spin-1/2 and complex scalar field. The geometry is taken to be that of a k = + 1 Friedmann universe, the other fields being subject to a suitable homogeneous ansatz. An integral expression is found for the wormhole ground state, and the other quantum wormhole states can be found from it by simple differential operations. The effective mass of the scalar-spin-1/2 multiplet remains zero when wormhole effects are included. C1 NASA,FERMILAB ASTROPHYS CTR,FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. RP ALTY, LJ (reprint author), UNIV CAMBRIDGE,DEPT APPL MATH & THEORET PHYS,SILVER ST,CAMBRIDGE CB3 9EW,ENGLAND. NR 23 TC 21 Z9 21 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 15 PY 1992 VL 46 IS 10 BP 4402 EP 4412 DI 10.1103/PhysRevD.46.4402 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JY244 UT WOS:A1992JY24400031 ER PT J AU DOREY, N AF DOREY, N TI MULTIINSTANTON VALLEYS IN THE O(3) SIGMA-MODEL SO PHYSICAL REVIEW D LA English DT Article ID FERMION-NUMBER VIOLATION; SECTOR; AMPLITUDES; BREAKDOWN AB An explicit construction is given for valleys in the configuration space of an arbitrary number of instanton-anti-instanton pairs for the O(3) nonlinear sigma model in two dimensions. The sigma-model action is supplemented by an explicit conformal-symmetry-breaking term and the multi-instanton valleys are used to examine the relative importance of single- and multi-instanton contributions to anomalous scattering. Numerical solutions to the saddle-point equations for the cross section are presented which support the existence of a critical energy above which the dilute instanton gas approximation breaks down. The relevance of these results to the problem of multi-instanton corrections to processes which violate baryon number in the standard model is discussed. RP DOREY, N (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,T-8 MS B285,LOS ALAMOS,NM 87545, USA. NR 22 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 15 PY 1992 VL 46 IS 10 BP 4668 EP 4676 DI 10.1103/PhysRevD.46.4668 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JY244 UT WOS:A1992JY24400050 ER PT J AU COOK, DN MA, D PON, NG HEARST, JE AF COOK, DN MA, D PON, NG HEARST, JE TI DYNAMICS OF DNA SUPERCOILING BY TRANSCRIPTION IN ESCHERICHIA-COLI SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE DNA GYRASE; TOPOISOMERASE-I; TOPOLOGY; GENE EXPRESSION ID TOPOISOMERASE-I MUTANTS; RNA-POLYMERASE; GYRASE GENES; PLASMID DNA; MUTATIONS; TEMPLATE; PROTEIN; PBR322; INVIVO; PURIFICATION AB The relative rotation between RNA polymerase and DNA during transcription elongation can lead to supercoiling of the DNA template. However, the variables that influence the efficiency of supercoiling by RNA polymerase in vivo are poorly understood, despite the importance of supercoiling for DNA metabolism. We describe a model system to measure the rate of supercoiling by transcription and to estimate the rates of topoisomerase turnover in Escherichia coli. Transcription in a strain lacking topoisomerase I can lead to optimal supercoiling, wherein nearly one positive and one negative superturn are produced for each 10.4 base pairs transcribed. This rapid efficient supercoiling is observed during transcription of membrane-associated gene products, encoded by tet (the gene for tetracycline resistance) and phoA (the gene for E. coli alkaline phosphatase), when the genes are oppositely oriented. Replacement of tet by cat, the gene from Tn9 encoding resistance to chloramphenicol, whose gene product is soluble in the cytosol, reduces the efficiency of supercoiling by RNA polymerase. In a wild-type topoisomerase background, both gyrase and topoisomerase I are kinetically competent to relieve superturns produced by transcription. These results suggest that the level of DNA supercoiling in vivo is probably determined by topoisomerase activity, not by transcription. C1 LAWRENCE BERKELEY LAB,DIV STRUCT BIOL,BERKELEY,CA 94720. RP COOK, DN (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,MELVIN CALVIN LAB,BERKELEY,CA 94720, USA. FU FDA HHS [FD 8R1 GM 41911A-03-NF-03/92] NR 30 TC 54 Z9 54 U1 0 U2 3 PU NATL ACAD PRESS 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 NOV 15 PY 1992 VL 89 IS 22 BP 10603 EP 10607 DI 10.1073/pnas.89.22.10603 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JY874 UT WOS:A1992JY87400009 PM 1332053 ER PT J AU SHYAMALA, G GUIOT, MC AF SHYAMALA, G GUIOT, MC TI ACTIVATION OF KAPPA-B-SPECIFIC PROTEINS BY ESTRADIOL SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID MAJOR HISTOCOMPATIBILITY COMPLEX; DEPENDENT REGULATORY ELEMENT; DNA-BINDING SUBUNIT; GLUCOCORTICOID RECEPTOR; OVALBUMIN GENE; NUCLEAR FACTOR; C-JUN; TRANSCRIPTION; SEQUENCE; RECOGNIZE AB The kappaB enhancer serves as a recognition site for the nuclear transcription factor NF-kappaB and other kappaB-specific proteins which are activated in many cell types in response to a variety of extracellular signals. But a steroid-dependent activation of NF-kappaB or any other kappaB-specific protein has not previously been reported, to our knowledge. In this report we demonstrate that estrogen can activate kappaB-specific protein in its target tissue, uterus. We have done this by analyzing the interaction of nuclear extracts with kappaB enhancers, using DNA mobility shift assays. The activation by estradiol was time dependent, reaching a maximum at approximately 2 hr after steroid treatment, and was not inhibited by prior cycloheximide treatment. The protein-DNA complexes formed in response to estradiol did not contain NF-kappaB and, when compared with other kappaB enhancer motifs, had a higher affinity to the kappaB enhancer corresponding to the PRDII element present in duplicate motifs. These protein-DNA complexes also did not appear to contain estrogen receptor, since antibodies to estrogen receptor were without any effect on either their formation or their mobility. The protein-DNA complexes formed in response to estradiol, however, exhibited a high affinity for the estrogen-responsive element, suggesting the participation of an estrogen-receptor-like molecule in the DNA binding. In contrast, the protein-DNA complexes formed constitutively contained NF-kappaB, had equivalent affinities to various kappaB enhancers, and did not have a high affinity for the estrogen-responsive element. On the basis of these findings, we propose that estrogen-dependent activation of the as-yet-unidentified kappaB-specific protein involves the association of this protein with an estrogen-receptor-related molecule and binding of the resulting complex to PRDII. The high affinity and specificity of this binding to PRDII suggests that this may serve as a composite regulatory element in mediating estrogen-dependent gene expression. The potential significance of such a mechanism for steroid hormone action is discussed. C1 LAWRENCE BERKELEY LAB,DIV CELLULAR & MOLEC BIOL,BERKELEY,CA 94720. SIR MORTIMER B DAVIS JEWISH HOSP,LADY DAVIS INST MED RES,MONTREAL H3T 1E2,QUEBEC,CANADA. NR 34 TC 33 Z9 33 U1 0 U2 0 PU NATL ACAD PRESS 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 NOV 15 PY 1992 VL 89 IS 22 BP 10628 EP 10632 DI 10.1073/pnas.89.22.10628 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JY874 UT WOS:A1992JY87400014 PM 1438258 ER PT J AU HAINFELD, JF AF HAINFELD, JF TI URANIUM-LOADED APOFERRITIN WITH ANTIBODIES ATTACHED - MOLECULAR DESIGN FOR URANIUM NEUTRON-CAPTURE THERAPY SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE CANCER; IMMUNOTHERAPY; APOFERRITIN; CHELATION ID MONOCLONAL-ANTIBODY; BORON; MELANOMA; BINDING; TUMORS; SIZE AB A method is described to deliver U-235 to tumors; the isotope would then be fissioned by incident neutrons, producing localized lethal radiation sufficient for therapy. Apoferritin was loaded with an average of almost-equal-to 800 U-238 atoms per molecule. Stability of the loaded apoferritin in solution was improved, so that only 8% loss of uranium occurred after 8 days at pH 7. Fab' antibody fragments were covalently attached to the uranium-loaded apoferritin, and the immunoreactivity of the conjugate was 92% of that for antibody alone. Such bio-uranium constructions should provide significant advantages over boronated antibodies to meet the requirements for clinical neutron-capture therapy. RP HAINFELD, JF (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. NR 26 TC 82 Z9 84 U1 1 U2 12 PU NATL ACAD PRESS 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 NOV 15 PY 1992 VL 89 IS 22 BP 11064 EP 11068 DI 10.1073/pnas.89.22.11064 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JY874 UT WOS:A1992JY87400104 PM 1438316 ER PT J AU NISHIMURA, C LIU, CT AF NISHIMURA, C LIU, CT TI EFFECTS OF ALLOY STOICHIOMETRY ON ENVIRONMENTAL EMBRITTLEMENT IN L12-ORDERED (CO,FE)3V ALLOYS SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article ID GRAIN-BOUNDARY STRENGTH; MECHANICAL-PROPERTIES; HYDROGEN EMBRITTLEMENT; CO3TI POLYCRYSTALS; ORDERED ALLOYS; FRACTURE; BORON; NI3AL; ADDITIONS; DUCTILITY C1 NATL RES INST MET,TOKYO 153,JAPAN. RP NISHIMURA, C (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831, USA. NR 31 TC 8 Z9 8 U1 0 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 NOV 15 PY 1992 VL 27 IS 10 BP 1307 EP 1311 DI 10.1016/0956-716X(92)90075-P PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA JW196 UT WOS:A1992JW19600010 ER PT J AU PIKE, LM LIU, CT AF PIKE, LM LIU, CT TI THE ROLE OF BORON IN SUPPRESSING ENVIRONMENTAL EMBRITTLEMENT IN L12-ORDERED (CO,FE)3V SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article ID BASE L12 ALLOYS; HYDROGEN EMBRITTLEMENT; MECHANICAL-PROPERTIES; GRAIN-BOUNDARIES; NI3AL; DUCTILITY; FRACTURE; FEAL C1 OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831. OI Liu, Chain Tsuan/0000-0001-7888-9725 NR 22 TC 5 Z9 5 U1 0 U2 6 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 NOV 15 PY 1992 VL 27 IS 10 BP 1313 EP 1317 DI 10.1016/0956-716X(92)90076-Q PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA JW196 UT WOS:A1992JW19600011 ER PT J AU BANSENAUER, BA CREIGHTON, JR AF BANSENAUER, BA CREIGHTON, JR TI A THERMAL-DESORPTION INVESTIGATION OF ARSINE CHEMISORPTION ON GA-RICH AND AS-RICH GAAS(100) SURFACES SO SURFACE SCIENCE LA English DT Article ID SCANNING TUNNELING MICROSCOPY; GAAS(001); STOICHIOMETRY; ADSORPTION; INSITU; LEED; AES AB We have studied the low temperature chemisorption of arsine on the Ga and As-rich surfaces of GaAs(100) using temperature programmed desorption. Arsine desorbing from the "(4 x 6)" Ga-rich surface desorbs from both molecular (T(p) almost-equal-to 165 K) and recombinative states (T(p) = 290 and 380 K) with an estimated saturation coverage of 0.09 ML, where 1 ML = 6.26 x 10(14) atoms/cm2. A very small amount of arsine is irreversibly adsorbed (approximately 0.01 ML) as evidenced by hydrogen desorption at about 520 K. This small arsine coverage suggests that most of the Ga atoms on the Ga-rich surface are not available for arsine chemisorption. On the c(2 x 8)/(2 x 4) As-rich GaAs(100) surface roughly two times more arsine desorbs compared to the Ga-rich surface and new desorption states are seen around 230 and 460 K. This increased arsine coverage suggests that most of the exposed Ga atoms on the As-rich surface are available for chemisorption. Approximately the same amount of arsine irreversibly decomposes on the c(2 x 8)/(2 x 4) As-rich surface (compared to the Ga-rich surface), but H-2 desorption occurs from a broad peak that is centered around 600 K. On the c(4 x 4) As-rich surface, arsine decomposition is not observed and only a small amount of arsine desorption is detected. This result is to be expected since there are no exposed Ga atoms on the c(4 x 4) surface. RP BANSENAUER, BA (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. RI Schaff, William/B-5839-2009 NR 24 TC 12 Z9 12 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 NOV 15 PY 1992 VL 278 IS 3 BP 317 EP 325 DI 10.1016/0039-6028(92)90668-V PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA JX587 UT WOS:A1992JX58700010 ER PT J AU RODRIGUEZ, JA AF RODRIGUEZ, JA TI BONDING AND DECOMPOSITION OF THIOPHENE, SULFHYDRYL, THIOMETHOXY AND PHENYL THIOLATE ON MO SURFACES SO SURFACE SCIENCE LA English DT Article ID ABSORPTION FINE-STRUCTURE; SINGLE-CRYSTAL SURFACE; CATALYTIC HYDRODESULFURIZATION; INTERMEDIATE NEGLECT; COPPER SURFACES; METAL-SURFACES; ADSORPTION; CHEMISORPTION; CU(100); HYDROGEN AB The bonding of thiophene (C4H4S), sulfhydryl (HS), thiomethoxy (CH3S) and phenyl thiolate (C6H5S) to molybdenum surfaces has been examined employing MO-SCF calculations (INDO/1) and metal clusters of limited size (Mo(n), n = 13-19 atoms). The calculations indicate that the preferred binding sites for the RS species on Mo(100) are the four-fold hollows. The bonding mechanism of thiophene involves a large charge transfer from the S-lone pairs of the molecule (6a1 and 2b1 orbitals) into the surface, and electron transfer from the substrate into the C-S antibonding 3b1 orbital of the adsorbate. Adsorption of thiophene on a hollow site leads to a large weakening in the strength of the C-S and C-H bonds, producing a precursor for the dissociation of the molecule. HS, CH3S and C6H5S behave as electron acceptors when bonded to Mo. For these species, the chemisorption bond is dominated by the interaction between the LUMO of the adsorbate and the Mo(4d,5s) bands. The results of a thermochemical analysis indicate that reactions which involve the cleavage of H-S and C-S bonds of alkanethiols on Mo (RSH(g) --> S(a) + RH(g)) are very exothermic (-DELTAH = 40-50 kcal/mol). The thermodynamics suggests that C-S bond breaking should be the most difficult step in the desulfurization process. The hydrogenolysis of the C-S bond (RS(a) + H(a) --> S(a) + RH(g)) is approximately 12 kcal/mol more exothermic for CH3S than for C6H5S. RP RODRIGUEZ, JA (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. NR 81 TC 50 Z9 50 U1 1 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 NOV 15 PY 1992 VL 278 IS 3 BP 326 EP 338 DI 10.1016/0039-6028(92)90669-W PG 13 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA JX587 UT WOS:A1992JX58700011 ER PT J AU BAFRALI, R BELL, AT AF BAFRALI, R BELL, AT TI INTERACTIONS OF H2 AND NH3 WITH MO(100) AND MO(100)-C(2X2)N SURFACES SO SURFACE SCIENCE LA English DT Article ID LEWIS-ACIDS; CHEMISORPTION; AMMONIA; MOLYBDENUM; HYDROGEN; OXYGEN; BASES AB The interactions of H-2 and NH3 With Mo(100) and Mo(100)-c(2 x 2)N surfaces were studied using temperature programmed desorption and Auger electron spectroscopies. For a clean Mo(100) surface, the initial sticking coefficient is 1.0 and the maximum adsorption capacity is 2.0 ML. On the nitrided surface, the sticking coefficient decreases to 0.4 and the maximum capacity decreases to 0.5 ML. The initial sticking coefficient for NH3 on Mo(100) is 0.36, and the saturation adsorption capacity is 0.6 ML. Nitriding the surface reduces the initial sticking coefficient to 0.24 and the saturation capacity to 0.35 ML. Temperature programmed desorption studies show that adsorbed NH3 undergoes desorption and concurrent decomposition, the extent of decomposition being much less significant on the Mo(100)-c(2 x 2)N than on the Mo(100) surface. D2/NH3 coadsorption studies reveal that NH3 decomposition proceeds via a stepwise dehydrogenation process. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. RP BAFRALI, R (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT DIV MAT SCI,BERKELEY,CA 94720, USA. NR 20 TC 26 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 NOV 15 PY 1992 VL 278 IS 3 BP 353 EP 363 DI 10.1016/0039-6028(92)90671-R PG 11 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA JX587 UT WOS:A1992JX58700013 ER PT J AU ROSS, JV BAUER, SJ AF ROSS, JV BAUER, SJ TI SEMIBRITTLE DEFORMATION OF ANHYDRITE HALITE SHEAR ZONES SIMULATING MYLONITE FORMATION SO TECTONOPHYSICS LA English DT Article ID DYNAMIC RECRYSTALLIZATION; MECHANICAL-BEHAVIOR; ROCKS; CREEP; QUARTZITES; FABRICS; EXAMPLE; WATER; FLOW AB A series of new shear experiments on similar volume mixes of anhydrite and halite have been run at 100-degrees and 400-degrees-C, at the same constant loading rate and constant confining pressure of 200 MPa. Increasing temperature is found to decrease the viscosity contrast between anhydrite and halite, the ''hard'' and ''soft'' phases, respectively. The mechanical response is similar at all temperatures, regardless of volume proportions of mix; an initial high stress steady state portion of the stress/strain curve is followed by a stress drop and then by a second steady state stress interval, at a much lower value. That is nearly equal to the strength of the softer phase, halite. Individual mineral behaviours and deformation mechanisms appear to correlate with specific portions of the stress/strain curve as the fabric(s) evolve with increasing strain. Mechanism(s) of strain accomodation at all temperatures is semi-brittle; deformation mechanisms change gradually with conditions, with shear dominated by stable sliding along R1 and R2 shear fracures (especially in mixes of high anhydrite content) at 100-degrees-C, while homogeneous ductile flow along S- and C-surfaces is observed at 400-degrees-C in all variations of composition. These features are very similar to those observed in natural shear zones. C1 SANDIA NATL LABS,DEPT UNDERGROUND STORAGE TECHNOL 6113,ALBUQUERQUE,NM 87185. RP ROSS, JV (reprint author), UNIV BRITISH COLUMBIA,DEPT GEOL SCI,6339 STORES RD,VANCOUVER V6T 2Z4,BC,CANADA. NR 38 TC 9 Z9 11 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-1951 J9 TECTONOPHYSICS JI Tectonophysics PD NOV 15 PY 1992 VL 213 IS 3-4 BP 303 EP 320 DI 10.1016/0040-1951(92)90460-N PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KF102 UT WOS:A1992KF10200002 ER PT J AU DEBROUCKERE, G FELLER, D KOOT, JJA BERTHIER, G AF DEBROUCKERE, G FELLER, D KOOT, JJA BERTHIER, G TI CONFIGURATION-INTERACTION CALCULATIONS ON THE X-SIGMA-1+ GROUND-STATE AND LOW-LYING A-PI-1 AND DELTA-1 EXCITED-STATES OF THE PN MOLECULE .1. POTENTIAL-ENERGY CURVE OF THE X-SIGMA-1+ STATE OF PN - MISCELLANEOUS SPECTROSCOPIC OBSERVABLES SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID TRANSITION; LIFETIMES; SPECTRUM; MOMENTS AB A series of multireference configuration interaction (CI) calculations using an extended Gaussian basis set have been performed on the X 1SIGMA+ ground state of the PN molecule in order to accurately determine the potential energy surface in the vicinity of the minimum. With the help of this curve a wide assortment of spectroscopic observables have been computed. The overall agreement with experiment is good. Marked correlation energy effects are found for the electric dipole/quadrupole moments and nitrogen nuclear coupling. Pure rotational excitations calculated by means of the numerical solutions of the radial Schrodinger equation are found to be in quite good agreement with experiment. Average values of the electric dipole moment over the first vibrational levels have been derived and the trend exhibited by the experimental data is well reflected by the theoretical results. Vibrorotational transitions, pure vibrational and vibrorotational lifetimes have also been determined which, to date, have not been determined experimentally. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. ACAD COMP SERV, 1098 SJ AMSTERDAM, NETHERLANDS. INST BIOL PHYS CHIM, BIOCHIM THEOR LAB, F-75005 PARIS, FRANCE. RP DEBROUCKERE, G (reprint author), UNIV AMSTERDAM, DEPT PHYS & ASTRON, VALCKENIERSTR 65, 1018 XE AMSTERDAM, NETHERLANDS. NR 36 TC 16 Z9 16 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD NOV 14 PY 1992 VL 25 IS 21 BP 4433 EP 4445 PG 13 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA JY815 UT WOS:A1992JY81500011 ER PT J AU CARLSON, D WILLIAMS, J AF CARLSON, D WILLIAMS, J TI SUPERCONDUCTORS GO ORGANIC SO NEW SCIENTIST LA English DT Article RP CARLSON, D (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 1 TC 3 Z9 3 U1 0 U2 3 PU NEW SCIENTIST PUBL EXPEDITING INC PI ELMONT PA 200 MEACHAM AVE, ELMONT, NY 11003 SN 0262-4079 J9 NEW SCI JI New Sci. PD NOV 14 PY 1992 VL 136 IS 1847 BP 26 EP 30 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JY284 UT WOS:A1992JY28400037 ER PT J AU NAGY, JO WANG, P GILBERT, JH SCHAEFER, ME HILL, TG CALLSTROM, MR BEDNARSKI, MD AF NAGY, JO WANG, P GILBERT, JH SCHAEFER, ME HILL, TG CALLSTROM, MR BEDNARSKI, MD TI CARBOHYDRATE MATERIALS BEARING NEURAMINIDASE-RESISTANT C-GLYCOSIDES OF SIALIC-ACID STRONGLY INHIBIT THE INVITRO INFECTIVITY OF INFLUENZA-VIRUS SO JOURNAL OF MEDICINAL CHEMISTRY LA English DT Letter ID N-ACETYLNEURAMINIC ACID; SIALOSIDE INHIBITORS; HEMAGGLUTININ; RECOGNITION; RECEPTOR; DERIVATIVES C1 LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. GLYCOMED,DEPT MICROBIOL & IMMUNOL,ALAMEDA,CA 94501. OHIO STATE UNIV,DEPT CHEM,COLUMBUS,OH 43210. RP NAGY, JO (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720, USA. FU NIGMS NIH HHS [R29 GM43037-02] NR 24 TC 55 Z9 56 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-2623 J9 J MED CHEM JI J. Med. Chem. PD NOV 13 PY 1992 VL 35 IS 23 BP 4501 EP 4502 DI 10.1021/jm00101a031 PG 2 WC Chemistry, Medicinal SC Pharmacology & Pharmacy GA JY974 UT WOS:A1992JY97400031 PM 1447751 ER PT J AU ZHANG, Y RAMAN, N BAILEY, JK BRINKER, CJ CROOKS, RM AF ZHANG, Y RAMAN, N BAILEY, JK BRINKER, CJ CROOKS, RM TI A NEW SOL-GEL ROUTE FOR THE PREPARATION OF NANOMETER-SCALE SEMICONDUCTOR PARTICLES THAT EXHIBIT QUANTUM OPTICAL BEHAVIOR SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Letter ID PHOTOPHYSICAL PROPERTIES; ELECTRONIC STATES; CRYSTALLITES; CLUSTERS; CDS; MOLECULES; SULFIDE; GLASSES; METAL; ZNS AB A new sol-gel route for the preparation of nanometer-scale ZnS semiconductor particles that display quantum optical behavior is reported. Exploiting the scaling relationship between size and density of fractal polymeric precursors, films are prepared with narrow pore size distributions that serve as templates to constrain the growth of ZnS semiconductor particles. Blue shifts of the ZnS absorption threshold indicate that the particle size is reduced from 4.6 to 2.3 nm as the pore size is reduced from 3.5 to less-than-or-equal-to 2.0 nm. Results obtained using transmission electron microscopy are in general agreement with the spectroscopic results. This is a general approach for preparing thin-film nanocomposite materials with tailored optical and/or electronic properties. C1 UNIV NEW MEXICO,NSF,CTR MICRO ENGINEERED CERAM,ALBUQUERQUE,NM 87131. UNIV NEW MEXICO,DEPT CHEM,ALBUQUERQUE,NM 87131. SANDIA NATL LABS,DEPT 1846,ALBUQUERQUE,NM 87185. NR 33 TC 42 Z9 49 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 NOV 12 PY 1992 VL 96 IS 23 BP 9098 EP 9100 DI 10.1021/j100202a004 PG 3 WC Chemistry, Physical SC Chemistry GA JX921 UT WOS:A1992JX92100004 ER PT J AU LIU, AD SAUER, MC JONAH, CD TRIFUNAC, AD AF LIU, AD SAUER, MC JONAH, CD TRIFUNAC, AD TI MECHANISM OF THE FORMATION OF TRANSIENT AROMATIC RADICAL CATIONS IN ALCOHOLS - LASER FLASH-PHOTOLYSIS AND PULSE-RADIOLYSIS STUDIES SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID CHARGE-TRANSFER EXCITATION; PHOTOIONIZATION; LIQUIDS; HYDROCARBONS; CONDUCTIVITY; IONIZATION AB A product of the reaction of SF6 with a solvated electron in an alcohol (presumably SF5.) reacts with an aromatic solute molecule such as anthracene, perylene, naphthalene, or hexamethylbenzene to form aromatic radical cations. This reaction depends on both the ionization potential of the aromatic solute molecule and the polarity of the solvent. The rates of these reactions are (except for naphthalene) in the range of (1-10) X 10(9) M-1 s-1. The reaction of the aromatic molecule (except for naphthalene) with SF5. appears to have two pathways, one of which leads to the radical cation and a second that forms an undetermined product. C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. NR 25 TC 2 Z9 2 U1 1 U2 2 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 NOV 12 PY 1992 VL 96 IS 23 BP 9293 EP 9298 DI 10.1021/j100202a043 PG 6 WC Chemistry, Physical SC Chemistry GA JX921 UT WOS:A1992JX92100043 ER PT J AU GARDIN, DE SOMORJAI, GA AF GARDIN, DE SOMORJAI, GA TI VIBRATIONAL-SPECTRA AND THERMAL-DECOMPOSITION OF METHYLAMINE AND ETHYLAMINE ON NI(111) SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID SURFACE-CHEMISTRY; ALKYL AMINES; ADSORPTION; CH3NH2; TRIMETHYLAMINE; REDUCTION; COMPLEXES; NI(100); PD(111); W(100) AB The bonding and geometry of methylamine (CH3NH2) and ethylamine (CH3CH2NH2) on Ni(111) have been investigated with high-resolution electron energy loss vibrational spectroscopy (HREELS). Both amines adsorb molecularly at 150 K through the nitrogen lone pair. Significant metal-hydrogen interactions in the alkyl chain were indicated by "softened" C-H stretching modes with frequencies shifted to 2660-2680 cm-1. Temperature-programmed desorption (TPD) and HREELS were used to monitor their desorption and thermal decomposition on the Ni(111) surface. Both CH3NH2 and CH3CH2NH2 are dehydrogenated in the temperature range 300-400 K. CH3NH2 is dehydrogenated to HCN at about 330 K, which further decomposes above 360 K. CH3CH2NH2 is dehydrogenated to CH3CN, initially by alpha-C-H bond scission, leading to desorption of that molecule at 350 K. On the basis of our spectra, we propose a mechanism for the dehydrogenation processes of CH3NH2 and CH3CH2NH2 on Ni(111). C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,CTR ADV MAT,1 CYCLOTRON RD,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. NR 33 TC 65 Z9 65 U1 0 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD NOV 12 PY 1992 VL 96 IS 23 BP 9424 EP 9431 DI 10.1021/j100202a067 PG 8 WC Chemistry, Physical SC Chemistry GA JX921 UT WOS:A1992JX92100067 ER PT J AU LEITCH, MJ BAER, HW KLEIN, A MISHRA, CS WEINFELD, Z PIASETZKY, E EZRA, Y WEISS, R ALLGOWER, C COMFORT, JR TINSLEY, J WRIGHT, DH AF LEITCH, MJ BAER, HW KLEIN, A MISHRA, CS WEINFELD, Z PIASETZKY, E EZRA, Y WEISS, R ALLGOWER, C COMFORT, JR TINSLEY, J WRIGHT, DH TI ENERGY-DEPENDENCE OF LOW-ENERGY PION DOUBLE-CHARGE-EXCHANGE ON THE CALCIUM ISOTOPES SO PHYSICS LETTERS B LA English DT Article ID NUCLEUS ELASTIC-SCATTERING; SHELL-MODEL; C-14; RESONANCE AB The forward angle differential cross sections of (pi+, pi-) reactions on the calcium isotopes to the double-isobaric-analog (DIAS) and ground states (GS) were measured between 2 5 and 6 5 MeV. These low-energy cross sections are up to an order of magnitude larger than those at resonance energies. The forward-angle excitation functions of Ca-42, Ca-44 DIAS and Ca-44 GS transitions peak around 50 MeV. The 48Ca DIAS cross section exhibits a minimum at about 50 MeV and that for the GS has a peak which is shifted to lower energy with a smaller cross section than that of the other nuclei. The observed behaviour is inconsistent with theoretical expectations. C1 TEL AVIV UNIV,RAYMOND & BEVERLY SACKLER FAC EXACT SCI,IL-69978 TEL AVIV,ISRAEL. ARIZONA STATE UNIV,TEMPE,AZ 85287. TRIUMF,VANCOUVER V6T 2A3,BC,CANADA. RP LEITCH, MJ (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 32 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD NOV 12 PY 1992 VL 294 IS 2 BP 157 EP 161 DI 10.1016/0370-2693(92)90676-U PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX564 UT WOS:A1992JX56400001 ER PT J AU KILGORE, WB AF KILGORE, WB TI THE EQUIVALENCE THEOREM IN THE ABELIAN HIGGS THEORY SO PHYSICS LETTERS B LA English DT Article ID GAUGE THEORIES AB The equivalence theorem relates the high energy scattering amplitudes of longitudinal vector bosons to the amplitudes for the corresponding unphysical Goldstone bosons. The theorem receives renormalization-scheme and gauge dependent quantum corrections. In the abelian Higgs theory, it is shown that the theorem can be formulated in such a way that quantum corrections vanish to all orders in perturbation theory. C1 LAWRENCE BERKELEY LAB,THEORET PHYS GRP,BERKELEY,CA 94720. RP KILGORE, WB (reprint author), LAWRENCE BERKELEY LAB,DEPT PHYS,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 10 TC 24 Z9 24 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 NOV 12 PY 1992 VL 294 IS 2 BP 257 EP 262 DI 10.1016/0370-2693(92)90691-V PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX564 UT WOS:A1992JX56400016 ER PT J AU WARREN, MS QUINN, PJ SALMON, JK ZUREK, WH AF WARREN, MS QUINN, PJ SALMON, JK ZUREK, WH TI DARK HALOS FORMED VIA DISSIPATIONLESS COLLAPSE .1. SHAPES AND ALIGNMENT OF ANGULAR-MOMENTUM SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, FORMATION; GALAXIES, KINEMATICS AND DYNAMICS; METHODS, NUMERICAL ID N-BODY SIMULATIONS; INITIAL CONDITIONS; GALACTIC HALOES; GALAXIES; MATTER; UNIVERSE; FLUCTUATIONS; ROTATION; CODE AB We use N-body simulations on highly parallel supercomputers to study the structure of Galactic dark matter halos. The systems form by gravitational collapse from scale-free and more general Gaussian initial density perturbations in an expanding 400 Mpc3 spherical slice of an Einstein-deSitter universe. We use N approximately 10(6) and a force softening epsilon = 5 kpc in most of our models. We analyze the structure and kinematics of the approximately 10(2) largest relaxed halos in each of 10 separate simulations. A typical halo is a triaxial spheroid which tends to be more often prolate than oblate. These shapes are maintained by anisotropic velocity dispersion rather than by angular momentum (spin parameter lambda approximately 0.05). Nevertheless, there is a significant tendency for the total angular momentum vector to be aligned with the minor axis of the density distribution. These features (halo shape and orientation with respect to angular momentum) are maintained throughout the virialized portion of the halo. We have also studied the sensitivity of the shapes to the smoothing length epsilon and find that halos tend to become less prolate at small radii for epsilon = 1 kpc. Numerical and astrophysical consequences of this result are briefly considered. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. MT STROMLO & SIDING SPRING OBSERV,PB WESTON CREEK,ACT 2611,AUSTRALIA. CALTECH,CONCURRENT SUPERCOMPUT FACIL,PASADENA,CA 91125. RI Quinn, Peter/B-3638-2013; OI Warren, Michael/0000-0002-1218-7904 NR 46 TC 423 Z9 427 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 NOV 10 PY 1992 VL 399 IS 2 BP 405 EP 425 DI 10.1086/171937 PN 1 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV806 UT WOS:A1992JV80600008 ER PT J AU MEYER, BS MATHEWS, GJ HOWARD, WM WOOSLEY, SE HOFFMAN, RD AF MEYER, BS MATHEWS, GJ HOWARD, WM WOOSLEY, SE HOFFMAN, RD TI R-PROCESS NUCLEOSYNTHESIS IN THE HIGH-ENTROPY SUPERNOVA BUBBLE SO ASTROPHYSICAL JOURNAL LA English DT Article DE NUCLEAR REACTIONS; NUCLEOSYNTHESIS; ABUNDANCES; SUPERNOVAE, GENERAL ID BETA-DELAYED FISSION; NEUTRON-RICH NUCLEI; DECAY HALF-LIVES; STAR MATTER; COLLAPSE; MODEL; DECOMPRESSION; ELEMENTS; EMISSION; OXYGEN AB We show that the high-temperature, high-entropy evacuated region outside the recent neutron star in a core-collapse supernova may be an ideal r-process site. In this high-entropy environment it is possible that most nucleons are in the form of free neutrons or bound into alpha particles. Thus, there can be many neutrons per seed nucleus even though the material is not particularly neutron rich. The predicted amount of r-process material ejected per event from this environment agrees well with that required by simple galactic evolution arguments. When averaged over regions of different neutron excess in the supernova ejecta, the calculated r-process abundance curve can give a good representation of the solar-system r-process abundances as long as the entropy per baryon is sufficiently high. Neutrino irradiation may aid in smoothing the final abundance distribution. C1 LAWRENCE LIVERMORE NATL LAB, GEN STUDIES GRP, LIVERMORE, CA 94550 USA. UNIV CALIF SANTA CRUZ, BOARD STUDIES ASTRON & ASTROPHYS, SANTA CRUZ, CA 95064 USA. RP CLEMSON UNIV, DEPT PHYS & ASTRON, CLEMSON, SC 29634 USA. NR 60 TC 257 Z9 259 U1 1 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1992 VL 399 IS 2 BP 656 EP 664 DI 10.1086/171957 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV806 UT WOS:A1992JV80600028 ER PT J AU BEREZHIANI, ZG RATTAZZI, R AF BEREZHIANI, ZG RATTAZZI, R TI INVERTED RADIATIVE HIERARCHY OF QUARK MASSES SO JETP LETTERS LA English DT Article ID STRONG CP-PROBLEM; SYMMETRY; AXION AB We suggest that the mass hierarchy is first generated in a sector of heavy isosinglet fermions due to radiative effects and then projected in the inverted way to the usual quarks by means of a universal seesaw. The simple left-right symmetric gauge model is presented with the P- and CP-parities and the exact isotopic symmetry, which are softly (or spontaneously) broken in the Higgs potential. This approach naturally explains the observed pattern of quark masses and mixing, providing the quantitatively correct formula for the Cabibbo angle. Top quark is predicted to be in the 90-150 GeV range. C1 GEORGIAN ACAD SCI,INST PHYS,TBILISI,REP OF GEORGIA. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP BEREZHIANI, ZG (reprint author), UNIV MUNICH,SEKT PHYS,W-8000 MUNICH 2,GERMANY. RI Berezhiani, Zurab/H-7221-2016; OI Berezhiani, Zurab/0000-0002-4156-1686; Rattazzi, Riccardo/0000-0003-0276-017X NR 13 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 0021-3640 J9 JETP LETT+ JI Jetp Lett. PD NOV 10 PY 1992 VL 56 IS 9 BP 429 EP 434 PG 6 WC Physics, Multidisciplinary SC Physics GA KF749 UT WOS:A1992KF74900004 ER PT J AU ZAGAL, J PAEZ, M TANAKA, AA DOSSANTOS, JR LINKOUS, CA AF ZAGAL, J PAEZ, M TANAKA, AA DOSSANTOS, JR LINKOUS, CA TI ELECTROCATALYTIC ACTIVITY OF METAL PHTHALOCYANINES FOR OXYGEN REDUCTION SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Article ID ADSORBED TETRASULFONATED PHTHALOCYANINES; GRAPHITE-ELECTRODES; COBALT PHTHALOCYANINE; IRON PHTHALOCYANINE; CATHODIC REDUCTION; DIOXYGEN REDUCTION; AQUEOUS-SOLUTIONS; EXPERIMENTAL PART; O-2 REDUCTION; CATALYSIS AB A comparative study of the electrocatalytic activity of metallophthalocyanines for O2 reduction in alkaline and acid media was conducted using H2Pc, VOTsPc, CrTsPc, MnTsPc, MnPc, FeTsPc, FePc, FeMeOPc, CoTsPc, CoPc, CoMeOPc, CoTnPc and ZnTsPc adsorbed on OPG electrodes. Different electron-transfer mechanisms for O2 reduction were found depending on the position of the M(III)/M(II) redox couples on the potential scale and the onset potential for O2 reduction. Volcano-shaped correlations between the redox potential and the O2 catalytic activity were observed. This has been rationalized on the basis of the redox catalysis concept and in terms of molecular orbital theory considerations. C1 UNIV SAO PAULO,INST FIS & QUIM SAO CARLOS,BR-13560 SAO CARLOS,SP,BRAZIL. BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973. RP ZAGAL, J (reprint author), UNIV SANTIAGO CHILE,DEPT QUIM,CASILLA 5659,SANTIAGO 2,CHILE. RI PAEZ, MARITZA/F-1768-2011; zagal, jose/L-9648-2014; Paez, Maritza/M-2010-2014; Tanaka, Auro/G-5365-2016 OI Tanaka, Auro/0000-0003-4386-4071 NR 44 TC 168 Z9 169 U1 4 U2 64 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0022-0728 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD NOV 10 PY 1992 VL 339 IS 1-2 BP 13 EP 30 DI 10.1016/0022-0728(92)80442-7 PG 18 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA JZ188 UT WOS:A1992JZ18800003 ER PT J AU CAMERON, KL ROBINSON, JV NIEMEYER, S NIMZ, GJ KUENTZ, DC HARMON, RS BOHLEN, SR COLLERSON, KD AF CAMERON, KL ROBINSON, JV NIEMEYER, S NIMZ, GJ KUENTZ, DC HARMON, RS BOHLEN, SR COLLERSON, KD TI CONTRASTING STYLES OF PRE-CENOZOIC AND MIDTERTIARY CRUSTAL EVOLUTION IN NORTHERN MEXICO - EVIDENCE FROM DEEP CRUSTAL XENOLITHS FROM LA-OLIVINA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID RARE-EARTH ELEMENT; MIDTERTIARY FELSIC VOLCANICS; SR ISOTOPIC COMPOSITIONS; LOWER CONTINENTAL-CRUST; GARNET-ORTHOPYROXENE; SKAERGAARD INTRUSION; GEOCHEMICAL EVIDENCE; MAFIC XENOLITHS; MANTLE BOUNDARY; CENTRAL ARIZONA AB The principal deep crustal rock types found at the La Olivina xenolith locality in southeastern Chihuahua, Mexico, are mafic granulites, paragneisses, and intermediate- to silicic-composition orthogneisses. These granulite facies xenoliths are interpreted in terms of two age groups, pre-Cenozoic and mid-Tertiary, based on previous ion probe dating of zircons from the xenoliths and on isotopic comparisons of the xenoliths to rocks of known age. The mafic granulites have Pb, Nd, and Sr isotopic compositions identical to those of Oligocene volcanic rocks from the La Olivina region. Compositionally, they are olivine-normative gabbroic cumulates, and they precipitated from two or more mid-Tertiary basalt to dacite or rhyolite assimilation/fractional crystallization series. Mineral assemblages in the xenoliths record pressures of less-than-or-equal-to 7.2 kbar or depths of <25 km. If these are the maximum pressures the rocks experienced and if the crust was >35 km thick in Oligocene time as inferred from regional tectonic considerations, then the mafic granulites cannot be samples of basaltic magmas underplated near the crust-mantle boundary. The cumulate protoliths for the mafic granulites probably formed in magma chambers well above the Moho. The mafic granulites are plausibly representative of kilometers of new crust that formed in mid-Tertiary time beneath the extensive ignimbrite fields of Mexico. Most orthogneiss xenoliths are pre-Cenozoic, and they are rocks associated with the late Paleozoic Ouachita Orogeny and older events (e.g., Proterozoic basement and Paleozoic arc rocks). The Ouachita Orogeny was a collision event involving North America and a continental plate to the south, and the results of this study indicate that La Olivina is located above the southern plate. The paragneiss xenoliths overlap in isotopic composition with Carboniferous flysch units exposed in the Marathon uplift of west Texas. These sedimentary rocks and the sedimentary protoliths of the paragneiss xenoliths were derived from the southern plate and deposited before the orogeny in the ocean basin that separated North America and the southern plate. The paragneisses were not metamorphosed to granulite facies until mid-Tertiary time. Pre-Cenozoic and mid-Tertiary crustal evolution followed very different paths in northern Mexico. For example, Nd isotopic evidence for crustal recycling is much more evident in rocks associated with the Paleozoic convergence than in rocks produced during mid-Tertiary magmatism, Furthermore, mafic rocks are very rare in the pre-Cenozoic xenolith suite, but they dominate the mid-Tertiary one. These contrasting characteristics of the pre-Cenozoic and mid-Tertiary xenolith suites are interpreted to reflect differences in tectonic environment and crustal thickness. Preceding the collision event, the southern plate had an Andean-type margin, and the abundant evidence for crustal recycling during this time implies that the crust was thick. The rarity of pre-Cenozoic mafic xenoliths suggests that Proterozoic and Paleozoic lower crust may have delaminated in response to crustal overthickening associated with the Ouachita collision event. C1 NERC, ISOTOPE GEOSCI LAB, KEYWORTH NG12 5GG, ENGLAND. FUGRO MCCLELLAND W INC, SACRAMENTO, CA 95815 USA. US GEOL SURVEY, MENLO PK, CA 94025 USA. UNIV QUEENSLAND, DEPT EARTH SCI, ST LUCIA, QLD 4067, AUSTRALIA. LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RP CAMERON, KL (reprint author), UNIV CALIF SANTA CRUZ, BOARD EARTH SCI, SANTA CRUZ, CA 95064 USA. NR 95 TC 53 Z9 53 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD NOV 10 PY 1992 VL 97 IS B12 BP 17353 EP 17376 DI 10.1029/92JB01493 PG 24 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JY189 UT WOS:A1992JY18900009 ER PT J AU CARRIGAN, CR SCHUBERT, G EICHELBERGER, JC AF CARRIGAN, CR SCHUBERT, G EICHELBERGER, JC TI THERMAL AND DYNAMIC REGIMES OF SINGLE-PHASE AND 2-PHASE MAGMATIC FLOW IN DIKES SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID KILAUEA VOLCANO; HEAT-TRANSFER; BASALTIC MAGMA; RHEOLOGY; SYSTEMS; ASCENT; EMPLACEMENT; ERUPTIONS; VISCOSITY; CONDUITS AB Finite element calculations of magma flow in dikelike channels with length-to-width ratios of 1000:1 or more have been used to investigate the coupling between thermal and dynamical regimes due to temperature-dependent viscosity and dissipation. Steady state solutions with realistic thermal and dynamical parameter values have been obtained. The models show that the onset of solidification on the boundaries of a basaltic or andesitic dike, as predicted by idealized laminar flow models, can be prevented or significantly delayed by a small amount of transverse flow induced by rising bubbles, boundary roughness, or turbulence. This effect will reduce the critical initial widths of dikes estimated by Bruce and Huppert (1989). In the absence of transverse flow, the bulk temperature of the magma may actually increase slightly with distance along the dike as a result of viscous dissipation even while solidification is occurring on the walls of the dike. With converging or necking dike walls it is found that boundary temperatures fall to a minimum and then increase with distance along a dike even if viscous heating is neglected. For viscous heating to offset significant rates of heat loss (2 kW/m2) in a plane-parallel 1-m-wide basaltic dike, an average flow velocity of 2.7 m/s driven by a pressure gradient of 1.7 MPa/km is required. A 7% void fraction caused by exsolution of volatiles or chamber gas in the magma will produce this pressure gradient. The ease of producing such a gradient by reducing the density of the magmatic column with addition of a gas phase makes it likely that flows of basaltic magma could be maintained in dikes tens of kilometers long. Furthermore, a gas phase may be important for the propagation of the fracture prior to the initial injection of magma during dike emplacement. Rapid transport of more silicic magmas through dikes is inhibited by the requirement of large driving pressure gradients exceeding several hundred megapascals per kilometer. However, the pressure gradient can be substantially reduced if the magma is a heterogenous mixture of a predominantly silicic component with a more mafic component. Pipe flow experiments involving molten polymers that exhibit dynamical similarity to magmas strongly suggest that unmixing occurs when a two-component magma mixture, in which the components have different viscosities, rises within a dike. Within a few dike widths of the inlet the less viscous mafic component encapsulates the more viscous silicic part, effectively lubricating the passage of the more viscous component. Compositional variations in the Obsidian Dome volcano support the occurrence of this pressure reduction or self-lubrication mechanism. Such a self-lubrication process often may be necessary to permit very viscous magmas to reach Earth's surface. If so, chemical and lithologic zoning would be anticipated as a common feature of near-surface intrusions or lava flows that are characterized by a high silica and/or high crystal content such as at Deadman Dome in Long Valley, California. C1 UNIV ALASKA,INST GEOPHYS,FAIRBANKS,AK 99775. UNIV CALIF LOS ANGELES,INST GEOPHYS & PLANETARY PHYS,DEPT EARTH & SPACE SCI,LOS ANGELES,CA 90024. RP CARRIGAN, CR (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT EARTH SCI L206,LIVERMORE,CA 94550, USA. RI Eichelberger, John/H-6199-2016 NR 56 TC 57 Z9 59 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD NOV 10 PY 1992 VL 97 IS B12 BP 17377 EP 17392 DI 10.1029/92JB01244 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JY189 UT WOS:A1992JY18900010 ER PT J AU BERRYMAN, JG AF BERRYMAN, JG TI EFFECTIVE STRESS FOR TRANSPORT-PROPERTIES OF INHOMOGENEOUS POROUS ROCK SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID COMPLEX DIELECTRIC-CONSTANT; 2-COMPONENT COMPOSITE-MATERIAL; DYNAMIC ELASTIC PROPERTIES; EFFECTIVE PRESSURE LAW; CONFINING PRESSURE; PORE PRESSURE; RIGOROUS BOUNDS; BEREA SANDSTONE; ELECTRICAL-CONDUCTIVITY; PERMEABILITY AB General effective-stress rules are derived for various physical properties of inhomogeneous porous rocks. Some rigorous relations arising in the analysis show that the fluid (pore) pressure p(f) is least effective at counteracting the changes caused by confining pressure for the solid (grain) volume; p(f) is more effective for the total (solid plus pore) volume; p(f) is still more effective for the pore volume; and p(f) is most effective at maintaining the fluid content of the pores. Although these results are expected intuitively, this analysis provides the first rigorous demonstration. During analysis of coefficients, care is taken to distinguish between rigorous inequalities (following from thermodynamics) and empirical inequalities (commonly observed, but not required by thermodynamics). For microscopically homogeneous rocks (the Gassmann limit), it is shown that the confining pressure is always at least as effective as the fluid pressure at changing the fluid permeability; therefore it is impossible to use any "equivalent homogeneous rock" to explain experimental results of Zoback and Byerlee (1975) and others (wherein it has been shown experimentally that the permeability sometimes is more strongly influenced by fluid pressure than confining pressure). We show that the equivalent homogeneous rock paradigm may be successfully replaced by the "two-constituent porous medium" paradigm. In principle, the new paradigm can explain the data, but new measurements of pore compressibilities are required before quantitative comparisons can be made. RP LAWRENCE LIVERMORE NATL LAB, POB 808 L-202, LIVERMORE, CA 94550 USA. RI Berryman, James/A-9712-2008 NR 105 TC 125 Z9 137 U1 1 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD NOV 10 PY 1992 VL 97 IS B12 BP 17409 EP 17424 DI 10.1029/92JB01593 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JY189 UT WOS:A1992JY18900012 ER PT J AU BOERCKER, DB FALABELLA, S SANDERS, DM AF BOERCKER, DB FALABELLA, S SANDERS, DM TI PLASMA TRANSPORT IN A NEW CATHODIC ARC ION-SOURCE - THEORY AND EXPERIMENT SO SURFACE & COATINGS TECHNOLOGY LA English DT Article ID TECHNOLOGY AB We have developed a plasma transport code based upon the "flux tube" model and applied it to the ion transport in a recently developed metal-ion source based on the cathodic vacuum arc. This model is compared with ion current measurements made at various locations within the source. The agreement is sufficient to justify use of this model for future arc source design. RP BOERCKER, DB (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 10 TC 16 Z9 17 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV 10 PY 1992 VL 53 IS 3 BP 239 EP 242 DI 10.1016/0257-8972(92)90382-K PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA JW420 UT WOS:A1992JW42000005 ER PT J AU CAO, R YANG, X TERRY, J PIANETTA, P AF CAO, R YANG, X TERRY, J PIANETTA, P TI MICROSCOPIC STUDY OF THE SURFACTANT-ASSISTED SI, GE EPITAXIAL-GROWTH SO APPLIED PHYSICS LETTERS LA English DT Article ID STRAIN; PHOTOEMISSION; GE/SI(001); SB AB The Sb-assisted Si, Ge epitaxial growth processes have been studied using high resolution photoemission. It is found that the initially ordered Sb monolayer on the Si(100) and Ge(100) surfaces occupies the epitaxial sites and fully saturates the surface dangling bonds. This results in a reduction of the surface energy. During the growth process, the Sb atoms and the deposited Si, Ge atoms change their positions. Sb atoms segregate to the growth front to form a new ordered layer while leaving the uniform epitaxial Si, Ge layer behind. RP CAO, R (reprint author), STANFORD SYNCHROTRON RADIAT LAB,POB 4349,BIN 69,STANFORD,CA 94309, USA. NR 15 TC 35 Z9 36 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 9 PY 1992 VL 61 IS 19 BP 2347 EP 2349 DI 10.1063/1.108239 PG 3 WC Physics, Applied SC Physics GA JW880 UT WOS:A1992JW88000031 ER PT J AU KRISHNAN, KM AF KRISHNAN, KM TI FERROMAGNETIC DELTA-MN1-XGAX THIN-FILMS WITH PERPENDICULAR ANISOTROPY SO APPLIED PHYSICS LETTERS LA English DT Article AB We report the structure and properties of the thermodynamically stable delta-phase Mn1-xGax single crystal thin films grown on GaAs. X-ray THETA-2THETA scans and grazing-incidence scattering measurements confirmed that the unit cell of this phase is tetragonal (a = 0.279 nm, c = 0.351 nm) and grows with the c-axis oriented normal to the {001} GaAs substrate surface. X-ray emission spectroscopy confirmed the composition to be 62 +/- 2% Mn. Polar Kerr rotation, SQUID and vibrating sample magnetometer measurements with the field applied along the thin-film normal showed nearly perfect square hysteresis loops confirming perpendicular anisotropy of the films. The film exhibits a Kerr rotation angle of approximately 0.1-degrees at 820 nm, a coercivity of 6.27 kOe and a saturation magnetization of 460 emu/cm3. The optical reflectivity of the film was 65%-70% over a broad range of wavelengths. This unique set of properties make it a very promising material for magneto-optic recording with the additional potential of integrating semiconductor/magnetic devices by suitable patterning techniques. RP KRISHNAN, KM (reprint author), LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720, USA. NR 10 TC 92 Z9 92 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 9 PY 1992 VL 61 IS 19 BP 2365 EP 2367 DI 10.1063/1.108245 PG 3 WC Physics, Applied SC Physics GA JW880 UT WOS:A1992JW88000037 ER PT J AU HAGEN, M CHILD, HR FERNANDEZBACA, JA ZARESTKY, JL AF HAGEN, M CHILD, HR FERNANDEZBACA, JA ZARESTKY, JL TI A STUDY OF THE MAGNETIC CRITICAL SCATTERING FROM THE LONGITUDINALLY MODULATED ANTIFERROMAGNETS THULIUM AND ERBIUM SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID VECTOR MODELS; SPIN-WAVES; EXCITATIONS; METAL AB The temperature dependence of the magnetic critical scattering above T(N) and the staggered magnetization below T(N) has been measured in the longitudinally modulated antiferromagnets thulium and erbium using neutron diffraction. The transitions, which occur at T(N) = 57.65 +/- 0.10 K in thulium and at T(N) = 86.04 +/- 0.20 K in erbium appear to be continuous second-order transitions. As longitudinally modulated antiferromagnets thulium and erbium would be expected to belong to the d = 3, n = 2 universality class of the d = 3 XY-model. From an analysis of the critical scattering the exponents nu(c) = 0.43 +/- 0.02, nu(ab) = 0.40 +/- 0.02 and gamma = 0.90 +/- 0.04 have been deduced for thulium and nu(c) = 0.41 +/- 0.04, nu(ab) = 0.35 +/- 0.05 and gamma = 0.73 +/- 0.06 for erbium. These values are different to the theoretical values for the d = 3 XY-model of nu = 0.65 and gamma = 1.3. However, from the temperature dependence of the staggered magnetization the exponents beta = 0.37 +/- 0.03 for thulium and beta = 0.35 +/- 0.03 for erbium have been determined which are consistent with the theoretical value of beta = 0.35 for the d = 3 XY-model. It is speculated that the difference above T(N) between theory and experiment could arise if the exchange interaction were temperature dependent. C1 OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. RP HAGEN, M (reprint author), UNIV KEELE,DEPT PHYS,KEELE ST5 5BG,STAFFS,ENGLAND. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 10 TC 7 Z9 7 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 NOV 9 PY 1992 VL 4 IS 45 BP 8879 EP 8888 DI 10.1088/0953-8984/4/45/020 PG 10 WC Physics, Condensed Matter SC Physics GA JY109 UT WOS:A1992JY10900020 ER PT J AU KENT, MS BOSIO, L RONDELEZ, F AF KENT, MS BOSIO, L RONDELEZ, F TI HOMOPOLYMER ADSORPTION AT THE LIQUID AIR INTERFACE BY XEWIF SO MACROMOLECULES LA English DT Article ID ADSORBED POLYMER LAYERS; GOOD SOLVENT CONDITIONS; X-RAY-FLUORESCENCE; CONCENTRATION PROFILES; NEUTRON REFLECTIVITY; SURFACE-TENSION; THETA SOLVENT; POLYDIMETHYLSILOXANE; SCATTERING; VOLUME AB The adsorption of poly(dimethylsiloxane) to the air surface from solution in bromoheptane (good solvent) and bromocyclohexane (T(theta) = 29-degrees-C) has been studied by X-ray evanescent wave induced fluorescence (XEWIF). The sensitivity of the technique to the first approximately 40 angstrom of the surface region allows the determination of important qualitative features of the adsorbed concentration profiles. The effects of molecular weight, concentration, and solvent quality are examined in detail. In a good solvent, we find that the region of the profile nearest to the surface (approximately 40 angstrom) is roughly independent of molecular weight in dilute solution, in agreement with theoretical predictions. Additional information about the adsorbed profile is obtained by varying the bulk polymer concentration. From these data we infer a profile with a high surface concentration (approximately 90 +/- 10%) which decays to under 20% within the first approximately 20 angstrom in the dilute and semidilute regimes. For near-theta conditions, we find the adsorbed amount in dilute solution to be approximately 4 times larger than in a good solvent, with the profile decaying much more slowly with depth than in the good solvent. In addition, there appears to be a higher dependence on molecular weight for the region of the profile within approximately 40 angstrom of the surface. The results in good and near-theta conditions are well described by both mean-field and scaling theories, while, on the contrary, the profile becomes qualitatively different in the proximity of the bulk coexistence curve (i.e., T < T(c)). C1 SANDIA NATL LABS,DIV 1815,ALBUQUERQUE,NM 87185. ECOLE SUPER PHYS & CHIM IND,PHYS LIQUIDES & ELECTROCHIM LAB,F-75005 PARIS,FRANCE. RP KENT, MS (reprint author), UNIV PARIS 06,INST CURIE,CNRS,URA 1379,PHYSICOCHIM SURFACES & INTERFACES LAB,F-75005 PARIS,FRANCE. NR 26 TC 11 Z9 11 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD NOV 9 PY 1992 VL 25 IS 23 BP 6231 EP 6239 DI 10.1021/ma00049a020 PG 9 WC Polymer Science SC Polymer Science GA JX890 UT WOS:A1992JX89000020 ER PT J AU KENT, MS LEE, LT FARNOUX, B RONDELEZ, F AF KENT, MS LEE, LT FARNOUX, B RONDELEZ, F TI CHARACTERIZATION OF DIBLOCK COPOLYMER MONOLAYERS AT THE LIQUID AIR INTERFACE BY NEUTRON REFLECTIVITY AND SURFACE-TENSION MEASUREMENTS SO MACROMOLECULES LA English DT Article ID TERMINALLY ATTACHED CHAINS; ANCHORED POLYMER-CHAINS; CONSISTENT FIELD-THEORY; BLOCK COPOLYMERS; ADSORBED POLYMERS; DENSITY PROFILE; MOLECULAR-DYNAMICS; GRAFTED POLYMERS; GOOD SOLVENT; MONTE-CARLO AB We report simultaneous measurements of the concentration profile and the free energy of the submerged PS blocks of PDMS-PS diblock copolymers spread as monolayers at the air surface of ethyl benzoate as a function of surface concentration. A parabolic concentration profile is found to give the best fit to neutron reflectivity curves among the set of two-parameter models examined. The maximum extension h*/R(g) is comparable to previously reported values obtained from a variety of techniques for similar values of the reduced surface density sigma* and indicates some stretching perpendicular to the surface. As sigma* increases from 1.3 to 4.2, the energy per PS block (obtained from surface tension measurements) increases sharply while the dependence of h* on sigma* is much weaker than the 1/3 power law dependence predicted for the strongly stretched regime. Thus, the energy required to stretch the chains for this system appears to be much larger than predicted by current theories. C1 SANDIA NATL LABS,DIV 1815,ALBUQUERQUE,NM 87185. CENS,CNRS,CEA,LAB LEON BRILLOUIN,F-91191 GIF SUR YVETTE,FRANCE. RP KENT, MS (reprint author), UNIV PARIS 06,INST CURIE,CNRS,URA 1379,PHYSICOCHIM SURFACES & INTERFACES LAB,F-75005 PARIS,FRANCE. NR 42 TC 95 Z9 95 U1 2 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD NOV 9 PY 1992 VL 25 IS 23 BP 6240 EP 6247 DI 10.1021/ma00049a021 PG 8 WC Polymer Science SC Polymer Science GA JX890 UT WOS:A1992JX89000021 ER PT J AU NARDI, E ROULET, E TOMMASINI, D AF NARDI, E ROULET, E TOMMASINI, D TI GLOBAL ANALYSIS OF FERMION MIXING WITH EXOTICS SO NUCLEAR PHYSICS B LA English DT Article ID HEAVY FLAVOR PRODUCTION; HADRONIC Z0 DECAYS; ELECTROWEAK RADIATIVE-CORRECTIONS; BRANCHING RATIO BR(B->L+X); FORWARD-BACKWARD ASYMMETRY; ATOMIC PARITY VIOLATION; OPPOSITE-SIGN DIMUONS; STANDARD MODEL; E+E ANNIHILATION; NEUTRAL-CURRENT AB We analyze the limits on deviations of the lepton and quark weak-couplings from their standard model values in a general class of models where the known fermions are allowed to mix with new heavy particles with exotic SU(2) x U(1) quantum number assignments (left-handed singlets or right-handed doublets). These mixings appear in many extensions of the electroweak theory such as models with mirror fermions, E6 models, etc. Our results update previous analyses and improve considerably the existing bounds. As experimental constraints we use the new results on M(Z), GAMMA(Z), on the Z partial decay-widths and on the asymmetries measured at the Z-resonance, as well as updated results on the W-mass, on deep-inelastic nu-q and nu-e scattering and on atomic parity violation. Present constraints on lepton universality, unitarity of the quark mixing matrix and induced right-handed currents are also included. A global analysis of all these data leads to upper limits on the mixing factors s2 = sin2theta(mix). When just one mixing is constrained at a time, we obtain for most of the fermions the tight limits s2 less than or similar to 0.002 divided-by 0.01 at 90% C.L. For u(R), c(R) and nu(tau) the bounds are s2 < 0.03, however if nu(tau) mixes with an ordinary heavy neutrino the constraint is s2 < 0.1 and a signal of non-zero mixing at 90% C.L. is found. For s(R) and b(R) we find the much weaker bounds s2 less than or similar to 0.35. The constraints are weakened by a factor between 2 and 5 if accidental cancellations among different mixings are allowed to occur. C1 SCUOLA INT SUPER STUDI AVANZATI,I-34014 TRIESTE,ITALY. IST NAZL FIS NUCL,TRIESTE,ITALY. NASA,FERMILAB ASTROPHYS CTR,FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. RP NARDI, E (reprint author), UNIV MICHIGAN,RANDALL LAB PHYS,ANN ARBOR,MI 48109, USA. RI Tommasini, Daniele/L-4718-2014; OI Tommasini, Daniele/0000-0002-7997-3088; Nardi, Enrico/0000-0001-7165-3808 NR 125 TC 76 Z9 76 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 NOV 9 PY 1992 VL 386 IS 2 BP 239 EP 266 DI 10.1016/0550-3213(92)90566-T PG 28 WC Physics, Particles & Fields SC Physics GA KC702 UT WOS:A1992KC70200001 ER PT J AU ABREU, P ADAM, W ADYE, T AGASI, E ALEKSEEV, GD ALGERI, A ALLEN, P ALMEHED, S ALVSVAAG, SJ AMALDI, U ANASSONTZIS, EG ANDREAZZA, A ANTILOGUS, P APEL, WD APSIMON, RJ ASMAN, B AUGUSTIN, JE AUGUSTINUS, A BAILLON, P BAMBADE, P BARAO, F BARATE, R BARBIELLINI, G BARDIN, DY BARKER, G BARONCELLI, A BARRING, O BARRIO, JA BARTL, W BATES, MJ BATTAGLIA, M BAUBILLIER, M BECKS, KH BEESTON, CJ BEGALLI, M BEILLIERE, P BELOKOPYTOV, Y BELTRAN, P BENEDIC, D BENVENUTI, AC BERGGREN, M BERTRAND, D BIANCHI, F BILENKY, MS BILLOIR, P BJARNE, J BLOCH, D BLYTH, S BOCCI, V BOGOLUBOV, PN BOLOGNESE, T BONESINI, M BONIVENTO, W BOOTH, PSL BORGEAUD, P BORISOV, G BORNER, H BOSIO, C BOSTJANCIC, B BOSWORTH, S BOTNER, O BOUQUET, B BOURDARIOS, C BOWCOCK, TJV BOZZO, M BRAIBANT, S BRANCHINI, P BRAND, KD BRENNER, RA BRIAND, H BRICMAN, C BROWN, RCA BRUMMER, N BRUNET, JM BUGGE, L BURAN, T BURMEISTER, H BUYTAERT, JAMA CACCIA, M CALVI, M ROZAS, AJC CAMPORESI, T CANALE, V CAO, F CARENA, F CARROLL, L CASO, C GIMENEZ, MVC CATTAI, A CAVALLO, FR CERRITO, L CHABAUD, V CHAN, A CHARPENTIER, P CHAUSSARD, L CHAUVEAU, J CHECCHIA, P CHELKOV, GA CHEVALIER, L CHLIAPNIKOV, P CHOROWICZ, V CHRIN, JTM CLARA, MP COLLINS, P CONTRERAS, JL CONTRI, R CORTINA, E COSME, G COUCHOT, F CRAWLEY, HB CRENNELL, D CROSETTI, G CROZON, M MAESTRO, JC CZELLAR, S DAHLJENSEN, E DALMAGNE, B DAM, M DAMGAARD, G DARBO, G DAUBIE, E DAUM, A DAUNCEY, PD DAVENPORT, M DAVID, P DASILVA, W DEFOIX, C DELIKARIS, D DELORME, S DELPIERRE, P DEMARIA, N DEANGELIS, A DEBEER, M DEBOECK, H DEBOER, W DECLERCQ, C LASO, MDMD DEGROOT, N DELAVAISSIERE, C DELOTTO, B DEMIN, A DIJKSTRA, H DICIACCIO, L DJAMA, F DOLBEAU, J DONSZELMANN, M DOROBA, K DRACOS, M DREES, J DRIS, M DUFOUR, Y EEK, LO EEROLA, PAM EHRET, R EKELOF, T EKSPONG, G PEISERT, AE ENGEL, JP FASSOULIOTIS, D FEARNLEY, TA FEINDT, M ALONSO, MF FERRER, A FILIPPAS, TA FIRESTONE, A FOETH, H FOKITIS, E FONTANELLI, F FORBES, KAJ FOUSSET, JL FRANCON, S FRANEK, B FRENKIEL, P FRIES, DC FRODESEN, AG FRUHWIRTH, R FULDAQUENZER, F FURNIVAL, K FURSTENAU, H FUSTER, J GALEAZZI, G GAMBA, D GARCIA, C GARCIA, J GASPAR, C GASPARINI, U GAVILLET, P GAZIS, EN GERBER, JP GIACOMELLI, P GOKIELI, R GOLOB, B GOLOVATYUK, VM CADENAS, JJGY GOOBAR, A GOPAL, G GORSKI, M GRACCO, V GRANT, A GRARD, F GRAZIANI, E GROSDIDIER, G GROSS, E GROSSEWIESMANN, P GROSSETETE, B GUY, J HAEDINGER, U HAHN, F HAHN, M HAIDER, S HAJDUK, Z HAKANSSON, A HALLGREN, A HAMACHER, K DEMONCHENAULT, GH HAO, W HARRIS, FJ HENKES, T HERNANDEZ, JJ HERQUET, P HERR, H HESSING, TL HIETANEN, I HIGGINS, CO HIGON, E HILKE, HJ HODGSON, SD HOFMOKL, T HOLMES, R HOLMGREN, SO HOLTHUIZEN, D HONORE, PF HOOPER, JE HOULDEN, M HRUBEC, J HUET, C HULTH, PO HULTQVIST, K IOANNOU, P ISENHOWER, D IVERSEN, PS JACKSON, JN JALOCHA, P JARLSKOG, G JARRY, P JEANMARIE, B JOHANSSON, EK JOHNSON, D JONKER, M JONSSON, L JUILLOT, P KALKANIS, G KALMUS, G KAPUSTA, F KARLSSON, M KARVELAS, E KATSANEVAS, S KATSOUFIS, EC KERANEN, R KESTEMAN, J KHOMENKO, BA KHOVANSKI, NN KING, B KJAER, NJ KLEIN, H KLEMPT, W KLOVNING, A KLUIT, P KOCHMEHRIN, A KOEHNE, JH KOENE, B KOKKINIAS, P KOPF, M KORCYL, K KORYTOV, AV KOSTIOUKHINE, V KOURKOUMELIS, C KOUZNETSOV, O KRAMER, PH KROLIKOWSKI, J KRONKVIST, I KRUENERMARQUIS, U KRUPINSKI, W KULKA, K KURVINEN, K LACASTA, C LAMBROPOULOS, C LAMSA, JW LANCERI, L LAPIN, V LAUGIER, JP LAUHAKANGAS, R LEDER, G LEDROIT, F LEITNER, R LEMOIGNE, Y LEMONNE, J LENZEN, G LEPELTIER, V LEVY, JM LIEB, E LIKO, D LILLETHUN, E LINDGREN, J LINDNER, R LIPNIACKA, A LIPPI, I LOERSTAD, B LOKAJICEK, M LOKEN, JG LOPEZFERNANDEZ, A AGUERA, MAL LOS, M LOUKAS, D LOZANO, JJ LUTZ, P LYONS, L MAEHLUM, G MAILLARD, J MALTEZOS, A MANDL, F MARCO, J MARGONI, M MARIN, JC MARKOU, A MARON, T MARTI, S MATHIS, L MATORRAS, F MATTEUZZI, C MATTHIAE, G MAZZUCATO, M MCCUBBIN, M MCKAY, R MCNULTY, R MEOLA, G MERONI, C MEYER, WT MICHELOTTO, M MIKULEC, I MIRABITO, L MITAROFF, WA MITSELMAKHER, GV MJOERNMARK, U MOA, T MOELLER, R MOENIG, K MONGE, MR MORETTINI, P MUELLER, H MURRAY, WJ MURYN, B MYATT, G NARAGHI, F NAVARRIA, FL NEGRI, P NIELSEN, BS NIJJHAR, B NIKOLAENKO, V NILSEN, PES NISS, P OBRAZTSOV, V OLSHEVSKI, AG ORAVA, R OSTANKOV, A OSTERBERG, K OURAOU, A PAGANONI, M PAIN, R PALKA, H PAPADOPOULOU, TD PAPE, L PASSERI, A PEGORARO, M PENNANEN, J PEREVOZCHIKOV, V PERNICKA, M PERROTTA, A PETRIDOU, C PETROLINI, A PETTERSEN, TE PIERRE, F PIMENTA, M PINGOT, O POL, ME POLOK, G POROPAT, P PRIVITERA, P PULLIA, A RADOJICIC, D RAGAZZI, S RAHMANI, H RATOFF, PN READ, AL REDAELLI, NG REGLER, M REID, D RENTON, PB RESVANIS, LK RICHARD, F RICHARDSON, M RIDKY, J RINAUDO, G RODITI, I ROMERO, A RONCAGLIOLO, I RONCHESE, P RONNQVIST, C ROSENBERG, EI ROSSI, S ROSSI, U ROSSO, E ROUDEAU, P ROVELLI, T RUCKSTUHL, W RUHLMANNKLEIDER, V RUIZ, A RYBICKI, K SAARIKKO, H SACQUIN, Y SAJOT, G SALT, J SANCHEZ, J SANNINO, M SCHAEL, S SCHNEIDER, H SCHYNS, MAE SCIOLLA, G SCURI, F SEGAR, AM SEKULIN, R SESSA, M SETTE, G SEUFERT, R SHELLARD, RC SICCAMA, I SIEGRIST, P SIMONETTI, S SIMONETTO, F SISAKIAN, AN SKAALI, TB SKJEVLING, G SMADJA, G SMITH, GR SOSNOWSKI, R SPASSOFF, TS SPIRITI, E SQUARCIA, S STAECK, H STANESCU, C STAPNES, S STAVROPOULOS, G STICHELBAUT, F STOCCHI, A STRAUSS, J STRAVER, J STRUB, R SZCZEKOWSKI, M SZEPTYCKA, M SZYMANSKI, P TABARELLI, T TAVERNIER, S TCHIKILEV, O THEODOSIOU, GE TILQUIN, A TIMMERMANS, J TIMOFEEV, VG TKATCHEV, LG TODOROV, T TOET, DZ TOKER, O TORASSA, E TORTORA, L TREILLE, D TREVISAN, U TRISCHUK, W TRISTRAM, G TRONCON, C TSIROU, A TSYGANOV, EN TURALA, M TURLUER, ML TUUVA, T TYAPKIN, IA TYNDEL, M TZAMARIAS, S UEBERSCHAER, S ULLALAND, O UVAROV, V VALENTI, G VALLAZZA, E FERRER, JAV VANDERVELDE, C VANAPELDOORN, GW VANDAM, P VANDERHEIJDEN, M VANDONINCK, WK VAZ, P VEGNI, G VENTURA, L VENUS, W VERBEURE, F VERTOGRADOV, LS VILANOVA, D VINCENT, P VITALE, L VLASOV, E VODOPYANOV, AS VOLLMER, M VOULGARIS, G VOUTILAINEN, M VRBA, V WAHLEN, H WALCK, C WALDNER, F WAYNE, M WEHR, A WEIERSTALL, M WEILHAMMER, P WERNER, J WETHERELL, AM WICKENS, JH WIKNE, J WILKINSON, GR WILLIAMS, WSC WINTER, M WORMALD, D WORMSER, G WOSCHNAGG, K YAMDAGNI, N YEPES, P ZAITSEV, A ZALEWSKA, A ZALEWSKI, P ZAVRTANIK, D ZEVGOLATAKOS, E ZHANG, G ZIMIN, NI ZITO, M ZUBERI, R FUNCHAL, RZ ZUMERLE, G ZUNIGA, J AF ABREU, P ADAM, W ADYE, T AGASI, E ALEKSEEV, GD ALGERI, A ALLEN, P ALMEHED, S ALVSVAAG, SJ AMALDI, U ANASSONTZIS, EG ANDREAZZA, A ANTILOGUS, P APEL, WD APSIMON, RJ ASMAN, B AUGUSTIN, JE AUGUSTINUS, A BAILLON, P BAMBADE, P BARAO, F BARATE, R BARBIELLINI, G BARDIN, DY BARKER, G BARONCELLI, A BARRING, O BARRIO, JA BARTL, W BATES, MJ BATTAGLIA, M BAUBILLIER, M BECKS, KH BEESTON, CJ BEGALLI, M BEILLIERE, P BELOKOPYTOV, Y BELTRAN, P BENEDIC, D BENVENUTI, AC BERGGREN, M BERTRAND, D BIANCHI, F BILENKY, MS BILLOIR, P BJARNE, J BLOCH, D BLYTH, S BOCCI, V BOGOLUBOV, PN BOLOGNESE, T BONESINI, M BONIVENTO, W BOOTH, PSL BORGEAUD, P BORISOV, G BORNER, H BOSIO, C BOSTJANCIC, B BOSWORTH, S BOTNER, O BOUQUET, B BOURDARIOS, C BOWCOCK, TJV BOZZO, M BRAIBANT, S BRANCHINI, P BRAND, KD BRENNER, RA BRIAND, H BRICMAN, C BROWN, RCA BRUMMER, N BRUNET, JM BUGGE, L BURAN, T BURMEISTER, H BUYTAERT, JAMA CACCIA, M CALVI, M ROZAS, AJC CAMPORESI, T CANALE, V CAO, F CARENA, F CARROLL, L CASO, C GIMENEZ, MVC CATTAI, A CAVALLO, FR CERRITO, L CHABAUD, V CHAN, A CHARPENTIER, P CHAUSSARD, L CHAUVEAU, J CHECCHIA, P CHELKOV, GA CHEVALIER, L CHLIAPNIKOV, P CHOROWICZ, V CHRIN, JTM CLARA, MP COLLINS, P CONTRERAS, JL CONTRI, R CORTINA, E COSME, G COUCHOT, F CRAWLEY, HB CRENNELL, D CROSETTI, G CROZON, M MAESTRO, JC CZELLAR, S DAHLJENSEN, E DALMAGNE, B DAM, M DAMGAARD, G DARBO, G DAUBIE, E DAUM, A DAUNCEY, PD DAVENPORT, M DAVID, P DASILVA, W DEFOIX, C DELIKARIS, D DELORME, S DELPIERRE, P DEMARIA, N DEANGELIS, A DEBEER, M DEBOECK, H DEBOER, W DECLERCQ, C LASO, MDMD DEGROOT, N DELAVAISSIERE, C DELOTTO, B DEMIN, A DIJKSTRA, H DICIACCIO, L DJAMA, F DOLBEAU, J DONSZELMANN, M DOROBA, K DRACOS, M DREES, J DRIS, M DUFOUR, Y EEK, LO EEROLA, PAM EHRET, R EKELOF, T EKSPONG, G PEISERT, AE ENGEL, JP FASSOULIOTIS, D FEARNLEY, TA FEINDT, M ALONSO, MF FERRER, A FILIPPAS, TA FIRESTONE, A FOETH, H FOKITIS, E FONTANELLI, F FORBES, KAJ FOUSSET, JL FRANCON, S FRANEK, B FRENKIEL, P FRIES, DC FRODESEN, AG FRUHWIRTH, R FULDAQUENZER, F FURNIVAL, K FURSTENAU, H FUSTER, J GALEAZZI, G GAMBA, D GARCIA, C GARCIA, J GASPAR, C GASPARINI, U GAVILLET, P GAZIS, EN GERBER, JP GIACOMELLI, P GOKIELI, R GOLOB, B GOLOVATYUK, VM CADENAS, JJGY GOOBAR, A GOPAL, G GORSKI, M GRACCO, V GRANT, A GRARD, F GRAZIANI, E GROSDIDIER, G GROSS, E GROSSEWIESMANN, P GROSSETETE, B GUY, J HAEDINGER, U HAHN, F HAHN, M HAIDER, S HAJDUK, Z HAKANSSON, A HALLGREN, A HAMACHER, K DEMONCHENAULT, GH HAO, W HARRIS, FJ HENKES, T HERNANDEZ, JJ HERQUET, P HERR, H HESSING, TL HIETANEN, I HIGGINS, CO HIGON, E HILKE, HJ HODGSON, SD HOFMOKL, T HOLMES, R HOLMGREN, SO HOLTHUIZEN, D HONORE, PF HOOPER, JE HOULDEN, M HRUBEC, J HUET, C HULTH, PO HULTQVIST, K IOANNOU, P ISENHOWER, D IVERSEN, PS JACKSON, JN JALOCHA, P JARLSKOG, G JARRY, P JEANMARIE, B JOHANSSON, EK JOHNSON, D JONKER, M JONSSON, L JUILLOT, P KALKANIS, G KALMUS, G KAPUSTA, F KARLSSON, M KARVELAS, E KATSANEVAS, S KATSOUFIS, EC KERANEN, R KESTEMAN, J KHOMENKO, BA KHOVANSKI, NN KING, B KJAER, NJ KLEIN, H KLEMPT, W KLOVNING, A KLUIT, P KOCHMEHRIN, A KOEHNE, JH KOENE, B KOKKINIAS, P KOPF, M KORCYL, K KORYTOV, AV KOSTIOUKHINE, V KOURKOUMELIS, C KOUZNETSOV, O KRAMER, PH KROLIKOWSKI, J KRONKVIST, I KRUENERMARQUIS, U KRUPINSKI, W KULKA, K KURVINEN, K LACASTA, C LAMBROPOULOS, C LAMSA, JW LANCERI, L LAPIN, V LAUGIER, JP LAUHAKANGAS, R LEDER, G LEDROIT, F LEITNER, R LEMOIGNE, Y LEMONNE, J LENZEN, G LEPELTIER, V LEVY, JM LIEB, E LIKO, D LILLETHUN, E LINDGREN, J LINDNER, R LIPNIACKA, A LIPPI, I LOERSTAD, B LOKAJICEK, M LOKEN, JG LOPEZFERNANDEZ, A AGUERA, MAL LOS, M LOUKAS, D LOZANO, JJ LUTZ, P LYONS, L MAEHLUM, G MAILLARD, J MALTEZOS, A MANDL, F MARCO, J MARGONI, M MARIN, JC MARKOU, A MARON, T MARTI, S MATHIS, L MATORRAS, F MATTEUZZI, C MATTHIAE, G MAZZUCATO, M MCCUBBIN, M MCKAY, R MCNULTY, R MEOLA, G MERONI, C MEYER, WT MICHELOTTO, M MIKULEC, I MIRABITO, L MITAROFF, WA MITSELMAKHER, GV MJOERNMARK, U MOA, T MOELLER, R MOENIG, K MONGE, MR MORETTINI, P MUELLER, H MURRAY, WJ MURYN, B MYATT, G NARAGHI, F NAVARRIA, FL NEGRI, P NIELSEN, BS NIJJHAR, B NIKOLAENKO, V NILSEN, PES NISS, P OBRAZTSOV, V OLSHEVSKI, AG ORAVA, R OSTANKOV, A OSTERBERG, K OURAOU, A PAGANONI, M PAIN, R PALKA, H PAPADOPOULOU, TD PAPE, L PASSERI, A PEGORARO, M PENNANEN, J PEREVOZCHIKOV, V PERNICKA, M PERROTTA, A PETRIDOU, C PETROLINI, A PETTERSEN, TE PIERRE, F PIMENTA, M PINGOT, O POL, ME POLOK, G POROPAT, P PRIVITERA, P PULLIA, A RADOJICIC, D RAGAZZI, S RAHMANI, H RATOFF, PN READ, AL REDAELLI, NG REGLER, M REID, D RENTON, PB RESVANIS, LK RICHARD, F RICHARDSON, M RIDKY, J RINAUDO, G RODITI, I ROMERO, A RONCAGLIOLO, I RONCHESE, P RONNQVIST, C ROSENBERG, EI ROSSI, S ROSSI, U ROSSO, E ROUDEAU, P ROVELLI, T RUCKSTUHL, W RUHLMANNKLEIDER, V RUIZ, A RYBICKI, K SAARIKKO, H SACQUIN, Y SAJOT, G SALT, J SANCHEZ, J SANNINO, M SCHAEL, S SCHNEIDER, H SCHYNS, MAE SCIOLLA, G SCURI, F SEGAR, AM SEKULIN, R SESSA, M SETTE, G SEUFERT, R SHELLARD, RC SICCAMA, I SIEGRIST, P SIMONETTI, S SIMONETTO, F SISAKIAN, AN SKAALI, TB SKJEVLING, G SMADJA, G SMITH, GR SOSNOWSKI, R SPASSOFF, TS SPIRITI, E SQUARCIA, S STAECK, H STANESCU, C STAPNES, S STAVROPOULOS, G STICHELBAUT, F STOCCHI, A STRAUSS, J STRAVER, J STRUB, R SZCZEKOWSKI, M SZEPTYCKA, M SZYMANSKI, P TABARELLI, T TAVERNIER, S TCHIKILEV, O THEODOSIOU, GE TILQUIN, A TIMMERMANS, J TIMOFEEV, VG TKATCHEV, LG TODOROV, T TOET, DZ TOKER, O TORASSA, E TORTORA, L TREILLE, D TREVISAN, U TRISCHUK, W TRISTRAM, G TRONCON, C TSIROU, A TSYGANOV, EN TURALA, M TURLUER, ML TUUVA, T TYAPKIN, IA TYNDEL, M TZAMARIAS, S UEBERSCHAER, S ULLALAND, O UVAROV, V VALENTI, G VALLAZZA, E FERRER, JAV VANDERVELDE, C VANAPELDOORN, GW VANDAM, P VANDERHEIJDEN, M VANDONINCK, WK VAZ, P VEGNI, G VENTURA, L VENUS, W VERBEURE, F VERTOGRADOV, LS VILANOVA, D VINCENT, P VITALE, L VLASOV, E VODOPYANOV, AS VOLLMER, M VOULGARIS, G VOUTILAINEN, M VRBA, V WAHLEN, H WALCK, C WALDNER, F WAYNE, M WEHR, A WEIERSTALL, M WEILHAMMER, P WERNER, J WETHERELL, AM WICKENS, JH WIKNE, J WILKINSON, GR WILLIAMS, WSC WINTER, M WORMALD, D WORMSER, G WOSCHNAGG, K YAMDAGNI, N YEPES, P ZAITSEV, A ZALEWSKA, A ZALEWSKI, P ZAVRTANIK, D ZEVGOLATAKOS, E ZHANG, G ZIMIN, NI ZITO, M ZUBERI, R FUNCHAL, RZ ZUMERLE, G ZUNIGA, J TI MULTIPLICITY FLUCTUATIONS IN HADRONIC FINAL-STATES FROM THE DECAY OF THE Z(0) SO NUCLEAR PHYSICS B LA English DT Article ID LUND MONTE-CARLO; HIGH-ENERGY COLLISIONS; E+E ANNIHILATION; MULTIPARTICLE PRODUCTION; RAPIDITY DISTRIBUTIONS; INTERMITTENCY ANALYSIS; JET FRAGMENTATION; Z0; QCD; SIMULATION AB An analysis of the fluctuations in the phase space distribution of hadrons produced in the decay of 78829 Z0 has been carried out, using the method of factorial moments. The high statistics collected by the DELPHI experiment at LEP during 1990 allowed studies of the event sample both globally and in intervals of p(t) and multiplicity, and for different jet topologies and for single jets. A large contribution to the factorial moments of the one-dimensional data on rapidity with respect to the event axis comes from hard gluons. Details of factorial moments in two and three dimensions are presented. Influences of resonance decays have been studied by Monte Carlo simulation: one-dimensional factorial moments at low p(t), and two-, three-dimensional analyses are affected. Parton shower models describe the data reasonably well. C1 NCSR DEMOKRITOS,INST NUCL PHYS,GR-15310 ATHENS,GREECE. ULP,CTR RECH NUCL,IN2P3,F-67037 STRASBOURG,FRANCE. INFN,I-40126 BOLOGNA,ITALY. UNIV BOLOGNA,DIPARTIMENTO FIS,I-40126 BOLOGNA,ITALY. VUB,ULB,B-1050 BRUSSELS,BELGIUM. UNIV ETAT MONS,FAC MED,B-7000 MONS,BELGIUM. UNIV INSTELLING ANTWERP,DEPT PHYS,B-2610 WILRIJK,BELGIUM. UNIV TURIN,DIPARTIMENTO FIS SPERIMENTALE,I-10125 TURIN,ITALY. INFN,I-10125 TURIN,ITALY. UNIV ROME 2,DIPARTIMENTO FIS,I-00173 ROME,ITALY. INFN,I-00173 ROME,ITALY. CENS,DSM,DAPNIA,F-91191 GIF SUR YVETTE,FRANCE. UNIV LIVERPOOL,DEPT PHYS,LIVERPOOL L69 3BX,ENGLAND. UNIV UPPSALA,DEPT RADIAT SCI,S-75121 UPPSALA,SWEDEN. UNIV GENOA,DIPARTIMENTO FIS,I-16146 GENOA,ITALY. INFN,I-16146 GENOA,ITALY. UNIV PADUA,DIPARTIMENTO FIS,I-35131 PADUA,ITALY. INFN,I-35131 PADUA,ITALY. UNIV OSLO,DEPT PHYS,N-1000 OSLO 3,NORWAY. UNIV SANTANDER,FAC CIENCIAS,E-39005 SANTANDER,SPAIN. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. NIELS BOHR INST,DK-2100 COPENHAGEN 0,DENMARK. INST NUCLEAR STUDIES,PL-00681 WARSAW,POLAND. UNIV WARSAW,PL-00681 WARSAW,POLAND. NATL TECH UNIV ATHENS,DEPT PHYS,GR-15773 ATHENS,GREECE. UNIV MARSEILLE 2,F-13288 MARSEILLE 09,FRANCE. INST JOZEF STEFAN,LJUBLJANA,YUGOSLAVIA. INST NUCL PHYS,HIGH ENERGY PHYS LAB,PL-30055 KRAKOW 30,POLAND. UNIV LANCASTER,SCH PHYS & MAT,LANCASTER LA1 4YB,ENGLAND. CTR BRASILEIRO PESQUISAS FIS,BR-22290 RIO JANEIRO,BRAZIL. AUSTRIAN ACAD SCI,INST HOCHENERGIEPHYS,A-1050 VIENNA,AUSTRIA. RUTHERFORD APPLETON LAB,DIDCOT OX11 0QX,OXON,ENGLAND. NIKHEI-H,1009 DB AMSTERDAM,NETHERLANDS. JOINT INST NUCL RES,101000 MOSCOW,USSR. RES INST HIGH ENERGY PHYS,SEFT,SF-00170 HELSINKI,FINLAND. CSIC,IFIC,VALENCIA,SPAIN. UNIV VALENCIA,DFAMN,E-46100 BURJASSOT,SPAIN. UNIV LUND,DEPT PHYS,S-22363 LUND,SWEDEN. UNIV BERGEN,DEPT PHYS,N-5007 BERGEN,NORWAY. CERN,CH-1211 GENEVA 23,SWITZERLAND. UNIV ATHENS,PHYS LAB,GR-10680 ATHENS,GREECE. UNIV MILAN,DIPARTIMENTO FIS,I-20133 MILAN,ITALY. INFN,I-20133 MILAN,ITALY. UNIV LYON 1,F-69622 VILLEURBANNE,FRANCE. UNIV KARLSRUHE,INST EXPTL KERNPHYS,W-7500 KARLSRUHE 1,GERMANY. UNIV STOCKHOLM,INST PHYS,S-11346 STOCKHOLM,SWEDEN. UNIV PARIS 11,ACCELERATEUR LINEAIRE LAB,F-91405 ORSAY,FRANCE. UNIV GRENOBLE 1,INST SCI NUCL,F-38026 GRENOBLE,FRANCE. UNIV TRIESTE,DIPARTIMENTO FIS,I-34127 TRIESTE,ITALY. INFN,I-34127 TRIESTE,ITALY. UNIV UDINE,IST FIS,I-33100 UDINE,ITALY. UNIV OXFORD,NUCL PHYS LAB,OXFORD OX1 3RH,ENGLAND. IST NAZL FIS NUCL,IST SUPER SANITA,I-00161 ROME,ITALY. UNIV COMPLUTENSE,E-28040 MADRID,SPAIN. UNIV PARIS 06,LPNHE,F-75230 PARIS 05,FRANCE. UNIV PARIS 07,F-75230 PARIS 05,FRANCE. UNIV GESAMTHSCH WUPPERTAL,FACHBEREICH PHYS,W-5600 WUPPERTAL 1,GERMANY. PONTIFICA UNIV CATOLICA,DEPT PHYS,BR-22453 RIO JANEIRO,BRAZIL. COLL FRANCE,PHYS CORPUSCULAIRE LAB,F-75231 PARIS 05,FRANCE. SERPUKHOV HIGH ENERGY PHYS INST,SERPUKHOV,USSR. RP ABREU, P (reprint author), FOUL,IST,LIP,AV ELIAS GARCIA 14 1E,P-1000 LISBON,PORTUGAL. RI Zaitsev, Alexandre/B-8989-2017; Michelotto, Michele/A-9571-2013; Matorras, Francisco/I-4983-2015; Ferrer, Antonio/H-2942-2015; Rovelli, Tiziano/K-4432-2015; Fernandez-Alonso, Mercedes/F-2557-2016; Lozano-Bahilo, Julio/F-4881-2016; Olshevskiy, Alexander/I-1580-2016; Paganoni, Marco/A-4235-2016; Contreras Gonzalez, Jose Luis/K-7255-2014; Hernandez-Rey, Juan Jose/N-5955-2014; Barrio, Juan/L-3227-2014; Zalewski, Piotr/H-7335-2013; Marti-Garcia, Salvador/F-3085-2011; Vaz, Pedro/K-2464-2013; Monge, Maria Roberta/G-9127-2012; Ridky, Jan/H-6184-2014; Zukanovich Funchal, Renata/C-5829-2013; Fernandez, Ester/K-9734-2014; Pimenta, Mario/M-1741-2013; Gomez Cadenas, Juan Jose/L-2003-2014; Ragazzi, Stefano/D-2463-2009; Roditi, Itzhak/O-7448-2014; Zuniga, Juan/P-4385-2014; Dracos, Marcos/K-2335-2012; Hallgren, Allan/A-8963-2013; de Groot, Nicolo/A-2675-2009; Katsanevas, Stavros/A-4297-2011; Ruiz, Alberto/E-4473-2011; branchini, paolo/A-4857-2011; Shellard, Ronald/G-4825-2012; Petrolini, Alessandro/H-3782-2011; Torassa, Ezio/I-1788-2012; Giacomelli, Paolo/B-8076-2009; Fruhwirth, Rudolf/H-2529-2012; Andreazza, Attilio/E-5642-2011; Botner, Olga/A-9110-2013; OI Zaitsev, Alexandre/0000-0002-4961-8368; Matteuzzi, Clara/0000-0002-4047-4521; DE MIN, ALBERTO/0000-0002-8130-9389; Demaria, Natale/0000-0003-0743-9465; Sannino, Mario/0000-0001-7700-8383; De Lotto, Barbara/0000-0003-3624-4480; Tabarelli de Fatis, Tommaso/0000-0001-6262-4685; Michelotto, Michele/0000-0001-6644-987X; Matorras, Francisco/0000-0003-4295-5668; Ferrer, Antonio/0000-0003-0532-711X; Rovelli, Tiziano/0000-0002-9746-4842; Fernandez-Alonso, Mercedes/0000-0002-1311-5275; Lozano-Bahilo, Julio/0000-0003-0613-140X; Olshevskiy, Alexander/0000-0002-8902-1793; Paganoni, Marco/0000-0003-2461-275X; Contreras Gonzalez, Jose Luis/0000-0001-7282-2394; Hernandez-Rey, Juan Jose/0000-0002-1527-7200; Barrio, Juan/0000-0002-0965-0259; Vaz, Pedro/0000-0002-7186-2359; Monge, Maria Roberta/0000-0003-1633-3195; Ridky, Jan/0000-0001-6697-1393; Zukanovich Funchal, Renata/0000-0001-6749-0022; Pimenta, Mario/0000-0002-2590-0908; Gomez Cadenas, Juan Jose/0000-0002-8224-7714; Ragazzi, Stefano/0000-0001-8219-2074; Roditi, Itzhak/0000-0003-2363-5626; Zuniga, Juan/0000-0002-1041-6451; Dracos, Marcos/0000-0003-0514-193X; Ruiz, Alberto/0000-0002-3639-0368; Shellard, Ronald/0000-0002-2983-1815; Petrolini, Alessandro/0000-0003-0222-7594; Andreazza, Attilio/0000-0001-5161-5759; Lacasta, Carlos/0000-0002-2623-6252; Torassa, Ezio/0000-0003-2321-0599 NR 58 TC 33 Z9 34 U1 0 U2 9 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 NOV 9 PY 1992 VL 386 IS 2 BP 471 EP 492 DI 10.1016/0550-3213(92)90574-U PG 22 WC Physics, Particles & Fields SC Physics GA KC702 UT WOS:A1992KC70200009 ER PT J AU GOCKSCH, A SHEN, Y AF GOCKSCH, A SHEN, Y TI PHASE-DIAGRAM OF THE N = 2 KAZAKOV-MIGDAL MODEL SO PHYSICAL REVIEW LETTERS LA English DT Article AB We have determined the phase diagram of the simplest version of a lattice model recently introduced by Kazakov and Migdal. Denoting by m0 and lambda the mass and the coupling of the scalar field in the model, we find a line of first-order phase transitions in the (m0,lambda) plane ending in a critical point where lambda is nonzero. Kazakov and Migdal speculate that their model of scalar field theory could induce QCD. Our work indicates that there is no continuum limit except at the critical end point. Whether or not a non-trivial continuum limit exists there requires a careful study of the renormalization-group properties of the model. RP BROOKHAVEN NATL LAB, DEPT PHYS, UPTON, NY 11973 USA. NR 6 TC 6 Z9 6 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 9 PY 1992 VL 69 IS 19 BP 2747 EP 2749 DI 10.1103/PhysRevLett.69.2747 PG 3 WC Physics, Multidisciplinary SC Physics GA JX245 UT WOS:A1992JX24500003 ER PT J AU ATWOOD, D AEPPLI, A SONI, A AF ATWOOD, D AEPPLI, A SONI, A TI EXTRACTING ANOMALOUS GLUON-TOP-QUARK EFFECTIVE COUPLINGS AT THE SUPERCOLLIDERS SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRIC-DIPOLE MOMENT; T-VIOLATION; TAU-LEPTONS; Z-DECAYS; CP AB Production of ttBAR by gluon fusion followed by t --> bW+, tBAR --> bW-, and W+/- --> e+/- v(e)(v(e)BAR) is studied to extract the CP-violating chromoelectric dipole moment form factor of the top quark. The fact that the spin of the top quark, in its rest frame, is in the direction of the e+ momentum facilitates the analysis. Expressions for the differential cross section and decays arc given. We find that at the Superconducting Super Collider or CERN Large Hadron Collider, it is possible to put a limit of 10(-20)g(s) to 10(-19)g(s) cm on these effective couplings through the use of "optimal observables." Naive observables such as simple triple product correlations are typically an order of magnitude less effective. RP ATWOOD, D (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 25 TC 96 Z9 96 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 NOV 9 PY 1992 VL 69 IS 19 BP 2754 EP 2757 DI 10.1103/PhysRevLett.69.2754 PG 4 WC Physics, Multidisciplinary SC Physics GA JX245 UT WOS:A1992JX24500005 ER PT J AU TANNER, CE LIVINGSTON, AE RAFAC, RJ SERPA, FG KUKLA, KW BERRY, HG YOUNG, L KURTZ, CA AF TANNER, CE LIVINGSTON, AE RAFAC, RJ SERPA, FG KUKLA, KW BERRY, HG YOUNG, L KURTZ, CA TI MEASUREMENT OF THE 6P2P3/2 STATE LIFETIME IN ATOMIC CESIUM SO PHYSICAL REVIEW LETTERS LA English DT Article ID PERTURBATION-THEORY; LASER EXCITATION; SPECTROSCOPY; SUMMATION; PHYSICS AB We present a precision experimental test of atomic many-body theory that is currently applied to the interpretation of recent parity-nonconservation experiments in atomic cesium. We report the first measurement of the Cs-133 6p P-2(3/2) state lifetime using resonant diode-laser excitation of a fast atomic beam. The lifetime result of 30.55 +/- 0.27 ns determines the absorption oscillator strength for the 6s S-2(1/2)-6p P-2(3/2) transition in cesium to be 0.7133 +/- 0.0064, and establishes the accuracy of recent relativistic many-body calculations of the dipole transition matrix element to 0.5%. C1 ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. RP TANNER, CE (reprint author), UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556, USA. RI Kurtz, Chalres/G-1037-2011 OI Kurtz, Chalres/0000-0003-2606-0864 NR 16 TC 34 Z9 34 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 NOV 9 PY 1992 VL 69 IS 19 BP 2765 EP 2767 DI 10.1103/PhysRevLett.69.2765 PG 3 WC Physics, Multidisciplinary SC Physics GA JX245 UT WOS:A1992JX24500008 ER PT J AU FUOSS, PH KISKER, DW LAMELAS, FJ STEPHENSON, GB IMPERATORI, P BRENNAN, S AF FUOSS, PH KISKER, DW LAMELAS, FJ STEPHENSON, GB IMPERATORI, P BRENNAN, S TI TIME-RESOLVED X-RAY-SCATTERING STUDIES OF LAYER-BY-LAYER EPITAXIAL-GROWTH SO PHYSICAL REVIEW LETTERS LA English DT Article ID CRYSTAL-GROWTH; SURFACE; GAAS AB We report the first time-resolved x-ray scattering study of the homoepitaxial growth of GaAs by organometallic vapor-phase epitaxy. The growth mode was determined to be layer-by-layer by observing almost-equal-to 1-Hz oscillations of the x-ray intensity from the 11l crystal truncation rod near the 110 position. We show that the spatial distribution of islands can be dynamically determined by measuring the x-ray diffuse scattering near the 110. Finally, we show that significant correlations exist between the locations of islands during layer-by-layer growth. C1 IBM CORP,RES DIV,YORKTOWN HTS,NY 10598. STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94309. CNR,IST TEOR & STRUTTURA ELETTR,AREA RIC ROMA,I-00016 MONTEROTONDO,ITALY. RP FUOSS, PH (reprint author), AT&T BELL LABS,MURRAY HILL,NJ 07974, USA. RI Imperatori, Patrizia/K-2260-2012 OI Imperatori, Patrizia/0000-0001-5143-9038 NR 15 TC 80 Z9 80 U1 1 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 9 PY 1992 VL 69 IS 19 BP 2791 EP 2794 DI 10.1103/PhysRevLett.69.2791 PG 4 WC Physics, Multidisciplinary SC Physics GA JX245 UT WOS:A1992JX24500015 ER PT J AU CHRZAN, DC MILLS, MJ AF CHRZAN, DC MILLS, MJ TI CRITICALITY IN THE PLASTIC-DEFORMATION OF NI3AL SO PHYSICAL REVIEW LETTERS LA English DT Article AB It is argued that the critical point of a nonequilibrium phase transition in the motion of dislocations results in the experimentally observed power-law creep rates in Ni3Al and related intermetallic alloys. A simple scaling argument is used to connect the critical exponents of the transition directly to the creep rate. A model of dislocation motion is constructed. The exponents predicted from the model are in agreement with those deduced from creep experiments. RP CHRZAN, DC (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94550, USA. NR 10 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 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 9 PY 1992 VL 69 IS 19 BP 2795 EP 2798 DI 10.1103/PhysRevLett.69.2795 PG 4 WC Physics, Multidisciplinary SC Physics GA JX245 UT WOS:A1992JX24500016 ER PT J AU WU, RQ FREEMAN, AJ AF WU, RQ FREEMAN, AJ TI SPIN-DENSITY AT THE FERMI LEVEL FOR MAGNETIC-SURFACES AND OVERLAYERS SO PHYSICAL REVIEW LETTERS LA English DT Article ID SCANNING TUNNELING MICROSCOPE; ATOM-DEEXCITATION SPECTROSCOPY; THIN-FILM MAGNETISM AB Results of calculations of the spin density at the Fermi energy for several illustrative examples-the clean Fe(110) surface and the O/Fe(110), Fe/Ni(111), and Ru/Ag(001) overlayer systems-using the full potential linearized augmented plane wave method demonstrate that this energy-sliced spin density differs substantially from the total spin density previously given in the literature. The difference of the density of states at E(F) between the two spin parts is found to play the key role. Its negative sign in the surface-vacuum region for Fe(110) and its sign reversal when oxygen is added as an overlayer explain the experimental results obtained by using spin-polarized metastable atom deexcitation spectroscopy. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP WU, RQ (reprint author), NORTHWESTERN UNIV,DEPT PHYS & ASTRON,EVANSTON,IL 60208, USA. RI Wu, Ruqian/C-1395-2013 OI Wu, Ruqian/0000-0002-6156-7874 NR 22 TC 52 Z9 53 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 NOV 9 PY 1992 VL 69 IS 19 BP 2867 EP 2870 DI 10.1103/PhysRevLett.69.2867 PG 4 WC Physics, Multidisciplinary SC Physics GA JX245 UT WOS:A1992JX24500034 ER PT J AU BIRDSALL, DL MCPHERSON, A AF BIRDSALL, DL MCPHERSON, A TI CRYSTAL-STRUCTURE DISPOSITION OF THYMIDYLIC ACID TETRAMER IN COMPLEX WITH RIBONUCLEASE-A SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID DIFFRACTION DATA; ACTIVE-SITE; X-RAY; PANCREATIC RIBONUCLEASE; NEUTRON-DIFFRACTION; 2.8-A RESOLUTION; REFINEMENT; BINDING; MECHANISM; D(PA)4 AB The crystal structure of ribonuclease A with bound thymidylic acid tetramer is reported at 2.5-angstrom resolution. The diffusion of the tetramer into native orthorhombic crystals of the ribonuclease allows for the formation of a structurally stable complex where the single-stranded nucleic acid enters and leaves the enzyme's catalytic region in a persistent 5'-3' direction. The binding of the tetramer to the enzyme's surface is facilitated and mediated by electrostatic interactions between basic protein residues and nucleotide phosphates. Two pyrimidine nucleotides are bound to the enzyme's active site in a manner similar to that observed for other complexes between ribonuclease A and nucleic acid oligomers. C1 UNIV CALIF RIVERSIDE,DEPT BIOCHEM,RIVERSIDE,CA 92521. RP BIRDSALL, DL (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,LIVERMORE,CA 94550, USA. FU NIGMS NIH HHS [5 F32 GM11235] NR 45 TC 31 Z9 31 U1 0 U2 3 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD NOV 5 PY 1992 VL 267 IS 31 BP 22230 EP 22236 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA JW719 UT WOS:A1992JW71900039 PM 1429575 ER PT J AU CHABRIER, G ASHCROFT, NW DEWITT, HE AF CHABRIER, G ASHCROFT, NW DEWITT, HE TI WHITE-DWARFS AS QUANTUM CRYSTALS SO NATURE LA English DT Article ID ONE-COMPONENT PLASMA; LUMINOSITY FUNCTIONS; MATTER; STATE; PHASE AB WHITE dwarfs are the most common endpoint of stellar evolution. Thermonuclear reactions have ceased, and the star settles into a compact object governed by relativistic, almost degenerate electrons. Bare nuclei of carbon and other heavier elements, normally considered as classical particles moving in the degenerate electron sea, are forced into a crystal lattice in the interior1 as the star cools, and a freezing front moves outward. Numerical simulations of the freezing of classical point charges in a uniform neutralizing background have been used to model the crystallization of white dwarfs2-4, but we show here that the classical approximation is not a good one: the energy per particle is significantly modified by quantum effects. The freezing process is then a transformation of a quantum liquid to a quantum solid, and the temperature of freezing may be reduced from the classical value. For lower mass stars particularly, the quantum corrections in liquid and solid seem to be comparable, and the physical conditions at freezing, classically typified by the ratio of the root-mean-square atomic displacement to the nearest-neighbour distance, are not greatly changed. Nevertheless, these new considerations may have an important effect on the cooling rate of white dwarfs, and thereby on their inferred evolution and ages. C1 CORNELL UNIV,ATOM & SOLID STATE PHYS LAB,ITHACA,NY 14853. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP CHABRIER, G (reprint author), ECOLE NORMALE SUPER LYON,PHYS LAB,F-69364 LYON 07,FRANCE. NR 24 TC 58 Z9 58 U1 0 U2 5 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD NOV 5 PY 1992 VL 360 IS 6399 BP 48 EP 50 DI 10.1038/360048a0 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JW717 UT WOS:A1992JW71700048 ER PT J AU WARBURTON, EK TOWNER, IS AF WARBURTON, EK TOWNER, IS TI RENORMALIZATION OF THE AXIAL CHARGE AT A-SIMILAR-TO-132 SO PHYSICS LETTERS B LA English DT Article ID 1ST-FORBIDDEN BETA-DECAY; LEAD REGION; MESONIC ENHANCEMENT; NUCLEI; TRANSITIONS; CURRENTS; RATES AB Mesonic-exchange contributions to the axial charge are evaluated in a shell-model study of the DELTAJ = 0 first-forbidden beta- decays of 133Sn(7/2-), 134Sn(0+) and 134 Sb(0-). The average enhancement of the axial charge over the impulse approximation is found to be (82 +/- 7)%. The theoretical value is in the range (58-70)%. Thus there is room for effects from other processes in the approximately (5-30)% range. C1 ATOM ENERGY CANADA LTD,CHALK RIVER LABS,CHALK RIVER K0J 1J0,ONTARIO,CANADA. RP WARBURTON, EK (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 23 TC 22 Z9 22 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD NOV 5 PY 1992 VL 294 IS 1 BP 1 EP 6 DI 10.1016/0370-2693(92)91629-N PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JW988 UT WOS:A1992JW98800001 ER PT J AU AITCHISON, IJR DOREY, N KLEINKREISLER, M MAVROMATOS, NE AF AITCHISON, IJR DOREY, N KLEINKREISLER, M MAVROMATOS, NE TI PHASE-STRUCTURE OF QED3 AT FINITE TEMPERATURE SO PHYSICS LETTERS B LA English DT Article ID CHIRAL-SYMMETRY-BREAKING; FIELD-THEORY; SUPERCONDUCTIVITY; DIMENSIONS; FLAVORS; PARITY; MODEL; MASS AB Dynamical symmetry breaking in three-dimensional QED with N fermion flavours i s considered at finite temperature, in the large N approximation. Using an approximate treatment of the Schwinger-Dyson equation for the fermion self-energy, we find that chiral symmetry is restored above a certain critical temperature which depends itself on N. We find that the ratio of the zero-momentum-zero-temperature fermion mass to the critical temperature has a large value compared with four-fermion theories, as had been suggested in a previous work with a momentum-independent self-energy. Evidence of a temperature-dependent critical N is shown to appear in this approximation. The phase diagram for spontaneous mass generation in the theory is presented in T-N space. C1 CERN,DIV THEORY,CH-1211 GENEVA 23,SWITZERLAND. LOS ALAMOS NATL LAB,DIV THEORET T8,LOS ALAMOS,NM 87545. RP AITCHISON, IJR (reprint author), DEPT THEORET PHYS,1 KEBLE RD,OXFORD OX1 3NP,ENGLAND. NR 20 TC 37 Z9 37 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD NOV 5 PY 1992 VL 294 IS 1 BP 91 EP 99 DI 10.1016/0370-2693(92)91645-P PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JW988 UT WOS:A1992JW98800017 ER PT J AU ANDERSEN, E BARNES, PD BLAES, R CHERNEY, M DELACRUZ, B DIEBOLD, GE DULNY, B FERNANDEZ, C FRANKLIN, G GARABATOS, C GARZON, JA GEIST, W GREINER, DE GRUHN, CR HAFIDOUNI, M HRUBEC, J JONES, PG JUDD, EG KUIPERS, JPM LADREM, M DEGUEVARA, PL LOVHOIDEN, G MACNAUGHTON, J MOSQUERA, J NATKANIEC, Z NELSON, JM NEUHOFER, G OGLE, WC DELOSHEROS, CP PLO, M PORTH, P POWELL, B QUINN, B RAMIL, A ROHRINGER, H SAKREJDA, I THORSTEINSEN, TF TRAXLER, J VOLTOLINI, C WOZNIAK, K YANEZ, A YEE, Y ZYBERT, R AF ANDERSEN, E BARNES, PD BLAES, R CHERNEY, M DELACRUZ, B DIEBOLD, GE DULNY, B FERNANDEZ, C FRANKLIN, G GARABATOS, C GARZON, JA GEIST, W GREINER, DE GRUHN, CR HAFIDOUNI, M HRUBEC, J JONES, PG JUDD, EG KUIPERS, JPM LADREM, M DEGUEVARA, PL LOVHOIDEN, G MACNAUGHTON, J MOSQUERA, J NATKANIEC, Z NELSON, JM NEUHOFER, G OGLE, WC DELOSHEROS, CP PLO, M PORTH, P POWELL, B QUINN, B RAMIL, A ROHRINGER, H SAKREJDA, I THORSTEINSEN, TF TRAXLER, J VOLTOLINI, C WOZNIAK, K YANEZ, A YEE, Y ZYBERT, R TI STRANGENESS PRODUCTION AT MID-RAPIDITY IN S+PB COLLISIONS AT 200 GEV/C PER NUCLEON SO PHYSICS LETTERS B LA English DT Article ID HEAVY-ION COLLISIONS; SULFUR AB Experimental evidence is presented for a source of unusually high strangeness content located at mid-rapidity in 200 GeV/c per nucleon collisions of S-32 projectiles with a Pb target. The enhancement is not seen in p + Pb reactions measured in the same apparatus at the same energy. This source becomes dominant for central collisions. C1 CARNEGIE MELLON UNIV,DEPT PHYS,PITTSBURGH,PA 15213. UNIV LOUIS PASTEUR,INST NATL PHYS NUCL PHYS PARTICULES,CNRS,CTR RECH NUCL,F-67037 STRASBOURG,FRANCE. CREIGHTON UNIV,DEPT PHYS,OMAHA,NE 68178. CIEMAT,DIV FIS PARTICULAS,E-28040 MADRID,SPAIN. INST FIZ JADROWEJ,PL-30055 KRAKOW,POLAND. UNIV SANTIAGO,DEPT FIS PARTICULAS,E-15706 SANTIAGO,SPAIN. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. INST HOCHENERGIEPHYS,A-1050 VIENNA,AUSTRIA. UNIV BIRMINGHAM,DEPT PHYS,BIRMINGHAM B15 2TT,W MIDLANDS,ENGLAND. UNIV YORK,DEPT PHYS,YORK YO1 5DD,N YORKSHIRE,ENGLAND. CERN,CH-1211 GENEVA 23,SWITZERLAND. RP ANDERSEN, E (reprint author), UNIV BERGEN,DEPT PHYS,N-5007 BERGEN,NORWAY. RI de la Cruz, Begona/K-7552-2014; Plo Casasus, Maximo/M-1445-2014; Ramil, Alberto/B-4698-2008; Yanez, Armando/L-2957-2014 OI Quinn, Brian/0000-0003-2800-986X; Plo Casasus, Maximo/0000-0002-2289-918X; Franklin, Gregg/0000-0003-4176-1378; Perez de los Heros, Carlos/0000-0002-2084-5866; Ramil, Alberto/0000-0002-5333-9425; Yanez, Armando/0000-0003-4626-7993 NR 24 TC 33 Z9 33 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD NOV 5 PY 1992 VL 294 IS 1 BP 127 EP 130 DI 10.1016/0370-2693(92)91651-O PG 4 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JW988 UT WOS:A1992JW98800023 ER PT J AU BUSKULIC, D DECAMP, D GOY, C LEES, JP MINARD, MN MOURS, B ALEMANY, R ARIZTIZABAL, F COMAS, P CRESPO, JM DELFINO, M FERNANDEZ, E GAITAN, V GARRIDO, L PACHECO, A PASCUAL, A CREANZA, D DEPALMA, M FARILLA, A IASELLI, G MAGGI, G MAGGI, M NATALI, S NUZZO, S QUATTROMINI, M RANIERI, A RASO, G ROMANO, F RUGGIERI, F SELVAGGI, G SILVESTRIS, L TEMPESTA, P ZITO, G GAO, Y HU, H HUANG, D HUANG, X LIN, J LOU, J QIAO, C WANG, T XIE, Y XU, D XU, R ZHANG, J ZHAO, W ATWOOD, WB BAUERDICK, LAT BLUCHER, E BONVICINI, G BOSSI, F BOUDREAU, J BURNETT, TH DREVERMANN, H FORTY, RW HAGELBERG, R HARVEY, J HAYWOOD, S HILGART, J JACOBSEN, R JOST, B KNOBLOCH, J LANCON, E LEHRAUS, I LOHSE, T LUSIANI, A MARTINEZ, M MATO, P MATTISON, T MEINHARD, H MENARY, S MEYER, T MINTEN, A MIQUEL, R MOSER, HG NASH, J PALAZZI, P PERLAS, JA RANJARD, F REDLINGER, G ROLANDI, L ROTH, A ROTHBERG, J RUAN, T SAICH, M SCHLATTER, D SCHMELLING, M SEFKOW, F TEJESSY, W WACHSMUTH, H WIEDENMANN, W WILDISH, T WITZELING, W WOTSCHACK, J AJALTOUNI, Z BADAUD, F BARDADINOTWINOWSKA, M BENCHEIKH, AM ELFELLOUS, R FALVARD, A GAY, P GUICHENEY, C HENRARD, P JOUSSET, J MICHEL, B MONTRET, JC PALLIN, D PERRET, P PIETRZYK, B PRORIOL, J PRULHIERE, F STIMPFL, G FEARNLEY, T HANSEN, JD HANSEN, JR HANSEN, PH MOLLERUD, R NILSSON, BS EFTHYMIOPOULOS, I KYRIAKIS, A SIMOPOULOU, E VAYAKI, A ZACHARIADOU, K BADIER, J BLONDEL, A BONNEAUD, G BRIENT, JC FOUQUE, G GAMESS, A ORTEU, S ROSOWSKY, A ROUGE, A RUMPF, M TANAKA, R VIDEAU, H CANDLIN, DJ PARSONS, MI VEITCH, E MONETA, L PARRINI, G CORDEN, M GEORGIOPOULOS, C IKEDA, M LANNUTTI, J LEVINTHAL, D MERMIKIDES, M SAWYER, L WASSERBAECH, S ANTONELLI, A BALDINI, R BENCIVENNI, G BOLOGNA, G CAMPANA, P CAPON, G CERUTTI, F CHIARELLA, V DETTORREPIAZZOLI, B FELICI, G LAURELLI, P MANNOCCHI, G MURTAS, F MURTAS, GP PASSALACQUA, L PEPEALTARELLI, M PICCHI, P ALTOON, B BOYLE, O COLRAIN, P TENHAVE, I LYNCH, JG MAITLAND, W MORTON, WT RAINE, C SCARR, JM SMITH, K THOMPSON, AS TURNBULL, RM BRANDL, B BRAUN, O GEIGES, R GEWENIGER, C HANKE, P HEPP, V KLUGE, EE MAUMARY, Y PUTZER, A RENSCH, B STAHL, A TITTEL, K WUNSCH, M BELK, AT BEUSELINCK, R BINNIE, DM CAMERON, W CATTANEO, M COLLING, DJ DORNAN, PJ DUGEAY, S GREENE, AM HASSARD, JF LIESKE, NM PATTON, SJ PAYNE, DG PHILLIPS, MJ SEDGBEER, JK TOMALIN, IR WRIGHT, AG GIRTLER, P KUHN, D RUDOLPH, G BOWDERY, CK BRODBECK, TJ FINCH, AJ FOSTER, F HUGHES, G JACKSON, D KEEMER, NR NUTTALL, M PATEL, A SLOAN, T SNOW, SW WHELAN, EP BARCZEWSKI, T KLEINKNECHT, K RAAB, J RENK, B ROEHN, S SANDER, HG SCHMIDT, H STEEG, F WALTHER, SM WOLF, B AUBERT, JJ BENCHOUK, C BERNARD, V BONISSENT, A CARR, J COYLE, P DRINKARD, J ETIENNE, F PAPALEXIOU, S PAYRE, P QIAN, Z ROUSSEAU, D SCHWEMLING, P TALBY, M ADLUNG, S BAUER, C BLUM, W BROWN, D COWAN, G DEHNING, B DIETL, H DYDAK, F FERNANDEZBOSMAN, M FRANK, M HALLEY, AW LAUBER, J LUTJENS, G LUTZ, G MANNER, W RICHTER, R SCHRODER, J SCHWARZ, AS SETTLES, R SEYWERD, H STIERLIN, U STIEGLER, U STDENIS, R TAKASHIMA, M THOMAS, J WOLF, G BERTIN, V BOUCROT, J CALLOT, O CHEN, X CORDIER, A DAVIER, M GRIVAZ, JF HEUSSE, P JANOT, P KIM, DW LEDIBERDER, F LEFRANCOIS, J LUTZ, AM SCHUNE, MH VEILLET, JJ VIDEAU, I ZHANG, Z ZOMER, F ABBANEO, D AMENDOLIA, SR BAGLIESI, G BATIGNANI, G BOSISIO, L BOTTIGLI, U BRADASCHIA, C CARPINELLI, M CIOCCI, MA DELLORSO, R FERRANTE, I FIDECARO, F FOA, L FOCARDI, E FORTI, F GIASSI, A GIORGI, MA LIGABUE, F MANNELLI, EB MARROCCHESI, PS MESSINEO, A PALLA, F RIZZO, G SANGUINETTI, G STEINBERGER, J TENCHINI, R TONELLI, G TRIGGIANI, G VANNINI, C VENTURI, A VERDINI, PG WALSH, J CARTER, JM GREEN, MG MARCH, PV MIR, LM MEDCALF, T QUAZI, IS STRONG, JA WEST, LR BOTTERILL, DR CLIFFT, RW EDGECOCK, TR EDWARDS, M FISHER, SM JONES, TJ NORTON, PR SALMON, DP THOMPSON, JC BLOCHDEVAUX, B COLAS, P KOZANECKI, W LEMAIRE, MC LOCCI, E LOUCATOS, S MONNIER, E PEREZ, P PERRIER, F RANDER, J RENARDY, JF ROUSSARIE, A SCHULLER, JP SCHWINDLING, J SIMOHAND, D VALLAGE, B JOHNSON, RP LITKE, AM TAYLOR, G WEAR, J ASHMAN, JG BABBAGE, W BOOTH, CN BUTTAR, C CARNEY, RE CARTWRIGHT, S COMBLEY, F HATFIELD, F REEVES, P THOMPSON, LF BARBERIO, E BRANDT, S GRUPEN, C MIRABITO, L SCHAFER, U GANIS, G GIANNINI, G GOBBO, B RAGUSA, F BELLANTONI, L CINABRO, D CONWAY, JS COWEN, DF FENG, Z FERGUSON, DPS GAO, YS GRAHL, J HARTON, JL JARED, RC LECLAIRE, BW LISHKA, C PAN, YB PATER, JR PUSZTASZERI, JF SAADI, Y SHARMA, V SCHMITT, M SHI, ZH TANG, YH WALSH, AM WEBER, FV WHITNEY, MH WU, SL WU, X ZOBERNIG, G AF BUSKULIC, D DECAMP, D GOY, C LEES, JP MINARD, MN MOURS, B ALEMANY, R ARIZTIZABAL, F COMAS, P CRESPO, JM DELFINO, M FERNANDEZ, E GAITAN, V GARRIDO, L PACHECO, A PASCUAL, A CREANZA, D DEPALMA, M FARILLA, A IASELLI, G MAGGI, G MAGGI, M NATALI, S NUZZO, S QUATTROMINI, M RANIERI, A RASO, G ROMANO, F RUGGIERI, F SELVAGGI, G SILVESTRIS, L TEMPESTA, P ZITO, G GAO, Y HU, H HUANG, D HUANG, X LIN, J LOU, J QIAO, C WANG, T XIE, Y XU, D XU, R ZHANG, J ZHAO, W ATWOOD, WB BAUERDICK, LAT BLUCHER, E BONVICINI, G BOSSI, F BOUDREAU, J BURNETT, TH DREVERMANN, H FORTY, RW HAGELBERG, R HARVEY, J HAYWOOD, S HILGART, J JACOBSEN, R JOST, B KNOBLOCH, J LANCON, E LEHRAUS, I LOHSE, T LUSIANI, A MARTINEZ, M MATO, P MATTISON, T MEINHARD, H MENARY, S MEYER, T MINTEN, A MIQUEL, R MOSER, HG NASH, J PALAZZI, P PERLAS, JA RANJARD, F REDLINGER, G ROLANDI, L ROTH, A ROTHBERG, J RUAN, T SAICH, M SCHLATTER, D SCHMELLING, M SEFKOW, F TEJESSY, W WACHSMUTH, H WIEDENMANN, W WILDISH, T WITZELING, W WOTSCHACK, J AJALTOUNI, Z BADAUD, F BARDADINOTWINOWSKA, M BENCHEIKH, AM ELFELLOUS, R FALVARD, A GAY, P GUICHENEY, C HENRARD, P JOUSSET, J MICHEL, B MONTRET, JC PALLIN, D PERRET, P PIETRZYK, B PRORIOL, J PRULHIERE, F STIMPFL, G FEARNLEY, T HANSEN, JD HANSEN, JR HANSEN, PH MOLLERUD, R NILSSON, BS EFTHYMIOPOULOS, I KYRIAKIS, A SIMOPOULOU, E VAYAKI, A ZACHARIADOU, K BADIER, J BLONDEL, A BONNEAUD, G BRIENT, JC FOUQUE, G GAMESS, A ORTEU, S ROSOWSKY, A ROUGE, A RUMPF, M TANAKA, R VIDEAU, H CANDLIN, DJ PARSONS, MI VEITCH, E MONETA, L PARRINI, G CORDEN, M GEORGIOPOULOS, C IKEDA, M LANNUTTI, J LEVINTHAL, D MERMIKIDES, M SAWYER, L WASSERBAECH, S ANTONELLI, A BALDINI, R BENCIVENNI, G BOLOGNA, G CAMPANA, P CAPON, G CERUTTI, F CHIARELLA, V DETTORREPIAZZOLI, B FELICI, G LAURELLI, P MANNOCCHI, G MURTAS, F MURTAS, GP PASSALACQUA, L PEPEALTARELLI, M PICCHI, P ALTOON, B BOYLE, O COLRAIN, P TENHAVE, I LYNCH, JG MAITLAND, W MORTON, WT RAINE, C SCARR, JM SMITH, K THOMPSON, AS TURNBULL, RM BRANDL, B BRAUN, O GEIGES, R GEWENIGER, C HANKE, P HEPP, V KLUGE, EE MAUMARY, Y PUTZER, A RENSCH, B STAHL, A TITTEL, K WUNSCH, M BELK, AT BEUSELINCK, R BINNIE, DM CAMERON, W CATTANEO, M COLLING, DJ DORNAN, PJ DUGEAY, S GREENE, AM HASSARD, JF LIESKE, NM PATTON, SJ PAYNE, DG PHILLIPS, MJ SEDGBEER, JK TOMALIN, IR WRIGHT, AG GIRTLER, P KUHN, D RUDOLPH, G BOWDERY, CK BRODBECK, TJ FINCH, AJ FOSTER, F HUGHES, G JACKSON, D KEEMER, NR NUTTALL, M PATEL, A SLOAN, T SNOW, SW WHELAN, EP BARCZEWSKI, T KLEINKNECHT, K RAAB, J RENK, B ROEHN, S SANDER, HG SCHMIDT, H STEEG, F WALTHER, SM WOLF, B AUBERT, JJ BENCHOUK, C BERNARD, V BONISSENT, A CARR, J COYLE, P DRINKARD, J ETIENNE, F PAPALEXIOU, S PAYRE, P QIAN, Z ROUSSEAU, D SCHWEMLING, P TALBY, M ADLUNG, S BAUER, C BLUM, W BROWN, D COWAN, G DEHNING, B DIETL, H DYDAK, F FERNANDEZBOSMAN, M FRANK, M HALLEY, AW LAUBER, J LUTJENS, G LUTZ, G MANNER, W RICHTER, R SCHRODER, J SCHWARZ, AS SETTLES, R SEYWERD, H STIERLIN, U STIEGLER, U STDENIS, R TAKASHIMA, M THOMAS, J WOLF, G BERTIN, V BOUCROT, J CALLOT, O CHEN, X CORDIER, A DAVIER, M GRIVAZ, JF HEUSSE, P JANOT, P KIM, DW LEDIBERDER, F LEFRANCOIS, J LUTZ, AM SCHUNE, MH VEILLET, JJ VIDEAU, I ZHANG, Z ZOMER, F ABBANEO, D AMENDOLIA, SR BAGLIESI, G BATIGNANI, G BOSISIO, L BOTTIGLI, U BRADASCHIA, C CARPINELLI, M CIOCCI, MA DELLORSO, R FERRANTE, I FIDECARO, F FOA, L FOCARDI, E FORTI, F GIASSI, A GIORGI, MA LIGABUE, F MANNELLI, EB MARROCCHESI, PS MESSINEO, A PALLA, F RIZZO, G SANGUINETTI, G STEINBERGER, J TENCHINI, R TONELLI, G TRIGGIANI, G VANNINI, C VENTURI, A VERDINI, PG WALSH, J CARTER, JM GREEN, MG MARCH, PV MIR, LM MEDCALF, T QUAZI, IS STRONG, JA WEST, LR BOTTERILL, DR CLIFFT, RW EDGECOCK, TR EDWARDS, M FISHER, SM JONES, TJ NORTON, PR SALMON, DP THOMPSON, JC BLOCHDEVAUX, B COLAS, P KOZANECKI, W LEMAIRE, MC LOCCI, E LOUCATOS, S MONNIER, E PEREZ, P PERRIER, F RANDER, J RENARDY, JF ROUSSARIE, A SCHULLER, JP SCHWINDLING, J SIMOHAND, D VALLAGE, B JOHNSON, RP LITKE, AM TAYLOR, G WEAR, J ASHMAN, JG BABBAGE, W BOOTH, CN BUTTAR, C CARNEY, RE CARTWRIGHT, S COMBLEY, F HATFIELD, F REEVES, P THOMPSON, LF BARBERIO, E BRANDT, S GRUPEN, C MIRABITO, L SCHAFER, U GANIS, G GIANNINI, G GOBBO, B RAGUSA, F BELLANTONI, L CINABRO, D CONWAY, JS COWEN, DF FENG, Z FERGUSON, DPS GAO, YS GRAHL, J HARTON, JL JARED, RC LECLAIRE, BW LISHKA, C PAN, YB PATER, JR PUSZTASZERI, JF SAADI, Y SHARMA, V SCHMITT, M SHI, ZH TANG, YH WALSH, AM WEBER, FV WHITNEY, MH WU, SL WU, X ZOBERNIG, G TI OBSERVATION OF THE SEMILEPTONIC DECAYS OF BS AND LAMBDA-B HADRONS AT LEP SO PHYSICS LETTERS B LA English DT Article ID DS-MESONS; PARTICLE; BEAUTY; ALEPH AB In 450000 hadronic Z decays recorded with the ALEPH detector at LEP, the yields of D(s)-l+ and LAMBDA(c)+l- combinations have been measured. 16.0 +/- 4.3 D(s)-l+ combinations were observed in the D(s)- --> phipi- channel and 17.0 +/- 4.5 combinations were observed in the D(s)- --> K*0K- channel. 21.0 +/- 5.0 LAMBDA(c)+l- combinations were observed, with the LAMBDA(c)+ reconstructed in the decay mode LAMBDA(c)+ --> pK-pi+. These events provide evidence for the decays B(s) --> D(s)-Xl+nu and LAMBDA(b) --> LAMBDA(c)+Xl-nuBAR. Assuming that the B(s) and LAMBDA(b) semileptonic decays are dominantly three-body, these observed yields, after background subtraction, translate into the following product branching ratios: Br(bBAR --> B(s))Br(B(s) --> D(s)-Xl+nu) = 0.040 +/- 0.011 +0.010/-0.012, Br(b --> LAMBDA(b))Br(LAMBDA(b) --> LAMBDA(c)+Xl-nuBAR) = 0.030 +/- 0.007 +/- 0.009. C1 UNIV AUTONOMA BARCELONA,INST FIS ALTES ENERGIES,E-08193 BARCELONA,SPAIN. UNIV BARI,DIPARTIMENTO FIS,I-70126 BARI,ITALY. IST NAZL FIS NUCL,BARI,ITALY. CHINESE ACAD SCI,INST HIGH ENERGY PHYS,BEIJING,PEOPLES R CHINA. CERN,EUROPEAN LAB PARTICLE PHYS,CH-1211 GENEVA 23,SWITZERLAND. UNIV CLERMONT FERRAND,PHYS CORPUSCULAIRE LAB,CNRS,INST NATL PHYS NUCL & PHYS PARTICULES,CLERMONT,FRANCE. NIELS BOHR INST,DK-2100 COPENHAGEN,DENMARK. DEMOCRITOS NUCL RES CTR,GR-15310 ATHENS,GREECE. ECOLE POLYTECH,PHYS NUCL & HAUTES ENERGIES LAB,CNRS,F-91128 PALAISEAU,FRANCE. UNIV EDINBURGH,DEPT PHYS,EDINBURGH EH9 3JZ,MIDLOTHIAN,SCOTLAND. UNIV FLORENCE,IST NAZL FIS NUCL,DIPARTIMENTO FIS,I-50125 FLORENCE,ITALY. FLORIDA STATE UNIV,SUPERCOMP COMP RES INST,TALLAHASSEE,FL 32306. FLORIDA STATE UNIV,DEPT PHYS,TALLAHASSEE,FL 32306. IST NAZL FIS NUCL,NAZL LAB,I-00044 FRASCATI,ITALY. UNIV GLASGOW,DEPT PHYS & ASTRON,GLASGOW G12 8QQ,SCOTLAND. UNIV HEIDELBERG,INST HOCHENERGIEPHYS,W-6900 HEIDELBERG,GERMANY. UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED,DEPT PHYS,LONDON SW7 2BZ,ENGLAND. UNIV INNSBRUCK,INST EXPTL PHYS,A-6020 INNSBRUCK,AUSTRIA. UNIV LANCASTER,DEPT PHYS,LANCASTER LA1 4YB,ENGLAND. UNIV MAINZ,INST PHYS,W-6500 MAINZ,GERMANY. FAC SCI LUMINY,CTR PHYS PARTICULES,CNRS,INST NATL PHYS NUCL & PHYS PARTICULES,F-13288 MARSEILLE,FRANCE. MAX PLANCK INST PHYS & ASTROPHYS,WERNER HEISENBERG INST PHYS,W-8000 MUNICH 40,GERMANY. UNIV PARIS 11,ACCELERATEUR LINEAIRE LAB,CNRS,F-91405 ORSAY,FRANCE. UNIV PISA,IST NAZL FIS NUCL,DIPARTIMENTO FIS,I-56100 PISA,ITALY. SCUOLA NORMALE SUPER PISA,I-56100 PISA,ITALY. UNIV LONDON,ROYAL HOLLOWAY & BEDFORD NEW COLL,DEPT PHYS,SURREY TW20 0EX,ENGLAND. RUTHERFORD APPLETON LAB,DEPT PARTICLE PHYS,DIDCOT OX11 0QX,OXON,ENGLAND. CENS,DAPNIA,SERV PHYS PARTICULES,F-91191 GIF SUR YVETTE,FRANCE. UNIV CALIF SANTA CRUZ,INST PARTICLE PHYS,SANTA CRUZ,CA 95064. UNIV SHEFFIELD,DEPT PHYS,SHEFFIELD S3 7RH,S YORKSHIRE,ENGLAND. UNIV SIEGEN,FACHBEREICH PHYS,W-5900 SIEGEN,GERMANY. UNIV TRIESTE,DIPARTIMENTO FIS,I-34127 TRIESTE,ITALY. IST NAZL FIS NUCL,TRIESTE,ITALY. UNIV WISCONSIN,DEPT PHYS,MADISON,WI 53706. STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. UNIV WASHINGTON,SEATTLE,WA 98195. UNIV TURIN,IST FIS GEN,I-10124 TURIN,ITALY. NAPLES UNIV,DIPARTIMENTO SCI FIS,I-80134 NAPLES,ITALY. CNR,IST COSMO GEOFIS,TURIN,ITALY. CERN,DIV PPE,CH-1211 GENEVA 23,SWITZERLAND. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP BUSKULIC, D (reprint author), CNRS,INST NATL PHYS NUCL & PHYS PARTICULES,PHYS PARTICULES LAB,F-74019 ANNECY LE VIEUX,FRANCE. RI Bosman, Martine/J-9917-2014; Fernandez, Enrique/L-5387-2014; Mir, Lluisa-Maria/G-7212-2015; ciocci, maria agnese /I-2153-2015; Hansen, John/B-9058-2015; Lusiani, Alberto/N-2976-2015; Marrocchesi, Pier Simone/N-9068-2015; Lusiani, Alberto/A-3329-2016; Murtas, Fabrizio/B-5729-2012; Booth, Christopher/B-5263-2016; Pacheco Pages, Andres/C-5353-2011; Ferrante, Isidoro/F-1017-2012; Colas, Paul/F-2876-2013; Delfino, Manuel/A-1545-2012; ANTONELLI, ANTONELLA/C-6238-2011; Buttar, Craig/D-3706-2011; Stahl, Achim/E-8846-2011; Passalacqua, Luca/F-5127-2011; St.Denis, Richard/C-8997-2012; Forti, Francesco/H-3035-2011; Focardi, Ettore/E-7376-2012; Venturi, Andrea/J-1877-2012; Perrier, Frederic/A-5953-2011; Rolandi, Luigi (Gigi)/E-8563-2013; OI Bosman, Martine/0000-0002-7290-643X; Fernandez, Enrique/0000-0002-6405-9488; Mir, Lluisa-Maria/0000-0002-4276-715X; ciocci, maria agnese /0000-0003-0002-5462; Hansen, John/0000-0002-8422-5543; Lusiani, Alberto/0000-0002-6876-3288; Marrocchesi, Pier Simone/0000-0003-1966-140X; Lusiani, Alberto/0000-0002-6876-3288; Booth, Christopher/0000-0002-6051-2847; Pacheco Pages, Andres/0000-0001-8210-1734; Ferrante, Isidoro/0000-0002-0083-7228; Delfino, Manuel/0000-0002-9468-4751; Stahl, Achim/0000-0002-8369-7506; Forti, Francesco/0000-0001-6535-7965; Focardi, Ettore/0000-0002-3763-5267; Rolandi, Luigi (Gigi)/0000-0002-0635-274X; Miquel, Ramon/0000-0002-6610-4836 NR 36 TC 39 Z9 39 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 NOV 5 PY 1992 VL 294 IS 1 BP 145 EP 156 DI 10.1016/0370-2693(92)91654-R PG 12 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JW988 UT WOS:A1992JW98800026 ER PT J AU ZHANG, Y PAVLOSKY, MA BROWN, CA WESTRE, TE HEDMAN, B HODGSON, KO SOLOMON, EI AF ZHANG, Y PAVLOSKY, MA BROWN, CA WESTRE, TE HEDMAN, B HODGSON, KO SOLOMON, EI TI SPECTROSCOPIC AND THEORETICAL DESCRIPTION OF THE ELECTRONIC-STRUCTURE OF THE S = 3/2 NITROSYL COMPLEX OF NONHEME IRON ENZYMES SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Note ID X-RAY ABSORPTION; SOYBEAN LIPOXYGENASE-1; ACTIVE-SITE; PARAMAGNETIC-RES; SUBSTRATE; MOSSBAUER; SPECTRA; FE-2+; STATE C1 STANFORD UNIV,DEPT CHEM,STANFORD,CA 94305. STANFORD UNIV,STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94305. NR 30 TC 57 Z9 57 U1 1 U2 4 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 NOV 4 PY 1992 VL 114 IS 23 BP 9189 EP 9191 DI 10.1021/ja00049a062 PG 3 WC Chemistry, Multidisciplinary SC Chemistry GA JW797 UT WOS:A1992JW79700062 ER PT J AU JEANLOZ, R ONEILL, B PASTERNAK, MP TAYLOR, RD BOHLEN, SR AF JEANLOZ, R ONEILL, B PASTERNAK, MP TAYLOR, RD BOHLEN, SR TI MOSSBAUER-SPECTROSCOPY OF MG0.9FE0.1SIO3 PEROVSKITE SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID LOWER MANTLE CONDITIONS; BEARING SILICATE MELTS; REDOX EQUILIBRIA; (MG,FE)SIO3 PEROVSKITE; CRYSTAL-CHEMISTRY; IRON; PRESSURE; TEMPERATURE; GARNETS; MGSIO3 AB Ambient pressure Mossbauer spectra of (Mg0.9Fe0.1SiO3)-Fe-57 perovskite synthesized at pressure-temperature conditions of approximately 50 GPa and 1700 K show that the iron is entirely high-spin Fe2+ and appears to be primarily located in the octahedral site within the crystal structure. We observe broad Mossbauer lines, suggesting a distribution of electric-field gradients caused by disorder associated with the Fe ions. Also, the perovskite exhibits magnetic ordering at temperatures < 5 K, implying that there is a magnetic contribution to the absolute ("third-law") entropy of this phase. C1 TEL AVIV UNIV,SCH PHYS & ASTRON,IL-69978 TEL AVIV,ISRAEL. LOS ALAMOS NATL LAB,DIV PHYS,LOS ALAMOS,NM 87545. US GEOL SURVEY,MENLO PK,CA 94025. RP JEANLOZ, R (reprint author), UNIV CALIF BERKELEY,DEPT GEOL & GEOPHYS,BERKELEY,CA 94720, USA. NR 39 TC 9 Z9 9 U1 1 U2 2 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 NOV 3 PY 1992 VL 19 IS 21 BP 2135 EP 2138 DI 10.1029/92GL02461 PG 4 WC Geosciences, Multidisciplinary SC Geology GA JY496 UT WOS:A1992JY49600008 ER PT J AU READE, RP BERDAHL, P RUSSO, RE GARRISON, SM AF READE, RP BERDAHL, P RUSSO, RE GARRISON, SM TI LASER DEPOSITION OF BIAXIALLY TEXTURED YTTRIA-STABILIZED ZIRCONIA BUFFER LAYERS ON POLYCRYSTALLINE METALLIC ALLOYS FOR HIGH CRITICAL CURRENT Y-BA-CU-O THIN-FILMS SO APPLIED PHYSICS LETTERS LA English DT Article ID YBA2CU3O7-X FILMS; SI AB Pulsed laser deposition of yttria-stabilized zirconia (YSZ) layers on polycrystalline metallic alloy substrates is used to produce an intermediate layer for YBa2Cu3O7-delta (YBCO) thin-film growth. The desired (001) YSZ texture is obtained at 1.0 mTorr oxygen pressure and 70-degrees-C. Significant improvement in (001) texturing is demonstrated by using an ion beam to assist growth. Argon-ion-assisted growth produces layers with alignment of the in-plane crystal axes in addition to the (001)-normal texture. Highly c-axis-oriented biaxially aligned YBCO thin films can be deposited on these layers, with T(c)(R=0)=92 K and J(c)(77 K, B=0 T)=6 X 10(5) A/cm2 and J(c) (77 K, 0.4 T) = 8 X 10(4) A/cm2. With further improvement of the YSZ texture, the YBCO current-carrying capacity of films on polycrystalline metallic alloys may approach that of films on single-crystal substrates. C1 LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,BERKELEY,CA 94720. CONDUCTUS INC,SUNNYVALE,CA 94086. NR 15 TC 232 Z9 236 U1 3 U2 16 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 NOV 2 PY 1992 VL 61 IS 18 BP 2231 EP 2233 DI 10.1063/1.108277 PG 3 WC Physics, Applied SC Physics GA JW461 UT WOS:A1992JW46100036 ER PT J AU PAYNE, SA SMITH, LK KWAY, WL TASSANO, JB KRUPKE, WF AF PAYNE, SA SMITH, LK KWAY, WL TASSANO, JB KRUPKE, WF TI THE MECHANISM OF TM -] HO ENERGY-TRANSFER IN LIYF4 SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID OPTICAL-SPECTRUM; MU-M; LASER; SR1-XCEXF2+X; PERFORMANCE; EFFICIENCY; OPERATION; DYNAMICS; YAG; YLF AB The energy transfer properties of Tm, Ho:LiYF4 are examined, and special attention is given to the Tm(F-3(4)) --> Ho(I-5(7)) transfer dynamics and equilibration. The measured transfer times are compared with the values calculated on the basis of the static Forster-Dexter and the migration-assisted Burshtein energy transfer models (which require only spectral information and rare-earth concentrations as input data). The detection of anomalously fast measured transfer rates at high Tm doping levels is interpreted within the context of percolation theory, since migration pathways from the excited Tm ion to a Ho ion must necessarily exist above a particular threshold concentration. Lastly, it is suggested that the use of low Tm concentrations below the percolation threshold may serve to minimize the Auger upconversion losses, and also will shift the excited-state equilibrium to the Ho population; this type of scenario requires that the Tm ions be pumped directly into the F-3(4) state with 1.68 mum InGaAs diode sources. RP PAYNE, SA (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 5508,LIVERMORE,CA 94550, USA. NR 36 TC 42 Z9 43 U1 2 U2 6 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 NOV 2 PY 1992 VL 4 IS 44 BP 8525 EP 8542 DI 10.1088/0953-8984/4/44/014 PG 18 WC Physics, Condensed Matter SC Physics GA JX098 UT WOS:A1992JX09800014 ER PT J AU ALHASSID, Y BUSH, BW AF ALHASSID, Y BUSH, BW TI NUCLEAR-LEVEL DENSITIES IN THE STATIC-PATH APPROXIMATION .1. A SOLVABLE MODEL SO NUCLEAR PHYSICS A LA English DT Article ID PARTITION-FUNCTION AB We investigate the static-path approximation (SPA) and mean-field approximation (MFA) for the level density within a solvable SU(2) model. Comparing the SPA level density to the MFA one, we find an enhancement with a great sensitivity to the interaction strength, in agreement with exact analytic results. This enhancement compensates for a corresponding suppression which occurs at negative temperatures. The saddle-point approximation used in converting the partition function to the level density works well at all but low energies. C1 LOS ALAMOS NATL LAB,DIV THEORET,GRP T2,MS B243,LOS ALAMOS,NM 87545. YALE UNIV,CTR THEORET PHYS,SLOANE PHYS LAB,NEW HAVEN,CT 06511. YALE UNIV,AW WRIGHT NUCL STRUCT LAB,NEW HAVEN,CT 06511. OI Bush, Brian/0000-0003-2864-7028 NR 10 TC 40 Z9 40 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD NOV 2 PY 1992 VL 549 IS 1 BP 43 EP 58 DI 10.1016/0375-9474(92)90066-S PG 16 WC Physics, Nuclear SC Physics GA JY883 UT WOS:A1992JY88300003 ER PT J AU MOLLER, P NIX, JR AF MOLLER, P NIX, JR TI STABILITY AND DECAY OF NUCLEI AT THE END OF THE PERIODIC SYSTEM SO NUCLEAR PHYSICS A LA English DT Article ID BETA-STRENGTH FUNCTIONS; FISSION HALF-LIVES; SUPERHEAVY NUCLEI; HEAVIEST ELEMENTS; DROPLET MODEL; MASS FORMULA; HEAVY; BARRIERS; SHAPES; FUSION AB Recent studies of nuclear mass models show that it is essential to account for the Coulomb redistribution energy when calculating the nuclear potential energy in the heavy-element region. Results obtained by use of a mass model that includes Coulomb redistribution effects are analyzed. Q-values for alpha- and beta-decay are calculated. Half-lives for alpha-decay are estimated by use of the Viola-Seaborg systematics. For EC, beta+ decay and beta- decay, half-lives are calculated in a microscopic QRPA model. Calculated single-particle level structures in the heavy-element region are presented. These indicate possible regions of isomers that would be unusually stable with respect to spontaneous fission and alpha-decay. Finally, we discuss the implications of earlier extensive work on fission properties of nuclei in this region. C1 LOS ALAMOS NATL LAB,DIV THEORET,GRP T2,MS B243,LOS ALAMOS,NM 87545. UNIV MAINZ,INST KERNCHEM,W-6500 MAINZ,GERMANY. NR 67 TC 67 Z9 67 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD NOV 2 PY 1992 VL 549 IS 1 BP 84 EP 102 DI 10.1016/0375-9474(92)90068-U PG 19 WC Physics, Nuclear SC Physics GA JY883 UT WOS:A1992JY88300005 ER PT J AU FROGGATT, CD MOORHOUSE, RG KNOWLES, IG AF FROGGATT, CD MOORHOUSE, RG KNOWLES, IG TI 2 SCALAR DOUBLET MODELS WITH SOFTLY BROKEN SYMMETRIES SO NUCLEAR PHYSICS B LA English DT Article ID ELECTRIC-DIPOLE MOMENT; RENORMALIZATION-GROUP ANALYSIS; HIGGS-BOSON-EXCHANGE; GROUP FIXED-POINTS; RADIATIVE-CORRECTIONS; STANDARD MODEL; CP-VIOLATION; TOP QUARK; 2-HIGGS-DOUBLET MODEL; VACUUM POLARIZATION AB A generalized two scalar doublet extension of the standard model is proposed, including a soft scalar term which explicitly breaks CP invariance and the discrete symmetry protecting against scalar mediated, flavour changing neutral currents. The allowed scalar spectrum in the model is discussed together with the top quark mass, based upon the adoption of renormalization group, quasi-fixed point values for the free hard couplings in the lagrangian. The radiative corrections arising from the new scalar sector are calculated and their phenomenological consequences commented upon. In the appendices a complete set of Feynman rules for the theory is given. C1 ARGONNE NATL LAB,DIV HIGH ENERGY PHYS,ARGONNE,IL 60439. RP FROGGATT, CD (reprint author), UNIV GLASGOW,DEPT PHYS & ASTRON,GLASGOW G12 8QQ,SCOTLAND. NR 80 TC 41 Z9 41 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 NOV 2 PY 1992 VL 386 IS 1 BP 63 EP 114 DI 10.1016/0550-3213(92)90176-C PG 52 WC Physics, Particles & Fields SC Physics GA JZ621 UT WOS:A1992JZ62100004 ER PT J AU ALBRECHT, A STEBBINS, A AF ALBRECHT, A STEBBINS, A TI COSMIC STRING WITH A LIGHT MASSIVE NEUTRINO SO PHYSICAL REVIEW LETTERS LA English DT Article ID LARGE-SCALE STRUCTURE; EVOLUTION; GALAXY; WAKES AB We have estimated the power spectra of density fluctuations produced by cosmic strings with neutrino hot dark matter (HDM). Normalizing at 8h-1 Mpc [where h = H-0/(100 km/secMpc), and H-0 is the Hubble constant] we find that the spectrum has more power on small (less than or similar to 10h-1 Mpc) scales than HDM + inflation, less than cold dark matter (CDM) + inflation, and significantly less the CDM + strings. With HDM, large wakes (approximately 20h-2 Mpc) give significant contribution to the power on the galaxy scale and may give rise to large sheets of galaxies. C1 UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED,BLACKETT LAB,LONDON SW7 2BZ,ENGLAND. RP ALBRECHT, A (reprint author), FERMI NATL ACCELERATOR LAB,NASA FERMILAB ASTROPHYS CTR,BOX 500,BATAVIA,IL 60510, USA. NR 20 TC 64 Z9 64 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 NOV 2 PY 1992 VL 69 IS 18 BP 2615 EP 2618 DI 10.1103/PhysRevLett.69.2615 PG 4 WC Physics, Multidisciplinary SC Physics GA JV897 UT WOS:A1992JV89700004 ER PT J AU KOLATA, JJ ZAHAR, M SMITH, R LAMKIN, K BELBOT, M TIGHE, R SHERRILL, BM ORR, NA WINFIELD, JS WINGER, JA YENNELLO, SJ SATCHLER, GR WUOSMAA, AH AF KOLATA, JJ ZAHAR, M SMITH, R LAMKIN, K BELBOT, M TIGHE, R SHERRILL, BM ORR, NA WINFIELD, JS WINGER, JA YENNELLO, SJ SATCHLER, GR WUOSMAA, AH TI QUASI-ELASTIC SCATTERING OF LI-11 AND C-11 FROM C-12 AT 60 MEV/NUCLEON SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELASTIC-SCATTERING; CROSS-SECTIONS; NUCLEUS LI-11; LIGHT-NUCLEI AB The quasielastic scattering of the exotic "halo" nucleus Li-11 on C-12 has been studied at an energy of 60 MeV/nucleon and compared with that of the A = 11 isobar C-11. The prediction of enhanced refraction in the former system is confirmed, as is the need for very long-range absorption. No evidence is found for an Airy minimum in the far-side scattering. C1 MICHIGAN STATE UNIV,NATL SUPERCONDUCTING CYCLOTRON LAB,E LANSING,MI 48824. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. RP KOLATA, JJ (reprint author), UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556, USA. RI Sherrill, Bradley/B-4098-2009; Sherrill, Bradley/B-3378-2011; Yennello, Sherry/B-5803-2015 OI Yennello, Sherry/0000-0003-3963-5217 NR 16 TC 84 Z9 86 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 NOV 2 PY 1992 VL 69 IS 18 BP 2631 EP 2634 DI 10.1103/PhysRevLett.69.2631 PG 4 WC Physics, Multidisciplinary SC Physics GA JV897 UT WOS:A1992JV89700008 ER PT J AU FITTINGHOFF, DN BOLTON, PR CHANG, B KULANDER, KC AF FITTINGHOFF, DN BOLTON, PR CHANG, B KULANDER, KC TI OBSERVATION OF NONSEQUENTIAL DOUBLE IONIZATION OF HELIUM WITH OPTICAL TUNNELING SO PHYSICAL REVIEW LETTERS LA English DT Article ID LASERS; GASES AB We have measured the ion yields for helium ionized by 120 fs, 614 nm laser pulses for intensities near 10(16) W/cm2. We have found that for these ultrashort pulses the He+2 data exhibit a feature which saturates in parallel with the He+ signal indicating that the ionization may proceed nonsequentially. We propose a new mechanism, which can exist only in the tunneling regime, for such nonsequential ionization. RP FITTINGHOFF, DN (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 15 TC 431 Z9 434 U1 2 U2 28 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 NOV 2 PY 1992 VL 69 IS 18 BP 2642 EP 2645 DI 10.1103/PhysRevLett.69.2642 PG 4 WC Physics, Multidisciplinary SC Physics GA JV897 UT WOS:A1992JV89700011 ER PT J AU WEISS, S MYCEK, MA BIGOT, JY SCHMITTRINK, S CHEMLA, DS AF WEISS, S MYCEK, MA BIGOT, JY SCHMITTRINK, S CHEMLA, DS TI COLLECTIVE EFFECTS IN EXCITONIC FREE INDUCTION DECAY - DO SEMICONDUCTORS AND ATOMS EMIT COHERENT-LIGHT IN DIFFERENT WAYS SO PHYSICAL REVIEW LETTERS LA English DT Article ID TWO-DIMENSIONAL EXCITONS; QUANTUM-WELLS; OPTICAL-PROPERTIES; PHOTON-ECHOES; RELAXATION; EXCITATIONS; PULSES; MEDIA AB We show that the many-body interactions among excitons govern the temporal line shape of the coherent (free induction decay) emission from semiconductor quantum wells. At low exciton densities, they become the dominant contribution to the emission. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP WEISS, S (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI weiss, shimon/B-4164-2009 OI weiss, shimon/0000-0002-0720-5426 NR 22 TC 164 Z9 164 U1 0 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 NOV 2 PY 1992 VL 69 IS 18 BP 2685 EP 2688 DI 10.1103/PhysRevLett.69.2685 PG 4 WC Physics, Multidisciplinary SC Physics GA JV897 UT WOS:A1992JV89700022 ER PT J AU PACZUSKI, M BARMA, M MAJUMDAR, SN HWA, T AF PACZUSKI, M BARMA, M MAJUMDAR, SN HWA, T TI FLUCTUATIONS OF A NONEQUILIBRIUM INTERFACE SO PHYSICAL REVIEW LETTERS LA English DT Note ID GROWING INTERFACES C1 UNIV OXFORD,OXFORD OX1 3NP,ENGLAND. TATA INST FUNDAMENTAL RES,BOMBAY 400005,INDIA. HARVARD UNIV,DEPT PHYS,CAMBRIDGE,MA 02138. RP PACZUSKI, M (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. RI Hwa, Terence/J-4012-2013 OI Hwa, Terence/0000-0003-1837-6842 NR 6 TC 11 Z9 11 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 2 PY 1992 VL 69 IS 18 BP 2735 EP 2735 DI 10.1103/PhysRevLett.69.2735 PG 1 WC Physics, Multidisciplinary SC Physics GA JV897 UT WOS:A1992JV89700036 ER PT J AU BEYERMANN, WP THOMPSON, JD HUNDLEY, MF GRUNER, G AF BEYERMANN, WP THOMPSON, JD HUNDLEY, MF GRUNER, G TI LOW-TEMPERATURE SPECIFIC-HEAT OF C-60 - REPLY SO PHYSICAL REVIEW LETTERS LA English DT Note C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. UNIV CALIF LOS ANGELES,DEPT PHYS,LOS ANGELES,CA 90024. RP BEYERMANN, WP (reprint author), UNIV CALIF RIVERSIDE,DEPT PHYS,RIVERSIDE,CA 92521, USA. NR 3 TC 11 Z9 11 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 2 PY 1992 VL 69 IS 18 BP 2737 EP 2737 DI 10.1103/PhysRevLett.69.2737 PG 1 WC Physics, Multidisciplinary SC Physics GA JV897 UT WOS:A1992JV89700038 ER PT J AU COOPER, F LUCHERONI, C SHEPARD, H AF COOPER, F LUCHERONI, C SHEPARD, H TI VARIATIONAL METHOD FOR STUDYING SELF-FOCUSING IN A CLASS OF NONLINEAR SCHRODINGER-EQUATIONS SO PHYSICS LETTERS A LA English DT Article ID SINGULARITY; SYSTEM AB We discuss the use of Dirac's variational principle as applied to a class of nonlinear Schrodinger equations, i partial derivative psi/partial derivative t + del2psi + g\psi*psi\(kappa)psi = 0, in d spatial dimensions for arbitrary nonlinearity parameter kappa and for Gaussian initial data at t = 0. A Gaussian trial variational wave function is used to obtain qualitative information about blowup at finite times as a function of d and kappa. For the critical case kappad = 2 we obtain an analytic expression for the critical mass necessary for blowup as a function of d which is in good agreement with the results of numerical calculations in one and two dimensions. for the supercritical case kappad > 2 we determine the critical exponents as a function Of kappa and d. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. UNIV PERUGIA,DIPARTIMENTO FIS,I-06100 PERUGIA,ITALY. UNIV PERUGIA,SEZIONE IST NAZL FIS NUCL,I-06100 PERUGIA,ITALY. RP COOPER, F (reprint author), SANTA FE INST,1660 OLD PECOS TRAIL,SANTA FE,NM 87501, USA. NR 18 TC 7 Z9 7 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD NOV 2 PY 1992 VL 170 IS 3 BP 184 EP 188 DI 10.1016/0375-9601(92)91063-W PG 5 WC Physics, Multidisciplinary SC Physics GA JW506 UT WOS:A1992JW50600004 ER PT J AU HODEL, A KIM, SH BRUNGER, AT AF HODEL, A KIM, SH BRUNGER, AT TI MODEL BIAS IN MACROMOLECULAR CRYSTAL-STRUCTURES SO ACTA CRYSTALLOGRAPHICA SECTION A LA English DT Article ID CRYSTALLOGRAPHIC REFINEMENT; MOLECULAR-DYNAMICS; RESOLUTION STRUCTURE; RAS PROTEIN; REPLACEMENT; ERRORS; MAPS AB Reduction of model bias in macromolecular crystallography through various omit-map techniques has been investigated. The two cases studied were the p21 protein complexed with GDP at 2.25 angstrom resolution and the AN02 Fab fragment of an anti-dinitrophenyl-spin-label murine monoclonal antibody complexed with its hapten at 2.9 angstrom resolution. In the former case, the correct model was compared to a partially incorrect model consisting of an exchanged pair of beta strands along with rearrangement of the connecting loops whereas, in the latter case, the correct placement of an active-site tryptophan side chain was compared to an incorrect rotamer conformation. Partial structures were created by omission of spherical regions around the incorrect region. Omit maps without refinement of the partial structure showed a large degree of model bias. Model bias could be reduced significantly by refinement of the partial structure. Simulated-annealing refinement of the partial structure showed the best results, followed by conjugate-gradient minimization with or without prior randomization of the partial structure. To avoid compensation for missing atoms during simulated-annealing refinement of the partial structure, a suitable 'boundary' region was restrained to the starting coordinates. Model bias removal by iterative density modification was not successful in that it reduced density for both the correct and incorrect conformations. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. YALE UNIV,DEPT MOLEC BIOPHYS & BIOCHEM,NEW HAVEN,CT 06511. RP HODEL, A (reprint author), HOWARD HUGHES MED INST,NEW HAVEN,CT 06511, USA. NR 44 TC 376 Z9 377 U1 0 U2 6 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7673 J9 ACTA CRYSTALLOGR A JI Acta Crystallogr. Sect. A PD NOV 1 PY 1992 VL 48 BP 851 EP 858 DI 10.1107/S0108767392006044 PN 6 PG 8 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA JX623 UT WOS:A1992JX62300009 ER PT J AU MILLS, MJ CHRZAN, DC AF MILLS, MJ CHRZAN, DC TI DYNAMIC SIMULATION OF DISLOCATION-MOTION IN L12 ALLOYS SO ACTA METALLURGICA ET MATERIALIA LA English DT Article ID ANOMALOUS YIELD BEHAVIOR; SINGLE-CRYSTALS; FLOW-STRESS; COMPUTER-SIMULATION; SCREW DISLOCATIONS; ORDERED ALLOYS; CORE STRUCTURE; WEAK-BEAM; NI3AL; TEMPERATURE AB A dynamical simulation for the motion of an isolated superdislocation (SD) under an applied stress has been developed. The simulation incorporates the concept that cross slip from {111} planes to {010} planes can locally pin the SD. This mechanism is believed to be responsible for the remarkable increase in the yield strength with increasing temperature exhibited by several intermetallic compounds with the L1(2) crystal structure (e.g. Ni,Al). Individual pinning events occur randomly with the probability of pinning depending on the local line orientation. The resulting spatial distribution of pinning points is non-random consisting of highly pinned segments oriented near screw character linked by unpinned segments of mixed character (superkinks), similar to the configurations typically observed in post-deformation substructures. The motion of the screw portions of the SD proceeds by the lateral motion of these superkinks. The glide velocity of the SD is found to be a significant fraction of the free-flight velocity. However, fluctuations in the population of superkinks along a given SD can lead to exhaustion of motion. It is concluded that the principal effect of cross-slip-pinning is not the reduction in the SD velocity, but rather the exhaustion of the density of mobile SDs. The implications of these results with respect to the modeling of both monotonic and transient deformation in these alloys are discussed. RP MILLS, MJ (reprint author), SANDIA NATL LABS, LIVERMORE, CA 94551 USA. NR 42 TC 78 Z9 78 U1 0 U2 6 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 NOV PY 1992 VL 40 IS 11 BP 3051 EP 3064 DI 10.1016/0956-7151(92)90468-T PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA JT431 UT WOS:A1992JT43100022 ER PT J AU MALOY, SA HEUER, AH LEWANDOWSKI, JJ MITCHELL, TE AF MALOY, SA HEUER, AH LEWANDOWSKI, JJ MITCHELL, TE TI ON THE SLIP SYSTEMS IN MOSI2 SO ACTA METALLURGICA ET MATERIALIA LA English DT Article ID MOLYBDENUM DISILICIDE; DEFORMATION; CRYSTALS AB The primary and secondary slip systems in MoSi2 have been identified by studying the dislocation substructures produced by microhardness indents at temperatures up to 1000-degrees-C. Two slip systems can be activated-primary {011}[100] slip, active over the whole temperature range, and secondary {110BAR}1/2[111] slip, active above 600-degrees-C. Only four independent slip systems (in the Von Mises sense) are present, even when both slip systems operate. C1 LOS ALAMOS NATL LAB, CTR MAT SCI, LOS ALAMOS, NM 87545 USA. RP MALOY, SA (reprint author), CASE WESTERN RESERVE UNIV, DEPT MAT SCI & ENGN, 10900 EUCLID AVE, CLEVELAND, OH 44106 USA. RI Maloy, Stuart/A-8672-2009 OI Maloy, Stuart/0000-0001-8037-1319 NR 13 TC 52 Z9 53 U1 0 U2 1 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 NOV PY 1992 VL 40 IS 11 BP 3159 EP 3165 DI 10.1016/0956-7151(92)90479-X PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA JT431 UT WOS:A1992JT43100033 ER PT J AU PETOUHOFF, NL ARDELL, AJ JANKOWSKI, AF AF PETOUHOFF, NL ARDELL, AJ JANKOWSKI, AF TI MECHANICAL-BEHAVIOR OF BOTH SIDES OF AN AMORPHOUS FE78B14SI8 ALLOY RIBBON AS DETERMINED FROM MINIATURIZED DISK-BEND TESTS SO ACTA METALLURGICA ET MATERIALIA LA English DT Article ID METALLIC GLASSES; PLASTIC-DEFORMATION; FE80B20 GLASSES; FRACTURE; EMBRITTLEMENT; CU59ZR41; FLOW AB A miniaturized disk-bend test was used to examine the mechanical properties of the "air" and "wheel" sides of melt-spun ribbons, 30 mum thick, of an amorphous Fe78B14Si8 alloy. The specimens were 3 mm in diameter and were tested clamped at their perimeters. Deformation was non-linear, with the load rising to a maximum value signifying the onset of fracture, Crack propagation was accompanied by substantial elongations at lower loads. The displacement of the center of the specimen at peak load was used as a measure of its ductility. The wheel side is consistently harder, stronger and more ductile than the air side. We propose that this is due to the numerous regions of low free volume at the wheel side, produced when air is entrapped between the melt and the wheel, combined with local enrichment of boron and/or silicon in these same regions. These strong regions are interspersed with those that solidified at the most rapid rate and which have the largest free volume, highest ductility, but lowest hardness and strength. The heterogeneous distribution of free volume at the wheel side invests it with its high strength and ductility; the air side has properties between these two extremes. The role of ribbon surface topography in the initiation of fracture is also discussed. C1 LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RP PETOUHOFF, NL (reprint author), UNIV CALIF LOS ANGELES, DEPT MAT SCI & ENGN, LOS ANGELES, CA 90024 USA. NR 38 TC 10 Z9 10 U1 1 U2 10 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 NOV PY 1992 VL 40 IS 11 BP 3167 EP 3177 DI 10.1016/0956-7151(92)90480-3 PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA JT431 UT WOS:A1992JT43100034 ER PT J AU JASINSKI, J PALCZEWSKA, M KORONA, K KAMINSKA, M BOURRET, ED ELLIOT, G AF JASINSKI, J PALCZEWSKA, M KORONA, K KAMINSKA, M BOURRET, ED ELLIOT, G TI DEFECTS STUDIES IN AS GROWN AND NEUTRON-IRRADIATED PHOSPHORUS RICH GAP SO ACTA PHYSICA POLONICA A LA English DT Article; Proceedings Paper CT 21ST INTERNATIONAL SCHOOL ON PHYSICS OF SEMICONDUCTING COMPOUNDS CY MAY 22-29, 1992 CL JASZOWIEC, POLAND SP POLISH ACAD SCI, INST PHYS, WARSAW UNIV, FAC PHYS AB Semi-insulating, p- and n-type liquid encapsulated Czochralski grown phosphorus rich GaP crystals before and after neutron irradiation were studied. EPR measurements proved that the phosphorus antisite defect P(Ga) introduced by neutron irradiation was exactly the same as in as grown materials, i.e. surrounded by four substitutional phosphorus atoms. In neutron irradiated crystals EPR showed also a signal, similar to the one found in plastically deformed GaAs and GaP. The concentrations of P(Ga) and of the other defect were estimated to be of the same order of magnitude. Two absorption bands at 0.81 and 1.12 eV were found for irradiated materials. The temperature dependence of resistivity indicated hopping as the mechanism of conduction in samples irradiated with doses higher than almost-equal-to 4 x 10(16) cm-2. C1 INST ELECTR MAT TECHNOL,PL-01919 WARSAW,POLAND. HEWLETT PACKARD CO,SAN JOSE,CA 95131. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP JASINSKI, J (reprint author), UNIV WARSAW,INST EXPTL PHYS,HOZA 69,PL-00681 WARSAW,POLAND. NR 7 TC 2 Z9 2 U1 0 U2 0 PU POLISH ACAD SCIENCES INST PHYSICS PI WARSAW PA AL LOTNIKOW 32-46, 02-668 WARSAW, POLAND SN 0587-4246 J9 ACTA PHYS POL A JI Acta Phys. Pol. A PD NOV PY 1992 VL 82 IS 5 BP 829 EP 832 PG 4 WC Physics, Multidisciplinary SC Physics GA KC497 UT WOS:A1992KC49700027 ER PT J AU SIOPSIS, G DELANEY, DB JADACH, S SHIO, C WARD, BFL AF SIOPSIS, G DELANEY, DB JADACH, S SHIO, C WARD, BFL TI RADIATIVE-CORRECTIONS IN PROCESSES AT THE SSC SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT 32ND CRACOW SCHOOL OF THEORETICAL PHYSICS CY JUN 02-12, 1992 CL ZAKOPANE, POLAND ID MONTE-CARLO AB We discuss radiative corrections for interactions in the SSC environment. Based on the theory of Yennie, Frautschi and Suura, we develop appropriate Monte Carlo event generators to compute the background electromagnetic radiation. Our results indicate that multiple-photon effects must be taken into account in the study of SSC physics such as Higgs decay. C1 CERN,DIV THEORY,GENEVA 23,SWITZERLAND. INST NUCL PHYS,PL-31342 KRAKOW,POLAND. STANFORD UNIV,SLAC,STANFORD,CA 94309. RP SIOPSIS, G (reprint author), UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996, USA. RI Siopsis, George/A-9779-2008 OI Siopsis, George/0000-0002-1466-2772 NR 12 TC 1 Z9 1 U1 0 U2 0 PU POLISH ACAD SCIENCES INST PHYSICS PI WARSAW PA AL LOTNIKOW 32-46, 02-668 WARSAW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD NOV PY 1992 VL 23 IS 11 BP 1133 EP 1144 PG 12 WC Physics, Multidisciplinary SC Physics GA KJ176 UT WOS:A1992KJ17600003 ER PT J AU TAYLOR, GE HANSON, PJ AF TAYLOR, GE HANSON, PJ TI FOREST TREES AND TROPOSPHERIC OZONE - ROLE OF CANOPY DEPOSITION AND LEAF UPTAKE IN DEVELOPING EXPOSURE RESPONSE RELATIONSHIPS SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT LA English DT Article; Proceedings Paper CT INTERNATIONAL CONF ON ACIDIC DEPOSITION : ITS NATURE AND IMPACTS CY SEP, 1990 CL GLASGOW, SCOTLAND ID ATMOSPHERIC POLLUTANTS; UNITED-STATES; LEAVES; RESISTANCE; SYSTEM; SITES AB The development of ozone exposure-response relationships for forests must account for sources of variation in the atmosphere (e.g. ozone exposure dynamics) and the biosphere (i.e. ecological and physiological processes that govern pollutant transport and metabolic response). Whereas considerable effort has been devoted to atmospheric issues, the role of the biosphere is not well understood. A conceptual model is proposed to identify those ecological and physiological processes most relevant in developing exposure-response relationships for ozone, many of which are based on the uniqueness of ozone as an environmental stress.. One of the greatest sources of variation underlying exposure-response relationships is the linkage between ozone transport from the troposphere through the stomata and intercellular spaces (gas phase) to metabolic sites of action in the leaf interior (liquid phase). The tropospheric pathway approaches meters in length, whereas the path length from the leaf surface to cellular target sites is less than a millimeter, and even though the latter segment is only a small fraction of the total pathway (less than 1%), physiochemical processes therein largely dictate the pollutant's fate and subsequent effects. Unfortunately, this segment of the pathway is not well characterized. Using a combination of process-level models operating at the levels of the atmosphere-canopy interface and leaf surface/leaf interior, results are presented to indicate that ozone exposure dynamics in the leaf interior can be substantially uncoupled from that in the free troposphere and that ozone in the leaf interior is not homogeneously distributed. It is concluded that biological and chemical factors operating at the atmosphere/leaf interface are at least as important as physical exposure characteristics in the atmosphere in controlling exposure-response relationships for ozone. C1 UNIV NEVADA,DEPT RANGE WILDLIFE & FORESTRY,RENO,NV 89506. OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. UNIV NEVADA,DESERT RES INST,RENO,NV 89506. RI Hanson, Paul J./D-8069-2011 OI Hanson, Paul J./0000-0001-7293-3561 NR 38 TC 40 Z9 40 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8809 J9 AGR ECOSYST ENVIRON JI Agric. Ecosyst. Environ. PD NOV PY 1992 VL 42 IS 3-4 BP 255 EP 273 DI 10.1016/0167-8809(92)90003-T PG 19 WC Agriculture, Multidisciplinary; Ecology; Environmental Sciences SC Agriculture; Environmental Sciences & Ecology GA KA904 UT WOS:A1992KA90400003 ER PT J AU KOTHE, DB MJOLSNESS, RC AF KOTHE, DB MJOLSNESS, RC TI RIPPLE - A NEW MODEL FOR INCOMPRESSIBLE FLOWS WITH FREE SURFACES SO AIAA JOURNAL LA English DT Article AB A new free-surface flow model, RIPPLE, is summarized. RIPPLE obtains finite difference solutions for incompressible flow problems having significant surface tension forces at free surfaces of arbitrarily complex topology. The key innovation is the continuum surface force model, which represents surface tension as a localized volume force. Other features include a higher order momentum advection model, a volume-of-fluid free-surface treatment, and an efficient two-step projection solution method. RIPPLE's unique capabilities are illustrated with two example problems: low-gravity jet-induced tank flow, and the collision and coalescence of two cylindrical rods. RP KOTHE, DB (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,FLUID DYNAM GRP T3,MAIL STOP B216,LOS ALAMOS,NM 87545, USA. NR 17 TC 114 Z9 116 U1 0 U2 5 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 NOV PY 1992 VL 30 IS 11 BP 2694 EP 2700 DI 10.2514/3.11286 PG 7 WC Engineering, Aerospace SC Engineering GA JV780 UT WOS:A1992JV78000016 ER PT J AU DIGNON, J HAMEED, S AF DIGNON, J HAMEED, S TI EMISSIONS OF NITROGEN-OXIDES AND SULFUR-OXIDES FROM THE FORMER SOVIET-UNION SO AMBIO LA English DT Article C1 SUNY STONY BROOK,INST TERR & PLANETARY ATMOSPHERES,STONY BROOK,NY 11794. RP DIGNON, J (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0044-7447 J9 AMBIO JI Ambio PD NOV PY 1992 VL 21 IS 7 BP 481 EP 482 PG 2 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA KC109 UT WOS:A1992KC10900010 ER PT J AU FORD, JR TERZAGHIHOWE, M AF FORD, JR TERZAGHIHOWE, M TI CHARACTERISTICS OF MAGNETICALLY SEPARATED RAT TRACHEAL EPITHELIAL-CELL POPULATIONS SO AMERICAN JOURNAL OF PHYSIOLOGY LA English DT Article DE TARGET CELL; EPITHELIAL STEM CELL; TUMOR PROMOTER; TRACHEAL REPOPULATION ID PROMOTER 12-O-TETRADECANOYLPHORBOL-13-ACETATE; FLOW-CYTOMETRY; SUBPOPULATIONS; HISTOGENESIS; INDUCTION; LESIONS; BASAL AB A simple magnetic separation technique has been developed using lectins specific for two of the cell types found in the tracheal mucosa. The resulting populations of basal and secretory cells were examined for proliferative capacity in culture and in vivo. The basal cell fraction contains the cells that proliferate in culture and respond to 12-O-tetradecanoylphorbol-13-acetate. In addition, the basal cell fraction exhibited the highest proliferative capacity in vivo during the first few days after transplantation. Repopulation of inverted intestinal segments showed that only with suspensions containing a significant proportion of basal cells could a mucociliary lining be established. Segments receiving the same number of unsorted or predominately mucous secreting cells did not repopulate in vivo. These data support the hypothesis that the basal cell is most likely the stem cell of the tracheal epithelium. C1 OAK RIDGE NATL LAB,DIV ENVIRONM & FOREST BIOL,POB 2009,OAK RIDGE,TN 37831. UNIV TENNESSEE,OAK RIDGE GRAD SCH BIOMED SCI,OAK RIDGE,TN 37830. FU NCI NIH HHS [2R01 CA34695] NR 23 TC 12 Z9 12 U1 0 U2 1 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0002-9513 J9 AM J PHYSIOL JI Am. J. Physiol. PD NOV PY 1992 VL 263 IS 5 BP L568 EP L574 PN 1 PG 7 WC Physiology SC Physiology GA JZ778 UT WOS:A1992JZ77800090 PM 1443160 ER PT J AU RENEAU, SL RAYMOND, R HARRINGTON, CD AF RENEAU, SL RAYMOND, R HARRINGTON, CD TI ELEMENTAL RELATIONSHIPS IN ROCK VARNISH STRATIGRAPHIC LAYERS, CIMA VOLCANIC FIELD, CALIFORNIA - IMPLICATIONS FOR VARNISH DEVELOPMENT AND THE INTERPRETATION OF VARNISH CHEMISTRY SO AMERICAN JOURNAL OF SCIENCE LA English DT Article ID DESERT VARNISH; AGE-DETERMINATION; ELECTRON-PROBE; MANGANESE; FUNGI; AUSTRALIA; BACTERIA; ORIGIN; IRON AB Elemental concentrations in rock varnish collected from the Cima volcanic field in the Mojave Desert, California, were determined along 72 line profiles through 15 cross sections using scanning electron microscopy and energy dispersive X-ray analysis. The mum-scale analyses allow the recognition of elemental associations in varnish that define the primary Mn, Fe, and silicate phases that constitute the bulk of individual varnish stratigraphic layers. The analyses also allow the recognition of mum-scale variability resulting from the presence of irregularly distributed secondary components, such as detrital mineral grains. Varnish stratigraphy is primarily defined by variations in the concentrations of Mn, Fe, Si, and Al, each of which typically exceeds 5 wt percent. In general, the concentrations of Fe, Si, and Al are each negatively correlated with Mn concentration. Positive correlations of Al and Si concentration indicate that they usually exist in the same phase, probably the clay component of varnish. Weaker positive correlations of Fe and Si concentration suggest that Fe generally coexists with the clay component, possibly directly associated with the clay structure. The concentration of many minor elements in Cima varnish layers reflects the stratigraphic variations in major element composition. Ba and Ca are generally associated with Mn in Cima varnish, and K and Mg are generally associated with Si. P and Ti are often associated with Fe, but these associations are less well defined. Unusually high local concentrations of many cations, including Ca, K, Mg, Ti, Si, and Fe, probably result from the incorporation of detrital mineral grains transported onto the surface of the accreting varnish. Locally high concentrations of other cations may be related to authigentc mineralization, including frequent associations of Ba and S in discrete laminae which suggest the in situ formation of a barium sulfate mineral. The causes of the variations in elemental composition between stratigraphic layers in Cima varnish are poorly understood. Varnish stratigraphy has previously been interpreted in terms of regional paleoenvironmental fluctuations that affect the Mn:Fe ratios in accreting varnish. However, Mn:Fe ratios of the uppermost varnish at Cima are highly variable, and this ratio is thus influenced by factors other than regional environmental conditions. In addition, Mn:Fe ratios provide an incomplete description of the variability between stratigraphic layers, and concurrent use of Mn:Si and Si:Fe ratios would improve definition of stratigraphic variations in varnish composition. RP RENEAU, SL (reprint author), LOS ALAMOS NATL LAB,DIV EARTH & ENVIRONM SCI,MS D462,LOS ALAMOS,NM 87545, USA. NR 46 TC 25 Z9 25 U1 1 U2 1 PU KLINE GEOLOGY LABORATORY PI NEW HAVEN PA YALE UNIV, NEW HAVEN, CT 06520 SN 0002-9599 J9 AM J SCI JI Am. J. Sci. PD NOV PY 1992 VL 292 IS 9 BP 684 EP 723 PG 40 WC Geosciences, Multidisciplinary SC Geology GA JU870 UT WOS:A1992JU87000003 ER PT J AU JOHNSON, MB ERNST, DJ AF JOHNSON, MB ERNST, DJ TI MESON-NUCLEUS DYNAMICS SO ANNALS OF PHYSICS LA English DT Review ID DOUBLE-CHARGE-EXCHANGE; LOW-ENERGY PIONS; ELASTIC-SCATTERING; RESONANCE REGION; DELTA-(1232) RESONANCE; SURFACE FLUCTUATIONS; ISOSPIN DEPENDENCE; 3,3 RESONANCE; HOLE MODEL; BAG MODEL C1 TEXAS A&M UNIV SYST,DEPT PHYS,COLL STN,TX 77843. TEXAS A&M UNIV SYST,CTR THEORET PHYS,COLL STN,TX 77843. RP JOHNSON, MB (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 169 TC 23 Z9 23 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0003-4916 J9 ANN PHYS-NEW YORK JI Ann. Phys. PD NOV 1 PY 1992 VL 219 IS 2 BP 266 EP 327 DI 10.1016/0003-4916(92)90349-Q PG 62 WC Physics, Multidisciplinary SC Physics GA KA678 UT WOS:A1992KA67800003 ER PT J AU FELDMAN, DL AF FELDMAN, DL TI AMERICAN-INDIAN WATER RIGHTS AND THE LIMITS OF LAW - BURTON,L SO ANNALS OF THE AMERICAN ACADEMY OF POLITICAL AND SOCIAL SCIENCE LA English DT Book Review C1 UNIV TENNESSEE,KNOXVILLE,TN 37996. RP FELDMAN, DL (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 SN 0002-7162 J9 ANN AM ACAD POLIT SS JI Ann. Am. Acad. Polit. Soc. Sci. PD NOV PY 1992 VL 524 BP 223 EP 224 DI 10.1177/0002716292524001044 PG 2 WC Political Science; Social Sciences, Interdisciplinary SC Government & Law; Social Sciences - Other Topics GA JU213 UT WOS:A1992JU21300045 ER PT J AU LAMBERT, SJ AF LAMBERT, SJ TI GEOCHEMISTRY OF THE WASTE ISOLATION PILOT-PLANT (WIPP) SITE, SOUTHEASTERN NEW-MEXICO, USA SO APPLIED GEOCHEMISTRY LA English DT Article AB An extensive geochemical data base, including analyses of major and minor solutes, mineralogical studies of core samples, and isotopic studies of waters, carbonates and sulfates, has been assembled for evaporites and related rocks in the northern Delaware Basin of southeastern New Mexico. These data were compiled for the geological and hydrological characterization of the Waste Isolation Pilot Plant (WIPP), which is excavated in the evaporites of the Salado Formation. These data were evaluated in order: (1) to determine the stability of the evaporite mineralogy over geological time; (2) to compare the aqueous geochemistry with host rock mineralogy; (3) to delineate the nature and timing of water-rock interactions, such as dissolution and recrystallization; and (4) to determine the geological and climatic conditions that have governed groundwater recharge. The resulting synthesis of data and current hypotheses concerning the origin, composition and history of waters in the evaporite rocks and related units of the Delaware Basin provides a tentative conceptual model for the behavior of the water-rock system since the deposition of the evaporites in the Permian. Essential components of this model include: (1) widespread Late Triassic/Early Jurassic evaporite recrystallization; (2) accumulation of deep-basin brines isolated from meteoric recharge; (3) evaporite dissolution by meteoric waters flowing in carbonates and sulfates interbedded in the uppermost Permian section and at the basin margin; (4) lateral rather than vertical infiltration of pre-Holocene meteoric waters in the uppermost Permian section; and (5) climatic conditions presently less conducive to recharge than in the Late Pleistocene. RP LAMBERT, SJ (reprint author), SANDIA NATL LABS,DIV GEOCHEM 6233,ALBUQUERQUE,NM 87185, USA. NR 0 TC 9 Z9 9 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0883-2927 J9 APPL GEOCHEM JI Appl. Geochem. PD NOV PY 1992 VL 7 IS 6 BP 513 EP 531 DI 10.1016/0883-2927(92)90068-E PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JT892 UT WOS:A1992JT89200002 ER PT J AU ALEXOFF, DL CASATI, R FOWLER, JS WOLF, AP SHEA, C SCHLYER, DJ SHIUE, CY AF ALEXOFF, DL CASATI, R FOWLER, JS WOLF, AP SHEA, C SCHLYER, DJ SHIUE, CY TI ION CHROMATOGRAPHIC ANALYSIS OF HIGH SPECIFIC ACTIVITY (18)FDG PREPARATIONS AND DETECTION OF THE CHEMICAL IMPURITY 2-DEOXY-2-CHLORO-D-GLUCOSE SO APPLIED RADIATION AND ISOTOPES LA English DT Article ID ANION-EXCHANGE CHROMATOGRAPHY; PULSED AMPEROMETRIC DETECTION; STEREOSPECIFIC SYNTHESIS; CARBOHYDRATE ANALYSIS; SEPARATION; 2--FLUORO-2-DEOXY-D-GLUCOSE; 2-FLUORO-2-DEOXY-D-GLUCOSE; MONOSACCHARIDES; ELECTRODES; RESIN AB Because of the widespread use of 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) prepared by the "Julich" method or its variants it was decided necessary to determine the major chemical impurities present in the final product. An analytical system for quantifying FDG was developed using pulsed amperometry after separation by high-performance anion exchange chromatography. With this system a heretofore unidentified impurity, 2-deoxy-2-chloro-D-glucose (ClDG, ca 20-2000 mug; typically < 100 mug), was found in our preparation and in those from other laboratories using the "Julich" method. ClDG arises from Cl- ion displacement during the labeling procedure where Cl- ion comes from several sources, and Cl- ion displacement from the Hal used in the hydrolysis step. FDG mass was present in the same preparations at a level of ca 1-40 mug. Other major chemical constituents were glucose (ca 1-6 mg) and mannose (ca 10-18 mug). Glycerol, arising from sterilizing filters, was also detected in most preparations. Although ClDG is a chemical impurity which has not been detected previously in nca FDG preparations, its biochemical and pharmacological properties are similar to FDG and 2-deoxy-D-glucose. Thus it is unlikely that the presence of small quantities of ClDG found in typical FDG preparations (ca 100 mug) would have adverse pharmacological or toxicological consequences that would limit continued application of this radiopharmaceutical in basic and clinical studies. RP ALEXOFF, DL (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. NR 38 TC 31 Z9 32 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD NOV PY 1992 VL 43 IS 11 BP 1313 EP 1322 PG 10 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA JX496 UT WOS:A1992JX49600002 ER PT J AU ZIPPI, E KABALKA, G BIDA, G SATYAMURTHY, N WIELAND, B AF ZIPPI, E KABALKA, G BIDA, G SATYAMURTHY, N WIELAND, B TI DEUTERON IRRADIATION OF CARBONIZED POLY(STYRENE DIVINYLBENZENE) RESINS FOR THE IN-TARGET PRODUCTION OF [N-13] AMMONIA SO APPLIED RADIATION AND ISOTOPES LA English DT Article AB New polymer-based materials have been evaluated in an effort to improve nitrogen-13 production with medical cyclotrons. A series of poly(styrene/divinylbenzene) derivatives have been synthesized and then pyrolysed to yield carbonized beads. Preliminary cyclotron studies indicate that pure N-13-labelled ammonia is produced upon irradiation of these materials. C1 CTI CYCLOTRON SYST INC,BERKELEY,CA. UNIV CALIF LOS ANGELES,SCH MED,DIV NUCL MED & BIOPHYS,LOS ANGELES,CA 90024. UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. RP ZIPPI, E (reprint author), LAWRENCE BERKELEY LAB,NATL TRITIUM LABELING FACIL,BERKELEY,CA 94720, USA. NR 9 TC 7 Z9 7 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD NOV PY 1992 VL 43 IS 11 BP 1363 EP 1368 PG 6 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA JX496 UT WOS:A1992JX49600009 ER PT J AU ALARIE, JP STOKES, DL SUTHERLAND, WS EDWARDS, AC VO-DINH, T AF ALARIE, JP STOKES, DL SUTHERLAND, WS EDWARDS, AC VO-DINH, T TI INTENSIFIED CHARGE COUPLED DEVICE-BASED FIBEROPTIC MONITOR FOR RAPID REMOTE SURFACE-ENHANCED RAMAN-SCATTERING SENSING SO APPLIED SPECTROSCOPY LA English DT Article DE INTENSIFIED CHARGE COUPLED DEVICE; SURFACE-ENHANCED RAMAN; FIBEROPTIC PROBE; REMOTE SENSING ID ARRAY DETECTOR; DIODE-LASER; SPECTROSCOPY; SPECTROMETRY; SUBSTRATE; SENSOR AB This paper describes the development of an intensified charge coupled device (ICCD)-based fiber-optic monitor for remote Raman and surface-enhanced Raman (SERS) sensing. Both Raman and SERS data were obtained with the use of a fiber-optic probe design incorporating 20-m optical fibers carrying the Raman signal. Spectra were obtained in 5 milliseconds for Raman and 9 ms for SERS. The proposed system could be used for a highly sensitive portable Raman system for rapid and remote chemical sensing. C1 OAK RIDGE NATL LAB, ADV MONITORING DEV GRP, OAK RIDGE, TN 37831 USA. NR 28 TC 38 Z9 38 U1 1 U2 7 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 5320 SPECTRUM DRIVE SUITE C, FREDERICK, MD 21703 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD NOV PY 1992 VL 46 IS 11 BP 1608 EP 1612 DI 10.1366/0003702924926736 PG 5 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA JZ764 UT WOS:A1992JZ76400004 ER PT J AU DEPLANO, P DEVILLANOVA, FA FERRARO, JR ISAIA, F LIPPOLIS, V MERCURI, ML AF DEPLANO, P DEVILLANOVA, FA FERRARO, JR ISAIA, F LIPPOLIS, V MERCURI, ML TI ON THE USE OF RAMAN-SPECTROSCOPY IN THE CHARACTERIZATION OF IODINE IN CHARGE-TRANSFER COMPLEXES SO APPLIED SPECTROSCOPY LA English DT Article DE CHARGE-TRANSFER; DIIODINE; POLYIODIDES; FT-RAMAN ID MOLECULAR-STRUCTURE; CRYSTAL-STRUCTURE; DIIODINE; TRANSPORT; SOLIDS AB FT-Raman spectra of some polyiodides and of a series of D.I2 charge-transfer complexes (where D is a molecule containing the thione or selone groups as donors), all characterized by x-ray diffraction, are reported. For the adducts with the thione compounds, which can be considered weak or medium-weak complexes, an empirical linear correlation between the frequency of the nu(I-I) stretching vibrations and the d(I-I) bond distances has been found. Some polyiodides show FT-Raman spectra that are indistinguishable with respect to those displayed by the neutral complexes of weak or medium-weak strength; in such cases, the polyiodide can be regarded as a diiodine molecule, perturbed by an I(n)- (n = 1,3....) donor. Polyiodides of this type show Raman absorptions falling in the linear correlation. C1 ARGONNE NATL LAB,DIV CHEM & MAT SCI,ARGONNE,IL 60439. RP DEPLANO, P (reprint author), DIPARTIMENTO CHIM & TECNOL INORGAN & METALLORGAN,VIA OSPED 72,I-09124 CAGLIARI,ITALY. NR 17 TC 70 Z9 72 U1 0 U2 5 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD NOV PY 1992 VL 46 IS 11 BP 1625 EP 1629 DI 10.1366/0003702924926880 PG 5 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA JZ764 UT WOS:A1992JZ76400007 ER PT J AU STATON, MA EDWARDS, HM BRISBIN, IL JOANEN, T MCNEASE, L AF STATON, MA EDWARDS, HM BRISBIN, IL JOANEN, T MCNEASE, L TI THE INFLUENCE OF ENVIRONMENTAL-TEMPERATURE AND DIETARY FACTORS ON UTILIZATION OF DIETARY ENERGY AND PROTEIN IN PURIFIED DIETS BY ALLIGATORS, ALLIGATOR-MISSISSIPPIENSIS (DAUDIN) SO AQUACULTURE LA English DT Article ID AMERICAN ALLIGATOR; ASSIMILATION; DIGESTION; NUTRITION; RATES AB Alligators reared for 8 weeks on purified diets at 32-degrees-C averaged greater feed intake and body weight gain, but poorer feed efficiency ratios, than those grown at 28-degrees-C. Environmental temperature had no effect on apparent digestibility of protein (95.4%), fat (96.1%), or energy (93.5%). Both isolated soybean protein (40% of dietary protein) and com dextrin (16% of gross energy) were efficiently digested. High-solubility com dextrin was slightly, but significantly, more digestible than low-solubility com dextrin. Protein digestibility was greater when high-solubility corn dextrin was fed. Added taurine (0.1% of diet) improved body weight gain and resulted in greater fat digestibility. In a second experiment, digestibility of dietary protein and fat from purified diets were high (97.3 and 92.8%, respectively) and found to be influenced by dietary fat. Digestibility coefficients for protein, but not fat, were influenced (greater) when feces were allowed to remain in water for up to 6 h prior to collection for digestibility determinations. Digestibility of individual fatty acids varied with fat source. Stearic acid was the least digestible (77%), whereas the apparent digestibility of lauric, eicosenoic and docosapentaenoic acids was the greatest (100%). Fecal collection condition (wet vs dry) influenced the digestibility coefficients of some, but not all, fatty acids. C1 UNIV GEORGIA,DEPT POULTRY SCI,ATHENS,GA 30602. SAVANNAH RIVER ECOL LAB,AIKEN,SC 29801. LOUISIANA DEPT WILDLIFE & FISHERIES,ROCKEFELLER WILDLIFE REFUGE,GRAND CHENIER,LA. RP STATON, MA (reprint author), MAINLAND HOLDINGS PTY LTD,CROCODILE FARM,POB 196,LAE,PAPUA N GUINEA. NR 25 TC 5 Z9 5 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0044-8486 J9 AQUACULTURE JI Aquaculture PD NOV 1 PY 1992 VL 107 IS 4 BP 369 EP 381 DI 10.1016/0044-8486(92)90084-X PG 13 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA JX153 UT WOS:A1992JX15300007 ER PT J AU NEWMAN, MC AF NEWMAN, MC TI ZINC ELIMINATION KINETICS IN MOSQUITOFISH - A CLARIFICATION SO AQUATIC TOXICOLOGY LA English DT Letter ID GAMBUSIA-AFFINIS BAIRD; SIZE-DEPENDENCE; GIRARD RP NEWMAN, MC (reprint author), UNIV GEORGIA,SAVANNAH RIVER ECOL LAB,POB DRAWER E,AIKEN,SC 29801, USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-445X J9 AQUAT TOXICOL JI Aquat. Toxicol. PD NOV PY 1992 VL 24 IS 1-2 BP 153 EP 155 DI 10.1016/0166-445X(92)90022-F PG 3 WC Marine & Freshwater Biology; Toxicology SC Marine & Freshwater Biology; Toxicology GA KA679 UT WOS:A1992KA67900009 ER PT J AU GRAHAM, J WALKER, KD BERRY, M BRYAN, EF CALLAHAN, MA FAN, A FINLEY, B LYNCH, J MCKONE, T OZKAYNAK, H SEXTON, K AF GRAHAM, J WALKER, KD BERRY, M BRYAN, EF CALLAHAN, MA FAN, A FINLEY, B LYNCH, J MCKONE, T OZKAYNAK, H SEXTON, K TI ROLE OF EXPOSURE DATABASES IN RISK ASSESSMENT SO ARCHIVES OF ENVIRONMENTAL HEALTH LA English DT Article AB Risk assessments have assumed an increasingly important role in the management of risks in this country. The determination of which pollutants or public health issues are to be regulated, the degree and extent of regulation, and the priority assigned to particular problems are all areas of risk assessment that influence the country's $100 billion annual investment in environmental protection. Recent trends in public policy have brought the practice of risk assessment under greater scrutiny. As policy makers increasingly insist that specific numerical risk levels (so-called bright lines) be incorporated into regulatory decisions, the stakes for good risk assessment practice, already high, are raised even further. Enhancing the scientific basis of risk assessments was a major goal of the Workshop on Exposure Databases. In this article, we present the Risk Assessment Work Group's evaluation of the use of exposurerelated databases in risk assessment and the group's recommendations for improvement. The work group's discussion focused on the availability, suitability, and quality of data that underly exposure assessments, a critical component of risk assessment. The work group established a framework for evaluation, based on exposure scenarios typically used in regulatory decisions. The scenarios included examples from Superfund, the Clean Air Act, the Toxic Substances Control Act, and other regulatory programs. These scenarios were used to illustrate current use of exposure data, to highlight gaps in existing data sources, and to discuss how improved exposure information can improve risk assessments. The work group concluded that many of the databases available are designed for purposes that do not meet exposure and risk assessment needs. Substantial gaps exist in measurements of actual human exposure and in the data necessary to model exposures, to characterize distributions of exposure, to identify high-risk groups, and to identify possible environmental inequities in exposure. The work group, on the basis of its findings, made both short-term and longer-term recommendations for improving the collection of exposure data in the future. C1 US EPA,ENVIRONM MONITORING SYST LAB,CINCINNATI,OH 45268. US EPA,DIV EXPOSURE EVALUAT,WASHINGTON,DC 20460. US EPA,EXPOSURE ASSESSMENT GRP,WASHINGTON,DC 20460. CALIF ENVIRONM PROTECT AGCY,PESTICIDES & ENVIRONM TOXICOL SECT,BERKELEY,CA. MCLAREN HART ENVIRONM ENGN,ALAMEDA,CA. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. EXXON CHEM CO,E MILLSTONE,NJ. HARVARD UNIV,SCH PUBL HLTH,DEPT ENVIRONM HLTH,BOSTON,MA 02115. US EPA,OFF HLTH RES,WASHINGTON,DC 20460. RP GRAHAM, J (reprint author), HARVARD UNIV,SCH PUBL HLTH,CTR RISK ANAL,677 HUNTINGTON AVE,BOSTON,MA 02115, USA. NR 8 TC 21 Z9 21 U1 0 U2 1 PU HELDREF PUBLICATIONS PI WASHINGTON PA 1319 EIGHTEENTH ST NW, WASHINGTON, DC 20036-1802 SN 0003-9896 J9 ARCH ENVIRON HEALTH JI Arch. Environ. Health PD NOV-DEC PY 1992 VL 47 IS 6 BP 408 EP 420 PG 13 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA KH566 UT WOS:A1992KH56600002 PM 1485804 ER PT J AU SMITH, GS DELEON, MJ GEORGE, AE KLUGER, A VOLKOW, ND MCRAE, T GOLOMB, J FERRIS, SH REISBERG, B CIARAVINO, J LAREGINA, ME AF SMITH, GS DELEON, MJ GEORGE, AE KLUGER, A VOLKOW, ND MCRAE, T GOLOMB, J FERRIS, SH REISBERG, B CIARAVINO, J LAREGINA, ME TI TOPOGRAPHY OF CROSS-SECTIONAL AND LONGITUDINAL GLUCOSE METABOLIC DEFICITS IN ALZHEIMERS-DISEASE - PATHOPHYSIOLOGIC IMPLICATIONS SO ARCHIVES OF NEUROLOGY LA English DT Article ID POSITRON EMISSION TOMOGRAPHY; PRIMARY DEGENERATIVE DEMENTIA; GLOBAL DETERIORATION SCALE; HUMAN-BRAIN; MUSCARINIC RECEPTORS; COMPUTED-TOMOGRAPHY; ENZYME-ACTIVITIES; CEREBRAL ATROPHY; NMR-SPECTROSCOPY; INVIVO AB Positron emission tomographic studies of cerebral glucose metabolism have shown high diagnostic specificity in distinguishing among the degenerative dementias and differentiating between Alzheimer's disease (AD) and normal aging. The current investigation was undertaken to characterize the regional glucose metabolic deficits in AD, using cross-sectional and longitudinal study designs. All subjects met the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for AD (n=45) or were normal (n=20), and the AD subjects were subdivided into incipient and mild AD and moderate plus moderately severe subgroups based on the Global Deterioration Scale. The subjects underwent a non-contrast computed tomographic scan and a positron emission tomographic (PETT VI) scan. The AD subjects (n=14) and normal control subjects (n=15) received evaluations 2 to 3 years after baseline study. The brain regions that show glucose metabolic deficits cross-sectionally (temporal and parietal association areas, with lesser degrees of deficit in subcortical gray matter structures), over the stages of AD, also show further deficits longitudinally within the same AD subjects. The reduction in glucose metabolism is greater than would be expected from the degree of brain atrophy. The glucose metabolic deficits are discussed in the context of neuropathologic findings and neurotransmitter deficits in AD. C1 NYU,SCH MED,AGING & DEMENTH RES CTR,NEW YORK,NY 10016. NYU,SCH MED,DEPT RADIOL,DIV NEURORADIOL,NEW YORK,NY 10016. NYU,SCH MED,DEPT MED,DIV GERIATR,NEW YORK,NY 10016. NYU,SCH MED,DEPT NEUROL,NEW YORK,NY 10016. BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973. RP SMITH, GS (reprint author), NYU,SCH MED,DEPT PSYCHIAT,NEW BELLEVUE 12 WZ3,550 1ST AVE,NEW YORK,NY 10016, USA. FU NIA NIH HHS [1P30-AG08051]; NIMH NIH HHS [1 ROI MH 43965-04] NR 76 TC 137 Z9 138 U1 0 U2 2 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 SN 0003-9942 J9 ARCH NEUROL-CHICAGO JI Arch. Neurol. PD NOV PY 1992 VL 49 IS 11 BP 1142 EP 1150 PG 9 WC Clinical Neurology SC Neurosciences & Neurology GA JW864 UT WOS:A1992JW86400013 PM 1444881 ER PT J AU Ahlen, S Ambrosio, M Antolini, R Auriemma, G Baker, R Baldini, A Barbarino, GC Barish, BC Battistoni, G Bellotti, R Bemporad, C Bernardini, P Bilokon, H Bisi, V Bloise, C Bower, C Bussino, S Cafagna, F Calicchio, M Campana, P Campana, D Carboni, M Cecchini, S Cei, F Chiarella, V Chiera, C Cobis, A Cormack, R Corona, A Coutu, S DeCataldo, G DeMarzo, C De Vincenzi, M Di Credico, A Diehl, E Dekhissi, H Erriquez, O Favuzzi, C Ficenec, D Forti, C Foti, L Fusco, P Giacomelli, G Giannini, G Giglietto, N Giubellino, P Grassi, M Green, P Grillo, A Guarino, F Gustavino, C Habig, A Heinz, R Hong, JT Iarocci, E Katsavounidis, E Kearns, E Klein, S Kyriazopoulou, S Lamanna, E Lane, C Lee, C Levin, D Lipari, P Liu, G Liu, R Longo, MJ Ludlam, G Mancarella, G Mandrioli, G Margiotta-Neri, A Marin, A Marini, A Martello, D Martellotti, G Chiesa, AM Masera, M Matteuzzi, P Michael, DG Miller, L Monacelli, P Monteno, M Mufson, S Musser, J Nicolo, D Nutter, S Okada, C Osteria, G Palamara, O Parlati, S Patera, V Patrizii, L Pazzi, R Peck, CW Petrakis, J Petrera, S Pignatano, ND Pistilli, P Predieri, F Ramello, L Reynoldson, J Ronga, F Rosa, G Satriano, C Satta, L Scapparone, E Scholberg, K Sciubba, A Lugaresi, PS Severi, M Sitta, M Spinelli, P Spinetti, M Spurio, M Steele, J Steinberg, R Stone, JL Sulak, LR Surdo, A Tarle, G Togo, V Valente, V Verdone, GR Walter, CW Webb, R Worstell, W AF Ahlen, S. Ambrosio, M. Antolini, R. Auriemma, G. Baker, R. Baldini, A. Barbarino, G. C. Barish, B. C. Battistoni, G. Bellotti, R. Bemporad, C. Bernardini, P. Bilokon, H. Bisi, V. Bloise, C. Bower, C. Bussino, S. Cafagna, F. Calicchio, M. Campana, P. Campana, D. Carboni, M. Cecchini, S. Cei, F. Chiarella, V. Chiera, C. Cobis, A. Cormack, R. Corona, A. Coutu, S. DeCataldo, G. DeMarzo, C. De Vincenzi, M. Di Credico, A. Diehl, E. Dekhissi, H. Erriquez, O. Favuzzi, C. Ficenec, D. Forti, C. Foti, L. Fusco, P. Giacomelli, G. Giannini, G. Giglietto, N. Giubellino, P. Grassi, M. Green, P. Grillo, A. Guarino, F. Gustavino, C. Habig, A. Heinz, R. Hong, J. T. Iarocci, E. Katsavounidis, E. Kearns, E. Klein, S. Kyriazopoulou, S. Lamanna, E. Lane, C. Lee, C. Levin, D. Lipari, P. Liu, G. Liu, R. Longo, M. J. Ludlam, G. Mancarella, G. Mandrioli, G. Margiotta-Neri, A. Marin, A. Marini, A. Martello, D. Martellotti, G. Chiesa, A. Marzari Masera, M. Matteuzzi, P. Michael, D. G. Miller, L. Monacelli, P. Monteno, M. Mufson, S. Musser, J. Nicolo, D. Nutter, S. Okada, C. Osteria, G. Palamara, O. Parlati, S. Patera, V. Patrizii, L. Pazzi, R. Peck, C. W. Petrakis, J. Petrera, S. Pignatano, N. D. Pistilli, P. Predieri, F. Ramello, L. Reynoldson, J. Ronga, F. Rosa, G. Satriano, C. Satta, L. Scapparone, E. Scholberg, K. Sciubba, A. Lugaresi, P. Serra Severi, M. Sitta, M. Spinelli, P. Spinetti, M. Spurio, M. Steele, J. Steinberg, R. Stone, J. L. Sulak, L. R. Surdo, A. Tarle, G. Togo, V. Valente, V. Verdone, G. R. Walter, C. W. Webb, R. Worstell, W. CA MACRO Collaboration TI Search for neutrino bursts from collapsing stars with the MACRO detector SO ASTROPARTICLE PHYSICS LA English DT Article AB The MACRO detector has been used to perform a search for bursts of neutrinos from Galactic supernovae from October 1989 to February 1992. We did not detect any burst compatible with a stellar core collapse during this interval. With an active mass of 45 tonnes of liquid scintillator, our search extended to over 60% of the stars in the Galaxy. Both the current and planned future capabilities of MACRO to detect supernovae are described. C1 [Baker, R.; Diehl, E.; Lee, C.; Levin, D.; Longo, M. J.; Tarle, G.] Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. [Bellotti, R.; Cafagna, F.; Calicchio, M.; DeCataldo, G.; DeMarzo, C.; Erriquez, O.; Favuzzi, C.; Fusco, P.; Giglietto, N.; Spinelli, P.] Univ Bari, Dipartmento Fis, I-70126 Bari, Italy. [Bellotti, R.; Cafagna, F.; Calicchio, M.; DeCataldo, G.; DeMarzo, C.; Erriquez, O.; Favuzzi, C.; Fusco, P.; Giglietto, N.; Spinelli, P.] Ist Nazl Fis Nucl, I-70126 Bari, Italy. [Antolini, R.; Cecchini, S.; Dekhissi, H.; Giacomelli, G.; Mandrioli, G.; Margiotta-Neri, A.; Matteuzzi, P.; Patrizii, L.; Predieri, F.; Scapparone, E.; Lugaresi, P. Serra; Spurio, M.; Togo, V.] Univ Bologna, Dipartmento Fis, I-40126 Bologna, Italy. [Antolini, R.; Cecchini, S.; Dekhissi, H.; Giacomelli, G.; Mandrioli, G.; Margiotta-Neri, A.; Matteuzzi, P.; Patrizii, L.; Predieri, F.; Scapparone, E.; Lugaresi, P. Serra; Spurio, M.; Togo, V.] Ist Nazl Fis Nucl, I-40126 Bologna, Italy. [Ahlen, S.; Cormack, R.; Ficenec, D.; Kearns, E.; Klein, S.; Ludlam, G.; Marin, A.; Okada, C.; Stone, J. L.; Sulak, L. R.; Worstell, W.] Boston Univ, Dept Phys, Boston, MA 02215 USA. [Barish, B. C.; Coutu, S.; Hong, J. T.; Katsavounidis, E.; Kyriazopoulou, S.; Liu, G.; Liu, R.; Michael, D. G.; Peck, C. W.; Pignatano, N. D.; Scholberg, K.; Steele, J.; Walter, C. W.] CALTECH, Pasadena, CA 91125 USA. [Lane, C.; Steinberg, R.] Drexel Univ, Dept Phys, Philadelphia, PA 19104 USA. [Battistoni, G.; Bilokon, H.; Bloise, C.; Campana, P.; Carboni, M.; Chiarella, V.; Cobis, A.; Forti, C.; Grillo, A.; Iarocci, E.; Marini, A.; Patera, V.; Ronga, F.; Satta, L.; Spinetti, M.; Valente, V.] Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Roma, Italy. [Gustavino, C.; Parlati, S.; Reynoldson, J.] Ist Nazl Fis Nucl, Lab Nazl Gran Sasso, I-67010 Laquila, Italy. [Bower, C.; Habig, A.; Heinz, R.; Miller, L.; Mufson, S.; Musser, J.; Nutter, S.] Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. [Bower, C.; Habig, A.; Heinz, R.; Miller, L.; Mufson, S.; Musser, J.; Nutter, S.] Indiana Univ, Dept Astron, Bloomington, IN 47405 USA. [Di Credico, A.; Monacelli, P.] Univ Aquila, Dipartimento Fis, I-67100 Laquila, Italy. [Di Credico, A.; Monacelli, P.] Ist Nazl Fis Nucl, I-67100 Laquila, Italy. [Bernardini, P.; Mancarella, G.; Martello, D.; Palamara, O.; Petrera, S.; Pistilli, P.; Surdo, A.] Univ Lecce, Dipartimento Fis, I-73100 Lecce, Italy. [Bernardini, P.; Mancarella, G.; Martello, D.; Palamara, O.; Petrera, S.; Pistilli, P.; Surdo, A.] Ist Nazl Fis Nucl, I-73100 Lecce, Italy. [Ambrosio, M.; Barbarino, G. C.; Campana, D.; Guarino, F.; Osteria, G.] Univ Naples, Dipartimento Fis, I-80125 Naples, Italy. [Ambrosio, M.; Barbarino, G. C.; Campana, D.; Guarino, F.; Osteria, G.] Ist Nazl Fis Nucl, I-80125 Naples, Italy. [Baldini, A.; Bemporad, C.; Cei, F.; Giannini, G.; Grassi, M.; Nicolo, D.; Pazzi, R.] Ist Nazl Fis Nucl, I-56010 Pisa, Italy. [Baldini, A.; Bemporad, C.; Cei, F.; Giannini, G.; Grassi, M.; Nicolo, D.; Pazzi, R.] Univ Pisa, Dipartimento Fis, I-56010 Pisa, Italy. [Auriemma, G.; Bussino, S.; Chiera, C.; Corona, A.; De Vincenzi, M.; Foti, L.; Lamanna, E.; Lipari, P.; Martellotti, G.; Rosa, G.; Satriano, C.; Sciubba, A.; Severi, M.; Verdone, G. R.] Univ Rome, Dipartimento Fis, I-00185 Rome, Italy. [Auriemma, G.; Bussino, S.; Chiera, C.; Corona, A.; De Vincenzi, M.; Foti, L.; Lamanna, E.; Lipari, P.; Martellotti, G.; Rosa, G.; Satriano, C.; Sciubba, A.; Severi, M.; Verdone, G. R.] Ist Nazl Fis Nucl, I-00185 Rome, Italy. [Webb, R.] Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. [Bisi, V.; Giubellino, P.; Chiesa, A. Marzari; Masera, M.; Monteno, M.; Ramello, L.; Sitta, M.] Univ Turin, Dipartimento Fis, I-10125 Turin, Italy. [Bisi, V.; Giubellino, P.; Chiesa, A. Marzari; Masera, M.; Monteno, M.; Ramello, L.; Sitta, M.] Ist Nazl Fis Nucl, I-10125 Turin, Italy. [Petrakis, J.] Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. [Green, P.] Sandia Natl Lab, Albuquerque, NM 87185 USA. [Auriemma, G.; Satriano, C.; Verdone, G. R.] Univ Basilicata, I-85100 Potenza, Italy. [Cecchini, S.] CNR, Ist TESRE, I-40126 Bologna, Italy. [Giannini, G.] Univ Trieste, I-34100 Trieste, Italy. [Giannini, G.] Ist Nazl Fis Nucl, I-34100 Trieste, Italy. [Iarocci, E.; Satta, L.; Sciubba, A.] Univ Rome, Dipartimento Energet, I-00185 Rome, Italy. RP Longo, MJ (reprint author), Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. RI gustavino, carlo/K-4355-2015; Masera, Massimo/J-4313-2012; Ramello, Luciano/F-9357-2013; Barbarino, Giancarlo/L-2559-2015; Martello, Daniele/J-3131-2012; giglietto, nicola/I-8951-2012; Cafagna, Francesco/A-9299-2010; Cei, Fabrizio/M-8891-2016; Guarino, Fausto/I-3166-2012; OI ERRIQUEZ, Onofrio/0000-0002-9784-6568; Bellotti, Roberto/0000-0003-3198-2708; gustavino, carlo/0000-0003-3232-7027; Carboni, Massimo/0000-0003-4296-3799; Petrera, Sergio/0000-0002-6029-1255; Masera, Massimo/0000-0003-1880-5467; Coutu, Stephane/0000-0003-2923-2246; Sciubba, Adalberto/0000-0002-3301-9176; Monteno, Marco/0000-0002-3521-6333; Barbarino, Giancarlo/0000-0001-9253-3397; Martello, Daniele/0000-0003-2046-3910; giglietto, nicola/0000-0002-9021-2888; Cafagna, Francesco/0000-0002-7450-4784; Cei, Fabrizio/0000-0002-8313-3540; Guarino, Fausto/0000-0003-1427-9885; Cormack, Robert/0000-0001-5553-9984 FU US Department of Energy; US National Science Foundation; Italian National Institute for Nuclear Physics (INFN) FX We gratefully acknowledge the continuous cooperation and support of the director and staff of the Gran Sasso National Laboratory. This work was supported in part by the US Department of Energy, the US National Science Foundation, and the Italian National Institute for Nuclear Physics (INFN). NR 23 TC 21 Z9 21 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-6505 J9 ASTROPART PHYS JI Astropart Phys. PD NOV PY 1992 VL 1 IS 1 BP 11 EP 25 DI 10.1016/0927-6505(92)90005-K PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA V26DJ UT WOS:000208526000003 ER PT J AU GEHMEYR, M AF GEHMEYR, M TI ON NONLINEAR RADIAL OSCILLATIONS IN CONVECTIVE RR LYRAE STARS .1. THE MATHEMATICAL-DESCRIPTION SO ASTROPHYSICAL JOURNAL LA English DT Article DE CONVECTION; STARS, INTERIORS; STARS, OSCILLATIONS; STARS, VARIABLES, OTHER (RR LYRAE) ID STABILITY AB A set of equations for the computation of nonlinear radial oscillations in convective variable stars is proposed. It consists of the radiation hydrodynamical equations coupled with a time-dependent phenomenological model for the turbulent-convective energy transport. Some elementary properties of the latter are discussed. The set of the finite difference equations are written in an arbitrary coordinate system for each node. They are coupled to an adaptive-grid algorithm which is designed to resolve the ionization regions properly. RP GEHMEYR, M (reprint author), LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545, USA. NR 27 TC 23 Z9 23 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 NOV 1 PY 1992 VL 399 IS 1 BP 265 EP 271 DI 10.1086/171921 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV047 UT WOS:A1992JV04700026 ER PT J AU GEHMEYR, M AF GEHMEYR, M TI ON NONLINEAR RADIAL OSCILLATIONS IN CONVECTIVE RR LYRAE STARS .2. COMPARISON OF A RADIATIVE AND A CONVECTIVE MODEL SO ASTROPHYSICAL JOURNAL LA English DT Article DE CONVECTION; STARS, INTERIORS; STARS, OSCILLATIONS; STARS, VARIABLES, OTHER (RR LYRAE) AB An adaptive-grid algorithm is employed to obtain full-amplitude oscillations of a radiative and a convective RR Lyrae model that sits near the red edge. It is shown that this numerical technique is superior to the traditional one in that it is capable of computing smooth radial velocity and light curves. This success is achieved because the adaptive grid is able to detect the ionization zones and to track them during the pulsation cycles. A phenomenological model for turbulent-convective energy transport is employed. The pulsations of the RR Lyrae are computed for the radiative and the convective case. The convective and the radiative simulations are discussed for both the hydrostatic and the full-amplitude models. It is demonstrated that the phenomenon of convective overshooting leads to a secondary maximum on the branch of rising light right after the instant of minimum radius. This feature is shown to be a true signature of the hydrogen convection zone. RP GEHMEYR, M (reprint author), LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545, USA. NR 13 TC 20 Z9 20 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 NOV 1 PY 1992 VL 399 IS 1 BP 272 EP 283 DI 10.1086/171922 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV047 UT WOS:A1992JV04700027 ER PT J AU BENNETT, DP STEBBINS, A BOUCHET, FR AF BENNETT, DP STEBBINS, A BOUCHET, FR TI THE IMPLICATIONS OF THE COBE DIFFUSE MICROWAVE-RADIATION RESULTS FOR COSMIC STRINGS SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMIC STRINGS; COSMOLOGY, THEORY; DIFFUSE RADIATION; EARLY UNIVERSE; LARGE-SCALE STRUCTURE OF UNIVERSE ID LARGE-SCALE STRUCTURE; BACKGROUND-RADIATION; GLOBAL TEXTURE; EVOLUTION; FLUCTUATIONS; ANISOTROPY; NETWORKS; ORIGIN AB We compare the anisotropies in the cosmic microwave background radiation measured by the COBE experiment to those predicted by cosmic string theories. We use an analytic model for the DELTAT/T power spectrum that is based on our previous numerical simulations of strings, under the assumption that cosmic strings are the sole source of the measured anisotropy. This implies a value for the string mass per unit length, mu = 1.5 +/- 0.5 x 10(-6)c2/G. This is within the range of values required for cosmic strings to successfully seed the formation of large-scale structures in the universe. These results clearly encourage further studies of DELTAT/T and large-scale structure in the cosmic string model. C1 FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510. CNRS,INST ASTROPHYS,F-75014 PARIS,FRANCE. RP BENNETT, DP (reprint author), LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550, USA. RI Bennett, David/O-2136-2013; Bouchet, Francois/B-5202-2014; OI Bennett, David/0000-0001-8043-8413; Bouchet, Francois/0000-0002-8051-2924 NR 34 TC 72 Z9 72 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 NOV 1 PY 1992 VL 399 IS 1 BP L5 EP L8 DI 10.1086/186592 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV048 UT WOS:A1992JV04800002 ER PT J AU SKINNER, CJ TIELENS, AGGM BARLOW, MJ JUSTTANONT, K AF SKINNER, CJ TIELENS, AGGM BARLOW, MJ JUSTTANONT, K TI METHANOL ICE IN THE PROTOSTAR GL-2136 SO ASTROPHYSICAL JOURNAL LA English DT Article DE DUST, EXTINCTION; ISM, ABUNDANCES; ISM, INDIVIDUAL (GL 2136); ISM, MOLECULES ID TAURUS DARK CLOUDS; INFRARED-SPECTROSCOPY; ABSORPTION FEATURES; SOLID METHANOL; SPECTRA; DUST; CO; CHEMISTRY AB We present ground-based spectra in the 10 and 20 mum atmospheric windows of the deeply embedded protostar GL 2136. These reveal narrow absorption features at 9.7 and 8.9 mum, which we ascribe to the CO-stretch and CH3 rock (respectively) of solid methanol in grain mantles. The peak position of the 9.7 mum band implies that methanol is an important ice mantle component (i.e., CH3OH/H2O > 0.5). However, the CH3OH/H2O abundance ratio derived from the observed column densities is only 0.1. This discrepancy suggests that the solid methanol and water ice are located in independent grain components. These independent components may reflect chemical differentiation during grain mantle formation and/or partial outgassing close to the protostar. C1 LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,EXPTL ASTROPHYS LAB,LIVERMORE,CA 94550. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. UNIV LONDON UNIV COLL,DEPT PHYS & ASTRON,LONDON WC1E 6BT,ENGLAND. RI Barlow, Michael/A-5638-2009 OI Barlow, Michael/0000-0002-3875-1171 NR 24 TC 80 Z9 80 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 NOV 1 PY 1992 VL 399 IS 1 BP L79 EP L82 DI 10.1086/186611 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JV048 UT WOS:A1992JV04800021 ER PT J AU DEFONTAINE, D WOLVERTON, C AF DEFONTAINE, D WOLVERTON, C TI TOWARDS A 1ST-PRINCIPLES THERMODYNAMICS OF SOLIDS - PLENARY LECTURE SO BERICHTE DER BUNSEN-GESELLSCHAFT-PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article; Proceedings Paper CT 91ST ANNUAL MEETING OF THE DEUTSCHE-BUNSEN-GESELLSCHAFT-FUR-PHYSIKALISCHE-CHEMIE - SOLIDS : THERMODYNAMICS, STRUCTURE AND BONDING CY MAY 28-30, 1992 CL VIENNA, AUSTRIA SP DEUT BUNSEN GESELL PHYS CHEM DE CRYSTAL STRUCTURE; METALS; PHASE TRANSITIONS; THERMODYNAMICS ID CLUSTER VARIATION APPROXIMATION; ISING-MODEL; 2ND-NEIGHBOR INTERACTIONS; VARIATION FORMALISM; 1ST-NEIGHBOR; ALLOYS AB Total energy density-functional methods have made it possible to calculate, from first principles, such important properties as cohesive energies, lattice constants and elastic moduli for elemental crystals and perfectly ordered compounds. Real solids are imperfect, however, so that lattice vibrations and compositional disorder lead to entropy contributions, vibrational and configurational. When these effects are included in an appropriate manner, properties of real crystals can be computed ab initio as a function of temperature and concentration. Consequently, it is possible to obtain, virtually from the knowledge of atomic numbers alone, such basic thermodynamic properties as free energies, entropies, heats of formation, and lattice parameters for stable and metastable phases, leading, for example, to the successful computation of certain classes of phase diagrams. Recent progress in field will be reviewed. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. RP DEFONTAINE, D (reprint author), UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720, USA. RI Wolverton, Christopher/B-7542-2009 NR 27 TC 5 Z9 5 U1 0 U2 1 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 NOV PY 1992 VL 96 IS 11 BP 1503 EP 1512 PG 10 WC Chemistry, Physical SC Chemistry GA KF254 UT WOS:A1992KF25400001 ER PT J AU YAO, XQ MARKING, G FRANZEN, HF AF YAO, XQ MARKING, G FRANZEN, HF TI METAL-RICH SULFIDES OF MIXED TANTALUM AND NIOBIUM - A NEW CHEMICAL CONCEPT - PROGRESS REPORT SO BERICHTE DER BUNSEN-GESELLSCHAFT-PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article; Proceedings Paper CT 91ST ANNUAL MEETING OF THE DEUTSCHE-BUNSEN-GESELLSCHAFT-FUR-PHYSIKALISCHE-CHEMIE - SOLIDS : THERMODYNAMICS, STRUCTURE AND BONDING CY MAY 28-30, 1992 CL VIENNA, AUSTRIA SP DEUT BUNSEN GESELL PHYS CHEM DE CHEMICAL BOND; CRYSTAL STRUCTURE; METALS ID TA-NB-S; CRYSTAL-STRUCTURE; TERNARY-SYSTEM AB The structures of the metal-rich sulfides of Nb and Ta are briefly reviewed, and it is suggested that the differences between the structures containing Nb and those containing Ta indicate the possibility of novel ternary compounds. The existence of four unique compounds of this type and their structures are discussed. The interplay of first-order bonding energy and configurational entropy are shown to lead to a plausible explanation for the formation of the unsual materials. The explanation is supported with extended Huckel calculations and consideration of metal-metal interactions scaled by the Pauling bond-order equation. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP YAO, XQ (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,DOE,AMES,IA 50011, USA. NR 24 TC 37 Z9 37 U1 0 U2 3 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 NOV PY 1992 VL 96 IS 11 BP 1552 EP 1557 PG 6 WC Chemistry, Physical SC Chemistry GA KF254 UT WOS:A1992KF25400006 ER PT J AU MOHANDAS, N AF MOHANDAS, N TI MOLECULAR-BASIS FOR RED-CELL MEMBRANE VISCOELASTIC PROPERTIES SO BIOCHEMICAL SOCIETY TRANSACTIONS LA English DT Article ID HEREDITARY ELLIPTOCYTOSIS; MECHANICAL STABILITY; PROTEIN-4.1; BETA; SIALOGLYCOPROTEINS; IDENTIFICATION; SPHEROCYTOSIS; ERYTHROCYTES; DEFICIENCY; SKELETONS RP MOHANDAS, N (reprint author), LAWRENCE BERKELEY LAB,DIV LIFE SCI,MAILSTOP 74-157,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. FU NIDDK NIH HHS [DK26263, DK32094] NR 29 TC 17 Z9 17 U1 0 U2 0 PU PORTLAND PRESS PI LONDON PA 59 PORTLAND PLACE, LONDON, ENGLAND W1N 3AJ SN 0300-5127 J9 BIOCHEM SOC T JI Biochem. Soc. Trans. PD NOV PY 1992 VL 20 IS 4 BP 776 EP 782 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA KA088 UT WOS:A1992KA08800017 PM 1487062 ER PT J AU JACOBSON, SC FELINGER, A GUIOCHON, G AF JACOBSON, SC FELINGER, A GUIOCHON, G TI OPTIMIZING THE SAMPLE-SIZE AND THE REDUCED VELOCITY TO ACHIEVE MAXIMUM PRODUCTION-RATES OF ENANTIOMERS SO BIOTECHNOLOGY PROGRESS LA English DT Article ID LIQUID-CHROMATOGRAPHIC SEPARATION; PROTEIN STATIONARY PHASES; BOVINE SERUM-ALBUMIN; PREPARATIVE CHROMATOGRAPHY; BAND PROFILES; OPTIMIZATION; ELUTION; PROPAGATION; RESOLUTION; SIMULATION AB Optimum experimental conditions are predicted for the maximum production rate of D- or L-alanine, purified to a 99 % purity from a racemic mixture of their N-benzoyl derivatives by preparative chromatography on ionically immobilized bovine serum albumin. The experimental production rates and recovery yields measured under these conditions are in excellent agreement with the calculated values. These results validate the approach used for optimization of preparative liquid chromatography. C1 UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV ANALYT CHEM,OAK RIDGE,TN 37831. RI Felinger, Attila/A-1595-2008 OI Felinger, Attila/0000-0001-7130-1968 NR 28 TC 16 Z9 16 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 8756-7938 J9 BIOTECHNOL PROGR JI Biotechnol. Prog. PD NOV-DEC PY 1992 VL 8 IS 6 BP 533 EP 539 DI 10.1021/bp00018a010 PG 7 WC Biotechnology & Applied Microbiology; Food Science & Technology SC Biotechnology & Applied Microbiology; Food Science & Technology GA KB854 UT WOS:A1992KB85400010 ER PT J AU DORAN, JC BARNES, FJ COULTER, RL CRAWFORD, TL BALDOCCHI, DD BALICK, L COOK, DR COOPER, D DOBOSY, RJ DUGAS, WA FRITSCHEN, L HART, RL HIPPS, L HUBBE, JM GAO, W HICKS, R KIRKHAM, RR KUNKEL, KE MARTIN, TJ MEYERS, TP PORCH, W SHANNON, JD SHAW, WJ SWIATEK, E WHITEMAN, CD AF DORAN, JC BARNES, FJ COULTER, RL CRAWFORD, TL BALDOCCHI, DD BALICK, L COOK, DR COOPER, D DOBOSY, RJ DUGAS, WA FRITSCHEN, L HART, RL HIPPS, L HUBBE, JM GAO, W HICKS, R KIRKHAM, RR KUNKEL, KE MARTIN, TJ MEYERS, TP PORCH, W SHANNON, JD SHAW, WJ SWIATEK, E WHITEMAN, CD TI THE BOARDMAN REGIONAL FLUX EXPERIMENT SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID SURFACE FLUXES; PARAMETERIZATION; MODELS; HEAT AB A field campaign was carried out near Boardman, Oregon, to study the effects of subgrid-scale variability of sensible- and latent-heat fluxes on surface boundary-layer properties. The experiment involved three U.S. Department of Energy laboratories, one National Oceanic and Atmospheric Administration laboratory, and several universities. The experiment was conducted in a region of severe contrasts in adjacent surface types that accentuated the response of the atmosphere to variable surface forcing. Large values of sensible-heat flux and low values of latent-heat flux characterized a sagebrush steppe area; significantly smaller sensible-heat fluxes and much larger latent-heat fluxes were associated with extensive tracts of irrigated farmland to the north, east, and west of the steppe. Data were obtained from an array of surface flux stations, remote-sensing devices, an instrumented aircraft, and soil and vegetation measurements. The data will be used to address the problem of extrapolating from a limited number of local measurements to area-averaged values of fluxes suitable for use in global climate models. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87544 USA. ARGONNE NATL LAB, ARGONNE, IL 60439 USA. ATMOSPHER TURBULENCE & DIFFUS DIV, OAK RIDGE, TN USA. EG&G MEASUREMENTS INC, LAS VEGAS, NV USA. BLACKLAND RES CTR, TEXAS AGR EXPT STN, TEMPLE, TX USA. UNIV WASHINGTON, SEATTLE, WA 98195 USA. UTAH STATE UNIV, LOGAN, UT 84322 USA. ILLINOIS STATE WATER SURVEY, CHAMPAIGN, IL 61820 USA. RP DORAN, JC (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. RI Kunkel, Kenneth/C-7280-2015; Baldocchi, Dennis/A-1625-2009; Dobosy, Ronald/C-3303-2016; Meyers, Tilden/C-6633-2016 OI Kunkel, Kenneth/0000-0001-6667-7047; Baldocchi, Dennis/0000-0003-3496-4919; Dobosy, Ronald/0000-0001-8399-8774; NR 16 TC 43 Z9 43 U1 1 U2 2 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 NOV PY 1992 VL 73 IS 11 BP 1785 EP 1795 DI 10.1175/1520-0477(1992)073<1785:TBRFE>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA JZ295 UT WOS:A1992JZ29500001 ER PT J AU WULLSCHLEGER, SD NORBY, RJ AF WULLSCHLEGER, SD NORBY, RJ TI RESPIRATORY COST OF LEAF GROWTH AND MAINTENANCE IN WHITE OAK SAPLINGS EXPOSED TO ATMOSPHERIC CO2 ENRICHMENT SO CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE LA English DT Note ID TREES AB Atmospheric CO2 enrichment reportedly reduces respiration of mature leaves in a number of woody and herbaceous perennials. It has vet to be determined, however, whether these reductions reflect changes in maintenance respiration alone or whether CO2 might affect growth respiration as well. This possibility was examined in white oak (Quercus alba L.) seedlings that had been planted directly into the ground within open-top chambers and exposed to ambient, ambient + 150 muL.L-1, and ambient + 300 muL.L-1 CO2 concentrations over a 3-year period. In the spring of 1992, respiration rates were measured repeatedly during leaf expansion, and the growth and maintenance coefficients were determined using a two-component model. Specific respiration rates (mg CO2.g-1.h-1) were consistently lower for leaves of CO2 enriched saplings than for leaves of ambient-grown saplings. Partitioning these reductions in leaf respiration to either the growth or maintenance coefficients indicated a strong effect of CO2 on both components. The growth coefficient for leaves exposed to the ambient CO2 treatment was 964 Mg CO2.g-1 compared with 849 and 664 mg CO2.g-1 for leaves from the two elevated CO2 concentrations, respectively. The maintenance coefficient was similarly reduced from a control rate of 114 mg CO2.g-1 d-1 to below 65 mg CO2.g-1.d-1 for leaves exposed to CO2 enrichment. Our results quantitatively describe the magnitude by which growth and maintenance respiration are affected by CO2 enrichment and as such should provide useful information for the future modeling of this phenomenon. 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; Norby, Richard/C-1773-2012 OI Wullschleger, Stan/0000-0002-9869-0446; Norby, Richard/0000-0002-0238-9828 NR 19 TC 54 Z9 55 U1 0 U2 4 PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS PI OTTAWA PA 1200 MONTREAL ROAD, BUILDING M-55, OTTAWA, ON K1A 0R6, CANADA SN 0045-5067 J9 CAN J FOREST RES JI Can. J. For. Res.-Rev. Can. Rech. For. PD NOV PY 1992 VL 22 IS 11 BP 1717 EP 1721 DI 10.1139/x92-226 PG 5 WC Forestry SC Forestry GA KC744 UT WOS:A1992KC74400018 ER PT J AU BLUMENTHAL, RD SHARKEY, RM HAYWOOD, L NATALE, AM WONG, GY SIEGEL, JA KENNEL, SJ GOLDENBERG, DM AF BLUMENTHAL, RD SHARKEY, RM HAYWOOD, L NATALE, AM WONG, GY SIEGEL, JA KENNEL, SJ GOLDENBERG, DM TI TARGETED THERAPY OF ATHYMIC MICE BEARING GW-39 HUMAN COLONIC-CANCER MICROMETASTASES WITH I-131-LABELED MONOCLONAL-ANTIBODIES SO CANCER RESEARCH LA English DT Article ID TUMOR IMPLANTATION SITE; NUDE-MICE; CARCINOEMBRYONIC-ANTIGEN; F(AB')2 FRAGMENTS; COLORECTAL-CANCER; ANIMAL HOST; MODEL; RADIOIMMUNOTHERAPY; METASTASIS; XENOGRAFT AB The therapeutic potential of radiolabeled antibodies is usually evaluated in experimental animal models bearing s.c. xenografts. We have established a micrometastatic model of the GW-39 human colonic carcinoma in the nude mouse lung (J. Natl. Cancer Inst., 83: 627-632, 1991) and presented preliminary findings on the efficacy of a I-131-anticarcino-embryonic antigen (CEA) antibody in this model. We now extend our observations on the use of radioiodinated labeled monoclonal antibodies (MAbs) to treat multiple small tumor nodules. Biodistribution and dosimetry analysis was performed for intact and F(ab')2 of NP-4 anti-CEA IgG, Mu-9 anti-colon-specific antigen IgG, isotype-matched irrelevant anti-AFP IgG, and intact MAb 34A anti-lung endothelial IgG antibody. Comparisons were made for rad dose delivered to small s.c. tumors, normal lung, lung with tumor nodules, and isolated tumor nodules. Survival curves were generated for tumor-bearing animals treated 1, 7, or 14 days after tumor cell implantation with these antibodies using the maximal tolerated dose for intact antibodies (275 muCi) and for F(ab')2 fragments (1.2 mCi). The studies established the following observations: (a) in contrast to previous results in a bulky tumor model in hamsters, intact antibodies are more therapeutic than MAb fragments for both NP-4 and Mu-9; (b) tumor nodule size, even on the microscopic level, affects therapeutic outcome; antibodies were more effective when administered 7 days postimplantation (mean nodule diameter, 150 mum) compared with treatment 14 days postimplantation (mean nodule diameter, 750 mum); (c) administration of radioiodinated Mu-9 was exquisitely effective on single avascular tumor cells that had seeded in lung; irrelevant antibody was minimally radiotoxic; (d) as in the bulky disease model, the anti-colon-specific antigen p antibody delivers a higher rad dose than the anti-CEA antibody and is significantly more therapeutic in the micrometastasis model; (e) a higher affinity anti-CEA antibody (MN-14) recognizing the same epitope on CEA as NP-4 was equally therapeutic; (f) the use of MAb directed against the lung endothelium was not as therapeutic as a tumor-associated antibody; and (g) all tumor-associated antibodies were more efficacious than administration of the maximal tolerated dose of 5-fluorouracil and leucovorin in this human tumor-xenograft model. These results provide further support for the use of radioimmunotherapy in the handling of minimal disease, probably as part of an adjuvant treatment regimen. C1 CTR MOLEC MED & IMMUNOL,GARDEN STATE CANC CTR,1 BRUCE ST,NEWARK,NJ 07103. MEM SLOAN KETTERING CANC CTR,DIV BIOSTAT,NEW YORK,NY 10021. COOPER HOSP UNIV MED CTR,DEPT RADIAT ONCOL,CAMDEN,NJ 08103. OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. FU NCI NIH HHS [CA-39841, CA-37895]; NCRR NIH HHS [S07 RR05903-04] NR 43 TC 80 Z9 81 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 0008-5472 J9 CANCER RES JI Cancer Res. PD NOV 1 PY 1992 VL 52 IS 21 BP 6036 EP 6044 PG 9 WC Oncology SC Oncology GA JV496 UT WOS:A1992JV49600027 PM 1394228 ER PT J AU IBEANU, G HARTENSTEIN, B DUNN, WC CHANG, LY HOFMANN, E COQUERELLE, T MITRA, S KAINA, B AF IBEANU, G HARTENSTEIN, B DUNN, WC CHANG, LY HOFMANN, E COQUERELLE, T MITRA, S KAINA, B TI OVEREXPRESSION OF HUMAN DNA-REPAIR PROTEIN N-METHYLPURINE-DNA GLYCOSYLASE RESULTS IN THE INCREASED REMOVAL OF N-METHYLPURINES IN DNA WITHOUT A CONCOMITANT INCREASE IN RESISTANCE TO ALKYLATING-AGENTS IN CHINESE-HAMSTER OVARY CELLS SO CARCINOGENESIS LA English DT Article ID ESCHERICHIA-COLI; ADAPTIVE RESPONSE; 3-METHYLADENINE-DNA GLYCOSYLASE; ALKA GENE; NUCLEIC-ACIDS; ISOPROPYL-PURINES; ETHYL-PURINES; EXPRESSION; PURIFICATION; INDUCTION AB N-Alkylpurines induced in DNA by simple monofunctional alkylating agents are known to be cytotoxic and possibly indirectly mutagenic. These adducts are removed by the ubiquitous N-methylpurine-DNA glycosylase (MPG) in a multistep repair pathway. Chinese hamster ovary (CHO) cell clones expressing 2- to 16-fold enhanced levels of MPG activity were isolated from cells stably transfected with human MPG cDNA expression plasmids. The in vivo removal of 3-methyladenine and 7-methylguanine from some of these lines was analyzed and was observed to reflect their MPG levels. These cell lines did not develop increased resistance, as compared to the control, in regards to cytotoxic, mutagenic and sister chromatid exchange inducing effects of the alkylating agents that induce 3-alkyladenine and 7-alkylguanine as the major alkyl adducts in DNA. These results suggest that the MPG activity is not limiting in the multi-step repair pathway of N-alkylpurines in CHO cells. C1 NUCL RES CTR,DEPT GENET & TOXICOL,W-7500 KARLSRUHE 1,GERMANY. RP IBEANU, G (reprint author), OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831, USA. FU NCI NIH HHS [CA53791, CA31721] NR 40 TC 64 Z9 66 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 NOV PY 1992 VL 13 IS 11 BP 1989 EP 1995 DI 10.1093/carcin/13.11.1989 PG 7 WC Oncology SC Oncology GA JY125 UT WOS:A1992JY12500008 PM 1423866 ER PT J AU NELSON, JM STEVENS, RG AF NELSON, JM STEVENS, RG TI FERRITIN-IRON INCREASES KILLING OF CHINESE-HAMSTER OVARY CELLS BY X-IRRADIATION SO CELL PROLIFERATION LA English DT Article ID LIPID-PEROXIDATION; DNA DAMAGE; RADICALS; CANCER; RISK AB Stationary-phase Chinese hamster ovary cells were cultured in medium containing ferritin (approximately 19% iron by weight) added at concentrations ranging from 0 to 128 mug/ml. One set of cultures was unirradiated, and another set was exposed to 4.0 Gy of X-ray. Clonogenic cell survival was assessed in each set of cultures. In the absence of added ferritin, 4.0 Gy killed approximately 50% of the cells. In the absence of radiation, ferritin was not toxic at less than 48 mug/ml; above 48 mug/ml, toxicity increased with concentration. Apoferritin was not toxic at any concentration tested (up to 1000 mug/ml). Although 32 mug/ml ferritin, reflecting only a 3-6 fold increase in iron concentration over normal serum, was not toxic, it reduced the survival of X-irradiated cells by an additional 75%. These results indicate that a sublethal concentration of ferritin can be a potent radiosensitizer. This suggests the possibility that high body iron stores may increase susceptibility to radiation injury in humans. RP NELSON, JM (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 23 TC 12 Z9 12 U1 0 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0960-7722 J9 CELL PROLIFERAT JI Cell Prolif. PD NOV PY 1992 VL 25 IS 6 BP 579 EP 585 DI 10.1111/j.1365-2184.1992.tb01461.x PG 7 WC Cell Biology SC Cell Biology GA KA103 UT WOS:A1992KA10300005 PM 1457606 ER PT J AU MURLEY, JS GRDINA, DJ MEECHAN, PJ AF MURLEY, JS GRDINA, DJ MEECHAN, PJ TI EFFECTS OF GROWTH MEDIA ON CELL-CYCLE PROGRESSION IN CHO CELLS EXPOSED TO THE RADIOPROTECTOR WR-1065 SO CELL PROLIFERATION LA English DT Article ID V79 CELLS; RADIATION; DNA; MUTAGENICITY AB WR-1065 (2-[(aminopropyl)amino]ethanethiol) reduces cytotoxic and mutagenic effects caused by exposure of cells to radiation and chemotherapeutic drugs, but the mechanisms involved are not fully known. We have observed an accumulation of cells in G2 in WR-1065 treated Chinese hamster ovary cells grown in alpha-minimal essential medium, while others have found no cell cycle effects in WR-1065 treated Chinese hamster ovary cells grown in McCoy's 5A medium. To determine if the two types of media had an effect on cells treated with WR-1065, we examined survival and cell cycle progression. Population doubling times of 12 h were observed for cells grown in both media. Incubation of AA8 cells grown in McCoy's 5A medium with 4 mm WR-1065 30 min prior to and during irradiation with Cs-137 gamma-rays resulted in a protection factor of 2.2, in close agreement with the value of 2.0 we previously obtained for AA8 cells grown in alpha-minimal essential medium. Treatment with WR-1065 caused an alteration in the cell cycles of cells grown in both media. An increase in the G2 POPUlation and a decrease in the G1 population was observed in cells incubated up to 3 h in the presence of 4 mm WR-1065, with a redistribution of the cells throughout the cell cycle occurring following removal of the drug. These data suggest that exposure of cells to WR-1065 is the cause of perturbations in cell cycle progression, and is not affected by the type of medium the cells are grown in. C1 ARGONNE NATL LAB,DIV BIOL & MED RES,ARGONNE,IL 60439. RP MURLEY, JS (reprint author), NO ILLINOIS UNIV,DEPT BIOL SCI,DE KALB,IL 60115, USA. FU NCI NIH HHS [CA-37435]; NCRR NIH HHS [S07 RR07176] NR 15 TC 0 Z9 0 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0960-7722 J9 CELL PROLIFERAT JI Cell Prolif. PD NOV PY 1992 VL 25 IS 6 BP 643 EP 650 DI 10.1111/j.1365-2184.1992.tb01466.x PG 8 WC Cell Biology SC Cell Biology GA KA103 UT WOS:A1992KA10300010 PM 1457610 ER PT J AU MARSCH, GA JANKOWIAK, R SMALL, GJ HUGHES, NC PHILLIPS, DH AF MARSCH, GA JANKOWIAK, R SMALL, GJ HUGHES, NC PHILLIPS, DH TI EVIDENCE OF INVOLVEMENT OF MULTIPLE SITES OF METABOLISM IN THE INVIVO COVALENT BINDING OF DIBENZO[A,H]PYRENE TO DNA SO CHEMICAL RESEARCH IN TOXICOLOGY LA English DT Article ID DIOL-EPOXIDES; MOUSE SKIN; CHEMICAL CARCINOGENS; ADDUCTS; BENZOPYRENE; HYDROCARBONS; MICE AB The in vivo formation of dibenzo[a,h]pyrene-DNA adducts in mouse skin was assessed by laser-excited fluorescence spectroscopy at 77 and 4.2 K. Two adducts were identified with fluorescence origin bands at approximately 383.5 and 407.2 nm, and these were shown to possess pyrene and benzo[a]pyrene (B[a]P) chromophores, respectively. Both DNA-bound chromophores displayed considerable electron-phonon coupling and likely assume a highly base-stacked or quasi-intercalated configuration within DNA duplexes. The presence of B[a]P and pyrene aromatic systems indicates that two-electron or monooxygenation metabolism occurred on either the a or h benzo moieties (which are equivalent) in the former case, and on both these rings in the latter case. The presence of two adduct species agrees with P-32-postlabeling analysis of the DNA, which showed the presence of two major adducts in both thin-layer and high-performance liquid chromatographic separations. C1 US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. INST CANC RES,HADDOW LABS,SUTTON SM2 5NG,SURREY,ENGLAND. FU NCI NIH HHS [CA 21959] NR 30 TC 13 Z9 14 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 NOV-DEC PY 1992 VL 5 IS 6 BP 765 EP 772 DI 10.1021/tx00030a006 PG 8 WC Chemistry, Medicinal; Chemistry, Multidisciplinary; Toxicology SC Pharmacology & Pharmacy; Chemistry; Toxicology GA KB009 UT WOS:A1992KB00900007 PM 1489926 ER PT J AU DUAN, ZB HAMPDENSMITH, MJ SYLWESTER, AP AF DUAN, ZB HAMPDENSMITH, MJ SYLWESTER, AP TI ROOM-TEMPERATURE CATALYTIC-HYDROGENATION OF AROMATIC-HYDROCARBONS USING [(1,5-COD)RHH]4 AS A CATALYST PRECURSOR SO CHEMISTRY OF MATERIALS LA English DT Note ID PARTICLE-SIZE; METAL; RH C1 UNIV NEW MEXICO, DEPT CHEM, ALBUQUERQUE, NM 87131 USA. UNIV NEW MEXICO, CTR MICRO ENGINEERED CERAM, ALBUQUERQUE, NM 87131 USA. SANDIA NATL LABS, DEPT 6211, ALBUQUERQUE, NM 87185 USA. NR 17 TC 30 Z9 30 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 EI 1520-5002 J9 CHEM MATER JI Chem. Mat. PD NOV-DEC PY 1992 VL 4 IS 6 BP 1146 EP 1148 DI 10.1021/cm00024a008 PG 3 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA KA305 UT WOS:A1992KA30500008 ER PT J AU KWON, YU CORBETT, JD AF KWON, YU CORBETT, JD TI CHEMISTRY IN POLAR INTERMETALLIC COMPOUNDS - THE INTERSTITIAL CHEMISTRY OF ZR5SN3 SO CHEMISTRY OF MATERIALS LA English DT Article ID ZIRCONIUM; CLUSTERS; SYSTEMS; METALS; PHASES AB The formation of stoichiometric Zr5Sn3Z derivatives through incorporation of Z within chains of confacial zirconium octahedra in the Zr5Sn3 (Mn5Si3-type) parent has been studied principally through reactive powder sintering in the range 1000-1350-degrees-C and by X-ray diffraction means. Examples with Z = B, C, N, 0, Al, Si, P, S, Cu, Zn, Ga, Ge, Sn, As, and Se have been quantitatively synthesized and characterized as powders. Complications are noted with arc-melting methods and for Z = Fe, Co, Ni where mixed Z-Sn interstitials occur. Single crystal diffraction for Z = C, 0, and Ge and Rietveld powder refinement for Ga demonstrate how the host Zr6 cavities contract or expand to accommodate Z. The Zr5Sn3S. System at 1050-degrees-C is nonstoichiometric over the range 1 > x > approximately 0.5. Volume trends as a function of Z follow the metallic/covalent radii of Z well. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. NR 31 TC 27 Z9 27 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD NOV-DEC PY 1992 VL 4 IS 6 BP 1348 EP 1355 DI 10.1021/cm00024a040 PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA KA305 UT WOS:A1992KA30500040 ER PT J AU GRAHAM, RL WRIGHT, LL TURHOLLOW, AF AF GRAHAM, RL WRIGHT, LL TURHOLLOW, AF TI THE POTENTIAL FOR SHORT-ROTATION WOODY CROPS TO REDUCE UNITED-STATES CO-2 EMISSIONS SO CLIMATIC CHANGE LA English DT Article ID BIOMASS AB Short-rotation woody crops (SRWC) could potentially displace fossil fuels and thus mitigate CO2 buildup in the atmosphere. To determine how much fossil fuel SRWC might displace in the United States and what the associated fossil carbon savings might be, a series of assumptions must be made. These assumptions concern the net SRWC biomass yields per hectare (after losses); the amount of suitable land dedicated to SRWC production; wood conversion efficiencies to electricity or liquid fuels; the energy substitution properties of various fuels; and the amount of fossil fuel used in growing, harvesting, transporting, and converting SRWC biomass. Assuming the current climate, present production, and conversion technologies and considering a conservative estimate of the U.S. land base available for SRWC (14 x 10(6) ha), we calculate that SRWC energy could displace 33.2 to 73.1 x 10(6) Mg of fossil carbon releases, 3-6% of the current annual U.S. emissions. The carbon mitigation potential per unit of land is larger with the substitution of SRWC for coal-based electricity production than for the substitution of SRWC-derived ethanol for gasoline. Assuming current climate, predicted conversion technology advancements, an optimistic estimate of the US. land base available for SRWC (28 x 10(6) ha), and an optimistic average estimate of net SRWC yields (22.4 dry Mg/ha), we calculate that SRWC energy could displace 148 to 242 x 10(6) Mg of annual fossil fuel carbon releases. Under this scenario, the carbon mitigation potential of SRWC-based electricity production would be equivalent to about 4.4% of current global fossil fuel emissions and 20% of current US. fossil fuel emissions. C1 OAK RIDGE NATL LAB,DIV ENERGY,OAK RIDGE,TN 37831. RP GRAHAM, RL (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,OAK RIDGE,TN 37831, USA. NR 21 TC 38 Z9 38 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0165-0009 J9 CLIMATIC CHANGE JI Clim. Change PD NOV PY 1992 VL 22 IS 3 BP 223 EP 238 DI 10.1007/BF00143029 PG 16 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA JV100 UT WOS:A1992JV10000004 ER PT J AU BEL, Y JACOBSON, KB FERRE, J AF BEL, Y JACOBSON, KB FERRE, J TI A COMPARATIVE-STUDY OF DROSOPHILA PHENYLALANINE-HYDROXYLASE WITH A NATURAL AND A SYNTHETIC TETRAHYDROPTERIN AS COFACTOR SO COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY LA English DT Article ID RAT-LIVER; MELANOGASTER; ACTIVATION; ENZYME; 4-MONOOXYGENASE; PURIFICATION; MECHANISM; BRAIN AB 1. Phenylalanine hydroxylase activity has been analyzed in Drosophila melanogaster using as cofactors the natural tetrahydropteridine 5,6,7,8-tetrahydrobiopterin (H-4Bip) and the synthetic one 5,6-dimethyl-5,6,7,8-tetrahydropterin (H-4Dmp). 2. The apparent V(max) and K(M) for substrate and cofactor showed that the enzyme has two times more affinity for the substrate when H-4Bip is the cofactor in the reaction. Similarly to what was found with purified rat liver phenylalanine hydroxylase, H-4Bip was the most effective cofactor, leading to 4-5 times more activity than that obtained with H-4Dmp. 3. With the natural cofactor H-4Bip, no activation of the enzyme with Phe was necessary (in contrast to mammalian phenylalanine hydroxylase), and this tetrahydropteridine inhibits phenylalanine hydroxylase activity when the enzyme is exposed to it before phenylalanine addition. With the synthetic H-4Dmp, both types of preincubations led to an increase of phenylalanine hydroxylase activity. 4. The.enzyme is highly unstable compared to mammalian phenylalanine hydroxylase, even at - 20-degrees-C. 5. Thorax and abdomen extracts caused significant inhibition of phenylalanine hydroxylase activity from third instar larvae or newborn adult head extracts, when assayed with the synthetic cofactor H-4Dmp. This inhibition did not happen with H-4Bip. The presence of the pteridine 7-xanthopterin in adult bodies was not the cause of this inhibition. C1 UNIV VALENCIA,FAC BIOL,DEPT GENET,DR MOLINER 50,E-46100 BURJASSOT,SPAIN. OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. RI Bel, Yolanda/I-2700-2015; Ferre, Juan/L-9426-2014 OI Bel, Yolanda/0000-0002-6367-9220; Ferre, Juan/0000-0001-5535-0612 NR 40 TC 8 Z9 9 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0305-0491 J9 COMP BIOCHEM PHYS B JI Comp. Biochem. Physiol. B-Biochem. Mol. Biol. PD NOV PY 1992 VL 103 IS 3 BP 557 EP 562 DI 10.1016/0305-0491(92)90370-7 PG 6 WC Biochemistry & Molecular Biology; Zoology SC Biochemistry & Molecular Biology; Zoology GA JX537 UT WOS:A1992JX53700010 PM 1458831 ER PT J AU HSUEH, CH AF HSUEH, CH TI REQUIREMENTS OF FRICTIONAL DEBONDING AT FIBER MATRIX INTERFACES FOR TOUGH CERAMIC COMPOSITES SO COMPOSITES ENGINEERING LA English DT Article ID PULL-OUT; STRESS; STRENGTH AB Optimum toughening of fiber-reinforced ceramic composites requires debonding at fiber/matrix interfaces and subsequent frictional sliding between the fibers and the matrix as the main crack extends through the composite. Criteria of both interfacial debonding vs fiber fracture, and frictional debonding vs frictionless debonding, are illustrated. To achieve interfacial debonding, the ratio of the fiber strength to the interfacial shear strength must exceed a critical value; to achieve a frictional interface after interfacial debonding, the ratio of the interfacial residual clamping stress to the interfacial shear strength must also exceed a critical value. While interfacial debonding is not sensitive to Poisson's effect, the frictional interface is sensitive to Poisson's effect. 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 26 TC 1 Z9 1 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0961-9526 J9 COMPOS ENG JI Compos. Eng. PD NOV PY 1992 VL 2 IS 8 BP 655 EP 663 DI 10.1016/0961-9526(92)90023-Y PG 9 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA JC460 UT WOS:A1992JC46000004 ER PT J AU HSUEH, CH AF HSUEH, CH TI STRENGTH VERSUS ENERGY DEBONDING CRITERIA AT FIBER MATRIX INTERFACES SO COMPOSITES ENGINEERING LA English DT Article ID PULL-OUT STRESSES; REINFORCED COMPOSITES; BOND STRENGTH; FRACTURE AB The condition of interfacial debonding at a fiber/matrix interface has been defined by two criteria: the strength criterion, and the critical energy release rate criterion. The applied stresses required to initiate interfacial debonding during fiber pull-out or push-out are analyzed by using an improved shear-lag model, in which both Poisson's effect and the radial dependence of the axial stress in the matrix are included. Both the strength and the energy criteria are considered. The bonded fiber length dependences of the debond stresses are obtained for both criteria. For the energy criterion, the asymptote of the debond stress obtained in the present study and the length-independent debond stress derived elsewhere are in excellent agreement. The effects of the properties of the fiber and of the matrix on the debond stress are also shown for both criteria which provide a basis for experimental verification of these two criteria. 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 24 TC 3 Z9 3 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0961-9526 J9 COMPOS ENG JI Compos. Eng. PD NOV PY 1992 VL 2 IS 8 BP 665 EP 675 DI 10.1016/0961-9526(92)90024-Z PG 11 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA JC460 UT WOS:A1992JC46000005 ER PT J AU HAMEROFF, SR DAYHOFF, JE LAHOZBELTRA, R SAMSONOVICH, AV RASMUSSEN, S AF HAMEROFF, SR DAYHOFF, JE LAHOZBELTRA, R SAMSONOVICH, AV RASMUSSEN, S TI MODELS FOR MOLECULAR COMPUTATION - CONFORMATIONAL AUTOMATA IN THE CYTOSKELETON SO COMPUTER LA English DT Article C1 UNIV MARYLAND,INST SYST RES,COLL PK,MD 20742. UNIV COMPLUTENSE MADRID,FAC BIOL SCI,DEPT APPL MATH,MADRID 3,SPAIN. LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87544. LOS ALAMOS NATL LAB,DIV THEORY,LOS ALAMOS,NM 87544. SANTA FE INST,SANTA FE,CA. RP HAMEROFF, SR (reprint author), UNIV ARIZONA,ARIZONA HLTH SCI CTR,DEPT ANESTHESIOL,TUCSON,AZ 85724, USA. RI LAHOZ BELTRA, RAFAEL/K-4168-2014; Samsonovich, Alexei/M-5778-2016 OI LAHOZ BELTRA, RAFAEL/0000-0001-9250-1387; Samsonovich, Alexei/0000-0003-4788-4408 NR 7 TC 23 Z9 23 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 SN 0018-9162 J9 COMPUTER JI Computer PD NOV PY 1992 VL 25 IS 11 BP 30 EP 39 DI 10.1109/2.166406 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA JW766 UT WOS:A1992JW76600005 ER PT J AU FINK, RL ROSS, FE AF FINK, RL ROSS, FE TI FFOL AND ITS RELATIONSHIP TO THE MAN/WAN ENVIRONMENT SO COMPUTER COMMUNICATIONS LA English DT Article DE FFOL; FDDI; STANDARDS; BISDN; WIDE-BAND CHANNELS; ATM AB The FDDI Follow-On LAN (FFOL) standard is being developed as a successor to FDDI. Thus FFOL, like FDDI, must address FDDI-II Wideband Channel isochronous services in the emerging voice/video multimedia market. In addition, cost effective integration of FFOL with broadband services in the emerging MAN/WAN market is essential. This means cost-effective interfacing to both SONET/SDH transmission media and cell-based (ATM) Broadband-ISDN services. This paper addresses these issues, and makes the case for FFOL as the next generation gigabit-per-second LAN. C1 ASCON TIMEPLEX INC,WOODCLIFF LAKE,NJ. RP FINK, RL (reprint author), LAWRENCE BERKELEY LAB,CYCLOTRAN RD,MAIL STOP 50B-2258,BERKELEY,CA 94720, USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0140-3664 J9 COMPUT COMMUN JI Comput. Commun. PD NOV PY 1992 VL 15 IS 9 BP 603 EP 606 DI 10.1016/0140-3664(92)90059-N PG 4 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA JU202 UT WOS:A1992JU20200008 ER PT J AU WIENKE, BR AF WIENKE, BR TI NUMERICAL PHASE ALGORITHM FOR DECOMPRESSION COMPUTERS AND APPLICATION SO COMPUTERS IN BIOLOGY AND MEDICINE LA English DT Article DE DECOMPRESSION METERS; NUCLEATION AND BUBBLES; SEPARATED PHASE ALGORITHM; MULTIDIVING SOFTWARE ID GAS CAVITATION NUCLEI; BUBBLE FORMATION; MODEL; SICKNESS; GELATIN AB Present generation decompression computers employ a simplified algorithm, limiting dissolved gas build-up in tissue and blood according to a method proposed by Haldane 80 years ago. Such a model works well for single dives, but is usually liberal and theoretically incomplete for multiple exposures within 24 hr spans. Using the critical phase hypothesis in a bubble model, we have extended the classical model of Haldane to multi-exposures. This model is discussed, and a decomputer algorithm described for multi-diving. The focus is permissible bubble excess, not just dissolved gas per se, with phase constraints affecting all tissues, fast and slow, and requiring a systematic lowering of repetitive tissue tensions. Deep repetitive and shallow multi-day exposures are impacted most by the procedure. Within nucleation theory deeper-than-first dives are also treated. A set of multi-diving fractions, xi, accounting for micronuclei excitation and regeneration, reduced bubble elimination in repetitive activity, and coupled effects on tissue tension, are proposed, with xi representing a set of multiplicative factors (less than one) applied to critical tissue tensions for multi-exposures. These factors affect repetitive activity over short time spans, deeper-than-previous and continuous multi-day activities, compared to standard computer software, and are easily encoded into existing decompression meters, potentially extending their range and flexibility over exposure regimes. RP WIENKE, BR (reprint author), LOS ALAMOS NATL LAB,ADV COMP LAB,LOS ALAMOS,NM 87545, USA. NR 33 TC 7 Z9 7 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0010-4825 J9 COMPUT BIOL MED JI Comput. Biol. Med. PD NOV PY 1992 VL 22 IS 6 BP 389 EP 406 DI 10.1016/0010-4825(92)90039-P PG 18 WC Biology; Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Computer Science; Engineering; Mathematical & Computational Biology GA KB003 UT WOS:A1992KB00300002 PM 1458851 ER PT J AU RATHI, AK CHURCH, RL SOLANKI, RS AF RATHI, AK CHURCH, RL SOLANKI, RS TI A MACRO LEVEL ANALYSIS OF THE AIRLIFT DEPLOYMENT PROBLEM SO COMPUTERS & OPERATIONS RESEARCH LA English DT Article ID MILITARY AIRLIFT AB This paper presents mathematical models for a macro level analysis of the airlift deployment problem which involves the allocation of a limited number of aircraft towards the shipment of cargo and personnel between many origins and destinations within prescribed time windows. The problem has been modeled by three linear programming formulations in a manner such that it can be solved in a personal computer environment in a timely manner. The first and second formulations represent an explicit statement of the problem. These formulations attempt to optimally allocate strategic airlift resources towards the shipment of demand (cargo and personnel) such that the maximum amount of demand is delivered on time using preferred aircraft types. A much smaller statement of the problem is achieved in the third formulation by assuming that lateness is distributed evenly over all routes. Thus, the formulations offer a tradeoff between the degree of control to be exercised by the planner and the speed of computation. The paper presents the basic structure of these formulations along with some test results. C1 UNIV CALIF SANTA BARBARA,DEPT GEOG,SANTA BARBARA,CA 93106. RP RATHI, AK (reprint author), OAK RIDGE NATL LAB,DIV ENERGY,OAK RIDGE,TN 37831, USA. NR 17 TC 0 Z9 0 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0305-0548 J9 COMPUT OPER RES JI Comput. Oper. Res. PD NOV PY 1992 VL 19 IS 8 BP 731 EP 742 DI 10.1016/0305-0548(92)90012-T PG 12 WC Computer Science, Interdisciplinary Applications; Engineering, Industrial; Operations Research & Management Science SC Computer Science; Engineering; Operations Research & Management Science GA JG413 UT WOS:A1992JG41300003 ER PT J AU EMBID, P BAER, M AF EMBID, P BAER, M TI MATHEMATICAL-ANALYSIS OF A 2-PHASE CONTINUUM MIXTURE THEORY SO CONTINUUM MECHANICS AND THERMODYNAMICS LA English DT Article ID DETONATION TRANSITION DDT AB In this paper, we study the mathematical structure of a continuum reactive mixture model of the combustion of granular energetic materials. We obtain and classify the wave fields associated with this description. This analysis shows that this system of hyperbolic equations becomes degenerate when the relative flow is locally sonic. We derive the corresponding Riemann invariants and construct simple wave solutions. We also discuss special discontinuous solutions of the system of equations. For fixed upstream conditions, different downstream states are possible when the relative velocities exceed the speed of the sound gas. C1 SANDIA NATL LABS,DEPT FLUID & THERMAL SCI,ALBUQUERQUE,NM 87185. RP EMBID, P (reprint author), UNIV NEW MEXICO,DEPT MATH & STAT,ALBUQUERQUE,NM 87131, USA. NR 15 TC 47 Z9 48 U1 1 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0935-1175 J9 CONTINUUM MECH THERM JI Continuum Mech. Thermodyn. PD NOV PY 1992 VL 4 IS 4 BP 279 EP 312 DI 10.1007/BF01129333 PG 34 WC Thermodynamics; Mechanics SC Thermodynamics; Mechanics GA JY731 UT WOS:A1992JY73100003 ER PT J AU CHRIEN, RE DOVER, CB GAL, A AF CHRIEN, RE DOVER, CB GAL, A TI 2-NUCLEON PRODUCTION OF HYPERONS AND THE SEARCH FOR STRANGE DIBARYONS SO CZECHOSLOVAK JOURNAL OF PHYSICS LA English DT Article ID PHYSICS; MODEL AB The double charge exchange reaction He-3(K-, pi+)Xn was studied at 870 MeV/c. In the X missing mass range below the sigma-nucleon production threshold (2130 MeV/c2), events were detected which can be attributed to the two-nucleon process pp(K-, pi+)LAMBDAn. This reaction and mass range also offers good prospects for finding the I = 1/2, l = 1 (P-1(1)) spin-singlet dibaryon D(s) suggested as the lowest mass S = -1 dibaryon in the MIT Bag Model. Although the existence of the D(s) is not ruled out by the present data, there is no need to invoke such an object to account for the observed events below SIGMA production threshold. We show that the cross section level for these events is compatible with a dominant two-nucleon mechanism K- p --> pi0 LAMBDA, pi0 p --> pi+ n. We also offer an interpretation of the recent (K-, K+) data on nuclear targets from Iijima et al., which display a broad peak centered around a K+ momentum of 600 MeV/c. We find that the two-nucleon mechanism K- N --> piY, piN --> K+ Y produces cross sections which are at least an order of magnitude smaller than those observed, and we suggest that the one nucleon process K- p --> phiLAMBDA, followed by the decay phi --> K+ K-, accounts for the data. C1 HEBREW UNIV JERUSALEM,RACAH,INST PHYS,IL-91904 JERUSALEM,ISRAEL. RP CHRIEN, RE (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 31 TC 15 Z9 15 U1 0 U2 1 PU CZECHOSLOVAK JNL OF PHYSICS PI PRAGUE PA FYZIKALNI USTAV AV NA SLOVANCE 2, PRAGUE, CZECH REPUBLIC 180 40 SN 0011-4626 J9 CZECH J PHYS JI Czech. J. Phys. PD NOV PY 1992 VL 42 IS 11 BP 1089 EP 1113 DI 10.1007/BF01591396 PG 25 WC Physics, Multidisciplinary SC Physics GA KK057 UT WOS:A1992KK05700004 ER PT J AU STEINMAN, AD MULHOLLAND, PJ PALUMBO, AV DEANGELIS, DL FLUM, TE AF STEINMAN, AD MULHOLLAND, PJ PALUMBO, AV DEANGELIS, DL FLUM, TE TI LOTIC ECOSYSTEM RESPONSE TO A CHLORINE DISTURBANCE SO ECOLOGICAL APPLICATIONS LA English DT Article DE ALGAE; CHLORINE; DISTURBANCE; ECOTOXICOLOGY; ELIMIA-CLAVAEFORMIS; HERBIVORY; PERIPHYTON; RESILIENCE; RESISTANCE; SNAILS; STABILITY; STREAMS ID LIGHT-ELIMINATION DISTURBANCE; PERIPHYTON COMMUNITIES; LABORATORY STREAMS; DESERT STREAM; ALGAE; ASSEMBLAGES; RECOVERY; CHLOROPHYLL; RESILIENCE; SUCCESSION AB The influence of repeated chlorine additions on the resistance and resilience of laboratory stream ecosystems was investigated- Prior to the disturbance, four treatments were imposed on eight laboratory streams in a 2 x 2 factorial design, resulting in two replicate streams per treatment. Treatments included two circulation regimes (once-through or 98% recirculated) and two levels of grazer density (1000 individuals/m2 or 0 individuals/m2, using the snail Elimia clavaeformis). Resistance of periphyton biomass to an initial set of chlorine additions was greater in once-through than recirculated streams. Periphyton resistance following a second set of chlorine additions was greater in streams without snails compared to those with snails. This appeared to be a biomass-mediated response; the greater biomass levels in no-snail streams provided a larger buffer to the oxidizing action of chlorine. Resilience of most structural parameters and area-specific carbon-fixation rates was not influenced to a significant degree either by flow regime or snail density. Resilience of chlorophyll-specific carbon fixation and exoproteolytic activity (an index of microbial activity) was greater in recirculated streams compared to once-through streams, but only when snails were present. Over the entire experimental period (15 wk), most structural parameters and area-specific carbon fixation rates were significantly greater in (1) streams without snails compared to those with them and (2) streams with once-through circulation compared to those that were recirculated, but only for those streams with snails. Our chlorine additions appeared to have relatively little influence on snails, and snail growth over the experiment was significantly greater in once-through compared to recirculated streams. These data are consistent with other findings that total residual chlorine concentrations of < 1.0 mg/L can significantly affect periphyton structure and function. However, nutrient cycling rates appeared to be little affected by the chlorine perturbation, which allowed recirculated systems to recover faster than predicted. The findings from this study suggest that periphyton mat physiognomy and integrity strongly influence system resistance (due to buffering capacity) and resilience (because of nutrient cycling). C1 UNIV TENNESSEE,DEPT BIOL,KNOXVILLE,TN 37916. RP STEINMAN, AD (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,OAK RIDGE,TN 37831, USA. RI Palumbo, Anthony/A-4764-2011; Mulholland, Patrick/C-3142-2012; OI Palumbo, Anthony/0000-0002-1102-3975; Steinman, Alan/0000-0002-4886-4305 NR 60 TC 14 Z9 14 U1 0 U2 9 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 SN 1051-0761 J9 ECOL APPL JI Ecol. Appl. PD NOV PY 1992 VL 2 IS 4 BP 341 EP 355 DI 10.2307/1941869 PG 15 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA JV605 UT WOS:A1992JV60500002 PM 27759274 ER PT J AU MALANSON, GP WESTMAN, WE YAN, YL AF MALANSON, GP WESTMAN, WE YAN, YL TI REALIZED VERSUS FUNDAMENTAL NICHE FUNCTIONS IN A MODEL OF CHAPARRAL RESPONSE TO CLIMATIC-CHANGE SO ECOLOGICAL MODELLING LA English DT Article ID COASTAL SAGE SCRUB; SIMULATION; STRATEGIES; SUCCESSION; CALIFORNIA; DYNAMICS; FORESTS; FIRE; DISPERSAL; SHRUBS AB Simulation models are being developed and used to project the effects of global climatic change, i.e., the greenhouse effect, on the dynamics and pattern of vegetation. Many models use information about species' current ranges relative to climatic variables, i.e., their realized niche, to derive response functions. Using a simulation model for Californian chaparral, we compare the projections of vegetation using response functions representing a calculated realized niche and an assumed fundamental niche. The realized niche response functions are based on the distributions of species along gradients of annual precipitation and mean temperatures of the coldest and warmest months. Then, assuming that moderate increases in precipitation (as projected by some general circulation models for Californian chaparral) will reduce stress, we modified the functions to produce assumed fundamental niche responses. Compared to the projections based on the realized niche, use of the fundamental niche produces more continuous cover, lags in change, and different dominance following climatic change. The effects of increased precipitation per se are lasting using the realized niche responses, but only temporary using the assumed fundamental niche responses. More detailed information on actual responses is needed, but the physiological information now available would be useful only in models that would consume vast computing resources. C1 LAWRENCE BERKELEY LAB,DIV APPL SCI,BERKELEY,CA 94720. UNIV IOWA,DEPT CIVIL & ENVIRONM ENGN,IOWA CITY,IA 52242. RP MALANSON, GP (reprint author), UNIV IOWA,DEPT GEOG,IOWA CITY,IA 52242, USA. NR 38 TC 52 Z9 52 U1 4 U2 34 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3800 J9 ECOL MODEL JI Ecol. Model. PD NOV PY 1992 VL 64 IS 4 BP 261 EP 277 DI 10.1016/0304-3800(92)90026-B PG 17 WC Ecology SC Environmental Sciences & Ecology GA KA579 UT WOS:A1992KA57900001 ER PT J AU VINE, EL AF VINE, EL TI PERSISTENCE OF ENERGY SAVINGS - WHAT DO WE KNOW AND HOW CAN IT BE ENSURED SO ENERGY LA English DT Article AB This paper presents a conceptual framework for analyzing persistence of energy savings, summarizes the limited experience of what we know about persistence, provides guidance for conducting retrospective and prospective persistence studies, and suggests strategies for ensuring persistence. Because this area of research is in its infancy, unequivocal conclusions about persistence would be premature. Accordingly, this paper provides guidance for both conducting research in this area and developing policies and mechanisms to help ensure the persistence of energy savings. RP VINE, EL (reprint author), LAWRENCE BERKELEY LAB,ENERGY ANAL PROGRAM,BERKELEY,CA 94720, USA. NR 47 TC 6 Z9 6 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0360-5442 J9 ENERGY JI Energy PD NOV PY 1992 VL 17 IS 11 BP 1073 EP 1084 DI 10.1016/0360-5442(92)90024-T PG 12 WC Thermodynamics; Energy & Fuels SC Thermodynamics; Energy & Fuels GA JR048 UT WOS:A1992JR04800009 ER PT J AU DYRKACZ, GR RUSCIC, L FREDERICKS, J AF DYRKACZ, GR RUSCIC, L FREDERICKS, J TI AN INVESTIGATION INTO THE PROCESS OF CENTRIFUGAL SINK FLOAT SEPARATIONS OF MICRONIZED COALS .1. SOME INFERENCES FOR COAL MACERAL SEPARATIONS SO ENERGY & FUELS LA English DT Article ID DENSITY GRADIENT CENTRIFUGATION AB The process of maceral separation using sink/float centrifugal methods was investigated for several bituminous coals with particle sizes <10 mum. Density gradient methods were used to monitor the separations. It was found that swinging bucket rotors were the best for most work. Higher centrifugal speeds also provided more pure phase, not only because of the higher centrifugal force but also due to better packing of the pellets. Several of the media commonly used for maceral separation were also used. The best media were aqueous CsCl and Ca(NO3)2 with the nonionic surfactant, Brij-35. The separation data were compared with a simple theoretical treatment of centrifugal maceral separations. The theory was able to relate the purity of separated phases to the particle size distribution and the density distribution of the coal sample. Good qualitative agreement with the expected pattern of separation was found. One problem was a tendency of float phase material to mix into the sink phase during the centrifugation process. RP DYRKACZ, GR (reprint author), ARGONNE NATL LAB,DIV CHEM,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 33 TC 4 Z9 4 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD NOV-DEC PY 1992 VL 6 IS 6 BP 720 EP 742 DI 10.1021/ef00036a006 PG 23 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA JZ352 UT WOS:A1992JZ35200006 ER PT J AU DYRKACZ, GR RUSCIC, L AF DYRKACZ, GR RUSCIC, L TI AN INVESTIGATION INTO THE PROCESS OF CENTRIFUGAL SINK FLOAT SEPARATION OF MICRONIZED COALS .2. MULTIPLE FRACTIONATION OF SINGLE COAL SAMPLES SO ENERGY & FUELS LA English DT Article ID DENSITY GRADIENT CENTRIFUGATION; MACERAL GROUPS AB Multiple sink/float density fractionations were done on three different coal samples. Density gradient centrifugation methods were used to monitor the results of the separations. The purity of a float or sink phase was directly tied to the density distribution of the coal. The size of the density interval chosen for fractionation was shown to also be important in determining the purity. Sink fractions were consistently more impure than the float material. The main reason appeared to be unavoidable mixing of float material into the sink phase during the centrifugation cycle. However, with appropriate handling very pure maceral fractions were obtained in many cases. RP DYRKACZ, GR (reprint author), ARGONNE NATL LAB,DIV CHEM,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 11 TC 5 Z9 5 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD NOV-DEC PY 1992 VL 6 IS 6 BP 743 EP 752 DI 10.1021/ef00036a007 PG 10 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA JZ352 UT WOS:A1992JZ35200007 ER PT J AU CARLSON, GA AF CARLSON, GA TI COMPUTER-SIMULATION OF THE MOLECULAR-STRUCTURE OF BITUMINOUS COAL SO ENERGY & FUELS LA English DT Article ID ALKYLATION; MODEL AB Molecular modeling techniques have been used to study the three-dimensional structure and the energetics of the Given, Wiser, Solomon, and Shinn molecular models of bituminous coal. These studies demonstrate the importance of van der Waals (vdW) interactions and hydrogen bonding in the formation and stabilization of coal macromolecular structure. VdW interactions are responsible for most of the stabilization in these models, and a tendency for the relative importance of vdW interactions to increase with increasing rank is indicated. The strengths of vdW interactions for a series of aromatic and saturated ring molecules are determined and related to those in the coal structures. Physical densities and microporosities calculated for the simulated coal structures are in good agreement with those observed experimentally. RP CARLSON, GA (reprint author), SANDIA NATL LABS,DEPT FUEL SCI,ALBUQUERQUE,NM 87185, USA. NR 29 TC 68 Z9 75 U1 2 U2 23 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD NOV-DEC PY 1992 VL 6 IS 6 BP 771 EP 778 DI 10.1021/ef00036a012 PG 8 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA JZ352 UT WOS:A1992JZ35200012 ER PT J AU KASSIR, MK HOFMAYER, CH BANDYOPADHYAY, KK AF KASSIR, MK HOFMAYER, CH BANDYOPADHYAY, KK TI A LIMIT LOAD CRITERION TO PREDICT CRACK-GROWTH IN STAINLESS-STEEL PIPES SO ENGINEERING FRACTURE MECHANICS LA English DT Article AB In a recent test program, specimens of circumferentially cracked type 304 stainless steel pipes were subjected to dynamic cyclic loading [E. Murakami et al., in Advances in Fracture and Fatigue for the 1990s (Edited by G. Yagawa and G. M. Wilkowski), Vol. 4, pp. 115-121 (1989)]. The experimental data indicated a linear correlation between the limit load of the pipe's cross-section, assuming elastic-plastic material behavior, and the logarithm of the number of loading cycles which are required to drive the crack through the pipe's thickness. A similar criterion is postulated to investigate the crack growth behavior observed in a High Level Vibration Test (HLVT) Program performed on a large scale modified model of a pressurized water reactor primary coolant system made of an equivalent stainless material [Y. J. Park et al., Final Report, NUREG/CR-5585 (May 1991)]. The input motion in the HLVT Program induced inelastic stresses which were responsible for the crack propagation. Reasonable results are obtained in terms of the number of loading cycles required to propagate a part-through circumferential crack through the pipe's thickness. C1 BROOKHAVEN NATL LAB,DEPT NUCL ENERGY,DIV STRUCT ANAL,UPTON,NY 11973. NR 7 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0013-7944 J9 ENG FRACT MECH JI Eng. Fract. Mech. PD NOV PY 1992 VL 43 IS 5 BP 807 EP 813 DI 10.1016/0013-7944(92)90010-C PG 7 WC Mechanics SC Mechanics GA KQ839 UT WOS:A1992KQ83900010 ER PT J AU KOONER, ZS AF KOONER, ZS TI ADSORPTION OF COPPER ONTO GOETHITE IN AQUEOUS SYSTEMS SO ENVIRONMENTAL GEOLOGY AND WATER SCIENCES LA English DT Article ID WATER; CD; ZN; CU; PB; SORPTION; CADMIUM; SOILS; PB-2+; ZINC AB The adsorption of copper(II) onto goethite was studied as a function of pH, total dissolved copper concentration, surface area of goethite, and ionic strength. The adsorption of copper was similar to that of other hydrolyzable metals. A tenfold increase in goethite surface area had a significant effect on the adsorption edge, but a tenfold increase in the ionic strength of the medium did not effect the adsorption edge. The distribution coefficients increase sharply with increase in pH and ranged from 10 to 60,000 ml/g over a range of two and half pH units, depending on the goethite surface area and copper concentration. A tenfold decrease in ionic strength as well as a tenfold increase in surface area of goethite did not have any effect on the magnitude of distribution coefficients. Distribution coefficients were used to calculate the number of protons released per mole of copper adsorbed during the adsorption process. The average number of protons released per mole of copper adsorbed was estimated to be 1.40 +/- 0.10. RP KOONER, ZS (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831, USA. NR 24 TC 20 Z9 21 U1 2 U2 6 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0177-5146 J9 ENVIRON GEOL WATER S PD NOV-DEC PY 1992 VL 20 IS 3 BP 205 EP 212 DI 10.1007/BF01706163 PG 8 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA JZ827 UT WOS:A1992JZ82700006 ER PT J AU WATSON, AP GRIFFIN, GD AF WATSON, AP GRIFFIN, GD TI TOXICITY OF VESICANT AGENTS SCHEDULED FOR DESTRUCTION BY THE CHEMICAL STOCKPILE DISPOSAL PROGRAM SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Review ID MUSTARD GAS WORKERS; SULFUR MUSTARD; CANCER; NITROGEN AB The vesicant agents of the unitary chemical munitions stockpile include various formulations of sulfur mustard [bis-(2-chloroethyl) sulfide; agents H, HD and HT] and small quantities of the organic arsenical Lewisite [dichloro(2-chlorovinyl) arsine; agent L]. These agents can be dispersed in liquid, aerosol, or vapor form and are capable of producing severe chemical burns upon direct contact with tissue. Moist tissues such as the eyes, respiratory tract, and axillary areas are particularly affected. Available data summarizing acute dose response in humans and laboratory animals are summarized. Vesicant agents are also capable of generating delayed effects such as chronic bronchitis, carcinogenesis, or keratitis/keratopathy of the eye under appropriate conditions of exposure and dose. These effects may not become manifest until years following exposure. Risk analysis derived from carcinogenesis data indicates that sulfur mustard possesses a carcinogenic potency similar to that of benzo[a]pyrene. Because mustard agents are alkylating compounds, they destroy individual cells by reaction with cellular proteins, enzymes, RNA, and DNA. Once begun, tissue reaction is irreversible. Mustard agents are mutagenic; data for cellular and laboratory animal assays are presented. Reproductive effects have not been demonstrated in the offspring of laboratory rats. Acute Lewisite exposure has been implicated in cases of Bowen's disease, an intraepidermal squamous cell carcinoma. Lewisite is not known to generate reproductive or teratogenic effects. RP WATSON, AP (reprint author), OAK RIDGE NATL LAB,DIV HLTH & SAFETY RES,POB 2008,BLDG 45005,MS-6101,OAK RIDGE,TN 37831, USA. NR 112 TC 72 Z9 72 U1 0 U2 3 PU NATL INST ENVIRON HEALTH SCI PI RES TRIANGLE PK PA PO BOX 12233, RES TRIANGLE PK, NC 27709 SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD NOV PY 1992 VL 98 BP 259 EP 280 DI 10.2307/3431280 PG 22 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA KG637 UT WOS:A1992KG63700040 PM 1486858 ER PT J AU ROSE, KA SMITH, EP AF ROSE, KA SMITH, EP TI EXPERIMENTAL-DESIGN - THE NEGLECTED ASPECT OF ENVIRONMENTAL MONITORING SO ENVIRONMENTAL MANAGEMENT LA English DT Article DE ENVIRONMENTAL MONITORING; EXPERIMENTAL DESIGN ID QUALITY TIME-SERIES; WATER-QUALITY; CHESAPEAKE BAY; DETECTION LIMIT; TREND; VARIABLES; FREQUENCY; RECORDS; FIELD AB Environmental monitoring is increasing due to regulatory mandates and public concerns over the health of the environment. Much of the data appear to be being collected without explicit statement of hypotheses and with little regard for principles of experimental design. Mismatches between the monitoring design and the hypotheses of interest arise when inappropriate designs are used, hypotheses are poorly stated or change over time, and when data collected for one purpose are used for other purposes (i.e., data are used to evaluate hypotheses which the data were never intended to address). Two long-term time series on historical changes in dissolved oxygen (DO) in Chesapeake Bay are analyzed to illustrate how a mismatch between monitoring design and the hypotheses of interest can lead to analyses of low power and even contradictory conclusions. Neither time series was collected to evaluate long-term trends in DO; regression analysis results in one time series showing a downward trend in DO, whereas the other time series shows no temporal trend. The importance of experimental design considerations will increase in the future as monitoring is used to not only identify and define environmental problems but also to quantify the effectiveness of management and remedial actions taken in response to identified problems. To ensure the usefulness of the large amounts of environmental monitoring data accumulating, we need to ask more questions that relate how data are collected (the experimental design) to why data are collected (the hypotheses of interest). C1 VIRGINIA POLYTECH INST & STATE UNIV,DEPT STAT,BLACKSBURG,VA 24061. RP ROSE, KA (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,MS-6036,OAK RIDGE,TN 37831, USA. NR 41 TC 8 Z9 8 U1 2 U2 4 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0364-152X J9 ENVIRON MANAGE JI Environ. Manage. PD NOV-DEC PY 1992 VL 16 IS 6 BP 691 EP 700 DI 10.1007/BF02645659 PG 10 WC Environmental Sciences SC Environmental Sciences & Ecology GA JW337 UT WOS:A1992JW33700002 ER PT J AU LITTLE, JC DAISEY, JM NAZAROFF, WW AF LITTLE, JC DAISEY, JM NAZAROFF, WW TI TRANSPORT OF SUBSURFACE CONTAMINANTS INTO BUILDINGS SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID VOLATILE ORGANIC-COMPOUNDS; TAP WATER; SOIL; EXPOSURE; LANDFILLS; GASOLINE; VAPOR C1 UNIV CALIF BERKELEY,BERKELEY,CA 94720. RP LITTLE, JC (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. RI Little, John/B-4154-2009; Lucas, Elizabeth/E-2733-2010; Nazaroff, William/C-4106-2008 OI Nazaroff, William/0000-0001-5645-3357 NR 40 TC 68 Z9 70 U1 3 U2 11 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 NOV PY 1992 VL 26 IS 11 BP 2058 EP 2066 DI 10.1021/es00035a001 PG 9 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA JV989 UT WOS:A1992JV98900003 ER PT J AU ADAMS, SM CRUMBY, WD GREELEY, MS RYON, MG SCHILLING, EM AF ADAMS, SM CRUMBY, WD GREELEY, MS RYON, MG SCHILLING, EM TI RELATIONSHIPS BETWEEN PHYSIOLOGICAL AND FISH POPULATION RESPONSES IN A CONTAMINATED STREAM SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article; Proceedings Paper CT 17TH ANNUAL WORKSHOP ON AQUATIC TOXICITY CY NOV 05-07, 1990 CL VANCOUVER, CANADA DE CONTAMINANT STRESS; STRESS-RESPONSE RELATIONSHIPS; POPULATION EFFECTS; ECOLOGICAL SIGNIFICANCE; BIOINDICATORS ID FUNDULUS-HETEROCLITUS; AQUATIC ECOSYSTEMS; GROWTH; CYTOCHROME-P-450; INDICATORS; HEALTH; ACID AB Relationships between toxicant exposure, physiological effects, and population-level responses were investigated in redbreast sunfish (Lepomis auritus) from a stream receiving chronic inputs of mixed contaminants. Elevated levels of detoxification enzymes, which provided evidence of direct toxicant exposure, were associated with low lipid levels, histopathological damage, and reduced growth for fish at the upper three sites in the contaminated stream. Decreased fecundity, exhibited by fish at the upper site, might have been due to the reduced capacity of the liver to manufacture yolk proteins. Reduction in lipid pools due to metabolic drains might have decreased the amount of physiological useful energy needed for growth resulting in smaller age-specific sizes of fish at the upper three sites. This approach for investigating relationships between contaminant exposure, physiological effects, and population-level responses such as growth and size distributions could serve as a model for designing biomonitoring studies and for stimulating further research to improve our ability to evaluate the ecological significance of chronic contaminant stressors on aquatic ecosystems. RP ADAMS, SM (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831, USA. RI Greeley, Mark/D-2330-2016 OI Greeley, Mark/0000-0002-6088-5942 NR 34 TC 63 Z9 66 U1 1 U2 7 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 NOV PY 1992 VL 11 IS 11 BP 1549 EP 1557 DI 10.1897/1552-8618(1992)11[1549:RBPAFP]2.0.CO;2 PG 9 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA JT902 UT WOS:A1992JT90200005 ER PT J AU CONSTANTINOU, A GRDINA, D KIGUCHI, K HUBERMAN, E AF CONSTANTINOU, A GRDINA, D KIGUCHI, K HUBERMAN, E TI THE EFFECT OF TOPOISOMERASE INHIBITORS ON THE EXPRESSION OF DIFFERENTIATION MARKERS AND CELL-CYCLE PROGRESSION IN HUMAN K-562 LEUKEMIA-CELLS SO EXPERIMENTAL CELL RESEARCH LA English DT Article ID DNA STRAND BREAKAGE; HAMSTER OVARY CELLS; COLORIMETRIC ASSAY; ANTITUMOR DRUGS; MELANOMA-CELLS; P34CDC2 KINASE; II ACTIVITY; INDUCTION; PROLIFERATION; NOVOBIOCIN C1 ARGONNE NATL LAB,DIV BIOL & MED RES,9700 S CASS AVE,ARGONNE,IL 60436. OI Constantinou, Andreas/0000-0003-0365-1821 FU NCI NIH HHS [CA-37435] NR 37 TC 26 Z9 26 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 0014-4827 J9 EXP CELL RES JI Exp. Cell Res. PD NOV PY 1992 VL 203 IS 1 BP 100 EP 106 DI 10.1016/0014-4827(92)90044-9 PG 7 WC Oncology; Cell Biology SC Oncology; Cell Biology GA JW579 UT WOS:A1992JW57900013 PM 1330653 ER PT J AU MENON, MM ANDERSON, PM BAXI, CB LANGHORN, A LUXON, JL MAHDAVI, MA MIODUSZEWSKI, PK OWEN, LW SCHAFFER, MJ SCHAUBEL, KM SMITH, JP AF MENON, MM ANDERSON, PM BAXI, CB LANGHORN, A LUXON, JL MAHDAVI, MA MIODUSZEWSKI, PK OWEN, LW SCHAFFER, MJ SCHAUBEL, KM SMITH, JP TI PARTICLE EXHAUST SCHEME USING AN IN-VESSEL CRYOCONDENSATION PUMP IN THE ADVANCED DIVERTOR CONFIGURATION OF THE DIII-D TOKAMAK SO FUSION TECHNOLOGY LA English DT Article DE DIVERTOR SYSTEMS; PARTICLE EXHAUST; CRYOPUMP ID TRANSPORT AB A particle exhaust scheme using a cryocondensation pump in the advanced divertor configuration of the DIII-D tokamak is described. In this configuration, the pump is located inside a baffle chamber within the tokamak, designed to receive particles reflected off the divertor strike region. A concentric coaxial loop with forced-convection flow of two-phase helium is selected as the cryocondensation surface. The pumping configuration is optimized by Monte Carlo techniques to provide maximum exhaust efficiency while minimizing the deleterious effects of impingement of energetic plasma particles on cryogenic surfaces. Heat loading contributions from various sources on the cryogenic surfaces are estimated, based on which the cryogenic flow loop for the pump is designed. The mechanical aspects of the pump, designed to meet the many challenging requirements of operating the cryopump internal to the tokamak vacuum and in close proximity with the high-temperature plasma, are also outlined. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP MENON, MM (reprint author), GEN ATOM CO,POB 85608,SAN DIEGO,CA 92186, USA. NR 24 TC 17 Z9 17 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 NOV PY 1992 VL 22 IS 3 BP 356 EP 370 PG 15 WC Nuclear Science & Technology SC Nuclear Science & Technology GA JW582 UT WOS:A1992JW58200004 ER PT J AU ZUCMAN, J DELATTRE, O DESMAZE, C PLOUGASTEL, B JOUBERT, I MELOT, T PETER, M DEJONG, P ROULEAU, G AURIAS, A THOMAS, G AF ZUCMAN, J DELATTRE, O DESMAZE, C PLOUGASTEL, B JOUBERT, I MELOT, T PETER, M DEJONG, P ROULEAU, G AURIAS, A THOMAS, G TI CLONING AND CHARACTERIZATION OF THE EWINGS-SARCOMA AND PERIPHERAL NEUROEPITHELIOMA T(11 22) TRANSLOCATION BREAKPOINTS SO GENES CHROMOSOMES & CANCER LA English DT Article ID MYXOID CHONDROSARCOMA; MOLECULAR ANALYSIS; CHROMOSOME-22; REARRANGEMENTS; SEQUENCES; DNA AB Ewing's sarcoma (ES) and peripheral neuroepithelioma (PN) are related tumors, possibly of neural crest origin, which are cytogenetically characterized by the specific translocation t(11;22)(q24;q12). The cos5 locus, previously identified in the vicinity of the chromosome 22 breakpoint of this translocation, was shown by in situ hybridization on interphase nuclei to lie between VIIIF2 and LIF, two loci located on either side of the breakpoint and at a distance of less than 2,000 kb. The progressive expansion of this locus by chromosome walking led to the construction of a 300 kb contig, which finally crossed the breakpoint. The subsequent cloning of the two translocation junction fragments of a PN, followed by the molecular characterization of the translocation breakpoints of 20 ES and PN, showed that most chromosome 22 breakpoints are clustered within a small, 2 kb region. In contrast, the chromosome 11 breakpoints are scattered over a region of at least 40 kb. The translocation leads to the synthesis of a chimeric transcript that links sequences from chromosomes 22 and 11. Finally, no evidence was found of any specific difference in the position of ES and PN translocation breakpoints. C1 INST CURIE,GENET TUMEURS LAB,26 RUE ULM,F-75231 PARIS 05,FRANCE. INST CURIE,CNRS,URA 620,F-75231 PARIS 05,FRANCE. LAWRENCE LIVERMORE NATL LAB,CTR HUMAN GENOME,LIVERMORE,CA 94550. MCGILL UNIV,CTR RECH NEUROSCI,MONTREAL H3A 2T5,QUEBEC,CANADA. OI zucman-rossi, Jessica/0000-0002-5687-0334 NR 22 TC 233 Z9 237 U1 2 U2 5 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 1045-2257 J9 GENE CHROMOSOME CANC JI Gene Chromosomes Cancer PD NOV PY 1992 VL 5 IS 4 BP 271 EP 277 DI 10.1002/gcc.2870050402 PG 7 WC Oncology; Genetics & Heredity SC Oncology; Genetics & Heredity GA KA016 UT WOS:A1992KA01600001 PM 1283315 ER PT J AU TREIMAN, AH SUTTON, SR AF TREIMAN, AH SUTTON, SR TI PETROGENESIS OF THE ZAGAMI METEORITE - INFERENCES FROM SYNCHROTRON X-RAY (SXRF) MICROPROBE AND ELECTRON-MICROPROBE ANALYSES OF PYROXENES SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID DIFFUSION EXPERIMENTS; OLIVINE-MELT; CRYSTALLIZATION; COEFFICIENTS; PHENOCRYSTS; SHERGOTTY; DIFFERENTIATION; CLINOPYROXENES; FLUORESCENCE; ACHONDRITES AB The Zagami meteorite is a shergottite, a basalt rich in pigeonite, augite, and maskelynite glass (shocked plagioclase). It is one of the SNC meteorites, which are inferred to have formed on Mars. Major and minor element abundances in pyroxene, principally pigeonite, from newly available (UNM) samples were determined by electron microprobe; abundances of trace elements Ni, Cu, Zn, and Ga were obtained by synchrotron X-ray (SXRF) microprobe. Many pigeonite grains have normally zoned rims and reversely zoned cores, so that the most magnesian pigeonite forms rings or annuli in thin section view; in three dimensions, the most magnesian pigeonite may form tubes or hourglass shapes. The cores commonly contain magmatic inclusions. Other pigeonites have irregular or multiple magnesian regions, with magmatic inclusions among and between them. Abundances of Ni and Cr in the magnesian zones and cores are partially decoupled from abundances of other compatible (Mg) and incompatible (Fe, Ti) elements. The textures, chemical zoning, and element decouplings in the pigeonites are consistent with igneous crystal growth at moderate cooling rates, not isothermally or near equilibrium. From element partitioning and mass balance, the UNM Zagami is estimated to contain 20 +/- 5% or less cumulus pyroxene (half augite and half pigeonite), half the proportion suggested by equilibrium distribution of Fe/Mg between pigeonite and melt. This inconsistency may be resolved if all pigeonite/melt element partitioning was affected by the rapid growth of the pigeonites. The composition of the parental magma for the UNM Zagami, calculated by mass balance on bulk and pyroxene compositions, is similar to the 1170-degrees-C melt of the BMNH Zagami, not the 1140-degrees-C melt inferred as parental by other workers. The inference that the pyroxene zoning patterns reflect only magmatic events is consistent with an igneous age of 180 m.y. for Zagami. C1 UNIV CHICAGO,DEPT GEOPHYS SCI,CHICAGO,IL 60637. UNIV CHICAGO,CONSORTIUM ADV RADIAT SOURCES,CHICAGO,IL 60637. BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973. RP TREIMAN, AH (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,SN21,HOUSTON,TX 77058, USA. NR 67 TC 39 Z9 39 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD NOV PY 1992 VL 56 IS 11 BP 4059 EP 4074 DI 10.1016/0016-7037(92)90016-C PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JW846 UT WOS:A1992JW84600015 ER PT J AU ANTHONY, EY POTHS, J AF ANTHONY, EY POTHS, J TI HE-3 SURFACE EXPOSURE DATING AND ITS IMPLICATIONS FOR MAGMA EVOLUTION IN THE POTRILLO VOLCANIC FIELD, RIO-GRANDE RIFT, NEW-MEXICO, USA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Letter ID COSMOGENIC HE-3; KILBOURNE-HOLE; SUMMIT LAVAS; HELIUM; CHRONOLOGY; BENEATH; SOILS; MAUI AB Dating of very young igneous activity has been hampered by lack of suitable chronometers. We report here the results of He-3 surface exposure dating (KURZ, 1986a,b; CRAIG and POREDA, 1986) for lavas from the Potrillo volcanic field. This field is particularly suited to the technique because it has well-preserved, young (<700 ka) surfaces. The study applies He-3 dating in a systematic manner to a well-characterized volcanic field and shows the power of the technique in deciphering both relative and absolute chronologies. Dates are reproducible to within 14% for different samples from the same surface and are similar to within 8% for samples which, based on field relations, represent synchronous events. Cosmogenic He-3/Ne-21 confirms that He-3 is retained by the samples. Comparison of the relative chronology with compositional trends of the lavas suggests that eruptive centers within the volcanic field are fed by individual magma chambers. Ages range from 80 ka to 17 ka, consistent with estimates from geomorphology, soil profile development, and some K/Ar determinations. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP ANTHONY, EY (reprint author), UNIV TEXAS,DEPT GEOL SCI,EL PASO,TX 79968, USA. NR 22 TC 26 Z9 26 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD NOV PY 1992 VL 56 IS 11 BP 4105 EP 4108 DI 10.1016/0016-7037(92)90022-B PG 4 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JW846 UT WOS:A1992JW84600021 ER PT J AU MASPLA, J YEH, TCJ MCCARTHY, JF WILLIAMS, TM AF MASPLA, J YEH, TCJ MCCARTHY, JF WILLIAMS, TM TI A FORCED GRADIENT TRACER EXPERIMENT IN A COASTAL SANDY AQUIFER, GEORGETOWN SITE, SOUTH-CAROLINA SO GROUND WATER LA English DT Article ID STRATIFIED AQUIFERS; TESTS; DISPERSION; TRANSPORT AB A two-well tracer experiment was conducted in a coastal, sandy aquifer in South Carolina to investigate tracer migration in ground-water systems. Chloride tracer was injected into the aquifer under a steady flow condition created by continuous injection and withdrawal of ground water at an injection and a withdrawal well dipole separated by a distance of 5 meters. Breakthrough data were collected at several depths from two multilevel sampling wells, 1.5 meters apart, between the injection well and the withdrawal well. A one-dimensional advection-dispersion model that considers the nonuniform velocity field of the two-well experiment was employed to estimate the hydrologic properties of the aquifer. The values of the porosity and dispersivity were estimated by fitting the model to the observed breakthrough data collected at three depths at one sampling well (Well A). These values were then used to predict the breakthroughs at the same depths in the other sampling well (Well B). A two-dimensional flow and transport model was also employed to simulate the tracer migration. Results of both one- and two-dimensional simulations show that these models fail to predict the tracer breakthrough at Well B using parameter values obtained from Well A. The failure of the model to predict breakthroughs at Well B suggests that a three-dimensional characterization of aquifer heterogeneities and a three-dimensional modeling effort may be needed in order to capture the complex flow pattern in the aquifer. C1 OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. CLEMSON UNIV,BARUCH FOREST SCI INST,GEORGETOWN,SC 29440. RP MASPLA, J (reprint author), UNIV ARIZONA,DEPT HYDROL & WATER RESOURCES,TUCSON,AZ 85721, USA. OI Mas-Pla, Josep/0000-0002-8491-9895 NR 15 TC 22 Z9 22 U1 0 U2 11 PU GROUND WATER PUBLISHING CO PI WESTERVILLE PA 601 DEMPSEY RD, WESTERVILLE, OH 43081 SN 0017-467X J9 GROUND WATER JI Ground Water PD NOV-DEC PY 1992 VL 30 IS 6 BP 958 EP 964 DI 10.1111/j.1745-6584.1992.tb01579.x PG 7 WC Geosciences, Multidisciplinary; Water Resources SC Geology; Water Resources GA JW813 UT WOS:A1992JW81300016 ER PT J AU RHOADES, WA CHILDS, RL INGERSOLL, DT AF RHOADES, WA CHILDS, RL INGERSOLL, DT TI RADIATION EXPOSURE INSIDE REINFORCED-CONCRETE BUILDINGS AT NAGASAKI SO HEALTH PHYSICS LA English DT Article DE ATOMIC BOMB SURVIVORS; DOSIMETRY; RADIATION EFFECTS; NAGASAKI AB In this study, the radiation doses to occupants of two reinforced concrete buildings at Nagasaki, who survived the immediate effects of the nuclear weapon detonation, are determined using state-of-the-art radiation transport techniques. The radiation doses at all locations in the buildings are calculated using the Three-Dimensional Oak Ridge Discrete Ordinates Radiation Transport Code which was constructed especially for this task. This code represents a new and unique capability that has been previously reported. This study resulted in case-by-case lists of doses to occupants and an uncertainty analysis. These data have been used in a companion study as the basis for determining a new value of the dose producing a 50% risk of fatality. C1 OAK RIDGE NATL LAB, DIV COMP & TELECOMMUN, OAK RIDGE, TN 37831 USA. RP RHOADES, WA (reprint author), OAK RIDGE NATL LAB, DIV ENGN PHYS & MATH, POB 2008, BLDG 6025, MS-6363, OAK RIDGE, TN 37831 USA. NR 14 TC 5 Z9 5 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD NOV PY 1992 VL 63 IS 5 BP 510 EP 521 DI 10.1097/00004032-199211000-00002 PG 12 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA JU480 UT WOS:A1992JU48000009 PM 1399637 ER PT J AU HOPKE, PK STRYDOM, R RAMAMURTHI, M KNUTSON, EO TU, KW SCOFIELD, P HOLUB, RF CHENG, YS SU, YF WINKLMAYR, W STRONG, JC SOLOMON, S REINEKING, A AF HOPKE, PK STRYDOM, R RAMAMURTHI, M KNUTSON, EO TU, KW SCOFIELD, P HOLUB, RF CHENG, YS SU, YF WINKLMAYR, W STRONG, JC SOLOMON, S REINEKING, A TI THE MEASUREMENT OF ACTIVITY-WEIGHTED SIZE DISTRIBUTIONS OF RADON PROGENY - METHODS AND LABORATORY INTERCOMPARISON STUDIES SO HEALTH PHYSICS LA English DT Article DE RADON PROGENY; ACTIVITY-WEIGHTED SIZE DISTRIBUTIONS; AEROSOLS; RADON ID DIFFUSION BATTERY; INITIAL BEHAVIOR; WIRE SCREENS; INDOOR AIR; AEROSOL; RADIOLYSIS; DAUGHTERS; RECONSTRUCTION; POLONIUM-218; FRACTION AB Over the past 5 y, there have been significant improvements in measurement of activity-weighted size distributions of airborne radon decay products. The modification of screen diffusion batteries to incorporate multiple screens of differing mesh number, called graded screen arrays, have permitted improved size resolution below 10 nm such that the size distributions can now be determined down to molecular sized activities (0.5 nm). In order to ascertain the utility and reliability of such systems, several intercomparison tests have been performed in a 2.4 m3 radon chamber in which particles of varying size have been produced by introducing SO2 and H2O along with the radon to the chamber. In April 1988, intercomparison studies were performed between direct measurements of the activity-weighted size distributions as measured by graded screen arrays and an indirect measurement of the distribution obtained by measuring the number size distribution with a differential mobility analyzer and multiplying by the theoretical attachment rate. Good agreement was obtained in these measurements. A second set of intercomparison studies among a number of groups with graded screen array systems was made in April 1989 with the objective of resolving spectral structure below 10 nm. Again, generally good agreement among the various groups was obtained although some differences were noted. It is thus concluded that such systems can be constructed and can be useful in making routine measurements of activity-weighted size distributions with reasonable confidence in the results obtained. C1 ATOM ENERGY CORP S AFRICA LTD, PRETORIA 0001, SOUTH AFRICA. BATTELLE MEM INST, COLUMBUS LABS, COLUMBUS, OH 43201 USA. US DOE, ENVIRONM MEASURES LAB, NEW YORK, NY 10014 USA. OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. UR BUR MINES, DENVER RES CTR, DENVER, CO 80225 USA. INHALAT TOXICOL RES INST, ALBUQUERQUE, NM 87185 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. ATOM ENERGY AUTHOR TECHNOL, DIV ENVIRONM & MED SCI, B551 HARWELL LAB, HARWELL OX11 0RA, OXON, ENGLAND. AUSTRALIAN RADIAT LABS, YALLAMBIE, VIC 3085, AUSTRALIA. UNIV GOTTINGEN, ZENT ISOTOPENLAB, W-3400 GOTTINGEN, GERMANY. RP CLARKSON UNIV, DEPT CHEM, POTSDAM, NY 13676 USA. NR 38 TC 21 Z9 21 U1 0 U2 4 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA TWO COMMERCE SQ, 2001 MARKET ST, PHILADELPHIA, PA 19103 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD NOV PY 1992 VL 63 IS 5 BP 560 EP 570 DI 10.1097/00004032-199211000-00007 PG 11 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA JU480 UT WOS:A1992JU48000014 PM 1399642 ER PT J AU SMITH, LK PAYNE, SA KWAY, WL CHASE, LL CHAI, BHT AF SMITH, LK PAYNE, SA KWAY, WL CHASE, LL CHAI, BHT TI INVESTIGATION OF THE LASER PROPERTIES OF CR3+LISRGAF6 SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article ID PUMPED CR-LISRALF6 LASER; OPTICAL SPECTROSCOPY; PERFORMANCE; CR-3+; LICAALF6-CR-3+ AB Efficient laser performance of Cr-doped LiSrGaF6 (LiSGAF) has been demonstrated near 820 nm, using a Kr-laser pump source. Cr: LiSGAF is a new material that is closely related to the previously reported laser crystals, LiCaAlF6:Cr3+ (Cr:LiCAF) and LiSrAlF6:Cr3+(Cr:LiSAF). The emission cross section and lifetime were found to be 3.3 x 10(20) cm2 and 88 mus, respectively. Assessments of the absorption oscillator strengths reveal that LiSGAF possesses an odd-parity distortion at the Cr sites that is of intermediate magnitude, compared to LiCAF and LiSAF. C1 UNIV CENT FLORIDA,CREOL,ORLANDO,FL 32936. RP SMITH, LK (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 21 TC 88 Z9 90 U1 0 U2 6 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 NOV PY 1992 VL 28 IS 11 BP 2612 EP 2618 DI 10.1109/3.161320 PG 7 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA JU290 UT WOS:A1992JU29000012 ER PT J AU PAYNE, SA CHASE, LL SMITH, LK KWAY, WL KRUPKE, WF AF PAYNE, SA CHASE, LL SMITH, LK KWAY, WL KRUPKE, WF TI INFRARED CROSS-SECTION MEASUREMENTS FOR CRYSTALS DOPED WITH ER3+, TM3+, AND HO3+ SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article ID RARE-EARTH IONS; LAF3 SINGLE-CRYSTALS; ROOM-TEMPERATURE; STIMULATED-EMISSION; LASER-EMISSION; ENERGY-LEVELS; MU-M; YTTRIUM ORTHOALUMINATE; OPTICAL-SPECTRUM; PUMPED LASER AB The absorption and emission cross sections of the transition between the ground spin-orbit multiplet and the lowest excited multiplet have been measured for the Er3+, TM3+, and Ho3+ ions in a variety of crystalline hosts. The materials that were investigated include LiYF4, Bay2F8, Y3Al5O12, LaF3, KCaF3, YAlO3, and La2Be2O5. The absolute magnitude of the emission cross sections were determined from the absorption spectra, with the aid of the principle of reciprocity. The calculated radiative emission lifetimes derived from these measured cross sections agree well with the actual measured emission decay times for most materials. The potential use of these rare-earth-doped materials in pulsed laser applications required that the ground state exhibit adequate splitting to minimize the detrimental effects of the ground state thermal population, and also that the emission cross section be sufficiently large to permit efficient extraction of energy. The systems based on Ho3+ in the eightfold coordinated sites of LiYF4, Bay2F8, and Y3Al5O12 appear to be most promising for this type of energy storage amplifier application. RP PAYNE, SA (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 79 TC 554 Z9 564 U1 10 U2 61 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 NOV PY 1992 VL 28 IS 11 BP 2619 EP 2630 DI 10.1109/3.161321 PG 12 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA JU290 UT WOS:A1992JU29000013 ER PT J AU CHEN, KC WARNE, LK AF CHEN, KC WARNE, LK TI A UNIFORMLY VALID LOADED ANTENNA THEORY SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article AB A quasistatic layered approximation is used to simplify the layered solution for insulated antennas to the solution of a generalized impedance boundary value problem, whose solution is expressed in terms of an integral. This integral applies to three different cases of antennas: insulated antennas imbedded in a dense medium, insulated antennas imbedded in air (dielectric-coated antennas), and impedance-loaded antennas. These three antennas are referred to as loaded antennas. The branch cut contribution for large distances is given by the Sommerfeld space wave formula. The physical transition of loaded antennas to bare antennas is investigated through the asymptotic evaluation of this integral. Simple uniform formulas for loaded antenna current are derived and generalized to cover the same range of validity as the integral (there is a typically large parameter available for expansion of the integral). The direct calculation for the input admittance of loaded antennas is found to be consistent with the derived uniform formula for antenna current. For insulated antennas in a dense medium, the complete transmission line theory (defined in this paper) is found to be adequate to describe antenna current through the transition to bare antennas. RP CHEN, KC (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 19 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD NOV PY 1992 VL 40 IS 11 BP 1313 EP 1323 DI 10.1109/8.202709 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA KQ613 UT WOS:A1992KQ61300006 ER PT J AU LUNDSTROM, MS DODD, PE LOVEJOY, ML HARMON, ES MELLOCH, MR KEYES, BM HAMM, RA RITTER, D AF LUNDSTROM, MS DODD, PE LOVEJOY, ML HARMON, ES MELLOCH, MR KEYES, BM HAMM, RA RITTER, D TI ELECTRON-TRANSPORT IN THIN-BASE INP/INGAAS HBTS SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Meeting Abstract C1 PURDUE UNIV,SCH ELECT ENGN,W LAFAYETTE,IN 47907. NATL RENEWABLE ENERGY LAB,GOLDEN,CO. NR 2 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD NOV PY 1992 VL 39 IS 11 BP 2658 EP 2659 DI 10.1109/16.163521 PG 2 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA JU737 UT WOS:A1992JU73700074 ER PT J AU MARTENS, JS ZIPPERIAN, TE HIETALA, VM GINLEY, DS TIGGES, CP PHILLIPS, JM SIEGAL, MP AF MARTENS, JS ZIPPERIAN, TE HIETALA, VM GINLEY, DS TIGGES, CP PHILLIPS, JM SIEGAL, MP TI FLUX FLOW AMPLIFIERS AND LOGIC OPERATING MILLIMETER-WAVE FREQUENCIES SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Meeting Abstract C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. AT&T BELL LABS,MURRAY HILL,NJ 07974. NR 2 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 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD NOV PY 1992 VL 39 IS 11 BP 2669 EP 2670 DI 10.1109/16.163540 PG 2 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA JU737 UT WOS:A1992JU73700093 ER PT J AU SCHILS, GF AF SCHILS, GF TI A STATISTICAL ALGORITHM FOR EFFICIENT COMPUTATION OF CORRELATIONS SO IEEE TRANSACTIONS ON SIGNAL PROCESSING LA English DT Letter ID RECOGNITION AB A statistical method is employed to approximate the operation of correlation. By using Bernouli sampling to generate the template or correlation mask, a sparse template can be produced. The sampling procedure is shown to produce an unbiased estimate of the correlation signal. The variance of the output signal is also evaluated. Various approximation accuracies can be obtained by proper design of the correlation template. Because the templates produced by this technique are binary and sparse, the correlation operation can be implemented very efficiently. It is shown that the computational complexity of this algorithm for implementing correlations is N2 (for images), where N is the linear dimension of the images. The technique is illustrated on an example. RP SCHILS, GF (reprint author), SANDIA NATL LABS,DIV ADV TECHNOL,LIVERMORE,CA 94551, USA. NR 11 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 1053-587X J9 IEEE T SIGNAL PROCES JI IEEE Trans. Signal Process. PD NOV PY 1992 VL 40 IS 11 BP 2857 EP 2863 DI 10.1109/78.165680 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA JV470 UT WOS:A1992JV47000030 ER PT J AU ZAYAS, JR SCHWARZ, RI AF ZAYAS, JR SCHWARZ, RI TI EVIDENCE SUPPORTING THE ROLE OF A PROTEINACEOUS, LOOSELY BOUND EXTRACELLULAR MOLECULE IN THE CELL-DENSITY SIGNALING BETWEEN TENDON CELLS SO IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY-ANIMAL LA English DT Article DE CELL DENSITY; GROWTH REGULATION; EXTRACELLULAR MATRIX; SIGNALING; TENDON CELLS ID PROCOLLAGEN SYNTHESIS; DEPENDENT REGULATION; FIBROBLAST GROWTH; MESSENGER-RNA; CULTURE; COLLAGEN; MATRIX; STATE AB Normal cells in culture respond to cell density by altering their proliferation rates and their pattern of protein expression. Primary avian tendon (PAT) cells are a case in point where procollagen production increases approximately 10-fold at high cell density while proliferation almost ceases. In an earlier report focusing on the cell density regulation of procollagen expression, the signaling mechanism communicating the presence of other cells was shown to have the characteristics of a loosely bound component of the cell layer. Extending these studies to the cell density regulation of proliferation, the cell density signal (CDS) was again shown to be altered by medium agitation, stimulating cell division. Agitation, however, was only disruptive to cell signaling when there was a high ratio of medium to cells. When sufficient cells were present, agitation was less effective. Therefore, the CDS controlling procollagen production and the CDS controlling the inhibition of growth seemed to be linked because the signaling mechanism is disrupted in a parallel manner by agitation. However, the proliferative response of PAT cells is more complex in that there is also a positive influence at moderate cell density (>2 X 10(4) cells/cm2) on the rate of cell division. As a consequence, PAT cells would not proliferate into an area of low cell density, but within the same dish would rapidly fill an area of moderate density. PAT cells were capable of filling a pp between high cell density areas if the gap was less than 2 mm. Medium agitation also affected cells at low cell density in a different manner. It was inhibitory if all the cells were at low cell density but it was stimulatory if the cells at low cell density were in close proximity to cells at high cell density. In addition, medium conditioned by agitation over cells al a high cell density would stimulate cells at low cell density to divide and grow out into low cell density regions. Using the growth-promoting activity of the conditioned medium as an assay, this component of the CDS was shown to have unique characteristics: heat, pH, dithiothreitol (DTT) stable; tris ion and protease sensitive. By gel exclusion chromatography it was larger than 100 kDa. But after DTT treatment its mobility shifted to <30 kDa while retaining activity. RP ZAYAS, JR (reprint author), LAWRENCE BERKELEY LAB,DIV CELL & MOLEC BIOL,BLDG 934,BERKELEY,CA 94720, USA. NR 31 TC 6 Z9 6 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 NOV-DEC PY 1992 VL 28A IS 11-12 BP 745 EP 754 PG 10 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA KF500 UT WOS:A1992KF50000018 ER PT J AU STARR, JN KING, CJ AF STARR, JN KING, CJ TI WATER-ENHANCED SOLUBILITY OF CARBOXYLIC-ACIDS IN ORGANIC-SOLVENTS AND ITS APPLICATION TO EXTRACTION PROCESSES SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID THERMODYNAMICS; DISSOCIATION; MIXTURES AB Solubilities of carboxylic acids in certain organic solvents increase sharply as the concentration of water in the solvent increases. This phenomenon leads to a method of regeneration for solvent-extraction processes whereby coextracted water is selectively removed from the extract, such as by stripping, thereby precipitating the acid. The removal of a minor constituent to cause precipitation reduces energy consumption, in contrast with bulk removal of solvent. Solubilities of fumaric acid were measured in a number of organic solvents, with varying amounts of water in the organic phase. Cyclohexanone and methylcyclohexanone were chosen as solvents for which detailed solid-liquid and liquid-liquid equilibria were measured for adipic, fumaric, and succinic acids in the presence of varying concentrations of water, at both 25 and 45-degrees-C. Batch precipitation experiments were performed to demonstrate the processing concept and determine the relative volatility of water to solvent in the presence of carboxylic acid. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. NR 21 TC 24 Z9 26 U1 0 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD NOV PY 1992 VL 31 IS 11 BP 2572 EP 2579 DI 10.1021/ie00011a023 PG 8 WC Engineering, Chemical SC Engineering GA JX574 UT WOS:A1992JX57400023 ER PT J AU SADASIVAN, P CHAPPIDI, PR UNAL, C NELSON, RA AF SADASIVAN, P CHAPPIDI, PR UNAL, C NELSON, RA TI POSSIBLE MECHANISMS OF MACROLAYER FORMATION SO INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER LA English DT Article ID HIGH-HEAT-FLUX; POOL; THICKNESS; REGION AB This paper critically compares the mechanisms proposed for the formation of the liquid-rich macrolayer on heater surfaces during nucleate boiling. These mechanisms include Helmholtz instability analysis applied to vapor stems above active nucleation sites, liquid trapped by lateral coalescence of discrete bubbles that initally form during the mushroom bubble's waiting period, and the limitation of liquid resupply after mushroom departure as a result of vapor flow from active sites. RP SADASIVAN, P (reprint author), LOS ALAMOS NATL LAB,DIV NUCL TECHNOL & ENGN,ENGN & SAFETY ANAL GRP,LOS ALAMOS,NM 87545, USA. NR 17 TC 11 Z9 12 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0735-1933 J9 INT COMMUN HEAT MASS JI Int. Commun. Heat Mass Transf. PD NOV-DEC PY 1992 VL 19 IS 6 BP 801 EP 815 DI 10.1016/0735-1933(92)90016-B PG 15 WC Thermodynamics; Mechanics SC Thermodynamics; Mechanics GA JZ998 UT WOS:A1992JZ99800004 ER PT J AU STACEY, GJ BEEMAN, JW HALLER, EE GEIS, N POGLITSCH, A RUMITZ, M AF STACEY, GJ BEEMAN, JW HALLER, EE GEIS, N POGLITSCH, A RUMITZ, M TI STRESSED AND UNSTRESSED GE-GA DETECTOR ARRAYS FOR AIRBORNE ASTRONOMY SO INTERNATIONAL JOURNAL OF INFRARED AND MILLIMETER WAVES LA English DT Article DE INFRARED ASTRONOMY; INFRARED TECHNIQUES; PHOTOCONDUCTIVE DETECTOR ARRAY; CRYOGENIC ELECTRONICS ID LINE; PHOTOCONDUCTORS AB We have constructed and used two dimensional arrays of both unstressed and stressed Ge:Ga photoconductive detectors for far-infrared astronomy from the Kuiper Airborne Observatory (KAO). The 25 element (5 x 5) arrays are designed for a new cryogenically cooled spectrometer, the MPE/UCB Far-Infrared Imaging Fabry-Perot Interferometer (FIFI). All of the pixels for the stressed array performed well on the first flights with FIFI; 25% of the detectors in the array are more sensitive than our best single element detector, with background limited noise equivalent powers (NEPs) less than or similar to 3.0 x 10(-15) W Hz-1/2 at 158 mum and 40 km s-1 spectral resolution. The average array element performs within +/- 15% of this value. With a bias field of 0.1 V/cm, the average detector response is 20 +/- 6 Amp/Watt at 158 mum. The cutoff wavelength and response also compare well with our single element detectors. The unstressed array delivers significantly better performance than our single element detector due to the lower thermal background in the new spectrometer. The average background limited NEP at 88 mum and 35 km s-1 spectral resolution is approximately 7 x 10(-15) W Hz-1/2. The least sensitive pixel is only 40% less sensitive. The unstressed array response at 88 mum with a bias field of 1 V/cm is 5 +/- 1 Amp/Watt. Twenty four of the 25 elements worked on the first flights - on subsequent flights all channels have worked. Some of the exciting new science possible with far-infrared detector arrays is also discussed. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. MAX PLANCK INST PHYS & ASTROPHYS,W-8046 GARCHING,GERMANY. RP STACEY, GJ (reprint author), CORNELL UNIV,DEPT ASTRON,ITHACA,NY 14853, USA. NR 18 TC 50 Z9 50 U1 1 U2 2 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-9271 J9 INT J INFRARED MILLI JI Int. J. Infrared Millimeter Waves PD NOV PY 1992 VL 13 IS 11 BP 1689 EP 1707 DI 10.1007/BF01010739 PG 19 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA JR527 UT WOS:A1992JR52700001 ER PT J AU KETO, E BALL, R ARENS, J JERNIGAN, G MEIXNER, M AF KETO, E BALL, R ARENS, J JERNIGAN, G MEIXNER, M TI CHARACTERIZATION OF SOLID-STATE ARRAY CAMERAS FOR THE MID-IR SO INTERNATIONAL JOURNAL OF INFRARED AND MILLIMETER WAVES LA English DT Article DE INFRARED ASTRONOMY; INFRARED INSTRUMENTS; INFRARED IMAGING; DETECTOR ARRAYS AB We present a characterization of some processes affecting the performance of solid state array cameras designed for ground based astronomical imaging in the 8-13mum atmospheric window. Our discussion includes a novel model for electron-hole generation-recombination noise based on the probable pathlength of an electron in a photoconductor. We use the Berkeley mid-IR Array Camera as an example. For this camera, the results show that the total optical system composed of the camera, a 3m telescope, and the atmosphere has an efficiency of about 3%, a 1sigma noise equivalent flux density of 25 mJy min-1/2 arcsec-2 measured over a DELTAlambda/lambda = 10% band width, and a noise equivalent expressed as the ambient temperature thermal black body noise of 23%. RP KETO, E (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808 L-59,LIVERMORE,CA 94550, USA. NR 10 TC 15 Z9 15 U1 0 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-9271 J9 INT J INFRARED MILLI JI Int. J. Infrared Millimeter Waves PD NOV PY 1992 VL 13 IS 11 BP 1709 EP 1725 DI 10.1007/BF01010740 PG 17 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA JR527 UT WOS:A1992JR52700002 ER PT J AU KRAYNIK, AM REINELT, DA AF KRAYNIK, AM REINELT, DA TI EXTENSIONAL MOTIONS OF SPATIALLY PERIODIC LATTICES SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Article DE COMPATIBILITY; EXTENSIONAL FLOW; LATTICE; MICRORHEOLOGY; PLANAR EXTENSION; PERIODICITY; SPATIALLY PERIODIC; UNIT CELL ID LINEAR SHEAR FLOWS; CONVEX PARTICLES; SUSPENSIONS; EMULSIONS; FOAMS AB The behavior of microrheological models for multiphase fluids that have spatially periodic structure depends on certain kinematic properties of the unit cell. Anomalous results associated with identical objects approaching too closely during the flow can be reduced if not eliminated by satisfying lattice compatibility conditions. This is straightforward for simple shearing flow but subtle for extensional flows. Using the connection between lattice compatibility and lattice reproducibility (periodic lattice behavior with the flow) we establish sufficient conditions for compatibility of arbitrary lattices in planar extensional flow. Detailed results for square and hexagonal unit cells include: initial orientations for periodic behavior; strain periods; and minimum lattice spacings D. We identify the orientation of a square unit cell that leads to periodic behavior (with the minimum period) and the largest D of any lattice in planar extensional flow. We show that no lattice exhibits periodic behavior in uniaxial extensional flow (or biaxial extensional flow) even though Adler & Brenner have established the existence of compatibility. C1 SO METHODIST UNIV,DEPT MATH,DALLAS,TX 75275. RP KRAYNIK, AM (reprint author), SANDIA NATL LABS,DEPT 1512,ALBUQUERQUE,NM 87185, USA. NR 11 TC 74 Z9 74 U1 1 U2 15 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD NOV PY 1992 VL 18 IS 6 BP 1045 EP 1059 DI 10.1016/0301-9322(92)90074-Q PG 15 WC Mechanics SC Mechanics GA KE724 UT WOS:A1992KE72400016 ER PT J AU ILIC, V TULLOCK, D PHANTHIEN, N GRAHAM, AL AF ILIC, V TULLOCK, D PHANTHIEN, N GRAHAM, AL TI TRANSLATION AND ROTATION OF SPHERES SETTLING IN SQUARE AND CIRCULAR CONDUITS - EXPERIMENTS AND NUMERICAL PREDICTIONS SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Article DE FALLING SPHERE; SPHERE; CYLINDERS; SQUARE CONDUITS; ROTATION; WALL CORRECTION FACTOR; DRAG; STOKES LAW ID VISCOMETRY; PARTICLE; FLOWS; TUBES; WALL AB The terminal settling velocities and rotation rates of spherical particles settling in circular and square conduits were investigated experimentally and numerically with the aim to benchmark the numerical predictions using the boundary element method. Spheres were allowed to settle in viscous Newtonian fluid under conditions such that only hydrodynamic forces exerted an appreciable effect. The terminal settling velocities and the rotation rates were measured as a function of the size and density of the falling sphere, the drop position of the sphere in the conduit and the dimensions and geometry of the containing vessel or conduit. The experimental measurements were subjected to an exacting error analysis and compared with fully three-dimensional boundary element calculations. We found that the results of the experiments and numerical simulations showed remarkable agreement within the bounds of experimental error. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP ILIC, V (reprint author), UNIV SYDNEY,DEPT MECH ENGN,SYDNEY,NSW 2006,AUSTRALIA. RI Phan-Thien, Nhan/I-4705-2012 NR 46 TC 15 Z9 15 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD NOV PY 1992 VL 18 IS 6 BP 1061 EP 1075 DI 10.1016/0301-9322(92)90075-R PG 15 WC Mechanics SC Mechanics GA KE724 UT WOS:A1992KE72400017 ER PT J AU NIEH, TG WADSWORTH, J AF NIEH, TG WADSWORTH, J TI SUPERPLASTICITY AND SUPERPLASTIC FORMING OF ALUMINUM METAL-MATRIX COMPOSITES SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article ID ALLOY; BEHAVIOR; PHASE RP NIEH, TG (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,LIVERMORE,CA 94550, USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 20 TC 31 Z9 31 U1 1 U2 4 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 NOV PY 1992 VL 44 IS 11 BP 46 EP 51 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA JY343 UT WOS:A1992JY34300009 ER PT J AU TOMKINS, BA MERRIWEATHER, R JENKINS, RA BAYNE, CK AF TOMKINS, BA MERRIWEATHER, R JENKINS, RA BAYNE, CK TI DETERMINATION OF 8 ORGANOCHLORINE PESTICIDES AT LOW NANOGRAM LITER CONCENTRATIONS IN GROUNDWATER USING FILTER DISK EXTRACTION AND GAS-CHROMATOGRAPHY SO JOURNAL OF AOAC INTERNATIONAL LA English DT Article ID PHASE AB Eight organochlorine pesticides may be quantitated routinely at levels below 10 parts per trillion (ng/L) in natural groundwaters. Analytes are extracted rapidly from 1 L groundwater samples by using conditioned Teflon filter disks impregnated with silica containing bonded octadecyl phase. Filter is dried briefly under vacuum, and pesticides are eluted with 10 m L ethyl acetate. The extract is dried with about 1 g anhydrous sodium sulfate and then concentrated to exactly 1 mL. Pesticides are separated in a gas chromatograph equipped with a capillary column, detected by a high-sensitivity electron capture detector, and quantitated by the method of external standards. Certified reporting limit (CRL) values for the 8 pesticides ranged between 2 and 7 ng/L. Preliminary data demonstrated that the organochlorine pesticides could be collected on the filter disks and stored up to 4 weeks in the dark at either refrigerated or ambient temperature without obvious degradation of the sample. Calculated CRL values are comparable (within a factor of 2) to method detection limit values defined by the U.S. Environmental Protection Agency. C1 OAK RIDGE NATL LAB,DIV COMP & TELECOMMUN,OAK RIDGE,TN 37831. RP TOMKINS, BA (reprint author), OAK RIDGE NATL LAB,DIV ANALYT CHEM,ORGAN CHEM SECT,POB 2008,OAK RIDGE,TN 37831, USA. NR 13 TC 44 Z9 45 U1 0 U2 3 PU AOAC INTERNATIONAL PI GAITHERSBURG PA 481 NORTH FREDRICK AVE, STE 500, GAITHERSBURG, MD 20877-2504 SN 1060-3271 J9 J AOAC INT JI J. AOAC Int. PD NOV-DEC PY 1992 VL 75 IS 6 BP 1091 EP 1099 PG 9 WC Chemistry, Analytical; Food Science & Technology SC Chemistry; Food Science & Technology GA JZ460 UT WOS:A1992JZ46000022 ER PT J AU JAIN, R ADLER, TC MCLARNON, FR CAIRNS, EJ AF JAIN, R ADLER, TC MCLARNON, FR CAIRNS, EJ TI DEVELOPMENT OF LONG-LIVED HIGH-PERFORMANCE ZINC CALCIUM NICKEL-OXIDE CELLS SO JOURNAL OF APPLIED ELECTROCHEMISTRY LA English DT Article ID KOH CONCENTRATION; ZN/NIOOH CELLS; CYCLE-LIFE; ELECTRODES; HYDROXIDE; KINETICS AB The addition of Ca(OH)2 to the zinc electrode of Zn/KOH/NiOOH cells was investigated in order to determine its effect on the rate of zinc active material redistribution (shape change) and cell cycle-life performance. Cells of equal mass and capacity, and therefore the same specific energy, containing 0, 10, 25, and 40 mol % Ca(OH)2 in their zinc electrodes were constructed and tested. The Ca(OH)2 and Zn(OH)42--supersaturated KOH solution formed a calcium-zincate complex during the discharge half-cycle. The solubility of this complex is less than that of ZnO, and the lower zinc species solubility leads to a slower rate of Zn redistribution, thereby extending the cell cycle life. The best cells tested were those with 25%-Ca(OH)2 electrodes, which lost capacity at a rate of 0.13%/cycle, compared to 0.47%/cycle in calcium-free control cells constructed in the same manner. Also, zinc active material utilization in the calcium-containing electrodes showed a dramatic improvement, compared to the calcium-free zinc electrodes. C1 LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 33 TC 41 Z9 46 U1 1 U2 11 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0021-891X J9 J APPL ELECTROCHEM JI J. Appl. Electrochem. PD NOV PY 1992 VL 22 IS 11 BP 1039 EP 1048 DI 10.1007/BF01029582 PG 10 WC Electrochemistry SC Electrochemistry GA JX115 UT WOS:A1992JX11500007 ER PT J AU CHEN, GL MEI, VC CHEN, FC AF CHEN, GL MEI, VC CHEN, FC TI ANALYSIS OF TERBIUM THERMODYNAMIC CHARACTERISTICS FOR MAGNETIC HEAT-PUMP APPLICATIONS SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Based on molecular field theory, including the effect of the field-dependent nature of Neel temperature, the entropy, and the magnetocaloric effect in terbium (Tb) have been calculated with the external field between 0 and 7 T (Tesla). The calculated results are compared with the existing experimental measurements. The maximum magnetocaloric temperature change (DELTAT) is approximately 14 K near the zero-field Neel temperature (230 K) for an external field at 7 T field. This relatively large magnetocaloric effect indicates that Th could be an attractive candidate for magnetic heat pump application. The results are then used to study the performance of heat pumps for the Carnot cycle, the constant field cycle, and the ideal regenerative cycle. The performances of these three cycles are discussed and compared. RP CHEN, GL (reprint author), OAK RIDGE NATL LAB,POB 2008,OAK RIDGE,TN 37831, USA. NR 13 TC 7 Z9 7 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 NOV 1 PY 1992 VL 72 IS 9 BP 3908 EP 3911 DI 10.1063/1.352267 PG 4 WC Physics, Applied SC Physics GA JW937 UT WOS:A1992JW93700009 ER PT J AU BUTLER, MA BUSS, RJ AF BUTLER, MA BUSS, RJ TI MOLECULAR-DIFFUSION IN PLASMA-POLYMERIZED TETRAFLUOROETHYLENE SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SENSOR AB Diffusion of an array of molecules in micrometer-thick films of plasma-polymerized tetrafluoroethylene has been measured using an optical interferometric technique. The diffusivity is approximately independent of molecular size up to a molar volume of about 100 cm3 and drops rapidly for larger molecules. For much larger molecules no penetration of the films is observed. These results suggest that plasma-polymerized tetrafluoroethylene films are heavily cross linked and that this limits the size of the molecules that can penetrate the polymer. The temperature dependence and the molecular size dependence of the diffusivities are discussed in the context of free-volume theory. RP BUTLER, MA (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. 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 NOV 1 PY 1992 VL 72 IS 9 BP 4041 EP 4046 DI 10.1063/1.352259 PG 6 WC Physics, Applied SC Physics GA JW937 UT WOS:A1992JW93700027 ER PT J AU MOCHIJI, K LEE, K MA, CI KIM, DY MAHALINGAM, M HANSON, DM JOHNSON, ED AF MOCHIJI, K LEE, K MA, CI KIM, DY MAHALINGAM, M HANSON, DM JOHNSON, ED TI HIGH-RESOLUTION TIME-OF-FLIGHT ANALYSIS OF PHOTON STIMULATED ION DESORPTION FROM CHEMICALLY TREATED SILICON SURFACES SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID AUGER-ELECTRON SPECTROSCOPY; CLEANING HF/UVOC METHOD; X-RAY PHOTOELECTRON; HF TREATMENT; INFRARED-SPECTROSCOPY; HYDROGEN TERMINATION; PASSIVATED SILICON; SI(100) SURFACES; MORPHOLOGY; SI(111) AB The native oxide, thermally oxidized and hydrofluoric acid rinsed surfaces of Si(100) have been characterized by photon stimulated ion desorption (PSD), and both photoelectron and Auger electron spectroscopies. The only species detected by PSD were H+ ions with different kinetic energies. Low kinetic energy H+ ions were detected only from the HF rinsed surfaces presumable arising from scission of Si-H bonds while higher kinetic energy ions attributed to adsorbed hydrocarbon dissociation were observed for all of the surfaces. C1 BROOKHAVEN NATL LAB, NATL SYNCHROTRON LIGHT SOURCE, UPTON, NY 11973 USA. HITACHI LTD, CENT RES LAB, KOKUBUNJI, TOKYO 185, JAPAN. RP MOCHIJI, K (reprint author), SUNY STONY BROOK, DEPT CHEM, STONY BROOK, NY 11794 USA. NR 29 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 1992 VL 72 IS 9 BP 4156 EP 4160 DI 10.1063/1.352224 PG 5 WC Physics, Applied SC Physics GA JW937 UT WOS:A1992JW93700043 ER PT J AU PAYNE, MG CHEN, CH GARRETT, WR TEMPLETON, D AF PAYNE, MG CHEN, CH GARRETT, WR TEMPLETON, D TI HIGH-INTENSITY LASER-BEAM ATTENUATION BASED ON 2-STEP ABSORPTION MECHANISM SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Due to rapid progress in the development of high-power tunable visible lasers, it is expected that eye protection from tunable lasers in the open field will be needed in the near future. A nonlinear method is proposed that will transmit low-intensity light, but absorb light at high intensities. This high-intensity attenuator is based on the use of a liquid or solid made up of molecules having the property of undergoing two-photon photodissociation through most of the visible part of the spectrum. This material must also have the additional property that one of the products of the photodissociation is a one-photon absorber throughout the same wavelength region. It is suggested that the laser beam intensity can be attenuated by a large factor through these two-step absorption mechanisms, and that if the one-photon absorbing product is quenched by collisions with some component of the liquid in a time that is small compared with the laser pulse length, very large attenuation can be achieved from the built-up concentration of one-photon absorbers. Thus, the early part of a laser pulse is attenuated by two-photon absorption only, but the later parts of the pulse can be attenuated by factors as large as 10(5). Using a double-pass geometry, the leading edge of the pulse can be absorbed by linearly absorbing species formed on the first pass. The double-pass method, with an optical delay line, can even work well with picosecond pulses. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. AMSTA RSC,USA TANK AUTOMOT COMMAND,WARREN,MI 48397. NR 16 TC 9 Z9 10 U1 1 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 NOV 1 PY 1992 VL 72 IS 9 BP 4281 EP 4287 DI 10.1063/1.352189 PG 7 WC Physics, Applied SC Physics GA JW937 UT WOS:A1992JW93700064 ER PT J AU BRUNCO, DP THOMPSON, MO OTIS, CE GOODWIN, PM AF BRUNCO, DP THOMPSON, MO OTIS, CE GOODWIN, PM TI TEMPERATURE-MEASUREMENTS OF POLYIMIDE DURING KRF EXCIMER LASER ABLATION SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID POLYMER ABLATION; PHOTOABLATION; ABSORPTION; RADIATION; KAPTON; FILMS; NM AB The temperature at the interface between a thin polyimide film and a quartz substrate was monitored as a function of time during KrF (248 nm) laser-induced heating and ablation using thin film NiSi thermistors. These experimental temperature measurements were coupled with heat flow simulations to obtain time-resolved temperature profiles in the polyimide. Thermal properties of the polyimide were estimated by requiring that the simulations reproduce experimental temperature profiles. The peak surface temperature of the polyimide at the onset of ablation was subsequently estimated from these constrained simulations and a value of 1660 +/- 100 K was obtained for the observed ablation threshold fluence of 36 mJ/cm2. C1 IBM CORP,THOMAS J WATSON RES CTR,YORKTOWN HTS,NY 10598. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP BRUNCO, DP (reprint author), CORNELL UNIV,DEPT MAT SCI & ENGN,BARD HALL,ITHACA,NY 14853, USA. OI Thompson, Michael/0000-0002-4933-009X NR 32 TC 41 Z9 41 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 NOV 1 PY 1992 VL 72 IS 9 BP 4344 EP 4350 DI 10.1063/1.352198 PG 7 WC Physics, Applied SC Physics GA JW937 UT WOS:A1992JW93700073 ER PT J AU LEMKE, RW AF LEMKE, RW TI DISPERSION ANALYSIS OF SYMMETRICAL TRANSVERSE MAGNETIC-MODES IN A SPLIT CAVITY OSCILLATOR SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB The split cavity oscillator (SCO) is a resonant cavity device which can be used to modulate the current of a relativistic electron beam. The modulated electron beam can be used to produce high-power microwaves. The SCO consists of a cylindrical cavity resonator which has been divided (split) into two identical regions (cavities) by a thin conducting foil (or screen) whose radius is less than the inner radius of the cylinder. The resulting gap between the foil perimeter and inner cylinder wall forms an annular slot which couples the cavities electromagnetically. The SCO supports standard transverse magnetic (TM) modes, in addition to split cavity TM modes. The latter will interact unstably with an electron beam, thereby producing a high degree of current modulation in a short distance. For the purpose of characterizing split cavity TM modes, and developing a design tool for SCOs, a cold dispersion relation (no electron beam) is derived by solving Maxwell's equations for the fields in an equivalent periodic structure. The dispersion relation and field solutions are employed to numerically calculate eigenfrequencies and eigenfunctions for the SCO. The latter are used to develop predictive formula for the SCO oscillation frequency, and to gain some understanding of the interaction that takes place when an electron beam is present. RP LEMKE, RW (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 4 TC 20 Z9 27 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 NOV 1 PY 1992 VL 72 IS 9 BP 4422 EP 4428 DI 10.1063/1.352209 PG 7 WC Physics, Applied SC Physics GA JW937 UT WOS:A1992JW93700084 ER PT J AU HUBBARD, KM JERVIS, TR MIRKARIMI, PB BARNETT, SA AF HUBBARD, KM JERVIS, TR MIRKARIMI, PB BARNETT, SA TI MECHANICAL-PROPERTIES OF EPITAXIAL TIN/(V0.6NB0.4)N SUPERLATTICES MEASURED BY NANOINDENTATION SO JOURNAL OF APPLIED PHYSICS LA English DT Note ID THIN-FILMS; HARDNESS AB We have used nanoindentation to measure the mechanical properties of epitaxial TiN/(V0.6Nb0.4)N superlattices, grown on MgO(100), as a function of the wavelength lambda. The V/Nb ratio within the VNbN layers was chosen to provide a lattice match with TiN, minimizing effects resulting from coherency strains. For lambda greater-than-or-equal-to 4 nm, the hardness was found to be significantly enhanced relative to a homogeneous reference film of the same average composition. For lambda < 4 nm, the hardness decreased to a value close to that of the reference film. The elastic modulus was found to be constant for lambda greater-than-or-equal-to 4 nm, at a value close to that predicted by the law of mixtures. For samples with lambda = 2.3 and 2.8 nm, there was a 15 % decrease in modulus. The observed variations appear not to be an effect of interfacial strain. Possible mechanisms are discussed. C1 NORTHWESTERN UNIV,EVANSTON,IL 60202. RP HUBBARD, KM (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Barnett, Scott/B-7502-2009 NR 17 TC 18 Z9 18 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 1992 VL 72 IS 9 BP 4466 EP 4468 DI 10.1063/1.352177 PG 3 WC Physics, Applied SC Physics GA JW937 UT WOS:A1992JW93700094 ER PT J AU BISCHOF, JC BASTACKY, J RUBINSKY, B AF BISCHOF, JC BASTACKY, J RUBINSKY, B TI AN ANALYTICAL STUDY OF CRYOSURGERY IN THE LUNG SO JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID CRYOTHERAPY AB The process of freezing in healthy lung tissue and in tumors in the lung during cryosurgery was modeled using one-dimensional close form techniques and finite difference techniques to determine the temperature profiles and the propagation of the freezing interface in the tissue. A thermal phenomenon was observed during freezing of lung tumors embedded in healthy tissue, (a) the freezing interface suddenly accelerates at the transition between the tumor and the healthy lung, (b) the frozen tumor temperature drops to low values once the freezing interface moves into the healthy lung, and (c) the outer boundary temperature has a point of sharp inflection corresponding to the time at which the tumor is completely frozen. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP BISCHOF, JC (reprint author), UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720, USA. RI Rubinsky, Boris/B-4439-2010 OI Rubinsky, Boris/0000-0002-2794-1543 FU NHLBI NIH HHS [HL 40521, HL 45021]; NIGMS NIH HHS [5 T32GM07379] NR 20 TC 21 Z9 21 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0148-0731 J9 J BIOMECH ENG-T ASME JI J. Biomech. Eng.-Trans. ASME PD NOV PY 1992 VL 114 IS 4 BP 467 EP 472 DI 10.1115/1.2894096 PG 6 WC Biophysics; Engineering, Biomedical SC Biophysics; Engineering GA KB055 UT WOS:A1992KB05500006 PM 1487898 ER PT J AU TOMIC, MT SOMOZA, JR WEMMER, DE PARK, YW CHO, JM KIM, SH AF TOMIC, MT SOMOZA, JR WEMMER, DE PARK, YW CHO, JM KIM, SH TI H-1 RESONANCE ASSIGNMENTS, SECONDARY STRUCTURE AND GENERAL TOPOLOGY OF SINGLE-CHAIN MONELLIN IN SOLUTION AS DETERMINED BY H-1 2D-NMR SO JOURNAL OF BIOMOLECULAR NMR LA English DT Article DE MONELLIN; SWEET PROTEIN; H-1 ASSIGNMENTS; ENGINEERED LOOP ID NUCLEAR MAGNETIC-RESONANCE; COHERENCE TRANSFER; TRANSFER SPECTROSCOPY; H-1-NMR SPECTRA; SWEET PROTEIN; NMR; IDENTIFICATION; RESOLUTION AB We determined the resonance assignments, secondary structure and general topology of the 11-kDa sweet protein single-chain monellin (SCM), using two-dimensional proton nuclear magnetic resonance spectroscopy (2D-NMR). SCM is a genetically engineered protein whose design is based on the crystal structure of natural, two-chain monellin (Kim et al., 1989). Analysis of the NMR spectra shows that the secondary structure of SCM consists of a five-strand anti-parallel beta-sheet and a 15-residue alpha-helix. Tertiary NOE constraints place the alpha-helix on the hydrophobic side of the beta-sheet, and indicate that the sheet is partially wrapped around the helix. The general structural features determined for SCM are similar to those of native monellin (Ogata et al., 1987). Some differences between the SCM structure in solution and the crystal structure of monellin are discussed. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CALIF BERKELEY,GRAD GRP BIOPHYS,BERKELEY,CA 94720. LUCKY BIOTECH CORP,EMERYVILLE,CA 94608. RP WEMMER, DE (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720, USA. FU NIDCD NIH HHS [DC 00145] NR 23 TC 14 Z9 14 U1 0 U2 0 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 NOV PY 1992 VL 2 IS 6 BP 557 EP 572 DI 10.1007/BF02192845 PG 16 WC Biochemistry & Molecular Biology; Spectroscopy SC Biochemistry & Molecular Biology; Spectroscopy GA KD161 UT WOS:A1992KD16100003 PM 1490107 ER PT J AU ZHANG, R SCHWARZ, JA DATYE, A BALTRUS, JP AF ZHANG, R SCHWARZ, JA DATYE, A BALTRUS, JP TI THE EFFECT OF 2ND-PHASE OXIDES ON THE CATALYTIC PROPERTIES OF DISPERSED METALS - PALLADIUM SUPPORTED ON 12-PERCENT-WO3/AL2O3 SO JOURNAL OF CATALYSIS LA English DT Article ID RUTHENIUM CATALYSTS; PARTICLE-SIZE; ALUMINA; HYDROGENATION; TEMPERATURE; NICKEL C1 SYRACUSE UNIV,DEPT CHEM ENGN & MAT SCI,SYRACUSE,NY 13244. UNIV NEW MEXICO,DEPT CHEM & NUCL ENGN,ALBUQUERQUE,NM 87131. US DOE,PITTSBURGH ENERGY TECHNOL CTR,PITTSBURGH,PA 15236. NR 24 TC 19 Z9 20 U1 1 U2 6 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9517 J9 J CATAL JI J. Catal. PD NOV PY 1992 VL 138 IS 1 BP 55 EP 69 DI 10.1016/0021-9517(92)90006-4 PG 15 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA JU777 UT WOS:A1992JU77700005 ER PT J AU ARNOLD, CC ZHAO, YX KITSOPOULOS, TN NEUMARK, DM AF ARNOLD, CC ZHAO, YX KITSOPOULOS, TN NEUMARK, DM TI STUDY OF C-6(-) AND C-6 WITH THRESHOLD PHOTODETACHMENT SPECTROSCOPY AND AUTODETACHMENT SPECTROSCOPY SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LASER ABSORPTION-SPECTROSCOPY; INDUCED ELECTRON DETACHMENT; FLIGHT MASS-SPECTROMETER; SMALL CARBON CLUSTERS; INFRARED FREQUENCIES; NEGATIVE-IONS; BOUND STATES; RESOLUTION; BAND; MOLECULES AB The C6- anion and C6 neutral have been studied using both threshold photodetachment (zero electron kinetic energy) spectroscopy and autodetachment spectroscopy of C6-. The threshold photodetachment spectrum yields the electron affinity of linear C6 to high accuracy, along with the three symmetric stretch frequencies for linear C6 and the spin-orbit splitting in the ground 2PI(u) state of the anion. Two of the symmetric stretch frequencies are significantly lower than previous ab initio predictions. A simple model force field is used to calculate stretching force constants and estimate bond length changes between the anion and neutral. In addition, using autodetachment spectroscopy, we have located an excited electronic state of C6- that lies 43 cm-1 below the detachment threshold. This state is very similar in geometry to neutral C6. Excited vibrational levels of this state autodetach with rates that depend strongly on the available autodetachment channels. The excited state is tentatively assigned to a valence state, rather than an electrostatically bound state. C1 LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720. RP ARNOLD, CC (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720, USA. RI Kitsopoulos, Theofanis/A-8355-2014; Neumark, Daniel/B-9551-2009 OI Neumark, Daniel/0000-0002-3762-9473 NR 82 TC 75 Z9 75 U1 2 U2 7 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 NOV 1 PY 1992 VL 97 IS 9 BP 6121 EP 6135 DI 10.1063/1.463722 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500018 ER PT J AU CHANG, J BROWN, NJ DMELLO, M WYATT, RE RABITZ, H AF CHANG, J BROWN, NJ DMELLO, M WYATT, RE RABITZ, H TI QUANTUM FUNCTIONAL SENSITIVITY ANALYSIS WITHIN THE LOG-DERIVATIVE KOHN VARIATIONAL METHOD FOR REACTIVE SCATTERING SO JOURNAL OF CHEMICAL PHYSICS LA English DT Review ID POTENTIAL-ENERGY SURFACE; INTEGRAL CROSS-SECTIONS; S-MATRIX VERSION; MECHANICAL REACTION PROBABILITIES; BIMOLECULAR CHEMICAL-REACTIONS; HYDROGEN-EXCHANGE REACTION; STATE REACTION DYNAMICS; MANY-BODY EXPANSION; COLLISION ENERGIES; H+H2 REACTION AB A new approach to calculating quantum functional sensitivity maps of transition probabilities is described in this paper. This approach is based on the log-derivative version of the Kohn variational principle and is applied here to the collinear H + H-2 hydrogen exchange reaction. The sensitivity maps provide detailed quantitative information about how variations in the potential energy surface affect the state-to-state transition probabilities. The key issues investigated are (i) the evolution of sensitivity structure in the 0.30-1.50 eV range of total energy; (ii) the comparison of sensitivity structure on the Porter-Karplus, the Liu-Siegbahn-Truhlar-Horowitz, and the double-many-body-expansion potential energy surfaces; and (iii) the range of linearity for first order sensitivity predictions. C1 THINKING MACHINES CORP,CAMBRIDGE,MA 02142. UNIV TEXAS,DEPT CHEM,AUSTIN,TX 78712. UNIV TEXAS,INST THEORET CHEM,AUSTIN,TX 78712. PRINCETON UNIV,DEPT CHEM,PRINCETON,NJ 08544. RP CHANG, J (reprint author), LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,BERKELEY,CA 94720, USA. NR 106 TC 10 Z9 10 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 NOV 1 PY 1992 VL 97 IS 9 BP 6226 EP 6239 DI 10.1063/1.463706 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500029 ER PT J AU CHANG, J BROWN, NJ DMELLO, M WYATT, RE RABITZ, H AF CHANG, J BROWN, NJ DMELLO, M WYATT, RE RABITZ, H TI PREDICTING OBSERVABLES ON DIFFERENT POTENTIAL-ENERGY SURFACES USING FEATURE SENSITIVITY ANALYSIS - APPLICATION TO THE COLLINEAR H+H2 EXCHANGE-REACTION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID INTEGRAL CROSS-SECTIONS; KOHN VARIATIONAL PRINCIPLE; MANY-BODY EXPANSION; QUANTUM-MECHANICAL CALCULATION; LOG DERIVATIVE VERSION; S-MATRIX VERSION; PHOTODETACHMENT SPECTRUM; SCATTERING CALCULATIONS; HYPERSPHERICAL METHOD; REACTION F+H2->HF+H AB Two sensitivity-analysis techniques are used to show how one can predict observables on new or perturbed potential energy surfaces (PES) without doing any additional dynamics calculations on the new PESs. Both techniques require the computation of the observable (O) and its sensitivity to variations in the potential (deltaO/deltaV) on just one surface. The first approach uses a simple first order expansion of the observable with respect to deltaV. The second approach uses a nonlinear least-squares fit of particular features in the observable, and then uses the same functional form to predict the observable on a different PES but with a modified set of fitting parameters. The new fitting parameters are related to the old via a functional Taylor expansion. Both approaches work well when variations in the potential are small. When the potential difference is large, the second approach gives reasonable results even in cases where the first approach is giving spurious predictions. These ideas are tested for the collinear H + H-2 reaction within the framework of quantum reactive scattering. The log-derivative version of the Kohn variational principle is used for the scattering calculations. C1 THINKING MACHINES CORP,CAMBRIDGE,MA 02142. UNIV TEXAS,DEPT CHEM,AUSTIN,TX 78712. UNIV TEXAS,INST THEORET CHEM,AUSTIN,TX 78712. PRINCETON UNIV,DEPT CHEM,PRINCETON,NJ 08544. RP CHANG, J (reprint author), LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,BERKELEY,CA 94720, USA. NR 50 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 1 PY 1992 VL 97 IS 9 BP 6240 EP 6248 DI 10.1063/1.463685 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500030 ER PT J AU HESSLER, JP OGREN, PJ AF HESSLER, JP OGREN, PJ TI CORRELATION-ANALYSIS OF COMPLEX KINETIC SYSTEMS - A NEW SCHEME FOR UTILIZING SENSITIVITY COEFFICIENTS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CHEMICAL-KINETICS; PARAMETER-ESTIMATION AB A procedure for designing and evaluating kinetic experiments on complex chemical systems is presented. This procedure uses he temporal integral of products of sensitivity coefficients (which may be calculated by standard methods) (1) to calculate the relative importance of reactions affecting the kinetic behavior of a specific observable and (2) to evaluate the correlation between any of the above reactions. The advantages of this procedure are that it is directly related to the analysis of experimental data, conceptually simple, easy to implement, and it provides a quantitative means for assessing the relative accuracy of different experiments. In addition, it provides a new, efficient, and systematic method for calculating the correlation between reactions and determines how the uncertainties in the rate coefficients of these reactions propagate in an analysis of experimental errors We illustrate the essential features of the approach by analyzing recent measurements of the rate coefficients for H-2 + M <-- --> 2H + M and H + O2 <-- --> OH + O [J. Chem. Phys. 96, 1077 (1992)]. C1 EARLHAM COLL,DEPT CHEM,RICHMOND,IN 47374. RP HESSLER, JP (reprint author), ARGONNE NATL LAB,DIV CHEM,GAS PHASE CHEM DYNAM GRP,ARGONNE,IL 60439, USA. NR 28 TC 8 Z9 8 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 1 PY 1992 VL 97 IS 9 BP 6249 EP 6258 DI 10.1063/1.463686 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500031 ER PT J AU HSU, CW LIAO, CL MA, ZX TJOSSEM, PJH NG, CY AF HSU, CW LIAO, CL MA, ZX TJOSSEM, PJH NG, CY TI A STUDY OF THE S(P-3(2,1,0) (1)D(2)) PRODUCTION IN THE 193 NM PHOTODISSOCIATION OF CH3S((X)OVER-TILDE) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LASER-INDUCED FLUORESCENCE; VACUUM ULTRAVIOLET PHOTODISSOCIATION; COOLED POLYATOMIC RADICALS; RADIATIVE LIFETIMES; ROTATIONAL ANALYSIS; CROSS-SECTIONS; CH3S; PHOTOIONIZATION; KINETICS; CS2 AB The dynamics of (S(P2,1,0;1D2))-P-3 production from the 193 nm photodissociation of CH3SCH3 has been studied using 2 + 1 resonance-enhanced multiphoton ionization techniques. The 193 nm photodissociation cross section for the formation of S from CH3S initially prepared in the photodissociation of CH3SCH3 is estimated to be 1 X 10(-18) cm2. The branching ratio for (S(P)/S(1D))-P-3 is found to be 0.15/0.85. The fine-structure distribution observed for product (S(P2,1,0))-P-3 is nearly statistical. Possible potential energy surfaces involved in the 193 nm photodissociation of CH3S(X) have been examined theoretically along the CH3-S dissociation coordinate in C3v symmetry. These calculations suggest that predissociation of CH3S(C2A2) via the repulsive CH3S(E2E) surface is most likely responsible for the efficient production of S(1D). For vibrationally excited CH3S(X), a viable mechanism for the dominant production of S(1D) may involve direct dissociation via the CH3S (E2E) state formed in the 193 nm photoexcitation. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. GRINNELL COLL,DEPT PHYS,GRINNELL,IA 50112. RP HSU, CW (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 42 TC 33 Z9 34 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 1 PY 1992 VL 97 IS 9 BP 6283 EP 6290 DI 10.1063/1.463690 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500035 ER PT J AU BINTZ, KL THOMPSON, DL GOSNELL, TR HAY, PJ AF BINTZ, KL THOMPSON, DL GOSNELL, TR HAY, PJ TI INTRAMOLECULAR AND DISSOCIATION DYNAMICS OF THE CF2BR RADICAL SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CIS-TRANS-ISOMERIZATION; MODE SPECIFICITY; ENERGY-TRANSFER; SPECTRA; DECOMPOSITION; SPECTROSCOPY; SYSTEMS; HONO AB Classical trajectory methods were used to investigate the nature of the intramolecular dynamics (quasiperiodic vs chaotic) of the CF2Br radical. The potential energy surface is based on empirical and ab initio results. Power spectra show that the Br-C-F bend exhibits quasiperiodic dynamics while the other modes are chaotic. Despite the presence of quasiperiodic dynamics, the dissociation rates for mode-specific excitations of the normal modes are essentially the same as those for equipartitioning of the excitation energy among all the normal modes. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP BINTZ, KL (reprint author), OKLAHOMA STATE UNIV,DEPT CHEM,STILLWATER,OK 74078, USA. NR 37 TC 9 Z9 9 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 1 PY 1992 VL 97 IS 9 BP 6432 EP 6442 DI 10.1063/1.463701 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500047 ER PT J AU JAKUBETZ, W SOKOLOVSKI, D CONNOR, JNL SCHATZ, GC AF JAKUBETZ, W SOKOLOVSKI, D CONNOR, JNL SCHATZ, GC TI COMPARISON OF QUASI-CLASSICAL AND QUANTUM DYNAMICS FOR RESONANCE SCATTERING IN THE CL+HCL-]CLH+CL REACTION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SUDDEN DISTORTED-WAVE; POTENTIAL-ENERGY SURFACE; INTEGRAL CROSS-SECTIONS; OSCILLATING REACTIVITY; H+D2 REACTION; + CL; DISTRIBUTIONS; O+HCL->OH+CL; EXCITATION; STATES AB We present the results of quasiclassical trajectory (QCT) and quantum centrifugal sudden hyperspherical (CSH) scattering calculations for the Cl + HCl --> ClH + Cl reaction using a semiempirical potential energy surface. In particular, we report state-to-state integral and differential cross sections in the vicinity of a transition state resonance that occurs at a total energy E of 0.642 eV. This resonance, which is labeled by the transition state quantum numbers (0,0,2), strongly perturbs the cross sections for the initial rovibrational state HCl(v = 1, j = 5), which was therefore considered in all our calculations. For E greater-than-or-equal-to 0.680 eV, which is well removed from the resonance energy, the QCT and CSH results are in good agreement, but for E near the resonance energy, important quantum effects are found in the integral cross sections, product state distributions, and differential cross sections. The CSH integral cross sections show smooth steplike increases for E almost-equal-to 0.642 eV, which are not seen in the QCT results. Associated with these steps are increased branching to the v'=0 product HCI vibrational state, and a strong propensity for the production of rotational states with j'=15 and 16 for v'=0. These features of the product energy partitioning are not present in the QCT results, although the correct rotational distributions are approximately recovered if the final vibrational action is constrained to match its quantum value. The CSH differential cross sections show a sudden shift from backward to sideward scattering between 0.642 and 0.660 eV, while the QCT cross sections remain backward peaked. An analysis of the "number of atom-diatom encounters," during the course of a reactive collision, shows that there are chattering trajectories. These are associated with sideward scattering, but their probability is low and as a result they do not produce distinct features in the angular distributions. However, if the classical deflection function is weighted by the quantum reaction probability, angular distributions are obtained that are in reasonable agreement with the CSH angular distributions (including resonance features). C1 UNIV MANCHESTER, DEPT CHEM, MANCHESTER M13 9PL, LANCS, ENGLAND. ARGONNE NATL LAB, THEORET CHEM GRP, ARGONNE, IL 60439 USA. RP JAKUBETZ, W (reprint author), UNIV VIENNA, INST THEORET CHEM & STRAHLENCHEM, A-1090 VIENNA, AUSTRIA. NR 39 TC 22 Z9 22 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 NOV 1 PY 1992 VL 97 IS 9 BP 6451 EP 6459 DI 10.1063/1.463703 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500049 ER PT J AU CHIU, SW LI, WK TZENG, WB NG, CY AF CHIU, SW LI, WK TZENG, WB NG, CY TI A GAUSSIAN-2 ABINITIO STUDY OF CH2SH, CH2S-, CH3S-, CH2SH-, CH3SH-, CH3+, AND CH3SH+ SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LASER-INDUCED FLUORESCENCE; MOLECULAR-ENERGIES; RADIATIVE LIFETIMES; 2ND-ROW COMPOUNDS; DIMETHYL SULFIDE; PHOTOIONIZATION; METHANETHIOL; SPECTROSCOPY; RADICALS; PHOTODISSOCIATION AB Using the Gaussian-2 (G2) theoretical procedure, we have examined the molecular structures and total energies for CH2SH, CH2S-, CH3S-, CH2SH-, CH3SH-, CH3+, and CH3SH+. Contrary to the relative stabilities of CH3S+ (C3v;3A2) and CH2SH+ (Cs;1A'), the methylthio radical CH3S (Cs;2A') and the methylthio anion CH3S- (C3v;1A1) are predicted to be more stable than the mercaptomethyl radical CH2SH (C1;2A) and the mercaptomethyl anion CH2SH- (Cs;1A') by 9.2 and 3 8.0 kcal/mol, respectively. The CH2SH- (Cs;1A') anion may exist in the cis configuration or the less stable trans structure. Combined with the result of previous G2 calculations, this calculation yields predictions for the adiabatic ionization energies (IE) of CH3 (9.79 eV), CH2SH (7.41 eV), and CH3SH (9.55 eV), which are in accord with the experimental IEs of 9.84 eV for CH3, 7.536 +/- 0.003 eV for CH2SH, and 9.440 eV for CH3SH. The G2 values for the adiabatic electron affinities (EA) of CH2S, CH2SH to trans-CH2SH- (Cs;1A'), CH2SH to cis-CH2SH- (Cs;1A'), and CH3S are 0. 3 8, 0.52 0.61, and 1.86 eV, respectively. The EA(G2)'s of CH2S and CH3S also agree with the respective experimental values of 0.465 +/- 0.023, and 1.861 +/- 0.004 eV. We find that CH3SH- is unstable with respect to the electron detachment channel CH3SH+e-. C1 UNIV ILLINOIS,NATL CTR SUPERCOMP APPLICAT,CHAMPAIGN,IL 61820. CHINESE UNIV HONG KONG,DEPT CHEM,SHA TIN,HONG KONG. ACAD SINICA,INST ATOM & MOLEC SCI,TAIPEI 10706,TAIWAN. US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP CHIU, SW (reprint author), UNIV ILLINOIS,CTR BIOTECHNOL,URBANA,IL 61801, USA. RI Tzeng, Wen-Bih/F-7926-2012 NR 53 TC 79 Z9 79 U1 3 U2 7 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 NOV 1 PY 1992 VL 97 IS 9 BP 6557 EP 6568 DI 10.1063/1.463659 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500062 ER PT J AU LEE, TJ ROHLFING, CM RICE, JE AF LEE, TJ ROHLFING, CM RICE, JE TI AN EXTENSIVE ABINITIO STUDY OF THE STRUCTURES, VIBRATIONAL-SPECTRA, QUADRATIC FORCE-FIELDS, AND RELATIVE ENERGETICS OF 3 ISOMERS OF CL2O2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID GAUSSIAN-BASIS SETS; CHLORINE OXIDE DIMER; ATOMIC BASIS SETS; FIRST-ROW ATOMS; MOLECULAR CALCULATIONS; HYDROGEN-PEROXIDE; INFRARED-SPECTRUM; OZONE DEPLETION; TRIPLE EXCITATIONS; TRANSITION-STATE AB The three lowest-lying isomers Of Cl2O2 have been investigated using state-of-the-art ab initio quantum-mechanical methods. Electron correlation methods that have been used include second-order Moller-Plesset perturbation theory, singles and doubles coupled-cluster (CCSD) theory, and the CCSD(T) method, which incorporates a perturbational estimate of the effects of connected triple excitations. Accurate relative energies have been obtained using the CCSD(T) method in conjunction with large atomic natural orbital basis sets that include up to g-type functions. Our best estimate is that the ClClO2 and ClOClO isomers lie 0.9 +/- 2.0 and 10.1 +/- 4.0 kcal/mol higher in energy (0 K), respectively, than the more stable ClOOCl peroxide form. In order to obtain accurate equilibrium geometries it is necessary to include f-type functions in the one-particle basis set. The vibrational spectra (including IR intensities) of all three isomers are computed and compared with experimental data for ClOOCl and ClClO2. The theoretical and experimental vibrational frequencies agree very well except for the symmetric combination of Cl-0 stretches in ClOOCl, where it is concluded that the experimental band is most likely due to the antisymmetric Cl-0 stretch. The heat of formation of ClOOCl is computed using an isodesmic reaction involving Cl2O, H2O, and HOOH, and determined to be 34.2 kcal/mol (0 K). The largest uncertainty in this value is due to potential errors in the experimental heat of formation Of Cl2O. Using the experimental heat of formation of CIO, the dissociation energy of ClOOCl relative to 2 CIO is computed to be 14.9 kcal/mol at 298 K. The equilibrium structures and vibrational spectra Of Cl2O, H2O, and HOOH from our highest-level calculations are found to be in excellent agreement with the available experimental data. C1 SANDIA NATL LABS, DIV THEORET, LIVERMORE, CA 94551 USA. IBM CORP, ALMADEN RES CTR, RES DIV, SAN JOSE, CA 95120 USA. RP LEE, TJ (reprint author), NASA, AMES RES CTR, MOFFETT FIELD, CA 94035 USA. RI Rice, Julia/K-4928-2012; Lee, Timothy/K-2838-2012 OI Rice, Julia/0000-0001-5059-5127; NR 66 TC 97 Z9 97 U1 0 U2 0 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 NOV 1 PY 1992 VL 97 IS 9 BP 6593 EP 6605 DI 10.1063/1.463663 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500066 ER PT J AU CURTISS, LA NOBES, RH POPLE, JA RADOM, L AF CURTISS, LA NOBES, RH POPLE, JA RADOM, L TI THEORETICAL-STUDY OF THE ORGANOSULFUR SYSTEMS CSHN (N = 0-4) AND CSHN+ (N = 0-5) - DISSOCIATION-ENERGIES, IONIZATION ENERGIES, AND ENTHALPIES OF FORMATION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID VACUUM ULTRAVIOLET PHOTODISSOCIATION; FRAGMENTATION PROCESSES; PROTON AFFINITIES; RADICAL CATIONS; PHOTOIONIZATION; REARRANGEMENT; METHANETHIOL; MOLECULES; SULFIDE; CH3SH AB The Gaussian-2 (G2) theoretical procedure, based on ab initio molecular orbital theory, is used to calculate the energies of the CSHn (n = 0-4) hydrides and CSHn+ (n = 0-5) cations. The G2 adiabatic ionization energies of CH3SH, CH2SH, CH3S, CH2S, HCS, and CS as well as the proton affinity of CH3SH are all in satisfactory agreement with experimental values. G2 enthalpies of formation of the neutrals and cations have also been calculated and are used to help assess the reliability of the experimental values, which in some cases cover a rather wide range. The calculated enthalpy of formation of CH3S at 0 K is 31.6 kcal/mol. This supports the value of 31.44 kcal/mol reported in a recent kinetics study over values of 34.2-35.5 kcal/mol obtained in recent photofragmentation studies. Theoretical S-H and C-H bond dissociation energies for CH3SH are 86.0 and 95.0 kcal/mol, respectively. G2 theory predicts the CH2SH+ cation to lie 33.1 kcal/mol lower in energy than the CH3S' cation, in good agreement with the value of 33.5 +/- 2 kcal/mol obtained in a recent photoionization study, but differing significantly from results of previous experimental work that gave a much larger energy difference. The G2 enthalpies of formation at 0 K of CH2S, CH2S+, HCS, and HCS+ are calculated to be 28.7, 245.0, 70.8, and 241.7 kcal/mol, respectively. C1 CARNEGIE MELLON UNIV,DEPT CHEM,PITTSBURGH,PA 15213. AUSTRALIAN NATL UNIV,RES SCH CHEM,CANBERRA,ACT 2601,AUSTRALIA. AUSTRALIAN NATL UNIV,SUPERCOMP FACIL,CANBERRA,ACT 2601,AUSTRALIA. RP CURTISS, LA (reprint author), ARGONNE NATL LAB,DIV MAT SCI,DIV CHEM TECHNOL,ARGONNE,IL 60439, USA. NR 37 TC 94 Z9 97 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 NOV 1 PY 1992 VL 97 IS 9 BP 6766 EP 6773 DI 10.1063/1.463654 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JX295 UT WOS:A1992JX29500088 ER PT J AU VOLKOW, ND TANCREDI, L AF VOLKOW, ND TANCREDI, L TI CURRENT AND FUTURE APPLICATIONS OF SPECT IN CLINICAL-PSYCHIATRY SO JOURNAL OF CLINICAL PSYCHIATRY LA English DT Article; Proceedings Paper CT SYMP ON CLINICAL APPLICATIONS OF NEUROSPECT IN PSYCHIATRY, AT THE 145TH ANNUAL MEETING OF THE AMERICAN PSYCHIATRIC ASSOCIATION CY MAY 03, 1992 CL WASHINGTON, DC SP AMER PSYCHIAT ASSOC, MEDI PHYS ID CEREBRAL BLOOD-FLOW; EMISSION COMPUTED-TOMOGRAPHY; RECEPTOR OCCUPANCY; VISUAL-STIMULATION; BRAIN; SCHIZOPHRENIA; PERFUSION; DISEASE; IMP; PET AB Over the past 10 years several studies have been conducted in psychiatric and neurologic patients with single photon emission computed tomography (SPECT) to determine if patterns of brain dysfunction exist that characterize the different mental diseases. Although there has not been any finding that can be referred to as specific for a particular disease, SPECT studies have been able to demonstrate evidence of brain dysfunction in patients who, when tested with other means, showed no evidence of brain abnormalities. In this manuscript, the current and future applications of SPECT in the clinical practice of psychiatry are analyzed. C1 NYU,DEPT PSYCHIAT,NEW YORK,NY 10003. RP VOLKOW, ND (reprint author), BROOKHAVEN NATL LAB,DEPT PSYCHIAT,BLDG 490,UPTON,NY 11973, USA. NR 25 TC 3 Z9 3 U1 0 U2 0 PU PHYSICIANS POSTGRADUATE PRESS PI MEMPHIS PA P O BOX 240008, MEMPHIS, TN 38124 SN 0160-6689 J9 J CLIN PSYCHIAT JI J. Clin. Psychiatry PD NOV PY 1992 VL 53 SU S BP 26 EP 28 PG 3 WC Psychology, Clinical; Psychiatry SC Psychology; Psychiatry GA KC606 UT WOS:A1992KC60600005 PM 1459980 ER PT J AU BURGESS, D SULSKY, D BRACKBILL, JU AF BURGESS, D SULSKY, D BRACKBILL, JU TI MASS MATRIX FORMULATION OF THE FLIP PARTICLE-IN-CELL METHOD SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID FLOW C1 UNIV NEW MEXICO,DEPT MATH & STAT,ALBUQUERQUE,NM 87131. RP BURGESS, D (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 16 TC 71 Z9 71 U1 0 U2 5 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 NOV PY 1992 VL 103 IS 1 BP 1 EP 15 DI 10.1016/0021-9991(92)90323-Q PG 15 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA JV669 UT WOS:A1992JV66900001 ER PT J AU HARLEY, TR CHENG, CZ JARDIN, SC AF HARLEY, TR CHENG, CZ JARDIN, SC TI THE COMPUTATION OF RESISTIVE MHD INSTABILITIES IN AXISYMMETRICAL TOROIDAL PLASMAS SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID TEARING MODES; CYLINDRICAL PLASMAS; STABILITY; TOKAMAKS; EQUILIBRIUM; GEOMETRY; IDEAL C1 PRINCETON UNIV,PLASMA PHYS LAB,PRINCETON,NJ 08543. RI Jardin, Stephen/E-9392-2010; Cheng, Chio/K-1005-2014 NR 33 TC 3 Z9 3 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 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD NOV PY 1992 VL 103 IS 1 BP 43 EP 62 DI 10.1016/0021-9991(92)90325-S PG 20 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA JV669 UT WOS:A1992JV66900003 ER PT J AU TRANGENSTEIN, JA PEMBER, RB AF TRANGENSTEIN, JA PEMBER, RB TI NUMERICAL ALGORITHMS FOR STRONG DISCONTINUITIES IN ELASTIC-PLASTIC SOLIDS SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID HYPERBOLIC CONSERVATION-LAWS; FLUX-CORRECTED TRANSPORT; SCHEMES; FCT RP LAWRENCE LIVERMORE NATL LAB, DIV COMP & MATH RES, L-316, POB 808, LIVERMORE, CA 94550 USA. NR 33 TC 18 Z9 18 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD NOV PY 1992 VL 103 IS 1 BP 63 EP 89 DI 10.1016/0021-9991(92)90326-T PG 27 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA JV669 UT WOS:A1992JV66900004 ER PT J AU BIEFELD, RM GEDRIDGE, RW AF BIEFELD, RM GEDRIDGE, RW TI THE GROWTH OF INSB USING TRIISOPROPYLANTIMONY OR TERTIARYBUTYLDIMETHYLANTIMONY AND TRIMETHYLINDIUM SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON METALORGANIC VAPOR PHASE EPITAXY ( ICMOVPE-VI ) CY JUN 08-11, 1992 CL CAMBRIDGE, MA ID VAPOR-PHASE EPITAXY; MOCVD; GAAS AB The growth of InSb using triisopropylantimony (TIPSb) or tertiarybutyldimethylantimony (TBDMSb) and TMIn was investigated over a temperature range of 350 to 475-degrees-C. The growth rates of InSb using TMIn and either TIPSb or TBDMSb at temperatures less-than-or-equal-to 425-degrees-C were proportional to both the TMIn flow rate and the temperature. The surface morphology of InSb grown using either TIPSb or TBDMSb was very rough for growth temperatures less-than-or-equal-to 425-degrees-C. The InSb with the highest mobility was grown at 400-degrees-C and a 5/3 ratio of 3 using TIPSb. It was n-type with a carrier concentration of 2.5 X 10(15) cm-3 and a mobility of 78,160 cm2/V. s at 77 K. Both n- and p-type InSb were grown using TBDMSb with mobilities up to 67,530 and 7773 cm2/V.s, respectively at 77 K. The mobility for InSb using either TIPSb or TBDMSb was optimized by going to lower temperatures, pressures and 5/3 ratios. The opposite was true for surface morphology which improved with higher temperature, pressure, and 513 ratio. The growth of high mobility InSb with smooth surfacestat T less-than-or-equal-to 425-degrees-C was not achievable with TIPSb or TBDMSb and TMIn. C1 USN,CTR AIR WARFARE,CHINA LAKE,CA 93555. RP BIEFELD, RM (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 18 TC 15 Z9 15 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 1992 VL 124 IS 1-4 BP 150 EP 157 DI 10.1016/0022-0248(92)90452-O PG 8 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KB905 UT WOS:A1992KB90500025 ER PT J AU BIEFELD, RM KURTZ, SR CASALNUOVO, SA AF BIEFELD, RM KURTZ, SR CASALNUOVO, SA TI REPRODUCIBLE GROWTH OF INASXSB1-X/INSB STRAINED-LAYER SUPERLATTICE PHOTODIODES BY LOW-PRESSURE MOCVD SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON METALORGANIC VAPOR PHASE EPITAXY ( ICMOVPE-VI ) CY JUN 08-11, 1992 CL CAMBRIDGE, MA ID MISFIT DISLOCATION MORPHOLOGY; MOLECULAR-BEAM EPITAXY; ZINCBLENDE STRUCTURE; GAAS; SEMICONDUCTORS; IMMOBILIZATION; GENERATION; VELOCITY AB Reproducible growth of InAsxSb1-x/InSb strained-layer superlattice photodiodes by low pressure metalorganic chemical vapor deposition (MOCVD) has resulted from the use of Zn doped InAsxSb1-x step-graded buffer layers. These photodiodes show improved performance with response to 10 mum and detectivities of 4 X 10(9) cm Hz1/2/W at 6 mum. Dislocation formation in InAsxSb1-x buffer layers grown on InSb substrates by MOCVD is shown to be reproducibly enhanced by p-type doping at levels exceeding the intrinsic carrier concentration at 475-degrees-C using diethylzinc. Carrier concentrations up to 6 x 10(18) cm-3 were obtained. The Zn doped buffer layers have proven to be reproducibly crack free for InAsxSb1-x step graded buffer layers with a final composition of x = 0.12 lattice matched to a strained layer superlattice (SLS) with an average composition of x = 0.09. RP BIEFELD, RM (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 20 TC 14 Z9 14 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 1992 VL 124 IS 1-4 BP 401 EP 408 DI 10.1016/0022-0248(92)90491-Z PG 8 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KB905 UT WOS:A1992KB90500064 ER PT J AU HANNA, MC LU, ZH OH, EG MAO, E MAJERFELD, A AF HANNA, MC LU, ZH OH, EG MAO, E MAJERFELD, A TI INTRINSIC CARBON INCORPORATION IN VERY HIGH-PURITY MOVPE GAAS SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON METALORGANIC VAPOR PHASE EPITAXY ( ICMOVPE-VI ) CY JUN 08-11, 1992 CL CAMBRIDGE, MA ID CHEMICAL VAPOR-DEPOSITION; PHASE EPITAXY; TRIMETHYLGALLIUM; GROWTH; IMPURITIES; ARSINE; MOBILITY; MOCVD; DONOR AB The limits of intrinsic carbon incorporation in very high purity GaAs grown by atmospheric pressure metalorganic vapor phase epitaxy (MOVPE) were investigated by using a MOVPE system designed specifically for high purity growth along with many sources of highly purified trimethylgallium (TMG) and arsine. We have systematically grown series of layers while varying the growth temperature, gas phase stoichiometry (V/III ratio) and growth rate. In addition we studied the effects of in situ arsine purification on impurity incorporation. Donor and acceptor densities were reliably determined from fitting the temperature dependence of the electron density and mobility. Lineshape analysis of donor to acceptor photoluminescence transitions provided the relative amounts of carbon and zinc acceptors. This work determined a baseline for the minimum carbon incorporation of N(C) greater-than-or-equal-to 5 X 10(13) cm-3, and in addition, achieved a new standard for the electron mobility in n-type GaAs grown with TMG and AsH3 with a peak mobility of mu(48 K) = 213,000 cm2/V.S. Carbon incorporation showed a -1.3 power law dependence on the V/III ratio and was found to be controlled by processes with opposite temperature dependencies at high and low temperatures, thereby reaching a minimum around T(g) = 640 +/- 20-degrees-C. C1 UNIV COLORADO,DEPT ELECT & COMP ENGN,BOULDER,CO 80309. RP HANNA, MC (reprint author), NREL,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 20 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 1992 VL 124 IS 1-4 BP 443 EP 448 DI 10.1016/0022-0248(92)90498-8 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KB905 UT WOS:A1992KB90500071 ER PT J AU KURTZ, SR OLSON, JM KIBBLER, AE BERTNESS, KA AF KURTZ, SR OLSON, JM KIBBLER, AE BERTNESS, KA TI INCORPORATION OF ZINC IN MOCVD GROWTH OF GA0.5IN0.5P SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON METALORGANIC VAPOR PHASE EPITAXY ( ICMOVPE-VI ) CY JUN 08-11, 1992 CL CAMBRIDGE, MA ID CHEMICAL VAPOR-DEPOSITION; PHASE EPITAXY; ZN; GAAS; SURFACE; MOVPE AB Data are presented for the Zn doping of Ga0.5In0.5P, showing that the hole and zinc concentrations increase almost linearly with zinc flow, and also increase with the V/III ratio and with growth rate at a fixed V/III ratio. These observations are consistent with other reports that show the incorporation of zinc to increase with V/III ratio for both GaAs and Gao.5In0.5P deposition by metalorganic chemical vapor deposition (MOCVD). The growth-rate dependence of the zinc incorporation in Ga0.5In0.5P has not previously been reported. A model based on varying group V coverage of the step where zinc is most strongly bound is presented and compared with the data. The model predicts that the zinc incorporation increases with increasing phosphorus overpressure, but should be independent of group III overpressure in the parameter space investigated here. RP KURTZ, SR (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 16 TC 6 Z9 6 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 1992 VL 124 IS 1-4 BP 463 EP 469 DI 10.1016/0022-0248(92)90501-9 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KB905 UT WOS:A1992KB90500074 ER PT J AU ARNOLD, J WALKER, JM YU, KM BONASIA, PJ SELIGSON, AL BOURRET, ED AF ARNOLD, J WALKER, JM YU, KM BONASIA, PJ SELIGSON, AL BOURRET, ED TI GROWTH OF II-VI THIN-FILMS FROM SINGLE-SOURCE PRECURSORS BASED ON STERICALLY ENCUMBERED SITEL LIGANDS SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON METALORGANIC VAPOR PHASE EPITAXY ( ICMOVPE-VI ) CY JUN 08-11, 1992 CL CAMBRIDGE, MA AB We have developed a new route to MOCVD of II-VI compounds based on the use of novel single-source precursors in which the II-VI elements are combined at the molecular level in a single covalent compound. We have prepared and fully characterized a number of new derivatives of zinc, cadmium and mercury incorporating large, sterically demanding tellurolate ligands of general formula: M(sitel)2 where sitel = -TeSi(SiMe3)3. The crystalline compounds are relatively volatile and are easily manipulated under nitrogen. Several of these compounds have been tested for their suitability as precursors in the MOCVD process. Clean pyrolysis reactions and deposition of thin films were achieved. The stoichiometry of the pyrolysis reaction has been determined by analysis of the reaction by-products. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RP ARNOLD, J (reprint author), LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720, USA. RI Yu, Kin Man/J-1399-2012; Arnold, John/F-3963-2012 OI Yu, Kin Man/0000-0003-1350-9642; Arnold, John/0000-0001-9671-227X NR 10 TC 50 Z9 50 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 1992 VL 124 IS 1-4 BP 647 EP 653 DI 10.1016/0022-0248(92)90531-M PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KB905 UT WOS:A1992KB90500104 ER PT J AU ERBIL, A BRAUN, W KWAK, BS WILKENS, BJ BOATNER, LA BUDAI, JD AF ERBIL, A BRAUN, W KWAK, BS WILKENS, BJ BOATNER, LA BUDAI, JD TI OXIDE FERROELECTRIC MATERIALS GROWN BY METALORGANIC CHEMICAL VAPOR-DEPOSITION SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON METALORGANIC VAPOR PHASE EPITAXY ( ICMOVPE-VI ) CY JUN 08-11, 1992 CL CAMBRIDGE, MA ID PBTIO3 THIN-FILMS; YBA2CU3O7-DELTA AB Various ferroelectric perovskite-type oxides have been successfully grown by using the metalorganic chemical vapor deposition technique. In particular, the results obtained for the growth of PbTiO3, BaTiO3, and PZT are reported. PbTiO3 thin films grown on fused quartz and Si(100) were polycrystalline and were fully textured with the a- and c-axes perpendicular to the surface. Epitaxy was achieved on the (001) surfaces of the single crystals KTaO3, SrTiO3, and MgO. The MOCVD process and thin-film properties are discussed along with our recent work on the prediction of thin-film properties by using a Landau-Ginzburg-Devonshire type free-energy functional. The ferroelectric properties and domain orientation of epitaxial PbTiO3 thin films strongly depend on the substrate used and on film thickness in the range of 200-8000 angstrom. The spontaneous polarization decreased with decreasing thickness for films grown on KTaO3. The films grown on KTaO3 consist of periodic alternating a- and c-domains with 90-degrees domain walls making an angle of about 45-degrees with the surface. C1 BELL COMMUN RES INC,RED BANK,NJ 07701. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. RP ERBIL, A (reprint author), GEORGIA INST TECHNOL,SCH PHYS,ATLANTA,GA 30332, USA. RI Boatner, Lynn/I-6428-2013; Budai, John/R-9276-2016 OI Boatner, Lynn/0000-0002-0235-7594; Budai, John/0000-0002-7444-1306 NR 19 TC 30 Z9 31 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 1992 VL 124 IS 1-4 BP 684 EP 689 DI 10.1016/0022-0248(92)90536-R PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KB905 UT WOS:A1992KB90500109 ER PT J AU SCHNEIDER, RP BRYAN, RP LOTT, JA JONES, ED OLBRIGHT, GR AF SCHNEIDER, RP BRYAN, RP LOTT, JA JONES, ED OLBRIGHT, GR TI MOVPE GROWTH OF INALGAP-BASED VISIBLE VERTICAL-CAVITY SURFACE-EMITTING LASERS SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 6TH INTERNATIONAL CONF ON METALORGANIC VAPOR PHASE EPITAXY ( ICMOVPE-VI ) CY JUN 08-11, 1992 CL CAMBRIDGE, MA ID VAPOR-PHASE EPITAXY; BAND-GAP ENERGY; OPTICAL-PROPERTIES; ALLOYS; PHOTOLUMINESCENCE; GA0.5IN0.5P; GAINP AB Materials growth issues for visible vertical-cavity surface-emitting lasers have been addressed in detail. For high optical efficiency in the laser cavity, the optical properties of In0.48(AlyGa1-y)0.52P quarternary alloys lattice-matched to GaAs were optimized as a function of MOVPE growth parameters including substrate temperature and misorientation. The narrowest photoluminescent linewidths yet reported for all of the direct bandgap ln(AlyGa1-y)P alloys (0 less-than-or-equal-to y less-than-or-equal-to 0.5)were observed, including 4.2 meV for InGaP. The growth and optical properties of strained quantum well structures were then investigated for use in the laser active region. Structures with a broad range of well and barrier compositions and thicknesses were prepared, and characterized using low-temperature photoluminescence. Based upon this work, high-optical quality strained and unstrained multiple-quantum-well heterostructures were grown for use in the 640-670 nm wavelength range. Epitaxial multilayer dielectric mirror stacks reflecting at visible (620-700 nm) wavelengths were fabricated from the Al0.5Ga0.5As/AlAs and InGaP/InP systems, and for both types of mirrors excellent reflectivity characteristics were observed. Visible VCSEL structures were grown for photopumping experiments, and the structures exhibited low threshold powers. Wavelength of operation of these structures was in the range 632-661nm. C1 PHOTON RES INC,BROOMFIELD,CO. RP SCHNEIDER, RP (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 25 TC 23 Z9 23 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 1992 VL 124 IS 1-4 BP 763 EP 771 DI 10.1016/0022-0248(92)90549-X PG 9 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA KB905 UT WOS:A1992KB90500122 ER PT J AU MCINTOSH, MJ AF MCINTOSH, MJ TI THE EFFECT OF PARTICLE FEED RATE ON THE PLASTIC MEDIA BLAST JET SO JOURNAL OF ENGINEERING FOR INDUSTRY-TRANSACTIONS OF THE ASME LA English DT Article AB Paint removal from military aircraft is often done by plastic media blasting (PMB): the use of plastic grit in a conventional blast jet. However, there is some concern that PMB will cause damage. To help in evaluating this possibility, a "time of flight" meter is used to measure particle velocity in the jet, as a function of air pressure, distance from the nozzle, and particle feed rate, F. Using the data and a momentum balance, a semi-empirical model relating these variables is developed and used for analysis of the effect of F on the intensity of kinetic energy delivery, E, to a work piece. The analysis shows that F has several important effects on E. These methods and results will be useful for damage studies and in production work. RP MCINTOSH, MJ (reprint author), ARGONNE NATL LAB,DIV ENERGY SYST,ARGONNE,IL 60439, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-0817 J9 J ENG IND-T ASME JI J. Eng. Ind.-Trans. ASME PD NOV PY 1992 VL 114 IS 4 BP 435 EP 440 PG 6 WC Engineering, Mechanical SC Engineering GA KA741 UT WOS:A1992KA74100009 ER PT J AU PARK, YJ AF PARK, YJ TI EQUIVALENT LINEARIZATION FOR SEISMIC RESPONSES .1. FORMULATION AND ERROR ANALYSIS SO JOURNAL OF ENGINEERING MECHANICS-ASCE LA English DT Article ID HYSTERETIC SYSTEMS; RANDOM VIBRATION AB A random-vibration approach for uniaxial and biaxial nonlinear structures is presented based on the stochastic equivalent-linearization method. By modifying and combining existing modeling techniques, a unified hysteretic modeling scheme is proposed. The method is applicable both to conventional uniaxial systems and general orthotropic systems, i.e., structural systems having different nonlinear characteristics in different directions. A significant attention is directed to the numerical errors associated with the equivalent-linearization approximation. Numerical errors are classified as stationary and nonstationary errors. The mechanism of each error is carefully studied and quantitatively evaluated through a series of parametric studies. The postyield stiffness ratio, alpha, has been singled out as a key parameter in the error analysis. A practical error-correction scheme is presented based on a large number of simulations. RP PARK, YJ (reprint author), BROOKHAVEN NATL LAB,DEPT NUCL ENERGY,UPTON,NY 11973, USA. NR 18 TC 11 Z9 13 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9399 J9 J ENG MECH-ASCE JI J. Eng. Mech.-ASCE PD NOV PY 1992 VL 118 IS 11 BP 2207 EP 2226 DI 10.1061/(ASCE)0733-9399(1992)118:11(2207) PG 20 WC Engineering, Mechanical SC Engineering GA JU032 UT WOS:A1992JU03200004 ER PT J AU DARWIN, RF AF DARWIN, RF TI NATURAL-RESOURCES AND THE MARSHALLIAN EFFECTS OF INPUT-REDUCING TECHNOLOGICAL CHANGES SO JOURNAL OF ENVIRONMENTAL ECONOMICS AND MANAGEMENT LA English DT Article C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. RP DARWIN, RF (reprint author), USDA, ECON RES SERV, ROOM 408, 1301 NEW YORK AVE NW, WASHINGTON, DC 20005 USA. NR 27 TC 3 Z9 3 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 0095-0696 J9 J ENVIRON ECON MANAG JI J.Environ.Econ.Manage. PD NOV PY 1992 VL 23 IS 3 BP 201 EP 215 DI 10.1016/0095-0696(92)90001-D PG 15 WC Business; Economics; Environmental Studies SC Business & Economics; Environmental Sciences & Ecology GA KA261 UT WOS:A1992KA26100001 ER PT J AU GOPALRATNAM, VC BENNETT, GF PETERS, RW AF GOPALRATNAM, VC BENNETT, GF PETERS, RW TI EFFECT OF COLLECTOR DOSAGE ON METAL REMOVAL BY PRECIPITATION FLOTATION SO JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE LA English DT Article ID HEAVY-METALS; SEPARATION AB This study examined the effects of various dosages of chemical collectors on the removal in a combined metal hydroxide precipitation and air-flotation of heavy metals from industrial wastewaters. The residual metal concentrations were sensitive to pH, collector dosage, and air-injection rate. The optimum pH for treatment of the industrial wastewaters was 9.18, determined from jar tests. Although this pH does not necessarily represent the maximum removal of any one metal, it represented the optimal removal of the combined metals system. A single collector dosage did not maximize the removal of each metal from the industrial wastewaters used in the study. Metal removals were slightly greater using the nozzle air flotation system as compared to the induced air flotation system. The study also found that a single collector dosage is not effective for all metals, although removals of more than 80% were consistently achieved. The removal of heavy metals and oil appears to occur through a coprecipitation-adsorption mechanism. C1 PURDUE UNIV,SCH CIV ENGRG,W LAFAYETTE,IN 47907. UNIV TOLEDO,DEPT CHEM ENGRG,TOLEDO,OH 43606. ARGONNE NATL LAB,DIV ENERGY SYST,ARGONNE,IL 60439. RP GOPALRATNAM, VC (reprint author), PAYNE RIEMER GRP INC,8260 NORTHCREEK DR,STE 300,CINCINNATI,OH 45236, USA. NR 38 TC 4 Z9 4 U1 0 U2 2 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9372 J9 J ENVIRON ENG-ASCE JI J. Environ. Eng.-ASCE PD NOV-DEC PY 1992 VL 118 IS 6 BP 923 EP 948 DI 10.1061/(ASCE)0733-9372(1992)118:6(923) PG 26 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA JZ467 UT WOS:A1992JZ46700007 ER PT J AU HUANG, CS CIESLA, JJ AF HUANG, CS CIESLA, JJ TI LESSONS LEARNED FROM THE ON-SITE DISTILLATION OF USED SOLVENTS GENERATED BY HEALTH-CARE FACILITIES SO JOURNAL OF ENVIRONMENTAL HEALTH LA English DT Article AB This paper discusses the sources of contaminants found in used solvents generated by the histopathological laboratories at health care facilities, and the technical problems, corrective measures and economic analysis associated with the on-site recycling and reusing of these used solvents. Commercially available, small-scale solvent distillation units were evaluated at two U.S. Army health care facilities to determine whether used xylene, ethanol and citrus-based laboratory solvents could be effectively recycled. These used solvents were distilled under vacuum and atmospheric pressure. It was demonstrated that xylene and citrus-based solvents could be effectively recycled by distillation at atmospheric pressure. Ethanol, however, required vacuum distillation to produce a recycled product of acceptable quality. In addition to the environmental benefits, economic analysis indicated that recycling can save money when compared with the cost of disposal by contractors. RP HUANG, CS (reprint author), US DOE,OFF ENVIRONM AUDIT,EH-24,1000 INDEPENDENCE AVE SW,WASHINGTON,DC 20585, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NATL ENVIRON HEALTH ASSN PI DENVER PA 720 S COLORADO BLVD SUITE 970, SOUTH TOWER, DENVER, CO 80222 SN 0022-0892 J9 J ENVIRON HEALTH JI J. Environ. Health PD NOV-DEC PY 1992 VL 55 IS 3 BP 26 EP 30 PG 5 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA JW907 UT WOS:A1992JW90700006 ER PT J AU BASARAN, OA WOHLHUTER, FK AF BASARAN, OA WOHLHUTER, FK TI EFFECT OF NONLINEAR POLARIZATION ON SHAPES AND STABILITY OF PENDANT AND SESSILE DROPS IN AN ELECTRIC (MAGNETIC) FIELD SO JOURNAL OF FLUID MECHANICS LA English DT Article ID DROPLETS AB Axisymmetric shapes and stability of nonlinearly polarizable dielectric (ferrofluid) drops of fixed volume which are pendant/sessile on one plate of a parallel-plate capacitor and are subjected to an applied electric (magnetic) field are determined by solving simultaneously the free boundary problem comprised of the Young-Laplace equation for drop shape and the Maxwell equations for electric (magnetic) field distribution. Motivated by the desire to explain certain experiments with ferrofluids, a constitutive relation often used to describe the variation of polarization with applied field strength is adopted here to close the set of equations that govern the distribution of electric field. Specifically, the nonlinear polarization, P, is described by a Langevin equation of the form P = alpha[coth (tauE) - 1/(tauE)], where E is the electric field strength. As expected, the results show that nonlinearly polarizable drops behave similarly to linearly polarizable drops at low field strengths when drop deformations are small. However, it is demonstrated that at higher values of the field strength when drop deformations are substantial, nonlinearly polarizable supported drops whose contact lines are fixed, as well as ones whose contact angles are prescribed, display hysteresis in drop deformation over a wide range of values of the Langevin parameters alpha and tau. Indeed, properly accounting for the nonlinearity of the polarization improves the quantitative agreement between theory and the experiments of Bacri et al. (1982) and Bacri & Salin (1982, 1983). Detailed examination of the electric fields inside nonlinearly polarizable supported drops reveals that they are very non-uniform, in contrast to the nearly uniform fields usually found inside linearly polarizable drops. C1 UNIV TENNESSEE,DEPT CHEM ENGN,KNOXVILLE,TN 37996. RP BASARAN, OA (reprint author), OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831, USA. NR 17 TC 32 Z9 32 U1 0 U2 7 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD NOV PY 1992 VL 244 BP 1 EP 16 DI 10.1017/S0022112092002945 PG 16 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA JZ760 UT WOS:A1992JZ76000001 ER PT J AU BIRN, J AF BIRN, J TI QUASI-STEADY CURRENT SHEET STRUCTURES WITH FIELD-ALIGNED FLOW SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID TRAVELING COMPRESSION REGIONS; DEEP GEOMAGNETIC TAIL; DISTANT MAGNETOTAIL; BOUNDARY-LAYER; PLASMA; ISEE-3 AB General properties of field-aligned plasma flow in quasi-steady ideal MHD configurations are discussed, and explicit solutions, modeling compressible flow around a plasmoid in the distant magnetotail, are presented. The explicit solutions axe based on the assumption that plasma and field gradients along the x and y directions parallel to the tail current sheet axe typically much smaller than those in the z direction perpendicular to the current sheet. In contrast to the incompressible case, two different flow solutions exist in the compressible case in the subalfvenic regime. The different regimes are distinguished by whether the flow speed is below or above a critical speed v(o), which represents the group velocity of a slow magnetosonic wave (aligned with the magnetic field) in the limit of phase propagation perpendicular to the magnetic field, where the phase speed vanishes. In the incompressible case, only the subcritical flow solution is realized in the subalfvenic regime. In the compressible case, both regimes may exist simultaneously in the flow around the plasmoid. They are separated by a tangential discontinuity which may be considered as the limit of a slow shock for vanishing normal flow and normal magnetic field. The subcritical flow region surrounding the plasmoid inside of a supercritical region possibly corresponds to the layers of tailward streaming ions observed adjacent to the plasmoid proper. The signatures of a passage from the supercritical through the subcritical flow region in the vicinity of the plasmoid can be similar to those of a passage through the plasmoid itself. a reduction of B(x) followed by a local enhancement in the middle of the encounter, as observed, for instance, by Hones et al. (1984) and Slavin et al. (1989). This enhancement is found for a simple loop structure within the plasmoid and hence need not be associated with multiple loops or a tail flapping as suggested by Hones et al. Field signatures outside the plasmoid are typically those of encounters of a traveling compression region: an enhancement of B(x) accompanying a north-south signature of B(z). In certain parameter regimes, however, unusual signatures axe also possible: a reduction of B(x) with a north-south B(z) signature for a close plasmoid encounter (without penetration) and a south-north signature of B(z) accompanying a B(x) enhancement for a distant plasmoid encounter at high latitudes. RP BIRN, J (reprint author), LOS ALAMOS NATL LAB,MS D438,LOS ALAMOS,NM 87545, USA. NR 20 TC 16 Z9 16 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD NOV 1 PY 1992 VL 97 IS A11 BP 16817 EP 16826 DI 10.1029/92JA01527 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX753 UT WOS:A1992JX75300006 ER PT J AU BELIAN, RD GISLER, GR CAYTON, T CHRISTENSEN, R AF BELIAN, RD GISLER, GR CAYTON, T CHRISTENSEN, R TI HIGH-Z ENERGETIC PARTICLES AT GEOSYNCHRONOUS ORBIT DURING THE GREAT SOLAR PROTON EVENT SERIES OF OCTOBER 1989 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ABUNDANCES AB Comparatively high levels of 2- to 50-MeV ions of carbon, nitrogen, oxygen, neon, magnesium, silicon, sulphur, and iron have been identified at geosynchronous orbit by the synchronous orbit particle analyzer, the "SOPA" detector, on board the satellite 1989-046, which became operational in September 1989. This detector is described, and time histories of some of the above mentioned ions are given for the solar energetic particle event series of late October 1989. RP BELIAN, RD (reprint author), LOS ALAMOS NATL LAB,DIV SPACE SCI & TECHNOL,LOS ALAMOS,NM 87545, USA. NR 19 TC 187 Z9 189 U1 1 U2 8 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 NOV 1 PY 1992 VL 97 IS A11 BP 16897 EP 16906 DI 10.1029/92JA01139 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX753 UT WOS:A1992JX75300014 ER PT J AU WHITE, JE AF WHITE, JE TI GUIDANCE AND TARGETING FOR THE STRATEGIC TARGET SYSTEM SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article AB Guidance algorithms and targeting procedures for the Strategic Target System (STARS) launch vehicle are described. The STARS vehicle is a three-stage booster, based partly on retired Polaris A3 missile assets, which is intended to support development and testing of the Strategic Defense Initiative by delivering target payloads to the vicinity of the Kwajalein Atoll. STARS will be launched from the Kauai Test Facility located on Kauai, Hawaii. The STARS guidance objective is to deliver payloads to a prescribed target location with intercontinental ballistic missile re-entry conditions. The guidance problem is complicated by the fact that all three stages lack thrust termination or other velocity control mechanisms, and by range safety requirements for one or more out-of-plane tums. Mission objectives are achieved with a combination of guidance algorithms. The original Polaris guidance is used during the atmospheric ascent phase. The powered explicit guidance used by the Space Shuttle is later employed to execute an out-of-plane turn and to place the third stage as closely as possible onto the desired coast trajectory. Third-stage guidance is a modified Lambert procedure formulated to eliminate the target miss to off-nominal ascent phase performance. RP WHITE, JE (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 9 TC 5 Z9 5 U1 1 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD NOV-DEC PY 1992 VL 15 IS 6 BP 1313 EP 1319 DI 10.2514/3.11391 PG 7 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA JX062 UT WOS:A1992JX06200001 ER PT J AU JONES, GF PRENGER, FC AF JONES, GF PRENGER, FC TI ANALYSIS OF A SCREEN HEAT-EXCHANGER SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE CONDUCTION; CRYOGENICS; HEAT EXCHANGERS AB Heat transfer in a fluid-to-fluid screen heat exchanger is analyzed from first principles. The screens are treated as an ensemble of pin fins and an empirical heat transfer coefficient accounts for convection heat transfer at the fin surface. Pressure drop and simultaneous axial conduction in the screen matrix and the wall separating the fluid streams are modeled. Expressions are obtained that relate dimensionless length ratios to exchanger effectiveness and pressure drop. The "mesh ratio," defined as the ratio of fin diameter (d) to spacing (s), prevails throughout the results. The key findings are: (1) the existence of an optimal ratio of fin length (a) to fin diameter that maximizes thermal performance (arising from the competition between the fin-length dependent heat transfer coefficient and fin surface area), (2) increasing ald greater than optimal increases exchanger length and reduces pressure drop; for ald less than optimal heat transfer is depressed and pressure drop increased, and (3) the pressure drop is linear with overall Ntu and varies as d-2, (1 + d/s)6, and approximately the square of the mass flow rate per width of exchanger. An exact solution for axial conduction is presented that is valid in the limit of large Ntu and equal fluid capacity rates. Axial conduction is seen to decrease with increasing Ntu and mass flow rates and reduced fin ald ratio. Predictions from the model are validated by comparing with published effectiveness and pressure-drop data. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. RP JONES, GF (reprint author), VILLANOVA UNIV,DEPT MECH ENGN,VILLANOVA,PA 19085, USA. NR 18 TC 4 Z9 4 U1 1 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD NOV PY 1992 VL 114 IS 4 BP 887 EP 892 DI 10.1115/1.2911897 PG 6 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA KA761 UT WOS:A1992KA76100013 ER PT J AU UNAL, C DAW, V NELSON, RA AF UNAL, C DAW, V NELSON, RA TI UNIFYING THE CONTROLLING MECHANISMS FOR THE CRITICAL HEAT-FLUX AND QUENCHING - THE ABILITY OF LIQUID TO CONTACT THE HOT SURFACE SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE BOILING; HIGH-TEMPERATURE PHENOMENA ID POOL AB We investigated the hypothesis that the critical heat flux (CHF) occurs when some point on a heated surface reaches a temperature high enough that liquid can no longer maintain contact at that point, resulting in a gradual but continuous increase in the overall surface temperature for most power-controlled systems. This hypothesis unifies the occurrence of the CHF with the quenching of hot surfaces by relating them to the same concept: the ability of a liquid to contact a hot surface, generally defined as some fraction of the liquid's homogeneous nucleation temperature, depending on the contact angle. The proposed hypothesis about the occurrence of the CHF is investigated through a study of the boiling mechanism of the second transition region of nucleate pool boiling of water on copper. An idealized two-dimensional transient conduction heat transfer model was developed to investigate the heat transfer mechanism. The initial macrolayer thickness on the dry portion of the heater, in the second transition region, was found to be bounded between 0 and 11 mum. The radius of the dry patch varied from 15 to 23 mm (60 and 92 percent of the heater radius, respectively) for initial macrolayer thicknesses of 0 and 11 mum, respectively. The results indicated that the critical liquid-solid contact temperature at the onset of CHF (the surface temperature at the center of the dry patch) must be lower than the homogeneous nucleation temperature of the liquid for the pool boiling of water on a clean horizontal surface. The liquid-solid contact temperature was dependent on the initial dry patch liquid macrolayer thickness, varying from 180-degrees-C to 157-degrees-C for initial macrolayer thicknesses of 0 and 11 mum, respectively. Independent assessment of these values shows good agreement with extrapolated contact temperature data at the onset of film boiling. This indicates that the mechanism for the occurrence of the CHF could be similar to the mechanism generally accepted for the quenching of the hot surfaces. Further study of this mechanism to understand better the observed trends in other experimental results show qualitative agreement with those results. These include a significant decrease in the radius of the dry patch to 4 mm (16 percent of the heater radius) when the thermal conductivity of the heater was decreased to that corresponding to nickel. When the thickness of a copper heater was decreased from 10 mm (representing an infinitely thick medium) to 0.1 mm, a dry patch radius of 2.25 mm (9 percent of the heater radius) was found to be sufficient for the temperature at the center of the dry patch to reach the critical contact temperature. These comparisons are felt to provide some understanding as to why the second transition region has been observed only in limited cases. RP UNAL, C (reprint author), LOS ALAMOS NATL LAB,DIV NUCL TECHNOL & ENGN,ENGN & SAFETY ANAL GRP,LOS ALAMOS,NM 87545, USA. NR 35 TC 28 Z9 28 U1 1 U2 4 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 NOV PY 1992 VL 114 IS 4 BP 972 EP 982 DI 10.1115/1.2911909 PG 11 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA KA761 UT WOS:A1992KA76100025 ER PT J AU GRIFFITHS, SK NILSON, RH AF GRIFFITHS, SK NILSON, RH TI FREEZING FLOW IN A SUBCOOLED PERMEABLE MEDIUM SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE PHASE-CHANGE PHENOMENA; POROUS MEDIA ID POROUS-MEDIA; SYSTEMS AB Analytical similarity solutions are derived for the problem of transient one-dimensional flow and freezing of a liquid in an initially dry Permeable half-space. The structure of the flow consists of three regions: a liquid zone in which the temperature decreases to the freezing temperature, a central two-phase zone where the temperature is at the freezing point, and a leading gas-filled region in which the temperature is nearly undisturbed. The propagation velocity of this intrusion is determined as a function of the subcooling, latent heat, and other process parameters. As the inlet temperature approaches the freezing temperature, the governing equations admit a pair of solutions having propagation velocities that sometimes differ by more than an order of magnitude. C1 S CUBED INC,LA JOLLA,CA 92038. RP GRIFFITHS, SK (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 12 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 NOV PY 1992 VL 114 IS 4 BP 1036 EP 1041 DI 10.1115/1.2911874 PG 6 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA KA761 UT WOS:A1992KA76100032 ER PT J AU ZIMMERMAN, RW CHEN, DW COOK, NGW AF ZIMMERMAN, RW CHEN, DW COOK, NGW TI THE EFFECT OF CONTACT AREA ON THE PERMEABILITY OF FRACTURES SO JOURNAL OF HYDROLOGY LA English DT Article ID FLOW AB The permeability of a rock fracture is controlled primarily by the geometry of its void space. One effect of void space geometry is to cause the fluid to follow a tortuous path to flow around the asperities, which are regions where the two faces of the fracture are in contact. To examine the tortuosity induced by the contact area, we consider an idealized fracture consisting of two parallel plates propped open by isolated asperities. Boundary-element calculations, analogue electrical conductivity measurements and an effective medium approximation are used to study the permeability of fractures with circular, elliptical and irregular asperity shapes. The permeability is seen to depend not only on the amount of contact area, but also on the shape of the asperities. For circular or elliptical asperities, very accurate estimates are found by using the effective medium theory proposed by Maxwell. C1 UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720. RP ZIMMERMAN, RW (reprint author), LAWRENCE BERKELEY LAB,DIV EARTH SCI,BERKELEY,CA 94720, USA. OI Zimmerman, Robert/0000-0001-6674-3403 NR 23 TC 92 Z9 97 U1 1 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD NOV PY 1992 VL 139 IS 1-4 BP 79 EP 96 DI 10.1016/0022-1694(92)90196-3 PG 18 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA KF745 UT WOS:A1992KF74500006 ER PT J AU JOLLY, WL TURNER, JH AF JOLLY, WL TURNER, JH TI COMPUTER-SIMULATION OF THE SABATIER EFFECT SO JOURNAL OF IMAGING SCIENCE AND TECHNOLOGY LA English DT Article AB All of the features of Sabatier solarization, including Sabatier border lines, are represented in the Sabatier H&D curve; that is, they are a consequence of the desensitization in those regions of the emulsion that received a perceptible initial exposure. This point is emphasized by showing that a computer-simulated Sabatier solarization of a black-and-white print (based on a one-to-one correspondence between a normal and a Sabatier-solarized step wedge) and the actual darkroom solarization are very similar. Therefore adjacency effects, such as the Mackie line, are not importantly involved in the Sabatier effect. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP JOLLY, WL (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720, USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU I S & T - SOC IMAGING SCIENCE TECHNOLOGY PI SPRINGFIELD PA 7003 KILWORTH LANE, SPRINGFIELD, VA 22151 SN 8750-9237 J9 J IMAGING SCI TECHN JI J. Imaging Sci. Technol. PD NOV-DEC PY 1992 VL 36 IS 6 BP 558 EP 561 PG 4 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA KE661 UT WOS:A1992KE66100010 ER PT J AU BELLO, AF JISHI, RA AF BELLO, AF JISHI, RA TI LITHOGRAPHIC CHARACTERISTICS OF INORGANIC PHOTORESISTS SO JOURNAL OF IMAGING SCIENCE AND TECHNOLOGY LA English DT Article ID CHARACTERISTIC CURVES; SILVER AB When a bilayer structure composed of a silver layer on a chalcogenide glass film is exposed to light, photoinduced diffusion of silver into the glass takes place, whereupon the photodoped region becomes less soluble in alkaline solutions. The silver concentration profiles in the glass film, as well as the characteristic curves of the inorganic photoresist, are calculated, taking into account the standing-wave effect that arises from the interference of an infinite number of internally reflected waves. It is found that, in the case of large-scale lithography, the standing-wave effect does not lead to any degradation in the lithographic characteristics of the photoresist. C1 LAWRENCE LIVERMORE NATL LAB,LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551. CALIF STATE UNIV LOS ANGELES,DEPT PHYS & ASTRON,LOS ANGELES,CA 90032. RP BELLO, AF (reprint author), UNIV CALIF DAVIS,DEPT APPL SCI,DAVIS,CA 95616, USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU I S & T - SOC IMAGING SCIENCE TECHNOLOGY PI SPRINGFIELD PA 7003 KILWORTH LANE, SPRINGFIELD, VA 22151 SN 8750-9237 J9 J IMAGING SCI TECHN JI J. Imaging Sci. Technol. PD NOV-DEC PY 1992 VL 36 IS 6 BP 562 EP 566 PG 5 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA KE661 UT WOS:A1992KE66100011 ER PT J AU JIN, C LEE, DM LIN, SW SARMA, BK HINKS, DG AF JIN, C LEE, DM LIN, SW SARMA, BK HINKS, DG TI HIGH-RESOLUTION ULTRASOUND STUDIES OF UPT3 AT VERY LOW-TEMPERATURES SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article; Proceedings Paper CT SYMP ON QUANTUM FLUIDS AND SOLIDS CY JUN 15-19, 1992 CL PENN STATE UNIV, UNIVERSITY PARK, PA HO PENN STATE UNIV ID HEAVY-FERMION SUPERCONDUCTORS; MAGNETIC-FIELD; ATTENUATION; ANISOTROPY; TRANSPORT; SOUND AB We have performed longitudinal sound velocity and attenuation measurements on a single crystal of UPt3 between 5 mK and 700 mK. The very low temperatures reached in this experiment allow a better comparison to the theoretical predictions of the longitudinal sound attenuation for different gap states. We have also observed for the first time a significant dispersion of sound associated with the superconducting transition. Within the resolution of our ultrasonic measurements on this sample, we did not observe any manifestation of the recently reported specific heat anomaly around 18 mK1. C1 UNIV WISCONSIN,MILWAUKEE,WI 53201. ARGONNE NATL LAB,ARGONNE,IL 60439. RP JIN, C (reprint author), CORNELL UNIV,ITHACA,NY 14853, USA. NR 16 TC 6 Z9 6 U1 1 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD NOV PY 1992 VL 89 IS 3-4 BP 557 EP 560 DI 10.1007/BF00694086 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA JY743 UT WOS:A1992JY74300034 ER PT J AU FLORENCIO, J SEN, S CAI, ZX AF FLORENCIO, J SEN, S CAI, ZX TI QUANTUM SPIN DYNAMICS OF THE TRANSVERSE ISING-MODEL IN 2 DIMENSIONS SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article; Proceedings Paper CT SYMP ON QUANTUM FLUIDS AND SOLIDS CY JUN 15-19, 1992 CL PENN STATE UNIV, UNIVERSITY PARK, PA HO PENN STATE UNIV ID GENERALIZED LANGEVIN EQUATION; RECURRENCE RELATIONS; RELAXATION FUNCTIONS; CONTINUED-FRACTION; SPECTRA; SYSTEM AB We use the method of recurrence relations to obtain the time-dependent spin correlation function of the Ising model in a transverse field in 2D. We find that the correlation function decays algebraically at long times as t-alpha, where alpha less-than-or-equal-to 2.2. This is to be contrasted with the 1D case where the decay is Gaussian. We expect that in 3D the dynamical correlation will also exhibit a power law decay. Our results can be used to understand the experimental shape functions for the induced moment in LiTbpY1-pF4. C1 MICHIGAN STATE UNIV,DEPT PHYS,E LANSING,MI 48824. BROOKHAVEN NATL LAB,DIV MAT SCI,UPTON,NY 11973. RP FLORENCIO, J (reprint author), PENN STATE UNIV,DEPT PHYS,ALTOONA,PA 16601, USA. NR 16 TC 5 Z9 5 U1 0 U2 2 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD NOV PY 1992 VL 89 IS 3-4 BP 561 EP 564 DI 10.1007/BF00694087 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA JY743 UT WOS:A1992JY74300035 ER PT J AU BULLOCK, GL SHIVARAM, BS HINKS, DG AF BULLOCK, GL SHIVARAM, BS HINKS, DG TI THE ELECTROMAGNETIC RESPONSE OF THE HEAVY ELECTRON SUPERCONDUCTOR URU2SI2 SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article; Proceedings Paper CT SYMP ON QUANTUM FLUIDS AND SOLIDS CY JUN 15-19, 1992 CL PENN STATE UNIV, UNIVERSITY PARK, PA HO PENN STATE UNIV ID UPT3 AB We report measurements of the surface resistance and skin depth in single crystals of the heavy electron superconductor URu2Si2. The measurements were made in all-copper helical resonators in the frequency range 0.19 GHz to 0.54 GHz with the ac field B parallel-to a-axis and the induced current, J, alternately along the a- and c-axes. The surface resistance appears to exhibit the nonexponential behavior expected for a heavy electron superconductor; however, the behavior of the skin depth is more anomalous: The ac magnetic field penetrates more deeply into the superconducting sample at higher frequencies. C1 ARGONNE NATL LABS,DIV MAT SCI & TECHNOL,ARGONNE,IL 60439. RP BULLOCK, GL (reprint author), UNIV VIRGINIA,DEPT PHYS,CHARLOTTESVILLE,VA 22901, USA. NR 10 TC 0 Z9 0 U1 1 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD NOV PY 1992 VL 89 IS 3-4 BP 747 EP 750 DI 10.1007/BF00694132 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA JY743 UT WOS:A1992JY74300080 ER PT J AU MA, H AF MA, H TI THE EQUATORIAL BASIN RESPONSE TO A ROSSBY-WAVE PACKET - THE EFFECTS OF NONLINEAR MECHANISM SO JOURNAL OF MARINE RESEARCH LA English DT Article ID SOLITARY WAVES; PACIFIC-OCEAN; EL-NINO; MODEL; COUNTERCURRENT; CIRCULATION; VARIABILITY; CALIFORNIA; DYNAMICS; VELOCITY AB Responses of the equatorial ocean to a Rossby wave packet, which assumes the form of either a cyclonic or an anticyclonic vortex pair, are simulated with the spectral element shallow water equation model (reduced gravity). We found that during the course of the western boundary reflection of an incoming equatorial Rossby wave packet, strong wave-wave interaction has significant influence on local dynamic and kinetic structures in the western tropical ocean. In the case of the western boundary reflection of a cyclonic Rossby wave vortex pair, the nonlinear effect tends to induce a strong, long-lasting eastward equatorial current; while in the case of the western boundary reflection of an anticyclonic Rossby wave vortex pair, the nonlinear effect significantly weakens movements in the western equatorial region, but greatly enhances the extra-equatorial western boundary currents. Moreover, an extra amount of the energy carried by long waves is permanently lost to short waves due to the strong wave-wave interaction in the western boundary region; therefore, strong nonlinearity has further reduced the effectiveness of the western boundary in reflecting the long Rossby wave signals. The total energy loss through the horizontal eddy viscosity can also be reduced by the strong nonlinear effect. The numerical results show that the phase speeds of the nonlinear equatorial Rossby wave and the nonlinear equatorial Kelvin wave are different from those of the linear waves: the nonlinear waves are faster if the initial Rossby wave packet is an anticyclonic vortex pair which is related to the thermocline deepening, and slower if it is a cyclonic vortex pair which is related to the thermocline shoaling. The simulation with a low Reynolds number shows that high horizontal eddy viscosity can severely suppress the nonlinear activities. The simulation results in the western boundary region with R(e) = 200 are largely explainable by the linear equatorial wave theory. RP MA, H (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,BLDG 515,UPTON,NY 11973, USA. NR 30 TC 6 Z9 6 U1 0 U2 0 PU KLINE GEOLOGY LABORATORY PI NEW HAVEN PA YALE UNIV, NEW HAVEN, CT 06520 SN 0022-2402 J9 J MAR RES JI J. Mar. Res. PD NOV PY 1992 VL 50 IS 4 BP 567 EP 609 DI 10.1357/002224092784797502 PG 43 WC Oceanography SC Oceanography GA KJ790 UT WOS:A1992KJ79000003 ER PT J AU FOX, GR KRUPANIDHI, SB MORE, KL ALLARD, LF AF FOX, GR KRUPANIDHI, SB MORE, KL ALLARD, LF TI COMPOSITION STRUCTURE PROPERTY RELATIONS OF MULTIION-BEAM REACTIVE SPUTTERED LEAD LANTHANUM TITANATE THIN-FILMS .1. COMPOSITION AND STRUCTURE-ANALYSIS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID PBTIO3; CRYSTALLIZATION; TEMPERATURE AB Material properties are greatly dependent upon the structure of the material. This paper, the first of three parts, discusses how composition influences the crystallographic structure and microstructure of lead lanthanum titanate (PLT) thin films grown by the multi-ion-beam reactive sputtering (MIBERS) technique. A transmission electron microscopy (TEM) study detailing the relationship between crystallographic texturing and microstructure development will be presented in a second paper. The dependence of the ferroelectric properties on observed crystallographic structure and microstructure is presented in the third paper of this series. As-deposited PLT microstructures coincide with the structure zone model (SZM) which has been developed to describe the microstructure of thin films deposited by physical vapor deposition. The as-deposited PLT structures are altered during post-deposition annealing as a result of crystallization and PbO evaporation. Amorphous films with more than 10 mole % excess PbO become polycrystalline with porous microstructures after annealing. When there is less PbO in the as-deposited film, (100) texture and dense structures are observed. Porosity results from PbO evaporation, and (100) texture is inhibited by excess PbO. C1 OAK RIDGE NATL LAB,HIGH TEMP MAT LAB,OAK RIDGE,TN 37831. RP FOX, GR (reprint author), PENN STATE UNIV,MAT RES LAB,UNIV PK,PA 16803, USA. RI More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 37 TC 31 Z9 31 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD NOV PY 1992 VL 7 IS 11 BP 3039 EP 3055 DI 10.1557/JMR.1992.3039 PG 17 WC Materials Science, Multidisciplinary SC Materials Science GA JX922 UT WOS:A1992JX92200018 ER PT J AU FABES, BD OLIVER, WC MCKEE, RA WALKER, FJ AF FABES, BD OLIVER, WC MCKEE, RA WALKER, FJ TI THE DETERMINATION OF FILM HARDNESS FROM THE COMPOSITE RESPONSE OF FILM AND SUBSTRATE TO NANOMETER SCALE INDENTATIONS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID WEAR-RESISTANT COATINGS; MECHANICAL-PROPERTIES AB Two equations for determining the hardness of thin films from depth-sensing indentation data are examined. The first equation is based on an empirical fit of hardness versus indenter displacement data obtained from finite element calculations on a variety of hypothetical films. The second equation is based on a model which assumes that measured hardness is determined by the weighted average of the volume of plastically deformed material in the coating and that in the substrate. The equations are evaluated by fitting the predicted hardness versus contact depth to data obtained from titanium coatings on a sapphire substrate. Only the volume fractions model allows the data to be fitted with a single adjustable parameter, the film hardness; the finite element equation requires two thickness-dependent parameters to obtain acceptable fits. It is argued that the difficulty in applying the finite element model lies in the use of an unrealistic area function for the indenter. For real indenters, which have finite radii, the area function must appear explicitly in the final equation. This is difficult to do with the finite element approach, but is naturally incorporated into the volume fractions equation. Finally, using the volume fractions approach the hardnesses of the titanium films are found to be relatively insensitive to film thickness. Thus, the apparent increase in hardness with decreasing film thickness for the titanium films is most likely due to increased interactions between the film and substrate for the thinner films rather than to a change in the basic structure of the titanium films. C1 OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831. RP FABES, BD (reprint author), UNIV ARIZONA,DEPT MAT SCI & ENGN,TUCSON,AZ 85721, USA. NR 14 TC 87 Z9 87 U1 2 U2 14 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 NOV PY 1992 VL 7 IS 11 BP 3056 EP 3064 DI 10.1557/JMR.1992.3056 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA JX922 UT WOS:A1992JX92200019 ER PT J AU EBY, RK EWING, RC BIRTCHER, RC AF EBY, RK EWING, RC BIRTCHER, RC TI THE AMORPHIZATION OF COMPLEX SILICATES BY ION-BEAM IRRADIATION SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID ROCK-FORMING SILICATES; DAMAGE; CERAMICS; QUARTZ; GLASS; TRANSFORMATION; BOMBARDMENT; CHEMISTRY; ELECTRON; DEFECTS AB Twenty-five silicates were irradiated at ambient temperature conditions with 1.5 MeV Kr+. Critical doses of amorphization were monitored in situ with transmission electron microscopy. The doses required for amorphization are compared with the structures, bond-types, compositions, and physical properties of the silicates using simple correlation methods and more complex multivariate statistical analysis. These analyses were made in order to determine which properties most affect the critical amorphization dose. Simple two-variable correlations indicate that melting point, efficiency of atomic packing, the dimensionality of SiO4 polymerization (DOSP), and bond ionicity have a relationship with critical amorphization dose. However, these relationships are evident only in selected portions of the data set; that is, for silicate phases with a common structure type. A clearer relationship between the silicate properties and critical amorphization dose was determined for the entire data set with multiple linear regression. Several regression models are proposed which describe the variation in amorphization dose. All regression models contain the following properties: (i) melting point; (ii) a structural variable (DOSP, elastic modulus, and/or atomic packing); and (iii) the proportion of Si-O bonding (instead of bond ionicity). The regression models are equivalent, because they represent combinations of similar properties. Notably, density and atomic mass are not controlling properties for the critical amorphization dose. Melting and amorphization by ion irradiation are apparently related processes. Neither melting point nor critical amorphization dose can be predicted by considering only the structure, composition, or bonding of a particular phase. The Si-O bond is the most covalent bond in silicates, and is the "weak link" in the structure with respect to amorphization. Thus, DOSP is also an important property, as the topology of these "weak links" influences a structure's ability to accumulate amorphous regions. The efficiency of atomic packing is related to the process of defect self-recombination during amorphization. The bulk modulus and shear modulus are important variables within the regression models because of their direct relationship to atomic packing. C1 UNIV NEW MEXICO,DEPT GEOL,ALBUQUERQUE,NM 87131. ARGONNE NATL LAB,ARGONNE,IL 60439. NR 62 TC 68 Z9 68 U1 0 U2 12 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 NOV PY 1992 VL 7 IS 11 BP 3080 EP 3102 DI 10.1557/JMR.1992.3080 PG 23 WC Materials Science, Multidisciplinary SC Materials Science GA JX922 UT WOS:A1992JX92200022 ER PT J AU SKLAD, PS MCHARGUE, CJ WHITE, CW FARLOW, GC AF SKLAD, PS MCHARGUE, CJ WHITE, CW FARLOW, GC TI ANALYTICAL ELECTRON-MICROSCOPY OF AL2O3 IMPLANTED WITH IRON IONS SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID RADIATION-DAMAGE; IRRADIATION DAMAGE; TEMPERATURE; CERAMICS; SAPPHIRE; HVEM AB Single crystals of alpha-Al2O3 were implanted with iron ions at room temperature to fluences ranging from 4 x 10(16) Fe cm-2 to 1 x 10(17) Fe cm-2 . The microstructure and composition in the implanted region were examined using analytical electron microscopy techniques. Special emphasis was placed on monitoring the microstructural changes which take place during post-implantation annealing. Clusters of metallic alpha-Fe were identified in the specimen after implantation to a dose of 1 x 10(17) Fe cm-2. Analytical electron microscopy of implanted specimens annealed in oxygen revealed the redistribution of the implanted iron and the formation of surface precipitates of alpha-Fe2O3, Subsurface precipitates of various forms of spinel, and, in some cases, subsurface precipitates of iron, depending on the annealing temperature. Examination of implanted specimens annealed under reducing conditions revealed the presence of precipitates of alpha-Fe. C1 WRIGHT STATE UNIV,DAYTON,OH 45435. RP SKLAD, PS (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 33 TC 10 Z9 10 U1 0 U2 4 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 NOV 1 PY 1992 VL 27 IS 21 BP 5895 EP 5904 DI 10.1007/BF01119757 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA JW119 UT WOS:A1992JW11900035 ER PT J AU USMAR, SG WRIGHT, RN AF USMAR, SG WRIGHT, RN TI SUBMICROSTRUCTURAL AND MICROSTRUCTURAL EVOLUTION OF PURE AND OXYGEN CONTAMINATED VACUUM MELT-SPUN 99.9999-PERCENT AL AND AL90 AT PPM C SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID POSITRON; ALUMINUM; LIFETIME; SYSTEM AB Positron lifetime (PLS) and TEM studies have been completed on a series of pure, carbon-doped (approximately 90 at p.p.m.) and oxygen contaminated (340-670 at p.p.m.) vacuum melt-spun (VacMS) aluminium samples. Both TEM and PLS data have shown pure and carbon-doped samples to be fully annealed at approximately 473 K. Oxygen-contaminated samples were found to contain defects including dislocations (TEM) and small vacancy clusters (PLS) up to the highest annealing temperatures (853 K) studied. The results show that the presence of oxygen completely dominates the evolution of both microstructure and submicrostructure in VacMS aluminium. C1 ASSOCIATED UNIV INC,BROOKHAVEN NATL LAB,LONG ISL,NY 11973. EG&G IDAHO INC,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415. RP USMAR, SG (reprint author), UNIV BRISTOL,HH WILLS PHYS LAB,TYNDALL AVE,BRISTOL BS8 1TL,AVON,ENGLAND. NR 20 TC 0 Z9 0 U1 0 U2 0 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD NOV 1 PY 1992 VL 27 IS 21 BP 5916 EP 5920 DI 10.1007/BF01119760 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA JW119 UT WOS:A1992JW11900038 ER PT J AU GALLAGHER, DE HOYT, EW KIRBY, RE AF GALLAGHER, DE HOYT, EW KIRBY, RE TI SURFACE SEGREGATION OF BORON IN DISPERSION-STRENGTHENED COPPER SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB The improved yield strength of annealed dispersion-strengthened copper (DSC) over conventional oxygen-free high-conductivity copper makes it a possible candidate for use in extremely high potential gradient particle accelerator structures where stability is of critical importance. Test brazes of such structures show that the surface of DSC is not readily wetted by conventional gold-based braze alloys used for copper. Surface analyses (by X-ray photoelectron spectroscopy and Auger electron spectroscopy) of samples raised to brazing temperature show the presence of boron, which diffuses to the surface and possibly interferes with the wetting process. Boron is an intentional oxygen scavenger added to the DSC during manufacture. Alumina, the primary additive in the strengthening process, is not detected on the surface. RP GALLAGHER, DE (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 6 TC 3 Z9 3 U1 1 U2 2 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD NOV 1 PY 1992 VL 27 IS 21 BP 5926 EP 5930 DI 10.1007/BF01119762 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA JW119 UT WOS:A1992JW11900040 ER PT J AU SUCK, JB EGELSTAFF, PA ROBINSON, RA SIVIA, DS TAYLOR, AD AF SUCK, JB EGELSTAFF, PA ROBINSON, RA SIVIA, DS TAYLOR, AD TI NEUTRON BRILLOUIN-SCATTERING IN A METALLIC-GLASS SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID DISPERSION AB The dispersion of collective modes in a metallic glass (Mg70Zn30) measured previously at the thermal neutron time-of-flight spectrometer, IN4, of the HFR of the ILL has been extended towards lower momentum transfers, down to the first pseudo-Brillouin zone, for the first time. This extension to momentum transfers not accessible up to now was possible using the high-resolution time-of-flight spectrometer, HET, at the new spallation source, ISIS. In the region of overlap, the two parts of the dispersion determined with different samples of the same metallic glass on different instruments agree very well. Also, the earlier discrepancies with the dispersion determined for this metallic glass from a computer simulation have been almost completely eliminated due to a more recent and more complete investigation. C1 KERNFORSCHUNGSZENTRUM KARLSRUHE GMBH, INST NUKL FESTKORPERPHYS, W-7500 KARLSRUHE 1, GERMANY. UNIV GUELPH, DEPT PHYS, GUELPH N1G 2W1, ONTARIO, CANADA. LOS ALAMOS NATL LAB, LES ALAMOS NEUTRON SCATTERING CTR, LOS ALAMOS, NM 87545 USA. RUTHERFORD APPLETON LAB, ISIS FACIL, DIDCOT OX11 0QX, OXON, ENGLAND. RP SUCK, JB (reprint author), INST MAX VON LAUE PAUL LANGEVIN, BP 156, F-38042 GRENOBLE, FRANCE. NR 6 TC 12 Z9 12 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 EI 1873-4812 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 1992 VL 150 IS 1-3 BP 245 EP 250 DI 10.1016/0022-3093(92)90130-C PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA KD157 UT WOS:A1992KD15700048 ER PT J AU SABOUNGI, ML PRICE, DL AF SABOUNGI, ML PRICE, DL TI A NOVEL PHASE-TRANSITION IN ALLOYS SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5TH INTERNATIONAL CONF ON THE STRUCTURE OF NON-CRYSTALLINE MATERIALS ( NCM 5 ) CY SEP 02-06, 1991 CL SENDAI, JAPAN SP TOHOHU UNIV, INST MAT RES, JAPANESE MINIST EDUC SCI & CULTURE, JAPANESE SOC PROMOT SCI, MIYAGI PREFECTURE, SENDAI CITY, NISHINA MEM FDN, MURATA SCI FDN, NIPPON SHEET GLASS FDN MAT SCI, ASASHI GLASS FDN ID METAL LEAD ALLOYS; HEAT-CAPACITY; ALKALI LEAD; LIQUID; CSPB; KPB AB The intermediate phase of the intermetallic alloy CsPb is shown to be a plastic crystal characterized by jump reorientations of Cs4Pb4 structural units. The wavevector variation of the elastic and quasielastic neutron scattering intensities is well reproduced by a simple model of independent structural units jumping between the four orientations observed in the crystal at room temperature. This represents the first observation of a plastic crystal phase in a metal alloy. RP SABOUNGI, ML (reprint author), ARGONNE NATL LAB,DIV MAT SCI,9700 S CASS AVE,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 22 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 1992 VL 150 IS 1-3 BP 260 EP 265 DI 10.1016/0022-3093(92)90133-5 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA KD157 UT WOS:A1992KD15700051 ER PT J AU PRICE, DL SABOUNGI, ML SUSMAN, S VOLIN, KJ WRIGHT, AC AF PRICE, DL SABOUNGI, ML SUSMAN, S VOLIN, KJ WRIGHT, AC TI DYNAMICS OF VITREOUS AND MOLTEN ZINC-CHLORIDE SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5TH INTERNATIONAL CONF ON THE STRUCTURE OF NON-CRYSTALLINE MATERIALS ( NCM 5 ) CY SEP 02-06, 1991 CL SENDAI, JAPAN SP TOHOHU UNIV, INST MAT RES, JAPANESE MINIST EDUC SCI & CULTURE, JAPANESE SOC PROMOT SCI, MIYAGI PREFECTURE, SENDAI CITY, NISHINA MEM FDN, MURATA SCI FDN, NIPPON SHEET GLASS FDN MAT SCI, ASASHI GLASS FDN ID DIFFRACTION ISOSBESTIC POINTS; SIXSE1-X GLASS SYSTEM; CHALCOGENIDE GLASSES; VIBRATIONAL-SPECTRA; NETWORK DYNAMICS; NEUTRON; SILICA; SCATTERING; DISELENIDE; LIQUID AB The dynamics of vitreous and molten zinc chloride have been studied with inelastic neutron scattering at the Intense Pulsed Neutron Source. The results are analyzed in terms of the scattering function, S(Q, E) and the effective vibrational density of states, G(E). The vibrational spectra of both glass and liquid are dominated by broad features centered at 15 and 35 meV which are identified with F2 modes of ZnCl42- tetrahedra. The other two normal modes are not observed because of inadequate resolution and broadening and overlap resulting from coupling between tetrahedra. The behavior of ZnCl2 is contrasted with other tetrahedrally coordinated glasses that have been studied with the same technique. RP PRICE, DL (reprint author), ARGONNE NATL LAB,DIV MAT SCI,BLDG 223,9700 S CASS AVE,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 20 TC 8 Z9 8 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 1992 VL 150 IS 1-3 BP 287 EP 291 DI 10.1016/0022-3093(92)90138-A PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA KD157 UT WOS:A1992KD15700056 ER PT J AU WILLIT, JL MILLER, WE BATTLES, JE AF WILLIT, JL MILLER, WE BATTLES, JE TI ELECTROREFINING OF URANIUM AND PLUTONIUM - A LITERATURE-REVIEW SO JOURNAL OF NUCLEAR MATERIALS LA English DT Review ID TEMPERATURE-DEPENDENCE; LIQUID AB This report is a comprehensive review of the literature on uranium and plutonium electrorefining in molten salts. It covers work published from 1943 to November 1991. Electrodeposition and electrodissolution at solid and liquid metal electrodes are discussed as well as mass transfer in liquid metal and molten salt phases. RP WILLIT, JL (reprint author), ARGONNE NATL LAB,DIV CHEM TECHNOL,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 136 TC 71 Z9 72 U1 3 U2 23 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD NOV PY 1992 VL 195 IS 3 BP 229 EP 249 DI 10.1016/0022-3115(92)90515-M PG 21 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA KB693 UT WOS:A1992KB69300001 ER PT J AU OLSEN, CE COMSTOCK, AL SANDENAW, TA AF OLSEN, CE COMSTOCK, AL SANDENAW, TA TI MAGNETIC-SUSCEPTIBILITY OF PURE PLUTONIUM METAL ABOVE 300-K SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article AB The magnetic susceptibility of two samples of plutonium, one highly oriented and the other randomly oriented, were measured on heating between 300 and 850 K. The susceptibilities of the alpha, beta, gamma, delta, delta-prime, and epsilon phases were determined as a function of temperature. Principal magnetic axes and the magnetic anisotropy with respect to these axes were determined for the alpha, beta, gamma, and the delta phases. RP OLSEN, CE (reprint author), LOS ALAMOS NATL LAB,NMT-5,MS E506,LOS ALAMOS,NM 87545, USA. NR 16 TC 11 Z9 11 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD NOV PY 1992 VL 195 IS 3 BP 312 EP 316 DI 10.1016/0022-3115(92)90522-M PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA KB693 UT WOS:A1992KB69300008 ER PT J AU LARSON, SM PENTLOW, KS VOLKOW, ND WOLF, AP FINN, RD LAMBRECHT, RM GRAHAM, MC DIRESTA, G BENDRIEM, B DAGHIGHIAN, F YEH, SDJ WANG, GJ CHEUNG, NKV AF LARSON, SM PENTLOW, KS VOLKOW, ND WOLF, AP FINN, RD LAMBRECHT, RM GRAHAM, MC DIRESTA, G BENDRIEM, B DAGHIGHIAN, F YEH, SDJ WANG, GJ CHEUNG, NKV TI PET SCANNING OF IODINE-124-3F8 AS AN APPROACH TO TUMOR DOSIMETRY DURING TREATMENT PLANNING FOR RADIOIMMUNOTHERAPY IN A CHILD WITH NEUROBLASTOMA SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article ID POSITRON EMISSION TOMOGRAPHY; HUMAN NEURO-BLASTOMA; MONOCLONAL-ANTIBODIES; I-124 AB A patient with advanced neuroblastoma who had failed chemotherapy presented with a large abdominal mass and virtually total bone marrow replacement by tumor on repeated marrow biopsies. She was considered a candidate for a Phase I I-131-3F8 radioimmunotherapy trial, (MSKCC 89-141A). As a potential aid to treatment planning, a test dose of I-124-3F8 was injected and the patient was imaged over the 72 hr postinjection using two BGO based PET scanners of different designs. Time activity curves were obtained, and the cumulated activity concentration of radiolabeled 3F8 in tumor was determined. Based on MIRD, an estimated radiation absorbed dose for 13, 1-3F8 was 7.55 rad/mCi, in the most antibody avid lesions. Because of low uptake and unfavorable dosimetry in some bulky tumor sites, it was decided not to treat the patient with radiolabeled antibody. Positron emission tomography of I-124-labeled antibodies can be used to measure cumulated activity or residence time in tumor for more accurate estimates of radiation absorbed tumor dose from radioiodinated antibodies and can help guide management decisions in patients who are candidates for radioimmunotherapy. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. KING FAISAL SPECIALIST HOSP & RES CTR,RIYADH 11211,SAUDI ARABIA. RP LARSON, SM (reprint author), MEM SLOAN KETTERING CANC CTR,1275 YORK AVE,NEW YORK,NY 10021, USA. NR 19 TC 93 Z9 93 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD NOV PY 1992 VL 33 IS 11 BP 2020 EP 2023 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA JW929 UT WOS:A1992JW92900026 PM 1432165 ER PT J AU ZHOU, O COX, DE AF ZHOU, O COX, DE TI STRUCTURES OF C-60 INTERCALATION COMPOUNDS SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article DE FULLERENE INTERCALATION COMPOUNDS; X-RAY POWDER DIFFRACTION; STRUCTURE REFINEMENT ID SOLID C60; PRESSURE-DEPENDENCE; POWDER DIFFRACTION; MOLECULAR-DYNAMICS; CRYSTAL-STRUCTURES; DOPED C60; SUPERCONDUCTIVITY; SPECTROSCOPY; TRANSITION; BUCKMINSTERFULLERENE AB In the past two years, many intercalation compounds of C60 have been prepared and characterized by X-ray powder diffraction techniques. The M-C60 systems with M = Li, Na, K, Rb, Cs and Ca have been studied, and the structures of several compounds have been determined in considerable detail, including the face-centered cubic superconductors K3C60 and Rb3C60, body-centered tetragonal K4C60, body-centered cubic M6C60 with M = K, Rb and Cs, simple hexagonal C60I4, and the monoclinic molecular ferromagnet tetrakis-dimethylamino-ethylene (TDAE) C2N4(CH3)8C60. The Rietveld profile technique for structure refinement coupled with high resolution synchrotron X-ray powder data has played an important role in providing accurate structural data for many of these compounds. In this article, a detailed review of the literature dealing with structural studies on the intercalated compounds of C60 will be given. C1 UNIV PENN,RES STRUCT MATTER LAB,PHILADELPHIA,PA 19104. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP ZHOU, O (reprint author), UNIV PENN,DEPT MAT SCI & ENGN,PHILADELPHIA,PA 19104, USA. NR 71 TC 139 Z9 139 U1 3 U2 20 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD NOV PY 1992 VL 53 IS 11 BP 1373 EP 1390 DI 10.1016/0022-3697(92)90233-4 PG 18 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA JV018 UT WOS:A1992JV01800005 ER PT J AU WUDL, F THOMPSON, JD AF WUDL, F THOMPSON, JD TI BUCKMINSTERFULLERENE C-60 AND ORGANIC FERROMAGNETISM SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article DE ORGANIC FERROMAGNETISM; BUCKMINSTERFULLERENE C-60; ORGANIC CHARGE TRANSFER SOLID; SOFT FERROMAGNET; ITINERANT FERROMAGNET ID CHARGE-TRANSFER COMPLEXES; SOLVATED BUCKIDE ION; C60 BUCKMINSTERFULLERENE; EFFICIENT PRODUCTION; C70 CLUSTERS; FULLERENES; SUPERCONDUCTIVITY; FERRIMAGNET; MODEL AB Interest in the electronic properties of C60 led to the discovery of metals, superconductors and a solid with a transition to a magnetic state. The approaches to organic ferromagnets are reviewed briefly, with emphasis on the McConnell model. The review is followed by the description of the magnetic properties of C60 TDAE at ambient pressure and under hydrostatic pressure, showing that the 16 K transition is extremely pressure sensitive and that the effect of pressure is reversible. An explanation of the properties of C60 TDAE in terms of a modification of the McConnell model is described for the first time. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. UNIV CALIF SANTA BARBARA,DEPT PHYS,SANTA BARBARA,CA 93106. UNIV CALIF SANTA BARBARA,DEPT CHEM,SANTA BARBARA,CA 93106. RP WUDL, F (reprint author), UNIV CALIF SANTA BARBARA,INST POLYMERS & ORGAN SOLIDS,SANTA BARBARA,CA 93106, USA. NR 55 TC 46 Z9 46 U1 2 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD NOV PY 1992 VL 53 IS 11 BP 1449 EP 1455 DI 10.1016/0022-3697(92)90238-9 PG 7 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA JV018 UT WOS:A1992JV01800010 ER PT J AU FISCHER, JE COX, DE AF FISCHER, JE COX, DE TI PHYSICS AND CHEMISTRY OF FULLERENE-BASED SOLIDS - PREFACE SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Editorial Material C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RP FISCHER, JE (reprint author), UNIV PENN,RES STRUCT MATTER LAB,PHILADELPHIA,PA 19104, USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD NOV PY 1992 VL 53 IS 11 BP R5 EP R5 DI 10.1016/0022-3697(92)90229-7 PG 1 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA JV018 UT WOS:A1992JV01800001 ER PT J AU BANDYOPADHYAY, D GORENSTEIN, M STOCKER, H GREINER, W SORGE, H AF BANDYOPADHYAY, D GORENSTEIN, M STOCKER, H GREINER, W SORGE, H TI PION CHEMICAL EQUILIBRATION IN HEAVY-ION COLLISIONS - RELATIVISTIC QUANTUM MOLECULAR DYNAMIC ANALYSIS SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Letter AB In the framework of relativistic quantum molecular dynamics we find that the pion system produced in central heavy-ion collisions at E(lab)/A is similar to 1 GeV/nucl is out of chemical equilibrium. Pion chemical potential is large and decreases during the expansion stage. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. INST THEORET PHYS,KIEV 252130,UKRAINE,USSR. RP BANDYOPADHYAY, D (reprint author), JW GOETHE UNIV,INST THEORET PHYS,POSTFACH 111932,W-6000 FRANKFURT 11,GERMANY. RI Stoecker, Horst/D-6173-2013 OI Stoecker, Horst/0000-0002-3282-3664 NR 13 TC 2 Z9 2 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD NOV PY 1992 VL 18 IS 11 BP L187 EP L190 DI 10.1088/0954-3899/18/11/001 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA JW748 UT WOS:A1992JW74800001 ER PT J AU PECK, SC REINHARDT, D OLSON, DC BOLLER, T KENDE, H AF PECK, SC REINHARDT, D OLSON, DC BOLLER, T KENDE, H TI LOCALIZATION OF THE ETHYLENE-FORMING ENZYME FROM TOMATOES, 1-AMINOCYCLOPROPANE-1-CARBOXYLATE OXIDASE, IN TRANSGENIC YEAST SO JOURNAL OF PLANT PHYSIOLOGY LA English DT Article DE 1-AMINOCYCLOPROPANE-1-CARBOXYLATE OXIDASE; ETHYLENE-FORMING ENZYME; TOMATO; TRANSGENIC YEAST; VACUOLE ID MESSENGER-RNA; ISOLATED VACUOLES; BINDING PROTEINS; EXPRESSION; ACID; IDENTIFICATION; BIOSYNTHESIS; INHIBITION; CONVERSION; SEQUENCE AB The localization of the ethylene-forming enzyme, 1-aminocyclopropane-1-carboxylate (ACC) oxidase, was studied in yeast that had been transformed to express ACC oxidase from tomato fruits when induced with galactose. Since at least part of the ethylene-forming activity in plants was found in association with vacuoles, we were particularly interested to find out whether ACC oxidase would be targeted to the yeast vacuole. Transgenic ACC oxidase began to accumulate ca. 2 h after transfer of yeast cells to medium containing galactose. This was determined by measuring ACC oxidase activity and by immunoblot analysis using ACC oxidase-specific antibodies. Protoplasts prepared from transgenic yeast retained 84 % of the ACC oxidase activity of intact cells. Vacuoles isolated from such protoplasts did not possess ACC oxidase activity. Immunoblot analysis confirmed that intact cells and protoplasts contained approximately equal levels of ACC oxidase protein whereas vacuoles did not contain any detectable amounts of the protein. Differential centrifugation indicated that ACC oxidase from transgenic yeast was associated with the particulate fraction of the homogenate. It is not known whether this represents specific binding of the enzyme to a particulate component of the cell or nonspecific attachment that may have occurred during homogenization. C1 UNIV BASEL, PFLANZENPHYSIOL ABT, CH-4056 BASEL, SWITZERLAND. RP PECK, SC (reprint author), MICHIGAN STATE UNIV, DOE, PLANT RES LAB, E LANSING, MI 48824 USA. RI Boller, Thomas/G-3500-2012; Reinhardt, Didier/M-8508-2014 OI Reinhardt, Didier/0000-0003-3495-6783 NR 28 TC 19 Z9 20 U1 0 U2 1 PU ELSEVIER GMBH, URBAN & FISCHER VERLAG PI JENA PA OFFICE JENA, P O BOX 100537, 07705 JENA, GERMANY SN 0176-1617 EI 1618-1328 J9 J PLANT PHYSIOL JI J. Plant Physiol. PD NOV PY 1992 VL 140 IS 6 BP 681 EP 686 PG 6 WC Plant Sciences SC Plant Sciences GA KA806 UT WOS:A1992KA80600007 ER PT J AU BUSH, SH AF BUSH, SH TI FAILURE MECHANISMS IN NUCLEAR-POWER-PLANT PIPING SYSTEMS SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article RP BUSH, SH (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 19 TC 17 Z9 19 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD NOV PY 1992 VL 114 IS 4 BP 389 EP 395 DI 10.1115/1.2929244 PG 7 WC Engineering, Mechanical SC Engineering GA KA839 UT WOS:A1992KA83900001 ER PT J AU CHEVERTON, RD SELBY, DL AF CHEVERTON, RD SELBY, DL TI A PROBABILISTIC APPROACH TO THE EVALUATION OF THE PTS ISSUE SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID THERMAL-SHOCK AB An integrated probabilistic approach for the evaluation of the pressurized-thermal-shock (PTS) issue was developed at the Oak Ridge National Laboratory (ORNL) at the request of the Nuclear Regulatory Commission (NRC). The purpose was to provide a method for identifying dominant plant design and operating features, evaluating possible remedial measures and the validity of the NRC PTS screening criteria, and to provide an additional tool for estimating vessel life expectancy. The approach was to be integrated in the sense that it would include the postulation of transients; estimates of their frequencies of occurrence; systems analyses to obtain the corresponding primary-system pressure, downcomer coolant temperature, and fluid-film heat-transfer coefficient adjacent to the vessel wall; and a probabilistic fracture-mechanics analysis using the latter data as input. A summation of the products of frequency of transient and conditional probability of failure for all postulated transients provides an estimate of frequency of vessel failure. In the process of developing the integrated-pressurized-thermal-shock (IPTS) methodology, three specific-plant analyses were conducted. The results indicate that the NRC screening criteria may not be appropriate for all U.S. pressurized-water-reactor (PWR) plants; that is, for some PWRs, the calculated mean frequency of vessel failure corresponding to the screening criteria may be greater than the "primary-acceptance-criterion" value in Regulatory Guide 1.154. A recent review of the ORNL IPTS study, which was completed in 1985, indicates that there are a number of areas in which the methodology can and should be updated, but it is not clear whether the update will increase or decrease the calculated probabilities. RP CHEVERTON, RD (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 32 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 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD NOV PY 1992 VL 114 IS 4 BP 396 EP 404 DI 10.1115/1.2929245 PG 9 WC Engineering, Mechanical SC Engineering GA KA839 UT WOS:A1992KA83900002 ER PT J AU KIM, WN DENN, MM AF KIM, WN DENN, MM TI PROPERTIES OF BLENDS OF A THERMOTROPIC LIQUID-CRYSTALLINE POLYMER WITH A FLEXIBLE POLYMER (VECTRA PET) SO JOURNAL OF RHEOLOGY LA English DT Article ID POLYDIMETHYLSILOXANE-POLYOXYETHYLENE BLENDS; EMULSION MODEL; VISCOELASTIC PROPERTIES; MORPHOLOGY; COPOLYMER; RHEOLOGY; SHEAR; MELT; POLY(ETHYLENE-TEREPHTHALATE); THERMODYNAMICS AB Blends of Vectra A900, a thermotropic liquid crystalline polymer (LCP), and poly(ethylene terephthalate) (PET) were studied over the entire composition range using scanning electron microscopy, differential scanning calorimetry, and rotational rheometry. There is some interaction between the polymers, as evidenced by melting- and crystallization-point depression in the PET phase. The shear rheology deviates substantially from simple mixing laws and from predictions of an emulsion model of dispersed blends. The viscosity of LCP-rich compositions exceeds that of either component at low rates and frequencies. The viscosity of PET-rich compositions falls below that of either component at low rates and frequencies. The latter observation cannot be explained by deformation and orientation of the LCP phase, since the dispersed LCP inclusions remain spherical following steady shear. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. NR 37 TC 73 Z9 73 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0148-6055 J9 J RHEOL JI J. Rheol. PD NOV PY 1992 VL 36 IS 8 BP 1477 EP 1498 DI 10.1122/1.550269 PG 22 WC Mechanics SC Mechanics GA JY213 UT WOS:A1992JY21300002 ER PT J AU BROWN, DR LAMARCHE, JL SPANNER, GE AF BROWN, DR LAMARCHE, JL SPANNER, GE TI CHEMICAL ENERGY-STORAGE SYSTEM FOR SOLAR ELECTRIC GENERATING-SYSTEM (SEGS) SOLAR THERMAL POWER-PLANT SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB The Pacific North west Laboratory evaluated the potential feasibility of using chemical energy storage at the Solar Electric Generating System (SEGS) power plants developed by Luz International. Like sensible or latent heat energy storage systems, chemical energy storage can be beneficially applied to solar thermal power plants to dampen the impact of cloud transients, extend the daily operating period, and/or allow a higher fraction of power production to occur during high-valued peak demand periods. Higher energy storage densities make chemical energy storage a potentially attractive option. The results of the evaluation indicated that a system based on the reversible reaction, CaO + H2O = Ca(OH)2, could be technically and economically feasible for this application, but many technical and economic issues must be resolved. RP BROWN, DR (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 3 TC 8 Z9 8 U1 0 U2 8 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 1992 VL 114 IS 4 BP 212 EP 218 DI 10.1115/1.2930008 PG 7 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA JY937 UT WOS:A1992JY93700002 ER PT J AU PESARAN, AA AF PESARAN, AA TI EXPERIMENTS ON OXYGEN DESORPTION FROM SURFACE WARM SEAWATER UNDER OPEN-CYCLE OCEAN THERMAL-ENERGY CONVERSION SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB This paper presents the results of scoping deaeration experiments conducted with warm surface seawater under open-cycle ocean thermal energy conversion (OC-OTEC) conditions. Concentrations of dissolved oxygen in seawater at three locations (in the supply water, water leaving the predeaerator, and discharge water from an evaporator) were measured and used to estimate oxygen desorption levels. The results suggest that 7 percent to 60 percent of the dissolved oxygen in the supply water was desorbed from seawater in the predeaerator for pressures ranging from 35 to 9 kPa. Bubble injection in the upcomer increased the oxygen desorption rate by 20 percent to 60 percent. The data also indicated that at typical OC-OTEC evaporator pressures, when flash evaporation in the evaporator occurred, 75 percent to 95 percent of the dissolved oxygen was desorbed overall from the warm seawater. The results were used to find the impact of a single-stage predeaeration scheme on the power to remove noncondensable gases in an OC-OTEC plant. RP PESARAN, AA (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 1992 VL 114 IS 4 BP 246 EP 253 DI 10.1115/1.2930013 PG 8 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA JY937 UT WOS:A1992JY93700007 ER PT J AU DIRKS, JA WILLIAMS, TA BROWN, DR AF DIRKS, JA WILLIAMS, TA BROWN, DR TI PERFORMANCE AND COST IMPLICATIONS OF THE FIXED MIRROR, DISTRIBUTED FOCUS (FMDF) COLLECTOR SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB The Fixed Mirror, Distributed Focus (FMDF) hemispherical bowl is a solar thermal power technology which has been studied for several years as a potentially attractive means of producing electricity. This paper discusses projections of the collector (concentrator and receiver) performance and cost that could be achieved by five variations of the FMDF technology, based on the assumption of continued technology development and high volume production. The major loss mechanisms were determined for the concentrators and receivers and then design point losses and efficiencies were developed. The Pacific Northwest Laboratory (PNL) computer code SOLSTEP was then used to determine the annual performance. The cost analysis was based on a "commercial" solar thermal industry that could exist by the late 1990s. The industry is assumed to be installing several hundred megawatts per year of electric capacity, and is assumed to have improved the maturity of solar thermal components so that technical and economic risks are similar to other energy systems. RP DIRKS, JA (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 1992 VL 114 IS 4 BP 254 EP 259 DI 10.1115/1.2930014 PG 6 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA JY937 UT WOS:A1992JY93700008 ER PT J AU COOLING, BF AF COOLING, BF TI STRUGGLE FOR THE SHENANDOAH - ESSAYS ON THE 1864 VALLEY CAMPAIGN - GALLAGHER,GW SO JOURNAL OF SOUTHERN HISTORY LA English DT Book Review RP COOLING, BF (reprint author), US DOE,WASHINGTON,DC, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SOUTHERN HISTORICAL ASSN PI ATHENS PA UNIV GEORGIA HISTORY DEPT, ATHENS, GA 30602 SN 0022-4642 J9 J SOUTHERN HIST JI J. South. Hist. PD NOV PY 1992 VL 58 IS 4 BP 730 EP 731 DI 10.2307/2210823 PG 2 WC History SC History GA KA956 UT WOS:A1992KA95600038 ER PT J AU ASEM, EK SIMPSON, DJ MARRONE, BL AF ASEM, EK SIMPSON, DJ MARRONE, BL TI HORMONE STIMULATED STEROID-BIOSYNTHESIS IN GRANULOSA-CELLS STUDIED WITH A FLUOROGENIC PROBE FOR CYTOCHROME P-450SCC SO JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY LA English DT Article ID SIDE-CHAIN CLEAVAGE; MESSENGER-RIBONUCLEIC-ACID; FOWL GALLUS-DOMESTICUS; LEYDIG TUMOR-CELLS; LUTEINIZING-HORMONE; PROGESTERONE PRODUCTION; FOLLICULAR MATURATION; PROTEIN-KINASE; CHOLESTEROL-METABOLISM; OVARIAN FOLLICLES AB The regulation of steroidogenesis by luteinizing hormone (LH) was studied in granulosa cells during follicular development using a fluorescent reporter assay based on the metabolism of a fluorescent probe specific for cytochrome P-450scc (cholesterol side-chain cleavage enzyme). Intact granulosa cells or mitochondria were obtained from the first (F1) second (F2) and third (F3) largest preovulatory follicles of the hen ovary and incubated with the fluorogenic substrate. Metabolism of this substrate by cytochrome P-450scc generates the highly fluorescent resorufin anion (the fluorescent reporter). In both mitochondria and intact granulosa cells, incubated with the fluorescent substrate, an increase in resorufin fluorescence was observed and the increase was greater in samples derived from F1 than in samples from F2 or F3. In cells, LH added simultaneously with the P450scc substrate significantly increased resorufin fluorescence above control values in a time- and dose-dependent manner up to 2-3 h after the incubation was initiated. Forskolin and 8-bromo-cAMP also stimulated metabolism of the P-450scc substrate significantly by 15 min. When granulosa cells were preincubated with LH before exposure to the P-450scc substrate resorufin fluorescence was significantly attenuated compared to controls (not exposed to LH in the preincubation period). The decrease in resorufin fluorescence observed when cells were pretreated with LH, may be due to the release of cholesterol from endogenous pools and its competition with the exogenous fluorogenic for the substrate P-450scc enzyme. In granulosa cells that were preloaded with the P-450scc substrate, the stimulatory effect of LH treatment remained constant from 30 min to 2 h after hormone addition. The results show that this fluorescent probe can be used in a rapid assay for the continuous measurement of the acute effects of hormone agonists on cholesterol conversion to pregnenolone in steroidogenic cells. C1 LOS ALAMOS NATL LAB,DIV LIFE SCI,LOS ALAMOS,NM 87545. RP ASEM, EK (reprint author), PURDUE UNIV,SCH VET MED,DEPT PHYSIOL & PHARMACOL,W LAFAYETTE,IN 47907, USA. FU NICHD NIH HHS [HD22195, HD27345] NR 43 TC 4 Z9 4 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0960-0760 J9 J STEROID BIOCHEM JI J. Steroid Biochem. Mol. Biol. PD NOV PY 1992 VL 43 IS 6 BP 479 EP 487 DI 10.1016/0960-0760(92)90234-A PG 9 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA JX499 UT WOS:A1992JX49900001 PM 1419883 ER PT J AU JOHNSON, PA HOPSON, TM SHANKLAND, TJ AF JOHNSON, PA HOPSON, TM SHANKLAND, TJ TI FREQUENCY-DOMAIN TRAVEL TIME (FDTT) MEASUREMENT OF ULTRASONIC-WAVES BY USE OF LINEAR AND NONLINEAR SOURCES SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID REFLECTOMETRY AB This paper describes a frequency-domain travel time (FDTT) method for measurement of direct and reflected travel times of sound waves based on the change in phase with frequency between a reference signal and a transmitted wave. An ordinary (linear) source can be used for measuring delays over shorter path lengths, and a parametric array (nonlinear) source can be used for measuring delays over longer path lengths. In the ordinary source measurement a reference signal is electronically multiplied with a signal that is time delayed by propagation through a sample. As frequency is incremented stepwise, the relative phase difference generates a corresponding stepwise dc output from the multiplier. For any travel path within the sample, there is a characteristic period of the dc signal whose reciprocal is proportional to the group time delay along the path. If more than one arrival exists, characteristic periods are superposed. An inverse Fourier transform of the frequency signal gives the discrete arrival times for each path. In the parametric measurement, a second electronic multiplier is used to create an electronic difference frequency signal for phase comparison with a wave at the difference frequency created by nonlinear elastic interaction in the material. The FDTT method should be applicable to ultrasonic investigation of material properties, nondestructive evaluation, seismology, sonar, and architectural acoustics. RP JOHNSON, PA (reprint author), LOS ALAMOS NATL LAB,DIV EARTH & ENVIRONM SCI,MAIL STOP D443,LOS ALAMOS,NM 87545, USA. NR 13 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 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1992 VL 92 IS 5 BP 2842 EP 2850 DI 10.1121/1.404404 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA JX919 UT WOS:A1992JX91900036 ER PT J AU DOSKEY, PV PORTER, JA SCHEFF, PA AF DOSKEY, PV PORTER, JA SCHEFF, PA TI SOURCE FINGERPRINTS FOR VOLATILE NONMETHANE HYDROCARBONS SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID EMISSIONS; ORGANICS; SAMPLES AB Non-methane hydrocarbon (NMHC) source profiles consisting of 35 hydrocarbon species were measured for vehicle and petroleum refinery emissions. Refueling emissions were found to be sensitive to the grade and volatility class of fuel and to be composed mainly of saturated hydrocarbons such as n-butane and 2-methylbutane. Unsaturated and aromatic hydrocarbons, which are released from the tailpipe of vehicles as products of combustion and unburned fuel, were more prevalent in roadway emissions comprising approximately 34 percent of the total NMHCs. Cold-start emissions were nearly indistinguishable from the roadway emission profile. The only significant differences were in toluene, ethylene and acetylene, which may be related to the efficiency of combustion when the vehicle is initially started. Saturated hydrocarbon distributions of the hot-soak profiles were found to be similar to refueling emissions. The only significant difference in the profiles was in the aromatic content, which may be related to the grade of the gasoline and the effectiveness of evaporative emission control devices. The temporal variation in refinery emissions was significant and may be related to variations in refinery activities such as the production and blending of feed stocks to produce different fuels. C1 DAMES & MOORE,PARK RIDGE,IL. UNIV ILLINOIS,SCH PUBL HLTH,CHICAGO,IL 60680. RP DOSKEY, PV (reprint author), ARGONNE NATL LAB,DIV ENVIRONM RES,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 21 TC 37 Z9 39 U1 0 U2 7 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA PO BOX 2861, PITTSBURGH, PA 15230 SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD NOV PY 1992 VL 42 IS 11 BP 1437 EP 1445 PG 9 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA JZ291 UT WOS:A1992JZ29100006 ER PT J AU KIM, DS HRMA, P AF KIM, DS HRMA, P TI FOAMING IN GLASS MELTS PRODUCED BY SODIUM-SULFATE DECOMPOSITION UNDER RAMP HEATING CONDITIONS SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID OXIDATION AB Ramp heating a glass batch with sulfate permits determination of the foaming temperature and maximum foam height as a function of sulfate addition. Experiments revealed that, in the soda-lime glass studied, foam was produced when the mass fraction of SO3 in the glass was higher than 0.0027. With increasing sulfate content, the foaming temperature decreased and the maximum foam height increased until the mass fraction of SO3 was 0.01. Further additions of sulfate had little effect on foaming temperature and decreased maximum foam height. The results are discussed in terms of sulfate solubility and nonequilibrium effects. RP KIM, DS (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 30 TC 13 Z9 13 U1 1 U2 3 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD NOV PY 1992 VL 75 IS 11 BP 2959 EP 2963 DI 10.1111/j.1151-2916.1992.tb04371.x PG 5 WC Materials Science, Ceramics SC Materials Science GA JX136 UT WOS:A1992JX13600008 ER PT J AU WADE, RK PETROVIC, JJ AF WADE, RK PETROVIC, JJ TI PROCESSING TEMPERATURE EFFECTS ON MOLYBDENUM DISILICIDE SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Note ID MOSI2 AB A series of MoSi2 compacts were fabricated at increasing hot-pressing temperatures to achieve different grain sizes. The materials were evaluated by Vickers indentation fracture to determine room-temperature fracture toughness, hardness, and fracture mode. From 1500-degrees to 1800-degrees-C, MoSi2 had a constant 67% transgranular fracture and linearly increasing grain size from 14 to 21 mum. Above 1800-degrees-C, the fracture percentage increased rapidly to 97% transgranular at 1920-degrees-C (32-mum grain size). Fracture toughness and hardness decreased slightly with increasing temperature. MoSi2 processed at 1600-degrees-C had the highest fracture toughness and hardness values of 3.6 MPa.m1/2 and 9.9 GPa, respectively. The effects of SiO2 formation from oxygen impurities in the MoSi2 starting powders and MoSi2-Mo5Si3 eutectic liquid formation were studied. C1 LOS ALAMOS NATL LAB,DIV MAT SCI & TECHNOL,CERAM SCI & TECHNOL GRP,LOS ALAMOS,NM 87545. RP WADE, RK (reprint author), UNIV ARIZONA,DEPT MAT SCI & ENGN,ARIZONA MAT LABS,TUCSON,AZ 85712, USA. NR 24 TC 31 Z9 31 U1 4 U2 4 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD NOV PY 1992 VL 75 IS 11 BP 3160 EP 3162 DI 10.1111/j.1151-2916.1992.tb04406.x PG 3 WC Materials Science, Ceramics SC Materials Science GA JX136 UT WOS:A1992JX13600043 ER PT J AU SACHLEBEN, RA BURNS, JH AF SACHLEBEN, RA BURNS, JH TI CONFORMATIONAL-CHANGES OF SUBSTITUTED 14-CROWN-4 ETHERS UPON COMPLEXATION SO JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; C-13 CPMAS NMR; LITHIUM THIOCYANATE; MOLECULAR-STRUCTURE; CRYSTAL-STRUCTURE; SOLVENT-EXTRACTION; PHOSPHINIC ACID; SOLID-STATE; DIBENZO-14-CROWN-4; SELECTIVITY AB The crystal structures of 6-methylene-2,2,3,3,9,9,10,10-octamethyl-14-crown-4 (1), 2,2,3,3,6,9,9,10,10-nonamethyl-14-crown-4 (2) and its LiSCN complex (2-LiSCN), 6-methyl-enedibenzo-14-crown-4 (3), 6-methyldibenzo-14-crown-4 (4), and dibenzo-14-crown-4 (5), have been determined by X-ray diffraction. These results, in addition to published literature data, are used to compare the conformational changes of flexible vs. rigid 14-crown-4 molecules when each is complexed with LiSCN. In dibenzo-14-crown-4 the oxygen atoms are suitably arranged prior to complexation to form the base of a square pyramidal complex upon complexation with LiSCN, while 2,2,3,3,6,9,9,10,10-nonamethyl-14-crown-4 and other flexible ligands must undergo significant rearrangement of the ring system in order to achieve this configuration. C1 OAK RIDGE NATL LAB,DIV CHEM,POB 2008,OAK RIDGE,TN 37831. NR 33 TC 18 Z9 18 U1 0 U2 3 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 0300-9580 J9 J CHEM SOC PERK T 2 JI J. Chem. Soc.-Perkin Trans. 2 PD NOV PY 1992 IS 11 BP 1971 EP 1977 DI 10.1039/p29920001971 PG 7 WC Chemistry, Organic; Chemistry, Physical SC Chemistry GA JY856 UT WOS:A1992JY85600019 ER PT J AU FARMER, JC WANG, FT LEWIS, PR SUMMERS, LJ AF FARMER, JC WANG, FT LEWIS, PR SUMMERS, LJ TI DESTRUCTION OF CHLORINATED ORGANICS BY COBALT(III)-MEDIATED ELECTROCHEMICAL OXIDATION SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article AB In the future, mediated electrochemical oxidation (MEO) may be used for the ambient temperature destruction of hazardous waste and for the conversion of mixed waste to low-level radioactive waste. We have studied the Co(III)-mediated electrochemical oxidation of ethylene glycol, 1,3-dichloro-2-propanol, 2-monochloro-1-propanol, and isopropanol in sulfuric acid. The electrochemical reactor had a rotating cylinder anode that was operated well below the limiting current for Co(III) generation. Rates of CO2 generation were measured and used to calculate both destruction and current efficiencies for the process. We found that electrode separators can be eliminated in MEO processes based upon Co(III) and sulfuric acid. Electrodes must be separated by ion exchange membranes in classical Ag(II)-based processes. RP FARMER, JC (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 9 TC 39 Z9 42 U1 0 U2 0 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD NOV PY 1992 VL 139 IS 11 BP 3025 EP 3029 DI 10.1149/1.2069027 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA JX172 UT WOS:A1992JX17200008 ER PT J AU FERREIRA, MGS SILVA, TME CATARINO, A PANKUCH, M MELENDRES, CA AF FERREIRA, MGS SILVA, TME CATARINO, A PANKUCH, M MELENDRES, CA TI ELECTROCHEMICAL AND LASER RAMAN-SPECTROSCOPY STUDIES OF STAINLESS-STEEL IN 0.15M NACL SOLUTION SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID INSITU FTIR SPECTROSCOPY; IRON ELECTRODES; PASSIVE FILMS; ALKALINE-SOLUTIONS; PRODUCTS; SPECTRA; MOLYBDENUM; SURFACE; AUGER AB Potentiodynamic polarization curves were measured for Type AISI 304 and 316 stainless steels in 0.15M NaCl solution at 4, 20, and 40-degrees-C. The pitting potentials decreased with increasing temperature. A positive effect on the inhibition of passivity breakdown was found in the presence of molybdenum. Surface enhanced Raman spectroscopy (SERS) was carried out on AISI 316 stainless steel to identify the species present on the electrode surface as a function of potential. Results indicate the corrosion films to be highly disordered and most likely to consist of a mixture of the oxides and hydroxides of the component elements of the stainless steel. The potential dependence of the spectra may reflect the behavior of iron, which is the most abundant component in the alloy and most probably in the film. C1 ARGONNE NATL LAB, DIV MAT SCI & CHEM TECHNOL, ARGONNE, IL 60439 USA. RP FERREIRA, MGS (reprint author), Univ Tecn Lisboa, INST SUPER TECN, DEPT CHEM ENGN, P-1096 LISBON, PORTUGAL. RI Ferreira, Mario/D-5869-2014; Moura e Silva, Teresa/F-8778-2014 OI Ferreira, Mario/0000-0002-2071-9851; Moura e Silva, Teresa/0000-0001-8402-6600 NR 32 TC 29 Z9 30 U1 2 U2 12 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD NOV PY 1992 VL 139 IS 11 BP 3146 EP 3151 DI 10.1149/1.2069047 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA JX172 UT WOS:A1992JX17200028 ER PT J AU FLEMING, JG ROHERTYOSMUN, E GODSHALL, NA AF FLEMING, JG ROHERTYOSMUN, E GODSHALL, NA TI LOW-TEMPERATURE, HIGH-STRENGTH, WAFER-TO-WAFER BONDING SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID SILICON-ON-INSULATOR AB High strength bonds can be formed between portions of silicon wafer coated with reflowed BPSG at temperatures as low as 160-degrees-C. Both a novel modified cantilever beam analysis, and crude physical methods attest to the strength of the bonds formed. Strong bonds between thermal oxides also have been observed, indicating that neither boron nor phosphorous are essential to the process. Preparation cleanliness may be the key to low temperature, high strength bonding. Recent work in the glass sol-gel area supports the hypothesis that this process is the result of a low temperature condensation reaction. RP FLEMING, JG (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 13 TC 6 Z9 6 U1 0 U2 3 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD NOV PY 1992 VL 139 IS 11 BP 3300 EP 3302 DI 10.1149/1.2069071 PG 3 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA JX172 UT WOS:A1992JX17200052 ER PT J AU PENETRANTE, BM BARDSLEY, JN WOOD, WM SIDERS, CW DOWNER, MC AF PENETRANTE, BM BARDSLEY, JN WOOD, WM SIDERS, CW DOWNER, MC TI IONIZATION-INDUCED FREQUENCY-SHIFTS IN INTENSE FEMTOSECOND LASER-PULSES SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID SELF-PHASE MODULATION; ENERGY-CONSERVATION; NOBLE-GASES; RADIATION; PLASMA; PICOSECOND; LIGHT AB Electromagnetic plasma computer simulations are used to analyze the frequency shifts caused by the ionization of atmospheric-density noble gases during interaction with intense femtosecond laser pulses; the results are presented and compared with experimental data. The simulations trace the temporal evolution of plasma growth during the femtosecond ionizing pulse and calculate the resulting self-induced blue shift of the ionizing pulse spectrum. Variations with pulse intensity, gas pressure, and gas species are calculated. The relative contributions of strong-field ionization and electron-impact ionization on the frequency shifts are discussed. The simulations provide qualitative explanations of most of the features observed experimentally in the blue-shifted spectra. The technique of spectral blue shifting intense femtosecond laser pulses provides a new diagnostic tool for studying strong-field ionization and laser-induced breakdown in dense plasmas. C1 UNIV TEXAS,DEPT PHYS,AUSTIN,TX 78712. RP PENETRANTE, BM (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV HIGH TEMP PHYS,LIVERMORE,CA 94550, USA. NR 24 TC 49 Z9 49 U1 1 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD NOV PY 1992 VL 9 IS 11 BP 2032 EP 2040 DI 10.1364/JOSAB.9.002032 PG 9 WC Optics SC Optics GA JW724 UT WOS:A1992JW72400013 ER PT J AU CARR, R CHABAN, E AF CARR, R CHABAN, E TI PHOSPHOR COATING TECHNIQUE FOR LOW-ENERGY ELECTRON-DIFFRACTION SCREENS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Note AB This article is a presentation of a simple technique for producing very high quality phosphor coatings on curved surfaces such as low-energy electron diffraction collector screens. Our technique involves wetting the screen and dusting it with a powder that adheres uniformly to the wetted surface. We obtain very uniform coatings, which adhere extremely well to stainless steel or to glass. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. RP CARR, R (reprint author), STANFORD SYNCHROTRON RADIAT LAB,POB 4349,BIN 69,STANFORD,CA 94309, USA. NR 3 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD NOV-DEC PY 1992 VL 10 IS 6 BP 3595 EP 3596 PG 2 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA JX920 UT WOS:A1992JX92000036 ER PT J AU KUBIAK, GD KNEEDLER, EM HWANG, RQ SCHULBERG, MT BERGER, KW BJORKHOLM, JE MANSFIELD, WM AF KUBIAK, GD KNEEDLER, EM HWANG, RQ SCHULBERG, MT BERGER, KW BJORKHOLM, JE MANSFIELD, WM TI CHARACTERIZATION OF CHEMICALLY AMPLIFIED RESISTS FOR SOFT-X-RAY PROJECTION LITHOGRAPHY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 36TH ANNUAL INTERNATIONAL SYMP ON ELECTRON, ION, AND PHOTON BEAMS CY MAY 26-29, 1992 CL ORLANDO, FL SP AMER VACCUM SOC, IEEE, ELECTRON DEVICE SOC, OPT SOC AMER, HUGHES RES LABS ID LASER PLASMA SOURCE; EXTREME ULTRAVIOLET; PERFORMANCE AB Sensitivity, lithographic performance, photoabsorption, and photodesorption of chemically amplified novolac-based resists have been studied at an exposure wavelength of 140 angstrom and are compared to poly(methylmethacrylate) (PMMA). Monochromatic exposures of the resists AZ PF514, AZ PN114, and SAL 601 yielded D0.9 values of 2.5-3 mJ/cm2 for 0.25 mum thick films. Contrast values ranged from 3 for AZ PN114 to 5 for SAL 601. Photoabsorption measurements of supported AZ PN114 films at 140 angstrom yield an absorption coefficient of 4.4+/-0.1 mum-1. Photodesorption of fragment ions induced by 140 angstrom radiation has been studied in PMMA and AZ PN114 using time-of-flight mass spectrometry. It is found that H+, CH2+, CH3+, H2O+, CHO+, C3H5+, and COOCH3+ dominate the ion mass spectra photodesorbed from PMMA, while H+, CH3+, H2O+, and CHO+ dominate the ion mass spectra for AZ PN114. The mass-integrated ion desorption yield from AZ PN114 is three times less than that measured for PMMA per photon or 90 times less when expressed per exposure. Lithographic performance of AZ PF514 and SAL 601 has been characterized using a multilayer-coated 20X Schwarzschild objective and a transmissive Ge/Si mask illuminated by a laser plasma source. C1 AT&T BELL LABS,HOLMDEL,NJ 07733. UNIV OREGON,DEPT PHYS,EUGENE,OR 97403. RP KUBIAK, GD (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. NR 20 TC 15 Z9 15 U1 1 U2 4 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 NOV-DEC PY 1992 VL 10 IS 6 BP 2593 EP 2599 DI 10.1116/1.586333 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA KM500 UT WOS:A1992KM50000044 ER PT J AU KING, O ERDOGAN, T WICKS, GW HALL, DG ANDERSON, EH COSTELLO, D ROOKS, MJ AF KING, O ERDOGAN, T WICKS, GW HALL, DG ANDERSON, EH COSTELLO, D ROOKS, MJ TI CURVED GRATING FABRICATION TECHNIQUES FOR SURFACE-EMITTING DISTRIBUTED FEEDBACK LASERS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 36TH ANNUAL INTERNATIONAL SYMP ON ELECTRON, ION, AND PHOTON BEAMS CY MAY 26-29, 1992 CL ORLANDO, FL SP AMER VACCUM SOC, IEEE, ELECTRON DEVICE SOC, OPT SOC AMER, HUGHES RES LABS ID ZONE PLATES AB We report on techniques for the fabrication of curved waveguide diffraction gratings for use in novel semiconductor laser structures. In particular, we consider the development of concentric-circle gratings to be employed in circularly symmetric, surface-emitting semiconductor lasers. The gratings are defined using electron-beam lithography and subsequently etched into the semiconductor surface by chemically assisted ion-beam etching. Issues to be addressed include grating design requirements, pattern representation, and scan method. We provide examples of how these techniques can be implemented and their impact on the resulting laser performance. C1 IBM CORP,THOMAS J WATSON RES CTR,YORKTOWN HTS,NY 10598. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. CORNELL UNIV,NATL NANOFABRICAT FACIL,ITHACA,NY 14853. RP KING, O (reprint author), UNIV ROCHESTER,INST OPT,ROCHESTER,NY 14627, USA. NR 8 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 NOV-DEC PY 1992 VL 10 IS 6 BP 2974 EP 2978 DI 10.1116/1.585955 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA KM500 UT WOS:A1992KM50000125 ER PT J AU TENNANT, DM FETTER, LA HARRIOTT, LR MACDOWELL, AA MULGREW, PP WASKIEWICZ, WK WINDT, DL WOOD, OR AF TENNANT, DM FETTER, LA HARRIOTT, LR MACDOWELL, AA MULGREW, PP WASKIEWICZ, WK WINDT, DL WOOD, OR TI DEFECT REPAIR FOR SOFT-X-RAY PROJECTION LITHOGRAPHY MASKS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 36TH ANNUAL INTERNATIONAL SYMP ON ELECTRON, ION, AND PHOTON BEAMS CY MAY 26-29, 1992 CL ORLANDO, FL SP AMER VACCUM SOC, IEEE, ELECTRON DEVICE SOC, OPT SOC AMER, HUGHES RES LABS AB The most promising option for masks intended for use in soft x-ray projection lithography (SXPL) at lambda=13 nm is a reflective mask which uses a Mo/Si multilayer reflective coating. A variety of multilayer coated reflective mask technologies have been reported which can provide both high-resolution features and good reflectance contrast between the patterned and unpatterned regions. Repair of defects generated during patterning is a necessary feature of any practical mask technology. We have investigated the application of focused ion beam milling and deposition to programmed defects in the absorber layer of a SXPL Mo/Si multilayer reflection mask. Use of a sacrificial polymer barrier layer is described as well as milling and deposition conditions. The effect of ion implantation of the barrier layer on its removal after absorber repair is also reported. Both reflectivity measurements and resist images comparing repaired and unrepaired regions of masks are used to demonstrate the efficacy of the technique. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP TENNANT, DM (reprint author), AT&T BELL LABS,HOLMDEL,NJ 07733, USA. NR 7 TC 10 Z9 10 U1 3 U2 3 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 NOV-DEC PY 1992 VL 10 IS 6 BP 3134 EP 3140 DI 10.1116/1.585943 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA KM500 UT WOS:A1992KM50000155 ER PT J AU JACOBSEN, C HOWELLS, M AF JACOBSEN, C HOWELLS, M TI PROJECTION X-RAY-LITHOGRAPHY USING COMPUTER-GENERATED HOLOGRAMS - A STUDY OF COMPATIBILITY WITH PROXIMITY LITHOGRAPHY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 36TH ANNUAL INTERNATIONAL SYMP ON ELECTRON, ION, AND PHOTON BEAMS CY MAY 26-29, 1992 CL ORLANDO, FL SP AMER VACCUM SOC, IEEE, ELECTRON DEVICE SOC, OPT SOC AMER, HUGHES RES LABS ID IMAGE AB X-ray projection lithography has recently been explored as a method for the manufacture of < 200 nm linewidth integrated circuits. A method was previously described [J. Appl. Phys. 71, 2993 (1992)] whereby projected lithographic images can be formed with x rays by means of a transmission hologram. The form of the hologram is computed by an algorithm which eliminates the unwanted signals normally present as systematic errors in in-line holographic images. Such an approach to projection x-ray lithography requires an x-ray beam with very little coherence and is thus compatible with high wafer throughput schemes; in addition, image fidelity remains high even when moderately small contaminant particles block the light from small regions of the hologram. Previous example calculations involved using 5 nm x rays to illuminate a 0-1 mum thick carbon hologram located 200 mum from the wafer to produce simulated 0.06 mum linewidth images with good fidelity and with 6 mum depth of field. Presented here are simulations involving holographic masks made of 0-1 mum of tungsten operating at 1 nm wavelength with 50 mum mask-to-wafer gap. Such a configuration can be viewed as a future extension of the existing technology of proximity x-ray lithography to linewidths as small as 0.02 mum. C1 LAWRENCE BERKELEY LAB,EXPTL SYST GRP,BERKELEY,CA 94720. RP JACOBSEN, C (reprint author), SUNY STONY BROOK,DEPT PHYS,STONY BROOK,NY 11794, USA. RI Jacobsen, Chris/E-2827-2015 OI Jacobsen, Chris/0000-0001-8562-0353 NR 16 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 1992 VL 10 IS 6 BP 3177 EP 3181 DI 10.1116/1.585907 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA KM500 UT WOS:A1992KM50000164 ER PT J AU HAWRYLUK, AM STEWART, D AF HAWRYLUK, AM STEWART, D TI REPAIR OF OPAQUE DEFECTS ON REFLECTION MASKS FOR SOFT-X-RAY PROJECTION LITHOGRAPHY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 36TH ANNUAL INTERNATIONAL SYMP ON ELECTRON, ION, AND PHOTON BEAMS CY MAY 26-29, 1992 CL ORLANDO, FL SP AMER VACCUM SOC, IEEE, ELECTRON DEVICE SOC, OPT SOC AMER, HUGHES RES LABS AB We have developed a new technique for removing opaque defects on soft x-ray projection lithography reflection masks using ion beam etching. This technique clears the defect without damaging the multilayer mirror or introducing an absorptive element into the multilayer. Our procedure uses a thin, Si overcoat to protect the multilayers from the kinetic energy of the ion beam, reduced ion beam energy, and a Ar ion beam to avoid absorption losses. A Si ion beam could also be used in this process. C1 MICRION CORP,PEABODY,MA 01960. RP HAWRYLUK, AM (reprint author), LAWRENCE LIVERMORE NATL LAB,LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551, USA. NR 5 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 NOV-DEC PY 1992 VL 10 IS 6 BP 3182 EP 3185 DI 10.1116/1.585908 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA KM500 UT WOS:A1992KM50000165 ER PT J AU LAMBERT, SJ EPSTEIN, S AF LAMBERT, SJ EPSTEIN, S TI STABLE-ISOTOPE STUDIES OF ROCKS AND SECONDARY MINERALS IN A VAPOR-DOMINATED HYDROTHERMAL SYSTEM AT THE GEYSERS, SONOMA COUNTY, CALIFORNIA SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Article ID OXYGEN ISOTOPE; HYDROGEN ISOTOPE; GEOTHERMAL SYSTEM; ULTRAMAFIC ROCKS; CARBON ISOTOPE; FRACTIONATION; WATER; GEOCHEMISTRY; SERPENTINIZATION; FRANCISCAN AB The Geysers, a vapor-dominated hydrothermal system, is developed in host rock of the Franciscan Formation, which contains veins of quartz and calcite whose deltaO-18 values record the temperatures and isotopic compositions of fluids prevailing during at least two different episodes of rock-fluid interaction. The first episode took place at about 200-degrees-C, during which marine silica and carbonate apparently interacted with ocean water entrapped in the sediments to form veins of quartz and calcite whose deltaO-18 values were around + 19 and + 16 parts per thousand, respectively. The calculated water/mineral ratios were less than unity. The water may have profoundly influenced the deltaO-18 values of spilitic basalts during their metamorphism to greenstones. Serpentinization and structural emplacement of ophiolite slabs were isotopically unrelated to this episode, which was essentially a low-grade (post-Cretaceous?) burial metamorphism. D/H ratios of actinolite, chlorite, and micas in host rocks were more profoundly altered during this episode than were O-18/O-16 ratios. A paleogeothermal gradient of about 53-degrees-C/km has been inferred for this episode, from deltaO-18-depth distributions of vein minerals. The second episode, in part recorded by cogenetic vein quartz and calcite deltaO-18 values of +4 to +6 parts per thousand and + 1 to + 30 parts per thousand, respectively, began with large quantities of meteoric water circulating in fractures in the rock at temperatures of 160-180-degrees-C in response to the initiation of the Pliocene-Pleistocene Clear Lake magmatism. The temperature rose, and with the restricted circulation of fluids the ancestral hot-water system evolved into the presently active vapor-dominated system, which according to the cogenetic vein quartz and calcite deltaO-18 values involved temperatures as high as 320-degrees-C and fluid/mineral ratios near unity. The change in the oxygen-isotopic composition of the serpentinite within the host rock during this later activity was negligible. The deltaC-13 values of vein calcite at The Geysers reflect both a marine carbonate and organic component of carbon, but carbon-isotope exchange has been facilitated by the vapor-dominated hydrothermal fluid to a greater degree than in any other episode or in other hot-water systems. C1 CALTECH,DIV GEOPHYS & PLANETARY SCI,PASADENA,CA 91125. RP LAMBERT, SJ (reprint author), SANDIA NATL LABS,DIV GEOCHEM 6233,ALBUQUERQUE,NM 87185, USA. NR 48 TC 8 Z9 8 U1 1 U2 4 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 NOV PY 1992 VL 53 IS 1-4 BP 199 EP 226 DI 10.1016/0377-0273(92)90082-O PG 28 WC Geosciences, Multidisciplinary SC Geology GA KE866 UT WOS:A1992KE86600013 ER PT J AU VOLPE, AM AF VOLPE, AM TI U-238 TH-230-RA-226 DISEQUILIBRIUM IN YOUNG MT SHASTA ANDESITES AND DACITES SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Article ID EAST PACIFIC RISE; VOLCANIC-ROCKS; TH-230-U-238 DISEQUILIBRIUM; RADIOACTIVE DISEQUILIBRIA; PLAGIOCLASE PHENOCRYSTS; CASCADE MOUNTAINS; MASS-SPECTROMETRY; MAGMA FORMATION; ST-HELENS; TH AB The paper describes U-238-series nuclides and Th-230/Th-232 ratios measured by mass spectrometry in mineral separates of young Mt. Shasta andesites and dacites. The results constrain the timing of recent calc-alkaline magma fractionation at this volcano. Hotlum, Misery Hill and Black Butte rocks show small, < 13% Th-230-U-238 and < 6% Ra-226-Th-230, disequilibria. Plagioclase have 7-26% 226 Ra excesses, magnetite and groundmass have 4-5% Ra-226 deficits, and pyroxenes have equilibrium (Ra-226/Th-230) activity ratios. Internal (Th-230)-(U-238) and Ba-normalized (Ra-226)-(Th-230) isotope diagrams for Hotlum and Black Butte dacites suggest that closed-system Th-U and Ra-Th fractionation occurred less than 10,000 years ago. Significant Ra-226-Th-230 disequilibria in the Black Butte dacite strongly suggests that this rock erupted more recently than 9400 years ago. Results for Hotlum andesites suggest a longer pre-eruption crystal residence time compared to the dacites. There may also have been recent open Ra-Th system changes in the melt composition. Initial Th/U ratios for the rocks are low (2.43-2.57), similar to those in mid-ocean ridge basalts (MORB), and preclude significant assimilation of crust with markedly different Th-U composition. RP VOLPE, AM (reprint author), LAWRENCE LIVERMORE NATL LAB,L-232,LIVERMORE,CA 94550, USA. NR 44 TC 43 Z9 43 U1 0 U2 2 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 NOV PY 1992 VL 53 IS 1-4 BP 227 EP 238 DI 10.1016/0377-0273(92)90083-P PG 12 WC Geosciences, Multidisciplinary SC Geology GA KE866 UT WOS:A1992KE86600014 ER PT J AU ORSI, G GALLO, G HEIKEN, G WOHLETZ, K YU, E BONANI, G AF ORSI, G GALLO, G HEIKEN, G WOHLETZ, K YU, E BONANI, G TI A COMPREHENSIVE STUDY OF PUMICE FORMATION AND DISPERSAL - THE CRETAIO TEPHRA OF ISCHIA (ITALY) SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Article ID VOLCANIC ASH; CALIBRATION; PRECISION; CALDERA; C-14 AB The Cretaio Tephra is a small-volume (< 0.02 km3) pumice deposit on the island of Ischia in Italy. It was erupted during historical time and is associated with a tuff ring-dome complex extruded along a N-S-trending normal fault system bordering the east side of the Mt. Epomeo resurgent block. C-14 ages of the deposit average 1860 a B.P., which is in agreement with the potsherds found in paleosols underlying and overlying the deposit. The eruption sequence consists of 7 members; most of these members are pumice fall deposits, one is an ash and pumice fallout and another is a surge bed. The tephra have a trachytic-phonolitic composition. All chemical characteristics, including major and trace elements, and Sr-isotope composition are homogeneous throughout the sequence. The vesicularity of pumice clasts does not show any systematic change; the erupted magma had the same amount of volatiles, the same flux and vesicle growth behavior throughout the eruption sequence. Grain-size analyses of 90 tephra samples, representative of all the members at variable distance from the supposed vent, have been processed using the Sequential Fragmentation/Transport theory in order to define the effects of eruptive fragmentation and subsequent transport on the particle sizes distribution. Four significant subpopulations have been identified and related to transport mechanisms. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. SWISS FED INST TECHNOL,INST MITTELENERGIEPHYS,CH-8092 ZURICH,SWITZERLAND. RP ORSI, G (reprint author), NAPLES UNIV,DIPARTIMENTO GEOFIS & VULCANOL,LARGO S MARCELLINO 10,I-80138 NAPLES,ITALY. NR 29 TC 44 Z9 46 U1 0 U2 3 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 NOV PY 1992 VL 53 IS 1-4 BP 329 EP 354 DI 10.1016/0377-0273(92)90090-Z PG 26 WC Geosciences, Multidisciplinary SC Geology GA KE866 UT WOS:A1992KE86600021 ER PT J AU WARNER, HR CAMPISI, J CRISTOFALO, VJ MILLER, RA PAPACONSTANTINOU, J PEREIRASMITH, O SMITH, JR WANG, E AF WARNER, HR CAMPISI, J CRISTOFALO, VJ MILLER, RA PAPACONSTANTINOU, J PEREIRASMITH, O SMITH, JR WANG, E TI CONTROL OF CELL-PROLIFERATION IN SENESCENT CELLS SO JOURNALS OF GERONTOLOGY LA English DT Editorial Material C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. MED COLL PENN,PHILADELPHIA,PA 19129. UNIV MICHIGAN,ANN ARBOR,MI 48109. UNIV TEXAS,MED BRANCH,GALVESTON,TX 77550. BAYLOR COLL MED,HOUSTON,TX 77030. LADY DAVIS INST MED RES,MONTREAL,QUEBEC,CANADA. RP WARNER, HR (reprint author), NIA,BETHESDA,MD 20892, USA. RI Papaconstantinou, John/E-3312-2010 NR 0 TC 6 Z9 6 U1 0 U2 0 PU GERONTOLOGICAL SOCIETY AMER PI WASHINGTON PA 1275 K STREET NW SUITE 350, WASHINGTON, DC 20005-4006 SN 0022-1422 J9 J GERONTOL JI J. Gerontol. PD NOV PY 1992 VL 47 IS 6 BP B185 EP B189 PG 5 WC Geriatrics & Gerontology; Gerontology SC Geriatrics & Gerontology GA JX157 UT WOS:A1992JX15700015 PM 1430846 ER PT J AU WILSON, TE OGLETREE, DF SALMERON, MB BEDNARSKI, MD AF WILSON, TE OGLETREE, DF SALMERON, MB BEDNARSKI, MD TI EVALUATION OF THE STRUCTURE OF POLYDIACETYLENE MONOLAYERS USING FLUORESCENCE MICROSCOPY AND SCANNING TUNNELING MICROSCOPY SO LANGMUIR LA English DT Letter ID TUNNELLING MICROSCOPY; DNA; GRAPHITE; BIOMEMBRANES; SURFACES; MODELS AB This communication describes a structural study of polydiacetylene monolayers supported on highly-oriented pyrolytic graphite (HOPG). Both scanning tunneling microscopy (STM) and scanning laser confocal fluorescence microscopy were used to evaluate monolayer structure at the micrometer level. These studies demonstrate that extreme tunneling conditions (10 pA, 10 V) may be required to obtain images that are consistent with those of high-resolution fluorescence microscopy results. STM imaging using lower values of gap resistance damaged or removed the organic monolayer from the graphite surface. The correlation between optical and scanned microscopies clearly indicates the utility of STM for studying the structure of polydiacetylene films. C1 LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720. RP WILSON, TE (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720, USA. NR 22 TC 7 Z9 7 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD NOV PY 1992 VL 8 IS 11 BP 2588 EP 2590 DI 10.1021/la00047a002 PG 3 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA JZ534 UT WOS:A1992JZ53400002 ER PT J AU ECKHARDT, CJ PEACHEY, NM SWANSON, DR KIM, JH WANG, J UPHAUS, RA LUTZ, GP BEAK, P AF ECKHARDT, CJ PEACHEY, NM SWANSON, DR KIM, JH WANG, J UPHAUS, RA LUTZ, GP BEAK, P TI CRYSTAL ENGINEERING IN 2 DIMENSIONS - DESIGN OF AMPHIPHILES FOR ORDERED FILMS SO LANGMUIR LA English DT Article ID LANGMUIR-BLODGETT-FILMS; ATOMIC FORCE MICROSCOPY; MOLECULAR-RESOLUTION IMAGES; MONOLAYERS AB The results of an experimental and calculative study of a new, rigidified amphiphile designed to form a well-ordered, two-dimensional Langmuir-Blodgett monolayer crystal are reported. The packing of the amphiphile is shown by atomic force microscopy to be closer to hexagonal than found for a stearic acid monolayer. The true planar space group is pl. The results essentially mirror those obtained from an atom-atom potential calculation of the packing of the amphiphile. The investigation demonstrates the utility of designing amphiphiles to 'engineer" specific planar lattices. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. UNIV ILLINOIS,DEPT CHEM,URBANA,IL 61801. RP ECKHARDT, CJ (reprint author), UNIV NEBRASKA,DEPT CHEM,LINCOLN,NE 68588, USA. NR 16 TC 16 Z9 16 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD NOV PY 1992 VL 8 IS 11 BP 2591 EP 2594 DI 10.1021/la00047a003 PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA JZ534 UT WOS:A1992JZ53400003 ER PT J AU SMITH, EL ALVES, CA ANDEREGG, JW PORTER, MD SIPERKO, LM AF SMITH, EL ALVES, CA ANDEREGG, JW PORTER, MD SIPERKO, LM TI DEPOSITION OF METAL OVERLAYERS AT END-GROUP-FUNCTIONALIZED THIOLATE MONOLAYERS ADSORBED AT AU .1. SURFACE AND INTERFACIAL CHEMICAL CHARACTERIZATION OF DEPOSITED CU-OVERLAYERS AT CARBOXYLIC ACID-TERMINATED STRUCTURES SO LANGMUIR LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; ORGANIZED MOLECULAR ASSEMBLIES; SCANNING TUNNELING MICROSCOPY; INFRARED-SPECTROSCOPY; OPTICAL ELLIPSOMETRY; SECONDARY ADSORBATES; CONSISTENT SERIES; ELECTRON-TRANSFER; GOLD SURFACES; ACETIC-ACID AB This paper describes the preparation and characterization of interfacial structures formed by the deposition of thin (approximately 0.2 and 5 nm) overlayer films of Cu at carboxylic acid-teminated thiolate monolayers adsorbed at Au. Infrared reflection spectroscopy (IRS), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) have been used to probe both compositional and structural details of the interfaces. The monolayers are formed by the chemisorption of carboxylic acid-terminated alkanethiols (HO2C-(CH2)nSH, n = 10 and 15) from dilute ethanolic solutions at the surface of evaporated Au films. Prior to Cu deposition, the IRS data indicate that the polymethylene chains form a densely packed surface phase for n = 15 and a more disordered surface phase for n = 10. For n = 10 and n = 15, the terminal carboxylic acids exist in both free and hydrogen-bonded forms. Deposition of a Cu overlayer by resistive evaporation and subsequent exposure to the laboratory ambient leads to the formation of a carboxylate salt as revealed by the detection of both the nua(COO-) and nus(COO-) modes by IRS. The IRS data also show that Cu deposition induces disorder in the underlying polymethylene chain structure relative to that of the uncoated monolayer. Both the XPS and IRS data reveal that Cu is bound in its +2 oxidation state to the carboxylate. Images from AFM indicate that the crystallite size (approximately 20 nm) of the Cu overlayer is markedly less than that (approximately 200-300 nm) of anchoring metal substrate. The potential application of this adsorbate-substrate system to fundamental studies of the adhesion of metal overlayers at surface functionalized polymeric materials is briefly discussed. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IBM CORP,ADV TECHNOL LAB,ENDICOTT,NY 13760. NR 62 TC 140 Z9 141 U1 3 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD NOV PY 1992 VL 8 IS 11 BP 2707 EP 2714 DI 10.1021/la00047a021 PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA JZ534 UT WOS:A1992JZ53400021 ER PT J AU SALMERON, M FOLCH, A NEUBAUER, G TOMITORI, M OGLETREE, DF KOLBE, W AF SALMERON, M FOLCH, A NEUBAUER, G TOMITORI, M OGLETREE, DF KOLBE, W TI NANOMETER SCALE MECHANICAL-PROPERTIES OF AU(111) THIN-FILMS SO LANGMUIR LA English DT Article ID SCANNING TUNNELING MICROSCOPY; ATOMIC FORCE MICROSCOPY; SURFACE FORCES; OPTICAL INTERFEROMETRY; CONTACT; TIP AB The mechanical properties of gold films of (111) orientation were studied as a function of load when contacted by a single asperity Pt-Rh alloy tip. The interaction forces were measured in the direction perpendicular to the surface. The contribution of various types of forces (van der Waals, capillarity from contaminants, and metallic adhesion) in the process of contact was determined. We investigated the elastic and plastic response of the gold film as a function of applied load by examination of the contact area in subsequent imaging with STM and AFM. C1 UNIV BARCELONA,DEPT FIS,BARCELONA 7,SPAIN. LAWRENCE BERKELEY LAB,DIV ENGN,BERKELEY,CA 94720. RP SALMERON, M (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720, USA. NR 31 TC 30 Z9 30 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD NOV PY 1992 VL 8 IS 11 BP 2832 EP 2842 DI 10.1021/la00047a041 PG 11 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA JZ534 UT WOS:A1992JZ53400041 ER PT J AU MULHOLLAND, PJ AF MULHOLLAND, PJ TI REGULATION OF NUTRIENT CONCENTRATIONS IN A TEMPERATE FOREST STREAM - ROLES OF UPLAND, RIPARIAN, AND INSTREAM PROCESSES SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Article ID WOODLAND STREAM; PHOSPHORUS DYNAMICS; DECIDUOUS FOREST; SURFACE-WATER; ECOSYSTEM; SEDIMENTS; TRANSPORT; RETENTION; ZONE AB The roles of terrestrial and instream processes in controlling stream-water N and P concentrations were studied over a 2-yr period in a deciduous forest stream in eastern Tennessee. Upper soil horizons were highly effective sinks for inorganic N and P in throughfall, and weathering of the parent dolomite was the dominant source of inorganic P to the stream. The riparian zone was a potential source of NH4+ and P to the stream when dissolved oxygen concentrations in riparian groundwater were low, but a sink for P when dissolved oxygen concentrations were high. High rates of instream immobilization of inorganic N and P were observed from late autumn to spring, primarily as a result of uptake by microbes on decomposing leaves and secondarily by algae. Immobilization of inorganic N and P resulted in longitudinal declines in concentrations with distance downstream from groundwater inputs (springs), thereby increasing the importance of organic forms of these nutrients in stream water in downstream reaches. The seasonal pattern of winter minima and summer maxima in stream-water N and P concentrations observed here is opposite to the pattern observed in many northern streams, suggesting the importance of winter nutrient cycling processes in soils and streams in warmer climates. RP MULHOLLAND, PJ (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,OAK RIDGE,TN 37831, USA. RI Mulholland, Patrick/C-3142-2012 NR 39 TC 184 Z9 186 U1 4 U2 43 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 NOV PY 1992 VL 37 IS 7 BP 1512 EP 1526 PG 15 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA KM341 UT WOS:A1992KM34100012 ER PT J AU NOID, DW SUMPTER, BG AF NOID, DW SUMPTER, BG TI EXISTENCE OF NONLINEAR RESONANCES IN POLYETHYLENE SO MAKROMOLEKULARE CHEMIE-THEORY AND SIMULATIONS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; H STRETCHING REGION; POLYMETHYLENE CHAIN; VIBRATIONAL-ENERGY; FERMI RESONANCE; FORCE-FIELD; SYSTEMS; SPECTRA; CRYSTAL AB In this paper, we demonstrate that the internal dynamics and vibrational spectra of polyethylene are influenced by Fermi and other nonlinear resonances. In previous work, the first semiclassical theory and quantum numbers (in parabolic coordinates) appropriate for this type of resonance were developed. We find from detailed molecular dynamics simulations that the same types of quantum numbers are applicable for polyethylene stretch-bend mode interactions. In addition, a one-to-one resonance is found to exist from one local C-H stretch to another C-H stretch along the polymer chain. C1 UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. RP NOID, DW (reprint author), OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831, USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 37 TC 4 Z9 4 U1 0 U2 0 PU HUTHIG & WEPF VERLAG PI BASEL PA AUF DEM WOLF 4, CH-4052 BASEL, SWITZERLAND SN 1018-5054 J9 MAKROMOL CHEM-THEOR PD NOV PY 1992 VL 1 IS 6 BP 359 EP 374 PG 16 WC Polymer Science SC Polymer Science GA JZ515 UT WOS:A1992JZ51500002 ER PT J AU CARLSON, NM JOHNSON, JA LOTT, LA KUNERTH, DC AF CARLSON, NM JOHNSON, JA LOTT, LA KUNERTH, DC TI ULTRASONIC NDT METHODS FOR WELD SENSING SO MATERIALS EVALUATION LA English DT Article DE CONCURRENT INSPECTION; DEFECT DETECTION; ELECTROMAGNETIC ACOUSTIC TRANSDUCER; FINITE ELEMENT; LASER SOUND GENERATION; NONCONTACT ULTRASONIC SENSING; PIEZOELECTRIC TRANSDUCER; PROCESS CONTROL; RAY TRACING; THERMAL GRADIENT CODE; ULTRASONIC SENSING AB Process control of welding at the Idaho National Engineering Laboratory (INEL) uses ultrasonic sensing techniques to defect the quality of the welding process. Initial feasibility work in ultrasonic sensing of the molten pool was done with immersion tank techniques. The weld quality of solidified weld metal is concurrently inspected on a pass-by-pass basis by a contacting ultrasonic system that trails the welding electrode. The welding process is monitored with piezoelectric transducers mounted on lucite wedges; longitudinal waves detect defect conditions in the molten weld pool and shear waves determine the geometry of the molten/solid interface. Current work involves noncontact ultrasonic sensing techniques using a pulsed laser for sound generation and an electromagnetic acoustic transducer for detection of weld quality of the molten pool and the solidified weld metal. RP CARLSON, NM (reprint author), IDAHO NATL ENGN LAB,POB 1625,IDAHO FALLS,ID 83415, USA. NR 13 TC 14 Z9 14 U1 2 U2 5 PU AMER SOC NON-DESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD NOV PY 1992 VL 50 IS 11 BP 1338 EP 1343 PG 6 WC Materials Science, Characterization & Testing SC Materials Science GA JX523 UT WOS:A1992JX52300008 ER PT J AU WOFSY, C GOLDSTEIN, B AF WOFSY, C GOLDSTEIN, B TI INTERPRETATION OF SCATCHARD PLOTS FOR AGGREGATING RECEPTOR SYSTEMS SO MATHEMATICAL BIOSCIENCES LA English DT Article ID GROWTH-FACTOR RECEPTORS; LIGAND-BINDING SYSTEMS; IMMUNOGLOBULIN-E; HIGH-AFFINITY; CELL-SURFACE; DISSOCIATION KINETICS; MOLECULAR-BASIS; CROSS-LINKING; ACTIVATION; EQUILIBRIUM AB Aggregation of cell surface receptors, with each other or with other membrane proteins, occurs in a variety of experimental systems. The list of systems where receptor aggregation appears to be important in understanding ligand binding and cellular responses is growing rapidly. In this paper we explore the interpretation of equilibrium binding data for aggregating receptor systems. The Scatchard plot is a widely used tool for analyzing equilibrium binding data. The shape of the Scatchard plot is often interpreted in terms of multiple noninteracting receptor populations. Such an analysis does not provide a framework for investigating the role of receptor aggregation and will be misleading if there is a relation between receptor aggregation and ligand binding. We present a general model for the equilibrium binding of a ligand with any number of aggregating receptor populations and derive theoretical expressions for observable Scatchard plot features. These can be used to test particular models and estimate model parameters. We develop particular models and apply the general results in the cases of six aggregating receptor systems where ligand binding and receptor aggregation are related: cross-linking of monovalent cell surface proteins by monoclonal antibodies, cross-linking of cell surface antibodies by bivalent ligand, antibody-induced co-cross-linking of cell surface antibodies and Fc(gamma) receptors, ligand-enhanced aggregation of identical epidermal growth factor receptors, aggregation of heterologous receptors for interleukin 2 to form a high-affinity receptor, and association of receptors, including those for interleukins 5 and 6, with nonbinding accessory proteins that influence receptor affinity or effector function. C1 LOS ALAMOS NATL LAB,DIV THEORET,THEORET BIOL & BIOPHYS GRP,LOS ALAMOS,NM 87545. RP WOFSY, C (reprint author), UNIV NEW MEXICO,DEPT MATH & STAT,ALBUQUERQUE,NM 87131, USA. FU NIGMS NIH HHS [GM35556] NR 25 TC 19 Z9 19 U1 0 U2 6 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0025-5564 J9 MATH BIOSCI JI Math. Biosci. PD NOV PY 1992 VL 112 IS 1 BP 115 EP 154 DI 10.1016/0025-5564(92)90090-J PG 40 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA JY503 UT WOS:A1992JY50300005 PM 1330105 ER PT J AU COAKLEY, KJ AF COAKLEY, KJ TI SPATIAL STATISTICS FOR PREDICTING FLUID-FLOW THROUGH A SINGLE ROCK FRACTURE SO MATHEMATICAL GEOLOGY LA English DT Article DE SPATIAL STATISTICS; SINGLE ROCK FRACTURE; FLUID FLOW; PREDICTION ID PERMEABILITY AB Steady-state laminar flow through single rock fractures is predicted in terms of spatial statistics computed from the arrangement of voids and contact areas within the fracture. Within the voids, aperture is assumed to be constant. One statistic measures how often pixels alternate from void to contact area in the rows parallel to the flow direction. Two others measure the dispersion of voids in the rows and columns of the pattern. Fractures with complexity typical of observed data are simulated. Flow through patterns with 80% voids is predicted in terms of a linear combination of the three statistics. Using an extended model involving one of the three statistics, flow through patterns with other void fractions is predicted. C1 LAWRENCE BERKELEY LAB,DIV EARTH SCI,BERKELEY,CA 94720. RP COAKLEY, KJ (reprint author), NATL INST STAND & TECHNOL,DIV STAT ENGN,GAITHERSBURG,MD 20899, USA. NR 19 TC 1 Z9 1 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 NOV PY 1992 VL 24 IS 8 BP 905 EP 927 DI 10.1007/BF00894658 PG 23 WC Geosciences, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Geology; Mathematics GA JU450 UT WOS:A1992JU45000003 ER PT J AU LAIRD, G EPSTEIN, JS AF LAIRD, G EPSTEIN, JS TI FRACTURE-MECHANICS AND FINITE-ELEMENT ANALYSIS SO MECHANICAL ENGINEERING LA English DT Article RP LAIRD, G (reprint author), US BUR MINES,ALBANY RES CTR,ALBANY,OR, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0025-6501 J9 MECH ENG JI Mech. Eng. PD NOV PY 1992 VL 114 IS 11 BP 69 EP 73 PG 5 WC Engineering, Mechanical SC Engineering GA JY351 UT WOS:A1992JY35100020 ER PT J AU CHAN, KS BODNER, SR FOSSUM, AF MUNSON, DE AF CHAN, KS BODNER, SR FOSSUM, AF MUNSON, DE TI A CONSTITUTIVE MODEL FOR INELASTIC FLOW AND DAMAGE EVOLUTION IN SOLIDS UNDER TRIAXIAL COMPRESSION SO MECHANICS OF MATERIALS LA English DT Article ID CRACK-TIP FIELDS; CREEP-RUPTURE; EQUATIONS; FRACTURE AB A constitutive model for describing time-dependent, pressure-sensitive inelastic flow and damage evolution in crystalline solids under non-hydrostatic compression has been developed on the basis that the relevant damage and dislocation flow processes both contribute to the overall inelastic strain rate. A damage-based kinetic equation is first formulated using the work-conjugate approach and the continuum damage concept. That relation is then added to the dislocation-based kinetic equation of a multi-mechanism deformation (M-D) model to obtain the macroscopic inelastic strain rate. The proposed kinetic relation for the overall inelastic strain rate is shown to be derivable from a flow potential. The kinetic equation indicates plastic dilatancy under triaxial compression when the damage term is activated, and leads to plastic incompressibility when inelastic straining is primarily provided by dislocation flow mechanisms. The dependence of creep rate and plastic dilatancy on confining pressure shown by model calculations for rock salt is in accordance with experimental observations. C1 SPEC INC,RE,RAPID CITY,SD 57709. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP CHAN, KS (reprint author), SW RES INST,62220 CULEBRA RD,PO DRAWER 28510,SAN ANTONIO,TX 78228, USA. NR 31 TC 48 Z9 49 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6636 J9 MECH MATER JI Mech. Mater. PD NOV PY 1992 VL 14 IS 1 BP 1 EP 14 DI 10.1016/0167-6636(92)90014-5 PG 14 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA JZ264 UT WOS:A1992JZ26400001 ER PT J AU ZIMMERMAN, RW AF ZIMMERMAN, RW TI HASHIN-SHTRIKMAN BOUNDS ON THE POISSON RATIO OF A COMPOSITE-MATERIAL SO MECHANICS RESEARCH COMMUNICATIONS LA English DT Article RP ZIMMERMAN, RW (reprint author), LAWRENCE BERKELEY LAB,DIV EARTH SCI,BERKELEY,CA 94720, USA. OI Zimmerman, Robert/0000-0001-6674-3403 NR 10 TC 27 Z9 28 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0093-6413 J9 MECH RES COMMUN JI Mech. Res. Commun. PD NOV-DEC PY 1992 VL 19 IS 6 BP 563 EP 569 DI 10.1016/0093-6413(92)90085-O PG 7 WC Mechanics SC Mechanics GA JZ927 UT WOS:A1992JZ92700011 ER PT J AU SLATKIN, DN SPANNE, P DILMANIAN, FA SANDBORG, M AF SLATKIN, DN SPANNE, P DILMANIAN, FA SANDBORG, M TI MICROBEAM RADIATION-THERAPY SO MEDICAL PHYSICS LA English DT Article DE X-RAY; MICROBEAM; RADIOTHERAPY; BRAIN; SYNCHROTRON ID COHERENT; PHOTONS AB It is proposed to carry out radiotherapy and radiosurgery for brain lesions by crossfiring an array of parallel, closely spaced microbeams of synchrotron-generated x rays several times through an isocentric target, each microbeam in the array having an almost-equal-to 25-mum-wide adjustable-height rectangular cross section. The following inferences from the known tissue sparing of 22-MeV deuteron microbeams in the mouse brain and the following exemplary Monte Carlo computations indicate that endothelial cells in the brain that are lethally irradiated by any microbeam in an array of adequately spaced microbeams outside an isocentric target will be replaced by endothelial cells regenerated from microscopically contiguous, minimally irradiated endothelium in intermicrobeam segments of brain vasculature. Endothelial regeneration will prevent necrosis of the nontargeted parenchymal tissue. However, neoplastic and/or nonneoplastic targeted tissues at the isocenter will be so severely depleted of potentially mitotic endothelial and parenchymal cells by multiple overlapping microbeams that necrosis will ensue. The Monte Carlo computations simulate microbeam irradiations of a 16-cm diameter, 16-cm-long cylindrical human head phantom using 50-, 100-, and 150-keV monochromatic x rays. C1 BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973. LINKOPING UNIV,DEPT RADIAT PHYS,S-58185 LINKOPING,SWEDEN. RP SLATKIN, DN (reprint author), BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973, USA. NR 31 TC 143 Z9 144 U1 1 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0094-2405 J9 MED PHYS JI Med. Phys. PD NOV-DEC PY 1992 VL 19 IS 6 BP 1395 EP 1400 DI 10.1118/1.596771 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA JY761 UT WOS:A1992JY76100006 PM 1461201 ER PT J AU WIELOPOLSKI, L REN, XM AF WIELOPOLSKI, L REN, XM TI HIGH-ENERGY X-RAY-BEAM CHARACTERIZATION USING PHOTONUCLEAR REACTION SO MEDICAL PHYSICS LA English DT Article DE MEDICAL ACCELERATOR; PHOTOACTIVATION; HIGH-ENERGY BEAM ID BREMSSTRAHLUNG; ELECTRONS; SPECTRA; TARGETS AB Spectral changes in the primary photon beam of a high-energy medical electron accelerator have been monitored using photonuclear reactions. The beam across the radiation field was measured using induced activity in Teflon cylinder and copper foil samples at several off-axis angles, at different SSDs in air and in a solid water phantom. The induced activities of the positron emitters were measured using a coincidence detection system. The experimental results are in agreement with Monte Carlo calculations and Schiffs theory. RP WIELOPOLSKI, L (reprint author), BROOKHAVEN NATL LAB,RTF BLDG 490,UPTON,NY 11973, USA. NR 17 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0094-2405 J9 MED PHYS JI Med. Phys. PD NOV-DEC PY 1992 VL 19 IS 6 BP 1435 EP 1439 DI 10.1118/1.596798 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA JY761 UT WOS:A1992JY76100011 PM 1461206 ER PT J AU NIROOMANDRAD, A HALEEM, M RODGERS, J OBCEMEA, C AF NIROOMANDRAD, A HALEEM, M RODGERS, J OBCEMEA, C TI WEDGE FACTOR DEPENDENCE ON DEPTH AND FIELD SIZE FOR VARIOUS BEAM ENERGIES USING SYMMETRICAL AND HALF-COLLIMATED ASYMMETRIC JAW SETTINGS SO MEDICAL PHYSICS LA English DT Article DE WEDGE FACTOR; RELATIVE WEDGE FACTOR; CO-60; 4-MV TO 18-MV X-RAY; PHOTON BEAMS ID X-RAYS; DOSIMETRY; 4-MV AB The depth- and field-size dependence of the in-phantom wedge factor have been determined for a Cobalt-60 (Co-60) teletherapy unit and four medical linear accelerators with 4-, 6-, 10-, and 18-MV x-ray beams containing 15-degrees-60-degrees (nominal) lead, brass, and steel wedge filters. Measurements were made with ionization chambers in solid water or water with a source-skin distance of 80 or 100 cm. Field sizes varied from 4 X 4 cm up to a maximum allowable size for each wedge filter. Measurements were performed for symmetric and half-collimated asymmetric fields at depth of maximum dose, 5- and 10-cm depths. For half-collimated fields, wedge factor reference points were located at a fixed off-axis distance from the collimator's rotational axis. These systematic measurements on wedges indicate that the wedge factor dependence on depth and field size is a function of beam energy as well as the design of the treatment head and wedge filters. Significance of the results reported herein are discussed for the most commonly used treatment depths and field sizes with various beam energies and wedge filters. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RP NIROOMANDRAD, A (reprint author), GEORGETOWN UNIV,MED CTR,DEPT RADIAT MED,WASHINGTON,DC 20007, USA. NR 11 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0094-2405 J9 MED PHYS JI Med. Phys. PD NOV-DEC PY 1992 VL 19 IS 6 BP 1445 EP 1450 DI 10.1118/1.596800 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA JY761 UT WOS:A1992JY76100013 PM 1461208 ER PT J AU PING, X MORRIS, JW AF PING, X MORRIS, JW TI COMPUTER-SIMULATION OF MICROSTRUCTURE DEVELOPMENT DURING A MARTENSITIC-TRANSFORMATION SO METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article AB The microstructure that results from a martensitic transformation is largely determined by the elastic strain that develops as martensite particles grow and interact. To study the development of microstructure, it is useful to have computer simulation models that mimic the process. One such model is a finite-element model in which the transforming body is divided into elementary cells that transform when it is energetically favorable to do so. Using the linear elastic theory, the elastic energy of an arbitrary distribution of transformed cells can be calculated, and the elastic strain field can be monitored as the transformation proceeds. In the present article, a model of this type is developed and evaluated by testing its ability to generate the preferred configurations of isolated martensite particles, which can be predicted analytically from the linear elastic theory. Both two- and three-dimensional versions of the model are used. The computer model is in good agreement with analytic theory when the latter predicts single-variant martensite particles. The three-dimensional model also generates twinned martensite in reasonable agreement with the analytic predictions when the fractions of the two variants in the particle are near 0.5. It is less successful in reproducing twinned martensites when one variant is dominant; however, in this case, it does produce unusual morphologies, such as "butterfly martensite," that have been observed experimentally. Neither the analytic theory nor the computer simulation predicts twinned martensites in the two-dimensional transformations considered here, revealing an inherent limitation of studies that are restricted to two dimensions. C1 UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720. RP PING, X (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720, USA. NR 13 TC 2 Z9 2 U1 0 U2 3 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0360-2133 J9 METALL TRANS A PD NOV PY 1992 VL 23 IS 11 BP 2999 EP 3012 PG 14 WC Materials Science, Multidisciplinary SC Materials Science GA JW151 UT WOS:A1992JW15100006 ER PT J AU WANG, HY NAJAFABADI, R SROLOVITZ, DJ LESAR, R AF WANG, HY NAJAFABADI, R SROLOVITZ, DJ LESAR, R TI SEGREGATION EFFECTS ON INTERGRANULAR FRACTURE - AN ATOMISTIC SIMULATION STUDY OF NI-CU ALLOYS SO METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID INTERFACES; ENERGY AB The effects of segregation on the cohesive energy or ideal fracture toughness of a SIGMA5 [001] twist boundary in Ni-Cu alloys have been examined for a wide range of temperatures and compositions within the solid solution region of the phase diagram. The cohesive energy 2 gamma(int) is defined as the difference between the free energies of the surfaces created and the grain boundary destroyed when a crack propagates along a grain boundary. Atomistic simulations of the SIGMA5 [001] twist boundary and (001) surfaces were performed within the framework of the free energy simulation method that is based upon minimizing an approximate free energy functional with respect to both atom positions and solute concentration profile. Three different types of cohesive energies (2 gamma(int))mu, (2 gamma(int))GAMMA, and (2 gamma(int))c have been evaluated; (2 gammma(int))mu, is the cohesive energy for slow fracture, (2 gamma(int))GAMMA is the cohesive energy for fast fracture, and (2 gammma(int))C is the cohesive energy of the unsegregated boundary. In the normal situation (where the solute segregates more strongly to the surface than the boundary), the inequality (2 gamma(int))mu less-than-or-equal-to (2 gamma(int))GAMMA less-than-or-equal-to (2 gamma(int))C is always satisfied, and for anomalous segregators (where the solute segregates more strongly to the boundary than the surface), (2 gamma(int))C less-than-or-equal-to (2 gamma(int)), less-than-or-equal-to (2 gamma(int))GAMMA is satisfied. For all Ni-Cu alloy bulk compositions (0.05 less-than-or-equal-to C less-than-or-equal-to 0.95) and temperatures (400 less-than-or-equal-to T(K) less-than-or-equal-to 1000) examined, Cu segregates strongly to both the grain boundary and the free surface. Nonetheless, segregation only results in a small reduction (10 pct) in 2 gamma(int) compared with the unsegregated case. The difference between the fast fracture (2 gamma(int)GAMMA and slow fracture (2 gamma(int))mu cohesive energies is very small. Therefore, at least in the Ni-Cu system, the two theoretical bounds on 2 gamma(int) are tight. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP WANG, HY (reprint author), UNIV MICHIGAN,DEPT MAT SCI & ENGN,ANN ARBOR,MI 48109, USA. RI LeSar, Richard/G-1609-2012 NR 16 TC 4 Z9 4 U1 1 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0360-2133 J9 METALL TRANS A PD NOV PY 1992 VL 23 IS 11 BP 3105 EP 3113 DI 10.1007/BF02646129 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA JW151 UT WOS:A1992JW15100017 ER PT J AU LEESMILLER, SP SAKAGUCHI, K ULLRICH, SJ APPELLA, E ANDERSON, CW AF LEESMILLER, SP SAKAGUCHI, K ULLRICH, SJ APPELLA, E ANDERSON, CW TI HUMAN DNA-ACTIVATED PROTEIN-KINASE PHOSPHORYLATES SERINE-15 AND SERINE-37 IN THE AMINO-TERMINAL TRANSACTIVATION DOMAIN OF HUMAN P53 SO MOLECULAR AND CELLULAR BIOLOGY LA English DT Article ID WILD-TYPE P53-PROTEIN; CELL-CYCLE CONTROL; RNA POLYMERASE-II; LARGE-T-ANTIGEN; 3T3 CELLS; SEQUENCE; BINDING; GENE; SUPPRESSION; INVITRO AB Human DNA-PK is a nuclear, serine/threonine protein kinase that, when activated by DNA, phosphorylates several DNA-binding substrates, including the tumor suppressor protein p53. To identify which p53 residues are phosphorylated, we examined DNA-PK's ability to phosphorylate synthetic peptides corresponding to human p53 sequences. Serines 15 and 37 in the amino-terminal transactivation domain of human p53, and serines 7 and 18 of mouse p53, were phosphorylated by DNA-PK in the context of synthetic peptides. Other serines in these p53 peptides, and serines in other p53 peptides, including peptides containing the serine 315 p34cdc2 site and the serine 392 casein kinase II site, were not recognized by DNA-PK or were phosphorylated less efficiently. Phosphorylation of the conserved serine 15 in human p53 peptides depended on the presence of an adjacent glutamine, and phosphorylation was inhibited by the presence of a nearby lysine. Phosphorylation of recombinant wild-type mouse p53 was inhibited at high DNA concentrations, suggesting that DNA-PK may phosphorylate p53 only when both are bound to DNA at nearby sites. Our study suggests that DNA-PK may have a role in regulating cell growth and indicates how phosphorylation of serine 15 in DNA-bound p53 could alter p53 function. C1 BROOKHAVEN NATL LAB, DEPT BIOL, UPTON, NY 11973 USA. NCI, CELL BIOL LAB, BETHESDA, MD 20892 USA. NR 59 TC 455 Z9 458 U1 0 U2 9 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0270-7306 EI 1098-5549 J9 MOL CELL BIOL JI Mol. Cell. Biol. PD NOV PY 1992 VL 12 IS 11 BP 5041 EP 5049 PG 9 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA JT845 UT WOS:A1992JT84500025 PM 1406679 ER PT J AU WILLIS, JO AF WILLIS, JO TI EXPERIENCES OF A FOREIGN RESEARCHER IN JAPAN SO MRS BULLETIN LA English DT Editorial Material RP WILLIS, JO (reprint author), LOS ALAMOS NATL LAB,CTR SUPERCONDUCT TECHNOL,LOS ALAMOS,NM 87544, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0883-7694 J9 MRS BULL JI MRS Bull. PD NOV PY 1992 VL 17 IS 11 BP 11 EP 11 PG 1 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA JY763 UT WOS:A1992JY76300002 ER PT J AU ALPER, M AF ALPER, M TI BIOLOGY AND MATERIALS .2. SO MRS BULLETIN LA English DT Editorial Material RP ALPER, M (reprint author), LAWRENCE BERKELEY LAB,ENZYMAT SYNTH PROGRAM,BERKELEY,CA 94720, USA. NR 0 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 0883-7694 J9 MRS BULL JI MRS Bull. PD NOV PY 1992 VL 17 IS 11 BP 36 EP 37 PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA JY763 UT WOS:A1992JY76300003 ER PT J AU ALPER, M AF ALPER, M TI THE BIOLOGICAL MEMBRANE SO MRS BULLETIN LA English DT Article RP ALPER, M (reprint author), LAWRENCE BERKELEY LAB,DIV MAT SCI,ENZYMAT SYNTH PROGRAM,BERKELEY,CA 94720, USA. NR 0 TC 15 Z9 15 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 NOV PY 1992 VL 17 IS 11 BP 53 EP 55 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA JY763 UT WOS:A1992JY76300007 ER PT J AU CHARYCH, DH BEDNARSKI, MD AF CHARYCH, DH BEDNARSKI, MD TI SELF-ASSEMBLED AND LANGMUIR-BLODGETT ORGANIC THIN-FILMS AS FUNCTIONAL MATERIALS SO MRS BULLETIN LA English DT Article ID CELL-ADHESION; HYDROXYL-GROUPS; ADSORBED FILMS; MONOLAYER FILM; SURFACES; GOLD; POLYMERIZATION; ELECTROCHEMISTRY; PHTHALOCYANINE; SPECTROSCOPY C1 LAWRENCE BERKELEY LAB,DEPT CHEM,BERKELEY,CA 94720. RP CHARYCH, DH (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720, USA. NR 61 TC 17 Z9 17 U1 1 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 NOV PY 1992 VL 17 IS 11 BP 61 EP 66 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA JY763 UT WOS:A1992JY76300009 ER PT J AU GARD, HA AF GARD, HA TI RESOURCE DISTRIBUTION AND PREHISTORIC UTILIZATION OF SOUTHERN OREGON COASTAL ISLANDS SO NORTHWEST SCIENCE LA English DT Article AB The portion of the Oregon coast extending from Cape Blanco south into California has long been recognized as a unique physiographic region, resulting in distinct prehistoric subsistence and settlement patterns when compared with other coastal areas. Several researchers have proposed models emphasizing littoral adaptive strategies for this region but have failed to outline the type, distribution, and abundance of subsistence resources available to prehistoric populations. I propose that the abundant offshore rocks and islands along this section of coast served to concentrate marine resources and were, therefore, of economic importance to prehistoric populations. In particular, I demonstrate that 1) rocky coastlines are highly productive environments providing a variable, abundant, year-round food supply of immediate use to humans; 2) this high productivity can be directly related to the increased habitat provided by offshore rocks and islands; and 3) these offshore resources were utilized by prehistoric peoples. A combination of archaeological testing of one offshore island site and a sample survey of selected rocks and islands provides evidence of prehistoric utilization of offshore features. A majority of settlement/subsistence models tend to use observed site distributions to infer a region's relative biotic productivity, an inaccurate approach. This paper illustrates an alternate approach by determining the resources provided by a rocky coastline, inferring human use of those resources, and collecting archaeological evidence of that use. RP GARD, HA (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU WASHINGTON STATE UNIV PI PULLMAN PA PO BOX 645910, PULLMAN, WA 99164-5910 SN 0029-344X J9 NORTHWEST SCI JI Northwest Sci. PD NOV PY 1992 VL 66 IS 4 BP 207 EP 217 PG 11 WC Ecology SC Environmental Sciences & Ecology GA JW776 UT WOS:A1992JW77600001 ER PT J AU GEE, GW FAYER, MJ ROCKHOLD, ML CAMPBELL, MD AF GEE, GW FAYER, MJ ROCKHOLD, ML CAMPBELL, MD TI VARIATIONS IN RECHARGE AT THE HANFORD SITE SO NORTHWEST SCIENCE LA English DT Article AB Recharge from meteoric sources (rain and snowmelt) is an important hydrologic variable. A knowledge of recharge rates is needed in the assessment of potential groundwater contamination problems at the U.S. Department of Energy's Hanford Site, near Richland, Washington. Lysimeter data, collected at a number of locations at Hanford over a period of 20 yrs, indicate that recharge rates vary widely, ranging from more than 100 mm/yr to rates near zero (i.e., no measurable drainage). This wide range in recharge is attributed to variations in precipitation, vegetative cover, and surface soil-type. Coarse-textured soils without plants yield the most recharge, fine-textured soils with or without plants yield the least. Deep-rooted plants, such as sagebrush, are generally successful in limiting recharge on all soils at Hanford to near-zero amounts, but shallow-rooted plants such as cheatgrass appear unable to prevent recharge. Drainage (i.e., recharge) from a cheatgrass-covered lysimeter, backfilled with sandy soil, averaged 62 mm/yr (35% of the annual precipitation) during a 3-yr test (1984 to 1986). The time required for contaminants to travel through the thick unsaturated zone at Hanford is estimated to range from thousands of years, for recharge rates below 1 mm/yr, to tens of years, for recharge rates above 50 mm/yr. The implications of these findings to environmental cleanup and management at Hanford are significant. Present practices that replace surface soils with coarse sands and gravels and prevent or limit vegetative growth are inducing significant recharge that may contribute to contaminant migration. Remediation, such as covering waste sites with a silt-loam soil layer, may be required to limit recharge to negligible amounts, thus ensuring long-term protection of groundwater. RP GEE, GW (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 0 TC 46 Z9 47 U1 2 U2 7 PU WASHINGTON STATE UNIV PI PULLMAN PA PO BOX 645910, PULLMAN, WA 99164-5910 SN 0029-344X J9 NORTHWEST SCI JI Northwest Sci. PD NOV PY 1992 VL 66 IS 4 BP 237 EP 250 PG 14 WC Ecology SC Environmental Sciences & Ecology GA JW776 UT WOS:A1992JW77600005 ER PT J AU WHIRLEY, RG ENGELMANN, BE AF WHIRLEY, RG ENGELMANN, BE TI RECENT DEVELOPMENTS IN DYNA3D FOR IMPACT PROBLEMS SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT POST-CONF SEMINAR ON IMPACT AND LARGE DEFORMATION MECHANICS OF THE 11TH INTERNATIONAL CONF ON STRUCTURAL MECHANICS IN REACTOR TECHNOLOGY CY AUG 26-27, 1991 CL TOKYO, JAPAN AB DYNA3D is an explicit, large deformation finite element code which is widely used for modeling complex impact problems. Recent research and development activities at LLNL have yielded a number of improvements to DYNA3D, including a new shell element, a new material model for concrete, sand, and rock, a new set of anisotropic plasticity models for both solid and shell elements, a material model driver with interactive graphics, and others. This paper opens with an overview of the current capabilities of DYNA3D. Next, some new results in the finite element formulation of elastoplastic shell problems are presented. Then, recent developments on a new, fully vectorized two-invariant extended cap model are described. Two large-scale example problems are then presented which illustrate the application of DYNA3D to production impact analysis. The paper closes with a brief discussion of future research and development directions. RP WHIRLEY, RG (reprint author), LAWRENCE LIVERMORE NATL LAB,METHODS DEV GRP,L-122,POB 808,LIVERMORE,CA 94550, USA. NR 18 TC 0 Z9 0 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 NOV PY 1992 VL 138 IS 1 BP 11 EP 22 DI 10.1016/0029-5493(92)90274-Y PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KC650 UT WOS:A1992KC65000002 ER PT J AU ENGELMANN, BE WHIRLEY, RG AF ENGELMANN, BE WHIRLEY, RG TI RECENT DEVELOPMENTS IN NIKE2D FOR METALFORMING ANALYSIS AND LOW RATE IMPACT SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT POST-CONF SEMINAR ON IMPACT AND LARGE DEFORMATION MECHANICS OF THE 11TH INTERNATIONAL CONF ON STRUCTURAL MECHANICS IN REACTOR TECHNOLOGY CY AUG 26-27, 1991 CL TOKYO, JAPAN ID ELASTOPLASTIC CONSTITUTIVE RELATIONS; INTEGRATION ALGORITHMS AB Analyses involving low rate impact and metalforming processes with large distortions require a robust, large deformation, finite element capability with good contact algorithms. The rapidly evolving NIKE codes are ideally suited for these types of problems. This paper highlights new metalforming simulation capabilities developed at Lawrence Livermore National Laboratory, including rezoning, adaptive time step and solution strategies, and new constutive models. Numerical examples illustrating the performance and application of NIKE2D are presented. RP ENGELMANN, BE (reprint author), LAWRENCE LIVERMORE NATL LAB,METHODS DEV GRP,L-122,POB 808,LIVERMORE,CA 94550, USA. NR 14 TC 0 Z9 0 U1 0 U2 0 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 NOV PY 1992 VL 138 IS 1 BP 23 EP 35 DI 10.1016/0029-5493(92)90275-Z PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KC650 UT WOS:A1992KC65000003 ER PT J AU TILL, CE CHANG, YI AF TILL, CE CHANG, YI TI INTEGRATING THE FUEL-CYCLE AT IFR SO NUCLEAR ENGINEERING INTERNATIONAL LA English DT Article RP TILL, CE (reprint author), ARGONNE NATL LAB,IFR PROGRAMME,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU REED BUSINESS PUBLISHING LTD PI SUTTON PA QUADRANT HOUSE THE QUADRANT, SUTTON, SURREY, ENGLAND SM2 5AS SN 0029-5507 J9 NUCL ENG INT JI Nucl. Eng. Int. PD NOV PY 1992 VL 38 IS 460 BP 33 EP 34 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KA790 UT WOS:A1992KA79000006 ER PT J AU WEINBERG, A AF WEINBERG, A TI REVISITING THE 2ND NUCLEAR ERA - PROBABILITIES AND PRACTICALITIES SO NUCLEAR ENGINEERING INTERNATIONAL LA English DT Editorial Material RP WEINBERG, A (reprint author), OAK RIDGE ASSOCIATED UNIV,OAK RIDGE,TN 37830, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU REED BUSINESS PUBLISHING LTD PI SUTTON PA QUADRANT HOUSE THE QUADRANT, SUTTON, SURREY, ENGLAND SM2 5AS SN 0029-5507 J9 NUCL ENG INT JI Nucl. Eng. Int. PD NOV PY 1992 VL 38 IS 460 BP 36 EP 36 PG 1 WC Nuclear Science & Technology SC Nuclear Science & Technology GA KA790 UT WOS:A1992KA79000007 ER PT J AU HOULBERG, WA ATTENBERGER, SE BAYLOR, LR GADEBERG, M JERNIGAN, TC KUPSCHUS, P MILORA, SL SCHMIDT, GL SWAIN, DW WATKINS, ML AF HOULBERG, WA ATTENBERGER, SE BAYLOR, LR GADEBERG, M JERNIGAN, TC KUPSCHUS, P MILORA, SL SCHMIDT, GL SWAIN, DW WATKINS, ML TI PELLET PENETRATION EXPERIMENTS ON JET SO NUCLEAR FUSION LA English DT Article ID TEXAS EXPERIMENTAL TOKAMAK; HYDROGEN PELLET; SHIELDING MODEL; ABLATION; PLASMA; DISCHARGES; INJECTION; TRANSPORT AB The measured penetration depth lambda of deuterium pellets injected into the Joint European Torus (JET) confirms some features of the neutral gas shielding (NGS) model, but not others. The scaling of lambda with plasma and pellet parameters agrees with the NGS model, as in earlier ASDEX studies. Pellet velocity was varied over the range 0.46-1.35 km/s in the JET experiments to test specifically the scaling of lambda with velocity. This scaling also agrees with the NGS model. However, the penetration is deeper in JET than in ASDEX when it is corrected for the expected machine size dependence. Furthermore, the penetration depths measured in JET are greater (by nearly a factor of two) than those predicted by local ablation calculations using the NGS model with an incident Maxwellian distribution of electrons. Plasma shielding used in previous modelling of the JET penetration data can account for the additional shielding, but it also removes the observed velocity dependence. The implications of both the scaling observations and the penetration depths for improvements in ablation theory and in the models are discussed. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. PRINCETON UNIV,PLASMA PHYS LAB,PRINCETON,NJ 08544. RP HOULBERG, WA (reprint author), JET JOINT UNDERTAKING,ABINGDON,OXON,ENGLAND. NR 31 TC 18 Z9 18 U1 1 U2 5 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 NOV PY 1992 VL 32 IS 11 BP 1951 EP 1965 DI 10.1088/0029-5515/32/11/I07 PG 15 WC Physics, Fluids & Plasmas SC Physics GA KA558 UT WOS:A1992KA55800007 ER PT J AU HILL, DN AF HILL, DN TI CREATING AN INTERNATIONAL EDGE PHYSICS DATABASE - REPORT ON THE WORKSHOP HELD AT THE 10TH PSI CONFERENCE, MONTEREY, CALIFORNIA, UNITED-STATES-OF-AMERICA, 30 MARCH - 3 APRIL 1992 SO NUCLEAR FUSION LA English DT Editorial Material RP HILL, DN (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD NOV PY 1992 VL 32 IS 11 BP 2053 EP 2053 DI 10.1088/0029-5515/32/11/419 PG 1 WC Physics, Fluids & Plasmas SC Physics GA KA558 UT WOS:A1992KA55800019 ER PT J AU MCGRATH, RT KELLMAN, AG AF MCGRATH, RT KELLMAN, AG TI TECHNOLOGY AND PLASMA-MATERIALS INTERACTION PROCESSES OF TOKAMAK DISRUPTIONS - REPORT ON THE WORKSHOP HELD AT THE 10TH PSI CONFERENCE, MONTEREY, CALIFORNIA, UNITED-STATES-OF-AMERICA, 3 APRIL 1992 SO NUCLEAR FUSION LA English DT Editorial Material C1 GEN ATOM CO,SAN DIEGO,CA 92138. RP MCGRATH, RT (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 4 TC 1 Z9 1 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 NOV PY 1992 VL 32 IS 11 BP 2054 EP 2055 DI 10.1088/0029-5515/32/11/420 PG 2 WC Physics, Fluids & Plasmas SC Physics GA KA558 UT WOS:A1992KA55800020 ER PT J AU HOGAN, JT HILLIS, DL AF HOGAN, JT HILLIS, DL TI HELIUM TRANSPORT AND EXHAUST IN TOKAMAK EXPERIMENTS - REPORT ON THE WORKSHOP HELD AT THE 10TH PSI CONFERENCE, MONTEREY, CALIFORNIA, UNITED-STATES-OF-AMERICA, 1 APRIL 1992 SO NUCLEAR FUSION LA English DT Editorial Material RP HOGAN, JT (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 0 TC 2 Z9 2 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 NOV PY 1992 VL 32 IS 11 BP 2055 EP 2056 DI 10.1088/0029-5515/32/11/421 PG 2 WC Physics, Fluids & Plasmas SC Physics GA KA558 UT WOS:A1992KA55800021 ER PT J AU CAUSEY, RA AF CAUSEY, RA TI TRITIUM IN PLASMA FACING COMPONENTS - REPORT ON THE WORKSHOP HELD AFTER THE 10TH PSI CONFERENCE, LIVERMORE, CALIFORNIA, UNITED-STATES-OF-AMERICA, 6-7 APRIL 1992 SO NUCLEAR FUSION LA English DT Editorial Material RP CAUSEY, RA (reprint author), SANDIA NATL LABS,DIV FUS RES,LIVERMORE,CA 94550, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD NOV PY 1992 VL 32 IS 11 BP 2056 EP 2057 DI 10.1088/0029-5515/32/11/422 PG 2 WC Physics, Fluids & Plasmas SC Physics GA KA558 UT WOS:A1992KA55800022 ER PT J AU HILL, DN AF HILL, DN TI SCRAPE-OFF LAYER BIASING, CURRENTS, AND ELECTRIC-FIELD EFFECTS IN TOKAMAKS - REPORT ON THE WORKSHOP HELD AFTER THE 10TH PSI CONFERENCE, BORREGO SPRINGS, CALIFORNIA, UNITED-STATES-OF-AMERICA, 6-8 APRIL 1992 SO NUCLEAR FUSION LA English DT Editorial Material RP HILL, DN (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD NOV PY 1992 VL 32 IS 11 BP 2057 EP 2058 DI 10.1088/0029-5515/32/11/423 PG 2 WC Physics, Fluids & Plasmas SC Physics GA KA558 UT WOS:A1992KA55800023 ER PT J AU BERTUCCIO, G GATTI, E SAMPIETRO, M REHAK, P RESCIA, S AF BERTUCCIO, G GATTI, E SAMPIETRO, M REHAK, P RESCIA, S TI SAMPLING AND OPTIMUM DATA-PROCESSING OF DETECTOR SIGNALS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID SILICON DRIFT CHAMBERS; NOISE AB The optimum processing of data, obtained by sampling detector signals, is developed for signals known a priori in shape, their time of occurrence and amplitude being unknown. The processing is based on the maximum-likelihood method. The resolutions in the time and amplitude estimations of the pulse are compared with those obtained from an optimum analog filter. Results are presented for a fixed number of samples points at different sampling rates. It is shown that undersampling does not introduce systematic errors because of the pulse shape known a priori but only decreases the resolution and makes it somewhat sensitive to the position of the pulse in relation to the sampling comb. The paper gives the criteria needed for reconstructing the weighting function for digital processors, stressing the links between conventional analog processing and sampled data processing. This makes it possible to choose the best compromise between achievable resolution and computational requirements. C1 POLITECN MILAN,CNR,CTR ELETTRON QUANTIST & STRUMENTAZ ELETTRON,I-20133 MILAN,ITALY. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP BERTUCCIO, G (reprint author), POLITECN MILAN,DIPARTIMENTO ELETTRON,P ZA LEONARDO DA VINCI 32,I-20133 MILAN,ITALY. RI Rescia, Sergio/D-8604-2011; Sampietro, Marco/A-3732-2016 OI Rescia, Sergio/0000-0003-2411-8903; Sampietro, Marco/0000-0003-4825-9612 NR 11 TC 25 Z9 25 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 NOV 1 PY 1992 VL 322 IS 2 BP 271 EP 279 DI 10.1016/0168-9002(92)90040-B PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA JX799 UT WOS:A1992JX79900020 ER PT J AU HARADA, H TAKAHASHI, H KONASHI, K SASAO, N AF HARADA, H TAKAHASHI, H KONASHI, K SASAO, N TI INCINERATION OF SR-90 AND CS-137 BY AN INERTIAL FUSION TARGET SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID THERMONUCLEAR AB We discuss the inertial confinement fusion system as a transmutator of radioactive waste (Sr-90 and Cs-137). An analytic model of the implosion of the target, which is composed of DT fuel and radioactive waste, is used to evaluate its internal energy and the probability of neutron utilization. From the results of this calculation, we could evaluate the energy that is required to transmute radioactive waste. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RP HARADA, H (reprint author), POWER REACTOR & NUCL FUEL DEV CORP,TOKAI,IBARAKI 31911,JAPAN. RI konashi, kenji/P-6215-2014 NR 24 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD NOV 1 PY 1992 VL 322 IS 2 BP 286 EP 292 DI 10.1016/0168-9002(92)90042-3 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA JX799 UT WOS:A1992JX79900022 ER PT J AU FUNSTEN, HO AF FUNSTEN, HO TI MODEL FOR BEAM-INDUCED DEPOSITION OF THIN METALLIC-FILMS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID FOCUSED ION-BEAMS; SCANNING TUNNELING MICROSCOPE; SELECTIVE AREA DEPOSITION; ENERGY ELECTRON-BEAMS; RAY MASK REPAIR; STIMULATED DEPOSITION; ASSISTED DEPOSITION; GOLD; TECHNOLOGY; FEATURES AB Recent advances in focused ion beam (FIB) technology have expanded the applications of beam-induced deposition (BID) of thin metallic films in microcircuit fabrication. This paper provides a model for the BID process by examining the effects on film growth and morphology of various deposition parameters including the incident ion flux, adsorbate coverage of the substrate and residue, residue sputtering, and energy deposition by incident ions. Residue nucleation is examined, and a significant difference between adsorbate coverage of the substrate and residue is found to introduce large thickness variations in the film. Adsorbate depletion which is caused by an increase in the ion beam current density or target temperature results in a larger energy deposition per residue molecule and is proposed as a mechanism for enhancement of the metallic purity and electrical conductivity of the residue. By investigating the film growth rate during periodic ion bombardment characteristic of focused ion beams, the model demonstrates that the maximum film growth rate is obtained by maximizing the scanning frequency. The model is found to quantitatively agree with published experimental results. RP FUNSTEN, HO (reprint author), LOS ALAMOS NATL LAB,MS DE38,LOS ALAMOS,NM 87545, USA. RI Funsten, Herbert/A-5702-2015 OI Funsten, Herbert/0000-0002-6817-1039 NR 33 TC 8 Z9 8 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD NOV PY 1992 VL 72 IS 2 BP 183 EP 196 DI 10.1016/0168-583X(92)95233-H PG 14 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA JZ638 UT WOS:A1992JZ63800006 ER PT J AU WONG, KL BEIERSDORFER, P MARRS, RE PENETRANTE, BM REED, KJ SCOFIELD, JH VOGEL, DA ZASADZINSKI, R AF WONG, KL BEIERSDORFER, P MARRS, RE PENETRANTE, BM REED, KJ SCOFIELD, JH VOGEL, DA ZASADZINSKI, R TI X-RAY-MEASUREMENT OF THE IONIZATION BALANCE IN AN ELECTRON-BEAM ION TRAP SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID HIGHLY CHARGED IONS; CROSS-SECTIONS; ENERGY; TRANSITION; EXCITATION; SPECTRA; BARIUM AB The charge-state abundances of bare, hydrogen-, helium-, lithium-, and beryllium-like iron in the Livermore electron beam ion trap have been measured with uncertainties ranging from 3 to 15% by monitoring the emitted X rays. The ionization balance is determined in two ways: (1) by observing radiative recombination photons with a solid-state detector, and (2) by observing line radiation with a Bragg crystal spectrometer. The results are in good agreement with an ionization balance model. RP WONG, KL (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV HIGH TEMP PHYS,POB 808,L-421,LIVERMORE,CA 94550, USA. NR 26 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD NOV PY 1992 VL 72 IS 2 BP 234 EP 238 DI 10.1016/0168-583X(92)95239-N PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA JZ638 UT WOS:A1992JZ63800012 ER PT J AU MEAD, WC BOWLING, PS BROWN, SK JONES, RD BARNES, CW GIBSON, HE GOULDING, JR LEE, YC AF MEAD, WC BOWLING, PS BROWN, SK JONES, RD BARNES, CW GIBSON, HE GOULDING, JR LEE, YC TI OPTIMIZATION AND CONTROL OF A SMALL-ANGLE NEGATIVE-ION SOURCE USING AN ONLINE ADAPTIVE CONTROLLER BASED ON THE CONNECTIONIST NORMALIZED LOCAL SPLINE NEURAL NETWORK SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article AB We have developed CTL, an on-line adaptive controller, to optimize and control a repetitively pulsed, small-angle negative ion source. CTL processes multiple diagnostics to determine the ion source operating conditions. A figure of merit is constructed that weights beam current magnitude, noise, and pulse-to-pulse repeatability. The operating space of the ion source is mapped coarsely using automated scan procedures. Then CTL, using information derived by fitting the sparse operating-space data with the Connectionist Normalized Local Spline artificial neural network, interactively adjusts four ion-source control knobs (through regulating control loops) to optimize the figure of merit. Fine tuning is performed by executing a modified gradient search algorithm directly on the machine. Resulting beam quality is consistently quite good. CTL has tuned the ion source for nearly optimum operation on six cold startups in one to four hours from the time of initial arc. After a brief interruption of operation, return to optimized beam performance typically takes only about fifteen minutes. C1 LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,DIV ACCELERATOR TECHNOL,LOS ALAMOS,NM 87545. UNIV MARYLAND,DEPT PHYS & ASTRON,COLL PK,MD 20740. RP MEAD, WC (reprint author), LOS ALAMOS NATL LAB,DIV APPL THEORET PHYS,LOS ALAMOS,NM 87545, USA. NR 19 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD NOV PY 1992 VL 72 IS 2 BP 271 EP 289 DI 10.1016/0168-583X(92)95243-K PG 19 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA JZ638 UT WOS:A1992JZ63800016 ER PT J AU DIAS, AF EISENHART, LD BELL, DM GARRETT, TJ NEISES, GJ AGEE, LJ AF DIAS, AF EISENHART, LD BELL, DM GARRETT, TJ NEISES, GJ AGEE, LJ TI IMPROVED PRESSURIZED WATER-REACTOR STEAMLINE BREAK ANALYSIS USING RETRAN-02, ARROTTA, AND VIPRE-02 SO NUCLEAR TECHNOLOGY LA English DT Article DE STEAMLINE BREAK ANALYSIS; 3-DIMENSIONAL SIMULATION; ARROTTA-01/VIPRE-02/RETRAN-02 AB The steamline break accident is one of several specified severe transients addressed in the final safety analysis report for any pressurized water reactor plant as part of the licensing procedure. A rupture in a main steamline in the secondary system causes a sudden cooling of the water in the corresponding primary loop. The cold water flo wing in to part of the core represents a positive reactivity insertion that must be contained by control rods, which are scrammed into the core almost immediately. Later in the scenario, soluble boron reaches the core from the emergency core cooling system. When simulating a steamline break accident during the licensing procedure, many conservative assumptions are added to the transient description. Historically, a steamline break analysis is performed with a system analysis code like RETRAN, using a rather simplified (point kinetics) description of the core. The three-dimensionality of the event within the core is accounted for by constant "blending factors, " which are used to calculate the evolving point kinetics parameters based on a simplistic cold and hot partition of the core. The ARROTTA-01 and VIPRE-02 computer codes are coupled to allow a detailed three-dimensional simulation of the reactor core during a steamline break event. The results show that a much milder transient is observed than when a point kinetics treatment was used. Test cases study the influence of different core modeling considerations on the overall simulation. The advent of very fast and extremely affordable computing machines (e.g., workstations) should cause the review of some of the simplified approaches initially adopted for many core simulations. More complex and detailed codes can now be routinely employed. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. WOLF CREEK NUCL OPERATING CORP, DIV NUCL SAFETY ANAL, WICHITA, KS 67201 USA. ELECT POWER RES INST, PALO ALTO, CA 94303 USA. RP DIAS, AF (reprint author), S LEVY INC, 3425 S BASCOM AVE, CAMPBELL, CA 95008 USA. NR 6 TC 6 Z9 6 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD NOV PY 1992 VL 100 IS 2 BP 193 EP 202 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA JV738 UT WOS:A1992JV73800006 ER PT J AU KELLY, JM STEWART, CW CUTA, JM AF KELLY, JM STEWART, CW CUTA, JM TI VIPRE-02 - A 2-FLUID THERMAL-HYDRAULICS CODE FOR REACTOR CORE AND VESSEL ANALYSIS - MATHEMATICAL-MODELING AND SOLUTION METHODS SO NUCLEAR TECHNOLOGY LA English DT Article DE THERMAL-HYDRAULICS CODE; 2-FLUID MODEL; 2-PHASE FLOW COMPUTATION AB The VIPRE-02 code is a thermal-hydraulic analysis code designed to model steady-state conditions and operational transients in light water reactor cores and vessels. It uses a two-fluid representation of two-phase flow that solves conservation equations for mass, momentum, and energy for each phase. The code uses a subchannel formulation of the conservation equations but also contains an optional three-dimensional (r-theta coordinates) representation of the lower plenum for vessel modeling. The six-equation formulation is solved implicitly, by a modified Gauss-Seidel iteration procedure, and has no time step size limitation for stability. Models for phase interaction based on flow regime mapping are provided that use empirical models and correlations for heat and mass transfer at the interface and vapor generation. In addition, the code contains as an option a dynamic flow regime model, which uses an interfacial area transport equation to determine the phase interaction terms. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. MIT, CAMBRIDGE, MA 02139 USA. NR 10 TC 8 Z9 8 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD NOV PY 1992 VL 100 IS 2 BP 246 EP 259 PG 14 WC Nuclear Science & Technology SC Nuclear Science & Technology GA JV738 UT WOS:A1992JV73800010 ER PT J AU GOLUB, I AF GOLUB, I TI BEAM DEFLECTION AND ULTRAFAST ANGULAR SCANNING BY A TIME-VARYING OPTICALLY INDUCED PRISM SO OPTICS COMMUNICATIONS LA English DT Article ID NONLINEAR MEDIUM; SELF-DEFLECTION; SODIUM VAPOR; LASER-BEAM; MODULATION; CS2 AB By using dispersionless nonlinear refraction in CS2, a weak 0.53 mum beam is deflected by up to 3 mrad by an intense, copropagating, 1.06 mum pump beam with an asymmetric transverse intensity profile. With a 100 ps pump pulse, the inferred scan rate of the visible beam is almost-equal-to 10(8) rad/s, corresponding to almost-equal-to 10(11) defl. spots/s. Such ultrafast angular deflection may be applied to the generation of ultrashort optical pulses. RP GOLUB, I (reprint author), LOS ALAMOS NATL LAB,DIV CHEM & LASER SCI,MS E543,LOS ALAMOS,NM 87545, USA. NR 25 TC 12 Z9 12 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 NOV 1 PY 1992 VL 94 IS 1-3 BP 143 EP 146 DI 10.1016/0030-4018(92)90423-O PG 4 WC Optics SC Optics GA JT748 UT WOS:A1992JT74800029 ER PT J AU NILSEN, J PORTER, JL DASILVA, LB MACGOWAN, BJ AF NILSEN, J PORTER, JL DASILVA, LB MACGOWAN, BJ TI 17-NM RUBIDIUM-ION LASER SO OPTICS LETTERS LA English DT Article ID X-RAY AMPLIFICATION AB We demonstrate a rubidium-ion laser with two strong laser lines at 17.3 and 17.6 nm. The lasing transitions are 3p --> 3s transitions in Ne-like rubidium. Gains of 1.9 and 1.4 cm-1 are measured for these two lines, respectively. This weak gain, as compared with that in other Ne-like laser systems, is ascribed to both the surface roughness of the target and the dilution associated with using rubidium chloride salt. In addition, three weaker lasing transitions are observed, including the anomalous J = 0 --> 1 transition at 16.5 nm. C1 LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RP NILSEN, J (reprint author), LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. NR 9 TC 4 Z9 4 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 EI 1539-4794 J9 OPT LETT JI Opt. Lett. PD NOV 1 PY 1992 VL 17 IS 21 BP 1518 EP 1520 DI 10.1364/OL.17.001518 PG 3 WC Optics SC Optics GA JU968 UT WOS:A1992JU96800012 PM 19798233 ER PT J AU ANDERSON, KB WINANS, RE BOTTO, RE AF ANDERSON, KB WINANS, RE BOTTO, RE TI THE NATURE AND FATE OF NATURAL RESINS IN THE GEOSPHERE .2. IDENTIFICATION, CLASSIFICATION AND NOMENCLATURE OF RESINITES SO ORGANIC GEOCHEMISTRY LA English DT Article DE RESINITE; AMBER; CLASSIFICATION; PYROLYSIS; PY-GC-MS; NMR; MATURATION ID MAGNETIC-RESONANCE SPECTROSCOPY; EXTANT DAMMAR RESINS; WASATCH PLATEAU COAL; CHEMICAL-COMPOSITION; FOSSIL RESINS; MASS-SPECTROMETRY; NMR-SPECTROSCOPY; BALTIC AMBER; C-13 NMR; PYROLYSIS AB A classification scheme for resinites is proposed. Most resinites may be classified, on the basis of structural characteristics, into one of four classes. In order to exclude the effects of structural changes which reflect differences in the relative maturity of different samples, classifications are based on the structural character of the original resin from which the resinite was derived. In all samples characterized to date, this may be reasonably inferred from analytical data concerning the structure and composition of the individual sample. Class I resinites, which are by far the most abundant form of resinite in the geosphere, are derived from resins based primarily on polymers of labdatriene (diterpenoid) carboxylic acids, especially communic or ozic acids. Class II resinites are derived from resins based on polymers of sesquiterpenoid hydrocarbons, especially various isomers of cadinene. Class III resinites are natural polystyrenes. Class IV resinites are the least well characterized of the four resinite classes defined, but appear to be largely non-polymeric materials, dominated by sesquiterpenoids based on the cedrane carbon skeleton. Resinites belonging to Class I are further subdivided into three sub-classes on the basis of details of their composition. Class Ia resinites, which include succinite and related "Baltic ambers", are derived from resins based primarily on communic acid and incorporate significant amounts of succinic acid into their macromolecular structure. Class Ib resinites are also derived from resins based primarily on communic acid, but do not contain succinic acid. Class Ic resinites are derived from resins based primarily on labdatrienoic acids of the enantio series, especially ozic and/or zanzibaric acids. The structure, origin, and identification of resinites of each class are discussed. The effects of maturation on the structure of Class I resinites, and the consequences of these changes for the recognition and classification of this form of resinite are also briefly discussed. C1 ARGONNE NATL LAB, DIV CHEM, ARGONNE, IL 60439 USA. NR 65 TC 124 Z9 127 U1 0 U2 18 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0146-6380 J9 ORG GEOCHEM JI Org. Geochem. PD NOV PY 1992 VL 18 IS 6 BP 829 EP 841 DI 10.1016/0146-6380(92)90051-X PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JW951 UT WOS:A1992JW95100007 ER PT J AU BURRELL, AK BRYAN, JC AF BURRELL, AK BRYAN, JC TI (MU-1-CP)TC(NAR)3 - SYNTHESIS AND STRUCTURE SO ORGANOMETALLICS LA English DT Note ID MAIN-GROUP ELEMENTS; RAY CRYSTAL-STRUCTURES; R = ME; TRANSITION-METALS; MULTIPLE BONDS; FLUXIONAL BEHAVIOR; MOLECULAR-STRUCTURE; COMPLEXES; EXAMPLE; REACTIVITY AB The reaction of KCp with Tcl(NAr)3 (Ar = 2,6-diisopropylphenyl) rapidlY forms (eta1-Cp)Tc(NAr)3. A single-crystal X-ray determination confirmed the eta1 nature of the cyclopentadienyl ligand. When Tcl(NAr)3 is treated with an excess of KCp, a second cyclopentadienyl group is added to the metal, giving K[Cp2Tc(NAr)3]. C1 LOS ALAMOS NATL LAB,INORGAN & STRUCT CHEM GRP INC-1,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,NUCL & RADIOCHEM GRP INC-15,LOS ALAMOS,NM 87545. NR 33 TC 23 Z9 23 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD NOV PY 1992 VL 11 IS 11 BP 3501 EP 3503 DI 10.1021/om00059a008 PG 3 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA JY625 UT WOS:A1992JY62500008 ER PT J AU EASTMAN, JA FITZSIMMONS, MR THOMPSON, LJ AF EASTMAN, JA FITZSIMMONS, MR THOMPSON, LJ TI THE THERMAL-PROPERTIES OF NANOCRYSTALLINE PD FROM 16-K TO 300-K SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID X-RAY-DIFFRACTION; SIZED CRYSTALLINE MATERIALS; GAS EVAPORATION TECHNIQUE; GRAIN-BOUNDARIES; SMALL PARTICLES; ELASTIC-CONSTANTS; SURFACE STRESS; PALLADIUM; GOLD; PARAMETER AB Quantitative X-ray diffraction measurements made over a temperature range 16-300 K on a Pd sample of 8-3 nm median grain size were compared with data acquired from a coarse-grained Pd reference sample. The larger Debye-Waller parameter of nanocrystalline Pd was found to be due to increased static displacements of atoms from their equilibrium sites compared with the static displacements in coarse-grained material. Consistent with this behaviour, the strain distribution determined from the width of intensity peaks was significantly broader in the nanocrystalline sample than in the coarse-grained sample. No grain-size-correlated differences in either thermal vibrational amplitude or lattice parameter were observed. In contradiction to previous reports of greatly increased thermal expansion coefficients in nanocrystalline metals, the change in lattice parameter of Pd from 16 to 300 K was observed to be independent of grain size. The results indicate that some regions of the nanocrystalline sample are in a state of compressive stress, while other regions are under a tensile stress. Comparisons with results for unconsolidated nanometre-sized powders indicate that the origin of the increased static displacements in nanocrystalline Pd may be due to the ultrafine powder production or subsequent consolidation processes, rather than being an inherent feature associated with a particular grain size. C1 LOS ALAMOS NATL LAB,LANSCE,LOS ALAMOS,NM 87544. RP EASTMAN, JA (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Eastman, Jeffrey/E-4380-2011; Lujan Center, LANL/G-4896-2012; OI Eastman, Jeff/0000-0002-0847-4265 NR 54 TC 115 Z9 115 U1 0 U2 7 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 NOV PY 1992 VL 66 IS 5 BP 667 EP 696 DI 10.1080/13642819208207667 PG 30 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA JX364 UT WOS:A1992JX36400007 ER PT J AU MENON, ESK KRISHNAN, KM AF MENON, ESK KRISHNAN, KM TI CHARGE-TRANSFER AND SHORT-RANGE ORDER IN CU-PD AND NI-MO ALLOYS SO PHILOSOPHICAL MAGAZINE LETTERS LA English DT Article AB Water-quenched samples of Cu-Pd and Ni-Mo alloys have been studied by electron diffraction and electron-energy-loss spectroscopy. Diffraction patterns from these alloys exhibit pronounced diffuse scattering due to short-range order. Determination of the white-line intensity in the energy-loss spectra from these samples indicated a concentration dependence and the results are discussed in terms of charge transfer associated with short-range order. C1 LAWRENCE BERKELEY LAB, NATL CTR ELECTRON MICROSCOPY, BERKELEY, CA 94720 USA. RP SYSTRAN CORP, 4126 LINDEN AVE, DAYTON, OH 45432 USA. NR 8 TC 13 Z9 13 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 0950-0839 EI 1362-3036 J9 PHIL MAG LETT JI Philos. Mag. Lett. PD NOV PY 1992 VL 66 IS 5 BP 271 EP 275 DI 10.1080/09500839208219044 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA JX366 UT WOS:A1992JX36600008 ER PT J AU JENSEN, JR NARUMALANI, S WEATHERBEE, O MORRIS, KS MACKEY, HE AF JENSEN, JR NARUMALANI, S WEATHERBEE, O MORRIS, KS MACKEY, HE TI PREDICTIVE MODELING OF CATTAIL AND WATERLILY DISTRIBUTION IN A SOUTH-CAROLINA RESERVOIR USING GIS SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID MSS DATA; MACROPHYTES; LAKES; TEMPERATURE; PLANTS AB Par Pond and L Lake are cooling reservoirs located on the Savannah River Site in South Carolina. Large beds of aquatic macrophytes (primarily cattail and waterlilies) exist in Par Pond and are now beginning to develop in L Lake. Biophysical knowledge about Par Pond was used to develop "environmental constraint criteria" to predict the future spatial distribution of aquatic macrophytes in L Lake. The L Lake biophysical data were placed in a 5- by 5-m raster geographic information system (GIS) and analyzed using Boolean logic. Areas in L Lake which were less-than-or-equal-to 4 m in depth, less-than-or-equal-to 10 percent slope, had a fetch of less-than-or-equal-to 500 m, were on suitable soil, and had water temperatures less-than-or-equal-to 33-degrees-C were identified. The final GIS model isolated 26.94 ha that meet all five environmental constraint criteria and are thus suitable aquatic macrophyte habitat (8.76 ha are suitable for cattails, 18.18 ha for waterlilies). Information on the future spatial distribution of aquatic macrophytes in L Lake is valuable when developing lake management plans. C1 WESTINGHOUSE SAVANNAH RIVER CO,SAVANNAH RIVER LAB,AIKEN,SC 29802. RP JENSEN, JR (reprint author), UNIV S CAROLINA,DEPT GEOG,COLUMBIA,SC 29208, USA. NR 50 TC 24 Z9 24 U1 2 U2 6 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 SN 0099-1112 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD NOV PY 1992 VL 58 IS 11 BP 1561 EP 1568 PG 8 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA JV672 UT WOS:A1992JV67200002 ER PT J AU PENNYCOOK, SJ CHISHOLM, MF JESSON, DE FEENSTRA, R ZHU, S ZHENG, XY LOWNDES, DJ AF PENNYCOOK, SJ CHISHOLM, MF JESSON, DE FEENSTRA, R ZHU, S ZHENG, XY LOWNDES, DJ TI GROWTH AND RELAXATION MECHANISMS OF YBA2CU3O7-X FILMS SO PHYSICA C LA English DT Article ID SCANNING TUNNELING MICROSCOPY; YBA2CU3O7-X/PRBA2CU3O7-X SUPERLATTICES; CRITICAL CURRENTS; THIN-FILMS; MICROSTRUCTURE AB Using a combination of Z-contrast scanning transmission electron microscopy, scanning tunneling microscopy, and plan view diffraction contrast imaging, we have studied the growth and relaxation mechanisms of YBa2Cu3O7-x deposited on MgO and SrTiO3 substrates. Two-dimensional island growth occurs on SrTiO3 substrates, with relaxation through the nucleation of dislocation half-loops. The threading dislocation segments then have a screw component and can lead to kinetic roughening through the development of growth pyramids. In contrast, growth on MgO occurs by true three-dimensional island growth (with no wetting layer), most of the interface being incommensurate with the substrate (although crystallographically aligned). Dislocations with both edge and screw components are generated on island coalescence. A highly anisotropic surface energy is shown to be responsible for cell-by-cell c perpendicular-to growth being thermodynamically preferred, although at high supersaturations a transition to a perpendicular-to growth occurs. C1 HLTH & SAFETY RES DIV,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. RP PENNYCOOK, SJ (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831, USA. OI Jesson, David/0000-0003-0897-1445 NR 21 TC 163 Z9 163 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV 1 PY 1992 VL 202 IS 1-2 BP 1 EP 11 DI 10.1016/0921-4534(92)90288-N PG 11 WC Physics, Applied SC Physics GA JW985 UT WOS:A1992JW98500001 ER PT J AU ZHANG, JP GROENKE, DA ZHANG, H DELOACH, DI DABROWSKI, B POEPPELMEIER, KR DRAVID, VP MARKS, LD AF ZHANG, JP GROENKE, DA ZHANG, H DELOACH, DI DABROWSKI, B POEPPELMEIER, KR DRAVID, VP MARKS, LD TI LOCAL-STRUCTURE OF Y1-XCAXSR2CU2GAO7 SUPERCONDUCTORS SO PHYSICA C LA English DT Article ID RESOLUTION ELECTRON-MICROSCOPY; O COMPOUND SYSTEM; CUPRATE SUPERCONDUCTORS; YBA2CU3O7-DELTA; DOMAINS AB The variation in the average and local structure of the superconductor family Y1-xCaxSr2Cu2GaO7 as calcium is substituted for yttrium (x=0.20, 0.35, and 0.40) is presented and discussed. Electron microscopy and X-ray diffraction were the primary techniques employed. The local structure found by the use of electron microscopy and X-ray diffraction agrees with that previously derived from single crystal X-ray and neutron diffraction. The gallate can be confused with the three layer perovskite structure of YBCO (Yba2cu3o7) because of the similarity of [011]Ga almost-equal-to [100]YBCO and [010]Ga almost-equal-to [110] YBCO zones. However, the composition of all crystals examined were homogeneous on a 10-100 nm scale. It was also found that the twin structure varied as a function of the calcium content. C1 NORTHWESTERN UNIV,DEPT MAT SCI & ENGN,EVANSTON,IL 60208. NORTHWESTERN UNIV,DEPT CHEM,EVANSTON,IL 60208. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. NO ILLINOIS UNIV,DE KALB,IL 60115. RP ZHANG, JP (reprint author), NORTHWESTERN UNIV,CTR SCI & TECHNOL,EVANSTON,IL 60208, USA. RI Marks, Laurence/B-7527-2009 NR 20 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV 1 PY 1992 VL 202 IS 1-2 BP 51 EP 60 DI 10.1016/0921-4534(92)90295-N PG 10 WC Physics, Applied SC Physics GA JW985 UT WOS:A1992JW98500008 ER PT J AU HOLESINGER, TG MILLER, DJ CHUMBLEY, LS KRAMER, MJ DENNIS, KW AF HOLESINGER, TG MILLER, DJ CHUMBLEY, LS KRAMER, MJ DENNIS, KW TI CHARACTERIZATION OF THE PHASE-RELATIONS AND SOLID-SOLUTION RANGE OF THE BI2SR2CA1CU2OY SUPERCONDUCTOR SO PHYSICA C LA English DT Article ID CU-O SYSTEM; PHYSICAL-PROPERTIES; CRYSTAL-CHEMISTRY; SINGLE-CRYSTALS; THIN-FILMS; TC; OXYGEN; EQUILIBRIA AB The phase relationships and solid-solution region of the Bi2Sr2Ca1Cu2Oy (2212) superconductor were investigated for compositions around the ideal 2212 stoichiometry at 865-degrees-C in one bar of oxygen. Changes in the starting composition were accommodated by changes in the types and composition of the secondary phases present, the number of intergrowths within the 2212 phase, and the solid solution composition of the 2212 phase. Compositional analysis of the superconducting phase was carried out in the transmission electron microscope (TEM) in order to separate the effects of solid-solution changes and the presence of intergrowths upon measured compositions. The actual solid-solution region determined from TEM measurements showed most of the solid solution substitution to occur between Sr and Ca. The highest superconducting transition temperatures (T(c)) were found in annealed samples for which the measured Sr+Ca content of the 2212 phase was closest to the ideal stoichiometric ratio of 3 (42.86 at.%). No correlation was found between the transition temperature and lattice parameters of the superconducting phase. C1 ARGONNE NATL LAB,CTR SCI & TECHNOL SUPERCOND,ARGONNE,IL 60439. IOWA STATE UNIV,AMES LAB,AMES,IA 50011. RP HOLESINGER, TG (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. NR 28 TC 62 Z9 62 U1 0 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 NOV 1 PY 1992 VL 202 IS 1-2 BP 109 EP 120 DI 10.1016/0921-4534(92)90302-S PG 12 WC Physics, Applied SC Physics GA JW985 UT WOS:A1992JW98500015 ER PT J AU LIST, FA HSU, H CAVIN, OB PORTER, WD HUBBARD, CR KROEGER, DM AF LIST, FA HSU, H CAVIN, OB PORTER, WD HUBBARD, CR KROEGER, DM TI PHASE DEVELOPMENT IN THE BI2SR2CACU2OY SYSTEM - EFFECTS OF OXYGEN-PRESSURE SO PHYSICA C LA English DT Article ID CA-CU-O; SUPERCONDUCTING PROPERTIES; BI; TEMPERATURE; BEHAVIOR AB Studies have been undertaken using thermal analysis, in conjunction with high-temperature and room temperature X-ray diffraction, to elucidate phase relationships during thermal processing of thick films of initially phase pure Bi2Sr2CaCu2Oy (2212) on silver substrates in various oxygen-containing atmospheres (0.001 to 100% O2). Exothermic events on cooling at 10-degrees-C/min from a partially liquid state vary with oxygen partial pressure and can be grouped into three sets (I-III). Set I is prominent for 0.001% and 0.1% O2 in the range of 740-775-degrees-C and is believed to be associated with the crystallization of a Cu-free approximately Bi5Sr3Ca1 oxide phase. Set II results from the crystallization of 2212; it is observed for p(O2) greater-than-or-equal-to 1.0% in the temperature range 800-870-degrees-C. Set III appears for 21% and 100% O2 in the temperature range 880-910-degrees-C, and its origin is not clear from the results of this study. Subsequent room temperature X-ray diffraction from these samples suggests that in general high oxygen partial pressures (100% O2) tend to favor the formation of Bi2Sr2CuO6 (2201), whereas low oxygen partial pressures (0.001-0.1% O2) lead to the formation of a Cu-free, Bi-Sr-Ca oxide phase. The 2212 phase forms at this cooling rate predominantly for intermediate oxygen partial pressures (7.6-21% O2). High-temperature X-ray diffraction during cooling (2-degrees-C/h) from the partially liquid state shows a pronounced dependence of the order of evolution of crystalline 2212 and 2201 phases on P(O2). For an oxygen partial pressure of 1.0% the formation of 2212 precedes that of 2201, whereas for 0.01% O2 2201 crystallizes at a higher temperature than 2212. The implications of these results pertaining to thermal processing of thick 2212 films are discussed. RP LIST, FA (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 14 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV 1 PY 1992 VL 202 IS 1-2 BP 134 EP 140 DI 10.1016/0921-4534(92)90305-V PG 7 WC Physics, Applied SC Physics GA JW985 UT WOS:A1992JW98500018 ER PT J AU CAMASSA, R HOLM, DD AF CAMASSA, R HOLM, DD TI DISPERSIVE BAROTROPIC EQUATIONS FOR STRATIFIED MESOSCALE OCEAN DYNAMICS SO PHYSICA D LA English DT Article; Proceedings Paper CT 11TH ANNUAL INTERNATIONAL CONF OF THE CENTER FOR NONLINEAR STUDIES ON EXPERIMENTAL MATHEMATICS : COMPUTATIONAL ISSUES IN NONLINEAR SCIENCE CY MAY 20-24, 1991 CL LOS ALAMOS, NM SP CTR NONLINEAR STUDIES EXPTL MATH AB Dispersive effects induced by weak hydrostatic imbalance in the presence of topography and stratification are incorporated into a new model of barotropic (vertically integrated) mesoscale ocean dynamics. This barotropic model is obtained by first expanding the solutions of three dimensional Euler-Boussinesq equations in a regular perturbation expansion in terms of the several small dimensionless parameters appropriate to mesoscale ocean dynamics. Vertically integrating from a fixed bottom topography to the free surface interface with the atmosphere and balancing orders in the expansion at fourth order in the small aspect ratio parameter then yields a system of reduced barotropic equations. These reduced barotropic equations are considerably more tractable than the starting equations and have appropriate limits to known dispersive wave equations such as the forced Kadomtsev-Petviashvili equation in one limit, and the rotating shallow water equations in another. This new model of barotropic ocean dynamics may be of use in developing numerical algorithms for global ocean circulation modeling. C1 LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP CAMASSA, R (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. OI Holm, Darryl D/0000-0001-6362-9912 NR 10 TC 12 Z9 12 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 1 EP 15 DI 10.1016/0167-2789(92)90223-A PG 15 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600002 ER PT J AU KAO, CYJ AF KAO, CYJ TI A NONLINEAR FEEDBACK IN CLIMATE MODELING ASSOCIATED WITH CUMULUS PARAMETERIZATIONS SO PHYSICA D LA English DT Article; Proceedings Paper CT 11TH ANNUAL INTERNATIONAL CONF OF THE CENTER FOR NONLINEAR STUDIES ON EXPERIMENTAL MATHEMATICS : COMPUTATIONAL ISSUES IN NONLINEAR SCIENCE CY MAY 20-24, 1991 CL LOS ALAMOS, NM SP CTR NONLINEAR STUDIES EXPTL MATH ID GENERAL-CIRCULATION MODEL; SIMULATIONS AB A numerical experiment with the Los Alamos general circulation model reveals a marked sensitivity of simulated climate to the treatment of cumulus convection. The diabatic heating produced by the cumulus parameterization not only directly affects the temperature field but also introduces a change of cloudiness which, in tum, alters radiative forcing to the temperature field. The wind fields are also affected through their thermodynamic relationship with temperature. RP KAO, CYJ (reprint author), LOS ALAMOS NATL LAB,DIV EARTH & ENVIRONM SCI,LOS ALAMOS,NM 87545, USA. NR 7 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 62 EP 69 PG 8 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600005 ER PT J AU PUCKETT, EG SALTZMAN, JS AF PUCKETT, EG SALTZMAN, JS TI A 3D ADAPTIVE MESH REFINEMENT ALGORITHM FOR MULTIMATERIAL GAS-DYNAMICS SO PHYSICA D LA English DT Article; Proceedings Paper CT 11TH ANNUAL INTERNATIONAL CONF OF THE CENTER FOR NONLINEAR STUDIES ON EXPERIMENTAL MATHEMATICS : COMPUTATIONAL ISSUES IN NONLINEAR SCIENCE CY MAY 20-24, 1991 CL LOS ALAMOS, NM SP CTR NONLINEAR STUDIES EXPTL MATH ID SHOCK AB Adaptive mesh refinement (AMR) in conjunction with high order upwind finite difference methods has been used effectively on a variety of problems. In this paper we discuss an implementation of an AMR finite difference method that solves the equations of gas dynamics with two material species in three dimensions. An equation for the evolution of volume fractions augments the gas dynamics system. The material interface is preserved and tracked from the volume fractions using a piecewise linear reconstruction technique. C1 UNIV CALIF DAVIS,INST THEORET DYNAM,DAVIS,CA 95616. LOS ALAMOS NATL LAB,COMP RES GRP C-3,LOS ALAMOS,NM 87545. RP PUCKETT, EG (reprint author), UNIV CALIF DAVIS,DEPT MATH,DAVIS,CA 95616, USA. OI Puckett, Elbridge Gerry/0000-0002-6589-7395 NR 14 TC 27 Z9 28 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 84 EP 93 DI 10.1016/0167-2789(92)90228-F PG 10 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600007 ER PT J AU COX, AN DEUPREE, RG GEHMEYR, M AF COX, AN DEUPREE, RG GEHMEYR, M TI ON ADAPTIVE-GRID COMPUTATIONS OF VARIABLE-STARS SO PHYSICA D LA English DT Article; Proceedings Paper CT 11TH ANNUAL INTERNATIONAL CONF OF THE CENTER FOR NONLINEAR STUDIES ON EXPERIMENTAL MATHEMATICS : COMPUTATIONAL ISSUES IN NONLINEAR SCIENCE CY MAY 20-24, 1991 CL LOS ALAMOS, NM SP CTR NONLINEAR STUDIES EXPTL MATH AB We show that the use of an implicit adaptive-grid technique is an efficient and up-to-date approach for the calculations of radial oscillations in variable stars. We chose as an illustrative example the radiative envelope of an RR Lyrae variable. For the hydrostatic initial model we compare the Lagrangian ratioed zoning with an adaptive-grid rezoning. We show that the adaptive-grid yields an optimal distribution of the mesh points in the sense that the relevant physical features, the hydrogen and first and second helium ionization zones, are well resolved. For the hydrodynamical evolution we present the full-amplitude model for both the Lagrangian and adaptive-grid computations. We perform a detailed comparison and show that the adaptive-grid method yields limit cycle solutions that are substantially improved over the Lagrangian grid model. This is due to the fact that the Lagrangian mesh sweeps through the ionization zones twice during one oscillation period, whereas the adaptive-mesh resolves them and tracks them continuously. The results are, in particular, smooth radial velocity and light curves. Beyond a physically better defined solution we also observe larger time steps for the convergence towards the limit cycle and for the evolution during one period. C1 LOS ALAMOS NATL LAB,DIV FIELD TEST,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP COX, AN (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 12 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 139 EP 159 DI 10.1016/0167-2789(92)90231-B PG 21 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600010 ER PT J AU MARGOLIN, LG JONES, DA AF MARGOLIN, LG JONES, DA TI AN APPROXIMATE INERTIAL MANIFOLD FOR COMPUTING BURGERS-EQUATION SO PHYSICA D LA English DT Article; Proceedings Paper CT 11TH ANNUAL INTERNATIONAL CONF OF THE CENTER FOR NONLINEAR STUDIES ON EXPERIMENTAL MATHEMATICS : COMPUTATIONAL ISSUES IN NONLINEAR SCIENCE CY MAY 20-24, 1991 CL LOS ALAMOS, NM SP CTR NONLINEAR STUDIES EXPTL MATH ID NAVIER-STOKES EQUATIONS AB We present a numerical scheme for the approximation of nonlinear evolution equations over large time intervals. Our algorithm is motivated from the dynamical systems point of view. In particular, we adapt the methodology of approximate inertial manifolds to a finite difference scheme. This leads to a differential treatment in which the higher (i.e. unresolved) modes are expressed in terms of the lower modes. As a particular example we derive an approximate inertial manifold for Burgers' equation and develop a numerical algorithm suitable for computing. We perform a parameter study in which we compare the accuracy of a standard scheme with our modified scheme. For all values of the parameters (which are the coefficient of viscosity and the cell size), we obtain a decrease in the numerical error by at least a factor of 2.0 with the modified scheme. The decrease in error is substantially greater over large regions of the parameter space. C1 UNIV CALIF IRVINE,IRVINE,CA 92717. RP MARGOLIN, LG (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 14 TC 18 Z9 18 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 175 EP 184 DI 10.1016/0167-2789(92)90234-E PG 10 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600013 ER PT J AU WENDROFF, B AF WENDROFF, B TI COMPOSITE FLOWS SO PHYSICA D LA English DT Article; Proceedings Paper CT 11TH ANNUAL INTERNATIONAL CONF OF THE CENTER FOR NONLINEAR STUDIES ON EXPERIMENTAL MATHEMATICS : COMPUTATIONAL ISSUES IN NONLINEAR SCIENCE CY MAY 20-24, 1991 CL LOS ALAMOS, NM SP CTR NONLINEAR STUDIES EXPTL MATH AB Composite flow models are an extension of the equations for a single compressible gas to flows with multiple components, multiple phases, or multiple layers. Examples of such flows include the transport of oil, water, and polymers in porous reservoirs; separation of adsorbable solutes by chromatography; distillation columns; thermoclines in the ocean; multiphase flows in reactors; and separation of DNA fragments by electrophoresis. In many examples local equilibrium assumptions, such as Darcy's law or the Langmuir isotherm assumption, lead to nonlinear hyperbolic conservation laws which can be analyzed in terms of Riemann problems and elementary waves. In these cases front tracking algorithms show great promise for resolving very complicated wave interactions, in one dimension. We survey some of the recent developments in this field and present some computational examples. When local equilibrium assumptions are inappropriate, as is the case in many multiphase and multilayer flows, considerable difficulties, both theoretical and numerical, arise from the fact that the equations may be neither hyperbolic nor in conservation form. We give some examples of this and discuss the possibilities for analyzing these flows in terms of elementary and solitary waves. RP WENDROFF, B (reprint author), LOS ALAMOS NATL LAB,DIV T,MS B284,LOS ALAMOS,NM 87545, USA. NR 14 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 208 EP 215 DI 10.1016/0167-2789(92)90237-H PG 8 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600016 ER PT J AU WACKERBAUER, R MAYERKRESS, G HUBLER, A AF WACKERBAUER, R MAYERKRESS, G HUBLER, A TI ALGEBRAIC CALCULATION OF STROBOSCOPIC MAPS OF ORDINARY, NONLINEAR DIFFERENTIAL-EQUATIONS SO PHYSICA D LA English DT Article; Proceedings Paper CT 11TH ANNUAL INTERNATIONAL CONF OF THE CENTER FOR NONLINEAR STUDIES ON EXPERIMENTAL MATHEMATICS : COMPUTATIONAL ISSUES IN NONLINEAR SCIENCE CY MAY 20-24, 1991 CL LOS ALAMOS, NM SP CTR NONLINEAR STUDIES EXPTL MATH ID NON-LINEAR SYSTEMS; CHAOS AB The relation between the parameters of a differential equation and corresponding discrete maps is becoming increasingly important in the study of nonlinear dynamical systems. Maps are well adopted for numerical computation and several universal properties of them are known. Therefore some perturbation methods have been proposed to deduce them for physical systems, which can be modeled by an ordinary differential equation (ODE) with a small nonlinearity. An iterative, rigorous algebraic method for the calculation of the coefficients of a Taylor expansion of a stroboscopic map from ODEs with not necessarily small nonlinearities is presented. It is shown analytically that most of the coefficients are small for a small integration time and grow slowly in the course of time if the flow vector field of the ODE is a polynomial in the state variables and if the ODE has a fixed point at the origin. For several nonlinear systems approximations of different orders are investigated. C1 LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. UNIV CALIF SANTA CRUZ,DEPT MATH,SANTA CRUZ,CA 95064. UNIV ILLINOIS,CTR COMPLEX SYST RES,URBANA,IL 61801. RP WACKERBAUER, R (reprint author), MAX PLANCK INST EXTRATERRESTR PHYS,W-8046 GARCHING,GERMANY. NR 32 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 335 EP 357 DI 10.1016/0167-2789(92)90250-Q PG 23 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600029 ER PT J AU SMITH, RD DUKOWICZ, JK MALONE, RC AF SMITH, RD DUKOWICZ, JK MALONE, RC TI PARALLEL OCEAN GENERAL-CIRCULATION MODELING SO PHYSICA D-NONLINEAR PHENOMENA LA English DT Article ID LINEAR-SYSTEMS AB We have developed a global ocean model on the massively parallel CM-2 Connection Machine based on the Bryan-Cox-Semtner ocean general circulation model. This paper discusses the Connection Machine implementation of the model and its performance, as well as major changes that were made in the algorithms and numerical methods. In order to increase the parallel efficiency, we reformulated the barotropic equations to solve for the surface-pressure field rather than the volume-transport streamfunction. In addition to being more efficient, this method has several other advantages over the streamfunction formulation: (1) any number of islands can be included in the computational grid at no extra cost; (2) the model can handle steep gradients in the bottom topography; and (3) the free-surface height is a prognostic variable, which simplifies assimilation of altimetric data into the model. We have also developed a new parallelizable preconditioning method for the solution of the elliptic equation for the surface-pressure field. In order to use a standard conjugate gradient algorithm, an approximate-factorization technique is used to split off the Coriolis terms and obtain a symmetric operator. We then apply a symmetric local approximate-inverse operator as a preconditioning matrix, which is very effective in accelerating convergence to a solution, RP SMITH, RD (reprint author), LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. NR 24 TC 250 Z9 260 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 EI 1872-8022 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 38 EP 61 DI 10.1016/0167-2789(92)90225-C PG 24 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600004 ER PT J AU HYMAN, JM KNAPP, RJ SCOVEL, JC AF HYMAN, JM KNAPP, RJ SCOVEL, JC TI HIGH-ORDER FINITE VOLUME APPROXIMATIONS OF DIFFERENTIAL-OPERATORS ON NONUNIFORM GRIDS SO PHYSICA D-NONLINEAR PHENOMENA LA English DT Article AB When computing numerical solutions to partial differential equations, difference operators that mimic the crucial properties of the differential operators are usually more accurate than those that do not. Properties such as symmetry, conservation, stability, and the duality relationships and identities between the gradient, curl, and divergence operators are all important. Using the finite volume method, we have derived local, accurate, reliable and efficient difference methods that mimic these properties on nonuniform rectangular and cuboid grids. In a finite volume method, the divergence, gradient, and curl operators are defined using a discrete versions of the divergence theorem and Stokes' theorem. These methods are especially powerful on coarse nonuniform grids and in calculations where the mesh moves to track interfaces or shocks. Numerical examples comparing local second and fourth-order finite volume approximations to conservation laws on very rough grids are used to demonstrate the advantages of the higher order methods. C1 LOS ALAMOS NATL LAB, CTR NONLINEAR STUDIES, DIV COMP, LOS ALAMOS, NM 87545 USA. BOWDOIN COLL, DEPT MATH, BRUNSWICK, ME 04011 USA. RP LOS ALAMOS NATL LAB, CTR NONLINEAR STUDIES, DIV THEORET, MS B284, LOS ALAMOS, NM 87545 USA. NR 16 TC 41 Z9 41 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 EI 1872-8022 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 112 EP 138 DI 10.1016/0167-2789(92)90230-K PG 27 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600009 ER PT J AU BRADLEY, JN BRISLAWN, CM AF BRADLEY, JN BRISLAWN, CM TI IMAGE COMPRESSION BY VECTOR QUANTIZATION OF MULTIRESOLUTION DECOMPOSITIONS SO PHYSICA D-NONLINEAR PHENOMENA LA English DT Article AB An image compression scheme is introduced which involves a multiresolution decomposition derived from the wavelet transform. The use of this transformation in image coding is motivated by its similarity to the processing which occurs at the cortical level of the visual system and by the fact that subband coding in general allows the coder to be better matched to the signal statistics. In this work, each subband is coded separately by vector quantization. This work differs from previous wavelet transform coding schemes involving vector quantization in that the quantization parameters for each subband are selected by a nonlinear optimization procedure which involves constraints on the overall bit-rate and the encoding complexity. The multiplicative visual model is reviewed and a motivation for cascading this system with the wavelet transform to give a more complete description of human vision is provided. Empirical results are presented which demonstrate the effectiveness of the technique for compressing monochromatic images. Signal-to-noise ratio measurements are shown which demonstrate the system performance for various selections of bit-rate and complexity. RP LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. NR 32 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 EI 1872-8022 J9 PHYSICA D JI Physica D PD NOV 1 PY 1992 VL 60 IS 1-4 BP 245 EP 258 DI 10.1016/0167-2789(92)90241-E PG 14 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA KC046 UT WOS:A1992KC04600020 ER PT J AU AVGOUSTOGLOU, E JOHNSON, WR PLANTE, DR SAPIRSTEIN, J SHEINERMAN, S BLUNDELL, SA AF AVGOUSTOGLOU, E JOHNSON, WR PLANTE, DR SAPIRSTEIN, J SHEINERMAN, S BLUNDELL, SA TI MANY-BODY PERTURBATION-THEORY FORMULAS FOR ENERGY-LEVELS OF EXCITED-STATES OF CLOSED-SHELL ATOMS SO PHYSICAL REVIEW A LA English DT Article ID ISOELECTRONIC SEQUENCE AB Many-body perturbation-theory formulas are derived for one-particle-one-hole excited states of closed-shell atoms. Both analytic results and Goldstone diagrams complete through third order are presented, and a sample calculation of a transition energy in neonlike xenon is carried out. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP AVGOUSTOGLOU, E (reprint author), UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556, USA. NR 11 TC 25 Z9 25 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD NOV 1 PY 1992 VL 46 IS 9 BP 5478 EP 5488 DI 10.1103/PhysRevA.46.5478 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA JX834 UT WOS:A1992JX83400031 ER PT J AU BERG, H JAGUTZKI, O DORNER, R DUBOIS, RD KELBCH, C SCHMIDTBOCKING, H ULLRICH, J TANIS, JA SCHLACHTER, AS BLUMENFELD, L DETAT, B HAGMANN, S GONZALES, A QUINTEROS, T AF BERG, H JAGUTZKI, O DORNER, R DUBOIS, RD KELBCH, C SCHMIDTBOCKING, H ULLRICH, J TANIS, JA SCHLACHTER, AS BLUMENFELD, L DETAT, B HAGMANN, S GONZALES, A QUINTEROS, T TI DOUBLE IONIZATION OF HELIUM BY HIGH-VELOCITY U90+ IONS SO PHYSICAL REVIEW A LA English DT Article ID FAST CHARGED-PARTICLES; SINGLE IONIZATION; FAST PROTONS; INELASTIC-COLLISIONS; MULTIPLE IONIZATION; STRIPPED IONS; ELECTRON LOSS; N-7+ IONS; IMPACT; ANTIPROTONS AB Double ionization of helium is investigated for 60-, 120-, and 420-MeV/u (upsilon/c =0.34-0.72)U90+-ion impact. The measured double-to-single ionization ratios indicate that, even for these very high velocities, double ionization of the He target results predominantly from independent interactions of the projectile with both target electrons. It is concluded that the asymptotic high-velocity regime for one-step double ionization (i.e., "shakeoff") has not yet been reached even for U90+ projectiles at 420 MeV/u, and, in fact, cannot be reached for projectiles with q greater than or similar to 7, thereby verifying that the ionic charge is fully as important as the velocity in determining the importance of a given ionization mechanism. C1 GESELL SCHWERIONENFORSCH GMBH, W-6000 DARMSTADT, GERMANY. WESTERN MICHIGAN UNIV, KALAMAZOO, MI 49008 USA. LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. KANSAS STATE UNIV AGR & APPL SCI, MANHATTAN, KS 66506 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. RP BERG, H (reprint author), UNIV FRANKFURT, INST KERNPHYS, W-6000 FRANKFURT, GERMANY. RI Doerner, Reinhard/A-5340-2008 OI Doerner, Reinhard/0000-0002-3728-4268 NR 35 TC 28 Z9 28 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 NOV 1 PY 1992 VL 46 IS 9 BP 5539 EP 5544 DI 10.1103/PhysRevA.46.5539 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA JX834 UT WOS:A1992JX83400039 ER PT J AU BARTLETT, RJ WALSH, PJ HE, ZX CHUNG, Y LEE, EM SAMSON, JAR AF BARTLETT, RJ WALSH, PJ HE, ZX CHUNG, Y LEE, EM SAMSON, JAR TI SINGLE-PHOTON DOUBLE IONIZATION OF HE AND NE SO PHYSICAL REVIEW A LA English DT Article ID DOUBLE-PHOTOIONIZATION; RARE-GASES; MULTIPLE PHOTOIONIZATION; SYNCHROTRON RADIATION; ELECTRON-IMPACT; X-RAYS; THRESHOLD; HELIUM; ABSORPTION; ARGON AB The photoionization branching ratio for double ionization has been measured from threshold to 800 eV for Ne and from threshold to 560 eV for He. Both sets of data have an initial rise from threshold, in general agreement with other published results, but the Ne data reach a plateau value above threshold in contrast to some of the other measurements and to the He data. The Ne data reach a value of approximately 13%, while the He data approach a value of approximately 4% before decreasing. A plateau in the He data was not reached in our measurements but may exist at higher energies. The photoionization cross section for double ionization has been extracted from the branching-ratio data. C1 UNIV NEBRASKA,BEHLEN LAB PHYS,LINCOLN,NE 68588. RP BARTLETT, RJ (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 31 TC 47 Z9 47 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 NOV 1 PY 1992 VL 46 IS 9 BP 5574 EP 5579 DI 10.1103/PhysRevA.46.5574 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA JX834 UT WOS:A1992JX83400042 ER PT J AU HERRMANN, R PRIOR, MH DORNER, R SCHMIDTBOCKING, H LYNEIS, CM WILLE, U AF HERRMANN, R PRIOR, MH DORNER, R SCHMIDTBOCKING, H LYNEIS, CM WILLE, U TI MULTIPLE ELECTRON-TRANSFER IN SLOW NE9+-NE COLLISIONS SO PHYSICAL REVIEW A LA English DT Article ID ION-ATOM COLLISIONS; K CHARGE-TRANSFER; S-IONS; CAPTURE; SHELL; MECHANISMS; MOLECULES; PARTICLE; EMISSION; AR AB Multielectron transfer probabilities in 90-keV Ne9+-Ne collisions have been measured with respect to the projectile scattering angle theta in a range between theta=12 and 75 mrad. The projectile final charge state was determined in coincidence with the target-ion final charge state using a time-of-flight technique. For theta > 45 mrad, projectile and target undergo a complete equilibration of their atomic shells (including the K shell) leading to the excitation of both collision partners and the autoionization of three electrons on average. A comparison of the measured final charge-state distributions of projectile and target with those obtained in a former experiment with the system 90-keV Ne7+-Ne [H. Schmidt-Bocking et al., Phys. Rev. A 37, 4640 (1989)] leads to the conclusion that L- and K-shell charge transfer can be treated as independent processes. Interference structure in the K-K vacancy-transfer probabilities has been observed in the final charge-state probabilities of the "heavy-ion"-atom system. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. HAHN MEITNER INST KERNFORSCH BERLIN GMBH,W-1000 BERLIN 39,GERMANY. RP HERRMANN, R (reprint author), UNIV FRANKFURT,INST KERNPHYS,AUGUST EULER STR 6,W-6000 FRANKFURT 90,GERMANY. RI Doerner, Reinhard/A-5340-2008 OI Doerner, Reinhard/0000-0002-3728-4268 NR 34 TC 8 Z9 8 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD NOV 1 PY 1992 VL 46 IS 9 BP 5631 EP 5642 DI 10.1103/PhysRevA.46.5631 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA JX834 UT WOS:A1992JX83400047 ER PT J AU BERRAHMANSOUR, N KURTZ, C YOUNG, L BECK, DR DATTA, D AF BERRAHMANSOUR, N KURTZ, C YOUNG, L BECK, DR DATTA, D TI LASER-RF DOUBLE-RESONANCE MEASUREMENTS OF THE HYPERFINE-STRUCTURE IN TI-49(II) SO PHYSICAL REVIEW A LA English DT Article ID CONSISTENT-FIELD CALCULATIONS; COLLINEAR LASER; SPECTROSCOPY; ATOMS AB The hyperfine structures of six metastable levels arising from the 3d(2)4s and 3d3 configurations in Ti-49 II have been measured with high precision using the laser-rf double-resonance technique in a collinear laser-ion-beam geometry. The hfs constants A and B were determined to about 4 and 43 kHz, respectively. Less precise results are also reported for the 2p1/2 level of the 3d3 configuration and for five upper levels in the 3d(2)4p configuration. For these states, the optical spectra had Doppler widths of about 40 MHz, leading to A values determined to about 1 MHz. The results are compared with the presently available Hartree-Fock (HF) calculations. Good agreement is obtained with the HF results only in some cases. Substantial corrections due to many-body interactions and relativistic effects are required for other cases. C1 WESTERN MICHIGAN UNIV,DEPT PHYS,KALAMAZOO,MI 49009. MICHIGAN TECHNOL UNIV,DEPT PHYS,HOUGHTON,MI 49931. RP BERRAHMANSOUR, N (reprint author), ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439, USA. RI Kurtz, Chalres/G-1037-2011 OI Kurtz, Chalres/0000-0003-2606-0864 NR 27 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 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD NOV 1 PY 1992 VL 46 IS 9 BP 5774 EP 5780 DI 10.1103/PhysRevA.46.5774 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA JX834 UT WOS:A1992JX83400062 ER PT J AU RUBINI, S DIMITROPOULOS, C ALDROVANDI, S BORSA, F TORGESON, DR ZIOLO, J AF RUBINI, S DIMITROPOULOS, C ALDROVANDI, S BORSA, F TORGESON, DR ZIOLO, J TI ELECTRONIC-STRUCTURE AND THE MARTENSITIC-TRANSFORMATION IN BETA-PHASE NI-AL ALLOYS - AL-27 NMR AND SPECIFIC-HEAT MEASUREMENTS SO PHYSICAL REVIEW B LA English DT Article ID CU-ZN-AL; NEUTRON-SCATTERING; THERMOELASTICITY; PSEUDOELASTICITY AB Al-27 NMR line shape, Knight shift, relaxation rates together with low-temperature specific heat and magnetic susceptibiltiy were measured as a function of temperature and external magnetic-field in two Ni-rich beta-phase Ni-Al alloys (62% Ni and 63% Ni) undergoing a martensitic phase transformation (MPT) below room temperature. For the purpose of comparison, two further alloys not undergoing the MPT were investigated (50% Ni and 55% Ni). Regarding the electronic properties of the alloys, we find an increase in the density of states at the Fermi level and a decrease of s-character of the conduction electron wave function as a function of the increase of Ni content from the 1:1 Ni-Al alloy. Furthermore, the inhomogeneous broadening of the Al-27 linewidth indicates that the additional Ni replacing Al at the "wrong" site introduces quasilocalized magnetic states. Regarding the MPT we find a slight decrease of the Knight shift and of the Korringa product (T1T)-1 going from the austenite to the martensite. In the transformation-temperature region, the Al-27 NMR line is broadened by the effect of superposition of two signals arising from the austenite and the transforming phase. The deconvolution of the spectrum gives information about the nucleation and growth of the martensite, which appears to be continuous and involving a succession of intermediate states, in contrast with the abrupt nucleation of fully transformed martensite observed in Cu-Zn-Al. No anomalous enhancement of the relaxation rate is observed above M(s) or during the MPT. Although the NMR cannot rule out the presence of static precursor effects a few degrees above the transformation temperature M(s), no evidence was found for the formation of martensitic regions well above M(s) where tweed patterns are observed by electron microscopy. C1 UNIV PAVIA,DIPARTIMENTO FIS A VOLTA,I-27100 PAVIA,ITALY. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. RP RUBINI, S (reprint author), ECOLE POLYTECH FED LAUSANNE,INST PHYS EXPTL,CH-1015 LAUSANNE,SWITZERLAND. RI Rubini, Silvia/C-8369-2012 OI Rubini, Silvia/0000-0001-5215-2223 NR 32 TC 15 Z9 15 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 NOV 1 PY 1992 VL 46 IS 17 BP 10563 EP 10572 DI 10.1103/PhysRevB.46.10563 PG 10 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600005 ER PT J AU DATTA, S CHAN, CT HO, KM SOUKOULIS, CM AF DATTA, S CHAN, CT HO, KM SOUKOULIS, CM TI PHOTONIC BAND-GAPS IN PERIODIC DIELECTRIC STRUCTURES - THE SCALAR-WAVE APPROXIMATION SO PHYSICAL REVIEW B LA English DT Article ID INHIBITED SPONTANEOUS EMISSION; DISORDERED-SYSTEMS; BOUND-STATES; LOCALIZATION; PROPAGATION; DIFFUSION; MEDIA AB Using a plane-wave expansion method we have computed the band structure for a scalar wave propagating in periodic lattices of dielectric spheres (dielectric constant epsilon(a)) in a uniform dielectric background (epsilon(b)). All of the lattices studied (simple cubic, bcc, fcc, and diamond) do possess a full band gap. The optimal values of the filling ratio f of spheres and of the relative dielectric contrast for the existence of a gap are obtained. The minimum value of the relative dielectric contrast for creating a gap is also obtained. These results are applicable to the problem of classical-wave propagation in composite media and relevant to the problem of classical-wave localization. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50010. RP DATTA, S (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50010, USA. RI Soukoulis, Costas/A-5295-2008 NR 32 TC 27 Z9 27 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1992 VL 46 IS 17 BP 10650 EP 10656 DI 10.1103/PhysRevB.46.10650 PG 7 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600017 ER PT J AU EMIN, D YE, J BECKEL, CL AF EMIN, D YE, J BECKEL, CL TI ELECTRON-CORRELATION EFFECTS IN ONE-DIMENSIONAL LARGE-BIPOLARON FORMATION SO PHYSICAL REVIEW B LA English DT Article AB We study the effects of electron correlation on the ground state of a one-dimensional large singlet bipolaron. The electron-lattice interaction is taken to be the short-range interaction of Holstein's molecular-crystal model. We represent the Coulomb repulsion with the Hubbard short-range repulsion. This adoption of the Hubbard model is equivalent to replacing a strict one-dimensional system that has a short-range logarithmic divergence of the Coulomb repulsion energy between overlapping charges, with a quasi-one-dimensional system of finite width. Two types of electronic correlation are considered. With "in-out" correlation, we permit one of the two self-trapped carriers of bipolaron to have a larger radius than the other. With "left-right" correlation, we permit the centroids of the self-trapped carriers to be displaced from one another. For both types of correlation, variational calculations are performed to determine the magnitudes of the correlation effects in the ground state. There are three parameters in the model: the electronic bandwidth parameter t, the electron-lattice coupling strength E(b), and the Hubbard repulsion, V(c). The electron-lattice interaction provides an indirect intercarrier attraction that fosters the coalescence of the two carriers. In opposition, the carriers' Coulomb repulsion and the kinetic energy required for carrier confinement foster the carriers spreading. With bipolaron formation the intercarrier attraction dominates the Coulomb repulsion. The electron-correlation effect on the bipolaron's binding depends explicitly on only V(c)/E(b). The electron correlation also depends on the shape of the local functions presumed in the variational calculations. Of course, the effects of electron correlation on the bipolaron's ground state increase as the Coulomb repulsion between the carriers is increased. Strikingly, we also find that the dependence of the confinement energy on electronic correlation is critical to promoting electronic correlation in the bipolaron's ground state. This feature is discussed in detail. At a maximum ratio of V(c)/E(b) for which we have stable bipolarons, we find that electronic correlation can lower the ground-state energy of our bipolaron by up to 30%. C1 UNIV NEW MEXICO,DEPT PHYS & ASTRON,ALBUQUERQUE,NM 87131. RP EMIN, D (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. RI Ye, Jun/C-3312-2011 NR 8 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 NOV 1 PY 1992 VL 46 IS 17 BP 10710 EP 10726 DI 10.1103/PhysRevB.46.10710 PG 17 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600025 ER PT J AU EMERY, VJ KIVELSON, S AF EMERY, VJ KIVELSON, S TI MAPPING OF THE 2-CHANNEL KONDO PROBLEM TO A RESONANT-LEVEL MODEL SO PHYSICAL REVIEW B LA English DT Article ID FERMI-LIQUID BEHAVIOR; STATE; SUPERCONDUCTORS; SYSTEMS; METALS AB Abelian bosonization is used to map the two-channel Kondo problem into a resonant-level Hamiltonian, which is equivalent to noninteracting fermions for a particular value of the longitudinal exchange coupling. This solvable point is analogous to the Toulouse limit of the ordinary Kondo problem. The impurity Green's function, susceptibility, and thermodynamic properties, together with certain conduction-electron correlation functions, are evaluated at the solvable point. In particular, it is shown that the pairing resonance of the two-channel Kondo problem may be characterized as an enhancement of superconducting pairing of the conduction electrons at the impurity site, correlated with the impurity pseudospin (or equivalently odd-time pairing of the conduction electrons). C1 UNIV CALIF LOS ANGELES,DEPT PHYS,LOS ANGELES,CA 90024. RP EMERY, VJ (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 33 TC 297 Z9 297 U1 2 U2 8 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 NOV 1 PY 1992 VL 46 IS 17 BP 10812 EP 10817 DI 10.1103/PhysRevB.46.10812 PG 6 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600039 ER PT J AU STRANDBURG, KJ HALL, DW LIU, C BADER, SD AF STRANDBURG, KJ HALL, DW LIU, C BADER, SD TI MONTE-CARLO SIMULATIONS OF THE CURIE-TEMPERATURE OF ULTRATHIN FERROMAGNETIC-FILMS SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC PHASE-TRANSITION; CRITICAL-BEHAVIOR; EPITAXIAL-FILMS; FE FILMS; SURFACES; ORDER; IRON AB A Hamiltonian is considered that describes overlayers of classical Ising spins coupled to a polarizable substrate whose spins can take on continuous values. Monte Carlo simulation techniques are then used to study the temperature dependence of the magnetization for bcc lattices of mesh size 16 X 16 for a variety of coverages, coupling strengths, and overlayer morphologies. A primary motivation is to develop insights into the Fe thickness dependence of the Curie temperature measured experimentally for the Fe/Pd(100) system by Liu and Bader, especially the pronounced variation observed in the submonolayer Fe regime. We are able to capture the essential physics of the problem using a random-site-vacancy model, as opposed to a two-dimensional-island model, in accord with the results of recent photoemission efforts to characterize the morphology of the films. RP STRANDBURG, KJ (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Bader, Samuel/A-2995-2013 NR 23 TC 21 Z9 21 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1992 VL 46 IS 17 BP 10818 EP 10821 DI 10.1103/PhysRevB.46.10818 PG 4 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600040 ER PT J AU MAHAJAN, AV JOHNSTON, DC TORGESON, DR BORSA, F AF MAHAJAN, AV JOHNSTON, DC TORGESON, DR BORSA, F TI MAGNETIC-PROPERTIES OF LAVO3 SO PHYSICAL REVIEW B LA English DT Article AB Herein, we report on the magnetic properties of LaVO3. We have observed diamagnetism in this compound, which is an antiferromagnetic insulator, below the Neel temperature under field-cooled conditions. We observe hysteresis in magnetization versus applied field M(H) isotherms below the Neel temperature. LaVO3 has a ferromagnetic component to the spin ordering, due to canting of spins and/or due to ferrimagnetism. Four-probe resistivity measurements rule out the possibility of superconductivity and the dimagnetism appears to be associated with uncompensated antiferromagnetism (ferrimagnetism). From our V-51 NMR measurements on LaVO3 we associate the kink in susceptibility with magnetic ordering. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. NR 24 TC 99 Z9 99 U1 6 U2 28 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 NOV 1 PY 1992 VL 46 IS 17 BP 10966 EP 10972 DI 10.1103/PhysRevB.46.10966 PG 7 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600058 ER PT J AU MAHAJAN, AV JOHNSTON, DC TORGESON, DR BORSA, F AF MAHAJAN, AV JOHNSTON, DC TORGESON, DR BORSA, F TI STRUCTURAL, ELECTRONIC, AND MAGNETIC-PROPERTIES OF LAXSR1-X VO3 (0.1-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-1.0) SO PHYSICAL REVIEW B LA English DT Article ID LANTHANUM STRONTIUM VANADATE; METAL-INSULATOR TRANSITION; SUPERCONDUCTIVITY; SYSTEM; TRANSPORT; OXIDES; NQR; NMR AB We report on the properties of LaxSr1-xVO3 which has a phase diagram which is similar to Sr-doped La2CuO4 in that it too shows a composition-induced insulator-to-metal transition with strontium doping. In addition, the fact that the insulating compositions in the vanadium-based system are antiferromagnetic, as well as, the perovskite structure of LaxSr1-xVO3, makes them candidates for a detailed study of their properties in order to gain greater insight into the mechanisms at play in the high-T(c) cuprate superconductors. Magnetic susceptibility, x-ray powder diffraction, and V-51 NMR Knight shift and relaxation rates, T1(-1) and T-2(-1), are reported as functions of temperature and composition in LaxSr1-xVO3. A combined analysis of the susceptibility and the V-51 NMR data yields values of the density of states D (epsilon(f)) and for the enhancement of the uniform susceptibility. These are indicative of a strongly exchange-enhanced narrow d-band metal for x < 0.7. No evidence was found for antiferromagnetic spin fluctuations in the metallic phase nor for superconducting behavior, in contrast to cuprate superconductors where neutron-scattering evidence shows antiferromagnetic spin correlations in the normal state of the superconducting compositions. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. NR 50 TC 38 Z9 38 U1 1 U2 11 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 NOV 1 PY 1992 VL 46 IS 17 BP 10973 EP 10985 DI 10.1103/PhysRevB.46.10973 PG 13 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600059 ER PT J AU CAI, ZX ZHU, YM WELCH, DO AF CAI, ZX ZHU, YM WELCH, DO TI OXYGEN ORDERING AND STRAIN-RELATED MORPHOLOGY IN YBA2CU3-XMXO7 SYSTEMS, WHERE M IS A TRIVALENT ATOM SO PHYSICAL REVIEW B LA English DT Article ID BASAL-PLANE; MONTE-CARLO; YBA2CU3O7-DELTA; SCATTERING AB Monte Carlo simulations were performed on an anisotropic lattice-gas model which well represents the interactions between oxygen atoms in YBa2Cu3O7 systems doped with trivalent impurity atoms M such as Fe or Al. Concentration wave amplitudes obtained from these simulations were used to calculate the diffuse x-ray scattering intensity caused by the resulting displacement field using a concentration-wave-displacement-wave approach, and the results are compared with x-ray and electron diffraction data. The results suggest that the small orthorhombic domains (short-range ordering) associated with the oxygen "cross-links" around impurity atoms M cause the diffuse scattering intensity to fall off with the scattering wave-vector difference q from a Bragg peak as 1/q2 for small q and as 1/q4 for larger q. We show that the average size of such domains can be obtained from diffuse x-ray scattering data. RP CAI, ZX (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,DIV MAT SCI,UPTON,NY 11973, USA. NR 11 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 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1992 VL 46 IS 17 BP 11014 EP 11018 DI 10.1103/PhysRevB.46.11014 PG 5 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600063 ER PT J AU LIU, R VEAL, BW PAULIKAS, AP DOWNEY, JW KOSTIC, PJ FLESHLER, S WELP, U OLSON, CG WU, X ARKO, AJ JOYCE, JJ AF LIU, R VEAL, BW PAULIKAS, AP DOWNEY, JW KOSTIC, PJ FLESHLER, S WELP, U OLSON, CG WU, X ARKO, AJ JOYCE, JJ TI FERMI-SURFACE TOPOLOGY OF YBA2CU3OX WITH VARIED OXYGEN STOICHIOMETRY - A PHOTOEMISSION-STUDY SO PHYSICAL REVIEW B LA English DT Article ID ANGLE-RESOLVED PHOTOEMISSION; CHARGE-TRANSFER EXCITATIONS; HIGH-TC SUPERCONDUCTIVITY; NORMAL-STATE PROPERTIES; CA-CU-O; ELECTRONIC-STRUCTURE; SINGLE-CRYSTALS; TEMPERATURE; BI2SR2CACU2O8; FIELD AB High-resolution angle-resolved photoemission measurements are reported for YBa2Cu3Ox when oxygen stoichiometry x was varied between 6.3 and 6.9. Fermi surfaces were measured and their dependence on oxygen stoichiometry was monitored by observing the dispersing behavior of spectral features, scanning the entire first Brillouin zone. For x = 6.9, measured Fermi surfaces correspond very well with the plane-related Fermi surfaces calculated from band theory. Relatively small changes in Fermi surfaces were observed when oxygen stoiochiometry was varied in the range 6.5 less-than-or-equal-to x less-than-or-equal-to 6.9, where the material is metallic. However, significant changes in the spectral behavior were observed when the material becomes insulating. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP LIU, R (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. NR 56 TC 153 Z9 155 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 NOV 1 PY 1992 VL 46 IS 17 BP 11056 EP 11068 DI 10.1103/PhysRevB.46.11056 PG 13 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600069 ER PT J AU LEWIS, SP COHEN, ML AF LEWIS, SP COHEN, ML TI HIGH-PRESSURE ATOMIC PHASES OF SOLID NITROGEN SO PHYSICAL REVIEW B LA English DT Note ID BLACK PHOSPHORUS; PSEUDOPOTENTIALS; TRANSITION; STABILITY; ELEMENTS AB Several candidate atomic phases for solid nitrogen at high pressures have been studied theoretically. The semimetallic A7 (alpha-arsenic) phase is found to be the most energetically favored of the atomic phases studied which agrees with previous calculations. At extremely high pressures, this phase is found to deform continuously into the metallic simple cubic structure which is unstable at lower pressures. The possibility that a metallic simple tetragonal phase is metastable at lower pressures is discussed. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP LEWIS, SP (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. NR 23 TC 31 Z9 34 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 NOV 1 PY 1992 VL 46 IS 17 BP 11117 EP 11120 DI 10.1103/PhysRevB.46.11117 PG 4 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600076 ER PT J AU GRONBECHJENSEN, N BISHOP, AR FALO, F LOMDAHL, PS AF GRONBECHJENSEN, N BISHOP, AR FALO, F LOMDAHL, PS TI FLUX-LATTICE NOISE AND SYMMETRY-BREAKING IN FRUSTRATED JOSEPHSON-JUNCTION ARRAYS SO PHYSICAL REVIEW B LA English DT Note ID POSITIONAL DISORDER; SUPERCONDUCTORS; SIMULATIONS AB Long-time dynamics simulations of large (128 X 128) two-dimensional arrays of Josephson junctions in a uniformly frustrating external magnetic field are reported. The results demonstrate (i) a noisy transverse voltage response to an applied current, and (ii) the dependence of the noise on both positional disorder and intrinsic dynamical symmetry breaking induced by boundaries as nucleation sites for flux-lattice defects, which propagate into the interior and control the noise characteristics. C1 LOS ALAMOS NATL LAB, ADV COMP LAB, LOS ALAMOS, NM 87545 USA. STANFORD UNIV, STANFORD, CA 94305 USA. UNIV SARAGOSSA, CSIC, DEPT CIENCIA & TECNOL MAT & FLUIDOS, ZARAGOZA, SPAIN. RP GRONBECHJENSEN, N (reprint author), LOS ALAMOS NATL LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. RI Falo, Fernando/B-9137-2011 OI Falo, Fernando/0000-0002-9551-624X NR 28 TC 17 Z9 17 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 NOV 1 PY 1992 VL 46 IS 17 BP 11149 EP 11152 DI 10.1103/PhysRevB.46.11149 PG 4 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600084 ER PT J AU LEE, JY STRANDBURG, KJ AF LEE, JY STRANDBURG, KJ TI 1ST-ORDER MELTING TRANSITION OF THE HARD-DISK SYSTEM SO PHYSICAL REVIEW B LA English DT Note ID MONTE-CARLO TECHNIQUE; LENNARD-JONES SYSTEM; PHASE-TRANSITIONS; ORIENTATIONAL ORDER; COMPLEX ZEROS; MODEL; LATTICES AB We present a very strong evidence for a first-order melting transition in the hard-disk system by exploiting the finite-size scaling of the bulk free-energy barrier. We use isobaric Monte Carlo simulations to allow fluctuations in the volume of the system, which lead, in the presence of a first-order transition, to a double-peaked structure in the volume distribution. We also find that the system melts directly from a two-dimensional solid with long-range orientational order to an isotropic liquid with no intervening hexatic phase. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. NR 29 TC 99 Z9 99 U1 0 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 NOV 1 PY 1992 VL 46 IS 17 BP 11190 EP 11193 DI 10.1103/PhysRevB.46.11190 PG 4 WC Physics, Condensed Matter SC Physics GA JW976 UT WOS:A1992JW97600095 ER PT J AU HAASE, DG BOWMAN, JD DELHEIJ, PPJ FRANKLE, CM GOULD, CR KNUDSON, JN KOSTER, JE MITCHELL, GE PENTTILA, S POSTMA, H ROBERSON, NR SEESTROM, SJ YOO, SH YUAN, VW AF HAASE, DG BOWMAN, JD DELHEIJ, PPJ FRANKLE, CM GOULD, CR KNUDSON, JN KOSTER, JE MITCHELL, GE PENTTILA, S POSTMA, H ROBERSON, NR SEESTROM, SJ YOO, SH YUAN, VW TI DEPOLARIZATION OF NEUTRONS IN FERROMAGNETIC HOLMIUM BY MEANS OF ENHANCED NUCLEAR PARITY VIOLATION IN LA-139 SO PHYSICAL REVIEW B LA English DT Article AB The depolarization of epithermal neutrons in a thick single crystal of ferromagnetic holmium has been measured and analyzed with a model of neutron precession through a highly correlated array of magnetic domains. The large parity violation in the 0.734-eV p-wave resonance in La-139 was used to analyze the neutron polarization, and represents an application of parity violation in nuclear resonances to a measurement in condensed-matter physics. C1 TRIANGLE UNIV NUCL LAB,DURHAM,NC 27706. TRIUMF,VANCOUVER V6T 2A3,BC,CANADA. UNIV TECHNOL DEPT,2600 GA DELFT,NETHERLANDS. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. DUKE UNIV,DEPT PHYS,DURHAM,NC 27706. RP HAASE, DG (reprint author), N CAROLINA STATE UNIV,DEPT PHYS,RALEIGH,NC 27695, USA. RI Gould, Christopher/M-7676-2013 NR 14 TC 3 Z9 3 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 NOV 1 PY 1992 VL 46 IS 18 BP 11290 EP 11294 DI 10.1103/PhysRevB.46.11290 PG 5 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900003 ER PT J AU PRICE, DL COOPER, BR WILLS, JM AF PRICE, DL COOPER, BR WILLS, JM TI FULL-POTENTIAL LINEAR-MUFFIN-TIN-ORBITAL STUDY OF BRITTLE-FRACTURE IN TITANIUM CARBIDE SO PHYSICAL REVIEW B LA English DT Article ID ELECTRON AB The inelastic behavior of the refractory transition-metal carbides is dominated, at low temperatures, by brittle fracture. We discuss in this article our theoretical study of both the elastic and fracture properties of titanium carbide under tensile stress. The calculations involved were performed using a full-potential linear-muffin-tin-orbital electronic structure method, with a repeated slab arrangement of atoms simulating an isolated cleavage plane. We report results for the elastic constants (excluding the shear modulus), the stress-strain relationship up to the point of fracture, and the ideal yield stress and strain for stoichiometric TiC. We relate these properties to the details of the electronic structure and to the breaking of metal-nonmetal covalent bonds at the cleavage plane. This includes a detailed pictorial analysis of the charge redistribution accompanying cleavage. C1 W VIRGINIA UNIV,DEPT PHYS,MORGANTOWN,WV 26506. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP PRICE, DL (reprint author), MEMPHIS STATE UNIV,DEPT PHYS,MEMPHIS,TN 38152, USA. NR 15 TC 61 Z9 64 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 NOV 1 PY 1992 VL 46 IS 18 BP 11368 EP 11375 DI 10.1103/PhysRevB.46.11368 PG 8 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900011 ER PT J AU COFFEY, MW CLEM, JR AF COFFEY, MW CLEM, JR TI THEORY OF HIGH-FREQUENCY LINEAR RESPONSE OF ISOTROPIC TYPE-II SUPERCONDUCTORS IN THE MIXED STATE SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TC SUPERCONDUCTORS; RF SURFACE IMPEDANCE; FLUX CREEP; BI2SR2CACU2O8+DELTA; YBA2CU3O7-DELTA; FLOW AB A self-consistent approach to vortex dynamics, including the effects of nonlocal vortex interaction, pinning, and creep, is further clarified and unified by its restatement in terms of an initial-boundary value problem. We derive and solve a single vector partial differential equation describing the linear response of a type-II superconductor in the mixed state at frequencies well below the gap frequency. The solution of this equation, presented here for several sample geometries, provides the phenomenological superconductor dispersion relation, accompanying complex penetration depths, and complex response functions. The theory is expected to have applicability to a wide range of experiments involving vortex dynamics. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. RP COFFEY, MW (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 36 TC 81 Z9 81 U1 0 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 NOV 1 PY 1992 VL 46 IS 18 BP 11757 EP 11764 DI 10.1103/PhysRevB.46.11757 PG 8 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900056 ER PT J AU BULAEVSKII, LN LEDVIJ, M KOGAN, VG AF BULAEVSKII, LN LEDVIJ, M KOGAN, VG TI DISTORTED VORTEX IN JOSEPHSON-COUPLED LAYERED SUPERCONDUCTORS SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TC SUPERCONDUCTORS; MAGNETIC-FIELD; TYPE-2 SUPERCONDUCTORS; II SUPERCONDUCTORS; ORDER PARAMETER; ELASTIC ENERGY; FLUX LINES; LATTICE; VORTICES; STATE AB The free energy functional for a single vortex in a system of Josephson-coupled superconducting layers is derived in terms of coordinates of two-dimensional vortices, "pancakes," which make the vortex "line." The energy consists of equally important two-, three-, and four-pancake interactions. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. INST PHYS,YU-11001 BELGRADE,YUGOSLAVIA. RP BULAEVSKII, LN (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 23 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 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1992 VL 46 IS 18 BP 11807 EP 11812 DI 10.1103/PhysRevB.46.11807 PG 6 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900063 ER PT J AU WELLS, BO SHEN, ZX DESSAU, DS SPICER, WE MITZI, DB LOMBARDO, L KAPITULNIK, A ARKO, AJ AF WELLS, BO SHEN, ZX DESSAU, DS SPICER, WE MITZI, DB LOMBARDO, L KAPITULNIK, A ARKO, AJ TI EVIDENCE FOR K-DEPENDENT, INPLANE ANISOTROPY OF THE SUPERCONDUCTING GAP IN BI2SR2CACU2O8+DELTA SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; ANGLE-RESOLVED-PHOTOEMISSION; RESONATING VALENCE BONDS; D-WAVE SUPERCONDUCTIVITY; HIGH-TC SUPERCONDUCTORS; CA-CU-O; PARAMETER; YBA2CU3O7; ENERGIES; SYMMETRY AB We find the superconducting gap in Bi2Sr2CaCu2O8+delta single crystals is anisotropic in k space by roughly a factor of 2 using angle-resolved photoemission spectroscopy. Matching the k-space symmetry of the gap values provides a stringent constraint on theories of the mechanism of high-temperature superconductivity. A review of the literature shows that many puzzling results can be explained by anisotropic gaps in the high-T(c) cuprates. C1 STANFORD UNIV,DEPT APPL PHYS,STANFORD,CA 94305. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP WELLS, BO (reprint author), STANFORD UNIV,STANFORD ELECTR LABS,STANFORD,CA 94305, USA. RI Mitzi, David/B-6260-2012 OI Mitzi, David/0000-0001-5189-4612 NR 28 TC 57 Z9 57 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 NOV 1 PY 1992 VL 46 IS 18 BP 11830 EP 11834 DI 10.1103/PhysRevB.46.11830 PG 5 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900066 ER PT J AU SICKAFUS, KE WILLIS, JO KUNG, PJ WILSON, WB PARKIN, DM MALEY, MP CLINARD, FW SALGADO, CJ DYE, RP HUBBARD, KM AF SICKAFUS, KE WILLIS, JO KUNG, PJ WILSON, WB PARKIN, DM MALEY, MP CLINARD, FW SALGADO, CJ DYE, RP HUBBARD, KM TI NEUTRON-RADIATION-INDUCED FLUX PINNING IN GD-DOPED YBA2CU3O7-X AND GDBA2CU3O7-X SO PHYSICAL REVIEW B LA English DT Article ID IRRADIATION; CURRENTS; SPINEL AB The critical current density J(c) in Y0.9Gd0.1Ba2Cu307-x was found to increase relative to the unirradiated value following neutron irradiations in a mixed-spectrum reactor (total neutron fluences ranged between 1 X 10(17) and 2 X 10(18) n/cm2 ). Additional neutron irradiations of structurally similar GdBa2Cu307-x were carried out in either a highly thermalized or a pure fast-neutron environment (in the same reactor). This was done to determine whether enhancements in J(c) are to be attributed to defects arising from interactions with thermal neutrons (E(n) approximately 0.025 eV) or with fast neutrons (E(n) > 0.1 MeV). Magnetic-hysteresis measurements on these samples indicate that flux pinning (and thereby J(c)) is enhanced by fast-neutron irradition, but not by thermal-neutron irradiation. On the other hand, the critical temperature T(c) is significantly altered by exposure both to thermal and fast neutrons. It is proposed that thermal neutrons induce the formation of Frenkel pair defects on the rare-earth sublattice, but that these point defects do not serve as effective flux-pinning centers. C1 SUPERCOND RES LAB,KOTO KU,TOKYO 135,JAPAN. RP SICKAFUS, KE (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 35 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 NOV 1 PY 1992 VL 46 IS 18 BP 11862 EP 11870 DI 10.1103/PhysRevB.46.11862 PG 9 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900071 ER PT J AU LAN, MD LIU, JZ SHELTON, RN RADOUSKY, HB VEAL, BW DOWNEY, JW AF LAN, MD LIU, JZ SHELTON, RN RADOUSKY, HB VEAL, BW DOWNEY, JW TI MAGNETIC-PROPERTIES OF OXYGEN-DEPLETED YBA2CU3O7-Y SINGLE-CRYSTALS SO PHYSICAL REVIEW B LA English DT Article ID FLUX CREEP; CURRENTS; FIELD AB Magnetic properties and flux pinning of oxygen-deficient YBa2Cu3O7-y single crystals have been studied. The superconducting transition temperature and inductive critical current density decrease as the level of oxygen depletion increases. No obvious enhancement in the pinning strength was found in the oxygen-depleted YBa2Cu307-y system for the applied field along the c axis. We attribute this absence of enhanced pinning to the mismatch of the oxygen vacancy size with the superconducting coherence length over the entire superconducting regime. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. ARGONNE NATL LAB,ARGONNE,IL 60439. RP LAN, MD (reprint author), UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616, USA. NR 16 TC 6 Z9 6 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1992 VL 46 IS 18 BP 11919 EP 11922 DI 10.1103/PhysRevB.46.11919 PG 4 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900076 ER PT J AU XU, M UMEZAWA, A CRABTREE, GW AF XU, M UMEZAWA, A CRABTREE, GW TI FIELD AND TEMPERATURE-DEPENDENCE OF REMANENT MAGNETIZATION IN A SINGLE-CRYSTAL OF BI2SR2CACU2OY SO PHYSICAL REVIEW B LA English DT Article ID BA-CU-O; CRITICAL-STATE MODELS; HIGH-TC SUPERCONDUCTORS; II SUPERCONDUCTORS; HARD SUPERCONDUCTORS; FLUX CREEP; PENETRATION DEPTH; CRITICAL CURRENTS; SURFACE BARRIERS; IRREVERSIBILITY AB We report the studies of the virgin and remanent magnetization in a single crystal of Bi2Sr2CaCU2Oy over a wide range of fields and temperatures. Based on the critical-state model, the field and temperature-dependence of the magnetization can be well understood. The first and second penetration fields have been estimated, based upon the measurements of the magnetization in a single crystal of Bi2Sr2CaCu2Oy. Also discussed are flux pinning, applications of the critical-state model, and related issues in this material. C1 IOWA STATE UNIV SCI & TECHNOL,AMES,IA 50011. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP XU, M (reprint author), AMES LAB,AMES,IA 50011, USA. NR 65 TC 10 Z9 10 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 NOV 1 PY 1992 VL 46 IS 18 BP 11928 EP 11934 DI 10.1103/PhysRevB.46.11928 PG 7 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900078 ER PT J AU WANG, YJ NEWTON, MD DAVENPORT, JW AF WANG, YJ NEWTON, MD DAVENPORT, JW TI ELECTRONIC-STRUCTURE AND MAGNETIC COUPLING IN COPPER-OXIDE SUPERCONDUCTORS SO PHYSICAL REVIEW B LA English DT Review ID HIGH-TC SUPERCONDUCTORS; DIFFERENTIAL-OVERLAP TECHNIQUE; TRANSITION-METAL COMPLEXES; VALENCE BOND STATE; X-RAY-ABSORPTION; INTERMEDIATE NEGLECT; PAIRING INTERACTION; CHARGE-CARRIERS; LA2CUO4; CLUSTER AB The electronic structure and magnetic coupling in La2CUO4 and Nd2CUO4 have been analyzed using the results of all-valence-electron calculations for (Cu2O11)18-, (Cu4O12)16-, and (Cu4O20)32- clusters, and their p- and n-doped variants, embedded in a Madelung potential to represent the crystal environment. The calculations employ the semiempirical incomplete neglect of differential overlap (INDO) method, which is parametrized on the basis of atomic and molecular spectroscopic data, but which makes use of no data from copper oxide materials. The energies of the low-lying cluster spin states are fitted to a Heisenberg Hamiltonian and yield values of J (134 meV for La2CuO4 and 117 meV for Nd2CuO4) in close agreement with experiment. The evaluation of J can be compactly represented in terms of the parameters (t, U, and V) of a one-band Hamiltonian that controls resonance among covalent and ionic valence-bond structures. The resonance mixing is achieved by configuration interaction (CI) among valence-band structures defined in terms of localized molecular orbitals (LMO's) obtained from self-consistent field (SCF) INDO calculations. P doping is found to involve strong hybridization of the 2psigma orbitals of the in-plane oxygen ions and the 3d(x2-y2) orbitals of the Cu ions, and the resulting holes are predominantly (approximately 60%) located in the 2psigma orbitals. The lowest-energy n-doped cluster states involve addition of electrons to the 4s/4p Cu atom manifolds. However, the separation of these states from low-spin (3d10) alternatives is uncertain because of apparent sensitivity to the representation of the crystal potential, as found by Martin. C1 BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP WANG, YJ (reprint author), SUNY STONY BROOK,DEPT PHYS,STONY BROOK,NY 11794, USA. NR 100 TC 19 Z9 19 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1992 VL 46 IS 18 BP 11935 EP 11951 DI 10.1103/PhysRevB.46.11935 PG 17 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900079 ER PT J AU MCCARTY, KF LIU, JZ JIA, YX SHELTON, RN RADOUSKY, HB AF MCCARTY, KF LIU, JZ JIA, YX SHELTON, RN RADOUSKY, HB TI TEMPERATURE-DEPENDENCE OF THE PHONON FREQUENCIES, LINEWIDTHS, AND RAMAN-CONTINUUM SCATTERING OF SINGLE-DOMAIN Y0.56PR0.44BA2CU3O7 SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TC SUPERCONDUCTORS; CRYSTAL YBA2CU3O7-DELTA; ACTIVE PHONONS; GAP; POLARIZATION; ANISOTROPY; MODES AB We report detailed Raman-scattering measurements from a single-domain crystal of composition Y0.56Pr0.44Ba2Cu3O7 (T(c) = 40 K). Through a polarization analysis, 13 of the 15 Raman-active phonons are unambiguously identified. The frequencies and linewidths of the five A(g) phonons are studied as a function of temperature. Unlike YBa2Cu3O7, there are no pronounced superconductivity-induced changes in phonon frequency and linewidth. At all temperatures, the B1g-like phonon at 320 cm-1 is intrinsically much broader than in YBa2Cu3O7. The linewidths of the 440- and 515-cm-1 phonons decrease sharply with cooling, to an extent that cannot be explained by the simplest model of anharmonic decay. We identify Raman-scattering continua for photons polarized both within and perpendicular to the CuO2 planes. Like YBa2Cu3O7, the CuO2-plane continuum interferes strongly with the phonon scattering at 130 cm-1. Unlike YBa2Cu3O7, the CuO2-plane continuum of Y0.56Pr0.44Ba2O7 has a low-frequency tail that disappears upon cooling. C1 UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP MCCARTY, KF (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. RI McCarty, Kevin/F-9368-2012 OI McCarty, Kevin/0000-0002-8601-079X NR 28 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 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1992 VL 46 IS 18 BP 11958 EP 11964 DI 10.1103/PhysRevB.46.11958 PG 7 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900081 ER PT J AU RADTKE, RJ ULLAH, S LEVIN, K NORMAN, MR AF RADTKE, RJ ULLAH, S LEVIN, K NORMAN, MR TI CONSTRAINTS ON SUPERCONDUCTING TRANSITION-TEMPERATURES IN THE CUPRATES - ANTIFERROMAGNETIC SPIN FLUCTUATIONS SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TC SUPERCONDUCTORS; OXIDE SUPERCONDUCTORS; ORGANIC SUPERCONDUCTIVITY; NORMAL-STATE; METALS; CONDUCTIVITY; YBA2CU3O6+X; HE-3; PHENOMENOLOGY; SCATTERING AB Recently, several authors have suggested that antiferromagnetic spin fluctuations provide the pairing mechanism in the high-temperature superconductors. In this paper, we discuss this spin-fluctuation mechanism in the Fermi-surface-restricted Eliashberg formalism using a dynamical susceptibility whose form is constrained by neutron-scattering data. For definiteness, we consider the YBa2Cu3O7-delta family of superconductors, which we model with a realistic model band structure. Furthermore, we choose the electron-spin fluctuation coupling constant lambda to yield agreement with low-frequency ac conductivity measurements. We find that spin-singlet pairing can occur only for B1 and A2 symmetries and that the former symmetry yields the higher critical temperature T(c). The T(c) associated with the B1 symmetry is large in the weak-coupling limit, but is greatly reduced when strong-coupling effects are included. Finally, we observe that even for anisotropic pairing schemes, transport data that constrain lambda provide stringent limits on the critical temperature. C1 UNIV CHICAGO,JAMES FRANCK INST,CHICAGO,IL 60637. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP RADTKE, RJ (reprint author), UNIV CHICAGO,DEPT PHYS,CHICAGO,IL 60637, USA. RI Norman, Michael/C-3644-2013 NR 66 TC 55 Z9 55 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 NOV 1 PY 1992 VL 46 IS 18 BP 11975 EP 11985 DI 10.1103/PhysRevB.46.11975 PG 11 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900083 ER PT J AU BENNAHMIAS, M OBRIEN, JC RADOUSKY, HB GOODWIN, TJ KLAVINS, P LINK, JM SMITH, CA SHELTON, RN AF BENNAHMIAS, M OBRIEN, JC RADOUSKY, HB GOODWIN, TJ KLAVINS, P LINK, JM SMITH, CA SHELTON, RN TI MAGNETIC, STRUCTURAL, AND RAMAN CHARACTERIZATION OF RBA2CU2NBO8(R=PR, LA, OR ND) SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TC SUPERCONDUCTORS; YBA2CU3O7-X; VALENCE; ORDER; PR AB PrBa2Cu2NbO8 (PrBCNO) is an insulator analogous to the PrBa2Cu3O7 system having a similar structure but with NbO2 planes replacing the CuO chains. Single-phase polycrystalline samples of RBCNO have been synthesized with R = La, Pr, or Nd. These materials were characterized using magnetization, thermal gravimetric analysis in different atmospheres, x-ray diffraction, and Raman spectroscopy. The PrBCNO samples show a signature in the magnetization of a magnetic ordering at 12 K. No such magnetic phase transition is observed down to 2 K in NdBa2Cu2NbO8. C1 UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616. RP BENNAHMIAS, M (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. RI Link, Jonathan/L-2560-2013 OI Link, Jonathan/0000-0002-1514-0650 NR 25 TC 28 Z9 28 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 NOV 1 PY 1992 VL 46 IS 18 BP 11986 EP 11992 DI 10.1103/PhysRevB.46.11986 PG 7 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900084 ER PT J AU CRESPI, VH HOU, JG XIANG, XD COHEN, ML ZETTL, A AF CRESPI, VH HOU, JG XIANG, XD COHEN, ML ZETTL, A TI ELECTRON-SCATTERING MECHANISMS IN SINGLE-CRYSTAL K3C60 SO PHYSICAL REVIEW B LA English DT Note ID SUPERCONDUCTING K3C60 AB The temperature-dependent resistivity of single-crystal K3C60 is studied from the point of view of electron-electron and electron-phonon scattering. The electron-phonon analysis suggests that conventional electron-phonon coupling would be sufficient to account for the superconductivity, with contributions to the coupling from both high-frequency intraball and low-frequency interball modes. The resistivity was also compared to a quadratic temperature dependence, suggestive of electron-electron scattering at anomalously high temperatures. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP CRESPI, VH (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Hou, Jianguo/G-5076-2010; Xiang, Xiaodong/A-9445-2012; Zettl, Alex/O-4925-2016; Xiang, Xiaodong/A-5936-2017; OI Zettl, Alex/0000-0001-6330-136X; Crespi, Vincent/0000-0003-3846-3193 NR 23 TC 61 Z9 62 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1992 VL 46 IS 18 BP 12064 EP 12067 DI 10.1103/PhysRevB.46.12064 PG 4 WC Physics, Condensed Matter SC Physics GA JX929 UT WOS:A1992JX92900103 ER PT J AU BURDE, J DELEPLANQUE, MA DIAMOND, RM MACCHIAVELLI, AO STEPHENS, FS BEAUSANG, CW AF BURDE, J DELEPLANQUE, MA DIAMOND, RM MACCHIAVELLI, AO STEPHENS, FS BEAUSANG, CW TI HIGH-SPIN STATES IN OS-179 SO PHYSICAL REVIEW C LA English DT Article ID BAND-CROSSING FREQUENCIES; ROTATIONAL BANDS; INTRINSIC STATES; NUCLEI; ALIGNMENT; MODEL AB The Sm-154(Si-30,5n)179Os reaction has been used to study rotational bands at high spin by means of extensive gamma-ray coincidence measurements. The new alpha= - 1/2 signature partner of the 1/2-[521] band has been found up to spin 31/2- and the previously known alpha= + 1/2 partner extended up to spin 45/2-. The alpha= - 1/2 and alpha= + 1/2 components of the previously known 7/2-[514] and the 9/2+[624] bands were extended up to spins 63/2-, 53/2- and 63/2+,61/2+, respectively. The two components of the newly found band 5/2-[512] have been established up to spins 59/2- and 65/2-. In addition, two other new bands were found, one of them with spins up to 61/2+ decays to the 9/2+[624] band. Configurations have been proposed by comparing the signature splittings and the B(M1)IB(E2) ratios with the theoretical predictions. The latter points to rather strong Coriolis interaction between the 5/2-[512] and 7/2-[514] bands. The first band crossing observed in nine out of the ten bands is most probably due to the alignment of a pair of i13/2 neutrons, on the basis of a comparison of experimental Routhians with the cranking shell model calculations. In the three positive-parity sequences and in the alpha= + 1/2 signature of the 5/2-[512] band, second band crossings are also observed that are suggested to be caused by an alignment of two h9/2 protons. C1 LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. COMIS NACL ENERGIA ATOM,RA-1429 BUENOS AIRES,DF,ARGENTINA. RP BURDE, J (reprint author), HEBREW UNIV JERUSALEM,RACAH INST PHYS,JERUSALEM,ISRAEL. NR 21 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 NOV PY 1992 VL 46 IS 5 BP 1642 EP 1655 DI 10.1103/PhysRevC.46.1642 PG 14 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200013 ER PT J AU KOZUB, RL BYBEE, CR HINDI, MM SHRINER, JF HOLZMANN, R JANSSENS, RVF KHOO, TL MA, WC DRIGERT, MW GARG, U KOLATA, JJ AF KOZUB, RL BYBEE, CR HINDI, MM SHRINER, JF HOLZMANN, R JANSSENS, RVF KHOO, TL MA, WC DRIGERT, MW GARG, U KOLATA, JJ TI YRAST DECAYS IN K-43 SO PHYSICAL REVIEW C LA English DT Article AB High-spin states in K-43 were studied using the Be-9(S-36,pngamma)K-43 reaction. Threefold (pgamma1gamma2) coincidence data and gamma-ray intensity ratios were used to establish a decay scheme and identify negative- and positive-parity yrast decay chains. The 15/2- yrast state is relatively poorly aligned prior to decay. Energies of positive-parity levels predicted by Johnstone are in good agreement with experiment. C1 ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556. RP KOZUB, RL (reprint author), TENNESSEE TECHNOL UNIV,DEPT PHYS,COOKEVILLE,TN 38505, USA. NR 10 TC 3 Z9 3 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 NOV PY 1992 VL 46 IS 5 BP 1671 EP 1676 DI 10.1103/PhysRevC.46.1671 PG 6 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200016 ER PT J AU PIEPER, SC WIRINGA, RB PANDHARIPANDE, VR AF PIEPER, SC WIRINGA, RB PANDHARIPANDE, VR TI VARIATIONAL CALCULATION OF THE GROUND-STATE OF O-16 SO PHYSICAL REVIEW C LA English DT Article ID NUCLEAR-MATTER; 3-NUCLEON INTERACTION; ELECTRON-SCATTERING; 4-BODY NUCLEI; ENERGY; 3-BODY AB We report variational calculations of the ground state of O-16 with realistic two- and three-nucleon interactions. The trial wave function is constructed from pair- and triplet-correlation operators acting on a product of single-particle determinants. These operators include central, spin, isospin, tensor, spin-orbit, and three-nucleon potential components. Expectation values are evaluated with a cluster expansion for the noncentral correlations; terms in the expansion are evaluated exactly using Monte Carlo integration. The optimal trial function is obtained by minimizing the energy through the four-body cluster level. Results are reported for the ground-state binding energy, nucleon density and momentum distributions, charge form factor, and longitudinal structure function. They are also compared with the available results for few-body nuclei and nuclear matter with the same interactions. C1 UNIV ILLINOIS,DEPT PHYS,URBANA,IL 61801. RP PIEPER, SC (reprint author), ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439, USA. RI Wiringa, Robert/M-4970-2015 NR 34 TC 190 Z9 190 U1 0 U2 2 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 NOV PY 1992 VL 46 IS 5 BP 1741 EP 1756 DI 10.1103/PhysRevC.46.1741 PG 16 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200025 ER PT J AU NIKOLAUS, BA HOCH, T MADLAND, DG AF NIKOLAUS, BA HOCH, T MADLAND, DG TI NUCLEAR GROUND-STATE PROPERTIES IN A RELATIVISTIC POINT COUPLING MODEL SO PHYSICAL REVIEW C LA English DT Article ID QUANTUM FIELD-THEORY; FINITE NUCLEI; SCATTERING AB We present initial results in the calculation of nuclear ground state properties in a relativistic Hartree approximation. Our model consists of Skyrme-type interactions in four-, six-, and eight-fermion point couplings in a manifestly nonrenormalizable Lagrangian, which also contains.derivative terms to simulate the finite ranges of the mesonic interactions. A self-consistent procedure has been developed to solve the model equations for several nuclei simultaneously by use of a generalized nonlinear least-squares adjustment algorithm. With this procedure we determine the nine coupling constants of our model so as to reproduce measured ground state binding energies, rms charge radii, and spin-orbit splittings of selected closed major shell and closed subshell nuclei in nondeformed regions. The coupling constants obtained in this way predict these same observables for a much larger set of closed shell spherical nuclei to good accuracy and also predict these quantities for similar nuclei far outside the valley of beta stability. Finally, they yield properties of saturated nuclear matter in agreement with recent relativistic mean meson field approaches. C1 TH DARMSTADT,INST KERNPHYS,W-6100 DARMSTADT,GERMANY. LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. NR 32 TC 148 Z9 151 U1 2 U2 4 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 NOV PY 1992 VL 46 IS 5 BP 1757 EP 1781 DI 10.1103/PhysRevC.46.1757 PG 25 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200026 ER PT J AU VONEIFF, D WEIGEL, MK AF VONEIFF, D WEIGEL, MK TI RELATIVISTIC THOMAS-FERMI CALCULATIONS OF FINITE NUCLEI INCLUDING QUANTUM CORRECTIONS SO PHYSICAL REVIEW C LA English DT Article ID SEMI-CLASSICAL APPROXIMATIONS; HARTREE-FOCK-APPROXIMATION; FIELD-THEORY; SEMICLASSICAL EXPANSIONS; MATTER; HAMILTONIANS; TEMPERATURES; POTENTIALS; SYSTEMS; STATE AB Relativistic Thomas-Fermi calculations for finite nuclei including quantum corrections up to second order in HBAR, i.e., Wigner-Kirkwood and exchange corrections, have been performed. A linear sigma-omega model is used, in case of exchange-corrected calculations extended by pi-nucleon and tensor rho-nucleon contributions. A detailed discussion of the outcome shows that the inclusion of quantum corrections improves the description of the nuclear surface and the classical forbidden region in comparison to the standard relativistic Thomas-Fermi model. Furthermore, special attention is devoted to the investigation of the spin-orbit interaction and the influence of the or-meson mass on nuclear properties. C1 UNIV MUNICH,SEKT PHYS,W-8000 MUNICH 2,GERMANY. LUDWIG MAXIMILIANS UNIV,SEKT PHYS,W-8046 GARCHING,GERMANY. RP VONEIFF, D (reprint author), LAWRENCE BERKELEY LAB,DIV NUCL SCI,MAILSTOP 70A-3307,BERKELEY,CA 94720, USA. NR 44 TC 17 Z9 17 U1 0 U2 3 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 NOV PY 1992 VL 46 IS 5 BP 1797 EP 1810 DI 10.1103/PhysRevC.46.1797 PG 14 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200029 ER PT J AU GIBBS, WR DEDONDER, JP AF GIBBS, WR DEDONDER, JP TI NEUTRON RADII OF THE CALCIUM ISOTOPES SO PHYSICAL REVIEW C LA English DT Article ID DOUBLE-CHARGE-EXCHANGE; ELASTIC ELECTRON-SCATTERING; OPTICAL POTENTIALS; NUCLEUS SCATTERING; SPHERICAL NUCLEI; CROSS-SECTIONS; LI-11; HALO; CA-40,CA-42,CA-44,CA-48; DISTRIBUTIONS AB We have analyzed pion scattering data to determine the proton and neutron radii of the calcium isotopes Ca-40, Ca-42, Ca-44, Ca-48 using model densities in which the neutron matter distributions are considered to have two components corresponding to core and valence neutrons. The proton radii determined agree with those obtained by electromagnetic means, The radii of the valence distributions show a monotonic decrease throughout the shell from approximately 4.9 fm in Ca-42 to approximately 4.4 fm in Ca-44 and approximately 4.2 fm in Ca-48, although this last case is only indicative. The large valence neutron radius of Ca-42 suggests that the ground state of this nucleus may have some characteristics of a bound dineutron orbiting a closed core. C1 LOS ALAMOS NATL LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. UNIV PARIS 07, PHYS NUCL LAB, F-75221 PARIS 05, FRANCE. INST PHYS NUCL, DIV PHYS THEOR, F-91406 ORSAY, FRANCE. RP GIBBS, WR (reprint author), NEW MEXICO STATE UNIV, DEPT PHYS, LAS CRUCES, NM 88003 USA. NR 45 TC 29 Z9 29 U1 0 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 NOV PY 1992 VL 46 IS 5 BP 1825 EP 1833 DI 10.1103/PhysRevC.46.1825 PG 9 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200032 ER PT J AU BOWMAN, DR MADER, CM PEASLEE, GF BAUER, W CARLIN, N DESOUZA, RT GELBKE, CK GONG, WG KIM, YD LISA, MA LYNCH, WG PHAIR, L TSANG, MB WILLIAMS, C COLONNA, N HANOLD, K MCMAHAN, MA WOZNIAK, GJ MORETTO, LG FRIEDMAN, WA AF BOWMAN, DR MADER, CM PEASLEE, GF BAUER, W CARLIN, N DESOUZA, RT GELBKE, CK GONG, WG KIM, YD LISA, MA LYNCH, WG PHAIR, L TSANG, MB WILLIAMS, C COLONNA, N HANOLD, K MCMAHAN, MA WOZNIAK, GJ MORETTO, LG FRIEDMAN, WA TI INTERMEDIATE MASS FRAGMENT EMISSION AS A PROBE OF NUCLEAR-DYNAMICS SO PHYSICAL REVIEW C LA English DT Article ID HEAVY-ION COLLISIONS; LARGE-ANGLE CORRELATIONS; GAS PHASE-TRANSITION; MULTIFRAGMENT EMISSION; STATISTICAL MULTIFRAGMENTATION; PARTICLE-EMISSION; HOT NUCLEI; COMPLEX FRAGMENTS; SEQUENTIAL DECAY; MODEL AB Element distributions and fragment multiplicity distributions have been measured for E/A = 50 MeV Xe-129+C-12, Al-27, V-51, (nat)Cu, Y-89, and Au-197 reactions using a low threshold 4pi detector. Both distributions show a strong correlation with the detected charged particle multiplicity and a large degree of target independence. The measured distributions are compared with hybrid model calculations which incorporate important dynamical aspects in both the preequilibrium and statistical emission phases. Results of these calculations are in reasonable agreement with the data. However, uncertainties with regard to the compressibility of nuclear matter remain due to uncertainties in the coupling of the two models. C1 MICHIGAN STATE UNIV,DEPT PHYS & ASTRON,E LANSING,MI 48824. LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV ACCELERATOR & FUS RES,BERKELEY,CA 94720. UNIV WISCONSIN,DEPT PHYS,MADISON,WI 53706. RP BOWMAN, DR (reprint author), MICHIGAN STATE UNIV,NATL SUPERCONDUCTING LAB,E LANSING,MI 48824, USA. RI Carlin Filho, Nelson/C-2187-2012; Lynch, William/I-1447-2013; deSouza, Romualdo/P-5862-2015 OI Lynch, William/0000-0003-4503-176X; deSouza, Romualdo/0000-0001-5835-677X NR 77 TC 77 Z9 77 U1 1 U2 3 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 NOV PY 1992 VL 46 IS 5 BP 1834 EP 1848 DI 10.1103/PhysRevC.46.1834 PG 15 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200033 ER PT J AU HAMILTON, TM GREGORICH, KE LEE, DM CZERWINSKI, KR HANNINK, NJ KACHER, CD KADKHODAYAN, B KREEK, SA NURMIA, MJ LANE, MR NEU, MP TURLER, A HOFFMAN, DC AF HAMILTON, TM GREGORICH, KE LEE, DM CZERWINSKI, KR HANNINK, NJ KACHER, CD KADKHODAYAN, B KREEK, SA NURMIA, MJ LANE, MR NEU, MP TURLER, A HOFFMAN, DC TI SPONTANEOUS FISSION PROPERTIES OF LR-259(103) SO PHYSICAL REVIEW C LA English DT Article AB We have measured the mass and kinetic-energy distributions of fragments from the spontaneous fission of Lr-259. The Lr-259 was produced via the Cm-248 (N-15,4n) reaction with a production cross section of 100 nb using 81-MeV projectiles. The kinetic energies and times of the alpha particles and coincident fission fragments were measured using our rotating wheel system. From these data the half-life, mass, and kinetic-energy distributions were derived. The total kinetic-energy (TKE) distribution appears to consist of a single component with a most probable pre-neutron-emission TKE of 215+/-3 MeV. The mass distribution is predominantly symmetric with a full width at half maximum of about 20 mass numbers. These results are consistent with trends observed for other trans-berkelium spontaneously fissioning isotopes. We determined the half-life to be 6.14+/-0.36 s by measuring its alpha decay and the observed spontaneous fission half-life was consistent with that value. An energy of 8.439+/-0.010 MeV was measured for the main alpha transition of Lr-259. We measured a spontaneous fission to alpha-decay ratio of 0.25+/-0.03 which results in a partial half-life for spontaneous fission of 31+/-4 s, if there are no other appreciable modes of decay. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RP HAMILTON, TM (reprint author), LAWRENCE BERKELEY LAB,DIV NUCL SCI,MS 70A-3307,BERKELEY,CA 94720, USA. RI Turler, Andreas/D-3913-2014 OI Turler, Andreas/0000-0002-4274-1056 NR 24 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 NOV PY 1992 VL 46 IS 5 BP 1873 EP 1879 DI 10.1103/PhysRevC.46.1873 PG 7 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200036 ER PT J AU LAYMON, CM NELSON, RO WENDER, SA NILSSON, LR AF LAYMON, CM NELSON, RO WENDER, SA NILSSON, LR TI ISOVECTOR GIANT QUADRUPOLE-RESONANCE IN THE CA-40(N,GAMMA-0) REACTION SO PHYSICAL REVIEW C LA English DT Article ID PION CHARGE-EXCHANGE; E2 RESONANCE; EXCITATION; CALCIUM AB The fore-aft asymmetry and the 90-degrees differential cross section in the Ca-40(n,gamma0) reaction were measured from E(n) = 8 to 44 MeV. An energy-dependent asymmetry is observed that is interpreted as the result of the isovector giant quadrupole resonance interfering with background E1 amplitudes. The present data agree with previous low-energy data. At higher incident neutron energies, the present data do not agree with the predictions of a direct-semidirect model calculation based on the low-energy data alone. Calculations using the pure resonance model are in agreement with the data. C1 SVEDBERG LAB,UPPSALA,SWEDEN. RP LAYMON, CM (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 33 TC 10 Z9 10 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD NOV PY 1992 VL 46 IS 5 BP 1880 EP 1886 DI 10.1103/PhysRevC.46.1880 PG 7 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200037 ER PT J AU WOOD, SA MATTHEWS, JL KINNEY, ER GRAM, PAM REBKA, GA ROBERTS, DA AF WOOD, SA MATTHEWS, JL KINNEY, ER GRAM, PAM REBKA, GA ROBERTS, DA TI SYSTEMATICS OF INCLUSIVE PION DOUBLE CHARGE-EXCHANGE IN THE DELTA-RESONANCE REGION SO PHYSICAL REVIEW C LA English DT Article ID NUCLEAR-REACTIONS; TETRANEUTRON; HE-4; SCATTERING; SEARCH; MESONS; O-16 AB A systematic study of inclusive pion double charge exchange is reported for nuclei between A = 16 and A = 208. The doubly differential cross sections for the A(pi+,pi-) and A(pi-,pi+) reactions in O-16, Ca-40, Rh-103, and Pb-208 were measured at incident energies between 120 and 270 MeV at three to five outgoing pion angles. Pion spectra were measured over the energy range from 10 MeV to the kinematic limit for double charge exchange. Integrating these spectra over outgoing pion energy generated angular distributions, and subsequently integrating these angular distributions generated total reaction cross sections. The shapes of the measured spectra are compared with those determined by the distribution of events in four-body phase space and with those predicted by a model in which the pion undergoes two sequential single charge exchanges on nucleons in a Fermi gas. The cross sections are compared with predictions of cascade calculations in which more than two interactions, including pion absorption and scattering without charge exchange, may occur. C1 MIT,DEPT PHYS,CAMBRIDGE,MA 02139. MIT,NUCL SCI LAB,CAMBRIDGE,MA 02139. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. UNIV WYOMING,DEPT PHYS,LARAMIE,WY 82071. NR 60 TC 22 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 NOV PY 1992 VL 46 IS 5 BP 1903 EP 1921 DI 10.1103/PhysRevC.46.1903 PG 19 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200039 ER PT J AU PRICE, PB BONETTI, R GUGLIELMETTI, A CHIESA, C MATHEOUD, R MIGLIORINO, C MOODY, KJ AF PRICE, PB BONETTI, R GUGLIELMETTI, A CHIESA, C MATHEOUD, R MIGLIORINO, C MOODY, KJ TI EMISSION OF F-23 AND NE-24 IN CLUSTER RADIOACTIVITY OF PA-231 SO PHYSICAL REVIEW C LA English DT Article ID HEAVY-NUCLEI; DECAY AB Using a track-recording phosphate glass detector with a standard deviation sigma(Z)=0.23 charge unit, we collected approximately 2100 tracks of energetic clusters emitted from Pa-231. Of these, 1348 survived cuts on energy, angle of incidence to the detectors, and chi2. All but one of them are consistent with Ne-24, and our measured branching ratio, B(Ne/alpha)=(13.4+/-1.7) X 10(-12), for an alpha-decay half-life for Pa-231 of 3.28 X 10(4) yr. This value of B is a factor of 2.2 greater than was determined by Tretyakova et al., who observed 252 Ne decays. We identify one event as F-23, the nucleus predicted by cluster emission models to have the second highest branching ratio for emission from Pa-231. This corresponds to a branching ratio B (Ne/F)=1347(-940)+6440, the 1sigmalimits being governed by inverse Poisson statistics. Published models predict lower values of B (Ne/F), ranging from 3 to 400. Our event, if its 4sigma deviation from Ne is regarded as sufficient evidence for F, would be the first example of emission of an odd-Z cluster in spontaneous cluster radioactivity. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV MILAN,IST FIS GEN APPLICATA,I-20122 MILAN,ITALY. IST NAZL FIS NUCL,MILAN,ITALY. LAWRENCE LIVERMORE NATL LAB,DIV NUCL CHEM,LIVERMORE,CA 94551. RP PRICE, PB (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. NR 22 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 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD NOV PY 1992 VL 46 IS 5 BP 1939 EP 1945 DI 10.1103/PhysRevC.46.1939 PG 7 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200042 ER PT J AU KUMAR, BS BLUMENTHAL, DJ GREENE, SV MITCHELL, JT BROMLEY, DA SHAPIRA, D DELCAMPO, JG RAY, A HINDI, MM AF KUMAR, BS BLUMENTHAL, DJ GREENE, SV MITCHELL, JT BROMLEY, DA SHAPIRA, D DELCAMPO, JG RAY, A HINDI, MM TI EVOLUTION TOWARDS EQUILIBRATION IN ORBITING INTERACTIONS SO PHYSICAL REVIEW C LA English DT Article ID BACK-ANGLE YIELDS; SUBBARRIER; SYSTEM; FUSION AB We have studied the evolution towards mass equilibration in Mg-24+O-16 orbiting interactions. Mg-24 beams of energies between 75 and 115 MeV were used to bombard targets of O-16. Targetlike particles were detected at forward angles to determine the yields from orbiting interactions. The ratio of the orbiting yields of C-12 and O-16 exit channels rises continuously with energy from values below unity to above. The data are interpreted as demonstrating a strong entrance channel dependence at low energies, and an evolution towards mass equilibration with increasing energy. C1 OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,JOINT INST HEAVY ION RES,OAK RIDGE,TN 37831. TENNESSEE TECHNOL UNIV,DEPT PHYS,COOKEVILLE,TN 38505. RP KUMAR, BS (reprint author), YALE UNIV,AW WRIGHT NUCL STRUCT LAB,NEW HAVEN,CT 06511, USA. NR 16 TC 7 Z9 7 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 NOV PY 1992 VL 46 IS 5 BP 1946 EP 1950 DI 10.1103/PhysRevC.46.1946 PG 5 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200043 ER PT J AU CHARITY, RJ BARRETO, J SOBOTKA, LG SARANTITES, DG STRACENER, DW CHBIHI, A NICOLIS, NG AUBLE, R BAKTASH, C BEENE, JR BERTRAND, F HALBERT, M HENSLEY, DC HOREN, DJ LUDEMANN, C THOENNESSEN, M VARNER, R AF CHARITY, RJ BARRETO, J SOBOTKA, LG SARANTITES, DG STRACENER, DW CHBIHI, A NICOLIS, NG AUBLE, R BAKTASH, C BEENE, JR BERTRAND, F HALBERT, M HENSLEY, DC HOREN, DJ LUDEMANN, C THOENNESSEN, M VARNER, R TI MECHANISM FOR THE DISASSEMBLY OF EXCITED O-16 PROJECTILES INTO 4 ALPHA-PARTICLES SO PHYSICAL REVIEW C LA English DT Article ID HEAVY-ION REACTIONS; 32.5 MEV NUCLEON; ENERGY-LEVELS; LIGHT-NUCLEI; COLLISIONS; EMISSION; MODELS AB The decay of excited O-16 projectiles into the four alpha particle exit channel has been investigated. The projectiles, with bombarding energies of E/A = 25 MeV, were excited through peripheral interactions with Tb-159 target nuclei. A 4pi counter was used to detect both the projectile alpha particles and the light charged particles evaporated from the target nucleus. Criteria for selecting true O-16-->4alpha events with the minimum contamination from incorrectly identified events were examined. The distribution of relative angles between the four alpha particles in their center of mass frame was compared to simulations of O-16 decay by sequential decay mechanisms. The relative angles were shown to be consistent with a sequential evaporation mechanism if a nonzero angular momentum is assumed for the excited projectile. The momentum distribution of the alpha particles in the reaction plane was examined and found to be anisotropic for high projectile excitation energies. This anisotropy was shown to be consistent with Coulomb interactions between the first emitted alpha particle and the target nucleus, which would indicate that the lifetime of the projectile is very short, on the order of 10(-22) s. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37830. RP CHARITY, RJ (reprint author), WASHINGTON UNIV,DEPT CHEM,ST LOUIS,MO 63130, USA. OI Charity, Robert/0000-0003-3020-4998 NR 27 TC 21 Z9 21 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD NOV PY 1992 VL 46 IS 5 BP 1951 EP 1967 DI 10.1103/PhysRevC.46.1951 PG 17 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200044 ER PT J AU ROSENZWEIG, DP AMANN, JF BOUDRIE, RL DOSS, KGR DRAKE, DM HALPERN, I KHANDAKER, MA NELSON, J STORM, DW TIEGER, DR WOOD, SA AF ROSENZWEIG, DP AMANN, JF BOUDRIE, RL DOSS, KGR DRAKE, DM HALPERN, I KHANDAKER, MA NELSON, J STORM, DW TIEGER, DR WOOD, SA TI COMPARISON OF INCLUSIVE INELASTIC-SCATTERING OF PI+ AND PI- FROM NUCLEI AT 100 MEV SO PHYSICAL REVIEW C LA English DT Article ID TRUE ABSORPTION; PIONS AB Inclusive inelastic scattering spectra from C, Ca, Sn, and Pb were measured for 100-MeV pions at a number of angles. The observed ratios of the pi- and pi+ total inelastic cross sections for the different targets are explained in terms of a simple model which is based on the assumption that the scattered pion has interacted with only one nucleon. This model also accounts for the ratio between normal and charge-exchange scattering cross sections at 100 MeV. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. SASKATCHEWAN ACCELERATOR LAB,SASKATOON 57N 0W0,SASKATCHEWAN,CANADA. MIT,BATES LINEAR ACCELERATOR CTR,MIDDLETON,MA 01949. RP ROSENZWEIG, DP (reprint author), UNIV WASHINGTON,DEPT PHYS,FM-15,SEATTLE,WA 98195, USA. NR 17 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD NOV PY 1992 VL 46 IS 5 BP 1968 EP 1973 DI 10.1103/PhysRevC.46.1968 PG 6 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200045 ER PT J AU CHADWICK, MB OBLOZINSKY, P AF CHADWICK, MB OBLOZINSKY, P TI PARTICLE-HOLE STATE DENSITIES WITH LINEAR MOMENTUM AND ANGULAR-DISTRIBUTIONS IN PREEQUILIBRIUM REACTIONS SO PHYSICAL REVIEW C LA English DT Article ID GENERALIZED EXCITON MODEL; MULTISTEP COMPOUND; CROSS-SECTIONS; EMISSION AB We present two methods for the calculation of state densities with linear-momentum. The first is exact, convoluting single-particle and hole densities in momentum space, and can be used for nuclear excitations with small numbers of particles and holes. The second, based on statistical arguments, is applicable for excitations of many particles and holes and leads to state densities with a Gaussian linear-momentum dependence. Together, these two techniques allow state densities with linear momentum to be determined for any particle-hole excitation. The relationship between linear- and angular-momentum state densities is discussed, and we show how the familiar Gaussian angular-momentum distribution of states can be obtained from state densities with linear momentum. We argue that these state densities provide the most elegant and straightforward means for obtaining angular distributions in semiclassical preequilibrium theories, avoiding inconsistencies inherent in the commonly adopted procedure of using a nucleon-nucleon scattering kernel. In our approach the angular distribution of preequilibrium particles emitted from a two-particle-one-hole state is identical to that found by Kikuchi and Kawai. Angular distributions from more complex particle-hole states do, however, differ from a convolution of Kikuchi-Kawai scattering kernels, since we do not make a leading-particle approximation. As an illustrative example of the use of the Gaussian form of state densities with linear momentum, we calculate the angular distributions of emitted particles in the preequilibrium reaction Ho-165(alpha,p), E(alpha) = 109 MeV. Our calculations account for the experimental angular distributions well, even at large backward angles where many semiclassical approaches fail. C1 SLOVAK ACAD SCI,INST PHYS,CS-84228 BRATISLAVA,CZECHOSLOVAKIA. RP CHADWICK, MB (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 38 TC 23 Z9 23 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD NOV PY 1992 VL 46 IS 5 BP 2028 EP 2041 DI 10.1103/PhysRevC.46.2028 PG 14 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200053 ER PT J AU CUMMING, JB CHU, YY HAUSTEIN, PE AF CUMMING, JB CHU, YY HAUSTEIN, PE TI MOMENTUM-TRANSFER IN THE REACTIONS OF 13.6-GEV NUCLEON O-16 WITH COPPER SO PHYSICAL REVIEW C LA English DT Article ID RELATIVISTIC HEAVY-IONS; 300 GEV PROTONS; RECOIL PROPERTIES; C-12 IONS; 300-GEV PROTONS; ELECTROMAGNETIC DISSOCIATION; TARGET FRAGMENTATION; 400-GEV PROTONS; 28-GEV PROTONS; CROSS-SECTION AB Mean ranges and forward-to-backward ratios have been determined by the thick-target, thick-catcher technique for fragments from the interaction of 13.6-GeV/nucleon O-16 with copper. Experimental data are analyzed in terms of a two-step model and results are discussed in the context of limiting fragmentation and factorization and the predictions of a simple model for momentum transfer. Momenta imparted in the initial interactions of 13.6-GeV/nucleon O-16 were inferred to be approximately 12% lower than those for fragmentation of Cu by high-energy protons. RP CUMMING, JB (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. RI Cumming, James/I-3358-2013 OI Cumming, James/0000-0001-6930-0958 NR 38 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 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD NOV PY 1992 VL 46 IS 5 BP 2042 EP 2046 DI 10.1103/PhysRevC.46.2042 PG 5 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200054 ER PT J AU BOLZ, J ORNIK, U WEINER, RM AF BOLZ, J ORNIK, U WEINER, RM TI RELATIVISTIC HYDRODYNAMICS OF PARTIALLY STOPPED BARYONIC MATTER SO PHYSICAL REVIEW C LA English DT Article ID PARTICLE-PRODUCTION; DENSE MATTER; COLLISIONS; MODEL; STATE; HOT AB Relativistic hydrodynamics including final-state interactions is used for a detailed description of the experimental data on particle spectra of sulphur-sulphur collisions at 200 A GeV from the N A 35 Collaboration. Under the assumption of thermalization of the entire detected baryonic matter it is found that a consistent reproduction of both pion and proton spectra requires strong stopping as an initial condition for the expanding fireball. The results from these calculations are then used to extract a transverse radius which includes also contributions from the decay of unstable particle resonances. Its value is found to be rapidity dependent within the range of 3-4 fm, which agrees with experimental results from Bose-Einstein correlations. In addition, the analysis of the strange particle distribution indicates chemical equilibrium for K0 and LAMBDA particles. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP BOLZ, J (reprint author), UNIV MARBURG,DEPT PHYS,W-3550 MARBURG,GERMANY. NR 23 TC 28 Z9 28 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 NOV PY 1992 VL 46 IS 5 BP 2047 EP 2056 DI 10.1103/PhysRevC.46.2047 PG 10 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200055 ER PT J AU HOLLENBERG, LCL ROBERTS, CD MCKELLAR, BHJ AF HOLLENBERG, LCL ROBERTS, CD MCKELLAR, BHJ TI 2 LOOP CALCULATION OF THE OMEGA-RHO MASS SPLITTING SO PHYSICAL REVIEW C LA English DT Article ID JONA-LASINIO MODEL; COLOR SYMMETRY MODEL; AXIAL-VECTOR MESONS; QUANTUM CHROMODYNAMICS; QCD; VACUUM; FIELDS; GENERATION; SOLITON AB A nonlocal Nambu-Jona-Lasinio model is used to calculate strong interaction contributions to the omega-rho mass splitting. We analyze the contributions of the rho-->pipi, omega-->rhopi, and omega-->pipipi self-energy diagrams and fully account for their momentum dependence. We determine that, of these, the rho-->pipi term dominates to the point where the other terms may be neglected. The meson loop expansion in this model is therefore seen to be rapidly convergent. The results of our calculation suggest some qualitative constraints on the confining part of the q-qBAR interaction in models of this type. C1 ARGONNE NATL LAB, DIV PHYS, ARGONNE, IL 60439 USA. RP HOLLENBERG, LCL (reprint author), UNIV MELBOURNE, HIGH ENERGY PHYS RES CTR, SCH PHYS, PARKVILLE, VIC 3052, AUSTRALIA. RI Hollenberg, Lloyd/B-2296-2010 NR 40 TC 46 Z9 46 U1 0 U2 0 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 NOV PY 1992 VL 46 IS 5 BP 2057 EP 2065 DI 10.1103/PhysRevC.46.2057 PG 9 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200056 ER PT J AU DEAN, DJ GYULASSY, M MULLER, B REMLER, EA STRAYER, MR UMAR, AS WU, JS AF DEAN, DJ GYULASSY, M MULLER, B REMLER, EA STRAYER, MR UMAR, AS WU, JS TI MULTIPARTICLE PRODUCTION IN LEPTON-NUCLEUS COLLISIONS AND RELATIVISTIC STRING MODELS SO PHYSICAL REVIEW C LA English DT Article ID SCATTERING; HADRONS; STATE AB Nuclear attenuation of the leading (x(f) > 0) hadron and the nuclear enhancement of target fragmentation (x(f) < 0) hadrons in lepton-nucleus reactions axe calculated via a (3+1)-dimensional string-parton model. A (1+1)-dimensional string model is used to investigate the dependence of rapidity distributions on the lepton energy loss, nu = 10-100 GeV, the atomic number, A = 1-200, the effective string tension, kappa = 0.5-2 GeV/fm, the string decay constant, tau0 = 0.5-2 fm/c, and the string flip cross section, sigma(lg) = 0-30 mb. The (3+1)-dimensional string-parton model includes inelastic final state cascading of produced hadrons in the nucleus. We show how the A dependence of hadronic production in lepton-nucleus collisions, especially in the x(f) < 0 region, may be used to extract information on quark propagation and hadronization in nuclei. C1 VANDERBILT UNIV, DEPT PHYS & ASTRON, NASHVILLE, TN 37235 USA. LAWRENCE BERKELEY LAB, DIV NUCL SCI, BERKELEY, CA 94720 USA. DUKE UNIV, DEPT PHYS, DURHAM, NC 27706 USA. COLL WILLIAM & MARY, DEPT PHYS, WILLIAMSBURG, VA 23185 USA. RP OAK RIDGE NATL LAB, CTR COMP INTENS PHYS, DIV PHYS, OAK RIDGE, TN 37831 USA. RI Umar, Ahmet/J-4125-2013; OI Umar, Ahmet/0000-0002-9267-5253; Dean, David/0000-0002-5688-703X NR 37 TC 13 Z9 13 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD NOV PY 1992 VL 46 IS 5 BP 2066 EP 2076 DI 10.1103/PhysRevC.46.2066 PG 11 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200057 ER PT J AU CHEN, BQ HEENEN, PH BONCHE, P WEISS, MS FLOCARD, H AF CHEN, BQ HEENEN, PH BONCHE, P WEISS, MS FLOCARD, H TI OBSERVATION OF IDENTICAL BANDS IN SUPERDEFORMED NUCLEI WITH THE CRANKED HARTREE-FOCK METHOD SO PHYSICAL REVIEW C LA English DT Note ID TRANSITION ENERGIES; YRAST LINE; STATES AB We describe identical, or twinned bands, within the cranked Hartree-Fock model, with a Skyrme effective interaction. We show that the filling of specific orbitals can lead to bands with deexcitation gamma-ray energies differing by at most 2 keV in nuclei differing by two mass units and over a range of angular momenta comparable to the experimental one. We show also that the continuous change of the mean field with angular momentum is a key ingredient for twinning. C1 UNIV LIBRE BRUXELLES,SERV PHYS NUCL THEOR,B-1050 BRUSSELS,BELGIUM. LAWRENCE LIVERMORE NATL LAB,DEPT PHYS,LIVERMORE,CA 94550. INST PHYS NUCL,DIV PHYS THEOR,F-91406 ORSAY,FRANCE. CENS,F-91191 GIF SUR YVETTE,FRANCE. RP CHEN, BQ (reprint author), CALTECH,KELLOGG RADIAT LAB,PASADENA,CA 91125, USA. NR 23 TC 40 Z9 41 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 NOV PY 1992 VL 46 IS 5 BP R1582 EP R1586 PG 5 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200004 ER PT J AU JOHNSTON, K HUNGERFORD, EV KISHIMOTO, T MAYES, BW TANG, LG BART, S CHRIEN, RE LEE, L PILE, PH SUTTER, R HICKS, K FUKUDA, T KRAUSS, R GILL, DR STEARNS, R SEYFARTH, H AF JOHNSTON, K HUNGERFORD, EV KISHIMOTO, T MAYES, BW TANG, LG BART, S CHRIEN, RE LEE, L PILE, PH SUTTER, R HICKS, K FUKUDA, T KRAUSS, R GILL, DR STEARNS, R SEYFARTH, H TI SEARCH FOR A STRANGENESS-1 DIBARYON BELOW THE SIGMA-N THRESHOLD SO PHYSICAL REVIEW C LA English DT Note ID PHYSICS AB An experimental search for a p-wave, strangeness -1 dibaryon (D(s)) was undertaken at the Brookhaven Alternating Gradient Synchrotron using, for the first time, the He-3(K-, pi+)D(s)n reaction at 870 MeV/c. This dibaryon is predicted to be a spin singlet resonance lying below the SIGMAN threshold. In the region between LAMBDAN and SIGMAN thresholds there is significant LAMBDA production through two-step reactions and through virtual SIGMA production with subsequent conversion to a LAMBDA. At an experimental sensitivity (statistical, at the 2 sigma confidence level) of about 1.0 mub/sr, we find no evidence for a dibaryon in a region between the LAMBDA-N and SIGMA-N masses. C1 BROOKHAVEN NATL LAB, UPTON, NY 11973 USA. OHIO UNIV, ATHENS, OH 45701 USA. OSAKA UNIV, OSAKA, JAPAN. TEXAS A&M UNIV SYST, COLL STN, TX 77843 USA. TRIUMF, VANCOUVER, BC, CANADA. VASSAR COLL, POUGHKEEPSIE, NY 12601 USA. FORSCHUNGSZENTRUM JULICH, W-5170 JULICH 1, GERMANY. RP JOHNSTON, K (reprint author), UNIV HOUSTON, HOUSTON, TX 77204 USA. NR 19 TC 4 Z9 4 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD NOV PY 1992 VL 46 IS 5 BP R1573 EP R1576 PG 4 WC Physics, Nuclear SC Physics GA JX832 UT WOS:A1992JX83200002 ER PT J AU WIENCKE, LR CHURCH, MD GOTTSCHALK, EE HYLTON, RA KNAPP, BC SIPPACH, W STERN, BJ HARTOUNI, EP JENSEN, DA KLIMA, B KREISLER, MN RABIN, MSZ STRAIT, JB URIBE, J CHRISTIAN, DC GUTIERREZ, G HOLMES, SD WEHMANN, A AVILEZ, C FORBUSH, M HUSON, FR WHITE, JT AF WIENCKE, LR CHURCH, MD GOTTSCHALK, EE HYLTON, RA KNAPP, BC SIPPACH, W STERN, BJ HARTOUNI, EP JENSEN, DA KLIMA, B KREISLER, MN RABIN, MSZ STRAIT, JB URIBE, J CHRISTIAN, DC GUTIERREZ, G HOLMES, SD WEHMANN, A AVILEZ, C FORBUSH, M HUSON, FR WHITE, JT TI OBSERVATION OF COULOMB EFFECTS IN PRODUCTION OF PI+PI-,P-PI-, AND K+K- PAIRS IN PP COLLISIONS AT 27.5 GEV/C SO PHYSICAL REVIEW D LA English DT Article ID BOSE-EINSTEIN CORRELATIONS; HEAVY-ION COLLISIONS; INTERFEROMETRY AB In a study of collisions of 27.5 GeV/c protons in liquid hydrogen we have observed enhanced production of oppositely charged hadron pairs when the relative velocity of the two hadrons in the pair rest frame approaches alphac. The scale and velocity dependence of the enhancement agree well with the effect of the attractive Coulomb interaction as described by the Gamow factor. C1 UNIV GUANAJUATO,INST FIS,LEON,GUANAJUATO,MEXICO. TEXAS A&M UNIV SYST,DEPT PHYS,COLL STN,TX 77843. RP WIENCKE, LR (reprint author), FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. NR 16 TC 5 Z9 5 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 NOV 1 PY 1992 VL 46 IS 9 BP 3708 EP 3711 DI 10.1103/PhysRevD.46.3708 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX248 UT WOS:A1992JX24800004 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, R PRICE, LR 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, R PRICE, LR REINES, F SCHULTZ, J SOBEL, HW STONE, JL SULAK, LR SVOBODA, R TI ELECTRON-NEUTRINO AND MUON-NEUTRINO CONTENT OF THE ATMOSPHERIC FLUX SO PHYSICAL REVIEW D LA English DT Article AB Neutrino interactions from a 7.7 kton yr exposure of the IMB-3 detector are analyzed. A total of 935 contained events radiating over approximately 50 MeV of Cerenkov-equivalent energy and consistent with atmospheric neutrino interactions are identified. Of these, 610 have a single Cerenkov ring. Single-ring interactions are efficiently separated into those containing a showering particle (produced mainly by nu(e)) and those containing a nonshowering particle (produced mainly by nu(mu)). In the momentum range 100 < p(e) < 1500 MeV/c and 300 < p(mu) < 1500 MeV/c, the fraction of nonshowering events is 0.36+/-0.02(stat)+/-0.02(syst). Based on detailed models of neutrino production and interaction, a fraction of 0.51+/-0.01(stat)+/-0.05(syst) is expected. This deficit of nonshowering, or excess of showering, events relative to the total is supported by an independent analysis of muon decay signals. In the same sample 33+/-2(stat)% of events are accompanied by one or more muon decays, while 43+/-1(stat)% are expected. Further studies that could reduce systematic errors and discover the cause of these discrepancies are suggested. C1 UNIV MARYLAND,COLL PK,MD 20742. BOSTON UNIV,BOSTON,MA 02215. BROOKHAVEN NATL LAB,UPTON,NY 11973. CLEVELAND STATE UNIV,CLEVELAND,OH 44115. UNIV CALIF IRVINE,IRVINE,CA 92717. LOUISIANA STATE UNIV,BATON ROUGE,LA 70803. UNIV NOTRE DAME,NOTRE DAME,IN 46556. UNIV WARSAW,PL-00325 WARSAW,POLAND. RP BECKERSZENDY, R (reprint author), UNIV HAWAII,HONOLULU,HI 96822, USA. RI Sobel, Henry/A-4369-2011 NR 15 TC 545 Z9 545 U1 2 U2 4 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 NOV 1 PY 1992 VL 46 IS 9 BP 3720 EP 3724 DI 10.1103/PhysRevD.46.3720 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX248 UT WOS:A1992JX24800006 ER PT J AU RIZZO, TG AF RIZZO, TG TI NEW PROBES FOR EXTENDED GAUGE STRUCTURES AT THE DESY EP COLLIDER HERA SO PHYSICAL REVIEW D LA English DT Article ID LEFT-RIGHT MODEL; STANDARD MODEL; COLLISIONS; BOSONS; PHENOMENOLOGY; LEPTOQUARKS; SEARCH AB Doncheski and Hewett have recently shown that the ratio of neutral current to charged current cross sections, R = sigma(NC)/sigma(CC), can provide a more sensitive probe for the existence of heavy leptoquarks at the DESY ep collider HERA than the usual procedure which makes use of neutral current asymmetries. The apparent reason for this is that the standard model expectations for both of these cross sections are modified by the existence of such particles in a semicoherent manner. In this paper we apply this technique to extended electroweak models whose spectrum contains both a W' and a Z'. We find that measurements of R can, for some models, substantially increase the HERA search range for new gauge bosons beyond that which can be probed using the more conventional asymmetries. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. RP RIZZO, TG (reprint author), ARGONNE NATL LAB,DIV HIGH ENERGY PHYS,ARGONNE,IL 60439, USA. NR 40 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 1992 VL 46 IS 9 BP 3751 EP 3756 DI 10.1103/PhysRevD.46.3751 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX248 UT WOS:A1992JX24800009 ER PT J AU ELLIS, RK PARKE, S AF ELLIS, RK PARKE, S TI TOP-QUARK PRODUCTION BY W-GLUON FUSION SO PHYSICAL REVIEW D LA English DT Article ID HADRONIC COLLISIONS; QCD CORRECTIONS; HEAVY QUARKS; APPROXIMATION AB We present formulas and results on top-quark production by W-gluon fusion. A detailed comparison is made between the rate for this process and the backgrounds at the Fermilab Tevatron. The main backgrounds to this process come from ttBAR production and from the production of a W-boson plus jets in QCD. Using standard cuts at the Tevatron and a b-quark tag we find that the tbBAR production rate is smaller than at least one of these backgrounds for all top-quark masses accessible at Fermilab. RP ELLIS, RK (reprint author), FERMI NATL ACCELERATOR LAB,POB 500,BATAVIA,IL 60510, USA. NR 13 TC 91 Z9 91 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 NOV 1 PY 1992 VL 46 IS 9 BP 3785 EP 3788 DI 10.1103/PhysRevD.46.3785 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX248 UT WOS:A1992JX24800013 ER PT J AU ATKINSON, D HARADA, M SANDA, AI AF ATKINSON, D HARADA, M SANDA, AI TI IS THERE A P-WAVE BOUND-STATE OF W(L)W(L) - ON THE DYNAMIC GENERATION OF A RHO-MESON IN THE SIGMA-MODEL SO PHYSICAL REVIEW D LA English DT Article ID RADIATIVE-CORRECTIONS; HIGGS; BOSON; MASS; SCATTERING; SYMMETRY; SECTOR AB We investigate the possibility that the Higgs Lagrangian predicts the existence of a P-wave W(L)W(L) resonance. This problem is equivalent to studying the formation of the rho meson by the dynamics contained in the sigma model. Using the Pade approximation, Basdevant and Lee had claimed that rho is generated dynamically. We show that their result, while computationally correct, is not significant, because of the position of the Landau ghost. For the same reason, a W(L)W(L) P-wave resonance below 2 TeV is not expected, unless the standard model is violated. C1 INST THEORET PHYS,9700 AV GRONINGEN,NETHERLANDS. NAGOYA UNIV,DEPT PHYS,NAGOYA 46401,JAPAN. SUPERCONDUCTING SUPER COLLIDER LAB,DALLAS,TX 75237. ROCKEFELLER UNIV,DEPT PHYS,NEW YORK,NY 10021. RP ATKINSON, D (reprint author), FERMI NATL ACCELERATOR LAB,POB 500,BATAVIA,IL 60510, USA. NR 18 TC 24 Z9 24 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 1992 VL 46 IS 9 BP 3884 EP 3893 DI 10.1103/PhysRevD.46.3884 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX248 UT WOS:A1992JX24800027 ER PT J AU RIZZO, TG AF RIZZO, TG TI CONTRIBUTIONS TO THE W-BOSON ANOMALOUS MOMENTS IN THE 2-HIGGS-DOUBLET MODEL AT COLLIDER ENERGIES SO PHYSICAL REVIEW D LA English DT Article ID LIGHTEST HIGGS BOSON; RADIATIVE-CORRECTIONS; SUPERSYMMETRIC HIGGS; STANDARD MODEL; TOP QUARK; QUADRUPOLE-MOMENTS; E+E ANNIHILATION; MASS; E+E-->W+W; SECTOR AB We examine the one-loop contributions arising in the two-Higgs-doublet model to the W-boson anomalous magnetic dipole and electric quadrupole form factors for both photon and Z couplings relevant at collider energies. While the model parameter and q2 dependencies of these form factors are found to be significant, the corresponding size of these corrections are relatively small in comparison to unity. They are, however, found to be comparable in magnitude to the usual standard model loop corrections. Radiative corrections to the Higgs-particle masses and couplings due to heavy top quarks are included in the analysis. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. RP RIZZO, TG (reprint author), ARGONNE NATL LAB,DIV HIGH ENERGY PHYS,ARGONNE,IL 60439, USA. NR 71 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 1992 VL 46 IS 9 BP 3894 EP 3902 DI 10.1103/PhysRevD.46.3894 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX248 UT WOS:A1992JX24800028 ER PT J AU NEUBERT, M AF NEUBERT, M TI SUBLEADING ISGUR-WISE FORM-FACTORS FROM QCD SUM-RULES SO PHYSICAL REVIEW D LA English DT Article ID EFFECTIVE FIELD-THEORY; QUARK EFFECTIVE THEORY; HEAVY QUARKS; SEMILEPTONIC DECAYS; RESONANCE PHYSICS; STATIC QUARK; MESON; LATTICE; LIGHT; RENORMALIZATION AB In the heavy-quark effective theory, current matrix elements between two heavy pseudoscalar or vector mesons are parametrized by a set of universal form factors. These functions are calculated to subleading order in the 1/m(Q) expansion using QCD sum rules. The equations of motion and Ward identities of the effective theory axe incorporated in the analysis. Within this approach, parameter-free predictions are obtained for all form factors at zero recoil. The results allow for an almost model-independent analysis of current-induced transitions between heavy mesons. As an application, the 1/m(c) and 1/m(b) corrections to the hadronic form factors describing semileptonic B --> D l nu and B --> D* l nu decays are computed. The possibility of extracting V(cb) from these processes is discussed, and the importance of a measurement of symmetry-violating effects in ratios of form factors is pointed out. RP NEUBERT, M (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 53 TC 77 Z9 77 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 NOV 1 PY 1992 VL 46 IS 9 BP 3914 EP 3928 DI 10.1103/PhysRevD.46.3914 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX248 UT WOS:A1992JX24800030 ER PT J AU JAIN, P SOMMERER, AJ MCKAY, DW SPENCE, JR VARY, JP YOUNG, BL AF JAIN, P SOMMERER, AJ MCKAY, DW SPENCE, JR VARY, JP YOUNG, BL TI STRONG HIGGS BINDING OF HEAVY-FERMION SYSTEMS SO PHYSICAL REVIEW D LA English DT Article ID DYNAMICAL SYMMETRY BREAKING; BETHE-SALPETER-EQUATION; BOUND-STATE; EXCHANGE; MASSES; MODEL; QUARKS; BOSON AB We study the fermion-antifermion bound-state spectrum for heavy quarks and leptons by including the effect of Higgs-boson exchange. We use the Bethe-Salpeter equation in the ladder approximation and the N/D method for our calculation. The ladder Bethe-Salpeter equation is solved by using several well-known approximation schemes: the instantaneous approximation, the Blankenbecler-Sugar approximation, and covariant expansion in terms of Tschebeshev polynomials. Our results show that for quark-antiquark systems the Higgs-boson exchange generally dominates over QCD for quark masses larger than 500 GeV, and leads to very deep binding for quark masses in the TeV region. In the absence of the QCD force, as is the case with leptons, we determine the minimum value of the fermion mass needed to form a bound state as a function of the Higgs-boson mass. We further find that tightly bound states where the bound-state masses drop to zero appear for fermion masses between 1 and 1.8 TeV for all the approximations to the Bethe-Salpeter equation that we employed. The N/D method also leads to tightly bound states for fermion masses larger than about 1 TeV but does not in general yield zero-mass bound states. The meaning of the tightly bound states is discussed. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. RP JAIN, P (reprint author), UNIV KANSAS,DEPT PHYS & ASTRON,LAWRENCE,KS 66045, USA. NR 46 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 1992 VL 46 IS 9 BP 4029 EP 4042 DI 10.1103/PhysRevD.46.4029 PG 14 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX248 UT WOS:A1992JX24800040 ER PT J AU BODWIN, GT BRAATEN, E YUAN, TC LEPAGE, GP AF BODWIN, GT BRAATEN, E YUAN, TC LEPAGE, GP TI P-WAVE CHARMONIUM PRODUCTION IN B-MESON DECAYS SO PHYSICAL REVIEW D LA English DT Note ID QCD CORRECTIONS; QUARKONIUM DECAYS; WEAK DECAYS; REGULARIZATION; STATES AB We calculate the decay rates of B mesons into P-wave charmonium states using new factorization formulas that are valid to leading order in the relative velocity of the charmed quark and antiquark and to all orders in the running coupling constant of QCD. We express the production rates for all four P states in terms of two nonperturbative parameters: the derivative of the wave function at the origin and another parameter related to the probability for a charmed-quark-antiquark pair in a color-octet S-wave state to radiate a soft gluon and form a P-wave bound state. Using existing data on B meson decays into chi(c1) to estimate the color-octet parameter, we find that the color-octet mechanism may account for a significant-fraction of the chi(c1) production rate and that B mesons should decay into chi(c2) at a similar rate. C1 NORTHWESTERN UNIV,DEPT PHYS & ASTRON,EVANSTON,IL 60208. CORNELL UNIV,NEWMAN LAB NUCL STUDIES,ITHACA,NY 14853. RP BODWIN, GT (reprint author), ARGONNE NATL LAB,DIV HIGH ENERGY PHYS,ARGONNE,IL 60439, USA. NR 24 TC 96 Z9 96 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 NOV 1 PY 1992 VL 46 IS 9 BP R3703 EP R3707 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JX248 UT WOS:A1992JX24800003 ER PT J AU LAZARUS, EA LAO, LL OSBORNE, TH TAYLOR, TS TURNBULL, AD CHU, MS KELLMAN, AG STRAIT, EJ FERRON, JR GROEBNER, RJ HEIDBRINK, WW CARLSTROM, T HELTON, FJ HSIEH, CL LIPPMANN, S SCHISSEL, D SNIDER, R WROBLEWSKI, D AF LAZARUS, EA LAO, LL OSBORNE, TH TAYLOR, TS TURNBULL, AD CHU, MS KELLMAN, AG STRAIT, EJ FERRON, JR GROEBNER, RJ HEIDBRINK, WW CARLSTROM, T HELTON, FJ HSIEH, CL LIPPMANN, S SCHISSEL, D SNIDER, R WROBLEWSKI, D TI AN OPTIMIZATION OF BETA IN THE DIII-D TOKAMAK SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID ADVANCED TOROIDAL FACILITY; DOUBLET-III TOKAMAK; SAWTOOTH OSCILLATIONS; BALLOONING MODES; CURRENT PROFILES; STABILITY; PLASMAS; CONFINEMENT; EQUILIBRIUM; DISCHARGES AB Accurate equilibrium reconstruction and detailed stability analysis of a strongly shaped, double-null, beta(T) = 11% discharge shows that the plasma core is in the second stable regime to ideal ballooning modes. The equilibrium reconstruction using all the available data (coil currents, poloidal magnetic loops, motional Stark effect data, the kinetic pressure profile, the magnetic axis location, and the location of the two q = 1 surfaces) shows a region of negative magnetic shear near the magnetic axis, an outer positive shear region, and a low shear region connecting the two. The inner negative shear region allows a large positive shear region near the boundary, even at low q (q95 = 2.6), permitting a large outer region pressure gradient to be first regime stable. The inner region is in the second stable regime, consistent with the observed axial beta [beta(T)(0) = 44%]. In the low shear region p' vanishes, consistent with Mercier stability. This is one way to extend the ballooning limit in shaped plasmas while maintaining stability against external kinks. The n = 1 analysis shows that the plasma is unstable to an ideal internal mode, consistent with the experimental observations of a saturated internal m/n = 1/1 mode. The core plasma pressure, not being limited by ballooning stability, appears to be reaching a local equilibrium limit at the magnetic axis. C1 UNIV CALIF IRVINE,IRVINE,CA 92717. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP LAZARUS, EA (reprint author), GEN ATOM,POB 85608,SAN DIEGO,CA 92186, USA. NR 45 TC 76 Z9 76 U1 0 U2 3 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 NOV PY 1992 VL 4 IS 11 BP 3644 EP 3662 DI 10.1063/1.860373 PG 19 WC Physics, Fluids & Plasmas SC Physics GA JW336 UT WOS:A1992JW33600019 ER PT J AU SHEEHEY, P HAMMEL, JE LINDEMUTH, IR SCUDDER, DW SHLACHTER, JS LOVBERG, RH RILEY, RA AF SHEEHEY, P HAMMEL, JE LINDEMUTH, IR SCUDDER, DW SHLACHTER, JS LOVBERG, RH RILEY, RA TI 2-DIMENSIONAL DIRECT SIMULATION OF DEUTERIUM-FIBER-INITIATED Z-PINCHES WITH DETAILED COMPARISON TO EXPERIMENT SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID ENERGY-BALANCE; STABILITY; INSTABILITY; ABLATION AB Deuterium-fiber-initiated Z-pinch experiments have been simulated using a two-dimensional resistive magnetohydrodynamic model, which includes many important experimental details, such as "cold-start" initial conditions, thermal conduction, radiation, actual discharge current versus time, and grids of sufficient size and resolution to allow realistic development of the plasma. When the fiber becomes fully ionized (at a time depending on current ramp and fiber thickness), the simulations show rapidly developing m = 0 instabilities, which originated in the corona surrounding the fiber, drive intense nonuniform heating and rapid expansion of the plasma column. Diagnostics generated from the simulation results, such as shadowgrams and interferograms, are in good agreement with experiment. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. UNIV CALIF SAN DIEGO, DEPT PHYS, LA JOLLA, CA 92093 USA. RP SHEEHEY, P (reprint author), UNIV CALIF LOS ANGELES, DEPT PHYS, LOS ANGELES, CA 90024 USA. NR 42 TC 26 Z9 26 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD NOV PY 1992 VL 4 IS 11 BP 3698 EP 3706 DI 10.1063/1.860325 PG 9 WC Physics, Fluids & Plasmas SC Physics GA JW336 UT WOS:A1992JW33600023 ER PT J AU DURST, RD FONCK, RJ WONG, KL CHENG, CZ FREDRICKSON, ED PAUL, SF AF DURST, RD FONCK, RJ WONG, KL CHENG, CZ FREDRICKSON, ED PAUL, SF TI MEASUREMENTS OF THE RADIAL STRUCTURE AND POLOIDAL SPECTRA OF TOROIDAL ALFVEN EIGENMODES IN THE TOKAMAK FUSION TEST REACTOR SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article AB Toroidal Alfven eigenmodes (TAE) have been excited by tangential neutral beam injection in the Tokamak Fusion Test Reactor (TFTR) [Proceedings of the Thirteenth International Conference on Plasma Physics and Controlled Nuclear Fusion Research, 1990, Washington, D.C. (International Atomic Energy Agency, Vienna, 1990), Vol. 1, p. 9]. Beam emission spectroscopy (BES) has been used to study the radial structure and the poloidal power spectra of these modes. Radial profiles show a global, standing wave structure with a node near r/a = 0.6 and a maximum displacement of about 5-10 mm. The cross-phase profiles and the power spectra both imply that the mode is composed of a mixture of components with various poloidal and toroidal mode numbers, as expected for the TAE. Measurements of the poloidal mode spectrum via BES show good agreement with theoretical simulations performed by a nonvariational, kinetic magnetohydrodynamics stability code (NOVA-K [Cheng, Phys. Rep. 211, 1 (1992)]). In particular, the dominant harmonics in the poloidal spectrum obey the expected relation m + 1/2 almost-equal-to q(r) n. C1 PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543. RP DURST, RD (reprint author), UNIV WISCONSIN,MADISON,WI 53706, USA. RI Cheng, Chio/K-1005-2014 NR 15 TC 30 Z9 30 U1 0 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 NOV PY 1992 VL 4 IS 11 BP 3707 EP 3712 DI 10.1063/1.860326 PG 6 WC Physics, Fluids & Plasmas SC Physics GA JW336 UT WOS:A1992JW33600024 ER PT J AU CHU, MS GREENE, JM LAO, LL TURNBULL, AD CHANCE, MS AF CHU, MS GREENE, JM LAO, LL TURNBULL, AD CHANCE, MS TI A NUMERICAL STUDY OF THE HIGH-N SHEAR ALFVEN SPECTRUM GAP AND THE HIGH-N GAP MODE SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID EIGENMODES; TOKAMAKS; EXCITATION AB The toroidicity-induced gaps of the shear Alfven wave spectrum in tokamaks are shown to satisfy an envelope equation. The structure of these gaps, and the location of the high-n gap modes, which are localized modes with frequency in the gap, are studied for general numerically generated equilibria. The dependence of the frequencies of the gaps and the gap modes on the equilibrium properties, such as elongation, triangularity, and beta of the plasma are explored. C1 PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543. RP CHU, MS (reprint author), GEN ATOM,SAN DIEGO,CA 92186, USA. NR 21 TC 116 Z9 116 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 NOV PY 1992 VL 4 IS 11 BP 3713 EP 3721 DI 10.1063/1.860327 PG 9 WC Physics, Fluids & Plasmas SC Physics GA JW336 UT WOS:A1992JW33600025 ER PT J AU FU, GY CHENG, CZ AF FU, GY CHENG, CZ TI EXCITATION OF HIGH-N TOROIDICITY-INDUCED SHEAR ALFVEN EIGENMODES BY ENERGETIC PARTICLES AND FUSION ALPHA-PARTICLES IN TOKAMAKS SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID INSTABILITIES; MODES; DESTABILIZATION; PLASMAS AB The stability of high-n toroidicity-induced shear Alfven eigenmodes (TAE) in the presence of fusion alpha particles or energetic ions in tokamaks is investigated. The TAE modes are discrete in nature, and thus can easily tap the free energy associated with energetic particle pressure gradient through wave particle resonant interaction. A quadratic form is derived for the high-n TAE modes using gyrokinetic equation. The kinetic effects of energetic particles are calculated perturbatively using the ideal magnetohydrodynamic (MHD) solution as the lowest-order eigenfunction. The finite Larmor radius (FLR) effects and the finite drift orbit width (FDW) effects are included for both circulating and trapped energetic particles. It is shown that, for circulating particles, FLR and FDW effects have two opposite influences on the stability of the high-n TAE modes. First, they have the usual stabilizing effects by reducing the wave particle interaction strength. Second, they also have destabilizing effects by allowing more particles to resonate with the TAE modes. It is found that the growth rate induced by the circulating alpha particles increases linearly with the toroidal mode number n for small k(thetarhoalpha), and decreases as 1/n for k(thetarhoalpha) much greater than 1. The maximum growth rate is obtained at k(thetarhoalpha) on the order of unity, and is nearly constant for the range of 0.7 < upsilon(alpha)/upsilon(A) < 2.5. On the other hand, the trapped particle response is dominated by the precessional drift resonance. The bounce resonant contribution is negligible. The growth rate peaks sharply at the value of k(thetarhoalpha), such that the precessional drift resonance occurs for the most energetic trapped particles. The maximum growth rate due to the energetic trapped particles is comparable to that of circulating particles. Finally, the effect of the two-dimensional wave structure of TAE modes is considered by using the Wentzel-Kramers-Brillouin (WKB) method. RP FU, GY (reprint author), PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. RI Cheng, Chio/K-1005-2014 NR 34 TC 88 Z9 88 U1 1 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 NOV PY 1992 VL 4 IS 11 BP 3722 EP 3734 DI 10.1063/1.860328 PG 13 WC Physics, Fluids & Plasmas SC Physics GA JW336 UT WOS:A1992JW33600026 ER PT J AU MAGELSSEN, GR BACH, DR EVANS, S FORSLUND, DW HOCKADAY, RG STUDEBAKER, JK AF MAGELSSEN, GR BACH, DR EVANS, S FORSLUND, DW HOCKADAY, RG STUDEBAKER, JK TI LONG PULSE X-RAY-EMISSION FROM LASER-IRRADIATED EXPLODING CYLINDERS SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID ABSORPTION; TARGETS; FUSION; MATTER AB A CO2 laser was used to irradiate hollow polystyrene cylinders along their axis. The laser-generated high-energy electrons appear to uniformly heat the cylinder throughout its volume and the cylinder explodes. The imploding and stagnation character of the exploding cylinder gives rise to a long x-ray pulse, much longer than the laser pulse, and to a peak emission that occurs after the laser pulse. The fast ions that are generated appear not to interact with the thermal plasma. Two-dimensional calculations that reproduce much of the experimental x-ray signature and observed hydrodynamic flow are presented. RP MAGELSSEN, GR (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0899-8221 J9 PHYS FLUIDS B-PLASMA PD NOV PY 1992 VL 4 IS 11 BP 3747 EP 3752 DI 10.1063/1.860474 PG 6 WC Physics, Fluids & Plasmas SC Physics GA JW336 UT WOS:A1992JW33600028 ER PT J AU CAMPBELL, EM AF CAMPBELL, EM TI THE PHYSICS OF MEGAJOULE, LARGE-SCALE, AND ULTRAFAST SHORT-SCALE LASER PLASMAS SO PHYSICS OF FLUIDS B-PLASMA PHYSICS LA English DT Article ID STIMULATED SCATTERING PROCESSES; CHIRPED-PULSE AMPLIFICATION; ND-GLASS LASER; PARAMETRIC-INSTABILITIES; INVERSE BREMSSTRAHLUNG; ELECTROMAGNETIC-WAVES; UNIFORM ILLUMINATION; COMPTON-SCATTERING; IRRADIATED PLASMAS; RAMAN-SCATTERING AB Recent advances in laser science and technology have opened new possibilities for the study of high energy density plasma physics. The advances include techniques to control the laser spatial and temporal coherence, and the development of laser architectures and optical materials that have led to the demonstration of compact, short pulse (tau < 10(-12) sec) high brightness lasers, capable of irradiating plasmas with intensities > 10(18) W/cm2. Experiments with reduced laser coherence have shown a substantial decrease in laser-driven parametric instabilities and have extended the parameter range where inverse bremsstrahlung absorption is the dominant coupling process. Beam smoothing with short wavelength lasers should result in inverse bremsstrahlung dominated coupling in the irradiance parameter regimes of the millimeter scale-length plasmas envisioned for the megajoule class lasers for ignition and gain in inertial fusion. In addition new regimes of laser-plasma coupling will become experimentally accessible when plasmas are irradiated with I > 10(18) W/CM2 . Relativistic effects, extreme profile modification, and electrons heated to energies exceeding 1 MeV are several of the phenomena that are expected. Numerous applications in basic and applied plasma physics will result from these new capabilities. RP CAMPBELL, EM (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 109 TC 39 Z9 39 U1 0 U2 6 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 NOV PY 1992 VL 4 IS 11 BP 3781 EP 3799 DI 10.1063/1.860333 PG 19 WC Physics, Fluids & Plasmas SC Physics GA JW336 UT WOS:A1992JW33600032 ER PT J AU NIAZI, M JOHNSON, LR AF NIAZI, M JOHNSON, LR TI Q IN THE INNER CORE SO PHYSICS OF THE EARTH AND PLANETARY INTERIORS LA English DT Article; Proceedings Paper CT SYMP OF THE INTERNATIONAL ASSOC OF SEISMOLOGY AND PHYSICS OF THE EARTHS INTERIOR - PHYSICAL PROPERTIES OF THE EARTHS INTERIOR : MANTLE TO CORE CY AUG 20-21, 1991 CL VIENNA, AUSTRIA SP INT ASSOC SEISMOL & PHYS EARTHS INTERIOR ID TIMES; EARTH AB Short-period vertical seismograms from ten earthquakes and one nuclear explosion in the distance range of 140-170 degrees are examined for a study of the anelastic properties of the inner core. The depth of the earthquake foci varies between 116 and 625 km. The phases of interest are PKP(BC branch) and PKIKP with bottoming depths in the upper few hundred kilometers of the inner core. The data consist of high-quality digital data at sampling rates 20/40 samples per second selected after an extensive search of the 1985 1986 GDSN event tapes for short-period P waves with a high signal-to-noise ratio. The results are based primarily upon observations between distances of 147-degrees and 154-degrees. Useful information regarding the attenuation characteristics of the region below the inner core boundary (ICB) can be obtained from the observed relative amplitude and frequency content of the PKIKP and PKP(BC) phases. We have used Fourier spectral ratios of PKIKP-PKP(BC) for the estimation of the attenuation along the inner core segment of the rav path. Because of the limited frequency band of the data, it is difficult to resolve any frequency dependence for Q. Within the depth range of 150-300 km below the inner core boundary, the data yield a maximum likelihood estimate of 175 for the mean estimate of Q(alpha), with no clear indication of depth dependence. RP NIAZI, M (reprint author), LAWRENCE BERKELEY LAB,CTR COMPUTAT SEISMOL,BERKELEY,CA 94720, USA. NR 17 TC 23 Z9 23 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-9201 J9 PHYS EARTH PLANET IN JI Phys. Earth Planet. Inter. PD NOV PY 1992 VL 74 IS 1-2 BP 55 EP 62 DI 10.1016/0031-9201(92)90067-6 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA KA569 UT WOS:A1992KA56900005 ER PT J AU LEE, TD PANG, Y AF LEE, TD PANG, Y TI NONTOPOLOGICAL SOLITONS SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID NON-TOPOLOGICAL SOLITONS; COLOR-DIELECTRIC MODEL; 3 SPACE-DIMENSIONS; EXTENDED-HADRON MODELS; QUANTUM FIELD-THEORY; BLACK-HOLES; BOSON STARS; BAG MODEL; MOMENTUM PROJECTION; NONPERTURBATIVE METHODS AB Nontopological solitons are stable bound state solutions whose boundary condition at infinity is the same as that for the physical vacuum state. They exist in classical, as well as quantum mechanical, field theories. These solutions in any space-dimension are reviewed. We also discuss their applications to Bose liquid, hadron structures and soliton stars. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RP LEE, TD (reprint author), COLUMBIA UNIV,NEW YORK,NY 10027, USA. NR 141 TC 281 Z9 286 U1 0 U2 7 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 NOV PY 1992 VL 221 IS 5-6 BP 251 EP 350 DI 10.1016/0370-1573(92)90064-7 PG 100 WC Physics, Multidisciplinary SC Physics GA KA484 UT WOS:A1992KA48400001 ER PT J AU KRESIN, VV AF KRESIN, VV TI COLLECTIVE RESONANCES AND RESPONSE PROPERTIES OF ELECTRONS IN METAL-CLUSTERS SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID SELF-CONSISTENT CALCULATION; JELLIUM-BACKGROUND MODEL; GIANT DIPOLE RESONANCE; SODIUM CLUSTERS; QUANTUM DOTS; OPTICAL-ABSORPTION; SHELL STRUCTURE; PLASMA-RESONANCE; SUM-RULES; PHOTOABSORPTION SPECTRA AB The delocalized valence electron cloud in metal clusters displays strong collective behavior. This fact is reflected in a variety of cluster properties, including photoabsorption resonances and electric polarizability. Experiments have demonstrated that the response properties of cluster electrons possess a number of features unique to the microscopic size regime. In this paper the experimental picture is considered, and a theoretical discussion of the size-dependent behavior of electrons in finite systems is presented. Topics discussed include collective resonance frequencies and oscillator strengths in spherical and deformed clusters, electron distribution, and static polarizability. The theoretical analysis presents a consistent picture of cluster spectra which reflects the unique properties of these systems and is successful in explaining the experimental data for a wide variety of metal clusters. Suggestions for further measurements are made, including the prediction of a new photoabsorption mode unique to small metallic clusters. 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 150 TC 143 Z9 143 U1 1 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 NOV PY 1992 VL 220 IS 1 BP 1 EP 52 DI 10.1016/0370-1573(92)90056-6 PG 52 WC Physics, Multidisciplinary SC Physics GA JY161 UT WOS:A1992JY16100001 ER PT J AU WEAVER, H AF WEAVER, H TI SILICON-CARBIDE PROMISES LONGER MEMORIES FOR THE FUTURE SO PHYSICS WORLD LA English DT Article RP WEAVER, H (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 0 TC 16 Z9 16 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-8585 J9 PHYS WORLD JI Phys. World PD NOV PY 1992 VL 5 IS 11 BP 22 EP 23 PG 2 WC Physics, Multidisciplinary SC Physics GA JY147 UT WOS:A1992JY14700020 ER PT J AU KOENRAADT, H SOMERVILLE, SC JONES, AL AF KOENRAADT, H SOMERVILLE, SC JONES, AL TI CHARACTERIZATION OF MUTATIONS IN THE BETA-TUBULIN GENE OF BENOMYL-RESISTANT FIELD STRAINS OF VENTURIA-INAEQUALIS AND OTHER PLANT PATHOGENIC FUNGI SO PHYTOPATHOLOGY LA English DT Article ID CORRELATED CROSS-RESISTANCE; BENZIMIDAZOLE-RESISTANT; ASPERGILLUS-NIDULANS; ISRAEL; PHENYLCARBAMATE; TRANSFORMATION; INHERITANCE; FRAGMENTS; SEQUENCE; CLONING AB All benomyl-resistant field strains of Venturia inaequalis, V. pirina, Monilinia fructicola, Sclerotinia homoeocarpa, and six species of Penicillium, except those with low resistance to benomyl, were found to contain a single base pair mutation in their beta-tubulin gene that resulted in an amino acid substitution in beta-tubulin. In V. inaequalis, codon 198, which encodes glutamic acid in a sensitive strain, was converted to a codon for alanine in a strain with very high resistance, to a codon for lysine in a strain with high resistance, or to a codon for glycine in a strain with medium resistance to benomyl. Codon 200 for phenylalanine was converted to a codon for tyrosine in a second strain of V. inaequalis with medium resistance to benomyl. Among field strains of other fungi, 14 had a glutamic acid to lysine, alanine, or valine substitution at position 198, and three had a phenylalanine to tyrosine substitution at position 200. Among seven benomyl-resistant strains with sensitivity to the N-phenylcarbamate fungicide diethofencarb, all had a glutamic acid to alanine or glycine substitution at position 198. A comparison of the codon changes in the beta-tubulin gene of field strains with laboratory-induced benomyl-resistant mutants of model fungi showed that mutations conferring field resistance represent a small subset of the mutations recovered in laboratory experiments. C1 MICHIGAN STATE UNIV,DEPT BOT & PLANT PATHOL,E LANSING,MI 48824. MICHIGAN STATE UNIV,PESTICIDE RES CTR,E LANSING,MI 48824. MICHIGAN STATE UNIV,DOE,PLANT RES LAB,E LANSING,MI 48824. NR 35 TC 164 Z9 182 U1 1 U2 13 PU AMER PHYTOPATHOLOGICAL SOC PI ST PAUL PA 3340 PILOT KNOB ROAD, ST PAUL, MN 55121 SN 0031-949X J9 PHYTOPATHOLOGY JI Phytopathology PD NOV PY 1992 VL 82 IS 11 BP 1348 EP 1354 DI 10.1094/Phyto-82-1348 PG 7 WC Plant Sciences SC Plant Sciences GA JW512 UT WOS:A1992JW51200016 ER PT J AU SERGEEV, VA ELPHIC, RC MOZER, FS SAINTMARC, A SAUVAUD, JA AF SERGEEV, VA ELPHIC, RC MOZER, FS SAINTMARC, A SAUVAUD, JA TI A 2-SATELLITE STUDY OF NIGHTSIDE FLUX-TRANSFER EVENTS IN THE PLASMA SHEET SO PLANETARY AND SPACE SCIENCE LA English DT Article ID ELECTRIC-FIELD; SUBSTORM EXPANSION; GEOMAGNETIC TAIL; ISEE SATELLITES; BOUNDARY-LAYER; MAGNETIC-FIELD; NEUTRAL SHEET; RECONNECTION; MAGNETOTAIL; MAGNETOSPHERE AB High time resolution measurements of magnetic and electric fields and of the kiloelectronvolt electron flux at X approximately -21 R(e) in the central magnetotail were used in the study of short-duration (time scale 1 min) magnetic field events during two consecutive substorms on 23 March 1979. These events were observed at ISEE-1 and 2 (having 0.3 R(e) separation along the Z-coordinate), both inside and outside of the thinned plasma sheet, close (in time) to the polarity reversal of the plasma flow from tailward to earthward direction in association with the transient plasma sheet expansions. The enhanced magnetic flux closure (southward B(z) during tailward streaming events, northward during earthward streaming events), plus enhanced plasma flow during these events, suggest that they are nightside magnetic flux transfer events (NFTEs). The typical behaviour of the magnetic field during a NFTE (compression, rotation then field decrease), the signatures of overpressure in such structures and their close correlation with ground-based observed auroral activations and high energy particle bursts signify that NFTE structures may result from the impulsive reconnection in the plasmasheet. Systematic differences in the magnetic variations found at ISEE-1 and 2 indicate current concentration at the outer plasmasheet boundary during the passage of a NFTE. Two NFTEs appeared to have structures similar to magnetic flux ropes. The NFTE structure and associated current system, as well as the interpretation of NFTE signatures in terms of the impulsive reconnection, are discussed. During the "poleward leap" stage of one substorm, the spacecraft within the central part of the plasma sheet observed the intense earthward magnetic flux transport associated with superimposed NFTE structures. The estimated amount of this flux transfer explained well the observed amplitude of the poleward expansion of the westward electrojet in the conjugate auroral zone. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. UNIV CALIF BERKELEY,SPACE SCI LAB,BERKELEY,CA 94720. UNIV TOULOUSE 1,CESR,CNRS,F-31042 TOULOUSE,FRANCE. RP SERGEEV, VA (reprint author), UNIV ST PETERSBURG,INST PHYS,ST PETERSBURG,USSR. RI Sergeev, Victor/H-1173-2013 OI Sergeev, Victor/0000-0002-4569-9631 NR 44 TC 84 Z9 86 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD NOV PY 1992 VL 40 IS 11 BP 1551 EP 1572 DI 10.1016/0032-0633(92)90052-P PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA KD193 UT WOS:A1992KD19300008 ER PT J AU VANTHOF, J LAMM, SS AF VANTHOF, J LAMM, SS TI SITE OF INITIATION OF REPLICATION OF THE RIBOSOMAL GENES OF PEA (PISUM-SATIVUM) DETECTED BY 2-DIMENSIONAL GEL-ELECTROPHORESIS SO PLANT MOLECULAR BIOLOGY LA English DT Article DE REPLICATION; ORIGIN; RDNA; 5-AMINOURACIL; PISUM-SATIVUM; SYNCHRONY ID RNA GENES; DNA; CEREVISIAE AB The time course of replication of the 9 kb ribosomal DNA repeats of synchronized root cells of pea was followed by two-dimensional gel electrophoresis. The temporal order of appearance of single-stranded replication intermediates shows that replication begins within the subrepeats located in the intergenic spacer region about 1.5 kb downstream from the 3' end of the 25S gene. Hybridization to specific probes indicated that this location is identical to that established earlier by a different method. RP VANTHOF, J (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. NR 21 TC 16 Z9 16 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0167-4412 J9 PLANT MOL BIOL JI Plant Mol.Biol. PD NOV PY 1992 VL 20 IS 3 BP 377 EP 382 PG 6 WC Biochemistry & Molecular Biology; Plant Sciences SC Biochemistry & Molecular Biology; Plant Sciences GA JV556 UT WOS:A1992JV55600002 PM 1421141 ER PT J AU Anders, A Anders, S Forster, A Brown, IG AF Anders, Andre Anders, Simone Foerster, Andreas Brown, Ian G. TI Pressure ionization: its role in metal vapour vacuum arc plasmas and ion sources SO PLASMA SOURCES SCIENCE & TECHNOLOGY LA English DT Article AB In most plasmas ionization is brought about by classical ionizing collisions between panicles. In metal vapour vacuum arc plasmas and ion sources, however, pressure ionization plays an important role in determining the final ion composition. In this paper we describe the basic mechanism of pressure ionization as a collective phenomenon in non-ideal plasmas, induced mainly by the many-panicle Coulomb interaction and quantum-mechanical exchange. Then we outline the properties of the cathode spot plasmas of vacuum arc discharges. The path of the cathode material in the electron density-temperature phase diagram is considered; starting from the solid, the matter is heated, forms a liquid and then a supercritical fluid which expands explosively, driven by a very high pressure gradient. The final ion charge state distribution is produced and frozen in the transition from the dense. non-ideal plasma (where pressure ionization is dominant) to the expanded, ideal, non-equilibrium plasma. We conclude that the final ion charge state distribution depends on the thermophysical properties of the solid and liquid cathode material as well as on the electronic structure of its atoms and ions. Some consequences for the performance of the metal vapour vacuum arc ion source are discussed. C1 [Anders, Andre; Anders, Simone; Brown, Ian G.] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. [Foerster, Andreas] Humboldt Univ, Inst Theoret Phys, D-1040 Berlin, Germany. RP Anders, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Anders, Andre/B-8580-2009; Raoux, Simone/G-3920-2016 OI Anders, Andre/0000-0002-5313-6505; FU Deutsche Forschungsgemeinschaft [An 204/1-1, An 206/1-1]; US Department of Energy [DE-AC03-76SF00098] FX This work was supported by the Deutsche Forschungsgemeinschaft (An 204/1-1 and An 206/1-1), and by the US Department of Energy under Contract no DE-AC03-76SF00098. NR 76 TC 26 Z9 26 U1 1 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0963-0252 EI 1361-6595 J9 PLASMA SOURCES SCI T JI Plasma Sources Sci. Technol. PD NOV PY 1992 VL 1 IS 4 BP 263 EP 270 DI 10.1088/0963-0252/1/4/006 PG 8 WC Physics, Fluids & Plasmas SC Physics GA V10PW UT WOS:000207476900006 ER PT J AU ALLISON, DP BOTTOMLEY, LA THUNDAT, T BROWN, GM WOYCHIK, RP SCHRICK, JJ JACOBSON, KB WARMACK, RJ AF ALLISON, DP BOTTOMLEY, LA THUNDAT, T BROWN, GM WOYCHIK, RP SCHRICK, JJ JACOBSON, KB WARMACK, RJ TI IMMOBILIZATION OF DNA FOR SCANNING PROBE MICROSCOPY SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID TUNNELING MICROSCOPY; TUNNELLING MICROSCOPY; NUCLEIC-ACIDS; SPECTROSCOPY; MOLECULES; SURFACE; IMAGES; WATER AB Reproducible scanning tunneling microscope and atomic force microscope images of entire molecules of uncoated plasmid DNA chemically bound to surfaces are presented. The chemically mediated immobilization of DNA to surfaces and subsequent scanning tunneling microscope imaging of DNA molecules demonstrate that the problem of molecular instability to forces exerted by the probe tip, inherent with scanning probe microscopes, can be prevented. C1 OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. GEORGIA INST TECHNOL,DEPT CHEM & BIOCHEM,ATLANTA,GA 30332. UNIV TENNESSEE,GRAD SCH BIOMED SCI,KNOXVILLE,TN 37996. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. RP ALLISON, DP (reprint author), OAK RIDGE NATL LAB,DIV HLTH & SAFETY RES,OAK RIDGE,TN 37831, USA. OI Bottomley, Lawrence/0000-0002-2325-9862 NR 33 TC 58 Z9 58 U1 0 U2 6 PU NATL ACAD PRESS 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 NOV 1 PY 1992 VL 89 IS 21 BP 10129 EP 10133 DI 10.1073/pnas.89.21.10129 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JW798 UT WOS:A1992JW79800032 PM 1438201 ER PT J AU TURNQUIST, S SIMON, M EGELMAN, E ANDERSON, D AF TURNQUIST, S SIMON, M EGELMAN, E ANDERSON, D TI SUPERCOILED DNA WRAPS AROUND THE BACTERIOPHAGE-PHI-29 HEAD TAIL CONNECTOR SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE VIRAL DNA ENCAPSIDATION; SUPERCOILED DNA WRAPPED AROUND PROTEIN; DNA TRANSLOCATION MACHINE ID BACILLUS-SUBTILIS PHAGE-PHI-29; REPLICATION ORIGIN; PROTEIN; RESOLUTION; LAMBDA; RNA AB Supercoiled pBR322 DNA wraps around the outside of the isolated Bacillus subtilis bacteriophage phi29 head-tail connector, the crux of the DNA packaging machine of the viral precursor capsid or prohead. The contour length of the supercoiled DNA, determined by EM, decreased by almost-equal-to 180 base pairs for each connector bound. Mass and radial density determinations by scanning transmission EM showed that the increased mass of the connector-DNA complex relative to the connector alone was equivalent to almost-equal-to 170 base pairs of DNA and was located around the outside of the connector. Topoisomerase I treatment of the complexes followed by deproteinization suggested that supercoils were restrained by the connectors. Connectors bound linear and open-circular plasmid DNAs inefficiently but were not wrapped by these DNAs. The wrapping of supercoiled DNA around the isolated phi29 connector is hypothesized to reflect the initiation phase of the normal process of DNA packaging. Packaging substrates would be supercoiled, wrapped by the connector, linearized, and translocated by rotation of the connector relative to the viral capsid with the aid of ATP hydrolysis. C1 UNIV MINNESOTA,DEPT MICROBIOL,MINNEAPOLIS,MN 55455. BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973. UNIV MINNESOTA,DEPT ORAL SCI,MINNEAPOLIS,MN 55455. UNIV MINNESOTA,DEPT CELL BIOL & NEUROANAT,MINNEAPOLIS,MN 55455. RI Egelman, Edward/A-2488-2009 NR 20 TC 49 Z9 49 U1 0 U2 1 PU NATL ACAD PRESS 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 NOV 1 PY 1992 VL 89 IS 21 BP 10479 EP 10483 DI 10.1073/pnas.89.21.10479 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JW798 UT WOS:A1992JW79800103 PM 1438237 ER PT J AU RODRIGUEZ, A ALPEN, EL POWERSRISIUS, P AF RODRIGUEZ, A ALPEN, EL POWERSRISIUS, P TI THE RBE LET RELATIONSHIP FOR RODENT INTESTINAL CRYPT CELL-SURVIVAL, TESTES WEIGHT-LOSS, AND MULTICELLULAR SPHEROID CELL-SURVIVAL AFTER HEAVY-ION IRRADIATION SO RADIATION RESEARCH LA English DT Article ID CHARGED-PARTICLES; TELESCOPE DETECTOR; MAMMALIAN-CELLS; BEAMS; INACTIVATION; INSTRUMENTATION; RADIOBIOLOGY; HELIUM C1 LAWRENCE BERKELEY LAB,DIV CELL & MOLEC BIOL,BERKELEY,CA 94720. FU NCI NIH HHS [CA15184] NR 30 TC 17 Z9 17 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD NOV PY 1992 VL 132 IS 2 BP 184 EP 192 DI 10.2307/3578525 PG 9 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA JY583 UT WOS:A1992JY58300010 PM 1438700 ER PT J AU CAMERON, SM TRACY, MD ESTABROOK, KG DEGROOT, JS AF CAMERON, SM TRACY, MD ESTABROOK, KG DEGROOT, JS TI 2-DIMENSIONAL ELECTRON-DENSITY, TEMPERATURE, AND RADIAL DRIFT PROFILES OF A LASER PLASMA BY 266-NM COLLECTIVE THOMSON SCATTERING SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID STIMULATED BRILLOUIN-SCATTERING; TIME; TRANSPORT AB Collective Thomson scattering measurements performed al 266 nm on an underdense, long scalelength laser-produced aluminum plasma (n(c) approximately 10(21) cm-3, Z approximately 7, T(e) greater-than-or-equal-to 50 eV, L greater-than-or-equal-to 100 mum) under moderate irradiance conditions (10(11) W/cm2) are used to obtain temporally integrated, spatially resolved (30 mum) electron temperature, density, and radial fluid velocity contours. For an ultraviolet diagnostic wavelength, the effects of inverse bremsstrahlung heating perturbations and refractive turning are significantly reduced, allowing high density coronal conditions in the vicinity of one-tenth critical to be investigated. Detailed knowledge of these plasma conditions are fundamental prerequisites for understanding the distributed absorption process within fusion plasmas and for validation of the modeling accuracy of hydrodynamic codes. Fluid equations with classical coefficients should accurately apply to the plasma in these experiments because electron thermal transport is in the Spitzer regime, and the authors report relatively good agreement between the experimental results and two-dimensional LASNEX simulations. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. UNIV CALIF DAVIS,PLASMA RES GRP,DAVIS,CA 95616. RP CAMERON, SM (reprint author), UNIV CALIF DAVIS,DEPT APPL SCI,DAVIS,CA 95616, USA. NR 29 TC 8 Z9 8 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD NOV PY 1992 VL 63 IS 11 BP 5259 EP 5265 DI 10.1063/1.1143437 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA JW822 UT WOS:A1992JW82200006 ER PT J AU NISHITANI, T TAKEUCHI, H KONDOH, T ITOH, T KURIYAMA, M IKEDA, Y IGUCHI, T BARNES, CW AF NISHITANI, T TAKEUCHI, H KONDOH, T ITOH, T KURIYAMA, M IKEDA, Y IGUCHI, T BARNES, CW TI ABSOLUTE CALIBRATION OF THE JT-60U NEUTRON MONITORS USING A CF-252 NEUTRON SOURCE SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID ACTIVATION SYSTEM; TOKAMAK; TFTR; DETECTORS AB Absolutely calibrated measurements of the neutron yield are important for the evaluation of plasma performance such as the fusion gain Q in D-D operating tokamaks. The time-resolved neutron yield is measured with U-235 and U-238 fission chambers and He-3 proportional counters in the JT-60U tokamak. The in situ calibration was performed by moving the Cf-252 neutron source toroidally through the JT-60 vacuum vessel. Detection efficiencies of three U-235 and two He-3 detectors were measured for 92 locations of the neutron point source in toroidal scans at two different major radii. The total detection efficiency for the torus neutron source was obtained by averaging the point efficiencies over the whole toroidal angle. The uncertainty of the resulting detection efficiency for the plasma neutrons is estimated to be +/- 11%. C1 UNIV TOKYO,FAC ENGN,DEPT NUCL ENGN,BUNKYO KU,TOKYO 113,JAPAN. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP NISHITANI, T (reprint author), JAPAN ATOM ENERGY RES INST,NAKA FUS RES ESTAB,NAKA MACHI,IBARAKI 31101,JAPAN. NR 18 TC 58 Z9 58 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD NOV PY 1992 VL 63 IS 11 BP 5270 EP 5278 DI 10.1063/1.1143439 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA JW822 UT WOS:A1992JW82200008 ER PT J AU CUTHBERTSON, JW MOTLEY, RW LANGER, WD AF CUTHBERTSON, JW MOTLEY, RW LANGER, WD TI HIGH-FLUX SOURCE OF LOW-ENERGY NEUTRAL BEAMS USING REFLECTION OF IONS FROM METALS SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID SPACECRAFT AB Reflection of low-energy (< 100 ev) ions from surfaces can be applied as a method of producing high-flux beams of low-energy neutral particles, and is an important effect in several areas of plasma technology, such as in the edge region of fusion devices. We have developed a beam source based on acceleration and reflection of ions from a magnetically confined coaxial rf plasma Source. The beam provides a large enough flux (over 4 A ion current, or 5 X 10(16) atoms/cm2 s at 10-cm range) to allow the energy distribution of the reflected neutrals to be measured despite the inefficiency of detection, by means of an electrostatic cylindrical mirror analyzer coupled with a quadrupole mass spectrometer. Energy distributions have been measured for oxygen, nitrogen and inert gas ions incident with from 15 to 70 eV reflected from amorphous metal surfaces of several compositions. For ions of lighter atomic mass than the reflecting metal, reflected beams have peaked energy distributions; beams with the peak at 4-32 eV have been measured. The energy and mass dependences of the energy distributions as well as measurements of absolute flux, and angular distribution and divergence are reported. Applications of the neutral beams produced are described. RP CUTHBERTSON, JW (reprint author), PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 18 TC 12 Z9 12 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD NOV PY 1992 VL 63 IS 11 BP 5279 EP 5288 DI 10.1063/1.1143440 PG 10 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA JW822 UT WOS:A1992JW82200009 ER PT J AU NAZIKIAN, R AF NAZIKIAN, R TI MODULATIONAL SOURCES, SIDE-BAND CORRELATIONS AND NONSTATIONARY INTERFERENCE FOR WAVES SCATTERED FROM RANDOM-MEDIA SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID FLUCTUATIONS AB For the small angle scattering of coherent plane waves from inhomogeneous random media, the three-dimensional mean square distribution of random fluctuations may be recovered from the interferometric detection of the nonstationary modulational structure of the scattered field. Modulational properties of coherent waves scattered from random media are related to nonlocal correlations in the double sideband structure of the scattered field. To second order, such correlations may be expressed in terms of a suitably generalized spectral coherence function for analytic fields. RP NAZIKIAN, R (reprint author), PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 15 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 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD NOV PY 1992 VL 63 IS 11 BP 5326 EP 5331 DI 10.1063/1.1143448 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA JW822 UT WOS:A1992JW82200017 ER PT J AU CIZEWSKI, JA BECKER, JA HENRY, EA BRINKMAN, MJ STEPHENS, FS DELEPLANQUE, MA DIAMOND, RM AZAIEZ, F MACCHIAVELLI, AO AF CIZEWSKI, JA BECKER, JA HENRY, EA BRINKMAN, MJ STEPHENS, FS DELEPLANQUE, MA DIAMOND, RM AZAIEZ, F MACCHIAVELLI, AO TI SYMMETRIES IN SUPERDEFORMED NUCLEI SO REVISTA MEXICANA DE FISICA LA English DT Article; Proceedings Paper CT 15TH SYMP ON NUCLEAR PHYSICS CY JAN 07-10, 1992 CL OAXTEPEC, MEXICO SP COORDINAC INVESTIGAC CIENT, INT CTR THEORET PHYS, INST CIENCIAS NUCL, INST FIS, INST NACL INVESTIGAC NUCL, SECRETARIA EDUC PUBLICA, SOC MEXICANA FIS ID BANDS; ALIGNMENT; HG-191; TL-194 AB A large number of superdeformed rotational bands in the A=194 region have gamma-ray transition energies identical or related to those of the strongly populated SD band in 192Hg. These identical structures are interpreted in terms of the multi-fermion supersymmetries which occur in the IBFA framework. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. UNIV CALIF BERKELEY,BERKELEY,CA 94720. RP CIZEWSKI, JA (reprint author), RUTGERS STATE UNIV,DEPT PHYS & ASTRON,NEW BRUNSWICK,NJ 08903, USA. NR 28 TC 3 Z9 3 U1 0 U2 0 PU SOCIEDAD MEXICANA DE FISICA PI COYOACAN PA APARTADO POSTAL 70-348, COYOACAN 04511, MEXICO SN 0035-001X J9 REV MEX FIS JI Rev. Mex. Fis. PD NOV PY 1992 VL 38 SU 2 BP 16 EP 25 PG 10 WC Physics, Multidisciplinary SC Physics GA KA605 UT WOS:A1992KA60500004 ER PT J AU ZHU, S ZHAO, X HAMILTON, JH RAMAYYA, AV LU, Q MA, WC PEKER, LK KORMICKI, J XIE, H GAO, WB DENG, JK LEE, IY JOHNSON, NR MCGOWAN, FK BEMIS, CE COLE, JD ARYAEINEJAD, R TERAKOPIAN, G OGANESSIAN, Y AF ZHU, S ZHAO, X HAMILTON, JH RAMAYYA, AV LU, Q MA, WC PEKER, LK KORMICKI, J XIE, H GAO, WB DENG, JK LEE, IY JOHNSON, NR MCGOWAN, FK BEMIS, CE COLE, JD ARYAEINEJAD, R TERAKOPIAN, G OGANESSIAN, Y TI HIGHER SPIN STATES IN NEUTRON RICH NUCLEI SO REVISTA MEXICANA DE FISICA LA English DT Article; Proceedings Paper CT 15TH SYMP ON NUCLEAR PHYSICS CY JAN 07-10, 1992 CL OAXTEPEC, MEXICO SP COORDINAC INVESTIGAC CIENT, INT CTR THEORET PHYS, INST CIENCIAS NUCL, INST FIS, INST NACL INVESTIGAC NUCL, SECRETARIA EDUC PUBLICA, SOC MEXICANA FIS ID GROUND-STATES; 100 REGION; DEFORMATION; ISOTOPES; OCTUPOLE; DECAY; KR AB Recent studies of the products produced in spontaneous fission (SF) have shown an unexpected richness of information about previously inaccessible higher spin studies in neutron rich nuclei. Recent evidence for octupole deformation in Ba-144, Ba-146, 164Yb and Ra-226 have come from SF and other techniques. New insights into the structure of nuclei in the A = 100-120 and 136-152 regions have been obtained from two different SF gamma - gamma coincidence studies of Cf-252 in a Close Packed Ball with 20 Compton suppressed Ge detectors, where one experiment also included a fission fragment detector inside the ball at the Holifield Heavy Ion Research Facility, as well as a similar study at Argonne. New data resolve problems related to shape coexistence in 100Sr, Zr-102 and provide new insights into the super deformation in this region. New high spin states up to 16+, a record in such neutron rich nuclei, were found in Xe-138, Xe-140, Ba-140 Ce-146-150 and Nd-150, Nd-152 in our HHIRF work and levels identified for the first time in 136Te and 149Ce. The J1 moments of inertia for Ge-148, Ge-150 and Nd-150, Nd-152 exhibit an unexpected crossing pattern at high spins. These data also provide new insight into the fission process itself. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415. DUBNA JOINT NUCL RES INST,DUBNA,USSR. RP ZHU, S (reprint author), VANDERBILT UNIV,DEPT PHYS,NASHVILLE,TN 37235, USA. NR 28 TC 21 Z9 22 U1 0 U2 1 PU SOCIEDAD MEXICANA DE FISICA PI COYOACAN PA APARTADO POSTAL 70-348, COYOACAN 04511, MEXICO SN 0035-001X J9 REV MEX FIS JI Rev. Mex. Fis. PD NOV PY 1992 VL 38 SU 2 BP 53 EP 65 PG 13 WC Physics, Multidisciplinary SC Physics GA KA605 UT WOS:A1992KA60500008 ER PT J AU STANSFIELD, SA AF STANSFIELD, SA TI HAPTIC PERCEPTION WITH AN ARTICULATED, SENSATE ROBOT HAND SO ROBOTICA LA English DT Article DE ROBOT HAND; HAPTIC PROCEDURE; INTELLIGENT ROBOT; TOUCH SYSTEM AB In this paper we present a series of haptic exploratory procedures, or EPs, implemented for a multi-fingered, articulated, sensate robot hand. These EPs are designed to extract specific tactile and kinesthetic information from an object via their purposive invocation by an intelligent robotic system. Taken together, they form an active robotic touch perception system to be used both in extracting information about the environment for internal representation and in acquiring grasps for manipulation. The theory and structure of this robotic haptic system is based upon models of human haptic exploration and information processing. The haptic system presented utilizes an integrated robotic system consisting of a PUMA 560 robot arm, a JPL/Stanford robot hand, with joint torque sensing in the fingers, a wrist force/torque sensor, and a 256 element, spatially-resolved fingertip tactile array. We describe the EPs implemented for this system and provide experimental results which illustrate how they function and how the information which they extract may be used. In addition to the sensate hand and arm, the robot also contains structured-lighting vision and a Prolog-based reasoning system capable of grasp generation and object categorization. We present a set of simple tasks which show how both grasping and recognition may be enhanced by the addition of active touch perception. RP STANSFIELD, SA (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 0 TC 5 Z9 5 U1 1 U2 2 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 SN 0263-5747 J9 ROBOTICA JI Robotica PD NOV-DEC PY 1992 VL 10 BP 497 EP 508 PN 6 PG 12 WC Robotics SC Robotics GA JZ350 UT WOS:A1992JZ35000012 ER PT J AU DENDY, JE IDA, MP RUTLEDGE, JM AF DENDY, JE IDA, MP RUTLEDGE, JM TI A SEMICOARSENING MULTIGRID ALGORITHM FOR SIMD-MACHINES SO SIAM JOURNAL ON SCIENTIFIC AND STATISTICAL COMPUTING LA English DT Article DE MULTIGRID; PARALLEL COMPUTING ID GRID METHOD; COEFFICIENTS AB A semicoarsening multigrid algorithm suitable for use on single instruction multiple data (SIMD) architectures has been implemented on the CM-2. The method performs well for strongly anisotropic problems and for problems with coefficients jumping by orders of magnitude across internal interfaces. The parallel efficiency of this method is analyzed, and its actual performance is compared with its performance on some other machines, both parallel and nonparallel. C1 CALTECH, PASADENA, CA 91125 USA. STAND OIL CALIF, CHEVRON OIL FIELD RES CO, LA HABRA, CA 90631 USA. RP LOS ALAMOS NATL LAB, DIV THEORET PHYS, LOS ALAMOS, NM 87545 USA. NR 19 TC 30 Z9 31 U1 0 U2 1 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0196-5204 J9 SIAM J SCI STAT COMP PD NOV PY 1992 VL 13 IS 6 BP 1460 EP 1469 PG 10 WC Mathematics, Applied SC Mathematics GA JU936 UT WOS:A1992JU93600011 ER PT J AU KLUBEK, B CARLSON, CL OLIVER, J ADRIANO, DC AF KLUBEK, B CARLSON, CL OLIVER, J ADRIANO, DC TI CHARACTERIZATION OF MICROBIAL ABUNDANCE AND ACTIVITY FROM 3 COAL ASH BASINS SO SOIL BIOLOGY & BIOCHEMISTRY LA English DT Article ID FLY-ASH; BIOLOGICAL PROPERTIES; SOIL; ECOSYSTEMS AB The effects of coal ash (differing in age by the time of disposal) on the abundance of soil microorganisms, dehydrogenase activity and soil respiration were assessed. Samples of sluiced and cyclone-bottom ash from two abandoned sites, and one sluiced-ash site, currently in use, were collected at the Savannah River Site in Barnwell County, S.C. Soil samples collected near the ash basins were used as a control. There were significant differences by location in the estimates of actinomycetes, culturable bacteria, fungi, amylolytic organisms, and nitrifying, denitrifying and selenate-reducing bacteria. In general, higher estimates of actinomycetes, bacteria, fungi, amylolytic organisms and denitrifying bacteria were obtained from the abandoned sluiced-ash basin. The estimates of nitrifying and selenate-reducing bacteria were highest in the new ash basin currently in use. Microbial populations were correlated with pH, % total C, or % total N. Most of the correlations were associated with total N. Microbial diversity indices (phyleal and physiological) were determined to be low (< 1.0) for all locations. However, phyleal diversity indices also correlated with % total N. Increases in dehydrogenase activity and soil respiration were observed when ash or soil samples were treated with glucose or glucose plus ammonium nitrate, indicating that the availability of simple organic compounds and N are limiting factors for microbial activity. Cumulative CO2 evolution indicated that a priming effect occurred by day 15 of incubation after glucose or glucose plus ammonium nitrate had been applied. The results suggest that the abundance, diversity and activity of microorganisms increase as the ash basin ages. The land-disposal of fly ash will require the addition of low C:N ratio residues to stimulate microbial community development. C1 CLEMSON UNIV,EDISTO RES & EDUC CTR,BLACKVILLE,SC 29801. SAVANNAH RIVER ECOL LAB,AIKEN,SC 29801. RP KLUBEK, B (reprint author), SO ILLINOIS UNIV,DEPT PLANT & SOIL SCI,CARBONDALE,IL 62901, USA. NR 27 TC 22 Z9 22 U1 2 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-0717 J9 SOIL BIOL BIOCHEM JI Soil Biol. Biochem. PD NOV PY 1992 VL 24 IS 11 BP 1119 EP 1125 DI 10.1016/0038-0717(92)90062-3 PG 7 WC Soil Science SC Agriculture GA JX581 UT WOS:A1992JX58100008 ER PT J AU SHOUSE, PJ SISSON, JB ELLSWORTH, TR JOBES, JA AF SHOUSE, PJ SISSON, JB ELLSWORTH, TR JOBES, JA TI ESTIMATING INSITU UNSATURATED HYDRAULIC-PROPERTIES OF VERTICALLY HETEROGENEOUS SOILS SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article; Proceedings Paper CT 57TH ANNUAL MEETING OF THE SOIL SCIENCE SOC OF AMERICA CY NOV 07-12, 1993 CL CINCINNATI, OH SP SOIL SCI SOC AMER ID WATER PROPERTIES; SOLUTE TRANSPORT; FIELD; DRAINAGE; CONDUCTIVITIES; METHODOLOGY; MODELS; MEDIA; FLOW AB The majority of procedures for in situ measurement of the unsaturated hydraulic conductivity are variations of the instantaneous profile method. A vertically nonuniform soil requires the unsaturated hydraulic functions to be estimated at each horizon. Scaling systems have evolved in an attempt to reduce the number of hydraulic functions needed to characterize water flow through heterogeneous soils. In this study, we extended the concept of water content (theta) scaling to nonuniform soil profiles, tested the effectiveness of theta scaling for reducing apparent spatial variability, and estimated the unsaturated hydraulic functions for a naturally occurring loam sand field site. Two instantaneous profile experiments conducted at Etiwanda, CA, provided soil water content and pressure head (h) data vs. depth (z) and time (t). Water retention, theta(h), and hydraulic conductivity, K(theta), functions fitted to data from the 15-cm depth at Plot 1 were arbitrarily chosen as the reference hydraulic properties to which the other depths and plots were scaled. Based on a unit-gradient analysis of the drainage data, the slope of the hydraulic conductivity function, dK/dtheta, was estimated as z/t. Scaling other depths and plots to the reference location was done using an iterative procedure that provided least-squares estimates of the two theta scaling parameters (delta and mu) and a corresponding transformed depth variable (z*). Scaled water content, theta*, plotted vs. z*/t, using data from all depths and plots, coalesced to a single curve. Scaling theta successfully coalesced heterogeneous soil hydraulic properties into unique functions for both theta(h) and K(theta). C1 EG&G IDAHO INC,DIV GEOSCI,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415. UNIV ILLINOIS,DEPT AGRON,URBANA,IL 61801. RP SHOUSE, PJ (reprint author), USDA ARS,US SALIN LAB,4500 GLENWOOD DR,RIVERSIDE,CA 92501, USA. NR 25 TC 13 Z9 13 U1 1 U2 2 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD NOV-DEC PY 1992 VL 56 IS 6 BP 1673 EP 1679 PG 7 WC Soil Science SC Agriculture GA KJ488 UT WOS:A1992KJ48800003 ER PT J AU ODELL, JD WOLT, JD JARDINE, PM AF ODELL, JD WOLT, JD JARDINE, PM TI TRANSPORT OF IMAZETHAPYR IN UNDISTURBED SOIL COLUMNS SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article; Proceedings Paper CT 57TH ANNUAL MEETING OF THE SOIL SCIENCE SOC OF AMERICA CY NOV 07-12, 1993 CL CINCINNATI, OH SP SOIL SCI SOC AMER ID POLYNUCLEAR ALUMINUM; IMAZAQUIN; ADSORPTION; MOBILITY; MONONUCLEAR; SPECIATION; MOVEMENT; FERRON; CORES; PH AB The disappearance of imazethapyr [(+/-)-2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazole-2-yl]-5-ethyl-3-pyridinecarboxylic acid] from soil solution was investigated to evaluate the transport of imazethapyr in undisturbed soil columns. Soil treated with imazethapyr was incubated for 0.15, 1, 2, 4, 8, and 16 d, at which times soil solution was obtained by vacuum displacement. Bromide and imazethapyr wert then applied to the surface of undisturbed soil columns followed by application of deionized water at approximately 3 cm d-1. The removal of imazethapyr from solution (i.e., sorption) exhibited biphasic kinetics and was well described (R2 = 0.99) by two simultaneous first-order reactions. The initial reaction was essentially instantaneous and the secondary reaction was time dependent. The classical convective-dispersive ( CD) equation was used to describe solute transport through undisturbed soil columns. Bromide and imazethapyr breakthrough curves (BTCs) were displaced to the left of one pore volume and showed considerable tailing, with imazethapyr BTCs retarded in relation to Br-. This was indicative of preferential solute mobility in the soil. Imazethapyr BTCs were similar to model simulations using transport parameters determined from Br BTCs, kinetic parameters from the imazethapyr solution concentration decay curves, and retardation factors calculated from the distribution coefficient at the 1-d incubation time. Model simulations using retardation factors from later times predicted increasingly delayed imazethapyr breakthrough with lower peak concentrations than measured. Preferential flow paths apparently reduced attenuation of imazethapyr as predicted from equilibrium adsorption measurements. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. DOWELANCO,INDIANAPOLIS,IN 46268. RP ODELL, JD (reprint author), UNIV TENNESSEE,DEPT PLANT & SOIL SCI,KNOXVILLE,TN 37901, USA. NR 23 TC 24 Z9 24 U1 0 U2 1 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD NOV-DEC PY 1992 VL 56 IS 6 BP 1711 EP 1715 PG 5 WC Soil Science SC Agriculture GA KJ488 UT WOS:A1992KJ48800008 ER PT J AU WILSON, GV JARDINE, PM GWO, JP AF WILSON, GV JARDINE, PM GWO, JP TI MODELING THE HYDRAULIC-PROPERTIES OF A MULTIREGION SOIL SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article; Proceedings Paper CT 57TH ANNUAL MEETING OF THE SOIL SCIENCE SOC OF AMERICA CY NOV 07-12, 1993 CL CINCINNATI, OH SP SOIL SCI SOC AMER ID 2 FORESTED WATERSHEDS; SOLUTE TRANSPORT; STORM EVENTS; MACROPOROSITY; CONDUCTIVITY; HILLSLOPE; MESOPOROSITY AB Numerical techniques for modeling transport of solutes in multiple porosity systems have recently been developed to better represent the physical attributes of structured soils. Multiregion flow modeling requires characterization of the water content (theta) and hydraulic conductivity (K) as a function of pressure head (h) for each region of the system. A technique is presented for determining the theta(h) and K(h) relationships for a three-region soil system based on a typical water retention data base. The demarcation between Region 1 (macropore) and Region 2 (mesopore) was assumed to occur at h = -10 cm. The effect of this assumption was evaluated against criteria of h = -2 and -25 cm, with h = -10 cm giving the best results. The theta(h) function was described as a Fermi function for Region 1 and combined with the van Genuchten model for describing Regions 2 and 3 (micropore). Continuity in theta(h) and K(theta) between regions was achieved and an excellent agreement between predicted and measured values was obtained for each region. However, the derivative of the theta(h) and K(theta) functions were occasionally not continuous through the junction points. The Fermi function based on measured and assumed parameters gave erroneous predictions of K(theta) when a large (25-cm) range in h was used for Region 1. A modified Fermi function was developed that gave an excellent prediction of K(theta) based on assumed parameters. C1 OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. PENN STATE UNIV,UNIV PK,PA 16802. RP WILSON, GV (reprint author), UNIV TENNESSEE,KNOXVILLE,TN 37901, USA. NR 21 TC 65 Z9 66 U1 0 U2 5 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD NOV-DEC PY 1992 VL 56 IS 6 BP 1731 EP 1737 PG 7 WC Soil Science SC Agriculture GA KJ488 UT WOS:A1992KJ48800012 ER PT J AU PETTERSEN, BR HAWLEY, SL FISHER, GH AF PETTERSEN, BR HAWLEY, SL FISHER, GH TI STARSPOTS - THE ZEBRA EFFECT SO SOLAR PHYSICS LA English DT Article ID ROTATIONAL MODULATION; SOLAR LUMINOSITY; RS-CVN; MAGNETIC ACTIVITY; IUE OBSERVATIONS; DRACONIS STARS; FLARE STARS; II-PEGASI; AR-LAC; DRA AB Recent observations of brightness variations on the Sun during the solar cycle have motivated us to re-examine the widely held view that cool, dark starspots, covering a significant fraction of the star, are the centers of magnetic activity on BY Dra stars. We propose that the magnetic regions are better described by a bright facular network, and that the dark areas which give rise to photometric rotational modulation are actually regions where the underlying quiet photosphere is seen. This interpretation is consistent with recent observations of late-type stars that show that bright areas covering much of the star have magnetic fields with strengths of several thousand gauss. It resolves several problems with the current model, including the size, location, and stability of the starspots required to match photometric and Doppler-imaging observations. It also has interesting observational implications for the correlation of photometric rotational modulation and long term brightness variations with other surface activity, and for the positions of magnetically active stars in the H-R diagram. C1 LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550. UNIV HAWAII,INST ASTRON,HONOLULU,HI 96822. RP PETTERSEN, BR (reprint author), UNIV OSLO,INST THEORET ASTROPHYS,OSLO 3,NORWAY. RI Fisher, George/G-1380-2015 OI Fisher, George/0000-0002-6912-5704 NR 34 TC 8 Z9 8 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD NOV PY 1992 VL 142 IS 1 BP 197 EP 204 DI 10.1007/BF00156642 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JX667 UT WOS:A1992JX66700014 ER PT J AU PLAKHTY, V STRATILATOV, A CHERNENKOV, Y FEDOROV, V SINHA, SK LOONG, CK GAULIN, B VLASOV, M MOSHKIN, S AF PLAKHTY, V STRATILATOV, A CHERNENKOV, Y FEDOROV, V SINHA, SK LOONG, CK GAULIN, B VLASOV, M MOSHKIN, S TI X-RAY STUDIES OF THE YBA2CU3O6+X SUPERSTRUCTURES IN THE RANGE OF 0.40(3)LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-0.73(3) SO SOLID STATE COMMUNICATIONS LA English DT Article ID ELECTRON-DIFFRACTION; PHASE-DIAGRAM; OXYGEN; YBA2CU3O7-DELTA; SUPERCONDUCTORS; TRANSITION; MICROSCOPY; ORDER AB By means of X-Ray diffraction on single crystals of YBa2Cu3O6+x with a well defined oxygen content it is shown that the ortho-II phase 2a0xb0 exists in the range of 0.40(3) less-than-or-equal-to x less-than-or-equal-to 0.63. The crystals with x = 0.70(3) and x = 0.73(3) possess the 3a0xb0 superstructure. Both are caused by a short-range ordering of the Cu(1)-oxygen and Cu(1)-vacancy chains. The antiparallel displacements a0x(y) = 0.011(1)angstrom, a0x(Ba) = -0.039(1)angstrom, c0z(Cu(2)) = 0.018(2)angstrom, and c0z0(1) = 0.049(7)angstrom are determined for the x = 0.58(2) by a profile refinement method. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. EXXON RES & ENGN CO,CORP RES,ANNANDALE,NJ 08801. MCMASTER UNIV,HAMILTON L8S 4L8,ONTARIO,CANADA. ST PETERSBURG UNIV,ST PETERSBURG 199034,USSR. RP PLAKHTY, V (reprint author), PETERSBURG NUCL PHYS INST,ST PETERSBURG 188350,USSR. RI Piper, Walter/B-7908-2009 NR 28 TC 41 Z9 41 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD NOV PY 1992 VL 84 IS 6 BP 639 EP 644 DI 10.1016/0038-1098(92)90207-P PG 6 WC Physics, Condensed Matter SC Physics GA JZ060 UT WOS:A1992JZ06000013 ER PT J AU BUDHANI, RC SUENAGA, M AF BUDHANI, RC SUENAGA, M TI HEAVY-ION IRRADIATION AND THE VORTEX-GLASS DESCRIPTION OF THE MIXED STATE IN YBA2CU3O7 EPITAXIAL-FILMS SO SOLID STATE COMMUNICATIONS LA English DT Article ID BA-CU-O; SUPERCONDUCTIVITY; CRYSTALS; PHASE; FIELD AB We report the behavior of the Ohmic resistivity and the current-dependent dissipation in the mixed state of YBa2Cu3O7 films irradiated with 300 MeV gold ions. The transport in both irradiated and unirradiated states of the samples agrees with the model of a second order phase transition to a vortex glass state. While the zero-field critical temperature and current are reduced by the irradiation, the vortex-glass description of the mixed state remains unchanged up to a dosage of approximately 9 x 10(10) ions/cm2. These results indicate that in these high J(c) films the vortex dynamics is controlled by pinning centers distributed at a length scale much shorter than the gold-ion induced defects. RP BUDHANI, RC (reprint author), BROOKHAVEN NATL LAB,DIV MAT SCI,UPTON,NY 11973, USA. NR 19 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD NOV PY 1992 VL 84 IS 8 BP 831 EP 834 DI 10.1016/0038-1098(92)90100-N PG 4 WC Physics, Condensed Matter SC Physics GA JZ711 UT WOS:A1992JZ71100013 ER PT J AU Rocha, J Klinowski, J Barrie, PJ Jelinek, R Pines, A AF Rocha, Joao Klinowski, Jacek Barrie, Patrick J. Jelinek, Raz Pines, Alexander TI Solid-state Al-27 NMR studies of aluminophosphate molecular sieves SO SOLID STATE NUCLEAR MAGNETIC RESONANCE LA English DT Article DE Al-27 NMR; aluminophosphate; molecular sieves; quadrupole mutation; double-rotation AB Solid-state Al-27 NMR spectra of several aluminophosphate molecular sieves have been recorded with conventional magic-angle spinning (MAS), double-rotation (DOR) and quadrupole nutation with fast MAS. Enhanced resolution was obtained in the quadrupole nutation experiment at certain radiofrequency pulse strengths. This extra resolution can be comparable to that attainable using DOR, and does not introduce spinning sidebands. C1 [Rocha, Joao; Klinowski, Jacek] Univ Cambridge, Dept Chem, Cambridge CB2 1EW, England. [Barrie, Patrick J.] Univ Coll London, Dept Chem, London WC1H 0AJ, England. [Jelinek, Raz; Pines, Alexander] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. [Jelinek, Raz; Pines, Alexander] Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Klinowski, J (reprint author), Univ Cambridge, Dept Chem, Lensfield Rd, Cambridge CB2 1EW, England. RI Rocha, Joao/A-2486-2010 OI Rocha, Joao/0000-0002-0417-9402 FU Office of Basic Energy Sciences, Materials and Chemical Sciences Division, U.S. Department of Energy [DE-AC03-76SF00098] FX We are grateful to Heyong He for sample preparation. The DOR work (R.J. and A.P.) was supported by the Director, Office of Basic Energy Sciences, Materials and Chemical Sciences Division, U.S. Department of Energy, under contract no. DE-AC03-76SF00098. NR 33 TC 13 Z9 13 U1 0 U2 4 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0926-2040 J9 SOLID STATE NUCL MAG JI Solid State Nucl. Magn. Reson. PD NOV PY 1992 VL 1 IS 4 BP 217 EP 225 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Spectroscopy SC Chemistry; Physics; Spectroscopy GA V26HS UT WOS:000208537300007 PM 1365734 ER PT J AU AYACHE, J BOIRE, P FERT, AR BOZEC, X CHEN, N ROUTBORT, JL AF AYACHE, J BOIRE, P FERT, AR BOZEC, X CHEN, N ROUTBORT, JL TI MICROSTRUCTURE AND MAGNETIC CHARACTERIZATION OF YBA2CU3O7-X SUPERCONDUCTING CERAMIC SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID DEPENDENCE; CURRENTS; OXYGEN AB Microstructure and microchemistry characterizations have been made using analytical transmission electron microscopy in order to correlate extended defect formation to intergranular and intragranular current density values. AC magnetization curves as a function of applied magnetic field at 4.2 and 77 K have been obtained. The results show that a large density of twins favours a high intragranular critical current density. In addition, the formation of cationic non-stoichiometric phases can act as vortex pinning centres. The relatively high intergranular current density is in good agreement with the observed absence of intergranular grain boundary phases. C1 INSA,PHYS SOLIDES LAB,F-31077 TOULOUSE,FRANCE. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP AYACHE, J (reprint author), CNRS,PHYS MAT LAB,F-92195 MEUDON,FRANCE. NR 15 TC 8 Z9 8 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD NOV PY 1992 VL 5 IS 11 BP 634 EP 639 DI 10.1088/0953-2048/5/11/006 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA KB190 UT WOS:A1992KB19000006 ER PT J AU LEVIEV, GI PIKOVSKY, AS COOKE, DW AF LEVIEV, GI PIKOVSKY, AS COOKE, DW TI RESPONSE OF GRANULAR SUPERCONDUCTORS TO LARGE-AMPLITUDE MICROWAVE FIELDS SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID HIGH-TC SUPERCONDUCTORS; THIN-FILMS; SURFACE-RESISTANCE; POWER; ABSORPTION; MODEL; RF AB We calculate the impedance of a granular superconductor for different levels of microwave field using a macroscopic nonlinear model. In this model Josephson junctions between grains are responsible for high-frequency current and field characteristics The change in surface impedance at the frequency of weak amplitude wave, when perturbed by a strong amplitude wave of different frequency, is also calculated. Application of the obtained nonlinear properties to experimental data is discussed. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. CHERNOBOLOVKA SOLID STATE PHYS INST,CHERNOGOLOVKA,USSR. RP LEVIEV, GI (reprint author), BERG UNIV WUPPERTAL,DEPT PHYS,GAUSSSTR 20,W-5600 WUPPERTAL 1,GERMANY. RI Pikovsky, Arkady/A-5225-2015 OI Pikovsky, Arkady/0000-0001-9682-7122 NR 26 TC 6 Z9 6 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD NOV PY 1992 VL 5 IS 11 BP 679 EP 683 DI 10.1088/0953-2048/5/11/015 PG 5 WC Physics, Applied; Physics, Condensed Matter SC Physics GA KB190 UT WOS:A1992KB19000015 ER PT J AU SHINN, ND AF SHINN, ND TI OBSERVATION OF A STABLE METHOXY INTERMEDIATE ON CR(110) SO SURFACE SCIENCE LA English DT Article ID PHOTON-STIMULATED DESORPTION; MODIFIED FE(100) SURFACES; ULTRAVIOLET PHOTOEMISSION; STRETCHING FREQUENCY; CO CHEMISORPTION; MOLECULAR ADSORPTION; ELECTRONIC-STRUCTURE; THERMAL-DESORPTION; PREADSORBED OXYGEN; ORGANIC-MOLECULES AB Ultraviolet photoelectron spectroscopy (UPS) and work function changes are used to identify a stable methoxy intermediate, CH3O(ads), on Cr(110) at 90 K following low exposures of methanol, CH3OH(g). Higher methanol exposures at 90 K add subsequent layers of physisorbed methanol which desorb above 120 K. Methoxy dissociation into atomic fragments occurs between 250 and 400 K. The absence of a stable CO(ads) dissociation intermediate indicates that methyl group dehydrogenation is rate limiting on Cr(110). As was previously found on Fe(100) and Mo(100), the stability of CH3O(ads) over CO(ads) on Cr(110) is opposite of that proposed by Sexton based upon relative heats of adsorption. Consideration of the CH3O: metal and CO: metal bonding mechanisms leads to the proposition that substrate electronic properties, rather than steric or substrate morphological factors, are responsible for the anomalous methoxy stability on these surfaces. RP SHINN, ND (reprint author), SANDIA NATL LABS,DEPT 1114,ALBUQUERQUE,NM 87185, USA. NR 46 TC 18 Z9 18 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD NOV 1 PY 1992 VL 278 IS 1-2 BP 157 EP 165 DI 10.1016/0039-6028(92)90591-S PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA JV841 UT WOS:A1992JV84100023 ER PT J AU SCHOEB, AM RAEKER, TJ YANG, LQ WU, X KING, TS DEPRISTO, AE AF SCHOEB, AM RAEKER, TJ YANG, LQ WU, X KING, TS DEPRISTO, AE TI DRIVING FORCE FOR SURFACE SEGREGATION IN BIMETALLIC CATALYSTS SO SURFACE SCIENCE LA English DT Letter ID CORRECTED EFFECTIVE-MEDIUM; MOLECULAR-DYNAMICS; SIMULATIONS; CU AB The catalytic properties of bimetallic clusters are influenced by the detailed structure of the cluster surface. We briefly describe two methods developed to treat this problem, from the computationally demanding corrected effective medium (CEM) theory (a non-self-consistent density functional based method) to the computationally simple method of surface modified pair potentials (SMPP). Parametrization of the latter is accomplished using the former. Comparisons of theoretical predictions with experimental data are made for the heat of formation in RhxPt1-x alloys and for surface segregation behavior in Rh0.9Pt0.1(111). Results on the shape, site composition and surface micromixing are shown for 201 atom clusters (dispersion of 0.6) and RhxPt1-x(111). A fundamental point follows from the fact that the CEM calculated cohesive energy of Rh is slightly smaller than that of Pt, but the surface energy of Rh is significantly larger: the driving force for surface segregation is the relative surface energies not the relative cohesive energies. In general, one can predict surface energy differences by properly accounting for the variation of the bond energy with coordination. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM ENGN,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP SCHOEB, AM (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 20 TC 30 Z9 30 U1 2 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD NOV 1 PY 1992 VL 278 IS 1-2 BP L125 EP L130 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA JV841 UT WOS:A1992JV84100005 ER PT J AU FOWLER, JS VOLKOW, ND MACGREGOR, RR LOGAN, J DEWEY, SL GATLEY, SJ WOLF, AP AF FOWLER, JS VOLKOW, ND MACGREGOR, RR LOGAN, J DEWEY, SL GATLEY, SJ WOLF, AP TI COMPARATIVE PET STUDIES OF THE KINETICS AND DISTRIBUTION OF COCAINE AND COCAETHYLENE IN BABOON BRAIN SO SYNAPSE LA English DT Article DE ALCOHOL; COCAINE; COCAETHYLENE; DEBENZOYLATION; BUTYRYLCHOLINESTERASE; PET ID DOPAMINE; PLASMA; METABOLITES; HYDROLYSIS; ALCOHOL; BINDING AB Recent studies have suggested that cocaethylene, an active metabolite of cocaine found in blood and postmortem brain of individuals self-administering cocaine and alcohol, may play a role in the increased toxicity seen when coadministering these 2 drugs. We have used positron emission tomography (PET) and carbon-11 (t1/2: 20.4 min) labeled cocaine and cocaethylene to compare the short-term kinetics of cocaine and cocaethylene in baboon brain. The regional uptake of [C-11]cocaine ([C-11]COC) and [C-11]cocaethylene ([C-11]CE), 5-8 mCi and 4-6 mug, in baboon brain (n = 7) were similar but clearance from whole brain (global, GL) and from striatum (SR), thalamus (TH), and cerebellum (CB) was slower for cocaethylene. Steady-state distribution volumes (DV) were not significantly different in the striatum but were greater for cocaethylene in the thalamus, cerebellum, and whole brain. Debenzoylation of cocaethylene proceeded at about one-third the rate of cocaine, as determined by in vitro incubation of labeled cocaethylene and labeled cocaine with baboon plasma and with purified horse butyryl-cholinesterase (EC 3.1.1.8). Even though the slower clearance of cocaethylene could lead to longer tissue exposures and potentially accentuated or different physiological effects relative to cocaine, the difference between the 2 drugs is not large. Thus it is more likely that the direct actions of cocaine and alcohol on some organs, rather than cocaethylene, account for this enhanced toxicity. C1 BROOKHAVEN NATL LAB, DEPT MED, UPTON, NY 11973 USA. RP BROOKHAVEN NATL LAB, DEPT CHEM, UPTON, NY 11973 USA. FU NIDA NIH HHS [DA 06278]; NINDS NIH HHS [NS 15638] NR 33 TC 31 Z9 31 U1 1 U2 4 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0887-4476 EI 1098-2396 J9 SYNAPSE JI Synapse PD NOV PY 1992 VL 12 IS 3 BP 220 EP 227 DI 10.1002/syn.890120307 PG 8 WC Neurosciences SC Neurosciences & Neurology GA JR703 UT WOS:A1992JR70300006 PM 1481141 ER PT J AU FOWLER, JS VOLKOW, ND LOGAN, J MACGREGOR, RR WANG, GJ WOLF, AP AF FOWLER, JS VOLKOW, ND LOGAN, J MACGREGOR, RR WANG, GJ WOLF, AP TI ALCOHOL-INTOXICATION DOES NOT CHANGE [C-11] COCAINE PHARMACOKINETICS IN HUMAN BRAIN AND HEART SO SYNAPSE LA English DT Article DE PET; COCAINE DISTRIBUTION; COCAINE CLEARANCE; COCAETHYLENE ID POSITRON EMISSION TOMOGRAPHY; COCAINE ABUSE; MYOCARDIAL ISCHEMIA; INTRAVENOUS COCAINE; ETHANOL; COCAETHYLENE; AMPHETAMINE; COMPLICATIONS; CONCURRENT; MECHANISMS AB There is increasing evidence that the combined use of cocaine and alcohol produces enhanced behavioral and toxic effects. We have used PET and tracer doses of [C-11]cocaine in 7 normal human volunteers to assess if the distribution and clearance of cocaine are altered by alcohol intoxication. Each subject received 2 PET studies with [C-11]cocaine (3-11 mug), one before and one during alcohol intoxication (1 g/kg). Regions of interest included the brain (n = 3) and heart (n = 4). Arterial plasma was assayed for unchanged cocaine and for labeled cocaethylene, a metabolite of cocaine found in individuals using cocaine and alcohol in combination (Hearn et al., 1991a). Alcohol intoxication did not change uptake and clearance or the steady-state distribution volume of [C-11] cocaine in brain (striatum, thalamus, and cerebellum) or in heart. Moreover, labeled cocaethylene was not detected in the 10 minute plasma sample. These results suggest that the acute enhancement of behavior and toxicity associated with the combined use of cocaine and alcohol is not due to an alteration in cocaine's organ distribution or to cocaethylene formation but may be related to an additive effect resulting from the direct actions of each of these drugs. C1 BROOKHAVEN NATL LAB, DEPT MED, UPTON, NY 11973 USA. RP BROOKHAVEN NATL LAB, DEPT CHEM, UPTON, NY 11973 USA. FU NIDA NIH HHS [DA 06278]; NINDS NIH HHS [NS 15638] NR 68 TC 20 Z9 20 U1 3 U2 4 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0887-4476 EI 1098-2396 J9 SYNAPSE JI Synapse PD NOV PY 1992 VL 12 IS 3 BP 228 EP 235 DI 10.1002/syn.890120308 PG 8 WC Neurosciences SC Neurosciences & Neurology GA JR703 UT WOS:A1992JR70300007 PM 1481142 ER PT J AU BAKER, JG AF BAKER, JG TI THE PHD LABOR-MARKET IN THE YEAR 2000 TECHNICAL REQUIREMENTS AND PUBLIC-POLICY SO TECHNOLOGICAL FORECASTING AND SOCIAL CHANGE LA English DT Article AB Four Ph. D. labor market models that employ different approaches and assumptions are critically examined; they all project to varying degrees a deterioration in the relationship between new Ph.D.s and job openings around the year 2000. A key assumption in these models is the future rate of R&D spending. If R&D spending continues to grow at its current rate, it is likely that there will be intensified competition between employers for Ph.D.s driving real scientist wages up and reducing the use of Ph.D.s in some activities. Policy actions to mitigate these potential costs include increasing graduate student support, tapping into the postdoctoral pool, and increasing usage of foreign national scientists. RP BAKER, JG (reprint author), OAK RIDGE INST SCI & EDUC,DIV SCI ENGN & EDUC,POB 117,OAK RIDGE,TN 37831, USA. NR 17 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 0040-1625 J9 TECHNOL FORECAST SOC JI Technol. Forecast. Soc. Chang. PD NOV PY 1992 VL 42 IS 3 BP 261 EP 272 DI 10.1016/0040-1625(92)90035-R PG 12 WC Business; Planning & Development SC Business & Economics; Public Administration GA JU481 UT WOS:A1992JU48100003 ER PT J AU BLOW, LE AF BLOW, LE TI HIGHWAYS IN TRANSITION SO TECHNOLOGY REVIEW LA English DT Letter RP BLOW, LE (reprint author), ARGONNE NATL LAB,CTR TRANSPORTAT RES,ARGONNE,IL 60439, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU MASS INST TECHNOL PI CAMBRIDGE PA CAMBRIDGE, MA 02139 SN 0040-1692 J9 TECHNOL REV JI Technol. Rev. PD NOV-DEC PY 1992 VL 95 IS 8 BP 8 EP 8 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JU985 UT WOS:A1992JU98500002 ER PT J AU SCHMOYER, RL AF SCHMOYER, RL TI ASYMPTOTICALLY VALID PREDICTION INTERVALS FOR LINEAR-MODELS SO TECHNOMETRICS LA English DT Article DE ANALYSIS OF VARIANCE; CALIBRATION; DISTRIBUTION-FREE; NONPARAMETRIC; REGRESSION ID REGRESSION AB For estimating the parameters of a linear model, whether by least squares or many robust alternatives, one can use confidence limits that are based on large-sample normal approximations. These limits are asymptotically valid for a wide range of error distributions. Unfortunately. asymptotic validity does not automatically hold for prediction limits for a new observation. because they depend on both parameter estimates and the underlying error distribution. Resampling methods provide prediction limits that are asymptotically valid, but they tend to be computationally intensive, especially when used with robust estimators. This article presents alternative prediction limits that are asymptotically valid, are not based on resampling. and are computationally more tractable than methods that are. They are based on quantiles of a convolution of the empirical distribution of the residuals and the limiting normal distribution of the parameter estimates. Simulations suggest that the proposed limits perform reasonably and are comparable to limits based on resampling. RP SCHMOYER, RL (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 10 TC 8 Z9 8 U1 3 U2 4 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD NOV PY 1992 VL 34 IS 4 BP 399 EP 408 DI 10.2307/1268939 PG 10 WC Statistics & Probability SC Mathematics GA JU485 UT WOS:A1992JU48500002 ER PT J AU ERICKSEN, RH DAVIS, AC WARREN, WE AF ERICKSEN, RH DAVIS, AC WARREN, WE TI DEFLECTION-FORCE MEASUREMENTS AND OBSERVATIONS ON KEVLAR-29(R) PARACHUTE FABRICS SO TEXTILE RESEARCH JOURNAL LA English DT Article AB Deflection-force relations for plain weave Kevlar(R) fabrics have been determined under conditions of uniaxial loading. In these experiments, the loading is stopped at a given level and a portion of the fabric is encapsulated. The fabric is then unloaded, sectioned, and photographed. Measurements on the photographs reveal the changes in weave geometry and yam cross section with loading. The initial geometrical data are used in a large deformation mechanical model, which couples yam bending and stretching effects to predict theoretical displacement-force relations for the fabric. Experimental and theoretical deflection-force curves are in good agreement; they show that during initial loading the response is dominated by yam bending, while for large loads the response is dominated by yarn stretching. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. NR 12 TC 7 Z9 7 U1 1 U2 1 PU TEXTILE RESEARCH INST PI PRINCETON PA PO BOX 625, PRINCETON, NJ 08540 SN 0040-5175 J9 TEXT RES J JI Text. Res. J. PD NOV PY 1992 VL 62 IS 11 BP 628 EP 637 PG 10 WC Materials Science, Textiles SC Materials Science GA JW468 UT WOS:A1992JW46800002 ER PT J AU HALES, LS BELK, MC AF HALES, LS BELK, MC TI VALIDATION OF OTOLITH ANNULI OF BLUEGILLS IN A SOUTHEASTERN THERMAL RESERVOIR SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Note AB Opaque bands on otoliths were validated as annuli for bluegills Lepomis macrochirus throughout their lives in Par Pond, a nuclear reactor cooling reservoir in South Carolina. Whole mounts of otoliths were suitable for age determination of young bluegills (less than 5 years old), but both whole mounts and otolith sections were necessary for age determination of older bluegills. Marginal increment analyses indicated that annulus formation began as early as February and was complete by June in bluegills of ages 1-9. Annulus formation began earlier in younger (age 1-2) bluegills than in older individuals. Similarity of observed and back-calculated sizes at age supported identification of opaque bands as annuli. Input of warm water from reactor operation occasionally produced opaque bands (false annuli) on otoliths; however, the faintness and incompleteness of such bands clearly distinguished them from true annuli. Identification of the first annulus of some otoliths was problematic due to the occurrence of two types-opaque and translucent-of otolith center (incremental area around the primordium extending out to the first contrasting band). Use of daily otolith increments established that opaque otolith centers were not annuli. Bluegills with opaque otolith centers hatched during the period of annulus formation and were about 1 month older on average than bluegills with translucent otolith centers, which hatched after the period of annulus formation. Comparison of growth rates in Par Pond and elsewhere, though complicated by other researchers' use of scale information, suggests that errors in age determination were unlikely. This study extends previous research into validating annuli of bluegill otoliths to older fish and confirms the utility of otolith information for age assessment of another centrarchid species. C1 UNIV GEORGIA,DEPT ZOOL,ATHENS,GA 30602. UNIV GEORGIA,INST ECOL,ATHENS,GA 30602. SAVANNAH RIVER ECOL LAB,AIKEN,SC 29801. UNIV GEORGIA,DEPT ZOOL,ATHENS,GA 30602. NR 23 TC 12 Z9 12 U1 2 U2 5 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD NOV PY 1992 VL 121 IS 6 BP 823 EP 830 DI 10.1577/1548-8659(1992)121<0823:VOOAOB>2.3.CO;2 PG 8 WC Fisheries SC Fisheries GA KR622 UT WOS:A1992KR62200017 ER PT J AU APPELBAUM, FR MATTHEWS, DC EARY, JF BADGER, CC KELLOGG, M PRESS, OW MARTIN, PJ FISHER, DR NELP, WB THOMAS, ED BERNSTEIN, ID AF APPELBAUM, FR MATTHEWS, DC EARY, JF BADGER, CC KELLOGG, M PRESS, OW MARTIN, PJ FISHER, DR NELP, WB THOMAS, ED BERNSTEIN, ID TI THE USE OF RADIOLABELED ANTI-CD33 ANTIBODY TO AUGMENT MARROW IRRADIATION PRIOR TO MARROW TRANSPLANTATION FOR ACUTE MYELOGENOUS LEUKEMIA SO TRANSPLANTATION LA English DT Article ID ACUTE MYELOID-LEUKEMIA; MONOCLONAL-ANTIBODIES; RANDOMIZED TRIAL; LYMPHOMA; ANTIGEN; CELLS; RADIONUCLIDE; PRECURSORS; EXPRESSION; REGIMENS AB Disease recurrence remains a major limitation to the use of marrow transplantation to treat leukemia. Previous transplant studies have demonstrated that higher doses of total-body irradiation result in less disease recurrence, but more toxicity. In this study, the possibility of delivering radiotherapy specifically to marrow using a radiolabeled anti-CD33 antibody (p67) was explored. Biodistribution studies were performed in nine patients using.05-.5 mg/kg p67 trace-labeled with I-131. In most patients initial specific uptake of I-131-p67 in the marrow was seen, but the half-life of the radiolabel in the marrow space was relatively brief, ranging from 9-41 hr, presumably due to modulation of the I-131-p67-CD33 complex with subsequent digestion and release of I-131 from the marrow space. In four of nine patients these biodistribution studies demonstrated that with I-131-p67 marrow and spleen would receive more radiation than any normal nonhematopoietic organ, and therefore these four patients were treated with 110-330 mCi I-131 conjugated to p67 followed by a standard transplant regimen of cyclophosphamide plus 12 Gy TBI. All four patients tolerated the procedure well and three of the four are alive in remission 195-477 days posttransplant. This study demonstrates the feasibility of using a radiolabeled antimyeloid antibody as part of a marrow transplant preparative regimen and also highlights a major limitation of using conventionally labeled anti-CD33-namely, the short residence time in marrow. Strategies to overcome this limitation include the use of alternative labeling techniques or the selection of cell surface stable antigens as targets. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. UNIV WASHINGTON, DEPT MED, DIV ONCOL, SEATTLE, WA 98195 USA. UNIV WASHINGTON, DEPT RADIOL, DIV NUCL MED, SEATTLE, WA 98195 USA. UNIV WASHINGTON, DEPT PEDIAT HEMATOL ONCOL, SEATTLE, WA 98195 USA. RP APPELBAUM, FR (reprint author), FRED HUTCHINSON CANC RES CTR, ROOM M318, 1124 COLUMBIA ST, SEATTLE, WA 98104 USA. FU NCI NIH HHS [CA 44991, CA 18105, CA 18029] NR 21 TC 108 Z9 110 U1 0 U2 0 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 0041-1337 J9 TRANSPLANTATION JI Transplantation PD NOV PY 1992 VL 54 IS 5 BP 829 EP 833 DI 10.1097/00007890-199211000-00012 PG 5 WC Immunology; Surgery; Transplantation SC Immunology; Surgery; Transplantation GA JY228 UT WOS:A1992JY22800012 PM 1440849 ER PT J AU JOY, DC PAWLEY, JB AF JOY, DC PAWLEY, JB TI HIGH-RESOLUTION SCANNING ELECTRON-MICROSCOPY SO ULTRAMICROSCOPY LA English DT Article ID FREEZE-SUBSTITUTION; SCATTERING; DECORATION; CONTRAST; SURFACE; IMAGES; FILMS; CELLS; THIN; SEM AB The spatial resolution of the scanning electron microscope is limited by at least three factors: the diameter of the electron probe, the size and shape of the beam/specimen interaction volume with the solid for the mode of imaging employed and the Poisson statistics of the detected signal. Any practical consideration of the high-resolution performance of the SEM must therefore also involve a knowledge of the contrast available from the signal producing the image and the radiation sensitivity of the specimen. With state-of-the-art electron optics, resolutions of the order of 1 nm are now possible. The optimum conditions for achieving such performance with the minimum radiation damage to the specimen correspond to beam energies in the range 1-3 keV. Progress beyond this level may be restricted by the delocalization of SE production and ultimate limits to electron-optical performance. C1 OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. UNIV WISCONSIN, IMR, MADISON, WI 53706 USA. RP JOY, DC (reprint author), UNIV TENNESSEE, EM FACIL, KNOXVILLE, TN 37996 USA. FU NCRR NIH HHS [DRR-570] NR 112 TC 49 Z9 51 U1 0 U2 23 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 EI 1879-2723 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD NOV PY 1992 VL 47 IS 1-3 BP 80 EP 100 DI 10.1016/0304-3991(92)90186-N PG 21 WC Microscopy SC Microscopy GA KE825 UT WOS:A1992KE82500007 PM 1481281 ER PT J AU WILLIAMS, DB MICHAEL, JR GOLDSTEIN, JI ROMIG, AD AF WILLIAMS, DB MICHAEL, JR GOLDSTEIN, JI ROMIG, AD TI DEFINITION OF THE SPATIAL-RESOLUTION OF X-RAY-MICROANALYSIS IN THIN FOILS SO ULTRAMICROSCOPY LA English DT Article ID ANALYTICAL ELECTRON-MICROSCOPE AB The spatial resolution of X-ray microanalysis in thin foils is defined in terms of the incident electron beam diameter and the average beam broadening. The beam diameter is defined as the full width tenth maximum of a Gaussian intensity distribution. The spatial resolution is calculated by a convolution of the beam diameter and the average beam broadening. This definition of the spatial resolution can be related simply to experimental measurements of composition profiles across interphase interfaces. Monte Carlo calculations using a high-speed parallel supercomputer show good agreement with this definition of the spatial resolution and calculations based on this definition. The agreement is good over a range of specimen thicknesses and atomic number, but is poor when excessive beam tailing distorts the assumed Gaussian electron intensity distributions. Beam tailing occurs in low-Z materials because of fast secondary electrons and in high-Z materials because of plural scattering. C1 SANDIA NATL LABS,MAT & PROC SCI DIRECTORATE,ALBUQUERQUE,NM 87185. RP WILLIAMS, DB (reprint author), LEHIGH UNIV,DEPT MAT SCI & ENGN,BETHLEHEM,PA 18015, USA. NR 19 TC 35 Z9 35 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD NOV PY 1992 VL 47 IS 1-3 BP 121 EP 132 DI 10.1016/0304-3991(92)90189-Q PG 12 WC Microscopy SC Microscopy GA KE825 UT WOS:A1992KE82500010 ER PT J AU GLAESER, RM DOWNING, KH AF GLAESER, RM DOWNING, KH TI ASSESSMENT OF RESOLUTION IN BIOLOGICAL ELECTRON CRYSTALLOGRAPHY SO ULTRAMICROSCOPY LA English DT Article AB The resolution of images or density maps produced by electron microscopy and electron crystallography can be objectively defined in terms of the spatial frequency of the highest resolution diffraction spot, or Fourier coefficient, included in the data processing. In practice, this objective definition of resolution is expected to be too optimistic if the amplitudes of the highest resolution structure factors are too weak, if the population of high resolution reflections is too sparse, or if the signal-to-noise ratio of the high resolution data is too low. Calculated examples are presented here which illustrate how the apparent resolution in images of a membrane protein, bacteriorhodopsin, can be reduced from a nominal value of 3.5 angstrom by weak amplitudes, sparse data or high noise levels. These calculations provide concrete examples which can serve as a guide when estimating whether the objective definition of image resolution is likely to correspond to a practical, structurally useful estimate of image resolution. C1 LAWRENCE BERKELEY LAB,DIV CELL & MOLEC BIOL,BERKELEY,CA 94720. RP GLAESER, RM (reprint author), UNIV CALIF BERKELEY,STANLEY DONNER ASU,DEPT MOLEC & CELL BIOL,BERKELEY,CA 94720, USA. FU NIGMS NIH HHS [GM 36884] NR 7 TC 27 Z9 30 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD NOV PY 1992 VL 47 IS 1-3 BP 256 EP 265 DI 10.1016/0304-3991(92)90201-T PG 10 WC Microscopy SC Microscopy GA KE825 UT WOS:A1992KE82500022 PM 1481279 ER PT J AU OKEEFE, MA AF OKEEFE, MA TI RESOLUTION IN HIGH-RESOLUTION ELECTRON-MICROSCOPY SO ULTRAMICROSCOPY LA English DT Article ID IMAGES; ILLUMINATION AB In the field of high-resolution transmission electron microscopy (HRTEM), the term ''resolution'' has come to hold a number of different meanings [M.A. O'Keefe and J.C.H. Spence, in: Proc. 49th Annual EMSA Meeting, p. 498]. The present work reviews the various definitions of HRTEM resolution, derives theoretical expressions for resolution, and suggests how high resolutions may be attained in practice. RP OKEEFE, MA (reprint author), LAWRENCE BERKELEY LAB,NATL CTR ELECTRON MICROSCOPY,BERKELEY,CA 94720, USA. NR 30 TC 70 Z9 70 U1 3 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD NOV PY 1992 VL 47 IS 1-3 BP 282 EP 297 DI 10.1016/0304-3991(92)90203-V PG 16 WC Microscopy SC Microscopy GA KE825 UT WOS:A1992KE82500024 ER PT J AU KAZMERSKI, LL AF KAZMERSKI, LL TI ATOMIC-LEVEL IMAGING, PROCESSING AND CHARACTERIZATION OF DEFECTS AND SURFACES USING PROXIMAL PROBE TECHNIQUES SO VACUUM LA English DT Article; Proceedings Paper CT INTERNATIONAL SYMP ON VACUUM SCIENCE, THIN FILM AND SURFACE SCIENCE ( ISVTS 91 ) CY SEP 16-18, 1991 CL WUXI, PEOPLES R CHINA SP FUDAN UNIV, JIANGNAN UNIV, WUXI BUR FOREIGN AFFAIRS ID SCANNING-TUNNELING-MICROSCOPE; TUNNELLING MICROSCOPE; NANOMETER-SCALE; SILICON; MANIPULATION; CUINSE2; STM AB A new proximal probe technique is introduced for the manipulation and placement of atoms at specific sites on semiconductor surfaces. This study reports the effects of removing single intrinsic atoms and placing extrinsic atoms at predetermined sites at grain boundaries in CulnSe2. The method uses coordinated electronic and wavelength-specific photon fields to reduce the effective tunnelling barrier heights controlling the field evaporation process. A specially developed scanning tunnelling microscope (STM) tip is used for the confinement and direction of the extrinsic atomic species to the surface region. A proximal probe-based electrical characterization technique is used to evaluate and compare the minority-carrier characteristics in the vicinity of the defects before and after the atomic processing. RP KAZMERSKI, LL (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 25 TC 11 Z9 11 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0042-207X J9 VACUUM JI Vacuum PD NOV PY 1992 VL 43 IS 11 BP 1011 EP 1017 DI 10.1016/0042-207X(92)90319-R PG 7 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA JR125 UT WOS:A1992JR12500002 ER PT J AU VANCE, VB MOORE, D TURPEN, TH BRACKER, A HOLLOWELL, VC AF VANCE, VB MOORE, D TURPEN, TH BRACKER, A HOLLOWELL, VC TI THE COMPLETE NUCLEOTIDE-SEQUENCE OF PEPPER MOTTLE VIRUS GENOMIC RNA - COMPARISON OF THE ENCODED POLYPROTEIN WITH THOSE OF OTHER SEQUENCED POTYVIRUSES SO VIROLOGY LA English DT Article ID HELPER COMPONENT; ESCHERICHIA-COLI; CLEAVAGE SITE; MUTATIONAL ANALYSIS; 49-KDA PROTEINASE; N-TERMINUS; IDENTIFICATION; INVITRO; PLANT; VPG C1 BIOSOURCE GENET CORP,VACAVILLE,CA 95688. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP VANCE, VB (reprint author), UNIV S CAROLINA,DEPT BIOL SCI,COLUMBIA,SC 29208, USA. NR 38 TC 64 Z9 66 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 0042-6822 J9 VIROLOGY JI Virology PD NOV PY 1992 VL 191 IS 1 BP 19 EP 30 DI 10.1016/0042-6822(92)90162-I PG 12 WC Virology SC Virology GA JT446 UT WOS:A1992JT44600003 PM 1413501 ER PT J AU MARTINEZ, MJ DYKHUIZEN, RC EATON, RR AF MARTINEZ, MJ DYKHUIZEN, RC EATON, RR TI THE APPARENT CONDUCTIVITY FOR STEADY UNSATURATED FLOW IN PERIODICALLY FRACTURED POROUS-MEDIA SO WATER RESOURCES RESEARCH LA English DT Article ID EXCLUSION PROBLEM; TRANSPORT; CAVITIES; SOLUTES; SEEPAGE AB The influence of horizontal fractures on the steady seepage of moisture in variably saturated porous media is analyzed by analytical and numerical means. The fractures are assumed to contain many open (dry) regions, and to be distributed periodically in two dimensions. The dry regions of the fracture form a barrier to moisture flow through the geologic medium. An idealized two-dimensional model that maximizes the barrier effect of the fractures is analyzed. The results of the analysis quantify the effect of the dry regions of the fractures on global water flow through the fractured medium. An apparent conductivity is determined such that the fractured system can be replaced by a homogeneous medium for describing steady unsaturated flow. An asymptotic analysis yields an analytic expression for the apparent hydraulic conductivity through such a system in the limit of small sorptive number (fracture spacing divided by a characteristic capillary suction) for the intact matrix material. The apparent hydraulic conductivity for arbitrary spacing and sorptive number is determined by numerical means. The numerical model accounts for variable hydraulic conductivity as a function of the local pressure head, whereas the asymptotic solution represents the limit of constant conductivity. The numerical results confirm the analytical solution as a lower bound on the apparent hydraulic conductivity. RP MARTINEZ, MJ (reprint author), SANDIA NATL LABS,CTR ENGN SCI,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 19 TC 4 Z9 4 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD NOV PY 1992 VL 28 IS 11 BP 2879 EP 2887 DI 10.1029/92WR01682 PG 9 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA JW482 UT WOS:A1992JW48200001 ER PT J AU BENTLEY, AE MARBURGER, SJ AF BENTLEY, AE MARBURGER, SJ TI ARC-WELDING PENETRATION CONTROL USING QUANTITATIVE FEEDBACK THEORY SO WELDING JOURNAL LA English DT Article AB A feedback control system has been developed for arc weld penetration control. The feedback signal is obtained by measuring the amount of visible and near-infrared light emitted from the backside of the weld. The system is sensitive enough to use a fiberoptic cable for transmitting the light from the weld to the sensor. This facilitates welding assemblies with limited access to the underside of the weld. Welds of constant joint penetration (underbead width) have been demonstrated in tests with travel speeds varying from 1.5 to 6 in./min (0.64-2.54 mm/s), and with 200% changes in part thickness. The system also compensates for sharp discontinuities in heat sinking and arc length. Quantitative feedback theory (QFT) was used to design the control laws. RP BENTLEY, AE (reprint author), SANDIA NATL LABS,DIV PROC DEV & FABRICAT,LIVERMORE,CA 94550, USA. NR 8 TC 11 Z9 11 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA PO BOX 351040, MIAMI, FL 33135 SN 0043-2296 J9 WELD J JI Weld. J. PD NOV PY 1992 VL 71 IS 11 BP S397 EP S405 PG 9 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA JW339 UT WOS:A1992JW33900011 ER PT J AU VITEK, JM DAVID, SA SIKKA, VK AF VITEK, JM DAVID, SA SIKKA, VK TI EXAMINATION OF TYPE-308 AND TYPE-308CRE STAINLESS-STEELS AFTER INTERRUPTED CREEP TESTING SO WELDING JOURNAL LA English DT Article DE 308 STAINLESS STEEL; 308CRE STAINLESS STEEL; CREEP PROPERTIES; MICROSTRUCTURE; PRECIPITATION BEHAVIOR; GTA; HOMOGENIZED CONDITION; INTERGRANULAR CRACKS; FRACTURE BEHAVIOR; CREEP DUCTILITY ID BEHAVIOR AB Interrupted creep tests were performed at 650-degrees-C on Types 308 and 308CRE (Controlled Residual Elements) material in both the homogenized and as-welded conditions. The microstructures were evaluated in order to determine the mechanism by which CRE additions, and specifically titanium additions, improve the elevated-temperature creep properties of Type 308 stainless steel. The Ti-modified Type 308 stainless steel exhibits a considerably lower steady-state creep rate, which results in a longer rupture life. In addition, the modified material has a more uniform distribution of Precipitates than the unmodified alloy, and the continuous network of carbides found in the unmodified Type 308 steel along grain boundaries (homogenized material) or the ferrite/austenite interfaces (weld material) is avoided. This continuous network in the Type 308 steel provides sites for the nucleation of extensive intergranular cracks during tertiary creep. RP VITEK, JM (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN, USA. NR 24 TC 5 Z9 5 U1 0 U2 1 PU AMER WELDING SOC PI MIAMI PA PO BOX 351040, MIAMI, FL 33135 SN 0043-2296 J9 WELD J JI Weld. J. PD NOV PY 1992 VL 71 IS 11 BP S421 EP S435 PG 15 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA JW339 UT WOS:A1992JW33900013 ER PT J AU BACHLER, J BARTKE, J BIALKOWSKA, H BOCK, R BROCKMANN, R BUNCIC, P CHASE, SI DERADO, I ECKARDT, V ESCHKE, J FERENC, D FLEISCHMANN, B FUCHS, M GAZDZICKI, M GEBAUER, HJ GLADYSZ, E HARRIS, JW HECK, W HOFFMANN, M KABANA, S KADIJA, K KEIDEL, R KOSIEC, J KOWALSKI, M KUHMICHEL, A LAHANAS, M LEE, Y LEVINE, M LJUBICIC, A MARGETIS, S NAPPI, E ODYNIEC, G PAIC, G PANAGIOTOU, AD PETRIDIS, A PFENNIG, J PIPER, A POSA, F PUGH, HG PUHLHOFER, F RAI, G RAUCH, W RENFORDT, R ROHRICH, D ROTHARD, H RUNGE, K SANDOVAL, A SCHMIDT, E SCHMITZ, N SCHMOETTEN, E SCHNEIDER, I SEYBOTH, P SEYERLEIN, J SKRZYPCZAK, E STEFANSKI, P STOCK, R STROBELE, H TEITELBAUM, L TONSE, S VASSILEIADIS, G VESZTERGOMBI, G VRANIC, D WENIG, S AF BACHLER, J BARTKE, J BIALKOWSKA, H BOCK, R BROCKMANN, R BUNCIC, P CHASE, SI DERADO, I ECKARDT, V ESCHKE, J FERENC, D FLEISCHMANN, B FUCHS, M GAZDZICKI, M GEBAUER, HJ GLADYSZ, E HARRIS, JW HECK, W HOFFMANN, M KABANA, S KADIJA, K KEIDEL, R KOSIEC, J KOWALSKI, M KUHMICHEL, A LAHANAS, M LEE, Y LEVINE, M LJUBICIC, A MARGETIS, S NAPPI, E ODYNIEC, G PAIC, G PANAGIOTOU, AD PETRIDIS, A PFENNIG, J PIPER, A POSA, F PUGH, HG PUHLHOFER, F RAI, G RAUCH, W RENFORDT, R ROHRICH, D ROTHARD, H RUNGE, K SANDOVAL, A SCHMIDT, E SCHMITZ, N SCHMOETTEN, E SCHNEIDER, I SEYBOTH, P SEYERLEIN, J SKRZYPCZAK, E STEFANSKI, P STOCK, R STROBELE, H TEITELBAUM, L TONSE, S VASSILEIADIS, G VESZTERGOMBI, G VRANIC, D WENIG, S TI FLUCTUATIONS OF MULTIPLICITIES IN RAPIDITY WINDOWS IN SULFUR-SULFUR COLLISIONS AT 200 A-GEV SO ZEITSCHRIFT FUR PHYSIK C-PARTICLES AND FIELDS LA English DT Article ID ENERGY NUCLEAR COLLISIONS; HEAVY-ION COLLISIONS; CHARGED-PARTICLE MULTIPLICITIES; DISTRIBUTIONS; DEPENDENCE AB Multiplicity distributions and their second moments for negatively charged particles produced in S-32 - S central and minimum bias interactions at 200 A GeV are studied in various rapidity intervals. Fritiof and Venus models mostly describe the dependence of second moments on rapidity intervals in minimum bias interactions, but not in central collisions. For central collisions the behaviour of second moments might indicate enhanced multiplicity fluctuations. C1 UNIV BARI,DIPARTIMENTO FIS,I-70124 BARI,ITALY. INFN,BARI,ITALY. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. CERN,CH-1211 GENEVA 23,SWITZERLAND. INST NUCL PHYS,PL-31342 KRAKOW,POLAND. GESELL SCHWERIONENFORSCH GMBH,W-6100 DARMSTADT 11,GERMANY. UNIV FRANKFURT,FACHBEREICH PHYS,W-6000 FRANKFURT 1,GERMANY. UNIV FREIBURG,FAK PHYS,W-7800 FREIBURG,GERMANY. UNIV MARBURG,FACHBEREICH PHYS,W-3550 MARBURG,GERMANY. MAX PLANCK INST PHYS & ASTROPHYS,W-8000 MUNICH 40,GERMANY. UNIV WARSAW,INST EXPTL PHYS,PL-00325 WARSAW,POLAND. INST NUCL STUDIES,WARSAW,POLAND. RUDJER BOSKOVIC INST,YU-41001 ZAGREB,YUGOSLAVIA. RP BACHLER, J (reprint author), UNIV ATHENS,DEPT PHYS,ATHENS,GREECE. NR 29 TC 10 Z9 11 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0170-9739 J9 Z PHYS C PART FIELDS JI Z. Phys. C-Part. Fields PD NOV PY 1992 VL 56 IS 3 BP 347 EP 354 PG 8 WC Physics, Particles & Fields SC Physics GA JZ079 UT WOS:A1992JZ07900002 ER PT J AU DAYON, M RAPPOPORT, V SMIRNITSKY, V AMMAR, R AMMOSOV, V BAKICH, A BARANOV, V BATUSOV, Y BUNYATOV, S BURNETT, T COPPAGE, D DAVIS, R EGOROV, O GAPIENKO, V GORITCHEV, P GRESS, J IVANOVA, M JURAK, A KLUKHIN, V KOLGANOVA, E KORESHEV, V KRZYWDZINSKI, S KUZNETSOV, O KWAK, N LORD, J LYUKOV, V OLSZEWSKI, A PEAK, L PITUKHIN, P POZHAROVA, E RIEMER, R ROSENBLADT, R RUBIN, H SHAMANOV, V SIROTENKO, V SMART, W STUMP, R TCHERNEV, H VOYVODIC, L WILCZYNSKA, B WILCZYNSKI, H WILKES, R WOLTER, W WOSIEK, B AF DAYON, M RAPPOPORT, V SMIRNITSKY, V AMMAR, R AMMOSOV, V BAKICH, A BARANOV, V BATUSOV, Y BUNYATOV, S BURNETT, T COPPAGE, D DAVIS, R EGOROV, O GAPIENKO, V GORITCHEV, P GRESS, J IVANOVA, M JURAK, A KLUKHIN, V KOLGANOVA, E KORESHEV, V KRZYWDZINSKI, S KUZNETSOV, O KWAK, N LORD, J LYUKOV, V OLSZEWSKI, A PEAK, L PITUKHIN, P POZHAROVA, E RIEMER, R ROSENBLADT, R RUBIN, H SHAMANOV, V SIROTENKO, V SMART, W STUMP, R TCHERNEV, H VOYVODIC, L WILCZYNSKA, B WILCZYNSKI, H WILKES, R WOLTER, W WOSIEK, B TI BACKWARD EMITTED PROTONS IN INTERACTIONS OF NEUTRINOS WITH NUCLEI IN PHOTOEMULSION SO ZEITSCHRIFT FUR PHYSIK C-PARTICLES AND FIELDS LA English DT Article ID E-564 AB Backward emitted protons with momentum p > 0.3 GeV/c in interactions of neutrino in the energy range 10-200 GeV with photoemulsion nuclei were investigated. Energy spectrum slope parameter of backward protons was measured to be T0 = 48.9 +/- 7.9 MeV. The A-dependence power index of relative mean yield of backward protons was found to be a = 0.68 +/- 0.12. A drop in the mean yield of backward protons at the four momentum squared over approximately 15 (GeV/c)2 (the neutrino energy over approximately 50 GeV) was observed. C1 UNIV KANSAS, LAWRENCE, KS 66045 USA. SERPUKHOV HIGH ENERGY PHYS INST, SERPUKHOV, USSR. UNIV SYDNEY, SYDNEY, NSW 2006, AUSTRALIA. DUBNA JOINT NUCL RES INST, DUBNA, USSR. UNIV WASHINGTON, SEATTLE, WA 98195 USA. INST THEORET & EXPTL PHYS, MOSCOW, USSR. PAISIJ HILENDARSKI UNIV PLOVDIV, PLOVDIV, BULGARIA. INST NUCL PHYS, PL-31342 KRAKOW, POLAND. IIT, CHICAGO, IL 60616 USA. FERMI NATL ACCELERATOR LAB, BATAVIA, IL 60510 USA. INST NUCL ENERGY RES, SOFIA, BULGARIA. RP DAYON, M (reprint author), PN LEBEDEV PHYS INST, LENINSKY PROSPECT 53, MOSCOW 117924, USSR. RI Klyukhin, Vyacheslav/D-6850-2012; Wilkes, R.Jeffrey/E-6011-2013 OI Klyukhin, Vyacheslav/0000-0002-8577-6531; NR 14 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0170-9739 J9 Z PHYS C PART FIELDS JI Z. Phys. C-Part. Fields PD NOV PY 1992 VL 56 IS 3 BP 391 EP 393 DI 10.1007/BF01565946 PG 3 WC Physics, Particles & Fields SC Physics GA JZ079 UT WOS:A1992JZ07900006 ER PT J AU KINGSLEY, DM BLAND, AE GRUBBER, JM MARKER, PC RUSSELL, LB COPELAND, NG JENKINS, NA AF KINGSLEY, DM BLAND, AE GRUBBER, JM MARKER, PC RUSSELL, LB COPELAND, NG JENKINS, NA TI THE MOUSE SHORT-EAR SKELETAL MORPHOGENESIS LOCUS IS ASSOCIATED WITH DEFECTS IN A BONE MORPHOGENETIC MEMBER OF THE TGF-BETA SUPERFAMILY SO CELL LA English DT Article ID TRANSFORMING GROWTH-FACTOR; MESODERM-INDUCING FACTOR; GENETIC-LINKAGE MAP; MESSENGER-RNA; EMBRYONIC-DEVELOPMENT; OSTEOGENIC PROTEIN; PATTERN-FORMATION; RETINOIC ACID; GERM LAYERS; ACTIVIN-A AB The mouse short ear gene is required for normal growth and patterning of skeletal structures, and for repair of bone fractures in adults. We have carried out an extensive chromosome walk in the chromosome region that surrounds this locus. Here we show that the short ear region contains the gene for a TGFbeta-related protein called bone morphogenetic protein 5 (Bmp-5). This gene is deleted or rearranged in several independent mutations at the short ear locus. Mice homozygous for large deletions of the Bmp-5 coding region are viable and fertile. Mutations at the short ear locus provide an important new tool for defining the normal functions of BMPs in mammals. The specific skeletal defects seen in short-eared animals, which occur against a background of otherwise normal skeletal structures, suggest that particular aspects of skeletal morphology may be determined by individual members of a family of signaling factors that can induce the formation of cartilage and bone in vivo. C1 OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. NCI,FREDERICK CANC RES & DEV CTR,MAMMALIAN GENET LAB,ABL BASIC RES PROGRAM,FREDERICK,MD 21702. RP KINGSLEY, DM (reprint author), STANFORD UNIV,MED CTR,SCH MED,DEPT DEV BIOL,BECKMAN CTR B300,STANFORD,CA 94305, USA. FU NCI NIH HHS [N01-CO-74101] NR 66 TC 387 Z9 395 U1 0 U2 6 PU CELL PRESS PI CAMBRIDGE PA 1050 MASSACHUSETTES AVE, CIRCULATION DEPT, CAMBRIDGE, MA 02138 SN 0092-8674 J9 CELL JI Cell PD OCT 30 PY 1992 VL 71 IS 3 BP 399 EP 410 DI 10.1016/0092-8674(92)90510-J PG 12 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA JW435 UT WOS:A1992JW43500007 PM 1339316 ER PT J AU HSU, CW LIAO, CL MA, ZX TJOSSEM, PJH NG, CY AF HSU, CW LIAO, CL MA, ZX TJOSSEM, PJH NG, CY TI A STUDY OF THE S(3P2,1,0 1D2) PRODUCTION IN THE 193 NM PHOTODISSOCIATION OF HS AND H2S SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ULTRAVIOLET PHOTODISSOCIATION; ENERGY-DISTRIBUTION; PHOTO-DISSOCIATION; EXCITED-STATES; CROSS-SECTIONS; 1ST CONTINUUM; SULFUR-ATOMS; SPECTROSCOPY; FLUORESCENCE; DYNAMICS AB The dynamics of the photodissociation processes, HS+hv(193 nm)-->H(2S)+S(3P(J), 1D2) (process (A)) and H2S+hv(193 nm)-->H-2(X)+S(3P(J), 1D2) (process (B)) have been studied using 2+1 resonance-enhanced multiphoton-ionization techniques. By using the rate equation Model and by calibrating the S(3P(J), 1D2) formation from processes (A) and (B) with that from the 193 nm photodissociation of CS2, we have determined the S(3P):S(1D) branching ratios, the fine-structure distributions of S(P-3(2,1,0)), and the absolute cross sections for processes (A) and (B). The branching ratio S(3P):S(1D)=0.87:0.13 observed for process (A) supports the direct photodissociation mechanism for HS at 193 nm via the excited repulsive HS(2SIGMA-, 2DELTA) potential energy surfaces. The fine-structure distribution S(P-3(2)):S(P-3(1)):S(P-3(0))=0.68:0.24:0.08 for process (A) is colder than the statistical distribution. The absolute cross section for process (A) is estimated to be 1.1 x 10(-18) cm2. Process (B), which is estimated to have an absolute cross section of 0.3 x 10(-18) cm2, is minor compared to the formation HS+H in the 193 nm photodissociation of H2S. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. GRINNELL COLL,DEPT PHYS,GRINNELL,IA 50112. NR 35 TC 29 Z9 29 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD OCT 30 PY 1992 VL 199 IS 1-2 BP 78 EP 84 DI 10.1016/0009-2614(92)80052-D PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JV107 UT WOS:A1992JV10700013 ER PT J AU HESKETT, D TANG, D SHI, X TSUEI, KD AF HESKETT, D TANG, D SHI, X TSUEI, KD TI COADSORBATE-INDUCED UNDERPOLARIZATION OF ALKALI OVERLAYERS SO CHEMICAL PHYSICS LETTERS LA English DT Article ID PROMOTED OXIDATION; ELECTRONIC-STRUCTURE; ENHANCED OXIDATION; RU(001) SURFACE; CO-ADSORPTION; NA OVERLAYERS; OXYGEN; POTASSIUM; COADSORPTION; CS AB We have measured the work-function changes induced by the coadsorption of oxygen or carbon monoxide with sodium as a function of alkali precoverage for the systems O2/Na/Cu(111), O2/Na/Ni(111). and CO/Na/Ni(111). In agreement with results for many other related systems, we observe anomalous work-function decreases for initial doses of both O2 and CO for high alkali precoverages. Our data are inconsistent with the standard explanations for these results. We propose a new model in which the work-function changes induced by the coadsorbate involve a combination of coadsorbate dipole moment and coadsorbate-induced undepolarization of the alkali overlayer. C1 BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP HESKETT, D (reprint author), UNIV RHODE ISL,DEPT PHYS,KINGSTON,RI 02881, USA. NR 44 TC 21 Z9 22 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD OCT 30 PY 1992 VL 199 IS 1-2 BP 138 EP 143 DI 10.1016/0009-2614(92)80060-O PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JV107 UT WOS:A1992JV10700021 ER PT J AU KADA, J HEIT, M AF KADA, J HEIT, M TI THE INVENTORIES OF ANTHROPOGENIC PB, ZN, AS, CD, AND THE RADIONUCLIDES CS-137 AND EXCESS PB-210 IN LAKE-SEDIMENTS OF THE ADIRONDACK REGION, USA SO HYDROBIOLOGIA LA English DT Article DE SEDIMENTS; CS-137; PB-210; ADIRONDACK; ANTHROPOGENIC TRACE ELEMENTS; ATMOSPHERIC DEPOSITION ID ONTARIO; CHERNOBYL; TRACERS; FALLOUT; CANADA; RATES AB We determined the inventories of four anthropogenic trace elements, Pb, Zn, As, and Cd, and two radionuclides, Cs-137 and excess Pb-210, in sediment cores collected from eight remote lakes in the Adirondack region of the northeastern United States. The inventories of all six substances vary considerably among the sediment cores, although the lakes and their associated catchments must have received similar cumulative per unit area atmospheric inputs of these substances. These variations are highly correlated, indicating that the trace elements and radionuclides are affected in a coherent way by the processes controlling their deposition to the sediments of these lakes. Assuming that the anthropogenic trace element inventories in each sediment core are enhanced or depleted relative to cumulative atmospheric deposition to the extent indicated by the sediment core inventories of either Cs-137 or excess Pb-210, we produced estimates of the cumulative atmospheric inputs of the four anthropogenic trace elements to this region. Comparison of the excess Pb-210 normalized anthropogenic Pb, Zn, Cd inventories of the Adirondack sediment cores with excess Pb-210 normalized inventories of the same substances In a group of South Central Ontario lakes suggests that the Adirondack region has received greater cumulative anthropogenic inputs of Pb, Zn and Cd by a factor of 1.6, 4.5, and 2.9, respectively. RP KADA, J (reprint author), US DOE,ENVIRONM MEASUREMENTS LAB,NEW YORK,NY 10014, USA. NR 29 TC 37 Z9 37 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD OCT 30 PY 1992 VL 246 IS 3 BP 231 EP 241 DI 10.1007/BF00005700 PG 11 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA KB850 UT WOS:A1992KB85000005 ER PT J AU WHIRLEY, RG HENSHALL, GA AF WHIRLEY, RG HENSHALL, GA TI CREEP DEFORMATION STRUCTURAL-ANALYSIS USING AN EFFICIENT NUMERICAL ALGORITHM SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article ID PLASTICITY AB This paper presents a fast numerical algorithm for the implementation of material models for creep into finite element codes. First, an overview of existing algorithms for transient and steady-state creep is given. Next, a new formulation is presented which reduces the constitutive integration to the solution of a scalar non-linear algebraic equation. A solution is shown to exist without the need for subincrementation. Details of the numerical algorithm are then discussed. The paper closes with several numerical examples which illustrate the speed, robustness and accuracy of the proposed procedure as implemented in the Lawrence Livermore National Laboratory finite element codes NIKE2D and NIKE3D. RP WHIRLEY, RG (reprint author), LAWRENCE LIVERMORE NATL LAB,METHODS DEV GRP,L-122,LIVERMORE,CA 94550, USA. NR 23 TC 8 Z9 8 U1 0 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD OCT 30 PY 1992 VL 35 IS 7 BP 1427 EP 1442 DI 10.1002/nme.1620350704 PG 16 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA JR340 UT WOS:A1992JR34000003 ER PT J AU YANG, SL CHEN, R CLINE, MC NGUYEN, HL MICKLOW, GJ AF YANG, SL CHEN, R CLINE, MC NGUYEN, HL MICKLOW, GJ TI NUMERICAL-SIMULATION OF A LOW-EMISSION GAS-TURBINE COMBUSTOR USING KIVA-II SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS LA English DT Article DE GAS TURBINE COMBUSTORS; CFD; EMISSIONS; AIRBLAST ATOMIZERS; DILUTION JET MIXING ID SPEEDS AB A numerical study was performed to investigate chemically reactive flows with sprays inside a staged turbine combustor (STC) using a modified version of the KIVA-II code. This STC consists of a fuel nozzle (FN), a rich-burn (RB) zone, a converging connecting pipe, a quick-quench (QQ) zone, a diverging connecting pipe and a lean-combustion (LC) zone. From the computational viewpoint, it is more efficient to split the STC into two subsystems, called FN/RB zone and QQ/LC zones, and the numerical solutions were obtained separately for each subsystem. This paper addresses the numerical results of the STC which is equipped with an advanced airblast fuel nozzle. The airblast nozzle has two fuel injection passages and four air flow passages. The input conditions used in this study were chosen similar to those encountered in advanced combustion systems. Preliminary results generated illustrate some of the major features of the flow and temperature fields inside the STC. Velocity, temperature and some critical species information inside the FN/RB zone are given. Formation of the co- and counter-rotating bulk flow and the sandwiched-ring-shaped temperature field, typical of the confined inclined jet-in-cross-flow, can be seen clearly in the QQ/LC zones. The calculations of the mass-weighted standard deviation and the pattern factor of temperature revealed that the mixing performance of the STC is very promising. The temperature of the fluid leaving the LC zone is very uniform. Prediction of the NOx emission shows that there is no excessive thermal NOx produced in the QQ/LC zones for the case studied. From the results obtained so far, it appears that the modified KIVA-II code can be used to guide the low-emission combustion experiments. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. NASA,LEWIS RES CTR,CLEVELAND,OH 44135. UNIV FLORIDA,GAINESVILLE,FL 32611. RP YANG, SL (reprint author), MICHIGAN TECHNOL UNIV,ME-EM DEPT,1400 TOWNSEND DR,HOUGHTON,MI 49931, USA. NR 19 TC 5 Z9 5 U1 1 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0271-2091 J9 INT J NUMER METH FL JI Int. J. Numer. Methods Fluids PD OCT 30 PY 1992 VL 15 IS 8 BP 865 EP 881 DI 10.1002/fld.1650150803 PG 17 WC Computer Science, Interdisciplinary Applications; Mathematics, Interdisciplinary Applications; Mechanics; Physics, Fluids & Plasmas SC Computer Science; Mathematics; Mechanics; Physics GA JU725 UT WOS:A1992JU72500002 ER PT J AU BELYAEV, VM AF BELYAEV, VM TI PARAMETER OF K-MESON MIXING AND NON-ABELIAN ANOMALY SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article AB The amplitude of K meson mixing is calculated. Pseudo-Goldstone fields are considered as phases of gamma5 transformation of quark fields. A formalism for description of K and pi mesons in this approach is given. The amplitude is expressed in terms of matrix elements [0\g(s)sG(munugammanu)d\KBAR] and [0\sgammanugamma5d\KBAR). It is shown that there is a relation between [0\g(s)sG(munugammanu)d\K] and [0\pi/alpha(s)/piG(munu)G(munu)\0]. This relation is in good agreement with known values for amplitudes. The result for the parameter of K meson mixing is B = 1 + 3m1(2)/16pi2 f(K)2 = 1 + 0.16. From general consideration it is shown that the correction to the vacuum factorization hypothesis must be positive. RP BELYAEV, VM (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 0 TC 1 Z9 1 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 OCT 30 PY 1992 VL 7 IS 27 BP 6833 EP 6844 DI 10.1142/S0217751X92003136 PG 12 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA JU895 UT WOS:A1992JU89500006 ER PT J AU SHANTHA, NC NAPOLITANO, GE AF SHANTHA, NC NAPOLITANO, GE TI GAS-CHROMATOGRAPHY OF FATTY-ACIDS SO JOURNAL OF CHROMATOGRAPHY LA English DT Review ID HIGH-ACCURACY; OILS AB Lipids in foods contain a wide variety of fatty acids differing in chain length, degree of unsaturation, position and configuration of double bonds and the presence of special functional groups. Modem capillary gas chromatography offers excellent separation of fatty acids. Fused-silica capillary columns with stationary phases of medium polarity and non-polar methylsilicone stationary phases successfully separate most of the natural fatty acids. Special applications, such as the separation of complex cis-trans fatty acid mixtures and cyclic fatty acids, require particular chromatographic conditions, including the use of very long capillary columns or more polar stationary phases. The derivatization methods for the preparation of fatty acid esters also need to be optimized to obtain accurate quantitative results. This paper reviews the derivatization techniques, capillary columns and stationary phases commonly used in the gas chromatography of fatty acids in food. C1 OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. UNIV TENNESSEE,CTR ENVIRONM BIOTECHNOL,KNOXVILLE,TN 37831. RP SHANTHA, NC (reprint author), UNIV KENTUCKY,DEPT ANIM SCI,FOOD SCI SECT,LEXINGTON,KY 40546, USA. RI Chandrasekaran, Shantha/A-7515-2011 NR 7 TC 108 Z9 110 U1 0 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR PD OCT 30 PY 1992 VL 624 IS 1-2 BP 37 EP 51 DI 10.1016/0021-9673(92)85673-H PG 15 WC Chemistry, Analytical SC Chemistry GA KE610 UT WOS:A1992KE61000005 PM 1494015 ER PT J AU KNIZE, MG FELTON, JS GROSS, GA AF KNIZE, MG FELTON, JS GROSS, GA TI CHROMATOGRAPHIC METHODS FOR THE ANALYSIS OF HETEROCYCLIC AMINE FOOD MUTAGENS CARCINOGENS SO JOURNAL OF CHROMATOGRAPHY LA English DT Review ID FRIED GROUND-BEEF; LIQUID-CHROMATOGRAPHY; MASS-SPECTROMETRY; COOKED MEAT; QUANTIFICATION; PRODUCTS; MEIQX; 2-AMINO-3,8-DIMETHYLIMIDAZO<4,5-F>QUINOXALINE; 2-AMINO-3-METHYLIMIDAZO<4,5-F>QUINOLINE; IDENTIFICATION AB A series of potent heterocyclic amines that are mutagenic and carcinogenic have been discovered that are formed in some heated foods, most notably, meats derived from muscle. Determining the heterocyclic amine content in foods and food products is required for toxicological research, industry quality control, and possibly in the future, regulatory control. The contents of food needs to be determined using reliable analytical techniques. Since heterocyclic amines are present in foods at ng/g levels, a variety of liquid-liquid or solid-phase purification techniques are required, followed by gas or high-performance liquid chromatography. Peak detection has been successful using UV, fluorescence, and mass spectrometric detection, and biological activity using the Ames/Salmonella test. The low levels present require that chromatographic efficiency, and both detector sensitivity and selectivity be optimized. The cartridge solid-phase extraction and high-performance liquid chromatography method have been used to measure the known food-derived heterocyclic amines for several types of food, and to the authors knowledge, this is the only method undergoing intralaboratory comparison and validation. Our analysis of the literature shows that chromatographic analysis of the heterocyclic amines by high-performance liquid chromatography or gas chromatography (with derivatization) is satisfactory for heterocyclic amine analysis in foods although the methods are just now being optimized for routine use. The biggest improvements in speed and accuracy will probably come from improved extraction methods as analysis of complex food samples for heterocyclic amines will always be a challenge. C1 LAWRENCE LIVERMORE NATL LAB,DIV BIOMED SCI,POB 808,LIVERMORE,CA 94551. NESTEC LTD,NESTLE RES CTR,CH-1000 LAUSANNE 26,SWITZERLAND. FU NCI NIH HHS [R01-CA40811, P01-CA55861] NR 28 TC 53 Z9 53 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR PD OCT 30 PY 1992 VL 624 IS 1-2 BP 253 EP 265 DI 10.1016/0021-9673(92)85683-K PG 13 WC Chemistry, Analytical SC Chemistry GA KE610 UT WOS:A1992KE61000015 PM 1494008 ER PT J AU LEDERMAN, L AF LEDERMAN, L TI THE PRE-DRUID SUPER COLLIDER SO SCIENCE LA English DT Letter RP LEDERMAN, L (reprint author), FERMI NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. NR 0 TC 1 Z9 1 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 OCT 30 PY 1992 VL 258 IS 5083 BP 725 EP 725 DI 10.1126/science.258.5083.725 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JV692 UT WOS:A1992JV69200002 PM 17777015 ER PT J AU CAHN, RN AF CAHN, RN TI BIG PHYSICS COLLABORATIONS SO SCIENCE LA English DT Letter RP CAHN, RN (reprint author), LAWRENCE BERKELEY LAB,DIV PHYS,BERKELEY,CA 94720, USA. NR 1 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 OCT 30 PY 1992 VL 258 IS 5083 BP 726 EP 727 DI 10.1126/science.258.5083.726-a PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JV692 UT WOS:A1992JV69200006 PM 17777016 ER PT J AU WANG, J BEDZYK, MJ CAFFREY, M AF WANG, J BEDZYK, MJ CAFFREY, M TI RESONANCE-ENHANCED X-RAYS IN THIN-FILMS - A STRUCTURE PROBE FOR MEMBRANES AND SURFACE-LAYERS SO SCIENCE LA English DT Article ID STANDING WAVES; INTERFACE; FLUORESCENCE; DIFFRACTION AB An x-ray resonance effect in an organic thin film on an x-ray reflecting mirror is reported. The resonance effect is the result of interference between reflected and refracted x-rays at the air-organic thin film interface and occurs at incident angles slightly above the critical angle of the film. In excellent agreement with theory, the primary resonant x-ray electric field that is confined in the organic thin film is approximately 20 times as intense as the electric field of the incident beam when measured at a position close to the center of the film. Resonance-enhanced x-rays can be used to characterize the internal structure of Langmuir-Blodgett thin film membranes. This effect may also find use in x-ray-based thin film devices and in the structural analysis of adlayers and surfaces that have thus far proved difficult, if not impossible, to study because of sensitivity limitations. C1 OHIO STATE UNIV,CHEM PHYS PROGRAM,COLUMBUS,OH 43210. NORTHWESTERN UNIV,DEPT MAT SCI & ENGN,EVANSTON,IL 60208. ARGONNE NATL LAB,ARGONNE,IL 60439. RP WANG, J (reprint author), OHIO STATE UNIV,DEPT CHEM,COLUMBUS,OH 43210, USA. RI Bedzyk, Michael/B-7503-2009; Bedzyk, Michael/K-6903-2013 FU NIDDK NIH HHS [DK 36849, DK 45295] NR 13 TC 111 Z9 113 U1 0 U2 9 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD OCT 30 PY 1992 VL 258 IS 5083 BP 775 EP 778 DI 10.1126/science.1439784 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA JV692 UT WOS:A1992JV69200028 PM 1439784 ER PT J AU CHAUDHURI, J ALYAN, SM JANKOWSKI, AF AF CHAUDHURI, J ALYAN, SM JANKOWSKI, AF TI X-RAY CHARACTERIZATION OF AU/NI MULTILAYER THIN-FILMS SO THIN SOLID FILMS LA English DT Article ID GOLD-NICKEL; SUPERLATTICES; DIFFRACTION AB Au/Ni multilayer thin films of single phase structure were analyzed using kinetmatic X-ray diffraction theories to determine the composition modulation and structure of this multilayer system. The repeat period of the multilayers used in this study ranged from 0.82 x 10(-9) m to 4.26 x 10(-9) m. The composition modulation was found to be a near square wave. The strain at the Au-Ni interface is predicted to be 9.8% at repeat period 1.65 x 10(-9) m with decreasing values above and below this repeat period. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP CHAUDHURI, J (reprint author), WICHITA STATE UNIV,NATL INST AVIAT RES,DEPT MECH ENGN,WICHITA,KS 67208, USA. RI Chaudhuri, Jharna/E-8863-2013 NR 12 TC 9 Z9 9 U1 0 U2 3 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 OCT 30 PY 1992 VL 219 IS 1-2 BP 63 EP 68 DI 10.1016/0040-6090(92)90724-P PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA JZ124 UT WOS:A1992JZ12400010 ER PT J AU BLAU, PJ HABERLIN, CE AF BLAU, PJ HABERLIN, CE TI AN INVESTIGATION OF THE MICROFRICTIONAL BEHAVIOR OF C-60 PARTICLE LAYERS ON ALUMINUM SO THIN SOLID FILMS LA English DT Article ID FRICTION AB Since the discovery of spherical carbon molecules called "buckminsterfullerenes" there has been speculation that they would have unique lubricating properties. An investigation was conducted on the frictional behavior of fullerenes residing as both thick and thin layers on polished aluminum. Stainless steel (type 440C) was used as the slider material. A series of sliding contact experiments was conducted using the friction microprobe, a tribology research instrument developed at Oak Ridge National Labroatory, to measure the friction coefficients of C60 layers applied in two different ways to a polished aluminum alloy surface. Results were compared with the friction of layers of several commerical graphite lubricants applied to the aluminum in the same fashion and to a thick graphite foil material. Under some conditions of powder application, the C60 layers formed thick compacts and had very high friction, and under conditions of wider particulate dispersion, there was no significant difference in friction compared with the uncoated aluminum surface. Scanning electron microscopy was used to study the distribution of materials resulting from sliding contact. RP BLAU, PJ (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,POB 2008,OAK RIDGE,TN 37831, USA. NR 7 TC 52 Z9 54 U1 0 U2 7 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD OCT 30 PY 1992 VL 219 IS 1-2 BP 129 EP 134 DI 10.1016/0040-6090(92)90732-Q PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA JZ124 UT WOS:A1992JZ12400018 ER PT J AU BEHRENS, R BULUSU, S AF BEHRENS, R BULUSU, S TI THERMAL-DECOMPOSITION OF ENERGETIC MATERIALS .3. TEMPORAL BEHAVIORS OF THE RATES OF FORMATION OF THE GASEOUS PYROLYSIS PRODUCTS FROM CONDENSED-PHASE DECOMPOSITION OF 1,3,5-TRINITROHEXAHYDRO-S-TRIAZINE SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID BEAM MASS-SPECTROMETRY; 1,3,5 TRIAZINE RDX; OCTAHYDRO-1,3,5,7-TETRANITRO-1,3,5,7-TETRAZOCINE HMX; MELTING POINT; TEMPERATURES; CHEMISTRY; PRESSURE; FTIR AB Through the use of simultaneous thermogravimetry modulated beam mass spectrometry (STMBMS) measurements, time-of-flight (TOF) velocity-spectra analysis, and H-2, C-13, N-15, and O-18 labeled analogues of 1,3,5-trinitrohexahydro-s-triazine (RDX), the thermal decomposition products of RDX have been identified as H2O, HCN, CO, CH2O, NO, N2O, NH2CHO, NO2, HONO, (CH3)NHCHO, oxy-s-triazine (OST), and 1-nitroso-3,5-dinitrohexahydro-s-triazine (ONDNTA) and all of their gas formation rates have been measured as a function of time. From these results the primary reaction pathways that control the decomposition of RDX in both the solid and liquid phases have been discovered. Four primary reaction pathways control the decomposition of RDX in the liquid phase between 200 and 215-degrees-C. Two pathways are first-order reactions solely in RDX. One produces predominantly OST, NO, and H2O and accounts for approximately 30% of the decomposed RDX, and the other produces predominantly N2O and CH2O with smaller amounts of NO2, CO, and NH2CHO and accounts for 10% of the decomposed RDX. The third pathway consists of formation of ONDNTA by reaction between NO and RDX, followed by the decomposition of ONDNTA to predominantly CH2O and N2O. The fourth reaction pathway consists of decomposition of RDX through reaction with a catalyst that is formed from the decomposition products of previously decomposed RDX. The third and fourth reaction channels each account for approximately 30% of the decomposed RDX. Experiments with solid-phase RDX have shown that its decomposition rate is very much slower than that of liquid-phase RDX. ONDNTA is the only product that appears to be formed during the early stages of the decomposition of RDX in the solid phase. As the solid-phase decomposition progresses, N2O and lesser amounts of CH2O start to evolve and their rates of evolution increase until products associated with the liquid-phase RDX decomposition appear and the rates of gas formation of all products rapidly increase. This behavior strongly suggests that the decomposition of solid RDX occurs through formation of ONDNTA within the lattice, the subsequent decomposition of it within the lattice to N2O and CH2O, followed by the dispersion of CH2O in the RDX, leading to its eventual liquefaction and the onset of the liquid-phase decomposition reactions. C1 USA,ARMAMENT RES,CTR DEV & ENGN,DIV ENERGET MAT,DOVER,NJ 07801. RP BEHRENS, R (reprint author), SANDIA NATL LABS,COMBUST RES FACIL,LIVERMORE,CA 94551, USA. NR 41 TC 86 Z9 86 U1 3 U2 7 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 OCT 29 PY 1992 VL 96 IS 22 BP 8877 EP 8891 DI 10.1021/j100201a036 PG 15 WC Chemistry, Physical SC Chemistry GA JW464 UT WOS:A1992JW46400036 ER PT J AU BEHRENS, R BULUSU, S AF BEHRENS, R BULUSU, S TI THERMAL-DECOMPOSITION OF ENERGETIC MATERIALS .4. DEUTERIUM-ISOTOPE EFFECTS AND ISOTOPIC SCRAMBLING (H/D, C-13/O-18, N-14/N-15) IN CONDENSED-PHASE DECOMPOSITION OF 1,3,5-TRINITROHEXAHYDRO-S-TRIAZINE SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID TANDEM MASS-SPECTROMETRY; OCTAHYDRO-1,3,5,7-TETRANITRO-1,3,5,7-TETRAZOCINE HMX; PYROLYSIS PRODUCTS; 1,3,5,7-TETRANITRO-1,3,5,7-TETRAAZACYCLOOCTANE; RATES; RDX AB The inter- vs intramolecular origin of the products formed in the thermal decomposition of 1,3,5-trinitrohexahydro-s-triazine (RDX) has been traced by isotopic crossover experiments using mixtures of differently labeled analogues of RDX. The isotopic analogues of RDX used in the experiments include H-2, C-13, N-15, and O-18. The fraction of isotopic scrambling and the extent of the deuterium kinetic isotope effect (DKIE) are reported for the different thermal decomposition products. Isotopic scrambling is not observed for the N-N bond in N2O and only in small amounts (7%) in the C-H bonds in CH2O, consistent with a mechanism of their formation through methylene nitramine precursors. A product, oxy-s-triazine (OST, C3H3N3O) does not undergo isotopic scrambling in H/D, N-14/N-15, or C-13/O-18 experiments, and its rate of formation exhibits a DKIE of 1.5. These results are consistent with the formation of OST via unimolecular decomposition of RDX. Another product, 1-nitroso-3,5-dinitrohexahydro-s-triazine (ONDNTA, C3H6N6O5) is found to be formed with complete scrambling of the N-NO bond, suggesting an N-N bond cleavage and a radical recombination process in its formation. One of the hydrogen containing products, H2O, exhibits a DKIE of 1.5 +/- 0.1. In contrast, CH2O and ONDNTA have DKIEs of 1.05 +/- 0.1 and 1.05 +/- 0.2, respectively, indicating that hydrogen transfer is not involved in the rate-limiting step of the reaction pathway leading to the formation of these products. C1 USA,ARMAMENT RES,DEV CTR & ENGN,DIV ENERGET MAT,DOVER,NJ 07801. RP BEHRENS, R (reprint author), SANDIA NATL LABS,COMBUST RES FACIL,LIVERMORE,CA 94551, USA. NR 28 TC 60 Z9 60 U1 4 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 OCT 29 PY 1992 VL 96 IS 22 BP 8891 EP 8897 DI 10.1021/j100201a037 PG 7 WC Chemistry, Physical SC Chemistry GA JW464 UT WOS:A1992JW46400037 ER PT J AU SCHWARZ, HA AF SCHWARZ, HA TI REACTION OF THE HYDRATED ELECTRON WITH WATER SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID ACTIVATION-ENERGY; AQUEOUS-SOLUTIONS; HIGH-TEMPERATURES; RATE CONSTANTS; FREE-RADICALS; RADIOLYSIS; ENTHALPY; ENTROPY AB The reaction of e-(aq) with water was studied as a function of temperature in hydrogen-saturated water and in deaerated formate solutions. The two systems gave similar results. The rate constant at 25-degrees-C is 1040 s-1, and the activation energy is 7.5 +/- 0.2 kcal/mol. This activation energy and a recent determination of the activation energy for the reverse process give DELTAH-degrees-298 = -1.4 +/- 0.2 kcal/mol for the reaction e-(aq) + H2O(liq) half arrow right over half arrow left H. + OH-, to be compared with an earlier value of -1.1 kcal/mol derived from the equilibrium of e-(aq) with NH4+. The earlier value is believed to be less susceptible to errors. RP SCHWARZ, HA (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 21 TC 54 Z9 54 U1 0 U2 18 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 OCT 29 PY 1992 VL 96 IS 22 BP 8937 EP 8941 DI 10.1021/j100201a044 PG 5 WC Chemistry, Physical SC Chemistry GA JW464 UT WOS:A1992JW46400044 ER PT J AU OBERACKER, VE UMAR, AS WELLS, JC STRAYER, MR BOTTCHER, C AF OBERACKER, VE UMAR, AS WELLS, JC STRAYER, MR BOTTCHER, C TI STUDY OF NUCLEAR DISSIPATION VIA MUON-INDUCED FISSION - A RELATIVISTIC LATTICE CALCULATION SO PHYSICS LETTERS B LA English DT Article AB Excited muonic atoms in the actinide region may induce prompt nuclear fission via inverse internal conversion. We solve the time-dependent Dirac equation for a state describing a muon in the Coulomb field of the fissioning nucleus on a three-dimensional lattice and demonstrate that the muon attachment probability to the light fission fragment decreases with the energy dissipated during fission. C1 VANDERBILT UNIV,DEPT PHYS & ASTRON,NASHVILLE,TN 37235. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. RP OBERACKER, VE (reprint author), OAK RIDGE NATL LAB,CTR COMPUTAT INTENS PHYS,OAK RIDGE,TN 37831, USA. RI Umar, Ahmet/J-4125-2013; Wells, Jack/D-3675-2016 OI Umar, Ahmet/0000-0002-9267-5253; Wells, Jack/0000-0002-5083-3030 NR 12 TC 9 Z9 9 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD OCT 29 PY 1992 VL 293 IS 3-4 BP 270 EP 274 DI 10.1016/0370-2693(92)90882-5 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JV679 UT WOS:A1992JV67900003 ER PT J AU BRENNER, DS CASTEN, RF CHOU, WT ZHANG, JY HEYDE, K ZAMFIR, NV AF BRENNER, DS CASTEN, RF CHOU, WT ZHANG, JY HEYDE, K ZAMFIR, NV TI LINEARITY OF NUCLEAR-LEVEL ENERGIES WITH THE P-FACTOR SO PHYSICS LETTERS B LA English DT Article ID INTRUDER STATES; HEAVY-NUCLEI; MASS AB It is shown that isotopic sequences of 2(1)+ level energies, for elements from Zr to the actinides, are linear against the factor P=N(p)N(n)/(N(p)+N(n)). This linearity is interpreted in terms of a simple two-level model. The P-factor also provides a linearization scheme for intruder 0+ energies in the Pb region. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV COLOGNE,INST KERNPHYS,W-5000 COLOGNE,GERMANY. INST MODERN PHYS,LANZHOU,PEOPLES R CHINA. UNIV TENNESSEE,KNOXVILLE,TN 37996. INST NUCL PHYS,GENT,BELGIUM. INST ATOM PHYS,BUCHAREST,ROMANIA. INST THEORET PHYS,GENT,BELGIUM. RP BRENNER, DS (reprint author), CLARK UNIV,WORCESTER,MA 01610, USA. RI Zamfir, Nicolae Victor/F-2544-2011 NR 10 TC 12 Z9 12 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 OCT 29 PY 1992 VL 293 IS 3-4 BP 282 EP 286 DI 10.1016/0370-2693(92)90884-7 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JV679 UT WOS:A1992JV67900005 ER PT J AU GAILLARD, MK AF GAILLARD, MK TI INTERPRETATION OF PRECISION-MEASUREMENTS IN THE STRONGLY INTERACTING LIMIT OF THE STANDARD ELECTROWEAK MODEL SO PHYSICS LETTERS B LA English DT Article ID LARGE HIGGS MASS; RADIATIVE-CORRECTIONS; SCATTERING; BOSONS AB Strong rescattering corrections to one-loop contributions to the parameters of the standard electroweak model are considered. C1 LAWRENCE BERKELEY LAB,DIV PHYS,BERKELEY,CA 94720. RP GAILLARD, MK (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 20 TC 1 Z9 1 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 OCT 29 PY 1992 VL 293 IS 3-4 BP 410 EP 416 DI 10.1016/0370-2693(92)90905-J PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JV679 UT WOS:A1992JV67900026 ER PT J AU BERERA, A AF BERERA, A TI THE PROTON SPIN CONTENT AT SMALL X SO PHYSICS LETTERS B LA English DT Article AB The polarized parton distribution functions are examined at small values of x and exact scaling relations are derived. In contrast to the unpolarized case, the evolution equations are no longer dominated by the gluon contribution. Experimental confirmation of the scaling forms is discussed. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV PHYS,THEORET PHYS GRP,BERKELEY,CA 94720. 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 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD OCT 29 PY 1992 VL 293 IS 3-4 BP 445 EP 450 DI 10.1016/0370-2693(92)90910-V PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JV679 UT WOS:A1992JV67900031 ER PT J AU DERRICK, M KRAKAUER, D MAGILL, S MUSGRAVE, B REPOND, J SUGANO, K STANEK, R TALAGA, RL THRON, J ARZARELLO, F AVED, R BARBAGLI, G BARI, G BASILE, M BELLAGAMBA, L BOSCHERINI, D BRUNI, G BRUNI, P ROMEO, GC CASTELLINI, G CHIARINI, M CIFARELLI, L CINDOLO, F CIRALLI, F CONTIN, A DAURIA, S DELPAPA, C FRASCONI, F GIUSTI, P IACOBUCCI, G LAURENTI, G LEVI, G LIN, Q LISOWSKI, B MACCARRONE, G MARGOTTI, A MASSAM, T NANIA, R NEMOZ, C PALMONARI, F SARTORELLI, G TIMELLINI, R GARCIA, YZ ZICHICHI, A BARGENDE, A BARREIRO, F CRITTENDEN, J DABBOUS, H DESCH, K DIEKMANN, B GEERTS, M GEITZ, G GUTJAHR, B HARTMANN, H HARTMANN, J HAUN, D HEINLOTH, K HILGER, E JAKOB, HP KRAMARCZYK, S KUCKES, M MASS, A MENGEL, S MOLLEN, J MUSCH, H PAUL, E SCHATTEVOY, R SCHNEIDER, B SCHNEIDER, JL WEDEMEYER, R CASSIDY, A CUSSANS, DG DYCE, N FAWCETT, HF FOSTER, B GILMORE, R HEATH, GP LANCASTER, M LLEWELLYN, TJ MALOS, J MORGADO, CJS TAPPER, RJ WILSON, SS RAU, RR BERNSTEIN, A CALDWELL, A GIALAS, I PARSONS, JA RITZ, S SCIULLI, F STRAUB, PB WAI, L YANG, S BARILLARI, T SCHIOPPA, M SUSINNO, G BURKOT, W CHWASTOWSKI, J DWURAZNY, A ESKREYS, A NIZIOL, B JAKUBOWSKI, Z PIOTRZKOWSKI, K ZACHARA, M ZAWIEJSKI, L BORZEMSKI, P ESKREYS, K JELEN, K KISIELEWSKA, D KOWALSKI, T KULKA, J RULIKOWSKAZAREBSKA, E SUSZYCKI, L ZAJAC, J KEDZIERSKI, T KOTANSKI, A PRZYBYCIEN, M BAUERDICK, LAT BEHRENS, U BIENLEIN, JK COLDEWEY, C DANNEMANN, A DIERKS, K DORTH, W DREWS, G ERHARD, P FLASINSKI, M FLECK, I FURTJES, A GLASER, R GOTTLICHER, P HAAS, T HAGGE, L HAIN, W HASELL, D HULTSCHIG, H JAHNEN, G JOOS, P KASEMANN, M KLANNER, R KOCH, W KOTZ, U KOWALSKI, H LABS, J LADAGE, A LOHR, B LOWE, M LUKE, D MAINUSCH, J MANCZAK, O MOMAYEZI, M NICKEL, S NOTZ, D PARK, I POSNECKER, KU ROHDE, M ROS, E SCHNEEKLOTH, U SCHROEDER, J SCHULZ, W SELONKE, F TSCHESLOG, E TSURUGAI, T TURKOT, F VOGEL, W WOENIGER, T WOLF, G YOUNGMAN, C GRABOSCH, HJ LEICH, A MEYER, A RETHFELDT, C SCHLENSTEDT, S CASALBUONI, R DECURTIS, S DOMINICI, D FRANCESCATO, A NUTI, M PELFER, P ANZIVINO, G CASACCIA, R LAAKSO, I DEPASQUALE, S QIAN, S VOTANO, L BAMBERGER, A FREIDHOF, A POSER, T SOLDNERREMBOLD, S THEISEN, G TREFZGER, T BROOK, NH BUSSEY, PJ DOYLE, AT FORBES, JR JAMIESON, VA RAINE, C SAXON, DH GLOTH, G HOLM, U KAMMERLOCHER, H KREBS, B NEUMANN, T WICK, K HOFMANN, A KROGER, W KRUGER, J LOHRMANN, E MILEWSKI, J NAKAHATA, M PAVEL, N POELZ, G SALOMON, R SEIDMAN, A SCHOTT, W WIIK, BH ZETSCHE, F BACON, TC BUTTERWORTH, I MARKOU, C MCQUILLAN, D MILLER, DB MOBAYYEN, MM PRINIAS, A VORVOLAKOS, A BIENZ, T KREUTZMANN, H MALLIK, U MCCLIMENT, E ROCO, M WANG, MZ CLOTH, P FILGES, D CHEN, L IMLAY, R KARTIK, S KIM, HJ MCNEIL, RR METCALF, W CASES, G HERVAS, L LABARGA, L DELPESO, J ROLDAN, J TERRON, J DETROCONIZ, JF IKRAIAM, F MAYER, JK SMITH, GR CORRIVEAU, F GILKINSON, DJ HANNA, DS HUNG, LW MITCHELL, JW PATEL, PM SINCLAIR, LE STAIRS, DG ULLMANN, R BASHINDZHAGYAN, GL ERMOLOV, PF GOLUBKOV, YA KUZMIN, VA KUZNETSOV, EN SAVIN, AA VORONIN, AG ZOTOV, NP BENTVELSEN, S DAKE, A ENGELEN, J DEJONG, P DEJONG, S DEKAMPS, M KOOIJMAN, P KRUSE, A VANDERLUGT, H ODELL, V STRAVER, J TENNER, A TIECKE, H UIJTERWAAL, H VERMEULEN, J WIGGERS, L DEWOLF, E VANWOUDENBERG, R YOSHIDA, R BYLSMA, B DURKIN, LS LI, C LING, TY MCLEAN, KW MURRAY, WN PARK, SK ROMANOWSKI, TA SEIDLEIN, R BLAIR, GA BUTTERWORTH, JM BYRNE, A CASHMORE, RJ COOPERSARKAR, AM DEVENISH, RCE GINGRICH, DM HALLAMBAKER, PM HARNEW, N KHATRI, T LONG, KR LUFFMAN, P MCARTHUR, J MORAWITZ, P NASH, J SMITH, SJP ROOCROFT, NC WILSON, FF ABBIENDI, G BRUGNERA, R CARLIN, R DALCORSO, F DEGIORGI, M DOSSELLI, U FANIN, C GASPARINI, F LIMENTANI, S MORANDIN, M POSOCCO, M STANCO, J STROILI, R VOCI, C LIM, JN OH, BY WHITMORE, J BONORI, M CONTINO, U DAGOSTINI, G GUIDA, M IORI, M MARI, S MARINI, G MATTIOLI, M MONALDI, D NIGRO, A HART, JC MCCUBBIN, NA SHAH, TP SHORT, TL BARBERIS, E CARTIGLIA, N HEUSCH, C HUBBARD, B LESLIE, J NG, JST OSHAUGHNESSY, K SADROZINSKI, HF SEIDEN, A BADURA, E BILTZINGER, J CHAVES, H ROST, M SEIFERT, RJ WALENTA, AH WEIHS, W ZECH, G DAGAN, S HEIFETZ, R LEVY, A ZERZION, D HASEGAWA, T HAZUMI, M ISHII, T KASAI, S KUZE, M NAGASAWA, Y NAKAO, M OKUNO, H TOKUSHUKU, K WATANABE, T YAMADA, S CHIBA, M HAMATSU, R HIROSE, T KITAMURA, S NAGAYAMA, S NAKAMITSU, Y ARNEODO, M COSTA, M FERRERO, MI LAMBERTI, L MASELLI, S PERONI, C SOLANO, A STAIANO, A DARDO, M BAILEY, DC BANDYOPADHYAY, D BENARD, F BHADRA, S BRKIC, M BUROW, BD CHLEBANA, FS CROMBIE, MB HARTNER, GF LEVMAN, GM MARTIN, JF ORR, RS PRENTICE, JD SAMPSON, CR STAIRS, GG TEUSCHER, RJ YOON, TS BULLOCK, FW CATTERALL, CD GIDDINGS, JC JONES, TW KHAN, AM LANE, JB MAKKAR, PL SHAW, D SHULMAN, J BLANKENSHIP, K KOCHOCKI, J LU, B MO, LW CHARCHULA, K CIBOROWSKI, J GAJEWSKI, J GRZELAK, G KASPRZAK, M KRZYZANOWSKI, M MUCHOROWSKI, K NOWAK, RJ PAWLAK, JM STOJDA, K STOPCZYNSKI, A SZWED, R TYMIENIECKA, T WALCZAK, R WROBLEWSKI, AK ZAKRZEWSKI, JA ZARNECKI, AF ADAMUS, M ABRAMOWICZ, H EISENBERG, Y GLASMAN, C KARSHON, U MONTAG, A REVEL, D RONAT, EE SHAPIRA, A ALI, I BEHRENS, B CAMERINI, U DASU, S FORDHAM, C FOUDAS, C GOUSSIOU, A LOMPERSKI, M LOVELESS, RJ NYLANDER, P PTACEK, M REEDER, DD SMITH, WH SILVERSTEIN, S FRISKEN, WR FURUTANI, KM IGA, Y AF DERRICK, M KRAKAUER, D MAGILL, S MUSGRAVE, B REPOND, J SUGANO, K STANEK, R TALAGA, RL THRON, J ARZARELLO, F AVED, R BARBAGLI, G BARI, G BASILE, M BELLAGAMBA, L BOSCHERINI, D BRUNI, G BRUNI, P ROMEO, GC CASTELLINI, G CHIARINI, M CIFARELLI, L CINDOLO, F CIRALLI, F CONTIN, A DAURIA, S DELPAPA, C FRASCONI, F GIUSTI, P IACOBUCCI, G LAURENTI, G LEVI, G LIN, Q LISOWSKI, B MACCARRONE, G MARGOTTI, A MASSAM, T NANIA, R NEMOZ, C PALMONARI, F SARTORELLI, G TIMELLINI, R GARCIA, YZ ZICHICHI, A BARGENDE, A BARREIRO, F CRITTENDEN, J DABBOUS, H DESCH, K DIEKMANN, B GEERTS, M GEITZ, G GUTJAHR, B HARTMANN, H HARTMANN, J HAUN, D HEINLOTH, K HILGER, E JAKOB, HP KRAMARCZYK, S KUCKES, M MASS, A MENGEL, S MOLLEN, J MUSCH, H PAUL, E SCHATTEVOY, R SCHNEIDER, B SCHNEIDER, JL WEDEMEYER, R CASSIDY, A CUSSANS, DG DYCE, N FAWCETT, HF FOSTER, B GILMORE, R HEATH, GP LANCASTER, M LLEWELLYN, TJ MALOS, J MORGADO, CJS TAPPER, RJ WILSON, SS RAU, RR BERNSTEIN, A CALDWELL, A GIALAS, I PARSONS, JA RITZ, S SCIULLI, F STRAUB, PB WAI, L YANG, S BARILLARI, T SCHIOPPA, M SUSINNO, G BURKOT, W CHWASTOWSKI, J DWURAZNY, A ESKREYS, A NIZIOL, B JAKUBOWSKI, Z PIOTRZKOWSKI, K ZACHARA, M ZAWIEJSKI, L BORZEMSKI, P ESKREYS, K JELEN, K KISIELEWSKA, D KOWALSKI, T KULKA, J RULIKOWSKAZAREBSKA, E SUSZYCKI, L ZAJAC, J KEDZIERSKI, T KOTANSKI, A PRZYBYCIEN, M BAUERDICK, LAT BEHRENS, U BIENLEIN, JK COLDEWEY, C DANNEMANN, A DIERKS, K DORTH, W DREWS, G ERHARD, P FLASINSKI, M FLECK, I FURTJES, A GLASER, R GOTTLICHER, P HAAS, T HAGGE, L HAIN, W HASELL, D HULTSCHIG, H JAHNEN, G JOOS, P KASEMANN, M KLANNER, R KOCH, W KOTZ, U KOWALSKI, H LABS, J LADAGE, A LOHR, B LOWE, M LUKE, D MAINUSCH, J MANCZAK, O MOMAYEZI, M NICKEL, S NOTZ, D PARK, I POSNECKER, KU ROHDE, M ROS, E SCHNEEKLOTH, U SCHROEDER, J SCHULZ, W SELONKE, F TSCHESLOG, E TSURUGAI, T TURKOT, F VOGEL, W WOENIGER, T WOLF, G YOUNGMAN, C GRABOSCH, HJ LEICH, A MEYER, A RETHFELDT, C SCHLENSTEDT, S CASALBUONI, R DECURTIS, S DOMINICI, D FRANCESCATO, A NUTI, M PELFER, P ANZIVINO, G CASACCIA, R LAAKSO, I DEPASQUALE, S QIAN, S VOTANO, L BAMBERGER, A FREIDHOF, A POSER, T SOLDNERREMBOLD, S THEISEN, G TREFZGER, T BROOK, NH BUSSEY, PJ DOYLE, AT FORBES, JR JAMIESON, VA RAINE, C SAXON, DH GLOTH, G HOLM, U KAMMERLOCHER, H KREBS, B NEUMANN, T WICK, K HOFMANN, A KROGER, W KRUGER, J LOHRMANN, E MILEWSKI, J NAKAHATA, M PAVEL, N POELZ, G SALOMON, R SEIDMAN, A SCHOTT, W WIIK, BH ZETSCHE, F BACON, TC BUTTERWORTH, I MARKOU, C MCQUILLAN, D MILLER, DB MOBAYYEN, MM PRINIAS, A VORVOLAKOS, A BIENZ, T KREUTZMANN, H MALLIK, U MCCLIMENT, E ROCO, M WANG, MZ CLOTH, P FILGES, D CHEN, L IMLAY, R KARTIK, S KIM, HJ MCNEIL, RR METCALF, W CASES, G HERVAS, L LABARGA, L DELPESO, J ROLDAN, J TERRON, J DETROCONIZ, JF IKRAIAM, F MAYER, JK SMITH, GR CORRIVEAU, F GILKINSON, DJ HANNA, DS HUNG, LW MITCHELL, JW PATEL, PM SINCLAIR, LE STAIRS, DG ULLMANN, R BASHINDZHAGYAN, GL ERMOLOV, PF GOLUBKOV, YA KUZMIN, VA KUZNETSOV, EN SAVIN, AA VORONIN, AG ZOTOV, NP BENTVELSEN, S DAKE, A ENGELEN, J DEJONG, P DEJONG, S DEKAMPS, M KOOIJMAN, P KRUSE, A VANDERLUGT, H ODELL, V STRAVER, J TENNER, A TIECKE, H UIJTERWAAL, H VERMEULEN, J WIGGERS, L DEWOLF, E VANWOUDENBERG, R YOSHIDA, R BYLSMA, B DURKIN, LS LI, C LING, TY MCLEAN, KW MURRAY, WN PARK, SK ROMANOWSKI, TA SEIDLEIN, R BLAIR, GA BUTTERWORTH, JM BYRNE, A CASHMORE, RJ COOPERSARKAR, AM DEVENISH, RCE GINGRICH, DM HALLAMBAKER, PM HARNEW, N KHATRI, T LONG, KR LUFFMAN, P MCARTHUR, J MORAWITZ, P NASH, J SMITH, SJP ROOCROFT, NC WILSON, FF ABBIENDI, G BRUGNERA, R CARLIN, R DALCORSO, F DEGIORGI, M DOSSELLI, U FANIN, C GASPARINI, F LIMENTANI, S MORANDIN, M POSOCCO, M STANCO, J STROILI, R VOCI, C LIM, JN OH, BY WHITMORE, J BONORI, M CONTINO, U DAGOSTINI, G GUIDA, M IORI, M MARI, S MARINI, G MATTIOLI, M MONALDI, D NIGRO, A HART, JC MCCUBBIN, NA SHAH, TP SHORT, TL BARBERIS, E CARTIGLIA, N HEUSCH, C HUBBARD, B LESLIE, J NG, JST OSHAUGHNESSY, K SADROZINSKI, HF SEIDEN, A BADURA, E BILTZINGER, J CHAVES, H ROST, M SEIFERT, RJ WALENTA, AH WEIHS, W ZECH, G DAGAN, S HEIFETZ, R LEVY, A ZERZION, D HASEGAWA, T HAZUMI, M ISHII, T KASAI, S KUZE, M NAGASAWA, Y NAKAO, M OKUNO, H TOKUSHUKU, K WATANABE, T YAMADA, S CHIBA, M HAMATSU, R HIROSE, T KITAMURA, S NAGAYAMA, S NAKAMITSU, Y ARNEODO, M COSTA, M FERRERO, MI LAMBERTI, L MASELLI, S PERONI, C SOLANO, A STAIANO, A DARDO, M BAILEY, DC BANDYOPADHYAY, D BENARD, F BHADRA, S BRKIC, M BUROW, BD CHLEBANA, FS CROMBIE, MB HARTNER, GF LEVMAN, GM MARTIN, JF ORR, RS PRENTICE, JD SAMPSON, CR STAIRS, GG TEUSCHER, RJ YOON, TS BULLOCK, FW CATTERALL, CD GIDDINGS, JC JONES, TW KHAN, AM LANE, JB MAKKAR, PL SHAW, D SHULMAN, J BLANKENSHIP, K KOCHOCKI, J LU, B MO, LW CHARCHULA, K CIBOROWSKI, J GAJEWSKI, J GRZELAK, G KASPRZAK, M KRZYZANOWSKI, M MUCHOROWSKI, K NOWAK, RJ PAWLAK, JM STOJDA, K STOPCZYNSKI, A SZWED, R TYMIENIECKA, T WALCZAK, R WROBLEWSKI, AK ZAKRZEWSKI, JA ZARNECKI, AF ADAMUS, M ABRAMOWICZ, H EISENBERG, Y GLASMAN, C KARSHON, U MONTAG, A REVEL, D RONAT, EE SHAPIRA, A ALI, I BEHRENS, B CAMERINI, U DASU, S FORDHAM, C FOUDAS, C GOUSSIOU, A LOMPERSKI, M LOVELESS, RJ NYLANDER, P PTACEK, M REEDER, DD SMITH, WH SILVERSTEIN, S FRISKEN, WR FURUTANI, KM IGA, Y TI A MEASUREMENT OF IOTA-TOT(GAMMA-P) AT ROOT-S=210GEV SO PHYSICS LETTERS B LA English DT Article ID CENTRAL TRACKING DETECTOR; PARTON DISTRIBUTIONS; CROSS-SECTION; PHOTON; ZEUS; PHOTOPRODUCTION; PARAMETRIZATION; CONSTRUCTION; CALORIMETER; DIFFRACTION C1 IST NAZL FIS NUCL,BOLOGNA,ITALY. UNIV BOLOGNA,I-40126 BOLOGNA,ITALY. UNIV BONN,INST PHYS,W-5300 BONN,GERMANY. UNIV BRISTOL,BRISTOL BS8 1TH,AVON,ENGLAND. BROOKHAVEN NATL LAB,UPTON,NY 11973. COLUMBIA UNIV,NEVIS LABS,IRVINGTON ON HUDSON,NY. IST NAZL FIS NUCL,COSENZA,ITALY. UNIV CALABRIA,DEPT PHYS,COSENZA,ITALY. INST NUCL PHYS,PL-31342 KRAKOW,POLAND. NATL ACAD MED BUENOS AIRES,INST PHYS & NUCL TECHN,RA-1450 BUENOS AIRES,DF,ARGENTINA. JAGIELLONIAN UNIV,DEPT PHYS,PL-31007 KRAKOW,POLAND. DESY,W-2000 HAMBURG 52,GERMANY. DESY ZEUTHEN,INST HOCHENERGIEPHYS,ZEUTHEN,GERMANY. UNIV FLORENCE,I-50121 FLORENCE,ITALY. IST NAZL FIS NUCL,FLORENCE,ITALY. IST NAZL FIS NUCL,LAB NAZL FRASCATI,FRASCATI,ITALY. UNIV FREIBURG,INST PHYS,W-7800 FREIBURG,GERMANY. UNIV GLASGOW,DEPT PHYS & ASTRON,GLASGOW G12 8QQ,SCOTLAND. UNIV HAMBURG,INST EXPTL PHYS 1,W-2000 HAMBURG 13,GERMANY. UNIV HAMBURG,INST EXPTL PHYS 2,W-2000 HAMBURG 13,GERMANY. UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED,HIGH ENERGY NUCL PHYS GRP,LONDON SW7 2AZ,ENGLAND. UNIV IOWA,DEPT PHYS & ASTRON,IOWA CITY,IA 52242. FORSCHUNGSZENTRUM JULICH,INST KERNPHYS,JULICH,GERMANY. LOUISIANA STATE UNIV,DEPT PHYS & ASTRON,BATON ROUGE,LA 70803. UNIV AUTONOMA MADRID,DEPT FIS TEOR,MADRID 34,SPAIN. UNIV MANITOBA,DEPT PHYS,WINNIPEG R3T 2N2,MANITOBA,CANADA. MCGILL UNIV,DEPT PHYS,MONTREAL H3A 2T5,QUEBEC,CANADA. MV LOMONOSOV STATE UNIV,INST NUCL PHYS,MOSCOW 117234,USSR. NIKHEF,AMSTERDAM,NETHERLANDS. OHIO STATE UNIV,DEPT PHYS,COLUMBUS,OH 43210. UNIV OXFORD,DEPT PHYS,OXFORD,ENGLAND. UNIV PADUA,DIPARTIMENTO FIS,I-35100 PADUA,ITALY. IST NAZL FIS NUCL,PADUA,ITALY. PENN STATE UNIV,DEPT PHYS,UNIV PK,PA 16802. UNIV ROME LA SAPIENZA,DIPARTIMENTO FIS,I-00185 ROME,ITALY. RUTHERFORD APPLETON LAB,DIDCOT OX11 0QX,OXON,ENGLAND. UNIV CALIF SANTA CRUZ,SANTA CRUZ,CA 95064. UNIV GESAMTHSCH SIEGEN,FACHBEREICH PHYS,W-5900 SIEGEN 21,GERMANY. TEL AVIV UNIV,SCH PHYS,IL-69978 TEL AVIV,ISRAEL. UNIV TOKYO,INST NUCL STUDY,TOKYO 113,JAPAN. TOKYO METROPOLITAN UNIV,DEPT PHYS,TOKYO 158,JAPAN. UNIV TURIN,DIPARTIMENTO FIS SPERIMENTALE,I-10124 TURIN,ITALY. IST NAZL FIS NUCL,TURIN,ITALY. UNIV TORINO,FAC SCI MFN,ALESSANDRIA,ITALY. UNIV TORONTO,DEPT PHYS,TORONTO M5S 1A1,ONTARIO,CANADA. UNIV LONDON UNIV COLL,DEPT PHYS & ASTRON,LONDON WC1E 6BT,ENGLAND. VIRGINIA POLYTECH INST & STATE UNIV,DEPT PHYS,BLACKSBURG,VA 24061. UNIV WARSAW,INST EXPTL PHYS,PL-00325 WARSAW,POLAND. INST NUCL STUDIES,WARSAW,POLAND. WEIZMANN INST SCI,DEPT NUCL PHYS,IL-76100 REHOVOT,ISRAEL. UNIV WISCONSIN,DEPT PHYS,MADISON,WI 53706. YORK UNIV,DEPT PHYS,N YORK,ONTARIO,CANADA. RP DERRICK, M (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. RI Wiggers, Leo/B-5218-2015; Morandin, Mauro/A-3308-2016; Frasconi, Franco/K-1068-2016; Weihs, Wolfgang/E-8005-2017; De Pasquale, Salvatore/B-9165-2008; Lancaster, Mark/C-1693-2008; Doyle, Anthony/C-5889-2009; Golubkov, Yury/E-1643-2012 OI Wiggers, Leo/0000-0003-1060-0520; Morandin, Mauro/0000-0003-4708-4240; Frasconi, Franco/0000-0003-4204-6587; Weihs, Wolfgang/0000-0003-0884-0947; Brook, Nicholas/0000-0002-1818-0113; De Pasquale, Salvatore/0000-0001-9236-0748; Doyle, Anthony/0000-0001-6322-6195; NR 33 TC 223 Z9 223 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 OCT 29 PY 1992 VL 293 IS 3-4 BP 465 EP 477 DI 10.1016/0370-2693(92)90914-P PG 13 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JV679 UT WOS:A1992JV67900035 ER PT J AU SZALDA, DJ CHOU, MH FUJITA, E CREUTZ, C AF SZALDA, DJ CHOU, MH FUJITA, E CREUTZ, C TI PROPERTIES AND REACTIVITY OF METALLOCARBOXYLATES - CRYSTAL AND MOLECULAR-STRUCTURE OF THE -CO2(2-)-BRIDGED POLYMER ([COIII(EN)2(CO2)](CLO4).H2O)N SO INORGANIC CHEMISTRY LA English DT Note ID CARBON-DIOXIDE; ACTIVATION; OXALATE; CO2 RP SZALDA, DJ (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. RI Fujita, Etsuko/D-8814-2013 NR 10 TC 20 Z9 20 U1 0 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 OCT 28 PY 1992 VL 31 IS 22 BP 4712 EP 4714 DI 10.1021/ic00048a050 PG 3 WC Chemistry, Inorganic & Nuclear SC Chemistry GA JV836 UT WOS:A1992JV83600050 ER PT J AU BERRYMAN, JG MILTON, GW AF BERRYMAN, JG MILTON, GW TI EXACT RESULTS IN LINEAR THERMOMECHANICS OF FLUID-SATURATED POROUS-MEDIA SO APPLIED PHYSICS LETTERS LA English DT Article ID THERMAL-EXPANSION; ROCK AB Exact results are derived relating the various bulk moduli (frame, unjacketed, and pore) and heat capacity of inhomogeneous fluid-saturated porous media to the pertinent thermal expansion coefficients and component moduli when only two porous solid constituents are present. The porous solids need not be space filling or in perfect welded contact, so these results apply to materials containing some voids or cracks interspersed between the two constituents in addition to the interior voids associated with their pores. The key ratio of fluid pressure to temperature change producing uniform expansion or contraction is shown to be independent of porosity. C1 NYU, COURANT INST MATH SCI, NEW YORK, NY 10012 USA. RP LAWRENCE LIVERMORE NATL LAB, POB 808, L-202, LIVERMORE, CA 94551 USA. RI Berryman, James/A-9712-2008 NR 14 TC 9 Z9 9 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 26 PY 1992 VL 61 IS 17 BP 2030 EP 2032 DI 10.1063/1.108349 PG 3 WC Physics, Applied SC Physics GA JV041 UT WOS:A1992JV04100011 ER PT J AU ADELMAN, D BURMESTER, CP WILLE, LT STERNE, PA GRONSKY, R AF ADELMAN, D BURMESTER, CP WILLE, LT STERNE, PA GRONSKY, R TI LONG-RANGE INTERACTIONS, LONG-RANGE ORDER AND A DEVILS STAIRCASE IN YBA2CU3OZ SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter ID SUPERCONDUCTING TRANSITION-TEMPERATURE; PHASE-DIAGRAM; OXYGEN; DIFFRACTION; SUPERSTRUCTURE; STATES AB It is shown that the oxygen-ordered superstructures observed experimentally in YBa2Cu3Oz can be understood in terms of an Ising Hamiltonian containing screened Coulomb repulsions between any two oxygen sites, augmented with a short-range attractive covalent interaction between oxygen sites adjoined by a copper atom. Spatially modulated commensurate phases separated by smooth soliton-like domain walls are obtained through Monte Carlo simulations. These simulations indicate the existence of a complete devil's staircase of phases. It is predicted that the plateau fine structure of the T(c)-z curve and the bond valence sum also exhibit experimentally observable staircase behaviour. C1 FLORIDA ATLANTIC UNIV, DEPT PHYS, BOCA RATON, FL 33431 USA. UNIV CALIF BERKELEY, DEPT MAT SCI & MINERAL ENGN, BERKELEY, CA 94720 USA. LAWRENCE BERKELEY LAB, DIV MAT SCI, BERKELEY, CA 94720 USA. LAWRENCE LIVERMORE NATL LAB, DEPT CHEM & MAT SCI, LIVERMORE, CA 94550 USA. NR 36 TC 17 Z9 17 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 EI 1361-648X J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD OCT 26 PY 1992 VL 4 IS 43 BP L585 EP L592 DI 10.1088/0953-8984/4/43/003 PG 8 WC Physics, Condensed Matter SC Physics GA JW045 UT WOS:A1992JW04500003 ER PT J AU CHENG, JL JIN, YM WUNDERLICH, B CHENG, SZD YANDRASITS, MA ZHANG, AQ PERCEC, V AF CHENG, JL JIN, YM WUNDERLICH, B CHENG, SZD YANDRASITS, MA ZHANG, AQ PERCEC, V TI SOLID-STATE C-13 NMR-STUDIES OF MOLECULAR-MOTION IN MBPE-9 AND MBPE-5 SO MACROMOLECULES LA English DT Article ID NUCLEAR MAGNETIC-RESONANCE; LIQUID-CRYSTAL POLYMERS; CONFORMATIONAL ISOMERISM; MESOPHASE TRANSITIONS; MAIN-CHAIN; THERMOTROPIC COPOLYESTERS; POLYMETHYLENE SPACERS; PHASE-TRANSITIONS; POLYETHERS; UNITS AB The molecular motion in the polymers poly[oxy(3-methyl-1,4-phenylene)ethylene-1,4-phenyleneoxynonamethylene], MBPE-9, and poly[oxy(3-methylene-1,4-phenylene)ethylene-1,4-phenyleneoxypentamethylene], MBPE-5, was studied at various temperatures on cooling with solid-state C-13 NMR. The techniques used were (1) cross-polarization and magic-angle spinning (CP-MAS), (2) dipolar dephasing, and (3) conventional one-pulse NMR with two-level broad-band proton decoupling (BILEV) under MAS conditions. The observed changes in chemical shift are interpreted in terms of the gamma-gauche effect. The mobility in the flexible spacer in MBPE-9 decreases on cooling from the melt at a mesophase transition (345.6 K at 10 K/min), which indicates that ordering in this spacer is the driving force in this transition, while the phenylene groups remain mobile. A second transition at 331.0 K is linked with the phenylene groups becoming restricted in their motion. Both states reached on cooling from the melt are conformationally disordered (condis phase). The similarity of the high-temperature phase with a liquid crystalline phase is discussed. In MBPE-5 the cooling rate in the NMR experiments is limited and only the low -temperature condis phase could be identified. C1 UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831. UNIV AKRON,COLL POLYMER SCI & POLYMER ENGN,INST POLYMER SCI,AKRON,OH 44325. UNIV AKRON,COLL POLYMER SCI & POLYMER ENGN,DEPT POLYMER SCI,AKRON,OH 44325. CASE WESTERN RESERVE UNIV,DEPT MACROMOLEC SCI,CLEVELAND,OH 44106. RI Percec, Virgil/H-6316-2014 OI Percec, Virgil/0000-0001-5926-0489 NR 49 TC 33 Z9 34 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 26 PY 1992 VL 25 IS 22 BP 5991 EP 5999 DI 10.1021/ma00048a021 PG 9 WC Polymer Science SC Polymer Science GA JV821 UT WOS:A1992JV82100021 ER PT J AU GILLIOM, LR HONNELL, KG AF GILLIOM, LR HONNELL, KG TI OBSERVATION OF A REACTION FRONT IN THE BULK CATALYTIC-HYDROGENATION OF A POLYOLEFIN SO MACROMOLECULES LA English DT Note ID POLYMERS RP GILLIOM, LR (reprint author), SANDIA NATL LABS,DEPT ORGAN & ELECTR MAT,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 11 TC 11 Z9 11 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 26 PY 1992 VL 25 IS 22 BP 6066 EP 6068 DI 10.1021/ma00048a034 PG 3 WC Polymer Science SC Polymer Science GA JV821 UT WOS:A1992JV82100034 ER PT J AU GINSPARG, P QUEVEDO, F AF GINSPARG, P QUEVEDO, F TI STRINGS ON CURVED SPACE-TIMES - BLACK-HOLES, TORSION, AND DUALITY SO NUCLEAR PHYSICS B LA English DT Article ID SOLUBLE SUPERCONFORMAL THEORY; CALABI-YAU MANIFOLDS; SUPERSTRING VACUA; SIGMA-MODELS; DIMENSIONS; SYMMETRIES; PAIR AB We present a general discussion of strings propagating on noncompact coset spaces G/H in terms of gauged WZW models, emphasizing the role played by isometries in the existence of target-space duality. Fixed points of the gauged transformations induce metric singularities and, in the case of abelian subgroups H, become horizons in a dual geometry. We also give a classification of models with a single timelike coordinate together with an explicit list for dimensions D less-than-or-equal-to 10. We study in detail the class of models described by the cosets SL(2, R) x SO(1, 1)D-2/SO(1, 1). For D greater-than-or-equal-to 2 each coset represents two different space-time geometries: (2d black hole) x R(D-2) and (3d black string) x R(D-3) with nonvanishing torsion. They are shown to be dual in such a way that the singularity of the former geometry (which is not due to a fixed point) is mapped to a regular surface (i.e. not even a horizon) in the latter. These cosets also lead to the conformal field theory description of known and new cosmological string models. RP GINSPARG, P (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,MS-B285,LOS ALAMOS,NM 87544, USA. NR 54 TC 76 Z9 76 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 OCT 26 PY 1992 VL 385 IS 3 BP 527 EP 557 DI 10.1016/0550-3213(92)90057-I PG 31 WC Physics, Particles & Fields SC Physics GA JZ428 UT WOS:A1992JZ42800005 ER PT J AU HERCZEG, P MOHAPATRA, RN AF HERCZEG, P MOHAPATRA, RN TI MUONIUM TO ANTIMUONIUM CONVERSION AND THE DECAY MU+-]E(+)(NU)OVER-BAR-(E)NU(MU) IN LEFT-RIGHT SYMMETRICAL MODELS SO PHYSICAL REVIEW LETTERS LA English DT Article ID NEUTRINO MASSES; LEPTON-NUMBER; SPONTANEOUS VIOLATION; HEAVY NEUTRINOS; PARITY; BOUNDS; LIMITS; CONSERVATION; CONSTRAINTS; COSMOLOGY AB We show that in the minimal left-right symmetric model with triplet Higgs bosons the range of the muon neutrino mass for which nu(mu) is required by cosmological considerations to be unstable can be probed by muonium to antimuonium conversion (M --> MBAR) and/or by the exotic muon decay mu+ --> e+nu(e)nu(mu)BAR. We point out that if all the leptonic mixing matrices are hierarchical and the Dirac masses of the neutrinos are equal to the masses of the corresponding charged leptons, there is a lower bound in this range for the rates of both of these processes. We find \G(MMBAR)\ greater than or similar to 7 x 10(-5)G(F) and \G(mu)(e)\greater than or similar to 2 x 10(-4) G(F) for the strength of the M --> MBAR and mu+ --> e+nu(e)nu(mu)BAR interactions. C1 UNIV MARYLAND,DEPT PHYS & ASTRON,COLL PK,MD 20742. RP HERCZEG, P (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 52 TC 57 Z9 57 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 OCT 26 PY 1992 VL 69 IS 17 BP 2475 EP 2478 DI 10.1103/PhysRevLett.69.2475 PG 4 WC Physics, Multidisciplinary SC Physics GA JV013 UT WOS:A1992JV01300006 ER PT J AU LAURITSEN, T BENET, P KHOO, TL BEARD, KB AHMAD, I CARPENTER, MP DALY, PJ DRIGERT, MW GARG, U FERNANDEZ, PB JANSSENS, RVF MOORE, EF WOLFS, FLH YE, D AF LAURITSEN, T BENET, P KHOO, TL BEARD, KB AHMAD, I CARPENTER, MP DALY, PJ DRIGERT, MW GARG, U FERNANDEZ, PB JANSSENS, RVF MOORE, EF WOLFS, FLH YE, D TI FEEDING OF SUPERDEFORMED BANDS - THE MECHANISM AND CONSTRAINTS ON BAND ENERGIES AND THE WELL DEPTH SO PHYSICAL REVIEW LETTERS LA English DT Article ID NUCLEI AB Energy distributions leading to normal and superdeformed (SD) states in 192Hg have been measured A model, based on Monte Carlo simulations of gamma cascades, successfully reproduces the entry distribution for SD states, as well as all other known observables connected with the population of SD states. Comparison of experimental and model results, together with the measured SD entry distribution, suggest that the SD band lies 3.3-4.3 MeV above the normal yrast line when it decays around spin 10 and the SD well depth is 3.5-4.5 MeV at spin 40. C1 PURDUE UNIV,W LAFAYETTE,IN 47907. UNIV NOTRE DAME,NOTRE DAME,IN 46556. EG&G IDAHO INC,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415. RP LAURITSEN, T (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. RI Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 23 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 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 26 PY 1992 VL 69 IS 17 BP 2479 EP 2482 DI 10.1103/PhysRevLett.69.2479 PG 4 WC Physics, Multidisciplinary SC Physics GA JV013 UT WOS:A1992JV01300007 ER PT J AU MORAN, MJ AF MORAN, MJ TI X-RAY GENERATION BY THE SMITH-PURCELL EFFECT SO PHYSICAL REVIEW LETTERS LA English DT Article ID FREE-ELECTRON LASERS AB Smith-Purcell (S-P) radiation is produced when electrons graze the surface of a grating. Calculations based on the theory of diffraction radiation show that, given severe restrictions on e--beam quality, S-P radiation is highly efficient. Efficient S-P x-ray generation requires relativistic e- beams having a transverse momentum and dimension whose product approaches the Heisenberg uncertainty limit. RP MORAN, MJ (reprint author), LAWRENCE LIVERMORE NATL LAB, L-41, POB 808, LIVERMORE, CA 94550 USA. NR 22 TC 27 Z9 27 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 26 PY 1992 VL 69 IS 17 BP 2523 EP 2526 DI 10.1103/PhysRevLett.69.2523 PG 4 WC Physics, Multidisciplinary SC Physics GA JV013 UT WOS:A1992JV01300018 ER PT J AU RASOLT, M PERROT, F AF RASOLT, M PERROT, F TI SPONTANEOUSLY SYMMETRY-BROKEN-CURRENT-CARRYING STATES IN A STRONGLY INHOMOGENEOUS INTERACTING 2-DIMENSIONAL FERMI-LIQUID SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIMENSIONAL ELECTRON-GAS; HIGH-TC SUPERCONDUCTORS; HUBBARD-MODEL; GROUND-STATE; TRANSITION AB We examine the nature of the ground state of a two-dimensional interacting electron gas in a self-induced gauge field. We show that for a realistic form of such a many-body gauge field in two dimensions and increasing inhomogeneity of the electron density, a spontaneous current-carrying state develops. Its relation to other time-reversal broken-symmetry ground states is discussed. C1 CEA, F-94190 VILLENEUVE, FRANCE. RP RASOLT, M (reprint author), OAK RIDGE NATL LAB, DIV SOLID STATE, OAK RIDGE, TN 37831 USA. NR 23 TC 23 Z9 23 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 26 PY 1992 VL 69 IS 17 BP 2563 EP 2566 DI 10.1103/PhysRevLett.69.2563 PG 4 WC Physics, Multidisciplinary SC Physics GA JV013 UT WOS:A1992JV01300028 ER PT J AU MA, Y WASSDAHL, N SKYTT, P GUO, J NORDGREN, J JOHNSON, PD RUBENSSON, JE BOSKE, T EBERHARDT, W KEVAN, SD AF MA, Y WASSDAHL, N SKYTT, P GUO, J NORDGREN, J JOHNSON, PD RUBENSSON, JE BOSKE, T EBERHARDT, W KEVAN, SD TI SOFT-X-RAY RESONANT INELASTIC-SCATTERING AT THE CK EDGE OF DIAMOND SO PHYSICAL REVIEW LETTERS LA English DT Article ID MONOCHROMATIZED SYNCHROTRON RADIATION; CORE EXCITON; FLUORESCENCE; EMISSION; SPECTROSCOPY; SPECTRA AB We present carbon K emission spectra of diamond excited with high-resolution undulator radiation. The valence-band emission spectra are shown to be strongly dependent on the excitation energy, up to 20-30 eV above the C K edge. It is proposed that the dependence is indicative of the resonant inelastic scattering description of these emission spectra, i.e., the absorption-emission process should be described as a single scattering event where the momenta of the photoelectron and the valence hole in the final state are related by momentum conservation. C1 PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. UNIV UPPSALA, DEPT PHYS, S-75121 UPPSALA, SWEDEN. FORSCHUNGSZENTRUM JULICH, INST FESTKORPERPHYS, W-5170 JULICH, GERMANY. UNIV OREGON, DEPT PHYS, EUGENE, OR 97403 USA. RP MA, Y (reprint author), BROOKHAVEN NATL LAB, DEPT PHYS, BLDG 725-X1, UPTON, NY 11973 USA. RI Kevan, Stephen/F-6415-2010 OI Kevan, Stephen/0000-0002-4621-9142 NR 24 TC 206 Z9 207 U1 2 U2 27 PU AMER 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 OCT 26 PY 1992 VL 69 IS 17 BP 2598 EP 2601 DI 10.1103/PhysRevLett.69.2598 PG 4 WC Physics, Multidisciplinary SC Physics GA JV013 UT WOS:A1992JV01300037 ER PT J AU STOJIMIROVIC, A KADOTA, K CHUDNOVSKY, A AF STOJIMIROVIC, A KADOTA, K CHUDNOVSKY, A TI AN EQUILIBRIAL PROCESS ZONE IN POLYMERIC MATERIALS SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article ID SLOW CRACK-GROWTH; POLYETHYLENE; INITIATION; FAILURE; STRAIN; NOTCH AB A process zone at the tip of a fatigue crack grown in polymeric materials has been widely reported. A new method that treats the process zone as an allotropically transformed material is employed for the prediction of the process-zone size. A specific energy of material transformation as well as transformation stress and draw ratio are determined from an independent test on polymer drawing. The prediction of the model with no adjustable parameters appears to be in a good agreement with the experimentally observed process zone for various polyethylenes and polycarbonate. C1 UNIV ILLINOIS,DEPT CEMM,POB 4348,CHICAGO,IL 60680. ARGONNE NATL LAB,ARGONNE,IL 60439. NR 13 TC 25 Z9 25 U1 0 U2 1 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 OCT 25 PY 1992 VL 46 IS 6 BP 1051 EP 1056 DI 10.1002/app.1992.070460614 PG 6 WC Polymer Science SC Polymer Science GA JP873 UT WOS:A1992JP87300014 ER PT J AU SCHULTZ, JR GONG, EL MCCALL, MR NICHOLS, AV CLIFT, SM RUBIN, EM AF SCHULTZ, JR GONG, EL MCCALL, MR NICHOLS, AV CLIFT, SM RUBIN, EM TI EXPRESSION OF HUMAN APOLIPOPROTEIN-A-II AND ITS EFFECT ON HIGH-DENSITY-LIPOPROTEINS IN TRANSGENIC MICE SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID CORONARY-ARTERY DISEASE; HEPATIC TRIGLYCERIDE LIPASE; PARTICLE-SIZE DISTRIBUTION; ISCHEMIC HEART-DISEASE; CHOLESTEROL-ACYLTRANSFERASE; STRUCTURAL ORGANIZATION; NUCLEOTIDE-SEQUENCE; GEL-ELECTROPHORESIS; ACID SEQUENCE; MESSENGER-RNA AB Apolipoproteins A-I and A-II comprise approximately 70 and 20%, respectively, of the total protein content of HDL. Evidence suggests that apoA-I plays a central role in determining the structure and plasma concentration of HDL, while the role of apoA-II is uncertain. To help define the function of apoA-II and determine what effect increasing its plasma concentration has on HDL, transgenic mice expressing human apoA-II and both human apoA-I and human apoA-II were produced. Human apoA-II mRNA is expressed exclusively in the livers of transgenic animals, and the protein exists as a dimer as it does in humans. High level expression of human apoA-II did not increase HDL concentrations or decrease plasma concentrations of murine apoA-I and apoA-II in contrast to what was observed in mice overexpressing human apoA-I. The primary effect of overexpressing human apoA-II was the appearance of small HDL particles composed exclusively of human apoA-II. HDL from mice transgenic for both human apoA-I and human apoA-II displayed a unique size distribution when compared with either apoA-I or apoA-II transgenic mice and contain particles with both these human apolipoproteins. These results in mice, indicating that human apoA-II participates in determining HDL size, parallel results from human studies. C1 LAWRENCE BERKELEY LAB,DIV LIFE SCI,1 CYCLOTRON RD,BERKELEY,CA 94720. FU NHLBI NIH HHS [HL18574, R01-HL46281] NR 55 TC 94 Z9 94 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 OCT 25 PY 1992 VL 267 IS 30 BP 21630 EP 21636 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA JV011 UT WOS:A1992JV01100059 PM 1400473 ER PT J AU CAMPBELL, DB STACY, NJS NEWMAN, WI ARVIDSON, RE JONES, EM MUSSER, GS ROPER, AY SCHALLER, C AF CAMPBELL, DB STACY, NJS NEWMAN, WI ARVIDSON, RE JONES, EM MUSSER, GS ROPER, AY SCHALLER, C TI MAGELLAN OBSERVATIONS OF EXTENDED IMPACT CRATER RELATED FEATURES ON THE SURFACE OF VENUS SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID INITIAL ANALYSIS; RADAR AB A total of 57 parabolic-shaped and 9 approximately circular extended, impact crater related features have been found in Magellan synthetic aperture radar (SAR) and thermal emissivity data covering 92% of the surface of Venus. The parabolic features are, with seven exceptions, oriented E-W with the apex to the east and the impact crater located just west of the apex. They were first identified in the surface emissivity data derived from Magellan radiometry measurements, but the great majority are only clearly visible in the SAR imagery. The overall sizes of both the parabolic and circular features range from several hundred to about two thousand kilometers and are loosely correlated with the diameters of the "parent" craters. The floors of almost all these craters have high specific radar backscatter cross sections (i.e., they are bright in the SAR imagery) relative to their surroundings and tend to have low emissivities. Approximately one-third of the impact craters with diameters greater-than-or-equal-to 15 km appear to have bright floors and about half of these have an associated parabolic feature which can be observed in the SAR or emissivity data. No features have been found which overlie the parabolic features, indicating that they are among the youngest features on the surface of the planet. This suggests that radar-bright floors characterize the freshest impact craters and that modification processes subsequently darken their radar signature. A model for the formation of the parabolic features is developed based on the injection of small particles into the upper atmosphere at the time of impact and their transport to the west by the E-W zonal winds. Fitting of a small perturbation scattering model to the measured average scattering law for the parabolic features placed an upper limit of about 0.6 cm on the wavelength scale (12.6 cm) surface roughness and, hence, of 1 to 2 cm on the largest particle sizes of interest. Fallout times from 50 km in the Venus atmosphere for particles of this size are about 2 hours, allowing westerly drifts of several hundred kilometers for zonal winds of 50 to 100 m s-1. Measurements of the change in backscatter cross section of features overlaid by these extended ejecta deposits, are consistent with deposit depths of a few centimeters to 1 or 2 C1 WASHINGTON UNIV,MCDONNELL CTR SPACE SCI,DEPT EARTH & PLANETARY SCI,ST LOUIS,MO 63130. UNIV WISCONSIN,DEPT PHYS & ASTRON,EAU CLAIRE,WI 54702. CORNELL UNIV,DEPT ASTRON,ITHACA,NY 14853. LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87544. LOS ALAMOS NATL LAB,DIV EARTH & ENVIRONM SCI,LOS ALAMOS,NM 87544. UNIV CALIF LOS ANGELES,DEPT EARTH & SPACE SCI,LOS ANGELES,CA 90024. RP CAMPBELL, DB (reprint author), CORNELL UNIV,NATL ASTRON & IONOSPHERE CTR,SPACE SCI BLDG,ITHACA,NY 14853, USA. RI Newman, William/E-5918-2011 OI Newman, William/0000-0002-9835-1428 NR 38 TC 67 Z9 68 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD OCT 25 PY 1992 VL 97 IS E10 BP 16249 EP 16277 PG 29 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA JV615 UT WOS:A1992JV61500015 ER PT J AU BREMER, MCD GIMBLE, FS THORNER, J SMITH, CL AF BREMER, MCD GIMBLE, FS THORNER, J SMITH, CL TI VDE ENDONUCLEASE CLEAVES SACCHAROMYCES-CEREVISIAE GENOMIC DNA AT A SINGLE SITE - PHYSICAL MAPPING OF THE VMA1 GENE SO NUCLEIC ACIDS RESEARCH LA English DT Article ID YEAST C1 UNIV CALIF BERKELEY,DEPT MOLEC & CELL BIOL,DIV BIOCHEM & MOLEC BIOL,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV CHEM BIODYNAM,BERKELEY,CA 94720. FU NIGMS NIH HHS [GM21841] NR 9 TC 34 Z9 34 U1 0 U2 0 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD OCT 25 PY 1992 VL 20 IS 20 BP 5484 EP 5484 DI 10.1093/nar/20.20.5484 PG 1 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA JW666 UT WOS:A1992JW66600039 PM 1437572 ER PT J AU HENDERSON, CC CAHILL, PA AF HENDERSON, CC CAHILL, PA TI SEMIEMPIRICAL CALCULATIONS OF THE ISOMERIC C60 DIHYDRIDES SO CHEMICAL PHYSICS LETTERS LA English DT Article ID BUCKMINSTERFULLERENE C60; SEMIEMPIRICAL METHODS; CARBON CLUSTERS; FULLERENES; C-60; C-70; REACTIVITY; CHEMISTRY; IONS; OPTIMIZATION AB The reduction of C60 to C60H2 may result in the formation of 23 distinct, energetically non-equivalent isomers. of which three are meso. The heats of formation of these isomers were calculated at spin-restricted and spin-unrestricted semi-empirical levels using PM3 parameters. Our results indicate that at most two of the 23 isomers are likely to be significantly populated at thermal equilibrium at room temperature. The relative energies of the three lowest-energy isomers at the spin-unrestricted level are 0 kcal/mol for substitution across a 6,6-ring fusion, +2.5 kcal/mol for substitution 1,4 across a 6 ring, and +9.1 kcal/mol for substitution 2,6 across a naphthalene ring subunit. A concise nomenclature for designating substitutional patterns on C60 and fullerenes in general is proposed. RP HENDERSON, CC (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 45 TC 48 Z9 48 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD OCT 23 PY 1992 VL 198 IS 6 BP 570 EP 576 DI 10.1016/0009-2614(92)85032-6 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JU851 UT WOS:A1992JU85100006 ER PT J AU HAMZA, AV BALOOCH, M AF HAMZA, AV BALOOCH, M TI THE ADSORPTION OF C60 AND THE COADSORPTION OF C60 AND H2O ON ALPHA-AL2O3 (1(1)OVER-BAR02)-(2X1) SO CHEMICAL PHYSICS LETTERS LA English DT Article AB Binding of submonolayer coverages of C60 to alpha-Al2O3 (1102BAR)-(2 X 1) is observed by temperature-programmed desorption with peak temperatures for desorption between 430 and 460 K. Estimated first-order activation energy and pre-exponential factor are 25 +/- 6 kcal/mol and 6.3 x 10(11) s-1. Multilayer desorption of C60 behaves similarly to that observed previously from the (0001) surface. Exposure of C60 to a water pre-dosed surface did not displace the adsorbed surface hydroxyls. Concomitant desorption of C60 and water is observed from a water pre-dosed surface subsequently exposed to C60 multilayers, whereas water post-dosed onto a C60-covered surface has a sticking probability less than 4 x 10(-3). RP HAMZA, AV (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,LIVERMORE,CA 94551, USA. NR 12 TC 20 Z9 20 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD OCT 23 PY 1992 VL 198 IS 6 BP 603 EP 608 DI 10.1016/0009-2614(92)85036-A PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA JU851 UT WOS:A1992JU85100010 ER PT J AU VAIRAVAMURTHY, A MOPPER, K TAYLOR, BF AF VAIRAVAMURTHY, A MOPPER, K TAYLOR, BF TI OCCURRENCE OF PARTICLE-BOUND POLYSULFIDES AND SIGNIFICANCE OF THEIR REACTION WITH ORGANIC MATTERS IN MARINE-SEDIMENTS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ORGANOSULFUR COMPOUNDS; FLASH PYROLYSIS; SULFUR; THIOLS; 3-MERCAPTOPROPIONATE; CHROMATOGRAPHY; WATERS AB Inorganic polysulfides (S(n)2-, where n > 1) contribute to the incorporation of sulfur into organic matter in reducing sediments, especially when conditions exist for partial oxidation of sulfide. Inorganic polysulfides have been assumed previously to exist only in the aqueous phase. Our results suggest that a significant fraction of inorganic polysulfides is bound to the particulate-phase of sediments and can react with carbon-carbon unsaturated bonds in organic matter, thereby attaching it to the particulate phase through polysulfide linkages. This mechanism may affect the bioavailability of the reactive organic matter in sediments and hence may play an important role in the preservation of organic matter in anoxic marine sediments. C1 WASHINGTON STATE UNIV,DEPT CHEM,PULLMAN,WA 99164. UNIV MIAMI,DIV MARINE & ATMOSPHER CHEM RSMAS,MIAMI,FL 33149. RP VAIRAVAMURTHY, A (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973, USA. NR 31 TC 34 Z9 34 U1 0 U2 3 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 OCT 23 PY 1992 VL 19 IS 20 BP 2043 EP 2046 DI 10.1029/92GL01995 PG 4 WC Geosciences, Multidisciplinary SC Geology GA JW001 UT WOS:A1992JW00100013 ER PT J AU WARBURTON, EK BROWN, BA MILLENER, DJ AF WARBURTON, EK BROWN, BA MILLENER, DJ TI LARGE-BASIS SHELL-MODEL TREATMENT OF A = 16 SO PHYSICS LETTERS B LA English DT Article ID 1ST-FORBIDDEN BETA-DECAY; LEAD REGION; MESONIC ENHANCEMENT AB A recently constructed shell-model interaction is used to calculate wave functions for the 0+ states of O-16 in a six-shell (0 + 2 + 4)homegaBAR model space. Several different methods of dealing with problems arising from truncation of the model space at 4homegaBAR are described. The preferred is to lower the 4homegaBAR components by the same energy shift as occurs for the ground state when changing from 0homegaBAR to (0 + 2 + 4)homegaBAR. The strong role of the SU3 (20) component of the interaction is described. it is shown that a clear and sensitive test of the wave functions of the ground state and 6049 keV deformed state is the N-16 2- unique first-forbidden decay rates to them. Good agreement is found for these observables. C1 NATL SUPERCOND CYCLOTRON LAB,E LANSING,MI 48824. DEPT PHYS & ASTRON,E LANSING,MI 48824. RP WARBURTON, EK (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 21 TC 54 Z9 54 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 OCT 22 PY 1992 VL 293 IS 1-2 BP 7 EP 12 DI 10.1016/0370-2693(92)91472-L PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JU732 UT WOS:A1992JU73200002 ER PT J AU SCHMIDT, CR AF SCHMIDT, CR TI A TOP QUARK CP-VIOLATING ASYMMETRY IN SUPERSYMMETRIC MODELS SO PHYSICS LETTERS B LA English DT Article ID ELECTRIC-DIPOLE MOMENT; HIGGS-BOSON-EXCHANGE; NEUTRON; DECAYS; SEARCH AB The difference in the transverse energy distribution of leptons and antileptons from ttBAR events at hadron colliders is a potential signal of non-standard-model CP violation. We investigate contributions to the asymmetry that may arise in supersymmetric models. The effect may be as large as a few times 10(-3). RP SCHMIDT, CR (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 32 TC 51 Z9 51 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 OCT 22 PY 1992 VL 293 IS 1-2 BP 111 EP 116 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA JU732 UT WOS:A1992JU73200017 ER PT J AU KUBINEC, MG WEMMER, DE AF KUBINEC, MG WEMMER, DE TI NMR EVIDENCE FOR DNA BOUND WATER IN SOLUTION SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Note ID AQUEOUS-SOLUTION; PROTEIN HYDRATION; MOLECULES; EXCHANGE; DODECAMER C1 LAWRENCE BERKELEY LAB,DIV STRUCT BIOL,BERKELEY,CA 94720. NR 14 TC 129 Z9 129 U1 0 U2 9 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 OCT 21 PY 1992 VL 114 IS 22 BP 8739 EP 8740 DI 10.1021/ja00048a079 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA JV028 UT WOS:A1992JV02800079 ER PT J AU SEGEL, LA PERELSON, AS AF SEGEL, LA PERELSON, AS TI PLASMID COPY NUMBER CONTROL - A CASE-STUDY OF THE QUASI-STEADY-STATE ASSUMPTION SO JOURNAL OF THEORETICAL BIOLOGY LA English DT Article ID PRIMER TRANSCRIPT; RNA-I; DNA-REPLICATION; RIBONUCLEASE-H; COLE1 DNA; BINDING; MUTATIONS; KINETICS; PROTEIN C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP SEGEL, LA (reprint author), WEIZMANN INST SCI,DEPT APPL MATH & COMP SCI,IL-76100 REHOVOT,ISRAEL. NR 23 TC 4 Z9 4 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-5193 J9 J THEOR BIOL JI J. Theor. Biol. PD OCT 21 PY 1992 VL 158 IS 4 BP 481 EP 494 DI 10.1016/S0022-5193(05)80711-8 PG 14 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA JV922 UT WOS:A1992JV92200005 PM 1287367 ER PT J AU SLOOF, GW VISSER, FC TEERLINK, T COMANS, EFI EENIGE, MJ VANDERVUSSE, GJ KNAPP, FF AF SLOOF, GW VISSER, FC TEERLINK, T COMANS, EFI EENIGE, MJ VANDERVUSSE, GJ KNAPP, FF TI INCORPORATION OF RADIOIODINATED FATTY-ACIDS INTO CARDIAC PHOSPHOLIPIDS OF NORMOXIC CANINE MYOCARDIUM SO MOLECULAR AND CELLULAR BIOCHEMISTRY LA English DT Article DE NORMAL CANINE MYOCARDIUM; RADIOIODINATED FATTY ACIDS; PHOSPHOLIPID DISTRIBUTION ID MEMBRANE PHOSPHOLIPIDS; ISCHEMIC MYOCARDIUM; HEPTADECANOIC ACID; ACCUMULATION; METABOLISM; INVITRO; INJURY; HEART; SCINTIGRAPHY; DEPLETION AB The aim of this study was to assess the phospholipid distribution of radioiodinated 17-iodoheptadecanoic acid (IHDA), 15-(p-iodophenyl)pentadecanoic acid (p-IPPA) and 15-(p-iodophenyl)-3,3-dimethylpentadecanoic acid (DMIPPA) under normoxic conditions and to compare these data with the fatty acid composition of the phospholipid classes. After simultaneous i.v. injection of the radioiodinated fatty acids (I-123-IHDA; I-131-p-IPPA; I-125-DMIPPA) in open-chest dogs seven myocardial biopsies were taken over 40 min (n = 26). After lipid extraction of the biopsies the organic phase was analyzed for both neutral and polar lipids by two different TLC systems. The following polar lipid fractions were analyzed: lysophopshatidylcholine (LPC), sphingomyelin (SPH), phosphatidylcholine (PC; lecithin), phosphatidylinositol (PI), phosphatidylserine (PS), phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG; cardiolipin) and neutral lipids. Fractions were counted in a gamma well counter and corrected for cross-over and recovery. Results of the polar phospholipids analysis showed that IHDA has the highest incorporation into the phospholipids. The IHDA was mainly incorporated into PI (45.6%) followed by PC (30.9%), PE (14.0%) and PS (5.6%). The p-IPPA was predominantly incorporated incorporated into PC (37.2%), followed by PS (20.1%) and PE (13.7%). In contrast to IHDA, incorporation of p-IPPA into PI was small (6.4%). The DMIPPA analogue was incorporated into phopsholipids to only a very small degree, compared to IHDA and p-IPPA. PS (27.4%) was the only considerable phospholipid fraction into which DMIPPA was incorporated. The results clearly demonstrated that these radioiodinated fatty acid analogues have entirely different patterns of phospholipid incorporation.Major resemblances have been found between the incorporation into phospholipids of IHDA and the phospholipid distribution of the natural counterpart: stearic acid. The p-IPPA phospholipid incorporation only partly resembles the phospholipid distribution of palmitic acid. DMIPPA is because of its modified structure, incorporated into phospholipids to a low extent, mainly into PS. C1 UNIV LIMBURG,DEPT PHYSIOL,6200 MD MAASTRICHT,NETHERLANDS. OAK RIDGE NATL LAB,NUCL MED GRP,OAK RIDGE,TN. RP SLOOF, GW (reprint author), FREE UNIV AMSTERDAM HOSP,DEPT CARDIOL,METABOL LAB,DE BOELELAAN 1117,1007 MB AMSTERDAM,NETHERLANDS. NR 33 TC 6 Z9 6 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0300-8177 J9 MOL CELL BIOCHEM JI Mol. Cell. Biochem. PD OCT 21 PY 1992 VL 116 IS 1-2 BP 79 EP 87 DI 10.1007/BF01270573 PG 9 WC Cell Biology SC Cell Biology GA JZ206 UT WOS:A1992JZ20600013 PM 1480157 ER PT J AU WEGNER, PJ HENESIAN, MA SPECK, DR BIBEAU, C EHRLICH, RB LAUMANN, CW LAWSON, JK WEILAND, TL AF WEGNER, PJ HENESIAN, MA SPECK, DR BIBEAU, C EHRLICH, RB LAUMANN, CW LAWSON, JK WEILAND, TL TI HARMONIC CONVERSION OF LARGE-APERTURE 1.05-MU-M LASER-BEAMS FOR INERTIAL-CONFINEMENT FUSION-RESEARCH SO APPLIED OPTICS LA English DT Article DE INERTIAL-CONFINEMENT FUSION; NOVA LASER FACILITY; ND-GLASS LASER; HARMONIC CONVERSION ID RAMAN-SCATTERING; GLASS LASERS AB To provide high-energy, high-power beams at short wavelengths for inertial-confinement fusion experiments, we routinely convert the 1.05-mum output of the Nova, Nd:phosphate-glass, laser system to its second- or third-harmonic wavelength. We describe the design and performance of the 3 x 3 arrays of potassium dihydrogen phosphate crystal plates used for type-II-type-II phase-matched harmonic conversion of the Nova 0.74-m diameter beams. We also describe an alternate type-I-type-II phase-matching configuration that improves third-harmonic conversion efficiency. These arrays provide conversion of a Nova beam of up to 75% to the second harmonic and of up to 70% to the third harmonic. RP WEGNER, PJ (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 5508,L-493,LIVERMORE,CA 94550, USA. NR 32 TC 31 Z9 46 U1 0 U2 8 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD OCT 20 PY 1992 VL 31 IS 30 BP 6414 EP 6426 PG 13 WC Optics SC Optics GA JR914 UT WOS:A1992JR91400007 PM 20733856 ER PT J AU CHEN, TW SMITH, WS AF CHEN, TW SMITH, WS TI LARGE-ANGLE LIGHT-SCATTERING AT LARGE SIZE PARAMETERS SO APPLIED OPTICS LA English DT Article ID GENERALIZED EIKONAL APPROXIMATION; LARGE PARTICLES; PICTURE AB The generalized eikonal amplitude for light scattering at large size parameters by a dielectric sphere is modified to account more rigorously for the phase-change difference caused by the presence, of the medium. The resulting amplitude is shown to work well for scattering at large angles. It accurately predicts the positions of maxima and minima for scattering angles up to 60-degrees for perpendicularly polarized light. C1 LOS ALAMOS NATL LAB,GEOANAL GRP,LOS ALAMOS,NM 87544. RP CHEN, TW (reprint author), NEW MEXICO STATE UNIV,DEPT PHYS,LAS CRUCES,NM 88003, USA. NR 8 TC 8 Z9 8 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD OCT 20 PY 1992 VL 31 IS 30 BP 6558 EP 6560 PG 3 WC Optics SC Optics GA JR914 UT WOS:A1992JR91400025 PM 20733874 ER PT J AU GRADWOHL, BA FRIEMAN, JA AF GRADWOHL, BA FRIEMAN, JA TI DARK MATTER, LONG-RANGE FORCES, AND LARGE-SCALE STRUCTURE SO ASTROPHYSICAL JOURNAL LA English DT Article DE DARK MATTER; COSMOLOGY, THEORY; EARLY UNIVERSE; ELEMENTARY PARTICLES; LARGE-SCALE STRUCTURE OF UNIVERSE ID REDSHIFT-DISTANCE SAMPLES; MICROWAVE BACKGROUND ANISOTROPIES; DENSITY FIELDS; EQUIVALENCE PRINCIPLE; ELLIPTICAL GALAXIES; STREAMING MOTIONS; GOLDSTONE BOSONS; GALACTIC HALOS; MISSING MASS; COMA CLUSTER AB If the dark matter in galaxies and clusters is nonbaryonic, it can interact with additional long-range fields that are invisible to experimental tests of the equivalence principle. We discuss the astrophysical and cosmological implications of a long-range force coupled only to the dark matter and find rather tight constraints on its strength. If the force is repulsive (attractive), the masses of galaxy groups and clusters (and the mean density of the universe inferred from them) have been systematically underestimated (overestimated). Such an interaction also has unusual implications for the growth of large-scale structure: a repulsive (attractive) force relatively enhances (suppresses) the growth of density perturbations on large scales and automatically generates a bias (antibias) between baryonic and nonbaryonic matter. We explore the consequent effects on the two-point correlation function, large-scale velocity flows, and microwave background anisotropies, for models with initial scale-invariant adiabatic perturbations and cold dark matter. C1 NASA,FERMI NATL ACCELERATOR LAB,FERMILAB ASTRPHYS CTR,BATAVIA,IL 60510. NR 83 TC 66 Z9 66 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 OCT 20 PY 1992 VL 398 IS 2 BP 407 EP 424 DI 10.1086/171865 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JR890 UT WOS:A1992JR89000001 ER PT J AU SAIZAR, P STARRFIELD, S FERLAND, GJ WAGNER, RM TRURAN, JW KENYON, SJ SPARKS, WM WILLIAMS, RE STRYKER, LL AF SAIZAR, P STARRFIELD, S FERLAND, GJ WAGNER, RM TRURAN, JW KENYON, SJ SPARKS, WM WILLIAMS, RE STRYKER, LL TI A MULTIWAVELENGTH STUDY OF NOVA-QU-VULPECULAE 1984 SO ASTROPHYSICAL JOURNAL LA English DT Article DE NOVAE; CATACLYSMIC VARIABLES; STARS, ABUNDANCES; STARS, INDIVIDUAL (QU VUL); ULTRAVIOLET, STARS ID CLASSICAL NOVAE; NEON NOVA; ABUNDANCES; LINES; AL-26; EXPLOSIONS; DISCOVERY; OUTBURSTS; NUMBER-2; EMISSION AB We have combined ground-based optical and satellite ultraviolet spectrophotometric data to study the ejected shell of Nova Vulpecula 1984 No. 2 (QU Vul). Substantial uncertainties concerning the nature of the ionizing continuum, and the role played by density inhomogeneities, now exist. Because of these uncertainties, the chemical composition is deduced from emission-line pairs chosen to minimize the effects of variations in temperature, density, and ionization. We find that the chemical composition of the ejected shell show enhancements of several elements relative to hydrogen, namely, He, N, O, Ne, Mg, Al, and Si, as is expected for an outburst occurring on an ONeMg white dwarf. An almost featureless continuous spectrum and high-ionization lines suggest that a very hot "coronal-line" region is also present, which may contribute to the ionization of the gas and dominate both the mass and the energetics of the ejecta. The total mass of the ejecta is estimated to lie in the range from 0.2 to 15 x 10(-4) M.. This high value of the ejected mass implies a low white dwarf's mass, which is not expected in ONeMg novae. The above results also show that QU Vul ejected a large amount of aluminum into the interstellar medium, and it is estimated that only a small fraction of slow novae of this type can account for the observed abundance of aluminum in the Galaxy. C1 ARIZONA STATE UNIV,DEPT PHYS & ASTRON,TEMPE,AZ 85287. UNIV CHICAGO,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637. HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138. LOS ALAMOS NATL LAB,DIV APPL THEORET PHYS,LOS ALAMOS,NM 87545. NATL OPT ASTRON OBSERV,CERRO TOLOLO INTER AMER OBSERV,LA SERENA,CHILE. RP SAIZAR, P (reprint author), OHIO STATE UNIV,DEPT ASTRON,COLUMBUS,OH 43210, USA. OI Kenyon, Scott/0000-0003-0214-609X; Ferland, Gary/0000-0003-4503-6333 NR 49 TC 58 Z9 58 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 OCT 20 PY 1992 VL 398 IS 2 BP 651 EP 664 DI 10.1086/171890 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JR890 UT WOS:A1992JR89000026 ER PT J AU FELDMAN, U LAMING, JM MANDELBAUM, P GOLDSTEIN, WH OSTERHELD, A AF FELDMAN, U LAMING, JM MANDELBAUM, P GOLDSTEIN, WH OSTERHELD, A TI A BURST MODEL FOR LINE EMISSION IN THE SOLAR ATMOSPHERE .2. CORONAL EXTREME ULTRAVIOLET LINES SO ASTROPHYSICAL JOURNAL LA English DT Article DE ATOMIC DATA; ATOMIC PROCESSES; PLASMAS; SUN, CORONA ID CA-XVII; IONS; EXCITATION; IONIZATION AB We review the spectroscopic evidence for explosive events, hereafter referred to as bursts, occurring in solar coronal plasmas. Problems in the interpretation of extreme ultraviolet spectra from Mg-like ions, particularly Fe XV in solar flares can be obviated to certain extent if these ions are produced in an ionizing plasma, with the 3s3 p 3P levels being excited directly by inner shell ionization of the Al-like ion. We believe that a similar mechanism should apply to Be-like ions. The excitation following inner shell ionization can become important compared to electron impact excitation at a temperature corresponding to approximately twice the ionization potential of the ion concerned, but to be properly effective, it requires some deviation of the electron distribution function from a Maxwellian. In a burst of such a temperature, however, electron impact excitation during the decay phase, assuming radiative cooling of the plasma, will normally make the inner shell contribution insignificant, and so some other means of " switching off " the burst has to be postulated. The model we present produces a coronal heating rate from these bursts that is somewhat larger than current estimates. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP FELDMAN, U (reprint author), USN,RES LAB,EO HULBURT CTR SPACE RES,WASHINGTON,DC 20375, USA. NR 22 TC 31 Z9 31 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 20 PY 1992 VL 398 IS 2 BP 692 EP 697 DI 10.1086/171893 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA JR890 UT WOS:A1992JR89000029 ER PT J AU KIRTLEY, SM MULLINS, OC CHEN, J VANELP, J GEORGE, SJ CHEN, CT OHALLORAN, T CRAMER, SP AF KIRTLEY, SM MULLINS, OC CHEN, J VANELP, J GEORGE, SJ CHEN, CT OHALLORAN, T CRAMER, SP TI NITROGEN CHEMICAL-STRUCTURE IN DNA AND RELATED MOLECULES BY X-RAY ABSORPTION-SPECTROSCOPY SO BIOCHIMICA ET BIOPHYSICA ACTA LA English DT Article DE X-RAY ABSORPTION SPECTROSCOPY; DNA STRUCTURE; HYDROGEN BONDING ID K-SHELL PHOTOABSORPTION; N2; N-2; NO AB The electronic environment of nitrogen in nucleic acid bases, nucleotides, polynucleotides and DNA has been studied, for the first time using X-Ray Absorption Near-Edge Spectroscopy (XANES). Generally, the spectra of these complex molecules consist of low energy bands corresponding to 1s --> pi* transitions and high energy bands corresponding to 1 s --> sigma* transition, as illustrated using several nitrogen model compounds. The 1s --> pi* transitions show particular sensitivity to the chemical environment of the nitrogen. Oxygen substitution on ring carbon atoms generally results in a significant blue shift of the lowest 1s --> pi* bands while halogen substitution results in a small blue shift. These observations illustrate the significance of the disturbance of the aromatic ring system produced by exocyclic carbonyl groups. Direct substitution on the nitrogen frequently results in significant spectral perturbations. Differences between the spectra of the polynucleotides and the sums of spectra of the individual nucleotides point to the effects of hydrogen-bonding in complementary double-helix structures. The XANES spectrum of a DNA sample with a known ratio of the polynucleotides is equivalent to the weighted sum of the spectra of individual polynucleotides, indicating that the difference in base stacking interactions produces negligible spectral effects. The variability of nitrogen K-edge spectra in these samples and in protein may be useful for chemically specific imaging using X-ray microscopes. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CALIF DAVIS,DAVIS,CA 95616. AT&T BELL LABS,MURRAY HILL,NJ 07974. NORTHWESTERN UNIV,CHICAGO,IL 60611. RP KIRTLEY, SM (reprint author), SCHLUMBERGER DOLL RES CTR,OLD QUARRY RD,RIDGEFIELD,CT 06877, USA. FU NIGMS NIH HHS [GM-44380] NR 14 TC 51 Z9 51 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0006-3002 J9 BIOCHIM BIOPHYS ACTA PD OCT 20 PY 1992 VL 1132 IS 3 BP 249 EP 254 DI 10.1016/0167-4781(92)90157-U PG 6 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA JW756 UT WOS:A1992JW75600003 PM 1420304 ER PT J AU KAO, CYJ TIE, XX MROZ, E CUNNOLD, D ALYEA, F AF KAO, CYJ TIE, XX MROZ, E CUNNOLD, D ALYEA, F TI SIMULATION OF THE GLOBAL CFC-11 USING THE LOS-ALAMOS CHEMICAL TRACER MODEL SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ATMOSPHERIC LIFETIME EXPERIMENT; GENERAL-CIRCULATION MODEL; TRANSPORT; OZONE; CHEMISTRY; EQUATION; CF2CL2; CFCL3; N2O AB A three-dimensional global chemical tracer model (CTM) with a multiyear circulation provided from the Los Alamos general circulation model (GCM) is developed to simulate the distributions and trends of global CFC 11 concentrations. Realistic geographic emission patterns and parameterized photolysis rates are included in the model. The initial condition corresponds to the observed values in July 1978. The results of six model years from July 1979 to June 1985 are presented. Comparisons with the Atmospheric Lifetime Experiment (ALE) observations show reasonable agreement. The intrinsic features of the five ALE sites can be summarized as follows: Adrigole is sensitive to horizontal diffusion because it is located between the European and North American sources; Samoa and Tasmania are heavily influenced by the interhemispheric transport; and Oregon and Barbados require a better resolved flow pattern to receive the transport from their nearest sources. The modeled global budget in terms of interhemispheric burden difference, stratospheric loss rate, interhemispheric transport, and its associated time constant is comparable with that derived from a previous study. A model sensitivity test using a large (approximately 3 times) horizontal diffusion shows that it modestly improves certain aspects of the simulations at southern hemisphere ALE sites, however, at the cost of a greatly reduced interhemispheric burden difference and exchange time constant. C1 GEORGIA INST TECHNOL,ATLANTA,GA 30332. NATL CTR ATMOSPHER RES,BOULDER,CO 80307. RP KAO, CYJ (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544, USA. NR 27 TC 10 Z9 10 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-ATMOS JI J. Geophys. Res.-Atmos. PD OCT 20 PY 1992 VL 97 IS D14 BP 15827 EP 15838 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA JU835 UT WOS:A1992JU83500010 ER PT J AU KIM, KK HWANG, KY JEON, HS KIM, S SWEET, RM YANG, CH SUH, SW AF KIM, KK HWANG, KY JEON, HS KIM, S SWEET, RM YANG, CH SUH, SW TI CRYSTALLIZATION AND PRELIMINARY-X-RAY CRYSTALLOGRAPHIC ANALYSIS OF LIPASE FROM PSEUDOMONAS-CEPACIA SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Note DE LIPASE; PSEUDOMONAS-CEPACIA; CRYSTALLIZATION; X-RAY CRYSTALLOGRAPHY; PRELIMINARY X-RAY ANALYSIS ID GEOTRICHUM-CANDIDUM; PANCREATIC LIPASE; DIFFRACTION DATA; GENE; PROTEINS; PURIFICATION; EXPRESSION; SEQUENCE; DETECTOR; CLONING C1 SEOUL NATL UNIV, COLL NAT SCI, DEPT CHEM, SEOUL 151742, SOUTH KOREA. LUCKY RES & DEV CTR, TAEJON, SOUTH KOREA. BROOKHAVEN NATL LAB, DEPT BIOL, UPTON, NY 11973 USA. RI Suh, Se Won/H-8306-2013 OI Suh, Se Won/0000-0002-1768-4635 NR 32 TC 22 Z9 22 U1 0 U2 1 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD OCT 20 PY 1992 VL 227 IS 4 BP 1258 EP 1262 DI 10.1016/0022-2836(92)90537-T PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA JW721 UT WOS:A1992JW72100025 PM 1279182 ER PT J AU GOLDMAN, T HENDERSON, JA THOMAS, AW AF GOLDMAN, T HENDERSON, JA THOMAS, AW TI SUBSTRUCTURE EFFECT ON RHO-OMEGA MIXING IN CHARGE-SYMMETRY VIOLATION SO MODERN PHYSICS LETTERS A LA English DT Article AB In generating a charge-symmetry breaking potential using rho-omega mixing it is usually assumed that the mixing amplitude is constant (at the on-mass-shell value). Since the exchanged meson is actually far off-shell one must question the validity of this assumption. By constructing a simple quark model in which the mixing is generated by the u-d quark mass difference, we find that the assumption seems to be a very poor one. RP GOLDMAN, T (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. RI Thomas, Anthony/G-4194-2012 OI Thomas, Anthony/0000-0003-0026-499X NR 0 TC 14 Z9 14 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 OCT 20 PY 1992 VL 7 IS 32 BP 3037 EP 3043 DI 10.1142/S0217732392002421 PG 7 WC Physics, Nuclear; Physics, Particles & Fields; Physics, Mathematical SC Physics GA JT822 UT WOS:A1992JT82200010 ER PT J AU ABRIKOSOV, AA AF ABRIKOSOV, AA TI TUNNELING CONDUCTANCE OF THE S-N LAYERED MODEL OF HTSC SO PHYSICA C LA English DT Article ID SUPERCONDUCTORS AB The tunneling conductance G(V) = dJ/dV is analyzed for the layered S-N model of a high-temperature superconductor. In order to fit the qualitative features of the experimental data, it was assumed that the tunneling probability to the normal layers is much less than to the superconducting layers. The conductance is calculated for the case t << DELTA, t being the interlayer hopping energy. A brief analysis is given for the case t is-similar-to DELTA, which proves that such an assumption definitely contradicts the experimental data. The possible nature of the electronic states in the normal layers is discussed. RP ABRIKOSOV, AA (reprint author), ARGONNE NATL LAB,DIV MAT SCI,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 7 TC 8 Z9 8 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 OCT 20 PY 1992 VL 201 IS 3-4 BP 413 EP 420 DI 10.1016/0921-4534(92)90492-U PG 8 WC Physics, Applied SC Physics GA JW509 UT WOS:A1992JW50900024 ER PT J AU WOLF, D JASZCZAK, JA AF WOLF, D JASZCZAK, JA TI ON THE INTERACTION BETWEEN STEPS IN VICINAL FCC SURFACES .1. STEPS ALONG (001) SO SURFACE SCIENCE LA English DT Article ID CRYSTAL FLUID INTERFACE; EMBEDDED-ATOM METHOD; GRAIN-BOUNDARIES; MOLECULAR-DYNAMICS; PHASE-TRANSITIONS; ELASTIC-CONSTANTS; FREE-ENERGIES; SYSTEMS; METALS; DIFFRACTION AB Atomistic computer simulations are used to study the zero-temperature interaction between steps in vicinal free fcc surfaces in order to test the continuum-elastic theory of Marchenko and Parshin (MP). Two different types of surface steps, both parallel to [001] but situated, respectively, on the (100) and (110) planes, are investigated using two qualitatively different interatomic potentials, one of the embedded-atom-method type and the other the Lennard-Jones potential. In agreement with the MP theory, for the largest step separations delta the energy due to the step-step repulsion is found to decrease as delta-2, with a strength given by the surface-stess tensor and the elastic moduli of the material. Surprisingly, for both potentials and for both types of steps the delta-2 power law appears to be obeyed even for the smallest step separations, albeit with a 2-3 times smaller interaction strength. The relationship of our simulation results with a nearest-neighbor broken-bond model is also explored. C1 MICHIGAN TECHNOL UNIV,DEPT PHYS,HOUGHTON,MI 49931. RP WOLF, D (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. NR 42 TC 19 Z9 19 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD OCT 20 PY 1992 VL 277 IS 3 BP 301 EP 322 DI 10.1016/0039-6028(92)90770-7 PG 22 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA JU938 UT WOS:A1992JU93800014 ER PT J AU LAI, B YUN, WB LEGNINI, D XIAO, Y CHRZAS, J VICCARO, PJ WHITE, V BAJIKAR, S DENTON, D CERRINA, F DIFABRIZIO, E GENTILI, M GRELLA, L BACIOCCHI, M AF LAI, B YUN, WB LEGNINI, D XIAO, Y CHRZAS, J VICCARO, PJ WHITE, V BAJIKAR, S DENTON, D CERRINA, F DIFABRIZIO, E GENTILI, M GRELLA, L BACIOCCHI, M TI HARD X-RAY PHASE ZONE PLATE FABRICATED BY LITHOGRAPHIC TECHNIQUES SO APPLIED PHYSICS LETTERS LA English DT Article ID MICROPROBE AB A Fresnel phase zone plate with an unprecedented focusing efficiency of 33% was fabricated using an x-ray lithographic technique and was tested using synchrotron x rays. Contributions by the zeroth-order x ray to the focus were minimal. Spatial resolution in the micrometer range was achieved. The measured spot size was dominated by geometric demagnification of the source. It should be possible to obtain submicrometer resolution by aperturing the source. Experimental results of focusing efficiency measurements, intensity distribution at the focal plane, and spatial resolution tests are reported. C1 UNIV WISCONSIN,CTR XRAY LITHOG,STOUGHTON,WI 53589. INST SOLID STATE ELECTR,ROME,ITALY. RP LAI, B (reprint author), ARGONNE NATL LAB,ADV PHOTON SOURCE,ARGONNE,IL 60439, USA. NR 14 TC 93 Z9 94 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 19 PY 1992 VL 61 IS 16 BP 1877 EP 1879 DI 10.1063/1.108400 PG 3 WC Physics, Applied SC Physics GA JT884 UT WOS:A1992JT88400001 ER EF