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CreatorTitleDescriptionSubjectDate
326 Gondolo, PaoloDetectability of weakly interacting massive particles in the Sagittarius dwarf tidal streamTidal streams of the Sagittarius dwarf spheroidal galaxy (Sgr) may be showering dark matter onto the solar system and contributing ~(0:3-23)% of the local density of our galactic halo. If the Sagittarius galaxy contains dark matter in the form of weakly interacting massive particles (WIMPs), the ext...WIMP; Weakly interacting massive particles; Sagittarius dwarf galaxy; Recoil energy; Sgr stream2005-02
327 Miller, Joel Steven; Epstein, Arthur J.Spin dilution in a ferromagnetic chainWe have systematically introduced spinless defects in the quasi-one-dimensional ferromagnetic system decamethylferrocenium tetracyanoethanide, [FeCp(2*)] [TCNE]. The three-dimensional ordering temperature Tc decreases rapidly with the concentration of spinless sites. The rate of decrease of Tc with...Magnetic; Magnetization; Spinless1992
328 Vardeny, Zeev ValentinePhotophysics of pristine and C60-doped disubstituted polyacetyleneUsing a variety of steady-state spectroscopies we studied the long-lived photoexcitations and electronic excited states of poly disubstituted acetylene (PDPA-nBu), the backbone structure of which is a disubstituted trans-polyacetylene, as well as PDPA-nBu/C60 blends. The cw spectroscopies include a...Photophysics; Pristine disubstituted polyacetylene; C60-doped disubstituted polyacetylene; pi-conjugated polymers; Photoexcitations; Electronic excited states2002-08
329 Shapiro, Michael D.Genetic architecture of parallel armor plate reduction in threespine sticklebacksHow many genetic changes control the evolution of new traits in natural populations? Are the same genetic changes seen in cases of parallel evolution? Despite long-standing interest in these questions, they have been difficult to address, particularly in vertebrates. We have analyzed the genetic bas...Genetic changes; Plate number; Genetic mapping2004
330 Hultine, Kevin; Sperry, John S.Transpiration and hydraulic strategies in a piñon-juniper woodlandAnthropogenic climate change is likely to alter the patterns of moisture availability globally. The consequences of these changes on species distributions and ecosystem function are largely unknown, but possibly predictable based on key ecophysiological differences among currently coexisting species...Drought; Hydraulic transport model; Juniperus osteosperma; Plant water use; Sap flux; Species distributions2008
331 DeTar, CarletonConjecture concerning the modes of excitation of the quark-gluon plasmaIt is a widely held belief that at temperatures much higher than the confinement scale of quantumchromodynamics (QCD), quarks and gluons become free, giving rise to a new form of matter, called the quark-gluon plasma. It is conjectured here that the characterization of the plasma as a free or weakl...Polyakov loops; Excitation1985-07
332 Clayton, Dale H.Neotropical tineidae, II: biological notes and descriptions of two new moths phoretic on spiny pocket mice in Costa Rica (Lepidoptera: Tineoidea)Two new species of tineid moths discovered riding on the backs of two species of spiny pocket mice (Heteromyidae) in Costa Rica are described. Amydria selvae, new species, was found on Heteromys desmarestianus Gray in the rainforest at Finca La Selva and Ptilopsaltis santarosae, new species, occurr...Neotropical Tineidae; Phoretic moths; Amydria selvae; Heteromys desmarestianus; Ptilopsaltis santarosae; Liomys salvini; Mouse moths1986
333 Vardeny, Zeev ValentinePhotocarrier dynamics in compensated hydrogenated amorphous siliconThe photocarrier dynamics in compensated a-Si:H is studied using the time-dependent photomodulation technique in the subpicosecond-to-millisecond time range. We find that photocarriers are quickly trapped in shallow impurity levels for t < 10 psec, similar to the behavior in singly doped materials...Photocarriers; a-Si:H; Amorphous silicon; Fast trapping1986-03
334 Clayton, Dale H.Two new species of Dennyus (Collodennyus) chewing lice (Phthiraptera: Amblycera: Menoponidae) from swiftlets (Apodiformes: Apodidae)The new species Dennyus (Collodennyus) mimirogerorum from the Papuan swiftlet, Aerodramus papuensis (Rand), from Papua New Guinea and D. (C.) bartoni from the Philippine swiftlet, A. mearnsi (Oberholser), from the Philippines are described and illustrated. The genetic distinctiveness of these two sp...Collodennyus; Chewing louse; Chewing lice; Swiftlets; Phthiraptera; Papuan swiftlet; Aerodramus papuensis2006
335 Vardeny, Zeev ValentineAmplified spontaneous emission and lasing in conducting polymers and fluorescent dyes in opals as photonic crystalsSpectral narrowing of photoluminescence (PL) and evolution of sharp emission lines upon optical excitation have been observed in opals made of SiO2 spheres infiltrated with conducting polymers such as OOPPV and MDDOPPV and also fluorescent dyes such as rhodamine 6G, NK-3483, and coumarin 120. Their ...Amplified spontaneous emission; Lasing; Fluorescent dyes1999
336 Wu, Yong-ShiTwo-loop analysis of non-Abelian Chern-Simons theoryPerturbative renormalization of a non-Abelian Chern-Simons gauge theory is examined. It is demonstrated by explicit calculation that, in the pure Chern-Simons theory, the & function for the coefficient of the Chern-Simons term vanishes to three-loop order. Both dimensional regularization and regula...Chern-Simons theory; Yang-Mills theory; Regularization1992-12
337 Ailion, David Charles14N study of the role of N-D---O bonds in the deuteron glass transition14N spin-lattice relaxation-time measurements in Rb0.28(ND4)0.72D2PO4 provide direct evidence for the fast exchange averaging of the "long" and "short" N-D---O hydrogen bonds between the ND4 group and the four surrounding PO4 groups. This exchange and the associated distortion of the ND4 tetrahedron...NMR; Hydrogen bonds; Spin-lattice; Relaxation-time; Deuteron glass1999
338 Vardeny, Zeev ValentineStudies of polymer microring lasers subject to uniaxial stressThe emission spectra of microring lasers fabricated from ∏-conjugated polymer films casted on nylon microfibers with diameters in the range of 35-90 µm were studied upon application of uniaxial stress with strain up to ~12%. The laser emission spectra substantially change with the applied stress,...pi-conjugated polymers; Microring lasers; Uniaxial stress; DOO-PPV2007
339 Olivera, Baldomero M.; Ireland, Chris M.NMR structures of conotoxinsThis review discusses the methodology, structural details, and biological implications regarding NMR structures of conotoxins. NMR and molecular modeling techniques have improved to the point that three-dimensional structures of conotoxins can now be determined with a significant degree of confiden...Conotoxins1996
340 Williams, Clayton C.Two step dopant diffusion study performed in two dimensions by scanning capacitance microscopy and TSUPREM IVWe report the results of a two-step two- dimensional (2D) diffusion study by scanning capacitance microscopy (SCM) and 2D SUPREM IV process simulation. A quantitative 2D dopant profile of a gate-like structure is measured with the SCM on a cross-sectioned polished silicon wafer. The gate-like struct...Scanning capacitance microscopy; SCM; Doping1998
341 Morse, Michael DavidRotationally resolved spectra of Pt?High-resolution laser-induced fluorescence spectroscopy has been used to investigate the 18 163 cm21 band of Pt2 in a supersonically cooled molecular beam. Rotational constants of the ground and excited states were extracted from the rotationally resolved spectrum and determined to be B0'=0.031 754(...2002
342 Wu, Yong-ShiOne-loop shift in noncommutative Chern-Simons couplingIn this paper we study the one-loop shift in the coupling constant in a noncommutative pure U(N) Chern-Simons gauge theory in three dimensions. The one-loop shift is shown to be a constant proportional to N, independent of noncommutativity parameters, and non-vanishing for U(1) theory. Possible phy...2001-01
343 Gerton, JordanScattering of plasmons at the intersection of two metallic nanotubes: implications for tunnelingWe study theoretically the plasmon scattering at the intersection of two metallic carbon nanotubes. We demonstrate that, for a small angle of crossing θ « 1, the transmission coefficient is an oscillatory function of θ / λ, where ω is the interaction parameter of the Luttinger liquid in an ind...2008-12
344 Golden, Kenneth M.Forward electromagnetic scattering models for sea iceRecent advances in forward modeling of the electromagnetic scattering properties of sea ice are presented. In particular, the principal results include the following: 1) approximate calculations of electromagnetic scattering from multilayer random media with rough interfaces, based on the distorte...Polar ice; Electromagnetic scattering; Electromagnetic scattering forward problems; Multilayer random media; Dielectric materials; Nonhomogeneous media; Remote sensing1998
345 Vardeny, Zeev ValentineResonant-Raman-scattering studies of disorder in solution-cast polydiacetylene filmsThe disorder in polydiacetylene films cast from solution is studied by Raman scattering under preresonance and resonance conditions in both Stokes and anti-Stokes configurations. The disorder-induced inhomogeneities in the exciton energy levels and the strongly coupled vibrations cause strong disper...Polydiacetylene films; Stokes configuration1990-08
346 Lupton, John MarkTime delayed electroluminescence overshoot in single layer polymer light-emitting diodes due to electrode luminescence quenchingWe investigate the transient response of single layer polymer light-emitting diodes (LEDs) based on poly[2-methoxy, 5-(2'ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV). An electroluminescence overshoot is observed between 1 and 2 μs after turning off the voltage pulse, depending on temperature...MEH-PPV; Delayed electroluminescence; Overshoot; Single layer; Electrode luminescence quenching; Transient responses2001
347 Gondolo, PaoloImplications of muon anomalous magnetic moment for supersymmetric dark matterThe anomalous magnetic moment of the muon has recently been measured to be in conflict with the standard model prediction with an excess of 2.6s. Taking the excess at face value as a measurement of the supersymmetric contribution, we find that at 95% confidence level it imposes an upper bound of 50...Magnetic moment; Neutralinos2001-05
348 Armentrout, Peter B.Effect of kinetic and electronic energy on the reactions of Mn+ with H2, HD and D2Reactions of several electronic states of Mn+ with H2, HD, and D2 have been examined using guided ion beam mass spectroscopy. The excitation function for the ground state of Mn+ ( 75) has two regions: one of very low reactivity at threshold and another more efficient pathway at higher energies. In ...Ion-molecule reactions; Translational energy; Bond energy; Threshold behavior; Endothermic reactions; Metal ions; Manganese; Hydrogen1986
349 Vardeny, Zeev ValentineSymmetric light emitting divices from poly(p-di ethynylene phenylene) (p-di phenylene vinylene) derivativesLight emitting devices were fabricated from 2,5-dialkoxy derivatives of poly(p-di ethynylene phenylene-p-di phenylene vinylene) (PDEPDPV) sandwiched between indium tin oxide (ITO) and Al. The current-voltage (Iel-V) curve, electroluminescence (EL) intensity-voltage (IEL-V) curve, and the EL spectra ...Poly(p-di ethynylene phenylene); PPV; Pi-conjugated polymers1995
350 Dawson, KyleRadiation tolerance of high-resistivity LBNL CCDsThick, fully-depleted p-channel charge-coupled devices (CCDs) have been developed at the Lawrence Berkeley National Laboratory (LBNL). These CCDs have several advantages over conventional n-channel CCDs, including enhanced quantum efficiency and reduced fringing at near-infrared wavelengths, a smal...P-Channel CCDs; Astrophysics instrumentation; Space instrumentation; SNAP satellite; Space-based telescopes2006-10
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