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CreatorTitleDescriptionSubjectDate
401 Williams, Clayton C.Single electron tunneling force spectroscopy of an individual electronic state in a non-conducting surfaceA tunneling spectroscopy technique to measure the energy level of an electronic state in a completely nonconducting surface is demonstrated. Spectroscopy is performed by electrostatic force detection of single-electron tunneling between a scanning probe and the state as a function of an applied vo...Tunneling; Spectroscopy; Single electron; Scanning tunneling microscope2006
402 Wu, Yong-ShiDynamics of giant-gravitons in the LLM geometry and the fractional quantum Hall effectThe LLM's 1/2 BPS solutions of IIB supergravity are known to be closely related to the integer quantum Hall droplets with filling factor v = 1, and the giant gravitons in the LLM geometry behave like the quasi-holes in those droplets. In this paper we consider how the fractional quantum Hall effect ...2006
403 Gondolo, PaoloEffects of the Sagittarius dwarf tidal stream on dark matter detectorsThe Sagittarius dwarf tidal stream may be showering dark matter onto the solar neighborhood, which can change the results and interpretation of direct detection searches for weakly interacting massive particles (WIMPs). Stars in the stream may already have been detected in the solar neighborhood, an...Sagittarius dwarf galaxy; Sgr stream; WIMP; Weakly interacting massive particles2004-03
404 Vardeny, Zeev ValentineAbsorption studies of charged excitations in α-sexithiopheneWe present photoexcitation studies of vacuum deposited neutral films of α,ω-substituted sexithiophene (α-6T) using photoinduced absorption (PA) and PAdetected magnetic resonance spectroscopy (PADMR). We find evidence for photoinduced polarons having spin 1/2, with two absorption bands at 0.80...alpha- sexithiophene; Charged excitations; Photoexcitation; Photoinduced absorption1996
405 Capecchi, Mario R.Expression of a microinjected porcine class I major histocompatibility complex gene in transgenic mice.A porcine class I major histocompatibility complex (SLA) gene has been introduced into the genome of a C57BL/10 mouse. This transgenic mouse expressed SLA antigen on its cell surfaces and transmitted the gene to offspring, in which the gene is also expressed. Skin grafts of such transgenic mice were...Genetic Engineering; Graft Rejection; Mice, Inbred C57BL1985-05-03
406 Golden, Kenneth M.Electrical transport in high contrast composite materialsA broad range of problems in the physics of materials involve highly disordered media whose effective behavior depends critically on the connectedness, or percolation properties of a particular component. Examples include smart materials such as piezoresistors and thermistors, smart insulators, rada...1997
407 Coley, Phyllis D.Coibanoles, a new class of meroterpeniods produced by pycnoporus sanguineusThree new terpenoids of mixed biosynthetic origin were isolated from the culture filtrate of the endophytic fungus Pycnoporus sanguineus. Their structures were determined by extensive spectroscopic analyses. We have named these tricyclic and tetracyclic metabolites ?coibanoles A?C? in reference to...2012
408 Sokolsky, PierreSearch for new particles at the alternating-gradient-synchrotron beam dumpThis paper presents results of a beam-dump experiment performed at the Brookhaven alternating-gradient synchrotron to search for prompt sources of neutrinos and axionlike particles. We observe no excess of vµ or events, and no excess in neutral-current events over that expected from neutrinos from ...1979-05
409 Golden, Kenneth M.Convexity and exponent inequalities for conduction near percolationThe bulk conductivity o*(p) of the bond lattice in Zd with a fraction p of conducting bonds is analyzed. Assuming a hierarchical node-link-blob (NLB) model of the conducting backbone, it is shown that o*(p) (for this model) is convex in p near the percolation threshold pc, and that its critical expo...Lattice; Conductivity; Model1990
410 Olivera, Baldomero M.Conodipine-M, a novel phospholipase A2 isolated from the venom of the marine snail Conus magusWe describe the purification and first biochemical characterization of an enzymatic activity in venom from the marine snail Conus magus. This enzyme, named conodipine-M, is a novel phospholipase A2 with a molecular mass of 13.6 ĸDa and is comprised of two polypeptide chains linked by one or more di...Conotoxins; Conodipine-M; Conus magus1994
411 Olivera, Baldomero M.Identification of Conus peptidylprolyl cis-trans isomerases (PPIases) and assessment of their role in the oxidative folding of conotoxinsPeptidylprolyl cis-trans isomerases (PPIases) are ubiquitous proteins that catalyze the cis-trans isomerization of prolines. A number of proteins, such as Drosophila rhodopsin and the human immunodeficiency viral protein HIV-1 Gag, have been identified as endogenous substrates for PPIases. However, ...2010
412 Wu, Yong-ShiAnyons on a torus: braid group, Aharonov-Bohm period, and numerical studyWe present a careful construction of anyons on a torus starting with the braid-group analysis. The rules of Wen, Dagotto, and Fradkin for putting anyons on a torus are reproduced with some minor improvements. The existence of noncontractible loops leads to braid-group representations characterized n...Braid group; Magnetic flux1991-05
413 Vardeny, Zeev ValentineCooperative emission in ∏-conjugated polymer thin filmsPicosecond dynamics of exciton emission and absorption have been studied in neat thin films of a variety of poly (phenylene vinylene) derivatives. We found that the stimulated emission band of 120 nm width and ~1 ns duration, which is observed at low exciton density n, collapses at n > 1017 cm-3 int...Pi-conjugated polymers; Poly (phenylene vinylene) derivatives; PPV derivatives; Cooperative emission1997-01
414 Olivera, Baldomero M.Poly(ADP-ribosylation) of DNA topoisomerase I: a nuclear response to DNA-strand interruptionsDNA in eukaryotic chromosomes is organized differently from prokaryotic DNA. It seems highly probable that mechanistic adjustments have been made in macromolecular DNA metabolism as a consequence of the chromatin structure of the eukaryotic chromosome (Igo-Kemenes et al. 1982)). This paper deals ...Poly(ADP-ribosylation); Poly(ADP-ribose) synthetase; DNA strand interruption1984
415 Gondolo, PaoloNeutralino with the right cold dark matter abundance in (almost) any supersymmetric modelWe consider nonstandard cosmological models in which the late decay of a scalar field Ø reheats the Universe to a low reheating temperature, between 5 MeV and the standard freeze-out temperature of neutralinos of mass mx. We point out that in these models all neutralinos with standard density Ώstd...Neutralinos; Reheating temperature2006-07
416 Morse, Michael DavidSpectroscopy of AlAr and AlKr from 31 000 cm-1 to the ionization limitSpectra of jet-cooled AlAr and AlKr have been collected over the range from 31 000 cm -? to the ionization limit, using the technique of resonant two-photon ionization spectroscopy with mass spectrometric detection. Adiabatic ionization potentials have been accurately measured for both molecules, an...1992
417 Vardeny, Zeev ValentinePhotoinduced absorption spectra in α-GeH and α-Si:HMeasurements of steady-state photoinduced absorption in α-Ge:H and α-Si:H were extended to cover the energy range from 0.25 to 1.9 eV. The subgap photoinduced-absorption bands in both materials are interpreted in terms of four kinds of optical transitions of photogenerated carriers from traps in ...Photoinduced absorption; in a-GeH; a-Si:H; Amorphous germanium; Amorphous silicon1984-07
418 Boehme, ChristophDiffusion of hydrogen and deuterium in stack systems of SixNyHz/SixNyDz and crystalline SiH/D-, N-H/D- and Si-H/D-bond density changes were investigated in stacks consisting of a Cz-Si substrate, a thin layer of SiC>2, amorphous deuterated silicon nitride as well as amorphous hydrogenated silicon nitride in order to see if the post deposition anneal of a-SixNyHz layers on crystalline sil...Hydrogenated silicon nitride; Anneal process2000
419 Morse, Michael DavidResonant two-photon ionization spectroscopy of LiCuJet-cooled LiCu has been investigated using resonant two-photon ionization spectroscopy. A long vibrational progression was observed and identified as the [20.5] 1?+? X 1?+ band system. Ten bands of the system were rotationally resolved for 7Li63Cu, giving bond lengths of r0=2.2618(3) ? for the X 1?...1997
420 Clayton, Dale H.Swiftlets on islands: genetics and phylogeny of the Seychelles and Mascarene swiftletsPopulations on islands are isolated from mainland populations and are thus expected to diverge and speciate from mainland relatives. We investigated die phylogenetic position and taxonomic rank of the Seychelles and Mascarene swiftlets using nuclear (fibrinogen intron 7) and mitochondrial (cytochr...Aerodramus Francicus; Aerodramus elaphrus; Collocalia; Apodidae; Cytochrome b; Fibrinogen intron 7; Echolocation; Seychelles; Mascarene Islands1999
421 Miller, Joel Steven; Epstein, Arthur J.Evidence for solitons in conducting organic charge-transfer crystalsMagnetic susceptibility of (N-methylphenazinium)x(phenazine)(1-x (tetracyanoquinodimethanide) [(NMP)x(Phen)1-x(TCNQ)] shows the formation of defect states for 0.5<x<0.54. Diffuse x-ray scattering and g-value studies indicate that these defects are solitons formed in the highly correlated quasi-one-...TCNQ; X-ray scattering1982
422 Ehleringer, James R.Gas exchange, δ13C, and heterotrophy for Castilleja linariifolia and Orthocarpus tolmiei, facultative root hemiparasites on Artemisia tridentataGas exchange and carbon isotope ratios were measured on 2 facultative hemiparasites, Castilleja linarifolia Benth. (Indian paintbrush; Scrophulariaceae) and Orthocarpus tolmiei I-I. & A. (Tolmie owl clover; Scrophulariaceae), and their Artemisia tridentata L. (big sagebrush; Asteraceae) hosts. Photo...Heterotrophy; Hemiparasite; Carbon isotope ratios; Shrub ecology; Castilleja linarifolia; Orthocarpus tolmiei; Artemisia tridentata1996
423 Lupton, John MarkRoom-temperature exciton storage in elongated semiconductor nanocrystalsThe excited state of colloidal nanoheterostructures consisting of a spherical CdSe nanocrystal with an epitaxially attached CdS rod can be perturbed effectively by electric fields. Field-induced fluorescence quenching coincides with a conversion of the excited state species from the bright exciton ...Exciton storage; Colloidal nanoheterostructures; CdSe nanocrystal2007-01
424 Vardeny, Zeev ValentineEvolution of excitons and polarons in polythiophene from femtoseconds to millisecondsWe have studied the photoexcitation dynamics in electrochemically polymerized polythiophene thin films using transient photomodulation spectroscopy measured from 100 fs to 20 ms in the spectral range from 0.25 to 2.2 eV, and by the novel technique of absorption-detected magnetic resonance (ADMR). ...Femtoseconds; Milliseconds; Photoexcitation dynamics1992-07
425 Vardeny, Zeev ValentinePhotogeneration and recombination processes of neutral and charged excitations in films of a ladder-type poly(para-phenylene)We introduce a version of the cw photomodulation technique, measured far from the steady state, for obtaining the quantum efficiency, η, of long-lived photoexcitations in p-conjugated polymers. We apply this technique to films of a ladder-type poly(para-phenylene) [mLPPP] for studying the photoge...Photogeneration; Recombination process; Neutral excitations; Charged excitations; Ladder-type poly(para-phenylene)1999-08
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