UScholar Works
 
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CreatorTitleDescriptionSubjectDate
251 DeTar, CarletonLattice calculation of heavy-light decay constants with two flavors of dynamical quarksWe present results for f B , f Bs , f D , f Ds and their ratios in the presence of two flavors of light sea quarks (Nf52). We use Wilson light valence quarks and Wilson and static heavy valence quarks; the sea quarks are simulated with staggered fermions. Additional quenched simulations with nonpe...Wilson quarks; Chiral perturbation2002-11
252 Boehme, ChristophLong-lived spin coherence in silicon with an electrical spin trap readoutPulsed electrically detected magnetic resonance of phosphorous (31P) in bulk crystalline silicon at very high magnetic fields (B0 > 8:5 T) and low temperatures (T = 2:8 K) is presented. We find that the spin-dependent capture and reemission of highly polarized (>95%) conduction electrons by equall...Spin coherence2008-11
253 Rogachev, AndreyObservation of shot noise in phosphorescent organic light-emitting diodesWe employed a cross correlation method to study current noise in phosphorescent organic light-emitting diodes. The noise spectra revealed two frequency-dependent components. The first component displays 1/ f 1.3 dependence and correlates with the light emission of the devices. The second component i...2014-01-01
254 Truong, ThanhReaction class transition state theory: hydrogen abstraction reactions by hydrogen atoms as test casesWe present a new method called Reaction Class Transition State Theory (RC-TST) for estimating thermal rate constants of a large number of reactions in a class. This method is based on the transition state theory framework within the reaction class approach. Thermal rate constants of a given reacti...Transition state theory; Hydrogen2000
255 Vardeny, Zeev ValentineTransient photomodulation spectroscopy of nanocrystalline hydrogenated siliconTransient photomodulation spectra were measured on nanocrystalline Si:H films in the time domain from 10-7 to 10-2 s, spectral range from 0.25 to 1.25 eV, and temperature range from 80 to 300 K. The properties of the spectra are compatible with the presence of two phases, amorphous and crystalline. ...Transient photomodulation spectroscopy; Nanocrystalline silicon1989-03
256 Ailion, David CharlesNMR relaxation study of molecular motions between unequal potential wells in solid trans, trans- muconodinitrileWe report observations of extremely unusual proton NMR relaxation rates in solid trans, transmuconodinitrile (TMD, N=C-CH = CH-CH = CH-C = N). In particular we measured, over the temperature range 77-423 °K, proton dipolar relaxation times Tw and spin lattice relaxation times Tt (at 24 and 58 MH...NMR; Nuclear magnetic resonance; Lattices; Relaxation time1977
257 Bowling, David R.Ecological processes dominate the 13C land disequilibrium in a Rocky Mountain subalpine forestFossil fuel combustion has increased atmospheric CO2 by ≈ 115 μmol mol1 since 1750 and decreased its carbon isotope composition (δ13C) by 1.7-2‰(the 13C Suess effect). Because carbon is stored in the terrestrial biosphere for decades and longer, the δ13C of CO2 released by terrestrial ecosyst...2014-01-01
258 Armentrout, Peter B.Translational energy dependence of Ar+ + XY → ArX+ + Y (XY = H2, D2, HD) from thermal to 30 eV c.m.Cross sections for the reactions of Ar+ with H2, D2, and HD to form ArH + and ArD + are measured using a new guided ion beam tandem mass spectrometer which affords an experimental energy range from 0.05 to 500 eV laboratory. The apparatus and experimental techniques are described in detail. Cross se...Translational energy; Ion-molecule reactions; Ion energy; Argon; Hydrogen; Endothermic reactions1985
259 Armentrout, Peter B.Theoretical investigation and reinterpretation of the decomposition of lithiated proline and N-Methyl ProlineLithium cation complexes of proline (Pro) and N-methyl proline (NMP) have been collisionally activated with xenon in a guided ion beam tandem mass spectrometer (GIBMS). In addition to the loss of the intact ligand, Pro and NMP, we observed two prominent fragmentation pathways involving the loss of (...2014-01-01
260 Sokolsky, PierreHighest-energy cosmic raysWhat in the cosmos can possibly be accelerating protons to 1020 electron volts and beyond? And how can they preserve such extreme energies while plowing through the cosmic microwave background on their way to us?Energy spectrum; GZK cutoff; Atmospheric fluorescence1998
261 Dawson, KyleSubaru FOCAS spectroscopic observations of high-redshift supernovaeWe present spectra of high-redshift supernovae (SNe) that were taken with the Subaru low-resolution optical spectrograph, FOCAS. These SNe were found in SN surveys with Suprime-Cam on Subaru, the CFH12k camera on the Canada-France-Hawaii Telescope, and the Advanced Camera for Surveys on the Hubble S...2010-01-01
262 Vardeny, Zeev ValentineRaman-scattering study of pressure-induced phase transitions in CuIThe pressure-induced phase transitions: zinc-blende (ZB) --* rhombohedral -> tetragonal in Cul were studied by Raman scattering. The rhombohedral primitive cell is presented as a slightly distorted ZB unit cell that is twice as long as the primitive cell in the [111] direction. By folding back the Z...Raman-scattering; Pressure cell; Phase transitions1977-01
263 Boehme, ChristophSpin-dependent processes at the crystalline Si-SiO2 interface at high magnetic fieldsAn experimental study on the nature of spin-dependent excess charge-carrier transitions at the interface between (111)-oriented phosphorous-doped ([P]) ~ 1015 cm−3) crystalline silicon and silicon dioxide at high magnetic field (B0~8.5 T) is presented. Electrically detected magnetic-resonance (E...Silicon interfaces; Spin-dependent recombination2008-07
264 Hultine, KevinEcohydrologic significance of hydraulic redistribution in a semiarid savannaRecent studies have illuminated the process of hydraulic redistribution, defined as the translocation of soil moisture via plant root systems, but the long-term ecohydrologic significance of this process is poorly understood. Copyright [year] American Geophysical Union. Reproduced by permission...Moisture; Roots; Water2008
265 Olivera, Baldomero M.Identification of a novel pharmacophore for peptide toxins interacting with K+ channelsқM-conotoxin RIIIK blocks TSha1 K+ channels from trout with high affinity by interacting with the ion channel pore. As opposed to many other peptides targeting K+ channels, қM-RIIIK does not possess a functional dyad. In this study we combine thermodynamic mutant cycle analysis and docking calc...Conotoxins; Peptide toxins; қM-conotoxin RIIIK; Pharmacophore2005
266 Dale, ColinKinetics of maturation of trypanosome infections in tsetseEstimates of the time delay between the infective bloodmeal and maturation (incubation or maturation time) for 4 trypanosome stocks (2 Trypanozoon and 2 Trypanosoma congolense) show that maturation time in tsetse is not a parasite species-specific constant. The mean incubation time of a Trypanosoma ...1995
267 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
268 Coley, Phyllis D.; Kursar, Thomas A.Effects of weather on fungal abundance and richness among 25 communities in the Intermountain WestBecause moisture and temperature influence the growth of fungi, characterizing weather conditions favorable for fungi may be used to predict the abundance and richness of fungi in habitats with different climate conditions. To estimate habitat favorability to fungi, we examined the relationship of f...Intermountain West; Utah; Microclimate; Fungal prevalence2002
269 Armentrout, Peter B.Electron impact ionization cross section of metastable N2(A Σu+)Extensive studies of electron impact cross sections have been carried out both experimentally and theoretically for a number of ground state atoms and molecules.1 In general, as the electron energy is increased, such cross sections rise from a threshold at the ionization potential to a peak at an e...Ion beam; Nitrogen1981
270 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
271 Voth, Gregory Alan; Sarofim, Adel F.Identification of pathways for polyaromatic growth using molecular dynamicsReaction pathways for polyaromatic growth in combustion environments are explored theoretically using molecular dynamic techniques. The reaction systems considered include cyclization reactions that involve H atom migration. Specifically we examine the absorption of acetylene on an aromatic ring rad...2004
272 Williams, Clayton C.; Huang, YufengQuantitative two-dimensional dopant profile measurement and inverse modeling by scanning capacitance microscopyQuantitative dopant profile measurements are performed on a nanometer scale by scanning capacitance microscopy (SCM). An atomic force microscope is used to position a nanometer scale tip at a semiconductor surface, and local capacitance change is measured as a function of sample bias. A new feedback...Dopant profile; Capacitance change; Scanning capacitance microscopy; Feedback control1995
273 Miller, Joel Steven; Epstein, Arthur J.Spin frustration and metamagnetic behavior in a molecular-based quasi 1-D-ferrimagnetic chain: (MnTPP)(TCNE)We report an experimental observation of spin frustration and metamagnetic behavior in a quasi-1D ferrimagnetic chain, (MnTPP) + (TCNE) -. Metastability, hysteresis effects, and irreversibility of thermal and magnetic histories are observed in magnetization measurements. The "memory" phenomenon is ...Magnetic; Magnetization; Anisotropy1993
274 Potts, Wayne K.Emigration behavior of Clark's NutcrackerEruptive movements of the Clark's Nutcracker (Nucifraga columbiana) were observed during the late summer and fall of 1977, 1978 and 1979 in northern Utah and adjacent states. Over 2,000 emigrating nutcrackers were seen during these periods. Eruptions began in mid to late August, about the time nutcr...Breeding range; Flocks; Observations1981
275 Poulter, Charles DaleYeast squalene synthase. A mechanism for addition of substrates and activation by NADPHSqualene synthase catalyzes the condensation of two molecules of farnesyl diphosphate (FPP) to give presqualene diphosphate (PSPP) and the subsequent reductive rearrangement of PSPP to squalene. Previous studies of the mechanism of addition of FPP to the enzyme have led to conflicting interpretation...Enzyme Activation; Sesquiterpenes; Kinetics1993-04-15
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