UScholar Works
 
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CreatorTitleDescriptionSubjectDate
151 Boll, Steven F.Noise suppression methods for robust speech processing (1 Oct. 1976 - 31 March 1977)To develop robust speech processes, based upon the integration of digital noise suppression methods and narrow band speech analysis-synthesis methods, capable of realizing practical, real time methods for effectively processing speech recorded in practical operating environments.Digital noise suppression1977
152 Miller, Joel Steven; Epstein, Arthur J.Noise in highly correlated commensurate charge transfer saltsWe present the results of a study of the frequency (f) dependent noise power for commensurate charge transer salts with strong coulomb repulsion. f-1 noise is observed with increasing currents. Excess f-1 noise is measured for samples which were chemically doped to form solitons. Frequency indepe...Noise power; Charge-transfer salts1983
153 Golden, Kenneth M.Sea ice studies in the Weddell Sea aboard USCGC Polar SeaOur purpose was to investigate several of the characteristics of Weddell Sea pack ice that may affect the relative roles of dynamics and thermodynamics of pack ice development in this region. The total pack ice production and the movement of pack ice from its source area in the Weddell Sea is part...Floes.; Salinity; Formation1980
154 Kieda, David B.Evidence for changing of cosmic ray composition between 10(17) and 10(18) eV from multicomponent measurementsThe average mass composition of cosmic rays with primary energies between 1017 and 1018 eV has been studied using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum and the ...Cosmic rays; Particle energy; Muon array2000
155 Sokolsky, PierreEvidence for changing of cosmic ray composition between 10^17 and 10^18 eV from multicomponent measurementsThe average mass composition of cosmic rays with primary energies between 1017 and 1018 eV has been studied using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum and the...Extensive air showers; Fluorescence; Energy spectrum; Muon density; Cherenkov light2000-05
156 Miller, Joel Steven; Epstein, Arthur J.Lattice- and spin-dimensionality crossovers in a linear-chain-molecule-based ferrimagnet with weak spin anisotropy[MnOEP][HCBD], a member of the metalloporphyrin family of donor-acceptor molecule-based magnets, consists of isolated ferrimagnetic chains of alternating S=2, [MnOEP], and s=1/2, [HCBD] units (OEP=octaethylporphyrinato and HCBD=hexacyanobutadiene). Analysis of the exchange pathways reveals an exchan...Magnetic; Magnetization; Interchain1997
157 Saam, BrianLow-field orientation dependence of 3He relaxation in spin-exchange cellsWe have observed a significant dependence of 3He longitudinal relaxation times in glass spin-exchange optical pumping (SEOP) cells due only to the physical orientation of the cell in a 3 mT (30 G) applied magnetic field. The cells had no previous exposure to higher fields or were thoroughly degau...Spin-exchange optical pumping; SEOP; 3He; Hyperpolarized noble gases; Longitudinal spin-relaxation; MEOP; Low-field orientation2004-02
158 Armentrout, Peter B.Cobalt carbene ion: reactions of Co+ with C2H4, cyclo-C3H6 and cyclo-C2H4OAn ion beam apparatus is employed to study the formation of the cobalt carbene ion, CoCH2+. This ion is produced in the endothermic reaction of cobalt ions with ethene and cyclopropane and in an exothermic reaction with ethylene oxide. A model is proposed to account for the dependence of experimenta...Cobalt carbine; Ion beam; Bond dissociation energy; Reaction cross section; Endothermic reactions1981
159 Miller, Joel StevenOptical properties of cesium tetracyanoquinodimethanide, Cs2(TCNQ)3Room-temperature polarized reflectance measurements have been made on cesium tetracyanoquinodimethanide, Cs2(TCNQI3, over the frequency range between the far infrared and the near ultraviolet. The optical properties of the compound were obtained by Kramers-Kronig analysis. These properties are dom...Electrons; Lattice; Molecules1981
160 Kieda, David B.Limits on the isotropic diffuse flux of ultrahigh energy gamma radiationDiffuse ultrahigh energy g radiation can arise from a variety of astrophysical sources, including the interaction of 1020 eV cosmic rays with the 2.7 K microwave background radiation or the collapse of topological defects created in the early Universe. We describe a sensitive search for diffuse g ...G rays; Ultrahigh energy; Muons; Cosmic rays1997
161 Efros, Alexei L.Sensor-based distributed control scheme for mobile robotsIn this paper we present a sensor-based distributed control scheme for mobile robots. This scheme combines centralized and decentralized control strategies. A server-client model is used to implement this scheme where the server is a process that caries out the commands to be executed, and each clie...Sensor-based; Distributed control scheme1995
162 Armentrout, Peter B.C+(2P)+H2(D2,HD)→CH+(CD+)+H(D). I. Reaction cross sections and kinetic isotope effects from threshold to 15eV c.m.Total cross sections for the reactions of carbon (1 + ) ions with isotopic molecular hydrogen (H2, D2, and HD) to form methyliumylidene (CH+ and CD+) have been measured using guided ion beam techniques. Cross sections are reported as a function of the translational energy of the reactants from th...Methyliumylidene; Endothermic reactions; Isotope effect; Threshold energy1986
163 Miller, Joel StevenNoncollinear antiferromagnetic structure of the molecule-based magnet Mn[N(CN)2]2The crystallographic and magnetic properties of the Mn[N(CN)2]2 compound have been investigated by dc magnetization, ac susceptibility, specific heat, and zero-field neutron diffraction on polycrystalline samples. The magnetic structure consists of two sublattices which are antiferromagnetically cou...Spin; Crystal; Magnetic2000
164 DeTar, CarletonLight pseudoscalar decay constants, quark masses, and low energy constants from three-flavor lattice QCDAs part of our program of lattice simulations of three-flavor QCD with improved staggered quarks, we have calculated pseudoscalar meson masses and decay constants for a range of valence quark masses and sea-quark masses on lattices with lattice spacings of about 0.125 and 0.09 fm. We fit the lattic...Staggered quarks; Chiral symmetry; Perturbation theory2004-12
165 Sperry, John S.Vulnerability to xylem cavitation and the distribution of sonoran desert vegetationWe studied 15 riparian and upland Sonoran desert species to evaluate how the limitation of xylem pressure (Vx) by cavitation corresponded with plant distribution along a moisture gradient. Riparian species were obligate riparian trees (Fraxinus velutina, Populus fremontii, and Salix gooddingii), nat...Comparative approach; species distribution; xylem conducting efficency2000
166 Vardeny, Zeev ValentineLeng et al. replyConwell, Rothberg, and Mizes (CRM) claim [1] that, as a result of chain length distribution and vibronic sidebands of electronic levels in PPV films, there is little correlation between increase of pump photon energy (Hw) and increase of electronic energy, and therefore data from excitation spectros...Chain length distribution; Vibronic sidebands; PPV films; Pump photon energy1994
167 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
168 Armentrout, Peter B.C+(2P) + H2(D2,HD)→CH+(CD+) + H(D). I. Reaction cross sections and kinetic isotope effects from threshold to 15 eV c.m.Total cross sections for the reactions of carbon (1 + ) ions with isotopic molecular hydrogen (H2, D2 , and HD) to form methyliumylidene (CH+ and C D + ) have been measured using guided ion beam techniques. Cross sections are reported as a function of the translational energy of the reactants fro...Ion-molecule reactions; Isotope effects; Translational energy; Threshold behavior; Endothermic reactions1986
169 Gesteland, Raymond F.; Krapcho, Karen J.; Talbot, Phil; Thulin, CraigCrystallization of the MS2 translational repressor alone and complexed to bromouridineThe coat protein from the MS2 bacteriophage plays a dual role by encapsidating viral RNA and also by binding RNA as a translational repressor. In order to study the isolated dimer in a conformation not influenced by capsid interactions, a mutant molecule was crystallized that is defective in capsid ...Crystallization; RNA Bacteriophage; RNA Hairpin; Translational Repressor1995
170 Vardeny, Zeev ValentinePicosecond photomodulation study of nanocrystalline hydrogenated siliconWe have extended our photomodulation studies of nc-Si:H to the picosecond time domain. We measured the decays of photoinduced reflectivity with lOOfs temporal resolution as a function of. light intensity. Comparison with the data obtained on a-Si:H and c-Si indicates that ultrafast trapping and reco...Picosecond photomodulation; Nanocrystalline silicon1990
171 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Apparent phonon side-band modes in π-conjugated systems: polymers, oligomers and crystalsThe emission spectra of many π-conjugated polymers and oligomers contain side-band replicas with apparent frequencies that do not match the Raman active mode frequencies. Using a time dependent model we show that in such many mode systems, the increased damping of the time dependent transition dipo...2005-11
172 Ailion, David CharlesEvidence for elastic disorder in the elastically ordered phase of KCNWe have obtained evidence from 1 3C NMR measurements that the CN~ ion in the elastically ordered phase of KCN is misoriented slightly with respect to the orthorhombic b axis. This misorientation varies randomly over the lattice, averaging to zero on a macroscopic scale. The misorientations are mani...Potassium cyanide; Anisotropy; Orthorhombic crystal; NMR; Nuclear magnetic resonance1981
173 Miller, Joel StevenZero field splitting, field-dependent magnetization of mixed-valent S = 3/2 Diruthenium(II,III) tetracarboxylatesThe 2 K field-dependent magnetization, M(H), of S = 3/2 [RunII/III2(OAc)4]+ was studied. [RuII/III 2(OAc)4]+ exhibits an unusually low magnetization with respect to that predicted by the classical Brillouin function. This reduced value is a consequence of the large anisotropy arising from the large ...Spin; Coupling; Expressions2004
174 Ailion, David Charles; Morris, Alan H.Quantitative assessment of pulmonary edema by nuclear magnetic resonance methodsConsiderable progress has been made in the application of nuclear magnetic resonance (NMR) imaging and nonimaging techniques to the quantitative assessment of pulmonary edema. NMR measurements offer the advantages of being noninvasive, relatively rapid, and easily repeatable. In addition, NMR imagin...Quantitative assessment1988
175 Armentrout, Peter B.Effect of kinetic and electronic energy on the reactions of Cr+ with H2, HD, and D2The reactions of atomic chromium ions with H2 , HD, and D2 are examined using guided ion beam tandem mass spectrometry. The ground electronic state (6S) is found to react inefficiently. The thresholds of these data are analyzed to yield a 0 K bond dissociation energy for CrH+ of 1.37 ± 0.09 eV (31...Chromium ions; Hydrogen; Deuteride; Bond energy1987
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