UScholar Works
 
Filters: School Or College: "College of Science" Collection: "ir_uspace"
1 - 25 of 36
Number of results to display per page
CreatorTitleDescriptionSubjectDate
1 Miller, Joel Steven[MeNC5H5]2[TCNE]2 (TCNE = tetracyanoethylene). Single crystal X-ray and neutron diffraction characterization of an exceptionally long 2.8 Å C-C bondThe reaction of N-methylpyridinium iodide, Mepy+I-, and tetracyanoethylene (TCNE) forms [Mepy]2[TCNE]2, which possesses [TCNE]2 2' with an intradimer C-C bond distance of 2.806(1)Å at 50 K from X-ray diffraction, and 2.801(4)Å at 50 K from neutron diffraction. In the IR it exhibits nChN absorption...C-C bond; Tetracyanoethylene; Neutron diffraction; X-ray diffraction; Multicenter C-C bonding2009
2 Beckerle, Mary C.ALP-enigma protein ALP-1 functions in actin filament organization to promote muscle structural integrity in Caenorhabditis elegansMutations that affect the Z-disk-associated ALP-Enigma proteins have been linked to human muscular and cardiac diseases. Despite their clear physiological significance for human health, the mechanism of action of ALP-Enigma proteins is largely unknown. In Caenorhabditis elegans, the ALP-Enigma prot...Actin; Caenorhabditis elegans; Contractility; alp-1 mutants; Z-disks; Kettin2009
3 Golden, Kenneth M.Climate change and the mathematics of transport in sea iceAs the boundary layer between the ocean and atmosphere in the polar regions, sea ice is a critical component of the global climate system. As temperatures on Earth have warmed, the Arctic sea ice pack in particular has exhibited a dramatic decline in its summer extent. Indeed, the polar sea-ice pack...Polar ice; Fluid flow; Complex permittivity2009
4 Gondolo, PaoloDark stars: BegynnelsenThe first phase of stellar evolution in the history of the universe may be Dark Stars, powered by dark matter heating rather than by fusion. Weakly interacting massive particles, which are their own antiparticles, can annihilate and provide an important heat source for the first stars in the univers...Dark stars; WIMP; Weakly interacting massive particles; Annihilations2009
5 Gondolo, PaoloDark Stars: Död och ÅteruppståndelseThe first phase of stellar evolution in the history of the universe may be Dark Stars, powered by dark matter heating rather than by fusion. Weakly interacting massive particles, which are their own antiparticles, can annihilate and provide an important heat source for the first stars in the univers...Dark stars; WIMP; Weakly interacting massive particles2009
6 Gondolo, PaoloDark Stars: the first stars in the universe may be powered by dark matter healingA new line of research on Dark Stars is reviewed, which suggests that the first stars to exist in the universe were powered by dark matter heating rather than by fusion. Weakly Interacting Massive Particles, which may be there own antipartmers, collect inside the first stars and annihilate to produc...Dark stars; WIMP; Weakly interacting massive particles2009
7 Lupton, John MarkEnergetic disorder limits energy transfer in semiconductor nanocrystal-DNA-dye conjugatesWe demonstrate the influence of spectral linewidths of individual donor-acceptor couples on energy transfer efficiency in semiconductor nanocrystal-DNA-organic dye conjugates. Temperature-dependent single molecule and ensemble spectroscopy data are analyzed using the Förster theory within the mac...2009
8 Armentrout, Peter B.Methane activation by cobalt cluster cations, Con+ (n=2-16): reaction mechanisms and thermochemistry of cluster-CHx (x=0-3) complexesThe kinetic energy dependences of the reactions of Con + (n=2-16) with CD4 are studied in a guided ion beam tandem mass spectrometer over the energy range of 0-10 eV. The main products are hydride formation, ConD+, dehydrogenation to form ConCD2 +, and double dehydrogenation yielding ConC+.Cobalt ions; Transition metal ions; Bond energies; Endothermic reactions; Dehydrogenation; Deuterated methane2009
9 Coley, Phyllis D.; Kursar, Thomas A.Pests vs. drought as determinants of plant distribution along a tropical rainfall gradientUnderstanding the mechanisms that shape the distribution of organisms can help explain patterns of local and regional biodiversity and predict the susceptibility of communities to environmental change. In the species-rich tropics, a gradient in rainfall between wet evergreen and dry seasonal forests...Drought tolerance; Herbivory; Panama; Pathogen attack; Rainfall gradient; Tree distribution; Tropical forests2009
10 Vardeny, Zeev Valentine; Nahata, AjayTHz anomalous transmission in plasmonic lattices; incidence angle dependenceThe phenomenon of anomalous transmission through subwavelength aperture arrays in metallic films (plasmonic lattices) is thought to be mediated by surface plasmon polaritons (SPP) on the film surfaces. Using terahertz time-domain spectroscopy we systematically studied the anomalous transmission spec...THz anomalous transmission; Plasmonic lattices; Incidence angle dependence; THz radiation; Light polarization; Effective dielectric response; Notch filter2009
11 DeTar, CarletonB̄→D*ℓν̄ form factor at zero recoil from three-flavor lattice QCD: a model independent determination of [Vcb]We present the first lattice QCD calculation of the form factor for B→ D* lv with three flavors of sea quarks. We use an improved staggered action for the light valence and sea quarks (the MILC configurations), and the Fermilab action for the heavy quarks. The form factor is computed at zero recoi...Staggered quarks2009-01
12 DeTar, CarletonB→πlν semileptonic form factor from three-flavor lattice QCD: a model-independent determination of [Vub]We calculate the form factor f+(q2) for B-meson semileptonic decay in unquenched lattice QCD with 2 + 1 flavors of light sea quarks. We use Asqtad-improved staggered light quarks and a Fermilab bottom quark on gauge configurations generated by the MILC Collaboration. We simulate with several light...Semileptonic decay2009-03
13 Gondolo, PaoloDark matter axions revisitedWe study for what specific values of the theoretical parameters the axion can form the totality of cold dark matter. We examine the allowed axion parameter region in the light of recent data collected by the WMAP5 mission plus baryon acoustic oscillations and supernovae, and assume an inflationary...WMAP5 mission; PQ symmetry; Anharmonicity; Misalignment angle2009-08
14 Gondolo, PaoloDark matter in the MSSM golden regionDark matter is examined within the ‘‘golden region'' of the minimal supersymmetric standard model. This region satisfies experimental constraints, including a lower bound on the Higgs mass of 114 GeV, and minimizes fine-tuning of the Z boson mass. Here we impose additional constraints (particula...MSSM golden region; Neutralinos; Higgs mass2009-02
15 Miller, Joel Steven; Epstein, Arthur J.Direct evidence of electron spin polarization from an organic-based magnet: [FeII(TCNE)(NCMe)2][FeIII Cl4]Direct evidence of an organic-based magnet with a finite electron spin polarization at the Fermi edge is shown from spin-resolved photoemission of the [FeII(TCNE)(NCMe)2][FeIIICl4] organic-based magnet. The 23% majority-based spin polarization at the Fermi edge is observed at 80 K in zero applied fi...Organic-based magnets; Electron spin polarization2009-05
16 DeTar, CarletonEquation of state and QCD transition at finite temperatureWe calculate the equation of state in 2 + 1 flavor QCD at finite temperature with physical strange quark mass and almost physical light quark masses using lattices with temporal extent Nr = 8. Calculations have been performed with two different improved staggered fermion actions, the asqtad and p4 a...Deconfinement; Chiral symmetry; Staggered fermions; Phase transitions; Polyakov loop2009-07
17 Boehme, ChristophExperimental discrimination of geminate and non-geminate recombination in a-Si:HA study of charge-carrier recombination in intrinsic hydrogenated amorphous silicon (a-Si:H) is presented using pulsed electrically and pulsed optically detected magnetic-resonance spectroscopies in order to measure the influence of spin-dependent recombination on photoluminescence (PL) and photoc...Geminate recombination2009-05
18 Boehme, ChristophFast nuclear spin hyperpolarization of phosphorus in siliconWe experimentally demonstrate a method for obtaining nuclear spin hyperpolarization, that is, polarization significantly in excess of that expected at thermal equilibrium. By exploiting a nonequilibrium Overhauser process, driven by white light irradiation, we obtain more than 68% negative nuclear p...Hyperpolarization; Spin coherence; Electrical readout2009-01
19 Shapiro, Michael D.Genetic architecture of skeletal convergence and sex determination in ninespine sticklebacksThe history of life offers plentiful examples of convergent evolution, the independent derivation of similar phenotypes in distinct lineages [1]. Convergent phenotypes among closely related lineages (frequently termed "parallel" evolution) are often assumed to result from changes in similar genes or...Convergent evolution; Skeletal convergence; Pungitius pungitius; Gasterosteus aculeatus; Comparative genetics2009-07
20 Boehme, ChristophInfluence of disorder on electrically and optically detected electron spin nutationA numerical study of the influence of disorder in semiconductors on spin-Rabi nutation observed with pulsed electrically or optically detected magnetic-resonance techniques (pEDMR and pODMR, respectively ) is presented. It is shown that transient nutation signals of disordered spin ensembles differ ...Electron spin nutations2009-02
21 Lupton, John MarkIntermittency in second-harmonic radiation from plasmonic hot spots on rough silver filmsSurface enhancement of electromagnetic fields in plasmonic hot spots formed on rough silver films enables the observation of second-harmonic generation (SHG) from single metal nanoparticles. Nonlinear light scattering from these particles exhibits blinking in analogy to luminescence from single qu...Harmonic radiation; Plasmonic hot spots; Second harmonic generation; SHG2009-10
22 Goller, FranzLow-dimensional dynamical model for the diversity of pressure patterns used in canary songDuring song production, oscine birds produce large air sac pressure pulses. During those pulses, energy is transferred to labia located at the juncture between the bronchii and the trachea, inducing the high frequency labial oscillations which are responsible for airflow modulations, i.e., the utt...Serinus canarias; Air sac pressure2009-04
23 Sokolsky, PierreMeasurement of the flux of ultra high energy cosmic rays by the stereo techniqueThe High Resolution Fly's Eye (HiRes) experiment has measured the flux of ultrahigh energy cosmic rays using the stereoscopic air fluorescence technique. The HiRes experiment consists of two detectors that observe cosmic ray showers via the fluorescence light they emit. HiRes data can be analyzed i...Ultrahigh energy cosmic rays; Fluorescence; Energy spectrum; GZK cutoff2009-08
24 Mishchenko, EugeneMesoscopic spin-Hall effect in 2D electron systems with smooth boundariesThe spin-Hall effect in a ballistic 2D electron gas with Rashba-type spin-orbit coupling and smooth edge confinement is studied. We predict that the interplay of semiclassical electron motion and quantum dynamics of spins leads to several distinct features in spin density along the edge that origina...Spin- Hall effect; 2D electron systems2009-05
25 Dawson, KyleMulti-wavelength study of XMMU J2235.3-2557: the most massive galaxy cluster at z > 1The galaxy cluster XMMU J2235.3−2557 (hereafter XMM2235), spectroscopically confirmed at z = 1.39, is one of the most distant X-ray selected galaxy clusters. It has been at the center of a multi-wavelength observing campaign with ground and space facilities. Aims. We characterize the galaxy popula...XMMU J2235.3-2557; XMM2235; X-rays; Redshift2009-12
1 - 25 of 36