UScholar Works
 
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CreatorTitleDescriptionSubjectDate
176 Miller, Jan D.; Deo, Milind; Lin, Chen-LuhDistribution of multiphase fluids in porous media: comparison between lattice Boltzmann modeling and micro-x-ray tomographyA parallel implementation of the three-dimensional Shan-and-Chen multicomponent, multiphase lattice Boltzmann method (LBM) was used to simulate the equilibrium distributions of two immiscible fluids in porous media. The simulations were successfully validated against cone-beam x-ray microtomographi...Multiphase fluid flow; porous media; X-ray microtomography2008-02
177 Stringfellow, Gerald B.; Zhu, Jing Yi; Liu, FengDual-surfactant effect to enhance p-type doping in III-V semiconductor thin filmsSurfactant effects are usually achieved by the addition of a single surface element. We demonstrate by first-principles calculations a dual-surfactant effect of Sb and H on enhancing Zn doping in organometallic vapor phase epitaxially grown GaP thin films. The combined effects of Sb and H lower sig...Surfactants; p-type doping2008-11
178 Goller, FranzDynamical origin of spectrally rich vocalizations in birdsongBirdsong is a model system for learned vocal behavior with remarkable parallels to human vocal development and sound production mechanisms. Upper vocal tract filtering plays an important role in human speech, and its importance has recently also been recognized in birdsong. However, the mechanisms...Taeniopygia guttata; Labial oscillations; SNILC bifurcation2008-07
179 Boehme, ChristophEffect of exchange coupling on coherently controlled spin-dependent transition ratesThe effect of exchange interactions within spin pairs on spin-dependent transport and recombination rates through localized states in semiconductors during coherent electron-spin resonant excitation is studied theoretically. It is shown that for identical spin systems, significant quantitative diff...Spin coherence; Electron spin nutations2008-06
180 Freire, Juliana; Silva, Claudio T.End-to-end eScience: integrating workflow, query, visualization, and provenance at an ocean observatoryData analysis tasks at an Ocean Observatory require integrative and and domain-specialized use of database, workflow, visualization systems. We describe a platform to support these tasks developed as part of the cyberinfrastructure at the NSF Science and Technology Center for Coastal Margin Obser...Coastal margins; Ocean observatories; Workflow systems; VisTrails2008-12
181 Mower, Allyson; Youngkin, Mary E.Expanding access to published research: open access and self-archivingThe paper describes how creators can expand access to research by publishing with open access journals and by archiving in digital repositories.Open Access; Research; Self-Archiving2008-03
182 Sokolsky, PierreFirst observation of the Greisen-Zatsepin-Kuzmin suppressionThe High Resolution Fly's Eye (HiRes) experiment has observed the Greisen-Zatsepin-Kuzmin suppression (called the GZK cutoff) with a statistical significance of five standard deviations. HiRes' measurement of the flux of ultrahigh energy cosmic rays shows a sharp suppression at an energy of 6 x 10^1...Extensive air showers; Suppression; Energy spectrum; Fluorescence; GZK cutoff2008-03
183 Liu, FengFirst-principles study of electronic properties of biaxially strained silicon: effects on charge carrier mobilityUsing first-principles method, we calculate the electronic band structure of biaxially strained silicon, from which we analyze the change in electron and hole effective mass as a function of strain and determine the mobility of electrons and holes in the biaxially strained silicon based on Boltzmann...Biaxially strained silicon; Boltzmann transport theory2008-12
184 Hansen, Charles D.Flow charts: visualization of vector fields on arbitrary surfacesWe introduce a novel flow visualization method called Flow Charts, which uses a texture atlas approach for the visualization of flows defined over curved surfaces. In this scheme, the surface and its associated flow are segmented into overlapping patches, which are then parameterized and packed in ...2008-09
185 Saam, Brian; Pugmire, Ronald J.Gas-phase spin relaxation of 129XeWe have completed an extensive study of 129Xe longitudinal spin relaxation in the gas phase, involving both intrinsic and extrinsic mechanisms. The dominant intrinsic relaxation is mediated by the formation of persistent Xe2 van der Waals dimers. The dependence of this relaxation on applied magnetic...129Xe; Gas-phase spin relaxation2008-10
186 Werner, Carol M.; Sansone, Carol; Brown, Barbara B.Guided group discussion and attitude change: the roles of normative and informational influenceGroup discussion has effectively changed attitudes and behaviors compared to individually-targeted messages (Lewin, 1952; Werner, 2003). This study examines the roles of normative and informational social influence in this effect. High school students heard a message about replacing toxic products w...Elaboration likelihood model; ELM; waste reduction; sustainability; household hazardous waste; HHW; toxic waste; nontoxic alternatives; group discussion2008-03
187 Harrison, Reid R.HermesC: RF wireless low-power neural recording for freely behaving primatesNeural prosthetics for motor systems is a rapidly growing field with the potential to provide treatment for amputees or patients suffering from neurological injury and disease. To determine whether a physically active patient such as an amputee can take advantage of these systems, we seek to devel...HermesC; RF wireless; Low-power; Neural recording; Neural prosthetics; Integrated Neural Interface; Macaques2008-05
188 Wu, Yong-ShiHigh-precision quasienergies for a driven two-level atom at the two-photon preresonanceA computation with unprecedented precision is presented for quasienergies of a two-level atom in a monochromatic radiation on the basis of a recently obtained exact expression [D.-S. Guo et al., Phys. Rev. A 73,023419 (2006)]. We start with the proof of an expression theorem. With this theorem the ...Quasienergies; Preresonance; Floquet periodicity2008-02
189 Wei, Y. H. DennisInstitutions, location, and network of multinational enterprises in China: a case study of HangzhouBased on extensive interviews with local government officials and a survey of forty-four foreign-invested enterprises, this paper examines the role of local formal institutions and their constituent components in intra-urban location decisions of multinational enterprises (MNEs) and in network pro...Institutions; Multinational enterprises; Foreign investment; Hangzhou, China2008-01
190 Maloney, Thomas N.Living standards in black and white: evidence from the heights of Ohio prison inmates, 1829-1913The use of height data to measure living standards is now a well-established method in the economic history literature. Moreover, a number of core findings are widely agreed upon. There are still some populations, places, and times, however, for which anthropometric evidence remains limited. One su...Stature, Inequality, Nineteenth century US race relations2008-07
191 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
192 Miller, Joel Steven; Epstein, Arthur J.Magnetic bistability and nucleation of magnetic bubbles in a layered 2D organic-based magnet [Fe(TCNE)(NCMe)2][FeC14]The 2D layered organic-based magnet [Fe(TCNE)(NCMe)2][FeCl4] (TCNE ¼ tetracyanoethylene) exhibits a unique macroscopic magnetic bistability between the field-cooled and zero-field-cooled states, which cannot be explained by either superparamagnetic behavior or spin freezing due to spin glass orde...Organic-based magnets; Tetracyanoethylene; Magnetic bistability; Nucleation2008-11
193 Vardeny, Zeev ValentineMagnetic field effects in ∏-conjugated polymer-fullerene blends: evidence for multiple componentsWe studied magnetoconductance (MC) and magnetoelectroluminescence (MEL) in organic diodes from blends of ∏-conjugated polymers and fullerenes at various concentrations, c. The MC response is composed of several components that depend on the applied bias voltage and c. A dominant positive low-field...pi-conjugated polymers; Fullerene blends; Magnetic field effects; Magnetoconductance; Magnetoelectroluminescence; MC; MEL; Organic magnetoresistance; OMAR; Organic diodes2008-12
194 Furse, Cynthia M.MIMO transmission equationMultiple-input, multiple-output (MIMO) antenna systems such as the one depicted in Fig. 1 offer capacity benefits over their single-input, single-output (SISO) counterparts [1], thus attracting considerable current research. MIMO performance depends on a wide range of parameters [1] including radia...2008-07
195 Gerton, JordanNanoscale fluorescence microscopy using carbon nanotubesWe demonstrate the use of single-walled carbon nanotubes as nano-optical probes in apertureless near-field fluorescence microscopy. The carbon nanotubes strongly quench fluorescence leading to near-field contrast with spatial resolution of ~20 nm.2008-07
196 Sokolsky, PierreObservation of the suppression of the flux of cosmic rays above 4×10^19eVThe energy spectrum of cosmic rays above 2.5 x 10^18 eV, derived from 20 000 events recorded at the Pierre Auger Observatory, is described. The spectral index γ of the particle flux, J∞ E-γ, at energies between 4 x 10^18 eV and 4 x 10^19 eV is 2.69 ± 0.02(stat) ± 0.06(syst), steepening to 4.2 ...Extensive air showers; Energy spectrum; Fluorescence; Suppression2008-08
197 Saam, BrianOptically polarized 129Xe NMR investigation of carbon nanotubesWe demonstrate the utility of optically polarized 129Xe NMR in a convection cell for measuring the surface properties of materials. In particular, we show adsorption of xenon gas on oxidatively purified single- and multiwalled carbon nanotubes. The interaction between xenon and multiwalled nanotube...Carbon nanotubes; Multiwalled nanotubes; 129Xe NMR; Gas adsorption2008-12
198 Vardeny, Zeev ValentinePolarization memory decay spectroscopy of photoexcitations in ∏-conjugated polymers: evidence for excimersWe used the technique of ultrafast transient polarized photomodulation in the visible/near-infrared range and polarization memory decay (PMD) spectroscopy to study the primary photoexcitations in films and solutions of two poly(phenylene-vinylene) (PPV) derivatives, namely, 2-methoxy-5-(2'-ethylhex...Photoexcitations; pi-conjugated polymers; Polarization memory decay spectroscopy; PMD; DOO-PPV; MEH-PPV; Ultrafast transient polarized photomodulation; Intrachain singlet excitons; Excimers; Interchain charge transfer exciton2008-05
199 Parker, Steven G.Practical global illumination for interactive particle visualizationParticle-based simulation methods are used to model a wide range of complex phenomena and to solve time-dependent problems of various scales. Effective visualizations of the resulting state will communicate subtle changes in the three-dimensional structure, spatial organization, and qualitative tren...Interactive particle visualization; Global illumination; Ray tracing; Luminance textures2008-02
200 Furse, Cynthia M.Predicted MIMO performance in intra-vehicle channelsWireless sensor networks inside vehicles face particularly harsh multipath and shadowing constraints. The closed or semi-closed metallic structure functions much like a reverberation chamber, but with some regions shielded from other regions. Vehicles (particularly aircraft) often have extremely hig...2008-07
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