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The groundwater-land-surface-atmosphere connection: soil moisture effects on the atmospheric boundary layer in fully-coupled simulations

Description: This study combines a variably-saturated groundwater flow model and a mesoscale atmospheric model to examine the effects of soil moisture heterogeneity on atmospheric boundary layer processes. This parallel, integrated model can represent spatial variations in land-surface forcing driven by three-dimensional (3D) atmospheric and subsurface components. The development of atmospheric flow is studied in a series of idealized test cases with different initial soil moisture distributions generated b… more
Date: February 2, 2007
Creator: Maxwell, R M; Chow, F K & Kollet, S J
Partner: UNT Libraries Government Documents Department
open access

Elastic and transport properties in polycrystals of crackedgrains: Cross-property relations and microstructure

Description: Some arguments of Bristow (1960) concerning the effects of cracks on elastic and transport (i.e., electrical or thermal conduction) properties of cold-worked metals are reexamined. The discussion is posed in terms of a modern understanding of bounds and estimates for physical properties of polycrystals--in contrast to Bristow's approach using simple mixture theory. One type of specialized result emphasized here is the cross-property estimates and bounds that can be obtained using the methods pr… more
Date: October 2, 2007
Creator: Berryman, J.G.
Partner: UNT Libraries Government Documents Department
open access

Verifying the Cosmological Utility of Type Ia Supernovae:Implications of a Dispersion in the Ultraviolet Spectra

Description: We analyze the mean rest-frame ultraviolet (UV) spectrum ofType Ia Supernovae(SNe) and its dispersion using high signal-to-noiseKeck-I/LRIS-B spectroscopyfor a sample of 36 events at intermediateredshift (z=0.5) discoveredby the Canada-France-Hawaii TelescopeSupernova Legacy Survey (SNLS). Weintroduce a new method for removinghost galaxy contamination in our spectra,exploiting the comprehensivephotometric coverage of the SNLS SNe and theirhost galaxies, therebyproviding the first quantitative v… more
Date: November 2, 2007
Creator: Ellis, R. S.; Sullivan, M.; Nugent, P. E.; Howell, D. A.; Gal-Yam, A.; Astier, P. et al.
Partner: UNT Libraries Government Documents Department
open access

A Multigroup diffusion Solver Using Pseudo Transient Continuation for a Radiaiton-Hydrodynamic Code with Patch-Based AMR

Description: We present a scheme to solve the nonlinear multigroup radiation diffusion (MGD) equations. The method is incorporated into a massively parallel, multidimensional, Eulerian radiation-hydrodynamic code with adaptive mesh refinement (AMR). The patch-based AMR algorithm refines in both space and time creating a hierarchy of levels, coarsest to finest. The physics modules are time-advanced using operator splitting. On each level, separate 'level-solve' packages advance the modules. Our multigroup le… more
Date: March 2, 2007
Creator: Shestakov, A I & Offner, S R
Partner: UNT Libraries Government Documents Department
open access

Physics Design of the National High-Power Advanced Torus eXperiment

Description: Moving beyond ITER toward a demonstration power reactor (Demo) will require the integration of stable high fusion gain in steady-state, advanced methods for dissipating very high divertor heat-fluxes, and adherence to strict limits on in-vessel tritium retention. While ITER will clearly address the issue of high fusion gain, and new and planned long-pulse experiments (EAST, JT60-SA, KSTAR, SST-1) will collectively address stable steady-state high-performance operation, none of these devices wil… more
Date: July 2, 2007
Creator: Menard, J; Goldston, R; Fu, G; Gorelenkov, N; Kaye, S; Kramer, G et al.
Partner: UNT Libraries Government Documents Department
open access

Structure-based inference of molecular functions of proteins of unknown function from Berkeley Structural Genomics Center

Description: Advances in sequence genomics have resulted in an accumulation of a huge number of protein sequences derived from genome sequences. However, the functions of a large portion of them cannot be inferred based on the current methods of sequence homology detection to proteins of known functions. Three-dimensional structure can have an important impact in providing inference of molecular function (physical and chemical function) of a protein of unknown function. Structural genomics centers worldwide… more
Date: September 2, 2007
Creator: Kim, Sung-Hou; Shin, Dong Hae; Hou, Jingtong; Chandonia, John-Marc; Das, Debanu; Choi, In-Geol et al.
Partner: UNT Libraries Government Documents Department
open access

Pushing the limits of plasma length in inertial fusion laser-plasma interaction experiments

Description: We demonstrate laser beam propagation and low backscatter in laser produced hohlraum plasmas of ignition plasma length. At intensities I < 5 x 10{sup 14} W cm{sup -2} greater than 80% of the energy in a blue (3{omega}, 351 nm) laser is transmitted through a L=5-mm long, high-temperature (T{sub e} = 2.5 keV), high-density (n{sub e} = 5 x 10{sup 20} cm{sup -3}) plasma. These experiments show that the backscatter scales exponentially with plasma length which is consistent with linear theory. Th… more
Date: August 2, 2007
Creator: Froula, D; Divol, L; London, R; Michel, P; Berger, R L; Meezan, N et al.
Partner: UNT Libraries Government Documents Department
open access

Lithium Insertion Chemistry of Some Iron Vanadates

Description: Lithium insertion into various iron vanadates has been investigated. Fe{sub 2}V{sub 4}O{sub 13} and Fe{sub 4}(V{sub 2}O{sub 7}){sub 3} {center_dot} 3H{sub 2}O have discharge capacities approaching 200 mAh/g above 2.0 V vs. Li{sup +}/Li. Although the potential profiles change significantly between the first and subsequent discharges, capacity retention is unexpectedly good. Other phases, structurally related to FeVO{sub 4}, containing copper and/or sodium ions were also studied. One of these, {b… more
Date: February 2, 2007
Creator: Patoux, Sebastien & Richardson, Thomas J.
Partner: UNT Libraries Government Documents Department
open access

Global polarization measurement in Au+Au collisions

Description: The system created in non-central relativisticnucleus-nucleus collisions possesses large orbital angular momentum. Dueto spin-orbit coupling, particles produced in such a system could becomeglobally polarized along the direction of the system angular momentum. Wepresent the results of Lambda and anti-Lambda hyperon global polarizationmeasurements in Au+Au collisions at sqrt sNN=62.4 GeV and 200 GeVperformed with the STAR detector at RHIC. The observed globalpolarization of Lambda and anti-Lambd… more
Date: August 2, 2007
Creator: Abelev, B. I.; Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Galvanic interpretation of self-potential signals associated withmicrobial sulfate-reduction

Description: We have evaluated the usefulness of the self-potential (SP)geophysical method to track the onset and location of microbialsulfate-reduction in saturated sediments during organic carbon amendment.Following stimulation of sulfate-reducing bacteria (SRB) by addition oflactate, anomalous voltages exceeding 600 mV correlated in space and timewith the accumulation of dissolved sulfide. Abiotic experiments in whichthe sulfide concentration at the measurement electrode was systematicallyvaried showed a… more
Date: May 2, 2007
Creator: Williams, Kenneth H.; Hubbard, Susan S. & Banfield, Jillian F.
Partner: UNT Libraries Government Documents Department
open access

Measurement of Transverse Single-Spin Asymmetries for Di-JetProduction in Proton-Proton Collisions at sqrt s = 200 GeV

Description: We report the first measurement of the opening angledistribution between pairs of jets produced in high-energy collisions oftransversely polarized protons. The measurement probes (Sivers)correlations between the transverse spin orientation of a proton and thetransverse momentum directions of its partons. With both beams polarized,the wide pseudorapidity (-1 leq eta leq +2) coverage for jets permitsseparation of Sivers functions for the valence and sea regions. Theresulting asymmetries are all c… more
Date: October 2, 2007
Creator: Abelev, B. I.; Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Status of the International Muon Ionization Cooling Experiment (MICE)

Description: An international experiment to demonstrate muonionization cooling is scheduled for beam at RutherfordAppleton Laboratory (RAL) in 2007. The experimentcomprises one cell of the Study II cooling channel [1],along with upstream and downstream detectors to identifyindividual muons and measure their initial and final 6Dphase-space parameters to a precision of 0.1percent. Magneticdesign of the beam line and cooling channel are completeand portions are under construction. The experiment willbe describ… more
Date: February 2, 2007
Creator: Zisman, Michael S. & Zisman, Michael S.
Partner: UNT Libraries Government Documents Department
open access

Effect of rogue particles on the sub-surface damage of fused silica during grinding/polishing

Description: The distribution and characteristics of surface cracks (i.e., sub-surface damage or scratching) on fused silica formed during grinding/polishing resulting from the addition of rogue particles in the base slurry has been investigated. Fused silica samples (10 cm diameter x 1 cm thick) were: (1) ground by loose abrasive grinding (alumina particles 9-30 {micro}m) on a glass lap with the addition of larger alumina particles at various concentrations with mean sizes ranging from 15-30 {micro}m, or (… more
Date: May 2, 2007
Creator: Suratwala, T I; Steele, R; Feit, M D; Wong, L; Miller, P E; Menapace, J A et al.
Partner: UNT Libraries Government Documents Department
open access

Comparison of amplified spontaneous emission pulse cleaners for use in chirped pulse amplification front end lasers

Description: We compare various schemes for removing amplified spontaneous emission from seed laser pulses. We focus on compact schemes that are compatible with fiber laser front end systems with pulse energies in the 10nJ-1{micro}J range and pulse widths in the 100fs-10ps range. Pre-pulse contrast ratios greater than 10{sup 9} have been measured.
Date: July 2, 2007
Creator: Dawson, J.; Siders, C.; Phan, H.; Kanz, V. & Barty, C.
Partner: UNT Libraries Government Documents Department
open access

Telomere dysfunction and cell survival: Roles for distinct TIN2-containing complexes

Description: Telomeres are maintained by three DNA binding proteins (TRF1, TRF2 and POT1), and several associated factors. One factor, TIN2, binds TRF1 and TRF2 directly and POT1 indirectly. Along with two other proteins, TPP1 and hRap1, these form a soluble complex that may be the core telomere maintenance complex. It is not clear whether sub-complexes also exist in vivo. We provide evidence for two TIN2 sub-complexes with distinct functions in human cells. We isolated these two TIN2 sub-complexes from nuc… more
Date: October 2, 2007
Creator: Kim, Sahn-ho; Davalos, Albert R.; Heo, Seok-Jin; Rodier, Francis; Zou, Ying; Beausejour, Christian et al.
Partner: UNT Libraries Government Documents Department
open access

Fabry-Perot / PDV Comparison

Description: Measures the fast pulses seen with exploding bridge flyers by PDV
Date: May 2, 2007
Creator: Hodgin, Ralph; May, Chadd; Hanks, Roy; Hansen, Don; Whitworth, Tony & Strand, Ted
Partner: UNT Libraries Government Documents Department
open access

Compton scattering measurements from dense plasmas

Description: Compton scattering has been developed for accurate measurements of densities and temperatures in dense plasmas. One future challenge is the application of this technique to characterize compressed matter on the National Ignition Facility where hydrogen and beryllium will approach extremely dense states of matter of up to 1000 g/cc. In this regime, the density, compressibility, and capsule fuel adiabat may be directly measured from the Compton scattered spectrum of a high-energy x-ray line sourc… more
Date: October 2, 2007
Creator: Glenzer, S. H.; Neumayer, P.; Doeppner, T.; Landen, L.; Lee, R. W.; Wallace, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Diffusion-controlled spherulite growth in obsidian inferred from H2O concentration profiles

Description: Spherulites are spherical clusters of radiating crystals that occur naturally in rhyolitic obsidian. The growth of spherulites requires diffusion and uptake of crystal forming components from the host rhyolite melt or glass, and rejection of non-crystal forming components from the crystallizing region. Water concentration profiles measured by synchrotron-source Fourier transform spectroscopy reveal that water is expelled into the surrounding matrix during spherulite growth, and that it diffuses… more
Date: November 2, 2007
Creator: Watkins, Jim; Watkins, Jim; Manga, Michael; Huber, Christian & Martin, Michael C.
Partner: UNT Libraries Government Documents Department
open access

A Quasicontinuum Study of Nanovoid Collapse under Uniaxial Loading in Ta

Description: The mechanisms underlying the deformation of nanovoids in Ta single crystals are analyzed when they are subjected to cyclic uniaxial deformation using numerical simulations. Boundary and cell-size effects have been mitigated by means of the Quasicontinuum (QC) method. We have considered {approx} 1 billion-atom systems containing 10.9 nm voids. Two kinds of simulations have been performed, each characterized by a different boundary condition. First, we compress the material along the nominal [0 … more
Date: December 2, 2007
Creator: Marian, J.; Knap, J. & Campbell, G.
Partner: UNT Libraries Government Documents Department
open access

Self-Consistent 3D Modeling of Electron Cloud Dynamics and Beam Response

Description: We present recent advances in the modeling of beam electron-cloud dynamics, including surface effects such as secondary electron emission, gas desorption, etc, and volumetric effects such as ionization of residual gas and charge-exchange reactions. Simulations for the HCX facility with the code WARP/POSINST will be described and their validity demonstrated by benchmarks against measurements. The code models a wide range of physical processes and uses a number of novel techniques, including a la… more
Date: April 2, 2007
Creator: Furman, Miguel; Furman, M. A.; Celata, C. M.; Kireeff-Covo, M.; Sonnad, K. G.; Vay, J. L. et al.
Partner: UNT Libraries Government Documents Department
open access

10-kJ Status and 100-kJ Future for NIF PetaWatt Technology

Description: We discuss the status of the NIF ARC, an 8-beam 10-kJ class high-energy petawatt laser, and the future upgrade path of this and similar systems to 100-kJ-class with coherent phasing of multiple apertures.
Date: July 2, 2007
Creator: Siders, C W; Crane, J K; Rushford, M C; Haefner, L C; Hernandez, J E; Dawson, J W et al.
Partner: UNT Libraries Government Documents Department
open access

An X-ray Study of Shock-Recovered Tantalum Single Crystals

Description: In this paper, we report shock-induced new grains and residual lattice tension in tantalum single crystals. The single crystals with orientations in [001], [011], [111], and [123] directions are shocked at {approx}55 GPa in gas gun under almost identical conditions. New grains in the shocked crystals are revealed by x-ray scanning analysis. Rather than lattice compression that is frequently probed by in situ x-ray diffraction technique, we find significant residual lattice tension in the recove… more
Date: August 2, 2007
Creator: Zhou, J; Hsiung, L L; Chau, R & Saw, C K
Partner: UNT Libraries Government Documents Department
open access

How to Find More Supernovae with Less Work: Object ClassificationTechniques for Difference Imaging

Description: We present the results of applying new object classificationtechniques to difference images in the context of the Nearby SupernovaFactory supernova search. Most current supernova searches subtractreference images from new images, identify objects in these differenceimages, and apply simple threshold cuts on parameters such as statisticalsignificance, shape, and motionto reject objects such as cosmic rays,asteroids, and subtraction artifacts. Although most static objectssubtract cleanly, even a … more
Date: May 2, 2007
Creator: Bailey, Stephen; Aragon, Cecilia; Romano, Raquel; Thomas, RollinC.; Weaver, Benjamin A. & Wong, Daniel
Partner: UNT Libraries Government Documents Department
open access

The Genetically Remote Pathogenic Strain NVH391-98 of the Bacillus cereus Group Represents the Cluster of Thermophilic Strains

Description: Bacteria of the Bacillus cereus group are known to cause food poisoning. A rare phylogenetically remote strain, NVH391-98, was recently characterized to encode a particularly efficient cytotoxin K presumably responsible for food poisoning. This pathogenic strain and its close relatives can be phenotypically distinguished from other strains of the B. cereus group by the inability to grow at temperatures below 17 degrees C and by the ability to grow at temperatures from 48 to 53 degrees C. A temp… more
Date: October 2, 2007
Creator: Auger, Sandrine; Galleron, Nathalie; Bidnenko, Elena; Ehrlich, S. Dusko; Lapidus, Alla & Sorokin, Alexei
Partner: UNT Libraries Government Documents Department
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