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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
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IMG/M: A data management and analysis system for metagenomes

Description: IMG/M is a data management and analysis system for microbial community genomes (metagenomes) hosted at the Joint Genome Institute (JGI). IMG/M consists of metagenome data integrated with isolate microbial genomes from the Integrated Microbial Genomes (IMG) system. IMG/M provides IMG's comparative data analysis tools extended to handle metagenome data, together with metagenome-specific analysis tools. IMG/M is available at http://img.jgi.doe.gov/m. Studies of the collective genomes (also known a… more
Date: August 1, 2007
Creator: Markowitz, Victor M.; Ivanova, Natalia N.; Szeto, Ernest; Palaniappan, Krishna; Chu, Ken; Dalevi, Daniel et al.
Partner: UNT Libraries Government Documents Department
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Initial Study Comparing the Radiating Divertor Behavior in Single-Null and Double-Null Plasmas in DIII-D

Description: 'Puff and pump' radiating divertor scenarios [1,2] were applied to upper SN and DN H-mode plasmas. Under similar operating conditions, argon (Ar) accumulated in the main plasma of single-null (SN) plasmas more rapidly and reached a higher steady-state concentration when the B x {del}B ion drift direction was toward the divertor than when the B x {del}B ion drift direction was out of the divertor. The initial rate that Ar accumulated inside double-null (DN) plasmas was more than twice that of co… more
Date: June 27, 2007
Creator: Petrie, T; Brooks, N; Fenstermacher, M; Groth, M; Hyatt, A; Isler, R et al.
Partner: UNT Libraries Government Documents Department
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LC scintillator-based muon detector tail-catcher R&D

Description: Preliminary analysis of test beam data from strip scintillator planes read-out with multi-anode PMTs (MAPMTs) is presented along with a description of the independent systematic measurements of relative response for all channels of several MAPMTs used in the tests. Test beam measurements for the response of a scintillator strip, read out with Si photo-sensors, is also described.
Date: November 1, 2007
Creator: Abrams, R.; Blazey, G.; Driutti, A.; Dychkant, A.; Fisk, H.E.; Gutierrez, A. et al.
Partner: UNT Libraries Government Documents Department
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NIF: A Path to Fusion Energy

Description: Fusion energy has long been considered a promising, clean, nearly inexhaustible source of energy. Power production by fusion micro-explosions of inertial confinement fusion (ICF) targets has been a long-term research goal since the invention of the first laser in 1960. The National Ignition Facility (NIF) is poised to take the next important step in the journey by beginning experiments researching ICF ignition. Ignition on NIF will be the culmination of over thirty years of ICF research on high… more
Date: June 1, 2007
Creator: Moses, Edward
Partner: UNT Libraries Government Documents Department
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glideinWMS - A generic pilot-based Workload Management System

Description: The Grid resources are distributed among hundreds of independent Grid sites, requiring a higher level Workload Management System (WMS) to be used efficiently. Pilot jobs have been used for this purpose by many communities, bringing increased reliability, global fair share and just in time resource matching. GlideinWMS is a WMS based on the Condor glidein concept, i.e. a regular Condor pool, with the Condor daemons (startds) being started by pilot jobs, and real jobs being vanilla, standard or M… more
Date: September 1, 2007
Creator: Sfiligoi, Igor
Partner: UNT Libraries Government Documents Department
open access

Sharp Reduction of the Secondary Electron Emission Yield from Grooved Surfaces

Description: The effect of an artificially-enhanced rough surface on the secondary electron emission yield (SEY) was investigated both theoretically and experimentally. Analytical studies on triangular and rectangular grooved surfaces show the connection between the characteristic parameters of a given geometry to the SEY reduction. The effect of a strong magnetic field is also discussed. SEY of grooved samples have been measured and the results agree with Monte-Carlo simulations.
Date: November 28, 2007
Creator: Pivi, M. T. F.; King, F. K.; Kirby, R. E.; Ruabenheimer, T. O.; Stupakov, G. & Le Pimpec, F.
Partner: UNT Libraries Government Documents Department
open access

ITER Shape Controller and Transport Simulations

Description: We currently use the CORSICA integrated modeling code for scenario studies for both the DIII-D and ITER experiments. In these simulations, free- or fixed-boundary equilibria are simultaneously converged with thermal evolution determined from transport models providing temperature and current density profiles. Using a combination of fixed boundary evolution followed by free-boundary calculation to determine the separatrix and coil currents. In the free-boundary calculation, we use the state-spac… more
Date: May 31, 2007
Creator: Casper, T A; Meyer, W H; Pearlstein, L D & Portone, A
Partner: UNT Libraries Government Documents Department
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Spatial resolution limits for synchrotron-based infrared spectromicroscopy

Description: Detailed spatial resolution tests were performed on beamline 1.4.4 at the Advanced Light Source synchrotron facility in Berkeley, CA. The high-brightness synchrotron source is coupled at this beamline to a Thermo-Electron Continumum XL infrared microscope. Two types of resolution tests in both the mid-IR (using a KBr beamsplitter and an MCT-A* detector) and in the near-IR (using a CaF2 beamsplitter and an InGaAS detector) were performed and compared to a simple diffraction-limited spot size mod… more
Date: October 15, 2007
Creator: Levenson, Erika; Lerch, Philippe & Martin, Michael C.
Partner: UNT Libraries Government Documents Department
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MULTISCALE MODELING OF POLYMER NANOCOMPOSITES

Description: Polymer Nanocomposites are an important class of nanomaterials with potential applications including but not limited to structural and cushion materials, electromagnetic and heat shields, conducting plastics, sensors, and catalysts for various chemical and bio processes. Success in most such applications hinges on molecular-level control of structure and assembly, and a deep understanding of how the overall morphology of various components and the interfaces between them affect the composite pr… more
Date: July 16, 2007
Creator: Maiti, A
Partner: UNT Libraries Government Documents Department
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GeV electron beams from cm-scale channel guided laser wakefieldaccelerator

Description: Laser-wakefield accelerators (LWFA) can produce electricfields of order 10-100 GV/m suitable for acceleration of electrons torelativistic energies. The wakefields are excited by a relativisticallyintense laser pulse propagating through a plasma and have a phasevelocity determined by the group velocity of the light pulse. Twoimportant effects that can limit the acceleration distanceand hence thenet energy gain obtained by an electron are diffraction of the drivelaser pulse and particle-wake deph… more
Date: February 20, 2007
Creator: Nakamura, K.; Nagler, B.; Toth, Cs.; Geddes, C. G. R.; Schroeder, C.; Esarey, E. et al.
Partner: UNT Libraries Government Documents Department
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TREATABILITY TEST FOR REMOVING TECHNETIUM-99 FROM 200-ZP-1 GROUNDWATER HANFORD SITE

Description: The 200-ZP-1 Groundwater Operable Unit (OU) is one of two groundwater OUs located within the 200 West groundwater aggregate area of the Hanford Site. The primary risk-driving contaminants within the 200-ZP-1 OU include carbon tetrachloride and technetium-99 (Tc-99). A pump-and-treat system for this OU was initially installed in 1995 to control the 0.002 kg/m{sup 3} (2000 {micro}g/L) contour of the carbon tetrachloride plume. Carbon tetrachloride is removed from groundwater with the assistance o… more
Date: November 29, 2007
Creator: SW, PETERSEN; AC, TORTOSO; WS, ELLIOTT & ME, BYRNES
Partner: UNT Libraries Government Documents Department
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OPTICAL AND DYNAMIC PROPERTIES OF UNDOPED AND DOPED SEMICONDUCTOR NANOSTRUCTURES

Description: This chapter provides an overview of some recent research activities on the study of optical and dynamic properties of semiconductor nanomaterials. The emphasis is on unique aspects of these properties in nanostructures as compared to bulk materials. Linear, including absorption and luminescence, and nonlinear optical as well as dynamic properties of semiconductor nanoparticles are discussed with focus on their dependence on particle size, shape, and surface characteristics. Both doped and undo… more
Date: September 28, 2007
Creator: Grant, C D & Zhang, J Z
Partner: UNT Libraries Government Documents Department
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The Formation of Contact and Very Close Binaries

Description: We explore the possibility that all close binaries, i.e. those with periods {approx}< 3 d, including contact (W UMa) binaries, are produced from initially wider binaries (periods of say 10's of days) by the action of a triple companion through the medium of Kozai Cycles with Tidal Friction (KCTF).
Date: August 10, 2007
Creator: Kisseleva-Eggleton, L & Eggleton, P P
Partner: UNT Libraries Government Documents Department
open access

Geometry of non-supersymmetric three-charge bound states

Description: We study the smooth non-supersymmetric three-charge microstatesof Jejjala, Madden, Ross and Titchener using Kaluza-Klein reductions of the solutions to five and four dimensions. Our aim is to improve our understanding of the relation between these non-supersymmetric solutions and the well-studied supersymmetric cases. We find some surprising qualitative differences. In the five-dimensional description, the solution has orbifold fixed points which break supersymmetry locally, so the geometries c… more
Date: May 14, 2007
Creator: Gimon, Eric G.; Levi, Thomas S. & Ross, Simon F.
Partner: UNT Libraries Government Documents Department
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Behavior of Repeating Earthquake Sequences in Central California and the Implications for Subsurface Fault Creep

Description: Repeating earthquakes (REs) are sequences of events that have nearly identical waveforms and are interpreted to represent fault asperities driven to failure by loading from aseismic creep on the surrounding fault surface at depth. We investigate the occurrence of these REs along faults in central California to determine which faults exhibit creep and the spatio-temporal distribution of this creep. At the juncture of the San Andreas and southern Calaveras-Paicines faults, both faults as well as … more
Date: July 9, 2007
Creator: Templeton, D C; Nadeau, R & Burgmann, R
Partner: UNT Libraries Government Documents Department
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Probing Late Neutrino Mass Properties With SupernovaNeutrinos

Description: Models of late-time neutrino mass generation contain new interactions of the cosmic background neutrinos with supernova relic neutrinos (SRNs). Exchange of an on-shell light scalar may lead to significant modification of the differential SRN flux observed at earth. We consider an Abelian U(1) model for generating neutrino masses at low scales, and show that there are cases for which the changes induced in the flux allow one to distinguish the Majorana or Dirac nature of neutrinos, as well as th… more
Date: August 8, 2007
Creator: Baker, Joseph; Goldberg, Haim; Perez, Gilad & Sarcevic, Ina
Partner: UNT Libraries Government Documents Department
open access

Towards a Sustainable Energy Balance: Progressive Efficiency and the Return of Energy Conservation

Description: We argue that a primary focus on energy efficiency may not be sufficient to slow (and ultimately reverse) the growth in total energy consumption and carbon emissions. Instead, policy makers need to return to an earlier emphasis on"conservation," with energy efficiency seen as a means rather than an end in itself. We briefly review the concept of"intensive" versus"extensive" variables (i.e., energy efficiency versus energy consumption), and why attention to both con… more
Date: August 13, 2007
Creator: Diamond, Rick; Harris, Jeff; Diamond, Rick; Iyer, Maithili; Payne, Christopher; Blumstein, Carl et al.
Partner: UNT Libraries Government Documents Department
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CAMS/LLNL Ion Source Efficiency Revisited

Description: No Description Available.
Date: April 17, 2007
Creator: Fallon, S. J.; Guilderson, T. P. & Brown, T. A.
Partner: UNT Libraries Government Documents Department
open access

Plasma Suppression of Large Scale Structure Formation in the Universe

Description: We point out that during the reionization epoch of the cosmic history, the plasma collective effect among the ordinary matter would suppress the large scale structure formation. The imperfect Debye shielding at finite temperature would induce a residual long-range electrostatic potential which, working together with the baryon thermal pressure, would counter the gravitational collapse. As a result the effective Jean's length, {tilde {lambda}}{sub J}, is increased by a factor, {tilde {lambda}}{s… more
Date: December 10, 2007
Creator: Chen, Pisin & Lai, Kwang-Chang
Partner: UNT Libraries Government Documents Department
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An Update on the Status of the NIF Power Conditioning System

Description: The National Ignition Facility (NIF) Power Conditioning System provides the pulsed excitation required to drive flashlamps in the laser's optical amplifiers. Modular in design, each of the 192 Main Energy Storage Modules (MESMs) stores up to 2.2 MJ of electrical energy in its capacitor bank before delivering the energy to 20 pairs of flashlamps in a 400 {micro}s pulse (10% power points). The peak current of each MESM discharge is 0.5 MA. Production, installation, commissioning and operation of … more
Date: September 6, 2007
Creator: Arnold, P. A.; Hulsey, S.; Ullery, G. T.; Petersen, D. E.; Pendleton, D. L.; Ollis, C. W. et al.
Partner: UNT Libraries Government Documents Department
open access

SOFC Interconnect Work at NETL

Description: No Description Available.
Date: December 1, 2007
Creator: Jablonski, P. D. & Alman, D. E.
Partner: UNT Libraries Government Documents Department
open access

CFD Analysis of Turbulent Flow Phenomena in the Lower Plenum of a Prismatic Gas-Cooled Reactor

Description: This paper is concerned with the implementation of a computational model of turbulent flow in a section of the lower plenum of Very High Temperature Reactor (VHTR). The proposed model has been encoded in a state-of-the-art CFD code, NPHASE. The results of NPHASE predictions have been compared against the experimental data collected using a scaled model of a sub-region in the lower plenum of a modular prismatic gas-cooled reactor. It has been shown that the NPHASE-based model is capable of predi… more
Date: September 1, 2007
Creator: Gallaway, T.; Antal, S.P.; Podowski, M.Z. & Guillen, D.P.
Partner: UNT Libraries Government Documents Department
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