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MONITORING WASTE HEAT REJECTION TO THE ENVIRONMENT VIA REMOTE SENSING

Description: Nuclear power plants typically use waste heat rejection systems such as cooling lakes and natural draft cooling towers. These systems are designed to reduce cooling water temperatures sufficiently to allow full power operation even during adverse meteorological conditions. After the power plant is operational, the performance of the cooling system is assessed. These assessments usually rely on measured temperatures of the cooling water after it has lost heat to the environment and is being pump… more
Date: January 13, 2009
Creator: Garrett, A
Partner: UNT Libraries Government Documents Department
open access

Toward a simple molecular understanding of sum frequency generation at air-water interfaces

Description: Second-order vibrational spectroscopies successfully isolate signals from interfaces, but they report on intermolecular structure in a complicated and indirect way. Here we adapt a perspective on vibrational response developed for bulk spectroscopies to explore the microscopic fluctuations to which sum frequency generation (SFG), a popular surface-specific measurement, is most sensitive. We focus exclusively on inhomogeneous broadening of spectral susceptibilities for OH stretching of HOD as a … more
Date: January 13, 2009
Creator: Noah-Vanhoucke, Joyce; Smith, Jared D. & Geissler, Phillip L.
Partner: UNT Libraries Government Documents Department
open access

Discontinuous Galerkin solution of the Navier-Stokes equations on deformable domains

Description: We describe a method for computing time-dependent solutions to the compressible Navier-Stokes equations on variable geometries. We introduce a continuous mapping between a fixed reference configuration and the time varying domain, By writing the Navier-Stokes equations as a conservation law for the independent variables in the reference configuration, the complexity introduced by variable geometry is reduced to solving a transformed conservation law in a fixed reference configuration, The spati… more
Date: January 13, 2009
Creator: Persson, P.-O.; Bonet, J. & Peraire, J.
Partner: UNT Libraries Government Documents Department
open access

Stability of Numerical Interface Conditions for Fluid/Structure Interaction

Description: In multi physics computations, where a compressible fluid is coupled with a linearly elastic solid, it is standard to enforce continuity of the normal velocities and of the normal stresses at the interface between the fluid and the solid. In a numerical scheme, there are many ways that the velocity- and stress-continuity can be enforced in the discrete approximation. This paper performs a normal mode analysis to investigate the stability of different numerical interface conditions for a model p… more
Date: August 13, 2009
Creator: Banks, J W & Sjogreen, B
Partner: UNT Libraries Government Documents Department
open access

Tantalum-Tungsten Oxide Thermite Composite Prepared by Sol-Gel Synthesis and Spark Plasma Sintering

Description: Energetic composite powders consisting of sol-gel derived nanostructured tungsten oxide were produced with various amounts of micrometer-scale tantalum fuel metal. Such energetic composite powders were ignition tested and results show that the powders are not sensitive to friction, spark and/or impact ignition. Initial consolidation experiments, using the High Pressure Spark Plasma Sintering (HPSPS) technique, on the sol-gel derived nanostructured tungsten oxide produced samples with higher rel… more
Date: February 13, 2009
Creator: Cervantes, O; Kuntz, J; Gash, A & Munir, Z
Partner: UNT Libraries Government Documents Department
open access

Opto-electrical characterization and X-ray mapping of large-volume cadmium zinc telluride radiation detectors

Description: Large-volume cadmium zinc telluride (CZT) radiation detectors would greatly improve radiation detection capabilities and, therefore, attract extensive scientific and commercial interests. CZT crystals with volumes as large as hundreds of centimeters can be achieved today due to improvements in the crystal growth technology. However, the poor performance of large-volume CZT detectors is still a challenging problem affecting the commercialization of CZT detectors and imaging arrays. We have emplo… more
Date: April 13, 2009
Creator: Yang, G.; Bolotnikov, A.E.; Camarda, G.S.; Cui, Y.; Hossain, A.; Yao, H.W. et al.
Partner: UNT Libraries Government Documents Department
open access

WInd-and-react Bi-2212 coil development for accelerator magnets

Description: Sub-scale coils are being manufactured and tested at Lawrence Berkeley National Laboratory in order to develop wind-and-react Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (Bi-2212) magnet technology for future graded accelerator magnet use. Previous Bi-2212 coils showed significant leakage of the conductors core constituents to the environment, which can occur during the partial melt reaction around 890 C in pure oxygen. The main origin of the observed leakage is intrinsic leakage of the wires, and th… more
Date: October 13, 2009
Creator: Godeke, A.; Acosta, P.; Cheng, D.; Dietderich, D. R.; Mentink, M. G. T.; Prestemon, S. O. et al.
Partner: UNT Libraries Government Documents Department
open access

Characterizing the Nano and Micro Structure of Concrete toImprove its Durability

Description: New and advanced methodologies have been developed to characterize the nano and microstructure of cement paste and concrete exposed to aggressive environments. High resolution full-field soft X-ray imaging in the water window is providing new insight on the nano scale of the cement hydration process, which leads to a nano-optimization of cement-based systems. Hard X-ray microtomography images of ice inside cement paste and cracking caused by the alkali?silica reaction (ASR) enables three-dimens… more
Date: January 13, 2009
Creator: Monteiro, Paulo J. M.; Kirchheim, A. P.; Chae, S.; Fischer, Peter; MacDowell, Alastair A.; Schaible, Eirc et al.
Partner: UNT Libraries Government Documents Department
open access

Theory of AC Loss in Cables with 2G HTS Wire

Description: While considerable work has been done to understand AC losses in power cables made of first generation (1G) high temperature superconductor (HTS) wires, use of second generation (2G) HTS wires brings in some new considerations. The high critical current density of the HTS layer 2G wire reduces the surface superconductor hysteretic losses. Instead, gap and polygonal losses, flux transfer losses in imbalanced two layer cables and ferromagnetic losses for wires with NiW substrates constitute the p… more
Date: September 13, 2009
Creator: Clem, J.R. & Malozemoff, A.P.
Partner: UNT Libraries Government Documents Department
open access

EFFECT OF PRETREATMENT ON PT-CO/C CATHODE CATALYSTS FOR THE OXYGEN-REDUCTION REACTION

Description: In order to reduce the precious metal loading without sacrificing activity and stability, a new method for the preparation of bimetallic catalysts is proposed. Currently, Pt-alloy particles, with 2 to 3 nm in diameter, are loaded on high surface area carbon supports. Of the Pt loaded, only the surface atoms interact with the reactants. In order to increase the Pt utilization per metal particle the new process for catalyst preparation will incorporate a non-noble transition metal core coated wit… more
Date: May 13, 2009
Creator: Fox, E.
Partner: UNT Libraries Government Documents Department
open access

The BARD1 C-Terminal Domain Structure and Interactions with Polyadenylation Factor CstF-50

Description: The BARD1 N-terminal RING domain binds BRCA1 while the BARD1 C-terminal ankyrin and tandem BRCT repeat domains bind CstF-50 to modulate mRNA processing and RNAP II stability in response to DNA damage. Here we characterize the BARD1 structural biochemistry responsible for CstF- 50 binding. The crystal structure of the BARD1 BRCT domain uncovers a degenerate phosphopeptide binding pocket lacking the key arginine required for phosphopeptide interactions in other BRCT proteins.Small angle X-ray sca… more
Date: July 13, 2009
Creator: Edwards, Ross A.; Lee, Megan S.; Tsutakawa, Susan E.; Williams, R. Scott; Tainer, John A. & Glover, J. N. Mark
Partner: UNT Libraries Government Documents Department
open access

Structural Characterization of Doped GaSb Single Crystals by X-ray Topography

Description: We characterized GaSb single crystals containing different dopants (Al, Cd and Te), grown by the Czochralski method, by x-ray topography and high angular resolution x-ray diffraction. Lang topography revealed dislocations parallel and perpendicular to the crystal's surface. Double-crystal GaSb 333 x-ray topography shows dislocations and vertical stripes than can be associated with circular growth bands. We compared our high-angular resolution x-ray diffraction measurements (rocking curves) with… more
Date: September 13, 2009
Creator: Honnicke, M. G.; Mazzaro, I.; Manica, J.; Benine, E.; da Costa, E. M.; Dedavid, B. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Crossover transition in bag-like models

Description: We formulate a simple model for a gas of extended hadrons at zero chemical potential by taking inspiration from the compressible bag model. We show that a crossover transition qualitatively similar to lattice QCD can be reproduced by such a system by including some appropriate additional dynamics. Under certain conditions, at high temperature, the system consist of a finite number of infinitely extended bags,which occupy the entire space. In this situation the system behaves as an ideal gas of … more
Date: March 13, 2009
Creator: Ferroni, Lorenzo & Koch, Volker
Partner: UNT Libraries Government Documents Department
open access

THE HIGH TEMPERATURE CHEMICAL REACTIVITY OF LI2O

Description: The ultimate purpose of this study was to investigate the use of a Li-Ca mixture for direct reduction of actinide oxides to actinide metals at temperatures below 1500 C. For such a process to be successful, the products of the reduction reaction, actinide metals, Li{sub 2}O, and CaO, must all be liquid at the reaction temperature so the resulting actinide metal can coalesce and be recovered as a monolith. Since the established melting temperature of Li{sub 2}O is in the range 1427-1700 C and th… more
Date: November 13, 2009
Creator: Kessinger, G. & Missimer, D.
Partner: UNT Libraries Government Documents Department
open access

Exposing the non-collectivity in elliptic flow

Description: We show that backward-forward elliptic asymmetry correlations provide an experimentally accessible observable which distinguishes between collective and non-collective contributions to the observed elliptic asymmetry v2 in relativistic heavy ion collisions. The measurement of this observable will reveal the momentum scale at which collective expansion seizes and where the elliptic asymmetry is dominated by (semi)-hard processes. In addition, the knowledge of the actual magnitude of the collecti… more
Date: February 13, 2009
Creator: Liao, Jinfeng & Koch, Volker
Partner: UNT Libraries Government Documents Department
open access

Measurements of the Total Charge-Changing Cross Sections for Collisions of Fast Ions with Target Gas Using High Current Experiment

Description: The sum of ionization and charge-exchange cross sections of several gas targets (H2, N2, He, Ne, Kr, Xe, Ar, and water vapor) impacted by 1MeV K+ beam are measured. In a high current ion beam, the self-electric field of the beam is high enough that ions produced from the gas ionization or charge exchange by the ion beam are quickly swept to the sides of accelerator. The flux of the expelled ions is measured by a retarding field analyzer. This allows accurate measuring of the total charge-changi… more
Date: April 13, 2009
Creator: Covo, Michel Kireeff; Molvik, Arthur W.; Kaganovich, Igor D.; Shnidman, Ariel & Vujic, Jasmina L.
Partner: UNT Libraries Government Documents Department
open access

DIFFERENTIAL SENSITIVITY OF MALE GERM CELLS TO MAINSTREAM AND SIDESTREAM TOBACCO SMOKE IN THE MOUSE

Description: Cigarette smoking in men has been associated with increased chromosomal abnormalities in sperm and with increased risks for spontaneous abortions, birth defects and neonatal death. Little is known, however, about the reproductive consequences of paternal exposure to second-hand smoke. We used a mouse model to investigate the effects of paternal exposure to sidestream (SS) smoke, the main constituent of second-hand smoke, on the genetic integrity and function of sperm, and to determine whether m… more
Date: March 13, 2009
Creator: Polyzos, Aris; Schmid, Thomas Ernst; Pina-Guzman, Belem; Quintanilla-Vega, Betzabet & Marchetti, Francesco
Partner: UNT Libraries Government Documents Department
open access

Proliferation Risks of Fusion Energy: Clandestine Production, Covert Production, and Breakout

Description: Nuclear proliferation risks from fusion associated with access to weapon-usable material can be divided into three main categories: 1) clandestine production of fissile material in an undeclared facility, 2) covert production of such material in a declared and safeguarded facility, and 3) use of a declared facility in a breakout scenario, in which a state begins production of fissile material without concealing the effort. In this paper we address each of these categories of risk from fusion. F… more
Date: August 13, 2009
Creator: R.J. Goldston, A. Glaser, A.F. Ross
Partner: UNT Libraries Government Documents Department
open access

Search for b\to u Transitions in \Bz \to \Dz \Kstarz Decays

Description: We present a study of the decays B{sup 0} {yields} D{sup 0} K*{sup 0} and B{sup 0} {yields} {bar D}{sup 0} K*{sup 0} with K*{sup 0} {yields} K{sup +}{pi}{sup -}. The D{sup 0} and the {bar D}{sup 0} mesons are reconstructed in the final states f = K{sup +} {pi}{sup -}, K{sup +}{pi}{sup -}{pi}{sup 0}, K{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} and their charge conjugates. Using a sample of 465 million B{bar B} pairs collected with the BABAR detector at PEP-II asymmetric-energy e{sup +}e{sup -} col… more
Date: April 13, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Progress Testing TRANSP-TORIC Simulations of ICRH in JE

Description: Introduction - Ion Cyclotron Range of Frequency (ICRF) waves are candidates for heating (ICRH), current drive, and possible flow drive in ITER and future tokamaks. There are considerable challenges developing the technology of ICRF systems and the tools for assessing effects on plasma performance. These tools are important both for guiding present experiments and for indicating efforts for future research. This paper addresses some of the tools for simulating ICRH. The TORIC ICRF full-wave code… more
Date: August 13, 2009
Creator: Budny, R V; McCune, D; Mayoral, M -L; Ongena, J; Van Eester, D; Conboy, J et al.
Partner: UNT Libraries Government Documents Department
open access

Evidence for Nodal Superconductivity in LaFePO from Scanning SQUID Susceptometry

Description: We measure changes in the penetration depth {lambda} of the T{sub c} {approx} 6 K superconductor LaFePO. In the process scanning SQUID susceptometry is demonstrated as a technique for accurately measuring local temperature-dependent changes in {lambda}, making it ideal for studying early or difficult-to-grow materials. {lambda} of LaFePO is found to vary linearly with temperature from 0.36 to {approx} 2 K, with a slope of 143 {+-} 15 {angstrom}/K, suggesting line nodes in the superconducting or… more
Date: April 13, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; /Stanford U., Geballe Lab. /SLAC; Huber, Martin E.; /Colorado U., Denver; Analytis, James G. et al.
Partner: UNT Libraries Government Documents Department
open access

Toward an Optimal Position for IVC Filters: Computational Modeling of the Impact of Renal Vein Inflow

Description: The purpose of this report is to evaluate the hemodynamic effects of renal vein inflow and filter position on unoccluded and partially occluded IVC filters using three-dimensional computational fluid dynamics. Three-dimensional models of the TrapEase and Gunther Celect IVC filters, spherical thrombi, and an IVC with renal veins were constructed. Hemodynamics of steady-state flow was examined for unoccluded and partially occluded TrapEase and Gunther Celect IVC filters in varying proximity to th… more
Date: July 13, 2009
Creator: Wang, S. L. & Singer, M. A.
Partner: UNT Libraries Government Documents Department
open access

THE SETTLERS PHOTOGRAPHIC COLLECTION 1894 - 1945 & THE DUPONT PHOTOGRAPHIC COLLECTION 1943 - 1945 BRINGING HISTORY TO LIFE IN SOUTH CENTRAL WASHINGTON

Description: Washington is called the 'Evergreen State' and it evokes images like this of lush forests, lakes and mountains. However, such images apply primarily to the half of the state west of the Cascade Mountains, where we are today. Eastern Washington state is quite a different matter and I want to draw your attention to a portion of Eastern Washington that is the focus ofmy presentation to you this morning. This image was taken on a part of the Department of Energy's Hanford Site, a 586-square mile go… more
Date: July 13, 2009
Creator: PH.D., SHULTZ CR (KIT)
Partner: UNT Libraries Government Documents Department
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