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LENS repair and modification of metal NW components:materials and applications guide.

Description: Laser Engineered Net Shaping{trademark} (LENS{reg_sign}) is a unique, layer additive, metal manufacturing technique that offers the ability to create fully dense metal features and components directly from a computer solid model. LENS offers opportunities to repair and modify components by adding features to existing geometry, refilling holes, repairing weld lips, and many other potential applications. The material deposited has good mechanical properties with strengths typically slightly highe… more
Date: November 1, 2006
Creator: Smugeresky, John E. (Sandia National Laboratories, Livermore, CA); Gill, David Dennis; Oberhaus, Jason (BWXT Y-12); Adams, Thad (Savannah River National Laboratory) & VanCamp, Chad (Kansas City Plant)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling Hemispheric Detonation Experiments in 2-Dimensions

Description: Experiments have been performed with LX-17 (92.5% TATB and 7.5% Kel-F 800 binder) to study scaling of detonation waves using a dimensional scaling in a hemispherical divergent geometry. We model these experiments using an arbitrary Lagrange-Eulerian (ALE3D) hydrodynamics code, with reactive flow models based on the thermo-chemical code, Cheetah. The thermo-chemical code Cheetah provides a pressure-dependent kinetic rate law, along with an equation of state based on exponential-6 fluid potential… more
Date: June 22, 2006
Creator: Howard, W M; Fried, L E; Vitello, P A; Druce, R L; Phillips, D; Lee, R et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Contact Interface Verification for DYNA3D Scenario 1: Basic Contact

Description: A suite of test problems has been developed to examine contact behavior within the nonlinear, three-dimensional, explicit finite element analysis (FEA) code DYNA3D (Lin, 2005). The test problems address the basic functionality of the contact algorithms, including the behavior of various kinematic, penalty, and Lagrangian enforcement formulations. The results from the DYNA3D analyses are compared to closed form solutions to verify the contact behavior. This work was performed as part of the Veri… more
Date: May 10, 2006
Creator: McMichael, L D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Monte Carlo Particle Transport Capability for Inertial Confinement Fusion Applications

Description: A time-dependent massively-parallel Monte Carlo particle transport calculational module (ParticleMC) for inertial confinement fusion (ICF) applications is described. The ParticleMC package is designed with the long-term goal of transporting neutrons, charged particles, and gamma rays created during the simulation of ICF targets and surrounding materials, although currently the package treats neutrons and gamma rays. Neutrons created during thermonuclear burn provide a source of neutrons to the … more
Date: November 6, 2006
Creator: Brantley, P. S. & Stuart, L. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Guinier Camera for Sr Powder Diffraction: High Resolution and High Throughput.

Description: The paper describe a new powder diffraction instrument for synchrotron radiation sources which combines the high throughput of a position-sensitive detector system with the high resolution normally only provided by a crystal analyzer. It uses the Guinier geometry which is traditionally used with an x-ray tube source. This geometry adapts well to the synchrotron source, provided proper beam conditioning is applied. The high brightness of the SR source allows a high resolution to be achieved. Whe… more
Date: May 28, 2006
Creator: Siddons, D. P.; Hulbert, S. L. & Stephens, P. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New Dimensions for Wound Strings:The Modular Transform of Geometry to Topology

Description: We show, using a theorem of Milnor and Margulis, that string theory on compact negatively curved spaces grows new effective dimensions as the space shrinks, generalizing and contextualizing the results in [1]. Milnor's theorem relates negative sectional curvature on a compact Riemannian manifold to exponential growth of its fundamental group, which translates in string theory to a higher effective central charge arising from winding strings. This exponential density of winding modes is related … more
Date: December 18, 2006
Creator: McGreevy, John; Silverstein, Eva & Starr, David
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2005

Description: This report is the second annual report of a six-year project to evaluate the cumulative effects of habitat restoration projects in the Columbia River Estuary, conducted by Pacific Northwest National Laboratory's Marine Sciences Laboratory, NOAA's National Marine Fisheries Service Pt. Adams Biological Field Station, and the Columbia River Estuary Study Taskforce for the US Army Corps of Engineers. In 2005, baseline data were collected on two restoration sites and two associated reference sites … more
Date: December 20, 2006
Creator: Diefenderfer, Heida L.; Thom, Ronald M.; Borde, Amy B.; Roegner, G. C.; Whiting, Allan H.; Johnson, Gary E. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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TRADITIONAL AND DIGITAL AUTORADIOGRAPHY TECHNIQUES: A COMPARISON STUDY

Description: This report fulfills the FY 2006 Enhanced Surveillance Campaign Level 3 milestones for Task TSR 11.1 as defined in the execution plan [1, 2]. The purpose of this task is to reduce the cycle time necessary to complete analytical evaluations required for surveillance of reservoirs. The development of the digital autoradiography system supports this task. The digital autoradiography system is currently operational and ready for implementation in reservoir surveillance performed in the Materials Te… more
Date: August 29, 2006
Creator: Gibbs, K & Carol Kestin, C
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hot dense matter creation in short-pulse laser interaction with tamped foils

Description: The possibility of producing hot dense matter has important applications for the understanding of transport processes in inertial confinement fusion (ICF) [1] and laboratory astrophysics experiments [2]. While the success of ICF requires the correct solution of a complex interaction between laser coupling, equation-of-state, and particle transport problems, the possibility of experimentally recreating conditions found during the ignition phase in a simplified geometry is extremely appealing. In… more
Date: August 15, 2006
Creator: Chen, S.; Pasley, J.; Beg, F.; Gregori, G.; Evans, R. G.; Notley, M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Np Incorporation into Uranyl Alteration Phases: A Quantum Mechanical Approach

Description: Neptunium is a major contributor to the long-term radioactivity in a geologic repository for spent nuclear fuel (SNF) due to its long half-life (2.1 million years). The mobility of Np may be decreased by incorporation into the U{sup 6+} phases that form during the corrosion of SNF. The ionic radii of Np (0.089nm) and U (0.087nm) are similar, as is their chemistry. Experimental studies have shown Np can be incorporated into uranyl phases at concentrations of {approx} 100 ppm. The low concentrati… more
Date: September 5, 2006
Creator: Shuller, L. C.; Ewing, R. C. & Becker, U.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of Vacuum Insulator Flashover for Pulse Lengths of Multi-Microseconds

Description: We are studying the flashover of vacuum insulators for applications where high voltage conditioning of the insulator and electrodes is not practical and for pulse lengths on the order of several microseconds. The study is centered about experiments performed with a 100-kV, 10-ms pulsed power system and supported by a combination of theoretical and computational modeling. The base line geometry is a cylindrically symmetric, +45{sup o} insulator between flat electrodes. In the experiments, flasho… more
Date: July 31, 2006
Creator: Houck, T. L.; Goerz, D. A.; Javedani, J. B.; Lauer, E. J.; Tully, L. K. & Vogtlin, G. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quantum Monte-Carlo Study of Electron Correlation in Heterostructure Quantum Dots

Description: The goal of this project is to study electron correlation in a confined geometry (quantum dots) within the two-dimensional quantum well in the sandwiches of two semiconductor materials. For these systems one is able to tune the electronic properties by controlling the size and the electron number, creating tremendous potential for novel applications. Much effort in this emerging field has been devoted to producing entangled states that are required for quantum information processing. At the sam… more
Date: November 12, 2006
Creator: Chou, Mei-Yin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Criticality Potential of Waste Packages Containing DOE SNF Affected by Igneous Intrusion

Description: The Department of Energy (DOE) is currently preparing an application to submit to the U.S. Nuclear Regulatory Commission for a construction authorization for a monitored geologic repository. The repository will contain spent nuclear fuel (SNF) and defense high-level waste (DHLW) in waste packages placed in underground tunnels, or drifts. The primary objective of this paper is to perform a criticality analysis for waste packages containing DOE SNF affected by a disruptive igneous intrusion event… more
Date: February 7, 2006
Creator: Kimball, D. S. & Sanders, C. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electromagnetic Confined Plasma Target for Interaction Studies with Intense Laser Fields

Description: The paper describes a novel application of an electron beam ion trap as a plasma target facility for intense laser-plasma interaction studies. The low density plasma target ({approx}10{sup 13}/cm{sup 3}) is confined in a mobile cryogenic electromagnetic charged particle trap, with the magnetic confinement field of 1-3T maintained by a superconducting magnet. Ion plasmas for a large variety of ion species and charge states are produced and maintained within the magnetic field and the space charg… more
Date: August 9, 2006
Creator: Zielbauer, B.; Ursescu, U.; Trotsenko, S.; Spillmann, U.; Schuch, R.; Stohlker, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multi-Grained Level of Detail for Rendering Complex Meshes Using a Hierarchical Seamless Texture Atlas

Description: Previous algorithms for view-dependent level of detail provide local mesh refinements either at the finest granularity or at a fixed, coarse granularity. The former provides triangle-level adaptation, often at the expense of heavy CPU usage and low triangle rendering throughput; the latter improves CPU usage and rendering throughput by operating on groups of triangles. We present a new multiresolution hierarchy and associated algorithms that provide adaptive granularity. This multi-grained hier… more
Date: November 6, 2006
Creator: Niski, Krzysztof; Purnomo, Budirijanto & Cohen, Jonathan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fatique Resistant, Energy Efficient Welding Program, Final Technical Report

Description: The program scope was to affect the heat input and the resultant weld bead geometry by synchronizing robotic weave cycles with desired pulsed waveform shapes to develop process parameters relationships and optimized pulsed gas metal arc welding processes for welding fatique-critical structures of steel, high strength steel, and aluminum. Quality would be addressed by developing intelligent methods of weld measurement that accurately predict weld bead geometry from process information. This prog… more
Date: May 25, 2006
Creator: Egland, Keith & Ludewig, Howard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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FY05 LDRD Final ReportNanomaterials for Radiation Detection

Description: We have demonstrated that it is possible to enhance current radiation detection capability by manipulating the materials at the nano level. Fabrication of three-dimensional (3-D) nanomaterial composite for radiation detection has great potential benefits over current semiconductor- and scintillation-based technologies because of the precise control of material-radiation interaction and modulation of signal output. It is also a significant leap beyond current 2-D nanotechnology. Moreover, since … more
Date: February 6, 2006
Creator: Wang, T. F.; Letant, S. E.; Nikolic, R. J. & Chueng, C. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of Transport Properties of Fractures: Final Report

Description: We proposed to study several key factors controlling the character and evolution of fracture system permeability and transport processes. We suggest that due to surface roughness and the consequent channeling in single fractures and in fracture intersections, the tendency of a fracture system to plug up, remain permeable, or for permeability to increase due to chemical dissolution/precipitation conditions will depend strongly on the instantaneous flow channel geometry. This geometry will change… more
Date: June 30, 2006
Creator: Brown, Stephen R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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POTENTIAL SCALE DEPENDENCE OF EFFECTIVE MATRIX DIFFUSION COEFFICIENT

Description: It is well known that matrix diffusion (mass transfer between fractures and the rock matrix through molecular diffusion) can significantly retard solute transport processes in fractured rock, and therefore is important for analyzing a variety of problems, including geological disposal of nuclear waste. Matrix-diffusion-coefficient values measured from small rock samples in the laboratory are generally used for modeling field-scale solute transport in fractured rock. However, by compiling result… more
Date: March 13, 2006
Creator: Liu, H.; Zhou, Q. & Zhang, Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simulation studies of non-neutral plasma equilibria in anelectrostatic trap with magnetic mirror

Description: The equilibrium of an infinitely long, strongly magnetized, non-neutral plasma confined in a Penning-Malmberg trap with an additional mirror coil has been solved analytically [J. Fajans, Phys. Plasmas 10, 1209 (2003)] and shown to exhibit unusual features. Particles not only reflect near the mirror in the low field region, but also may be weakly trapped in part of in the high field region. The plasma satisfies a Boltzmann distribution along field lines; however, the density and the potential va… more
Date: June 1, 2006
Creator: Gomberoff, K.; Fajans, J.; Wurtele, J.; Friedman, A.; Grote, D. P.; Cohen, R. H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Geometrically induced metastability and holography

Description: We construct metastable configurations of branes and anti-branes wrapping 2-spheres inside local Calabi-Yau manifolds and study their large N duals. These duals are Calabi-Yau manifolds in which the wrapped 2-spheres have been replaced by 3-spheres with flux through them, and supersymmetry is spontaneously broken. The geometry of the non-supersymmetric vacuum is exactly calculable to all orders of the't Hooft parameter, and to the leading order in 1/N. The computation utilizes the same matr… more
Date: October 23, 2006
Creator: Aganagic, Mina; Aganagic, Mina; Beem, Christopher; Seo, Jihye & Vafa, Cumrun
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Onset of Convection in Two Liquid Layers with Phase Change

Description: We perform linear stability calculations for horizontal fluid bilayers that can undergo a phase transformation, taking into account both buoyancy effects and thermocapillary effects in the presence of a vertical temperature gradient. We compare the familiar case of the stability of two immiscible fluids in a bilayer geometry with the less-studied case that the two fluids represent different phases of a single-component material, e.g., the water-steam system. The two cases differ in their interf… more
Date: September 14, 2006
Creator: McFadden, G B; Coriell, S R; Gurski, K F & Cotrell, D L
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Partner: UNT Libraries Government Documents Department
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Esimation of field-scale thermal conductivities of unsaturatedrocks from in-situ temperature data

Description: A general approach is presented here which allows estimationof field-scale thermal properties of unsaturated rock using temperaturedata collected from in situ heater tests. The approach developed here isused to determine the thermal conductivities of the unsaturated host rockof the Drift Scale Test (DST) at Yucca Mountain, Nevada. The DST wasdesigned to obtain thermal, hydrological, mechanical, and chemical (THMC)data in the unsaturated fractured rock of Yucca Mountain. Sophisticatednumerical m… more
Date: June 26, 2006
Creator: Mukhopadhyay, Sumit; Tsang, Yvonne W. & Birkholzer, Jens T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Simulation studies of non-neutral plasma equilibria in an electrostatic trap with a magnetic mirror

Description: The equilibrium of an infinitely long, strongly magnetized, non-neutral plasma confined in a Penning-Malmberg trap with an additional mirror coil has been solved analytically [J. Fajans, Phys. Plasmas 10, 1209 (2003)] and shown to exhibit unusual features. Particles not only reflect near the mirror in the low field region, but also may be weakly trapped in part of in the high field region. The plasma satisfies a Boltzmann distribution along field lines; however, the density and the potential va… more
Date: June 5, 2006
Creator: Gomberoff, K; Fajans, J; Wurtele, J; Friedman, A; Grote, D P; Cohen, R H et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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