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Modeling Hydraulic Responses to Meteorological Forcing: fromCanopy to Aquifer

Description: An understanding of the hydrologic interactions amongatmosphere, land surface, and subsurface is one of the keys tounderstanding the water cycling system that supports our life system onearth. Properly modeling such interactionsis a difficult task because oftheinherent coupled processes and complex feedback structures amongsubsystems. In this paper, we present a model that simulates thelandsurface and subsurface hydrologic response to meteorological forcing.This model combines a state of the ar… more
Date: February 8, 2007
Creator: Pan, Lehua; Jin, Jiming; Miller, Norman; Wu, Yu-Shu & Bodvarsson,Gudmundur
Partner: UNT Libraries Government Documents Department
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Slow Waves in Fractures Filled with Viscous Fluid

Description: Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves, and therefore, their properties need to be incorporated in more realistic models. In this study, a fracture is modeled as an infinite layer of viscous fluid bounded by two elastic half-spaces with identical parameters. For small fracture thickness, I obtain a simple dispersion equation for wave-propagation velocity. This velocity is much smaller than the velocity of a fluid wave in a Biot-type so… more
Date: January 8, 2008
Creator: Korneev, Valeri
Partner: UNT Libraries Government Documents Department
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Results from the B Factories

Description: These proceedings are based on lectures given at the Helmholtz International Summer School Heavy Quark Physics at the Bogoliubov Laboratory of Theoretical Physics, Dubna, Russia, during August 2008. I review the current status of CP violation in B meson decays from the B factories. These results can be used, along with measurements of the sides of the Unitarity Triangle, to test the CKM mechanism. In addition I discuss experimental studies of B decays to final states with 'spin-one' particles.
Date: January 8, 2009
Creator: Bevan, A. & /Queen Mary, U. of London
Partner: UNT Libraries Government Documents Department
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Composite Analysis of Llw Disposal Facilities at the U. S. Department of Energy's Savannah River Site

Description: Composite Analyses (CA's) are required per DOE Order 435.1 [1], in order to provide a reasonable expectation that DOE low-level waste (LLW) disposal, high-level waste tank closure, and transuranic (TRU) waste disposal in combination with Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), Resource Conservation and Recovery Act (RCRA), and deactivation and decommissioning (D&D) actions, will not result in the need for future remedial actions in order to ensure rad… more
Date: January 8, 2009
Creator: Hiergesell, R. A.; Phifer, M. A. & Smith, F. G.
Partner: UNT Libraries Government Documents Department
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Diagnostic Components in Harsh Radiation Environments: Possible Overlap in R&D Requirements of IC and MF Systems

Description: The next generation of large scale fusion devices--ITER/LMJ/NIF--will require diagnostic components to operate in environments far more severe than those encountered in present facilities. This harsh environment will be induced by fluxes of neutrons, gamma rays, energetic ions, electromagnetic radiation, and in some cases debris and shrapnel, at levels several orders of magnitude higher than those experienced in today's devices. For several years the question of possible synergy between inertia… more
Date: May 8, 2008
Creator: Bourgade, J. L.; Costley, A. E.; Reichle, R.; Hodgson, E. R.; Hsing, W.; Glebov, V. et al.
Partner: UNT Libraries Government Documents Department
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Measurement of D^0-\overline{D^0} Mixing using the Ratio of Lifetimes for the Decays D^0 \to K^-\pi^+, K^-K^+, and \pi^-\pi^+

Description: The authors present a measurement of D{sup 0}-{bar D}{sup 0} mixing parameters using the ratios of lifetimes extracted from a sample of D{sup 0} mesons produced through the process D*{sup +} {yields} D{sup 0}{pi}{sup +}, that decay to K{sup -}{pi}{sup +}, I{sup -}K{sup +}, or {pi}{sup -}{pi}{sup +}. the Cabibbo-suppressed modes K{sup -}K{sup +} and {pi}{sup -}{pi}{sup +} are compared to the Cabibbo-favored mode K{sup -}{pi}{sup +} to obtain a measurement of ycp, which in the limit of CP conserv… more
Date: January 8, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
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A QR accelerated volume-to-surface boundary condition for finite element solution of eddy current problems

Description: We are concerned with the solution of time-dependent electromagnetic eddy current problems using a finite element formulation on three-dimensional unstructured meshes. We allow for multiple conducting regions, and our goal is to develop an efficient computational method that does not require a computational mesh of the air/vacuum regions. This requires a sophisticated global boundary condition specifying the total fields on the conductor boundaries. We propose a Biot-Savart law based volume-to-… more
Date: September 8, 2006
Creator: White, D; Fasenfest, B; Rieben, R & Stowell, M
Partner: UNT Libraries Government Documents Department
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Modeling Free Convection Flow of Liquid Hydrogen within a Cylindrical Heat Exchanger Cooled to 14 K

Description: A liquid hydrogen in a absorber for muon cooling requires that up to 300 W be removed from 20 liters of liquid hydrogen. The wall of the container is a heat exchanger between the hydrogen and 14 K helium gas in channels within the wall. The warm liquid hydrogen is circulated down the cylindrical walls of the absorber by free convection. The flow of the hydrogen is studied using FEA methods for two cases and the heat transfer coefficient to the wall is calculated. The first case is when the wall… more
Date: May 8, 2004
Creator: Green, Michael A.; Yang, S. W.; Green, M. A. & Lau, W.
Partner: UNT Libraries Government Documents Department
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Density changes in Ga-stabilized delta-Pu, and what they mean

Description: Ga-stabilized {delta}-Pu undergoes small changes in density with time. These have been associated with four different causes: an initial reversible expansion that saturates after a short time; a continuous change that can be attributed to the in-growth of helium and actinide daughter products from the radioactive decay of plutonium; possible void swelling; and phase instability. We review our present understanding of these processes and evaluate their contributions to density changes. It is sho… more
Date: September 8, 2006
Creator: G.Wolfer, W.; Kubota, A.; S?derlind, P.; Landa, A.; Oudot, B.; Sadigh, B. et al.
Partner: UNT Libraries Government Documents Department
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The Genome of Methylobacillus Flagellatus, the Molecular Basis for Obligate Methylotrophy, and the Polyphyletic Origin of Methylotrophy

Description: Along with methane, methanol and methylated amines representimportant biogenic atmospheric constituents, thus not only methanotrophs,but also non-methanotrophic methylotrophs play a significant role inglobal carbon cycling. The complete genome of a model obligate methanoland methylamine utilizer, Methylobacillus flagellatus (strain KT) wassequenced. The genome is represented by a single circular chromosome ofapproximately 3 Mb pairs, potentially encoding a total of 2,766 proteins.Based on genom… more
Date: January 8, 2007
Creator: Chistoserdova, Ludmila; Lapidus, Alla; Han, Cliff; Goodwin, Lynne; Saunders, Liz; Brettin, Tom et al.
Partner: UNT Libraries Government Documents Department
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Design and Construction of Test Coils for the MICE Coupling Solenoid Magnet

Description: The superconducting coupling solenoid to be applied in the Muon Ionization Cooling Experiment (MICE) is made from copper matrix Nb-Ti conductors with inner radius of 750 mm, length of 285 mm and thickness of 102.5 mm at room temperature. The magnetic field up to 2.6 T at the magnet centerline is to keep the muons within the MICE RF cavities. Its self inductance is around 592 H and its magnet stored energy is about 13 MJ at a full current of 210 A for the worst operation case of the MICE channel… more
Date: August 8, 2008
Creator: Wang, Li; Pan, Heng; Xu, F.Y.; Liu, XioaKun; Chen, AnBin; Li, LanKai et al.
Partner: UNT Libraries Government Documents Department
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The Search for Muon Neutrinos from Northern HemisphereGamma-Ray Bursts with AMANDA

Description: We present the results of the analysis of neutrino observations by the Antarctic Muon and Neutrino Detector Array (AMANDA) correlated with photon observations of more than 400 gamma-ray bursts (GRBs) in the Northern Hemisphere from 1997 to 2003. During this time period, AMANDA's effective collection area for muon neutrinos was larger than that of any other existing detector. Based on our observations of zero neutrinos during and immediately prior to the GRBs in the dataset, we set the most stri… more
Date: May 8, 2007
Creator: Collaboration, IceCube; Klein, Spencer & Achterberg, A.
Partner: UNT Libraries Government Documents Department
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Laboratory Measurements of 3 --> 2 X-ray Line Ratios of F-like Fe XVIII and Ni XX

Description: The intensity ratios of 3 {yields} 2 emission lines of Fe XVIII and Ni XX were measured on the Livermore electron beam ion trap (EBIT-I) with a flat-field grating spectrometer. The results were compared with distorted-wave (DW) calculations obtained with the Flexible Atomic Code and recent close-coupling calculations using the R-matrix code. The measured 3s {yields} 2p/3d {yields} 2p ratios are about 20-40% higher than the theoretical values. When more extended configuration interaction is incl… more
Date: March 8, 2007
Creator: Gu, M F; Chen, H; Brown, G V; Beiersdorfer, P & Kahn, S M
Partner: UNT Libraries Government Documents Department
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SAVANNAH RIVER NATIONAL LABORATORY HYDROGEN TECHNOLOGY RESEARCH

Description: The Savannah River National Laboratory (SRNL) is a U.S. Department of Energy research and development laboratory located at the Savannah River Site (SRS) near Aiken, South Carolina. SRNL has over 50 years of experience in developing and applying hydrogen technology, both through its national defense activities as well as through its recent activities with the DOE Hydrogen Programs. The hydrogen technical staff at SRNL comprises over 90 scientists, engineers and technologists, and it is believed… more
Date: February 8, 2008
Creator: Danko, E
Partner: UNT Libraries Government Documents Department
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Comments on Shimony's 'An Analysis of Stapp's 'A bell-type theoremwithout hidden variables''

Description: The hidden-variable theorems of Bell and followers depend upon an assumption, namely the hidden-variable assumption, that conflicts with the precepts of quantum philosophy. Hence from an orthodox quantum perspective those theorems entail no faster-than-light transfer of information. They merely reinforce the ban on hidden variables. The need for some sort of faster-than-light information transfer can be shown by using counterfactuals instead of hidden variables. Shimony's criticism of that argu… more
Date: September 8, 2004
Creator: Stapp, Henry P.
Partner: UNT Libraries Government Documents Department
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HOT ELECTRON ENERGY DISTRIBUTIONS FROM ULTRA-INTENSE LASER SOLID INTERACTIONS

Description: We present experimental data of electron energy distributions from ultra-intense (>10{sup 19} W/cm{sup 2}) laser-solid interactions using the Rutherford Appleton Laboratory Vulcan petawatt laser. These measurements were made using a CCD-based magnetic spectrometer. We present details on the distinct effective temperatures that were obtained for a wide variety of targets as a function of laser intensity. It is found that as the intensity increases from 10{sup 17} W/cm{sup 2} to 10{sup 19} W/c… more
Date: December 8, 2005
Creator: Chen, H; Wilks, S C; Kruer, W L; Moon, S; Patel, N; Patel, P K et al.
Partner: UNT Libraries Government Documents Department
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Enhancement of Spin-Polarized Electron Emission from Strain-Compensated AlInGaAs-GaAsP Superlattices

Description: Resonance enhancement of the quantum efficiency of new polarized electron photocathodes based on a short-period strain-compensated AlInGaAs/GaAsP superlattice structure is reported. The superlattice is a part of an integrated Fabry-Perot optical cavity. We demonstrate that the Fabry-Perot resonator enhances the quantum efficiency by up to a factor 10 in the wavelength region of the main polarization maximum. The high structural quality implied by these results points to the very promising appli… more
Date: December 8, 2006
Creator: Roberts, J. S.; Yashin, Yu. P.; Mamaev, Yu. A.; Gerchikov, L. G.; Maruyama, T.; Luh, D. -A. et al.
Partner: UNT Libraries Government Documents Department
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Going with the flow: Life cycle costing for industrial pumping systems

Description: Industries worldwide depend upon pumping systems for theirdaily operation. These systems account for nearly 20 percent of theworld's industrial electrical energy demand and range from 25-50 percentof the energy usage in certain industrial plant operations. Purchasedecisions for a pump and its related system components are typicallybased upon a low bid, rather than the cost to operate the system over itslifetime. Additionally, plant facilities personnel are typically focussedon maintaining exist… more
Date: July 8, 2002
Creator: Tutterow, Vestal; Hovstadius, Gunnar & McKane, Aimee
Partner: UNT Libraries Government Documents Department
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Monitoring the chemistry and materials of the Magma Geothermal Binary Cycle Generating Plant

Description: The Magma Binary Cycle Plant at the East Mesa KGRA is the first geothermal generating plant of its kind in the US. In cooperation with the Magma Electric Company, the Pacific Northwest Laboratory conducted a DOE sponsored program at the plant to document the chemistry and materials performance during the first two years of operation. This paper describes the methods used, the instruments and the results.
Date: October 8, 1982
Creator: Shannon, Donald W.
Partner: UNT Libraries Government Documents Department
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Transition to Turbulence and Effect of Initial Conditions on 3D Compressible Mixing in Planar Blast-wave-driven Systems

Description: Perturbations on an interface driven by a strong blast wave grow in time due to a combination of Rayleigh-Taylor, Richtmyer-Meshkov, and decompression effects. In this paper, results from three-dimensional numerical simulations of such a system under drive conditions to be attainable on the National Ignition Facility [E. M. Campbell, Laser Part. Beams, 9(2), 209 (1991)] are presented. Using the multi-physics, adaptive mesh refinement, higher order Godunov Eulerian hydrocode, Raptor [L. H. Howel… more
Date: November 8, 2004
Creator: Miles, A R; Edwards, M J & Greenough, J A
Partner: UNT Libraries Government Documents Department
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In-situ monitoring of surface post-processing in large aperture fused silica optics with Optical Coherence Tomography

Description: Optical Coherence Tomography is explored as a method to image laser-damage sites located on the surface of large aperture fused silica optics during post-processing via CO{sub 2} laser ablation. The signal analysis for image acquisition was adapted to meet the sensitivity requirements for this application. A long-working distance geometry was employed to allow imaging through the opposite surface of the 5-cm thick optic. The experimental results demonstrate the potential of OCT for remote monit… more
Date: February 8, 2008
Creator: Guss, G M; Bass, I l; Hackel, R P; Mailhiot, C & Demos, S G
Partner: UNT Libraries Government Documents Department
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Use of Conducting Polymers for Electronic Communication with Redox Active Nanoparticles

Description: Nanoscale materials provide unique properties that will enable new technologies and enhance older ones. One area of intense activity in which nanoscale materials are being used is in the development of new functional materials for battery applications.1-4 This effort promises superior materials with properties that circumvent many of the problems associated with traditional battery materials. Previously we have worked on several approaches for using nanoscale materials for application as cathod… more
Date: August 8, 2004
Creator: Bazito, Fernanda; O'Brien, Robert & Buttry, Daniel A.
Partner: UNT Libraries Government Documents Department
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A New Stabilized Nodal Integration Approach

Description: A new stabilized nodal integration scheme is proposed and implemented. In this work, focus is on the natural neighbor meshless interpolation schemes. The approach is a modification of the stabilized conforming nodal integration (SCNI) scheme and is shown to perform well in several benchmark problems.
Date: February 8, 2006
Creator: Puso, M; Zywicz, E & Chen, J S
Partner: UNT Libraries Government Documents Department
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A general scaling relation for the critical current density inNb3Sn

Description: We review the scaling relations for the critical currentdensity (Jc) in Nb3Sn wires and include recent findings on the variationof the upper critical field (Hc2) with temperature (T) and A15composition. Measurements of Hc2(T) in inevitably inhomogeneous wires, aswell as analysis of literature results, have shown that all availableHc2(T) data can be accurately described by a single relation from themicroscopic theory. This relation also holds for inhomogeneity averaged,effective, Hc2*(T) results… more
Date: May 8, 2006
Creator: Godeke, A.; Haken, B. ten; Kate, H.H.J. ten & Larbalestier, D.C.
Partner: UNT Libraries Government Documents Department
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