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Interfacial behavior of polymer electrolytes

Description: Evidence is presented concerning the effect of surfaces on the segmental motion of PEO-based polymer electrolytes in lithium batteries. For dry systems with no moisture the effect of surfaces of nano-particle fillers is to inhibit the segmental motion and to reduce the lithium ion transport. These effects also occur at the surfaces in composite electrodes that contain considerable quantities of carbon black nano-particles for electronic connection. The problem of reduced polymer mobility is com… more
Date: June 3, 2003
Creator: Kerr, John; Kerr, John B.; Han, Yong Bong; Liu, Gao; Reeder, Craig; Xie, Jiangbing et al.
Partner: UNT Libraries Government Documents Department
open access

Linking reaction, transport, and hydrological parameters inunsaturated fractured rock: toughreact implementation andapplication

Description: Modeling coupled water-gas-rock interactions in unsaturated fractured rock requires conceptual and numerical model considerations beyond those developed for saturated porous media. This paper focuses on the integration of the geological and hydrological parameters into the calculation of reactive-transport parameters and the feedback of mineral precipitation/dissolution to flow and transport. These basic relations have been implemented in the reactive transport code TOUGHREACT (Xu et al., 2003)… more
Date: May 15, 2003
Creator: Sonnenthal, Eric; Spycher, Nicolas & Xu, Tianfu
Partner: UNT Libraries Government Documents Department
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The effect of CO2(aq), Al(aq) and temperature on feldspar dissolution

Description: The authors measured labradorite (Ca{sub 0.6}Na{sub 0.4}Al{sub 1.6}Si{sub 2.4}O{sub 8}) dissolution rates using a mixed flow reactor from 30 to 130 C as a function of CO{sub 2} (3 x 10{sup -3} and 0.6 M), and aluminum (10{sup -6} to 10{sup -3}M) at pH 3.2. Over these conditions, labradorite dissolution can be described with a single rate expression that accounts for observed increases in dissolution rate with temperature and decreases in dissolution rate with dissolved aluminum: Rate{sub Si} (m… more
Date: October 14, 2003
Creator: Carroll, S. & Knauss, K.
Partner: UNT Libraries Government Documents Department
open access

Advanced Interactive Facades - Critical Elements for Future GreenBuildings?

Description: Building designers and owners have always been fascinated with the extensive use of glass in building envelopes. Today the highly glazed facade has almost become an iconic element for a 'green building' that provides daylighting and a visual connection with the natural environment. Even before the current interest in green buildings there was no shortage of highly glazed building designs. But many of these buildings either rejected sunlight, and some associated daylight and view with highly ref… more
Date: November 1, 2003
Creator: Selkowitz, Stephen; Aschehoug, Oyvind & Lee, Eleanor S.
Partner: UNT Libraries Government Documents Department
open access

Materials Science at the Extremes of Pressure and Strain Rate

Description: Solid state experiments at very high pressures and strain rates are possible on high power laser facilities, albeit over brief intervals of time and spatial small scales. A new shockless drive has been developed on the Omega laser. VISAR measurements establish the high strain rates, 10{sup 7}-10{sup 8} s{sup -1}. Solid-state strength is inferred using the Rayleigh-Taylor instability as a ''diagnostic''. Temperature and compression in polycrystalline samples can be deduced from EXAFS measurement… more
Date: August 20, 2003
Creator: Remington, B. A.; Cavallo, R. M.; Edwards, M. J.; Lasinski, B. F.; Lorenz, K. T.; Lorenzana, H. E. et al.
Partner: UNT Libraries Government Documents Department
open access

Multi-fluid code simulations including anomalous non-diffusive transport of plasma and impurities in the tokamak SOL

Description: Fast intermittent transport has been observed in the scrape-off layer (SOL) of major tokamaks including Alcator C-Mod, DIII-D, and NSTX. This kind of transport is not diffusive but rather convective. It strongly increases plasma flux to the chamber walls and enhances the recycling of neutral particles in the main chamber. We discuss anomalous cross-field convection (ACFC) model for impurity and main plasma ions and its relation to intermittent transport events, i.e. plasma density blobs and hol… more
Date: November 25, 2003
Creator: Pigarov, A. Yu; West, W. P.; Soukhanovskii, V.; Rognlien, T. D.; Maingi, R.; Lipschultz, B. et al.
Partner: UNT Libraries Government Documents Department
open access

Progress in Horizontal and Slant-Path Imaging Speckle Imaging

Description: The difficulty in terrestrial imaging over long horizontal or slant paths is that atmospheric aberrations and distortions reduce the resolution and contrast in images recorded at high resolution. This paper will describe the problem of horizontal-path imaging, briefly cover various methods for imaging over horizontal paths and then describe the speckle imaging method actively being pursued at LLNL. We will review some closer range (1-3 km range) imagery of people we have already published, as w… more
Date: January 30, 2003
Creator: Carrano, C J
Partner: UNT Libraries Government Documents Department
open access

Design and Performance of the Van Geet Off-Grid Home: Preprint

Description: The Van Geet home near Denver, Colorado, demonstrates the successful integration of energy conservation measures and renewable energy supply in a beautiful, comfortable, energy-efficient, 295-m2 (3,176-ft2) off-grid home in a cold, sunny climate. Features include a tight envelope, energy-efficient appliances, passive solar heating (direct gain and Trombe wall), natural cooling, solar hot water, and photovoltaics. In addition to describing this house and its performance, this paper describes the… more
Date: January 1, 2003
Creator: Barley, C. D.; Torcellini, P. & Van Geet, O.
Partner: UNT Libraries Government Documents Department
open access

Linear Model for Non Isosceles Absorbers.

Description: Previous analyses have assumed that wedge absorbers are triangularly shaped with equal angles for the two faces. In this case, to linear order, the energy loss depends only on the position in the direction of the face tilt, and is independent of the incoming angle. One can instead construct an absorber with entrance and exit faces facing rather general directions. In this case, the energy loss can depend on both the position and the angle of the particle in question. This paper demonstrates tha… more
Date: May 12, 2003
Creator: Berg, J. S.
Partner: UNT Libraries Government Documents Department
open access

Effect of Ethanol and Methyl-tert-Butyl Ether on Monoaromatic Hydrocarbon Biodegradation: Response Variability for Different Aquifer Materials Under Various Electron-Accepting Conditions

Description: Aquifer microcosms were used to determine how ethanol and methyl-tert-butyl ether (MtBE) affect monoaromatic hydrocarbon degradation under different electron-accepting conditions commonly found in contaminated sites experiencing natural attenuation. Response variability was investigated by using aquifer material from four sites with different exposure history. The lag phase prior to BTEX (benzene, toluene, ethylbenzene, and xylenes) and ethanol degradation was typically shorter in microcosms wi… more
Date: October 6, 2003
Creator: Ruiz-Aguilar, G L; Fernandez-Sanchez, J M; Kane, S R; Kim, D & Alvarez, P J
Partner: UNT Libraries Government Documents Department
open access

Geophysical Models for Nuclear Explosion Monitoring

Description: Geophysical models are increasingly recognized as an important component of regional calibrations for seismic monitoring. The models can be used to predict geophysical measurements, such as body wave travel times, and can be derived from direct regional studies or even by geophysical analogy. While empirical measurements of these geophysical parameters might be preferred, in aseismic regions or regions without seismic stations, this data might not exist. In these cases, models represent a 'best… more
Date: July 16, 2003
Creator: Pasyanos, M E; Walter, W R & Flanagan, M
Partner: UNT Libraries Government Documents Department
open access

Analytic ICF Hohlraum Energetics

Description: We apply recent analytic solutions to the radiation diffusion equation to problems of interest for ICF hohlraums. The solutions provide quantitative values for absorbed energy which are of use for generating a desired radiation temperature vs. time within the hohlraum. Comparison of supersonic and subsonic solutions (heat front velocity faster or slower, respectively, than the speed of sound in the x-ray heated material) suggests that there may be some advantage in using high Z metallic foams a… more
Date: August 27, 2003
Creator: Rosen, M D & Hammer, J
Partner: UNT Libraries Government Documents Department
open access

A Source-to-Source Architecture for User-Defined Optimizations

Description: The performance of object-oriented applications often suffers from the inefficient use of high-level abstractions provided by underlying libraries. Since these library abstractions are user-defined and not part of the programming language itself only limited information on their high-level semantics can be leveraged through program analysis by the compiler and thus most often no appropriate high-level optimizations are performed. In this paper we outline an approach based on source-to-source tr… more
Date: February 6, 2003
Creator: Schordan, M & Quinlan, D
Partner: UNT Libraries Government Documents Department
open access

Astronomy Applications of Adaptive Optics at Lawrence Livermore National Laboratory

Description: Astronomical applications of adaptive optics at Lawrence Livermore National Laboratory (LLNL) has a history that extends from 1984. The program started with the Lick Observatory Adaptive Optics system and has progressed through the years to lever-larger telescopes: Keck, and now the proposed CELT (California Extremely Large Telescope) 30m telescope. LLNL AO continues to be at the forefront of AO development and science.
Date: April 23, 2003
Creator: Bauman, B J & Gavel, D T
Partner: UNT Libraries Government Documents Department
open access

Physical evidence for dark energy

Description: The authors present measurements of the angular cross-correlation between luminous red galaxies from the Sloan Digital Sky Survey and the cosmic microwave background temperature maps from the Wilkinson Microwave Anisotropy Probe. They find a statistically significant achromatic positive correlation between these two data sets, which is consistent with the expected signal from the late Integrated Sachs-Wolfe (ISW) effect. they do not detect any anti-correlation on small angular scales as would b… more
Date: July 1, 2003
Creator: Scranton, Ryan; Connolly, Andrew J.; Nichol, Robert C.; Stebbins, Albert; Szapudi, Istvan; Eisenstein, Daniel J. et al.
Partner: UNT Libraries Government Documents Department
open access

ACTION AND PHASE ANALYSIS TO DETERMINE SEXTUPOLE ERRORS IN RHIC AND THE SPS.

Description: Success in the application of the action and phase analysis to find linear errors at RHIC Interaction Regions [1] has encouraged the creation of a technique based on the action and phase analysis to find non linear errors. In this paper we show the first attempt to measure the sextupole components at RHIC interaction regions using the action and phase method. Experiments done by intentionally activating sextupoles in RHIC and in SPS [2] will also be analyzed with this method. First results have… more
Date: May 12, 2003
Creator: Cardona, J.; Peggs, S.; Satogata, T. & Tomas, R.
Partner: UNT Libraries Government Documents Department
open access

Thermo-Gas-Dynamic Model of Afterburning in Explosions

Description: A theoretical model of afterburning in explosions created by turbulent mixing of the detonation products from fuel-rich charges with air is described. It contains three key elements: (i) a thermodynamic-equilibrium description of the fluids (fuel, air, and products), (ii) a multi-component gas-dynamic treatment of the flow field, and (iii) a sub-grid model of molecular processes of mixing, combustion and equilibration.
Date: July 27, 2003
Creator: Kuhl, A L; Ferguson, R E & Bell, J B
Partner: UNT Libraries Government Documents Department
open access

Tilted Thick-Disk Accretion onto a Kerr Black Hole

Description: We present the first results from fully general relativistic numerical studies of thick-disk accretion onto a rapidly-rotating (Kerr) black hole with a spin axis that is tilted (not aligned) with the angular momentum vector of the disk. We initialize the problem with the solution for an aligned, constant angular momentum, accreting thick disk around a black hole with spin a/M = J/M{sup 2} = +0.9 (prograde disk). The black hole is then instantaneously tilted, through a change in the metric, by a… more
Date: December 12, 2003
Creator: Fragile, P C & Anninos, P
Partner: UNT Libraries Government Documents Department
open access

Delamination Failure Investigation for Out-Of-Plane Loading in Laminates

Description: In contrast to failure approaches at the lamina level or the micromechanics level the present work concerns failure characterization at the laminate level. Specifically, attention is given to the ultimate failure characterization for quasi-isotropic laminates. This is in further contrast to the commonly used approaches for initial damage or progressive damage. It is shown that the analytical failure forms decompose into two modes, one for out of plane, delamination type failure and one for in p… more
Date: March 26, 2003
Creator: Christensen, R M & DeTeresa, S J
Partner: UNT Libraries Government Documents Department
open access

Microstructure of Surface Layers in Cu(In,Ga)Se2 Thin Films

Description: In most Cu(In,Ga)Se2 thin films used for solar cells, there usually exist interfaces lying about 0.1 to 0.2 m below the surfaces. We report on a convergent-beam electron diffraction and energy-dispersive X-ray spectroscopy study of the microstructure and chemical composition of the surface region in Cu(In,Ga)Se2 thin films. We find that the surface region and the bulk are structurally similar, with no ordered defect chalcopyrite structure observed. However, their composition is slightly differe… more
Date: May 1, 2003
Creator: Yan, Y.; Jones, K. M.; AbuShama, J.; Young, M.; Asher, S.; Al-Jassim, M. M. et al.
Partner: UNT Libraries Government Documents Department
open access

ELECTRON CLOUD AND PRESSURE RISE SIMULATIONS FOR RHIC.

Description: Beam induced electron multipacting may be among the main reasons for the vacuum pressure rise when circulating high intensity ion and proton beams in RHIC. Latest simulation results are benchmarked with recent experimental observations for RHIC, and compared to other general computer codes. The influence of the electron multipacting to the vacuum properties is also discussed.
Date: May 12, 2003
Creator: IRISO-ARIZ,U. BLASKIEWICZ,M. DREES,A. FISCHER,W. PEGGS,S. TRBOJEVIC,D.
Partner: UNT Libraries Government Documents Department
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