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Aerodynamic Design of Heavy Vehicles Reporting Period January 15, 2004 through April 15, 2004

Description: Listed are summaries of the activities and accomplishments during this second-quarter reporting period for each of the consortium participants. The following are some highlights for this reporting period: (1) Experiments and computations guide conceptual designs for reduction of drag due to tractor-trailer gap flow (splitter plate), trailer underbody (wedges), and base drag (base-flap add-ons). (2) Steady and unsteady RANS simulations for the GTS geometry are being finalized for development of … more
Date: April 13, 2004
Creator: Leonard, A.; Chatelain, P.; Heineck, J.; Browand, F.; Mehta, R.; Ortega, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Neutrons and Granite: Transport and Activation

Description: In typical ground materials, both energy deposition and radionuclide production by energetic neutrons vary with the incident particle energy in a non-monotonic way. We describe the overall balance of nuclear reactions involving neutrons impinging on granite to demonstrate these energy-dependencies. While granite is a useful surrogate for a broad range of soil and rock types, the incorporation of small amounts of water (hydrogen) does alter the balance of nuclear reactions.
Date: April 13, 2004
Creator: Bedrossian, P J
Partner: UNT Libraries Government Documents Department
open access

A Measurement of the Top Quark Mass with the D0 Detector at s**(1/2) = 1.96-TeV using the Matrix Element Method

Description: Using a data set of 158 and 169 pb{sup -1} of D0 Run-II data in the electron and muon plus jets channel, respectively, the top quark mass has been measured using the Matrix Element Method. The method and its implementation are described. Its performance is studied in Monte Carlo using ensemble tests and the method is applied to the Moriond 2004 data set.
Date: April 1, 2004
Creator: Kroeninger, Kevin Alexander
Partner: UNT Libraries Government Documents Department
open access

3D Computations and Experiments

Description: This project consists of two activities. Task A, Simulations and Measurements, combines all the material model development and associated numerical work with the materials-oriented experimental activities. The goal of this effort is to provide an improved understanding of dynamic material properties and to provide accurate numerical representations of those properties for use in analysis codes. Task B, ALE3D Development, involves general development activities in the ALE3D code with the focus o… more
Date: April 5, 2004
Creator: Couch, R; Faux, D; Goto, D & Nikkel, D
Partner: UNT Libraries Government Documents Department
open access

Precision Micron Hole Drilling using a Frequency Doubled, Diode Pumped Solid State Laser

Description: This work represents the second phase of a program to demonstrate precision laser drilling with minimal Heat Affected Zone. The technique uses a Diode Pumped Solid State Laser with two wavelengths and two modes of operation. The fundamental mode of the DPSSL at 1.06 microns is used to drill a hole with a diameter of a fraction of a millimeter diameter in a millimeter thick substrate quickly, but with low precision. This hole is then machined to precision dimensions using the second harmonic of … more
Date: April 21, 2004
Creator: Friedman, H W & Pierce, E L
Partner: UNT Libraries Government Documents Department
open access

Adaptive 4-8 Texture Hierarchies

Description: No Description Available.
Date: April 14, 2004
Creator: Hwa, L M; Duchaineau, M A & Joy, K I
Partner: UNT Libraries Government Documents Department
open access

Direct Carbon Fuel Cells: Assessment of their Potential as Solid Carbon Fuel Based Power Generation Systems

Description: Small-scale experimental work at Lawrence Livermore National Laboratory (LLNL) has confirmed that a direct carbon fuel cell (DCFC) containing a molten carbonate electrolyte completely reacts solid elemental carbon with atmospheric oxygen contained in ambient air at a temperature of 650-800 C. The efficiency of conversion of the chemical energy in the fuel to DC electricity is 75-80% and is a result of zero entropy change for this reaction and the fixed chemical potentials of C and CO{sub 2}. Th… more
Date: April 23, 2004
Creator: Wolk, R
Partner: UNT Libraries Government Documents Department
open access

Post-Closure Groundwater Monitoring Plan for the 1324-N Surface Impoundment and 1324-NA Percolation Pond

Description: The 1324-N Surface Impoundment and the 1324-NA Percolation Pond, located in the 100-N Area of the Hanford Site, are regulated under the Resource Consevation and Recovery Act (RCRA). Surface and underground features of the facilities have been removed and laboratory analyses showed that soil met the closure performance standards. These sites have been backfilled and revegetated.
Date: April 2, 2004
Creator: Hartman, Mary J.
Partner: UNT Libraries Government Documents Department
open access

Calculation of Phonon Density of States for Alpha-U

Description: Phonon density of states for {alpha}-U was calculated with the linear response theory and the RSPFLAPW (fully relativistic full potential spin-polarized linearized-augmented-plane-wave) method. It has been used for studying the temperature dependence of the specific heat of uranium. It was shown that the details of the phonon DOS are not very important for the specific heat, and practically the same results can be obtained with Debye model.
Date: April 1, 2004
Creator: Kutepov, A
Partner: UNT Libraries Government Documents Department
open access

Distribution of incoherent space - Charge tune shift of a bi-Gaussian beam

Description: The incoherent space-charge self-force tune shift of a bi-Gaussian coasting beam is revisited. The distribution density of the incoherent horizontal or vertical space-charge tune shift is computed numerically using a statistical method. Analytic approach has also been made with approximation. The results show a broad peak centered about 0.633 with a rms spread 0.168 of the linear space-charge tune shift.
Date: April 1, 2004
Creator: Ng, K. Y.
Partner: UNT Libraries Government Documents Department
open access

Quantifying the effects of limited CO2 fertilization on future climate

Description: The response of the land biosphere to the ongoing increase in atmospheric CO{sub 2} is not fully understood. To evaluate the approximate upper and lower limits of land sequestration of carbon, we performed simulations using a comprehensive carbon-climate model. In one case the land biosphere is vigorously fertilized by added CO{sub 2} and sequesters carbon throughout the 21st century. In a second case, CO{sub 2} fertilization saturates in year 2000; in this case the land becomes an additional s… more
Date: April 6, 2004
Creator: Erickson, D.; Govindasamy, B.; Caldeira, K.; Mirin, A.; Thompson, S. L.; Delire, C. et al.
Partner: UNT Libraries Government Documents Department
open access

Resolving Nuclear Reactor Lifetime Extension Questions: A Combined Multiscale Modeling and Positron Characterization approach

Description: The objective of this work is to determine the chemical composition of nanometer precipitates responsible for irradiation hardening and embrittlement of reactor pressure vessel steels, which threaten to limit the operating lifetime of nuclear power plants worldwide. The scientific approach incorporates computational multiscale modeling of radiation damage and microstructural evolution in Fe-Cu-Ni-Mn alloys, and experimental characterization by positron annihilation spectroscopy and small angle … more
Date: April 6, 2004
Creator: Wirth, B.; Asoka-Kumar, P.; Denison, A.; Glade, S.; Howell, R.; Marian, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Pacific Northwest National Laboratory Institutional Plan FY 2004-2008

Description: This Institutional Plan for FY 2004-2008 is the principal annual planning document submitted to the Department of Energy's Office of Science by Pacific Northwest National Laboratory in Richland, Washington. This plan describes the Laboratory's mission, roles, and technical capabilities in support of Department of Energy priorities, missions, and plans. It also describes the Laboratory strategic plan, key planning assumptions, major research initiatives, and program strategy for fundamental scie… more
Date: April 15, 2004
Creator: Quadrel, Marilyn J.
Partner: UNT Libraries Government Documents Department
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Study of the Reactions Controlling the Mobility of Uranium in Ground and Surface Water Systems in Contact with Apatite

Description: The objective of this project was to define the mechanisms, equilibria, kinetics, and extent of sorption of aqueous uranium onto hydroxyapatite (Ca{sub 5}(PO{sub 4}){sub 3}(OH)) for a range of pH, ionic strength, aqueous uranium concentration, dissolved carbon/air CO{sub 2}, and mineral surface area. We conducted chemical modeling, batch and flow-through experiments, chemical analysis, x-ray absorption and diffraction measurement, and electron microscopy. Our motivation was the need to immobili… more
Date: April 22, 2004
Creator: Taffet, M
Partner: UNT Libraries Government Documents Department
open access

Atmospheric Data Package for the 2004 Composite Analysis

Description: The purpose of this data package is to summarize our conceptual understanding of atmospheric transport and deposition, describe how this understanding will be simplified for numerical simulation as part of the 2004 Composite Analysis (i.e., implementation model), and finally to provide the input parameters needed for the simulations.
Date: April 30, 2004
Creator: Napier, Bruce A. & Ramsdell, James V.
Partner: UNT Libraries Government Documents Department
open access

Flash X-Ray (FXR) Accelerator Optimization - Beam-induced Voltage Simulation and TDR Measurements

Description: Lawrence Livermore National Laboratory (LLNL) is evaluating design alternatives to improve the voltage regulation in our Flash X-Ray (FXR) accelerator cell and pulse-power system. The goal is to create a more mono-energetic electron beam that will create an x-ray source with a smaller spot-size. Studying the interaction of the beam and accelerator cell will generate improved designs for high-current accelerators at Livermore and elsewhere. When an electron beam crosses the energized gap of an a… more
Date: April 7, 2004
Creator: Ong, M. M. & Vogtlin, G. E.
Partner: UNT Libraries Government Documents Department
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Characterization of Vadose Zone Sediments Below the TX Tank Farm: Probe Holes C3830, C3831, C3832 and 299-W10-27

Description: Pacific Northwest National Laboratory performed detailed analyses on vadose zone sediments from within Waste Management Area T-TX-TY. This report contains all the geologic, geochemical, and selected physical characterization data collected on vadose zone sediment recovered from three probe holes (C3830, C3831, and C3832) in the TX Tank Farm, and from borehole 299-W-10-27. Sediments from borehole 299-W-10-27 are considered to be uncontaminated sediments that can be compared with contaminated sed… more
Date: April 1, 2004
Creator: Serne, R JEFFREY.; Bjornstad, Bruce N.; Horton, Duane G.; Lanigan, David C.; Lindenmeier, Clark W.; Lindberg, Michael J. et al.
Partner: UNT Libraries Government Documents Department
open access

Atlas de Recursos Eólicos del Estado de Oaxaca

Description: The Oaxaca Wind Resource Atlas, produced by the National Renewable Energy Laboratory's (NREL's) wind resource group, is the result of an extensive mapping study for the Mexican State of Oaxaca. This atlas identifies the wind characteristics and distribution of the wind resource in Oaxaca. The detailed wind resource maps and other information contained in the atlas facilitate the identification of prospective areas for use of wind energy technologies, both for utility-scale power generation and … more
Date: April 1, 2004
Creator: Elliott, D.; Schwartz, M.; Scott, G.; Haymes, S.; Heimiller, D. & George, R.
Partner: UNT Libraries Government Documents Department
open access

Hanford Site Groundwater Monitoring for Fiscal Year 2003

Description: This report presents the results of groundwater and vadose zone monitoring and remediation for fiscal year 2003 (October 2002 through September 2003) on the U.S. Department of Energy's Hanford Site, Washington. The most extensive contaminant plumes in groundwater are tritium, iodine-129, and nitrate, which all had multiple sources and are very mobile in groundwater. The largest portions of these plumes are migrating from the central Hanford Site to the southeast, toward the Columbia River. Conc… more
Date: April 12, 2004
Creator: Hartman, Mary J.; Morasch, Launa F. & Webber, William D.
Partner: UNT Libraries Government Documents Department
open access

Safety Report - Experiments 999 and 891 Muon Spin Relaxation in Pu and Pu-based Heavy Fermion Materials

Description: Experiment E999 proposes to carry out conventional muon spin relaxation ({mu}SR) measurements on solid samples of plutonium and plutonium alloys. Experiment 891 will be involved with {mu}SR experiments on PuCoGa{sub 5} and related Pu-based superconductors. Other than a dedicated cryostat to be provided by Los Alamos and a pumping station provided by Livermore, the experiments will use existing {mu}SR User Facility spectrometers and associated equipment such as detectors and electronics. The mai… more
Date: April 23, 2004
Creator: Fluss, M; Heffner, R & Morris, G
Partner: UNT Libraries Government Documents Department
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