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BIGFLOW: A numerical code for simulating flow in variably saturated, heterogeneous geologic media. Theory and user`s manaual, Version 1.1

Description: This report documents BIGFLOW 1.1, a numerical code for simulating flow in variably saturated heterogeneous geologic media. It contains the underlying mathematical and numerical models, test problems, benchmarks, and applications of the BIGFLOW code. The BIGFLOW software package is composed of a simulation and an interactive data processing code (DATAFLOW). The simulation code solves linear and nonlinear porous media flow equations based on Darcy`s law, appropriately generalized to account for … more
Date: June 1, 1993
Creator: Ababou, R. & Bagtzoglou, A. C.
Partner: UNT Libraries Government Documents Department
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Development of novel copper-based sorbents for hot-gas cleanup. [Quarterly] technical report, December 1, 1993--February 28, 1994

Description: The objective of this investigation is to evaluate two novel copper-based sorbents, namely copper-chromium and copper-cerium, for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650{degree} to 850{degree}. Such high temperatures will be required for the new generation of gas turbines (inlet >750{degree}C) in Integrated Gasification Combined Cycle (IGCC) systems. The effect of pre-reduction with H{sub 2}, in the presence of H{sub 2}O on the performance … more
Date: June 1, 1994
Creator: Abbasian, J.; Hill, A. H.; Flytzani-Stephanopoulos, M. & Li, Zhijiang
Partner: UNT Libraries Government Documents Department
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Sulfur removal in advanced two-stage fluidized-bed combustion. [Quarterly] technical report, December 1, 1993--February 28, 1994

Description: The objective of this study is to obtain data on the rates of reaction between, hydrogen sulfide (H{sub 2}S) and uncalcined calcium-based sorbents under operating conditions relevant to first stage (carbonizer) of Advanced Two-Stage Pressurized Fluidized-Bed Combustors (PFBC). In these systems the CO{sub 2} partial pressure in the first stage generally exceeds the equilibrium value for calcium carbonate decomposition. Therefore, removal of sulfur compounds takes place through the reaction betwe… more
Date: June 1, 1994
Creator: Abbasian, J.; Hill, A. H.; Wangerow, J. R. & Rue, D. M.
Partner: UNT Libraries Government Documents Department
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Design considerations for the development of a space qualification Short Wavelength Imaging Fourier Transform Spectrometer (SWIFTS)

Description: This document is the final report on work performed at Sandia National Laboratories during FY 1992 and 1993 for a Laboratory Directed Research and Development (LDRD) program to look at problems associated with the design and long term operation of a short wavelength imaging Fourier Transform (FT) spectrometer for use in space. In attempts to answer two fundamental questions: is a FT spectrometer with a resolution of 1 cm{sup {minus}1} covering the silicon detector wavelength range of 0.4 to 1.1… more
Date: June 1, 1997
Creator: Abbink, R. E.
Partner: UNT Libraries Government Documents Department
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Hazardous materials in Aquatic environments of the Mississippi River basin. Quarterly project status report, 1 January 1994--30 March 1994

Description: Projects associated with this grant for studying hazardous materials in aquatic environments of the Mississippi River Basin are reviewed and goals, progress and research results are discussed. New, one-year initiation projects are described briefly.
Date: June 1, 1994
Creator: Abdelghani, A.
Partner: UNT Libraries Government Documents Department
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Fusion Neutronics Experiments and Analysis

Description: This report discusses the following topics: Tritium breeding measurements and analysis; induced radioactivity measurements and analysis; and nuclear heating measurements and analysis. (LSP)
Date: June 1, 1991
Creator: Abdou, M. A.
Partner: UNT Libraries Government Documents Department
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Numerical Studies on Soliton Propagation in the Dielectric Media by the Nonlinear Lorentz Computational Model

Description: Soliton propagation in the dielectric media has been simulated by using the nonlinear Lorentz computational model, which was recently developed to study the propagation of electromagnetic waves in a linear and a nonlinear dielectric. The model is constructed by combining a microscopic model used in the semi-classical approximation for dielectric media and the particle model developed for the plasma simulations. The carrier wave frequency is retained in the simulation so that not only the envelo… more
Date: June 1, 1994
Creator: Abe, H. & Okuda, H.
Partner: UNT Libraries Government Documents Department
open access

Numerical studies on the electromagnetic properties of the nonlinear Lorentz Computational model for the dielectric media

Description: We study linear and nonlinear properties of a new computer simulation model developed to study the propagation of electromagnetic waves in a dielectric medium in the linear and nonlinear regimes. The model is constructed by combining a microscopic model used in the semi-classical approximation for the dielectric media and the particle model developed for the plasma simulations. It is shown that the model may be useful for studying linear and nonlinear wave propagation in the dielectric media.
Date: June 1, 1994
Creator: Abe, H. & Okuda, H.
Partner: UNT Libraries Government Documents Department
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Preliminary Measurement of Prompt D+- and D*+- Meson Production and D*+- Spin Alignment in Hadronic Z0 Decays

Description: The authors have measured the production rates as a function of scaled energy x of prompt charmed pseudoscalar D{sup {+-}} and vector D*{sup {+-}} mesons in hadronic Z{sup 0} decays. The prompt signal components were isolated from the background of D mesons from B hadron decays using impact parameters of reconstructed D{sup {+-}} {yields} K{sup {minus_plus}}{pi}{sup {+-}}{pi}{sup {+-}} and D*-daughter D{sup 0} {yields} K{sup {minus}}{pi}{sup +} and D{sup 0} {yields} K{sup {minus}}{pi}{sup +}{pi… more
Date: June 1, 1997
Creator: Abe, K.; Abe, K.; Akagi, T. & Collaboration, SLD
Partner: UNT Libraries Government Documents Department
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Performance of the CRID at SLD

Description: This paper describes the performance of a large 4{pi} Cherenkov Ring Imaging Detector (CRID) in the SLD experiment at the SLC at SLAC. We compare the most recent SLD results with those obtained during the R&D period, discuss various design features, and highlight some specific lessons derived from three years of operation.
Date: June 1, 1993
Creator: Abe, K.; Antilogus, P. & Aston, D.
Partner: UNT Libraries Government Documents Department
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A Preliminary measurement of the gluon splitting rate into b\bar{b} pairs in hadronic Z0 decays

Description: We present a measurement of the rate of gluon splitting into bottom quarks, g --> b anti-b, in hadronic Z<sup>0</sup> decays collected by SLD from 1996 to 1998. The analysis was performed by looking for secondary bottom production in 4-jet events of any primary avor. A topological vertex mass technique was used to tag the two jets with the smallest angle between them as b/anti-b. We obtained a rate of g --> b anti-b per hadronic event to be (3.07 ± 0.71(stat:) ± 0.66(syst:)) × 10&sup3; (prelimi… more
Date: June 10, 1999
Creator: Abe, Toshinori
Partner: UNT Libraries Government Documents Department
open access

Oxidation rate of K-Basin spent nuclear fuel in moist air

Description: Experiments have been conducted by Pacific Northwest National Laboratory to determine the oxidation rate of damaged/corroded N-Reactor fuel material in moist air. Five SNF pieces (with regular geometrical shapes) sectioned from a damaged element stored in the K-West Basin were oxidized in flowing air containing moisture. The SNF oxidation behavior in moist air at a temperature of 198 C can best be fitted by parabolic oxidation kinetics. A linear rate equation gave the best fit to the oxidation … more
Date: June 1, 1998
Creator: Abrefah, J.; Buchanan, H. C. & Marschman, S. C.
Partner: UNT Libraries Government Documents Department
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Dry air oxidation kinetics of K-Basin spent nuclear fuel

Description: The safety and process analyses of the proposed Integrated Process Strategy (IPS) to move the N-Reactor spent nuclear fuel (SNF) stored at K-Basin to an interim storage facility require information about the oxidation behavior of the metallic uranium. Limited experiments have been performed on the oxidation reaction of SNF samples taken from an N-Reactor outer fuel element in various atmospheres. This report discusses studies on the oxidation behavior of SNF using two independent experimental s… more
Date: June 1, 1998
Creator: Abrefah, J.; Buchanan, H. C.; Gerry, W. M.; Gray, W. J. & Marschman, S. C.
Partner: UNT Libraries Government Documents Department
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The migration and entrapment of DNAPLs in physically and chemically heterogeneous porous media. 1998 annual progress report

Description: 'The migration and entrapment of dense nonaqueous phase liquids (DNAPLs) at hazardous waste sites is typically believed to be controlled by physical heterogeneities. This belief is based upon the assumption that permeability and capillary properties are determined by soil texture. These transport properties however, also depend on porous media wettability characteristics, which may vary spatially in a formation due to variations in aqueous phase chemistry, contaminant aging, and/or variations i… more
Date: June 1, 1998
Creator: Abriola, L.M. & Demond, A.H.
Partner: UNT Libraries Government Documents Department
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The Migration and Entrapment of DNAPLs in Physically and Chemically Heterogeneous Porous Media

Description: Dense nonaqueous phase liquids (DNAPLs) are common subsurface contaminants at many Department of Energy (DOE) hazardous waste sites. The migration and entrapment of DNAPLs at these sites is greatly influenced by subsurface heterogeneity, both physical and chemical. Unfortunately, the physics of DNAPL flow in chemically heterogeneous systems is poorly understood and, hence, multiphase flow simulators typically assume that subsurface soils are completely water-wet (chemically homogeneous). The pr… more
Date: June 1, 1999
Creator: Abriola, Linda M.; Demond, Avery H. & Glass, Robert
Partner: UNT Libraries Government Documents Department
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Quantitative non-destructive evaluation of high-temperature superconducting materials

Description: Even though the currently intensive research efforts on high- temperature superconducting materials have not yet converged on a well specified practical material, the indications are that such a material may be quite brittle, anisotropic, and may contain many flaws such as microcracks and voids at grain boundaries. Consequently, practical applications of high temperature superconducting materials will require a very careful strength analysis based on fracture mechanics considerations. Because o… more
Date: June 14, 1991
Creator: Achenbach, J. D.
Partner: UNT Libraries Government Documents Department
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Quantitative non-destructive evaluation of high-temperature superconducting materials. Progress report, September 1, 1990--August 31, 1991

Description: Even though the currently intensive research efforts on high- temperature superconducting materials have not yet converged on a well specified practical material, the indications are that such a material may be quite brittle, anisotropic, and may contain many flaws such as microcracks and voids at grain boundaries. Consequently, practical applications of high temperature superconducting materials will require a very careful strength analysis based on fracture mechanics considerations. Because o… more
Date: June 14, 1991
Creator: Achenbach, J. D.
Partner: UNT Libraries Government Documents Department
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Education Vouchers: The Constitutional Standards

Description: This report sketches the constitutional standards that apply to public aid to sectarian schools and especially to programs of indirect assistance such as education vouchers.
Date: June 11, 1998
Creator: Ackerman, David M.
Partner: UNT Libraries Government Documents Department
open access

Education Vouchers: The Constitutional Standards

Description: The Court’s decisions permit a limited degree of public aid to be provided directly and a broader range of assistance indirectly. This report sketches the constitutional standards that apply to public aid to sectarian schools and especially to programs of indirect assistance such as education vouchers. It also summarizes recent significant state court decisions involving vouchers.
Date: June 11, 1998
Creator: Ackerman, David M.
Partner: UNT Libraries Government Documents Department
open access

The Religious Freedom Restoration Act: Its Rise, Fall, and Current Status

Description: This report briefly summarizes Employment Division, Oregon Department of Human Resources v. Smith, the legislative history of the Religious Freedom Restoration Act (RFRA), the Supreme Court's decision in City of Boerne, Texas v. Flores, and RFRA's current legal status, and notes the introduction of the Religious Liberty Protection Act (RLPA).
Date: June 25, 1998
Creator: Ackerman, David M.
Partner: UNT Libraries Government Documents Department
open access

Biological Conversion of Synthesis Gas

Description: Overall mass transfer coefficients for CO have been determined in a continuous stirred-tank reactor at agitation rates of 300--700 rpm using a biological system with the photosynthetic bacterium Rhodospirillum rubrum. A non-steady state approach was employed in order to separate mass transfer and kinetic limited regions of the fermentation. As a result, a kinetic model could be developed for specific CO uptake by the culture including the apparent CO inhibition. The maximum specific CO uptake r… more
Date: June 30, 1992
Creator: Ackerson, M. D.; Clausen, E. C. & Gaddy, J. L.
Partner: UNT Libraries Government Documents Department
open access

Biological Conversion of Synthesis Gas. Project Status Report, April 1, 1992--June 30, 1992

Description: Overall mass transfer coefficients for CO have been determined in a continuous stirred-tank reactor at agitation rates of 300--700 rpm using a biological system with the photosynthetic bacterium Rhodospirillum rubrum. A non-steady state approach was employed in order to separate mass transfer and kinetic limited regions of the fermentation. As a result, a kinetic model could be developed for specific CO uptake by the culture including the apparent CO inhibition. The maximum specific CO uptake r… more
Date: June 30, 1992
Creator: Ackerson, M. D.; Clausen, E. C. & Gaddy, J. L.
Partner: UNT Libraries Government Documents Department
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