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Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

Description: The objective of this project is to provide the fundamental information on the mechanisms of bacterial leaching of pyrite. The knowledge of how bacterial leaching of pyrite functions is essential for design and development of a technology for coal cleaning with bacteria. The features of major electrochemical techniques will be examined to find out if any of them can provide a diagnostic information on the mechanisms of related reactions.
Date: January 1, 1992
Creator: Pesic, B.
Partner: UNT Libraries Government Documents Department
open access

Redox reactions involving chromium, plutonium, and manganese in soils

Description: Plutonium speciation in soils is discussed. Chromium was selected as a model for studying soil Pu. Similarities between Cr and Pu are pointed out, and a hypotheses concerning Pu speciation in soils is presented. Findings from Cr oxidation studies that may be relevant to the problem of Pu oxidation in soils are discussed. (JGB)
Date: January 1, 1979
Creator: Amacher, M.C. & Baker, D.E.
Partner: UNT Libraries Government Documents Department
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Development and process evaluation of improved Fischer-Tropsch slurry catalysts

Description: The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.
Date: January 1, 1987
Creator: Withers, H.P. (Air Products and Chemicals, Inc., Allentown, PA (United States)); Bukur, D.B. & Rosynek, M.P. (Texas A and M Univ., College Station, TX (United States))
Partner: UNT Libraries Government Documents Department
open access

Development of a computer program for reactor core thermal hydraulics: finite differencing in a 3-D staggered mesh suitable for irregular boundary applications

Description: A formulation utilizing a finite difference scheme for the direct numerical simulation of time varying two-phase flow problems in three space dimensions with irregular boundary geometry is presented. The formulation of such problems introduces a complicated set of coupled non-linear partial differential equations for the conservation of mass, momentum, energy, appropriate constitutive equations, and equations of state coupling the two phases. Discretization of the partial differential equations… more
Date: unknown
Creator: Sha, W.T.
Partner: UNT Libraries Government Documents Department
open access

NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts

Description: Copper and cobalt are the key elements in syngas conversion catalyst systems used for higher alcohol synthesis. Their proximity and synergy sensitively control the selectivity and efficiency of the process. It is believed that their outer electronic charge distribution which is responsible for their electrical and magnetic properties might be governing their catalytic properties also. To examine the correlation between catalytic and magnetic properties, a series of copper cobalt catalysts (Co/C… more
Date: January 14, 1991
Partner: UNT Libraries Government Documents Department
open access

Source-jerk analysis using a semi-explicit inverse kinetic technique

Description: A method is proposed for measuring the effective reproduction factor, k, in subcritical systems. The method uses the transient response of a subcritical system to the sudden removal of an extraneous neutron source (i.e., a source jerk). The response is analyzed using an inverse kinetic technique that least-squares fits the exact analytical solution corresponding to a source-jerk transient as derived from the point-reactor model. It has been found that the technique can provide an accurate means… more
Date: January 1, 1985
Creator: Spriggs, G.D. & Pederson, R.A.
Partner: UNT Libraries Government Documents Department
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Biological Production of Ethanol From Coal

Description: The fermentation pH has been observed to be the key parameter affecting the ratio of ethanol to acetate produced by Clostridium ljungdahlii. The effects of controlled pH on cell growth and product formation by C. ljungdahlii were measured. It was found that cell concentration and acetate concentration increased with pH, while the ethanol concentration was highest at the lower pH. The molar product ratio of ethanol to acetate was 0.74 at pH 4.0, 0.39 at pH 4.5 and 0.12 at pH 5.0. Future experime… more
Date: January 1, 1990
Partner: UNT Libraries Government Documents Department
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Biological Production of Ethanol From Coal

Description: Research is continuing in an attempt to increase both the ethanol concentration and product ratio using C. ljungdahlii. The purpose of this report is to present data utilizing a medium prepared especially for C. ljungdahlii. Medium development studies are presented, as well as reactor studies with the new medium in batch reactors. CSTRs and CSTRs with cell recycle. The use of this new medium has resulted in significant improvements in cell concentration, ethanol concentration and product ratio.
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department
open access

Successive collision calculation of resonance absorption

Description: The successive collision method for calculating resonance absorption solves numerically the neutron slowing down problem in reactor lattices. A discrete energy mesh is used with cross sections taken from a Monte Carlo library. The major physical approximations used are isotropic scattering in both the laboratory and center-of-mass systems. This procedure is intended for day-to-day analysis calculations and has been incorporated into the current version of MUFT. The calculational model used for … more
Date: July 1, 1980
Creator: Schmidt, E. & Eisenhart, L.D.
Partner: UNT Libraries Government Documents Department
open access

Synergistic capture mechanisms for alkali and sulfur species from combustion

Description: This report presents work done on a laboratory combustor in an attempt to identify mechanisms that govern the simultaneous capture of alkali and sulfur species using sorbent injection techniques. The mechanisms of capture fall into two broad categories i.e. Physical transport of alkali species (in vapor or condensed phase) to the sorbent surface and surface reaction between the alkali species and the sorbents. Water solubility, though not specific, has been used to get an indication of relative… more
Date: April 23, 1992
Creator: Peterson, T.W.; Shadman, F.; Wendt, J.O.L. & Mwabe, P.O.
Partner: UNT Libraries Government Documents Department
open access

Geothermal waste treatment biotechnology: Progress and advantages to the utilities

Description: Development of biotechnology for treatment of geothermal residual waste is aimed at the application of low-cost biochemical processes for the surface treatment and disposal of residual geothermal sludges. These processes, in addition to the lowering of disposal cost, are designed to be environmentally acceptable. Recent studies at Brookhaven National Laboratory (BNL) have shown that optimization of several process variables results in fast rates (<24h) of metal removal from residual sludges at … more
Date: March 1, 1992
Creator: Premuzic, E.T.; Lin, M.S. & Jin, J.
Partner: UNT Libraries Government Documents Department
open access

Statistical fluctuations in heavy-ion collisions

Description: The relevance of the statistical equilibrium limit to the description of substantially relaxed degrees of freedom is discussed. Fluctuations are considered specifically in the following processes: the correlation between entrance-channel angular momentum and exit-channel kinetic energy; the sharing of the dissipated kinetic energy between the two fragments; the magnitude and the alignment of the fragment angular momentum including the effect of shell structure. It is found that statistical fluc… more
Date: February 1, 1982
Creator: Moretto, Luciano G.
Partner: UNT Libraries Government Documents Department
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Theory of chemical kinetics. Progress report, May 1, 1977--January 15, 1978. [Massachusetts Inst. of Tech. , Cambridge]

Description: Recent work on Franck--Condon factors in studies of the dynamics of chemical reactions is related; emphasis was on simple chemical rearrangement reactions. Other work concerned collision-free unimolecular decomposition of large molecules at a given total energy, equations of motion for simple quantum systems that are strongly driven by an external field and are modulated stochastically by a coupling to a bath, and the efficiency of rate processes in irreversible chemical reactions. This report … more
Date: unknown
Creator: Ross, J.
Partner: UNT Libraries Government Documents Department
open access

Oxidation/gasification of carbon residue on retorted oil shale. Final report

Description: Studies of the oxidation and gasification of oil shale char were extended to an investigation of the effects of mineral catalysis. Six shales with differing mineral compositions were studied, including samples from the saline zone in the Western Colorado and from the Antrim shales of Michigan. Oxidation kinetics data, corrected for mass transfer effects, were compared for all six samples. A high assay shale from Utah and a sample from the saline zone were found to have the highest oxidation rat… more
Date: January 16, 1984
Creator: Thomson, W. J.
Partner: UNT Libraries Government Documents Department
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Massive sulfide deposits and hydrothermal solutions: incremental reaction modeling of mineral precipitation and sulfur isotopic evolution

Description: Incremental reaction path modeling of chemical and sulfur isotopic reactions occurring in active hydrothermal vents on the seafloor, in combination with chemical and petrographic data from sulfide samples from the seafloor and massive sulfide ore deposits, allows a detailed examination of the processes involved. This paper presents theoretical models of reactions of two types: (1) adiabatic mixing between hydrothermal solution and seawater, and (2) reaction of hydrothermal solution with sulfide… more
Date: January 1, 1986
Creator: Janecky, D.R.
Partner: UNT Libraries Government Documents Department
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Lecture notes for criticality safety

Description: These lecture notes for criticality safety are prepared for the training of Department of Energy supervisory, project management, and administrative staff. Technical training and basic mathematics are assumed. The notes are designed for a two-day course, taught by two lecturers. Video tapes may be used at the options of the instructors. The notes provide all the materials that are necessary but outside reading will assist in the fullest understanding. The course begins with a nuclear physics ov… more
Date: March 1, 1992
Creator: Fullwood, R.
Partner: UNT Libraries Government Documents Department
open access

Complex temporal and spatial patterns in nonequilibrium systems

Description: Dynamical systems methods are being developed and used to characterize the formation and evolution of temporal and spatial patterns in systems maintained far from equilibrium. In particular, experiments and analyses are considering electrodeposition of fractal metallic clusters, pattern formation in reaction-diffusion systems, and the primary instabilities of some fluid flows. Novel reactors have been developed to search for chemical patterns (spatial variations in the chemical composition), an… more
Date: September 1, 1991
Creator: Swinney, H. L.
Partner: UNT Libraries Government Documents Department
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Conversion rates in power plant plumes based on filter pack data. Part I. Coal-fired Cumberland plume

Description: The TVA Cumberland Steam Plant plume was monitored during the August 1978 Tennessee Plume Study of Project STATE. Samples were obtained by employing a triple screen high-volume assembly which contained: (1) a quartz filter for collecting particulate SO/sub 4//sup 2 -/, NO/sub 3//sup -/ and NH/sub 4//sup +/, (2) two NaCl-impregnated cellulose filters for collecting gaseous nitrate, and (3) two K/sub 2/CO/sub 3/-impregnated cellulose filters for collecting SO/sub 2/. Formation rates of sulfate an… more
Date: January 1, 1980
Creator: Forrest, J; Garber, R W & Newman, L
Partner: UNT Libraries Government Documents Department
open access

Summary of HTGR (high-temperature gas-cooled reactor) benchmark data from the high temperature lattice test reactor

Description: The High Temperature Lattice Test Reactor (HTLTR) was a unique critical facility specifically built and operated to measure variations in neutronic characteristics of high temperature gas cooled reactor (HTGR) lattices at temperatures up to 1000{degree}C. The Los Alamos National Laboratory commissioned Pacific Northwest Laboratory (PNL) to prepare this summary reference report on the HTLTR benchmark data and its associated documentation. In the initial stages of the program, the principle of th… more
Date: October 1, 1989
Creator: Newman, D.F.
Partner: UNT Libraries Government Documents Department
open access

Future aircraft and potential effects on stratospheric ozone and climate

Description: The purpose of this study is to extend the recent research examining the global environmental effects from potential fleets of subsonic and supersonic commercial aircraft. Initial studies with LLNL models of global atmospheric chemical, radiative, and transport processes have indicated that substantial decreases in stratospheric ozone concentrations could result from emissions of NO{sub x} from aircraft flying in the stratosphere, depending on fleet size and magnitude of the engine emissions. T… more
Date: October 1, 1991
Creator: Kinnison, D.E. & Wuebbles, D.J.
Partner: UNT Libraries Government Documents Department
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