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Mass Transfer Coefficients and Interfacial Area in a One Stage Pulse Column

Description: Over-all mass transfer coefficients were determined independently of the interfacial area by considering the operation of the pulse column to be a stage- wise process. The calculated coefficients describe only the operation of the pulse column for the free rise of organic droplets through a stage, since in the downstroke the aqueous phase passes through the organic phase in the form of rivulets preferentially wetting the plates. The driving force for transfer was based on the aqueous phase conc… more
Date: November 1, 1960
Creator: Konopik, A. E. & Burkhart, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radio chemistry as a diagnostic in laser fusion experiments

Description: Nuclear chemistry techniques have been employed in an attempt to measure the density of high compression laser fusion targets. Radioactive /sup 28/Al atoms formed in the /sup 28/Si(n,p)/sup 28/Al reaction arising from the interaction of the 14 MeV neutrons with the silicon atoms in the glass microsphere have been counted at Lawrence Livermore Laboratory using a ..beta..-..gamma.. coincidence method. The detection system that is employed allows activities corresponding to 100 aluminum atoms to b… more
Date: November 1, 1977
Creator: Campbell, E.M.; Hicks, H.G.; Mead, W.C.; Glaros, S.S.; Coleman, L.W. & Laird, W.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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PROCESSES FOR RECOVERY OF URANIUM AND THORIUM FROM GRAPHITE-BASE FUEL ELEMENTS. PART II

Description: Laboratory-scale tests on methods for recovering uranium and thorium from graphite-base reactor fuel elements are reported. The 90% HNO/sub 3/ process, which involves simultaneous disintegration and leaching in 21 M HNO/sub 3/, is applicable to all fuel elenments which do not contain coated fuel particles. Leaching of irradiated (0.001% burnup) fuels containing 3 and 12% uranlum recovered approximates 99.3 and 99.9%, respectively, of the uranium in two 4-hr leaches with boiling acid. The graphi… more
Date: November 30, 1961
Creator: Ferris, L.M.; Kibbey, A.H. & Bradley, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies on transition metals and alloy Fischer-Tropsch catalysts, their electronic and bulk properties. (I: Fe/MnO; II: Fe/TiO/sub 2/; III: Fe/Mord. ). Final report, July 1, 1982-September 30, 1983

Description: The objectives were: (1) to characterize samples D1, 10% FeO/90% MnO, and D2, 48% FeO/52% MnO, under varying conditions of reduction (at 250/sup 0/C or 350/sup 0/C in H/sub 2/) and of syngas reaction 1:1 of CO:H/sub 2/ at 290/sup 0/C) and in some cases use CO only for reduction and to identify species by Moessbauer Spectroscopy and Magnetization (sigma/sub s) measurement; (2) similarly, to see if there is any metal (oxide)/support (Mordenite) interaction by the same techniques. The characteriza… more
Date: November 1, 1983
Creator: Mulay, L.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of Hydrocarbon Diluents for the Purex Process

Description: Forty-nine hydrocarbon products were evaluated in the laboratory in a search for a highly stable diluent for the organic extractant used in a radiochemical separations plant. The formation of zirconium ligands during chemical and radiolytic degradation increased with boiling point for isoparaffinic producte but was approximately constant for n-parafiins. Of those materials that met the local flash point specification, the n-parafiins were superior. (auth)
Date: November 1, 1961
Creator: Dennis, B. P. & West, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Arsenic Removal From Gaseous Streams

Description: Uranium feed materials, depending on the production process, have been found to contain arsenic (As) as a contaminant. Analyses show the As to be present as As pentafluoride (AsF{sub 5}) and/or hexafluoroarsenic acid (HAsF{sub 6}) and enter the enrichment cycle through contaminated hydrogen fluoride (HF). Problems related to corrosion of cylinder valves and plugging of feed lines and valves have been attributed to the As. Techniques to separate AsF{sub 5} from uranium hexafluoride (UF{sub 6}) u… more
Date: November 22, 1989
Creator: Russell, R. G. & Otey, M. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Equilibrium of the System Lanthanum Nitrate-Praseodymium Nitrate-Nitric Acid-Water-Tributyl Phosphate

Description: A study of the extraction characteristics of the three systems lanthanum nitrate--nitric acid--water--tributyl phosphate, praseodymium nitrate--nitric acid--water--tributyl phosphate, and lanthanum nitrate--praseodymium nitrate nitric acid -water--tributyl phosphate was conducted. The separation factors between praseodymium and lanthanum for the system lanthanum nitrate--praseodymium nitrate-nitric acid--water--tributyl phosphate were shown to be a function of the total nitrate concentration of… more
Date: November 1, 1960
Creator: Sharp, B. M. & Smutz, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Process for the Recovery of Uranium From Nuclear Fuel Elements Using Fluid-Bed Drying and Volatility Techniques

Description: A process scheme for the recovery of uranium from fuel elements has been developed. The scheme combines continuous fluid-bed drying and fluoride volatility techniques after initial dissolution of the fuel element in the appropriate aqueous system, hence the designation ADF, Aqueous Dry Fluorination Process. The application of this process to the recovery of uranium from highly enriched, low uranium-zirconium alloy plate-type fuels is described. ln the process, the feed solution is sprayed horiz… more
Date: November 1, 1961
Creator: Levitz, N.; Barghusen, J.; Carls, E. & Jonke, A. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Salinity variations and chemical compositions of waters in the Frio Formation, Texas Gulf Coast. Annual report

Description: Waters produced from sandstone reservoirs of the deep Frio Formation exhibit spatial variations in chemical composition that roughly coincide with the major tectonic elements (Houston and Rio Grande Embayments, San Marcos Arch) and corresponding depositional systems (Houston and Norias deltas, Greta-Carancahua barrier/strandplain system) that were respectively active along the upper, lower, and middle Texas Coast during Frio deposition. Within an area, salinities are usually depth dependent, an… more
Date: November 1, 1981
Creator: Morton, R. A.; Garrett Jr., C. M.; Posey, J. S.; Han, J. H. & Jirik, L. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Energy-related doctoral scientists and engineers in the United States, 1975

Description: The pursuit of a vigorous research and development program to provide renewable and other resources to meet U. S. energy needs in the next century is an important objective of President Carter's National Energy Plan. A highly educated and motivated pool of engineers and scientists must be available for energy research and development if this objective is to be achieved. This report provides, for the first time, information about the number and characteristics of doctoral-level engineers an… more
Date: November 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Relationship of regional water quality to aquifer thermal energy storage

Description: Ground-water quality and associated geologic characteristics may affect the feasibility of aquifer thermal energy storage (ATES) system development in any hydrologic region. This study sought to determine the relationship between ground-water quality parameters and the regional potential for ATES system development. Information was collected from available literature to identify chemical and physical mechanisms that could adversely affect an ATES system. Appropriate beneficiation techniques to … more
Date: November 1, 1983
Creator: Allen, R.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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General Chemistry Division quarterly report, July--September 1977

Description: Analytical research and development work is reported on multielement analysis, time-resolved spectroscopy, fluorescence analysis, ionization potential of NP, excited state chemistry, polarized x ray sources, potentiometric titration of Na, determination of TATB in DMSO, determination of nitrobenzene in TATB, analysis of explosive composites, mass spectrometer automation, mass spectra calculation, solids formation in geothermal brine, water quality laboratory automation, aerosol coagulation, and… more
Date: November 30, 1977
Creator: Harrar, J.E. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalysis studies

Description: The New Research Initiatives Program (NRIP) project on catalysis in Los Alamos Scientific Laboratory (LASL) Group CMB-8 has made significant progress towards performing the first basic in situ experimental studies of heterogeneous catalysis on solid compound surfaces in a LEED-Auger system. To further understand the surface crystallography of a possible catalyst compound, LEED-Auger measurements were made on UO/sub 2/(approximately 100) vicinal surfaces. These (approximately 100) vicinal surfac… more
Date: November 1, 1977
Creator: Taylor, T. N. & Ellis, W. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some nitrogen-14 NMR studies in solids

Description: The first order quadrupolar perturbation of the /sup 14/N NMR spectrum yields information regarding the static and dynamic properties of the surrounding electronic environment. Signal to noise problems caused by long /sup 14/N longitudinal relaxation times (T/sub 1/) and small equilibrium polarizations are reduced by rotating frame cross polarization (CP) experiments between /sup 14/N and /sup 1/H. Using quadrupolar echo and CP techniques, the /sup 14/N quadrupolar coupling constants (e/sup 2/q… more
Date: November 1, 1983
Creator: Pratum, T. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron microscopy of hydrocarbon production in parthenium argentatum (guayule)

Description: The electron microscope was used to study the biological processes involved in hydrocarbon production. The little desert shrub Guayule (Parthenium argentatum) was selected for study. This shrub can produce hydrocarbons (rubber) in concentrations up to 1/4 of its dry weight. It grows on semi-arid land and has been extensively studied. The potential of Guayule is described in detail. Results of an investigation into the morphology of Guayule at the electron microscope level are given. Experiments… more
Date: November 1, 1977
Creator: Bauer, T.E.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Systems studies on the extraction of uranium from seawater

Description: This report summarizes the work done at MIT during FY 1981 on the overall system design of a uranium-from-seawater facility. It consists of a sequence of seven major chapters, each of which was originally prepared as a stand-alone internal progress report. These chapters trace the historical progression of the MIT effort, from an early concern with scoping calculations to define the practical boundaries of a design envelope, as constrained by elementary economic and energy balance consideration… more
Date: November 1, 1981
Creator: Driscoll, M.J. & Best, F.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of Vanadium in Milk Powder by Neutron Activation Analysis Using a Rapid Radiochemical Separation of 3.77-Minute Vanadium-52

Description: A procedure is described for the activation determination of V in powdered milk using 3.77-min V/sup 52/. The quantity of V in the sample is obtained by comparing the V/sup 52/ radioactivity found in the test sample with the V/sup 52/ radioactivity in a V comparator sample that is treated in the same manner as the test sample. The procedure can also be used for the determination of V in a variety of materials. (P.C.H.)
Date: November 15, 1963
Creator: Molinski, V. J.; Wahl, W. H. & Strain, W. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Numerical simulations of heterogeneous chemical reactions coupled to fluid flow in varying thermal fields

Description: A numerical simulator of reactive chemical transport with coupling from precipitation-dissolution reactions to fluid flow, via changes of porosity and permeability, is applied to precipitation-dissolution of quartz and calcite in spatially and temporally variable fields of temperature. Significant effects on fluid flow are found in the quartz-silicic acid system in the presence of persistent, strong gradient of temperature. Transient heat flow in the quartz-silicic acid system and in a calcite-… more
Date: November 1, 1991
Creator: Carnahan, C.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laboratory Investigation of Decontaminating Solutions for Primary Loop Decontamination in the New Production Reactor

Description: An investigation was made of methods for decontaminating the primary loop of the New Production Reactor (NPR). Decontamination factors ranging from fifty to several thousand were obtained with several different combinations of cleaning solutions. In general, fission product activity was removed to a lower residual level than was activated corrosion product activity, and carbon steel was easier to decontaminate than was stainless steel. It was necessary to completely remove the oxide film from t… more
Date: November 1, 1960
Creator: Mendel, J. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Controlled Synthesis of Polyenes by Catalytic Methods. Progress Report for the period December 1, 1989 - November 30, 1992

Description: A more direct approach to polyenes by the direct polymerization of acetylenes has been achieved. We were able to show that polymerization of acetylene itself can be controlled with a well- characterized alkylidene catalyst, but only if a base such as quinuclidine is present in order to slow down the rate of propagation relative to initiation. (Quinuclidine may also stabilize vinylalkylidene intermediates formed in the reaction). Unfortunately, living polyenes'' were no more stable than isolated… more
Date: November 30, 1992
Creator: Schrock, R. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electroformation of uranium hemispherical shells

Description: This effort was directed at developing an electrochemical process for forming uniform and dendrite-free deposits of uranium from molten salts. This process is to be used for the electroformation of free-standing hemispherical shells of uranium for nuclear applications. Electrodeposition of uranium onto a substrate was accomplished with a fused chloride mixture containing 42 wt% UCl{sub 3} and a fused chloride-fluoride mixture containing 4 wt % UF{sub 4}. Under pulsed potential control at 504{de… more
Date: November 1, 1989
Creator: Marshall, S.L.; Redey, L.; Vandegrift, G.F. & Vissers, D.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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