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Evaluation of extractants and chelating resins in polishing actinide-contaminated waste streams

Description: At the Los Alamos National Laboratory Plutonium Facility, anion exchange is used for recovering plutonium from nitric acid solutions. Although this approach recovers >99%, the trace amounts of plutonium and other actinides remaining in the effluent require additional processing. We are doing research to develop a secondary unit operation that can directly polish the effluent so that actinide levels are reduced to below the maximum allowed for facility discharge. We selected solvent extraction, … more
Date: June 1, 1991
Creator: Schreiber, S. B.; Dunn, S. L. & Yarbro, S. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Synthesis and in-vivo detection of boronated compounds for use in BNCT

Description: The primary objective of the DOE program at The University of Tennessee Graduate School of Medicine is the development of effective molecular medicine for use in neutron-capture therapy (NCT). The research focuses primarily on the preparation of new boron-rich NCT agents and the technology to detect them in-vivo. The detection technology involves the development of effective magnetic resonance imaging (MRI) and spectroscopy (MRS) techniques for verifying and measuring NCT agents in-vivo. The sy… more
Date: January 1, 1992
Creator: Kabalka, G. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dynamic process model of a plutonium oxalate precipitator. Final report

Description: In support of LLL material safeguards program, a dynamic process model was developed which simulates the performance of a plutonium (IV) oxalate precipitator. The plutonium oxalate precipitator is a component in the plutonium oxalate process for making plutonium oxide powder from plutonium nitrate. The model is based on state-of-the-art crystallization descriptive equations, the parameters of which are quantified through the use of batch experimental data. The dynamic model predicts performance… more
Date: November 1, 1977
Creator: Miller, Charles L.; Hammelman, James E. & Borgonovi, Giancarlo M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preparation and properties of Y-124 superconductor made by a chemical precipitation method

Description: We have prepared the thermodynamically stable YBCO-124 high temperature superconductor in powder form by a chemical precipitation method and have characterized the material by a number of chemical and physical methods, including carbon content, x-ray diffraction, thermogravimetry, scanning electron microscopy, surface area, thermally stimulated luminescence, and the superconducting transition and magnetization curves. We have also started to consolidate the powders by hot pressing. 21 refs., 6 … more
Date: January 1, 1990
Creator: Laquer, H. L. (CryoPower Associates, Los Alamos, NM (USA)); Gaines, J. R., Jr.; Brainard, S.; Hutson, S. D.; Pisanelli, J. (Superconductive Components, Inc., Columbus, OH (USA)); Cooke, D. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Enhanced durability of desulfurization sorbents for fluidized-bed applications

Description: To extend the operating temperature range and further improve the durability of fluidizable sorbents, zinc titanate, another leading regenerable sorbent, was selected for development in the later part of this project. A number of zinc titanate formulations were prepared in the 50 to 300 [mu]m range using granulation and spray drying methods. Important sorbent preparation variables investigated included zinc to titanium ratio, binder type, binder amount, and various chemical additives such as co… more
Date: November 1, 1992
Creator: Gupta, R. P. & Gangwal, S. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Steroselective synthesis and application of L-( sup 15 N) amino acids

Description: We have developed two general approaches to the stereoselective synthesis of {sup 15}N- and {sup 13}C-labeled amino acids. First, labeled serine, biosynthesized using the methylotrophic bacterium M. extorquens AM1, serves as a chiral precursor for the synthesis of other amino acids. For example, pyridoxal phosphate enzymes can be used for the conversion of L-({alpha}-{sup 15}N)serine to L-({alpha}-{sup 15}N)tyrosine, L-({alpha}-{sup 15}N)tryptophan, and L-({alpha}-{sup 15}N)cysteine. In the sec… more
Date: January 1, 1991
Creator: Unkefer, C.J. (Los Alamos National Lab., NM (United States)) & Lodwig, S.N. (Centralia Coll., WA (United States). Div. of Science)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thin film cadmium telluride solar cells. Final technical report, July 1, 1979-August 31, 1980

Description: Efforts during this program have been directed to the construction of apparatus for the chemical vapor deposition of cadmium telluride films, the selection and preparation of substrates, the deposition and characterization of cadmium telluride films, and the fabrication and characterization of solar cells. Cadmium telluride films have been deposited on a number of substrates by the direct combination of cadmium and tellurium on the substrate surface at 500/sup 0/C or higher at rates of up to 0.… more
Date: August 1, 1980
Creator: Chu, T. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Synthesis and evaluation of new cathode materials for rechargeable lithium batteries. Annual report, April 26, 1976-September 15, 1977

Description: The objective of the first year of this study was the investigation of two new classes of complex sulfide materials of potential value for ambient and high temperature, high energy rechargeable batteries with lithium anodes. The two new classes were the sulfospinels and simple and mixed layered disulfides of transitional metals of groups IVB and VB. In addition, three simple sulfides, CoS, CoS/sub 2/ and FeS/sub 2/ were also investigated. Studies of the synthesis methods have resulted in the de… more
Date: December 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Selenium and tellurium as carbon substitutes

Description: This review has summarized structure-activity studies with /sup 75/Se- and /sup 123m/Te-labeled radiopharmaceuticals in which the selenium or tellurium heteroatom has been inserted between carbon-carbon bonds. The agents that have been investigated in most detail include steroids for adrenal imaging and long-chain fatty acids, and a variety of other unique agents have also been studied. Because of the great versatility of the organic chemistry of selenium and tellurium, there is continuing inte… more
Date: January 1, 1980
Creator: Knapp, F. F. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reduction of carbon monoxide. Past research summary

Description: Research programs for the year on the preparation, characterization, and reactions of binuclear tantalum complexes are described. All evidence to date suggest the following of these dimeric molecules: (1) the dimer does not break into monomers under mild conditions; (2) intermolecular hydride exchange is not negligible, but it is slow; (3) intermolecular non-ionic halide exchange is fast; (4) the ends of the dimers can rotate partially with respect to one another. The binuclear tantalum hydride… more
Date: October 1, 1981
Creator: Schrock, R.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Efficient microscale preparation of tin-117m-tin tetrachloride-a pivotal intermediate for the synthesis of tin-117m-labeled radiopharmaceuticals

Description: A microscale technique has been developed for the preparation of /sup 117m/SnCl/sub 4/. The radiolabeled tin tetrachloride is an important intermediate for the synthesis of /sup 117m/Sn-labeled organic radiopharmaceuticals. The flow-through system involves high temperature chlorination of metallic /sup 117m/Sn with subsequent cryogenic collection of the /sup 117m/SnCl/sub 4/ in a special reaction vessel. This vessel can then be used for the conversion of the tin tetrachloride to various useful … more
Date: January 1, 1979
Creator: Woo, David V.; Knapp, Furn F., Jr.; Butler, Thomas A. & Callahan, Alvin P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nitration of polynuclear aromatic hydrocarbons in coal combustors and exhaust streams

Description: Our efforts quarter were directed at preparing PAH samples at well-controlled extents of secondary pyrolysis. The same operating conditions used in the past were implemented this quarter to prepare PAH samples at well-controlled extents of secondary pyrolysis from a Pit. [number sign]8 hvA bituminous coal. The new data are in excellent agreement with the old. Both ultimate yield values and soot percentages at particular furnace temperatures from these data sets am within experimental uncertaint… more
Date: February 1, 1993
Creator: Yu, L.; Dadamio, J.; Hildemann, L. & Niska, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Strontium-90 fluoride data sheet

Description: This report is a compilation of available data and appropriate literature references on the properties of strontium-90 fluoride and nonradioactive strontium fluoride. The objective of the document is to compile in a single source pertinent data to assist potential users in the development, licensing, and use of /sup 90/SrF/sub 2/-fueled radioisotope heat sources for terrestrial power conversion and thermal applications. The report is an update of the Strontium-90 Fluoride Data Sheet (BNWL-2284)… more
Date: June 1, 1981
Creator: Fullam, H. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Resin-based preparation of HTGR fuels: operation of an engineering-scale uranium loading system

Description: The fuel particles for recycle of /sup 233/U to High-Temperature Gas-Cooled Reactors are prepared from uranium-loaded carboxylic acid ion exchange resins which are subsequently carbonized, converted, and refabricated. The development and operation of individual items of equipment and of an integrated system are described for the resin-loading part of the process. This engineering-scale system was full scale with respect to a hot demonstration facility, but was operated with natural uranium. The… more
Date: October 1, 1977
Creator: Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Drying of ion-exchange resins for resin-based preparation of nuclear reactor fuels

Description: The reference fuel kernel for recycle of /sup 233/U to HTGRs (High Temperature Gas-Cooled Reactors) is prepared by loading carboxylic acid cation-exchange resins with uranium and carbonizing at controlled conditions. The loaded, dried resin must meet specifications for sphericity, composition, and other properties. Microwave heating is used to give controlled and reproducible drying of 11-liter batches of uranium-loaded (4 kg of uranium) resin in a vessel of safe dimensions for nuclear critical… more
Date: January 1, 1976
Creator: Drago, J. P.; Haas, P. A. & Million, D. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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In-line monitoring of effluents from HTGR fuel particle preparation processes using a time-of-flight mass spectrometer

Description: The carbonization, conversion, and coating processes in the manufacture of HTGR fuel particles have been studied with the use of a time-of-flight mass spectrometer. Non-condensable effluents from these fluidized-bed processes have been monitored continuously from the beginning to the end of the process. The processes which have been monitored are these: uranium-loaded ion exchange resin carbonization, the carbothermic reduction of UO/sub 2/ to UC/sub 2/, buffer and low temperature isotropic pyr… more
Date: August 1, 1976
Creator: Lee, D. A.; Costanzo, D. A.; Stinton, D. P.; Carpenter, J. A.; Rainey, W. T. Jr.; Canada, D. C. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Energy transfer processes in solar energy conversion

Description: During the past year, we have been working in three general areas: electronic excitation transport in clustered chromophore systems and other complex systems, photo-induced electron transfer and back transfer in liquid solutions in which diffusion and charge interactions are important, and the construction of a new two color dye laser system to enhance our experimental capability.
Date: January 1, 1992
Creator: Fayer, M.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High octane ethers from synthesis gas-derived alcohols. [Methyl isobutyl ether(MIBE) and methyl tertiary butyl ether(MTBE)]

Description: The testing of strongly acidic catalysts for the conversion of a mixture of methanol and isobutanol to ethers and hydrocarbons was continued. Under standardized test conditions the catalysts tested this quarter were: phosphotungstic acid supported on zirconia (PW[sub 12]/ZrO[sub 2]), niobic acid'' (Nb[sub 2]O[sub 5]xH[sub 2]0), and an iron and manganese doped sulfate-modified zirconia (Fe/Mn/ZrO[sub 2]/SO[sub 4][sup [minus]2]). The overall activity of these catalysts followed the order of Fe/Mn… more
Date: February 1, 1993
Creator: Klier, Kamil; Herman, Richard G.; Johansson, Marie A. & Feeley, Oowen C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear Medicine Program progress report, quarter ending March 31, 1992

Description: We describe the design synthesis and initial animal testing of a new iodine-131-labeled triglyceride analogue for the potential evaluation of clinical pancreatic insufficiency. The new agent is 1,2-dipalmitoyl-3-((15-p-iodophenyl)pentadecanoyl) rac-glycerol(1,2-Pal-3-IPPA). Following oral administration of the iodine-125-labeled agent to rats, 34.5+8.8% of the administered activity was excreted in the urine within one day, demonstrating that radioiodinated IPPA is absorbed in the intestine afte… more
Date: July 1, 1992
Creator: Knapp, F. F. Jr.; Ambrose, K. R.; Callahan, A. P.; McPherson, D. W.; Mirzadeh, S.; Hasan, A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gas Hydrates: Technology Status Report January 1987

Description: In 1983, the US Department of Energy (DOE) assumed the responsibility for expanding the knowledge base and for developing methods to recover gas from hydrates. These are ice-like mixtures of gas and water where gas molecules are trapped within a framework of water molecules. This research is part of the Unconventional Gas Recovery (UGR) program, a multidisciplinary effort that focuses on developing the technology to produce natural gas from resources that have been classified as unconventional … more
Date: January 1, 1987
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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''Small'' accelerator, radionuclide and radiopharmaceutical production

Description: The scope of this discussion is limited to the proton/deuteron accelerators capable of producing the positron emitting isotopes carbon-11, nitrogen-13, oxygen-15, and fluorine-18. Attention is focussed on the production process from the selection of the target gas to the synthesis of the desired radiopharamaceutical. (GHT)
Date: January 1, 1978
Creator: Ruth, T. J. & Wolf, A. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synthesis of cresols and xylenols from benzene and methanol

Description: The objective of the work is to compare two processes for manufacturing cresols and xylenols: (1) a conventional catalytic process, and (2) a photo-thermal catalytic process, in order to determine the relative process economics. The products are used primarily as chemical intermediates for manufacture of antioxidants, pesticides, polymerization inhibitors, resins, and other products. The market is approximately 500 million pounds per year. This report is the second of two reports, presenting re… more
Date: April 1, 1992
Creator: Prengle, H. W., Jr.; Bricout, F. A. & Alam, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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