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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 graphite residue retained > 50% of the long-lived fission products. Three successive leaches of fuel containing uranium and thorium recovered approximates 99% of both elements. Uranium recoveries by combustion in oxygen followed by dissolution of the ash hn nitric acid or fluorlde-catalyzed nitric acid are quantitative only when the fuel is not coated, does not contain Al/sub 2/O/sub 3/-coated fuel particles, and is free from impurities such as iron. During combustion up to 95% of the Ru-106 was volatilized from irradiated specimens. Recoveries, by leaching with 70% HNO/sub 3/, from fuel specimens containing Al/sub 2/O/sub 3/-coated fuel particles were greater than 99% when the specimens were ground finer than 200 mesh to ensure crushing of the fuel particles. (auth)
Date: November 30, 1961
Creator: Ferris, L.M.; Kibbey, A.H. & Bradley, M.J.
Partner: UNT Libraries Government Documents Department
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STUDIES OF THE SCINTILLATION PROCESS IN CsI(Tl)

Description: The scintillation response of CsI(Tl) crystals, having various thallium contents, was measured for excitation of the crystals by monoenergetic gamma rays, protons, and alpha particles. The investi gation was made to provide a test of some of the features of a theoretical model of the scintillation process in thallium-activated alkali iodides proposed by Murray and Meyer. In order to insure that the results obtained in this program would provide a critical test of the scintillation model, special attention was paid to technical effects which could influence the interpretation of the experimental data. For example, the effect of the pulseanalysis time on the relative scintillation response of CsI(Tl) to various charged parti cles was investigated. In addition, the emission spectra of the CsI(Tl) crystals were measured for excitation by x rays, protons, and alpha particles. The results of the investigation showed that the scintillation efficiency of CsI(Tl) is a continuous function of dE/dx, as assumed in the scintillation model, within the accuracy of the experiments when the effect of delta ravs are considered. This led to the conclusion that the light output of CsI(Tl) crystals is, in general, a nonlinear function of the energy of the particle. The shape of the dL/dE versus dE/dx curve for CsI(Tl) crystals is shown to be nearly independent of the thallium content of the crystal. This is in distinct contrast to the predictions of the scinti llation model. An examination of the emission spectra of CsI(Tl) crystals showed that light is emitted in a band, centered at about 3300A, which is characteristic of the emission of the pure crystal, as well as the characteriatic thallium luminescence. The relative intensity of this luminescence with respect to the thallium- activator luminescence increases as the ionization density in the crystal increases and increases as the thallium content decreases. …
Date: November 30, 1962
Creator: Gwin, R. & Murray, R. B.
Partner: UNT Libraries Government Documents Department
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Design of a water jet drill for development of geothermal resources. Progress report, October 1--November 30, 1977

Description: Progress is reported in the evaluation of the performance of a water jet drill in a stressed rock, particularly in drilling at hole diameters in excess of one inch. Drilling tests are being carried out in a barrier pillar in a layer of coarse, lead-bearing sandstone. Problems encountered in the test drilling are discussed. (JGB)
Date: November 30, 1977
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 multiple-gas analyzers. (JRD)
Date: November 30, 1977
Creator: Harrar, J.E. (ed.)
Partner: UNT Libraries Government Documents Department
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Cadmium sulfide/copper sulfide heterojunction cell research. Quarterly technical progress report, June 1-September 30, 1979

Description: Off-stoiciometry CdS coatings with resistivities of about 10..cap omega..-cm have been deposited by a cyclic reactive sputtering process where the H/sub 2/S injection is periodically switched on and off. Cells with CdS layer fabricated in this way have yielded efficiencies of about 0.6% with short circuit currents of about 3.5 mA/cm/sup 2/, open circuit voltages of about 0.43V, and fill factors of about 0.40. CdS resistivity control by In doping has been achieved both by diffusion from a pre-deposited In layer and by using an In-doped Cd sputtering target. Resistivities of about 30..cap omega..-cm are achieved in CdS coatings about 5 um thick deposited at 250/sup 0/C over 50 nm thick In layers. A Cd cathode doped with 1 atomic percent In has yielded CdS coatings with resistivities of about 0.1 ..cap omega..-cm at substrate temperatures in the 100 to 300/sup 0/C range. Cells fabricated from the 0.1 ..cap omega..-cm CdS with a 0.5 um undoped layer adjacent to the junction have yielded encouraging diode characteristics with a strong photovoltaic effect and will be used to an optimization study. Cu/sub x/S coatings deposited onto CdS under various conditions have been found to have the same properties as those deposited onto glass substrates in previous studies. The amount of sputtering that is required in order to deposit the Cu/sub 2/S heterojunction layer is small compared to that requird to achieve steady state conditions in the deposition apparatus. Thus pre-conditioning is required. The results of experiments that examines various conditioning procedures are reported.
Date: November 30, 1979
Creator: Thornton, J.A.
Partner: UNT Libraries Government Documents Department
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Geothermal district-heating potential for casinos/hotels in Reno, Nevada

Description: Results from the pre-feasibility study of a geothermal district heating system for greater Reno and the pre-feasibility study of providing geothermal heat to casinos/hotels located in downtown Reno by connection to the proposed district heating system (DHS) are combined. Geothermal sources were selected from published data. Potential users were selected from aerial and city planning maps, and published building and demographic information. Energy consumption data from the electric and gas utility was matched with consumption information from surveys of representative buildings by category and climatic data. As an example, a written survey was mailed to the casino/hotels and two on-site visits were made. Retrofit methodology and cost were examined for the casino/hotels and representative buildings. Based on the pre-feasibility studies, a geothermal district heating system for Reno appears technically and economically feasible. Furthermore, additional economic savings are achieved when the Reno casinos/hotels are connected to the DHS. Steamboat Hot Springs and a geothermal area east of downtown are the most promising geothermal sources for the DHS. The City of Reno has a large yearly heat load with an average heating degree days per year of 6022/sup 0/F days and a heating season greater than eight months.
Date: November 30, 1981
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 polyenes, and so this approach had its limitations. Direct polymerization of acetylene by Mo(CH-t-Bu)(NAr)(O-t-Bu){sub 2} was more successful, but inherent polyene instability was still a problem. The most important result of the past grant period is the finding that dipropargyl derivatives (HC=CCH{sub 2}XCH{sub 2}C=CH; X = CH{sub 2}, C(CO{sub 2}R){sub 2}, SiR{sub 2}, etc.), which have been reported to be cyclopolymerized by various classical catalysts by as yet unknown mechanisms, are polymerized by Mo(CH-t-Bu)(NAr)(OCMe(CF{sub 3}){sub 2}){sub 2} in dimethoxyethane. We speculate that intramolecular formation of a five-membered ring in the product of {alpha} addition is fast enough to yield another terminal alkylidene on the time scale of the polymerization reaction, while a six-membered ring is formed in a reaction involving a more reaction terminal alkylidene. Either intermediate alkylidene, but most likely the terminal alkylidene, could react with additional monomer to lead to growth of a chain having dangling'' triple bonds that eventually could be employed to form crosslinks.
Date: November 30, 1992
Creator: Schrock, R. R.
Partner: UNT Libraries Government Documents Department
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Transport and thermodynamic properties of solids. Final report

Description: During the last year of operation the principal area of research has been ternary diffusion in solid solution alloys. Specific research projects deal with diffusion in the Cu--Ni--Zn and Fe--Ni--Al systems. Research activities in these areas are summarized.
Date: November 30, 1977
Creator: Grace, R.E. & Dayananda, M.A.
Partner: UNT Libraries Government Documents Department
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Anisotropic yielding of rocks at high temperatures and pressures; Annual Progress Report, 1988-1989

Description: The experimental results we have obtained on Four-Mile gneiss have demonstrated that the yield behavior of quartzo-feldspathic rocks containing only a small percentage (10%) of mica can be markedly anisotropic, provided the mica minerals exhibit a strong crystallographic preferred orientation. Samples of gneiss oriented such that resolved shear stresses on the foliation plane are large are considerably weaker than granites of similar grain size and composition, and this weakness is attributed to enhanced nucleation of microcracks in quartz and feldspar adjacent to mica grains that are suitably oriented for slip. We expect the yield behavior of rocks containing a higher proportion of phyllosilicates to be influenced by the strongly anisotropic nature of these minerals as well, although the strengths, temperature and pressure dependencies, and flow-controlling mechanisms in such rocks may be significantly different.
Date: November 30, 1989
Creator: Kronenberg, A. K.; Russell, J. E. & Carter, N. L.
Partner: UNT Libraries Government Documents Department
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Coal as an option for power generation in US territories of the Pacific

Description: A survey of general considerations relating to the use of coal in US territories and trust territories of the Pacific suggests that coal is a viable option for power generation. Future coal supplies, principally from Australia and the west coast of America, promise to be more than adequate, but large bulk carriers will probably not be able to land coal directly because of inadequate port facilities. Hence, smaller than Panamax-class vessels (60,000 dwt) or some arrangement utilizing self-loading barges or lighters would have to be used. Except for Guam, with peak power requirements on the order of 175 MW/sub e/, most territories have current, albeit inadequate, installations of 1 to 25 MW/sub e/ Turnkey, conventional-coal-fired, electrical-power generating systems are available in that size range. US environmental laws are now applicable to Guam and American Samoa; the trust territories are exempt. However, the small power requirements of many small islands will qualify for exemption from the New Source Performance Standards called for in the Clean Air Act. The principal problems with coal use in the territories, apart from the shallow draft of most harbors, are the limited amount of land available and the high capital costs associated with conversion. Ocean dumping of ash and sludge can be permitted under existing Environmental Protection Agency regulations, and barge-mounted power installations are not out of the question. The feasibility of converting from oil-fired to coal-fired electrical-power generating systems must be determined with site-specific information.
Date: November 30, 1981
Creator: Borg, I. Y.
Partner: UNT Libraries Government Documents Department
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Afghanistan: Politics, Elections, and Government Performance

Description: This report discusses the current political state of Afghanistan, as well as the Afghan government. This report also discusses Afghanistan's relationship with the United States, particularly U.S. efforts to urge President Hamid Karzai to address corruption within the Afghan government.
Date: November 30, 2012
Creator: Katzman, Kenneth
Partner: UNT Libraries Government Documents Department
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Afghanistan: Politics, Elections, and Government Performance

Description: This report discusses the current political state of Afghanistan, as well as the Afghan government. This report also discusses Afghanistan's relationship with the United States, particularly U.S. efforts to urge President Hamid Karzai to address corruption within the Afghan government.
Date: November 30, 2009
Creator: Katzman, Kenneth
Partner: UNT Libraries Government Documents Department
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TMI Unit-2 Technical Information and Examination Program Update

Description: Information is presented concerning a submerged demineralizer system for contaminated water; multilevel sampling; inspection of solar crane; entry on containment building; and shipment of EPICOR 2 resin canister.
Date: November 30, 1981
Partner: UNT Libraries Government Documents Department
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Volume reduction system for solid and liquid TRU waste from the nuclear fuel cycle: April--June 1977

Description: The Cyclone Incinerator development this quarter was concentrated on testing a particular liquid feed and burn system. The liquids tested were limited to tributyl phosphate in kerosene and oil-based vacuum pump oil. The tests established that the system worked as designed and built; that tributyl phosphate (TBP), as much as 30% by weight in kerosene, would burn readily; and that the scrubber system collects and neutralizes phosphoric acid which results from the combustion of TBP. Ash immobilization studies included determinations of leach rates for cemented ash. Plutonium-238 was used as a doping agent for the detection of leaching.
Date: November 30, 1977
Creator: Luthy, D.F. & Bond, W.H.
Partner: UNT Libraries Government Documents Department
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Assessment of proposed federal tax credits for residential wood burning equipment

Description: This report summarizes the results of a study of tax incentives for residential wood burning equipment. It presents an overview of the major issues affecting inclusion or exclusion of this equipment in the NEA tax credit program. The report was prepared as a quick response task within a six week period. Because of these time constraints, many simplifying assumptions had to be made in order to provide information in accordance with the decisionmaking schedule. The report is not meant to be considered as an exhaustive analysis of any particular issue area. (TFD)
Date: November 30, 1979
Partner: UNT Libraries Government Documents Department
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Circulating pump impeller: Presbyterian Intercommunity Hospital, Klamath Falls, Oregon, geothermal heating system. Failure analysis report

Description: The Presbyterian Intercommunity Hospital located in Klamath Falls, Oregon utilizes geothermal fluid pumped from its own well to provide space heat and domestic hot water. During an inspection of the heating system after a chemical cleaning of the heat exchangers, the circulating pump was dismantled to replace its seals which were found to be leaking. At that time, the impeller was found to contain many cracks. The analysis of those cracks and a scale sample removed from the impeller is presented. (MHR)
Date: November 30, 1979
Creator: Mitchell, D.A. & Ellis, P.F.
Partner: UNT Libraries Government Documents Department
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Conceptual design study of the hylife lithium fall laser fusion chamber. FY 1979 annual report

Description: In FY 1979, the basic configuration of FY 1978 was used as a reference point. Many studies were then made to either generate more design information concerning this design or to produce new concepts that would lead to a superior configuration. Among these activities were a detailed weight analysis, an assembly sequence, a chamber vibration analysis, a splash baffle stress study, and an analysis of first wall thermal stresses. Then some new concepts were introduced that pertained to the first wall, the lithium inlet nozzle, the chamber supports, the inlet piping, and pressure vessel.
Date: November 30, 1979
Partner: UNT Libraries Government Documents Department
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Medium-energy nuclear physics research. Final technical progress report, May 1, 1971-November 30, 1981

Description: Final results are summarized for this program with the primary emphasis on measurement of ten independent parameters for proton-proton elastic scattering at 800 MeV and four independent such parameters at 650 MeV. Inelastic proton-proton reactions have also been measured at 800 MeV. Proton-deuteron elastic scattering cross sections and polarization analyzing powers have been obtained at 800 MeV. Proton-nucleus total and total reaction cross sections were measured at 700 MeV for a number of nuclei. Major instrumentation was designed and constructed to carry out this program.
Date: November 30, 1981
Creator: Willard, H.B.
Partner: UNT Libraries Government Documents Department
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Flux of energy and essential elements through the continental shelf ecosystem. Progress report

Description: There are three distinct but not mutually exclusive areas of research in this contract, studies of intrusions of the west wall of the Gulf Stream onto the outer continental shelf, studies of the flux of materials across nearshore density fronts, and advances in understanding of the planktonic food web of the continental shelf. Studies of frontal events on the outer and inner continental shelf involve distinctive physical and chemical regimes and have proven to require distinctive biological approaches. The studies of the food web run through our work on both of the frontal regimes, but certain aspects have become subjects in their own right. We have developed a simulation model of the flux of energy through the continental shelf food web which we believe to be more realistic than previous ones of its type. We have examined several of the many roles of dissolved organic compounds in sea water which originate either from release by phytoplankton, digestive processes or metabolites of zooplankton, or extracellular digestion of microorganisms. Methods have been developed under this contract to measure both the chelating capacity of naturally occurring organic materials and the copper concentration in the water. It has been possible to characterize the effects, both toxic and stimulatory, of copper on photosynthesis of naturally occurring phytoplankton populations. It is possible to characterize in considerable detail the course of biological events associated with meanders of the Gulf Stream. We are now in a position to explain the limits to biological productivity of the outer continental shelf of the southeastern US and the reasons why that biological production moves through the food web in the characteristic way that it does.
Date: November 30, 1981
Creator: Pomeroy, L.R.
Partner: UNT Libraries Government Documents Department
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Asian Carp and the Great Lakes Region

Description: This report discusses four species of non-indigenous Asian carp that are expanding their range in U.S. waterways, resulting in a variety of concerns and problems. Three species--bighead, silver, and black carp--are of particular note, based on the perceived degree of environmental concern. Current controversy relates to what measures might be necessary and sufficient to prevent movement of Asian carp from the Mississippi River drainage into the Great Lakes through the Chicago Area Waterway System. Bills have been introduced in the 111th Congress to direct actions to avoid the possibility of carp becoming established in the Great Lakes.
Date: November 30, 2010
Creator: Buck, Eugene H.; Upton, Harold F.; Stern, Charles V. & Nichols, James E.
Partner: UNT Libraries Government Documents Department
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Sexual Violence in African Conflicts

Description: This report covers the issue of sexual violence in the midst of civil conflict in African nations. Civilians in Africa's conflict zones are often vulnerable to sexual violence, including rape, mutilation, and sexual slavery. This violence is carried out by government security forces and non-state actors, including, rebel groups, militias, and criminal organizations. Some abuses appear to be opportunistic, or the product of a larger breakdown in the rule of law and social order that may occur amid conflict.
Date: November 30, 2010
Creator: Arieff, Alexis
Partner: UNT Libraries Government Documents Department
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Speaking on the House Floor: Gaining Time and Parliamentary Phraseology

Description: This report discusses general clarification guidelines regarding House rules and precedents structure Members' opportunities to speak on the floor about pending legislation.
Date: November 30, 2010
Creator: Rybicki, Elizabeth
Partner: UNT Libraries Government Documents Department
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International Criminal Court Cases in Africa: Status and Policy Issues

Description: This report provides background on current International Criminal Court (ICC) cases and examines issues raised by the ICC's actions in Africa, including the potential deterrence of future abuses and the potential impact on African peace processes.
Date: November 30, 2010
Creator: Arieff, Alexis; Margesson, Rhoda; Browne, Marjorie Ann & Weed, Matthew C.
Partner: UNT Libraries Government Documents Department
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