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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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Introduction to the Legislative Process in the U.S. Congress

Description: Report that introduces the main steps through which a bill (or other item of business) may travel in the legislative process, from introduction to committee and floor consideration to possible presidential consideration.
Date: November 30, 2012
Creator: Heitshusen, Valerie
Partner: UNT Libraries Government Documents Department
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Federal Emergency Management: A Brief Introduction

Description: Report that is designed to provide Members of Congress and congressional staff with a general overview of principles and foundations of federal emergency management in the United States as well as the types of activities provided by various federal agencies.
Date: November 30, 2012
Creator: Lindsay, Bruce R.
Partner: UNT Libraries Government Documents Department
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The New START Treaty: Central Limits and Key Provisions

Description: Report providing an overview of the New Strategic Arms Reductions Treaty (START), including a comparison to the original START Treaty, the belief of the Obama Administration and outside analysts that New START will enhance U.S. national security, and the criticisms of those who say that New START is a distraction from more important items on the nonproliferation agenda.
Date: November 30, 2012
Creator: Woolf, Amy F.
Partner: UNT Libraries Government Documents Department
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Addressing the Long-Run Budget Deficit: A Comparison of Approaches

Description: Report that examines alternative approaches to reducing the deficit, relating to the immediate issues arising from the Budget Control Act and the expiring tax cuts as well as to ongoing longer term decisions about how to bring the debt under control.
Date: November 30, 2012
Creator: Gravelle, Jane G.
Partner: UNT Libraries Government Documents Department
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Afghanistan: Politics, Elections, and Government Performance

Description: Report that 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. Election fraud and corruption in Afghanistan are also discussed.
Date: November 30, 2012
Creator: Katzman, Kenneth
Partner: UNT Libraries Government Documents Department
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Health Benefits for Members of Congress

Description: Report that covers health benefits made available to Members of Congress through federal government employment, including Federal Employees Health Benefits Program (FEHBP), dental and vision insurance, flexible spending accounts, long-term care insurance, services at the Office of the Attending Physician and military hospitals, and Medicare. It also offers a comparison of FEHBP to health benefits offered by the private sector and state and local governments and a discussion of the effect of the Affordable Care Act (ACA) on Members' health benefits.
Date: November 30, 2012
Creator: Cornell, Ada S.
Partner: UNT Libraries Government Documents Department
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Mental Health and Substance Use: Employers' Insurance Coverage Maintained or Enhanced Since Parity Act, but Effect of Coverage on Enrollees Varied

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The Paul Wellstone and Pete Domenici Mental Health Parity and Addiction Equity Act of 2008 (MHPAEA) requires that employers who offer health insurance coverage for mental health conditions and substance use disorders (MH/SU) provide coverage that is no more restrictive than that offered for medical and surgical conditions. Employers were required to comply with the law for coverage that began on or after October 3, 2009. The Department of Labor (DOL), the Department of Health and Human Services (HHS), and the Department of the Treasury share oversight for MHPAEA. MHPAEA also requires GAO to examine trends in health insurance coverage of MH/SU. This report describes (1) the extent to which employers cover MH/SU through private health insurance plans, and how this coverage has changed since 2008; and (2) what is known about the effect of health insurance coverage for MH/SU on enrollees' health care expenditures; access to, or use of, MH/SU services; and health status. GAO surveyed a random sample of employers about their MH/SU coverage for the most current plan year and for 2008. GAO received usable responses from 168 employers--a 24 percent response rate. The survey results are not generalizable; rather, they provide information limited to responding employers' MH/SU coverage. GAO reviewed published national employer surveys on health insurance coverage and interviewed officials from DOL, HHS, and other experts. GAO also reviewed studies that evaluated the effect of MH/SU coverage on enrollees' expenditures, access to, or use of, MH/SU services, and health status."
Date: November 30, 2011
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department
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Defense Acquisitions: Challenges Remain in Developing Capabilities for Naval Surface Fire Support

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Since the mid-1990s, the Navy and Marine Corps have studied ways to better protect landing forces. As new operational concepts evolved, the Marine Corps identified requirements for naval surface fire support and the Navy began developing two systems to meet these needs--the Extended Range Munition for existing classes of ships and the future Zumwalt class destroyer. GAO was asked to address (1) whether requirements for fire support have been established and (2) the Navy's progress on the Extended Range Munition, Zumwalt class destroyer, and follow-on systems. GAO also analyzed whether these Navy systems fulfill the requirements and whether gaps remain. To address these objectives GAO analyzed key documents on requirements and programs and held discussions with officials from the Navy and Marine Corps as well as other interested organizations."
Date: November 30, 2006
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department
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U.S. Labor Force Statistics: Illustrative Simulations of the Likely Effects of Underrepresenting Unauthorized Residents

Description: A letter report issued by the Government Accountability Office with an abstract that begins "In times of economic uncertainty as well as in times of stability, policymakers and the public rely on labor force statistics, such as the unemployment rate, to provide important information on the current state of the economy. These statistics, published by the Department of Labor's Bureau of Labor Statistics (BLS), include key figures that are based on data obtained from the Current Population Survey (CPS). The CPS, a household interview survey administered by the Department of Commerce's U.S. Census Bureau, is designed to represent the entire United States civilian noninstitutional population. However, certain U.S. residents--specifically, foreign-born persons who are not authorized to live here, to whom the Government Accountability Office (GAO) refers as unauthorized residents in this report--may not be represented in CPS data to the same extent as the general population. Little research has been done on whether potential underrepresentation of the unauthorized population might noticeably affect labor statistics, but policy efforts that depend on valid and reliable labor force statistics would benefit from such information. GAO agreed with the Bureau of Labor Statistics to examine issues concerning unauthorized residents' impact on labor force statistics. GAO addressed the following key questions: (1) Extent of underrepresentation: What is known about the extent of any underrepresentation of unauthorized residents in CPS data used to compile labor force statistics?; (2) Labor force status: What is known about the likely labor force status of unauthorized residents?; (3) Possible effects: How might CPS underrepresentation of unauthorized residents affect key labor force statistics?"
Date: November 30, 2009
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department
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Medicare: Payment for Ambulatory Surgical Centers Should Be Based on the Hospital Outpatient Payment System

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Medicare pays for surgical procedures performed at ambulatory surgical centers (ASC) and hospital outpatient departments through different payment systems. Although they perform a similar set of procedures, no comparison of ASC and hospital outpatient per-procedure costs has been conducted. The Medicare Prescription Drug, Improvement, and Modernization Act of 2003 directed GAO to compare the relative costs of procedures furnished in ASCs to the relative costs of those procedures furnished in hospital outpatient departments, in particular, how accurately the payment groups used in the hospital outpatient prospective payment system (OPPS) reflect the relative costs of procedures performed in ASCs. To do this, GAO collected data from ASCs through a survey. GAO also obtained hospital outpatient data from the Centers for Medicare & Medicaid Services (CMS)."
Date: November 30, 2006
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department
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Nonproliferation and Disarmament Fund: State Should Better Assure the Effective Use of Program Authorities

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The Department of State's (State) Nonproliferation and Disarmament Fund (NDF) has several key authorities that provide it significant operational flexibility; however, it has not determined its needed carryover balances and it has taken years to close out many of its projects in the absence of guidance for closing them. Annual appropriations bills have consistently provided NDF with three key authorities that it has used to carry out its activities. First, NDF has the authority to undertake projects notwithstanding any other provision of law. NDF has used this authority to fund projects in countries, such as North Korea, where U.S. assistance is prohibited by U.S. sanctions and other legal restrictions. Second, NDF has the authority to undertake projects globally. NDF has used this authority to fund projects in numerous regions around the world, in contrast with other U.S. nonproliferation programs, which have historically focused on countries in the former Soviet Union. Third, NDF's appropriations do not expire within a particular time period, enabling NDF to carry over balances from year to year not designated for specific projects. However, NDF has not determined appropriate levels for these balances, which increased significantly in the past few years. Additionally, NDF has sometimes taken many years to close projects, including those where work was never started or was suspended, and has not established criteria to determine when inactive projects should be closed and unexpended resources made available for other projects. As a result, NDF funds may be tied up for years in inactive projects, precluding the funds' use for other projects."
Date: November 30, 2012
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department
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