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Aerodynamic Re-Entry Analysis. Task 2. Thermoelectric Generator Summary Report

Description: An analytical trajectory and aerothermodynamic analysis of a satellite containing a Task 2 thermoelectric generator was completed. A 300-statute mile circular polar orbit was used for this analysis and the launch was assumed to be from Vandenberg Air Force Base. Results of this study show that upon natural decay from a successful mission, the radio-cerium fuel will burn up in space at high altitude, thus only a very minor amount of radio cerium will be released to the stratosphere. A complete analyses of the fate of the radio-cerium fuel following various aborted launching attempts also was carried out. Charts summarizing the various assumed failures and locations of the fuel following failure are shown. A technical discussion of the methods used in performing the analysis is included in the report. (auth)
Date: December 27, 1960
Creator: Oehrli, R.
Partner: UNT Libraries Government Documents Department
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Mechanism of current modulation by optic phonon emission in heterojunction tunneling experiments

Description: We explain recent observations by Hickmott et al. of sequential longitudinal optic phonon emission in tunneling currents of GaAs-Al/sub x/Ga/sub 1-x/As heterojunctions in terms of inhomogeneous tunneling and a magnetopolaronic mass correction. 16 refs., 13 figs.
Date: August 27, 1985
Creator: Hanna, C.B.; Hellman, E.S. & Laughlin, R.B.
Partner: UNT Libraries Government Documents Department
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Development of ultrafiltration and inorganic adsorbents for reducing volumes of low-level and intermediate-level liquid waste: January--March 1978

Description: The exposure of noncellulosic ultrafiltration membranes to a radioactive environment simulating up to 24 months of exposure to a beta dose of 10 ..mu..Ci/cm/sup 3/ and a gamma dose of 10/sup -5/ ..mu..Ci/cm/sup 3/ did not show any conclusive evidence of membrane degradation. Viscosity measurements for control membranes and irradiated membranes indicate no changes in polymer molecular weight were caused by the radiation exposure. This, in turn, suggests no physical or mechanical degradation took place. A continuous run on the ultrafiltration pilot plant was completed. The run lasted 33.5 hr; during this period, the flux declined from 4 gal/min to 0.8 gal/min while rejection of alpha activity increased slightly. A total of 20,000 gal were processed through the ultrafiltration system. The small laboratory column tests were continued with uranium-233 and americium-241. Several new resins were being evaluated along with the same type of resin as used before with uranium-233 and plutonium-238. Tests were continued with the 2-in. Engineering Columns using ultrafiltration product spiked with uranium-233.
Date: April 27, 1978
Creator: Koenst, J. W.; Herald, W. R. & Roberts, R. C.
Partner: UNT Libraries Government Documents Department
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The Seniority System: Pros, Cons, and Suggested Reforms

Description: This report discusses the seniority system in Congress used to select committee chairman and efforts to reform the system.
Date: May 27, 1970
Creator: Oleszek, Walter J.
Partner: UNT Libraries Government Documents Department
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Nepal, Sikkim and Bhutan: A Bibliography

Description: This report is a bibliography that cites information of Nepal, Bhutan, and Sikkim, and includes three major contents related to them: General Works; Government, Politics, Economy; and Foreign relations.
Date: January 27, 1970
Creator: Niksch, Larry A.
Partner: UNT Libraries Government Documents Department
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A Proposed Congressional General Counsel

Description: This report is a proposal for a Congressional general counsel in the 89th Congress.
Date: August 27, 1971
Creator: Sharp, Freeman W.
Partner: UNT Libraries Government Documents Department
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Mexican-United States Relations Since the Beginning of the Good Neighbor Policy

Description: This report discusses The Good Neighbor policy instituted by President Franklin D. Roosevelt and its effects on U.S. relations with Mexico as well as contemporary issues in Mexican-American relations such as immigration, drug smuggling, and trade regulations.
Date: January 27, 1970
Creator: Hannifin, Rieck B.
Partner: UNT Libraries Government Documents Department
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Fundamental Studies of Erosion for Coal Gasification Systems. Annual Progress Report, 1 November 1979-30 June 1980

Description: The effort in this program is divided between modelling the particle impact event using numerical methods and computer calculations and actual measurement of erosion rates. While the results obtained from each of these activities must be combined to provide an improved understanding of particulate erosion of ductile materials, it is convenient to describe separately the progress in each activity area. The first step in the application of the finite element method to any problem is the dissolution of the continuum into small elements. The intent of this procedure is to use as few total elements as possible and to make the elements small where gradients are large and vice versa. The exact solution for the contact of a rigid cylinder with an elastic surface is available from Hertz. This solution has been compared with the computer results obtained from finite element maps containing 148, 273, and 474 elements. The correlation between the computer results and elastic solution is not good for the map with the fewest elements, but improves as the number of elements increases. Convergence to this exact solution has been examined as a function of the number of map elements as a means of improving the efficiency of the design process used to obtain the maps. Having done this, the next step was to include the effects of plasticity. In order to validate the model, the measurement of erosion rates and observation of damage on eroded samples is necessary. Since it takes billions of impacts to lead to measurable weight loss, the experiment must be carefully designed to assure meaningful results. Three facets of the experimental portion of this study are described: the construction of the erosion apparatus, the characterization of the erosion environment and the preliminary erosion results.
Date: July 27, 1980
Creator: Follansbee, P. S.; Sinclair, G. B. & Williams, J. C.
Partner: UNT Libraries Government Documents Department
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EGCR EXPERIMENTAL LOOPS, PRELIMINARY DESIGN REPORT

Description: The EGCR was designed to accommodate up to four gascooled experimental loops plus several experimental fuel elements in the open core. Two of the loops will utilize 51/2-in.-O.D. stainless steel tubes passing through the core along an axis which is about 17 in. from the central axis of the core. The other two loops will utilize 91/2-in.-o.d. tubes about 68 in. from the central axis. Inherent safety in the design, facility design, primary loop design, auxiliary systems and equipment design, primary and secondary containment design, instrumentation and controls, and special operations are discussed. (M.C.G.)
Date: March 27, 1962
Creator: Neill, F.H. & Michelson, C.
Partner: UNT Libraries Government Documents Department
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Two dimensional NMR and NMR relaxation studies of coal structure

Description: This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inversion methods utilizing the difference in heat capacities of small groups of spins are particularly promising. Methods combining proton-proton spin diffusion with {sup 13}C CPMAS readout are being developed to determine the connectivity of functional groups in coals in a high sensitivity relay type of experiment. Additional work is aimed a delineating the role of methyl group rotation in the proton NMR relaxation behavior of coals.
Date: May 27, 1992
Creator: Zilm, K.W.
Partner: UNT Libraries Government Documents Department
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SURFACE PREPARATION OF METALLOGRAPHIC SPECIMENS OF ZIRCONIUM-BASE ALLOYS CONTAINING COPPER

Description: A combination of chemical and electrolytic polishing was successful in the metallographic preparation of Zr--1% Cu and Zr--1.6% Cu alloys. Chemical polishing produced flat surfaces that were suitable for examination with polarized light but were not suitable for examination with bright-field illumination. Electrolytic polishing applied to ground or mechanically polished specimens produced surfaces that were well etched but often were pitted heavily. A chemical polish followed by a short electrolytic polish produced microstructures suitable for examination with both bright-field and polarized light at high or low magnifications. (auth)
Date: October 27, 1961
Creator: Spruiell, J.E. & Hewette, D.M. II
Partner: UNT Libraries Government Documents Department
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Theoretical and experimental studies of churn flow in vertical tubes. Final technical report

Description: The pattern known as churn flow is a highly unsteady pattern with stochastic features and is extremely complex. However, calculations show that for many geothermal wells the condition of churn flow consists over much of the length of the two phase zone. Furthermore, it frequently exists at the surface so that design of separation equipment and surface piping depends on the accurate modelling of this type of flow. It has been the long term purpose of this project to develop physically based models for churn flow which can be used as a basis for predicting holdup, frictional loss and heat transfer rates for this flow pattern in geothermal systems. To achieve this end, it was necessary to develop new methods for measuring the time dependent characteristics of the flow and thus be able to uncover the basic physics of the flow. Models can then be developed based on this understanding which characterizes the flow and equations for holdup, friction and heat transfer evolved.
Date: January 27, 1986
Partner: UNT Libraries Government Documents Department
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Fundamental characterization of alternate fuel effects in continuous combustion systems. Summary technical progress report, August 15, 1978-January 31, 1980

Description: The overall objective of this contract is to assist in the development of fuel-flexible combustion systems for gas turbines as well as Rankine and Stirling cycle engines. The primary emphasis of the program is on liquid hydrocarbons produced from non-petroleum resources. Fuel-flexible combustion systems will provide for more rapid transition of these alternative fuels into important future energy utilization centers (especially utility power generation with the combined cycle gas turbine). The specific technical objectives of the program are: (a) develop an improved understanding of relationships between alternative fuel properties and continuous combustion system effects, and (b) provide analytical modeling/correlation capabilities to be used as design aids for development of fuel-tolerant combustion systems. This is the second major report of the program. Key experimental findings during this reporting period concern stirred combustor soot production during operation at controlled temperature conditions, soot production as a function of combustor residence time, an improved measurement technique for total hydrocarbons and initial stirred combustor results of fuel nitrogen conversion. While the results to be presented concern a stirred combustor which utilizes premixed fuel vapor/oxidant mixtures, a new combustor which combusts liquid fuel injected into the reactor as a spray has been developed and will be described. Analytical program progress includes the development of new quasiglobal models of soot formation and assessment of needs for other submodel development.
Date: February 27, 1980
Creator: Blazowski, W.S.; Edelman, R.B. & Wong, E.
Partner: UNT Libraries Government Documents Department
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Single Element Flow Tests for Type 3 (SM-2) Fuel Elements in SM-1, SM-1A, and PM-2A Cores

Description: Channel-to-channel flow distribution within Type 3 (SM-2, stationary and control rod fuel elements modified for use in the SM-1, SM1-1A, and PM-2A core support structures and control rod tubes was measured in single element flow testing. Plots of channel-to-channel flow distribution and element pressure drop at various element flow rates are given. Flow distribution for the top-orificed SM-1A and PM-2A stationary elements was within the plus or minus 12% deviation from element average utilized in previous thermal analyses of these cores. Testing of the bottom-orificed SM-1 stationary element and the SM-1, SM-1A, and PM-2A control rod assemblies showed flow distribution exceeded plus or minus 12% devation from average. Simple modifications to the SM-1 stationary element indicated the possibility of improvng fiow distribution in that element. (auth)
Date: November 27, 1961
Creator: Krause, P. S.
Partner: UNT Libraries Government Documents Department
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Model for H/sup -/ and D/sup -/ production by hydrogen backscattering

Description: The Marlowe Monte-Carlo backscattering code has been used to calculate particle reflection coefficients and energy distributions for H, D incident upon Li, K, Ni, Cu, Mo, Ag, Cs, Hf, W, Pt, and U surfaces. The backscattered energy and angular distributions are combined with a model for formation and survival probabilities for H/sup -/, D/sup -/ leaving the surface. A least-squares fit of experimental measurements of H/sup -/ yields from the composite surface, Cs/Cu, has been used to obtain two semi-empirical constants, ..cap alpha.., ..beta.. which enter into the formation and survival probabilities. These probabilities are used to calculate the production probability which in turn provides an upper limit to the negative ion yield. The choice of electrode material is discussed as a function of atomic number.
Date: May 27, 1980
Creator: Hiskes, J.R. & Schneider, P.J.
Partner: UNT Libraries Government Documents Department
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Thermal Stress Testing of Type 1 Fuel Plates

Description: Thermal stress tests on Type 1, SM-1A Core II fuel ele-ment sections were performed to study plate distortion and determine its dependency on temperature distribution, temperature differential, initial flatness, and ripple length. Test results will be correlated with the analytical model and used to predict ripple growth in other plate-type fuel elements. The tests showed that ripple growth is dependent on initial flatness of the plate and that the characteristic shape of ripples is maintained at all temperature differentials: The tests also showed that the ripple growth rate for a ripple of 5 mil initial magnitude is approximately 0.12 mils/ deg F for a peak temperature differential of 103 deg F and that the apparent relationship between ripple net growth and length is 1.3 mil/in. of ripple for a peak temperature differential of 103 deg F. A permanent distortion of 2 mils for a complete temperature cycle from 0 to 103 to O deg F differential was found. The temperature profile across the plate width was found to affect the magnitude of ripple growth. (auth)
Date: June 27, 1962
Creator: Gebhardt, F. G.
Partner: UNT Libraries Government Documents Department
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Preliminary designs for ocean thermal energy conversion (OTEC) stationkeeping subsystems (SKSS). Task II. Conceptual design. Final report

Description: The study is presented in five sections: design loads, conceptual designs, trade studies, cost analysis and concept evaluation and ranking. Extensive appendixes provide back up calculations and data to support the results. Environmental forces and yaw moments acting on the barge and spar in the various design sea states are presented including wave, wind and current effects. A parametric analysis illustrates the impact on holding power requirement of varying the return periods for operational and extreme sea state. The conceptual designs are presented for the barge followed by those for the spar, including configuration definition, performance characteristics, interfaces, areas for development, and deployment scenarios for selected concepts. The concept definition is followed by a set of trade studies that were performed to evaluate candidate anchor types and anchor leg materials. Parametric variations in anchor leg characteristics, wire-rope-to-chain length ratio for example, illustrate the influence of the significant design parameters on performance. An extensive cost analysis of the candidate SKSS concepts is presented, including cost estimates, life cycle cost scenarios leading to expected value of life cycle cost, and cost equivalence of operational failures. An evaluation of the eight SKSS concepts is presented, including assessment of performance and rankings based on risk versus cost and technology development. The appendixes include a report on the Electrical Transmission System interface, wave drift force, typical cost disbursement schedule and computer program listing, the IMODCO conceptual design report, and static configuration results.
Date: July 27, 1979
Partner: UNT Libraries Government Documents Department
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The Peace Corps: Current Issues

Description: This report provides a brief overview of the Peace Corps and discusses how the 112th Congress is considering the President's annual funding request for the Peace Corps and efforts to reauthorize the Peace Corps. Current issues for Congress include the extent to which there is available funding for Peace Corps expansion, whether the Peace Corps has the institutional capacity to expand, and whether volunteers are able to function in a safe and secure environment.
Date: April 27, 2011
Creator: Tarnoff, Curt
Partner: UNT Libraries Government Documents Department
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Reaching the Debt Limit: Background and Potential Effects on Government Operations

Description: This report examines the possibility of the federal government reaching its statutory debt limit and not raising it, with a particular focus on government operations. First, the report explains the nature of the federal government's debt, the processes associated with federal borrowing, and historical events that may influence prospective actions. It also includes an analysis of what could happen if the federal government may no longer issue debt, has exhausted alternative sources of cash, and, therefore, depends on incoming receipts or other sources of funds to provide any cash needed to liquidate federal obligations. Finally this report lays out considerations for increasing the debt limit under current policy and what impact fiscal policy could have on the debt limit going forward.
Date: April 27, 2011
Creator: Levit, Mindy R.; Brass, Clinton T.; Nicola, Thomas J. & Shelton, Alison M.
Partner: UNT Libraries Government Documents Department
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Wildlife Impact Assessment and Summary of Previous Mitigation Related to Hydroelectric Projects in Montana, Phase I, Volume Two (A), Clark Fork Projects, Thompson Falls Dam, Operator, Montana Power Company.

Description: The Thompson Falls Dam inundated approximately 347 acres of wildlife habitat that likely included conifer forests, deciduous bottoms, mixed conifer-deciduous forests and grassland/hay meadows. Additionally, at least one island, and several gravel bars were inundated when the river was transformed into a reservoir. The loss of riparian and riverine habitat adversely affected the diverse wildlife community inhabiting the lower Clark Fork River area. Quantitative loss estimates were determined for selected target species based on best available information. The loss estimates were based on inundation of the habitat capable of supporting the target species. Whenever possible, loss estimates bounds were developed by determining ranges of impacts based on density estimates and/or acreage loss estimates. Of the twelve target species or species groups, nine were assessed as having net negative impacts. 86 refs., 2 figs., 5 tabs.
Date: March 27, 1984
Creator: Wood, Marilyn
Partner: UNT Libraries Government Documents Department
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Nuclear Analysis of Various Spert-III Critical Experiments

Description: Editor please delete 26456.<><DSN>16:026457<ABS>Work done in the P122 reactor control actuator area is summarized. Actuators were required to radially position the absorber blades in the core of the reactor. The P122C1 was a subsonic power plant and temperatures were low enough to permit the use of hydraulics in the actuator area. The program was reoriented and the power plant designated P122C3 which was a supersonic version of the folded flow power plant. The ambient temperature at maximum power was high enough to require pneumatic actuation of the control blades. The program was reoriented after two design iterations of the subsonic power plant. A test model of the actuating equipment and the entire linkage assembly was on hand and completed when the program was cancelled. The linkage was being redesigned for the supersonic application and special bearings were ordered for fabrication into the lower temperature rig. The actual mechanical concepts of the pneumatic actuator were under study when the program was cancelled. (auth)
Date: April 27, 1961
Creator: Paluszkiewicz, S.
Partner: UNT Libraries Government Documents Department
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