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Dislocation substructures in high-energy-rate-forged and press-formed 21-6-9 stainless steel

Description: A Transmission Electron Microscope (TEM) was used to establish that the substructure of press formed (PF) 21-6-9 stainless steel toroids was characterized by a dislocation cell size finer, about 0.16 ..mu..m, than that of about 0.29 ..mu..m, of high-energy-rate-formed (HERF) processed toroids. In addition, HERF processed material showed areas of a coarser, well-developed subgrain structure characteristic of hot work deformation. The formation of the substructures, as-well-as the grain size and carbide distributions of the toroids produced by the two processing techniques, are discussed in terms of the various operations, temperatures, and strain rates associated with the two different processing schedules. The Press-Formed toroid had a higher yield strength than the HERF processed toroid which was attributed to the finer cell size of the PF processed toroid.
Date: July 24, 1978
Creator: Sanderson, E.C.; Brewer, A.W.; Krenzer, R.W. & Krauss, G.
Partner: UNT Libraries Government Documents Department

OTEC platform configuration and integration. Volume III. Project Plan. Final report

Description: The Spar and Sphere offshore platforms are feasible concepts for the demonstration of a near full size OTEC plant to determine its validity and to gather data for use in the construction, design and operation of commercial OTEC plants. A hull size suitable to support a 100 MWe net output plant was chosen. Either 50, 25 or 12.5 MWe power modules could be used. Selection of 50 MWe modules would permit the testing of equipment recommended for the commercial plant. The use of 25 MWe modules would permit optimal hull volume utilization. The size hull selected for both platforms represents a reasonable increase above the pilot plant, providing design and construction problems similar to those that may be found in a hull size commercial plant. Since the hull size is substantially smaller than the projected commercial plant size, the possiblity of constructing the vessel of steel was presented. However, it is already determined that the full size hull shall be constructed principally of reinforced concrete and thus to fully demonstrate the feasibility of both construction techniques and operation, concrete was chosen for the demonstration plant. The superstructure of the sphere is all steel and for the spar, concrete with a steel deckhouse. The cold water pipe for both platforms is fiberglass. Construction of the hull and installation of all equipment are proposed to take place in three separate phases at three different sites. The overall plan proposes: (1) a shoreside construction site; (2) an offshore site in sufficient water depth to complete the hull erection; and (3) installation of the cold water pipe at the demonstration site.
Date: July 7, 1978
Partner: UNT Libraries Government Documents Department

Elemental sulfur analysis using x-ray techniques and. beta. -gauge mass measurements

Description: The activities funded under the present EPA/ERDA interagency agreement have been concentrated mainly in two areas. An elemental sulfur monitor for the measurement of fine particulates has been designed, constructed, and is currently being tested. A prototype of the device will be delivered in the near future. A second program has involved the development of the ..beta..-attenuation technique for the large-scale measurement of the masses of particulate deposits. The emphasis has been primarily concerned with the fabrication of improved hardware to perform the measurement conveniently and accurately. Other activities included consultation with EPA on questions concerning air sampling techniques and X-ray fluorescence analysis of aerosol samples. An additional long-term interest has been the development of X-ray techniques which are capable of determining the chemical form of the sulfur atoms in an environmental sample. Since these latter activities are in a more speculative period of development, the present progress report emphasizes the activities in the area of elemental sulfur monitoring and ..beta..-gauge development.
Date: July 1, 1977
Creator: Goulding, F.S.; Jaklevic, J.M. & Loo, B.W.
Partner: UNT Libraries Government Documents Department

Evaluation of a sulfur oxide chemical heat storage process for a steam solar electric plant

Description: The purpose of this study was to develop and evaluate technically feasible process configurations for the use of the sulfur oxide system, 2 SO/sub 3/ reversible 2 SO/sub 2/ + O/sub 2/, in energy storage. The storage system is coupled with a conventional steam-cycle power plant. Heat for both the power plant and the storage system is supplied during sunlit hours by a field of heliostats focussed on a central solar receiver. When sunlight is not available, the storage system supplies the heat to operate the power plant. A technically feasible, relatively efficient configuration is proposed for incorporating this type of energy storage system into a solar power plant. Complete material and energy balances are presented for a base case that represents a middle range of expected operating conditions. Equipment sizes and costs were estimated for the base case to obtain an approximate value for the cost of the electricity that would be produced from such an installation. In addition, the sensitivity of the efficiency of the system to variations in design and operating conditions was determined for the most important parameters and design details. In the base case the solar tower receives heat at a net rate of 230 MW(t) for a period of eight hours. Daytime electricity is about 30 MW(e). Nighttime generation is at a rate of about 15 MW(e) for a period of sixteen hours. The overall efficiency of converting heat into electricity is about 26%. The total capital cost for the base case is estimated at about $68 million, of which about 67% is for the tower and heliostats, 11% is for the daytime power plant, and 22% is for the storage system. The average cost of the electricity produced for the base case is estimated to be about 11 cents/kW(e)-hr.
Date: July 1, 1979
Creator: Dayan, J.; Lynn, S. & Foss, A.
Partner: UNT Libraries Government Documents Department

Solar thermal small power systems study, program summary report. Phase II: study results

Description: This Phase II Study of small solar power systems (SSPS) has been structured to determine conditions under which SSPS can be cost-effective sources of electric power in the US in the period 1985 to 2015. An extensive data base, which provides a discrete identification of all utility and industrial electric generating units up to and including 10 MW/sub e/ in rated capacity, has been prepared. This data base defines the market for which comparative evaluations are made of SSPS and alternative fossil-fueled power plants. The market penetration of SSPS is determined and the effect of economic incentives on accelerating the penetration is evaluated. The solar electric power system is evaluated as either a complete replacement for existing conventional electric power systems or as a repowering installation for boilers supplying steam to turbine-driven generators. The cost data used in the market penetration analysis are for a central receiver-type of small solar theral power system. While the market penetration discussed herein is for this type of SSPS, the sensitivity data in the report can be used to determine the market penetration of other types of solar thermal power systems (e.g., point focus distributed receiver) with different system costs.
Date: July 12, 1979
Creator: Lapedes, D.E.; Munjal, P.K. & Sitney, L.R.
Partner: UNT Libraries Government Documents Department

Thin films of gallium arsenide on low-cost substrates. Quarterly technical progress report No. 8 and topical report No. 3, April 2-July 1, 1978

Description: The seventh quarter of work on the contract is summarized. The metalorganic chemical vapor deposition (MO-CVD) technique has been applied to the growth of thin films of GaAs and GaAlAs on inexpensive polycrystalline or amorphous substrate materials (primarily glasses and metals) for use in fabrication of large-area low-cost photovoltaic device structures. Trimethylgallium (TMG), arsine (AsH/sub 3/), and trimethylaluminum (TMAl) are mixed in appropriate concentrations at room temperature in the gaseous state and pyrolyzed at the substrate, which is heated in a vertical reactor chamber to temperatures of 725 to 750/sup 0/C, to produce the desired film composition and properties. The technical activities during the quarter were concentrated on (1) a continuing evaluation of various graphite materials as possible substrates for MO-CVD growith of the polycrystalline GaAs solar cells; (2) attempts to improve the quality (especially the grain size) of polycrystalline GaAs films on Mo sheet and Mo/glass substrates by using HCl vapor during the MO-CVD growith process; (3) further studies of the transport properties of polycrystalline GaAs films, wth emphasis on n-type films; (4) continuing investigations of the properties of p-n junctions in polycrystalline GaAs, with emphasis on the formation and properties of p/sup +//n/n/sup +/ deposited structures; and (5) assembling apparatus and establishing a suitable technique for producing TiO/sub 2/ layers for use as AR coatings on GaAs cells. Progress is reported. (WHK)
Date: July 1, 1978
Creator: Ruth, R.P.; Dapkus, P.D.; Dupuis, R.D.; Johnson, R.E.; Manasevit, H.M.; Moudy, L.A. et al.
Partner: UNT Libraries Government Documents Department

Commercial applications of solar total energy systems. Volume 3. Conceptual designs and market analyses. Final report

Description: The overall objective of this program was to assess the feasibility of using solar energy to provide a significant fraction of the energy needs of commercial buildings that have energy demands greater than 200 kWe. The STES concept trade studies, sensitivity parameters, performance characteristics, and selected concepts are discussed. Market penetration rate estimates are provided, and technology advancements and utilization plans are discussed. Photovoltaic STES configurations and Rankine cycle thermal STES systems are considered. (WHK)
Date: July 1, 1978
Creator: Boobar, M.G.; McFarland, B.L.; Nalbandian, S.J.; Willcox, W.W.; French, E.P. & Smith, K.E.
Partner: UNT Libraries Government Documents Department

Study of air pollution scavenging. Fifteenth progress report. [Air pollution over St. Louis, Missouri and rural Illinois]

Description: Selected analyses of air and rainwater chemistry and meteorological data are presented as part of the final efforts on the 5-year METROMEX study. The size characterization, air concentration, and source identification of aerosols over and near St. Louis are related to the urban-industrial activities of the metropolitan area. The precipitation studies are comprised of a comparison of chemical analyses of simulated rain samples between several laboratories, including the Survey. The results showed that the analytical technique used by the Survey for the chemical analysis of the METROMEX samples is excellent for increasing confidence in the published data. Other precipitation analyses are directed toward the acid rain problem as demonstrated by historical and current measurements in Illinois. The meteorological investigations consist of analysis of diurnal temperature and moisture cycles at urban and rural sites which relates to the development of the planetary boundary layer (PBL) as perturbed by the city. The three-dimensional character of the PBL is also presented as determined by the radiosonde operations during METROMEX. Finally, the technique to calculate three-dimensional trajectories of air motion using the numerous pilot balloon observations acquired during the project is presented. These data are essential for the full interpretation of the air and rain chemistry observations, and the development of empirical models of pollutant scavenging.
Date: July 1, 1977
Creator: Semonin, R. G.; Ackerman, B.; Gatz, D. F.; Rilberg, S. D.; Peden, M. E.; Stahlhut, R. K. et al.
Partner: UNT Libraries Government Documents Department

Quality engineering and control semiannual progress report November and December 1976 and January--April 1977

Description: Research and development activities are reported on absorption spectroscopy, calorimetry, electrolysis, emission spectroscopy, fluorimetry gas chromatography, infrared spectroscopy, liquid chromatography, liquid scintillation counting, mass spectroscopy, microscopy, radiometric analysis, and thermal analysis. A group of miscellaneous projects are also described. (JRD)
Date: July 14, 1977
Creator: Carpenter, R. L.
Partner: UNT Libraries Government Documents Department

Correlation of substructure with mechanical properties of plastically deformed reactor structural materials. Progress report, January 1, 1976--June 30, 1977

Description: Transmission electron microscopy used to evaluate the deformation (creep, fatigue and tensile) induced microstructure of 304 SS, Incoloy 800, 330 SS and three of the experimental alloys (E19, E23 and E36) obtained from the National Alloy Program clearly shows that the relationship between the subgrain size (lambda) and the applied stress (sigma) obeys the equation lambda = Ab (sigma/E)/sup -1/ where A is a constant of the order of 4, b the Burgers rector and E is Young's modulus. Hot-hardness studies on 304 SS, 316 SS, Incoloy 800, 2 /sup 1///sub 4/ Cr-1 Mo steels, 330 SS, Inconel 718, PE-16, Inconel 706, M-813 and the above three experimental alloys suggests that reasonable effective activation energies for creep may be obtained through the use of the hardness test as a strength microprobe tool. The ordering of the strength levels obtained through hot-hardness follows quite closely that obtained in tensile tests when those data are available.
Date: July 8, 1977
Creator: Moteff, J.
Partner: UNT Libraries Government Documents Department

Enhanced filtration program at LLL. A progress report

Description: As part of Lawrence Livermore Laboratory's Enhanced Filtration Program, we are investigating the use of an externally applied electric field to improve the performance of fibrous filters. Our objective in this program is to develop filtration systems for the nuclear industry that will reduce the cost and volume of nuclear waste associated with present systems. We have developed a new theory of the electrostatic filter that is consistent with experimental tests made during transient and steady-state conditions. For these tests, we used ac and dc electric fields, insulated and noninsulated electrodes, and conducting and nonconducting filter media; all tests were conducted in our small-scale 25 l/s test system, using sodium chloride aerosols. Our theory employs a new mechanism based on the attraction between charged particles and charged fibers in addition to the previously proposed mechanism based on the attraction between charged particles and polarized fibers. In this theory, fibers are charged when charged particles deposit on them. We have also developed a theoretical model that explains the increase in filter efficiency and pressure drop when particles load on the filter. The filter loading tests we conducted to evaluate this model verify its accuracy to a remarkable degree. By using the model equations, we are thus able to explain the observed increase in filter efficiency as a function of particle mass loading, particle size, and particle-particle collection efficiency. Two systems we developed for use in the nuclear industry use electric fields to increase the performance of fibrous filters. One is designed for use inside glove boxes to control radioactive particles at their source; the other is designed for use in ventilation systems. Here we report the results of laboratory and field evaluations for the glove box system.
Date: July 28, 1978
Creator: Bergman, W.; Taylor, R.D.; Miller, H.H.; Bierman, A.H.; Hebard, H.D.; daRoza, R.A. et al.
Partner: UNT Libraries Government Documents Department

High-temperature electronics workshop: progress in the development of microelectronics for the 500/sup 0/C environment

Description: This workshop proceedings describes the status of the Los Alamos Scientific Laboratory (LASL) and University of Arizona programs in the development of high-temperature microelectronic devices for geothermal well-logging applications.
Date: July 1, 1978
Creator: McCormick, J.B. (ed.)
Partner: UNT Libraries Government Documents Department

Desulfurization of coal-derived pyrite using solutions containing dissolved oxygen.

Description: The effect of alkaline solutions containing dissolved oxygen on coal-derived pyrite was investigated in a tubular reactor. The rate of total sulfur conversion seems to be affected by oxygen partial pressure, oxygen flow rate, particle size, pyrite charge size and system temperature. A shrinking core model was chosen to represent this chemical leaching process. From the results obtained, it seems that ash or product-layer difusion is the rate-limiting step for leaching with the alkaline solution/oxygen system. The effective diffusivity is about 10/sup -5/ cm/sup 2//sec. The apparent activation energy for this process is 7.97 kcal/mole in the temperature range from 121/sup 0/ to 175/sup 0/C. For the tubular reactor system used, the rate of sulfur extraction appears to be proportional to the oxygen partial pressure. The rate of conversion increases as the oxygen flow rate decreases to a limit of 3 ml/sec. The rate also increases as the pyrite charge size decreases. The leaching solutions flow rate has a negligible effect on the total sulfur conversion.
Date: July 1, 1979
Creator: Chen, M. C.
Partner: UNT Libraries Government Documents Department

/sup 3/He release from UT/sub 3/

Description: Recent Mound Laboratory data for the temperature and particle size dependence of /sup 3/He release from UT/sub 3/ are summarized. The quasi steady-state /sup 3/He early release rate is shown to increase with increasing specific surface area, and the /sup 3/He release characteristics are shown to be temperature insensitive near 25/sup 0/C. A qualitative model for /sup 3/He mobility in UT/sub 3/ is proposed, and an estimate of the /sup 3/He migration energy is made.
Date: July 1, 1976
Creator: Wilson, K. S.; Malinowski, M. W. & Baskes, M. I.
Partner: UNT Libraries Government Documents Department

Characterization of Kevlar-49 yarn

Description: A study was made to determine the variability in Dupont's 380-denier Kevlar-49 yarn. Both in-spool and spool-to-spool variations in tensile strength, cross-sectional area, and chemical composition were determined for one lot of material.
Date: July 1, 1978
Creator: Thompson, W.F.; Powell, G.L. & Lever, W.E.
Partner: UNT Libraries Government Documents Department

Applications of the probability table method to practical problems. [Suitability of ALICE code]

Description: The objective of using the probability table method (PTM) was to use a continuous-energy Monte Carlo code in which the cross sections are given as multigroup constants and yet to account for self-shielding within each group. In order to achieve this objective, the PTM was extended to deterministic methods. The ALICE Monte Carle Neutron Transport Code uses the PTM for all 175 energy groups which span the energy range from thermal to 20 MeV. The TART, ALICE, and MCN codes were used to determine the critical radius of a sphere of UH/sub 3/, where the U/sup 235/ enrichment varied from 20 to 100%. The PTM was used to calculate the transmission through a 30 cm iron plate. The source was normal to the slab and distributed as 1.0/E from 20.0 MeV to 1 keV. For the problems investigated the ALICE code can calculate both shielding and criticality problems as accurately as the pointwise code MCN. 1 figure, 1 table. (RWR)
Date: July 1, 1977
Creator: Plechaty, E. F.; Cullen, D. E. & Levitt, L.
Partner: UNT Libraries Government Documents Department

Appraisal study of the geothermal resources of Arizona and adjacent areas in New Mexico and Utah and their value for desalination and other uses

Description: An appraisal investigation of the geothermal resources of a portion of the Lower Colorado River Region of the U.S. Bureau of Reclamation is reported. The study area includes most of Arizona, part of western New Mexico west of the continental divide, and a small part of southwestern Utah. Almost 300 water samples have been collected from the study area and chemically analyzed. These samples include hot wells and springs in addition to nearby nonthermal waters to help establish background chemistry. Further, almost 10,000 chemical analyses of groundwaters were obtained from the U.S. Geological Survey's water quality file. Routine geothermal interpretative techniques were then applied to these chemical data to identify geothermal anomalies which might indicate the presence of exploitable geothermal resources. These geochemical anomalies were then evaluated in terms of available geophysical data such as heat flow, gravity, magnetics, basement linears, earthquake epicentral locations, depth of sedimentary basins, quaternary volcanics, recent fault scarps, etc. to further delineate the size and shape of the prospective geothermal sites and help establish their production potential.
Date: July 1, 1977
Creator: Callender, J.F.; Swanberg, C.A.; Morgan, P.; Stoyer, C.H. & Witcher, J.C.
Partner: UNT Libraries Government Documents Department

Nickel-free Fe-12Mn-0. 2Ti alloy steel for cryogenic applications

Description: A nickel-free Fe-12 Mn-0.2 Ti alloy steel was investigated for cryogenic applications. The systematic control of the grain size and the microstructural distribution of the retained ..gamma.. phase was made through ..cap alpha.. + ..gamma.. heat treatments in combination with mechanical working. Substantial improvements of important low temperature mechanical properties were obtained by these processings. Our results indicated a good possibility of developing a new, inexpensive cryogenic steel.
Date: July 1, 1976
Creator: Hwang, S.; Jin, S. & Morris, J. W. Jr.
Partner: UNT Libraries Government Documents Department

Structure of a black chrome solar selective surface

Description: The structure of ''CHROM-ONYX'' type of black chrome/metal selective absorber was studied to gain a better understanding of its influence upon the mechanism of wavelength selectivity. Spectral reflectance measurements were performed on seven samples. The best selectivity was found by these measurements to be 0.7 micron of black chrome on nickel and 1.0 micron of black chrome on copper. Both scanning and transmission electron microscopy were employed to study microstructure and chemical composition. As a result of the combined studies, some effects of black chrome thickness and the metallic substrate were determined. It was found that black chrome consisted of a very fine metallic distribution of particles of chromium, possibly suspended within a matrix of an oxide of chromium. This combination was, in turn, agglomerated into larger particles within the 0.05 to 0.3 micron size range. These larger particles formed a network which constituted the surface coating.
Date: July 1, 1978
Creator: Lampert, C.M.
Partner: UNT Libraries Government Documents Department

Evaluation of selected chemical processes for production of low-cost silocon. (Phases I and II. ) Final report, October 9, 1975--July 9, 1978. Silicon Material Task, Low-Cost Solar Array Project

Description: The zinc reduction of silicon tetrachloride in a fluidized bed of seed particles to yield a granular product was studied along with several modifications of the thermal decomposition or hydrogen reduction of silicon tetraiodide. Although all contenders were believed to be capable of meeting the quality requirements of the LSA Project, it was concluded that only the zinc reduction of the chloride could be made economically feasible at a cost below $10/kg silicon (1975 dollars). Accordingly, subsequent effort was limited to evaluating that process. A miniplant, consisting of a 5-cm-diameter fluidized-bed reactor and associated equipment was used to study the deposition parameters, temperature, reactant composition, seed particle size, bed depth, reactant throughput, and methods of reactant introduction. It was confirmed that the permissible range of fluidized-bed temperature was limited at the lower end by zinc condensation (918 C) and at higher temperatures by rapidly decreasing conversion efficiency (by 0.1 percent per degree C from 72 percent (thermodynamic) at 927 for a stoichiometric mixture). Use of a graded bed temperature was shown to increase the conversion efficiency over that obtained in an isothermal bed. Other aspects of the process such as the condensation and fused-salt electrolysis of the ZnCl/sub 2/ by-product for recycle of zinc and chlorine were studied to provide information required for design of a 50 MT/year experimental facility, visualized as the next stage in the development. Projected silicon costs of $7.35 and $8.71 per kg (1975 dollars) for a 1000 MT/year facilitywere obtained, depending upon the number and size of the fluidized-bed reactors and ZnCl/sub 2/ electrolytic cells used. An energy payback time of 5.9 months was calculated for the product silicon.
Date: July 9, 1978
Creator: Blocher, J.M. Jr. & Browning, M.F.
Partner: UNT Libraries Government Documents Department

Wind erosion research at an uranium mill tailings site

Description: A uranium mill tailings pile at Grants, New Mexico, was selected for wind erosion research since the configuration provides flat area containing fine sand and made up of larger particles. The wind erosion experiment is discussed. Experimental equipment consists of meteorological instrumentation to automatically activate air samplers as a function of wind speed increments and direction, particle cascade impactors to measure airborne respirable concentrations as a function of particle size, inertial impaction devices to measure nonrespirable fluxes of airborne particles, a virtual particle cascade impactor to measure airborne concentrations of toxic trace elements, and soil depth gauges to measure changes in surface soil elevations as a function of time. Both radioactive particles as well as toxic trace element concentrations are measured. Radioactive particles are measured with both particle cascade impactors as well as high-volume air samplers. In contrast, toxic trace element airborne concentrations are measured only with a two-stage virtual particle cascade impactor. Fluxes of nonrespirable airborne particles are measured with inertial impaction devices. At particle cascade impactor sites, a rotating cyclone preseparator collects nonrespirable particles. In addition at all sites, fluxes of nonrespirable particles are measured using an open cavity inertial impaction device. (JGB)
Date: July 1, 1977
Creator: Sehmel, G.A.
Partner: UNT Libraries Government Documents Department

Apparatus for the field evaluation of geothermal effluent injection

Description: Methods for evaluating subsurface disposal systems, based on data derived from membrane filtration tests and core flooding experiments, have been described in the literature. These techniques were used to develop and successfully test equipment for evaluation of injectability of any geothermal effluent including hypersaline brine from the Salton Sea Geothermal Field. A schematic diagram of the prototype system for filtration and core flooding is included.
Date: July 1, 1978
Creator: Netherton, R. & Owen, L.B.
Partner: UNT Libraries Government Documents Department