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Peregrine Falcon study. Final report (open access)

Peregrine Falcon study. Final report

Three papers are included. A separate abstract was prepared for each. (MHR)
Date: February 1, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Boundary element formulation for planar time-dependent inelastic deformation of plates with cutouts (open access)

Boundary element formulation for planar time-dependent inelastic deformation of plates with cutouts

A boundary element formulation for planar, time-dependent, inelastic deformation problems for bodies with cutouts is presented in this paper. A stress function description for these nonlinear problems leads to a nonhomogeneous biharmonic equation for the stress function rate. An integral representation of the solution uses modified kernels which guarantee that the cutout boundary is traction free for all time. This incorporation of the effect of the cutout on the stress field into the kernels leads to an accurate determination of stresses in the near field of the cutout. Illustrative analytical examples for circular plates with circular cutouts are presented in this paper. In a companion paper, numerical solutions are presented for problems of finite plates with very narrow elliptic cutouts. These problems are of considerable importance in inelastic fracture.
Date: February 1, 1980
Creator: Mukherjee, S. & Morjaria, M.
Object Type: Report
System: The UNT Digital Library
Silicon mass transfer in sodium loops and the resulting/thermal hydraulic effects. [LMFBR] (open access)

Silicon mass transfer in sodium loops and the resulting/thermal hydraulic effects. [LMFBR]

The element silicon in the surface of new, 300 series stainless steel has been shown to rapidly dissolve in sodium above 525/sup 0/C. It deposits in slightly cooler regions as a crystalline compound with sodium and oxygen. In tests, the deposits have caused increases in hydraulic friction factor (hence, increased pressure loss) of up to 300% at Reynolds Numbers of 14/sup 4/ to 10/sup 5/.Also, they have contributed to local losses of heat transfer rate to 1/10 the original value, at a Reynolds Number of approximately 10/sup 4/. The crystals quickly decompose when out of sodium. Measurements made with a sodium loop (volume = 0.42 m/sup 3/) include compound solubility vs temperature, loop conditions vs source rates and deposit transfer rates. Laboratory examinations and analyses of the crystals have also been made. The effects of this material have been observed also in a number of other loops. With the data from these studies, such effects are now explained and can be controlled or eliminated by system design and operation.
Date: February 1, 1980
Creator: Yunker, W.H.
Object Type: Article
System: The UNT Digital Library
Assessment of the potential of colloidal fuels in future energy usage. Final report. [97 references] (open access)

Assessment of the potential of colloidal fuels in future energy usage. Final report. [97 references]

Pulverized coal has been an increasing important source of energy over the past century. Most large utility boilers, all modern coking plants, and many industrial boilers and blast furnaces employ pulverized coal as a major feed stream. In periods of oil shortages, such as during World Wars I and II, the concept of adding powdered coal to oil for use in combustion equipment originally designed for oil has been actively pursued but rarely used. Over this same period of time, there have been attempts to use air suspensions of coal dust in diesel engines in Germany, and in turbines in various countries. The economic advantages to be enjoyed by substitution of powdered coal in oil are not generally realized. Oil costs at $30/bbl represent a fuel value of about $5.00/10/sup 6/ Btu; coal at $25/ton is equivalent to approximately $1.00/10/sup 6/ Btu. Although capital costs for the use of coal are higher than those associated with the use of oil, coal is clearly becoming the least costly fuel. Not only are considerable cost advantages possible, but an improvement in balance of payments and an increase in reliability of fuel supplies are other potential benefits. It is therefore recommended that increased …
Date: February 25, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
HC quench layer formation in combustion processes. Technical progress report, September-December 1979 (open access)

HC quench layer formation in combustion processes. Technical progress report, September-December 1979

The project is aimed at understanding wall quenching and other processes responsible for surface generated hydrocarbons in combustion under engine-like conditions. The study concerns the effects of turbulence on the evolution of hydrocarbons. At the conclusion of the program, significant new experimental information will have been generated and an analytical model of the fluid mechanics and some aspects of the chemistry of quenching will be formulated. The work is divided into three tasks: (1) combustion bomb experiments to measure the effect of turbulence on the chemical species near the cold surface; combustion bomb experiments, using a similar turbulence generating device, to fully characterize the flow and turbulence in the vicinity of the quenching surface, and an analytical study to characterize fluid mechanical scales of interest in the boundary layer and to find an analytical solution to describe the evolution of the layer. The major accomplishments to date are (i) demonstration of the feasibility of single shot sampling valve operation and gas analysis in the Ford bomb under laminar combustion conditions, (ii) formulation of design rationale for turbulence generation scheme and bomb geometry, and (iii) formulation of an approach to modeling turbulent boundary layer conditions.
Date: February 1, 1980
Creator: Lavoie, G. A.
Object Type: Report
System: The UNT Digital Library
Study of aluminum corrosion in aluminum solar heat collectors using aqueous glycol solution for heat transfer. Semiannual technical progress report, July 30, 1979-January 31, 1980 (open access)

Study of aluminum corrosion in aluminum solar heat collectors using aqueous glycol solution for heat transfer. Semiannual technical progress report, July 30, 1979-January 31, 1980

The present work is addressed primarily to the study of the effects of glycol aging at elevated temperatures (above 100/sup 0/C). Glycols are known to be susceptible to thermal decomposition producing new product species which may be aggressive to aluminum. In addition, the possible breakdown of corrosion inhibitors due to long term exposure to high temperature are also investigated. Both uninhibited and inhibited ethylene (as well as propylene) glycols have been aged at temperatures up to 190/sup 0/C for over 2000 h continuously to date. Aliquot samples of each glycol solution tested in this program were taken at 1000 and 2000 h of exposure for chemical analysis and pH measurement. Based on the data obtained so far, solution pH was found to decrease steadily with exposure time. The critical pitting potential of 1100 series aluminum in a 50 vol % aqueous ethylene glycol solution is reported as functions of both temperature and chloride ion concentration. This information is essential in the cathodic protection of pitting corrosion of aluminum.
Date: February 1, 1980
Creator: Wong, D.; Cocks, F.H. & Giner, J.
Object Type: Report
System: The UNT Digital Library
Gas-cooled fast breeder reactor. Quarterly progress report, November 1, 1979 through January 31, 1980 (open access)

Gas-cooled fast breeder reactor. Quarterly progress report, November 1, 1979 through January 31, 1980

Information is presented concerning the nuclear steam supply system; reactor core; systems engineering; safety and reliability; and circulator test facility.
Date: February 1, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Assessment of environmental health and safety issues associated with the commercialization of unconventional gas recovery: Tight Western Sands (open access)

Assessment of environmental health and safety issues associated with the commercialization of unconventional gas recovery: Tight Western Sands

Results of a study to identify and evaluate potential public health and safety problems and the potential environmental impacts from recovery of natural gas from Tight Western Sands are reported. A brief discussion of economic and technical constraints to development of this resource is also presented to place the environmental and safety issues in perspective. A description of the resource base, recovery techniques, and possible environmental effects associated with tight gas sands is presented.
Date: February 1, 1980
Creator: Riedel, E.F.; Cowan, C.E. & McLaughlin, T.J.
Object Type: Report
System: The UNT Digital Library
Effects of Prudhoe Bay crude oil in sediment on Abarenicola pacifica in laboratory and field experiments (open access)

Effects of Prudhoe Bay crude oil in sediment on Abarenicola pacifica in laboratory and field experiments

Behavioral responses of organisms are often sensitive indicators of changes in the environment over short time frames. The rate of burrowing of Abarenicola pacifica, a lugworm typical of muddy tidal flats, was studied to determine its response to the presence of hydrocarbons in the environment. If a reduction in burrowing rates is reflected in reduced food intake, a decline in nutritional status might be expected. The level of free amino acids in the tissues was examined as a possible indicator of nutritional status. (ACR)
Date: February 1, 1980
Creator: Augenfeld, J.M.
Object Type: Report
System: The UNT Digital Library
MHD Coal-Fired Flow Facility. Quarterly/annual technical progress report, October-December 1979 (open access)

MHD Coal-Fired Flow Facility. Quarterly/annual technical progress report, October-December 1979

In this Fourth Quarterly/Annual Report submitted under DOE contracts EX-76-C-01-1760 and DE-AC02-79ET10815, the University of Tennessee Space Institute (UTSI) reports on significant activity, task status, planned research, testing, and development, and conclusions for the Magnetohydrodynamics (MHD) Coal-Fired Flow Facility (CFFF) and the Research and Development Laboratory. Work on the CFFF progressed with only minor problems. Total construction activity for all site work presently awarded is nearly 98% complete. Water analysis shows that Woods Reservoir baseline conditions are within EPA or Tennessee drinking water standards. For the primary combustor, the vitiation heater and primary combustor fabrication drawings were completed and the nozzle design was completed. The drum module for the radiant slagging furnace was awarded. On the MHD Power Generator, development continued in several areas of advanced analysis including development of time-dependent models for use with the one-dimensional code. For seed regeneration, the tentative determination is that the Tomlinson Tampella is the most economically viable method. With regard to capped electrode erosion, investigations have shown that the major degradation of the cladding still present is at the leading edge of the capped anode. To alleviate this, plans are to hot work the noble metal in the bending operation. In resolving another …
Date: February 1, 1980
Creator: Dicks, J. B.; Chapman, J. N. & Crawford, L. W.
Object Type: Report
System: The UNT Digital Library
Fundamental characterization of alternate fuel effects in continuous combustion systems. Summary technical progress report, August 15, 1978-January 31, 1980 (open access)

Fundamental characterization of alternate fuel effects in continuous combustion systems. Summary technical progress report, August 15, 1978-January 31, 1980

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 …
Date: February 27, 1980
Creator: Blazowski, W.S.; Edelman, R.B. & Wong, E.
Object Type: Report
System: The UNT Digital Library
Role of organic soils in the world carbon cycle: problem analysis and research needs (open access)

Role of organic soils in the world carbon cycle: problem analysis and research needs

In May 1979, The Institute of Ecology held a workshop to determine the role of organic soils in the global carbon cycle and to ascertain their past, present and future significance in world carbon flux. Wetlands ecologists and soil scientists who participated in the workshop examined such topics as Soils as Sources of Atmospheric CO/sub 2/, Organic Soils, Primary Production and Growth of Wetlands Ecosystems, and Management of Peatlands. The major finding of the workshop is that the organic soils are important in the overall carbon budget. Histosols and Gleysols, the major organic soil deposits of the world, normally sequester organic carbon fixed by plants. They may now be releasing enough carbon to account for nearly 10% of the annual rise in atmospheric content of CO/sub 2/.
Date: February 1, 1980
Creator: Armentano, T.V. (ed.)
Object Type: Article
System: The UNT Digital Library
Geological Interpretation of Self-Potential Data From the Cerro Prieto Geothermal Field (open access)

Geological Interpretation of Self-Potential Data From the Cerro Prieto Geothermal Field

A source mechanism based on concepts of irreversible thermodynamics and consisting of heat or fluid flow along a north-south trending zone of faulting is proposed for the self-potential anomaly measured over the Cerro Prieto geothermal reservoir. The source region is represented by a vertical plane of that separates regions of differing streaming potential or thermoelectric coupling coefficients. The coupling coefficient contrast could be caused by vertical offset of rock units along faults. The depth to the top of the source plane is about 1.3 km, its vertical extent is about 11 km, and its length along strike is about 10 km. Geological, geophysical, and mineralogical evidence supports the existence of an important north-south geological trend roughly corresponding in location to the proposed self-potential source plane.
Date: February 1, 1980
Creator: Corwin, R. F. & Fitterman, D. V.
Object Type: Article
System: The UNT Digital Library
Radioactivity in gaseous waste discharged from the separations facilities during fourth quarter of 1979 (open access)

Radioactivity in gaseous waste discharged from the separations facilities during fourth quarter of 1979

This document is issued quarterly for the purpose of summarizing the radioactive gaseous wastes that are discharged from the facilities of the Rockwell Hanford Operations (Rockwell). Data on alpha and beta emissions during 1979 are presented where relevant to the gaseous effluent. Emission data are not included on gaseous wastes produced within the 200 areas by other Hanford contractors.
Date: February 22, 1980
Creator: Sliger, G. J.
Object Type: Report
System: The UNT Digital Library
Documentation of Volume Three of the 1978 Energy Information Administration Annual Report to Congress (open access)

Documentation of Volume Three of the 1978 Energy Information Administration Annual Report to Congress

The purpose of the ARC78 forecasts and the ways in which they differ from those in the ARC77 are discussed. In a preliminary overview of the projection process, the relationship between energy prices, supply, and demand is addressed. Topics treated in detail include a description of energy-economic interactions, assumptions regarding world oil prices, and energy modeling in the long term beyond 1995. Subsequent sections present the general approach and methodology underlying the forecasts, and define and describe the alternative projection series and their associated assumptions. Short-term forecasting, midterm forecasting, long-term forecasting of petroleum, coal, and gas supplies are included. The role of nuclear power as an energy source is also discussed.
Date: February 29, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Modular OTEC platforms, SKSS designs. Volume I. Executive summary. Final report (open access)

Modular OTEC platforms, SKSS designs. Volume I. Executive summary. Final report

One of the possible options for generating electrical energy from ocean thermal gradients requires the use of a floating offshore platform. The platform would contain all OTEC (Ocean Thermal Energy Conversion) systems and power cycle components and consist of the hull, seawater, station-keeping, platform service, and mission support subsystems. It would be stationed at one of the designated OTEC sites, and would transmit the generated electricity to the shore power networks by means of an electrical transmission cable. The objective of the present study is to investigate the station-keeping subsystem (SKSS) requirements and develop preliminary SKSS designs for the two Modular Experiment Plant (MEP) candidates of 10/40 MW/sub e/ capacity for deployment at a specific site. The two MEP hull candidates are a Barge type platform and a Spar shaped hull with external heat exchangers. The specific site assigned for this study is Puerto Rico. The preliminary SKSS designs are developed for both platforms as follows: (1) an 8-leg spread catenary mooring system for the Spar, and (2) a 12-leg spread catenary mooring system for the Barge. Applicability of these designs to larger capacity commercial OTEC platforms is also investigated.
Date: February 29, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Cadmium sulfide/copper sulfide heterojunction cell research. Technical progress report, September 1-November 30, 1979 (open access)

Cadmium sulfide/copper sulfide heterojunction cell research. Technical progress report, September 1-November 30, 1979

Several all sputter deposited Cu/sub 2/S/CdS cells have been prepared to date with J/sub SC/ approx. = 3 mA/cm/sup 2/ under simulated AM1 illumination. The best AM1 conversion efficiency obtained is 0.6%. This is shown to be typical of sputtered CdS in Cu/sub 2/S/CdS cells investigated to date. The sputtered Cu/sub 2/S appears to be satisfactory for solar cell applications. Presented evidence indicates that the poor conversion efficiency is due to a low-junction electric field intensity on the CdS side of the heterojunction. A multilayer CdS structure has been developed which may allow the tailoring of the junction electric field intensity to a selected high value to obtain high-junction collection efficiency. Other areas of cell development advances included: (1) determination of effect of Cu cones in Cu/sub 2/S on Cu/sub 2/S/CdS cell performance; (2) solution of CdS pinhole problem; and (3) open circuit voltage improvement by heat treatment.
Date: February 1, 1980
Creator: Anderson, W. W. & Jonath, A. D.
Object Type: Report
System: The UNT Digital Library
Reliability considerations of electronics components for the deep underwater muon and neutrino detection system (open access)

Reliability considerations of electronics components for the deep underwater muon and neutrino detection system

The reliability of some electronics components for the Deep Underwater Muon and Neutrino Detection (DUMAND) System is discussed. An introductory overview of engineering concepts and technique for reliability assessment is given. Component reliability is discussed in the contest of major factors causing failures, particularly with respect to physical and chemical causes, process technology and testing, and screening procedures. Failure rates are presented for discrete devices and for integrated circuits as well as for basic electronics components. Furthermore, the military reliability specifications and standards for semiconductor devices are reviewed.
Date: February 1, 1980
Creator: Leskovar, B.
Object Type: Article
System: The UNT Digital Library
Development of copper sulfide/cadmium sulfide thin film solar cells. First technical progress report, 13 July 1979 to 12 October 1979 (open access)

Development of copper sulfide/cadmium sulfide thin film solar cells. First technical progress report, 13 July 1979 to 12 October 1979

Preparation of CdS films by evaporation from a single graphite source, as generally used by the Institute of Energy Conversion (IEC) group at the University of Delaware, has been implemented. Previously at Westinghouse, four evaporation sources were used to permit uniform coverage of large area substrates. The graphite source used in this period is somewhat smaller than the IEC design to permit accommodation to the heater geometry currently available. Initial efforts with the single source evaporation have been on characterizing the thickness profiles of the deposited films. This is needed to permit selection of conditions for obtaining films of about 30..mu..m thickness over the central 4 cm x 4 cm area of the substrate. Barrier processing according to the details of IEC method has been used on four-source CdS films. To date the best cells have only been about 1% efficient. Low short circuit current density values (approx. 5 mA/cm/sub 2/) have been the biggest problem. Annealing in 6% H/sub 2//Ar mixtures at 170/sup 0/C after electrode grid evaporation generally has resulted in reduced values of J/sub sc/. Plans for the next period include the use of single source films for cell processing and the use of small area diode …
Date: February 14, 1980
Creator: Szedon, J. R.; Shirland, F. A.; Stoll, J. A. & Dickey, H. C.
Object Type: Report
System: The UNT Digital Library
Sequential purification and crystal growth for the production of low cost silicon substrates. Quarterly technical progress report No. 1, 15 September 1979-31 December 1979 (open access)

Sequential purification and crystal growth for the production of low cost silicon substrates. Quarterly technical progress report No. 1, 15 September 1979-31 December 1979

Over the past several years, Motorola's Materials Technology Laboratory (MTL), has been conducting several projects with goals directed at the production of high quality low cost silicon crystals. One of the projects which is being investigated is the direct purification of MG-Si. A unique characteristic of the approach used by this project is the use of a crystal puller to perform both purification and crystal growth. Sequential steps of purification were taken. By the completion of this series of purification, the purified MG-Si melt will be further purified by impurity redistribution using ingot pulling. The final purified silicon will be in an ingot form of desired dimensions for slicing into silicon sheets. The sequential steps of purification include: (1) leaching of MG-Si charge, (2) phase separation, (3) reactive gas treatment, (4) liquid-liquid extraction (called Slagging), and (5) purification by redistribution of impurities using ingot pulling. Progress on items (1) and (2) is reported. (WHK)
Date: February 1, 1980
Creator: Liaw, M.; Secco, F.; Ingle, B. & Down, D.
Object Type: Report
System: The UNT Digital Library
Biological conversion of biomass to methane. Final report, June 1, 1976-January 31, 1980 (open access)

Biological conversion of biomass to methane. Final report, June 1, 1976-January 31, 1980

An experimental methane fermentation system was constructed for the purpose of evaluating the processng requirements and conversion efficiencies associated with production of methane from various organic feed stocks. The fermentation reactors had an operating volume 0.775 m/sup 3/. This permitted operation with an approximate continuous feed of milled organics including beef feedlot manure, corn stover, wheat straw and alfalfa hay. A thermochemical pretreatment was applied to the corn stover and wheat straw in order to increase the biodegradability of these substrates. Working with these large units provided sufficient volumes of fermented slurry for evaluation of the dewatering properties of these slurries. Kinetic data were obtained by operating four reactors at different retention times. These data were used to calculate a first order rate constant and the percent of substrate volatile solids that were biodegradable. These data were obtained on beef feed lot manure at 40/sup 0/C and 60/sup 0/C nominal fermentation temperatures. Data from the fermentation of corn stover showed that the biodegradability of the stover volatile solids was only 36 percent at the thermophilic fermentation temperature. The first order rate constant was found to be 0.25 day/sup -1/. Thermochemical pretreatment increased the biodegradability of stover volatile solids to 71 …
Date: February 1, 1980
Creator: Pfeffer, J T
Object Type: Report
System: The UNT Digital Library
XTAL system of crystallographic programs: programmer's manual (open access)

XTAL system of crystallographic programs: programmer's manual

This document establishes the basis for collaborative writing of transportable computer programs for x-ray crystallography. The concepts and general-purpose utility subroutines described here can be readily adapted to other scientific calculations. The complete system of crystallographic programs and subroutines is called XTAL and replaces the XRAY (6,7,8) system of programs. The coding language for the XTAL system is RATMAC (5). The XTAL system of programs contains routines for controlling execution of application programs. In this sense it forms a suboperating system that presents the same computational environment to the user and programmer irrespective of the operating system in use at a particular installation. These control routines replace all FORTRAN I/O code, supply character reading and writing, supply binary file reading and writing, serve as a support library for applications programs, and provide for interprogram communication.
Date: February 1, 1980
Creator: Hall, S. R.; Stewart, J. M.; Norden, A. P.; Munn, R. J. & Freer, S. T.
Object Type: Report
System: The UNT Digital Library
Acoustic agglomeration of power-plant fly ash. A comprehensive semi-annual progress report (open access)

Acoustic agglomeration of power-plant fly ash. A comprehensive semi-annual progress report

Results obtained during the reporting period are presented. The agglomeration of submicron fly ash particles has been studied as a function of sound pressure level, sound frequency, loading, and exposure time. A second generation model of the agglomeration process is being developed. A high-frequency, high-intensity variable speed siren delivering at least 600 W at frequencies up to 4000 Hz has been developed and tested. Details on the design and operation are presented. The agglomeration chamber has been completely cleaned and the aerosol generating system has been rebuilt. A mathematical model of the acoustics of agglomeration is being developed. Preliminary results of computerized electron microscopic scanning of fly ash particles during agglomeration are presented. (DMC)
Date: February 1, 1980
Creator: Reethof, G.
Object Type: Report
System: The UNT Digital Library
Photovoltaic mechanisms in polycrystalline thin-film silicon solar cells (open access)

Photovoltaic mechanisms in polycrystalline thin-film silicon solar cells

Fundamental limitations on the performance of Si solar cells are shown to be quite different from those that have been conventionally invoked. Particularly for heavy-doping effects, the usual models are shown to be invalid and a new method is devised for calculating the reverse saturation current of a heavily doped device in which nearly all minority carriers reach the junction (viz., good blue-response). Calculations by the new method show: (1) increased doping above 10/sup 18/cm/sup -3/ does not improve the open-circuit voltage as has been thought, and (2) previous estimates of bandgap varrowing in diffused cells are much too high because of the neglect of Auger recombination effects. Also of importance are the effects of doping gradients and their relation to the properties of the front surface of a diffused-junction cell; experiments are clarifying some of these relations. These experiments have led to a new, simple method of separating the internal optoelectronic properties of a solar cell (or optical detector) from the reflectance properties of the front surface. This method thus provides a direct means of evaluating the effectiveness of antireflection coatings on such devices.
Date: February 1, 1980
Creator: Redfield, D.
Object Type: Report
System: The UNT Digital Library