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Is the two-term expansion valid for highly anisotropic systems. The Townsend ionization coefficient in strong runaway as a test case (open access)

Is the two-term expansion valid for highly anisotropic systems. The Townsend ionization coefficient in strong runaway as a test case

The Townsend ionization coefficient in the strong runaway regime is calculated within the framework of the two-term expansion. Results are compared to the 1-D model. General features of the two models are qualitatively similar, but quantitative differences by factors of approx. 2 are observed.
Date: July 15, 1982
Creator: Yu, S. S. & Melendez, R. E.
System: The UNT Digital Library
Introduction to nuclear test engineering (open access)

Introduction to nuclear test engineering

The basic information in this report is from a vu-graph presentation prepared to acquaint new or prospective employees with the Nuclear Test Engineering Division (NTED). Additional information has been added here to enhance a reader's understanding when reviewing the material after hearing the presentation, or in lieu of attending a presentation.
Date: July 15, 1982
Creator: O'Neal, W.C. & Paquette, D.L.
System: The UNT Digital Library
RMDF leach-field decontamination. Final report (open access)

RMDF leach-field decontamination. Final report

The objective of the decontamination effort was to place the Radioactive Materials Disposal Facility (RMDF) leach field in a condition suitable for release for unrestricted use. Radioactively contaminated soil was excavated from the leach field to produce a condition of contamination as low as reasonably achievable (ALARA). The contaminated soil was boxed and shipped to an NRC-licensed burial site at Beatty, Nevada, and to the DOE burial site at Hanford, Washington. The soil excavation project successfully reduced the contamination level in the leach field to background levels, except for less than 0.6 mCi of Sr-90 and trace amounts of Cs-137 that are isolated in cracks in the bedrock. The cracks are greater than 10 ft below the surface and have been sealed with a bituminous asphalt mastic. A pathways analysis for radiation exposure to humans from the remaining radionuclides was performed, assuming intensive home gardening, and the results show that the total first year whole body dose equivalent would be about 0.1 mrem/year. This dose equivalent is a projection for the hypothetical ingestion of vegetables grown on the site. Assuming that an average adult consumes 64 kg of green leafy vegetables per year and that the entire yearly supply could …
Date: September 15, 1982
Creator: Carroll, J W; Marzec, J M & Stelle, A M
System: The UNT Digital Library
Mechanisms affecting mass transfer in fuel cells (open access)

Mechanisms affecting mass transfer in fuel cells

An initial analysis of particulate effects on molten carbonate fuel cells has been conducted. The analysis has been applied to a conceptual fuel cell with operating parameters appropriate to use with future power generation plants. Particle transport due to several mechanisms has been considered and dominant mechanisms affecting particle delivery to anode channel surfaces and into anode pores have been identified. Thermophoresis and gas flow out from anode pores have been found to inhibit particle arrival on the anode and entry into pores so that neither anode channel blockage nor pore blockage are expected for particles with diameters smaller than about one micron. The analytical approach developed could be applied to other fuel cell types in addition to the molten carbonate fuel cells.
Date: March 15, 1982
Creator: Wenglarz, R.A.
System: The UNT Digital Library
Development of model reference adaptive control theory for electric power plant control applications (open access)

Development of model reference adaptive control theory for electric power plant control applications

The scope of this effort includes the theoretical development of a multi-input, multi-output (MIMO) Model Reference Control (MRC) algorithm, (i.e., model following control law), Model Reference Adaptive Control (MRAC) algorithm and the formulation of a nonlinear model of a typical electric power plant. Previous single-input, single-output MRAC algorithm designs have been generalized to MIMO MRAC designs using the MIMO MRC algorithm. This MRC algorithm, which has been developed using Command Generator Tracker methodologies, represents the steady state behavior (in the adaptive sense) of the MRAC algorithm. The MRC algorithm is a fundamental component in the MRAC design and stability analysis. An enhanced MRC algorithm, which has been developed for systems with more controls than regulated outputs, alleviates the MRC stability constraint of stable plant transmission zeroes. The nonlinear power plant model is based on the Cromby model with the addition of a governor valve management algorithm, turbine dynamics and turbine interactions with extraction flows. An application of the MRC algorithm to a linearization of this model demonstrates its applicability to power plant systems. In particular, the generated power changes at 7% per minute while throttle pressure and temperature, reheat temperature and drum level are held constant with a reasonable level …
Date: September 15, 1982
Creator: Mabius, L.E.
System: The UNT Digital Library
Development program to support industrial coal gasification. Quarterly report 1 (open access)

Development program to support industrial coal gasification. Quarterly report 1

The Development Program to Support Industrial Coal Gasification is on schedule. The efforts have centered on collecting background information and data, planning, and getting the experimental program underway. The three principal objectives in Task I-A were accomplished. The technical literature was reviewed, the coals and binders to be employed were selected, and tests and testing equipment to be used in evaluating agglomerates were developed. The entire Erie Mining facility design was reviewed and a large portion of the fluidized-bed coal gasification plant design was completed. Much of the work in Task I will be experimental. Wafer-briquette and roll-briquette screening tests will be performed. In Task II, work on the fluidized-bed gasification plant design will be completed and work on a plant design involving entrained-flow gasifiers will be initiated.
Date: January 15, 1982
Creator: unknown
System: The UNT Digital Library
Assessment of deposition for power-plant molten-carbonate fuel cells (open access)

Assessment of deposition for power-plant molten-carbonate fuel cells

Particulate deposition in molten carbonate fuel cell anodes is addressed for operation with future coal gasification power plants. Power plant systems factors affecting deposition are explored such as gas cleanup requirements for particulate removal and gasifier product gas composition differences for various gasifier types and operational modes (air blown versus oxygen blown). Effects of fuel cell characteristics (including average cell current density and fuel utilization) on anode deposition are also quantified. Particulate effects on molten carbonate fuel cell anode performance may not be as detrimental as perhaps perceived in the past. Gas cleanup to remove virtually all particles larger than one micron in diameter is expected to prevent or at least greatly reduce anode deposition. However, cathode deposition in molten carbonate fuel cells should be evaluated in the future since cathodes are likely more prone to deposition than anodes even though cathode channel particle concentrations are much lower.
Date: March 15, 1982
Creator: Wenglarz, R. A.
System: The UNT Digital Library
Wisconsin collector-efficiency study, phase two (open access)

Wisconsin collector-efficiency study, phase two

The collector efficiency study developed a solar collector rating methodology specific to Wisconsin conditions. Existing rating programs were researched and a collector methodology was developed. A computer program was written to calculate the collector ratings and 25 collector models were rated. The accuracy of the proposed rating methodology was evaluated for 16 collectors placed in 11 domestic hot water systems. One liquid space heating analysis with storage and one air space heating analysis without storage were completed. A solar assisted heat pump in which the solar collectors function as evaporators was also analyzed.
Date: January 15, 1982
Creator: Abright, B.L.
System: The UNT Digital Library
Synthetic fuel aromaticity and staged combustion (open access)

Synthetic fuel aromaticity and staged combustion

Samples of middle and heavy SRC-II distillates were distilled into 50 C boiling point range fractions. These were characterized by measurements of their molecular weight, elemental analysis and basic nitrogen content and calculation of average molecular structures. The structures typically consisted of 1 to 3 aromatic rings fused to alicyclic rings with short, 1 to 3 carbon aliphatic side chains. The lower boiling fractions contained significant amounts (1 atom/molecule) of oxygen while the heavier fractions contained so few heteroatoms that they were essentially hydrocarbons. Laboratory scale oxidative-pyrolysis experiments were carried out at pyrolysis temperatures of 500 to 1100 C and oxygen concentrations from 0 to 100 percent of stoichiometry. Analysis of liquid products, collected in condensers cooled with liquid nitrogen showed that aromatization is a major reaction in the absence of oxygen. The oxygen-containing materials (phenolics) seem to be more resistant to thermal pyrolysis than unsubstituted aromatics. Nitrogen converts from basic to nonbasic forms at about 500 C. The nonbasic nitrogen is more stable and survives up to 700 C after which it is slowly removed. A recently constructed 50,000 Btu/hr staged combustor was used to study the chemistry of the nitrogen and aromatics. SRC II combustion was studied under …
Date: November 15, 1982
Creator: Longanbach, J. R.; Chan, L. K. & Levy, A.
System: The UNT Digital Library
Health and safety evaluation of a modified tunnel-borer design for application to single-entry coal-mine development (open access)

Health and safety evaluation of a modified tunnel-borer design for application to single-entry coal-mine development

The health and safety analysis is part of an overall effort to identify and develop innovative underground coal extraction systems. The single-entry tunnel borer system was initially considered an innovative approach to underground mining because it exhibited a means of increasing the speed and efficiency of entry development by reducing the number of entries. However, to be considered a truly advanced system, the tunnel borer had to meet distinct safety criteria as well. The objective was to examine the tunnel borer design and determine whether it offset major health hazards, and satisfied the prescribed safety levels. As a baseline for comparison, the tunnel borer was compared against the continuous mining entry driving system. The results of the health analysis indicated that while the tunnel borer design offered improvements in dust control through the use of water sprays, a higher face ventilation rate, and the application of spalling rather than the conventional grinding process, it interjected an additional mutagenic is and toxic compound into the environment through the use of shotcrete. The tunnel borer system easily conformed with the prescribed fatality limit, but exceeded the required limits for disabling and overall injuries. It also exhibited projected disabling and overall injury rates …
Date: February 15, 1982
Creator: Zimmerman, W. F.
System: The UNT Digital Library
Lasers in chemical processing (open access)

Lasers in chemical processing

The high cost of laser energy is the crucial issue in any potential laser-processing application. It is expensive relative to other forms of energy and to most bulk chemicals. We show those factors that have previously frustrated attempts to find commercially viable laser-induced processes for the production of materials. Having identified the general criteria to be satisfied by an economically successful laser process and shown how these imply the laser-system requirements, we present a status report on the uranium laser isotope separation (LIS) program at the Lawrence Livermore National Laboratory (LLNL).
Date: April 15, 1982
Creator: Davis, J.I.
System: The UNT Digital Library
Annual technical report: fiscal year 1981 (open access)

Annual technical report: fiscal year 1981

The activities of the JPL Solar Thermal Power Systems Parabolic Dish Project are summarized for FY 1981. Included are discussions on subsystem designs of concentrators, receivers, engines, power converters, and thermal transport. Analyses and test results are also included along with progress on field tests, Small Community System development and the Parabolic Dish Test Site.
Date: March 15, 1982
Creator: unknown
System: The UNT Digital Library
Theory and tests of two-phase turbines (open access)

Theory and tests of two-phase turbines

Two-phase turbines open the possibility of new types of power cycles operating with extremely wet mixtures of steam and water, organic fluids, or immiscible liquids and gases. Possible applications are geothermal power, waste-heat recovery, refrigerant expansion, solar conversion, transportation turbine engines, and engine bottoming cycles. A theoretical model for two-phase impulse turbines was developed. Apparatus was constructed for testing one- and two-stage turbines (using speed decrease from stage to stage). Turbines were tested with water-and-nitrogen mixtures and Refrigerant 22. Nozzle efficiencies were 0.78 (measured) and 0.72 (theoretical) for water-and-nitrogen mixtures at a water/nitrogen mixture ratio of 68, by mass; and 0.89 (measured) and 0.84 (theoretical) for Refrigerant 22 expanding from 0.02 quality to 0.28 quality. Blade efficiencies (shaft power before windage and bearing loss divided by nozzle jet power) were 0.63 (measured) and 0.71 (theoretical) for water-and-nitrogen mixtures and 0.62 (measured) and 0.63 (theoretical) for Refrigerant 22 with a single-stage turbine, and 0.70 (measured) and 0.85 (theoretical) for water-and-nitrogen mixtures with a two-stage turbine.
Date: March 15, 1982
Creator: Elliot, D.G.
System: The UNT Digital Library
BNL Neutral-Beam Development Group. Progress report FY 1981 (open access)

BNL Neutral-Beam Development Group. Progress report FY 1981

The Brookhaven High Energy Neutral Beam Development Group is developing injector systems, particularly for the next generation of fusion mirror and tokamak experiments. These injectors are based on the acceleration and neutralization of negative deuterium ions, to utilize their high neutralization efficiency which is nearly independent of energy above 50 keV/nucleon.
Date: January 15, 1982
Creator: Prelec, K. & Sluyters, T.
System: The UNT Digital Library
Evaluation of ADAM/1 model for advanced coal-extraction concepts (open access)

Evaluation of ADAM/1 model for advanced coal-extraction concepts

The Advanced Coal Extraction Project is sponsored by the Department of Energy at the Jet Propulsion Laboratory to define and develop advanced underground coal extraction systems which: (1) are suitable for significant remaining resources after the year 2000, and (2) promise a significant improvement in production cost and miner safety, with no degradation in miner health, environmental quality and resource recovery. System requirements in the five performance areas have been defined by Goldsmith and Lavin (1980). Several existing computer programs for estimating life-cycle cost of mining systems have been evaluated. A commercially available program ADAM/1 was found to be satisfactory in relation to the needs of the Advanced Coal Extraction Project. Two test cases were run to confirm the ability of the program to handle non-conventional mining equipment and procedures. The results were satisfactory. The model, therefore, is recommended to the project team for evaluation of their conceptual designs. Since the model is commercially available, data preparation instructions are not reproduced in this document; instead the reader is referred to the original documents for this information.
Date: January 15, 1982
Creator: Deshpande, G. K. & Gangal, M. D.
System: The UNT Digital Library
Mitigation of biofouling using coatings, year 2. Quarterly progress report No. 2. [PWR; BWR] (open access)

Mitigation of biofouling using coatings, year 2. Quarterly progress report No. 2. [PWR; BWR]

Objectives of this project are to evaluate benefits associated with control of the surface energetic properties of materials used in heat exchangers; and to identify preferred ranges of these surface conditions that minimize deposits of biological fouling known to deteriorate heat exchange efficiencies in cooling water systems. The technical approach employed uses special diagnostic plates in novel flow cells where fluid flow conditions can be well-controlled, modifying the surface chemistry and surface energy of the plates with very thin coatings and examining the earliest events of biofouling caused by macromolecules and microbial organisms. For the present phase of the project (Year 2), attention is focussed on biofouling in a freshwater/brackish water system.
Date: March 15, 1982
Creator: Meyer, A. E.
System: The UNT Digital Library
Relative radiation sensitivity of insulators, stabilizers, and superconductors (open access)

Relative radiation sensitivity of insulators, stabilizers, and superconductors

The objective of this work was to compare the radiation sensitivity of the various parts of superconducting magnet systems. Using the radiation spectra calculated by Engholm for the Engineering Test Facility (ETF) toroidal field magnet inboard leg and available data on radiation effects, commonly used magnet components were ranked in order of radiation sensitivity. It was found that epoxy-based insulators and copper and aluminum stabilizers were the most sensitive parts of the magnets, more sensitive than the superconductors. Use of polyimide-based insulators would make the insulators less vulnerable than the stabilizers and superconductors. An experiment is planned to study the effects of various degrees of cold work on the radiation-induced magnetoresistance of copper, since this will be an important factor for fusion magnet stabilizers.
Date: January 15, 1982
Creator: Van Konynenburg, R.A. & Guinan, M.W.
System: The UNT Digital Library
Evaluation of the Beijing Instrument Factory GDB-44F photomultipler (open access)

Evaluation of the Beijing Instrument Factory GDB-44F photomultipler

Characteristics have been measured for the GDB-44F 2''-diameter photomultiplier. Some typical photomultiplier characteristics - such as gain, dark current, anode output current, transit and rise times as a function of voltage between anode and cathode, and photoelectron pulse-height spectrum, the quantum-efficiency and the single-electron transit time spread were measured. Descriptions of the measuring systems were also given.
Date: December 15, 1982
Creator: Young, E. & Lo, C.C.
System: The UNT Digital Library
Air-quality-model update (open access)

Air-quality-model update

The Livermore Regional Air Quality Model (LIRAQ) has been updated and improved. This report describes the changes that have been made in chemistry, species treatment, and boundary conditions. The results of smog chamber simulations that were used to verify the chemistry as well as simulations of the entire air quality model for two prototype days in the Bay Area are reported. The results for the prototype day simulations are preliminary due to the need for improvement in meteorology fields, but they show the dependence and sensitivity of high hour ozone to changes in selected boundary and initial conditions.
Date: January 15, 1982
Creator: Penner, J.E. & Walton, J.J.
System: The UNT Digital Library
Energy Saver A-Sector Power Test Results (open access)

Energy Saver A-Sector Power Test Results

The superconducting magnets and associated cryogenic components in A-sector represent the initial phase of installation of the Fermilab superconducting accelerator, designed to accelerate proton beams to energies of 1 TeV. Installation of the magnets, comprising one-eighth of the ring, was completed in December, 1981. Cooldown and power tests took place in the first half of 1982, concurrent with main ring use for 400 GeV high energy physics. The tests described in this paper involved 151 cryogenic components in the tunnel: 94 dipoles, 24 quadrupoles, 25 spool pieces, 3 feed cans, 4 turn-around boxes and 1 bypass. Refrigeration was supplied by three satellite refrigerators, the Central Helium Liquefier, and two compressor buildings. The magnets were powered by a single power supply.
Date: September 15, 1982
Creator: Martin, P.; Flora, R.; Tool, G. & Wolff, D.
System: The UNT Digital Library
Energy spectrum of neutrals formed in an ion accelerator (open access)

Energy spectrum of neutrals formed in an ion accelerator

This work presents an estimate of the energy distribution of the neutrals formed in the ion beam accelerator. However it does not determine the fraction of those neutrals which leave the neutral beam injector and go on into the reactor. To do that, more details of the beam line performance are needed.
Date: March 15, 1982
Creator: Fink, J.H.
System: The UNT Digital Library
Physics and numerics of the tensor code (incomplete preliminary documentation) (open access)

Physics and numerics of the tensor code (incomplete preliminary documentation)

The present TENSOR code is a descendant of a code originally conceived by Maenchen and Sack and later adapted by Cherry. Originally, the code was a two-dimensional Lagrangian explicit finite difference code which solved the equations of continuum mechanics. Since then, implicit and arbitrary Lagrange-Euler (ALE) algorithms have been added. The code has been used principally to solve problems involving the propagation of stress waves through earth materials, and considerable development of rock and soil constitutive relations has been done. The code has been applied extensively to the containment of underground nuclear tests, nuclear and high explosive surface and subsurface cratering, and energy and resource recovery. TENSOR is supported by a substantial array of ancillary routines. The initial conditions are set up by a generator code TENGEN. ZON is a multipurpose code which can be used for zoning, rezoning, overlaying, and linking from other codes. Linking from some codes is facilitated by another code RADTEN. TENPLT is a fixed time graphics code which provides a wide variety of plotting options and output devices, and which is capable of producing computer movies by postprocessing problem dumps. Time history graphics are provided by the TIMPLT code from temporal dumps produced during production …
Date: July 15, 1982
Creator: Burton, D.E.; Lettis, L.A. Jr.; Bryan, J.B. & Frary, N.R.
System: The UNT Digital Library
Scanning-Electron-Microscopy Study of Corrosion and Surface Features in Glass Microballoons (open access)

Scanning-Electron-Microscopy Study of Corrosion and Surface Features in Glass Microballoons

Gaseous acid treatment (HBr) of surface-hardened binary glass microballoons results in etching and the growth of salt nodules, tubes or whiskers, depending on moisture conditions. Temperatures from 400/sup 0/C to 625/sup 0/C for 24 h or more are required for the effects to be significant. Numerous imperfections, including craters, are documented on the unexposed interiors surfaces. The evident phase separation and nucleation sites suggest a need for better production controls and post-production annealing. 6 figures.
Date: September 15, 1982
Creator: Bystroff, R. I.
System: The UNT Digital Library
Theoretical studies of chemisorption on transition-metal surfaces: interaction of hydrogen with titanium. Final report, June 1, 1977-August 31, 1982 (open access)

Theoretical studies of chemisorption on transition-metal surfaces: interaction of hydrogen with titanium. Final report, June 1, 1977-August 31, 1982

The research concerns the theory of chemisorption of molecules on solid surfaces: the development of a general formalism, and specific applications to the hydrogen-titanium system. The objective is to develop a suitable formalism for treating electronic interactions at an ab initio level when both localized and delocalized interactions occur, as in the case of molecular adsorption on a metallic surface. For H/sub 2/ and CO adsorption on titanium, the goal is a determination of the energetics of adsorption and molecular dissociation as a function of surface site. The first phase of the research concerned primarily the formalism and the second the modeling of the titanium surface, preparatory to the chemisorption studies. The final phase of the research has dealt with applications of the chemisorption theory to several systems: H/sub 2/ on Ti(0001), CO on Ti(0001), interstitial H in titanium, H on Cu(100) and H/sub 2/ dissociation on Cu(100). Work on stepped copper surfaces and CO interactions with Ni(100) was also begun. With the exception of the latter two projects now underway, the results of all studies have been published. Brief summaries of the individual projects are included in this report.
Date: October 15, 1982
Creator: Whitten, J.L.
System: The UNT Digital Library