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The development of precipitated iron catalysts with improved stability (open access)

The development of precipitated iron catalysts with improved stability

The objective of this program is to identify the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and to use these chemical principles in the design of catalysts suitable for slurry reactors. The performance targets are 88% CO+H{sub 2} conversion with less than 1% deactivation/day for 1 month and a methane and ethane selectivity of no more than 7% (based on hydrocarbons and oxygenates only) at a space velocity of at least 2 normal liters per hr per gram iron (NL/hr/gFe) using a synthesis gas with 0.5-1.0 H{sub 2}:CO ratio in a slurry reactor.
Date: May 6, 1992
Creator: Abrevaya, H.
System: The UNT Digital Library
Aerial radiometric and magnetic survey, San Angelo National Topographic Map: Texas, West Texas Project. Final report (open access)

Aerial radiometric and magnetic survey, San Angelo National Topographic Map: Texas, West Texas Project. Final report

The results of analyses of the airborne gamma radiation and total magnetic field survey flown for the region identified as the San Angelo National Topographic Map NH14-1 are presented. The airborne data gathered are reduced by ground computer facilities to yield profile plots of the basic uranium, thorium, and potassium equivalent gamma radiation intensities, ratios of these intensities, aircraft altitude above the earth's surface, total gamma ray and earth's magnetic field intensity, correlated as a function of geologic units. The distribution of data within each geologic unit, for all surveyed map lines and tie lines, has been calculated and is included. Two sets of profiled data for each line are included, with one set displaying the above-cited data. The second set includes only flight line magnetic field, temperature, pressure, altitude data plus magnetic field data as measured at a base station. A general description of the area, including descriptions of the various geologic units and the corresponding airborne data, is included.
Date: May 1, 1980
Creator: unknown
System: The UNT Digital Library
An update on passive correctors for the SSC dipole magnets (open access)

An update on passive correctors for the SSC dipole magnets

The concept of correction of the magnetization sextupole became a topic of discussion as soon as it was realized that superconductor magnetization could have a serious effect on the SSC beam during injection. Several methods of correction were proposed. These included (1) correction with active bore tube windings like those on the HERA machine which correct out magnetization sextupole and the sextupole due to iron saturation, (2) correction with persistent sextupole windings mounted on the bore tube (3) correction using passive superconductor (4) correction using ferromagnetic material, and (5) correction using oriented magnetized materials. This report deals with the use of passive superconductor to correct the magnetization sextupole. Two basic methods are explored in this report: (1) One can correct the magnetization sextupole by changing the diameter of the superconductor filaments in one or more blocks of the SSC dipole. (2) One can correct the magnetization sextupole and decapole by mounting passive superconducting wires on the inside of the SSC dipole coil bore. In addition, an assessment of the contribution of each conductor in the dipole to the magnetization sextupole and decapole is shown. 38 refs, 25 figs., 15 tabs.
Date: May 1, 1991
Creator: Green, Michael A.
System: The UNT Digital Library
Organic Nuclear Reactors: An Evaluation of Current Development Programs (open access)

Organic Nuclear Reactors: An Evaluation of Current Development Programs

Organic reactor technology is critically evaluated and areas of research and development work now lacking or inadequate for the successful development of this reactor concept are indicated. The development programs for present organic and heavy water moderated concepts appear generally adequate to reach specific goals. However, the narrow scope of the organic reactor program should be broadened to assure coverage of areas where the application of novel principles might result in marked economic benefits. Further work, principally of a basic nature, is recommended in the fields of chemistry, processing, management, and thermodynamic properties of coolants, in fuel development, and in concept evaluation. (N.W.R.)
Date: May 1, 1961
Creator: unknown
System: The UNT Digital Library
Gas-cooled fast breeder reactor. Quarterly progress report, February 1-April 30, 1980 (open access)

Gas-cooled fast breeder reactor. Quarterly progress report, February 1-April 30, 1980

Information is presented concerning the reactor vessel; reactivity control mechanisms and instrumentation; reactor internals; primary coolant circuits;core auxiliary cooling system; reactor core; systems engineering; and reactor safety and reliability;
Date: May 1980
Creator: unknown
System: The UNT Digital Library
The Electrical Resistivity of Molten and Solid Thorium-Magnesium Eutetic (open access)

The Electrical Resistivity of Molten and Solid Thorium-Magnesium Eutetic

Electrical resistivity properties of polycrystalline 39 wt % thorium-- magnesium eutectic are reported for the solid from room temperature to its melting point at 589 deg C and as a liquid from its melting point to 900 deg C. The electrical resistivity of the eutectic at the melting point was 69.5 microhm- centimeters; it decreased to a value of 64.8 microhm-centimeters at 900 C. Tantalum tubing was used to contain the alloy in the molten state. (auth)
Date: May 1, 1962
Creator: Provow, D. M. & Fisher, R. W.
System: The UNT Digital Library
A Program of FRC Theory Research Annual Report (open access)

A Program of FRC Theory Research Annual Report

At the request of the Office of Fusion Energy, a group of experts was convened on February 6--8, 1990. This group met to assess the world data base on Reversed Field Pinch (RFP) physics, and, further, to assess the role of the ZTH experiment in providing reactor relevant physics understanding for that confinement geometry. This group met, analyzed some of the relevant literature, and heard extensive presentations on the physics of the RFP and the plans for the ZTH and RFX devices. The conclusions of this group of experts are contained in this report.
Date: May 18, 1990
Creator: Krall, Nicholas A.
System: The UNT Digital Library
Site Specific Verification Guidelines. (open access)

Site Specific Verification Guidelines.

The Bonneville Power Administration (BPA) and the Northwest region have moved from energy surplus to a time when demand for energy is likely to exceed available supplies. The Northwest Power Planning Council is calling for a major push to acquire new resources.'' To meet anticipated loads in the next decade, BPA and the region must more than double that rate at which we acquire conservation resources. BPA hopes to achieve some of this doubling by programs independently designed and implemented by utilities and other parties without intensive BPA involvement. BPA will accept proposals for programs using performance-based payments, in which BPA bases its reimbursement to the sponsor on measured energy savings rather than program costs. To receive payment for conservation projects developed under performance-based programs, utilities and other project developers must propose verification plans to measure the amount of energy savings. BPA has traditionally used analysis of billing histories, before and after measure installation, adjusted by a comparison group on non-participating customers to measure conservation savings. This approach does not work well for all conversation projects. For large or unusual facilities the comparison group approach is not reliable due to the absence of enough comparable non-participants to allow appropriate statistical …
Date: May 1, 1992
Creator: Harding, Steve; Gordon, Frederick M. & Kennedy, Mike
System: The UNT Digital Library
Repair Welding of Fusion Reactor Components (open access)

Repair Welding of Fusion Reactor Components

Recent experimental investigations indicate that the repair welding of irradiated materials containing greater than 1 to 2.5 appm helium leads to catastrophic cracking in the heat affected zone of the weld. The high temperatures and cooling tensile stresses which occur during the welding process lead to enhanced helium bubble growth in the heat affected zone region, resulting in catastrophic cracking upon cooling. An investigation is proposed which seeks to determine the effect of stress state on the helium bubble growth process and develop engineering modifications to the welding process based upon this understanding in an attempt to alleviate or eliminate the weld cracking problem in type 316 stainless steel materials.
Date: May 20, 1992
Creator: Chin, Bryan A.
System: The UNT Digital Library
Design and Feasibility Study of a Pebble Bed Reactor-Steam Power Plant (open access)

Design and Feasibility Study of a Pebble Bed Reactor-Steam Power Plant

The status of development studies being conducted on a pebble bed power reactor is outlined. The items discussed are fuel element manufacture, stability, and reprocessing, and component development. (D.L.C.)
Date: May 1, 1958
Creator: unknown
System: The UNT Digital Library
Investigation of joining techniques for advanced austenitic alloys (open access)

Investigation of joining techniques for advanced austenitic alloys

Modified Alloys 316 and 800H, designed for high temperature service, have been developed at Oak Ridge National Laboratory. Assessment of the weldability of the advanced austenitic alloys has been conducted at the University of Tennessee. Four aspects of weldability of the advanced austenitic alloys were included in the investigation.
Date: May 1, 1991
Creator: Lundin, C. D.; Qiao, C. Y. P.; Kikuchi, Y.; Shi, C. & Gill, T. P. S.
System: The UNT Digital Library
Fundamental theory of elastic wave scattering by defects in elastic materials: integral equation methods for application to ultrasonic flaw detection (open access)

Fundamental theory of elastic wave scattering by defects in elastic materials: integral equation methods for application to ultrasonic flaw detection

The use of ultrasonic methods in nondestructive testing depends on the interpretation of the scattering of sound waves by flaws. The theory of elastic waves and their scattering in non-uniform media is developed in detail from first principles, and in generality. Both integral equation and differential methods are discussed, with emphasis on the former. General methods for defining scattering cross sections are presented, and conservation theorems are noted. The Born Approximation to the integral equation is presented, and computed results for several experimental situations are discussed. Several corrections to papers in the literature are made, and in particular the exact scattering of a transverse wave by a spherical flaw is compared with the Rayleigh (long wave) limit.
Date: May 1, 1976
Creator: Gubernatis, J.E.; Domany, E.; Krumhansl, J.A. & Huberman, M.
System: The UNT Digital Library
Results of the 1988 Geothermal Gradient Test Drilling Project for the State of Washington (open access)

Results of the 1988 Geothermal Gradient Test Drilling Project for the State of Washington

During late summer and early fall of 1988, the Washington Department of Natural Resources, Division of Geology and Earth Resources (DGER) completed drilling eight shallow geothermal gradient test wells in the southern Washington Cascade Range. This report describes the preliminary results of the 1988 drilling and gradient measuring, and summarizes our current perspectives on distribution and magnitude of the geothermal resource potential in the southern Washington Cascades. 18 refs., 11 figs., 11 tabs.
Date: May 1989
Creator: Barnett, D. B. & Korosec, M. A.
System: The UNT Digital Library
Investigation of induced unimolecular decomposition for development of visible chemical lasers. Final report, 1 May 1976--30 April 1977 (open access)

Investigation of induced unimolecular decomposition for development of visible chemical lasers. Final report, 1 May 1976--30 April 1977

This report summarizes the results of a study of azide decomposition for possible application in a visible chemical laser. Task 1 of the subject contract involved thorough review of the chemical literature pertaining to azide decomposition. Covalently bonded azides decompose directly into an electronically excited nitrene (RN) and ground-state molecular nitrogen. Ionic azides decompose to metal atoms and azide radicals. The azide radicals subsequently recombine to form electronically excited nitrogen molecules. Task 2, the experimental phase of this program, involved the study of azide-radical reactions. A flow reactor was built in which large concentrations (up to 10/sup 13/ molec cm/sup -3/) of N/sub 3/ could be produced from the thermal decomposition of NaN/sub 3/. The kinetics of and chemiluminescent products from several reactions of N/sub 3/ have been studied, and a method for obtaining absolute concentrations of N/sub 3/ is described. The potential utility of azide decomposition for the production of excited electronic states suitable for a laser device and further areas of research germane to this goal are discussed briefly.
Date: May 1, 1977
Creator: Piper, L G & Taylor, R L
System: The UNT Digital Library
Study of impurities in the Tandem Mirror Experiment using extreme-ultraviolet spectroscopy (open access)

Study of impurities in the Tandem Mirror Experiment using extreme-ultraviolet spectroscopy

Impurities in the Tandem Mirror Experiment (TMX) have been studied using extreme ultraviolet spectroscopy. Three time-resolving absolutely-calibrated normal-incidence monochromators, one on each section of TMX, were used to study the impurity emissions in the wavelength range of 300 A to 1600 A. The instruments on the east end cell and central cell were each capable of obtaining spatially-resolved profiles from 22 chords of the plasma simultaneously while the instrument on the west end cell monitored the central chord. The impurities identified in TMX were carbon, nitrogen, oxygen, and titanium. Emphasis was placed upon determining the impurity densities and radiated power losses of the central cell; results indicate that the impurity concentrations were low - less than 0.4% for each species - and that less than 10% of the total net trapped neutral beam power was lost to radiation. The use of titanium gettering on the central cell walls was observed to decrease the brightnesses of singly- and doubly-ionized carbon and oxygen in the central cell plasma. In the end cells, oxygen was the main impurity with a concentration of about 1.5% and was injected by the neutral beams; the other impurities had concentrations of about 0.5%. Radiation losses from the …
Date: May 12, 1982
Creator: Strand, O. T.
System: The UNT Digital Library
A THEORETICAL STUDY OF SIMPLE MANY-ELECTRON SYSTEMS (open access)

A THEORETICAL STUDY OF SIMPLE MANY-ELECTRON SYSTEMS

None
Date: May 1, 1961
Creator: Sachs, L.M.
System: The UNT Digital Library
Use of ICRH for startup and initial heating of the TMX-U central cell (open access)

Use of ICRH for startup and initial heating of the TMX-U central cell

Ion cyclotron resonance heating (ICRH) was evaluated and it was found to be satisfactory for use in establishing the conditions necessary to form a thermal barrier in TMX-upgrade (TMX-U). We discuss the constraints that must be satisfied in order to maintain a plasma, and outline a complete startup scenario that ends with the plasma at design parameters. The detailed discussions in this report concentrate on those parts of startup where ICRH is necessary. The ability of ICRH to couple power into a plasma at the fundamental ion cyclotron resonance, w/sub ci/, is determined from experiments with a half-turn loop antenna in the Phaedrus tandem mirror central cell. From these experiments, we get the empirical scaling that shows power deposited in the plasma is proportional to the plasma density.
Date: May 1, 1982
Creator: Molvik, A.W. & Falabella, S.
System: The UNT Digital Library
Background radiation from fission pulses (open access)

Background radiation from fission pulses

Extensive source terms for beta, gamma, and neutrons following fission pulses are presented in various tabular and graphical forms. Neutron results from a wide range of fissioning nuclides (42) are examined and detailed information is provided for four fuels: /sup 235/U, /sup 238/U, /sup 232/Th, and /sup 239/Pu; these bracket the range of the delayed spectra. Results at several cooling (decay) times are presented. For ..beta../sup -/ and ..gamma.. spectra, only /sup 235/U and /sup 239/Pu results are given; fission-product data are currently inadequate for other fuels. The data base consists of all known measured data for individual fission products extensively supplemented with nuclear model results. The process is evolutionary, and therefore, the current base is summarized in sufficient detail for users to judge its quality. Comparisons with recent delayed neutron experiments and total ..beta../sup -/ and ..gamma.. decay energies are included. 27 refs., 47 figs., 9 tabs.
Date: May 1, 1988
Creator: England, T. R.; Arthur, E. D.; Brady, M. C. & LaBauve, R. J.
System: The UNT Digital Library
Solar Pilot Plant, Phase I. Preliminary design report. Volume II. System description and system analysis. CDRL item 2 (open access)

Solar Pilot Plant, Phase I. Preliminary design report. Volume II. System description and system analysis. CDRL item 2

Honeywell conducted a parametric analysis of the 10-MW(e) solar pilot plant requirements and expected performance and established an optimum system design. The main analytical simulation tools were the optical (ray trace) and the dynamic simulation models. These are described in detail in Books 2 and 3 of this volume under separate cover. In making design decisions, available performance and cost data were used to provide a design reflecting the overall requirements and economics of a commercial-scale plant. This volume contains a description of this analysis/design process and resultant system/subsystem design and performance.
Date: May 1, 1977
Creator: unknown
System: The UNT Digital Library
Milliwatt Generator Project (open access)

Milliwatt Generator Project

This report covers progress on the Milliwatt Generator Project from April 1986 through March 1988. Activities included fuel processing and characterization, production of heat sources, fabrication of pressure-burst test units, compatibility studies, impact testing, and examination of surveillance units. The major task of the Los Alamos Milliwatt Generator Project is to fabricate MC2893A heat sources (4.0 W) for MC2730A radioisotope thermoelectric generators (RTGS) and MC3599 heat sources (4.5 W) for MC3500 RTGs. The MWG Project interfaces with the following contractors: Sandia National Laboratories, Albuquerque (designer); E.I. du Pont de Nemours and Co. (Inc.), Savannah River Plant (fuel); Monsanto Research Corporation, Mound Facility (metal hardware); and General Electric Company, Neutron Devices Department (RTGs). In addition to MWG fabrication activities, Los Alamos is involved in (1) fabrication of pressure-burst test units, (2) compatibility testing and evaluation, (3) examination of surveillance units, and (4) impact testing and subsequent examination of compatibility and surveillance units.
Date: May 1, 1992
Creator: Latimer, T.W. & Rinehart, G.H.
System: The UNT Digital Library
Radio-frequency size effect and the Fermi surface of aluminum (open access)

Radio-frequency size effect and the Fermi surface of aluminum

None
Date: May 1, 1975
Creator: Hartman, J.S.
System: The UNT Digital Library
Design of a continuous duty cryopump (open access)

Design of a continuous duty cryopump

A continuous duty cryopump system was designed and developed that comprises a self-contained cryopump for installation into a vacuum chamber, and a microprocessor controller for automatic operation. This deuterium pump has two units in a single housing, arranged so that one is pumping while the other is being regenerated. Liquid helium-cooled, finned sections in each unit pump deuterium by condensation, and a third pump integral within the cryopump housing collects the regenerated gas. A microprocessor unit controls distribution of liquid and gaseous helium, used for conditioning the pumping units, and operates remote actuators for the regeneration. Software provides fully automatic, timed sequencing of the repetitive cryopump events which include: cooldown of the pumping units, opening of the louvers isolating the unit from the vacuum chamber, closing of the louvers, and warming up of the unit for regeneration. Default values in the software can be reprogrammed by the operator through the keyboard in response to prompts displayed on the computer. An override allows the operator to control the cryopump manually by activating switches on a control panel. Interlocks to prevent cryogen lockup are included in the software.
Date: May 1, 1985
Creator: Sedgley, D.W.
System: The UNT Digital Library
Locations and areas of ponds and Carolina Bays at the Savannah River Plant (open access)

Locations and areas of ponds and Carolina Bays at the Savannah River Plant

The Savannah River Plant has 28 ponds and 190 Carolina Bays on its 192,000-acreite. Excluding the Par Pond system, the mean pond area is 17.6 acre, with a range of 0.4 to 202.8 acres. Par Pond is the largest pond, with an area of 2500 acres. The mean Carolina Bay area is 6.6 acres, with a range of less than 0.3 to 124.0 acres. The geographical location of each pond and bay has been digitized and can be graphically displayed by computer. This capability will facilitate identification of wetland areas as required by Executive Order 11990 (Protection of Wetlands, May 24, 1977).
Date: May 1, 1982
Creator: Shields, J. D.; Woody, N. D.; Dicks, A. S.; Hollod, G. J.; Schalles, J. & Leversee, G. J.
System: The UNT Digital Library
Cumulative impacts study of The Geysers KGRA: public-service impacts of geothermal development (open access)

Cumulative impacts study of The Geysers KGRA: public-service impacts of geothermal development

Geothermal development in The Geysers KGRA has affected local public services and fiscal resources in Sonoma, Lake, Mendocino, and Napa counties. Each of these counties underwent rapid population growth between 1970 and 1980, some of which can be attributed to geothermal development. The number of workers currently involved in the various aspects of geothermal development in The Geysers is identified. Using three different development scenarios, projections are made for the number of power plants needed to reach the electrical generation capacity of the steam resource in The Geysers. The report also projects the cumulative number of workers needed to develop the steam field and to construct, operate, and maintain these power plants. Although the number of construction workers fluctuates, most are not likely to become new, permanent residents of the KGRA counties. The administrative and public service costs of geothermal development to local jurisdictions are examined and compared to geothermal revenues accruing to the local governments. Revenues do not cover the immediate fiscal needs resulting from increases in local road maintenance and school enrollment attributable to geothermal development. Several mitigation options are discussed, and a framework is presented for calculating mitigation costs per unit of public service.
Date: May 1, 1982
Creator: Matthews, K.M.
System: The UNT Digital Library