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.
Object Type: Report
System: The UNT Digital Library
Advanced /sup 90/Sr space power supply. 250 watt dynamic system (open access)

Advanced /sup 90/Sr space power supply. 250 watt dynamic system

None
Date: September 6, 1973
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Compatibility testing of vitrified waste forms (open access)

Compatibility testing of vitrified waste forms

An experimental program to evaluate candidate metals for use in the fabrication of canisters for long-term storage of vitrified radioactive wastes is described. The long-term compatibility of the candidate metal both with the contained vitrified radioactive waste and with the external environments expected in possible final storage locations will be determined. These tests involve heating combinations of waste forms and canister metals in intimate contact for up to 50,000 hr to accelerate any reactions that occur.
Date: March 6, 1978
Creator: Rankin, W.N.
Object Type: Article
System: The UNT Digital Library
Joining of ceramics for high performance energy systems. Mid-term progress report, August 1, 1979-March 31, 1980 (open access)

Joining of ceramics for high performance energy systems. Mid-term progress report, August 1, 1979-March 31, 1980

The subject program is primarily an exploratory and demonstration study of the use of silicate glass-based adhesives for bonding silicon-base refractory ceramics (SiC, Si/sub 3/N/sub 4/). The projected application is 1250 to 2050/sup 0/F relaxing joint service in high-performance energy conversion systems. The five program tasks and their current status are as follows. Task 1 - Long-Term Joint Stability. Time-temperature-transformation studies of candidate glass adhesives, out to 2000 hours simulated service exposure, are half complete. Task 2 - Environmental and Service Effects on Joint Reliability. Start up delayed due to late delivery of candidate glass fillers and ceramic specimens. Task 3 - Viscoelastic Damping of Glass Bonded Ceramics. Promising results obtained over approximately the same range of glass viscosity required for joint relaxation function (10/sup 7.5/ to 10/sup 9.5/ poise). Work is 90% complete. Task 4 - Crack Arrest and Crack Diversion by Joints. No work started due to late arrival of materials. Task 5 - Improved Joining and Fabrication Methods. Significant work has been conducted in the area of refractory pre-glazing and the application and bonding of high-density candidate glass fillers (by both hand-artisan and slip-spray techniques). Work is half complete.
Date: October 6, 1980
Creator: Smeltzer, C E & Metcalfe, A G
Object Type: Report
System: The UNT Digital Library
Operating manual for the de Phanger precision long counter (PLC) (open access)

Operating manual for the de Phanger precision long counter (PLC)

The setting up, calibration operation, characteristics, and problems of the precision long counter for neutron intensity measurements are discussed. (WHK)
Date: February 6, 1978
Creator: Slaughter, D.
Object Type: Report
System: The UNT Digital Library
Kinetics of the radiation-induced exchange reactions of H/sub 2/, D/sub 2/, and T/sub 2/: a review (open access)

Kinetics of the radiation-induced exchange reactions of H/sub 2/, D/sub 2/, and T/sub 2/: a review

Mixtures of H/sub 2/--T/sub 2/ or D/sub 2/--T/sub 2/ will exchange to produce HT or DT due to catalysis by the tritium ..beta.. particle. The kinetics of the reaction D/sub 2/ + T/sub 2/ = 2DT may play an important role in designing liquid or solid targets of D/sub 2/--DT--T/sub 2/ for implosion fusion, and distillation schemes for tritium cleanup systems in fusion reactors. Accordingly, we have critically reviewed the literature for information on the kinetics and mechanism of radiation-induced self-exchange reactions among the hydrogens. We found data for the reaction H/sub 2/ + T/sub 2/ = 2HT in the gas phase and developed a scheme based on these data to predict the halftime to equilibrium for any gaseous H/sub 2/ + T/sub 2/ mixture at ambient temperature with an accuracy of +-10 percent. The overall order of the H/sub 2/ + T/sub 2/ = 2HT reaction is 1.6 based on an initial rate treatment of the data. The most probable mechanism for radiation-induced self-exchange reaction is an ion-molecule chain mechanism.
Date: January 6, 1978
Creator: Pyper, J.W. & Briggs, C.K.
Object Type: Report
System: The UNT Digital Library
Shiva automatic alignment systems: a brief description (open access)

Shiva automatic alignment systems: a brief description

A diagram is given of the basic Shiva alignment system. The alignment requirements, as originally specified and as preseently estimated, together with the performance obtained to date from the prototype equipment are described. It is expected that this performance will be satisfactory for even the most alignment-sensitive targets and significantly better than is needed for experiments not requiring highly uniform illumination. The hardware arrangement planned for a typical Shiva chain is shown.
Date: September 6, 1977
Creator: Bliss, E. S.; Summers, M. A.; Cody, R. L.; Boyd, R. D. & Wintemute, J. D.
Object Type: Report
System: The UNT Digital Library
Optimization of a VISAR for measuring flyer-plate velocities (open access)

Optimization of a VISAR for measuring flyer-plate velocities

VISAR (Velocity Interferometer System for Any Reflector) is commonly used for measuring flyer-plate velocities up to 6 km/s. Flyer plates can travel as much as 1 mm, which is large compared to usual depth-of-focus requirements for VISARs. Flyer plates are explosively driven, or driven by some other very energetic means; as such, they must be tested in a chamber, which will contain the explosion. Routing the laser beam to the chamber and the signal beam to the VISAR can be done safely and easily in multi-mode optical fibers. We have optimized a fiber-coupled VISAR system for measuring flyer-plate velocities. This system given constant signal levels over the full travel of the flyer plate. Furthermore, the signal-collection efficiency is maximized, which allows use of a moderately sized laser. We also have optimized the VISAR cavity so it does not limit the system efficiency while giving a velocity sensitivity of about 1 km/s per fringe. 5 refs.
Date: May 6, 1992
Creator: Sweatt, W. C.; Crump, O. B., Jr. & Brigham, W. P.
Object Type: Article
System: The UNT Digital Library
Processes of energy deposition by heavy particle impact. Technical report No. 2 (open access)

Processes of energy deposition by heavy particle impact. Technical report No. 2

Experimental studies of the Li/sup +/ + He interaction have been extended to smaller internuclear separations to clarify a discrepancy between experiment and theory in the elastic cross sections and to observe and measure cross sections for inelastic excitation. For R less than or equal to 0.5 a/sub 0/ the elastic scattering differential cross section is observed to droop far below that expected from a single-state interaction based on ab initio ground-state potentials. In this same region of R both one- and two-electron excitations of He are observed to be strongly excited, and cross sections were measured for each of them. The lowest inelastic channel is an electron-capture state, which is observed indirectly to be strongly populated also. A diabatic correlation diagram is constructed that exhibits the basic interactions responsible for the excitation.
Date: July 6, 1971
Creator: Lorents, D. C. & Conklin, G. M.
Object Type: Report
System: The UNT Digital Library
Foreign and domestic discussions on natural geothermal power and potential use of Plowshare to stimulate these natural systems (open access)

Foreign and domestic discussions on natural geothermal power and potential use of Plowshare to stimulate these natural systems

None
Date: July 6, 1971
Creator: Burnham, J. B. & Stewart, D. H.
Object Type: Report
System: The UNT Digital Library
Introduction to magnetic confinement fusion diagnostics (open access)

Introduction to magnetic confinement fusion diagnostics

These notes present a brief survey of some of the current diagnostic techniques used in magnetic fusion plasma devices. To give an idea of the range of parameters and geometries encountered the parameters of four representative experiments - PLT, TMX, ZT-40 and EBT-I(S) - are given. The central issue of all experiments is to understand the flow of power which can be summarized by two volume integrated equations for the ions and electrons.
Date: June 6, 1980
Creator: Turner, W.C.
Object Type: Report
System: The UNT Digital Library
Advanced /sup 90/Sr space power supply. 250 watt static system (open access)

Advanced /sup 90/Sr space power supply. 250 watt static system

None
Date: September 6, 1973
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Heat exchanger method: ingot casting; fixed abrasive method: multi-wire slicing (Phase II). Silicon sheet growth development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project. Quarterly progress report No. 1, November 21, 1977--December 31, 1977 (open access)

Heat exchanger method: ingot casting; fixed abrasive method: multi-wire slicing (Phase II). Silicon sheet growth development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project. Quarterly progress report No. 1, November 21, 1977--December 31, 1977

A high degree of crystallinity has been achieved in ingots cast. Since most of the growth took place near the solidification temperature, the top portion of the ingot was solidified by freezing from the surface. The thickness of this layer was reduced with the control of thermal flow characteristics in the furnace. The crucibles used in this study have a nonuniform bottom which is not conducive to proper heat transfer during solidification. In an effort to achieve high packing density of solar cells in the module with maximum material utilization, an attempt was made to cast a square cross-section ingot. Even though some minor cracking occurred in the first ingot, it appears feasible to cast square cross-section ingots by the Heat Exchanger Method. Higher feed forces results in higher cutting rates. However, this is accompanied by wire wander and increased surface damage depth. It has been established that the life of an impregnated blade can be prolonged by plating it after impregnation.
Date: January 6, 1978
Creator: Schmid, F. & Khattak, C.P.
Object Type: Report
System: The UNT Digital Library
Determination of trace impurities in uranium hexafluoride by an inductively coupled argon plasma spectrometer (open access)

Determination of trace impurities in uranium hexafluoride by an inductively coupled argon plasma spectrometer

A procedure has been developed to determine 21 trace impurity elements in uranium hexafluoride, using inductively coupled argon plasma emission spectrometry (ICAP). The method consists of a liquid-liquid extraction to separate uranium from the trace impurities with a mixture of tri-(2-ethyl-hexyl)-phosphate (TEHP) and heptane. The raffinate containing the elements is subsequently analyzed by ICAP. The impurity elements which can be analyzed by this method are: Al, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Na, Ni, Pb, Sb, Sn, Ti, V and Zn.
Date: January 6, 1983
Creator: Short, B. W.; Spring, H. S. & Grant, R. L.
Object Type: Report
System: The UNT Digital Library
Public opinion and nuclear power decision-making (open access)

Public opinion and nuclear power decision-making

This document discusses public opinion regarding nuclear power which is particularly difficult to tie down because of five important paradoxes that characterize it: it can be based on sound reason, but also on intense emotion; it is both national and local in perspective; at varying times it has seen nuclear power as both clean'' and dirty''; it believes nuclear power is both economic, and uneconomic; and nuclear power is perceived as having a fairly safe record, but being potentially unsafe. Equally as complex as the process by which public opinion is formed is the process by which it is converted into public policy. The American political system has numerous checks and balances designed to moderate the power of public opinion. A complex series of legislative, judicial, and executive branch hurdles must be cleared before any idea, however popular, can become day-to-day operating reality in government. As a result, major changes in policy or programs are difficult, and we may expect that nuclear power will be no different; radical change in one direction or the other is unlikely. Nevertheless, carefully focused programs could achieve modest progress, and carefully designed public opinion surveys could support such programs.
Date: August 6, 1991
Creator: Benson, B.
Object Type: Report
System: The UNT Digital Library
Thulium-170 heat source (open access)

Thulium-170 heat source

An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.
Date: September 6, 1990
Creator: Walter, Carl E.; Van Konynenburg, Richard & VanSant, James H.
Object Type: Report
System: The UNT Digital Library
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 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.
Object Type: Report
System: The UNT Digital Library
LOFT Steam Generator thermal analysis Class I review (open access)

LOFT Steam Generator thermal analysis Class I review

A Class 1 review of the thermal analysis of the LOFT Steam Generator and of the transient thermal analysis of LOFT steam generator thermal well was made to confirm compliance of the analyses with the LOFT Technical Specifications, with the LOFT integral test system - preliminary component design description for the steam generator, and with Appendix C of ANC Specification 60139. Included in this review is an examination of the thermal transients and conditions to insure adequate conservatism in analyzed conditions and transients to which the LOFT Steam Generator (including thermal well) might be exposed while in service at the LOFT reactor facility. Also, a review of the thermal code used was made to check for its applicability to these analyses.
Date: October 6, 1977
Creator: Kinnaman, T.L.
Object Type: Report
System: The UNT Digital Library
Beryllium usage in fusion blankets and beryllium data needs. [None] (open access)

Beryllium usage in fusion blankets and beryllium data needs. [None]

Increasing numbers of designers are choosing beryllium for fusion reactor blankets because it, among all nonfissile materials, produces the highest number (2.5 neutron in an infinite media) of neutrons per 14-MeV incident neutron. In amounts of about 20 cm of equivalent solid density, it can be used to produce fissile material, to breed all the tritium consumed in ITER from outboard blankets only, and in designs to produce Co-60. The problem is that predictions of neutron multiplication in beryllium are off by some 10 to 20% and appear to be on the high side, which means that better multiplication measurements and numerical methods are needed. The n,2n reactions result in two helium atoms, which cause radiation damage in the form of hardening at low temperatures (<300/degree/C) and swelling at high temperatures (>300/degree/C). The usual way beryllium parts are made is by hot pressing the powder. A lower cost method is to cold press and then sinter. There is no radiation damage data on this form of beryllium. The issues of corrosion, safety relative to the release of the tritium built-up inside beryllium, and recycle of used beryllium are also discussed. 10 figs.
Date: April 6, 1988
Creator: Moir, Ralph W.
Object Type: Article
System: The UNT Digital Library
High-temperature borate liquids: physical properties of glass-forming compositions (open access)

High-temperature borate liquids: physical properties of glass-forming compositions

Several experimental routes can be used to develop a better understanding of the polymeric constitution (polyanionic and/or polyhedral distribution) of borate, germanate, and silicate glasses. Spectral, chemical, physical-chemical, and mechanical property information can be determined directly for the glass compositions of interest. Generally, only physical-chemical information is readily accessible for the corresponding high temperature liquids. It will be shown that information on each state of matter has its own particular merits. Most of the evidence thus far published suggests an excellent agreement between polyhedral distributions in an oxide glass and its corresponding high temperature liquid state. There is no well known oxide glass forming system for which such a state of affairs does not exist. In spite of this, occasional efforts are put forth which ignore some of what is known for oxide liquids, glasses, and crystals. Such attempts therefore invariably imply, if only indirectly, that significant changes occur in the polyhedral distributions close to the glass transition temperature region. Specific examples to be discussed will include efforts that avoid well known coordination change equilibria such as BO/sub 3/ reversible BO/sub 4/ and GeO/sub 4/ reversible GeO/sub 6/.
Date: May 6, 1977
Creator: Riebling, E.F.
Object Type: Article
System: The UNT Digital Library
Experimental development of nuclear pumped laser candidate for inertial confinement fusion driver (open access)

Experimental development of nuclear pumped laser candidate for inertial confinement fusion driver

A report is given on progress made during the second year of a three year contract studying the feasibility of nuclear pumping the atomic iodine laser. Experimental results are presented showing efficiencies of 25--38% at converting neutron-induced nuclear reaction energy in the excimer XeBr into UV photons which can be used to pump the laser. Parametric studies were done utilizing the {sup 10}B(n,{alpha}){sup 7}Li reaction, with three bromine donor chemicals, over a range of pressures and mix ratios, to optimize the fluorescence efficiency.
Date: June 6, 1990
Creator: Miley, George H.
Object Type: Report
System: The UNT Digital Library
Innovative Clean Coal Technology (ICCT): Demonstration of innovative applications of technology for cost reductions to the CT-121 FGD process (open access)

Innovative Clean Coal Technology (ICCT): Demonstration of innovative applications of technology for cost reductions to the CT-121 FGD process

The objective of this project is to demonstrate on a commercial scale several innovative applications of cost-reducing technology to the Chiyoda Thoroughbred-121 (CT-121) process. CT-121 is a second generation flue gas desulfurization (FGD) process which is considered by the Electric Power Research Institute (EPRI) and Southern Company Services (SCS) to be one of the most reliable and lowest cost FGD options for high-sulfur coal-fired utility boiler applications. Demonstrations of the innovative design approaches will further reduce the cost and provide a clear advantage to CT121 relative to competing technology.
Date: August 6, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
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.
Object Type: Report
System: The UNT Digital Library
Glass-heat-pipe evacuated-tube solar collector (open access)

Glass-heat-pipe evacuated-tube solar collector

A glass heat pipe is adapted for use as a solar energy absorber in an evacuated tube solar collector and for transferring the absorbed solar energy to a working fluid medium or heat sink for storage or practical use. A capillary wick is formed of granular glass particles fused together by heat on the inside surface of the heat pipe with a water glass binder solution to enhance capillary drive distribution of the thermal transfer fluid in the heat pipe throughout the entire inside surface of the evaporator portion of the heat pipe. Selective coatings are used on the heat pipe surface to maximize solar absorption and minimize energy radiation, and the glass wick can alternatively be fabricated with granular particles of black glass or obsidian.
Date: August 6, 1981
Creator: McConnell, R.D. & VanSant, J.H.
Object Type: Patent
System: The UNT Digital Library