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Winter Fuels Report
4
Petroleum Marketing Monthly
3
Fiscal Year 2007
2
Hindered Diffusion of Asphaltenes at Elevated Temperature and Pressure Progress Report
2
Lignite Fuel Enhancement Progress Report
2
Development of Continuous Solvent Extraction Processes for Coal Derived Carbon Products Quarterly Report
1
Enhancement of Equilibrium Shift in Dehydrogenation Reactions Using a Novel Membrane Reactor Semi-Annual Report
1
Fiscal Year 1999
1
Fiscal Year 2000
1
Fiscal Year 2003
1
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Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties
Several new types of silicon-containing preceramic polymers, i.e., poly(diorganosilacetylene) and poly(diorganosilvinylene) have been synthesized with molecular weights from 10,000 to 120,000. These polymers could be thermally converted to SiC with a moderate to high char yields. Ready solubility and good processability made these types of polymers attractive in their applications to ceramics. The thermal polymerization of diethynyldiphenyl-silane, which was reported in 1968 to afford poly(diphenylsilyldiacetylene) via dehydrogenation, was reinvestigated. Spectroscopic studies showed that the polymer had a structure of polyacetylene type not diacetylene. Diphenyldiethynylgermane and a series of diorganodiethynylsilances were synthesized. These could be polymerized in the presence of MoCl{sub 5} or WCl{sub 6} to afford a soluble, violet material with Mw as high as 108,000. 100 refs., 56 figs., 16 tabs.
Date:
October 7, 1991
Creator:
Pang, Yi.
System:
The UNT Digital Library
Low-cost solar array project. Task I. Silicon material. Investigation of the hydrogenation of SiCl/sub 4/
Reaction kinetic measurements on the hydrochlorination of SiCl/sub 4/ and m.g. silicon metal were last reported as a function of reaction temperature, reactor pressure, H/sub 2//SiCl/sub 4/ ratio and silicon metal particle size distribution, 3 SiCl/sub 4/ + 2 H/sub 2/ + Si reversible 4 SiHCl/sub 3/. The effect of impurities in the m.g. silicon metal on the rate of this reaction has been investigated in this quarter. The m.g. silicon was replaced with high purity, electronic grade silicon metal in the hydrochlorination reaction. With electronic grade Si, the reaction rate was found to be about one order of magnitude slower than those obtained with m.g. silicon metal. These metallic impurities in the m.g. silicon appear to have a catalytic effect. Addition of 5 wt% cuprous chloride to the electronic grade Si mass bed increased the reaction rate to the same level as those obtained with m.g. silicon with 5% CuCl added. The effect of prolonged reaction time on the hydrochlorination reaction was studied. The plan is to run the reaction for long periods of time with the objective of studying the life of the Si mass bed. No significant change in the reaction rate was observed after about 80 …
Date:
October 7, 1980
Creator:
Mui, J. Y. P. & Seyferth, D.
System:
The UNT Digital Library
Some Scoping Experiments for a Space Reactor
Some scoping experiments were performed to evaluate fuel performance in a lithium heat pipe reactor operating at a nominal 1500K heat pipe temperature. Fuel-coolant and fuel-coolant-clad relationships showed that once a failed heat pipe occurs temperatures can rise high enough so that large concentrations of uranium can be transported by the vapor phase. Upon condensation this uranium would be capable of penetrating heat pipes adjacent to the failed pipe. The potential for propagation of failure exists with UO/sub 2/ and a lithium heat pipe. Changing the composition of the metal of the heat pipe would have only a second order effect on the kinetics of the failure mechanism. Uranium carbide and nitride were considered as potential fuels which are nonreactive in a lithium environment. At high temperatures the nitride would be favored because of its better compatibility with potential cladding materials. Compositions of UN with small additions of YN appear to offer very attractive properties for a compact high temperature high power density reactor.
Date:
July 7, 1983
Creator:
Alexander, C. A. & Ogden, J. S.
System:
The UNT Digital Library
An MS-DOS-based program for analyzing plutonium gamma-ray spectra
A plutonium gamma-ray analysis system that operates on MS-DOS-based computers has been developed for the International Atomic Energy Agency (IAEA) to perform in-field analysis of plutonium gamma-ray spectra for plutonium isotopics. The user interacts with the system by means of menus and screens that allow the user to select various applications and to enter information pertinent to a measurement. This information, along with the plutonium weight-percent-abundance results from the data analysis, is stored in dBASE III files. The spectral-data-analysis program, IAEAPU, determines the relative plutonium isotopic abundances from gamma-ray peaks in the 110- to 390-keV region of the spectral data. The program is compact so that it may be used on a portable, battery-operated, laptop, personal computer (PC) that uses a 3-1/2-in. floppy diskette. This is intended to be the final report on this work. We describe in detail the data-analysis methodology, the software, and the operation of the plutonium gamma-ray analysis system. 10 refs., 1 fig., 2 tabs.
Date:
September 7, 1989
Creator:
Ruhter, W. D. & Buckley, W. M.
System:
The UNT Digital Library
Geotomography applied at the Stripa Mine in Sweden
LLNL made ultrahigh-frequency (450-MHz) electromagnetic borehole-to-borehole transmissions in the Stripa Mine near Guldsmedshyttan, Sweden, in April 1979. Transmission loss measurements were made between four sets of 76-mm boreholes 30 m long, located at the end of a drift. Distances between the boreholes varied from 2 to 22 m. More than 25,000 data points were taken. A geotomograph was constructed to show the variation of attenuation between boreholes. The observed spatial variation of electromagnetic attenuation may be related to the expected stress relief created by the mine. Transmission loss measurements were also made between two converging boreholes drilled from the surface to points near the mine. Data taken at 21 MHz show a nearly uniform attenuation within this sampled region. These experiments demonstrate that geotomographic data collection/interpretation provides high-resolution images of the underground environment and can provide useful input to those charged with providing the detailed site characterizations needed for both short- and long-term monitoring of underground nuclear waste repositories.
Date:
April 7, 1980
Creator:
Okada, J.T.; Laine, E.F.; Lytle, R.J. & Daily,W.D.
System:
The UNT Digital Library
PWR Blowdown Heat Transfer Separate-Effects Program. Thermal-Hydraulic Test Facility experimental data report for test 103
Reduced instrument responses are presented for Thermal-Hydraulic Test Facility (THTF) test 103, which is part of the ORNL Pressurized-Water Reactor (PWR) Blowdown Heat Transfer Separate-Effects Program. The objective of the program is to investigate the thermal-hydraulic phenomenon governing the energy transfer and transport processes that occur during a loss-of-coolant accident in a PWR system.
Date:
March 7, 1978
Creator:
Clemons, V. D.; White, M. D.; Moore, P. A. & Hedrick, R. A.
System:
The UNT Digital Library
Atomic and molecular science with synchrotron radiation
This paper discusses the following topics: electron correlation in atoms; atomic innershell excitation and decay mechanisms; timing experiments; x-ray scattering; properties of ionized species; electronic properties of actinide atoms; total photon-interaction cross sections; and molecular physics. 66 refs. (LSP)
Date:
November 7, 1989
Creator:
unknown
System:
The UNT Digital Library
A miniature inexpensive, oxygen sensing element
An exhaustive study was conducted to determine the feasibility of Nernst-type oxygen sensors based on ceramics containing Bi{sub 2}O{sub 3}. The basic sensor design consisted of a ceramic sensing module sealed into a metal tube. The module accommodated an internal heater and thermocouple. Thermal-expansion-matched metals, adhesives, and seals were researched and developed, consistent with sequential firings during sensor assembly. Significant effort was devoted to heater design/testing and to materials' compatibility with Pt electrodes. A systematic approach was taken to develop all sensor components which led to several design modifications. Prototype sensors were constructed and exhaustively tested. It is concluded that development of Nerst-type oxygen sensors based on Bi{sub 2}O{sub 3} will require much further effort and application of specialized technologies. However, during the course of this 3-year program much progress was reported in the literature on amperometric-type oxygen sensors, and a minor effort was devoted here to this type of sensor based on Bi{sub 2}O{sub 3}. These studies were made on Bi{sub 2}O{sub 3}-based ceramic samples in a multilayer-capacitor-type geometry and amperometric-type oxygen sensing was demonstrated at very low temperatures ({approximately} 160{degree}C). A central advantage here is that these types of sensors can be mass-produced very inexpensively ({approximately} 20--50 cents …
Date:
October 7, 1991
Creator:
Arenz, R. W.
System:
The UNT Digital Library
Acceleration using total internal reflection
This report considers the use of a dielectric slab undergoing total internal reflection as an accelerating structure for charged particle beams. We examine the functional dependence of the electromagnetic fields above the surface of the dielectric for polarized incident waves. We present an experimental arrangement for testing the performance of the method, using apparatus under construction for the Grating Acceleration experiment at Brookhaven National Laboratory. 13 refs., 4 figs., 2 tabs.
Date:
June 7, 1991
Creator:
Fernow, R.C.
System:
The UNT Digital Library
Evaluation of macroreticular anion exchange resin - RTA-893-R
The macroreticular anion exchange resin, Amberlite IRA-900-OH, and an experimental resin from Ionac Chemical Company were irradiated by a /sup 60/Co source to doses of 5 x 10/sup 7/ rad and 10/sup 8/ rad. These doses approximate or exceed the dose encountered by the deionizer resins in 100-Area service. The loss in exchange capacity and the volume changes of Amberlite IRA-900 on irradiation were similar to those found previously for Amberlite IRA-400. The Ionac experimental resin, which had a considerably lower initial exchange capacity, likewise was not stable to radiation. It is concluded that Amberlite IRA-900 offers no advantage over Amberlite IRA-400 for 100-Area purification service. Since there is little justification for further evaluation of macroreticular resin for 100-Area use, the present work completes RTA-893-R.
Date:
June 7, 1965
Creator:
Baumann, E. W.
System:
The UNT Digital Library
Specific heat loading in Nd:glass lasers
The specific thermal load parameter, chi, for xenon flashlamp-pumped Nd:glass gain media is written as a function of neodymium concentration, pump pulse duration, and energy extraction efficiency. The currently available data on radiative and nonradiative decay probabilities of several commercial Nd:glasses are used to calculate and graph specific thermal load parameter values. By factoring these results into performance scaling relationships for zig-zag and disk lasers, specific Nd:glasses can be selected for optimized laser performance.
Date:
August 7, 1985
Creator:
Krupke, W. F.
System:
The UNT Digital Library
Clean gasoline reforming with superacid catalysts
Tasks reported on this term include optimization of chlorided Pt- alumina catalysts, testing of the optimum Pt/Cl alumina catalysts, preparation and testing of zirconia superacid catalyst. (VC)
Date:
May 7, 1992
Creator:
Davis, B. H.
System:
The UNT Digital Library
SPE water electrolysis technology development for large scale hydrogen production. Progress report No. 4, June 15, 1976--September 30, 1976
Porous carbon fiber paper was selected as the cathode membrane and electrode assembly support based on over 1200 hr operational evaluation. Three potential anode supports are under test. All three appear technically satisfactory after 500 to 1200 hr operational evaluation on each. Optimization of molds and molding techniques for a foil backed ribbed carbon collector of bipolar design, including ribbed flow fields, manifolds, ports and sealing surfaces, is in process. Over 2800 hr demonstrated at 300/sup 0/F on platinum screened cell. Over 2200 hr demonstrated at 300/sup 0/F on cell with carbon cloth cathode current collector. Forty-eight hours screening tests of 56 different anode catalysts have been completed. A 500-hr life test program of 12 anode catalyst types which showed promise on the screening tests has been started. Attempts to stabilize RuO/sub x/ for use as an anode catalyst are being pursued. Low loaded cathodes on graphite substrates show performance to within 25 MV of baseline. Optimization of substrate thickness and fabrication procedures is continuing. Twenty-five low loaded anodes catalyst/substrate combinations have all shown poor performance stability with time. Continued development of the grafted TFS membrane has shown greatly improved physical characteristics and encouraging performance for samples in the 25 …
Date:
October 7, 1976
Creator:
unknown
System:
The UNT Digital Library
Application of the Argonne Advanced Acceleration Test Facility to development for conventional accelerators
The Argonne Advanced Acceleration Test Facility is designed as a powerful tool to test ideas for very high gradient acceleration schemes based on direct beam excitation of plasmas, metal structures, dielectrics, etc. The characteristic size in these systems is )approximately) 1 cm, corresponding to frequencies )approximately) 10 GHz. The question addressed here is whether the special features of this facility have application as well to the development of components for the more conventional, lower frequency, accelerators now operating or under development. It is suggested that the usefulness of the facility for the development of conventional systems could be enhanced by a provision for longer time delay between driver and witness beam pulses. 9 refs., 2 figs.
Date:
April 7, 1988
Creator:
MacLachlan, J.A.
System:
The UNT Digital Library
LOFT suppression tank spray system piping: heat exchanger BS-H-31 piping modifications
A stress analysis of the piping modification, resulting from relocation of heat exchanger BS-H-31 of the LOFT Blowdown Suppressing Tank Spray System, was performed. The piping, fittings, and supports were found to comply with the criteria of Section III of the ASME Boiler and Pressure Vessel Code, 1974.
Date:
November 7, 1977
Creator:
Blandford, R.K.
System:
The UNT Digital Library
Procedure for matching synfuel users with potential suppliers. Appendix B. Proposed and ongoing synthetic fuel production projects
To assist the Department of Energy, Office of Fuels Conversion (OFC), in implementing the synthetic fuel exemption under the Powerplant and Industrial Fuel Use Act (FUA) of 1978, Resource Consulting Group, Inc. (RCG), has developed a procedure for matching prospective users and producers of synthetic fuel. The matching procedure, which involves a hierarchical screening process, is designed to assist OFC in: locating a supplier for a firm that wishes to obtain a synthetic fuel exemption; determining whether the fuel supplier proposed by a petitioner is technically and economically capable of meeting the petitioner's needs; and assisting the Synthetic Fuels Corporation or a synthetic fuel supplier in evaluating potential markets for synthetic fuel production. A data base is provided in this appendix on proposed and ongoing synthetic fuel production projects to be used in applying the screening procedure. The data base encompasses a total of 212 projects in the seven production technologies.
Date:
August 7, 1981
Creator:
unknown
System:
The UNT Digital Library
High pressure gas metering project
The initial research and development of a system that uses high pressure helium gas to pressurize vessels over a wide range of pressurization rates, vessel volumes, and maximum test pressures are described. A method of controlling the mass flow rate in a test vessel was developed by using the pressure difference across a capillary tube. The mass flow rate is related to the pressurization rate through a real gas equation of state. The resulting mass flow equation is then used in a control algorithm. Plots of two typical pressurization tests run on a manually operated system are included.
Date:
July 7, 1980
Creator:
Tripp, L.R.
System:
The UNT Digital Library
Gaseous phase coal surface modification
In this report, we present an improved, feasible and potentially cost effective method of cleaning and beneficiating ultrafine coal. Increased mechanization of mining methods and the need towards depyritization, and demineralization have led to an increase in the quantity of coal fines generated in recent times. For example, the amount of {minus}100 mesh coal occurring in coal preparation plant feeds now typically varies from 5 to 25% of the total feed. Environmental constraints coupled with the greatly increased cost of coal have made it increasingly important to recover more of these fines. Our method chemically modifies the surface of such coals by a series of gaseous phase treatments employing Friedel-Crafts reactions. By using olefins (ethene, propene and butene) and hydrogen chloride catalyst at elevated temperature, the surface hydrophobicity of coal is enhanced. This increased hydrophobicity is manifest in surface phenomena which reflect conditions at the solid/liquid interphase (zeta potential) and those which reflect conditions at the solid/liquid/gas interphases (contact angle, wettability and floatability).
Date:
May 7, 1992
Creator:
Okoh, J.M.; Pinion, J. & Thiensatit, S.
System:
The UNT Digital Library
Field-reversal experiments in the mirror fusion test facility (MFTF)
Detailed consideration of several aspects of a field-reversal experiment was begun in the Mirror Fusion Test Facility (MFTF): Model calculations have provided some plausible parameters for a field-reversed deuterium plasma in the MFTF, and a buildup calculation indicates that the MFTF neutral-beam system is marginally sufficient to achieve field reversal by neutral injection alone. However, the many uncertainties indicate the need for further research and development on alternate buildup methods. A discussion of experimental objectives is presented and important diagnostics are listed. The range of parameter space accessible with the MFTF magnet design is explored, and we find that with proper aiming of the neutral beams, meaningful experiments can be performed to advance toward these objectives. Finally, it is pointed out that if we achieve enhanced n tau confinement by means of field reversal, then quasi-steady-state operation of MFTF is conceivable.
Date:
December 7, 1977
Creator:
Shearer, J.W. & Condit, W.C.
System:
The UNT Digital Library
Advanced direct coal liquefaction. Quarterly technical progress report No. 1, September-November 1983
Wyoming subbituminous coal was liquefied using three different two-stage process configurations in bench-scale tests. These process configurations differed in the type of fractionated deashing resid being recycled to the individual stages. The objective of these runs was to determine whether, by recycle of specific resid streams to the thermal stage, the second stage catalyst life could be improved without detrimentally affecting distillate yield or hydrogen consumption. The results indicate that the two-stage process configuration consisting of hydrotreating the Light Deashed Resid and direct recycle of heavy Deashed Resid to the thermal stage produced the best results. This process configuration resulted in a distillate yield of 54 wt % (MAF coal basis) and overall coal conversion in the 93 to 95% range, as measured by pyridine-soluble analytical test while operating in a total distillate mode. These results are very encouraging from the lower rank Wyoming subbituminous coal. Among the three two-stage process configurations tested, the particular process configuration of hydrotreating Light Deashed Resid resulted in the least amount of catalyst deactivation. As a part of this research effort, a test procedure for quick evaluation of various resids and catalysts in terms of coke precursors was also developed. This procedure utilizing as-produced …
Date:
February 7, 1984
Creator:
Paranjape, A.S.
System:
The UNT Digital Library
Development of magnetic mirror systems for nuclear testing applications
Several system studies have concluded that the small size and steady state nature of magnetic mirror systems provide attractive features for nuclear-testing applications. The principle shortcoming of mirror systems is their small data base relative to that of tokamaks. This paper summarizes the present data base and describes experiments that could be carried out with small modifications of existing facilities to explore plasma physics issues associated with the production of high neutron fluxes in magnetic mirror configurations. The experiments would demonstrate physics principles important to such future applications of fusion power neutrons as blanket testing, tritium production, fissile fuel production, or decontamination of high-level radioactive nuclear-reactor wastes.
Date:
August 7, 1986
Creator:
Simonen, T. C.; Futch, A. H. & Kaiser, T. B.
System:
The UNT Digital Library
Suppression of transverse beam breakup modes in an induction accelerator by gas focusing
The effect of beam-generated positive ions on the beam-breakup instability in linear electron accelerators is calculated using simple models. The strongly nonlinear dependence of the ion focusing force on radius makes a complete suppression of the mode growth possible, in contrast to solenoidal focusing. The predicted gas pressures for significant stabilization of the mode growth in a machine configuration like ATA is relatively low (10/sup -5/ to 10/sup -4/ torr), even for high-Q modes.
Date:
April 7, 1980
Creator:
Briggs, R. J.
System:
The UNT Digital Library
An MS-DOS-based program for analyzing plutonium gamma-ray spectra
A plutonium gamma-ray analysis system that operates on MS-DOS-based computers has been developed for the International Atomic Energy Agency (IAEA) to perform in-field analysis of plutonium gamma-ray spectra for plutonium isotopics. The program titled IAEAPU consists of three separate applications: a data-transfer application for transferring spectral data from a CICERO multichannel analyzer to a binary data file, a data-analysis application to analyze plutonium gamma-ray spectra, for plutonium isotopic ratios and weight percents of total plutonium, and a data-quality assurance application to check spectral data for proper data-acquisition setup and performance. Volume 3 contains the software listings for these applications.
Date:
September 7, 1989
Creator:
Ruhter, W. D. & Buckley, W. M.
System:
The UNT Digital Library
Design and development of Stirling engines for stationary power generation applications in the 500 to 3000 horsepower range. First quarterly report
This project is Phase I of a multi-phased program for the design and development of Stirling engines for stationary power generation applications in the 500 to 3000 horsepower range. Phase I comprises the conceptual design and associated cost estimates of a stationary Stirling engine capable of being fueled by a variety of heat sources, with emphasis on coal firing, followed by the preparation of a plan for implementing the design, fabrication and testing of a demonstration engine by 1985. The main effort in Phase I is the generation of state-of-the-art conceptual designs having greatest potential for prototype testing in 1985. The conceptual designs include a heat transport system for integrating the engine heater head with such energy sources as conventional oil/gas combustors, fluidized bed and other coal combustors, and combustors using coal-derived liquid fuels, and low/medium BTU gases. The heat transport systems being investigated include forced convection with gases or liquids, heat pipes, and direct firing. Currently, the leading choice for the solid fuel combustion system is the atmospheric fluidized bed, with low BTU gasification still a viable alternative. Both systems will continue to be evaluated further, but with greater emphasis on FBC. To date, there appears no clear choice …
Date:
January 7, 1980
Creator:
unknown
System:
The UNT Digital Library