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Chemical Processing Department Monthly Report
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3
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Fiscal Year 2007
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Irradiation Processing Department Monthly Record Report
2
A Novel Membrane Reactor for Direct Hydrogen Production From Coal Progress Report
1
A Real-Time Coal Content/Ore Grade (C2OG) Sensor, Technical Report
1
BEETIT Program
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Carbon Sequestration on Surface Mine Lands Quarterly Report
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Heavy ion inertial fusion: interface between target gain, accelerator phase space and reactor beam transport revisited
Recently revised estimates of target gain have added additional optimistic inputs to the interface between targets, accelerators and fusion chamber beam transport. But it remains valid that neutralization of the beams in the fusion chamber is useful if ion charge state Z > 1 or if > 1 kA per beamlet is to be propagated. Some engineering and economic considerations favor higher currents.
Date:
February 22, 1984
Creator:
Barletta, W. A.; Fawley, W. M.; Judd, D. L.; Mark, J. W. K. & Yu, S. S.
Object Type:
Article
System:
The UNT Digital Library
Plasma production and flow in ion beams
Space charge neutralization of ion beams results from plasma generated by the beam. The two dimensional flow of plasma to walls surrounding a beam is analyzed to provide spatial distributions. Negative ion beams receive particular attention; the results are applied to electron control in beams subject to post-acceleration.
Date:
August 22, 1977
Creator:
Hooper, Jr. E. B. & Willmann, P. A.
Object Type:
Report
System:
The UNT Digital Library
Sector 30 collimator radiation
The collimators at Sector 30 of the SLAC accelerator are designed to scrape off a significant fraction (e.g., {approximately}20%) of the SLC beam. The electromagnetic cascade shower that develops in the collimator, and in the scraper and waveguide downbeam, leads to very high radiation exposures of TV cameras (and other devices) located nearby. The collimator (point) source accounts for one-third of the dose and is best shielded by extending the radius of the copper scraper. Radiation from the waveguide accounts for the remaining two-thirds of the dose, and is difficult to shield since it is a line source. However, the spectrum from the waveguide is expected to be softer than that from the collimator. This paper discusses shielding of these sources.
Date:
February 22, 1990
Creator:
Namito, Y. (Ship Research Inst., Tokyo (Japan)); Nelson, W. R. & Benson, E.
Object Type:
Report
System:
The UNT Digital Library
Some considerations for geothermal district heating
The distribution of geothermal resources in relation to the location of population centers in the U.S. is considered. Capital aspects of district heating systems are discussed. Estimates are given of distribution network capital investment as a function of population in service area. Swedish and Icelandic cost experience is taken into consideration. The need for more specific assessment of the potential for direct use of geothermal energy is cited. (JGB)
Date:
June 22, 1977
Creator:
Karkheck, J.
Object Type:
Article
System:
The UNT Digital Library
Dissolution processes. [224 references]
This review contains more than 100 observations and 224 references on the dissolution phenomenon. The dissolution processes are grouped into three categories: methods of aqueous attack, fusion methods, and miscellaneous observations on phenomena related to dissolution problems. (DLC)
Date:
October 22, 1976
Creator:
Silver, G. L.
Object Type:
Report
System:
The UNT Digital Library
Separation of B/sub 4/C powder by air classification
Large quantities of bulk powder can be separated according to particle size and density by air classifiers. Classifiers disperse the powder and usually achieve size differentiation by drag and centrifugal forces acting on individual particles in the gas stream. A Donaldson ''acucut'' Classifier for the separation of B/sub 4/C powder is evaluated. Experimental tests were conducted to determine the particle cut sizes and powder yields obtained by variation of operating parameters. To assess the classifier's performance further results of the sharpness of the powder cuts were evaluated and compared with the vendor's prediction. 7 figures, 3 tables.
Date:
December 22, 1976
Creator:
Farrell, C. L. & Biermann, A. H.
Object Type:
Report
System:
The UNT Digital Library
Use of the n,p scattering reaction for neutron flux measurements
Several contemporary proton-recoil detectors are described and compared. These detectors have been used for neutron-spectrum measurements over various portions of the 10-keV-to-20-MeV energy range. Several factors which limit the accuracy of the results are compared quantitatively. General suggestions are given for setting and using standard cross sections and for future developments using the n,p scattering reaction.
Date:
March 22, 1977
Creator:
Czirr, J. B.
Object Type:
Article
System:
The UNT Digital Library
Predicting subsidence over coal-gasification sites
The extent to which earth subsidence may be caused by in situ coal gasification is studied using the method of finite elements. This study takes into account rock failure modes and nonlinearity of rock stiffness. Two models were studied for the site at Hoe Creek, where a coal seam is overlain and underlain by interbedded clays and sandstones. These two studies are expected to bracket any subsidence that may occur. Maximum subsidence was 0.06 in. using the stiff model and 3.5 in. using the soft model, neither of which suggests undesirably large subsidence.
Date:
November 22, 1976
Creator:
Langland, R. & Fletcher, D.
Object Type:
Report
System:
The UNT Digital Library
Program for calculating x-ray powder diffraction interplanar (d) spacings with a Tektronix-31 desk top programmable calculator
A Tektronix-31 (Tektronix Inc. Beaverton, Oregon) desk top calculator program, which is used as a backup to the PDP-8/I computer program, is described. The program yields interplanar (d) spacings and (2theta) angle values from measurements made on an x-ray diffraction film of a powdered sample of a crystalline material. Use of the calculator provides accurate computations in a relatively rapid time interval when the PDP-8/I is not functioning because of downtime for repairs, maintenance, etc.
Date:
February 22, 1977
Creator:
Eckstein, R. R. & Ishida, Y. G.
Object Type:
Report
System:
The UNT Digital Library
Beam diagnostics on ARGUS
Performance of laser fusion targets depends critically on the characteristics of the incident beam. The spatial distribution and temporal behavior of the light incident on the target varies significantly with power, with choice of beam spatial profile and with location of spatial filters. On each ARGUS shot we photograph planes in the incident beams which are equivalent to the target plane. Array cameras record the time integrated energy distributions and streak cameras record the temporal behavior. Computer reduction of the photographic data provides detailed spatial energy distributions, and instantaneous power on target vs. time. Target performance correlates with the observed beam characteristics.
Date:
September 22, 1976
Creator:
MacQuigg, D. R. & Speck, D. R.
Object Type:
Article
System:
The UNT Digital Library
Systematics of neutron-induced fisson cross sections over the energy range 0. 1 MeV to 15 MeV and at 0. 0253 eV
Previous studies by Behrens have provided evidence of systematic behavior in neutron-induced fission cross sections in the incident neutron energy range 3 to 5 MeV. Recently measured fission cross-section ratios revealed this behavior. In this report, these measurements and those of others are used to illustrate the behavior of fission cross sections over the neutron energy range 0.1 MeV to 15 MeV. Similar trends are seen at 0.0253 eV, as revealed by thermal cross-section measurements. 12 figures.
Date:
June 22, 1977
Creator:
Behrens, J. W.
Object Type:
Report
System:
The UNT Digital Library
Symmetry and illumination uniformity requirements for high density laser-driven implosions
As laser capabilities increase, implosions will be performed to achieve high densities. Criteria are discussed for formation of a low-density corona, preheated supersonically, which increases the tolerance of high convergence implosions to non-uniform illumination by utilizing thermal smoothing. We compare optimized double shell target designs without and with atmosphere production. Two significant penalties are incurred with atmosphere production using 1 ..mu..m laser light. First, a large initial shock at the ablation surface limits the pulse shaping flexibility, and degrades implosion performance. Second, the mass and heat capacity of the atmosphere reduce the energy delivered to the ablation surface and the driving pressures obtained for a given input energy. Improvement is possible using 2 ..mu..m light for the initial phase of the implosion. We present results of 2-D simulations which evaluate combined symmetry and stability requirements. At l = 8, the improvement produced in the example is a factor of 10, giving tolerance of 10 percent.
Date:
October 22, 1976
Creator:
Mead, W. C. & Lindl, J. D.
Object Type:
Article
System:
The UNT Digital Library
Suitability of Tophet C-Alloy 52/Kovar components to hydrogen environments
The suitability of Tophet C-Alloy 52/Kovar weldments to hydrogen embrittlement were investigated because of their potential as candidate materials in fabrication of minaturized initiators for pyrotechnics. Cathodic charged samples were statically loaded for extended periods of time resulting in no load failures and in ductile fracture surfaces indicating resistance to hydrogen embrittlement. 20 figures.
Date:
June 22, 1976
Creator:
Gebhart, J. M. & Kelly, M. D.
Object Type:
Report
System:
The UNT Digital Library
Computer simulation of recent laser driven implosions of glass microshells
Recent experiments at the LLL 2.0 terawatt laser irradiation facility Argus have been conducted on glass microshells filled with equimolar DT gas. A variety of microshell dimensions and laser pulse widths have been used with the best results producing in excess of 10/sup 8/ fusion reactions. Numerical simulation of selected experiments using the LASNEX computer code confirm the measured performance. Peak DT ion temperatures of about 5 keV and densities of .2 gm/cm/sup 3/ are calculated and are in agreement with that from neutron time-of-flight and alpha particle spectral measurements together with x-ray diagnostics. Laser light absorption is about 20% efficient. General characteristics of ''exploding pusher'' targets will be discussed.
Date:
October 22, 1976
Creator:
Thiessen, A. R. & Larsen, J. T.
Object Type:
Article
System:
The UNT Digital Library
Soil structure interaction calculations: a comparison of methods
Two approaches for calculating soil structure interaction (SSI) are compared: finite element and lumped mass. Results indicate that the calculations with the lumped mass method are generally conservative compared to those obtained by the finite element method. They also suggest that a closer agreement between the two sets of calculations is possible, depending on the use of frequency-dependent soil springs and dashpots in the lumped mass calculations. There is a total lack of suitable guidelines for implementing the lumped mass method of calculating SSI, which leads to the conclusion that the finite element method is generally superior for calculative purposes.
Date:
July 22, 1976
Creator:
Wight, L. & Zaslawsky, M.
Object Type:
Report
System:
The UNT Digital Library
Computation of gas-liquid equilibria in high-saline geothermal fluids
A computer-assisted chemical modeling study of equilibria in flowing brine systems has been undertaken. Equilibria between liquid and volatile components of two-phase fluids have profound effects on such important phenomena as corrosion, scale formation, environmental quality, and the economics of energy extraction. The principal reactions considered are those involving volatiles naturally present in the fluid, including NH/sub 3/, H/sub 2/S and CO/sub 2/. A computer code is described which performs stepwise equilibrium computations at 1/sup 0/C intervals for a unit mass of fluid, between reservoir and reinjection temperatures. The data base used is the quality-temperature function for the brine, the chemical composition, and equilibrium constants for the solubility reactions of gases and dissociation of their aqueous species. Chemical changes that take place during cooling and expansion are illustrated by distribution diagrams. Although the computations were developed for application to the high-saline resource, they are not fluid or system-specific, and should be of general usefulness where a chemical composition and temperature history can be specified.
Date:
April 22, 1977
Creator:
Jackson, D. D.
Object Type:
Article
System:
The UNT Digital Library
Range of investigation of a borehole gravimeter
Concepts of the range of investigation of a borehole gravimeter are reviewed. It is shown that the maximum sensitivity to a mass point at a horizontal distance R from a borehole occurs at a vertical distance Z = R/..sqrt..2. Thus, the angle of maximum sensitivity is about 55/sup 0/ from the vertical. It is also shown that the absolute value of the gravitational effect decreases with increasing R. There are two maxima of the vertical gradient of gravity (at Z = 0 and at Z = ..sqrt../sup 3///sub 2/ R). The minimum distance required between gravimeter stations to obtain a usable measurement can be determined. The slab radius R for which the gravitational effect of a horizontal slab is equal to 45%, 90%, etc., of that of an infinite horizontal slab is a function of the measurement spacing. The closer the measurement spacing, the more information obtained.
Date:
February 22, 1977
Creator:
Hearst, J. R.
Object Type:
Article
System:
The UNT Digital Library
Program plan for the Brayton Isotope Power System. Phase I. Design, fabrication and test of the Brayton Isotope Power System
Phase I of an overall program for the development of a 500 to 2000 W(e) (EOM), 7-y life, power system for space vehicles is discussed. The system uses a closed Brayton dynamic system to convert energy from an isotope heat source at a net efficiency greater than 25 percent. This first phase, a 35-month effort, is for the conceptual design of a 1300 W(e), 450 lb flight system and the design, fabrication, and test of a ground demonstration system. The flight system will use, for the baseline design, two of the multihundred-watt (MHW) heat sources being developed. The Ground Demonstration System will simulate, as closely as possible, the Brayton Isotope Power Flight System and will utilize components and technology being developed for the Mini-Brayton rotating unit, recuperator and heat source assembly, respectively. The Ground Demonstration System includes a performance test and a 1000-h endurance test.
Date:
October 22, 1975
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
High-intensity, subkolovolt x-ray calibration facility using a Cockroft--Walton proton accelerator
Considerable need has arisen for the development of well-calibrated x-ray detectors capable of detecting photons with energies between 100 and 1000 electron-volts. This energy region is of significant interest since the x-ray emission from high-temperature (kT approximately 1.0 keV), laser-produced plasmas is predominantly in this range. A high-intensity, subkilovolt x-ray calibration source was developed which utilizes proton-induced inner-shell atomic fluorescence of low-Z elements. The high photon yields and low bremsstrahlung background associated with this phenomenon are ideally suited to provide an intense, nearly monoenergetic x-ray calibration source for detector development applications. The proton accelerator is a 3 mA, 300 kV Cockroft-Walton using a conventional rf hydrogen ion source. Seven remotely-selectable liquid-cooled targets capable of heat dissipation of 5 kW/cm/sup 2/ are used to provide characteristic x-rays with energies between 100 and 1000 eV. Source strengths are of the order of 10/sup 13/ to 10/sup 14/ photons/sec. A description of the facility is presented. Typical x-ray spectra (B-K, C-K, Ti-L, Fe-L and Cu-L) and flux values will be shown. Problems such as spectral contamination due to carbon buildup on the target and to backscattered particles are discussed.
Date:
October 22, 1976
Creator:
Kuckuck, R. W.; Gaines, J. L. & Ernst, R. D.
Object Type:
Article
System:
The UNT Digital Library
/sup 233/U breeding and neutron multiplying blankets for fusion reactors
In this work, along with a previous paper three possible uses of 14-MeV deuterium--tritium fusion neutrons are investigated: energy production, neutron multiplication, and fissile-fuel breeding. The results presented include neutronic studies of fissioning and nonfissioning thorium systems, tritium breeding systems, various fuel options (UO/sub 2/, UC, UC/sub 2/, etc.), and uranium as well as refractory metal first-wall neutron-multiplying regions. A brief energy balance and an estimate of potential revenues for fusion devices are given to help illustrate the potentials of these designs.
Date:
September 22, 1975
Creator:
Cook, A. G. & Maniscalco, J. A.
Object Type:
Article
System:
The UNT Digital Library
Examination of temperature-induced shape memory of uranium--5. 3-to 6. 9 weight percent niobium alloys
The uranium-niobium alloy system was examined in the range of 5.3-to-6.9 weight percent niobium with respect to shape memory, mechanical properties, metallography, Coefficients of linear thermal expansion, and differential thermal analysis. Shape memory increased with increasing niobium levels in the study range. There were no useful correlations found between shape memory and the other tests. Coefficients of linear thermal expansion tests of as-quenched 5.8 and 6.2 weight percent niobium specimens, but not 5.3 and 6.9 weight percent niobium specimens, had a contraction component on heating, but the phenomenon was not a contributor to shape memory.
Date:
September 22, 1976
Creator:
Hemperly, V. C.
Object Type:
Report
System:
The UNT Digital Library
Computational Quantum Chemistry [Website]
This report contains the contents of a web page related to research on the development of quantum chemistry methods for computational thermochemistry and the application of quantum chemistry methods to problems in material chemistry and chemical sciences. Research programs highlighted include: Gaussian-2 theory; Density functional theory; Molecular sieve materials; Diamond thin-film growth from buckyball precursors; Electronic structure calculations on lithium polymer electrolytes; Long-distance electronic coupling in donor/acceptor molecules; and Computational studies of NOx reactions in radioactive waste storage.
Date:
August 22, 1997
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
LMFBR safety. 2. Review of current issues and bibliography of literature, 1970--1972
This report discusses the current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1970 through 1972. The bibliography consists of approximately 1620 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included for completeness.
Date:
November 22, 1976
Creator:
Buchanan, J. R. & Keilholtz, G. W.
Object Type:
Report
System:
The UNT Digital Library
Radioactive demonstration of DWPF product control strategy
The effectiveness of the product and process control strategies that will be utilized by the Defense Waste Processing Facility (DWPF) was demonstrated during a campaign in the Shielded Cells Facility (SCF) of the Savannah River Technology Center (SRTC). The remotely operated process included the preparation of the melter feed, vitrification in a slurry-fed 1/100th scale melter and analysis of the glass product both for its composition and durability. The campaign processed approximately 10 kg (on a dry basis) of radioactive sludge from Tank 51. This sludge is representative of the first batch of sludge that will be sent to the DWPF for immobilization into borosilicate glass. Additions to the sludge were made based on calculations using the Product Composition Control System (PCCS). Analysis of the glass produced during the campaign showed that a durable glass was produced with a composition similar to that predicted using the PCCS.
Date:
April 22, 1992
Creator:
Andrews, M. K. & Bibler, N. E.
Object Type:
Report
System:
The UNT Digital Library