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Radiological survey of the inactive uranium-mill tailings at Falls City, Texas

Description: Results of a radiological survey conducted at the Falls City, Texas, site in July 1976 are presented. There are seven partial to fully stabilized tailings piles, and an overburden pile from an open-pit mine. Above ground gamma-ray exposure rate measurements show moderate levels of contamination throughout the area with a maximum exposure rate of 500 ..mu..R/hr above tailings pile 2. The average exposure rate over the different areas varied from 14 ..mu..R/hr over the southwest end of tailings pile 7 to 207 ..mu..R/hr over the northeast end of the same pile. Analyses of surface soil and dry-wash sediment samples, as well as calculations of subsurface /sup 226/Ra distribution, serve to define the spread of tailings around the area. Water erosion of the tailings is evident, but, because of abundant growth of vegetation on the tailings piles, wind erosion probably is not a major problem.
Date: October 1, 1980
Creator: Haywood, F. F.; Christian, D. J.; Loy, E. T.; Lorenzo, D. & Ellis, B. S.
Partner: UNT Libraries Government Documents Department
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Biliary Excretion of /Sup 99m/Tc Albumin Microaggregate Degradation Products (a Method for Measuring Kupffer Cell Digestive Function.).

Description: The rapid metabolism of radioactive albumin colloids used for liver-spleen-bone marrow scanning radiation exposure to these organs and permits one to study the proteolytic digestive capacity of the reticuloendothial system (RES)
Date: October 31, 1971
Creator: Kitani, K. & Taplin, G. V.
Partner: UNT Libraries Government Documents Department
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A unified theory of resonant excitation of kinetic ballooning modes by energetic ions/alpha particles in tokamaks

Description: A complete theory of wave-particle interactions is presented whereby both circulating and trapped energetic ions can destabilize kinetic ballooning modes in tokamaks. Four qualitatively different types of resonances, involving wave-precessional drift, wave-transit, wave-bounce, and precessional drift-bounce interactions, are identified, and the destabilization potential of each is assessed. For a characteristic slowing-down distribution function, the dominant interaction is that which taps those resonant ions with the highest energy. Implications of the theory for present and future generation fusion experiments are discussed. 16 refs.
Date: October 1, 1991
Creator: Biglari, H. & Chen, L.
Partner: UNT Libraries Government Documents Department
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Accidental Radiogold (198Au) Liver Scan Overdose With Fatal Outcome

Description: This report addresses the use of radioisotopes for scanning, which has added significantly to the clinician's ability to detect and interpret disease manifestations.
Date: October 31, 1969
Creator: Baron, J.M.; Yachnin, S.; Polcyn, R.; Fitch, F.W. & Sturner, W.G.
Partner: UNT Libraries Government Documents Department
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Recording Equipment for Internal Friction Measurements

Description: An apparatus was developed for recording internal friction data in such a manner as to circumvent many of the laborious and time-consuming observations and calculations usually associated with these measurements. An optical lever is used and the passage of the beam across the scale is detected by photoconductive cells. The cells are strategically located so that, when their signals are fed through a multichannel switching circuit to the pens of an operation recorder, a plot of the logarithm of the vibrational amplitude versus the number of cycles is recorded on the chart. From the definitmon of the logarithmic decrement, ( delta ), it can be shown that the slope of this curve is - delta . The apparatus is inexpensive and requires a minimum of maintenance. It has been used for accurate determinations of values of delta from below 0.0001 up to 0.3. (auth)
Date: October 31, 1961
Creator: Stephenson, R. L. & McCoy, H. E. Jr.
Partner: UNT Libraries Government Documents Department
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Intermediate-depth geothermal temperature study. Gradient holes: 11-33 and 63-33, Soda Lake, NV

Description: During 1979, Chevron Resources Company drilled two 2000 ft holes near Soda Lake in the Nevada Carson Sink area to obtain subsurface data for inclusion in the US Department of Energy's Northern Basin and Range geothermal reservoir assessment program. Drilling information together with detailed lithologic, geophysical and temperature log data were compiled for each hole and is summarized in this report. Maximum stabilized temperatures of 297/sup 0/F and 367/sup 0/F were encountered at total depth in each of the holes, respectively.
Date: October 1, 1979
Creator: Hill, D.G.
Partner: UNT Libraries Government Documents Department
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Establishment of viscometer capability for geopressured fluids. Project 61024 final report, November 19, 1978-December 31, 1979

Description: The feasibility of modifying the IGT capillary viscometer for the measurement of methane-saturated brines at 10,000 psi and 200/sup 0/C was evaluated. The viscometer was cleaned, modified, reassembled and pressure treated. The density cells were calibrated to a precision of approximately 7%. The viscosity of pure value was measured and the best value obtained was 6% below values reported in the literature. The operation of the viscometer was time-consuming and required meticulous cleaning between experiments. Some corrosion at the mercury surface interfered with the efficient operation of the timing device. Other problems were encountered due to gas bubbles trapped in the capillary flow path. Consequently, data on methane-saturated brine could not be obtained within the funding limitations of this program. It is concluded that further work on the existing viscometer would not be cost-effective.
Date: October 1, 1980
Creator: Rockar, E. & Randolph, P.
Partner: UNT Libraries Government Documents Department
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ORR Operations for Period April 1961 to April 1962

Description: A summary of the activities in the 4th operational year is presented for the ORR. On-stream time at 30 Mw was relatively steady with 75.4 and 83.7% representing the lowest and highest quarters. Modification of the ball-latch mechanism of the shim-rod-drives is in progress. The primary cooling system bypass control valve was modified and a d-c pony motor was added at the No. 3 primary pump. This addition was made to increase the reliability of adequate water flow for afterheat cooling. A study of coreboiling detection is being conducted. (J.R.D.)
Date: October 16, 1962
Creator: Binford, F.T.; Casto, W.R. & Colomb, A.L.
Partner: UNT Libraries Government Documents Department
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Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

Final Report of Modeling of CWM Droplet Combustion

Description: The objective of the present study was to develop a one-dimensional, unsteady state model for coal-water mixture droplet combustion, and to compare the characteristic times for the various processes, such as water vaporization, devolatilization and char oxidation with available experimental data. A water film surrounding a spherical coal particle is considered to undergo vaporization by heat transfer from the hot air. After the water vaporization is complete, devolatilization begins. This process is assumed to be kinetically controlled. Water vaporization and devolatilization processes are modeled by using a hybrid Eulerian-Lagrangian method to obtain the properties of the gas-phase and the condensed-phase. An explicit finite difference scheme is used to solve the Eulerian gas-phase equation where as a Runga-Kutta scheme is employed to solve the Lagrangian condensed-phase equations. The predicted characteristic times for water vaporization is in good agreement with values proposed in the literature. At the present time there is insufficient data to draw any conclusions on the model. Methods are proposed to refine the simple kinetic model which takes into account pore diffusion and mass transfer for devolatilization and char oxidation. 9 references, 12 figures.
Date: October 1, 1983
Creator: Pandalai, Krish; Aggarwal, Suresh & Sirignano, William
Partner: UNT Libraries Government Documents Department
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Joining of ceramics for high performance energy systems. Mid-term progress report, August 1, 1979-March 31, 1980

Description: 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
Partner: UNT Libraries Government Documents Department
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Potential for efficient frequency conversion at high average power using solid state nonlinear optical materials

Description: High-average-power frequency conversion using solid state nonlinear materials is discussed. Recent laboratory experience and new developments in design concepts show that current technology, a few tens of watts, may be extended by several orders of magnitude. For example, using KD*P, efficient doubling (>70%) of Nd:YAG at average powers approaching 100 KW is possible; and for doubling to the blue or ultraviolet regions, the average power may approach 1 MW. Configurations using segmented apertures permit essentially unlimited scaling of average power. High average power is achieved by configuring the nonlinear material as a set of thin plates with a large ratio of surface area to volume and by cooling the exposed surfaces with a flowing gas. The design and material fabrication of such a harmonic generator are well within current technology.
Date: October 28, 1985
Creator: Eimerl, D.
Partner: UNT Libraries Government Documents Department
open access

Effect of fuel recycling on radioactivity and thermal power of high-level wastes

Description: The radioactivity and thermal power of high-level and plutonium-bearing wastes from the nuclear fuel cycle have been calculated for the years 1975 to 2005 using the rate of generation of such wastes projected for the Generic Environmental Statement on Mixed Oxide Fuel (NUREG-0002). Three modes of fuel recycle are considered: (1) no recycle, (2) uranium recycle, and (3) prompt uranium and plutonium recycle. These cases are compared with a respect to radioactivity and thermal power of the generated waste, the waste shipments, and the accumulated inventories at reactor sites, reprocessing facilities, and ultimate disposal sites.
Date: October 1, 1977
Creator: Wachter, J.W.
Partner: UNT Libraries Government Documents Department
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The interpretation of reflectometry measurements of plasma fluctuations

Description: Wave reflections from density fluctuations with magnitudes and frequencies typical of drift waves have been investigated. Both drift waves and the reflected phase and amplitude depend on the density gradient scale length, and this common feature implies that both the angular deviation of a normally propagating wave and the phase change on reflection are of order unity. Thus the surface will always appear rough'' and amplitude variations will always be large. For smaller amplitude waves numerical solutions of the one dimensional full wave equation for the propagation near cutoff frequencies has been used to show how to interpret reflectometry measurements. For density perturbations with wavelengths near the density scale length, the external fluctuating phase can be simply interpreted in terms of a fluctuating density near the cutoff layer. However, the amplitude of the phase response falls substantially as the fluctuation wavelength, {Lambda}, approaches the free space wavelength of the reflected wave, {lambda}{sub o}, and the location of the maximum response moves out in front of the cutoff layer following the wave matching condition k{sub {Lambda}} = 2k {approx} 2{eta}(x)k{sub 0}. Similarly, correlation measurements of density fluctuations from probe waves of different wavelengths are shown to be limited to about four times the average reflected wavelength. 12 refs., 9 figs.
Date: October 1, 1991
Creator: Bretz, N.
Partner: UNT Libraries Government Documents Department
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Thermodynamic model for calorimetric and phase coexistence properties of coal derived fluids

Description: On September 1, 1989 work was initiated on a project to extend the available vapor-liquid equilibrium (VLE) model for coal fluids to allow satisfactory predictions of excess enthalpies of coal liquids at high pressures. The available vapor liquid equilibrium model was developed with support from previous grant from DOE-PETC (Grant no. DE-FG22-89PC90541). The current project also involves measurement of some model compound VLE data and chromatographic characterization of coal liquids for distribution of heteroatoms. A computational thermodynamic model for VLE, excess enthalpies and heat capacities of coal derived liquids has been developed. The model uses the modified UNIFAC correlation for the liquid phase. Some unavailable UNIFAC interactions parameters have been regressed from experimental VLE and excess enthalpy data. The computations are carried out using the method of continuous thermodynamics. Mode is used to derive interesting conclusions on the effect of oxygen, nitrogen, and sulfur heteroatoms on the thermodynamic properties of coal liquids. When compared with limited experimental data available for coal liquids the model shows good agreement. Some progress has been made on binary VLE measurements and size exclusion chromatography of coal liquids.
Date: October 1, 1991
Creator: Kabadi, V. N.
Partner: UNT Libraries Government Documents Department
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Laser annealing of ion implanted CZ silicon for solar cell junction formation. Quarterly report No. 2

Description: Results on a contract to evaluate the merits of large spot size pulsed laser annealing of ion implanted silicon wafers for junction formation in solar cells are reported. Investigations on homogenization of the laser beam were continued. In addition to the 30 mm diameter fused silica rod with a 90/sup 0/ bend configuration, quartz tubes were obtained and briefly tried. Best results were obtained with the rod homogenizer. Laser annealing experimentation resulted in complete recrystallization of ion implanted silicon substrates as confirmed by TEM and RBS analysis. Single pulse laser annealed, functional cells (2 x 2cm) were fabricated using varying process conditions, yielding conversion efficiencies predominantly in the 13% to slightly less than 15%.
Date: October 1, 1980
Creator: Katzeff, J. S.
Partner: UNT Libraries Government Documents Department
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Waste Treatment and Disposal Progress Report for June and July 1961

Description: 7 7 6 4 : 9 8 9 6 5 : 9 aluminum nitrate waste was calcined in the close-coupled continuous evaporator-pot calciner unit. Waste oxides from TBP-25 waste were incorporated into glassy materials after the addition of phosphate and borate fluxing agents. Melts formed at 850 to 950 deg C were glassy solids when cooled and had densities from 2.41 to 2.47 g/ml. Waste volurne reduction factors were from 7.6 to 9.3. Low-Level Waste Treatment. A demonstration run was completed in the 60 liters/hr scavenging-ion exchange pilot plant on ORNL low-activity waste. Decontamination factors were satisfactory after 1500 resin bed voluumes of waste had been treated, i. e, Sr> 1000, TRE 100, Cs> 100, and sufficiently high for other activities that the waste activity was reduced to <10% of MPC. The physical properties of vermiculite, clinoptilolite, and rock phosphate were found to be suitable for second-stage treatment of process waste. Engineering, Econommc, and Hazards Evaluation. A cost study of the conversion of high-level solutions to solids by pot calcimation was completed. Aging had a negligible effect on costs for processing in a given vessel size. The lowest cost was 0.87 x 10/sup-2/ mill/kwh/sub 3/ for processing acidic Purex and Thorex wastes in 24-in.-dia. vessels, and the highest was 5.0 x 10/sup -2/ mill/kwh/sub e/ for processing reacidifled Purex and Thorex wastes im 6-in.-dia. vessels. Disposal ion Deep Wells. Test drilling at the site of the second fracturing experiment is nearly completed. The upper grout sheet extends out from the injection well some 500 ft to the east and northeast, but only- short distances out in other directions. The lower grout sheet extends largely to the north and northwest, but its outer limits are still undefimed. Disposal in Natural Salt Formations. Stress measurements in the pillars of the Hutchimson mine …
Date: October 24, 1961
Creator: Blanco, R. E. & Struxness, E. G.
Partner: UNT Libraries Government Documents Department
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