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Assessment of a chemical getter for scavenging tritium from an inert gas

Description: Results are presented of a study aimed at determining the feasibility of using chemical getter beds to scavenge tritium from inert gases. Two types of getter bed, fixed and fluidized, were considered, using cerium as the getter material. Mathematical-modeling results and capital-cost estimates indicate that not only is the gettering approach technically feasible, it could lead to considerable cost savings over catalytic oxidation, the tritium-removal method traditionally used.
Date: May 7, 1976
Creator: Maienschein, J. L.
Partner: UNT Libraries Government Documents Department

Assessment of very high temperature reactors in process applications

Description: In April 1974, the United States Energy Research and Development Administration (ERDA) authorized General Atomic Company, General Electric Company, and Westinghouse Astronuclear Laboratory to assess the available technology for producing process heat utilizing a very high temperature nuclear reactor (VHTR). The VHTR is defined as a gas-cooled graphite-moderated reactor. Oak Ridge National Laboratory has been given a lead role in evaluating the VHTR reactor studies and potential applications of the VHTR. Process temperatures up to the 760 to 871/sup 0/C range appear to be achievable with near-term technology. The major development considerations are high temperature materials, the safety questions (especially regarding the need for an intermediate heat exchanger) and the process heat exchanger. The potential advantages of the VHTR over competing fossil energy sources are conservation of fossil fuels and reduced atmospheric impacts. Costs are developed for nuclear process heat supplied from a 3000-MW(th) VHTR. The range of cost in process applications is competitive with current fossil fuel alternatives.
Date: April 7, 1976
Creator: Jones, J. E. Jr.; Spiewak, I. & Gambill, W. R.
Partner: UNT Libraries Government Documents Department

Collective behavior in recent laser-plasma experiments

Description: The absorption of 1.06 ..mu.. light focused on small C/sub 8/H/sub 8/ discs has been measured in the intensity range of 10/sup 15/ - 10/sup 17/ W/cm. The data confirms the importance of collective plasma effects in determining the absorption of intense light. The measured absorption efficiencies are in the range of 30 to 40 percent, and the scattered light has a polarization dependence. The measured absorptions are shown to be inconsistent with classical inverse bremsstrahlung. Both the magnitude of the absorption and the observed polarization dependence of the scattered light are shown to be consistent with recent calculations of light absorption via collective processes. Comparisons are made, and improved models of the light absorption are discussed with reference to the data. In addition, the heated electron energies deduced from the x-ray data are consistent with those expected via collective processes.
Date: June 7, 1976
Creator: Kruer, W. L.; Haas, R. A.; Mead, W. C.; Phillion, D. W. & Rupert, V. C.
Partner: UNT Libraries Government Documents Department

Cyrtonaias tampicoensis, Specimen #160

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an oval shape; moderately thick shell; single looped beak sculpturing; pink internal coloring; reddish-brown external coloring; no external sculpturing. Collected in the Brazos basin. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: January 7, 1976
Creator: Johnson, L.
Partner: Elm Fork Natural Heritage Museum

Determination of beryllium in urine, hair, fingernail, and fecal samples by flameless atomic absorption spectrometry

Description: Methods for determining trace amounts of beryllium in urine, hair, fingernail, and fecal samples are described. These methods involve use of a Perkin-Elmer Model 503 spectrophotometer equipped with an HGA-2100 graphite furnace. Lanthanum was used as a masking and enhancing agent, and recoveries were determined by direct comparison with aqueous standards. The hair and fingernail samples were degraded readily in a nitric acid-perchloric acid mixture, and the feces were digested rapidly using a ferrous ion, hydrogen peroxide method. The urine samples were run by two methods: (1) direct and (2) coprecipitation. Nanogram-per-gram levels of beryllium were recovered from all tissues and fluids. All recoveries varied from 90 to 110 percent with relative standard deviations of less than 13 percent.
Date: May 7, 1976
Creator: Hurlbut, J. A.
Partner: UNT Libraries Government Documents Department

Evaluation of the Amperex 56 TVP photomultiplier

Description: Characteristics have been measured for the Amperex 56 TVP 42-mm-diameter photomultiplier. Some typical photomultiplier characteristics--such as gain, dark current, transit and rise times--are compared with data provided by the manufacturer. Photomultiplier characteristics generally not available from the manufacturer, such as the single photoelectron time spread, the relative collection efficiency, the relative anode pulse amplitude as a function of the voltage between the photocathode and focusing electrode, and the position of the photocathode sensing area were measured and are discussed for two 56 TVP's. The single photoelectron time spread, the relative collection efficiency, and the transit time difference as a function of the voltage between photocathode and focusing electrode were also measured and are discussed, particularly with respect to the optimization of photomultiplier operating conditions for timing applications.
Date: July 7, 1976
Creator: Lo, C. C. & Leskovar, B.
Partner: UNT Libraries Government Documents Department

Experimental observations on long pulse intense ion diode operation

Description: An experiment in which a long pulse electron beam diode is converted to a reflex ion diode is reported. The results further substantiate the model of reflex ion diode behavior as well as extend the duration of ion mode operation to greater than 500 nsec.
Date: July 7, 1976
Creator: Prono, D. S.; Clark, R. & Prestwich, K.
Partner: UNT Libraries Government Documents Department

Feasibility of storing radioactive wastes in Columbia River basalts

Description: In 1968 Atlantic Richfield Hanford Company initiated a study to assess the feasibility of final geologic storage of Hanford defense, radioactive waste in deep caverns constructed in the Columbia River flood basalts. The project, which included geologic studies, hydrologic tests, heat flow analysis, compatibility analysis, and tectonic studies, was suspended in 1972 before completion of interpretive work. In 1976 the interpretation and documentation were completed. These data may be valuable in qualifying the Columbia River flood basalts as a viable medium for final geologic storage of commercial radioactive waste. The findings to date are summarized, and the proposed future work is presented. (LK)
Date: December 7, 1976
Creator: Deju, R. A.
Partner: UNT Libraries Government Documents Department

Flameless atomic absorption determination of beryllium in the presence of various anions and cations

Description: A method for determining trace amounts of beryllium in the presence of various anions and cations is described. The method involves use of a Perkin-Elmer Model 503 spectrophotometer equipped with an HGA-2100 graphite furnace. The absorption signal from 20 ng/ml of beryllium varies significantly from acid to acid, and both 5 percent (V/V) nitric acid and 5 percent (V/V) sulfuric acid were studied as possible analysis solvents. Absorption signal enhancement and suppression caused by the presence of other chemicals appears similar in either solvent. Concentrations of more than 0.1M hydrochloric and hydrofluoric acid suppress the signal in both solvents. Group II cations, lanthanum, cerium, chromium, molybdenum, tungsten, manganese, aluminum, and silicon, when present in concentrations of 100 ..mu..g/ml, enhance the beryllium signal. The addition of 100 ..mu..g/ml of lanthanum increases the signal over two fold and masks the signal enhancement caused by the other listed elements; however, hydrochloric and hydrofluoric acids still interfere. The recovery of 20 ng/ml of beryllium in the presence of 100 ..mu..g/ml of lanthanum and in the presence of 100 ..mu..g/ml each of thirty elements tested is 20 ..mu..g/ml with a relative standard deviation of 4 percent and a range of 19 to 22 ng/ml. The presence of lanthanum permits direct detection of less than 1 ng/ml of beryllium in urine.
Date: May 7, 1976
Creator: Hurlbut, J. A. & Bokowski, D. L.
Partner: UNT Libraries Government Documents Department

Flash x-ray. [Nondestructive testing of material that is moving or changing very rapidly]

Description: The complementary techniques of flash x-ray radiography (FXR) and flash x-ray diffraction (FXD) provide access to a unique domain in nondestructive materials testing. FXR is useful in studies of macroscopic properties during extremely short time intervals, and FXD, the newer technique, is used in studies of microscopic properties. Although these techniques are similar in many respects, there are some substantial differences. FXD generally requires low-voltage, line-radiation sources and extremely accurate timing; FXR is usually less demanding. Phenomena which can be profitably studied by FXR often can also be studied by FXD to permit a complete materials characterization.
Date: September 7, 1976
Creator: Johnson, Q. & Pellinen, D.
Partner: UNT Libraries Government Documents Department

Laser-generated stress pulses for material-response studies

Description: Experimental techniques for the generation of stress pulses of submicrosecond duration, in the form of uniaxial strain waves, were developed by absorbing the radiation from a Q-switched laser in thin films of liquids and solids resting on hard steel substrates. The experiments employed pulses of radiation at a wavelength of 1.06 ..mu..m, with a duration of about 30 ns at half maximum power and fluences from 8 to 13 J/cm/sup 2/. The stress waves produced in the steel substrates were measured by means of x-cut quartz piezoelectric gages. The typical stress pulse consisted of a rapid rise to a peak value followed by a slower delay over a period of about one-quarter microsecond. The maximum stress generated with a liquid absorber was 3.4 kbar when a solution of cupric chloride in water was irradiated with a fluence of 8 J/cm/sup 2/. A peak stress of 15 kbar was obtained with a 1-..mu..m-thick layer of aluminum under glass and a fluence of 8 J/cm/sup 2/.
Date: September 7, 1976
Creator: Wood, D. S. & Wilcox, W. W.
Partner: UNT Libraries Government Documents Department

MHSS: a material handling system simulator

Description: A Material Handling System Simulator (MHSS) program is described that provides specialized functional blocks for modeling and simulation of nuclear material handling systems. Models of nuclear fuel fabrication plants may be built using functional blocks that simulate material receiving, storage, transport, inventory, processing, and shipping operations as well as the control and reporting tasks of operators or on-line computers. Blocks are also provided that allow the user to observe and gather statistical information on the dynamic behavior of simulated plants over single or replicated runs. Although it is currently being developed for the nuclear materials handling application, MHSS can be adapted to other industries in which material accountability is important. In this paper, emphasis is on the simulation methodology of the MHSS program with application to the nuclear material safeguards problem. (auth)
Date: April 7, 1976
Creator: Pomernacki, L. & Hollstien, R. B.
Partner: UNT Libraries Government Documents Department

Oral History Interview with Stanton H. Enchelmeyer, April 7, 1976

Description: Interview with Army Air Corps veteran Stanton H. Echelmeyer. The interview includes Echelmeyer's personal experiences at Hickam Field with the 50th Reconnaissance Squadron during the Japanese attack at Pearl Harbor on December 7, 1941.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: April 7, 1976
Creator: Marcello, Ronald E. & Echelmeyer, Stanton H.
Partner: UNT Oral History Program

Pockels cell pulse-stackers

Description: The general transmission characteristics of a pulse-stacking system consisting of an etalon and a cylindrical-ring electrode Pockels cell Q-switch are discussed. A voltage pulse-forming network capable of switching the Pockels cell transmission on the necessary time scales is presented and the outputs of a simple pulse-stacker configuration are calculated for different voltage waveforms. These results indicate that an efficient (approximately 1 percent total pulse energy transmission) Pockels cell pulse-stacker can be constructed, which can provide a variable, faster-than-exponential rise in transmitted pulse intensity.
Date: January 7, 1976
Creator: Harney, R. C.
Partner: UNT Libraries Government Documents Department

Preparation of microspherical alpha-radiation sources. [/sup 238/Pu; /sup 22/Na]

Description: Sodium silicate glass microspheres in the 105-125 ..mu..m diameter size range, containing in vitreous solution the radioisotopes plutonium-238 and sodium-22, were prepared in four batches which emitted a nominal 40, 80, 320, and 640 nCi of total alpha radiation and approximately 1 nCi of gamma radiation form the sodium-22 isotope from each sphere. The initial integrity of the glasses was good and no wipeable contamination was detected from the spheres. The alpha particle range in the glass for the 5.5-MeV alpha particle emitted by plutonium-238 was calculated to be 15.2 ..mu..m, based upon radiometric analysis of individual spheres from each batch of product. (auth)
Date: May 7, 1976
Creator: Wittenberg, L. J.
Partner: UNT Libraries Government Documents Department

SPE water electrolysis technology development for large scale hydrogen production. Progress report No. 4, June 15, 1976--September 30, 1976

Description: 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 to 45 percent graft level range. In the cell and SPE optimization work, initial testing of cells with tandem (anion/cation monobed followed by cation only) deionizers show improved voltage invariance. Evaluation of a hydraulically loaded cell test fixture which eliminates gaskets and gives uniform cell compression was completed. Hydraulic fixtures are being factored into the low cost current collector and high temperature operation tasks.
Date: October 7, 1976
Partner: UNT Libraries Government Documents Department

Standpipe-Bubbler pump level control study: 1E-3862, controlled clearance pump/system model analysis (Task A) W. P. 7373. Engineering memorandum 0190. [LMFBR]

Description: Computer simulation results of the Standpipe-Bubbler pump level control system/controlled clearance pump configuration 1E-3862 are presented. Fluid level control system behavior is presented in graphical form for normal plant loading, unloading, and trip transients, under varying conditions of cover gas mass flow rate, tank impedances, temperature, and flow rates through discharge seal and bearing leakage paths. Satisfactory fluid level control can be attained for this configuration with a Standpipe-Bubbler system.
Date: June 7, 1976
Creator: Salant, R.F. & Cook, M.E.
Partner: UNT Libraries Government Documents Department

Temperature tests of high frequency SLIFER oscillator, LEA73-2176. [For monitoring underground nuclear detonations at Nevada Test Site]

Description: SLIFER (Short Location Indication by Frequency of Electrical Resonance) systems measure stress wave velocity in solid or liquid materials. They monitor underground nuclear detonations at the Nevada Test Site (NTS). A shorted length of coaxial cable is a component in an oscillator's tank circuit. This sensor cable is inductive when less than one-fourth wavelength long at the oscillator's resonant frequency. The stress wave from a detonation crushes and shorts this sensor cable. As the short proceeds, inductance decreases and oscillator frequency increases. Later we convert frequency vs time to shock-front position vs time. Some doubt existed about the reliable operation of the oscillators in cold weather. Therefore these tests were conducted to check their reliability under several conditions: (1) at temperatures from -40/sup 0/ to 60/sup 0/C; (2) with three sensor cable lengths; (3) with sensor cables shorted or open at the far end; and (4) at two input power voltages. Results are presented.
Date: June 7, 1976
Creator: Aaron, Carl C., Jr.
Partner: UNT Libraries Government Documents Department