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High-pressure tritium equipment

Description: Some solutions to problems of compressing and containing tritium gas to 200 MPa at 700 K are discussed The principal emphasis is on commercial compressors and high-pressure equipment that can be modified easily by the researcher for safe use with tritium. Experience with metal belows and diaphragm compressors has been favorable. Selection of materials, fittings and gauges for high- pressure tritium work also is reviewed briefly.
Date: December 31, 1976
Creator: Coffin, D.O.
Partner: UNT Libraries Government Documents Department

Second workshop geothermal reservoir engineering: Proceedings

Description: The Arab oil embargo of 1973 focused national attention on energy problems. A national focus on development of energy sources alternative to consumption of hydrocarbons led to the initiation of research studies of reservoir engineering of geothermal systems, funded by the National Science Foundation. At that time it appeared that only two significant reservoir engineering studies of geothermal reservoirs had been completed. Many meetings concerning development of geothermal resources were held from 1973 through the date of the first Stanford Geothermal Reservoir Engineering workshop December 15-17, 1975. These meetings were similar in that many reports dealt with the objectives of planned research projects rather than with results. The first reservoir engineering workshop held under the Stanford Geothermal Program was singular in that for the first time most participants were reporting on progress inactive research programs rather than on work planned. This was true for both laboratory experimental studies and for field experiments in producing geothermal systems. The Proceedings of the December 1975 workshop (SGP-TR-12) is a remarkable document in that results of both field operations and laboratory studies were freely presented and exchanged by all participants. With this in mind the second reservoir engineering workshop was planned for December 1976. The objectives were again two-fold. First, the workshop was designed as a forum to bring together researchers active in various physical and mathematical branches of the developing field of geothermal reservoir engineering, to give participants a current and updated view of progress being made in the field. The second purpose was to prepare this Proceedings of Summaries documenting the state of the art as of December 1976. The proceedings will be distributed to all interested members of the geothermal community involved in the development and utilization of the geothermal resources in the world. Many notable occurrences took place between the ...
Date: December 3, 1976
Creator: Kruger, P. & Ramey, H.J. Jr. (eds.)
Partner: UNT Libraries Government Documents Department

The Effects of a Step Change in Water Flow on an Initially Linear Profile of Temperature

Description: In recent analyses of the hot-water system at Wairakei, New Zealand (Mercer, Pinder, and Donaldson, 1975) and the vapor-dominated system at Larderello, Italy (Petracco and Squarci, 1975), it has been suggested that large quantities of cold water are entering the reservoir by flowing down from the surface and then horizontally into the reservoir because of decreased reservoir pressures. It is also suggested that decreased reservoir pressures should increase these downward flows above their pre-exploitation levels. In order to estimate the effects of vertical flows on the temperature distribution, two idealized problems are analyzed in this paper. In both problems, the initial condition is a linear temperature increase with depth, and the flow starts at time equal to zero. In the first problem, the flow is through a semi-confining layer with the temperature fixed at the top and bottom of the layer. In the second problem, the flow is into a half-space with the surface temperature fixed. The magnitudes of the effects for the two cases considered suggest that monitoring temperatures in undisturbed wells on the margins of producing geothermal areas should give a measure of the change in the fairly local recharge. If the amount of total recharge is known, subtracting the localized recharge should give an estimate of the recharge derived from deep circulation that originates at large distances from the reservoir. 7 refs., 2 figs.
Date: December 1, 1976
Creator: Nathenson, Manuel
Partner: UNT Libraries Government Documents Department

Laboratory Experiments on Hydrofracture and the Permeability of Hot Granite

Description: It has been proposed that an artificial geothermal reservoir could be created by injecting water under high pressure through a hole drilled into a hot dry batholith. By drilling a second hole to intersect the plane created by hydraulic fracture, a fluid circulation system could be created by pumping cold water into one hole and extracting hot water or steam through the other hole. The authors have carried out a number of laboratory experiments to investigate various aspects of this project. While it is usually assumed that a single tension hydraulic fracture is formed with its plane parallel to the direction of maximum principal stress, the authors have found in laboratory experiments that, if the rock is under shear stress and the fluid is injected slowly enough, shear fractures are formed with their planes oriented about 30 degrees to the direction of maximum principal stress. The results suggest that it may be possible, in regions of high tectonic stress, to increase the fracture surface area simply by varying the fluid injection rate to create not only a tension fracture but shear fractures as well. The authors found that the spacial distribution of the fracture planes is accurately determinable from the location of the acoustic emission events that occur during fracture. The authors state that this distribution should also be calculable from the change in magnetic field at the earth's surface caused by the injection of high-magnetic-susceptibility material into the fracture. Results are described of measurements of the permeability of granite under confining pressure and differential stress at temperatures to 400ÂșC, along with how they relate to the way a circulating system's permeability changes with time. 4 refs.
Date: December 1, 1976
Creator: Byerlee, J.; Lockner, D. & Summers, R.
Partner: UNT Libraries Government Documents Department

Enzymes and microorganisms in food industry waste processing and conversion to useful products: a review of the literature

Description: Bioconversion of food processing wastes is receiving increased attention with the realization that waste components represent an available and utilizable resource for conversion to useful products. Liquid wastes are characterized as dilute streams containing sugars, starches, proteins, and fats. Solid wastes are generally cellulosic, but may contain other biopolymers. The greatest potential for economic bioconversion is represented by processes to convert cellulose to glucose, glucose to alcohol and protein, starch to invert sugar, and dilute waste streams to methane by anaerobic digestion. Microbial or enzymatic processes to accomplish these conversions are described.
Date: December 1, 1976
Creator: Carroad, P.A. & Wilke, C.R.
Partner: UNT Libraries Government Documents Department

Total hadron cross section, new particles, and muon electron events in e/sup +/e/sup -/ annihilation at SPEAR

Description: The review of total hadron electroproduction cross sections, the new states, and the muon--electron events includes large amount of information on hadron structure, nine states with width ranging from 10's of keV to many MeV, the principal decay modes and quantum numbers of some of the states, and limits on charm particle production. 13 references. (JFP)
Date: January 1, 1976
Creator: Richter, B.
Partner: UNT Libraries Government Documents Department

Proceedings of particles and fields, 1976

Description: The conference contained 23 papers, two of which appeared previously in ERA. Separate abstracts were prepared for 21 papers. (JFP)
Date: January 1, 1976
Creator: Gordon, H. & Peierls, R.F. (eds.)
Partner: UNT Libraries Government Documents Department

Leak detection system design and operating considerations for the US-CRBRP

Description: Diffusion membrane type hydrogen detectors are provided for monitoring the sodium exiting each evaporator and superheater in the Clinch River Breeder Reactor Plant. These detectors allow detection of small water to sodium leaks and provide the plant operator with an early warning signal. Hydrogen detectors are located at the exit sodium streams of each steam generator module, the vent from the module semi-stagnant region, the cold leg piping, and in an intermediate system sodium expansion tank cover gas region. In addition, an electrochemical oxygen detector is located in the cold leg piping. The leak detection system is capable of detecting the presence of steam/water leaks on the order of 0.45 x 10/sup -5/ kg/sec or larger and of signaling within one to three minutes upon initiation of a leak, during normal operation. Operator action is taken upon receipt of a leak signal to shutdown the affected system, by closing steam/water isolation valves and depressurizing the affected unit.
Date: January 1, 1976
Creator: Kruger, G.B.; Eng, K.Y. & Kelly, W.L.
Partner: UNT Libraries Government Documents Department

Engineering problems in the development of fusion power reactors

Description: This paper reviews current progress in the development of fusion power from the engineering point of view and highlights the most outstanding technical issues which must be resolved. (MOW)
Date: November 2, 1976
Creator: Varljen, T. C.
Partner: UNT Libraries Government Documents Department

Design of the US-CRBRP sodium/water reaction pressure relief system

Description: Protection against intermediate sodium system overpressure from the sodium/water reaction associated with large leaks within the CRBRP Steam Generators is provided by the sodium/water reaction pressure relief system (SWRPRS). This system consists of rupture disks connected to the intermediate sodium piping adjacent to the inlet to the superheater and outlet from the evaporator modules. The rupture discs relieve into piping that leads to reaction produce separator tanks, which in turn are vented to a centrifugal separator and flare stack arranged to burn hydrogen gas exhausting into the atmosphere. Analyses have been conducted using the TRANSWRAP Computer Code to predict the system pressures and flow rates during the large leak event. Experimental tests to be conducted in the large leak test rig (LLTR) will be used to confirm the analysis techniques used in the design.
Date: January 1, 1976
Creator: Kruger, G.B.; Murdock, T.B.; Rodwell, E. & Sane, J.O.
Partner: UNT Libraries Government Documents Department

Radiation blistering of Nb implanted sequentially with helium ions of different energies (3-500 keV)

Description: Cold rolled, polycrystalline niobium samples were irradiated at room temperature with $sup 4$He$sup +$ ions sequentially at 14 different energies over an energy range from 3 keV--500 keV in steps of 50 keV. The dose for each energy was chosen to give an approximately uniform concentration of helium between the implant depths corresponding to 3 keV and 500 keV. In one set of experiments the irradiations were started at the Kurchatov Institute with 3 keV $sup 4$He$sup +$ ions and extended up to 80 keV in several steps. Subsequently, the same target area was irradiated with $sup 4$He$sup +$ ions at Argonne National Laboratory (ANL) starting at 100 keV and increased to 500 keV in steps of 50 keV. Another set of irradiations were started at ANL with 500 keV $sup 4$He$sup +$ ions and continued with decreasing ion energies to 100 keV. Subsequently, the same area was irradiated at the Kurchatov Institute starting at 80 keV and continued with decreasing ion energies to 3 keV. Both sets of irradiations were completed for two different total doses, 0.5 C cm$sup -2$ and 1.0 C cm$sup -2$.
Date: January 1, 1976
Creator: Guseva, M.I.; Gusev, V.; Krasulin, U.L.; Martinenko, U.V.; Das, S.K. & Kaminsky, M.S.
Partner: UNT Libraries Government Documents Department

Energy flux limitation by tame turbulence

Description: A quasi-linear theory of energy flux limitation by ion acoustic turbulence is presented. This distribution function is modelled by a Maxwellian plus an additional piece which carries a heat flux Q. By taking the fourth moment of the Vlasov equation one finds the anomalous thermal conductivity K approximately 3 v/sub e/ lambda/sub De/ (e phi/T/sub e/)$sup -2$. Other moments treated self-consistently include anomalous ion heating, electron cooling, current generation and enhanced inverse bremsstrahlung due to the nonthermal ion fluctuations. (auth)
Date: February 1, 1976
Creator: Manheimer, W.M.
Partner: UNT Libraries Government Documents Department

Reduction of surface erosion caused by helium blistering in sintered beryllium and sintered aluminum powder

Description: Studies have been conducted to find materials with microstructures which minimize the formation of blisters. A promising class of materials appears to be sintered metal powder with small average grain sizes and low atomic number Z. Studies of the surface erosion of sintered aluminum powder (SAP 895) and of aluminum held at 400$sup 0$C due to blistering by 100 keV helium ions have been conducted and the results are compared to those obtained earlier for room temperature irradiation. A significant reduction of the erosion rate in SAP 895 in comparison to annealed aluminum and SAP 930 is observed. In addition results on the blistering of sintered beryllium powder (type I) irradiated at room temperature and 600$sup 0$C by 100 keV helium ions are given. These results will be compared with those reported recently for vacuum cast beryllium foil and a foil of sintered beryllium powder (type II) which was fabricated differently, than type I. For room temperature irradiation only a few blisters could be observed in sintered beryllium powder type I and type II and they are smaller in size and in number than in vacuum cast beryllium. For irradiation at 600$sup 0$C large scale exfoliation of blisters was observed for vacuum cast beryllium but much less exfoliation was seen for sintered beryllium powder, type I, and type II. The results show a reduction in erosion rate cast beryllium, for both room temperature and 600$sup 0$C.
Date: January 1, 1976
Creator: Das, S.K. & Kaminsky, M.
Partner: UNT Libraries Government Documents Department

Correlation between blister skin thickness, the maximum in the damage- energy distribution, and projected ranges of helium ions in Nb for the energy range 10 to 1500 keV

Description: The skin thickness of blisters formed on polycrystalline niobium by $sup 4$He$sup +$ irradiation at room temperature for energies from 15 to 80 keV have been measured. Similar measurements were conducted for 10 keV $sup 4$He$sup +$ irradiation at 500$sup 0$C to increase blister exfoliation, and thereby allow examination of a larger number of blister skins. For energies smaller than 100 keV the skin thicknesses are compared with the projected range and the damage- energy distributions constructed from moments interpolated from Winterbon's tabulated values. For energies of 10 and 15 keV the projected ranges and damage- energy distributions have also been computed with a Monte Carlo program. For energies larger than 100 keV the projected ranges of $sup 4$He$sup +$ in Nb were calculated using either Brice's formalism or the one given by Schiott. The thicknesses for 60 and 80 keV, and those reported earlier for 100 to 1500 keV correlate well with calculated projected ranges. For energies lower than 60 keV the measured thicknesses are larger than the calculated ranges.
Date: January 1, 1976
Creator: St-Jacques, R.G.; Martel, J.G.; Terreault, B.; Veilleux, G.; Das, S.K.; Kaminsky, M. et al.
Partner: UNT Libraries Government Documents Department

Stress distribution in helium-ion implantations

Description: The stress introduced into a material in a monoenergetic helium-ion implantation is calculated for an ion beam with a gaussian intensity distribution. An effective beam spot of the order of several millimeters was chosen as typical of blistering experiments. The sample is assumed to be semi-infinite and isotropic. The ion distribution is cylindrically symmetric with a gaussian depth profile. The parameters defining the distribution are consistent with incident ion energies of approximately 40 and approximately 400 keV in both nickel and niobium. The volume expansion caused by the implanted ions is assumed to be proportional to the local helium concentration; the validity of this assumption is discussed. The maximum shear stress is calculated as a function of depth, and the volume expansion per helium atom required to produce plastic deformation at the experimentally observed critical doses in niobium is found to be of the order of one atomic volume.
Date: January 1, 1976
Creator: Hall, B. O.
Partner: UNT Libraries Government Documents Department

MHD equilibrium properties of tokamak fusion reactor designs

Description: The equilibrium properties of several Tokamak Reactor Designs are analyzed and compared for varying pressure and current profiles using the Princeton Equilibrium Code. It is found that the UWMAK configuration has a broader range of equilibria than the Princeton Reference Design configuration, but that the safety factor on axis is less than unity for peaked current distributions. The Argonne Experimental Power Reactor has a satisfactory range of equilibria, but a means of limiting or diverting the plasma has not yet been proposed, and this may substantially change the results obtained. (auth)
Date: January 1, 1976
Creator: Todd, A. M.M.; Gralnick, S. L. & Dalhed, H. E.
Partner: UNT Libraries Government Documents Department

Separation of trivalent lanthanides and actinides by solvent extraction without aqueous complexing agents

Description: A method of separating the trivalent actinides, mainly Am and Cm, from trivalent lanthanides is presented. This method embodies the sequential use of two different solvent extractants; the first extractant would remove the heavy lanthanides from the lighter lanthanides and Am--Cm, while the second would extract Am--Cm in preference to the lighter lanthanides. In this scheme, no additional complexing agents are required. Thus, waste disposal and corrosion problems are minimized. Overall separation factors for Am--Cm from lanthanide fission products in reactor wastes may be as high as several thousand. (auth)
Date: January 30, 1976
Creator: Kasting, G.B.; Heppert, J.A.; Hulet, E.K. & Wild, J.F.
Partner: UNT Libraries Government Documents Department

Simplified scheme or radioactive plume calculations

Description: A simplified mathematical scheme to estimate external whole-body $gamma$ radiation exposure rates from gaseous radioactive plumes was developed for the Rio Blanco Gas Field Nuclear Stimulation Experiment. The method enables one to calculate swiftly, in the field, downwind exposure rates knowing the meteorological conditions and $gamma$ radiation exposure rates measured by detectors positioned near the plume source. The method is straightforward and easy to use under field conditions without the help of mini-computers. It is applicable to a wide range of radioactive plume situations. It should be noted that the Rio Blanco experiment was detonated on May 17, 1973, and no seep or release of radioactive material occurred. (auth)
Date: November 21, 1976
Creator: Gibson, T.A. & Montan, D.N.
Partner: UNT Libraries Government Documents Department

Comparison of positron tomography and scintigraphy with $sup 201$Tl for delineation of the myocardium

Description: Recent advances in nuclear medicine instrumentation have led to the development of improved positron-imaging systems which exceed in performance the earlier systems which were limited mainly by low count rate capability. This has led to renewed interest in positron imaging in general, primarily because such devices offer better resolution and higher sensitivity than conventional, mechanically collimated gamma cameras, as well as tomographic capability which may provide additional and more accurate information for the clinician. Furthermore, the unique capabilities of positrons for use in reconstructive imaging are beginning to be exploited. In the present report, results are presented from a preliminary study in which longitudinal tomographic myocardial images, produced with $sup 81$Rb as the positron-emitting label using the double camera coincidence system are compared with conventional myocardial images obtained with $sup 201$Tl and a gamma camera. (auth)
Date: January 1, 1976
Creator: Fill, H.; Buchin, M.; Harper, P.V.; Muehllehner, G.; Walsh, W.; Resnekov, L. et al.
Partner: UNT Libraries Government Documents Department

Personnel exposure experience related to use of $sup 252$Cf sources

Description: Studies are presented of personnel exposures to $sup 252$Cf neutrons and gamma radiation during dosimetry experiments in mouse phantoms, fission foil detectors, and small tissue equivalent ionization chambers. Sensitivity of film badge emulsions to observed levels of $sup 252$Cf neutrons is discussed. Long- term personnel exposure histories are presented. Comparisons are made between neutron dose calculated from observed neutron-gamma ratios and the dose observed in neutron emulsions. Shielding used during experiments is described. (auth)
Date: January 1, 1976
Creator: Mason, E.W.; Moser, F. & Lanzl, L.H.
Partner: UNT Libraries Government Documents Department

Sputtering of vanadium and niobium under 14.1 MeV neutron impact

Description: The recent studies of particle emission from cold-rolled and annealed niobium under 14.1-MeV neutron impact were extended to a heavily etched, polycrystalline niobium surface and to cold worked vanadium surfaces with different degrees of microstructure. The type and amount of material released and deposited on collector surfaces facing the irradiated targets were determined by three analytical techniques. Two types of deposits were found for certain types of surfaces--one in the form of chunks; the other as a fractional atom layer covering the surface. The chunks vary significantly in size. The small number of chunks observed suggests that the ejection of chunks is a relatively rare event in comparison to the total number of primary knock-on events produced by 14-MeV neutrons in near surface regions. Estimates of the total sputtering yield based on the chunk deposits and on the fractional atom layer deposit will be given. (auth)
Date: January 1, 1976
Creator: Kaminsky, M. & Das, S.K.
Partner: UNT Libraries Government Documents Department

Deuteron and helium ion irradiation of ceramic coatings on Nb--1% Zr

Description: The surface damage to insulating barium alumino-silicate glass coatings due to irradiation by 100 and 250 keV deuterons and helium ions at room temperature and at 300$sup 0$C has been studied. Blisters are observed after irradiation at room temperature with both deuterons and helium ions with energies of 100 and 250 keV. For deuteron irradiation a large fraction of the blisters have diameters which are approximately 3 to 5 times larger than the diameter observed with helium ions for identical irradiation conditions, but the density of blisters is nearly an order of magnitude lower. For irradiation at 300$sup 0$C, no blisters are observed with either type of particle. The sharp rise in permeation rate with temperature is thought to be responsible for this behavior. The blister skin thicknesses have been measured and correlated with calculated projected-range values.
Date: January 1, 1976
Creator: Rossing, T.D.; Kaminsky, M. & Das, S.K.
Partner: UNT Libraries Government Documents Department