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Analytical prediction and experimental verification of reactor safety system injection transient

Description: This paper describes the computer code that was developed for thermal hydraulic transient analysis of mixed phase fluid system and the flow tests that were carried out to validate the Code. A full scale test facility was designed to duplicate the Supplementary Shutdown System (SSS) of Savannah River Production Reactors. Several steady state and dynamic flow tests were conducted simulating the actual reactor injection transients. A dynamic multiphase fluid flow code was developed and validated with experimental results and utilized for system performance predictions and development of technical specifications for reactors. 3 refs.
Date: January 1, 1991
Creator: Roy, B.N. & Nomm, E.
Partner: UNT Libraries Government Documents Department
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Compact-Toroid Fusion Reactor (CTOR) based on the Field-Reversed Theta Pinch

Description: Scoping studies of a translating Compact Torus Reactor (CTOR) have been made on the basis of a dynamic plasma model and an overall systems approach. This CTOR embodiment uses a Field-Reversed Theta Pinch as a plasma source. The field-reversed plasmoid would be formed and compressionally heated to ignition prior to injection into and translation through a linear burn chamber, thereby removing the high-technology plamoid source from the hostile reactor environment. Stabilization of the field-reversed plasmoid would be provided by a passive conducting shell located outside the high-temperature blanket but within the low-field superconducting magnets and associated radition shielding. On the basis of this batch-burn but thermally steady-state approach, a reactor concept emerges with a length below approx. 40 m that generates 300 to 400 MWe of net electrical power with a recirculating power fraction less than 0.15.
Date: January 1, 1981
Creator: Hagenson, R.L. & Krakowski, R.A.
Partner: UNT Libraries Government Documents Department
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Hydraulic and thermal properties of soil samples from the buried waste test facility

Description: In shallow land burial, the most common disposal method for low-level waste, waste containers are placed in shallow trenches and covered with natural sediment material. To design such a facility requires an in-depth understanding of the infiltration and evaporation processes taking place at the soil surface and the effect these processes have on the amount of water cycling through a burial zone. At the DOE Hanford Site in Richland, Washington, a field installation called the Buried Waste Test Facility (BWTF) has been constructed to study unsaturated soil water and contaminant transport. PNL is collecting data at the BWTF to help explain soil water movement at shallow depths, and specifically evaporation from bare sols. The data presented here represent the initial phase of a cooperative effort between PNL and Washington State University to use data collected at the BWFT.
Date: October 1, 1981
Creator: Cass, A.; Campbell, G.S. & Jones, T.L.
Partner: UNT Libraries Government Documents Department
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Subharmonic buncher for the Los Alamos free-electron laser oscillator experiment

Description: A high efficiency free-electron laser oscillator experiment is being constructed at Los Alamos National Laboratory. A buncher system has been designed to deliver 30-ps, 5-nC electron bunches to a 20-MeV standing-wave linac at the 60th subharmonic of the 1300-MHz accelerator frequency. The first 108.3-MHz buncher cavity accepts a 5-ns, 5-A peak current pulse from a triode gun. Following a 120-cm drift space, a second 108.3-MHz cavity is used, primarily to enhance the bunching of the trailing half of the bunch. A 1300-MHz cavity with 20-cm drift spaces at the each end completes the beamline components. The bunching process continues into the linac's first three accelerating cells. Two thin iron-shielded lenses and several large-diameter solenoids provide axial magnetic fields for radial focusing.
Date: January 1, 1983
Creator: Fraser, J.S.
Partner: UNT Libraries Government Documents Department
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Effect of phosphorus on the swelling and precipitation behavior of austenitic stainless steels during irradiation

Description: It has been observed that increasing the volume fraction of the needle-shaped iron phosphide phase in austenitic stainless steels tends to inhibit void swelling during neutron irradiation. An earlier analysis showed that this effect could not be accounted for in terms of enhanced point defect recombination at particle-matrix interfaces. The behavior of the iron phosphide phase has been further examined using dual ion beam irradiations. It was found that the particle-matrix interface serves as a site for the nucleation of a very fine dispersion of helium bubbles. It is thought that since a high number density of cavities lowers the number of helium atoms per cavity, the irradiation time for the cavities to accumulate the critical number of gas atoms for bias-driven growth is correspondingly increased. Although the phosphide phase nucleates rapidly, it eventually undergoes dissolution if either the G or Laves phase develops with increasing dose.
Date: January 1, 1983
Creator: Lee, E.H.; Mansur, L.K. & Rowcliffe, A.F.
Partner: UNT Libraries Government Documents Department
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Constructing a bit string universe. Progress report

Description: We present a case for discrete, constructive physics that generates four scale constants, a connection to laboratory events and scattering theory that ties these to the dimensional constants c, h, m/sub p/, and G, and a tentative quantum number assignment consistent with standard model for leptons and quarks with three generations. Current first approximations from the theory are dirac constant c/e/sup 2/ = 137 +- O(1/137), dirac constant c/Gm/sup 2//sub p/ - 2/sup 127/ + 136 approx. = 1.7 x 10/sup 38/(1 +- 0(1/137)), and m/sub p//m/sub e/ = 1836.151497... +-. Our understanding of wave-particle dualism and observational cosmology creates no more experimental paradoxes than currently accepted views - perhaps fewer. 19 references.
Date: February 1, 1984
Creator: Noyes, H.P.; Manthey, M.J. & Gefwert, C.
Partner: UNT Libraries Government Documents Department
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X-ray characterization of oxidized tantalum nitride

Description: Sputter deposited non-stoichiometric tantalum nitride films are oxidized in air between 200 and 500{degrees}C to form a passive film. The oxidized films have been studied with x-ray absorption near edge spectroscopy (XANES) and extended x-ray absorption near edge spectroscopy (EXAFS). Films exposed to KOH formed a non-protective surface layer identified in low angle XANES and EXAFS as KTaO{sub 3}. Auger electron and x-ray photoelectron spectroscopies were also used to characterize these films.
Date: January 1, 1991
Creator: MaSaitis, R.L.; Opila, R.L. (AT and T Bell Labs., Murray Hill, NJ (United States)); Ibidunni, A.O. (AT and T Bell Labs., North Andover, MA (United States)); Davenport, A.J. & Isaacs, H.S. (Brookhaven National Lab., Upton, NY (United States))
Partner: UNT Libraries Government Documents Department
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Radioactive Fallout From the Chernobyl Nuclear Reactor Accident

Description: This report describes the detection of fallout in the United States from the Chernobyl nuclear reactor accident. As part of its environmental surveillance program, Lawrence Livermore National Laboratory maintained detectors for gamma-emitting radionuclides. Following the reactor accident, additional air filters were set out. Several uncommon isotopes were detected at the time the plume passed into the US. (TEM)
Date: August 1, 1987
Creator: Beiriger, J. M.; Failor, R. A.; Marsh, K. V. & Shaw, G. E.
Partner: UNT Libraries Government Documents Department
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The ALS -- A high-brightness XUV synchrotron radiation source

Description: The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory is scheduled to be operational in the spring of 1993 as a US Department of Energy national user facility. The ALS will be a next-generation source of soft x-ray and ultraviolet (XUV) synchrotron radiation. Undulators will provide high-brightness radiation oat photon energies from below 10 eV to above 2 keV; wiggler and bend-magnet radiation will extend the spectral coverage with high fluxes approaching 20 keV. The ALS will support an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms. the high brightness will open new areas of research from the materials sciences, such as spatially resolved spectroscopy, to the life sciences, such as x-ray microscopy with element-specific sensitivity. Experimental facilities (insertion devices, beamlines, and end stations) will be developed and operated by participating research teams working with the ALS staff. 6 refs., 2 figs., 2 tabs.
Date: May 1, 1991
Creator: Robinson, A.L. & Schlachter, A.S.
Partner: UNT Libraries Government Documents Department
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Bias factors for radiation creep, growth and swelling

Description: Central to the present concepts of the origin of the radiation-induced creep, growth and swelling phenomena is the relative interaction of interstitials and vacancies with various sinks. Radiation-induced climb of dislocations, which figures in many theories of radiation creep and growth, requires the absorption of an excess of either vacancies or interstitials. On the other hand, radiation swelling requires the absorption of an excess of vacancies to affect void growth. These relative preferences are normally expressed in theoretical models by certain bias factors, or capture efficiencies, usually assumed to be constant. Several attempts have been made to estimate their magnitude theoretically but all are seen to involve errors or physically unrealistic assumptions. We present here a unified treatment in which these various bias factors are estimated in a self-consistent model which incorporates, for the first time, all the essential physics, i.e., defect production, interactions of both vacancies and interstitials with sinks and the presence of two types of sinks. We present quantitative evaluations for the SIPA creep model and for radiation swelling, and compare with previous estimates of these phenomena.
Date: January 1, 1979
Creator: Nichols, F.A.
Partner: UNT Libraries Government Documents Department
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Multiplicity Distributions in νμp Interactions

Description: Multiplicity distributions of the hadrons produced in antineutrino proton interactions are presented. The data sample, which consists of 2025 charged-current events with antineutrino energy greater than 5 GeV, comes from exposures of the 15-foot hydrogen bubble chamber to the broad-band antineutrino beam at Fermilab. The distribution in hadronic mass W has an average value of 3.7 GeV but extends up to 10 GeV. The mean multiplicity of charged hadrons depends on the hadronic mass W and varies as <n/sub ch/> = (-0.44 +- 0.13) + (1.48 +- 0.06) 1n W/sup 2/ for W/sup 2/ > 4 GeV/sup 2/. The mean multiplicities for events with three or more charged tracks averaged over the total data sample are <n/sub -/> = 1.68 +-0.03 and <n/sub 0/> = 1.11 +- 0.07 for ..pi../sup -/ and ..pi../sup 0/ production, respectively. The mean ..pi../sup 0/ multiplicity is found to increase slowly with n/sub -/. The integrated correlation coefficient f/sub 2//sup - -/ and the dispersion D/sup -/ are given as a function of n/sub -/. When compared to the distributions characteristic of other leptonic and hadronic reactions, a similarity is found between the anti ..nu..- data and results from hadronic reactions that have no diffractive component. Multiplicity data for the heavier particles K/sup 0/, rho and ..lambda.. are also summarized. The pion multiplicities in the current fragmentation region exceed those for the target fragmentation at all W values. They also satisfy the isospin relation 2<n/sub 0/> = <n/sub +/> + <n/sub -/> required for the fragmentation of an I = 1/2 quark when a W > 4 GeV selection is imposed.
Date: January 1, 1981
Creator: Derrick, M.; Gregory, P. & LoPinto, F.
Partner: UNT Libraries Government Documents Department
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Brayton-Cycle Heat Recovery System Characterization Program. Glass-furnace facility test plan

Description: The test plan for development of a system to recover waste heat and produce electricity and preheated combustion air from the exhaust gases of an industrial glass furnace is described. The approach is to use a subatmospheric turbocompressor in a Brayton-cycle system. The operational furnace test requirements, the operational furnace environment, and the facility design approach are discussed. (MCW)
Date: August 29, 1980
Partner: UNT Libraries Government Documents Department
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The Federal Reporter. Volume 72 Cases Argued and Determined in the Circuit Courts of Appeals and Circuit and District Courts of the United States. March-May, 1896.

Description: The Federal Reporter contains the text of decisions and commentary regarding cases tried in circuit and district courts throughout the United States. The opinions printed in the volumes include both written statements and oral comments transcribed for publication. Index of cases starts on page vii.
Date: 1896
Partner: UNT Libraries Government Documents Department
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Technology assessment of geothermal energy resource development

Description: Geothermal state-of-the-art is described including geothermal resources, technology, and institutional, legal, and environmental considerations. The way geothermal energy may evolve in the United States is described; a series of plausible scenarios and the factors and policies which control the rate of growth of the resource are presented. The potential primary and higher order impacts of geothermal energy are explored, including effects on the economy and society, cities and dwellings, environmental, and on institutions affected by it. Numerical and methodological detail is included in appendices. (MHR)
Date: April 15, 1975
Partner: UNT Libraries Government Documents Department
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Negative-hydrogen-ion sources

Description: There are two main areas of negative hydrogen ion applications: injection into high energy accelerators and production of beams of energetic hydrogen atoms for fusion devices. In both cases, the ease with which the charge state of negative ions can be changed by either single or double electron stripping is the reason that made their application attractive. In tandem accelerators, the final energy of H/sup +/ ions is twice as high as it would correspond to the terminal voltage, in circular accelerators (synchrotrons, storage rings) injection of H/sup +/ ions by full stripping of H/sup -/ ions in a foil inside the ring is not limited by the Liouville's theorem and results in a higher phase space density than achieved by direct H/sup +/ injection. Finally, beams of hydrogen atoms at energies above 100 keV, which will be required for plasma heating and current drive in future fusion devices, can efficiently be produced only by acceleration of negative ions and their subsequent neutralization.
Date: January 1, 1983
Creator: Prelec, K.
Partner: UNT Libraries Government Documents Department
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Friction in nuclear dynamics

Description: The problem of dissipation in nuclear dynamics is related to the breaking down of nuclear symmetries and the transition from ordered to chaotic nucleonic motions. In the two extreme idealizations of the perfectly Ordered Regime and the fully Chaotic Regime, the nucleus should behave as an elastic solid or an overdamped fluid, respectively. In the intermediate regime a complicated visco-elastic behaviour is expected. The discussion is illustrated by a simple estimate of the frequency of the giant quadrupole resonance in the Ordered Regime and by applications of the wall and window dissipation formulae in the Chaotic Regime. 51 refs.
Date: March 1, 1985
Creator: Swiatecki, W.J.
Partner: UNT Libraries Government Documents Department
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Ion confinement and radiation losses in the Advanced Toroidal Facility

Description: Collapses of stored energy are typically observed in low-density ({anti n}{sub e} {approx} 10{sup 13} cm{sup {minus}3}) extensively gettered ATF plasmas when the electron density rises to the ECH cutoff point, and the central heating is supplied only by neutral- beam-injection (NBI). However, the decline of stored energy can be avoided if the density is raised rapidly to about 5 {times} 10{sup 13} cm{sup {minus}3}. Three mechanisms have been proposed to explain the collapses: (1) impurity radiation, (2) excitation of an electron instability driven by the neutral beams, or (3) poor coupling of the beam ions to the thermal plasmas. Detailed spectroscopic studies of plasma cleanliness as a function of the gettering procedure have shown that radiation is an unlikely candidate for initiating collapses, although it may become an important loss mechanism once the electron temperature has fallen to a low level. No specific electron instability has yet been identified with injection, but recent experimental and computational work indicates that losses by shinethrough and charge exchange strongly influence the evolution of low-density plasmas. This report discusses the beam particle losses, thermal ions, and the evolution of radiation profiles.
Date: January 1, 1991
Creator: Isler, R. C.; Colchin, R. J.; Wade, M. R.; Lyon, J. F.; Fowler, R. H.; Rome, J. A. et al.
Partner: UNT Libraries Government Documents Department
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TMX-Upgrade neutral-beam injection system

Description: The TMX experiment proved that axial confinement of central-cell ions is improved ninefold by the electrostatic potential of end-cell plasmas. The TMX Upgrade task is to improve this confinement further. This paper discusses the injector system aspects of the TMX Upgrade.
Date: October 5, 1981
Creator: Felker, B.; Kane, R. J.; Wong, R. L.; Calderon, M. O. & Moore, T. L.
Partner: UNT Libraries Government Documents Department
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Martensitic phase transformation in shape-memory alloys

Description: Isothermal studies are described of the shape-recovery phenomenon, stress-strain behavior, electrical resistivity and thermo-electric power associated with the martensite-parent phase reaction in the Ni-Ti shape-memory alloys. The energy-balance equation that links the reaction kinetics with the strain energy change during the cooling-deforming and heating cycle is analyzed. The strain range in which the Clausius-Clapeyron equation satisfactorily describes this reaction is determined. A large change in the Young&#x27;s modulus of the specimen is found to be associated with the M ..--&gt;.. P reaction. A hysteresis loop in the resistivity-temperature plot is found and related to the anomaly in the athermal resistivity changes during cyclic M ..--&gt;.. P ..--&gt;.. M transformation. An explanation for the resistivity anomaly is offered. The M structure is found to be electrically negative relative to the P structure. A thermal emf of greater than or equal to 0.12 mV is found at the M-P interface.
Date: January 1, 1979
Creator: Golestaneh, A A
Partner: UNT Libraries Government Documents Department
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Mixing angles in SU(2)/sub L/ x U(1) gauge model

Description: Exact expressions for the mixing parameters are obtained in terms of mass ratios in the standard Weinberg-Salam model with permutation symmetry S/sub 3/ for six quarks. The CP-violating phase is ignored, and there are no arbitrary parameters except for the quark masses. In the lowest order, the angles defined by Kobayashi-Maskawa are sin theta/sub 1/ = sin theta/sub c/ = (m/sub d//m/sub d/ + m/sub s/)/sup 1/2/, sin theta/sub 3/ = -sin theta/sub 3/ = -m/sup 2//sub s//m/sup 2//sub b/, and m/sub t/m/sub s/ greater than or equal to m/sub c/m/sub b/ = 7.2 GeV/sup 2/ or m/sub t/ greater than or equal to 24 GeV for m/sub s/ = 0.3 GeV.
Date: January 1, 1979
Creator: Nandi, S. & Tanaka, K.
Partner: UNT Libraries Government Documents Department
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Spatial dependence of flux and damage in the FMIT test cell

Description: Experimental Li(d,n) thick target yields have been combined with nuclear models to determine the microscopic Li(d,n) cross section as a function of incoming deuteron energy (E/sub d/ < 40 MeV), of outgoing neutron energy (0 less than or equal to E/sub n/ less than or equal to 50 MeV), and of outgoing neutron angle (0 less than or equal to theta less than or equal to 180/sup 0/). A generalized least squares adjustment procedure using all the experimental data for 14 less than or equal to E/sub d/ less than or equal to 50 provided the overall normalization and the angular distribution, while the Serber stripping model and the evaporation model provided the neutron energy dependence. The cross sections are applied to the conditions appropriate to the FMIT (Fusion Materials Irradiation Testing) facility to determine flux and damage parameter levels inside the test cell.
Date: January 1, 1979
Creator: Mann, F. M.; Schmitroth, F.; Carter, L. L. & Schiffgens, J. O.
Partner: UNT Libraries Government Documents Department
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Report of the working group on data taking with bunched beams

Description: The purpose of this working group was to consider the problems created for experimenters under the bunched beam running conditions of ISABELLE Phase I. Some indication is given of the nature of the problem, the kinds of experiments that will have difficulties are identified, and some of the possibilities for dealing with them are considered.
Date: January 1, 1981
Creator: Blumenfeld, B.; Fernow, R. C.; Herrera, J. C.; Kabe, S.; Marx, M.; Nappi, A. et al.
Partner: UNT Libraries Government Documents Department
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Projections of automobile, light truck, and bus stocks and sales, to the year 2000

Description: Future stocks and sales of automobiles, light trucks, and buses are projected in this document. Automobile projections are developed for fleet and non-fleet sectors. Total auto stock is projected as a function of the number of households and of personal income, with adjustment for present and anticipated shifts from automobiles to light trucks. Automobile stocks and sales are projected to increase steadily through the year 2000 with a slightly larger growth rate associated with fleet autos. Projections of light-truck stocks and sales are developed for personal, service/utility, agriculture, manufacturing, government, wholesale/retail, and other uses based on anticipated employment and output for each of the use sectors. Projections anticipate the largest growth area to be that of personal light trucks. Bus stocks and sales are projected as a function of user populations, existing fleet characteristics, and anticipated usage patterns. School, intercity, and transit buses are included in the study. School buses are projected to have the largest percentage of growth in this sector.
Date: November 1, 1979
Creator: Knorr, R. & Millar, M.
Partner: UNT Libraries Government Documents Department
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