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Assessment of research and development (R and D) needs in ammonia safety and environmental control

Description: This report characterizes the ammonia industry operations, reviews current knowledge of ammonia release and subsequent impacts, summarizes the status of release prevention and control methods and identify research and development needs for safety and environmental control. Appendices include: accidental spills and human exposure; adiabatic mixing of liquid nitrogen and air; fire and explosion hazards; and environmental impact rating tables. (PSB)
Date: September 1, 1981
Creator: Brenchley, D.L.; Athey, G.F. & Bomelburg, H.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Validation and sensitivity of a simulated photograph technique for visibility modeling

Description: The Los Alamos Scientific Laboratory (LASL) visibility model is capable of producing simulated before and after pictures that illustrate visual effects of smoke plumes. Although the model has been under development for a few years, until recently there had been very little testing of the model against field experience or testing of sensitivity of the model results to numerical approximations used in the model. Further validation and sensitivity testing of the LASL model began in late 1979. The … more
Date: January 1, 1980
Creator: Williams, M.; Chan, L.Y. & Lewis, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Use of principal components analysis and three-dimensional atmospheric-transport models for reactor-consequence evaluation

Description: This work explores the use of principal components analysis coupled to three-dimensional atmospheric transport and dispersion models for evaluating the environmental consequences of reactor accidents. This permits the inclusion of meteorological data from multiple sites and the effects of topography in the consequence evaluation; features not normally included in such analyses. The technique identifies prevailing regional wind patterns and their frequencies for use in the transport and dispersi… more
Date: January 1, 1982
Creator: Gudiksen, P. H.; Walton, J. J.; Alpert, D. J. & Johnson, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Diffusion of Slow Electrons in Gases

Description: The properties of electrons in a gas and an external electric field, e.g., agitation velocity, free path, energy lost per collision, and collision cross sections, were determined for electrons of energy less than 2 ev in a large number of gases. The computations were made from previously measured values for Townsend's energy factor or the ratio of electron agitation energy to molecule thermal energy. Results are presented for hydrogen, nitrogen, carbon dioxide, methane, ethylene, cyclopropane, … more
Date: October 24, 1961
Creator: Forester, D. W. & Cochran, L. W.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Studies of nuclear-waste migration in geologic media. Annual report, November 1976--October 1977

Description: The confinement of nuclear wastes in geologic formations is being considered as a method of permanently disposing of the waste. Laboratory experiments (column infiltration, static absorption, and batch partitioning experiments) were performed with nuclides of Cs, Pu, Np, and Am to examine the migratory characteristics of long-lived radionuclides that could be mobilized by groundwaters infiltrating a nuclear waste repository and the surrounding geologic body. In column infiltration experiments, … more
Date: March 1, 1978
Creator: Seitz, M.G.; Rickert, P.G.; Fried, S.M.; Friedman, A.M. & Steindler, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Enhanced tritium transport and release by solids modification

Description: To improve the tritium release characteristics of lithium ceramics, we are investigating the effects of dopants on tritium transport and release. Prior work has suggested a correlation between tritium and lithium diffusion in lithium-containing ceramics. This correlation has led us to propose a mechanism for tritium diffusion in which the tritium diffuses in the form of a lithium vacancy-triton complex. If this is the case, one should be able to increase the tritium diffusivity by increasing th… more
Date: January 1, 1989
Creator: Kopasz, J. P.; Tam, S. W. & Johnson, C. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Complex temporal and spatial patterns in nonequilibrium systems

Description: Dynamical systems methods are being developed and used to characterize the formation and evolution of temporal and spatial patterns in systems maintained far from equilibrium. In particular, experiments and analyses are considering electrodeposition of fractal metallic clusters, pattern formation in reaction-diffusion systems, and the primary instabilities of some fluid flows. Novel reactors have been developed to search for chemical patterns (spatial variations in the chemical composition), an… more
Date: September 1, 1991
Creator: Swinney, H. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of catalytic mineral matter on CO/CO sub 2 , temperature and burning time for char combustion

Description: The temperature of a char particle burning in an oxygen containing atmosphere is the product of a strongly coupled balance between particle size and physical properties, heat transfer from the particle, surface reactivity, CO/CO{sub 2} ratio and gas phase diffusion in the surrounding boundary layer and within the particle. CO{sub 2}/CO ratios can be strongly influenced by catalytic material in the carbon and by the char temperature. In this program we are measuring the CO{sub 2}/CO ratio for bo… more
Date: May 4, 1992
Creator: Longwell, J. P.; Sarofim, A. F.; Lee, Chun-Hyuk & Modestino, A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Review of Gaussian diffusion-deposition models

Description: The assumptions and predictions of several Gaussian diffusion-deposition models are compared. A simple correction to the Chamberlain source depletion model is shown to predict ground-level airborne concentrations and dry deposition fluxes in close agreement with the exact solution of Horst.
Date: January 1, 1979
Creator: Horst, T.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Transport, stability and relaxation of a spheromak

Description: We consider a zero-..beta.. spheromak contained in a rectangular region having perfectly conducting boundaries in its minimum energy state, and we calculate its evolution. Our results may be summarized as follows. Since this state is a stable equilibrium, the initial evolution of the plasma is caused by diffusion. We simulate this using a transport code. We find that q at the magnetic axis drops and q(r) becomes flat. When q on axis drops below 0.5, the spheromak becomes unstable to an n = 2 ki… more
Date: January 1, 1984
Creator: Sgro, A. G.; Marklin, G. & Mirin, A. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ion transport in stellarators

Description: Stellarator ion transport in the low-collisionality regime with a radial electric field is calculated by a systematic expansion of the drift-Boltzmann equation. The shape of the helical well is taken into account in this calculation. It is found that the barely trapped ions with three to four times the thermal energy give the dominant contribution to the diffusion. Expressions for the ion particle and energy fluxes are derived.
Date: September 1, 1985
Creator: Ho, D.D.M. & Kulsrud, R.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Separation of tritium from gaseous and aqueous effluent systems

Description: Three processes are discussed for separating tritium from gaseous and aqueous effluent systems: separation in the gas phase using Pd-25 wt percent Ag alloy diffusion membranes; electrolytic separation in the aqueous phase using ''bipolar'' electrodes; and the countercurrent exchange of tritium-containing hydrogen gas with water on catalytic surfaces combined with separation by direct electrolysis. (LK)
Date: January 1, 1977
Creator: Kobisk, E. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Transport and transfer rates in the waters of the continental shelf. Annual report

Description: The goal of govern project is to understand and quantify the processes that the transport and dispersal of energy-related pollutants introduced to the waters of the continental shelf and slope. The report is divided into sections dealing with processes associated with suspended solids; processes associated with sediments sinks for radionuclides and other pollutants; and spreading of water characteristics and species in solution. (ACR)
Date: September 1, 1980
Creator: Biscaye, P. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Prediction of the migration of several radionuclides in ocean sediment with the computer code IONMIG: a preliminary report

Description: A computer code, IONMIG, which is used to calculate the far-field transport of radionuclides through ocean sediment by diffusion and convection is described. The code uses a two-dimensional, axisymmetric, explicit finite difference formulation. Preliminary results for several species (Cs, Pu, I, Tc) are given.
Date: May 1, 1980
Creator: Russo, A.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The interaction of energetic alpha-particles with intense lower hybrid waves

Description: Lower hybrid waves are a demonstrated, continuous means of driving toroidal current in a tokamak. When these waves propagate in a tokamak fusion reactor, in which there are energetic {alpha}- particles, there are conditions under which the {alpha}-particles do not appreciably damp, and may even amplify, the wave, thereby enhancing the current-drive effect. Waves traveling in one poloidal direction, in addition to being directed in one toroidal direction, are shown to be the most efficient drive… more
Date: June 1, 1992
Creator: Fisch, N. J. & Rax, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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D. phi. vertex drift chamber construction and test results

Description: A jet-cell based vertex chamber has been built for the D{O} experiment at Fermilab and operated in a test beam there. Low drift velocity and diffusion properties were achieved using CO{sub 2}(95%)-ethane(5%) at atmospheric pressure. The drift velocity is found to be consistent with (9.74+8.68( E -1.25)) {mu}m/nsec where E is the electric field strength in (kV/cm < E z 1.6 kV/cm.) An intrinsic spatial resolution of 60 {mu}m or better for drift distances greater than 2 mm is measured. The track p… more
Date: May 1, 1991
Creator: Clark, A.R.; Goozen, F.; Grudberg, P.; Klopfenstein, C.; Kerth, L.T.; Loken, S.C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Revised Users Manual, Pulverized Coal Gasification or Combustion: 2-Dimensional (87-PCGC-2): Final Report, Volume 2. [87-PCGC-2]

Description: A two-dimensional, steady-state model for describing a variety of reactive and non-reactive flows, including pulverized coal combustion and gasification, is presented. Recent code revisions and additions are described. The model, referred to as 87-PCGC-2, is applicable to cylindrical axi-symmetric systems. Turbulence is accounted for in both the fluid mechanics equations and the combustion scheme. Radiation from gases, walls, and particles is taken into account using either a flux method or dis… more
Date: December 1, 1987
Creator: Smith, P. J.; Smoot, L. D. & Brewster, B. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calculation of particulate dispersion in a design-basis tornadic storm from the Atomics International Nuclear Material Development Facility, Santa Susana, California

Description: A three-dimensional numerical model is used to calculate ground-level air concentration and deposition (due to precipitation scavenging) after a hypothetical tornado strike at the Atomics International Nuclear Material Development Facility at Santa Susana, California. Plutonium particles less than 20 ..mu..m in diameter are assumed to be lifted into the tornadic storm cell by the vortex. The rotational characteristics of the tornadic storm are embedded within the larger mesoscale flow of the st… more
Date: July 1, 1980
Creator: Pepper, D.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermally Induced Structural Changes in Coal Combustion

Description: The effect of particle shape on char burnout is investigated in the limit of shrinking core combustion. As a first step, the particle temperature is assumed to proceed in the shrinking core regime and under conditions of negligible Stefan flow. The problem then reduces to calculating the oxygen concentration field around a non-spherical particle with the oxidation reaction taking place on the external surface. This problem has been addressed by an analytical technique and a numerical technique.… more
Date: January 17, 1990
Creator: Gavalas, G. R. & Flagan, R. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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