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Fundamental studies of fusion plasmas (open access)

Fundamental studies of fusion plasmas

The major portion of this program is devoted to critical ICH phenomena. The topics include edge physics, fast wave propagation, ICH induced high frequency instabilities, and a preliminary antenna design for Ignitor. This research was strongly coordinated with the world's experimental and design teams at JET, Culham, ORNL, and Ignitor. The results have been widely publicized at both general scientific meetings and topical workshops including the speciality workshop on ICRF design and physics sponsored by Lodestar in April 1992. The combination of theory, empirical modeling, and engineering design in this program makes this research particularly important for the design of future devices and for the understanding and performance projections of present tokamak devices. Additionally, the development of a diagnostic of runaway electrons on TEXT has proven particularly useful for the fundamental understanding of energetic electron confinement. This work has led to a better quantitative basis for quasilinear theory and the role of magnetic vs. electrostatic field fluctuations on electron transport. An APS invited talk was given on this subject and collaboration with PPPL personnel was also initiated. Ongoing research on these topics will continue for the remainder fo the contract period and the strong collaborations are expected to continue, enhancing …
Date: May 26, 1992
Creator: Aamodt, R. E.; Catto, P. J.; D'Ippolito, D. A.; Myra, J. R. & Russell, D. A.
System: The UNT Digital Library
[Bifurcations and Patterns in Nonlinear Dissifative Systems] (open access)

[Bifurcations and Patterns in Nonlinear Dissifative Systems]

This report discusses the following topics: Rayleigh-Benard convection with an imposed horizontal flow; Rayleigh-Benard convection in a gas under non-boussinesq conditions; electro- convection in a nematic liquid crystal; and Rayleigh-Benard convection in a nematic liquid crystal. (LSP)
Date: February 26, 1992
Creator: Ahlers, G. & Cannell, D. S.
System: The UNT Digital Library
Steady-state and transient modeling of tracer and nutrient distributions in the global ocean (open access)

Steady-state and transient modeling of tracer and nutrient distributions in the global ocean

The deep circulation model developed by Wright and Stocker has been used to represent the latitude-depth distributions of temperature, salinity, radiocarbon and color'' tracers in the Pacific, Atlantic and Indian Oceans. Restoring temperature and salinity to observed surface data the model shows a global thermohaline circulation where deep water is formed in the North Atlantic and in the Southern Ocean. A parameter study reveals that the high-latitude surface salinity determines the composition of deep water and its flow in the global ocean. Increasing Southern Ocean surface salinity by 0.4 ppt the circulation changes from a present-day mode where North Atlantic Deep Water is one where Antarctic Bottom Water is dominant. An inorganic carbon cycle with surface carbonate chemistry is included, and gas exchange is parameterized in terms of pCO{sub 2} differences. Pre- industrial conditions are achieved by adjusting the basin-mean alkalinity. A classical 2{times}CO{sub 2} experiment yields the intrinsic time scales for carbon uptake of the ocean; they agree with those obtained from simple box models or 3-dimensional ocean general circulation models. Using the estimated industrial anthropogenic input of CO{sub 2} into the atmosphere the model requires, consistent with other model studies, an additional carbon flux to match the observed …
Date: March 26, 1992
Creator: Stocker, T.F. & Broecker, W.S.
System: The UNT Digital Library
Nebraska residential propane survey, Winter 1991/92 (open access)

Nebraska residential propane survey, Winter 1991/92

This report summarizes information on propane prices for the October 1991/March 1992 heating season in Nebraska. From October through March participating propane distributors were contacted twice monthly by the Nebraska Energy Office to obtain their current residential (retail) prices of propane. This information was faxed to the US Department of Energy, Energy Information Administration (DOE/EIA) biweekly in report format as prepared by the PEDRO system.
Date: June 26, 1992
Creator: Kinyon, L.
System: The UNT Digital Library
Revised minimum nitrite concentration for ESP (open access)

Revised minimum nitrite concentration for ESP

Nitrite is to be used to inhibit pitting corrosion during Extended Sludge Processing (ESP) at the Savannah River Plant. The required nitrite concentrations are expressed as a function of the slurries' nitrate ion concentration and temperature. In the most dilute slurries, the nitrite inhibitor requirement is independent of the nitrate ion concentration and depends only on the temperature of the waste. The nitrate-independent concentration ensures that there is sufficient inhibitor, in sludge slurries whose nitrate has been depleted by radiolysis, to prevent pitting corrosion induced by other corrosive anions (e.g., sulfate and chloride). The threshold nitrate concentration at which the nitrite level is expressed as a function only of temperature is 0.02 M.
Date: October 26, 1992
Creator: Zapp, P.E.
System: The UNT Digital Library
Development of a stable cobalt-ruthenium Fischer-Tropsch catalyst (open access)

Development of a stable cobalt-ruthenium Fischer-Tropsch catalyst

The work performed in the program suggests that cobalt catalytic performance is a complex function of crystallite size, crystallite composition, and cobalt-support interaction. These properties are determined by the nature of support, the bimetallic component, the promoters, and the method of preparation. Results so far indicate that the lowest methane selectivity occurs on support No. 8, and the highest activity is obtained on support No. 10. Also, promoters 2 and 3 may help lower the formation of methane. These findings, along with the catalyst knowledge gained during Union Carbide's former contract AC22-84PC70028, will be used to develop a superior cobalt catalyst.
Date: August 26, 1992
Creator: Abrevaya, H.
System: The UNT Digital Library
Direct aromatization of methane. Quarterly technical progress report No. 3, April 1, 1993--June 30, 1993 (open access)

Direct aromatization of methane. Quarterly technical progress report No. 3, April 1, 1993--June 30, 1993

Construction of quench-reactor has been completed. Gaseous reactants are fed in a downward flow and the quenching medium (water) pumped upward into a concentric reactor housed in a high temperature (1540C) furnace. The furnace has a 24 inch, resistively-heated zone, with an overall length of 38 inches. The gaseous effluent is sampled directly into a gas chromatograph via a sampling valve. The gas chromatographic procedure for analysis of expected products is being developed. Several columns have been tested for separating a standard mixture of C{sub 1} {minus} C{sub 9} aliphatic hydrocarbons and aromatics such as benzene, toluene, xylenes, ethylbenzene, and naphthalene. An Alumina-GS microbore capillary column had been found to provide the necessary separation, but with poor peak shape. Modification of injector system is planned and development of the analytical procedure is continuing. In anticipation of Task 4, in which catalysts will be employed to reduce the temperature of the pyrolysis, a preliminary search of the literature has identified several alumina-based materials that may be suitable for high temperature operation and will prove to have some catalytic activity. Preliminary synthesis and characterization of potentially useful materials have been started.
Date: September 26, 1992
Creator: unknown
System: The UNT Digital Library
Advanced liquefaction using coal swelling and catalyst dispersion techniques. Quarterly technical progress report, April--June 1992 (open access)

Advanced liquefaction using coal swelling and catalyst dispersion techniques. Quarterly technical progress report, April--June 1992

Research in this project centers upon developing a new approach to the direct liquefaction of coal to produce an all-distillate product slate at a sizable cost reduction over current technology. The approach integrates all aspects of the coal liquefaction process including coal selection, pretreatment, coal swelling with catalyst impregnation, coal liquefaction experimentation, product recovery with characterization, alternate bottoms processing, and a technical assessment including an economic evaluation. The project is being carried out under contract to the United States Department of Energy. On May 28, 1992, the Department of Energy authorized starting the experimental aspects of this projects; therefore, experimentation at Amoco started late in this quarterly report period. Research contracts with Auburn University, Pennsylvania State University, and Foster Wheeler Development Corporation were signed during June, 1992, so their work was just getting underway. Their work will be summarized in future quarterly reports. A set of coal samples were sent to Hazen Research for beneficiation. The samples were received and have been analyzed. The literature search covering coal swelling has been up-dated, and preliminary coal swelling experiments were carried out. Further swelling experimentation is underway. An up-date of the literature on the liquefaction of coal using dispersed catalysts is nearing …
Date: August 26, 1992
Creator: Curtis, C. W.; Gutterman, C. & Chander, S.
System: The UNT Digital Library
Steady-state and transient modeling of tracer and nutrient distributions in the global ocean. Progress report, June 1, 1991--March 31, 1992 (open access)

Steady-state and transient modeling of tracer and nutrient distributions in the global ocean. Progress report, June 1, 1991--March 31, 1992

The deep circulation model developed by Wright and Stocker has been used to represent the latitude-depth distributions of temperature, salinity, radiocarbon and ``color`` tracers in the Pacific, Atlantic and Indian Oceans. Restoring temperature and salinity to observed surface data the model shows a global thermohaline circulation where deep water is formed in the North Atlantic and in the Southern Ocean. A parameter study reveals that the high-latitude surface salinity determines the composition of deep water and its flow in the global ocean. Increasing Southern Ocean surface salinity by 0.4 ppt the circulation changes from a present-day mode where North Atlantic Deep Water is one where Antarctic Bottom Water is dominant. An inorganic carbon cycle with surface carbonate chemistry is included, and gas exchange is parameterized in terms of pCO{sub 2} differences. Pre- industrial conditions are achieved by adjusting the basin-mean alkalinity. A classical 2{times}CO{sub 2} experiment yields the intrinsic time scales for carbon uptake of the ocean; they agree with those obtained from simple box models or 3-dimensional ocean general circulation models. Using the estimated industrial anthropogenic input of CO{sub 2} into the atmosphere the model requires, consistent with other model studies, an additional carbon flux to match the observed …
Date: March 26, 1992
Creator: Stocker, T. F. & Broecker, W. S.
System: The UNT Digital Library
Predictions of a non-Gaussian model for large scale structure (open access)

Predictions of a non-Gaussian model for large scale structure

A modified CDM model for the origin of structure in the universe based on an inflation model with two interacting scalar fields, is analyzed to make predictions for the statistical properties of the density and velocity fields and the microwave background anisotropy. The initial gauge-invariant potential {zeta} which is defined as {zeta} = {delta}{rho}/({rho} + p) + 3{var_phi}, where {var_phi} is the curvature perturbation amplitude and p is the pressure, is the sum of a Gaussian field {phi}{sub 1}, and the square of a Gaussian field {phi}{sub 2}. A Harrison-Zel`dovich scale-invariant power spectrum is assumed for {phi}{sub 1}; and a log-normal `peak` power spectrum for {phi}{sub 2}. The location and the width of the peak are described by parameters k{sub c} and a. respectively. The model is motivated to some extent by inflation models with two interacting scalar fields, but is mainly interesting as an example of a model whose statistical properties change with scale. On small scales, it is almost identical to a standard scale-invariant Gaussian CDM model. On scales near the location of the peak of the non-Gaussian field, the distributions have long tails in high positive values of the density and velocity fields. Thus, it is easier …
Date: June 26, 1992
Creator: Fan, Z. H. & Bardeen, J. M.
System: The UNT Digital Library
Hydrogen generation in SRAT with nitric acid and late washing flowsheets (open access)

Hydrogen generation in SRAT with nitric acid and late washing flowsheets

Recently, SRTC recommended two process changes: (1) a final wash of the tetraphenylborate precipitate feed slurry and (2) the use of nitric acid to neutralize the sludge in the SRAT. The first change produced an aqueous hydrolysis product (PHA) with higher formic acid/formate and copper concentration, and reduced the nitrate content in the PHA by an order of magnitude. The second change is to substitute part of formic acid added to the SRAT with nitric acid, and therefore may reduce the hydrogen generated in the SRAT as well as provide nitrate as an oxidant to balance the redox state of the melter feed. The purpose of this report is to determine the pertinent variables that could affect the hydrogen generation rate with these process changes.
Date: October 26, 1992
Creator: Hsu, C. W.
System: The UNT Digital Library
[Bifurcations and Patterns in Nonlinear Dissifative Systems]. Progress Report (open access)

[Bifurcations and Patterns in Nonlinear Dissifative Systems]. Progress Report

This report discusses the following topics: Rayleigh-Benard convection with an imposed horizontal flow; Rayleigh-Benard convection in a gas under non-boussinesq conditions; electro- convection in a nematic liquid crystal; and Rayleigh-Benard convection in a nematic liquid crystal. (LSP)
Date: February 26, 1992
Creator: Ahlers, G. & Cannell, D. S.
System: The UNT Digital Library
Revised minimum nitrite concentration for ESP (open access)

Revised minimum nitrite concentration for ESP

Nitrite is to be used to inhibit pitting corrosion during Extended Sludge Processing (ESP) at the Savannah River Plant. The required nitrite concentrations are expressed as a function of the slurries` nitrate ion concentration and temperature. In the most dilute slurries, the nitrite inhibitor requirement is independent of the nitrate ion concentration and depends only on the temperature of the waste. The nitrate-independent concentration ensures that there is sufficient inhibitor, in sludge slurries whose nitrate has been depleted by radiolysis, to prevent pitting corrosion induced by other corrosive anions (e.g., sulfate and chloride). The threshold nitrate concentration at which the nitrite level is expressed as a function only of temperature is 0.02 M.
Date: October 26, 1992
Creator: Zapp, P. E.
System: The UNT Digital Library
Catalyst and process development for synthesis gas conversion to isobutylene. Quarterly report, January 1, 1992--March 31, 1992 (open access)

Catalyst and process development for synthesis gas conversion to isobutylene. Quarterly report, January 1, 1992--March 31, 1992

The objectives of this project are to develop a new catalyst, the kinetics for this catalyst, reactor models for trickle bed, slurry and fixed bed, and simulate the performance of fixed bed trickle flow reactors, slurry flow reactors, and fixed bed gas phase reactors for conversion of a hydrogen lean synthesis gas to isobutylene.
Date: May 26, 1992
Creator: Anthony, R. G. & Akgerman, A.
System: The UNT Digital Library
Analysis report for 241-BY-104 auger samples (open access)

Analysis report for 241-BY-104 auger samples

This document details the analytical sample results for two auger samples of the tip 15 cm (6 in.) of tank 241-BY-104 salt cake. The thermal response of tank 241-BY-104 auger samples is generally mild. The level of cyanide and iron, and therefore of ferrocyanide is very low. Evidence of inhomogeneity is present for tank 241-By-104 salt cake. Mass and charge balances were less than ideal. The concentrations found for the major constituents, except chromium, are in line with the expectations.
Date: October 26, 1992
Creator: Beck, M. A.; Bechtold, D. B. & Hey, B. E.
System: The UNT Digital Library
Chemistry of coal-related microparticles. Quarterly report, March 1, 1992--May 31, 1992 (open access)

Chemistry of coal-related microparticles. Quarterly report, March 1, 1992--May 31, 1992

This research project involves the study of coal macerals and sorbent microparticles used to remove S0{sub 2} and/or H{sub 2}S from process streams. To measure reaction rates a charged single microparticle will be held electrodynamically in one or more laser beams by superposed ac and dc electrical fields. The use of the electrodynamic balance for microparticle studies was pioneered by one of the principal investigators. One of the laser beams is used for light-scattering measurements to determine the particle size and to provide the excitation source for obtaining Raman spectra to chemically characterize the particle. The other beam, an infrared beam, is used to heat the particle electromagnetically. The first year of the research was devoted to preliminary experimental work and design studies. Although components and techniques must still be developed, experimental measurements on single macerals are now being done.
Date: May 26, 1992
Creator: Davis, J. E. & Krieger-Brockett, B.
System: The UNT Digital Library
ALT-II program progress report for FY92 (open access)

ALT-II program progress report for FY92

In FY92, the ALT-II program is concentrating on three main physics areas: pumped limiter experiments, which include He exhaust and high density high power operation; limiter bias experiments focused on modifying edge transport and particle removal; and and edge transport and flow studies, which examine the equilibrium edge flows and transport physics during Ohmic, L-mode, Supershot, and H-mode confinement regimes. In support of these physics objectives, a CCD diagnostic system has been delivered to TEXTOR and is being used to supplement the previous ALT-II diagnostic system. A second fast-scanning Langmuir probe was constructed at UCLA and has been delivered to TEXTOR for use in studies of edge plasma flows, turbulent transport, and poloidal asymmetries. A brief synopsis of each topic is given below. Work will continue on these physics topics during the balance of FY92.
Date: May 26, 1992
Creator: unknown
System: The UNT Digital Library
Ichthyoplankton entrainment study at the SRS Savannah River water intakes for Westinghouse Savannah River Company. Final report (open access)

Ichthyoplankton entrainment study at the SRS Savannah River water intakes for Westinghouse Savannah River Company. Final report

Cooling water for L and K Reactors and makeup water for Par Pond is pumped from the Savannah River at the 1G, 3G, and 5G pump houses. Ichthyoplankton (drifting fish larvae and eggs) from the river are entrained into the reactor cooling systems with the river water and passed through the reactor`s heat exchangers where temperatures may reach 70{degrees}C during full power operation. Ichthyoplankton mortality under such conditions is assumed to be 100 percent. The number of ichthyoplankton entrained into the cooling system depends on a variety of variables, including time of year, density and distribution of ichthyoplankton in the river, discharge levels in the river, and the volume of water withdrawn by the pumps. Entrainment at the 1 G pump house, which is immediately downstream from the confluence of Upper Three Runs Creek and the Savannah River, is also influenced by discharge rates and ichthyoplankton densities in Upper Three Runs Creek. Because of the anticipated restart of several SRS reactors and the growing concern surrounding striped bass and American shad stocks in the Savannah River, the Department of Energy requested that the Environmental Sciences Section (ESS) of the Savannah River Laboratory sample ichthyoplankton at the SRS Savannah River intakes. …
Date: March 26, 1992
Creator: Paller, M.
System: The UNT Digital Library
Ichthyoplankton entrainment study at the SRS Savannah River water intakes for Westinghouse Savannah River Company (open access)

Ichthyoplankton entrainment study at the SRS Savannah River water intakes for Westinghouse Savannah River Company

Cooling water for L and K Reactors and makeup water for Par Pond is pumped from the Savannah River at the 1G, 3G, and 5G pump houses. Ichthyoplankton (drifting fish larvae and eggs) from the river are entrained into the reactor cooling systems with the river water and passed through the reactor's heat exchangers where temperatures may reach 70[degrees]C during full power operation. Ichthyoplankton mortality under such conditions is assumed to be 100 percent. The number of ichthyoplankton entrained into the cooling system depends on a variety of variables, including time of year, density and distribution of ichthyoplankton in the river, discharge levels in the river, and the volume of water withdrawn by the pumps. Entrainment at the 1 G pump house, which is immediately downstream from the confluence of Upper Three Runs Creek and the Savannah River, is also influenced by discharge rates and ichthyoplankton densities in Upper Three Runs Creek. Because of the anticipated restart of several SRS reactors and the growing concern surrounding striped bass and American shad stocks in the Savannah River, the Department of Energy requested that the Environmental Sciences Section (ESS) of the Savannah River Laboratory sample ichthyoplankton at the SRS Savannah River intakes. …
Date: March 26, 1992
Creator: Paller, M. (Westinghouse Savannah River Co., Aiken, SC (United States))
System: The UNT Digital Library
Chemistry of coal-related microparticles (open access)

Chemistry of coal-related microparticles

This research project involves the study of coal macerals and sorbent microparticles used to remove S0{sub 2} and/or H{sub 2}S from process streams. To measure reaction rates a charged single microparticle will be held electrodynamically in one or more laser beams by superposed ac and dc electrical fields. The use of the electrodynamic balance for microparticle studies was pioneered by one of the principal investigators. One of the laser beams is used for light-scattering measurements to determine the particle size and to provide the excitation source for obtaining Raman spectra to chemically characterize the particle. The other beam, an infrared beam, is used to heat the particle electromagnetically. The first year of the research was devoted to preliminary experimental work and design studies. Although components and techniques must still be developed, experimental measurements on single macerals are now being done.
Date: May 26, 1992
Creator: Davis, J. E. & Krieger-Brockett, B.
System: The UNT Digital Library
Thermal Conductivity of Helium (open access)

Thermal Conductivity of Helium

This engineering note examines the thermal conductivity of helium as a function of temperature and pressure. The note attempts to determine the effect of varying pressure on the thermal conductivity of the vapor state over various temperature ranges. The plots clearly show that at temperatures above 20 degrees Kelvin. pressure does not have a significant effect on the thermal conductivity of Helium. In figures 1 and 2 the four isobaric curves are indistinguishable. This is also evident from the numeric data in table 1. Comparing the thermal conductivity of any particular row in table I, the thermal conductivity does not change by more than one percent from one column to another. Below 20K, the curves begin to diverge as they approach the saturation dome. This affect is more pronounced at pressures above the critical pressure of 0.23MPa, At which point the fluid is neither a liqUid or vapor. At pressures between atmospheriC pressure and 0.01 MPa, the thermal conductivity of Helium is independent of pressure below 20K as well as above 20K.
Date: August 26, 1992
Creator: Clark, D.
System: The UNT Digital Library
Parameterization of GCM Subgrid nonprecipitating cumulus and stratocumulus clouds using stochastic/phenomenological methods (open access)

Parameterization of GCM Subgrid nonprecipitating cumulus and stratocumulus clouds using stochastic/phenomenological methods

A theory was developed for the fraction of near-surface air likely to form forced and active cumulus clouds. This stochastic method is based on a 2-D frequency distribution of the occurrence of various buoyancy and condensation levels in air near the surface, and the relationship of this distribution to the mean temperature profile. An alternative form of this theory utilizes a 2-D distribution of convective available potential energies (CAPE) instead of virtual potential temperatures.
Date: August 26, 1992
Creator: Stull, R. B.
System: The UNT Digital Library
Fundamental studies of fusion plasmas. Annual performance report (open access)

Fundamental studies of fusion plasmas. Annual performance report

The major portion of this program is devoted to critical ICH phenomena. The topics include edge physics, fast wave propagation, ICH induced high frequency instabilities, and a preliminary antenna design for Ignitor. This research was strongly coordinated with the world`s experimental and design teams at JET, Culham, ORNL, and Ignitor. The results have been widely publicized at both general scientific meetings and topical workshops including the speciality workshop on ICRF design and physics sponsored by Lodestar in April 1992. The combination of theory, empirical modeling, and engineering design in this program makes this research particularly important for the design of future devices and for the understanding and performance projections of present tokamak devices. Additionally, the development of a diagnostic of runaway electrons on TEXT has proven particularly useful for the fundamental understanding of energetic electron confinement. This work has led to a better quantitative basis for quasilinear theory and the role of magnetic vs. electrostatic field fluctuations on electron transport. An APS invited talk was given on this subject and collaboration with PPPL personnel was also initiated. Ongoing research on these topics will continue for the remainder fo the contract period and the strong collaborations are expected to continue, enhancing …
Date: May 26, 1992
Creator: Aamodt, R. E.; Catto, P. J.; D`Ippolito, D. A.; Myra, J. R. & Russell, D. A.
System: The UNT Digital Library
[Fast neutron cross section measurements]. Progress report (open access)

[Fast neutron cross section measurements]. Progress report

From its inception, the Nuclear Data Project at the University of Michigan has concentrated on two major objectives: (1) to carry out carefully controlled nuclear measurements of the highest possible reliability in support of the national nuclear data program, and (2) to provide an educational opportunity for students with interests in experimental nuclear science. The project has undergone a successful transition from a primary dependence on our photoneutron laboratory to one in which our current research is entirely based on a unique pulsed 14 MeV fast neutron facility. The new experimental facility is unique in its ability to provide nanosecond bursts of 14 MeV neutrons under conditions that are ``clean`` and as scatter-free as possible, and is the only one of its type currently in operation in the United States. It has been designed and put into operation primarily by graduate students, and has met or exceeded all of its important initial performance goals. We have reached the point of its routine operation, and most of the data are now in hand that will serve as the basis for the first two doctoral dissertations to be written by participating graduate students. Our initial results on double differential neutron cross sections …
Date: October 26, 1992
Creator: Knoll, G. F.
System: The UNT Digital Library