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Biological Conversion of Synthesis Gas. [Chlorobium Thiosulfatophilum, Chlorobium Phaeobacteroides, and Rhodospirillum Rubrum] (open access)

Biological Conversion of Synthesis Gas. [Chlorobium Thiosulfatophilum, Chlorobium Phaeobacteroides, and Rhodospirillum Rubrum]

The anaerobic bacterium Rhodospirillum rubrum has been chosen for catalysis of the biological water gas shift reaction. Two bacteria, Chlorobium thiosulfatophilum and Chlorobium phaeobacteroides, are being evaluated as candidates for H{sub 2}S conversion to elemental sulfur. Since these latter two organisms both grow and convert H{sub 2}S in batch culture using standard basal medium, the choice of a suitable bacterium must be made in consideration of specific growth and uptake rates. Produced elemental sulfur stability against further oxidation to sulfate, and minimal use of H{sub 2} as a producing agent must also be considered. The effects of temperature on the performance of R. rubrum were evaluated. It was found that the cell concentration was highest at temperatures of 25 and 30{degree}C, and that the specific uptake rate was highest at temperatures of 30, 32 and 34{degree}C. No growth was observed at 37{degree}C. Also, temperature did not affect the yield of H{sub 2} from CO. Thus, R. rubrum may be used for biological rates gas shift at any temperature between 30 and 34{degree}C, although growth is maximized at lower temperatures. Preliminary studies with C. thiosulfatophilum showed rapid utilization of H{sub 2}S from the gas and liquid phases with subsequent production of …
Date: January 6, 1992
Creator: unknown
System: The UNT Digital Library
Full-Scale Demonstration Low-NO sub x Cell trademark Burner retrofit (open access)

Full-Scale Demonstration Low-NO sub x Cell trademark Burner retrofit

The Low-NO{sub x} Cell{trademark} Burner operates on the principle of staged combustion. The lower burner of each two-nozzle cell is modified to accommodate all the fuel input previously handled by two nozzles. Secondary air, less than theoretically required for complete combustion, is introduced to the lower burner. The remainder of secondary air is directed to the upper port'' of each cell to complete the combustion process. B W/EPRI have thoroughly tested the LNCB{trademark} at two pilot scales (6 million Btu per hour and 100 million Btu per hour), and tested a single full-scale burner in a utility boiler. Combustion tests at two scales have confirmed NO{sub x} reduction with the low-NO{sub x} cell on the order of 50% relative to the standard cell burner at optimum operating conditions. The technology is now ready for full unit, full-scale demonstration.
Date: April 6, 1992
Creator: unknown
System: The UNT Digital Library
Measured leak rates of the temporary seals in DWPF canistered waste forms after three years of on site storage (open access)

Measured leak rates of the temporary seals in DWPF canistered waste forms after three years of on site storage

In the summer of 1990 a study was carried out to determine the-internal pressure, relative humidity, and chemical composition of the gas within the free volume of four canistered waste forms produced at TNX in May of 1988. Three of these canistered waste forms were sealed only by temporary seals and subsequently stored in the TNX boneyard' with no protection. The fourth canister was sealed by upset resistance welding. All three canisters with temporary seals were decontaminated by aqueous frit blasting. It was important to remeasure the leak rates of these seals to ensure that leaktightness had not deteriorated during canister handling and storage prior to the time the experiment were performed. This paper details the results of two separate measurements of the leak rates of these seals.
Date: April 6, 1992
Creator: Harbour, J. R. & Miller, T. J.
System: The UNT Digital Library
Steam gasification of carbon: Catalyst properties, March 15, 1992--June 14, 1992 (open access)

Steam gasification of carbon: Catalyst properties, March 15, 1992--June 14, 1992

This research uses several techniques to measure the concentration of catalyst sites and determine their stoichiometry for the catalyzed gasification of carbon. Both alkali and alkaline earth oxides are effective catalysts for accelerating the gasification rate of coal chars, but only a fraction of the catalyst appears to be in a form that is effective for gasification, and the composition of that catalyst is not established. Transient techniques, with {sup 13}C labeling, are being used to study the surface processes, to measure the concentration of active sites, and to determine the specific reaction rates. We have used secondary ion mass spectrometry (SIMS) for both high surface area samples of carbon/alkali carbonate mixtures and for model carbon surfaces with deposited alkali atoms. SIMS provides a direct measure of surface composition. The combination of these results can provide knowledge of catalyst dispersion and composition, and thus indicate the way to optimally utilize carbon gasification catalysts.
Date: July 6, 1992
Creator: Falconer, J. L.
System: The UNT Digital Library
Fusion, magnetic confinement (open access)

Fusion, magnetic confinement

An overview is presented of the principles of magnetic confinement of plasmas for the purpose of achieving controlled fusion conditions. Sec. 1 discusses the different nuclear fusion reactions which can be exploited in prospective fusion reactors and explains why special technologies need to be developed for the supply of tritium or {sup 3}He, the probable fuels. In Sec. 2 the Lawson condition, a criterion that is a measure of the quality of confinement relative to achieving fusion conditions, is explained. In Sec. 3 fluid equations are used to describe plasma confinement. Specific confinement configurations are considered. In Sec. 4 the orbits of particle sin magneti and electric fields are discussed. In Sec. 5 stability considerations are discussed. It is noted that confinement systems usually need to satisfy stability constraints imposed by ideal magnetohydrodynamic (MHD) theory. The paper culminates with a summary of experimental progress in magnetic confinement. Present experiments in tokamaks have reached the point that the conditions necessary to achieve fusion are being satisfied.
Date: August 6, 1992
Creator: Berk, H. L.
System: The UNT Digital Library
Toxicity testing results on increased supernate treatment rate of 3700 gallons/batch (open access)

Toxicity testing results on increased supernate treatment rate of 3700 gallons/batch

In July, 1991, Reactor Materials increased the supernate treatment concentration in the M-Area Dilute Effluent Treatment Facility from 2700 gallons of supernate per 36000 gallon dilute wastewater batch to 3700 gallons/batch. This report summarizes the toxicity testing on the effluents of the increased treatment rate.(JL)
Date: July 6, 1992
Creator: Pickett, J. B.; Martin, H. L. & Diener, G. A.
System: The UNT Digital Library
Criticality assessment of LLRWDF closure (open access)

Criticality assessment of LLRWDF closure

During the operation of the Low Level Radioactive Waste Disposal Facility (LLRWDF), large amounts (greater than 100 kg) of enriched uranium (EU) were buried. This EU came primarily from the closing and decontamination of the Naval Fuels Facility in the time period from 1987--1989. Waste Management Operations (WMO) procedures were used to keep the EU boxes separated to prevent possible criticality during normal operation. Closure of the LLRWDF is currently being planned, and waste stabilization by Dynamic Compaction (DC) is proposed. Dynamic compaction will crush the containers in the LLRWDF and result in changes in their geometry. Research of the LLRWDF operations and record keeping practices have shown that the EU contents of trenches are known, but details of the arrangement of the contents cannot be proven. Reviews of the trench contents, combined with analysis of potential critical configurations, revealed that some portions of the LLRWDF can be expected to be free of criticality concerns while other sections have credible probabilities for the assembly of a critical mass, even in the uncompacted configuration. This will have an impact on the closure options and which trenches can be compacted.
Date: October 6, 1992
Creator: Sarrack, A. G.; Weber, J. H. & Woody, N. D.
System: The UNT Digital Library
Toxicity testing results on increased supernate treatment rate of 3700 gallons/batch. Revision 1 (open access)

Toxicity testing results on increased supernate treatment rate of 3700 gallons/batch. Revision 1

In July, 1991, Reactor Materials increased the supernate treatment concentration in the M-Area Dilute Effluent Treatment Facility from 2700 gallons of supernate per 36000 gallon dilute wastewater batch to 3700 gallons/batch. This report summarizes the toxicity testing on the effluents of the increased treatment rate.(JL)
Date: July 6, 1992
Creator: Pickett, J. B.; Martin, H. L. & Diener, G. A.
System: The UNT Digital Library
[Multifractal Cloud Properties Data Assessment] (open access)

[Multifractal Cloud Properties Data Assessment]

Our group has been very active over the last year, analyzing a number of data sets to characterize multifractal cloud properties and assess the effects of clouds on surface radiation properties (spectral and broadband). The data sets analyzed include: AVHRR observations of clouds over the ocean, SPOT observations of clouds over the ocean, SSM/I observations of clouds over the ocean, pyranometer data with all-sky photographs, pyrgeometer data all-sky photographs, and spectral surface irradiance all-sky photographs. A number of radiative transfer computations have been performed to help in the interpretation of these observations or provide theoretical guidance for their analysis. Finally 4 number of radiative transfer models have been acquired and tested to prepare for the interpretation of ARM/CART data.
Date: May 6, 1992
Creator: Gautier, C.; Ricchiazzi, P.; Peterson, P.; Lavallee, D.; Frouin, R.; Lubin, D. et al.
System: The UNT Digital Library
Maximal CP Violation via Higgs-Boson Exchange (open access)

Maximal CP Violation via Higgs-Boson Exchange

The unitarity of the mixing matrix of the charged Higgs bosons, and the orthogonality of the mixing matrix of the neutral Higgs bosons, are used to derive upper bounds on the values of general CP-violating expressions. The bounds are independent of the total number of Higgs fields in any specific model. They allow is to relax the usual assumption of only one Higgs boson being light. It is natural that the CP violation in the exchange of neutral Higgs bosons between bottom quarks be particularly large.
Date: March 6, 1992
Creator: Lavoura, L.
System: The UNT Digital Library
Documentation of toxicity testing results on increased supernate treatment rate of 2700 gallons/batch. Revision 1 (open access)

Documentation of toxicity testing results on increased supernate treatment rate of 2700 gallons/batch. Revision 1

In February 1991, Reactor Materials increased the rate of supernate treatment in the M-Area Dilute Effluent Treatment Facility (DETF) from 1800 gallons to {approximately}2700 gallons of supernate per 36,000 gallon dilute wastewater batch. The first release of the treated effluent began on March 3, 1991. A series of whole effluent toxicity tests was conducted on the DETF effluent to determine if the increased supernate concentration would result in any chronic toxicity affects in the receiving stream (Tims Branch). The toxicity tests were conducted at instream concentrations equivalent to DETF release rates of 5, 10, 15, 20, and 25 gallons/min. The test results, based on 7-day Ceriodaphnia dubia chronic toxicity, indicated no toxicity effects at any concentration tested. Supernate treatment in DETF continued at the higher concentration.
Date: July 6, 1992
Creator: Pickett, J. B.
System: The UNT Digital Library
Monitoring conservative retrofits in single family buildings. Final technical report (open access)

Monitoring conservative retrofits in single family buildings. Final technical report

This study has provided detailed before-and-after information on the ambient and comfort conditions in nine single family buildings, and on the energy consumption of those buildings, for one or more energy conservation retrofits. The data were recorded in such a manner that as well as being able to determine the savings from the retrofits and the influence these retrofits have on the comfort conditions of the residence, the effects of the retrofits on time-of-day usage are also determinable. The following are included in appendices: a table of participant`s names, site addresses and retrofit; significant dates and appropriate comments; a day of data and an annotated data set; pre-retrofit and post-retrofit audit data sheets; and usage history.
Date: December 6, 1992
Creator: Richardson, C. S.
System: The UNT Digital Library
Measured leak rates of the temporary seals in DWPF canistered waste forms after three years of on site storage (open access)

Measured leak rates of the temporary seals in DWPF canistered waste forms after three years of on site storage

In the summer of 1990 a study was carried out to determine the-internal pressure, relative humidity, and chemical composition of the gas within the free volume of four canistered waste forms produced at TNX in May of 1988. Three of these canistered waste forms were sealed only by temporary seals and subsequently stored in the TNX `boneyard` with no protection. The fourth canister was sealed by upset resistance welding. All three canisters with temporary seals were decontaminated by aqueous frit blasting. It was important to remeasure the leak rates of these seals to ensure that leaktightness had not deteriorated during canister handling and storage prior to the time the experiment were performed. This paper details the results of two separate measurements of the leak rates of these seals.
Date: April 6, 1992
Creator: Harbour, J. R. & Miller, T. J.
System: The UNT Digital Library
Resistive Plate Chamber technology review (open access)

Resistive Plate Chamber technology review

A review of the resistive plate chamber technology option for the GEM muon system.
Date: October 6, 1992
Creator: Widgoff, M.; Alyea, E. D. & Ables, E.
System: The UNT Digital Library
Fusion, magnetic confinement (open access)

Fusion, magnetic confinement

An overview is presented of the principles of magnetic confinement of plasmas for the purpose of achieving controlled fusion conditions. Sec. 1 discusses the different nuclear fusion reactions which can be exploited in prospective fusion reactors and explains why special technologies need to be developed for the supply of tritium or {sup 3}He, the probable fuels. In Sec. 2 the Lawson condition, a criterion that is a measure of the quality of confinement relative to achieving fusion conditions, is explained. In Sec. 3 fluid equations are used to describe plasma confinement. Specific confinement configurations are considered. In Sec. 4 the orbits of particle sin magneti and electric fields are discussed. In Sec. 5 stability considerations are discussed. It is noted that confinement systems usually need to satisfy stability constraints imposed by ideal magnetohydrodynamic (MHD) theory. The paper culminates with a summary of experimental progress in magnetic confinement. Present experiments in tokamaks have reached the point that the conditions necessary to achieve fusion are being satisfied.
Date: August 6, 1992
Creator: Berk, H. L.
System: The UNT Digital Library
Confinement vessel analysis final report (open access)

Confinement vessel analysis final report

The overall purpose of the confinement vessel analysis program was to aid Los Alamos in validation of a new confinement vessel configuration. This was done in two steps: First, we developed a finite element analysis model of the benchmark confinement vessel and compared the results against test results to verify the accuracy of the model and analysis technique. We then changed the finite element model to represent the new confinement vessel configuration and predicted the response of the new vessel for specified loading conditions. This report describes the work done to achieve the objective.
Date: May 6, 1992
Creator: Lewis, B. B.
System: The UNT Digital Library
Steam gasification of carbon: Catalyst properties, March 15, 1992--June 14, 1992 (open access)

Steam gasification of carbon: Catalyst properties, March 15, 1992--June 14, 1992

This research uses several techniques to measure the concentration of catalyst sites and determine their stoichiometry for the catalyzed gasification of carbon. Both alkali and alkaline earth oxides are effective catalysts for accelerating the gasification rate of coal chars, but only a fraction of the catalyst appears to be in a form that is effective for gasification, and the composition of that catalyst is not established. Transient techniques, with {sup 13}C labeling, are being used to study the surface processes, to measure the concentration of active sites, and to determine the specific reaction rates. We have used secondary ion mass spectrometry (SIMS) for both high surface area samples of carbon/alkali carbonate mixtures and for model carbon surfaces with deposited alkali atoms. SIMS provides a direct measure of surface composition. The combination of these results can provide knowledge of catalyst dispersion and composition, and thus indicate the way to optimally utilize carbon gasification catalysts.
Date: July 6, 1992
Creator: Falconer, J. L.
System: The UNT Digital Library
Biological Conversion of Synthesis Gas. [Quarterly] Technical Report No. 2-1, September 5, 1991--December 4, 1991 (open access)

Biological Conversion of Synthesis Gas. [Quarterly] Technical Report No. 2-1, September 5, 1991--December 4, 1991

The anaerobic bacterium Rhodospirillum rubrum has been chosen for catalysis of the biological water gas shift reaction. Two bacteria, Chlorobium thiosulfatophilum and Chlorobium phaeobacteroides, are being evaluated as candidates for H{sub 2}S conversion to elemental sulfur. Since these latter two organisms both grow and convert H{sub 2}S in batch culture using standard basal medium, the choice of a suitable bacterium must be made in consideration of specific growth and uptake rates. Produced elemental sulfur stability against further oxidation to sulfate, and minimal use of H{sub 2} as a producing agent must also be considered. The effects of temperature on the performance of R. rubrum were evaluated. It was found that the cell concentration was highest at temperatures of 25 and 30{degree}C, and that the specific uptake rate was highest at temperatures of 30, 32 and 34{degree}C. No growth was observed at 37{degree}C. Also, temperature did not affect the yield of H{sub 2} from CO. Thus, R. rubrum may be used for biological rates gas shift at any temperature between 30 and 34{degree}C, although growth is maximized at lower temperatures. Preliminary studies with C. thiosulfatophilum showed rapid utilization of H{sub 2}S from the gas and liquid phases with subsequent production of …
Date: January 6, 1992
Creator: unknown
System: The UNT Digital Library
Full-Scale Demonstration Low-NO{sub x} Cell{trademark} Burner retrofit. Quarterly report No. 5, October 1, 1991--December 31, 1991 (open access)

Full-Scale Demonstration Low-NO{sub x} Cell{trademark} Burner retrofit. Quarterly report No. 5, October 1, 1991--December 31, 1991

The Low-NO{sub x} Cell{trademark} Burner operates on the principle of staged combustion. The lower burner of each two-nozzle cell is modified to accommodate all the fuel input previously handled by two nozzles. Secondary air, less than theoretically required for complete combustion, is introduced to the lower burner. The remainder of secondary air is directed to the upper ``port`` of each cell to complete the combustion process. B&W/EPRI have thoroughly tested the LNCB{trademark} at two pilot scales (6 million Btu per hour and 100 million Btu per hour), and tested a single full-scale burner in a utility boiler. Combustion tests at two scales have confirmed NO{sub x} reduction with the low-NO{sub x} cell on the order of 50% relative to the standard cell burner at optimum operating conditions. The technology is now ready for full unit, full-scale demonstration.
Date: April 6, 1992
Creator: unknown
System: The UNT Digital Library
The development of precipitated iron catalysts with improved stability. Technical progress report No. 5, September 16, 1988--December 16, 1988 (open access)

The development of precipitated iron catalysts with improved stability. Technical progress report No. 5, September 16, 1988--December 16, 1988

The objective of this program is to identify the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and to use these chemical principles in the design of catalysts suitable for slurry reactors. The performance targets are 88% CO+H{sub 2} conversion with less than 1% deactivation/day for 1 month and a methane and ethane selectivity of no more than 7% (based on hydrocarbons and oxygenates only) at a space velocity of at least 2 normal liters per hr per gram iron (NL/hr/gFe) using a synthesis gas with 0.5-1.0 H{sub 2}:CO ratio in a slurry reactor.
Date: May 6, 1992
Creator: Abrevaya, H.
System: The UNT Digital Library
The development of precipitated iron catalysts with improved stability. Technical progress report No. 10, December 16, 1989--April 31, 1990 (open access)

The development of precipitated iron catalysts with improved stability. Technical progress report No. 10, December 16, 1989--April 31, 1990

The objective of this program is to identify the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and to use these chemical principles in the design of catalysts suitable for slurry reactors. The performance targets are 88% CO+H{sub 2} conversion with less than 1% deactivation/day for 1 month and a methane and ethane selectivity of no more than 7% (based on hydrocarbons and oxygenates only) at a space velocity of at least 2 normal liters per hr gram iron (NL/hr/gFe) using a synthesis gas with 0.5--1.0 H{sub 2}:Co ratio in a slurry reactor.
Date: May 6, 1992
Creator: Abrevaya, H.
System: The UNT Digital Library
The development of precipitated iron catalysts with improved stability. Technical progress report No. 6, December 16, 1988--March 16, 1989 (open access)

The development of precipitated iron catalysts with improved stability. Technical progress report No. 6, December 16, 1988--March 16, 1989

The objective of this program is to identify the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and to use these chemical principles in the design of catalysts suitable for slurry reactors. The performance targets are 88% CO+H{sub 2} conversion with less than 1% deactivation/day for 1 month and a methane and ethane selectivity of no more than 7% (based on hydrocarbons and oxygenates only) at a space velocity of at least 2 normal liters per hr per gram iron (NL/hr/gFe) using a synthesis gas with 0.5-1.0 H{sub 2}:CO ratio in a slurry reactor.
Date: May 6, 1992
Creator: Abrevaya, H.
System: The UNT Digital Library
The Effect of Chemical Additives on the Synthesis of Ethanol. Final Technical Report, September 15, 1987--March 15, 1992 (open access)

The Effect of Chemical Additives on the Synthesis of Ethanol. Final Technical Report, September 15, 1987--March 15, 1992

The objective of this research was to investigate the reaction mechanism of higher alcohol and aldehyde synthesis from syngas and the role of additives in the synthesis. An in situ IR reaction system and probe molecule technique were developed to study adsorbed species, active sites, and reaction pathway during reaction. The catalysts used for this study included silica-supported Rh, Ru, and Ni. (VC)
Date: March 6, 1992
Creator: Chuang, S. S. C.
System: The UNT Digital Library
The development of precipitated iron catalysts with improved stability. Technical progress report No. 9, September 16, 1989--December 16, 1989 (open access)

The development of precipitated iron catalysts with improved stability. Technical progress report No. 9, September 16, 1989--December 16, 1989

The objective of this program is to identify the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and to use these chemical principles in the design of catalysts suitable for slurry reactors. The performance targets are 88% CO+H{sub 2} conversion with less than 1% deactivation/day for 1 month and a methane and ethane selectivity of no more than 7% (based on hydrocarbons and oxygenates only) at a space velocity of at least 2 normal liters per hr per gram iron (NL/hr/gFe) using a synthesis gas with 0.5-1.0 H{sub 2}:CO ratio in a slurry reactor.
Date: May 6, 1992
Creator: Abrevaya, H.
System: The UNT Digital Library