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Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

Description: The objective of this project is to provide the fundamental information on the mechanisms of bacterial leaching of pyrite. The knowledge of how bacterial leaching of pyrite functions is essential for design and development of a technology for coal cleaning with bacteria. The features of major electrochemical techniques will be examined to find out if any of them can provide a diagnostic information on the mechanisms of related reactions.
Date: January 1, 1992
Creator: Pesic, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: The fermentation pH has been observed to be the key parameter affecting the ratio of ethanol to acetate produced by Clostridium ljungdahlii. The effects of controlled pH on cell growth and product formation by C. ljungdahlii were measured. It was found that cell concentration and acetate concentration increased with pH, while the ethanol concentration was highest at the lower pH. The molar product ratio of ethanol to acetate was 0.74 at pH 4.0, 0.39 at pH 4.5 and 0.12 at pH 5.0. Future experime… more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: Research is continuing in an attempt to increase both the ethanol concentration and product ratio using C. ljungdahlii. The purpose of this report is to present data utilizing a medium prepared especially for C. ljungdahlii. Medium development studies are presented, as well as reactor studies with the new medium in batch reactors. CSTRs and CSTRs with cell recycle. The use of this new medium has resulted in significant improvements in cell concentration, ethanol concentration and product ratio.
Date: January 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Basic aspects of radiation action on microorganisms. Final report for the period ending October 31, 1977. [Radioresistance of micrococcus luteus]

Description: Progress is reported on studies on the basic aspects of radiation effects on microorganisms. Results are included from studies on the effects of uv pretreatment on the survival of ..gamma..-irradiated micrococcus luteus and uv-induced radioresistance to bacteriophage.
Date: December 1, 1977
Creator: Pollard, E.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of energy related activities on the plankton of the Chesapeake Bay. Section 1. Progress report, 1 August 1976--30 September 1977

Description: Progress is reported on a comprehensive study of the ecology of the Chesapeake Bay estuary system. Emphasis is placed on seasonal variations of initial energy fixation by phytoplankton primary producers and subsequent energy transfer to herbivours and becterial heterotrophs. The impact of chemical and radioactive effluents from electric power plants on the ecology of Chesapeake Bay will be assessed. Data are included on the role of plankton metabolism in regenerating nutrients, nutrient exchang… more
Date: 1977~
Creator: Taft, Jay L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Exploratory Research on Mutagenic Activity of Coal-Related Materials

Description: The following samples were found to be mutagenic for strains TA1538, TA98 and TA100 Salmonella typhimurium: ETTM-10, ETTM-11, ETTM-15, ETTM-16, and ETTM-17. ETTM-13 was marginally mutagenic for TA1537. ETTM-14 was slightly mutagenic for TA1537, TA1538, and TA98. Mutagenicity by all samples was demonstrated only in the presence of hepatic enzyme extracts (S9) which provided metabolic activation. ETTM-11 was shown to be the most mutagenic sample assayed thus far; specific activity was 2.79 x 10/s… more
Date: January 1, 1980
Creator: Warshawsky, D. & Schoeny, R. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Humic substance formation during wastewater infiltration

Description: Soil infiltration of wastewater effluents is a widely practiced method of treatment and disposal/reuse throughout the world. Renovation of the wastewater results from a wide variety of complex physicochemical and biological processes. One set of processes is speculated to involve the accumulation of organic matter by filtration and sorption followed by formation of humic substances. This humic substance formation can effect the performance of soil treatment systems by contributing to soil pore … more
Date: January 1, 1991
Creator: Siegrist, R.L. (Oak Ridge National Lab., TN (United States)); Hildmann-Smed, R.; Filip, Z.K. (Bundesgesundheitsamt (BGA), Langen (Germany). Inst. fuer Wasser-, Boden- und Lufthygiene) & Jenssen, P.D. (Norges Landbrukshoegskole, Aas (Norway). Centre for Soil and Environmental Research)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Photodegradation of mutagens in solvent-refined coal liquids

Description: The purpose of this investigation was to evaluate any changes in the chemical composition and microbial mutagenicities of two representative solvent-refined coal (SRC) liquids as a function of exposure time to sunlight and air. This information was desired to assess potential health hazards arising from ground spills of these liquids during production, transport and use. Results of microbial mutagenicity assays using Salmonella typhimurium TA98, conducted after exposure, showed that the mutagen… more
Date: April 1, 1984
Creator: Kalkwarf, D. R.; Stewart, D. L.; Pelroy, R. A. & Weimer, W. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Photoproduction of hydrogen by membranes of green photosynthetic bacteria

Description: Photoproduction of H/sub 2/ from ascorbate by unit-membrane vesicles from Chlorobium limicola f. thiosulfatophilum was achieved with a system containing gramicidin D, tetramethyl-p-phenylenediamine, methyl viologen, dithioerythritol, Clostridium hydrogenase, and an oxygen-scavenging mixture of glucose, glucose oxidase, ethanol, and catalase. Maximum quantum yield was less than one percent. Half maximum rate of H/sub 2/ production occurred at a white-light intensity of approximately 0.15 cm/sup … more
Date: January 1, 1980
Creator: Bernstein, J D & Olson, J M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Biological solutions to waste management

Description: The purpose of this program is to develop low-cost processes for the removal of toxic metals from geothermal residual brines. Processes and methodologies are also being developed for the utilization of detoxified residues. Laboratory work at Brookhaven National Laboratory (BNL) has shown that bioleaching is an efficient method for the removal of toxic metals from residual brine sludges. Samples of geothermal brine residues, supplied by the industry, containing elevated concentrations of heavy m… more
Date: January 1, 1988
Creator: Premuzic, E. T.; Lin, Mow & Kukacka, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, March 1, 1977--May 31, 1977

Description: The degradation of cellulosic biomass continues to focus on the anaerobic thermophile Clostridium thermocellum. When grown on crystalline cellulose (MN300) in batch culture, there is an initial rapid accumulation of reducing sugars but the sugars are rapidly metabolized in later times during the fermentation. When grown on Solka floc with periodic addition of the substrate, there is a continual accumulation of reducing sugars (xylose, glucose, and cellobiose) as well as ethanol and acetic acid … more
Date: June 1, 1977
Creator: Wang, D. I. C.; Cooney, C. L.; Demain, A. L.; Gomez, R. F. & Sinskey, A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Size distribution of autotrophy and microheterotrophy in reservoirs: implications for foodweb structure

Description: Particle size is a primary determinant of resources available to consumers and of the efficiency of energy transfer through planktonic food chains. Dual radioisotopic labeling (with /sup 14/C-bicarbonate and /sup 3/H-acetate) and size fractionation of naturally-occurring phytoplankton-bacterioplankton assemblages were employed to examine the particle size distributions of planktonic autotrophy and microheterotrophy in four limnologically-dissimilar US reservoirs (Lake Mead, Arizona-Nevada, olig… more
Date: January 1, 1981
Creator: Kimmel, B. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: A batch kinetic study involving Clostridium lungdahlii in a mineral medium was carried out in order to provide baseline data for the effects of nutrients on product ratio and kinetics. The use of this minimal medium containing vitamins, minerals, select amino acids and salts showed both a lower maximum specific growth rate and a lower maximum specific uptake rate than found when using a complex medium supplemented with 0.01% yeast extract. At the same time, the product ratio was improved slight… more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Microbial uptake of uranium, cesium, and radium

Description: The ability of diverse microbial species to concentrate uranium, cesium, and radium was examined. Saccharomyces cerevisiae, Pseudomonas aeruginosa, and a mixed culture of denitrifying bacteria accumulated uranium to 10 to 15% of the dry cell weight. Only a fraction of the cells in a given population had visible uranium deposits in electron micrographs. While metabolism was not required for uranium uptake, mechanistic differences in the metal uptake process were indicated. Uranium accumulated sl… more
Date: January 1, 1980
Creator: Strandberg, G. W.; Shumate, S. E., II; Parrott, J. R., Jr. & McWhirter, D. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Distinction between the roles of O/sub 2/ and of O/sup -//sub 2/ in biological radiodamage

Description: The paper attempts to elucidate the roles of oxygen and superoxide radical in biological damage due to ionizing radiation. Specifically, the effect of gamma radiation on the survival of T4 bacteriophage and of E. coli B has been investigated. (ACR)
Date: January 1, 1978
Creator: Samuni, A.; Chevion, M.; Halpern, Y. S.; Ilan, Y. A. & Czapski, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The hemicellulases from the ethanologenic thermophile: Themoanaerobacter ethanolius

Description: Previously, we had only obtained extremely low xylanase activity in cultures of {ital Thermoanaerobacter ethanolicus} strain JW200, despite demonstrated xylan hydrolysis. We were not able to increase the enzyme activity or concentrate it in solution. Therefore, we decided to isolate new strains of thermophilic anaerobes with higher xylanase activity as a future source for cloning xylanases into {ital T. ethanolicus}. We now have organisms exhibiting 100-fold higher xylanase activity than JW200,… more
Date: May 1, 1991
Creator: Wiegel, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Molecular biological enhancement of coal biodesulfurization. [Rhodococcus]

Description: The objective of this project is to produce one or more microorganisms capable of removing the organic and inorganic sulfur in coal. The original specific technical objectives of the project were to: Clone and characterize the genes encoding the enzymes of the 4S'' pathway (sulfoxide/sulfone/sulfonate/sulfate) for release of organic sulfur from coal; Return multiple copies of genes to the original host to enhance the biodesulfurization activity of that organism; Transfer this pathway into a fas… more
Date: March 15, 1990
Creator: Litchfield, J. H.; Fry, I.; Wyza, R. E.; Palmer, D. T.; Zupancic, T. J. & Conkle, H. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Molecular biological enhancement of coal biodesulfurization. [Rhodococcus, thiobacillus]

Description: The objective of this project is to produce one or more microorganisms capable of removing the organic and inorganic sulfur in coal. The original specific technical objectives of the project were to: clone and characterize the genes encoding the enzymes of the 4S'' pathway (sulfoxide/sulfone/sulfonate/sulfate) for release of organic sulfur from coal; return multiple copies of genes to the original host to enhance the biodesulfurization activity of that organism; transfer this pathway into a fas… more
Date: June 14, 1990
Creator: Litchfield, J. H.; Fry, I.; Wyza, R. E.; Palmer, D. T.; Zupancic, T. J. & Conkle, H. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Innovative technology demonstrations

Description: Currently, several innovative technologies are being demonstrated at Tinker Air Force Base (TAFB) to address specific problems associated with remediating two contaminated test sites at the base. Cone penetrometer testing (CPT) is a form of testing that can rapidly characterize a site. This technology was selected to evaluate its applicability in the tight clay soils and consolidated sandstone sediments found at TAFB. Directionally drilled horizontal wells have been successfully installed at th… more
Date: April 1, 1992
Creator: Anderson, D.B.; Hartley, J.N. & Luttrell, S.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: Previous results have shown that the yeast extract concentration and the medium pH significantly affect the ratio of ethanol to acetate in the product stream when fermenting CO, CO{sub 2} and H{sub 2} in synthesis gas to products by Clostridium ljungdahlii. Further experimentation has demonstrated the impact of eliminating yeast extract from the medium (except for the slight quantity transferred with the inoculm), especially when coupled with low pH. An ethanol to acetate product ratio of 4.0 w… more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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