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Process development studies on the bioconversion of cellulose and production of ethanol

Description: Preliminary studies show minimal conversion of wood by sulfur dioxide at pressures of 38 psi at room temperature. Evaluation studies of Rut-C-30 and Rut-L-5 Trichoderma viride strains were compared. Studies on the continuous production system by manipulating temperature, pH, Tween 80 level substrate concentration, and dilution rate were performed. The known major components of cellulases were characterized. Studies on the reduction of the cost of producing sugar from corn stover were performed. Development of medium for continuous ethanol fermentation is discussed. Experiments show that the growth limiting factors for continuous fermentation were in the yeast extract. Biotin, pantothenic acid, and pyridoxine appear to be growth limiting factors. Addition of other vitamins had no effect on cell yield but increased ethanol production. The flash ferm process is discussed. Utilization of hemicellulose sugars is described. (DC)
Date: December 1, 1979
Creator: Wilke, C.R. & Blanch, H.W.
Partner: UNT Libraries Government Documents Department

Regional myocardial blood flow, metabolism and function assessed noninvasively by positron emission tomography

Description: Positron emission computed tomography is a new technique for the noninvasive measure of myocardial blood flow, mechanical function and, in particular, metabolism. The capability of this new study means is due to the technological innovations of the imaging device and the availability of radioactive tracers that are specific for blood flow and metabolism. The device permits recording of cross-sectional images of the left ventricular myocardium that reflect quantitatively regional tracer tissue concentrations. By employing tracer kinetic models this new technique permits the measurement of regional glucose and fatty acid metabolism of the heart. While already an important new tool for investigative studies into cardiac physiology and pathophysiology, the clinical utility of positron emission tomography remains to be defined.
Date: January 1, 1979
Creator: Schelbert, H.R.; Phelps, M.E.; Hoffman, E.; Huang, S. & Kuhl, D.E.
Partner: UNT Libraries Government Documents Department

Noninvasive measurement of regional myocardial glucose metabolism by positron emission computed tomography. [Dogs]

Description: While the results of regional myocardial glucose metabolism measurements using positron emission computed tomography (/sup 13/N-ammonia) are promising, their utility and value remains to be determined in man. If this technique can be applied to patients with acute myocardial ischemia or infarction it may permit delineation of regional myocardial segments with altered, yet still active metabolism. Further, it may become possible to evaluate the effects of interventions designed to salvage reversibly injured myocardium by this technique.
Date: June 1, 1980
Creator: Schelbert, H.R. & Phelps, M.E.
Partner: UNT Libraries Government Documents Department

Ethanol annual report FY 1990

Description: This report summarizes the research progress and accomplishments of the US Department of Energy (DOE) Ethanol from Biomass Program, field managed by the Solar Energy Research Institute, during FY 1990. The report includes an overview of the entire program and summaries of individual research projects. These projects are grouped into the following subject areas: technoeconomic analysis; pretreatment; cellulose conversion; xylose fermentation; and lignin conversion. Individual papers have been indexed separately for inclusion on the data base.
Date: January 1, 1991
Creator: Texeira, R.H. & Goodman, B.J. (eds.)
Partner: UNT Libraries Government Documents Department

Radiolytic gas production during long-term storage of nuclear wastes

Description: Gases produced by in situ radiolysis of sealed solidified nuclear wastes during long-term storage could conceivably breach containment. Therefore, candidate waste forms (matrices containing simulated nuclear wastes) were irradiated with /sup 60/Co-..gamma.. and /sup 244/Cm-..cap alpha.. radiation. These forms were: cement containing simulated fission product sludges, vermiculite containing organic liquids, and cellulosics contaminated with ..cap alpha..-emitting transuranic isotopes. For cement waste forms exposed to ..gamma..-radiolysis, an equilibrium hydrogen pressure was reached that was dose rate dependent. For ..cap alpha..-radiolysis, equilibrium was not reached. With organic wastes (n-octane on vermiculite), H/sub 2/ and traces of CO/sub 2/ and CH/sub 4/ were produced, and O/sub 2/ was consumed with both radiations. Only energy absorbed by the organic material was effective in producing H/sub 2/. At low dose rates with both ..cap alpha..- and ..gamma..-irradiations, G(H/sub 2/) was 4.5 and G(-O/sub 2/) was 5.0. Also, equilibrium was not obtained. For cellulosic material, H/sub 2/, CO/sub 2/, and CO were produced in the ratio of 1.0:0.7:0.3, and O/sub 2/ was consumed. With ..cap alpha..-radiolysis, G(gas) was dose dependent; measured values ranged from 2.2 to 0.6 as the dose increased. Implications of all these results on long-term storage of radioactive waste are discussed. Some data from an actual nuclear wasteform are also presented.
Date: January 1, 1976
Creator: Bibler, N. E.
Partner: UNT Libraries Government Documents Department

Non-labile tritium in Savannah River Plant pine trees

Description: Non-labile tritium bound in cellulose of pine trees was measured to learn about the effects and fate of tritium contributed to the environment by the Savannah River Plant (SRP). An estimation of the regional inventory and the distance tritium can be observed from SRP was desired because tritium is a major component of the radioactivity released by SRP, and as the oxide, it readily disperses in the environment. (auth)
Date: June 1, 1976
Creator: Sanders, S. M. Jr.
Partner: UNT Libraries Government Documents Department

Labeling cellular elements of blood with Technetium-99m

Description: The purpose of this proposal is to develop new technique of labeling platelets and white cells with Tc-99m radionuclide. The conditions of labeling canine platelets and white cells with the lipid-soluble Tc-99m HMPAO have been optimized. The function of labeled platelets were evaluated by the determination of platelet survival time and recovery and these values were compared with that of In-111 tropolone labeled platelets. We developed the bilateral femoral catheterization model for the evaluation of platelet-thrombosis on control and heparin-bonded catheters in dogs. We are evaluating platelet thrombosis in the hollow-fiber hemodialyzer with Tc-99m and In-111 labeled platelets. We have developed the flow-loop for in vitro studies and are using a pig model for quantitation of platelet-consumption during hemodialysis. We are currently evaluating the new technique of platelet and white cell-labeling with Tc-99m and testing them in animal models of thrombosis and infection (osteo-myelitis). We are also using the Tc-99m HMPAO labeled mixed white cells in the early diagnosis (3-hour post-injection) of acute and chronic infection in patients and comparing the results with that of IN-111 oxine labeled white cells.
Date: August 1, 1990
Creator: Dewanjee, M.K.
Partner: UNT Libraries Government Documents Department

Control of radioactive waste-glass melters

Description: Slurries of simulated high level radioactive waste and glass formers have been isothermally reacted and analyzed to identify the sequence of the major chemical reactions in waste vitrification, their effect on glass production rate, and the development of leach resistance. Melting rates of waste batches have been increased by the addition of reducing agents (formic acid, sucrose) and nitrates. The rate increases are attributable in part to exothermic reactions which occur at critical stages in the vitrification process. Nitrates must be balanced by adequate reducing agents to avoid the formation of persistent foam, which would destabilize the melting process. The effect of foaming on waste glass production rates is analyzed, and melt rate limitations defined for waste-glass melters, based upon measurable thermophysical properties. Minimum melter residence times required to homogenize glass and assure glass quality are much smaller than those used in current practice. Thus, melter size can be reduced without adversely affecting glass quality. Physical chemistry and localized heat transfer of the waste-glass melting process are examined, to refine the available models for predicting and assuring glass production rate. It is concluded that the size of replacement melters and future waste processing facilities can be significantly decreased if minimum heat transfer requirements for effective melting are met by mechanical agitation. A new class of waste glass melters has been designed, and proof of concept tests completed on simulated High Level Radioactive Waste slurry. Melt rates have exceeded 155 kg m{sup {minus}2} h{sup {minus}1} with slurry feeds (32 lb ft{sup {minus}2} h{sup {minus}1}), and 229 kg kg m{sup {minus}2} h{sup {minus}1} with dry feed (47 lb ft{sup {minus}2} h{sup {minus}1}). This is about 8 times the melt rate possible in conventional waste- glass melters of the same size. 39 refs., 5 figs., 9 tabs.
Date: January 1, 1990
Creator: Bickford, D.F. (Westinghouse Savannah River Co., Aiken, SC (USA)); Hrma, P. (Case Western Reserve Univ., Cleveland, OH (USA)) & Bowan, B.W. II (West Valley Nuclear Services Co., Inc., West Valley, NY (USA))
Partner: UNT Libraries Government Documents Department