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ENHANCED PRACTICAL PHOTOSYNTHETIC CO{sub 2} MITIGATION

Description: This quarterly report documents significant achievements in the Enhanced Practical Photosynthetic CO{sub 2} Mitigation project during the period from 1/2/2004 through 4/1/2004. Specific results and accomplishments for the first quarter of 2004 include: (1) CRF-2 test system: After the recent successful test results were achieved, the system was taken off-line for re-sealing and other operational improvements to prepare for the next level of testing, which will include direct measurement of carbon uptake in addition to organism mass measurements. (2) 15 biomass slurry samples are currently being analyzed with carbon dating techniques at Galbraith Labs, and statistical analysis of the results will determine if pre and post test carbon analysis is an acceptable means for carbon uptake estimation. (3) Pilot Scale: Quantitative organism growth testing is underway in the pilot scale bioreactor. Problems with uniformity of organism loading delayed the start of quantitative testing, and it remains as a continuing issue that has not been completely resolved. (4) The sustainability test was begun with approximately 30 gallons of algae and 2 Omnisil membranes. The initial mass determination procedure was completed, and the biomass growth over the course of the experiment has been preliminarily quantified.
Date: April 15, 2004
Creator: Kremer, Gregory; Bayless, David J.; Vis, Morgan; Prudich, Michael; Cooksey, Keith & Muhs, Jeff
Partner: UNT Libraries Government Documents Department

Application of joint inversion for mapping fluid parameters

Description: A two-dimensional joint inversion technique, based on a least-squares criterion of the data misfit and model smoothness, has been developed using electromagnetic (EM) and seismic traveltime data to assess the feasibility of directly inverting for hydrological parameters, such as fluid electrical conductivity, porosity, and saturation. This is accomplished by relating hydrological parameters to geophysical properties with the help of the empirical Archie's law and the Wyllie time average equation. While the latter links the underground seismic wave velocity and subsurface media porosity, the former relates the bulk formation conductivity to hydrological parameters such as fluid conductivity and porosity. Direct joint inversion using various geophysical data also reduces the non-uniqueness of the problem since common parameters are involved, as is the porosity related to both seismic traveltime and magnetic field. This newly developed joint inversion algorithm has been applied to a set of crosshole seismic and EM field data provided by Chevron as part of the Lost Hills CO{sub 2} pilot project in Southern California. Both EM and seismic pre- and post-injection data were evaluated in terms of hydrological parameters using general empirical relationships derived from logging data. The results show that the injection has decreased the water saturation and bulk conductivity in the whole inter-well section. Layered structure in the region is clearly displayed and major changes in water saturation and bulk conductivity are also observed.
Date: September 13, 2002
Creator: Tseng, Hung-Wen & Lee, Ki Ha
Partner: UNT Libraries Government Documents Department

Testing of CoTreat Inorganic Ion Exchange Media for the Removal of 60Co from Thorp Pond Water

Description: CoTreat, a new inorganic ion exchange media, has been studied in the laboratory to support its application as a pre- coat to existing Funda filters in THORP feed pond plant (Sellafield, UK). This is a novel way of application of CoTreat, which is usually utilized in fixed-bed ion exchange columns in a granular form. The results present the effect of operating conditions (CoTreat dose, pond water chemistry) on CoTreat performance for the removal of Co-57 tracer from simulated pond water. Major findings include the strong dependence of Co-57 decontamination factor (DF) on feed activity. At the 200 Bq/L feed level, the observed DF was 10-20 but rose to 1000 and above when the feed level was increased to 20000 Bq/L. Calcium present in the feed was found to decrease the DF at concentrations higher than 1 ppm. The laboratory studies showed significantly higher DF's than what has been observed in large-scale THORP tests. This discrepancy is likely to be due to the technique used in applying the Co Treat layer to the Thorp HEFP Funda filter. Options for improving Co Treat performance (i.e. application technique) under Funda filter operating conditions are being investigated by BNFL based on this laboratory work.
Date: February 25, 2003
Creator: Harjula, R.; Paajanen, A.; Lehto, J.; Tusa, E. & Strandring, P.
Partner: UNT Libraries Government Documents Department

BNL NONLINEAR PRE TEST SEISMIC ANALYSIS FOR THE NUPEC ULTIMATE STRENGTH PIPING TEST PROGRAM.

Description: The Nuclear Power Engineering Corporation (NUPEC) of Japan has been conducting a multi-year research program to investigate the behavior of nuclear power plant piping systems under large seismic loads. The objectives of the program are: to develop a better understanding of the elasto-plastic response and ultimate strength of nuclear piping; to ascertain the seismic safety margin of current piping design codes; and to assess new piping code allowable stress rules. Under this program, NUPEC has performed a large-scale seismic proving test of a representative nuclear power plant piping system. In support of the proving test, a series of materials tests, static and dynamic piping component tests, and seismic tests of simplified piping systems have also been performed. As part of collaborative efforts between the United States and Japan on seismic issues, the US Nuclear Regulatory Commission (USNRC) and its contractor, the Brookhaven National Laboratory (BNL), are participating in this research program by performing pre-test and post-test analyses, and by evaluating the significance of the program results with regard to safety margins. This paper describes BNL's pre-test analysis to predict the elasto-plastic response for one of NUPEC's simplified piping system seismic tests. The capability to simulate the anticipated ratcheting response of the system was of particular interest. Analyses were performed using classical bilinear and multilinear kinematic hardening models as well as a nonlinear kinematic hardening model. Comparisons of analysis results for each plasticity model against test results for a static cycling elbow component test and for a simplified piping system seismic test are presented in the paper.
Date: August 17, 2003
Creator: DEGRASSI,G.; HOFMAYER,C.; MURPHY,C.; SUZUKI,K. & NAMITA,Y.
Partner: UNT Libraries Government Documents Department

CO2 CAPTURE PROJECT - AN INTEGRATED, COLLABORATIVE TECHNOLOGY DEVELOPMENT PROJECT FOR NEXT GENERATION CO2 SEPARATION, CAPTURE AND GEOLOGIC SEQUESTRATION

Description: The CO{sub 2} Capture Project (CCP) is a joint industry project, funded by eight energy companies (BP, ChevronTexaco, EnCana, Eni, Norsk Hydro, Shell, Statoil, and Suncor) and three government agencies (1) European Union (DG Res & DG Tren), (2) Norway (Klimatek) and (3) the U.S.A. (Department of Energy). The project objective is to develop new technologies, which could reduce the cost of CO{sub 2} capture and geologic storage by 50% for retrofit to existing plants and 75% for new-build plants. Technologies are to be developed to ''proof of concept'' stage by the end of 2003. The project budget is approximately $24 million over 3 years and the work program is divided into eight major activity areas: (1) Baseline Design and Cost Estimation--defined the uncontrolled emissions from each facility and estimate the cost of abatement in $/tonne CO{sub 2}. (2) Capture Technology, Post Combustion: technologies, which can remove CO{sub 2} from exhaust gases after combustion. (3) Capture Technology, Oxyfuel: where oxygen is separated from the air and then burned with hydrocarbons to produce an exhaust with high CO{sub 2} for storage. (4) Capture Technology, Pre -Combustion: in which, natural gas and petroleum coke are converted to hydrogen and CO{sub 2} in a reformer/gasifier. (5) Common Economic Model/Technology Screening: analysis and evaluation of each technology applied to the scenarios to provide meaningful and consistent comparison. (6) New Technology Cost Estimation: on a consistent basis with the baseline above, to demonstrate cost reductions. (7) Geologic Storage, Monitoring and Verification (SMV): providing assurance that CO{sub 2} can be safely stored in geologic formations over the long term. (8) Non-Technical: project management, communication of results and a review of current policies and incentives governing CO{sub 2} capture and storage. Technology development work dominated the past six months of the project. Numerous studies are making substantial ...
Date: August 1, 2003
Creator: Kerr, Dr. Helen
Partner: UNT Libraries Government Documents Department

Relevance of photobiological repair

Description: From symposium on new trends in photobiology; Rio de Janeiro, Brazil (15 Jul 1973). A review is presented of photobiological and photochemical studies in relation to radiation damage and repair. Some topics discussed are: repair of damage induced in DNA by ultraviolet and gamma radiation; the repair of chemically induced damage to DNA; uv-induced skin cancer; enzymic photoreactivation of uv-irradiated DNA; and phoioreactivation of uv-induced tumors in fish. (HLW)
Date: January 1, 1973
Creator: Setlow, R.B.
Partner: UNT Libraries Government Documents Department

Repair of ultraviolet-light-induced damage

Description: Studies are reviewed which present three major new findings in the photobiology of skin. First, detectable numbers of dimers are formed even at sub-erythymal doses. Second, excision of dimers is much more rapid than would be predicted from results obtained in cell culture. Third, comparison of the rates of excision and photoreactivation in skin indicates that in normal sunlight exposure, photoreactivation may well be the predominant repair pathway in skin. (ACR)
Date: January 1, 1981
Creator: Sutherland, B.M.
Partner: UNT Libraries Government Documents Department

Damages to DNA that result in neoplastic transformation

Description: Some topics discussed are: correlation between carcinogens and mutagens; defective DNA repair in uv-damaged xeroderma pigmentosum cells; analysis of nucleotide damage to DNA following exposure to chemicals or radiations; photoreactivation in uv-irradiated Escherichia coli; tumor development in fish; excision repair as an aid in identifying damage; detection of excision repair; role of endonucleases in repair of uv damage; and alkylation products and tumors. (HLW)
Date: January 1, 1975
Creator: Setlow, R.B.
Partner: UNT Libraries Government Documents Department

uv photobiology: postreplication repair. [Escherichia coli, synchrotron radiation]

Description: The following topics are discussed: insertion of incorrect bases in DNA; ability of DNA polymerase to copy uv-irradiated DNA; role of enzymes in repair of DNA; effects of uv radiation on molecular weight of DNA; photoreactivation; repair of DNA in Escherichia coli and xp cells following uv radiation; and synchrotron radiation studies on DNA repair. (HLW)
Date: January 1, 1978
Creator: Sutherland, B M
Partner: UNT Libraries Government Documents Department

uv photobiology: DNA damage and repair

Description: The following topics are discussed: targets that determine the fate of the cell when uv light interacts with a cell; comparison of action spectrum for a given biological effect with the absorption spectrum of different biological macromolecules; biological effects of damage to DNA; measurement of mutations; chemical damage to DNA; photoreactivation; role of pyrimidine dimers in induction of skin cancer by uv. (HLW)
Date: January 1, 1978
Creator: Sutherland, B M
Partner: UNT Libraries Government Documents Department

Photoreactivation in bacteria and in skin

Description: In many procaryotic and eucaryotic cells, photoreactivating enzyme mediates light-dependent repair of uv-induced damage; the enzyme binds to a pyrimidine dimer in DNA, and, on absorption of a photon (300 to 600 nm), specifically monomerizes the dimer, thus repairing the DNA. Photoreactivating enzyme has been found in human tissues and human cells in culture can photoreactivate cellular dimers, and can mediate photoreactivation of Herpes (human fibroblasts) and Epstein-Barr virus (human leukocytes). Measurements of pyrimidine dimer formation and repair in human skin indicate that detectable numbers of dimers are formed at 1 minimal erythemal dose, that the dimiers are rapidly removed in skin kept in the absence of light, and they are more rapidly removed when the skin is exposed to visible light. Whether this apparent photorecovery is true, enzymatic photoreactivation is yet to be determined.
Date: January 1, 1980
Creator: Sutherland, B M
Partner: UNT Libraries Government Documents Department

Photochemistry of psoralen-DNA adducts, biological effects of psoralen-DNA adducts, applications of psoralen-DNA photochemistry

Description: This thesis consists of three main parts and totally eight chapters. In Part I, The author will present studies on the photochemistry of psoralen-DNA adducts, specifically, the wavelength dependencies for the photoreversals of thymidine-HMT (4'-hydroxymethyl-4, 5', 8-trimenthylpsoralen) monoadducts and diadduct and the same adducts incorporated in DNA helices and the wavelength dependecies for the photocrossslinking of thymidine-HMT monoadducts in double-stranded helices. In Part II, The author will report some biological effects of psoralen-DNA adducts, i.e., the effects on double-stranded DNA stability, DNA structure, and transcription by E. coli and T7 RNA polymerases. Finally, The author will focus on the applications of psoralen-DNA photochemistry to investigation of protein-DNA interaction during transcription, which includes the interaction of E. coli and T7 RNA polymerases with DNA in elongation complexes arrested at specific psoralen-DNA adduct sites as revealed by DNase I footprinting experiments. 123 refs., 52 figs., 12 tabs.
Date: March 1, 1988
Creator: Shi, Yun-bo
Partner: UNT Libraries Government Documents Department

Genotoxic effects of sunlight-activated waste waters

Description: Natural sunlight induces a genotoxic response in cultured CHO cells pre-treated with shale oil retort process water. Near ultraviolet light (NUV) component of the solar spectrum is the apparent radiation responsible for photoactivation. Cultured human skin fibroblasts are acutely sensitive to the genotoxic effects of photoactivated process water. The mutagenic potential of photoactivated process water in human cells is the same as that witnessed for an equivalent killing dose of the potent skin carcinogen FUV. DNA repair processes are involved in modulating genotoxic effects of this photo-induced process. The exact magnitude of the potential health-related and environmental risks resulting from photoactivation of retort process waters and other oil shale by-products is unassessed at this time. Our demonstration that a significant rate of mutation occurs in cultured human cells exposed to high dilutions of process waters and fluences of NUV comparable to that encountered during nominal exposure to sunlight suggests that such assessment is a prerequisite to minimal risk development of our oil shale resources.
Date: January 1, 1981
Creator: Strniste, G.F.; Chen, D.J. & Okinaka, R.T.
Partner: UNT Libraries Government Documents Department