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Analysis of thermally-stable electron transport factors from the hyperthermophilic archaebacterium Pyrodictium brockii

Description: The mechanisms by which hyperthermophilic archaebacteria grow and carry out metabolic functions at elevated temperatures have yet to be determined. The objective of this work is to develop an understanding of the metabolic characteristics of, and the electron transport enzymes involved in, hydrogen/sulfur transformation by hyperthermophilic archaebacteria. Efforts focus on the autotrophic H{sub 2}-oxidizing bacterium, Pyrodictium brockii which has an optimum growth temperature of 105{degrees}C. Biochemical and genetic characterization of enzymes involved in hydrogen oxidizing electron transport pathway. These including investigating the role of the membrane lipids in protecting the hydrogenase enzyme from thermal inactivation, characterization of a quinone and a c-type cytochrome, and analysis of the topology in the membrane in the net energy generating components are reported. The long-term goal is to understand some of the factors contributing to the biochemical basis of extreme thermophily.
Date: September 1, 1992

Analysis of thermally-stable electron transport factors from the hyperthermophilic archaebacterium Pyrodictium brockii. Progress report

Description: The mechanisms by which hyperthermophilic archaebacteria grow and carry out metabolic functions at elevated temperatures have yet to be determined. The objective of this work is to develop an understanding of the metabolic characteristics of, and the electron transport enzymes involved in, hydrogen/sulfur transformation by hyperthermophilic archaebacteria. Efforts focus on the autotrophic H{sub 2}-oxidizing bacterium, Pyrodictium brockii which has an optimum growth temperature of 105{degrees}C. Biochemical and genetic characterization of enzymes involved in hydrogen oxidizing electron transport pathway. These including investigating the role of the membrane lipids in protecting the hydrogenase enzyme from thermal inactivation, characterization of a quinone and a c-type cytochrome, and analysis of the topology in the membrane in the net energy generating components are reported. The long-term goal is to understand some of the factors contributing to the biochemical basis of extreme thermophily.
Date: September 1, 1992

Annual Report. Part A: Studies in K-Capture Positron Branching Ratios. Part B: Search for a Low-Lying O+ State in Gallium-68

Description: K-capture to positron branching ratios were measured in the decay of Na/ sup 22/, Co/sup 58/, and Ga/sup 68/ -- all pure Gamow-Teller emitters, using coincidence scintillation spectrometer techniques. The measured values are 0.105 plus or minus 0.004 for Na/sup 22/, 5.08 plus or minus 0.17 for Co/sup 58/, and 1.28 plus or minus 0.12 and 0.10 plus or minus 0.02 for Ga/sup 58/. From these the Fierz interference terra is computed to be b =--0.004 plus or minus 0.012, -0.004 plus or minus 0.14, --0-03 plus or minus 0.02, and +0.03 plus or minus 0.01, respectively. These results indicate that the Fierz interference in Gamow-Teller interaction is very small. The decay of 270 day Ge/sup 68/ was investigated in equilibrium with Ga/sup 68/ to look for a possible low-lying 0+ level in Ga/sup 68/ using x-ray--x-ray and x-ray- gamma -ray coincidences. The result was negative. Besides the 9 kev K x ray, the 1.07 Mev gamma ray in the decay of Ga/sup 68/ and annihilation radiation, no other gamma rays were detected (<8% of 1.07 Mev gamma ray). The number of positrons per 1.07 Mev gamma - quantum was determined as 19.47 plus or minus 2.10. The ratio of positrons to the 1.07 Mev level and ground state of Zn/sup 68/ was found to be (1.76 plus or minus 0.22) x 10/sup -2/. Studies with a Ge/sup 68/ source chemically separated from Ga/sup 68/ showed no gamma rays (<1% of total Ge/sup 68/ decays). By following the growth of annihilation radiation, an upper limit of 0.4% per decay cculd be set on the amount of positron emission by Ge/sup 68/. A search for an electric monopole (EO) transition from the 2.3 Mev level to the O/sup +/ ground state of Zn/sup 68/ was made using plastic scintillators and an …
Date: August 1, 1959
Creator: Madansky, L. & Ramaswamy, M.

Behavior of Institutional Incinerators When Used to Burn Radioactive Wastes: Final Project Report for August 1, 1950-November 1, 1952

Description: This report deals with the development of methods and techniques for measuring the amounts of radioisotope on the stack wall, in ash, stack gas and atmosphere during and after incineration in the conventional refuse-type destructor.
Date: November 1, 1952
Creator: Kruse, C. W.; Freese, P. V.; Machis, A. & Behn, V. C.

City Smoke Ordinances and Smoke Abatement

Description: From Introduction: "In connection with the fuel investigations conducted by the Bureau of Mines much information has been accumulated as to the smoke abatement activities in various cities. The essential features of the information are presented in this report, which, it is believed, will be of public interest and benefit, especially to those communities that are just beginning organized effort to abate unnecessary smoke."
Date: 1912
Creator: Flagg, Samuel B.

Final Technical Report, Outstanding Junior Investigator Award for De-fg02-94er40869

Description: This report summarizes the research of the Principal Investigator, his postdoctoral research associates, and his students during the period of the award. The majority of the work concerns the behavior of hadrons containing strange, charm, bottom and top quarks, with a particular focus on the extraction of Cabibbo--Kobayashi--Maskawa matrix elements from experiments performed on such systems.
Date: May 16, 2002
Creator: Falk, Adam F.

Genes and gene expression: Localization, damage and control -- A multi-level and interdisciplinary study

Description: This progress report describes gains made in three projects entitled (1) 3-Dimensional nuclear topography of genes and chromosomes in interphase nuclei, (2) Sequence specific identification and perturbation of the genomic DNA in living cells by nonionic oligonucleotide analogs (Matagen), and Resolution and isolation of specific DNA restriction fragments.(DT)
Date: August 1, 1992
Creator: Ts'o, P.O.P.

Genes and gene expression: Localization, damage and control -- A multi-level and interdisciplinary study. Progress report, February 1, 1992--January 31, 1993

Description: This progress report describes gains made in three projects entitled (1) 3-Dimensional nuclear topography of genes and chromosomes in interphase nuclei, (2) Sequence specific identification and perturbation of the genomic DNA in living cells by nonionic oligonucleotide analogs (Matagen), and Resolution and isolation of specific DNA restriction fragments.(DT)
Date: August 1, 1992
Creator: Ts`o, P. O. P.

Geothermal Energy Development in the Eastern United States. A Program for Capital Recovery Assessment for the HP-97 and Other Desk Calculators

Description: The Johns Hopkins University Applied Physics Laboratory and the Center for Metropolitan Planning and Research support the Division of Geothermal Energy, U.S. Department of Energy, in the development of geothermal energy in the Eastern United States. In this role, many tools have been developed to assist in the analysis of the economics of the application of geothermal energy. This report documents one computer program that has proved useful.
Date: August 7, 1980
Creator: Yu, Kwang & Briesen, Roy Von

Geothermal Energy Development in the Eastern United States, Sensitivity analysis-cost of geothermal energy

Description: The Geothermal Resources Interactive Temporal Simulation (GRITS) model is a computer code designed to estimate the costs of geothermal energy systems. The interactive program allows the user to vary resource, demand, and financial parameters to observe their effects on delivered costs of direct-use geothermal energy. Due to the large number and interdependent nature of the variables that influence these costs, the variables can be handled practically only through computer modeling. This report documents a sensitivity analysis of the cost of direct-use geothermal energy where each major element is varied to measure the responsiveness of cost to changes in that element. It is hoped that this analysis will assist those persons interested in geothermal energy to understand the most significant cost element as well as those individuals interested in using the GRITS program in the future.
Date: December 1, 1982
Creator: Kane, S.M.; Kroll, P. & Nilo, B.

Geothermal Energy Market Study on the Atlantic Coastal Plain. A Review of Recent Energy Price Projections for Traditional Space Heating Fuel 1985-2000

Description: In order to develop an initial estimate of the potential competitiveness of low temperature (45 degrees C to 100 degrees C) geothermal resources on the Eastern Coastal Plain, the Center for Metropolitant Planning and Research of The Johns Hopkins University reviewed and compared available energy price projections. Series of projections covering the post-1985 period have been made by the Energy Information Administration, Brookhaven National Laboratory, and by private research firms. Since low temperature geothermal energy will compete primarily for the space and process heating markets currently held by petroleum, natural gas, and electricity, projected trends in the real prices for these fuels were examined. The spread in the current and in projected future prices for these fuels, which often serve identical end uses, underscores the influence of specific attributes for each type of fuel, such as cleanliness, security of supply, and governmental regulation. Geothermal energy possesses several important attributes in common with electricity (e.g., ease of maintenance and perceived security of supply), and thus the price of electric space heating is likely to be an upper bound on a competitive price for geothermal energy. Competitiveness would, of course, be increased if geothermal heat could be delivered for prices closer to those for oil and natural gas. The projections reviewed suggest that oil and gas prices will rise significantly in real terms over the next few decades, while electricity prices are projected to be more stable. Electricity prices will, however, remain above those for the other two fuels. The significance of this work rests on the fact that, in market economies, prices provide the fundamental signals needed for efficient resource allocation. Although market prices often fail to fully account for factors such as environmental impacts and long-term scarcity value, they nevertheless embody a considerable amount of information and are the primary …
Date: March 1, 1979
Creator: Weissbrod, Richard & Barron, William

Investigation of the processes controlling the flame generation of refractory materials. Progress report, July 1, 1991--June 30, 1992

Description: The processes involved in the formation of mixed oxides powders were studied using the counterflow diffusion flame burner. Powders of different morphologies were obtained by varying the flame conditions (temperature, residence time) and the concentration ratio of the oxides precursors. In-situ particle size and number density were determined using dynamic light scattering and 90{degrees} light scattering. A thermophoretic sampling method and a larger scale powder collection device also was used to collect particles, and their size and morphology examined using transmission electron microscopy, X-ray diffraction and surface area measurement by gas absorption (BET). Our emphasis has been on TiO{sub 2}-SiO{sub 2}, SiO{sub 2}-GeO{sub 2} and Al{sub 2}O{sub 3}-TiO{sub 2}. The powders had a core-mantle-like (one oxide coated by the other) at low elevations in the burner and uniform mixture at higher elevations. They form chain-like structures in a low temperature flame and spherical particles in a higher temperature flame. Nanometer sized homogeneous particles of Aluminum Titanate could be obtained using Al(CH{sub 3}){sub 3} and TiCl{sub 4} as precursors both in a hydrogen fueled and a methane fueled counterflow diffusion flame burner, as well as in a hydrogen fueled parallel-flow diffusion flame burner.
Date: January 1, 1992
Creator: Katz, J. L.

Numerical and Physical Modelling of Bubbly Flow Phenomena - Final Report to the Department of Energy

Description: This report describes the main features of the results obtained in the course of this project. A new approach to the systematic development of closure relations for the averaged equations of disperse multiphase flow is outlined. The focus of the project is on spatially non-uniform systems and several aspects in which such systems differ from uniform ones are described. Then, the procedure used in deriving the closure relations is given and some explicit results shown. The report also contains a list of publications supported by this grant and a list of the persons involved in the work.
Date: December 21, 2004
Creator: Prosperetti, Andrea

Photoinduced nucleation: a new technology for the detection of chemical contaminants. Final Report

Description: This research grant supported the creation and initial development of a new kind of chemical detector; one that can detect species at part per trillion levels because it does not rely on the direct measurement of a species presence; rather, it uses an indirect measurement of the effect of the trace species on the condensation nucleation of a supersaturated vapor. Since this nucleation process is extremely sensitive to the concentrations of certain types of impurities, this nucleation-based detection can be made more sensitive than any current spectroscopic detector.
Date: September 30, 2003
Creator: Katz, Joseph L.
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