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Analysis of thermally-stable electron transport factors from the hyperthermophilic archaebacterium Pyrodictium brockii
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.
Analysis of thermally-stable electron transport factors from the hyperthermophilic archaebacterium Pyrodictium brockii. Progress report
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.
Annual Report. Part A: Studies in K-Capture Positron Branching Ratios. Part B: Search for a Low-Lying O+ State in Gallium-68
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 …
Bacterial Nickel Metabolism and Storage. Final Technical Report for Period January 1, 1994 - August 31, 1998
This report describes results on six years of research on how bacteria store nickel and then mobilize it into the active center of enzymes.
Behavior of Institutional Incinerators When Used to Burn Radioactive Wastes: Final Project Report for August 1, 1950-November 1, 1952
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.
City Smoke Ordinances and Smoke Abatement
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."
(Development of a Human Genome Data Base)
This report describes managerial aspects and briefly some technical accomplishments a Human Genome Database in Baltimore.
[Development of a Human Genome Data Base]. Progress report
This report describes managerial aspects and briefly some technical accomplishments a Human Genome Database in Baltimore.
AN EVALUATION OF LAUNDERING AGENTS AND TECHNIQUES USED IN THE DECONTAMINATION OF COTTON CLOTHING
No Description Available.
The Feldspars of the New England and North Appalachian States
From Introduction: "The investigations presented in this bulletin have been undertaken by the bureau with a view to a better understanding of the conditions which confront the producer of commercial feldspar and also with the object of determining wherein the various deposits of feldspar differ."
Final Report: A Level-of-Detail Approach to Cluster-based Visualization
In this research project we have tightly integrate the use of level of detail with PC cluster-based rendering systems.
Final Technical Report, Outstanding Junior Investigator Award for De-fg02-94er40869
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.
The Gabbros and Associated Hornblende Rocks Occurring in the Neighborhood of Baltimore, Maryland
From introduction: The present paper is intended as a contribution to our knowledge of a particular phase of metamorphism in eruptive rocks, i.e., that one which is dependent on the secondary development of hornblende by the paramorphism or pseudomorphism of pyroxene.
Genes and gene expression: Localization, damage and control -- A multi-level and interdisciplinary study
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)
Genes and gene expression: Localization, damage and control -- A multi-level and interdisciplinary study. Progress report, February 1, 1992--January 31, 1993
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)
Geothermal Energy and the Eastern U.S. Progress Report
No Description Available.
Geothermal Energy Development in the Eastern United States. A Program for Capital Recovery Assessment for the HP-97 and Other Desk Calculators
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.
Geothermal Energy Development in the Eastern United States, Sensitivity analysis-cost of geothermal energy
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.
Geothermal Energy Market Study on the Atlantic Coastal Plain. A Review of Recent Energy Price Projections for Traditional Space Heating Fuel 1985-2000
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 …
Investigation of the processes controlling the flame generation of refractory materials. Progress report, July 1, 1991--June 30, 1992
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.
A Novel Method for the Removal of Trace Concentration of Elemental Mercury From Utility Emissions
A new technique for removal of elemental mercury from emissions of coal-fired utilities was investigated. The key idea is to selectively photo ionize the mercury atoms. A strong electric field gradient then drags them to the negative plate where they can be collected and removed.
Numerical and Physical Modelling of Bubbly Flow Phenomena - Final Report to the Department of Energy
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.
Papers Presented - Geothermal Resources Council 1980 Annual Meeting
This report contains preprints of papers pertaining to geothermal energy development in the Eastern United States written by members of the Center for Metropolitan Planning and Research (Metro Center) and by the Applied Physics Laboratory (APL) both of The Johns Hopkins University.
Photoinduced nucleation: a new technology for the detection of chemical contaminants. Final Report
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.
Progress Report for the grant "Hight-Resolution Mineralogical Charaterization and Biogeochemical Modeling of Uranium Reduction Pathways at the NABIR Field-Research Center"
We have successfully completed a proof-of-concept, one-year grant on a three-year proposal from the former NABIR program. Using a state-of-the-art 300-kV, atomic resolution, Field Emission Gun Transmission Electron Microscope (TEM), we have successfully identified three categories of mineral hosts for uranium in contaminated soils from the Oak Ridge FRC: (1) iron oxides: (2) mixed manganese-iron oxides; and (3) uranium phosphates.
Radioactive Waste Disposal Practices in the Atomic Energy Industry. A Survey of the Costs
A survey was made on methcds and related costs of disposing of radioactive wastes as practiced in 1955 by twelve atomic industry installations. Wherever possible, estimated unit costs of differentiated stages of waste handling are shown- these are integrated to show the over-all scope of waste dispesal practices at each site. Tabular data summarize costs and operation magnitades at the installations. A pattern is established for standardizing the reporting of fixed costs and equipment unsage costs. The economy of solid waste volume reduction is analyzed. Material costs are listed. An outline for recording monthly waste disposal costs is presented. Obvious conclusions drawn from the factual data are: that it is more expensive per cubic foot to handle high-level wastes than low-level wastes. and that land disposal is less expenaive than sea disposal. A reexamination of baling economics shows that high compression of solid wastes is more expensive than simpler forms of compaction. (auth)
Regional aerosol deposition in human upper airways
During the current report experimental studies of upper respiratory deposition of radon progeny aerosols and stimulant aerosols were carried out in replicate casts of nasal and oral passages of adults and children. Additionally, preliminary studies of nasal passage deposition of unattached Po{sup 218} particles was carried out in four human subjects. Data on nasal inspiratory deposition in replicate models of adults and infants from three collaborating laboratories were compared and a best-fit curve of deposition efficiency for both attached and unattached particles was obtained, showing excellent inter-laboratory agreement. This curve demonstrates that nasal inspiratory deposition of radon progeny is weakly dependent upon flow rate over physiologically realistic ranges of flow, does not show a significant age effect, and is relatively independent of nasal passage dimensions for a given age range. Improved replicate models of the human adult oral passage extending to the mid-trachea were constructed for medium and higher flow mouth breathing states; these models were used to assess the deposition of unattached Po{sup 218} particles during oronasal breathing in the oral passage and demonstrated lower deposition efficiency than the nasal passage. Measurements of both Po{sup 218} particle and attached fraction particle size deposition were performed in replicate nasal passage of a four week old infant. 5 refs., 1 fig.
Search for the microscopic origin of defects and shear localization in metallic glasses
This proposed research addresses one of the long outstanding fundamental problems in materials science, the mechanisms of deformation in amorphous metals. Due to the lack of long-range translational order, details of structural defects and their behaviors in metallic glasses have not been accessible in experiments. In addition, the small dimensions of the amorphous alloys made early by rapid quenching impose severe limit on many standard mechanical and microscopy testing. As a result, the microscopic mechanism of deformation in the amorphous materials has not been established. The recent success in synthesis of bulk metallic glass overcomes the difficulty in standard testing; but the barrier for understanding the defect process and microscopic mechanisms of deformation still remains. Amorphous metals deform in a unique way by shear banding. As a result, there is no work hardening, little macroscopic plasticity, and catastrophic failure. To retain and improve the inherent high strength, large elastic strain, and high toughness in amorphous metals, a variety of synthesis activities are currently underway including making metallic glass matrix composites. These new explorations call for a quantitative understanding of deformation mechanisms in both the monolithic metallic glasses as well as their composites. The knowledge is expected to give insight and guide to design, processing and applications of this new generation of engineering materials. This DOE funded research takes the approach of computer simulation and modeling to tackle this problem. It is expected that with the increasing power of computers, the numerical modeling could provide the answers that are difficult or impossible to get from experiments. Three parallel research tasks were planned in this work. One is on search of atomic structural defects and other microscopic mechanisms underlying the deformation process. The second is the formulate a general model to describe shear localization, shear band formation and propagation on mesoscopic scale. …
Spectroscopic diagnostics of high temperature plasmas, January 1, 1991--December 31, 1991
During 1991, the activities of the John Hopkins University Plasma Spectroscopy Group have covered several areas of research, in the domain of XUV spectroscopy of magnetically confined fusion plasmas. While the main effort concentrated on the development of novel diagnostics which utilize Layered Synthetic Microstructures (LSMs) as the dispersive/filtering elements, work has been done in the area of detector development and the physics of the tokamak edge plasma. An XUV monochromator for the 20--200{Angstrom} range, which uses flat LSMs, has been built and is currently operated on the D3-D tokamak at General Atomics in San Diego. A design for a follow-up experiment at D3-D is now in progress. As a preliminary step toward tokamak plasma imaging in the XUV wavelength range using curved LSM coated substrates, a prototype XUV camera was built and operated in our laboratory in image the A1 3 emission at {lambda}-175{Angstrom} from a Penning Ionization Discharge plasma. Based on these laboratory results, the design of the XUV camera, which will image plasma in the Phaedrus T tokamak O VI emission (150{Angstrom}), has been completed. This instrument is presently under construction. Also a detailed design of a system composed of four LSM based imaging devices for N{sub e}(0) and T{sub e}(0) fluctuation measurements on TEXT has been completed. The accuracy and the uniformity of the LSM coatings on flat and small curved surfaces used in the above-mentioned instruments have been evaluated in our laboratory using an in-house built calibration facility and at the SURF II synchrotron at the National Institute of Standards and Technology.
STAR Electromagnetic Calorimeter R&D Progress Report, 1 October 1992--31 August 1993
A lead-scintillator sampling electromagnetic calorimeter (EMC) is planned as an upgrade to the STAR detector for the RHIC Accelerator at Brookhaven National Laboratory (BNL). Considerable work on the conceptual design of the calorimeter, and related interfacing issues with the solenoids magnet and the time projection chamber (TPC) subsystems of STAR occurred in the period 1 October 1992 to 31 August 1993 (FY 1993). This report documents and summarizes the conclusions and progress from this work.
Statistical Analysis of the Frequency and Severity of Accidents to Potential Highway Carriers of Highly Radioactive Materials
The probability of accidents to tractor semitrailers is developed through analysis of accident frequency data in relation to season; geographical factors; road type, traffic and populatlon density; and type of carrier business. Maximum likelihood rates are developed for the potential carriers of radioactivity. Impact characteristics of accidents are studied through the analysis of mass, speed, and energy relations and the effect of these on vehicle and cargo damages is explored. (auth)
STUDIES OF FAST NEUTRONS AND FAST NEUTRON REACTIONS
No Description Available.
Studies of relativistic heavy ion collisions. Annual progress report, August 1, 1992--July 31, 1993
With the completion of the experimental runs with the DLS, which included both heavy ion and nucleon projectiles and targets, is being completed the analysis of these high statistics experiments. The Hopkins group has a major responsibility in comparing the experimental results with recently developed simulation codes for a theoretical comparison. The second major activity involves the STAR experiment at RHIC, to continued involvement with simulations and development of prototypes of detector systems is expected. The program for studying optical properties of mirrors and gas scintillations related to Cerenkov ring imaging will continue.
Transport of Ions Across the Inner Envelope Membrane of Chloroplasts
The technical report outlines the results of nine years of research on how ions cross the inner envelope membrane of chloroplasts. The ions include protons, nitrite, calcium and ferrous iron. Bicarbonate transport was also studied.
Transport of Radionuclides in Fresh Water Systems. Report of a Working Meeting Held at University of Texas, Austin, January 30-February 1, 1963
Nineteen papers presented at the Conference on the Transport of Radionuclides in Fresh Water Systems are given. Separate abstracts were prepared for 18 papers; one was previously abstracted for NSA. (M.C.G.)
The Unstable Species and the Isotope Effect in the Pyrolysis of Diborane in a Shock Tube
From American Chemical Society 145th National Meeting, New York, Sept. 1963. The pyrolysis of diborane was examined using a chemical shock tube as a reactor. Additional evidence for the existence of hexaborane-12 and heptaborane- 11 and -13 was obtained. The presence of a large net normal isotope effect in the formation of tetraborane and hexaborane and a net inverse isotope effect in the formation of pentaborane-9 are observed. A mechanism, consisting of a series of competitive reactions and eqailibria, in which tetraboraue is the precursor of pentaborane-11 and hexaborane but not of pentaborane-9 is shown to be compatible with the observed isotope effect. Data obtained by examining the pyrolysis of various mixtures of boron hydrides are also consistent with the mechanism. (auth)
USXR Based MHD, Transport, Equilibria and Current Profile Diagnostics for NSTX. Final Report
The present report resumes the research activities of the Plasma Spectroscopy/Diagnostics Group at Johns Hopkins University performed on the NSTX tokamak at PPPL during the period 1999-2009. During this period we have designed and implemented XUV based diagnostics for a large number of tasks: study of impurity content and particle transport, MHD activity, time-resolved electron temperature measeurements, ELM research, etc. Both line emission and continuum were used in the XUV range. New technics and novel methods have been devised within the framework of the present research. Graduate and post-graduate students have been involved at all times in addition to the senior research personnel. Several tens of papers have been published and lectures have been given based on the obtained results at conferences and various research institutions (lists of these activities were attached both in each proposal and in the annual reports submitted to our supervisors at OFES).
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