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Analysis of thermally-stable electron transport factors from the hyperthermophilic archaebacterium Pyrodictium brockii (open access)

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.
Date: September 1, 1992
Creator: unknown
System: The UNT Digital Library
Studies of relativistic heavy ion collisions. Annual progress report, August 1, 1992--July 31, 1993 (open access)

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.
Date: August 1, 1993
Creator: Madansky, L.
System: The UNT Digital Library
Genes and gene expression: Localization, damage and control -- A multi-level and interdisciplinary study. Progress report, February 1, 1992--January 31, 1993 (open access)

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)
Date: August 1, 1992
Creator: Ts`o, P. O. P.
System: The UNT Digital Library
(Development of a Human Genome Data Base) (open access)

(Development of a Human Genome Data Base)

This report describes managerial aspects and briefly some technical accomplishments a Human Genome Database in Baltimore.
Date: January 1, 1992
Creator: unknown
System: The UNT Digital Library
USXR Based MHD, Transport, Equilibria and Current Profile Diagnostics for NSTX. Final Report (open access)

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).
Date: June 1, 2009
Creator: Finkenthal, Michael
System: The UNT Digital Library
Final Report: A Level-of-Detail Approach to Cluster-based Visualization (open access)

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.
Date: November 20, 2009
Creator: Cohen, Jonathan
System: The UNT Digital Library
The Gabbros and Associated Hornblende Rocks Occurring in the Neighborhood of Baltimore, Maryland (open access)

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.
Date: 1886
Creator: Williams, George Huntington
System: The UNT Digital Library
Geothermal Energy and the Eastern U.S. Progress Report (open access)

Geothermal Energy and the Eastern U.S. Progress Report

None
Date: June 2, 1980
Creator: unknown
System: The UNT Digital Library
The Unstable Species and the Isotope Effect in the Pyrolysis of Diborane in a Shock Tube (open access)

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)
Date: January 1, 1963
Creator: Fehlher, T P & Koski, W S
System: The UNT Digital Library
Geothermal Energy Market Study on the Atlantic Coastal Plain. A Review of Recent Energy Price Projections for Traditional Space Heating Fuel 1985-2000 (open access)

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 …
Date: March 1, 1979
Creator: Weissbrod, Richard & Barron, William
System: The UNT Digital Library
STUDIES OF FAST NEUTRONS AND FAST NEUTRON REACTIONS (open access)

STUDIES OF FAST NEUTRONS AND FAST NEUTRON REACTIONS

None
Date: October 1, 1952
Creator: unknown
System: The UNT Digital Library
Behavior of Institutional Incinerators When Used to Burn Radioactive Wastes: Final Project Report for August 1, 1950-November 1, 1952 (open access)

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.
Date: November 1, 1952
Creator: Kruse, C. W.; Freese, P. V.; Machis, A. & Behn, V. C.
System: The UNT Digital Library
AN EVALUATION OF LAUNDERING AGENTS AND TECHNIQUES USED IN THE DECONTAMINATION OF COTTON CLOTHING (open access)

AN EVALUATION OF LAUNDERING AGENTS AND TECHNIQUES USED IN THE DECONTAMINATION OF COTTON CLOTHING

None
Date: March 1, 1954
Creator: Talboys, A.P. & Spratt, E.C.
System: The UNT Digital Library
Numerical and Physical Modelling of Bubbly Flow Phenomena - Final Report to the Department of Energy (open access)

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.
Date: December 21, 2004
Creator: Prosperetti, Andrea
System: The UNT Digital Library
A Novel Method for the Removal of Trace Concentration of Elemental Mercury From Utility Emissions (open access)

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.
Date: September 17, 2002
Creator: Katz, Joseph L.
System: The UNT Digital Library
Transport of Ions Across the Inner Envelope Membrane of Chloroplasts (open access)

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.
Date: June 2, 2004
Creator: McCarty, R. E.
System: The UNT Digital Library
Final Technical Report, Outstanding Junior Investigator Award for De-fg02-94er40869 (open access)

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.
Date: May 16, 2002
Creator: Falk, Adam F.
System: The UNT Digital Library
Search for the microscopic origin of defects and shear localization in metallic glasses (open access)

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 …
Date: November 10, 2001
Creator: Li, Mo
System: The UNT Digital Library
Bacterial Nickel Metabolism and Storage. Final Technical Report for Period January 1, 1994 - August 31, 1998 (open access)

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.
Date: March 1, 2001
Creator: Maier, Robert J.
System: The UNT Digital Library
Photoinduced nucleation: a new technology for the detection of chemical contaminants. Final Report (open access)

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.
Date: September 30, 2003
Creator: Katz, Joseph L.
System: The UNT Digital Library
Statistical Analysis of the Frequency and Severity of Accidents to Potential Highway Carriers of Highly Radioactive Materials (open access)

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)
Date: July 1, 1961
Creator: Leimkuhler, F.F.; Karson, M.J. & Thompson, J.T.
System: The UNT Digital Library
Annual Report. Part A: Studies in K-Capture Positron Branching Ratios. Part B: Search for a Low-Lying O+ State in Gallium-68 (open access)

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 …
Date: August 1, 1959
Creator: Madansky, L. & Ramaswamy, M.
System: The UNT Digital Library
Transport of Radionuclides in Fresh Water Systems. Report of a Working Meeting Held at University of Texas, Austin, January 30-February 1, 1963 (open access)

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.)
Date: July 1, 1963
Creator: Kornegay, B. H.; Vaughan, W. A.; Jamison, D. K. & Morgan, J. M., Jr.
System: The UNT Digital Library
Genes and gene expression: Localization, damage and control -- A multi-level and interdisciplinary study (open access)

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)
Date: August 1, 1992
Creator: Ts'o, P.O.P.
System: The UNT Digital Library