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Brookhaven highlights for fiscal year 1991, October 1, 1990--September 30, 1991

Description: This report highlights Brookhaven National Laboratory's activities for fiscal year 1991. Topics from the four research divisions: Computing and Communications, Instrumentation, Reactors, and Safety and Environmental Protection are presented. The research programs at Brookhaven are diverse, as is reflected by the nine different scientific departments: Accelerator Development, Alternating Gradient Synchrotron, Applied Science, Biology, Chemistry, Medical, National Synchrotron Light Source, Nuclea… more
Date: January 1, 1991
Creator: Rowe, M.S.; Cohen, A.; Greenberg, D.; Seubert, L. & Kuper, J.B.H.
Partner: UNT Libraries Government Documents Department
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Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

Description: The objective of this project is to provide the fundamental information on the mechanisms of bacterial leaching of pyrite. The knowledge of how bacterial leaching of pyrite functions is essential for design and development of a technology for coal cleaning with bacteria. The features of major electrochemical techniques will be examined to find out if any of them can provide a diagnostic information on the mechanisms of related reactions.
Date: January 1, 1992
Creator: Pesic, B.
Partner: UNT Libraries Government Documents Department
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Photoinduced Charge Separation by Polymer-Bound Chromophores

Description: This project has examined the photodynamic behavior of water-soluble polymers that have covalently linked hydrophobic chromophores spaced along the chains. These polymeric systems have been examined for photoinduced charge separation with electron-accepting ions having different total charge. Focus has been on the excited singlet (S{sub 1}) state formed by laser flash absorption. The effects of pH and ionic strength -- factors that govern the conformational nature of the polymer in solution -- … more
Date: September 1, 1991
Creator: Rodgers, M. A. J.
Partner: UNT Libraries Government Documents Department
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Programmable multi-timer for TRU waste analysis applications

Description: A programmable, multiple-function timing module has been developed for use in transuranic (TRU) waste analysis applications at the Idaho National Engineering Laboratory. The Programmable Multi-Timer (PRMT) is an expanded version of a module originally built for accelerator-based active photon interrogation experiments. During the course of the experiments, it became obvious that a more versatile timer was needed to meet several unforeseen requirements. The PRMT was designed to meet the new requ… more
Date: January 1, 1981
Creator: Lawrence, R.S.; Nieschmidt, E.B. & Tsang, F.Y.
Partner: UNT Libraries Government Documents Department
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Institutional research and development, FY 1987

Description: The Institutional Research and Development program at Lawrence Livermore National Laboratory fosters exploratory work to advance science and technology, disciplinary research to develop innovative solutions to problems in various scientific fields, and long-term interdisciplinary research in support of defense and energy missions. This annual report describes research funded under this program for FY87. (DWL)
Date: January 1, 1987
Creator: Struble, G. L.; Lawler, G. M.; Crawford, R. B.; Kirvel, R. D.; Peck, T. M.; Prono, J. K. et al.
Partner: UNT Libraries Government Documents Department
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High-Sensitivity Single-Molecule Fluorescence Detection in Theory and Practice

Description: The number of emitted photons that can be obtained from a fluorophore increases with the incident light intensity and the duration of illumination. However, saturation of the absorption transition and photodestruction place natural limits on the ultimate signal-to-noise ratio that can be obtained. Equations have been derived to describe the fluorescence-to-background-noise ratio in the presence of saturating light intensities and photodestruction. The fluorescence lifetime and the photodestruct… more
Date: 1989
Creator: Mathies, R. A.; Peck, K. & Stryer, L.
Partner: UNT Libraries Government Documents Department
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NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts

Description: Copper and cobalt are the key elements in syngas conversion catalyst systems used for higher alcohol synthesis. Their proximity and synergy sensitively control the selectivity and efficiency of the process. It is believed that their outer electronic charge distribution which is responsible for their electrical and magnetic properties might be governing their catalytic properties also. To examine the correlation between catalytic and magnetic properties, a series of copper cobalt catalysts (Co/C… more
Date: January 14, 1991
Partner: UNT Libraries Government Documents Department
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Methane oxidation over dual redox catalysts

Description: Review and analysis of the literature data on electron transfer itself and electron transfer oxidation of alkyl radicals was done in order to understand the mechanism by which methyl radical can be oxidized to CH{sub 3}{sup +} and further substituted by OH{sup {minus}} to form methanol. This allowed to compare and classify the various possible reaction patterns, understand the mechanism and circumstances of operation of each of them and select those which can be involved in oxidation of methyl … more
Date: March 1, 1989
Creator: Klier, Kamil; Herman, Richard G. & Sojka, Zvigniew
Partner: UNT Libraries Government Documents Department
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Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties

Description: Several new types of silicon-containing preceramic polymers, i.e., poly(diorganosilacetylene) and poly(diorganosilvinylene) have been synthesized with molecular weights from 10,000 to 120,000. These polymers could be thermally converted to SiC with a moderate to high char yields. Ready solubility and good processability made these types of polymers attractive in their applications to ceramics. The thermal polymerization of diethynyldiphenyl-silane, which was reported in 1968 to afford poly(diph… more
Date: October 7, 1991
Creator: Pang, Yi.
Partner: UNT Libraries Government Documents Department
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Thermodynamic model for calorimetric and phase coexistence properties of coal derived fluids

Description: On September 1, 1989 work was initiated on a project to extend the available vapor-liquid equilibrium (VLE) model for coal fluids to allow satisfactory predictions of excess enthalpies of coal liquids at high pressures. The available vapor liquid equilibrium model was developed with support from previous grant from DOE-PETC (Grant no. DE-FG22-89PC90541). The current project also involves measurement of some model compound VLE data and chromatographic characterization of coal liquids for distrib… more
Date: October 1, 1991
Creator: Kabadi, V. N.
Partner: UNT Libraries Government Documents Department
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Advances in the Helium-Jet Coupled on-Line Mass Separator RAMA. [Recoil Atom Mass Analyzer]

Description: General improvements to the on-line mass separator RAMA (Recoil Atom Mass Analyzer) have yielded a greater reliability and efficiency for some elements. A new utilitarian helium-jet chamber has been installed to facilitate quick target and degrader foil changes in addition to a new ion source holder. A higher efficiency hollow-cathode, cathode-extraction ion source, for lower melting point elements (< 1200/sup 0/C) has also been designed. Tests with the beta-delayed proton emitter /sup 37/Ca… more
Date: January 1, 1980
Creator: Moltz, D. M.; Aysto, J.; Cable, M. D.; Parry, R. F.; Haustein, P. E.; Wouters, J. M. et al.
Partner: UNT Libraries Government Documents Department
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Tellurium interference in /sup 129/I activation analysis

Description: Measurement of /sup 129/I at low levels is required for effluent control, environmental assessment and tracer studies in the natural environment. Low level /sup 129/I analysis has also been used for measurement of natural-fission-produced /sup 129/I in minerals and ores as well as meteorites. The most sensitive method for /sup 129/I measurements is neutron activation analysis of iodine separated from a suitable sample. Minimum sample processing prior to neutron activation is desirable in order … more
Date: September 20, 1979
Creator: Kaye, J. H.; Brauer, F. P. & Strebin, Jr., R. S.
Partner: UNT Libraries Government Documents Department
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Multiheteromacrocycles that complex metal ions. Sixth progress report, 1 May 1979-30 April 1980. [Hemispherands; spherands]

Description: Objective is to design synthesize, and evaluate cyclic and polycyclic host organic compounds for their abilities to complex and lipophilize guest metal ions, their complexes, and their clusters. Host organic compounds consist of strategically placed solvating, coordinating, and ion-pairing sites tied together by covalent bonds through hydrocarbon units around cavities shaped to be occupied by guest metal ions or by metal ions plus their ligands. Specificity in complexation is sought by matching… more
Date: January 15, 1980
Creator: Cram, D. J.
Partner: UNT Libraries Government Documents Department
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Price 1/sup 0/ x 2/sup 0/ NTMS area, Utah. Data report (abbreviated)

Description: Surface sediment samples were collected at 1444 sites, at a target sampling density of one site per 13 square kilometers. Ground water samples were collected at 137 sites. Neutron activation analysis results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water. Mass spectrometry results are given for helium in ground water. Field measurements and observations are reported for each site. Analytical data and field measurements are presente… more
Date: July 1, 1980
Creator: Cook, J. R.
Partner: UNT Libraries Government Documents Department
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Gas chromatographic studies of the relative retention of the sulfur isotopes in carbonyl sulfide, carbon disulfide, and sulfur dioxide

Description: A precision gas chromatograph, coupled to a quadrupole mass spectrometer and an on-line computer, was used to study the fractionation on Porasil A of the /sup 32/S//sup 34/S isotopic pair in a variety of sulfur-containing molecules. Carbonyl sulfide (COS) yielded an average ..cap alpha.. value of 1.00074 +- 0.00017 (standard deviation) for the temperature range 25/sup 0/C to 75/sup 0/C. The carbon disulfide (CS/sub 2/) value was 1.00069 +- 0.00023 for the range 53/sup 0/C to 103/sup 0/C, and th… more
Date: January 18, 1980
Creator: Fetzer, J.C. & Rogers, L.B.
Partner: UNT Libraries Government Documents Department
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Thermodynamics of natural and industrial waters

Description: The most effective general formulations of thermodynamic equations for multicomponent aqueous solutions are discussed with respect to various ranges of temperature, pressure and composition with emphasis on solutes important in natural or industrial waters. A familiar equation in molality and in excess Gibbs energy is very successful up to 300{degree}C and ionic strength 6 mol{center dot}kg{sup {minus}1}, and can often be extended to 350{degree}C or above at high pressure and in favorable cases… more
Date: August 1, 1991
Creator: Pitzer, K.S.
Partner: UNT Libraries Government Documents Department
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Thermophysical properties of argon

Description: The entire report consists of tables of thermodynamic properties (including sound velocity, thermal conductivity and diffusivity, Prandtl number, density) of argon at 86 to 400/degree/K, in the form of isobars over 0.9 to 100 bars. (DLC)
Date: February 1, 1988
Creator: Jaques, A.
Partner: UNT Libraries Government Documents Department
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Theory of chemical kinetics. Progress report, May 1, 1977--January 15, 1978. [Massachusetts Inst. of Tech. , Cambridge]

Description: Recent work on Franck--Condon factors in studies of the dynamics of chemical reactions is related; emphasis was on simple chemical rearrangement reactions. Other work concerned collision-free unimolecular decomposition of large molecules at a given total energy, equations of motion for simple quantum systems that are strongly driven by an external field and are modulated stochastically by a coupling to a bath, and the efficiency of rate processes in irreversible chemical reactions. This report … more
Date: unknown
Creator: Ross, J.
Partner: UNT Libraries Government Documents Department
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Radiochemical analyses of samples from beneath a solid radioactive waste disposal pit at Los Alamos, New Mexico

Description: Solid radioactive wastes are disposed of by burial in pits excavated in rhyolite tuff at the Los Alamos Scientific Laboratory (LASL). Contaminants in the waste include fission products, uranium, and transuranic elements. In 1976, horizontal core holes were drilled beneath a waste disposal pit that was used from 1963 to 1966. Samples of the core were analyzed for gross alpha, gross beta, total uranium, /sup 90/Sr, /sup 137/Cs, /sup 238/Pu, /sup 239/ /sup 240/Pu, and /sup 241/Am. The measured gro… more
Date: June 1, 1980
Creator: Purtymun, W. D.; Rogers, M. A. & Wheeler, M. L.
Partner: UNT Libraries Government Documents Department
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Vapor phase spectroscopy of complex lanthanide halide--aluminum halide molecular species

Description: The absorption spectrum of ErCl/sub 3/ (AlCl/sub 3/)/sub x/ vapor complex was measured and analyzed using the Judd-Ofelt theory. Structural correlations in other AlCl/sub 3/ vapor complexes and radiation emission are discussed. Fluorescence of TbCl/sub 3/ (AlCl/sub 3/)/sub x/ vapor complex and in the NdCl/sub 3/ (AlCl/sub 3/)/sub x/ system were studied. (DLC)
Date: January 1, 1977
Creator: Carnall, W T; Hessler, J P; Williams, C W & Hoekstra, H R
Partner: UNT Libraries Government Documents Department
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Complex temporal and spatial patterns in nonequilibrium systems

Description: Dynamical systems methods are being developed and used to characterize the formation and evolution of temporal and spatial patterns in systems maintained far from equilibrium. In particular, experiments and analyses are considering electrodeposition of fractal metallic clusters, pattern formation in reaction-diffusion systems, and the primary instabilities of some fluid flows. Novel reactors have been developed to search for chemical patterns (spatial variations in the chemical composition), an… more
Date: September 1, 1991
Creator: Swinney, H. L.
Partner: UNT Libraries Government Documents Department
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