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Division of Energy Biosciences annual report and summaries of FY 1991 activities

Description: As a component of the Department of Energy, the Energy Biosciences (EB) program of the Office of Basic Energy Sciences supports long-term research aimed at addressing energy-related problems utilizing biological systems. There are three main components of the EB program. The first, Primary Biological Energy Conversion, concentrates on research on plant and microbial photosynthesis, but also deals with plant growth control, stress reactions, and interaction with pathogens. The second, Bioconvers… more
Date: September 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Summary of the LLNL one-dimensional transport-kinetics model of the troposphere and stratosphere: 1981

Description: Since the LLNL one-dimensional coupled transport and chemical kinetics model of the troposphere and stratosphere was originally developed in 1972 (Chang et al., 1974), there have been many changes to the model's representation of atmospheric physical and chemical processes. A brief description is given of the current LLNL one-dimensional coupled transport and chemical kinetics model of the troposphere and stratosphere.
Date: September 1, 1981
Creator: Wuebbles, D.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies relevant to the catalytic activation of carbon monoxide

Description: Research activity has included continued mechanistic investigations of the nucleophilic activation of carbon monoxide such as homogeneous catalysis of the water gas shift and key steps in the relevant catalytic cycles. Other investigations of related processes included the application of fast reaction techniques to prepare and to investigate quantitatively reactive organometallic intermediates relevant to the activation of hydrocarbons toward carbonylation and other functionalizations. 8 refs.
Date: September 4, 1991
Creator: Ford, P.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Toxic organic compounds from energy production

Description: The US Department of Energy's Office of Health and Environmental Research (OHER) has supported work in our laboratory since 1977. The general theme of this program has been the identification of potentially toxic organic compounds associated with various combustion effluents, following the fates of these compounds in the environment, and improving the analytical methodology for making these measurements. The projects currently investigation include: an improved sampler for semi-volatile compoun… more
Date: September 20, 1991
Creator: Hites, R.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photofragment imaging: The photo-dissociation of bromomethane, bromoethane, and bromoethanol

Description: Bromomethane, bromoethane and bromoethanol are photolyzed with 205-nm light and the velocity of the bromine atoms is recorded by the technique of photofragment imaging. The velocity distribution of the bromine atoms is a direct reflection of the internal-state distribution of the methyl, ethyl, and hydroxy-ethyl radicals and the orientation of the transition moment in the parent molecule. 8 refs., 2 figs., 1 tab.
Date: September 1, 1990
Creator: Chandler, D.W. (Sandia National Labs., Albuquerque, NM (United States)); Thoman, J.W. Jr. (Williams Coll., Williamstown, MA (United States). Dept. of Chemistry) & Hess, W.P. (Battelle Pacific Northwest Lab., Richland, WA (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reactions of metal ions and their clusters in the gas phase using laser ionization--Fourier transform mass spectrometry

Description: Carbon clusters of the form C{sub N}{sup {minus}} are observed at least out to N = 30 confirming that cluster formation is occurring in the high pressure waiting room'' of the supersonic cluster source. This can be stated unequivocally, since only up to N = 13 is observed by direct laser desorption of a carbon target in the absence of supersonic expansion. Currently underway is a systematic investigation of a wide variety of M{sup +}-C{sub n}H{sub 2n} species with n = 2--10 and M = first and se… more
Date: September 1, 1990
Creator: Freiser, B.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Research overview of biological and chemical conversion methods and identification of key research areas for SERI. Final task report

Description: A qualitative overview of the current and future research areas of the Biological and Chemical Conversion Branch is presented. The goals of the Branch and the general areas of Branch activities are mapped out: energy and petrochemical substitutes from biomass, thermochemical conversion, and photoconversion. Each of these three areas in some detail are discussed in some detail in a general overview. Specific parts of the three major areas which have been selected are discussed in the context of … more
Date: September 1, 1978
Creator: Milne, T. A.; Connolly, J. S.; Inman, R. E.; Reed, T. B. & Seibert, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical Biodynamics Division: Annual report, October 1, 1986-September 30, 1987

Description: Investigators are studying the various components that make up the photosynthetic reaction center complexes in many different organisms. This work not only involves understanding the kinetics of energy transfer and storage in plants, but also includes studies to work out how photosynthetic cells regulate the expression of genes encoding the photosynthetic apparatus. The second biological theme is a series of investigations into the relationship between structure and function in nucleic acids. O… more
Date: September 1, 1987
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Structural relationship in chloroplast membranes. Final report, August 1, 1977-August 31, 1980

Description: Methodology has been developed for the isolation and characterization of pigment-proteins from chloroplast membranes. Characterization of these pigment-proteins has increased our understanding of mechanisms regulating the efficiency of photosynthetic light harvesting during photosynthesis. Incorporation of isolated pigment-protein complexes into model membranes has allowed simulation of grana stacks; these structural features of chloroplasts play a key role in maintaining appropriate interactio… more
Date: September 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrogen and methane synthesis through radiation catalysis. Final report

Description: The goal of this research was to evaluate the potential for using reactor wastes to synthesize useful products in quasi-photochemical configuration. It was found that semiconductor oxides act as heterogenous catalysts for the formation of H/sub 2/ in aqueous media under /sup 60/Co irradiation. The principle of a gamma-ray solar cell was demonstrated experimentally. Experiments with ultraviolet irradiated TiO/sub 2/ and ZnO grains demonstrated that both H/sub 2/ and H/sub 2/O/sub 2/ were formed,… more
Date: September 1, 1980
Creator: DuBow, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photophysics and photoredox processes at liquid-liquid interfaces

Description: This report is divided into four sections: (1) Recent work on polymers with covalently bound chromophores, primarily involving triplet state electron transfer quenching; (2) Pyrene and pyrene butyric acid adsorbed onto polystyrene latexes (microspheres); (3) Adsorption and micellization of amphiphilic block polymers with chromophores at the junction between the hydrophobic and hydrophilic part; (4) Adsorption of alternating polymers with grafted combs'' to improve adsorption onto a hydrophobic … more
Date: September 1, 1992
Creator: Webber, S.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Crossed Laser and Molecular Beam Study of Multiphoton Dissociation of C/sub 2/F/sub 5/Cl

Description: Rate constants for the photodissociation of C/sub 2/F/sub 5/Cl as well as the yield of C/sub 2/F/sub 4//sup +/ were measured. The dynamics of the two dissociation channels was studied by measuring the angular and velocity distributions of the products. 2 references. (JFP)
Date: September 1, 1978
Creator: Krajnovich, D.J.; Giardini-Guidoni, A.; Sudboe, A.S.; Schulz, P.A.; Shen, Y.R. & Lee, Y.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Pulsed laser kinetic studies of liquids under high pressure

Description: A laser flash photolysis kinetic study of 2,2{prime}-bipyridine bidentate chelating ligands with one claw in the first coordination sphere of a molybdenum carbonyl complex has been completed at pressures up to 150 MPa. The reaction mechanism for thermal ring closure is found from activation volumes to change from associative interchange to dissociative interchange as substituents on the 2,2{prime}-bipyridine ligands become bulkier. In a similar study of more rigid, substituted phenanthroline bi… more
Date: September 22, 1992
Creator: Eyring, E.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of a practical photochemical energy storage system. Quarterly report, July 1, 1977--September 30, 1977

Description: During this quarter the portion of this project concerned with catalysis has concentrated on the development of increased understanding of the cobalt(II) porphyrin catalyst. Of potential importance is the observation that the activity of partially deactivated catalysts can be partially restored by treatment with titanium(III) solutions thereby suggesting that a major cause of the losses of activity of catalysts upon repeated recycling arises from oxidation of cobalt(II) to cobalt(III). The prev… more
Date: September 15, 1977
Creator: Hautala, R.R. & Kutal, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ESR studies of surface adsorption and catalysis under ultra-high vacuum conditions. Progress report, March 1, 1982-February 28, 1983

Description: A study was conducted of the new phenomenon of surface-suppressed ESR (SSESR), in which stable paramagnetic radicals adsorbed on clean Ag or Cu surfaces have their ESR signal suppressed until several layers of molecules insulate subsequent layers from the metal surface. This study combined UHV-ESR, CREMSEE, and thermal desorption. A tentative model based upon transmission of the effects of the surface conduction band of the metal by the weak exchange forces between the paramagnetic species was … more
Date: September 1, 1982
Creator: Freed, J. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling study of vibrational photochemical isotope enrichment. [HBr + Cl/sub 2/; HCl + Br/sub 2/]

Description: Chemical kinetic modeling studies of vibrational-photochemical isotope enrichment have been performed on two systems: Model (I), H/sup 79/Br(H/sup 81/Br) + Cl/sub 2/ and, Model (II), H/sup 37/Cl(H/sup 35/Cl) + Br. Pulsed laser excitation was modeled to the first excited vibrational level of H/sup 79/Br in Model I and the first and second excited vibrational levels of both HCl isotopes in Model II. These are prototype systems of exoergic (Model I) and endoergic (Model II) reactions. The effects … more
Date: September 29, 1978
Creator: Badcock, C.C.; Hwang, W.C. & Kalsch, J.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Formation of gas-phase peroxides in a rural atmosphere: An interpretation of the recent SOS/SERON field results

Description: Hydrogen perioxide (H{sub 2}O{sub 2}) and certain organic peroxides such as hydroxymethyl-hydroperoxide (HMHP), are gas-phase oxidants present in the atmosphere at ppbv concentration levels. These oxidants play an important role in atmospheric chemistry. In addition, precipitation containing H{sub 2}O{sub 2} is toxic to trees, and it has also been suggested that organic peroxides formed presumably by ozone reactions with biogenic alkenes are responsible for leaf disorders. Recently, we have dev… more
Date: September 1, 1993
Creator: Lee, J. H.; Tang, I. N. & Weinstein-Lloyd, J. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vibrational dynamics in photoinduced electron transfer. Progress report, December 1, 1992--November 30, 1993

Description: Objective is to perform a new type of measurement for optically excited electron transfer processes that can provide unique experimental insight into the molecular mechanism of electron transfer. Measurements of optically excited electron transfer are done with picosecond infrared (IR) absorption spectroscopy to monitor the vibrational motions of the molecules immediately after electron transfer. Theory and experiment suggest that molecular vibrations and distortions are important controlling e… more
Date: September 8, 1993
Creator: Spears, K. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photochemical dynamics of surface oriented molecules. Progress report, August 1, 1991--July 31, 1992

Description: The period 8/01/91-7/31/92 is the first year of a new project titled ``Photochemical Dynamics of Surface Oriented Molecules``, initiated with DOE Support. The main objective of this project is to understand the dynamics of elementary chemical reactions by studying photochemical dynamics of surface-oriented molecules. In addition, the mechanisms of photon-surface interactions need to be elucidated. The strategy is to carry out experiments to measure the translational energy distribution, as a fu… more
Date: September 1, 1992
Creator: Ho, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pulsed laser kinetic studies of liquids under high pressure. Progress report, November 25, 1991--September 18, 1992

Description: A laser flash photolysis kinetic study of 2,2{prime}-bipyridine bidentate chelating ligands with one claw in the first coordination sphere of a molybdenum carbonyl complex has been completed at pressures up to 150 MPa. The reaction mechanism for thermal ring closure is found from activation volumes to change from associative interchange to dissociative interchange as substituents on the 2,2{prime}-bipyridine ligands become bulkier. In a similar study of more rigid, substituted phenanthroline bi… more
Date: September 22, 1992
Creator: Eyring, E. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Energy exchange within ecosystems. Fifth annual technical progress report, January 1--December 31, 1976. [Elodea densa]

Description: During the past year we have studied the effect of pH and inorganic carbon concentration on the photosynthesis of Elodea densa. In the pH range of 6 to 9, there is a dramatic change in the response of photosynthesis to pH. At 1 mM inorganic carbon and below photosynthesis increases with decreasing pH as expected, but at 10 mM and above there is a peak. This peak is between pH 7.5 and 8.0 when the inorganic carbon concentration is 10 to 20 mM and shifts to lower pH's with increasing temperature … more
Date: September 21, 1976
Creator: Gates, D. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photochemical charge separation in zeolites: Electron transfer dynamics, nanocrystals and zeolitic membranes. Final technical report

Description: Aluminosilicate zeolites provide an excellent host for photochemical charge separation. Because of the constraints provided by the zeolite, the back electron transfer from the reduced acceptor to the oxidized sensitizer is slowed down. This provides the opportunity to separate the charge and use it in a subsequent reaction for water oxidation and reduction. Zeolite-based ruthenium oxide catalysts have been found to be efficient for the water splitting process. This project has demonstrated the … more
Date: September 30, 2001
Creator: Dutta, Prabir K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cationically polymerizable monomers derived from renewable sources. Final report

Description: Objective is to use products from plant sources as monomers for direct production of polymers for plastic applications. (Epoxidized triglycerides as renewable monomers in photoinitiated cationic polymerization.) High-volume American agricultural products such as soybean, cotton or linseed oils or forestry products such as lignin and cellulose derived chemicals were targeted for use either directly or with slight modification for producing the plastics. Cationic photopolymerization will be used.
Date: September 1, 1995
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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