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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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Drug metabolizing enzyme systems and their relationship to toxic mechanisms

Description: The metabolism and toxicity of 3-methylfuran (3-MF) are described. The major product of metabolic activation of 3-MF appears to be disemicarbazones. Cursory description of toxic effects of 3-MF on lung and kidneys are provided. 18 refs.
Date: January 1, 1983
Creator: Boyd, M. R.; Ravindranath, V.; Burka, L. T.; Dutcher, J. S.; Franklin, R. B.; Statham, C. N. et al.
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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Hydrogen bonding in asphaltenes and coal. Progress report, March 1, 1977--August 31, 1977

Description: A calorimetric method is presented for the simultaneous evaluation of equilibrium constant, K, and molar enthalpy, ..delta..H/sup 0/, for 1 : 1 adduct formation of quinoline (Qu) with asphaltene (A), together with its acid/neutral (AA) fraction and its base (BA) fraction, isolated from a centrifuged liquid product (CLP) sample prepared from Kentucky hvAb coal at 27.6 MPa hydrogen pressure and 723K, with reactor charged with glass pellets. The same procedure was used to determine K and ..delta..… more
Date: August 1, 1977
Creator: Li, N. C. & Tewari, K. C.
Partner: UNT Libraries Government Documents Department
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Excited-state proton-transfer kinetics in 1-naphthol, 1-naphthol-sulfonates, and organometallic complexes

Description: The dissociation of 1-naphthol in aqueous solution occurs so rapidly that the fluorescence from the neutral form, ROH, has been previously described as completely extinguished or hardly noticeable. Apparently nearly all of the fluorescence originates from the naphtholate ion. This paper reports on the proton-transfer characteristics of a series of 1-naphthol compounds, and also reports preliminary data on excited-state proton transfer in an organometallic complex of ruthenium.
Date: July 1, 1980
Creator: Shapiro, S. L.; Winn, K. R. & Clark, J. H.
Partner: UNT Libraries Government Documents Department
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Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

Description: This report describes progress on research during the eleventh quarter of this contract dealing with applications of coal pretreatment techniques in coal/oil co-processing and direct hydroliquefaction. The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal convers… more
Date: 1991-06~
Creator: Baldwin, R. M.; Gaur, S. & Miller, R. L.
Partner: UNT Libraries Government Documents Department
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Damage to fused silica windows while under simultaneous exposure to flowing solvents and laser radiation and 308nm

Description: This paper reports the results of a study to determine the degrading effects of flowing dye solvents on the laser damage threshold of fused-silica windows at 308nm. Thresholds were measured at the SiO/sub 2/solvent interface in a test cell. Bare SiO/sub 2/ tested in air at 308nm (20ns) typically exhibits a threshold ranging from 4 to 10 Jcm/sup 2/; with the solvent cyclohexane in contact, a threshold as low as 0.3 Jcm/sup 2/ was measured. The damage data indicate that window lifetime (number of… more
Date: January 1, 1987
Creator: Mauro, B. R.; Foltyn, S. R. & Sanders, V. E.
Partner: UNT Libraries Government Documents Department
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Steroselective synthesis and application of L-( sup 15 N) amino acids

Description: We have developed two general approaches to the stereoselective synthesis of {sup 15}N- and {sup 13}C-labeled amino acids. First, labeled serine, biosynthesized using the methylotrophic bacterium M. extorquens AM1, serves as a chiral precursor for the synthesis of other amino acids. For example, pyridoxal phosphate enzymes can be used for the conversion of L-({alpha}-{sup 15}N)serine to L-({alpha}-{sup 15}N)tyrosine, L-({alpha}-{sup 15}N)tryptophan, and L-({alpha}-{sup 15}N)cysteine. In the sec… more
Date: January 1, 1991
Creator: Unkefer, C.J. (Los Alamos National Lab., NM (United States)) & Lodwig, S.N. (Centralia Coll., WA (United States). Div. of Science)
Partner: UNT Libraries Government Documents Department
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The magnesium chelation step in chlorophyll biosynthesis

Description: The biogenesis of energy transducing membranes requires the coordinate synthesis of prosthetic groups, proteins and lipids. Two of the major prosthetic groups, chlorophyll and heme, share a common biosynthetic pathway that diverges at the point of metal insertion into protoporphyrin IX. Insertion of iron leads to heme, while insertion of magnesium leads to chlorophyll. The Mg-chelatase from intact cucumber chloroplasts has been characterized with regard to substrate specificity, regulation, ATP… more
Date: January 1, 1991
Creator: Weinstein, J.D.
Partner: UNT Libraries Government Documents Department
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Mechanisms for radiation damage in DNA. Progress report, January 1, 1982-December 31, 1982

Description: In this project several mechanisms are proposed for radiation damage to DNA constituents and DNA, and a series of experiments utilizing electron spin resonance spectrometry to test the proposed mechanisms have been detailed. In the past studies have concentrated chiefly on the direct effect of radiation on DNA. We are currently investigating irradiated systems of DNA constituents which may shed light on indirect effects. In addition, studies of radiation effects on lipids have been undertaken w… more
Date: May 1, 1982
Creator: Sevilla, M. D.
Partner: UNT Libraries Government Documents Department
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Heavy recycle solvent studies in two-stage coal liquefaction. Final technical report, September 1, 1982-December 30, 1983

Description: The objective of this program has been to study the chemistry of the components with high boiling points in a direct coal liquefaction recycle solvent and to identify those components which lead to higher overall yields and improved product stability in the initial coal dissolution step of direct coal liquefaction processes. The major conclusions are: -454 C recycle solvent is primarily aromatic hydrocarbons (73%) and contains almost no asphaltenes; +454 C recycle solvent is primarily asphalten… more
Date: January 10, 1984
Creator: Longanbach, J. R.
Partner: UNT Libraries Government Documents Department
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Excision repair of bulky lesions in the DNA of mammalian cells

Description: The report examines the process of excision repair of pyrimidine dimers from uv-irradiated and chemically challenged human cells. It is shown by means of a sensitive endonuclease assay that the amount of excision observed depends upon the isotope used to label cells, and that XP heterozygotes are between normals and XPs. (ACR)
Date: January 1, 1980
Creator: Setlow, R B & Grist, E
Partner: UNT Libraries Government Documents Department
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Removal of uv-induced pyrimidine dimers from the replicated and unreplicated DNA of human fibroblasts

Description: Excision repair in uv irradiated human fibroblasts has been examined in portions of DNA replicating after irradiation versus those remaining unreplicated. Two approaches, one using a uv-endonuclease to estimate pyrimidine dimers remaining in DNA, the other using density labeling to measure excision resynthesis, indicate that the extent of repair is the same for both replicated and unreplicated DNA.
Date: January 1, 1978
Creator: Waters, R.
Partner: UNT Libraries Government Documents Department
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Volatilities of ruthenium, iodine, and technetium on calcining fission product nitrate wastes

Description: Various high-level nitrate wastes were subjected to formic acid denitration. Formic acid reacts with the nitrate anion to yield noncondensable, inert gases according to the following equation: 4 HCOOH + 2 HNO/sub 3/ ..-->.. N/sub 2/O + 4 CO/sub 2/ + 5 H/sub 2/O. These gases can be scrubbed free of /sup 106/Ru, /sup 131/I, and /sup 99/Tc radioactivities prior to elimination from the plant by passage through HEPA filters. The formation of deleterious NO/sub x/ is avoided. Moreover, formic acid re… more
Date: January 1, 1980
Creator: Rimshaw, S. J. & Case, F. N.
Partner: UNT Libraries Government Documents Department
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Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, October 1, 1979-September 30, 1980. [Ethane Elimination]

Description: The 1,1-reductive elimination of ethane from three cis-bis(phosphine)-dimethylpalladium complexes, L/sub 2/Pd(CH/sub 3/)/sub 2/ (L = PPh/sub 3/, PPh/sub 2/,CH/sub 3/ and L/sub 2/ = Ph/sub 2/PCH/sub 2/CH/sub 2/PPh/sub 2/), and three trans analogs (L = PPh/sub 3/, PPh/sub 2/CH/sub 3/ and L/sub 2/ = 2,11-bis(diphenylphosphinomethyl)benzo(c)phenanthrene (TRANSPHOS)) was carried out. The three cis complexes underwent reductive elimination in the presence of coordinating solvents (DMSO, DMF, and THF)… more
Date: September 1, 1980
Creator: Stille, J. K.
Partner: UNT Libraries Government Documents Department
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Thermodynamics of the hydrodenitrogenation of carbazole

Description: A thermodynamic analysis, based on accurate experimental Gibbs energies of formation, was completed for the key hydrogen-consuming steps in the HDN reaction network for carbazole. The results were compared with literature reaction studies. The concept of crossover temperature'' is shown to be a valuable tool in the interpretation of literature reaction-study results. Methods of nitrogen removal from aromatic materials are discussed in light of the findings of the thermodynamic analysis. It is c… more
Date: October 1, 1991
Creator: Steele, W. V. & Chirico, R. D.
Partner: UNT Libraries Government Documents Department
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Molecular biological enhancement of coal biodesulfurization. [Rhodococcus, thiobacillus]

Description: The objective of this project is to produce one or more microorganisms capable of removing the organic and inorganic sulfur in coal. The original specific technical objectives of the project were to: clone and characterize the genes encoding the enzymes of the 4S'' pathway (sulfoxide/sulfone/sulfonate/sulfate) for release of organic sulfur from coal; return multiple copies of genes to the original host to enhance the biodesulfurization activity of that organism; transfer this pathway into a fas… more
Date: June 14, 1990
Creator: Litchfield, J. H.; Fry, I.; Wyza, R. E.; Palmer, D. T.; Zupancic, T. J. & Conkle, H. N.
Partner: UNT Libraries Government Documents Department
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Control of catalytic hydrotreating selectivity with ammonia. [Hydrodeoxygenation]

Description: The hydrogenation of naphthalene in the presence of 0, 24, or 48 kPa of ammonia derived from propyl amine was studied during the hydrodeoxygenation (HDO) of dibenzofuran (DBF). A new sample of sulfided NiMo/Al{sub 2}O{sub 3} catalyst at 360{degrees}C, 6.9 MPa total H{sub 2} pressure in a vapor phase tubular reactor was used. As a base-line the HDO of DBF was also studied in the absence of both naphthalene and ammonia. Ammonia inhibited both the HDO of dibenzofuran and the hydrogenation of napht… more
Date: January 1, 1992
Creator: Satterfield, C. N. & Lee, C. M.
Partner: UNT Libraries Government Documents Department
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Superacid Catalyzed Coal Conversion Chemistry. 1st and 2nd Quarterly Technical Progress Reports, September 1, 1983-March 30, 1984. [Model Compound Consisting of 2 Benzene Rings Connected With Various Bridging Units Such as Alkylidene, Ether, Sulfide, Etc]

Description: In our laboratories we have previously developed a mild coal conversion process. This involves the use of a superacid system consisting of HF and BF/sub 3/ in presence of hydrogen and/or a hydrogen donor solvent. In order to understand the chemistry involved in the process of depolymerization of coal by the HF:BF/sub 3/:H/sub 2/ system we are carrying out a systematic study of a number of coal model compounds. The model compounds selected for present study have two benzene rings connected with … more
Date: January 1, 1984
Creator: Olah, G.A.
Partner: UNT Libraries Government Documents Department
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Enthalpy measurement of coal-derived liquids. Quarterly technical progress report, July-September 1980

Description: Equipment modifications to a Freon 11 boil-off type calorimeter are described. The calorimetric system was used to measure the enthalpies of thiophene experimentally. Data were taken over a temperature range of 100/sup 0/F to 750/sup 0/F at pressures of 50, 100, 200, 400, 600, 825.9 (the critical), 1000, and 1500 psia. Thermodynamic properties derived from the data are compared to values in the literature, and the agreement is exceptionally good. The data are then compared directly to results c… more
Date: September 15, 1980
Creator: Kidnay, A. J. & Yesavage, V. F.
Partner: UNT Libraries Government Documents Department
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Characterization of nitrogen compound types in hydrotreated Paraho shale oil

Description: Results from the separation and characterization of nitrogen compound types in hydrotreated Paraho shale oil samples were obtained. Two samples of Paraho shale oil were hydrotreated by Chevron Research Company such that one sample contained about 0.05 wt. percent nitrogen and the other sample contained about 0.10 wt. percent nitrogen. A separation method concentrate specific nitrogen compound types was developed. Characterization of the nitrogen types was accomplished by infrared spectroscopy, … more
Date: October 1, 1980
Creator: Holmes, S.A. & Latham, D.R.
Partner: UNT Libraries Government Documents Department
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Interdisciplinary research and training program in the plant sciences

Description: This document is the compiled progress reports from the Interdisciplinary Research and Training Program in the Plant Sciences funded through the MSU-DOE Plant Research Laboratory. Fourteen reports are included, covering topics such as the molecular basis of plant/microbe symbiosis, cell wall proteins and assembly, gene expression, stress responses, growth regulator biosynthesis, interaction between nuclear and organelle genomes, sensory transduction and tropisms, intracellular sorting and membr… more
Date: January 1, 1991
Creator: Wolk, C.P.
Partner: UNT Libraries Government Documents Department
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Vectorially photoinduced electron-transfer processes across water-in-oil interfaces of microemulsions

Description: Artificial photosynthetic devices are potential fuel sources. The basic idea in the design of such devices is a photosensitized electron-transfer that yields chemical species capable of reducing and oxidizing water to hydrogen and oxygen. A fundamental difficulty in effecting this transfer is the thermodynamically favored back reactions of the intermediary redox species. An interfacial model composed of a water-in-oil microemulsion is suggested to provide the separation of these redox species, … more
Date: July 1, 1980
Creator: Willner, I.; Otvos, J. W. & Calvin, M.
Partner: UNT Libraries Government Documents Department
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