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Anchoring strategies for bimetallic species in zeolites. Progress report

Description: We explore a new approach by introducing heterobinuclear organometallic compounds for linking catalytic functions to zeolite frameworks. With two different metals present, the complexes are being anchored to the support via one oxophilic metal, ligand exchange and catalytic reactions may proceed at the second metal center. Anchoring chemistry, thermal stability and reactivity of Me{sub 3}SnMn(CO){sub 5} in zeolite NaY and acid forms of zeolite Y was studied with X-ray absorption spectroscopy (S… more
Date: March 1, 1993
Creator: Bein, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalytic hydrocarbon reactions over supported metals. Progress report, February 1, 1992--March 31, 1993

Description: During the past year we have completed our characterization of the factors that control the structure of fully oxidized W and Mo on silica and have established that support hydroxyl groups play a central role in dispersing and attaching cations to the support oxide. Work with M{sub 2}(CO){sub 4}Cp{sub 2}(M{sub 2}=MoMo, WW, MoW) system has been very encouraging and continues to support the notion that it may be possible to control the structure of adsorbed catalysts (in this case generate metal … more
Date: March 29, 1993
Creator: Ekerdt, J. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low temperature, sulfur tolerant homogeneous catalysts for the water-gas shift reaction. Task 1, Topical report No. 1

Description: The purpose of this report is to update and reorganize our recent review on homogeneous catalysis of the water-gas shift reaction (WGSR) based on recent literature publications and patents. This updated version will serve as a means of selecting 10 candidate catalyst systems for use in developing effective, sulfur-tolerant, low temperature WGSR catalysts. This report discusses the variations possible in the basic chemistry associated with WGSR catalytic cycles, including basic, acidic, and neut… more
Date: January 20, 1986
Creator: Laine, R. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optically driven surface reactions: Laser probes of surface dynamics. Progress report

Description: The author`s study of the dynamics of photodesorption of NO from Si(111) 7x7 under conditions of low NO coverage has been completed. The final results are discussed herein. In addition, studies of the photodecomposition of Mo(CO){sub 6} absorbed on Si(111) have been initiated. Preliminary results and future studies are outlined.
Date: July 1, 1994
Creator: Cavanagh, R. R. & King, D. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Organic carbonyl compounds in Albuquerque, New Mexico, air: A preliminary study of the effects of oxygenated fuel use

Description: A suite of inorganic and organic species were analyzed for four 2--4 day time periods over a year in Albuquerque, New Mexico to determine baseline conditions for organic pollutants under the current air pollution control parameters. Concentrations of low molecular weight carbonyl compounds were relatively high compared with areas such as Los Angeles. Formio acid concentrations in air samples were significant even in winter. In addition, ratios of peroxypropionyl nitrate to peroxyacyetyl nitrate… more
Date: June 1, 1993
Creator: Popp, C. J.; Zhang, Lin & Gaffney, J. S.
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. 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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Catalyst dispersion and activity under conditions of temperature- staged liquefaction. Technical progress report, January--March 1992

Description: Two coals, a Texas subbituminous C and a Utah high volatile A bituminous, were used to examine the effects of solvent swelling and catalyst impregnation on liquefaction conversion behavior in temperature staged reactions for 30 minutes each at 275{degree} and 425{degree}C in H{sub 2} and 95:5 H{sub 2}:H{sub 2}S atmospheres. Methanol, pyridine, tetrahydrofuran, and tetrabutylammonium hydroxide were used as swelling agents. Molybdenum-based catalyst precursors were ammonium tetrathiomolybdate, mo… more
Date: July 1992
Creator: Davis, Alan; Schobert, H. H.; Mitchell, G. D. & Artok, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal technology program. Progress report, October 1976

Description: In the hydrocarbonization/residue carbonization work, run HC-8 was completed with the 20-atm bench-scale hydrocarbonizer in a recirculating fluidized bed mode. Runs RC-15 and RC-16 in the 1-atm residue carbonizer showed very encouraging results--it appears that the system may be sufficiently operable for material balance experiments to begin. In engineering support of in-situ gasification, a two-dimensional pyrolysis gas production mechanism assumed to explain data obtained with as-received coa… more
Date: December 1, 1976
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal Technology Program progress report, August 1976

Description: The first experiment utilizing the hydrocarbonization reactor in a recirculating fluidized bed mode was completed successfully. A residue carbonization experiment was completed in which there was no significant agglomeration in the fluidized bed reactor, but which was terminated prematurely because of a plug in the off-gas line. The characterization and settling tests of oils derived from the SRC process were continued. High-temperature coal block pyrolysis studies were completed to fill out a … more
Date: October 1, 1976
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of Coupled Chemical and Catalytic Coal Conversion Methods

Description: This report concerns our research on base-catalyzed coal solubilization and a new approach for hydrogen addition. The work on base-catalyzed, chemical solubilization is continuing. this report is focused on the hydrogenation research. Specifically it deals with the use of arene chromium carbonyl complexes as reagents for the addition of dideuterium to coal molecules. In one phase of the work, he has established that the aromatic hydrocarbons in a representative coal liquid can be converted in v… more
Date: January 1, 1990
Creator: Stock, L. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal technology program progress report for September 1976

Description: In the separations technology work, bench-scale filtrations using coal and char precoats were compared to standard filtrations using diatomaceous earth precoats. In both cases the filtration rates and filtrate clarities were comparable to standard values; thus, considerable economic savings are possible due to the lower cost and substitution of a material readily available, and subsequent recovery of the energy value of the coal or char precoat by gasification. The demonstrated use of the char … more
Date: November 1, 1976
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal technology program. Progress report for December 1976

Description: This report, the twenty-ninth of a series, is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal as a source of clean energy. The projects reported this month include those for coal conversion process development, materials engineering, alkali metal vapor topping cycles, a critical components test facility, engineering and support studies, process and program assistance, environmental assessment studie… more
Date: February 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Process for cleaning and removal of sulfur compounds from low Btu fuel gases. Interim report, January--March 1976

Description: It is proposed to remodel the PDU by incorporation of appropriate sub-systems to permit operation in continuous process mode. The PDU will be operated for a period of time sufficient to demonstrate process viability. It has been relocated to an inproved support facility and repaired to a state of near readiness for operation. During early pilot plant operation relatively high concentrations of COS were often found in the offgas from the scrubber. In some cases, these concentrations exceeded the… more
Date: April 1, 1976
Creator: Moore, R. H.; Ham, D. C. & Stegen, G. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Iron and nickel carbonyl formation in steel pipes and its prevention: literature survey

Description: Data were compiled on the stability and formation rates of iron and nickel carbonyls. The data demonstrate that carbonyl formation in steel pipes is governed largely by kinetics. The rate of carbonyl formation is a function of several factors: temperature, pressure, gas flow rate, gas composition, impurities in the gas, alloy composition, surface conditions, and pretreatment of the surfaces. An evaluation of techniques for detecting iron and nickel carbonyls in gases showed atomic absorption sp… more
Date: September 1, 1976
Creator: Brynestad, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of organometallic reaction mechanisms with one and two dimensional vibrational spectroscopy

Description: One and two dimensional time-resolved vibrational spectroscopy has been used to investigate the elementary reactions of several prototypical organometallic complexes in room temperature solution. The electron transfer and ligand substitution reactions of photogenerated 17-electron organometallic radicals CpW(CO){sub 3} and CpFe(CO){sub 2} have been examined with one dimensional spectroscopy on the picosecond through microsecond time-scales, revealing the importance of caging effects and odd-ele… more
Date: December 16, 2008
Creator: Cahoon, James Francis
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Catalyst dispersion and activity under conditions of temperature- staged liquefaction. [Catalyst precursors for molybdenum-based catalyst and iron-based catalyst]

Description: Two coals, a Texas subbituminous C and a Utah high volatile A bituminous, were used to examine the effects of solvent swelling and catalyst impregnation on liquefaction conversion behavior in temperature staged reactions for 30 minutes each at 275{degree} and 425{degree}C in H{sub 2} and 95:5 H{sub 2}:H{sub 2}S atmospheres. Methanol, pyridine, tetrahydrofuran, and tetrabutylammonium hydroxide were used as swelling agents. Molybdenum-based catalyst precursors were ammonium tetrathiomolybdate, mo… more
Date: July 1, 1992
Creator: Davis, A.; Schobert, H. H.; Mitchell, G. D. & Artok, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Developing Magnetorheological Finishing (MRF) Technology for the Manufacture of Large-Aperture Optics in Megajoule Class Laser Systems

Description: Over the last eight years we have been developing advanced MRF tools and techniques to manufacture meter-scale optics for use in Megajoule class laser systems. These systems call for optics having unique characteristics that can complicate their fabrication using conventional polishing methods. First, exposure to the high-power nanosecond and sub-nanosecond pulsed laser environment in the infrared (>27 J/cm{sup 2} at 1053 nm), visible (>18 J/cm{sup 2} at 527 nm), and ultraviolet (>10 J… more
Date: October 27, 2010
Creator: Menapace, J A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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[Laser flash photolysis, EPR and Raman studies of liquids at elevated pressures]

Description: The proposed research will solve a number of analytical chemical problems in solutions with measurement techniques that benefit from the use of elevated hydrostatic pressures: stopped-flow spectrophotometry (Gd[sup 3+] + L(ligand), [RuL[sub 5]H[sub 2]O][sup 2+], laser flash photolysis of Mo(CO)[sub 6] + L, flash photolysis of binuclear metalloproteins), EPR spectroscopy (Gd[sup 3+] ion-exchanged into ETS-10 and ETAS-10 molecular sieves), laser flash photolysis kinetic studies of Mo(CO)[sub 6]-2… more
Date: January 1, 1992
Creator: Eyring, E. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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[Mechanistic examination of organometallic electron transfer reactions: Annual report, 1989]

Description: Our mechanistic examination of electron transfer reactions between organometallic complexes has required data from our stopped-flow infrared spectrophotometer that was constructed in the first year. Our research on organometallic electron transfer reaction mechanisms was recognized by an invitation to the Symposium on Organometallic Reaction Mechanisms at the National ACS meeting in Miami. We have obtained a reasonable understanding of the electron transfer reactions between metal cations and a… more
Date: December 31, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Liquefaction of coals using ultra-fine particle, unsupported catalysts: In situ generation by rapid expansion of supercritical fluid solutions. Quarterly technical progress report, October 1, 1990--December 31, 1990

Description: The program objective is to generate ultra-fine catalyst particles (20 to 400 {Angstrom} in size) and quantify their potential for improving coal dissolution in the solubilization stage of two-stage catalytic-catalytic liquefaction systems. It has been shown that catalyst activity increases significantly with decreasing particle size for particle sizes in the submicron range. Ultra-fine catalyst particle generation will be accomplished using a novel two-step process. First, the severe condition… more
Date: August 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of pretreating of host oil on coprocessing. Quarterly progress report, October 1, 1992--December 31, 1992

Description: The principal objective of this research is to determine the role host petroleum-derived oils (1000{degrees}F+), as well as that of catalytically treated host oils, play when used as liquefaction solvents in coprocessing with coal. The host oils will be extensively characterized and then pretreated in a number of ways which involve catalytic reactions such as hydrogenation, hydrocracking, isomerization, and dehydrogenation. The pretreated oils win then be characterized. The effects of the host … more
Date: March 25, 1993
Creator: Wender, I. & Tierney, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalyst dispersion and activity under conditions of temperature- staged liquefaction. Technical progress report, July--September 1991

Description: The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experiment… more
Date: February 1, 1992
Creator: Davis, A.; Schobert, H. H.; Mitchell, G. D. & Artok, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Organometallic and Surface Chemistry of Mixed-Metal Systems. Progress Report, March 15, 1992--March 14, 1993

Description: Three new SO{sub 2} complexes of metal cluster compounds were prepared: [PPN][HFe{sub 3}(CO){sub 9}SO{sub 2}], and [PPN]{sub 2}[Ru{sub 3}CO{sub 9}SO{sub 2}] and [PPN]{sub 2}[Ru{sub 3}(CO){sub 7}(SO{sub 2}){sub 3}]. The x-ray structures were determined for two of these and the transformation of bound SO{sub 2} to duster bound SO and S ligands was investigated.
Date: April 1993
Creator: Shriver, D. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Highly Dispersed Catalysts for Coal Liquefaction. Quarterly Report No. 8, May 23, 1993--August 22, 1993

Description: The objectives of this project are to study the effect of pretreatment methods on the two-stage liquefaction process. In particular, the effects of dispersed catalysts and carbon monoxide atmospheres on a coal liquefaction process. The project is divided into three technical tasks. Task 1 and 2 deal with the analyses and liquefaction experiments, respectively, whereas Task 3 deals with the economic impact of utilizing the pretreatment methods. This quarter we concentrated on Tasks 1 and 2, whic… more
Date: November 1, 1993
Creator: Hirschon, Albert S. & Wilson, Robert B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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