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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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surface extended x-ray absorption fine structure of low-Z absorbates using fluorescence detection

Description: Comparison of x-ray fluorescence yield (FY) and electron yield surface extended x-ray absorption fine structure spectra above the S K-edge for c(2 x 2) S on Ni(100) reveals an order of magnitude higher sensitivity of the FY technique. Using FY detection, thiophene (C/sub 4/H/sub 4/S) chemisorption on Ni(100) is studied with S coverages down to 0.08 monolayer. The molecule dissociates at temperatures as low as 100K by interaction with fourfold hollow Ni sites. Blocking of these sites by oxygen l… more
Date: May 1, 1985
Creator: Stoehr, J.; Kollin, E.B.; Fischer, D.A.; Hastings, J.B.; Zaera, F. & Sette, F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Interactive Chemistry of Coal-Petroleum Processing

Description: The objective of this program is to investigate the interactive thermal and catalytic chemistry of coal and petroleum processing using model compounds and actual petroleum-coal materials. This quarter the interactive catalytic chemistry of model coal and petroleum systems was investigated using combined catalysts of molybdenum naphthenate and vanadyl acetylacetonate. This combination was performed in order to evaluate the effect of the presence of an indigenous residuum metal, vanadium, on mode… more
Date: January 1, 1989
Creator: Curtis, C. W.; Guin, J. A. & Tarrer, A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transition metal activation and functionalization of carbon-hydrogen bonds

Description: We are investigating the fundamental thermodynamic and kinetic factors that influence carbon-hydrogen bond activation at homogeneous transition metal centers and the conversion of hydrocarbons into functionalized products of potential use to the chemical industry. Advances have been made in both understanding the interactions of hydrocarbons with metals and in the functionalization of hydrocarbons. We have found that RhCl(PR{sub 3}){sub 2}(CNR) complexes can catalyze the insertion of isonitrile… more
Date: June 1, 1992
Creator: Jones, W.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Spin-mapping of coal structures with ESE and ENDOR

Description: Advanced EPR methods have demonstrated cability for study of molecular components (including organic sulfur) in coal. We have constructed a unique Very High Frequency Electron Paramagnetic Resonance (VHF EPR) instrument operating at the W-band (96 GHz), one of only two such instruments in the world, and the only one studying coal. We are employing this instrument, as well as collaborating with scientists at Cornell University who have constructed a 250 GHz EPR spectrometer, to develop a clearer… more
Date: March 1, 1991
Creator: Belford, R. L. & Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pre-methanation purification study: removal of low concentration gaseous sulfur compounds (catalyst poisons)

Description: Before catalytic methanation can be used for the commercial production of synthetic natural gas from synthesis gas, the problem of methanation catalyst deactivation must be solved. The nickel catalyst used is easily poisoned by sulfur compounds. It was the purpose of this program to identify and develop a viable and effective pre-methanation purification system to protect the methanation catalyst and therby promote viable coal gasification by the SYNTHANE process. A review and analysis was made… more
Date: February 1, 1978
Creator: Iaccarino, E.P.; Lieberman, M. & Taylor, W.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Theoretical Studies in Heterogenous Catalysis: Towards a Rational Design of Novel Catalysts for Hydrodesulfurization and Hydrogen Production

Description: Traditionally, knowledge in heterogeneous catalysis has come through empirical research. Nowadays, there is a clear interest to change this since millions of dollars in products are generated every year in the chemical and petrochemical industries through catalytic processes. To obtain a fundamental knowledge of the factors that determine the activity of heterogeneous catalysts is a challenge for modern science since many of these systems are very complex in nature. In principle, when a molecul… more
Date: October 1, 2008
Creator: Rodriguez,J.A. & Liu, P.
Item Type: Refine your search to only Book
Partner: UNT Libraries Government Documents Department
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Methyltrihydroborate complexes of the lanthanides and actinides

Description: Reaction of MC1/sub 4/ (M = Zr, Hf, U, Th, Np) with LiBH/sub 3/CH/sub 3/ in chlorobenzene produces volatile, hexane-soluble M(BH/sub 3/CH/sub 3/)/sub 4/. Crystal structures are monomeric, tetrahedral species. Lewis base adducts prepared include U(BH/sub 3/CH/sub 3/)/sub 4/.THT, Th(BH/sub 3/CH/sub 3/)/sub 4/.L (L = THF (tetrahydrofuran), THT (tetrahydrothiophene), SMe/sub 2/, OMe/sub 2/), U(BH/sub 3/CH/sub 3/)/sub 4/.2L (L = THF, pyridine, NH/sub 3/), Th(BH/sub 3/CH/sub 3/)/sub 4/.2L (L = THF, T… more
Date: November 1, 1984
Creator: Shinomoto, R.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Influence of fuel sulfur on the selective reduction of NO by NH/sub 3/

Description: The selective reduction of NO by NH/sub 3/ addition has been studied in a lean-burning oil fired laboratory combustion tunnel with pyridine and thiophene added to the fuel oil. Two distinct, but interrelated effects were observed. The conversion of a fixed amount of fuel nitrogen to NO in the flame increased as the fuel sulfur concentration increased. In the post-combustion gases, there was a shift in the temperature dependence of the reduction process when the sulfur combustion products were p… more
Date: October 1, 1981
Creator: Lucas, D. & Brown, N.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Differential optical absorption techniques for diagnostics of coal gasification. Technical progress report, April-June 1983

Description: The application of differential optical absorption (DOA) techniques for the in-situ determination of the chemical composition of coal gasification process streams is investigated. Absorption spectra of relevant molecular species and the temperature and pressure effects on DOA-determined spectral characteristics of these species will be determined and cataloged. A system will be configured, assembled, and tested. 10 references, 1 figure.
Date: August 1, 1983
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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VHF EPR determination of the chemical forms of organic sulfur in coal

Description: This program addresses the need for innovative approaches to characterize the organic sulfur in Illinois Basin coals. We have developed a very high frequency electron paramagnetic resonance (EPR) spectrometer operating at the W-band of microwave frequencies (96 GHz). This instrument has shown unique sensitivity to heteroatoms in coal, and we believe the technique can be successfully applied for the non-destructive, direct determination of organic sulfur in coal. Preliminary data from Illinois c… more
Date: January 1, 1991
Creator: Clarkson, R.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Desulfurization of coal model compounds and coal liquids.

Description: Most US coals contain sulfur concentrations that prevent their being burned without some form of sulfur removal. Current coal-cleaning technology can only remove the fairly reactive pyritic (inorganic) and aliphatic (organic) sulfur. A process which removes the more refractory hetero-aromatic sulfur could substantially increase the amount of coal reserves amenable to chemical cleaning. Sodium metal dispersions convert refractor model compounds into lighter desulfurized products and non-volatile… more
Date: April 1, 1979
Creator: Wrathall, James Anthony & Peterson, Eugene E.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Thermodynamic properties for polycyclic systems by non-calorimetric methods

Description: A detailed vibrational spectroscopic study of furan, pyrrole, and thiophene has been completed. These compounds form part of the base of five-membered ring systems on which the rest of the research program will be built Several methyl-substituted derivatives were also studied. The results will be used to confirm the model for alkyl- substitution in the ring systems. Gas-phase spectra and fundamental- frequency assignments were completed for 2,3- and 2,5-dihydrofuran. Those compounds initiate wo… more
Date: March 1, 1993
Creator: Steele, W. V.; Chirico, R. D. & Klots, T. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Photomodulation spectroscopy of photocarrier dynamics, electronic defects and morphology of conducting polymers

Description: A variety of techniques were used: CW photomodulation, photomodulation in femtosecond and picosecond time ranges, CW resonant Raman scattering, transient photoinduced Raman scattering, electro-absorption, degenerate four-wave mixing, spin dependent photomodulation, and absorption detected magnetic resonance. The following conducting polymers were studied: polyacetylene, polythiophene, polydiacetylene 4-BCMU, polydiethynylsilanes, polysilane embedded in a-Si:H matrix, and fullerenes.
Date: January 1, 1993
Creator: Vardeny, Z. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

VHF EPR determination of the chemical forms of organic sulfur in coal. Final technical report, September 1, 1990--August 31, 1991

Description: This program addresses the need for innovative approaches to characterize the organic sulfur in Illinois Basin coals. We have developed a very high frequency electron paramagnetic resonance (EPR) spectrometer operating at the W-band of microwave frequencies (96 GHz). This instrument has shown unique sensitivity to heteroatoms in coal, and we believe the technique can be successfully applied for the non-destructive, direct determination of organic sulfur in coal. Preliminary data from Illinois c… more
Date: December 31, 1991
Creator: Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thermodynamic properties for polycyclic systems by non-calorimetric methods. Progress report, August 1, 1992--September 30, 1993

Description: A detailed vibrational spectroscopic study of furan, pyrrole, and thiophene has been completed. These compounds form part of the base of five-membered ring systems on which the rest of the research program will be built Several methyl-substituted derivatives were also studied. The results will be used to confirm the model for alkyl- substitution in the ring systems. Gas-phase spectra and fundamental- frequency assignments were completed for 2,3- and 2,5-dihydrofuran. Those compounds initiate wo… more
Date: March 1, 1993
Creator: Steele, W. V.; Chirico, R. D. & Klots, T. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemisorption and catalytic reactivity of cobalt and sulfur monolayers on ordered molybdenum surfaces

Description: Complex Co/Mo sulfide catalysts are modelled by the chemisorption of layers on Mo single crystal surfaces. Growth and structure of overlayers on flat, stepped and kinked surfaces were investigated. Growth of Co overlayers on clean and S covered Mo surfaces was studied using AES and CO chemisorption; results reveal that Co grows as a flat monolayer on clean Mo surfaces. Co multilayers then form 3-D islands. When Co is deposited on S covered surfaces, the S overlayer migrates to the top; this top… more
Date: March 1, 1992
Creator: Knight, C. C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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The mechanism of the oligomerization of thiophene-based para-quinodimethanes

Description: For the last decade, the Trahanovsky research group has focused on the study of various reactive molecules such as o-quinodimethanes (o-QDM`s) and p-quinodimethanes (p-QDM`s) derived from benzene, furan, and thiophene. These types of molecules are reactive and dimerize or polymerize at room temperature. One of the group`s interests is to understand the dimerization mechanism of these molecules. Paper 1 describes the preparation and dimerization product analyses of 2-ethylidene-5-methylene-2,5-d… more
Date: April 24, 1994
Creator: Wang, Yili
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Chemical dynamics in time and energy space

Description: The development of a versatile picosecond ultraviolet/vacuum ultraviolet temporal spectrometer and its potential use for measuring internal energy redistribution in isolated molecules are described in detail. A detailed description of the double-pass Nd:YAG amplifier and the dye amplifiers is given with the pulse energies achieved in the visible, ultraviolet, and vacuum ultraviolet. The amplified visible pulses are shown to be of sub-picosecond duration and near transform limited. The instrumen… more
Date: April 1, 1993
Creator: Myers, J. D.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

FEEDSTOCK-FLEXIBLE REFORMER SYSTEM (FFRS) FOR SOLID OXIDE FUEL CELL (SOFC)- QUALITY SYNGAS

Description: The U.S. Department of Energy National Energy Technology Laboratory funded this research collaboration effort between NextEnergy and the University of Michigan, who successfully designed, built, and tested a reformer system, which produced highquality syngas for use in SOFC and other applications, and a novel reactor system, which allowed for facile illumination of photocatalysts. Carbon and raw biomass gasification, sulfur tolerance of non-Platinum Group Metals (PGM) based (Ni/CeZrO2) reformin… more
Date: July 30, 2010
Creator: Jezierski, Kelly; Tadd, Andrew; Schwank, Johannes; Kibler, Roland; McLean, David; Samineni, Mahesh et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemisorption and catalytic reactivity of cobalt and sulfur monolayers on ordered molybdenum surfaces

Description: Complex Co/Mo sulfide catalysts are modelled by the chemisorption of layers on Mo single crystal surfaces. Growth and structure of overlayers on flat, stepped and kinked surfaces were investigated. Growth of Co overlayers on clean and S covered Mo surfaces was studied using AES and CO chemisorption; results reveal that Co grows as a flat monolayer on clean Mo surfaces. Co multilayers then form 3-D islands. When Co is deposited on S covered surfaces, the S overlayer migrates to the top; this top… more
Date: March 1, 1992
Creator: Knight, C. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Coal technology program quarterly progress report for the period ending December 31, 1975

Description: Installation of the bench-scale hydrocarbonization research system was completed and initial pressurization was followed by heat up, leak checking, and testing of instrumentation. Shakedown runs were completed using 5 and 20 lb of pulverized coal as feed and pyrolyzing the coal at approx. 1050/sup 0/F under 5 atm of nitrogen pressure. Some excellent results have been obtained in the additive agglomeration studies using liquid additives designed for the petroleum industry. Characterization studi… more
Date: March 1, 1976
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of fundamental catalytic properties of MoS2/WS2 nanotubes and nanoclusters for desulfurization catalysis - a surface temperature study

Description: The prior project consisted of two main project lines. First, characterization of novel nanomaterials for hydrodesulfurization (HDS) applications. Second, studying more traditional model systems for HDS such as vapor-deposited silica-supported Mo and MoSx clusters. In the first subproject, we studied WS2 and MoS2 fullerene-like nanoparticles as well as WS2 nanotubes. Thiophene (C4H4S) was used as the probe molecule. Interestingly, metallic and sulfur-like adsorption sites could be identified on… more
Date: July 5, 2012
Creator: Burghaus, U.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Transition metal activation and functionalization of carbon-hydrogen bonds. Progress report, December 1, 1989--November 30, 1992

Description: We are investigating the fundamental thermodynamic and kinetic factors that influence carbon-hydrogen bond activation at homogeneous transition metal centers and the conversion of hydrocarbons into functionalized products of potential use to the chemical industry. Advances have been made in both understanding the interactions of hydrocarbons with metals and in the functionalization of hydrocarbons. We have found that RhCl(PR{sub 3}){sub 2}(CNR) complexes can catalyze the insertion of isonitrile… more
Date: June 1, 1992
Creator: Jones, W. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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