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Deploymerization of coal by direct solvent attack. Semi-annual report, April 1, 1983-August 31, 1983

Description: The depolymerization of Illinois No. 6 coal by a series of solvents having different basecities (pK/sub a/) and nucleophilicities (Swain-Scott nu values) showed no dependence on either the basicity of nucleophilicity of the solvents. As expected, the conversion decreases as the temperature of the reaction is reduced, but the lower the reaction temperature, the higher the percentage of amine incorporation becomes in the products. 5 tables.
Date: September 15, 1983
Creator: Larsen, J. W. & Mohammadi, 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

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 the 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 experi… more
Date: September 1, 1991
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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An NMR (nuclear magnetic resonance) investigation of the chemical association and molecular dynamics in asphalt ridge tar sand ore and bitumen

Description: Preliminary studies on tar sand bitumen given in this report have shown that the reassociation of tar sand bitumen to its original molecular configuration after thermal stressing is a first-order process requiring nearly a week to establish equilibrium. Studies were also conducted on the dissolution of tar sand bitumen in solvents of varying polarity. At a high-weight fraction of solute to solvent the apparent molecular weight of the bitumen molecules was greater than that of the original bitum… more
Date: September 1, 1987
Creator: Netzel, D. A. & Coover, P. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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THE PHOTOCHEMISTRY OF PYRIDINE N-OXIDE

Description: The authors wish to report their results on the photolysis of pyridine N-oxide in alcoholic solution. Both methanol and ethanol solutions of pyridine N-oxide were irradiated. The reaction mixture was analyzed by gas-liquid chromatography (GLC) using a 2.5% FFAP on Chrom G column and a Porapak Q column. In order to collect the products, the volume of the photolysis solution was reduced in vacuo and the resulting mixture was separated by preparative GLC.
Date: September 14, 1967
Creator: Alkaitis, Algis & Calvin, Melvin.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dissolving coal at moderate temperatures and pressures. Final report, August 20, 1982-September 30, 1984. [Benzylamine]

Description: The main objectives of this research were to make Illinois No. 6 coal liquid or soluble with inexpensive reagents (e.g., solvolysis with methanol and acids), without high pressure equipment, and to see if our soluble products would be more reactive than whole coal in liquefaction processes. These efforts are unpromising. However, efforts to make coal soluble by oxidation with nitric acid gave encouraging results. When Illinois No. 6 and Wyodak coals were allowed to stand in sunlight for 282 day… more
Date: September 21, 1984
Creator: Mayo, F. R.; Hirschon, A. S. & Sundback, K. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A molecular surface science study of the structure of adsorbates on surfaces: Importance to lubrication

Description: The interaction and bonding of atoms and molecules on metal surfaces is explored under ultra-high vacuum conditions using a variety of surface science techniques: high resolution electron energy loss spectroscopy (HREELS), low energy electron diffraction (LEED), thermal desorption spectroscopy (TDS), Auger electron spectroscopy (AES), work function measurements, and second harmonic generation (SHG). 164 refs., 51 figs., 3 tabs.
Date: September 1, 1986
Creator: Mate, C. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear magnetic relaxation studies of semiconductor nanocrystals and solids

Description: Semiconductor nanocrystals, small biomolecules, and {sup 13}C enriched solids were studied through the relaxation in NMR spectra. Surface structure of semiconductor nanocrystals (CdS) was deduced from high resolution {sup 1}H and {sup 13}C liquid state spectra of thiophenol ligands on the nanocrystal surfaces. The surface coverage by thiophenol was found to be low, being 5.6 and 26% for nanocrystal radii of 11.8 and 19.2 {angstrom}. Internal motion is estimated to be slow with a correlation tim… more
Date: September 1, 1993
Creator: Sachleben, J. R.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Use of solid waste for chemical stabilization: Adsorption isotherms and {sup 13}C solid-state NMR study of hazardous organic compounds sorbed on coal fly ash

Description: Adsorption of hazardous organic compounds on the Dave Johnston plant fly ash is described. Fly ash from Dave Johnston and Laramie River power plants were characterized using elemental, x-ray, and {sup 29}Si NMR; the Dave Johnston (DJ) fly ash had higher quartz contents, while the Laramie River fly ash had more monomeric silicate anions. Adsorption data for hydroaromatics and chlorobenzenes indicate that the adsorption capacity of DJ coal fly ash is much less than that of activated carbon by a f… more
Date: September 1, 1993
Creator: Netzel, D. A.; Lane, D. C.; Rovani, J. F.; Cox, J. D.; Clark, J. A. & Miknis, F. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of the deswelling characteristics of Illinois No. 6 coal by nuclear magnetic resonance imaging (NMRI) and NMR techniques

Description: NMRI can observe the internal and external physical structural changes of a sample as well as the solvent penetration process without physical handing. Although the spatial resolution achievable in NMRI of coal samples is only 20--40 {mu}m swelling of coal can be measured because a polar solvent expands the coal to almost twice its original volume. NMR can also monitor the change of solvent concentration m a swollen coal (by integrating the peak areas of the NMR spectra), and can also examine s… more
Date: September 1, 1993
Creator: Hou, L.; Hatcher, P. G.; French, D. C. & Botto, R. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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I. Niobium(IV) Bromide and Pyridine Adducts of the Niobium(IV) Halides

Description: Technical report. From Abstract : "Reaction of NbBr5 and niobium metal in a sealed tube under a temperature gradient from 410° to 350° gave NbBr4 in good yields. However, an increase in the higher temperature from 410° to 450° was sufficient to eliminate NbBr4 as a product and cause deposition of a lower bromide."
Date: September 5, 1962
Creator: McCarley, Robert E. & Torp, Bruce A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Preparation of TaBr4, TaI4 and Pyridine Adducts of the Tantalum(IV) Halides

Description: Technical report. From Abstract : "The necessary conditions for preparation of TaBr4 and TaI4 by reduction of the pentahalides with tantalum or aluminum metal in a sealed tube under a controlled temperature gradient have been demonstrated."
Date: September 5, 1962
Creator: McCarley, R. E. & Boatman, J. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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