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in subjects: "Zirconium Compounds 400201* -- Chemical & Physicochemical Properties"  
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Theoretical aspects of solid state reactions in a mixed particulate ensemble and kinetics of lead zirconate formation

Description: A theoretical analysis was carried out to estimate the quasi-steady-state external mass transport by lattice, surface and gaseous diffusion in terms of the stereologically measurable microstructural parameters of a mixed powder compact. It was shown that the gaseous transport can be described by a single dimensionless quantity termed sublimation transport modulus. Using these equations, the relative importance of the alternate external transport modes can be evaluated. Experimental work determi… more
Date: September 1, 1979
Creator: Chandratreya, S.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Synthesis and characterization of some binary and ternary zirconium iodides

Description: Studies of binary ZrI/sub 4/-Zr and ternary CsI-Zr-ZrI/sub 4/ systems have produced several new compounds. The new binary compounds include two polymorphs of ZrI/sub 2/ (..cap alpha.. and ..beta..) as well as a phase described earlier as ZrI/sub 1/ /sub 8/. ..cap alpha..-ZrI/sub 2/ forms as black lath-like crystals by vapor phase transport reactions between Zr and ZrI/sub 4/ from 700 to 825/sup 0/C. Its structure is monoclinic space group P2/sub 1//m with a = 6.821(2), b = 3.741(1), c = 14.937(… more
Date: October 1, 1981
Creator: Guthrie, D. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Support effects studied on model supported catalysts

Description: Composition and structure of oxide support materials can change the catalytic behavior of metal and oxide catalysts. Model catalysts are being studied in which the active phase is deposited on flat oxide substrates, with emphasis on metals catalysis for automotive emissions control and acidity in supported oxides. Research is reported in the following areas: particle-size effects, support effects on ZnO and zirconia, support effects on ceria, supported oxides, and low energy ion scattering (no … more
Date: February 1, 1993
Creator: Gorte, R.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low severity upgrading of F-T waxes with solid superacids

Description: To avoid methane production in F-T synthesis on Fe catalysts, efforts are being made on conversion of synthesis gas to high molecular weight hydrocarbons, such as waxes. Strong acidity of sulfated zirconium oxides, ZrO[sub 2]/SO[sub 4], is being used to pretreat long-chain paraffins with carbon numbers greater than n-C[sub 32]. Progress during this period is reported on reactivity of Pt/ZrO[sub 2]/SO[sub 4] for hydrocracking n-C[sub 32] and on effects of hydride donor solvent on hydrocracking o… more
Date: January 1, 1992
Creator: Tierney, J.W. & Wender, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High temperature thermodynamics and vaporization of the zirconium--niobium--oxygen system

Description: The vaporization behavior of the Zr--Nb--O system was studied by means of successive vaporization, Knudsen effusion-target collection experiments, and mass spectrometric analysis of the vapors effusing from a Knudsen crucible. The successive vaporization experiments were performed on two ternary samples in open crucibles. X-ray powder diffraction patterns of the residues and x-ray fluorescence analysis of the condensates and residues indicated the preferential vaporization of niobium-containing… more
Date: May 18, 1978
Creator: Rinehart, G.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low severity upgrading of F-T waxes with solid superacids

Description: In the past year, we synthesized a Pt/ZrO[sub 2]/SO[sub 4] catalyst which exhibits high conversions and selectivity for desirable products from long-chain paraffins, such as n-hexadecane, n-dotriacontane(n-C[sub 32]) and a SASOL wax(C[sub 58]-C[sub 64]). The catalyst preparation procedure has been carefully worked out and is reproducible. Isomerization and hydrocracking activities of long-chain paraffins and selectivities to various products were examined under mild conditions: 443 K and 2.5 MP… more
Date: January 1, 1992
Creator: Tierney, J.W. & Wender, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent electroanalytical studies in molten fluorides. [LiF--BeF/sub 2/--ThF/sub 4/ (ZrF/sub 4/)]

Description: This paper summarizes the voltametric and chronopotentiometric studies of Bi, Fe, Te, oxide and U(IV)/U(III) ratio determinations in molten LiF--BeF/sub 2/--ThF/sub 4/ (72-16-12 mole percent) and LiF--BeF/sub 2/--ZrF/sub 4/ (65.6-29.4-5.0 mole percent). 54 references, 11 figures. (DLC)
Date: January 1, 1976
Creator: Manning, D. L. & Mamantov, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of a catalyst for conversion of syngas-derived materials to isobutylene

Description: The CO conversion and isobutylene yield for Runs 11 to 20 (except run 12) at the conditions of 450[degree]C, 1,200 psig, and 1,920 gas hourly space velocity (GHSV), Is given in Table 2. These conditions generally provide the maximum CO conversion for each run. Runs 5 to 10 is also provided in Table 2 for a comparison. The description of the catalysts also given in Table 2 includes the composition, method of preparation, and calcination temperature for each catalyst tested. Data for Runs 12 and … more
Date: April 3, 1992
Creator: Gajda, G.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Synthesis and structural characterization of some compounds involving metal-metal bonding of tellurium, bismuth, and zirconium. [Complex with hexaoxadiazabicyclohexacosane potassium]

Description: Salts of the tritelluride(2-) and tetrabismuthide(2-) ions with the complex cation (4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo(8.8.8)hexacosane potassium) (abbreviated crypt K/sup +/) were synthesized and their structures determined. The dark red (crypt K/sup +/)/sub 2/ Te/sub 3//sup 2 -/.en was produced by oxidation of K/sub 2/Te with an excess of tellurium and the very dark green (crypt K/sup +/)/sub 2/Bi/sub 4//sup 2 -/ was produced by the reaction of either K/sub 3/Bi, K/sub 3/Bi/sub 2/, K/s… more
Date: August 1, 1978
Creator: Cisar, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Synthesis and chemistry of cationic d sup 0 metal alkyl complexes

Description: The objective of this project is to develop new types of electrophilic metal alkyl complexes for catalytic C-H activation and olefin polymerization chemistry, and associated fundamental mechanistic studies. We have focused our efforts on four classes of early metal alkyl complexes: (1) cationic group 4 Cp{sub 2}M(R){sup +} complexes (1) which are active species in Cp{sub 2}MX{sub 2}-based Ziegler-Natta olefin polymerization catalyst systems and which catalyze productive C-H activation reactions… more
Date: January 1, 1991
Creator: Jordan, R. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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