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in subjects: "Arsenic Oxides"  
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A{sub 2}Zn{sub 3}As{sub 2}O{sub 2}(A = Ba, Sr): a rare example of square planar zinc

Description: Purpose of this study was to explore synthesis of novel solid-state compounds that could potentially exhibit interesting or useful physical properties. Goal was to extend the classes of compounds A{sub 2}Mn{sub 3}Pn{sub 2}O{sub 2} (A=Sr,Ba; Pn=P,As,Sb,Bi) to include a transition metal other than Mn. High-temperature fluxes were used to produce these new compounds.
Date: June 1994
Creator: Keane, P. M. & Burdett, J. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Origin of the Time-Dependence of Wet Oxidation of AlGaAs

Description: The time-dependence of the wet oxidation of high-Al-content AlGaAs can be either linear, indicating reaction-rate limitation, or parabolic, indicating diffusion-limited rates. The transition from linear to parabolic time dependence can be explained by the increased rate of the formation of intermediate As{sub 2}O{sub 3} vs. its reduction to elemental As. A steadily increasing thickness of the As{sub 2}O{sub 3}-containing region at the oxidation front will shift the process from the linear to th… more
Date: February 15, 1999
Creator: Allerman, A. A.; Ashby, C. I. H.; Bridges, M. M.; Hammons, B. E. & Hou, H. Q.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Coordination and valence of europium in [Eu({alpha}-2-As{sub 2}W{sub 17}O{sub 61}){sub 2}]{sup 17{minus}} and [Eu(W{sub 5}O{sub 18}){sub 2}]{sup 9{minus}}

Description: Europium L{sub 3}-edge X-ray absorption fine structure (XAFS) spectroelectrochemistry was used to determine the valence of europium in [Eu({alpha}-2-As{sub 2}W{sub 17}O{sub 61}){sub 2}]{sup 17{minus}} and [Eu(w{sub 5}O{sub 18}){sub 2}]{sup 9{minus}}. Dilute solutions of these anions in aqueous supporting electrolytes were examined at ambient temperature and at extreme potentials. In situ XANES (X-ray absorption near edge structure) data revealed that Eu is trivalent in both [Eu({alpha}-2-As{sub… more
Date: September 1, 1997
Creator: Antonio, M.R.; Soderholm, L.; Jennings, G.; Francesconi, L.C.; Dankova, M. & Bartis, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Refractive Index and Hygroscopic Stability of Al(x)Ga(1-x)As Native Oxides

Description: The authors present prism coupling measurements on Al{sub x}Ga{sub 1{minus}x}As native oxides showing the dependence of refractive index on composition (0.3 {le} x {le} 0.97), oxidation temperature (400 {le} T {le} 500), and carrier gas purity. Index values range from n = 1.490 (x = 0.9, 400) to 1.707 (x = 0.3, 500 C). The oxides are shown to adsorb moisture, increasing their index by up to 0.10 (7%). Native oxides of Al{sub x}Ga{sub 1{minus}x}As (x {le} 0.5) have index values up to 0.27 higher… more
Date: July 8, 1999
Creator: Blum, O.; Epstein, R. J.; Hou, H.; Hall, D. C.; Kou, L.; Luo, Y. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF A GEOCHEMICAL MODEL FOR URANIUM TRANSPORT IN THE UNSATURATED AND SATURATED SEDIMENTS AT THE 200 WEST AREA OF THE US DEPARTMENT OF ENERGY HANFORD SITE WASHINGTON (SEPTEMBER 2004)

Description: Final Deliverable under GWP-HQ-LMT-02 contract for Hanford Sci. & Tech. Gp. to BHI. The scope of work covered laboratory analyses and gephysical logging for 299-W19-43 near the 200 West U Plant. Other isotopic analyses were conducted for holes around 216-U-1&2, including U-236.
Date: March 24, 2010
Creator: SC, ADAMS & SW, PETERSEN
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Scanning SQUID microscopy on polycrystalline SmFeAsO_{0.85} and NdFeAsO_{0.94}F_{0.06}

Description: The order parameter of the recently-discovered ferric arsenide family of superconductors remains uncertain. Some early experiments on polycrystalline samples suggested line nodes in the order parameter, however later experiments on single crystals have strongly supported fully-gapped superconductivity. An absence of nodes does not rule out unconventional order: {pi} phase shifts between the separate Fermi sheets and time-reversal symmetry-breaking components in the order parameter remain possib… more
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Moler, Kathryn A.; Huber, Martin E.; Ren, Zhi-An & Zhao, Zhong-Xian
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Limits on the Superconducting Order Parameter in NdFeAsO_{1-x}F_y from Scanning SQUID Microscopy

Description: Identifying the symmetry of the superconducting order parameter in the recently-discovered ferrooxypnictide family of superconductors, RFeAsO{sub 1-x}F{sub y}, where R is a rare earth, is a high priority. Many of the proposed order parameters have internal {pi} phase shifts, like the d-wave order found in the cuprates, which would result in direction-dependent phase shifts in tunneling. In dense polycrystalline samples, these phase shifts in turn would result in spontaneous orbital currents and… more
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Huber, Martin E.; Ren, Zhi-An; Yang, Jie; Zhao, Zhong-Xian et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Suppression of fine ash formation in pulverized coal flames. Quarterly technical progress report No. 3, April 1, 1993--June 30, 1993

Description: One of the major obstacles to the economical use of coal is managing the behavior of its mineral matter. Ash size and composition are of critical importance for a variety of reasons. Fly ash size and emissivity affect radiant furnace heat transfer. Heat transfer is also affected by the tendency of ash to adhere to heat transfer surfaces, and the properties of these deposits. Removal of ash from flue gas by electrostatic precipitators is influenced by both particle size and particle resistivity.… more
Date: July 23, 1993
Creator: Kramlich, J. C.; Hoffman, D. A. & Butcher, E. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sulfur polymer cement encapsulation of RCRA toxic metals and metal oxides

Description: A study was conducted to determine the suitability of Sulfur Polymer Cement (SPC) encapsulation technology for the stabilization of RCRA toxic metal and metal oxide wastes. In a series of bench-scale experiments, the effects of sodium sulfide additions to the waste mixture, residence time, and temperature profile were evaluated. In addition, an effort was made to ascertain the degree to which SPC affords chemical stabilization as opposed to physical encapsulation. Experimental results have demo… more
Date: June 1, 1995
Creator: Calhoun, C.L. Jr.; Nulf, L.E. & Gorin, A.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Trace Metal Speciation in Saline Waters Affected by Geothermal Brines. [GEOCHEM]

Description: A description is given of the chemical equilibrium computer program GEOCHEM, which has been developed to calculate trace element speciation in soil, irrigation, drainage, or Salton Sea waters affected by geothermal brine. GEOCHEM is applied to irrigation water-brine mixtures and to Salton Sea water-brine mixtures in order to compute the chemical speciation of the elements Cd, Cu, Hg, Ni, Pb, and Zn, along with the oxyanions of As and B. The results suggest that the computer simulation can have … more
Date: November 1, 1977
Creator: Sposito, G. & Page, A. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical Engineering Division physical inorganic chemistry. Annual report, July 1975--June 1976

Description: The thermal conductivity of acetonitrile vapor has been measured at temperatures between 338 and 387/sup 0/K and pressures between 100 and 1050 torr. The pressure dependence of the thermal conductivities indicates the presence of dimeric vapor species with an association constant given by RT ln K/sub 2/ (atm/sup -1/) = 5002 - 21.15 T. Molecular orbital studies of hydrogen-bonded methyl alcohol vapor complexes indicate that, the cyclic tetramer is especially stable. Preliminary calculations on t… more
Date: January 1, 1976
Creator: Blander, M.; Curtiss, L. A.; Hsu, C. C.; Kucera, G. H.; Marr, J. J.; Papatheodorou, G. N. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear medicine technology. Progress report for quarter ending September 30, 1979

Description: Adrenal uptake in rats of /sup 117m/Sn-labeled 23-(trimethyl stanna)-24-nor-5..cap alpha..-cholan-3..beta..-o1 is demonstrated. The adrenal:blood and adrenal:liver ratios were 33:1 and 9:1, only one day after intravenous administration. A variety of /sup 117m/Sn-labeled steroids with structural modifications were also prepared to determine their effects on the adrenal uptake of these unusual steroids. Structural features required for significant adrenal uptake were determined. The diffusion cha… more
Date: January 1, 1979
Creator: Knapp, F. F. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear Medicine Technology Progress Report for Quarter Ending June 30, 1980

Description: Results of experiments demonstrated that the alkyl portion of 9-telluraheptadecanoic acid (9-THDA) is retained in the myocardial tissue of rats to the same extent as radioactivity from /sup 123m/Te-9-THDA. Tissue distribution experiments in rats one hr after injection of 10-(/sup 14/C)-9-telluraheptadecanoic acid were compared with the results of a parallel study using /sup 123m/Te-9-THDA. The results indicate that the alkyl region of 9-THDA is retained in the myocardium and that labeling of th… more
Date: January 1, 1981
Creator: Knapp, Furn F., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear medicine technology. Progress report, quarter ending March 31, 1980

Description: The successful detection of experimentally produced myocardial infarctions in rats and dogs using /sup 123m/Te-9-telluraheptadecanoic acid (9-(/sup 123m/Te)-THDA) is described. Preferential localization of radioactivity in normal myocardial tissue of rats that had experimentally produced infarctions was also demonstrated by tissue distribution studies following injection of 9-(/sup 123m/Te)-THDA. The effects of chain length on the myocardial uptake of /sup 75/Se-labeled long-chain fatty acids w… more
Date: October 1, 1980
Creator: Knapp, F. F. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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