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Nuclear Synthesis of Element 43 (Tc)#x

Description: The following report on the nuclear synthesis of technetium is based on work performed under contract No. W-7405-eng-26 for the Atomic Energy Project at Oak Ridge National Laboratory.
Date: June 14, 1948
Creator: Motta, E. E. & Boyd, G. E.
Partner: UNT Libraries Government Documents Department

Facile, scalable synthesis of edge-halogenated graphene nanoplatelets as efficient metal-free eletrocatalysts for oxygen reduction reaction

Description: Article on facile, scalable synthesis of edge-halogenated graphene nanoplatelets as efficient metal-free electrocatalysts for oxygen reduction reaction.
Date: February 1, 2013
Creator: Jeon, In-Yup; Choi, Hyun-Jung; Choi, Min; Seo, Jeong-Min; Jung, Sun-Min; Kim, Min-Jung et al.
Partner: UNT College of Engineering

Long-Term Testing of Rhodium-Based Catalysts for Mixed Alcohol Synthesis – 2013 Progress Report

Description: The U.S. Department of Energy’s Pacific Northwest National Laboratory has been conducting research since 2005 to develop a catalyst for the conversion of synthesis gas (carbon monoxide and hydrogen) into mixed alcohols for use in liquid transportation fuels. Initially, research involved screening possible catalysts based on a review of the literature, because at that time, there were no commercial catalysts available. The screening effort resulted in a decision to focus on catalysts containing rhodium and manganese. Subsequent research identified iridium as a key promoter for this catalyst system. Since then, research has continued to improve rhodium/manganese/iridium-based catalysts, optimizing the relative and total concentrations of the three metals, examining baseline catalysts on alternative supports, and examining effects of additional promoters. Testing was continued in FY 2013 to evaluate the performance and long-term stability of the best catalysts tested to date. Three tests were conducted. A long-term test of over 2300 hr duration at a single set of operating conditions was conducted with the best carbon-supported catalyst. A second test of about 650 hr duration at a single set of operating conditions was performed for comparison using the same catalyst formulation on an alternative carbon support. A third test of about 680 hr duration at a single set of operating conditions was performed using the best silica-supported catalyst tested to date.
Date: September 23, 2013
Creator: Gerber, Mark A.; Gray, Michel J. & Thompson, Becky L.
Partner: UNT Libraries Government Documents Department

Synthetic Approaches to (smif)₂Ti (smif=1,3-di-(2-pyridyl)-2-azaallyl) Reveal Redox Non-Innocence and C-C Bond-Formation

Description: Article discussing synthetic approaches to (smif)₂Ti(smif=1,3-di-(2-pyridyl)-2-azallyl) revealing redox non-innocence and C-C bond-formation.
Date: July 25, 2012
Creator: Frazier, Brenda A.; Wolczanski, Peter T.; Keresztes, Ivan; DeBeer, Serena 1973-; Lobkovsky, Emil B.; Pierpont, Aaron W. et al.
Partner: UNT College of Arts and Sciences

Physical Chemistry of the Fischer-Tropsch Synthesis

Description: From Summary: "This paper summarizes the results of physicochemical studies of the Fischer-Tropsch synthesis (the catalytic hydrogenation of carbon monoxide) undertaken by the Federal Bureau of Mines as part of its program on improving processes for producing liquid fuels from coal."
Date: 1959
Creator: Anderson, R. B.; Shultz, J. F.; Hofer, L. J. E. & Storch, H. H.
Partner: UNT Libraries Government Documents Department

Kinetics of the Fischer-Tropsch Synthesis on Iron Catalysts

Description: From Introduction: "The first of this Bulletin describes rate studies on iron catalysts and the second part the influence of catalyst geometry on rate. The appendix describes special experiments at higher pressure than those usually employed in the synthesis on iron catalysts."
Date: unknown
Creator: Anderson, R. B.; Karn, F. S. & Shultz, J. F.
Partner: UNT Libraries Government Documents Department

Synthesis of Selected 2-imidazolines

Description: Since Djerassi and Scholz found that 2-(aryloxy-methyl)imidazolines and their hydrochloride salts exhibit vasoconstrictive properties, the 1,2-(I) 1,3-(II) and 1,4-bis-(2-imidazolinylmethoxy) benzene (III) analogs (Fig. 1, p.2) were chosen for synthesis in order to test them for their effective vasoconstrictive characteristics and for whatever other physiological properties they might exhibit.
Date: June 1966
Creator: Maurer, Larry Eugene
Partner: UNT Libraries

A Possible New Volatile Compound of Uranium

Description: A report discussing a possible new volatile compound of uranium, its probable properties, and attempts to synthesize it. Though the possible new compound was not successfully synthesized, the author provides suggestions for future work.
Date: July 1943
Creator: Lander, John Joseph
Partner: UNT Libraries Government Documents Department

Simplification of Methods for PET Radiopharmaceutical Syntheses

Description: In an attempt to develop simplified methods for radiochemical synthesis of radiopharmaceuticals useful in Positron Emission Tomography (PET), current commercially available automated synthesis apparati were evaluated for use with solid phase synthesis, thin-film techniques, microwave-accelerated chemistry, and click chemistry approaches. Using combinations of these techniques, it was shown that these automated synthesis systems can be simply and effectively used to support the synthesis of a wide variety of carbon-11 and fluorine-18 labeled compounds, representing all of the major types of compounds synthesized and using all of the common radiochemical precursors available. These techniques are available for use to deliver clinically useful amounts of PET radiopharmaceuticals with chemical and radiochemical purities and high specific activities, suitable for human administration.
Date: December 27, 2011
Creator: Kilbourn, Michael, R.
Partner: UNT Libraries Government Documents Department

Low-Temperature Synthesis Routes to Intermetallic Superconductors

Description: Over the past few years, our group has gained expertise at developing low-temperature solution-based synthetic pathways to complex nanoscale solids, with particular emphasis on nanocrystalline intermetallic compounds. Our synthetic capabilities are providing tools to reproducibly generate intermetallic nanostructures with simultaneous control over crystal structure, composition, and morphology. This DOE-funded project aims to expand these capabilities to intermetallic superconductors. This could represent an important addition to the tools that are available for the synthesis and processing of intermetallic superconductors, which traditionally utilize high-temperature, high-pressure, thin film, or gas-phase vacuum deposition methods. Our current knowledge of intermetallic superconductors suggests that significant enhancements could result from the inherent benefits of low-temperature solution synthesis, e.g. metastable phase formation, control over nanoscale morphology to facilitate size-dependent property studies, robust and inexpensive processability, low-temperature annealing and consolidation, and impurity incorporation (for doping, stoichiometry control, flux pinning, and improving the critical fields). Our focus is on understanding the superconducting properties as a function of synthetic route, crystal structure, crystallite size, and morphology, and developing the synthetic tools necessary to accomplish this. This research program can currently be divided into two classes of superconducting materials: intermetallics (transition metal/post transition metal) and metal carbides/borides. Both involve the development and exploitation of low-temperature synthesis routes followed by detailed characterization of structures and properties, with the goal of understanding how the synthetic pathways influence key superconducting properties of selected target materials. Because of the low-temperature methods used to synthesize them and the nanocrystalline morphologies of many of the products, the superconductors and their nanocrystalline precursors are potentially amenable to inexpensive and large-scale solution-based processing into wires, coatings, films, and templated or patterned structures with nanoscale and microscale features. Also, because of the new synthetic variables that play a key role in the low-temperature formation of intermetallics, the possibility exists to discover ...
Date: January 8, 2008
Creator: Schaak, Raymond E.
Partner: UNT Libraries Government Documents Department

Studies of the membrane and DNA gyrase inhibiting antibiotics on pigment synthesis in Corynebacterium poinsettiae

Description: The purpose of this study was (1) to determine whether a correlation exists among the protein profiles, extracted from cell membranes of mutants belonging to five pigment cluster groups, (2) to locate the protein moiety and cartenoprotein complex in the membranes of wild type and colorless mutant (designated W-19) of C. poinsettae and to show whether there are any structural differences between cell membranes of the wild type and a colorless mutant, (3) to determine the effect of six antibiotics on cartenoid gene expression.
Date: August 1988
Creator: Tabarya, Daniel
Partner: UNT Libraries

Synthesis of aziridine analogues of pyrethroids

Description: Rules which correlate structure and insecticidal activity of pyrethroids have evolved over the last thirty years from the results obtained in the testing of various synthetic pyrethroids. The major portion of these rules have dealt either with the development of new alcohol moieties or variations in the unsaturated side chain of the cyclopropane ring. There has been very little work done concerning modifications of the cyclopropane ring. This study was initiated to discover the affect of substituting an aziridin ring for the cyclopropane ring found in pyrethroids.
Date: May 1981
Creator: Sheppard, Rex Gerald
Partner: UNT Libraries