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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

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

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

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

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

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

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

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

Photoelectric Emission Measurements for CVD Grown Polycrystalline Diamond Films

Description: We examined CVD grown polycrystalline diamond films having different methane concentrations to detect defects and study the possible correlation between the methane concentration used during the growth process and the defect density. SEM and Raman results show that the amorphous and sp2 carbon content of the films increases with methane concentration. Furthermore, photoelectric emission from diamond is confirmed to be a two-photon process, hence the electrons are emitted from normally unoccupied states. We found that the photoelectric yield, for our samples, decreases with the increase in methane concentration. This trend can be accounted for in two different ways: either the types of defects observed in this experiment decrease in density as the methane concentration increases; or, the defect density stays the same or increases, but the increase in methane concentration leads to an increase in the electron affinity, which reduces the overall photoelectric yield.
Date: August 1999
Creator: Hassan, Tarek
Partner: UNT Libraries

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 Ether-free Organomagnesium Compounds

Description: At the time this work was begun, there was some confusion about the technique necessary for the successful synthesis of organomagnesium compounds in hydrocarbon solvents and without solvents. It was decided to repeat the work of Bryce-Smith and Zakharkin. Thus began the study of the synthesis of organomagnesium compounds without solvents; the study of the reaction products of these organomagnesium compounds in hydrocarbons plus 2-butanone compared to the reaction products of the corresponding etheral Grignard reagent plus 2-butanone; and a preliminary study of the nature of these organomagnesium compounds in hydrocarbon solvents.
Date: August 1967
Creator: Hanicak, John E.
Partner: UNT Libraries