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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Search for unconventional superconductivity in transition metal compounds

Ko, Yuen Ting January 2010 (has links)
No description available.
32

Some organotransition metal chemistry of the carbon-carbon triple bond / by George Anthony Koutsantonis

Koutsantonis, George Anthony January 1989 (has links)
Includes bibliographical references / 332, [6] leaves ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1990
33

Technetium(V), Rhenium(V), and Technetium(III) complexes /

Parsons, Teresa L., January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 147-169). Also available on the Internet.
34

Technetium(V), Rhenium(V), and Technetium(III) complexes

Parsons, Teresa L., January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 147-169). Also available on the Internet.
35

Studies on the structures and properties of bimetallic uranium transition metal and hybrid organic-inorganic compounds

Yu, Yaqin. Albrecht-Schmitt, Thomas E., January 2009 (has links)
Thesis (Ph. D.)--Auburn University, 2009. / Abstract. Includes bibliographical references.
36

Chemistry of transition metal carbonyls and their derivatives

Douglas, Walter Mark, January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
37

Structural properties of pyrazolyl-bridged diiridium complexes

Brost, Ron D. 26 June 2018 (has links)
The x-ray structures of several alkyl halide, alkyl dihalide, and hydrogen adducts to pyrazolyl-bridged diiridium complexes [special characters omitted] are determined. The diiridium (bis-pyrazolyl) core of these complexes enables contact between the two centers so that metal-metal bond formation may occur, exemplified by a short iridium-iridium distance of 2.78(I) A in the diiridium(II) complex [special characters omitted]. Oxidation mechanisms are postulated based on reaction kinetics. The oxidative addition of methyl iodide to [special characters omitted] is observed to occur by a two-step mechanism, where a high positive ΔS‡ term may be due to a highly ordered intermediate. This is proposed as evidence for an [special characters omitted] addition, where coordination of the alkyl halide is followed by halide dissociation and migration to a trans diaxial coordination site. Different kinetics of the reaction are observed in THF and benzene, which is also attributed to a polar [special characters omitted] intermediate. Occupation of the 3,3’ and 5,5’ positions of the pyrazolyl ligand decreases the reaction rate by an order of magnitude or greater, which indicates steric inhibition of the reaction by the bridging ligands. Experimental evidence for a competing light-induced reaction that corresponds to a radical-chain mechanism rather than the dark [special characters omitted] reaction is also presented. Oxidative isomerization of an iodo (iodomethylene) complex to the methylene-bridged isomer is determined to be an intramolecular process based on isotope labelling experiments and kinetics. Negligible isomerization to the bridging methylene complex under ambient conditions is attributed to coordinative saturation; the stability of [special characters omitted] is likewise due to coordinative saturation of the metal centers. The addition of hydrogen or hydride to [special characters omitted] is possible through a number of synthetic routes, but the stereochemistry of the iridium(II) hydrido complexes is such that the metal-hydride and iridium-iridium bonds do not occupy coordination sites trans to each other: it is proposed that the strong σ-trans effect of the hydride induces structural rearrangements in substitution reactions so that stereochemistry of parent complexes is not conserved. This is demonstrated by the x-ray structures of [special characters omitted]. The hydride ligand promotes nucleophilic attack on an electron-rich iridium center; thus water and other Lewis bases are found to react with the cationic diiridium hydride complex [special characters omitted]. / Graduate
38

Responsive luminescence toolbox for biological applications

Li, Hongguang 15 February 2016 (has links)
In chapter one, literature review have been down about the photophysical properties of lanthanide complexes and their applications. In chapter 2, the design and synthesis of water soluble cyclen based europium complexes with cyclin A specific peptides were described. Linear and two-photon induced hypersensitive europium emission gave the real time signalling and also enhanced the two-photon induced emission from 12GM to 68GM after Cyclin A binding. In chapter 3, the design of water soluble multi-modal porphyrin based compounds for key cell cycle regulator- Plk 1 imaging and cancer cells inhibition were described. Two water soluble porphyrin compounds have been synthesized and shown the specific photodynamic therapy treatment in the cancer cells via the selectively binding with Polo-like kinase 1 (Plk1). Plk1 is responsible for cell cycle regulation. Commercial or known Plk1 inhibitor/bioprobes are always poor cell internalization and easily to be damaged by enzymatic degradation. In addition, these markers are not available to image and inhibit the Plk1 as dual function probe. We introduced a new approach amphiphilic porphyrin with Plk1 specific peptide. Our compounds shown responsive emission enhancement upon binding with Plk1 in aqueous medium. In vitro, it can triggered G2-M phase arrest and inhibited the cancer cells specific as Plk1 is overexpressed in cancer cell. In chapter 4, we designed and synthesized a platinumeuropium complex (PtEuL401) as a controlled delivery vehicle of cisplatin. PtEuL401 shown responsive emission with the appropriate light excitation in aqueous and in vivo during the drug delivery process. Compared with the existing prodrugs, we offer real-time monitoring of the therapy process. Also, the long emission lifetimes of lanthanides creates room for further development in time-resolved imaging protocols which eliminates the problem of autofluorescence.
39

Nitrosyl hydrides and cations of Group VI transition metals

Oxley, Jimmie Carol January 1983 (has links)
The novel bimetallic hydrides [(n⁵-C₅H₅)W(N0)IH]₂ and [(n⁵-C₅H₅)W(N0)H₂]₂ can be prepared sequentially by the metathesis of [(n⁵-C₅H₅)W(N0)IH₂]₂ with Na[H₂Al(0CH₂CH₂0CH₃)₂]. Analyses of the ¹H NMR spectra of C[(n⁵-C₅H₅)W(N0)IH]₂ and [(n⁵-C₅H₅)W(N0)IH₂]₂ show the former contains hydride ligands bound to tungsten in a terminal fashion, while the latter possesses two terminal and two bridging hydrides. Addition of a Lewis base to [(n⁵-C₅H₅)W(N0)IH]₂ results in the formation of hydride species (n⁵-C₅H₅)W(N0)IHL (L = P(0Ph)₃, P(0Me)₃, PPh₃); in like manner, the dimer [(n⁵-C₅H₅)W(N0)IH₂]₂ is cleaved by triphenylphosphite to form the monomer cis or trans [(n⁵-C₅H₅)W(N0)IH₂[P(0Ph)₃]. A comparison is made of the reactivity of the tungsten-hydrogen link in the nitrosyl hydrides (n⁵-C₅H₅)- W(N0)IH[P(0Ph)₃], (n⁵-C₅H₅)W(N0)₂H, and (n⁵-C₅H₅)W(N0)IH₂[P(0Ph)₃]. The Mo(N0)₂²⁺ unit is obtained as the tetrakis-solvate via chloride abstraction from Mo(N0)₂Cl₂ by AgBF₄ or nitrosylation of Mo(C0)₆ by NOPF₆ in coordinating solvents such as nitromethane, acetonitrile, or tetrahydro-furan. The unsolvated complex [Mo(N0)₂(PF₆)₂][aub=n] is produced if the latter reaction is performed in dichloromethane; however, it readily converts to [Mo(N0)₂S₄](PF₆)₂ upon exposure to coordinating solvents (S). Hard Lewis bases (L = CH₃CN , 0PPh₃ or L₂ = 2 ,2-bipyridine replace the solvent molecules in [Mo(N0)₂S₄]X₂ (X = BF₄⁻, PF₆⁻) forming complexes [Mo(N0)₂L₄]²⁺ or [Mo(N0)₂L₂S₂]²⁺ depending upon the solvent employed. Reagents capable of being oxidized appear to reduce the dinitrosyl dication without permanent coordination to the molybdenum centre. Reduction of [Mo(NO)₂S₄](PF₆)₂ or [Mo(N0)₂(PF₆)₂][sub=b] is effected by sodium amalgam (one equivalent); addition of a ligand L₂ (L₂ = 2,2-bipyridyl, 3,4,7,8-tetramethyl-1,1O-phenanthroline) to the reaction mixture permits the isolation of [M(NO)₂L₂]₂(PF₆)₂. Addition of excess ligand results in the formation of non-nitrosyl containing species [Mp(L₂)₃]PF₆ (L = 0PPh₃ or L₂ = 3,4,7,8-tetramethyl-1 ,10-phenanthro- line). Decomposition of the nitrosyl species results from attempts to reduce [Mo(NO)₂S₄]²⁺ by two electrons. New complexes are identified by the aid of IR and ¹H, ¹⁹F, or ³¹P NMR spectroscopy and conductance measurements. Attempts to prepare thionitrosyl analogues of [Mo(N0)₂L₄]²⁺ have met with limited success; the only wel1-characterized thionitrosyls isolated in this study are the known (n⁵-C₅H₅)Cr(C0)₂NS and the new [(n⁵-C₅H₅)Mo-(N0)(NS)PPh₃]BF₄. Also discussed is the interaction of NOPF₆ with solvents. NOPF₆ has been found to react slowly with acetonitrile, a common solvent for nitro-sonium salts. / Science, Faculty of / Chemistry, Department of / Graduate
40

Planar, square-pyramidal, and macrocyclic transition metal complexes prepared form linear tetradentate diaminediphosphine ligands /

Scanlon, Lawrence George January 1981 (has links)
No description available.

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