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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.
21

New chemistry with gold-nitrogen complexes: synthesis and characterization of tetra-, tri-, and dinuclear gold(I) amidinate complexes. Oxidative-addition to the dinuclear gold(I) amidinate

Abdou, Hanan Elsayed 02 June 2009 (has links)
Nitrogen ligands have been little studied with gold(I) and almost no chemistry has been described using anionic bridging nitrogen ligands. This dissertation concerns the impact of the bridging ligands amidinate, ArNHC(H)NAr, on the chemistry of gold(I) and, in particular, the effect of substituents on the molecular arrangement. The electronic vs. steric effect of the substituents on the molecular arrangement of gold(I) amidinates complexes is studied in detail. Tetra-, tri-, and dinuclear gold(I) amidinate complexes are synthesized and characterized using X-ray diffraction. Spectroscopic and electrochemical studies of the amidinate complexes are described. Catalytic studies suggest that gold amidinates and related gold nitrogen complexes are the best catalyst precursors for CO oxidation on TiO2 surface reported to date (87% conversion). The dinuclear gold(I) amidinate complex with a Auâ ¦Au distance of 2.711(3) Ã is rare. To our knowledge, there is only one other example of a symmetrical dinuclear gold(I) nitrogen complex. Oxidative-addition reactions to the dinuclear gold(I) complex, [Au2(2,6-Me2-form)2] are studied in detail and result in the formation of gold(II) complexes. The gold(II) amidinate complexes are the first formed with nitrogen ligands. The complexes are stable at room temperature. Mixed ligand tetranuclear gold(I) clusters and tetranuclear mixed Au-Ag metal clusters of pyrazolate and amidinate ligands are synthesized and characterized using Xray diffraction.
22

An Investigation of the Wake behind Single Cylinder under Momentum Interference Using PIV

Chen, Hua-Feng 03 July 2003 (has links)
Particle image velocimetry was widely used in many kinds of flow field recently. It provides a global view of instantaneous fluid velocity without disturbs flow field. In the present study, the cylinder wake with momentum addition was measured by PIV. The Reynolds number was fixed at 465 and 535 with cylinder diameter 19mm. The flow¡¦s displacement was measured by tracking flow images of 50 diameter ployamid 12 particles. The mean velocity of the momentum interference from the cylinder surface were 21 and 52 mm/s, respectively. From the results, the wake region shrinks under momentum injection at 0˚, but enlarges at 30˚ to 90˚. Under momentum suction, the effect of the wake expands at 0˚. Although the down stream velocity becomes more uniform at 30˚ and 60˚, the wake region spreads when suction at 90˚. On the other hand, the velocity spectra by hot-film anemometry also give consistent results with PIV analysis.
23

Addition and substraction strategies : assessment and instruction /

Timmermans, Rudolf Eduard, January 1900 (has links)
Doctoral thesis--Social sciences--Radboud university Nijmegen, 2005. / Notes bibliogr.
24

Addition of nucleophiles to [([eta]-diene)Co(CO)]BF complexes /

Barinelli, Lucio Salvatore, January 1988 (has links)
Thesis (Ph. D.)--University of Oklahoma, 1988. / On t.p. [eta] is represented by the Greek letter. Includes bibliographical references.
25

Emulsion copolymerization in continuous reactors

Mead, Richard Norman 12 1900 (has links)
No description available.
26

The role of repression in the pathogenesis of alcoholism

Martin, Colin January 1996 (has links)
No description available.
27

Chronometric analysis of mental addition

Mulhern, Gerard A. M. January 1985 (has links)
No description available.
28

A study of a polyethylene ionomer :

Gao, Yan Unknown Date (has links)
Thesis (PhDAppliedScience)--University of South Australia, 2003.
29

A study of a polyethylene ionomer :

Gao, Yan Unknown Date (has links)
Thesis (PhDAppliedScience)--University of South Australia, 2003.
30

Investigations into the effects of chain-length-dependent termination and propagation on the kinetics of radical polymerisation : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry, University of Canterbury /

Smith, Gregory Brian. January 1900 (has links)
Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). "First submitted June 2007. Final version January 2008." Includes bibliographical references. Also available via the World Wide Web.

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