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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.
11

Synthesis, structure and magnetism in clusters and networks containing dicyanamide and related ligands

Price, David James, 1976- January 2003 (has links)
Abstract not available
12

Structural aspects of bis(quadridentate)zirconium(IV) complexes. Ligand motion and ligand exchange behavior of bis(N, N'-disalicylidene-1,2-phenylenediamino)zirconium(IV) and the two new complexes bis(N, N'-disalicylidene-cis-1,2-diamino-cyclohexane)-zirconium(IV) and bis(N, N''-disalicylidene-trans-1,2-diaminocyclhexane)zirconium(IV) /

Cleary, Brian P. January 1989 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1989. / "Reference": leaves 224-227.
13

Inorganic polymers (geopolymers) as potential bioactive materials : a thesis submitted to the Victoria University of Wellington in fulfilment of the requirements for the degree of Master of Science in Chemistry /

Rahner, Nils. January 2009 (has links)
Thesis (M.Sc.)--Victoria University of Wellington, 2009. / Includes bibliographical references.
14

Hydrothermal synthesis of metal carboxylate polymers using high coordination number metals /

Tse, Hiu Wah. January 2004 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references. Also available in electronic version. Access restricted to campus users.
15

Synthesis and thermal treatment of lithium- and magnesium-containing geopolymers : a thesis submitted to the Victoria University of Wellington in partial fulfilment of the requirements for the degree of Master of Science in Chemistry /

O'Connor, Sean James. January 2009 (has links)
Thesis (M.Sc.)--Victoria University of Wellington, 2009. / Includes bibliographical references.
16

Hydrothermal synthesis of metal coordination polymers using mixed pyridine-carboxylate ligands /

Lin, Zhuojia. January 2005 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references. Also available in electronic version.
17

Synthesis, characterization, electrochemistry, and ring-opening polymerization of heavier group 13 bridged metallocenophanes

Schachner, Joerg Anton 30 August 2007
The synthesis of two types of metallocenophanes is described: strained, ring-tilted [1]metallocenophanes with Al and Ga in bridging positions and Fe and Ru as transition elements and unstrained [1.1]ferrocenophanes with Al, Ga and In in bridging positions. [1]Metallocenophanes are potential monomers for the synthesis of organometallic polymers via ring-opening polymerization (ROP). After the successful synthesis of various starting monomers using the concept of intramolecular coordinating ligands, four different pathways of ROP were investigated. However, only one of these pathways proved successful in obtaining polymeric material. The starting monomers showed a surprising stability against commonly used initiators. This was attributed to an overly steric protection by the intramolecular coordinating ligands, thereby blocking the initiators, and a reduced ring strain, a consequence of the size of the bridging element.<p>[1.1]Ferrocenophanes belong to a class of dinuclear complexes where the two redox-active iron atoms are in close proximity with restricted flexibility. [1.1]Ferrocenophanes with Al, Ga and In in bridging positions were investigated. The redox properties of previously published [1.1]ferrocenophanes showed a fully reversible, stepwise, one-electron oxidation (FeII/FeII → FeII/FeIII → FeIII/FeIII). After the initial oxidation of the first iron center, a stable, mixed-valent monocationic species is created. The removal of a second electron from the second iron center therefore is more difficult, and occurs at higher potential to create the dicationic species. The difference in potential for the stepwise oxidation is directly related to the delocalization of the charge in the mixed-valent species. This delocalization mainly depends on the electronic properties of the bridging element. Depending on the bridging group 13 element, very different electrochemical properties were observed. For the alumina[1.1]ferrocenophane, no delocalization was detected, and a one-step, two-electron oxidation at the same potential was observed. For the inda[1.1]ferrocenophane, a more complex electrochemistry was observed that we attributed to an isomerization of the compound in solution. Only the investigated galla[1.1]ferrocenophane showed the expected stepwise oxidation-reduction behavior.
18

Synthesis, characterization, electrochemistry, and ring-opening polymerization of heavier group 13 bridged metallocenophanes

Schachner, Joerg Anton 30 August 2007 (has links)
The synthesis of two types of metallocenophanes is described: strained, ring-tilted [1]metallocenophanes with Al and Ga in bridging positions and Fe and Ru as transition elements and unstrained [1.1]ferrocenophanes with Al, Ga and In in bridging positions. [1]Metallocenophanes are potential monomers for the synthesis of organometallic polymers via ring-opening polymerization (ROP). After the successful synthesis of various starting monomers using the concept of intramolecular coordinating ligands, four different pathways of ROP were investigated. However, only one of these pathways proved successful in obtaining polymeric material. The starting monomers showed a surprising stability against commonly used initiators. This was attributed to an overly steric protection by the intramolecular coordinating ligands, thereby blocking the initiators, and a reduced ring strain, a consequence of the size of the bridging element.<p>[1.1]Ferrocenophanes belong to a class of dinuclear complexes where the two redox-active iron atoms are in close proximity with restricted flexibility. [1.1]Ferrocenophanes with Al, Ga and In in bridging positions were investigated. The redox properties of previously published [1.1]ferrocenophanes showed a fully reversible, stepwise, one-electron oxidation (FeII/FeII → FeII/FeIII → FeIII/FeIII). After the initial oxidation of the first iron center, a stable, mixed-valent monocationic species is created. The removal of a second electron from the second iron center therefore is more difficult, and occurs at higher potential to create the dicationic species. The difference in potential for the stepwise oxidation is directly related to the delocalization of the charge in the mixed-valent species. This delocalization mainly depends on the electronic properties of the bridging element. Depending on the bridging group 13 element, very different electrochemical properties were observed. For the alumina[1.1]ferrocenophane, no delocalization was detected, and a one-step, two-electron oxidation at the same potential was observed. For the inda[1.1]ferrocenophane, a more complex electrochemistry was observed that we attributed to an isomerization of the compound in solution. Only the investigated galla[1.1]ferrocenophane showed the expected stepwise oxidation-reduction behavior.
19

Solid-gel interactions in geopolymers

Lee, William K. January 2002 (has links) (PDF)
This is partly because the requirements for such an ultimate material change with people’s perception about its properties as well as its environmental impact. Thus, the once-believed ultimate Portland cement binder is now becoming unacceptable for a number of reasons including poor durability as well as severe environmental impact during production. Thus, an improved mineral binder is required by modern society to serve the same purposes as the existing Portland cement binder, as well as to reduce the current environmental impact caused by Portland cement production. / Geopolymerisation is such a ‘green’ technology capable of turning both natural ‘virginal’ aluminosilicates and industrial aluminosilicate wastes, such as fly ash and blast furnace slag, into mechanically strong and chemically durable construction materials. However, the source materials for geopolymer synthesis are less reactive than Portland cement clinkers and the chemical compositions of these source materials can vary significantly. Consequently, product quality control is a major engineering challenge for the commercialisation of geopolymers. / This thesis is therefore devoted to the mechanistic understanding of the interfacial chemical interactions between a number of natural and industrial aluminosilicates and the various activating solutions, which govern the reactivity of the aluminosilicate source materials. The effects of activating solution alkalinity, soluble silicate dosage and anionic contamination on the reactivity of the aluminosilicate source materials to produce geopolymeric binders, as well as their bonding properties to natural siliceous aggregates for concrete making, are examined. In particular, a new set of novel ‘realistic’ reaction models has been developed for such purposes. These reaction models have been further utilised to develop a novel analytical procedure, which is capable of studying geopolymerisation on ‘real’ geopolymers in situ and in real time. This novel procedure is invaluable for the total understanding of geopolymerisation, which is in turn vital for effective geopolymer mix designs.
20

Solid-gel interactions in geopolymers /

Lee, William K. January 2002 (has links)
Thesis (Ph.D.)--University of Melbourne, Dept. of Chemical Engineering, 2003. / Typescript (photocopy). Includes bibliographical references.

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