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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.
211

Synthetic and biosynthetic studies on nitrogen heterocycles

MacKinnon, John W. M. January 1976 (has links)
No description available.
212

Studies in 2-naphthol derivatives

Marks, Robert Barras January 1976 (has links)
No description available.
213

Matrix isolation studies of some group VI and group VII substituted metal carbonyl complexes

McHugh, Terence Michael January 1980 (has links)
No description available.
214

Synthesis and catalytic applications of ruthenium- and iron-based nanoparticles from the pyrolysis of metal-containing homopolymers and block copolymers

Erhard, Felix Maria Maximilian January 2012 (has links)
This Thesis is concerned with the synthesis of new Fe- and Rucontaining homopolymers and block copolymers and their applications as precursors for the fabrication of catalytically active nanoparticles upon pyrolysis (NPs). The strained sila[l]ferrocenophane (T]-CSH4) Fe(T]-CsH4)SiMeRc has been synthesised. Two different routes for its synthesis Were employed and compared. The compound was polymerised via thermal ringopening polymerisation (ROP), which afforded insoluble polymeric material. Photo controlled ROP. was used to afford narrowly dispersed, high molecular . weight (Mn between 10,000 and 53,000 Da) air and moisture stable [(T]CsH4) Fe(T]-CsH4)-SiMeRc]n. Electrochemical characterisation of (T]-CsH4)Fe(T]CsH4)- SiMeRc revealed unusual, concentration dependent behaviour associated with the pendant Rc substituent. We postulate a dimerisation pathway based on Ru-Ru bond formation upon oxidation of the Rc side . groups. The synthesis of the block copolymer PSm-b-[(T]-CsH4)Fe(T]-CsH4)SiMeRc] n was carried out and afforded narrowly dispersed block copolymers of high molecular weight (Mn between 28,000 and 36,000 Da). The synthesis of Fe(T]-CsH4)zSi(Me)(C=CSiMe3) and its photocontrolled polymerisation to yield high molecular weight (Mn between 13,000 and 45,500 Da) [Fe(T]-CsH4)zSi(Me)(C=CSiMe3)]n is also presented. Deprotection and clusterisation with RU3(CO)12 yielded the highly metalen, riched compound [Fe( T]-CsH4)zSiCH3{(Il-H)Ru3(CO)9Cz}]n. UV -irradiation was utilised for cross-linking reactions, which proceeded readily. The block copolymers PSm-h-[Fe(T]-CsH4)zSi(Me)(C=CSiMe3)]n and PSm~h-[Fe(T]CsH4) zSiCH3{(Il-H)Ru3(CO)9CZ}]n were prepared. The fabrication of metal-containing nanoparticles (NPs) via pyrolysis of the metallopolymers was carried out via bulk' and thin film pyrolysis between 500 and 1000°C. Analysis of the resulting materials revealed the formation of RuSi, RuzFeSi, RU4Fe and/or Ru NPs, depending on the material and pyrolysis temperature. The particles were embedded in a carbonaceous matrix. The catalytic activity towards hydrogenation of cyclohexene by the particles formed via pyrolysis of thin films was investigated and showed some catalytic activity. The synthesis of a metallopolymer for the fabrication of monometallic Ru NPs is also discussed.
215

An investigation of a non-empirical molecular orbital method : theoretical studies of electrophilic aromatic substitution

McConkey, Frederick William January 1975 (has links)
No description available.
216

Some aspects of group III B alkoxide chemistry

Oliver, John Geoffrey January 1969 (has links)
No description available.
217

Studies in the acylation of adenosine and related systems : the synthesis of N6 carbamoyl-adenosine derivatives

Lyon, Patricia Anne January 1974 (has links)
No description available.
218

The biosynthesis of aporphine alkaloids

McHugh, John Lawrence January 1971 (has links)
No description available.
219

Synthesis in the pseudouridine series

Ogden, Richard Charles January 1977 (has links)
No description available.
220

Synthetic studies in the steriod and cytochalasan fields

Owens, Christopher January 1977 (has links)
No description available.

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