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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.
1

A comparison of ultraviolet, thermal, and microwave polymerized acrylamide terminated polydimethylsiloxane /

Hall, Grace Louise. January 1993 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 89-92). Also available via the Internet.
2

Guanidinium linked oligomers : design, synthesis, and applications /

Schneider, Stephen Edward, January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Available also in a digital version from Dissertation Abstracts.
3

The synthesis of 1-butene oligomers with vinyl endgroups and their use in further reactions /

Al-Aeeb, Ahmed January 2007 (has links)
Thesis (MSc)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.
4

Towards polyhydroxylated nylon and cyclopeptide-cyclodextrin analogues

Mayes, Benjamin A. January 2003 (has links)
No description available.
5

Synthesis, characterization and properties of metallodendrimers.

January 1995 (has links)
by Ida Yuk-Kit Chan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 58-61). / Contents --- p.i / Acknowledgments --- p.ii / Abstract --- p.iii / Abbreviations --- p.iv / Chapter Chapter I. --- Introduction / Chapter 1. --- General background of dendrimers --- p.1 / Chapter 2. --- Metallodendrimers --- p.4 / Chapter 3. --- "General background of 2,2':6',2""-terpyridine complex" --- p.9 / Chapter Chapter II. --- Synthesis and Characterization / Chapter 1. --- Structure of the dendritic ligand --- p.13 / Chapter 2. --- Synthesis of the terpy-based metallodendrimers --- p.14 / Chapter 3. --- Characterization --- p.23 / Chapter Chapter III. --- Properties of Metallodendrimers / Chapter 1. --- Solubility and physical appearance --- p.29 / Chapter 2. --- UV-visible light absorption studies --- p.30 / Chapter 3. --- X-ray photoelectron spectroscopy --- p.33 / Chapter 4. --- Cyclic voltammetry studies --- p.36 / Chapter Chapter IV. --- Summary --- p.42 / Chapter Chapter V. --- Experimental --- p.43 / References --- p.58 / Spectra --- p.62
6

Synthesis and properties of optically active, axially chiral oligomers.

January 1996 (has links)
by Man-Kit Ng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 60-69). / Contents --- p.i / Acknowledgments --- p.ii / Publications --- p.iii / Abstract --- p.iv / Abbreviations --- p.v / Chapter 1. --- Introduction / Chapter 1.1 --- General Background of Optically Active Polymers and Oligomers --- p.1 / Chapter 1.2 --- Optically Active Conjugated Polymers with Main Chain Chirality --- p.6 / Chapter 1.3 --- Optically Active Oligomers with Main Chain Chirality --- p.8 / Chapter 2. --- Design of Optically Active Oligomers with Main Chain Chirality / Chapter 2.1 --- Structure of the Oligomers --- p.11 / Chapter 2.2 --- Selection of Chiral Element --- p.11 / Chapter 2.3 --- Selection of Spacer Linkage --- p.13 / Chapter 3. --- Synthetic Routes to Optically Pure l,l'-Bi-2-naphthols / Chapter 3.1 --- Asymmetric Synthesis --- p.16 / Chapter 3.2 --- "Synthesis and Optical Resolution of l,l'-Bi-2-naphthols" --- p.19 / Chapter 4. --- Synthesis and Characterization of Optically Active Binaphthol-based Oligomers / Chapter 4.1 --- Synthesis of Enantiomerically Pure Monomer41 --- p.23 / Chapter 4.2 --- Oligomerization of the Monomer41 --- p.33 / Chapter 4.3 --- Characterization of Binaphthol-based Oligomers 41 -44 --- p.35 / Chapter 5. --- Properties of Optically Active Oligomers 41 - --- p.44 / Chapter 5.1 --- Physical Appearance and Solubility Property --- p.40 / Chapter 5.2 --- Ultraviolet Spectroscopy --- p.40 / Chapter 5.3 --- Polarimetry Studies --- p.42 / Chapter 5.4 --- Circular Dichroism Studies --- p.43 / Chapter 5.5 --- Cyclic Voltammetric Studies --- p.45 / Chapter 6. --- Conclusions --- p.48 / Chapter 7. --- Experimental --- p.49 / References --- p.60 / Spectra --- p.70
7

Synthesis and structure-property relationships of novel multi-[pi] conjugated molecular systems

Lo, Pik Kwan Peggy 01 January 2006 (has links)
No description available.
8

An investigation of polaron, bipolaron and exciton structures in oligothiophenes : a resonance raman and theoretical study

Clarke, Tracey Michelle, n/a January 2007 (has links)
This thesis presents a spectroscopic and computational study of a variety of substituted oligothiophenes. The purpose of this study was to elucidate the structural properties of their neutral, oxidised and excited states. This was accomplished using a number of spectroscopic methods, including electronic absorption, resonance Raman and fluorescence spectroscopy. Analysis of the data provided by these methods was aided by the application of density functional theory (DFT) to the neutral and charged species, allowing conclusions regarding bond length changes and molecular orbitals to be drawn. Advancing the understanding of the structural properties of conductive materials such as oligothiophenes is important due to their potential application in plastic electronic devices (organic solar cells, field effect transistors and light emitting diodes, for instance) and the need to clarify the charge transport mechanism. The compounds examined in this thesis are primarily based on 3� styryl-substituted terthiophene. Substituted derivatives of this molecule include those with groups on the para position of the phenyl ring or methyl α,α� end caps. Larger ethenyl-aryl groups were also investigated, as were analogous thiophenes and sexithiophenes. Indeed, the 3�-substituted sexithiophenes formed an integral part of this investigation since they rapidly form in the head-to-head orientation from the oxidation and consequent [sigma]-dimerisation of the substituted terthiophenes. DFT calculations on the sexithiophene charged species have indicated the presence of a full polaronic or bipolaronic structural defect in the centre of the thiophene backbone, as defined by the reversal of the CC bond length alternation to create a domain of quinoidal bond sequence. However, the structural defect of the styryl sexithiophenes is more strongly localised than that observed for unsubstituted sexithiophene; indeed, the charged defect appears to be confined by the positions of the styryl substituents. This defect confinement along the thiophene backbone is particularly apparent in the styryl sexithiophene dications. Electronic absorption and resonance Raman spectroscopy have been applied to the oxidation products of the styryl terthiophenes. Only sexithiophene charged species are observed when the α termini are unsubstituted; these include sexithiophene radical cations, [pi]-dimers (a stabilising face-to-face interaction between two radical cations) and dications. The resonance Raman spectra of these charged species are characterised by a very intense symmetrical CC stretching mode of the thiophene inter-ring bonds, which is also evident in the theoretical spectra. The extensive differences between the styryl and unsubstituted sexithiophene dication Raman spectra have been attributed to defect confinement: the strongest Raman band of the unsubstituted sexithiophene dication is due to a vibrational mode localised over the entire sexithiophene backbone while that of the styryl sexithiophenes is localised over the central two thiophene rings - the same area occupied by the confined defect. A combined steady-state and picosecond time-resolved emission study on the styryl terthiophenes revealed that by judicious choice of the para R group in styryl terthiophenes it is possible to tune the nature of the first excited singlet state from [pi],[pi]* to charge transfer character. Charge transfer states may offer possible strategies for solar cells in which charge separation is a key step.
9

Chemical amplification via template-directed synthesis on DNA /

Zhan, Zheng-Yun James. January 1997 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Chemistry, December 1997. / Includes bibliographical references. Also available on the Internet.
10

Synthesis and conformational studies of beta 2,3-cyclic aminoxy peptides

Hao, Yu, January 2005 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

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