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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

SPECTROSCOPIC CHARACTERIZATION OF THE POLYMORPHISM OF VANADYL AND CHLORO-GALLIUM PHTHALOCYANINE

Sims, Tabitha Dee, 1960- January 1987 (has links)
The investigation of the polymorphism of tri- and tetravalent phthalocyanine (Pc) species containing an axial ligand has been the focus of this work. The polymorphic nature of these nonplanar Pcs results in unique packing arrangements in the solid state, which affect the spectral and conductive properties of thin films generated with these materials. The goal of this work was to isolate and identify the various phases formed by vanadyl and chloro-gallium Pcs, establish a correlation between surface morphology, vibrational and absorption spectra and crystalline arrangement and further the understanding of the molecular structure of each phase. Block and platelet morphologies were observed for both Pc species. A correlation between the morphology and several phase sensitive peaks in the vibrational and visible absorption spectra was established. It was shown that the block/prism morphology corresponds to a cofacially bridged structure and the platelet phase consists of a slip-stacked arrangement.
2

Effects of substituents on the photosensitizing and electrocatalytic properties of phthalocyanines

Maree, Suzanne Elizabeth January 2002 (has links)
In this work a selection of octasubstituted phthalocyaninato Zinc, Ge(IV) and Sn(IV) complexes were synthesized for possible use in photodynamic therapy and their photochemistry, photophysics and electrochemistry studied. Third-generation complexes containing steroids, e.g. cholesterol and estrone, were synthesized to improve tumour selectivity. The zinc phthalocyanine complexes (ZnPc) showed that complexes containing electron-donating groups have higher photostability. Germanium phthalocyanine complexes (GePc) undergo phototransformation rather than direct photobleaching and the tin phthalocyanine complexes (SnPc) undergo photobleaching mediated by photoreduction of the phthalocyanine ring. Singlet oxygen production showed increased in the following order: GePc>SnPc>ZnPc. Triplet lifetimes of the GePc (168-340μs) are very similar to that of the ZnPc (197 - 366μs), but the triplet lifetimes of the SnPc are ten fold shorter (10 - 32μs ). Triplet quantum yields are higher for the GePc (0.20 - 0.50) and SnPc (0.08 - 0.45) than for the ZnPc (0.02 - 0.25). Fluorescence lifetimes of GePc ( 4.0 - 5.1 ns) are significantly longer than that of ZnPc (1.9 - 3.0 ns) and SnPc (0.2 - 0.4 ns). Fluorescence quantum yields decrease in the following order: GePc(0.21-0.31)>ZnPc(0.02-0.21)>SnPc(0.02- 0.06). Ring-substituted cobalt phthalocyanine complexes of the form CoPc(R)4 (R= NH2, N02, C(CH3)3, S03H and COOH) are compared for their catalytic activities towards the oxidation of cysteine. The potential for the electrocatalytic oxidation of cysteine is closely related to the Com/Co11 couple of the CoPc(R)4 complexes in acidic media and to the Con/Co1 couple in basic media. The catalytic current and the oxidation potential for cysteine are dependent on the pH of the solution, the potential becoming less positive and the currents increasing with increase in pH.
3

Synthesis of multi-neopentoxy substituted and non-centrosymmetric phthalocyanines

Bhardwaj, Namrta. January 2001 (has links)
Thesis (Ph. D.)--York University, 2001. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references (leaves 134-141). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ67891.
4

Studies of phthalocyanine-containing polymers. / CUHK electronic theses & dissertations collection

January 2003 (has links)
Lee Pui Sze Priscilla. / "October 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
5

The synthesis, characterization and electrochemical parametrization of several chromium phthalocyanine and porphyrin derivatives /

Alexiou, Christos. January 2003 (has links)
Thesis (M.Sc.)--York University, 2003. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references (leaves 88-91). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ99270
6

Analysis of dyes and diode-laser-based detector development in capillary electrophoresis

Williams, Stephen John January 1993 (has links)
No description available.
7

Synthetic studies of substituted 2,3-naphthalocyaninatozinc(II) complexes.

January 1997 (has links)
by Yee-On Yeung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 76-80). / Acknowledgment --- p.i / Contents --- p.ii / List of Figures --- p.v / List of Tables --- p.vi / Abbreviations --- p.vii / Abstract --- p.viii / Chapter 1. --- Introduction --- p.1 / Chapter 2. --- Results and Discussion / Chapter 2.1 --- "Synthesis of Differently Substituted 2,3-Naphthalocyaninatozinc(II) Complexes" / Chapter 2.1.1 --- Preparation of substituted dicyanonaphthalenes --- p.13 / Chapter 2.1.2 --- "Preparation of octasubstituted 2,3-naphthalocyaninatozinc(II) complexes" --- p.16 / Chapter 2.1.3 --- "Aggregation of octasubstituted 2,3-naphthalocyaninatozinc(II) complexes" --- p.27 / Chapter 2.1.4 --- "Effects of substituents on the electronic spectra of 2,3- naphthalocyaninatozinc(II) complexes" --- p.31 / Chapter 2.2 --- "Synthetic Studies of Liquid Crystals Based on a 2,3-Naphthalocyanine Core" / Chapter 2.2.1 --- Preparation of dicyanonaphthalenes substituted with long side chains --- p.34 / Chapter 2.2.2 --- "Preparation of liquid crystals based on 2,3-naphthalocyanine cores" --- p.36 / Chapter 2.2.3 --- Characterization of the liquid crystals --- p.42 / Chapter 2.3 --- Conclusions --- p.46 / Chapter 3. --- Experimental Section / Chapter 3.1 --- Materials --- p.47 / Chapter 3.2 --- Physical Measurements --- p.47 / Chapter 3.3 --- "Preparation of (1,6,10,15,19,24,28,33-octamethyl-2,3-naphthalocyaninato)- zinc(II) (62)" --- p.48 / Chapter 3.4 --- "Preparation of (1,6,10,15,19,24,28,33-octahexyl-2,3-naphthalocyaninato)- zinc(II) (63)" --- p.51 / Chapter 3.5 --- "Preparation of (2,5,11,14,20,23,29,32-octahexyl-1,6,10,15,19,24,28,33- octamethyl-2,3-naphthalocyaninato)zinc(II) (67)" --- p.54 / Chapter 3.6 --- "Preparation of (2,5,11,14,20,23,29,32-octahexy1-2,3-naphthalocyaninato- zinc(II)complex (64)" --- p.58 / Chapter 3.7 --- "Preparation of (3,4,12,13,21,22,30,31-octapropylthio-2,3- naphthalocyaninato)zinc(II) (65)" --- p.60 / Chapter 3.8 --- "Preparation of (3,4,12,13,21,22,30,31 -octaphenylthio-2,3- naphthalocyaninato)zinc(II) (66)" --- p.63 / Chapter 3.9 --- "Preparation of [2,5,11,14,20,23,29,32-octa(hexyloxymethyl)-2,3- naphthalocyaninato]zinc(II) (79)" --- p.64 / Chapter 3.10 --- "Preparation of [2,5,11,14,20,23,29,32-octa(methoxybutyl-digol)-2,3- naphthalocyaninato]zinc(II) (80)" --- p.68 / Chapter 3.11 --- "Preparation of [2,5,11,14,20,23,29,32-octa(dodecylthiomethyl)-2,3- naphthalocyaninato]zinc(II) (81)" --- p.70 / Chapter 3.12 --- "Preparation of [3,4,12,13,21,22,30,31 -octa(octylthio)-2,3- naphthalocyaninato]zinc(II) (82)" --- p.72 / Chapter 3.13 --- "Preparation of [3,4,12,13,21,22,30,31-octa(dodecylthio)-2,3- naphthalocyaninato]zinc(II) (83)" --- p.74 / References --- p.76 / "Appendix A IR spectra of octasubstituted ZnNc complexes (62, 63, 64,66)." --- p.81 / Appendix B Mass spectra of octasubstituted ZnNc complexes (63-66). --- p.85 / Appendix C Determination of aggregation number (n) and aggregation constant (K). --- p.89 / Appendix D 1H NMR spectra of octasubstituted ZnNc complexes (80,81,83). --- p.90 / "Appendix E 13C NMR spectra of octasubstituted ZnNc complexes (80,82, 83)." --- p.93
8

Organic optoelectronic materials optical properties and 1D nanostructure fabrication /

Tong, Wing-yun. January 2006 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.
9

Polyalkynyl phthalocyanines

Suchozak, Bohdan Bob. January 1999 (has links)
Thesis (M. Sc.)--York University, 1999. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references (leaves 81-85). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ56207.
10

Synthesis and characterization of octa substituted phthalocyaninatopolysiloxanes

Du, Aiguo January 2000 (has links)
No description available.

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