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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.
181

Nanostructured optical fibre for use as miniature surface-enhanced raman scattering sensors

White, Daniel Joshua. January 2008 (has links)
Thesis (PhD) - Swinburne University of Technology, Centre for Atom Optics and Ultrafast Spectroscopy, 2007. / Thesis submitted in fulfilment for the degree of Doctor of Philosophy, Centre for Atom Optics and Ultrafast Spectroscopy, Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, 2008. Typescript. Bibliography: p. 151-160.
182

Resonance Raman studies of isotopically labeled heme proteins

Rwere, Freeborn. January 2009 (has links)
Thesis (Ph. D.)--Marquette University, 2009. / James R. Kincaid, Daniel Sem, Michael D. Ryan, Advisors. Access available to Marquette University only.
183

Characterization of planar defects in silicon carbide nanowires

Wieligor, Monika Katarzyna. January 2010 (has links) (PDF)
Thesis (Ph.D.)--Texas Christian University, 2010. / Title from dissertation title page (viewed May 4, 2010). Includes abstract. Includes bibliographical references.
184

Optical properties of ZnO thin film : raman spectroscopy, optical reflection, photoluminescence and stimulated emission /

Xie, Xing. January 2005 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 82). Also available in electronic version.
185

Time-resolved resonance Raman and density functional theory study of the photophysical and photochemical processes involved in the photoinduced deprotection reaction of the p-hydroxyphenacyl acetate phototrigger compound and its p-hydroxyacetophenone model compound

Zuo, Peng. January 2005 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
186

Carrier concentration determination in GaMnAs by optical techniques /

Wang, Jie. January 2006 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references (leaves 64-66). Also available in electronic version.
187

Surface-enhanced hyper raman and surface-enhanced raman scattering : novel substrates, surface probing molecules and chemical applications /

Xie, Yu-Tao. January 2007 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references. Also available in electronic version.
188

Μελέτη του μοριακού προσανατολισμού συμπολυμερών πολυ(ναφθαλενικού γλυκολεστέρα) / πολυ (τερεφθαλικού γλυκολεστέρα με τη χρησιμοποίηση πολυμερών φασμάτων Raman και διχροϊσμό κατοπτρικής ανακλαστικότητας στο υπέρυθρο

Soto Beobide, Amaia 07 July 2010 (has links)
- / -
189

"Έξυπνα" σύνθετα υλικά πολυμερικής μήτρας με ενσωματωμένα σύρματα με μνήμη σχήματος

Μπόλλας, Δημήτριος 27 August 2010 (has links)
- / -
190

Estudo de aspectos do comportamento fotoquímico e eletroquímico de hidrocarbonetos policíclicos aromáticos / Study of aspects of the photochemist and electrochemical behavior of aromatical policíclicos hydro-carbons

Denise de Sales Cordeiro 15 September 2006 (has links)
Uma classe de compostos presente no material particulado atmosférico que desperta particular interesse e constitui-se em motivo de preocupação são os chamados hidrocarbonetos policíclicos aromáticos (HPA). Estes caracterizam-se por possuir dois ou mais anéis aromáticos condensados e são formados pela queima de combustíveis orgânicos na presença de quantidade limitada de oxigênio. Além dos próprios HPA, são importantes, sob o ponto de vista ambiental, seus derivados nitrados e oxigenados. Sua identificação e quantificação são passos importantes no processo de se esclarecer os mecanismos que conduzem à formação desses derivados. Neste trabalho, estudou-se reações fotoquímicas de HPA e nitro-HPA adsorvidos sobre o fotocatalisador dióxido de titânio (TiO2) ou sobre sílica (SiO2) através de técnicas de espectroscopia Raman. Foram conduzidos também estudos espectroeletroquímicos dos HPA através de espectroscopia eletrônica e Raman intensificada (efeito SERS) visando a caracterização vibracional dos produtos de processos faradáicos desses compostos sobre eletrodos, para comparação com os produtos de fotodegradação. Os HPA estudados foram: antraceno, 9-nitroantraceno, fenantreno, fluoreno, fluoranteno, pireno e criseno. Para o estudo das reações fotoquímicas foi feita uma pré-adsorção dos diversos HPA e nitro-HPA sobre TiO2 ou SiO2, que foram então irradiados em 254 nm em intervalos de tempo pré-determinados. Verificou-se mudanças nas estruturas das moléculas em função da exposição à luz ultravioleta. Os resultados obtidos revelaram a formação de intermediários oxidados, com grupamentos C=O. A combinação de dados da fotodegradação de HPA com seu estudo via eletroquímica - utilizando técnicas espectroscópicas para a identificação e caracterização de produtos - trouxe correlações importantes para esclarecer as transformações envolvidas nas etapas iniciais da fotodegradação dessas substâncias. A comparação das estruturas dos intermediários de fotodegradação e dos produtos de oxidação eletroquímica de HPA mostra que o início do processo fotocatalítico de HPA envolve uma etapa de oxidação de maneira análoga ao processo eletroquímico. / One class of chemicals that is present in the particulate matter in the atmosphere is of the so-called polycyclic aromatic hydrocarbons (PAH). They are object of special interest and concern due to their mutagenic properties and carcinogenic effects. PAH are characterized by the presence of two or more aromatic rings in their structure, and they are produced by the burning of organic fuels in a limited amount of oxygen. The study of the photochemical behavior of PAHs is relevant for clarifying some aspects of these complex systems. In this work, we perform experiments that include the UV irradiation of PAH, to observe which species are produced in such condition. Such investigations include the use of a photocatalysts, titanium dioxide – TiO2 – and that will allow the comparison between degradation products in the absence and in the presence of catalysts. Spectroscopic techniques were employed to monitorate the intermediates formed in the photoinduced degradation of PAH and their nitro derivates adsorbed or not on the photocatalyst TiO2. To perform the study of the photochemical reactions, the several PAH and nitro PAH were pre-adsorbed on TiO2 or SiO2, and then irradiated in 254 nm, in pre-determined time intervals. Changes in the structure of the molecules were observed after the exposure to the ultraviolet radiation. Results thus obtained revealed the production of oxidized intermediates bearing the C=O group. The joint analysis of the photodegradation data with those produced by electrochemical means - using spectroscopic techniques to the identification and characterization of the products - lead to important correlations that helped to clarify the transformations that take place in the initial steps of the photodegradation of PAH. By comparing the structures of the intermediates formed both in the photodegradation processes and in the electrochemical oxidation of PAH, it was possible to conclude that the first part of the photocatalytical degradation of those PAH include an oxidation step that is analogous to the electrochemical process.

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