Thesis (Ph. D.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 74-82). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users. Also available online.

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (doctoral)--Universität Hamburg, 1979.

Thesis (M.S.)--Villanova University, 2006. / Chemistry Dept. Includes bibliographical references.

Semiconducting polymers had been well studied and applied in many research areas. They are such as electroactive actuators, electrochromic materials, microwave-absorbent coatings, polymer solar cells, polymer light-emitting diodes, etc. Traditional semiconductors are metals/oxides and they are expensive, toxic and harmful to the environment. Compared to the traditional n-conjugated main-chain polymers, side-chain conductive polymers have a lower volume percentage of the charge transport moieties yet they possess advantages such as excellent mechanical strength, good rheological properties, solubility in common organic solvents and purer emission hue. Furthermore, the performances of the side-chain semiconducting polymers can be engineered easily by changing their composition or by choosing an appropriate additional polymerization method. As a result, several series of soluble, semiconducting and luminescent side-chain homopolymers and copolymers have been synthesized and characterized. In this thesis, several series of vinyl conductive polymers have been prepared using the facile solution free radical, anionic and atom transfer radical polymerization methods. The novel polymers including the homopolymer P(ADN), two highly soluble homopolymers P(2ADN) and P(3ADQ), two series of ADN moities containing copolymer P(ADN-co-S) and P(ADN-co-VK), a series of pyrene moieties containing copolymer P(PyPA-co-VPy) and two novel amphiphilic BAB-type block copolymers, ADN-PEG3400-ADN and Py-PEG3400-Py which contain blue and greenish-blue fluorescent moieties. The chemistry and physical properties of the intermediates, the resulting polymers were characterized using nuclear magnetic resonance spectroscopy (NMR), matrix-assisted laser desorption ionization time-of-flight mass spectrum (MALDI-TOF MS), fourier-transform infrared spectroscopy (FT-IR), elemental analysis (EA), gel permeation chromatography (GPC), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), UV-Visible spectroscopy (UV-Vis), photoluminescence spectroscopy (PL), cyclic voltammetry (CV), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and fabrication of polymer light-emitting diodes (PLED) and their measurements.

In this study, fluorescent polymers with pendant quinoline groups were synthesized by reversible addition-fragmentation chain transfer polymerization (RAFT) from a fluorescent quinoline-based vinyl monomer, synthesized in multiple steps from p-nitroaniline and crotonaldehyde. The structures of the synthesized vinyl monomer and polymers were confirmed by NMR and FT-IR spectroscopy, X-ray studies and modeling stdies. The photophysical properties of the synthesized quinoline compounds and resulting polymers were investigated. In order to evaluate the binding potential of our quinoline-based polymer in the presence of transition metal ions, preliminary studies on a complexation of quinoline-based polymers with Zn, Cd, Hg, Fe, and Ni were carried out. The investigation of fluorescence properties of the complexes showed fluorescence quenching for Fe(II), and fluorescence enhancement for the remaining ions [Zn(II), Cd(II), Hg(II), and Ni(II)].

Click chemistry is one of the growing areas of research which is applied in the design and synthesis of a wide range of polymeric architectures. This investigation focuses on the synthesis of fluorescent coumarin based polymers by “click” A-B step growth polymerization process and evaluation of their photophysical properties. Non-fluorescent azide-alkyne functionalized coumarin-based monomers were synthesized in multiple steps from 2,4-dihydroxybenzaldehyde in reasonable yields. Polymers with coumarin backbone were synthesized from azide-alkyne functionalized coumarin monomers via the Cu(I) catalyzed 1,3-dipolar cycloaddition reaction between azides and alkynes, a typical click reaction, to form polymers whose repeating units are connected by a 1,2,3-triazole ring. The structures of the synthesized polymers were confirmed by NMR and FT-IR spectroscopy. Finally, the photophysical properties of the synthesized monomers and polymers were evaluated in DMF. All coumarin based monomers showed reduced fluorescent properties due to the quenching effect from the azido group. Although all polymers absorbed at maximum wavelength of 340 nm, a characteristic for coumarin chromophore, the homo-polymers emitted at a shorter wavelength of 413 nm as compared to the co-polymers which emitted at 421 nm.

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Orientador: Yaro Burian Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-18T15:41:19Z (GMT). No. of bitstreams: 1 Siqueira_GabrieladePaiva_M.pdf: 1004897 bytes, checksum: 434e195d542578fc2f9b88f6143f079d (MD5) Previous issue date: 2011 / Resumo: Este trabalho apresenta o estudo do comportamento elétrico de lâmpadas fluorescentes compactas. Ele engloba a análise dos componentes da lâmpada e do circuito do reator, a análise da estabilidade do ponto de funcionamento dessas lâmpadas, o estudo das características estáticas e dinâmicas, criação de modelo matemático, simulações e experimentos. Também é analisado o fenômeno de cintilações em lâmpadas fluorescentes desligadas. Inicialmente foi feita a análise geral das características da lâmpada e dos reatores magnéticos e eletrônicos. Foi feita uma análise comparativa entre os reatores eletrônicos e magnéticos levando-se em consideração as principais características de uso: tamanho, custo, efeito estroboscópico e fator de potência. Em seguida foi estudando o comportamento estático da lâmpada fluorescente. Foi feita a análise da estabilidade do ponto de funcionamento da lâmpada em regime estático levando-se em consideração o circuito externo e a dinâmica do plasma. Verificamos que existe uma boa aproximação para a curva característica estática na região de interesse. Ainda em regime estático observamos que, com corrente constante, existe uma oscilação periódica não senoidal na tensão, sobrepostas à tensão constante, da ordem de até uma dezena de volts e com freqüências da ordem de 10 kHz. O comportamento dinâmico da lâmpada fluorescente foi estudado a partir das equações do circuito externo, da dinâmica da lâmpada e da aproximação da característica estática. Simulações na freqüência de distribuição de energia elétrica (60 Hz) foram comparadas com os resultados obtidos experimentalmente. Simulando também o funcionamento da lâmpada alimentada por tensões senoidais em freqüências mais elevadas verificamos que a tensão e a corrente na lâmpada tendem para curvas senoidais em fase, confirmando que ela tende a funcionar como resistor em altas freqüências. As experiências em alta freqüência confirmaram essa tendência. Também notamos, através da verificação dos circuitos dos reatores de diversas lâmpadas ao longo dos anos, que o filtro de entrada dos reatores eletrônicos das lâmpadas fluorescentes compactas comerciais foi suprimido. Fato que se revelou causador de um evento indesejável dessas lâmpadas: a ocorrência de emissão de lampejos de luz de baixa intensidade e curta duração em intervalos da ordem de 1 minuto por algumas lâmpadas fluorescentes compactas desligadas. Foi analisado o motivo e proposta uma solução para eliminar este fenômeno / Abstract: This work presents a broad study of the electrical behavior of compact fluorescent lamps. It includes an analysis of the lamp components and the circuit of the reactor; an analysis of the stability on the operating point of the lamp; a study of static and dynamic characteristics; a development of a mathematical model; simulations and experiments. It is also analyzed the phenomenon of sparkling in turned off fluorescent lamps. First it was made a general analysis of the characteristics of those lamps with magnetic and electronic reactors. Then it was made a comparative analysis between them considering the main usage characteristics: size, cost, stroboscopic effect and power factor. It was then studied the static behavior of fluorescent lamps. It was made an analysis of the stability on the operation point of the lamp in static regime considering not only the external circuit but also the plasma dynamic. It was shown that there is a good approximation for the static characteristic curve in the region of interest. We also observed that, with a constant current, the voltage has a periodic (but not sinusoidal) oscillation on top of a constant value of voltage. This oscillation of dozens of volts has a frequency of about 10kHz. The dynamic behavior of the fluorescent lamp was studied by using: the equation of the external circuit, the equation of the lamp dynamic and the equation of the approximation of the static characteristic. It was made simulations in the frequency of electric energy distribution (60Hz) and they were compared with the results obtained experimentally. When it was simulated the functioning of the lamp fed by sinusoidal voltage in high frequencies, we saw that both voltage and current in the lamp tend towards sinusoidal curves in phase, confirming that the lamp has a tendency to function as a resistor in high frequencies. The experiences in high frequencies confirmed this trend. We also saw, by looking at reactors circuits over the years, that the entrance filter was suppressed from electronic reactors of commercial compact fluorescent lamps. This fact revealed to be the cause of an undesirable effect of these lamps: the emission of flashes with small intensity and short duration in intervals of about a minute by some fluorescent lamps when they are turned off. It was analyzed the reason and it was proposed a solution to eliminate this phenomenon / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica

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