Orientadores: Ronei Jesus Poppi, Adriana Vitorino Rossi / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-07-27T03:32:16Z (GMT). No. of bitstreams: 1 DuenasCueva_JacquelineM_M.pdf: 3974070 bytes, checksum: 64ab509cd173dd2658191f6368a5d176 (MD5) Previous issue date: 2000 / Mestrado

The diploma thesis compares the photophysical, photooxidative and photocytotoxic properties of four polymer nanofabrics with encapsulated 5,10,15,20 - meso - tetraphenylporphyrin (TPP). The main focus of the work lies especially in the study of the effect of polymer oxygen permeability on the ability of nanofabrics to produce singlet oxygen and the utilization of nanofabrics for measurement of the polymer oxygen permeability and polymer oxygen diffusion coefficients. A possible application of nanofabrics in the framework of oxygen detection, photooxidation of substrates and photodesinfection has been studied as well.

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Thesis advisor: Marc L. Snapper / Chapter 1 Review of methodology developments in the area of selective tosylation of alcohols. Chapter 2 Development of a catalytic enantioselective tosylation of alcohols with an amino-acid-based organocatalyst. / Thesis (MS) — Boston College, 2011. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Electrohydrodynamic (EHD) phenomena involve the interaction between electrical and flow fields in a dielectric fluid medium. In EHD conduction, the electric field causes an imbalance in the dissociation-recombination reaction of neutral electrolytic species, generating free space charges which are redistributed to the vicinity of the electrodes. Proper asymmetric design of the electrodes generates net axial flow motion, pumping the fluid. EHD conduction pumps can be used as the sole driving mechanism for small-scale heat transport systems because they have a simple electrode design, which allows them to be fabricated in exceedingly compact form (down to micro-scale). EHD conduction is also an effective technique to pump a thin liquid film. However, before specific applications in terrestrial and micro-gravity thermal management can be developed, a better understanding of the interaction between electrical and flow fields with and without phase-change and in the presence and absence of gravity is needed. With the above motivation in mind, detailed experimental work in EHD conduction-driven single- and two-phase flow is carried out. Two major experiments are conducted both terrestrially and on board a variable gravity parabolic flight. Fundamental behavior and performance evaluation of these electrically driven heat transport systems in the respective environments are studied. The first major experiment involves a meso-scale, single-phase liquid EHD conduction pump which is used to drive a heat transport system in the presence and absence of gravity. The terrestrial results include fundamental observations of the interaction between two-phase flow pressure drop and EHD pump net pressure generation in meso-scale and short-term/long-term, single- and two-phase flow performance evaluation. The parabolic flight results show operation of a meso-scale EHD conduction-driven heat transport system for the first time in microgravity. The second major experiment involves liquid film flow boiling driven by EHD conduction in the presence and absence of gravity. The terrestrial experiments investigate electro-wetting of the boiling surface by EHD conduction pumping of liquid film, resulting in enhanced heat transfer. Further research to analyze the effects on the entire liquid film flow boiling regime is conducted through experiments involving nanofiber-enhanced heater surfaces and dielectrophoretic force. In the absence of gravity, the EHD-driven liquid film flow boiling process is studied for the first time and valuable new insights are gained. It is shown that the process can be sustained in micro-gravity by EHD conduction and this lays the foundation for future experimental research in electrically driven liquid film flow boiling. The understanding gained from these experiments also provides the framework for unique and novel heat transport systems for a wide range of applications in different scales in terrestrial and microgravity conditions.

Zugl.: Karlsruhe, Universiẗat, Diss., 2007.

Universiẗat, Diss., 2000--München.

A sÃntese de porfirinas e metaloporfirinas vÃm se tornando cada vez mais crescente devido as suas aplicaÃÃes em processos tecnolÃgicos e medicinais, os quais envolvem modificaÃÃes quÃmicas atravÃs da introduÃÃo de diferentes substituintes e Ãons metÃlicos no anel macrociclo. Essas modificaÃÃes provocam mudanÃas nas propriedades espectroscÃpicas destes compostos decorrentes da perturbaÃÃo do sistema π conjugado. Assim, o presente trabalho envolve a sÃntese, caracterizaÃÃo e a investigaÃÃo das propriedades espectroscÃpicas de duas meso porfirinas com cadeias laterais diferenciadas, a 5,10,15,20-tetra-[4-(2-(3-n-pentadecilfenoxi)etoxi]fenilporfirina e a 5,10,15,20-tetra-4-[3-(3-n-pentadecilfenoxi)propoxi]fenilporfirina, ambas derivadas do cardanol, um dos constituintes do LÃquido da Casca da Castanha de Caju (LCC), alÃm da obtenÃÃo do complexo metalado com o Ãon tÃrbio [Tb(3-n-PDPP)(acac)]. O espectro de absorÃÃo UV-Vis das meso porfirinas, apresentou um conjunto de bandas as quais sÃo compatÃveis com as meso estruturas: uma banda Soret λ= 422 e 424 nm e quatro bandas Q entre 500 e 649 nm. O espectro de fluorescÃncia das meso porfirinas apresentou uma banda de emissÃo intensa em λ= 654-658 nm e outra de pouca intensidade em λ=713-716 nm. O espectro de excitaÃÃo apresentou o mesmo perfil do espectro de absorÃÃo, revelando que a emissÃo advÃm das absorÃÃes das bandas Soret e Q, gerando a transiÃÃo radiativa fluorescente. Quanto à forma metalada [Tb(3-n-PDPP)(acac)], fatores como a escolha do sal de tÃrbio, o solvente e a estequiometria da reaÃÃo foram determinantes para sua obtenÃÃo. As anÃlises de caracterizaÃÃo para o complexo obtiveram os seguintes resultados: reduÃÃo do nÃmero de bandas Q; ausÃncia do sinal referente aos hidrogÃnios centrais da porfirina no espectro de RMN de 1H (-2,4 ppm); presenÃa de uma banda caracterÃstica de deformaÃÃo axial do grupamento C=O referente ao ligante axial acetilacetonato; presenÃa de trÃs bandas em λ= 597 nm, λ= 654 nm e λ= 718 nm no espectro de emissÃo de fluorescÃncia. TambÃm foi determinado o rendimento quÃntico das duas porfirinas base livre e dos complexos com os Ãons metÃlicos zinco e tÃrbio, com o intuito de verificar a influÃncia do Ãon metÃlico e dos substituintes laterais nas propriedades espectroscÃpicas destes compostos. / The synthesis of porphyrins and metalloporphyrins have become growing consistently due to their applications in technological and medical processes, which involve chemical modifications by introducing different substituents and metal ions in the macrocycle ring. These modifications cause changes in the spectroscopic properties of these compounds resulting from the disturbance of the π conjugated system. Therefore, this work involves the synthesis, characterization and investigation of the spectroscopic properties of two meso porphyrins with different side chains, the 5,10,15,20-tetra[4-(2-(3-n-pentadecilfenoxi) ethoxy] phenilporphyrin and 5,10,15,20-tetrahydro-4-[3-(3-n-pentadecilfenoxi)propoxy] phenilporphyrin, both derived from cardanol, one of the components of the cashew nut shell liquid (CNSL), further obtaining the metalated complex with the Terbium ion [Tb (3-n-PDPP)(acac)]. The absorption spectrum of the UV-Vis meso porphyrins, presented a set of bands which are consistent with the meso structures: a Soret band λ = 422 and 424 nm and four Q bands between 500 and 649 nm. The fluorescence spectrum from porphyrins meso showed an intense emission band λ = 654-658 nm and another low intensity at λ = 713-716 nm. The excitation spectrum showed the same absorption spectrum profile, showing that the emission arises from absorption of the Soret and Q bands, generating fluorescent radiative transition. As for the metalated form [Tb (3-n-PDPP) (acac)], factors like the choice of Terbium salt, solvent and reaction stoichiometry were determinant to obtain it. The characterization analysis of the complex gave the following results: reduction the number of Q bands; absence of the signal relating to the central porphyrin hydrogens in the 1H NMR spectrum (-2,4 ppm); presence of a band characteristic of the axial deformation of the C=O group regarding the axial ligand acetylacetonate; the presence of three bands at λ = 597 nm, λ = 654 nm and λ = 718 nm on the fluorescence emission spectrum. It was also determined the quantum yield of the two porphyrin free base and complexes with the metal ions zinc and terbium, in order to verify the influence of metal ion and the side substituents on the spectroscopic properties of these compounds.

京都大学 / 0048 / 新制・論文博士 / 博士(理学) / 乙第12830号 / 論理博第1541号 / 新制||理||1578(附属図書館) / 31368 / (主査)教授 余田 成男, 教授 石川 裕彦, 教授 向川 均 / 学位規則第4条第2項該当 / Doctor of Science / Kyoto University / DGAM

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