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Mikrotalasno stimulisane transformacije prirodnih i sintetičkih karboksilnih kiselina i njihovih derivata / Microwave-assisted transformation of natural and synthetic carboxylic acids and their derivativesPavlović Ksenija 25 September 2014 (has links)
<p>Predviđena istraživanja u ovoj doktorskoj disertaciji su usmerena u pravcu <br />modifikacije klasičnih metoda i postupaka za transformaciju karboksilne grupe <br />prirodnih i sintetičkih karboksilnih kiselina. Modifikacije su rađene novim, <br />savremenim, ekonomski i ekološki opravdanim metodama rada u <br />mikrotalasnom reaktoru. Modifikovanim sintetskim postupcima u <br />mikrotalasnom reaktoru urađena je sinteza amida, hidroksamskih derivata, <br />kao i redukcija individualnih naftnih kiselina i smeše prirodnih naftnih kiselina <br />„Velebit“ do alkohola. Prirodne naftne kiseline korišćene u ovom radu su prvo <br />izolovane iz gasne frakcije (interval destilacije 168-290 °C) vojvođanske nafte <br />„Velebit“ a potom prečišćene i razdvojene na uže frakcije na osnovu različite <br />kiselosti. Nakon toga, izvršena je njihova karakterizacija GC-MS-EI analizom <br />(čime je potvrđeno da dolazi do strukturne diferencijacije kiselina). U radu je <br />takođe ispitana biološka aktivnost sintetizovanih derivata. Proučavan je uticaj <br />prirodnih naftnih kiselina „Velebit“ i njenih derivata na rast pet sojeva <br />Pseudomonas sp., kao i uticaj odabranih sintetisanih jedinjenja na proliferaciju <br />četiri ćelijske linije humanih tumora pri čemu je kao kontrola služila jedna <br />zdrava humana ćelijska linija.</p> / <p>The investigation of this doctoral dissertation is directed toward the modification of the transformation of the carboxylic group of natural and synthetic carboxylic acids. The dissertation takes into consideration the classical methods and procedures of the reaction and modifies them using microwave reactor. The synthesis of amides, hydroxamic derivatives, as well as the reduction of individual petroleum acids and acid mixtures of natural oil "Velebit" to alcohol were achieved by the modifications made to the synthetic methods in the microwave reactor. The natural oil acids used within this study were first isolated from the gas fraction (distillation interval 168-290 °C) of the Vojvodina's crude oil "Velebit", and then purified and separated by the narrow fractions under the different acidity. After that, their characterisation was made by the GC-MS-EI analysis which confirmed that the structural differentiation of acids had been achieved. Also, the biological activity of the synthesized derivatives are analysed. The impact of natural petroleum acids "Velebit" and its derivatives on the growth of five strains of Pseudomonas sp. was studied, as well as the impact of selected synthesized compounds on the proliferation of four human tumor cell lines wherein one healthy human cell lines used as the control.</p>
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S?ntese de catalisadores nanoporosos na aus?ncia total e parcial de direcionadores org?nicos para pir?lise catal?tica de ?leos pesados e intermedi?riosCosta, Maria Jos? Fonseca 03 June 2013 (has links)
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Previous issue date: 2013-06-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The processing of heavy oil produced in Brazil is an emergency action and a strategic
plan to obtain self-sufficiency and economic surpluses. Seen in these terms, it is indispensable
to invest in research to obtain new catalysts for obtaining light fraction of hydrocarbons from
heavy fractions of petroleum. This dissertation for the degree of Doctor of Philosophy reports
the materials preparation that combine the high catalytic activity of zeolites with the greater
accessibility of the mesoporosity, more particularly the HZSM-5/MCM-41 hybrid, done by
synthesis processes with less environmental impact than conventional ones. Innovative
methodologies were developed for the synthesis of micro-mesoporous hybrid material by dual
templating mechanism and from crystalline zeolitic aluminosilicate in the absence of organic
template. The synthesis of hybrid with pore bimodal distribution took place from one-single
organic directing agent aimed to eliminate the use of organic templates, acids of any kind or
organic solvents like templating agent of crystalline zeolitic aluminosilicate together with
temperature-programmed microwave-assisted, making the experimental procedures of
preparation most practical and easy, with good reproducibility and low cost. The study about
crystalline zeolitic aluminosilicate in the absence of organic template, especially MFI type, is
based on use of H2O and Na+ cation playing a structural directing role in place of an organic
template. Advanced characterization techniques such as X-Ray Diffraction (XRD), Fourier
Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Highresolution
Transmission Electron Microscopy (HRTEM), Adsorption of N2 and CO2, kinetic
studies by Thermogravimetric Analysis (TGA) and Pyrolysis coupled to Gas
Chromatography/Mass Spectrometry (Pyrolysis-GC/MS) were employed in order to evaluate
the synthesized materials. Achieve the proposed objectives, has made available a set of new
methodologies for the synthesis of zeolite and hybrid micro-mesoporous material, these
suitable for catalytic pyrolysis of heavy oils aimed at producing light fraction / O processamento do petr?leo pesado produzido no Pa?s ? uma a??o emergencial e
estrat?gica para obter a auto-sufici?ncia e super?vits econ?micos. Neste sentido, ?
indispens?vel o investimento em pesquisas de novos catalisadores para obten??o de derivados
leves a partir de fra??es pesadas do petr?leo. O trabalho de doutorado aqui reportado dedicouse
? prepara??o de materiais que combinem, numa ?nica estrutura, a elevada atividade
catal?tica de ze?litas, com melhor acessibilidade de materiais mesoporosos, como a estrutura
h?brida HZSM-5/MCM-41, utilizando processos de s?ntese com menor impacto ambiental que
os convencionais. Metodologias inovadoras foram desenvolvidas para a s?ntese do catalisador
h?brido micro-mesoporoso ou ze?lito-mesoporoso por mecanismo de direcionamento
estrutural via duplo agente diretor org?nico e tamb?m a partir de estrutura zeol?tica sintetizada
na aus?ncia total de direcionador org?nico. Esse ?ltimo, tamb?m chamado de s?ntese do
h?brido com distribui??o bimodal de poros a partir de um ?nico agente diretor org?nico, visou
eliminar o uso dos direcionadores org?nicos, ?cidos de qualquer natureza ou solventes
org?nicos como molde estrutural da estrutura zeol?tica em conjunto com o m?todo
hidrot?rmico assistido por irradia??o via micro-ondas, tornando o procedimento experimental
de prepara??o pr?tico e simples, com boa reprodutibilidade e menor custo. A metodologia de
prepara??o da ze?lita MFI do tipo ZSM-5 utiliza H2O e c?tions Na+ no papel de
direcionamento estrutural e compensa??o de cargas na estrutura. T?cnicas relevantes de
caracteriza??o, como Difra??o de Raios-X (XRD), Espectroscopia no Infravermelho com
Transformada de Fourier (FTIR), Microscopia Eletr?nica de Varredura (SEM), Microscopia
Eletr?nica de Transmiss?o de Alta Resolu??o (HRTEM), Adsor??o de N2 e CO2, estudos
cin?ticos via An?lises Termogravim?tricas (TGA) e Pir?lise acoplada ? Cromatografia
Gasosa/Espectrometria de Massas (Pyrolysis-GC/MS), foram empregadas no intuito de
avaliar os materiais sintetizados. Alcan?ados os objetivos propostos, disponibilizou-se um
conjunto de novas metodologias para s?ntese de catalisadores zeol?ticos e h?bridos micromesoporosos,
estes adequados para pir?lise catal?tica de ?leos pesados visando ? produ??o de
derivados leves
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Sinteza i biološka aktivnost novih steroidnih heterocikličnih jedinjenja / Synthesis and biological activity of new steroidal heterocyclic compoundsOklješa Aleksandar 24 July 2015 (has links)
<p>U ovoj doktorskoj disertaciji ispitane su 1,3-dipolarne<br />cikloadicione reakcije steroidnih azido-nitrila, nitrona i<br />nitril-oksida, pri čemu su sintetizovana različita<br />heterociklična steroidna jedinjenja androstanske i estranske<br />serije. Utvrdjene su strukture novosintetizovanih<br />jedinjenja. Ispitana je biološka aktivnost odabranih<br />jedinjenja.</p> / <p>In this PhD thesis 1,3-dipolar cycloadditions of<br />steroidal azido-nitriles, nitrones and nitrile-oxide were<br />examined. Various steroidal heterocyclic compounds in<br />the androstane and estrane series were synthesised. The<br />structural characterisation of newly synthesised<br />compounds was done. Biological activity of selected<br />compounds was examined.</p>
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