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Orientadores: Eduardo Augusto Caldas Batista, Antonio José de Almeida Meirelles / Dissertação (mestrado) - Universidade Estadual de Campinas, Fauldade de Engenharia de Alimentos / Made available in DSpace on 2018-08-17T21:09:08Z (GMT). No. of bitstreams: 1 Fonseca_LucianaAparecidaAndradePreviato_M.pdf: 1748931 bytes, checksum: 613a144c2469dfa664248bafa33dc2ac (MD5) Previous issue date: 2011 / Resumo: Dados de equilíbrio são úteis para o projeto e otimização de processos que envolvem separação de fases, como destilação e extração. Os álcoois superiores são subprodutos do processo de destilação relacionados com o aroma de bebidas alcoólicas e que, quando purificados podem agir como solvente. Esse estudo tem por objetivo a obtenção de dados isobáricos de Equilíbrio Líquido-Vapor (ELV) para sistemas binários e ternários envolvendo álcoois superiores. Dados de Equilíbrio Líquido-Vapor foram medidos para os sistemas binários compostos por 2-propanol/2-metil-1-butanol a 560 e 760 mmHg e para os sistemas ternários compostos por 2-propanol/1-butanol/3-metil-1-butanol e 2-propanol/2-metil-1-propanol/2-metil-1butanol, ambos a 760 mmHg. As medidas experimentais foram realizadas em ebuliômetro Fischer (VLE 602) e as composições das fases foram determinadas por cromatografia gasosa. A consistência termodinâmica dos dados de ELV binário P-T-x-y foi avaliada pelo teste de área e teste de van Ness-Fredenslund e os resultados comprovaram a boa qualidade dos dados de ELV determinados nesse trabalho. Os parâmetros de interação binária dos modelos NRTL, Wilson e UNIQUAC foram ajustados aos dados experimentais dos sistemas binários utilizando-se o software comercial Aspen Plus 12.1. Os resultados mostram uma boa descrição do ELV por esses modelos. Esses parâmetros foram ainda utilizados para descrever ELV dos sistemas ternários. Esses últimos resultados mostram uma boa concordância entre os dados experimentais e os calculados / Abstract: Equilibrium data are useful for design and optimization of processes involving phase separation, such as distillation and extraction. The higher alcohols are byproducts of the distillation process related to the flavor of alcoholic beverages and that when purified can act as a solvent. This study aims to obtain isobaric Vapor-Liquid Equilibrium (VLE) data for binary and ternary systems involving higher alcohols. Vapor Liquid Equilibrium were measured for the binary system composed by 2-propanol/2-methyl-1-butanol at 560 and 760 mmHg and for the ternary systems composed by 2-propanol/1-butanol/3-methyl-1-butanol and 2-propanol/2-methyl-1-propanol/2-methyl-1butanol, both at 760 mmHg. The experimental measurements were performed in a Fischer ebulliometer (VLE 602) and the phase compositions were determined by gas chromatography. Thermodynamic consistency of the VLE binary data P-T-x-y was evaluate by area test and van Ness-Fredenslund test and the results proved the good quality of the VLE data determined in this work. The binary interaction parameters of the NRTL, Wilson and UNIQUAC models were fitted to the experimental binary VLE data in the commercial software Aspen Plus 12.1. The results show a good description of the VLE data. These parameters were used to describe the VLE data for the ternary systems and the results show a good agreement between experimental and calculated data / Mestrado / Engenharia de Alimentos / Mestre em Engenharia de Alimentos

A novel small molecule, 1-ethoxy-3-(3,4-methylenedioxyphenyl)-2-propanol (EOD), was synthesized in our laboratory. Previously, we reported pharmacological properties of EOD, triggering apoptosis in Human umbilical vein endothelial cells (HUVECs). Here, we further investigated the effects of EOD on the growth of A549 human lung cancer cells. EOD treatment induced apoptosis in A549 cells via up-regulating the expression of P53 protein, blocking cell cycle partly at G1 phase, and ultimately activating caspase-3. In contrast, caspase-8 might be irrelevant to EOD-triggered apoptosis. This study indicated that EOD might be a potential chemopreventive agent for lung cancer. The work would encourage us to add more novel compounds to our 'library' of small molecules derived through modern synthetic organic chemistry, and would drive us to determine the proteins that the compounds target.

Ces derniers temps, des procédés commerciaux basés sur la technologie photocatalytique, sont arrivés sur le marché, afin de satisfaire la demande croissante du traitement de l’air intérieur. L’objectif de ce présent travail est de développer une nouvelle méthodologie pour évaluer l’efficacité de ce nouveau procédé. Pour l’étude de l’application de la photocatalyse au traitement de l’air intérieur, un dispositif expérimental a été mis au point et deux méthodes analytiques ont été développées (ATD-GCMS et GC-PDHID). La performance de la dégradation photocatalytique du 2-propanol et du toluène à faibles concentrations (ppbv) a été étudiée. L’influence des différents paramètres (humidité relative, débit, concentration initiale, etc.) et leurs interactions sur la conversion, la formation des intermédiaires et la minéralisation au CO2 a été établie / Many commercial systems based in the photocatalytic technology have reached the market recently in order to address the growing demand for improve poor indoor air qualities. The present work deals with the development of a new methodology in order to evaluate the efficiency of this process. For the study of photocatalytic oxidation for indoor air applications, an experimental set-up was designed and two analytical tools (ATD-GC-MS and GC-PDHID) were developed. The performance of the photocatalytic treatment of 2-propanol and toluene at indoor air concentrations levels (ppbv) were realised. The influence of several parameters and their interactions effects on the conversion, by-product formation and mineralization to CO2 were established

A new free radical chain process for the allylation of hydrocarbons and some other substrates utilizing substituted allyl bromides (R-H + C=C-C-Br -> R-C-C=C + HBr) has been developed. Good to excellent yields were observed in all cases. Kinetic chain measurements and competition experiments were performed in order to elucidate the mechanism of the reaction. Overall, the results are consistent with a free radical chain process with bromine atom as the chain carrier. Substitution effects on the reactivity of the allyl bromides (CH2=C(Z)CH2Br) and their influence on the overall reaction rate were studied by conducting several competition experiments. The relative rate constants for addition of benzyl radical to CH2=C(Z)CH2Br are: Z=CN(180), COOEt(110), Ph(65), H(1.0). The trend of electronegativity/reactivity of these reactions was very similar to that reported for addition of benzyl radical to substituted alkenes. Other than alkyl aromatics (PhCH3, PhCH(CH3)2), other substrates (i.e., 2- propanol, phenyl cyclopropane) were also tested for this allylation reaction. The magnitude and scope of these reactions, and their synthetic utility is discussed. / Ph. D.

Hydrogen processing is becoming increasingly important not only in the production of electricity but also during its accumulation. One of the energy storage options are liquid organic hydrogen carriers (LOHC). The main drawback of LOHC is the need for a large amount of thermal energy to release molecular hydrogen. We can bypass this issue using heterogeneous catalysis by transferring hydrogen from LOHC to acetone and using the produced 2-propanol (IPA) in the fuel cell. This innovative strategy of getting electri- cal energy from LOHC can be potentially energetically neutral. In this work, we studied highly ordered Co3O4(111) model catalysts for IPA oxidation in the as-prepared state and enhanced with platinum (Pt) nanoparticles. Catalysts were prepared by Physical Vapour Deposition (PVD) and further investigated by means of Low Energy Electron Diffrac- tion (LEED), X-ray Photoelectron Spectroscopy (XPS), Scanning Tunneling Microscopy (STM) and Temperature Programmed Desorption (TPD). The nucleation process of Pt on the as-prepared Co3O4(111) surface was studied by depositing low amounts 0.04 and 0.13 monolayer (ML) of Pt, that create clusters as small as 2 or 3 atoms with no need for a special nucleation site. We have identified the formation of Pt-induced defects in the atomically flat cobalt oxide...

Hydrogen processing is becoming increasingly important not only in the production of electricity but also during its accumulation. One of the energy storage options are liquid organic hydrogen carriers (LOHC). The main drawback of LOHC is the need for a large amount of thermal energy to release molecular hydrogen. We can bypass this issue using heterogeneous catalysis by transferring hydrogen from LOHC to acetone and using the produced 2-propanol (IPA) in the fuel cell. This innovative strategy of getting electri- cal energy from LOHC can be potentially energetically neutral. In this work, we studied highly ordered Co3O4(111) model catalysts for IPA oxidation in the as-prepared state and enhanced with platinum (Pt) nanoparticles. Catalysts were prepared by Physical Vapour Deposition (PVD) and further investigated by means of Low Energy Electron Diffrac- tion (LEED), X-ray Photoelectron Spectroscopy (XPS), Scanning Tunneling Microscopy (STM) and Temperature Programmed Desorption (TPD). The nucleation process of Pt on the as-prepared Co3O4(111) surface was studied by depositing low amounts 0.04 and 0.13 monolayer (ML) of Pt, that create clusters as small as 2 or 3 atoms with no need for a special nucleation site. We have identified the formation of Pt-induced defects in the atomically flat cobalt oxide...

In this thesis, carbon supported platinum nanoparticles have been prepared by using PtCl4 as a starting material and 1-octanethiol, 1-decanethiol, 1-dodecanethiol and 1-hexadecanethiol as surfactants for methanol, ethanol and 2-propanol oxidation reactions. The structure, particle sizes and surface morphologies of the platinum were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM) and transmission electron microscopy (TEM). XRD and TEM results indicate that all prepared catalysts have a face centered cubic structure and are homogeneously dispersed on the carbon support with a narrow size distribution (2.0 to 1.3 nm). X-ray photoelectron spectra of the catalysts were examined and it was found that platinum has two different oxidation state, Pt (0) and Pt (IV), oxygen and sulfur compounds are H2Oads and OHads, bounded and unbounded thiols. The electrochemical and electrocatalytic properties of those catalysts were investigated towards C1 to C3 alcohol oxidations by cyclic voltammetry (CV) and chronoamperometry (CA). The highest electrocatalytic activity was obtained from catalyst I which was prepared with 1-octanethiol. This may be attributed to decrease in the ratio of bounded to unbounded thiol species and increase in Pt (0)/Pt (IV), H2Oads/OHads ratios, electrochemical surface area, CO tolerance and percent platinum utility.

Topical exposure to isopropyl alcohol has been reported in the literature to be toxic if sufficient isopropyl alcohol is absorbed (1-5). A clinical case is reported where a 48-y-old female presented with multiple unexplained cardiac and neurological deficits. The woman had developed the deficits over a 6-mo period in which she had been soaking towels with isopropyl alcohol and applying then to her skin overnight to ease arm pain she was experiencing. Cessation of the isopropyl alcohol exposure resolved her deficits within 3 d. A controlled repeat dermal exposure to isopropyl alcohol under clinical observation reproduced the deficits noted with corresponding serum and urine concentrations of isopropyl alcohol and acetone. Cessation of topical isopropyl alcohol exposure lead to subsequent resolution of all toxicities.

In biosensors, printing involves the transfer of materials, proteins or cells to a substrate. It offers many capabilities thatcan be utilized in many applications, including rapid deposition and patterning of proteins or other biomolecules.However, issues such as stability when using biomaterials are very common. Using proteins, enzymes, as biomaterialink require immobilizations and modifications due to changing in the structural conformation of the enzymes, whichleads to changes in the properties of the enzyme such as enzymatic activity, during the printing procedures andrequirements such as solvent solutions. In this project, an innovative approach for the fabrication of proteinmicroparticles based on cross-linking interchange reaction is presented to increase the stability in different solvents.The idea is to decrease the contact area between the enzymes and the surrounding environment and also preventconformation changes by using protein microparticles as an immobilization technique for the enzymes. The theory isbased on using a cross-linking reagent trigging the formation of intermolecular bonds between adjacent proteinmolecules leading to assembly of protein molecules within a CaCO3 template into a microparticle structure. TheCaCO3 template is removed by changing the solution pH to 5.0, leaving behind pure highly homogenous proteinmicroparticles with a size of 2.4 ± 0.2 μm, according to SEM images, regardless of the incubation solvents. Theenzyme model used is Horse Radish Peroxidase (HRP) with Bovine Serum Albumin (BSA) and Glutaraldehyde (GL)as a cross-linking reagent. Furthermore, a comparison between the enzymatic activity of the free HRP and the BSAHRPprotein microparticles in buffer and different solvents are obtained using Michaelis-Menten Kinetics bymeasuring the absorption of the blue product produced by the enzyme-substrate interaction using a multichannelspectrophotometer with a wavelength of 355 nm. 3,3’,5,5’-tetramethylbenzidine (TMB) was used as substrate. As aresult, the free HRP show an enzymatic activity variation up to ± 50 % after the incubation in the different solventswhile the protein microparticles show much less variation which indicate a stability improvement. Moreover, printingthe microparticles require high microparticle concentration due to contact area decreasing. However, usingmicroparticles as a bioink material prevent leakage/diffusion problem that occurs when using free protein instead.