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1
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LUCAS PENHA DUTRA
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synthesis and characterization of pyrazole-thiadiazole hybrid systems with potential trypanocidal activity
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Leader : MAURICIO SILVA DOS SANTOS
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MEMBRES DE LA BANQUE :
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CELSO DE OLIVEIRA REZENDE JÚNIOR
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MAURICIO FROTA SARAIVA
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MAURICIO SILVA DOS SANTOS
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Data: 25 févr. 2022
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Afficher le Résumé
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Chagas Disease (CD) was discovered in 1909 by Dr. Carlos Chagas and it is, until today, a public health problem. According to WHO, CD is one of the 20 Neglected Tropical Disease and affects the poorest people who live in Latin American, where the disease is endemic. It is caused by Trypanosoma cruzi, transmitted to humans by the triatomine bugs. The treatment of CD is based on two drugs, benznidazole and nifurtimox, both were developed more than 50 years ago. They have limited efficacy on chronic phase and cause many side effects. Thus, there is an urgent need to develop new compounds more active against T. cruzi, in both phases of the disease, and with less side effects. In this sense, heterocycles are an attractive class to design new drugs, because they are present in a plethora of bioactive compounds. Especially, azolic heterocycles 1H-pyrazole and 1,3,4-thiadiazole have gained considerable attention in the development of antiparasitic agents. Thus, in this work two new series of pyrazole-thiadiazole hybrids 1(a-l) and 2(a-l) have been planned with potential trypanocidal activity. The final products were synthesized using the key intermediates 3(a-l) and 4(a-l). Initially, two alternative methodologies to the final products synthesis were investigated. The carbonitriles 4(a,c,g,i,j) and the carboxamides 5(a,f,j) were used as raw materials in the first and second attempt, respectively. However, the desired products could not be obtained and the unexpected products 5(a,c,g,i,j) were formed in the first case and 6(a,f,j) in the second one. Finally, employing thiosemicarbazide and trifluoroacetic acid, the intermediates 3(a-l) and 4(a-l) were successfully converted into 1(a-l) and 2(a-l), respectively, in yields of 26 to 72% and 20 to 91%, in this order. All the compounds were characterized by FT-IR and the 6(a,f,j), 1(a-l) and 2(a-l) were also analyzed by HRMS, 1H and 13C NMR. So far, the majority of the tested derivatives, 1(a-k) e 2(a,b,d,f-l), did not exhibit toxicity against Vero cells, with CC50 >500 uM, except for 1(c,d), which presented a CC50 in 118,77 and 341,65 uM, respectively.
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2
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Tainara Aparecida Nunes Ribeiro
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SYNTHESIS OF IMIDAZO-PYRAZOLE-PYRIMIDINE DERIVATIVES FOR EVALUATION OF ANTIBACTERIAL ACTIVITY
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Leader : MAURICIO SILVA DOS SANTOS
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MEMBRES DE LA BANQUE :
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DANIEL HENRIQUES SOARES LEAL
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DANIELA SACHS
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FABIO AGUIAR ALVES
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MAURICIO SILVA DOS SANTOS
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Data: 3 mars 2022
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Diseases caused by bacteria have been a major problem worldwide since they are responsible for many deaths every year around the world and high health-related costs. In addition, the drug resistance has been raised significantly. Therefore, it is very relevant the research in order to developing new classes of antibacterial. There are many reports in the literature showing that heterocyclic compounds containing nitrogen atom have great biological potential, specially pyrazole moiety, which has showed remarkable antimicrobial activity. Thus, in this work aimed to synthesize new seven pyrazole derivatives 7-aryl-2,3,6,7-tetrahydro-5H-imidazo[1,2-c]pyrazolo[4,3-e]pyrimidine-5-thiones 1(a-g). The raw materials 5-amino-1-aryl-1H-pyrazole-4-carbonitriles 3(a-g) and the key intermediates 5-amino-1-aryl-4-(4,5-dihydro-1H-imidazole-2-yl)-1H-pyrazoles 2(a-g) were obtained in 47 to 71 % and 24 to 88% yields, respectively. The final products 1(a-g) were synthesized in 31 to 91% yields and completely characterized by Infrared Spectroscopy (FT-IR), High Resolution Mass Sprectrometry (HRMS) and Nuclear Magnetic Resonance (NMR). The compounds 1(a-g) are being evaluted against Escherichia coli through Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). These derivatives 1(a-g) did not show antibacterial activity against E. coli.
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3
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JULIANA CARONI SILVA GUIMARÃES
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ELABORATION AND CHARACTERIZATION OF A SOLID EXTRACTOR BASED ON EXPANDED POLYURETHANE SYNTHESISTED WITH GROSS GLYCEROL AS A POTENTIAL SYSTEM FOR REMOVAL OF ANIONIC DYE
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Leader : MERCES COELHO DA SILVA
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MEMBRES DE LA BANQUE :
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MARYS LENE BRAGA ALMEIDA
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DANIEL CRISTIAN FERREIRA SOARES
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MARCOS ROBERTO DE ABREU ALVES
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MERCES COELHO DA SILVA
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Data: 13 juil. 2022
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This work aimed to synthesize an expanded polyurethane (EPU) based on crude glycerol (CG), and another based on a mixture of vegetable oil (70%) and pure glycerin (PG) (30%), as an alternative to petroleum-derived polyol, and to evaluate its efficiency as an adsorbent of the anionic dye amaranth from aqueous solution. CG was obtained from a biodiesel plant and was characterized by Fourier Transform Infrared Spectrophotometer (FT-IV), determination of the hydroxyl number (IOH) and free glycerol content in the crude waste. The IOH and free glycerol values found for CG were, respectively, 505 mg KOH/g and 32.0±0.29%. EPUs were synthesized and characterized by apparent density, FT-IV, thermogravimetry (TGA) and zeta potential (pHpcz). The EPU synthesized with CG (EPU-CG) presented higher apparent density (130.80 Kg m-3) in relation to EPU synthesized with the mixture of vegetable oil and PG (EPU-Mist) (29.7 Kg m-3) , and proved to be less thermally stable. However, EPU-CG showed better performance in the adsorption tests, with more than 90% removal of amaranth (6 mg L-1) at pH 3 and room temperature, while EPU-Mist obtained 52.7% removal under the same conditions of study. The pHpcz values found were, respectively, 6.27 and 7.15 for EPU-Mist and EPU-CG. During the adsorption tests, the influence of pH, contact time and initial dye concentration were evaluated, and both EPUs obtained the best removal percentage at pH 2 and the lowest initial dye concentrations. The data obtained experimentally in the tests were adjusted to mathematical models of isotherm and adsorption kinetics. Both EPUs showed better fit to the Langmuir isotherm and to the pseudo-second order kinetics model. The maximum adsorption capacity (qmax) calculated for EPU-CG and EPU-Mist was 0.866 and 0.303 mg g-1, respectively. The reuse tests showed good performance for five consecutive cycles for EPU-CG and for three cycles for EPU-Mist. The results obtained suggest that glycerol is a raw material with great potential to replace petroleum-derived polyols in the synthesis of polyurethanes. However, its large-scale application still requires broader studies, in addition to the need for adjustments in the polyurethane formulation to increase the adsorption capacity.
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4
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GABRIEL DOS SANTOS E SILVA
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Synthesis, characterization, and evaluation of the cytotoxic activity of Geraniol analogues against the Glioblastoma tumor cell line U87MG
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Leader : MAURICIO FROTA SARAIVA
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MEMBRES DE LA BANQUE :
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MARCOS ROBERTO DE ABREU ALVES
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MAURICIO FROTA SARAIVA
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ÉRICO TOSONI COSTA
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Data: 20 juil. 2022
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Afficher le Résumé
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Cancer has long been a major public health problem and affects all countries around the world. By 2020, it is estimated that there will be approximately 19.3 million new cases and 10 million deaths from the disease. Cancer encompasses a wide variety of diseases, which differ in the regions of the body that are affected. One of the rarest and most lethal cancers is Glioblastoma multiforme (GBM), included in the class of central nervous system (CNS) cancers. Generally, patients with the disease live only 12 to 18 months after diagnosis. One problem with GBM is the lack of variety in the treatment of the disease: Only four drugs are approved by the FDA (Food and drug administration) and used in the treatment of the disease. Thus, the need arises for the development of new compounds that offer an effective and at the same time less aggressive treatment to healthy cells. In this context, products of natural origin have shown promise in fighting these cancerous cells. Among these products, some classes, such as terpenes, stand out. One of the most well-reported monoterpenes by the scientific community is Geraniol. Geraniol has shown interesting characteristics in the pharmacological field, especially when it comes to its anti-cancer activity. In this context, this research reports a proposal for the synthesis, characterization, and evaluation of the cytotoxic activity against glioblastoma tumor cells (U87MG strain) of 24 geraniol analogues, 16 of which are novel derivatives. The analogs consist of eight terpenic 1(a-h) amino alcohol derivatives and their four N,N-dialkenylated by-products (2a, 2c, 2e, and 2f), three acetylated 3a, 3b, and 3f derivatives, two mesylate intermediates 4a/4b, six derivatives from different nucleophiles 5(a-c) and 6(a-c) and two diamine derivatives 7a and 7b. The terpene amino alcohols 1a-h and their N,N-dialkenylated by-products 2a, 2c, 2e, and 2f were obtained with yields of 18-85%; the acetylated derivatives 3a, 3b, and 3f, 66-95%; the mesylate intermediates 4a and 4b, 90 and 96%, respectively; the derivatives 5b, 5c, and 5c(sub), 45-78%; the compounds 6a, 6b(sub) and 6c, 43-86% and the derivative 7a obtained with a yield of 81%. All products, except intermediates 4a and 4b (characterized by FT-IR only), were characterized by FT-IR and NMR (¹H, ¹³C, and DEPT-135). The novel derivatives were characterized by ESI-HRMS. The cytotoxic activity of 16 of the 24 analogues was evaluated against U87MG lineage cells, and IC50 values were calculated in comparison to Geraniol and the standard drug used in the treatment of GBM, Temozolomide (IC50 = 1mM or 1000 µM). The activity presented by the compound N,N-dialkenylated 2a with IC50 = 2.71 µM stands out, a value about 369 times higher than Temozolomide. Other derivatives (1e, 2e, 2f, 2c, 1a, and 7a) showed IC50 values ranging from 6.47 to 56.5 µM, also showing promise. The rest of the analogs evaluated presented IC50 >100 µM, the highest concentration value evaluated. Based on the results, it was possible to perform a structure-activity relation of the synthesized analogues.
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5
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PATRICIA MACIEL ALVES
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Synthesis, characterization and evaluation of the antimicrobial activity of new terpenoids derived from farnesol
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Leader : MAURICIO FROTA SARAIVA
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MEMBRES DE LA BANQUE :
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INÁCIO LUDUVICO
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DANIEL CRISTIAN FERREIRA SOARES
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DANIELA SACHS
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MARA RUBIA COSTA COURI
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MAURICIO FROTA SARAIVA
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Data: 21 juil. 2022
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Bacteria are capable of becoming resistant to some drugs. With the increasing use of antibacterials, often administered indiscriminately, an increase in the speed with which this resistance occurs and propagates has been observed. Bacterial resistance becomes a problem for global health due to clinical complications that these pathogens cause, such as infections without adequate treatment, and aggravating or prolonging diseases. In addition to making current treatments often obsolete and inefficient. In this scenario, the research and development of new antimicrobial agents become important. Within this context, the present work describes the synthesis, characterization, and antibacterial evaluation of sixteen farnesol derivatives, eight of which are farnesylaminoalcohols (2a-h), two mesylate intermediates (3a and 3b), two azide derivatives (4a and 4b), two acetylated derivatives (5a and 5b) and an amine (6). The synthesized compounds were obtained in yields ranging from 21 to 92% and were characterized by infrared spectroscopy, 1H, 13C NMR, and high-resolution mass spectrometry (ESI-HRMS). The antibacterial action of compounds 2a, 2b, 2c, 2d, 2e, 2f, 5a, and 5b was tested, the tests performed for the evaluation were the minimum inhibitory concentration (MIC) and the minimum bacteriostatic concentration (CMB), all products showed some biological activity except for compound 5b, which did not show any bioactivity within the concentrations analyzed.
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6
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CAROLINE SERIANI MODENEZE
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DEVELOPMENT AND VALIDATION OF GREEN ANALYTICAL METHODOLOGY FOR QUANTIFICATION OF ACETYLSALICYLIC ACID IN PHARMACEUTICAL FORMULATIONS
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Leader : SANDRO JOSE DE ANDRADE
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MEMBRES DE LA BANQUE :
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CASSIANA CAROLINA MONTAGNER RAIMUNDO
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FLAVIO SOARES SILVA
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SANDRO JOSE DE ANDRADE
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Data: 29 août 2022
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Afficher le Résumé
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Themes of sustainability and productivity are increasingly on the rise, due to the constant increase in demands and global guidelines leading to an increasingly sustainable world, always considering the gain of time. In the pharmaceutical field, these themes are also present, requiring methodologies increasingly faster, less toxic and less harmful to the environment. Given this scenario, one of the drugs with the highest production and consumption worldwide is Aspirin®, one of the oldest drugs in the pharmaceutical market. With its high-volume production and high consumption, consequently large volumes of analyses, high solvent expenditure and time required for such analyses, it is necessary and important to develop more agile methodologies and with less use of solvents. In addition to the reduction in the use of organics, the acetonitrile crisis that has been going on for some years is well known, having intensified in the last year and continued in the current year. Therefore, it is also important to work with methodologies that reduce or eliminate the use of acetonitrile as a solvent, eliminating the risk of compromising the analyzes due to the lack of this solvent. Thus, the analytical methodology was developed with a Chromolith High Resolution RP-18 100mm x 4.6mm monolithic block column, with 2 mL.min-1 of flow in a composition of 38% ethanol and 62% acidified water phosphoric acid, temperature 30°C, 10 μL injection volume in a run time of 3.5 minutes. For validation, selectivity, linearity, precision, accuracy, detection limits and quantification tests were performed. The selectivity presented results within acceptable standards, using Parteck® SI 200 as placebo, since there was no interference in the same retention time of acetylsalicylic acid. The calibration curve was linear, with a correlation coefficient greater than 0.99. Precision tests were evaluated by repeatability and reproducibility, which showed coefficients of variation of 0.36% and 0.55%, respectively. The accuracy also presented results within the acceptance criteria stipulated by RDC No. 166/2017, where recovery was evaluated at 80, 100 and 120% (400, 500 and 600 mg/tablet). Limits of detection and quantification were also evaluated, presenting values of 0.04 mg.mL-1 and 0.52 mg.mL-1. Therefore, the developed method can be successfully applied to Aspirin® tablet content analysis. In addition, the methodology developed was measured for green character, being evaluated by four metrics: green star, NEMI, AGREE, analytical echo scale and cost and time analysis. By the green star, the methodology developed meets the 5 principles of Green Chemistry against the 2 principles met by the pharmacopeial methodology. By NEMI, 3 filled quadrants compared to 2 quadrants of the original method and a score of 93 on the analytical echo scale compared to 80 points of the pharmacopeia. According to AGREE, the green methodology presented a score of 0.67 versus 0.35 of the original method, also proving the greater green character of the developed methodology. In addition, it presented a 72.5% reduction (from R$51.78 to R$14.24 considering 15 runs) in cost and 65% in time (from 10 minutes to 3.5 minutes) in relation to the pharmacopeial methodology.
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7
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RALF RICARDO RAMALHO JÚNIOR
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Removal of Ivermectin from aqueous matrices applying peanut shell biochar
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Leader : SANDRO JOSE DE ANDRADE
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MEMBRES DE LA BANQUE :
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FABIO DA SILVA LISBOA
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NATHALIA VIEIRA BARBOSA
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SANDRO JOSE DE ANDRADE
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Data: 19 déc. 2022
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The contamination of matrices in the environment by chemical compounds is a problem inherent to human development, since the generation of chemical residues is proportional to the techno-scientific advances of mankind, resulting in contamination of the most varied types of the most varied matrices. As for aquatic matrices, the class of emerging contaminants, compounds that have a potential ecotoxicological effect at low concentrations, in the order of ng L-1 and mg L-1, have gained the focus of researchers around the world. The presence of these kind of contaminants still aggravated by their persistence, since physicochemical characteristics can contribute to the fact that these compounds don’t degrade naturally or by conventional methodologies of treatment plants, culminating in the need to develop methodologies that can remove or degrade these compounds, such as the application of physical, biological or chemical methodologies. An example of material that can be applied for removal are the biochars, a type of charcoal obtained by the pyrolysis of biomass at high temperatures, producing a carbonaceous, amorphous material with characteristic porosity. In the present work, samples of biochar were applied for the removal of ivermectin, an antiparasitic quite representative in the veterinary market, in aqueous solutions. The material was obtained by Box-Behnken planning, seeking to explore biomass pretreatments. The same was characterized by the ATR-FT-IR techniques, which returned characteristic stretches of organic groups reported in the literature; SEM-EDS, in which the morphological variation of biochar types was observed; XRD, whose response was arrangements that varied according to the pre-treatment of the biomass. The removal assays were monitored by High Performance Liquid Chromatography and showed that higher pyrolysis and acidic treatment of biomass can improve the ivermectin removal. The average removal rate of the biomass pre-treated biochar, which obtaining method was optimized, was around 85%, fact that is assimilated with the characteristics of the obtained solid.
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Thèses |
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1
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ALLEY MICHAEL DA SILVA PROCÓPIO
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SYNTHESIS AND CHARACTERIZATION OF CERIUM OXIDE THIN FILMS SUPPORTED ON POROUS TITANIUM OXIDE CERAMIC FILTER FOR CATALYTIC APPLICATION IN REDOX GAS SYSTEMS
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Leader : FRANCISCO MOURA FILHO
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MEMBRES DE LA BANQUE :
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ANDRÉ FERNANDO DE OLIVEIRA
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CESAR RENATO FOSCHINI
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FABRÍCIO VIEIRA DE ANDRADE
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FRANCISCO MOURA FILHO
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MARCIO MARTINS LAGE JUNIOR
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MERCES COELHO DA SILVA
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Data: 18 févr. 2022
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Afficher le Résumé
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Compounds based on titanium dioxide (TiO2) and cerium dioxide (CeO2) have aroused the interest of the world scientific community for presenting multifunctional technological applications related to their properties and characteristics. Due to its crystalline structure, size and particle morphology, TiO2 is widely used in catalysis, photocatalysis, sensors and air and water purifiers. While CeO2, due to its high thermal stability, oxygen mobility in the crystal lattice, oxygen storage capacity (OSC) and redox potential, has been applied mainly in catalysis and systems for the purification of automotive gaseous emissions. In this work, a porous TiO2 ceramic filter (TCF) was processed by the polymeric sponge method (PSM), which was coated with CeO2 nanoparticles (CNP) in the form of thin film by the dip coating technique from a stock polymeric solution of cerium obtained by the polymeric precursor method (PPM). Through analysis of X-ray diffraction (XRD), infrared absorption spectroscopy (FTIR), ultraviolet and visible optical spectroscopy (UV-Vis), thermogravimetric (TG), differential thermal (DTA) and dilatometric (DIL), it was found that the TiO2 powder showed high crystallinity, rutile phase, tetragonal structure, belonging to the P4/mnm space group, low reflectance rate in the UV region and high in the visible region with accentuated behavior between 350-430 nm, band gap energy (Egap) of 3.22 eV for a direct allowed electronic transition and thermostable up to 1500°C. TCF in powder form were characterized by XRD, FTIR, UV-Vis and Raman spectroscopy. In addition to the rutile phase, material presented a second phase Ti3O5, orthorhombic structure, CmCm space group, more gradual reflectance behavior in the region 400-1000 nm and Egap of 3.03 eV. CNP were characterized by the same techniques besides TG and DTA. From the results of thermal analysis the material was calcined at 600ºC, 700ºC, 800ºC and 900ºC with isotherms of 120 minutes. CeO2 powder showed an increase in the degree of crystallinity with heat treatment above 600ºC, fluorite-like cubic structure, Fm3m space group, low reflectance rate in the UV region and high in the visible, with an accentuated behavior between 350-550 nm and Egap of 3.44 eV for a direct allowable electronic transition. TCF coated with CNP in thin film form were characterized by scanning electron microscopy (SEM). Micrographs indicated for TCF an interconnected structure, fragile due to the presence of hollow rods, some cracks and a rough surface, while the occurrence of the formation of the CeO2 film on the surface of the material after 10 depositions followed by calcinations at 900ºC, formation of islands, scales and layers until obtaining the film. For identification and quantification of Ti and Ce elements, the material was macerated and the powder was characterized by energy dispersive X-ray spectroscopy (EDS) and total reflection X-ray fluorescence (TXRF) with concentrations of 486.2 mg L-1 and 6.61 mg L-1, respectively. For the catalysis study, a gasoline vehicle and a gas analyzer were used for instant measurements of the conversion of CO to CO2. Catalytic ceramic filter obtained between 11% and 17% efficiency, however, low reducibility of Ce4+ in Ce3+ and oxygen vacancies in the network, low reaction temperature (41ºC) and large formation of condensed water (reaction by-product) were the main factors attributed to the low catalyst/CO interaction.
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NATHALIA VIEIRA BARBOSA
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Spectroscopic, Chromatographic and Chemometric Evaluation of the Degradation of Insulating Oils of Transformer
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Leader : FLAVIO SOARES SILVA
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MEMBRES DE LA BANQUE :
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ALBERTO CAMILO ALÉCIO
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MARIANA RAMOS DE ALMEIDA
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FLAVIO SOARES SILVA
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MILADY RENATA APOLINARIO DA SILVA
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ROSSANO GIMENES
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SANDRO JOSE DE ANDRADE
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Data: 30 juin 2022
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Afficher le Résumé
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Concern about environmental issues, the need for installations employing safety dielectric fluids, and the search for new methodologies for fluid maintenance of electric power machines using environmentally friendly technology are increasingly pronounced. Although the characteristics and variations of the physicochemical and electrical properties of insulating oils are well established, less attention has been paid to the molecular level to understand the nature of the thermal and electrical aging processes of these fluids. Thus, the objective of this work was to develop a fast, simple, and environmentally safe method to evaluate and monitor the quality of vegetable insulating oil (IVO) through multivariate control charts and Fourier Transform Infrared (FTIR) spectroscopy, in addition to evaluating the evolution of chemical compounds formed during the degradation of IVO subjected to electrical and thermal stresses, comparing with insulating mineral oil (IMO). In order to simulate the internal environment of a transformer before and after energization, samples of IVO and IMO were kept in contact with paper and copper and subjected to accelerated electrical and thermal aging processes, in which the samples were subjected to disruptive discharges (from 10 at 1000 discharges) and heating to 130 °C for up to 1080 hours, respectively. Subsequently, the composition of the fluids before and after electrical and thermal treatments was studied through the techniques of gas chromatography coupled with mass spectrometry (GC-MS) and FTIR spectroscopy and the evaluation of acidity, viscosity, and density of the samples. The results obtained showed that the developed control chart was able to identify IVO samples at oxidation levels outside the acceptable quality standards for plant insulating fluids in transformers; and those new compounds were formed, due to the degradation process of mineral and vegetable oils, under the conditions studied. Partial discharges contribute to the degradation of oils, and this effect was more pronounced in the IVO and the factor that most influences the degradation of these fluids is heating. The insulating paper acts to delay the aging of mineral and vegetable oils, while copper acts as a catalyst for fluid oxidation. The degradation of the antioxidant 2,6-di-tert-butyl-p-cresol (DBPC) from IMO is heating dependent, while the antioxidants tocopherol, stigmasterol, and sitosterol from IVO degraded even in systems that were not subjected to heating. The viscosity and acidity values of the oils increased, demonstrating the degradation under the conditions studied, and this effect was more pronounced in the IVO. In this way, the potential of FTIR spectroscopy, together with the strategy of control charts as a quick and simple tool for monitoring the quality of insulating fluids, allowing to guide the transformer maintenance plan, was demonstrated. The results contribute to studies carried out on insulating fluids and to companies involved in energy generation since with the results obtained, it will be possible to predict the aging time of oils, as well as make proposals to increase their useful life and to promote in a secures the replacement of mineral-type insulating fluid in transformers with vegetable oils, as they are more environmentally viable and have dielectric properties equivalent to IMOs.
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