Dissertations/Thesis

2024
Dissertations
1
  • GABRIELA LEMOS RIBEIRO DE SOUZA
  • "OTIMIZATION AND VALIDATION OF ANALYTICAL METHODOLOGY APPLIED TO HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY FOR THE CHARACTERIZATION OF THE RADIODRUG PSMA-1007 (18F)."

  • Advisor : ILDEFONSO BINATTI
  • COMMITTEE MEMBERS :
  • ILDEFONSO BINATTI
  • PATTERSON PATRICIO DE SOUZA
  • JUNIA DE OLIVEIRA ALVES BINATTI
  • CLEVERSON FERNANDO GARCIA
  • Data: Mar 1, 2024

  • Show Abstract
  • In Brazil, prostate cancer is the second most common type of malignant tumor in males. When this type of cancer is detected early, the chance of a cure increases significantly. In nuclear medicine, radiopharmaceuticals have been widely used for diagnostic and/or therapeutic purposes of the disease, such as in Positron Emission Tomography and Computed Tomography (PET/CT) examinations, respectively. When administered to the patient, the radiopharmaceutical is directed to an organ of interest due to the physiological or pathophysiological function of the disease. Prostate Specific Membrane Antigen marked with 18F, Prostate Specific Membrane Antigen (PSMA-1007(18F)) is a new radiopharmaceutical that has a positron-emitting radionuclide and is used for diagnostic purposes. In prostate cancer cells, PSMA is overexpressed, so PSMA molecules labeled with 18F will bind to them with high affinity. PSMA-1007(18F) accumulation in these cells allows PET images to be obtained revealing the presence of the tumor, as well as its extent and aggressiveness. The synthesis of this radiopharmaceutical is carried out via nucleophilic substitution, where the radiolabeled fluoride (18F-) attacks the precursor of the C54H64F3N9O18 reaction, and for its use to be safe, ANVISA recommends quality control tests that meet the Good Manufacturing Practices established by regulatory body.

    Aiming to optimize quality control, an analytical method implemented in High Efficiency Liquid Chromatography (HPLC) was developed to determine purity and radiochemical identification. The method elaborated in the present work, in relation to the methodology developed at CDTN based on the methodology described in the European Pharmacopoeia, presents some advantages such as replacing the organic solvent with a cheaper one, easier to acquire and with lower toxicity, changing the solvent aqueous by one that does not use buffer, avoiding column clogging and reducing the running time from 21 minutes to 10 minutes. As a result, there was less solvent consumption, less generation of chemical waste, a reduction in experiment costs and health risks, resulting in a more sustainable process. The analytical validation of the process was satisfactory as it met all the criteria required in RDC nº 166/2017 of ANVISA.

2
  • Luana Sousa de Oliveira
  • Electrochemical performance of composite electrodes based on Ce-UiO66/MWCNT for supercapacitors application 

  • Advisor : JOAO PAULO CAMPOS TRIGUEIRO
  • COMMITTEE MEMBERS :
  • JOAO PAULO CAMPOS TRIGUEIRO
  • FLAVIO SANTOS FREITAS
  • TULIO MATENCIO
  • Data: Mar 8, 2024

  • Show Abstract
  • The more efficient use of energy resources in order to reduce the world's dependence on non-renewable primary energy makes it necessary to invest in renewable energy sources. The research and development of efficient electrochemical energy storage systems is an important part of this step. Supercapacitors (SCs) have been extensively studied as energy storage devices due to their high power density and high cyclability.
    Although they were originally used for applications that require fast pulses of energy, improvements that increase the energy density of supercapacitors is a strategic issue in this field of research, which allows expanding its niche of applications such as hybrid electric vehicles, power supplies portable devices, pulsed electronic devices, among others.
    With the combination of faradaic and electrical double layer mechanisms, it is possible to obtain hybrid SCs that increase the energy density of cells to the level of batteries. These devices can be built using mainly faradaic/capacitive electrodes, pseudocapacitive materials and electrolytes containing redox additives.
    The individual properties of the electrode and electrolyte materials influence the performance of a supercapacitor. Thus, the scientific community has been researching materials that have greater electrochemical stability, such as metal-organic frameworks (MOFs). Due to their high specific surface area (> 1000 m2g-1) they have been considered promising for the preparation of SC electrodes, despite MOFs having low electrical conductivity values. This limitation can be overcome by preparing composites with conductive materials such as graphene, carbon nanotubes, among others. Redox electrolytes are active species capable of electrosorbing and transferring electrons at the electrode/electrolyte interface and have been efficiently used to increase the performance of supercapacitors, mainly with regard to capacitance and energy density.
    In the present work, the electrochemical performance of Ce-UiO66/multi-walled carbon nanotube (MWCNT) composite electrodes immersed in H2SO4 aqueous electrolyte containing cerium IV sulfate as redox species was evaluated. The results demonstrate that the electrode is stable in a wide range of potentials, supporting the high potential at which the redox reaction of the Ce3+/Ce4+ pair occurs (~1.2 V vs. Ag/AgCl/3.5M KCl). Under these conditions, high values of specific capacitance (380 F g-1) and energy density (155 kW g-1) were obtained.

2023
Dissertations
1
  • SARAH GABRIELA GUIMARÃES DE OLIVEIRA
  • STUDY OF ELECTROCHEMICAL COMPATIBILITY OF REDOX ADDITIVES WITH ZIF-67/CABON NANOTUBE ELECTRODES APPLIED IN SUPERCAPACITORS

  • Advisor : PAULO FERNANDO RIBEIRO ORTEGA
  • COMMITTEE MEMBERS :
  • PAULO FERNANDO RIBEIRO ORTEGA
  • RAQUEL VIEIRA MAMBRINI
  • JOAO PAULO CAMPOS TRIGUEIRO
  • TULIO MATENCIO
  • RODRIGO LASSAROTE LAVALL
  • Data: Feb 17, 2023
  • View Dissertation/Thesis  

  • Show Abstract
  • ZIF-67 is a metalorganic network formed by cobalt(II) metallic centers coordinated to four nitrogen atoms of four 2-methylimidazole ligands, in tetrahedral geometry and generating a sodalite structure. Is an attractive material for supercapacitor electrodes due to high specific surface area, high electrochemical stability and an active metal center. However, the low electrical conductivity of pristine ZIF-67 electrodes limits the specific capacitances and rate capabilities. An excellent strategy to increase the specific capacitances is the employ of electrolytes containing species which are capable to transfer electrons to surface electrodes. However, there are no studies that explore the compatibility of different redox species with ZIF-67 electrodes.

    In this work, electrodes composed by ZIF-67/multi-walled carbon nanotubes (NTC) were studied with three redox additives in alkaline medium: p-phenylenediamine (PPD), potassium hexacyanoferrate(II) (K₄[Fe(CN)₆]), and potassium iodide (KI). Cyclic voltammetry and charge/discharge galvanostatic measurements were employed to study the charge accumulation mechanism, specific capacitance, efficiency, and life cycle. The electrochemical results reveal that a little extension of redox reactions of iodine species on the electrode of ZIF-67/NTC. On the other side, redox additive with positive formal potentials (K₄[Fe(CN)₆]) is beneficial for boosting  the capacitance (747.1 F g–1 at 5.0 A g–1). With PPD, was also beneficial (148.0 F g–1 at 5.0 A g–1) and the favorable intermolecular interactions of this redox additive on the ZIF-67/MWCNT electrode surface deliver greater coulombic efficiency and cycling.

2
  • DALILA APARECIDA FARIA
  • SYNTHESIS AND CHARACTERIZATION OF g-C3N4 AND ITS APPLICATION AS A FIRE RETARDANT IN VEGETABLE FUEL

  • Advisor : EUDES LORENCON
  • COMMITTEE MEMBERS :
  • EUDES LORENCON
  • IVINA PAULA DE SOUZA
  • EMERSON FERNANDES PEDROSO
  • Data: Apr 28, 2023
  • View Dissertation/Thesis  

  • Show Abstract
  • In this work g-C3N4 (CN) was tested as a fire retardant, for application in forest fires. For this, CN was synthesized by the melamine thermal polycondensation method and its characterization was performed by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), absorption spectroscopy in the Fourier Transform infrared region (FT-IV), X-ray photoelectron excited spectroscopy (XPS), N2 adsorption/desorption isotherm and elemental analysis (CHN). The fire retardant property of CN was verified with burn tests using hay grass as fuel. The tests showed that g-C3N4 conferred fire retardant properties to the plant material, prolonging the burning time and decreasing the mass of residual fuel. These experiments also revealed that the fire retardancy of CN is more expressive in the increase of the burning time, than in the increase of the residual mass. The mixture of CN and NH4H2PO4 (MAP) was also evaluated in burning tests, obtaining as a result, the improvement of the fire retardant efficiency, in relation to pure CN. These data revealed the existence of a synergistic effect between CN and MAP, so that MAP promoted carbonization, increasing the residual mass, while CN slowed down the burning process. Thermal decomposition of CN was studied by FT-IV and TG (thermogravimetric analysis). The results showed that the material has high thermal stability, which gives it the property of forming a physical barrier during heating. In addition, it was noted that, given the increase in temperature, CN releases water molecules adsorbed in its porous structure, promoting cooling. This cooling can alter the pyrolysis process of the plant material, increasing the residual mass. In addition, CN decomposition can release diluent gases, reducing the concentration of combustible gases. With this information, a fire retardant mechanism for g-C3N4 was proposed.

3
  • GABRIEL SILVEIRA DE NOVAES
  • DEVELOPMENT OF AUTOMATIC ANALYTICAL METHOD FOR VIAL WALL SORPTIVE EXTRACTION ANALYSIS IN COMPREHENSIVE MULTIDIMENSIONAL GAS CHROMATOGRAPHY

  • Advisor : PATTERSON PATRICIO DE SOUZA
  • COMMITTEE MEMBERS :
  • PATTERSON PATRICIO DE SOUZA
  • EMERSON FERNANDES PEDROSO
  • LEILIANE COELHO ANDRE AMORIM
  • Data: May 2, 2023
  • View Dissertation/Thesis  

  • Show Abstract
  • With the great technological advances related to the analysis methods and detectors used to determine the analytes of a complex sample, the use of new sample preparation methods has become increasingly necessary to aid the analytical process. Within the sample preparation process, it is possible to highlight the performance of automated methods, which present lower statistical error compared to traditional ones, in addition to sparing the analyst, avoiding his direct contact with reagents and long periods of work. To assess the credibility of these new methods, ensuring that they will serve the proposed function, an analytical validation is carried out, determining their performance characteristics. This work brings the proposal to automate, optimize and validate a recent method of extraction and pre-concentration, the vial wall sorptive extraction (VWSE), being an efficient, miniaturized and clean method. For the analyzes, it was chosen to work with a multidimensional gas chromatograph, since its use brings the advantages of sensitivity at low concentrations, resolution and level of information obtained. The present work also aimed to develop the best procedure for making VWSE devices and to evaluate the statistical equivalence of the prepared devices, in addition to evaluating the possibility of their use in an automated methodology using a prototype of an automatic sampler available in the laboratory of the Centro Federal de Educação Tecnológica Minas Gerais. In the study, a standard of alkanes of known concentration was used in pure tetrahydrofuran solutions and in a mixture with Mili-Q® water. The VWSE devices were prepared in five different conditions using a lathe and a prototype developed to rotate the vials and spin coat them. The methodology proved to be efficient and its automation viable, with the VWSE devices made on a lathe at 250 rpm, horizontally with forced drying by a heat blower, presenting the best results among all the devices made. Different vials prepared under the same conditions showed excellent results, with statistical equivalence attested by the T and F tests performed for each alkane. From the evaluation of the viability of the automatic VWSE method, the optimization of the parameters involved in the process was carried out, adopting the optimal conditions of 50 °C during the process, 10 minutes of contact time between sample and extractor phase, 5 minutes of of liquid desorption and 100 μL of extracting solvent used. With the method then defined, a partial validation of the automatic VWSE method was carried out to assess its efficiency, determining its linearity, precision (repeatability and reproducibility), recovery (accuracy) and limits of detection and quantification. The method showed a linear, precise and exact response for the series of alkanes from decane to octadecane, reaching low detection and quantification limit values in the range of μg L-1

4
  • DANIEL ANTUNES BARBOSA
  • EXTRACTION CURVES ADJUSTMENT MODELS FOR MAGNETIZATION CALCULATION USING THE SQUID CRYOGENIC S700X MAGNETOMETER SOFTWARE

  • Advisor : EMERSON FERNANDES PEDROSO
  • COMMITTEE MEMBERS :
  • LUCIANO RONI SILVA LARA
  • EMERSON FERNANDES PEDROSO
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • Data: May 17, 2023
  • View Dissertation/Thesis  

  • Show Abstract
  • The growing interest, mainly in solid state physics, for the characterization of small samples or weakly magnetic samples, such as thin films, led to the development of measuring equipment technology whose state of the art is concentrated in equipment equipped with SQUID sensors (quantum interference device superconductor). In high-sensitivity magnetization measurements, some deviations in the measurements are common and may occur due to several factors, among which we can highlight the deviations resulting from the size and geometric shape of the sample, effects on the structure of the sample, uncontrolled displacement of the sample in the sample holders, effects of thermal expansion and contraction of the sample holder set, magnetic noise from different sources, among others. In this research, we magnetically characterized a sample of Dy2O3 dysprosium oxide, on which magnetization measurements were performed in a SQUID magnetometer as a function of the applied magnetic field, as well as magnetization measurements as a function of temperature variation. In this second type of measurement, measurements are generally carried out over a wide temperature range (5K to 300K), this causes the sample holder and the rod that supports the sample holder to undergo thermal expansion or contraction effects, causing that the sample leaves the correct position in which it was initially placed and due to this the measurement presents a deviation. The software that controls the equipment has three methods for the treatment of magnetization data extraction measurements. These methods were studied in order to verify which one would best suit the problems presented in the measurements, such as those described above, in particular the deviation due to thermal expansion or contraction. The standard adjustment method of the software (Multipol) in its fourth degree was sufficient to remove the deviation related to the contraction/expansion of the sample holder set. The FITRMS method was also studied, which had to be previously calibrated. With this adjustment method it was also possible to remove deviations in the measurements due to the thermal expansion effect that occurs in the sample holder set.

5
  • AMANDA ALVES SOARES
  • CRITICAL ANALYSIS OF TESTS FOCUSING ON METROLOGICAL ADEQUACY AND COLLECTION OF VALID DATA FOR ESTIMATION OF MEASUREMENT UNCERTAINTY
  • Advisor : PATTERSON PATRICIO DE SOUZA
  • COMMITTEE MEMBERS :
  • PATTERSON PATRICIO DE SOUZA
  • JANICE CARDOSO PEREIRA ROCHA
  • WELINGTON FERREIRA DE MAGALHÃES
  • Data: Jul 5, 2023
  • View Dissertation/Thesis  

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  • Metrology is a Science that is increasingly growing in importance in academic, industrial, and economic fields in developing countries around the world. The most current version of the 2017 ISO/IEC 17025 standard, the most used in quality management in laboratories that provide calibration, testing, and sampling services, reinforces this trend by drawing attention to two main points: risk management in these activities and estimation of measurement uncertainty. These two points are crucial in testing compliance assessments. The objective of this work is to understand these new trends, to make a bibliographic review of these points, and, finally, in a case study, to metrologically adapt routine tests so that it is possible to collect valid data for estimating the measurement uncertainty. The results obtained so far in the study of tensile tests are promising, since it is an easy-to-apply test, with good reproducibility and with the potential to be used in product quality control

6
  • ÍNGRID AMÉLIA DOS SANTOS MATUSINHO
  • Influence of starch type and crosslinking on the properties of biodegradable blends containing poly(butylene adipate-co-terephthalate).

  • Advisor : PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • COMMITTEE MEMBERS :
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • JOAO PAULO CAMPOS TRIGUEIRO
  • ELIANE AYRES
  • Data: Aug 18, 2023
  • View Dissertation/Thesis  

  • Show Abstract
  • In recent years, environmental issues are increasingly in evidence in society, especially in relation to plastic waste and environmental pollution related to them (UNEP, 2016). According to studies carried out by the WWF (World Wide Fund for Nature), Brazil is the 4th country that generates the most plastic waste in the world, producing about 11.3 million tons of waste, behind only the United States, China and India (WWF, 2019). The study and development of biodegradable polymers are a possibility to circumvent this problem (Muthuraj et al, 2017). Biodegradable polymers offer a number of advantages for environmental conservation as they degrade in a reasonably short period of time without causing environmental problems. In this work, it is proposed to produce and characterize blends of modified thermoplastic starch (TPSR) and poly(butylene-adipate-co-terephthalate)-PBAT, to evaluate the effect of the origin of the starch, having as source: Sweet Potato Starch and Cassava, and the influence of the variation of PBAT contents in the percentages of 10, 20, 30 and 40% m/m on the properties of the blends produced. The blends will be characterized in terms of thermal, structural, morphological and mechanical properties.

7
  • VENILTON MENEZES VIEIRA FERREIRA

  • DEVELOPMENT OF COMPOSITES BASED ON REINFORCING FIBERS AND POLYURETHANE MATRIX FOR COATING APPLICATIONS

  • Advisor : PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • COMMITTEE MEMBERS :
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • EMERSON FERNANDES PEDROSO
  • ANGELO ROCHA DE OLIVEIRA
  • Data: Aug 23, 2023
  • View Dissertation/Thesis  

  • Show Abstract
  •          O presente trabalho tem como proposta o desenvolvimento de um material compósito a base de PU reforçada com diversas fibras, entre elas as fibras de aramida, oriundas dos coletes de proteção balística, para reforçar o concreto utilizado para construção de postes de distribuição de energia. Pretende-se estudar propriedades físico-químicas e mecânicas do material compósito, além de aplicá-lo no concreto de modo a compará-lo sem e com reforço de PRF e observar a viabilidade da utilização em postes de companhias de distribuição de energia elétrica. Os materiais serão caracterizados mecanicamente por meio de ensaios de flexão, impacto Charpy e adesividade do PRF com o concreto. Além disso, também serão realizadas análises por microscopia eletrônica de varredura (MEV) da fratura dos materiais e análises de espectroscopia de absorção na região do infravermelho (FTIR), calorimetria exploratória diferencial (DSC) e de termogravimetria (TGA) do PU. 

8
  • JEFFERSON SAMUEL SANTOS
  • VALIDATION OF AN ANALYTICAL METHODOLOGY FOR DETECTION AND QUANTIFICATION OF CHLORPHENIRAMINE MALEATE IN THE EVALUATION OF CLEANING EFFICIENCY IN THE PHARMACEUTICAL CONTEXT

  • Advisor : PATTERSON PATRICIO DE SOUZA
  • COMMITTEE MEMBERS :
  • ILDEFONSO BINATTI
  • PATTERSON PATRICIO DE SOUZA
  • RAQUEL VIEIRA MAMBRINI
  • Data: Nov 14, 2023
  • View Dissertation/Thesis  

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  • Producing drugs requires strict adherence to national and international standards to ensure product quality and safety. Contamination can compromise the entire production process of a drug, and cross-contamination can occur if the cleaning process fails to remove residues of previously produced drugs on the same line. To avoid such problems, tools can be employed to assist in the quality control of all processes involved in drug preparation, including equipment and utensil cleaning. This study aimed to validate an analytical method using reverse-phase liquid chromatography (RPLC) to detect and quantify the active ingredient chlorpheniramine maleate in Resfedryl® medication and to evaluate the efficiency of cleaning process in removing the drug. The method employed a Zorbax SB-CN (250 x 4.6 mm 5 m) chromatographic column, a gradient elution in mobile phase that was composed of methanol and an aqueous solution of 0.07% (v/v) perchloric acid adjusted to pH 2.0, and a UV detector at a wavelength of 271 nm. The drug was satisfactorily eluted with a retention time of approximately 6.20 minutes. The method was found to be linear (R equal to 0.9998 and R2 equal to 0.9996), precise (%RSD between the intraday precision and the intermediate precision equal to 2,8%), accurate (recoveries between 91.48% and 94.24%), selective, relatively fast, and robust (except for the chromatographic column alteration parameter and for the solution stability parameter), with detection and quantification limits of 0.15 ppm and 0.46 ppm, respectively. The method was validated and can be applied to assess equipment and utensil cleaning quality after producing Resfedryl® medication.

2022
Dissertations
1
  • FABIANE CARLA LOPES
  • Automation sample preparation for amino acids chromatographic analysis

  • Advisor : EMERSON FERNANDES PEDROSO
  • COMMITTEE MEMBERS :
  • HELVECIO COSTA MENEZES
  • EMERSON FERNANDES PEDROSO
  • PATRICIA SUELI DE REZENDE
  • PATTERSON PATRICIO DE SOUZA
  • ZENILDA DE LOURDES CARDEAL
  • Data: Feb 3, 2022
  • View Dissertation/Thesis  

  • Show Abstract
  • .

2
  • JAQUELINE SILVA EVANGELISTA PIRES
  • APLICAÇÃO DE MOF DE FERRO E ÁCIDO TEREFTÁLICO NA REMOÇÃO DE FÁRMACOS EM EFLUENTES AQUOSOS

  • Advisor : RAQUEL VIEIRA MAMBRINI
  • COMMITTEE MEMBERS :
  • RAQUEL VIEIRA MAMBRINI
  • PATTERSON PATRICIO DE SOUZA
  • EUDES LORENCON
  • JULIANA CRISTINA TRISTÃO
  • Data: Feb 21, 2022
  • View Dissertation/Thesis  

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  • A ocorrência de fármacos nos corpos hídricos é considerada um problema ambiental emergente devido ao seu potencial risco toxicológico em organismos vivos, mesmo quando estes fármacos estão em baixas concentrações. Nesse contexto, a demanda crescente por água doce e a baixa eficiência na remoção dos fármacos por estações convencionais de tratamento de águas têm motivado diversas pesquisas na área e propiciado o desenvolvimento de vários materiais a serem utilizados em tratamentos alternativos em direção à sustentabilidade da água. Nesse contexto, as redes metalorgânicas, do inglês, metal organic framework (MOF), surgem como materiais promissores para a remoção e degradação de fármacos presentes na água.

    Com o objetivo de avaliar a aplicação de MOF à base de ferro e ácido tereftálico (MOF/FeBDC) nos processos de remoção e degradação eficaz de diclofenaco presente nos corpos hídricos, este trabalho, inicialmente, sintetizou a MOF/FeBDC conforme relatado em um trabalho recente do nosso grupo de pesquisa. A partir da análise por difração de raios X, por espectroscopia na região do infravermelho e da análise termogravimétrica, verificou-se que o material sintetizado corresponde ao mesmo produzido no trabalho de Oliveira, N. R et al. Em seguida, realizou-se testes para avaliar a cinética e a capacidade adsortiva da MOF/FeBDC em processo de adsorção de diclofenaco, obtendo-se resultados coerentes com o de outras MOFs relatadas na literatura. Por último, realizou-se testes de oxidação de diclofenaco, na presença da MOF sintetizada e de diferentes oxidantes. Nestes, verificou-se que a MOF/FeBDC aumentou, significativamente, a porcentagem de degradação do fármaco estudado na presença de peroximonossulfato de potássio (PMS), de 57% para 91%, sugerindo que a MOF produzida pelo nosso grupo de pesquisa apresenta uma elevada capacidade para atuar como catalisador para a ativação do oxidante PMS. Contudo, vários testes ainda serão realizados para avaliar esse potencial catalítico e os fatores que podem influenciar nessa catálise.

3
  • GABRIELA MAGALHÃES MAIA
  • SYNTHESIS OF TITANIUM DOPED METALLORGAN NETWORKS FOR OXIDATIVE DESULFURIZATION OF FOSSIL FUELS

  • Advisor : EUDES LORENCON
  • COMMITTEE MEMBERS :
  • DIANA QUINTAO LIMA
  • EMERSON FERNANDES PEDROSO
  • EUDES LORENCON
  • PATTERSON PATRICIO DE SOUZA
  • Data: Jul 15, 2022
  • View Dissertation/Thesis  

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  • The invention of gasoline and diesel engines and the technological advance for drilling wells intensified the exploration and use of oil. The combustion of petroleum releases sulfur compounds into the environment, which are harmful to humans, as well as from an economic and environmental point of view. In this context, oxidative desulfurization (ODS) emerges as an innovative technology for the production of diesel with low sulfur contents, under milder conditions than those necessary for the process known as hydrodesulfurization (HDS), commonly used in refining processes. The ODS reaction requires the presence of an oxidizing agent and a catalyst. Heterogeneous catalysts are very promising in this regard. Metal-organic frameworks (MOFs) are solid crystalline materials with high porosity formed by a strong bond between metal ion and organic ligand. MOF UiO-66, a metal-organic framework based on zirconium and terephthalic acid, is an interesting material for application in ODS processes. Thus, the general objective of this work is to synthesize pure and doped UiO-66 MOFs with different titanium contents, aiming at the oxidative desulfurization of a simulated petroleum matrix, using hydrogen peroxide as an oxidizing agent and diobenzothiophene (DBT) as a sulfur compound. The synthesis, characterization and application of these materials was the object of study, and since they proved to be very promising as catalysts, they were chosen for testing in ODS reactions within the scope of this work. Through the characterization techniques of X-Ray Diffraction (XRD), Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TG), X-Ray Fluorescence (FRX), Multimolecular Adsorption Theory (B.E.T.), Electron Microscopy of Scanning (SEM) and Energy Scattering X-Ray Spectroscopy (EDS) it was possible to observe the effectiveness of the proposed synthesis method and evaluate the properties of the synthesized materials. The results of the ODS assays varying the reaction parameters were obtained by analysis in GC-FID. For the standard reaction condition (50 mg of catalyst, 60 °C, O/S ratio=15), after 120 min of reaction, up to 96% of the DBT content was removed for 10TiMOF and the material could be reused. in 4 cycles without significant loss of activity.

4
  • AMANDA DE PAULA OLIVEIRA
  • VALIDATION OF SYNTHESIS METHODOLOGIES, DEVELOPMENT AND ANALYTICAL QUALITY CONTROL FOR RADIODRUG 18F PSMA - 1007

  • Advisor : ILDEFONSO BINATTI
  • COMMITTEE MEMBERS :
  • ILDEFONSO BINATTI
  • JUNIA DE OLIVEIRA ALVES BINATTI
  • PATRICIA SUELI DE REZENDE
  • PATTERSON PATRICIO DE SOUZA
  • Data: Jul 20, 2022
  • View Dissertation/Thesis  

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  • ABSTRACT Prostate cancer is the second most common type of cancer among men, if detected early the healing rate is almost 100%. Lately, nuclear medicine has become an important tool in the diagnosis and staging of prostate cancer, by using techniques such as PET/CT (Positron Emission Tomography and Computed Tomography). The use of PET tomography allows mapping the distribution of positron emitters administered to the patient, enabling early diagnosis of physiological changes. For that, it must be administered to a radiopharmaceutical whose radionuclide that constitutes it is a positron emitter. The radiopharmaceutical 18F PSMA-1007 ( 18F-labeled Prostate Specific Membrane Antigen), whose positron-emitting radionuclide is 18F, has become a viable target for prostate imaging and therapy, since PSMA, a membrane glycoprotein, is expressed in almost every type of prostate cancers. PSMA has its expression level about 1000 times higher in cancer cells when compared to the physiological levels found in other tissues, this makes PSMA a promising target for detection in imaging tests. The intensity of the accumulation of 18F PSMA-1007 in prostate tumors is positively correlated with other ways of evaluating and detecting prostate cancer, making the diagnosis more assertive. 18F PSMA-1007 can be obtained by a nucleophilic substitution reaction, where 18F reacts with a precursor, its use as a pharmaceutical preparation requires that quality control tests are carried out, which meet the Good Manufacturing Practices established by the regulatory body, in Brazil, ANVISA.

    Aiming the production and commercialization of this radiopharmaceutical in the CDTN, an attempt was made to establish the synthesis  and  quality control methodologies for this product . A procedure for the synthesis of the radiopharmaceutical 18F PSMA-1007 was implemented in the TRACERlab FX equipment, viable and capable of being performed according to Good Manufacturing Practices for Medicines. Analytical methodologies were developed and validated to certify complies with the quality control specifications. The analytical methodologies developed in this work in relation to other ones described, have the main advantage of the shorter execution time of the analyses, allowing the radiopharmaceutical to have its quality attested and to be released for use in patients in a shorter period of time.

5
  • MAÍRA LOPES SILVA DO COUTO
  • DEVELOPMENT OF A STARCH-BASED POLYMER SYSTEM FOR CONTROLLED RELEASE OF NUTRIENTS INTO THE SOIL.
  • Advisor : PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • COMMITTEE MEMBERS :
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • PATTERSON PATRICIO DE SOUZA
  • LUIZ CARLOS ALVES DE OLIVEIRA
  • Data: Aug 8, 2022
  • View Dissertation/Thesis  

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  • In view of the growing need to solve the environmental and economic problems related to the use of conventional fertilizers, this work proposes the development of a slow and controlled release system of starch-based nutrients. 
2021
Dissertations
1
  • JÉSSYCA CAROLINA SILVEIRA LOPES
  • DEVELOPMENT OF A POLYMERIC DEVICE FOR CONTROLLED RELEASE OF GALLIUM (III) ORALLY

  • Advisor : PRISCILA PEREIRA SILVA CALDEIRA
  • COMMITTEE MEMBERS :
  • PRISCILA PEREIRA SILVA CALDEIRA
  • ILDEFONSO BINATTI
  • MARIANA DE LOURDES ALMEIDA VIEIRA
  • Data: Jan 20, 2021
  • View Dissertation/Thesis  

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  • Por possuir propriedades muito similares as do ferro(III), que desempenha papel essencial para a vida humana, o gálio(III) é capaz de mimetizar esse íon em sistemas biológicos, participando assim de importantes processos celulares. O gálio(III), uma vez no organismo provoca alterações em algumas funcionalidades celulares, podendo, essas mudanças, ser positivas para o tratamento de câncer e infecções bacterianas.  Contudo, atualmente o gálio(III) está apenas disponível para administração por via intravenosa, que é menos confortável ao tratamento, além de, muitas vezes apresentarem um custo maior em comparação com as cápsulas. A administração por essa via é justificada pelas limitações na biodisponibilidade do gálio(III). Entretanto, visto que sistemas poliméricos têm se mostrado promissores para melhorar a biodisponibilidade de alguns princípios ativos e são amplamente utilizados na indústria farmacêutica, esse trabalho tem como objetivo principal o desenvolvimento de um sistema polimérico constituído por quitosana e alginato de sódio visando possibilitar a administração do gálio(III) por via oral para tratamento terapêutico de algumas enfermidades, incluindo o câncer.   

2
  • CAROLINA HELENA MARTINS
  • Development of blends based on thermoplastic / thermoset starch and polyester for applications in the plastics processing industry
  • Advisor : PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • COMMITTEE MEMBERS :
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • PRISCILA PEREIRA SILVA CALDEIRA
  • CLEVERSON FERNANDO GARCIA
  • Data: Jan 22, 2021
  • View Dissertation/Thesis  

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  • Os polímeros sintéticos, oriundos de materiais de origem fóssil e não biodegradável, em especial os plásticos, possuem importância em praticamente todas as áreas da vida moderna. Eles ganharam destaque por substituírem de forma eficiente, outros materiais como madeira, papel, vidro e metal. Os plásticos são populares porque são econômicos, leves, resistentes à oxidação, não são afetados fortemente pelo intemperismo, são versáteis e isolantes elétricos. O uso desses plásticos vem aumentando muito no mundo e devido a sua principal propriedade - a durabilidade - um sério problema acompanha o homem contemporâneo: a enorme quantidade de lixo produzida. Esse lixo pode levar mais de uma centena de anos para se decompor, resultando em problemas ambientais para a humanidade. Neste contexto, polímeros biodegradáveis como o amido e o poli(butileno succinato), PBS, podem ser inseridos como uma alternativa para substituir os tradicionais plásticos e diminuir assim o problema gerado pela produção de lixo e resíduos. Como alternativa a essas limitações, a associação de ambos os polímeros em blendas surge como uma possível solução. Além de diminuir o preço do produto final, uma vez que não se trabalha com o polímero sozinho, as blendas poliméricas permitem uma melhora nas propriedades mecânicas, na estabilidade do material e na diminuição do caráter hidrofílico do amido. Isso possibilita a aplicação desse material na indústria de plásticos para confecção de artigos de uso comercial e doméstico tais como canudos, pratos, talheres, embalagens, etc. Além dessa aplicabilidade, o material obtido é biodegradável e dessa forma, não agressivo ao meio ambiente.

3
  • GERALDO PAULO DO CARMO
  • "Prototipagem para análise de voláteis em Headspace por cromotografia gasosa

  • Advisor : PATTERSON PATRICIO DE SOUZA
  • COMMITTEE MEMBERS :
  • PATTERSON PATRICIO DE SOUZA
  • PRISCILA PEREIRA SILVA CALDEIRA
  • ILDEFONSO BINATTI
  • Data: Jan 28, 2021
  • View Dissertation/Thesis  

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  • In the various methods of analysis defined, a stage of sample preparation and extraction analytes is one that requires a lot of care and involves several steps using an expressive amount of organic solvents. In addition to being relatively time-consuming, they involve a considerable operational cost and generate a volume of waste to be treated. The development of new extraction methods that use little or no solvent is one of the most essential needs of laboratories analysis, botht for reduction of amount of waste, as well as for the reduction of the reduced time and also in the minimization of costs. The recent patent number BR1020180731670, obtained by INTECHLAB (Laboratory of Integrated Technologies of CEFET-MG) presented the development of an innovative technology for this purpose. The prototype called IT-FEX (IntraTube Flux Extraction Device), uses an internally polymeric phase coated glass tube (liner) to capture analystes present in liquid samples allowing the creation of a new prototype called HS-IT-FEX. This new prototype, which also uses an internally coated glass tube with PDMS polymer (polydimethylsiloxane), was developed to operate in headspace mode which allows the capture of volatile analytes. After trapping the analytes, these are thermally desorbed and analyzed by gas chromatography coupled with mass spectrometer as a detector. Laboratory tests with the new prototype HS-IT-FEX were carried out with solutions of PAHs (Polycyclic Aromatic Hydrocarbons), Persistent Organic Pollutants) that require attention regarding environmental monitoring. The preliminary results of this work demonstrate the possibility of trapping PAHs (such as naphthalene, acenaphtene, acenaphthylene and fluorene) from headspace generated from aqueous solutions without using organic and at low costs. Due to the lack of reproducibility of the chromatographic data in some tests, the need to improve the prototype was found, especially in the sealing system.

4
  • AMANDA SILVA OLYNTHO BAHIA

  • Evaluation of the efficiency of polyurethane coating for recovery and prolonging the useful life of equipment in the mining industry.

  • Advisor : PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • COMMITTEE MEMBERS :
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • EMERSON FERNANDES PEDROSO
  • LUZIA SERGINA DE FRANCA NETA
  • Data: Mar 3, 2021
  • View Dissertation/Thesis  

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  • O trabalho desenvolvido tem como objetivo testar poliuretanos como revestimentos para caixas alimentadoras de separadores magnéticos utilizadas na indústria de mineração, principalmente no processo de concentração magnética de partículas finas - 180 a 30 µm - e superfinas menores - que 30 µm - do rejeito de flotação e lamas de minério de ferro. Caixas com revestimento de borracha descartadas após o uso foram reformadas e receberam revestimento de poliuretano com diferentes durezas. Os equipamentos foram colocados em operação para avaliar a eficiência em proteger as caixas metálicas e será analisado o tempo em serviço dos equipamentos quando comparados às caixas de revestimento de borracha. Os dois tipos de poliuretanos foram submetidos a ensaios de caracterização para levantamento das propriedades mecânicas, físico-química e térmicas. Posteriormente, esses dados, juntamente com as propriedades da borracha utilizada no revestimento das caixas de alimentação informadas pelo fornecedor, serão comparados ao desempenho dos materiais em operação a fim de realizar um paralelo entre funcionalidade e características dos materiais.

5
  • MÁRCIA ADRIANA CORDEIRO DUARTE NUNES
  • Hydrothermal Synthesis of Molybdenum Oxide Nanofibers for Application in Selective Oxidation Reactions

  • Advisor : EUDES LORENCON
  • COMMITTEE MEMBERS :
  • EUDES LORENCON
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • RAQUEL VIEIRA MAMBRINI
  • Data: Mar 11, 2021
  • View Dissertation/Thesis  

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  • In recent years, molybdenum oxide catalysts have been prominent in applications involving oxidation of organic substrates with hydrogen peroxide. In this work, molybdenum oxide (NFMo) nanofibers were synthesized by simple hydrothermal treatment of bis (acetylacetonate) -dioxomolbdenum (VI) (MoO2 (acac) 2) in aqueous solution, without the need for surfactants or other growth directives. . This material was characterized and applied as a catalyst in oxidation reactions of various organic substrates in the presence of hydrogen peroxide or TBHP as oxidants.
    The synthesized NFMo were characterized by XRD, IR, Raman, SEM, TG, N2 Physisorption. The results confirmed the obtaining of MoO3 orthorhombic crystalline phase and allowed the observation of well defined and uniform morphology of the material. Subsequently, NFMo were applied in selective oxidation reactions of sulfur compounds such as DFS, MFS, DBT and BT, and showed excellent catalytic activity under mild reaction conditions. The catalyst also showed good oxidation efficiency of other organic substrates, such as pyridine, quinoline and 5-HMF, and was effective for olefin epoxidation in the presence of TBHP.
    The obtained results indicate that the studied catalyst presented great potential in selective oxidation reactions, proving very promising for applications in ODS reactions.

6
  • CINTHIA SOUZA DINIZ

  • Chemical modification of by reactive extrusion.

  • Advisor : PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • COMMITTEE MEMBERS :
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • RAQUEL VIEIRA MAMBRINI
  • PATTERSON PATRICIO DE SOUZA
  • Data: Mar 22, 2021
  • View Dissertation/Thesis  

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  • O presente trabalho foi desenvolvido para ampliar as possibilidades de aplicação do amido termoplástico (TPS) utilizando o método de extrusão reativa. O amido é um polissacarídeo produzido por algumas plantas para armazenar energia e é formado exclusivamente por moléculas de glicose unidas por ligações convalentes. Quando o amido é processado com glicerina, obtemos o amido termoplástico.
    Como objetivo principal temos a obtenção do amido termoplástico reticulado através do processo de extrusão reativa, utilizando diferentes ácidos carboxílicos, com elevada hidrofobicidaqde e propriedades mecânicas melhoradas quando comparado ao amido termoplástico não reticulado (TPS).
    Para o desenvolvimento deste trabalho, utilizamos a fécula de mandioca comercial, glicerina e diferentes teores de ácido cítrico para a extrusão reativa. As amostras foram preparadas utilizando 25% m/m de glicerina, teores de 0% até 5% m/m de ácido cítrico e processamento mecânico por extrusão. No processamento utilizando ácido tartárico, os teores foram de 1%, 3% e 5% m/m, sendo a escolha destes teores baseados nos resultados das amostras reticuladas com ácido cítrico.
    Todas as amostras foram submetidas as análises de espectroscopia de absorção na região do infravermelho, determinação da razão entre bandas de carbonila / carbono – hidrogênio e eter / carbono – hidrogênio, ângulo de contato, intumescimento, análise termogravimétrica (TGA), calorimetria diferencial exploratória (DSC), ensaio mecânico de tração, microscopia eletrônica de varredura (MEV) e difração de Raios – X.
    Como conclusões parciais, temos a possibilidade de utilização do processamento de extrusão reativa para reticulação do amido em uma única etapa. As amostras que obtiveram melhores resultados nas análises realizadas, se encontram entre a concentração de 1% a 2,5 ~ 3% m/m de ácido cítrico. Entretanto, é observada a dificuldade do processamento e o controle dos paramêtros de processo, como relatados em outros estudos.

7
  • SIMONE ELZA DOS SANTOS TEODORO

  • EVALUATION OF THE ADDITION OF TYPE I COLLAGEN IN THERMOFIXED ADHESIVE BASED ON POLYURETHANE
  • Advisor : PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • COMMITTEE MEMBERS :
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • PAULO FERNANDO RIBEIRO ORTEGA
  • EMERSON FERNANDES PEDROSO
  • Data: May 21, 2021
  • View Dissertation/Thesis  

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  • In this work was synthezed an adhesive based on polyurethane from the prepolymer 2,4-toluene diisocyanate (TDI) and  2,4-dimethyl-thio-toluenediamine (DMTDA) as chain extender. The partial replacement of the extensor by collagen I was performed. Samples were produced and their physical, mechanical, morphological and thermalproperties  were evaluated. The results of the mechanical tests have showed that there are an increase in the percentage of the rigid phase leading to an increase in tensile strength and resistance to organic solvents. The morphological analyzes indicated that the collagen increased the percentage of the rigid phase and promoted the formation of smaller microcells, more evenly distributed in the adhesive. Thermogravimetry analyzes indicated the presence of two stages of degradation, referring to the rigid and flexible phases, respectively. Differential exploratory calorimetry tests indicated that the collagen formulation showed a degree of christality confirmed by the DRX.
8
  • DIOGO AUGUSTO FONSECA GONÇALVES
  • SYNTHESIS AND CHARACTERIZATION OF COMPOSITE MATERIAL OF GRAPHIC CARBON NITRON AND NIOBUS OXIDE AND ITS APPLICATION AS A CATALYST IN OXIDATION REACTIONS

  • Advisor : EUDES LORENCON
  • COMMITTEE MEMBERS :
  • RAQUEL VIEIRA MAMBRINI
  • PAULO FERNANDO RIBEIRO ORTEGA
  • EUDES LORENCON
  • Data: May 26, 2021
  • View Dissertation/Thesis  

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  • .

9
  • ALEXANDRE COELHO RODRIGUES GOMES
  • Computational prediction of the stability and decomposition
    barriers of neutral molecular polynitrogens.

  • Advisor : BRENO RODRIGUES LAMAGHERE GALVAO
  • COMMITTEE MEMBERS :
  • WILLIAN RICARDO ROCHA
  • BRENO RODRIGUES LAMAGHERE GALVAO
  • LUÍS PEDRO VIEGAS
  • MATEUS XAVIER SILVA
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • Data: Jun 25, 2021
  • View Dissertation/Thesis  

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  • This work presents a broad study on the stabilities of several neutral molecular polynitrogens (polyN), with sizes six, eight and ten, focusing in theoretically predicting their usability as high-energy-density materials (HEDMs). If stable enough to be synthesized and stored, these systems may be used as a green source of energy. However, it is very difficult to obtain these structures under mild experimental conditions. One of the main factors that can help this sort of analysis is the predicition of the activation energy barriers of these structures towards unimolecular decomposition. The latter was the basis of the discussions presented throughtout the text. The calculation methodology applied for all the polyN was based on density functional theory (DFT), using exchange and correlation functionals that are known for their high accuracy in predicting energy barriers heights (M06-2X and SOGGA11-X). This made possible a direct and fair comparison between all molecules analysed. The path taken towards achieving this goal started with the search for transition states (TSs) that connected the initial structures to unimolecular decomposition. After finding the TSs, an intrinsic reaction coordinate calculation was carried out for each polyN in order to confirm the decomposition mechanism found. For the most promising structures, a reaction dynamics study was made, in order to check other possible decomposition routes. For this initial and exploratory part of the work, the SOGGA11-X/def2-SVP level of theory was used. A refinement of the results was then performed at the M06-2X,SOGGA11-X/def2-TZVPP levels, being the energies zero pointed corrected. For a structural and electronic analysis of the systems, the average bond lenghts, average bond orders, HOMO-LUMO gaps and asphericities were calculated. From this analysis, it was possible to classify the structures in chains, rings, cages and prismatic cages ones and achieve a correlation between the systems and their energy content. However, it was not possible to assess a clear correlation between the activation energy barriers of the structures with the calculated structural and electronic properties. The results indicate that the prismatic caged polyN can be expected to present higher energy densities and be more stable with respect to unimolecular decomposition. And finally, specific structures could be selected as potential candidates for use as HEDMs.

10
  • EMILAY BAESSA TEIXEIRA DIOGO
  • Coordination compounds containig Gd(III), Tb(III), Dy(III) and Ho(III) lanthanide ions and oxamate ligands: Synthesis and photophysical studies of potential molecular magnets.

  • Advisor : EMERSON FERNANDES PEDROSO
  • COMMITTEE MEMBERS :
  • EMERSON FERNANDES PEDROSO
  • EUDES LORENCON
  • HUMBERTO OSORIO STUMPF
  • LEANDRO FERREIRA PEDROSA
  • Data: Sep 10, 2021
  • View Dissertation/Thesis  

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  • The synthesis and characterization of the following two oxamate type ligands: 4- methylphenylene(oxamate), hereby named 4-mpo, and tetrabutylammonium N-4- methylphenylene(oxamate), named Bu4N+(4-mpo) is herein described. These ligands were used for preparing four coordination complexes with lanthanide ions Gd(III), Tb(III), Dy(III) and Ho(III). The achieved coordination compounds were characterized via infrared vibrational spectrometry, thermogravimetric analysis, polycrystal X-ray diffraction, elemental analysis and melting point. The structure of the dysprosium-based compound was elucidated by X-ray diffraction techniques. Optical property studies were performed and the quantum yield of the coordination compounds in solution and in solid were determined. 

11
  • GABRIELA MENTA ALVIM
  • PROPOSAL OF ALTERNATIVES FOR THE TREATMENT OF REAL EFFLUENT FROM A PHARMACEUTICAL INDUSTRY

  • Advisor : ILDEFONSO BINATTI
  • COMMITTEE MEMBERS :
  • PATTERSON PATRICIO DE SOUZA
  • ILDEFONSO BINATTI
  • LUZIA SERGINA DE FRANCA NETA
  • MIRIAM CRISTINA SANTOS AMARAL MORAVIA
  • Data: Sep 29, 2021
  • View Dissertation/Thesis  

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  • Rapid population growth and global industrialization have resulted in the progressive generation of industrial effluents with significant concentrations of emerging contaminants or micropollutants such as drugs, personal care products, hormones, and surfactants. These pollutants are considered persistent and difficult to degrade in Wastewater Treatment Plants (WWTP), reaching the aquatic environments after treatment and being found in freshwater. The pharmaceutical wastewaters, in addition to persistence, can cause toxicity to aquatic organisms and inhibit biological activity in wastewater treatment reactors. The research aims to characterize real pharmaceutical wastewater, assessing the efficiency of its current treatment and, if necessary, propose improvements to obtain cost reduction and compliance with the disposal rules. An environmental risk assessment will be carried out to assess the effluent toxicity. The industrial effluent characterization was carried out by compiling historical data of quality parameters contained in laboratory reports of 2019. Historical production data were used to understand the type and quantities of drugs manufactured, the active ingredients and excipients used and, thus, infer about the wastewater's toxicity and biodegradability. The greatest consumption of industrial input was in July and August 2019, with the most consumed principles: anhydrous glucose (33.9%), paracetamol (20.6%), dipyrone (13.9%), benzoate benzyl (8.2%), sodium chloride (6.6%), sodium citrate (4.9%) and potassium chloride (2.6%). The treated effluent at the company's WWTP presented low compliance for COD and pH, being characterized as slightly acidic and, therefore, it was outside the ideal range for the anaerobic treatment used. The effluent temperature, despite following the established limit, was also below the ideal range for the applied treatment. It was possible to infer that the anaerobic reactor used is operating in an acidogenic phase, presenting reduced efficiency when compared to the methanogenic phase, which would be preferable. The treatment has not been effective when presenting COD values higher than the established limit, in addition to the production of bad smell in the area. Starting errors and reactor conditions seem to imply unwanted costs and reduced efficiency.

     

12
  • DÊNIS FERNANDO ALVARENGA
  • DEVELOPMENT OF FLEXIBLE ELECTRODES OF CARBON NANOTUBE/CELLULOSE NANOFIBRILS FOR APPLICATION IN REDOX SUPERCAPACITORS

  • Advisor : PAULO FERNANDO RIBEIRO ORTEGA
  • COMMITTEE MEMBERS :
  • EUDES LORENCON
  • GARBAS ANACLETO DOS SANTOS JUNIOR
  • MARIO GUIMARAES JUNIOR
  • PAULO FERNANDO RIBEIRO ORTEGA
  • RODRIGO LASSAROTE LAVALL
  • Data: Sep 29, 2021
  • View Dissertation/Thesis  

  • Show Abstract
  • Currently, supercapacitors (SCs) stand out for being energy storage devices with high-power density. However, to maximize its niche of applications, many efforts have been made to increase its energy density compared to batteries and fuel cells. Furthermore, with the growing demand for miniaturized, thin and flexible electronic devices, the development of electrode materials that meet these characteristics is necessary. In this work, thin and flexible electrodes were developed, called buckypapers (BPs), composed of carbon nanotubes/cellulose nanofibrils (CNT/CNF), in a 1:1 mass ratio, for application in redox SCs. The CNFs used, α-CNFs, β-CNFs and γ-CNFs, were obtained, respectively, from three different cellulosic matrices: Eucaliptus sp, Pinus sp and Bambusa vulgaris. The incorporation of these low cost and biodegradable cellulosic components was carried out to optimize the mechanical and surface properties of BPs. The films were also evaluated for their morphological, thermal and electrical properties. As a result, all BPs showed thermal stability up to 132 ºC, electrical conductivity greater than 0.15 S cm-1 and an increase of 125% in tensile strength and 67% in maximum tensile strength, compared to a BP/without cellulose used as reference. Finally, the BPs were analyzed as redox SCs electrodes in two media: one of them an alkaline medium containing the redox additive potassium hexacyanoferrate(II) (0.1 M K4[Fe(CN)6] in 3.0 M KOH) and the other, an acidic medium containing methylene blue AM as an additive (0.07 M AM in 1.0 M H2SO4). All BPs, α-BP, β-BP and γ-BP, prepared with the different CNFs are stable in acid and basic electrolytes and mediate electron transfer from redox additives. The cell constructed with γ-BP immersed in alkaline redox electrolyte stands out with a specific capacitance (at electrode level) of 167.64 F g-1 (a 5 mA), with a capacitance retention of 98.15% after 12000 galvanostatic charge/discharge cycles. Using the acid redox electrolyte, the best performance in terms of specific capacitance was obtained for α-BP (40.85 F g-1 to 5 mA), with 80.53% capacitance retention after 12000 cycles.

13
  • KÉLRIE HESSEM DE ARAÚJO MENDES DA COSTA
  • DEVELOPMENT OF HYBRID SUPERCAPACITORS USING COMPOSITE ELECTRODES OF CARBON NANOTUBE/CELLULOSE NANOFIBRILS AND GEL POLYMER ELECTROLYTES

  • Advisor : PAULO FERNANDO RIBEIRO ORTEGA
  • COMMITTEE MEMBERS :
  • RODRIGO LASSAROTE LAVALL
  • EMERSON FERNANDES PEDROSO
  • PAULO FERNANDO RIBEIRO ORTEGA
  • SIDNEY NICODEMOS DA SILVA
  • Data: Sep 30, 2021
  • View Dissertation/Thesis  

  • Show Abstract
  • Supercapacitors (SCs) are electrochemical energy storage devices that have a high specific power but retain a low energy density. Strategies to overcome this limitation have been developed in recent years, such as the addition of redox compounds to the electrolyte. Furthermore, in order to expand the number of practical applications of SCs, the construction of solid polymeric electrolytes is of interest, as it allows the assembly of flexible cells and the construction of miniaturized devices in various geometric formats. In this sense, the present work aimed to develop hybrid SCs built with composite electrodes of carbon nanotubes/cellulose nanofibrils and redox gel polymeric electrolytes based on poly(vinyl alcohol). Polymeric electrolytes were added with different redox compounds: methylene blue, hydroquinone and indigo carmine. Polymeric electrodes and electrolytes were characterized, solid cells employing two redox additives (biredox) were constructed and their electrochemical performance evaluated. Finally, the biredox SC achieved specific capacitance, energy density and power density of 7.46 F g-1, 0.55 Wh kg-1 and 360.17 W kg-1, respectively, being able to retain 81.0% of its initial capacitance at the end of 2000 evaluated cycles.

14
  • JHONATAN BISPO DE OLIVEIRA
  • nada

  • Advisor : PATTERSON PATRICIO DE SOUZA
  • COMMITTEE MEMBERS :
  • ZENILDA DE LOURDES CARDEAL
  • ANA MARIA DE RESENDE MACHADO
  • ILDEFONSO BINATTI
  • PATTERSON PATRICIO DE SOUZA
  • Data: Dec 8, 2021
  • View Dissertation/Thesis  

  • Show Abstract
  • nada

2020
Dissertations
1
  • DESIRÉE MARIANNE SALES SILVEIRA
  • New sample preparation device: validation of a fast, inexpensive and ecological method for analyzing aqueous samples by gas chromatography

  • Advisor : PATTERSON PATRICIO DE SOUZA
  • COMMITTEE MEMBERS :
  • PATTERSON PATRICIO DE SOUZA
  • ILDEFONSO BINATTI
  • PATRICIA SUELI DE REZENDE
  • Data: Mar 4, 2020
  • View Dissertation/Thesis  

  • Show Abstract
  • In chemical analyses, sample preparation is the most time consuming step of all analytical process and the main source of errors in the final result. Available methods such as Solid Phase Extraction (SPE) and Solid Phase Microextraction (SPME) are usually laborious, expensive and fragile, like SPME fibers, which are highly sensible and may break with a little mistake, stopping its use. Therefore, improvements in the process are desirable and important to achieve better analytical results. This work presents an innovative one-step and solvent-free method of aqueous sample preparation for gas chromatography, using Poly(Methyl MethAcrylate) (PMMA) as extractor phase, for the trapping of Volatile Organic Compounds (VOC) from aqueous samples. The process consists of a sample flow through the inside of a liner internally coated with PMMA. This flow is maintained until the reach of the thermodynamic equilibrium time of the analyte between the PMMA and the aqueous matrix. After the absorption of the analyte by the polymeric phase, the liner is then inserted into the gas chromatograph for desorption and chromatographic separation. The method was tested using an aqueous solution of 1-dodecanol, a mix containing 13 alkanes and a standard containing 16 pesticides. The GC-MS system was composed by an Agilent 7890A GC (Supelco HP-5MS capillary column) coupled with an Agilent 5975B Single Quadrupole MSD, under SCAN mode. The method was successfully able to identify all the analytes, and it was also optimized in order to improve signal’s resolution, reduce the baseline and decrease signals from interferes. It was evaluated how the molecular weight of PMMA affects the absorption power, comparing the polymers of 120,000 g mol-1 and 350,000 g mol-1, and it was found no significant differences, however the PMMA of higher molecular weight was more stable and resisted thermal degradation by more chromatographic analysis than the PMMA of lower molecular weight. The method was validated for the analysis of five pesticides - heptachlor, aldrin, heptachlor epoxide, endosulfan and dieldrin - obtaining LOD (Limit Of Detection) values in the range of 1,46 to 4,26 μg L−1 and LOQ (Limit Of Quantitaion) values in the range of 5,95 to 8,70 μg L−1 . The accuracy of the method was assessed by studying intra-day repeatability, obtaining RSD (Relative Standard Deviation) values in the range of 5.60% to 16.70%. The linearity of the method was investigated with the construction of the analytical curve for the five pesticides, obtaining R2 values up to 0,99018. The new method is a viable, cheap, fast, and safe alternative for extraction and pre-concentration of volatile analytes in aqueous samples for gas chromatography analysis, besides being an innovative application, that redefines a liner’s function in the equipment.

2
  • Anna Karolina Vilela Freitas
  • Development of a method for the extraction of collagen from the waste of the frog meat industry and evaluation of the product for industrial use

  • Advisor : PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • COMMITTEE MEMBERS :
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • ILDEFONSO BINATTI
  • CAMILA SILVA BREY GIL
  • Data: Mar 13, 2020
  • View Dissertation/Thesis  

  • Show Abstract
  • Collagen is a fibrous protein capable of providing resistance and elasticity to the anatomical structures which are present as a constituent. Several uses can be attributed to collagen materials, which stand out in the cosmetics, food and pharmaceutical industries. Most collagen is extracted from mammalian leather. However, the outbreak of diseases in this type of animal leads us to the need to seek alternative sources for obtaining it. Among the potential substitutes, amphibians stand out, specifically the bullfrog. With the increase in the consumption of this animal, a noble waste is generated, little used, which needs adequate disposal options. The present work aims to propose an efficient method for the extraction of collagen from bullfrog residue and to evaluate it's performance as a substitute for collagen in mammals. Collagen extraction was successfully performed, with an average yield of 0.01353 g / g of skin. The products obtained were characterized by FTIR, TG and DSC, presenting characteristic results for a collagen sample, according to the literature. The pH varied from 4 to 6.5 and the average ash content was less than 2%. The mechanical behavior of the collagen film was obtained by the traction test. The content of total nitrogen and crude protein in the skins, feet and extracted collagen was determined, with an average value of 57.4% for skin collagen and 55.7% for feet collagen. The results show that it is possible to obtain hydrolyzed collagen from the skin of a bullfrog. The product presented interesting characteristics that are prerequisites for applications in various industrial sectors.

3
  • JÂNIA DOS SANTOS ROSARIO
  • Synthesis and characterization of gallium (III) and bismuth (III) complexes beraring bioactive ligands

  • Advisor : PRISCILA PEREIRA SILVA CALDEIRA
  • COMMITTEE MEMBERS :
  • EUDES LORENCON
  • PRISCILA PEREIRA SILVA CALDEIRA
  • WILLIAN XERXES COELHO OLIVEIRA
  • Data: Jun 5, 2020
  • View Dissertation/Thesis  

  • Show Abstract
  • Nowadays there has been an expansion of gallium and bismuth compounds with therapeutic potential. Gallium (III) is able to mimic iron(III) by replacing it at various iron-dependent sites, causing disruption of cell replication, which is an important mechanism against tumor cell proliferation. Bismuth(III), in turn, has been used to treat gastrointestinal disorders, ulcers and bacterial infections, especially those caused by the bacterium Helicobacter pylori. Bismuth has the great advantage of low cytotoxicity. Thus, this work consists of combining the pharmacological properties of these metallic ions with bioactive ligands.

    Thus, this work consists of combining the pharmacological properties of these metal ions with that of bioactive ligands. This work presents the synthesis, physico-chemical characterization and spectroscopic studies of three new compounds having bismuth(III) or gallium(III) as the metal center with the quinolone families (nalidixic acid and ciprofloxacin) and quinolines ( 8-hydroxyquinoline). The compounds are: [BiCl3(CFX)3] –1, [Bi(8-hq)2(Hcip)]Cl‧2H2O - 2, [Ga(NDX)3]∙4H2O - 4. One of the compounds present in this work is already known in the literature, [Ga(8-hq)3] - 3 and was prepared to be used in the future as a reference for cytotoxic tests.

4
  • CLARA VIEIRA DINIZ
  • Study of the composition, morphology, and catalytic activity of materials based on waste from single-dose coffee capsules for use in environmental decontamination processes.

  • Advisor : RAQUEL VIEIRA MAMBRINI
  • COMMITTEE MEMBERS :
  • RAQUEL VIEIRA MAMBRINI
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • PRISCILA PEREIRA SILVA CALDEIRA
  • Data: Jun 19, 2020
  • View Dissertation/Thesis  

  • Show Abstract
  • With the growth in coffee consumption in the form of single-dose capsules, there is also an increase in the inappropriate disposal of these capsules in landfills and dumps. To find a solution, the reuse of the used single-dose capsules was studied in this work. For this, capsules of the Dolce Gusto® (DG) and Nespresso® (NS) brands were selected and processed by chopping, grinding and heat treatment. The processed capsules were characterized by X-ray diffraction, X-ray fluorescence spectroscopy, scanning electron microscopy, X-ray dispersive energy spectroscopy, thermogravimetry and absorption spectroscopy in the infrared region. From the characterizations, it was observed that DG capsules are composed mainly of polypropylene and small concentrations of Fe and Ti, metals active in Fenton-like processes and photocatalysis, and NS capsules are composed mainly of Al and small concentrations of Fe. To evaluate the catalytic activity of the capsules in the removal of nitrogenous and sulfur compounds from petroleum, the capsules were used in two-phase reactions of the Fenton type using models of nitrogenous contaminants (quinoline) and sulfur (dibenzothiophene) as substrates. The presence of nitrogenous and sulfur substances in fuels is a problem during the refining process and after burning, an environmental problem. The test results showed that the capsules removed up to 32% quinoline by oxidation, and 40% dibenzothiophene by adsorption. Reuse tests on quinoline oxidation showed that heat-treated capsules are more stable than ground and perforated ones. Photocatalytic tests were also carried out in an aqueous medium to remove methylene blue, a contaminant of textile effluents. Both brands removed 99% of the substrate under UV light, while under visible light, the DG capsule removed about 30% and NS 60% of the dye.

5
  • MARIANA ERCULANO DA FONSECA
  • Síntese hidrotermal de nanopartículas baseadas em cério e nióbio: caracterização e avaliação da atividade catalítica

  • Advisor : RAQUEL VIEIRA MAMBRINI
  • COMMITTEE MEMBERS :
  • RAQUEL VIEIRA MAMBRINI
  • EUDES LORENCON
  • ANGELA DE MELLO FERREIRA
  • Data: Jun 26, 2020
  • View Dissertation/Thesis  

  • Show Abstract
  • O interesse pela síntese de materiais nanoestrutrados tem aumentado consideravelmente nos últimos anos em decorrência de determinadas propriedades apresentadas por esses materiais e que não são observadas em dimensões macro. A síntese hidrotermal é uma das alternativas de rota de síntese adotadas para a obtenção de nanopartículas de diversos materiais. Com base nisso, no presente trabalho, prepararam-se nanopartículas baseadas de óxido de cério (CeO2) pelo método hidrotermal variando-se a temperatura de calcinação em 350 e 550 °C dando origem aos materiais nomeados como CeO2/350 e CeO2/550. Também foram sintetizados, pelo método hidrotermal, materiais baseados em cério e nióbio variando-se a razão molar de Ce/Nb em 1:1, 2:1 e 3:1 gerando os materiais nomeados CeNb/1:1, CeNb/2:1 e CeNb/3:1. Os materiais sintetizados foram caracterizados por DRX, IV, TG, MEV/EDS e FRX que comprovaram a obtenção do CeO2 e a presença do Nb nos materiais CeNb em teores próximos aos propostos, além de possibilitar a observação da morfologia dos mesmos. Posteriormente, esses materiais foram aplicados em reações de adsorção e degradação do corante azul de metileno (AM), onde observou-se que os materiais não possuem uma grande capacidade adsortiva para o corante, entretanto apresentaram promissores resultados de degradação atingindo 100% de descoloração da solução de AM em 30 min e além de manterem-se ativos após 4 ciclos de reuso ainda com grande atividade. Os resultados obtidos mostraram que os materiais sintetizados podem ser promissores para aplicação em outras reações de catálise.

6
  • ISABELLE KARINE VIEIRA GONÇALVES
  • Synthesis, structural and physical-chemical characterization of monomers and coordination polymers of copper containing isophthalate and N,N-donor ligants.

  • Advisor : PRISCILA PEREIRA SILVA CALDEIRA
  • COMMITTEE MEMBERS :
  • PRISCILA PEREIRA SILVA CALDEIRA
  • RAQUEL VIEIRA MAMBRINI
  • RENATA DINIZ
  • Data: Jul 3, 2020
  • View Dissertation/Thesis  

  • Show Abstract
  • The study and preparation of new copper compounds have high scientific relevance, since they have a wide application area, such as magnetic characteristics, pharmacological potential, catalytic action, among other properties of technological interest. Copper compounds have great structural versatility being capable of forming mono and multinuclear complexes with different geometries and properties. The chemical reaction between copper(II) and the ligands isophthalate (ipa) and 1.10-phenanthroline (phen) by two different synthetic routes, led to the formation of two new compounds. One compound consisted of Polymer of coordination, {[Cu(ipa)(phen)(H2O)]‧DMF} n, in which the ligand ipa acts as a bridge between adjacent copper ions connecting to the metal centers in mono and bicoordinate way by the carboxylate groups. The other compound consisted of two cocrystallized monomers, [Cu(Hipa)(phen)(H2O)2] ClO4·[Cu(ipa)(phen)(H2O)2]‧2H2O, in which in one monomer the ligand ipa is found monoprotonated requiring a perchlorate as a counter-ion and in the other complex, the ipa is totally deprotonated, generating a neutral complex. On the other hand, replacing phen with the 2,2'-bipyridine (bpy) and following the same synthetic procedures is only formed a coordination polymer, {[Cu(ipa)(bpy)]‧2H2O}n, as a principal product independently of the adopted procedure. Interestingly, a copper(I) tetranuclear cluster, [Cu42-Cl)4(bpy)2], was formed as a by-product of the hydrothermal reaction to obtain {[Cu(ipa)(bpy)]‧2H2O}n. Although the cluster has been previously related, it was produced in the shortest reactive time than that listed in the literature. Moreover, the complex (Hampy)2[CuCl4], where ampy = 2-aminopyridine, was obtained by a distinct synthetic route that the reported in the literature. All prepared complexes were physical-chemical and structurally characterized by elemental analysis, atomic absorption, vibrational spectroscopy and X-ray diffraction by monocrystal.

     

7
  • TIAGO MENDES DE SOUZA
  • Water Adsorption Study in Silicon-Aluminum Nanoclusters.

  • Advisor : BRENO RODRIGUES LAMAGHERE GALVAO
  • COMMITTEE MEMBERS :
  • BRENO RODRIGUES LAMAGHERE GALVAO
  • EUDES LORENCON
  • LUÍS PEDRO VIEGAS
  • MAICON PIERRE LOURENÇO
  • Data: Aug 5, 2020
  • View Dissertation/Thesis  

  • Show Abstract
  • Given the necessity for new catalysts for the production of hydrogen gas from the water splitting reaction (an alternative to fossil fuels), the interactions between aluminum and silicon nanoclusters with water have been studied in this work. These two elements already have applications in electronics and Al has known catalytic activity. When these two are mixed in the atomic scale, their properties become different from pure elements. For this reason, water adsorption (one of the main existing hydrogen sources) to the Al8, Si8, Al4Si4, Al2Si6, Al13, Si13, Al12Si e Al2Si11 nanoclusters has been investigated. Calculations at the MP2 level were performed with the GAMESS computational package using cc-pVDZ basis set for obtain the energies and vibrational frequencies.

    Of the clusters evaluated, the alloys formed by both aluminum and silicon had higher adsorption energies than those of pure clusters. The best results were obtained for clusters of eight atoms, with three of the four structures evaluated presenting energies above 0,500eV. The only thirteen atoms cluster that presented energy in this range was Al2Si11. It has also been noticed that the adsorption was more effective in alloys with low aluminum contented, and the two highest adsorption energies were 0,648eV and 0,610eV, corresponding to the Al2Si11 and Al2Si6 clusters respectively. It has been shown that the interaction of water with pure silicon clusters is weak, with adsorption energies below 0,400eV. At simulated infra red spectrum, it is possible to notice the increase in intensity and the red shift of the peaks due to the interaction with water, a particularly pronounced effect for clusters with higher adsorption energies.

8
  • NATÁLIA CRISTINA FERNANDES MACHADO
  • Synthesis and characterization of the Fe/activated carbon composite from polystyrene foams: a new magnetic adsorbent for the removal of organic contaminants

     

  • Advisor : PAULO FERNANDO RIBEIRO ORTEGA
  • COMMITTEE MEMBERS :
  • PAULO FERNANDO RIBEIRO ORTEGA
  • PRISCILA PEREIRA SILVA CALDEIRA
  • PATTERSON PATRICIO DE SOUZA
  • JOAO PAULO CAMPOS TRIGUEIRO
  • Data: Aug 10, 2020
  • View Dissertation/Thesis  

  • Show Abstract
  • Recently, activated carbons (CAs) derivated from plastic waste have been highlighted
    in the removal of contaminants due to their excellent textural properties and high adsorption
    capacity for organic contaminants. Obtaining CAs with magnetic properties makes them even
    more attractive, due to the technical easiness to its removing from the bulk of aqueous
    solutions. In this sense, two CAs, magnetic (CAM) and a non-magnetic (CA), are synthesized
    from expanded polystyrene (EPS) residues. Both are prepared through of carbonization of
    EPS dissolved in ethyl acetate (containing iron (III) tris(acetylacetonate) for magnetic), with
    chemical activation by KOH at 800 ºC. This work reports for the first time the direct synthesis
    of a magnetic activated carbon composite derivated from PS.
    The materials are characterized by N
    2 adsorption/desorption, X-ray diffraction,
    thermogravimetry, scanning electron microscopy (SEM), Mössbauer spectroscopy and zeta
    potential. The iron phases present in the CAM are: Fe
    0, Fe3C and Fe3O4; being the last one
    responsible for the material's magnetism. The high specific surface areas and the total volume
    of CAM pores are highlighted and are equal to 672.41 m
    2/g and 0.345 cm3/g, respectively.
    Despite of the lower values of these textural properties in relation to CA, these are still situated
    among the highest valeus found in the literature of magnetic composites.
    Considering the application of CAs, the materials are evaluated in the removal of the
    following contaminants: methylene blue (AM), indigo carmine (IC) and hydroxybenzene
    (FE). For CAM, the maximum adsorbed amounts of AM, IC and FE correspond to 275, 536
    and 116 mg/g in the optimal pH. In the optimal pH and at 25 °C, the kinetics and adsorption
    isotherms are studied and the thermodynamic properties are calculated by a model from
    statistical mechanics. Finally, the capacity of regeneration of the CAs as adsorbents is
    available in 5 cycles, with emphasis on CAM that retain 60% of its removal capacity, while
    CA is able to retain only 20%


9
  • GABRIELA SANTOS CALDEIRA
  • Análise de BTEX em águas subterrâneas por dispositivo de captura IT-FEX: Influência da espessura da fase  polimérica.

  • Advisor : PATTERSON PATRICIO DE SOUZA
  • COMMITTEE MEMBERS :
  • PATTERSON PATRICIO DE SOUZA
  • ILDEFONSO BINATTI
  • ADRIANA AKEMI OKUMA
  • ANA MARIA DE RESENDE MACHADO
  • Data: Aug 26, 2020
  • View Dissertation/Thesis  

  • Show Abstract
  • A contaminação do solo por combustíveis tem tomado atenção de pesquisadores devido à ocorrência dos acidentes envolvendo este tipo de poluente e persistência das espécies orgânicas liberadas.O benzeno, tolueno, etilbenzeno e xilenos (BTEX), compostos indicadores de contaminação por combustíveis, podem contaminar o solo por vazamento dos tanques de armazenamento (subterrâneos ou acima do solo) de combustível e por derramamentos acidentais. A utilização de métodos analíticos para quantificação/identificação de BTEX é limitada pela complexidade de amostragem/preparação de amostras e equipamentos. Métodos baseados em micro-extração por fase sólida (SPME) representam uma alternativa mais simples, mas requerem procedimentos de calibração complexos, além de alto custo e fragilidade. Após o desenvolvimento da metodologia de análise do sistema de captura, realizado em trabalhos anteriores do mesmo grupo, um próximo passo importante é controle da metodologia de confecção dos compostos. Esta metodologia de preparo dos dispositivos de captura deve ser reprodutível e com o devido estabelecimento da relação “espessura de fase polimérica/grupo de compostos analisados”. O objetivo desta pesquisa foi desenvolver um método simples para quantificação de BTEX em amostras de água subterrâneas utilizando o GC-MS e verificar a influência da espessura da fase polimérica na análise de BTEX em água.A fase polimérica depositada foi estudada por Análise Termogravimétrica (TG) e Espectroscopia de Absorção na região do Infravermelho (IR) e a performance analítica testada para amostras de água adicionadas de BTEX no equipamento de GC-MS. Verificou-se por TG que para a deposição de membranas poliméricas de PDMS é necessário um tratamento térmico de 290 °C antes da utilização para eliminar contaminação por tolueno ou de monômeros residuais. Na caracterização do PDMS por IR, verificou-se a presença de bandas características do polímero, indicativo que o processo de deposição da fase não alterou a estrutura química do polímero. Verificou-se que nenhum dos dispositivos contendo espessuras diferentes apresentou efeito memória dos analitos BTEX, ou seja, a primeira dessorção no equipamento já foi suficiente para completa retirada dos analitos da fase de captura PDMS. Os coeficientes de variação tanto para repetibilidade tanto para reprodutibilidade foram abaixo de 12%. O método foi aplicado com sucesso para análise das amostras dos testes de solubilidade em água subterrânea, sendo que, em todos os tempos analisados as concentrações de BTEX atingiram concentrações acima do limite estipulado pela portaria Portaria 2914/2011. Os limites de detecção do método para os compostos de benzeno, tolueno, etilbenzeno, p-xileno e o-xileno foram de 0,43; 0,33; 0,14 µg L-1, 8,78 e 12,73 ng L-1, respectivamentee de quantificação foram de 0,53; 0,40; 0,17 µg L-1, 10,73 e 15,54 ng L-1, respectivamente.

2019
Dissertations
1
  • ITALO ROCHA COURA
  • Evaluation of the Composite Processing Based on High Density Polyethylene and Iron Mining Reject

  • Advisor : PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • COMMITTEE MEMBERS :
  • PATRICIA SANTIAGO DE OLIVEIRA PATRICIO
  • PAULO FERNANDO RIBEIRO ORTEGA
  • Ana Pachéli Héitmann Rodrigues
  • Data: Feb 12, 2019
  • View Dissertation/Thesis  

  • Show Abstract
  • In order to evaluate modifications promoted by different processing methodologies, four composite
    materials based on High Density Polyethylene (HDPE) and iron ore tailings were produced in the same
    filler/matrix contents. The materials were studied by thermal, mechanical and morphological analysis.
    The presence of the reject in the polymer matrix promoted an increase in mechanical resistance in all
    materials produced. The modifications promoted by the addition of the fillers were more intense in the
    materials prepared using the mixer, presenting better dispersion of the filler in the matrix, as shown by
    the results of FTIR and SEM. The extruder was less efficient in the produced materials, due to the
    significant partial loss of the waste during processing.

2
  • Fernanda Gabriela Gomes Pereira
  • DEVELOPMENT OF NEW MATERIALS BASED ON HYDROXYAPATITE AND STEEL POWDER FOR USE IN ENVIRONMENTAL DECONTAMINATION PROCESSES

  • Advisor : RAQUEL VIEIRA MAMBRINI
  • COMMITTEE MEMBERS :
  • RAQUEL VIEIRA MAMBRINI
  • EUDES LORENCON
  • DIANA QUINTAO LIMA
  • Data: Feb 28, 2019
  • View Dissertation/Thesis  

  • Show Abstract
  • In this work were developed two series of materials, activated coals and catalysts. These materials were based on industrial waste: hydroxyapatite from bone and steelmaking dust from Foundry steel industry. 

    For the synthesis of activated coals, hydroxyapatite was subjected to physical activation the 600 ° C and 700 ° C using the agents ativantes carbon dioxide and ethanol, in order to increase your surface area to enhance your adsorbent effect. The activated coals were characterized by thermogravimetric analysis (TG), adsorption and desorption isotherms of N2, scanning electron microscopy (SEM), x-ray diffraction (XRD), and absorption spectroscopy in the infrared region (IV). The activated coals were applied on adsorption of contaminants.  

    The synthesis of hydroxyapatite catalysts were impregnated with steelmaking dust (PA), steel industry waste, in concentrations of 5 and 15% m/m and impregnated materials were submitted to chemical vapor deposition process (Chemical Vapor Deposition-CVD) to 700 º C using ethanol as carbon source. The CVD process aims at the reduction of iron and training phases of carbonáceas structures on the inert martiz hydroxyapatite. As the materials feature nonpolar hydrophobic properties (carbon) and polar hydrophilic properties (hydroxyapatite and PA), they are referred to as hybrids. The materials were characterized by thermogravimetric analysis (TG), x-ray diffraction (XRD), adsorption and desorption isotherms of N2, scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS) and X of spectroscopy absorption in the infrared (IR). For the application of the synthesized catalyst, oxidation tests were performed on contaminants in wastewater from oil and textiles.

    There's a great relevance in the transformation of waste used in this work, such as bone and steelmaking dust, technological materials as catalysts for the removal of environmental contaminants because currently there are a few articles in the literature that use steel powder for this purpose, since it is generated on a large scale and has high content of metal oxides.

3
  • Gabriel Dias dos Reis
  • Development of prototype for static sampling and preconcentration of organic
    compounds in aqueous solution


  • Advisor : PATTERSON PATRICIO DE SOUZA
  • COMMITTEE MEMBERS :
  • PATTERSON PATRICIO DE SOUZA
  • RAQUEL VIEIRA MAMBRINI
  • ANA MARIA DE RESENDE MACHADO
  • Data: Apr 30, 2019
  • View Dissertation/Thesis  

  • Show Abstract
  • The extraction and preconcentration of organic compounds microtechnologies that
    are employed to prepare samples for gas chromatography (GC) are of fundamental
    importance because they allow the analysis of compounds at low concentrations and in
    matrices that have not been directly injected in the equipment. One of the main preparation
    techniques is Solid Phase Microextraction or SPME, which consists of the extraction of
    analytes in selective polymer coatings with subsequent desorption in the gas chromatograph.
    Among the variations in SPME techniques, the configuration IT-SPME (Microextraction in
    Solid Phase in Tube) is a promising, since its configuration is compatible with most
    chromatographic injectors, and accessory equipment for the injection is not necessary. In the
    present work, a glass tubular prototype open and straight was developed, coated with a
    polymer phase of PDMS (polydimethylsiloxane). The polymer phase was characterized
    chemically by Infrared Spectroscopy and Thermogravimetry. The coating used had a
    thickness of 80 μm and thermal stability at 400 °C. Phenol and Dodecanol aqueous solutions
    were used as a model at concentrations from 50 ppb to 50 ppm. The extracted analytes were
    identified and quantified in GC-MS by different modes of injection, pressure, temperature
    and gaseous flow of the injector, and modes of acquisition in the mass spectrometer. The
    results obtained show repeatability, reproducibility, absorption curves and calibration. The
    detection and quantification limits found for the dodecanol with the prototype were 2.30 ng
    L
    -1 and 13.10 ng L-1, respectively. The performance parameters evaluated indicated
    suitability of the validated method. In this way, the developed device presents itself as an
    important market innovation with high commercial potential


4
  • Mateus Augusto Martins de Paiva
  • Ab initio study on the formation and destruction of the SiS molecule and its astrochemical relevance

  • Advisor : BRENO RODRIGUES LAMAGHERE GALVAO
  • COMMITTEE MEMBERS :
  • BRENO RODRIGUES LAMAGHERE GALVAO
  • LUIS ARGEL POVEDA CALVINO
  • MATEUS XAVIER SILVA
  • VINICIUS CÂNDIDO MOTA
  • Data: Aug 5, 2019
  • View Dissertation/Thesis  

  • Show Abstract
  • Astrochemistry is still an interdisciplinary vanguard science. The means and framework for its
    development did not appear until the late twentieth century. For this reason, there are still many open
    problems to be solved and studied. Astrochemistry has as main objective to study the chemistry of the
    cosmic environment, proposing reaction mechanism and explanations for the formation of certain
    molecules, experimentally or not.


    Several astronomers have already made observations of the isolated OSi and SiS
    molecules in certain space regions, but no observations have been made for the OSiS
    molecule, even though there is evidence that it is a link between OSi and SiS. The OSi
    molecule has already been well studied and its origin of formation is well understood.
    However the SiS received less attention and its formation in the interstellar environment is
    still subject of debate.


    The aim of this work is to propose a possible reaction path for the relationship of these
    molecules, through ab initio calculations. By studying the potential energy surface of the OSiS
    molecule, it has been discovered that the SiS molecule is easily converted to OSi, in
    collisions with oxygen, but the conversion of OSi to SiS does not occur. It has also been
    found that the reaction of OSi + S leads to the formation of the stable molecule OSiS in its
    singlet state through a crossing region of singlet and triplet states, in addition it is envisaged
    that other isomers can also be formed by this route, such as cyclic OSiS and SOSi.


    It has been found that the SiS molecule can be formed by reactions between atomic
    silicon with hydrosulphide molecule (HS) and hydrogen sulfide (H 2 S). In the reaction with HS
    the SiS molecule is easily formed, but with H 2 S the reaction happens with exchange of
    spin states. Both reactions are exothermic. The reaction paths for several other molecules
    and isomers that are related to silicon, sulfur and hydrogen has also been proposed.

     

     

5
  • NATHÁLIA RODRIGUES DE OLIVEIRA
  • Synthesis and characterization of MOFs based on terephthalic acid by PET used in the removal of petroleum contaminants

  • Advisor : RAQUEL VIEIRA MAMBRINI
  • COMMITTEE MEMBERS :
  • RAQUEL VIEIRA MAMBRINI
  • EUDES LORENCON
  • LEONEL DA SILVA TEIXEIRA
  • Data: Aug 30, 2019
  • View Dissertation/Thesis  

  • Show Abstract
  • Petroleum is a complex combination of hydrocarbons, it can also contain small amounts of nitrogen, oxygen, sulfur compounds, and metal ions. Oxygen, nitrogen, and sulfur compounds are contaminants and cause a few drawbacks during oil processing and the end use of its derivatives. In 1995, the term metal-organic framework - MOF emerged in the literature, bringing excellent properties to be used. In order to synthesize, characterize and apply catalysts used to remove petroleum contaminants, this work can cause damage to terephthalic acid (TA) from the basic hydrolysis of poly-terephthalic ethylene - PET, raw material used in domestic waste. The TA obtained and commercial (Aldrich®) were characterized by infrared spectroscopy and thermogravimetric analysis to ensure that the hydrolysis was satisfactory. Next, four catalysts were synthesized using TA obtained by PET (MOF-Nb/ATobtained and MOF-Fe/ATobtained) and using commercial TA (MOF-Nb/AT and MOF-Fe/AT). These were characterized and subsequently applied in oxidation in the removal of methylene blue, dibenzothiophene and quinoline, using hydrogen peroxide as oxidant. The synthesized catalysts obtain very expressive removal percentages for methylene blue, dibenzothiophene, and quinoline. When comparing the percentage of catalyst removal synthesized in this work with other published works, it can be said that MOF-Nb and MOF-Fe have excellent catalytic capacity applied to the removal of sulfur compounds, nitrogenous and contaminants used in aqueous medium.

2018
Dissertations
1
  • Alexandre Bizzotto de Carvalho
  • Biological, Structural, Magnetic, and Electronic Properties of a Novel Copper(II) Coordination Polymer containing Nalidixic Acid and 8-Hydroxyquinoline.

  • Advisor : PRISCILA PEREIRA SILVA CALDEIRA
  • COMMITTEE MEMBERS :
  • PRISCILA PEREIRA SILVA CALDEIRA
  • WALACE DOTI DO PIM
  • FLÁVIA CRISTINA SILVA DE PAULA
  • Data: Aug 8, 2018
  • View Dissertation/Thesis  

  • Show Abstract
  • The neoplasia is a pathology that affects millions of people throughout the world. The design, preparation and studies of the pharmacology of metallic complexes have been widely explored for cancer treatment. Among the promising antineoplastic agents,the copper-containing compounds have been drawn attention. This work describes the synthesis, structural characterization, physical properties, spectroscopic studies, and antitumoral activity of a novel copper(II) complex with biological relevant ligands. The chosen ligands, 8-hidroxyquinolone and nalidixic acid, belong the quinoline class. The monocrystal X ray diffraction analisys demonstrated that the compound structure is a polymer that exhibits a square base pyramidal geometry. The nalidixic acid and 8-hidroxyquinoline behave as bidentate deprotonaded ligands binding to copper (II) ion in equatorial positions, while the axial position is composed by an anti-anti carboxylate bridge from nalidixic acid . This structural feature is unique for compounds containing nalidixic acid. In solution, the prepared compound exists as a neutral mononuclear species. By DNA interaction studies the compound has demonstrated that could by to DNA by groove binding mode. The antitumoral activity of the prepared compound has been investigated in k562 tumor cell line. The compound presented cytotoxic activity higher than those obtained for free ligands

2
  • Ana Débora Porto Silveira
  • Aluminium and Silicon Nanoalloys: structure and stability

  • Advisor : BRENO RODRIGUES LAMAGHERE GALVAO
  • COMMITTEE MEMBERS :
  • EMERSON FERNANDES PEDROSO
  • BRENO RODRIGUES LAMAGHERE GALVAO
  • MARCIO MELQUIADES SILVA
  • LUIS ARGEL POVEDA CALVINO
  • Data: Aug 14, 2018

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  • In this work the structures of AlSi nanoligas with sizes between 3 and 13 atoms were studied in order to predict their geometries and to calculate the properties related to their stability and reactivity. For this, theoretical structure electronic calculations were used. The methodology used to find the structures with the lowest energy was the search for homotops and the genetic algorithm, both using MP2 as computational. By means of these calculations, it was possible to prove the results obtained by experimental studies with clusters of 13 atoms, where the Al12Si composition is one of the most stable alloys. In addition, some properties of the agglomerates can be calculated, such as binding energy, excess energy and HOMO-LUMO gap, where it is possible to predict which are the most stable, reactive and inert compositions. It has also been possible to predict some agglomerates that are more likely to be obtained experimentally, such as, Al4Si2, Al4Si4, Al2Si6, Al6Si3, Al4Si7, Al8Si4, Al2Si11 e Al12Si.

3
  • Raquel Patrícia Rungue Alvim
  • SYNTHESIS AND CHARACTERIZATION OF MOLYBDEN DOPED GRAPHITIC CARBON NITRIDE AND ITS APPLICATION AS  CATALYST IN OXIDATION REACTIONS

  • Advisor : EUDES LORENCON
  • COMMITTEE MEMBERS :
  • EUDES LORENCON
  • RAQUEL VIEIRA MAMBRINI
  • DIANA QUINTAO LIMA
  • Data: Nov 22, 2018
  • View Dissertation/Thesis  

  • Show Abstract

  • In this work the graphite carbon nitride doped with molybdenum (Mo/g-C3N4) was synthetized by simple calcination. The morphology, structure and chemical composition of the catalyst were characterized, proving the presence of highly dispersed molybdenum species stabilized by the nitrogen atoms of g-C3N4. This material was applied in the oxidation of various substrates with hydrogen peroxide or tert-butyl hydroperoxide (TBHP) as oxidant. The results showed that the Mo (VI) sites stabilized on the heptazine ring of the support can interact with H2Oor TBPH forming peroxo-Mo (VI) active groups for oxidation. 
    The catalyst showed high catalytic activity in the non-selective oxidation of methylene blue (MB) when compared to MoOor pure g-C3N4. In addition, it also showed high conversion and selectivity in the oxidation of sulphides to sulfoxides, oxidation of nitrogen compounds to N-oxides under mild reaction conditions (room temperature and low H2Oconcentration), and potential application in epoxidation of olefins. The results showed that the activity of Mo/g-C3Ndecreased successively during reuse in MB oxidation, but remained practically unchanged in the selective oxidation of MPS, after five cycles of reuse.
    Lastly, the catalytic performance of the Mo/g-C3Nwas evaluated in the removal of sulfur compound in simulated petroleum matrix (DBT in cyclohexane) by oxidative desulphurization (ODS). The results demonstrated that the increase of catalyst concentration and temperature can contributed to improve the efficiency of the reaction, while the excess H2Oleads to a deactivation of the catalyst by leaching of the active molybdenum species form  its structure. Kinetic studies revealed that the reaction presents a pseudo first order kinetics with respect to DBT and catalyst, negative order to H2Oand activation energy of 43.6 kJ mol-1. The catalyst showed good activity during the two cycles of reuse, reducing to 60 % in the third use, owing to the leaching of the active species of Mo of the g-C3Nstructure.

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