RAFAEL HENRIQUE LAZZARI GARCIA

RAFAEL HENRIQUE LAZZARI GARCIA

(Fonte: Lattes)

Abstract

Ao se formar no Colégio Bandeirantes, em 1998, realizou parte do curso de graduação em Ciências Sociais pela USP (2000 e 2001) e graduou-se em Ciências Com Habilitação Em Química nas Faculdades Oswaldo Cruz (2000 a 2003). Desempenhou parte da iniciação científica no IPEN em 2001, na área de Química Ambiental, e foi bolsista no agrupamento de processos químicos do IPT, de 2001 a 2004, aonde trabalhou com cristalização e caracterização de matérias primas industriais. Obteve o grau de Mestre, em 2007, no Instituto de Pesquisas Energéticas e Nucleares, na Universidade de São Paulo, estudando cerâmicas para células a combustível SOFC, e o grau de Doutor, em 2019, na área de caracterização de combustíveis nucleares. Em 2007, realizou visitas técnicas a centros de pesquisas no Japão, como parte do programa de Intercâmbio de Grupos de Estudo, patrocinado pela Fundação Rotária. De 2008 a 2010 foi professor voluntário no curso de alfabetização de adultos promovido pelo Rotary Liberdade. Atualmente é pesquisador do Instituto de Pesquisas Energéticas e Nucleares, no Centro de Combustíveis Nucleares, responsável pelos laboratórios de fluorescência e difração de raios X, e estuda combustíveis para reatores do tipo MTR. (Texto extraído do Currículo Lattes em 4 maio 2023)

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Solid-liquid equilibrium of paracetamol in water-ethanol and water-propylene glycol mixtures
2021 - ASSIS, GABRIEL P.; GARCIA, RAFAEL H.L.; DERENZO, SILAS; BERNARDO, ANDRE
Solubility is one of most important property to produce active pharmaceutical ingredients (APIs), beyond of being related to its bioavailability. In this context, itwas determined paracetamol solid-liquid equilibriumin temperatures from20 to 50 °C for two solvent systems:water - ethanol andwater - propylene glycol (PG), by refractometry method. The experimental results were compared with five thermodynamic models (Apelblat,Wilson, UNIQUAC, NRTL and λh) and data from the literature, showing good correlations for Apelblat and the best predictive fit for the NRTL model in both solvent mixtures. Maximum solubility values were observed in a 75% ethanol composition, this result being unusual and not the same with PG. the results of this work were compared with the literature and some references point to similar behavior. Optical microscopy and X-ray diffractionmeasurements of the solids in equilibrium with the liquid indicate that maximum solubility is not associated with a change in the crystalline structure of the solid
Adsorção líquida no siliceto de urânio
2019 - OLIVEIRA, VITORIA A.; CARVALHO, ELITA U.; DURAZZO, MICHELANGELO; SAKATA, SOLANGE K.; GARCIA, RAFAEL H.L.
O siliceto de urânio é um intermetálico usado como combustível nuclear na maioria dos reatores de pesquisa modernos, incluindo os reatores MB-01 e IEA-R1 do IPEN. Durante a produção, o material é submetido a um rigoroso controle de qualidade, que inclui análises de tamanho de partícula, densidade, caracterização e composição da fase cristalina. A quantificação das fases cristalinas presentes é realizada por difração de raios X (DRX) e refinamento dos dados usando o método Rietveld. No entanto, devido à alta absorção de raios X por esse material, no que diz respeito ao método de quantificação adotado, é muito importante reduzir o tamanho das partículas. Para este objetivo, um moinho vibratório dedicado é usado antes da análise de DRX, reduzindo o diâmetro médio das partículas para poucos micrômetros. Para evitar a oxidação das amostras, o processo de moagem ocorre em meio isopropanóico, o qual é seco posteriormente, em vácuo a 80 ºC. Porém, em muitos casos, verifica-se que as massas das amostras moídas são maiores do que as iniciais. Nesse sentido, esse trabalho propõe analisar a causa dessa diferença de massa. Granulometria a laser, termogravimetria (TG). Os resultados de TG sugerem que uma camada é fortemente adsorvida ao material, protegendo o pó de oxidação em temperaturas acima de 4000C.
XRD characterization thermoplastic STARCH/poly (butylene adipate-co-terephthalate) (TPS/PBAT) blends irradiated by gamma rays
2019 - CASTRO, DIONE P. de; GARCIA, RAFAEL H.L.; SILVA, LEONARDO G. de A. e
The aim of this research was to check the changes in the structure and crystallinity of non-irradiated and irradiated thermoplastic starch blends (TPS)/poly (butylene adipate-co-terephthalate) - PBAT and also to evaluate the behavior of castor oil in place of glycerol. In this work, the characterization was performed by X-ray diffraction (XRD), in which the crystallinity index (IC) of non-irradiated and irradiated blends of TPS/PBAT was calculated. For plastification of the TPS, glycerol, castor oil and TWEEN® 80 were used to verify the compatibility and compare the blends with each other. The samples were prepared by extrusion and irradiated at 25 kGy with gamma rays from a 60Co source. However, the crystallinity indexes of the blends were altered according to the plasticizer used and the use of TWEEN® 80. Thus, it been concluded that glycerol substitution by castor oil is feasible in TPS/PBAT blends.
Synthesis of reduced graphene oxide by gamma irradiation
2019 - JACOVONE, RAYNARA M.S.; TOMINAGA, FLAVIO K.; BRANDAO, OCTAVIO A.B.; GARCIA, RAFAEL H.L.; SAKATA, SOLANGE K.
Graphene is a 2D carbon-based nanomaterial that has a high specific surface area with remarkable physical and chemical properties. These unique properties make graphene a nanomaterial with wide electrochemical applications. However, it is not possible to functionalize graphene sheets and increase their field of application because there are no organic functions in their surface. So, an important precursor of graphene, graphene oxide (GO), then contains oxygen functional groups on the surface is been using functionalized. Partial reduction of graphene oxide leads to reduced graphene, a nanomaterial that combines both properties of graphene and graphene oxide: an excellent electrical and thermal conductivity and remaining oxygen groups that allow its functionalization. In the literature it is described many ways to produce reduced oxide graphene from graphene oxide, such as chemical reduction using hydrazine hydrate or NaBH4 or thermal reduction using high temperatures. Here in it is described an attractive and green process to reduce graphene oxide in aqua solution using gamma radiation. Exfoliated graphene oxide (1-100mg / L) under inert medium was submitted to gamma radiation. The radiation dose ranged from 20 to 80 kGy and the product was centrifuged. The characterization was performed by X-Ray Diffraction (XRD), Infrared Spectroscopy (ATR-FTIR) and Thermogravimetric analysis (TGA). The XRD results demonstrated characteristic diffraction peaks at about 10° and 25° corresponding to GO and Graphene, respectively, indicating the rGO formation. ATR-FTIR showed the characteristic peaks of functional groups (epoxy, hydroxyl and carboxyl) for GO. After the gamma irradiation, it was noticed a reduction at the intensity of the peaks at of carboxyl/carbonyl an increase at aromatic carbon bond. TGA analysis indicated a decrease of the oxygen groups.
Chemical and physical analysis of sandstone rock from Botucatu formation
2019 - CORREA, JOAO C.; GARCIA, RAFAEL H.L.; SANTOS, RODRIGO S. dos; AMADEU, RAFAEL A.; BERNARDES, THIAGO L.S.; VELO, ALEXANDRE F.; CARVALHO, DIEGO V. de S.; NASCIMENTO, TARCIANO J. do; CAVALLARO, FRANCISCO A.; MESQUITA, CARLOS H. de; HAMADA, MARGARIDA M.
The productive capacity of the Guarani Aquifer System is subject to variations along its length, due to its complex structural and compositional heterogeneity. Several parameters may influence the quality of this reservoir rock, such as its mineralogical and textural constitution, as well as the physicochemical processes, its diagenesis is not the same throughout the aquifer, influencing the water productivity in wells in different locations. Such parameters are useful in the geoscience studies, in the elaboration of diagenetic models for the prediction of the reservoir quality. In this work, several properties of the sandstone rock from Botucatu Formation were determined, using different techniques, such as geotechnical tests, optical microscopy (MO), electron scanning microscopy (SEM), X-ray Fluorescence and X-ray diffraction. The results indicate that the studied sandstones have characteristics of the reservoir rocks, with potential for water storage.
Performance of the X-ray powder diffraction (XRD), X-ray fluorescence (XRF) and the industrial computed tomography used for characterization of the vesicular volcanic rock
2019 - SANTOS, RODRIGO S. dos; CAVALLARO, FRANCISCO DE A.; BERNARDES, THIAGO L.S.; AMADEU, RAFAEL A.; GARCIA, RAFAEL H.L.; VELO, ALEXANDRE F.; CARVALHO, DIEGO V. de S.; MESQUITA, CARLOS H. de; HAMADA, MARGARIDA M.
Volcanic rock is a designation in geology given to extrusive igneous rocks. One type of igneous rock of interest, in economic terms, is the vesicular, since besides the knowledge of the morphology (positioning, size, direction and interconnectivity of the vesicles) of these structures within the spill, there is also an economic interest regarding the possibility of this rock as a reservoir of fluids (water and hydrocarbons). In this work, samples of vesicular volcanic rock from the Paraná Basin were studied for their characterization, aiming to contribute in the knowledge of this rock proprieties as a reservoir of fluids. The elements present inside the rocks were identified and quantified by X-ray fluorescence and X-ray diffraction. The dimensions of the vesicles and the interconnection between them could be clearly observed in the reconstructed images of the rocks measured, using the third generation gamma ray industrial tomography.
Characterization of the petrology of the tar sandtone rock of the Paraná basin
2019 - AMADEU, RAFAEL A.; BERNARDES, THIAGO L.S.; SANTOS, RODRIGO S. dos; GARCIA, RAFAEL H.L.; VELO, ALEXANDRE F.; CARVALHO, DIEGO V. de S.; CAVALLARO, FRANCISCO A.; MESQUITA, CARLOS H. de; HAMADA, MARGARIDA M.
In the state of São Paulo (Brazil), occurrences of tar sandstone are known in Botucatu, Angatuba, Pirambóia, Anhembi and Bofete municipalities. In the present work, a sample of white tar sandstone was taken from Anhembi municipality, located at Km 168 of the Castelo Branco Highway. In the petroleum area, sandstones act as excellent hydrocarbon reservoirs, since they have specific characteristics, such as: high porosity and permeability. Porosity is a property of rocks, and it may be understood as the voids contained in the matrix (where fluids remain stored), while permeability is the ability of the rock to transmit these stored fluids. Due to these characteristics of sandstones, researchers have shown a growing interest in the study and characterization of this type of rock, which is a fundamental element of an oil system. In the present work, four characterization techniques were used in the Anhembi tar sandstone sample, namely: X-ray Diffraction, X-ray Fluorescence, Scanning Electron Microscope and the third generation Industrial Computerized Tomography. Through these techniques, the chemical composition, grain morphology, crystalline structure phases and an image of a slice of the internal structure of the white tar sandstone sample were obtained.
Study of the petrology of the shale rock from the Parana basin
2019 - BERNARDES, THIAGO L.S.; AMADEU, RAFAEL A.; SANTOS, RODRIGO S. dos; GARCIA, RAFAEL H.L.; VELO, ALEXANDRE F.; CARVALHO, DIEGO V. de S.; CAVALLARO, FRANCISCO A.; MESQUITA, CARLOS H. de; HAMADA, MARGARIDA M.
In the present work, the characteristics of shale rock, collected in the surrounds of Limeira, in the interior of São Paulo, were studied. Shales are rocks formed by the consolidation of layers of clay, silt or mud, and are composed of minerals derived from mechanical abrasion materials, weathering final product and chemical and/or biochemical additions [1]. Shales are mostly fine granules, susceptible to the mineralogical rearrangement, and their chemical composition is quite varied due to the geomorphology and the tectonism undergone by the sedimentary basins. They are impermeable structures, formed by the consolidation of layered clay with thin laminations. Because of these characteristics presented, together with the decline of petroleum production, a growing interest in the better understanding and knowledge of the physical-chemical properties of the interior of shale rocks has been demonstrated. In this work, different methodologies were used to characterize them, using the Gamma Ray Computed Industrial Tomography technique along with other complementary procedures, such as Scanning Electron Microscopy (SEM), X-Ray Fluorescence and X-Ray Diffraction. Several characteristics have been studied, such as the analysis of the particle morphology, the contrasts and distributions of these particles in the internal structure of the rock, identification of the types of elements present (quantitative analysis), as well as establishing a proportion in which each element is present in the mineral through its crystalline structure and obtaining images of the rock internal structure.
Comparison of gamma radiation effects on natural corn and potato starches and modified cassava starch
2018 - TEIXEIRA, BRUNA S.; GARCIA, RAFAEL H.L.; TAKINAMI, PATRICIA Y.I.; DEL MASTRO, NELIDA L.
The objective of this work was to evaluate the effect of irradiation treatment on physicochemical properties of three natural polymers, i.e. native potato and corn starches and a typical Brazilian product, cassava starch modified through fermentation-sour cassava- and also to prepare composite hydrocolloid films based on them. Starches were irradiated in a Co-60 irradiation chamber in doses up to 15 kGy, dose rate about 1 kGy/h. Differences were found in granule size distribution upon irradiation, mainly for corn and cassava starch but radiation did not cause significant changes in granule morphology. The viscosity of the potato, corn and cassava starches hydrogels decreased as a function of absorbed dose. Comparing non-irradiated and irradiated starches, changes in the Fourier transform infrared (FTIR) spectra in the 2000-1500 cm(-1) region for potato and corn starches were observed but not for the cassava starch. Maximum rupture force of the starch-based films was affected differently for each starch type; color analysis showed that doses of 15 kGy promoted a slight rise in the parameter b* (yellow color) while the parameter L* (lightness) was not significantly affected; X-ray diffraction patterns remained almost unchanged by irradiation.
Analysis of slag formation during UF4 magnesiothermic reduction
2017 - DURAZZO, MICHELANGELO; SALIBA-SILVA, ADONIS M.; GARCIA, RAFAEL H.L.; CARVALHO, ELITA F.U. de; RIELLA, HUMBERTO G.
Metallic uranium is a fundamental raw material for producing nuclear fuel elements for research reactors and irradiation targets for producing 99Mo, as U3Si2, UMo alloy, UAlx, and uranium thin foils. Magnesiothermic reduction of UF4 is a possible route in the nuclear fuel cycle for producing uranium as a metal ingot. The main concern about the reducing scale to produce low-enriched (metallic) uranium (LEU) (around 1 kg) is the relatively low yield compared to calciothermic reduction. Nevertheless, the magnesiothermic reduction has the advantages of having lower cost and being a safer method for dealing with uranium processing. The magnesiothermic process, as a batch, is closed inside a sealed crucible. In the present study, in order to have a qualitative idea of the kinetics during the ignition moment, the slag projected over the lateral inner face of the crucible was used to sketch the general magnesiothermic evolution. The methods used were metallographic observation and X-ray diffraction followed by Rietveld refinement. The results of these analyses led to the conception of a general reaction development during the short time between the ignition of the reducing reaction and final settlement of the products. Relevant information from this study led to the conclusion that uranium is not primarily present in the lateral slag projection over the crucible during the reaction, and the temperature level may reach 1500°C or more, after the ignition.