CARLOS HENRIQUE DE MESQUITA

CARLOS HENRIQUE DE MESQUITA

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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
2021 - SANTOS, R.S.; CAVALLARO, F.A.; BERNARDES, T.L.S.; AMADEU, R.A.; GARCIA, R.H.L.; VELO, A.F.; MESQUITA, C.H.; HAMADA, M.M.
Volcanic rock is a designation in geology given to extrusive igneous rocks. One type of igneous rock of interest, in economic terms, is 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 to 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 by the third generation Gamma ray industrial tomography technique
Petrological study of the Iraty Formation Shale Rocks from Paraná Basin, Limeira, São Paulo
2021 - BERNARDES, T.L.S.; AMADEU, R.A.; SANTOS, R.S.; GARCIA, R.H.L.; VELO, A.F.; CAVALLARO, F.A.; MESQUITA, C.H.; HAMADA, M.M.
Shales are fine-grained rocks formed by clays and silt-sized particles in thin, relatively impermeable layers. They are originated from rocks that suffered weathering and erosion and their composition is quite variable. When oil production declines, interest arises to improve the understanding of the physicochemical properties of unconventional rocks, like shale. For the characterization of the shale samples of the Iraty Formation, the gamma-ray computed industrial tomography technique has been proposed to be used as an alternative to obtaining information about each element present in the mineral, the pore distribution, through the shale morphology. The tomographic results were compared with those obtained by conventional methodologies used in the petrological analysis, such as scanning electron microscopy (SEM), x-ray fluorescence, and x-ray diffraction.
Influence of impurities on the radiation response of the TlBr semiconductor crystal
2017 - SANTOS, ROBINSON A. dos; MESQUITA, CARLOS H. de; SILVA, JULIO B.R. da; FERRAZ, CAUE de M.; COSTA, FABIO E. da; MARTINS, JOAO F.T.; GENNARI, ROSELI F.; HAMADA, MARGARIDA M.
Two commercially available TlBr salts were used as the rawmaterial for crystal growths to be used as radiation detectors. Previously, TlBr salts were purified once, twice, and three times by the repeated Bridgmanmethod. Thepurification efficiency was evaluated by inductively coupled plasma mass spectroscopy (ICP-MS), after each purification process. A compartmental model was proposed to fit the impurity concentration as a function of the repetition number of the Bridgman growths, as well as determine the segregation coefficients of impurities in the crystals. The crystalline structure, the stoichiometry, and the surface morphology of the crystals were evaluated, systematically, for the crystals grown with different purification numbers. To evaluate the crystal as a radiation semiconductor detector, measurements of its resistivity and gamma-ray spectroscopy were carried out, using 241Am and 133Ba sources. A significant improvement of the radiation response was observed in function of the crystal purity.
Industrial tomography using three different gamma ray
2016 - MESQUITA, C.H. DE; VELO, A.F.; CARVALHO, D.V.S.; MARTINS, JOAO F.T.; HAMADA, M.M.
Methodological analysis of gamma tomography system for large random packed columns
2010 - VASQUEZ, PABLO A.S.; MESQUITA, CARLOS H. de; LEROUX, GALO A.C.; HAMADA, MARGARIDA M.
Radiation damage studies on the optical and mechanical properties of plastic scintillators
1999 - HAMADA, M.M.; RELA, P.R.; COSTA, F.E.; MESQUITA, C.H.
Radiation damage in scintillator detector chemical compounds: a new approach using PPO-toluene liquid scintillator as a model
2002 - MESQUITA, C.H.; FERNANDES NETO, J.M.; DUARTE, C.L.; RELA, P.R.; HAMADA, M.M.
Analise do dano de radiacao gama em detectores organicos contendo PPO
2002 - FERNANDES NETO, J.M.; MESQUITA, C.H.; DUARTE, C.L.; HAMADA, M.M.
Radiation physical chemistry effects on organic detectors
2003 - MESQUITA, C.H.; DUARTE, C.L.; HAMADA, M.M.
Gamma-ray computed tomography SCANNERS for applications in multiphase system COLUMNs
2009 - CALVO, WILSON A.P.; HAMADA, MARGARIDA M.; SPRENGER, FRANCISCO E.; VASQUEZ, PABLO A.S.; RELA, PAULO R.; MARTINS, JOAO F.T.; PEREIRA, JOAO C.S. de M.; OMI, NELSON M.; MESQUITA, CARLOS H. de
Gamma-ray tomography experiments have been carried out to detect spatial patterns in the porosity, in a 0.27 m diameter packed steel column using a first generation computed tomography (CT) system. The CT scanner consists of a NaI(Tl) detector 5.08 cm in diameter, and an encapsulated 137Cs (3.7 GBq) radioactive source, located opposite to the center of the detector. The detector and the source, mounted on a fixed support and the column, can rotated and dislocate by two stepping motors controlled through a microprocessor. Different sizes of stainless steel Raschig rings (12.6, 37.9 and 76 mm) have been examined. The primary objective of this work is to detect spatial patterns and statistical information on porosity variation in packed distillation columns. Horizontal scans, at different vertical positions of the packed bed were made for each size of Raschig rings. Radial porosity variation within the packed bed has been determined. This study has demonstrated that the porosity and its spatial distribution in a metallic packed column can be measured with adequate spatial resolution using the gamma-ray tomography technique. After validation of this first generation CT, the turntable design to rotate and dislocate the 60Co or 137Cs sealed gamma-ray sources and multidetector array for the third generation industrial computed tomography was also developed.