REYNALDO PUGLIESI
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Artigo IPEN-doc 27718 Concentration and distribution of oil in the reservoir mineral Dolomite studied by neutron tomography2020 - PUGLIESI, R.; STANOJEV PEREIRA, M.A.; ANDRADE, M.L.Neutron Tomography – NT is a non-destructive technique, ideal for imaging hydrogen-rich substances even when wrapped up by thick rock layers. In the present study, the NT was employed for investigating the oil concentration and distribution in the mineral Dolomite, a natural oil reservoir. Two types of Dolomite samples, one of which dry, and the second one in oil-saturated were prepared. The applied oil was EMCAplus® 070 usually employed in permeability experiments to reproduce conditions of natural oil reservoirs. Three small fragments of the dry sample and three of the oil sample were inspected by NT and the comparison between the obtained results enabled, to distinguish several regions in which the oil is stored, to indicate that the oil is dispersed throughout the volume of the samples, and to quantify the storage concentration. The obtained data for oil concentration, for the three fragments, were compared to each other and to the one obtained by the conventional gravimetric technique, and they agreed within their uncertainties, demonstrating the viability of the NT technique to inspect, either in a qualitative as in a quantitative level, this oil reservoir mineral.Artigo IPEN-doc 26439 Estudo da mineralização de cobre em basaltos do Grupo Serra Geral, utilizando difratometria de raios X, microscopia eletrônica de varredura-espectroscopia por energia dispersiva e tomografia com nêutrons2019 - GARDA, GIANNA M.; FILGUEIRA, DIEGO A.; PUGLIESI, REYNALDO; PEREIRA, MARCO A.S.; SAYEG, ISAAC J.Mineralizações de cobre do tipo Michigan ocorrem nos derrames basálticos do Grupo Serra Geral na região de Nova Prata do Iguaçu, sudoeste do estado do Paraná. Nessas mineralizações, o cobre nativo é o principal mineral de minério e, com a alteração supérgena, transforma-se em óxidos de cobre, malaquita e crisocola, sendo esta encontrada na forma de um precipitado gelatinoso que preenche amígdalas e impregna fraturas no basalto, além de recobrir minerais secundários e outros produtos de alteração. Neste estudo, foram utilizadas as técnicas de difratometria de raios X e microscopia eletrônica de varredura-espectroscopia por energia dispersiva (MEV-EDS) para a caracterização do grau de cristalinidade e composição química da crisocola e a identificação de outros materiais hidrogenados, como subsídio para o imageamento 3D por tomografia com nêutrons. A crisocola destacou-se como um eficiente atenuador de nêutrons, obtendo-se coeficiente de atenuação linear da ordem de 0,8–1,3 cm-1, ao passo que, para o corpo de minério (basalto), obteve-se 0,5–0,6 cm-1. O contraste entre os coeficientes permitiu a obtenção de imagens tomográficas e filmes de boa resolução, em que se pôde visualizar a distribuição da crisocola na amostra de basalto e estimar como fração volumétrica de crisocola no corpo de minério valores entre 0,9 e 1,4%, obtendo-se o valor de 7,8% em volume de crisocola para uma das amostras. A utilização integrada das três técnicas analíticas demonstrou que esta pode ser uma ferramenta para avaliação do potencial mineral nas fases iniciais da prospecção mineral, especialmente quando as substâncias de interesse são ricas em hidrogênio.Resumo IPEN-doc 25924 Caracterização da mineralização epigenética de cobre na região de Nova Prata do Iguaçu, Estado do Paraná, por microscopia eletrônica de varredura e tomografia de nêutrons2018 - FILGUEIRA, D.A.; GARDA, G.M.; PUGLIESI, R.; PEREIRA, M.A.S.; SAYEG, I.J.Dentre os fatores que contribuem para a mineralização epigenética destacam-se a porosidade e a permeabilidade da rocha hospedeira da mineralização. Os fluidos mineralizantes transportam elementos que, dependendo das condições físico-químicas do meio, precipitam-se, podendo vir a formar depósitos minerais. Em Nova Prata do Iguaçu afloram níveis de rocha basáltica mineralizados em cobre, que se apresenta na forma nativa, como óxidos (tenorita, cuprita), como carbonato (malaquita) e silicato (crisocola). A presença de amígdalas, vesículas e geodos na rocha basáltica confere à mesma tanto a permeabilidade necessária para a percolação dos fluidos mineralizantes, como os espaços (vazios) para a precipitação de minerais de minério e minerais secundários associados ou não aos fluidos mineralizantes. Por espectroscopia de energia dispersiva de raios X acoplada à microscopia eletrônica de varredura (EDS/MEV) foram analisados minerais de minério e minerais secundários (analcima, variedades de quartzo, feldspato), dando-se atenção especial à crisocola, cuja variação de cores está relacionada às concentrações de cobre, alumínio e ferro nesse mineralóide. Assim, a crisocola laranja apresenta concentrações de cobre entre 30 e 36% e de alumínio + ferro de até 6%, ao passo que a crisocola azul apresenta concentrações de cobre entre 40 e 41,5% (e não contém alumínio ou ferro). Quanto aos carbonatos e óxidos de cobre, as concentrações de cobre nesses minerais variam entre 62-53% e 74-81%, respectivamente. A técnica da tomografia com nêutrons foi utilizada para investigar a distribuição dos minerais de cobre em amostras de basalto vesicular, empregando-se o equipamento do IPEN-CNEN/SP que está instalado no Reator Nuclear de Pesquisas IEA-R1. Além de não destrutiva, a técnica possibilitou a visualização das estruturas internas do basalto (vesículas preenchidas ou vazias) e a estimativa da proporção em volume de vazios, de cobre nativo e de crisocola. Foram tomografados três amostras de minério e as porcentagens obtidas para os vazios foram 26%, 29% e 31% e a de minerais de cobre 1,1%, 1,7% e 2,4%, respectivamente. O método também se mostrou eficiente no imageamento de cobre nativo. Apesar de não discriminar os silicatos e carbonatos secundários que também preenchem as vesículas do basalto, estes puderam ser identificados por microscopia óptica, difração de raios X e EDS/MEV nos laboratórios do IGc-USP. Assim, o uso da tomografia de nêutrons, associados a técnicas analíticas, como o EDS/MEV, em amostras provenientes de perfis de alteração hidrotermal/intempérico de sequências basálticas contribui para caracterização não só das estruturas da rocha, mas também dos níveis mineralizados e não mineralizados e no entendimento do processo mineralizante.Artigo IPEN-doc 25827 Study of the fish fossil Notelops brama from Araripe-Basin Brazil by Neutron Tomography2019 - PUGLIESI, REYNALDO; PEREIRA, MARCO A.S.; ANDRADE, MARCOS L.G.; BASSO, JULIANA M.L.; VOLTANI, CIBELE G.; GONZALES, IVONE C.In the last decade, Neutron Tomography significantly gained importance as an analyzing tool to inspect samples of paleontological interest. In general, neutrons are able to provide new and complementary information when compared to the ones provided by X-rays imaging methods. Specifically, in the present paper, the Neutron Tomography equipment of the IPEN-CNEN/SP was successfully applied to investigate the internal structure of a fish fossil, embedded in a calcareous concretion. The resulting images, which will be presented, has revealed different contrast between several regions within the specimen enabling the differencing of osteological structures of the fossil, information about its state of conservation, degree of embedding, inclusions as well as regions within the concretion which could be related to humidity or to other substances and minerals containing hydrogen naturally added to the fossil. The technique is non-destructive and non-invasive allowing a close analysis of the specimen. Furthermore, the obtained images have demonstrated the feasibility of the equipment at IPENCNEN/ SP for investigating this kind of sample.Artigo IPEN-doc 25825 Spatially resolved oxygen reaction, water, and temperature distribution2019 - LOPES, THIAGO; BERUSKI, OTAVIO; MANTHANWAR, AMIT M.; KORKISCHKO, IVAN; PUGLIESI, REYNALDO; STANOJEV, MARCO A.; ANDRADE, MARCOS L.G.; PISTIKOPOULOS, EFSTRATIOS N.; PEREZ, JOELMA; FONSECA, FABIO C.; MENEGHINI, JULIO R.; KUCERNAK, ANTHONY R.In situ and ex situ spatially-resolved techniques are employed to investigate reactant distribution and its impacts in a polymer electrolyte fuel cell. Temperature distribution data provides further evidence for secondary flows inferred from reactant imaging data, highlighting the contribution of convection in heat as well as reactant distribution. Water build-up from neutron tomography is linked to component degradation, matching the pattern seen in the reactant distribution and thus suggesting that high, non-uniform local current densities shape degradation patterns in fuel cells. The correlations shown between different techniques confirm the use of the versatile reactant imaging technique, which is used to compare commonly used flow field designs. Among serpentine-type designs, the single serpentine is superior in both equivalent current density and reactant distribution, showing large contributions from convective flow. On the other hand, the interdigitated design is shown to produce larger equivalent current densities, while showing a somewhat poorer reactant distribution. Considering the correlations drawn between the techniques, this suggests that the interdigitated design compromises durability in favour of power output. The results highlight how established techniques provide a robust background for the use of a new and flexible imaging technique toward designing advanced flow fields for practical fuel cell applications.Artigo IPEN-doc 24774 Penetration of the consolidant Paraloid (R) B-72 in Macuxi indigenous ceramic vessels investigated by neutron tomography2018 - PEREIRA, MARCO A.S.; PUGLIESI, REYNALDOThe neutron tomography technique was applied in studying the penetration of the consolidant Paraloid (R) B-72 in contemporary indigenous ceramic vessels. The study was carried out for two distinct and controlled air humidity conditions, 40% and 90%, in which the vessels were exposed, before the consolidant application. The obtained images have proved that the penetration of Paraloid (R) B-72 in the ceramic does not depend on the humidity condition in which it was applied, moreover allowed a macro-visualization of the consolidant penetration in the ceramic vessel. As the vessels used in the present work were manufactured by an indigenous artisan, Macuxi, according to the same procedures and raw materials used by the ancient artisans, the results obtained can be used as a guide to assist experts, both in the study of archeological objects of Macuxi origin, as well as other objects that had been made by other tribes that lived in the same Amazon region, in Brazil.Resumo IPEN-doc 23391 Neutron tomography at IPEN-CNEN/SP: images and applications2016 - PUGLIESI, REYNALDO; PEREIRA, MARCO A.S.; ANDRADE, MARCOS L.G.The neutron tomography is a non destructive testing technique used to inspect the internal structure of a sample by means of tridimensional digital images. Because of the neutron-matter interaction characteristics this technique can be used to inspect hydrogen-rich substances like ceramics, oil, grease, water, rubber, blood and others, even wrapped by thick metal layers. In this way, the information provided by neutrons are complementary to the ones provided by Xrays. The Brazilian Institute for Nuclear Technology IPEN-CNEN/SP has an equipment for neutron tomography which since Nov/2011 is operational and installed at the IEA-R1 Nuclear Research Reactor. This equipment is able to provide high quality tomographs and some important results obtained for Proton Exchange Membranes (PEM) cell, for an archaeological sample and for pottery, will be presented. Furthermore, details of its construction and its versatility, in the sense that by means of small adjustments is possible to obtain images by other neutron imaging techniques, will be also presented. Is very important enhance that the high quality of the obtained images is due to the excellence of the IEA-R1 reactor which is able to furnish neutron beams with adequate intensity for such purpose.Artigo IPEN-doc 23100 Method to evaluate the L/D ratio of neutron imaging beams2017 - PUGLIESI, R.; PEREIRA, M.A.S.; SCHOUERI, R.M.An alternative simple method to evaluate the L/D ratio of neutron imaging beams is proposed. It is based on the behavior of the ratio “x/Ut”, which asymptotically tends to L/D for large values of the parameter “x”, that corresponds to the distance separating a gadolinium test object to the scintillator plane, where its image is formed. The method was applied to the neutron imaging equipment of the Nuclear and Energy Research Institute IPENCNEN/ SP and the obtained result was L/D = (104 ± 4). The consistency of the proposed method was verified by comparing this value with those ones obtained by a well - known and established procedure.Artigo IPEN-doc 23097 Penetração e distribuição do consolidante Paraloid® B-72 em cerâmica branca estudada por tomografia com nêutrons2017 - PEREIRA, MARCO A.S.; PUGLIESI, REYNALDO; ANDRADE, MARCOS L.G.; PRUDENCIO, MARIA I.ASSESSMENT OF PARALOID® B-72 PENETRATION IN WHITE CERAMIC STUDIED BY NEUTRON TOMOGRAPHY. The neutron tomography technique was employed to study the penetration and distribution of the consolidant Paraloid® B-72 in ceramic. This study was carried out in white contemporary ceramic vessels which were maintained in two distinct and controlled air humidity conditions, 35% and 90%, before the consolidant application (brushing technique). The results showed that the treatment with Paraloid® B-72 is more effective when applied in the drier vessel. The depth of penetration for the vessel at 35%, reaches (3.3 ± 0.1) mm in the wall, while for the one at 90%, (1.9 ± 0.1) mm, and the maximal concentration impregnation was 26% higher. The 3D images allowed a visualization of the impregnation process, that is, its distribution, failures, homogeneity, boundary between materials. These results demonstrated the feasibility of the neutron tomography technique and of the equipment of IPEN-CNEN/SP, in support the expert work in the field of preservation and restoration of ceramic objects.Artigo IPEN-doc 21332 Study of pixel damages in CCD cameras irradiated at the neutron tomography facility of IPEN-CNEN/SP2015 - PUGLIESI, R.; ANDRADE, M.L.G.; DIAS, M.S.; SIQUEIRA, P.T.D.; PEREIRA, M.A.S.