MARCOS LEANDRO GARCIA ANDRADE

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  • Artigo IPEN-doc 27718
    Concentration and distribution of oil in the reservoir mineral Dolomite studied by neutron tomography
    2020 - 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 25827
    Study of the fish fossil Notelops brama from Araripe-Basin Brazil by Neutron Tomography
    2019 - 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 distribution
    2019 - 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.
  • Resumo IPEN-doc 23391
    Neutron tomography at IPEN-CNEN/SP: images and applications
    2016 - 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 23097
    Penetração e distribuição do consolidante Paraloid® B-72 em cerâmica branca estudada por tomografia com nêutrons
    2017 - 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/SP
    2015 - PUGLIESI, R.; ANDRADE, M.L.G.; DIAS, M.S.; SIQUEIRA, P.T.D.; PEREIRA, M.A.S.
  • Artigo IPEN-doc 20728
    Neutron imaging at the IPEN-CNEN/SP and its use in technology
    2014 - PUGLIESI, R.; ANDRADE, M.L.G.; PEREIRA, M.A.S.; SCHOUERI, R.M.; DIAS, M.S.
  • Artigo IPEN-doc 20649
    The new facility for neutron tomography of IPEN-CNEN/SP and its potential to investigate hydrogenous substances
    2014 - SCHOUERI, R.M.; DOMIENIKAN, C.; TOLEDO, F. de; ANDRADE, M.L.G.; STANOJEV PEREIRA, M.A.; PUGLIESI, R.
  • Capítulo IPEN-doc 15622
    Fundamentos da tecnica da radiografia com neutrons
    2007 - PUGLIESI, REYNALDO; ANDRADE, MARCOS L.G.; PEREIRA, MARCO A.S.; PUGLIESI, FABIO
  • Resumo IPEN-doc 05107
    Effect of the scattered neutrons in radiography sensitivity
    1996 - MENEZES, M.O.; PUGLIESI, R.; ANDRADE, M.L.G.; PEREIRA, M.A.S.