Reposiório IPEN: Recent submissions

  • IPEN-DOC 25933

    OLIVEIRA, PATRICIA da S.P. de ; ANDREA, VINICIUS ; SANTIAGO, ELISABETE I. ; LOPES, THIAGO ; ANDRADE, DELVONEI A. de ; LINARDI, MARCELO . A reliability-based strategy for the analysis of single proton exchange membrane fuel cells. Energy and Power Engineering, v. 11, n. 8, p. 303-319, 2019. DOI: 10.4236/epe.2019.118019

    Abstract: The development of power conversion systems based on fuel cells has been demanding reliability studies since the requirements associated with cost and durability of these technological products have become fundamental to their acceptance by the energy market. The experimental part of the reliability study presented in this work consisted of performing life tests with single proton exchange membrane fuel cells (PEMFCs). The proposed reliability analysis methodology covered the application of qualitative and quantitative techniques. In the qualitative approach, a Failure Mode and Effect Analysis was developed in order to identify and evaluate all potential failures associated with the operation of fuel cells. In the quantitative approach, a statistical analysis was applied to the sample data generated in long-term steady-state tests of these devices. A two-parameter exponential distribution was fitted to data and the maximum likelihood estimate for the mean time to failure (MTTF) of the fuel cells was calculated. It is important to point out that the tests performed under the scope of this study were the first long-term experiments performed with the fuel cells produced in the laboratories of IPEN-CNEN/SP, Brazil. Although the results indicated that fuel cell performance and durability were still at a level below the targets normally established for similar commercial devices, the improvement of the main components of PEMFCs has been the objective of several projects developed at the institute. Thus, the main benefit brought by this study is the proposed methodology, which can be implemented as part of a reliability growth analysis of the fuel cells and can be integrated into the design process of these devices.

    Palavras-Chave: fuel cells; reliability; durability; lifetime; energy; failures; hydrogen; brazilian cnen

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  • IPEN-DOC 25932

    GONÇALVES, KARINA de O.; SILVA, FLAVIA R. de O. ; VIEIRA, DANIEL P. ; COURROL, LILIA C.. Synthesis of hybrid AuFe nanoparticles by photoreduction and methyl aminoluvinate. In: SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, October 08-10, 2018, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2018. DOI: 10.1109/SBFoton-IOPC.2018.8610950

    Abstract: The nanohybrid gold/iron (AuFe) system is particularly interesting for biomedical applications such as targeted drug delivery, hyperthermia and photodynamic therapy (PDT) mainly due to its magnetic combined to the plasmonic properties. In this study, we aimed to synthesize nanohybrids to be used as a vehicle to deliver Methyl Aminoluvinate (MAL) for selective and efficient PDT. MAL is a prodrug that is metabolized to protoporphyrin IX (PpIX), photosensitizer in PDT. The nanohybrids were synthesized by photoreduction of solutions containing iron powder, polyethylene glycol (PEG), chloroauric acid (HAuCl4) and MAL as a reducing agent in water solution. The products were characterized by UV-Vis, zeta potential and transmission electron microscopy. The synthesized nanoparticles had the optical properties of metallic nanoparticles and the magnetic properties of iron nanoparticles. Their characteristic absorption bands, in the visible light range, became become broader and red‐shifted in the presence of iron nanoparticles. Cell viability of cancer cell lines in the presence of nanohybrids studies were performed.

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  • IPEN-DOC 25931

    SAITA, MARCELO T.; BARBOSA, EDUARDO A.; DEGASPERI, FRANCISCO T.; WETTER, NIKLAUS U. . Pressure measurement by low coherence speckle interferometry membrane shaping with tunable diode lasers. In: SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, October 08-10, 2018, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2018. DOI: 10.1109/SBFoton-IOPC.2018.8610915

    Abstract: Non-contact evaluation of object deformation is of great importance in several industrial and scientific processes. In this work the demonstrate that low-coherence digital speckle pattern interferometry can be employed for pressure measurement by the analysis of a 0.4-mm thickness, 55-mm diameter circular aluminum membrane submitted to a pressure differential ranging from 0 to 90 kPa. The membrane deformation was measured with a tunable red diode laser emitting simultaneously two wavelengths. The resulting speckle image of the membrane appeared covered with interference fringes which correspond to the contour lines of the studied surface. By means of conventional fringe pattern evaluation methods like 4-stepping and unwrapping methods the membrane deformation was determined. The experimental results were compared with the ones obtained by a numerical algorithm.

    Palavras-Chave: interferometry; optical equipment; deformation; measuring methods; pressure measurement; lasers; laser cavities

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  • IPEN-DOC 25930

    SAMAD, RICARDO E. ; ZUFFI, ARMANDO V.F. ; MALDONADO, EDISON P.; VIEIRA JUNIOR, NILSON D. . Development and optical characterization of supersonic gas targets for high-intensity laser plasma studies. In: SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, October 08-10, 2018, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2018. DOI: 10.1109/SBFoton-IOPC.2018.8610903

    Abstract: Laser particle acceleration is a rapid growing field due to the compactness and smaller cost when compared to traditional accelerators, as well as the potential for new applications resulting from the unique characteristics of the beams generated. Frequently, laser acceleration techniques require laser intensities higher than 100's of PW/cm2 and highdensity gas targets, with specific profiles. In the effort to implement laser electron acceleration in our laboratories, we report the development of submillimetric, supersonic gas nozzles, the implementation of optical techniques for the determination of the gas jets density profiles, and the characterization of laser-induced plasmas obtained at laser intensities surpassing 1016 W/cm2. The characterization techniques employed include plasma spectroscopy, interferograms and Schlieren images.

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  • IPEN-DOC 25929

    ZUFFI, ARMANDO V.F. ; ALMEIDA, ANDREIA A. ; VIEIRA JUNIOR, NILSON D. ; SAMAD, RICARDO E. . Characterization of below threshold harmonics generated in argon by ultrashort laser pulses. In: SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, October 08-10, 2018, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2018. DOI: 10.1109/SBFoton-IOPC.2018.8610890

    Abstract: This work reports studies on the generation of below threshold harmonics by ultrashort laser pulses in gas nozzles in vacuum. Odd harmonics of the laser, ranging from the 3rd up to the 9th, were generated in the UV and VUV regions, and the frequency conversion occurred in flowing gas. The harmonics were spectrally characterized, and the orders of the nonlinear processes were determined, showing that, for the higher order harmonics, competing processes decrease the energy coupling into the new frequencies. Also, the conversion efficiencies were estimated, showing that a few percent of the laser pulse energy are converted into the harmonics.

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  • IPEN-DOC 25928

    LIMA, SAMIA R.M. ; FAUSTINO, MAINARA G. ; SANTOS, EDDY B. dos ; SILVA, TATIANE B.S.C. da ; PIRES, MARIA A.F. ; COTRIM, MARYCEL E.B. . Caracterização das frações de fósforo no sedimento superficial dos rios Aracaí, Carambeí e Guaçu na cidade de São Roque/SP. In: CONGRESSO BRASILEIRO DE GEOLOGIA DE ENGENHARIA E AMBIENTAL, 16., 2-6 de setembro, 2018, São Paulo, SP. Anais... São Paulo: ABGE, 2018. p. 1-10.

    Abstract: Neste trabalho foi realizado o fracionamento do fósforo nos sedimentos dos rios Aracaí, Carambeí e Guaçu da cidade de São Roque/SP. O método analítico utilizado foi o Protocolo desenvolvido pelo Standards, Measurements and Testing (SMT), que fracionou o fósforo nos sedimentos em total (PT), inorgânico (PI), orgânico (PO), não apatítico (PINA) e apatítico (PIA). Teve por objetivo avaliar a distribuição e fracionamento do fósforo nos sedimentos dos principais rios da região, a fim de verificar a contribuição do fósforo no processo de eutrofização, além dos demais impactos antrópicos que possam implicar na qualidade das águas dos rios do Município. Para tanto, foram avaliados 5 pontos amostrais, determinadas concentração de PT, PO, PI, PIA e PINA, juntamente com os parâmetros físico-químicos (granulometria, pH, e matéria orgânica). As maiores concentrações ocorreram nos sedimentos do ponto G4 com 456,9 mg.kg-1 para PT. Os teores de PI foram maiores que os de PO na maioria dos pontos. Os teores de sedimentos finos e de matéria orgânica foram os principais parâmetros ambientais correlacionados com as frações de fósforo. De acordo com a resolução CONAMA 344/04, as concentrações de fósforo encontradas estão abaixo do nível estabelecido.

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  • IPEN-DOC 25927

    NASCIMENTO, S.F.; RIBEIRO, C.; FERREIRA, T.S. ; GUEDES-SILVA, C.C. . Reatividade in vitro de nitreto de silício contendo SiO2 e SrO. In: CONGRESSO BRASILEIRO DE ENGENHARIA E CIÊNCIA DOS MATERIAIS, 23., 04-08 de novembro, 2018, Foz do Iguaçu, PR. Resumo... 2018. p. 4-4.

    Abstract: Nesse trabalho, biocompósitos densos de nitreto de silício foram estudados visando sua utilização como componentes e dispositivos protéticos que requeiram boa interação com o tecido ósseo. Para tanto, cerâmicas de nitreto de silício em diferentes composições contendo SiO2 e SrO foram obtidas. Os aditivos foram selecionados para contribuir com a bioatividade e habilidade do material final em se ligar com o osso. Além disso, a liberação de estrôncio no paciente promove a proliferação de osteoblastos, aumentando o potencial do material para aplicações biomédicas. Dessa forma, o presente trabalho tem como objetivo avaliar o comportamento biológico in vitro de cerâmicas de nitreto de silício contendo SiO2 e SrO, por meio de testes de imersão em SBF (simulated body fluid). Os resultados mostraram que as composições estudadas conduziram à formação de depósitos contendo fósforo e cálcio superficial após 4 dias de imersão, demonstrando a capacidade dos materiais para aplicações na cirurgia maxilofacial, sistemas de miniosteofixação, espaçadores na fusão intervertebral e raízes dentais.

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  • IPEN-DOC 25926

    FERREIRA, T.S. ; CARVALHO, F.M.S.; GUEDES-SILVA, C.C. . Avaliação das propriedades mecânicas e da resistência à oxidação de compósitos cerâmicos Si3N4-TiN. In: CONGRESSO BRASILEIRO DE ENGENHARIA E CIÊNCIA DOS MATERIAIS, 23., 04-08 de novembro, 2018, Foz do Iguaçu, PR. Resumo... 2018. p. 1254-1254.

    Abstract: Embora cerâmicas à base de Si3N4 já sejam utilizadas em diversas aplicações estruturais, vários compósitos de nitreto de silício têm sido estudados com o intuito de melhorar ainda mais suas propriedades mecânicas, principalmente a tenacidade à fratura. O presente trabalho visa avaliar as propriedades mecânicas e a resistência à oxidação de compósitos de Si3N4/TiN (até 30% em peso de TiN), contendo Al2O3 e Y2O3 (5% em peso de cada) como aditivos de sinterização. Amostras obtidas por prensagem uniaxial e isostática, sinterizadas a baixa pressão de nitrogênio a 1750ºC / 1 hora e 1815ºC / 1 hora, foram caracterizadas quanto à dureza e à tenacidade à fratura pelo método da impressão Vickers. O comportamento de oxidação foi avaliado por meio de tratamentos térmicos ao ar a 1400ºC por até 64 horas. Os resultados obtidos mostraram que as amostras atingiram valores de dureza entre 12,5 e 13,1 GPa, enquanto a tenacidade à fratura variou entre 6,3 e 9,3 MPa.m1/2, aumentando juntamente com a proporção de TiN no compósito cerâmico e superando os valores apresentados pelo nitreto de silício. Os testes de resistência à oxidação apresentaram valores de ganho de massa por área entre 0,7 e 6,4 mg/cm2, crescentes em função do teor de TiN presente no compósito e do tempo de exposição ao ar a 1400ºC.

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  • IPEN-DOC 25925

    SALVETTI, TEREZA C. ; MARUMO, JULIO T. . Comparative study of the standards and guides of a management system applicable to radioactive waste. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 44th, March 18-22, 2018, Phoenix, Arizona, USA. Proceedings... Arizona, USA: Waste Management Symposia, 2018. p. 1-9.

    Abstract: A Management System may be defined as a set of standardized and interrelated practices that aim to improve effectiveness and produce better results. This system should be structured in such a way as to allow essential information to flow properly within the organization, including technical, administrative, production and human resources information, among others, within an adopted compliance model. There are, currently, several standards and guidelines for structuring a compliance model related to a management system. A system that covers various aspects of management in a single system is usually called integrated. Only the International Atomic Energy Agency - IAEA has a guide with this approach for radioactive waste: GS-G-3.3, "The Management System for the Processing, Handling and Storage of Radioactive Waste" and GS-G-3.4, "The Management System for the Disposal of Radioactive Waste". The objective of this work is to present a comparison between existing standards, even if not specific for the management of radioactive waste, but which are widely used by companies. In due course, the result of this work will be object of proposal for specific standard to be presented to regulatory agency for this type of activity. This study should be useful for countries where there are no specific guidelines by the regulatory agency, adopting the best standard or guide as a conformity standards, creating and establishing a hybrid structure best suited to the safety and security aspects of the local culture.

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  • IPEN-DOC 25924

    FILGUEIRA, D.A.; GARDA, G.M.; PUGLIESI, R. ; PEREIRA, M.A.S. ; SAYEG, I.J.. Caracterização da mineralização epigenética de cobre na região de Nova Prata do Iguaçu, Estado do Paraná, por microscopia eletrônica de varredura e tomografia de nêutrons. In: PALERMO, NELY (Ed.); ARAUJO JUNIOR, HERMINIO I. de (Ed.); MACHADO, FABIO B. (Ed.); CORVAL, ARTUR (Ed.); VALENTE, SERGIO de C. (Ed.); DAL'BÓ, PATRICK F. (Ed.) CONGRESSO BRASILEIRO DE GEOLOGIA, 49.; SIMPÓSIO DO CRETÁCEO DO BRASIL, 9.; SIMPÓSIO DE VULCANISMO E AMBIENTES ASSOCIADOS, 7., 20-24 de agosto, 2018, Rio de Janeiro, RJ. Resumo... São Paulo: Sociedade Brasileira de Geologia, 2018. p. 1706-1706.

    Abstract: 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.

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  • IPEN-DOC 25923

    LEAL, L.G.M. ; ZAMBONI, C.B. ; FROTA, L.O.O. ; SIMON, M.S.L.; NASCINTO, R.M.. Caracterização multielementar do pólen da abelha Scaptotrigonaaff postica utlizando técnica de fluorescência de raios X. In: CONGRESSO BRASILEIRO DE APICULTURA, 22.; CONGRESSO BRASILEIRO DE MELIPONICULTURA, 7., 16-19 de maio, 2018, Joinville, SC. Resumo... 2018. p. 30-30.

    Abstract: Nos últimos anos a procura por produtos naturais e saudáveis cresceu significativamente e produtos oriundos da Meliponicultura (criação de abelhas sem ferrão), passaram a ser consumidos em maior escala no Brasil. Especificamente, o pólen tem ganhado destaque no âmbito nutricionalpor ser uma fonte proteica(16 a 40 %, contendo vários aminoácidos) e rica em carboidratos, lipídeos, oligoelementos minerais, fibras, hormônios e vitaminas. O pólen tem sido considerado um superalimento, mas investigação cientificas ainda são escassas, especialmente no que concerne estudos de suas propriedades especificas.O objetivo desta investigação foi avaliar o teor dos elementos inorgânicos (realização de análise multielemntar) em pólen de abelhas Scaptotrigonaaff. postica, proveniente da região de Barra do Corda, no estado do Maranhão. As analises foram realizadas utilizando espectrômetro de Fluorescência de Raios X (X-123SDD, Amptek) equipado com tubo de Raio de X de Prata e detector de Silício (Si Drift 25 mm2 x 500μm) com janela de Berílio de 0.5mil. Na análise multielementar Ca, Cl, Fe e K correspondem aos componentes majoritários enquanto P, S e Zn estão presentes como elementos traços. As concentrações obtidas encontram-se dentro dos limites máximos recomendados na legislação nacional. Essas estimativas compõem as primeiras avaliações de oligoelementos minerais deste produto natural e fornecem subsídio a apicultores à respeito de suas caraterística especificas além de contribuir com dados a relevantes no âmbito nutricional.

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  • IPEN-DOC 25922

    GUEDES, ANDERSON G.; LANDULFO, EDUARDO ; HOELZEMANN, JUDITH; LOPES, FABIO J.S. ; SILVA, MARCOS P.A.; SANTOS, RENATA S.S.; GUERRERO-RASCADO, JUAN L.; ALADOS-ARBOLEDAS, LUCAS; DUARTE, EDICLE S.F.. Evaluation of the transport of atmospheric Sahara dust on Natal-RN through the LIDAR technique of depolarization. In: INTERNATIONAL WORKSHOP ON SAND/DUSTSTORMS AND ASSOCIATED DUSTFALL, 9th, May 22-24, 2018, Tenerife, Spain. Abstract... 2018. p. 249-249.

    Abstract: The objective of this work is describe some results of the Natal LIDAR system (DUSTER), an integrating station of The Latin America Lidar Network (LALINET), aimed to detect and evaluate the transcontinental transport of Sahara dust (SD) to the Brazilian territory during the aerosol MOnitoring campaign Long-­‐range Transportation OVer Natal I (MOLOTOV I) which occurred from December 2016 to February 2017. The city of Natal is located in northeastern Brazil and is one of the continental points closest to the African continent, a important fact to observe the entry of SD in the South American continent. The DUSTER system allows the detection of signals at wavelengths of 355 nm, 532 nm (parallel), 532 nm (perpendicular) and 1064 nm. To detect and characterize SD aerosols and other particles in the atmosphere, DUSTER uses the ability of suspended aerosol particles to change the polarization state of light. The data retrieved by DUSTER allow calculate fundamental parameters in the characterization of atmospheric aerosols such as linear volume depolarization ratio (𝛿!) and particle linear depolarization ratio (𝛿!). Campaign data showed that on a few days the value of 𝛿! varied between 0.09 and 0.33 at a transport altitude within the range of 1-­‐3.3 km above sea level indicating in some cases probably a mixture of SD with other types of aerosols such as marine particles, anthropogenic pollution or biomass burning smoke. The data obtained with DUSTER have allowed verify the seasonality of this transport, the altitudes of detected particles and study its optical properties.

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  • IPEN-DOC 25921

    MAZIERO, J.S. ; CAVALCANTE, A.K. ; MARTINI, G.A. ; DAMASCENO, K.C. ; ORMENIO, M.B. ; CAVALCANTE, B.K. ; ROGERO, S.O. ; ROGERO, J.R. ; LUGAO, A.B. . In vitro and in vivo toxicity evaluation of silver nanoparticles stabilized with gum arabic. In: WORKSHOP ON ENVIRONMENTAL NANOTECHNOLOGY, 3rd, October 5-8, 2018, Sorocaba, SP. Abstract... 2018. p. 49-49.

    Abstract: Due to its properties such as size, varied shape, high surface area and high bactericidal properties, silver nanoparticles (AgNP) have been widely used in several sectors of the industry: bandages; inside food coolers, to retard spoilage; in antimicrobial insoles, to prevent odors; in air purifiers; in surgical instruments and etc [1] [2]. Considering the range of applications a great concern in the academic field, mainly ecotoxicological, as the potential impacts and risks that AgNP can cause to the environment and human health has increased. During the synthesis of AgNP it is necessary to use stabilizing agents such as gum arabic (GA), which is an exudate of dried gum, edible, from the stems and branches of Acacia senegal and A. seyal, rich in soluble fiber not viscous. GA has broad industrial use as stabilizer, thickening agent and emulsifier [3]. Based on these considerations, this work aimed to verify and compare the toxicity level of two GA-stabilized AgNP samples (Sample 1: AgNP at 147 ppm concentration, approximately 25 nm in size; and Sample 2: AgNP at concentration of 174 ppm with approximate size of 75 nm) using in vitro and in vivo assays. The in vitro cytotoxicity test was performed according to ISO 10993-5 by the neutral red uptake method in cells of the NCTC-L929 line, to obtain the IC50 (cytotoxicity index, which is the concentration of the substance causing it 50% mortality of exposed cells); and the in vivo acute ecotoxicity assay, according to the Brazilian standard ABNT NBR 12713, using Daphnia similis as the test organism to obtain EC50 (effective concentration that causes immobility in 50% of exposed organisms). The results obtained for Sample 1 were IC50 of 2.57 mg L-1 and EC50 of 4.40 μg L-1; and Sample 2: IC50 of 2.61 mg L-1 and EC50 of 6.55 μg L-1. These results demonstrated that aquatic organisms are much more sensitive to AgNP than cells in culture, raising the importance of conducting further studies related to the adversities that these nanoparticles can cause to the environment and human health. In addition, it is necessary to verify the disposal of the same in the environment, since in Brazil there are still no legislation that quantifies the permissible limits for this disposal.

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  • IPEN-DOC 25920

    GIMILIANI, G.T. . An overview of nanoplastics present in the environment: a new group of nanomaterials?. In: WORKSHOP ON ENVIRONMENTAL NANOTECHNOLOGY, 3rd, October 5-8, 2018, Sorocaba, SP. Abstract... 2018. p. 47-47.

    Abstract: Plastic pollution is an internationally recognized problem and an understanding of the behavior of plastic particles in the environment is still under development [1]. In the environment, plastics degrade into microplastics, i.e. fragments and fibers, then fragmented to nanoplastics (NPs) eventually. These microplastic particles range between 1 mm to 5 mm [2], while the definition of NPs is still under debate; different studies have set the upper size limit from 1 nm to 1 mm [3]. Daily discharges of microplastics are estimated in the range of 50,000 up to 15 million particles, whereas no information on NPs discharges is available yet [4]. The present overview highlights the importance of NPs as a contributor to environmental pollution, which are considered emerging pollutants nowadays. NPs are homo- and/or heteroaggregates conformed with colloidal behavior [3]. The presence of these particles has been evidenced in the atmosphere [5], soil and marine environment, that represents an ultimate sink for contamination [6]. According to the International Standard Organization (ISO), a manufactured nanomaterial is intentionally produced for commercial purposes to have specific properties or specific composition, therefore, the NPs cannot be considered as such [3]. Moreover, release and impact on the environment of these particles is still not evident. Though several studies with engineered plastic nanomaterials showed toxicity and sub-lethal effects with consequences not only at organism and population level but on the overall ecosystem [6], are not representatives results [8]. However, current difficulties in sampling, identifying and characterizating nano-sized debris make it hard to assess their occurrence in the environment. Thus, NPs is a recent issue in the scientific community and deserves further attention to establish new remediation technologies.

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  • IPEN-DOC 25919

    GIMILIANI, G.T. ; REDÍGOLO, M.M. ; FORNARI, M.; PARRA, D.F. ; LUGAO, A.B. ; ABESSA, D.M.S.; COTRIM, M.E.B. ; PIRES, M.A.F. . Micro- and nanoplastics in the sediments of the Santos Estuarine System, Brazil. In: WORKSHOP ON ENVIRONMENTAL NANOTECHNOLOGY, 3rd, October 5-8, 2018, Sorocaba, SP. Abstract... 2018. p. 46-46.

    Abstract: Small-scale plastic debris, such as microplastics and nanoplastics has become leading contributors to the pollution of marine and freshwater ecosystems [1]. These particles are derived from plastic degradation and produced intentionally for manufacturing products [2]. Microplastics are fragments and fibers smaller than 5 mm [3], while the definition of nanoplastics is still under debate; different studies have set the upper size limit at either 1000 nm or 100 nm [2]. The changes in the density of floating plastic debris caused by weathering process, biofilm formation and biofouling may result in sedimentation of these particles [3]. The present study investigates the presence of the micro- and nanoplastics in marine and estuarine sediments because these environments are suggested to be long-term sinks for microplastics. This study is the first investigative analysis about the presence of the micro- and nanoplastics on sediments of the Santos Estuarine System (SES), central coast of the São Paulo State, southeastern Brazil. Sediment samples from four sites distributed along in the Bugres River (23º56’49’’S – 46º22’57’’W), a small estuarine inlet located within the SES, were collected using a Van Veen grab sampler. In laboratory, the samples were then sieved with different mesh sizes (including < 63 μm), dried and evaluated for type of polymer by infrared spectroscopy (IR) and quantification of microplastics by visual sorting. IR analyses indicated that polyethylene and polypropylene were the main types of polymers found in fragments. Abundance of microplastics were likely inversely related to the mesh size of the sieve. Thus, the amount of microplastics increases as the size fractions decreases. Values ranged from 19 to 4,700 particles g-1 of sediment for 2 mm, 450 to 1,900.00 particles g-1 for 1 mm, 634 to 7,440 particles g-1 for 500 μm, 447 to 26,520 particles g-1 for 250 μm. The concentration of fibers ranged from 1.24 to 14.75 times higher compared to the concentration of fragments. In addition, the abundance of microplastics for 125, 63 and < 63 μm will be analyzed by thermogravimetric technique. Considering that the largest abundances of microplastics were found in the smallest meshes, it is expected the presence of nanoplastics in the sediment samples. The results of this study revealed relatively high concentrations of microplastics in sediments of the SES, confirming the widespread occurrence of microplastics in the Bugres River.

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  • IPEN-DOC 25918

    JACOVONE, R.M.S. ; SOARES, J.J.S. ; SOUSA, T.S. ; RODRIGUES, D.F.; SILVA, F.R.O. ; GARCIA, R.H.L. ; VICENTE, E.J.; SAKATA, S.K. . Antibacterial activity of graphene oxide/silver nanocomposite synthesized by sustainable process. In: WORKSHOP ON ENVIRONMENTAL NANOTECHNOLOGY, 3rd, October 5-8, 2018, Sorocaba, SP. Abstract... 2018. p. 85-85.

    Abstract: Graphene oxide/silver nanocomposite has excellent antimicrobial properties [1]. The traditional methods of incorporation of metal in graphene oxide usually require toxic reagents or with long periods of reaction and in high temperature [2]. The objective of this study is to develop an innovative and sustainable method of incorporating silver into graphene oxide by electron beam. This methodology does not involve toxic reagents or residues and it is carried out in a short reaction time at room temperature. Dispersed graphene oxide was mixed with silver in the complex form in water- isopropanol solution. The mix was submitted to a dose of radiation varying between 150 and 400 KGy. The nanocomposite GO/Ag characterization was performed by thermogravimetry analysis (TGA), X-ray diffraction (XDR), scanning transmission electron microscope coupled to the energy dispersive X-ray spectrometry (TEM/EDS). The antibacterial activity of GO/Ag was observed against Gram negative, Escherichia coli by plate count method. The viable cells of GO and GO-Ag was determined by plating the inoculum after 4h of exposure to different concentrations of the nanomaterials (10, 50, 100, 200 and 500 μg/mL). The results showed that for 500 μg/mL of GO, inactivation cells were ca of 5,4 %, while for GOAg, the concentration to inactivate all cell were 5 times lower (100 μg/mL). The silver nanoparticles size range from 20 to 50 nm. This work showed that GO/Ag nanocomposites that were widely studied by their antibacterial properties can be produce by ionizing radiation. This is a sustainable method that does not require toxic reagents and does not generate hazardous wastes. The short reaction time of some minutes and the ambient temperature also make the process attractive.

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  • IPEN-DOC 25917

    SANTOS, A. dos ; SOUZA, G.S. ; SANTOS, D.F. ; ANDRADE, D.A. . Subcritical boron experiments in the IPEN/MB-01 reactor. In: EUROPEAN RESEARCH REACTOR CONFERENCE, March 24-28, 2019, Jordan. Proceedings... Brussels, Belgium: European Nuclear Society, 2019.

    Abstract: Macroscopic (APSD and CPSD) and microscopic (Rossi-α) neutron noise experiments were performed in the IPEN/MB-01 reactor in order to measure subcritical reactivities. Subcritical states of up to around -6600 pcm were reached with insertion of boric acid (H3BO3) into the moderator tank. The subcritical kinetic model of Gandini and Salvatores was employed to infer the relative power between two consecutive subcritical cases, the subcritical reactivity (𝜌gen), and the subcriticality index (𝜁). This experimental methodology to measure these parameters was successfully employed in a previous experiment performed in the IPEN/MB-01 reactor. The measured subcritical reactivities are in good agreement for the APSD and Rossi-α cases. However, some drawbacks were found for the CPSD cases due to difficulties in the establishment of the cutoff frequency. The MCNP6.1 calculated subcritical reactivities were in a good agreement to APSD´s and Rossi-α measurement values. The ENDF/B-VII.0 nuclear data library was employed in all cases.

    Palavras-Chave: boron; reactor noise; amplifiers; criticality; subcritical assemblies; ipen-mb-1 reactor; neutrons; research reactors; data processing

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  • IPEN-DOC 25916

    CAVALCANTE, A.K. ; BATISTA, J.G.S. ; MAZIERO, J.S. ; DAMASCENO, K.C. ; ORMENIO, M.B. ; CAVALCANTE, B.K. ; ROGERO, S.O. ; ROGERO, J.R. ; LUGAO, A.B. . Evaluation of the toxicity of gold nanoparticles produced by green nanotechnology in Zebrafish (Danio rerio). In: WORKSHOP ON ENVIRONMENTAL NANOTECHNOLOGY, 3rd, October 5-8, 2018, Sorocaba, SP. Abstract... 2018. p. 28-28.

    Abstract: Gold nanoparticles (AuNPs) of different sizes and shapes have been extensively studied by researchers and laboratories around the world. Several studies have demonstrated the applicability of gold nanoparticles in the treatment and diagnosis of cancer, in the treatment of chronic inflammation, infections, degenerative diseases and autoimmune diseases [1]. The synthesis of AuNPs generally involves reducing agents which present problems related to toxicity. In order to address this issue, metabolites present in various plant extracts have been exploited for the preparation of different nanoparticles. The methods that use phytochemicals to reduce metal ions provide a green approach to nanotechnology, known as green nanotechnology [2]. Researchers have shown that some phytochemicals, such as mangiferin (MGF) and epigallocatechin-gallate (EGCG), in addition to reducing and stabilizing the gold nanoparticles, are able to functionalize them. These molecules have chemical groups that allow binding to overexpressed receptors on some types of tumor cells [3]. The objective of this study was to evaluate the level of toxicity of the gold nanoparticles, reduced and stabilized with epigallocatechin-gallate (EGCG-AuNPs) in Zebrafish embryos (Danio rerio), as an indication of a possible environmental effect. To assess the developmental impact of embryos, organisms were exposed to different dilutions of the EGCG-AuNPs suspension for a 96-hour period according to OECD Protocol 236 (Fish Embryo Acute Toxicity Test-FET). Zebrafish is an established vertebrate model for the study of development, disease and is being increasingly used for both pre-clinical studies and toxicological applications due to a range of favorable traits [4]. EGCG-AuNPs demonstrated toxicity, with organ lethality being less than 33% at all concentrations used. The work provided a contribution on the toxicity of AuNPs synthesized and stabilized with the epigallocatechin-gallate reducing agent and using Zebrafish embryos as an animal.

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  • IPEN-DOC 25915

    SILVA, M.R.M. ; FIM, R.G.T. ; SILVA, S.C. ; CASINI, J.C.S.; WENDHAUSEN, P.A.P.; TAKIISHI, H. . Influence of alloying elements Zr, Nb and Mo on the microstructure and magnetic properties of sintered Pr-Fe-Co-B based permanent magnets. Materials Science Forum, v. 930, p. 440-444, 2018. DOI: 10.4028/www.scientific.net/MSF.930.440

    Abstract: The addition of alloying elements on rare-earth permanent magnets is one of the methods used to improve the magnetic properties. This present work evaluates the influence of alloying elements such as Zr, Nb and Mo on the microstructure and magnetic properties of sintered Pr-FeCo- B based permanent magnets. The permanent magnets were produced by the conventional powder metallurgy route using powder obtained by hydrogen-decrepitation (HD) method from as cast alloys. In order to produce the magnet Pr16Fe66,9Co10,7B5,7Cu0,7 without alloying elements the mixture of alloys method was employed, mixing two compositions: Pr20Fe73B5Cu2 (33% w.t) and Pr14Fe64Co16B6 (67% w.t). With the purpose of evaluating the influence of the alloying elements, the Pr14Fe64Co16B6X0,1 (where X= Zr, Nb or Mo) (67% w.t) alloy was employed. The characterization of the alloys and the magnets was carried out using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDXS) and the magnetic properties were measured using a permeameter. The magnet without any additions presented the highest intrinsic coercivity (0iHc = 748 KA.m-1) while the magnet with Nb addition presented higher remanence (Br = 1,04 T). The magnet with Zr addition presented the highest maximum energy product (BHmáx = 144 KJ.m-3), and the magnet with Mo addition showed the highest squareness factor (SF = 0,73).

    Palavras-Chave: rare earths; permanent magnets; alloys; magnets; magnetic properties; zirconium; niobium; molybdenum

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  • IPEN-DOC 25914

    FIM, R.G.T. ; SILVA, M.R.M. ; SILVA, S.C. ; CASINI, J.C.S.; WENDHAUSEN, P.A.P.; TAKIISHI, H. . Influence of milling time on magnetic properties and microstructure of sintered Nd-Fe-B based permanent magnets. Materials Science Forum, v. 930, p. 445-448, 2018. DOI: 10.4028/www.scientific.net/MSF.930.445

    Abstract: In this paper, the effect of the grain size on sintered Nd-Fe-B based permanent magnets was investigated. In order, the magnets were produced by different milling times at 200 rpm and then vacuum sintered at 1373 K for 60 minutes followed by cooling outside the furnace. The magnets either produced by lower and higher milling times (30 and 75 minutes) exhibited lower remanence and coercivity, due the inhomogeneous distribution of the grain sizes. The magnet produced by intermediary milling time (45 minutes) exhibited the highest properties among all samples, with remanence of 1.06 T, coercivity of 891.3 KA.m-1, maximum energy product of 211 KJ.m3 and a squareness factor equal 0.92.

    Palavras-Chave: neodymium; magnets; permanent magnets; microstructure; milling; magnetic properties; demagnetization

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  • IPEN-DOC 25913

    STEFANI, GIOVANNI L. de ; MOREIRA, JOÃO M. de L.; MAIORINO, JOSE R.. Cálculos neutrônicos do núcleo do reator AP1000. In: SEMANA DE ENGENHARIA NUCLEAR E CIÊNCIAS DAS RADIAÇÕES, 4., 6-8 de novembro, 2018, Belo Horizonte, MG. Anais... Belo Horizonte: Escola de Engenharia, Universidade Federal de Minas Gerais, 2018. p. 634-642.

    Abstract: O presente trabalho trata da realização de cálculos de validação para modelagem de núcleo de um reator PWR utilizando o código SERPENT. O reator estudado em questão foi o AP1000, da Westinghouse. O estudo foi voltado ao primeiro ciclo do reator AP1000, de maneira a ser realizada uma comparação entre os valores reportados de k∞ para os elementos combustíveis em condição de potência zero frio com uma discrepância de 0,25%. Foram obtidos resultados compatíveis para cálculos de burnup referentes à curva do valor de concentração de boro, apesar do uso de distribuições uniformes de temperatura na modelagem. Além disso, também foram discutidos os efeitos de sombreamento entre os venenos queimáveis (IFBA e Pyrex) e barras de controle que são, juntamente com o boro solúvel, os meios de controle ao longo do primeiro ciclo. Notou-se que a presença de 9 barras de Pyrex em um elemento combustível diminuiu a reatividade média de uma barra de IFBA de 147 pcm para 33 pcm; e a presença de 28 barras de IFBA em um elemento combustível diminuiu a reatividade média de uma barra de Pyrex de 631 pcm para 277 pcm. O valor de reatividade de uma barra de controle negra reduz em cerca de 20% quando 28 barras de IFBA são inseridas no elemento combustível. Dessa forma os resultados mostram que esta versão do código SERPENT pode ser usada para projetar estudos de núcleos de reatores heterogêneos.

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  • IPEN-DOC 25912

    CARVALHO, GLAUBER M. de ; SEMMLER, RENATO ; MENEZES, MARIO O. de . Repositório semântico de dados de análise por ativação neutrônica: uma proposta para eScience. In: SANTOS, ISRAEL F. dos (Org.); SAMPAIO, PAULO N.M. (Org.) WORKSHOP LATINO-AMERICANO DE TRABALHOS EM ANDAMENTO EM COMPUTAÇÃO, 1., 1-5 de outubro, 2018, São Paulo, SP. Anais... São Paulo: Sociedade Brasileira de Computação, 2018. p. 135-140.

    Abstract: Scientific Data Repositories are being made available each time more often, in a search for more transparency for scientific research and its results, making, in this way, possible to validate, reproduce and reuse the data in other studies. In this work, we present the ongoing research, part of a master dissertation, being developed at IPEN-CNEN/SP, seeking to build a semantic repository for Neutron Activation Analysis research data. The study began with the ontology construction and some of the preliminar results of this phase are presented.

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  • IPEN-DOC 25911

    MORAIS, HENRIQUE M.; ROCHA, KAIO R.; TEIXEIRA, LETICIA dos S.; COSTA, MATHEUS F.; SAVOINE, MARCIA M. ; MENEZES, MARIO O. de . Caracterização de testbed em WSN e IoT na reserva indígena no norte do Tocantins. In: SANTOS, ISRAEL F. dos (Org.); SAMPAIO, PAULO N.M. (Org.) WORKSHOP LATINO-AMERICANO DE TRABALHOS EM ANDAMENTO EM COMPUTAÇÃO, 1., 1-5 de outubro, 2018, São Paulo, SP. Anais... São Paulo: Sociedade Brasileira de Computação, 2018. p. 11-16.

    Abstract: The use of a WSN with IoT devices in a critical scenario makes it relevant to perform tests to presume the behavior of the elements of a network in order to optimize its application. This work will present an experiment performed in the FIT IoT-Lab testbed platform, characterizing the Xambioá indigenous reservation, located in the northern region in the state of Tocantins, as an application scenario.

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  • IPEN-DOC 25910

    CARVALHO, G.D.; SILVA, V.C.; HAFFNER, F.; SARTORI, C.A.F. ; LEBENSZTAJN, L.; KRAHENBUHL, L.. Modeling of a metamaterial in the FEA of a contactless transcutaneous energy transfer device. In: SIMPÓSIO BRASILEIRO DE MICRO-ONDAS E OPTOELETRÔNICA, 18.; CONGRESSO BRASILEIRO DE ELETROMAGNETISMO, 13., 12-15 de agosto, 2018, Santa Rita do Sapucaí, MG. Proceedings... 2018. p. 1-5.

    Abstract: Metamaterials are difficult to deal with in computational electromagnetic modelling, e.g. finite element analysis. The reason is the prohibitive discretization refinement needed to account for their actual electromagnetic field distribution profile, within the frequency range used in contactless energy transfer devices. We propose an approach to simplify the modeling of a metamaterial in finite element simulations and present an analysis of its impact in the evaluation of the magnetic field distribution in the vicinity of the metamaterial.

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  • IPEN-DOC 25909

    ZAMBONI, C.B. ; SOUZA, G.O. ; ALVARENGA, A.M. ; GIOVANNI, D.N.S. ; AZEVEDO, M.R.; KONSTANTYNER, T.. Detection of ions by XRF for use in the neonatal clinic. In: BRAZILIAN MEETING ON NUCLEAR PHYSICS, 41th, September 2-6, 2018, Maresias, SP. Abstract... São Paulo: Sociedade Brasileira de Física, 2018. p. 1-1.

    Abstract: In this investigation we intend to introduce bene¯ts to clinical practice in children, especially newborns and premature infants using an alternative procedure based on X-ray °uorescence technology (XRF). The establish- ment of alternative method, focusing on the use of small amounts of blood (a drop) for ions dosage, contributes with actions to humanize health care with minimal su®ering in the sense of adding another alternative for labo- ratory analysis in the pediatric practice. The dimension of this problem can be evaluated when a 3 kg newborn is considered to have between 280 mL and 300 mL of blood, while a preterm of 1 kg is in the range of 180 - 200 mL. As a result, blood collections for laboratory and functional tests in pediatric practice are the main causes of transfusions in infants, especially premature babies, depending on the dysfunction or treatment the child may need two to three collections per day. Based on these facts, the objective of this work is to analyze blood of newborns, concomitant with the traditional collection ("foot test"). The Ca, Cl, Fe and K dosage in blood samples of were determined using XRF technique. The blood samples came from the nursery of the Hospital of Itapecirica da Serra (S~ao Paulo city, Brazil). The X-Ray Fluorescence analysis was performed using X-Ray Spectrometer (X-123 SDD model - Amptek). The XRF analytical technique showed to be appropriate o®ering a new contribution to the neonatal clinic with actions to humanize health care, guaranteeing diagnostic accuracy with minimal su®ering and exposure to risks in the pediatric practice.

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  • IPEN-DOC 25908

    SILVA, PAULO S.C. da ; ZAHN, GUILHERME S. ; CARVALHO, RICARDO N. de ; GENEZINI, FREDERICO A. . Gamma ray spectroscopy studies on low and intermediate level radioactive waste from Angra-1 nuclear power plant. In: BRAZILIAN MEETING ON NUCLEAR PHYSICS, 41th, September 2-6, 2018, Maresias, SP. Abstract... São Paulo: Sociedade Brasileira de Física, 2018. p. 1-1.

    Abstract: The determination of the radionuclide composition of low - and intermediate - level radioactive waste is of paramount importance for the design and implementation of Brazil`s planned radioactive waste repository. While there is some knowledge of the radionuclides expected to be present, the exact activity values in each of the waste bins are not determined with su±cient precision, so theres an ongoing e®ort to analyze the composition of this waste and make the radioactive inventory of the bins containt, which comprises several institutions and laboratories. In the present work the gamma - ray spectroscopy of samples of resin, ¯lters and evaporator concentrate from Angra 1 nuclear power plant have been studied. Small aliquots (» 500 mg) of the distinct samples were stored in glass vials and gamma- counted in a characterized high resolution germanium detector. In order to determine the best counting time, these aliquots were counted for 24h (real - time), with the spectroscopy results saved after each full hour of counting. The resulting twenty four spectra were then analyzed with Canberras Genie - 2000 software, using ISOCS e±ciency correction tool. The results for each sample were then compared to determine the required counting time for each of the radioisotopes of interest.

    Palavras-Chave: low-level radioactive wastes; gamma spectroscopy; nuclear power plants; angra-1 reactor; gasers; radioactive wastes; waste management

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  • IPEN-DOC 25907

    LEÃO, ANICARINE R. ; ZAMBONI, CIBELE B. ; SILVA, DALTON G.N. da ; MENDONÇA, RONALDO Z.; SIMONS, SIMONE M.. Alternative for the quality control of antivenom production proposed by Lonomia obliqua caterpillars using analytic techniques. In: BRAZILIAN MEETING ON NUCLEAR PHYSICS, 41th, September 2-6, 2018, Maresias, SP. Abstract... São Paulo: Sociedade Brasileira de Física, 2018. p. 1-1.

    Abstract: The caterpillars Lonomia obliqua Walker (L. obliqua) species, commonly found in southern Brazil, is very poisonous and can cause severe damage in human (haemorrhagic e®ects) after the contact that can lead to death [1]. The ¯rst case of poisoning (registered in Brazil) occurred in 1989 and the average number of accidents is closer to 500/year [2]. Nowadays, the Butantan Institute (Research Center at S~ao Paulo city, Brazil) is active in the production of this antiveneom in Latin America; it is the only producer of antilonomic serum. However, in the last two years, this caterpillar has been found in other regions due, mainly, to the expansion and destruction of natural ecosystems provide their growth in all regions of the country. To ensure that the antivenom produced (considering the di®erent origins) can be used for the manufacture of unaltered antilonomic serum, it is necessary to standardize this antidote. We intend to standardize the serum obtained from di®erent regions of origin using X-Ray Fluorescence (XRF). The experimental conditions using the compact XRF spectrometers (X-123SDD, Amptek) were optimized. The results will be compared and validated with INAA analysis.

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  • IPEN-DOC 25906

    LEAL, LUIS G.M. ; ZAMBONI, C.B. ; MENDONÇA, RONALDO Z.; SIMONS, SIMONE M.; NASCIMENTO, ROBERTO M. do. Characterization of the extract of propolis produced by Scaptotrigona aff. Postiça bee from Brazil using NAA and XRF techniques. In: BRAZILIAN MEETING ON NUCLEAR PHYSICS, 41th, September 2-6, 2018, Maresias, SP. Abstract... São Paulo: Sociedade Brasileira de Física, 2018. p. 1-1.

    Abstract: The objective of this investigation was to perform a multielemental characterization of the extract of the propolis produced by Scaptotrigona a® Posti»ca Bee (\tubi") from Barra do Corda (MA-Brasil). The extract produced by this propolis have several medical applications: it is used in the healing of wounds with an in°ammatory process, in treatment of prostate tumors and, it has activity against herpes and rubella virus [1-3]. Two analytic techniques were applied for investigation: Neutron Activation Analysis (NAA) and X Ray Fluorescence (XRF). The neutron activation measurements were performed using the IEA-R1 nuclear reactor at IPEN - CNEN/SP and XRF data were obtained using a compact X- Ray spectrometer (X-123 SDD, Amptek) constituted by a Silicon detector coupled a mini X-ray tube (Ag). Direct analysis using EDXRF was compared with INAA procedure to evaluate the e®ect matrix and the results were satisfactory. These data increase the knowledge of the components and can introduce improvements in the production these extracts, mainly as regards to toxicity and nutritional composition.

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  • IPEN-DOC 25905

    CAVALCANTI, H. de S. ; MIURA, VIVIANI M. ; ZAMBONI, CIBELE B. ; SILVA, DALTON G.N. da ; AZEVEDO, MARIA R.. The potassium reference value in blood in inhabitants of Brazil using EDXRF technique. In: BRAZILIAN MEETING ON NUCLEAR PHYSICS, 41th, September 2-6, 2018, Maresias, SP. Abstract... São Paulo: Sociedade Brasileira de Física, 2018. p. 1-1.

    Abstract: In this investigation, we intend to determine potassium levels in human blood aiming to study in more details the common de¯ciencies in Brazilian population helping their diagnostic well as to facilitate the interpretation of data deriving from clinical practice. The potassium takes part in the human being metabolism and it is very important for preservation of the osmotic and acid-base equilibria of human °uids, so its variations are generally associated to pathological processes. The objective of this study is the establishment of reliable potassium reference value in blood, using EDXRF technique, with emphasis on the statistical treatment. The samples came from Blood Banks from di®erent parts of Brazil. The biological samples were obtained from a select healthy group (male and female blood donors), following the procedure conventionally establish for blood donation. The in°uence of sex and age was evaluated considering several range for age (18-20, 21-30, 31-40, 41-50, 3 51 years). The result is presented following a descriptive statistics procedure, which includes the evaluation of mean, standard deviation, median and mode. This statistical treatment make possible the comparison with data derived for di®erent population groups. These results show small di®erences when a comparison is performed in function of age and sex emphasizing the necessity to adopt ranges.

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  • IPEN-DOC 25898

    GARCIA, VANESSA S.G. ; PEREIRA, MARIA C. ; ROSA, JORGE M. ; BORRELY, SUELI I. . Estudo sobre toxicidade do efluente e do consumo hídrico e energético no tingimento de poliamida. In: CONGRESSO NACIONAL DE MEIO AMBIENTE, 15., 25-28 de setembro, 2018, Poços de Caldas, MG. Resumo expandido... Poços de Caldas: GSC Eventos Especiais, 2018. p. 1-4.

    Abstract: O estudo concentrou-se na determinação do consumo hídrico e energético durante o tingimento da poliamida, bem como na avaliação do efeito tóxico do efluente para o microcurstáceo Daphnia similis. O processo de tingimento necessário para o tingimento de um quilograma de substrato consome energia suficiente para um banho de nove horas de duração utilizando-se um chuveiro convencional (4000 W). O efluente pode ser considerado como muito tóxico tendo em vista que a CE50 foi 0,61 ± 0,21 (%, v/v) após 48 horas de exposição. Conforme orientação da Resolução CONAMA 430/2011 o efluente deve ser tratado em nível tal que não induza toxicidade quando lançado no corpo receptor. Busca por tecnologias que permitam redução de toxicidade, reuso de efluentes e otimização de processos de tingimento, são de extrema necessidade dentro desta atividade industrial.

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  • IPEN-DOC 25897

    COUTO, C.P. ; GOMES, M.P. ; COSTA, P.D.O. ; COLOSIO, M.A.; POLITANO, R. ; ROSSI, J.L. . Characterization of PHS coating layer using GDOES technique. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo: Blucher, 2017. DOI: 10.5151/phypro-viii-efa-08

    Abstract: O objetivo do estudo foi analisar o perfil de composição química do revestimento Al-Si em aços PHS, por meio da técnica de GDOES. Devido às elevadas temperatura no processo de estampagem a quente ocorre à difusão dos elementos do revestimento e do substrato. Os resultados revelaram que na amostra como recebida, o revestimento apresenta grandes porcentagens de alumínio, silício e oxigênio, que se difundem e diminuem de concentração em direção ao substrato, enquanto que a porcentagem de ferro aumenta. Os resultados das amostras tratadas termicamente em laboratório e do produto final são muito similares, o que indica que o tratamento térmico realizado em laboratório simula corretamente o processo térmico da estampagem industrial. O revestimento é formado por alumínio e ferro, que variam uniformemente até atingir o substrato onde a porcentagem de alumínio diminui em relação à de ferro. A camada revestida também é composta por oxigênio e silício que se difundem em direção ao substrato, onde a porcentagem de oxigênio diminui gradativamente e a de silício não se altera. Os resultados de GDOES mostraram as alterações que ocorrem na camada revestida do aço PHS, e evidenciaram que após o processo de estampagem a quente podem ser formados óxidos e fases compostas por Al-Fe ou Al-Fe-Si.

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  • IPEN-DOC 25896

    NISTI, M.B. ; SAUEIA, C.H.R. ; CASTILHO, B. ; MAZZILLI, B.P. . Assessment of Sr-90, Cs-137, natural radionuclides and metals in marine fish species consumed in the city of São Paulo - Brazil. In: INTERNATIONAL SYMPOSIUM ON NUCLEAR AND ENVIRONMENTAL RADIOCHEMICAL ANALYSIS, 13th, September 17-20, 2018, Cambridge, UK. Abstract... Royal Society of Chemistry, 2018. p. 68-68.

    Abstract: The study of artificial radionuclides dispersion into the environment is very important to control the nuclear waste discharges, nuclear accidents and nuclear weapons testing. The accident in Fukushima Daiichi Nuclear Power Plant on 11 March 2011, released several radionuclides in the marine environment by aerial deposition and liquid discharge, with various level of radioactivity. The 90Sr and 137Cs were two of the elements released into the environment, 90Sr is estimated that its atmospheric releases ranged from 3.3.10-3 to 0.14 PBq, and 137Cs is estimated that its atmospheric releases ranged from 7 to 20 PBq. The 90Sr and 137Cs are produced by nuclear fission with a physical half-life of 28.79 years and 30.15 years, respectively. The natural radionuclides (210Pb, 226Ra and 228Ra) were determined to check the reference values. The concentrations of metals were determined to compare with the values of the maximum limits of the regulation. The aim of this study is to quantify the concentration of the 90Sr, 137Cs, natural radionuclides and metals in the muscles of marine fish species most consumed in São Paulo city. The species and scientific names of the fishes analyzed were bluefish (pomatomus saltatrix), croaker (micropogonias furnieri), hake (merluccius merluccius), Smooth-hounds nei (Mustelus spp.), sardine (sardinella brasiliensis) and mullet (Mugil brasiliensis). The determination of 90Sr by liquid scintillation counting (LSC) measurement was performed using a 1220 Quantulus™ Ultra Low Level Liquid Scintillation Spectrometer. The 137Cs and natural radionuclides were measured by gamma spectrometry, using an HPGe detector. The metals concentration was determined by instrumental neutron activation analysis (INAA). The results obtained in this study can be used to ensure the quality of the fish consumed in the São Paulo city.

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  • IPEN-DOC 25895

    SAUEIA, C.H.R. ; NISTI, M.B. ; MAZZILLI, B.P. . Precision and accuracy of the methodology for the determination of Pb-210 by LSC and Po-210 by alpha spectrometry using a Sr-Spec resin. In: INTERNATIONAL SYMPOSIUM ON NUCLEAR AND ENVIRONMENTAL RADIOCHEMICAL ANALYSIS, 13th, September 17-20, 2018, Cambridge, UK. Abstract... Royal Society of Chemistry, 2018. p. 65-65.

    Abstract: Pb-210 and Po-210 were important from the radiation protection and environmental protection point of view, due to its high toxicity. It is part of the U-238 natural series, formed by decay of the Rn-222 gas; Pb-210 has a half-live of 22.3 years and emission beta particles with 16.5 keV (80.2%) and 63.0 keV (19.8%); and Po-210 has a half-live of 138.4 days and emission alpha particle with 5.3 MeV. The methodology for the Pb-210 and Po-210 determination is based on the purification and concentration of the radionuclides using a Sr-Spec resin from EICHRON and performed by Liquid Scintillation Counting (LSC) and Alpha Spectrometry, respectively. The sample solution was loaded onto the Sr resin column preconditioned in advance with 100 mL of 2M HCl. Lead and polonium were retained , Po-210 was stripped with 60 mL of 6M HNO3 and Pb was eluted with 60 mL of 6M HCl. Po was spontaneously deposited on a silver disc and counted on an alpha spectrometer for 80,000 seconds. The Pb solution was evaporated three times with 5 mL portions of 65% HNO3 and the final residue was dissolved in 10 mL of 1M HNO3. Pb was precipitated as Pb-oxalate, which was dried and weighed to calculate the chemical recovery using the gravimetric method. The precipitate was quantitatively transferred into a liquid scintillation vial and 1 mL of 1M HNO3 was added to dissolve the precipitate. The solution was mixed with 15 mL of Hisafe III scintillation solution. The final solution was counted on a 1220 Quantulus™ Ultra Low Level Liquid Scintillation Spectrometer for 24,000 seconds. In this paper, evaluates the accuracy and precision of the methodology of Pb-210 by LSC and Po-210 by alpha spectrometry using a separation technique with resin Sr-Spec was performed.

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  • IPEN-DOC 25894

    ROVANI, S. ; SANTOS, J.J.; CORIO, P.; FUNGARO, D.A. . Low cost silica nanoparticles biosorbent obtained from sugarcane waste ash: characterization and adsorption study of methylene blue dye. In: ENCONTRO BRASILEIRO SOBRE ADSORCAO, 12., 23-25 de abril, 2018, Gramado, RS. Anais... 2018.

    Abstract: Sugarcane waste ash, a Si-rich source, is generated in large quantity and can create a serious disposal problem. The production of silica nanoparticles (silicaNPs) from sugarcane waste ash varying ash:NaOH mass ratio was evaluate. The samples were characterized by total X-ray fluorescence spectroscopy, SEM, TEM, XRD, surface area and pore distribution, FTIR and TGA and applied as biosorbent for methylene blue dye removal. The yield of silicaNPs extraction remained constant from ash:NaOH mass ratio 1:1.5. Si content was 77.32 wt.% and 94.89wt. % for sugarcane waste ash and silicaNP 1:1.5, respectively. SilicaNP 1:1.5 presented particles smaller than 100 nm, surface area of 63 m2 g-1 and adsorption capacity of 37 mg g-1 for methylene blue. The results indicate that was possible to obtain a biosorbent, from a renewable source, with low cost and with easy and fast synthesis procedure.

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  • IPEN-DOC 25893

    CARVALHO, PATRICIA R. ; MUNITA, CASIMIRO S. . Estudos arqueométricos de cerâmicas sul-americanas. Revista da Universidade Ibirapuera, v. 16, p. 52-62, 2018.

    Abstract: As análises realizadas neste trabalho têm como objetivo contribuir com a discussão sobre os materiais utilizados na fabricação, a tecnologia de produção e a idade de objetos cerâmicos de antigas civilizações sul- -americanas. Para isso, quarenta e seis fragmentos de cerâmica de cinco sítios arqueológicos de Cusco, Peru, foram analisados utilizando INAA para determinar a fração de massa de 20 elementos químicos (Na, K, La, Nd, Sm, Yb, Lu, U, Sc, Cr, Fe, Co, Rb, Cs, Ce, Eu, Tb, Hf, Ta e Th). Três métodos estatísticos multivariados, análise de agrupamentos, análise discriminante e gráfico bivariado, foram aplicados no conjunto de dados. Pela análise de agrupamentos encontraram-se três grupos de amostas de composição química similar, os quais, por meio da análise discriminante e do gráfico bivariado, foi possível confirmar que foram classificados corretamente. Os resultados mostram que as amostras foram fabricadas com 3 diferentes fontes de matéria- -prima. O estudo da datação por TL mostrou que os três grupos de amostras estão de acordo com os três períodos do Império Inca. Ademais, o estudo da temperatura de queima realizada pela EPR mostrou que era inferior a 600 °C.

    Palavras-Chave: ceramics; neutron activation analysis; archaeological sites; cultural objects; historical aspects; electron spin resonance; peru; andes; thermoluminescence; x-ray diffraction

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  • IPEN-DOC 25880

    BORDON, ISABELLA C.; CAMPOS, BRUNO G. de; GUSSO‑CHOUERI, PALOMA K.; MIYAI, CAIO A.; ARAUJO, GIULIANA S. de; EMERENCIANO, ANDREWS K.; SILVA, JOSE R.M.C. da; COTRIM, MARYCEL E.B. ; FAVARO, DEBORAH I.T. ; ABESSA, DENIS M. de S.. Improvements in metal exposure assays: artificial food to assess bioaccumulation in the blue crab Callinectes danae Smith, 1869 (Crustacea, Decapoda, Portunidae). International Journal of Environmental Research, v. 13, n. 2, p. 431-434, 2019. DOI: 10.1007/s41742-019-00170-3

    Abstract: This technical note aims to report, in detail, the development, suitability and analytical validation of an artificial food to assess metal bioaccumulation in the blue crab Callinectes danae after metal exposure assays. For this purpose, lead (Pb) was chosen as the metal of interest. First, a non-contaminated artificial food was prepared by mixing commercial shrimps and agarose. The food was then offered on alternate days to two groups of crabs for 7 and 14 days, respectively. After confirming that this food was well-accepted by crabs, analytical procedures were performed to confirm that Pb added to the mixture would remain in the artificial food. For this purpose, two foods containing Pb at concentrations of 0.5 and 2.0 μg g− 1 were prepared by adding aliquots of an ultrapure Pb standard solution to the mixture. Samples of each food were subjected to an acid extraction and Pb concentrations were determined by a GF-AAS. Pb recoveries in both contaminated foods were > 90%. Subsequently, another experiment was performed, and two groups of crabs were fed with contaminated artificial foods (0.5 and 2.0 μg g− 1 of Pb) during 7 and 14 days, respectively. The observed acceptance of these foods by crabs at both Pb concentrations was of 100%.

    Palavras-Chave: crabs; sampling; lead; contamination; food; metals

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  • IPEN-DOC 25790

    SIMÕES, MARTA F.; MAIORANO, ALFREDO E.; SANTOS, JONAS G. dos; PEIXOTO, LUCIANA; SOUZA, RODRIGO F.B. de ; OLIVEIRA NETO, ALMIR ; BRITO, ANTONIO G.; OTTONI, CRISTIANE A.. Microbial fuel cell‑induced production of fungal laccase to degrade the anthraquinone dye Remazol Brilliant Blue R. Environmental Chemistry Letters, v. 17, n. 3, p. 1413-1420, 2019. DOI: 10.1007/s10311-019-00876-y

    Abstract: The anthraquinone dye Remazol Brilliant Blue R is largely used in the textile industry. However, its removal from wastewaters is costly and complex. Many methods have been tested to solve this ecological problem, but there is still a need for efficient methods. We propose here an alternative use of a two-chambered microbial fuel cell (MFC), fuelled with domestic wastewater in the anodic chamber, to degrade a simulated textile dye effluent made of Remazol Brilliant Blue R inoculated with an immobilised fungal strain, Pleurotus ostreatus URM 4809, as a laccase producer, in the cathodic chamber. The MFC showed continuous synthesis of laccase in the cathodic chamber, which, in turn, promoted the rapid decolourisation, of more than 86% of the textile dye effluent. The yield was further increased by the addition of glycerol. Electrochemical monitoring also indicated an increase in power density and current density. After 20 days of MFC operation, 62.1% of organic matter was removed in the anodic compartment, thus leaving the effluent with a much lower toxicity.

    Palavras-Chave: biofuels; fuel cells; dyes; waste water; fungi; water pollution; toxicity; textile industry

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  • IPEN-DOC 25892

    VILLANI, D. ; CAMPOS, L.L. . Aplicação da técnica de Luminescência Opticamente Estimulada (OSL) na monitoração de área de uma sala de exame de mamografia. In: NEVES, LUIS (Coord.). Proteção contra radiações na comunidade dos países de língua portuguesa. Coimbra, Portugal: Imprensa da Universidade de Coimbra, 2018. p. 139-147, DOI: 10.14195/978-989-26-1602-5

    Abstract: O objetivo deste trabalho é avaliar o desempenho dos dosímetros OSL nanoDot™ para a monitoração de área de uma sala de mamografia. Os testes foram realizados primeiramente em laboratório, para caracterização dosimétrica, avaliação da repetibilidade e estabilidade do sistema utilizado e, posteriormente, na sala de mamografia para avaliar as doses dispersas no ambiente, bem como a dose de entrada na pele. Os resultados mostraram que os nanoDots™ apresentam boa repetibilidade e estabilidade tanto nos testes laboratoriais como nos de campo, o que permite sua aplicação na dosimetria de área.

    Palavras-Chave: dosimetry; luminescence; mammary glands; diagnosis; diagnostic techniques

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  • IPEN-DOC 25891

    BRAVIM, A. ; SAKURABA, R.K.; CAMPOS, L.L. . Avaliação de dosímetros OSL na determinação de curvas de isodose de uma simulação de planejamento de tratamento de vértebra com proteção da medula espinhal utilizando VMAT. In: NEVES, LUIS (Coord.). Proteção contra radiações na comunidade dos países de língua portuguesa. Coimbra, Portugal: Imprensa da Universidade de Coimbra, 2018. p. 111-120, DOI: 10.14195/978-989-26-1602-5

    Abstract: O objetivo deste trabalho foi avaliar a aplicabilidade de dosímetros e microdosimetros OSL de LiF:Mg,Ti (TLD-100) na determinação das curvas de isodose em planejamentos utilizando a técnica de VMAT. Foi simulado um planejamento de tratamento de vértebra com proteção da medula espinhal em que a dose média absorvida obtida através dos dosímetros OSL apresentou uma variação máxima de 3,85% em relação aos valores calculados pelo sistema de planejamento Eclipse 11.0. A variação entre o intervalo de dose obtido com o emprego dos dosímetros OSL e fornecido pelo Eclipse 11.0 está de acordo com os limites aceitáveis para a área da radioterapia. Observou-se que, por serem de menor tamanho, os microdosímetros de LiF:Mg,Ti apresentam uma menor probabilidade de estarem posicionados em mais de uma curva de isodose ao mesmo tempo no planejamento. Sendo assim, apresentaram os melhores resultados.

    Palavras-Chave: isodose curves; dosimetry; lithium fluorides; magnesium; neoplasms; phantoms; planning; radiation dose distributions; radiotherapy; spinal cord

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  • IPEN-DOC 25890

    BRESSANE, R.O. ; VILLANI, D. ; RODRIGUES JUNIOR, O. ; CAMPOS, L.L. . Estudo comparativo de sensibilidade entre os dosímetros fricke xilenol gel e alanina gel. In: NEVES, LUIS (Coord.). Proteção contra radiações na comunidade dos países de língua portuguesa. Coimbra, Portugal: Imprensa da Universidade de Coimbra, 2018. p. 85-93, DOI: 10.14195/978-989-26-1602-5

    Abstract: Fricke Xilenol Gel (FXG) é um dosímetro químico bem conhecido e caracterizado. Neste trabalho, foi adicionada alanina ao FXG a fim de obter melhora na sensibilidade. A comparação entre os dois dosímetros permitiu verificar maior estabilidade no gel devido à presença da alanina e aumento do intervalo de linearidade da resposta óptica: de 1 a 30 Gy para 5 a 50 Gy. Foi possível verificar, também, que a variação de cor das amostras após a irradiação é característica de cada tipo de dosímetro e que a sensibilidade do dosímetro com alanina é maior utilizando-se 0,2 mM de alaranjado de xilenol.

    Palavras-Chave: xylenols; gels; alanines; comparative evaluations

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  • IPEN-DOC 25889

    VENEZIANI, G.R. ; RODRIGUES JUNIOR, ORLANDO ; SAKURABA, R.K.; CAMPOS, L.L. . Desenvolvimento de simulador aplicados a radiodiagnostico e radioterapia utilizando impressora 3D. In: NEVES, LUIS (Coord.). Proteção contra radiações na comunidade dos países de língua portuguesa. Coimbra, Portugal: Imprensa da Universidade de Coimbra, 2018. p. 77-83, DOI: 10.14195/978-989-26-1602-5

    Abstract: Nesse trabalho foi avaliada a viabilidade do uso de impressora 3D (FDM) e materiais tecido equivalentes para o desenvolvimento de simuladores para serem aplicados em radioterapia e/ou diagnóstico. Os resultados avaliados por CT foram bastante promissores e abrem caminho para o desenvolvimento de simuladores personalizados e de baixo custo.

    Palavras-Chave: radiotherapy; biomedical radiography; phantoms; 3d printing; simulators; tissue-equivalent materials

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  • IPEN-DOC 25888

    VALERIANO, C. ; VENEZIANI, G. ; JUNIOR, O. ; VIVOLO, V. ; SANTOS, W.S.; CAMPOS, L.L. . Determinação dos coeficientes de atenuação para feixes de raios X diagnóstico do PLA e do ABS impressos: uma abordagem por simulação com MCNP5. In: NEVES, LUIS (Coord.). Proteção contra radiações na comunidade dos países de língua portuguesa. Coimbra, Portugal: Imprensa da Universidade de Coimbra, 2018. p. 69-76, DOI: 10.14195/978-989-26-1602-5

    Abstract: Modelos 3D de estruturas anatômicas podem ser obtidos por meio de técnicas de imageamento médico (ressonância magnética e tomografia computadorizada). 70 Variando os materiais (por exemplo poliuretano e resina epóxi) utilizados em sua composição, é possível obter o contraste radiográfico ou a equivalência ao tecido desejado. A produção de objetos simuladores para pacientes específicos precisa preencher requisitos como a acurácia geométrica com a anatomia do individuo, a equivalência ao tecido, de modo que possam ser realizar medidas utilizáveis, e não ser susceptível aos efeitos da radiação. A utilização de impressoras 3D é uma forma rápida de construção de objetos complexos, dessa forma é justificável estudar a viabilidade da impressão 3D para desenvolver objetos simuladores. Baseado nesse cenário, o presente trabalho tem como objetivo avaliar a simulação desenvolvida, utilizando MCNP5, como ferramenta para a obtenção dos coeficientes de atenuação das placas feitas com material de impressora 3D.

    Palavras-Chave: attenuation; monte carlo method; phantoms; validation; computerized simulation; anatomy; plates

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  • IPEN-DOC 25887

    CORREA, F. ; SORDI, G. ; LEVY, D.S. . Evolução da filosofia do sistema de limitação de dose e a questão das substituições “superseded”. In: NEVES, LUIS (Coord.). Proteção contra radiações na comunidade dos países de língua portuguesa. Coimbra, Portugal: Imprensa da Universidade de Coimbra, 2018. p. 351-361, DOI: 10.14195/978-989-26-1602-5

    Abstract: O grande avanço da era nuclear mostrou que a filosofia do sistema de limitação de dose proposta pela Comissão Internacional de Proteção Radiológica em 1958 e os Limites Anuais Máximos Permissíveis (LAMP), careciam de mudanças, assim, com a atualização das recomendações surgiu uma nova filosofia, ainda vigente, denominada de Limites Anuais Máximos Admissíveis (LAMA) para que possamos estuda-los separadamente, analisando cuidadosamente como surgiram estas filosofias e como foram evoluindo até as suas últimas publicações. 352 Uma vez que cada nova publicação substituía a anterior, e a ICRP e o Organismo Internacional de Energia atômica (IAEA) firmaram o acordo pelo qual este último adotaria a filosofia proposta pela Comissão, houve a possibilidade que algumas destas informações, algumas valiosas, possam ter se perdido no decorrer da substituição da publicação e ou da edição da norma do IAEA na adoção da filosofia. Estas informações são discutidas e estudadas em profundidade e o seu valor real mostrado, levantando a possibilidade de reintroduzi-las nas futuras publicações.

    Palavras-Chave: annual limit of intake; data compilation; equivalent radiation doses; information systems; international convention on nuclear safety; nuclear data collections; personnel dosimetry; radiation protection; recommendations

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  • IPEN-DOC 25886

    LEVY, D.S. ; SORDI, G.M.A.A. . Education and communication on radiological protection: the potential value of information technologies to improve profess ional skills. In: NEVES, LUIS (Coord.). Proteção contra radiações na comunidade dos países de língua portuguesa. Coimbra, Portugal: Imprensa da Universidade de Coimbra, 2018. p. 313-325, DOI: 10.14195/978-989-26-1602-5

    Abstract: For operational control of exposures to ionizing radiation in any workplace, the International Commission on Radiation Protection (ICRP) recommends establishing a program of operational radiation protection, proportional to the risk, to ensure the effective management of all necessary measures to satisfy the principle of optimization. This project focus on the potential value of Information and Communication Technologies (ICTs) to enhance education and communication on Radiological Protection throughout Brazil. The content includes optimization programs and monitoring policy and techniques, interrelating 314 information currently scattered in several documents, providing Brazilian facilities a complete repository for consultation and information. The content also brings new approaches from some recommendations, presenting some initiatives towards protection and safety. The growing impact of ICTs shall contribute greatly to provide information where it is needed, stimulating development in this large country where it is a huge challenge to ensure access to information to as many people as possible, minimizing costs and optimizing results.

    Palavras-Chave: radiation protection; education; radiation monitoring; information systems

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  • IPEN-DOC 25885

    SILVA, JULIO C.M. da ; LOPES, THIAGO ; OLIVEIRA NETO, ALMIR ; SPINACE, ESTEVAM V. . Electrocatalysts for direct ethanol fuel cells. In: SANTOS, MAURO C. dos (Ed.). Advanced Materials and Systems for Electrochemical Technologies. Hauppauge, NY, USA: Nova Science Publishers, 2018. p. 27-52, cap. 2.

    Abstract: In this chapter, an overview of electro-catalysts for direct ethanol fuel cells based on polymer electrolyte membranes is presented, with special attention given to the alkaline anion exchange membrane-based devices. Considering the anodic reaction, it is evidenced that a substantial effort has been dedicated towards increasing the fuel cell efficiency by developing electrocatalysts with higher catalytic activity. In this sense, palladium is pointed out as a promising substitute to platinum with regards to electrocatalytic activity, price and element availability. Furthermore, palladium-based nanoparticles are pointed out as the electrocatalysts with the highest electrocatalytic activity for ethanol electro-oxidation in alkaline media. Taking into account the support materials for the electrocatalysts nanoparticles, it was possible to observe an evolution in carbon-based materials, first carbon nanotubes overcame the carbon black, where more recently, graphene is addressed as the best support choice for catalysts nanoparticles. Different efforts have been made to improve the properties of the support materials, such as doping with nitrogen or with metal oxides like TiO2, for example. Considering the cathode materials, the main goal is to develop catalysts with enhanced activity to the oxygen reduction reaction as well as tolerance to ethanol molecules that crossover the electrolyte membrane.

    Palavras-Chave: gas chromatography; electrocatalysts; carbon nanotubes; carboxylase; platinum; tin oxides; ethanol; direct ethanol fuel cells

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  • IPEN-DOC 25884

    OTTONI, CRISTIANE A.; SIMÕES, MARTA F.; SANTOS, JONAS G. dos; PEIXOTO, LUCIANA; SOUZA, RODRIGO F.B. de; OLIVEIRA NETO, ALMIR ; BRITO, ANTONIO G. de; MAIORANO, ALFREDO E.. Biotratamento de vinhaça sintética e geração de eletricidade utilizando uma célula a combustível microbiana. In: OLIVEIRA, ANTONELLA C. de (Ed.); SANTOS, ALBERDAN S. (Org.). Avanços Científicos e Tecnológicos em Bioprocessos. Ponta Grossa, PR: Atena Editora, 2018. p. 163-171, cap. 20. DOI: 10.22533/at.ed.475180110

    Abstract: O Brasil é um dos maiores produtores de etanol no mundo, no entanto, durante o processo de obtenção deste combustível, elevadas quantidades de vinhaça são geradas, em média, para cada litro de etanol produzido são gerados 13 litros deste resíduo. A vinhaça possui propriedades físicas e químicas que podem desencadear efeitos nocivos à biota, deste modo, existe um interesse crescente em identificar novas tecnologias para o seu tratamento. A utilização de células a combustível microbianas (CCMs) apresenta um enorme potencial, uma vez que, pode promover simultaneamente o tratamento deste resíduo e a biogeração de energia elétrica, pela conversão da energia química disponível nesses substratos biodegradáveis diretamente em eletricidade, por meio da ação catalítica de bactérias eletrogênicas aderidas ao eletrodo. Neste contexto, o presente estudo avaliou a utilização de uma CCM de câmara dupla no tratamento de vinhaça sintética. Durante a operação deste reator foi detectada uma máxima densidade de potência de 330 mW·m-2 e uma redução na demanda química de oxigênio (DQO) em 58,8% após 28 dias. Diante destes resultados preliminares, a tecnologia CCM pode ser considerada promissora no tratamento da vinhaça, contudo, estudos a respeito da configuração, tipo de inóculo e formas de operação da CCM são necessários para que amplie sua eficiência.

    Palavras-Chave: biofuels; alternative fuels; fuel cells; organic compounds; microorganisms; bacteria; power density; chemical oxygen demand

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  • IPEN-DOC 25883

    FUNGARO, DENISE A. ; IZIDORO, JULIANA C. ; GUILHEN, SABINE N. ; SILVA, KATIA C. ; WANG, SHAOBIN. Synthesis of nanocrystalline zeolite Na-A from coal fly ash and different aluminum sources: application for heavy metals removal. In: GRAY, MIRIAM (Ed.). Coal Fly Ash. Hauppauge, NY, USA: Nova Science Publishers, 2018. p. 1-33, cap. 4.

    Abstract: This chapter describes the synthesis process to obtain zeolite Na-A from coal fly ash via fusion with NaOH followed by hydrothermal reaction. Coal fly ash is a low cost source of both silica and alumina. The molar ratio of SiO2/Al2O3 for zeolite 4A formation was achieved by the addition of sodium aluminate solution or aluminum waste from tertiary industry as aluminum sources. The effects of temperature and time at the fusion step and the hydrothermal reaction time on crystalline products were investigated. The synthesized products were studied for their purity and yield as well as were characterized by different techniques such as Xray powder diffraction (XRD), scanning electron microscopy (SEM) and cation exchange capacity (CEC), among others. Analysis of the properties of the raw materials and the products demonstrates that the by-products can be used to produce a high purity zeolite A. The optimum conditions related to the synthesis was set and the samples were pure, highly crystalline and white. The synthesized zeolites were used for both the removal of Cd (II) and Zn (II) from aqueous solution. The results showed that coal fly ash and aluminum source can be transformed into zeolite A, which is considered as value-added material with adsorption properties.

    Palavras-Chave: synthesis; zeolites; nanocrystals; coal; fly ash

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  • IPEN-DOC 25882

    LINO, JULIANA dos S. ; AQUINO, AFONSO R. de . Análise da evolução das áreas contaminadas no município de São Paulo. In: ANDRADE, DARLY F. (Ed.). Sustentabilidade e Responsabilidade Social em Foco. Belo Horizonte, MG: Editora Poisson, 2019. p. 51-58, v. 12, cap. 4.

    Abstract: O expressivo surgimento de áreas contaminadas ao redor do globo, especificamente em centros urbanos industrializados, é resultado de processos socioeconômicos sem a percepção da relevância das questões ambientais a eles associadas. O uso e a ocupação do solo das cidades se deram sem o conhecimento de parâmetros de proteção e controle ambiental. O solo era visto como um local seguro para a disposição de rejeitos, um local onde o processo de degradação de contaminantes aconteceria naturalmente. Diante da enorme velocidade com que ocorreu o crescimento metropolitano, só tardiamente o poder público se proveu de instrumentos legais para buscar proteção e ordenação no uso do solo. Somente no final do século XX, a questão das áreas contaminadas começou a ser debatida, estando atualmente associada ao tema da revitalização urbana, buscando conferir novo uso sustentável para essas áreas contaminadas com o objetivo de agregá-las ao tecido urbano, estimulando e possibilitando a requalificação urbana. Essa mudança de postura intensificou o reconhecimento de áreas nas quais se desenvolveram atividades potencialmente poluidoras, ocorridas principalmente em regiões densamente povoadas e industrializadas, e sua reutilização, se feita sem a adoção de critérios adequados pode representar um grave risco para a saúde das populações locais. Uma das características da cidade de São Paulo é o seu grande dinamismo e por ter passado por diversos rearranjos espaciais, ao longo das últimas décadas. Devido o caráter dinâmico da cidade e da importância da identificação efetiva das áreas contaminadas, a fim de que estas sejam refuncionalizadas adequadamente, neste trabalho foram estudados os mecanismos que possibilitam a identificação destas áreas na cidade de São Paulo, associado a uma apreciação da sua evolução histórica. O significativo aumento no número de áreas na cidade de São Paulo não deve ser entendido como um fator negativo. O conhecimento real da situação possibilita que a questão seja tratada de forma assertiva. É importante conhecer a dimensão do problema para que a solução desenvolvida abranja todas as suas dimensões.

    Palavras-Chave: environment; pollution; environmental policy; urban areas; environmental degradation; contamination; soils; pollution regulations

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  • IPEN-DOC 25881

    NEVES, EDUARDO G.; MUNITA, CASIMIRO S. ; HAZENFRATZ, ROBERTO; MONGELO, GUILHERME Z.. Ancient exchange networks in the Central Amazon. In: GLASCOCK, MICHAEL D. (Ed.); NEFF, HECTOR (Ed.); VAUGHN, KEVIN J. (Ed.). Ceramics of the Indigenous Cultures of South America. Albuquerque, NM, USA: University of New Mexico Press, 2019. p. 231-239, cap. 22.

    Palavras-Chave: archaeology; archaeological specimens; cultural objects; neutron activation analysis; indigenous peoples; topography; amazon river

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  • IPEN-DOC 25879

    IZIDORO, JULIANA ; FUNGARO, DENISE ; CAMPELLO, FELIPE ; GUILHEN, SABINE . Immobilization agents study of toxic elements in coal ash. In: CASARES, J. (Ed.); PASSERINI, G. (Ed.); PERILLO, G. (Ed.). Environmental Impact IV. Southampton, UK: WIT Press, 2018. p. 387-395, v. 215, (WIT Transactions on Ecology and the Environment). DOI: 10.2495/EID180351

    Abstract: Metal leaching from coal fly ashes into the environment is of a much concern. A series of batch tests were performed to investigate the potential leaching of metals from fly ash modified with organosilane (OS) and quaternary ammonium surfactant (SF). The fly ash was collected at the Figueira Thermal Power Plant, located in the city of Figueira, State of Paraná. Firstly, the influence of ash mass/water volume ratio on the concentration of the elements in the leachates from untreated fly ash was evaluated. Subsequently, the capacities of immobilization of toxic elements by the different immobilizing agents were determined by measuring the pH and conductivity of the leachates from the treated fly ash. A significant reduction in the concentration of the elements was observed for all the leachate samples obtained from the ashes treated with OS. The concentrations were reduced by 89%, 77%, 42% and 11% for Cr, Mo, As and Se, respectively. When SF was used for the ash treatment, the concentration reduction in the leachates was found to be above 60% for all elements. These results show that both the OS and SF can be used as immobilizing agents for the retention of toxic elements presented in coal ashes.

    Palavras-Chave: coal; fly ash; metals; toxic materials; leaching; surfactants; silanes

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  • IPEN-DOC 25878

    KOMATSU, L.G.H. ; ZAFALON, A.T. ; SANTOS, V.J. ; LINCOPAN, N.; RANGARI, V.K.; PARRA, D.F. . Application of natural nanoparticles in polymeric blend of HMSPP/SEBS for biocide activity. In: IKHMAYIES, SHADIA (Ed.); LI, JIAN (Ed.); VIEIRA, CARLOS M.F. (Ed.); MARGEM, JEAN I. (Ed.); BRAGA, FABIO de O. (Ed.). Green Materials Engineering. Cham, CZ, Switzerland: Springer Nature Switzerland AG, 2019. p. 79-87, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-030-10383-5_9

    Abstract: The natural nanoparticles of CaCO3, from eggshell and CaCO3/Ag, were investigated as candidates for biocide nanoparticles in a blend of thermoplastic elastomer, styrene–ethylene/butadiene–styrene (SEBS), and polyolefin, high-meltstrength polypropylene (HMSPP). The nanoparticles with silver (Ag) were synthesized by metal precursor method, and before the application in the polymer matrix, the nanoparticles were analyzed on dynamic lighting scattering (DLS) and Raman spectroscopy. After DLS and Raman analyses, the nanoparticles were evaluated in biocide tests against P. aeruginosa and S. auerus. The aim of this investigation was the blending and the injection molding in dumbbell samples with the nanoparticles. The characterizations were carried out by differential scanning calorimetry (DSC), thermogravimetry analysis,mechanical tests, X-ray diffraction, Raman spectroscopy, scanning electronmicroscopy, and energy-dispersive scanning and biocide tests. Correlation between size and particle distribution on the polymerwas founded. However, samples at higher concentrations (>1 wt%) do not show biocide activity.

    Palavras-Chave: nanoparticles; calcium carbonates; antimicrobial agents; polypropylene; mixing; styrene; butenes; ethylene

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  • IPEN-DOC 25877

    MUNITA, CASIMIRO S. ; GLASCOCK, MICHAEL D.; HAZENFRATZ, ROBERTO . Neutron activation analysis: an overview. In: ATTA-UR-RAHMAN (Ed.); OZKAN, SIBEL A. (Ed.). Recent Advances in Analytical Techniques. Sharjah, UAE: Bentham Science Publishers, 2019. p. 1-46, v. 3, cap. 5. DOI: 10.2174/9781681085722119030007

    Abstract: An overview of neutron activation analysis (NAA) and some applications for this technique are provided in this paper. The fundamentals of the various methods of NAA (INAA, relative, k0, large sample, prompt gamma charge particles, cyclic, molecular and radiochemical NAA) are discussed in order to describe the most important scientific and technical aspects. Several problems associated with the technique are pointed out and briefly discussed. Emphasis is laid on the advantages of this technique for the determination of trace elements in geological, biological and environmental samples as an alternative analytical technique where other methods would not be the best choice.

    Palavras-Chave: neutron activation analysis; elements; trace amounts; geologic deposits; neutron spectra

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  • IPEN-DOC 25876

    MOURA, ESPERIDIANA A.B. . The potential of micro- and nano-sized fillers extracted from agroindustry residues as reinforcements of thermoplastic-based biocomposites: a review. In: IKHMAYIES, SHADIA (Ed.); LI, JIAN (Ed.); VIEIRA, CARLOS M.F. (Ed.); MARGEM, JEAN I. (Ed.); BRAGA, FABIO de O. (Ed.). Green Materials Engineering. Cham, CZ, Switzerland: Springer Nature Switzerland AG, 2019. p. 89-100, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-030-10383-5_10

    Abstract: Currently, the relevance of reuse of agroindustrial waste to obtain fillers in micro- and nano-sizes for the development of biocomposite materials has grown significantly. Production processes based on sustainable and low carbon development have increased interest in more environmentally friendly polymer composites, which have made the origin of reinforcement materials a determining factor for their application in this segment. This work presents a review of the developments of our team in the field of thermoplastic biocomposites reinforced with micro- and nano-sized fillers extracted from agroindustry residues. The different residues from Brazilian agroindustry available for the extraction of micro- and nano-sized fillers for the production of polymer biocomposites, the methods of the extraction and treatments of these natural fillers are presented; and its application as reinforcements in thermoplastic-based biocomposite are discussed in this review.

    Palavras-Chave: agriculture; agricultural wastes; environmental impacts; bagasse; biodegradation; thermoplastics; composite materials; fillers; polymers

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  • IPEN-DOC 25875

    ORTIZ, NILCE . EPs antibiotics: photodecomposition and biocarbon adsorption. In: SOLONESKI, SONIA (Ed.). Emerging Pollutants. London, UK: IntechOpen, 2018. p. 79-97, cap. 5. DOI: 10.5772/intechopen.76893

    Abstract: The emerging pollutants (EPs) are considered a global monitoring challenge, present in the environment in very reduced concentrations, and the proper methods for sampling and analysis are still in development. Many published types of research considering the EPs identification only depend on the analytical methodology and a more efficient higher number of EPs. The quantitative determination of the prioritized EPs in water needs advanced and ultra-sensitive instrumental techniques applied in water, water-suspended matter, soil, and biota. The regulatory framework of the water-quality parameters does not often include the microplastics, EPs, and their metabolites; especially, the groundwater water-quality monitoring and control are urgent but not yet achieved. The EPs sources in water are the sewage, industrial, and agricultural waste discard, and the UN estimated that the wastewater produced annually is about 1500 km3, about six times more water than existing in all rivers of the word. In 2015, in China, which has a fast-growing economy, the water is a scarce resource with just 8% of the world’s fresh water to meet the water needs of the 22% of the world’s population.

    Palavras-Chave: pollution; antibiotics; carbon; chars; decomposition; photochemistry; water pollution

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  • IPEN-DOC 25874

    SANTOS, SOFIA N. dos; BERNARDES, EMERSON S. ; SANTOS-OLIVEIRA, RALPH. Nanoradiopharmaceuticals in current molecular medicine. In: BARHOUM, AHMED (Ed.); MAKHLOUF, ABDEL S.H. (Ed.). Fundamentals of Nanoparticles. Amsterdam, Netherlands: Elsevier, 2018. p. 553-569, cap. 18. DOI: 10.1016/B978-0-323-51255-8.00018-5

    Palavras-Chave: radiopharmaceuticals; nanotechnology; molecules; nuclear medicine; nanoparticles; radioisotopes

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  • IPEN-DOC 25873

    ESCANHOELA, CORDELIA M.F.; SABUNDJIAN, GAIANE ; LIMA, ANA C. de S. . Educação ambiental e sustentabilidade: um reator nuclear inovador para o Brasil. Revista Mais Educação, v. 2, n. 2, p. 220-229, 2019.

    Abstract: Este trabalho apresenta um estudo sobre a implementação do reator inovador System - Integrated Modular Advanced Reactor (SMART) no Brasil. Desenvolvido pelo Korea Atomic Energy Research Institute (KAERI) e com potência elétrica de 100MWe, esse reator pode atender a uma demanda de cerca de 100.000 habitantes. A escolha deste reator nuclear inovador está alicerçada, primeiramente, na análise do cenário energético nacional, no qual é demonstrada tanto a necessidade da expansão energética no Brasil quanto na imprescindível escolha de fontes alternativas de energia de maneira a atender as exigências de sustentabilidade e atenuação dos impactos ambientais. Dentro do contexto de complementariedade da matriz energética nacional associada à descentralização da geração de energia elétrica; o projeto envolvendo um reator nuclear pequeno e modular do tipo Power Water Reactor (PWR) prova ser uma escolha assertiva inclusive do ponto de vista econômico, já comprovado por meio de métodos econômicofinanceiros e ainda, pelo aproveitamento da expertise existente no país.

    Palavras-Chave: environment; sustainability; education; reactors; kaeri; power reactors; pwr type reactors; brazil; implementation; feasibility studies; economic impact; construction

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  • IPEN-DOC 25872

    MELLO-CASTANHO, SONIA R.H. ; MORENO, RODRIGO. Editorial: special issue on green and energy efficient processing. Journal of the European Ceramic Society, v. 39, n. 12, p. 3391-3391, 2019. DOI: 10.1016/j.jeurceramsoc.2019.05.066

    Palavras-Chave: energy efficiency; ceramics; renewable energy sources; environment; sustainability; meetings

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  • IPEN-DOC 25871

    PINTO, JOSE C.; CANEVAROLO, SEBASTIAO ; CARVALHO, ANTONIO J.F. de. Preface. Macromolecular Symposia, v. 383, n. 1, p. 1-1, 2019. DOI: 10.1002/masy.201970004

    Palavras-Chave: polymers; molecular structure; appropriate technology; meetings

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  • IPEN-DOC 25870

    SELLERA, FABIO P.; DUTRA, GUSTAVO H.P.; NASCIMENTO, CRISTIANE L.; RODRIGUES, FERNANDA P.; SÁ, LILIAN R.M. de; ALMEIDA-LOPES, LUCIANA; RIBEIRO, MARTHA S. ; POGLIANI, FABIO C.. Investigation of green turtle (Chelonia mydas) cutaneous fibropapillomatosis recurrence rates following diode laser surgery. Journal of Exotic Pet Medicine, v. 28, n. C, p. 180-184, 2019. DOI: 10.1053/j.jepm.2018.10.010

    Abstract: A pilot study was performed to investigate fibropapillomatosis (FP) recurrence rates after 940 nm-diode laser surgeries. Fifteen animals had a total of 274 tumors removed by diode laser. Cutaneous FP recurrence rates were evaluated during a period of 1-year. According to tumor sizes classification, 166 tumors (60.6%) were <1 cm, 67 tumors (24.5%) between 1-4 cm, 31 tumors (11.3%) >4-10 cm and 10 tumors (3.6%) >10 cm. Seven animals (46.6%) were lightly afflicted, 4 (26.7%) moderately, and 4 (26.7%) heavily afflicted. Thirteen animals (86.7%) did not present tumor regrowth and 2 (13.3%) presented small tumors after 1-year.

    Palavras-Chave: surgery; infectious diseases; turtles; veterinary medicine; neoplasms; lasers

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  • IPEN-DOC 25869

    SOUZA, ARMANDO C. de; ROSSI, JESUALDO L. ; CIONE, FRANCISCO C. ; MACHADO, NOE G.P. ; SILVA, ALINE C. da; SILVA, WALLACE F. da. Study of a metal-organic composite (Wx%Lig) for the gamma radiation attenuation. Research & Reviews: Journal of Material Sciences, v. 6, n. 4, p. 238-243, 2018. DOI: 10.4172/2321-6212.1000239

    Abstract: The objective of this work was to use tungsten and lignin as precursors to produce a metal-organic composite (Wx%Lig) using different sintering processes. Tungsten is a refractory metal and was selected for the composite due to its superior physical and mechanical properties (mechanical strength, high melting point, and excellent cross section with thermal neutrons). Its choice is also justified because it is widely used for high-energy radiation shielding. Lignin extracted from lignocellulosic biomass was selected to be the organic precursor for the composite because it has multiple applications; it is used in the production of aromatics, adhesives, and as a phenolic resin replacement. Analysis of the composite was performed after sintering processes using a Nexview 3D optical surface profiler and analyse the gamma radiation attenuation coefficient using cobalt source (Co-60). Metal-organic composites in ratios of W5%Lig and W2.5%Lig were produced after different heat treatment processes. Then, the gamma attenuation coefficients of the composite samples in these rations were analysing. The gradient of the attenuation coefficient differed when standard tungsten and the composites of W5%Lig and W2.5%Lig were compared with free source Co-60.

    Palavras-Chave: tungsten; lignin; composite materials; gamma radiation; sintering; refractory metals; attenuation; organic compounds; cobalt 60; computer codes

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  • IPEN-DOC 25868

    TEITELBAUM, SUSANA; ANDRADE, DELVONEI A. de ; PAREDES, WILBER E.B. . Perfil de pacientes oncológicos tratados con láser de baja intensidad. Dental Tribune Hispanic & Latin America, v. 15, n. 3, p. 14-19, 2018.

    Palavras-Chave: neoplasms; patients; human populations; therapy; radiotherapy; chemotherapy; statistical data; oral cavity; mucous membranes; inflammation; wounds

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  • IPEN-DOC 25867

    SILVA, J.O.; CALDAS, L.V.E. . Performance tests of a special ionization chamber for X-rays in mammography energy range. Brazilian Journal of Radiation Sciences, v. 6, n. 2A, p. 1-14, 2018. DOI: 10.15392/bjrs.v6i2%20-%20A.501

    Abstract: A special mammography homemade ionization chamber was developed to be applied for mammography energy range dosimetry. This chamber has a total sensitive volume of 6 cm³ and is made of a PMMA body and graphite coated collecting electrode. Performance tests as saturation, ion collection efficiency, linearity of chamber response versus air kerma rate and energy dependence were determined. The results obtained with this special homemade ionization chamber are within the limits stated in international recommendations. This chamber can be used in quality control programs of mammography energy range. All measurements were carried out at the Calibration Laboratory of IPEN.

    Palavras-Chave: dosimetry; ionization chambers; mammary glands; performance testing; pmma; quality control; x-ray radiography

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  • IPEN-DOC 25866

    BUSTILLOS, OSCAR V. . A ionização química como fonte de íons na espectrometria de massas. Revista Analytica, v. 17, n. 98, p. 34-35, 2019.

    Palavras-Chave: chemicals; ionization; mass spectroscopy; methionine; chemical reactions; proton reactions; electrons; ion sources

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  • IPEN-DOC 25865

    BUSTILLOS, OSCAR V. . A técnica de ionização por Electrospray na espectrometria de massas. Revista Analytica, v. 17, n. 99, p. 32-33, 2019.

    Palavras-Chave: mass spectroscopy; ionization; chromatography; electrostatics; sprays

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  • IPEN-DOC 25864

    GONÇALVES, LIVIA de S.; FRANCHI, MARIANA; MATHOR, MONICA B. ; LUGAO, ADEMAR B. ; CARVALHO, VICTOR H.; MEDEIROS, MARISA H.G.; ARTIOLI, GUILHERME G.; VARCA, GUSTAVO H.C. . The molecular structure of β-alanine is resistant to sterilising doses of gamma radiation. PLoS One, v. 14, n. 1, p. 1-13, 2019. DOI: 10.1371/journal.pone.0210713

    Abstract: β-alanine is the rate-limiting point for the endogenous synthesis of carnosine in skeletal muscle. Carnosine has a wide range of implications for health, normal function and exercise performance. Whilst the physiological relevance of carnosine to different tissues remains enigmatic, β-alanine administration is a useful strategy to investigate the physiological roles of carnosine in humans. Intravenous administration of β-alanine is an interesting approach to study carnosine metabolism. However, sterilisation is mandatory due to the nature of the administration route. We evaluated whether sterilising doses of gamma radiation damages the molecular structure and leads to the loss of functional characteristics of β-alanine. Pure β-alanine was sterilised by gamma radiation in sealed glass vials using a 60Co multipurpose irradiator at a dose rate of 8.5 kGy.hour-1 totalising 10, 20, 25 30 and 40 kGy. The molecular integrity was assessed by X-ray Diffraction and changes in content were determined by High Performance Liquid Chromatography (UV-HPLC) and Triple Quadrupole Mass Spectrometer (HPLC/MS-MS). Sterility assurance was evaluated by inoculation assay. To examine whether functional properties were preserved, β-alanine was infused in one participant, who rated the level of paraesthesia on the skin using a 0–3 scale. Urinary β-alanine was quantified before and 24-h following β-alanine infusion using HPLC-ESI+-MS/MS. Irradiation resulted in no change in the crystal structure of β-alanine, no degradation, and no new peaks were identified in the dose range assayed. The inoculation assay showed the absence of viable microorganisms in all β-alanine samples, including those that did not undergo irradiation. Intravenous infusion of β-alanine resulted in paraesthesia and it detected in the urine as per normal. We conclude that gamma radiation is a suitable technique for the sterilisation of β-alanine. It does not lead to degradation, damage to the β-alanine structure, content or loss of function within the evaluated irradiation conditions.

    Palavras-Chave: alanine-beta; gamma radiation; sterilization; irradiation; intravenous injection; radiation doses

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  • IPEN-DOC 25863

    CHURA-CHAMBI, ROSA M. ; SILVA, CLEIDE M.R. da ; PEREIRA, LENNON R.; BARTOLINI, PAOLO ; FERREIRA, LUIS C. de S.; MORGANTI, LIGIA . Protein refolding based on high hydrostatic pressure and alkaline pH: application on a recombinant dengue virus NS1 protein. PLoS One, v. 14, n. 1, p. 1-14, 2019. DOI: 10.1371/journal.pone.0211162

    Abstract: In this study we evaluated the association of high hydrostatic pressure (HHP) and alkaline pH as a minimally denaturing condition for the solubilization of inclusion bodies (IBs) generated by recombinant proteins expressed by Escherichia coli strains. The method was successfully applied to a recombinant form of the dengue virus (DENV) non-structural protein 1 (NS1). The minimal pH for IBs solubilization at 1 bar was 12 while a pH of 10 was sufficient for solubilization at HHP: 2.4 kbar for 90 min and 0.4 kbar for 14 h 30 min. An optimal refolding condition was achieved by compression of IBs at HHP and pH 10.5 in the presence of arginine, oxidized and reduced glutathiones, providing much higher yields (up to 8-fold) than association of HHP and GdnHCl via an established protocol. The refolded NS1, 109 ± 9.5 mg/L bacterial culture was recovered mainly as monomer and dimer, corresponding up to 90% of the total protein and remaining immunologically active. The proposed conditions represent an alternative for the refolding of immunologically active recombinant proteins expressed as IBs.

    Palavras-Chave: viruses; viral diseases; proteins; ph value; hydrostatics; pressure dependence; immunoassay

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  • IPEN-DOC 25706

    VERRIJSSEN, AN-SOFIE; OPBROEK, THIRZA; BELLEZZO, MURILLO ; FONSECA, GABRIEL P.; VERHAEGEN, FRANK; GERARD, JEAN-PIERRE; MYINT, ARTHUR S.; LIMBERGEN, EVERT J.V.; BERBEE, MAAIKE. A systematic review comparing radiation toxicity after various endorectal techniques. Brachytherapy, v. 18, n. 1, p. 71-86, 2019. DOI: 10.1016/j.brachy.2018.10.001

    Observação: Corrigendum anexado. Brachytherapy, v. 18, p. 427, 2019. DOI: 10.1016/j.brachy.2019.03.010

    Abstract: PURPOSE: A clinical complete response is seen after neoadjuvant chemoradiation for rectal tumors in 15%e20% of patients. These patients can potentially be spared mutilating total mesorectal excision surgery through a watch-and-wait policy. Recent studies show that dose escalation by a radiation boost increases the clinical complete response rate. The boost dose to the tumor can be administered through external beam radiotherapy or through internal radiotherapy using techniques like contact therapy, low-dose-rate or high-dose-rate brachytherapy (BT). However, limited information is available concerning treatment-related toxicity of these techniques. With this systematic review, we aim to summarize and compare published data concerning acute and late toxicity after contact X-ray therapy (CXT) and BT for rectal cancer. METHODS AND MATERIALS/RESULTS: Thirty-eight studies reporting toxicity after endorectal radiation techniques for rectal cancer were included, resulting in 3682 patients for analysis. Direct comparison of toxicity by the different radiation modes was hampered by various combinations of endorectal techniques, a lack of clear reporting of toxicity scores, dose prescription, technique used, and treated volumes. $ Grade 3 rectal toxicity was reported in 2.9% of patients having received only CXT; 6.3% of patients who received only BT had Grade 3 rectal toxicity, and BT also caused Grade 3 urinary toxicity in 1 patient. CONCLUSION: All techniques reported some$Grade 3 toxicity. Toxicity after CXTwas confined to the rectum, whereas after BT, urogenital toxicity and skin toxicity were seen as well. Unfortunately, few specific conclusions could be drawn regarding the dose-related risk of toxicity for the various techniques due to nonuniform reporting strategies and missing information. To enable future comparisons and improvements, the endorectal radiation field urgently needs consensus guidelines on dose reporting, dose prescription, treatment volume specification, and toxicity reporting. 2018 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

    Palavras-Chave: chemotherapy; brachytherapy; neoplasms; rectum; radiation doses; toxicity; intestines

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  • IPEN-DOC 25860

    PARREIRA, LUANNA S.; ANTONIASSI, RODOLFO M. ; FREITAS, ISABEL C.; OLIVEIRA, DANIELA C. de; SPINACE, ESTEVAM V. ; CAMARGO, PEDRO H.C.; SANTOS, MAURO C. dos. MWCNT-COOH supported PtSnNi electrocatalysts for direct ethanol fuel cells: low Pt content, selectivity and chemical stability. Renewable Energy, v. 143, p. 1397-1405, 2019. DOI: 10.1016/j.renene.2019.05.067

    Abstract: PtSnNi electrocatalysts (60: 40: 40 mass ratio) supported on Vulcan® XC-72 (Cabot) carbon and COOHfunctionalized multiwalled carbon nanotubes (Cheaptubes®) with 15% of metal loading were prepared. The nanoparticles size of 2e3 nm for both supports was estimated by HRTEM. In the direct ethanol fuel cell experiments, PtSnNi/C presents 50 mA cm 2 reaching the maximum power density (MPD) of 12mWcm 2 and decreasing at higher currents, while PtSnNi/MWCNT-COOH obtains similar values of MPD (60 mA cm 2), but keeping the best performance. By GC (gas chromatography) technique, it was possible to observe that the electrocatalyst supported on MWCNT-COOH favored the ethanol oxidation to acetaldehyde and acetic acid, although the material supported on Vulcan® XC-72 carbon presented almost 100% of selectivity for acetaldehyde. This behavior was maintained also when the current of 0.1 A was applied for 80 min. For the PtSnNi/C electrocatalyst, the selectivity to only acetaldehyde can be related to Sn and Ni dissolution process that can become the electrocatalytic activity similar to Pt/C, decreasing the power density as observed in our experiments. Established by EDS analysis, after 80 min of polarization, the Ni and Sn relative atomic ratio was lower on the catalytic anodic layer of PtSnNi/C than on PtSnNi/MWCNT-COOH.

    Palavras-Chave: gas chromatography; electrocatalysts; carbon nanotubes; carboxylase; platinum; tin oxides; ethanol; direct ethanol fuel cells

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  • IPEN-DOC 25859

    POZZO, LORENA ; MONTEIRO, LUCILENA R. ; CERCI, JULIANA J.; FANTI, STEFANO; NEGRO, ANTONELLA; TRINDADE, EVELINDA. HTA in nuclear medicine: [Ga-68]PSMA PET/CT for patients with prostate cancer. Clinical and Translational Imaging, v. 7, n. 1, p. 7-20, 2019. DOI: 10.1007/s40336-019-00313-8

    Abstract: The [ 68Ga]PSMA PET/CT has been an option on clinical research tools to stage and to restage prostate cancer patients, although, with promising results, this radiopharmaceutical cannot be commercialized yet. Hence, up to date, [ 68Ga]PSMA has been used in a clinical research context. Once regulatory body approved it for marketing, health systems are responsible for the reimbursement decision. Health Technology Assessments (HTA) tools should be considered to base and to help decision-makers to spread or not this new technology. Regarding [ 68Ga]PSMA, under HTA framework, the present study searched for secondary studies and hence assessed three systematic reviews with meta-analyses published considering prostate cancer patients in different scenarios, same imaging technology but different comparators and outputs. The secondary studies considered outputs such as accuracy, detectability, positivity and change of management. Using AMSTAR-2, the meta-analysis methods and results were evaluated with 16 questions able to identify critical weaknesses, such as risk of bias, publication bias, true effect, and study heterogeneity. To increase the observational number of patients, to register positive and negative findings, and consolidate regional and multi-center clinical data which were suggestions on study design, structure and statistics made to improve the quality in future primary and secondary studies.

    Palavras-Chave: nuclear medicine; prostate; neoplasms; antigens; carcinomas; public health; technology assessment

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  • IPEN-DOC 25858

    PETRI, A.R. ; MANGIAROTTI, A.; GONCALVES, J.A.C. ; BUENO, C.C. . Effect of the ohmic drop in a RPC-like chamber for measurements of electron transport parameters. Brazilian Journal of Radiation Sciences, v. 7, n. 2A, p. 1-11, 2019. DOI: 10.15392/bjrs.v7i2A.637

    Abstract: The main advantage of Resistive Plate Chambers (RPCs), applied, for instance, in High-Energy Experiments and Positron Emission Tomography (PET), is that it is spark-protected due to the presence of, at least, one high-resistive electrode. However, the ohmic drop across the latter can affect the charge multiplication significantly. In this work, we investigate this effect in a RPC-like chamber. The counter was filled with nitrogen at atmospheric pressure and the primary ionization was produced by the incidence of nitrogen pulsed laser beam on an aluminum cathode. The illumination area of the cathode was measured using a foil of millimetric paper overlaid on this electrode. In this way, the resistance of the glass anode could be estimated using the known resistivity of the glass (ρ=2×1012 Ω.cm). Therefore, the voltage drop across the dielectric was calculated by the product of the current across the gas gap and the anode resistance. In order to mitigate the effect of the resistive electrode, the laser beam intensity was limited by interposing metallic meshes between the laser and the chamber window. The dependence of the ohmic drop from the applied voltage was analyzed. The results obtained shown that, without the meshes, the ohmic drop corresponds up to 7% of the applied voltage, preventing the detection system to reach values of density-normalized electric fields in the gas gap (Eeff/N) higher than 166 Td. By minimizing the laser beam intensity and, consequently, the primary ionization, the ohmic drop represented only 0.2% of the applied voltage, extending the Eeff /N range up to 175 Td.

    Palavras-Chave: voltage drop; charged-particle transport; electrons; dielectric materials; electric potential; electric conductivity; mesh generation; electrodes; laser radiation

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  • IPEN-DOC 25857

    OLIVEIRA-SILVA, TAMIRES de; ALVARENGA, LETICIA H.; LIMA-LEAL, CINTIA; GODOY-MIRANDA, BIANCA; CARRIBEIRO, PAMELA; SUZUKI, LUIS C. ; RIBEIRO, MARTHA S. ; KATO, ILKA T.; PAVANI, CHRISTIANE; PRATES, RENATO A.. Effect of photodynamic antimicrobial chemotherapy on Candida albicans in the presence of glucose. Photodiagnosis and Photodynamic Therapy, v. 27, p. 54-58, 2019. DOI: 10.1016/j.pdpdt.2019.05.032

    Abstract: Background: Candida albicans is an opportunistic commensal microorganism, often associated with severe infections in immunosuppressed individuals. C. albicans has hexose transporters that may favor the intracellular accumulation of photosensitizer (PS). the aims of this study were to investigate the influence of glucose load on photodynamic antimicrobial chemotherapy (PACT); and the role that membrane transport system plays on this therapy in the presence of glucose. Material and methods: Strains of C. albicans were selected: ATCC 10231, YEM 12, YEM 13, YEM 14 and YEM 15. All strains were grown aerobically on Sabouraud agar and incubated at 30 °C for 24 h. The strains were treated with and without glucose, and divided into Control (no treatment), LED light (660 nm, 166 mW/cm2), Photosensitizer (100 μM methylene blue) and PACT at 1, 3 and 6 min of irradiation groups. The colony forming units were counted and data submitted to statistical analysis (ANOVA) and Tukey's test. The concentration of methylene blue (MB) outside the yeast was measured by fluorescence spectroscopy. Results: PACT inactivate C. albicans and the presence of glucose did not affect the killing effect for most strains. Only YEM12 was partially affected by its presence. Regarding efflux systems, ABC overexpressing strain showed a protective effect on the yeast cells. We observed that yeast with overexpression of major facilitator superfamily (MFS) membrane pore tended to accumulate more MB in its cytoplasm, whereas strains that overexpressed ABC pumps (ATP-binding cassette transporters) tended to decrease MB uptake and survive the photodynamic challenge. Conclusion: Presence of glucose showed a small effect on PACT . The accumulation of MB on yeast induces more photodynamic inactivation; however, the photodynamic efficacy depends on the type and characteristics of the microbial strain.

    Palavras-Chave: chemotherapy; antimicrobial agents; photosensitivity; yeasts; candida; glucose; methylene blue; x-ray fluorescence analysis

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  • IPEN-DOC 25856

    JUNOT, DANILO O. ; SANTOS, ANA G.M.; ANTONIO, PATRICIA L. ; REZENDE, MARCOS V.S.; SOUZA, DIVANIZIA N.; CALDAS, LINDA V.E. . Dosimetric and optical properties of CaSO4:Tm and CaSO4:Tm,Ag crystals produced by a slow evaporation route. Journal of Luminescence, v. 210, p. 58-65, 2019. DOI: 10.1016/j.jlumin.2019.02.005

    Abstract: The motivation of this work was to produce TL dosimeters based on crystals of CaSO4 doped with thulium and silver, by means of a suitable new route. The crystals were produced by an adaptation of the slow evaporation route using calcium carbonate (CaCO3) as precursor, and incorporating the dopants (Tm2O3 and silver nanoparticles) in a solution of sulfuric acid, which is evaporated resulting in CaSO4:Tm or CaSO4:Tm,Ag crystal powders. X-ray diffraction analyses showed that the produced samples exhibit only a single phase corresponding to the crystal structure of anhydrite. Optical characterization was performed to determine the band gap of the materials. Samples did not show a reasonable OSL signal after stimulation with blue LEDs. TL characteristics such as glow curves, linearity and reproducibility of response, minimum detectable dose and fading were evaluated. The CaSO4:Tm samples showed TL emission glow curves with peaks in temperatures proper for dosimetry. The CaSO4:Tm,Ag samples presented a very intense peak displaced to high temperatures that could only be observed by applying heating rates below 4 °C/s. Samples doped with thulium oxide and silver nanoparticles showed the highest TL intensity and lowest fading.

    Palavras-Chave: dosimetry; thermoluminescence; crystals; calcium sulfates; thermoluminescent dosimetry; thulium oxides; silver; calcium carbonates

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  • IPEN-DOC 25855

    AGUIAR, D.J.M. de; PADILHA, A.F.; PLAUT, R.L.; SILVA, M.R. da; LIMA, N.B. de . Comparative study on the forming and reversion of strain-induced martensite in two duplex stainless steels: developing a model for VSM. Journal of Magnetism and Magnetic Materials, v. 485, p. 8-15, 2019. DOI: 10.1016/j.jmmm.2019.04.054

    Abstract: An original feature of this work is the proposal of two equations to fit the volume fraction of ferromagnetic (α+α′) phases that can be applied in the measurement of magnetic saturation of comminuted duplex and superduplex stainless steels (for example, powders or filed chips). Duplex stainless steels contain similar volume fractions of austenite (γ) and ferrite (α) in their microstructure. Two steels exemplify this class, namely the most widely used duplex UNS S31803 and superduplex UNS S32520 stainless steels. The phenomena of work hardening, formation, and reversion of strain-induced martensite (α′) in austenite were compared in both stainless steels. Samples were work-hardened and annealed under identical conditions, and their behavior was evaluated mainly through X-ray diffraction and magnetic measurements. Notably, the volume fraction of strain-induced α′ in duplex stainless steel was as high as 32%, which indicated that this steel had a greater tendency to form α′ than superduplex stainless steel, for which the corresponding value equaled 15%. Annealing at 650 °C for 2 h promoted the reversion of strain-induced α′ into γ, decreasing the volume fraction of the former phase from 32 to 2% (duplex) and from 15 to 6% (superduplex).

    Palavras-Chave: x-ray diffraction; stainless steels; martensite; chemical composition; ferromagnetism; magnetic fields; equations

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  • IPEN-DOC 25854

    GABBAI-ARMELIN, P.R.; FERNANDES, K.R.; MAGRI, A.M.P.; SILVA, A.C. da ; FORTULAN, C.A.; RENNO, A.C.M.. Characterization and cytotoxicity evaluation of bio-inspired bioactive Glass/Collagen/Magnesium composites. Materials Chemistry and Physics, v. 228, p. 201-209, 2019. DOI: 10.1016/j.matchemphys.2019.02.072

    Abstract: Bone fractures are a common clinical event related to trauma, aging or diseases. Since bone repair is complex, abnormal consolidation may occur or, even, non-union. Biomaterials have a key role in this context, since they can stimulate bone cell differentiation, accelerating the healing process. Bioactive glasses (BG) represent a promising class of biomaterials due to its high bioactivity and osteogenic potential. Nevertheless, the osteoconductive properties of BG may not be enough to stimulate consolidation in critical situations. Thus, it was hypothesized that enriching BG with other materials such as collagen (Col) and magnesium (Mg), trying to make a composite with similar properties to bone tissue, would constitute a more suitable graft for tissue engineering. This work aimed at obtaining BG/Col/Mg composites and evaluating their physicochemical features. Moreover, L929 and MC3T3-E1 cell culture studies were done to investigate the cytotoxicity of the composites. The results showed that Mg could be successfully introduced, at different percentages (1, 3 and 5%), into BG and BG/Col composites, improving mechanical properties and retaining the bioactivity of BG. Ca assay measurements demonstrated that reactions in the Mg/solution interface, i.e. reactions between Mg and the ions in the simulated body fluid (SBF) have led to an increased Ca uptake for compositescontaining 3 and 5% Mg compared to plain BG and BG/Col. In vitro studies showed that BG and BG/Col containing 1% of Mg were non-cytotoxic and biocompatible. This percentage of Mg is promising for forward works. Our data on the present BG/Mg and BG/Col/Mg-based composites are encouraging and may lead to further molecular and cell culture studies, and in vivo investigations to clarify the biological performance of these new biomaterials.

    Palavras-Chave: skeleton; toxicity; collagen; magnesium; glass; composite materials; skeletal diseases; biological repair; biological materials

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  • IPEN-DOC 25853

    PINHEIRO, ANDRE L.G.; CARMO, JOSE V.C. do; CARVALHO, DAVI C.; OLIVEIRA, ALCINEIA C.; RODRIGUEZ-CASTELLON, ENRIQUE; TEHUACANERO-CUAPA, SAMUEL; OTUBO, LARISSA ; LANG, ROSSANO. Bio-additive fuels from glycerol acetalization over metals-containing vanadium oxide nanotubes (MeVOx-NT in which, Me=Ni, Co, or Pt). Fuel Processing Technology, v. 184, p. 45-56, 2019. DOI: 10.1016/j.fuproc.2018.11.008

    Abstract: The biodiesel production has led to a drastic surplus of glycerol and catalytic conversion of glycerol into valueadded products is of great industrial importance. Thus, the acetalization of glycerol with ketone or aldehydes allows the glycerol transformation into bio–additive fuels. In this work, metals-containing vanadium oxides nanotubes (MeVOx NT in which, Me=Co, Pt or Ni) have been synthesized with additional internal porosity and tested in the acetalization of glycerol with acetone (AG) for valuable biofuels production. The catalysts showed remarkable performances in the AG reaction. Furthermore, by variation of the composition, catalyst loading and temperature and using distinct substrates (butyraldehyde, furfuraldehyde and benzaldehyde), NiVOxNT is active, being very selective to solketal and reciclable for 4 times in the AG reaction. On the contrary, pure VOx NT easily deactivated due to the structure agent removal during the reaction, which promote the collapse of the tubular structure. The CoVOxNT and PtVOxNT catalysts did not exhibit such a stable structure and easily deactivated in the reaction due to leaching of the metals oxides during the AG.

    Palavras-Chave: biodiesel fuels; glycerol; nanotubes; vanadium oxides; biofuels; acetates; catalysts; acetone

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  • IPEN-DOC 25851

    BENEDETTO, RAQUEL ; MASSICANO, ADRIANA V.F.; CRENSHAW, BRYANT K.; OLIVEIRA, RENATO; REIS, RUI M.; ARAUJO, ELAINE B. ; LAPI, SUZANNE E.. Zr-89-DFO-cetuximab as a molecular imaging agent to identify cetuximab resistance in head and neck squamous cell carcinoma. Cancer Biotherapy and Radiopharmaceuticals, v. 34, n. 5, p. 288-296, 2019. DOI: 10.1089/cbr.2018.2616

    Abstract: Background: Despite the improvement in clinical outcomes for head and neck squamous cell carcinoma (HNSCC) as the result of cetuximab, patients may present with or develop resistance that increases tumor recurrence rates and limits clinical efficacy. Therefore, identifying those patients who are or become resistant is essential to tailor the best therapeutic approach. Materials and Methods: Cetuximab was conjugated to p-NCS-Bz-DFO and labeled with 89Zr. The resistance model was developed by treating FaDu cells with cetuximab. Western blotting (WB) and specific binding assays were performed to evaluate epidermal growth factor receptor (EGFR) expression and 89Zr-DFO-cetuximab uptake in FaDu cetuximab-resistant (FCR) and FaDu cetuximab-sensitive (FCS) cells. Positron emission tomography imaging and biodistribution were conducted in NU/NU nude mice implanted with FCR or FCS cells. Results: Cetuximab was successfully radiolabeled with 89Zr (‡95%). Binding assays performed in FCR and FCS cells showed significantly lower 89Zr-DFO-cetuximab uptake in FCR ( p < 0.0001). WB suggests that the resistance mechanism is associated with EGFR downregulation ( p = 0.038). This result is in agreement with the low uptake of 89Zr-DFO-cetuximab in FCR cells. Tumor uptake of 89Zr-DFO-cetuximab in FCR was significantly lower than FCS tumors ( p = 0.0340). Conclusions: In this work, the authors showed that 89Zr-DFO-cetuximab is suitable for identification of EGFR downregulation in vitro and in vivo. This radiopharmaceutical may be useful for monitoring resistance in HNSCC patients during cetuximab therapy.

    Palavras-Chave: zirconium 89; positron computed tomography; carcinomas; radiopharmaceuticals; therapy; chemotherapy; antibodies; reagents

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  • IPEN-DOC 25850

    FRIMAIO, AUDREW ; NASCIMENTO, BRUNA C.; BARRIO, RAMON M.M.; CAMPOS, LETICIA L. ; COSTA, PAULO R.. X-ray spectrometry applied for determination of linear attenuation coefficient of tissue-equivalent materials. Radiation Physics and Chemistry, v. 160, p. 89-95, 2019. DOI: 10.1016/j.radphyschem.2019.03.021

    Observação: Reprint anexado. Radiation Physics and Chemistry, v. 167, 2020. DOI: 10.1016/j.radphyschem.2019.108553

    Abstract: Resin-based materials equivalent to water were developed and four different samples were obtained. The linear attenuation coefficients of all samples was evaluated using X-ray spectrometry with primary and transmitted beams using voltages at the ranging from 60 to 120 kV. The experimental measured values were compared with theoretical reference values to water and with that obtained using the Least Square Method algorithm methodology (method applied to diagnostic radiology and radiotherapy). Our results show that differences between the measured values and the target μ(E) was lower than 7% ± 0.3 in the energy range from 20 to 80 keV. These results enable to consider that the material developed and produced is a good option to be used as a waterequivalent material and the experimental method adequate to its quantitative evaluation.

    Palavras-Chave: phantoms; x-ray tubes; tissue-equivalent materials; attenuation; spectroscopy; samplers; resins

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  • IPEN-DOC 25849

    BARROSO, A.G. ; GARCIA, R.H.L. ; DEL MASTRO, N.L. . X-ray diffraction pattern and relative crystallinity of irradiated arrowroot starch. Brazilian Journal of Radiation Sciences, v. 7, n. 2A, p. 1-7, 2019. DOI: 10.15392/bjrs.v7i2A.645

    Abstract: After cereals, tubers and roots are the major source of starch for food and industrial uses. Arrowroot refers to any plant of the genus Marantha, but the term is most commonly used to describe the easily digested starch ob-tained from the rhizomes of Marantha arundinacae. The rhizomes of this herbaceous plant contain about 20% of starch. As few studies exist on arrowroot starch, the objective of this preliminary work was to study the X-ray diffraction (XRD) patterns of arrowroot starch when treated by γ-radiation with doses up to 15 kGy in a 60Co source. The XRD patterns of the arrowroot starch exhibited A-type crystalline arrangements with strong peaks at approximately 15º, 17º, 18º and 23º (2θ). A slight increase of diffractogram peaks intensity was noticed after the irradiation process. The cristallinity index was calculated using Bruker DIFFRAC.EVA version 4.2 software. Relative crystallinity seems to increase with irradiation at low doses that could be attributed to different radia-tion sensitivity among the amorphous and crystalline regions of the arrowroot starch molecule. Present results will contribute to elucidate the behavior under radiation treatment of this starchy component increasingly em-ployed by the food industry.

    Palavras-Chave: x-ray diffraction; gamma radiation; starch; radiation effects; radiation doses; cobalt 60; crystal structure; irradiation

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  • IPEN-DOC 25848

    ICHIKAWA, R.U. ; LINHARES, H.M.S.M.D.; SILVA, A.S.B. da ; TEIXEIRA, M.I. ; RANIERI, I.M. ; TURRILLAS, X.; MARTINEZ, L.G. . X-ray diffraction analysis of KY3F10 nanoparticles doped with Nd and preliminary studies for its use in high-dose radiation dosimetry. Brazilian Journal of Radiation Sciences, v. 7, n. 2A, p. 1-13, 2019. DOI: 10.15392/bjrs.v7i2A.586

    Abstract: In this work, the structure and microstructure of Nd:KY3F10 nanoparticles was probed using X-ray synchrotron diffraction analysis. Rietveld refinement was applied to obtain cell parameters, atomic positions and atomic dis-placement factors to be compared with the ones found in literature. X-ray line profile methods were applied to determine mean crystallite size and crystallite size distribution. Thermoluminescent (TL) emission curves were measured for different radiation doses, from 0.10 kGy up to 10.0 kGy. Dose-response curves were obtained by area integration beneath the peaks from TL. The reproducibility of the results in this work has shown that this material can be considered a good dosimetric material.

    Palavras-Chave: nanoparticles; x-ray diffraction; radiation doses; doped materials; thermoluminescence; neodymium; yttrium fluorides; critical size; dose-response relationships; dosimetry

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  • IPEN-DOC 25847

    ANDRADE, ADRIANO B.; BISPO, GIORDANO F. da C.; MACEDO, ZELIA S.; BALDOCHI, SONIA L. ; YUKIHARA, EDUARDO G.; VALERIO, MARIO E.G.. VUV excited luminescence and thermoluminescence investigation on Er3+- or Pr3+-doped BaY2F8 single crystals. Optical Materials, v. 90, p. 238-243, 2019. DOI: 10.1016/j.optmat.2019.02.044

    Abstract: Photoluminescence (PL), thermoluminescence (TL) emission spectra and TL glow curves of barium yttrium fluoride (BaY2F8 – BaYF), undoped and doped with erbium (Er3+) or praseodymium (Pr3+) were measured to investigate the fundamental absorption (band gap – Eg), the nature of the trapping centers, as well as the electronic transitions of Ln3+ in BaYF host. The band gap energy Eg of BaY2F8 was determined by vacuum ultraviolet (VUV) excitation measurements to be around 11.2 eV. Additionally, the electronic transition from excited states of Ln3+ ions and the exciton state were also identified. TL emission spectra showed that the TL emission of doped samples is related to the Ln3+ ion, indicating that the related host trapping centers are not affected by the new trapping centers originated due the dopant ions. Trap depths were calculated by fitting the glow curves using a first order kinetics model. Host-related trapping centers were attributed to intrinsic defects such as Vk and F centers and the new TL peaks observed for Ere and Pr-doped samples was associated to the electrons trapping centers. These results lead us to propose a simple model to explain the origin of the TL emission in BaYF.

    Palavras-Chave: ultraviolet spectra; spectroscopy; barium fluorides; yttrium fluorides; thermoluminescence; photoluminescence; emission spectra; monocrystals

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  • IPEN-DOC 25846

    SOUZA, C.H. ; SHORTO, J.M.B. ; SIQUEIRA, P.T.D. ; NUNES, M.G. ; SILVA JUNIOR, I.A. ; YORIYAZ, H. . Verification of angular dependence in MOSFET detector. Brazilian Journal of Radiation Sciences, v. 7, n. 2A, p. 1-11, 2019. DOI: 10.15392/bjrs.v7i2A.734

    Abstract: In vivo dosimetry is an essential tool for quality assurance programs, being a procedure commonly performed with thermoluminescent dosimeters (TLDs) or diodes. However, a type of dosimeter that has increasing popularity in recent years is the metal-oxide-semiconductor field effect transistor (MOSFET) detector. MOSFET dosimeters fulfill all the necessary characteristics to realize in vivo dosimetry since it has a small size, good precision and feasibility of meas-urement, as well as easy handling. Nevertheless, its true differential is to allow reading of dose in real time, enabling immediate intervention in the correction of physical parameters deviations and anticipation of small anatomical changes in the patient during treatment. In order for MOSFET dosimeter to be better accepted in clinical routine, information reporting performance should be available frequently. For this reason, this work proposes to verify reproducibility and angular dependence of a standard sensitivity MOSFET dosimeter (TN-502RD-H) for Cs-137 and Co-60 sources. Exper-imental data were satisfactory and MOSFET dosimeter presented a reproducibility of 3.3% and 2.7% (±1 SD) for Cs-137 and Co-60 sources, respectively. In addition, an angular dependence of up to 6.1% and 16.3% for both radioactive sources, respectively. It is conclusive that MOSFET dosimeter TN-502RD-H has satisfactory reproducibility and a considerable angular dependence, mainly for the Co-60 source. This means that although precise measurements, special attention must be taken for applications in certain anatomical regions in a patient.

    Palavras-Chave: mosfet; experimental data; dosemeters; dosimetry; in vivo; performance; cesium 137; cobalt 60; irradiation; neoplasms

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  • IPEN-DOC 25845

    CARVALHO, P.R. ; MUNITA, C.S. ; LAPOLLI, A.L. . Validity studies among hierarchical methods of cluster analysis using cophenetic correlation coefficient. Brazilian Journal of Radiation Sciences, v. 7, n. 2A, p. 1-14, 2019. DOI: 10.15392/bjrs.v7i2A.668

    Abstract: The literature presents many methods to produce data set clusters and the better method choice becomes hardest because the various combinations between them based on different dissimilarity measures can lead to different cluster patterns and false interpretations. Nevertheless, little effort has been expended in evaluating these methods empirically using an archeological data set. In this way, this work has the objective to develop a comparative study of the cluster analysis methods and to identify what is the most appropriate for an archeological data set. For this, 45 ceramic fragments samples data set was analyzed by instrumental neutron activation analysis (INAA). And, five hierarchical methods of cluster were used to this data set: Single linkage, Complete linkage, Average linkage, Centroid and Ward. The validation was done calculating cophenetic correlation coefficient values by a statistical program R and the comparison between them showed the average linkage method was more accurate for the 45 ceramic fragments samples data set. With this, the statistical program R showed be an tool option for other scientists to calculate their cophenetic correlation coefficient and to identify the more accurate methods for their archeological data set.

    Palavras-Chave: validation; neutron activation analysis; archaeology; quality control; comparative evaluations; ceramics; multivariate analysis; cluster analysis; elements

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  • IPEN-DOC 25844

    DEL NERO, R.A. ; NAKANDAKARI, M.V.N.; YORIYAZ, H. . Validating a virtual source model based in Monte Carlo method for profiles and percent depth doses calculation. Brazilian Journal of Radiation Sciences, v. 7, n. 2A, p. 1-8, 2019. DOI: 10.15392/bjrs.v7i2A.689

    Abstract: The Monte Carlo method for radiation transport has been adapted for medical physics application. More specifically, it has received more attention in clinical treatment planning with the development of more efficient computer simulation techniques. In linear accelerator modeling by the Monte Carlo method, the phase space data file (phsp) is an alternative representation for radiation source. However, to create a phase space file and obtain good precision in the results, it is necessary detailed information about the accelerator's head and commonly the supplier does not provide all the necessary data. An alternative to the phsp is the Virtual Source Model (VSM). This alternative approach presents many advantages for the clinical Monte Carlo application. This is the most efficient method for particle generation and can provide an accuracy similar when the phsp is used. This research propose a VSM simulation with the use of a Virtual Flattening Filter (VFF) for profiles and percent depth doses calculation. Two different sizes of open fields (40 x 40 cm² and 40 x 40 cm² rotated 45°) were used and two different source to surface distance (SSD) were applied: the standard 100 cm and custom SSD of 370 cm, which is applied in radiotherapy treatments of total body irradiation. The data generated by the simulation was analyzed and compared with experimental data to validate the VSM. This current model is easy to build and test.

    Palavras-Chave: calculation methods; monte carlo method; validation; radiation dose distributions; radiation transport; computerized simulation; v codes; whole-body irradiation; phase space

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  • IPEN-DOC 25843

    YAMAGATA, C. ; LEME, D.R. ; CASTANHO, S.R.H.M. . Use of waste water glass as silica supplier in synthesis of pure and Mg-doped lanthanum silicate powders for IT-SOFC application. Journal of the European Ceramic Society, v. 39, n. 12, p. 3416-3420, 2019. DOI: 10.1016/j.jeurceramsoc.2019.03.045

    Abstract: Water glass in alkali solution (Na2SiO3/NaOH) an abundant effluent, generated in the alkaline fusion of zircon sand, represents a potential silica source to be converted in useful silica technological application. Actually, the generation of energy by environmental-friendly method is one of the major challenges for researchers. Solid Oxide Fuel Cells (SOFC) is efficient and environmentally clean technique to energy production, since it converts chemical energy into electrical power, directly. Apatite-type lanthanum silicates are promising materials for application as an electrolyte in intermediate temperature SOFC (IT-SOFC) because of their higher ionic conductivity, in temperatures of range 600–700 °C, than conventional zirconia electrolytes. In this work, pure (La9,56(SiO4)6O2,34) and Mg-doped (La9,8Si5,7Mg0,3O26,4) lanthanum silicate were synthesized, from that rich effluent. Using the sol-gel followed by precipitation method, the single crystalline apatite phase of both silicates was obtained by thermal treatment at 900 °C of their precursors. Sintered ceramic samples reached density of higher than 90%.

    Palavras-Chave: waste water; electrolytes; lanthanum silicates; synthesis; sol-gel process; glass; solid oxide fuel cells; precipitation; apatites; silicates

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  • IPEN-DOC 25842

    CARVALHO, LUMA R. de ; BONFIM, LETICIA ; VIEIRA, DANIEL P. . Use of 2-color flow cytometry to assess radiation-induced genotoxic damage on CHO-KI cells. Brazilian Journal of Radiation Sciences, v. 7, n. 2A, p. 1-13, 2019. DOI: 10.15392/bjrs.v7i2A.570

    Abstract: The micronucleus assay is an important technique used to evaluate genotoxic damage of chemical or physical agents (as ionizing radiations) on cells, based on quantification of cells bearing micronuclei, which are fragments derived from damage (breakage) of the DNA. Currently, this technique was updated to an automated approach that relies on plasma membrane dissolution to analyze fluorescent dye-labelled nuclei and micronuclei by flow cytometry. Cell suspensions were irradiated in PBS by a 60Co source in doses between 0 and 16 Gy, and incubat-ed by 72h. Cell membranes were lysed in the presence of SYTOX Green and EMA dyes, so EMA-stained nuclei could be discriminated as from dead cells, and nuclei and micronuclei could be quantified. Amounts of micronu-clei (percent of events) in the samples, were found to be proportional to radiation doses, and could be fitted to a linear-quadratic model (R² = 0.993). Only higher doses (8 and 16 Gy) and positive control could induce relevant increases in micronucleus amounts. The incorporation EMA showed an increase in irradiated cells. Mid- to high doses (4, 8 and 16 Gy) induced reduction of cell proliferation. Experiments showed the suitability of the tech-nique to replace traditional microscopy analysis in evaluation of the effects of ionizing radiations on cells, with possibility to use in biological dosimetry.

    Palavras-Chave: cell flow systems; cho cells; cell proliferation; cobalt 60; cell membranes; dosimetry; radiation doses; radiation effects; cell nuclei; gamma radiation

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  • IPEN-DOC 25841

    VIEIRA, LUDMILA C. ; ARAUJO, LEANDRO G. de; FERREIRA, RAFAEL V. de P.; SILVA, EDSON A. da; CANEVESI, RAFAEL L.S.; MARUMO, JULIO T. . Uranium biosorption by Lemna sp. and Pistia stratiotes. Journal of Environmental Radioactivity, v. 203, p. 179-186, 2019. DOI: 10.1016/j.jenvrad.2019.03.019

    Abstract: Biosorption-based technologies have been proposed for the removal of radionuclides from radioactive liquid waste containing organic compounds. Nevertheless, pytoremediation potential of uranium (U) by nonliving aquatic macrophytes Lemna sp. and Pistia stratiotes has not been previously addressed. In this study, uranium biosorption capacity by Pistia stratiotes and Lemna sp. was evaluated by equilibrium and kinetics experiments. The biomasses were added to synthetic and real waste solutions. The assays were tested in polypropylene vials containing 10 mL of uranium nitrate solution and 0.20 g of biomass. Solutions ranging from 0.25 to 84.03 mmol l−1 were employed for the assessment of uranium concentration in each macrophyte. The equilibrium time was 1 h for both macrophytes. Lemna sp. achieved the highest sorption capacity with the use of the synthetic solution, which was 0.68 mmol g−1 for the macrophyte. Since Lemna sp. exhibit a much higher adsorption capacity, only this biomass was exposed to the actual waste solution, being able to adsorb 9.24×10−3 mmol g−1 U (total). The results show that these materials are potentially applicable to the treatment of liquid radioactive waste.

    Palavras-Chave: sorption; uranium; biomass; adsorption; organic compounds; aquatic ecosystems; plants; radioactive wastes

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  • IPEN-DOC 25840

    APPANNABABU, S.; LICHTENTHALER, R.; ALVAREZ, M.A.G.; RODRIGUEZ-GALLARDO, M.; LEPINE-SZILY, A.; PIRES, K.C.C.; SANTOS, O.C.B.; SILVA, U.U.; FARIA, P.N. de; GUIMARÃES, V.; ZEVALLOS, E.O.N.; SCARDUELLI, V.; ASSUNÇÃO, M.; SHORTO, J.M.B. ; BARIONI, A.; ALCANTARA-NUNEZ, J.; MORCELLE, V.. Two-neutron transfer in the He-6 + Sn-120 reaction. Physical Review C, v. 99, n. 1, p. 014601-1 - 014601-7, 2019. DOI: 10.1103/PhysRevC.99.014601

    Abstract: A large yield of α particles produced in the 120Sn(6He, α) reaction was measured at 20.3-, 22.2-, 22.4-, and 24.5-MeV bombarding energies. The α particles are distributed over a broad energy range in the vicinity and below the elastic scattering 6He peak. Energy integrated α-particle cross sections have been obtained at θlab = 36◦, 40◦, and 60◦. The α energy distributions have been analyzed at a fixed laboratory angle (≈60◦) in terms of the reaction Q value, considering the 2n-transfer reaction kinematics 120Sn(6He, α)122Sn. A kinematical analysis of the Q-value distribution shows that the recoil system 120Sn + 2n is formed in highly excited states in the continuum, at increasing excitation energies as the bombarding energy increases. It is shown that by using Brink’s formula, the excitation energy depends on the transferred angular momentum following a linear relation with the square of the angular momentum, indicating that some kind of dinuclear rotating system is formed after the reaction.

    Palavras-Chave: two-nucleon transfer reactions; neutron transfer; alpha particles; helium 6 reactions; tin 120 reactions; nuclear reactions; radioactive ion beams

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  • IPEN-DOC 25839

    ESPOSITO, VINCENZO; KABIR, AHSANUL; ROSA, MASSIMO; NONG, NGO V.; RODRIGUES, THENNER S. ; RODRIGUES, LAYS N. ; MACHADO, MARINA F.S. ; MORAES, LETICIA P.R. ; MARANI, DEBORA; FONSECA, FABIO C. . Tuning diffusion paths in shaped ceria nanocrystals. CrystEngComm, v. 21, n. 27, p. 4025-4029, 2019. DOI: 10.1039/c9ce00414a

    Abstract: Mass diffusion controls material structuring from the atomic to the macro-scale defining properties and functionalities. We show here that surface energy in Ce0.9Gd0.1O3-d shaped nanocrystals, i.e. nanocubes, nanorods and spherical nanoparticles, can control solid state diffusion mechanisms over a long range, leading to extreme microstructural diversity.

    Palavras-Chave: nanostructures; crystals; cerium oxides; diffusion; gadolinium; doped materials

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  • IPEN-DOC 25838

    COURROL, DANIELLA dos S.; LOPES, CARLA R.B.; PEREIRA, CAMILA B.P.; FRANZOLIN, MARCIA R.; SILVA, FLAVIA R. de O. ; COURROL, LILIA C.. Tryptophan silver nanoparticles synthesized by photoreduction method: characterization and determination of bactericidal and anti-biofilm activities on resistant and susceptible bacteria. International Journal of Tryptophan Research, v. 12, p. 1-8, 2019. DOI: 10.1177/1178646919831677

    Abstract: The high rates of antibiotics use in hospitals have resulted in a condition where multidrug-resistant pathogens have become a severe threat to the human health worldwide. Therefore, there is an increasing necessity to identify new antimicrobial agents that can inhibit the multidrugresistant bacteria and biofilm formation. In this study, antibacterial and anti-biofilm activities of tryptophan silver nanoparticles (TrpAgNP) were investigated. The TrpAgNPs were synthesized by photoreduction method, and the influence of irradiation time and concentration of reagents were analyzed. The nanoparticles were characterized by transmission electron microscopy, Zeta Potential and (UV)-absorption spectra. The antibacterial activity of TrpAgNPs was tested for antibiotic-resistant and susceptible pathogens, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Citrobacter freundii, Klebsiella pneumoniae, Salmonella typhimurium, and Pseudomonas aeruginosa, evaluating the influence of photoreduction parameters in bactericidal effect. The results have shown that TrpAgNPs solutions with lower tryptophan/silver nitrate (AgNO3) ratio and higher AgNO3 concentration have higher bactericidal action against bacteria with inhibition of ~100% in almost all studied bacterial strains. The antimicrobial activity of TrpAgNPs within biofilms generated under static conditions of antibiotic-resistant and susceptible strains of S. aureus, S. epidermidis, E. coli, K. pneumoniae, C. freundii, and P. aeruginosa was also investigated. The results showed that TrpAgNPs have an inhibitory effect against biofilm formation, exceeding 50% in the case of Gram-negative bacteria (E. coli, K. pneumoniae, C. freundii, and P. aeruginosa—54.8% to 98.8%). For Gram-positive species, an inhibition of biofilm formation of 68.7% to 72.2 % was observed for S. aureus and 20.0% to 40.2% for S. epidermidis.

    Palavras-Chave: antimicrobial agents; silver; antibiotics; tryptophan; nanoparticles; irradiation; photosynthetic bacteria; photochemical reactions

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  • IPEN-DOC 25837

    ROSA, JORGE M. ; GARCIA, VANESSA S.G. ; BOIANI, NATHALIA F. ; MELO, CAMILA G. ; PEREIRA, MARIA C.C. ; BORRELY, SUELI I. . Toxicity and environmental impacts approached in the dyeing of polyamide, polyester and cotton knits. Journal of Environmental Chemical Engineering, v. 7, n. 2, p. 1-7, 2019. DOI: 10.1016/j.jece.2019.102973

    Abstract: Three colouration process was analyzed, in which consumption of water, the spent of electrical and thermal energy, emission of carbon dioxide besides effluent toxicity of dyeing of polyamide, cotton and polyester knits were approached. the dyeing of polyamide knit presented lowest consumption of electrical energy, the dyeing of polyester knit presented the lowest consumption of thermal energy and emission of co2 molecules into atmosphere, and the effluent of cotton dyeing presented lowest acute toxicity (CE50) to Daphnia similis.

    Palavras-Chave: toxicity; dyes; cotton; textiles; polyamides; polyesters; energy consumption; environmental impacts; water requirements; thermal energy storage equipment; brazil; pollutants; textile industry; waste water; daphnia

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  • IPEN-DOC 25836

    CANO, NILO F.; RAO, T.K.G.; AYALA-ARENAS, JORGE S.; GONZALES-LORENZO, CARLOS D.; OLIVEIRA, LETICIA M. ; WATANABE, SHIGUEO. TL in green tourmaline: study of the centers responsible for the TL emission by EPR analysis. Journal of Luminescence, v. 205, p. 324-328, 2019. DOI: 10.1016/j.jlumin.2018.09.034

    Abstract: Electron paramagnetic resonance (EPR) studies have been carried out to identify the defect centers responsible for the thermoluminescence (TL) peaks in the mineral tourmaline. The mineral exhibits three TL peaks approximately at 170, 250 and 310 °C. The EPR spectrum of the green tourmaline sample pre-heated to 500 °C presented a large signal around g=4.3 due to Fe3+ ion. Room temperature EPR spectrum of irradiated green tourmaline shows the formation of two defect centers in the region of g=2.0. One of the centers (center II) with a g factor equal to 1.96 is identified as an F+-center and is related to the observed high temperature 250 and 310 °C TL peaks. Center I exhibiting a doublet is due to hydrogen atoms (H0), stable in the crystal lattice at room temperature and this center correlates with the TL peak at 170 °C of the green tourmaline. An optical absorption measurement also was carried out. Bands at around 430, 730 and 1100 nm have been observed.

    Palavras-Chave: thermoluminescence; electron spin resonance; tourmaline; silicate minerals; dosimetry; radiation doses; crystal structure

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  • IPEN-DOC 25835

    MURATA, CAMILA H.; HONDA, CRISTIANE J.C. ; LAVINIA, NICOLAS C.; CALDAS, LINDA V.E. ; MEDEIROS, REGINA B.. The performance of a prototype device designed to evaluate quality parameters of radiological equipment: complementary study. Radiation Physics and Chemistry, v. 159, p. 131-137, 2019. DOI: 10.1016/j.radphyschem.2019.02.034

    Abstract: Quality control measurements in radiological equipment are essential to verify their achievable performance standards, as average peak voltage (kVp), practical peak voltage (kVpp), exposure time, radiation dose and halfvalue layer (HVL). In a recent study, a multifunctional prototype's partial results were presented using a solidstate detector to evaluate quality parameters as kVp, exposure time and HVL of radiological equipment. In the present work, the accuracy of these measurements was improved, and dosimetric parameters were developed aiming to comply with normative requirements. The prototype board hardware was built with four sensors PIN RD100 A and a dedicated software based on their signals. In a single exposure, these signals were used in settled polynomial functions to determine kVp, kVpp, exposure time, radiation dose, dose rate and HVL. Characterization tests were undertaken at an instruments calibration laboratory and at a clinical research laboratory. A mathematical function was fitted for 50–120 kVp range, with R2 =0.999. This new algorithm allowed improving the kVp accuracy from [0.3–2.3%] to [0.03–1.5%]. The reproducibility and accuracy of the radiation dose rate reached 0.94% and 0.34%, respectively. The dose range measurements varied from 0.01 to 40 mGy. In addition, calibration tests were performed in calibration laboratory at standard traceable radiation qualities of RQR6 and RQR8. The total uncertainty associated with this calibration did not exceed 2%. In conclusion, the prototype can be considered a multifunctional non-invasive instrument appropriate to evaluate radiological equipment performance with an effective range from 50 kV to 120 kV.

    Palavras-Chave: radiology; equipment; quality control; performance; x-ray equipment; accuracy; photodiodes; comparative evaluations; quantum efficiency

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  • IPEN-DOC 25834

    DONATUS, UYIME ; KLUMPP, RAFAEL E. ; MOGILI, NAGA V.V.; ANTUNES, RENATO A.; MILAGRE, MARIANA X. ; COSTA, ISOLDA . The effect of surface pretreatment on the corrosion behaviour of silanated AA2198‐T851 Al‐Cu‐Li alloy. Surface and Interface Analysis, v. 51, n. 2, p. 275-289, 2019. DOI: 10.1002/sia.6584

    Abstract: The corrosion behaviour of silanated AA2198‐T851 alloy substrates with and with no manufacturing‐process induced near‐surface deformed layer (MPI‐NSDL) has been investigated. Two methods (alkaline etching + desmutting and mechanical polishing) were employed in removing the MPI‐NSDL. Silanization was performed using 2‐bistriethoxysilylethane. Electrochemical impedance spectroscopy (EIS), salt spray test, and microscopy techniques were employed in the investigation of the corrosion behaviours. The studies revealed that polishing appeared to be the best silanating pre‐treatment (compared with degreasing and etching + desmutting) for the new generation AA2198‐T851 Al‐Cu‐Li alloy, and this was reflected in the EIS spectra. The etched + desmutted and the degreased surface with MPI‐NSDL did not respond well to silanization and presented more pitting sites per square millimeter. However, the severity of corrosion per pit was more on the polished sample compared with the other two. Also, the corrosion mechanisms were different for the three cases.

    Palavras-Chave: corrosion; aluminium alloys; copper alloys; corrosion protection; lithium alloys; surface treatments; microstructure; silanes; corrosion resistant alloys

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  • IPEN-DOC 25833

    CASTRO, MICHELE C.B. de ; COUTO, ANTONIO A. ; ALMEIDA, GISELE F.C. ; MASSI, MARCOS; LIMA, NELSON B. de ; SILVA SOBRINHO, ARGEMIRO da; CASTAGNET, MARIANO ; XAVIER, GLEICY L. ; OLIVEIRA, RENE R. . The effect of plasma nitriding on the fatigue behavior of the Ti-6Al-4V alloy. Materials, v. 12, n. 3, p. 1-13, 2019. DOI: 10.3390/ma12030520

    Abstract: The Ti-6Al-4V alloy is widely used in the manufacture of components that must have low density and high corrosion resistance and fatigue strength. The fatigue strength can be improved by surface modification. The aim of this study was to determine the influence of plasma nitriding on the fatigue behavior of a Ti-6Al-4V alloy with a lamellar microstructure (Widmanstätten type). Nitriding was executed at 720 C for 4 h in an atmosphere with N2, Ar, and H2. Microstructure characterization of the samples was carried out by X-ray diffraction analysis, optical microscopy, and scanning electron microscopy. The average roughness of the specimens was determined, and fatigue tests were executed in a bending–rotating machine with reverse tension cycles (R = 􀀀1). X-ray diffraction analysis of the nitrided alloy revealed the following matrix phases: , , "-Ti2N, and -TiN. A nitrogen diffusion layer was formed between the substrate and the titanium nitrides. Plasma nitriding resulted in an increase in low-cycle fatigue strength, whereas at high cycles of 200 MPa, both conditions exhibited similar behaviors. The fracture surface of the fatigue-tested specimens clearly revealed the lamellar microstructure. The fracture mechanism in the non-nitrided specimens appears to be due to cracking at the interface of the and phases of the lamellar microstructure.

    Palavras-Chave: titanium alloys; aluminium alloys; vanadium alloys; plasma; nitridation; thermochemical processes; fatigue

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  • IPEN-DOC 25832

    DONATUS, UYIME ; ARAUJO, JOAO V. de S. ; MACHADO, CARULINE de S.C. ; MOGILI, NAGA V.V.; ANTUNES, RENATO A.; COSTA, ISOLDA . The effect of manufacturing process induced near-surface deformed layer on the corrosion behaviour of AA2198-T851 Al–Cu–Li alloy. Corrosion Engineering, Science and Technology, v. 54, n. 3, p. 205-215, 2019. DOI: 10.1080/1478422X.2018.1558932

    Abstract: The effect of the near-surface deformed layer on the corrosion behaviour of AA2198-T851 Al–Cu–Li alloy has been investigated using microscopy and electrochemical techniques. This shows that a deformed layer developed by rolling was more active but only exhibited superficial attack compared to a mechanically polished surface, which produced severe localised corrosion associated with the presence of hexagonal T1 particles. The rolled surface became increasingly corrosion resistant with time, but when coupled, galvanically enhanced severe localised corrosion sites developed on the surface over time.

    Palavras-Chave: corrosion; microstructure; transmission electron microscopy; metals; alloys; scanning electron microscopy; surfaces; interfaces; aluminium alloys; copper alloys; corrosion protection; lithium alloys

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  • IPEN-DOC 25831

    SILVA, JULIO C.M.; NTAIS, SPYRIDON; RAJARAMAN, VISHWANATHAN; TEIXEIRA-NETO, ERICO; TEIXEIRA-NETO, ANGELA A.; NETO, ALMIR O. ; ANTONIASSI, RODOLFO M. ; SPINACE, ESTEVAM V. ; BARANOVA, ELENA A.. The catalytic activity of Pt:Ru nanoparticles for ethylene glycol and ethanol electrooxidation in a direct alcohol fuel cell. Electrocatalysis, v. 10, n. 3, p. 203-213, 2019. DOI: 10.1007/s12678-019-00515-8

    Abstract: In this study, we investigated the carbon-supported PtRu nanoparticles with atomic ratios of Pt:Ru of 100:0, 90:10, 70:30, and 50:50 for ethanol and ethylene glycol electrooxidation in alkaline media. The nanoparticles were synthesized using sodium borohydride method with 20 wt% of metals loading on carbon. The nanoparticle mean sizes were 7.3 nm, 5.7 nm, 5.2 nm, and 5.1 nm for Pt/C, Pt90Ru10/C, Pt70Ru30/C, and Pt50Ru50/C, respectively. X-ray diffraction (XRD) analysis revealed that Pt and PtRu electrocatalysts have face-centered cubic (fcc) structure and suggests the alloy formation for all PtRu/C materials, which was further supported by the X-ray photoelectron spectroscopy (XPS). Based on XPS analysis, Pt50Ru50/C has higher amount of Pt oxides on the surface than Pt70Ru30/C. Electrochemical results demonstrated that the addition of Ru to Pt enhances the catalytic activity towards ethanol and ethylene glycol electrooxidadion. The catalyst of Pt50Ru50/C composition showed the lowest onset potential for ethanol and ethylene glycol electrooxidation, which were 160 and 70 mV lower than for Pt/C, respectively. Furthermore, this catalyst outperformed Pt/C and other PtRu/C compositions in chronoamperometric and direct alcohol fuel cell (DAFC) experiments. DAFC experiments using Pt50Ru50/C as anode had the power density 40 and 14% higher than using Pt/C for ethanol and ethylene glycol, respectively. The promotion is due to the bi-functional mechanism and/or electronic effect of two metals in the alloy.

    Palavras-Chave: nanoparticles; electrocatalysts; oxidation; ethanol; ethylene glycols; electrochemical corrosion; fuel cells; direct ethanol fuel cells

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  • IPEN-DOC 25830

    SCIANI, JULIANA M.; NEVES, ADRIANA; VASSÃO, RUTH C.; SPENCER, PATRICK ; ANTONIAZZI, MARTA M.; JARED, CARLOS; PIMENTA, DANIEL C.. The amphibian diacylglycerol O-acyltransferase 2 (DGAT2): a ‘paleoprotein’ with conserved function but unique folding. Protein Journal, v. 38, n. 1, p. 83-94, 2019. DOI: 10.1007/s10930-019-09814-x

    Abstract: Amphibians are, currently, considered the first vertebrates that had performed the aquatic to terrestrial transition during evolution; therefore, water balance and dehydration control were prerequisites for such environment conquering. Among anurans, Phyllomedusa is a well-studied genus, due to its peptide-rich skin secretion. Here, we have analyzed the skin secretion of Phyllomedusa distincta targeting the proteins present in the skin secretion. The major soluble protein was chromatographically isolated and utilized to immunize rabbits. Through proteomics approaches, we were able to identify such protein as being the diacylglycerol O-acyltransferase 2 (DGAT2), a crucial enzyme involved in lipid synthesis and in the skin water balance. Immunohistochemistry assays revealed the protein tissular distribution for different animal species, belonging to different branches of the phylogenetic tree. Specifically, there was positivity to the anti-DGAT2 on Amphibians’ skin, and no antibody recognition on fish and mammals’ skins. The DGAT2 multiple sequence alignment reveals some degree of conservation throughout the genera; however, there is a different cysteine pattern among them. Molecular modeling analyses corroborate that the different cysteine pattern leads to distinct 3D structures, explaining the different antibody recognition. Moreover, the protein phylogenetic analyses place the Xenopus DGAT2 (the available amphibian representative) next to the Coelacanthus enzyme, which have led the authors to term this a ‘paleo-protein’. DGAT2 would be, therefore, an ancient protein, crucial to the terrestrial environment conquest, with a unique folding—as indicated by the molecular models and immunohistochemistry analyses—a consequence of the different cysteine pattern but with conserved biological function.

    Palavras-Chave: amphibians; peptides; skin; proteins; secretion; chemical analysis; temperature control

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  • IPEN-DOC 25829

    LOPES, FABIO J.S. ; SILVA, JONATAN J. ; MARRERO, JUAN C.A.; TAHA, GHASSAN; LANDULFO, EDUARDO . Synergetic aerosol layer observation after the 2015 Calbuco volcanic eruption event. Remote Sensing, v. 11, n. 2, p. 1-22, 2019. DOI: 10.3390/rs11020195

    Abstract: On 22 April 2015, the Calbuco volcano in Chile (Lat: 41.33 S, Long: 72.62 W) erupted after 43 years of inactivity followed by a great amount of aerosol injection into the atmosphere. The pyroclastic material dispersed into the atmosphere posed a potential threat to aviation traffic and air quality over affected a large area. The plumes and debris spread from its location to Patagonian and Pampean regions, reaching the Atlantic and Pacific Oceans and neighboring countries, such as Argentina, Brazil and Uruguay, driven by the westerly winds at these latitudes. The presence of volcanic aerosol layers could be identified promptly at the proximities of Calbuco and afterwards by remote sensing using satellites and lidars in the path of the dispersed aerosols. The Cloud-Aerosol Lidar and Pathfinder Satellite Observations (CALIPSO), Moderate Resolution Imaging Spectroradiometer (MODIS) on board of AQUA/TERRA satellites and Ozone Mapping and Profiler Suite (OMPS) on board of Suomi National Polar-orbiting Partnership (Suomi NPP) satellite were the space platforms used to track the injected layers and a multi-channel lidar system from Latin America Lidar Network (LALINET) SPU Lidar station in South America allowed us to get the spatial and temporal distribution of Calbuco ashes after its occurrence. The SPU lidar stations co-located Aerosol Robotic Network (AERONET) sunphotometers to help in the optical characterization. Here, we present the volcanic layer transported over São Paulo area and the detection of aerosol plume between 18 and 20 km. The path traveled by the volcanic aerosol to reach the Metropolitan Area of São Paulo (MASP) was tracked by CALIPSO and the aerosol optical and geometrical properties were retrieved at some points to monitor the plume evolution. Total attenuated backscatter profile at 532 nm obtained by CALIPSO revealed the height range extension of the aerosol plume between 18 and 20 km and are in agreement with SPU lidar range corrected signal at 532 nm. The daily evolution of Aerosol Optical Depth (AOD) at 532 and 355 nm, retrieved from AERONET sunphotometer, showed a substantial increasing on 27 April, the day of the volcanic plume detection at Metropolitan Area of São Paulo (MASP), achieving values of 0.33 0.16 and 0.22 0.09 at 355 and 532 nm, respectively. AERONET aerosol size distribution was dominated by fine mode aerosol over coarse mode, especially on 27 and 28 April. The space and time coincident aerosol extinction profiles from SPU lidar station and OMPS LP from the Calbuco eruption conducted on 27 April agreed on the double layer structure. The main objective of this study was the application of the transmittance method, using the Platt formalism, to calculate the optical and physical properties of volcanic plume, i.e., aerosol bottom and top altitude, the aerosol optical depth and lidar ratio. The aerosol plume was detected between 18 and 19.3 km, with AOD value of 0.159 at 532 nm and Ånsgtröm exponent of 0.61 0.58. The lidar ratio retrieved was 76 27 sr and 63 21 sr at 532 and 355 nm, respectively. Considering the values of these parameters, the Calbuco volcanic aerosol layers could be classified as sulfates with some ash type.

    Palavras-Chave: volcanoes; ashes; aerosols; boundary layers; atmospheric circulation; optical radar; south america; air quality

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  • IPEN-DOC 25828

    BETINI, E.G. ; GOMES, M.P. ; MILAGRE, M.X. ; MACHADO, C.S.C. ; REIS, L.A.M. ; MUCSI, C.S. ; ORLANDO, M.T.D.; LUZ, T.S.; MARTINEZ, L.G. ; ROSSI, J.L. . Study on welding thermal cycle and residual stress of UNS S32304 duplex stainless steel selected as external shield for a transport packaging of Mo-99. Brazilian Journal of Radiation Sciences, v. 7, n. 2A, p. 1-13, 2019. DOI: 10.15392/bjrs.v7i2A.679

    Abstract: Thin plates of duplex stainless steel UNS S32304 were welded using the pulsed gas tungsten arc GTAW process (butt joint) without filler addition. The used shielding gas was pure argon and 98% argon plus 2% of nitrogen. The thermal cycles were acquired during welding, in regions near the melting pool. This alloy is candidate for the external clad of a cask for the transport of high activity radiopharmaceuticals substances. For the residual stress measurements in austenite phase an X-ray diffractometer was used in a Bragg-Brentano geometry with CuKα radiation (λ= 0.154 nm) and for ferrite phase was used a pseudo-parallel geometry with CrKα radiation (λ= 0.2291nm). The results of residual stress using sin2 methodology showed that the influence of the high welding temperature leads to compressive stresses for both phases of the duplex steels mainly in the heat-affected zone. It was observed a high temperature peak and an increase of the mean residual stress after addition of ni-trogen to the argon shielding gas.

    Palavras-Chave: thermal cycling; molybdenum 99; containers; gas tungsten-arc welding; nitrogen; residual stresses; stainless steels; temperature range 0400-1000 k; x-ray diffractometers; radioactive materials

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  • IPEN-DOC 25827

    PUGLIESI, REYNALDO ; PEREIRA, MARCO A.S. ; ANDRADE, MARCOS L.G. ; BASSO, JULIANA M.L.; VOLTANI, CIBELE G.; GONZALES, IVONE C.. Study of the fish fossil Notelops brama from Araripe-Basin Brazil by Neutron Tomography. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, v. 919, p. 68-72, 2019. DOI: 10.1016/j.nima.2018.12.001

    Abstract: 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.

    Palavras-Chave: tomography; fossils; fishes; paleontology; neutron beams; brazil; brazilian cnen

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ATENÇÃO!

ESTE TEXTO "AJUDA" ESTÁ SUJEITO A ATUALIZAÇÕES CONSTANTES, A MEDIDA QUE NOVAS FUNCIONALIDADES E RECURSOS DE BUSCA FOREM SENDO DESENVOLVIDOS PELAS EQUIPES DA BIBLIOTECA E DA INFORMÁTICA.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.

O Repositório Digital do IPEN é um equipamento institucional de acesso aberto, criado com o objetivo de reunir, preservar, disponibilizar e conferir maior visibilidade à Produção Científica publicada pelo Instituto, desde sua criação em 1956.

Operando, inicialmente como uma base de dados referencial o Repositório foi disponibilizado na atual plataforma, em junho de 2015. No Repositório está disponível o acesso ao conteúdo digital de artigos de periódicos, eventos, nacionais e internacionais, livros, capítulos, dissertações, teses e relatórios técnicos.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.