Reposiório IPEN: Recent submissions

  • IPEN-DOC 24944

    FONSECA, DANIELA P.M. da ; MONTEIRO, WALDEMAR A. . Microstructural analysis of composite Cu-Cr-Ag-(CeO2, Al2O3) processing by powder metallurgy. Acta Microscópica, v. 26, B, p. 280-281, 2017.

    Abstract: Copper has long been used by mankind, since the 20th century they have gained industrial and technological importance [1]. They can be combined with ceramic materials in the synthesis of modern composites, optimized and with balanced properties [2]. The studied composite has a metal as a matrix (copper or copper, chromium and silver), the ceramic oxide as the reinforcing phase (ceria or alumina) and was synthesized by powder metallurgy. A possible application of this material is like anodes in Solid Oxide Fuel Cells (SOFC), cermets based on rare earth oxides and metals such as copper, silver and nickel have been studied in this component [3]. The objective of this work was the analysis of the particle size by SEM and chemical composition by EDS of the starting material (powders of copper, chromium, silver, ceria and alumina) and the microstructural characterization by MO of copper composites with four compositions: (a) 80% Cu – 8% Cr – 4% Ag – 8% CeO2; (b) 80% Cu – 20% CeO2; (c) 80% Cu – 8% Cr – 4% Ag – 8% Al2O3; (d) 80% Cu – 20% Al2O3. For analysis in the SEM/EDS the powders were fixed in the sample port with carbon paint, for the powders of ceria and alumina was made gold coating for 2 min. The copper powder presented nodular agglomerates; the chromium powder presented large particles with coarse contours and irregular shape; the silver powder presented a dendritic shape; the ceria powder presented very small particles and it was not possible to observe them due to the limitation of the SEM and the alumina powder presented flake-shaped agglomerates, figure 1. The EDS microanalysis results for copper, silver, ceria and alumina powders were adequate, for chromium powder indicated silicon and iron (manufacturer predicted) and calcium impurities (not predicted but with low percentage), figure 1. The powders were weighed on a precision balance (according to each composition), mixed manually and cold-compacted in uniaxial press with 180 MPa pressure and sintered in a tubular furnace with vacuum of 10-7 torr, temperature of 750 °C and time of 6 h. The samples were obtained in laboratory scale with a 31x12x 3.5 mm parallelepipedal shape, hot mounting, grinded (240, 320, 400, 600, 800) and polished (3μm and 1μm diamond and 0.02 μm silica). The optical micrographs indicated coalescence of copper particles, homogeneity, porosity and an unknown (black) phase, possibly related to ceramic materials, figure 2. The sample (c) was the only one that presented different microstructure between the normal and transverse directions, possibly due to segregation of the powders during mixing. It was possible to make an adequate analysis of the particle formats of the copper, chromium, silver and alumina powders; however, the ceria powder needs to be analyzed again in SEM with higher capacity of increase. The results of EDS microanalysis were promising for all powders. The optical micrographs suggest a good adequacy of the compaction and sintering parameters, forming a homogeneous microstructure and with the desired porosity, except for sample (c), that the mixture was not suitable. In order to study the formed phases it is necessary to perform an X-ray mapping on SEM and X-ray diffraction in the samples after sintering.

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  • IPEN-DOC 24943

    FAUSTINO, MAINARA G. ; MONTEIRO, LUCILENA R. ; SILVA, TATIANE B. de S.C. da ; STELLATO, THAMIRIS B. ; SOARES, SABRINA M.V. ; MARQUES, JOYCE R. ; COTRIM, MARYCEL E.B. ; PIRES, MARIA A.F. . Total metals in stormwater runoff at the Nuclear and Energy Research Institute (IPEN), São Paulo – Brazil. In: SAFETY, HEALTH AND ENVIRONMENT WORLD CONGRESS, 17th, July 09-12, 2017, Vila Real, Portugal. Proceedings... 2017. p. 17-21. DOI: 10.14684/SHEWC.17.2017.17-21

    Abstract: Stormwater quality allows to evaluate if any pollutants load happens within its runoff. This work aims stormwater temporal and spatial profile characterization to assess environmental risk and to identify chemical tracers. Thus, a specific collector was built to sample collection, with four separate PVC tubes, and the collector allowed single event temporal and sequential evaluation, as long as each compartment was fulfilled. The collector was installed in the runoff direction in order to have maximum collection volume. Two collections were carried out in summer (January 2017) at two IPEN stations, in urban areas. Total metals analysis were performed, in addition to physicochemical data, such as pH, temperature and conductivity. The results had aluminum, iron and manganese present, and some elements, such as zinc, had a temporal distribution, with a decrease concentration within the collected volume. The preliminary results have as objective to assist the studies of urban water management.

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  • IPEN-DOC 24942

    FARIAS, WELLINGTON M. ; SIMONE, LUIZ R.L.; AMARAL, VANESSA S.; SCAPIN, MARCOS A. ; SILVA, PAULO S.C. . Utilização de elementos terras raras para estudo da composição de conchas de ostras do genero crassostrea / Use of rare earth elements for the composition study of Crassostrea gender oyster shells. In: CONGRESSO BRASILEIRO DE GEOQUIMICA, 16., 22-25 de agosto, 2017, Búzios, RJ. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Geoquímica, 2017.

    Abstract: Foram determinadas as concentrações de elementos terras rara e dos elementos maiores (Ca, Si, P, S, Cl e Sr) em amostras de conchas de ostras das espécies Crassostrea mangle e Crassostrea brasiliana provenientes de diversas regiões do Brasil. Foi feita uma normalização por meio do fator de enriquecimento utilizando o La como elemento conservativo e a concentração dos elementos na água do mar como normalizador. Verificou-se que as razões elementares normalizadas apresentam boa correlação entre si e que esta normalização permite separar as amostras de acordo com o ambiente em estas se formaram.

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  • IPEN-DOC 24941

    LAPA, N.S.; PEREIRA, L.C.M.; MADEIRA, A.A.; WELLELE, O.J.M.; SABUNDJIAN, G.; LEE, S.M. ; ARO, I.; STEINROTTER, T.; VARELA, J.G.; VALKONEN, J.; PILJUGIN, G.R.S.; FURIERI, E.; RODRIGUEZ, J.. Support to the nuclear safety regulator of Brazil (CNEN) through an INSC project. In: EUROSAFE FORUM, November 6-7, 2017, Paris, FR. Proceedings... Fontenay-aux-Roses, France: Institut de Radioprotection et de Sûreté Nucléaire, 2017. p. 21-36.

    Abstract: The paper introduces the European Union funded cooperation between the Brazilian nuclear regulatory body (CNEN) and a consortium of several European organizations. The still ongoing cooperation started in 2011 and has provided CNEN with insights and complementary information for licensing and regulatory activities on different reactor nuclear safety issues. The support is described by examples relating to the Severe Accident Management Program (SAMP) of the Angra 2 nuclear power plant NPP and the safety of digital instrumentation and control systems (DI&C) of Angra 3. The goal of the support regarding the SAMP is the review of the SAMP - under the licensing process by CNEN – with the focus on the new procedures and equipment implemented after the Fukushima accident. In parallel, a MELCOR simulation model of Angra 2 has been developed to perform independent calculations in order to support the assessment of the safety analysis presented in the Angra 2 Severe Accident Management Guides (SAMG). The support regarding DI&C is focused on regulatory issues concerning the review and assessment of digital instrumentation and control systems (DI&C) of the Angra 3 NPP under the licensing process by CNEN – providing CNEN with insights and complementary information on licensing experiences of new reactors with a DI&C architecture and technology similar to that of the Angra 3 NPP.

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  • IPEN-DOC 24940

    SANTANA, JULYANA G. ; GUVEN, OLGUN; MOURA, ESPERIDIANA A.B. . Propriedades térmicas e mecânicas de filmes flexíveis de polietileno e copolímero de etileno e álcool vinílico reforçados com óxido de grafeno / Thermal and mechanical properties of flexible films of polyethylene and ethylene vinyl alcohol reinforced with graphene oxide. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 1797-1802.

    Abstract: Os copolímeros de etileno e álcool vinílico (EVOH) são uma família de resinas com excelentes propriedades de barreira a gás de grande importância para a indústria de embalagens para alimentos, o polietileno de alta densidade (HDPE) um polímero hidrofóbico que em mistura com o EVOH, agrega melhores propriedades de barreira e mecânicas a embalagem final. O objetivo deste trabalho foi estudar os efeitos da adição de óxido de grafeno (GO) nas propriedades de filmes flexíveis preparados a partir de uma blenda HDPE e EVOH (HDPE/EVOH). Que foram processados, utilizando-se uma extrusora dupla rosca corrotante, e posteriormente os materiais processados foram alimentados a uma extrusora balão de laboratório para a obtenção dos filmes flexíveis. Os filmes flexíveis foram caracterizados por meio das análises de DSC, TG, MEV e ensaios de tração e a correlação entre as suas propriedades foi discutida.

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  • IPEN-DOC 24939

    DURAZZO, M. ; SALIBA-SILVA, A.M. ; MARTINS, I.C. ; CARVALHO, E.F.U. de ; RIELLA, H.G.. Manufacturing low enriched uranium metal by magnesiothermic reduction of UF4. In: EUROPEAN RESEARCH REACTOR CONFERENCE, March 11-15, 2018, Munich, Germany. Proceedings... Brussels, Belgium: European Nuclear Society, 2018. p. 1-12.

    Abstract: This work presents an experimental description of thermal and physical studies to attain a practical manufacturing process of uranium metal enriched to 20% U235 (LEU–Low Enriched Uranium) by metallothermic reduction of UF4, with nuclear purity, for reduced amounts (1000g of uranium). The magnesiothermic reduction is influenced by the thermal conditions for UF4 reduction. These variables are investigated. The physical arrangement of the crucible/reduction reactor/furnace system and the management of the furnace thermal input in the reduction reactor during the heating were studied. Thermal simulation experiments provided delineation for the reactants’ thermal progress before the ignition of the reaction. The heat input to the reduction system has proved to be the main variable that influenced the efficiency of the process. The levels of metallic yield and reproducibility have been improved. The typical yield in the production of uranium metal was above 80%.

    Palavras-Chave: uranium; metals; nuclear fuels; materials recovery; enriched uranium; fuels; fabrication

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  • IPEN-DOC 24938

    CAVALCANTE, A.K. ; LUGAO, A.B. ; ROGERO, J.R. ; ROGERO, S. ; MAMEDE, F.C.S. ; MAZIERO, J.S. . Ecotoxicology as a tool in nanotechnology. In: CONGRESSO DA SOCIEDADE LATINO AMERICANA DE BIOMATERIAIS, ORGAOS ARTIFICIAIS E ENGENHARIA DE TECIDOS, 14.; EDICAO DO WORKSHOP DE BIOMATERIAIS, ENGENHARIA DE TECIDOS E ORGAOS ARTIFICIAIS, 5., 20-24 de agosto, 2017, Maresias, SP. Abstract... 2017. p. 1000-1000.

    Abstract: The commercial applications of nanoparticles are diverse, such as use in the food industry, textile industry, electronics, water treatment and products used in medicine and health. The increase in the production and use of nanoparticles has caused great concern about the potential impacts and risks that these can cause to the environment and to human health. Nanoparticles can be released to the environment in a variety of ways and can reach the aquatic ecosystem and pose biota risks. Ecotoxicology is the study of the behavior and transformations of chemical agents and abiotic factors in the environment, as well as their effects on biota. The evaluation of the toxicity of chemical agents in the aquatic environment occurs by means of ecotoxicological tests. The purpose of this review was to summarize some ecotoxicological assays by addressing some concepts and data from nanoparticle ecotoxicity assays in order to demonstrate that ecotoxicological evaluation is an important tool for nanotechnology and that it has efficient methodologies for analyzing the Environmental health of aquatic ecosystems.

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  • IPEN-DOC 24937

    CASTRO, PEDRO A.A. de ; DIAS, DERLY A. ; VELOSO, MARCELO N. ; ZEZELL, DENISE M. . Biochemical evaluation of bone submitted to ionizing radiation by ATR-FTIR spectroscopy. In: CONFERENCE ON LASERS AND ELECTRO-OPTICS, May 14-19, 2017, San Jose, California, USA. Resumo expandido... Washington, DC, USA: OSA, 2017.

    Abstract: FTIR spectroscopy associated with PC-LDA was able to discriminate bone samples receiving different ionizing radiation doses (0,01 kGy, 1 kGy, 15 kGy), showing potential to the use of phosphate vibrational modes as a dose marker. OCIS codes: (170.4580) Medical optics and biotechnology – Optical diagnostics for medicine; (170.6510) Medical optics and biotechnology – Spectroscopy, tissue diagnostics; (170.1580) Medical optics and biotechnology – Chemometrics.

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  • IPEN-DOC 24979

    REIS, FABRÍCIO C. . Levantamento da entomofauna e micobiota de grãos de Phaseolus vulgaris L. e Vigna unguiculata L. tratados pelo processo de irradiação / Study of entomofauna and mycobiota in grains of Phaseolus vulgares L. and Vigna unguiculata L. treated by gamma-irradiation process . 2018. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 107 p. Orientador: Valter Arthur. DOI: 10.11606/T.85.2018.tde-03072018-084149

    Abstract: No presente trabalho realizou-se o levantamento da entomofauna e fungos associados a grãos de P. vulgares e V. unguiculata comercializados na cidade de São Paulo, avaliou-se a presença de fungos no corpo dos artrópodes identificados nas amostras de P. vulgares L. e V. unguiculata L., avaliou-se a atividade de água das amostras e estudou-se os efeitos do processo de irradiação na desinfestação de artrópodes e na redução da carga fúngica em grãos de P. vulgares e V. unguiculata. As amostras foram coletadas no comércio varejista em diferentes regiões da cidade São Paulo/SP. Foi adquirido 1 kg de 11 diferentes variedades entre P. vulgares (Branco, Bolinha, Carioca, Jalo, Preto, Rajado, Rosinha, Roxo e Vermelho) e V. unguiculata (Fradinho, Corda). As amostras foram desinfetadas em hipoclorito de sódio (0,5 %), enxaguadas em água destilada e distribuídos 10 grãos por placa de Petri em duplicata, contendo agar Batata Dextrose. As placas foram incubadas por 5 dias na temperatura de 25 ± 1°C, em incubadora (B.O.D.). O mesmo procedimento de plaqueamento foi realizado para os insetos isolados das amostras. No irradiador multipropósito 60Co IPEN/CNEN/SP as amostras foram irradiadas com doses de 5 e 10 kGy e os insetos foram submetidos a doses crescentes de 0 a 3,4 kGy. Diversos gêneros fúngicos foram isolados independentemente da variedade analisada. Foi constatada presença de fungos associados a insetos em todas as amostras analisadas. A dose recomendada para letalidade imediata e simultânea nas espécies Callosobruchus maculatus, Acanthoscelides obtectus e Zabrotes subfasciatus foi de 3,0 kGy. As doses de 5 e 10 kGy são capazes de reduzir, porém não eliminam a carga fúngica dos feijões analisados. Os valores obtidos na análise de atividade de água (Aa) situaram-se abaixo do limite ideal para crescimento fúngico diretamente nos grãos.

    Palavras-Chave: food processing; irradiation; radiodisinfestation; grain disinfestation; fungi; insects; beans; vegetables; sample preparation; sodium compounds; chlorides; gamma radiation; cobalt 60

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  • IPEN-DOC 24936

    LIMA, CASSIO ; ZEZELL, DENISE . Discrimination of healthy skin and cutaneous malignant lesions using FTIR spectra and their second derivatives: a comparative study. In: CLINICAL AND TRANSLATIONAL BIOPHOTONICS, April 3-6, 2018, Hollywood, Florida, United States. Resumo expandido... Washington, DC, USA: OSA, 2018.

    Abstract: PC-LDA statistical method was used to differentiate cutaneous tumor tissue from healthy skin. Discrimination accuracy obtained by raw FTIR spectra was 95% and by second derivatives 92%, besides identifying secondary structure of proteins and collagen.

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  • IPEN-DOC 24978

    MAPRELIAN, EDUARDO . Experimentos de perda de refrigerante total e parcial no reator IEA-R1 / Total and partial loss of coolant experiments in the IEA-R1 reactor . 2018. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 188 p. Orientador: Gaianê Sabundjian. DOI: 10.11606/T.85.2018.tde-05072018-162522

    Abstract: A segurança de instalações nucleares é uma preocupação mundial que tem crescido, sobretudo, após o acidente nuclear de Fukushima. O estudo de acidentes em reatores nucleares de pesquisa tal como o Acidente de Perda de Refrigerante (APR), considerado por muitas vezes um acidente base de projeto, é importante para garantir a integridade da instalação. O APR pode levar ao descobrimento parcial ou total do núcleo do reator e, como condição de segurança, deve-se garantir que haja a remoção do calor de decaimento dos elementos combustíveis. Esse trabalho teve o objetivo de realizar experimentos de descobrimento parcial e total no Elemento Combustível Instrumentado (ECI), construído no Instituto de Pesquisas Energética e Nucleares (IPEN), a fim de estudar os possíveis APRs em reatores de pesquisa. Uma seção de testes, denominada STAR, foi projetada e construída para simular os APRs. O ECI foi irradiado no núcleo do reator IEA-R1 (IPEN) e inserido na STAR, que ficou totalmente imersa na piscina do reator. No ECI, foram instalados termopares para medição das temperaturas do revestimento e do fluido em várias posições axiais e radiais. Foram realizados experimentos para cinco níveis de descobrimento do ECI, um total e quatro parciais, em duas condições distintas de calor de decaimento. Na análise dos resultados, verificou-se que os casos de descobrimento total foram os mais críticos, ou seja, as temperaturas do revestimento foram as maiores quando comparadas com os casos de descobrimentos parciais. Adicionalmente, foi realizada a simulação numérica de dois experimentos com o código RELAP5, cujos resultados demonstraram ótima concordância com os dos níveis experimentais, e temperaturas maiores que as experimentais. As máximas temperaturas do revestimento alcançadas em todos os experimentos ficaram bem abaixo da temperatura de empolamento do combustível, que é de 500°C. Assim, a STAR provou ser um aparato experimental seguro e confiável para a realização de experimentos de perda de refrigerante.

    Palavras-Chave: reactor accidents; loss of coolant; iear-1 reactor; research reactors; data covariances; sensitivity analysis; radiosensitivity effects; computer codes; simulation

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  • IPEN-DOC 24977

    SMITH, RICARDO B. . Bases de projeto para a automatização do sistema de garantia da qualidade em gerência de rejeitos radioativos / Project bases for the automation of a quality assurance system in radioactive waste management . 2018. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 160 p. Orientador: Roberto Vicente. DOI: 10.11606/D.85.2018.tde-29062018-144015

    Abstract: O projeto, operação e descomissionamento de uma unidade de tratamento e armazenamento de rejeitos requerem que sejam observados os requisitos regulatórios referentes à garantia da qualidade nuclear, conforme o Regulamento CNENNN1.16 "Garantia da Qualidade para a Segurança de Usinas Nucleoelétricas e Outras Instalações", da Comissão Nacional de Energia Nuclear (CNEN). Entretanto, embora a aplicação do regulamento seja obrigatória, o documento da CNEN apresenta requisitos para qualquer tipo de instalação nuclear, sendo por isso genérico e pouco detalhado em relação às ações necessárias para garantir que os requisitos mais específicos de uma unidade de tratamento e armazenamento de rejeitos sejam observados. Além disso, não existem comercialmente ferramentas informatizadas já prontas para utilização, mas somente programas para gestão de qualidade que requerem uma adaptação através da inclusão de conjuntos de dados específicos do programa de controle da qualidade de uma instalação de gestão de rejeitos, ou então o desenvolvimento de uma ferramenta personalizada. Desta forma, o objetivo deste trabalho é buscar informações que permitam o desenvolvimento de bases para um sistema informatizado de garantia da qualidade que esteja em conformidade com o regulamento da CNEN NN-1.16, e que possa vir a englobar os procedimentos específicos para uma instalação de tratamento e gestão de rejeitos radioativos.

    Palavras-Chave: radioactive waste management; quality assurance; computerized control systems; programming; nuclear facilities; nuclear power plants; reporting requirements; regulations; standardization

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  • IPEN-DOC 24976

    PEREZ, CAROLINE . Estudo sobre a determinação de elementos tóxicos (As,Cu e Hg) em amostras de biomonitores da poluição atmosférica pelo método de análise por ativação com nêutrons / A study on toxic elements (As, Cu and Hg) determinations in biomonitors of atmospheric pollution by neutron activation analysis . 2018. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 112 p. Orientador: Mitiko Saiki. DOI: 10.11606/D.85.2018.tde-23072018-092731

    Abstract: No biomonitoramento da poluição atmosférica, as determinações de elementos tóxicos têm sido de suma importância para identificação das suas fontes de emissão e dos efeitos ocasionados com a sua exposição. Consequentemente diferentes técnicas analíticas vêm sendo aprimoradas e aplicadas para essa finalidade, entre elas, a análise por ativação com nêutrons (NAA). Essa técnica apresenta vantagens para a quantificação de elementos poluentes, devido a sua capacidade de análise multielementar e a sua alta sensibilidade, precisão e exatidão dos resultados. Entretanto, nos trabalhos de biomonitoramento, a NAA não tem sido muito utilizada na determinação dos elementos tóxicos As, Cu e Hg. O objetivo deste trabalho foi estabelecer um procedimento adequado de NAA para a determinação de As, Cu e Hg em amostras de biomonitores da poluição atmosférica (liquens, bromélias e cascas de árvores). O procedimento de NAA consistiu em irradiação sob fluxo de nêutrons térmicos alíquotas de amostras juntamente aos padrões sintéticos dos elementos, seguida de espectrometria de raios gama. Foram realizados ensaios preliminares de NAA para definição das condições de irradiação e de medição para determinação desses três elementos e, para isso, foram analisados diversos materiais de referência certificados (MRCs). Os resultados de As, Cu e Hg nos MRCs demonstraram boa exatidão e precisão (HORRAT < 2 e IZscoreI < 2). Isto é, para determinação de As, foi verificado que irradiações de 1 h e tempo de decaimento de 1 d para as medições permitem obter resultados satisfatórios. O As foi encontrado em todas as espécies de biomonitores analisadas e os valores de limites de detecção foram inferiores às suas frações mássicas, demostrando que o procedimento proposto pode ser satisfatoriamente utilizado nas análises de biomonitores. Nas determinações de Cu nos MRCs, foi observado que esse elemento pode ser quantificado por meio das irradiações de 20 s e de 1 h pelas medições de 66Cu e de 64Cu, respectivamente. Entretanto, dependendo da amostra, nas irradiações de 1 h pode ocorrer a interferência da alta atividade do 24Na. Nas análises de biomonitores, os tempos de irradiação de 1 h e de decaimento de 1 d foram mais apropriados que as irradiações de curta duração de 20 s, uma vez que os dados obtidos apresentaram boa precisão e limites de detecção mais baixos que os das irradiações de 20 s. Para determinação de Hg, verificou se que não há perda desse elemento nas irradiações realizadas em invólucros ou cápsulas de polietileno. O invólucro foi escolhido devido ao seu baixo custo e a facilidade de aquisição. O tempo de irradiação de 1 h foi apropriado para evitar os problemas das interferências espectrais do 198Au e 75Se, que foram mais evidentes para 8 h de irradiação. O Hg não foi detectado em nenhum dos biomonitores analisados e os limites de detecção calculados variaram de 0,01 a 6,8 μg g-1. Pelos resultados obtidos neste trabalho, concluiu-se que o procedimento de NAA estabelecido pode ser aplicado no biomonitoramento de As, Cu e Hg da poluição aérea e cabe ainda ressaltar que esses três elementos podem ser determinados por meio de uma única irradiação de 1 h, dependendo dos teores destes elementos nas amostras.

    Palavras-Chave: arsenic alloys; copper arsenides; mercury; toxic materials; atmospheric chemistry; air pollution; air pollution monitors; biological markers; certification; neutron activation analysis

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  • IPEN-DOC 24934

    BORGES, V.F. ; GATTI, L.V. ; DOMINGUES, L.G. ; CORREIA, C.S.C. ; BASSO, L.S. ; SANTOS, R.S. ; COSTA, W.R.; CRISPIM, S.P.; MARANI, L.; PENHA, T.L.B.; PAULA, A.L.S.; GLOOR, E.U.; MILLER, J.B.; KOFLER, J.. Greenhouse gases: background concentrations in brazilian coast. In: WMO/IAEA MEETING ON CARBON DIOXIDE, OTHER GREENHOUSE GASES, AND RELATED MEASUREMENT TECHNIQUES, 19th, August 27-31, 2017, Empa Dübendorf, Switzerland. Abstract... Geneva, Switzerland: World Meteorological Organization, 2017. p. 10-10.

    Abstract: In Tropical areas, and specifically in the Atlantic Ocean, there are not enough measures on greenhouse gases (GHG), and Amazon Basin represent around 50% of the world's rainforest [1]. Understand the characteristic GHG concentrations in Tropical Global range on Atlantic Ocean is an important task for many studies to determine GHG balances. The motivation of this study was understanding better the typical background for Amazon Basin from the air masses that arrived on North and Northeast Brazilian coast, come from the Atlantic Ocean in the period 2006 to 2016. We started to collect air samples on the Brazilian coast: Arembepe/BA (ABP: 12º45’46.79”S; 38º10’08.39”W – from 2006 to 2010, 15 meters above sea-level), Salinopolis/PA (SAL: 00º36’15.03”S; 47º22’25.02”W – from 2010 to 2017, 10 m a.s.l.), Natal/RN (NAT: 05º29’22.05”S; 35º15’39.64”W 15 m a.s.l – since 2010 to December 2015, then the site moved to 05º47’42.77”S; 35º11’07.10”W, 87 m a.s.l.), Camocim/CE (CAM: 02º51’47.00”S; 40º51’36.70”W – since 2014, 21.5 m a.s.l.), and in December 2016 it was started a special place at Itarema/CE (ITA: 02º55’57.11”S; 39º50’38.49”W, 96.5 m a.s.l.), where the inlet was installed in the top of a 100 m tower in the beach. In each site, the air samples, with variable height were collected weekly by using a pair of glass flasks (2.5L) and a portable sampler. The air samples were analysed on the Greenhouse Gas Laboratory (LaGEE) at IPEN (until April 2015) and later at INPE/CCST. It was quantified the respective gases: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), sulphur hexafluoride (SF6) and carbon monoxide (CO). Results showed that each site presents seasonality when compared to Ascension Island (ASC: 07º96'67.00"S; 14º0'00.00"W, South Atlantic Ocean) and Ragged Point Barbados (RPB: 13º16'50.00"N, 59º43'20.00"W, North Atlantic Ocean) global stations. Simulations of backward trajectories by HYSPLIT model (using 240 hours) [2], allowed observing how each study site is influenced by global circulation and process like Intertropical Convergence Zone [3]. Between Jan-May, the ITCZ is below SAL and CAM latitude, influencing the air masses that arrived at sites in this period. At SAL and CAM the air masses came from both North and South Atlantic Ocean, depending on time of the year, and at NAT and ABP the air masses came from only South Atlantic Ocean. The GHG concentrations showed seasonality and sometimes periods with high concentrations. Overall, all Brazilian coast sites, showed the same increase on the GHG concentrations than global mean.

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  • IPEN-DOC 24932

    BERTOLINI, T.C.R. ; GHILHEN, S.N. ; FUNGARO, D.A. . Evaluation of pelletization methods of zeolitic material from coal ash. In: INTERNATIONAL WORKSHOP - ADVANCES IN CLEANER PRODUCTION, 6th, May 24-26, 2017, São Paulo, SP. Abstract... 2017.

    Abstract: The evaluation of different methods of pelletization of zeolitic material synthesized from coal ashes was described in this work. The coal fly ash used in the synthesis of the zeolite by alkaline hydrothermal treatment were collected in the Thermoelectric Complex Jorge Lacerda, located in the Santa Catarina State, Brazil, the largest coal burning thermoelectric complex of Latin America. The raw material and synthesized zeolite in powder form were characterized to obtain chemical composition, mineralogical composition and cation-exchange capacity. The pellets were formed by mixing of zeolitic material with one or more binders and addition of deionized water. The obtained plastic mass was molded manually in the form of spheres in the size range between 4 mm and 7 mm. Different methodologies of pelletization of zeolite material were evaluated by determining the cation exchange capacity of the obtained products, workability, physical strength and water stability. The pelletized zeolitic material obtained by the best method evaluated in this study was selected for future application as adsorbent material in the effluent treatment.

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  • IPEN-DOC 24931

    BENTO, RODRIGO T. ; SZURKALO, MARGARIDA ; CORREA, OLANDIR V. ; PILLIS, MARINA F. . Morphological characterization of S-doped TiO2 thin films. In: CONGRESSO BRASILEIRO DE APLICACOES DE VACUO NA INDUSTRIA E NA CIENCIA, 38.; WORKSHOP DE TRATAMENTO E MODIFICACAO DE SUPERFICIES, 3., 21-25 de agosto, 2017, São José dos Campos, SP. Resumo expandido... 2017. p. 96-97.

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  • IPEN-DOC 24923

    BITELLI, ULYSSES D. ; AREDES, VITOR O.G. ; MURA, LUIZ E.C. . Comissionamento: calibração das barras de controle do reator IPEN/MB-01 com o núcleo contendo elementos combustíveis tipo placa. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Novembro, 2017. (IPEN-CEN-PSE-RMB-005-00-RELT-090-00). Restrito.

    Título do projeto: RMB

    Abstract: Neste relatório apresentam-se o procedimento experimental para calibração das 4 barras de controle do novo núcleo do Reator IPEN/MB-01 contendo elementos combustíveis tipo placa[1], correlacionando reatividade com o trecho de barra retirado ou inserido do núcleo (reatividade diferencial) e por conseguinte obtendo a reatividade total inserida (valor integral das barras de controle) .

    Palavras-Chave: control elements; calibration; calibration standards; fuel elements; commissioning; reactor commissioning; ipen-mb-1 reactor; fuel plates; reactivity; neutrons

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  • IPEN-DOC 24922

    BITELLI, ULYSSES D. ; AREDES, VITOR O.G. ; MURA, LUIZ E.C. . Comissionamento: medida do coeficiente de reatividade de temperatura αiso(T) no reator IPEN/MB-01. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Dezembro, 2017. (IPEN-CEN-PSE-RMB-005-00-RELT-089-00). Restrito.

    Título do projeto: RMB

    Abstract: Neste relatório apresentam-se os procedimentos experimentais a se realizarem no comissionamento do Reator IPEN/MB-01 visando a medida do coeficiente de Reatividade de Temperatura Isotérmica, αiso (T) para o núcleo com elementos combustíveis tipo placa.

    Palavras-Chave: ipen-mb-1 reactor; commissioning; coefficient of performance; reactivity; isothermal processes; fuel elements; fuel plates

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  • IPEN-DOC 24921

    LEE, SEUNG M. . Análise do acidente severo na Usina Nuclear Angra 2 utilizando o programa MELCOR. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Junho, 2018. (IPEN-CEN-PSE-DRS-010-00-RELT-006-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: Este trabalho simula um acidente de condições estendidas de projeto na Usina Nuclear ANGRA 2, utilizando o código MELCOR. A instalação nuclear ANGRA 2 foi escolhida pelo fato de se ter a sua modelagem já testada, por meio de simulações de alguns acidentes descritos em seu respectivo FSAR (Final Safety Analysis Report), com o RELAP5. O trabalho compara os resultados das simulações com condições diferentes a respeito das medidas mitigatórias do SAMG a fim de avaliar a eficácia de cada uma dessas medidas.

    Palavras-Chave: reactor accidents; angra-2 reactor; pwr type reactors; safety analysis; computer codes; loss of coolant; atmospheres; ambient temperature

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  • IPEN-DOC 24920

    MENZEL, SILVIO C. . Estudo de alternativas de alimentação elétrica. Projeto Orquídea – Agregado ao Loop 70 – Galpão de Experimentos. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Agosto, 2018. (IPEN-CEN-PSE-RMB-007-00-RELT-008-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: É apresentado um estudo de alternativas de alimentação elétrica para atender as cargas elétricas do Projeto Orquídea a ser implantado nas instalações do experimento Loop 70 do Galpão de Experimentos do CEN, dentro da área do IPEN, Avenida Lineu Prestes, 2242, Cidade Universitária, São Paulo, SP.

    Palavras-Chave: rmb reactor; power supplies; fuel elements; hydrodynamics; energy; electrical equipment; nuclear facilities; ipen-mb-1 reactor

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  • IPEN-DOC 24919

    FREITAS, ROBERTO L. . Circuito Experimental Orquídea para testes de elementos combustíveis. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Setembro, 2018. (IPEN-CEN-PSE-RMB-007-00-RELT-007-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: Este relatório tem como objetivo apresentar o projeto de concepção do circuito experimental ORQUÍDEA para testes de elementos combustíveis, a ser construído no IPEN/CNEN. O projeto tem como principal característica a utilização de equipamentos e componentes do Circuito Experimental de Água - LOOP 70 visando diminuir os custos e o tempo de construção. Nele, são descritas as funções do circuito, as principais características de operação do circuito experimental ORQUÍDEA e dos seus equipamentos.

    Palavras-Chave: rmb reactor; stainless steels; fuel elements; reactors; iear-1 reactor; coolant loops; experiment results

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  • IPEN-DOC 24929

    BASSI, ROSANE; MYAKAWA, WALTER; NAVARRO, RICARDO S.; BAPTISTA, ALESSANDRA; RIBEIRO, MARTHA S. ; NUNEZ, SILVIA C.. Photodynamic Therapy to destroy pneumonia associated microorganisms using external irradiation source. In: DAI, TIANHONG (Ed.) LIGHT-BASED DIAGNOSIS AND TREATMENT OF INFECTIOUS DISEASES, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 1047917-1 - 1047917-5. (SPIE Proceedings Series, 10479). DOI: 10.1117/12.2290764

    Abstract: An endotracheal tube (ETT) is required for the management of critically ill, mechanically ventilated patients. Ventilatorassociated pneumonia (VAP) affects patients hospitalized in intensive care units; its risk of occurrence is 1% to up 3% for each day of mechanical ventilation. The polymicrobial nature of VAP is established with mixed bacterial-fungal biofilms colonizing the ETT. The microbial interaction enhances the microbial pathogenesis contributing to high indexes of morbidity/mortality. Antimicrobial Photodynamic Therapy (aPDT) could be a suitable therapy for decontamination of oral cavity and ETT at the same time, but the use of a fiber optics inside the ETT seems to not be appropriated since a cannula for secretion aspiration has to be introduced into the ETT to keep it´s lumen. The aim of this study is to proof the concept that an external light source from a LED is capable of reach all areas of the ETT. We use a commercial ETT, 60μM methylene blue (MB), and a 660nm diode laser and calculated the transmission coefficient of light in different situations as only tube, tube with biofilm and biofilm+MB. The results prove that is possible to transmit light through the tube even in the presence of MB and biofilm although a high attenuation of about 60% was measured depending on the tested condition.

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  • IPEN-DOC 24918

    SANTOS, SAMUEL C. ; SANTOS, SERGIO O. dos ; TORRES, WALMIR M. . Avaliação técnica amostral da instrumentação do LOOP 70 para utilização no Circuito Orquídea. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Março, 2018. (IPEN-CEN-PSE-RMB-007-00-RELT-004-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: Este relatório apresenta o resultado da avaliação técnica de uma amostragem de transmissores de pressão, transmissores de pressão diferencial e transmissores temperatura do LOOP 70 para verificação da viabilidade de utilização destes instrumentos no circuito experimental Orquídea.

    Palavras-Chave: rmb reactor; temperature dependence; coolant loops; pressure dependence; pressure range; experiment planning; accuracy; equipment

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  • IPEN-DOC 24928

    BARROS, JANAINA A.G. ; MAZIERO, JOANA S. ; MAMEDE, FERNANDA C.S. ; CAVALCANTE, ADRIANA K. ; ROGERO, SIZUE O. ; BATISTA, JORGE G.S. ; VARCA, GUSTAVO H.C. ; ROGERO, JOSE R. ; LUGAO, ADEMAR B. . In vitro and in vivo toxicity evaluation of resveratrol assisted gold nanoparticles. In: CONGRESSO DA SOCIEDADE LATINO AMERICANA DE BIOMATERIAIS, ORGAOS ARTIFICIAIS E ENGENHARIA DE TECIDOS, 14.; EDICAO DO WORKSHOP DE BIOMATERIAIS, ENGENHARIA DE TECIDOS E ORGAOS ARTIFICIAIS, 5., 20-24 de agosto, 2017, Maresias, SP. Anais... 2017. p. 926-933.

    Abstract: Gold nanoparticles (AuNP) are being investigated for diagnostic and therapeutic nanomedicines considering their low toxicity and stability against oxidation, among other features. The increasing production and use of AuNP can result in release of them into aquatic environment and the impacts on the aquatic organisms are not clear and the safety of AuNPs are still under investigation. This work aimed analyze the toxicity of resveratrol assisted AuNP synthesized in buffer phosphate pH 7.0 with approximately 47 nm in DLS and 15 nm in TEM analysis and gold ionic solution (Au+3). Cytotoxicity by neutral red uptake method and acute ecotoxicological assay on Daphnia similis were used. AuNP presented no cytotoxicity up to 246 mg L-1 while Au+3 showed IC50=7.95 mg L-1. AuNP CE50 was 113.15 mg L-1 and for Au+3 0.05 mg L-1. More studies can be conducted for the determination of safety ionic Au+3 and AuNP concentrations in aquatic environment.

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  • IPEN-DOC 24917

    TORRES, WALMIR M. . Memorial de cálculo do Circuito Hidrodinâmico para Testes de Elementos Combustíveis (Orquídea). São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Março, 2018. (IPEN-CEN-PSE-RMB-007-00-RELT-003-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: Este relatório apresenta o memorial de cálculo do circuito Orquídea, que é o circuito experimental que está sendo projetado para a realização de testes hidrodinâmicos em elementos combustíveis (ECs) com placas planas paralelas do tipo MTR, para reatores nucleares de pesquisa, e que deverá ser construído no IPEN. Esse circuito experimental será utilizado para a realização dos testes necessários para a qualificação dos elementos combustíveis do reator RMB. O dimensionamento do circuito considera as condições mais críticas de operação, ou seja, as condições necessárias para atingir a velocidade de escoamento crítica em um EC tipo MTR, com escoamento ascendente, como o do reator RMB.

    Palavras-Chave: fuel elements; fuel plates; hydrodynamic model; calculation methods; mathematical solutions; reactors; pressure drop; rmb reactor; tubes

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  • IPEN-DOC 24916

    FAINER, GERSON ; FALOPPA, ALTAIR A. ; ALMEIDA, JOEDSON T. de . Circuito Orquídea: avaliação estrutural do pressurizador V-102. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Julho, 2018. (IPEN-CEN-PSE-RMB-007-00-RELT-006-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: O objetivo deste relatório técnico é documentar a avaliação mecânica do: “ Pressurizador V-102” do Circuito Experimental de Água (“CEA”) do IPEN, também conhecido como “Loop 70”, para se verificar a possibilidade de sua reutilização no Circuito Hidrodinâmico para testes de Elementos Combustíveis – Orquídea. O projeto e construção do Pressurizador V-102 foi desenvolvido com o código ASME VIII division 1 no ano de 1977. O Pressurizador V-102 foi avaliado, através da análise estrutural das partes mecânicas, aplicando o código do projeto original, ou seja, ASME VIII division 1 nas seguintes condições:  Pressão interna = 2.0 N/mm2;  Temperatura de Operação = 60º C. Os resultados da avaliação podem ser resumidos conforme descrito abaixo:  Espessura de parede das partes mecânicas pressurizadas atendem os requisitos de espessura mínima;  A máxima pressão de trabalho (MAWP) é 5.8 N/mm2;  Os bocais não requerem reforço; Os bocais: N1, instalado em um flange cego, e N4, prolongado para o interior do vaso V-102 são configurações estruturais não previstas pelo código ASME VIII, Division 1  A distância entre bocais atende o critério da distância mínima;  As tensões nos flanges, de ½”, ¾”, 1½” e 10”, atendem os limites admissíveis; O flange cego aparafusado de 10” e com um bocal instalado é uma configuração estrutural não prevista pelo código ASME VIII, Division 1  As tensões nas soldas de topo e filete atendem os limites admissíveis;  Não foi encontrada nenhuma referência, relatório ou documento, que relate alguma inspeção em serviço realizada nas partes mecânicas do Pressurizador V-102. A avaliação estrutural do flange cego e bocais N1 & N4 foi desenvolvida, adotando-se a metodologia do código ASME VIII division 2. Foi, então, realizada a análise de tensões do Pressurizador V-102, aplicando-se o método das tensões elásticas, com o programa de análise estrutural por elementos finitos ANSYS. As tensões equivalentes calculadas para o flange cego e bocais N1 & N4, na condição de projeto e operação, atendem os limites prescritos pelo código ASME VIII division 2. Deste modo, está comprovada a adequação mecânica e estrutural das partes mecânicas do Pressurizador V-102. Considerando que não há registros de inspeções periódicas do Pressurizador V-102, desde o início de sua operação em 1977, recomendamos, antes da sua reutilização no circuito “Orquídea”, o seguinte procedimento:  “Inspeção Visual interna e externa das partes mecânicas do Pressurizador V-102”.

    Palavras-Chave: pressurizers; fuel elements; hydrodynamics

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  • IPEN-DOC 24915

    FAINER, GERSON ; FALOPPA, ALTAIR A. ; ALMEIDA, JOEDSON T. de . Circuito Orquídea: avaliação estrutural do tanque de armazenamento / desaerador V-101. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Janeiro, 2018. (IPEN-CEN-PSE-RMB-007-00-RELT-005-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: O objetivo deste relatório técnico é documentar a avaliação mecânica do:  Tanque de Armazenamento / Desaerador (V-101) do Circuito Experimental de Água (“CEA”) do IPEN, também conhecido como “Loop 70”, para se verificar a possibilidade de sua reutilização no Circuito Hidrodinâmico para testes de Elementos Combustíveis – Orquídea. O projeto e construção do Tanque V-101 foi desenvolvido com o código ASME VIII division 1 no ano de 1977. O Tanque V-101 foi avaliado, através da análise estrutural das partes mecânicas internas e externas, aplicando o código do projeto original, ou seja, ASME VIII division 1. Os resultados da avaliação podem ser resumidos conforme descrito abaixo:  Espessura de parede das partes mecânicas pressurizadas atendem os requisitos de espessura mínima;  A máxima pressão de trabalho (“MAWP”) é 1.15 N/mm2;  Os bocais não requerem reforço;  A distância entre os bocais N5 e N10 é menor que a distância mínima, portanto, uma análise de tensões, aplicando-se o método dos elementos finitos com o programa ANSYS, desta região do casco cilíndrico próxima aos bocais foi realizada, observando os requisitos do código ASME VIII division 2. As tensões calculadas no casco cilíndrico e bocais N5 e N10 atendem os limites prescritos pelo código ASME VIII, Division 1&2, na condição de projeto e operação;  As tensões nos flanges e parafusos atendem os limites admissíveis;  As tensões nas soldas de topo e filete atendem os limites admissíveis;  As tensões no perfil L das colunas atendem os limites admissíveis;  As placas de ancoragem foram calculadas aplicando-se o método dos elementos finitos com o programa ANSYS, e as tensões resultantes atendem os limites admissíveis;  Não foi encontrado nenhuma referência, relatório ou documento, que relate alguma inspeção em serviço realizada nas partes mecânicas do Tanque V-101. Portanto, está comprovada a adequação mecânica e estrutural das partes mecânicas do Tanque V-101. Considerando que não há registros de inspeções periódicas do Tanque V-101, desde o início de sua operação em 1977, recomendamos, antes da sua reutilização no circuito “Orquídea”, o seguinte procedimento:  “Inspeção Visual interna e externa das partes mecânicas do Tanque V-101”.

    Palavras-Chave: storage; tanks; deaerators; hydrodynamics; welding; fuel elements; flanges; mechanical efficiency; evaluation

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  • IPEN-DOC 24914

    MOLNARY, LESLIE de ; RIBEIRO, MARIA A.M. . Dados meteorológicos do sitio do RMB para uso no projeto detalhado. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Julho, 2018. (IPEN-CEN-PSE-RMB-006-00-INFT-001-01). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: Este documento tem como objetivo especificar e apresentar os dados relativos às variáveis meteorológicas obtidas nas torres meteorológicas do RMB-REATOR MULTIPROPÓSICO BRASILEIRO e do CEA - CENTRO EXPERIMENTAL DE ARAMAR, durante o período de 2007-2016. Também são apresentadas as variáveis meteorológicas obtidas pela torre meteorológica do CEA durante o período de 2002 e 2012. Esta informação consolida os valores das variáveis meteorológicas a serem utilizadas por todas as especialidades do projeto detalhado do Reator Multipropósito Brasileiro.

    Palavras-Chave: rmb reactor; meteorology; atmospheric pressure; climates; ambient temperature; humidity control

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  • IPEN-DOC 24926

    AZEVEDO, LUCIANA C. de; SA, ALESSANDRA S.C. de; ROVANI, SUZIMARA ; FUNGARO, DENISE A. . Propriedades do amido e suas aplicações em biopolímeros. Cadernos de Prospecção, v. 11, n. Edição Especial, p. 351-358, 2018. DOI: 10.9771/cp.v11i2.23173

    Abstract: O uso de amido pelos seres humanos remonta ao Egito antigo, onde papiros datados de 4000 a.c. eram elaborados com amido de trigo. Este carboidrato polimérico é constituído por unidades de glicose que se ligam formando estruturas de amilose e amilopectina, cuja proporção de cada uma dessas frações irá conferir características específicas, atribuindo diferentes aplicações comerciais a esta substancia. Muitos estudos estão sendo conduzidos para encontrar aplicações nobres para o amido, como por exemplo, o melhoramento das propriedades de materiais pela incorporação deste carboidrato como substrato polimérico, especialmente com o intuito de serem empregados em substituição ao plástico. Em relação a isso, pesquisas têm sido realizadas envolvendo a combinação com outros hidrocolóides, adição de novos plastificantes, nanocompósitos e polímeros inorgânicos na obtenção da solução filmogênica com o amido, assim como estão sendo desenvolvidas novas tecnologias de extrusão e secagem dos filmes, incluindo aplicação de radiação gama. O objetivo desta revisão foi apresentar as principais características e o avanço no uso de amido como polímero em filmes biodegradáveis e o interesse da comunidade científica e industrial por essa tecnologia. A prospecção revelou que, além de estar em ascensão desde 1990, a tecnologia de obtenção de biopolimeros está sendo intensivamente aprimorada por países como a China e EUA.

    Palavras-Chave: starch; polymers; inorganic polymers; polysaccharides; plasticity; biodegradation; biotechnology

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  • IPEN-DOC 24925

    BARBOSA, N.K.O. ; CARVALHO, V.S. ; ROSTELATO, M.E.C.M. ; VICENTE, R. ; SOUZA, D.C.B. . Caracterização de rejeitos radioativos sólidos na produção de sementes de iodo-125 para braquiterapia. In: ENCONTRO DE INICIACAO CIENTIFICA, 14., 25 de novembro, 2017, São Paulo, SP. Resumo... São Paulo: Universidade Nove de Julho, 2017. p. 45-45.

    Abstract: A braquiterapia é uma modalidade de radioterapia na qual uma fonte radioativa selada é colocada dentro ou próximo do órgão a ser tratado. As fontes de Iodo-125 são envidas por uma cápsula constituída de titânio. No Brasil, são importadas a um custo elevado sendo preciso cerca de 80 a 120 unidades para fazer cada tratamento. A produção destas fontes têm sido realizada, a nível de pesquisa, no Laboratório de Produção de Fontes para Radioterapia (LPFRT) localizado no Instituto de Pesquisas Energéticas e Nucleares (IPEN), com a intenção de nacionalizar a produção e diminuir os custos. As sementes são produzidas dentro de três células de produção, e rejeitos radioativos serão gerados nessas células. Desenvolver uma metodologia para caracterizar os rejeitos radioativos sólidos gerados durante a produção de sementes de Iodo-125 para tratamento de braquiterapia no LPFRT. A metodologia consistiu na realização de cálculos específicos para estimativa de volume e massa de cada rejeito sólido gerado nas células de produção. Sendo possível estimar, por semana, quanto de rejeito entrará no depósito, qual o espaço que ele ocupará e também seu peso. Para este cálculo, foi levado em consideração a geometria dos rejeitos. Além disso, foi feito cálculo de decaimento radioativo para definir o tempo que o rejeito ficará armazenado, para posterior descarte no sistema de coleta. Outro cálculo de decaimento radioativo foi feito para que se estime o valor de decaimento das atividades já armazenadas, usando o resultado da soma das atividades presentes no depósito. A taxa de entrada e saída do armazenamento foi estimado durante 1 ano, somando a atividade dos rejeitos que serão colocados semanalmente com a atividade já existente dentro do depósito. Assim, foi possível determinar o tempo necessário para armazenamento dos rejeitos em depósito intermediário, seguindo normas. Após esse processo, é possível notar que a taxa de volume, massa e radioatividade, diminui conforme maior tempo de retenção dos rejeitos por conta da dispensa dos materiais; e também, há o decaimento da radioatividade já presente no depósito. Os rejeitos radioativos sólidos serão liberados semanalmente com a taxa de radioatividade final de 9,60x105Bq. Cada lote poderá ser dispensado em lixo urbano a partir de 111 semanas de armazenamento, sem afetar o meio ambiente e a saúde de humanos e animais que porventura, entre em contato com os rejeitos sólidos.

    Palavras-Chave: brachytherapy; radioactive wastes; iodine 125; radiation sources

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  • IPEN-DOC 24913

    MOLNARY, LESLIE de ; RIBEIRO, MARIA A.M. . Dados meteorológicos do sitio do RMB para uso no projeto detalhado. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Julho, 2018. (IPEN-CEN-PSE-RMB-006-00-INFT-001-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: Este documento tem como objetivo especificar e apresentar os dados relativos às variáveis meteorológicas obtidas da torre meteorológica do CEA - CENTRO EXPERIMENTAL DE ARAMAR, durante o período de 2002 e 2012. Esta informação consolidará os valores das variáveis meteorológicas a serem utilizadas por todas as especialidades do projeto detalhado do Reator Multipropósito Brasileiro – RMB.

    Palavras-Chave: meteorology; ambient temperature; humidity control; climates; atmospheric precipitations; atmospheric pressure; bulbs

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  • IPEN-DOC 24935

    BORSOI, SAD S.; O. NETO, JESUS A.; PEREIRA, CARLOS E.M.; SARTORI, CARLOS A.F. . Low-voltage AC surge protective device assessment regarding nuclear plants. In: GLOBAL ELECTROMAGNETIC COMPATIBILITY CONFERENCE, 3rd, November 08-10, 2017, São Paulo, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2017. p. 1-5. DOI: 10.1109/gemccon.2017.8400665

    Abstract: This paper presents a methodology for low-voltage AC surge protective device (SPD) coordination. As motivation, the required nuclear plant reliability and safety criteria, in which the surge protection coordination can assume an important role, are emphasized. Due to the characteristics of the protection system, and the surge phenomena, an iterative methodology is applied. The SPD selection and specifications are based on the equipment immunity level, insulation and on SPD characteristics, like absorbed energy. Some results are presented and discussed, showing the suitability of the proposed methodology.

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  • IPEN-DOC 24927

    BADE, TAMIRIS G.; ROUDET, JAMES; GUICHON, JEAN-MICHEL; KUO-PENG, PATRICK; SARTORI, CARLOS . Experimental evaluation of voltage resonance on industrial cables. In: GLOBAL ELECTROMAGNETIC COMPATIBILITY CONFERENCE, 3rd, November 08-10, 2017, São Paulo, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2017. p. 1-5. DOI: 10.1109/gemccon.2017.8400663

    Abstract: This paper considers the resonance phenomena observed on cables connected to power converters, evaluating theoretically and experimentally the voltage amplification due to resonance on these cables. The experimental study was effectuated on cables typically used on industrial applications. Factors restricting resonance-due amplifications are considered, as well as the conditions under which resonance issues may rise in such systems.

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  • IPEN-DOC 24924

    ALMEIDA, JORGE V. de; SIQUEIRA, GLAUCIO L.; MOSSO, MARBEY M.; SARTORI, CARLOS A.F. . Effects on the antenna’s radiation pattern due to metamaterial-based sub-wavelength insulation. In: GLOBAL ELECTROMAGNETIC COMPATIBILITY CONFERENCE, 3rd, November 08-10, 2017, São Paulo, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2017. p. 1-5.

    Abstract: A metamaterial-based insulator is proposed for highly compact MIMO-systems. In previous work, the proposed insulator has been demonstrated to reduce efficiently the coupling at PEC boundaries between two very close antennas on a common ground plane. The present study concentrates on the effects of this insulator on the antenna radiation pattern. The chosen operating frequency is 2.4 GHz considering that it is a usual frequency for many indoor wireless applications. The theoretical results are supported by numerical simulations.

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  • IPEN-DOC 24912

    FALOPPA, ALTAIR A. ; OLIVEIRA, CARLOS A. de ; FAINER, GERSON . Avaliação estrutural dos tanques de água pesada do reator nuclear de pesquisa IPEN/MB-01. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Agosto, 2018. (IPEN-CEN-PSE-RMB-005-00-RELT-113-00). Restrito.

    Título do projeto: RMB

    Abstract: O objetivo deste relatório técnico é documentar a análise estrutural realizada para se verificar a integridade estrutural dos: “ Tanques Refletores de Água Pesada (D2O): Norte, Sul, Leste e Oeste” do Reator Nuclear de Pesquisa IPEN/MB-01. As análises estruturais dos Tanques Refletores de Água Pesada foram desenvolvidas, aplicando-se o código ASME VIII division 1 & 2, e os resultados estão resumidos na tabela abaixo:  ASME VIII division 1 – Tanques Refletores Norte & Sul & Leste & Oeste  Espessura das chapas atendem os requisitos de espessura mínima;  A máxima pressão de trabalho (MAWP) é 0.05 N/mm2;  A Pressão de Teste Hidrostático é 0.057 N/mm2;  Os bocais não requerem reforço;  A distância entre bocais atende ao critério da distância mínima. A distância entre bocais e borda da chapa dos Tanques Leste e Oeste atende ao critério da distância mínima. A distância entre bocais e borda da chapa dos Tanques Refletores de Água Pesada Norte e Sul é menor que a distância mínima;  As tensões calculadas por método analítico nas placas laterais, tampos e distanciadores dos Tanques Refletores de Água Pesada Leste e Oeste não atendem aos limites admissíveis. O método analítico não se mostra adequado para o cálculo completo dos Tanques Refletores de Água Pesada Norte e Sul. As questões acima não resolvidas serão tratadas pelo código ASME VIII division 2.  ASME VIII division 2 – Tanques Refletores Norte & Sul A integridade estrutural dos Tanques Refletores de Água Pesada Norte, Sul, Leste e Oeste foi verificada. Aplicou-se o método de análise das tensões elásticas para se obter as tensões equivalentes, calculadas de acordo com a teoria da energia de distorção máxima, através da simulação numérica com o programa de computador para análise estrutural por elementos finitos ANSYS, nas condições de Operação, Projeto e Teste Hidrostático. As tensões calculadas atendem aos limites prescritos pelo código ASME VIII division 2. Deste modo, os Tanques Refletores de Água Pesada (D2O) Norte, Sul, Leste e Oeste podem ser fabricados, e deverão operar nas seguintes condições:  “Pressão de Operação = 0.0326 N/mm2”;  “Máxima Pressão de Operação (MAWP) = 0.05 N/mm2”;  “Pressão de Teste Hidrostático = 0.057 N/mm2”.

    Palavras-Chave: ipen-mb-1 reactor; heavy water; tanks; neutron reflectors; reactors; aluminium; pressure vessels

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  • IPEN-DOC 24911

    YAMAGUCHI, MITSUO ; SANTOS, ADEMIR dos . Procedimento para análise de propagação das incertezas nas massas de combustível do reator IPEN/MB-01 tipo placa. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Julho, 2018. (IPEN-CEN-PSE-RMB-005-00-RELT-108-01). Restrito.

    Título do projeto: RMB

    Abstract: Este relatório apresenta um procedimento para analisar a propagação das incertezas nas massas do combustível do reator IPEN/MB-01 tipo placa.

    Palavras-Chave: fuel plates; uranium; ipen-mb-1 reactor; silicon; silicides; mass; uranium 238; uranium 236; uranium 235; uranium 234

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  • IPEN-DOC 24910

    YAMAGUCHI, MITSUO ; SANTOS, ADEMIR dos . Procedimento para análise de propagação das incertezas nas massas de combustível do reator IPEN/MB-01 tipo placa. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Junho, 2018. (IPEN-CEN-PSE-RMB-005-00-RELT-108-00). Restrito.

    Título do projeto: RMB

    Abstract: Este relatório apresenta um procedimento para analisar a propagação das incertezas nas massas do combustível do reator IPEN/MB-01 tipo placa.

    Palavras-Chave: storage; tanks; deaerators; hydrodynamics; welding; fuel elements; ipen-mb-1 reactor; mass; nuclear fuels; fuel plates; silicides; uranium silicides; uranium 238; uranium 236; uranium 235; uranium 234

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  • IPEN-DOC 24909

    FALOPPA, ALTAIR A. ; JUNQUEIRA, FERNANDO de C. ; OLIVEIRA, OTÁVIO L. DE . Procedimento para desmontagem e remontagem do núcleo do reator IPEN/MB-01. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEN, Março, 2018. (IPEN-CEN-PSE-RMB-005-00-RELT-104-00). Restrito.

    Título do projeto: RMB

    Abstract: Este documento tem como objetivo descrever as etapas de desmontagem do núcleo atual (combustível tipo varetas) e montagem do novo núcleo (combustível tipo placas) do Reator Nuclear IPEN/MB-01 incluindo a sequência, o descritivo e os requisitos para a execução do escopo.

    Palavras-Chave: ipen-mb-1 reactor; fuel rods; fuel plates; reactors; decommissioning; fuel assembly dismantling; fuel assemblies; switches

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  • IPEN-DOC 24880

    SANTOS, GUILHERME L.; FABRETTI, LEONARDO T.; DAGHASTANLI, NASSER A.; RIBEIRO, MARTHA S. ; PRATES, RENATO A.; KATO, ILKA T.. Interaction of methylene blue and fluconazole on photodynamic therapy. In: DEANA, ALESSANDRO M. (Ed.); PRATES, RENATO A. (Ed.); FERNANDES, KRISTIANNE P.S. (Ed.); DEANA, ALESSANDRO M. (Org.) FORUM INTERNACIONAL DE LASERTERAPIA, 3.; ENCONTRO DE ALUNOS E EX-ALUNOS DO PPG; BIOFOTONICA APLICADA AS CIENCIAS DA SAUDE, 05-06 de outubro, 2017, São Paulo, SP. Abstract... São Paulo: Universidade Nove de Julho, 2017. p. 76-76.

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  • IPEN-DOC 24879

    OLIVEIRA-SILVA, T.; LIMA-LEAL, C.R.; ALVARENGA, L.H.; SUZUKI, L.C. ; KATO, I.T.; RIBEIRO, M.S. ; PRATES, R.A.. Sensitization of glucose sensors as a pathway for increased uptake of methylene blue in Candida albicans with multidrug efflux systems. In: DEANA, ALESSANDRO M. (Ed.); PRATES, RENATO A. (Ed.); FERNANDES, KRISTIANNE P.S. (Ed.); DEANA, ALESSANDRO M. (Org.) FORUM INTERNACIONAL DE LASERTERAPIA, 3.; ENCONTRO DE ALUNOS E EX-ALUNOS DO PPG; BIOFOTONICA APLICADA AS CIENCIAS DA SAUDE, 05-06 de outubro, 2017, São Paulo, SP. Abstract... São Paulo: Universidade Nove de Julho, 2017. p. 72-72.

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  • IPEN-DOC 24878

    LIMA, LUANA S. de; NASCIMENTO, PALOMA A.; FERRETO, HELIO F.R. ; PARRA, DUCLERC F. ; LUGAO, ADEMAR B. . Estudo comparativo de dois métodos de análise de cristalinidade, raios-X e DSC, usando o Polietileno de Baixa Densidade (PEBD) injetado, irradiados por radiação gama / Comparative study of two methods of analysis crystallinity, X-ray and DSC, using a Low Density Polyethylene (LDPE) injected, irradiated by gamma radiation. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 3305-3309.

    Abstract: O polietileno de baixa densidade (PEBD) é um polímero de cadeias lineares com muitas e ramificações. O PEBD injetado foi irradiado por uma fonte de 60Co com 2000 kCi de atividade, na presença de ar, em doses de 5, 10, 20, 50 ou 100 kGy e taxas de dose de cerca de 5 kGy.h-1 em temperatura ambiente. Após a irradiação, foi necessário submeter às amostras a um tratamento térmico em uma estufa por 60 min a 100 ºC para a recombinação e aniquilação dos radicais residuais. As amostras injetadas e irradiadas foram caracterizadas para identificar os efeitos de degradação térmica, cisão e reticulação. Verificou-se uma degradação térmica da resina ao passar pelo processo de modelagem por injeção e irradiação. No processo de radiação tem-se alterações na cristalização e assim é possível comparar os métodos para obter-se a percentagem de cristalização do PEDB, por DSC e Raios X.

    Palavras-Chave: calorimetry; cobalt 60; comparative evaluations; crystallization; dose rates; gamma radiation; polyethylenes; radiation effects; x-ray diffraction

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  • IPEN-DOC 24877

    ROMANO, REBECA S.G. ; OLIANI, WASHINGTON L. ; PARRA, DUCLERC F. ; LUGAO, ADEMAR B. . Avaliação da degradação térmica do polipropileno irradiado / Evaluation of thermal degradation of irradiated polypropylene. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 2828-2832.

    Abstract: O polipropileno (PP) é um termoplástico semicristalino amplamente utilizado pelas suas excelentes propriedades. No entanto, sua produção em larga escala gera grandes quantidades de resíduos descartados no meio ambiente. Assim surgiu a necessidade de acelerar e controlar a sua degradação. O objetivo deste estudo é o controle da degradação do polipropileno irradiado com raios gama nas doses de 12,5 e 20 kGy comparando-os com o PP pristino sob condições de envelhecimento térmico. As amostras irradiadas foram expostas a envelhecimento térmico, com circulação de ar, durante 192 dias a 100°C e caracterizadas por Microscopia Eletrônica de Varredura (MEV), Análise Termogravimétrica (TGA), Calorimetria Exploratória Diferencial (DSC) e Ensaio Mecânico. A amostra de PP 20 kGy apresentou intensa oxidação com a presença de trincas superficiais e perda das propriedades mecânicas comparadas com o PP 12,5 kGy e com o PP pristino.

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  • IPEN-DOC 24876

    OLIANI, WASHINGTON L. ; PARRA, DUCLERC F. ; KOMATSU, LUIZ G.H. ; LINCOPAN, NILTON; RANGARI, VIJAYA K.; LUGAO, ADEMAR B. . Antibacterial effect of silver incorporated polyethylene blown film for active packaging use. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 2433-2437.

    Abstract: Food packaging is used to maintain the quality and safety of food products during storage and transportation, and to extend the shelf-life of food products. This is done by preventing unfavourable factors or conditions such as oxygen, light, moisture, spoilage microorganisms, chemical contaminants, mechanical resistance, etc. To be able to do so, packaging materials provide physical protection and also create the proper physicochemical conditions for each product necessary to obtain adequate shelf life and maintain food quality and safety. We report the preparation of polyethylene blown films containing silver nanoparticles by using the ultrasound technique. The silver nitrate was mixed with the surfactant oleic acid (AO) and sonicated for 30 minutes. This solution was mixed with polyethylene using a rotary mixer for 12 hours. Nanocomposites of low density polyethylene (LDPE) with linear low density polyethylene (LLDPE) blends and silver nanoparticles were prepared under melt in a twin screw extruder, using PE-g-MA as compatibilizer agent, ethylene graft maleic anhydride copolymer. The films were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX), field emission scanning electron microscopy (FESEM), differential scanning calorimetry (DSC), percentage reduction of colony-forming units (CFU). The bacterial effect of Escherichia coli and Staphylococcus aureus were assessed in detail.

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  • IPEN-DOC 24875

    KOMATSU, LUIZ G.H. ; OLIANI, WASHINGTON L. ; RODELLA, EVERTON F. ; PARRA, DUCLERC F. . Thermal-oxidation of HMSPP nanocomposites based on montmorillonite clay. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 2424-2427.

    Abstract: Nanocomposites based on high melt strength polypropylene (HMSPP) with montmorillonite clay were submitted to thermal assay. The samples were processed utilizing a twin screw extruder. The dumbbell samples were obtained by thermopressing and mounted in stove with air circulation. The effects of thermal assay on the nanocomposite were evaluated by Melt Flow Index (MFI), Energy Dispersive Scanning (EDS) and differential scanning calorimetry (DSC). It was observed that presence of clay can accelerate the process of thermal aging at lower content of 1wt%.

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  • IPEN-DOC 24874

    WIETKY JUNIOR, CLAUDIO; CORREA, ADRIANO M.; ANJOS, ERASMO A.; MAIA, ANDERSON; SILVA, LEONARDO G.A. ; ROSSINI, EDVALDO L.. Preparação e caracterização de nanocompósitos de PA 66/nanoargila / Preparation and characterization of PA 66/nanoclay nanocomposites. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 2405-2409.

    Abstract: Visando à eliminação da etapa de extrusão no processo de produção de nanocompósitos de poliamida 66/nanoargila montmorilonita preparou-se dois nanocompósitos, com diferentes porcentagens de compatibilizante (4 % e 0,24 %), por meio da técnica de intercalação por fusão. Os corpos de prova foram preparados por dois métodos diferentes: mistura mecânica em extrusora dupla rosca e injeção e, mistura manual e injeção. A avaliação da dispersão foi realizada por Microscopia Eletrônica de Varredura (MEV), a viscosidade pela medida do Índice de Fluidez (MFI) e as propriedades mecânicas por ensaios de tração e impacto Izod. A análise por MEV indicou que a nanoargila foi incorporada ao polímero de forma eficiente. O valor do MFI se manteve constante para o nanocompósito com mais compatibilizante e diminuiu cerca de 20% para o outro. Observou-se uma diminuição dos valores da tensão na ruptura da ordem de 10%, mas estes valores se mantiveram constante para os nanocompósitos preparados por ambos os métodos. Portanto, conclui-se que a incorporação da nanoargila, de forma geral, indicou perda das propriedades mecânicas, quando comparado à poliamida 66. No entanto, os valores similares, para ambos os métodos de preparação, sugerem a possibilidade de eliminação da etapa de extrusão.

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  • IPEN-DOC 24873

    OLIVEIRA, JOSE M.D.; COELHO, ANTONIO C.V.; BARBERATO, FERNANDA; HARADA, JULIO ; SILVA, LEONARDO G.A. ; CABRAL NETO, ABNER. Investigação das propriedades dos compósitos formados por resina uretânica elastomérica e vermiculita processada / Investigation of the properties of the composites formed by processed vermyculite and elastomeric urethane resin. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 2307-2310.

    Abstract: Na tentativa de melhorar a tensão de ruptura da resina uretânica elastomérica (TPU), foi estudada adição de vermiculita processada a esta resina. Os compósitos resultantes foram avaliados em microscopia eletrônica de varredura (MEV), Calorimetria Exploratória Diferencial (DSC), e análise termogravimétrica (TGA). Os resultados de tensão de ruptura obtidos para os compósitos formados pela resina uretânica elastomérica e vermiculita processada apontam para a necessidade estudos complementares de compatibilização e de processamento.

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  • IPEN-DOC 24872

    SEIXAS, MARCUS V. de S.; MOURA, ESPERIDIANA A.B. ; WIEBECK, HELIO. Processamento e caracterização de EVA com adição de celulose / Processing and characterization of EVA with cellulose addition. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 2234-2238.

    Abstract: O copolímero poli[(etileno)-co-(acetato de vinila)] (EVA) é utilizado principalmente com o objetivo de melhorar a resistência mecânica, a processabilidade, a resistência ao impacto e as propriedades de isolamento e transparência, sobretudo em embalagens coextrusadas para produtos alimentícios, filmes térmicos, embalagens para produtos refrigerados e congelados. O EVA reforçado com 1 % de celulose foi processado por extrusão, utilizando-se uma extrusora dupla-rosca. As amostras de EVA e do compósito EVA/Celulose foram caracterizadas por meio das análises de DSC, TG, MEV e ensaios de resistência à tração. Os resultados mostraram alterações significativas nas propriedades mecânicas e térmicas do EVA reforçado com celulose, quando comparadas às propriedades do EVA puro.

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  • IPEN-DOC 24871

    NAIME, NATALIA ; BRANT, ANTONIO J.C. ; LUGAO, ADEMAR B. ; PONCE, PATRICIA . Influência do tipo de tubetes de reflorestamento (biodegradáveis e de plástico) no desenvolvimento de mudas de Eucalyptus saligna / Influence of type of reforestation tubes (biodegradable and plastic) on development of Eucalyptus saligna seedlings. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 1573-1577.

    Abstract: Este trabalho teve como objetivo estudar a influência do tipo de tubetes de reflorestamento no desenvolvimento de mudas de Eucalyptus saligna, durante a fase de viveiro. Para tanto, foram analisados tubetes plásticos e biodegradáveis (sendo os primeiros obtidos do mercado brasileiro e os últimos fabricados pela empresa BIO&GREEN, a partir do bagaço de cana-de-açúcar) de diferentes volumes, comparando-os quanto (1) ao desenvolvimento das mudas de eucalipto e (2) às suas integridades físicas, até completarem 90 dias da semeadura. Os resultados mostraram que as mudas de eucalipto, em viveiro, se desenvolveram melhor nos recipientes de polietileno e indicaram que quanto maior o volume do tubete, melhor desenvolvida é a planta.

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  • IPEN-DOC 24870

    LINO, JULIANA dos S. ; AQUINO, AFONSO R. de . Proposta de classificação de brownfields. OLAM - Ciência & Tecnologia, v. 1, n. 1-2, p. 1-23, 2017.

    Abstract: Brownfields são uma realidade nas metrópoles. Áreas que foram contaminadas por atividades industriais, depósito irregular de resíduos ou de substâncias tóxicas, apresentam dificuldade em acompanhar as mudanças de uso e ocupação do solo, comuns nas dinâmicas da sociedade. Os processos de desindustrialização nas metrópoles resultam na identificação de um número crescente de brownfields. Considerando que as formas de gerenciamento e refuncionalização são temas contemporâneos, que impactam diversas áreas, como meio ambiente, desenvolvimento urbano e saúde pública, foi proposta uma metodologia de classificação dos brownfields, analisando suas especificidades, pois as áreas apresentam variações entre si. Foram selecionados atributos, que descrevam a qualidade ambiental da área e, por meio destes, as áreas foram classificadas em seis grupos distintos. A classificação dos brownfields pode auxiliar a melhor compreensão acerca destas áreas, com suas particularidades bem descritas e pode ser uma importante ferramenta na tomada de decisão sobre empreendimentos e o planejamento urbano.

    Palavras-Chave: brownfield sites; land pollution control; classification; classified information; environmental policy; soils; land use; environment; contamination regulations

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  • IPEN-DOC 24869

    LINO, JULIANA dos S. ; AQUINO, AFONSO R. de . Brownfields in São Paulo City. In: WORLD CONGRESS ON NEW TECHNOLOGIES, 4th, August 19-21, 2018, Madrid, Spain. Proceedings... 2018. p. 182-1 - 182-8. DOI: 10.11159/icepr18.182

    Abstract: Brownfields are a reality in the metropolis. Areas that have been contaminated by industrial activities, irregular waste deposits or toxic substances, are difficult to follow the changes in land use and occupation, familiar in the dynamics of society. Understanding the relationship between population shifts and use e occupation of urban land can help policymakers and planners ensure that cities remain economically productive and environmentally sustainable. Brownfields revitalization is an issue that has an essential role in The Sustainable Development Goal, as goal Sustainable Cities, and Communities. In this research, five districts on São Paulo city were chosen to analyse the contaminated areas and identify the percentage of revitalization e clean-up also considering the price of urban land and the number of the population residing in these districts. The results indicated that the process of revitalization and clean-up of contaminated land is happening in all five districts evaluated, in Santo Amaro the process is more evident. It is the same place where the price of the square meter is the most expensive and had the highest percentage of contaminated areas with confirmed risk. However, this revitalization process is different, given the essential factors of each district, as localization and zoning law. This difference means different answers on general public strategies to the revitalization of brownfields. So local studies can offer more instruments to policymakers.

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  • IPEN-DOC 24868

    ENGERROFF, JULIANO A.B.; KELLER, FREDERICO O.; LOPES, LEONARDO U. ; MASCHERONI, ARTHUR A.; TAKIISHI, HIDETOSHI ; WENDHAUSEN, PAULO A.P.. d-HDDR processing of Nd-Fe-B based alloys to obtain highly anisotropic nanocrystalline powders. Materials Science Forum, v. 899, p. 563-566, 2017. DOI: 10.4028/www.scientific.net/MSF.899.563

    Abstract: The HDDR (hydrogenation-disproportionation-desorption-recombination) process is an established powder metallurgy route to obtain Nd–Fe–B nanocrystalline powders for bonded magnets manufacturing. Therefore, both conventional (c-HDDR) and dynamic HDDR (d-HDDR) processes has been investigated to obtain Nd-Fe-B-based powders with different characteristics. Magnetic properties were measured by means of a hysteresisgraph and the powder obtained by d- HDDR showed strong anisotropy, allowing a Br of 1.1 T in the bonded magnet, whereas c-HDDR powder was isotropic with a Br of 0.6 T. Microstructural changes were characterized by X-ray diffraction (DRX) and scanning electron microscopy (SEM). X-ray patters of anisotropic powders made by d-HDDR showed high intensity reflection peaks indexed as (004), (105) and (006) planes in the aligning direction, due the texture inducement in c-axis of the main phase (Nd2Fe14B). However, SEM micrographs of c-HDDR powder showed a more homogeneous microstructure, with grain size of ~300 nm, when compared to d-HDDR powder that ranged from 300 nm to 500 nm. This difference is assumed to be the cause of lower intrinsic coercivity found in the c-HDDR powder.

    Palavras-Chave: hydrogenation; desorption; recombination; anisotropy; magnets; neodymium alloys; iron alloys; boron alloys

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  • IPEN-DOC 24867

    MENDES, MARCIO W.D. ; MENDES, NARAYANNA M.F. ; BRESSIANI, ANA H. de A. ; BRESSIANI, JOSE C. . Effect of NbH Particle size and cooling type on the microstructure, phase composition and microhardness of Ti-20Nb-20Zr alloy. Materials Science Forum, v. 899, p. 243-247, 2017. DOI: 10.4028/www.scientific.net/MSF.899.243

    Abstract: Titanium alloys are widely used as implants in orthopedics and dentistry due to their properties such as high strength, corrosion resistance, biocompatibility and good fatigue resistance. Alloys composed of non-toxic elements, like Nb and Zr, provide lowest Young’s modulus with values near to human bone modulus. The goal of this work was to study the effect of NbH particle size and cooling type on the microstructure, phase composition and microhardness of Ti-20Nb-20Zr alloy. The powders were produced by hydrogenation method. Two different powders of NbH were prepared: powders comminuted (C) and comminuted followed by milling (C+M). After, the alloy powders were milling and homogenizated for 6 h / 300 rpm and sintered at 1300 °C / 3h followed furnace cooling. Afterward, the specimens were treated at 1000 °C / 1 h and cooling in air and water. The samples were characterized by XRD, SEM and Vickers microhardness. The results showed that the alloy is classified as α + β. Vickers microhardness of Ti-20Nb-20Zr ranged between 680-700 and 540-600 HV from alloys prepared with NbH-comminuted and NbH comminuted + milled, respectively. Results indicated that NbH agglomerate behave as barriers for the sintering process of the alloy.

    Palavras-Chave: microstructure; titanium alloys; biological materials; metals; powders; powder metallurgy; niobium hydrides

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  • IPEN-DOC 24866

    MACHADO, GLAUSON A.F. ; ROCHA, ROSA M.; BRESSIANI, ANA H.A. . Composites obtained from alumina and polymer derived ceramic. Materials Science Forum, v. 912, p. 141-146, 2018. DOI: 10.4028/www.scientific.net/MSF.912.141

    Abstract: Alumina-mullite composites with low shrinkage can be made by reaction bond using mixtures of alumina, aluminum and silicon carbide. In this work, an alternative route is used to produce alumina composites with low shrinkage. Here alumina samples containing additions of 10 and 20 wt% of a preceramic polymer were warm-pressed and treated in the range of 900 -1500°C to produce alumina based composites. The obtained composites were analyzed by linear shrinkage and compared to pure alumina samples sintered at the same temperature range. It were also evaluated the density variation and crystalline phases formed during heat treatment of alumina composites. Results showed that alumina-silicon oxycarbide and alumina-mullite composites were obtained with lower shrinkage than pure alumina samples.

    Palavras-Chave: composite materials; silicon carbides; polymers; mullite; aluminium oxides; ceramics; pyrolysis

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  • IPEN-DOC 24865

    PIERETTI, EURICO F. ; PILLIS, MARINA F. . Electrochemical behavior of Nb2O5 films produced by magnetron sputtering. International Journal of Electrochemical Science, v. 13, n. 8, p. 8108-8115, 2018. DOI: 10.20964/2018.08.78

    Abstract: Metallic engineering materials generally form passive films on their surfaces and therefore are prone to localized corrosion, usually characterized by the occurrence of pits. The improvement of surface properties is a requirement for the metallic components used, for example, in petrochemical industry, in fuel cells, and in nuclear plants. The goal of this paper is to investigate the influence of Nb2O5 coatings on the electrochemical behavior of AISI 316 stainless steel. The films were deposited for 15, 30 and 50 minutes by using DC magnetron sputtering technique. The corrosion resistance was evaluated by monitoring the open circuit potential (OCP), the electrochemical impedance spectroscopy (EIS) and the linear potentiodynamic polarization (LP) in an aqueous 0.1 M H2SO4 electrolyte at 25 °C. Electrochemical tests revealed a more capacitive behavior of the Nb2O5-coated specimens when compared to the uncoated one. This fact indicates that the coated samples are less susceptible to corrosion. The deposited films show a protective character and can be used to avoid the degradation of the AISI 316 austenitic stainless steel in aggressive environments containing sulfur ions.

    Palavras-Chave: stainless steels; niobium oxides; coatings; surface coating; corrosion resistance; impedance; electrochemical corrosion; magnetrons; sputtering

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  • IPEN-DOC 24857

    SANTOS, JONNATAN J. ; LEAL, JESSICA ; DIAS, LUIS A.P. ; TOMA, SERGIO H.; CORIO, PAOLA; GENEZINI, FREDERICO A. ; KATTI, KATTESH V.; ARAKI, KOITI; LUGAO, ADEMAR B. . Bovine serum albumin conjugated gold-198 nanoparticles as model to evaluate the damage caused by ionizing radiation to biomolecules. ACS Applied Nano Materials, 2018. DOI: 10.1021/acsanm.8b01174

    Abstract: Gold nanoparticles (AuNPs) have several applications including in medicine. Considering cancer as one of the most common diseases for men and women, new treatments and more specific and effective drugs, which cause less side effects, have been actively pursued. Among them, gold-198 can be engineered as theranostic agents, working as contrast (exploiting gamma emission) and treatment agents (beta emission). Accordingly, a new procedure for the production of 14 nm diameter radioactive citrate protected gold-198 nanoparticles, that were then conjugated with bovine serum albumin utilizing 3-mercaptopropionic acid directly bound to AuNPs surface as anchoring groups, generating fully dispersible nanoparticles in aqueous media, are described. The effect of gamma and beta radiation on grafted BSA was evaluated by direct irradiation of the corresponding cold material and comparing with the damage caused on BSA grafted gold-198 nanoparticles prepared from a neutron activated gold foil. The investigation by fluorescence and Raman spectroscopy indicated that the damage to BSA chromophore groups is proportional to the dose (from 0.1 to 1 kGy) and that chromophores groups close to the particle surface are more prone to damage. Gold-198 nanoparticles conjugated with bovine serum albumin showed that process is much more localized next to nanoparticles surface since each gold core acts as a punctual radiation source. In short, AuNPs can enhance the damage caused by irradiation of cold nanoparticles and AuNPs@MPA-BSA is a suitable model to probe the effect of gamma and beta emitter on biomolecules. Furthermore, the strategy of diluting the gold-198 with cold gold atoms was shown to be suitable to control the activity of 198AuNPs aiming medical applications, since the damage to BSA was found to be proportional to the relative concentration of gold-198.

    Palavras-Chave: gold 198; cattle; blood serum; albumins; nanoparticles; ionizing radiations; therapy; gamma spectroscopy; neoplasms

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  • IPEN-DOC 24686

    LEVY, D.S. ; SORDI, G.M.A.A. . Web-based system for radiological protection programs: a repository for research, consultation and information. Brazilian Journal of Radiation Sciences, v. 03, n. 1A, p. 01-10, 2015. DOI: 10.15392/bjrs.v3i1A

    Abstract: In order to establish a Radiation Protection Plan or a Radiation Emergency Plan, Brazilian facilities should take into account all procedures based on national and international guidelines and recommendations. This information can be found in several documents published by different organizations over the past decades: the International Commission on Radiological Protection (ICRP), International Atomic Energy Agency (IAEA) and Comissão Nacional de Energia Nuclear (CNEN). Therefore, this project aims the informatization of the radiological protection programs in a single system in order to offer unified programs and inter-related information in Portuguese, providing Brazilian facilities a complete repository for research, consultation and information, combining computer technology and radiological protection in order to enhance the best benefits from information technology. This research work includes programs about: (1) Monitoring of Workplace (Monitoring for External Radiation, Monitoring for Surface Contamination, Monitoring for Air Contamination) and (2) Individual Monitoring (Monitoring of External Exposure and Monitoring of Internal Exposure, Monitoring for Skin and Clothing). WEB platform tools and functionalities were developed according to target public needs, regarding new possibilities of media, mobile access, and information sharing. The servers processing power added to the technology of relational databases allow to integrate information from different sources, enabling complex queries with reduced response time. Moreover, taking into account this is a pioneer project with the prospect of long-term use, the challenge involves the combination of multiple computer technologies that allows a robust, effective and flexible system, which can be easily adapted to future technological innovations.

    Palavras-Chave: alara; communications; iaea; icrp; indoor air contamination; information systems; monitoring; personnel; radiation protection; recommendations; surface contamination; brazilian cnen

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  • IPEN-DOC 24864

    STREFEZZA, CLAUDIA ; AMARAL, MARCELLO M.; QUINTO JUNIOR, JOSE ; GOUW-SOARES, SHEILA C.; ZAMATARO, CLAUDIA B. ; ZEZELL, DENISE M. . Effect of 830 nm diode laser irradiation of root canal on bond strength of metal and fiber post. Photomedicine and Laser Surgery, p. 1-6, 2018. DOI: 10.1089/pho.2017.4378

    Abstract: Objective and background: The correct selections of the cementing agent, the endodontic post material and placement protocol are critical to provide an increased longevity of the teeth that went through endodontic treatment. The irradiation with diode laser before post cementation, can promote an antimicrobial effect. However, there is a lack of information about the effect of 830 nm diode laser on the post bond strength. This study analyzed the effect of dentin root canal irradiation with high-intensity diode laser, at 830 nm, operating in continuous or pulsed mode, on the retention of metal or fiber posts, cemented with self-etching resinous composite (Panavia F) and zinc phosphate cement (ZnPO4). Materials and methods: Human roots were irradiated with diode laser (continuous and pulsed mode). The fiber posts were luted with Panavia F and the metal posts with Panavia F or ZnPO4 cement. Specimens were sectioned into three sections (cervical, middle, and apical). The bond strength was measured by a push-out mechanical analysis. For the statistical analysis, a three-way ANOVA test was applied following a Tukey's pairwise comparison with a significance level of p = 0.05. Results: The irradiated groups presented higher bond strength compared with nonirradiated group (p < 0.05), and the cervical and middle thirds presented higher on bond strength than the apical. The association of metal post and Panavia F presented higher bond strength when irradiated on continuous mode (p < 0.05). Fiber post and Panavia F presented higher bond strength associated to pulsed mode. The mode seems not to make a significant difference. Conclusions: These results corroborate the importance of the post bond to dentin and root canal debris removal to increase the tooth longevity. It was shown that the dentin to post bond strength were enhanced by the diode laser irradiation either on continuous or pulsed modes.

    Palavras-Chave: irradiation; lasers; cementing; dentistry; teeth; semiconductor diodes; antimicrobial agents

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  • IPEN-DOC 24863

    BERECZKI, ALLAN ; LOPEZ, MARCIO A.P.A. ; WETTER, NIKLAUS U. . Dynamically stable Nd:YAG resonators with beam quality beyond the birefringence limit and pumping of a singly resonant optical parametric oscillator. Optics Letters, v. 43, n. 4, p. 695-698, 2018. DOI: 10.1364/OL.43.000695

    Abstract: A simple, reliable, linearly polarized laser source with very high beam quality is demonstrated using standard diode-side-pumped Nd:YAG modules. The laser produced 30 W of output power with beam quality factor 𝑀2<1.15 over the entire range of input powers and beam quality of 1.02 at the laser operation point. This is, to our knowledge, the highest beam quality for a dynamically stable high-power laser that uses an optically isotropic crystal. The laser was used as a pump source for an optical parametric oscillator based on a periodically poled lithium niobate, producing wavelength in the 1.5–3.8 μm range.

    Palavras-Chave: lasers; resonators; diode-pumped solid state lasers; neodymium lasers; beams; quality factor; lithium; niobates; optical systems; parametric oscillators; optical equipment; laser pumping

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  • IPEN-DOC 24862

    GEONMONOND, RAFAEL S.; QUIROZ, JHON; ROCHA, GUILHERME F.S.R.; OROPEZA, FREDDY E.; RANGEL, CLARA J.; RODRIGUES, THENNER S. ; HOFMANN, JAN P.; HENSEN, EMIEL J.M.; ANDO, ROMULO A.; CAMARGO, PEDRO H.C.. Marrying SPR excitation and metal–support interactions: unravelling the contribution of active surface species in plasmonic catalysis. Nanoscale, v. 10, n. 18, p. 8560-8568, 2018. DOI: 10.1039/c8nr00934a

    Abstract: Plasmonic catalysis takes advantage of the surface plasmon resonance (SPR) excitation to drive or accelerate chemical transformations. In addition to the plasmonic component, the control over metal–support interactions in these catalysts is expected to strongly influence the performances. For example, CeO2 has been widely employed towards oxidation reactions due to its oxygen mobility and storage properties, which allow for the formation of Ce3+ sites and adsorbed oxygen species from metal–support interactions. It is anticipated that these species may be activated by the SPR excitation and contribute to the catalytic activity of the material. Thus, a clear understanding of the role played by the SPR-mediated activation of surface oxide species at the metal–support interface is needed in order to take advantage of this phenomenon. Herein, we describe and quantify the contribution from active surface oxide species at the metal–support interface (relative to O2 from air) to the activities in green SPR-mediated oxidation reactions. We employed CeO2 decorated with Au NPs (Au/CeO2) as a model plasmonic catalyst and the oxidation of p-aminothiophenol (PATP) and aniline as proof-of-concept transformations. We compared the results with SiO2 decorated with Au NPs (Au/SiO2), in which the formation of surface oxide species at the metal–support interface is not expected. We found that the SPR-mediated activation of surface oxide species at the metal–support interface in Au/CeO2 played a pivotal role in the detected activities, being even higher than the contribution coming from the activation of O2 from air.

    Palavras-Chave: catalysis; catalysts; plasmons; resonance; surfaces; oxidation; gold; nanostructures; spheres

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  • IPEN-DOC 24861

    RUBIO-MARCOS, FERNANDO; DEL CAMPO, ADOLFO; ROJAS-HERNANDEZ, ROCIO E.; RAMIREZ, MARIOLA O.; PARRA, RODRIGO; ICHIKAWA, RODRIGO U. ; RAMAJO, LEANDRO A.; BAUSA, LUISA E.; FERNANDEZ, JOSE F.. Experimental evidence of charged domain walls in lead-free ferroelectric ceramics: light-driven nanodomain switching. Nanoscale, v. 10, n. 2, p. 705-715, 2018. DOI: 10.1039/c7nr04304j

    Abstract: The control of ferroelectric domain walls at the nanometric level leads to novel interfacial properties and functionalities. In particular, the comprehension of charged domain walls, CDWs, lies at the frontier of future nanoelectronic research. Whereas many of the effects have been demonstrated for ideal archetypes, such as single crystals, and/or thin films, a similar control of CDWs on polycrystalline ferroelectrics has not been achieved. Here, we unambiguously show the presence of charged domain walls on a leadfree (K,Na)NbO3 polycrystalline system. The appearance of CDWs is observed in situ by confocal Raman microscopy and second harmonic generation microscopy. CDWs produce an internal strain gradient within each domain. Specifically, the anisotropic strain develops a crucial piece in the ferroelectric domain switching due to the coupling between the polarization of light and the ferroelectric polarization of the nanodomain in the (K,Na)NbO3 ceramic. This effect leads to the tuning of the ferroelectric domain switching by means of the light polarization angle. Our results will help to understand the relevance of charged domain walls on the ferroelectric domain switching process and may facilitate the development of domain wall nanoelectronics by remote light control utilizing polycrystalline ferroelectrics.

    Palavras-Chave: nanoelectronics; nanotechnology; ferroelectric materials; domain structure; raman spectroscopy; polycrystals

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  • IPEN-DOC 24860

    BATISTA, R.M. ; NARANJO, J.F.R.; MUCCILLO, E.N.S. . A versatile software for construction of the master sintering curve. Materials Science Forum, v. 912, p. 240-244, 2018. DOI: 10.4028/www.scientific.net/MSF.912.240

    Abstract: Several models have been developed over the last years to study the microstructure development of ceramic and metal powders during sintering. Among the most utilized methodology one may find the Arrhenius and the so-called Master Sintering Curve (MSC). Both models involve manipulation of a large number of data, and repetitive and time-consuming calculations. In this work, was developed a versatile and friendly-user software for a PC-type computer encompassing both methodologies. The software is flexible allowing for kinetic data evaluation such as the activation energy for sintering and sintering maps. Details of the software along with its application to investigate the sintering process of 10 mol% gadolinia-doped ceria are described.

    Palavras-Chave: sintering; computer codes; simulation; ceramics; gadolinium; cerium oxides; doped materials; fuel cells

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  • IPEN-DOC 24859

    ABREU, CAIO P. de ; COSTA, ISOLDA ; MELO, HERCILIO G. de; PEBERE, NADINE; TRIBOLLET, BERNARD; VIVIER, VINCENT. Multiscale electrochemical study of welded al alloys joined by friction stir welding. Journal of the Electrochemical Society, v. 164, n. 13, p. C735-C746, 2017. DOI: 10.1149/2.0391713jes

    Abstract: Friction stir welding (FSW) is an efficient way to join high strength aluminum alloys. However, FSW generates different microstructural areas in contact that may give rise to galvanic couplings, affecting the corrosion resistance of the assembly. In the present work, a multiscale electrochemical study of the 7475-T651 and 2024-T3 aluminum alloys butt-joined by FSW was carried out.Much lower impedances were associated with the FSW affected zones compared to the two aluminum base metals tested individually. Corrosion of the welded system resulted in the establishment of galvanic coupling, shown by local electrochemical impedance spectroscopy (LEIS) measurements, at which the AA7475 behaves anodically with respect to the AA2024. A Zn deposit was observed on the intermetallic particles of the AA2024 after 24 h of immersion in the electrolyte resulting from the galvanic coupling, which seems to reduce the galvanic coupling effects. Such a behavior in combination with LEIS results allowed a description of the galvanic coupling development between two different aluminum alloys (AA2024-T3 and AA7475-T761) butt-welded by FSW as a function of time from the early stage of immersion.

    Palavras-Chave: welding; microstructure; corrosion; corrosion resistance; aluminium alloys; electrochemistry; impedance; spectroscopy

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  • IPEN-DOC 24858

    BARBOSA, ANDREA Q.; SILVA, ROMULO A.S.; PIRES, MARIA A.F. ; LIMA, ALVARO S.; MADI, RUBENS R.; MARQUES, MARIA N.. Elaboration of the water safety plan in a water supply system in the brazilian northeast. International Journal of Development Research, v. 8, n. 2, p. 18810-18815, 2018.

    Abstract: The Water Safety Plan is a tool used to identify, assess and manage health risks related to any water supply system. In order to do so, a study was carried out in a supply system, located in the northeast of Brazil, composed by Fountain Caldas (P1) and Well Cipó (P2), as sources of raw water abstraction, and by the Distribution Reservoir (P3) treated. Water collection, land use and land use assessment and analysis of possible risks were carried out in the vicinity of these three points and in another site (P4) to obtain the treated water. The quality of the raw water was evaluated by the parameters of the Resolution of the Conselho Nacional do Meio Ambiente n° 396/2008 and the water treated according to the parameters of Ordinance nº 2914/2011 of the Ministry of Health. Observing the probability of occurrence of risk and the severity of consequence of the events. Therefore, 17 control points with low rating were detected, and two with moderate rating. Control measures were suggested for each identified critical point, mainly related to water quality monitoring and system maintenance.

    Palavras-Chave: water; water treatment; water quality; water supply; safety; planning; measuring methods; management

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  • IPEN-DOC 24856

    CORREA, EDUARDO L. ; BOSCH-SANTOS, BRIANNA ; FREITAS, RAFAEL S.; POTIENS, MARIA da P.A. ; SAIKI, MITIKO ; CARBONARI, ARTUR W. . Synthesis and atomic scale characterization of Er2O3 nanoparticles: enhancement of magnetic properties and changes in the local structure. Nanotechnology, v. 29, n. 20, 2018. DOI: 10.1088/1361-6528/aab3f8

    Abstract: In the investigation reported in this paper a modified thermal decomposition method was developed to produce very small Er2O3 nanoparticles (NPs). Particles structure, shape and size were characterized by x-ray diffraction and transmission electron microscopy which showed that the synthesis by thermal decomposition under O2 atmosphere produced very small and monodisperse NPs, allowing the investigation of finite-size and surface effects. Results of magnetization measurements showed that the smallest particles present the highest values of susceptibility that decrease as particle size increases. Specific heat measurements indicate that the sample with the smallest NPs (diameter ∼5 nm) has a Néel temperature of 0.54 K. The local structure of particles was investigated by measurements of hyperfine interactions with perturbed angular correlation spectroscopy using 111Cd as probe nuclei replacing the cationic sites. Results showed that the relative population of sites 8b increases in both the core and surface layer of particles.

    Palavras-Chave: nanoparticles; erbium oxides; spectroscopy; perturbed angular correlation; magnetization; synthesis; rare earths

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  • IPEN-DOC 24855

    PASCOAL, ERIC S.; KLEINGESINDS, EDUARDO K.; MOURA, ESPERIDIANA A.B. ; LUGAO, ADEMAR B. ; RODRIGUES, RITA C.L.B.. Corncob pretreated with the combination of electron beam irradiation and enzymes to enhance fermentable sugars for biofuel production. In: BRAZILIAN BIOENERGY SCIENCE AND TECHNOLOGY CONFERENCE, October 17-19, 2017, Campos do Jordão, SP. Abstract... São Paulo, SP: Sociedade Brasileira de Bioquímica e Biologia Molecular, 2017.

    Abstract: Lignocellulosic biomass pretreatment technologies have been taken up as a global challenge as it comprises to increase enzyme accessibility to biomass and yields of fermentable sugars. The reducing sugars released from pretreatment of the corn cob can be converted into biofuels. Corncob is a lignocellulosic material composed of cellulose, hemicellulose, and lignin. Cellulose and hemicellulose are polysaccharides constituted of simple sugars (hexoses and pentoses). However, these sugars are difficult to access, due to the presence of lignin, which is a polyphenolic molecule that provides a high recalcitrance to plant tissue. An appropriate biomass pretreatment disrupts the hydrogen bonds in crystalline cellulose, breaks down cross-linked matrix of hemicelluloses and lignin, and raises the porosity and surface area of cellulose for subsequent enzymatic hydrolysis. There are several pretreatment methods including, physical pretreatment (electron beam irradiation, grinding and milling, microwave, and extrusion), chemical pretreatment (alkali, acid, organosolv, ozonolysis, and ionic liquid), physico-chemical pretreatment (steam explosion, liquid hot water, ammonia fiber explosion, wet oxidation, and CO2 explosion), and biological pretreatment. This study evaluated electron beam irradiation (EB) in combination with enzymatic hydrolysis on corncob at different grain size to produce fermentable sugars. Dry biomass samples after characterization were exposed to EB radiation doses of 0, 30, 50, 70, 100, and 200 kGy. Enzymatic hydrolysis of the pretreated biomass samples were conducted using 10% of solid in Erlenmeyer flasks (125 mL) containing of 50 mL of medium prepared with sodium citrate buffer (50 mmol.L-1, pH 4.8), CellicCTec 2 25.50 FPU/g dry lignocellulosic material) and Tween 80 (9.8 % w/w) under 200 rpm at 50 °C. using the Cellic® CTec2 from Novozymes. The structural changes and degree of crystallinity of the pretreated biomass were studied by FTIR, DRX, DSC, TG and SEM analyses. Corncob in natura showed 6.3 % extractives, 40.3 % cellulose, 31.8 % hemicellulose, 17.3 % lignin, and 0.7 % ash. The highest conversion of cellulose to glucose (44.2%) was by using EB radiation doses of 200 kGy and reduced corn cob grain size. Significant improvement in the enzymatic saccharification (80.4%) of the EBI exposed biomass was observed compared to control. The sugars released can be converted to biofuel or another bioproduct. The EB in combination with enzymatic hydrolysis of corncob is an environmentally sound biomass pretreatment.

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  • IPEN-DOC 24854

    ANDRADE, C.G.; FIGUEIREDO, R.C.B.Q.; RIBEIRO, K.R.C.; SOUZA, L.I.O.; SARMENTO-NETO, J.F.; REBOUCAS, J.S.; SANTOS, B.S.; RIBEIRO, M.S. ; CARVALHO JUNIOR, L.B.; FONTES, A.. Photodynamic effect of zinc porphyrin on the promastigote and amastigote forms of Leishmania braziliensis. Photochemical & Photobiological Sciences, v. 17, n. 4, p. 482-490, 2018. DOI: 10.1039/c7pp00458c

    Abstract: Leishmaniasis is a neglected disease present in more than 88 countries. The currently adopted chemotherapy faces challenges related to side effects and the development of resistance. Photodynamic therapy (PDT) is emerging as a therapeutic modality for cutaneous leishmaniasis. Zn(II) meso-tetrakis(Nethylpyridinium- 2-yl)porphyrin (ZnTE-2-PyP4+, ZnP) is a cationic, water-soluble, zinc porphyrin-based photosensitizer whose photodynamic effect on Leishmania braziliensis was analyzed by evaluating the number of visibly undamaged and motile cells, cell membrane integrity, mitochondrial membrane potential, and ultrastructural damage. Treatment of parasites with ZnP and light induced damage in up to 90% of L. braziliensis promastigote cells. Propidium iodide labeling suggested the loss of plasma membrane integrity. In samples treated with ZnP and light, a hyperpolarization of the mitochondrial membrane potential was also observed. Ultrastructural evaluation of promastigotes after photodynamic treatment indicated a loss of cytoplasmic material and the presence of vacuoles. Scanning electron microscopy showed wrinkling of the plasma membrane and a reduced cell volume. Additionally, the number of amastigotes per macrophage was reduced by about 40% after photodynamic application. The treatment showed no considerable toxicity against mammalian cells. Therefore, the results indicated that PDT associated with ZnTE-2-PyP4+ represents a promising alternative to cutaneous leishmaniasis treatment.

    Palavras-Chave: protozoa; trypanosomiasis; parasites; antimitotic drugs; therapy; porphyrins; zinc; cytochemistry

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  • IPEN-DOC 24853

    MOSCA, RODRIGO C. ; SANTOS, SOFIA N. ; NOGUEIRA, GESSE E.C.; PEREIRA, DAISA L. ; COSTA, FRANCIELLI C.; ARANY, PRAVEEN; ZEITUNI, CARLOS A. . Efficacy of photobiomodulation therapy in mitigating skin radiation damage. Lasers in Surgery and Medicine, v. 50, 29, p. S15-S16, 2018. DOI: 10.1002/lsm.22799

    Abstract: Background: The use of sophisticated radiation dose delivery and fractionation has significantly improved cancer care. One of these involves localized, sustained ionizing dose delivery termed brachytherapy. Despite it therapeutic efficacy, specific side effects of brachytherapy include localized skin damage and breakdown for which only palliative treatments are currently available. The use of low dose biophotonics treatments to promote tissue healing is termed photobiomodulation (PBM) therapy. The aim of this study was to evaluate efficacy and molecular pathways of PBM therapy using two common wavelengths, red and near-infrared (NIR) to treat radiation wounds in athymic mice subjected to brachytherapy (sustained ionizing radiation from 125I seeds). Study Design/Materials and Method: A pilot study was performed with thirty-six athymic mice were accomplished for 60 days and divided into six groups: Surgical Control Group (No radiation and no PBM treatments); Radiation Control Group (125I seed 0.4252 mCi, no PBM); NIR-PBM Control Group (NIR PBM alone, LED at l¼880 nm); Red-PBM Control Group (Red PBM alone LED at l¼660 nm); Radiation- NIR PBM Group; Radiation-Red PBM Group. Following 21 days, radiation-induced wounds are evident. PBM treatments (both wavelengths with output power 40mW for 20 s, fluence 20 J/cm2 on top of implantation site) were performed every week up to 60 days. Wounds were evaluated every 7 days digital imaging, Laser Doppler Flowmetry (LDF) and tissue temperature with a thermographic camera. We also performed mPET-CT imaging using radioactive fluorodeoxyglucose (18F-FDG) at 51 and 81 days post-implantation. Animals were sacrifices progressively at each time point to correlate clinical observations with imaging and molecular tissue analyses. Tissues were collected to analyze molecular pathways correlating with inflammation, immune response, wound healing and angiogenesis using mRNA (qRT-PCR) and protein expression (immunostaining). Results: Both PBM treated groups demonstrated significant (p<0.05) improvements in skin radiation wound healing as compared to radiation group. Distinct improvements in clinical wound size and closure, improved tissue perfusion and reduced inflammation as evidenced by decreased wound thermal images. These wounds were also noted to have significant differences in the cytokine profiles (TGF-b, VEGF and PDGF) correlating with better healing responses. Radiation damage reduces brown fat composition that can potentially contribute to additional radiation-associated morbidities. The mPET-CT imaging noted significant preservation of brown fat composition in PBM-treated radiation alone groups. Further validation of these pathways is ongoing. Conclusion: Within the parameters of this study, PBM treatments demonstrated improved healing in radiation wounds due to ionizing radiation from 125I seeds. Ongoing work is examining the precise molecular pathways contributing to these therapeutic benefits. It is hoped this study will enable further development of this innovative therapy for managing side- effects from radiation treatments.

    Palavras-Chave: neoplasms; brachytherapy; radiation doses; radiation injuries; wounds; biological recovery

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  • IPEN-DOC 24852

    SOUSA, THAINA S. ; JACOVONE, RAYNARA M.S. ; SOARES, JAQUELINE J.S. ; RODRIGUES, DEBORA F.; SILVA, FLAVIA R. de O. ; GARCIA, RAFAEL H.L. ; ZAIM, MARCIO H.; SAKATA, SOLANGE K. . Antimicrobial activity of Graphene Oxide/Silver nanocomposite obtained by Electron Beam. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Graphene oxide is a carbon-based nano material that has a high specific surface area, high chemical stability, excellent electrical and thermal conductivities, high mechanical resistance, the oxygen groups facilitate dispersion in polar solvents and its functionalization. In the literature, is described several methods of metal incorporation on graphene oxide surface using toxic reagents or with long periods of reaction. The objective of this work is to develop an innovative and sustainable method of incorporating silver into graphene oxide that does not involve toxic reagents or generated residues. in a short reaction time at room temperature beyond the use of the as an alternative process to the chemical processes traditional.A silver solution in the complex form was added to a dispersed graphene oxide in water/isopropanol solution. The mixture wassubmitted to a dose of radiation ranged from 150 to 400 KGy using a electron beam acelerator. 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 antimicrobial activity of GO/Ag was observed by Escherichia coli, a Gram negative bacterium and Bacillus subtilis a Gram positive bacterium in solid culture medium. The minimum inhibitory concentration of GO/Ag was 50 mg/L. .It is noteworthy that the incorporation of silver occurred at the same time the reduction of graphene oxide without the generation of toxic chemical residues.

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  • IPEN-DOC 24851

    SOBRINHO, LUIZA F. ; GOTO, PAULA T. ; GARCIA, RAFAEL H.L. ; FRANCISCO, DANIEL; ANGNES, LUCIO; SAKATA, SOLANGE K. . The study of chemical and physical properties of Polyaniline-Graphene Oxide and Palladium Polyaniline-Graphene Oxide composites. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: A Polyaniline (PANI)-Graphene Oxide (GO) composite was studied for the electrical activities. The GO was obtained by modified Hummers method. For the palladium nanoparticles (Pd-NPs) incorporation, it was established an environmentally friendly approach based on electron beam reduction. The chemical characterization was performed by Fourier Transform Infrared (FTIR) spectroscopy, Thermogravimetry (TG), X-ray Diffraction (XRD) and for the electrical properties Cyclic Voltammetry (CV) in alkaline medium and conductivity measurements. The FTIR spectroscopy and TG were used to obtain the composition of the synthesized materials, while XRD pattern indicated polymerization quality and the crystallization degree of the samples. The CV and conductivity measurements indicated the electrical activity of the composite. The results showed the GO amount was directly proportional to the resistivity of PANI, and when the Pd (Pd-Pani-GO) was present, the CV showed a larger current than the Pd-GO. The high electrochemical performance of the Pani-GO electrode could be due the increasing active sites for the deposition of polyaniline provided by large surface areas of graphene oxide sheets and the synergistic effect between polyaniline and GO. These results demonstrated the importance and great potential of graphene oxide in the development of high-performance conductivity system based on polyaniline.

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  • IPEN-DOC 24850

    SOARES, JAQUELINE J.S. ; JACOVONE, RAYNARA M.S. ; MATHOR, MONICA B. ; ZAIM, MARCIO H.; MAIZATO, MARINA J.S.; CESTARI, IDAGENE A.; JATENE, FABIO B.; SAKATA, SOLANGE K. . The effect of GO-PEG-NH2 on the mechanical resistance of bovine pericardium used in cardiovascular device. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Valvular heart disease (VHD) is a clinical condition where one of the four-heart valves is damage or has a defect. It was estimated that approximately 300,000 to 400,000 heart valve replacement surgeries were performed in 2014. There are two types of prostheses, the bioprothesis and the mechanical prosthesis. Even though the first one presents a smaller rejection, its durability is reduced due to calcification followed by deterioration. The objective of this work was to increase the durability of prostheses made from bovine pericardium (BP) by incorporating GO functionalized with amino-PEG (GO-PEG-NH2). Briefly, GO functionalized was firstly sterilized with gamma radiation and then incorporated to BP in two different ways: chemical and physical. Mechanical characterization assays of BP treated with GO-PEG-NH2 and untreated (control) were performed in an INSTRON model 3365 universal test equipment using the BioPlus accessory, which allows the assays to be carried out immersed in a physiological solution of 0,9% NaCl at 36 °C, simulating the environment of material’s application. The static deformation in the uniaxial direction of the test specimens was verified using the ASTM D638-10 standard test method for tensile properties of plastics, 2010 from the American Society for Testing and Materials (ASTM Standards). The results indicated that GO-PEG-NH2 improved the mechanical strength of the biomaterial, increasing the resistance to permanent plastic deformation, maximum supported load, flow limit, maximum traction tension, rupture tenacity and rupture traction tension no matter of GO-PEG-NH2 incorporation methods and it is possible to improve the performance of bioprothesis by coating them with GO-PEG-NH2 and consequently increasing their durability.

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  • IPEN-DOC 24849

    SOARES, JAQUELINE J.S. ; COSTA, CARLOS A.R.; JACOVONE, RAYNARA M.S. ; ZAIM, MARCIO H.; SAKATA, SOLANGE K. . Characterization by atomic force microscope (AFM) of graphene oxide and graphene oxide-PEG-NH2 incorporated in bovine pericardium. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Atomic force microscopy (AFM) is a technique that allows images from the surface topography with high spatial resolution at Nano metric scales. AFM has being used in several fields in science such as Biology, Medicine, Chemistry and Pharmaceuticals. In this study, the tecnhique was used to characterize graphene oxide and graphene oxide functionalized with amino-PEG (GO-PEG-NH2) in the bovine pericardium (BP) surface. The treatment of BP with GO and (GO-PEG-NH2) improved the mechanical properties of the biomaterial that will be used in the manufacture of cardiovascular device that is used to replace heart valves. For the BP coating, two different pathways were tested: 1) chemical pathway using solution containing 1-Ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and GO; and 2) in physical adsorption the incorporation were performed by ultrassom. The same procedure was performed to incorporate GO-PEG-NH2. The images of the BP with its modified surface were obtained by AFM and proof the efficiency in the two incorporation processes. The study also demonstrated the applicability of AFM to characterize incorporated nanomaterial in the biological samples.

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  • IPEN-DOC 24848

    SEIXAS, MARCUS V. de S. ; RANGARI, VIJAYA K.; MOURA, ESPERIDIANA A.B. ; WIEBECK, HELIO. Preparation and characterization of nanocellulose from sugarcane bagasse. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Nanocellulose is steadily gaining attention since this material is a renewable alternative to reinforce polymers. Research and development of materials obtained from renewable natural sources have been the focus of attention in various engineering applications. The residues from different kinds of lignocellulosic materials has great potential for production of biocomposites, which are applied in optoelectronic devices, packaging, and building. The main object of this work was study of nanocellulose preparation from sugarcane bagasse and its characterization. The sugarcane bagasse was submitted to chemical treatment for separating of the cellulose from the lignocellulosic material, bleaching with hydrogen peroxide followed by sonication treatment for obtaining nanocellulose. Sonication treatment solution was prepared with a cellulosic material in water/DMF(dimethylformamide)/ethanol. Sonication treatment was done in a DES500 ultrasonic cell tip/horn sonicator with a 20 kHz ultrasonic frequency. The nanocellulose samples were characterized by FTIR, XRD, FE-SEM and TEM analysis. According to the results, the methodology used in this work presented a great potential to the obtaining of nanocellulose for applications in the development of new nanocomposite materials.

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  • IPEN-DOC 24847

    SANTOS, JONNATAN J. ; LEAL, JESSICA ; DIAS, LUIS A.P. ; TOMA, SERGIO H.; CORIO, PAOLA; ARAKI, KOITI; GENEZINI, FREDERICO A. ; KATTI, KATTESH V.; LUGAO, ADEMAR B. . Synthesis of high stable gold (198) nanoparticles for radiotherapy. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Cancer has become a problem in the last years, is expect be diagnosed more than 500 000 new cases in 2017, only in Brazil, according to Brazilian Cancer Nacional Institute. Among women breast cancer is the most common and among men the most representative is prostate cancer, and although treatments for both cancers have been already developed, new methods more efficient and that causes less damage to the patient are always being searched. Gold nanoparticles (AuNps) have many different applications on chemistry, biology, medicine, etc; their low reactivity and toxicity and high stability become it very interesting for bioapplications, such as drugs delivery and biosensing. In this work, we had developed a new method to prepare 198AuNps, from a leaf of gold bombed by neutrons, adapting Turkevich method, these nanoparticles were modified with bovine serum albumin (BSA) and characterized by multiple techniques, after 30 days (eleven half-life decays). This methodology was capable of generate AuNps with almost 14 nm and Zeta potential higher than -37 mV, very stable. BSA can be used for different applications, like a simple stabilizer or to increase cellular uptaking, but in our case its chromophore groups were utilized to follow damages caused by radiation, as a sensor for radiation damage, a dosimeter. Bellow are presented TEM image, Zeta potential measures and fluorescence spectroscopy of the 198AuNps-BSA samples.

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  • IPEN-DOC 24846

    SANTOS, MONIQUE C.L. ; OLIVEIRA NETO, ALMIR . Oxidation of methanol on PtRuIn/C in alkaline medium: effect of metals on the electrocatalytic activity. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: In this work the different electrocatalytic systems PtRu(50:50)/C, PtIn(50:50)/C, PtRuIn(50:10:40)/C and PtRuIn(50:40:10)/C were synthesized by the sodium borohydride reduction method, in order to be used as an anode in the alkaline fuel cell in the presence of methanol. The obtained materials were characterized by EDX, DRX and MET techniques. The reduction method applied in the synthesis was effective, since the particles showed good dispersion in the carbon support Vulcan XC72, according to the EDX and MET analyzes. The results obtained by XRD showed in all the diffractograms presented the FCC structure of platinum and a relative displacement of the equivalent peak to the plane (220) for values greater than and less than 2Ɵ. The mean crystallite size and the calculated net parameters indicated the insertion of Indium and Ruthenium atoms to the Platinum structure, assuming the formation of alloys. The electrochemical oxidation of methanol was studied by cyclic voltammetry, chronoamperometry and polarization curves. The PtRu(50:50)/C electrocatalyst in alkaline media showed the higher electrocatalytic activity fot the methanol electro-oxidation at room temperature compared to the others electrocatalysts prepared. The experiments in alkaline single direct methanol fuel cell (DMFC) also showed that PtRuIn(50:10:40)/C electrocatalyst exhibited higher performance for methanol oxidation at 80ºC, in comparison with the others electrocatalysts synthesized. These results indicated that the addition of Ru and In promote the methanol electrochemical oxidation, which could be attributed to the bifunctional mechanism (the presence of Ru and In oxides species) associated to the electronic effect (Pt-Ru-In alloys).

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  • IPEN-DOC 24845

    SANTANA, JULYANA G. ; SEIXAS, M.V. de S. ; ARANTES, MARIANA ; GUVEN, OLGUN; MOURA, ESPERIDIANA A.B. . Effects on Clay addition on properties of LDPE flexible films. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Studies have indicated that the addition of nanoparticles in flexible films improves performance flexible packaging, leading to better mechanical, thermal and barrier properties. Clay is an abundant mineral, inexpensive, easy to process, and provide considerable enhancements on the properties of polymers. Titanium dioxide (TiO 2 ) is widely used for its efficiency in scattering visible light, and imparting whiteness, brightness, and high opacity when incorporated into a plastic formulation. Low density polyethylene (LDPE) is generally used as a packaging material due to its good resistance, easy processing, low cost and high hardness. The objective of this study was to evaluate the effects of clay and TiO 2 nanoparticles addition on the properties of LDPE flexible films. LDPE with 1 wt % of TiO 2 addition and 1-3 wt. % of green Brazilian Clay, from Cubati, Pb, Brazil were prepared by melt extrusion process, using a twin-screw extruder Haake Rheomex P332 with 16 mm and L/D = 25, from Thermo Scientific. Then the LDPE/Clay nanocomposite was transformed into thin films using an extrusion blown film, single screw machine with 25 mm diameter and specimen test samples were obtained. The specimen samples were characterized by mechanical tests, UV-VIS, DSC, TG and FE-SEM analysis.

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  • IPEN-DOC 24844

    SAKATA, S.K. ; SOBRINHO, L.F. ; JACOVONE, R.M.S. ; SOARES, J.J.S. ; TOMINAGA, F.K. ; ANGNES, L.; GARCIA, R.H.L. . Sustainable synthesis of transition metals/graphene oxide nanocomposites by electron beam irradiation. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Graphene is nanomaterial with unique physical and chemical properties that makes it a precursor for the synthesis of new materials, such as conductive nanocomposites. Graphene can be obtained by the reduction of graphene oxide, but when it is incomplete, reduced graphene oxide (rGO) is produced with both graphene and graphene oxide properties: it is electrical and thermal conductor, it can be exfoliated in several polar solvents and moreover, the oxygen groups can later be functionalized, affording nanocomposites for electrochemical applications and also in biomaterials. A method of increasing the electrical conductivity of graphene-based compounds is by the incorporation of metallic nanoparticles. When these nanomaterials are joined together the surface area increases for the passage of electric current and the electrical conductivity. The chemical reduction method for the incorporation of metallic nanoparticle on GO involves toxic reagents or it is a time-consuming and it also requires high costs for the removal of excess reagents and by-products. The general synthesis of transition Metal/graphene-based nanocomposites by the electron beam in a sustainable process will be presented. The experiments were performed in a 1.5 MeV electron accelerator at room temperature and no hazardous wastes were generated. The nanocomposites were characterized by FT-IR, DRX and TEM/EDS as metallic nanoparticle at the average size of 5-20 nm incorporated into reduced graphene oxide layers. The electrochemical behavior of these nanocomposites was evaluated by cyclic voltammetry.

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  • IPEN-DOC 24843

    RODRIGUES, THENNER S. ; MOURA, ARTHUR B. ; SILVA, FELIPE A. e ; CANDIDO, EDUARDO G. ; BERGAMASCHI, VANDERLEI S. ; FERREIRA, JOAO C. ; LINARDI, MARCELO ; FONSECA, FABIO C. . Hardwired for success: Ni supported CeO2-Sm2O3 nanowires as a super stable catalyst for ethanol steam reforming. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: CeO2-based nanomaterials have been extensively employed in catalysis and industry, showing excellent performances towards a variety of applications. In the past few decades, great developments have been reported associating the properties of nanostructured CeO2 with its catalytic performances. Thus, an intense research in this field have been performed in order to increasingly improve the performances of these nanomaterials such as the precise control over their structures, morphologies, compositions, among others. We propose herein, the synthesis of a novel well-defined Sm2O3-doped CeO2 nanowires decorated with nickel nanoparticles as a novel catalyst with outstanding performance towards ethanol steam reforming (ESR). In order to address these challenges, we were inspired by a well-established hydrothermal method for the synthesis of CeO2 nanowires. Herein, through simple modifications in the original protocol allowed us the obtaining in high yield (97%) extremely well-defined CeO2-Sm2O3 nanowires exhibiting uniform distributions in lengths and diameters. XRD results (Figure 1A) suggested the introduction of Sm species into the CeO2 crystal lattices, in which the quantitative Sm3+(aq) conversion achieved 10 mol%, as corroborated by ICP-OES analysis. The resulting CeO2-Sm2O3 nanowires were then employed as support for the Ni incorporation (1 wt%) by a wet impregnation approach, and the obtained catalyst (Figure 1B) was evaluated towards the ESR displaying an exceptional stability even after 100 hours of process at 550 °C. More specifically, 100 % of ethanol conversion was observed with the formation of only H2 and CO2 (ESR products) and CO and CH4 as byproducts (both in low concentrations), indicating a good selectivity for ESR compared to the most recent literature. The characterization data for the Ni/CeO2-Sm2O3 nanowires after catalytic experiment (Figure 1C) indicated that, even after 100 hours at 550 °C, no loss of shape was observed as well as no carbon structures formation justifying the exceptional observed stability.

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  • IPEN-DOC 24842

    REIS, PEDRO R.S. ; SANTANA, JULYANA G. ; OLIVEIRA, RENE R. ; RANGARI, VIJAYA K.; MOURA, ESPERIDIANA A.B. . Biodegradable polymer blends reinforced with bio-hydroxyapatite nanoparticle - preparation and characterization. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Nowadays significant advances have been made in the development of biodegradable polymeric materials for biomedical applications. The purpose of this study was to preparation and characterization of biodegradable polymer blend reinforced with bio-hydroxyapatite nanoparticle from eggshell by sonochemical method. Biodegradable polymer blends based on PLA (Poly(lactic acid)) and the PBAT (butylene adipate-co-terepthalate)) reinforced with 1-5 wt. % of bio-hydroxyapatite were prepared by melt extrusion, using a twin screw extruder and injection molding machine to obtain specimen test. The effects of the bio-hydroxyapatite addition on properties of PLA/PBAT biodegradable blend were investigated by tensile tests, XRD, DSC, TG and SEM-FEG analysis and the correlation between the results was discussed.

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  • IPEN-DOC 24841

    PINHO, PRISCILA G.M. ; OLIVEIRA, FABIO B.V. ; ANDRADE, DELVONEI A. ; ROCHA, MARCELO S. . Experimental study of radiation influence on thermophysical properties of Al2O3 and ZrO2 nanofluids. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Nanofluids are a promising technology for application in nuclear reactor systems for high heat flux transport. As demonstrated by the recent researches, nanofluids have very interesting physical properties with respect to its ability to remove and transport of heat. There is, currently, research groups in the world conducting investigations on the influence of ionizing radiation on nanofluids and the possibility of its use as working fluid or cooling of the core of nuclear reactors core in cases of accidents. Among the countless applications presently proposed for the nanofluids, the applications in energy have special attention by academic and industrial interest. Studies demonstrate that nanofluids based on metal oxide nanoparticles have physical properties that characterize them as promising working fluids, mainly, in industrial systems in which high heat flux want to be removed. The nuclear reactors for power production are examples of industry where such an application has been proposed. However, there are no concrete results about the ionizing radiation effects on nanofluids properties. This work aims to present the initial results of the current study carried out with the objective to check the effects caused by that ionizing radiation on nanofluids based on Al2O3 and ZrO2 nanoparticles. Results from thermophysical analyses demonstrate that particular behavior on thermal conductivity, and density of such nanofluids can be observed as a function of temperature under no ionizing radiation effect. New investigations will analyze the application potentiality of some nanofluids in nuclear systems for heat transfer enhancement under ionizing radiation influence.

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  • IPEN-DOC 24840

    PERINI, ALINE A. ; FREITAS, ANDERSON Z. . Innovation trajectories: an IPEN´s nanotechnology competence roadmapping to match´s market mechanisms. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: The main objective of this work is to present general framework of the impact of technological innovation in the IPEN´s nanotechnology competence. The innovation are vital to improvement offer through chains front-to-end in health, environment, food and agriculture, energy, chemistry, education, entertainment and arts: treat supranational levels, offers accessible global technology. The pool innovation perspective in IPEN´s nanotechnology competence is a natural consequence of investments in Research and Development (R&D), between and among Universities and Public Research Institutions and multiple benefits arising from results, towards Awards in Science and policy disclosure. Geographically IPEN is held at São Paulo, Capital, one of the 10 biggest cities of the globe with high density on population and market demand. The innovation impact measures depend of (1) quality of diversified technology knowledge and (2) quality of diversified country industry knowledge that can be more specified. From this big view picture, the IPEN Technology Transference Office took account both dimensional innovation impact measures and listed detail in four (4) dimensional approach performance indicators over 5 years casting potential benefits outcomes in areas: a) human resource, b) services and products, c) research, teach and educational, d) intellectuals property, patents, projects, creativity and inventiveness. Regarding on Key Innovation Indicators and Policy of Impact Measures, the methodology applied to the present study consists oh the three main stages. First stage is a review with bibliometric analysis of market dynamics and technological management approach. The second stage was characterized by the data collection on management system from IPEN in labeled activities on nanotechnology. The third stage was marked to the understanding of the structure and the dynamics of nanotechnology markets, especially their sometimes acute response in innovation. The case study in IPEN´s in nanotechnology market built a preliminary assessment from a suitable a roadmapping system. Roodmapping is one of the most widely used tools as predictive exercise, supporting systematic planning and standardized strategy development. Many countries have developed standardization of roadmaps in various areas reported in intelligent systems, identifying significant opportunities and challenges associated with standardization in complex areas. IPEN´s nanotechnology competence in numbers is an inspirational approach engine and large influence in cultural and Institutional policymaking in Science, Technology and Innovation (S&T&I). The unique strengthen link can be matched from the S&T&I policy in term "technology transfer” in capacity building from push or/and pull innovation models. The central competence framework aimed at advancing knowledge necessary that would eventually lead to innovation trajectories and with strong security cultural insertion gauge to country succeed in international competition through innovation and growth, high-quality products and services, and research and education. Strategic differentiation could lead disruption in technology and development of new markets. The solutions by market-driven provide improvement at total quality managing front-to-end of technology transfer.

    Palavras-Chave: commercialization; technology assessment; technology impacts; research programs; nanotechnology; education; technology transfer; knowledge management

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  • IPEN-DOC 24839

    OSHIRO, MAURICIO T. ; SAKATA, SOLANGE K. ; POTIENS JUNIOR, ADEMAR J. . Adsorption isotherms for the removal of Am-241 in radioactive liquid wastes using magnetite nanoparticles. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Americium-241 (Am-241) is a radionuclide with half-life of 432 years, emitting alpha particles and low gamma energy and it is also considered radiotoxic. Am-241 is produced, in a low level, from nuclear fuel and laboratory wastes. Magnetite nanoparticles (Fe3O4) are iron oxides that possess highly magnetic properties, and its application for removal of water contaminants refers due to its high surface area which allows the adsorption capability and the facility to be prepared and removed from the aqueous medium. In This study, magnetite was synthesized by coprecipitation method largely described. Batch experiments were accomplished at room temperature, at pH 6 and the contacts varying from 2.5, 5, 10, 20, 30, 40, 50, 60 minutes and at 30 minutes for the isotherms experiments. The solid containing magnetite and Am-241 were removed with a magnet and the solution analyzed in a gamma-ray spectrometer (Canberra Model GX2518) which could be quantified. Results show that magnetite possess a capability of removal up to 80% of Am-241 at room temperature, indicating that magnetite nanoparticles are a good sorbent for the removal of radionuclides. Langmuir and Freundlich Isotherms models were investigated and the parameters obtained. Langmuir’s isotherm showed constants of KL (75.7575 L/mg), Q (0.1617 mg/g) and R2 (0.9892) and Freundlich’s isotherm exhibited values of KF (2.6416 [(mg/g).(L/mg)1/n]), 1/n (0.7853 mg/g) and R2 (0.8395), which indicates that the Am- 241 removal from magnetite fits more suitable the Langmuir isotherm model. The thermodynamics parameters, such as the enthalpy and entropy of adsorption, the activation energy, as well as, the kinetics studies are under development.

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  • IPEN-DOC 24838

    OLIVEIRA, FERNANDO M. ; POTIENS JUNIOR, ADEMAR J. ; FEJFAR, JOSE L.; RODRIGUES, DEBORA F.; DI VITTA, PATRICIA B.; SAKATA, SOLANGE K. . Immobilization of graphene oxide in a poly(divinylbenzene) matrix for the treatment of liquid radioactive waste containing 137Cs. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Cesium is one of the fission products of major radiological concern, it is often found in nuclear radioactive waste generated at nuclear power plants. Several methods are used to treat radioactive aqueous waste, especially adsorption, which is a technique that combines cost and efficiency and is widely used in preconcentration of radionuclides. Graphene Oxide (GO) has attracted great attention due to its functionalized surface, which includes hydroxyl, epoxy, carbonyl and carboxyl groups, with great capacity of complexation of metal ions and it can be used as adsorbent to remove cesium from radioactive liquid wastes.This work, GO was immobilized in poly(divinylbenzene) to increase the specific mass and grain size of the adsorbent, that can be easily remove from solution by vaccum filtration or being used in a fixed bed column. The incorporation of the GO on the polymer surface was confirmed by electron scanning electron microscopy (SEM) Figure 1.

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  • IPEN-DOC 24837

    OLIVEIRA, MARIA J.A. ; SANTOS, JONNATAN J. ; TOMA, SERGIO H.; ALCANTARA, MARA T.S. ; VASQUEZ, PABLO A.V. ; ARAKI, KOITI; LUGAO, ADEMAR B. . Hydrogels with silver nanoparticles for wound treatment. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: In recent years, the study and preparation of nanoparticles have attracted considerable interest for both fundamental and applied research. In biomedical area, silver nanoparticles have been a vast field of study, although antimicrobial properties have originated from their medical application since 19th century. Since silver has had several uses and its enormous potential for the treatment of injuries. Silver-containing topcoats are an excellent option for topical microbial combat on wounds that present infection, as well as being an essential tool for controlling bacterial load. Among these coatings are the hydrogel dressings with silver nanoparticles that have broad spectrum of antimicrobial action. In vitro studies have demonstrated bactericidal activity in strains of antibiotic resistant microorganisms. The objective of this work is characterize hydrogels with silver nanoparticles, prepared using polyvinylpyrrolidone (PVP), carboxymethylcellulose (CMC), used to treat wounds. A gamma radiation source cobalt-60 was used to crosslink the hydrogels, sterilize and form the silver nanoparticles simultaneously. Irradiation is recognized as a very viable tool because there is no need to add possibly harmful primers or crosslink that are difficult to remove. The results showed uniform distribution of the nanoparticles on the surface of the hydrogels, making it feasible for topical application.

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  • IPEN-DOC 24836

    MOURA, TIAGO S. ; GOTO, PAULA T. ; GARCIA, RAFAEL H.L. ; SALVADOR, PABLO A.V. ; SANTOS, PAULO S. ; SOARES, JAQUELINE J.S. ; NODA, LUCIA; SAKATA, SOLANGE K. . Gamma radiation assisted reduction of graphene oxide in unoxidized environment. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Graphene is a honeycomb like structure of carbon atoms of sp2 hybridization, with remarkable physical and chemical properties. Perhaps, the most desirable properties of a such material is the quasi-ballistic electronic transport and its excellent thermal conductivity that make graphene an excellent alternative to build electronic devices related to silicon, for instance. However, the lack of organic functions and the strong bonds between carbons in graphene nano-sheets make them unable to undergo functionalization reactions, that is important for many applications such as gas and biochemical sensors or nanoparticles decoration. So, in order to allow the functionalization of graphene nano-sheets and make possible a variety of new applications it was developed a nanomaterial based on the oxidation and exfoliation of graphite: the graphene oxide. This new material has epoxide and hydroxyl groups in the basal planes, with carboxyl groups in the borders, improving the hydrophilic properties and potential for chemical functionalization. Graphene oxide also serves as a starting material to graphene production by reduction routes. Partial reduction of graphene oxide leads to reduced graphene, a nanomaterial that combines both proprieties of graphene and graphene oxide: an excellent electrical and thermal conductivity, high superficial area and remaining oxygen groups that allow its functionalization. In the literature is described different ways to produce reduced oxide graphene from graphene oxide, such as chemical reduction using hydrazine hydrate or NaBH4, thermal reduction using high temperatures and plasma hydrogenation. Here in it is described a sustainable process to reduce graphene oxide in sodium bisulfite solution using gamma radiation. Exfoliated Graphene oxide (1-100mg/L) with NaHSO3 under inert medium was submitted to gamma radiation. The radiation dose ranged from 50 to 500 kGy and the product was centrifuged and analyzed by X-ray diffraction (XRD), Raman and infra-red (FT-IR) spectroscopies. It was observed that depending on the dose total or partial reduction was achieved. This methodology does not produce any toxic residue.

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  • IPEN-DOC 24835

    LUGAO, ADEMAR B. ; FAZOLIN, GABRIELA N. ; VARCA, GUSTAVO H.C. ; SANTOS, JORGE G. ; BARROS, JANAINA ; FUCASE, TAMARA ; SANTOS, JONNATAN J. ; LEAL, JESSICA ; GRASSELLI, MARIANO; KATTI, KATTESH V.. Radiation-induced "one pot" synthesis for cell therapies. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: The dream of Marie Curie lab’s expressed by Regaud and Lacassagne in 1927 was to administer radiations with penetration range of molecular dimensions to the organism and selectively fixed in the protoplasm of cells one seeks to destroy. Gold nanoparticles can be employed as a radiation sensitizer by utilizing mainly Auger effect and photoelectrons. Auger electrons are released in large numbers with low kinetic energy therefore these electrons damage cells over a very short range: less than the size of a single cell, on the order of nanometers. Gold-198 is a beta and gamma emitter can be employed for therapy as well as diagnostic. The radioactive properties of gold include: Au (βmax=0.96 MeV; t1/2 = 2.7 days) and Au (βmax =0.46 MeV; t1/2 = 3.14 days), making it a strong candidate for theranostics. However, Gold or Gold-198 need to internalize selectively in tumor cells. Conjugation with proteins and peptides can make them very selective. While radioactive nanoparticles can offer a much higher dose payload than ions for therapy and diagnostic, in addition to the huge surface to bind targeting species presented by the nanoparticles, functionalization with proteins may potentially increases the particle uptake by tumors or tissues. Albumin and Papain features a set of characteristics that assure applications as natural drug carriers with particular attractive properties in oncology. Albumin may be easily crosslinked and engineered towards loading of large number of hydrophobic molecules as well as hydrophilic ones. They can be bound in a reversible way and the delivery controlled by endogenous mechanism. Alternatively to conventional systems, albumin can be crosslinked by radiation in such way that dialdehydes or toxic chemicals are totally avoided . Conjugation of such materials with sugars, peptides, antibodies, proteins among others is routinely used nowadays for targeting. The main purpose of this work was the development of one pot in situ synthesis of radioactive gold 198 nanoparticle encapsulated by albumin for application in cancer Theranostics. While crosslinked albumin may provide a nontoxic coating on AuNPs with a controllable hydrodynamic diameter, conventional AuNP can be activated by nuclear reactor to produce AuNP. The gamma or beta radiation originated from the gold nanoparticle was used to crosslink the Albumin layer. The use of a radioactive particle able to emit radiation for crosslinking of the Albumin layer and simultaneous theranostic application was tried for the first time. The elegant procedure and simplicity of the production process combined with the properties of Au and the safety of AuNP/BSA make this new particle an exciting advancement in cancer therapy and diagnosis. Gold conjugated protein nanoparticles and protein nanoparticles itself were also produced in an radiation induced one pot process. Crosslinking and protein damage werea cessed by different techniques.

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  • IPEN-DOC 24834

    LODIS, ALINE M. ; SEIXAS, M.V. de S. ; VALENZUELA-DIAZ, FRANCISCO; GUVEN, OLGUN; MOURA, ESPERIDIANA A.B. . Structure and thermal/mechanical properties of poly (ϵ‐caprolactone)‐clay blend: synthesis and characterization of eva/clay flexible films treated by electron beam radiation. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: In the area of nanotechnology, polymer matrix based on nanocomposites have generated a significant amount of attention in the recent literature. The achieved results were at least initially viewed as unexpected (‘‘nano-effect’’) offering improved properties over that expected from thermal and mechanics predictions. This work presents the synthesis and characterization of EVA/Clay flexible films treated by electron beam radiation. EVA with 0.5 -3 wt.% of green Brazilian Clay addition were prepared by melt extrusion process, using a twin-screw extruder Haake Rheomex P332 with 16 mm and L/D = 25, from Thermo Scientific. Then, EVA/Clay nanocomposite was transformed into flexible films using a single-screw extruder with 25 mm diameter equipped with a flat die (laboratory line) and specimen test samples were obtained. Part of flexible film samples was submitted at electron beam radiation dose range 25-100 kGy using a 1.5 MeV electron beam accelerator, at room temperature in presence of air. The irradiated and non-irradiated samples were submitted to mechanical tests, XRD, UV-VIS, DSC, TG and FE-SEM analysis. The results showed significant changes in mechanical and thermal properties of EVA/CLAY flexible film due to clay addition and electron-beam irradiation. These results showed that it is possible to get interesting property in EVA flexible films by clay addition and electron-beam radiation treatment

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  • IPEN-DOC 24833

    KOMATSU, LUIZ G.H. ; OLIANI, WASHINGTON L. ; RANGARI, VIJAYA K.; PARRA, DUCLERC F. ; LUGAO, ADEMAR B. . Synthesis of ZnO for biocide activity on SEBS/PP applications. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Antimicrobial activity represents a challenge for scientific community. Polymer processing conditions impose temperature limitation for stability of biocide nanoparticles. In the present work, we evaluate ZnO synthesized in laboratory, utilizing Zn(NO3)26H2O as precursor. The main proposal is to improve the incorporation of this nanoparticle on SEBS/PP resulting on biocide material films. Before application on SEBS/PP, the nanoparticles was tested by reduction of forming colony units (CFU)(%), Dynamical Light Scattering (DLS) and Zeta potential. On CFU tests, all samples showed biocide properties. The samples with concentration of 1% showed the higher biocide effect on E.coli bacteria, in comparison of lower concentrations. The obtained material biocide was processed on SEBS/PP for obtaining of polymeric films with biocide activity and the new material was characterized by: forming colony units (CFU)(%), Differential Scanning Calorimetry (DSC), and Fourier Transformed Infrared (FTIR).

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  • IPEN-DOC 24832

    JARA, FERNANDO G.B. ; CRUZ, PEDRO V.D.; GALDINO, GABRIEL S.; CASINI, JULIO C.S.; SAKATA, SOLANGE K. ; FARIA JUNIOR, RUBENS N. . Thermal reduction of graphene oxide nanocomposite using a low temperature HDDR process for supercapacitors. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Recently, it has shown that the hydrogenation disproportionation desorption and recombination (HDDR) process can be an efficient method for the production of reduced graphene oxide for supercapacitors electrodes. The HDDR reduced graphene oxide was processed using a standard temperature (850 o C) for other materials applications. Some improvement in the specific capacitance and in the equivalent serial resistance has been obtained with this particular hydrogen thermal reduction process. The HDDR process has been considered a promising alternative method of reducing graphene oxide with efficiency and possibly in large scale production. A low temperature HDDR process was unreported for this purpose. In the present work, attempts of reducing a graphene oxide powder using a low temperature hydrogenation disproportionation desorption and recombination process (L-HDDR) has been carried out. A lower processing temperature in large scale production is significant as far as costs are concerned. Graphite oxide was prepared using a modified Hummers’ method and dispersed in ethanol, exfoliated using ultrasonication to produce Graphene Oxide (GO). Investigations have been carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The experimental results of L-HDDR processing graphene oxide powder using unmixed hydrogen at 400°C and relatively low pressures (<2 bars) have been reported.

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  • IPEN-DOC 24831

    GALDINO, GABRIEL S. ; FERREIRA SOBRINHO, LUIZA ; CRUZ, PEDRO V.D. ; CASINI, JULIO C.S.; SAKATA, SOLANGE K. ; FARIA JUNIOR, RUBENS N. . Electron beam irradiation of reduced graphene oxide-palladium nanocomposite for electrochemical supercapacitor. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Recent work has shown that palladium nanoparticle–graphene composite can be an efficient electrode material in energy storage applications in supercapacitors. These Pd-based supercapacitors showed remarkable properties with a maximum specific capacitance of 637 F g -1 and also exhibited excellent cycle life with 91.4% of the initial specific capacitance retained after 10000 cycles. Palladium nanoparticle decorated graphene composite was synthesized via a chemical approach in a single step by the simultaneous reduction of graphene oxide and palladium chloride from the aqueous phase using ascorbic acid as reducing agent. In the present work, electron beam irradiation has been investigated as an attempt to produce graphene-palladium nanocomposites. Graphite oxide was prepared using a modified Hummers’ method and dispersed in ethanol, exfoliated using ultrasonication to produce Graphene Oxide (GO) and dried for further analysis and processing. This material was thermic reduced in high vacuum (10 -6 mbar) at various temperatures (200-600 o C) and mixed in a solution with palladium. The samples were placed in a 50 ml beaker with Pd(NO 2 ) 2 2H 2 O and were irradiated with 300kGy , dose rate 1,6 kGy s -1 . Irradiation was carried out in an electron accelerator Dynamitron de 37,5 kW (E = 1,5 MeV, 25 mA) (Radiation Dynamics Inc.), The resulting irradiated material was characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). These investigations showed that a palladium graphene mixture for supercapacitors applications is formed by electron beam irradiation.

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  • IPEN-DOC 24830

    FELINTO, M.C.F.C. ; SALVADOR, F.F.S. ; FRANCISCO, L.H.C. ; BONTURIM, EVERTON ; BRITO, H.F.; MALTA, O.M.L.; TEOTONIO, E.E.S.. Rare earth compounds as smart materials to biological application. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Materials containing rare earth metals are receiving increasing attention due to its wide range of potential applications, including bioanalytical, images, dye-sensitized solar cells, nanobiotechnology, catalyses among others. The distinguished spectroscopic properties of lanthanides (intense emission bands, high color purity, long lifetime and high quantum efficiency) make them strong candidates for use as markers or bio- selective detectors. Besides the interest in developing nanoparticles ( NP ) associated with biological materials continues growing rapidly . This interest is mainly motivated by the desire to simultaneously exploit the properties of both the NP and biological components in new hybrid operating devices or materials that can be applied in strategic areas. In this work, we design various materials, synthesized and characterized in several laboratories that are part of the group fluoroimunoensaios inct - INAMI and NanoBio network and that have potential to use as biological markers .An attention to materials that emit in the regions of Vis and IR as the compound of Eu and Nd compounds, RE3 + compounds covered with silica and functionalized, RE3 + complexes dispersed in polymeric matrix and have sharp, etc. luminescence will be discussed. Also it will show these nanoparticles in - action , signaling biological materials at very low concentrations , on the order of nanomolar . The principal studies are connected to the diagnostic field and has been studied mainly Leishmania , PSA , LDL, sickle cell disease, estradiol and Chagas disease.

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  • IPEN-DOC 24829

    FELINTO, M.C.F.C. ; DIAS, C.L. ; FRANCISCO, L.H.C. ; BONTURIM, EVERTON ; BARBOSA, H.P.; BRITO, H.F.; MALTA, O.M.L.; TEOTONIO, E.E.S.. Preparation of luminescent Nd2(MoO4)3 amino-functionalized silica nanoparticles for bioconjugation. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Nanomaterials are used in many areas of biological research. Nanoparticles can be used as active components in various functional materials and devices of interest for bio-applications. Nanoparticles have long been signaled as a potential revolution in the way we probe and interact with biological materials and organisms. This is because they are small enough to interact with their environment at a molecular level, but strong enough to maintain useful properties such as luminescence over extended periods. However, the physical properties of the host materials with nanometer dimensions may differ markedly from those of their bulk counterparts due to the particle size-dependent influences such as structure disordering and surface defects. The development of materials incorporated in the silica has been studied since these materials exhibit intrinsic luminescent properties of the inorganic part and characteristics of the silica matrix. In the present work Nd2(MoO4)3 compounds incorporated into silica particles were prepared using a microwave synthesis procedure. Then, the material was dispersed in ethyl alcohol and functionalized with APTES: 3-aminopropyltriethoxisilane. The emission spectra show broad bands when compared with the emission spectra of the own rare earth compound. The narrow lines are assigned to 4f–4f transitions from the emitting 4 F3/2 level to the 4 I9/2 and, 4 I11/2 levels, centered around 915 and 1060 respectively.. Emission spectrum of the Nd2(MoO4)3 @ Si dispersion showed an enlargement of the bands. It is also observed the broadened peak of the 4 F3/2 4 I9/2, 4 I11/2 transitions in the luminescent amino-functionalized silica particles as compared with the core compound spectrum. These materials were conjugated to anti-IgG antibody and presented high efficient performance in detect human antigen. They can concluded that particles are potential candidates for development of the bioassays acting as a biomarker.

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  • IPEN-DOC 24828

    FAZOLIN, GABRIELA N. ; VARCA, GUSTAVO H.C. ; LUGAO, ADEMAR B. . The impact of physical-chemical parameters over the formation of papain nanoparticles crosslinked by radiation. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: With the advancement of research and use of nanotechnology in biomedical areas and application in different treatments the need for stable systems with low toxicity and null adverse effects becomes important. Within this context papain appears as an alternative biomolecule which is a proteolytic enzyme extract by the fruit of Carica papaya Linnaeus. Its already successfully applied in the pharmaceutical and biomedical area as a drug carrier and debriding agent for wounds. Recently, papain was developed in nanoscale using 50 Mm phosphate buffer (pH 7,2 ± 0,2), ethanol (20%, v/v) as cosolvent and 60Co as radiation source for gamma radiation (10 kGy) to promote protein crosslinking. This technique promotes papain nanoparticle sterilization and crosslinking in a single step showing that radiation is a promising technique for the development of nanoparticles for biomedical use. However, important parameters such as the influence of physical-chemical parameters over nanoparticle formation remains unexplored and unclear. Therefore, this work aimed to evaluate the influence of pH and temperature over papain nanoparticle formation including buffer molarity and different temperatures throughout the synthesis and irradiation process. Nanopapain was synthetized as above-mentioned however phosphate buffer was used in a range of 1 to 50 mM and ultrapure water in presence of ethanol and irradiated at 10 kGy. The influence of temperature was evaluated by performing the synthesis at -20, 0 and 20 °C. Additionally, it was verified the sterility of the material and its stability over time. The hydrodynamic radius and crosslinking were evaluated by dynamic light scattering and fluorescence measurements respectively. The pH range was influenced by buffer molarity, thus, lower molarities led to a final pH of 5 and the higher molarities around 7. Bityrosine formation was influenced by the pH range and increased when synthesis was performed near optimal pH (7 for papain), although particle size didn’t undergo any changes as a result of the pH changes. On the other hand, enzymatic activity was less affected by the process maintain about 80% of the native enzymatic activity only when synthesis was carried out in 50 mM phosphate buffer. With regard to temperature as the temperature increased the levels of crosslinking also increased in the order of 20>0ºC>-20ºC. In conclusion nanoparticle size was not influenced by the temperature shift. Concerning enzymatic activity samples irradiated under ice-cold conditions presented decreased bioactivity loss if compared to the samples irradiated at room temperature. After an evaluation of the results, the study revealed that samples synthetized with buffer molarity of 50 Mm (pH 7,2 ± 0,2) and 0ºC would promote higher crosslinking levels and less enzymatic activity decrease.

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  • IPEN-DOC 24827

    CORDEIRO, GUILHERME L. ; CAMARGO, ELAINE F. de ; USSUI, VALTER ; LIMA, NELSON B. de ; NETO, ALMIR O. ; LAZAR, DOLORES R.R. . Engineering graphene surface toward design of aggregation-resistant catalyst supports for advanced energy conversion. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Graphene has been considered an emerging fuel cell catalyst support due to its excellent chemical and electrical properties. The evaluation of the unit activity on each catalytic site (intrinsic) of low-loading supported metal nanoparticles (NPs), however, is often hampered by face-to-face aggregation of graphene sheets. Herein, we demonstrate the critical role of the expansion between sheets in a pivotal electrocatalytic process for green energy conversion through ethanol oxidation in acid medium. In order to reduce mass-transport resistances and incomplete utilization of the supported NPs, a one-step design strategy is proposed for tuning a desired physicochemical property of graphene: surface area. This step is based on the principle that the apparent activity is governed by the extrinsic activity, i . e ., the number of exposed active sites for a particular mass loading. Our design principle is achieved by a two-stage method involving a chemical delamination process of graphite (1) with an in situ surfactant functionalization/intercalation–reduction approach (2). As a result, not only an interlayer expansion was attained but also a short-ranged layered structure was assembled. This structural reorganization substantially affected the ethanol oxidation reaction (EOR) over platinum NPs. The unique nanoarchitecture provided a high density of EOR active sites, which incurred in a specific current value increased by about 2.5 and 5.4 times compared to platinum supported on state-of-the-art carbon black and restacked graphene, respectively.

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  • IPEN-DOC 24826

    CAMARGO, ELAINE F. de ; CORDEIRO, GUILHERME L. ; SANTOS, MONIQUE C.L. ; PEREIRA, CONRADO de V. ; USSUI, VALTER ; LIMA, NELSON B. de ; NETO, ALMIR O. ; LAZAR, DOLORES R.R. . Synthesis of cerium oxide nanopowders for improving catalysts electroactivity in direct ethanol fuel cells. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: The search for alternative direct ethanol fuel cell catalyst supports to improve platinum electrocatalysis requires the development of novel nanostructured conducting materials. In order to boost energy conversion efficiencies, high surface-area supports with enhanced oxophilicity have been addressed. This procedure might aid breaking the C–C bond and the poisoning of platinum by strongly adsorbed species coming from the dissociative adsorption of ethanol. In the present work, synthetic cerium oxide nanopowders were compared to state-of-the-art carbon black supports for the ethanol oxidation reaction (EOR). Cerium oxides were prepared via a simple chemical precipitation method using ammonium hydroxide as a precipitant agent and the effect of thermal treatment of the synthesized nanopowders was investigated. Microstructural analyses revealed an increase in crystallite size from 8.1 to 25.7 nm after heating from 400 to 800 °C, respectively. Supported catalysts containing 20 wt.% Pt were prepared by a sodium borohydride impregnation–reduction method, in aqueous solution, at room temperature. Electrochemical measurements of the EOR showed highest electrocatalytic activity over samples calcined at 400 °C as a result of a combinantion between an appropriate nano-scaled structure and oxygen transport in cerium oxide.

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  • IPEN-DOC 24825

    BATISTA, JORGE G.S. ; BARROS, JANAINA A.G. ; VARCA, GUSTAVO H.C. ; ROGERO, SIZUE O. ; CAVALCANTE, ADRIANA K. ; MAZIERO, JOANA S. ; ROGERO, JOSE R. ; LUGAO, ADEMAR B. . Evaluation of the in vitro and in vivo toxicity of gold nanoparticles synthesized by green nanotechnology. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Researchers and laboratories around the world have studied gold nanoparticles. In medicine, several studies demonstrate the applicability of gold nanoparticles (AuNPs) in the treatment and diagnosis of cancer. Green nanotechnology uses phytochemical agents to synthesize and stabilize nanoparticles. The phytochemical epigallocatechin-gallate (EGCG) reduces and stabilize gold nanoparticles by functionalizing the surface of the molecule. Such chemical groups allow binding to overexpressed receptors on some types of tumors as demonstrated in studies performed with PC3 prostate cancer cells. With the advancement of nanotechnology, a large number of nanoparticles are produced on a daily basis. However apart from their possible applications it is necessary to evaluate the environmental impact of these molecules as well as find ways for proper disposal. The embryonic zebrafish (Danio rerio) trial has recently emerged as an interesting method for evaluating in vivo nanotoxicity providing a more complex system analysis than in typical cell cultures and less expensive if compared to large-scale biocompatibility studies performed in rats and mice. The objective of this study was to evaluate the in vitro and in vivo toxicity of EGCG-AuNPs by means of the cytotoxicity by neutral red uptake methodology according to the International Standard Organization [ISO 10993-5, 2009] and in vivo test based on the OECD guideline on Fish Embryo Toxicity Test (FET) (OECD, 2013). The spectrophotometric band at 535 nm observed is characteristic of the formation of AuNPs. Nanoparticles synthesized with EGCG presented a size of 32 ± 4 nm as determined by transmission electron microscopy and the hydrodynamic diameter of these particles was about 60 ± 18 nm obtained by dynamic light scattering. The EGCG-AuNPs showed no cytotoxicity up to 4.2 μg.L-1. In the FET test regarding the acute ecotoxicity assay the LC50/96 hours revealed no toxicity at concentrations up to 1.8 mM.

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  • IPEN-DOC 24824

    BARTOLOMEI, SUELLEN S.; MACHADO, MESSIAS S.; SANTANA, JULYANA G. ; MOURA, ESPERIDIANA ; WIEBECK, HELIO. Recycling of plastic cups and packaging of EPS to obtain nanocomposite with nanoclay and plaster. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Polystyrene is a polymer defined as brittle due to its mechanical properties, but still widely used industrially for its cost and processability. However, the fragility restricts its use in engineering applications. To improve the material, the addition of a plasticizer is recommended, because it acts between the polymer chains increasing its mobility and delaying the growth of cracks. Another method for improving the mechanical properties of a polymer is the use of a reinforcing phase thereby generating a nanocomposite. In this work the polystyrene of disposable plastic cups and expanded polystyrene packages were recycled using ethyl acetate. Together with the solvent, glycerin was added to plasticize the recycled polymer. Therefore, a solution was made containing recycled polystyrene and glycerin, this solution was allowed to stand until all solvent evaporated and a rigid film was obtained. Then, to improve the mechanical properties, three types of composite were prepared by melt extrusion, using a twin screw extruder machine. First, the recycled polystyrene of the cups was mixed with nanoclay (5% wt), afterwards the recycled polystyrene of the cups was mixed with nanoclay (5% wt) and gypsum (5% wt) and, in the third composite, it were mixed the recycled expanded polystyrene with gypsum particles (10% wt). Specimens were injected and tensile tests were performed to compare the mechanical properties of the composites obtained.

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  • IPEN-DOC 24823

    ALCANTARA, MARA T.S. ; COUTINHO, CAMILA M. ; OLIVEIRA, MARIA J.A. ; MUNHOZ, MARA M.L. ; LUGAO, ADEMAR B. . Obtaining of a hydrogel gel dressing of PVP with nanosilver for deep and complex wounds. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, 27-30 de novembro, 2017, Guarujá, SP. Abstract... 2017.

    Abstract: Introduction Chronic and some acute wounds of difficult treatment that challenge medical and nursing teams are classificadas como Complex wound (Ferreira et al., 2006). Due to the long cicatrization time and successive relapses, cause a problem social on patients' lives and economic a major impact on the health system (Azoubel et al., 2017). Throughout the world there has been a growing interest in the use of hydrogels for application as dressings in view that they are able to maintain the humidity of the wound, favoring the epithelialization of lesions and favoring the relief of pain. On the other hand, silver is an agent that has been used since ancient times, but it has been replaced after the discovery of antibiotics. However, with the advent of bacterial resistance to antibiotics and the development of nanotechnology, it has regained notoriety, since the clinical incidence of silver resistance remains low (Chopra, 2007).In addition to its bactericidal properties, silver nanoparticles (AgNPs) also have anti-inflammatory properties, which, allied to hydrogels’ advantages of maintaining moisture in the wound, represent a great advantage for use as a dressing. However, conventional dressings do not address the need for direct contact with the wound when this is a deep wound. The objective of this work was to obtain a hydrogel gel with silver nanoparticles for wound dressing, synthesized in situ by using ionizing radiation for gelation (crosslinking of PVP-Ag+ aqueous solution), synthesis of the AgNPs and simultaneous sterilization of the final product, able to fill the cavity of deep wounds, thus allowing the direct contact of the dressing with the lesioned walls. Methodology The gel was prepared from the mixture of PVP with plasticizers, water, and silver ions; next, the mixture was irradiated / sterilized by gamma-irradiation from a 60-Co source at a dose of 20 kGy. . Results The result of this work is a viscous and transparent gel (Fig. 1), easy to be applied, able to control pain since it reduces the local temperature due to evaporation of water. Fig. 1 - Hydrogel gel of PVP with silver nanoparticles for wound dressing. The studies are being continued with the aim of evaluating its stability and bactericidal activity.

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  • IPEN-DOC 24693

    OLIVEIRA, L.N. de ; NASCIMENTO, E.O. do; SCHIMIDT, F.; ANTONIO, P.L. ; CALDAS, L.V.E. . Assessment of Ethylene Vinyl-Acetato Copolymer (EVA) samples bombarded by gamma radiation via linearity analyses. Journal of Physics: Conference Series, v. 975, p. 1-4, 2018. DOI: 10.1088/1742-6596/975/1/012041

    Abstract: Materials with the potential to become dosimeters are of interest in radiation physics. In this research, the materials were analyzed and compared in relation to their linearity ranges. Samples of ethylene vinyl-acetate copolymer (EVA) were irradiated with doses from 10 Gy to 10 kGy using a 60Co Gamma-Cell system 220 and evaluated with the FTIR technique. The linearity analyses were applied through two methodologies, searching for linear regions in their response. The results show that both applied analyses indicate linear regions in defined dose interval. The radiation detectors EVA can be useful for radiation dosimetry in intermediate and high doses.

    Palavras-Chave: copolymers; ethylene; polymerization; vinyl acetate; gamma radiation; cobalt 60; gamma sources; fourier transform spectrometers; acetates

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  • IPEN-DOC 24822

    WEBLER, G.D.; RODRIGUES, W.C.; SILVA, A.E.S.; SILVA, A.O.S.; FONSECA, E.J.S.; DEGENHARDT, M.F.S.; OLIVEIRA, C.L.P.; OTUBO, L. ; BARROS FILHO, D.A.. Use of micrometric latex beads to improve the porosity of hydroxyapatite obtained by chemical coprecipitation method. Applied Surface Science, v. 436, p. 141-151, 2018. DOI: 10.1016/j.apsusc.2017.11.218

    Abstract: Hydroxyapatite is one of the most important biomaterials whose application mainly extends to implants and drug delivery. This work will discuss the changes in the pore size distribution of hydroxyapatite when there are latex beads present during the synthesis. These changes were monitored using different techniques: small angle X-ray scattering, X-ray diffraction, thermal gravimetrical analysis, N2 adsorption, scanning and transmission electron microscopy. Latex beads and hydroxyapatite form a single nanocomposite with well-distinguished inorganic and organic phases. Latex bead removal in the temperature range of 300–600 ◦C did not modify the original crystalline structure of hydroxyapatite. However, the latex beads favored an increase in the adsorption capacity of mesopores at temperatures higher than their glassy transition (Tg). The main result of this research work consists on the increase of surface area and pore size distribution obtained after the removal of latex beads template. Latex beads have been used in a different approach changing the porosity of hydroxyapatite scaffolds not only introducing new routes for cell integration but also broadening the pore size distribution which can result in a more high efficiency for drug release in living cells.

    Palavras-Chave: apatites; hydroxy compounds; biological materials; composite materials; surface properties; chemical reactions; synthesis

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  • IPEN-DOC 24821

    JIMENEZ-VILLAR, E. ; XAVIER, M.C.S.; RAMOS, J.G.G.S.; WETTER, N.U. ; MESTRE, VALDECI; MARTINS, WELITON S.; BASSO, GABRIEL F.; ERMAKOV, VICTOR A.; MARQUES, FRANCISCO C.; SA, GILBERTO F. de. Localization of light: beginning of a new optics. In: GALVEZ, ENRIQUE J. (Ed.); ANDREWS, DAVID L. (Ed.); GLUCKSTAD, JESPER (Ed.) Complex Light and Optical Forces, 12th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 1054905-1 - 1054905-11. (SPIE Proceedings Series, 10549). DOI: 10.1117/12.2288993

    Abstract: In recent years, there has been a dramatic progress in the photonics field of disordered media, ranging from applications in solar collectors, photocatalyzers, random lasing, and other novel photonic devices, to investigations into fundamental topics, such as localization of light and other phenomena involving photon interactions. Anderson localization of light is an open researcher frontier, which has greatly attracted the attention of researchers in the past few decades. In this work, we study the transport of light in a strongly disordered optical medium composed by core-shell nanoparticles (TiO2@Silica) suspended in ethanol solution. We demonstrate the crossover from a diffusive transport to a localization transition regime as TiO2@Silica nanoparticle concentration is increased. A striking phenomenon of enhanced absorption, mainly near the input border, arises at the localization transition, from which an increase of refractive index was inferred. An increase of the density of localized states and absorption near the input border is reported when the incidence angle is increased. The specular reflection, measured for the photons that enter the sample, is considerably lower than the effective internal reflection undergone by the coherently backscattered photons in the exact opposite direction, indicating a nonreciprocal propagation of light (parity-symmetry breaking). A theoretical simulation, performed through random-matrix theory, agrees satisfactorily with the experimental results, showing the generality of this approach to address transport phenomena.

    Palavras-Chave: light transmission; light sources; visible radiation; titanium oxides; nanoparticles; silica; backscattering; photons

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