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  • IPEN-DOC 26967

    SANTOS, VINICIUS T. dos; SANTOS, GIVANILDO A. dos; NAKAMOTO, FRANCISCO Y.; SILVA, MARCIO R. da; FRANCO, ANTONIO T.R.; COUTO, ANTONIO A. . Influência das variáveis térmicas de solidificação na microestrutura e dureza da liga bronze alumínio níquel CuAl10Ni5Fe5 / Influence of thermal variables of solidification on the microstructure and hardness of nickel aluminum bronze alloy CuAl10Ni5Fe5. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICAÇÃO, 9., 26-29 de junho, 2017, Joinville, SC. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2017.

    Abstract: O objetivo deste trabalho é obter correlações entre a microestrutura e dureza da liga Bronze Alumínio Níquel CuAl10Ni5Fe5 em função das variáveis térmicas de solidificação. Estas variáveis são responsáveis pela formação das fases e intermetálicos presentes no Bronze Alumínio Níquel, os quais interferem diretamente nas propriedades mecânicas do material. A liga CuAl10Ni5Fe5 foi solidificada em um dispositivo com sistema ascendente sob condições não-estacionárias de fluxo de calor. O calor foi extraído direcionalmente através de uma base de aço ABNT 1020 refrigerada a água. No que diz respeito à análise da microestrutura, utilizou-se microscopia eletrônica de varredura, permitindo a verificação das morfologias das fases e intermetálicos. As variáveis térmicas de solidificação geram resultados referentes à velocidade de deslocamento da isoterma liquidus e à taxa de resfriamento. A propriedade mecânica foi avaliada por meio de ensaio de dureza em toda extensão longitudinal da peça solidificada, a qual apresenta a formação das fases e intermetálicos formados por meio das condições de solidificação impostas pelo sistema metal/molde. A microestrutura e dureza são correlacionadas com as variáveis térmicas de solidificação, enfatizando a importância das taxas de resfriamento na formação das fases e intermetálicos da liga CuAl10Ni5Fe5. O resultado deste trabalho demonstra que, quanto maior a taxa de resfriamento, maior é o resultado obtido de dureza.

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  • IPEN-DOC 26961

    SANTOS, CAMILA F.R.T.T. ; SILVA, TATIANE B. de S.C. da ; COTRIM, MARYCEL E.B. ; PIRES, MARIA A.F. . Fatores de emissão atmosférica e análise de significância aplicada na gestão da qualidade do ar no campus do IPEN/CNEN-SP / Atmospheric emission factors and significance analysis applied to the air quality management in the IPEN / CNEN-SP campus. In: ENCONTRO INTERNACIONAL SOBRE GESTÃO EMPRESARIAL E MEIO AMBIENTE, 18., 5-6 de dezembro, 2016, São Paulo, SP. Anais... São Paulo, SP: Faculdade de Economia, Administração e Contabilidade da Universidade de São Paulo - FEA USP, 2016.

    Abstract: Devido ao compromisso com a melhoria do meio ambiente, aliado às crescentes exigências dos órgãos ambientais, e a necessidade de identificar a contribuição de cada atividade/processo desenvolvido em institutos de pesquisas, quanto ao impacto destes à qualidade do ar, este trabalho tem a finalidade de desenvolver um modelo de inventário e aplicar uma metodologia de cálculo, que permita estimar a emissão de poluentes atmosféricos, decorrentes das atividades dos centros de pesquisa e desenvolvimento do Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP). O estudo foi motivado pela ausência de metodologias de cálculo de emissões atmosféricas específicas para fontes fixas como capelas de exaustão. Para a elaboração dos cálculos foram adotados os fatores de emissão e a equação descrita na AP-42 da EPAEnvironmental Protetion Agency. Foram utilizadas como abordagens de cálculo de emissões: a) Mensuração direta (por meio do inventário de emissões atmosféricas); e b) Estimativa de emissões (utilizando estimativa da taxa de emissão calculada a partir do fator de emissão apropriado). Como produto final obteve-se um inventário de emissões atmosféricas de fontes fixas da instituição e estimou-se a emissão atmosférica do Centro de Química e Meio Ambiente (CQMA) a fim de estabelecer de forma efetiva o Programa de Monitoramento e Controle de Emissões Atmosféricas (PMEA – IPEN), servindo de base para outras instituições de Pesquisa, Desenvolvimento & Inovação.

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  • IPEN-DOC 26954

    GONÇALES, LETICIA dos R.; FERRAZ, LUCAS C. de C.; CORREA, OLANDIR V. ; ANTUNES, RENATO A.. Estudo da influência do tamanho de grão sobre o comportamento de corrosão da liga de magnésio AZ91D / Study of grain size influence on the corrosion behavior of AZ91D magnesium alloy. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 71.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALURGICA, DE MATERIAIS E DE MINAS, 16., 26-30 de setembro, 2016, Rio de Janeiro, RJ. Anais... São Paulo, SP: Associação Brasileira de Metalurgia, Materiais e Mineração, 2016. p. 1326-1334.

    Abstract: A liga AZ91D apresenta 9%pAl e 1%pZn e pode ser submetida a tratamento térmico de solubilização seguido de envelhecimento para melhoria de propriedades mecânicas por meio de precipitação da fase beta-Mg17Al12. Esta fase, porém, pode ter efeitos distintos sobre o comportamento de corrosão da liga. Buscando estudar a influência do tamanho de grão da matriz alfa e a presença de precipitados beta sobre a resistência à corrosão da liga AZ91D, este trabalho utilizou lingotes com estrutura bruta de fusão na obtenção de amostras solubilizadas, laminadas a frio e então envelhecidas, para subsequente análise microestrutural e do comportamento de corrosão. A solubilização ocorreu a 445ºC por 24h e foi efetiva em dissolver quase completamente a fase beta. A laminação levou a uma redução de 20% da espessura das amostras e de 400 para 130 μm o tamanho de grão médio, após envelhecimento. O envelhecimento feito a 200ºC em 2 e 24h permitiu a precipitação de fase beta em maior quantidade e melhor distribuição por contornos de grão em relação às amostras fundidas ou solubilizadas. Ensaios de imersão foram realizados, apontando uma leve queda na taxa média de corrosão quando se lamina a amostra, enquanto as amostras solubilizadas (sem fase beta) mostraram maior susceptibilidade à corrosão. Assim, é possível indicar que o refinamento de grãos é benéfico ao formar uma rede de proteção em ligas de magnésio AZ91D, apesar de introduzir defeitos gerados pela laminação.

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  • IPEN-DOC 26953

    GOMES, MAURILIO P. ; SANTOS, IGOR P. dos ; REIS, LUIS A.M. dos ; COUTO, CAMILA P. ; MUCSI, CRISTIANO S. ; COLOSIO, MARCO A.; ROSSI, JESUALDO L. . Characterization of sintered valve seat inserts obtained with AISI M2 high-speed steel after air quenching / Caracterização de insertos para assentos de válvulas sinterizados obtidos com o aço rápido AISI M2 depois de temperados ao ar. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 72.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALURGICA, DE MATERIAIS E DE MINAS, 17., 02-06 de outubro, 2017, São Paulo, SP. Anais... São Paulo, SP: Associação Brasileira de Metalurgia, Materiais e Mineração, 2017. p. 993-1000.

    Abstract: The aim of this work was to heat treat and characterize sintered valve seat inserts (VSI). The powder metallurgy route was the only way found to substitute cobalt and lead, used in the VSI original alloy, due to their high cost and toxicological effect, respectively. The studied VSI was obtained with AISI M2 high-speed steel powder mixed with iron powder and other additives such as manganese sulphide, graphite, zinc stearate, carbides and copper, which was added by metallic infiltration. All the VSI were air quenched and double tempered, for one hour each, at seven different equidistantly temperatures, ranging from 100 °C up to 700 °C. The physical and mechanical properties were evaluated by means of the VSI apparent density, apparent hardness and crush radial strength. The chemical composition was determined through gas analysis, for the light elements such as carbon and sulfur, and energy dispersive X-ray fluorescence spectrometry for other elements. Microstructural characterization was performed with the support of scanning electron microscopy and energy dispersive spectroscopy. Regarding the VSI final application, the best results were achieved with the inserts air quenched and double tempered at 600 °C.

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  • IPEN-DOC 26951

    SANTOS, ADIMIR dos ; SILVA, GRACIETE S. de A. e . The impact of the new nuclear data libraries on the isothermal reactivity coefficient determination. In: INTERNATIONAL CONFERENCE ON MATHEMATICS AND COMPUTATIONAL METHODS APPLIED TO NUCLEAR SCIENCE AND ENGINEERING, April 16-20, 2017, Jeju, Korea. Proceedings... Daejeon, Korea: Korean Nuclear Society, 2017.

    Abstract: The impact of the new released evaluations for 235U, 238U, 16O, and S(α,β) for hydrogen bound water, in the determination of the isothermal reactivity coefficient of thermal reactors fueled with slightly enriched uranium is addressed in this work. The experiment to serve as a benchmark for this kind of reactor response is the inversion point of the isothermal reactivity coefficient of the IPEN/MB-01 reactor which was recently approved to be included in the IRPhE handbook. The theoretical analyses have been performed employing the coupled NJOY/AMPX-II/TORT systems. The analyses reveal that the major impacts are due to new data of 235U and to those of S(α,β) for hydrogen bound in water. The (C-E)/E values when considering the new data from these libraries show an excellent progress in the theoretical determination of this very important reactor response. The new data for 238U and 16O show very little impact on the analysis. This work supports the developments recently adopted in the generation of the new nuclear data libraries for 235U and for the S(α,β) for hydrogen bound in water.

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  • IPEN-DOC 26946

    ANDRADE, GABRIEL M.; SILVA, LEONARDO G.A. ; REZENDE, MAIRA de L.. Efeito da radiação ionizante no Etileno Propileno Dieno (EPDM) / Effect of ionizing radiation in Ethylene Propylene Diene (EPDM). In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 1917-1921.

    Abstract: A substituição do processo de vulcanização ou reticulação da borracha para a produção de artefatos de diversos segmentos torna-se interessante do ponto de vista ambiental e financeiro, pois evita o emprego de enxofre e de peróxidos. A radiação ionizante empregada em elastômeros pode ocasionar diversas alterações estruturais e, entre essas possibilidades destaca-se a reticulação. Este trabalho tem por objetivo avaliar as alterações provocadas no EPDM após aplicação de diferentes doses de radiação proveniente de feixes de elétrons, buscando verificar a possibilidade deste processo na substituição da vulcanização convencional aplicada em borrachas. Os efeitos da radiação foram investigados por meio de ensaios mecânicos e determinação da densidade de reticulação. Os resultados sugerem que houve cisão de cadeias, bem como a formação de novas ligações entre as macromoléculas, variando a intensidade conforme a dose aplicada, o que indica a possibilidade de os feixes de elétrons substituírem a vulcanização convencional.

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  • IPEN-DOC 26945

    LEVY, D. ; SORDI, G.M.A.A. ; VILLAVICENCIO, A.L.C.H. . Divulgación científica: un desafío y una necesidad para aproximar ciencia y sociedad. In: SIMPOSIO INTERNACIONAL SOBRE EDUCACION, CAPACITACION, EXTENSION Y GESTION DEL CONOCIMIENTO EN TECNOLOGIA NUCLEAR, 2., 13-17 de novembro, 2017, Buenos Aires, Argentina. Anais... 2017.

    Abstract: La Irradiación de alimentos trae grandes contribuciones a la seguridad alimentaria, además de los impactos en las esferas social y económica del país. En Brasil, sin embargo, aún es grande el desconocimiento: miedos y preconceptos infundados tiemblan la confianza del consumidor. Investigadores del IPEN emprendieron una investigación ante el público en general. Los mayores ejemplos de aplicaciones de la tecnología nuclear parecen ser, en el imaginario popular, armas de destrucción masiva y accidentes nucleares. Entre las mayores preocupaciones de los entrevistados, están la cuestión de la seguridad en relación a la salud, exposición a la radiación y contaminación del medio ambiente. En 2016 se inició una acción para la divulgación científica a gran escala. En la llamada Sociedad de la Información, la acción se centra en el desarrollo de cursos virtuales destinados al público en general. El proceso involucró una amplia investigación sobre las posibilidades de acceso a Internet en los domicilios brasileños y perspectivas futuras. Los cursos tienen como objetivo llevar al conocimiento del público cuestiones pertinentes a la irradiación de alimentos de la agricultura a la mesa del consumidor, entre las cuales, un mini curso completamente destinado a la comunicación de la protección radiológica, una vez que la investigación apunta entre las mayores preocupaciones de la población la Seguridad, contaminación y efectos maléficos de la radiación. Esta acción pretende proporcionar al público en general material confiable y de fácil comprensión para la diseminación del conocimiento en los más diversos sectores de la sociedad. La alimentación es una de las grandes cuestiones brasileñas y la irradiación de alimentos es una técnica segura y confiable para responder a esta demanda. Los consumidores hacen juicios intuitivos según su percepción de riesgo y el desconocimiento conduce a miedos infundados y conclusiones equivocadas. Se espera con esta iniciativa acercar la sociedad y la comunidad científica. Una acción ciudadana para promover la conciencia crítica llevando al ciudadano a cuestionar la realidad, interpretar las informaciones de la mídia y construir opiniones científicamente fundamentadas.

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  • IPEN-DOC 26904

    GIOVEDI, C.; MARTINS, M.R.; ABE, A. ; MUNIZ, R.O.R. ; GOMES, D.S. ; SILVA, A.T. . Fuel performance assessment of enhanced accident tolerant fuel using iron-based alloys as cladding. In: TOPFUEL, 30 September - 04 October, 2018, Prague, Czech Republic. Proceedings... Brussels, Belgium: European Nuclear Society, 2018.

    Abstract: In the framework of the Enhanced Accident Tolerant Fuel (EATF) program, one important tool to assess the behaviour of new materials under irradiation is the use of fuel performance codes. For this, it is necessary to modify conventional fuel performance codes to introduce the properties of the materials to be studied. The aim of this paper is to present some preliminary results obtained using modified versions of the FRAPCON code adapted to evaluate the performance as cladding of two different types of iron-based alloys as cladding: stainless steel (AISI 348), and FeCrAl alloy, including a preliminary sensitivity analysis. The results obtained using the modified versions of the codes were compared to those obtained for zirconium-based alloys using the original code version. The results have shown and confirmed that iron-based alloys are one of the promising candidates to be used as EATF cladding in PWR.

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  • IPEN-DOC 26903

    LEVY, D.S. ; RAMOS, F.C.; SORDI, G.M.A.A. . The impact of wrong mass media communication on citizens' perception of radiation risks. In: CONGRESO REGIONAL DE SEGURIDAD RADIÓLOGICA Y NUCLEAR, 11th, April 16-20, 2018, La Habana, Cuba. Proceedings... 2018.

    Abstract: In Knowledge Society, Internet and mass media contribute to build an inclusive informed society, providing information about all fields of knowledge. Nevertheless, nuclear sciences remain a mystery for a great fraction of the Brazilian population. Controversies on the biological effects of radiation distort and confuse public's perceptions of radiation risks and benefits. Internet reports that the exposure to indoor radon is a risk factor for lung cancer. Internet reports that the radioactive monazitic sand brings health benefits. It is not easy for the general public to understand contradictions and to identify reliable sources. Scientific community is expected to communicate about the impacts of ionizing radiation in daily life. Nevertheless, the public does not read highly specialized papers. There seem to be a gap between society and the scientific community. On the other hand, anti-nuclear information seems to be easily understood. This paper discusses wrong mass media information delivered all over the country, for kids and adults, in very simple language, through cartoons, comics books, newspapers and educational sites, among others. The article brings examples of newspapers errors due to misinformation, anti-nuclear didactic material plenty of omissions and wrong information delivered to children. People fear what they do not understand. People fear the harmful effects of ionizing radiation to human health and the environment. Risk perception and risk acceptance are a matter of education and properly communication. It is a must to invest in properly scientific divulgation about the risks and benefits of nuclear sciences that impact in citizens´ everyday life, such as medical applications, industrial applications and nuclear power generation.

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  • IPEN-DOC 26902

    COUTO, CAMILA P. ; COSTA, ISOLDA ; PANOSSIAN, ZEHBOUR; COLOSIO, MARCO A.; CAMPOS, LUIZ G.F.P. de; ROSSI, JESUALDO L. . Corrosion resistance and adhesion evaluation of press hardened steel 22MnB5 coated with AlSi and ZnNi in cyclic corrosion testing. In: CONGRESSO BRASILEIRO DE CORROSÃO, 38.; INTERNATIONAL CORROSION MEETING, 7th; CONBRASCORR PARA INSPETORES DE PINTURA, 2.; CONCURSO DE FOTOGRAFIA DE CORROSÃO E DEGRADAÇÃO DE MATERIAIS, 21.; EXPOSIÇÃO DE TECNOLOGIAS PARA PREVENÇÃO E CONTROLE DA CORROSÃO, 37., 14-18 de maio, 2018, São Paulo, SP. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Corrosão, 2018. p. 1-6.

    Abstract: AlSi coating has been the most applied on press hardening steels - PHS. However, alternative coatings such as Zn-based alloys are under investigation. This paper has the objective of evaluating the corrosion resistance of the 22MnB5 steel, coated either with hot-dip AlSi or electroplated ZnNi, by means of cyclic corrosion test. Automotive parts of ZnNi coated PHS steel were tested in two different conditions: after hot stamping, and after hot stamping plus sandblasting. Other parts coated with AlSi were evaluated just in the after hot stamping condition. The cyclic corrosion test results showed that all metallic coated samples had excellent corrosion performance. However, the ZnNi coated in the as hot stamped condition, presented the best corrosion performance during testing. Surface coating cracks were found in all parts. Moreover, the adhesion was evaluated after 28 and 68 cycles in creepback area and the results showed that there was no loss of adhesion after the cyclic corrosion tests. The corrosion resistance results pointed that the electroplated ZnNi is a potential alternative to AlSi coating.

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  • IPEN-DOC 26901

    QUINI, J.G.; MARINUCCI, G. . Evaluation of urethane adhesive-composite joints under different environmental conditions. In: EUROPEAN CONFERENCE ON COMPOSITE MATERIALS, 18th, June 24-28, 2018, Athens, Greece. Proceedings... Patras, Greece: European Society for Composite Materials, 2018. p. 1-6.

    Abstract: Structural adhesives technology has changed the concept of joints bonding different materials in a unique solid assembly and making them part of the structures. These joints not only increase strength and stiffness but also reduce weight, which is important, for instance, for vehicles and airplanes. The present study reports the results of applying urethane structural adhesives in automotive components. RTM, SMC, ABS thermoplastic and galvanised steel samples was evaluated under temperaturem time, humidity and destilled water. The results show very good adherence between the adhesive and the substrates under these conditions.

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  • IPEN-DOC 26900

    BELCHIOR JUNIOR, A. ; SANTOS, A.A.C. dos; FREITAS, R.L.; SOARES, H.V.; JUNQUEIRA, F.C. ; MANTECON, J.G. ; MATTAR NETO, M. ; MENZEL, S.C. ; TORRES, W.M. ; UMBEHAUN, P.E. . Analytical and experimental analysis on safety related aspects of the RMB research reactor. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS, November 25-29, 2019, Buenos Aires, Argentina. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2019. p. 1-8.

    Abstract: This paper presents some numerical and experimental safety related activities developed at the Brazilian Multipurpose Reactor (RMB) project by CNEN research institutes. Brief comments on the models and results are presented with emphasis to their relation to the safe design and operation of the reactor. Thermal-hydraulic analysis for Siphon Breaker of the Core Cooling System (CCS); pools hot water layer; core chimney of CCS and spent fuel transport cask are presented, showing results, advantages, difficulties and drawbacks for each analyzed case. All are very distinct cases, involving phenomena that range from two-phase flow and thermal-stratification to lead melting. Beside the one-dimensional thermal hydraulic system Code RELAP5, Computational Fluid Dynamics (CFD) is shown to play an important role in the analysis being performed as it can detail the flow and temperature fields of complex components and phenomena, which are extremely difficult to model analytically or experimentally. Two experimental circuits designed to test RMB fuel elements performance are also presented.

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  • IPEN-DOC 26899

    SANTAELLA, CESAR R.K. ; CORREA, OLANDIR V. ; COTINHO, SAMUEL P.; PILLIS, MARINA F. . Propriedades das camadas termodifundidas de boro e lantânio no aço AISI 1045. In: INTERNATIONAL FORGING CONFERENCE, 23rd; NATIONAL SHEET METAL FORMING CONFERENCE, 22nd; INTERNATIONAL SHEET METAL FORMING CONFERENCE, 9th; BRDDRG CONGRESS, 6th; INTERNATIONAL CONFERENCE ON MATERIALS AND PROCESSES FOR RENEWABLE ENERGIES, 9th; INTERNATIONAL CONFERENCE ON SURFACE ENGINEERING IN MATERIAL FORMING, 2nd, October 2-4, 2019, Porto Alegre, RS. Proceedings... 2019.

    Abstract: A boretação é um processo termoquímico de difusão de boro no estado sólido que tem por objetivo aumentar a resistência ao desgaste através da formação de uma camada dura de boretos de ferro na superfície do aço. As propriedades dessas camadas podem ser alteradas com a difusão combinada de boro com outros elementos químicos simultaneamente, como por exemplo o alumínio, para elevar a resistência à oxidação, ou o vanádio, para elevar a resistência ao desgaste superficial. Neste trabalho são apresentados os resultados obtidos com a difusão combinada de boro e lantânio.

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  • IPEN-DOC 26898

    SABUNDJIAN, INGRID T. ; NEGRAO, BIANCA G. ; SÁ, ANA P.N. de ; VILLAVICENCIO, ANNA L.C.H. . Analise microbiológicas de fermento biológico seco processado por radiação gama. In: CONGRESSO BRASILEIRO DE CIÊNCIA E TECNOLOGIA DE ALIMENTOS, 26., 13-16 de agosto, 2018, Belém, PA. Anais... Belém, PA: Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2018. p. 6007-6014.

    Abstract: O objetivo do trabalho foi identificar se houve alteração no crescimento de UFC em placa e na viabilidade de leveduras e bactérias totais em fermento biológico seco tratado por diferentes doses de radiação gama e determinar a dose D10 para bactérias Totais e Leveduras a fim de analisar se o processamento promoveu algum benefício sem causar inviabilidade do mesmo. As diferentes amostras de fermento biológico foram irradiadas com doses de 0 (controle); 0,5; 1; 2 e 3kGy no Centro de Tecnologia das Radiações do (IPEN/CNEN – SP) em fonte de 60Co (Gammacell-220), com taxa de dose de 3,51kGy/h. O aumento da dose de radiação provocou uma diminuição na contagem de UFC de leveduras e de bactérias totais, bem como, na frequência de células viáveis de leveduras. A dose de radiação necessária para eliminar 90% da população leveduriforme ficou entre 1,10 e 2,23kGy e para a população bacteriana variou entre 2,31 e 2,95kGy. Nos resultados são demonstrados claramente os pontos negativos da aplicação de radiação ionizante em fermento biológico seco, pois o intervalo de D10 encontrado para bactérias totais é superior ao encontrado para leveduras. Sendo assim, torna-se inviável a utilização deste recurso para a melhora da qualidade do produto.

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  • IPEN-DOC 26897

    NEGRAO, BIANCA G. ; VILLAVICENCIO, ANNA L.C.H. ; ARTHUR, VALTER. Ionizing radiation as a phytosanitary treatment in Zea mays L. var. everta. In: CONGRESSO BRASILEIRO DE CIÊNCIA E TECNOLOGIA DE ALIMENTOS, 26., 13-16 de agosto, 2018, Belém, PA. Anais... Belém, PA: Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2018. p. 6022-6028.

    Abstract: Quarantine treatment has been used to provide protection against pests by eliminating the stages evolutionary cycle that may be associated with the product. Popcorn is used in the food industry in the form of dry beans and is an economic option for producers and their sale generates foreign exchange worldwide. The aim of this work is to evaluate the effects of gamma radiation on seeds of popcorn (Zea mays L. var. everta). The seeds was be purchased in the retail trade of São Paulo city, later was be infested in the Laboratory of Food Irradiation at IPEN, then was be submitted to different doses of gamma radiation: 0, 25, 50, 75 and 100 Gy. A Gammacell-220 at 60Co source at a dose rate of 1.4 kGy / hr at the Technology Center of Radiation (CTR) IPEN-CNEN / SP. Each treatment was consisting of 3 replicates with 100 grams of popcorn kernels. Samples was be packed and stored at a temperature of 25 ± 2 ° C and relative humidity of 70 ± 5%. By the results, it can conclude that the dose of 75 Gy can be indicated to control insects Sitophilus zeamais in popcorn.

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  • IPEN-DOC 26896

    KOIKE, AMANDA C.R. ; SÁ, ANA P.N. de ; ARAUJO, ELIAS da S.; ALMEIDA-MURADIAN, LIGIA B. de; VILLAVICENCIO, ANNA L.C.H. . Evaluation of carotenoids in edible flowers processed by radiation. In: CONGRESSO BRASILEIRO DE CIÊNCIA E TECNOLOGIA DE ALIMENTOS, 26., 13-16 de agosto, 2018, Belém, PA. Anais... Belém, PA: Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2018. p. 5518-5524.

    Abstract: The use of flowers in the gastronomy has been growing in recent years, the world market for edible flowers is in full expansion, this kind of flower ensure a special note in the taste and in the decoration, and improve the nutritional aspects when added in food products. Its beneficial properties in health maintenance are also recognized, requiring new approaches to improve its conservation and safety. Food irradiation is an economically viable technology both in quality and safety. The purpose of this study was to evaluate carotenoids in Rosa chinensis and Tagete patula flowers submitted to gamma irradiation and electron beam doses of 0.5, 0.8 and 1.0 kGy. High performance liquid chromatography (HPLC) was used to carotenoids determination. The most abundant carotenoids were α-carotene for both species of flowers studied. In general, gamma-irradiated samples presented higher amounts in carotenoids (lutein and alfa-carotene) independently of the applied dose. However, the interaction between irradiation and samples did not affect carotenoids present in edible flowers petals.

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  • IPEN-DOC 26860

    MESQUITA, ANDERSON S. ; ZAHARESCU, TRAIAN; SILVA, LEONARDO G.A. . Efeitos da radiação ionizante no processo de degradação da blenda de DGEBA/EPDM / Electron beam effect on the degradation process of DGEBA/EPDM blend. In: CONGRESSO BRASILEIRO DE POLÍMEROS, 15., 27-31 de outubro, 2019, Bento Gonçalves-RS. Anais... São Carlos, SP: Associação Brasileira de Polímeros, 2019.

    Abstract: A blenda de DGEBA/EPDM pode ser usada para revestir a superfície de outros materiais e protegê-los contra condições térmicas elevadas. O objetivo deste trabalho foi obter, caracterizar e irradiar a blenda de DGEBA/EPDM e estudar os efeitos da radiação ionizante e comparar suas propriedades com uma blenda de DGEBA/EPDM não irradiada. Os compostos possuem 0, 25 e 50% em massa da resina epóxi de DGEBA. O processo de irradiação dos compostos foi feito com doses de 30 e 60 kGy desde um acelerador de elétrons. Posteriormente, estas blendas foram caracterizadas por ensaios de quimiluminescência e espectroscopia de absorção por transformada de Fourier (FTIR). Concluiu-se que as blendas irradiadas de DGEBA/EPDM podem ser usadas em aplicações específicas de acordo com a temperatura de degradação das blendas. Suas propriedades foram satisfatórias para aplicações que necessitem desse tipo de material.

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  • IPEN-DOC 26859

    CHELIGA, PEDRO; MACHADO, ALISSON R.; ROSSI, WAGNER de . Efeito da microtexturização a laser em ferramentas de metal duro na temperatura de corte no torneamento do aço ABNT 1020 / Effect of laser microtexturization on cemented carbide tools in the cutting temperature in turning of ABNT 1020 steel. In: CONGRESO IBEROAMERICANO DE INGENIERÍA MECÁNICA, 14th, November 12-15, 2019, Cartagena de Indias, Colombia. Proceedings... 2019. p. 1-9.

    Abstract: A textura de uma superfície é formada por asperidades e depressões normalmente não ordenadas. Uma superfície organizada e ordenada altera as propriedades e o comportamento tribológico de uma peça ou ferramenta. Dentre as técnicas utilizadas para alterar uma superfície com precisão, se destaca a microtexturização a laser. Trata-se de uma técnica relativamente nova na fabricação de texturas precisas em superfícies quaisquer, podendo ser utilizada para diversas finalidades. Este trabalho tem como objetivo estudar o efeito da microtexturização a laser em ferramentas de corte de metal duro na temperatura da interface cavaco-ferramenta, no torneamento do aço ABNT 1020. Foram desenvolvidas texturas com laser de pulsos ultracurtos (femtosegundos - 10−15 s), numa área de 4 mm x 4 mm na superfície de saída de bits de metal duro, classe P30, com cunha retificada e aresta arredondada previamente. Foram utilizados quatro tipos diferentes de texturas, canais paralelos à aresta principal de corte, canais perpendiculares à aresta principal de corte, canais oblíquos (a 45º) à aresta principal de corte e do tipo “Chevron”. Estas ferramentas foram utilizadas em ensaios individuais para medição da temperatura da interface cavaco ferramenta, pelo método do termopar ferramenta-peça, no torneamento, variando-se a velocidade de corte e o avanço, tanto na condição a seco como usando MQL. Ferramentas sem texturas também foram utilizadas para comparação. Os resultados mostraram que as microtexturas auxiliam na redução da temperatura de corte, em especial para a ferramenta com microtextura paralela a aresta de corte.

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  • IPEN-DOC 26858

    BERGAMASCHI, VITOR; CARNEIRO, MARCELO B.; ROSSI, WAGNER de ; NEVES, MAURICIO D.M. . Tratamento térmico de endurecimento por laser pulsado de Nd:YAG em aço-rápido / Hardening heat treatment by Nd:YAG pulsed laser in high-speed steel. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICAÇÃO, 10., 5-7 de agosto, 2019, São Carlos, SP. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2019.

    Abstract: O uso do laser no processamento de materiais é uma área de pesquisa em ascensão, sendo que o mesmo tem sido utilizado em processos avançados de fabricação e em tratamentos superficiais. Quanto aos tratamentos superficiais, destaca-se o de endurecimento seletivo, que provoca o aumento de dureza da superfície do material da peça, possibilitando a redução do desgaste e aumento no tempo de vida do componente. Nesse sentido, o objetivo do trabalho foi avaliar a influência de alguns parâmetros de aplicação do laser pulsado de Nd:YAG na alteração sub-superficial de uma amostra de aço-rápido sinterizado (HSS/PM). Para tanto, foi realizada a preparação metalográfica da seção transversal da amostra atacada pelo laser, para em seguida realizar as caracterizações por microscopia óptica e eletrônica de varredura, mecânica através do ensaio de microdureza Vickers e física para a identificação das fases formadas através da difração de raios-X (DRX). A análise dos resultados mostrou que os parâmetros do laser influenciaram significativamente na profundidade da alteração sub-superficial, da mesma forma que promoveram variação de dureza, provavelmente, devido a formação de martensita e carbonetos detectadas em DRX.

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  • IPEN-DOC 26857

    ALMEIDA, GUSTAVO S. de; COELHO, REGINALDO T.; CARNEIRO, MARCELO B.; BARBOSA, PATRICIA A.; ROSSI, WAGNER de ; SAMAD, RICARDO E. ; VIEIRA JUNIOR, NILSON D. ; MACHADO, ALISSON R.. Avaliação do desempenho de ferramenta de metal duro texturizada por laser de pulsos ultracurtos / Evaluation of cemented carbide tool texturized by ultrashort laser pulses. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICAÇÃO, 10., 5-7 de agosto, 2019, São Carlos, SP. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2019.

    Abstract: A texturização por laser de pulsos ultracurtos provoca uma ablação com mínimo dano térmico, preservando as características adjacentes do material ablacionado. Deste modo, torna-se possível gerar microtexturas na superfície de saída da ferramenta de usinagem, buscando melhoria de desempenho. Este trabalho realiza uma comparação entre duas ferramentas de corte de metal-duro, TPUN 160304, sendo uma texturizada e a outra de referência (nãotexturizada), durante o torneamento de um aço inoxidável austenítico (V304UF). Para isto, os parâmetros de corte foram mantidos constantes. Avaliou-se a força de usinagem, o desgaste de flanco da ferramenta, além da rugosidade produzida sobre a peça. Os resultados mostraram um melhor comportamento para ferramenta texturizada.

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  • IPEN-DOC 26855

    GIOVEDI, C.; MARTINS, M.R.; ABE, A. ; REIS, R. ; SILVA, A.T. . Reactivity initiated accident assessment for ATF cladding materials. In: TECHNICAL MEETING ON MODELLING OF FUEL BEHAVIOUR IN DESIGN BASIS ACCIDENTS AND DESIGN EXTENSION CONDITIONS, May 13-16, 2019, Shenzhen, China. Proceedings... 2019.

    Abstract: Following the experience that came from the Fukushima Daiichi accident, one possible way of reducing risk in a nuclear power plant operation would be the replacement of the existing fuel rod cladding material (based on zirconium alloys) by another materials which could fulfill the requirements of the accident tolerant fuel (ATF) concept. In this sense, ATF should be able to keep the current fuel system performance under normal operation conditions; moreover, it should present superior performance than the existing conventional fuel system (zirconium-based alloys and uranium dioxide) under accident conditions. The most challenging and bounding accident scenarios for nuclear fuel systems in Pressurized Water Reactors (PWR) are Loss of Coolant Accident (LOCA) and Reactivity Initiated Accident (RIA), which are postulated accidents. This work addresses the performance of ATF using iron-based alloys as cladding material under RIA conditions. The evaluation is carried out using modified versions of the coupled system FRAPCON/FRAPTRAN. These codes were modified to include the material properties (thermal, mechanical, and physics) of an iron-based alloy, specifically FeCrAl alloy. The analysis is performed using data available in the open literature related to experiments using conventional PWR fuel system (zirconium-based alloys and uranium dioxide). The results obtained using the modified code versions are compared to those of the actual existing fuel system based on zircaloy-4 cladding using the original versions of the fuel performance codes (FRAPCON/FRAPTRAN).

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  • IPEN-DOC 26854

    GOMES, D.S. ; ABE, A. ; SILVA, A.T. ; MUNIZ, R.O.R. ; GIOVEDI, C.; MARTINS, M.R.. Assessment of high conductivity ceramic fuel concept under normal and accident conditions. In: TECHNICAL MEETING ON MODELLING OF FUEL BEHAVIOUR IN DESIGN BASIS ACCIDENTS AND DESIGN EXTENSION CONDITIONS, May 13-16, 2019, Shenzhen, China. Proceedings... 2019.

    Abstract: After the Fukushima Daiichi accident, the high conductivity ceramic concept fuel has been revisited. The thermal conductivity of uranium dioxide used as nuclear fuel is relatively low, as consequence fuel pellet centerline reaches high temperatures, high fission gas release rate, increase of fuel rod internal pressure reducing the safety thermal margin. Several investigations had been conducted in framework of ATF (Accident Tolerant Fuel) using different additives in ceramic fuel (UO2) in order to enhance thermal conductivity in uranium dioxide pellets. The increase of the thermal conductivity of fuel can reduce the pellet centerline temperature, consequently less fission gas releasing rate and the low risk of fuel melting, hence improving significantly fuel performance under accident conditions. The beryllium oxide (BeO) has high conductivity among other ceramics and is quite compatible with UO2up to 2200°C, at which temperature it forms a eutectic. Moreover, it is compatible with zircaloy cladding, does not react with water, has a good neutronic characteristics (low neutron absorption cross-section, neutron moderation). This work presents a preliminary assessment of high conductivity ceramic concept fuel considering UO2-BeO mixed oxide fuel containing 10 wt% of BeO. The FRAPCON and FRAPTRAN fuel performance codes were conveniently adapted to support the evaluation of UO2-BeO mixed oxide fuel. The thermal and mechanical properties were modified in the codes for a proper and representative simulation of the fuel performance. Theobtainedpreliminary results show lower fuel centerline temperatureswhen compared to standard UO2 fuel, consequently promoting enhancement of safety margins during the operational condition and under LOCA accident scenario.

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  • IPEN-DOC 26853

    TERAM, ROGERIO; SANTOS, GIVANILDO A. dos; NASCIMENTO, MAURICIO S.; COUTO, ANTONIO A. ; SANTOS, VINICIUS T. dos; SILVA, MARCIO R. da. Influência do espaçamento dendrítico secundário na dureza da liga Cu-14Al-5Ni-5Fe obtida por solidificação unidirecional / Influence of the secondary dendritic spacing on the hardness of the Cu-14Al-5Ni-5Fe alloy obtained by unidirectional solidification. In: CONGRESO IBEROAMERICANO DE INGENIERÍA MECÁNICA, 14th, November 12-15, 2019, Cartagena de Indias, Colombia. Proceedings... 2019. p. 1-6.

    Abstract: O objetivo deste trabalho é analisar a influência do espaçamento dendrítico secundário, na dureza da liga Cu-14Al- 5Ni-5Fe após a realização de processo de solidificação. A liga foi solidificada em um dispositivo de solidificação direcional ascendente sendo o calor extraído através de refrigeração à água em uma base de aço SAE 1020. As medições dos espaçamentos dendríticos secundários foram obtidas por meio de microscopia óptica e software acoplado. As variáveis térmicas de solidificação como velocidade de deslocamento da isoterma liquidus (VL) e taxa de resfriamento (TR) foram avaliadas em função da distância da superfície de extração de calor. A dureza e os espaçamentos dendríticos secundários foram correlacionados com as posições de termopares devidamente dispostos no lingote. Em função dos resultados obtidos, conclui-se que maiores taxas de resfriamento apresentam espaçamentos dendríticos secundários mais refinados que propiciam maiores valores de dureza.

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  • IPEN-DOC 26823

    MACHADO, CARULINE de S.C. ; SILVA, REJANE M. da ; ARAUJO, JOAO V. de S. ; DONATUS, UYIME ; MILAGRE, MARIANA X. ; KLUMPP, RAFAEL E. ; ROSSI, JESUALDO L. ; COSTA, ISOLDA . Effects of chloride ion concentration on the corrosion behavior of the AA2198-T8 alloy. In: EUROPEAN CORROSION CONGRESS, September 9-13, 2019, Seville, Spain. Proceedings... 2019.

    Abstract: In this work, the influence of chloride ions concentration on the corrosion behavior of the AA2198-T8 alloy was evaluated. Immersion test and electrochemical analyses were performed in sodium chloride solutions of three concentrations, 0.001 mol L-1, 0.005 mol L-1 and 0.01 mol L-1. The results showed that the AA2198-T8 alloy was susceptible to localized corrosion (LC) and to severe localized corrosion (SLC) in all conditions investigated. The electrochemical results obtained by open circuit potential measurements, cyclic voltammetry and potentiodynamic polarization curves were associated with the corroded microstructure of the alloy. Although electrochemical techniques allowed differentiating the corrosion resistance as a function of chloride concentration, the result was strongly influenced by the corroded/uncorroded area ratio related to the SLC.

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  • IPEN-DOC 26801

    SANTANA, TATIANA D.; ROSSI, WAGNER de ; BARBOSA, PATRICIA A.; CARNEIRO, MARCELO B.. Caracterização por microscopia óptica 3D de ferramenta de corte texturizada por laser de femtossegundos. In: COLÓQUIO DE USINAGEM, 23., 12-13 de dezembro, 2019, Uberlândia, MG. Anais... Uberlândia, MG: Universidade Federal de Uberlândia, 2019.

    Abstract: As superfícies possuem características que podem impactar no coeficiente de atrito, na adesão de filmes e células, na retenção de fluidos lubrificantes, em aspectos ópticos, químicos e mecânicos. Dessa forma, muitos parâmetros foram criados com intuito de caracterizar as superfícies após um determinado processo de manufatura. Em geral, os equipamentos utilizados para realizar tal tarefa são categorizados em com e sem contato com as superfícies em avaliação. Nos processos de usinagem convencional, condições severas de atrito na interface cavaco ferramenta aumentam o desgaste da ferramenta e reduz o seu tempo de vida. A habilidade do fluido de corte penetrar na zona de corte pode ser melhorada pela texturização da superfície de saída da ferramenta. Neste trabalho, uma ferramenta de corte foi texturizada com o uso de um laser de femtossegundos, e caracterizada com o uso de um microscópio óptico 3D com tecnologia confocal que garante medições precisas da topografia, sem contato.

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  • IPEN-DOC 26540

    ARAUJO, LEANDRO G. de ; WATANABE, NAOMI ; SILVA, THALITA T.; TEIXEIRA, ANTONIO C.S.C.; VELOSA, ADRIANA C. de; MARUMO, JULIO T. . Oxidative degradation of organic compounds from sludge by ozonation: study of process. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 45th, March 3-7, 2019, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2019. p. 1-6.

    Abstract: This study investigates the performance of the ozonation process in the treatment of petroleum sludge from an offshore production platform situated in Brazil. The effect of operating conditions is studied such as the phase to be treated and the sludge/water ratio. Total organic carbon content increased in O2 and O3 experiments, mainly because of the mixing factor. The decrease of sludge mass was observed in a situation of forced mixing and with only ozone flow. The liquid phase indicated a high TOC value, but very low radioactive activities, whereas the solid phase did not present detectable TOC amounts but significant values of radioactive activity. More experiments and analyzes will be carried out to obtain more relevant results for future discussion.

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  • IPEN-DOC 26791

    BEU, CASSIA M.L. ; LANDULFO, EDUARDO . Threshold wind speed and turbulence under LLJs events at Ipero - Brazil. In: COMERON, ADOLFO (Ed.); KASSIANOV, EVGUENI I. (Ed.); SCHAFER, KLAUS (Ed.); PICARD, RICHARD H. (Ed.); WEBER, KONRADIN (Ed.); SINGH, UPENDRA N. (Ed.) SPIE REMOTE SENSING, September 9-12, 2019, Strasbourg, France. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 1115212-1 - 1115212-10. (Proceedings of SPIE Vol. 11152, Remote Sensing of Clouds and the Atmosphere XXIV). DOI: 10.1117/12.2532281

    Abstract: The threshold wind speed is a useful criterion in determining whether strong turbulence is generated within the Stable Boundary Layer (SBL), the layer where all surface emissions remain con ned during the night. Con dence turbulence estimates are extremely important for atmospheric transport and dispersion simulations, although due to its complex dinamics many aspects of the SBL are neglected by numerical models that, in turn, are the inputs and boundary conditions for the transport and dispersion simulations. Turbulence is especially important during severe episodies like hazardous material accidental releases, for example. Turbulence intensity can a ect the dispersion speed, released material concentration, and its reach. For many decades, remote sensing has been an important tool in lling the gap of information and providing advances in the atmospheric sciences. The doppler lidar is increasingly being used for micrometeoroly and Planetary Boundary Layer (PBL) studies because of its autonomy and long range capability, in contrast with traditional techniques as radioprobes and captive balloons. After 1 year of continuous measurements with a doppler lidar, it was possible to determine the threshold wind speed for Ipero, Sao Paulo, Brazil. Besides threshold wind speed, it was observed that the SBL turbulence has a straight relationship with the Low-Level Jets (LLJs) that frequently occur over the region. The vertical turbulence distribution depends greatly on the LLJ characteristics, which in turn is highly variable during its life cycle. The strong turbulence regime is associated to the stronger LLJs, that presents a more de ned pattern. In contrast, weak LLJs (that generate weaker SBL turbulence) present more dispersive characteristics in respect to the entire dataset. These di erences are seen both for the LLJ height as for the turbulence vertical pro le. These results will contribute for the atmospheric modeling and dispersion simulations, as well for the environmental studies at Ipero.

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  • IPEN-DOC 26790

    MACEDO, FERNANDA M.; CORREA, THAIS ; ARAUJO, ELAINE ; ANDRADE, IZABEL ; ARLEQUES, ANTONIO G. ; MIRANDA, JULIANA T. de M. ; SILVA, JONATAN da ; GUARDANI, ROBERTO; VESELOVSKII, IGOR; LANDULFO, EDUARDO . Correlation between two different real time data acquisition systems: LIDAR Raman and Cavity Ringdown Laser Spectroscopy, for CH4 as a fugitive gas, in São Paulo Metropolitan Area. In: COMERON, ADOLFO (Ed.); KASSIANOV, EVGUENI I. (Ed.); SCHAFER, KLAUS (Ed.); PICARD, RICHARD H. (Ed.); WEBER, KONRADIN (Ed.); SINGH, UPENDRA N. (Ed.) SPIE REMOTE SENSING, September 9-12, 2019, Strasbourg, France. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 111521D-1 - 111521D-14. (Proceedings of SPIE Vol. 11152, Remote Sensing of Clouds and the Atmosphere XXIV). DOI: 10.1117/12.2533111

    Abstract: Fugitive emissions, defined as unintended or irregular leaks of gases and vapors, these are an important source of pollutants to the atmosphere, which is difficult to monitor and control. These sources are present in different sites, including megacities like São Paulo that are growing in size and economic activity. At the same time, there is a remarkable growth in concerns about the environmental issues associated with these activities. In a constantly changing world, with increasing concentrations of greenhouse gases (GHGs), among them methane (CH4) and volatile organic compounds (VOC), mitigation of atmospheric emission of these gases to contain global warming, make field campaigns in the metropolitan region of São Paulo very relevant. Optical remote sensing techniques as lidar can attend the need for real time and trustable information on fugitive emissions. The Cavity Ringdown Laser Spectroscopy (CRDS) technique was adopted because it is widely used in the detection of gas samples that absorb light at specific wavelengths and also for their ability to detect mole fractions up to the parts per trillion level. The Raman lidar system used includes a commercial laser pulsed Nd:YAG Quantel S.A., model CFR 200, with wavelengths of 355 nm, 353 nm and 396 nm, 120 mJ pulse power, with laser repetition rate of 20 Hz and pulse width of 20 s, with a spatial resolution of 7,5 m. The system includes an ethernet interface, used together with LabView software to control the measurement and readout of the acquired data. The mixing ratio of CH4 can be observed within the planetary boundary layer. The measured methane profiles correlate with the acquisitions made with the CRDS, however, an additional contribution of control data in which the Raman lines detect with high sensitivity.

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  • IPEN-DOC 26789

    GEORGESCU, GABRIEL; NUNES, MARCOS E.C.; OLIVEIRA, PATRICIA da S.P. de ; WIELENBERG, ANDREAS; NIEMELA, ILKKA; DUPUY, PATRICIA. RISKAUDIT and CNEN cooperation on probabilistic safety analysis. In: INTERNATIONAL TOPICAL MEETING ON PROBABILISTIC SAFETY ASSESSMENT AND ANALYSIS, 16th, April 28 - May 3, 2019, Charleston, South Carolina, USA. Proceedings... Illinois, USA: American Nuclear Society, 2019. p. 781-784.

    Abstract: The Brazilian project BR3.01/12 financed by European Union through the “Instrument for Nuclear Safety Cooperation” (INSC) programme and accomplished by RISKAUDIT organization (IRSN, GRS and STUK) constituted a support for enhancing and strengthening Brazilian Safety Authority (CNEN) expertise in regulatory and licensing activities, including probabilistic safety analysis (PSA), deterministic analysis and ageing management. The objectives of the project PSA task were to provide support to CNEN on the enhancement of its regulatory capability related to PSA development, review and applications and to provide support to CNEN on the review of the documents related to parts of Level 1 and 2 PSAs submitted by the utility, Eletronuclear (ETN), for the Brazilian NPPs of the CNAAA, which is a nuclear station located in Angra dos Reis, Rio de Janeiro. The activities focused on the updating and enhancement of Brazilian regulatory requirements for development and use of PSA, development of the Brazilian guide on regulatory review of PSA, support CNEN on the preliminary review of the PSAs for Angra 2 NPP, support CNEN on the management of Level 1 PSA computer codes and training CNEN staff on PSA methods, PSA review and PSA applications. The project, which started in May 2015, successfully ended in May 2018.

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  • IPEN-DOC 26788

    SILVA, N.F. ; SILVA, T.F.; CASTRO, M.C. ; LUZ, H.N. da; CALDAS, LINDA V.E. . Garfield++ simulation of a TH-GEM based detector for standard mammography beam dosimetry. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: The TH-GEM based detector is a robust, simple to manufacture, high-gain gaseous electron multiplier. Its operation is based on a standard printed circuit board (PCB) coated on both sides by metallic material, perforated in a millimeter pattern, and immersed in gas. In order to study the feasibility of using TH-GEM type detectors in dosimetric applications for standard mammography beams, a prototype with adequate dimensions and materials was produced. The present work encompasses the calculations of electric fields by the Gmsh and Elmer software packages and the avalanche simulation using Garfield++ library of a TH-GEM detector filled with Ar/CO2 (70:30) mixture at atmospheric pressure.

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  • IPEN-DOC 26787

    POLO, IVON O. ; CALDAS, LINDA V.E. . Fading estimation of SOL-GEL α-Al2O3 detectors. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: The OSL and the TL techniques are used in several fields of radiation dosimetry. The dosimeters are affected by a signal loss in the time between the irradiation and readout (fading). This undesirable characteristic can cause an underestimation of the irradiation dose. The fading estimation of SOL-GEL α-Al2O3 with several different concentrations of impurities is reported. The thermal fading and the light-induced fading of the SOL-GEL α-Al2O3 detectors were estimated. Furthermore, the exponential equations used to interpolate the experimental results were presented.

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  • IPEN-DOC 26786

    SANTOS, WILLIAM S. ; SANTOS, CARLA J.; SILVA, ALINE F. da; SOUZA, SAMARA P.; NEVES, LUCIO P.; BELINATO, WALMIR; CALDAS, LINDA V.E. ; PERINI, ANA P.. Dose evaluation in breast brachytherapy using different 125I seeds: a Monte Carlo approach. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: A very common type of cancer among women is the breast cancer. The treatment choice depends, among several factors, on the clinical stage of the disease and the age. One way to treat breast cancer is the permanent breast seed implant, with Iodine-125 (125I). Since they present some advantages: possibility to treat solid tumors, near the tumor site, induction of little trauma and strong lethality to cancer cells. In Brazil, a new 125I seed was developed at the Instituto de Pesquisas Energéticas e Nucleares to be applied in brachytherapy. Given the large number of women diagnosed with breast cancer, in this work, the dose determination in organs and tissues was undertaken, considering this new seed and a commercial, Amersham 6711-Oncoseed®, employing the Monte Carlo method. Moreover, for a better understanding of the radiation doses delivered to different patients, the breast volumes were modified. For this purpose, the MCNPX Monte Carlo code was utilized coupled with female virtual anthropomorphic phantoms. The results pointed out the highest dose values for the breast and skin. Furthermore, the dose results for both types of seeds were very similar.

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  • IPEN-DOC 26785

    SANTOS, WILLIAM S. ; NEVES, LUCIO P.; PERINI, ANA P.; SANTOS, CARLA J.; BELINATO, WALMIR; SILVA, ROGERIO M.V.; SOARES, MARIA R.; VALERIANO, CAIO C.; CALDAS, LINDA V.E. . Computational modelling of cervix uterus radiation procedure using a virtual anthropomorphic phantom and the MCNPX code. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: There is a serious, and growing, concern about the increased risk of the emergence of a secondary cancer, radio-induced, associated with radiotherapy treatments. To assess the radiation doses to organs outside the target volume, in this work, several computational exposure scenarios were modelled, based on Monte Carlo simulation (MCNPX code). A Varian 2100c accelerator, and a female virtual anthropomorphic phantom were used, in a simulated treatment of cervical cancer. The determination of the dispersed dose would be important for assessing the risk in different organs or tissues. Four treatment fields were applied, varying the gantry angle. It was possible to observe that the conversion factors for equivalent dose were higher for the AP projection. For the RLAT and LLAT projections, the results were similar, fact that may be attributed to the symmetrical distributions of the organs in relation to the radiation source. The results presented in this work showed that the computational exposure scenario provides a versatile and accurate tool to estimate in a ready way the absorbed doses during a cervical treatment.

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  • IPEN-DOC 26784

    LITVAC, DANIEL ; CALDAS, LINDA V.E. . Calibration of a clinical beta therapy applicator using the thermoluminescence samples: preliminary results. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: In some parts of Brazil, 90Sr/90Y clinical applicators are still used for dermatological and ophthalmic treatments, even with the higher efficiency of linear accelerators because they are of lower cost and easier use. Calibration and periodic recalibration of these applicators to verify the absorbed dose rate is essential to ensure accuracy in clinical treatments. In this work the thermoluminescent response of BeO and μLiF pellets was evaluated, determining the reproducibility, linearity of response and their dose-response curves. This standard, for this type of calibration, recommends the use of small detectors such as μLiF. Therefore, the utility of μLiF and BeO in the calibration of clinical applicators was compared.

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  • IPEN-DOC 26783

    SANTOS, ADIMIR dos ; YAMAGUCHI, MITSUO ; FANARO, LEDA C.C.B. ; SANTOS, DIOGO F. dos ; SOUZA, GREGORIO S. de ; JUNQUEIRA, FERNANDO de C. ; SILVA, GRACIETE S. de A. e ; BELCHIOR JUNIOR, ANTONIO ; PRADO, ADELK de C. ; JOAO, THIAGO G.; ROSSI, PEDRO C.R.. New plate-type core of the IPEN/MB-01 research reactor facility for validation of RMB project. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS, November 25-29, 2019, Buenos Aires, Argentina. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2019. p. 1-8.

    Abstract: The IPEN/MB-01 research reactor had its first criticality in November 1988 and, ever since, has been of major importance in Brazilian reactor physics researches, achieving international level for experiments comparison and validation (benchmarks). In this facility it is possible to build many different core configurations (i.e., rectangular, square and cylindrical), once versatility and flexibility were both taken into account on its initial project. The core is a fissile material assembly, inserted in a water tank, where the chain reaction is self-maintained and controlled at low power levels, so that, in normal operation, the feedback effects of temperatures are negligible. The core is intended for neutrons simulation of light water moderated reactors allowing the experimental verification of the calculation methods, reactor cell and mesh structures, control rods effectiveness, isothermal reactivity coefficients and core dynamics due to reactivity insertions. The first standard IPEN/MB-01 core had UO2 rod-type fuel, 4.3 % enriched in U-235 and using B4C and Ag-In-Cd rods for safety and control of the reactor. The facility is located at IPEN/CNEN-SP (Nuclear and Energy Research Institute), in Sao Paulo - Brazil. Within the scope of the new research reactor project, the Brazilian Multipurpose Reactor (RMB), it was designed a new critical configuration for the IPEN/MB-01. After thirty years of work, the rod-type fuels were replaced by plate-type fuels, in order to validate the RMB calculation methodologies, as well as the nuclear data libraries used. The RMB is an open pool-type reactor with maximum power of 30 MW, being the core a 5x5 configuration, consisting of 23 fuel elements, made of U3Si2-Al, having a medium density of 3.7 gU/cm3 and 19.75% enriched in U-235, and two positions available in the core for materials irradiation devices. The production of radioisotopes, silicon doping, neutron activation analysis, nuclear fuels and structural materials testing and the development of scientific and technological research using neutron beams are the main targets of the RMB enterprise. The new IPEN/MB-01 core has a 4×5 configuration, having 19 fuel elements, consisting of U3Si2-Al, 2.8 gU/cm³ and 19.75% enriched in U-235, plus one aluminum block. The IPEN/MB-01 new plate-type fuel assembly uses Cadmium wires as burnable poison, as the one used in RMB core for controlling the core power density and excess of reactivity during its operation. The core is also reflected by 4 boxes of heavy water (D2O), inserted in a moderator tank of light water. The maximum nominal power is 100 W and, for a safe operation, the critical assembly has both safety and auxiliaries’ systems. This paper presents a description of the new core and the principal neutronic parameters. The new core of the IPEN/MB-01 will be certainly a world class benchmark core for the core physics calculation of research reactors.

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  • IPEN-DOC 26782

    FUNGARO, D.A. ; ROVANI, S. . Extração de sílica a partir das cinzas de resíduo da cana-de-açúcar em diferentes condições de extração alcalina. In: BALDOVI, ALDREW A. (Ed.); CONCEIÇÃO, ANA C.S. (Ed.); ANTENOR, ANANDA de O.G. (Ed.); CHYOSHI, BRUNA (Ed.); COSTA, DANILO O. da (Ed.); ANDRADE, HEDLLA M. (Ed.); FARIA, JULIA K. (Ed.); KOHATSU, MARCIO Y. (Ed.); MENDES, MARIANA E. (Ed.); COELHO, LUCIA, H.G. (Coord.); TAMBOSI, LEANDRO R. (Coord.) SIMPÓSIO DE CIÊNCIA E TECNOLOGIA AMBIENTAL, 1st, 2-3 de outubro, 2019, Santo André, SP. Anais... Santo André, SP: Universidade Federal do ABC, 2019. p. 239-244.

    Abstract: Uma amostra de cinzas geradas durante a queima de resíduos de cana-de-açúcar foi triturada com NaOH sólido variando-se a relação cinzas: NaOH (m/m). As misturas foram submetidas ao processo de fusão a 450 oC por 1 h. Após o resfriamento, a sílica da massa fundida foi lixiviada para a fase líquida na forma de silicato de sódio. Seguindo a separação do sólido e do líquido, partículas de sílica foram precipitadas pela adição de ácido sulfúrico até pH 7 à solução de silicato de sódio. O rendimento das amostras mostrou-se constante e uma pureza de 89% foi alcançada. As amostras de cinzas e de sílica produzidas foram caracterizadas por difração de raios-X, fluorescência de raios-X e análise elementar.

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  • IPEN-DOC 26781

    URBANI, G.L.; FRANCO, M.K.K.D. ; YOKAICHIYA, F. ; VICENTE, R. . Aplicação da química de radiação à questões tecnológicas do cimento relacionadas ao desenvolvimento de repositórios de rejeitos radioativos do modelo borehole. In: BALDOVI, ALDREW A. (Ed.); CONCEIÇÃO, ANA C.S. (Ed.); ANTENOR, ANANDA de O.G. (Ed.); CHYOSHI, BRUNA (Ed.); COSTA, DANILO O. da (Ed.); ANDRADE, HEDLLA M. (Ed.); FARIA, JULIA K. (Ed.); KOHATSU, MARCIO Y. (Ed.); MENDES, MARIANA E. (Ed.); COELHO, LUCIA, H.G. (Coord.); TAMBOSI, LEANDRO R. (Coord.) SIMPÓSIO DE CIÊNCIA E TECNOLOGIA AMBIENTAL, 1st, 2-3 de outubro, 2019, Santo André, SP. Anais... Santo André, SP: Universidade Federal do ABC, 2019. p. 226-231.

    Abstract: Resíduos radioativos são usualmente descartados em repositórios do tipo borehole ou de superfície. Por questões de segurança, devem ser depositados em tambores e cobertos por cimento na sua destinação final. A radiação gama proveniente dos resíduos radioativos interage com a água livre da pasta de cimento e causa o fenômeno da radiólise. Essa interação que decompõe a água da pasta de cimento é estudada pela academia científica e ainda não é um consenso se a mesma afeta a resistência do concreto ou não. Para um melhor entendimento dessa questão, nesse estudo um modelo teórico simples é sugerido para quantificar a porcentagem da água que sofre radiólise e se essa perda é suficiente para afetar a resistência da barreira de cimento. O resultado indica que a quantidade de água perdida neste processo não é suficiente para diminuir a resistência do concreto. O modelo proposto foi aplicado para verificar os resultados experimentais, utilizando as condições iniciais expostas na literatura existente, com o propósito comparação e discussão sobre o fenômeno da radiólise.

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  • IPEN-DOC 26770

    GOMES, DANIEL de S. . Study of thoria-urania fuel during accidents. In: INTERNATIONAL CONGRESS OF MECHANICAL ENGINEERING, 25th, October 20-25, 2019, Uberlândia, MG. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2019.

    Abstract: In this investigation, nuclear fuel based on mixed ceramic oxides, using (Th–U)O2 as nuclear fuel and zirconium-based alloy as cladding, was simulated. This strategic configuration can achieve improved safety margins because of an enhanced set of thermal and mechanical properties. The Experimental Breeder Reactor built in the 1950s in Idaho introduced the concept that a reactor can generate more fissile material than it consumes. The thorium fuels have a lower cost and should decrease weapon-grade plutonium compared with conventional fuel, UO2. The nuclear characteristic of thorium-232 or U-238 can make a converter into U-233 or Pu-239. However, using thoria fuels can avoid weapon proliferation by reducing plutonium, and it also should reduce radionuclides such as (Np, Am, Cm). This study uses an optimized composition of Th-75% wt and U-25% wt with an enrichment of 19.5%. We studied the behavior using the fuel licensing codes FRAPCON and FRAPTRAN, including many adaptations for the mixed composition choice. The results prove that thoria–urania fuel has a higher performance than pure uranium dioxide fuel during accidents.

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  • IPEN-DOC 26769

    COSTADELLE, EWERTON L. ; FIGUEIREDO, NEY G.F.; BARRETO, ROGERIO L. ; ALMEIDA, GISELE F.C. ; COUTO, ANTONIO A. . Creep-testing machine retrofit for Ti-6Al-4V alloy study. In: INTERNATIONAL CONGRESS OF MECHANICAL ENGINEERING, 25th, October 20-25, 2019, Uberlândia, MG. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2019.

    Abstract: The Nuclear and Energy Research Institute received two Creep-Testing Machine frame donated from Technological Institute of Aeronautics in nonfunctional mode. These apparatuses has arrived with structure, lever arm and tube furnace. However, they came with no strain gage and no temperature controller. In order to back the machinery to active mode, this work developed a Creep-Testing Machine modernization suite. In fact, this study developed a new PID controller hardware, based in an Arduino open platform. In addition, it used a LVDT developed in Brazil, by Technological Research Institute, to capturing the specimen strain. After the modernization suite implementation, it evaluated the creep strain-rate of the Ti6Al4V alloy at 873 K in 319 MPa. Moreover, compared the results of the same lot material tested in another two ones apparatuses. This open technology was able to maintain the specimen temperature in the set point, getting and saving the test results in a text file and it got results close to the most modern equipment.

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  • IPEN-DOC 26768

    CASTRO, PEDRO A.A. de ; ZEZELL, DENISE M. . Infrared Spectroscopy evaluation of burn wound healing: semi-quantitative study. In: QUINCY BROWN, J. (Ed.); VAN LEEUWEN, TON G. (Ed.) EUROPEAN CONFERENCES ON BIOMEDICAL OPTICS, June 23-27, 2019, Munich, Germany. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 1107304-1 - 1107304-4. (Proceedings of SPIE-OSA Vol. 11073, Clinical and Preclinical Optical Diagnostics II). DOI: 10.1117/12.2527051

    Abstract: Wound healing is a biological response in order to recover the tissue stability after injury. The impaired healing by thirddegree, when the damage achieves the major part of dermis, is defined in four sequential and overlapping phases: Inflammation, transition, proliferative and maturative1. The role of biochemical cascade associated in each phase are still not fully understood, thus systematic evaluations tests are crucial. In fact, the gold standard to interrogate the molecular signature of wound healing is concern on immunohistochemical analysis. This approach tends to be laborious, timeconsuming and require multiple assays2. Since Fourier transform infrared spectroscopy (FTIR) has been demonstrated in other studies to provide molecular change report upon biological samples, the present study aims to estimate the feasibility of FTIR to discriminate healthy and burned skin throughout wound stages.

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  • IPEN-DOC 26767

    LOPES, MONICA S.; MOTA, CLAUDIA C.B.O.; PEREIRA, DAISA L. ; AMARAL, MARCELLO M.; ZEZELL, DENISE M. ; GOMES, ANDERSON S.L.. Effect of Nd:YAG laser and aluminum oxide sandblasting preconditioning on lingual enamel: brackets shear bond strength and morphological characterization. In: WOJTKOWSKI, MACIEJ (Ed.); BOPPART, STEPHEN A. (Ed.); OH, WANG-YUHL (Ed.) EUROPEAN CONFERENCES ON BIOMEDICAL OPTICS, June 23-27, 2019, Munich, Germany. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 1107822-1 - 1107822-3. (Proceedings of SPIE-OSA Vol. 11078, Optical Coherence Imaging Techniques and Imaging in Scattering Media III). DOI: 10.1117/12.2527030

    Abstract: It is known that Nd:YAG laser radiation on dental structure can increase enamel resistance to demineralization; however, few studies report its impact in orthodontics. This study aimed to verify the interaction of Nd:YAG laser and aluminum oxide sandblasting (Al2O3) as preconditioning treatment of lingual brackets bonding to quantify the shear bond strength (SBS) and to characterize the enamel after different surface preconditioning techniques. Thirty-five bovines’ incisors were divided in 5 groups (n=7), according to the preconditioning. All groups had the lingual brackets bonded with Transbond XT adhesive according to manufacturer’ protocol, and shear bonded after 72h. Samples were analyzed by Optical Coherence Tomography (OCT) and Scanning Eletronic Microscope (SEM) to verify enamel alterations. Optical attenuation coefficient (α) was measured before any preconditioning (T0) and after preconditioning surface (T1) for each group. Statistics analysis ANOVA-test was used, followed by Post Hoc Tukey for shear bond strength data, and Kruskal Wallis and post hoc Dunn test for α data. SEM and OCT qualitative analysis showed the melting effect with laser irradiation and enamel crystal surface disorganization with sandblasting in T1 and after shear bond. All groups were adequate for SBS and the statistical differences (p=0.0034) among groups showed better results for groups with techniques association (laser and Al2O3 used in this or in reverse order) and the highest SBS when laser was used after. The Al2O3 removes part of melting effect. The α had statistical difference (p= 0.0124) among groups, increasing with laser and Al2O3 isolated and decrease with techniques association.

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  • IPEN-DOC 26766

    LIMA, CASSIO A. ; CORREA, LUCIANA; BYRNE, HUGH J.; ZEZELL, DENISE M. . Assessing the spectrochemical signatures of skin components using FTIR microspectroscopy. In: QUINCY BROWN, J. (Ed.); VAN LEEUWEN, TON G. (Ed.) EUROPEAN CONFERENCES ON BIOMEDICAL OPTICS, June 23-27, 2019, Munich, Germany. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 110730S-1 - 110730S-3. (Proceedings of SPIE-OSA Vol. 11073, Clinical and Preclinical Optical Diagnostics II). DOI: 10.1117/12.2527137

    Abstract: Fourier Transform Infrared (FTIR) spectroscopy is a label-free analytical technique used to evaluate the chemical profile of a sample based on its molecular vibrations. The potential dermatological applications of FTIR spectroscopy has been well demonstrated over the past decades through many proof-of-concept studies evaluating cancerous and non-cancerous cutaneous diseases. Considering that the correctly identification of skin components plays an important role in the study of cutaneous diseases, the present study aims to evaluate the spectrochemical signatures of dermis and epidermis based on the pixels of a FTIR hyperspectral image collected from healthy skin.

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  • IPEN-DOC 26762

    SIERRA, JULIAN H.; CARVALHO, DANIEL O.; SAMAD, RICARDO E. ; RANGEL, RICARDO C.; ALAYO, MARCO I.. Analysis and measurement of the non-linear refractive index of SiOxNy using pedestal waveguides. In: SYMPOSIUM ON MICROELECTRONICS TECHNOLOGY AND DEVICES, 34th, August 26-30, 2019, São Paulo, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2019. DOI: 10.1109/SBMicro.2019.8919392

    Abstract: In this work, the non-linear refractive index (n2) of silicon oxynitride (SiOxNy) is determined, obtaining a value for this material of n2 = 2.11×10-19 m2/W. The results demonstrate that this material has interesting properties for the development of non-linear optical devices. The paper presents in detail the waveguide fabrication process using the pedestal technique, which allows using different materials since it does not require etching to define the sidewalls of the waveguides. We show the results of the measurement of the n2 employing the non-linear optical phenomena of Self-Phase Modulation (SPM).

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  • IPEN-DOC 26761

    OLIVEIRA, L.S. ; CORREA, O.V. ; BENTO, R.T. ; PILLIS, M.F. . Síntese de alumina anódica nanoporosa em liga de Alumínio AA 1050. In: CONGRESSO BRASILEIRO DE QUÍMICA, 59., 5-8 de novembro, 2019, João Pessoa, PB. Anais... Rio de Janeiro, RJ: Associação Brasileira de Química, 2019.

    Abstract: Nos últimos anos, alumina anódica porosa tem atraído interesse devido ao arranjo regular dos nanoporos, à possibilidade de controle de seu diâmetro, e grande área de superfície específica. Neste trabalho foram obtidas estruturas de alumina anódica porosa por meio da anodização em duas etapas de uma liga de alumínio AA 1050 em eletrólito de H2SO4. As amostras foram anodizadas durante 4 e 8 h. A técnica de microscopia eletrônica de varredura com canhão de emissão de elétrons foi utilizada para a avaliação morfológica da superfície. Os nanoporos formados após 4h de anodização apresentaram distribuição homogênea na superfície da liga e diâmetro médio de 25 nm, enquanto que após 8h de anodização os nanoporos apresentaram-se com formato irregular e distribuição não homogênea.

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  • IPEN-DOC 26760

    BORAZANIAN, T.C.F. ; SZURKALO, M. ; CORREA, O.V. ; BENTO, R.T. ; SANTOS, T.F. ; COTINHO, S.P. ; PILLIS, M.F. . Revestimentos de TiO2 para preservação de superfícies cimentícias. In: CONGRESSO BRASILEIRO DE QUÍMICA, 59., 5-8 de novembro, 2019, João Pessoa, PB. Anais... Rio de Janeiro, RJ: Associação Brasileira de Química, 2019.

    Abstract: Este trabalho tem como objetivo avaliar o desempenho autolimpante de filmes fotocatalíticos de TiO2 aplicados sobre argamassa cimentícia usada como revestimento externo de vedações verticais das edificações. Os filmes foram sintetizados pelo método sol-gel e depositados por spray coating, à temperatura ambiente, sobre substratos de argamassa cimentícia. Foram testadas amostras com uma e duas camadas de deposição de filme e foram realizados testes de autolimpeza. As análises apontam que as amostras com aplicação de duas camadas de filme de TiO2 exibem degradação mais eficiente do corante azul de metileno, após 3 ciclos de 48 horas sob radiação UV, o que sugere sua aplicação promissora para preservação e manutenção de superfícies de revestimentos externos utilizados na construção civil.

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  • IPEN-DOC 26759

    OLIVEIRA, E.C. de ; CORREA, O.V. ; BENTO, R.T. ; COTINHO, S.P. ; SANTOS, T.F. dos ; PILLIS, M.F. . Caracterização morfológica de filmes de TiO2 dopados com nitrogênio crescidos por MOCVD. In: CONGRESSO BRASILEIRO DE QUÍMICA, 59., 5-8 de novembro, 2019, João Pessoa, PB. Anais... Rio de Janeiro, RJ: Associação Brasileira de Química, 2019.

    Abstract: O método de deposição química de organometálicos em fase vapor (MOCVD) foi utilizado para o crescimento de filmes de dióxido de titânio (TiO2) e TiO2 dopado com nitrogênio. Os filmes foram crescidos a 400 °C sobre substratos de vidro borossilicato. Isopropóxido de titânio IV foi utilizado como precursor de titânio e de oxigênio, e amônia (NH3) como fonte de nitrogênio. Análises por microscopia de força atômica (AFM) mostraram que ambos os filmes apresentaram grãos bem definidos e arredondados. Todos os filmes são formados apenas pela fase cristalina anatase. Os resultados mostraram que a dopagem com nitrogênio resultou em uma diminuição no tamanho médio de grão e na rugosidade superficial.

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  • IPEN-DOC 26758

    ROVANI, S. ; CARVALHO, F. ; SANTOS, J.; RAMOS, N.; MORANDI, M.; SALDANHA, M.; FUNGARO, D. . Caracterização físico-química das propriedades de cinzas de cana-de-açúcar de diferentes usinas brasileiras. In: CONGRESSO BRASILEIRO DE QUÍMICA, 59., 5-8 de novembro, 2019, João Pessoa, PB. Anais... Rio de Janeiro, RJ: Associação Brasileira de Química, 2019.

    Abstract: O interesse em transformar biomassa em novas fontes de energia e novos materiais vem fomentando estudos em todo o mundo. As cinzas resultantes da queima de palha e bagaço de cana, por exemplo, é um material rico em sílica. No presente estudo, amostras de cinzas de resíduos de cana-de-açúcar foram coletadas nas usinas de Cerradinho (Chapadão do Céu, GO), Iracema (Iracemápolis, SP) e Guaíra (Guaíra, SP), localizadas em regiões onde os solos são classificados como Latossolos. As cinzas foram caracterizadas pelas técnicas de XRD, EDX, MEV, espectroscopia no IV e DTG. A maioria das amostras de cinzas apresentou sílica como principal constituinte (42-69%) e a sílica na forma cristalina em todas. Diferenças significativas nas concentrações de outros elementos foram observadas.

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  • IPEN-DOC 26757

    BENTO, R.T. ; CORREA, O.V. ; COTINHO, S.P. ; SANTOS, T.F. dos ; PILLIS, M.F. . Avaliação do efeito da morfologia e da espessura de filmes de TiO2 na degradação do corante alaranjado de metila. In: CONGRESSO BRASILEIRO DE QUÍMICA, 59., 5-8 de novembro, 2019, João Pessoa, PB. Anais... Rio de Janeiro, RJ: Associação Brasileira de Química, 2019.

    Abstract: Filmes de TiO2 com diferentes espessuras foram crescidos por MOCVD sobre vidro borossilicato a 400°C. Os efeitos das características morfológicas e da espessura dos filmes sobre sua atividade fotocatalítica foram avaliados a partir da degradação do corante alaranjado de metila sob luz UVA. Os resultados apontaram a existência de um valor ideal de espessura, no qual o catalisador exibe o melhor desempenho fotocatalítico. O filme de TiO2 com espessura de 470 nm exibiu o melhor comportamento, com uma eficiência de 65,3 % em 5 horas de uso. O filme apresentou uma elevada estabilidade fotocatalítica, após diversos ciclos de utilização, o que permite a sua aplicação prática no tratamento de água a partir de um método verde, e com alta durabilidade e eficiência

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  • IPEN-DOC 26756

    PIERETTI, E.; BORAZANIAN, T. ; CORREA, O. ; PILLIS, M. ; ANTUNES, R.. Análise eletroquímica de um biomaterial revestido por TiO2. In: CONGRESSO BRASILEIRO DE QUÍMICA, 59., 5-8 de novembro, 2019, João Pessoa, PB. Anais... Rio de Janeiro, RJ: Associação Brasileira de Química, 2019.

    Abstract: O presente trabalho avaliou, por técnicas eletroquímicas, superfícies do aço inoxidável austenítico ISO 5832-1 recobertas com filmes de TiO2, sintetizados pelo método sol-gel. As técnicas eletroquímicas utilizadas foram: monitoramento de potencial de corrosão em circuito aberto em função do tempo de imersão em solução de Ringer, que simula os fluidos corpóreos; espectroscopia de impedância eletroquímica e cálculo de densidades de dopantes no filme passivo por meio da abordagem de Mott-Schottky. Amostras deste mesmo biomaterial sem recobrimento foram analisadas para fins de comparação. Os resultados indicaram diminuição da susceptibilidade à corrosão localizada nas amostras recobertas por TiO2, devido ao caráter aderente e protetor dos filmes depositados nas superfícies deste biomaterial.

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  • IPEN-DOC 26755

    PEREIRA, DAISA L. ; DEL VALLE, MATHEUS; GOMES, GABRIELA V. ; ZEZELL, DENISE M. ; ANA, PATRICIA A.. Optical properties of bovine dentin when irradiated by Nd:YAG and a black dentifrice aimed at treating dentin erosion. In: COSTA-FELIX, RODRIGO (Ed.); MACHADO, JOÃO C. (Ed.); ALVARENGA, ANDRÉ V. (Ed.) BRAZILIAN CONGRESS ON BIOMEDICAL ENGINEERING, 26th, October 21-25, 2018, Armação de Buzios, RJ. Proceedings... Singapore: Springer Nature Singapore, 2019. p. 847-850. (IFMBE Proceedings 70/2). DOI: 10.1007/978-981-13-2517-5_131

    Abstract: Dental erosion has been extensively studied as a risk factor for tooth loss or injure, and the early diagnosis of lesions is essential for avoiding greater damages. Optical Coherence Tomography (OCT) is a potential tool for early diagnosis of demineralization. In this study, this technique was used to analyze the optical changes of dentin samples irradiated with Nd:YAG laser using a black dentifrice as photoabsorber, then submitted to an erosive cycling. 75 slabs of bovine root dentin were randomized into 5 groups: G1—untreated; G2—treated with acidulated phosphate fluoride gel (APF-gel, [F-] = 1.23%, pH = 3.3–3.9); G3—irradiated with Nd: YAG laser (100 μs, 1064 nm, 0.6 W, 10 Hz) without photoabsorber; G4—irradiated with Nd:YAG laser using a coal paste as photoabsorber; G5—irradiated with Nd: YAG laser using a black dentifrice as photoabsorber. All samples were submitted to a 3-day erosive demineralization (Citric acid 1%, pH = 3.6, 5 min, 2 /day) under agitation, and remineralization (artificial saliva, pH = 7, 120 min) cycling. The samples were evaluated by OCT before treatments (baseline), after treatments and after erosive cycling. Optical attenuation coefficient (μ) was calculated using a Matlab routine, and the statistical analysis was performed (a = 0.05). It was observed a significant decrease on μ values after all treatments. Also, the μ values decreased after erosive cycling, except for the groups G3 and G5. It was concluded that OCT technique is capable to distinguish among sound, treated and demineralized dentin. As well, the black paste was efficient to act as a photoabsorber, helping the Nd:YAG laser to decrease dentin erosion.

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  • IPEN-DOC 26754

    FERREIRA, ELIZABETE dos S.; PRATES, ILKA T.K.; SANTOS JUNIOR, SERGIO L.M. dos; DEL VALLE, MATHEUS; ZEZELL, DENISE M. ; ANA, PATRICIA A.. In vitro study of Er,Cr:YSGG laser effects when used for the prevention of dentin demineralization. In: COSTA-FELIX, RODRIGO (Ed.); MACHADO, JOÃO C. (Ed.); ALVARENGA, ANDRÉ V. (Ed.) BRAZILIAN CONGRESS ON BIOMEDICAL ENGINEERING, 26th, October 21-25, 2018, Armação de Buzios, RJ. Proceedings... Singapore: Springer Nature Singapore, 2019. p. 825-829. (IFMBE Proceedings 70/2). DOI: 10.1007/978-981-13-2517-5_127

    Abstract: Erbium lasers can be used to prevent dental caries, which has a high prevalence in the worldwide population. However, effective irradiation parameters for root dentin have not yet been determined using the Er,Cr:YSGG laser. Objective: this study evaluated the chemical, morphological and optical effects of Er,Cr:YSGG laser on root dentin when aimed at preventing root caries. Methodology: 75 bovine root dentin slabs were randomly distributed in 5 groups: G1-untreated; G2-treated with acidulated phosphate fluoride gel (APF-gel, [F−]= 1.23%); G3-Er,Cr: YSGG laser irradiation (2.78 μm, 60 μs, 6 J/cm2, 8,67 mJ/pulse, 0.25 W); G4-Laser irradiation + APF-gel application; G5-APF-gel application + Laser irradiation. The chemical and morphological evaluations were performed using Fourier transformed infrared spectroscopy and scanning electron microscopy, respectively. Afterwards, the samples were submitted to an 8-day pH-cycling model and the optical attenuation coefficient was evaluated by optical coherence tomography. The statistical analysis was performed considering the level of significance of 5%. Laser irradiation alone does not alter the dentin composition, but the previous application of APF-gel followed by laser irradiation significantly decreased the content of m3m4 carbonate of dentin. This treatment also promoted greater morphological alterations, such as ablation of the surface, when compared to the treatments alone. After demineralization, this treatment also presented the highest optical attenuation coefficient value when compared to the other treatments, indicating less demineralization of the samples. Conclusion: Er,Cr: YSGG laser presents potential for use in prevention of root dentin demineralization, and is more efficient when preceded by the application of APF.

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  • IPEN-DOC 26753

    PANESI, RICARDO ; BERUSKI, OTAVIO ; KORKISCHKO, IVAN ; OLIVEIRA NETO, ALMIR ; SANTIAGO, ELISABETE . Modeling and parametric analysis of PEM fuel cells using computational fluid dynamics. In: INTERNATIONAL CONGRESS OF MECHANICAL ENGINEERING, 25th, October 20-25, 2019, Uberlândia, MG. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2019.

    Abstract: This paper presents a parametric investigation of PEMFC electrochemical models employing computational fluid dynamics (CFD) technique and aims to determine the relative importance of each parameter on the modeling results. A compatible and systematic mathematical model is developed in order to study the effect of these parameters. The model is applied to an isothermal, steady state an single phase to observe the main results by a polarization curve. The results compare well with the experimental polarization data obtained at 80 ºC for ohmic and activation regions. The best match with the experimental data is obtained when the specific active surface area of the catalyst layer is 700 cm2/mg and electrolyte conductivity of 8 S/m.

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  • IPEN-DOC 26557

    GOMES, JOAO P.C. ; SOUZA, KATIA R. de; PEDRIALI-MORAES, CARLA A.; SEO, EMILIA S.M. . Sabonete com base auto-emulsionante polimérica A/O com potencial repelente. In: CONGRESSO LATINO-AMERICANO E IBÉRICO DE QUÍMICOS COSMÉTICOS, 24., 21-23 de maio, 2019, São Paulo, SP. Anais... 2019. p. 1-11.

    Abstract: O uso de repelentes é uma proteção individual, a qual é de extrema importância para evitar os surtos promovidos pela febre amarela, dengue, febre Chikungunya e o vírus Zika. Os repelentes mais eficazes são os tópicos convencionais com ativos sintéticos e naturais. Como alternativa mais efetiva existem os repelentes tópicos convencionais, que podem ser sintéticos ou naturais. Para minimizar os riscos de esquecimento ou do uso incorreto dos repelentes tópicos convencionais (como em forma de creme, gel ou líquido), este trabalho teve a proposta alternativa do desenvolvimento do sabonete com poliamida 3, sendo uma base sabonete com potencial de repelência. Sua vantagem, além da praticidade, é assegurar a proteção do usuário desde o banho formando um filme resistente à água e assim, evitar a não proteção em razão do esquecimento do uso dos cremes ou sprays. O filme formado sobre a pele é oriundo da junção da Polyamide 3 Resin com os emolientes: Propylene Glycol Dicaprylate/ Dicaprate, Isopropyl Myristate, Isostearyl Alcohol e Isostearyl Isostearate. Os ativos Cymbopogon nardus e Ethyl butylacetylaminopropionate promovem a repelência. A base dos sabonetes moldado e gel cremoso foi mais estável quando a poliamida é submetida a alta temperatura para a incorporação dos emolientes a sua estrutura. Os ativos estudados tiveram melhor eficácia quando o sabonete esteve com o pH na faixa 5,5 à 6,3. As formulações base e com o ativo óleo essencial de citronela apresentaram mínima alteração no pH.

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  • IPEN-DOC 26549

    BAPTISTA, A.; NUNEZ, S.C.; MARTIN, A.A.; RIBEIRO, M.S. . Targets of photodyamic inactivation in fungal cells. In: HASAN, TAYYABA (Ed.) INTERNATIONAL PHOTODYNAMIC ASSOCIATION WORLD CONGRESS, 17th, June 28 - July 4, 2019, Cambridge, Massachusetts, USA. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 11070BY-1 - 11070BY-6. (Proceedings SPIE 11070). DOI: 10.1117/12.2537128

    Abstract: Photodynamic inactivation (PDI) has been reported to be effective to eradicate a wide variety of pathogens, including antimicrobial-resistant microorganisms. However, there are conflicting reports in the literature about the effect of growth phase on the susceptibility to PDI. The aim of this study was to identify the potential molecular targets of PDI on Candida albicans in exponential growth phase after PDI mediated by methylene blue (50μM) and exposure to a 660nm-LED (P=360mW). For this task, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) techniques were employed. Pre-irradiation time was set at 10min and exposure time was 15 min delivering a radiant exposure of 162 J/cm2 on a 24-well plate of about 2 cm2. Morphological analysis revealed cell damage after PDI. FT-IR predominantly showed degradation of functional groups related to C-O of deoxyribose; C-C of DNA; C-O stretching vibration of C-OH group of ribose-RNA; P-O stretching modes from the phosphodiester groups of nucleic acids; C=C, C=N, C=O, N=H proteins and amides. Previous studies from our group had demonstrated different targets on the same cells but in stationary growth phase. Therefore, we can conclude that PDI promoted damage to intracellular structures in fungal cells at exponential-phase growth and information on the susceptibility of different growth phases to PDI can be of great importance for the development of treatment strategies that would lead to inactivation of fungal cells in all possible phases of growth in a way that would turn the clinical PDI treatment effective and predictable.

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  • IPEN-DOC 26536

    RIBEIRO, MARTHA S. ; SABINO, CAETANO P.; NUNEZ, SILVIA C.. Antimicrobial photodynamic therapy: from basis to clinical applications. In: HASAN, TAYYABA (Ed.) INTERNATIONAL PHOTODYNAMIC ASSOCIATION WORLD CONGRESS, 17th, June 28 - July 4, 2019, Cambridge, Massachusetts, USA. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 1107048-1 - 1107048-9. (Proceedings SPIE 11070). DOI: 10.1117/12.2527918

    Abstract: Antimicrobial photodynamic therapy (APDT) combines the use of light with a photosensitizer (PS) and oxygen to kill microbial cells. Even though this technique was first reported in the beginning of the 20th century, APDT never took off as antimicrobial chemotherapy did. However, microbial resistance to chemotherapy is currently expanding in faster rates than drug discovery. Therefore, introduction of therapeutic alternatives that bypass mechanisms of drug resistance now presents an urgent status. Fortunately, the scientific and technological development related to APDT made it far more feasible for mainstream clinical applications. Our research group has been working on mechanisms and applications of APDT for almost 20 years. We have already reported that successful APDT results depend on a number of factors, such as PS and light parameters, cell type, and oxygen abundance, among others. We have also demonstrated that APDT is an effective adjuvant in endodontics and periodontics and can be a non-invasive treatment for caries, candidiasis and cutaneous leishmaniasis. In Veterinary Medicine, we have reported effective treatment for penguin pododermatitis, snake stomatitis and dog otitis. This presentation will give an integrated perspective from the basic APDT mechanisms, preclinical and clinical trials to protocol optimization and future perspectives.

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  • IPEN-DOC 26752

    ARQUINTO, JULIANA; SILVA, LEONARDO G. de A. e ; ESPER, FABIO J.; ZACHARIAS, JANICE M.; FILHO, MARCOS M.O.. Produção de bioplastico utilizando amido da semente de jaca (Artocarpus heterophyllus Lam) / Bioplastic production using jackfruit seed starch (Artocarpus heterophyllus Lam). In: CONGRESSO BRASILEIRO DE POLÍMEROS, 15., 27-31 de outubro, 2019, Bento Gonçalves-RS. Anais... São Carlos, SP: Associação Brasileira de Polímeros, 2019. p. 1627-1632.

    Abstract: A intensão deste projeto é apresentar um estudo sobre a influência da palha de milho na propriedade de resistência a tração até ruptura de formulações de bioplástico tendo como base o amido extraído da semente da jaca juntamente com a utilização da glicerina e da trietaloamina como agentes plastificantes. Este bioplástico é um material que em relação ao plástico oriundo dos derivados de petróleo, denota um menor grau de impacto ao meio ambiente após seu descarte. Para isto, o trabalho consistiu inicialmente da extração do amido da semente, com posterior caracterização por FTIR e análise quantitativa do teor de amido no produto extraído. A etapa posterior consistiu da produção das amostras de bioplástico utilizando os agentes plastificantes em uma concentração fixa e variando-se a quantidade de palha de milho na formulação. Por fim, as amostras de bioplástico obtidas foram submetidas ao teste de tração até ruptura para análise de resistência do filme.

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  • IPEN-DOC 26749

    VILLANI, D. ; RODRIGUES JUNIOR, O. ; CAMPOS, L.L. . Study on electronic equilibrium of 137Cs gamma radiation for 3D printed phantoms using OSL dosimetry. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: With the popularization of 3D printing technologies, it is now possible to develop patient specific simulators and various other accessories using this technology in medical physics and dosimetry. This work aims to evaluate the electronic equilibrium of 3D printed phantoms using PLA and ABS filaments compared to PMMA for 137Cs gamma rays using OSL dosimetry. A Landauer microStar ii commercial OSL system were commissioned and it was used nanoDot dosimeters. Phantom plates with 2.5, 3.0 and 5.0 mm thickness were used to obtain electronic equilibrium for 137Cs gamma rays. Measurements were compared with PMMA measurements at standard conditions. Results show that measurements with ABS and PLA thicknesses of 2.5 and 3.0 mm presents dosimetry results within irradiation uncertainty. More accuracy is obtained using 3.0 mm for both PLA and ABS phantoms, with differences in less than 0.5%. It can be concluded that PLA and ABS 3D phantom plates has similar properties of PMMA for 137Cs gamma rays dosimetry and can be used for developing dosimetry accessories for this energy photon beam.

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  • IPEN-DOC 26748

    ASSEMANY, L.P.F. ; RODRIGUES JUNIOR, O. ; POTIENS, M.P.A. . Reuse of 3D printed materials for dosimetry purposes. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: 3D printing technology has been a great ally of the medical industry due to it allows the obtaining of anatomical structures such as custom prostheses, implants and surgery planning simulators for the most several applications. There are in the market, several types of filaments used for 3D printing, being the most used thermoplastics Acrylonitrile Butadiene Styrene (ABS) and Polylactic Acid (PLA). Within the modeling and printing process, tests are made with different printing parameters and often part of the test material is discarded. The objective of this work was to study a methodology for recycling discarded materials printed in 3D printer for use in characterization studies for dosimetry purposes.

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  • IPEN-DOC 26747

    SILVA, E. ; SANTOS, L.R. ; ASSEMANY, L.P.F. ; POTIENS, M.P.A. . Evaluation of the behavior of a 180cc ionization chamber under different environmental conditions. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: The use of ionizing radiation for medical purposes has been a major advance for society due to the numerous possibilities of use for the treatment and diagnosis of diseases. On the other hand, knowledge about the damage caused by the biological effects of ionizing radiation requires continuous improvement of diagnostic radiology quality control. Radiation detector equipment is used to measure radiation levels emitted from natural or artificial sources. For convenience and accuracy, among the most widely used detectors are ionization chambers. Especially outdoors, weather factors can affect the behavior of these detectors at the time of measurement, but Brazilian law recommends only calibrating these measuring instruments in a traceable laboratory every two years to ensure their reliability. The objective of this work was to evaluate the performance of an ionization chamber used in radioprotection measurements in diagnostic radiology equipment, considering climatic variations in different regions of Brazil. For this, a system was developed to simulate the environmental conditions found for the temperature and humidity parameters at the moment of the clinical measurements, allowing to estimate the influence of these factors on the obtained values.

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  • IPEN-DOC 26746

    ALMEIDA, J.S. ; VILLANI, D. ; POTIENS, M.P.A. ; WILLEGAIGON, J.. Dosimetric characterization of 3D printed for 137Cs gamma rays. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: The aim this paper is characterize materials for 3D printed with different infill percentages for 137Cs gamma rays. The RAISE 3D PRO2 printer was used to print PLA and ABS plates. Using a 137Cs source, the attenuation coefficient was obtained by the transmission method and results compared with PMMA. The readings were performed by a Radcal ionization chamber, model 10X6-6. The results of attenuation coefficients show that the PLA filament demonstrated a equivalent behavior to PMMA. The PLA plates exhibits an increase in radiation transmission when reduces the infilling, and ABS printing achieved same results for all infills.

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  • IPEN-DOC 26745

    MARTINS, E.W. ; KUAHARA, L.T. ; POTIENS, M.P.A. . Development of an "in situ" calibration methodology to activity meters. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: The performance of a safety and efficient practice of a nuclear medicine service depends, among other factors, on a complete quality control program, especially in the case of the radionuclide activity measuring instrument, the activimeter. Several factors may influence the accuracy of the measurements performed with an activimeter, and the largest sources of errors are related to the types of containers that contain radiopharmaceuticals (eg, thickness, size and volume). A complete quality control program should include the calibration of all measurement instruments used in the procedure. However, in Brazil, the actual standard that establishes the requirements of radiological protection for nuclear medicine services (NMS), does not include the calibration of the activimeter. Considering that these instruments, for various reasons, are difficult to remove for sending to a Calibration Service, the purpose of this work is to develop a methodology for activimeter calibration that can be applied "in situ" to the most used radiopharmaceutical, 99mTc.

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  • IPEN-DOC 26744

    VILLANI, D. ; SAVI, M. ; ANDRADE, M.A.B.; CAMPOS, L.L. ; POTIENS, M.P.A. . Characterization of ABS + W and ABS + Bi 3D printing filaments attenuation for different photon beams. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: 3D printing techniques and materials have become widely available in the last couple of decades and remains a hot topic of study as new materials can lead to new applications. This study aims to evaluate the attenuation behaviour of GMASS over photon beams ranging from 29.7 up to 661.7keV, comparing with pure ABS and using theoretical data of pure lead as reference. It was used the transmission method to obtain experimental attenuation coefficients to all materials and theoretical data. HVL and TVL calculations were also performed. Results show that ABS+W has higher attenuation than ABS+Bi and pure ABS. Using the lead theoretical reference data it can be concluded that although ABS+Bi and ABS+W attenuates less than pure lead, the 3D printing filaments can be used to create shielding tolls depending on radiation energy and application.

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  • IPEN-DOC 26743

    BUENO, LETICIA K. ; RODRIGUES JUNIOR, ORLANDO ; POTIENS, MARIA da P.A. . Avaliação da atenuação de invólucros produzidos em impressora 3D para medidas com calibrador de dose. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: Devido ao aumento de procedimentos realizados nos Serviços de Medicina Nuclear (SMN) tornou-se cada vez mais inevitável a preocupação com o perfeito funcionamento dos calibradores de dose utilizados diariamente. Ainda assim, a prática segura, eficiente e eficaz do uso do equipamento envolve a integração de vários processos. O objetivo deste trabalho é o projeto e desenvolvimento de novos invólucros por meio da prototipação utilizando uma impressora 3D. Os materiais escolhidos foram o PLA e o ABS. Foram realizados testes de precisão e exatidão variando os parâmetros de impressão e as dimensões do invólucro. Os resultados mostraram que é possível customizar os invólucros melhorando os resultados e reduzindo as incertezas no controle de qualidade desses equipamentos.

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  • IPEN-DOC 26725

    MARTOS, LUIS G.C.; BRASCHI, GIOVANI F.; CARNEIRO, MARCELO B.; MACHADO, IZABEL F.; BARBOSA, PATRICIA A.; ROSSI, WAGNER de . Avaliação de elemento cerâmico em gradação funcional / Evaluation of ceramic element functionally graded. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICAÇÃO, 10., 5-7 de agosto, 2019, São Carlos, SP. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2019.

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  • IPEN-DOC 26603

    TODO, ALBERTO S. ; CARDOSO, JOAQUIM C.S. ; RODRIGUES JUNIOR, ORLANDO . Analysis of the in vivo monitoring program at IPEN in the last 14 years. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 93-98.

    Abstract: This paper presents the results of the in vivo monitoring analysis for Occupationally Exposed Individuals that handle unsealed sources at Nuclear and Energy Research Institute (IPEN). The facilities are: the Radiopharmacy Center, the Cyclotron, the IEA-R1 Reactor and Research Laboratories. The in vivo monitoring program is carried out in a whole-body counter for radionuclides emitting gamma rays with energy above 100 keV. This system is equipped with 8x4 and 3x3 inch NaI(Tl) detector, for whole body and thyroid measurements, respectively. The objective of this work is to analyze the results of the internal monitoring program according to the dose received by the Occupationally Exposed Individuals from 2005 to 2018. During this period about 6,000 measurements were accomplished. The radionuclides that presented measured values above the detection limit of the system were: 131I, 99Mo, 99mTc, 153Sm, 177Lu, 111In, 192Ir, 125I, 123I, 181Hf, 203Hg, 67Ga, 18F, 51Cr, 201Tl. These measurements have amounted less than 6.9% of the total whole-body monitoring’s performed in this period. Among these radionuclides, 131I, 99mTc, 125I and 18F have contributed with 69% of all measurements above the limit of detection, but most dose results were below the recording level under installations normal operating conditions. Regarding to the radionuclides that have presented doses above the recording level we can mention the 131I, 67Ga, 111In that occurred in small unexpected situations. The results shown by this analysis give a good support to the internal individual monitoring program implemented by the radioprotection service in these facilities.

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  • IPEN-DOC 26548

    BORAZANIAN, TATYANA C.F. ; SZURKALO, MARGARIDA ; CORREA, OLANDIR V. ; BENTO, RODRIGO T. ; PILLIS, MARINA F. . Revestimentos de TiO2 para a preservação de superfícies arquitetônicas. In: CONGRESSO BRASILEIRO DE CATALISE, 20., 1-5 setembro, 2019, São Paulo, SP. Anais...

    Abstract: A utilização do dióxido de titânio (TiO2) tem sido amplamente estudada para proteção de elementos arquitetônicos e de revestimentos externos utilizados na construção civil, a fim de preservar melhor seu aspecto visual e minimizar a necessidade constante de limpeza e manutenção decorridas da deposição de partículas de poluentes existentes na atmosfera. Este trabalho tem como objetivo avaliar o desempenho autolimpante de filmes fotocatalíticos de TiO2 aplicados em superfícies de materiais comumente empregados na Arquitetura.

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  • IPEN-DOC 26547

    BENTO, RODRIGO T. ; CORREA, OLANDIR V. ; PILLIS, MARINA F. . Reativação e reutilização de fotocatalisadores de TiO2 dopados com enxofre em baixa temperatura. In: CONGRESSO BRASILEIRO DE CATALISE, 20., 1-5 setembro, 2019, São Paulo, SP. Anais...

    Abstract: O presente estudo avaliou a possibilidade de reutilização fotocatalítica dos filmes de dióxido de titânio (TiO2) dopados com enxofre em baixa temperatura. Os filmes foram crescidos por deposição química de organometálicos em fase vapor (MOCVD) a 400°C. A dopagem com enxofre foi realizada a 50°C por um processo semelhante ao utilizado na dessulfuração do sulfeto de hidrogênio (H2S). O comportamento fotocatalítico e a durabilidade dos filmes foram medidos a partir da degradação do corante alaranjado de metila sob luz visível por vários ciclos. Os filmes são formados apenas pela fase cristalina anatase. Os resultados demonstraram que não houve modificações estruturais ou diferenças significativas na morfologia dos filmes após a sua utilização. Os filmes de TiO2 dopados com enxofre apresentaram uma excelente atividade fotocatalítica, com uma eficiência de 72,1% sob luz visível. Os experimentos de durabilidade sugerem que, mesmo com a impregnação de corante na superfície do catalisador, os filmes de TiO2 dopados apresentaram boa estabilidade fotocatalítica após diversas horas de uso, o que permite sua aplicação prática no tratamento e purificação da água sob luz solar com elevada eficiência.

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  • IPEN-DOC 26546

    ALENCAR, CATARINE S.L. ; PAIVA, ANA R.N. ; VAZ, JORGE M. ; SPINACE, ESTEVAM V. . Preparação de nanopartículas de cobre e ouro suportadas em TiO2 para uso como catalisador na oxidação preferencial de CO em misturas ricas em hidrogênio (CO-PROX). In: CONGRESSO BRASILEIRO DE CATALISE, 20., 1-5 setembro, 2019, São Paulo, SP. Anais...

    Abstract: Os catalisadores Au/TiO2 têm apresentado boa atividade e seletividade para a reação de oxidação preferencial de monóxido de carbono em misturas ricas em hidrogênio (CO-PROX). É proposto um catalisador contendo os metais Au e Cu (CuAu/TiO2) que será preparado por meio de redução química de forma simultânea de ambos os metais, utilizando borohidreto de sódio como agente redutor. Realizou-se também a síntese de catalisadores monometálicos de Cu/TiO2 e Au/TiO2 sob as mesmas condições e os resultados foram comparados. Os catalisadores foram caracterizados por Difração de Raios X (DRX), Energia Dispersiva de Raios X (EDX), Microscopia Eletrônica de Transmissão (MET) e Redução por temperatura programada (TPR). O catalisador CuAu/TiO2 apresentou melhor atividade catalítica para a reação CO-PROX se comparado aos seus respectivos catalisadores monometálicos.

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  • IPEN-DOC 26545

    QUEIROZ, CARLA M.S. ; MACHADO, ARTHUR P. ; PAIVA, ANA R.N. ; VAZ, JORGE M. ; SPINACE, ESTEVAM V. . Preparação de catalisadores Pt/CeO2 promovidos por Fe e Sn via método de redução por álcool para a oxidação preferencial de CO em misturas ricas em hidrogênio (PROX-CO). In: CONGRESSO BRASILEIRO DE CATALISE, 20., 1-5 setembro, 2019, São Paulo, SP. Anais...

    Abstract: A reação de oxidação preferencial do CO (PROX-CO) é considerada uma alternativa eficiente e econômica para remoção de CO presente em correntes de H2 que são empregadas para a produção de energia limpa e sustentável via tecnologia de células a combustível. Isto porque, a reação de PROX-CO catalisada é capaz de reduzir a concentração deste contaminante para níveis menores que 50 ppm, evitando assim o envenenamento e consequente desativação dos eletrodos da célula. Os catalisadores de Pt têm se mostrado bastante promissores para emprego na reação de PROX-CO, apresentado altas conversões e seletividades, numa ampla faixa de temperatura. Assim, este trabalho tem o objetivo de estudar o desempenho de catalisadores de Pt/CeO2 promovidos com óxidos de Fe ou Sn destinados à reação de PROX-CO. Os sólidos foram sintetizados pelo método de redução por álcool e caracterizados pelas técnicas de EDX, DRX e MET. Os desempenhos catalíticos foram conduzidos sob pressão atmosférica e em temperaturas variando entre 50 °C e 200 °C. Os resultados revelam que os catalisadores de Pt suportados em céria apresentaram máxima conversão de CO e seletividade em CO2 a 50 °C.

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  • IPEN-DOC 26541

    EMILIOZZI, CAROLINE Z.S.; MENEZES, MARIO O. de ; MOREIRA, EDSON G. . Investigation of the parameters affecting patients waiting time in the radiotherapy treatment by using algorithms to evaluate electronic health records. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 1659-1668.

    Abstract: Cancer is the second leading cause of death worldwide and Radiotherapy (RT) is an important modality in the treatment of these patients, which consists in deploying ionising radiation to destroy or damage cancer cells. With this growing global burden, demand for RT has been increasing continuously and supply-demand imbalances have become a major concern. The reason is that delays in radiotherapy can affect the outcome by permitting local proliferation of clonogenic cells and spread of the cancer beyond the treatment volume. Studies show a common cause of anxiety for radiotherapy patients is the fact that they do not know how long they will have to wait for treatment to start. In this study, we analyze the data of electronic health records to attempt to provide a better understanding of the problem and provide an initial estimate of radiotherapy patient’s waiting time. The data for this project comes from a subset of MOSAIQ, a relational database system developed by Elekta and used as an electronic health record system by the Radiation Oncology Department at the Hospital das Clínicas de São Paulo (HCFMUSP). The dataset consists of real historical data collected between January 2016 and December 2018. Visual Basic for application (VBA) and RSTUDIO Software were used to extract and analyze the data. Our work goal is to investigate a set of factors and verify their influence on patient waiting time. Factors as diagnosis, patient’s age, priority of the diagnosis, and the season in which treatment planning has initiated may reveal crucial information about overall efficiency and guide us to improve clinical procedures and practices.

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  • IPEN-DOC 26539

    CASTRO, MAYSA C. de ; SILVA, NATALIA F. da ; CALDAS, LINDA V. E. . Dosimetric tests of an extrapolation chamber in standard computed tomography beams. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 116-120.

    Abstract: Computed tomography (CT) diagnostic exams are responsible for the highest dose values to the patients. Therefore, the radiation doses in this procedure must be accurate. For the dosimetry of CT beams, the radiation detector is usually a pencil-type ionization chamber. This type of dosimeter presents a uniform response to the incident radiation beam from all angles, which makes it suitable for such equipment since the X-ray tube executes a circular movement around the table during irradiation. However, there is no primary standard system for this kind of radiation beam yet. In order to search for a CT primary standard, an extrapolation chamber built at the Calibration Laboratory (LCI) of the Instituto de Pesquisas Energéticas e Nucleares (IPEN) was tested. An extrapolation chamber is a parallel-plate ionization chamber that allows the variation of its sensitive air volume. This chamber was used previously for low-energy radiation beams and showed results within the international recommended limits. The aim of this work is to perform some characterization tests (saturation curve, polarity effect, ion collection efficiency and linearity of response) considering the chamber depth of 1.25 mm in the radiation qualities for computed tomography beams at the LCI. The results showed to be within the international recommended limits.

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  • IPEN-DOC 26535

    SILVA, PAULO S.C. da ; CAMPOS, MARCIA P. de ; REIS, GUILHERME de L. . Radon concentrations on the nuclear and radioactive instalations of nuclear reactor center – CRPQ/IPEN. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 105-115.

    Abstract: Nuclear and radioactive workers are normally exposed to dose resulting from their day by day activities. Besides that, the ubiquitous radon distribution can also contribute for the exposure rates. The radionuclide 222Rn is a noble gas belonging to the uranium series and its indoor concentration in the air depend on exhalation from surrounding soil and on exhalation from building materials. Radon emanating from porous building materials may achieve large relevance in areas with high uranium concentrations and areas with limited ventilation. The objective of this study was to evaluate the 222Rn concentrations in the radiochemistry and radiometric laboratories and in the reactor nuclear building of the Nuclear Reactor Center (CERPq) located in the Nuclear and Energy Research Institute (IPEN). Measurements were done by using a Radon Gas Monitor, model RAD7, produced by Durridge Company equipped with a solid state alpha detector and a passive method, with SSNTDs placed within small diffusion chambers, as detectors square pieces (2.5 cm × 2.5 cm) of CR 39 foils were used. The CR 39 detectors were etched in KOH 30% solution at 80 °C for 5.5 h in a constant temperature bath. After etching, the detectors were washed, dried, and scanned under a Carl Zeiss microscope to obtain the track density measurements. The activity concentrations varied from 52 to 103 Bq m 3 for the measured areas in CERPq. These values are in accordance with what is stablished by the World Health Organization for safe environments of 100 Bq m 3.

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  • IPEN-DOC 26517

    CAPPUZZELLO, F.; AGODI, C.; ACOSTA, L.; AMADOR-VALENZUELA, P.; AUERBACH, N.; BAREA, J.; BELLONE, J.I.; BELMONT, D.; BIJKER, R.; BONANNO, D.; BORELLO-LEWIN, T.; BOZTOSUN, I.; BRANCHINA, V.; BRASOLIN, S.; BRISCHETTO, G.; BRUNASSO, O.; BURRELLO, S.; CALABRESE, S.; CALABRETTA, L.; CALVO, D.; CAPIROSSI, V.; CARBONE, D.; CAVALLARO, M.; CHEN, R.; CIRALDO, I.; CHAVEZ LOMELI, E.R.; COLONNA, M.; D'AGOSTINO, G.; DJAPO, H.; DE GERONIMO, G.; DELAUNAY, F.; DESHMUKH, N.; FARIA, P.N. de; ESPEJEL, R.; FERRARESI, C.; FERREIRA, J.L.; FERRETTI, J.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; FLORES, A.; FOTI, A.; GALLO, G.; GARCIA-TECOCOATZI, H.; GONGORA, B.; HACISALIHOGLU, A.; HAZAR, S.; HUERTA, A.; KOTILA, J.; KUCUK, Y.; IAZZI, F.; LANZALONE, G.; LA VIA, F.; LAY, J.A.; LENSKE, H.; LINARES, R.; LONGHITANO, F.; LO PRESTI, D.; LUBIAN, J.; MA, J.; MARIN-LAMBARRI, D.; MARTINEZ, S.; MAS, J.; MEDINA, N.H.; MENDES, D.R.; MEREU, P.; MORALLES, M. ; OLIVEIRA, J.R.B.; ORDONEZ, C.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PIETRALLA, N.; PINNA, F.; REITO, S.; REZA, G.; RIES, P.; RIFUGGIATO, D.; RODRIGUES, M.R.D.; RUSSO, A.D.; RUSSO, G.; SANDOVAL, S.; SANTOPINTO, E.; SANTOS, R.B.B.; SGOUROS, O.; SILVEIRA, M.A.G. da; SOLAKCI, S.O.; SOULIOTIS, G.; SOUKERAS, V.; SPATAFORA, A.; TORRESI, D.; TUDISCO, S.; VSEVOLODOVNA, R.I.M.; VARGAS, H.; VEGA, G.; WANG, J.S.; WERNER, V.; YANG, Y.Y.; YILDIRIN, A.; ZAGATTO, V.A.B.. The NUMEN project @ LNS: status and perspectives. In: MARUYAMA, REINA (Ed.) SYMMETRIES AND ORDER: ALGEBRAIC METHODS IN MANY BODY SYSTEMS, October 5-6, 2018, Connecticut, USA. Proceedings... Melville, NY, USA: AIP Publishing, 2019. p. 030003-1 - 030003-6. (AIP Conference Proceedings, 2150). DOI: 10.1063/1.5124592

    Abstract: The NUMEN project aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involved in the half-life of the neutrinoless double beta decay (0υββ), by high-accuracy measurements of the cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. Particular interest is given to the (18O,18Ne) and (20Ne,20O) reactions as tools for β+β+ and β-β- decays, respectively. First evidence about the possibility to get quantitative information about NME from experiments is found for both kind of reactions. In the experiments, performed at INFN - Laboratory Nazionali del Sud (LNS) in Catania, the beams are accelerated by the Superconducting Cyclotron (CS) and the reaction products are detected by the MAGNEX magnetic spectrometer. The measured cross sections are challengingly low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. A major upgrade of the LNS facility is foreseen in order to significantly increase the experimental yield, thus making feasible a systematic study of all the cases of interest. Frontiers technologies are going to be developed, to this purpose, for the accelerator and the detection systems. In parallel, advanced theoretical models are developed aiming at extracting the nuclear structure information from the measured cross sections.

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  • IPEN-DOC 26534

    SANTOS, GIVANILDO A. dos; GUIMARÃES, MARCOS de A.; AGUIAR, HERBERT C.G. de; NASCIMENTO, MAURICIO S.; SANTOS, VINICIUS T. dos; SILVA, MARCIO R. da; COUTO, ANTONIO A. ; BATALHA, GILMAR F.. Análise do acabamento superficial na usinagem de liga de bronze-alumínio-níquel sem utilização de fluido de corte / Analysis of surface finish in machining of bronze-aluminum-nickel alloy without using cutting fluid. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICAÇÃO, 10., 5-7 de agosto, 2019, São Carlos, SP. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2019.

    Abstract: As ligas bronze-alumínio-níquel têm usinabilidade de 20 a 40% comparada com o latão de corte livre, de forma que os parâmetros de corte destas ligas podem diferir bastante dos utilizados para outras ligas de cobre e a ausência de contaminação por fluidos de corte possibilita um maior valor na venda dos cavacos, encorajando a utilização de usinagem sem refrigeração. Neste trabalho foi avaliado o comportamento quanto ao acabamento superficial na usinagem da liga bronze-alumínio-níquel CuAl10Ni5Fe5 com pastilha de metal duro em diferentes velocidades de corte, sem utilização de fluido de corte (refrigerante). Os resultados mostraram menor valor e maior estabilidade da rugosidade em condições de velocidades de corte mais altas.

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  • IPEN-DOC 26363

    ABE, ALFREDO Y. ; MELO, CAIO; GIOVEDI, CLAUDIA; SILVA, ANTONIO T. . Modification of TRANSURANUS fuel performance code in the ATF framework. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5036-5045.

    Abstract: The standard fuel system based on UO2–zirconium alloy has been utilized on nearly 90% of worldwide nuclear power light water reactors. After the Fukushima Daiichi accident, alternative cladding materials to zirconium-based alloys are being investigated in the framework of accident tolerance fuel (ATF) program. One of the concepts of ATF is related to cladding materials that could delay the onset of high temperature oxidation, as well as ballooning and burst, in order to improve reactor safety systems, and consequently increase the coping time for the reactor operators in accident condition, especially under Loss-of-Coolant Accident (LOCA) scenario. The ferritic iron-chromium-aluminum (FeCrAl) alloys have been identified as an alternative to replace current zirconium-based alloys based on its outstanding resistance to oxidation under superheated steam environment due to the development of alumina oxide on the alloy surface in case of LOCA; moreover, FeCrAl alloys present quite well performance under normal operation conditions due to the thin oxide rich in chromium that acts as a protective layer. The assessment and performance of new fuel systems rely on experimental irradiation program and fuel performance code simulation, therefore the aim of this work is to contribute to the computational modeling capabilities in the framework of the ATF concept. The well-known TRANSURANUS fuel performance code that is used by safety authorities, industries, laboratories, research centers and universities was modified in order to support FeCrAl alloy as cladding material. The modification of the TRANSURANUS code was based on existing data (material properties) from open literature and as verification process was performed considering LOCA accident scenario.

    Palavras-Chave: accident-tolerant nuclear fuels; aluminium alloys; chromium alloys; cladding; comparative evaluations; fuel rods; iron alloys; loss of coolant; performance; t codes; zirconium alloys

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  • IPEN-DOC 26357

    LIMA, LEONARDO S.; MELO, CAIO; FARIA, DANILO P.; BERRETA, JOSE; ABATI, AMANDA ; GIOVEDI, CLAUDIA . Analysis of stresses acting on the internal and external surfaces of fuel rod of a pressurized water reactor using computational simulation. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 4950-4961.

    Abstract: During operation of a Pressurized Water Reactor, the cladding of the fuel rod is subjected to various loads, such as: temperature, internal pressure, and external pressure which generate dimensional and geometric variations in the cladding tube. In the fuel rod, at the operating temperature, the internal pressure comes from the initial pre-pressurizing with Helium gas and the release of fission gases by the UO2 pellets during the irradiation. The external pressure is assumed to be the same as that of the coolant. In this paper, it was proposed the study of a mathematical model for computational simulation using the Finite Element Method to calculate and analyze the mechanical stresses acting on the internal and external surfaces of the fuel rod, adopting the normal operating condition, at 0 W of power. The boundary conditions, such as temperature and pressure profile, come from a modified version of a fuel performance code, considering as cladding material an iron-based alloy (austenitic stainless steel). The fuel rod was modeled and simulated using the Solidworks and ANSYS softwares, respectively. The values of the stresses acting on the cladding tube obtained by simulation were compared to the values obtained by analytical calculation. Then, it was checked the consistency of the adopted mathematical model, in order to ensure the reliability of the computational simulation as a tool to evaluate the stresses acting on the internal and external surfaces of the fuel rod under a PWR environment.

    Palavras-Chave: a codes; austenitic steels; boundary conditions; cladding; computerized simulation; finite element method; fuel rods; iron alloys; pwr type reactors; s codes; stresses

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  • IPEN-DOC 26356

    GIOVEDI, CLAUDIA; MELO, CAIO; ABE, ALFREDO Y. ; SILVA, ANTONIO T. ; MARTINS, MARCELO R.. Fuel performance of iron-based alloy cladding using modified TRANSURANUS code. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 4943-4949.

    Abstract: The main challenge in the nuclear area since the Fukushima Daiichi accident is to develop fuel materials to be applied in nuclear reactors aiming to increase the safety under normal operation as well as transient and accident conditions. These efforts are concentrated in the Advanced Technology Fuel (ATF) program that has as main scopes to study cladding materials to replace the zirconium-based alloys, and fuel materials presenting higher thermal conductivity compared to the conventional uranium dioxide fuel pellet. In this sense, iron-based alloys, which were used with a good performance as cladding material in the first Pressurized Water Reactors (PWR), have becoming a good option. The assessment of the behavior of different materials previously to perform irradiation tests, which are time consuming, can be performed using fuel performance codes, but for this, the conventional fuel performance codes must be modified to implement the properties of the materials that are being studied. This paper presents the results obtained using a modified version of the well-known TRANSURANUS code, obtained from the implementation of the stainless steel 348 properties as cladding material. The simulations were performed using data available in the open literature related to a PWR irradiation experiment. The results obtained using the modified version of the code were compared to those obtained using the original code version for zircaloy-4. The performance of both cladding materials was evaluated by means of the comparison of parameters such as gap thickness, fuel centerline temperature, internal pressure, and cladding stress and strain.

    Palavras-Chave: cladding; comparative evaluations; computerized simulation; fuel rods; iron alloys; nuclear fuels; performance; pwr type reactors; stainless steel-348; steady-state conditions; t codes; zircaloy 4

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  • IPEN-DOC 26350

    OLIVA, AMAURY M.; ALVES FILHO, HERMES; BARROS, RICARDO C.; CURBELO, JESUS P.. The spectral deterministic method applied to nêutron fixed-source discrete ordinates problems in X, Y-geometry for multigroup calculations. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 4702-4716.

    Abstract: A new approach for the development of a coarse-mesh numerical spectral nodal method is presented in this paper. This method, referred to as the Spectral Deterministic Method { Constant Nodal (SDM{CN), is based on a spectral analysis of the multigroup X,Y-Geometry, linearly anisotropic scattering neutron transport equations in discrete ordinates ( SN)formulation for xed-source calculations in non-multiplying media. In this paper we present typical model problems to illustrate the accuracy and the e ciency for coarse-mesh energy multigroup SN calculations of the SDM-CN method. The numerical results obtained are compared with the traditional ne-mesh Diamond Di erence (DD) method and the results obtained by DOT{II and TWOTRAN codes. The numerical results are also compared with the spectral nodal method, spectral Green's function (SGF).

    Palavras-Chave: boltzmann equation; comparative evaluations; comparative evaluations; computerized simulation; d codes; discrete ordinate method; finite difference method; multigroup theory; neutron transport; nodal expansion method; scattering; t codes

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  • IPEN-DOC 26223

    DOURADO, NELSON X. ; OMI, NELSON M. ; SOMESSARI, SAMIR L. ; GENEZINI, FREDERICO A. ; FEHER, ANSELMO ; NAPOLITANO, CELIA M. ; AMBIEL, JOSE J. ; CALVO, WILSON A.P. . Preliminary studies on the development of an automated irradiation system for production of gaseous radioisotopes applied in industrial processes. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 1583-1592.

    Abstract: The purpose of the present study is to demonstrate how it will be enhanced an Irradiation System (IS) developed with national technology to produce gaseous radioisotopes, by means of the components automation, to avoid the radiation exposure rate to operators of the system, following the ALARA principle (As Low As Reasonably Achievable). Argon-41 (41Ar) and krypton-79 (79Kr) can be produced in continuous scale, gaseous radioisotopes used as radiotracers in industrial process measurements and it can be used in analytical procedures to obtain qualitative and quantitative data systems or in physical and physicochemical studies transfers. The production occurs into the IS, installed in the pool hall of a nuclear research reactor in which the irradiation capsule is positioned near the reactor core containing the isotope gaseous pressurized (40Ar or 78Kr), by (n,γ) reaction and generate the radioisotopes. After the irradiation, the gaseous radioisotope is transferred to the system and, posteriorly, to the storage and transport cylinders, that will be used in an industrial plant. In the first experimental production, was obtained 1.07x1011 Bq (2.9 Ci) of 41Ar distributed in two storage and transport cylinders, operating the IEA-R1 Research Reactor with 4.5 MW and average thermal neutron flux of 4.71x1013 n.cm-2.s-1. However, the system has capacity to five storage and transport cylinders and the estimated maximum activity to be obtained is 7.4x1011 Bq (20 Ci) per irradiation cycle. In this sense, the automation will be based in studies of the production process in the system and the use of Programmable Logic Controllers (PLC), and supervisory software allowing a remote control and consequently better security conditions.

    Palavras-Chave: argon 41; automation; irradiation; krypton 79; neutron flux; production; remote control; thermal neutrons; tracer techniques

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  • IPEN-DOC 26391

    OLIVEIRA, GLAUCIA A.C. de ; LAINETTI, PAULO E.O. ; BUSTILLOS, JOSE O.W.V. ; PIRANI, DEBORA A. ; BERGAMASCHI, VANDERLEI S. ; FERREIRA, JOAO C. ; SENEDA, JOSE A. . Thorium and lithium in Brazil. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5915-5922.

    Abstract: Brazil has one of the largest reserves of thorium in the world, including rare earth minerals. It has developed a great program in the field of nuclear technology for decades, including facilities to produced oxides to microspheres and thorium nitrates. Nowadays, with the current climate change, it is necessary to reduce greenhouse gas emissions, one of this way is exploring the advent of IV Generation reactors, molten salt reactors, that using Thorium and Lithium. Thorium's technology is promising and has been awaiting the return of one nuclear policy that incorporates its relevance to the necessary levels, since countries like the BRICS (without Brazil) have been doing so for years. Brazil has also been developing studies on the purification of lithium, and this one associated to thorium, are the raw material of the molten salt reactors. This paper presents a summary of the thorium and lithium technology that the country already has, and its perspectives to the future.

    Palavras-Chave: lithium; molten salt reactors; nuclear fuels; public policy; purification; thorium; uranium; brazil

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  • IPEN-DOC 26390

    CUNHA, CAIO J.C.M.R.; RODRÍGUEZ, DANIEL G.; LIRA, CARLOS A.B.O.; STEFANI, GIOVANNI L. ; LIMA, FERNANDO R.A.. Thermohydraulic analysis of a fuel element of the AP1000 reactor with the use of mixed oxides of U / Th using the computational fluid dynamic code (CFX). In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5901-5914.

    Abstract: The present work carried out a thermohydraulic analysis of a typical fuel assembly of the reactor AP1000 changing the type of fuel, of UO2 conventionally used for a mixture of oxides of (U,Th)O2 realizing some simplifications in the original design, with the objective to develop of an initial methodology capable of predicting the thermohydraulic behavior of the reactor within the limits established by the manufacturer. An expression for the power density was determined using a coupled neutronic thermohydraulic calculation; once the final expression for power density was determined, the axial and radial temperature profiles in the assembly, as well as the pressure drop and the distribution of the coolant density, were evaluated. Due to the increase in research done on thorium, such as the work of [1], [2], [3], [4] and [5], as well as the mass diffusion of the AP1000, as is the case with [6] and [7]. The present study developed a simplified model, where burnable poisons and spacer grids were not considered, however, it is a consistent model, but with the insertion of these, a more accurate representation of the reactor is expected, providing operational transient analyzes. This tends to strengthen the lines of research that have been carrying out work on the AP1000, as well as in the general sphere of nuclear power plants.

    Palavras-Chave: boundary conditions; burnable poisons; c codes; calculation methods; fuel assemblies; fuel substitution; mixtures; monte carlo method; power density; pwr type reactors; temperature distribution; thermal hydraulics; thorium; transients; uranium dioxide

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  • IPEN-DOC 26389

    SOUZA, PAULA C.A. de; AGUIAR, ANDRE S. ; HEIMLICH, ADINO; LAPA, CELSO M.F.; LAMEGO, FERNANDO. Assessment of potential risk and radiological impact of accidental release from the ARGONAUT reactor. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5877-5885.

    Abstract: In the early days of nuclear energy in Brazil, a reactor designed at the Argonne National Laboratory, originating the name ARGONAUT from the combination of the name of the Laboratory with the initials of Nuclear Assembly for University Training, reached criticality at the Institute of Nuclear Engineering. The Argonaut is a water moderated research reactor, which uses uranium enriched to 20% (235U) with prismatic graphite reflectors, designed to provide a thermal neutron flux up to 1010 n.cm-2.s-1 at an operating power of 5 kW. The presence of a nuclear research facility at the campus of Federal University of Rio de Janeiro (UFRJ) still cause concerns about radiological safety of the community around, even though this facility has been securely operating for more than fifty years. Besides, there were questioning about the potential risk of this facility to the IEN´s workforce by the Central of Harmonization Unit of Brazil (CGU). Thus, the present work aims to assess the potential risk of radiological accidents. Previously, the potential accidents evolving Argonaut reactor were considered to be the insertion of excess reactivity, catastrophic rearrangement of the core, graphite fire and fuel-handling accident. However, a recent accident scenario reassessment concluded that a severe physical damage of the core after reactor shutdown should be the emergency situation with the greater potential risk among the feasible postulated accidents. According with the shutdown procedure, the water, used as moderator and coolant, drains out of the core and the concrete covers (each weighing 2.5 tons) are routinely removed from the top of reactor using a crane. The damage caused by the failure of the crane dropping the covers on the core would lead to breaking of the aluminum coating and the nuclear fuel plates with their release to the reactor room. This study assesses the radiological impact to workers and members of the public caused by partial inventory release to the atmosphere. Generic gaussian model was used to estimate the relative concentrations of air at ground level through the calculation of dispersion factors derived from wind data. For the dose calculation, the conversion coefficients by inhalation and plume immersion established by the ICRP were used. The results show that potential risk is above 1/10 of the limit of annual dose for workers, while they stay below the limit for members of the public, within a radius greater than 1 km.

    Palavras-Chave: argonaut reactor; dose rates; fission product release; fuel elements; gaussian processes; ionizing radiations; personnel; radiation accidents; radiation doses; reactor accidents; risk assessment; volatile matter

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  • IPEN-DOC 26388

    AGUIAR, ANDRE S. ; LEE, SEUNG M. ; SABUNDJIAN, G. . Analysis of the protective actions in the Emergency Planning Zones (EPZs) in the Angra dos Reis region through the calculation of the dose for public individuals due to a severe accident at the Angra 2 Nuclear Plant. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5862-5876.

    Abstract: This work presents the results of the computational simulations of the consequences of a severe accident in Angra 2 nuclear power plant. The severe accident was supposed to be caused by a rupture of 380cm2 in the primary reactor coolant system resulting in loss of coolant. Since the area of the rupture is quite smaller than the total flow area of the pipe of the primary coolant system, 4418cm2, the accident is classified as a small break loss of coolant accident. However, this rupture by itself would not bring the system about a severe accident, which must involve a considerable damage in the nuclear core. Thus, some boundary conditions were added to the problem in order to set a scenario of this kind of accident, which was simulated by means of the MELCOR code. The results obtained by this code show that the release of the radionuclide to the environment starts at the opening of the containment relief valve, and this valve, in turn, opens when the containment pressure reaches 7bar, at 168 hours after the break of the pipe of the coolant system, according to the simulation. The program used for calculation of the release of the radionuclides to the surrounding region of the nuclear plant was the CALMET/CALPUFF code, so that the atmospheric and transport model were elaborated for this code. A source term was used in order to carry out an analysis of the protective actions in the emergency planning zones by means dose calculation for individuals of the public, and it was based on two different scenarios: first scenario, release of the total activity to the atmosphere of Xe, Cs, Ba and Te, after 2h simulation and second scenario, release of the total activity to the atmosphere of Xe, Cs, Ba and Te, after 168h of simulation.

    Palavras-Chave: angra-2 reactor; boundary conditions; c codes; emergency plans; fission product release; loss of coolant; m codes; radiation doses; radiation protection; radioactive materials; radioactivity; reactor accident simulation; severe accidents

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  • IPEN-DOC 26387

    VAZ, ANTONIO C.A. ; RODRIGUES, VALDEMIR G. ; TOYODA, EDUARDO Y. ; SAXENA, RAJENDRA N. . Human factors inclusion proposal in “reactor trip” to increase safety in operation. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5819-5826.

    Abstract: A fundamental concept in nuclear reactor operation is that safety is the result of interactions between human, technological and organizational factors. The National Nuclear Energy Commission understands how human factors from psychological, physiological, behavioral and emotional origin can affect the reactor operation. For that reason, reactor operators are submitted to rigorous evaluations every ye ar. When conducting case study du ring these sixty years of IEA R1, three of them hypothetical and possible related to the reactor operation illustrates the co ncern about the safety and security : Case 1 Operator had a stroke during reactor operation in the control room. C ase 2 Operator suffered stress in traffic in his going to the reactor facility; when performing test in the emergency cooling system for reactor start up, he didn’t close a valve completely; changing the pool water technical quality causing a week delay in the reactor op eration . Case 3 Operator just arrived to afternoon shift in the control room, after a few minutes his co worker noticed that his cognition and behavior has changed, later in the hospital he was diagnosed with head cancer. This interdisciplinary work aims to include human factors of psychological , physiological and behavioral origin in 'reactor trip'. The ‘reactor trip’ (also know n as ‘scram’) usually applies to technical factors to avoid high consequence event, are protection circuits that can assume the s tatus of alert, hazard and essentially shut down the reactor automatically; when temperature, radioactivity, pressure, water flow, voltage and so on ; are out of the operating limits. Technologies associated with neuroscience and psychological assessments s uch as: Face Reader, Analogue Visual Mood Scale and Back Depression Inventory ; allows the evaluation of the operator in the control room. However, problems li ke described in the case study should be minimized. This inter disciplinary theoretical work is based on empirical doctoral thesis in progress.

    Palavras-Chave: control rooms; human factors; iear-1 reactor; radiation protection; reactor accidents; reactor operators; reactor safety; scram; security

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  • IPEN-DOC 26386

    SOBREIRO JUNIOR, ADALBERTO R. ; FREIRE, LUCIANO O. ; ANDRADE, DELVONEI A. de . Proposal for a nuclear power-plant ship decomissioning. In: ABEN (Ed.) INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro, 2019. p. 5793-5804.

    Abstract: The goal of this work is to review decommissioning methods for nuclear propulsion ships throughout of survey on decommissioning experience. Governmental regulation typically dictates cleanup of a decommission site. It is satisfying the stringent regulations that prove to be a primary cost driver for decommissioning and waste disposal. Reactor types and sizes, the number of reactors on an individual plant site, and labor costs are among the main factors affecting costs. Thus, it is so important to develop a good recycling policy after nuclear-power plant ship inactivation. This work found that adequate requirements identification must keep economics always in the center of design. Experience shows, except after major catastrophic accidents, nuclear industry may earn public trust by open dialogue with the population and sound engineering practices, searching for right technical solution and great planning for long time. To achieve this goal, this work proposed the following method: firstly, it presents the characteristics of nuclear-powered submarines. Secondly, an approach concerning the decommissioning process of nuclear-powered submarines adopted by the US Navy, Russian Navy, Royal Navy, French Navy and others which brings the past experience on this field, providing some information on history, architectures and hints of reasons for the success or failures of each project. Finally, this works compared the decommissioning processes of these navies under the perspective of the nuclear regulatory process.

    Palavras-Chave: ships; ship propulsion reactors; decommissioning; government policies; toxic materials; nuclear power; nuclear submarines; waste disposal

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  • IPEN-DOC 26385

    SCURO, NIKOLAS L. ; ANGELO, GABRIEL ; ANGELO, E.; TORRES, WALMIR M. ; UMBEHAUN, PEDRO E. ; ANDRADE, DELVONEI A. de . Preliminary numerical analysis of the flow distribution in the core of a research reactor. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5667-5674.

    Abstract: The thermal-hydraulic safety analysis of research reactors establishes the safety criteria to ensure the integrity of the fuel elements in the reactor core. It assures that all core components are being adequately cooled during operation. It is necessary to know if the average mass flow rate (and their standard deviation) among the fuel assemblies are enough to cool the power generated during operation. Once satisfied such condition, it allows the calculation of the maximum heat flux transferred from fuel assemblies to the coolant, and if the maximum cladding temperatures are below the limits set by the safety criteria. Among the objectives, this study presents a methodology for a preliminary three-dimensional numerical analysis of the flow distribution in the core of the IEA-R1 research reactor, under steady state condition. For this, the ANSYS-CFX® commercial code was used to analyze the flow dynamics in the core, and to visualize the velocity field. It was possible to conclude that a homogeneous flow distribution for all standard fuel assemblies were found, with 2.7% deviation from the average mass flow. What turned out to be negligible and can be assumed that there is a homogeneous distribution in the core. Complex structures were find in the computational domain. Once known the core flow dynamics, it allows future studies to determine whether the heat flux and temperature conditions abbeys thermal-hydraulic safety criteria.

    Palavras-Chave: boundary conditions; c codes; flow models; fuel assemblies; iear-1 reactor; numerical analysis; reactor cores; research reactors; safety; steady-state conditions; thermal hydraulics

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  • IPEN-DOC 26384

    CARVALHO, DANIEL S.M. de; MATTAR NETO, MIGUEL . Assessment of ANSYS LS-DYNA capabilities for analysis of drop tests of nuclear fuel element transportation casks. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5551-5563.

    Abstract: During the transportation of fuel elements, the cask has to provide shielding to protect workers, the public and the environment against the effects of radiation, to prevent an unwanted chain reaction, damage caused by heat and also to provide protection against dispersion of the contents. In order to standardize the design of fuel assembly transportation devices by numerical analysis, a set of dynamic analyzes was conducted to converge in a representative way the phenomena found in the drop tests used in the project qualification. Thus, this paper aims to present and discuss updated recommendations for contacts, material models and general configurations in three benchmarks. These benchmarks represent the phenomena found in numerical simulations of drop trials. Moreover, they are important to obtain an adequate correlation with the lowest possible use of computational resources. From the simulations, it was possible to observe the influence of an analysis carried out in plane strain and another one performed with the complete geometry modeled in scale 1:4 in relation to the computational cost and the precision of the results. A methodology was proposed to calibrate the stiffness and the damping control of the contacts and, mainly, their influence on the behavior of the structure.

    Palavras-Chave: benchmarks; boundary conditions; casks; computerized simulation; damping; finite element method; flexibility; fuel assemblies; fuel elements; mathematical models; nuclear fuels; recommendations; testing; transport

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  • IPEN-DOC 26383

    VIEIRA NETO, ANTONIO S. ; OLIVA, AMAURY M.; SAUER, MARIA E.L.J. ; HUNOLD, MARCOS C.; OLIVEIRA, PATRICIA da S.P.de ; ANDREA, VINICIUS . Knowledge base about risk and safety of nuclear facilities to support analysts and decision makers. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5513-5522.

    Abstract: Epistemic uncertainty (uncertainty related to lack of knowledge), often found in the documentation of nuclear facility engineering projects, can affect the decision-making process of managers and analysts on safety and risk issues. This article conceptualizes the nature of the major uncertainties involved in engineering projects and describes a knowledge base developed in order to gather data and information related to the project of an Open-Pool Light-water Research Rector (OPLRR) and whose purpose is to assist professionals who work in the áreas of safety, design, operation, and maintenance of nuclear facilities. In order to reduce the epistemic uncertainties that may rise in the project, the OPLRR knowledge base is designed to contain a set of information that allows identifying and facilitating the forwarding of solutions to address inconsistencies, and/or pending issues that may exist in the project. In this sense, the information and the documents related to the project are organized in a graphical and hierarchical architecture, allowing the knowledge base users to quickly and easily obtain information regarding the systems, processes, equipment, and components of the Project. Besides that, a set of documents containing descriptions, reliability data and some other important information about the systems and components are specially created to the knowledge base and it is crucial to reduce epistemic uncertainties, once it raises the issues and the inconsistencies of the project, as well as it clarifies the interrelations between the systems, the functioning of the equipment, their failures modes and the consequences of their failures, and some other data, which are not originally contained in the documents of the project.

    Palavras-Chave: data covariances; decision making; design; information dissemination; knowledge base; maintenance; nuclear facilities; personnel; pool type reactors; reactor cores; risk assessment; safety

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  • IPEN-DOC 26382

    SANCHEZ, ANDREA ; CARLUCCIO, THIAGO; SABUNDJIAN, GAIANE . The cross sections obtained by the serpent code and formatting the input data for the PARCS code using the GenPMAXS code. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5503-5512.

    Abstract: The Purdue Advanced Reactor Core Simulator (PARCS) is a computer code that solves the time-dependent two-group neutron diffusion equation in three-dimensional Cartesian geometry using nodal methods to obtain the transient neutron flux distribution. The code is used in the analysis of reactivity-initiated accidents in light-water reactors where spatial effects may be important. It may be run in the stand-alone mode or coupled to other NRC thermal-hydraulic codes such as RELAP5. The PARCS neutron code accepts libraries from HELIOS, TRITON, WIMS, SERPENT, etc., codes, but for some libraries is required special formatting. In the case of the SERPENT code, the GenPMAXS code must be used for the PARCS code to be able to read the cross sections library correctly. This work is part of a study on the PARCS/RELAP5 coupling for analyzing the control rod ejection of the Angra 2 reactor core. For this case, the core cross sections were obtained for 6 different branches varying the fuel temperature, moderator temperature, moderator density, boron concentration and considering rods removed and inserted. After obtaining the cross sections with the code SERPENT 2.1.26, these data were passed by a special formatting realized with the code GenPMAXS v6.2. Since GenPMAXS has several options controlling how to process the cross-sections generated by Serpent, a several doubts arose about the correct use of the code. When the doubts are answered, the file with the input data that will be used for the PARCS / RELAP coupling can be built.

    Palavras-Chave: angra-2 reactor; computerized simulation; control elements; coupling; cross sections; monte carlo method; p codes; reactor cores; rod ejection accidents; s codes

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  • IPEN-DOC 26381

    BORGES, EDUARDO M. ; SABUNDJIAN, GAIANE . Small break loss of coolant accident of 200 cm² in cold leg of primary loop of ANGRA 2 nuclear power reactor evaluation. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5479-5490.

    Abstract: The aim of this paper is evaluated the consequences to ANGRA 2 nuclear power reactor and to identify the flow regimes, the heat transfer modes, and the correlations used by RELAP5/MOD3.2.gama code in ANGRA 2 during the Small-Break Loss-of-Coolant Accident (SBLOCA) with a 200cm2 of rupture area in the cold leg of primary loop. The Chapter 15 of the Final Safety Analysis Report of ANGRA 2 (FSAR-A2) reports this specific kind of accident. The results from this work demonstrated the several flow regimes and heat transfer modes that can be present in the core of ANGRA 2 during the postulated accident. The results obtained for ANGRA 2 nuclear reactor core during the postulated accident were satisfactory when compared with the FSAR-A2. Additionally, the results showed the correct actuation of the ECCS guaranteeing the integrity of the reactor core.

    Palavras-Chave: angra-2 reactor; cladding; eccs; heat transfer; primary coolant circuits; reactor accident simulation; reactor cores; sbloca; steady-state conditions; two-phase flow; void fraction

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  • IPEN-DOC 26380

    BORGES, EDUARDO M. ; SABUNDJIAN, GAIANE ; BRAZ FILHO, FRANCISCO A.; GUIMARÃES, LAMARTINE N.F.. RELAP5 code simulation of the small break loss of coolant accident of 80 cm² in the cold leg of Angra2 primary loop. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5469-5478.

    Abstract: The aim of this paper was to simulate and evaluate the basic design accident of 80 cm² small break loss of coolant accident (SBLOCA) in the cold leg of the primary loop of the Angra2 nuclear power plant. In this simulation, it was verified that the actuation logics of the Angra2 Reactor Protection System (RPS) and the Emergency Core Cooling System (ECCS) used in this simulation worked correctly, maintaining core integrity with acceptable temperatures throughout the event. The results obtained were satisfactory when compared with those presented by the Angra2 Final Safety Analysis Report (FSAR/A2).

    Palavras-Chave: actuators; angra-2 reactor; boundary conditions; primary coolant circuits; r codes; reactor accident simulation; reactor cooling systems; reactor cores; reactor protection systems; safety analysis; sbloca; steady-state conditions; void fraction

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  • IPEN-DOC 26379

    SOARES, HUMBERTO V.; BELCHIOR JUNIOR, ANTONIO ; FREITAS, ROBERTO L.. RELAP5 modeling of a siphon break effect on the Brazilian Multipurpose Reactor. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5443-5456.

    Abstract: This work presents the thermo-hydraulic simulation of the Brazilian Multipurpose Reactor (RMB) using the RELAP5/Mod3 code. The RMB will provide Brazil with a fundamental infrastructure for the national development on activities of the nuclear sector in the areas of social, strategic, industrial applications and scientific and technological development. A RELAP5/Mod3 code model was developed for thermo-hydraulic simulation of the RMB to analyze the phenomenology of the Siphon Breakers device (four flap valves in the cold leg and one open tube for the atmosphere in the hot leg) during a Loss of Coolant Accident (LOCA) at different points in the primary circuit. The Siphon Breaker device is an important passive safety system for research reactors in order to guarantee the water level in the core under accidental conditions. Different simulations were carried out at different location in the Core Cooling System (CCS) of the RMB, for example: LOCA before the CCS pumps with and without pump trip and LOCA after the CCS pumps and the heat exchanger. In all RELAP5/Mod3 code simulations, the Siphon Breaker device's performance after a LOCA was effective to allow enough air to enter the outlet pipe of the CCS in order to break the siphon effect and preventing the pool level from reaching the riser (chimney) and the RMB core discovering. In all cases, the reactor pool level stabilized at about 5.5 m after the end of the LOCA simulation and the fuel elements were kept underwater and cooled.

    Palavras-Chave: cooling systems, fuel elements, loss of coolant, r codes, reactor accident simulation, reactor cores, reactor safety, rmb reactor, thermal hydraulics, transients; cooling systems; fuel elements; loss of coolant; r codes; reactor accident simulation; reactor cores; reactor safety; rmb reactor; thermal hydraulics; transients

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  • IPEN-DOC 26378

    GOMES, DANIEL de S. ; GIOVEDI, CLAUDIA. Combining probabilistic and deterministic methods for accident analysis. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5429-5442.

    Abstract: This study describes a practical method applied to nuclear reactor safety analysis (NRSA), based on an approach so-called best estimate plus uncertainty (BEPU). The innovative analysis approach involves statistical methods integrated with deterministic rules to fuel licensing code (FLC). The goal of NRSA is to improve safety margins in the nuclear reactor operation, which has partially achieved with uncertainty treatment. Previously, BEPU analysis was widely used to study the loss of coolant accident (LOCA), via inclusion in thermal-hydraulic codes (THC). The systems can measure the impact caused by uncertainties spread in core reactors with a coupling of THC and optimization packages. This paper shows the result of applying the UA/SA technique to FRAPCON, joined with DAKOTA toolkit. This integration will offer the probabilistic analysis coupled with empirical rules. A perfect fusion of the concepts permits the exploration of parametric uncertainties and calibration of physical models. We can use the combined utilization of FLC systems and the DAKOTA toolkit to produce sensitivity analysis. The first step in this approach is to identify all uncertainty sources of the physical models, the reactor design, and manufacturing parameters. It is subsequently used into an FLC, such as FRAPCON, as input parameters. The uncertainties usually distributed using the Wilks formula, which determines the number of samples required for unilateral tolerance. According to Wilks' method, it needs 59 data samples to achieve a confidence level of 95%. Results from Wilks formula found via Monte Carlo simulation, which applies to FLC coupled with sensitivity analysis.

    Palavras-Chave: cladding; data covariances; deterministic estimation; f codes; fuel rods; loss of coolant; probabilistic estimation; reactivity; reactor accidents; reactor cores; reactors; safety analysis; sensitivity analysis; transients

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  • IPEN-DOC 26377

    GOMES, DANIEL de S. ; GIOVEDI, CLAUDIA. Comparative analysis of silicon carbide with zirconium-based alloys. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5417-5428.

    Abstract: According to international plans, the nuclear reactor fleet should reduce operational risk and avoid severe accidents. Around the world, there are 450 nuclear power reactors in operation, which supply about 11% of the electricity consumed. There are programs, such as Advanced Fuels Campaign (AFC), that plan to develop a more tolerant fuel system by 2025. These plans follow security concepts that present two options capable of replacing zirconium alloys used as cladding. The better candidates are metallic alloys and ceramic materials. Until the mid-1970s, austenitic steel was the main coating option. Recently, iron-based alloys have become short-term solutions composed of iron-chromium-aluminum (FeCrAl) alloys. However, there are various advantages from using multilayer of silicon carbide (SIC) and ceramic composites. Silicon carbide has higher corrosion resistance, coupled with higher mechanical strength compared to zirconium alloys. Upon steam contact, ceramic cladding mitigates hydrogen buildup, avoiding explosion risk. This study presents a comparison of the thermal and mechanical properties between zirconium alloys and ceramic alternatives. Ceramic materials show desirable mechanical strength, such as high initial crack resistance, stiffness, ultimate strength, impact response, and high corrosion resistance. SIC has a lower neutron cross-section with significant safety margins.

    Palavras-Chave: ceramics; cladding; comparative evaluations; corrosion protection; cross sections; f codes; fuel rods; mechanical properties; nuclear fuels; physical properties; silicon carbides; steady-state conditions; thermal expansion; zirconium alloys

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  • IPEN-DOC 26376

    GABE, CESAR A.; FREIRE, LUCIANO O. ; ANDRADE, DELVONEI A. de . Modeling dynamic scenarios for safety, reliability, availability and maintainability analysis. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5393-5400.

    Abstract: Safety analysis uses probability combinatorial models like fault tree and/or event tree. Such methods have static basic events and do not consider complex scenarios of dynamic reliability, leading to conservative results. Reliability, availability, and maintainability (RAM) analysis using reliability block diagram (RBD) experience the same limitations. Continuous Markov chains model dynamic reliability scenarios but suffer from other limitations like states explosion and restriction of exponential life distribution only. Markov Regenerative Stochastic Petri Nets oblige complex mathematical formalism and still subject to state explosions for large systems. In the design of complex systems, distinct teams make safety and RAM analyses, each one adopting tools better fitting their own needs. Teams using different tools turns obscure the detection of problems and their correction is even harder. This work aims to improve design quality, reduce design conservatism, and ensure consistency by proposing a single and powerful tool to perform any probabilistic analysis. The suggested tool is the Stochastic Colored class of Petri Nets, which supplies hierarchical organization, a set of options for life distributions, dynamic reliability scenarios and simple and easy construction for large systems. This work also proposes more quality rules to assure model consistency. Such method for probabilistic analysis may have the effect of shifting systems design from “redundancy, segregation and independency” approach to “maintainability, maintenance and contingency procedures” approach. By modeling complex human and automated interventional scenarios, this method reduces capital costs and keeps safety and availability of systems.

    Palavras-Chave: availability; computerized simulation; dynamical systems; maintenance; probabilistic estimation; redundancy; reliability; safety analysis; sensitivity analysis; stochastic processes

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  • IPEN-DOC 26375

    BELCHIOR JUNIOR, ANTONIO ; SOARES, HUMBERTO V.; FREITAS, ROBERTO L.. Validation of the RELAP5 code for the simulation of the Siphon Break effect in pool type research reactors. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5383-5392.

    Abstract: In an open pool type reactor, the pool water inventory should act as a heat sink to provide emergency reactor core cooling. In the Brazilian Multipurpose Reactor – RMB, to avoid the loss of pool water inventory, all the Core Cooling System (CCS) lines penetrate at the pool top, far above the reactor core level. However, as most of CCS equipment and lines are located below the reactor core level, in the case of a Loss of Coolant Accident (LOCA), a large amount of pool water could be lost drained by siphon effect. To avoid RMB research reactor core discovering in the case of a LOCA, siphon breakers, that allow CCS line air intake, are installed in the CCS lines in order to stop the reactor pool draining due to siphon effect. As siphon breakers are important passive safety devices, their effectiveness should be verified. Several previous numerical and experimental studies about siphon break effect were found in the literature. Some of them comment about the effectiveness of the siphon breakers based on their air intake area. Others state that one-dimensional thermo-hydraulic system codes such as RELAP5 code would fail when modeling the siphon break effect. This work shows the RELAP5/MOD3.3 code capability in modeling the siphon break effect. A nodalization for RELAP5/MOD3.3 code of a Siphon Breaker Test Facility located at POSTECH University in Korea was developed. Experiments considering several siphon breakers device intake areas were simulated. A very good agreement between numerical and experimental results was obtained. As siphon breakers intake areas decrease, the siphon breaker effectiveness also decreases and more water is drained from the reactor pool. For smaller siphon breaker intake areas, RELAP5/MOD3.3 code showed conservative results, overestimating the reactor pool water losses.

    Palavras-Chave: computerized simulation; loss of coolant; pipes; pool type reactors; r codes; reactor cores; ruptures; safety analysis; tanks; test facilities; test facilities; validation; void fraction

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  • IPEN-DOC 26374

    OLIVEIRA, ELLISON A. ; OLIVEIRA, PATRICIA S.P. ; MATTAR NETO, MIGUEL ; MATURANA, MARCOS C.. Overview of the seismic probabilistic safety assessment applied to a nuclear installation located in a low seismicity zone. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5368-5382.

    Abstract: Permanent concern on the safety of nuclear installations shall be assured in order to maintain the protection of workers, individuals from the public and the environment. Safety analysis methodologies for both approaches, deterministic and probabilistic, have been developed and updated based on operational experience, investigation of past incidents or accidents, and analysis of postulated initiating events. In general terms, the main objectives of a nuclear safety study are the identification of a comprehensive list of accident initiating events, the evaluation of their impact on the installation and the assessment of the total radiological risk resulting from accidents with off-site releases. Among all initiating events and hazards, there are external hazards that continually challenge the safety of a nuclear facility or its nearby area. In particular, seismic events represent a major contributor to the risk of a nuclear facility. Large levels of ground motion induced by earthquakes may be experienced due to the propagation of mechanical waves on the ground, caused by the displacement of tectonic plates. In this context, a seismic hazard analysis can be carried out in order to predict local acceleration levels with the associated uncertainty distribution, allowing an adequate seismic classification of plant structures, systems and components, including installations located in sites with low seismicity. In order to estimate the risk of a nuclear installation concerning accidents induced by seismic events, a Seismic Probabilistic Safety Assessment (Seismic PSA) shall be performed. In this article, a general description of the Seismic PSA methodology is presented, with emphasis on the supporting studies for this assessment. Finally, this study is under the scope of a master degree project at IPEN – CNEN/SP which intends to apply the methodology described in this article to an experimental nuclear installation containing a PWR reactor designed for naval propulsion to be installed in a low seismicity zone in Brazil.

    Palavras-Chave: earthquakes; nuclear facilities; probabilistic estimation; radiation hazards; radiation protection; risk assessment; safety analysis; seismicity

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  • IPEN-DOC 26373

    LEE, SEUNG M. ; LAPA, NELBIA S.; SABUNDJIAN, GAIANE . MELCOR simulation of a severe accident scenario derived from a small break loca in a typical PWR with passive autocatalytic recombiners. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5346-5359.

    Abstract: This work presents the simulation of a severe accident scenario in a referential model of pressurized water reactor, which came about from a rupture of 20cm2 in a cold leg of a reactor cooling system. The simulation was carried out on the MELCOR code using a model elaborated by the Global Research for Safety – Germany, with the passive autocatalytic recombiners implemented in almost every compartment in the containment. The efficacy and effectiveness of this well-known mitigating measure of severe accident management are demonstrated by means of a comparison with the case previously simulated without this measure using the same model. This referential reactor is important and very useful for the independent analysis of severe accidents in the Brazilian Angra 2 nuclear power plant in virtue of the similarity between both of them, so that after some proper modifications on this referential reactor’s model, it could be applied for the study of severe accidents in the other. In this sense, the result presented in this work is to be taken as an important reference for the severe accident analysis of Angra 2.

    Palavras-Chave: boundary conditions; cladding; loss of coolant; m codes; melt-through; pwr type reactors; radiation protection; reactor accident simulation; reactor cooling systems

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  • IPEN-DOC 26372

    LOBO, RAQUEL de M. ; ANDRADE, ARNALDO H.P. de . Advances in the understanding of the mechanisms of iodine-induced SCC cracking in zirconium alloys. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5339-5345.

    Abstract: In pressurized water reactors (PWR) the fuel rod cladding is the first barrier against the spread of fission products. It is therefore essential to guarantee its use in the reactor. Sometimes the production of electricity requires that certain power plants operate in “network monitoring”. The fuel introduced into nuclear power reactors can then undergo so metimes significant power variations. Following a severe reactor power transient, clad failure can occur through a stress corrosion phenomenon (SCC), under the combined action of mechanical stresses and gaseous fission products generated by the fuel pellets. Among those iodine plays a major role, for it may induce SCC in zircaloy. In the early ages of water cooled reactors (PWRs, BWRs or CANDU), series of similar failures took place following sharp startups. Today power increase rates as well as instantaneous local power levels are limited. Indeed, it is well know that cladding failure by iodine induced stress corrosion cracking (I SCC) may occur under pellet cladding interactions (PCI) conditions during power transients in PWRs. In this paper we review the advances in the understanding of these SCC cracking mechanisms of the fuel rod cladding that would then allow better control of the integrity of the clad during the more severe demands related to the operating conditions of th e PWRs.

    Palavras-Chave: cladding; cleavage; computerized tomography; cracking; fuel rods; iodine; nucleation; pitting corrosion; pwr type reactors; slip; stress corrosion; zircaloy 4

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  • IPEN-DOC 26371

    ANDRADE, ARNALDO H.P. de ; MIRANDA, CARLOS A.J. ; LOBO, RAQUEL de M. . Monitoring of the ductile to brittle transition temperature of reactor pressure vessel steels by means of small specimens. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 5322-5338.

    Abstract: Neutron irradiation in nuclear power plants (NPPs) lead to microstructural changes in structural materials which induce a shift of the ductile to brittle transition temperature (DBTT) towards higher temperatures. Monitoring of the DBTT in NPP components receives therefore considerable attention. Small specimen testing techniques are developed for characterizing structural components with a limited amount of materials. One of the most used of these miniature testing is the small punch test (SPT) which is based on disc or square shaped specimens. SPTs may be performed from room to cryogenic temperatures, plotting the absorbed energy until rupture, against the test temperature. A ductile region (high energy) and a brittle region (low energy) with a transition between both zones are usually reported. The transition temperature thus obtained, DBTTSPT, is also related through empirical expressions to the transition temperature obtained in CVN tests, DBTTCVN, or in fracture toughness testing. Linear expressions such as DBTTSPT = α DBTTCVN have been used where α is a material characteristic constant. In all cases, the DBTTSPT temperature is much lower than that obtained in the CVN tests. In this paper, we present a short review of the literature on the determination of the DBTT for nuclear reactors pressure vessels steels by those two techniques analyzing the reason for the difference in their value as mentioned before. In dealing with irradiated materials, is a high priority to limit the exposure of the professional to irradiation. Therefore, the use of miniature specimens receives significant attention in the nuclear community. The high cost of irradiation experiments is a further incentive for using small specimen testing techniques.

    Palavras-Chave: ductile-brittle transitions; embrittlement; fracture properties; irradiation; materials testing; miniaturization; monitoring; reactor vessels; steels

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É possível efetuar a busca de um autor ou um termo em todo o RD, por meio do Buscar no Repositório , isto é, o termo solicitado será localizado em qualquer campo do RD. No entanto esse tipo de pesquisa não é recomendada a não ser que se deseje um resultado amplo e generalizado.

A pesquisa apresentará melhor resultado selecionando um dos filtros disponíveis em Navegar

Os filtros disponíveis em Navegar tais como: Coleções, Ano de publicação, Títulos, Assuntos, Autores, Revista, Tipo de publicação são autoexplicativos. O filtro, Autores IPEN apresenta uma relação com os autores vinculados ao IPEN; o ID Autor IPEN diz respeito ao número único de identificação de cada autor constante no RD e sob o qual estão agrupados todos os seus trabalhos independente das variáveis do seu nome; Tipo de acesso diz respeito à acessibilidade do documento, isto é , sujeito as leis de direitos autorais, ID RT apresenta a relação dos relatórios técnicos, restritos para consulta das comunidades indicadas.

A opção Busca avançada utiliza os conectores da lógica boleana, é o melhor recurso para combinar chaves de busca e obter documentos relevantes à sua pesquisa, utilize os filtros apresentados na caixa de seleção para refinar o resultado de busca. Pode-se adicionar vários filtros a uma mesma busca.

Exemplo:

Buscar os artigos apresentados em um evento internacional de 2015, sobre loss of coolant, do autor Maprelian.

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

Para indexação dos documentos é utilizado o Thesaurus do INIS, especializado na área nuclear e utilizado em todos os países membros da International Atomic Energy Agency – IAEA , por esse motivo, utilize os termos de busca de assunto em inglês; isto não exclui a busca livre por palavras, apenas o resultado pode não ser tão relevante ou pertinente.

95% do RD apresenta o texto completo do documento com livre acesso, para aqueles que apresentam o significa que e o documento está sujeito as leis de direitos autorais, solicita-se nesses casos contatar a Biblioteca do IPEN, bibl@ipen.br .

Ao efetuar a busca por um autor o RD apresentará uma relação de todos os trabalhos depositados no RD. No lado direito da tela são apresentados os coautores com o número de trabalhos produzidos em conjunto bem como os assuntos abordados e os respectivos anos de publicação agrupados.

O RD disponibiliza um quadro estatístico de produtividade, onde é possível visualizar o número dos trabalhos agrupados por tipo de coleção, a medida que estão sendo depositados no RD.

Na página inicial nas referências são sinalizados todos os autores IPEN, ao clicar nesse símbolo será aberta uma nova página correspondente à aquele autor – trata-se da página do pesquisador.

Na página do pesquisador, é possível verificar, as variações do nome, a relação de todos os trabalhos com texto completo bem como um quadro resumo numérico; há links para o Currículo Lattes e o Google Acadêmico ( quando esse for informado).

ATENÇÃO!

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

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

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

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


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