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Artigo IPEN-doc 31024 Experimental and theoretical multichannel study of direct nuclear reactions2024 - SPATAFORA, ALESSANDRO; CARBONE, DIANA; CAPPUZZELLO, CAPPUZZELLO; CAVALLARO, MANUELA; ACOSTA, LUIS E.; AGODI, CLEMENTINA; AMADOR-VALENZUELA, PAULINA; BORELLO-LEWIN, THEREZA; BRISCHETTO, GIUSEPPE A.; CALVO, DANIELA; CHÁVEZ-LOMELÍ, EFRAIN R.; CIRALDO, IRENE; GREGORIO, GIOVANNI de; DELAUNAY, FRANCK; DJAPO, HARIS; EKE, CANEL; FINOCCHIARO, PAOLO; FIRAT, SUNA; FISICHELLA, MARIA; GARGANO, ANGELA; HACISALIHOGLU, AYLIN; LAY, JOSÈ A.; LINARES, ROBERTO; LUBIAN, JESUS; MEDINA, NILBERTO; MORALLES, MAURÍCIO; OLIVEIRA, JOSÈ R. B.; PAKOU, ATHENA; PANDOLA, LUCIANO; PETRASCU, HORIA; SGOUROS, ONOUFRIOS; SILVEIRA, MARCILEI A. G da; SOLAKCI, SELÇUK O.; SOUKERAS, VASILIS; SOULIOTIS, GEORGE A.; TORRESI, DOMENICO; TUDISCO, SALVATORE; YILDIRIM, AYDIN; ZAGATTO, VINICIUS A. B.The search for neutrino-less double beta decay has attracted much interest in the last years due to the extraordinary consequences that could derive from its observation. In the view to provide experimental information on the nuclear matrix elements involved in the expression of neutrino-less double beta decay half-life, the NUMEN project is measuring cross-sections of double charge exchange and other quasi-elastic nuclear reactions using the MAGNEX magnetic spectrometer. In particular, the newly proposed multichannel approach, applied both to the experimental and theoretical analysis, will be discussed.Artigo IPEN-doc 31023 Otimização do núcleo do reator IEA-R1 utilizando o método de enxame de partículas2024 - SANTOS, THIAGO A dos; GENEZINI, FREDERICO A.; STEFANI, GIOVANNI L de; SILVA, MARCELO V.; MOREIRA, LUCILE D.; RESENDE, ANDERSON P.; PALMA, DANIEL A.P.Este trabalho visa o desenvolvimento de um código em FORTRAN 90, para resolver o Problema de Otimização de Recarga (POR), no reator de pesquisa IEA-R1, no Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), em São Paulo, Brasil. O código utiliza o método de Otimização de Enxame de Partículas (PSO), de maneira a se integrar com a metodologia de cálculo do reator atual. A função objetivo busca maximizar o fator de multiplicação efetivo (keff), minimizar o fator de potência de pico (PPF) e atingir a distribuição de fluxo de nêutrons mais uniforme possível. É feita uma comparação com os parâmetros da configuração atual do reator (configuração 260) e uma nova configuração obtida através do código, e este encontra com sucesso soluções que atendem aos requisitos do problema padrão. A nova configuração aumenta a potência de pico (6,93%) e a variância (9,62%), aumenta ligeiramente o fluxo de nêutrons (0,48%), mas reduz marginalmente o keff (0,45%). Entretanto, mesmo com a pequena perda do keff, os ganhos nas demais grandezas são significativos a ponto de mostrar a eficácia do código. Além disso, diminui a temperatura máxima do revestimento de combustível (0,7%), contribuindo para a segurança do reator.Artigo IPEN-doc 31021 Micromachined passive waveguide fabrication with fs laser in Ag-doped GeO2–PbO glasses for photonics2024 - FERNANDES, THIAGO V.; BORDON, CAMILA D.S.; WETTER, NIKLAUS U.; ROSSI, WAGNER de; KASSAB, LUCIANA R.P.This study aims to produce and characterize different dual waveguides using femtosecond (fs) laser irradiation on GeO2-based glass samples. The work is motivated by previous results obtained with rare earth ions doped GeO2 – PbO glass, with and without silver nanoparticles, in which irradiation, with fs laser was successful. The work aims to manufacture different structures such as straight, curved, and Y waveguides (using the double guide configuration) for applications in photonics (resonant rings, beam splitters, among others) in GeO2 – PbO glasses with silver nanoparticles. For both, straight and S curved waveguides, better M2 (beam quality factor) results were found for a distance between the guide walls of 10 μm, when compared to 25 μm. Moreover, among the two different curved guides produced it was also possible to observe better guidance when a larger radius of curvature (20 mm) was used; preliminary tests showed no guiding for 5 mm and 10 mm radius. The highest relative propagation loss was obtained for the S curved waveguide with a 25 μm distance between the guide walls whereas the lowest one was found for the Y shaped waveguide; for this configuration (opening angle of 5° and distance of 620 μm between the two arms) an output power ratio between the left and right arm of 53.9/46.1 showed promising applications for beam splitters.Artigo IPEN-doc 31011 Desempenho mecânico de soldas a ponto em aços avançados para aplicação estrutural automotiva2023 - JESUS, EDILSON R.B. de; ROSSI, JESUALDO L.O aço endurecido por prensagem a quente conhecido como “Press Hardened Steel – PHS”, é um aço de extrema importância para a indústria automotiva. A aplicação desse aço na estrutura de veículos promove o aprimoramento da segurança, redução de massa e menor consumo de combustível. O aumento do uso desse aço, culminou com a necessidade de aprofundar os conhecimentos sobre os processos de união, mais especificamente sobre o processo de soldagem por resistência elétrica conhecido por solda a ponto, do inglês “Resistance Spot Weld – RSW”, que é um dos processos mais usados na construção estrutural automotiva. O objetivo do presente trabalho é a avaliação da solda a ponto autógena do aço PHS 22MnB5 endurecido por tratamento térmico em laboratório, simulando o processo de prensagem a quente comumente aplicado na prática industrial automotiva. Foram feitas duas variações de solda ponto, cada uma com dois parâmetros de soldagem diferentes; em etapa única (parâmetros básicos) e considerando etapas adicionais de pré e pós aquecimento. Mecanicamente as soldas foram avaliadas através de ensaios normalizados pela AWS. Os resultados demonstraram que o desempenho das soldas atende os requisitos mínimos requeridos para o grupo de materiais em que se enquadra o PHS 22MnB5 de acordo com a norma.Artigo IPEN-doc 30971 Tecnologias analíticas instrumentais para a investigação de madeira2024 - ZAMBONI, CIBELE B.; GIOVANNI, DALTON; SILVA, PAULO S.C. da; MOREIRA, EDSON G.; LOBOS, CRISTIAN M.V.; SARRIES, GABRIEL A.; NOGUEIRA, ANA R. de A.; BACCHI, MARCIO A.; MARTINELLI, LUIZ A.; FERNANDES, ELISABETE A. de N.A madeira é uma commodity produzida no Brasil que tem relevância no cenário econômico entretanto o impacto ambiental, devido à expansão das áreas de exploração, tem gerado preocupação com o desmatamento e consequente alterações ambientais, principalmente na região amazônica. Na presente investigação foram testadas três metodologias analíticas instrumentais para autenticação da madeira nativa da Amazônia com base em sua caracterização físico-química. O emprego combinado das técnicas espectrométricas como Fluorescência de Raios X (FRX), bem como análise de compostos orgânicos por Espectroscopia Raman (ER) e Infravermelho (IR) mostraram-se eficiente para uso em metrologia forense, disponibilizando dados que podem ser usados na identificação de madeira nativa, compondo metodologia alternativa para monitoração dos problemas enfrentados na região amazônica (desmatamento, queimadas e invasões ilegais). Além disso, a metodologia estabelecida no presente estudo pode ser aplicada a outras regiões do Brasil, que também produz esse tipo de commodity e enfrentam os mesmos problemas.Artigo IPEN-doc 30967 O desenvolvimento docente sob a ótica de uma ação formativa2024 - SANTANA, DONIZETE dos S.; ALMEIDA, MADISON C. de; EUGENIO, CESAR A.; ANDRADE, DELVONEI A. deO trabalho ora apresentado pautou-se pelo revisionismo do que principais autores escreveram sobre o tema formativo na profissão docente, enfatizando a questão da formação contínua. Variados teóricos pesquisaram como se dá a ação formativa, seus benefícios, seus contextos – no Brasil e no exterior. O artigo possui uma introdução com contextualização, seguida da proposta metodológica; uma revisão da literatura com o cunho qualitativo-exploratório. Os achados históricos, desde o fim do Século XX até o momento atual, traduzem a atualização educacional, voltada para a atenção às questões professor-aluno, dinâmica em sala e objetos ou recursos virtuais em apoio à prática pedagógica. Uma comparação de pensamentos de autores é feita em seguida, seguindo-se a conclusão do estudo.Artigo IPEN-doc 30966 Successful case of multistakeholder partnerships in establishing networks for women in nuclear fields2024 - KALININA-POHL, MARGARITA; MARTIN, OLGA; HAIGHT, KATHERINE; HART-MCGONIGLE, TAYLOR; EVANS, RHONDA; SARKIS, JORGE E. de S.; DUPREEZ, JEANA multistakeholder partnership in nuclear security and nonproliferation programs involves partners from at least three sectors: the public sector, civic society, the private sector and/or academia. Each partner has specialized knowledge, experience, perspectives and resources that can help others achieve their goals and advance their work. This paper highlights several cases of successful collaborations among various stakeholders: national governments, nongovernmental organizations and U.S. national laboratories in promoting diversity, equity, inclusion and accessibility (DEIA) in nuclear security, and the unique value these types of collaborative efforts bring to the community. The paper analyses three cases of effective partnerships in this area: the collaborations between LANL and CNS under DOE NNSA Nuclear Security Women initiative in building two regional networks for women in nuclear security, the partnership between LANL and the World Institute for Nuclear Security to increase transparency and access to information related to DEIA implementation at a national laboratory, and CNS and Nuclear and Energy Research institute (Brazil) collaboration with the support from the Norwegian government, and other U.S. stakeholders to engage women in STEM from Latin America in the discussion of DEI initiatives and practices in the context of nuclear security and nonproliferation. Recommendations and lessons learned from establishing and maintaining such partnerships will also be shared. The paper will conclude with suggestions on how such partnerships can serve as a model for future similar collaborations supporting DEIA in nuclear fields.Artigo IPEN-doc 30965 Nuclearization and environmental justice2024 - CARVALHO, B.R.; RODRIGUES, E.A.This study investigates the adverse impacts of nuclear activities on indigenous populations and identifies strategies for environmental justice. The systematic literature review involved the analysis of 57 articles selected from the Web of Science database. The spatial and historical analysis of nuclear energy reveals a systemic interconnection that ranges from uranium mining to nuclear waste disposal, influencing the global dynamics of supply and demand. The research identified that uranium mining and nuclear waste disposal take place predominantly on indigenous lands, exposing these communities to health risks, environmental degradation and socio-cultural disruption. The United States, Canada and Australia are the main focus of the investigations, with little research in other regions. The study highlights the need for inclusive policies that consider the perspectives of indigenous communities in decision-making processes related to nuclear energy and emphasizes the importance of community engagement and social impact assessment to mitigate negative effects on indigenous populations. The study concludes that although there has been a recent increase in academic interest in these impacts, the amount of research is still limited, especially considering the extent of nuclear operations on indigenous lands.Artigo IPEN-doc 30956 Preliminary study of greenhouse gases near to Santos and São Sebastião ports2024 - ARAUJO, ELAINE C.; ANDRADE, IZABEL da S.; CORREA, THAIS; ANDRADE, THAIS; MACEDO, FERNANDA de M.; BRAGA, ELISABETE S.; ANDRADE, MARIA de F.; LANDULFO, EDUARDOThe carbon biogeochemical cycle in nature involves the atmosphere, ocean, terrestrial and marine biota, and mineral reservoirs, with major fluxes between the atmosphere and both terrestrial biota and ocean waters. Studies link the increase of CO2 and CH4 (GHG) to climate change and anthropogenic activities. Coastal zones have a significant impact on the carbon cycle. This study examines GHG concentrations in estuary systems close to port zones, focusing on Santos and São Sebastião ports in São Paulo, Brazil. Santos Port, the largest in Latin America, and São Sebastião Port, with a petroleum terminal, can be significant contributors of GEE. A preliminary campaign measured CO2 and CH4 for 27 hours using a portable GHG analyzer on the research vessel Albacora from the University of São Paulo's Oceanographic Institute. Results showed promising GHG concentrations, with CO2 levels above 420 ppm near Santos and above 450 ppm near São Sebastião, for methane, the major concentration was ~3 ppm, but in short period of acquisitions, in the major part of traject the level was between ~1.8 - ~1.9 ppm.Artigo IPEN-doc 30947 Assessment of methane concentrations in estuarine regions on the coast of the state of São Paulo2024 - CORREA, THAIS; ANDRADE, IZABEL da S.; MACEDO, FERNANDA de M.; ARAUJO, ELAINE C.; ANDRADE, MARIA de F.; BRAGA, ELISABETE S.; LANDULFO, EDUARDOWe evaluated concentrations of atmospheric CH4, which is considered one of the main gases causing global warming. We observed methane concentrations in the Cananéia-Iguape estuarine system on the southern coast of the state of São Paulo, Brazil and in the Santos estuary, Baixada Santista region, coast of the state of São Paulo, Brazil. The south coast region is widely studied as it presents very well-preserved fauna and flora and thus offers an important background on natural emissions. Data acquisition was carried out by a portable gas analyzer (LGR-ICOSTM GLA131), this equipment has a high sensitivity in detecting the gases under study and was placed on board the research vessels Albacora and Alpha Delphini owned by the Institute of Oceanography at the University of São Paulo in campaigns that were carried out between 2021 and 2023 in specific periods. The concentrations observed during the exploratory campaigns in the estuaries on the coast of the State of São Paulo (Iguape Cananéia Estuarine-Lagunar Complex and Santos Estuary) behaved as described in the literature, regions with greater anthropic impact present higher values of methane concentrations in the atmosphere, low-impact regions have lower methane concentrations.Artigo IPEN-doc 30945 Investigating methane emissions from Landfill in the Metropolitan Region of São Paulo2024 - SILVA, THAIS A. da; ARAUJO, ELAINE C.; ANDRADE, IZABEL da S.; ANDRADE, MARIA de F.; LANDULFO, EDUARDOThis research addresses the escalating global levels of atmospheric methane, emphasizing the critical need for understanding its sources and behavior. Landfills are identified as methane super emitters, because its rates range from 1,000 to 3,000 kg/h. Focusing on the Landfill in the district of São Mateus, in the city of São Paulo, the study aims to investigate the significance of landfills in the rising methane levels, emphasizing the impact of super emitters and methane hotspots. Field campaigns conducted on February 15th and April 06th, 2023, utilized a portable greenhouse gas analyzer (ABB) to measure methane concentrations. Meteorological parameters from ERA5 and the AERMOD Modeling System were used for a comprehensive analysis. The results highlight elevated methane concentrations around the Landfill, emphasizing its role as a significant methane super emitter. The study underscores the importance of such analyses in understanding the impact of landfills on atmospheric methane levels.Artigo IPEN-doc 30909 ZnO-DSSC2024 - SERNA, M.M.; GALEGO, E.; FARIA, R.N.; SAKATA, S.K.In the search for clean energy generation, solar energy has so far occupied the leading role; among the various factors that favor it are the possibility of generating energy on the surface of the planet and in outer space, in addition to the small environmental impact of generation plants and the possibilities of generation in urban environments. Within the different types of solar cells, dye-sensitized solar cells (DSSC) promise to revolutionize energy generation through their application as the external coating of large buildings. In the manufacture of this type of cell, non-toxic and low-cost materials are used; however the maximum conversion efficiency is still low when compared to silicon cells. One of the factors that contribute to the decrease in efficiency is the process of recombination of the photogenerated electron with the electrolyte. In the most common type of DSSC that uses a glass substrate coated with SnO2:F (FTO) to manufacture the photoanode, this surface acts as a recombination site. The objective of this work was to study the addition of a graphene layer between the FTO and the semiconductor oxide film in order to minimize recombination processes through the insertion of a new energy level. The deposition of reduced graphene oxide (rGO) was carried out by dip coating with different numbers of deposition cycles (0, 2, 5, 10 cycles). A ZnO paste was deposited on this film using the doctor blade technique with a green thickness of 50 µm. The assembly was heat treated at 450 °C for 1 h, aiming to reduce rGO to graphene and aggregate ZnO into a porous structure. The set was sensitized with the dye N719 and the solar cells were assembled with an FTO/Pt counter electrode and an electrolyte with the iodide/triodide redox couple. The electrical parameters were obtained from the survey of IV curves in a solar simulator with a power of 100 mW cm-2 and air mass 1.5. The morphology of the photoanode was studied by scanning electron microscopy (SEM). The micrographs obtained by SEM show that a porous ZnO film was formed with an average thickness of 25 µm. The cell efficiency increased with the increase in the number of dip coating cycles from 0.39% without rGO to 0.72% with 10 cycles of rGO deposition. The variation in the fill factor was less than 10%. The series resistance values are of the same order of magnitude, indicating that the rGO did not act to increase the conductivity at the rGO/FTO interface, whereas the series resistance values will increase with the increase in the number of cycles, which allows us to conclude that the rGO acts as a blocking layer preventing the regeneration of the electrolyte with the photogenerated electron.Artigo IPEN-doc 30783 Estudo das propriedades mecânicas da liga de alumínio AA80112024 - CARDOSO, ANTONIO M.; SOUZA, CAIQUE M.P. de; OLIVEIRA, REBECA R. de; SANTOS, VINICIUS T. dos; SERIACOPI, VANESSA; OLIVEIRA, RENE R. de; SILVA JUNIOR, WILSON C. daAs propriedades do alumínio, como baixo peso específico e boa resistência mecânica de suas ligas, o tornam atraente para diversas aplicações, em uma indústria que cada vez mais avança tecnologicamente e visa desenvolver novos materiais e novas aplicações das ligas existentes, visando à redução de custos. As chapas da liga de alumínio AA 8011 possuem duas propriedades mecânicas que são importantes em produtos laminados, trata-se da combinação da alta conformabilidade com boa resistência mecânica. Essas propriedades aumentam a aplicação da liga em diversas áreas como embalagens alimentícias, utensílios domésticos, componentes da indústria automotiva e outros. Neste estudo, a liga de alumínio AA 8011 foi laminada em diferentes graus de deformação, variando entre 9,75% e 25,4% e cinco corpos de prova sofreram recozimento em cinco temperaturas diferentes, que variaram de 100°C a 320°C, por 1 hora. Os corpos de prova foram submetidos a ensaio de tração para a realizar o levantamento dos valores das propriedades mecânicas, determinação da curva de encruamento e de recozimento, e caracterização microestrutural. Os resultados obtidos apresentam valores de tenacidade média de 72,5 J.m-3, módulo de resiliência 2,09 J.m-3, valores de dureza, microestruturas, em conjunto com as curvas de encruamento e recozimento, que apresentaram parâmetros que permitem vislumbrar novas possibilidades de aplicação desta liga.Artigo IPEN-doc 30711 Preliminary study to propose a PWR Small Modular Reactor for a Nuclear Powered Submarine2024 - TAVARES, THAIS D.; SABUNDJIAN, GAIANEArtigo IPEN-doc 30710 Challenges related to communicating with the public about radioactive waste disposal2024 - BUENO, L.; VICENTE, R.Artigo IPEN-doc 30709 Chemical characterization of oyster shells of the species Crassostrea mangle and Crassostrea gigas2024 - ALBUQUERQUE, CAROLINE R.; SILVA, PAULO S.C. da; TORRECILHA, JEFFERSON K.; LINHARES, HORACIO M.S.M.; MELO, CLAUDIO M.R. deArtigo IPEN-doc 30708 Pb and Cd assessment in three catfish species from an estuarine ecosystem in São Paulo State, Brazil2024 - MIRANDA, LARISSA Y.; HORTELLANI, MARCOS A.; SARKIS, JORGE E.S.; AZEVEDO, JULIANA S.Artigo IPEN-doc 30707 Single nanoparticle ICP-MS for characterization of gold nanoparticles2024 - GERALDES, ADRIANA N.; HORTELLANI, MARCO A.; SARKIS, JORGE E. de S.Artigo IPEN-doc 30706 Comparison between methods for detecting bacterial concentration for the determination of bacterial radioresistance value2024 - BARNA, F.S.; DIAS, G.; VIEIRA, D.P.; MATHOR, M.B.Artigo IPEN-doc 30705 Sustainable synthesis of cobalt nanoparticles for supercapacitors application2024 - DUARTE, M.; FOO, CHOO T.; OLIVEIRA, K.; SILVA, D.V. da; FARIA JUNIOR, R.N.; SAKATA, S.K.