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  • IPEN-DOC 27678

    CERAVOLO, FLÁVIO E. ; ROCHA, MARCELO da S. ; ANDRADE, DELVONEI . CFD simulation of isothermal upward two-phase flow in a vertical tube of annular section. In: BRAZILIAN CONGRESS OF THERMAL SCIENCES AND ENGINEERING, 18th, November 16-20, 2020, Online. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2020.

    Abstract: This work presents a simulation of a vertical, upward, isothermal two-phase flow of air bubbles and water in an annular channel applying a Computational Fluid Dynamics (CFD) code. The simulation considers an Eulerian frame, with a two-fluid model, specific correlations for turbulence modeling, and bubble-induced turbulence effects. The work intends to assess the accuracy of the code by comparing the simulation results with experimental data obtained from the literature. The annular channel has an equivalent hydraulic diameter of 19.1 mm, where the outer pipe has an internal diameter of 38.1 mm, the inner cylinder 19.1 mm, and a total length of 1900 mm. The void fraction distribution, taken radially to the flow section, is the main parameter analyzed besides interfacial area concentration (IAC), interfacial gas velocity, and bubble diameters distribution. The numerical models applied in this work demonstrate satisfactory agreement with the experimental data but indicate the need for further improvement in the phase interaction models.

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  • IPEN-DOC 27620

    ABE, ALFREDO ; SILVA, ANTONIO T. e ; GIOVEDI, CLAUDIA; MELO, CAIO; GOMES, DANIEL de S. ; MUNIZ, RAFAEL R.. The IPEN/CNEN contribution to IAEA FUMAC benchmark using modified fuel performance code based on stainless steel as cladding under steady state, transient 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... Vienna, Austria: International Atomic Energy Agency, 2020. p. 1-9.

    Abstract: The IPEN/CNEN (Brazil) participated in IAEA Coordinated Research Project on Fuel Modeling in Accident Conditions (FUMAC) among others 18 countries (Argentina, Belgium, Bulgaria, China, Czech Republic, Finland, France, Germany, Hungary, Italy, Japan, Norway, Republic of Korea , Russian Federation , Spain , Sweden , Ukraine and United States of America), which aim was focused in modelling, predicting and improving the understanding of the behaviour of nuclear fuel under accident conditions in order to better understanding and enhanced safety of nuclear fuel. A serie of LOCA (Loss of Coolant Accident) experiments data were made available for the participants to perform simulation using their fuel performance codes and the outcome gives an idea about fuel codes limitation considering LOCA simulation and possible improvement needed in the existing models related to LOCA condition.The IPEN/CNEN (BRAZIL) proposal for FUMAC-CRP was to modify existing fuel performance codes (FRAPCON and FRAPTRAN) considering stainless steel as cladding material and perform a simulation comparing to zircaloy cladding performance under steady state and accident condition. The HALDEN LOCA Experiments (IFA 650-9, IFA-650-10 and IFA-650-11) were selected and modeled to perform the LOCA accident simulation considering the original cladding (zircaloy) and compared to stainless steel cladding.

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  • IPEN-DOC 27616

    PERROTTA, J.A. ; CARVALHO, E.F.U. ; DURAZZO, M. ; SANTOS, L.R. dos ; BAPTISTA, J.A. ; SILVA, J.E.R. da ; JUNQUEIRA, F.C. ; SANTOS, ADIMIR dos ; ARAUJO, A.M.V. de; TOMAZELLI, I.. The RMB project: fuel cycle management. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: ADDRESSING CHALLENGES AND OPPORTUNITIES TO ENSURE EFFECTIVENESS AND SUSTAINABILITY, November 25-29, 2019, Buenos Aires, Argentina. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2020.

    Abstract: The Brazilian Nuclear Energy Commission (CNEN) decided to construct a new research reactor, named RMB (Brazilian Multipurpose Reactor). It is a 30 MW open pool-type research reactor using low enriched uranium fuel, and several associated facilities and laboratories. To establish an infrastructure for producing fuel assemblies for RMB operation and uranium targets for Mo-99 production, the RMB technical secretary has developed a coordinated project for the fuel cycle management system, putting together the fuel technology actors in Brazil. The goals of this coordinated project were: (i) to have a centrifuge cascade enriching uranium up to 20 wt% with the capacity to supply RMB yearly needs; (ii) to upgraded the CNEN existing infrastructure to produce nuclear fuel assemblies and uranium targets for the RMB yearly needs; (iii) to produce a set of fuel assemblies for a real RMB mockup core at the IPEN/MB-01 Critical Facility of CNEN. The RMB project design incorporates structures, systems and components (SSC) for interim storage of spent fuels for the hole plant lifetime. This paper presents details of the coordinated project that gives support and sustainability to the RMB fuel cycle supply and the spent fuel SSC designed.

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  • IPEN-DOC 27615

    PERROTTA, J.A. ; SOARES, A.J. ; LIM, M.L.; IBELLI, M.C.; BARRERA, M.; KOROCHINSKY, S.; GAMBETTA, M.. The RMB project: technical and management development status. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: ADDRESSING CHALLENGES AND OPPORTUNITIES TO ENSURE EFFECTIVENESS AND SUSTAINABILITY, November 25-29, 2019, Buenos Aires, Argentina. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2020.

    Abstract: The Brazilian Nuclear Energy Commission (CNEN) decided to construct a new research reactor, named RMB (Brazilian Multipurpose Reactor). This reactor will be part of a new nuclear research center, to be built on a site about 100 kilometers from São Paulo city, in the southeast part of Brazil. It is a 30 MW open pool-type research reactor using low enriched uranium fuel, and several associated facilities and laboratories in order to produce radioisotopes for medical and industrial use; to use thermal and cold neutron beams in scientific and technological research; to perform neutron activation analysis; and to perform materials and fuel irradiation tests. This project started in September 2008 and is nowadays at the development stage before construction. This article presents updated information on the technical design and the safety features regarding the reactor and the overall installation. It also presents an update on the nowadays overall development status of the RMB project and lessons learned related to the complexity of the project management.

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  • IPEN-DOC 27614

    BITELLI, U.D. ; COELHO, P.R.P. ; FERREIRA, P.S.B. ; ALVES, M.A.P.; SILVA, A.A. ; SANTOS, A. ; DINIZ, R. ; JEREZ, R. ; FUGA, R. ; FANARO, L.C.C.B. ; KURAMOTO, R. ; ABE, A. ; LAMBIASI, B. ; GIADA, M.; FER, N.; MARTINS, F. ; MURA, L. ; SANTOS, D.F. ; AREDES, V. ; MAEDA, R.; GONNELI, E. ; SILVA, A.F.P.; PURGATO, R. ; GONÇALVES, L.B. ; SILVA, G.S.A. ; PINTO, L. ; SOUZA, G.. Main experiments performed at the IPEN/MB-01 RR using UO2 fuel rods core. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: ADDRESSING CHALLENGES AND OPPORTUNITIES TO ENSURE EFFECTIVENESS AND SUSTAINABILITY, November 25-29, 2019, Buenos Aires, Argentina. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2020.

    Abstract: This paper aims to show the main experimental utilization of the IPEN/MB-01 zero power reactor during the last 30 years with 3663 operations cycles. The IPEN/MB-01 reactor it was mainly used to validation of calculation methodology used in nuclear reactor cores design.

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  • IPEN-DOC 27613

    PERROTTA, J.A. . Considerations and challenges of research reactor management. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: ADDRESSING CHALLENGES AND OPPORTUNITIES TO ENSURE EFFECTIVENESS AND SUSTAINABILITY, November 25-29, 2019, Buenos Aires, Argentina. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2020.

    Abstract: Technically, nuclear reactors are equipment were neutron chain reactions of fissile material are safely controlled. Particularly, Research Reactors (RR) use the produced neutrons to a variety of objectives in science, technology, innovation, education, and direct products to society as, for example, the radioisotopes for nuclear medicine. Management is a fundamental aspect to the mission success of a RR and essential to its sustainability and effectiveness. As higher the neutron flux and the RR utilization, more complex are the management actions required to the installation, and their out-installation interfaces as well. Nevertheless, basic management requirements are still necessary to low neutron flux RR, for example, a critical facility. There are many important areas to be considered in RR management as organizational structure, operation, utilization, safety, fuel management, waste management, accessibility and security, human resources development, and financial resources among others. This paper resumes the author invited oral presentation that covers relevant aspects of RR management. Examples are given, based on the author’s experience, related to RRs fulfilling their planned missions and, particularly, related to the development and installation of a new RR project.

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  • IPEN-DOC 27612

    GENEZINI, F.A. ; FERNANDES, A.J. ; ZAHN, G.S. . The IEA-R1 62 years of operation: experiences and lessons learned. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: ADDRESSING CHALLENGES AND OPPORTUNITIES TO ENSURE EFFECTIVENESS AND SUSTAINABILITY, November 25-29, 2019, Buenos Aires, Argentina. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2020.

    Abstract: Early in 1956, the Atomic Energy Institute (IEA, from the acronym in portuguese) was founded with the aim of installing the nuclear research reactor purchased from the American company Babcock & Wilcox in the framework of the “Atoms for Peace” program. The start-up was on September 16, 1957, where the first criticality in the Southern hemisphere was achieved. The IEA-R1 is a pool type, light water cooled and moderated, beryllium and graphite reflected research reactor. Although designed to operate continuously at up to 5 MW, it operated at 2 MW for 40 years and only rather recently started operating at 5 MW. This year IEA-R1 completed 62 years of operation. The reactor is the core of the Nuclear and Energy Research Institute – IPEN (former IEA) – with its laboratories working for radiopharmaceutical applications, in the areas of radiological protection, nuclear fuel cycle, nuclear engineering, and radiation applications among others. Throughout this period it underwent several reforms, renovations and changes of management. In 2000 an Integrated Management System (IMS) has been structured, based on ISO-9001, in order to keep the operation safe, which implied certain procedures together with a continuous modernization program, and to comply with the regulatory requirements at the date as well. The first certification dates to 2002 and since then the reactor has been successfully renewing its ISO certification. The history, experiences and lessons learned during the 62 years of the IEA-R1 operation are described and shared in this paper.

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  • IPEN-DOC 27611

    DINIZ, RAPHAEL E. ; OLIVEIRA, ALDO R. de ; TERRA, ADRIANA C. ; POTIENS, MARIA da P.A. . Avaliação do desempenho do sistema de referência para a calibração de medidores de radiação. In: CONGRESSO DE QUALIDADE EM METROLOGIA, LABORATÓRIOS E INDÚSTRIA, 17., 30 de novembro - 2 de dezembro, 2020, Online. Anais... São Paulo, SP: Rede Metrológica do Estado de São Paulo, 2020. p. 1-7.

    Abstract: O Laboratório de Calibração do Instituto de Pesquisas Energéticas e Nucleares, LCI, atua a mais de 30 anos calibrando instrumentos medidores de radiação aplicados em procedimentos de proteção radiológica, radioterapia e radiodiagnóstico, pertencentes a hospitais, indústrias, clínicas e outros usuários. No ano de 2002, foi estabelecido um Sistema da Qualidade no LCI que desde então tem passado por auditorias internas anualmente. No ano de 2017 o laboratório conseguiu alcançar a acreditação de acordo com a norma ISO 17025 para o escopo “calibração de instrumentos de medição em proteção radiológica: medidor de taxa e de equivalente de dose ambiente”. O sistema utilizado como referência para estas calibrações é composto por uma câmara de ionização esférica marca PTW, com volume de 1L, acoplada a um eletrômetro PTW, modelo UNIDOS. Este sistema tem passado por calibrações periódicas com rastreabilidade ao Laboratório Nacional de Metrologia das Radiações Ionizantes. Para garantir um bom desempenho nas medicões realizadas com este sistema, foi implantado um programa de controle de qualidade com testes de repetibilidade, corrente de fuga e estabilidade ao longo do tempo. Foi utilizada uma fonte de controle de Sr-90 também da PTW. Neste trabalho é demonstrado o desempenho dos sistema de referência ao longo de 18 anos. Foram realizados em torno de 100 testes de controle de qualidade. Os resultados obtidos foram comparados com o gráfico histórico de estabilidade do sistema. É permitida uma variação de até 2% do valor de referência determinado anteriormente.

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  • IPEN-DOC 27610

    SARAU, SARA T. ; RODRIGUES JUNIOR, ORLANDO ; POTIENS, MARIA da P.A. . Instrução Normativa n° 54 da ANVISA e a importância dos testes de aceitação e controle de qualidade em serviços mamográficos. In: CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 7., 23-25 de novembro, 2020, Online. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2020. p. 1-12.

    Abstract: Considerando que em 26 de dezembro de 2019 a ANVISA publicou a RDC n° 330 para serviços de radiologia diagnóstica e intervencionista e a Instrução Normativa n° 54 para sistemas de mamografia, neste trabalho realizou-se uma análise do estabelecido para testes de dosimetria da mama e de camada semi-redutora e um estudo comparativo de valores obtidos em quatro mamógrafos digitais direto publicados na literatura e os valores de referência e de tolerância apresentados na IN-54. Os resultados reforçam a importância da elaboração de um programa de controle de qualidade e da análise conjunta dos resultados obtidos em todos os testes.

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  • IPEN-DOC 27609

    XAVIER FILHO, JOEL M. ; SILVEIRA, IURY S. ; CALDAS, LINDA V.E. . Espectros de feixes padrões de radiação X nas qualidades de radiodiagnóstico e mamografia a partir de simulações Monte Carlo. In: CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 7., 23-25 de novembro, 2020, Online. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2020. p. 1-9.

    Abstract: Foram simulados os seis feixes RQR 5, 8, M1, M2, M3 e M4 descritos na norma TRS-457 (IAEA) utilizando o código de Monte Carlo EGSnrc. Foram realizadas simulações computacionais de um tubo de raios X para a obtenção de seus espectros utilizando o software BEAMnrc. As curvas de atenuação para cada espectro foram obtidas com o aplicativo egs_kerma. Por meio das 1ª e 2ª camadas semi-redutoras, dos coeficientes de homogeneidade e das energias médias foi possível determinar a qualidade de cada um dos feixes simulados. Todos os parâmetros de qualidade foram próximos aos estabelecidos na norma TRS-457 (IAEA).

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  • IPEN-DOC 27550

    ALMEIDA, JORGE V. de; SILVA, EDUARDO C. da; MOSSO, MARBEY M.; SARTORI, CARLOS A.F. . Virtual magnetic TL-based channel modeling of SWIPT systems assisted by MTMs. In: MATOS, LENI J. de (Ed.) SIMPÓSIO BRASILEIRO DE MICRO-ONDAS E OPTOELETRÔNICA, 19.; CONGRESSO BRASILEIRO DE ELETROMAGNETISMO, 14., 8-12 de novembro, 2020, Online. Anais... São Caetano do Sul, SP: SBMO, 2020. p. 674-678.

    Abstract: This paper describes a general methodology for the description of inductive power and data transfer based on virtual magnetic transmission-lines (VMGTLs). This approach presents a better physical insight on the channel behavior since the model correctly preserves the energy flow between the transmitting and receiving coils. Particularly, the virtual-TL analogy clarifies the mechanism of transmission gain improvement between any two coils assisted by MTM lenses. Based on the results of this work, these lenses do not enhance the magnetic coupling between the drivers, as usually claimed, but create conditions to propagating near-field modes to increase their power transfer. This approach also reveals that MTMs could be employed not only for the increasing of power transfer but also for enlarging the inductive channel bandwidth.

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  • IPEN-DOC 27549

    SANTOS, DANIEL de P. dos; SARTORI, CARLOS A.F. . Análise comparativa de métodos ativos de redução de sobretensão em motores por superposição de pulsos. In: MATOS, LENI J. de (Ed.) SIMPÓSIO BRASILEIRO DE MICRO-ONDAS E OPTOELETRÔNICA, 19.; CONGRESSO BRASILEIRO DE ELETROMAGNETISMO, 14., 8-12 de novembro, 2020, Online. Anais... São Caetano do Sul, SP: SBMO, 2020. p. 791-795.

    Abstract: Sobretensão em motores elétricos acionados por conversores estáticos de frequência representam grande risco à integridade do equipamento e se intensificam à medida que tais conversores aperfeiçoam sua velocidade de chaveamento. Os métodos ativos de redução de sobretensão por superposição de pulsos se utilizam dos próprios conversores de frequência para suprimir ou minimizar os pulsos refletidos através do cabo de acionamento do motor, que geram a sobretensão. Esse artigo explora alguns desses métodos em termos de eficácia, flexibilidade e robustez e faz uma análise comparativa destes. Também são realizadas comparações entre sistemas de acionamento dotados de IGBTs de silício e de MOSFETs de carbeto de silício.

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  • IPEN-DOC 27538

    GUANABARA JUNIOR, PAULO; NOGUEIRA, ALESSANDRO F.; SAMAD, RICARDO E. ; ROSSI, WAGNER de . Study of ablation on surfaces of zircaloy Z-4 irradiated with femtosecond laser. 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 use of ultrashort femtosecond laser pulses is an alternative for micro machining on metal surfaces, with several industrial applications, in such areas as aeronautics, aerospace, naval, nuclear, among others, where there is growing concern about service reliability. Thus, markings for traceability purposes should ensure the integrity of the metal as well as allow reading of the marked characters, whether automated or not. In this work, micro machining of zircaloy Z 4 surfaces using femtosecond laser was performed aiming at the knowledge of the ablation threshold and Scanning Electron Microscopy (SEM) analysis in different images. Obtained from micro machined traces, energy fluence parameters and laser pulse overlap. The amount of ablated material in this femtosecond laser micro machining is negligible, which contributes to ensuring that there is no mi crostructural damage. Such a process resulted in different images, which characterize that there are different optical properties because of the parameters change.

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  • IPEN-DOC 25553

    PIERETTI, EURICO F. ; ANTUNES, RENATO A.; NEVES, MAURICIO D.M. das . Tribological evaluation of an optical fiber laser marked stainless steel for biomedical applications. In: CONGRESSO BRASILEIRO DE ENGENHARIA BIOMEDICA, 26., 21-25 de outubro, 2018, Búzios, RJ. Anais... 2018. p. 1-6.

    Abstract: The effect of laser marking process on the tribological behaviour of ISO 5832-1 austenitic stainless steel (SS) on the friction coefficient and wear volume using ball-cratering wear tests was evaluated in this work. The laser marking process was carried out with a nanosecond optical fiber ytterbium laser at four different pulse frequencies. For comparison reasons, surfaces without laser treatments were also evaluated. A phosphate buffer solution (PBS) was used as lubricant. The wear tests were carried out during 10 min with PBS drip, solid spheres of AISI 316L SS with 1 inch in diameter and of 52-100 chrome steel, with 2 mm in diameter, were used as counter-bodies. The results indicated that the tribological behaviour is influenced by the laser marking process parameters used, and the wear rate is dependent of the normal force and the type of sphere.

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  • IPEN-DOC 27536

    GONÇALVES, MARIA C.C.; MERGULHAO, MARCELLO V. ; STOETERAU, RODRIGO L.; BATALHA, GILMAR F.; NEVES, MAURICIO D.M. . Análise de amostras da liga de titânio Ti6Al4V impressas por FSL para ensaios de microfresamento / Selective Laser Melting printed Ti6Al4V titanium alloy samples analysis for micro milling tests. 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 fabricação de peças metálicas via impressão 3D tem ganhado destaque pela sua eficácia na manufatura de geometrias complexas e com pouco consumo de material. Uma das estratégias de sinterização utilizadas para impressão 3D é a Fusão Seletiva a Laser (FSL), que consiste na completa fusão dos pós metálicos por meio de um feixe laser. As peças obtidas por esse processo apresentam uma superfície com ondulações periódicas e anisotropias relacionadas à direção da sinterização. No entanto, o efeito dessa ondulação e da anisotropia das peças nas suas propriedades mecânicas e na sua usinabilidade é pouco conhecido. Visto isso, este trabalho visa examinar amostras da liga de titânio Ti6Al4V impressas por FSL, mediante análises de dureza, rugosidade e por microscópio óptico para ensaios de microfresamento.

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  • IPEN-DOC 27470

    KIBRIT, E. ; AQUINO, A.R. . Sustainability management system model for operating organisations of nuclear research reactors. In: EUROPEAN RESEARCH REACTOR CONFERENCE, October 12-15, 2020, Online. Proceedings... Brussels, Belgium: European Nuclear Society, 2020.

    Abstract: United Nations’ 2030 Agenda for Sustainable Development establishes 17 Sustainable Development Goals (SDGs). Nuclear and isotopic techniques contribute directly to achieving the SDGs related to energy, human health, food production, water management and environmental protection. This paper proposes a sustainability management system model for operating organisations of nuclear research reactors, supported by four sustainability pillars: institutional, economic, environmental and social. Each pillar of sustainability is formed by categories of indicators found in bibliographic references and validated by nuclear and sustainability academic experts, by using Delphi method. The management system model proposed has a high-level structure based on standards established by International Organisation for Standardization (ISO), considers safety requirements of International Atomic Energy Agency (IAEA) and corporate sustainability requirements found in bibliographic references. Stakeholders’ requirements and expectations are inputs of the management system. The focus of the management system is nuclear safety and the organisation's commitment to sustainable development. A method for validating the sustainability management system, a sustainable development matrix to assess the maturity of sustainability management over time, and a sustainable value model, which evaluates the path taken by the organisation towards sustainable development, are tools that support the management system proposed. The management system outputs are management decisions that comply with organisation's policy, objectives and processes; products that meet stakeholders' requirements and expectations; and a Sustainability Report that contains sustainability indicators addressed by institutional, economic, environmental and social dimensions.

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  • IPEN-DOC 27467

    NEVES, R.A.L.; GATTI, L.V. ; BASSO, L.S.; MARANI, L.; CRISPIM, S.P.; CORREIA, C.S.C. ; DOMINGUES, L.G. ; PAUL, D.; SCHEEREN, B.; ADNEW, G.; ROCKMANN, T.; PETERS, W.. Measuring stables isotopes of CO2 (13C and 17,18O) in vertical profiles over the Amazon. In: CROTWELL, ANDREW (Ed.); LEE, HAEYOUNG (Ed.); STEINBACHER, MARTIN (Ed.) WMO/IAEA MEETING ON CARBON DIOXIDE, OTHER GREENHOUSE GASES AND RELATED MEASUREMENT TECHNIQUES, 20th, September 2-5, 2019, Jeju Island, South Korea. Proceedings... Geneva, Switzerland: World Meteorological Organization, 2020. p. 129-132. (GAW Report 255).

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  • IPEN-DOC 27466

    MARANI, L.; BORGES, V.F. ; GATTI, L.V. ; DOMINGUES, L.G. ; CORREIA, C.S.C. ; BASSO, L.S.; SANTOS, R.S. dos ; CRISPIM, S.P.; NEVES, R.A.L.; GLOOR, M.; MILLER, J.B.. Background concentrations of CO2, CO and N2O in Brazilian coast. In: CROTWELL, ANDREW (Ed.); LEE, HAEYOUNG (Ed.); STEINBACHER, MARTIN (Ed.) WMO/IAEA MEETING ON CARBON DIOXIDE, OTHER GREENHOUSE GASES AND RELATED MEASUREMENT TECHNIQUES, 20th, September 2-5, 2019, Jeju Island, South Korea. Proceedings... Geneva, Switzerland: World Meteorological Organization, 2020. p. 125-128. (GAW Report 255).

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  • IPEN-DOC 27465

    GATTI, L.V. ; MILLER, J.B.; GLOOR, M.; DOMINGUES, L.G. ; CORREIA, C.S.C. ; BASSO, L.; MARANI, L.; CASSOL, H.L.G.; TEJADA, G.; BORGES, V.F. ; PETERS, W.; CRISPIM, S.P.; LOPES, R.; RIBEIRO, M.M.; MORAIS, C.S.; AQUINO, C.A.B.. Measurement program of GHG vertical profiles at Amazon. In: CROTWELL, ANDREW (Ed.); LEE, HAEYOUNG (Ed.); STEINBACHER, MARTIN (Ed.) WMO/IAEA MEETING ON CARBON DIOXIDE, OTHER GREENHOUSE GASES AND RELATED MEASUREMENT TECHNIQUES, 20th, September 2-5, 2019, Jeju Island, South Korea. Proceedings... Geneva, Switzerland: World Meteorological Organization, 2020. p. 111-115. (GAW Report 255).

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  • IPEN-DOC 27464

    BASSO, L.S.; SANTOS, R.S.; BORGES, V.F. ; GATTI, L.V. ; DOMINGUES, L.G. ; CORREIA, C.S.C. ; MARANI, L.; CRISPIM, S.P.; NEVES, R.A.L.; GLOOR, M.; MILLER, J.B.. Study of long term SF6 mole fractions in Amazon and Brazilian coast. In: CROTWELL, ANDREW (Ed.); LEE, HAEYOUNG (Ed.); STEINBACHER, MARTIN (Ed.) WMO/IAEA MEETING ON CARBON DIOXIDE, OTHER GREENHOUSE GASES AND RELATED MEASUREMENT TECHNIQUES, 20th, September 2-5, 2019, Jeju Island, South Korea. Proceedings... Geneva, Switzerland: World Meteorological Organization, 2020. p. 107-110. (GAW Report 255).

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  • IPEN-DOC 27463

    BASSO, L.S.; BORGES, V.F. ; GATTI, L.V. ; MARANI, L.; MORAIS, C.S.; CORREIA, C.S.C. ; DOMINGUES, L.G. ; NEVES, R.A.L.; CRISPIM, S.P.; GLOOR, M.; MILLER, J.B.. Long term CH4 measurements in Amazon and Brazilian coast. In: CROTWELL, ANDREW (Ed.); LEE, HAEYOUNG (Ed.); STEINBACHER, MARTIN (Ed.) WMO/IAEA MEETING ON CARBON DIOXIDE, OTHER GREENHOUSE GASES AND RELATED MEASUREMENT TECHNIQUES, 20th, September 2-5, 2019, Jeju Island. Proceedings... Geneva, Switzerland: World Meteorological Organization, 2020. p. 103-106. (GAW Report 255).

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  • IPEN-DOC 27462

    TEJADA, GRACIELA; GATTI, LUCIANA ; BASSO, LUANA; DOMINGUES, LUCAS G. ; CASSOL, HENRIQUE; CORREIA, CAIO S.C. . CO2 atmospheric measurements and land use and cover change in the Brazilian Amazon. In: ENCONTRO ACADÊMICO DA ENGENHARIA AMBIENTAL DA EEL-USP, 3., 3-4 de junho, 2019, Lorena, SP. Anais... Lorena, SP: Escola de Engenharia de Lorena - USP, 2019.

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  • IPEN-DOC 27461

    RIBEIRO, MAISA M.; GATTI, LUCIANA V. ; BASSO, LUANA S.; FISCH, GILBERTO; NEVES, RAIANE A.L.; CRISPIM, STEPHANE P.. Estudo da altura da camada limite planetária na região sudeste da Floresta Amazônica. In: ENCONTRO ACADÊMICO DA ENGENHARIA AMBIENTAL DA EEL-USP, 3., 3-4 de junho, 2019, Lorena, SP. Anais... Lorena, SP: Escola de Engenharia de Lorena - USP, 2019.

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  • IPEN-DOC 27460

    NEVES, RAIANE A.L.; GATTI, LUCIANA V. ; CRISPIM, STEPHANE P.; RIBEIRO, MAISA M.; MARANI, LUCIANO; CORREIA, CAIO S.C. . Desenvolvimento de metodologia analítica para análise de isótopos de carbono em amostras de ar da Amazônia. In: ENCONTRO ACADÊMICO DA ENGENHARIA AMBIENTAL DA EEL-USP, 3., 3-4 de junho, 2019, Lorena, SP. Anais... Lorena, SP: Escola de Engenharia de Lorena - USP, 2019.

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  • IPEN-DOC 27459

    CRISPIM, STEPHANE P.; GATTI, LUCIANA V. ; BASSO, LUANA S.; SANTOS, RICARDO S. dos ; BORGES, VIVIANE F. ; NEVES, RAIANE A.L.. Estudo da concentração de hexafluoreto de enxofre (SF6) na costa norte e nordeste do Brasil. In: ENCONTRO ACADÊMICO DA ENGENHARIA AMBIENTAL DA EEL-USP, 3., 3-4 de junho, 2019, Lorena, SP. Anais... Lorena, SP: Escola de Engenharia de Lorena - USP, 2019.

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  • IPEN-DOC 27458

    CORREIA, CAIO S.C. ; GATTI, LUCIANA V. ; RIBEIRO, MAISA M. ; NEVES, RAIANE A.L.; CRISPIM, STEPHANE P.; DOMINGUES, LUCAS G. . Medidas de óxido nitroso sobre a Bacia Amazônica com o uso de aviões de pequeno porte: um estudo de longo tempo. In: ENCONTRO ACADÊMICO DA ENGENHARIA AMBIENTAL DA EEL-USP, 3., 3-4 de junho, 2019, Lorena, SP. Anais... Lorena, SP: Escola de Engenharia de Lorena - USP, 2019.

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  • IPEN-DOC 27457

    BASSO, LUANA S.; GATTI, LUCIANA V. ; MARANI, LUCIANO; DOMINGUES, LUCAS G. ; CRISPIM, STEPHANE P.; NEVES, RAIANE A.L.. Determinação das concentrações de CH4 na Amazônia Brasileira utilizando perfis verticais de avião. In: ENCONTRO ACADÊMICO DA ENGENHARIA AMBIENTAL DA EEL-USP, 3., 3-4 de junho, 2019, Lorena, SP. Anais... Lorena, SP: Escola de Engenharia de Lorena - USP, 2019.

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  • IPEN-DOC 27456

    SANTIAGO, A.G.; CAMPOS, C.S.; MACEDO, M.M.G.; DAGUANO, J.K.M.B.; DERNOWSEK, J.A. ; RODAS, A.C.D.. Exploring different Convolutional Neural Networks architectures to identify cells in spheroids. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 2256-2260.

    Abstract: The cultivation of cells in 3D has gained more interest in research once 3D architecture can be closer to full cell physiological functionality. The cultivation of the cells in a spheroid format has shown very promising results, further for bioprinting developing so fast during the last decade. The interaction of spheroids and the matrix, or bioink, have proportionate new structures to be analyzed, specially if one would like to follow the whole system (spheroid and bioink) without fluorescent dyes. Trying to solve this image limitation, the aim of this paper is to present a study on different Convolutional Neural Networks (CNN) architectures employed to identify different structures in fibroblast NIH-3T3 spheroids. Three different architectures were considered: GoogleNet, ResNet18 and AlexNet, all implemented in Python 3.7 using the PyTorch Application Interface Programming (API). Given a spheroid image taken in a light microscope, four structures can be identified: the cell, the dead cell, the impurity/contamination and the background consisting of a gel in which the spheroid is immersed. All four CNN architectures were trained and evaluated with a dataset consisting of over 370 samples, split into a training set (≈ 70%), a test set (≈ 20%) and a validation set (≈ 10%). Since our dataset has unbalanced classes, a data augmentation was applied in order to provide a comparable number of samples for all classes being considered.

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  • IPEN-DOC 27455

    PIERETTI, EURICO F. ; NEVES, MAURICIO D.M. das ; ANTUNES, RENATO A.. Corrosion analysis of a marked biomaterial. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 1968-1973.

    Abstract: Marking is one of the last steps of manufacturing an implantable biomaterial. The marks on its surface constitute a permanent set of information in order to provide identification and traceability of the biomedical device. These markings become stress concentrators and regions with probability for the occurrence of failures that can lead to fracture; besides damaging the passive layer, naturally formed on stainless steels surfaces, favoring the beginning of several forms of degradation. This work presents the effect of two metal implant marking techniques on the corrosion resistance of ISO 5832-1 austenitic stainless steel, one of the most used surgical biomaterials used in Brazil. Engraving was carried out with mechanical and laser beam marking techniques were prepared. The electrochemical behavior was characterized by cyclic potentiodynamic polarization curves and indicate that the laser marking technique is the one that most affects the passive layer of the material when compared to the mechanical engraving.

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  • IPEN-DOC 27454

    NAMBA, A.F.; DEL-VALLE, M. ; DAGHASTANLI, N.A.; ANA, P.A.. In vitro study of the microstructural effects of photodynamic therapy in medical supplies when used for disinfection. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 1705-1710.

    Abstract: Cleaning and disinfecting surfaces and materials in health services are primary elements in infection control measures. For thermosensitive materials, the chemical agents used have disadvantages such as the odor of the products, which can cause allergic reactions to patients and the nursing staff. Photodynamic therapy (PDT) has been shown to be an effective technique in the treatment of infections caused by different microorganisms; however, nothing is known about the effects of this technique on the microstructure of hospital supplies. This in vitro study aimed to evaluate the effects of 0.2% peracetic acid, 1% sodium hypochlorite and PDT with 0.01% methylene blue on the composition and color changes of hospital masks and extensions. For this purpose, 100 mask samples and 100 extension samples were randomly distributed in 20 experimental groups (n = 10, 10 groups for each material), in which the applied substance was varied (sodium hypochlorite, peracetic acid and PDT) and the number of applications (without application, 1, 2 or 3 applications). The compositional analysis was performed by Fourier transform infrared spectroscopy, while the color changes were evaluated using image analysis by CIElab method evaluating the parameters L*, a*, b* and ∆E. The statistical analysis was performed at 5% significance level. It was observed that all agents altered the composition of the materials in a similar way. Although all agents promoted changes in different parameters evaluated, peracetic acid and methylene blue alone altered the final color perceived only in extensions. It was concluded that 0.2% peracetic acid, 1% sodium hypochlorite and PDT alter the chemical composition of both masks and extensions, and that such changes have a positive relationship with the number of treatments performed. These compositional changes may be related to the color changes promoted in both materials by all agents tested.

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  • IPEN-DOC 27453

    FORJAZ, C.R.H.; ZEZELL, D.M. ; ANA, P.A.. Temperature generation and transmission in root dentin during Nd:YAG laser irradiation for preventive purposes. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 1031-1035.

    Abstract: High-intensity lasers are widely used in dental procedures and the heating produced on the surface is necessary to ensure protective activity against the development of caries and erosion lesions. However, caution should be exercised regarding the spread of heat to the pulp, periodontal tissue and alveolar bone, which can cause harm to these tissues. This study sought to evaluate the generation and transmission of heat in the root dentin and adjacent tissues during irradiation with Nd:YAG laser for preventive activity. For that, 15 lower incisor human teeth had an area of 9 mm2 of root dentin irradiated with Nd:YAG laser (λ=1.064 μm, 10 Hz, 60 mJ/pulse, 84.9 J/cm2) for 30s. During irradiations, pulpal temperature was evaluated by fast-response thermocouples, while surface temperature and heat distribution on surrounding tissues were measured by infrared thermography. It was observed a mean surface temperature increase of 293.48±30.6° C in root dentin surface, and 15.85 ± 39.6° C below the irradiated area, 11.72 ± 8.7° C above the irradiated area, 19.77 ± 4.9° C at 1 cm laterally and 7.03 ± 2.7° C at 2 cm laterally to the irradiated area. The mean pulpal temperature augment registered was 6.5±1.4° C. It can be concluded that Nd:YAG laser irradiation promoted surface temperature rises that suggest chemical changes on dentin; however, the temperature increases generated in the adjacent tissues (region of periodontal ligament) and in the pulp chamber may be dangerous in future clinical application considering the irradiation time of 30 s made in this study. Therefore, this laser protocol can be used as long as the irradiation time is reduced in future studies.

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  • IPEN-DOC 27452

    CARVALHO, C.M.S.; MARINELI, A.G.F.; SANTOS, L. dos; FREITAS, A.Z. de ; AMARAL, M.M.. Evaluation of the Heart Rate Variability with Laser Speckle Imaging. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 430-433.

    Abstract: The Autonomic Nervous System (ANS) is responsible for regulating various physiological processes in the human body. The Heart Rate Variability (HRV) represents a measurement used in evaluating the modulation of the ANS in different physiological conditions such as stress, physical activity, sleep, metabolic alterations, and, also, pathological conditions. Physical activity results in important changes in the cardiovascular system, such as an increase in blood flow and a decrease of the peripheral vascular resistance. Monitoring the peripheral microcirculation represents an important aid in evaluating the general conditions of an individual. The Laser Speckle Contrast Analysis (LASCA) is a non-invasive optical resource developed that uses nonionizing radiation in the region of the infrared and is important in the diagnosis of problems regarding the peripheral microcirculation. This work aimed to implement a method to obtain the HRV through the peripheral microcirculation utilizing the Laser Speckle Contrast Analysis (LASCA) technique. A commercial LASCA equipment was used to obtain a face-video. A custom software was implemented to process the LASCA videos and obtain the HRV. A heart rate monitor (HRM) was also utilized to measure the HRV and the values were compared against the ones obtained with LASCA. The method had consistent results in obtaining both the pulsation and the HRV, making it possible for future studies to use such a technique.

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  • IPEN-DOC 27348

    LEMOS, F.L. ; BIANCHI, P.H. . A systemic approach to information and cyber security. In: INTERNATIONAL CONFERENCE ON NUCLEAR SECURITY, February 10-14, 2020, Vienna, Austria. Proceedings... 2020. p. 1-6.

    Abstract: Design Based Threat, or DBT, is a common principle for physical and cyber protection, which is based on threat assessments. The protection, cyber or physical, will be planned based on the type of the identified threat. While we acknowledge the importance of the DBT, we argue that following this line of reasoning may limit our ability to grasp other vulnerabilities the system may have due to the following assumptions: a) The system will behave according to the way we think it should, based on a predetermined fashion. b) If each component of the system is reliable, then the system will be reliable. Systems theory assumes that accidents are a result of systemic factors, and does not have a single root-cause, generally a failure, that starts a chain of events leading to the accident. Moreover, systems theory assumes that security and safety are emergent properties of a system that result from the interactions between the components of that system. Therefore, accidents are a problem of control of the interactions between the components of the system rather than a problem of failures of components. In the systemic approach a cyber security system is treated as part of the whole socio-technical complex system, where humans are components of the system and interact with the computerized controls. The organizational culture permeates the entire system affecting decisions and, consequently, the interactions between the components. Weak safety and security cultures will eventually contribute for the system to migrate to hazardous states leading to losses or accidents. The paper analyzes the roles of organizational, safety and security cultures, as underlying factors that can lead to the deterioration of the hierarchical control structure, which is supposed to keep the interactions between the components of the system within desirable constraints.

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  • IPEN-DOC 27339

    TESSARO, ANA P.G. ; ROLINDO, NATALIE C. ; MARUMO, JULIO T. ; VICENTE, ROBERTO ; LAS CASAS, ALEXANDRE . Use of ionizing radiation for treatment and extraction of organic compounds from petroleum sludge. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 45th, March 3-7, 2019, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2019. p. 1-7.

    Abstract: This paper presents preliminary results of a technical feasibility study of the use of an electron beam accelerator for the treatment of petroleum sludge and the degradation of organic and inorganic compounds. After analyzing the results of previous studies, the doses of the pilot study were defined.

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  • IPEN-DOC 27338

    ROLINDO, NATALIE C. ; TESSARO, ANA P.G. ; SMITH, RICARDO B. ; CAMPOS, CESAR ; SAID, YASSER ; MARUMO, JULIO T. ; VICENTE, ROBERTO . Inventory and characterization of categories 3-5 disused sealed radioactive sources. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 45th, March 3-7, 2019, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2019. p. 1-10.

    Abstract: Brazil has one of the biggest inventories of SRS in the world, not only because of the large industrial park, the well-developed health care infrastructure and the numerous mining operations, but also by the use of radioactive sources in consumer products, such as smoke detectors, lightning arresters, surge protectors and even cardiac pacemakers. Presently, the inventory of DSRS at the WML is of more than 10,000; if the sources from lightning arresters, smoke detectors and Ir-192 with activities above the clearance levels are included, the estimate is over 150,000. The Waste Management Laboratory (WML) of the Nuclear and Energy Research Institute (IPEN/CNEN-SP) is responsible for the management and treatment of these sources. An important aspect to consider is that Brazil does not have a defined strategy or a protocol for screening and inventorying these sources, whose management was limited only to storage. The WML started the development of methods and operational work, to characterize and reduce the total volume of this inventory for the borehole-type final disposal facility yet to be constructed, where the DSRS will be disposed of. The information available from these sources is in a database created in 1980, when the sources began to be received. Several records on the FRSD that were checked are incomplete or simply incorrect, since there is no correspondence between the dates of entry of these sources in the storage and their physical characteristics. Some reasons can be listed to try to understand the divergences: the inspection when receiving the sources was not possible, no inspection procedure was defined, there were technical difficulties to open the packages. The objective of this work is to organize the inventory in a standardized way, control access, traceability, reduction of the necessary time to locate and characterize the sources upon reception, and of the repetitive work in the operational routine, and finally release of space in the storage.

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  • IPEN-DOC 27337

    SMITH, RICARDO B. ; TESSARO, ANA P.G. ; ROLINDO, NATALIE C. ; VICENTE, ROBERTO . Further analyses of the unburied Goiania Accident packages. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 45th, March 3-7, 2019, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2019. p. 1-7.

    Abstract: In 1987, in the city of Goiania, Brazil, a derelict teletherapy machine was disassembled by scavengers and Cs-137 was released in the environment, unleashing the biggest radiological accident in Brazil. During the 15 days before the accident was acknowledged, some contaminated materials were sold and delivered to recycling factories in a few cities in the state of Sao Paulo, Brazil, in the form of metal scrap and recycled paper bales. The contaminated material was then collected, the metal scrap was conditioned in forty-three 200-liter drums, and the paper bales were stored in fifty 1.6 cubic meter steel boxes at the interim storage of the Nuclear and Energy Research Institute (IPEN), in the city of Sao Paulo, and there remained ever since. In 2017, 30 years later, initial analyses were performed at a sample of these boxes, checking for their activity, weight, and incongruences between the original values recorded at the time of collection and the measurement results 30 years later. The results indicated that none of the boxes checked were close to the clearance limit and that, without any sort of treatment, this radioactive waste should be stored for at least 150 years more. Visual inspection could not be performed at that time. Nowadays, some of the boxes were opened and samples from the contaminated material inside were taken for analysis. The main objective of this work is to report the results from the evaluation of the physical state of this material. After these analyses, the treatment options for volume reduction that were previously proposed were reviewed, and the method that best suits the current characteristics of the waste was chosen.

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  • IPEN-DOC 27336

    SILVA, SIDNEY L. da; PRADO, FELIPE M.; TOFFOLI, DANIEL J.; WETTER, NIKLAUS U. . Measuring photoelastic dispersion coefficients in material samples with digital holography. In: BJELKHAGEN, HANS I. (Ed.) SPIE PHOTONICS WEST; SPIE OPTO, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 113060P-1 - 113060P-7. (Proceedings SPIE 11306, Practical Holography XXXIV: Displays, Materials, and Applications). DOI: 10.1117/12.2544874

    Abstract: Polarized Digital Holography (PHD) is a fast and efficient tool for analyzing mechanical effects in materials. Especially when the task requires non-invasive techniques that do not damage the material in study, the use of PHD has great perspectives. The most common methods of digital reconstruction use the convolution theory to discretize the Huygens- Fresnel integral. When external stresses are applied to photoelastic materials, the relationship between these stresses and phase differences observed by polarization holography is an intrinsic characteristic of the material called the photoelastic dispersion coefficient. In photoelasticity, this coefficient depends on the wavelength. By using PHD the authors show in the present paper that the photoelastic dispersion coefficient also depends on the wavelength in Holography. A Mach- Zehnder interferometer, modified with the inclusion of linear polarizers, was built to verify this effect in a sample of photoelastic material. In this set-up, two coherent light sources with different wavelengths were used. For the analysis, a digital method was created that correlated the mean stresses differences on the photoelastic material sample and the mean phases differences at each distinct wavelength.

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  • IPEN-DOC 27335

    FREITAS, ANDERSON Z. de ; RIBEIRO, LUCAS A. de S. ; NEGRINI NETO, OSVALDO ; SARKIS, JORGE E.S. ; SIQUEIRA, ANDRESSA N. . Optical-coherence-tomography-based algorithm for handwriting forensic analysis. In: JALALI, BAHRAM (Ed.); KITAYAMA, KEN-ICHI (Ed.) SPIE PHOTONICS WEST; SPIE OPTO, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 112990P-1 - 112990P-8. (Proceedings SPIE 11299, AI and Optical Data Sciences). DOI: 10.1117/12.2543356

    Abstract: This work describes a new method for handwriting forensic analysis using optical coherence tomography (OCT) images. The region of interest (ROI) in documents signature to be analyzed were pre-selected with a traditional optical analyzer (Docucenter 2000 – Projectina®) equipped with different wavelengths light sources and bandpass filters coupled detector. The ROI where then submitted to OCT to 3D imaging (OCP930SR, Thorlabs Inc.) with optical resolution of 6.0 microns. One original and 5 falsified signatures were produced by 5 different individuals, using a block of 5 sheets of white sulfite paper A4 size and weight of 75 g/m^2, using the same blue ballpoint pen and in the same surface. For pressure pen calibration, were developed a system computer controlled to maintain the pressure constant during writing linear traces, 15 different pressure configuration were applied to each linear trace, resulting in a relation between deformation and applied pressure. An autonomous algorithm was developed to make surface detection, across OCT tomographic images, correct the paper surface curvature, detect and measure deformation on paper due to pen pressure, generating a new image in false color from differential pressure, based in previous calibration. This new image can be considered as a “fingerprint pressure” signature. This methodology may assist the forensic expert in correctly determining the authorship of a signature.

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  • IPEN-DOC 27334

    DIPOLD, JESSICA ; SILVA, DANILO A.A. da ; BERECZKI, ALLAN ; JIMENEZ-VILLAR, E. ; WETTER, NIKLAUS U. . Polydispersed Nd3+:YVO4+SiO2 powders for highly efficient random lasers. In: JIANG, SHIBIN (Ed.); DIGONNET, MICHEL J.F. (Ed.) SPIE PHOTONICS WEST; SPIE OPTO, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 112760N-1 - 112760N-8. (Proceedings SPIE 11276, Optical Components andMaterials XVII). DOI: 10.1117/12.2545028

    Abstract: Random lasers are cheap and easy to fabricate, having several different applications such as early cancer detection, encryption and Speckle-free imaging. However, few fabricated random lasers present high efficiency, which limits their possible applications. In a recent work, our group achieved a record efficiency by developing random lasers that use compacted, polydispersed yttrium vanadate doped with neodymium (Nd3+:YVO4 ) powders to create separate regions for gain and light diffusion. Large particles are responsible for the light diffusion, while the small particles that occupy the spaces between them create gain pockets, absorbing the pumped light. In this work, this strategy is refined by using passive particles (SiO2) for light diffusion, restricting the laser active particles to the gain pockets. The first attempt with this strategy used 30% of Nd3+:YVO4 small powders and 70% of large SiO2 particles. Without any further optimization, the result achieved is already 40% of the highest obtained efficiency in the previously studied Nd3+:YVO4 polydisperse sample, showing a promising result to further improve this new strategy and reach even larger efficiencies with less laser active material.

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  • IPEN-DOC 27333

    WETTER, NIKLAUS U. ; SILVA, DIEGO S. da ; KASSAB, LUCIANA R.P.; ROSSI, WAGNER de . Double line Neodymium doped GeO2-PbO waveguide amplifier for the second telecom window. In: JIANG, SHIBIN (Ed.); DIGONNET, MICHEL J.F. (Ed.) SPIE PHOTONICS WEST; SPIE OPTO, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 112760M-1 - 112760M-7. (Proceedings SPIE 11276, Optical Components and Materials XVII). DOI: 10.1117/12.2544291

    Abstract: We report the production of active double waveguides in germanate glasses, GeO2-PbO doped with Nd3+, by direct femtosecond laser writing. The glasses were produced using the melt-quenching technique and the active waveguides were written using 30 fs laser pulses at 800 nm with different parameters of writing speeds and pulse energies depending on the rare earth elements used for doping. The photo-induced refractive index change was 5.2x10-3. The Nd doped sample exhibited a relative gain of 3.6 dB/cm for 1.6 mW of 805 nm pump power. The results obtained in present work demonstrate that Nd3+ doped GeO2-PbO glasses are promising materials for the fabrication of integrated amplifiers, lossless components and lasers based on germanate glasses.

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  • IPEN-DOC 27332

    BERECZKI, A. ; PAES, JOAO P.F. ; WETTER, NIKLAUS U. . Three-level Nd:YLF Raman laser directly pumped by a beam shaped diode bar. In: KUDRYASHOV, ALEXIS V. (Ed.); PAXTON, ALAN H. (Ed.); ILCHENKO, VLADIMIR S. (Ed.); ARMANI, ANDREA M. (Ed.) SPIE PHOTONICS WEST; SPIE LASE, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 1126614-1 - 1126614-8. (Proceedings SPIE 11266, Laser Resonators, Microresonators, and Beam Control XXII). DOI: 10.1117/12.2544844

    Abstract: Low heat generation can be obtained when pumping Nd:YLF at wavelengths of 872 nm and 880 nm and emitting at the three-level transition of 908 nm. These transitions show very low quantum defect with efficiencies of 0.96 and 0.97, respectively. However, the low average absorption cross-section at these wavelengths makes efficient absorption even for longitudinal pump setups difficult. Using a beam-shaped pump diode instead of a fiber-coupled diode bar may be an effective means of increasing absorption because it can provide for π-polarized radiation which shows higher absorption cross section. In this work, a Nd:YLF was pumped at 872 nm by a diode bar using beam-shaping. Results were compared to pumping at 872 and 880 nm with non-polarized fiber-coupled diodes. Stimulated Raman scattering was also obtained with a KGW crystal generating first Stokes emissions at 990 nm and 976 nm.

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  • IPEN-DOC 27331

    BERECZKI, A. ; WETTER, NIKLAUS U. . Dynamically stable lasers from commercial Nd:YAG modules with high beam quality and single-frequency: the correct choice of the fundamental waist size at the rod. In: KUDRYASHOV, ALEXIS V. (Ed.); PAXTON, ALAN H. (Ed.); ILCHENKO, VLADIMIR S. (Ed.); ARMANI, ANDREA M. (Ed.) SPIE PHOTONICS WEST; SPIE LASE, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 1126617-1 - 1126617-10. (Proceedings SPIE 11266, Laser Resonators, Microresonators, and Beam Control XXII). DOI: 10.1117/12.2545005

    Abstract: Diode-side pump Nd:YAG rod modules are widely available, reliable and commercially very attractive for building continuous-wave solid-state lasers in the 10-1000 W range. Newer technologies such as fiber or thin disk lasers are generally much more expensive but have the benefit of better beam quality and higher output powers if necessary. By using well-known techniques for designing dynamically stable resonators (DSRs), lasers with high extraction efficiency and high beam quality (fundamental mode, TEM00) can be obtained also with diode side-pumped modules. However, a successful project for a dynamic stable laser depends critically on the correct choice of the fundamental mode diameter within the rod. DSR design rules are based on the beam waist, w3, at the rod principal planes by considering the rod as a thin thermal lens, which differs significantly from real resonators. Here we give guidelines and criteria on how to establish the correct diameter in each case. Using off-the-shelf 75 W Nd:YAG modules it was possible to obtain linearly polarized TEM00-mode output of 30 W with M2=1.08 from a single module, M2=1.2 and 76.5 W of output power using two modules and 100.5 W of polarized, continuous output with M2=1.8. A single-frequency ring laser was also built, using two modules, generating 51.6 W of fundamental wave single-frequency output.

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  • IPEN-DOC 27330

    FERREIRA, MERILYN S. ; PASK, HELEN M.; WETTER, NIKLAUS U. . Nd:YLF/KGW intracavity Raman laser in DBMC configuration at 1147 and 1163 nm in TEM00. In: CLARKSON, W. ANDREW (Ed.); SHORI, RAMESH K. (Ed.) SPIE PHOTONICS WEST; SPIE LASE, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 112590K-1 - 112590K-7. (Proceedings SPIE 11259, Solid State Lasers XXIX: Technology and Devices). DOI: 10.1117/12.2545092

    Abstract: A Nd:YLF / KGW intracavity Raman laser in DBMC (double-beam-mode-controlling) configuration has been investigated in this work. The fundamental wavelength laser was generated using a Nd:YLF crystal pumped in DBMC configuration generating an emission wavelength of 1053 nm in σ-polarization. A VBG (volume-Bragg-grating) equipped diode emitting at 797 nm was used as pump source. The KGW crystal has two strong Raman lines, 768 cm-1 and 901 cm-1, generating two Raman wavelengths at 1147 nm and 1163 nm, respectively. The DBMC technique allows to produce TEM00 stable output in a side-pumped configuration with no requirement to introduce any additional mode selection technique, thus achieving high efficiency for fundamental TEM00 operation. The high power density of the fundamental laser combined with intracavity Stokes conversion produces an efficient Raman laser. Allying both techniques, the Nd:YLF in DBMC configuration and the intracavity Raman generation, it was possible to generate an output power at 1163 nm of 3.2 W corresponding to a diode-to-Raman conversion efficiency of 8% with slope efficiency of 8.8 %. For the emission at 1147 nm, 3.5 W of output power was achieved with a diode-to-Raman conversion efficiency of 11% and slope efficiency of 9%. The beam quality was M2 =1.9 and 1.1 in the horizontal and vertical direction, respectively. This is, to our knowledge, the first report of a side-pumped Nd:YLF/KGW intracavity Raman laser in DBMC configuration.

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  • IPEN-DOC 27321

    MAZIERO, J.S. ; ROGERO, S.O. ; DAMASCENO, K.C. ; ORMENIO, M.B. ; CAVALCANTE, A.K. ; MARTINI, G.A. ; BATISTA, J.G.S. ; KATTI, K.V.; LUGAO, A.B. ; ROGERO, J.R. . Avaliação da toxicidade de nanopartículas de prata estabilizadas com goma arábica. In: WORKSHOP DE BIOMATERIAIS, ENGENHARIA DE TECIDOS E ORGÃOS ARTIFICIAIS, 6th, October 29-31, 2019, São Paulo, SP. Proceedings... 2019. p. 403-413.

    Abstract: As nanopartículas de prata (NPAg), devido a seus diversos atributos (formato variado, elevada área superficial e alto poder bactericida), vem sendo amplamente utilizadas em diversos setores da indústria. Esta utilização abrangente, tem provocado grande preocupação, quanto aos impactos e riscos potenciais que as NPAg podem causar ao meio ambiente e à saúde humana. Este trabalho teve como objetivo verificar a toxicidade de uma amostra de NPAg estabilizada com Goma Arábica e reduzida com Tri-Alanina, utilizando ensaios in vitro e in vivo. O teste in vitro de citotoxicidade, foi realizado seguindo a norma ISO 10993 - 5, em células da linhagem NCTC-L929; os ensaios in vivo de ecotoxicidade aguda, de acordo com a norma brasileira ABNT NBR 12713, utilizando como organismo teste a Daphnia similis; e embriotoxicidade aguda de acordo com o protocolo da OECD 236, utilizando como organismo teste o Danio rerio. Os resultados obtidos foram: IC50 de 2,61 mg L-1, CE50 de 6,55 μg L-1 e CL50 de 673 μg L-1. Os organismos aquáticos apresentaram maior sensibilidade às NPAg do que as células em cultura, elevando a importância de se realizar mais estudos em várias espécies de interesse biológico. Além disso, mostra-se necessário verificar o descarte apropriado dessas nanopartículas, visto que no Brasil ainda não há legislações que quantifiquem os limites permissíveis para esse descarte.

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  • IPEN-DOC 27107

    PEREIRA, VIVIAM S.M.; ANTUNES, RENATO A.; OLIVEIRA, MARA C.L. de; CORREA, OLANDIR V. . Efeito de tratamentos de envelhecimento sobre a resistência à corrosão da liga de magnésio AZ91D / Ageing heat treatments effect on the corrosion resistance of the AZ91D magnesium alloy. In: CONGRESSO INTERNACIONAL ANUAL DA ABM, 67th, July 31 - August 7, 2012, Rio de Janeiro, RJ. Proceedings... 2012. p. 192-202.

    Abstract: O efeito de tratamentos térmicos de envelhecimento (T6) sobre a resistência à corrosão da liga de magnésio AZ91D foi estudado. Amostras solubilizadas a 445°C por 24 h foram envelhecidas a 200 °C por tempos de 8 h, 16 h e 24 h. Todos os tratamentos foram realizados em forno mufla, sob atmosfera inerte (argônio), seguidos de resfriamento em água. Para observação das alterações microestruturais, utilizaram-se as técnicas de microscopia óptica e de MEV. O comportamento eletroquímico foi avaliado por ensaios de espectroscopia de impedância eletroquímica e de polarização potenciodinâmica, utilizando-se solução de Hanks, a 37 °C como eletrólito. O período de imersão foi de 7 dias. Com o tratamento de solubilização, ocorreu a dissolução do constituinte eutético, restando somente a matriz (fase α-Mg) saturada com alumínio, juntamente de resquícios de β- Mg17Al12. Com o tratamento de envelhecimento foram observados precipitados ricos em alumínio (β-Mg17Al12) sobre a matriz. A amostra envelhecida por 8 h foi a que mostrou menor valor de resistência à corrosão; as amostras tratadas por 16 h e 24 h apresentaram valores de impedância semelhantes, sendo que a amostra envelhecida por 16 h apresentou o melhor desempenho.

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  • IPEN-DOC 27083

    MARTINS, E.W. ; CARDOSO, J.V.; POTIENS, M.P.A. . Determination of computed tomography quantities using a new pediatric phantom. In: INTERNATIONAL CONFERENCE ON RADIATION PROTECTION IN MEDICINE: ACHIEVING CHANGE IN PRACTICE, December 11-15, 2017, Vienna, Austria. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2018. p. 1-5.

    Abstract: A computed tomography pediatric head phantom that uses special materials to simulate the cortical and the cancellous bone was developed. This paper shows its behavior to determine the specific computed tomography radiation quantities at two calibration laboratory, the LCI-IPEN, Brazil and LMRI-IST, Portugal. The specific quantities measured were: air kerma index(Ca,100), weighted air kerma index (Cw), average volumetric air kerma index (Cvol) and the air kerma- lenght product (PKL). The reference radiation qualities used in both laboratories were the radiation qualities recommended by the norm IEC 61267 (RQT8, RQT9 e RQT10) to computed tomography dosimetry measurements. The calculated values of CW show attenuation of 11%, 13% and 10% for the qualities RQT 8, RQT 9 and RQT 10, respectively, from cortical to cancellous bone.

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  • IPEN-DOC 27080

    GERALDO, BIANCA ; VICENTE, ROBERTO ; FERREIRA, ROBSON J. ; MADUAR, MARCELO F. ; GOES, MARCOS M. ; MARUMO, JULIO T. . Radiochemical method for characterization of the filter cartridges from the IEA-R1 reactor. In: ANNUAL WASTE MANAGEMENT CONFERENCE, March 6-10, 2016, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2016. p. 1-5.

    Abstract: The filter cartridges used in water purification system of the IEA-R1 research reactor become radioactive waste after the end of their useful life. The characterization of this waste is one step in their management, which aims at identifying and quantifying the radionuclides present, including those known as "difficult to measure" (DTM) radionuclides. Wastes from nuclear reactors contain fission and activation products and transuranic elements, only few of them emitting gamma radiation measurable by simple gamma spectrometry methods. In routine waste management activities, the concentrations of the DTM can only be estimated by indirect methods such as scaling factors. The method of the scaling factors uses empirically determined proportions between the concentrations of DTM radionuclides and that of easily measurable gamma emitters called key nuclides (KN), to calculate DTM concentrations. Determining the scaling factors for the filter cartridges is a hard task when the number of samples is large, not only because the preparation of samples is difficult but also because the number of radionuclides to analyze is large. If it can be demonstrated that DTM and KN are both distributed evenly in the filters, less samples from each filter are necessary, reducing lab work. The aim of this paper is to present the results of the assessment of homogeneity along the filter cartridges by gamma spectrometry of chemically reduced samples. Five thin slices of five filters were burnt and the ashes quantitatively dissolved and the activity concentration of the solutions determined by gamma spectrometry.

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  • IPEN-DOC 27079

    FERREIRA, EDUARDO ; VICENTE, ROBERTO ; TURRILLAS, XABIER; YOKAICHIYA, FABIANO; FRANCO, MARGARETH ; MARTINEZ, LUIS G. ; CARVALHO, ALEXANDRE; MARUMO, JULIO T. . Effects of gamma radiation on cementitious materials in repository environment. In: ANNUAL WASTE MANAGEMENT CONFERENCE, March 6-10, 2016, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2016. p. 1-10.

    Abstract: Cementitious materials are widely used in the management of radioactive waste and have to perform as required for the period of service life of the installation. In order to assess the long term durability of cement paste in a deep borehole for radioactive wastes, specimens were casted in laboratory and exposed to a gamma radiation field. The effects of the radiation in the specimens were evaluated by X-Ray Diffraction, as changes observed in the mineralogy and microstructure of the material after irradiation doses varying between 0 (without radiation) and 10 MGy. It was observed that the specimens exposed to higher doses of gamma radiation (up to 3MGy) presented differences between surface and core, when compared with the samples with no radiation or exposed to low doses. These results are important to model the behavior of cementitious materials under the conditions expected in a borehole repository and to provide data for the safety assessment of the installation.

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  • IPEN-DOC 27071

    FERREIRA, E.S.; BENETTI, C.; ZEZELL, D.M. ; KATO, I.T.; ANA, P.A.. Efeitos da irradiação com laser de Er,Cr:YSGG na temperatura pulpar e superficial da dentina radicular. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 1937-1940.

    Abstract: Tendo em vista o envelhecimento da população e a permanência dos dentes na cavidade oral, observou-se um aumento da incidência da cárie radicular em idosos. Os lasers de érbio podem ser usados para prevenção de cárie; contudo, ainda não são estabelecidos parâmetros de irradiação que sejam seguros para os tecidos pulpares e periodontais e que sejam efetivos para ocasionar alterações químicas na superfície da dentina. Este estudo avaliou os efeitos da irradiação da dentina radicular com laserde Er,Cr:YSGG na temperatura pulpar e superficial da dentina, buscando-se determinar parâmetros de irradiação seguros e efetivos para futura aplicação clínica. Para tal, foi realizado um estudo in vitro randomizado com duas fases experimentais. Na primeira fase, 30 blocos de dentina radicular bovina foram empregados para avaliar a temperatura superficial ocasionada por um único pulso laser empregando-se termografia no infravermelho, enquanto que, na segunda fase experimental, 30 dentes incisivos inferiores humanos foram empregados para avaliação da temperatura pulpar durante as irradiações por 10 segundos empregando-se termopares de resposta rápida. As irradiações foram efetuadas com laser de Er,Cr:YSGG,  = 2,78 μm, 20 Hz, sem refrigeração, com potências médias de 0,1 W, 0,25 W e 0,5 W, o que resultou em densidades de energia de 2,4 J/cm2, 6 J/cm2 e 12 J/cm2, respectivamente. Observou-se variações de temperatura superficial de 61  26 oC, 75  34 oC e 172  36 oC para os grupos irradiados com potência média de 0,1 W, 0,25 W e 0,5 W, respectivamente. Foram registradas elevações médias de temperatura pulpar de 0,81 ± 0,4 oC, 1,76 ± 0,7 oC e 2,95 ± 1,33 oC, para os grupos irradiados com potência média de 0,1 W, 0,25 W e 0,50 W, respectivamente. Concluiu-se que o laser de Er,Cr:YSGG promove elevações de temperatura superficiais que indicam a ocorrência de transformações químicas na superfície da dentina radicular; contudo, dos parâmetros testados, se considerarmos as elevações de temperatura pulpar, a potência média de 0,25 W é a que se apresenta mais promissora para futuro uso para prevenção da cárie radicular.

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  • IPEN-DOC 27070

    GONÇALVES, KARINA de O.; SILVA, MONICA N. da; COURROL, LILIA C. . Síntese de nanopartículas de ouro funcionalizadas com ácido aminolevulínico e laser de pulsos ultracurtos. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 1913-1916.

    Abstract: As nanopartículas de ouro apresentam inúmeras aplicações na medicina. As diferenças de tamanho, forma e propriedades de superfície, fazem com que suas aplicações se tornem versáteis, como por exemplo, a terapia fototérmica e o rastreamento de tumores (biomarcadores). Foi recentemente demonstrado na literatura que a incorporação de nanopartículas de ouro na estrutura do ácido 5-aminolevulínco (5-ALA) melhora as propriedades fotodinâmicas do fármaco. O estudo com laser ocorreu visando à possibilidade de modificação no formato das nanopartículas, de esféricas para outras formas, entre elas bastões e prismas que resultam em bandas de plasmons de comprimentos de onda maiores, uma vez que nanopartículas com formato mais cilíndrico apresentam uma janela na região da janela óptica do tecido biológico e desta forma a luz aplicada em PDT teria maior profundidade de penetração no tecido. Assim propomos neste estudo, sintetizar nanopartículas de ouro com 5-ALA, para realizar o diagnóstico e a terapia (Teranóstica) de doenças com crescimento não controlável, de uma forma mais simples, menos invasiva e mais barata.

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  • IPEN-DOC 27069

    PROVASI, C.; CASSIMIRO-SILVA, P.F.; ANA, P.A. da; ZEZELL, D.M. ; GOMES, A.S.L.; LINS, E.C.. Estudo da espectroscopia de reflexão com radiações visíveis e infravermelhas para discriminação de tecidos pulpares humanos sadios e patológicos. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 1909-1912.

    Abstract: A polpa dental é o tecido mais interno do dente. Sua principal função é garantir a dentinogênese e a sensibilidade dental, e por essa razão a informação clínica sobre a saúde da polpa é relevante. Polpas diagnosticadas como não-vitais são encaminhadas para um tratamento endodôntico agressivo, baseado na remoção de todo tecido degradado. Por esse motivo, deve-se haver um esforço em minimizar o número de falsos diagnósticos clínicos da vitalidade pulpar, na intenção de preservar a integridade do paciente. Esse estudo propõe a espectroscopia no visível e no infravermelho como método de melhorar a precisão no diagnóstico do status pulpar. Ele é baseado em confrontar a reflexão óptica dos tecidos no espectro do visível (VIS) e do infravermelho próximo (NIR) (350nm a 1.700nm) no intuito de discriminar polpas humanas vitais de outras polpas sintomáticas de pulpite. A Análise dos Componentes Principais (PCA) sobre os espectros de reflexão ainda propôs modelos matemáticos de diferenciação dos grupos. Os resultados revelaram que a reflexão óptica pode discriminar o status da vitalidade de polpas humanas vivas; e a análise estatística da PCA revelou precisão de acerto de 100% para radiações NIR e 95% para radiações VIS.

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  • IPEN-DOC 27068

    PEREIRA, D.L. ; FREITAS, A.Z. ; ZEZELL, D.M. ; ANA, P.A.. Uso da tomografia por coerência óptica no monitoramento de lesões de erosão e abrasão em dentina. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 1861-1864.

    Abstract: O objetivo deste trabalho foi avaliar o potencial da tomografia por coerência óptica (OCT) para o diagnóstico precoce e monitoramento de lesões de erosão e abrasão em dentina. Para isso, foi realizado um estudo in vitro com 192 blocos de dentina radicular bovina de 8 mm2, distribuídos aleatoriamente em quatro grupos experimentais (n = 48): G1- sem tratamento; G2- tratamento com flúor fosfato acidulado (FFA, 1,23% F-, pH = 3,3–3,9); G3- irradiação com laser de Nd:YAG (1064nm, 0,6W, 10Hz, 84,9J/cm2); G4- aplicação de FFA, seguida de irradiação com laser de Nd:YAG. Após os tratamentos, as amostras foram submetidas a um desafio de erosão e abrasão por escovação (Sprite Zero, pH=2,6, 90s, 4x/dia) e remineralização (saliva artificial, pH=7) durante 15 dias, sendo avaliadas por OCT em 5 momentos distintos: antes e após os tratamentos, e após 5, 10 e 15 dias de desafio. Foi possível observar o desenvolvimento e evolução das lesões de erosão/abrasão e também foi possível relacionar a desmineralização do tecido decorrente do processo de erosão/abrasão com o coeficiente de atenuação óptica.

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  • IPEN-DOC 27067

    OLIVEIRA, L.Z.; WATANABE, T.E.; GOUVEIA, D.S. ; BRESSIANI, A.H.A. ; RIBEIRO, C.. Estudo da síntese para obtenção de hidroxiapatita em meio de colágeno. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 251-254.

    Abstract: A obtenção da hidroxiapatita - HA nanoestruturada pode exigir modificações nas técnicas convencionais de síntese a fim de mimetizar estruturalmente as bioapatitas. A técnica de neutralização já vem sendo explorada em função de sua simplicidade e versatilidade, mas sua reprodutibilidade nem sempre é garantida, sugerindo a formação de fases intermediárias precursoras da HA, e algumas vezes outras fases, como o óxido de cálcio, além do alto estado de aglomeração de suas partículas. Com intuito de obter pós nanométricos de natureza dispersa e garantir a estabilidade da HA foi adicionado colágeno hidrolisado (4% em massa) ao meio de precipitação, variável ainda pouco explorada em processos de síntese. Os pós obtidos foram caracterizados por DRX, sendo observada a presença da fase pura e aumento da cristalinidade após calcinação a 800oC/3h, ainda verificou-se maior perda de massa para esta HA quando comparada a técnica clássica de precipitação (sem colágeno). Os resultados obtidos indicaram a viabilidade da metodologia para obtenção da HA, confirmando a natureza nanométrica dos pós e estabilidade da fase, logo após a síntese, e também após calcinação. A HA sintetizada apresentou cerca de 95% de densificação, microestrutura que pôde ser comprovada por MEV, além de manter sua estrutura cristalina, sem a formação de fase secundária, conforme observado por DRX, após sinterização a 1100oC/1h. A metodologia de síntese, em meio de colágeno, proporcionou a obtenção de pós de HA nanométrica de adequada sinterabilidade e estabilidade, podendo gerar microestruturas densas, mantendo fase única.

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  • IPEN-DOC 27061

    TERADA, M.; QUEIROZ, F.M.; COSTENARO, H.; OLIVIER, M.G.; COSTA, I. ; MELO, H.G. de. Effect of cerium (III) on the corrosion protection properties of the film formed on the AA2524-T3 alloy by hydrothermal treatments. In: EUROPEAN CORROSION CONGRESS, September 11-15, 2016, Montpellier, France. Proceedings... Frankfurt, Germany: European Federation of Corrosion, 2016. p. 1-9.

    Abstract: Many industries use chromium-based anodizing processes with a subsequent sealing post-treatment containing hexavalent chromium ions to protect Al alloys. However, this method of protection causes large environmental and health related problems. This has encouraged the search for new surface treatments for metals with the requirements of effective protection against corrosion and generation of non-toxic residues to the environment. Recent studies are pointing towards chromium free anodizing processes, specifically the tartaric-sulfuric acid (TSA) one, as a viable alternative. Besides, sealing treatments of the Al anodic layer in chromate solutions are another source of toxic residues and their replacement for environmentally friendly alternatives are also of great interest. Surface treatments with cerium ions are being largely studied for the corrosion protection of Al alloys due to their good anticorrosion properties associated to the lack of toxic residues generated. In this investigation, a hydrothermal treatment in aqueous solution with cerium ions has been proposed as a post-treatment for TSA anodizing, and its effects on the AA2524-T3 alloy corrosion resistance investigated. This alloy presents a chemical composition similar to the AA2024 but with lower and more controlled amounts of alloying elements. The sealing treatment was carried out by immersion in aqueous solutions with cerium ions at the boiling temperature. The effect of Ce on the characteristics of the surface film formed, such as morphology and corrosion resistance, was investigated by SEM and electrochemical impedance spectroscopy. The results were compared to those of sealing in boiling water. The results showed that the sealing treatment in solution with Ce(III) ions presented a less stable behavior than the sealing with only boiling water. However, the results of the EIS experiments showed recovery of the protective properties of the system, indicating that some self-healing properties must be imparted to the system.

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  • IPEN-DOC 27051

    LOPES, HENRIQUE D.; NUNES, EDUARDO; COLOSIO, MARCO; ROSSI, JESUALDO . PM conversion study for a transmission component: scuffing wear ranking of nitrided Astaloy CrA and reference CQT 16MnCrS5 Rollers. In: WORLD PM2016 CONGRESS AND EXHIBITION, October 9-13, 2016, Hamburg, Germany. Proceedings... Chantilly, France: European Powder Metallurgy Association, 2016. p. 1-7.

    Abstract: Net shape manufacturing advantages and its cost effectiveness is well known for sintered structural parts for many automotive applications. Combined with cost effective material solutions, plus smart secondary processes, and finally leading to higher product performance, PM technology can add even more value to customer processes and end user applications. This paper describes the conversion study of a manual transmission component from wrought to pm steel, while presenting the results of comparing the wear performance when subjected to moderate forces and high sliding velocities. The authors analyzed the behavior of PM based Cr plus nitriding (gas or plasma) specimens in comparison with a wrought steel plus carburizing. The component lifetime and reliability was evaluated according to the IRG-diagram. The final conclusion is that the PM material has better wear performance than the current wrought steel component.

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  • IPEN-DOC 27048

    CARDOZO, NELSON X. ; OMI, NELSON M. ; AMBIEL, JOSE J. ; FEHER, ANSELMO ; NAPOLITANO, CELIA M. ; SOMESSARI, SAMIR L. ; CALVO, WILSON A.P. . Development of an irradiation system for radioisotope production applied to industrial process tomography. In: WORLD CONGRESS ON INDUSTRIAL PROCESS TOMOGRAPHY, 8th, September 26-29, 2016, Foz do Iguaçu, PR. Proceedings... International Society for Industrial Process Tomography, 2016.

    Abstract: Among the various applications of radioisotopes, the use of radiotracers is considered the most important in diagnosing operation and troubleshooting of industrial process plants in chemical and petrochemical companies. The radiotracers are used in analytical procedures to obtain qualitative and quantitative data systems, in physical and physicochemical studies transfers. In the production of gaseous radioisotopes used as tracers in industrial process measurements, argon-41 (41Ar) and krypton-79 (79Kr) have low reactivity with other chemical elements. 41Ar is a transmitter range with high-energy (1.29MeV) and a high percentage of this energy transformation (99.1%), resulting in relatively small quantities required in relation to the other, for an efficient detection, even in large thicknesses components. Nowadays, the production of gaseous radioisotopes in nuclear research reactors is performed in small quantities (batches), through quartz ampoules containing natural gas 40Ar or 78Kr. In this sense, the aim of this study is to develop an irradiation system for gaseous radioisotope production in continuous scale, applied in industrial applications of emission tomography and flow measurement. The irradiation system may produce 41Ar with activity of 7.4x1011Bq (20Ci) per irradiation cycle, through the Reactor IEA-R1 with 4.5MW and average thermal neutron flux of 4.71x1013 ncm-2s-1 to meet an existing demand in NDT and inspections companies, and even needed by the Radiation Technology Centre, at IPEN/CNEN-SP. The irradiation system consists of an aluminium irradiation capsule, transfer lines, needle valves, stripy connections, quick connectors, manometer, vacuum system, dewar, lead shielding, storage and transport cylinders, among other components. The irradiation system was approved in the leakage and stability tests (bubble test, pressurization, evacuation and with leak detector equipment SPECTRON 600 T). In the experimental production, alanine dosimeters were distributed into various components of the irradiation system, obtaining 1.07x1011Bq (2.9Ci) of 41Ar. In addition, exposure rates were determined in the lead shielding wall, in which the liquefied radioactive gas was concentrated, and in the storage and transport cylinders after 41Ar was transferred, by the portable radiation meter Teletector ® Probe 6150 AD-t/H.

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  • IPEN-DOC 27044

    KIM, HAE Y.; HARAGUCHI, M.I.; CALVO, W.A.P. . Comparison of industrial tomography algorithms for gamma scanning 2-D reconstruction. In: WORLD CONGRESS ON INDUSTRIAL PROCESS TOMOGRAPHY, 8th, September 26-29, 2016, Foz do Iguaçu, PR. Proceedings... International Society for Industrial Process Tomography, 2016. p. 1-7.

    Abstract: In this paper, we compare different industrial tomography algorithms to present the result of gamma scanning as a two-dimensional image of density distribution. In two-dimensional gamma scanning, an unconventional irradiation geometry is used and consequently many classic image reconstruction algorithms cannot be used. We tested two iterative reconstruction methods: ART (Algebraic Reconstruction Technique) and MART (Multiplicative Algebraic Reconstruction Technique). The iteration steps of both methods were intercalated with various filters: mean filter, median filter, anisotropic diffusion and total variation. The use of these filters greatly improves the quality of reconstruction. We report the obtained results.

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  • IPEN-DOC 27049

    SANTOS, RENATA S. da S.; SILVA, MARCOS P. de A.; HOELZEMANN, JUDITH J.; SILVA, CLAUDIO M.S. e; LANDULFO, EDUARDO ; LOPES, FABIO J. da S. . Study of cirrus clouds physical properties using the Lidar-DUSTER system and radiosounding data at Natal/RN- Brazil. In: ALBUQUERQUE, TACIANA T.A. (Ed.); ANDRADE, MARIA DE F. (Ed.); SANTOS, JANE M. (Ed.) AIR POLLUTION CONFERENCE BRAZIL; COMMUNITY MODELING AND ANALYSIS SYSTEM SOUTH AMERICA, 4th, July 22-24, 2019, Belo Horizonte, MG. Proceedings... Belo Horizonte, MG: SEAD, Treinamentos e Coaching, 2019. p. 355-360.

    Abstract: Cirrus clouds are classified as the highest clouds in the atmosphere occurring generally from 7 to 18 km, depending on the global region of appearance, and have necessarily ice crystals in their composition. They still have an uncertain influence role in climate, therefore are seen as important atmospheric elements to be studied. Lidar systems (LIght Detecting and Ranging) have shown efficiency in the collection of cirrus characteristics which can help in its better parameterization in climatic and atmospheric models. In this work a collection of physical characteristics of cirrus was carried out, for January and February of 2017 and 2018, at Natal’s atmosphere using Lidar DUSTER’s data (5.84 S 35.20 W), a partnership UFRN/IPEN-SP. Morphological patterns of that clouds have been observed according to its heights as well as variations. Clouds with thinner depths and tenuous are observed at the top regions of troposphere, around 16.0 km. Otherwise, clouds with bigger vertical extensions are found around 12.0 km. The height of occurrence of cirrus in Natal, for the considered period vary from a minimum height of 7.0 km to a maximum of 16.0 km. Cirrus clouds most frequently occurred at a medium height of 12.0 km, considering both years. Those clouds had a considerable representativeness over the city atmosphere corresponding to 67% of total Lidar measured days. Besides the Lidar system was also used data from radiosounding technique. The behavior of the meteorological variables such as relative humidity was analyzed for the regions in which were found cirrus by the Lidar DUSTER. Within the region limits was verified a significant increase of relative humidity values. This behavior is not observed in lower regions where there is not any clouds presence as well in a day without cirrus appearance. In addition, future analyzes of the potential equivalent temperature profile will be studied in order to verify the effect of the cirrus clouds occurring in the temperature and humidity profile in a combined manner. Also, is expected to evaluate the possible impacts of cold air intrusion of the stratosphere in layers of cirrus clouds. In conclusion, Lidar DUSTER data demonstrates to be efficient in the identification of cirrus clouds over Natal’s atmosphere contributing to a better comprehension of its behavior and role in the region of study.

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  • IPEN-DOC 27047

    RAE, CRISTINA T.S.; HOELZEMANN, JUDITH J.; OLIVEIRA, DANIEL C.F.S.; SILVA, MARCOS P.A.; LOPES, FABIO J.S. ; LANDULFO, EDUARDO . Atmospheric aerosol behavior study in Natal city through LIDAR backscatter profiles and random errors propagation analysis by Monte Carlo method. In: ALBUQUERQUE, TACIANA T.A. (Ed.); ANDRADE, MARIA DE F. (Ed.); SANTOS, JANE M. (Ed.) AIR POLLUTION CONFERENCE BRAZIL; COMMUNITY MODELING AND ANALYSIS SYSTEM SOUTH AMERICA, 4th, July 22-24, 2019, Belo Horizonte, MG. Proceedings... Belo Horizonte, MG: SEAD, Treinamentos e Coaching, 2019. p. 328-330.

    Abstract: The physical and optical interaction of aerosols in atmospheric processes are complex and have high temporal and spatial variability, representing uncertainties as, for example, the aerosol particles influence on the atmosphere energetic balance. The Duster is a LIDAR system (Light Detection and Ranging) located in Natal / RN, capable of working with four detection channels (355 nm, 532 nm p, 532 nm s and 1064 nm). Duster sends pulses of laser light to the atmosphere and detects the return signal that results from the interaction of light with aerosol particles in the atmosphere. The signal detected by the system is represented by the LIDAR equation, which describes the optical properties and the system geometric parameters. The solution for this equation is obtained by the Klett-Fernald-Sasano Inversion Method (KFS), which extracts the inverted optical properties as backscattering (β) and extinction (α) profiles. The present work brings the result of analysis in backscatter profiles of the LIDAR signal in channel 532 nm during the aerosol Monitoring Campaign Long-Range Transportation Over Natal II (MOLOTOV II) that occurred from November 2017 to February 2018. We applied the Monte Carlo method for the analysis of the error in DUSTER measurements, which employs random numbers sequences. Two days of signal measurements were selected, to deal with four groups files, within approximately 30 min each group (frequency acquisition every 10 seconds). N synthetic profiles, as height function, with a random number generator, were created. Algorithms were performed, which removed the measurements clouds, the dark profiles, the background noise and generated the Range Corrected Signal (RCS). The KFS was applied to the synthetic profiles to obtain a set of N solutions (backscatter and extinction coefficient profiles). The results show that the N optical property profiles presented a considerable variability, characterized by their standard deviation. This variability, calculated as the height function, is the random error estimate of the LIDAR signal associated with the inversion procedure. The observed aerosols, according to information from the Hysplit trajectory model, were originated from the Sahara desert.

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  • IPEN-DOC 27046

    OLIVEIRA, DANIEL C.F. dos S.; HOELZEMANN, JUDITH J.; LANDULFO, EDUARDO ; ALADOS-ARBOLEDAS, LUCAS; GUERRERO-RASCADO, JUAN L.. Aerosol optical properties in the atmosphere of Natal/Brazil by an AERONET network Sun-photometer. In: ALBUQUERQUE, TACIANA T.A. (Ed.); ANDRADE, MARIA DE F. (Ed.); SANTOS, JANE M. (Ed.) AIR POLLUTION CONFERENCE BRAZIL; COMMUNITY MODELING AND ANALYSIS SYSTEM SOUTH AMERICA, 4th, July 22-24, 2019, Belo Horizonte, MG. Proceedings... Belo Horizonte, MG: SEAD, Treinamentos e Coaching, 2019. p. 319-324.

    Abstract: The study of atmospheric aerosols contributes to the understanding of radiative forcing and global warming. In addition, aerosols may influence atmospheric chemistry, visibility, precipitation and human health. Since 2016, Natal (capital of Rio Grande do Norte, Brazil) has a Sun-photometer (CIMEL) of the RIMA-AERONET network that can identify the presence of biomass burning aerosols and desert dust from Africa. For this identification, it is aimed to characterize the optical properties of these aerosols present in the atmosphere of Natal. The level 1.5 data (version 3) provided by AERONET provide information on some aerosol characteristics such as Aerosol Optical Depth (AOD), Ångström Exponent (α), Single Scattering Albedo (SSA), Asymmetry Factor (g), Complex Refractive Index (N) and Volume Size Distribution (VSD). The analysis period was from August 2017 to March 2018. Aerosols were classified according to global climatologies and their optical properties were described. In addition, backward trajectories were modeled using the HYSPLIT model (version 4.8) to identify the predominant air masses origins. Aerosols present in the atmospheric column of Natal showed monthly mean AOD (500 nm)in the range of 0.10 to 0.(representing ~40%), monthly means of α (440-670 nm)between 0.6 and 0.8 (representing 30%), bimodal VSD with dominant coarse mode, SSA (440 nm) about 0.80, real part around 1.500, imaginary part ranging from 0.0125 to 0.0437 and g above 0.74. The classification showed mixed (60.4%), marine (30.7%) and mineral dust (8.9%) aerosols. The backward trajectories identified that, in about 51% of the cases, are originated from Africa.

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  • IPEN-DOC 27042

    GRANDISOLI, C.L.; ANA, P.A. da; COSTA, M.M.; ZEZELL, D.M. ; LINS, E.C.. Viabilidade da transiluminação dental como técnica de imageamento das estruturas internas do dente. In: CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 24., 13-17 de outubro, 2014, Uberlândia, MG. Anais... Bauru, SP: Canal 6, 2014. p. 2070-2073.

    Abstract: A Transiluminação Dental (TD) é uma técnica utilizada para obtenção de imagens das estruturas dos dentes que funciona através da detecção da radiação infravermelha transmitida através dos mesmos. Este trabalho visa apresentar a TD como técnica de imageamento das estruturas anatômicas internas do dente. Amostras de 16 dentes humanos foram divididas em grupos com espessuras entre 0.5 e 2.5 mm. Para captação das imagens foi utilizada uma câmera FPA InGaAs (900- 1700 nm; Xenics, Inc., Bélgica) e uma fonte de lâmpada halógena no infravermelho próximo (Ocean Optics, Inc., USA); além de filtros ópticos de 1000±10nm, 1100±10nm, 1200±10nm e 1300±50nm. Imagens foram capturadas para diferentes tempos de exposição do sensor da câmera. Os melhores resultados revelam a viabilidade de imageamento de estruturas de espessura de até 2,5 mm sem a utilização de filtros. Após a obtenção destes resultados, um experimento piloto foi realizado em mais 4 amostras de dentes íntegros a fim de detector a câmara pulpar dos dentes. Os resultados provaram a viabilidade da TD no imageamento dental.

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  • IPEN-DOC 27039

    GONÇALVES, KARINA de O.; SILVA, MONICA N. da; SICCHIERI, LETICIA B. ; SILVA, FLAVIA R. de O. ; COURROL, LILIA C. . Síntese verde de nanopartículas de ouro e aplicações no diagnóstico e terapia de aterosclerose. In: CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 24., 13-17 de outubro, 2014, Uberlândia, MG. Anais... Bauru, SP: Canal 6, 2014. p. 1874-1877.

    Abstract: As nanopartículas de ouro apresentam inúmeras aplicações na medicina, como por exemplo, a terapia fototérmica e o rastreamento de tumores (biomarcadores). Elas também podem ser utilizadas no transporte de drogas (drug delivery), genes e DNA. Foi recentemente demonstrada na literatura que a incorporação de nanopartículas de ouro na estrutura do ácido δ - aminolevulínco (ALA) melhora as propriedades fotodinâmicas da terapia. Neste estudo propomos estabelecer correlações entre alterações nas fluorescências da protoporfirina IX extraídas do sangue e o crescimento da placa de ateroma. Este estudo implica em determinar se as nanopartículas de ouro sintetizadas com ALA podem fornecer informações adicionais e permitir prever quais pacientes correm maiores riscos de doença cardíaca no futuro de forma não invasiva e de baixo custo.

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  • IPEN-DOC 27038

    SILVA, MONICA N. da; SICCHIERI, LETICIA B. ; SILVA, FLAVIA R. de O. ; GONÇALVES, KARINA de O.; ANDRADE, MAIRA F. de ; LANZONI, VALERIA P.; COURROL, LILIA C. . A análise da fluorescência do sangue de coelhos submetidos à dieta hipercolesterolêmica. In: CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 24., 13-17 de outubro, 2014, Uberlândia, MG. Anais... Bauru, SP: Canal 6, 2014. p. 1632-1635.

    Abstract: A aterosclerose é uma doença degenerativa crônica caracterizada pela presença de lesões com aspectos de placas ou ateromas em artérias de médio e grande calibre. É a causa primária de doenças cardiovasculares e infarto, que por sua vez representam a principal causa de morte por doença no mundo. Este estudo busca um potencial marcador de aterosclerose o que pode viabilizar um método diagnóstico minimamente invasivo e de baixo custo. Neste estudo coelhos da raça New Zeland foram submetidos à dieta hipercolesterolêmica. Em um primeiro estudo foram realizadas extrações do sangue e das artérias. Foi realizado o perfil metabólico dos coelhos após 20, 40 e 60 dias do início da dieta. As artérias excisadas foram analisadas por microscopia para verificação da instalação do processo aterosclerótico nos coelhos. No segundo experimento realizou-se a coleta de fezes semanalmente. Nosso objetivo foi à verificação das variações da quantidade de PPIX (protoporfirina IX) no sangue e nas fezes com o estadiamento da aterosclerose. Com as fezes obteve-se uma curva de calibração para a determinação da melhor quantidade de massa fecal para o melhor volume de acetona, para a extração da PPIX. O melhor resultado foi obtido com os valores 0,10 g de massa fecal para 400 microlitros de acetona. O estudo da extração da PPIX tanto no sangue e nas fezes mostrou o aumento da emissão de fluorescência da PPIX no grupo da indução hipercolesterolêmica, acompanhando o aumento dos valores de LDL (lipoproteína de baixa densidade). Este estudo identificou um potencial marcador de aterosclerose.

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  • IPEN-DOC 27026

    PEREIRA, T.M. ; DIEM, M.; BIRD, B.; MILJKOVIC, M.; ANA, P.A.; BACHMANN, L.; ZEZELL, D.M. . Caracterização por espectroscopia no infravermelho de colóides tireoidianos sadios e hiperplásicos. In: CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 24., 13-17 de outubro, 2014, Uberlândia, MG. Anais... Bauru, SP: Canal 6, 2014. p. 1115-1118.

    Abstract: O presente trabalho mostra a caracterização da Tiroglobulina contidos nos colóides tireoidianos por espectroscopia no infravermelho. A produção da tiroglobulina é alterada em pacientes com Bócio Nodular. Assim, as informações bioquímicas desta glicoiodoproteina podem ser utilizada como indicador desta disfunção. Os resultados utilizando espectroscopia no infravermelho revela diferenças bioquímicas nas conformação da proteína, hormônios e carboidratos.

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  • IPEN-DOC 27036

    PEREZ, CLARICE F.A.; SAHYUN, ADELIA ; FREITAS, KENIA A.M.. Study on the protection planning actions and response to nuclear or radiological emergency. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 1783-1787.

    Abstract: Nuclear or Radiological emergencies can have as a consequence the rise of Deterministic effects, in the population involved, and/or Stochastic effects due to their doses. In these situations, protective actions need to be done in order to keep the doses in the affected population below the levels of deterministic effects and protective actions that might reduce the risk of stochastic effects should be adopted, minimizing the doses to reasonably achievable levels. This work presents a comparative study between the publication of IAEA Safety Series 109 and the document of the International Atomic Energy Agency GSG-2 "Criteria for Use in Preparedness and Response for a Nuclear or Radiological Emergency" regarding the effective dose value system to be used as a basis to trigger protection actions in the Planning and Response to Nuclear or Radiological Emergencies that can reduce the risk of stochastic effects.

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  • IPEN-DOC 23677

    CARNEIRO, J.C.G.G. ; ALVES, A.S. ; SANCHES, M.P. ; RODRIGUES, D.L. ; LEVY, D.S. ; SORDI, G.M.A.A. . Basic characterization of a radioactive facility and evaluation of risk agents. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 892-899.

    Abstract: This is an exploratory and descriptive study with qualitative and quantitative approaches to investigate the basic characterization of a Brazilian radioisotope production facility through ample knowledge of the workplace, workforce, task performed and identification of present risk agents in labor environment. The studied sample was composed by 102 workers distributed in eight work processes. Data were collected from April 2013 to July 2014 by applying questionnaire forms and complemented by interviews and observations. The descriptive statistical analysis included ANOVA test and non-parametric tests, among others. For the purpose of this study, there was adopted a significance level of 5% (p<0.05). The analysis of socio-demographic variables demonstrated that male gender predominated in total sample (74.5%) and the mean age of the workers was (51.8 ± 1.7) years. The largest percentage of the responders (70.6%) was technician-level workers. Regarding task-related exposure, there was considered that all groups presented the same exposure profile. At the workplace, there were identified 17 risk agents, including physical, chemical, biological, ergonomic and accident risks. The workforce was categorized into 3 risk groups according to relative frequency distribution of the occupational risks. Among the sixteen qualitative variables studied at the workplace, only three of them did not demonstrate relative frequency. The only variable that showed association with the three risk groups was the possibility of the contact with ionizing radiation. The study provided an overview of the perception of occupational risk at the facility. According to the results obtained by statistical analysis, most of the qualitative variables presented statistically significant association (p<0.001) related to the occurrence of occupational risks. Even though the workers may be potentially exposed to different risk agents, the ionizing radiation was the main physical risk factor observed in this facility.

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  • IPEN-DOC 27063

    SORDI, GIAN M. . Comments on the General IAEA Safety Requirements - Part 3 - and suggestions for the next publications. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 381-383.

    Abstract: The international recommendations in question are described 52 requirements specified from chapter 2 to 5. The first chapter states that the number of fundamental safety principles has been increased form 3 to 10. To implement these requirments, the IAEA mentions 14 main parties but it is not clear which party is responsible for each of the fundamental safety principles. Chapter 2 presents 5 general requirements for protection and safety and makes it clear the responsibilities and competence of the government and regulatory body. ; but the responsibilities and competence of the other 12 principal parties reported in requeriment 4 are not clear. Chapter 3, which includes 37 requirements, is the most extensive and deals with planned exposure situations. Due to its extension, chapter 3 is left for a future paper, in case my comments are considered of some value by the principal parties involved. Chapter 4, with 4 requirements, deals with emergency exposure situations; and in chapter 5, the 6 requirements are about existing exposure situations. As to the requirements exposed in chapters 1, 2, 4 and 5 I have verified that the responsibilities and competence of the government and the regulatory body are clearly specified, which is not true for the other 12 principal parties. It is concerning this specific matter that I have made comments and suggestions. I also discuss the matters that are not under the responsibility of the radiological protection services but of other parties. Could the radiation protection service as a whole or in part be delegated to others, including the attributions of registrants or licensees?

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  • IPEN-DOC 27062

    SORDI, GIAN M. . Comments on the General IAEA Safety Requirements - Part 3 - and suggestions for the next publications. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 298-303.

    Abstract: The international recommendations in question are described 52 requirements specified from chapter 2 to 5. The first chapter states that the number of fundamental safety principles has been increased form 3 to 10. To implement these requirments, the IAEA mentions 14 main parties but it is not clear which party is responsible for each of the fundamental safety principles. Chapter 2 presents 5 general requirements for protection and safety and makes it clear the responsibilities and competence of the government and regulatory body. ; but the responsibilities and competence of the other 12 principal parties reported in requeriment 4 are not clear. Chapter 3, which includes 37 requirements, is the most extensive and deals with planned exposure situations. Due to its extension, chapter 3 is left for a future paper, in case my comments are considered of some value by the principal parties involved. Chapter 4, with 4 requirements, deals with emergency exposure situations; and in chapter 5, the 6 requirements are about existing exposure situations. As to the requirements exposed in chapters 1, 2, 4 and 5 I have verified that the responsibilities and competence of the government and the regulatory body are clearly specified, which is not true for the other 12 principal parties. It is concerning this specific matter that I have made comments and suggestions. I also discuss the matters that are not under the responsibility of the radiological protection services but of other parties. Could the radiation protection service as a whole or in part be delegated to others, including the attributions of registrants or licensees?

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  • IPEN-DOC 23678

    LEVY, DENISE S. ; SORDI, GIAN M.A.A. ; RODRIGUES, DEMERVAL L. ; CARNEIRO, JANETE C.G. . Enhancing communication on Radiological Protection throughout Brazil. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 284-290.

    Abstract: This paper focus on the potential value of Information and Communication Technologies (ICTs) to enhance communication on Radiological Protection throughout Brazil. The servers processing power added to the technology of relational databases allow to integrate information from different sources, enabling complex queries with reduced response time. It is our objective to provide radioactive facilities a complete repository for research, consultation and information on radiological protection in an integrated and efficient way. This webbased project works informatization of Radiological Protection Programs according to the positive tree published by AIEA in its Safety Series No. 102, the most generic and complete tree for an appropriate and effective radiation protection program. Up to this moment, the website counts on concepts, definitions and theory about optimization and monitoring procedures, interrelating information, currently scattered in various publications, in order to meet both Brazilian and international recommendations. The project involves not only the collection and interrelationship of existing information in the several publications, but also new approaches from some recommendations, such as potential exposures. Only few publications develop expressively the issue and, even though they provide fundamental theory, there is still lack of knowledge of failure probabilities, which currently constitutes a broad research field in radiological protection. This research proposes the development of fault trees and the analysis of different scenarios, suggesting paths to quantify probabilistically the occurrence of potential exposures, as well as probabilities to reach a certain level of dose. It is our target to complete the system in a near future, including other relevant issues, such as safe transport of radioactive materials, emergency response, radioactive waste management and decommissioning, among others. We believe the use of information technology for the radiological protection programs shall contribute greatly to provide information to Brazilian radioactive facilities throughout the country, spreading information to as many people as possible, minimizing geographic distances and stimulating communication and development.

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  • IPEN-DOC 27060

    SAHYUN, ADELIA ; GHOBRIL, CARLOS N.; PEREZ, CLARICE F.; SORDI, GIAN M. . Some suggestions to adequate the IAEA Safety Standards Series No. 49 according to the General Safety Requirements Part 3 from IAEA. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 224-227.

    Abstract: At that time of publication SSR49 two exposure situations were considered, namely: practices and interventions, with Naturally Occuring Radioactive Material (NORM) being considered as intervention exposures but acknowledging that some natural sources can have exposures resulting from practices. In the Ba sic Safety Standards (BSS) the exposure situations have been categorised as planned, emergency and existing. These three situations necessitate an update of SSR No.49 since NORM fits in the existing situation, i.e one in which the doses already exist and should be reduced. To reduce the doses will create radioactive waste that must be either treated or stored. This scenario raises a problem of defining the dividing line between existing and planned situations. The point of transistion from one situation to the other needs to be clarified in order to establish the necessary controls for an existing situation whilst providing the necessary controls needed for the planned situation. For the latter planned situation several questions arise as to whether certain requirements can be exempted and under what circumstances. This paper will examine what the authors consider most important in more detail with some suggestions made for further consideration.

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  • IPEN-DOC 27050

    ARAUJO, ELAINE C. ; ANDRADE, IZABEL da S. ; MACEDO, FERNANDA de M. ; CORREA, THAIS ; SALANI, MARIA H.G. de A. ; COSTA, RENATA F. da; RAMOS, SERGIANA dos P.; MARQUES, MARCIA T.A. ; LOPES, DANIEL S.; GUARDANI, MARIA L.G.; LANDULFO, EDUARDO ; GUARDANI, ROBERTO. Correlation study between air quality data and the Lidar system in Cubatao, Sao Paulo. In: SANTOS, JANE M. (Ed.); ANDRADE, MARIA de F. (Ed.); ALBUQUERQUE, TACIANA T.A. (Ed.) COMMUNITY MODELING AND ANALYSIS SYSTEM SOUTH AMERICA CONFERENCE, 3rd; AIR QUALITY CONFERENCE BRAZIL, August 28-31, 2017, Vitória, ES. Proceedings... Vitória, ES: Fundação Espírito-santense de Tecnologia, 2017. p. 175-177.

    Abstract: We present here the results of two methods with a scanning multiwavelength elastic lidar system and Beta Ray method (CETESB) realized in an industrial area. The objective is a comparer of these two methods to identify fixed sources of aerosol and to monitor plume dispersion. The results of the two aligned techniques indicate that can provide information on the concentration, spatial and temporal distribution of aerosol.

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  • IPEN-DOC 27009

    SANTOS, I.P. ; LEVY, D.S. . Produção de energia elétrica a partir de fontes nucleares: uma abordagem para estudantes do ensino médio. In: SIMPOSIO INTERNACIONAL SOBRE EDUCACIÓN, CAPACITACIÓN Y GESTIÓN DEL CONOCIMIENTO EN ENERGÍA NUCLEAR Y SUS APLICACIONES, November 22-26, 2015, Cusco, Peru. Proceedings... 2015.

    Abstract: This study reports a pedagogical experiment in high school classes, in a private school in São Paulo. The purpose of this experiment was to put students in touch with topics related to electric power generation from radioactive sources This project was developed with emphasis on the content available in an educational online portal, the site www.radioatividades.com.br. The site has been created in order to disseminate knowledge to children, adolescents, parents and teachers about the peaceful use of nuclear energy. The portal content is free to access and use for educational purposes. The project had three stages: initial dynamics on the subject with students, working with research groups, conducting short courses in the portal "radioatividades" and a final evaluation, which consisted in seminars prepared by students themselves. The first stage aimed to verify the previous knowledge that students had on nuclear energy, raising common prejudices that usually appear. The second phase of the project aimed to demystify some concepts, such as the insecurity linked to the use of atomic energy. For this research there were used reliable sources, as the site of the National Nuclear Energy Commission (CNEN), Institute of Radiation Protection and Dosimetry (IRD) and International Atomic Energy Agency (IAEA), as well as short courses offered by the portal "Radioatividades". To finish the project, the students formed groups and presented seminars for their classmates, with split topics, illustrative slides and post presentation time to answer questions. There were highly satisfactory results at the end of the project, performances with good theoretical foundation and valuable clarifications on nuclear energy.

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  • IPEN-DOC 27006

    GOULART, F. ; ICHIKAWA, R.U. ; TURRILLAS, X.; MARTINEZ, L.G. . Study on the microstructure of UNS S32304 duplex steel submitted to heat-treatments. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 45-48. DOI: 10.5151/phypro-viii-efa-12

    Abstract: Duplex stainless steels are characterized by a good combination of mechanical properties and corrosion resistance. Due to the metastable equilibrium between the ferritic (α) and austenitic (γ) phases, significant changes in the microstructure of these steels may occur when subjected to temperatures higher than the ambient, degrading their properties. In this work, it was investigated the influence of heat treatments on the microstructure and mechanical properties of a duplex stainless steel UNS-S32304. The heat-treatments were performed at four temperatures (300°C, 600°C, 900°C and 1000°C) with two treatment times (1 h and 6 h) and two processes of cooling down (in air and water). The samples were studied by X-ray diffraction using Pawley method to determine the lattice parameters, mean crystallite sizes and microstrain for the two phases and compared to Vickers microhardness results.

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  • IPEN-DOC 27005

    REIS, L.A.M. ; ALENCAR, M. ; GOMES, M.P. ; PEREIRA, L.A.T. ; MUCSI, C.S. ; ROSSI, J.L. . Study of recycling process viability of zirconium alloys chips for melting in VAR furnace. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 65-67. DOI: 10.5151/phypro-viii-efa-16

    Abstract: Cavacos de ligas de zircônio (M5, Zirlo, Zircaloy) são gerados em elevadas quantidades na confecção de tubos e tampões das varetas que compõem o elemento combustível de reatores de potência refrigerados a água pressurizada (PWR). Essas são ligas importadas e por isso é mostrado interesse pela indústria de reciclagem na sua reutilização. Este trabalho apresenta os estudos de um processo de reciclagem e a obtenção de eletrodos prensados para serem fundidos em um forno VAR (Vacuum Arc Remelting). O processo se inicia com uma separação magnética, lavagem do fluido de corte que é solúvel em água, utilização de um desengraxante industrial, seguido por um enxágue com fluxo contínuo de água em alta pressão e secagem por fluxo de ar quente. Para a obtenção de eletrodos, os cavacos foram prensados em uma matriz de seção quadrada 40x40 mm² com 500 mm de comprimento, resultando num eletrodo com 20% da densidade aparente da liga. A fusão foi feita um forno VAR de laboratório no CCTM-IPEN, gerando um lingote maciço de 0,8 kg. A fusão dos cavacos é possível e viável em um forno VAR o que reduz em até 40 vezes o volume de armazenamento desse material.

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  • IPEN-DOC 27004

    ABBADE, L. ; LARA, J.A.C. ; COUTO, C.P. ; GONSALEZ, B. ; COLOSIO, M.A.; ROSSI, J.L. . Resistance spot welding characterization of press hardened steel. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 10-13. DOI: 10.5151/phypro-viii-efa-03

    Abstract: In the automotive industry the resistance spot welding (RSW) is one of the most used processes for joining steel sheets, being of fundamental importance the quality assurance of this process. In this work, 22MnB5 steel sheets for the hot stamping process, also known as PHS (Press Hardening Steel), were joined by the technique of resistance spot welding, so that the welding parameters were changed 16 times for the evaluation of the influence of these parameters on the mechanical properties. By conducting ultrasonic, tensile and hardness test, followed by metallography, it was possible to identify the characteristics of the spot weld effect on the material. The results of the tests performed in this work confirmed the difference in mechanical strength of the thermal zone (ZTA) in relation to the molten zone (ZF). For a certain set of the parameters it was shown a decrease in the strength of the ZTA and increasing to the weld point, which is demonstrated in the microstructural analysis and thus justifies the detachment of the weld button of the base material during tensile testing, i.e., there was a higher strength in the welded area.

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  • IPEN-DOC 27003

    NASCIMENTO, J.O. do; PEREIRA, H.B.B.; MORET, M.A.; BARBOSA, L.P. ; TAKIISHI, H. . Redes semânticas em Ciências dos Materiais: uma aplicação da Teoria de Redes. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 116-121. DOI: 10.5151/phypro-viii-efa-27

    Abstract: Uma possibilidade de estudos em sistemas complexos corresponde a utilização da Teoria de redes sociais e complexas. Este artigo tem como objetivo descrever e analisar as redes semânticas baseadas nas palavras-chave dos artigos publicados nos anais do Congresso Brasileiro de Engenharia e Ciências dos Materiais (CBECiMat) referente ao ano de 2010. Alicerçamo-nos nas métricas de estatística básica pertencente às redes complexas, ao índice de centralidade de grau pertencente as redes sociais e apresentamos o método de construção das redes semânticas. As análises indicaram quais as palavras-chave se destacaram (por meio do número de suas conexões) e as topologias verificadas, sugerem redes livre de escala e mundo pequeno. Estes resultados auxiliam na escolha e observância de palavras-chave em futuros trabalhos nas áreas de ciências dos materiais e do evento (materiais cerâmicos, materiais compósitos, materiais metálicos, materiais poliméricos e ensino de materiais), bem como arguir sobre estratégias em mecanismos de busca de trabalhos científicos, tendo como descritores as palavras-chave.

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  • IPEN-DOC 27002

    GOMES, M.P. ; SANTOS, I.P. ; COUTO, C.P. ; BETINI, E.G. ; COLOSIO, M.A.; ROSSI, J.L. . Microstructural characterization of air quenched valve seat inserts obtained with AISI D2 tool steel. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 42-44. DOI: 10.5151/phypro-viii-efa-11

    Abstract: The obtention of valve seat insert (VSI) by powder metallurgy using a mixture of iron powder and tool steel is fulfilling the requirements for substitution of cobalt and lead in commercial parts, aiming cost reduction and avoid the lead toxicity. The aim of this work consisted of evaluate the influence of heat treatment on VSI obtained with AISI D2 tool steel powder. The AISI D2 tool steel powder was mixed with iron powder and additives such as manganese sulphide, zinc stearate, graphite and carbides. The heat treatment of the VSI consisted of air quenching followed by double tempering it at 500 °C. The microstructural characterization was performed using scanning electron microscopy and energy dispersive spectroscopy.

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  • IPEN-DOC 27001

    GOMES, M.P. ; SANTOS, I.P. ; REIS, L.A.M. ; CIONE, F.C. ; COLOSIO, M.A.; ROSSI, J.L. . Influence of air quenching on apparent hardness of valve seat inserts obtained with AISI M2 high-speed steel powder. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 39-41. DOI: 10.5151/phypro-viii-efa-10

    Abstract: The aim of this work consisted of evaluate the influence of heat treatment on sintered valve seat inserts (VSI) obtained with the AISI M2 high-speed steel powder. The AISI M2 high-speed steel powder was mixed with iron powder and additives such as manganese sulphide, zinc stearate, graphite and carbides. The heat treatment of the VSI consisted of air quenching followed by double tempering it in seven different equidistant temperatures, from 100 °C until 700 °C. The mechanical property was measured regarding the VSI apparent hardness. The results indicated that the VSI obtained with the AISI M2 high-speed steel powders mixtures showed the best results regarding its apparent hardness after air quenching and double tempering it at 600 °C.

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  • IPEN-DOC 27000

    BETINI, E.G. ; GOMES, M.P. ; REIS, L.A. ; MUCSI, C.S. ; ALENCAR, M.C. ; ORLANDO, M.T.D.; LUZ, T.S.; AVETTAND-FENOEL, M-N.; ROSSI, J.L. . Effect of the cooling rates on heat-affected zone of UNS S32304 duplex stainless steel welded by pulsed GTAW process. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 14-18. DOI: 10.5151/phypro-viii-efa-04

    Abstract: Two thin plates of UNS 32304 of duplex stainless steel were joined by pulsed gas tungsten arc welding (GTAW) using a mixture 98% of argon plus 2% of nitrogen as shielding gas or pure argon as purging gas at the bottom of the plate without filler metal. The temperature profile close and away from the weld pool was measured using K type (Ni-Cr) thermocouples, connected to a digital data acquisition system. The thermal cycles was recorded in the heat-affected zone (HAZ) at a distance in between 1 and 3 mm from the joint line. The cooling rate and holding time were studied with respect to the used purging gas. Experimental thermal profiles are in good agreement with literature values. The joints welded without any purging gas revealed high peak temperature and cooling rates. The present investigation showed that temperature peaks are comprised in the phase transformation temperature ranges for the welded duplex stainless steel.

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  • IPEN-DOC 26999

    PASCOATO, R. ; ARANHA, L.C. ; MUCSI, C.S. ; ROSSI, J.L. . Desenvolvimento de um torquimetro para medição dinâmica de microtorque. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 62-64. DOI: 10.5151/phypro-viii-efa-15

    Abstract: Foi desenvolvido um dispositivo protótipo de um torquímetro para ensaio de medição dinâmica de micro torques. Este dispositivo foi usado para a avaliação de implantes ortodônticos. O ensaio consistiu na inserção e retirada de pilares protéticos em implantes odontológicos, com torques menores que 100 Ncm. O principal componente desse protótipo foi a barra de torque, nesta, foi aplicado um extensômetro tipo strain gage. As deformações sofridas por este componente, não descriminavam entre deformações devido a tensões de flexão e tensões de torção. Com o propósito de diminuir esta sensibilidade a deformação por flexão e aumentar a sensibilidade da torção, foi proposta uma nova geometria para a barra de torque. Após ser estudada analiticamente, esta nova geometria mostrou- se bastante favorável quanto ao aumento da sensibilidade à torção do componente e a diminuição da interferência devido ao seu peso próprio.

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  • IPEN-DOC 26998

    SOUZA, A.C.; SILVA, A.C.; ROSSI, J.L. ; CIONE, F.C. . Analysis thermogravimetric of tungsten composite for gama radiaction shielding. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 36-38. DOI: 10.5151/phypro-viii-efa-09

    Abstract: The generation of Mo-99mTc generators for hospitals requires the transport of the Mo-99m material in containers with physicochemical properties for especially the shielding of gamma radiation [4, 5]. The application of tungsten alloys has been developed with the objective of minimizing the effects of radiation, being used in the manufacture of devices for the transport of radioactive material, considering its properties of specific mass (60% dense than lead), resistance corrosion, excellent absorption of high energy radiation and high mechanical strength [16,17]. The kraft lignin, a natural polymer obtained from the Kraft process of cellulosic pulp extraction, considered a residue of the cellulosic industry, can be used as a high adhesive material. The objective of this work was to perform the Thermogravimetric (TG), Differential Exploration Calorimetry (DSC) and X-ray diffraction (XRD) analyses of a new composite of tungsten and kraft lignin. The results showed the thermal and crystallographic properties of the composite, which could contribute to obtain a new material with ability to attenuate gamma radiation.

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  • IPEN-DOC 26997

    SOUZA, A.C.; ROSSI, J.L. ; FERNANDES, H.B.; GOUVEA, A.F.G.. Analysis of the microstructural evolution of composite of Tungsten with lignin kraft. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 76-78. DOI: 10.5151/phypro-viii-efa-19

    Abstract: In materials science and engineering, there is a demand in new materials for radiation shielding in the transport of radiopharmaceuticals used in the diagnosis and therapy of cancer, justifying the interest in developing this work. The obtained lignin kraft and tungsten form the precursors used for metal-organic composite. Tungsten metal has diverse applications in the nuclear sector presents an enormous mechanical strength and an excellent cross section with thermal neutrons. The aim of this study is to analyse the microstructural evolution of metal-organic composite using the kraft lignin and tungsten, using analysis of scanning electron microscopy (SEM), microhardness test and x-ray diffraction (XRD). Microscopic analysis showed the granulometry of the precursors separate and composite morphology, observing the formation of alpha (α) and beta (β) phases and absence of oxidation process for different heat treatment temperatures. The spectra of x-ray diffraction identified the structures of each phase formed and micro hardness measures showed an increase of mechanical resistance with temperature. The results of the microstructural characterization of metal-organic composite, will contribute in the next steps of attenuation measurements of gamma radiation.

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  • IPEN-DOC 26996

    COSTA, P.D.O.L. ; COSTA, I. ; COUTO, C.P. ; ROSSI, J.L. . Análise gravimétrica do revestimento de zinco-níquel de um aço 22MNB5 e zinco puro. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 29-31. DOI: 10.5151/phypro-viii-efa-07

    Abstract: O aço de alta resistência 22MnB5 é utilizado com revestimento de alumínio-silício com o objetivo de melhorar a resistência a corrosão e desgaste em peças expostas em meios molhados que favorecem o fenômeno corrosivo. Sua principal aplicação é no setor automobilístico englobando peças que integram a estrutura principal do veículo. Uma alternativa para a substituição do revestimento alumínio-silício é uma composição química do revestimento utilizando zinco-níquel. Neste trabalho foi estudado a evolução do processo de perda de massa em diferentes meios corrosivos (ácido, neutro e alcalino) identificando o comportamento do material revestido do aço 22MnB5 e comparando com zinco puro. Foram utilizados três variáveis: revestimento zinco-níquel como recebido, revestimento zinco-níquel estampado e zinco puro. Foi constatado que em meios ácidos (pH de 0 a 1) o processo de corrosão foi muito intenso para todos os materiais, do pH 3 ao pH 13 a perda de massa foi insignificante, mesmo sendo imersa durante dias, havendo a proteção do material pela camada passiva formada de óxido. O revestimento estampado se mostrou com maior tendência a perda de massa, por possuir mais defeitos em sua superfície facilitando o processo corrosivo enquanto que o revestimento como recebido se mostrou bem resistente.

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  • IPEN-DOC 26995

    RAMANATHAN, L.V. ; FERNANDES, S.M.C. ; CORREA, O.V. ; SOUZA, J.A. de ; ANTUNES, R.A.; OLIVEIRA, M.C.L. de. Coatings for safe long term wet storage of spent Al-clad research reactor fuels. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: SAFE MANAGEMENT AND EFFECTIVE UTILIZATION, November 16-20, 2015, Vienna, Austria. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2015. p. 1-8.

    Abstract: Pitting corrosion of the aluminium cladding of spent research reactor (RR) fuels in wet storage has been observed and the use of conversion coatings to protect the cladding was proposed. A coating prepared by conventional chemical processing as opposed to electrochemical processing is the only option due to constraints related to the shape of the fuel and its high radioactivity. Hence, hydrotalcite (HTC) and boehmite were considered. This paper presents: (a) preparation of hydrotalcite (HTC) coatings from different baths followed by post-coating treatments; (b) corrosion behavior of HTC coated AA 6061 alloy; (c) results of field studies in which uncoated and HTC coated AA 6061 alloy coupons and plates, the latter assembled as a dummy fuel element, were exposed to the IEA-R1 reactor spent fuel basin for extended periods. The laboratory and field tests revealed marked improvements in the corrosion resistance of HTC coated specimens, coupons and plates. The mechanism of corrosion protection is presented.

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  • IPEN-DOC 26994

    GOMES, M.P.; SANTANA, M.S.; ROSSI, J.L. ; POLITANO, R. . Estudo da energia mecânica necessária para a geração de pulsos mecânicos em uma barra de Kolsky. In: CONGRESSO CIENTÍFICO DA SEMANA NACIONAL DE CIÊNCIA E TECNOLOGIA NO IFSP, 6., 20-23 de outubro, 2015, Bragança Paulista, SP. Anais... Bragança Paulista, SP: Instituto Federal de São Paulo - Bragança Paulista, 2015.

    Abstract: A análise da resposta a pulsos mecânicos em materiais a serem utilizados em sistemas para transporte de substâncias radioativas é uma das condições para a sua respectiva seleção e dimensionamento. Para que se faça a caracterização da resposta dos materiais candidatos a este tipo de solicitação é necessária a construção de aparatos experimentais, sendo que neles é aplicado um pulso mecânico de forma controlada e com parâmetros conhecidos, possibilitando assim a obtenção das características mecânicas do corpo-de-provas - aparato este conhecido como barra de Kolsky. Uma parte crítica do aparato, é o alinhamento de todo o conjunto, pois o ensaio a ser realizado é considerado unidimensional. O menor desalinhamento irá causar distorções na onda mecânica de compressão, então os dados obtidos pela extensometria na superfície das barras não serão condizentes com a realidade. Portanto, o propósito deste projeto foi o de produzir um mancal que possibilitasse o alinhamento com uma maior precisão dos eixos x, y do aparato. Tal alinhamento será inicialmente feito manualmente, porém no dimensionamento e concepção do mancal foi reservado um espaço para o acoplamento de um servomotor, que futuramente irá ser utilizado para o ajuste preciso e automático do aparato.

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  • IPEN-DOC 26992

    FERREIRA, ALLANA C.P.; SANTOS, ELINALDO N. dos; MESQUITA, ARIMATEA P. de P.; ARAUJO, EDVAL G. de; GONZALEZ, CEZAR H.; AMBROZIO FILHO, FRANCISCO ; ARAUJO FILHO, OSCAR O. de. Endurecimento secundário do aço rápido AISI M3:2 nome comercial Sinter 23 produzido por uma técnica de metalurgia do pó / Secondary hardening of an AISI M3:2 high speed steel named Sinter 23 produced through powder metallurgy techniques. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 70.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALÚRGICA, DE MATERIAIS E DE MINAS,15., 17-21 de agosto, 2015, Rio de Janeiro, RJ. Proceedings... São Paulo, SP: Blucher Proceedings, 2015. p. 1755-1762.

    Abstract: O endurecimento secundário de aço rápido AISI M3:2 nome comercial Sinter 23 obtido por uma técnica de metalurgia do pó de sinterização por compactação isostática a quente é objeto desse trabalho de pesquisa. O aço rápido em questão foi austenitizado em banho de sal a 1.140°C, 1.160°C, 1.180°C e 1.200C, temperado ao ar e revenimento a 540°C, 560°C e 580C. Amostras do aço rápido foram fabricadas e submetidas ao tratamento térmico acima descrito e submetida a ensaios de dureza Vickers e Rockwell C para a determinação das suas respostas ao tratamento térmico de endurecimento e avaliação do pico de endurecimento secundário através dos resultados de dureza.

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  • IPEN-DOC 26991

    DEL BUSSO, NICOLANGELO; MONTEIRO, WALDEMAR A. . Caracterização microestrutural e mecânica de aço API-5L-X70 após soldagem pelo método de arco submerso / Mechanical and microstructural characterization in API 5L X70 steel after submerged arc welding process. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 70.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALÚRGICA, DE MATERIAIS E DE MINAS,15., 17-21 de agosto, 2015, Rio de Janeiro, RJ. Proceedings... São Paulo, SP: Blucher Proceedings, 2015. p. 1665-1674.

    Abstract: A soldagem é um processo industrial empregado na indústria do petróleo e em minerodutos devido ao sua excelente resistência mecânica. Os seus parâmetros provocam alterações metalúrgicas significativas no metal de solda. Neste trabalho foi estudado o aço microligado da classe API-5L-X70 em termos de microestrutura (metalografia e fratografia por microscopia óptica e eletrônica) e propriedades mecânicas (ensaio de tração a temperatura ambiente, dureza, dobramento e ensaio de impacto Charpy a – 20o C e a 0o C) após soldagem em arco submerso, nas regiões da zona fundida (ZF), zona termicamente afetada (ZTA) e metal de base (MB). O exame metalográfico apresentou microestrutura bandeada consistindo de ferrita poligonal, perlita e bainita, com pequeno tamanho de grão. Os resultados mostram o aumento da resistência mecânica influenciada pela presença de ferrita acicular. Análise fratografica apos ensaios mecânicos revelam comportamento dúctilfrágil.

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  • IPEN-DOC 26988

    GUERRERO-RASCADO, J.L.; ALADOS-ARBOLEDAS, L.; BENAVENT-OLTRA, J.A.; CAZORLA, A.; CHAMIZO, S.; FOYO, I.; GRANADOS-MUNOZ, M.J.; KOWALSKI, A.S.; OLMO, F.J.; PEREZ-RAMIREZ, D.; SERRANO-ORTIZ, P.; TITOS, G.; CASQUERO-VERA, J.A.; ORTIZ-AMEZCUA, P.; COSTA, M.J.; LOPES, F.J.S. ; LYAMANI, H.; PEREZ-PRIEGO, O.; PREISSLER, J.; MARTIN-TRIGO, O.. E-learning in the teaching-learning process at postgraduate level: application to geomet subjects. In: GOMEZ CHOVA, L. (Ed.); LOPEZ MARTINEZ, A. (Ed.); CANDEL TORRES, I. (Ed.) INTERNATIONAL CONFERENCE ON EDUCATION AND NEW LEARNING TECHNOLOGIES, 9th, July 3-5, 2017, Barcelona, Spain. Proceedings... Valencia, Spain: IATED Academy, 2017. p. 2699-2704. DOI: 10.21125/edulearn.2017.1561

    Abstract: This teaching innovation project arises from experience previously gained with other innovation projects encompassing several degrees with the aim of improving the academic performance of the students and the quality of teaching in several subjects of the Master’s program in Geophysics and Meteorology (GEOMET) at the University of Granada (Spain). Among other novelties, through this project resources have been developed for students to carry out an online self-assessment of their knowledge regarding contents of the different subjects through the Moodle platform, checking the level of skills acquired. In addition, the project includes a system of exchange of teaching, electronic resources between teachers and students (guides of subjects, viewgraphs, practical documents, among others). This platform has increased the coordination between the lecturers who teach the subjects.

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  • IPEN-DOC 26987

    MOREIRA, TATIANA M. ; SEO, EMILIA S.M. . Caracterização e utilização das fibras da casca da laranja como biossorvente na recuperação de corpos hídricos contaminados por derramamento de derivados do petróleo. In: CONGRESSO DA ASSOCIAÇÃO BRASILEIRA DE ENGENHARIA SANITÁRIA E AMBIENTAL; FEIRA NACIONAL DE SANEAMENTO E MEIO AMBIENTE, 2-6 de outubro, 2017, São Paulo, SP. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Engenharia Sanitária e Ambiental, 2017. p. 1-10.

    Abstract: Com base no desenvolvimento sustentável, este trabalho, visou buscar materiais tecnológicos com enfoque na reciclagem, onde se destacam as fibras vegetais, como as da laranja, que possuem baixo custo e impacto ao meio ambiente, com boa eficiência quando utilizadas para o processo de biossorção. Este método vem sendo utilizado como um recurso para redução de problemas ambientais causados por contaminação em corpos hídricos, como córregos e rios urbanos, por derramamento de substâncias tóxicas, minimizando assim os impactos dos ecossistemas aquáticos, bem como a contaminação do solo. A preparação destas fibras foi feita por meio de tratamentos físicos e químicos, tais como: lavagem, secagem, moagem, mercerização (tratamento químico com agente alcalino que ataca a superfície da fibra, melhorando suas características de sorção), classificação granulométrica e caracterização. Esses procedimentos geraram um material que pôde ser empregado como um biossorvente. Como contaminantes, foram utilizados derivados do petróleo, tais como a gasolina e o óleo diesel. Na caracterização foram utilizadas técnicas de: Picnometria, Termogravimetria, Análise Elementar, Microscopia Eletrônica, Fluorescência de Raios X, Teor de Umidade e Cinzas, Retenção de água, Hidrofobicidade e Flutuabilidade. Para os ensaios práticos foram mensuradas a sorção de contaminantes tanto em sistema seco, onde os contaminantes estão em contato direto com os biossorventes, quanto aquoso, simulando um derramamento de óleo diesel e gasolina em um corpo hídrico. Os resultados demonstraram que o biossorvente testado possui boa capacidade sortiva nos dois sistemas testados. Portanto, dada a sua origem renovável e de baixo custo, este material se mostrou eficiente para a finalidade proposta.

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  • IPEN-DOC 26986

    MILAGRE, MARIANA X. ; MACHADO, CARULINE S.C. ; ARAUJO, JOAO V. ; ASTARITA, ANTONELLO; PEBERE, NADINE; VIVIER, VINCENT; COSTA, ISOLDA . Intergranular corrosion susceptibility of Al-Cu-Li alloys. In: EUROPEAN CORROSION CONGRESS; INTERNATIONAL CORROSION CONGRESS, 20th; PROCESS SAFETY CONGRESS, September 3-7, 2017, Prague, Czech Republic. Proceedings... Frankfurt, Germany: European Federation of Corrosion, 2017.

    Abstract: In the present study, the intergranular corrosion (IGC) susceptibility of commercial Al-Cu-Li alloys of the third generation (AA2098-T351, AA2198-T3 and AA2198-T851) was compared with that of the AA2024-T3 alloy according to ASTM G110 test. In addition, anodic and cathodic polarization curves were carried out in the ASTM G110 test solution at room temperature. The cross-section of the samples after the ASTM G110 test was observed by scanning electron microscopy (SEM) to evaluate the extension of the corrosion attack. The susceptibility to intergranular attack of the tested alloys was ranked according to the attack by IGC and from the anodic and cathodic polarization curves. The results showed that the AA2024-T3 and the AA2198-T3 alloys presented higher susceptibility to intergranular corrosion comparatively to the other alloys tested (AA2098-T351 and AA2198-T851). The AA2098-T351 alloy was associated to the highest resistance to intergranular attack among the alloys evaluated. A correlation was seemingly established between the stress relief treatment of the alloy and its corresponding susceptibility to intergranular or intragranular corrosion.

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  • IPEN-DOC 26984

    ABREU, C.P. ; MELO, H.G. de; PEBERE, N.; MOGILI, N.V.V.; COSTA, I. ; VIVIER, V.. Corrosion resistance evaluation of the different zones on the AA2024-T3 and AA7475-T651 alloys welded by FSW. In: EUROPEAN CORROSION CONGRESS; INTERNATIONAL CORROSION CONGRESS, 20th; PROCESS SAFETY CONGRESS, September 3-7, 2017, Prague, Czech Republic. Proceedings... Frankfurt, Germany: European Federation of Corrosion, 2017. p. 1-14.

    Abstract: The aeronautic industry has a great interest in joining dissimilar aluminium alloys used in different parts of an aircraft. The Friction Stir Welding (FSW) process has been considered an effective alternative to conventional techniques for the welding of high strength alumin-ium alloys. However, this procedure results in zones with different microstructures due to thermal and thermomechanical effects involved during the joining process, leading to the formation of the thermomechanically affected zone (TMAZ), the heat affected zone (HAZ), the stir zone (nugget), and the unaffected base metal (BM). As the corrosion resistance of materials depends on their microstructures, the aim of this study was to investigate the intrin-sic corrosion resistance of the different zones of the AA2024-T3 and AA7475-T761 alloys welded by FSW, without considering the coupling effects between the different zones. This was achieved by evaluating the corrosion resistance of each individual zone in 0.1 M Na2SO4 + 1 mM NaCl solution by electrochemical techniques, such as open circuit potential meas-urements, polarization curves, and electrochemical impedance spectroscopy, using an elec-trochemical cell with an exposed area of 0.78 mm2. The electrochemical results showed that the lowest corrosion resistance was associated to the nugget zone, on which a galvanic cou-pling between the 2024 and 7475 alloys takes place. The corrosion resistance was also low-ered on the TMAZ of both alloys. This behaviour was associated to the enhanced precipita-tion of the η phase (MgZn2) at the grain boundaries in the 7475 alloy and to the coarsening of S phase (AlCuMg) precipitates in the 2024 alloy, both processes favoured by the thermome-chanical effects in these specific zones as demonstrated by TEM analysis.

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  • IPEN-DOC 26982

    FERREIRA, E.G. ; MARUMO, J.T. ; VICENTE, R. ; LANGTON, C.A.; DUNCAN, A.J.; WILLIAMS, M.R.. Test methods for cementitious seal materials for borehole disposal. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 43rd, March 5-9, 2017, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2017. p. 1-13.

    Abstract: The Nuclear and Energy Research Institute (IPEN-CNEN/SP) in Sao Paulo-Brazil, is considering borehole disposal of disused sealed radioactive sources (DSRS), which were used in smoke detectors, lightning arrestors, radiotherapy, industrial gauges, irradiators, and other applications. The current IPEN concept of borehole is a modified BOSS system developed by the International Atomic Energy Agency (IAEA). It differs from the IAEA’s design in that the disposal zone is below 300 m, and the DSRS are placed directly in the disposal packages constituted of stainless steel containers with 1.5 L capacity. A borehole drilled through sediment and granite, stabilized with stainless steel casing and cement grout is proposed for the conceptual model. Standard cement-material test methods and performance specific test methods, including accelerated aging methods, are needed for modeling the performance of the candidate cementitious grouts. A cross-disciplinary team from the USA Savannah River National laboratory is providing technical assistance to IPEN in this performance assessment.

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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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A pesquisa no RD utiliza os recursos de busca da maioria das bases de dados. No entanto algumas dicas podem auxiliar para obter um resultado mais pertinente.

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.