Eventos - Artigos: Recent submissions

  • IPEN-DOC 25299

    SEO, E.S.M. ; MOREIRA, T.M. ; SILVA, T.F.; ROCHA, T.F.O.; BARBOSA, I.T.F.; ATHIE, A.A.R.. Obtenção e caracterização de fibras vegetais para a preparação de biocompósito / Obtaining and characterizing vegetable fibers for the preparation of biocomposite. In: CONGRESSO BRASILEIRO DE ENGENHARIA E CIÊNCIA DOS MATERIAIS, 23., 04-08 de novembro, 2018, Foz do Iguaçu, PR. Anais... 2018. p. 2072-2083.

    Abstract: As atividades agroindustriais geram resíduos que, na maioria das vezes, não agregam nenhum valor comercial e não possuem destino apropriado para seu descarte. Porém, há possibilidade de tornar estes resíduos em matéria-prima para fabricação de produtos direcionados a aplicabilidade em diversos segmentos das indústrias. Neste contexto, o presente trabalho objetivou desenvolver o processo de obtenção das fibras de bambu, de cana-de-açúcar e da palha de milho, caracterizando-as para preparação do biocompósito. As fibras vegetais foram secas, trituradas, tratadas por mercerização e, em seguida, neutralizadas com solução ácida e lavadas em água corrente. A partir dos resultados de caracterização das fibras tratadas, observou-se que a lignina e a hemicelulose foram removidas, possibilitando melhor aderência das mesmas em contato com a superfície do polímero. Desta forma, o material compósito pode vir a ser reforçado com as fibras previamente tratadas por processo de mercerização.

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  • IPEN-DOC 25295

    SILVA, D.Y.B. ; REIS, S.L. ; MUCCILLO, R. ; MUCCILLO, E.N.S. . Espectroscopia de impedância da cerâmica Bi2/3Cu3Ti4O12 com permissividade elétrica gigante / Impedance spectroscopy of Bi2/3Cu3Ti4O12 ceramic with giant electric permittivity. In: CONGRESSO BRASILEIRO DE ENGENHARIA E CIÊNCIA DOS MATERIAIS, 23., 04-08 de novembro, 2018, Foz do Iguaçu, PR. Anais... 2018. p. 71-81.

    Abstract: Cerâmicas policristalinas com estrutura tipo perovskita são conhecidas por suas propriedades elétricas, como elevados valores de permissividade elétrica e baixas perdas dielétricas possuindo ampla faixa de aplicação tecnológica. Neste trabalho a cerâmica Bi2/3Cu3Ti4O12 (BCTO) foi obtida pelo método convencional de reação em estado sólido e suas propriedades elétricas e dielétricas foram investigadas por meio da técnica de espectroscopia de impedância, para diferentes temperaturas de medida, numa faixa entre 20 e 95°C. A evolução da permissividade elétrica, da tangente de perdas e do módulo elétrico em função da frequência na faixa 102-107 Hz foi estudada sistematicamente. Foram verificados três comportamentos de relaxação, indicando mudanças no mecanismo de polarização, relacionados com a interação da interface eletrodo-dielétrico e o mecanismo de condução de íons. Foram obtidos valores gigantes de permissividade elétrica (~ 2000) e baixas perdas dielétricas (~ 0,7) para uma ampla faixa de frequência. Foi feito também o estudo da condutividade elétrica intragranular resultando em energias de ativação de aproximadamente 0,2 eV, em concordância com o modelo IBLC (“Internal Barrier Layer Capacitance”).

    Palavras-Chave: ceramics; perovskite; spectroscopy; impedance; electrical properties; permittivity; electric conductivity; capacitance

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  • IPEN-DOC 25294

    BENVENUTTI, R.A. ; SILVA, A.A. ; LEITAO, F. ; GENOVA, L.A. . Efeito da dopagem com cobre e da temperatura de calcinação na capacidade de adsorção de 99Mo pela alumina. In: CONGRESSO BRASILEIRO DE ENGENHARIA E CIÊNCIA DOS MATERIAIS, 23., 04-08 de novembro, 2018, Foz do Iguaçu, PR. Anais... 2018. p. 20-30.

    Abstract: No Brasil ocorrem anualmente, aproximadamente 2 milhões de procedimentos de medicina nuclear, utilizando geradores de 99Mo/99mTc. A alumina utilizada na coluna destes geradores é determinante para o sucesso do mesmo, devendo adsorver e manter a máxima quantidade possível de 99Mo, e liberar o máximo de 99mTc, com o menor volume de eluente possível. Deve ainda permitir adequada permeabilidade e vazão do eluente sob vácuo, e ser quimicamente estável, não liberando íons Al3+ no eluente. Um dos principais limitadores para a produção de geradores de alta atividade é a quantidade de 99Mo adsorvido na alumina. Neste trabalho utilizou-se diferentes aluminas comerciais, tratadas termicamente entre 700 e 1000 ºC, e dopadas com Cu, visando aumentar a capacidade de adsorção do Mo e a eficiência de eluição do gerador.Aluminas com caráter ácido e com menor superfície específica adsorveram menor quantidade de Cu e de Mo.

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  • IPEN-DOC 25265

    SCAGLIUSI, SANDRA R. ; CARDOSO, ELIZABETH C.L. ; LUGAO, ADEMAR B. . Effect of gamma-radiation on thermal ageing of butyl rubber compounds. In: BRAZILIAN CONFERENCE ON COMPOSITE MATERIALS, 4th, July 22-25, 2018, Rio de Janeiro, RJ. Proceedings... 2018. p. 1-6.

    Abstract: Butyl rubber has a comprehensive use in sealing systems, especially in tires inner tubes, due to their low permeability to gases. So, it is required that butyl rubber compounds show a better performance, more and more. Butyl rubber is provided with excellent mechanical properties and oxidation resistance. Besides showing these properties, radiation exposures impart modifications in physical-chemical and morphological properties on butyl rubber materials. When exposed to gamma-radiation, rubbers suffer changes in their mechanical and physical properties, caused by material degradation. The major radiation effect in butyl rubbers is chain- scission; besides, ageing promotes too the same effect with further build-up of free radicals. This work aims to the study of gamma-radiation in physical-chemical properties of butyl rubber subjected to thermal ageing. Doses used herein were: 25 kGy, 50 kGy, 100 kGy, 150 kGy and 200 KGy. Samples were evaluated before and after ageing according to traditional essays, such as: hardness, tensile strength and elongation at break. From accomplished assessments it is possible to affirm that at doses higher than 50 kGy it was observed a sharp decreasing in butyl rubber physical-chemical properties, before and after exposure to ageing.

    Palavras-Chave: aging; gamma radiation; mechanical properties; physical properties; radiation effects; rubbers; vulcanization

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  • IPEN-DOC 25264

    MATTOS, C.E. ; SILVA, A.T.E. ; MARTINS, I.C. ; CARVALHO, E.F.U. de . Study of models for high burn behavior of uranium-7% gadolinium fuel rods for pressurized light water reactors. In: EUROPEAN RESEARCH REACTOR CONFERENCE, March 11-15, 2018, Munich, Germany. Proceedings... Brussels, Belgium: European Nuclear Society, 2018.

    Abstract: The objective of this work is to verify the validity of the results provided by the FRAPCON-3.5 software in the simulation of the behavior of the fuel UO2 - 7% by weight of Gd2O3, in order to evaluate the different models that are being proposed in codes of performance of fuels, in view of the behavior of fuel rods from PWR (Pressurized Water Reactor) under high burning conditions. To perform the analysis of the models that simulate the behavior of fuel pellets, the formation of the microstructure of (UO2-7% Gd2O3), fuel restructuring, temperature in the center of the fuel, comparison of the thermal conductivity between UO2 and the concentration of gadolinium as burnable venom, porosity in the restructured material, release of athermanous fission gases into the restructured material, release of thermally activated fission gases, including gas release models that occur due to grain growth. The results obtained in the computational simulations with the FRAPCON-3.5 program and its comparison with UO2 and UO2-7% Gd2O3, it will be possible to verify that the program has good capacity to predict the operational behavior of PWR fuel rods in permanent regime at high burns under transient condition initialized by reactivity.

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  • IPEN-DOC 25263

    MARUMO, JULIO T. ; ROBBINS, REBECCA A.; VELZEN, LEO V.; FERNANDO, KAPILA; ISEGHEM, PIERRE V.; KASHIWAGI, MAKOTO. International Network for Nuclear Waste Characterization (IAEA-Labonet) – Facts and Future - 18566. In: WASTE MANAGEMENT CONFERENCE, March 18-22, 2018, Phoenix, Arizona, USA. Proceedings... 2018. p. 1-7.

    Abstract: LABONET was launched early 2011 by the International Atomic Energy Agency (IAEA) as an International Network on nuclear waste characterization. Its objective is to improve the quality of, and harmonize, activities related to the radioactive waste characterization in IAEA Member States. It is widely accepted that proper characterization of radioactive waste through its entire flow-sheet is a key activity. In particular the needs and problems in radioactive waste characterization in the participating countries are a main concern within LABONET, as the programmes are not elaborated to the same level in the various countries. LABONET wants to facilitate the exchange of international experience in the application of proven, quality assured practices for the characterization of waste and waste packages. This will be beneficial for the less developed countries. The objectives of LABONET are achieved via different actions: a) exchanging information and expertise via presentations and discussions at technical meetings; b) expert meetings on particular topics of interest, for instance e-learning and e-platforms; c) training sessions in less developed countries, for instance, on non-destructive assay of waste packages; d) facilitate the exchange of information amongst its members ; and e) assist member states in establishing characterization plans that are cost effective and of good quality. LABONET is continuously encouraging Institutions or professionals who need some assistance or can help in solving questions about characterization to be a member. Currently, LABONET is preparing for its future, including projects addressing common problems of its members. Aiming at the dissemination of this important network for the professionals involved in radioactive waste characterization, this paper will discuss the following issues: (1) the objectives of LABONET, (2) its structure, membership and organization of meetings, (3) some achievements, and (4) plans for the future.

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  • IPEN-DOC 25262

    LANDULFO, EDUARDO ; GUARDANI, ROBERTO; MACEDO, FERNANDA M. ; COSTA, RENATA F. da; ARLEQUES, ANTONIO G.; KORENSKII, MIKHAIL; VESELOVSKII, IGOR. A novel lidar system for CH4 and VOC's detection of fugitive emissions and environmental monitoring. In: SINGH, UPENDRA N. (Ed.); TZEREMES, GEORGIOS D. (Ed.) LIDAR TECHNOLOGIES, TECHNIQUES, AND MEASUREMENTS FOR ATMOSPHERIC REMOTE SENSING, 14th, September 10-13, 2018, Berlin, Germany. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 107910B-1 - 107910B-6. (SPIE Proceedings Series, 10791). DOI: 10.1117/12.2324295

    Abstract: This study presents an overview of the recently results obtained by a novel concept of a lidar to remotely monitor methane and volatile organic compound including aerosols and fugitive gas emissions from pipelines, waste disposal areas and tankages. The system works based on Raman and uorescence scattering principles by emission of a 355 nm beam (3rd Nd:YAG harmonic) and detection of the wavelengths at 355 nm (elastic), 353 nm (oxygen + nitrogen rotational Raman) and 396 nm (methane vibrational Raman) and alternatively the system can be switched to a uorescence lidar based on a 32-channel PMT coupled to an spectrometer to be able to observe uorescence scattering caused by VOC's and aerosols. This paper shows a summary of the results obtained in the preliminary campaigns, which were carried out under di erent conditions to be adopted as benchmark for the system performance regarding detection limits, calibration capabilities, and time vs range resolution, in order to optimize the system performance.

    Palavras-Chave: methane; greenhouse gases; fluorescence; leak detectors; gases; emission; air pollution; air pollution control; pollution control equipment; optical radar; volatile matter; organic compounds; control systems

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  • IPEN-DOC 25258

    CASTRO, MICHELE C.B. de ; COUTO, ANTONIO A. ; ALMEIDA, GISELE F.C. ; MASSI, MARCOS; LIMA, NELSON B. de ; SILVA SOBRINHO, ARGEMIRO da; CASTAGNET, MARIANO ; XAVIER, GLEICY L. ; OLIVEIRA, RENE R. . Effect of plasma nitriding on fatigue behavior of Ti-6Al-4V alloy. In: INTERNATIONAL CONFERENCE ON ADVANCED COMPUTATIONAL ENGINEERING AND EXPERIMENTING, 12th, July 1-5, 2018, Amsterdam. Proceedings... 2018. DOI: 10.20944/preprints201812.0326.v1

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

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  • IPEN-DOC 25256

    BEU, CASSIA M.L. ; ESPINDOLA, FELIPE D.C.; LANDULFO, EDUARDO . Low-Level Jet observational study for the Brazilian Nuclear Reactor region. In: COMERON, ADOLFO (Ed.); KASSIANOV, EVGUENI I. (Ed.); SCHAFER, KLAUS (Ed.); PICARD, RICHARD H. (Ed.); WEBER, KONRADIN (Ed.) REMOTE SENSING OF CLOUDS AND THE ATMOSPHERE, 23th, September 10-13, 2018, Berlin, Germany. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 1078616-1 - 1078616-18. (SPIE Proceedings Series, 10786). DOI: 10.1117/12.2325476

    Abstract: A doppler wind lidar was employed to investigate the features of the Low-Level Jet (LLJ) at Ipero, Sao Paulo State, Brazil. The Ipero Municipality already host a nuclear facility for uranium enrichment and a new plant, a nuclear reactor, is planned to be built there. The nuclear activities require a good understanding of atmospheric dispersion, as for normal operation conditions as for accidental emissions. The LLJ is a natural phenomenon that may occur within the Planetary Boundary Layer and plays an important role for the atmospheric dispersion. Knowing the LLJ characteristics is essential to evaluate the performances of the weather forecast models that are used as input for the atmospheric dispersion models. The field campaign results showed that the LLJs occur with high frequency at Ipero and that the Stable Boundary Layer (SBL) is shallow, which in turn is unfavored for pollutant dilution because all surface emissions remain confined within the SBL. The 2 weather forecast models evaluated didn´t reproduce the LLJ, despite their high horizontal resolution. The numerical models also underestimated the wind speed. Both the LLJ and the wind speed are key parameters for dispersion simulations. As the weather forecast models diverge of the observational data, they must be better parameterized for provide reliable simulations before being adopted as input for any atmospheric dispersion models. The field campaign (planned to extend for 1 year) data are essential for the parameterization of the numerical models.

    Palavras-Chave: atmospheres; planetary atmospheres; wind loads; jets; fluid flow; boundary layers; brazil; dispersions; nuclear facilities; rmb reactor; isotope separation plants; atmospheric precipitations; meteorology

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  • IPEN-DOC 25024

    VIEIRA, A.; SAMAD, R.E. ; VIEIRA JUNIOR, NILSON D. ; ROSSI, WAGNER de . Ablação a laser com pulsos ultracurtos do aço DIN 16MnCr5: um estudo do processo de furação / Laser ablation with ultrashort laser pulses in steel DIN 16 MnCr5: a study of drill process. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICACAO, 9., 26-29 de junho, 2017, Joinville, SC. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2017.

    Abstract: A indústria automobilística tem como um de seus principais desafios, e consequentemente, foco de pesquisa, a redução do coeficiente de atrito entre alguns componentes e sistemas presentes nos automóveis. Um dos grandes benefícios dos avanços nesta área é o aumento da vida útil dos componentes e a melhor eficiência do motor. Desta maneira, uma das formas propostas pela tribologia para a redução de atrito é a texturização de superfícies por laser. Neste trabalho, foi abordada a interação de pulsos laser de femtossegundos com o aço DIN 16MnCr5, utilizado na indústria automotiva. Objetivou-se buscar os melhores parâmetros de processo para obter micro cavidades com pouca ou nenhuma zona afetada pelo calor e sem a presença de rebarbas e material ressolidificado, presentes na texturização com laser de pulsos longos (nanossegundos). Para a realização do estudo foi utilizada a técnica de escaneamento diagonal, D-Scan, para determinação dos limiares de ablação em função da sobreposição de pulsos. Também foram realizados estudos de formação das cavidades com a variação da posição do ponto focal e do perfil espacial do feixe laser. São apresentados resultados de análises obtidas por microscopia óptica e de varredura e interferometria de luz branca.

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  • IPEN-DOC 25026

    GOMES, MAURILIO P. ; SANTOS, IGOR P. dos ; COUTO, CAMILA P. ; MUCSI, CRISTIANO S. ; COLOSIO, MARCO A.; ROSSI, JESUALDO L. . Têmpera ao ar de insertos de assentos de válvulas obtidos com aço ferramenta AISI D2. In: CONFERENCIA BRASILEIRA SOBRE TEMAS DE TRATAMENTO TERMICO, 8., 21-24 de maio, 2017, Indaiatuba, SP. Anais... 2017.

    Abstract: A obtenção de insertos de assentos de válvulas por metalurgia de pó usando uma mistura de pó de ferro e aços rápidos ou aços ferramenta está atendendo os requisitos para a substituição do cobalto e chumbo em peças comerciais, visando a redução de custo e evitando a toxicidade do chumbo. O objetivo do presente trabalho foi o de tratar termicamente e caracterizar os insertos de assentos de válvulas sinterizados obtidos utilizando-se uma mistura de pós. Essa mistura de pós foi constituída pelo aço ferramenta AISI D2, ferro, sulfato de manganês, carboneto de nióbio, grafite, estearato de zinco e cobre. O ciclo de temperatura da têmpera ao ar foi determinado por meio do termopar tipo k acoplado a um sistema de aquisição de dados. As propriedades físicas e mecânicas foram medidas em relação à dureza aparente dos insertos, densidade aparente e a sua resistência à ruptura radial. A caracterização microestrutural foi realizada utilizando-se a microscopia óptica, microscopia eletrônica de varredura e espectroscopia por dispersão de energia. Os insertos temperados ao ar e duplamente revenido a 500 °C mostraram os melhores resultados no que tange a dureza e resistência à ruptura radial.

    Palavras-Chave: sintered materials; valves; machining; powder metallurgy; heat treatments

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  • IPEN-DOC 25022

    PERES, JOSE C.G.; HERRERA, CRISTHIANO da C. ; ROSSI, WAGNER de ; VIANNA JUNIOR, ARDSON dos S.. Analysis of a microreactor for synthesizing nanocrystals by computational fluid dynamics. In: WORLD CONGRESS OF CHEMICAL ENGINEERING, 10th, October 01-05, 2017, Barcelona, Spain. Proceedings... 2017.

    Abstract: A microreactor designed to synthesize nanocrystals was built applying laser pulses with duration of femtoseconds in a quartz board. This precise machining technology allowed dimensioning the microchip cross section as a trapezoidal shape with base lengths of 120 μm and 200 μm and depth of 150 μm. The microchip is comprised of four inlets for reactants, a mixing section with 40 curves after the inlet section to ensure proper mixing of the species and 22 serpentine channels, with 22,000 μm length each, to allow crystal growth. Flow field throughout the microchip was investigated by computational fluid dynamics considering inlet flow rates between 12.5 and 2000 μL min-1. Hexahedral meshes were used to discretize the geometry as its cross section is uniform and to reduce the total number of elements. Advection terms were solved by the high resolution scheme. Numerical solutions were converged when the maximum residual value was less than 10-4 and the domain imbalance was less than 1%. Flow throughout the channels is laminar as the maximum Reynolds number observed is 850. The tridimensional velocity profile is a paraboloid whose vertex is influence by the centrifugal force: at the curved sections, such force accelerates flow towards the outer part of the channels, moving the maximum velocity point to this zone. The centrifugal force also creates secondary flows. These structures enhance mixing in the direction perpendicular to the main flow and behave like turbulent flows in macroscopic systems, allowing proper mixing without additional power consumption. Proper coupling between microchip geometry and its operating conditions was verified by simulating the dispersion of a non-reactive tracer injected in one of the inlet ports while feeding the others with water. For low flow rates, the tracer flows parallel to the water stream up to half of the mixing section and full mixing occurs after the second serpentine channel. For flow rates higher than 250 μL min-1, it shows secondary fluxes are intensified and promote mixing after both the third curve at the mixing section and at the beginning of the serpentine channels after the fourth reactant inlet, ensuring better conditions if the desired reaction is limited by contact between the reactants.

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  • IPEN-DOC 25016

    BRASCHI, GIOVANI F.; EIRAS, JOSE A.; BARBOSA, PATRICIA A. ; ROSSI, WAGNER de ; CARNEIRO, MARCELO B. . Desenvolvimento de material em gradação funcional de metal duro e aço rápido para ferramenta de corte / Development of functionally graded material of cemented carbide and high speed steel for cutting tool. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICACAO, 9., 26-29 de junho, 2017, Joinville, SC. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2017.

    Abstract: Material em gradação funcional (Functionally Graded Material – FGM) tem sido considerado como uma nova classe de material, na qual materiais com propriedades distintas são unidos na forma de um gradiente, formando uma unidade estrutural com propriedades não uniformes. O objetivo deste trabalho é apresentar a caracterização de amostras em gradação funcional de metal duro e aço rápido. Para tanto, foram utilizados pós de metal duro (K20) e aço rápido (T6), que foram sinterizados por uma técnica comumente conhecida como SPS (Spark Plasma Sintering). A caracterização foi feita a partir da avaliação da microestrutura em microscópio laser confocal e eletrônico de varredura, determinação da densidade relativa pelo princípio de Arquimedes e avaliação do perfil de dureza Vickers ao longo seção transversal das amostras. Os resultados mostraram uma microestrutura com ausência de trincas de origem térmica, com maior valor de densidade relativa de 98,70% e com variação no perfil de dureza ao longo da espessura da amostra, o que evidencia propriedades não uniformes.

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  • IPEN-DOC 25021

    BARABAS, ROBERTA de C. ; SABUNDJIAN, GAIANE . The use of a neuroscience-based methodology to demystify and teach about the benefits of the nuclear field: neuroscience applied to nuclear energy teaching. 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: Science, technology and innovation play an essential role in helping countries increase the quality of life they offer their citizens. Since the discovery of nuclear fission in the 30s, the peaceful applications of nuclear technology have benefited several fields. Improved crops, preservation of food, health advance – specially for the diagnosis and treatment of cancer –, environment protection and a stable supply of energy can be cited as contributions of nuclear technology for global wellbeing. Despite its benefits the nuclear energy is still addressed with prejudice. Accidents in nuclear field have contributed for its negative image. Prejudice against nuclear energy lead to misconceptions on the theme, which interfere with authorities’ decision on the development of new nuclear technology. Education is the starting point for public acceptance of nuclear technology. Educational neuroscience is an emerging scientific field that explores the interactions between biological processes and education and helps identify and change implicit associations. This paper aims to demonstrate how the previous knowledge may interfere with the implicit associations towards a source of energy. The first steps of a neuroscience-based methodology in progress are presented in this paper: a) a pretest with specialists of the nuclear field; b) a subsequent test with lay subjects; and c) comparison of the results from the pretest and test. A future step consists of applying neuroscience principles to Brazilian science teachers to identify and modify implicit attitudes towards nuclear technology to promote an assertive teaching-learning process The global educational scenario has demonstrated absence of neuroscience-based methods for the nuclear technology teaching and that represents an opportunity for developing strategic teaching methods that will help demystifying the theme consequently improving public acceptance of this type of technology. Once the real scenario is demystified, the population will have a broad vision of all contributions of the nuclear field.

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  • IPEN-DOC 25018

    SANTAELLA, CESAR K.; PILLIS, MARINA F. . Effect of rare earth elements on the boronizing process. In: SENAFOR, 37th; INTERNATIONAL FORGING CONFERENCE, 21th; NATIONAL SHEET METAL FORMING CONFERENCE, 20th; INTERNATIONAL SHEET METAL FORMING CONFERENCE, 7th; BRDDRG CONGRESS, 4th; INTERNATIONAL CONFERENCE ON MATERIALS AND PROCESSES FOR RENEWABLE ENERGIES – BRAZIL/RS, 7th; INTERNATIONAL CONFERENCE ON SURFACE ENGINEERING IN MATERIAL FORMING, October 04-06, 2017, Porto Alegre, RS. Proceedings... 2017.

    Abstract: Boronizing is a thermo-chemical process consisting on the diffusion of the chemical element boron into metallic substrates, aiming at producing on the metal surface a closed layer of borides, which are elements extremely hard and chemically inert. Steels, for example, exhibit substantially higher hardness values (1,600 to 2,000HV) than nitrided steels (650 to 900HV) due to the formation of iron borides. The combination of high hardness and low friction coefficient of this boride layer greatly contributes to endure the main mechanisms of wear: adhesion, abrasion and superficial contact fatigue. The use of the boronizing process, however, is limited due to the elevated process temperatures. To overcome this limitation, recent studies pointed to the use of rare earth elements as catalysts of the process. This work will present the state of the art of these developments.

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  • IPEN-DOC 25017

    LAPA, NELBIA; MARTINS, LUIZ C.; MADEIRA, ALZIRA; WELLELE, OLIIVER; SABUNDJIAN, GAIANE; LEE, SEUNG ; STEINROTTER, THOMAS. Simulation of a station black out at the Angra 2 NPP with Melcor Code. In: TECHNICAL MEETING ON THE STATUS AND EVALUATION OF SEVERE ACCIDENT SIMULATION CODES FOR WATER COOLED REACTORS, October 09-12, 2017, Vienna, Austria. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2017.

    Abstract: The interest in evaluating the level of resistance of a nuclear power plant in response to an accident that exceeds the project bases, increased significantly after the Fukushima-Daiichi accident. Melcor is an integrated code, developed by Sandia National Laboratories, used to model and simulate the evolution of severe accidents in nuclear power plants. The Melcor modeling is general and flexible, making use of a “control volume” approach in describing the thermal hydraulic response of the plant. Reactor-specific geometry is imposed only in modeling the reactor core. The reactor cooling circuit and the four SG are represent by two model-loops, a single loop with the pressurizer and an agglutinated triple loop. All active safety systems which depend on AC power are assumed to be unavailable in this analysis. The most important strategies assumed were primary side depressurization and additional makeup water to reactor coolant system. The passive severe accident management measures primary bleed, secondary side bleed, passive injection from feedwater system and firefighting pool available. In Brazil there is the Almirante Álvaro Alberto Nuclear Power Plant that has two plants in operation, and one of them is Angra 2, which started operating in 2001. This unit is a pressurized water reactor type with electrical output of about 1350 MW. The objective of this work is to present a summary of the severe accident caused by a station black out condition using the Melcor 1.8.6 code. The main result of the study is an evaluation of RPV lower head integrity during a severe accidents scenario. The results will be useful to an independent assessment into the detailed processes involved by the management guidelines for one scenario severe accident in Angra 2.

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  • IPEN-DOC 25006

    BENTO, RODRIGO T. ; OLIVEIRA, EDUARDO C. de ; SZURKALO, MARGARIDA ; CORREA, OLANDIR V. ; PILLIS, MARINA F. . Characterization and photocatalytic behavior of TiO2 thin films grown by MOCVD process. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, November 27-30, 2017, Guarujá, SP. Proceedings... 2017.

    Abstract: This research aims to evaluate the influence of the thickness on the photocatalytic behavior of TiO2 thin films grown at 400ºC by metalorganic chemical vapor deposition. Titanium dioxide films with 280 and 468 nm of thickness were grown on borosilicate substrates. The photocatalytic behavior was evaluated by monitoring the degradation of methyl orange dye under UV light for 2h. The results show that both films presented anatase crystalline phase and that increasing the thickness the grain size and the roughness were also increased. The best photocatalytic performance was attributed to the film of 468 nm of thickness that exhibited 40% of dye degradation after 2h under UV light.

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  • IPEN-DOC 25005

    SZURKALO, MARGARIDA ; OLIVEIRA, EDUARDO C. de ; CORREA, OLANDIR V. ; BENTO, RODRIGO T. ; PILLIS, MARINA F. . Synthesis and characterization of TiO2 films obtained by sol-gel method. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st, November 27-30, 2017, Guarujá, SP. Proceedings... 2017.

    Abstract: Borosilicate coated titanium dioxide thin films were produced by the sol-gel method. The films were calcinated at 450°C for 20 minutes for crystalization. X-ray diffration analyses show that before the heat treatment the film was amorphous and after that it crystallized in anatase phase presenting mean grain size of 34 nm and RMS roughness of 8 nm. The crystallized film was used as photocatalist in the degradation of methyl orange dye presenting an efficiency of 25% after 2h under UV light.

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  • IPEN-DOC 25003

    IZIDORO, JULIANA de C. ; MIRANDA, CAIO da S. ; GUILHEN, SABINE N. ; FUNGARO, DENISE A. . Chemical, mineralogical and environmental characterization of combustion byproducts generated from mineral coal used for electricity production. In: INTERNATIONAL CONFERENCE ON MATERIALS CHEMISTRY, 13th, July 10-13, 2017, Liverpool, UK. Proceedings... Cambridge: Royal Society of Chemistry, 2017. p. 1-14.

    Abstract: The coal combustion by-products, bottom ash (BA), fly ash from cyclone filter (CA) and fly ash from bag filter (FA), generated in a Brazilian thermoelectric power plant, were characterized by Xray fluorescence, X-ray diffractometry and leaching and solubilization tests. The material retention systems used in the Brazilian power plant from where these by-produtcts were sampled are showed in Figure 1. The three types of coal ashes presented similar chemical composition, with a total content of main oxides (SiO2, Al2O3 and Fe2O3) above 72% and were classified as class F (according to ASTM). The analysis of ash enrichment factor showed that arsenic, zinc and lead concentrate mainly on FA, whereas the elements that presented the greatest enrichment in the bottom ash (BA) and therefore present low volatility are K and Mg. All ashes presented quartz, mullite and magnetite as crystalline phases. In the leaching and solubilization study, the FA sample was considered hazardous and classified according to Brazilian regulation as Class I solid waste, whereas CA and BA samples were considered non-hazardous and not inert solid wastes and classified as Class II-A. Therefore, FA sample from this Brazilian power plant must be discarded only after treatment or stringent disposal criteria must be followed to avoid contamination on site.

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  • IPEN-DOC 25002

    VEGA, O. ; LOPES, P.R. ; AMARAL, P.O. ; GONSCHOROWSKI, G. ; OLIVEIRA, J.P. ; FABBRO, R. ; MESQUITA, K.A. ; GIMENEZ, M.P. ; REDIGOLO, M. . Preparación de muestras del médio ambiente para análisis por médio de técnicas cromatograficas. In: SIMPOSIO LATINOAMERICANO DE QUIMICA ANALITICA Y AMBIENTAL, 12th, April 25-27, 2017, Manizales, Colombia. Proceedings... Bogotá, Colombia: Pontificia Universidad Javeriana, 2017.

    Abstract: Este artículo explora la ciencia de la preparación de muestras para matrices sólidas, líquidos y gases, utilizados en el laboratorio del Centro de Química y Medio Ambiente del IPEN. Extracción de neonicotinoides del agua por LLE (Liquid-Liquid Extraction), extracción de hidrocarburos aromáticos policíclicos (PAHs) del agua atraves de DLLME (Dispersive liquid - liquid micro extraction) y el uso de extracción en fase sólida SPE (Solid Phase Extraction) para el análisis de hormonas en agua son descritos. Limites de detección que utilizan estas técnicas son descritas en este trabajo.

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  • IPEN-DOC 25001

    LEVY, D.S. ; SORDI, G.M.A.A. ; RODRIGUES, D.L. ; CARNEIRO, J.C.G. . Information and communication technologies for appropriate communication in the workplace. In: CONGRESO REGIONAL DE SEGURIDAD RADIOLOGICA Y NUCLEAR, 11th, April 16-20, 2018, La Habana, Cuba. Proceedings... 2018.

    Abstract: Brazil is one of the 5th largest countries on earth. It is geopolitically divided into five regions, with large between-country distances and plenty of radioactive facilities throughout the country. Professional continuing education is a must and a challenge. This paper discusses a web-based project designed to provide effective communication about occupational exposure, using creative, innovative and practical Internet solutions to link geographically distant workers to high-quality reliable information. This web-based-project counts on concepts, definitions and theory about radiological protection issues, such as optimization programs and ionizing radiation monitoring procedures. Moreover, the content presents discussions related to national and international recommendations, such as potential exposure, which is currently one of the most important research fields in radiological protection. Only few publications develop expressively the issue and there is still lack of knowledge and uncertainties. Risk definition itself can assume different meanings, even among scientific community. To respond to this challenge, this project discusses potential exposures through question-and-answer topics addressing particular attention to effective actions towards safety which can be incorporated into labor practice in the workplace. For discussions to be effective, all content is based on ICRP and IAEA valid recommendations and official reports, in addition to scientific papers published in major international congresses. This project aims to provide radioactive facilities reliable updated communication, to inform as many people as possible, contributing to develop workers´professional skills and to improve safety culture in workplace.

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  • IPEN-DOC 25000

    LEVY, D.S. ; SORDI, G.M.A.A. ; RODRIGUES, D.L. ; CARNEIRO, J.C.G.G. . Information and communication about occupational exposure in workplace. In: SIMPOSIO INTERNACIONAL SOBRE PROTECCION RADIOLOGICA EN MEDICINA, August 20-24, 2017, Arequipa, Peru. Proceedings... 2017.

    Abstract: Medical applications of ionizing radiation are essential for protecting and improving human health. The radiological protection objective is to keep doses as low as reasonably achievable, maximizing dose reduction in order to obtain the necessary results for patients in diagnostic and interventional radiology, nuclear medicine and radiotherapy. There is plenty of information, published papers and studies about radiological protection for patients, regarding interventional radiology, nuclear medicine, radiotherapy, biomedical research, among others. Nevertheless, medical and paramedical personnel themselves are also exposed to radiological risks associated with the various uses of radiation in medicine. This paper discusses some considerations about radiological protection in workplace, as well as the need of more accurate information and communication about occupational exposure and potential exposures in medical practice. We believe that this type of information and communication will be helpful for exposed individuals knowingly while voluntarily helping - other than in their occupation - in the care, support or comfort of patients undergoing medical diagnosis or treatment and for visitors of the patients.

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  • IPEN-DOC 24999

    MANTECON, JAVIER G. ; MATTAR NETO, MIGUEL . One-way fluid-structure interaction model to study the influence of the fluid velocity and coolant channel thickness on the stability of nuclear fuel plates+. In: ABCM INTERNATIONAL CONGRESS OF MECHANICAL ENGINEERING, 24th, December 3-8, 2017, Curitiba, PR. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2017.

    Abstract: In nuclear research reactors, the fuel elements are frequently composed of parallel, flat or curved plates. A major problem of that fuel element configuration is the hydraulic instability of the plates caused by high coolant velocities. Thin plates contain the fuel and they are separated by narrow channels through which the coolant flows to remove the heat generated. In this study, a numerical analysis was conducted to examine the fluid-structure interaction of a flat fuel plate bounded by two coolant channels. The loads caused by the fluid flow are calculated using a Computational Fluid Dynamics model implemented in ANSYS CFX, and the plate structural responses are determined using a Finite Element Analysis model implemented in ANSYS Mechanical. The goal of the present work is to estimate the amount of deformation of a fuel plate when there is an increment of the fluid velocity and a variation in the thickness of the coolant channels.

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  • IPEN-DOC 24998

    SILVA, K.C. ; GUILHEN, S.N. ; IZIDORO, J.C. ; FUNGARO, D.A. . Removal of cadmium and zinc from aqueous solutions using zeolite synthesized from coal fly ash and industrial aluminium waste. In: ENCONTRO BRASILEIRO SOBRE ADSORCAO, 12., 23-25 de abril, 2018, Gramado, RS. Anais... 2018.

    Abstract: Coal fly ash can be used as a source of Silicon and Aluminum for 4A zeolite synthesis. It is necessary to consider the adequate proportion of Si / Al for the synthesis, so the aluminum waste from tertiary industry was used as an alternative and sustainable aluminum source. The synthesis was carried out by alkaline fusion followed by the hydrothermal treatment obtaining sodium aluminosilicate, which was then crystallized in NaOH solution. The samples were characterized by XRF, XRD and cation exchange capacity. The zeolite produced has the capacity to adsorb the Cd (II) and Zn (II) ions from aqueous solutions. The maximum adsorption capacity was 78.0 and 35.8 mg.g-1 for the Cd and Zn, respectively. The results showed that the aluminum waste and the fly ash together can be transformed into zeolite A, considered as value-added material and with promising adsorption properties.

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  • IPEN-DOC 24951

    OLIVEIRA, EDUARDO C. de ; SZURKALO, MARGARIDA ; CORREA, OLANDIR V. ; BENTO, RODRIGO T. ; PILLIS, MARINA F. . Morphological characterization of N-doped TiO2 thin films. In: PAN AMERICAN CONGRESS OF NANOTECHNOLOGY, 1st; FUNDAMENTALS AND APPLICATIONS TO SHAPE THE FUTURE, November 27-30, 2017, Guarujá, SP. Proceedings... 2017.

    Abstract: Metallorganic chemical vapor deposition was used to grown TiO2 and N-doped TiO2 on borosilicate substrates at 400°C. Titanium isopropoxide IV was used as titanium and oxygen precursors and ammonia as nitrogen source. Analyses by atomic force microscopy showed that both films presented rounded well-defined grains. The results showed that nitrogen doping resulted in a decrease in the mean grain size and in the surface roughness.

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  • IPEN-DOC 24950

    ALVES, ELIANE G.; TOTA, JULIO; TURNIPSEED, ANDREW; VEGA BUSTILLOS, JOSE O.W. ; SANTANA, RAONI A.; LOPES, PAULA R.C. ; CIRINO, GLAUBER G.; TAVARES, JULIA V.; LOPES, ALINE; NELSON, BRUCE; ROSA, DIOGO; VALE, DALTON; SOUZA, RODRIGO de; GU, DASA; STAVRAKOU, TRISSEVGENI; ADAMS, DAVID; WU, JIN; SALESKA, SCOTT; DIAS-JUNIOR, CLEO; YANEZ-SERRANO, ANA M.; KESSELMEIER, JURGEN; KARL, THOMAS; MANZI, ANTONIO; GUENTHER, ALEX. Seasonal changes in isoprene emission and deposition in central Amazonia. In: ILEAPS SCIENCE CONFERENCE, 5th, September 11-14, 2017, Oxford, UK. Proceedings... 2017.

    Abstract: Isoprene fluxes vary seasonally with changes in environmental factors as light and temperature, and biological factors as leaf phenology. But, our understanding of isoprene seasonal dependency to these factors is still limited in Amazonia. It has been indicated that the dry season shows higher emissions than the wet season, because there is more light available and higher temperature. Also, leaf phenology was recently suggested to drive ecosystem isoprene emissions, but local seasonal observations were scarce or not available. Here, we present canopy isoprene flux measured in two sites of primary rainforest in central Amazonia and compare to changes in light, temperature, and leaf phenology. The highest emissions were during the dry and dry-to-wet transition seasons, and the wet and the wet-to dry transition seasons revealed net deposition for one site. Leaf phenology, referred as changes in observed mature Leaf Area Index, was the most correlated factor and explained up to 59% of seasonal isoprene emissions. Attempting to represent this with modeling, the MEGAN 2.1 leaf age algorithm was driven by inputs resulted from a leaf demography64 ontogeny model that uses leaf flushing observed in the fields. However, model emissions were overestimated and did not capture the seasonal behavior observed. Using the leaf phenology from the field as inputs for the leaf age algorithm of MEGAN 2.1, improved estimates of the proportion of leaves in different leaf age categories for each site, but did not change the relative isoprene emission capacity used for each age class. This study hightlights the importance of accounting for differential isoprene emission capacity across canopy leaf age classes and of identifying the forest adaptive mechanisms that underly seasonal variation of emission, and potentially deposition, of isoprene in Amazonia.

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  • IPEN-DOC 24975

    WETTER, NIKLAUS U. ; SILVA, DANILO A.A. da ; JIMENEZ-VILLAR, ERNESTO ; GIEHL, JULIA M. . Influence of the fraction of absorbed pump power on the performance of Nd3+:YVO4 powder random lasers. In: JIANG, SHIBIN (Ed.); DIGONNET, MICHEL J.F. (Ed.) OPTICAL COMPONENTS AND MATERIALS, 15th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 105281U-1 - 105281U-8. (SPIE Proceedings Series, 10528). DOI: 10.1117/12.2290674

    Abstract: Understanding light absorption in random lasers and its distribution within the scattering gain media is a key issue to increase the lasers’ efficiency. Here we compare monodispersed and polydispersed powders of Nd3+:YVO4 and investigate the influence of the powder size distribution on scattering mean free path, absorption volume and, eventually, the lasers efficiency. The highest efficiency is achieved for polydispersed powders and we conjecture that these polydispersed powders, composed of pockets containing small grains trapped between large particles, present locally higher pump power densities than the monodispersed powders. We establish a figure of merit, based on measurable powder parameters, that agrees well with the obtained output power results of the monodispersed and polydispersed samples.

    Palavras-Chave: lasers; randomness; light scattering; neodymium lasers; yttrium compounds; scanning electron microscopy; powders; emission spectra

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  • IPEN-DOC 24974

    WAKASUGI, DENISE S.M. ; DAMATTO, SANDRA R. . Avaliação da concentração de 226Ra, 228Ra E 210Pb em águas minerais dos Parques das Águas de Lambari e Águas de Contendas – MG. In: CONGRESSO BRASILEIRO DE GEOQUIMICA, 16., 22-25 de agosto, 2017, Búzios, RJ. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Geoquímica, 2017.

    Abstract: A exploração de estâncias hidrominerais brasileiras que possuem fontes de água mineral radioativas, consumidas pela população que acredita nos benefícios da prática de tratamentos de saúde conduzidos por balneários, apesar da inexistência de comprovações científicas, fundamenta a relevância do estudo desenvolvido no Centro de Radiometria Ambiental com o auxílio dos responsáveis pelos balneários de Lambari e Contendas – MG. Assim, o estudo visa determinar as concentrações de atividade de 226Ra, 228Ra e 210Pb nas águas das fontes dos referidos parques e a influência da sazonalidade na concentração destes radionuclídeos. Para isso, foram analisadas amostras de duas estações do ano e a utilização das técnicas analíticas de alfa e beta total após separação radioquímica para a determinação desses radionuclídeos.

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  • IPEN-DOC 24973

    STELLATO, THAMIRIS B. ; SILVA, TATIANE B.S.C. da ; FAUSTINO, MAINARA G. ; MARQUES, JOYCE R. ; MIRANDA, GABRIELLE da S. ; OLIVEIRA, CINTIA C. de ; MONTEIRO, LUCILENA R. ; PIRES, MARIA A.F. ; COTRIM, MARYCEL E.B. . Avaliação de águas subterrâneas no estudo de recursos hídricos na área de instalação do futuro Reator Multipropósito Brasileiro – RMB. In: CONGRESSO INTERNACIONAL DA REDE DE SANEAMENTO E ABASTECIMENTO DE AGUA, 3., 11-15 de setembro, 2017, Belo Horizonte, MG. Anais... São Paulo: Rede de Saneamento e Abastecimento de Água, 2017.

    Abstract: A proposta deste estudo é avaliar as características químicas das águas subterrâneas da área de instalação do futuro Reator Multipropósito Brasileiro (RMB), como uma ferramenta para o processo de licenciamento ambiental. Os ânions e cátions maiores foram analisados e os resultados, empregados na caracterização e classificação das aguas por meio do diagrama de Piper. Verificou-se, considerando os parâmetros analisados, que todos os pontos de coleta apresentaram valores dentro dos limites estabelecidos pela Resolução CONAMA 396/08 e que os pontos de água subterrânea apresentaram características variadas entre mista, sódica e cálcica para cátions e dominantes bicarbonatadas para ânions, não variando em relação aos períodos de coleta.

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  • IPEN-DOC 24972

    SILVA, DIEGO S. da ; ALAYO, MARCOS I.; KASSAB, LUCIANA R.P.; ASSUMPCAO, THIAGO A.A. de; WETTER, NIKLAUS U. ; JIMENEZ-VILLAR, ERNESTO . Influence of silicon nanocrystals on the performance of Yb3+/Er3+: Bi2O3-GeO2 pedestal waveguides for amplification at 1542 nm. In: DUBOWSKI, JAN J. (Ed.); KABASHIN, ANDREI V. (Ed.); LINYOU, CAO (Ed.); GEOHEGAN, DAVID B. (Ed.) SYNTHESIS AND PHOTONICS OF NANOSCALE MATERIALS, 15th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 105210M-1 - 105210M-7. (SPIE Proceedings Series, 10521). DOI: 10.1117/12.2291326

    Abstract: This paper reports for, the first time, the influence of silicon nanocrystals on the photoluminescence and optical gain of Yb3+/Er3+ codoped Bi2O3–GeO2 waveguides for amplification at 1542 nm. Pedestal waveguides were fabricated by RF- sputtering followed by optical lithography and reactive ion etching. RF-sputtering followed by heat treatment produced silicon nanocrystals with average size of 8 nm and resulted in a photoluminescence enhancement of about 10 times for the 520 nm and 1530 nm emission bands. The resulting internal gain was 5.5 dB/cm at 1542 nm, which represents and enhancement of ~50%, demonstrating potential for applications in integrated optics.

    Palavras-Chave: waveguides; photoluminescence; nanocrystals; nanostructures; nanomaterials; optical properties; amplification; amplifiers; silicon; doped materials

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  • IPEN-DOC 24970

    SANTOS, LAISSA A.B. dos ; DAMATTO, SANDRA R. ; OLIVEIRA, JOSELENE de . Variação sazonal das concentrações de 226Ra, 228Ra e 210Pb das fontes de água mineral do Parque das Águas de Cambuquira e Marimbeiro, MG / Seasonal variation of 226Ra, 228Ra and 210Pb concentrations of the mineral waters from park of waters of Cambuquira and Marimbeiro, MG. In: CONGRESSO BRASILEIRO DE GEOQUIMICA, 16., 22-25 de agosto, 2017, Búzios, RJ. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Geoquímica, 2017.

    Abstract: Os elementos radioativos podem sem extraídos e arrastados pelas águas subterrâneas, porém quando se fala de águas minerais provindas de fontes subterrâneas uma característica marcante são as concentrações dos radionuclideos 226Ra e 222Rn originalmente dissolvidos. No entanto, outros radionuclídeos naturais como 228Ra e 210Pb, quando presentes, também contribuem para a irradiação interna do individuo. Assim determinou-se as concentrações de 226Ra, 228Ra e 210Pb em dez fontes minerais localizadas no Parque das Águas de Cambuquira e Marimbeiro. Os radionuclideos foram determinados por procedimento radioquimico em quatro coletas em diferentes estações do ano. As concentrações variaram de 4 ±1 mBq/L a 509 ± 32 mBq/L para 226Ra, de < 3,7 ± 0,1 mBq/L a 594 ±35 mBq/L para 228Ra e 5 ± 1 mBq/L a 59 ± 4 mBq/L para 210Pb.

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  • IPEN-DOC 24969

    SANTOS, DANIEL de P. dos; SARTORI, CARLOS A.F. . Impact of mismatch cables impedances on active motor terminal overvoltage mitigation using parallel voltage source inverters. In: GLOBAL ELECTROMAGNETIC COMPATIBILITY CONFERENCE, 3rd, November 08-10, 2017, São Paulo, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2017. p. 1-6.

    Abstract: Non-treated transient motor terminal overvoltage due high-speed switching sources and long cable length can be twice the original source voltage amplitude. In some cases, this overvoltage can cause premature motor insulation failure. A topology widely applied in industry is subject of this overvoltage: motors driven by voltage source inverter, connected by long feeding cable. There are several passive methods effective in mitigating overvoltage, but most of them are based in lossy and bulky passive component filters. A different approach is proposed by two low loss active methods for overvoltage mitigation with simple topologies. It consists in using voltage source inverters with specific switching strategy in order to attenuate the main cause of overvoltage: the superposition of traveling reflected pulses at the motor terminals. As promising methods for overvoltage mitigation, some specific studies regarding its particularities must be carried on in order to clear understand all its benefits and possible drawbacks. The present paper discusses the vulnerability of these overvoltage mitigation methods to some internal parameter variation. The impact of cables impedance variation due heating –and impedance mismatch– is highlighted, since it is intrinsic to the system and can degrades overvoltage mitigation.

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  • IPEN-DOC 24968

    RAELE, MARCUS P. ; SAMAD, RICARDO E. ; FREITAS, ANDERSON Z. ; PRETTO, LUCAS de ; AMARAL, MARCELLO M.; VIEIRA JUNIOR, NILSON D. ; WETTER, NIKLAUS U. . Backscattered light properties during femtosecond laser ablation and development of a dynamic interferometric focusing system. In: KAIERLE, STEFAN (Ed.); HEINEMANN, STEFAN W. (Ed.) HIGH-POWER LASER MATERIALS PROCESSING: APPLICATIONS, DIAGNOSTICS, AND SYSTEMS, 7th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 105250H-1 - 105250H-9. (SPIE Proceedings Series, 10525). DOI: 10.1117/12.2285899

    Abstract: The backscattered light originated when machining with femtosecond laser pulses can be used to accurately measure the processed surface position through an interferometer, as recently demonstrated by our group, in a setup that uses the same laser beam for ablation and inspection. The present work explores the characteristics of the laser light reflected by the target and its interaction with the resulting plasma to better understand its propagation physics and to improve the dynamic focusing system. The origin of this returning radiation was studied and has been traced, mainly, from the peripheral area of the focal spot (doughnut-like). By means of a Mach-Zehnder setup, the interferometric pattern was measured and analyzed aiming to access the influences of the plasma on the laser beam properties, and therefore on the retrieved information. Finally, the wavefront of the laser that creates and propagates through the plasma was characterized using a Shack-Hartmann sensor.

    Palavras-Chave: interferometry; lasers; ablation; plasma; backscattering; sensors; measuring instruments; laser beam machining; wavelengths

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  • IPEN-DOC 24967

    VASCONCELLOS, AGNALDO R. de; PIRES, MARIA A.F. . Protocolo de atuação para as instituições na minimização dos danos ambientais ocasionados pelos acidentes envolvendo Brownfields. In: CONGRESSO INTERNACIONAL DE MEIO AMBIENTE SUBTERRANEO, 5., 30-31 de outubro, 2017, São Paulo, SP. Proceedings... São Paulo: Associação Brasileira de Águas Subterrâneas, 2017.

    Abstract: A possibilidade de revitalização e reutilização de áreas contaminadas por substâncias perigosas surgiu como uma grande alternativa nos centros urbanos. A descontaminação desses sítios, também conhecidos como Brownfields, e sua reabilitação para reuso, além de se apresentar como opção à criação de espaços nos grandes centros, se destaca como solução na proteção à segurança pública, à saúde da população e ao meio ambiente (solos e águas subterrâneas) diante dos riscos oferecidos pelas substâncias ali presentes. Todavia, o tempo decorrido entre a identificação de um Brownfield e sua revitalização, existe a probabilidade da ocorrência de acidentes provocados pelo vazamento dos produtos perigosos ali depositados, ocasionando efeitos danosos à população e ao meio ambiente e consequentemente impondo ação imediata por parte do poder público. Com base em um estudo de caso o trabalho propõe a criação de um protocolo de atuação visando orientar os atores intervenientes nos cenários acidentais envolvendo Brownfields, na busca de reduzir ao mínimo ou até mesmo elidir os danos ambientais provocados por esse tipo de ocorrência.

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  • IPEN-DOC 24958

    OTTONI, CRISTIANE; SIMOES, MARTA F.; SOUZA, RODRIGO F.B. de; SANTOS, JONAS G.; NETO, ALMIR O. ; BRITO, ANTONIO G.; MAIORANO, ALFREDO E.. Synthetic vinasse treatment and bioenergy generation using microbial fuel cells techniche. In: SIMPOSIO NACIONAL DE BIOPROCESSOS, 21.; SIMPOSIO DE HIDROLISE ENZIMATICA DE BIOMASSA, 12., 3-6 de setembro, 2017, Aracaju, SE. Anais... 2017.

    Abstract: Brazil is one of the largest producers of ethanol in the world. However, during the process of ethanol production, large quantities of vinasse are generated which can be harmful to the biota due to its physical and chemical properties. Thus, there is a growing interest in identifying new processes for its treatment. Microbial fuel cells (MFC) are bioreactors whose technology has been considered promising for the treatment of biodegradable waste and simultaneous production of clean and sustainable energy. In this context, our study evaluated the possible application of a double chamber MFC for the vinasse treatment. We observed a reduction in chemical oxygen demand (COD) of 58.8%, and a current density of 330 mWm-2 in a period of 28 days. Taking into consideration our preliminary results, we concluded that the MFC technology presents itself as highly promising for the treatment of vinasse. However, further studies on the configuration and operation of the MFC are required for a higher number of cycles.

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  • IPEN-DOC 24957

    OLIVEIRA, EDUARDO S. ; SAMAD, RICARDO E. ; VIEIRA JUNIOR, NILSON D. ; ROSSI, WAGNER de . Selective ablation of titanium nitride film on tungsten carbide substrate using ultrashort laser pulses. In: LASERS IN MANUFACTURING CONFERENCE, June 26-29, 2017, Munich, Germany. Proceedings... Erlangen: German Scientific Laser Society, 2017. p. 1-8.

    Abstract: Many machining tools use coatings on their cutting surface to improve the machining process and increase its useful life. Due to damage or wear on the cutting edge, it is often desirable to remove this film for tool recovery. Doing this without damaging the base material is not easy due to the small thickness of the coating and because its hardness is much greater than that of the substrate. In this work, the removal of titanium aluminum nitride (TiAlN) coating on tungsten carbide (WC) was done with the use of femtosecond laser pulses. Complete film removal was obtained without damage to base material using a fluency far below that of the film ablation threshold for a single pulse. A decrease in this threshold was obtained by applying a high number of overlapping pulses with a low fluency until the incubation effects reduced the film damage threshold to a value slightly below to that of the substrate. With this technique precise and clean results were obtained and are reported in this work.

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  • IPEN-DOC 24956

    OLIVEIRA, ALINE S.G.R. de ; DAMATTO, SANDRA R. . Estudo da composição elementar de derivados brasileiros da Nicotiana tabacum L. pela análise por ativação com nêutrons instrumental / Study of the elemental composition of products derived from Nicotiana tabacum L. by Instrumental Neutron Activation Analysis. In: CONGRESSO BRASILEIRO DE GEOQUIMICA, 16., 22-25 de agosto, 2017, Búzios, RJ. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Geoquímica, 2017.

    Abstract: Neste trabalho foram determinados as concentrações dos elementos As, Ba, Br, Ca, Ce, Co, Cr, Fe, K, La, Na, Rb, Sc, Sm, Th e Zn presentes em produtos derivados de tabaco produzidos e comercializados no Brasil. Foram analisadas 48 amostras de cigarros não aromatizados, cigarros aromatizados, cigarros de palha e fumos de corda pela técnica analítica de Análise por Ativação com Nêutrons Instrumental (INAA). A partir dos resultados obtidos observou-se que as concentrações dos elementos Ba, Br, Ce, K, La, Sm e Zn são menores nos derivados processados, como os cigarros aromatizados, do que nos menos processados, como os fumos de corda. Observou-se também a presença de elementos tóxicos como As que apresentou concentrações superiores aos limites máximos de tolerância em alimentos. Entretanto a maioria dos elementos estudados apresentaram concentrações da mesma ordem de grandeza de estudos realizados em cigarros e plantas de tabaco da literatura.

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  • IPEN-DOC 24954

    MOREIRA, TATIANA M. ; SEO, EMILIA S.M. . Caracterização e utilização de fibras de coco como biossorvente na recuperação de corpos hídricos contaminados por derramamento de derivados do petróleo. In: CONGRESSO INTERNACIONAL DA REDE DE SANEAMENTO E ABASTECIMENTO DE AGUA, 3., 11-15 de setembro, 2017, Belo Horizonte, MG. Anais... São Paulo: Rede de Saneamento e Abastecimento de Água, 2017. p. 1-14.

    Abstract: Com base no desenvolvimento sustentável, este trabalho, visou buscar materiais tecnológicos com enfoque na reciclagem, onde se destacam as fibras vegetais, como as do coco, 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. As fibras do mesocarpo do Coco são lignocelulósicas obtidas a partir de frutos dos coqueiros (Cocos nucifera L.), os quais crescem abundantemente em países de clima tropical, como o Brasil. A preparação destas fibras foi feita por meio de tratamentos físicos e químicos, tais como: lavagem, secagem, secção, mercerização (tratamento químico com agente alcalino que ataca a superfície da fibra, melhorando suas características de sorção) 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.

    Palavras-Chave: bioadsorbents; vegetables; water resources; fibers

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  • IPEN-DOC 24953

    ALMEIDA, JORGE V. de; SIQUEIRA, GLAUCIO L.; MOSSO, MARBEY M.; SARTORI, CARLOS A.F. . Mu-negative metamaterials seen as band-limited non-Foster impedances for magnetic coupled systems. In: ZOUHDI, SAID (Ed.); RHO, JUNSUK (Ed.); LEE, HAKJOO (Ed.) INTERNATIONAL CONFERENCE ON METAMATERIALS, PHOTONIC CRYSTALS AND PLASMONICS, 8th, July 25-28, 2017, Incheon, Korea. Proceedings... 2017. p. 1-5.

    Abstract: In the last decade, various works have demonstrated that a class of artificial material called metamaterials (MTM) can synthesize μ-negative (MNG) media capable of evanescentwave focusing which largely enhances the magnetic coupling between coils, which is the basic mechanism of Inductive Power Transmission (IPT) systems. In the present work, MTM-enhanced coupling in IPT systems is examined through analytical and numerical results, which are validated by experimental data. Adopting a transmissionline based approach to describe the general MTM-enhanced IPT system, it is evidenced that MNG MTMs can be interpreted as a negative impedance from a circuital point of view.

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  • IPEN-DOC 24952

    LEE, S.Y.; VERST, C.G.; LANGTON, C.A.; MARUMO, J.T. ; VICENTE, R. ; FERREIRA, E.G. . Thermal modeling study for geologic borehole conceptual design. In: WASTE MANAGEMENT CONFERENCE, March 05-09, 2017, Phoenix, Arizona, USA. Proceedings... 2017. p. 1-16.

    Abstract: Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP) is developing a strategy for safe, permanent disposal of disused sealed radioactive sources (DSRS) from industrial and medical applications within Brazil. The Institute is proposing modifications to the International Atomic Energy Agency (IAEA) Borehole Disposal of Sealed Radioactive Sources (BOSS) concept originally developed by the Nuclear Energy Corporation of South Africa. The current Brazilian modified design differs from the IAEA design in that the disposal zone is below 300 m versus 30 m of the boss concept, and will be used to dispose of a much larger number of DSRS. These modifications result in a considerable departure from the generic safety case established by IAEA. Therefore, a new safety case is required to assess radiological and thermal impacts among other considerations. Predictive modeling and simulations were performed to address impacts of the proposed borehole concept at the early design stage in order to provide timely improvements to the concept and a traceable rationale for decisions made throughout the program as required by the safety case. Preliminary objectives of the modeling effort were focused on evaluating the mechanical and thermal loads anticipated within the current Brazilian borehole disposal concept in order to assess potential material and design issues. This paper presents the thermal modeling predictions and performance results for the proposed BOSS design.

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  • IPEN-DOC 24949

    JIMENEZ-VILLAR, E. ; MESTRE, VALDECI; WETTER, N.U. ; SA, GILBERTO F. de. Core-shell (TiO2@Silica) nanoparticles for random lasers. In: GALVEZ, ENRIQUE J. (Ed.); ANDREWS, DAVID L. (Ed.); GLUCKSTAD, JESPER (Ed.) COMPLEX LIGHT AND OPTICAL FORCES, 12th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 105490D-1 - 105490D-1. (SPIE Proceedings Series, 10549). DOI: 10.1117/12.2289228

    Abstract: Scattering media are of great current interest, due to their potential applications in photovoltaic cells, efficient photocatalyzers, random lasers and novel optical functional devices. Here, we have introduced a core–shell scattering medium for random lasing composed by core-shell nanoparticles (TiO2@Silica) suspended in an ethanol solution of Rhodamine 6G. Higher efficiency, lower laser threshold and long photobleaching lifetime were demonstrated in random laser. A promising method called fraction of absorbed pumping (FAP) has been introduced, which opens a new avenue to characterize and study scattering media. In this article, we also investigate the random laser action at the critical regime of localization by increasing considerably the concentration of TiO2@Silica nanoparticles. Narrow peaks arising in the random laser emission spectrum are observed. The classical superfluorescence band of the random laser was measured separately by collecting the emission at the back of the samples, showing a linear dependence with pumping fluence without gain depletion. However, frontal collection showed the saturation of emission and absorption. The emission spectrum of the peak mode (localized modes) shows approximately equal intensity, indicating suppression of the interaction between the peaks modes. The linewidth of these peaks is lower than that of the passive modes of the scattering medium, which was attributed to an anomalous nonlinear increase of the refractive index by localization.

    Palavras-Chave: nanoparticles; scattering; silica; titanium oxides; randomness; visible radiation; fluorescence; light transmission; wavelengths; wave functions

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  • IPEN-DOC 24948

    HARADA, JULIO ; AMORIM, CAMILA A. ; BRAGA, PAULA L. ; MACHADO, LUCI D.B. ; OLIVEIRA, RENE R. ; CABRAL NETO, ABNER; MACEDO, JOSE R.N.; SILVA, LEONARDO G.A. ; ROSA, DERVAL S.. Characterization of biodegradable mulch black films incorporated with organics fertilizers and rice husk ash. In: TMS ANNUAL MEETING AND EXHIBITION, 146th, February 26 - March 2, 2017, San Diego, CA, USA. Proceedings... 2017.

    Abstract: The effects of organic fertilizer, rice husk ash, both from renewable resources, were evaluated. Both of them were incorporated in biodegradable black mulch films. Morphological, mechanical and thermal properties based on PBAT/PLA composites with 2 % wt. of carbon black were investigated. In addition, the formulations were prepared with 1 % wt. to 2 % wt. rice husk ash and 2 % wt. to 4 % wt. % organic fertilizer The samples were produced by melt extrusion process, using a twin screw extruder machine and blown film extrusion process. As can be seen the properties of biodegradable mulch film samples were investigated by tensile tests, XRD, FTIR, TG, MEV analyses. Correlation between properties were discussed. According to the results it is possible to apply this composite as film for agricultural protection.

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  • IPEN-DOC 24947

    GIOVEDI, CLAUDIA; ABE, ALFREDO ; MUNIZ, RAFAEL O.R. ; GOMES, DANIEL S. ; SILVA, ANTONIO T. e ; MARTINS, MARCELO R.. Analysis of the combined effects on the fuel performance of UO2-BeO as fuel and iron-based alloy as cladding. In: WATER REACTOR FUEL PERFORMANCE MEETING, September 10-14, 2017, Jeju Island, Korea. Proceedings... 2017. p. 1-9.

    Abstract: Iron-based alloys have been considered as promising candidate material to replace zirconium-based alloys as fuel cladding based on the previous experience of the first generation of pressurized water reactors (PWR). Moreover, the safety margins of nuclear fuels can be improved by means of additives in the fuel pellet, as beryllium oxide (BeO), due to the increase of the fuel thermal conductivity. These efforts are part of the accident tolerant fuel (ATF) program which aims to develop nuclear fuel systems with enhanced performance under normal operation, design-basis accident and severe-accident conditions. This paper addresses the combined effects on the fuel performance considering the BeO additive in the fuel pellet and stainless steel 348 as cladding material under steady-state and loss-of-coolant-accident (LOCA) scenario. The fuel performance simulation and assessment are conducted using modified versions of well-known fuel performance codes (FRAPCON/FRAPTRAN). The obtained results have shown that the studied fuel system (stainless steel cladding and UO2-BeO) enables an improvement in the main parameters associated to the fuel safety margins under steady-state irradiation as well as LOCA scenario.

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  • IPEN-DOC 24945

    GUILHEN, S.N. ; PITOL-FILHO, L.; FUNGARO, D.A. . Kinetic study of uranium removal from aqueous solutions by macauba biochar. In: ENCONTRO BRASILEIRO SOBRE ADSORCAO, 12., 23-25 de abril, 2018, Gramado, RS. Anais... 2018.

    Abstract: Macauba (Acronomia aculeata) is a palm tree native of the Brazilian “cerrado” and a valuable renewable source of vegetable oil for human consumption and biodiesel production. Residue from the extraction of the coconut oil, the shell, or endocarp, can be used as a raw material for the production of biochar (BC) aiming the removal of uranium from aqueous solutions. Biochars are obtained by thermal decomposition of the biomass under inert atmosphere (pyrolysis) and, because of their surface properties and porous structure, they exhibit great potential as adsorbents. Adsorption of U(VI) was studied by a batch technique using a biochar produced through slow pyrolysis at 350°C of the macauba endocarp. The effect of contact time was investigated and a kinetic study was conducted to determine the mathematical model that best describes the adsorption process. The adsorption capacity (qmax) obtained for BC350 was 405 mg g-1.

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  • IPEN-DOC 24943

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

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

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  • IPEN-DOC 24942

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

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

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  • IPEN-DOC 24941

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

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

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  • IPEN-DOC 24940

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

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

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  • IPEN-DOC 24939

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

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

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

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  • IPEN-DOC 24929

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

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

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  • IPEN-DOC 24928

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

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

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  • IPEN-DOC 24935

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

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

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  • IPEN-DOC 24927

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

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

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  • IPEN-DOC 24924

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

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

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  • IPEN-DOC 24878

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

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

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

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  • IPEN-DOC 24877

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

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

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  • IPEN-DOC 24876

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

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

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  • IPEN-DOC 24875

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

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

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  • IPEN-DOC 24874

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

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

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  • IPEN-DOC 24873

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

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

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  • IPEN-DOC 24872

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

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

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  • IPEN-DOC 24871

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

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

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  • IPEN-DOC 24869

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

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

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  • IPEN-DOC 24821

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

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

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

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  • IPEN-DOC 24816

    FERREIRA, MERILYN S. ; PASK, HELEN M.; WETTER, NIKLAUS U. . Intracavity diode-side-pumped Raman laser at 1147 nm and 1163 nm. In: KUDRYASHOV, ALEXIS V. (Ed.); PAXTON, ALAN H. (Ed.); ILCHENKO, VLADIMIR S. (Ed.) LASER RESONATORS, MICRORESONATORS, AND BEAM CONTROL, 20th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 1051816-1 - 1051816-9. (SPIE Proceedings Series, 10518). DOI: 10.1117/12.2290596

    Abstract: Wavelengths in the yellow-orange range are of significant interest due to their application potential in the medical and biomedical areas, as well as for applications in laser displays and in remote sensing. These wavelengths can be obtained by frequency-doubling or sum-frequency generation of lasers with near-IR emission like VCSELS, fiber lasers, and OPOs. However, all these alternatives have several limitations that justify the development of alternative methods. As a possible solution for these limitations, a configuration of an intracavity converted Raman laser may be developed to obtain two wavelengths, 1163 nm, and 1147 nm, with high efficiency and good beam quality. This paper presents a configuration of a side-pumped intracavity converted Raman laser to achieve these objectives. A Nd:YLiF4 crystal was used as fundamental wavelength gain crystal. The side-pumped configuration guarantees practicability and cost reduction while allowing good efficiency and fundamental mode laser beam. The intracavity conversion configuration allows high fundamental wavelength power at the Stokes crystal in order to facilitate the obtention of the Stokes wavelengths and enables optimization of its efficiency. As a result an output power at 1163 nm of 3.8 W in the multimode regime was obtained, corresponding to a pump to Stokes efficiency of 9.6%. The TEM00 diode to Stokes efficiency was 7%. For the emission at 1147 nm, 1.5W of output power with a diode to Stokes efficiency of 3.7% was achieved. The side-pumped Nd:YLF/KGW intracavity Raman laser configuration is reported for the first time, to our knowledge.

    Palavras-Chave: scattering; raman effect; raman spectroscopy; diode-pumped solid state lasers; near infrared radiation; laser materials; crystals; wavelengths; absorption spectra

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  • IPEN-DOC 24814

    COSTA, PRISCILA ; RAELE, MARCUS P. ; SAMAD, RICARDO E. ; MACHADO, NOE G.P. ; VIEIRA JUNIOR, NILSON D. ; GENEZINI, FREDERICO A. . Femtosecond pulsed laser deposition of a boron thin film aiming at the development of a low-cost neutron detector. In: KAIERLE, STEFAN (Ed.); HEINEMANN, STEFAN W. (Ed.) HIGH-POWER LASER MATERIALS PROCESSING: APPLICATIONS, DIAGNOSTICS, AND SYSTEMS, 7th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 105250J-1 - 105250J-7. (SPIE Proceedings Series, 10525). DOI: 10.1117/12.2285896

    Abstract: Boron thin films were produced using femtosecond pulsed laser deposition aiming at the development of a neutron detector. As neutrons have no charge, in order to detect this particle converter materials are applied, promoting nuclear reactions that result in the emission of charged particles, allowing the neutrons presence to be indirectly inferred. Among the possible conversion materials, 10B has a considerable cross section for thermal neutrons and accessible cost. Furthermore, the nuclear reaction produces easily detectable alpha particles, making it a rational option to develop a low cost and portable neutron detector. The boron ablation threshold fluence has been measured by the Diagonal Scan (Dscan) technique that resulted in the minimum laser energy value of 17.7 (6) μJ and fluence of 5.63(19) J/cm2. Boron deposition was performed varying the pulse energy and deposition duration. The growth rate, morphological and physical aspects of the boron pulsed laser deposition were characterized by a Scanning Electron Microscope and an optical profilometer. The films surfaces have a flaky aspect with eventual droplets which had decayed overtime to a more smooth surface. The studied parameters allowed producing a boron coating with the optimal thickness in order to minimize self-absorption effect in the film, thus increasing efficiency.

    Palavras-Chave: laser radiation; neutron detectors; boron; thin films; lasers; ablation; scanning electron microscopy; thickness; deposition

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  • IPEN-DOC 24807

    WETTER, NIKLAUS U. ; BERECZKI, ALLAN ; PAES, JOAO P.F. . Quasi-three level Nd:YLF fundamental and Raman laser operating under 872-nm and 880-nm direct diode pumping. In: CLARKSON, W.A. (Ed.); SHORI, RAMESH K. (Ed.) SOLID STATE LASERS XXVII: TECHNOLOGY AND DEVICES, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 105111S-1 - 105111S7. (SPIE Proceedings Series, 10511). DOI: 10.1117/12.2290444

    Abstract: Nd:YLiF4 is the gain material of choice whenever outstanding beam quality or a birefringent gain material is necessary such as in certain applications for terahertz radiation or dual-frequency mode-locking. However, for high power CW applications the material is hampered by a low thermal fracture threshold. This problem can be mitigated by special 2D pump set-ups or by keeping the quantum defect to a minimum. Direct pumping into the upper laser level of Nd:YLiF4 is usually performed at 880 nm. For quasi-three level laser emission at 908 nm, direct pumping at this wavelength provides a high quantum defect of 0.97, which allows for very high CW pump powers. Although the direct pumping transition to the upper laser state at 872 nm has a slightly smaller quantum defect of 0.96, its pump absorption cross section along the c-axis is 50% higher than at 880 nm, leading to a higher absorption efficiency. In this work we explore, for the first time to our knowledge, 908 nm lasing under 872 nm diode pumping and compare the results with 880 nm pumping for quasicw and cw operation. By inserting a KGW crystal in the cavity, Raman lines at 990 nm and 972 nm were obtained for the first time from a directly pumped 908 nm Nd:YLF fundamental laser for both quasi-cw and cw conditions.

    Palavras-Chave: lasers; pumping; resonators; raman spectra; solid state lasers; diode-pumped solid state lasers; neodymium lasers; yttrium fluorides; lithium fluorides; crystals

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  • IPEN-DOC 24806

    WETTER, NIKLAUS U. ; BERECZKI, ALLAN ; FERREIRA, AMAURI A. . Dynamically stable operation of a 100-watt level CW single frequency ring laser at 1064 nm. In: KUDRYASHOV, ALEXIS V. (Ed.); PAXTON, ALAN H. (Ed.); ILCHENKO, VLADIMIR S. (Ed.) LASER RESONATORS, MICRORESONATORS, AND BEAM CONTROL, 20th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 1051811-1 - 1051811-7. (SPIE Proceedings Series, 10518). DOI: 10.1117/12.2290480

    Abstract: For high-resolution spectroscopy, a stable, narrow linewidth and high power output laser is desirable in order to pump different types of resonant optical parametric oscillators, which is the goal of the present work. Typical single frequency pump lasers are in the range of 10 watt output power whereas, depending on application and OPO type, higher power (>20 W) is desirable. Here we demonstrate a high-power single frequency laser based on off the shelf standard Nd:YAG pump modules. Two closely spaced, diode-side-pumped Nd:YAG rods were used in a mode-filling configuration to form a CW polarized ring resonator with TEM00 beam quality and output power of 105 W. The output power achieved is, to our knowledge, the highest reported for continuous polarized, fundamental-mode ring lasers using standard side-pumped Nd:YAG modules. The resonator allowed for power tuning over a large dynamic range and achieved excellent beam quality, using a half wave plate between both rods for birefringence compensation. Single frequency operation was achieved using a TGG crystal and an etalon, with a preliminary output power of 40 W.

    Palavras-Chave: spectroscopy; neodymium ions; neodymium lasers; laser pumping; solid state lasers; doped materials; resonators

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  • IPEN-DOC 24795

    SILVA, DIEGO S. da ; WETTER, NIKLAUS U. ; ROSSI, WAGNER de ; SAMAD, RICARDO E. ; KASSAB, LUCIANA R.P.. Femtosecond laser-written double line waveguides in germanate and tellurite glasses. In: NEUENSCHWANDER, BEAT (Ed.); GRIGOROPOULOS, COSTAS P. (Ed.); MAKIMURA, TETSUYA (Ed.); RACIUKAITIS, GEDIMINAS (Ed.) LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING (LAMOM), 23th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 105191B-1 - 105191B-9. (SPIE Proceedings Series, 10519). DOI: 10.1117/12.2291223

    Abstract: The authors report the fabrication and characterization of passive waveguides in GeO2–PbO and TeO2–ZnO glasses written with a femtosecond laser delivering pulses with 3μJ, 30μJ and 80fs at 4kHz repetition rate. Permanent refractive index change at the focus of the laser beam was obtained and waveguides were formed by two closely spaced laser written lines, where the light guiding occurs between them. The refractive index change at 632 nm is around 10-4 . The value of the propagation losses was around 2.0 dB/cm. The output mode profiles indicate multimodal guiding behavior. Raman measurements show structural modification of the glassy network. The results show that these materials are potential candidates for passive waveguides applications as low-loss optical components.

    Palavras-Chave: waveguides; lasers; laser radiation; germanates; tellurium oxides; glass; raman spectra; raman spectroscopy

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  • IPEN-DOC 24791

    SCURO, N.L. ; SANTOS, P.G. ; UMBEHAUN, P.E. ; ANDRADE, D.A. ; ANGELO, E.; ANGELO, G.. Transient cfd analysis of the flow inversion of the nuclear research reactor IEA-R1. In: EUROPEAN RESEARCH REACTOR CONFERENCE, March 11-15, 2018, Munich, Germany. Proceedings... Brussels, Belgium: European Nuclear Society, 2018.

    Abstract: The IEA-R1 research reactor works with a downflow direction, but after pumps shutdown during a LOFA test, the reactor shutdown. The heat decay will be removed by natural convection, which is an upward flow, originating flow inversion. Using the Instrumented Fuel Element designed at the Institute for Energy and Nuclear Research (IPEN), the loss of flow accident (LOFA) was analyzed along instrumented fuel plates. The preliminary results showed temperature peaks during inversion, which is as much representative as in nominal operation at 3.5MW. Therefore, these experimental data lead a construction and validation of a transient three-dimensional numerical analysis for a single fuel channel using the ANSYS-CFX® commercial code. The numerical results show improvement in obtaining more properties, e.g., wall heat transfer coefficient, which is usually obtained through empirical correlations.

    Palavras-Chave: research reactors; mathematical models; iear-1 reactor; numerical data; loss of flow; loss of coolant; reactor accidents; reactor safety; criticality; computer codes; computerized simulation; fluid mechanics

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  • IPEN-DOC 24779

    PRETTO, LUCAS R. de ; SAMAD, RICARDO E. ; ROSSI, WAGNER de ; FREITAS, ANDERSON Z. de . Optical coherence tomography characterization of femtosecond laser manufactured microfluidic circuits. In: GRAY, BONNIE L. (Ed.); BECKER, HOLGER (Ed.) MICROFLUIDICS, BIOMEMS, AND MEDICAL MICROSYSTEMS, 16th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 104911A-1 - 104911A-12. (SPIE Proceedings Series, 10491). DOI: 10.1117/12.2289937

    Abstract: Dimensional characterization of microfluidic circuits were performed using three-dimensional models constructed from OCT images of such circuits. Were fabricated microchannels on the same BK7 glass plate, under different laser ablation conditions and substrate displacement velocity in relation to laser beam. Were used the following combination of energy, from 30 μJ to 60 μJ and velocity from 588 mm/min to 1176 mm/min, at 1 kHz laser repetition rate and 40 fs of pulse duration (FWHM). For OCT imaging we used an OCP930SR (Thorlabs System Inc) with 930 nm central wavelength, 6 μm of lateral and axial resolution, and image of 500 x 512 pixel corresponding to 2.0 mm x 1.6 mm of lateral and axial scans respectively at 8 frames per second. We also characterized devices like, micropumps, microvalves and microreactors. It was possible register the micropumps and valves in action in real time. Using the OCT images analyses was possible to select the best combination of laser pulse energy and substrate velocity. All the devices were made in raster protocol, where laser beam pass through the same path in a controlled number of times, and with each iteration more material is removed and deeper the channels remain. We found a deformation at the edge of fabricated structures, due to velocity reduction of substrate in relation to laser beam, which causes more laser pulses superposition in these regions, and more material is ablated. The technique was thus evaluated as a potential tool to aid in the inspection of microchannels.

    Palavras-Chave: tomography; optical systems; optical modes; scanning electron microscopy; electron scanning; computer codes; fluidic control devices; lasers

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  • IPEN-DOC 24762

    MOSCA, RODRIGO C. ; YOUNG, NICHOLAS; ZEITUNI, CARLOS A. ; ARANY, PRAVEEN R.. [Ru(bipy)3]2+ nanoparticle-incorporate dental light cure resin to promote photobiomodulation therapy for enhanced vital pulp tissue repair. In: HAMBLIN, MICHAEL R. (Ed.); CARROLL, JAMES D. (Ed.); ARANY, PRAVEEN (Ed.) MECHANISMS OF PHOTOBIOMODULATION THERAPY, 13th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 104770T-1 - 104770T-6. (SPIE Proceedings Series, 10477). DOI: 10.1117/12.2290719

    Abstract: The use of nanoparticle on dental light cure resin is not new, currently several compounds (nanoadditives) are used to promote better communication between the restorative material and biological tissues. The interest for this application is growing up to enhance mechanical proprieties to dental tissue cells regeneration. Bioactive nanoparticles and complex compounds with multiple functions are the major target for optimizing the restorative materials. In this work, we incorporate [Ru(bipy)3]2+ nanoparticles, that absorbs energy at 450 nm (blue-light) and emits strongly at ~620 nm (red-light), in PLGA Microspheres and insert it in Dental Light Cure Resin to promote the Photobiomodulation Therapy (PBM) effects to accelerate dental pulp repair by in vitro using cytotoxicity and proliferation assay.

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  • IPEN-DOC 24731

    FILHO, J.C.S.; SOARES, E.P. ; VENANCIO, E.C.; SILVA, S.C.; TAKIISHI, T.. Influência do tratamento térmico na redução do óxido de grafeno. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo: Blucher, 2017.

    Abstract: A redução térmica de óxido de grafeno (GO) para o óxido de grafeno reduzido (rGO) é um passo importante no processamento para fabricar muitos materiais e dispositivos à base de grafeno. Neste trabalho, o GO foi sintetizado a partir do método de Hummers modificado, e as amostras foram tratadas termicamente à temperatura de 200°C, com uma rampa de aquecimento de 10°/min, e pressão de 10 kPa, durante o tempo de 15 e 30 minutos. A caracterização de GO pelo DRX exibiu apenas um pico em 10°, do conjunto de planos GO (002), e a TGA demonstrou que o GO possui 10% de moléculas de água, voláteis e 26,77% de grupos com oxigênio. As amostras de rGO indicaram a perda de massa em 100 e 200°C na TGA e uma menor intensidade na absorção em 3489 cm-1 na FTIR.

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  • IPEN-DOC 24725

    DIMMER, JESICA; SILVA, CAMILA R. ; MONTOYA, SUSANA C.N.; CABRERA, JOSE L.; RIBEIRO, MARTHA S. . Photodynamic activity of natural anthraquinones on fibroblasts. In: DAI, TIANHONG (Ed.) LIGHT-BASED DIAGNOSIS AND TREATMENT OF INFECTIOUS DISEASES, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 104790S-1 - 104790S-5. (SPIE Proceedings Series, 10479). DOI: 10.1117/12.2290666

    Abstract: Natural anthraquinones (AQs) isolated from Heterophyllaea lycioides (Rusby) Sandwith (Rubiaceae) demonstrated to have photodynamic properties: soranjididol (Sor), 5-Chlorosoranjidiol (5-ClSor), bisoranjidiol (Bisor), 7- Chlorobisoranjidiol (7-ClBisor) and lycionine (Lyc). Sor, 5-ClSor and Bisor exhibited photodynamic inactivation on bacteria and parasites. As they could be used in topical application, the aim of this work was to study their photodynamic activity on fibroblasts. AQs were tested at 2.5 μM in darkness and under irradiation conditions. They were photoactivated with violet-blue LED (λ = 410 ± 10 nm; fluence rate =50 mW/cm2) and exposure time corresponded to a fluence of 27 J/cm2. Negative and positive control (–C and +C, respectively) were included. Mitochondrial activity was determined by using MTT assay that is a measure of the cell viability and it was expressed as a percentage respect to –C (% CV). Results showed that AQs in darkness conditions showed similar metabolic activity as –C, except for 5-ClSor (about 75% CV). Under irradiation, AQs exhibited dissimilar results. Sor and 7-ClBisor maintained cell viability at approximately 100%, Bisor and Lyc around 70%, whereas 5-ClSor reduced cell viability by 90%. Taken together, our results suggest that Sor could mediate photodynamic therapy (PDT) in cutaneous infections since no toxicity was observed in fibroblasts. On the other hand, 5-ClSor could be used for topical PDT of keloids and hypertrophic scars.

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  • IPEN-DOC 24722

    CIONE, F.C. ; SOUZA, A.C.; SENE, F.F. ; GOMES, M.P. ; SOARES, E.P. ; ROSSI, J.L. . Obtention of WCuNi composite material using powder metallurgy for gamma (γ) radiation attenuation. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo: Blucher, 2017.

    Abstract: This work aimed to obtain a composite material WCuNi using the powder metallurgy. This composite is usable as material for the attenuation of gamma radiation (γ). The tungsten (W) is the main shielding element in this composite. The tungsten has high density (19.25 g.cm-3), high melting point (3,422 °C) and is presented as matrix of the composite. In order to meet the need for sintering with temperatures below 1,200 °C, the liquid phase sintering technique was used. For preparation of the samples, shape and size of the particles of the metal powders were analyzed. With the intention of homogenize the distribution of the metallic powders and to reduce the average particle size, a ball mill was used for 24 hours. After grinding, the particle size analysis showed that the mean particle size in WCuNi composition was 12 μm. The powder mixture was compacted in isostatic press at 200 MPa pressure. The samples were sintered at 1,100 °C and at 2,100 mbar pressure of reducing atmosphere (H2) for 8 hours. The formation of the isomorphic system CuNi is responsible for giving the mechanical characteristic of solid to the composite WCuNi. Optical and electronic microscopy (SEM) with EDS were undertaken to characterize the samples. The classical scientific method of experimentations with gamma radiation of the cobalt-60 source by attenuation of the energies was employed to study the effects on the samples. For the energies of 1,173 MeV and 1,332MeV the experimental method indicated the necessity of 11.95 mm of thickness for the solid compound W8Cu1Ni with the obtained density of 11.46 g.cm-3 to attenuate the energy to level allowed for occupationally exposed persons. The experimental values obtained were compared with values calculated by XCOM software database (NIST) of 12.45 mm and convergence of values was observed.

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  • IPEN-DOC 24703

    AMARAL, MARCELLO M.; RAELE, MARCUS P. ; ANA, PATRICIA A.; NUNEZ, SILVIA C.; ZAMATARO, CLAUDIA B. ; ZEZELL, DENISE M. . Wavelength comparison for laser induced breakdown spectroscopy caries detection. In: RECHMANN, PETER (Ed.); FRIED, DANIEL (Ed.) LASERS IN DENTISTRY, 24th, January 27 - February 01, 2018, San Francisco, California, USA. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2018. p. 104730K-1 - 104730K-6. (SPIE Proceedings Series, 10473). DOI: 10.1117/12.2288373

    Abstract: Laser Induced Breakdown Spectroscopy (LIBS) is a technique capable to perform elemental analyses of a variety of samples, independent of matter state. Other spectroscopy techniques may require a destructive and time-consuming sample preparation. On the other hand, LIBS is a less destructive technique with no (or considerably less) sample preparation, using a relatively simple experimental setup. LIBS also provides a multielement analysis into one single spectrum acquisition, applying a Nd:YAG short-pulsed laser to ensure the stoichiometry between the sample and the generated plasma. LIBS have been applied on the study of carious lesions using a Nd:YAG into its fundamental emission at 1064 nm. It was shown that ratio of P/Ca and Zn/Ca can be used to monitor the cariogenic process. Another minor elements, e.g. C and Cu, associated with bacteria biofilm were also measured with the Nd:YAG laser. The fundamental wavelength emission (1064 nm) of Nd:YAG is coincident with a hydroxyapatite transmission window and it may affect the result. In order to address this issue a study used the second harmonic of the Nd:YAG laser at 532 nm. It was show that it is also possible perform LIBS on carious lesion using the Nd:YAG at 532 nm. However, there is not a work direct comparing the LIBS at 532 nm and 1064 nm for carious lesion detection. So, the aim of this work was to investigate the influence of laser wavelength on the LIBS performance for carious lesion detection. In both cases the carious lesion was detected with the advantage of no interference with hydroxyapatite at 532 nm.

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  • IPEN-DOC 24695

    PENHALBEL, LUCIANO T.B.; PILLIS, MARINA F. . Tribological evaluation of intake valve and valve seat of a diesel cycle engine in real operating conditions. In: SIMPOSIO INTERNACIONAL DE ENGENHARIA AUTOMOTIVA, 25., 12-13 de setembro, 2017, São Paulo, SP. Proceedings... São Paulo: Blucher, 2017. DOI: 10.5151/engpro-simea2017-01

    Abstract: Automotive industry demands products that work under extreme conditions. The development of components for internal combustion engines is an action to improve this product, so that it reaches the required life with acceptable levels of wear and respecting the legal operating limits, such as values of emission pollutants. In view of these requirements, it is necessary to study components considered critical, which are known to influence the performance of the engine. So, within this universe the tribology of the intake valve and valve seat insert is an important set, that must receive attention to its wear and consequently its influence on the engine degradation, in the emission of pollutants and performance related to the operational maintenance requirements and life of the product. The aim of this work is to evaluate the behavior of the tribological intake pair, valve and valve seat insert, submitted to dynamometer and vehicular tests (real operating conditions), regarding the level and type of wear occurred in the pair. Correlating the results obtained with legal and operational performance requirements of a Diesel cycle engine, as well as the characterization of the wear type occurred in the tribological pair, with the related literature.

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  • IPEN-DOC 24691

    LANDULFO, EDUARDO ; SILVA, JONATAN J. da ; LOPES, FABIO J.S. . Cloud-Aerosols interactions by multiple scenarios approach. In: COMERON, ADOLFO (Ed.); KASSIANOV, EVGUENI I. (Ed.); SCHÄFER, KLAUS (Ed.); PICARD, RICHARD H. (Ed.); WEBER, KONRADIN (Ed.) REMOTE SENSING OF CLOUDS AND THE ATMOSPHERE, 22th, September 11-14, 2017, Warsaw, Poland. Proceedings... Bellingham, WA, USA: Society of Photo-optical Instrumentation Engineers, 2017. p. 104240Z-1 - 104240Z-10. (SPIE Proceedings Series, 10424). DOI: 10.1117/12.2278588

    Abstract: Aerosols can play the role of cloud and ice condensation nuclei. This study shows a set of measurements and experiments analysis in remote sensing, in distinct scenarios of cloud cover during day/nightime measurements using lidar, visible all-sky camera and solar photometry. The retrieved products are studied to obtain aerosol optical and physical properties in the vicinity of clouds. In this approach cloud cover and optical properties should be retrieved as well as main features used for cloud pixel identi cation, e. g., Red-Blue Di erence, Red- Blue Ratio, Normalized Red-Blue Ratio, Saturation and Intensity. We show some case studies to illustrate this methodology.

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  • IPEN-DOC 24689

    GONNELLI, EDUARDO ; PINTO, LETICIA N. ; DINIZ, RICARDO ; SANTOS, ADIMIR dos . Characterization of neutron detectors at the IPEN/MB-01 nuclear reactor. In: INTERNATIONAL SEMINAR ON SENSOR, INSTRUMENTATION, MEASUREMENT AND METROLOGY, August 25-26, 2017, Surabaya, Indonesia. Proceedings... Piscataway, NJ: IEEE, 2017. p. 99-103. DOI: 10.1109/issimm.2017.8124271

    Abstract: A huge Brazilian nuclear project, the Brazilian Multipurpose Research Reactor (RMB), is being carried out and one of the project steps is to verify experimentally the physical quantities related to the operational performance of the new fuel elements. In this context, the aim of this work is to characterize the neutron detectors due to its crucial role during the nuclear reactor criticalization. A series of experiments was performed at the IPEN/MB-01 nuclear reactor in order to characterize a set of new helium-3-filled gas proportional counters. The detectors characterization procedure takes into account the operating voltage curve and the detectors dead time. The Rossi-α method was employed in order to acquire the time difference between a detected neutron pair. The dead time determination through the Rossi-α method is very important to discriminate the reflector effect over the neutron lifetimes in subcritical reactivity levels. Furthermore, the Auto Power Spectral Densities (APSD) for those new detectors were experimentally acquired and those results were compared among some well-known detectors and with theoretical simulation results using the MCNP5 code with the ENDF/B-VII.0 library neutron data.

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  • IPEN-DOC 24669

    MERGULHAO, MARCELLO V. ; PODESTA, CARLOS E. ; NEVES, MAURICIO D.M. das . Investigation of mechanical, microstructural and thermal behavior of CoCrMo alloy manufactured by selective laser melting and casting techniques. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICACAO, 9., 26-29 de junho, 2017, Joinville, SC. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2017.

    Abstract: A route of increasing development in additive manufacturing (3D printing) process using metal alloys is the selective laser melting (SLM). 3D building components is possible by laser power that completely melts the metal powder particles. SLM was applied in a biomaterial of CoCrMo alloy, to study the mechanical properties and microstructural characterization in comparison of the conventional technique – lost wax casting. The gas atomized powder was investigated by their physical (as apparent density, bulk density and flow rate) and chemical properties (X-ray fluorescence). Standard samples evaluated the mechanical properties as yield strength, elongation, elastic modulus, transverse rupture strength and the Vickers hardness. Microstructural characterization was performed using optical microscope (OM) and scanning electron microscope (SEM-EDS). Thermal analysis of CoCrMo alloy were investigated using thermomechanical analysis (TMA) and differential scanning calorimetry (DSC) techniques. The results of mechanical properties showed higher values in the SLM specimens compared with the obtained in the cast specimens. The micrographs revealed a typical morphology of consolidation process, characterized by selected layer used in the SLM technique and the dendrites arms in the casting technique. The thermal results confirm the phase’s transitions of CoCrMo alloy.

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  • IPEN-DOC 24630

    SA, ANA P.N. de ; VILLAVICENCIO, ANNA L.C.H. . Avaliação dos efeitos das radiações ionizantes em farinhas – artigo de revisão. In: ANAIS DA SOCIEDADE BRASILEIRA DE BIOCIENCIAS NUCLEARES, 09-11 de outubro, 2017, São Paulo, SP. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Biociências Nucleares, 2017. p. 74-81.

    Abstract: A radiação é uma alternativa eficiente, de grande valor tecnológico no emprego de doses até 10 kGy para alimentos secos, desidratados e com baixo teor de gorduras. O objetivo desta pesquisa é realizar através de levantamento bibliográfico sobre os trabalhos existentes com finalidade tecnológica em farinhas e disponíveis na literatura para médias e altas doses de radiação. O estudo foi baseado nos dados de bases brasileiras e internacionais, tais como: “Google Scholar”, “ScienceDirect”, “Pubmed”, “SciELO”, "Web of Science". Foram coletados resultados do período compreendido entre os anos de 1980 e 2017, em farinhas provenientes de milho, mandioca, trigo, feijão, arroz, castanha, fubá e banana. Foram utilizadas palavras-chave tanto em Português como em Inglês: irradiação de alimentos; farinhas irradiadas e aspectos tecnológicos de farinhas irradiadas; food irradiation, technology aspects of irradiated flour. Os resultados da pesquisa/busca mostram que as doses variam desde a aplicação para fitossanitário até doses mais altas relacionadas às características tecnológicas. Foram encontrados 10 trabalhos com finalidade fitossanitária (0,1 a 1,0 kGy) e 20 com as características tecnológicas (doses acima de 1 kGy até 10 kGy). Nos trabalhos foram observados estudos relacionados com redução de carga microbiológica, composição nutricional, modificações organolépticas e relação do aumento do índice de acidez presente em fubá/castanha e também uma tendência de melhora como meio de aperfeiçoamento na produção de panificação em alguns artigos. Desta forma, com base na literatura avaliada, Concluímos que as tecnologias de irradiação de alimentos com doses médias apresentam vantagens e melhoram as características na produção de pães.

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  • IPEN-DOC 24629

    BELINATO, WALMIR; SANTOS, WILLIAM S.; PERINI, ANA P.; NEVES, LUCIO P.; CALDAS, LINDA V.E. ; SOUZA, DIVANIZA N.. Avaliação de doses equivalentes em PET/CT com 18F utilizando o Método Monte Carlo com código MCNPX. In: ANAIS DA SOCIEDADE BRASILEIRA DE BIOCIENCIAS NUCLEARES, 09-11 de outubro, 2017, São Paulo, SP. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Biociências Nucleares, 2017. p. 60-73.

    Abstract: A técnica diagnóstica PET/CT (Positron Emisson Tomography/Computer Tomography) une recursos diagnósticos da Medicina Nuclear e da Radiologia. A técnica PET produz imagens metabólicas por meio de radiofármacos emissores de pósitrons. O presente trabalho usou o método Monte Carlo (MMC), especificamente o código de Monte Carlo NParticle – MCNPX, para simular a interação da radiação envolvendo fótons e partículas, tais como pósitrons e elétrons, com simuladores antropomórficos adultos virtuais em exames de PET/CT e determinar doses absorvidas e equivalentes em exames de pacientes adultos masculino e feminino. Para os cálculos, considerou-se os parâmetros dos feixes de tomografia computadorizada (colimação e filtração) de dois equipamentos distintos e as atividades de 18F-FDG comumente empregadas em exames de rotina. Foram estimados novos valores para fatores de conversão de dose absorvida por atividade administrada (valores-S) para doses internas em órgãos de pacientes com características similares aos simuladores de voxels escolhidos. Comparando-se com as doses absorvidas em órgãos devido ao 18F (doses internas), as doses absorvidas médias externas - devido ao feixe de raios X de CT - equivalem a 14,2% (equipamento GE) e 26,3% (equipamento Siemens). Essa diferença entre equipamentos pode ser relacionada principalmente com a quantidade de cortes de CT necessários para o exame de corpo inteiro (40 mm/rotação para ao GE e 20 mm/rotação para o Siemens), com uso do filtro gravata borboleta (filtro bowtie). Considerando-se as doses absorvidas internas, os novos coeficientes por atividade administrada calculados apresentaram um acréscimo próximo de 30% em relação aos valores da ICRP 106 e podem ser associados com representação morfológica mais realista dos órgãos dos simuladores utilizados e à introdução de fatores de espalhamento para fótons, porque os simuladores foram dispostos sobre uma mesa de exames, o que não é levado em consideração na ICRP 106.

    Palavras-Chave: absorbed radiation doses; dosimetry; equivalent radiation doses; fluorine 18; fluorodeoxyglucose; icrp; monte carlo method; phantoms; positron computed tomography; simulators

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  • IPEN-DOC 24492

    PEREIRA, MARIA da C.C. ; MADI FILHO, TUFIC ; BERRETTA, JOSE R. ; CARDENAS, JOSE P.N. ; RODRIGUES, ANTONIO C.I. . Response of CsI:Pb scintillator crystal to neutron radiation. In: LYOUSSI, A. (Ed.); CARETTE, M. (Ed.); GIOT, M. (Ed.); LE DU, P. (Ed.); REYNARD-CARETTE, C. (Ed.); SCHYNS, M. (Ed.); VERMEEREN, L. (Ed.) ADVANCEMENTS IN NUCLEAR INSTRUMENTATION MEASUREMENT METHODS AND THEIR APPLICATIONS, June 19-23, 2017, Liège, Belgium. Proceedings... Les Ulis, France: EDP Sciences, 2018. p. 1-4. (EPJ Web of Conferences, 170). DOI: 10.1051/epjconf/201817001005

    Abstract: The helium-3 world crisis requires a development of new methods of neutron detection to replace commonly used 3He proportional counters. In the past decades, great effort was made to developed efficient and fast scintillators to detect radiation. The inorganic scintillator may be an alternative. Inorganic scintillators with much higher density should be selected for optimal neutron detection efficiency taking into consideration the relevant reactions leading to light emission. These detectors should, then, be carefully characterized both experimentally and by means of advanced simulation code. Ideally, the detector should have the capability to separate neutron and gamma induced events either by amplitude or through pulse shape differences. As neutron sources also generate gamma radiation, which can interfere with the measurement, it is necessary that the detector be able to discriminate the presence of such radiation. Considerable progress has been achieved to develop new inorganic scintillators, in particular increasing the light output and decreasing the decay time by optimized doping. Crystals may be found to suit neutron detection. In this report, we will present the results of the study of lead doped cesium iodide crystals (CsI:Pb) grown in our laboratory, using the vertical Bridgman technique. The concentration of the lead doping element (Pb) was studied in the range 5x10-4 M to 10-2 M . The crystals grown were subjected to annealing (heat treatment). In this procedure, vacuum of 10-6 mbar and continuous temperature of 350°C, for 24 hours, were employed. In response to neutron radiation, an AmBe source with energy range of 1 MeV to 12 MeV was used. The activity of the AmBe source was 1Ci Am. The fluency was 2.6 x 106 neutrons/second. The operating voltage of the photomultiplier tube was 1700 V; the accumulation time in the counting process was 600 s and 1800 s. The scintillator crystals used were cut with dimensions of 20 mm diameter and 10 mm height.

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  • IPEN-DOC 24495

    ZAFALON, ANGELICA T. ; SANTOS, VINICIUS J.; LINCOPAN, NILTON; ESPOSITO, FERNANDA; LUGAO, ADEMAR B. ; PARRA, DUCLERC F. . Preparação e caracterização de hidrogel para liberação controlada de neomicina. In: CONGRESSO DA SOCIEDADE LATINO AMERICANA DE BIOMATERIAIS, ORGAOS ARTIFICIAIS E ENGENHARIA DE TECIDOS, 14.; EDICAO DO WORKSHOP DE BIOMATERIAIS, ENGENHARIA DE TECIDOS E ORGAOS ARTIFICIAIS, 5., 20-24 de agosto, 2017, Maresias, SP. Anais... 2017. p. 825-830.

    Abstract: Os hidrogéis têm sido empregados na medicina como biosensores, na engenharia de tecidos e como sistema de liberação de fármacos por serem biocompatíveis e atóxicos. Estudos recentes demonstram o uso de hidrogéis como curativos para a liberação controlada de antiinflamatórios, fatores de crescimentos e antibióticos para o tratamento tópico de infecções. Com o aumento de casos de bactérias super-resistentes, principalmente Staphylococcus aureus Meticilina Resistente (MRSA), o higrogel tornou-se uma ferramenta importante para superar esse problema, pois esses fármacos são liberados diretamente na região comprometida aumentando a efetividade do tratamento. Além disso, fornecem um ambiente úmido evitando a adesão ao local da ferida e apresentam boa barreira contra microrganismos. A presença do fármaco não alterou a fração gel. O intumescimento foi realizado com a imersão da membrana em água à temperatura ambiente e pesagem até peso constante. O intumescimento máximo foi atingido após 24 horas de imersão O intumescimento foi realizado com imersão da membrana em água. A liberação “in vitro” da neomicina foi avaliada empregando a técnica de cromatografia líquida de alta eficiência acoplada a espectrometria de massas (HPLC-MS/MS). Observou-se que o aumento da dose de irradiação influenciou na absorção de água e na fração gel devido ao aumento da densidade de ligações cruzadas. A presença do fármaco não alterou a fração gel. O intumescimento em solução salina foi 4% maor que o obtido em água. A liberação do fármaco foi avaliada “in vitro” empregando-se a técnica de cromatografia líquida de alta eficiência acoplada à espectrometria de massas (HPLC-MS/MS). O pico máximo de liberação foi alcançado após 8 horas e permaneceu constante até 48h. O teste microbiológico demonstrou que o hidrogel foi capaz de inibir o crescimento microbiológico.

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  • IPEN-DOC 24459

    TEIXEIRA, MARIA I. ; CALDAS, LINDA V.E. . Optical stimulated luminescence from Citrine for high-doses dosimetry. In: CONGRESSO BRASILEIRO DE METROLOGIA, 9.; CONGRESSO INTERNACIONAL DE METROLOGIA MECANICA, 4.; CONGRESSO INTERNACIONAL DE METROLOGIA ELETRICA, 12.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇOES IONIZANTES, 4.; WORKSHOP DA REDE DE METROLOGIA QUIMICA DO INMETRO, 3.; CONGRESSO BRASILEIRO DE METROLOGIA OPTICA, 2., 26-29 de novembro, 2017, Fortaleza, CE. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2017. p. 1-4.

    Abstract: Several Brazilian stone samples were already studied at IPEN for use in radiation dosimetry, using the techniques of thermoluminescence, optical absorption and optically stimulated luminescence. The possibility of using semi-precious stones from Brazilian have been studied and tested, using the technique of thermoluminescence. The objective of this work was to study citrine samples for application in high-dose dosimetry, using the OSL technique. The samples exposed to gamma irradiated (60Co) with doses up to 300 kGy. The reproducibility of the response and the OSL lower detection limit were obtained. The results show is a material that can be useful for high-dose dosimetry

    Palavras-Chave: cobalt 60; dose-response relationships; dosimetry; elements; gamma radiation; luminescent dosemeters; neutron activation analysis; radiation doses; silica; thermoluminescence

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  • IPEN-DOC 24451

    CALDAS, LINDA V.E. ; COSTA, JHONATHA J.L.; NASCIMENTO, ERIBERTO O. do; OLIVEIRA, LUCAS N. de . Pressure sound level measurements at an educational environment in Goiania, Goias, Brazil. In: CONGRESSO BRASILEIRO DE METROLOGIA, 9.; CONGRESSO INTERNACIONAL DE METROLOGIA MECANICA, 4.; CONGRESSO INTERNACIONAL DE METROLOGIA ELETRICA, 12.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇOES IONIZANTES, 4.; WORKSHOP DA REDE DE METROLOGIA QUIMICA DO INMETRO, 3.; CONGRESSO BRASILEIRO DE METROLOGIA OPTICA, 2., 26-29 de novembro, 2017, Fortaleza, CE. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2017. p. 1-4.

    Palavras-Chave: acoustic monitoring; educational facilities; environmental impacts; noise pollution; performance; sound waves

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  • IPEN-DOC 24450

    ULRICH, JOAO C. ; GUILHEN, SABINE N. ; COTRIM, MARYCEL E.B. ; PIRES, MARIA A.F. . Method development and validation for simultaneous determination of IEAR1 reactor's pool water U and Si content by ICP OES. In: CONGRESSO BRASILEIRO DE METROLOGIA, 9.; CONGRESSO INTERNACIONAL DE METROLOGIA MECANICA, 4.; CONGRESSO INTERNACIONAL DE METROLOGIA ELETRICA, 12.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇOES IONIZANTES, 4.; WORKSHOP DA REDE DE METROLOGIA QUIMICA DO INMETRO, 3.; CONGRESSO BRASILEIRO DE METROLOGIA OPTICA, 2., 26-29 de novembro, 2017, Fortaleza, CE. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2017. p. 1-5.

    Palavras-Chave: validation; pool type reactors; uranium; silicon; emission spectroscopy; optical systems; plasma

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  • IPEN-DOC 24449

    MARQUES, JOYCE R. ; FAUSTINO, MAINARA G. ; MONTEIRO, LUCILENA R. ; ULRICH, JOAO C. ; PIRES, MARIA A.F. ; COTRIM, MARYCEL E.B. . Is my bottom-up uncertainty estimulation on metal measurement adequate?. In: CONGRESSO BRASILEIRO DE METROLOGIA, 9.; CONGRESSO INTERNACIONAL DE METROLOGIA MECANICA, 4.; CONGRESSO INTERNACIONAL DE METROLOGIA ELETRICA, 12.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇOES IONIZANTES, 4.; WORKSHOP DA REDE DE METROLOGIA QUIMICA DO INMETRO, 3.; CONGRESSO BRASILEIRO DE METROLOGIA OPTICA, 2., 26-29 de novembro, 2017, Fortaleza, CE. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2017. p. 1-4.

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  • IPEN-DOC 24251

    SILVA, D.B. ; SILVA, T.B.S.C. ; MONTEIRO, L.R. ; FAUSTINO, M.G. ; MARQUES, J.R. ; STELLATO, T.B. ; SOARES, S.M.V. ; PIRES, M.A.F. ; COTRIM, M.E.B. . Guarapiranga dam (São Paulo-SP/Brazil) nitrogen distribution. In: IWA EASTERN EUROPEAN CONFERENCE FOR YOUNG WATER PROFESSIONALS, 9th, May 24-27, 2017, Budapest, Hungary. Proceedings... 2017.

    Abstract: Nowadays Guarapiranga Dam is responsible for about 20% of Metropolitan Region of São Paulo (RMSP) water supply. However, since the 60s an irregular and disordered occupation appears in the area. From the 70’s, the reservoir was reported eutrophic due to untreated urban sewage. Cyanobacteria blooms were frequent since 1990. Nitrogen species are a significant part of this eutrophication problem. In this scenario, the present work presents the distributions of nitrogen species in the Guarapiranga Dam, to compare with other lakes and reservoirs status in the world and to find options to this nutrient management in Guarapiranga Reservoir.

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  • IPEN-DOC 24249

    SILVEIRA, LUCAS M. da; PEREIRA, MARCO A.M.; NEVES, LUCIO P. ; PERINI, ANA P.; BELINATO, WALMIR; CALDAS, LINDA V.E. ; SANTOS, WILLIAM S.. Exposition to 137Cs deposited in soil – a Monte Carlo study. In: CONGRESSO BRASILEIRO DE METROLOGIA, 9.; CONGRESSO INTERNACIONAL DE METROLOGIA MECANICA, 4.; CONGRESSO INTERNACIONAL DE METROLOGIA ELETRICA, 12.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇOES IONIZANTES, 4.; WORKSHOP DA REDE DE METROLOGIA QUIMICA DO INMETRO, 3.; CONGRESSO BRASILEIRO DE METROLOGIA OPTICA, 2., 26-29 de novembro, 2017, Fortaleza, CE. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2017. p. 1-4.

    Abstract: In the event of environmental contamination with radioactive materials, one of the most dangerous materials is 137Cs. In order to evaluate the radiation doses involved in an environmental contamination of soil, with 137Cs, we carried out a computational dosimetric study. We determined the radiation doses conversion coefficients (CC) for E and HT, using a male and a female anthropomorphic phantom, coupled with the MCNPX (2.7.1) Monte Carlo simulation software, for three different types of soil. The highest CC[HT] values were for the gonads and skin (male) and bone marrow and skin (female). We found no difference for the different types of soil.

    Palavras-Chave: cesium 137; radiation accidents; environmental exposure; contamination; soils; monte carlo method; radiation sources; computer codes; dosimetry; radiation monitoring; radiation protection

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  • IPEN-DOC 24248

    KIBRIT, EDUARDO ; MACHADO, ROGERIO J.; KRUGLIANSKAS, ISAK. Gestão da inovação sustentável – estudo de caso único em uma startup. In: ENCONTRO INTERNACIONAL SOBRE GESTAO EMPRESARIAL E MEIO AMBIENTE, 19., 04-05 de dezembro, 2017, São Paulo, SP. Anais... 2017. p. 1-17.

    Abstract: Uma empresa inovadora pode ser considerada sustentável quando introduz novidades que atendam às múltiplas dimensões da sustentabilidade em bases sistemáticas. Para ser sustentável, não basta apenas inovar constantemente, mas inovar considerando as três dimensões da sustentabilidade, econômica, ambiental e social. Neste artigo, por meio de estudo de caso único, mostramos como uma startup obtém sucesso com seu modelo de negócio, por meio de práticas de gestão da inovação. Realizamos uma pesquisa bibliográfica sobre embalagens sustentáveis usadas na indústria automobilística; o estudo de caso único; os conceitos de recycling, downcycling e upcycling; e o modelo de valor sustentável. Realizamos uma entrevista com o diretor geral de uma startup do ramo de embalagens industriais sustentáveis e coletamos dados sobre o sistema de gestão dessa empresa. Por meio de um modelo teórico de valor sustentável, avaliamos o sistema de gestão da startup quanto à sustentabilidade e apontamos as práticas coerentes e as lacunas do sistema de gestão em relação ao modelo teórico. Mostramos que a empresa em estudo possui proposta de valor de mercado melhor que de suas concorrentes e com o foco em inovação, a empresa demonstra sucesso em seu modelo de negócio.

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  • IPEN-DOC 24260

    VICENTE, R. ; TOLEDO, R.N.; REZENDE, R.; DELLAMANO, J.C. ; MARUMO, J.T. . Development of microwave technology for TENORM waste treatment - 17377. In: WASTE MANAGEMENT CONFERENCE, March 05-09, 2017, Phoenix, Arizona, USA. Proceedings... 2017. p. 1-6.

    Abstract: The sludge and scales generated by the oil and gas industry usually contain radionuclides of the thorium and uranium decay chains, the so-called technologically enhanced, naturally occurring radioactive materials (TENORM) waste. The handling of this waste must consider both the radiation risks presented by those radionuclides and its chemical toxicity, due to the decomposition of oil residues, which may generate hydrogen sulfide and other hazardous compounds. In the case of Brazil, Public Law 10.308 limits the management options for radioactive waste generated by offshore oil production rigs to drumming and storage; it prohibits disposal of any radioactive waste in seawaters, seabed or oceanic islands. This paper describes the results of the work to develop a treatment process using a specially designed microwave oven, which removes simultaneously water and hydrocarbons from the sludge, thus reducing the volume, the chemical toxicity and the chemical reactivity of the waste.

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  • IPEN-DOC 24259

    SMITH, RICARDO B. ; VICENTE, ROBERTO . Project basis for automation of a quality assurance system in radioactive waste management - 17317. In: WASTE MANAGEMENT CONFERENCE, March 05-09, 2017, Phoenix, Arizona, USA. Proceedings... 2017. p. 1-9.

    Abstract: A low- and intermediate-level radioactive waste management facility is required to comply with Regulation 1.16 of the Brazilian National Nuclear Energy Commission "Quality Assurance for the Safety of Nuclear Power Plants and Other Facilities". However, the text of this regulation is very generic and does not address the more specific controls necessary for the management of quality. Therefore, the objective of this paper is to identify such detailed controls in all applicable activities of the facility and to provide an implementation plan in the form of flowcharts, for further development of an automated system. This work takes as a basis the recommendations of the International Atomic Energy Agency and the rules and procedures implemented by the U.S. Department of Energy’s Office of Civilian Waste Management related to Quality Assurance. In such way, we intend to provide a more reliable implementation system of quality assurance for the management of radioactive waste in Brazil.

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  • IPEN-DOC 24258

    CABRERA, PALOMA S. ; VICENTE, ROBERTO ; FERREIRA, EDUARDO ; MARUMO, JULIO T. . Proposal of a categorization of the disused sealed radioactive sources with a view to safe – 17285. In: WASTE MANAGEMENT CONFERENCE, March 05-09, 2017, Phoenix, Arizona, USA. Proceedings... 2017. p. 1-8.

    Abstract: In the Nuclear and Energy Research Institute (IPEN-CNEN/Brazil) many works to improve and develop characterization of radioactive waste techniques have been deployed by the Radioactive Waste Management Department (IPEN-CNEN/SP). In this line, this work aims to suggest a new categorization of sealed sources, which considers their activities, as suggested by the International Atomic Energy Agency (IAEA), but also the time required for the activity to decrease to a safe value. We considered the sealed sources categorization system suggested by the IAEA and we applied such categorization system to various sources currently stored by institutes of Brazilian Nuclear and Energy Commission (CNEN). Then, we also applied the categorization system defined herein, it follows that the categorization system presented by the IAEA has many applications and their use should not be abandoned. However, since the new proposed categorization systems allow to differentiate sources that in the IAEA system are in the same category, they can help define the long-term management of radioactive waste.

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  • IPEN-DOC 24257

    FERREIRA, EDUARDO ; MARUMO, JULIO T. ; FERREIRA, RAFAEL V. de P.. Immobilization in cement of rice husk used as biosorbent of radionuclides present in radioactive liquid waste – 17225. In: WASTE MANAGEMENT CONFERENCE, March 05-09, 2017, Phoenix, Arizona, USA. Proceedings... 2017. p. 1-8.

    Abstract: The use of new techniques for the treatment of radioactive liquid wastes has been studied in the last few years by many countries. In this context, the biosorption has been an attractive process. In Brazil the Radioactive Waste Management Laboratory of Nuclear and Energy Research Institute (IPEN-CNEN/SP), studied some biomasses to be used as biosorbents to remove radionuclides of the radioactive liquid waste stored in this institute. The rice husk is a low cost and wide available byproduct of the agriculture and its biosorption capacity has been proved as feasible. Thus, it is necessary to evaluate if its immobilization in a cementitious matrix will result in a waste form that meets the requirements of Brazilian regulations for final disposal of low and intermediate level waste. This work aimed at evaluating the properties of the immobilization of rice husk in a cementitious matrix. Some properties of the waste form with incorporated rice husk were evaluated, as free water, workability, setting time and mechanical strength. The results indicated that cement matrices with 5 and 10% of biomass and water/cement ratio of 0.30 and 0.35 are viable for the production of waste forms that meets the Brazilian regulations.

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  • IPEN-DOC 24256

    POLO, IVÓN O. ; CALDAS, LINDA V.E. . Determination of transmission factors for an 85Kr beta radiation beam using an extrapolation chamber. In: LATIN-AMERICAN SYMPOSIUM ON NUCLEAR PHYSICS AND APPLICATIONS; WORKSHOPS ON NUCLEAR PHYSICS AND NUCLEAR RELATED TECHNIQUES, October 23-27, 2017, Havana, Cuba. Proceedings... 2017.

    Abstract: The 85Kr isotope is a beta-ray emitter (gas) with a half-life of 10.76 years. It is produced in the fission of Uranium and Plutonium. The origins of this isotope are the nuclear tests, the nuclear reactors and the reprocessing of nuclear fuel. In the gas release events around reactors, the 85Kr may represent a major hazard. In beta emitters, in order to evaluate the absorbed dose rate at different tissue depths, it is necessary to determine the transmission factors. In this work, the preliminary results of the determination of transmission factors of the 85Kr source of a BSS2 beta secondary standard are presented. For this purpose, an extrapolation chamber was used. The results obtained were considered acceptable, and they are within the uncertainties in comparison with the values provided by the source calibration certificate. The maximum difference between the results obtained in this work and those from the calibration certificate was 3.8%.

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  • IPEN-DOC 24440

    NORY, RENATA M. ; FIGUEIREDO, ANA M.G. . Análise da concentração de elementos potencialmente tóxicos em poeiras do túnel Jânio Quadros, na Cidade de São Paulo, Brasil / Potentially toxic elements in Jânio Quadros tunnel dusts from São Paulo city, Brazil. In: CONGRESSO BRASILEIRO DE GEOQUIMICA, 16., 22-25 de agosto, 2017, Búzios, RJ. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Geoquímica, 2017.

    Abstract: Poeiras urbanas são conhecidas transportadoras de substâncias potencialmente tóxicas, incluindo metais, que são introduzidas na atmosfera principalmente pela ação dos ventos, da ressuspensão de solos e das emissões industriais e veiculares. Por sua característica de potencial toxicidade, essas poeiras podem acarretar prejuízos tanto à saúde dos seres humanos quanto ao meio ambiente. Neste trabalho, foi determinada e quantificada a composição elementar de poeiras coletadas no túnel Jânio Quadros, no município de São Paulo, por meio de Análise por Ativação Neutrônica Instrumental. Os resultados mostraram valores de concentração elevados para os elementos Ba, Cr, Fe, Sb e Zn, superando os encontrados em estudos semelhantes, indicando potencial contaminação do ambiente estudado. Apontaram, ainda, diferenças significativas nas concentrações de acordo com o local de coleta e a granulometria, sendo que as frações mais finas tenderam a apresentar maiores concentrações. A análise de componentes principais aplicada aos dados indicou que os elementos As, Ba, Co, Sb e Zn possuem origem antrópica, possivelmente veicular.

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  • IPEN-DOC 24438

    MENEGHINI, ARTHUR A. ; DAMATTO, SANDRA R. ; OLIVEIRA, JOSELENE ; CARMO, AMANDA P. . Determinação da concentração de 226Ra, 228Ra e 210Pb e os efeitos da sazonalidade em águas mineirais da cidade de Caxambu, MG / Determination of the 226Ra, 228Ra and 210Pb concentration and the effects of seasonality in mineral waters of Caxambu. MG. In: CONGRESSO BRASILEIRO DE GEOQUIMICA, 16., 22-25 de agosto, 2017, Búzios, RJ. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Geoquímica, 2017.

    Abstract: Com o crescente aumento no consumo das águas minerais, a caracterização de sua composição e a regulamentação dessas águas são essenciais, por ser a água uma parte fundamental da dieta humana. Nessas águas, além dos elementos e compostos químicos estáveis que lhe conferem características físico-químicas, há também os radionuclídeos naturais que são responsáveis pela característica radioativa das mesmas. A utilização das águas minerais com objetivo medicamentoso é uma prática realizada no mundo todo; o Brasil abriga a maior estância hidromineral do mundo, o Parque das Águas de Caxambu, em Minas Gerais. O parque dispõe de 12 fontes de águas minerais, um balneário e também o único gêiser classificado no Brasil. O objetivo desse trabalho foi determinar a concentração de 226Ra, 228Ra e 210Pb nas águas minerais das fontes do Parque das Águas e verificar a influência da sazonalidade nos níveis de concentração desses radionuclídeos.

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  • IPEN-DOC 24433

    COUTINHO, SUELLEN N. ; FIGUEIREDO, ANA M.G. ; QUINAGLIA, GILSON A.. Estudo de bioacumulação de elementos potencialmente tóxicos em amostras de macrófitas aquáticas flutuantes do Reservatório Guarapiranga, São Paulo / Bioaccumulation of potentially toxic elements in floating aquatic macrophytes of Guarapiranga reservoir, São Paulo. In: CONGRESSO BRASILEIRO DE GEOQUIMICA, 16., 22-25 de agosto, 2017, Búzios, RJ. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Geoquímica, 2017.

    Abstract: Foram avaliados os teores dos elementos potencialmente tóxicos As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Se e Zn em quatro espécies de macrófitas flutuantes em três pontos do Reservatório Guarapiranga, com o objetivo de estimar a extensão da contaminação neste ambiente. Os resultados obtidos foram comparados a valores de referência para plantas aquáticas e a maioria dos elementos apresentou valores acima dos valores de referência. A ANOVA mostrou diferenças estatisticamente significativas entre os pontos de coleta, para a maioria dos elementos, indicando maior concentração dos elementos analisados no ponto localizado no braço do rio Embu Guaçu, um dos principais afluentes do reservatório. A análise estatística não indicou, em geral, diferenças em relação ao acúmulo dos elementos analisados entre as espécies de plantas. A análise de Componentes Principais (CP) sugere que os elementos As, Co, Cr, Hg, Ni, Pb e Se, inclusos na CP1, podem ser uma indicação de uma possível origem comum dos mesmos. A CP2 incluiu os elementos Cd, Cu e Zn. Deve-se ressaltar que o Cu tem sido aplicado frequentemente como algicida (sulfato de cobre) no reservatório e a CP3 incluiu apenas o Mn, sugerindo um comportamento diferenciado desse elemento.

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  • IPEN-DOC 24437

    LINO, JULIANA dos S. ; AQUINO, AFONSO R. de . Análise da evolução das áreas contaminadas no município de São Paulo. In: CONGRESSO BRASILEIRO DE GESTAO AMBIENTAL, 8., 27-30 de novembro, 2017, Campo Grande, MS. Anais... Rio de Janeiro, RJ: Instituto Brasileiro de Estudos Ambientais, 2017. p. 1-7.

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

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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.

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

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

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

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