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  • IPEN-DOC 26661

    CORREIA, M.M.; CHAMMAS, M.C.; ZAVARIZ, J.D.; ARATA, A. ; MARTINS, L.C.; MARUI, S.; PEREIRA, L.A.A.. Evaluation of the effects of chronic occupational exposure to metallic mercury on the thyroid parenchyma and hormonal function. International Archives of Occupational and Environmental Health, v. 93, n. 4, p. 491-502, 2020. DOI: 10.1007/s00420-019-01499-0

    Abstract: Introduction Experiments in animals exposed to mercury (Hg) in different chemical states have shown thyroid parenchymal and hormone alterations. However, these experiments did not allow the establishment of dose–response curves or provide an understanding of whether these Hg effects on the thyroid parenchyma occur in humans. Objective To evaluate the association between chronic occupational exposure to metallic Hg and alterations in thyroid hormones and gland parenchyma 14 years after the last exposure. Methods A cross-sectional study including 55 males exposed in the past to metallic Hg and 55 non-exposed males, paired by age, was conducted in the Hospital das Clínicas (Brazil) from 2016 to 2017. Serum concentrations of total and free triiodothyronine (TT3 and FT3), free thyroxine (FT4), thyrotropin (TSH), reverse T3 (RT3), selenium and antithyroid antibody titers were obtained. The Hg and iodine concentrations were measured in urine. The thyroid parenchyma was evaluated by B-mode ultrasonography with Doppler. The nodules with aspects suspicious for malignancy were submitted to aspiration puncture with a thin needle, and the cytology assessment was classified by the Bethesda system. The t test or Mann–Whitney test, Chi-square test and Spearman correlation were used to compare the exposed and non-exposed groups and examine the relationships between the variables. Univariate and multivariate logistic regression models were used to trace determinants of the risk of thyroid hormone alteration. Statistical significance was defined by p < 0.05. Results The urinary Hg average was significantly higher in the exposed group than in the non-exposed group (p < 0.01). The mean TSH serum concentration in the exposed group was higher, with a statistically significant difference between the groups (p = 0.03). Serum concentrations of TSH exceeded the normality limit (4.20 μIU/ml) in 13 exposed individuals (27.3%) and 4 non-exposed individuals (7.3%), with a statistically significant association between the hormonal increase and exposure to Hg (p = 0.02). In the logistic regression model, exposure to Hg (yes or no) showed an odds ratio = 4.86 associated with an increase of TSH above the normal limit (p = 0.04). The serum concentrations of RT3 showed a statistically borderline difference between the groups (p = 0.06). There was no statistically significant difference between the mean TT3, FT3 and FT4 serum concentrations in the Hg-exposed group compared to the non-exposed group. The proportions of the echogenicity alterations were higher in the exposed group compared to the non-exposed group (27.3% versus 9.1%; p = 0.03). Papillary carcinomas were documented in three exposed individuals and one non-exposed individual. A follicular carcinoma was recorded in one non-exposed individual. Conclusions Due to the higher serum TSH concentration and the prevalence of parenchymal alterations in the Hg-exposed group, even after cessation of exposure, it is recommended that the thyroid status of exposed workers be followed for a long period.

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  • IPEN-DOC 26459

    SAUEIA, CATIA H.R. ; NISTI, MARCELO B. ; SILVA, PAULO S.C. da ; OLIVEIRA, JONATHAN P. de ; MAZZILLI, BARBARA P. . Lixiviation of rare earth elements in tropical soils amended with phosphogypsum. International Journal of Environmental Analytical Chemistry, v. 100, n. 6, p. 675-685, 2020. DOI: 10.1080/03067319.2019.1638918

    Abstract: In Brazil, the main producers of phosphate fertilisers are responsible for the production of approximately 12 million tons of phosphogypsum (PG) per year. This phosphogypsum has been used for many years in agriculture as a soil amendment. For its safe long-term application, it is necessary to characterise the impurities present in phosphogypsum and to study the leaching or dissemination of such impurities to waters or other ecosystem compartments. This paper aims to evaluate the availability of Rare Earth Elements (REEs): La, Ce, Nd, Sm, Eu, Tb and Lu. The technique used for the determination of the elements of interest in the soil, soil mixed with PG, PG and leachate was the instrumental neutron activation analysis. For this purpose, an experiment was carried out, in which columns filled with sandy and clay Brazilian typical soils mixed with phosphogypsum were percolated with water, to achieve a mild extraction of these elements. The results showed that the ƩREE in PG was in the order of 7,600 mg kg−1 while in the leachate, the sum was in the order of 100 μg L−1 results obtained for the available fraction obtained was below 1%, giving evidence that although the REEs are present in the PG in higher concentrations, they are not available to the water. It can be concluded that the addition of PG to the soils does not contribute to a significant enhancement of the REEs in water.

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  • IPEN-DOC 25762

    BARTOLOMEI, SUELLEN S. ; SANTANA, JULYANA G. ; DIAZ, FRANCISCO R.V.; KAVAKLI, PINAR A.; GUVEN, OLGUN; MOURA, ESPERIDIANA A.B. . Investigation of the effect of titanium dioxide and clay grafted with glycidyl methacrylate by gamma radiation on the properties of EVA flexible films. Radiation Physics and Chemistry, v. 169, p. 1-9, 2020. DOI: 10.1016/j.radphyschem.2018.08.022

    Abstract: Many studies report that nanocomposites obtained by dispersion of a small amount nanofiller into the polymer have remarkable improvements achieved in the mechanical and physical properties. However, in order to achieve this great improvement in properties, it is necessary that the nanofillers be dispersed homogeneously into the polymeric matrix. Often this dispersion is difficult to achieve due to the high interfacial energy of the nanoparticles present. This study reports the effect of gamma irradiation induced graft of glycidyl methacrylate (GMA) onto the surface of TiO2 and Clay nanofillers to improve their dispersion into the EVA matrix. The physical and mechanical properties of Ethylene-vinyl acetate copolymer (EVA) flexible films with these nanoparticles were studied. EVA nanocomposite with adding of the different amount of TiO2 and modified montmorillonite clay grafted and un-grafted with glycidyl methacrylate (GMA) using gamma irradiation have been prepared by melt extrusion. The nanocomposite flexible films were produced using a flat die extrusion process. The PGMA-grafted nanofillers were characterized by XRD and TEM analysis. The flexible films were characterized by Tensile tests, ATR–FTIR, UV–VIS, XRD, TG, and FE-SEM analysis to understand the nature of the interaction between the nanofillers and EVA matrix. The results showed that the addition of PGMA-grafted TiO2 and Clay nanofillers into EVA matrix improved the bonding between the nanofillers and matrix. It was also found that the PGMA-grafted nanofillers could be well dispersed into an EVA matrix in contrast to that of un-grafted. The tensile strength and modulus of the resulting EVA/TiO2-PGMA enhanced in comparison to that of un-grafted TiO2. The EVA/Clay-PGMA had slightly decreased tensile strength comparable to that of EVA/Clay but had considerably improved elastic modulus. In addition, the flexible films based on TiO2 exhibited high UV–Vis light absorption with energy gap shifted to the visible region. The results demonstrated that TiO2 and Clay nanofillers grafted with GMA by gamma radiation can be used to prepare EVA flexible films with improved bonding between the nanofillers and matrix and, consequently, enhanced properties for food and cosmetic packaging application.

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  • IPEN-DOC 25091

    FAZOLIN, GABRIELA N. ; VARCA, GUSTAVO H.C. ; KADLUBOWSKI, SLAWOMIR; SOWINSKI, SEBASTIAN; LUGAO, ADEMAR B. . The effects of radiation and experimental conditions over papain nanoparticle formation: towards a new generation synthesis. Radiation Physics and Chemistry, v. 169, p. 1-8, 2020. DOI: 10.1016/j.radphyschem.2018.08.033

    Abstract: Papain is a natural enzyme extracted from the fruit of Carica papaya Linnaeus, successfully applied in the pharmaceutical area as a drug carrier and debridement agent for wounds. In recent studies papain nanoparticles were synthesized and crosslinked with the use of ionizing radiation in the search for biopharmaceutical advantages as well as the development of bioactive nanocarriers. This study addresses the effects of buffer molarity and irradiation conditions on papain nanoparticles formation. Nanoparticles were synthesized on ice bath using ethanol (20%, v/v) as a cosolvent and crosslinked by gamma radiation using a 60Co source. Experimental variables included the synthesis in deionized water and in 1, 10, 25 and 50mM phosphate buffer, under different temperatures of −20 °C, 0 °C and 20 °C before and throughout the irradiation period, and using radiation dose rates of 0.8, 2, 5 and 10 kGy h−1 to reach the dose of 10 kGy. Proteolytic activity was quantified using Nα- benzoyl-DL-arginine-p-nitroanilide hydrochloride. Nanoparticle size and crosslinking by means of bityrosine were evaluated by dynamic light scattering and fluorescence measurements, respectively. Buffer molarity and radiation dose rate were identified to influence bityrosine formation and proteolytic activity without impacting nanoparticle size. Variations in temperature impacted bityrosine formation exclusively. Optimized conditions for papain nanoparticle synthesis were achieved using 50mM phosphate buffer at the dose rate of 5 kGy h−1 and temperature of 0 °C throughout the process.

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  • IPEN-DOC 26861

    ROSSI, WAGNER de ; VIEIRA, ALEXANDRE. Texturisation of engine components with shaped ultrashort laser pulses. In: INTERNATIONAL CONGRESS ON LASER ADVANCED MATERIALS PROCESSING, 8th; INTERNATIONAL SYMPOSIUM ON LASER PRECISION MICROFABRICATION, 20th; INTERNATIONAL SYMPOSIUM ON HIGH POWER LASER PROCESSING, 8th, May 21-24, 2019, Hiroshima, Japan. Abstract... Osaka, Japan: Japan Laser Processing Society, 2019.

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  • IPEN-DOC 26860

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

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

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  • IPEN-DOC 26859

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

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

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  • IPEN-DOC 26858

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

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

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  • IPEN-DOC 26857

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

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

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  • IPEN-DOC 26856

    BOAS, CRISTIAN W.V. ; SILVA, JEFFERSON de J. ; BENEDETTO, RAQUEL ; MENGATTI, JAIR ; ARAUJO, ELAINE B. de . 177Lu-PSMA-617: Brazilian experience. Journal of Nuclear Medicine, v. 60, supplement 1 200, 2019.

    Abstract: Introduction: PSMA-617 radiolabeled with lutetium-177 has shown good results in compassionate studies around the world, and there is great interest in this kind of therapy in Brazil. The Nuclear and Research Institute (IPEN-CNEN) in São Paulo city, is a national radiopharmaceutical producer and the distribution of radiopharmaceuticals for therapy in a country of continental dimensions such as Brazil, becomes a challenge from the standpoint of guaranteeing the stability of the product. This work evaluated the scheduling of pilot batches for the production of 177Lu-PSMA-617 and studied the effect of dilution and freezing on the stability of mono-doses of the product. Materials and Methods: Radiolabeling of PSMA-617 (ABX, Germany) with lutetium-177 (JSC, Russia) was performed in heating block at 90 °C for 30 minutes, 37 GBq (1 Ci), 500 μg of peptide and sodium ascorbate (0,5 M pH 4,7) as buffer. At the end of the radiolabel, 0,5 mL of DTPA solution (4 mg/mL pH 4,5) was added and the product was diluted with an appropriate volume of saline solution 0,9%. The final product was filtrated in 0.22 membrane and the doses were fractionated (7,4 GBq calibrated for 24 hours in approximately 2,4 mL) and conditioned in appropriate lead chambers inside a dry ice bucket for transport simulation. The radiochemical purity (RP) was evaluated in a stability study at, 24 and 48 hours by TLC and HPLC. The radionuclidic purity, sterility and bacterial endotoxins were also evaluated. Results and discussion: The radiopharmaceutical was stable after 48 hours (99.47% TLC and 99.39% HPLC), and was approved in radionuclidic, sterility and endotoxins assays. The vials fractionated in mono-doses calibrated for 24 hours showed high stability through freezing and dilution, which allowed the transportation to the Cancer Hospital of Barretos, distant 420 km from the production center in São Paulo. All these mono-doses were administrated to the patients after 24 hours of the production. Also, these results denote that is possible to scale up this production until 74 GBq and be used in a clinical trial that is being planned. Conclusions: These carried out experiments demonstrated that it is possible to produce 177Lu-PSMA-617 for use in clinical trials in Brazil. Until now, four patients are under treatment (compassionate use). Also, these results demonstrate that it is still possible to increase production activity to 74 GBq, just like is normally done with 177Lu-DOTATATE.

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  • IPEN-DOC 26855

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

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

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  • IPEN-DOC 26854

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

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

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  • IPEN-DOC 26853

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

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

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  • IPEN-DOC 26852

    FRIMAIO, AUDREW . Desenvolvimento de compostos termoplásticos ou termofixos radiologicamente equivalentes ao tecido humano / Development of thermoplastic or thermosets compounds radiologically equivalent to human tissue . 2019. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. p. Orientador: Letícia Lucente Campos Rodrigues. DOI: 10.11606/T.85.2020.tde-06022020-104210

    Observação: Acesso restrito até 31/12/2022

    Abstract: Os objetos simuladores constituídos de material tecido equivalente, são utilizados em laboratórios de pesquisa e em ambientes clínicos como parte de rotinas de controle de qualidade e radioproteção, são fundamentais para evitar a exposição de pessoas a doses de radiação. Os objetos simuladores são, na grande maioria, importados e de alto custo. Materiais radiologicamente equivalentes aos tecidos humanos, tem como principal requisito possuir o número atômico efetivo e/ou coeficiente de atenuação linear aproximadamente igual ao do tecido que se quer simular, de modo a reproduzir as suas características de atenuação à radiação ionizante incidente. Neste trabalho foram desenvolvidos compostos e protótipos que suprem a necessidade deste tipo de material radiologicamente equivalente a tecido utilizando tecnologia nacional. Os protótipos desenvolvidos e produzidos contêm substâncias, encontradas comercialmente, que, ao formarem um composto, seus percentuais são equivalentes aos encontrados no corpo humano, tais como tecido mamário, tecido mole, tecido adiposo e água A formulação dos compostos foi realizada por simulação computacional em trabalho realizado anteriormente, visando a produção de placas e/ou objetos (protótipos) com características de transmissão equivalentes ao de tecidos humanos e/ou à água. Os testes de desempenho dos protótipos produzidos apontaram as melhores formulações para aplicação em objetos simuladores na área de diagnóstico por imagem.

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  • IPEN-DOC 26851

    MADI, LILIAN L.N. ; SORDI, GIAN-MARIA A.A. ; ARAUJO, EDMIR N. de. Nuclear state liability for damage resulting from nuclear activities. RAP Conference Proceedings, v. 4, p. 61-66, 2019. DOI: 10.37392/RapProc.2019.13

    Abstract: Much has already been seen in the world regarding the damage that may result from an accident in nuclear power plants. In the event of an accident that causes effective damage, either to the environment or to the population, both the Brazilian and foreign standards predict liability for remedying. The Brazilian Federal Constitution of 1988 determines the competence of the Union to operate nuclear services and installations, being State monopoly activities related to nuclear material and its derivatives. Besides that, FC/88 attributed liability stricto sensu for nuclear damage. The Vienna Convention on Civil Liability for nuclear damage, dated May 21, 1993, which was promulgated in Brazil by Decree No. 911/1993, provides that the operator is responsible for nuclear damages, in the case of Brazil, the operator is the State entity (Federal Autarchy) responsible for the operation. Thus, in cases of nuclear damage, the State should be held liable objectively. And here issues begin to arise such as: Is the State always responsible? Is there any possibility of exclusion of the State’s liability? This paper aims to analyze the constitutional text and the infra-constitutional rules in an attempt to answer these and other questions without, however, intending to exhaust the subject.

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  • IPEN-DOC 26850

    PEREIRA, MARIA da C.C. ; MADI FILHO, TUFIC ; BERRETTA, JOSE R. ; TOMAZ, LUCAS F. ; MADI, MIRIAM N. . Optical properties and radiation response of Li ion-doped CsI scintillator crystal. RAP Conference Proceedings, v. 4, p. 131-135, 2019. DOI: 10.37392/RapProc.2019.26

    Abstract: Scintillators are materials that convert the energy of ionizing radiation into a flash of light. Due to the existence of different types of scintillators, they are classified into three groups according to their physicochemical characteristics, namely, inorganic, organic and gaseous scintillators. Among the inorganic crystals, the most frequently used as scintillator consist of alkali metals, in particular alkaline iodides. Scintillation materials have many applications, for instance in medical imaging, security, physics, biology, non-destructive inspection and medicine. In this study, lithium doped CsI scintillator crystals were grown using the vertical Bridgman technique. The concentration of the lithium doping element (Li) studied was 10-4 M to 10-1 M. Analyses were carried out to evaluate the developed scintillators with regard to luminescence emission and optical transmittance. The luminescence emission spectra of these crystals were measured with a monochromator for gamma radiation from 137Cs source excitation. The determination of the dopant distribution along the crystalline axis allowed the identification of the region with Li concentration uniformity, which is the region of the crystalline volume indicated for use as a radiation detector. The crystals were excited with neutron radiation from AmBe source, with the energy range of 1 MeV to 12 MeV. 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. Accordingly, experiments were performed using gamma radiation in the energy range of 59 keV to 1333 keV in order to verify the ability of the detector to discriminate the presence of different types of radiation.

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  • IPEN-DOC 26849

    MADI FILHO, TUFIC ; PEREIRA, MARIA da C.C. ; BERRETTA, JOSE R. ; TOMAZ, LUCAS F. ; MADI, MIRIAM N. . Study and development of neutron detectors using doped CsI crystals. RAP Conference Proceedings, v. 4, p. 117-121, 2019. DOI: 10.37392/RapProc.2019.23

    Abstract: The development of new radiation detectors using scintillation crystals, which increase response speed, dose and energy accuracy and, at the same time, the feasibility of simplifying and reducing costs in the production process are always necessary. In the CTR-IPEN laboratory, pure and doped CsI crystals were grown using the Bridgman technique. This work shows the obtained results using a doped CsI scintillator with the converters: Br, Pb, Tl, Li as alpha, beta, gamma and neutron detectors.

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  • IPEN-DOC 26848

    MADI, LILIAN ; SORDI, GIAN-MARIA ; ARAUJO, EDMIR. Nuclear state liability for damage resulting from nuclear activities. In: JAKSIC, ALEKSANDAR (Ed.); KARAMARKOVIC, JUGOSLAV (Ed.) INTERNATIONAL CONFERENCE ON RADIATION APPLICATIONS, September 16-19, 2019, Belgrade, Serbia. Abstract... Niš, Serbia: Sievert Association, 2019. p. 91-91.

    Abstract: Nowadays much is discussed about issues related to the preservation of the environment, what can be done to improve it, what should be avoided. In this discussion comes the question of the potential of nuclear energy. One of them is the potential for electric power generation, more cheaply and with less impact to the environment. However, much has already been seen in the world as regards damages that may result from an accident in these plants. In the event of an accident that causes effective damage, either to the environment or to the population, both the Brazilian and foreign standards as predict liability for remedying. The Brazilian Federal Constitution of 1988 determines the competence of the Union to operate nuclear services and installations, being State monopoly activities related to nuclear material and its derivatives. Besides that, CF/88 attributed liability strictu senso for nuclear damage. The Vienna Convention on Civil Liability for nuclear damage, dated May 21, 1993, which was promulgated in Brazil by Decree No. 911/1993, provides that the operator is responsible for nuclear damages, in the case of Brazil, the operator is the State entity (Federal Autarchy) responsible for the operation. Thus, in cases of nuclear damage the State should be held liable objectively. And here issues begin to arise such as: Is the State always responsible? Is there any possibility of exclusion the State liability? This paper aims to analyze the constitutional text and the infra-constitutional rules, correlating the nuclear and environmental legislation to respond to these and other questions.

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  • IPEN-DOC 26847

    COSTA, PRISCILA ; RAELE, MARCUS P. ; DOMIENIKAN, CLAUDIO ; COSTA, FABIO E. ; MADI FILHO, TUFIC ; ZAHN, GUILHERME S. ; GENEZINI, FREDERICO A. . A compact electronic system for a photodiode neutron detector. In: JAKSIC, ALEKSANDAR (Ed.); KARAMARKOVIC, JUGOSLAV (Ed.) INTERNATIONAL CONFERENCE ON RADIATION APPLICATIONS, September 16-19, 2019, Belgrade, Serbia. Abstract... Niš, Serbia: Sievert Association, 2019. p. 36-36.

    Abstract: The demand for portable neutron detectors is on the rise, and for that purpose, low cost boron-10 has been frequently used instead of helium-3, which is usually employed in large and expensive detectors. Portable detectors are of interest in some applications, such as neutron dosimeters or inspection systems targeted in the detection of fissile material and drugs in airports. In this work a portable thermal neutron detection system was developed which is based on a commercial silicon photodiode coupled to a boron converter; this prototype is then plugged into a portable electronic system. The boron layer was produced by pulsed laser deposition, either on a thin glass slide or on the photodiode itself. The boron deposition in the photodiode was made directly in the active area of the detector, so before and after the deposition process a characterization of the device regarding both the dark current and the operation voltage was performed using an americium source. Finally, both configurations were tested. The neutron detection process occurs by detecting the alpha and lithium particles produced by the interaction of the incoming neutron with the boron-10 nuclides. These heavy ions then interact with the active area of the reverse-biased photodiode, producing an electric signal that has to be preamplified and then properly amplified by the portable electronic system, which in turn produces an output that can either be sent to a multichannel analyzer or to a digital counter. The integrated circuit of the low noise preamplifier transforms the detector’s current pulse into a voltage pulse with amplitude proportional to the charge carried by the current pulse. The shaper-driver consists of a differentiator and an integrator and is responsible for filtering and further amplifying the preamplifier signal, generating a NIM-compatible energy output pulse. The performance of the photodiode-amplifier set for alpha particles was successively tested using a 243Am radioactive source. Initial tests were made using the boron-deposited glass, and the electronic signal was properly read. However, when the same system was tested using the boron deposited directly in the photodiode, the output signal couldn’t be read, due to the fact that during the deposition process there was an increase in the dark current and a decrease in the operation bias. In this way, a new portable electronic system was developed using a hybrid integrated amplifier circuit. This new electronic setup allowed the use of both configurations, and was tested both with alpha-emitting Americium and neutron-emitting AmBe sources. In conclusion, both portable electronic systems have proven suitable for the thermal neutron detector developed.

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  • IPEN-DOC 26846

    PEREIRA, MARIA da C.C. ; MADI FILHO, TUFIC ; BERRETTA, JOSE R. ; TOMAZ, LUCAS F. ; MADI, MIRIAM N. . Optical properties and radiation response of Li ion-doped CsI scintillator crystal. In: JAKSIC, ALEKSANDAR (Ed.); KARAMARKOVIC, JUGOSLAV (Ed.) INTERNATIONAL CONFERENCE ON RADIATION APPLICATIONS, September 16-19, 2019, Belgrade, Serbia. Abstract... Niš, Serbia: Sievert Association, 2019. p. 15-15.

    Abstract: Scintillators are materials that convert the energy of ionizing radiation into a flash of light. Due to the existence of different types of scintillators themselves, they were classified into three groups according to their physicochemical characteristics, namely, inorganic, organic and gaseous scintillators. Among the inorganic crystals, the most used as scintillator are constituted of alkali metals, in particular alkaline iodides. Scintillation materials are used in many applications, such as medical imaging, security, physics, biology, non-destructive inspection and medicine. In this work, lithium doped CsI scintillator crystals were grown using the vertical Bridgman technique. The concentration of the lithium doping element (Li) studied was 10-4 M to 10-1 M. Analyses were carried out to evaluate the scintillators developed concerning to luminescence emission and optical transmittance. The luminescence emission spectra of these crystals were measured with a monochromator for gamma radiation from 137Cs source excitation. The optical transmittance measurements were made in the CsI;Li crystal, in a spectral region of 200 nm to 1100 nm. Determination of the dopant distribution along the crystalline axis, allowing to identify the region with Li concentration uniformity, which is the region of the crystalline volume indicated for use as radiation detector. The crystals were excited with neutron radiation from AmBe source, with energy range of 1 MeV to 12 MeV. As with neutron sources also generate gamma radiation, which can interfere with the measurement, it is necessary that detector be able to discriminate the presence of such radiation. Accordingly, experiments were performed using gamma radiation in the energy range 59 keV to 1333 keV in order to verify the ability of the detector to discriminate the presence of different types of radiation.

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  • IPEN-DOC 26845

    MADI FILHO, TUFIC ; PEREIRA, MARIA da C.C. ; BERRETTA, JOSE R. ; TOMAZ, LUCAS F. ; MADI, MIRIAM N. . Study and development of neutron detectors using doped CsI crystals. In: JAKSIC, ALEKSANDAR (Ed.); KARAMARKOVIC, JUGOSLAV (Ed.) INTERNATIONAL CONFERENCE ON RADIATION APPLICATIONS, September 16-19, 2019, Belgrade, Serbia. Abstract... Niš, Serbia: Sievert Association, 2019. p. 14-14.

    Abstract: In the development of nuclear radiation detectors one must take into consideration the process of interaction of the radiation under study with matter. In the case of neutron detectors it must be considered that the detection of neutrons is not trivial in view of the lack of charges of these particles and the peculiarity of their interactions with matter. Another difficulty in the detection of neutrons consists in the discrimination of the electronic impulses generated by the neutrons of those generated by other radiations, almost always present. The main propositions of neutron-sensitive detectors consist of gaseous detectors, scintillators and semiconductors. These detectors intrinsically are not sensitive to neutrons, so they need a radiation converter based on nuclear reactions of the type: Neutron + Converter -> Detectable radiation. Some reactions with neutrons are more used, such as: 10B (n, α), 6Li (n, α) and 3He (n, p). Neutron-scintillation crystal are being the object of active research in several research centers and having their implementations in several applications. The development of new radiation detectors using scintillation crystals, which increases response speed, dose and energy accuracy and, at the same time, the feasibility of simplifying and reducing costs in the production process is always necessary. In the CTR-IPEN laboratory, pure and doped CsI crystals were grown using the Bridgman technique. This work shows the obtained results using doped CsI scintillator with the converters: Br, Pb, Tl, Li as neutron detectors.

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  • IPEN-DOC 26844

    RODRIGUES, ANTONIO C.I. ; MADI FILHO, TUFIC ; SILVA, DAVILSON G. da . Core modeling of the research reactor IEA-R1 with the MCNP-6.2 computational code. In: JAKSIC, ALEKSANDAR (Ed.); KARAMARKOVIC, JUGOSLAV (Ed.) INTERNATIONAL CONFERENCE ON RADIATION APPLICATIONS, September 16-19, 2019, Belgrade, Serbia. Abstract... Niš, Serbia: Sievert Association, 2019. p. 13-13.

    Abstract: The objective of this work is to develop the modeling of the IEA-R1 reactor core with the MCNP-6.2 computational code that was recently acquired. The main advantage of this new version of the code is the performance of burnup calculations of the fuel elements. This modeling will be valid by comparing the thermal and epithermal neutron flux obtained in the calculations with the MCNP-6.2 and the fluxes measured with the activation of gold foils (Au) with and without cadmium coating (Cd) in the same positions of irradiation and, with the same arrangement of fuel elements in the reactor core. After the validation of this model, the idea is to use it for the burnup calculations of the fuel elements that are fundamental for a correct management of the reactor core. Currently, the management of the core is carried out by deterministic codes that are very old and have many approximations leading to very conservative results, for example, TWODB, HAMMER, and CITATION.

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  • IPEN-DOC 26843

    VICENTE, MARCOS A.A.H.; MUNHOZ JUNIOR, ANTONIO H.; MIRANDA, LEILA F. de; SARMENTO, BRUNO F.C.C.; BERNUSSI, AYRTON; OLIVEIRA, RENE ; RIBEIRO, ROBERTO R.; MORAES, DENISON A.. Use of pseudoboehmite for drug delivery system of simvastatin. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 687-688.

    Abstract: Simvastatin is a well known anti-cholesterol drug that is commercially available in Brazil in various strengths including Simvastatin Tablets, with 10, 20 and 40 mg. Simvastatin is a drug, which is used for treating patients with hypercholesterolemia, in order to prevent atherosclerosis, cardiovascular disease, and stroke1. Today cardiovascular disease is still the leading cause of death worldwide. It should also be noted that the treatment of cardiovascular diseases was responsible for just over a third of what the Brazilian federal government disbursed between the years 2013 and 2016 in the purchase of medicines for the population. However, the side effects of simvastatin include muscle pain and liver problems. When diet and exercise are not enough to reduce cholesterol levels, drugs as simvastatin are the medication prescribed. One problem of simvastatin is the low solubility. Simvastatin is practically insoluble in water (30 μg/mL), and 0.1 M HCl (60 μg/mL) [1,2,3]. This paper presents pseudoboehmite nanoparticles synthesized via sol-gel process. The pseudoboehmite were synthesized by an ethanol/water sol–gel method using aluminum nitrate as precursos and sodium hydroxide. The pseudoboehmite with simvastatin entrapped was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) using secondary electrons detector and EDS detector, thermal analysis (thermogravimetric analysis and differential thermal analysis) and Fourier transform infrared spectrometer (FTIR). The data shows that the simvastatin was incorporated homogenously in the pseudoboehmite. The Fourier transform infrared analysis shows that there was no degradation of the drug.

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  • IPEN-DOC 26842

    PIERETTI, EURICO F. ; NEVES, MAURICIO M. das ; CORREA, OLANDIR V. ; ANTUNES, R.A.. Tribological evaluation of CoCrMo alloy for biomedical applications. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 1836-1836.

    Abstract: The tribological behavior of the CoCrMo alloy was evaluated in the air in a nanotribometer. The chemical composition, microstructure and mechanical properties of CoCrMo alloys makes them potential materials for use as implantable medical or dental devices [1]. This work has a specific focus on covering the possible in vitro wear modes seen on metal-on metal surfaces. Ballcratering wear test was carried out for 10 min with a solid sphere of WC as counterbody, at a frequency of 75 rpm [2]. The CoCrMo samples’ citotoxicity was analyzed in order to determine if the alloy casting process and its surface finishing, current used in industry, affects the biomaterial’s biocompatibility. All tested surfaces were prepared according to the recommendations for clinical use. The results address the potential detrimental effects of hard particles in vivo such as increased wear rates (debris generation), which is greatly influenced by the normal force, and corrosion (metal-ion release). None sample was considered cytotoxic.

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  • IPEN-DOC 26841

    VIVEIROS, BARBARA V.G. de ; BERBEL, LARISSA O. ; BUGARIN, ALINE F.S. ; DONATUS, UYIME ; COSTA, ISOLDA . The corrosion resistance between AA2050-T84 and AA7050-T7451 welded by friction stir weld. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 2089-2089.

    Abstract: Aluminum alloys of the 2XXX and 7XXX series are among the most used materials in the aerospace industry. These alloys have good mechanical, specific strength and corrosion resistance, and for the 2XXX series, further reduction in density can be achieved by lithium addition. So, in this case, it can reduce the weight of the aeroplane and fuel usage leading to the minimization of CO 2 emissions and cost savings. Aluminum alloys have poor weldability, and to use these alloys for aeroplane structures, joining is unavoidable. To make this, the industry uses rivets to join these alloys. But rivets increase the mass of aeroplanes, and to minimise this, a non-fusion (unconventional) welding technique capable of welding aluminium alloys easily was developed. This new technique is friction stir welding, which exposes the aluminum alloys to thermomechanical effects, changing the microstructure of the alloys, and resulting in different regions with different metallurgical and mechanical properties. An example of the regions is the thermomechanically affected region which experiences both plastic deformation and high temperature but without recrystallization. There is also the stir zone which is the region of recrystallized grains, the heat affected zone and the base metal (that is not affected by the welding process). The goals of this work are to analyze the corrosion resistance of the friction stir weldment of dissimilar AA2050-T84 and AA7050-T7451 alloys using electrochemical tests, characterizing the different regions of the weldment, and establishing the most susceptible region to corrosion using a sodium chloride solution.

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  • IPEN-DOC 26840

    QUEIROZ, CARLOS A. da S. . Synthesis and characterization of praseodymium acetate for use in nanotechnology. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 2554-2555.

    Abstract: A simple and economical chemical process to obtaining praseodymium acetate of high purity is studied. The raw material in the form of mixed rare earths carbonate comes from an industrial separation of rare earths, thorium and uranium in the Brazilian monazite. It is used the technique of strong cationic exchange resin, proper to water treatment, to the praseodymium's fractionation and it is achieved a purity of 99.9% in Pr6O11 and yield greater than or equal 80%, with the elution by EDTA solution in pH controlled. The complex of EDTApraseodymium is transformed in praseodymium oxide, subsequently the oxide is dissolved in acetic acid to obtain the praseodymium acetate. The solid salt was characterized via chemical analysis, thermal analysis, X ray diffraction and infrared spectroscopy. In summary the analytical data collected allowed to conclude that stoichiometric formula for the praseodymium acetate obtained is Pr(CH3COO)3.1.5H2O. The molecular absorption spectrophotometry technique is used to monitoring the praseodymium content during the process and mass spectrometry to certification the purity of the praseodymium acetate. The typical praseodymium acetate contain the followings contaminants in micrograms per gram: Y( 20 ), Sc ( 18 ), La ( 6 ), Ce ( 26 ), Nd ( 3 ), Sm ( 18 ), Eu ( 17 ), Gd (19 ), Tb ( 16 ), Dy (17 ), Ho ( 18 ), Er (18 ), Tm ( 16 ),Yb ( 17 ), Lu ( 17.0), Lu ( 17 ).

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  • IPEN-DOC 26839

    RIBEIRO, ELOANA P. ; FARNEZE, STELLA K. ; COUTO, ANTONIO A. . Shot peening surface treatment effect in 316L stainless steel surface modification. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 216-216.

    Abstract: Stainless steel 316L (low carbon) is the most widely used steel as biomaterial. This metal has low toughness, so metallic implants are prone to wear [1]. Residual compressive stress and surface toughness increase can improve materials life fatigue, as a tough layer prevents plastic deformation. Materials failure, as fatigue and wear, are related to materials surface properties and structure [1]. Shot peening is a mechanical surface treatment in which many small spheres are accelerated and blasted in materials surface to promote impacts with sufficient energy to generate plastic deformation. The main aim of this technique is to induce residual compressive stress on materials surface, increasing wear properties and toughness. Surgical implants are submitted to this treatment to generate surface roughness increase for better adhesion too [2]. In this work, shot peening was performed using four different conditions to verify the effect on surface modification. Microscope techniques, x-ray diffraction, residual stress, toughness and roughness measurements were used to validate the tests. In conclusion, shot peening is an effective surface treatment to induce residual stress and increase roughness and toughness in 316L stainless steel.

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  • IPEN-DOC 26838

    RIBEIRO, E.P. ; FARNEZE, S.K. ; COUTO, A.A. . Shot peening effect in F138 stainless steel surface modification. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Resumo expandido... São Carlos, SP: Aptor Software, 2019. p. 2632-2634.

    Abstract: Stainless steel F138 is the most widely used steel as biomaterial. This metal has low toughness, so metallic implants are prone to wear [1]. Residual compressive stress and surface toughness increase can improve materials life fatigue. Shot peening is a mechanical surface treatment in which many small spheres are accelerated and blasted in materials surface, inducing residual compressive stress on materials surface. Surgical implants are submitted to this treatment to generate surface roughness increase for better adhesion too [2]. In this work, shot peening was performed using four different conditions to verify the effect on surface modification. Microscope techniques, x-ray diffraction, residual stress, toughness and roughness measurements were used to validate the tests. In conclusion, shot peening is an effective surface treatment to induce residual stress and increase roughness and toughness. Keywords: F138, Residual Stress, Shot Peening, Stainless Steel.

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  • IPEN-DOC 26837

    ROSSI, MARIANA C.; BAYERLEIN, DANIEL L. ; BRANDÃO, JAQUELINE de S.; PFEIFER, JOÃO P.H.; ROSA, GUSTAVO dos S.; KRIECK, ANDRE M.T.; MARTINEZ, LUIS G. ; SAEKI, MARGARIDA J.; ALVES, ANA L.G.. Preparation of porous ternary alloy Ti-34-Nb-6Sn / Mg for the implant. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 1042-1042.

    Abstract: Titanium alloys are designed in order to provide attractive mechanical properties, including Young's modulus, high mechanical strength and biocompatibility [1]. These properties are achieved when titanium structured under β phase, and the selection of non-toxic beta-stabilizing metals is important for the improvement of the alloys. In order to create a good interaction at the bone-implant interface, it is interesting that these biomaterials also have adequate porosities for the bone cells to adhere on its surface, and the bone tissue to grow around the prosthesis. Thus, the purpose of this work was to produce the Ti-34-Nb-6Sn alloy by the powder metallurgy technique allied to the magnesium space holder. After the synthesis, the structure of the material was characterized by X-ray diffractometry (XRD) and its morphological and compositional analysis, carried out by Scanning Electron Microscopy (SEM) and X-ray dispersive energy (EDX). The apparent porosity analysis was made by the Archimedes method. In the biological assay, stem cells derived from equine bone marrow were seeded on the surface of the materials in order to obtain information about cytotoxicity and cell adhesion. The results of XRD and MEV confirmed the formation of the alloy (PDF: 25-977), being that the proportion of phase β was greater than the phase α (PDF: 44-1288,41-1352), and the evaporation of Mg, as well as a significant increase of porosity, which was also confirmed by the Archimedes method. Additionally, according to SEM, the cells showed good adhesion on the surface of the material, as well as inside the formed pores. According to the techniques used, it was then possible to obtain β phase rich titanium alloy with significant porosity on which the cells adhered satisfactorily.

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  • IPEN-DOC 26836

    BOTTA, WALTER J.; LEAL NETO, RICARDO M. ; JORGE JUNIOR, ALBERTO M.; ZEPON, GUILHERME; ISHIKAWA, TOMAZ T.; BOLFARINI, CLAUDEMIRO; KIMINAMI, CLAUDIO S.; LEIVA, DANIEL R.. Mg-based composites for hydrogen storage. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 47-48.

    Abstract: Magnesium hydride can be already considered as the traditional hydrogen storage material despite some unanswered fundamental questions concerning its properties. These questions concern the understanding of the activation (or first hydrogen absorption) step, the role of the additives in the absorption / desorption kinetics and the synergy between phases in the absorption / desorption kinetics, in the case of composites systems. Recent results indicated that modifications of conventional processing routes to synthesize hydride-forming systems might have a strong role in the hydrogen storage behavior of different metals and compounds. The present work shows results of Mg-TiFe and Mg-LaNi5 composites that have been produced by new approaches of the usual techniques, such as high-energy ball milling (HEBM) and cold rolling (CR) under inert atmosphere. Structural characterization was carried out by X-ray diffraction (XRD) and scanning and transmission electron microscopy (SEM and TEM). H-absorption / desorption kinetics were measured in a Sievert’stype apparatus and by differential scanning calorimetry (DSC) coupled with thermogravimetric analysis (TGA) and mass spectrometry (QMS). MgH2 hydride was formed at room temperature in Mg-TiFe composites produced by HEBM, in this case with an important improvement in the hydrogen absorption kinetic as compared with pure Mg. MgH2-LaNi5 composites were prepared by cold rolling under an inert atmosphere and the composite presented faster hydrogen absorption/desorption kinetics and reduced desorption temperatures in comparison to MgH2. These results are discussed in view of the above fundamental questions, in particular considering the possible synergy between Mg and the second phase (TiFe or LaNi5) in the modification of absorption and desorption kinetics.

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  • IPEN-DOC 26835

    LAZARIN JUNIOR, ELOI; MUNHOZ JUNIOR, ANTONIO H.; MIRANDA, LEILA F. de; SARMENTO, BRUNO F.C.C.; BERNUSSI, AYRTON; LIMA, NELSON B. de ; ROSSI, MAURA V.; PERES, RENATO M.; FLORENCIO, ODILA. Metformin release with pseudoboehmite. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 955-956.

    Abstract: Diabetes Mellitus is a chronic disease in which high levels of blood glucose are found. It arises when the pancreas does not produce enough insulin, a hormone that regulates blood sugar concentration. It also occurs when the body does not properly use the insulin it produces. There are two main forms of diabetes: type 1 diabetes, the treatment of which is insulin injections, and type 2 diabetes, where the body's cells do not respond to insulin properly. In Brazil the diseases that most affect the population are diabetes, hypertension and stroke. The number of Brazilians diagnosed with diabetes has grown 61.8% in the last 10 years. In 2006, 5.5% of the population had the disease and in 2016 8.9% [1]. It has also been observed in Brazil that diabetes increases with age and is almost three times higher among those with lower schooling. People between the ages of 18 and 24 have a rate of 0.9%, between 35 and 44 years old, the rate is 5.2%, and among people aged 55-64 years, the number reaches 19.6%. The largest registry, however, is in the population aged 65 years or older, which presents an index of 27.2%. In recent years, several papers reported the use of pseudoboehmite for use in controlled drug delivery systems. The drugs tested include atenolol [2], Glucantime® [3], acyclovir [4] and DOX, a typical chemotherapeutic anticancer drug [5]. In this research pseudoboehmite was produced by sol-gel process and metformin was incorporated in the gel of pseudoboehmite. After that the gel was vacuum filtered and dried to obtain a powder by freeze-drying. The dry powder was characterized by x-ray diffraction, thermal analysis (Thermogravimetric analysis and differential thermal analysis), nitrogen adsorption isotherm, specific surface area by B.E.T. method and scanning electron microscopy using secondary electron detector and EDS detector. The results shows that the drug was homogeneously incorporated in the pseudoboehmite.

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  • IPEN-DOC 26834

    ANDRADE, ARNALDO H.P. de ; LOBO, RAQUEL de M. ; BREDA, FRANCISCO J. ; CASTAGNET, MARIANO . Mechanical anisotropy of ABS specimens 3D printed by FDM. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 2564-2564.

    Abstract: Additive manufacturing (AM) has been developed as a technique for fast fabrication of component parts through 3D printing, using a process of adding successive layers, one after another. The Fused Deposition Modeling (FDM) technique is a 3D printing process that generally uses a thermoplastic filament as the printing base material. The material is fed by a coil and the head of the extruder performing the process is heated. Printing can be done in several directions, depending on the purpose of the component part. In this work mechanical tests were done on ABS (Acrylonitrile-Butadiene-Styrene) tensile specimens built by FDM, in different orientations, to analyze its properties and to make a correlation between these properties and the influence of the printing direction in the final product. The tensile specimens in dog bone shaped were tested according to the ASTM D638 standards. The experiments were done at room temperature. The horizontal built specimens (H-specimens), fabricated in the z-direction, while the beads were layered along the x and y direction, parallel to the build table, showed the maximum resistance of 30 MPa. The specimens built with their gage length out of x-y plane (V-specimen and D-specimen, vertical and diagonal specimens respectively) presented lower ultimate strength, for instance 14 MPa for the Vspecimen. Additional investigation is on the way to understand the presence of defects (cavities and crazes) in the ABS microstructure since the literature points that the ability to manipulate it is the key to an improved performance of this type of structural material.

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  • IPEN-DOC 26833

    LEAL NETO, RICARDO M. ; VEGA, LUIS E.R.; FALCÃO, RAILSON B. ; LEIVA, DANIEL R.; ROCHA, CLAUDIO J. ; ISHIKAWA, TOMAZ T.; KIMINAMI, CLAUDIO S.; BOTTA, WALTER J.. Mechanical activation of TiFe for hydrogen storage: ball milling x cold rolling. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 49-50.

    Abstract: The aim of this work is to report some recent developments on the synthesis of TiFe by high energy ball milling and cold rolling, concerning hydrogen storage. Ball-milled TiFe was produced by two procedures, both under inert atmosphere and with various milling times. In the first one a powder mixture of TiH2 an Fe was milled, followed by a vacuum heat treatment to promote the reaction synthesis of TiFe compound [1]. Second procedure consisted of milling Ti and Fe powders with stearic acid (as a process control agent) after a pre-milling operation (with the same powders and without PCA) to prepare the surface of milling media. Both methods were conceived for avoiding strong adherence of the powders to the milling balls and vial, impairing the mechanical alloying. Cold rolling was performed on a ground TiFe ingot produced by arc melting [2]. After 20 to 40 passes under inert atmosphere, powder particles and thin cracked flakes were produced. Results showed that both milling procedures succeeded in avoiding unacceptable adherence to the milling media, with high loose powder yields. Whatever the route, nanostructured TiFe was obtained with no need of further thermal activation for the first hydrogenation. Hydrogen absorption capacities of about 1.0 wt% at room temperature was obtained with both milling procedures. Higher capacity (1.4wt%) was obtained with cold rolled TiFe (powder and flakes) after 40 passes. Some possible explanations for this difference are presented and discussed.

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  • IPEN-DOC 26832

    PIERETTI, EURICO F. ; NEVES, MAURICIO M. das . Magnetic susceptibility of a laser treated biomaterial. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 2024-2024.

    Abstract: Austenitic stainless steel ISO 5832-1 is widely used as biomaterial due to its mechanical properties, chemical composition, degradation resistance and low cost. In this work, we evaluated the magnetic susceptibility of samples of this biomaterial, with laser texturing surface treatment in four different pulse frequencies, as well as samples without laser treatment, for comparison purposes. Relative magnetic permeability (μr) measurements were performed on a magnetic susceptibility scale. A Bruker magnetic force microscope (MFM), model SPM Multimode 8, with analysis processing software Nanoscope Analysis, was used in the Tapping Mode operation to perform naturally generated magnetic field measurements on the laser textured samples surfaces. The treatments affected the magnetic susceptibility of these surfaces, which was higher for the textured samples when compared to the other surface finishing conditions, which is undesirable for a biomaterial. The magnetic field evaluations by MFM are of qualitative character. Qualitatively distinct images of amplitude and phase difference signals were noted. This fact proved the results obtained by the technique of measurement of magnetic signals by precision scale. The analysis of the images obtained by MFM suggested that the parameters variation for laser texturing resulted in variation of intensities and distribution of magnetic field signals on this biomaterial’s surfaces.

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  • IPEN-DOC 26831

    BUGARIN, ALINE F.S. ; TERADA, MAYSA ; POLITANO, RODOLFO ; COSTA, ISOLDA . Investigation of the evolution and influence of hardening phases on the corrosive behavior of AA2198. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 2120-2120.

    Abstract: The Al-Li alloys are 2XXX series aluminum alloys and has been gaining space in the aeronautical applications. Adding 1% by weight of Li to aluminum, reducing by 3% at the final density and increasing by an average of 6% in the modulus of elasticity of the material. The characteristics and advantages presented by the Al- Li alloys, together with the growing interest of the aeronautical industry, have resulted in the interest in studying the relationship between the microstructure and its corrosion behavior. Alloy 2198 is a third generation of Al-Li alloys. Alloy elements such as Cu, Li and Mg promote the increase of the mechanical strength of the alloy by solid solution and the precipitation of phases T1 (Al2CuLi), Ɵ '(Al2Cu) or S (Al2LiMg). Phase T1 is the main hardening phase of the material and because it is more electrochemically active, it decreases the corrosion resistance. In this work, the AA2198 as received was solubilized at 500 °C to clear the thermal history of the material. A homogenization treatment was carried out for 1 h and 4 h with mechanical vacuum and an oven with argon controlled atmosphere. Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA) tests were performed to verify the kinetics and influence of phase precipitations on the mechanical response of the material. The resistance to corrosion of the different homogenization conditions was investigated with electrochemical tests, such as Open Circuit Potential (OCP) and Polarization.

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  • IPEN-DOC 26830

    SANTANA, JESSICA C.C. de C.; SILVA, REJANE M.P. da ; ANTUNES, R.A.; SANTOS, SYDNEY F.. Influence of decarburization on the local corrosion behavior of the SAE 9254 spring steel. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 2199-2199.

    Abstract: Decarburization is an unwanted metallurgical phenomenon comprising the loss of carbon from the steel through outward diffusion and oxidation on the surface at high temperatures. As this phenomenon leads to phase transformations in a small region close to the surface, it is likely expecting some effects on the local chemical reactivity of the steel. This, in turn, would account for the appearance of preferential anodic sites that can act as localized corrosion spots. Macroscopic corrosion symptoms, observed by conventional corrosion techniques, express only the final step of a complex and dynamic sequence that begins at the microscopic level. Several localized electrochemical techniques can be used to characterize local corrosion processes. One of them is the scanning electrochemical microscopy (SECM). The aim of the present work was to study the surface chemistry, microstructure and local corrosion processes at the decarburized layer of the SAE 9254 automotive spring steel. The samples were austenitized at 800, 850, 900 and 950 °C followed by oil quenching. The microstructure was investigated using confocal laser scanning microscopy and scanning electron microscopy. The surface chemistry was analyzed by X-ray photoelectron spectroscopy. The local electrochemical activity was probed by SECM. Microstructural characterization and XPS analysis indicate a dependence of the local electrochemical processes with the steel microconstituents and also Si and Cr oxides formed during heat treatments. The presence of the ferritic layer enhanced the multiphase character of the steel microstructure in the region of partial decarburization of sample A900, increasing iron oxidation and, therefore, the local electrochemical activity for this condition.

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  • IPEN-DOC 26829

    LOBO, RAQUEL de M. ; MORCELLI, APARECIDO E.; BREDA, FRANCISCO J. ; CASTAGNET, MARIANO ; ANDRADE, ARNALDO H.P. de . Fracture surface analysis of ABS samples printed by the FDM method. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 2567-2567.

    Abstract: FDM (Fused Deposition Modeling) is one of the most used technique in additive manufacturing (AM). It can be summarized as printing small components through a heated thermoplastic filament, which is deposited layer by layer through a 3D printer. The print head can be programmed to perform the job in different directions (X, Y and Z) even with predetermined slopes. In this work, flat tensile specimens were prepared in different directions using an ABS (Acrylonitrile-Butadiene-Styrene) filament with a processing temperature between 210-225 ° C. After tensile tests, the fracture surfaces were analyzed to get a better understanding of the deformation and fracture processes. The crosssection view of specimen´s morphology was examined with a scanning electron microscope at a very low accelerating voltage (1 kV). The specimens were coated with gold using a sputtering system. The specimens that showed the smaller ultimate strength (named V-specimen) presented numerous large cavities in its microstructure suggesting that these voids may have a major contribution to the mechanical performance of the material.The fracture surface also shows a possible pull-out between layers indicating a weak point in the microstructure of the built sample that’s requires further investigation.

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  • IPEN-DOC 26828

    RAMANATHAN, LALGUDI V. ; FERNANDES, STELA M.C. ; CORREA, OLANDIR V. . Effect of mixed nanocrystalline rare earth oxide coatings on high temperature oxidation of a ferritic stainless steel AISI 409. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 414-414.

    Abstract: Rare earths (RE) have been used to improve the high temperature oxidation resistance of chromium dioxide and alumina forming alloys. The RE can be added to the alloy as elements or as oxide to form dispersions. It can also be applied as a RE oxide coating on the surface of the alloy. In this investigation the sol-gel technique was used to prepare sols of the RE oxides as it produces nanocrystalline oxide particles. In an effort to increase further the oxidation resistance of high temperature alloys, optimization of RE oxide additions to the alloy surface was attempted. This paper presents the effect of nanocrystalline oxide gel coatings of CeO2, Nd2O3, Pr2O3, CeO2 + Nd2O3, CeO2 + Pr2O3 and Pr2O3 + Nd2O3 on the oxidation behavior of a ferritic stainless steel AISI 409 at 1000 °C in air using a thermogravimetric balance. The morphology of the pure oxides was studied and the following formats were observed: CeO2 – rods; Nd2O3 – platelets; Pr2O3 – needles; La2O3 – cuboids. The average oxide particle sizes and the average crystallite sizes were also determined. The oxidation rate of the coated steel specimen was significantly less than that of the uncoated steel specimen, due to formation of a fine layer of chromium dioxide at the steel/oxide interface. The oxidation rates of the different REO coated steel specimens varied with the type of REO. The mixed oxide containing Pr2O3 increased significantly the oxidation resistance of the steel. The CeO2 + Nd2O3 mixture did not increase oxidation resistance of the steel further, compared to those with either one of these two rare earth oxides. The differences in the influence of a specific rare earth oxide or a mixture are attributable to differences in the ionic radii of the RE and the morphology as well as the crystallite sizes of the RE oxides.

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  • IPEN-DOC 26827

    AGUIAR, DEIZE B. dos S.; QUEIROZ, FERNANDA M.; VERISSIMO, NATHALIA C.; AYUSSO, VICTOR H. ; PEREIRA, VICTOR F.; FONSECA, EDUARDO B. da; MELO, HERCILIO G. de; COSTA, ISOLDA ; TERADA, MAYSA ; BUGARIN, ALINE F.S. . Effect of Ce on the corrosion resistance of anodized AA2024-T3 FSWed. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 2111-2112.

    Abstract: Friction stir welding (FSW) is a solid-state joining technique, which has numerous advantages over conventional fusion techniques, such as automation and reproducibility, environmentally friendly, and capability to weld large thicknesses in a single pass. AA2024 are widely used in the aerospace industry due to their properties as lightweight, high specific strength and durability. However, they are prone to localized corrosion due to its high amount of intermetallics. New anodizing and sealing processes have been studied due to the environmental and health problems related to the sealing treatment containing hexavalent chromium ions. This has encouraged the search for new processes for surface treatment of metals. Recent studies are pointing towards tartaric-sulphuric anodizing, as a viable alternative for the corrosion protection of aluminum alloys, including surface treatments with cerium ions. Other promising method to protect the exposed metal surface is to use eco-friendly alternative corrosion inhibitors in combination with a barrier coating system. Sol–gel coatings have also been extensively studied as potential pre-treatments not associated to toxic residues for aluminum alloys surface preparation prior to paint. It has been demonstrated an efficient alternative for replacement of the chromate technology. In this study, friction stir welded samples were anodized and then sealed in an aqueous solution with the addition of cerium ions at 70 °C. The effect of Ce on the characteristics of the surface film formed, such as morphology and corrosion resistance, was investigated by SEM and electrochemical impedance spectroscopy. Samples unsealed or hydrothermally sealed were also tested for comparison. The EIS results showed that the addition of Ce (III) ions improved the corrosion resistance of the AA 2024-T3 TSA anodized and hydrothermal sealed.

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  • IPEN-DOC 26826

    GIAROLA, JOSEANE M.; PEREIRA, GUALTER S.; KUGELMEIER, CRISTIE L.; TERADA, MAYSA ; MARCOMINI, JOSE B.; ROVERE, CARLOS A.D.; AVILA, JULIAN A.; BOSE FILHO, WALDEK W.. Corrosion behavior of friction stir welded API X70 steel joints. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 2171-2171.

    Abstract: The ever-increasing demand for fossil fuels has pushed the oil and gas industry to search for new deep water wells and in more aggressive environmental conditions, such as the pre salt where the presence of CO2 and H2S concentrations, has led to the development of new materials and manufacturing processes. For pipeline construction, Friction Stir Welding (FSW) process is a promising candidate to be used in the girth welding procedure, and research studies must be carried out to understand the effect of this new processing on the pipeline life under the in-service conditions (environment, fatigue). The present work is part of a research project aiming to investigate the effect of a saline environment on the mechanical properties of an API-5L-X70 steel, welded by FSW. Therefore, in this work, the results of the corrosion behavior analysis carried out on the FSW welded joint, considering a 3.5% NaCl solution, are presented. The corrosion behavior was investigated based on potentiodynamic polarization tests on the different regions of FSW welded joint, i.e., the base metal (BM) and stirred zone (SZ). Gel visualization tests, considering the whole welded joint, were also conducted. The two FSW regions showed similar polarization curves in terms of corrosion potential (Ecorr), corrosion current density (icorr) as well as anodic current density values. In the gel tests, a preferential localized attack on any of the regions of the FSW welded joint was not observed. These results can be interpreted as evidence that the corrosion behavior of the FSW welded joint was not significantly affected by the different metallurgical microstructures formed by the FSW processing.

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  • IPEN-DOC 26561

    SONA FILHO, CELSO R. ; BENTO, RODRIGO T. ; SILVA, CECILIA C.G. e ; PILLIS, MARINA F. . Physical-chemical characterization of Si3N4-TiO2 ceramic nanocomposites obtained to biomedical applications. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 1051-1051.

    Abstract: Silicon nitride based ceramics (Si3N4) are very important materials in the engineering and medical fields because of their physical, chemical, tribological and mechanical properties. However, some researchs have been carried out in order to obtain silicon nitride ceramics with improved biological behavior, including studies about the effect of nanoparticles on their bioactivity. In this work, Si3N4-TiO2 nanocomposites were synthesized and characterized by their physical, chemical and bioactive properties. Initially, Si3N4, MgO, SiO2 and CaO powders were mixed in a ball mill for 24 h The mixture was then dried at 100 ºC for 1 h under the nitrogen atmosphere. Subsequently, the samples were coated with TiO2 from the sol-gel process. The precursor solution of titanium dioxide (TiO2 ) was prepared from the mixture of titanium (IV) isopropoxide and isopropanol at a ration of 1:10. The pH of the solution was adjusted to 3 by the addition of sulfuric acid. The precursor solution was dispersed by constant stirring at 50 ºC for 1 h. The samples were immersed for 10 minutes in this solution at room temperature and then dried for 24h under UV light. The samples were calcined at 400 and 500 ºC for 60 min to obtain Si3N4-TiO2 nanocomposites. The microstructure of the materials were anayzed by scanning electron microscopy, atomic force microscopy, and X-ray diffraction. The samples bioactivity was evaluated by in vitro tests using SBF (Simulated Body Fluid) solution at 37 ºC for 9 days of immersion. The nanocomposites showed good quality, high uniformit of coating and greater adhesion to TiO2 to the substrate of Si3N4. The formation of CaP deposits with globular structure on the samples surface during the SBF experiment is a strong indication of the bioactivity of the nanocomposites. The results suggest that Si3N4-TiO2 ceramic nanocomposites have great potential to be used in biomedical applications.

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  • IPEN-DOC 26554

    NERY, JOSE G.; RATERO, DAVI R.; SILVA, DANILO A. da; MARUMO, JULIO T. ; ARAUJO, LEANDRO G. de ; MEDEIROS, VINICIUS L.. Hydrothermal and assisted microwaved syntheses of Stanno and Yttrium metallosilicates as heterogeneous catalyst for biodiesel production and environmental remediation. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 484-484.

    Abstract: This study reports the synthesis, physicochemical characterization by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and solid-state MAS NMR (1H, 23Na, 29Si and 89Y and 119Sn MAS NMR) of a stanno and yttrium metallosilicate and their application as a heterogeneous catalyst for biodiesel production via ethanolysis and methanolysis routes using edible, non-edible an waste oils as feedstocks and environmental remediation. Heterogenous catalytic studies in the transesterification of refined edible, non-edible, and waste oils have resulted in high yields of FAMEs and FAEEs (fatty acid methyl and ethyl esters), nevertheless the highest FAMES (98.2%) and FAEEs (96.6%) yields were obtained for non-edible microalgae oil extracted from the genetically modified heterotrophic algal strain Prototheca moriformis. Catalytic studies also using nonedible macaw palm oil (Acrocomia aculeata) with a high content of free fatty acids (FFAs) demonstrated that the catalyst could simultaneously perform esterification and transesterification reactions using using different sources of lipids feedstocks, notably those that do not compete with food production [1]. On the other hand, Yttrium metallosilicate were very efficient in the separation, binding and chemical stabilization of hazardous inorganic, organic and radioactive species such as lead ( Pb2+, Cd2+, Ba2+ , Cs+ and Sr2+) in aqueous systems.

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  • IPEN-DOC 26543

    SANTOS, EMANUELLA C. dos; BATISTA, BEATRIZ da S.; LIMA, RUANA C.; ALENCAR, LUCIANA M.R.; SANTOS, ADENILSON O. dos; PEDROCHI, FRANCIANA; OTUBO, LARISSA ; LANG, ROSSANO; SILVA, LUZELI M. da. Bioactivity study of Co-Cr alloys doped with tantalum for biomedical applications. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 1017-1018.

    Abstract: Co-Cr alloys are well known because of its high wear resistance, mechanical strength and corrosion resistance due to the chromium oxide passive layer formation that protects the material surface [1].The addition of alloying elements, particularly Mo and W, improve the properties of Co-Cr bioalloys, although these materials can still be improved to meet the requirements for a biomaterial.Thus, considering that tantalum is a bioactive metal, it can be an interesting option to improve the biocompatibility properties of these alloys[2].The present study aims the synthesis and in vitro evaluation bioactivity of Co-Cr alloy doped with tantalum.The synthetized alloys were submitted to a surface treatment and subsequentlyimmersed in Simulated Body Fluid (SBF) for 28 days. The samples bioactivity was evaluated by using X- ray Diffraction (DRX), Scanning Electron Microscopy (SEM), Dispersive Energy Spectroscopy (EDS) and Atomic Force Microscopy (AFM) techniques. X- ray diffraction analysisin the SBF immersed samples shown a small intensity peak characteristicof hydroxyapatite while MEV and EDS results revealeda surface structure with the presence of P, Mg, Ca and Oelements. The grain growth dynamics on the samples surfaces was observed by using AFM measurements.

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  • IPEN-DOC 26533

    BORAZANIAN, TATYANA C.F. ; CORREA, OLANDIR V. ; BENTO, RODRIGO T. ; PILLIS, MARINA F. . Influence of the heat treatment on the photodegradation efficiency of the supported TiO2 catalysts obtained by a facile airbrush spray-coating. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 1665-1666.

    Abstract: One of the main topics of thin films processing routes based on sol-gel is the need for low-cost and simple techniques [1]. Airbrush spray-coating method has been applied to coat materials, due to its cost-effective, large area and versatile characteristics [2]. However, this technique is not yet sufficiently explored for supported catalysts employed on the water treatment. In this work, titanium dioxide (TiO2) films were successfully deposited on borosilicate substrates by a facile airbrush spray-coating technique, at room temperature, from a solution of titanium (IV) isopropoxide diluted in isopropanol. The angle of the cold spray was fixed in 45°, and the feed rate was 17 mm.s-1. The coated specimens were dried at 100 °C for 60 min, and then heat treated at 300, 450 and 500 °C for 30 min to evaluate the influence of the temperature process on the methyl orange dye degradation under UV light. The catalysts obtained showed a great surface covering, highly porous surface, and good adherence to substrate. The films presented the formation of TiO2-anatase phase. Methyl orange dye degradation experimental results indicated that the TiO2 film heat treated at 500 °C presented a higher photocatalytic behavior, that exhibited 68.3 % of the dye degradation for 300 minutes under UV radiation – around 18.5 % more efficient than the supported catalysts prepared at 300 and 450 °C, with a photocatalytic efficiency of 31.6 % and 57.7 %, respectively. The study of the influence of heat treatment on the photocatalytic activity suggests the existence of an ideal temperature in which the photocatalyst exhibits the better photodegradation performance. The results suggest that the supported TiO2 catalysts deposited by the airbrush spraycoating method have a promising practical application for the green treatment of organic pollutants.

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  • IPEN-DOC 26532

    MARCELLO, BIANCA A. ; CORREA, OLANDIR V. ; BENTO, RODRIGO T. ; PILLIS, MARINA F. . Effect of the thickness of TiO2 films on the photodegration of methyl orange dye. In: BRAZIL MRS MEETING, 18th, September 22-26, 2019, Balneário Camburiú, SC. Abstract... São Carlos, SP: Aptor Software, 2019. p. 1696-1696.

    Abstract: The increase of the disposed of azo dyes such as methyl orange (MO) by textile and allied industries in the wastewater results in a significant increase of pollutants, which requires the development of new degradation materials and techniques to purify the effluents [1]. Heterogeneous photocatalysis using titanium dioxide (TiO2) films is a highly efficient oxidative process for water treatment [2]. The TiO2 films were grown on borosilicate substrates by metalorganic chemical vapor deposition (MOCVD) at 500°C, and the growth time was controlled in order to obtain films with the thickness of 400, 600 1100 and 2100 nm. MO dye degradation was evaluated by using anatase-TiO2 as photocatalyst under UV light. The pH of the solutions was set on 2. The TiO2 films presented uniform thickness and well-defined columnar structure that grow perpendicular to the substrate surface. The increasing of the growth time increases both the thickness and the mean grain size of the films. All the films presented the formation of anatase-TiO2 crystalline phase grown preferentially oriented at (112). The results showed that the photocatalytic behavior of the films decreased with increasing the film thickness. The photocatalytic efficiency for the 400, 600, 1100 and 2100 nm films tested at pH 2 are respectively 39.2%, 30.2 %, 24.4 % and 12.2 %. When the thickness of the films augments, the mobility of the electrons is impaired due to the increase of the film opacity, which limits the light penetration through the catalyst, and difficults the diffusion of charge carriers required to activate the semiconductor surface. TiO2 catalysts grown by MOCVD technique is a practical promising application for the water treatment.

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  • IPEN-DOC 26825

    COUTO, CAMILA P. ; REVILLA, REYNIER; COSTA, ISOLDA ; PANOSSIAN, ZEHBOUR; ROSSI, JESUALDO ; TERRYN, HERMAN; DE GRAEVE, IRIS. Investigation of electrochemical behaviour of 22MnB5 steel coated with hot-dip Al-Si before and after hot stamping process by means of SKPFM measurements. In: EUROPEAN CORROSION CONGRESS, September 9-13, 2019, Seville, Spain. Abstract... 2019.

    Abstract: The demand for hot stamped components has been growing in structural vehicle applications, due to the advantages of combining lightweight design and safety improvement. Boron-manganese 22MnB5 steel is the most common grade for hot stamping applications. After the thermomechanical process, the steel exhibits up to 1,500 MPa of tensile strength with the absence of the springback effect. The hot stamping process involves heating the steel blank to the austenitization temperature and then transferring it from the furnace to the press tool, where the material is formed and quenched simultaneously. Due to high temperatures during the process, the steel blank is protected with a metallic coating to avoid the steel decarburization and oxidation. Hot-dip Al-Si is the most applied coating system on boron-manganese steel for hot stamping applications. It is known that, during hot stamping, diffusion takes place changing the coating layer morphology. The objective of this study is to investigate the effect of the hot stamping process on the electrochemical behaviour of 22MnB5 steel coated with hot-dip Al-Si by means of the SKPFM technique. Moreover, the samples were characterized by means of FE-SEM/EDS. The SKPFM results showed that, before the hot stamping process, there is a high difference of potential between the coating layer and the steel substrate. After hot stamping, this difference decreases. In both conditions (before and after hot stamping), the coating layer is less noble than the steel substrate. It was also observed that the steel substrate potential also decreased after the hot stamping process. This could be a consequence of iron diffusion towards the coating layer and the recrystallization of the substrate after the thermo-mechanical process.

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  • IPEN-DOC 26824

    SILVA, REJANE ; MILAGRE, MARIANA ; OLIVEIRA, LEANDRO; ANTUNES, RENATO; DONATUS, UYIME ; COSTA, ISOLDA . Influence of surface finishing on the electrochemical activity of the 2098-T351 aluminum alloy. In: EUROPEAN CORROSION CONGRESS, September 9-13, 2019, Seville, Spain. Abstract... 2019.

    Abstract: In this work, scanning electrochemical microscopy (SECM) measurements were employed to characterize the electrochemical activities of polished and as-received surfaces of the 2098-T351 aluminum alloy (AA2098-T351). The effects of the near surface deformed layer (NSDL) and its removal by polishing on the electrochemical activities of the alloy surface were evaluated and compared by the use of different modes of SECM. Confocal Laser Scanning Microscopy (CLSM) and energy dispersive X-ray spectroscopy (EDS) were also employed to characterize the morphology of the surfaces. The surface chemistry was analyzed by X-ray Photoelectron Spectroscopy (XPS). The generation/tip collection (SG/TC) and competition modes of the SECM were used to study hydrogen gas (H2) evolution and oxygen reduction reactions, respectively. H2 evolution and oxygen reduction were more pronounced on the polished surface compared to the asreceived surface that revealed lower electrochemical activities showing that either the NSDL largely decreased the local electrochemical activities at the AA2098-T351 surface.

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  • IPEN-DOC 26823

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

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

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  • IPEN-DOC 26822

    CORREA, B.S.; COSTA, M.S.; CABRERA-PASCA, G.; SENA, C.; PINTO, R.H.; CARVALHO JUNIOR, R.N.; FREITAS, R.S.; SAIKI, M. ; CORREA, E. ; CARBONARI, A.W. . Can natural oils improve the properties of magnetic nanoparticles?: A systematic study of iron oxide nanoparticles coated with oils from Amazon fruits. In: ANNUAL CONFERENCE ON MAGNETISM AND MAGNETIC MATERIALS, 64th, November 4-8, 2019, Las Vegas, Nevada, USA. Abstract... 2019.

    Abstract: The use of nanoparticles coated with different materials have been studied by many researchers to improve the quality of nanomaterials for biomedical applications such as controlled drug delivery, image contrast and treatment of cancer by magnetic hyperthermia [1]. In this work, we used oils extracted from ucuúba (Virola surinamensis), bacaba (Oenocarpus bacaba Mart.) and açaí (Euterpe oleracea Mart.) to coat Fe3O4 nanoparticles. The ucuúba, bacaba and açaí are native trees of the Amazon forest, whose oils are rich in fatty acids, such as lauric, myristic, steatic, oleic, palmitic, and linoleic acid, with different proportions. These pure oils, free of solvents, were obtained by the extraction method with carbon dioxide in the supercritical state [2], and then added during the synthesis process of iron oxide nanoparticles by thermal decomposition method [3]. The results of X-ray diffraction confirmed the formation of Fe3O4 single phase. The average size around 3 nm and spherical morphology of the magnetite nanoparticles was determined by transmission electron microscopy. The study of magnetic properties revealed a saturation magnetization (Ms) enhancement and high values of the anisotropy constant for Fe3O4 samples when coated with açaí (91.4 emu.g-1; 4.6 105 J.m-3) and ucuúba (80.6 emu.g-1; 9.3 105 J.m-3) oils, which present a large percentage of saturated total fatty acid. The results indicate that nanoparticles with sizes smaller than around 5 nm present Ms values as high as those found in bulk Fe3O4 and higher than those usually obtained for nanoparticles coated with oleic acid [4]. The neutron activation analysis (NAA) nuclear technique was used to determine with high accuracy the mass of Fe in the Fe3O4 core of nanoparticles in order to normalize the magnetization values [5]. These results show that natural oils have a great potential to produce stable and quality nanoparticles as compared with conventional coated.

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  • IPEN-DOC 26821

    NOGUEIRA, A.L.; MUNITA, C.S. ; COSTA, A.F.; GOMES, D.M.C.; KIPNIS, R.. Quantitative methods of standardization in cluster analysis: finding groups in data. In: ACHARYA, R. (Ed.); SWAIN, K.K. (Ed.); SATHYAPRIYA, R.S. (Ed.); REDDY, A.V.R. (Ed.); PUJARI, P.K. (Ed.) INTERNATIONAL CONFERENCE ON MODERN TRENDS IN ACTIVATION ANALYSIS, 15th, November 17-22, 2019, Mumbai, India. Abstract... Mumbai, India: Bhabha Atomic Research Centre, 2019. p. 76-76.

    Abstract: The archaeological study of ceramics using multi-elemental analytical techniques such as instrumental neutron activation analysis (INAA) is important in archaeology due to its potential to identify the raw materials used in their manufacture,and subsequently help to infer the degree of interaction among ancient communities. Several multivariate statistical methods are used in chemical composition data analysis, such as principal component analysis, cluster analysis and discriminant analysis. Pattern recognition approaches are divided into unsupervised learning and supervised learning. Cluster analysis is a technique for pattern recognition and is an unsupervised approach. When applying cluster analysis, raw data, or actual measurements, are not used directly. Thus, a problem that arises during cluster analysis involves the decision of whether or not to standardize the input variables before calculating measures of distance. The standardizationof variables is necessary in cases where the measure of dissimilarity, such as the Euclidean distance, is sensitive to differences in the magnitudes or scales of the input variables. The aim of this paper is to assess the impact, and evaluate the usefulness of three standardization techniques in determining the number of clusters for a data set of 140 ceramic fragments from eight archaeological sites from the upper Madeira river, Rondônia, Brazil, in which Na, K, La, Sm, Yb, Lu, Sc, Cr, Fe, Co, Zn, Rb, Cs, Ce, Eu,Hf, Ta, and Th mass fractions were determined by INAA.

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  • IPEN-DOC 26820

    SANTOS, U.P.M. ; LOURENÇO, F.R.; MOREIRA, E.G. . Experimental design and z-score results are useful tools for optimizing Instrumental Neutron Activation Analysis procedures. In: ACHARYA, R. (Ed.); SWAIN, K.K. (Ed.); SATHYAPRIYA, R.S. (Ed.); REDDY, A.V.R. (Ed.); PUJARI, P.K. (Ed.) INTERNATIONAL CONFERENCE ON MODERN TRENDS IN ACTIVATION ANALYSIS, 15th, November 17-22, 2019, Mumbai, India. Abstract... Mumbai, India: Bhabha Atomic Research Centre, 2019. p. 133-133.

    Abstract: In this study the optimization of procedures of an Instrumental Neutron Activation Analysis (INAA) method were carried out for the determination of the elements bromine, chlorine, magnesium, manganese, potassium, sodium and vanadium in biological matrix materials using irradiations up to 60 s at a pneumatic station. 2k experimental designs were applied for assessment of the individual influence of selected variables of the analytical procedure in the mass fraction results. The chosen experimental designs were the 23 and the 24, depending on radionuclide half-lives. Different certified reference materials and multi-element comparators were analyzed, considering the following variables: irradiation time, sample decay time, sample distance to detector and counting time. Gamma ray spectrometer, comparator concentration, and sample mass were maintained constant in this study. By means of statistical analysis experimental considerations, optimized experimental conditions for the analytical methodwere determined and will be adopted for the validation procedure of INAA methods at the Research Reactor Center of the Nuclear and Energy Research Institute (IPEN – CNEN/SP). Optimized irradiation and measurement conditions were established based on experimental design resultsusing the obtained z-scores for the various elements and experimental conditions.

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  • IPEN-DOC 26819

    SILVA, S.A.; JUNQUEIRA, L.S. ; FRANKLIN, R.L.; SILVA, W.L.; FAVARO, D.I.T. ; MOREIRA, E.G. . Sedimentary profiles from a water supply reservoir at São Paulo, Brazil: trace and rare earth elements assessment by INAA. In: ACHARYA, R. (Ed.); SWAIN, K.K. (Ed.); SATHYAPRIYA, R.S. (Ed.); REDDY, A.V.R. (Ed.); PUJARI, P.K. (Ed.) INTERNATIONAL CONFERENCE ON MODERN TRENDS IN ACTIVATION ANALYSIS, 15th, November 17-22, 2019, Mumbai, India. Abstract... Mumbai, India: Bhabha Atomic Research Centre, 2019. p. 79-79.

    Abstract: A research project has been conducted by the Environmental Company of São Paulo State (CETESB) and the Nuclear and Energy Research Institute (IPEN) in important water supply reservoirs at São Paulo State in order to perform a wide evaluation on the content of rare earths and some trace elements in sediment profiles. In the present study, preliminary results for two sampling campaigns at the Graminha reservoir are presented:February/2015 (sites 1 and 3) and August / 2015 (sites 1 and 2). Sediment core samples (around 90 cm long) were collected in the dam and sliced at every 2.5 cm. Instrumental Neutron Activation Analysis (INAA) was applied to the sediment samples in order to determine some trace elements (As, Cr, Th, U and Zn) and rare earth elements (REE) (Ce, Eu, La, Lu, Nd, Sm, Tb and Yb). The analytical methodology validation was performed by means of certified reference material analyses. As, Cr and Zn concentration values were compared to the oriented values from CCME (Canada) (TEL and PEL). Sediment quality was classified as good or very good for these elements according these criteria. Enrichment factor (EF) and Geoaccumulation Index (IGeo index)1were applied to the results by using the concentration values of the last layer of the 90.0 cm profile as background values for sediment contamination index assessment. EF>1.5 was found for REE, U and Th in the middle of the sediment profiles,in all sampling points, indicative of anthropogenic contribution. IGeo values in the range of1<IGeo<5 were found, being the sediments classified as moderate to very polluted for these elements. The normalization of REE concentrations with respect to a geological reference value, a useful tool to obtain a comparison among information from contamination sources2 was used in the present study by using NASC (North American Shale Composite) and PAAS (Post Archean Australian Shale) normalization as reference values. In addition, La/Sm, La/Yb and Sm/Yb ratios were calculated and discussed.The present study data are intended to start a sediment REE concentration data bank in water supply reservoirs and maybe they can be used in the future to establish legal limits for CETESB.

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  • IPEN-DOC 26818

    ARAUJO, S.G. ; LANDINI, L. ; ZEFERINO, G.R.; SALVADOR, V.; SCAPIN, M.A. . Resíduos de frutos do mar: oportunidades potenciais para produção de materiais bioativos. In: WORKSHOP DE ÓRGÃOS ARTIFICIAIS, BIOMATERIAIS E ENGENHARIA DE TECIDOS, 6., 29-31 de outubro, 2019, São Paulo, SP. Resumo... Belo Horizonte, MG: Sociedade Latino Americana de Biomateriais, Órgãos Artificiais e Engenharia de Tecidos, 2019.

    Abstract: Resíduos de frutos do mar: oportunidades potenciais para produção de materiais bioativos Resíduos de frutos do mar são fontes ricas em diversos compostos e materiais bioativos e anualmente, no mundo, milhões de toneladas destes resíduos (conchas, ostras, camarões, caranguejos, lagostas, mariscos, etc) são produzidos. No Brasil, cerca de 2 milhões de toneladas somente no Litoral Sul/SP. Com este problema ambiental, há grande geração de resíduos sólidos de atividades pesqueiras e/ou de maricultura,frequentemente despejados em terrenos baldios, aterros sanitários ou no mar. No entanto, eles embutem grande quantidade de elementos/compostos químicos valiosos (cálcio, quintina, pigmentos, proteínas), e poderiam ser usados para diversas aplicações na medicina, industrias farmacêuticas, alimentícias, energéticas, etc., Estes resíduos normalmente têm seus valores potenciais ignorados e o seu aproveitamento diminuiria a agressão ambiental e geraria renda aos maricultores e pescadores Neste trabalho, resíduos de frutos do mar foram calcinados para converter CaCO3 em CaO, sendo um dos catalisadores sólidos heterogêneos, altamente ativo, mais utilizados em reação de transesterificação de óleos vegetais para produção do biodiesel. Eles foram calcinados a 1000°C e usados em pó (100 a 200mesh). A caracterização antes e após calcinação foi por WDXRF (FRX por dispersão de comprimento de onda),. O teor de Ca era de 36,2% e de 98,8% de CaO, respectivamente. As propriedades catalíticas foram verificadas em testes de produção de biodiesel, em uma unidade reacional com micro-ondas do IPEN. O maior teor de éster metílico, em GC, obtido foi de 98%, em um teste de 11g de catalisador (P-300W; t-1h; T-65°C; 600rpm). As densidades ficaram dentro das especificações (850 a 900kg/m3) - 20°C. Com estes estudos, verificou-se que é possível aproveitar diversos tipos de materiais, empregando metodologias alternativas e mais conscientes, para proteção do meio ambiente.

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  • IPEN-DOC 26817

    FEDERICO, CLAUDIO A.; GONÇALEZ, ODAIR L.; PAZIANOTTO, MAURICIO T.; DIAS, ARTHUR F.; PRADO, ADRIANE C.M.; CALDAS, LINDA V.E. . A statistical evaluation on the cosmic radiation doses on aircrews flying over South America and Caribbean regions. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction There are substantial researches on the cosmic radiation doses received by aircrew on their typical fl ight workload. Most part of these studies was made by measurements onboard aircrafts of some specifi c companies in stablished routes. A recurrent question from countries over South America and Caribbean regions is related on the signifi cance of doses accumulated by aircrews over this region and if those magnitude justifi es a specifi c radiation protection procedure. Methods The evaluation was made by statistical analysis using CARI-6 aircrew radiation dose code and the data are derived from comprehensive records of registered fl ights performed in the South America and Caribbean airspace between 29,000 and 41,000 feet, performed from March 7 to 20, 2009. The analysis of this sample was composed of 80,548 route calculations totalizing 53,163 hours of real fl ights, by means of calculation of each track performed by aircrafts between aeronautic navigation waypoints. Results The analysis identifi es that the typical group of fl ight crew operating over this region receives mean dose rates ranging from 2.65 μSv/h to 2.95 μSv/h depending on the solar cycle. This distribution, integrated over typical workload from Brazilian aircrews results on annual doses ranging from 1.45 mSv to 1.67 mSv. Conclusions The results demonstrate that the typical aircrew fl ying over this region exceeds the annual radiation limit for public (1 mSv). The statistical analysis also shows that this is the case of more than 96% of the aircrew fl ying with this fl ight routine and workload. The presented results can be used by local authorities of countries over this region as a basis to evaluate the convenience on adoption the recommendation from ICRP Publication 132 regarding radiation protection recommendations for aircrews.

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  • IPEN-DOC 26816

    OLIVEIRA, LUCAS N. de ; NASCIMENTO, ERIBERTO O.; ANDREETA, MARCELLO R.B.; YAMAGUSHI, YASMIM Y.; JIUSTI, JEANINI; ANTONIO, PATRICIA L. ; CALDAS, LINDA V.E. . Evaluation of the FTIR technique for the linearity assessment of commercial soda-lime glass irradiated with gamma radiation. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction High dose dosimetry is one of the most important branches of everyday activities related to medical and industrial applications. Nevertheless, the use of materials that respond in a linear manner has advantages over nonlinear materials, since the dose calculation procedure in linear materials relies solely upon direct proportions to the delivered dose. The evaluation techniques are also important to identify the possible linear ranges, and the new Fourier-transform infrared spectroscopy (FTIR) technique has been used to this objective. This work aims to investigate the linearity response and its sensitivity, using mainly the FTIR technique. Methods Cubic samples of a soda-lime glass type with composition of Li2O.2B2O3 + 10 mol% of (0.25Li2O + 0.25La2O3 + TiO2) were irradiated with doses from 1 kGy to 12 kGy, using a 60Co Gamma-Cell system 220. The response was evaluated using the FTIR technique. Results The sensitivity and linearity characteristics were evaluated with the absorbed profi les of the multivariate calibration Partial Least Square Regression (PLSR), with its loadings performing a linear regression; from the slope value, the sensitivity of the glass at the absorbed dose range was obtained. The PLSR technique showed, on the range of 1-12 kGy, that the soda-lime glass type presents linearity value of 0.8532 using just three components. The results of the linearity test were obtained for the FTIR technique. Conclusions The FTIR technique was applied to assess the linear behavior based of the glass spectrum, showing its usefulness to identify possible linear dose regions and also the overall sensitivity of the glass samples to dose. Therefore, the results obtained indicate a good linear response, showing therefore a potential use of this glass-soda lime type for radiation dosimetry in high doses.

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  • IPEN-DOC 26815

    PRADO, EDUARDO S.P. ; GONÇALVES, MAX F.S.; MIRANDA, FELIPE de S.; PETRACONI FILHO, GILBERTO; MASSI, MARCOS; POTIENS JUNIOR, ADEMAR J. . Plasma reactor to viabilize the volumetric reduction of radioactive wastes. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction According of the International Atomic Energy Agency – IAEA, nuclear waste, also known as, radioactive waste, is any material containing a higher concentration of radionuclides than those considered safe by the national authorities. In Brazil, there is a National Nuclear Energy Commission to regulate. These wastes can be generated in nuclear power plants, industries, hospitals and research institutes. To permanently dispose of these radioactive wastes of low and medium level of radioactivity safely and cost effectively, these should be transformed into the physical and chemical compounds suitable for radionuclides immobilization with maximum volume and exhaust gaseous reduction. Incineration is used as a treatment for a very wide range of wastes. Incineration itself is commonly only one part of a complex waste treatment system that altogether, provides for the overall management of the broad range of wastes that arise in society. The objective of waste incineration, in common with most waste treatments, is to treat waste so as to reduce its volume and hazard, whilst capturing (and thus concentrating) or destroying potentially harmful substances. The incineration of waste is one of the most widespread and effective technologies allowing considerably to reduce waste volume. In this scope, among the promising technologies for the radioactive waste treatment is the plasma technology that allows reducing substantially the waste volume after exposing them to temperatures above 2500ºC. In the planning and management of radioactive waste, the challenges related to plasma technology are presented as a motivation factor for the possible implantation of plasma reactors in nuclear plants and research centers with the objective of improving the process of radioactive waste treatment. In this way, this work aims to evaluate the use of plasma technology for the incineration of radioactive waste for volumetric reduction and immobilization of this waste. Methods In this work, a plasma reactor was used for waste incineration, and all reactor parameters (electric energy ranges, maximum arc current, maximum working voltage, air fl ow, maximum energy conversion effi ciency, average temperature of heated gas, heated enthalpy) was controlled based on literature. The experiment was carried out in the plasma reactor (laboratory scale) of LPP in the ITA, using plasma torch transferred arc and with gaseous argon oxidizing agent. The electrical and thermal characteristics of the auxiliary systems of the plasma reactor were obtained using transducers and thermocouples. The composition of the gases in the process was analyzed using mass spectrometer and spectrophotometer. Results The accuracy of the data was important to ensure good results in the process, which allowed the extraction of relevant information from the experiments performed. The volumetric reduction reached 92% in relation to the sample before being processed, with a peak temperature of 1800ºC. Although a larger amount of argon fl ow intensify the cooling of the inner wall of the reactor, and further promote the dilution of the plasma, the arc voltage increases, resulting in higher power operation. Conclusions In the present work a high effi ciency thermal transfer torch was characterized , able to validate the use of the plasma jet for the treatment of radioactive waste.

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  • IPEN-DOC 26814

    MATSUSHIMA, L.C.; VENEZIANI, G.R. ; SAKURABA, R.K.; CAMPOS, L.L. . Quality control in “Intensity Modulated Radiation Therapy-IMRT” using thermoluminescent dosimeters. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction Quality assurance in radiation therapy included all actions for ensure the maximum dose for the target volume (tumour) and minimum dose for the healthy tissues. The use of thermoluminescent detectors for evaluation of the absorbed doses in treatments that involve the use of ionizing radiation is widespread and well established in clinical routine. The quality measures are employed to validate system performance, such as IMRT quality assurance (QA). An example for IMRT QA is the decision not to treat the patient if the comparison between a point-dose measurement and the planned value exceeds a predefi ned acceptance criterion (±5%). This work aimed the evaluation of absorbed doses with the use of thermoluminescent detectors (TLDs) of lithium fl uoride doped with magnesium and titanium (LiF:Mg,Ti) and a polymethylmethacrylate (PMMA) phantom in Intensity Modulated Radiation Therapy – IMRT planning. Methods In this study the PMMA phantom simulated a patient in treatment. The central cavity (rectangular format) was considered like target volume (tumour) and the others four cavities were considered like organs at risk. The TLDs were positioned inside the cavities; each cavity has an EVA mold for the positioning of TLDs.

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  • IPEN-DOC 26813

    CORREA, J.N.; PASCHUK, S.A.; BARRETO, R.C.; DENYAK, V.; SCHELIN, H.R.; NARLOCH, D.C.; DEL CLARO, F.; HASHIMOTO, Y.; MATIN, A.C.; SILVA, A.C.M.; ZAHN, G.S. ; SILVA, P.S.C. . Evaluation of the maximum emitting layer of Rn-222 in cementitious building materials. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction – Radionuclides present in construction materials are of interest in the view of environmental radioactivity. The limitations established have focused on the concentration of Ra-226 and the consequent exhalation of Rn-222. A physical/mathematical model developed at the Laboratory of Applied Nuclear Physics (LFNA/UTFPR) correlates the exhaled Rn-222 with the Ra-226 inherent to the material. The model considers the exhalation of Rn-222 by a plane surface that simulates exhalation in fl oors, walls and ceilings. Determination of the maximum emitting layer of Rn-222 that effectively exhales is important to support the model. The objective of this research is to determine the maximum emissive layer of Rn-222 that provides internal diffusion and exhalation of radon-222 in cementitious materials. Methods - Cylindrical samples were made of common cement paste and cement paste with sand of high Ra-226 concentration. The samples (thicknesses 1 to 5 cm) were sealed in order to ensure the exhalation of Rn-222 through one surface. Samples and diffusion chambers containing CR-39 solid-state detectors were inserted into a glass vessel. The samples/detectors were stored for 30 days. Subsequently, the detectors were chemically etched and the nuclear tracks in the CR-39 detectors were counted. Results – For each type of sample a curve was fi tted whose threshold indicated the maximum emitting layer. The results obtained on the samples of common cement paste indicated a maximum emitting layer of 2cm. For samples of cement paste with sand with high Ra-226 concentration, no threshold was observed, indicating that the maximum emitting layer is greater than 5cm. Conclusions - The maximum emitting layer thickness of Rn-222 of common materials determined by curve fi tting was 2cm. For materials with high concentration of Ra-226 there is an indication that the emitter layer is larger than 5cm. The obtained results subsidize the physical/mathematical model developed in the LFNA/UTFPR.

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  • IPEN-DOC 26812

    OLIVEIRA, LUCAS N. de ; NASCIMENTO, ERIBERTO O.; MORAIS JUNIOR, PEDRO A.; ANTONIO, PATRICIA L. ; CALDAS, LINDA V.E. . Dosimetric characterization of high-linearity bone radiation detector exposed to gamma-rays. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction In radiation physics, the study of new alternative dosimeters is of interest on the growing branch of dosimetric characterization of solid-state dosimeters for radiotherapy applications in the Medical Physics fi elds. There are innumerous emerging techniques for reading and processing multivariate data to assess the possible linear behavior of dosimeters; such methods are the multivariate calibration Partial Least Square Regression (PLSR) and Principle Component Regression (PCR) techniques. The goal of this work was to expose bone samples to high doses and to use the FTIR spectrophotometry technique to evaluate the sensitivity and linearity of the absorbed profi les using PLSR and PCR analyses. Methods Small cubes with size approximately of 0.5 cm3 composed the bone samples, used in this work. The samples were irradiated in triplicates, with absorbed doses of 10, 100, 250, 400 and 500 Gy using a 60Co Gamma Cell-220 system (dose rate of 1.089 kGy/h); afterwards, the absorbance spectrum of each sample was acquired on a Fourier Transform Infrared (FTIR) Spectrometer (Frontier/Perkin Elmer) with an optical step of 1 nm from 400 nm to 4000 nm. Results The absorbance for high sensitivity peaks was observed for each bone sample, at the 552 nm, 991 nm and 1650 nm wavelengths in decreasing magnitude. The PLSR and PCR techniques showed, on the range from 10 Gy to 500 Gy, for the calibration curves of the system, a linearity of 0.9432 and 0.9422 respectively, using just three components on both methods. Conclusions The results indicate an acceptable linear response, and therefore this material may be an interesting radiation detector.

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  • IPEN-DOC 26811

    VILLANI, D. ; RODRIGUES JUNIOR, O. ; DANTAS, B.M.; CAMPOS, L.L. . Dosimetric characterization of 3D printed phantoms at different infill percentage for diagnostic x-ray energy range. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction The use of 3D printing and fi laments commonly found commercially for development of phantoms has been investigated in recent years due to the cost of materials and improvements in the quality of printers. The application of this technique for radiation protection and dosimetry requires a complex study of the quality control and the interaction of printed materials with different radiation beams. The aim of this paper is to characterize 3D printed phantoms and printing set-ups for different infi ll percentages for diagnostic energy beams. Methods 3D printing performance was studied using the RAISE 3D PRO2 printer from IPEN for printing with PLA (Polylactic Acid) and ABS (Acrylonitrile Butadiene Styrene) fi laments. Printing characteristics such as repeatability, reproducibility, effective density by displaced water mass and porosity at 100% infi ll were studied. Plate samples of 8x8x1cm3 were printed and, using the Pantak Seifert irradiator with different x-ray qualities in the diagnostic energy range, the attenuation coeffi cients were obtained experimentally for different percentages of plates infi ll. Results By printing three identical samples for each print mode, the 3D printing system had a repeatability better than 1.0% for masses and average of 0.7% for the dimensions of the printed objects, obtaining the highest variations in small printed parts. Little to no porosity has been found on the printed pieces with 100% infi ll, giving to the printed objects the same density of the chosen fi lament. The attenuation coeffi cients were determined for the different beam qualities and it was verifi ed that the variation in the values decreases as the infi ll quality increases. Conclusions The results show that the printing system have excellent repeatability and print quality. The different printing modes characterized together with their attenuation coeffi cients for the x-ray beams will be studied and used in the development of new 3D printed phantoms in our institute.

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  • IPEN-DOC 26810

    OLIVEIRA, LUCAS N. de ; NASCIMENTO, ERIBERTO O.; ANTONIO, PATRICIA L. ; CALDAS, LINDA V.E. . Evaluation of transparent and black commercial soda-lime glass irradiated with gamma radiation. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction The linearity characteristic in radiation dosimetry presents a growing interest. Glasses have been applied to radiation high doses. The goal of this work was to expose transparent and dark commercial soda-lime glasses samples to high doses and to use the UV-Vis spectrophotometry technique for their evaluation. Methods Transparent and dark commercial soda-lime glasses with dimensions of 1 x 10 x 40 mm3 were irradiated with doses from 1 kGy to 10 kGy using a 60Co Gamma-Cell system 220, and then were evaluated with the UV-Vis technique. The sensitivity and linearity characteristics were evaluated with the absorbed profi les of the multivariate calibration Partial Least Square Regression (PLSR) and Principle Component Regression (PCR) techniques. Results The PLSR and PCR techniques showed, on the range of 1-10 kGy, for the calibration curves, of transparent and black commercial soda-lime glass, linearity values of 0.9432 and 0.9422 respectively using just three components on both methods. The spectra present a baseline variation (and maximum absorbance values) proportional to the absorbed dose received by the samples. These results show that it is possible to use the technique of UV-Vis to determine if the glass samples were irradiated or not. The color changes for transparent glass irradiated with absorbed doses from 1 kGy up to 10 kGy. This color variation in relation to absorbed dose indicates that the glasses may be used as YES/NO dosimeters. Conclusions The UV-Vis measurements may be useful in gamma radiation dosimetry, using the spectra of irradiated glasses; the highest linearity was shown in order respectively for transparent and black commercial soda-lime glass; the glass samples changed their coloration proportional to the absorbed doses, and they may be used as Yes/No detectors and as high-dose dosimeters. The results indicate a good linear response and the radiation detectors present potential use for radiation dosimetry in high doses.

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  • IPEN-DOC 26809

    GONCALVES, J.A.C. ; MANGIAROTTI, A.; ASFORA, V.K.; KHOURY, H.J.; BUENO, C.C. . Dosimetric characterization of thin diodes in an electron beam facility for radiation processing. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction: Silicon diodes have been employed as relative dosimeters in clinical photon and electron beams. However, they are prone to radiation damage that produces a drop of their current sensitivities with increasing accumulated doses. This effect is attributed to the decrease of the minority carrier diffusion lengths which diminishes the sensitive volume of the diode. Theoretically, it is possible to mitigate the decay of the current sensitivity by choosing diodes with thicknesses smaller than the lowest minority carrier diffusion lengths anticipated for the foreseen accumulated dose. This surmise has been followed up in this work by evaluating the response of thin diodes (SFH00206K) for the dosimetry of electron beams used in radiation processing. Methods: The diode with 10 μm of depletion layer at 0V was produced on n type Si wafers of 220 m thickness. As a dosimeter, the device was housed in a probe and connected to an electrometer to be operated in short-circuit current mode without bias voltage. To carry out the irradiation, the probe was placed on a conveyor belt that crosses the radiation fi eld of a 1.5 MeV electron beam. Results: The currents were registered as a function of the exposure time for dose-rates within 2-8 kGy/s and accumulated doses up to 350 kGy. The dosimeter was characterized with respect to the linearity between current and dose-rate, repeatability and reproducibility of the current signals. Its lifespan was investigated, particularly addressing the stability of the current sensitivity factor with increasing absorbed doses. The measurements were benchmarked against calculations of the current taking into account the fraction of the electron energy deposited in the active volume of the diode, the dose-rate, and the values of diffusion lengths. Conclusion: All experimental data so far obtained prove that this diode can be used in electron beam dosimetry. Furthermore, a fair agreement was found between theoretical and experimental results.

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  • IPEN-DOC 26808

    POLO, IVON O. ; SANTOS, WILLIAM S. ; CALDAS, LINDA V.E. . An extrapolation chamber for the establishment of a primary radiation standard in 85Kr and 147Pm beta radiation beams. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction At the Calibration Laboratory (LCI) of the IPEN/CNEN, studies are in development on the establishment of the Böhm extrapolation chamber model 23392 as a primary standard system for the dosimetry and calibration of beta-radiation sources and detectors. This chamber was already characterized at the LCI in 90Sr/90Y beams using two different entrance windows: one of aluminized Mylar and another of Hostaphan. This extrapolation chamber was characterized in 85Kr and 147Pm beams. All tests were carried out with the reference 90Sr /90Y source, for comparative purposes. Methods A Keithley model 6517B electrometer was used for the measurements. The utilized radiation sources are part of the Beta Secondary Standard BSS2. Moreover, the Monte Carlo code MCNP5 was used to determine the absorbed dose rates and to compare them with the experimentally determined dose rates and with those from the PTB calibration certifi cate. Results Saturation curves, ion collection effi ciency, ion recombination, polarity effect, response stability, real null depth, linearity of response, variation of response as a function of sourcedetector distance, extrapolation curves, correction factors and absorbed dose rates were obtained. The ion collection effi ciency was greater than 99%; the ionic recombination was less than 1%, and the polarity effect was greater than 1%. The stability of the response was lower than 0.15% for the repeatability test, and it was less than 0.36% for the reproducibility test. The difference between the experimental absorbed dose rates and those from the Monte Carlo model, compared to those from the calibration certifi cate, was less than 1.9% for all sources. Conclusions All results of the performed tests are within the limits of the international recommendations. The results for the 90Sr/90Y source were in the good agreement with previous works performed at LCI. These results are suitable for the establishment of a primary standard for beta radiation.

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  • IPEN-DOC 26807

    OTERO, ANDRE G.L. ; MARUMO, JULIO T. ; POTIENS JUNIOR, ADEMAR J. . Applying deep-learning in gamma-spectroscopy for radionuclide identification. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction Neural networks, particularly deep neural networks, are used nowadays with great success in several tasks, such as image classifi cation, image segmentation, translation, text to speech, speech to text, achieving super-human performance. In this study we explore the capabilities of deep learning on a new fi eld: gamma-spectroscopy analysis. Using a well-known deep neural network architecture with gamma spectroscopy data, we successfully identify the radionuclides (Am-241, Ba-133, Cd-109, Co-60, Cs-137, Eu-152, Mn- 54, Na-24 and Pb-210) contained in several experiments. This neural network is also capable to identify different mixed radionuclide in the same source, demonstrating that deep neural networks can be successfully applied on gamma-spectroscopy analysis. Methods Using a HPGe detector to acquire several gamma spectra, from different sealed sources, we created a dataset that was used for the training and validation of the neural network. We created our deep neural network using python as programing language, alongside with Keras, a deep learning framework. Applying the VGG19 network architecture, except by the last layer which using softmax as activation function, we used sigmoid in order to allow classifi cation of not mutually exclusive classes in the same instance. Results After 250 epochs of training the classifi cation error on the training and test datasets reached a minimum, the same occurred with accuracy. As a fi nal test we used a spectrum from a triple sealed source, containing Am-241, Cs-137 and Co-60. As this kind of data was never seen by the network before we expect that the network generalizes well and correctly classify the spectra as containing the three isotopes. When applying the new data, the model correctly classifi ed the spectra as containing the tree radionuclide. Conclusions The model successfully classifi es different spectra with different radionuclides and his performance is good on never seen before data (the triple source sealed) demonstrating that deep learning can be used on a new domain.

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  • IPEN-DOC 26806

    SAVI, MATHEUS; BERTONCINI, MARCO A.; POTIENS, MARIA da P.A. . Commercial filament testing for use in 3D printed phantoms. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction With the popularization of 3D printing, many areas of knowledge are using this technology to create products and diminish costs, even in health segment. Commercial phantoms are expensive and hard to obtain in development countries. As alternative, 3D printed phantoms can be the way to produce inexpensive and reliable simulators aimed for dosimetry and teaching. That said, the objective of this study is to determine which of the available commercial fi laments can be used in 3D printing to mimic human tissue for use in 3D printed phantoms. Methods Fourteen 3D printing fi laments (ABS, ABS premium, PLA, PLA+Bone, PLA+aluminum, PLA+brass, PLA+cooper, SILK, HIPS, PETG, PVA, Wood, TPU and TPE) commercially available in Brazil had their attenuation tested, using computed tomography. Each material was printed as 2 centimeters edge cube with rectilinear pattern and 60, 80 and 100 percent infi ll. The cubes were scanned in a Philips CT Brilliance 6 with 120 kV, 200 mA, 2mm slices and standard reconstruction. At the center of each cube, an ~ 120 mm² region of interest were set to measure the mean Hounsfi eld Unit (HU) and the standard deviation value. For each material a graphic was plotted and the curve equation determined. Results The HU of the tested materials ranged from -516,2 ± 7,3 to 329,8 ± 18,9. All human tissues could be mimetized with these materials, except bone (mainly cortical bone). Considering the curve equation, the most promising fi lament was PLA+Cooper, due to the multiple infi ll confi guration that allows the resulting HU range to represent from adipose and skin tissue to marrow bone. With a two extruder printer may be possible add lung tissue to the model and make a 3D phantom more complex and accurate. Conclusions With these tested materials, is possible to construct various phantoms, simulating a wide range of tissues. However, any simulator with cortical bone is impaired because none fi lament achieve the required HU value (at least over 800 HU).

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  • IPEN-DOC 26805

    NASCIMENTO, ERIBERTO O.; BECATTI, MATHEUS J.P.; ANTONIO, PATRICIA L. ; VIEIRA, SILVIO L.; OLIVEIRA, LUCAS N. de ; CALDAS, LINDA V.E. . Quality control of solar protection films via design of experiments. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 3rd, May 27-31, 2019, Lisboa, Portugal. Abstract... Lisboa, Portugal: C2TN, Instituto Superior Técnico, Universidade de Lisboa, 2019.

    Abstract: Introduction Solar radiation reaching the earth surface is broadly divided into infrared, visible and ultraviolet radiation (UVR). Individual dosimetry and monitoring of the sun rays in humans and environments is of interest since in homes, shops and cars the effects of UVR radiation can bring irreparable damage to the skin and eyes. The effi cacy of solar protective fi lms has been recognized as an important public health product. The objective of this work was the quality control of solar fi lms using the UV-Vis spectroscopy technique via 2k Experimental Factor. Methods Four types of solar protective fi lms were tested: G05, G20, G35 and WB (Windom Blue), which follow the blocking of UVR rays by 95%, 80%, 65% and 0% (76% transparent). The samples had dimensions of 1.0 x 3.0 cm2 and the readings were taken on a GENESYS™ 10S UV-Vis Spectrophotometer with an optical step of 1 nm from 190 nm to 400 nm. The absorbances were used in a 2k Experimental Factor, in which the four fi lms were read individually and also with overlap (two fi lms together). It was possible to obtain results of all the interactions among the fi lms, with or without overlap. Results The results about the absorption of the sunscreen fi lms were modeled from the 2k Experimental. This factor indicates that the best regions of the spectrum are blocked and/or where they produce a better quality control of these materials. The region studied in this work was where the ultraviolet radiation dosimetry can be of interest. The proposed spectrophotometric method is rapid, simple and cost effective for the evaluation on quality control of protection fi lms. Conclusions The results provide information on ultraviolet radiation and they can be useful for the medical physics community. The proposed methodology may be useful as a rapid quality control tool. It can be used during the production process, in the analysis of the fi nal product, and can offer important information for the scientifi c community.

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  • IPEN-DOC 26804

    ROSSI, MARIANA C.; BAYERLEIN, DANIEL L.; KRIECK, ANDRE M.T.; BRANDÃO, JAQUELINE de S.; PFEIFER, JOÃO P.H.; ROSA, GUSTAVO dos S.; STIEVANI, FERNANDA de C.; MARTINEZ, LUIS G. ; SAEKI, MARGARIDA J.; ALVES, ANA L.G.. Influence of space holder on the biocompatibility of Ti-34Nb-6Sn alloy prepared by powder metallurgy. In: INTERNATIONAL MATERIALS RESEARCH CONGRESS, 28th, August 18-23, 2019, Cancun, México. Abstract... Ciudad de México, México: Sociedad Mexicana de Materiales, 2019.

    Abstract: Development of metallic materials for denistry and orthoapedic area have been increasing, due to in world life expectancy and the significantly numbers of accide nts. Due to problems of failure in available commercial materials implantation, as well as the discomfort of patient because the high elastic modulus, these devices need to be improved or news implants should be sought. This study was intended to develop a porous alloy, Ti-34-Nb-6Sn/Mg wich can help the ingrowth bone tissue when implanted, by the powder metallurgy. After the milling powders in the high energy mill, were compacted and sintered. Both, powders and sintered materials were chacarterized by X-ray Difraction (XRD), Scanning Electron Microscopy (SEM) and semi-quantitative compositional analysis (EDS). The apparent porosity was measured through the Arquimed’s Method. The toxicity this material was evaluated by MTT assay, using the equine mesenchemal stem cells derivated of bone marrow (bmMSC) according to ISO 109935. The bmMSCs morphological analysis in contact on the material surface using SEM. The Mg evaporation was confirmed by EDS and XRD after sintering. The XRD indicate there is predominantly beta phase than alpha. The apparent porosity was higher in alloy with Mg space holder. The materials do not presented particular cytotoxic in direct and indirect contact. Metallurgic powder tecnhique promoted effectively macropores formation in Ti-34Nb-6Sn/Mg alloy, wich possibly further bmMSCs adhesion.

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  • IPEN-DOC 26803

    SAEKI, MARGARIDA J.; GARCIA, JOÃO I.M.M.; FERNANDES, CELIO J.C.; ROSSI, MARIANA C.; SILVA, WILLIAM de M.; MARTINEZ, LUIS G. ; ZAMBUZZI, WILLIAN F.. Characterization of titanium surface modified by calcium titanate. In: INTERNATIONAL MATERIALS RESEARCH CONGRESS, 28th, August 18-23, 2019, Cancun, México. Abstract... Ciudad de México, México: Sociedad Mexicana de Materiales, 2019.

    Abstract: Coatings based on apatite and others that contain calcium play an important role for the osseointegration with the implant. It is believed that released calcium induces a specific biological response to the living tissue establishing a stable chemical bonding between formed bone and implants. The mechanical anchorage of implants also depends on the surface structure and morphology. In this work, the titanium surface was modified by calcium titanate, which was deposited by sol-gel method combined to the dip coating technique followed by heat treatments. Two different emersion rate (5 and 10 cm/min) were used as well as the number of coatings were varied. The temperature of this treatment was established based on the results of the thermal analysis (TG/DTA). The surfaces were characterized by X-ray diffractometry (DRX), Scanning Electron Microscopy (SEM) and water contact angle measurement. The corrosion behavior of modified surfaces was evaluated by electrochemical method (polarization curves) in balanced saline Hanks solution. Finally, biological test was carried out by the analysis of cellular viability and adhesion of MC3T3-E1 (subclone 4), mouse pre-osteoblastic cells (ATCC CRL-2593), using MTT and crystal violet assays, respectively, after 24h incubation at 37oC in 5% CO2 atmosphere. The coating consists of anatase TiO2 (PDF 21-1272) and calcium titanate (CaTiO3, PDF 43-226). SEM analysis showed that homogeneous films with 0.8μm of thickness are provided when they are prepared by only one immersion and that the films increase the resistence to corrosion. The coating increases the wettability as the water contact angle decreases from 90o±10o for cp Ti (low interstitial titanium) to 34 o±5o. The biological test shows that the modifications do not interfere on the osteoblast viability and adhesion, however, the morphological analysis of preosteoblasts cultured on the modified Ti-surface by SEM shows that the coatings promote a cell spreading.

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  • IPEN-DOC 26802

    SILVA, ANDERSON M.B.; JUNOT, DANILO O. ; SOUZA, LUIZA F.; SOUZA, DIVANIZIA N.; CALDAS, LINDA V.E. . Caracterização do CaSO4:Tb,Ag para dosimetria OSL. In: CONGRESSO BRASILEIRO DE FÍSICA MÉDICA, 24., 21-24 de agosto, 2019, Santos, SP. Resumo expandido... São Paulo, SP: Associação Brasileira de Física Médica, 2019.

    Abstract: Embora a dosimetria por OSL seja bem conhecida, o uso dessa técnica tem sido pouco difundido devido à limitação de materiais. Conforme resultados da literatura, a prata como co-dopante em matrizes de CaSO4 dopado com terras raras proporciona um aumento da intensidade das emissões luminescentes em comparação aos materiais sem a prata. Sendo assim, como não há relatos sobre a caracterização estrutural e dosimétrica do CaSO4:Tb com a incorporação de prata, a proposta do presente trabalho foi produzir e caracterizar policristais de CaSO4 dopado com térbio e co-dopado com óxido e nanopartículas de prata. Os fósforos apresentaram uma curva típica de decaimento exponencial de OSL. As amostras de CaSO4:Tb,Ag(nanopartícula) apresentaram sensibilidade OSL cerca de 4 vezes mais intensa em comparação com CaSO4:Tb,Ag(óxido). Ambas as amostras apresentaram curva dose resposta linear na faixa de dose observada e limite inferior de detecção (LID) de 9 mGy para o CaSO4:Tb,Ag(nanopartícula) e 32 mGy para o CaSO4:Tb,Ag(óxido).

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  • IPEN-DOC 26537

    PRESTES, JOAO C.A. ; POTIENS, MARIA da P.A. ; XAVIER, MARCOS . Caracterização de um sistema irradiador utilizado em radioterapia para calibração de dosímetros clínicos. In: CONGRESSO BRASILEIRO DE FÍSICA MÉDICA, 24., 21-24 de agosto, 2019, Santos, SP. Resumo expandido... São Paulo, SP: Associação Brasileira de Física Médica, 2019.

    Abstract: Este trabalho apresenta as etapas de adequação e caracterização de um irradiador de 60Co, que era utilizado para tratamento para que seja utilizado em procedimentos de calibrações de dosímetros clínicos utilizados em radioterapia. Foi realizado a adequação de um sistema irradiador doado ao Laboratório de Calibração do Ipen e a caracterização do feixe e do campo de radiação, de acordo com as recomendações do guia da AIEA (TRS 469, 2009). Para a instalação do novo irradiador, foi realizada uma adaptação na atual sala de calibração para acomodar o cabeçote na posição de calibração. Um suporte foi confeccionado para o seu posicionamento. Na sequência foi necessária a correção no sistema de colimação que apresentou falhas na sua utilização. Para a caracterização do feixe de radiação foram realizados os testes iniciais de uniformidade do campo de radiação determinando o tamanho e o centro do feixe de radiação. Utilizando uma câmara de ionização de pequeno volume foi encontrada uma uniformidade maior do que 90% tanto no sentido vertical como no horizontal, para um feixe de radiação de 8 x 8 cm. As medições para a determinação das taxas de kerma no ar realizadas demonstram que o sistema está pronto para ser utilizado na calibração.

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  • IPEN-DOC 26801

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

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

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  • IPEN-DOC 26800

    SILVA, J.C.M.; NTAIS, S.; RAJARAMAN, V.; ANTONIASSI, R.M. ; SPINACE, E.V. ; BARANOVA, E.A.. The catalytic activity of PtRu nanoparticles for ethylene glycol and ethanol electrooxidation in alkaline media. In: ANDRADE, ADALGISA R. de (Ed.); ALMEIDA, ERICA J.R. de (Ed.); OLIVI, PAULO (Ed.) SIMPÓSIO BRASILEIRO DE ELETROQUÍMICA E ELETROANALÍTICA, 22nd, 1-5 de setembro, 2019, Ribeirão Preto, SP. Resumo... Ribeirão Preto, SP: Sociedade Brasileira de Eletroquímica e Eletroanalítica, 2019. p. 266-266.

    Abstract: The use of excessive fossil fuels has resulted in harmful effects on the environment and potentially human health. In this sense, direct alcohol fuel cells DAFCs are promising energy producing devices. Ethanol and ethylene glycol are appealing fuels for DAFCs due to their lower toxicity and high theoretical energy density, 8.01 kWh kg−1 and 5.2 kWh kg−1, respectively [1,2]. In this study, the carbon-supported PtRu nanoparticles with atomic ratios of Pt:Ru of 100:0, 90:10, 70:30 and 50:50 for ethanol and ethylene glycol electrooxidation in alkaline media, was investigated. The nanoparticles were synthesized using sodium borohydride method with 20 wt% of metals loading on carbon [1]. X-ray diffraction (XRD) analysis revealed that Pt and PtRu electrocatalysts have face centered cubic (fcc) structure and suggests the alloy formation for all PtRu/C materials, which was further supported by the X-ray Photoelectron Spectroscopy (XPS). According to transmission electron microscopy (TEM) the nanoparticle mean sizes were 7.3 nm, 5.7 nm, 5.2 nm and 5.1 nm for Pt/C, Pt90Ru10/C, Pt70Ru30/C and Pt50Ru50/C, respectively. Electrochemical measurements carried out in mol L-1 KOH + mol L−1 alcohol solution (ethanol and ethylene glycol) in a conventional three-electrode electrochemical cell (glassy carbon was used as work electrode and a platinum foil and a Hg/HgO were used as the counter and reference electrodes, respectively) demonstrated that the addition of Ru to Pt enhances the catalytic activity towards ethanol and ethylene glycol electrooxidadion in alkaline media. The catalyst of Pt50Ru50/C composition showed the lowest onset potential for ethanol and ethylene glycol electrooxidation (by Cyclic voltammetric), which are 160 mV and 70 mV lower than for Pt/C, respectively. Furthermore, this catalyst outperformed Pt/C and other PtRu/C compositions in chronoamperommetric and direct alcohol fuel cell (DAFC) experiments. DAFC experiments using Pt50Ru50/C as anode had the power density 40% and 14 % higher than using Pt/C for ethanol and ethylene glycol, respectively. The enhancement of the catalytic activity might be related to the high amount of oxides species on the Pt50Ru50 electrocatalysts surface, which could form Ru-OH at low potential and also due to the electronic effect of PtRu alloy that weakens the adsorption strength of poisonous intermediates from reactions [3].

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  • IPEN-DOC 26799

    BIANCOLLI, A.L.G.; LOPES, T. ; PAGANIN, V.A.; TICIANELLI, E.A.. Electrocatalysts and membranes for using in PEMFCs and AEMFCs fed by contaminated hydrogen. In: ANDRADE, ADALGISA R. de (Ed.); ALMEIDA, ERICA J.R. de (Ed.); OLIVI, PAULO (Ed.) SIMPÓSIO BRASILEIRO DE ELETROQUÍMICA E ELETROANALÍTICA, 22nd, 1-5 de setembro, 2019, Ribeirão Preto, SP. Resumo... Ribeirão Preto, SP: Sociedade Brasileira de Eletroquímica e Eletroanalítica, 2019. p. 417-417.

    Abstract: Catalytic ethanol dehydrogenation has been proposed as a promising method to produce H2 without CO and CO2.¹ However, the dehydrogenation generates other types of organic by-products such as ethyl acetate, acetaldehyde and leaves unreacted ethanol that can cause power losses in the fuel cell. To make this technology accessible, fuel cells performances must be improved. In this context, we studied the influence of the main contaminants present in the hydrogen produced by the catalytic dehydrogenation of ethanol on the performance of proton exchange membrane fuel cells (PEMFCs) and anion exchange membrane fuel cells (AEMFCs). Investigations comprised the elucidation of the processes and reactions involved in the corresponding electrode systems, as well as the phenomena governing the electrochemical performance in the alkaline and acidic media, and in the absence and in the presence of the by-products. For the AEMFCs, the research initially involved the syntheses of ionomers and membranes and the optimization of their performances in single cells, using pure hydrogen and conventional electrocatalysts (Pt-Ru/C in the anode and Pt/C in the cathode).² However, due to the chemical instability when exposed to the contaminants, these materials seem to undergo degradation, leading to almost total and irreversible losses of the cell performance. A positive fact was that AEMs showed much less crossover of contaminants from the anode to the cathode. Through analyses by different techniques, it was found that unreacted ethanol is the main poison in the case of PEMFCs, with acetaldehyde and ethyl acetate having minor contributions. Different anodic and cathodic catalysts were tested in order to obtain better fuel cells performances, such as Pt-Sn/C, Pt- W/C, Pt-Co/C, Pt-Cr/C and Pt/C (Fig. 1). Also different types of membranes were tested (Nafion® 115, 117, and 212). The best result was achieved when the Pt- Co/C catalyst was used at the cathode (with Pt/C at the anode), for which the loss of power density was only 20% compared to a cell fed by pure H2 and with Pt/C on both electrodes (working at 0.7 V).

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  • IPEN-DOC 26798

    SILVA, R.P. ; SOUZA, R.F.B. de ; SANTOS, C.M.G. ; SILVA, A.J.; SANTIAGO, E.I. . Development of non-fluorinated membranes based on PBI for application in high temperature fuel cells (HT-PEM). In: ANDRADE, ADALGISA R. de (Ed.); ALMEIDA, ERICA J.R. de (Ed.); OLIVI, PAULO (Ed.) SIMPÓSIO BRASILEIRO DE ELETROQUÍMICA E ELETROANALÍTICA, 22nd, 1-5 de setembro, 2019, Ribeirão Preto, SP. Resumo... Ribeirão Preto, SP: Sociedade Brasileira de Eletroquímica e Eletroanalítica, 2019. p. 460-460.

    Abstract: Most of Proton Exchange Membrane Fuel Cells (PEMFCs) use the Nafion as electrolyte, which has a limitation in the operating temperature. Usually, these cells operate up to 80°C since the proton conduction is dependent on water molecules carriers. The increase in the operating temperature of a PEMFC cell is desired due to the contribution of the temperature in the acceleration of the electrochemical reactions, which are thermoactivated processes. In the context of searching alternative polymeric electrolytes, PBI (polybenzimidazole) membranes have been considered a promising membrane for high temperature operating PEMFC (HT-PEMFC) due to the combination of satisfactory proton conduction in conditions of low relative humidity (RH) and excellent thermal stability. Pure PBI membranes were prepared by casting a solution of PBI / N, N'-dimethylacetamide (DMAc) and doped with phosphoric acid at different times (1, 3, 5, 7 10 and 15 days). Each membrane was evaluated in Fuel Cell tests, doping level and online Raman tests in order to determine effects of doping level, chemical degradation and fuel cell performance. The electrodes were optimized by studying different catalytic layer composition and the cell tested at different operational conditions.

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  • IPEN-DOC 26797

    GUIMARÃES, V.P.; NANDENHA, J. ; FATIBELLO-FILHO, O.; NETO, A.O. ; VICENTINI, F.C.; ASSUMPÇÃO, M.H.M.T.. Development of nanomaterials for formate electrochemical oxidation aiming sustainable energy generation. In: ANDRADE, ADALGISA R. de (Ed.); ALMEIDA, ERICA J.R. de (Ed.); OLIVI, PAULO (Ed.) SIMPÓSIO BRASILEIRO DE ELETROQUÍMICA E ELETROANALÍTICA, 22nd, 1-5 de setembro, 2019, Ribeirão Preto, SP. Resumo... Ribeirão Preto, SP: Sociedade Brasileira de Eletroquímica e Eletroanalítica, 2019. p. 436-436.

    Abstract: The world energy system is highly depended of fossil fuels, which is not sustainable [1]. Thus, the use of alternative energy is crucial and fuel cells are being considered good options. In this context, this work aimed to develop electrocatalysts based on palladium nanoparticles (PdNPs) supported on the physical mixtures of carbon (Vulcan XC72) and titanium dioxide (P25) toward formate oxidation in alkaline medium and its application in formate fuel cells. The materials were synthesized by the borohydride reduction method [2] with 20% (m/m) of metal loading and in two batches. In the first batch, the PdNPs were reduced in the physical mixture of carbon (C) and titanium dioxide (TiO2), in different proportions of C and TiO2, identified as Pd/(C+TiO2), while in the second one, the PdNPs were reduced only in TiO2 with later incorporation of C which were identifies as Pd/TiO2-C. On both batches, the ratios between C and TiO2 used were 75:25, 50:50 and 25:75 (m/m). A reference material, complied of PdNPs supported just on C (Pd/C) was also prepared. All materials were characterized by X-ray diffraction, showing peaks of the face-centered-cubic (fcc) structure of the Pd, as well as TiO2 peaks of anatase and rutile phases. Transmission Electron Microscopy (TEM) were also evaluated showing an average particle size between 3 and 8 nm. Electrochemical experiments considering voltammetry and chronoamperometry showed that the materials with PdNPs reduced in the TiO2 (Pd/TiO2-C) were more promising when compared to Pd/(C+TiO2), and among them Pd/TiO2-C 75:25 presented the highest current observed in chronoamperometry. Comparing the Pd/(C+TiO2) materials, the Pd/(C+TiO2) 50:50 presented the highest current. Taking into account single cell experiments, although the electrochemical results evidenced the improvement toward formate with PdNPs deposited firstly in the TiO2, the fuel cell tests showed the opposite, presenting the best cell efficiencies with Pd/(C+TiO2) materials, where Pd/(C+TiO2) 75:25 (ratio between C and TiO2) was the best material with the highest power density obtained. This fact can be explained by the higher conductivity of C, in a higher proportion, coupled with the small amounts of TiO2, which provides oxygenated species that facilitate the formate oxidation.

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  • IPEN-DOC 26796

    ZAMBONI, CIBELE B. ; ALMEIDA, MATEUS R. de ; MEDEIROS, JOSE A.G. de. Análise de zinco em sangue de corredores de longa distância / Zinc analysis in blood of long-distance runners. In: CONGRESSO BRASILEIRO DE CIÊNCIAS DO ESPORTE, 21st; CONGRESSO INTERNACIONAL DE CIÊNCIAS DO ESPORTE, 8th, September 15-20, 2019, Natal, RN. Resumo expandido... Porto Alegre, RS: Colégio Brasileiro de Ciências do Esporte, 2019.

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  • IPEN-DOC 26795

    ZAHN, GUILHERME S. ; GENEZINI, FREDERICO A. ; MORALLES, MAURICIO . Evaluation of peak-fitting software for gamma spectrum analysis. In: REUNIÃO DE TRABALHO SOBRE FÍSICA NUCLEAR NO BRASIL, 42.; ENCONTRO NACIONAL DE FÍSICA DE PARTÍCULAS E CAMPOS, 40., 1-5 de setembro, 2019, Campos do Jordão, SP. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2019.

    Abstract: In all applications of gamma-ray spectroscopy, one of the most important and delicate parts of the data analysis is the fitting of the gamma-ray spectra, where information as the number of counts, the position of the centroid and the width, for instance, are associated with each peak of each spectrum. Theres a huge choice of computer programs that perform this type of analysis, and the most commonly used in routine work are the ones that automatically locate and fit the peaks; this fit can be performed in several different ways - the most common are either to fit a Gaussian function to each peak or simply to integrate the area under the peak, but some software go far beyond and include several small corrections to the simple Gaussian peak function, in order to compensate for secondary effects. In this work several gamma-ray spectroscopy software are compared in the task of finding and fitting the gamma-ray peaks in spectra taken with some calibrated standard sources. The results allow for a discussion on the performance of each software in the tasks of identifying and determining the correct area of the gamma-ray peaks, as well as on the advantages and difficulties in using automatic programs when comparing with a manual peak-fitting software, used as reference.

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  • IPEN-DOC 26540

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

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

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  • IPEN-DOC 26794

    ZAMBONI, CIBELE B. ; GIOVANNI, DALTON N.S. ; MIURA, VINICIUS T.; GOMEZ, MONICA R.. Identificação de processos fotográficos utilizando a técnica de FRX. In: SIMPOSIO LATINOAMERICANO DE FÍSICA Y QUÍMICA EN ARQUEOLOGÍA ARTE Y CONSERVACIÓN DE PATRIMONIO CULTURAL, 7th, September 9-13, 2019, Ciudad de México, México. Abstract... Ciudad de México, México: Universidad Nacional Autónoma de México, 2019. p. 7-7.

    Abstract: O conhecimento da composição elementar de artes gráficas é de grande interesse para investigações de caráter histórico-artístico na medida em que possibilita identificar o processo de produção, a época de sua manufatura e, em alguns casos, sua procedência. Nos últimos anos, no Brasil, essas investigações têm adquirido relevância e estão sendo empregadas em acervos fotográficos pertencentes a museus, galerias de artes e a colecionadores particulares. As primeiras fotos tomadas em solo brasileiro datam de 1840 época da daguerreotipia. Desde então, com seu aperfeiçoamento, a fotografia tomou lugar de relevância cultural e viabilizou a geração de acervos particulares, sendo que muitos necessitam de devida caracterização, afim de situar o “objeto” dentro do contexto de sua própria época, além de agregar informações que auxiliem sua conservação e preservação. Atualmente a peritagem de obra de arte está crescendo no Brasil, em decorrência, estas informações podem agregar também valor econômico às produções gráficas. No presente estudo, o material de estudo compõe duas coleções fotográficas: uma com foco na arquitetura paulistana, e outra retratando personalidades do meio artístico. São acervos particulares cuja data e o processo de produção não são conhecidos. As análises de Fluorescência de Raios X por Dispersão de Energia (FRXDE) foram realizadas Laboratório de Espectroscopia e Espectrometria das Radiações (IPEN/CNEN-SP, Brasil), utilizando espectrômetro portátil de FRX da Amptek® com alvos de prata (Ag) e ouro (Au). Este instrumental é constituído por um detector de Silício Drift XR-100SDD (25 mm2 x 500 μm) com janela de Berílio (12,5 μm), acoplado a um pré-amplificador, um processador de pulso digital e multicanal. A condição de excitação foi estabelecida por 5 μA e 30 kV com tempo de contagem de 120 s. A análise elementar da coleção referente à arquitetura paulistana evidenciou o uso papeis com revestimento barita, muito utilizado por fotógrafos profissionais e amadores entre 1889-1930, evidenciam que essas fotos foram registradas entre o fim do século XIX e início do século XX. No que diz respeito ao acervo dos retratos, foi identificado o processo de cianotipia, evidenciado pela coloração azul das fotos (devido ao emprego sais de ferro como substância fotossensível), muito popular nas últimas décadas do século XIX [1,2]. Os resultados disponibilizados pela técnica de FRXDE permitiram situar a época e os processos fotográficos empregados. Essas informações contribuem para valorização desses acervos além de fornecer subsídios para o correto armazenamento e preservação.

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  • IPEN-DOC 26793

    BOIANI, N.F. ; SILVA, T.T.; BORRELY, S.I. . Toxicity assessment of caffeine, fluoxetine and their mixture on Daphnia similis: acute and cronic effects. In: SOCIETY OF ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY (SETAC) LATIN AMERICA BIENNIAL MEETING, 13th, September 15-18, 2019, Cartagena, Colombia. Abstract... Pensacola, FL, USA: Society of Environmental Toxicology and Chemistry, 2019. p. 109-109.

    Abstract: Emerging pollutants have already become a global problem, and they have been detected in dozens of countries, including Brazil. Even at very low concentrations, most of the emerging compounds are able to induce changes into biochemical system of aquatic organisms and they have also been reported as negative products to human health. Pharmaceuticals are considered as emerging contaminants detected in estuarine environment, in wastewater treatment facilities, lakes and rivers and even in sea waters. Generally the pharmaceuticals are detected among many other compounds into the ecosystem. The interaction of mixtures of contaminants is an important issue to be considered in monitoring programs as well as the negative effect to aquatic biota. The aim of the present paper was the assessment of toxic effects of pharmaceuticals exposed to Daphnia similis crustacean, individual and combined mixture of caffeine and fluoxetine. Caffeine (CAF) is a stimulant with cardiac, cerebral, diuretic and respiratory effects while Fluoxetine (FLX) is a selective serotonin re-uptake inhibitor, widely prescribed as antidepressant, (also known as Prozac®). The juveniles of D. similis were exposed separetaly to both caffeine (100mg/L) and to fluoxetine (20mg/L), and to a mixture of both (50mg/L caffeine and 20mg/L fluoxetine). Several experimental trials of acute immobilization test were performed. EC50 values ranged from 29,7 to 31 mg/L-1 for caffeine, and from 1.0 to 1.4 mg/L-1 for fluoxetine. Antagonistic effects of binary mixtures (EC50 = 15.2%) were observed. A chronic reproduction test was performed for the mixture of pharmaceuticals. We observed effects on D.similis survival, after 5 days. The mixture led to decrease of 72% in the reproduction, in maximum concentration (2.5% of the mixture – CAF 50ppm + FLX 20ppm). Concerning the importance of assessing toxicity the elected pharmaceuticals concentration were higher than those detected in the envinroment. These results may be incorporated into risk assessments analysis in order to protect sensitive aquatic ecosystems more effectively.

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  • IPEN-DOC 26792

    TOMINAGA, F. ; BOIANI, N.F. ; SANTANA, N.D.; BORRELY, S.I. . Acute toxicity assessment for binary and tertiary mixtures containing fluoxetine, propranolol and diclofenac to microcrustacean and zebrafish embryos. In: SOCIETY OF ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY (SETAC) LATIN AMERICA BIENNIAL MEETING, 13th, September 15-18, 2019, Cartagena, Colombia. Abstract... Pensacola, FL, USA: Society of Environmental Toxicology and Chemistry, 2019. p. 111-112.

    Abstract: Pharmaceuticals are essential for treatment and prevention of several diseases and for the maintenance of human and animal’s life quality. Due to the increasing use of pharmaceuticals worldwide, many actives substances are currently detected in μg.L-1 and ng.L-1 in different environmentals matrices such as surface water, ground water, soil and sediment. Many of these emerging pollutants are recalcitrant to biological treatment process in WWTPs and they may cause ecotoxicological effects on organisms and also possible to reach the human food chain. Pharmaceuticals are frequently detected as mixtures and may induce toxic effects to aquatic organisms, producing synergistic, additive or antagonistic toxic effects. Fluoxetine hydrochloride (FXT) is a selective serotonin reuptake inhibitor, prescribed as an antidepressant. Propranolol (PRP) is a beta-adrenergic blocker widely prescribed for the treatment of cardiovascular diseases and diclofenac sodium (DIC) is a non-steroidal anti-inflammatory drug, often recognized as the “world’s most popular pain killer”. These compounds are worldwide used for healthy treatment and also often detected in aquatic environments. This work aims to assess the toxicity of three pharmaceutical individually and in a mixture for both Daphnia similis and zebrafish embryos. The results of individual acute toxicity showed that the microcrustacean was more sensitive to FXT (EC50 = 1.08 mg/L), PRP (EC50 = 5.92 mg/L) and DIC (EC50 = 25.0 mg/L), respectively, while for zebrafish embryos, it was only calculated LC50 of 30.5 mg/L for DIC, after 48h exposure. Antagonistic effects of binary mixtures of FLX + PRP (EC50 = 9.38%) and FXT + DIC (EC50 = 24.2%) were observed to D. similis. For Danio rerio embryos, binary mixture of FLX + DIC (LC50 = 82.1%) presented antagonistic effects, while no acute toxicity was observed for the of FXT + PRP mixture. Tertiary mixture of the three compounds showed an antagonist effect (EC50 = 5.57%) for the microcrustacean and additive effect for zebrafish embryos (LC50 = 87.5%). In conclusion, most of the binary mixture resulted in antagonistic effects, in which the response of acute toxicity depended on the organism and type of pharmaceutical mixture. Therefore, it is necessary further studies to assess the toxicity of different mixtures.

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  • IPEN-DOC 26791

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

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

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  • IPEN-DOC 26790

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

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

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  • IPEN-DOC 26789

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

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

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  • IPEN-DOC 26788

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

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

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  • IPEN-DOC 26787

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

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

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  • IPEN-DOC 26786

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

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

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  • IPEN-DOC 26785

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

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

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  • IPEN-DOC 26784

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

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

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  • IPEN-DOC 26783

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

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

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  • IPEN-DOC 26782

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

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

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  • IPEN-DOC 26781

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

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

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  • IPEN-DOC 26780

    ZUFFI, ARMANDO V.F. ; ALMEIDA, ANDREIA A. ; VIEIRA JUNIOR, NILSON D. ; SAMAD, RICARDO E. . Development of glass nozzles for below threshold harmonics and high harmonic generation. In: FRONTIERS IN OPTICS; LASER SCIENCE CONFERENCE AND EXHIBITION, 15-19 September, 2019, Washington, DC, USA. Resumo expandido... Washington, DC, USA: OSA, 2019.

    Abstract: This work reports development of glass nozzles by ultrashort laser pulses machining for studies of harmonic generation in gases. Those nozzles generated odd harmonics (3rd up to 25th) in UV and VUV regions.

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  • IPEN-DOC 26779

    TOMINAGA, F.K. ; SILVA, T.T.; JESUS, J.M.S. de; BOIANI, N.F. ; TEIXEIRA, A.C.S.C.; BORRELY, S.I. . Effect of electron beam irradiation on mineralization and toxicity of aspirin. In: IBEROAMERICAN CONFERENCE ON ADVANCED OXIDATION TECHNOLOGIES, 4th; ISE SATELLITE STUDENT REGIONAL SYMPOSIUM ON ELECTROCHEMISTRY, 7th, November 18-22, 2019, Natal, RN. Resumo expandido... 2019. p. 1-3.

    Abstract: Electron Beam Irradiation (EBI) is an important technology for degradation, mineralization and detoxification of pollutants. In this work, total organic carbon (TOC) and toxicity was evaluated for aspirin after Electron Beam Irradiation at doses of 1.0, 2.5 and 5.0 kGy. Low mineralization was achieved at all applied doses. Toxicity increase and hydrogen peroxide formation was observed with the increase of absorbed dose. EBI can be an interesting alternative process applied as a pre-treatment for alternatives AOPs.

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  • IPEN-DOC 26778

    ROSSI, WAGNER de ; HERRERA, CRISTHIANO da C.; GOMES, ANTONIO A. ; BALDOCHI, SONIA L. . Femtosecond laser micromachining of microfluidic components in BK7 optical glass. In: EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES, September 1-5, 2019, Stockholm, Sweden. Abstract... Boutersem, Belgium: Federation of European Materials Societies, 2019. p. 898-898.

    Abstract: Introduction/Purpose The objective of this work was the development of micromachining with femtosecond laser in BK7 optical glass for the production of components of microfluidic devices. The aim was to produce microchannels, microvalves, micropumps, mixers and a localized heater, which can be arranged in any way to produce microfluidic devices on demand. Methods The structures were machined on the surface of BK7 glass plates, with the use of ultrashort laser pulses of a Ti:sapphire system on a high precision displacement stage and numerical control program. The first step was to obtain a set of process parameters suitable for efficient and accurate machining that would result in a smooth surface with no collateral damage to the neighboring region. Results Microvalves were machined with these optimized parameters, and when powered by pneumatic drive and managed by a dedicated software presented a flow control of less than 1 nl/s. These microvalves were used together to produce micrpumps to control flows in regions where external pressure can not be achieved. Mixers are also being developed for single phase systems and for biphasic systems. A machine vision system is being used to characterize both systems. Color analysis for single phase mixers and bubble analysis for biphasic ones. An innovative localized heating system was developed for temperature control in microreactors. For this, a tiny metal blade was textured with fs laser where light absorptive nanostructures were obtained. The slide was introduced into a microreator that had its temperature controlled through the focusing of an external source of light on its surface. With this, it was possible to control temperature above 100°C inside the microreator. Conclusions With the developed components, some microfluidic systems were built. In particular, a system for synthesis of NaYF4 nanocrystals and for ELISA assays will be presented.

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  • IPEN-DOC 26777

    FREIRE, L.O. ; ANDRADE, D.A. de . The four functions of elementary pipe design from constructal law. In: CONSTRUCTAL LAW AND SECOND LAW CONFERENCE, March 11-13, 2019, Porto Alegre, RS. Resumo expandido... 2019. p. 1-4.

    Abstract: Constructal law explains the sense of evolution (morphing to improve flows) of beings, but paradoxes do exist as not all vegetables have a tree form. Also, not all animals are optimized for displacement. This work aims at identification of the design functions or objectives that guide evolution under the overall statement of constructal law. This work adopted the system engineering technique of segregation between functions (abstract objectives) and solutions (physical entities). Further, this work introduced the assumptions of flow under external threats and pipes subject to leakages. Results showed that there are always elements doing four functions in pipe element: to reduce flow entropy, to protect flow channel, to retain flow content and to increase flow drive. Although the four functions are always present, natural systems typically privileges some functions over others, depending on environmental pressures. As a solution to improve flows, animal brains also fit in the model of four functions. Human mind seems to have groups of instincts associated to each of the four pipe design functions (fear, attachment, curiosity and greed). Finally, the four functions model unified physics and animal psychology.

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  • IPEN-DOC 26776

    GATTI, LUCIANA; MILLER, JOHN B.; BASSO, LUANA S.; DOMINGUES, LUCAS G. ; CASSOL, HENRIQUE L.G.; MARANI, LUCIANO; CORREIA, CAIO S. de C. ; IPIA, ALBER; ARAI, EGIDIO; TEJADA, GRACIELA; ARAGÃO, LUIZ E.O.C.; ANDERSON, LIANA O.; VON RANDOW, CELSO; GLOOR, MANUEL; PETERS, WOUTER; NEVES, RAIANE A.L.; CRISPIM, STEPHANE P.. Amazon carbon balance and its sensitivity to climate and human-driven changes. In: AGU FALL MEETING, December 9-13, 2019, San Francisco, CA, USA. Abstract... Washington, DC, USA: American Geophysical Union, 2019.

    Abstract: The Amazon accounts for 50% of Earth’s tropical rainforests hosting the largest live carbon pools in vegetation and soils (~200 PgC). The net carbon exchange between tropical land and the atmosphere is critically important, because the stability of carbon in forests and soils can be disrupted on short time-scales. The main processes releasing C to the atmosphere are deforestation, fires and changes in growing conditions due to increased temperatures and droughts. Such changes may thus cause feedbacks on global climate. In the last 40 years, the Amazon mean temperature has increased by 1.1ºC. Annual mean precipitation has also decreased by 51 mm during this same 40 year period. The precipitation reduction occurred mainly in the dry season, and the dry season has lengthened, exacerbating vegetation water stress with consequences for carbon balance. To better understand its C budget, starting in 2010 we established a regionally representative greenhouse gas monitoring program across Amazonia. The program aims to quantify gas concentrations (CO2, CH4, N2O, CO, and SF6) based on extensive collection of air from light aircraft vertical profiles. The atmosphere is profiled from the ground up to 4.5 km height at four sites along the main air-stream over the Amazon Basin on a twice-monthly basis. Here we will report what these new data tell us about the carbon balance and its controls from 2010-2017. During this period we performed 513 vertical profiles over four strategic regions that represent fluxes over much of Amazonia. The observed variability of carbon fluxes during these 8 years is correlated with climate-related (temperature, precipitation, soil water storage from GRACE satellite) and anthropogenic (fire counts) variables. The correlations were performed inside the upwind area for each profiling site. During our study period, the Amazon was a consistent source of 0.4 ± 0.2 PgC/year on average, extrapolating to the entire Amazon Basin area of 7.2 million km2. Fire emission is the main source of carbon to the atmosphere, which is not compensated by the C removal from old-growth Amazon forest. Moreover, the drought years of 2010, 2015 and 2016 are playing an outsized role in the eight-year mean. Removing those years from the mean, the net source is reduced from 0.4 ± 0.2 PgC/year to 0.2 ± 0.2 PgC/year.

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  • IPEN-DOC 26775

    MORAIS, FERNANDO; LANDULFO, EDUARDO ; ARTAXO, PAULO; FRANCO, MARCO A.; SCHAFER, JOEL; HOLBEN, BRENT. Long term characterization of brown carbon in Amazonia using AERONET and in situ measurements. In: AGU FALL MEETING, December 9-13, 2019, San Francisco, CA, USA. Abstract... Washington, DC, USA: American Geophysical Union, 2019.

    Abstract: Optical properties of aerosols in Amazonia have been measured over the last 19 years at several AERONET sites using CIMEL sunphotometers. Ground based measurements of aerosol absorption properties using AE33 Aethalometers were performed in several sites in Amazonia. Measurements were done in Central Amazonia (ATTO tower), as well as in Rio Branco, Cuiabá, Ji-Paraná, and Alta Floresta. The results show an important contribution to absorption by the brown carbon (BrC) component together with black carbon (BC). This behavior can be strongly observed at the wavelengths of 440nm and 470nm, for AERONET and AE33 measurements, respectively. Results from AERONET showed that, in sites dominated by biomass burning such as Alta Floresta, Rio Branco and Ji-Paraná, the BrC was about 20% of BC. In special, for the dry season of 2018 at Rio Branco, the BrC was about 9% of BC, with values of 3.28±3.45 µg m-3 and 0.34±0.58 µg m-3 for BC and BrC, respectively. The measured high variability in the ratio BrC/BC was due to different aging of biomass burning plumes that reached the site, some with high BC values of up to 24 µg m-3. On the other hand, in situ measurements at the ATTO Tower showed that the BrC component can account for 30% of total absorption. For the wet season of 2019, it was observed that BrC accounts for 28 % of BC, with mean values of BC and BrC of 0.23±0.16 µg m-3 and 0.054±0.075 µg m-3, respectively. The high variability in this case was due to plumes of African biomass burning that reached the site in different periods. For central Amazonia, ground based in situ measurements and AERONET agree quite well in the in situ BrC determination, showing a well-mixed atmosphere due to strong convection.

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  • IPEN-DOC 26774

    JEONG, DAUN; SECO, ROGER; EMMONS, LOUISA K.; SCHWANTES, REBECCA; LIU, YINGJUN; MCKINNEY, KARENA A.; MARTIN, SCOT T.; KEUTSCH, FRANK N.; GU, DASA; GUENTHER, ALEX B.; VEGA, OSCAR ; TOTA, JULIO; SOUZA, RODRIGO A.F. de; SPRINGSTON, STEPHEN R.; WATSON, THOMAS B.; KIM, SAEWUNG. Reconciling measured OH through box model simulations during GoAmazon2014/5. In: AGU FALL MEETING, December 9-13, 2019, San Francisco, CA, USA. Abstract... Washington, DC, USA: American Geophysical Union, 2019.

    Abstract: Hydroxyl radicals (OH) are important oxidants in the troposphere, controlling the lifetime of trace gases including methane, which is a greenhouse gas. The primary production of OH is from the photolysis of O3. OH levels can be further sustained through HOx-NOx recycling reactions. Volatile organic compounds (VOC) react with OH to produce organic peroxyl radicals (RO2), which can oxidize NO to NO2, leading to O3 production and subsequent re-generation of OH. However, in low NOx and high VOC environments, OH levels can be limited due to the production of stable peroxides from reactions between peroxy radicals. Therefore, conventional chemistry predict constrained OH levels in remote forest regions. Observations of OH carried out in forests, however, have consistently reported up to 10-fold higher than expected OH levels. In this study, we report OH observations by chemical ionization mass spectrometry (CIMS) conducted in a rainforest environment during the GoAmazon2014/5 campaign. The measurements used in this study, were during the wet season (IOP1), at the T3 site, which was ~ 60 km west of Manaus, Brazil. OH observations are compared to observation constrained box model simulations embedded with a near-explicit chemistry like MCM 3.3.1 (Master Chemical Mechanisms) and condensed mechanisms like RCIM (Reduced Caltech Isoprene Mechanism), CB05 (Carbon Bond Mechanism), CB6r2 (Carbon Bond 6 Mechanism), RACM2 (Regional Atmospheric Chemistry Mechanism), and MOZART_T1 (Model for Ozone and Related Chemical Tracers) that are used in global models.

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  • IPEN-DOC 26773

    CORREA, E.L. ; PEREIRA, L.F. ; FERREIRA, W.L. ; BOSCH-SANTOS, B. ; SCALISE, L. ; GONÇALVES, V. ; SANTOS, R. dos ; SCHELL, J.; CARBONARI, A.W. . Study of the local magnetics and electrics properties at Gd2Ti2O7 by PAC spectroscopy and ab initio calculations. In: JOINT MMM-INTERMAG CONFERENCE, January 14-18, 2019, Washington, DC, USA. Abstract... Melville, NY, USA; Piscataway, NJ, USA: AIP Publishing; IEEE Magnetics, 2019. p. 760-760.

    Abstract: Gd2Ti2O7 exhibits a complex magnetic behavior with a geometrically frustrated antiferromagnetic ordering below TN = 1.1 K and a second magnetic transition at 0.7 K. In the work here reported, perturbed angular correlation (PAC) technique was used in order to measure electric quadrupole hyperfine interactions at 111mCd probe nuclei on Ti sites. These experimental results along with those for magnetic hyperfine interactions at 155Gd previously reported from Mossbauer Effect spectroscopy were interpreted with electronic structure first-principles calculation. Single and doped-Cd cell simulations have been performed with potential linearized augmented plane waves methods and generalized gradient approximation from Perdew-Burke-Ernzerhorf embodied within the WIEN2k all-electron code. PAC measurements have exhibited 111mCd probes occupying two fraction sites characterized by well-defined quadrupole frequencies (as shown in the spin-rotation spectra in the figure) with almost the same values for the corresponding electric field gradient (efg), however, with slightly difference in the asymmetry parameters. Theoretical efg’s obtained for Cadmium atoms located at Gd or Ti sites of the pyrochlore structure indicate that both experimental hyperfine parameters corresponding to Cd at Titanium site.

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

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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 .

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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.