Reposiório IPEN: Recent submissions

  • IPEN-DOC 26926

    CAZULA, C.D. ; CAMPOS, M.P. ; MAZZILLI, B.P. . Calibração de detectores sólidos de traços nucleares do tipo CR-39 para medidas de Rn-222 no ar. Brazilian Journal of Radiation Sciences, v. 3, n. 1A, p. 1-8, 2015. DOI: 10.15392/bjrs.v3i1A.174

    Abstract: No método de detecção com detectores sólidos de traços nucleares, quando uma partícula pesada incide sobre a superfície do detector, provoca um desarranjo em sua estrutura molecular formando um traço. Uma das aplicações mais comuns desses detectores está na medição da concentração de Rn-222 no ar, um gás nobre radioativo, membro da série do U-238, emissor de partículas alfa e importante em estudos epidemiológicos para proteção dos indivíduos à radiação natural. Para determinar a concentração de Rn-222 no ar em um ambiente é necessário conhecer a densidade de traços (traços/cm2) na superfície do detector, o tempo de exposição e o fator de calibração. A determinação do fator calibração para os detectores CR-39 foi feita a partir da exposição destes a uma concentração conhecida de Rn-222. Para tanto, os detectores foram inseridos no interior de uma célula de Lucas adaptada e posteriormente expostos a uma concentração de Rn-222 de 15 kBq/m3, por meio do aparelho RN-150 da Pylon Eletronics Incorporation, que possui uma fonte de Ra-226 e libera concentrações conhecidas de Rn-222. Foram realizadas seis determinações do fator de calibração, o valor médio obtido foi de 0,0534 ± 0,0021 (traços/cm2 por Bq/m3 dia). Os resultados são compatíveis com os valores da literatura para o mesmo tipo de detector e apresentaram boa reprodutibilidade.

    Palavras-Chave: calibration; concentration ratio; experimental data; optical microscopy; particle tracks; radiation detectors; radiation sources; radon 222; radon 226

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  • IPEN-DOC 26925

    PIRES, JULIANA A. ; LIMA, DAMARIS C.; SILVA, LUCIA C.A.S.; ARTHUR, VALTER; HARDER, MARCIA N.C.. Efeitos da irradiação (Co60) nas propriedades físico-químicas de batata minimamente processada / Effects of irradiation (Co60) on the physical-chemical properties of minimally processed potato. Brazilian Journal of Food Research, v. 8, n. 1, p. 72-79, 2017. DOI: 10.3895/rebrapa.v8n1.3721

    Abstract: A batata (Solanum tuberosum L.) é um tubérculo que possui qualidades nutritivas e por adaptar-se facilmente a vários tipos de solo, seu consumo generalizou-se em todo o mundo. A irradiação nos últimos anos está sendo utilizada como alternativa no aumento de vida útil de vários alimentos, portanto esse trabalho objetivou avaliar o efeito da radiação gama na conservação de batatas-inglesas minimamente processadas. As batatas foram higienizadas, e minimamente processadas e embaladas a vácuo e posteriormente irradiadas em dose de 0; 1; 2; 3kGy. Foram realizadas análises físico-químicas de pH, acidez, sólidos solúveis e firmeza. Como resultado obteve-se os melhores resultados nas amostras irradiadas à 1kGy, pois apresentou valores próximos aos da testemunha nos parâmetros avaliados, além do maior valor de firmeza, características estas desejáveis em produtos minimamente processados. Conclui-se que o efeito da radiação na dose de 1kGy foi adequado no tratamento de batatas-inglesas minimamente processadas.

    Palavras-Chave: potatoes; physical properties; chemical properties; gamma radiation; food processing; cobalt 60; irradiation; radiation effects; brazil

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  • IPEN-DOC 26924

    MACHI, ANDRE R. ; HARDER, MARCIA N.C.; ARTHUR, PAULA B. ; FRANCO, SUELY S.H.; ARTHUR, VALTER . Ionizing radiation and the influence of package to control of Sitophilus oryzae in rice. Australian Journal of Basic and Applied Sciences, v. 11, n. 15, p. 71-75, 2017. DOI: 10.22587/ajbas.2017.11.15.10

    Abstract: Objective: This study aimed to use the gamma radiation from Cobalt-60 to control of Sitophilus oryzae in package with previously infested rice and artificial reinfestation. Material and Methods: In the research, 3 types of sample were used: 2 commercial rice packages and 1 in crystal sugar packages. The samples were irradiated with a dose of 1.0kGy to promote disinfestations under a dose rate of 0.560 Gy/h. After 60 days were counted the number of live and dead insects in each package. Results: We concluded that the package containing holes for gases exchange from inside to outside of the package showed easily penetration of insects, while the two packages without holes prevented the reinfestation of insects. Conclusion: The dose of 1.0 kGy was sufficient to do the disinfestations of rice.

    Palavras-Chave: irradiation; ionizing radiations; packaging; cobalt 60; rice; pest control; insects; storage life; gamma radiation; dose rates; disinfestation

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  • IPEN-DOC 26923

    VECCHIO, DANIELA; GUPTA, ASHEESH; HUANG, LIYI; LANDI, GIACOMO; AVCI, PINAR; RODAS, ANDREA ; HAMBLIN, MICHAEL R.. Bacterial photodynamic inactivation mediated by methylene blue and red light is enhanced by synergistic effect of potassium iodide. Antimicrobial Agents and Chemotherapy, v. 59, n. 9, p. 5203-5212, 2015. DOI: 10.1128/AAC.00019-15

    Abstract: The inexorable increase of antibiotic resistance occurring in different bacterial species is increasing the interest in developing new antimicrobial treatments that will be equally effective against multidrug-resistant strains and will not themselves induce resistance. One of these alternatives may be photodynamic inactivation (PDI), which uses a combination of nontoxic dyes, called photosensitizers (PS), excited by harmless visible light to generate reactive oxygen species (ROS) by type 1 (radical) and type 2 (singlet oxygen) pathways. In this study, we asked whether it was possible to improve the efficacy of PDI in vitro and in vivo by addition of the inert salt potassium iodide (KI) to a commonly investigated PS, the phenothiazinium dye methylene blue (MB). By adding KI, we observed a consistent increase of red light-mediated bacterial killing of Gram-positive and Gram-negative species in vitro and in vivo. In vivo, we also observed less bacterial recurrence in wounds in the days posttreatment. The mechanism of action is probably due to formation of reactive iodine species that are produced quickly with a short lifetime. This finding may have a relevant clinical impact by reducing the risk of amputation and, in some cases, the risk of death, leading to improvement in the care of patients affected by localized infections.

    Palavras-Chave: bacteria; inactivation; photosensitivity; methylene blue; potassium iodides; in vivo; in vitro; antibiotics; drugs; light sources; therapy; reagents

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  • IPEN-DOC 26922

    KIBRIT, EDUARDO ; AQUINO, AFONSO R. de ; MELLO, ADRIANA M. de; NASCIMENTO, PAULO T. de S.. Sustainable operations in nuclear research reactors: a bibliographical study. atw - International Journal for Nuclear Power, v. 62, n. 10, p. 589-596, 2017.

    Palavras-Chave: bibliographies; radioactive waste management; reactor operation; recycling; research reactors; sustainability; document types; management; operation; reactor life cycle; reactors; research and test reactors; waste management

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  • IPEN-DOC 26921

    KONIGAME, VIVIAN C.; CONTI, THADEU das N. . Estudo do reator nuclear de 4ª geração “Very High Temperature Reactor” – VHTR / Study of nuclear reactor of 4th generation “Very High Temperature Reactor” – VHTR. Revista Engenharia e Tecnologia Aplicada - UNG, v. 1, n. 1, p. 47-68, 2017.

    Abstract: Como resultado do crescimento populacional e desenvolvimento da economia há uma demanda maior por energia, sendo necessário diversificar suas fontes de geração, sem causar aumento dos impactos negativos ao meio ambiente. Atualmente, há diversas fontes de geração de energia (combustíveis fósseis, renováveis, nuclear etc). A energia gerada por reatores nucleares é segura, e apresenta vantagens econômicas e ambientais e, por isso, está sendo considerada uma opção viável para geração de energia no futuro. Há diversas gerações de sistemas de reatores nucleares, sendo que no presente trabalho será estudado o reator de geração-IV, “Very-High-Temperature Reactor” (VHTR). O VHTR é um reator térmico, moderado a grafite, refrigerado a hélio, e com um ciclo aberto para o urânio. É seguro e eficiente na cogeração de hidrogênio e eletricidade, e pode reduzir a dependência das reservas de combustíveis fósseis, a emissão de gases nocivos ao meio ambiente e a poluição.

    Palavras-Chave: reactors; nuclear energy; temperature range 1000-4000 k; hydrogen; thermal reactors; nuclear fuels; environmental impacts; energy source development; carbon

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  • IPEN-DOC 26920

    CAVINATO, C.C. ; ANDRADE, D.A. ; DIZ, M.D.P.E.; SABUNDJIAN, G. . Levantamento bibliográfico sobre metodologias para elaboração de um banco de dados da saúde da população em casos de ocorrências de câncer. Brazilian Journal of Radiation Sciences, v. 3, n. 1A, p. 1-14, 2015. DOI: 10.15392/bjrs.v3i1A.79

    Abstract: As fontes alternativas de energia, incluindo a nuclear, apresentam vantagens com relação às externalidades, as quais podem ser identificadas e relacionadas com o termo, custo ambiental. Este termo, por sua vez, é uma externalidade negativa, que de alguma forma prejudica o meio ambiente e é convertida em termos econômicos, para então poder ser comparada aos demais custos de uma ação e/ou empreendimento. A fim de efetuar os cálculos em questão, são utilizados alguns softwares específicos, os quais possibilitam a conversão dos danos em termos econômicos e a inclusão do custo ambiental na análise de custo de determinado projeto. Uma das dificuldades encontradas na utilização destes softwares tem sido com relação a alguns dados de entrada, como por exemplo, os relativos à saúde da população em torno da instalação nuclear, que são muito deficientes. O objetivo deste trabalho é fazer um levantamento teórico correspondente às metodologias existentes e utilizadas para a elaboração de banco de dados de saúde pública no Brasil. A partir das metodologias encontradas para a formação deste tipo de banco de dados, posteriormente será desenvolvida uma metodologia focando na saúde (câncer fatal e não fatal) da população circunvizinha a uma instalação nuclear, para fins de cálculo do custo ambiental da mesma. Essa será aplicada ao público interno do Instituto de Pesquisas Energéticas e Nucleares (IPEN), como um pré-teste, para aquisição das informações de saúde desejadas.

    Palavras-Chave: computer codes; data acquisition; information; neoplasms; nuclear facilities; public health; brazilian organizations; data processing; diseases; national organizations; processing; brazilian cnen

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  • IPEN-DOC 26919

    EGGERT, B.G.F.; TEIXEIRA, C.S.; LOPES, L.U. ; WENDHAUSEN, P.A.P.. Feasibility of Nd substitution in (La, Nd)(Fe, Si)13 magnetocaloric compound obtained by the reduction-diffusion process. IEEE Transactions on Magnetics, v. 52, n. 5, 2016. DOI: 10.1109/TMAG.2015.2512502

    Abstract: Quaternary magnetocaloric compound La1−xNdxFe11.3Si1.7 was synthesized via the so-called reduction–diffusion (RD) process. The RD process was carried out at 1423 K, using Ca as the reducing agent and La and Nd oxides as the precursors to form, together with iron and silicon powder, the desired cubic NaZn13-type structure. The main purpose was to study the interchange of La and Nd in terms of process yield, crystal structure parameters and typical magnetic transition temperature [Curie temperature (Tc)] associated with the magnetocaloric effect. Microstructural characterization by scanning electron microscopy associated with microprobe energy dispersive spectroscopy and backscattered electron imaging was used to identify morphology and particle size of reaction products, as well as the extent of diffusion reactions. Structural characterization results obtained by X-ray diffraction technique associated with Rietveld refinements show the possibility to obtain almost single-phase La1−xNdxFe11.3Si1.7, for which x was varied from 0 to 0.5, with reminiscent α-iron phase below 10 wt%. Moreover, the Tc of all obtained alloys were inferred from differential scanning calorimetry curves, showing that Nd is an effective alloying element to tune the working temperature in the near-room-temperature magnetic refrigeration.

    Palavras-Chave: neodymium compounds; feasibility studies; intermetallic compounds; magnetic properties; reduction; microstructure; x-ray diffraction; magnetic fields; regenerators; magnetic properties

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  • IPEN-DOC 26918

    FUNGARO, DENISE A. . Estabilização de solo contaminado com zinco usando zeólitas sintetizadas a partir de cinzas de carvão. Revista Água e Meio Ambiente Subterrâneo, v. 7, n. 43, p. 28-28, 2015.

    Palavras-Chave: zeolites; coal; ashes; soils; contamination; stabilization

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  • IPEN-DOC 26917

    ARTHUR, VALTER ; GUEDES, ELIANE D.F. da S.; SILVA, LUCIA C.A.S.; PIRES, JULIANA A. ; HARDER, MARCIA N.C.; FRANCO, SUELY S.H. ; ARTHUR, PAULA B. ; FRANCO, CAMILO F. de O.; CAZE FILHO, JORGE. Efeitos da radiação gama nas características físico-químicas do arroz pré-cozido / Effects of gamma irradiation on the physicochemical characteristics of pre-cooked rice. Revista Tecnologia & Ciência Agropecuária, v. 10, n. 6, p. 83-86, 2016.

    Abstract: A pesquisa teve como objetivo avaliar os efeitos da radiação gama nas características físico-químicas do arroz pré-cozido como um método de conservação. A pesquisa foi realizada no laboratório de Radiobiologia e Ambiente do Centro de Energia Nuclear na Agricultura –CENA/USP, Piracicaba, SP., Brasil.As amostras foram irradiadas com doses de:0(controle); 1,0; 2,0; e 3,0 kGy, em um irradiador de Cobalto-60, tipo Gammacell-220, sob uma taxa de dose de 0,256 kGy/hora. Após a irradiação foram realizadas análises físicas químicas das amostras irradiadas e do controle. Para a analise dos resultados foi utilizado teste de Tukey (p ≤ 0,05) para verificar as diferenças estatísticas entre os tratamentos. Pelos resultados concluiu-se que o processo de irradiação na dose de 3 kGy pode ser utilizado na conservação das propriedades do arroz pré-cozido.

    Palavras-Chave: gamma radiation; cereals; rice; food processing; qualitative chemical analysis; cobalt 60; gravimetric analysis; irradiation; gamma sources

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  • IPEN-DOC 26916

    MONTEIRO, LUCILENA R. ; PORFIRIO, DARILENA M.; VILLA, SABRINA M. ; MARQUES, JOYCE R. ; FAUSTINO, MAINARA G. ; COTRIM, MARYCEL E.B. ; PIRES, MARIA A.F. . Implantação de controles de qualidade internos e externos em laboratórios de ensaios químicos. Jornal da Metrologia, 2015.

    Palavras-Chave: quality control; materials testing; testing; quality assurance; chromatography; anions; abundance; chemical analysis; chemical properties

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  • IPEN-DOC 26915

    MAZIERO, JOANA da S. ; ROGERO, SIZUE O. ; ALEMANY, ADAIR. Estudo ecotoxicológico da nanopartícula de prata em Daphnia similis / Ecotoxicological study of silver nanoparticle on Daphnia similis. Journal of the Health Sciences Institute - Revista do Instituto de Ciências da Saúde, v. 34, n. 3, p. 133-139, 2016.

    Abstract: Objetivo –Verificar a toxicidade da NPAg em organismos aquáticos por meio do ensaio de ecotoxicidade aguda. O aumento na produção e utilização das nanopartículas de prata (NPAg) em diversas áreas, tem provocado preocupação quanto aos impactos e riscos potenciais que estas podem causar ao meio ambiente. Métodos – O teste de ecotoxicidade aguda foi realizado seguindo a Norma Brasileira ABNT NBR 12713, utilizando como organismo-teste a Daphnia similis. A exposição dos organismos ocorreu em cinco concentrações de NPAg, durante 48 horas. O resultado de CE50, concentração do agente tóxico que causa imobilidade a 50% dos organismos expostos, da NPAg foi obtida pelo método estatístico de Trimmed Spearman-Karber. Resultados – A média da CE50 da NPAg obtidas nos três ensaios realizados foi de 4,70 μg L–1. Conclusão – De acordo com os resultados obtidos, a NPAg causou imobilidade a 50% dos organismos expostos na concentração de 4,70 μg L–1. Estudos devem ser continuados para melhor esclarecimento dos impactos no meio ambiente aquático.

    Palavras-Chave: aquatic ecosystems; toxicity; silver; nanoparticles; metals; daphnia; aquatic organisms; crustaceans; chemical analysis; physical chemistry; toxic materials

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  • IPEN-DOC 26914

    SOUZA, C.D. de ; ROSTELATO, M.C.M. ; CARDOSO, R.M.; ARAKI, K.; MOURA, J. . New methodology for binding Iodine-125 onto silver for brachytherapy sources manufacture. Medical Physics, v. 44, n. 6, p. 2828-2828, 2017. DOI: 10.1002/mp.12304

    Abstract: Purpose: Cancer is a major health care problem in Brazil and the world. The Brazil’s National Institute for Cancer estimates around 60,000 new prostate cancer cases for 2017. We are assembling a laboratory for production of iodine-125 sources used in prostate brachytherapy in Brazil, since the imported treatment is extremely expensive, thus only available in the private healthcare sector. There are several challenges when developing a laboratory to produce radioactive sources. From choosing a prototype to radiation safety, the task is enormous. The whole production line is full of new process and innovations. Among those, a new chemical reaction that deposit iodine-125 onto silver (core) was developed. This paper presents a new reaction for binding iodine-125 into a silver core. The fixation percentage was calculated by measuring the activity in an ionization chamber. This methodology will be implemented at the iodine-125 sources manufacture laboratory. Methods: Silver cores are washed with an etching solution (100% sulfuric acid) for 5 minutes with sonication. The cores were then placed in sodium sulfate for at least 3 days. They went from a silver matte to a black color. The reaction was allowed to proceed overnight. Each core was individually measured. Results: The yield was 69.2% 7.1%. Considering the silver attenuation is around 20% the results were consider satisfactory. Conclusion: By maximize the reaction yield, we will be able to generate a less costly product that will be available through our public healthcare.

    Palavras-Chave: brachytherapy; iodine 125; silver; neoplasms; therapy

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  • IPEN-DOC 26913

    RODRIGUES, B.T. ; ROSTELATO, M.C.M. ; SOUZA, C.D. de ; ZEITUNI, C. ; MOURA, E.S. de; SOUZA, D.B. de ; TOZETTI, C.; RODRIGUES, B. . New core configuration for producing Iodine 125 seeds. Medical Physics, v. 44, n. 6, p. 2828-2829, 2017. DOI: 10.1002/mp.12304

    Abstract: Purpose: Cancer is one of the most complex public health problems. Prostate cancer is the second most common among men. In prostate brachytherapy use Iodine-125, which is fixated on a silver substrate, then inserted and sealed in a titanium capsule. This work proposes a new source configuration using epoxy resin substrate. Methods: Comparation and analysis methods were used to define the methodology for combining iodine-125 in polymers. The parameters were immersion time, reaction type, concentration of the adsorption solution, specific activity of the radioactive solution, need for carrier and chemical form of radioactive iodine. Results: The methodology developed with an epoxy resin was very good. The final radioactive intake on the resin was higher than 80%. The immobilization of the radioactive solution occurred in the matrix, without any loss or deposition of undesirable materials on its surface, as evidenced by the smear test. The material maintains its integrity when autoclaved at 140 °C. The curing process of the resin was 40 minutes. With the value of the initial activity of the Iodine solution by mass (774.2 lCi/g), it was possible to calculate the immobilization efficiency Average of 680 lCi/g. The immersion test in distilled water at room temperature did not exceed the limit allowed by ISO 9978, which is 5 nCi (185 Bq), proof of no leakage. In a computational simulation by the Monte Carlo Method, PENELOPE, the simulations were consistent with the values adopted by the literature for the GE Healthcare model 6711, which shows the value of the dose rate constant as 0, 965 cGy.U-1.h-1. Conclusion: The effective method for combining iodine-125 in epoxy resin was determinated. The major advantage was the high efficiency percentage fixation, around 82,1 3,2%, and the simplicity and safety of the process.

    Palavras-Chave: neoplasms; prostate; iodine 125; polymers; epoxides; resins

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  • IPEN-DOC 26912

    RODRIGUES, B.T. ; SOUZA, P.D. de ; SOUZA, C.D. de ; ROSTELATO, M.C.M. ; ZEITUNI, C. ; NOGUEIRA, B.R. ; MARQUES, J. de O. ; SOUZA, A.S. de . Methodology for in vivo dosimetry using TLD-100 for radiotherapic treatment. Medical Physics, v. 44, n. 6, p. 2898-2899, 2017. DOI: 10.1002/mp.12304

    Abstract: Cancer is a public health problem that affects approximately 27 million people worldwide. The most common type in Brazil among men is prostate cancer with 61 thousand cases. There are two forms of radiotherapy treatments that can be used: teletherapy and brachytherapy. Before starting the teletherapy treatment, a planning is done that makes the acquisition of the anatomical information of the patient to then classify the areas of interest. Dosimetry is performed as a quality control to ensure that the calculated dose is equal to that received by the patient. In vivo dosimetry acts as an independent measurement and this work aims at comparing the dosimetry performed using thermoluminescent dosimeters (LiF: Mg, Ti - TLD - 100) with dose values calculated in the planning system (TPS). Methods: All dosimeters were prepared to be used in an anthropomorphic phantom. A selection of dosimeters, 50 micro TLD’s, selected after heat treatment, were then irradiated and a reading was made. A case planned by TPS was selected and compared the dosimetry performed in an anthropomorphic phantom for the same case. Results: All values obtained were within the deviation ( 5%) allowed by the protocol. The results of this work will help to implement a new quality program in the Radiotherapy Service at Hospital das Cl ınicas de S~ao Paulo. Conclusion: The accurate dosimeter selection provided a feasible and reliable evaluation that enabled the comparison.

    Palavras-Chave: neoplasms; prostate; radiotherapy; brachytherapy; thermoluminescent dosimetry

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  • IPEN-DOC 26911

    SOUZA, D.B. de ; ROSTELATO, M.C.M. ; VICENTE, R. ; ZEITUNI, C. ; SOUZA, C.D. de ; RODRIGUES, B.T. ; MARQUES, J. de O. ; CARVALHO, V. ; BARBOSA, N. . Measurement of Iodine-125 radioactive solid waste derived from sources production laboratory for brachytherapy. Medical Physics, v. 44, n. 6, p. 2974-2975, 2017. DOI: 10.1002/mp.12304

    Abstract: Purpose: This study aims to present a solid waste management plan for the laboratory of radioactive sources production (LPFR), iodine-125 brachytherapy seeds, located at the Energy and Nuclear Research Institute (IPEN). After the implementation, it is expected to meet a demand of 8000 seeds per month. Methods: Waste from the production of Iodine-125 sources is classified as “Very Low Level Waste Disposal” (T1/2 ≤ 100 days) in the IAEA regulations. Despite that, they have levels of activity above the limits established in standard (CNEN 8.01) needing adequate management in order to guarantee the safety of the installation, operators and environment. The solid waste is generated in Glove box 1, were the fixation reaction (iodine-125 – core) takes place. The wastes from this production are absorbent papers and filters used in surface and air decontamination processes; glass vials, syringes and needles, used in the fixation reaction. Measures of mass, volume and values of activities generated over 5 years of production were performed for each glove box by estimating different scenarios throughout production (supplier switching, variation in activity by radioactive source, etc.). The concentration of activity was also determined in order to meet the criteria established in the standard for safe release of the waste. Results: The final volumes and activities calculated indicated that the laboratory has enough space for temporary storage until the release to the environment (thus not requiring treatment, transport, and another place for management). The data collected proved that a secure management system for radioactive waste within the facility is possible. Conclusion: The management proposed by this work was able to safely contemplate all stages of waste management. This data is indispensable for the construction and licensing of the laboratory.

    Palavras-Chave: radioactive waste management; solid wastes; iodine 125; brachytherapy; regulations; waste disposal

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  • IPEN-DOC 26910

    BAPTISTA, T. ; ROSTELATO, M.C.M. ; ZEITUNI, C. ; PERINI, E.A. ; SOUZA, C.D. de ; MARQUES, J. de O. ; NOGUEIRA, B.R. ; ANGELOCCI, L.V. . Efficiancy of hydrogen peroxide for cleaning production areas and equipments in the Laboratory for Brachyterapy Sources Production. Medical Physics, v. 44, n. 6, p. 2828-2828, 2017. DOI: 10.1002/mp.12304

    Abstract: Purpose: A great challenge in the brachytherapy sources production is to fulfill the Good Manufacturing Practices (GMPs) requirements, involving the process validation and of all supporting activities such as cleaning and sanitization. The increasingly strict requirements for quality assurance system, with several norms, normative resolutions and rules that must follow both medical products and radiochemical requirements, has led to a constant validation concerns. The main goal of GMP is to reduce inherent risks such as product contamination with microorganisms and cross-contamination. Methods: In the Laboratory for Brachytherapy Sources Production it was established a cleaning program for cleanrooms and hot cells using a hydrogen peroxide solution (6%). This work aims to assess the effectiveness of this cleaning agent in reducing and/or eliminating microbial load into the cleanrooms and equipments to acceptable levels in accordance with the current legislation. Results: The analysis was conducted using the results of the environmental monitoring program with settling contact plates in cleanrooms after the cleaning procedures. Furthermore, it was possible to evaluate the action of the sanitizing agent on the microbial population at the equipment and cleanrooms’ surfaces. It was also evaluated the best way to accomplish the cleaning program considering the dosimetry factor in each production process, hence the importance of radiological contamination. All the following environmental monitoring procedures presented satisfactory results, showing that the cleaning procedures was able to reduce and maintain the acceptable levels of viable and non-viable particles for the cleanroom classification (ISO 5 and ISO 7). The cleaning process with this sanitizer (hydrogen peroxide) can be performed quickly right before the production; allowing the production of brachytherapy sources without after use residues. Conclusion: This data will help the production of a clean and reliable product.

    Palavras-Chave: radiopharmaceutical; isotope production; cleaning; equipment; clean rooms; pollution sources; contamination; hydrogen peroxide

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  • IPEN-DOC 26909

    RIBEIRO, ANDREZA P. ; FIGUEIREDO, ANA M.G. ; SANTOS, JOSE O. dos; FERREIRA, PAULO A. de L.; GRAUDENZ, GUSTAVO S.; RUIZ, MAURO S.; MAHIQUES, MICHEL M. de; FIGUEIRA, RUBENS C.L.; WASSERMAN, JULIO C. de F.A.. Effects of contamination with toxic metals on the environmental quality of Sepetiba Bay (SE Brazil): The case of Ingá Company. Management of Environmental Quality, v. 26, n. 4, p. 538-551, 2015. DOI: 10.1108/MEQ-06-2013-0074

    Abstract: Purpose – The purpose of this paper is to address the case of toxic metal contamination of Sepetiba Bay caused by the Ingá Company. The paper reviews the history of the contamination and discusses the current presence of metals in the bay sediments, demonstrating that the toxic metals are clearly enriched. Sepetiba Bay is prone to significant dredging activities that make metals available in the food chain, affecting human populations, mainly fishermen communities. Design/methodology/approach – The study presents the case of the Ingá Company based on international literature and data provided by previous studies. Findings – Through the analysis and compilation of diverse data from the literature, this study demonstrates that the Ingá Company is a major source of Cd, Pb and Zn due to its calamine processing activities used to obtain high purity Zn. Originality/value – This study highlights important research to complete the historical scenario of heavy metal contamination of the Sepetiba Bay by Ingá Company. The results indicate that the contaminants from the Ingá Company can indeed be traced in the sediments of Sepetiba Bay. These data have the utmost value for the environmental management of this coastal system, because such high concentrations of toxic metals in marine sediments have serious implications for the environmental quality of the bay and may negatively affect biota and human health. Therefore, this study suggests that it is now necessary to monitor this region for contamination continuously.

    Palavras-Chave: pollution; water pollution monitors; concentration ratio; environmental impacts; metals; toxic materials; toxicity; environmental impacts; bays; brazil; environmental quality; water quality

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  • IPEN-DOC 26908

    SILVA, L.F.F.L. da ; ZAMBONI, C.B. ; BAHOVSCHI, V. ; METAIRON, S. ; SUZUKI, M.F. ; SANTANNA, O.A.; RIZZUTTO, M.A.. Determination of inorganic elements in blood of mice immunized with Bothrops Snake venom using XRF and NAA. Journal of Physics: Conference Series, v. 630, p. 1-6, 2015. DOI: 10.1088/1742-6596/630/1/012005

    Abstract: In this work, mice genetically modified [HIII line] were immunized against different Bothrops snake venoms to produce anti-Bothrops serum (antivenom). The Neutron Activation Analysis (NAA) and Energy Dispersive X-Ray Fluorescence (EDXRF) techniques were used to evaluate Ca and Fe concentrations in blood of these immunized mice in order to establish a potential correlation between both phenotypes: antibody response and blood constituents after Bothrops venom administration. The results were compared with the control group (mice not immunized) and with human being estimative. These data are important for clinical screening of patients submitted to immunological therapy as well as the understanding of the envenoming mechanisms.

    Palavras-Chave: antibodies; blood; calcium; comparative evaluations; concentration ratio; correlations; fluorescence; iron; mice; neutron activation analysis; patients; phenotype; screening; snakes; therapy; venoms; x radiation; x-ray fluorescence analysis

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  • IPEN-DOC 26907

    MIRANDA, LEILA F. de; GOULART, LEID J.P.; SILVA, LEONARDO G. de A. e ; DONADON, ALEXANDRE C.; YAMASAKI, FABIO Y.; MUNHOZ JUNIOR, ANTONIO H.. Characterization of polystyrene nanocomposites containing nanoparticles of pseudoboehmite obtained by sol-gel process. Journal of Nano Research, v. 47, p. 96-105, 2017. DOI: 10.4028/www.scientific.net/JNanoR.47.96

    Abstract: Polymeric nanocomposites are hybrid materials in which inorganic substances of nanometric dimensions are dispersed in a polymeric matrix. These inorganic substances have high surface area allowing a better interaction with the polymeric matrix and consequently promote changes in the physical properties of the final composite with small additions of the same. The preparation of nanocomposites with polymer matrix allows in many cases to find a relationship between a low cost due to the use of lower amount of charge, reaching high level of performance. In this work, it was obtained polystyrene nanocomposites with pseudoboehmite synthesized by the solgel process with different concentrations of pseudoboehmite using and not using octadecylamine as a coupling agent. The nanocomposites were prepared by the melt intercalation technique. The pseudoboehmite nanoparticles were characterized by X-ray diffraction, scanning electron microscopy, differential thermal analysis and thermo gravimetric analysis. The nanocomposites were characterized by differential thermal analysis, thermogravimetric analysis, heat deflection temperature, Vicat softening point, mechanical and rheological tests. The results showed an increase in the thermal properties, hardness and tensile strength values and decrease in the melt index, impact resistance and tensile elongation, showing the interaction of the filler with the polymer matrix. Although in the samples with the presence of octadecylamine the data shows that the thermomechanical properties practically do not vary in relation with the samples without octadecylamine.

    Palavras-Chave: polystyrene; nanocomposites; polymerization; sol-gel process; aluminium oxides; amines; thermal gravimetric analysis; synthesis

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  • IPEN-DOC 26906

    ISAAC, CESAR; MATHOR, MONICA B. ; TEODORO, WALCI; CARVALHO, VIVIANE F. de; GEMPERLI, ROLF; PAGGIARO, ANDRE de O.. Avaliação microscópica de técnicas de desepitelização de membranas amnióticas gliceroladas / Microscopic evaluation of deepithelization techniques of glycerolated amniotic membrane. Revista Saúde - UNG, v. 10, n. 3-4, p. 22-33, 2016.

    Abstract: Introdução: A membrana amniótica (MA) é considerada um biomaterial com propriedades biológicas benéficas ao processo de reparação tecidual servindo também como substrato para o cultivo de células epiteliais. Objetivo: estabelecer um método de desepitelização amniótica que preserve a membrana basal. Método: Foram testados 7 tipos diferentes de desepitelização enzimática de membranas amnióticas gliceroladas, avaliando-se cada um por microscopia óptica e posteriormente, por microscopia eletrônica. Resultado: A exposição das membranas à Tripsina 0,05%/EDTA 0,02% por 20 minutos permitiu a completa retirada epitelial com a menor delaminação quando comparado aos outros métodos testados. A microscopia eletrônica evidenciou que após desepitelizacão com Tripsina 0,05%/EDTA 0,02% por 20 minutos a membrana basal permanecia íntegra. Conclusão: Tripsina 0,05%/EDTA 0,02% por 20 minutos permite completa desepitelização das MAs com preservação da membrana basal.

    Palavras-Chave: fetal membranes; embryonic cells; cell membranes; cell cultures; glycerol; epithelium; basements; evaluation; optical microscopy

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  • IPEN-DOC 26905

    GALIZONI, BRENO B.; COUTO, ANTONIO A. ; REIS, DANIELI A.P.. Heat treatments effects on nickeI-based superalloy Inconel 713C. Defect and Diffusion Forum, v. 390, p. 32-40, 2019. DOI: 10.4028/www.scientific.net/DDF.390.32

    Abstract: The purpose of this work is to study the effect of heat treatments on the microstructure of the nickel-based superalloy Inconel 713C. Three different conditions were studied and the results compared: (1) as cast; (2) solution treatment (1,179°C/2h) and (3) stabilizing treatment (1,179°C/2h plus 926°C/16h). Inconel 713C is normally used in the as-cast condition, an improvement in the 980°C stress-rupture life is often obtained by a solution heat treatment. However, the material in this condition tested under high stress at 730°C shows a marked decreased in rupture life and ductility [1]. The mechanical resistance in creep increases in Inconel 713C by precipitation hardening phase, such γ’ (Ni3Al) formed during the heat treatments [2]. The characterization techniques used was: chemical analysis, hardness test, X-ray diffraction, optical microscope and scanning electron microscopy (SEM), EDS analyzes and thermocalculation. The heat treatments modified the dendritic structure, reducing the acicularity. The SEM and EDS analysis illustrated the γ, γ’ and carbides. The matrix phase (γ), has in its constitution the precipitation of the γ’ phase, in a cubic form, and in some regions, veins of carbides were modified with the heat treatments.

    Palavras-Chave: heat treatments; alloys; inconel 713c; microstructure; nickel base alloys; chemical analysis; mechanical properties

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  • IPEN-DOC 26904

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

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

    Palavras-Chave: iron base alloys; accident-tolerant nuclear fuels; fuel-cladding interactions

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  • IPEN-DOC 26903

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

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

    Palavras-Chave: nuclear power; public information; knowledge base; public opinion; radiation protection

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  • IPEN-DOC 26902

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

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

    Palavras-Chave: corrosion resistance; adhesion; aluminium alloys; silicon alloys; steels

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  • IPEN-DOC 26901

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

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

    Palavras-Chave: adhesives; urethane; shear; composite materials; joints

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  • IPEN-DOC 26900

    BELCHIOR JUNIOR, A. ; SANTOS, A.A.C. dos; FREITAS, R.L.; SOARES, H.V.; JUNQUEIRA, F.C. ; MANTECON, J.G. ; MATTAR NETO, M. ; MENZEL, S.C. ; TORRES, W.M. ; UMBEHAUN, P.E. . Analytical and experimental analysis on safety related aspects of the RMB research reactor. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: ADDRESSING CHALLENGES AND OPPORTUNITIES TO ENSURE EFFECTIVENESS AND SUSTAINABILITY, November 25-29, 2019, Buenos Aires, Argentina. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2020.

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

    Palavras-Chave: computerized simulation; reactor design; reactor operation; reactor safety; rmb reactor; safety analysis; spent fuels; stratification; thermal hydraulics; two-phase flow

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  • IPEN-DOC 26899

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

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

    Palavras-Chave: lanthanum; boron; borides; steels

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  • IPEN-DOC 26898

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

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

    Palavras-Chave: bacteria; yeasts; ionizing radiations; gamma radiation; fluorescence

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  • IPEN-DOC 26897

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

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

    Palavras-Chave: disinfestation; quarantine; therapy; storage; insects

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  • IPEN-DOC 26896

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

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

    Palavras-Chave: food processing; irradiation; chromatography; flowers

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  • IPEN-DOC 26895

    GIANNONI, JULIANA A.; FIORINI, ADRIANA M.R.; IMAMURA, KELY B.; ALCANTARA, ADRIELI de O.; CAMPOS, FABIANI K. de; BISPO, SUZANA do R.; SÁ, ANA P.N. de . Kit de sopa de vegetais minimamente processados direcionados à classe infantil. In: SIMPÓSIO LATINO AMERICANO DE CIÊNCIA DE ALIMENTOS, 12th, November 4-7, 2017, Campinas, SP. Abstract... Campinas, SP: Galoá, 2017.

    Abstract: Desde a infância cada indivíduo já apresenta suas preferências alimentares, estas, nesta fase existe uma grande preferência por alimentos mais calóricos com quantidades elevadas de carboidratos, açúcar, gordura, sal, e baixo consumo de alimentos como vegetais e frutas. O objetivo do Kit de sopa de vegetais minimamente processados em formatos infantis teve como intuito despertar a curiosidade das crianças a consumi-los; bem como avaliar sua composição centesimal, segurança microbiológica e aceitabilidade infantil. Os vegetais escolhidos para montar o kit foram batata inglesa, cenoura e mandioquinha-salsa, os mesmos foram transportados para o Laboratório de Processamento da FATEC/Marília/SP, onde foi realizado o processamento mínimo. O kit foi acondicionado em sacos plásticos a vácuo e mantidos a 5°C por 8 dias. As análises microbiológicas foram efetuadas no primeiro dia do processamento mínimo, a composição centesimal foi avaliada no oitavo dia de armazenamento. Realizou-se a análise sensorial com 107 crianças entre 6 a 8 anos em uma Escola Municipal de Ensino Fundamental da cidade de Vera Cruz/SP. A partir dos resultados obtidos, verificou-se que o kit de vegetais minimamente processados apresentou qualidade nutricional, ausência de salmonella spp. e coliformes termotolerantes dentro dos limites permitidos pela legislação vigente. Foi constatado que a sopa elaborada com o Kit de vegetais em formatos lúdicos, obteve aceitação de 94,39% pelas crianças, demonstrando ser uma alternativa de alimentação saudável e ao mesmo tempo divertida. A vida útil do kit foi de 8 dias sob refrigeração à 5ºC.

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  • IPEN-DOC 26894

    NEGRAO, BIANCA ; VILLAVICENCIO, ANNA L.C.H. . Use of medium and high doses of ionizing radiation in cassava starch. In: SIMPÓSIO LATINO AMERICANO DE CIÊNCIA DE ALIMENTOS, 12th, November 4-7, 2017, Campinas, SP. Abstract... Campinas, SP: Galoá, 2017.

    Abstract: Cassava starch is susceptible to microbial changes, which can affect its shelf life. Ionizing radiation is used in doses sufficient to reduce microorganisms. However, when being exposed to starch granule it can cause changes in structure when compared to other methods. The aim of the work was to irradiate starches with medium and high doses in order to observe the effects on color of cassava starch and texture of tapioca. The starch samples were purchased in supermarkets in two types: starches with preservative (Fc – sodium metabisulphite) and starch without preservative (Fs). They were then irradiated at doses of 0, 5, 10 and 15 kGy in a 60Co Gamma cell 220 with dose rate of 0.764kGy/h-1. Subsequently, the samples were evaluated on 1st, 15th and 30th day after irradiation. The results show that in relation to the tonality (h°) there was a significant difference (P> 0.05) between the control and the irradiated samples on the 30th day. It's worth mentioning that, Fc and Fs had similar behavior at dose of 10 kGy, showing averages nearly h= 90º (Fs: 90.6±0,4; 90.0±0,3; 90.4±0,50 and Fc: 90.5±0,3; 89.9±1,6; 89,5±2,9 on the 1st, 15th and 30th day, respectively) indicating that the samples turned yellowed according to storage days. This tendency towards the yellow color can be attributed to the modification of reactions of the starch monosaccharide’s. The radiation can influence the rupture of surface the starch. For this reason, the tapioca showed increase in hardness (N) according to the increase of radiation dose as well as with storage days. However, on the 30th day, Fc showed no significant difference between doses of 5kGy (10.06); 10kGy (11.44) and 15kGy (11.67). The analysis of the results allows concluding that in this product it's possible use doses up to 10kGy because not change considerably the parameters studied.

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  • IPEN-DOC 26893

    SÁ, ANA P.N. de ; VILLAVICENCIO, ANNA L.C.H. . Características do efeito da radiação ionizante em farofas de carne seca e “bacon”. In: SIMPÓSIO LATINO AMERICANO DE CIÊNCIA DE ALIMENTOS, 12th, November 4-7, 2017, Campinas, SP. Abstract... Campinas, SP: Galoá, 2017.

    Abstract: A farofa está presente diariamente nas refeições dos brasileiros. A irradiação é utilizada pela indústria alimentícia. Avaliamos os efeitos da radiação ionizante em farofa de bacon (FB) e carne seca (FC) nas características de cor e atividade de água. As amostras obtidas no comercio de São Paulo foram irradiadas no acelerador de elétrons no Centro de Tecnologia das Radiações do IPEN/CNEN-SP com doses de 0; 1; 5 e 10 kGy. A cor foi realizada no colorímetro Minolta Chroma Meter modelo CR200b digital e a atividade de água (Aw) no aparelho digital Aqualab, modelo 4TE Duo (Decagon Devices Inc.). As análises foram processadas em temperatura de 25°C±1. Análise de variância (ANOVA) e teste de Tukey com 5% de significância foram aplicados. Observamos no dia 1 de armazenamento a coloração amarelada que se intensificou no decorrer do experimento em todas as doses aplicadas em FB e a FC apresentou diferença significativa na dose de 5kGy. No dia 15, para as duas farofas houve uma diminuição significativa do Croma (C*) para todas as doses e houve uma alteração significativa do tom avermelhado (a*) para as FC. No dia 30, para as duas farofas foi encontrada uma diferença significativa no parâmetro a* das doses de 1 e 5kGy em relação ao controle. Não houve diferença significativa entre 1 e 10kGy. Autores apresentam dados relacionados a farinhas e não a farofas. Os resultados relacionado a Aw de FB mostraram que não houve diferença significativa nas amostras de 1 e 15 dias, porém em 30 dias, as diferenças são significativas. Nas FC foram observadas diferenças significativas em todo o experimento., confirmando a hipótese que a Aw está relacionada com a maioria das reações de degradação de natureza química, enzimática e física. Concluímos que a radiação em doses altas promove alterações em relação ao tempo de armazenamento.

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  • IPEN-DOC 26892

    ALIBHAI, A.Y.; PRETTO, LUCAS R. de ; MOULT, ERIC M.; OR, CHRIS; ARYA, MALVIKA; MCGOWAN, MITCHELL; CARRASCO-ZEVALLOS, OSCAR; LEE, BYUNGKUN; CHEN, SIYU; BAUMAL, CAROLINE R.; WITKIN, ANDRE J.; REICHEL, ELIAS; FREITAS, ANDERSON Z. de ; DUKER, JAY S.; FUJIMOTO, JAMES G.; WAHEED, NADIA K.. Quantification of retinal capillary nonperfusion in diabetics using wide-field optical coherence tomography angiography. RETINA, The Journal of Retinal and Vitreous Diseases, v. 40, n. 3, p. 412-420, 2020. DOI: 10.1097/IAE.0000000000002403

    Abstract: Purpose: To combine advances in high-speed, wide-field optical coherence tomography angiography (OCTA) with image processing methods for semiautomatic quantitative analysis of capillary nonperfusion in patients with diabetic retinopathy (DR). Methods: Sixty-eight diabetic patients (73 eyes), either without retinopathy or with different degrees of retinopathy, were prospectively recruited for volumetric swept-source OCTA imaging using 12 mm · 12 mm fields centered at the fovea. A custom, semiautomatic software algorithm was used to quantify areas of capillary nonperfusion. Results: The mean percentage of nonperfused area was 0.1% (95% confidence interval: 0.0–0.4) in the eyes without DR; 2.1% (95% confidence interval: 1.2–3.7) in the nonproliferative DR eyes (mild, moderate, and severe), and 8.5% (95% confidence interval: 5.0–14.3) in the proliferative DR eyes. The percentage of nonperfused area increased in a statistically significant manner from eyes without DR, to eyes with nonproliferative DR, to eyes with proliferative DR. Conclusion: Capillary nonperfusion area in the posterior retina increases with increasing DR severity as measured by swept-source OCTA. Quantitative analysis of retinal nonperfusion on wide-field OCTA may be useful for early detection and monitoring of disease in patients with diabetes and DR.

    Palavras-Chave: tomography; coherent radiation; optical activity; optical properties; computerized tomography; ischemia; retina; diabetes mellitus; patients; perfused organs; capillaries; statistical data

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  • IPEN-DOC 26891

    YOSHIMURA, TANIA ; RIBEIRO, MARTHA S. . Photobiomodulation activates glucose uptake in brown adipose tissue of obese mice. Lasers in Medical Science, v. 35, n. 1, p. 280-280, 2020. DOI: 10.1007/s10103-019-02900-7

    Abstract: Mammal fat consists ofwhite and brown adipose tissues (WATand BAT). Although most fat is energy-storing WAT, brown adipocytes dissipate energy as heat. Obese subjects exhibit BAT hyporesponsiveness to classical stimuli as cold, hence increasing BAT thermogenic capacity could be an i n t er e s t i n g t a rget f o r t r eating obesity. Photobiomodulation (PBM) seems to be a feasible alternative to activate BAT, although it has not been applied for this purpose until now. In this study, adult C57Bl/6 mice were fed with a hyperlipidic diet (HF) during 15 weeks to induce obesity. Then, they were divided into two groups: HF and HF660. The interscapular BAT of HF660 mice was exposed to a single irradiation using a 662 ± 20 nm LED (5.7 Jcm-2 at 19 mWcm-2, delivered during 300 s). The HF group was sham-irradiated. Eutrophic animals were also used. Animals received 200 mCi of 18F-FDG and were exposed to cold for basal register of PET-CT images. After PBM or sh am treat ment, mice were once again exposed to cold before PET-CT image acquisition. Our results showed that PBM was able to activate BAT in obese mice through higher glucose uptake. In contrast, PBM and shamirradiated normal fed mice presented similar levels of glucose uptake. Taking together, our findings suggest that PBM applied to the BAT is able to promote glucose uptake by obese mice and could be an interesting approach to manage obesity and its correlated morbidities.

    Palavras-Chave: adipose tissue; glucose; metabolic diseases; mice; irradiation

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  • IPEN-DOC 26890

    NUNEZ, SILVIA C.; SILVA, IVES C. da; NASCIMENTO, JONATHAN S.; RIBEIRO, MARTHA S. . Methodological study of photobiomodulation anti-edematous effects on carrageenan-induced inflammation on zebrafish. Lasers in Medical Science, v. 35, n. 1, p. 288-289, 2020. DOI: 10.1007/s10103-019-02900-7

    Abstract: The anti-inflammatory action of Photobiomodulation (PBM) is one of its most reproducible effects in vivo. New models to study PBMeffects and to investigate light dosimetry may bring different perspectives on the field. Based on the importance of establishing new experimental models and the advantages of using zebrafish for screening new drugs with potential anti-inflammatory effects the present investigation evaluated the effect of PBM on carragenan-induced abdominal edema in zebrafish. Thirty Danio rerio (± 1 g) zebrafish were randomly divided into five aquariums with 0.25L of water to establish three treatments: T1 - Naive non-treated; T2 – Saline 0.9%-injected; T3 - carrageenan-injected (CG) 3.5% in the coelomic cavity. T4 –injected (CG) 3.5% and treated with a diode laser λ=808nm, 50mWand 0.5J T5 –same parameters with 1J and T6 -1.5J. Abdominal volumes were measured by a caliper and the area was calculated 4 hours post-indu ction. Four hours after edema induction the results revealed an increase in the abdominal area of fish injected with CG 3.5% compared to negative control. The animals injected with CG and treated with PBM exhibited a reduction in abdominal edema in a dose-dependent manner. The 0.5J energy did not present a significant reduction compare do control (p=0.18), the 1J and 1.5J groups presented a significant difference (p=0.027 and p=0.005 respectively). The 1.5J group was not different from negative control (T2) p=0.37. The present study identified that zebrafish may represent a good model to investigate PBM effects and the response was dose dependent.

    Palavras-Chave: inflammation; fishes; antipyretics; dosimetry; biological effects

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  • IPEN-DOC 26889

    SILVA, C.R. ; RIBEIRO, M.S. . Effects of photobiomodulation on breast tumor- bearing mice before radiotherapy. Lasers in Medical Science, v. 35, n. 1, p. 269-269, 2020. DOI: 10.1007/s10103-019-02900-7

    Abstract: Photobiomodulation (PBM) has been studied to modify the cellular response to ionizing radiation. However, its combination with radiotherapy (RT) has not been reported in cancer treatment. The aim of this study was to evaluate the effects of PBM applied before RT on breast tumor-bearing mice. Female BALB/c mice were inoculated with breast 4T1 cells into mammary fat pad and divided into 4 groups (n =5 per group): control (with no treatment), only RT, and PBM combined to RT in two different protocols. RT was locally applied using a 60Co source with dose of 60 Gy in fractions of 15 Gy. For PBM, a red laser (660 nm, 500 mW/cm2) was used in two regimes: single exposure 24 h before RT (fluence of 150 J/cm2) and immediately before each RT session (fluence of 37.5 J/cm2 per session). After treatment, tumor volume, platelets, white and red blood cell levels were evaluated during 14 days. Our results showed no statistically significant differen ces in t umor volume, platelet and red blood cell levels comparing control, RT and PBM+RT groups. However, PBM was able to sustain normal white blood cell levels compared to RT and control groups. In addition, mice that received PBM concomitant with RT presented a longer survival. In fact, for this group only 12.5 % of the animals died during experimental period. These findings indicate that PBM could be combined to RT to provide therapeutic anti-cancer benefits.

    Palavras-Chave: ionizing radiations; therapy; neoplasms; tumor cells; mice; mammary glands; radiotherapy

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  • IPEN-DOC 26888

    CONTATORI, C.G. de S. ; SILVA, C.R. ; YOSHIMURA, T.M. ; RIBEIRO, M.S. . Effects of low-level laser irradiation on VEGF expression of melanoma cell lines. Lasers in Medical Science, v. 35, n. 1, p. 269-269, 2020. DOI: 10.1007/s10103-019-02900-7

    Abstract: Impact of low-level laser irradiation on tumor cell lines remains controversial. Vascular endothelial growth factor (VEGF) is a key molecule to form new blood vessels, which contribute for cancer development and growth. The aim of this study was to evaluate the effects of different light fluences on human melanoma SKMEL 37 cells and murine melanoma B16F10 cells using a near infrared laser (λ= 780 nm) with output power of 40 mW delivering energies of 1.2, 3.6 and 6 J (fluences of 30, 90 and 150 J/cm2, respectively). The cell lines were irradiated 24 h after they were seeded in a 96-well plate at a density of 5x103 cells per well, in triplicate at three different days. Following irradiation, both cell line supernatants were stored in Eppendorf tubes at - 20°C until VEGF-A expression measurement. Specific ELISA kits were used according to cell line (murine or human). Samples and standard solutions were added in a 96-well plate antibody-coated and incuba ted over night at 4°C. Reagent dilution and set time followed fabricant instructions. The stop solution was added and the absorbance was read in a microplate reader at 450 nm. Results showed a non-statistically significant difference among treated and control groups for both cell lines. These findings indicate that irradiation with near infrared laser does not influence VEGF expression on melanoma cell lines regardless the fluence used and should be tested to prevent cancer growth in preclinical assays.

    Palavras-Chave: laser radiation; low dose irradiation; doses; irradiation; tumor cells; melanomas; enzyme immunoassay

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  • IPEN-DOC 26684

    PEREIRA, S.T. ; SILVA, C.R. ; RIBEIRO, M.S. . A single application of low-level light therapy in breast cancer-bearing mice: impact on blood cell count. Lasers in Medical Science, v. 35, n. 1, p. 274-274, 2020. DOI: 10.1007/s10103-019-02900-7

    Abstract: Low-level light therapy (LLLT) has been used in healthcare as a therapeutic strategy for diseases of various aetiologies. However, its effects on cancer is controversial. The aim of this work was to evaluate the effects of different light doses on blood cell count of breast cancer-bearing mice after a single application of LLLT. Tumour was induced by inoculation of 4T1 cells into the mammary fat pad of female BALB/c mice. Tumour volume was monitored with a digital calliper and when it reached 100 mm3, animals were irradiated by a red LED irradiator (660 ± 20 nm) at irradiance of 24.3 mW/cm2. The animals were randomly divided into groups (n= 5/group) that received energy densities of 1.8, 5.6 and 9.4 J/cm2. Control group was equally manipulated but did not receive irradiation. After treatment, data as tumour volume, platelets, white and red cell levels were registered weekly during 21 days. Our results showed that irradiated groups presented a longer survival compared to the control group, although no significant differences were observed among groups regarding tumour volume. Platelet levels of the irradiated groups remained closer to the reference values of healthy animals. Regarding the total number of white and red cells, no significant differences were observed between control and treated groups. These findings indicate that LLLT in a single application did not arrest tumour growth but may maintain platelet levels to increase survival of mice regardless the energy density protocol used.

    Palavras-Chave: blood cells; light emitting diodes; neoplasms; dose rates; blood platelets

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  • IPEN-DOC 26673

    MANTECON, JAVIER G.; MATTAR NETO, MIGUEL . Numerical investigation on the effects of geometric deviations and materials properties on flow-induced deflections of fuel plates. Annals of Nuclear Energy, v. 140, p. 1-10, 2020. DOI: 10.1016/j.anucene.2019.107118

    Abstract: This work describes multiphysics analyses conducted to investigate the effect of geometric deviations and materials properties on flow-induced deflections of fuel plates. The analyzed configuration consists of two fuel plates and each one of them is bounded by two fluid channels. The fluid-dynamic forces acting on the plates are calculated using a Computational Fluid Dynamics model and the structural response is determined by means of a Finite Element Analysis model. Both models are coupled using the two-way fluid-structure interaction approach. The results show that manufacturing deviations from the nominal conditions and the increment of the system temperature lead to reduce the critical fluid velocity of the assembly.

    Palavras-Chave: fuel plates; geometry; mathematical models; fuel elements; research reactors; numerical analysis; physical properties

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  • IPEN-DOC 26882

    TEIXEIRA, LUIZ F.S. ; PERON, JEAN P.S.; BELLINI, MARIA H. . Silencing of nuclear factor kappa b 1 gene expression inhibits colony formation, cell migration and invasion via the downregulation of interleukin 1 beta and matrix metallopeptidase 9 in renal cell carcinoma. Molecular Biology Reports, v. 47, n. 2, p. 1143-1151, 2020. DOI: 10.1007/s11033-019-05212-9

    Abstract: Renal cell carcinoma (RCC) is a highly deadly urological tumor due to its high metastatic incidence and its notorious chemoresistance. The nuclear transcription factor kappa B (NF-κB) family has been associated with apoptosis resistance and cellular invasion in RCC. The purpose of this study was to evaluate the impact of NF-κB1 gene silencing on the colony formation, cell migration and invasion abilities of the RCC cell line. Renca–mock and Renca-shRNA-NF-κB1 cells were used in this work. NF-κB1 downregulation was assessed by western blotting. The mRNA expression levels of interleukin-1 beta (IL-1β) and MMP-9 were assessed by real-time quantitative polymerase chain reaction (RT-qPCR). The IL-1β levels in the culture media were determined by a commercial ELISA kit. The MMP-9 protein expression and gelatinolytic activity were evaluated by western blotting and zymography, respectively, and the migration and invasion abilities were analysed. The expression levels of p105 and p50 in Renca-shRNA-NF-κBmoc1 cells were significantly reduced compared with those in the Renca–mock cells. The colony numbers of shRNA-NF-кB1 cells were lower than the colony numbers of the Renca– mock cells. NF-κB1 knockdown inhibited the cell migration and invasion of Renca-shRNA-NF-κB1 cells. These cells also exhibited reduced levels of IL-1β. The MMP-9 expression and activity levels were significantly reduced in Renca-shRNANF- κB1 cells. Taken together, these results indicate that the downregulation of NF-κB1 suppresses the tumourigenicity of RCC by reducing MMP-9 expression and activity; thus, NF-κB1 could be a molecular target for RCC treatment.

    Palavras-Chave: kidneys; carcinomas; transcription factors; colony formation; migration; carcinogenesis; transcription; transcription factors; antigens; proteins

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  • IPEN-DOC 26876

    CORAZZA, FULVIO G.; ERNESTO, JULIA V.; NAMBU, FELIPE A.N.; CARVALHO, LUMA R. de ; LEITE-SILVA, VANIA R.; VARCA, GUSTAVO H.C. ; CALIXTO, LEANDRO A.; VIEIRA, DANIEL P. ; ANDREO-FILHO, NEWTON; LOPES, PATRICIA S.. Papain-cyclodextrin complexes as an intestinal permeation enhancer: permeability and in vitro safety evaluation. Journal of Drug Delivery Science and Technology, v. 55, p. 1-11, 2020. DOI: 10.1016/j.jddst.2019.101413

    Abstract: Oral drug delivery is the main route for drugs administration. However, some drugs have poor permeability across the intestinal barrier. Papain has been widely used in pharmaceutical applications due to its debridement properties and the ability to promote skin permeation of drugs. It is known that papain complexation with cyclodextrins improves its biological stability. In this paper, the ability of the native papain-cyclodextrin complexes is shown be an oral permeation enhancer to furosemide, using a Caco-2 monolayer system to evaluate drug permeability and apparent permeability coefficient. Analysis of the in vitro cytotoxicity over CHO–K1, Hep G2 and Caco-2 cell lines and genotoxicity over CHO–K1 and Hep G2 cell lines were also performed. Papaincyclodextrins complexes did not show any cytotoxicity above 31 μg/mL. No significant genotoxic damage was observed. Papain and cyclodextrin complexes induced almost 2.5-fold increase in furosemide permeation compared to controls, and maintenance of the paracellular integrity of the Caco-2 cells monolayer was confirmed. The papain complexes may be safely applied in pharmaceutical formulations, not only as a therapeutic agent but also as a strategic pharmaceutical adjuvant, promoting permeation of low oral permeability drugs.

    Palavras-Chave: papain; chelating agents; oligosaccharides; drugs; antimitotic drugs; enzymes; enzyme activity; membrane transport

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  • IPEN-DOC 26666

    VEGA, L.E.R.; LEIVA, D.R.; LEAL NETO, R.M. ; SILVA, W.B.; SILVA, R.A.; ISHIKAWA, T.T.; KIMINAMI, C.S.; BOTTA, W.J.. Improved ball milling method for the synthesis of nanocrystalline TiFe compound ready to absorb hydrogen. International Journal of Hydrogen Energy, v. 45, n. 3, p. 2084-2093, 2020. DOI: 10.1016/j.ijhydene.2019.11.035

    Abstract: In this study, we propose a method to produce nanocrystalline TiFe powder by high-energy ball milling, in order to avoid the common sticking problem of the material to the milling tools, assuring a material prompt to absorb hydrogen as well. The method consists of making a preliminary milling operation with the elemental powders (50:50 stoichiometric ratio) to form a strong adhered layer of the milled material on the surfaces of the vial and balls. The main milling operation is then performed with a new powder charge (same composition as before), but now adding a process control agent (stearic acid). Various processing times - 2, 6, 10 and 20 h - were used in the milling experiments. Nanocrystalline TiFe was synthesized in this way with low oxygen contamination, full yields for milling times of 6 h or over, requiring no heat treatments for the first hydrogen absorption. Hydrogen storage capacity of 1.0 wt% at room temperature under 20 bar was attained by the sample milled for 6 h. Kinetic data from samples milled for 2 h and 6 h agreed with Jander model for the rate limiting step of the hydriding reaction, which is based on diffusion with constant interface area.

    Palavras-Chave: intermetallic compounds; alloys; mechanical properties; nanocrystals; milling; hydrogen storage; hydrides; activation analysis

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  • IPEN-DOC 26665

    SUZUKI, MIRIAM F. ; OLIVEIRA, JOAO E. ; DAMIANI, RENATA; LIMA, ELIANA R. ; AMARAL, KLEICY C. ; SANTOS, ANDERSON M. de S.; MAGALHÃES, GERALDO S.; FAVERANI, LEONARDO P.; PEREIRA, LUIS A.V.D.; SILVA, FABIANA M.; BARTOLINI, PAOLO . Human bone morphogenetic protein‑2 (hBMP‑2) characterization by physical–chemical, immunological and biological assays. AMB Express, v. 10, n. 1, p. 1-10, 2020. DOI: 10.1186/s13568-020-0964-5

    Abstract: Commercially available preparations of methionyl-human BMP-2 and CHO-derived hBMP-2, which belongs to the transforming growth factor β (TGF-β) superfamily, were used for a complete characterization. This protein is an extremely efficient osteoinductor that plays an important role during bone regeneration and embryonic development. Characterization was carried out via SDS-PAGE and Western blotting, followed by reversed-phase HPLC, sizeexclusion HPLC and MALDI-TOF-MS. The classical in vitro bioassay, based on the induction of alkaline phosphatase activity in C2C12 cells, confirmed that hBMP-2 biological activity is mostly related to the dimeric form, being ~ 4-fold higher for the CHO-derived glycosylated form when compared with the E. coli counterpart. The E. coli-derived methBMP- 2 has shown, by MALDI-TOF-MS, a large presence of the bioactive dimer. A more complex molecular mass (MM) distribution was found for the CHO-derived product, whose exact MM has never been reported because of its variable glycosylation. A method based on RP-HPLC was set up, allowing a quantitative and qualitative hBMP-2 determination even directly on ongoing culture media. Considering that hBMP-2 is highly unstable, presenting moreover an extremely high aggregate value, we believe that these data pave the way to a necessary characterization of this important factor when synthesized by DNA recombinant techniques in different types of hosts.

    Palavras-Chave: proteins; skeleton; human populations; bone cells; cho cells; bioassay; escherichia coli; connective tissue cells

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  • IPEN-DOC 26664

    CAMPOS, ALEX C.; PAES, SUANE C.; CORREA, BRUNO S.; CABRERA-PASCA, GABRIEL A.; COSTA, MESSIAS S.; COSTA, CLEIDILANE S.; OTUBO, LARISSA ; CARBONARI, A.W. . Growth of long ZnO nanowires with high density on the ZnO surface for gas sensors. ACS Applied Nano Materials, v. 3, n. 1, p. 175-185, 2020. DOI: 10.1021/acsanm.9b01888

    Abstract: Among the various approaches to grow semiconducting oxide nanowires, the thermal oxidation procedure is considered a simple, efficient, and fast method that allows the synthesis of micro and nanostructured arrangements with controlled size and morphology. In the work reported in this paper, long ZnO nanowires were synthesized on the surface of oxidized high-purity Zn foils by heating in air at different rates and temperatures. The size and morphology investigated by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) for a sample heated at 620 °C with heating rate of 20 °C/min reveal the growth of long ZnO nanowires with length of ∼50 μm and average diameter of 74 nm grown along the ⟨112̅0⟩ direction with high population density. Results with different heating rates indicates that this parameter is determinant in tuning the size, morphology, and population density of nanowires. X-ray diffraction (XRD) shows patterns for both ZnO and metallic Zn with preferential orientation, whereas perturbed angular correlation (PAC) measurements using 111In(111Cd) probe nuclei indicate that probe nuclei occupy only Zn sites in the preferential oriented metallic zinc. However, for samples submitted to high-temperature heating (820 and 1000 °C), XRD yields only the ZnO pattern and, amazingly, PAC continues showing probe nuclei only at metallic Zn sites indicating the presence of thin regions of highly oriented Zn trapped between grains of ZnO. Moreover, this strong preference of indium atoms (of parent radioactive 111In) here revealed helps to understand the oxidation mechanism and the growth of the nanowires.

    Palavras-Chave: zinc oxides; nanowires; electric fields; oxidation; temperature gradients; x-ray diffraction; thermal analysis; transmission electron microscopy

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  • IPEN-DOC 26441

    CARDOSO JUNIOR, MARCIO; CHEMALE JUNIOR, FARID; OLIVEIRA, CHRISTIE H.E. de; CRUZ, CARLOS E. de S.; ABREU, CARLOS J. de; GENEZINI, FREDERICO A. . Thermal history of potential gas reservoir rocks in the eastern Parnaíba Basin, Brazil. AAPG Bulletin, v. 104, n. 2, p. 305-328, 2020. DOI: 10.1306/05021918117

    Abstract: The Parnaíba Basin is a major intracratonic sedimentary basin in Brazil with unconventional petroleum systems as a potential natural resource formed by the influence of igneous intrusions. To constrain the thermal history of unexplored potential reservoir rocks in the eastern part of the Parnaíba Basin, sedimentary rocks near intrusions were analyzed by petrography and thermochronology (apatite fission-track [AFT] and zircon fission-track [ZFT] dating). Petrography shows grain dissolution and carbonate pore filling generated by thermal destabilization of feldspars. The AFT results indicate partial annealing by the last magmatic event in the basin, and ZFT results show ages of maximum paleotemperature compatible with the Sardinha magmatic event (120–130 Ma). In thermal history models, rocks close to intrusions experienced maximum paleotemperatures above 300°C, which is higher than what is considered favorable for reservoir rocks. Hydrothermal fluids modified the diagenetic evolution of the succession by dissolving and precipitating carbonate cement in pore spaces. In the studied area, at distances greater than 50m(>164 ft) from the intrusion, the rocks were not substantially altered, and in terms of paleotemperature, they can be considered potentially viable reservoirs. The thermal history analysis of potential tight gas sandstone reservoirs affected by intrusive bodies is valuable for characterizing the thermal enhancement or destruction of the reservoir’s qualities.

    Palavras-Chave: sedimentary basins; natural gas; reservoir rock; geologic deposits; petrography; sandstones; brazil; sedimentary rocks; petroleum geology

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  • IPEN-DOC 25852

    MESQUITA, C.H. ; VELO, A.F. ; CALVO, W.P. ; CARVALHO, D.V. ; HAMADA, M.M. . Emission and transmission tomography system applied to analyze industrial process inside chemical reactors. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, v. 954, p. 1-3, 2020. DOI: 10.1016/j.nima.2019.01.073

    Abstract: The tomography techniques are widely used in many industries, such as: chemical, food, pharmaceutical and oil sectors. In the industries the tomography is used to diagnose the state of the machines of production and also in the control of quality of the produced objects. A portable tomography system known as instant-non-scanning type, a similar version of the fourth generation CT, was developed in this work. It is capable to obtain measurements in real time conditions without interrupting the operation of the industrial production and it is useful in the quality control of the means of production and the objects produced. This paper describes an innovative hybrid industrial tomographic system, i.e., simultaneous data from the emission of an internal radioactive source introduced inside to the object (67Ga citrate) and tomographic transmission using five sources of 137Cs positioned externally to the object which are distributed at the vertices of a pentagon. The tomographic system described here is useful for studying dynamic chemical phenomena, associated or not with multiphase systems commonly found in chemical reactors and distillation columns.

    Palavras-Chave: cesium 137; diagnostic techniques; tomography; computerized tomography; image processing; nai detectors; citrates; gallium 67; external irradiation; trace amounts

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  • IPEN-DOC 25785

    MARIANO, KELLI C.F.; NASCIMENTO, MONICA H.M. do; QUEROBINO, SAMYR M.; CAMPOS, ESTEFANIA V.R.; OLIVEIRA, JHONES L. de; YOKAICHIYA, FABIANO; FRANCO, MARGARETH K.K.D. ; ALBERTO-SILVA, CARLOS; PAULA, ENEIDA de; LOMBELLO, CHRISTIANE B.; LIMA, RENATA de; FRACETO, LEONARDO F.; ARAUJO, DANIELE R. de. Influence of chitosan-tripolyphosphate nanoparticles on thermosensitive polymeric hydrogels: structural organization, drug release mechanisms and cytotoxicity. International Journal of Polymeric Materials and Polymeric Biomaterials, v. 69, n. 9, p. 592-603, 2020. DOI: 10.1080/00914037.2019.1596909

    Abstract: Chitosan-tripolyphosphate (CS-TPP) nanoparticles containing naproxen (NPX) were dispersed in poloxamer (PL) as unique (PL407) or binary (PL407-PL403) systems. Nanoparticles presented diameter of 250nm and zeta potential of 35mV with drug loading and encapsulation efficiency of 98.4 ± 0.3% and 36.9 ± 0.12%, respectively. NPX-CS-TPP shifted the sol-gel transition and micellization temperatures. PL407-PL403 systems presented G0 >G00 compared to PL407. SAXS patterns revealed transitions from lamellar to hexagonal phase organizations with low drug release rates, in the presence of CS-TPP nanoparticles. NPX-CS-TPP-PL407 induced lower cytotoxicity compared to PL407-PL403 in fibroblasts and osteoblasts, making them promising systems for intra-articular delivery.

    Palavras-Chave: polysaccharides; chitin; nanoparticles; antipyretics; drugs; viability; animal cells; sensitivity; temperature dependence; hydrogels

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  • IPEN-DOC 26887

    PRADO, E.S.P. ; MIRANDA, F.S.; PETRACONI, G.; POTIENS JUNIOR, A.J. . Use of plasma reactor to viabilise the volumetric reduction of radioactive wastes. Radiation Physics and Chemistry, v. 168, p. 1-4, 2020. DOI: 10.1016/j.radphyschem.2019.108625

    Abstract: Nuclear reactors, hospitals, industries and research institutes generate considerable amounts of radioactive waste every day. To dispose this waste in a safe and costeffective manner, it must be treated by immobilising the radionuclides and, for better stocking capacity, it must be volumetrically reduced as much as possible. To this end, plasma technology, among other promising technologies for radioactive waste treatment, exposes radioactive waste to temperatures above 1400 °C, thereby substantially reducing its volume. In the planning and managing 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 centres, thereby improving radioactive waste management. In this study, a thermal plasma treatment process was established, and a plasma reactor was used for compactable waste processing. After 30 min of thermal plasma treatment, the volume reduction factor reached 1:99. The results demonstrate the viability of using a thermal plasma process for the volumetric reduction of radioactive waste in a safe and cost-effective manner.

    Palavras-Chave: radioactive materials; radioactive wastes; radioactive waste management; plasma; reactors; radioactive waste storage; reduction; slags; volume; brazilian cnen; plasma technology

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  • IPEN-DOC 26886

    GARCIA, VANESSA S.G. ; ROSA, JORGE M.; BORRELY, SUELI I. . Toxicity and color reduction of a textile effluent containing reactive red 239 dye by electron beam irradiation. Radiation Physics and Chemistry, v. 172, p. 1-5, 2020. DOI: 10.1016/j.radphyschem.2020.108765

    Abstract: Textile effluents are a mixture of dyestuff, surfactants, dispersants, acids, alkalis and bleaching agents, among other compounds, and some of these are highly soluble and relatively recalcitrant. Suitable improvement of textile effluents may require combined treatment processes, such as Conventional Treatments and Advanced Oxidative Process (AOPs). Electron beam irradiation (EBI) has been proposed as a possible technology for the treatment of textile effluents. In this context, the aim of the present study was to evaluate the efficiency of an Electron Beam treatment applied to toxicity and color reduction of a textile effluent containing reactive Red 239 dye. Effluent COD and TOC were also evaluated. The assessed effluents were submitted to EBI treatment at doses ranging from 0.5 to 15 kGy. Vibrio fischeri bacteria and Daphnia similis crustaceans were exposed to both irradiated and non-irradiated effluents, the toxicity was evaluated through EC50 (median effective concentration) calculations. EB irradiation successfully reduced effluent toxicity and color. The EC50 for D. similis(48h) were of 6.31% ± 3.19 (non-irradiated) and 27.56% ± 9.31 (10 kGy), and for V. fischeri(15min), of 7.41% ± 1.52 (nonirradiated) and 31.89% ± 10.99 (10 kGy), respectively. Approximately 70% toxicity reduction was obtained for both organisms, while 95% color reduction was obtained by applying 5 kGy.

    Palavras-Chave: toxicity; textiles; effluents; dyes; color; electron beams; textile industry; bacteria; crustaceans; experimental data; environmental impacts; toxic materials; decomposition

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  • IPEN-DOC 26885

    KLUMPP, RAFAEL E. ; DONATUS, UYIME ; ARAUJO, JOAO V.S. ; REDÍGOLO, MARCELO M. ; MACHADO, CARULINE de S.C. ; COSTA, ISOLDA . The effect of acid pickling on the corrosion behavior of a cerium conversion-coated AA2198-T851 Al-Cu-Li alloy. Journal of Materials Engineering and Performance, v. 29, n. 1, p. 167-174, 2020. DOI: 10.1007/s11665-019-04551-9

    Abstract: The effect of acid pickling pretreatments prior to cerium conversion coating process on the corrosion behavior of AA2198-T851 alloy substrates was investigated. Three acid pretreatments were employed: nitric acid (HNO3), phosphoric acid (H3PO4) and sulfuric acid (H2SO4). The cerium conversion coating process was performed using a batch solution composed of cerium nitrate and hydrogen peroxide. Microscopic techniques, electrochemical impedance spectroscopy, polarization resistance and open-circuit potential measurements were employed to investigate the effect of each acid pretreatment. The untreated and nitric acid pretreated substrates presented more defective cerium conversion layers than the substrates treated with phosphoric and sulfuric acids. Accordingly, the corrosion resistance of the untreated and nitric acid-treated substrates was very low, while that of the substrates treated with phosphoric acid and sulfuric acids were greatly improved. The sulfuric acid pickling treatment was the best pretreatment before cerium conversion coating among the investigated pretreatments on the AA2198-T851 Al-Cu-Li alloy.

    Palavras-Chave: inorganic acids; pickling; corrosion pickling; cerium; nitric acid; phosphoric acid; sulfuric acid; coatings; conversion; aluminium alloys; lithium alloys; copper alloys; electrochemistry; corrosion resistance

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  • IPEN-DOC 26884

    BENTO, RODRIGO T. ; FERRUS FILHO, ANDRE; FUMAGALLI, MARCO A.. Structural design and stress analysis of a high-speed turbogenerator assembly supported by hydrodynamic bearings. International Journal of Manufacturing, Materials, and Mechanical Engineering, v. 10, n. 1, p. 54-67, 2020. DOI: 10.4018/IJMMME.2020010104

    Abstract: Turbine and bushing bearing are the most critical components of high-speed machines. This article describes the design of a high-speed turbine supported by hydrodynamic bearings. The mathematical dimensioning and the FEM analysis are presented to validate the mechanical strength of the turbine and the bushing bearing models. Fatigue life and factor of safety were also determined. The simulations showed that the maximum Von Mises stress values obtained are associated to the centrifugal force generated by the system rotational movement. The results variation was mainly due to the properties of the materials proposed. For the turbine, 7075-T6 aluminum alloy and SAE 4340 steel obtained satisfactory behavior under a constant operating speed of 30,000 RPM. For the hydrodynamic bearing, the TM23 bronze alloy exhibited excellent results, without fracture, and low mechanical deformation. The models exhibited a great potential employment in several applications, such as biogas systems to generate electrical energy, and educational test bench for thermodynamic and tribological simulations.

    Palavras-Chave: steam turbines; velocity; hydrodynamics; bearings; finite element method; design; stress analysis; wind turbines; turbogenerators

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  • IPEN-DOC 26883

    FAZOLIN, GABRIELA N. ; VARCA, GUSTAVO H.C. ; FREITAS, LUCAS F. de ; ROKITA, BOZENA; KADLUBOWSKI, SLAWOMIR; LUGAO, ADEMAR B. . Simultaneous intramolecular crosslinking and sterilization of papain nanoparticles by gamma radiation. Radiation Physics and Chemistry, v. 171, p. 1-7, 2020. DOI: 10.1016/j.radphyschem.2020.108697

    Abstract: Papain-based nanoparticles were recently developed using radiation technologies and proven effective to generate nanosized crosslinked papain particles with preserved enzymatic activity. The applications of such nanostructured systems are expected to be similar to native papain with considerable biopharmaceutical advantages and concern drug loading among other biotechnological applications. The nature of such crosslinks and the possibility to provide simultaneous sterilization have been hypothesized but remain not totally clarified. This manuscript advances the discussion on the radiation-induced synthesis of protein nanoparticles by approaching the nature of the crosslinking and the possible contribution of bityrosine linkages and disulfide bridges to the overall nanoparticle assembly as well as the feasibility of the simultaneous sterilization process under the preestablished conditions of processing. Papain nanoparticles were synthesized and characterized according to size, proteolytic activity, bityrosine, cysteine content and molecular weight by SDS-PAGE upon sonication at 40 kHz. Bacterial identification and the sterility tests were performed in accordance with ISO 11737 prior to and after inoculating 106 CFU of Corynebacterium xerosis. Our experiments evidenced the crosslinking of rather intra- than intermolecular nature and a contribution of cysteine bridges and bityrosine linkages to the stabilization and formation of the papain nanoparticle assembly. The technique was effective to promote simultaneous crosslinking and sterilization at the established conditions of processing and may be validated in accordance with the ISO 11137.

    Palavras-Chave: papain; sh-proteinases; nanoparticles; gamma radiation; proteins; cross-linking; sterilization; bacteria; disulfides

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  • IPEN-DOC 26881

    VIANA, ITALLO E.L.; LOPES, RAQUEL M.; SILVA, FLAVIA R.O. ; LIMA, NELSON B. ; ARANHA, ANA C.C.; FEITOSA, SABRINA; SCARAMUCCI, TAIS. Novel fluoride and stannous -functionalized β-tricalcium phosphate nanoparticles for the management of dental erosion. Journal of Dentistry, v. 92, p. 1-6, 2020. DOI: 10.1016/j.jdent.2019.103263

    Abstract: Objective: To evaluate the anti-erosive effect of solutions containing β-tricalcium phosphate (β-TCP) nanoparticles functionalized with fluoride or with fluoride plus stannous on enamel and dentin. Methods: β-TCP nanoparticles were synthesized and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Sixty enamel and dentin specimens were randomly allocated into the groups (n=10): Control (water); F (NaF, 225 ppm F−); F+Sn (NaF+SnCl2, 800 ppm Sn2+); F+β-TCP (F+40 ppm β- TCP); F+Sn+β-TCP (F+Sn+40 ppm β-TCP); F+Sn+100β-TCP (F+Sn+100 ppm β-TCP). Specimens underwent erosion-remineralization cycling (5 min immersion into 1 % citric acid solution and 60 min exposure to artificial saliva, 4×/day, 5 days). Immersion in the test solutions was performed for 2 min, 2×/day. Surface loss (SL, in μm) was determined by optical profilometry at the end of cycling. Data were analyzed using one way- ANOVA and Tukey’s tests (α=0.05). Results: XRD confirmed the β-TCP phase. TEM micrographs showed differences between the bare nanoparticle and the β-TCP functionalized with F and Sn. All enamel groups presented lower SL than the control, with F+Sn, F+Sn+β-TCP, and F+Sn+100β-TCP showing the lowest values. For dentin, all the groups had lower SL than the control. F+β-TCP presented the lowest SL, significantly differing from all the other groups. Conclusion: β-TCP nanoparticles functionalized with fluoride showed improved anti-erosive effect compared to the fluoride solution on dentin. There was no significant effect of the β-TCP nanoparticles functionalized with fluoride plus stannous in both substrates. Clinical Relevance: β-TCP nanoparticles are a promising agent to be added to oral health products to improve the protective effect of fluoride against dentin erosion.

    Palavras-Chave: dentistry; caries; pathological changes; fluorides; enamels; tin fluorides; nanoparticles; tcp; erosion control; mineralization

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  • IPEN-DOC 26880

    PALACIOS, RAFAEL da S.; ROMERA, KELLY S.; CURADO, LEONE F.A.; BANGA, NELSON M.; ROTHMUND, LUCAS D.; SALLO, FERNANDO da S.; MORAIS, DENES; SANTOS, ANNA C.A.; MORAES, TONNY J.; MORAIS, FERNANDO G. ; LANDULFO, EDUARDO ; FRANCO, MARCO A. de M.; KUHNEN, IGOR A.; MARQUES, JOÃO B.; NOGUEIRA, JOSE de S.; VALLE JUNIOR, LUIZ C.G. do; RODRIGUES, THIAGO R.. Long term analysis of optical and radiative properties of aerosols in the Amazon Basin. Aerosol and Air Quality Research, v. 20, n. 1, p. 139-154, 2020. DOI: 10.4209/aaqr.2019.04.0189

    Abstract: The Amazon region is an excellent laboratory for analysis of natural aerosols in the wet season; however, in the dry season the biomass burning emissions highly influence it, which considerably alters the physical and chemical properties of the atmosphere. We analyzed long-term time series (2000–2017) of optical and radiative properties of aerosols during dry and rain seasons from nine AERONET stations located in the Amazon Basin (Western Brazil). Aerosols have been classified into two groups: organic carbon (OC) and elemental carbon (EC), which allowed quantification of their effects on the radiative forcing for these sites. It was possible to conclude that the optical depth values of aerosols (AOD 500 nm), which remained in a downward inclination beginning in 2010 to 2012, returned to rise since 2013. The analysis showed that the fraction of biogenic particles varied from approximately 38% to 67% at the site of Manaus EMBRAPA. However, for ATTO this fraction remained practically constant throughout the year, around 68% as the fraction of OC-EC went from approximately 16 to 27%. In that way, the study found that in the central Amazon region, in the dry season, the OC fraction generates instantaneous effects of up to –100 W m–2 in the radiative surface forcing (FR-Surface), while in the Cerrado region (Cuiabá) the instantaneous values reached up to –350 W m–2. The impact of the primary biogenic particles on the radiative flux resulted in a mean, approximately –20 W m–2 FR-Surface, representing 45% of the total effect caused by aerosols in the Amazon.

    Palavras-Chave: aerosols; optical depth curve; albedo; backscattering; scattering; aerosol monitoring; air quality; optical properties

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  • IPEN-DOC 26879

    SANTOS, NATHALIA V. dos; VIEIRA, CAROLINA L.Z.; SALDIVA, PAULO H.N.; MAZZILLI, BARBARA P. ; SAIKI, MITIKO ; SAUEIA, CATIA H. ; DE ANDRE, CARMEN D.S.; JUSTO, LISIE T.; NISTI, MARCELO B. ; KOUTRAKIS, PETROS. Levels of Polonium-210 in brain and pulmonary tissues: preliminary study in autopsies conducted in the city of São Paulo, Brazil. Scientific Reports, v. 10, n. 1, p. 1-7, 2020. DOI: 10.1038/s41598-019-56973-z

    Abstract: The accumulation of detectable amounts of radon progeny in human tissues may be a risk factor for development and progression of chronic diseases. In this preliminary study, we analyzed the levels of alpha-emitting radon progeny Polonium-210 (210Po) in the olfactory epithelium, olfactory bulb, frontal lobe, and lung tissues in cadavers from the city of Sao Paulo, SP, Brazil. We also assessed the association between 210Po levels and exposure parameters for urban air pollution using linear regression models adjusted for age, sex, smoke, time living in Sao Paulo, daily commuting, socioeconomic index, and anthracosis (traffic-related black carbon accumulation in the pleural region and in lymph). Our findings show that the concentration of 210Po was associated with anthracosis in lungs of nonsmokers (coefficient = 6.0; standard error = 2.9; p = 0.04). Individuals with lower socioeconomic status also had significantly higher 210Po levels in lungs (coefficient = −1.19; standard error = 0.58; p = 0.042). The olfactory bulb had higher 210Po levels than either olfactory epithelium (p = 0.071), frontal lobe (p < 0.001), or lungs (p = 0.037). Our findings of the deposition of 210Po in autopsy tissues suggest that airborne radionuclides may contribute to the development of chronic diseases, including neurodegenerative diseases.

    Palavras-Chave: body composition; autopsy; polonium 210; progeny; radon; animal tissues; lungs; brain; epithelium; tobacco smokes; air pollution; human populations; urban populations; brazil

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  • IPEN-DOC 26878

    TESSARO, ANA P.G. ; ARAUJO, LEANDRO G. de ; VICENTE, ROBERTO . Inventorying the radionuclides in spent cartridge filters from the primary circuit of a nuclear research reactor by the dose-to-activity method. Radiation Physics and Chemistry, v. 171, p. 1-6, 2020. DOI: 10.1016/j.radphyschem.2020.108710

    Abstract: The high activity of spent cartridge filters from the cooling water polishing system of a nuclear research reactor precludes, in routine work of a waste characterization program, the usual method of radiochemical analysis of filter samples. For this waste, the dose-to-activity method, using a gamma spectrometer and a dose rate meter, is an alternative for the determination of the activities of the gamma emitters with acceptable accuracy. The ratio of photon peak-areas from different radionuclides, corrected by the detector energy-dependent efficiency, allowed estimating the proportions between the activities of the different radionuclides present. Finally, the simulation of the counting geometry, using the point-kernel method to estimate the air dose rate resulting from an arbitrary concentration of those radionuclides and the comparison of the calculated with the measured air dose rate have yielded the needed estimates of the activity concentrations. The aim of this paper is to report the development of the method applied for the determination of the concentration of the gamma-emitters present in cartridge filters from the IEA-R1 Nuclear Research Reactor.

    Palavras-Chave: radioactive waste management; calculation methods; radioisotopes; gamma spectrometers; filters; iear-1 reactor; inventories; solid wastes; dose rates

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  • IPEN-DOC 26877

    SCHELL, J.; DANG, T.T.; CARBONARI, A.W. . Incorporation of Cd-doping in SnO2. Crystals, v. 10, n. 1, p. 1-7, 2020. DOI: 10.3390/cryst10010035

    Abstract: Tuning the electrical properties of materials by controlling their doping content has been utilized for decades in semiconducting oxides. Here, an atomistic view is successfully employed to obtain local information on the charge distribution and point defects in Cd-doped SnO2. We present a study that uses the time-di erential perturbed gamma–gamma angular correlations (TDPAC) method in samples prepared by using a sol–gel approach. The hyperfine field parameters are presented as functions of the annealing temperature in pellet samples to show the evolution of incorporating Cd dopants into the crystal lattice. Additionally, the system was characterized with X-ray fluorescence, electron dispersive spectroscopy, and scanning electron microscopy after the probe nuclei 111In(111Cd) decayed. The TDPAC results reveal that the probe ions were incorporated into two di erent local environments of the SnO2 lattice at temperatures up to 973 K for cation substitutional sites.

    Palavras-Chave: doped materials; tin oxides; stannates; gamma cascades; angular correlation; perturbed angular correlation; sol-gel process; gamma spectrometers; semiconductor materials; oxides

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  • IPEN-DOC 26875

    GROSSO, ROBSON L. ; MUCCILLO, ELIANA N.S. ; MUCHE, DERECK N.F.; JAWAHARRAM, GOWTHAM S.; BARR, CHRISTOPHER M.; MONTERROSA, ANTHONY M.; CASTRO, RICARDO H.R.; HATTAR, KHALID; DILLON, SHEN J.. In situ transmission electron microscopy for ultrahigh temperature mechanical testing of ZrO2. Nano Letters, v. 20, n. 2, p. 1041-1046, 2020. DOI: 10.1021/acs.nanolett.9b04205

    Abstract: This work demonstrates a novel approach to ultrahigh-temperature mechanical testing using a combination of in situ nanomechanical testing and localized laser heating. The methodology is applied to characterizing and testing initially nanograined 10 mol % Sc2O3-stabilized ZrO2 up to its melting temperature. The results suggest that the low-temperature strength of nanograined, d < 50 nm, oxides is not influenced by creep. Tensile fracture of ZrO2 bicrystals produce a weak-temperature dependence suggesting that grain boundary energy dominates brittle fracture of grain boundaries even at high homologous temperatures; for example, T = 2050 °C or T ≈ 77% Tmelt. The maximum temperature for mechanical testing in this work is primarily limited by the instability of the sample, due to evaporation or melting, enabling a host of new opportunities for testing materials in the ultrahigh-temperature regime.

    Palavras-Chave: transmission electron microscopy; ultrahigh temperature; materials testing; mechanical properties; crystals; nanostructures; zirconium oxides; grain boundaries

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  • IPEN-DOC 26874

    CAMARGO, V.F. de ; FONTES, E.H. ; NANDENHA, J. ; SOUZA, R.F.B. de ; NETO, A.O. . High activity of Pt–Rh supported on C–ITO for ethanol oxidation in alkaline medium. Research on Chemical Intermediates, v. 46, n. 2, p. 1555-1570, 2020. DOI: 10.1007/s11164-019-04050-5

    Abstract: PtRh/C–ITO electrocatalysts were prepared in a single-step method using H2PtCl6 ·6H2O and RhCl3 ·xH2O as metal sources, sodium borohydride as the reducing agent and a physical mixture of 85% Vulcan Carbon XC72 and 15% In2O3 ·SnO2 (indium tin oxide—ITO) as support. PtRh/C–ITO were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry, chronoamperommetry, attenuated total reflectance, Fourier transform infrared spectroscopy and performance test on direct alkaline ethanol fuel cell. X-ray diffraction patterns for all PtRh/C–ITO indicated a shift in Pt (fcc) peaks, showing that Rh was incorporated into Pt lattice. Transmission electron microscopy for PtRh/C–ITO showed nanoparticles homogeneously distributed over the support with particles size between 3.0 and 4.0 nm. The XPS results for Pt70Rh30/C–ITO showed the presence of mixed oxidation states of Sn0 and SnO2 that could favor the oxidation of adsorbed intermediates by bifunctional mechanism. Pt90Rh10/C–ITO was more active in electrochemical studies, which could be associated with the C–C bond break. Experiments in direct alkaline ethanol fuel cells showed that the power density values obtained for Pt70Rh30/C–ITO and Pt90Rh10/C–ITO were higher than Pt/C, indicating the beneficial effect of Rh addition to Pt and the use of C–ITO support.

    Palavras-Chave: sodium compounds; borohydrides; ethanol; oxidation; reduction; indium oxides; tin oxides; fourier transform spectrometers; fourier transformation

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  • IPEN-DOC 26873

    SANTOS, DOUGLAS C.; GOES, JOÃO M.R.; SOUZA, VIVIANE C. de; BISPO, DIEGO F.; OTUBO, LARISSA ; ANDRADE, GEORGE R.S.; CAMARGO, ZAINE T.; SANTOS, EULER A. dos. Green synthesis of silver nanostructures with amino acid-modified Pluronic F127 for antibacterial applications. Applied Surface Science, v. 505, p. 1-12, 2020. DOI: 10.1016/j.apsusc.2019.144449

    Abstract: The aim of this work was to evaluate the use of amino acid-functionalized Pluronic F127 derivatives in the synthesis of silver nanostructures (SNS), such as nanoparticles (SNP) and nanoclusters (SNC). Herein, glycine, Lalanine, and DL-alanine were used to functionalize poly(ethylene oxide) (PEO) end groups from the polymer chain via an esterification pathway. The esterified polymers were used for reducing and stabilizing SNS by a hydrothermal or a photo-assisted route (using a UVA light). The functionalized polymers were characterized by FTIR and the obtained SNS were characterized by UV–vis spectroscopy and TEM, which showed that the SNS obtained by the hydrothermal route are predominantly spherical, whereas those obtained by photo-assisted method give rise to rods and prisms. Kinetic studies showed that alanine and glycine form particles with different rates and that the different enantiomers (L and DL) influence the size and shape of SNS. The nanoparticles obtained by the two routes had their antibacterial efficiency tested against S. aureus by the Agar well diffusion method.

    Palavras-Chave: nanoparticles; silver; nanostructures; pluronics; synthesis; antibiotics; amino acids; alanines; reduction; photochemistry

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  • IPEN-DOC 26872

    SARAIVA, CRYSTIAN W.C.; CARDOSO, SIMONE C.; GROPPO, DANIELA P. ; SALLES, ANTONIO A.F. de; AVILA, LUIZ F. de; ROSA, LUIZ A.R. da. Gamma Knife radiosurgery for vestibular schwannomas: evaluation of planning using the sphericity degree of the target volume. PLoS One, v. 15, n. 1, p. 1-18, 2020. DOI: 10.1371/journal.pone.0225638

    Abstract: Introduction This study explores the possibility of a relationship between the sphericity degree of a target volume with the dose distribution. This relationship is evaluated based on the ratio isodose volume / target volume (IV/TV) and the metrics coverage, i.e., selectivity, gradient index, conformity index and mean dose when planning radiosurgery for vestibular schwannoma. Methods Sphericity degree (φ) was calculated for each target volume (TV) of 64 patients who underwent stereotactic radiosurgery (SRS) for vestibular schwannoma. The calculation of this parameter was developed using the theoretical definition for operational sphericity φ = VP/ VCS. The values found are evaluated considering the following metrics:—Coverage (C), selectivity (S), gradient index (GI), Paddick conformity index (CIPaddick) and dose distribution (IV/TV). The planning was also carried out considering a spherical target volume defined in a spherical phantom. The spherical volume is the same as the target used in the treatment plan. The planning of the spherical target was considered as a reference plan to evaluate the dose distribution inside and outside the volume. Results It was possible to observe that the majority of target volumes has (ϕ) around 0,66–0,77, corresponding to 54,7% of the total. Considering the mean values for metrics, the results are: C = 0,98, S = 0,78, GI = 3,11 and CI = 0,81. The dose distribution was equivalent for treatment plans and reference plans. Quantitative analysis for IV/TV shows that these values are higher than 30% for treatment plans where shot density is large. Conclusion This study demonstrates that de sphericity degree (φ) can be related to the dose distribution (IV/TV). Therefore the sphericity degree is a good parameter to evaluate the dose distribution of a plan for vestibular schwannoma treatment, considering the reference plan as being a spherical target using a leksell gamma knife® perfexion (LGKP). This study shows that the sphericity degree offers important information of the dose distribution outside and inside the target volume. This is not evaluated by the other parameters already implemented as metric to analyzing the GKP plans.

    Palavras-Chave: neoplasms; radiotherapy; surgery; gamma radiation; vestibular apparatus; therapy; radiation doses; isodose curves

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  • IPEN-DOC 26871

    TINTI, VICTOR B.; MARANI, DEBORA; FERLAUTO, ANDRE S; FONSECA, FABIO C. ; ESPOSITO, VINCENZO; FLORIO, DANIEL Z. de. Exsolution of nickel nanoparticles from mixed-valence metal oxides: a quantitative evaluation by magnetic measurements. Particle and Particle Systems Characterization, v. 37, n. 2, p. 1900472-1 - 1900472-7, 2020. DOI: 10.1002/ppsc.201900472

    Abstract: A fast and accurate experimental method is demonstrated to assess the fraction of exsolved metallic nanoparticles using magnetic measurements. As a benchmark, nanometric metallic nickel exsolved from (La1−xSrx)(Cr1−yNiy) O3−δ is used for its high relevance as a solid oxide fuel cell component. The method is based on the difference in the magnetic response of the exsolved metallic nickel (ferromagnetic) and Sr-doped lanthanum chromite ceramic matrix (paramagnetic). The exsolved nickel results in coherent nanoparticles pinned on the surface of the Sr-doped lanthanum chromite ceramic matrix, as evidenced by electron microscopy analyses. The results obtained indicate the procedure as a fast and sensitive method to study the exsolution of ferromagnetic nanoparticles.

    Palavras-Chave: nanoparticles; nickel; magnetic fields; magnetometers; valence; evaluation; ferromagnetic materials

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  • IPEN-DOC 26870

    CARVALHO, L.R. de ; VIEIRA, D.P. . Evaluation of genotoxic potential of peptides used in nuclear medicine (PSMA -617 and -11, and ubiquicidine 29-41) using a flow-cytometric, semi-automated analysis of micronuclei frequency in cell cultures. Toxicology Reports, v. 7, p. 304-316, 2020. DOI: 10.1016/j.toxrep.2020.02.003

    Abstract: Assays that rely on the assessment of frequency of micronuclei are important standard techniques currently used to quantify potential genotoxic damage after exposure to chemical or physical agents, such as ionizing radiation, or in pre-clinical studies, to assessment of the genotoxic potential of drugs or its components. The experiments are usually performed using conventional microscopy, but currently the protocols are being upgraded to automated approaches based on flow cytometry protocols based on the elimination of the plasma membrane by chemical agents, allowing quantification by flow cytometry. In this work, the genotoxic potential of peptides used as components of radiopharmaceuticals (PSMA-617 and 11 and Ubiquicidine) was evaluated exposing CHO-KI cells to a wide range of concentration (0.1X and 100X the maximum allowed concentration to human adults). Incubation with PSMA-11 or UBI29–41 did not induce genotoxicity. After 24 h of incubation, PSMA-617 induced genotoxicity only in non-practical concentration (100-fold). Results corroborate the safety of the predrugs and the wide detection range of technique.

    Palavras-Chave: radiopharmaceuticals; toxicity; antigens; peptides; antimicrobial agents; cell cultures; cell flow systems; ionizing radiations

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  • IPEN-DOC 26869

    DE LEO, THAIS C.; SANTOS, SOFIA N. dos ; ANDRADE, CAMILLO D.C.; RICCI, EDUARDO; TURATO, WALTER M.; LOPES, NORBERTO P.; OLIVEIRA, RALPH S.; BERNARDES, EMERSON S. ; DIAS-BARUFFI, MARCELO. Engineering of galectin-3 for glycan-binding optical imaging. Biochemical and Biophysical Research Communications, v. 521, n. 3, p. 674-680, 2020. DOI: 10.1016/j.bbrc.2019.10.161

    Abstract: Galectin-3 (Gal-3) is a multifunctional glycan-binding protein that participates in many pathophysiological events and has been described as a biomarker and potential therapeutic target for severe disorders, such as cancer. Several probes for Gal-3 or its ligands have been developed, however both the pathophysiological mechanisms and potential biomedical applications of Gal-3 remain not fully assessed. Molecular imaging using bioluminescent probes provides great sensitivity for in vivo and in vitro analysis for both cellular and whole multicellular organism tracking and target detection. Here, we engineered a chimeric molecule consisting of Renilla luciferase fused with mouse Gal-3 (RLuc-mGal-3). RLuc-mGal-3 preparation was highly homogenous, soluble, active, and has molecular mass of 65,870.95 Da. This molecule was able to bind to MKN45 cell surface, property which was inhibited by the reduction of Gal-3 ligands on the cell surface by the overexpression of ST6GalNAc-I. In order to obtain an efficient and stable delivery system, RLuc-mGal-3 was adsorbed to poly-lactic acid nanoparticles, which increased binding to MKN45 cells in vitro. Furthermore, bioluminescence imaging showed that RLuc-mGal-3 was able to indicate the presence of implanted tumor in mice, event drastically inhibited by the presence of lactose. This novel bioluminescent chimeric molecule offers a safe and highly sensitive alternative to fluorescent and radiolabeled probes with potential application in biomedical research for a better understanding of the distribution and fate of Gal-3 and its ligands in vitro and in vivo.

    Palavras-Chave: proteins; carbohydrates; bioluminescence; luciferase; tumor cells; lectins; molecular biology; probes; engineering; corals

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  • IPEN-DOC 26868

    CORREA, E.L. ; BOSCH-SANTOS, B. ; SAXENA, R.N. ; CABRERA-PASCA, G.A.; CARBONARI, A.W. . Effects of an external magnetic field on the hyperfine parameters in RE2O3 (RE = Gd, Er) nanoparticles measured by perturbed angular correlation spectroscopy. AIP Advances, v. 10, n. 1, p. 015039-1 - 015039-6, 2020. DOI: 10.1063/1.5130401

    Abstract: In order to understand the interaction mechanisms in RE2O3 (RE=Gd, Er) nanoparticles (NPs), Perturbed Angular Correlation (PAC) spectroscopy, a local technique, plus external magnetic field, was used to elucidate local interactions and possible mapping of the different contribution in these compounds. NPs were synthesized by thermal decomposition and characterized by transmission electron microscopy and X-ray diffraction. PAC measurements were performed using 111In(111Cd) as probe nuclei, with and without the application of an external magnetic field (EMF) of 0.5 T in different temperatures (50 K, 100 K, 200 K, 300 K). Results show that the hyperfine magnetic field is almost zero when the probe is located at the symmetric site, and ∼4 T and ∼5 T for Gd2O3 and Er2O3, respectively, when the probe occupies the asymmetric field.

    Palavras-Chave: perturbed angular correlation; spectroscopy; magnetic fields; rare earths; hyperfine structure; asymmetry coefficients; thermal analysis; transmission electron microscopy; x-ray diffraction

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  • IPEN-DOC 26867

    CABRERA-PASCA, G.A.; BOSCH-SANTOS, B. ; BURIMOVA, A. ; CORREA, E.L. ; CARBONARI, A.W. . Effect of the magnetic impurity on the charge diffusion in highly dilute Ce doped LaMnO3. AIP Advances, v. 10, n. 1, p. 015223-1 - 015223-5, 2020. DOI: 10.1063/1.5130429

    Abstract: LaMnO3+δ is a complex oxide, which, depending on the oxygen excess concentration, presents different crystalline structure and interesting magnetic and electric properties such as colossal magnetoresistance, polaron dynamics, multiferroic behavior, and charge-orbital ordering. This complexity requires different characterization techniques to draw a picture as complete as possible allowing a good understanding of these phenomena. Here, we have used the perturbed angular correlation (PAC) technique to measure hyperfine interactions at La and Mn sites of LaMnO3+δ(δ ∼0.15) using 140Ce and 111Cd at La sites as probe nuclei in order to investigate within an atomic scale the magnetic and electric interactions in this compound. The results show that 111Cd nuclei occupy highly symmetric local sites in agreement with a rhombohedral structure. The magnetic hyperfine field (Bhf ) measured with 111Cd at La sites is very small (Bhf = 0.40 T) due to the supertransferred magnetic field from Mn neighbors through oxygen orbitals. On the other hand, 140Ce nuclei at La sites present a saturation field of around 3.7 T much higher than that expected for La sites (due to the weak transfer field by superexchange mechanism). In addition, for temperature range above the magnetic ordering (200-300 K) a dynamic hyperfine interaction was observed characterized by the attenuation parameter λ(T) whose temperature dependence allowed to determine the activation energy (Ea) associated to charge transfer. The polarization of the 4f -electron of Ce impurities affects the local magnetic field at impurity sites as well as the Ea.

    Palavras-Chave: impurities; magnetic flux; doped materials; perturbed angular correlation; trigonal lattices; hyperfine structure; magnetic moments; cerium additions; lanthanum; thin films; manganese oxides; probes

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  • IPEN-DOC 26866

    FERREIRA JUNIOR, J.M.; RAJENDRAN, V.; SIMONELLI, G.; SILVA, A.C.M.; SANTOS, L.C.L.; MATTEDI, S.; PONTES, L.A.M.; COSTA, I. ; ROSSI, J.L. ; BAKER, M.A.. Deposition and characterization of a sol-gel Mg-substituted fluorapatite coating with new stoichiometries. Applied Surface Science, v. 505, p. 1-13, 2020. DOI: 10.1016/j.apsusc.2019.144393

    Abstract: The calcium substitution for magnesium on fluorapatite is attractive because this element is a natural substitute in biological apatites. There are several published stoichiometries for calcium substituted by magnesium fluorapatites and most works point out that the formation and fixation of biomimetic Ca-P coatings in Ringer’s solution were strongly related to Mg2+ content and furthermore the Mg replacement improves the bioactivity of apatite. In the present study, fluorapatite (FA) and fluorapatite substituted with 6% and 7% of magnesium were obtained by deposition via sol-gel coating on substrates of AISI 316L stainless steel to investigate the effect of magnesium substitution on fluorapatite with not yet investigated stoichiometry. Characterization of coating thickness, chemical composition and crystalline structure was performed using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The coating adhesion was evaluated using the pull-out test and the corrosion resistance was undertaken using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The electrochemical results showed improvement in the corrosion resistance of magnesium-fluorapatite compared to fluorapatite coated on AISI 316L stainless steel substrates. The improvement corrosion protection and adhesion performance indicate that such magnesium fluorapatites coatings are very interesting candidates as bioactive coatings for implants.

    Palavras-Chave: stoichiometry; apatites; biological materials; implants; magnesium; coatings; hydroxides; sol-gel process; corrosion

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  • IPEN-DOC 26865

    BEZAMAT, JULIANA M.; YOKAICHIYA, FABIANO ; FRANCO, MARGARETH K.K.D. ; CASTRO, SIMONE R.; PAULA, ENEIDA de; CABEÇA, LUIS F.. Complexation of the local anesthetic pramoxine with hydroxypropyl-beta-cyclodextrin can improve its bioavailability. Journal of Drug Delivery Science and Technology, v. 55, p. 1-8, 2020. DOI: 10.1016/j.jddst.2019.101475

    Abstract: Local anesthetics are widely used in clinical procedures, to eliminate pain during/after invasive procedures. A wide range of drug delivery systems has been developed to improve the effect of local anesthetics and/or to reduce their toxicity. Pramoxine (PMX) is a topical anesthetic agent with an unusual (morpholine ring) structure and low solubility (ca. 3 mM at pH 7.4). In this work, a novel formulation was devised for PMX in hydroxypropyl- β-cyclodextrin (HP-β-CD). Host-guest inclusion complex was prepared by the co-solubilization method, with complexation kinetics of 10 h, and 1:1 PMX/HP-β-CD stoichiometry. Complexation promoted 14-fold increase in the solubility of PMX. X-ray diffraction measurements revealed loss of the crystalline PMX pattern in the presence of HP-β-CD, an indication of inclusion complexation. Using 1H NMR (DOSY) experiments the association constant of PMX to HP-β-CD (Ka = 923.1 mol/L) was determined, while nuclear Overhauser (ROESY) analysis confirmed the formation of PMX/HP-β-CD inclusion complex, by detection of spatial proximities between hydrogens from PMX aromatic ring and cyclodextrin's cavity. In two in vitro toxicity models (mouse 3T3 fibroblasts in culture and red blood cells hemolysis) pramoxine toxicity was significantly reduced upon complexation into HP-β-CD. These results point out PMX/HP-β-CD as a promising pharmaceutical formulation to improve the bioavailability of pramoxine, allowing its application beyond topical anesthesia.

    Palavras-Chave: anesthesia; oligosaccharides; complexes; anesthetics; clathrates; nuclear magnetic resonance; stoichiometry; antimitotic drugs; hemolysis; chemical composition

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  • IPEN-DOC 26864

    PARDO DIAZ, C.A.; SHIMOKAWA, C.A.K.; SAMPAIO, C.S.; FREITAS, A.Z. ; TURBINO, M.L.. Characterization and comparative analysis of voids in class II composite resin restorations by optical coherence tomography. Operative Dentistry, v. 45, n. 1, p. 71-79, 2020. DOI: 10.2341/18-290-L

    Abstract: Purpose: This study aimed to characterize and analyze the number of voids and the percentage of void volume within and between the layers of class II composite restorations made using the bulk fill technique or the incremental technique by optical coherence tomography (OCT). Methods and Materials: Class II cavities (43432 mm) were prepared in 48 human third molars (n=24 restorations per group, two class II cavities per tooth). Teeth were divided into four groups and restored as follows: group 1 (FOB), bulk filled in a single increment using Filtek One Bulk Fill (3M Oral Care); group 2 (FXT), incrementally filled using four oblique layers of Filtek Z350 XT (3M Oral Care); group 3 (FBF+FXT), bulk filled in a single increment using Filtek Bulk Fill Flowable Restorative (3M Oral Care) covered with two oblique layers of Filtek Z350 XT (3M Oral Care), and group 4 (FF+FXT), incrementally filled using Filtek Z350 XT Flow (3M Oral Care) covered with two oblique layers of Filtek Z350 XT (3M Oral Care). After the restorative procedure, specimens were immersed into distilled water and stored in a hot-air oven at 378C. Forty-eight hours later, thermal cycling was conducted (5000 cycles, 58C to 558C). Afterward, OCT was used to detect the existence of voids and to calculate the number of voids and percentage of voids volume within each restoration. Data were submitted to chi-square and Kruskal- Wallis tests (a=0.05). Comparisons were made using the Dunn method. Results: Voids were detected in all groups, ranging from 0.000002 (FBF+FXT and FF+FXT) to 0.32 mm3 (FBF+FXT). FF + FXT presented voids in all of the restorations and had a significantly higher number of voids per restoration when compared to the other groups (p,0.05), but restorations with the presence of voids were significantly higher only when compared to FXT (p,0.05). FBF + FXT presented a significantly higher percentage of voids volume than that of FXT (p,0.05). When comparing restorations made using high-viscosity resin-based composites (FOB and FXT), no significant differences regarding number of voids or percentage of voids volume were detected (p 0.05). Conclusions: The use of flowable resin-based composites can result in an increased number of voids and percentage of voids volume in restorations, and this appears to be more related to voids present inside the syringe of the material than to the use of incremental or bulk fill restorative techniques.

    Palavras-Chave: dentistry; resins; biological recovery; tomography; optical equipment; images; composite materials; voids; layers

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  • IPEN-DOC 26863

    BELLONI, MARCIO ; CONTI, THADEU das N. . Analysis of materials for heat transport in tokamaks. World Journal of Nuclear Science and Technology, v. 10, n. 1, p. 39-46, 2020. DOI: 10.4236/wjnst.2020.101005

    Abstract: Every nuclear power reactor, whether of fusion or fission, is essentially a thermal system that generates electricity. In this sense, there are several problems in relation to this heat transport. The model of plasma confinement by magnetic force, in the nuclear fusion (sterellator and tokamak), has only been 20 years and recently some success in the quality of the generated plasma has been achieved. However, due to the large amount of energy coming from the plasma, the choice of the material that will carry the generated energy is quite troublesome, due to the need to handle a very high temperature for the nuclear fission standards. Solutions are explored by the scientific community to transport the energy generated in the case of the primary circuit, after exceeding breakeven temperature and models that are based on the fission reactors of the fourth generation and those currently in operation, to search for solutions regarding the transport of heat generated for the generation of electric energy. Several materials such as pressurized water, sodium, helium and boron have been considered and studied to form the primary heat transfer circuit for the exchanger. A thorough analysis of these materials is necessary. This research looked at some of these materials for heat transport and power generation. Lithium and helium were found to be the probable materials for conveying heat and cooling in the blanket. The results show that research on blanket materials needs more attention. The quality of these materials needs to be improved by material research, with the ODS EUROFER alloy and other research to reduce material erosion by helium nano bubbles. Plasma quality needs to be improved to keep constant and free of impurities when using lithium in liquid form.

    Palavras-Chave: nuclear power; reactors; thermonuclear reactions; tokamak devices; renewable energy sources; iter tokamak; heating; heat transfer

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  • IPEN-DOC 26862

    GARCIA, PAULO R.A.F.; PRYMAK, OLEG; GRASMIK, VIKTORIA; PAPPERT, KEVIN; WLYSSES, WAGNER; OTUBO, LARISSA ; EPPLE, MATTHIAS; OLIVEIRA, CRISTIANO L.P.. An in situ SAXS investigation of the formation of silver nanoparticles and bimetallic silver–gold nanoparticles in controlled wet-chemical reduction synthesis. Nanoscale Advances, v. 2, n. 1, p. 225-238, 2020. DOI: 10.1039/c9na00569b

    Abstract: We present a study on the formation of silver (Ag) and bimetallic silver–gold (AgAu) nanoparticlesmonitored by in situ SAXS as well as by ex situ TEM, XRD and UV-vis analysis in a flow reactor at controlled reaction temperature. The formation mechanism of the nanoparticles is derived from the structural parameters obtained from the experimental data. The evolution of the average particle size of pure and alloyed nanoparticles shows that the particle growth occurs initially by a coalescence mechanism. The later growth of pure silver nanoparticles is well described by Ostwald ripening and for the alloyed nanoparticles by a process with a significantly slower growth rate. Additionally, the SAXS data of pure silver nanoparticles revealed two major populations of nanoparticles, the first one with a continuous crystal growth to a saturation plateau, and the second one probably with a continuous emergence of small new crystals. The particle sizes obtained by SAXS agree well with the results from transmission electron microscopy and X-ray diffraction. The present study demonstrates the capability of an in situ investigation of synthesis processes using a laboratory based SAXS instrument. Online monitoring of the synthesis permitted a detailed investigation of the structural evolution of the system.

    Palavras-Chave: nanoparticles; small angle scattering; x-ray diffraction; silver; bimetals; gold; monte carlo method; nanostructures; alloys

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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.

    Palavras-Chave: mercury; thyroid; thyroxine; selenium; chronic exposure; occupational exposure; blood serum

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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.

    Palavras-Chave: phosphate minerals; gypsum; rare earths; phosphate rocks; fertilizers; superphosphates; leaching; neutron activation analysis; soils; amendments; leachates; brazil

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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.

    Palavras-Chave: dispersions; films; gamma radiation; irradiation; methacrylates; nanocomposites; physical properties; polymerization; titanium oxides; x-ray diffraction

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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.

    Palavras-Chave: cobalt 60; cross-linking; dose rates; gamma radiation; irradiation; nanoparticles; papain; radiation doses; synthesis

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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.

    Palavras-Chave: electron beams; epoxides; ethylene propylene diene polymers; fourier transformation; infrared spectra; ionizing radiations; luminescence; protective coatings; radiation dose units; resins

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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.

    Palavras-Chave: machining; microstructure; texture; cutting; lasers

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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.

    Palavras-Chave: lasers; hardness; steels; microhardness

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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.

    Palavras-Chave: texture; machining; austenitic steels; stainless steels

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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.

    Palavras-Chave: lutetium 177; radiopharmaceuticals; prostate; neoplasms; brazil

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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... Vienna, Austria: International Atomic Energy Agency, 2020. p. 155-161. (IAEA-TECDOC-1913).

    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).

    Palavras-Chave: accident-tolerant nuclear fuels; charges; cladding; comparative evaluations; currents; fuel rods; fuel systems; fukushima daiichi nuclear power station; hazards; zircaloy 4; iron; loss of coolant; nuclear power plants; operation; performance; pwr type reactors; reactivity-initiated accidents; steady-state conditions; uranium dioxide

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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... Vienna, Austria: International Atomic Energy Agency, 2020. p. 95-101. (IAEA-TECDOC-1913).

    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.

    Palavras-Chave: accident-tolerant nuclear fuels; beryllium oxides; uranium dioxide; zircaloy; ceramics; cladding; cross sections; eutectics; fission product release; fission products; fuel cans; fuel pellets; fuel rods; fukushima daiichi nuclear power station; loss of coolant; mechanical properties; melting; mixed oxide fuels; performance; safety margins; simulation; thermal conductivity

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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.

    Palavras-Chave: alloys; copper; solidification; hardness; dendrites

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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. 136 p. Orientador: Letícia Lucente Campos Rodrigues. DOI: 10.11606/T.85.2020.tde-06022020-104210

    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.

    Palavras-Chave: structural models; phantoms; thermoplastics; organic compounds; animal tissues; radiation detectors; dose equivalents; dose-response relationships; acute exposure; biological radiation effects; performance testing; computerized simulation; digital systems; image processing; dosimetry; ionizing radiations; nuclear medicine; radiation protection

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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.

    Palavras-Chave: nuclear industry; nuclear power plants; reactor accidents; environmental policy; government policies; civil liability; nuclear liability; nuclear damage; brazil; environmental effects

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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.

    Palavras-Chave: phosphors; radiation detectors; crystal growth; neutron sources; lithium; doped materials; bridgman method; cesium iodides; optical properties; luminescence; spectra; radiation sources; crystal doping

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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.

    Palavras-Chave: radiation detectors; scintillation counters; phosphors; crystals; crystal doping; doped materials; bridgman method; neutrons; cesium iodides; gamma detection; alpha detection; beta detection; bromine; lead; thallium; lithium

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

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

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

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

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

Exemplo:

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

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

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

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

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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.

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

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

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

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