Reposiório IPEN: Recent submissions

  • IPEN-DOC 28004

    SAHYUN, ADELIA ; PEREZ, CLARICE A.. Real time tracking of mobile radioactive sources. In: INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 15th, January 18 - February 5, 2021, Seoul, Korea; Online. Seoul, 2021. p. 857-857.

    Abstract: It is vital that mobile radioactive sources remain under safe and secure control, at all times and the operator is notified in real time of their unauthorised removal from a fixed location, store or vehicle. This paper describes a system that constanily monitors mobile radioactive sources and provides a means to detect their location should unauthorised removal occur. Thousands of radiographic exposure devices are transported in the public domain every day and there are examples where the vehicle carrying a device has been stolen, not for the device itself but for the vehicle, which often leads to the device being discarded. Abandoning the device can lead to high risks of exposure for those who have secondary contact for example children or those attracted by its perceived intrinsic value. A lack of knowledge of the dangers of radiation has led some people in the past attempting and sometimes succeeding to open a device and remove the source. With other factors involved such as location, country and the intentions of those in possession of the device, it is therefore important that the device is located quickly, enabling recovery actions to begin as soon as possible. In addition, this paper encourages that such monitoring systems are more widely promoted in all countries and that an international code of practice is developed to assist when sources are transported internationally.

    Palavras-Chave: radiation sources; radiation monitoring; security; radiation protection

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  • IPEN-DOC 28020

    CORREIA, RUANYTO W. . Análise da pureza radioativa de iodo-125 produzido no reator nuclear IEA-R1 pelo método de espectrometria gama e comparação com a exigência internacional / Analysis of radioactive purity of iodine-125 produced in the nuclear reactor IEA-R1 by the gamma spectrometry method and comparison with the international requirement . 2021. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 53 p. Orientador: Carlos Alberto Zeituni. DOI: 10.11606/D.85.2021.tde-14072021-104200

    Abstract: Com a finalidade de otimizar a produção, a irradiação e a quantificação de iodo-125 utilizado na confecção de sementes de iodo para braquiterapia, uma metodologia teórico-experimental foi aplicada baseada no procedimento proposto por COSTA, O. L., 2015, em que iodo-125 é obtido via ativação neutrônica no reator nuclear IEA-R1 a partir da irradiação de xenônio-124 encapsulado em compartimentos de alumínio. Após todo o preparo das amostras seguindo o processo descrito, iniciou-se o processo de irradiação sob o fluxo de nêutrons da ordem de 1013 nêutrons.cm-2.s-1 por diferentes períodos de tempo. Foram irradiadas seis cápsulas (duas contendo Xe-124 natural e quatro contendo Xe-124 enriquecido 99,9%) a fim de comparar a atividade total produzida variando o parâmetro de enriquecimento da amostra. Depois de serem irradiadas, as capsulas foram abertas e lavadas em meio alcalino aquecido para extração do iodo depositado nas paredes internas. As soluções geradas foram armazenadas em diferentes frascos padrões de acrílico, nomeadas e quantificadas via espectrometria gama com Detector de Germânio Hiperpuro (HPGe ORTEC modelo GEM-C5970-B) para determinação da pureza do radionuclídeo de interesse. Para calibração do HPGe foi aplicada uma metodologia experimental utilizando uma fonte de calibração certificada de bário-133 com atividade bem conhecida em que as eficiências dos fotopicos energéticos foram medidos entre 0 - 667 keV. As curvas de eficiência foram determinadas para uma faixa de energia que cobrissem toda a região de interesse espectral para o iodo-125 e seus subprodutos gerados na reação nuclear, além disso, elas foram construídas para diferentes distâncias da janela do detector e dimensões do frasco padrão de análise. No processo de ativação, iodo-126 foi formado como subproduto indesejado, esse radionuclídeo foi quantificado e sua atividade determinada. Finalmente, foi possível determinar a pureza radionuclídica do iodo-125 e compará-la com as exigências internacionais de qualidade que regulam a produção de medicamentos radioativos.

    Palavras-Chave: ge semiconductor detectors; gamma dosimetry; gamma spectroscopy; radiopharmaceuticals; iodine 125; iodine 126; xenon 124; barium 133; brachytherapy; radiotherapy; isotope ratio; isotope applications; isotope production reactors; iear-1 reactor; coefficient of performance; efficiency

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  • IPEN-DOC 28019

    SILVA, RODRIGO P. da . Desenvolvimento de membranas não fluoradas a base de PBI para aplicação em células a combustível de etanol direto de alta temperatura / Development of non-fluorinated PBI-based membranes for application in high temperature direct ethanol fuel cells . 2021. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 96 p. Orientador: Elisabete Inácio Santiago. DOI: 10.11606/D.85.2021.tde-18082021-145926

    Abstract: A maioria das células a combustível de membrana de troca protônica (PEMFC) utiliza o Nafion® como eletrólito. Como possui um mecanismo de condução de prótons dependente de moléculas de água, estas células têm uma temperatura de operação limitada até 80°C. O aumento da temperatura de operação de uma célula PEMFC é desejado devido à contribuição da temperatura na aceleração das reações eletroquímicas, que são processos termoativados. Neste contexto, as membranas PBI (polibenzimidazol) dopadas com ácido fosfórico têm sido consideradas um polímero base bastante promissor para eletrólitos sólidos operantes em alta temperatura, devido à combinação de condução de prótons satisfatória em condições de baixa umidade relativa e excelente estabilidade térmica. No entanto, membranas baseadas em PBI apresentam algumas desvantagens, tais como lixiviação do ácido (veículo condutor), diminuição de sua resistência mecânica, permeabilidade aos combustíveis utilizados em PEMFC operante em alta temperatura (HT-PEMFC), permitindo que uma parte migre do ânodo para o cátodo da célula (crossover) e diminuindo assim a eficiência e o desempenho global do dispositivo. Neste contexto, o objetivo do trabalho foi o desenvolvimento e otimização de membranas compósitas a base de PBI e óxido de silício (SiO2), que além de atuar como reforço mecânico, pode contribuir na mitigação do crossover e, dessa forma, se apresentar como uma alternativa ao Nafion como eletrólito sólido em células a combustível de etanol direto de alta temperatura (HT-DEFC). Nesse sentido, membranas puras de PBI e compósitos PBI-SiO2 com diferentes frações de SiO2 (2,5%, 5%, e 10%) foram sintetizadas e caracterizadas por Raman, termogravimetria, microscopia eletrônica de varredura e espectroscopia de impedância eletroquímica. Por fim, as membranas foram avaliadas em protótipos de HT-DEFC a 180°C após parametrização e otimização dos componentes dos conjuntos eletrodos-membranas (MEA). Ainda, eletrocatalisadores anódicos baseados em Pt/C, PtSn/C e PtRu/C foram estudados com o objetivo de avaliar o efeito da natureza do catalisador no desempenho de HT-DEFCs.

    Palavras-Chave: electrocatalysts; direct ethanol fuel cells; proton exchange membrane fuel cells; high-temperature fuel cells; electrodes; fuel assemblies; pbi; silicon oxides; mechanical properties; optimization; raman spectroscopy; electric impedance; thermal gravimetric analysis

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  • IPEN-DOC 28018

    MIRANDA, ANA C.C. . Desenvolvimento de radioimunoconjugados como agentes teranósticos baseados no anticorpo monoclonal anti-HER2 (trastuzumabe) : influência dos agentes quelantes e dos radionuclídeos nas propriedades biológicas / Development of radioimmunoconjugates as theranostic agents based on the anti-HER2 monoclonal antibody (trastuzumab): influence of chelating agents and radionuclides on biological properties . 2020. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 165 p. Orientador: Elaine Bortoleti de Araújo. DOI: 10.11606/T.85.2020.tde-23062021-162032

    Abstract: O câncer de mama é a segunda maior causa de mortalidade no mundo. Os tumores HER2 positivos ocorrem em 20 a 30% dos casos de câncer de mama e podem ser caracterizados como sendo o segundo pior prognóstico em relação aos demais subtipos. Constitui um indicador de comportamento clínico mais agressivo e com pior resposta às terapêuticas convencionais. Nesse contexto, o desenvolvimento de técnicas de imagem não invasivas utilizando anticorpos monoclonais (AcM) é um campo em rápido desenvolvimento. Devido à elevada afinidade pelo receptor HER2, o AcM humanizado trastuzumabe tem sido alvo de estudos de radiomarcação com o intuito de radioimunodiagnóstico (RID) e radioimunoterapia (RIT). Levando-se em consideração a possível influência dos agentes quelantes bifuncionais, da razão molar anticorpo:quelante e dos radionuclídeos, nas propriedades físico-químicas e biológicas do radioimunoconjugado (RIC), este trabalho teve por objetivo desenvolver e comparar o potencial teranóstico do trastuzumabe-DTPA-111In e do trastuzumbe-DOTA-177Lu. Os resultados evidenciaram que os diferentes agentes quelantes, razões molares e radionuclídeos não influenciaram nas seguintes propriedades: integridade e estabilidade dos imunoconjugados; processo de radiomarcação e estabilidade dos RICs, estabilidade em soro, ligação às proteínas séricas, internalização e imunorreatividade. Em contrapartida, observou-se influência no caráter lipofílico dos RICs, na ligação às células que expressam receptores HER2, no perfil de biodistribuição e na captação tumoral. Estes dados permitem concluir que, em nível nacional, o trastuzumabe-DTPA-111In e o trastuzumabe-DOTA-177Lu é um par teranóstico com potencial aplicação em futuros estudos clínicos (RID e RIT) de cânceres que superexpressam receptores de HER2, em especial, o câncer de mama.

    Palavras-Chave: neoplasms; mammary glands; tumor cells; irradiation procedures; indium 111; lutetium 177; radioisotopes; radiopreservation; monoclonal antibodies; chemotherapy; drugs; injection; patients; clone cells; hybridomas; radioimmunoscintigraphy; radioimmunotherapy; radioimmunodetection; biological recovery; chelating agentes; stability; testing; in vitro; in vivo; animal tissues; rats

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  • IPEN-DOC 28017

    TERRA, BRUNA M. . Caracterização da etapa de estabilização do processo produtivo de fibra de carbono a partir de poliacrilonitrila utilizando algoritmos inteligentes / Characterization of polyacrylonitrile thermal stabilization process for carbon fiber production using intelligent algorithms . 2021. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 86 p. Orientador: Roberto Navarro de Mesquita. DOI: 10.11606/D.85.2021.tde-23062021-144310

    Abstract: Nos últimos anos, os materiais compósitos vêm expandindo, cada vez mais, sua aplicação em diversos segmentos, e em especial, os materiais compósitos poliméricos reforçados com fibra de carbono, demonstram ser um material estrutural de elevado desempenho que combina baixa massa específica e estabilidade mecânica. A produção de fibra de carbono, utilizando a poliacrilonitrila como precursor, possui diversas etapas em sequência: polimerização, fiação, estabilização térmica, carbonização e tratamento superficial. Em função da elevada duração e da importância das reações que ocorrem durante a estabilização, esta é considerada a etapa mais crítica do processo, na qual ocorre a formação do anéis aromáticos que influenciam diretamente na estrutura final da fibra de carbono e, consequentemente, na qualidade deste material. Visando otimizar o desenvolvimento deste material, bem como obter a redução do custo de produção, o presente trabalho realizou a modelagem computacional da etapa de estabilização térmica utilizando algoritmos inteligentes. Para obter o modelo, foi realizada uma prévia análise qualitativa utilizando as variáveis de processo e de qualidade dos materiais envolvidos na produção destas fibras. Esta análise inicial utilizou Mapas Auto-Organizáveis, a qual baseia-se em um treinamento não-supervisionado desta rede neural artificial. Posteriormente, foi utilizado treinamento supervisionado em uma rede neural feed-forward com retropropagação (backpropagation) para a análise quantitativa. A partir destas análises, foi possível simular a etapa de estabilização térmica de uma planta, em escala laboratorial, de produção de fibra de carbono, obtendo-se resultados com erros relativos de 2,98±0,01% e 2,48±0,02% para os parâmetros de Densidade Volumétrica e do Índice de Conversão por Espectrometria por Infravermelho com Transformada de Fourier (FTIR), quando comparados com os resultados experimentais.

    Palavras-Chave: graphite; production; mechanical properties; stability; thermal testing; stabilization; calorimetry; organic nitrogen compounds; composite materials; polymerization; nitriles; neural networks; artificial intelligence; algorithms; compactification

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  • IPEN-DOC 28016

    ALVES, NATHALIA Z. . Estudo in vitro para determinação de protocolo de irradiação para remoção de facetas cerâmicas em esmalte dental com laser de Er,Cr:YSGG / In vitro study to determine the irradiation protocol for removing ceramic veneers in dental enamel with an Er,Cr:YSGG . 2021. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 121 p. Orientador: Denise Maria Zezell. DOI: 10.11606/D.85.2021.tde-16062021-160748

    Abstract: A reabilitação estética por meio de facetas cerâmicas tornou-se prática frequente nas clínicas odontológicas. Contudo sua substituição, por diversos motivos, pode-se fazer necessária O uso do laser pode facilitar essa remoção quando necessária. Este trabalho tem como objetivo elaborar um protocolo para remover facetas cerâmicas sem causar danos à estrutura pulpar através da avaliação da irradiação com laser de Er,Cr:YSGG pulsado, bem como analisar se estes parâmetros causam alguma alteração morfológica, química ou óptica nos prismas de esmalte e se o aumento de temperatura ultrapassa 5,5 °C e 11 °C, valores esses que poderiam gerar danos a polpa e aos ligamentos periodontais, respectivamente. Na primeira parte do experimento foram preparados 180 fragmentos de dentes humanos que foram distribuídas aleatoriamente em 12 grupos experimentais (N=15), sendo 6 grupos irradiados e 6 grupos controle. Para a colagem das facetas cerâmicas de dissilicato de lítio com 0,7 mm utilizamos três diferentes cimentos resinosos (Variolink Veneer, RelyX U200 e RelyX Veneer). O cimento Rely X U200 não é um cimento resinoso preconizado pelo fabricante para s cimentação de facetas, mas mesmo assim o utilizamos, para remover quaisquer dúvidas relacionadas à alteração morfológica ocorrida no esmalte devido ao condicionamento ácido. O laser de Er,Cr:YSGG (2,78 μm) foi usado em dois protocolos de irradiação: 3,5 W; 48,14 J/cm2; 20 Hz, sem contato e 3,0 W de potência média; 40J/cm2 de densidade de energia e taxa de repetição de 20 Hz, sem contato e após a irradiação realizamos cisalhamento em todas as amostras. As análises morfológicas, ópticas e elementares do esmalte foram realizadas antes da cimentação e após a remoção, utilizando microscopia eletrônica de varredura (MEV), tomografia de coerência óptica (OCT) e espectroscopia de fluorescência de raios X de energia dispersiva (EDS). Na segunda parte do experimento foram utilizados 60 dentes humanos (incisivos inferiores) e estes foram distribuídos aleatoriamente em 12 grupos experimentais (N=5), sendo 6 grupos irradiados a laser e 6 grupos controle (remoção com instrumento rotatório diamantado), nos quais realizamos a análise de temperatura durante a remoção das facetas por ambos os métodos. O nível de significância estatística adotado foi de 5%. As medidas por EDS, após a remoção das facetas, revelaram um aumento significativo na quantidade de silício e carbono, bem como uma diminuição no conteúdo de cálcio e fosfato. A análise morfológica mostrou alteração dos prismas do esmalte nos grupos no quais foram utilizados os cimentos RelyX Veneer e Variolink Veneer, sendo esta alteração não decorrente da irradiação com laser. Apesar de não observamos alterações morfológicas nos prismas de esmalte, ocorreu aumento no coeficiente de atenuação óptica em dois grupos. Para avaliar o tipo de fratura que ocorreu no momento do cisalhamento, utilizamos as imagens geradas pelo MEV em um aumento de 50X e realizamos um teste de concordância intra-avaliador, Kappa = 0,951, e observamos que nos grupos com irradiação a laser de 3W as fraturas foram predominantemente do tipo adesiva. Nos grupos com irradiação a laser de 3,5W as fraturas foram predominantemente do tipo coesiva e nos grupos controles observamos uma variação entre os 3 padrões de fratura variando confirme o tipo de cimento resinoso, sendo que nos grupos CRU3 e CRU3,5 nenhuma fratura coesiva ocorreu. A análise de temperatura constatou que o uso de instrumento rotatório diamantado apresentou valores estatisticamente maiores quando comparados com a remoção a laser. Conclui-se que o laser de Er,Cr:YSGG é eficaz para remover laminados de dissilicato de lítio sem causar danos aos prismas de esmalte.

    Palavras-Chave: dentin; teeth; dentistry; layers; coatings; ceramics; coherent radiation; lasers; in vitro; thermal analysis; shear; microhardness; performance testing

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  • IPEN-DOC 28003

    PEREZ, CLARICE de F.A.; SAHYUN, A. . ALARA in focus. In: INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 15th, January 18 - February 5, 2021, Seoul, Korea; Online. Seoul, 2021. p. 645-645.

    Abstract: By the 1950s the world had already realized the need to protect the people from the harmful effects of ionizing radiation. In 1955 ICRP established an incipient dose limitation system that has since been refined over the years. The development of the fundamental philosophy was completed in the ICRP Publication 26, in 1977, where the three principles of the dose limitation system were established and identified separately. The principles are known as: (a) justification, (b) optimization or (ALARA) As Low As Reasonably Achievable, and (c) dose limitation. The philosophy contained in Publication 26 was adopted by the IAEA in its Safety Series publication No. 9, 1982 edition, and in Brazil by the National Nuclear Energy Commission in 1988, with the publication of the regulations CNEN-NE3.01. The three principles remain valid and in the current editions of both documents. This paper describes the development of the ALARA concept from its origin to the present day, to provide an insight and understanding of its meaning and importance for the new generations of Radiation Protection Supervisors and other professionals who work directly and indirectly in areas that involve the use of ionizing radiation.

    Palavras-Chave: alara; radiation protection; radiation doses; security; dose limits

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  • IPEN-DOC 28015

    SOBREIRO JUNIOR, ADALBERTO R. . Desenvolvimento de um plano preliminar de descomissionamento de um navio com uma planta de potência nuclear embarcada / Development of a preliminary proposal for a nuclear power-plant ship decommissioning . 2021. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 100 p. Orientador: Delvonei Alves de Andrade. DOI: 10.11606/D.85.2021.tde-16062021-154737

    Abstract: Para reduzir as emissões de gases do efeito estufa por navios mercantes, o emprego de energia nuclear seria uma opção viável, porém o descomissionamento traz custos elevados os quais impactam a viabilidade econômica. A experiência da Marinha Americana indica que o custo de um descomissionamento, depois de estabelecido um processo bem definido, é próximo de 25% do custo do reator, porém a experiência da Marinha Britânica, que protelou o descomissionamento, salienta um custo muito maior, ou seja, um bom planejamento reduz custos e atrasos. Portanto, é importante desenvolver uma boa política de reciclagem após a inativação do navio com uma usina nuclear. O objetivo deste trabalho é propor um método de descomissionamento para navios com propulsão nuclear através de pesquisas trazendo a experiência e feedback de outros países sobre esse assunto. Além de um processo enxuto de descomissionamento que atende as normas vigentes, este trabalho identificou requisitos de projeto e de base que trariam benefícios econômicos a um empreendimento nuclear. O potencial máximo de ganho com a adoção do método proposto e o atendimento dos requisitos identificados seria de 10,3% de economia sobre o preço da tarifa da energia vendida ao consumidor. No entanto, existem custos adicionais no projeto, cuja estimativa, às vezes, é de difícil obtenção.

    Palavras-Chave: mobile reactors; ship propulsion reactors; nuclear facilities; nuclear engineering; decommissioning; regulations; multilateral agreements; nuclear ships

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  • IPEN-DOC 28014

    SCHENEMANN, GISIELE . Avaliação da concentração de metais, elementos terras raras e traço presentes em perfis de sedimentos em reservatórios, estado de São Paulo / Metal, rare earth and trace elements evaluation in sediment profiles of reservoirs, São Paulo state . 2021. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 218 p. Orientador: Déborah Inês Teixeira Fávaro. DOI: 10.11606/D.85.2021.tde-16062021-153140

    Abstract: No presente estudo, perfis sedimentares dos reservatórios Taiaçupeba e Billingsbraço do Ribeirão Taquacetuba, inseridos na UGRHI-6; o reservatório do Córrego Marinheirinho, na UGRHI-15 e o reservatório do Lobo-Broa, UGRHI-13, foram avaliados. Os perfis sedimentares foram coletados nos anos de 2016 e 2017 pela CETESB, a diferentes profundidades e fatiados a cada 2,5 cm in situ. Elementos maiores, traço e terras raras (ETR - Ce, Eu, La, Lu, Nd, Sm, Tb e Yb) foram determinados pela técnica de Análise por Ativação Neutrônica Instrumental (INAA). A determinação da concentração de metais e semimetais (Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, P, Pb, Sc e Zn) foi realizada pela CETESB, pela técnica de espectrometria de emissão ótica com plasma indutivamente acoplado (ICP OES). A avaliação da qualidade dos sedimentos em relação aos metais tóxicos Cd, Cr, Cu, Hg, Pb, Ni e Zn e metaloide As, foi feita pela comparação aos valores guias do Environmental Canada (TEL e PEL) e adotados pela CETESB. Foram utilizadas também as ferramentas de fator de enriquecimento (FE) e o índice de geoacumulação (IGeo), para avaliação dos níveis de poluição antrópica para os demais elementos analisados, a partir da transição sedimentar rio-reservatório. Para os ETR, verificou-se o padrão de distribuição e a normalização em relação ao PAAS (Pos Archean Australian Shale). O reservatório Taiaçupeba apresentou contribuição antrópica de Br, Cu, Fe, Hg e Zn e o reservatório Billings-braço Taquacetuba, Br, Cd, Co, Cr, Hg, Ni, Mn e P em seus perfis sedimentares, a partir de suas construções até os dias atuais; o reservatório Marinheirinho apresentou um baixo enriquecimento de Al, Cs, Cu, Hg, Sb e Zn e o reservatório Lobo-Broa, de As, Cd, Na e P e moderado de Sc e Zn, porém ambos os reservatórios se mostraram mais preservados. Para os ETR, não foi observada nenhuma contribuição antrópica nos perfis sedimentares. O presente estudo mostrou a importância da análise dos perfis sedimentares verticais, pois trazem informações a respeito do histórico de contaminação dos reservatórios, permitindo distinguir os sedimentos superficiais (mais recentes) de seus sedimentos mais antigos e, também, as concentrações geogênicas e as antrópicas, a partir de suas construções.

    Palavras-Chave: sediments; alluvial deposits; surface waters; water reservoirs; water pollution monitors; granular materials; rare earths; toxicity; materials testing; computer calculations; neutron activation analyzers

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  • IPEN-DOC 28002

    LEVY, DENISE ; SORDI, GIAN M.A.A. . Risk perception and risk acceptance: the need of effective communications to fill the critical gaps between society and the scientific community. In: INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 15th, January 18 - February 5, 2021, Seoul, Korea; Online. Seoul, 2021. p. 116-116.

    Abstract: Effective nuclear science communications can inform people about benefits and risks, allowing them to make decisions and choices. Nevertheless, regarding radiological protection, controversies and misinformation distort public's perceptions of radiation risks. This paper offers an overview of ineffective mass media communication and its impacts on citizens' perceptions of nuclear technology. There seem to be a gap between society and the scientific community. The general public do not read high-specialized articles written by scientists. In Knowledge Society, where Internet and social media are the most common source of information, opinion makers seem to privilege sensationalistic rumors about the harmful effects of ionizing radiation, environment contamination and accidents. Moreover, available information about the biological effects of the exposure to ionizing radiation confuse public's perceptions of radiation risks and benefits. Whether experts agree that radiation causes observable health effects at high doses, Intemet highlights controversies on the biological effects of low-dose radiation. Internet reports that the exposure to indoor radon is a risk factor for lung cancer. Intemet 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. This article presents and discusses examples of pseudo-scientific information, newspapers errors, fake news, and anti-nuclear didactic material, where basic concepts are mamipulated, and omission of vital information leads the public to mistrust and fear. Unfounded prejudices, misconceptions and misinformation are delivered in TV news, Intemet articles, social media, TV series, cartoons and even through science journals. The general public, most often, do not have trustful information about radiological protection regulations and recommendations regarding human health, environment protection, management of radioactive waste or safe transport of radioactive material. Finally, this paper emphasizes the importance for scientists to be able to communicate to the public developing science-based communication programs, evaluating the adequacy of those communications, investing in properly scientific divulgation about the risks and benefits of nuclear sciences that impact in citizens' everyday hfe, such as medical applications, industrial applications, public safety and nuclear power generation. The balance between risk perception and risk acceptance depends on effective, trustworthy and understandable mformation. It is essential to educate educators and opinion-makers, combating fake pseudo-scientrfic information, social networks sensationalism and omissions of the media.

    Palavras-Chave: radiation protection; risk assessment; public opinion; information dissemination; public information; nuclear energy; radioactivity

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  • IPEN-DOC 28013

    SOUSA, GRAZIELLY M. de . Estudo experimental sobre a toxicidade do curativo de hidrogel com nanoprata em ratos / Experimental study on the toxicity of hydrogel dressing with nano-silver in rats . 2020. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 75 p. Orientador: José Roberto Rogero. Coorientador: Ademar Benévolo Lugão. DOI: 10.11606/D.85.2020.tde-16062021-151032

    Abstract: OBJETIVOS: avaliar a toxicidade do curativo de hidrogel com nanoprata a 22 ppm e 44 ppm em lesões cutâneas superficiais utilizando ratos Wistar, a partir da análise histopatológica de parte do fígado e rins; avaliar os possíveis efeitos tóxicos sobre as funções renal, hepática e células sanguíneas por meio do hemograma. METODOLOGIA: Trata-se de um estudo pré-clínico. Os curativos de hidrogel e hidrogel com nanoprata com concentrações de 22 e 44 ppm foram produzidos no Centro de Química e Meio Ambiente (CQMA) do IPEN. A pesquisa foi realizada no Biotério da Faculdade Presidente Antônio Carlos em Porto Nacional (FAPAC ITPAC Porto), Tocantins. Foram utilizados 85 ratos, adultos jovens, machos, com idade média de 60 a 90 dias. Os animais foram classificados aleatoriamente em três grupos. O tratamento das lesões foi realizado a cada três dias e uma vez ao dia. Os sinais clínicos e peso corporal dos ratos foram registrados. As amostras sanguíneas e os órgãos foram posteriormente coletados para exame bioquímico. As peças anatômicas, após retirados cirurgicamente, foram submetidas aos procedimentos de rotina para blocagem e histotécnica. O projeto foi aprovado pelo Comitê de Ética no Uso de Animais da FAPAC ITPAC Porto. Todos os dados foram tabulados e analisados pelo software GraphPad Prism version 8.0.1, teste de Shapiro-Wilk para verificar a normalidade dos dados. Para dados não paramétricos utilizou-se o teste de Kruskal-Wallis e as comparações pelo pós-teste de Dunn. Para dados de distribuição normal análise do (ANOVA) e por meio do teste de Tukey. RESULTADOS: Para cada parâmetro hematológico avaliado nos diferentes tempos, os três grupos se comportaram de maneira muito parecida e demonstraram não serem diferentes estatisticamente, salvo poucas exceções ao que se refere as células sanguíneas mononucleares. Na análise de dosagem da uréia as médias do grupo controle comparados com os do demais tratamentos, notou-se que as médias do HP22 foram maiores no tempo de 7 e 14 dias, enquanto que as do grupo do HP44 se apresentaram maiores em 24 horas, 7 dias e 14 dias. Na dosagem de creatinina, somente o grupo (HP44) 14 dias mostrou-se maior. Na comparação das médias de ALT, em relação ao grupo (H), observou-se que as médias do (HP22) foram maiores em 24 h e 3 dias, enquanto que as do grupo (HP44) mostraram ser maiores em 24 h, 7, 14 e 30 dias. No AST notou-se que o (HP22) foi maior em 3, 7 e 14 dias enquanto que o (HP44) foi em 24 h e 7 dias. O estudo não apresentou alterações significativas ao que se refere às análises histopatológicas do fígado e rins. CONCLUSÕES: os curativos de hidrogel com nanoparticulas de prata reticulados e esterilizados por irradiação com raios gama produzidos no IPEN/USP, não induziram toxicidade aos animais e os dados servirão como base para estimar o potencial de risco de eventual exposição à saúde humana.

    Palavras-Chave: rats; rodents; skin; wounds; bioassay; antimicrobial agents; biological models; pvp; irradiation; hydrogels; membranes; toxicity; nanomaterials; silver; distribution; data analysis; kruskal limit

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  • IPEN-DOC 28012

    GROPPO, DANIELA P. . Correlação de parâmetros físicos e dosimétricos de diferentes detectores utilizados em dosimetria de campos pequenos para radioterapia em um acelerador linear clínico / Correlation of physical and dosimetric parameters of different detectors used in small field dosimetry for radiotherapy in a clinical linear accelerator . 2020. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 135 p. Orientador: Linda Viola Ehlin Caldas. DOI: 10.11606/T.85.2020.tde-16062021-145616

    Abstract: Atualmente, as doses administradas em procedimentos radiocirúrgicos são extremamente elevadas, quando comparadas a outros procedimentos radioterápicos. A acurácia dosimétrica para esses tipos de tratamentos requer um comissionamento de campos pequenos de radiação a serem parametrizados em um sistema de planejamento computadorizado. A medição dosimétrica (relativa e direta) de campos pequenos representa um desafio, pois pode introduzir erros na entrega de dose; assim, alguns parâmetros dosimétricos (perfil de dose e porcentagem de dose na profundidade) da interação da radiação com a matéria podem ser comprometidos como o equilíbrio de partículas carregadas. Para melhor mensurar esses dados dosimétricos, alguns detectores são empregados. Mesmo com o uso destes detectores específicos, faz-se necessário identificar e avaliar as incertezas que podem provir do efeito do tamanho do volume e do arranjo experimental do detector sob o campo de radiação. Neste trabalho, as medições dosimétricas foram obtidas com filmes radiocrômicos (medição de referência), câmaras de ionização de volume sensível pequeno, diodos e detectore de diamante. Para correlacionar os parâmetros físicos e dosimétricos obtidos com os detectores, foram utilizados formalismos matemáticos. Esses formalismos matemáticos propostos mostraram-se eficazes quando aplicados à dosimetria de campos pequenos circulares em aceleradores lineares clínicos da fabricante Elekta, modelo Versa HD®, com feixes de fótons (6 MV), com e sem o uso do filtro aplainador (flattening filter).

    Palavras-Chave: linear accelerators; rilac; linac-ring accelerators; quadrupole linacs; radiation detectors; small angle scattering; fractionated irradiation; surgical materials; filters; gamma sources; ionization chambers; dose rates; radiation doses distributions; radiation dose units; measuring methods; phantoms; pmma; computer-aided manufacturing; data covariances; three-dimensional calculations; mathematical solutions; clinical trials; dosimetry; radiotherapy; nuclear medicine

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  • IPEN-DOC 28011

    VILLANI, DANIEL . Desenvolvimento de um simulador antropomórfico de pescoço-tireoide tecido-equivalente impresso em 3D para aplicações multidisciplinares / Development of a 3D printed tissue-equivalent anthropomorphic neck-thyroid phantom for multidisciplinary applications . 2021. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 103 p. Orientador: Letícia Lucente Campos Rodrigues. DOI: 10.11606/T.85.2021.tde-16062021-143936

    Abstract: Objetos simuladores (no inglês, phantoms), dispositivos que representam o corpo humano, têm sido usados nas áreas da física médica, física e engenharia biomédica desde o início. Logo após a descoberta dos raios-X, as notícias dos benefícios médicos da radiação se espalharam rapidamente. A geometria e a composição de um simulador são determinadas pela prática a qual será aplicado. Existem desde os mais simples, baseados em água para medir a saída de feixes de terapia de megavoltagem, aos de maior complexidade, antropomórficos para controle de qualidade em radioterapia. O uso de impressão 3D e filamentos comumente encontrados comercialmente para o desenvolvimento de simuladores está sendo investigado. A aplicação desta técnica para o desenvolvimento de simuladores de baixo custo requer um estudo complexo da interação dos materiais impressos com diferentes tipos e qualidades de radiação, bem como a caracterização de configurações de impressão. Realizando essas medições, é possível encontrar metodologias para que possam simular corretamente o tecido humano. O objetivo desse trabalho constitui no projeto e na construção de um objeto simulador antropomórfico de tireoide (pescoço), utilizando uma impressora 3D e materiais tecido-equivalentes, para ser utilizado em aplicações multidisciplinares. Estudos de equivalência a tecidos humanos para filamentos de PLA, ABS e ABS XCT desenvolvidos no IPEN foram realizados em feixes de fótons padrão. Utilizou-se como base anatômica e de modelagem 3D o simulador comercial ATOM MAX 711, da CIRS. Os dados experimentais mostram a possibilidade de alcançar condições de equilíbrio eletrônico com as mesmas especificações de espessura para PLA e ABS, possibilitando a substituição do PMMA em diversas aplicações dosimétricas. Os filamentos de ABS aditivados com BaSO4 desenvolvidos no IPEN possuem propriedades de atenuação aumentadas significativamente em relação ao ABS puro, PLA e PMMA e são equivalentes aos tecidos ósseos nos feixes estudados. Diferentes tecidos ósseos podem ser simulados com uso de diferentes percentuais de infill. A metodologia de modelagem do simulador 3D deste estudo abre possibilidades de uso de imagens tomográficas de quaisquer objetos, ou até mesmo pacientes, para realização de prototipagem 3D de simuladores cada vez mais específicos e customizados. O simulador desenvolvido apresenta todas as características desejáveis para aplicações em proteção radiológica, dosimetria utilizando detectores TL/OSL, medições de radioisótopos incorporados na tireoide (tanto contadores de contaminação, quanto detectores de medicina nuclear) e treinamento de técnicas de aquisição de imagens por raios-X. Constitui uma alternativa viável de simulador equivalente a tecido; e de baixo custo, se comparado com os simuladores importados.

    Palavras-Chave: endocrine glands; thyroid cells; neck; tissue-equivalent materials; phantoms; pmma; computer-aided manufacturing; filaments; polyacrylates; biomedical radiography; nuclear engineering; x radiation; positron computed tomography; photon emission; radiothermoluminescence; uses; efficiency; performance; differential calculus; three-dimensional calculations

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  • IPEN-DOC 28009

    ZAMBONI, CIBELE B. ; SILVA, DALTON G.N. da ; TASSO, ORION G. ; MEDEIROS, JOSE A.G. de ; AZEVEDO, MARIA R.A. de. Quantitative analysis of light elements using compact XRF spectrometers. In: SALES, FRANCISCO O. (Org.). Ciências exatas e da terra: exploração e qualificação de diferentes tecnologias 4. Ponta Grossa, PR: Atena Editora, 2021. p. 178-186, cap. 16. DOI: 10.22533/at.ed.13021130116

    Abstract: The performance of two compact X-Ray Fluorescence (FRX) spectrometers consisting of Ag and Au X-ray mini-tubes associated with a Si Drift detector was checked for clinical finality. Using the Energy Dispersive X-Ray Fluorescence technique (FRXDE) specific light elements of clinical relevance (Ca, Cl, K and Fe) were determined in human whole blood samples without chemical digestion using direct and non-destructive analysis, in air atmosphere. A comparative study between Ag and Au targets data was carried out and the results are in good agreement.

    Palavras-Chave: x-ray fluorescence analysis; blood; quantitative chemical analysis; clinical trials; diagnostic uses

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  • IPEN-DOC 28008

    SILVA, DALTON G.N. da ; ZAMBONI, CIBELE B. ; ALMEIDA, MATEUS R. de ; MEDEIROS, JOSE A.G. de . Análise de zinco em sangue de corredores de longa distancia. In: SOUZA, LUCIO M.V. (Org.). Educação física e ciências do esporte: pesquisa e aplicação de seus resultados 2. Ponta Grossa, PR: Atena Editora, 2021. p. 227-234, cap. 19. DOI: 10.22533/at.ed.30721220119

    Abstract: O objetivo deste estudo foi avaliar o zinco no sangue de atletas por metodologia de ativação de nêutrons. Os resultados mostraram deficiência de zinco para a maioria dos atletas. O estudo mostrou a eficácia da utilização desse procedimento analítico para sucessivas avaliações clínicas, durante o período de preparação das competições, fornecendo dados que auxiliam na elaboração de uma dieta balanceada, bem como contribuem para a proposição de novos protocolos de avaliação clínica.

    Palavras-Chave: biochemistry; exercise; biological fatigue; physiology; zinc; blood circulation; neutron activation analysis

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  • IPEN-DOC 28007

    GONZAGA, ANDERSON do B.; SILVA, EDUARDO P. da; TERAM, ROGERIO; NASCIMENTO, MAURICIO S.; SANTOS, VINICIUS T. dos; SILVA, MARCIO R. da; COUTO, ANTONIO A. ; SANTOS, GIVANILDO A. dos. Análise de ligas de cobre e a influência da inserção de nióbio: uma revisão. In: HOLZMANN, HENRIQUE A. (Org.). Impactos das tecnologias na engenharia de materiais e metalúrgica 2. Ponta Grossa, PR: Atena Editora, 2021. p. 19-26, cap. 3. DOI: 10.22533/at.ed.3142119013

    Abstract: O presente trabalho tem como finalidade desenvolver uma revisão bibliográfica sobre a influência de processos de fabricação que envolvem cobre com a inserção de nióbio na microestrutura e propriedades resultantes. Foram utilizadas literaturas específicas na busca por material bibliográfico para esta revisão como: artigos, capítulos de livros, Springerlink, Google Scholar, trabalhos de conclusão de curso e livros. Foram obtidas as seguintes conclusões: (1) o nióbio pode ser utilizado como refinador de grão do cobre; e (2) a porcentagem de nióbio adicionada a liga de cobre deve ser mínima, pois altas quantidades produzem um material poroso e de qualidades mecânicas baixas, no caso da metalurgia do pó.

    Palavras-Chave: metallurgy; microstructure; copper alloys; niobium; manufacturing; mechanical properties

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  • IPEN-DOC 28006

    GOMES, MAURILIO P. ; REIS, LUIS A.M. dos; BETINI, EVANDRO G.. Simulação computacional de recristalização de grãos. In: . Engenharia no Século XXI. Belo Horizonte, MG: Poisson, 2020. p. 100-105, v. 16, cap. 12. DOI: 10.36229/978-65-86127-70-6.CAP.12

    Abstract: Um modelo de Monte Carlo bidimensional foi desenvolvido para simular a recristalização de grãos na presença de uma partícula circular imóvel para diferentes valores de energias armazenadas. Para energias armazenadas maiores que um valor crítico (H/J = 2,01) a propagação da recristalização pôde facilmente transpor a partícula imóvel, levando a uma densidade aleatória dos grãos e a uma influência insignificante da partícula imóvel na cinética da recristalização. Para energias armazenadas mais baixas (H/J = 0,1), a partícula imóvel limita a propagação da recristalização, levando à uma recristalização incompleta.

    Palavras-Chave: computerized simulation; monte carlo method; recrystallization; grain growth

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  • IPEN-DOC 28005

    LEBRAO, GUILHERME W.; JERMOLOVICIUS, LUIZ A.; MORAES, VIVIANE T. de; LEBRAO, SUSANA M.G.; ROSSI, JESUALDO L. . Compósito reforçado com fibra de carbono e nanotubos funcionalizados com auxílio de microondas. In: BARBOSA, FREDERICO C. (Ed.). Engenharia Química: princípios fundamentais. Piracanjuba, GO: Editora Conhecimento Livre, 2020. p. 106-112, v. 1, cap. 10. DOI: 10.37423/200802332

    Abstract: O objetivo deste trabalho foi o desenvolvimento de um material compósito reforçado com fibra de carbono e nanotubos funcionalizados, onde se realizou a caracterização térmica e a resistência mecânica do produto final. Desenvolveu-se neste trabalho um procedimento para incorporação de nanotubos de carbono (NTC) em uma resina fenol / epóxi a ser utilizado como matriz de um compósito de fibra de carbono. Realizando para tal, a oxidação dos NTC com o uso de micro-ondas e sua funcionalização com 3-amino-propil-tri-etoxi-silano, usado como agente de acoplamento entre a resina e o NTC. Após o processamento, como resultado da adição dos NTC na resina, obteve-se um aumento na sua temperatura de transição vítrea. No material compósito fibra de carbono, obtido por laminação manual, onde a resina fenol / epóxi mais NTC foi usada como matriz, obteve-se o aumento do limite de resistência à tração e ao impacto, confirmado por uma análise de variância com 95% de confiança, mostrando a eficácia no tratamento dos NTC.

    Palavras-Chave: composite materials; carbon fibers; nanotubes; microwave radiation

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  • IPEN-DOC 28001

    CAYRES, ROSANA M.V.; RUIZ, MAURO S.; AQUINO, SIMONE . Educação ambiental para a melhoria contínua do plano de logística sustentável da Companhia Nacional de Abastecimento Superintendência Regional de São Paulo. In: PACHECO, JULIANA T.R. (Org.); KAWANISHI, JULIANA Y. (Org.); NASCIMENTO, RAFAELLY do (Org.). Meio ambiente e desenvolvimento sustentável 2. Ponta Grossa, PR: Atena Editora, 2019. p. 134-148, v. 2, cap. 13. DOI: 10.22533/at.ed.55019111113

    Abstract: Várias são as iniciativas que tentam responder aos desafios da sustentabilidade e uma delas é a educação ambiental (EA). O estudo apresentou como objetivo geral propor ações de EA para contribuir com a melhoria contínua dos resultados do plano de logística sustentável (PLS) da Companhia Nacional de Abastecimento e como objetivos específicos, conhecer as opiniões dos funcionários em relação ao PLS e às atividades realizadas durante a sua execução no primeiro ciclo, analisar os relatórios de consumo de serviços e bens relacionados no PLS, além de identificar as lições aprendidas pelos integrantes da comissão gestora do PLS ao longo do período de implantação. Foi uma pesquisa aplicada, com abordagem mista. Quanto aos objetivos, tratou-se de uma pesquisa de avaliação. As etapas metodológicas foram: pesquisa documental, aplicação de survey aos funcionários e realização de grupo focal, para se chegar ao tratamento e análise dos dados. Apesar de nem todas as metas do PLS terem sido alcançadas, observou-se resultados favoráveis em todos os aspectos analisados, com aprovação dos funcionários às atividades desenvolvidas, chegando-se a sistematização de dez lições aprendidas. Ao final, foram apresentadas 21 ações de EA que podem ser incorporadas ao novo ciclo do PLS, visando à melhoria contínua do mesmo. O estudo mostrou-se relevante e de ampla contribuição às instituições da administração pública que pretendem dar os primeiros passos no sentido de implantar suas ações de educação ambiental, bem como àqueles que vem enfrentando desafios ao selecionar as melhores práticas de sustentabilidade e alcançar os resultados propostos em seus PLS.

    Palavras-Chave: sustainable development; sustainability; education; training; environmental protection; resource conservation

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  • IPEN-DOC 28000

    PEREIRA, MARCO A.S. . Ciência: o prazer de descobrir. São Paulo, SP: Sagitarius Editora, 2020. 259 p.

    Palavras-Chave: scientific personnel; research programs; historical aspects; technology impacts; social impact; investment; education

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  • IPEN-DOC 27999

    AGUIAR, ANDRE S. de ; LEE, SEUNG M. ; SABUNDJIAN, GAIANE . Calculation of the dose for public individuals due to a severe accident at the Angra 2 nuclear plant, Brazil. In: AWWAD, NASSER (Ed.). Nuclear power plants: the processes from the cradle to the grave. London, UK: IntechOpen, 2021. p. 1-16, cap. 6. DOI: 10.5772/intechopen.92200

    Abstract: Through a severe accident at nuclear power plant Angra 2, the whole body dose effective of the individuals members of the public located in the Emergency Planning Zones (EPZs) will be calculated, and later, the protective actions in these EPZs will be analyzed. Two different scenarios of radionuclide release into the atmosphere will be considered. In the first scenario, 2 h of the release of Xe, Cs, Ba, and Te, and the second scenario, 168 h of release.

    Palavras-Chave: nuclear power plants; severe accidents; radiation doses; sbloca; atmospherics; dispersions

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  • IPEN-DOC 27998

    FREITAS, LUCAS F. de . Nanomaterials for enhanced photodynamic therapy. In: INADA, NATALIA M. (Ed.). Photodynamic therapy: from basic science to clinical research. London, UK: IntechOpen, 2021. p. 1-16, cap. 12. DOI: 10.5772/intechopen.94255

    Abstract: Photodynamic therapy is a non-invasive option for eliminating superficial tumors and to control infections. However, despite some protocols are already approved for the clinic, PDT applications could be much broader if some of its main hindrances were overcome. For instance, the most efficient photosensitizers are hydrophobic, so if one injects them intravenously they tend to aggregate and to be internalized by phagocytes in the blood, impairing the delivery to the target site. In addition, visible light has a limited penetration in tissues, therefore the main applications of PDT are limited to superficial tumors unless an invasive procedure is used for the light to reach deeper sites. Another setback is the hypoxia that commonly happens in tumors, hindering the full potential of PDT as it depends on a constant oxygen supply. In this chapter the reader will find some strategies based on Nanotechnology to overcome these and other obstacles for PDT to reach its full clinical potential, i.e. hypoxia-reverting protocols, X-ray-driven PDT, Cherenkov radiation-driven PDT, and active tumor-targeting.

    Palavras-Chave: photodynamic therapy; nanotechnology; photons; x radiation; photosensitivity

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  • IPEN-DOC 27997

    BITTENCOURT, SONIA R.M. de; BUSCH, SUSANNA E. ; CRUZ, MARCIO R. da. The Clean Development Mechanism in Brazil. In: FRANGETTO, FLAVIA W. (Ed.); VEIGA, ANA P.B. (Ed.); LUEDEMANN, GUSTAVO (Ed.). Legacy of the CDM: lessons learned and impacts from the Clean Development Mechanism in Brazil as insights for new mechanism. Brasília, DF: IPEA, 2019. p. 43-58, cap. 2.

    Palavras-Chave: pollution regulations; environmental policy; kyoto protocol; greenhouse effect; greenhouse gases

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  • IPEN-DOC 27996

    LIMA, CASSIO ; CORREA, LUCIANA; BYRNE, HUGH; ZEZELL, DENISE M. . Influence of the reference spectrum used as input to the RMieS-EMSC algorithm for correction of spectral distortions induced by Mie scattering in FTIR hyperspectral images. In: SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, October 7-9, 2019, São Paulo, SP. Abstract... Piscataway, NJ, USA: IEEE, 2019. p. 47-48.

    Abstract: Fourier transform infrared (FTIR) microspectroscopy has shown great promise as a tool to assess the histological architecture of tissue samples by providing morphochemical maps that enable the evaluation of both spatial and compositional information based on the signatures of molecular vibrations. However, FTIR datasets collected in transmission and transflection modes are subjected to undesired spectral contributions non-related to the phenomenon of light absorption that must be corrected prior any analysis. The algorithm so-called “Resonant Mie Scattering – Extended Multiplicative Scatter Correction (RMieS-EMSC)” has been well succeeded in vibrational spectroscopy in removing spectral distortions. The main idea of the algorithm is to reconstruct the datasets that present undesired spectral contributions based on a scatter-free reference spectrum. In this study, FTIR hyperspectral images acquired from cutaneous malignant lesions were submitted to RMieS-EMSC protocol using Matrigel and average spectrum in order to evaluate the influence of the reference spectrum in the final correction. False-color maps obtained after segmentation were compared in terms of image quality and consistency with standard histopathology in order to evaluate the ability of each method to reproduce the histological structures of the specimen. Our findings indicate that the choice of reference spectrum has very little difference on the outcome of image analysis. The images obtained by both spectra used as reference may not have resulted in identical false-color maps, but the differences between the morphochemical maps are relatively small.

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  • IPEN-DOC 27995

    MACHADO, NEILA; SATO, ERIKA; BORTOLETTO, DAIANA; LIMA, CASSIO ; ZEZELL, DENISE M. ; MARTINHO, HERCULANO. Computational models for light-tissue interactions: recent advances. In: SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, October 7-9, 2019, São Paulo, SP. Abstract... Piscataway, NJ, USA: IEEE, 2019. p. 26-26.

    Abstract: Computational simulations could be used as a tool to better understand how biochemical changes translate into structural changes that generate pathological states. By computational calculations, it is possible to obtain the vibrational spectrum of molecules and macromolecules. It is possible to verify which atoms or molecules contribute to the existence of each characteristic vibrational mode, identify and interpret the interactions between these modes, and associate these pieces of information to the pathological processes. In this work we will present recent advances from our group by using density functional theory (DFT) to model normal, inflammatory, and tumoral tissues in a minimalist way (100 atoms). Comparison with experimental data (vibrational spectroscopy data) will also be presented. Perspectives on using molecular dynamics on large models (> 60,000 atoms) will also be discussed.

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  • IPEN-DOC 27994

    CASTRO, PEDRO ; LIMA, CASSIO ; ZORN, TELMA; ZEZELL, DENISE M. . Assessment of burn wounds status using mid-infrared spectroscopy. In: SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, October 7-9, 2019, São Paulo, SP. Abstract... Piscataway, NJ, USA: IEEE, 2019. p. 20-21.

    Abstract: Burns are one of the major causes of morbidity and the most costly traumatic injuries worldwide. Better understanding of the molecular mechanisms associated with wound healing might provide improved clinical strategies to speed up the tissue repair process and reduce the global impact of burns on public health services. The traditional techniques used to assess the biochemical events related to wound repair are laborious, time-consuming and require multiple staining. Thus, the present study aims to evaluate the feasibility of Fourier transform infrared (FTIR) spectroscopy in order to monitor the progress and healing status of burn wounds. Third-degree burn injuries were induced on Wistar rats by water vapor exposure. Afterwards, biopsies specimen was extracted for further histopathological examination and spectroscopic evaluation at 4 time-points (3, 7, 14 and 21 days). Raw spectral data were offset-corrected and normalized by amide I band area. The second derivatives were compared by the Principal Component Analysis (PCA). On days 3 and 7, when compared to healthy group, biomolecules bands were most prominent. However, on days 14 and 21, these molecular bands decreased. Therefore, our pairwise comparison revealed that metabolic activity induced by thermal injury decreases as the healing process progresses. Our findings show that FTIR spectroscopy can monitor the biochemical development induced by burn injury and detect the status of wound repair.

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  • IPEN-DOC 27993

    ZANINI, NATHALIA ; ZAMATARO, CLAUDIA B. ; RABELO, THAIS F. ; JUVINO, AMANDA C. ; KUCHAR, NIELSEN G. ; CASTRO, PEDRO ; ANA, PATRICIA da; ZEZELL, DENISE . Analysis of ceramic laminates removal with Er,Cr:YSGG laser by optical coherence tomography. Photobiomodulation, Photomedicine, and Laser Surgery, v. 37, n. 10, p. A22-A22, 2019. DOI: 10.1089/photob.2019.29013.abstracts

    Abstract: Porcelain laminated veneers have been widely used. For wear of hard tissue such as enamel and dentin, the diamond rotary instrument is the most traditional, but the laser has become recently used to remove aesthetic facets. Optical coherence tomography (OCT) used as an optical biopsy, is important for morphological analysis and attenuation coefficient is related to the property of the photons to be scattered by the samples. After approval by the Ethics Committee, the present study investigated the detachment of 30 ceramic E-max fragments cemented in human dental enamel of dimensions 3mm x 3mm x 0.7mm with 3 types of resin cements, RelxY Veneer, Relx U200 and Variolink Veneer. The samples (Enamel + Ceramic Fragment) were randomly distributed in the 3 groups and cemented according to the manufacturer. After that, they were prepared for irradiation with the Er,Cr: YSSG laser under predetermined conditions (3.5 and 3W, 20Hz, 60% water and 40% air flow). OCT analysis was done before and after irradiation. We observed that themorphological changes of the enamel surface showed an increased surface area due to the cement remaining in the enamel.We concluded that the Er, Cr: YSGG laser, when used in the irradiation protocol tested, seems to be a safe tool for the removal of laminates.

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  • IPEN-DOC 27992

    RABELO, THAIS F. ; ZAMATARO, CLAUDIA B. ; ZANINI, NATHALIA ; JUVINO, AMANDA C. ; KUCHAR, NIELSEN G. ; CASTRO, PEDRO A.A. ; ZEZELL, DENISE M. . Removal of laminates with Er,Cr:YSGG laser from dental enamel submitted to gamma radiation. Photobiomodulation, Photomedicine, and Laser Surgery, v. 37, n. 10, p. A21-A21, 2019. DOI: 10.1089/photob.2019.29013.abstracts

    Abstract: Background: Modern Dentistry is characterized by the search for aesthetic perfection in the smile. Many efforts are made regarding procedures related to manufacturing, cementing, maintenance and removal of ceramic laminates. The laser removal of laminates has become more frequent when the aesthetical procedures needs to be replaced. On the other hand, the head and neck cancer treatment causes comorbidities in the buccal environment when laminates are in place. Objective: To evaluate in vitro the removal of ceramic fragments by means of Er,Cr:YSGG laser irradiation, after gamma radiation. Methods: 20 Lithium disilicate veneers were cemented with Variolink to human dental enamel and then samples were irradiated with 0.07 kGy. After gamma irradiation, the laminates removal with Er,Cr:YSGG laser was performed. The control group was not subjected to gamma radiation. Dental enamel samples were analyzed by Scanning Electron Microscopy (SEM), Fourier Transformed Infrared Spectroscopy (FTIR) and Surface Microhardness Loss (SMH). Results: SEM has shown that less cement was found after removal of the facets in gamma irradiated group when compared to the control. For both groups there was alteration of the SMH possibly due to the use of the adhesive system. When performed intra group analysis, the sample being its own control of baseline in the FTIR analysis, there were no band shifts or formation of new compounds on the surface of human dental enamel. Conclusions: The Er,Cr:YSGG laser is an effective alternative for laminates removal in human dental enamel even when it is subjected to gamma radiation.

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  • IPEN-DOC 27991

    KUCHAR, NIELSEN G. ; ZAMATARO, CLAUDIA B. ; RABELO, THAIS ; JUVINO, AMANDA ; ZANINI, NATHALIA ; CASTRO, PEDRO ; ZEZELL, DENISE M. . Calcium analysis of gamma sterilized human dentin submmited to Er,Cr:YSGG laser irradiation. Photobiomodulation, Photomedicine, and Laser Surgery, v. 37, n. 10, p. A18-A19, 2019. DOI: 10.1089/photob.2019.29013.abstracts

    Abstract: Studies report that gamma radiation changes the oral cavity of patients submitted to radiotherapy. These changes include xerostomia, resulting in an unsaturation of calciumand phosphate in the oral cavity. However, human enamel samples isolated from the altered oral environmentwhen irradiatedwithgamma radiation at doses of up to 25kGy (much higher than radiotherapy doses) were shown to have undergone no changes in molecular hardness or micro surface. After approval of the Research Ethics Committee, 20 human dentin samples were evaluated before and after irradiation, split randomly into control group (n = 10) and irradiated group (n = 10) treated with 25.0 kGy at the Co60 multipurpose irradiator and irradiated with Er,Cr:YSGG laser in the parameters: 8.5 J/cm2 in the Fourier Transform Infrared Spectroscopy (FTIR), % surface Microhardness loss and Scanning Electron Microscopy (SEM). At the end, acidic biopsies were performed to quantify the concentration of calcium present in the samples. In the results of FTIR analysis differences were found only in the bands of organic content and in the inorganic content, difference were not found between before and after irradiations. The EDS and % Surface Microhardness loss analysis corroborates these findings, as well as no significant loss of the Calcium content before and after their radiation with Co60 at 25 kGy and with the Er,Cr:YSGG laser. These findings lead us to a new hypothesis of behavior of the hydroxyapatite crystal submitted to the gamma irradiation.

    Palavras-Chave: teeth; radiotherapy; gamma radiation; radiation doses; calcium

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  • IPEN-DOC 27990

    ZAMATARO, CLAUDIA B. ; RABELO, THAIS F. ; ZANINI, NATHALIA ; JUVINO, AMANDA C. ; KUCHAR, NIELSEN G. ; CASTRO, PEDRO A.L. ; ANA, PATRICIA A. da; ZEZELL, DENISE M. . Er,Cr:YSGG laser irradiation associated to fluoride for in situ model using gamma sterilized dentin and enamel. Photobiomodulation, Photomedicine, and Laser Surgery, v. 37, n. 10, p. A13-A13, 2019. DOI: 10.1089/photob.2019.29013.abstracts

    Abstract: The in situ intraoral model uses human dental enamel samples (HDE) in order to analyse the de-remineralization processes using the buccal environment without interfering into the patients’ natural dentition. The main ethical concern from this model is the biosafety. Gamma radiation is a very efficient sterilization method that is not expected to alter the mineral content of the hard tissues, avoiding biases in the results. Thus 40 HDE samples were irradiated through a source of 60Co multipurpose irradiator aiming complete sterilization (25 KGy/h) with the purpose of accumulating the native plaque on them at an in situ study. An Er,Cr:YSGG laser was used alone and in combination with the topical applications of: 1-dentifrice (1,100 lg F-/g) or 2-APF (12,300 lg F-/g). Morphological analyses were performed by scanning electron microscopy (SEM), determination of alkali-soluble fluoride concentration by specific ion electrode and microhardness determination. Then, the 15 volunteers used palatal devices containing previously treated HDE samples and remained using F dentifrice. The FTIR findings established that gamma radiation could be used aiming HDE sterilization. The Knoop hardness number was within the range of that of natural dentin of human origin. X-ray fluorescence shows that irradiated dentin has great similarity with natural dentin from the point of view of chemical composition. SEM analyses showed that there was no thermal damage or interprismatic morphological changes in the hydroxyapatite structure of human dental dentin outside the buccal environment when using doses of gamma irradiation up to 25 kGy.

    Palavras-Chave: teeth; enamels; sterilization; lasers; irradiation

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  • IPEN-DOC 27989

    JUVINO, AMANDA C. ; ZAMATARO, CLAUDIA B. ; RABELO, THAIS F. ; KUCHAR, NIELSEN G. ; ZANINI, NATHALIA ; CASTRO, PEDRO ; ZEZELL, DENISE . In vitro determination of the critical pH demineralization of human dental enamel irradiated with Nd:YAG laser associated with fluoridated product. Photobiomodulation, Photomedicine, and Laser Surgery, v. 37, n. 10, p. A8-A9, 2019. DOI: 10.1089/photob.2019.29013.abstracts

    Abstract: The use of fluoride products associated with high intensity laser irradiation are beneficial for dental caries prevention because it increases the surface area, improving the formation of fluorapatite (FA), which gives greater acid-resistance of enamel against bacterial acids. The objective of this study is to determine the critical pH of dental enamel treated with acid fluoride phosphate 12,300 lF-/g (APF) and Nd:YAG laser 84 J/cm2, as there is no precedent to determine this pH. The study consisted of 4 groups (n = 15): G1: Negative Control; G2: APF; G3: Nd:YAG; G4: APF + Nd:YAG. Each group was randomized into three subgroups (n = 5) for pH cycling. The cycling was designed to simulate three conditions: below critical pH of enamel hydroxyapatite (pH 5.0); pH below critical for hydroxyapatite and fluorapatite (pH 4.5); condition further below the critical situation to investigate extent of acid resistance of the enamel (pH 4.0). The samples were analyzed by scanning electron microscopy (SEM), Fourier infrared spectroscopy (FTIR) and solutions were quantified fluoride (specific ion electrode) and phosphate (colorimetric method). In SEM and FTIR (phosphate band) at pH 5, only the APF and APF + Nd:YAG groups did not present demineralization. At pH 4.5, only the APF + Nd:YAG group was integrated. At pH 4, APF + Nd:YAG showed signs of mild demineralization while the other groups showed aggressive signals. It is concluded that the irradiated fluorapatite has critical dissolution pH different from fluorapatite formed only with the application of fluorine.

    Palavras-Chave: teeth; enamels; fluorides; phosphates; ph value; laser radiation

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  • IPEN-DOC 27988

    CACHEFFO, A.; LOPES, F.J.S. ; YOSHIDA, A.C.; LANDULFO, E. . Classifying aerosols with machine learning techniques using the AERONET and CALIPSO satellite databases. In: SP SCHOOL OF ADVANCED SCIENCE ON ATMOSPHERIC AEROSOLS, July 22 - August 2, 2019, São Paulo, SP. Abstract... São Paulo, SP: Instituto de Física - USP, 2019. p. 102-102.

    Abstract: In this work, our intention is to develop ways to correlate and classify several types of aerosols, by practical and objective manners, with the aim of machine learning techniques (specially decision trees and random forests) [1, 2]. For this purpose, we are intended to use the AERONET (Aerosol Robotic Network) and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) satellite databases [3]. The AERONET database, which includes measurements made since year 2000, will provide to us a reference standard for the categorization and classification of aerosols present in atmosphere [3]. Following this, the databases for the measurements made by the CALIPSO satellite will be addressed, also with the objective of categorizing and classifying aerosols. Such data mining processes will enable us to carry out statistical and climatological analyzes of these databases, allowing a better study of the atmospheric behavior of aerosols in the Earth’s atmosphere [4]. We believe that the development of such tools and techniques for treatment of data provided by AERONET and CALIPSO will contribute greatly to a better understanding of climate change processes on Earth, a subject of scientific interest, especially in recent years.

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  • IPEN-DOC 27987

    OLIVEIRA, D.C.; HOELZEMANN, J.J.; LANDULFO, E. ; ARBOLEDAS, L.A.. Aerosol optical properties in the atmosphere of Natal/Brazil measured a sun photometer of the AERONET. In: SP SCHOOL OF ADVANCED SCIENCE ON ATMOSPHERIC AEROSOLS, July 22 - August 2, 2019, São Paulo, SP. Abstract... São Paulo, SP: Instituto de Física - USP, 2019. p. 95-95.

    Abstract: The study of atmospheric aerosols contributes to the understanding of radiative forcing and global warming. In addition, aerosols may influence visibility, acid rain, human health and precipitation. Since 2016, Natal, capital of Rio Grande do Norte, Brazil, has a solar photometer (CIMEL) of the RIMA-AERONET network that can identify the presence of biomass burning aerosols and desert dust from Africa. For this identification, it is aimed to characterize the optical properties of these aerosols present in the atmosphere of Natal (RN). The data available by AERONET, at level 1.5, Version 3, provide information on some microphysical characteristics such as Optical Aerosol Depth (AOD), Ångström coefficient ( ), Single Scattering Albedo (SSA), Asymmetry Factor (g), Complex Refractive Index (N), Volume Size Distribution (VSD) and Precipitable Water. The data collection period was from August 2017 to August 2018. Aerosols were classified based on global climatologies and their optical properties were described. Observations were compared with daily measurements from satellites and the local LIDAR over the course of a day for a case study. In addition, backward trajectories were modeled with the HYSPLIT model to verify the predominant origin of the air masses. Aerosols present in the atmospheric column of Natal showed monthly means of AOD in the range of 0.10 to 0.15 with peak of 40%, monthly means of between 0.6 and 0.8 with peak above 30%, bimodal DTV with dominant coarse mode, SSA about 0.8, real part around 1.5, imaginary part raging from 0.0125 to 0.0437 and g above 0.74. The Precipitable Water accompanied the increase of the precipitation for the months of December, January, February and March. The classification identified mixed aerosols (60.40%), marine aerosols (30.69%) and mineral dust (8.91%). The backward trajectories showed that in 51% of the cases the continental aerosols origined from the Africa.

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  • IPEN-DOC 27986

    CORREA, T. . Determination of CH4 in mangrove area using LIDAR Raman and Cavity Ringdown Laser Spectroscopy. In: SP SCHOOL OF ADVANCED SCIENCE ON ATMOSPHERIC AEROSOLS, July 22 - August 2, 2019, São Paulo, SP. Abstract... São Paulo, SP: Instituto de Física - USP, 2019. p. 79-79.

    Abstract: Natural wetlands are considered important sources of atmospheric methane, and several researchers have attempted to quantify global emissions from wetland environments. Therefore, this project was conducted an experimental data sample in Itanhaém region, which explored the spatial variability of methane flow within a system with no anthropogenic wetland impact known as mangrove. The study area is located in the coastal region of São Paulo state, region of Atlantic Forest preservation, with large mangrove area. Since remote sensing is a method non-invasive, we were able to detect the emission of methane in areas that do not undergo human intervention, estimating the release of natural gas. The Lidar Raman method reduce the complexity system and cost of mobile and real-time analytics. The system used includes a commercial laser pulsed Nd:YAG Quantel S.A., model CFR 200, with wavelengths of 355 nm, 353 nm and 396 nm, 120 mJ pulse power, with laser repetition rate of 20 Hz and pulse width of 20 s, with a spatial resolution of 7.5 m. The system includes an ethernet interface, used together with LabView software to control the measurement and readout of the acquired data. For an exchange and precision data the Cavity Ringdown Laser Spectroscopy (CRDS) was used functioned with light absorbing at specific wavelengths and its ability to detect mole fractions in ppt (part per trillion) detecting small amounts of gases. Advances in CRDS in cavity-enhanced absorption spectroscopy techniques provide dramatic increases in optical path length and, as a result, allow ultra-sensitive trace gas measurements using robust, reliable and near-infrared temperature room-temperature diode lasers. The results indicated that the spatial variability of the flow within a wetland ecosystem can introduce significant results when compared to areas with impacts with fugitive gases, as well as in extrapolations to larger areas, even if the extension of the ecosystem is well known.

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  • IPEN-DOC 27985

    ANDRADE, I. da S. ; LANDULFO, E. ; ARAUJO, E.C. ; MENDONCA, F. de M. ; SALANI, M.H.G. de A. ; CORREA, T. ; MARQUES, M.T. ; COSTA, R.F. da; GUARDANI, R.. Analysis of the dispersion of aerosol in Cubatão-SP using remote sensing techniques. In: SP SCHOOL OF ADVANCED SCIENCE ON ATMOSPHERIC AEROSOLS, July 22 - August 2, 2019, São Paulo, SP. Abstract... São Paulo, SP: Instituto de Física - USP, 2019. p. 78-78.

    Abstract: Aerosls are emitted by a several sources, these can be antropogenic – emitted by human activities - or natural.Their sudies are an important, because its impacts on the dynamics of the Earth’s atmosphere are huge. The study area have one of the most important industrial complex in the state of Sao Paulo. In the past the city of Cubatão was known as “death valey”, due to the environmental problems caused by the high levels of pollutants that was emitted by the industries. Following this event, regulatory laws on atmospheric emissions were developed, both at the state and federal levels. Today, although Cubatão has lower levels of pollution and controlled industrial emissions, but it is possible to observe overcoming air quality standards. Based on the presented context, the present work aims to conduct a study of the dispersion of aerosols in the region of Cubatão-SP using several techniques, such as: remote sensing (elastic lidar and wind lidar), satellite data, air quality information and also simulations of air masses using a model.

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  • IPEN-DOC 27984

    MACEDO, F. . Correlation between two different real time data acquisition systems: LIDAR Raman and Cavity Ringdown Laser Spectroscopy, for CH4 as a fugitive gas, in São Paulo Metropolitan Area. In: SP SCHOOL OF ADVANCED SCIENCE ON ATMOSPHERIC AEROSOLS, July 22 - August 2, 2019, São Paulo, SP. Abstract... São Paulo, SP: Instituto de Física - USP, 2019. p. 77-77.

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

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  • IPEN-DOC 27983

    BEU, C. . Atmospheric dispersion comparative study between a typical and a disturbed PBL using a doppler lidar. In: SP SCHOOL OF ADVANCED SCIENCE ON ATMOSPHERIC AEROSOLS, July 22 - August 2, 2019, São Paulo, SP. Abstract... São Paulo, SP: Instituto de Física - USP, 2019. p. 73-73.

    Abstract: An atmospheric dispersion study was conducted for 2 different synoptical conditions for a hypotetical nuclear accident: the first is a pre-frontal condition with a typical Planetary Boundary Layer (PBL) and the second is a disturbed PBL due to a synoptic though. The site is a complex terrain area (Ipero - Brazil), where the topography modulates the circulation and the Low Level Jet (LLJ) is a common feature of the PBL. For one year a doppler lidar retrieved the wind vertical profile at Ipero, allowing to evaluate datasets that can be used as input data for the Atmospheric Transport and Dispersion Models (ATDM). Of the 3 datasets evaluated, only GDAS reproduced the LLJ and was chosen for running the HYSPLIT4 ATDM experiments.

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  • IPEN-DOC 27982

    NASCIMENTO, CARLOS E. ; SALES, TATIANE da S.N. ; CARBONARI, ARTUR W. . Investigation of HfO2 and ZrO2, separately and also in the form of mixtures, pure and doped with Si. In: INTERNATIONAL CONFERENCE ON HYPERFINE INTERACTIONS AND THEIR APPLICATIONS, February 10-15, 2019, Goa, India. Abstract... Mumbai, India: Tata Institute of Fundamental Research, 2019. p. 85-85.

    Abstract: The HfO2 has been used in several technological applications, one of which is the replacement of silicon oxide as the material for the door in the manufacture of CMOS-FET devices [1]. ZrO2 also has several applications, being more used in the form of solid electrolytes and oxygen sensors and also in electrochemical pumps. Due to the similarity of the size and properties, that is found in the proportion of 1 to 2 % in the ore of this one. Since the ions of these elements are nearly identical in size, the separation is difficult, and is in most cases unnecessary due to the similarity of its properties [2]. Doping with other elements improves the specific characteristics of HfO2 and ZrO2, making them useful for different applications and extending their uses in CMOS-FET devices. It also reduces the ZrO2 defects, such as its low resistance to high temperatures, causing in the formation of polycrystalline films and decreasing the dielectric constant that can occur due to leakage current in the grain boundaries, making it necessary to use an amorphous interface to reduce losses. In addition, grain size and orientation change throughout a polycrystalline film, which can cause variations in the value of producing irreproducible properties [3]. In this project the atomic scale investigation of HfO2 and ZrO2 was carried out separately and also in the form of pure, doped mixtures with Si [4]. They were used (RBS), X-ray Diffraction [5] and SEM for caracterization. The PAC technique was used to measure the hyperfine parameters, such as the electric field gradient (Vzz), the asymmetric parameter of the electric field gradient (η) and the possible magnetic hyperfine field over a wide temperature range (from 10 to 1300 K). The measurements were performed in order to correlate the results with the behavior of the characteristic properties of each compound to understand the microscopic mechanisms that give rise to these phenomena [6].

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  • IPEN-DOC 27981

    LEITE NETO, O.F.S. ; SANTOS, B.S. ; NARESSI, A.L.E. ; SALES, T.S.N. ; SAXENA, R.N. ; CARBONARI, A.W. . Study of hyperfine interactions in Perovskite structure CaTiO3 with perturbed angular correlation spectroscopy. In: INTERNATIONAL CONFERENCE ON HYPERFINE INTERACTIONS AND THEIR APPLICATIONS, February 10-15, 2019, Goa, India. Abstract... Mumbai, India: Tata Institute of Fundamental Research, 2019. p. 84-84.

    Abstract: Ceramic materials of the perovkista were identified as candidates for immobilization of medium and high levels of radioactive waste due to the fact that they are thermodynamically chemically and physically stable. Because it is a nuclear technique, PAC spectroscopy has great precision and efficiency in the measurement of local hyperfine fields on an atomic scale, constituting an ideal tool for the investigation of the atomic origin of structural phenomena, such as the influence of defects in the macroscopic properties of many materials or the local neighborhood of metallic atoms in the oxide structure. The samples has been prepared by sol-gel method and characterized by X-ray diffraction. In this study the time differential perturbed angular correlation (PAC) spectroscopy was used to study the structure of CaTiO3 and the possible defects made by radiation exposure. The probe nucleus used in this research was 111Cd. The PAC method is based on the hyperfine interaction of nuclear moments of the probe with extra nuclear magnetic fields or electric field gradients (EFGs). In the case of quadrupolar electric interaction, the experimental measurement gives the quadrupolar frequency νQ with respective distribution δ as well as the asymmetry parameter η of EFG. The γ-γ PAC measurements were carried out using a standard set up with four conical BaF2 detector scintillators with a time resolution of 0.6 ns (FWHM).

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  • IPEN-DOC 27980

    MATOS, B.R. ; SILVA, J.S. da ; SCHADE, U.; PUSKAR, L.; FONSECA, F.C. . Identification of the polymer and electrode polarizations of Nafion dielectric spectrum. In: WORKSHOP ON ION EXCHANGE MEMBRANES FOR ENERGY APPLICATIONS, June 25-27, 2019, Bad Zwischenahn, Germany. Abstract... 2019.

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  • IPEN-DOC 27979

    MATOS, B.R. ; FONSECA, F.C. . Nafion dielectric polarization effects on the fuel cell I-V curve. In: WORKSHOP ON ION EXCHANGE MEMBRANES FOR ENERGY APPLICATIONS, June 25-27, 2019, Bad Zwischenahn, Germany. Abstract... 2019.

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  • IPEN-DOC 27978

    WATANABE, TAMIRES ; GUILHEN, SABINE N. ; MARUMO, JULIO T. ; ARAUJO, LEANDRO G. de . Uranium biosorption by hydroxyapatite and bone meal. In: AZEVEDO, DIANA C.S. de (Org.); BASTOS-NETO, MOISES (Org.) ENCONTRO BRASILEIRO DE ADSORÇÃO, 13th, November 25 - December 3, 2020, Online. Anais... Fortaleza, CE: Imprensa Universitária, 2021. p. 714-718. DOI: 10.51996/9786588492529

    Abstract: Biosorption has been widely examined for the treatment of aqueous solutions containing uranium, a radiotoxic pollutant. The use of hydroxyapatite and bone meal as potential biosorbents in the removal of uranium (U) from aqueous solutions has not yet been previously addressed. In this work, the efficiency of these biosorbents in the removal of U was investigated according to their adsorption removal capacities. Surface transformations in both materials were observed after U adsorption by scanning electron microscopy combined with energy-dispersive X-ray spectroscopy (SEM/EDS). The biomass/U solution ratio was kept at 0.1 g/5 mL. Contact times for the batch experiments were 15, 30, 60, 120, and 180 min, and the concentration of U tested was 680 mg L-1. The equilibrium was achieved in less than 15 min for both materials. The morphological characteristics of each biomass, before and after biosorption experiments were analyzed. Bone meal highlighted slightly superior adsorption results in terms of maximum capacity (qmax = 33.83 mg g-1), compared to hydroxyapatite (qmax = 33.36 mg g-1), with the removal percentages being also similar, 99.97 and 98.57 %, respectively. The results so far indicate that these materials are potential biosorbents for the treatment of uranium-contaminated solutions, especially liquid radioactive waste.

    Palavras-Chave: adsorption; uranium; bone tissues; apatites

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  • IPEN-DOC 27977

    VASQUEZ, P.A.S. ; MORAIS, F.; LIMA, F.S.; SANTOS, P.S. ; MORAES, O.; ARTAXO, P.; JOHN, V.M.; NAGAI, M.L.E.; OLIVEIRA, M.J.A. ; CATALANI, L.H.; KODAMA, Y. ; OTUBO, L. . Development of methodologies for decontamination, reuse and improvement of the properties of respiratory protective equipment using ionizing radiation: preliminary results. In: WEBINAR COVID-19 PANDEMIC: RADIATION STERILIZATION OF PPE (PERSONAL PROTECTIVE EQUIPMENT), May 21, 2020, Online. Apresentação... Vienna, Austria: International Atomic Energy Agency, 2020.

    Palavras-Chave: decontamination; equipment; radiation protection; ionizing radiations; safety

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  • IPEN-DOC 27976

    MORAES, L.P.R. ; MEI, J.; MARANI, D.; FONSECA, F.C. ; SUN, Z.. Wet-chemical synthesis of CeO2 for electrochemical applications. In: INTERNATIONAL CONFERENCE ON HIGH-PERFORMANCE CERAMICS, 11th, May 25-29, 2019, Kunming, China. Abstract... 2019.

    Abstract: Nanostructured metal oxides have been extensively studied in the last decades for their physicochemical properties, which depend on the size and shape of their nanostructures. The same chemical element or compound can exhibit different properties in different shapes and dimensions. Metal oxides are a class of inorganic compounds very important in many areas of materials science due to their unique properties that enable them to have a wide range of applications, such as sensor, catalysis, ceramics, absorbents and superconductors. They are particularly attractive for electrochemical applications due to their low molecular weight, favorable electrochemical properties and low toxicity, and have been extensively studied for the development of new energy conversion and storage systems, especially because of the higher electrode surface area, leading to higher charge/discharge rates, and their rich redox reactions involving different ions. Particularly, CeO2 is a promising metal oxide as it can present defects such as oxygen vacancies which play an important role for catalytic, magnetic and electrochemical properties. In this work, different nanostructures of CeO2 were synthesized by the selfassembly approach, from molecular precursors, using Pluronic P123 as surfactant and ethylene glycol as co-surfactant in ethanol solvent in a solvothermal system. The effect of different synthesis parameters on the morphology, crystallite size and electrochemical properties were investigated via various analytical techniques. The experimental results indicated that the synthesis parameters, such as temperature, aging time and chemicals concentration, strongly influences the morphology and sizes of CeO2, thus enabling the intentionally design of different nanomaterials.

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  • IPEN-DOC 27975

    FONSECA, FABIO C. ; MACHADO, MARINA F.S. ; MORAES, LETICIA P.R. ; RODRIGUES, THENNER S. ; KABIR, AHSANUL; MARANI, DEBORA; VAN NONG, NGO; ESPOSITO, VINCENZO. Controlling the sintering of ceria by shape-controlled synthesis of nanoparticles. In: INTERNATIONAL CONFERENCE ON HIGH-PERFORMANCE CERAMICS, 11th, May 25-29, 2019, Kunming, China. Abstract... 2019.

    Abstract: The influence of surface energy of Gd-doped CeO2 nanometric crystals with different morphologies on mass diffusion mechanisms is studied. Depending on the starting morphology (nanocubes, nanorods, and random nanoparticles) extremely different microstructures, ranging from rapidly densified to thermodynamically stable porous structures. We investigate Gd-doped ceria (10% molar, GDC) both for its relevance in several chemical, environmental and energy technologies, and because the extensive knowledge on diffusion effects ruling this compound. We synthesized GDC as nanocubes (NC) and nanorods (NR) by a hydrothermal method whereas randomly oriented nanoparticles (RD) were obtained by co-precipitation. All samples were measured as single phase GDC powders with narrow nanoparticle size distributions. The high surface area NR exhibit lower green density as compared to NC. Dilatometric analyses revealed that NR have a pronounced linear retraction starting at low temperatures (~200°C) with maximum sintering activity at ~1100°C. High surface energy in NRs leads to a rapid rod to sphere transformation as well as to a rapid densification despite relatively low green density. On the other hand, the solid state diffusion in NCs is significantly inhibited, as confirmed by the highly porous microstructure of sintered samples. The results indicated the possibility of controlling microstructure of GDC by defining the shape of nanoparticles for different application in which dense or stable pores are required.

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  • IPEN-DOC 27974

    IZIDORO, JULIANA ; FUNGARO, DENISE ; CAMPELLO, FELIPE ; GUILHEN, SABINE . Column leaching test for the evaluation of immobilization of toxic elements in modified coal fly ash. In: INTERNATIONAL WORKSHOP ADVANCES IN CLEANER PRODUCTION, 8th, November 13-15, 2019, Sanya, China. Abstract... São Paulo, SP: Advances in Cleaner Production Network, 2019. p. 64-65.

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  • IPEN-DOC 27973

    FOLHADELLA, KELLY C.F.; SILVA, IVES C. da; FREITAS, ANDERSON Z. de ; GARCEZ, AGUINALDO S.; NUNEZ, SILVIA C.. Estudo dose-resposta da atuação do laser de baixa potência sobre processo inflamatório induzido por carragenina em Zebrafish. In: CAMPATO JUNIOR, JOÃO A. (Org.) CONGRESSO ACADÊMICO E TECNOLÓGICO DA UNIVERSIDADE BRASIL, 1.; ENCONTRO DE INICIAÇÃO CIENTÍFICA, 14.; ENCONTRO DE PÓS-GRADUAÇÃO, 8., 04-05 de dezembro, 2020, Online. São José do Rio Preto, SP: HN Editora, 2020. p. 610-614.

    Abstract: Este estudo foi pensado para desenvolver uma alternativa de pesquisa mais acessível para que formas não farmacológicas de tratamento, como é o caso da fotobiomodulação, possam ser mais bem compreendidas e aprimoradas. Aqui, o zebrafish foi utilizado como modelo experimental para tratamento pela fotobiomodulação da inflamação induzida por carragenina. O tratamento da inflamação induzida foi feito com laser 660nm e a análise dos resultados realizada através de processamento histológico e OCT (Optical Coherence Tomography). A análise qualitativa dos resultados mostrou que o zebrafish representa um bom modelo alternativo e menos oneroso para o estudo da ação da fotobiomodulação sobre processos inflamatórios.

    Palavras-Chave: fishes; modulation; inflammation; lasers; therapeutic uses

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  • IPEN-DOC 27968

    CARDOSO, ELISABETH C.L. ; PARRA, DUCLERC F. ; SCAGLIUSI, SANDRA R. ; LUGAO, ADEMAR B. . Influence of particle size of bio-calcium carbonate used as reinforcement of PBAT/PLA bio-based foams compatibilized with ionizing radiation. Journal of Bioremediation & Biodegradation, v. 10, p. 42-42, 2019.

    Abstract: Bio-filler from eggshells as reinforcement of bio-based polymers are based on their principle benefits such as good strength and stiffness besides being an environmental friendly, degradable and renewable material. Eggshell is an agricultural waste largely considered as garbage and discarded mostly because it contributes to pollution. Biodegradable polymers as PLA (poli-lactic acid) and PBAT (butylene adipate co-terephthalate) are thermoplastics which can be processed using most conventional polymer processing methods. PLA is high in strength and modulus (63 MPa and 3.4 GPa, respectively) but brittle (strain at break 3.8%) while PBAT is flexible and tough (strain at break ~710%). In order to reduce interfacial tension exhibited by PLA/PBAT blend, compatibilization is fundamental: herein it was used as compatibilizing agent PLA previously e-beam irradiated at 150 kGy: ionizing radiation induces compatibilization by free radicals, improving the dispersion and adhesion of blend phases, without the use of chemical additives and at room temperature. PLA/PBAT, 65/35 blend with bio-filler, from avian eggs, of 38 and 75 µm particle size were prior homogenized in a co-rotating twin-screw extruder and further foamed in a mono-screw extruder, by using CO2 as Physical Blowing Agent (PBA). Characterizations involved: Melt Index, DSC, TGA, FTIR, SEM, XRD and mechanical essays.

    Palavras-Chave: calcium carbonates; biodegradation; eggs; polymers; fillers

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  • IPEN-DOC 27972

    NASCIMENTO, F.C. ; CALVO, W.A.P. . Proposal of LCA and Circular Economy concepts in the application, properties development and improvement from a premium acrylic emulsion added with aqueous dispersions of cellulosic residues treated by electron beam. In: INTERNATIONAL MEETING ON RADIATION PROCESSING, 19th, April 1-5, 2019, Strasbourg, France. Resumo expandido... 2019.

    Palavras-Chave: life cycle assessment; electron beams; paints; cellulose; aqueous solutions

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  • IPEN-DOC 27971

    KONDO, F.M. ; DUARTE, C.L. ; SOMESSARI, S.L. ; SATO, M.I. ; SALVADOR, V.L.R. ; LIMA, N.B. ; MARTINELLI, J.R. ; CALVO, W.A.P. . Extraction of molybdenum from spent cracking catalysts. In: INTERNATIONAL MEETING ON RADIATION PROCESSING, 19th, April 1-5, 2019, Strasbourg, France. Proceedings... 2019.

    Abstract: A catalyst is a substance that changes the rate of a reaction. In the petroleum industry, the catalysts are commonly used for Fluid Catalytic Cracking (FCC) and Hydro Catalytic Cracking (HCC), each of them applied in a specific stage. These catalysts are used to facilitate the molecular chains cracking, which will generate a mixture of hydrocarbons. However, the catalyst gradually loses its activity, either by changing its original molecular structure or by its contamination from other petroleum molecules. The application of ionizing radiation (medium-energy electron beam) over these spent catalysts was studied to contribute the extraction of metals or rare-earths of high added-value. Tests conducted with HCC catalysts were used the technique of electron beam irradiation (1.3 MeV) and had as a subject the extraction of Molybdenum. Energy Dispersive X-ray (EDX) analysis was performed on a Shimadzu EDX-720/800HS and X-ray Diffraction (XRD) analysis on a Rigaku MultiFlex. Electron beam irradiation had a positive contribution if compared to traditional thermal and chemical methods. In temperature around 750°C, HCC irradiated catalysts of the lower region have an extraction of Molybdenum (MoO3) yield twice higher compared to non-irradiated ones, in other words 57.65% and 26.24%, respectively.

    Palavras-Chave: catalytic cracking; molybdenum; electron beams; hydrocracking

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  • IPEN-DOC 27970

    GASPAR, R.R. ; SOMESSARI, S.L. ; SPRENGER, F.E. ; FEHER, A. ; DUARTE, C.L. ; SAMPA, M.H.O. ; LAINETTI, F.F. ; FUGA, D.F.; RODRIGUES, M.; CALVO, W.A.P. . Developing an electrical power system of a mobile electron beam accelerator to treat wastewater and industrial effluents. In: INTERNATIONAL MEETING ON RADIATION PROCESSING, 19th, April 1-5, 2019, Strasbourg, France. Proceedings... 2019.

    Abstract: The treatment of wastewater and industrial effluents by electron beam irradiation is a promising technique, however, not very widespread in Brazilian territory. The design and construction of a mobile unit by the Nuclear and Energy Research Institute, containing an electron beam accelerator of 700 keV and 20 kW is innovative to demonstrate the effects and positive results of this technology. The aim is to transfer the mobile unit to several companies with interest in liquid waste treatment, connect to the industry electrical system and start the ionization treatment process through electron beam. The mobile unit connection to the local electrical system may be a challenge due to the great diversity of voltages and distances involved, as well as the large injections of harmonic content generated by the electron beam accelerator that can affect sensitive loads in the industrial system. In this work, an analysis of the electrical power system of the mobile unit was made, regarding the interruption capacity, selectivity protection and adequate short circuit levels, in order to assure a greater reliability in the operation. At the end, the control panel of the mobile unit, simulations and measurements were carried out at the 1.5 MeV and 37.5 kW electron beam accelerator, installed in the Radiation Technology Center, demonstrating the necessity of applying a filter to reduce the measured harmonic distortion. The analysis of the mobile unit electrical power system was made, in order to assure a greater reliability in the operation.

    Palavras-Chave: waste water; liquid wastes; water treatment; electric power; accelerators; radiation sources; portable equipment; electron beams

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  • IPEN-DOC 27969

    LAINETTI, F.F. ; DUARTE, C.L. ; SOMESSARI, S.L. ; SPRENGER, F.E. ; FEHER, A. ; SAMPA, M.H.O. ; GASPAR, R.R. ; FUGA, D.; RODRIGUES, M.; CALVO, W.A.P. . Architectural design of a mobile irradiation unit for the treatment of industrial effluents in Brazil. In: INTERNATIONAL MEETING ON RADIATION PROCESSING, 19th, April 1-5, 2019, Strasbourg, France. Proceedings... 2019.

    Abstract: The Nuclear and Energy Research Institute (IPEN-CNEN/SP) decided to develop and build a mobile beam irradiation unit for the treatment of industrial effluents. The mobile unit will have as one of its main advantages the possibility of treating effluents in the place where the source is located, eliminating costs and bureaucratic problems associated with the transportation of waste, besides publicizing the technology in several places in Brazil. To implement the project, IPEN-CNEN/SP has been consolidating partnerships with national and international companies. The resources for the development of the unit have been supplied by the Brazilian Innovation Agency (FINEP) and International Atomic Energy Agency, financing the IAEA TC Project BRA1035 – Mobile electron beam accelerator to treat and recycle industrial effluents. The Institute hired a specialized company (Truckvan Industry) for the unit design and development. Several meetings have been realized with the company and the IAEA experts aiming the compatibility of the design and the exchange of information necessary for the project development. Regarding the mobile lab, several layout options have been developed to better meet the needs of each device and its users. The layout has been discussed with the objective of facilitating the maintenance of the equipment; the well-being and ergonomics of operators; optimization of spacing and also to make compatible the need for the presence of equipment and space for operators. Thus, several studies have been prepared to allow the discussion between the areas involved and to optimize the project, as well as the visualization of the spaces available. In this paper is presented the approach adopted for the architectural design of a mobile irradiation unit in Brazil.

    Palavras-Chave: waste water; liquid wastes; water treatment; accelerators; portable equipment; electron beams; radiation sources

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  • IPEN-DOC 27967

    PARRA, DUCLERC F. ; SILVA, ORELIO L. da ; KOMATSU, LUIZ G. ; CARDOSO, ELIZABETH C.L. ; LUGAO, ADEMAR B. . Nanocomposites foams of polypropilene modified by ionizing radiation containing CaCo3/ag° nanoparticles of bio-calcium carbonate-study of bactericidal effect. Journal of Bioremediation & Biodegradation, v. 10, p. 41-41, 2019.

    Abstract: This paper presents a study of high melting strengh polypropylene (HMSPP) foams by gamma irradiation with insertion of silver nanoparticles (AgNPs) adsorbed in carrier of CaCO3 (natural source) aiming bactericidal effect. The use of silver (Ag°) gives important antibacterial property since silver is highly toxic against bacterae. The HMSPP matrix was processed in a twin screw extruder under CO2 atmosphere and polypropylene nanocomposites (HMSPP-AgNC) were obtained in different concentrations of silver. The material was characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), field emission scanning electron microscopy (FESEM), X-ray diffraction spectroscopy (XRD), cytotoxicity assay and reduction colony-forming-unit (CFU). The analyzed foams showed spherical clusters and homogeneous regions with good distribution of the silver nanoparticles. Furthermore, the HMSPP@AgNCs foams exhibited a antibacterial efficiency against E. coli and S. aureus due to the presence of the biocidal silver nanoparticles.

    Palavras-Chave: germicides; sterilization; foams; polypropylene; gamma radiation; calcium carbonates

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  • IPEN-DOC 27966

    IZIDORO, JULIANA de C. ; BIBIANO, RAMIRO H. das N. ; LIMA, DANIELE de A.V. ; FUNGARO, DENISE A. . Gestão de resíduos sólidos agroindustriais e obtenção de produtos de valor agregado: uma perspectiva de desenvolvimento sustentável. In: SEMINÁRIO SAÚDE PLANETÁRIA NA AMÉRICA LATINA, 15-16 de dezembro, 2020, Online. Resumo... 2020.

    Abstract: As atividades da agroindústria estão gerando grandes quantidades de resíduos devido aos processos produtivos e alto padrão de consumo da sociedade. A maioria desses resíduos é descartada por queima, despejo ou aterramento causando impactos ambientais e na saúde humana. O conceito de aproveitamento de resíduos como componente da economia circular é uma alternativa para a disposição inadequada. A valorização de resíduos envolve a determinação das características físico-químicas por diferentes técnicas (FRX, DRX, MEV, etc). A etapa posterior consiste na aplicação de processos que transformam o resíduo em material de valor agregado. As cinzas provenientes da queima do bagaço da cana-de-açúcar são um dos principais resíduos gerados no Brasil. O alto teor de sílica possibilita a obtenção de silicato de sódio, nanosílica e zeólita. Esses produtos foram aplicados como material adsorvente e na produção de filmes biodegradáveis de amido. Resíduos lignocelulósicos (serragem, endocarpo de Macaúba) foram convertidos em biocarvão. As suas principais aplicações são como adsorvente e precursor de carvão ativado, além de apresentar potencial para o melhoramento das características ambientais de telhado verde. Dentre os resíduos inorgânicos, os produtos da combustão de carvão, compostos por sílica e alumina, são matéria-prima para obtenção de nanomateriais adsorventes como zeólita de alta pureza e tobermorita. Da mesma forma, o resíduo da reciclagem de alumínio pode ser usado na síntese de zeólita. A composição das cinzas sulfatadas geradas no processo úmido de dessulfurização indica seu potencial como aditivo no cimento e na formação de geopolímeros. Nessa abordagem, a adoção da economia circular na gestão de resíduos contribui significativamente para o cumprimento dos Objetivos de Desenvolvimento Sustentável (ODSs), especificamente, ODS 12: “Até 2030, reduzir substancialmente a geração de resíduos por meio da prevenção, redução, reciclagem e reuso”.

    Palavras-Chave: agricultural wastes; waste management; sustainable development; solid wastes

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  • IPEN-DOC 27965

    LOPES, FABIO ; YOSHIDA, ALEXANDRE ; CACHEFFO, ALEXANDRE ; SILVA, JONATAN ; MOREIRA, GREGORI ; LANDULFO, EDUARDO . Validation of AEOLUS L2A products using a multiwavelength lidar system at SPU Lidar Station - Brazil. In: AEOLUS CAL/VAL AND SCIENCE WORKSHOP, November 2-6, 2020, Online. Apresentação... 2020.

    Palavras-Chave: optical radar; aerosols; layers; earth atmosphere; wave propagation; satellite atmospheres

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  • IPEN-DOC 27964

    GATTI, LUCIANA V. ; BASSO, LUANA S.; MILLER, JOHN B.; GLOOR, MANUEL; DOMINGUES, LUCAS G. ; CASSOL, HENRIQUE L.G.; TEJADA, GRACIELA; ARAGAO, LUIZ E.O.C.; NOBRE, CARLOS; PETERS, WOUTER; MARANI, LUCIANO; ARAI, EGIDIO; SANCHES, ALBER H.; CORREA, SERGIO M.; ANDERSON, LIANA; VON RANDOW, CELSO; CORREIA, CAIO S.C. ; CRISPIM, STEPHANE P.; NEVES, RAIANE A.L.. Amazonia as a carbon source linked to deforestation and climate change. Nature, v. 595, n. 7867, p. 388-393, 2021. DOI: 10.1038/s41586-021-03629-6

    Abstract: Amazonia hosts the Earth’s largest tropical forests and has been shown to be an important carbon sink over recent decades. This carbon sink seems to be in decline, however, as a result of factors such as deforestation and climate change. Here we investigate Amazonia’s carbon budget and the main drivers responsible for its change into a carbon source. We performed 590 aircraft vertical profiling measurements of lower-tropospheric concentrations of carbon dioxide and carbon monoxide at four sites in Amazonia from 2010 to 2018. We find that total carbon emissions are greater in eastern Amazonia than in the western part, mostly as a result of spatial differences in carbon-monoxide-derived fire emissions. Southeastern Amazonia, in particular, acts as a net carbon source (total carbon flux minus fire emissions) to the atmosphere. Over the past 40 years, eastern Amazonia has been subjected to more deforestation, warming and moisture stress than the western part, especially during the dry season, with the southeast experiencing the strongest trends. We explore the effect of climate change and deforestation trends on carbon emissions at our study sites, and find that the intensification of the dry season and an increase in deforestation seem to promote ecosystem stress, increase in fire occurrence, and higher carbon emissions in the eastern Amazon. This is in line with recent studies that indicate an increase in tree mortality and a reduction in photosynthesis as a result of climatic changes across Amazonia.

    Palavras-Chave: climatic change; burns; carbon sources; emission; deforestation; troposphere; temperature measurement; environmental impacts; amazon river

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  • IPEN-DOC 27963

    ABE, ALFREDO ; TEIXEIRA, ANTONIO ; SOUZA, DANIEL ; GIOVEDI, CLAUDIA. Preliminary assessment of iron alloy cladding as accident tolerant fuel cladding. In: TECHNICAL MEETING ON MODELLING OF FUEL BEHAVIOUR IN DESIGN BASIS ACCIDENTS AND DESIGN EXTENSION CONDITIONS, May 13-16, 2019, Shenzhen, China. Apresentação... 2019.

    Palavras-Chave: waste water; liquid wastes; industrial wastes; accelerators; portable equipment; electron beams

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  • IPEN-DOC 27962

    APITULEY, ARNOUD; KREHER, KARIN; PITERS, ANKIE; SULLIVAN, JOHN; VAN ROOZENDAEL, MICHEL; VLEMMIX, TIM; DEN HOED, MIRJAM; FRUMAU, ARNOUD; HENZING, BAS; SPEET, BART; VONK, JAN; VEEFKIND, PEPIJN; ALVES, DIEGO ; CACHEFFO, ALEXANDRE ; STEIN-ZWEERS, DEBORAH; ALLAART, MARC; ESKES, HENK; VAN DER ENT, FLORIS; SALEEB, GEORGE; MCGEE, TOM; TWIGG, LARRY; SUMNICHT, GRANT; HENDRICK, FRANCOIS; MERLAUD, ALEXIS; FAYT, CAROLINE; HERMANS, CHRISTIAN; PINARDI, GAIA; DORNER, STEFFEN; WAGNER, THOMAS; LAUSTER, BIANCA; UBELE, ALMA; MENDES, ALEX ; LOPES, FABIO ; LANDULFO, EDUARDO ; SPINEI, ELENA; QUEREL, RICHARD; KARAGKIOZIDIS, DIMITRIS; BAIS, ALKIS; HUTJES, RONALD. Overview of the 2019 Sentinel-5p TROpomi vaLIdation eXperiment (TROLIX). In: EGU GENERAL ASSEMBLY, May 4-8, 2020, Online. Abstract... Göttingen, Germany: Copernicus, 2020.

    Abstract: For the validation of Sentinel-5p/TROPOMI the TROpomi vaLIdation eXperiment (TROLIX) was held in the Netherlands based at the Cabauw Experimental Site for Atmospheric Research during September 2019. TROLIX consisted of active and passive remote sensing platforms in conjunction with several balloon-borne and surface measurements. The intensive observations will serve to establish the quality of TROPOMI L2 main data products (UVAI, Aerosol Layer Height, NO2, O3, HCHO, Clouds) under realistic conditions with varying cloud cover and a wide range of atmospheric conditions. Since TROPOMI is a hyperspectral imager with a very high spatial resolution of 3.6 x 5.6 km2, understanding local effects such as inhomogeneous sources of pollution, sub-pixel clouds and variations in ground albedo is important to interpret TROPOMI results. Therefore, the campaign included sub-pixel resolution local networks of sensors, involving MAXDOAS and Pandora instruments, around Cabauw (rural) and within the city of Rotterdam (urban). Utilising its comprehensive in-situ and remote sensing observation program in and around the 213 m meteorological tower, Cabauw was the main site of the campaign with focus on vertical profiling using lidar instruments for aerosols, clouds, water vapor, tropospheric and stratospheric ozone, as well as balloon-borne sensors for NO2 and ozone. The data set collected can be directly compared to the TROPOMI L2 data products, while measurements of parameters related to a-priori data and auxiliary parameters that infuence the quality of the L2 products such as aerosol and cloud profiles and in-situ aerosol and atmospheric chemistry were also collected.

    Palavras-Chave: satellites; orbits; ozone; monitoring; atmospheric chemistry

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  • IPEN-DOC 27961

    GATTI, LUCIANA V. ; DOMINGUES, LUCAS G. ; BASSO, LUANA S. ; MILLER, JOHN B.; CASSOL, HENRIQUE L.G.; MARANI, LUCIANO; CORREIA, CAIO S. de C. ; TEJADA, GRACIELA; ARAGAO, LUIZ E.O.C.; ANDERSON, LIANA O.; GLOOR, MANUEL; PETERS, WOUTER; VON RANDOW, CELSO; NEVES, RAIANE A.L.; IPIA, ALBER; CRISPIM, STEPHANE P.; ARAI, EGIDIO. Sensitivity of Amazon Carbon Balance to climate and human-driven changes in Amazon. In: AGU CHARPMAN CONFERENCE, August 26-29, 2019, San Diego, CA, USA. Abstract... Washington, DC, USA: American Geophysical Union, 2019.

    Abstract: Amazon is the major tropical land region, with critical processes, such as the carbon cycle, not yet fully understood. Only very few long-term greenhouse gas measurements is available in the tropics. The Amazon accounts for 50% of Earth’s tropical rainforests hosting the largest carbon pool in vegetation and soils (~200 PgC). The net carbon exchange between tropical land and the atmosphere is critically important because the stability of carbon in forests and soils can be disrupted in short time-scales. The main processes releasing C to the atmosphere are deforestation, fires and changes in growing conditions due to increased temperatures and droughts. Such changes may thus cause feedbacks on global climate. In the last 40 years, Amazon mean temperature increased by 1.1ºC. The length of the dry season is also increasing. We observed a reduction of 50.5mm in the annual mean precipitation during this same 40 years period. Precipitation reduction occurred mainly in the dry season, exacerbating vegetation water stress with consequences for the carbon balance. To understand the consequences of climate and human-driven changes on the C budget of Amazonia, we put in place the first program with regional representativeness, from 2010 onwards, aiming to quantify greenhouse gases based on extensive collection of vertical profiles of CO2 and CO. Regular vertical profiles from the ground up to 4.5 km height were performed at four sites along the main air-stream over the Amazon. Here we will report what these new data tell us about the greenhouse gas balance and its controls during the 2010-2017. Along this period we performed 513 vertical profiles over four strategic regions that represent fluxes over the entire Amazon region. The observed variability of carbon fluxes during these 8 years is correlated with climate variability (Temperature, precipitation, GRACE) and human-driven changes (Biomass Burning). The correlations were performed inside each influenced area for each studied site. It was observed a persistent C source from the Amazon (natural plus anthropogenic sources) to the atmosphere. Amazon was a consistent source of 0.4 ± 0.2 PgC/year on average considering the Amazon area of 7.2 million km2. Fire emission is the main source of carbon to the atmosphere, which is not compensate by the C removal from old-growth Amazon forest.

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  • IPEN-DOC 27960

    TEJADA, GRACIELA; GATTI, LUCIANA V. ; BASSO, LUANA S.; MARANI, LUCIANO; CASSOL, HENRIQUE L.G.; CRISPIM, STEPHANE P.; NEVES, RAIANE A.L.; DOMINGUES, LUCAS G. ; IPIA, ALBER; CORREIA, CAIO S. de C. ; ARAI, EGIDIO; GLOOR, EMANUEL U.; MILLER, JOHN B.; VON RANDOW, CELSO. Land use and cover change and CO2 atmospheric measurements in the Amazon forests. In: AGU CHARPMAN CONFERENCE, August 26-29, 2019, San Diego, CA, USA. Abstract... Washington, DC, USA: American Geophysical Union, 2019.

    Abstract: In the last years, global CO2 concentrations have reach levels never seen before reaching more than 400 ppm. Among the main causes of these emissions are the burning of fossil fuels and the land use and cover change (LUCC) related emissions. In the Amazon region, the main CO2 emissions are related to deforestation. Multitemporal LUCC datasets have been restrict to Brazil, but now has been released a pan-Amazon dataset for all the countries sharing the Amazon, opening the possibility of studying the Amazon forests as a whole. On the other hand, the lower-troposphere greenhouse gas (GHG) monitoring program “Carbam project”, has been collecting biweekly GHGs vertical profiles in four sites of the Amazon since 2010, filling a very important gap in regional GHGs measurements. Our purpose is to understand the relationships between regional LUCC and CO2 aircraft measurements in the Amazon. Here we present the relationships between annual LUCC data from 2010 to 2017 in the Amazon forest and in each mean influence area of Carbam sites comparing them with mean annual CO2 fluxes. Considering the whole Amazon forests and the mean annual CO2 fluxes, the years with more forest loss and agriculture increase are 2010 and 2016, showing relation with CO2 fluxes. On the other hand, 2011 and 2017 also have deforestation (less than 2010 and 2016), but the CO2 fluxes are lower, showing that droughts could also influence the CO2 concentrations. Looking at each influence area, total carbon flux of Alta Floresta and Rio Branco have the same tendency as the forest loss from 2013 to 2017, but no in 2010 and 2012. In Tabantinga, Tefé and Santarem there is no a direct relationship between the carbon fluxes and the forest loss. To understand better the relationships at each site, we have to consider the years of measurements. Also, the temporal scale, carbon fluxes are measure biweekly and the LUCC data is annual. Looking at the potentialities and limitations of this relationship, it will be possible to improve the methodology to better understand the interaction of human activities and CO2 emissions on the carbon balance.

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  • IPEN-DOC 27959

    CASSOL, HENRIQUE L.G.; DOMINGUES, LUCAS G. ; BASSO, LUANA S. ; GATTI, LUCIANA V. ; MARANI, LUCIANO; TEJADA, GRACIELA; CRISPIM, STEPHANE P.; NEVES, RAIANE A.L.; CORREIA, CAIO S. de C. ; ARAI, EGIDIO; GLOOR, MANUEL; MILLER, JOHN B.; ANDERSON, LIANA O.; ARAGAO, LUIZ E.O.C.. Increasing of carbon emission from biomass burning due to the temperature rising and precipitation reduction in the Amazon. In: AGU CHARPMAN CONFERENCE, August 26-29, 2019, San Diego, CA, USA. Abstract... Washington, DC, USA: American Geophysical Union, 2019.

    Abstract: Recent droughts have increased the magnitude and frequency of the forest fires in the Amazon (Aragão et al. 2018). As a consequence, the Amazon has become a Carbon source due to the rising of the Carbon emission from biomass burned in the El Niño events. Faced with climate change and the likely acceleration of temperature in tropical regions, we hypothesize that Amazon will become a Carbon source even in non-droughts years, due to the increase of forest fires. Therefore, we compared 7 years of atmospheric profiles of CO2 obtained from aircraft overfly at four sites of the Amazon, since 2010, with temperature, precipitation, and fire counts (FC). Carbon emission from fires was obtained by the ratio of CO/CO2 and differs by site and year. The FC and climatic variables were extracted from quarterly influence areas by site and weighted by the amount of trajectories within a cell of one degree resolution. The fire emissions released by the Amazon is about 0.38 ± 0.086 Pg.C.yr-1, which represent roughly 17% of the annual global fires emissions (Werf et al. 2017). However, there are markedly divergences in the Fire emissions across Amazon. For instance, the emission from the Eastern is 400% higher and account of an average 60% more FC than observed in the Western. FC were positively and significantly correlated with Carbon from fires at all sites (ρ = 0.55-0.83, α = 0.05, p-value<0.001), being higher in the Southeastern of Amazon (Alta Floresta and Santarém sites), and lower in the Northwest of Amazon (Tefé site and Rio Branco Sites). This discrepancy may occur due to the Southeastern of Amazon be located inside the “Arc of deforestation” where the dynamic of the Land-Use Land-Cover Change is more pronounced. We also found a strong relationship between FC and temperature and precipitation (r² adj = 0.44-0.67, p-value<0.001). Temperature is positively correlated with FC and explains circa of 90% of their variability in the linear model (r² partial = 0.4-0.59, α = 0.05, p-value<0.001). It means that an increase of one degree (1°C) in the Amazon represents an increase of about 13600 fire counts; and the reduction of 100 mm precipitation means an increase of 315 in the fire counts. In the balance of the Fire emissions, it would add 1.27 Pg Pg.C.yr-1 at each degree celsius of increase and 0.2 Pg.C.yr-1 at each 100 mm of precipitation reduction.

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  • IPEN-DOC 27958

    BASSO, LUANA S.; GATTI, LUCIANA V. ; MARANI, LUCIANO; CASSOL, HENRIQUE L.G.; TEJADA, GRACIELA; DOMINGUES, LUCAS G. ; CORREIA, CAIO S. de C. ; IPIA, ALBER; ARAI, EGIDIO; ARAGAO, LUIZ E.O.C.; ANDERSON, LIANA O.; CRISPIM, STEPHANE P.; NEVES, RAIANE A.L.; GLOOR, MANUEL; MILLER, JOHN B.. Understanding the seasonality and interannual variability of Amazon CH4 budget and climate feedbacks based on atmospheric data from vertical profiles measurements. In: AGU CHARPMAN CONFERENCE, August 26-29, 2019, San Diego, CA, USA. Abstract... Washington, DC, USA: American Geophysical Union, 2019.

    Abstract: Currently tropical land regions, like Amazon, are still poorly observed with large-scale integrating in-situ observations although they host some of the largest wetlands/seasonally flooded areas on the globe. The role of these regions in the global CH4 balance and the climate feedbacks have remained uncertain. To help this situation we have started a lower-troposphere greenhouse gas-monitoring program over tropical South America consisting of regular vertical profile greenhouse gas and carbon monoxide (CO) observations at four sites along the main airstream since 2010. Vertical profiles are sampled using light aircraft, high-precision greenhouse gas and carbon monoxide analysis of flask air, fortnightly between 2010 to 2017. Over the full period the Amazon (total area of around 7.2 million km2) was a source of CH4, of approximately 46 ± 6 Tg/year, which represent 8% of the global CH4 flux to the atmosphere. CH4 emissions from different parts of the basin vary markedly. There are comparably high emissions from the eastern part of the basin exhibiting strong variability, with particularly high CH4 fluxes in the early part of the wet season (January to March). A second period of high emissions occurs during the dry season. The cause of the high emissions is unclear. In contrast to the eastern Amazon site a clear seasonality was observed at the other three sites located further downwind along the main sir-stream, with the largest emissions occurring at the beginning of the wet season (January to March). In addition, these data show an interannual variability in emissions magnitude, so we discuss how these data can be correlate to temperature, precipitation, terrestrial water storage anomalies (from GRACE) and Fire counts (human-driven changes) that could be influencing this variability. Using a CO/CH4 emission ratio calculated in this study we find a biomass burning contribution varying between 10 and 23% of the total flux at each site. Also, we discuss what the data tell us about possible ongoing feedbacks to possible changes in temperature, precipitation and biomass burning and indicating what variables can be contributing to CH4 emissions from Amazon.

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  • IPEN-DOC 27957

    KORKISCHKO, IVAN ; MAFFEI, FELIPE S.; GIORIA, RAFAEL dos S.; MENEGHINI, JULIO R.. Geometric parameter optimization of a liquid jet liquid ejector. In: ANNUAL MEETING OF THE APS DIVISION OF FLUID DYNAMICS, 72nd, November 23-26, 2019, Seattle, Washington, USA. Abstract... Maryland, USA: American Physical Society, 2019.

    Abstract: Ejectors are devices employed as pumps or compressors, which work transferring momentum from a primary fluid (high pressure) to a secondary fluid (low pressure). On the one hand, their main advantages over standard pumps and compressors are no moving parts, no need of lubricants and seals, and low noise and maintenance. On the other hand, ejectors have low efficiency compared to other devices and a very narrow region of optimal operation. Thus, ejectors certainly benefit from optimization studies. This investigation was based on a CFD model of a liquid jet liquid (LJL) ejector. The finite element method was used, coupled with the k-epsilon turbulence model. The optimization study had three steps. First, the constants of the turbulence model were recalibrated to minimize the difference between the numerical and experimental efficiency curves. Second, using the main geometric parameters as control variables, the peak efficiency was maximized. Finally, the optimized geometry was further improved, considering the transitions between the different ejector components, which were originally sharp corners. The optimized round corners increased the ejector efficiency.

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  • IPEN-DOC 27956

    AYLLON, RAFAELLA M. ; EL HAJJ, THAMMIRIS M.; SILVA, PAULO S.C. da ; TORQUATO, HENRIQUE; SCAPIN, MARCOS A. ; GARCIA, RAFAEL H.L. . Radiological and mineralogical characterization of the tailings of a niobium ore treatment plant in Brazil. In: INTERNATIONAL SYMPOSIUM ON NATURALLY OCCURRING RADIOACTIVE MATERIAL, 9th, September 23-27, 2019, Denver, Colorado, USA. Apresentação... 2019.

    Palavras-Chave: niobium ores; industrial plants; mineral industry; natural radioactivity; radiation hazards; trace amounts

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  • IPEN-DOC 27955

    VAN VELZEN, LEO; DRAGOLICI, FELICIA; ROBINS, REBECCA; MARUMO, JULIO T. ; FERNANDO, KAPILA; VANLSEGHEM, PIERRE; KASHIWAGI, MAKOTO. IAEA LABONET - International Network for Radioactive Waste Characterization - Support of the non-nuclear industry at the characterization of NORM. In: INTERNATIONAL SYMPOSIUM ON NATURALLY OCCURRING RADIOACTIVE MATERIAL, 9th, September 23-27, 2019, Denver, Colorado, USA. Apresentação... 2019.

    Palavras-Chave: radioactive waste management; nuclear energy; knowledge management; international organizations; international cooperation

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  • IPEN-DOC 27954

    MAZZILLI, BARBARA ; SAUEIA, CATIA ; NISTI, MARCELO . Radiological implications of using phosphogypsum as soil conditioner: a case study of Brazil. In: INTERNATIONAL SYMPOSIUM ON NATURALLY OCCURRING RADIOACTIVE MATERIAL, 9th, September 23-27, 2019, Denver, Colorado, USA. Apresentação... 2019.

    Palavras-Chave: phosphates; gypsum; fertilizers; soils; agriculture; chemical composition; radiation hazards; radioisotopes

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  • IPEN-DOC 27953

    CAMPOS, MARCIA P. de ; NISTI, MARCELO B. ; PASCHOALIN FILHO, JOAO A.; MAZZILLI, BARBARA P. . Radiological evaluation of bricks made with NORM residue. In: INTERNATIONAL SYMPOSIUM ON NATURALLY OCCURRING RADIOACTIVE MATERIAL, 9th, September 23-27, 2019, Denver, Colorado, USA. Apresentação... 2019.

    Palavras-Chave: radioactive materials; residues; building materials; phosphates; gypsum; radioactivity

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  • IPEN-DOC 27952

    MOREIRA, EDSON G. ; SILVA, PAULO S.C. ; MAIHARA, VERA A. ; TAPPIZ, BRUNO ; NISTI, MARCELO B. ; SAUEIA, CATIA H.R. ; CARVALHO, RICARDO N. . Naturally occurring radionuclides in a fish reference material. In: INTERNATIONAL SYMPOSIUM ON NATURALLY OCCURRING RADIOACTIVE MATERIAL, 9th, September 23-27, 2019, Denver, Colorado, USA. Apresentação... 2019.

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  • IPEN-DOC 27951

    CARVALHO, PATRICIA R. ; MUNITA, CASIMIRO S. ; NEVES, EDUARDO G.; ZIMPEL, CARLOS A.. A provenance assessment of ancient pottery through instrumental neutron activation analysis at the Monte Castelo site, Rondônia, Brazil. In: INTERNATIONAL CONFERENCE ON MODERN TRENDS IN ACTIVATION ANALYSIS, 15th, November 17-22, 2019, Mumbai, India. Proceedings... 2019.

    Abstract: This research aims to contribute to the discussion of ceramic objects found at the Monte Castelo shell mound (sambaqui), an archaeological site located at south west Amazonia, Brazil. The first study performed in the area in the 1980s suggests that this archaeological site is inserted within one of the oldest contexts of ceramic production in Amazonia. Until today, there have not been any studies of the physical and chemical properties of these objects to reconstruct clay procurement practices and contribute to their archaeological interpretation. With this purpose, this paper provides the results of a preliminary chemical characterization of eighty four pottery samples using instrumental neutron activation analysis (INAA) by means of the determination of Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Rb, Sc, Sm, Th, U, Yb and Zn. The compositional analysis produced substantial geochemical data that allowed comparisons of the similarity/dissimilarity between the samples by means of cluster, principal components and discriminant analysis. The results showed the existence of three different chemical groups whose dates range from 3,000 B.P. to 1,500 B.P. and are in agreement with other studies that place the Bacabal phase as the oldest ceramist culture in the Southwest of the Amazon. Additionally, this study provided a solid research framework of investigation that can be employed for more detailed and extensive future studies on ancient human occupation in the research area.

    Palavras-Chave: archaeological sites; neutron activation analysis; sediments; chemical composition; geologic deposits

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  • IPEN-DOC 27950

    TUDELA, DIEGO R.G. ; ARAUJO, ASTOLFO G.M.; TATUMI, SONIA H.; MITTANI, JUAN C.R.; MUNITA, CASIMIRO S. . Preliminary evidence of prehistoric human activity by chemical analysis of sediments from Lapa Grande de Taquaraçu archaeological site using INAA. In: INTERNATIONAL CONFERENCE ON MODERN TRENDS IN ACTIVATION ANALYSIS, 15th, November 17-22, 2019, Mumbai, India. Proceedings... 2019.

    Abstract: This paper analyzes the concentrations of Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn determined from sixty sediment samples obtained from the Lapa Grande de Taquaraçu archaeological site using instrumental neutron activation analysis, INAA. The archaeological site is located inside a limestone rockshelter in the municipality of Jaboticatubas, about 60 km from Belo Horizonte, Minas Gerais State, Brazil. The dataset was explored by means of cluster analysis, principal component analysis and discriminant analysis. The study showed three different compositional groups that represent sediments from fluvial, colluvial and anthropogenic origins. The crystalline phases of each group were studied using X-ray diffraction, XRD.

    Palavras-Chave: sediments; cluster analysis; charged-particle activation analysis; chemical state; elements; isotope ratio; neutron activation analysis

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  • IPEN-DOC 27949

    AMARAL, MARCELLO M.; DEL-VALLE, MATHEUS ; RAELE, MARCUS P. ; PRETTO, LUCAS R. de . Laser speckle imaging for osteoporosis evaluation. In: ENCONTRO DE OUTONO DA SOCIEDADE BRASILEIRA DE FÍSICA, 43., 23-26 de novembro, 2020, Online. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2020.

    Abstract: Osteoporosis is a common disease characterized by the reduction on Bone Mineral Density (BMD), leading to weakening of bone structure, Chronic pain, deformities and loss of quality of life. In addition to the clinical evaluation, dual-energy X-ray absorptiometry is one of the main techniques to diagnose it. However, this technique uses ionizing radiation to assess the bone structure and therefore cannot be used very often by patients, due to radiological safety reasons. On the other hand, optical techniques are known for its safe use, due to non-ionizing radiation, however, optical techniques do not easily allows the analysis of bone tissue. This limitation could be circumvented in the oral cavity area. In this work we used the Laser Speckle Imaging (LSI) technique to evaluate maxilla and mandible bones after demineralization prosses in an animal in vitro model. Osteoporosis lesions were simulated in sixteen mandible and twelve maxilla slabs using Ethylenediaminetetraacetic Acid (EDTA) 0.5 M for 0 (control) 7, 15 and 30 days. The roughness parameters Ra and Rq were analyzed with optical profilometry (ZeGage, Zygo, USA) to characterize the demineralization process. The LSI images were measured by custom experimental setup. A collimated laser beam at 635 nm and 1.3mW (Thorlabs CPS635R), expanded by a diverging lens (-75 mm), illuminates the sample. The scattered signal was imaged by a CCD camera (Thorlabs - DCC1645-HQ), an adapter (Thorlabs MVLCMC) and objective lens (Thorlabs/Navitar - MVL12X3Z) setting. A custom software was implemented to measure the speckle patches ratio and the speckle contrast ratio from speckle images obtained by a custom LSI setup. The speckle contrast ratio method only differentiate sound from osteoporotic tissue. The speckle patches ratio method presented a negative correlation with the roughness parameter, and consequently with the demineralization level. It was concluded that LSI is a promissory technique for assessment osteoporosis lesions on alveolar bone and, for that, the patches ratio is the best methodology for detecting and differentiating several degrees of demineralization.

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  • IPEN-DOC 27948

    VALENCA, J.V.B.; ANTONIO, P.L. ; CALDAS, L.V.E. ; SILVA, A.C.A.; DANTAS, N.O.; D'ERRICO, F.; SILVEIRA, I.S.; SOUZA, S.O.. Optically stimulated luminescence of different borate glass compositions. In: ENCONTRO DE OUTONO DA SOCIEDADE BRASILEIRA DE FÍSICA, 42., 26-31 de maio, 2019, Aracaju, SE. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2019.

    Abstract: Radiation detection applications are pointed out as one of the emerging research areas in glass science. Borate glass presents desirable characteristics for dosimetric applications. The main goal of this work was to analyze the optically stimulated luminescence (OSL) signal for different lithium borate glasses containing magnesia (LMB), quicklime (LCB) or potassium carbonate (LKB). Five different glass formulations were produced for each batch. All formulations were produced by using a melt-quenching method and analyzed in terms of both dose-response and OSL shape decay after submitted to beta irradiation. Pre-heating treatments were also used in the OSL analysis of the samples. The X-ray diffractometry (XRD) and differential thermal analysis (DTA) confirmed the glassy state of the produced samples. In our research, we observed that glass modified with potassium, LKB, is more sensitive to radiation compared with samples produced with magnesium and calcium. Regarding the study done with the LKB formulations, differences in the sensitivity ranking were observed as we either analyzed the OSL signal based on the integrated signal or the emission in the very first 0.16 s. A comparison of this difference was extended to all formulations in the LKB group, which showed that the parameter used to plot the dose-response curve has to be considered in the process of analyzing glassy materials, as it can influence in possible applications. Pre-heating studies also showed tendencies for the studied compositions that were already discussed in the specialized literature for phosphate glass.

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  • IPEN-DOC 27947

    SILVA, ANDERSON M.B.; SOUZA, DIVANIZIA N.; JUNOT, DANILO O. ; CALDAS, LINDA V.E. . Thermoluminescent analysis of silver addition in CaSO4 : Tb. In: ENCONTRO DE OUTONO DA SOCIEDADE BRASILEIRA DE FÍSICA, 42., 26-31 de maio, 2019, Aracaju, SE. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2019.

    Abstract: According to results of the literature, some unusual rare earth elements, such as terbium, have been shown to be promising as a dopant in CaSO4 matrix. Silver has also been used in the co-dopant function. As there are no reports on the structural characterization of CaSO4 : Tb with the incorporation of silver, the aim of this work was to produce and characterize terbium doped CaSO4 crystals, co-doped with silver oxide (Ag (Ox)) and silver nanoparticles (Ag (NP)). The main purpose is to use them as alternative TL dosimeters to those commercially available. The phosphors were produced by the slow evaporation route and characterized by X-ray diffraction (XRD), which confirmed the viability of the route, and by scanning electron microscopy (SEM). The silver nanoparticles were produced by the method of Lee and Meisel and characterized by ultraviolet-visible spectrophotometry (UV-Vis), SEM and XRD. The composites in the form of pellets were obtained from the addition of Teflon to the phosphors. The TL emissions of the new materials produced were investigated. It was observed that the addition of silver as a co-dopant in the CaSO4 : Tb matrix shifts its main TL peak to higher temperatures, and the presence of Ag (NP) increases the intensity of this peak. By means of the TL emission curves of the composites, some parameters associated with the charge transfer processes in these materials were determined. The lower detection limit of the composites was also evaluated. The crystals of CaSO4 : Tb; Ag(NP) presented higher sensitivity than CaSO4 : Tb; Ag(Ox). All samples have a luminescent signal reproducible and linear, with TL responses proportional to the absorbed doses.

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  • IPEN-DOC 27946

    POLO, IVON O. ; CALDAS, LINDA V.E. ; SANTOS, WILLIAM S. . Monte Carlo approach for the determination of the angular dependence of an extrapolation chamber response. In: ENCONTRO DE OUTONO DA SOCIEDADE BRASILEIRA DE FÍSICA, 42., 26-31 de maio, 2019, Aracaju, SE. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2019.

    Abstract: The angular dependence of an extrapolation chamber response is reported. The determination of the angular factors were carried out using the MCNP Monte Carlo Method. To determine the angular dependence, the PTW type 23392 extrapolation chamber of the Laboratory for Calibration of Instruments (LCI/IPEN) was simulated. The experiments were performed for the radiation fields of beta secondary standard BSS2 system sources. For the 90Sr/90Y source, the calibration distance of 11 cm without the beam flattening filter was used. For the 85Kr and 147Pm sources, the distances of 30 cm and 20 cm with the filter were used, respectively. The simulations were carried out by rotating the extrapolation chamber around the reference axis for angles between -90º and 90º, in steps of 5º. For the 90Sr/90Y source the angular dependence factor is greater than 1, predominating the dose build-up effect up to 60º and -60º, and the factor is less than 1 for the other angles, prevailing the absorption of beta particles. For the 85Kr and 147Pm sources, the angular dependence factor is less than 1 for all angles, predominating the absorption of beta particles too. The determined angular factors are in good agreement with the international report ISO 6980.

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  • IPEN-DOC 27937

    PARRA, V.; PARRA, D.F. ; SANTOS, V. . Comparação da liberação de neomicina entre um hidrogel e um argilogel. In: WORKSHOP DE BIOMATERIAIS, ENGENHARIA DE TECIDOS E ORGÃOS ARTIFICIAIS, 6th, October 29-31, 2019, São Paulo, SP. Abstract... São Paulo, SP, 2019. p. 360-360.

    Abstract: Os hidrogéis poliméricos são sistemas naturais ou sintéticos, que ganharam interesse devido à sua alta biocompatibilidade com tecidos moles. Estes tipos de hidrogéis têm sido utilizados para curativos como um sistema de entrega de medicamentos. No presente estudo os sistemas de cicatrização de feridas baseadas em hidrogéis poliméricos foram preparados usando poli (N-vinil-2-pirrolidona) (PVP), poli (etilenoglicol) (PEG), ágar e neomicina droga seguida de irradiação gama para promover reticulação e esterilização. A influência do processo de irradiação com dose de 25 kGy foi investigada. A fração gel e intumescimento máximo foram estimados usando métodos físico-químicos e constatou-se a ocorrência de cerca de 95% de fração de gel, relativa a polímero reticulado; e intumescimento de 1100% após 8 horas de imersão. A neomicina liberada do hidrogel foi avaliada por cromatografia líquida com identificação por Espectrometria de Massa. Trabalhos realizados no IPEN atestaram que a neomicina foi liberada em cerca de 8h e a concentração da droga permaneceu constante por 48 h. Já no caso de argilogéis a liberação é mais lenta em razão da presença da argila e depende da concentração da mesma. O hidrogel / neomicina exibiu efeitos antibacterianos contra o Staphylococcus aureus. Com estes resultados, pode-se inferir que o sistema hidrogel / neomicina é um candidato potencial para compor curativos de feridas.

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  • IPEN-DOC 27945

    OLIANI, WASHINGTON L. ; KOMATSU, LUIZ G.H. ; LUGAO, ADEMAR B. ; PARRA, DUCLERC F. . Films of polyethylene-AgNPs: state-of-the-art, ecotoxicological aspects and antimicrobial efficacy. In: CONGRESSO BRASILEIRO DE POLÍMEROS, 15., 27-31 de outubro, 2019, Bento Gonçalves-RS. Anais... São Carlos, SP: Associação Brasileira de Polímeros, 2019. p. 2641-2644.

    Abstract: In recent years, antimicrobial packaging has attracted much attention from the food industry because of the increase in consumer demand for minimally processed, preservative-free-products. Different grades of polyethylene, LLDPE and LDPE play a major role in the film blowing industry and are widely used for packing applications. In our study, blown films of LLDPE / LDPE, and their blends were produced using a twin screw extruder. The combination of PEs as matrix, and silver nanoparticles with oleic acid solution, improved the AgNPs dispersion in the films. The films were evaluated by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDX), and Ecotoxicity. Further, the antibacterial properties of the films were investigated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria.

    Palavras-Chave: polyethylenes; silver; nanoparticles; oleic acid; antimicrobial agents

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  • IPEN-DOC 27944

    KOMATSU, LUIZ G.H. ; OLIANI, WASHINGTON L. ; LUGAO, ADEMAR B. ; PARRA, DUCLERC F. . Aplicação de ZnO como carregador de prata em uma blenda de HMSPP/SEBS visando ação biocida / Aplication of ZnO as carrier of silver in the blend of HMSPP/SEBS for biocide activity. In: CONGRESSO BRASILEIRO DE POLÍMEROS, 15., 27-31 de outubro, 2019, Bento Gonçalves-RS. Anais... São Carlos, SP: Associação Brasileira de Polímeros, 2019. p. 2356-2359.

    Abstract: Este estudo consiste em utilizar o óxido de zinco (ZnO) como carregador de nanoprata metálica (Ag°). Foi testado um método para síntese das partículas com a prata, o método de Turkevich. A confecção dos filmes poliméricos em matriz de HMSPP/SEBS foi realizada via processamento no estado fundido em extrusora. Os materiais obtidos foram caracterizados pelas técnicas de DLS, MEV e ensaios biocidas. As partículas apresentaram-se em tamanhos variando entre 100 à 200 nm, juntamente a isso, elas também apresentaram resultados de morte celular nos ensaios biocidas com as bactérias E.coli e S.aureus de acordo com a norma JIZ 2801.

    Palavras-Chave: films; polymers; zinc oxides; nanoparticles; silver; disinfectants; bacteria

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  • IPEN-DOC 27938

    OLIVEIRA, A.P.; RODAS, A.C.D.; DERNOWSEK, J.A.; QUEIROZ, A.; SANTOS, F.A. ; RICCARDI, C.S.. Formulações de biotintas à base de alginato contendo suspensão de células e esferóides, considerando parâmetros otimizados no fatiamento. In: WORKSHOP DE BIOMATERIAIS, ENGENHARIA DE TECIDOS E ORGÃOS ARTIFICIAIS, 6th, October 29-31, 2019, São Paulo, SP. Abstract... São Paulo, SP, 2019. p. 424-424.

    Abstract: A biotecnologia está ligada a várias ciências, porém, nos últimos anos, devido ao aumento da expectativa de vida da população, diversas abordagens foram destacadas como alternativa para minimizar os problemas decorrentes da idade. Nesse contexto, a engenharia de tecidos emerge uma ciência que visa projetar e ou sintetizar tecidos biocompatíveis capazes de favorecer a regeneração, melhorando aspectos da qualidade de vida da população. Uma das ferramentas mais usadas na engenharia de tecidos é a bioimpressão 3D, que envolve vários parâmetros: modelagem 3D, estruturação, maturação e análise. Vale ressaltar que o bioink consiste em formulações de célula esférica (esferóide) / agregado celular, que também podem conter moléculas ativas e biomateriais. No presente trabalho, foi realizado uma comparação entre diferentes biotintas à base de alginato, considerando uma formulação contendo suspensão celular e outra esferóides. Utilizaram-se fibroblastos de camundongo da cepa 3T3. No entanto, para a produção de esferóides, foi utilizada a técnica de Hidrogéis não Adesivo micromoldados, considerando o hidrogel de agarose. Os parâmetros utilizados no processo de bioimpressão foram otimizados usando o software Simplify 3D®. As análises dos construtos obtidos nas duas formulações dos biótipos foram realizadas por meio de Microscopia de Fluorescência, sendo possível analisar aspectos do diâmetro do filamento, dispersão celular e proliferação celular. Em relação ao diâmetro do filamento, a formulação contendo apenas a suspensão celular resultou em diâmetros mais uniformes. Em relação à dispersão celular, ambas as formulações apresentaram resultados satisfatórios, resultando em uma distribuição homogênea em todo o filamento e os resultados sobre a proliferação celular foram promissores. A bioimpressão não é um processo trivial e envolve vários parâmetros e processos; no entanto, foi possível obter resultados interessantes usando uma bioimpressora de baixo custo.

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  • IPEN-DOC 27943

    RODRIGUES, BRUNO L.; MAISTRO, CARLOS B.; FLOSI, ADRIANA A.; BERTOTTI, VICTOR A.; YORIYAZ, HELIO ; NUNES, MAIRA G. . Impacto dosimétrico de curvas CT-to-ED em irradiações de próteses e heterogeneidades de alto número atômico. In: CONGRESSO BRASILEIRO DE FÍSICA MÉDICA, 24., 21-24 de agosto, 2019, Santos, SP. Resumo expandido... São Paulo, SP: Associação Brasileira de Física Médica, 2019.

    Abstract: A presença de próteses em radioterapia normalmente está associada a limitações no planejamento e a imprecisão no cálculo de dose. Embora existam algoritmos precisos de correção de heterogeneidade, a principal dificuldade está no estabelecimento de curvas de correção CT-to-ED para altos valores de HU. A maioria dos tomógrafos trabalha em 12 bits, saturando em torno de 3070 HU, no entanto já existem equipamentos de 16 bits que não saturam na presença de materiais de alto número atômico (Z). O objetivo deste trabalho foi avaliar, em irradiações de heterogeneidades de alto Z, o ganho dosimétrico quando são utilizadas curvas de correção que incluem altos valores de HU. Os resultados indicaram uma dependência significativa das curvas com o tomógrafo avaliado, impactando diretamente na correção de heterogeneidades e causando desvios de até 11,3% em termos de atenuação.

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  • IPEN-DOC 27942

    MELETTI, AMANDA F.; BARSANELLI, CRISTIANE; RIBEIRO, VICTOR A.B.; YORIYAZ, HELIO ; SHORTO, JULIAN M.B. ; SIQUEIRA, PAULO T.D. ; NUNES, MAIRA G. . Levantamento da curva CT-TO-ED para CBCT. In: CONGRESSO BRASILEIRO DE FÍSICA MÉDICA, 24., 21-24 de agosto, 2019, Santos, SP. Resumo expandido... São Paulo, SP: Associação Brasileira de Física Médica, 2019.

    Abstract: A fim de se aproveitar a Tomografia de Feixe Cônico (CBCT) utilizada em técnicas de IGRT para estimar a dose entregue aos pacientes, foi levantada a curva CT-to-ED do sistema kV-CBCT da Elekta-XVI por meio do CatPhan® – objeto simulador com densidades conhecidas. Foram verificadas diferenças de até 36,7% nos valores de HUs obtidos com diferentes parâmetros de aquisição da CBCT, tornando-se essencial o estabelecimento de protocolos específicos de imageamento em cada Instituição. Apesar de o método até aqui empregado ter sido validado com desvios percentuais menores que 0,23%, diferenças ainda maiores foram verificadas entre as curvas da CT de referência e as da CBCT, o que torna indispensável estudar estratégias de correção que viabilizem a sua implementação na clínica.

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  • IPEN-DOC 27941

    BRANCO, I.S.L. ; ANTUNES, P.C.G. ; SIQUEIRA, P.T.D. ; SHORTO, J.M.B. ; YORIYAZ, H. . Estudo dos efeitos de composição e densidade de materiais tecido equivalentes na distribuição de dose longitudinal em protonterapia / Study of the composition and density effects of tissue equivalent materials on the longitudinal dose distribution in proton therapy. In: CONGRESSO BRASILEIRO DE FÍSICA MÉDICA, 24., 21-24 de agosto, 2019, Santos, SP. Anais... São Paulo, SP: Associação Brasileira de Física Médica, 2019. p. 1-6.

    Abstract: A eficiência de procedimentos radioterápicos depende do equilíbrio entre o fornecimento de altas doses conformadas ao volume tumoral e a restrição das doses recebidas pelos tecidos e órgãos saudáveis circundantes. Sendo uma modalidade de radioterapia, a protonterapia destaca-se neste cenário por possuir vantagens dosimétricas, que, quando combinadas com avanços tecnológicos, permitem que um grande potencial na conformidade da distribuição de dose. Este trabalho visa contribuir em um estudo dosimétrico, especificamente considerando os efeitos da heterogeneidade devido à presença de materiais tecido equivalentes com diferentes densidades e composições químicas, de modo a analisar qual destes parâmetros exerce maior influência na distribuição de dose longitudinal. A metodologia desenvolvida neste trabalho foi baseada em simulações de Monte Carlo com o código GEANT4 (através da interface TOPAS). Os objetos simuladores cilíndricos representados foram compostos inteiramente por diversos materiais tecido-equivalentes. Três grupos de estudo guiaram as simulações, o primeiro manteve a composição e densidade originais dos materiais, ao seguinte foi atribuída a todos os materiais heterogêneos a mesma densidade da água, mas mantiveram-se suas composições químicas originais; e por fim, foram realizadas simulações com as densidades originais dos materiais heterogêneos e composição química da água para todos os casos. Através da análise da distribuição de dose longitudinal variando com a profundidade, foi possível observar o comportamento da influência dos parâmetros de composição e densidade no alcance do feixe (d90) para os diferentes materiais e energias analisados. O estudo mostrou que, o efeito que a densidade dos materiais tecido equivalentes exerce sobre a deposição de dose é mais expressivo que o efeito de sua composição. A maior exatidão no range de tratamento permite evitar uma sub ou sobre dosagem da área irradiada. Esta é uma das diversas linhas de pesquisa que contribuem para a diminuição das incertezas em protonterapia.

    Palavras-Chave: radiotherapy; proton beams; radiation dose distributions; tissue-equivalent materials; monte carlo method; heterogeneous effects

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  • IPEN-DOC 27940

    MAZER, AMANDA C. ; SHORTO, JULIAN M.B. ; SIQUEIRA, PAULO T.D. ; NAKANDAKARI, MARCOS V.N.; RIBEIRO, VICTOR A.B.; YORIYAZ, HELIO . Análise da sensibilidade do ArcCHECK® / ArcCHECK® sensitivity analysis. In: CONGRESSO BRASILEIRO DE FÍSICA MÉDICA, 24., 21-24 de agosto, 2019, Santos, SP. Anais... São Paulo, SP: Associação Brasileira de Física Médica, 2019. p. 1-5.

    Abstract: Este artigo apresenta uma análise da sensibilidade do sistema dosimétrico ArcCHECK, através de comparações entre medidas experimentais envolvendo alguns tipos de deslocamentos mecânicos e medidas de uma referência fixa. O ArcCHECK é um sistema que contém 1386 diodos dispostos de forma helicoidal e que permite realizar medições para Controle de Qualidade de técnicas de radioterapia mais modernas e complexas. Foram feitas algumas medidas iniciais de repetibilidade e de linearidade e, em sequência, análises da capacidade do dispositivo em identificar erros de deslocamentos em diferentes direções, bem como a visualização de efeitos da resolução dos diodos. Foram encontradas diferenças consideráveis nos valores de dose entre deslocamentos pequenos e a referência. Também foram observadas deformações nas curvas de isodose para determinados ângulos de irradiação do sistema. O ArcCHECK foi considerado bastante sensível, dada a metodologia de análise, porém deve ser utilizado com cautela quando posicionado para realizar Controle de Qualidade.

    Palavras-Chave: dosimetry; equipment; irradiation; isodose curves; quality assurance; radiation dose distributions; radiotherapy

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  • IPEN-DOC 27939

    AGODI, C.; CAPPUZZELLO, F.; ACOSTA, L.; AMADOR-VALENZUELA, P.; AUERBACH, N.; BAREA, J.; BELLONE, J.I.; BELMONT, D.; BIJKER, R.; BONANNO, D.; BORELLO-LEWIN, T.; BOZTOSUN, I.; BRANCHINA, V.; BRASOLIN, S.; BRISCHETTO, G.; BRUNASSO, O.; BURRELLO, S.; CALABRESE, S.; CALABRETTA, L.; CALVO, D.; CAPIROSSI, V.; CARBONE, D.; CAVALLARO, M.; CHEN, R.; CIRALDO, I.; CHAVEZ LOMELI, E.R.; COLONNA, M.; D’AGOSTINO, G.; DJAPO, H.; DE GERONIMO, G.; DELAUNAY, F.; DESHMUKH, N.; DE FARIA, P.N.; ESPEJEL, R.; FERRARESI, C.; FERREIRA, J.L.; FERRETTI, J.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; FLORES, A.; FOTI, A.; GALLO, G.; GARCIA-TECOCOATZI, H.; GONGORA, B.; HACISALIHOGLU, A.; HAZAR, S.; HUERTA, A.; KOTILA, J.; KUCUK, Y.; IAZZI, F.; LANZALONE, G.; LA VIA, F.; LAY, J.A.; LENSKE, H.; LINARES, R.; LONGHITANO, F.; LO PRESTI, D.; LUBIAN, J.; MA, J.; MARIN-LAMBARRI, D.; MARTINEZ, S.; MAS, J.; MEDINA, N.H.; MENDES, D.R.; MEREU, P.; MORALLES, M. ; OLIVEIRA, J.R.B.; ORDOÑEZ, C.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PIETRALLA, N.; PINNA, F.; REITO, S.; REZA, G.; RIES, P.; RIFUGGIATO, D.; RODRIGUES, M.R.D.; RUSSO, A.D.; RUSSO, G.; SANDOVAL, S.; SANTOPINTO, E.; SANTOS, R.B.B.; SGOUROS, O.; SILVEIRA, M.A.G. da; SOLAKCI, S.O.; SOULIOTIS, G.; SOUKERAS, V.; SPATAFORA, A.; TORRESI, D.; TUDISCO, S.; VSEVOLODOVNA, R.I.M.; VARGAS, H.; VEGA, G.; WANG, J.S.; WERNER, V.; YANG, Y.Y.; YILDIRIN, A.; ZAGATTO, V.A.B.. New experimental campaign of NUMEN project. In: MARUYAMA, REINA (Ed.) SYMMETRIES AND ORDER: ALGEBRAIC METHODS IN MANY BODY SYSTEMS, October 5-6, 2018, Connecticut, USA. Proceedings... Melville, NY, USA: AIP Publishing, 2019. p. 30001-1 - 30001-6. (AIP Conference Proceedings, 2150). DOI: 10.1063/1.5124590

    Abstract: The NUMEN main goal is the extraction from measured cross-sections of “data-driven” information on Nuclear Matrix Elements for all the systems candidate for 0νββ. The idea is to use as experimental tool Heavy Ions –Double Charge Exchange (HI-DCE) reactions. Crucial for the experimental challanges is the INFN Laboratori Nazionali del Sud (LNS) facility, made by the Superconducting Cyclotron (CS) and the MAGNEX magnetic spectrometer. The experimental measurements of HI-DCE reactions present a number of challenging aspects, since they are characterized by very low cross sections. Here it is reported the new experimental campaign of NUMEN Project.

    Palavras-Chave: matrix elements; nuclear matrix; double beta decay; charge exchange; heavy ions

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  • IPEN-DOC 27936

    SANTOS, F.A. ; OLIVEIRA, A.P.; QUEIROZ, A.; RODAS, A.C.D.; SILVA, J.V.L.; DERNOWSEK, J.A.. Optimization of alginate/pluronic-based hydrogel slicing parameters for complex structure in bioprinting. In: WORKSHOP DE BIOMATERIAIS, ENGENHARIA DE TECIDOS E ORGÃOS ARTIFICIAIS, 6th, October 29-31, 2019, São Paulo, SP. Abstract... São Paulo, SP, 2019. p. 340-340.

    Abstract: A bioimpressão 3D está em constante crescimento e inserida na biofabricação onde envolve vários parâmetros e processos. Uma das propriedades que precisamos é uma boa estruturação do construto bioimpresso. No entanto, a reologia dos hidrogéis compostos por biomateriais é um fator determinante para a construção estável das geometrias impressas. Estratégias de estruturação física (temperatura, luz, rigidez, tensão) e química (pH, adição de moléculas indutoras) podem ser utilizadas. Nesse trabalho utilizamos um hidrogel a base de Alginato e Pluronic127 onde houve uma estruturação envolvendo fenômenos químico com cloreto de cálcio e térmico durante o processo. Inicialmente foi realizado a formulação do hidrogel - alginato 8% e Pluronic 25% - e em seguida a parametrização do fatiamento da geometria, realizada no software Simplify3D. Após a fase de fatiamento da geometria 3D realizamos a impressão do modelo de nariz retirado do banco de dados Thingiverse, disponível no site thingiverse.com.O trabalho ainda está em andamento, mas já alcançamos resultados satisfatórios. No entanto, para alcançar uma formulação mais próxima do ideal, serão necessários mais estudos.

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  • IPEN-DOC 27935

    SANTOS, THIAGO O. ; CARMO, AMANDA P. ; GONÇALVES, PEDRO N. ; DAMATTO, SANDRA R. . Determination of the natural radionuclides 226Ra, 228Ra and 210Pb activity concentrations in the mineral waters from the cities of Monte Alegre do Sul and Socorro, SP. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 42-49.

    Abstract: The use of mineral water for medical treatment is widespread throughout the world, and several mineral water springs have considerable concentrations of natural radionuclides from the 238U and 232Th series. The estimate of probable adverse effects on human health that may occur because of the ingestion or inhalation of radioactive substances present in these waters is relevant in Radiological Protection. The objective of this study was to determine the activity concentrations of the radionuclides 226Ra, 228Ra and 210Pb in the mineral water springs of Monte Alegre do Sul and Socorro, cities of the Paulista Water Circuit, collected in the seasons of summer, autumn, winter and spring of 2018; these cities have several mineral water springs distributed in many parts of them. The activity concentrations for the mineral waters from Monte Alegre do Sul ranged for 226Ra from limit detection of 2.2 ± 0.2 mBq L-1 to 23.0 ± 0.2 mBq L-1 , from limit detection of 3.7 ± 0.1 mBq L-1 to 16.0 ± 0,8 mBq L-1 for 228Ra and for 210Pb from the limit detection of 4.9 ± 0.4 mBq L-1 to 58 ± 5 mBq L -1 ; for Socorro ranged from limit detection of 2.2 ± 0.2 mBq L-1 to 11.0 ± 0.9 mBq L-1 for 226Ra, from limit detection of 3.7 ± 0.1 mBq L-1 to 48 ± 3 mBq L-1 for 228Ra and for 210Pb from limit detection of 4.9 ± 0.4 mBq L-1 to 49 ± 4 mBq L -1 .

    Palavras-Chave: natural radioactivity; radium isotopes; radium 226; radium 228; lead 210; ecological concentration; drinking water; minerals

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  • IPEN-DOC 27934

    CARMO, AMANDA P. ; SANTOS, THIAGO O. ; DAMATTO, SANDRA R. ; ULRICH, JOÃO C. . Assessment of Ra-226, Ra-228, Pb-210 and Po-210 activity concentrations and inorganic chemistry composition of the mineral waters of Amparo, SP. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 28-41.

    Abstract: Significant concentrations of natural radionuclides dissolved can be found in mineral water springs, mainly radionuclides from the 238U and 232Th decay series that are used worldwide due to its therapeutic properties. The estimation of possible adverse effects on human health due to the ingestion or inhalation of radioactive substances present in these waters is a relevant factor in the context of Radiological Protection. The objective of this work was to evaluate the activity concentrations of the radionuclides 226Ra, 228Ra, 210Pb and 210Po in the mineral water springs of the city of Amparo in the seasons of summer, autumn, winter and spring of 2018 and the committed effective doses due to the consumption of these waters, and as well as, characterize its chemical composition. The city of Amparo has 11 springs distributed in many places of the city and belongs to the Paulista Water Circuit. The highest activity concentrations were obtained for the radionuclides 228Ra and 210Po and consequently the highest committed effective dose. Among the chemical elements analyzed, Al, Mn, and Pb presented the highest concentrations in all the mineral water springs.

    Palavras-Chave: chemical composition; dose commitments; electric conductivity; lead 210; mineral springs; natural radioactivity; ph value; polonium 210; radiation protection; radium 226; radium 228

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  • IPEN-DOC 27933

    LEVY, DENISE S. ; SORDI, GIAN M.A.A. ; RODRIGUES, DEMERVAL L. ; CARNEIRO, JANETE C.G.G. . Communication about occupational exposure: linking workers to high-quality information. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 18-27.

    Abstract: Brazil is the largest country of Latin America, with 8.5 million square kilometers divided into five regions with 3 time zones. In this large between-country distances, with plenty of radioactive facilities throughout the country, professional education and communication is a must and a challenge. This paper discusses a web-based project designed to provide effective communication about occupational exposure, linking geographically distant workers to high-quality reliable information. The web-based-project UNIPRORAD counts on concepts, definitions and theory about radiological protection based on both national and international standards, guidelines and recommendations. The content includes optimization, monitoring, potential exposure and communication on occupational risk agents in the workplace. Regarding potential exposures, it is essential to consider the concept of “risk” which, even among scientific community, seems to assume a great variety of meanings. Regarding risk agents in the workplace, it is necessary to discuss the identification and evaluation of the various risk agents (physical, chemical biological and ergonomic) addressing attention to their association to ionizing radiation. This article presentsthe authors' experience in the communication of radiological protection in Brazil, presenting global and specific issues on radiological protection, analyzing recommendations and discussing discrepancies among the several valid publications. It is our objective the dissemination of trustful updated communication, providing radioactive facilities relevant, accurate and understandable information. Finally, the article emphasizes the need to spread information wherever it is needed to inform as many people as possible, contributing to develop workers´ professional skills and to improve safety culture in workplace.

    Palavras-Chave: communications; educational tools; hazards; information dissemination; internet; occupational exposure; radiation protection; risk assessment; safety culture

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  • IPEN-DOC 27932

    BORGES, EDUARDO M. ; SABUNDJIAN, GAIANE . Small break loss of coolant accident of 200 cm² in cold leg of primary loop of Angra2 nuclear power reactor evaluation. Brazilian Journal of Radiation Sciences, v. 9, n. 2B, p. 1-16, 2021. DOI: 10.15392/bjrs.v9i2B.1274

    Abstract: The aim of this paper is evaluated the consequences to ANGRA 2 nuclear power reactor and to identify the flow regimes, the heat transfer modes, and the correlations used by RELAP5/MOD3.2.gama code in ANGRA 2 during the Small-Break Loss-of-Coolant Accident (SBLOCA) with a 200cm2 of rupture area in the cold leg of primary loop. The Chapter 15 of the Final Safety Analysis Report of ANGRA 2 (FSAR-A2) reports this specific kind of accident. The results from this work demonstrated the several flow regimes and heat transfer modes that can be present in the core of ANGRA 2 during the postulated accident. The results obtained for ANGRA 2 nuclear reactor core during the postulated accident were satisfactory when compared with the FSAR-A2. Additionally, the results showed the correct actuation of the ECCS guaranteeing the integrity of the reactor core.

    Palavras-Chave: cladding; reactor cores; voids; heat transfer; coolant circuits; sbloca; steady-state conditions; two-phase flow; eccs; reactor accident simulation

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  • IPEN-DOC 27931

    OLIVEIRA, ELLISON A. de ; OLIVEIRA, PATRICIA da S.P. de ; MATTAR NETO, MIGUEL ; MATURANA, MARCOS C.. Overview of seismic probabilistic safety assessment applied to a nuclear installation located in a low seismicity zone. Brazilian Journal of Radiation Sciences, v. 9, n. 2B, p. 1-19, 2021. DOI: 10.15392/bjrs.v9i2B.1560

    Abstract: Deterministic and probabilistic safety analysis methodologies have been developed and updated based on operational experience, investigation of past incidents or accidents, and analysis of postulated initiating events in nuclear plants in order to maintain the protection of workers, the public and the environment. The evaluation of accident sequences and the total radiological risk resulting from off-site releases are general objectives addressed by these methodologies. There are hazards that continually challenge the safety of a nuclear facility or its nearby area. In particular, seismic events represent a major contributor to the risk of a nuclear accident. Different levels of ground motion induced by earthquakes may be experienced by structures, systems and components (SSCs) of an installation. In this context, a seismic hazard analysis, seismic demand analysis and seismic fragility analysis must be carried out in order to characterize the local seismic hazard and seismic demands on SSCs, allowing an adequate seismic classification of SSCs, even for installations located in sites with low seismicity. In this article, a general description of the Seismic Probabilistic Safety Assessment (Seismic PSA) methodology is presented, emphasizing the supporting studies. This methodology shall be applied to an experimental nuclear installation containing a PWR reactor designed for naval propulsion to be installed in a low seismicity zone in Brazil.

    Palavras-Chave: safety analisys; nuclear facilities; risk assessment; seismicity; earthquakes; hazards; probabilistic estimation

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  • IPEN-DOC 27930

    STEFANI, GIOVANNI L. de ; GENEZINI, FREDERICO A. ; SANTOS, THIAGO A. dos ; MOREIRA, JOAO M. de L.. Parametric study for enhancing the radioisotope production in the IEA-R1 research reactor. Brazilian Journal of Radiation Sciences, v. 9, n. 2B, p. 1-20, 2021. DOI: 10.15392/bjrs.v9i2B.1516

    Abstract: In this work a parametric study was carried to increase the production of radioisotopes in the IEA-R1 research reactor. The changes proposed to implement in the IEA-R1 reactor core were the substitution of graphite reflectors by beryllium reflectors, the removal of 4 fuel elements to reduce the core size and make available 4 additional locations to be occupied by radioisotope irradiation devices. The key variable analyzed is the thermal neutron flux in the irradiation devices. The proposed configuration with 20 fuel elements in an approximately cylindrical geometry provided higher average neutron flux (average increment of 12.9 %) allowing higher radioisotope production capability. In addition, it provided 4 more positions to install irradiation devices which allow a larger number of simultaneous irradiations practically doubling the capacity of radioisotope production in the IEA-R1 reactor. The insertion of Be reflector elements in the core has to be studied carefully since it tends to promote strong neutron flux redistribution in the core. A verification of design and safety parameters of the proposed core was carried out. The annual fuel consumption will increase about 17 % and more storage space for spent fuel will be required.

    Palavras-Chave: radioisotopes; fuel elements; beryllium; delayed neutrons; isotope production; neutron flux; spent fuels; thermal neutrons

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  • IPEN-DOC 27929

    VIEIRA NETO, ANTONIO S. ; OLIVA, AMAURY M. ; OLIVEIRA, PATRICIA da S.P. de ; HUNOLD, MARCOS C. ; SAUER, MARIA E.L.J. ; ANDREA, VINICIUS . Knowledge base about risk and safety of nuclear facilities to support analysts and decision-makers. Brazilian Journal of Radiation Sciences, v. 9, n. 2B, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i2B.1501

    Abstract: Epistemic uncertainty (related to lack of knowledge), often found in the documentation of nuclear facility engineering projects, can affect the decision-making process of managers and analysts on safety and risk issues. This article conceptualizes the nature of the major uncertainties involved in engineering projects. It describes a knowledge base developed to gather data and information related to an Open-Pool Light-water Research Reactor (OPLRR) project and whose purpose is to assist professionals who work in nuclear facilities. To reduce the epistemic uncertainties that may arise in the project, the OPLRR knowledge base is designed with a set of information that allows identifying and facilitating the forwarding of solutions to address inconsistencies and/or pending issues that may exist in the project. In this sense, the information and the documents related to the project are organized in a graphical and hierarchical architecture, allowing the knowledge base users to quickly and easily obtain information regarding the systems, processes, equipment, and components of the project. Besides that, a set of documents containing descriptions, reliability data, and some other information about the systems and components are specially created to the knowledge base, and it is crucial to reduce epistemic uncertainties once it raises the issues and the inconsistencies of the project, as well as it clarifies the interrelations between the systems, the functioning of the equipment, their failures modes and the consequences of their failures, and some other data, which are not originally contained in the documents of the project.

    Palavras-Chave: knowledge base; information dissemination; data acquisition systems; decision making; failure mode analysis; pool type reactors

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  • IPEN-DOC 27928

    FREITAS NETO, LUIZ G. de ; FREIRE, LUCIANO O. ; SANTOS, ADIMIR dos ; ANDRADE, DELVONEI A. de . Potential advantages of molten salt reactor for merchant ship propulsion. Brazilian Journal of Radiation Sciences, v. 9, n. 2B, p. 1-18, 2021. DOI: 10.15392/bjrs.v9i2B.1466

    Abstract: Operating costs of merchant ships, related to fuel costs, has led the naval industry to search alternatives to the current technologies of propulsion power. A possibility is to employ nuclear reactors like the Russian KLT-40S, which is a pressurized water reactor (PWR) and has experience on civilian surface vessels. However, space and weight are critical factors in a nuclear propulsion project, in addition to operational safety and costs. This work aims at comparing molten salt reactors (MSR) with PWR for merchant ship propulsion. The present study develops a qualitative analysis on weight, volume, overnight costs, fuel costs and nuclear safety. This work compares the architecture and operational conditions of these two types of reactors. The result is that MSR may produce lower amounts of high-activity nuclear tailings and, if it adopts the U233-thorium cycle, it may have lower risks of proliferating nuclear weapons. Besides proliferation issues, this 4th generation reactor may have lower weight, occupy less space, and achieve the same levels of safety with less investment. Thus, molten salt regenerative reactors using the U233-thorium cycle are potential candidates for use in ship propulsion.

    Palavras-Chave: ship propulsion reactors; nuclear merchant ships; comparative evaluations; molten salt reactors; nuclear fuels; radiation protection; reactor safety

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  • IPEN-DOC 27927

    FREIRE, LUCIANO O. ; ANDRADE, DELVONEI A. de . Entering new markets: nuclear industry challenges. Brazilian Journal of Radiation Sciences, v. 9, n. 2B, p. 1-15, 2021. DOI: 10.15392/bjrs.v9i2B.1463

    Abstract: Nuclear ship propulsion and isolated islands energy supply are unexplored markets for nuclear vendors. Carbon taxes and fuel regulations may make fossil fuels more expensive. Such markets pay more for energy because of organization and transport costs and use of small machines, which are less efficient than grid generators. The goal of this work is to find the measures the nuclear industry needs to take to get into new potential markets. This work shows the different actors and their interests and points the natural or physical constraints they face. Considering interests and constraints, this work named the most probable market niches where nuclear power may beat other power sources. After considering natural constraints, this paper analyses human-generated constraints and presents a way on how to mitigate or solve them. This study shows that nuclear industry needs to take technical, administrative, and political measures before nuclear power arrives to a wider market. This work is based on literature review and qualitative analysis and cannot point precise thresholds where nuclear power should be competitive. Future work will consist of statistical analysis to find precise thresholds to help in the decision-making process.

    Palavras-Chave: nuclear ships; ; nuclear industry; propulsion reactors; nuclear power; market; political aspects; energy sources

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  • IPEN-DOC 27926

    GIOVEDI, C.; ABE, A. ; MUNIZ, R.O.R. ; GOMES, D.S. ; SILVA, A.T. ; MARTINS, M.R.. Modification of fuel performance code to evaluate iron-based alloy behavior under LOCA scenario. Brazilian Journal of Radiation Sciences, v. 9, n. 2A, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i2A.393

    Abstract: Accident tolerant fuels (ATF) has been studied since the Fukushima Daiichi accident in the research efforts to develop new materials which under accident scenarios could maintain the fuel rod integrity for a longer period compared to the cladding and fuel system usually utilized in Pressurized Water Reactors (PWR). The efforts have been focused on new materials applied as cladding, then iron-base alloys appear as a possible candidate. The aim of this paper is to implement modifications in FRAPCON and FRAPTRAN fuel performance codes to evaluate the behavior of iron-based alloys under Loss-of-Coolant Accident (LOCA) scenario. For this, initially the properties related to the thermal and mechanical behavior of iron-based alloys were obtained from the literature, appropriately adapted and introduced in the fuel performance code subroutines. The adopted approach was step by step modifications, where different versions of the code were created. The assessment of the implemented modification was carried out simulating an experiment available in the open literature (IFA-650.5) related to zirconium-based alloy fuel rods submitted to LOCA conditions. The obtained results for the iron-based alloy were compared to those obtained using the regular version of the fuel performance code for zircaloy-4. The obtained results have shown that the most important properties to be changed are those from the subroutines related to the mechanical properties of the cladding. The results obtained have shown that the burst is observed at a longer time for fuel rods with iron-based alloy, indicating the potentiality of this material to be used as cladding with ATF purposes.

    Palavras-Chave: ; stainless steel-348; accident-tolerant nuclear fuels; fuel rods; iron alloys; computerized simulation; f codes; loss of coolant; pwr type reactors

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  • IPEN-DOC 27925

    SAKAI, M.C.C.B. ; RIELLA, H.G. ; CARVALHO, E.F.U. . Quantification of effluents in the production of nuclear fuel. Brazilian Journal of Radiation Sciences, v. 9, n. 2A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i2A.620

    Abstract: The Brazil with the purpose of becoming self-sufficient in the production of radioisotopes and radioactive sources used in nuclear medicine, agriculture and the environment developed the project of a multipurpose reactor of 30 megawatts of power to attend the national demand. In the Nuclear and Energy Research Institute (IPEN), Nuclear Fuel Center (CCN) is responsible for the manufacture of fuel for the reactor IEA-R1 and, possibly, the multipurpose reactor fuels. In order to meet the demand for the reactors was designed a new manufacturing plant with a maximum capacity of 60 fuel elements, which is 10 nowadays. The increase in production as a consequence will increase the volume of effluents generated. The current concern with the environment it is necessary to draw up a management plan to make the process sustainable, which will result in environmental, economic and social benefits. The fuel production process generates various types of effluent containing uranium or not – being solid, gaseous and liquid with different physical and chemical characteristics. The aim of this work is to follow the process of nuclear fuel production and to identify, quantify and characterize the effluents, especially liquids, to subsequently draw up a management plan and eventually dispose of responsibly in the environment.

    Palavras-Chave: radioactive waste management; radioactive effluents; environmental impacts; liquid wastes; nuclear fuels; production

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  • IPEN-DOC 27924

    DAMASCENO, M.O. ; MARQUES, F.A. da S. ; DIAS, R.R. ; SANTOS, J.L. ; FORBICINI, C.A.L.G.O. . Study of new routes for purification of fission 99Mo. Brazilian Journal of Radiation Sciences, v. 9, n. 2, p. 1-16, 2021. DOI: 10.15392/bjrs.v9i2.1623

    Abstract: 99mTc is the most used medical radioisotope in the world, especially for diagnosis procedures. It is originated in the radioactive decay of 99Mo, which in turn is one of the fission products of the uranium irradiation that occurs in nuclear reactors. The chemical processing of 99Mo might be lined up in several steps according to the characteristics of the targets or the local requirements in order to separate it from other fission products. In this work, two routes of 99Mo purification, MR1 and MR2, were purposed as an alternative method to be set up in the Brazilian Multipurpose Reactor project. The MR1 route consisted by three consecutives chromatographic columns packed with strong anionic resin, Chelating resin, and aluminum oxide, respectively. The MR2 route was arranged in two chromatographic columns and a sublimation oven. The final yield for the MR1 was 84.4% and the overall time process was about 7 hours, performing the highest final 99Mo recovery efficiency, high decontamination degree and a shorter process time compared to the MR2.

    Palavras-Chave: fission; molybdenum 99; purification; routing; extraction columns

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  • IPEN-DOC 27923

    TEIXEIRA, B.S. ; CHIERENTIN, G.S. ; DEL MASTRO, N.L. . Impact of electron beam irradiation in potato starch films containing hibiscus aqueous extract. Brazilian Journal of Radiation Sciences, v. 9, n. 2, p. 1-15, 2021. DOI: 10.15392/bjrs.v9i2.1704

    Abstract: The development of starch films containing natural antioxidants is one alternative of active packaging. Starch is a well studied natural biopolymer that can be used for the development of biodegradable films because it presents a low cost, is easy to obtain and presents good ability to form films. Hibiscus sabdariffa, commonly known as roselle or red sorrel, is an annual her baceous sub shrub that contains many types of biocompounds, including organic and phenolic acids. The aim of the present work was to determine the influence of electron beam irradiation on potato starch film containing hibiscus extract. The aqueous hibiscu s solution was prepared by boiling for 3 min 1% w/ml dehydrated hibiscus flowers in 500 ml deionized water. The film forming solution was prepared by casting ( potato starch, 3% glycerol as plasticizer and the hibiscus solution) and irradiated in a 1.5 M eV electron beam accelerator Dynamitron II (Radiation Dynamics Inc.), with doses of 0, 20, 40 and 60 kGy. After drying some mechanical properties were measured. The tensile strength of the control films and the irradiated ones was established. There were n o significant differences among them. Hibiscus antioxidants were able to prevent the starch radiation degradation process caused by radiation induced free radicals.

    Palavras-Chave: antioxidants; electron beams; films; polymers; potatoes; solubility; starch; tensile properties; thickness

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  • IPEN-DOC 27922

    OLIVEIRA, L.P. ; SOUZA, A.P.S. ; YOKAICHIYA, F.; GENEZINI, F.A. ; FRANCO, M.K.K.D. . Study on s-shaped guide using mcstas software. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-8, 2021. DOI: 10.15392/bjrs.v9i1A.1549

    Abstract: Monte Carlo simulations are performed for a vertical S-shaped neutron guide for the cold neutron sources of the FRM-II, HZB and PSI reactors through the McStas software. The aim of our study is investigate a relation between the cutoff in the cold neutron spectrum and the sources. Results for the neutron flux at the sample position are presented for different supermirrors with m = 1, 2 and 3. The vertical S-shaped neutron guides additionally provide a vertical displacement between beam hole and sample position, which can facilitate the implementation and manipulation of sample environments.

    Palavras-Chave: cold neutrons; frm-ii reactor; m codes; monte carlo method; neutron flux; neutron sources; small angle scattering

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  • IPEN-DOC 27921

    SUZART, K.F. ; VELO, A.F. ; HAMADA, M.M. ; PEREIRA, M.C.C. ; MESQUITA, C.H. . Characterization of the CsI(Tl) crystalline scintillating detector produced at IPEN. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-13, 2021. DOI: 10.15392/bjrs.v9i1A.1586

    Abstract: Cesium iodide crystal activated with thallium (CsI(Tl)) is used as radiation sensor because of its favorable characteristics as scintillator, when excited by gamma radiation. This crystal has good mechanical strength and it is relatively little hygroscopic. In the present work, the CsI(Tl) crystal was grown in the Nuclear Energy Research Institute (IPEN/CNEN/SP) by Brigdman technique, in two different formats: (a) cylindric (∅ 20.1 mm x ↑ 11.9 mm) and (b) parallelepiped (12.3 mm x ↑ 19.5 mm). The scintillator spectrometry was studied through five gamma radiation sources: 99mTc (140 keV), 133Ba (355 keV) 22Na (511 keV) and 137Cs (662 keV). The crystals were coupled to a photomultiplier tube using 0.5 McStokes viscosity silicone grease as the optical interface. All electronics for signal measurements were developed at IPEN. Luminescence property of the CsI(Tl) crystal was excited by the radiation from a 137Cs source. The energy resolution of the crystalline detector was determined by the FWHM parameter, corresponding to the photopeak width at half of its height.

    Palavras-Chave: barium 133; cesium 137; sodium 22; technetium 99; thallium; iodides; crystals; luminescence; radiation detectors

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  • IPEN-DOC 27920

    AMADEU, R.A. ; BERNARDES, T.L.S. ; SANTOS, R.S. ; GARCIA, R.H.L. ; VELO, A.F. ; CAVALLARO, F.A.; MESQUITA, C.H. ; HAMADA, M.M. . Characterization of the petrology of the tar sandstone rock of the Paraná basin. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-17, 2021. DOI: 10.15392/bjrs.v9i1A.1585

    Abstract: In the state of São Paulo (Brazil), occurrences of tar sandstone are known in Botucatu, Angatuba, Pirambóia, Anhembi and Bofete municipalities. In the present work a sample of white tar sandstone was taken from Anhembi municipality, located at Km 168 of the Castelo Branco Highway. In the petroleum area, sandstones act as excellent hydrocarbon reservoirs, since they have specific characteristics, such as: high porosity and permeability. Porosity is a property of rocks, and it may be understood as the voids contained in the matrix (where fluids remain stored), while permeability is the ability of the rock to transmit these stored fluids. Due to these characteristics of sandstones, researchers have shown a growing interest in the study and characterization of this type of rock, which is a fundamental element of an oil system. In the present work, four characterization techniques were used in the Anhembi tar sandstone sample, namely: X-ray Diffraction (XRD), X-ray Fluorescence (XRF), Scanning Electron Microscope (SEM) and the third generation Industrial Computerized Tomography. Through these techniques, the chemical composition, grain morphology, crystalline structure phases and an image of a slice of the internal structure of the white tar sandstone sample were obtained.

    Palavras-Chave: petrology; sandstones; chemical composition; computerized tomography; crystal structure; tar

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

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

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

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

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

Exemplo:

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

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

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

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

✔ Ao efetuar a busca por um autor o RD apresentará uma relação de todos os trabalhos depositados no RD. No lado direito da tela são apresentados os coautores com o número de trabalhos produzidos em conjunto bem como os assuntos abordados e os respectivos anos de publicação agrupados.

✔ O RD disponibiliza um quadro estatístico de produtividade, onde é possível visualizar o número dos trabalhos agrupados por tipo de coleção, a medida que estão sendo depositados no RD.

✔ Na página inicial nas referências são sinalizados todos os autores IPEN, ao clicar nesse símbolo será aberta uma nova página correspondente à aquele autor – trata-se da página do pesquisador.

✔ Na página do pesquisador, é possível verificar, as variações do nome, a relação de todos os trabalhos com texto completo bem como um quadro resumo numérico; há links para o Currículo Lattes e o Google Acadêmico ( quando esse for informado).

ATENÇÃO!

ESTE TEXTO "AJUDA" ESTÁ SUJEITO A ATUALIZAÇÕES CONSTANTES, A MEDIDA QUE NOVAS FUNCIONALIDADES E RECURSOS DE BUSCA FOREM SENDO DESENVOLVIDOS PELAS EQUIPES DA BIBLIOTECA E DA INFORMÁTICA.

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

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

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.

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

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

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

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