Navegação por tipo de publicação "Artigo de periódico"

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  • IPEN-DOC 26393

    FERREIRA, EDUARDO G.A. ; MARUMO, JULIO T. ; FRANCO, MARGARETH K.K.D. ; YOKAICHIYA, FABIANO; VICENTE, ROBERTO . 10000 years cement: Can hydrated cement last as much as long-lived radionuclides?. Cement and Concrete Composites, v. 103, p. 339-352, 2019. DOI: 10.1016/j.cemconcomp.2019.05.016

    Abstract: This review is focused on the long-term performance of cementitious materials in a repository for radioactive waste. During the last few years, the disposal of disused sealed radioactive sources (DSRS) in a borehole type repository has been studied by many countries. The borehole concept is particularly useful to dispose of spent nuclear fuel and DSRS. In boreholes for DSRS, cementitious materials are intended to be used as structural material, immobilization matrix and as backfill. The understanding of the performance of these materials is essential to ensure the safety of the facilities during their required lifetime, from centuries to many thousands of years, depending on the initial activity and half-life of the waste. This review approaches the behavior of the cement from the hydration and hardening to the long-term processes that can affect its durability. Three main causes of failure of repository-engineered barriers are recognized: a) the formation of a preferential pathway for the migration of the contained radionuclides to the biosphere; b) loss of resistance and cohesion of the structural cementitious material; and c) the increase in the corrosion processes of the metallic components of the structures that affect the overall containment of the facility.

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  • IPEN-DOC 23152

    BERECZKI, ALLAN ; WETTER, NIKLAUS U. . 100W continuous linearly polarized, high beam quality output from standard side-pumped Nd:YAG laser modules. Optics and Laser Technology, v. 96, p. 271-275, 2017. DOI: 10.1016/j.optlastec.2017.05.020

    Abstract: Dynamically stable operation with joined stability zones of a linearly polarized resonator is shown for a laser containing two diode side-pumped Nd:YAG rods. The unpolarized resonator generated 115W of output. When polarized by a Brewster plate, it reached 100.5W of output power at a beam quality M2 < 2. Best measured beam quality was of 1.1 and 1.3 in the x and y directions respectively, with 76W of 95% polarized output. The output power achieved is, to our knowledge, the highest reported for continuous polarized, fundamental-mode lasers using standard side-pumped Nd:YAG modules.

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  • IPEN-DOC 17225

    HUDSON, D.; MAGI, E.; GOMES, L. ; JACKSON, S.D.. 1W diode-pumped tunable Hosup(3+) Prsup(3+)-doped fluoride glass fibre laser. Electronics Letters, v. 47, n. 17, p. 985-986, 2011.

    Palavras-Chave: diode-pumped solid state lasers; holmium; praseodymium; doped materials; fluorides; glass; optical fibers

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  • IPEN-DOC 08652

    HIRAMOTO, R.M.; GALISTEO JUNIOR, A.J.; NASCIMENTO, N. ; ANDRADE JUNIOR, H.F. . 200 Gy sterilised Toxoplasma gondii tachyzoites maintain metabolic functions and mammalian cell invasion, eliciting cellular immunity and cytokine response similar to natural infection in mice. Vaccine, v. 20, n. 16, p. 2072-2081, 2002.

    Palavras-Chave: parasitic diseases; parasites; protozoa; irradiation; gamma radiation; cobalt 60; morphological changes; metabolism; immunity; mice

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  • IPEN-DOC 26477

    SPATAFORA, A.; CAPPUZZELLO, F.; CARBONE, D.; CAVALLARO, M.; LAY, J.A.; ACOSTA, L.; AGODI, C.; BONANNO, D.; BONGIOVANNI, D.; BOZTOSUN, I.; BRISCHETTO, G.A.; BURRELLO, S.; CALABRESE, S.; CALVO, D.; LOMELI, E.R.C.; CIRALDO, I.; COLONNA, M.; DELAUNAY, F.; DESHMUKH, N.; FERREIRA, J.L.; FINOCCHIARO, P.; FISICHELLA, M.; FOTI, A.; GALLO, G.; HACISALIHOGLU, A.; IAZZI, F.; LANZALONE, G.; LENSKE, H.; LINARES, R.; PRESTI, D.L.; LUBIAN, J.; MORALLES, M. ; MUOIO, A.; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; REITO, S.; RUSSO, G.; SANTAGATI, G.; SGOUROS, O.; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; TORRESI, D.; TUDISCO, S.; YILDIRIM, A.; ZAGATTO, V.A.B.. 20Ne + 76Ge elastic and inelastic scattering at 306 MeV. Physical Review C, v. 100, n. 3, p. 034620-1 - 034620-8, 2019. DOI: 10.1103/PhysRevC.100.034620

    Abstract: Background: Double charge exchange (DCE) nuclear reactions have recently attracted much interest as tools to provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless double-β decay. In this framework, a good description of the reaction mechanism and a complete knowledge of the initial and final-state interactions are mandatory. Presently, not enough is known about the details of the optical potentials and nuclear response to isospin operators for many of the projectile-target systems proposed for future DCE studies. Among these, the 20Ne + 76Ge DCE reaction is particularly relevant due to its connection with 76Ge double-β decay. Purpose: We intend to characterize the initial-state interaction for the 20Ne + 76Ge reactions at 306 MeV bombarding energy and determine the optical potential and the role of the couplings between elastic channel and inelastic transitions to the first low-lying excited states. Methods: We determine the experimental elastic and inelastic scattering cross-section angular distributions, compare the theoretical predictions by adopting different models of optical potentials with the experimental data, and evaluate the coupling effect through the comparison of the distorted-wave Born approximation calculations with the coupled channels ones. Results: Optical models fail to describe the elastic angular distribution above the grazing angle (≈9.4◦). A correction in the geometry to effectively account for deformation of the involved nuclear systems improves the agreement up to about 14◦. Coupled channels effects are crucial to obtain good agreement at large angles in the elastic scattering cross section. Conclusions: The analysis of elastic and inelastic scattering data turned out to be a powerful tool to explore the initial and final-state interactions in heavy-ion nuclear reactions at high transferred momenta.

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  • IPEN-DOC 24704

    ARAGAO, LUIZ E.O.C.; ANDERSON, LIANA O.; FONSECA, MARISA G.; ROSAN, THAIS M.; VEDOVATO, LAURA B.; WAGNER, FABIEN H.; SILVA, CAMILA V.J.; SILVA JUNIOR, CELSO H.L.; ARAI, EGIDIO; AGUIAR, ANA P.; BARLOW, JOS; BERENGUER, ERIKA; DEETER, MERRITT N.; DOMINGUES, LUCAS G. ; GATTI, LUCIANA ; GLOOR, MANUEL; MALHI, YADVINDER; MARENGO, JOSE A.; MILLER, JOHN B.; PHILLIPS, OLIVER L.; SAATCHI, SASSAN. 21st Century drought-related fires counteract the decline of Amazon deforestation carbon emissions. Nature Communications, v. 9, n. 536, 2018. DOI: 10.1038/s41467-017-02771-y

    Abstract: Tropical carbon emissions are largely derived from direct forest clearing processes. Yet, emissions from drought-induced forest fires are, usually, not included in national-level carbon emission inventories. Here we examine Brazilian Amazon drought impacts on fire incidence and associated forest fire carbon emissions over the period 2003-2015. We show that despite a 76% decline in deforestation rates over the past 13 years, fire incidence increased by 36% during the 2015 drought compared to the preceding 12 years. The 2015 drought had the largest ever ratio of active fire counts to deforestation, with active fires occurring over an area of 799,293 km(2). Gross emissions from forest fires (989 +/- 504 Tg CO2 year(-1)) alone are more than half as great as those from old-growth forest deforestation during drought years. We conclude that carbon emission inventories intended for accounting and developing policies need to take account of substantial forest fire emissions not associated to the deforestation process.

    Palavras-Chave: carbon dioxide; deforestation; forests; monitoring; greenhouse gases; tropical regions; climates; droughts; fires; amazon river; brazil

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  • IPEN-DOC 17268

    OLIVEIRA, SONIA M.B. de; PESSENDA, LUIZ C.R.; FAVARO, DEBORAH I.T. ; BABINSKI, MARLY. A 2400-year record of trace metal loading in lake sediments of Lagoa Vermelha southeastern Brazil. Journal of South American Earth Sciences, v. 33, n. 1, p. 1-7, 2012.

    Palavras-Chave: brazil; lakes; sediments; metals; lead isotopes; isotope ratio; atmospheres; fallout; pollution

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  • IPEN-DOC 11810

    SAMAD, RICARDO E. ; BALDOCHI, SONIA L. ; NOGUEIRA, GESSE E.C. ; VIEIRA JUNIOR, NILSON D. . 30 W Cr:LiSrAlFsub(6) flashlamp-pumped pulsed laser. Optics Letters, v. 32, n. 1, p. 50-52, 2007.

    Palavras-Chave: chromium ions; lithium fluorides; strontium fluorides; aluminium fluorides; optical pumping; pumping; luminescence

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  • IPEN-DOC 19230

    VIANA, R.S.; AGASTHYA, G.A.; YORIYAZ, H. ; KAPADIA, A.J.. 3D element imaging using NSECT for the detection of renal cancer: a simulation study in MCNP. Physics in Medicine and Biology, v. 58, n. 17, p. 5867-5883, 2013.

    Palavras-Chave: kidneys; carcinomas; computerized tomography; three-dimensional calculations; neutron emission; stimulated emission; simulation; m codes

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  • IPEN-DOC 13733

    SANTOS, CARLOS A.X.; HAYAKAWA, MOTOZO; BRESSIANI, JOSE C. . 3Y-TZP/Sisub(2)Nsub(2)O composite obtained by pressureless sintering. Materials Science Forum, v. 591-593, p. 415-422, 2008.

    Palavras-Chave: zirconium oxides; composite materials; silicon nitrides; silicon carbides; sintering

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  • IPEN-DOC 11863

    GARCIA, R.H.L. ; USSUI, V. ; LIMA, N.B. ; LAZAR, D.R.R. . 3YTZP-Alsub(2)Osub(3) powders synthetized by the coprecipitation route. Materials Science Forum, v. 530-531, p. p. 677-682, 2006.

    Palavras-Chave: aluminium oxides; zirconium oxides; ceramics; hardness; powders; synthesis; coprecipitation; x-ray diffraction; scanning electron microscopy

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  • IPEN-DOC 13163

    SAMAD, R.E. ; NOGUEIRA, G.E.C. ; BALDOCHI, S.L. ; VIEIRA JUNIOR, NILSON D. . A 5 Hz flasglamp pumped Cr:LiSAF multipass amplifier for ultrashort pulses. Journal of Optics, A: Pure and Applied Optics, v. 10, p. 104010-1 - 104010-5, 2008.

    Palavras-Chave: diode-pumped solid state lasers; chromium; pulse amplifiers; thermal treatments

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  • IPEN-DOC 26392

    BENEDETTO, RAQUEL ; MASSICANO, ADRIANA V.F.; CRENSHAW, BRYANT K.; OLIVEIRA, RENATO; REIS, RUI M.; ARAUJO, ELAINE B. ; LAPI, SUZANNE E.. 89Zr-DFO-cetuximab as a molecular imaging agent to identify cetuximab resistance in head and neck squamous cell carcinoma. Cancer Biotherapy and Radiopharmaceuticals, v. 34, n. 5, p. 288-296, 2019. DOI: 10.1089/cbr.2018.2616

    Abstract: Background: Despite the improvement in clinical outcomes for head and neck squamous cell carcinoma (HNSCC) as the result of cetuximab, patients may present with or develop resistance that increases tumor recurrence rates and limits clinical efficacy. Therefore, identifying those patients who are or become resistant is essential to tailor the best therapeutic approach. Materials and Methods: Cetuximab was conjugated to p-NCS-Bz-DFO and labeled with 89Zr. The resistance model was developed by treating FaDu cells with cetuximab. Western blotting (WB) and specific binding assays were performed to evaluate epidermal growth factor receptor (EGFR) expression and 89Zr-DFO-cetuximab uptake in FaDu cetuximab-resistant (FCR) and FaDu cetuximab-sensitive (FCS) cells. Positron emission tomography imaging and biodistribution were conducted in NU/NU nude mice implanted with FCR or FCS cells. Results: Cetuximab was successfully radiolabeled with 89Zr (‡95%). Binding assays performed in FCR and FCS cells showed significantly lower 89Zr-DFO-cetuximab uptake in FCR ( p < 0.0001). WB suggests that the resistance mechanism is associated with EGFR downregulation ( p = 0.038). This result is in agreement with the low uptake of 89Zr-DFO-cetuximab in FCR cells. Tumor uptake of 89Zr-DFO-cetuximab in FCR was significantly lower than FCS tumors ( p = 0.0340). Conclusions: In this work, the authors showed that 89Zr-DFO-cetuximab is suitable for identification of EGFR downregulation in vitro and in vivo. This radiopharmaceutical may be useful for monitoring resistance in HNSCC patients during cetuximab therapy.

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  • IPEN-DOC 09367

    OLIVEIRA, L.M.; RODRIGUES, L.N. . A-type apatite/ESR dosimetry in the therapy dose level to photons. Revista Brasileira de Pesquisa e Desenvolvimento, v. 4, n. 3, Parte 1, p. 950-953, 2002.

    Palavras-Chave: dosimetry; dosemeters; apatites; calcium phosphates; electron spin resonance; cobalt 60; radiotherapy

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  • IPEN-DOC 13832

    MIYAKAWA, W.; DAMIAO, A.J.; SALGADO, E.G.C.; RIVA, R.; ZEZELL, D.M. . Ablation of human enamel using the Cu-HBr laser: a pilot-study. Revista Brasileira de Aplicações de Vácuo, v. 27, n. 1, p. 15-17, 2008.

    Palavras-Chave: dental enamel; laser ablation; copper; oral cavity; diagrams

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  • IPEN-DOC 23168

    GALANTE, RAQUEL; REDIGUIERI, CAROLINA F.; KIKUCHI, IRENE S.; VASQUEZ, PABLO A.S. ; COLACO, ROGERIO; SERRO, ANA P.; PINTO, TEREZINHA J.A.. About the sterilization of chitosan hydrogel nanoparticles. Plos One, v. 11, n. 12, 2016. DOI: 10.1371/journal.pone.0168862

    Abstract: In the last years, nanostructured biomaterials have raised a great interest as platforms for delivery of drugs, genes, imaging agents and for tissue engineering applications. In particular, hydrogel nanoparticles (HNP) associate the distinctive features of hydrogels (high water uptake capacity, biocompatibility) with the advantages of being possible to tailor its physicochemical properties at nano-scale to increase solubility, immunocompatibility and cellular uptake. In order to be safe, HNP for biomedical applications, such as injectable or ophthalmic formulations, must be sterile. Literature is very scarce with respect to sterilization effects on nanostructured systems, and even more in what concerns HNP. This work aims to evaluate the effect and effectiveness of different sterilization methods on chitosan (CS) hydrogel nanoparticles. In addition to conventional methods (steam autoclave and gamma irradiation), a recent ozone-based method of sterilization was also tested. A model chitosan-tripolyphosphate (TPP) hydrogel nanoparticles (CS-HNP), with a broad spectrum of possible applications was produced and sterilized in the absence and in the presence of protective sugars (glucose and mannitol). Properties like size, zeta potential, absorbance, morphology, chemical structure and cytotoxicity were evaluated. It was found that the CS-HNP degrade by autoclaving and that sugars have no protective effect. Concerning gamma irradiation, the formation of agglomerates was observed, compromising the suspension stability. However, the nanoparticles resistance increases considerably in the presence of the sugars. Ozone sterilization did not lead to significant physical adverse effects, however, slight toxicity signs were observed, contrarily to gamma irradiation where no detectable changes on cells were found. Ozonation in the presence of sugars avoided cytotoxicity. Nevertheless, some chemical alterations were observed in the nanoparticles.

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  • IPEN-DOC 07146

    CAMARGO, I.M.C. ; SAIKI, M. ; VASCONCELLOS, M.B.A. ; AVILA, D.M. . Abrasiveness evaluation of silica and calcium carbonate used in the production of dentifrices. Journal Cosmetic Science, v. 52, p. 163-167, 2001.

    Palavras-Chave: dentifrice; teeth; dentin; silicon oxides; calcium carbonates; abrasion; abrasives; wear; radiometric analysis; phosphorus 32; particle size

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  • IPEN-DOC 16512

    DOGRA, R.; CORDEIRO, M.R.; CARBONARI, A.W. ; SAXENA, R.N. ; COSTA, M.S.. Absence of room temperature ferromagnetism in transition metal doped ZnO nanocrystalline powders from PAC spectroscopy. Hyperfine Interactions, v. 197, p. 77-81, 2010.

    Palavras-Chave: zinc oxides; perturbed angular correlation; magnetism; sol-gel process

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  • IPEN-DOC 07569

    ATTIE, M.R.P.; KOSKINAS, M.F. ; DIAS, M.S. ; FONSECA, K.A. . Absolute disintegration rate measurements of Ga-67. Applied Radiation and Isotopes, v. 49, n. 9/11, p. 1175-1177, 1998.

    Palavras-Chave: gallium 67; standardization; decay; coincidence methods; proportional counters; nai detectors; high-purity ge detectors; gamma spectroscopy

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  • IPEN-DOC 11139

    MAIDANA, N.L.; TAKEDA, M.N.; DIAS, M.S. ; KOSKINAS, M.F. ; VANIN, V.R.. Absolute measurement of sup(242g)Am sources activities in the sup(241)Am(n, gamma)cross-section determination-improvement by simulation. Nuclear Instruments and Methods in Physics Research, v. 553, n. 3, Section A, p. 559-568, 2005.

    Palavras-Chave: americium 241; americium 242; proportional counters; activity levels; efficiency; tracer techniques; cobalt 60; beta detection; simulation; monte carlo method

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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.