Navegação Livros - Capítulos por Tipo de acesso "closedAccess"

Classificar por: Ordenar: Resultados:

  • IPEN-DOC 25635

    MUNHOZ JUNIOR, ANTONIO H.; PACHECO, CAROLINE V.; MELO, HENRIQUE T.T.S.; PERES, RENATO M.; SILVA, LEONARDO G. de A. e ; MIRANDA, LEILA F. de; ROMERO FILHO, MARCOS. Characterization of a composite of high-impact polystyrene, pseudoboehmite and graphene oxide. In: LI, BOWEN (Ed.); LI, JIAN (Ed.); IKHMAYIES, SHADIA (Ed.); ZHANG, MINGMING (Ed.); KALAY, YUNUS E. (Ed.); CARPENTER, JOHN S. (Ed.); HWANG, JIANN-YANG (Ed.); MONTEIRO, SERGIO N. (Ed.); BAI, CHENGUANG (Ed.); ESCOBEDO-DIAZ, JUAN P. (Ed.); SPENA, PASQUALE R. (Ed.); GOSWAMI, RAMASIS (Ed.). Characterization of Minerals, Metals, and Materials. Cham, CZ, Switzerland: Springer Nature Switzerland AG, 2019. p. 511-522, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-030-05749-7_51

    Abstract: The application of a composite material of pseudoboehmite, polystyrene and graphene oxide was studied. The present work is the synthesis and characterization of high-impact polystyrene (HIPS) nanocomposite, with pseudoboehmite (PSB) and graphene oxide. Pseudoboehmite particles with nanometric dimensions were obtained by sol-gel process. The composites were characterized by mechanical tests (tensile strength, flexural strength, Izod Impact, Shore D Hardness), thermal (Flow index, temperature of thermal deflection under load-HDT, Vicat softening temperature, differential tests thermal analyses and thermogravimetric analysis) and morphologically by Scanning Electron Microscopy (SEM). The results obtained were compared with HIPS matrix properties, without PSB and graphene oxide addition. From the thermal analyzes, composite samples showed higher decomposition temperatures compared to pure high-impact polystyrene especially in the thermogravimetric analysis results, showing a considerable increase in the temperature at which material decomposition begins (322 °C for pure high-impact polystyrene and 380 °C for the composite).

    Palavras-Chave: composite materials; polystyrene; graphene; oxides; nanocomposites; aluminium compounds

  • IPEN-DOC 25623

    MIRANDA, LEILA F. de; MUNHOZ JUNIOR, ANTONIO H.; MASSON, TEREZINHA J.; SILVA, LEONARDO G. de A. e ; FRIEHE, KARL. Characterization of antistatic packaging based on PET/rGO. In: LI, BOWEN (Ed.); LI, JIAN (Ed.); IKHMAYIES, SHADIA (Ed.); ZHANG, MINGMING (Ed.); KALAY, YUNUS E. (Ed.); CARPENTER, JOHN S. (Ed.); HWANG, JIANN-YANG (Ed.); MONTEIRO, SERGIO N. (Ed.); BAI, CHENGUANG (Ed.); ESCOBEDO-DIAZ, JUAN P. (Ed.); SPENA, PASQUALE R. (Ed.); GOSWAMI, RAMASIS (Ed.). Characterization of Minerals, Metals, and Materials. Cham, CZ, Switzerland: Springer Nature Switzerland AG, 2019. p. 523-534, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-030-05749-7_52

    Abstract: Package for electronic components is one that protects an electronic or electrical device against electrostatic discharge. Traditionally, antistatic packages are produced with polystyrene (PS) or polypropylene (PP) filled with carbon black. Recently, studies have been carried out successfully for the application of polyethylene terephthalate (PET) filled with carbon black. This work aimed to obtain and characterize nanocomposites based on PET filled with reduced graphene oxide (rGO) and compare its physicochemical properties with PET filled with carbon black and PP filled with carbon black used in anti-static packaging. PET compounds containing 0.1; 0.3; 0.5 and 0.7wt% reduced graphene oxide were obtained by the modified Hummers process from the graphite and reduced with hydrazine. The thermomechanical, electrical and morphological properties of the obtained compounds were determined. The results showed that the addition of reduced graphene oxide to PET causes an increase in the melt flow index, also increase the tensile strength and electrical conductivity. The addition of reduced graphene oxide promotes the decrease in the hardness and thermal resistance of the obtained nanocomposites. Nanocomposites based on PET containing 0.5wt% and 0.7wt% reduced graphene oxide can be used in the handling, transport and storage of electronic components since their mechanical, thermal and resistivity properties are satisfactory for this purpose.

    Palavras-Chave: nanocomposites; polyethylene terephthalate; graphene; oxides; packaging

  • IPEN-DOC 21801

    INAMURA, P.Y. ; KRAIDE, F.H. ; ARMELIN, M.J.A. ; SCAPIN, M.A. ; MOURA, E.A.B. ; MASTRO, N.L. . Characterization of Brazil nut fibers. In: FANGUEIRO, R. (Ed.); RANA, S. (Ed.). Natural fibers: advances in science and technology towards industrial applications. Netherlands: Springer International Publishing, 2016. p. 71-85, (RILEM Bookseries, 12).

    Palavras-Chave: brazil; nuts; fibers; capsules; shells; organic compounds; neutron activation analysis; gamma spectroscopy; x-ray fluorescence analysis; fluorescence spectroscopy; cellulose

  • IPEN-DOC 27624

    MIRANDA, LEILA F. de; BARBOSA, ISABELLA T.F.; MASSON, TEREZINHA J.; MUNHOZ JUNIOR, ANTONIO H.; SILVA, LEONARDO G. de A. e ; GONÇALVES, ALEKSANDRA A.A.. Characterization of hydrogels for release of cosmetic assets containing nanoemulsions of mandellic acid in different concentrations of pseudoboehmite. In: LI, JIAN (Ed.); ZHANG, MINGMING (Ed.); LI, BOWEN (Ed.); MONTEIRO, SERGIO N. (Ed.); IKHMAYIES, SHADIA (Ed.); KALAY, YUNUS E. (Ed.); HWANG, JIANN-YANG (Ed.); ESCOBEDO-DIAZ, JUAN P. (Ed.); CARPENTER, JOHN S. (Ed.); BROWN, ANDREW D. (Ed.). Characterization of Minerals, Metals, and Materials. Cham, CZ, Switzerland: Springer Nature Switzerland AG, 2020. p. 477-489, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-030-36628-5_47

    Abstract: Hydrogel is a gel formed by a three-dimensional network of hydrophilic polymers that are used as advanced asset release systems with good biocompatibility. The use of ionizing radiation to obtain hydrogels promotes cross-linking with the concomitant sterilization of the hydrogels. Aiming at the release of the mandelic acid (an active cosmetic), hydrogels were prepared using different concentration of poly(N-vinyl-2-pyrrolidone) (PVP), poly(ethylene glycol) (PEG) and agar containing nanoparticles of the pseudoboehmite, mandelic acid and Palmarosa and Rosa Mosqueta oils nanoemulsions, submitted to irradiation dose of 25 kGy. Hydrogels containing 7.5 wt% PVP showed better absorption, slip, odor results, and those with 10 wt% PVP were found to be inadequate. Nanoemulsions were characterized by acidity, density and optical microscopy; hydrogels samples were put under isothermal dehydration with air entrainment and dehydration was examined as a function of time. The results showed that the composition of hydrogels is stable, and the increase of the concentration of pseudoboehmite in hydrogels sample containing Palmarosa oil suffers less dehydration and those containing the two oils showed an increase in dehydration. The hydrogels obtained with 7.5 wt% of PVP and 3 wt% of pseudoboehmite, Rosa Mosqueta vegetable oil and mandelic acid are most suitable to be used in cosmetic products.

    Palavras-Chave: hydrogels; mandelic acid; pvp; consumer products

  • IPEN-DOC 24662

    FRANCISCO, DANAE L. ; PAIVA, LUCILENE B. de; ALDEIA, WAGNER; LUGAO, ADEMAR B. ; MOURA, ESPERIDIANA A.B. . Characterization of non-covalently functionalized halloysite. In: LI, BOWEN (Ed.); LI, JIAN (Ed.); IKHMAYIES, SHADIA (Ed.); ZHANG, MINGMING (Ed.); KALAY, YUNUS E. (Ed.); CARPENTER, JOHN S. (Ed.); HWANG, JIANN-YANG (Ed.); MONTEIRO, SERGIO N. (Ed.); FIRRAO, DONATO (Ed.); BROWN, ANDREW (Ed.); BAI, CHENGUANG (Ed.); PENG, ZHIWEI (Ed.); ESCOBEDO-DIAZ, JUAN P. (Ed.); GOSWAMI, RAMASIS (Ed.); KIM, JEONGGUK (Ed.). Characterization of Minerals, Metals, and Materials. TMS. Cham, CZ, Switzerland: Springer International Publishing AG, 2018. p. 317-323, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-319-72484-3_34

    Abstract: The inorganic nanotube halloysite (HNT) is a promising type of natural occurring filler for polymers. Its characteristics, such as high aspect ratio (10–50), small size, and high strength (elastic modulus—140 GPa) suggest that HNTs have a potential use in high-performance polymer nanocomposites. Compared to other nanoclays and nanosilica the relatively low content of hydroxyl groups on their surfaces makes HNTs relatively hydrophobic, although, sometimes, this is not sufficient for guaranty a good interfacial adhesion in composite systems. Further hydrophobic treatment is required to improve HNTs compatibility with polymer matrixes, maximizing interfacial interactions. In the present study, different percentages of EPB (2,2-(1,2-ethene diyldi-4,1-phenylene) bisbenzoxazole) was used to perform a non-covalent functionalization of halloysite, based on electron transfer interactions. The functionalization is characterized by specific surface area (BET), thermogravimetric analysis (TG) and water/toluene extraction experiment.

    Palavras-Chave: nanotubes; silicate minerals; clays; benzoxazoles; thermal gravimetric analysis; toluene; polymers

  • IPEN-DOC 22013

    CANDIOTO, KATIA C.G.; CALIARI, FELIPE R.; REIS, DANIELI A.P.; COUTO, ANTONIO A. ; NUNES, CARLOS A.. Characterization of the superalloy inconel 718 after double aging heat treatment. In: OSCHSNER, A. (Ed.); ALTENBACH, H. (Ed.). Mechanical and materials engieering of modern structure and component design. Switzerland: Springer International Publishing, 2015. p. 293-300, (Advance Structure Materials, 70).

    Palavras-Chave: heat resisting alloys; inconel 718; aging; heat treatments; microstructure; solid solutions; laves phases; x-ray diffraction; scanning electron microscopy

  • IPEN-DOC 28891

    VIGATO, ARYANE A.; MACHADO, IAN P.; FRANCO, MARGARETH K.K.D. ; YOKAICHIYA, FABIANO; SAIRRE, MIRELA I. de; ARAUJO, DANIELE R. de. Chemical and structural characterization of hybrid delivery systems studied by FTIR, NMR, and SAS techniques. In: KESHARWANI, P. (Ed.); JAIN, N.K. (Ed.). Hybrid Nanomaterials for Drug Delivery. Cambridge, MA, United States: Woodhead Publishing, 2022. p. 27-51, cap. 2. (Woodhead Publishing Series in Biomaterials). DOI: 10.1016/B978-0-323-85754-3.00005-8

    Abstract: In recent years, the research for new classes of materials for biomedical applications has directed the synthesis and design of hybrid systems composed of two or more components (metals, clays, ceramics, bioglass, polymers, lipids, enzymes) conferring to them multifunctional properties, in general synergistic, different to those obtained for their parent components. One of the main advantages attributed to hybrid systems is their ability to modulate the drug release rate into the biological medium, which improve their therapeutic efficacy. However, this enhanced biomedical performance is a result of chemical interactions among material components that assume different levels of structural organization. This chapter provides a discussion about applications of three physicochemical techniques used for characterizing those materials, Fourier-transform infrared spectroscopy, nuclear magnetic resonance, and small-angle scattering. Therefore a brief introduction on fundamental techniques followed by a discussion on relationships between composition and main chemical and structural finding are covered.

    Palavras-Chave: nanomaterials; medical supplies; drug delivery; hybrid systems

  • IPEN-DOC 22480

    DUARTE, R.C. ; FANARO, G.B.; SANTANA, J.; GASPAR, E.M.M.S.; VILLAVICENCIO, A.L.C.H. . Cinnamomum zeylanicum Blume and Myristica fragrans Houtt essential oils as bio-pesticides against the fungus Guignardia citricarpa. In: MENDEZ VILAS, A. (Ed.). The battle against microbial pathogens: basic science, technological advances and educational programs. Badajoz, Espanha: Formatex Research Center, 2015. p. 125-130, (Microbiology book series).

    Palavras-Chave: essential oils; fungal diseases; fungicides; spices; herbs; pesticides; distillation; gas chromatography; mass spectroscopy

  • IPEN-DOC 28545

    VIEIRA, RODRIGO R.; SOUSA, IASCHCARA G.L. de; OLIVEIRA, EDUARDO M. de; GARCEZ, AGUINALDO S. . Cirurgia. In: NUNEZ, SILVIA C. (Org.); GARCEZ, AGUINALDO S. (Org.); RIBEIRO, MARTHA S. (Org.). Aplicações clínicas do laser na odontologia. Barueri, SP: Manole, 2021. p. 18-78, cap. 2.

    Palavras-Chave: dentistry; lasers; surgery; solid state lasers

  • IPEN-DOC 29291

    SANTOS, SOFIA N. dos ; NATALINO, RENATO J.M.; CHAMMAS, ROGER. Classificação e nomenclatura anatomopatológica de tumores. In: CHAMMAS, ROGER (Ed.); FOLGUEIRA, MARIA A.K. (Ed.); VILLA, LUISA L. (Ed.). Oncologia: da molécula à clínica. São Paulo, SP: Editora dos Editores, 2022. p. 13-23, cap. 2.

    Notas de conteúdo: Versão impressa disponível para consulta na biblioteca do IPEN.

  • IPEN-DOC 19976

    FUNGARO, DENISE A. ; IZIDORO, JULIANA C. ; SANTOS, FERNANDO S.; WANG, SHAOBIN. Coal fly ashes from Brazilian power plants: chemical and physical properties and leaching characteristics. In: SARKER, PRABIR K. (Ed.). Fly Ash: Chemical Composition, Sources and Potential Environmental Impacts. Nova Science Publishers: New York, USA, 2013.

    Palavras-Chave: brazil; coal; fly ash; thermal power plants; chemical properties; physical properties; leaching; waste disposal; safety

  • IPEN-DOC 26938

    SANTOS, VERONICA M.S.; SUSSA, FÁBIO V. ; GONÇALEZ, EDLAYNE; SILVA, PAULO S.C. ; FELICIO, JOANA D.. Comparative study of the essential oil effects on the Aspergillus flavus growth. In: PETERS, MIRANDA (Ed.). Essential Oils: Historical Significance, Chemical Composition, and Medicinal Uses and Benefits. Hauppauge, New York, USA: Nova Science Publishers, 2016. p. 139-152, cap. 8.

    Abstract: Essential oils of plant species have shown activity against a variety of pathogenic and toxigenic fungi. The toxigenic fungi can cause a lot of damage to food commodities, including mycotoxin production. The presence of molds and mycotoxins in food commodities is a potential risk to health of humans and livestock. The aflatoxins, mutagenic and carcinogenic substances, are mycotoxins produced especially by Aspergillus flavus and A. parasiticus. This work reports the comparative effects of the three essential oils leaves on growth of A. flavus and their chemical constitutions. The essential oils of Peperomia pellucida, Leunurus sibiricus and Porophyllum ruderale were obtained by hydrodistillation in a Clevenger-type apparatus, and their effects were evaluated in A. flavus culture. A. flavus growth was evaluated by disk diffusion assay. Filter paper disks containing 0.0, 2.5, 5.0, 7.5, and 10.0 μL of essential oils were used, and commercial fungicide was the positive control. All volumes of the three essential oils reduced the fungal growth when compared with that of the control (p < 0.05). The essential oil of P. ruderale showed the greatest inhibition effect. L. sibiricus essential oil showed fungicidal effect greater than that of P. pellucida essential oil (p < 0.05). The chemical composition of the essential oils used was determined by GC-MS analysis. The use of essential oils with lower toxicity than those from synthetic products can be a good alternative to A. flavus control.

    Palavras-Chave: essential oils; plants; botany; fungi; fungicides; aspergillus; aflatoxins

  • IPEN-DOC 25624

    MONTEIRO, ALEX S. ; BARREIRA, DAILI A.S. ; BARTOLOMEI, SUELLEN S. ; OLIVEIRA, RENE R. ; MOURA, ESPERIDIANA A.B. de . Comparative study of the use of rice husk ashes and graphite as fillers in polypropylene matrix composites. In: LI, BOWEN (Ed.); LI, JIAN (Ed.); IKHMAYIES, SHADIA (Ed.); ZHANG, MINGMING (Ed.); KALAY, YUNUS E. (Ed.); CARPENTER, JOHN S. (Ed.); HWANG, JIANN-YANG (Ed.); MONTEIRO, SERGIO N. (Ed.); BAI, CHENGUANG (Ed.); ESCOBEDO-DIAZ, JUAN P. (Ed.); SPENA, PASQUALE R. (Ed.); GOSWAMI, RAMASIS (Ed.). Characterization of Minerals, Metals, and Materials. Cham, CZ, Switzerland: Springer Nature Switzerland AG, 2019. p. 561-570, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-030-05749-7_56

    Abstract: In recent years, carbonaceous materials have been widely studied for polymer composite applications due to its capability to improve the engineering properties of the polymeric matrix. Among various carbonaceous fillers, carbon nanotube, graphene, and graphite promise to be a suitable reinforcement of polymers. Rice husk ash (RHA), a large residue rich in carbon and silica produced by the burning of rice husk offers also an immense potential as a carbonaceous filler for polymer composites on account of its lowcost, lowdensity, high strength and elastic modulus, no health risks, and renewability. This work aims at studying the effects of RHA and graphite as fillers in polypropylene (PP) matrix composites. The composites PP/RHA and PP/graphite were produced by melting extrusion process. The materials obtained were subjected to mechanical tests, XRD, TG, and FEG-SEM analyses. Comparison studies between neat PP properties and its composites were carried out.

    Palavras-Chave: matrix materials; polypropylene; mechanical properties; thermodynamic properties; carbonaceous materials

  • IPEN-DOC 27622

    SOARES, CARLOS ; SANTANA, JULYANA ; GUVEN, OLGUN; MOURA, ESPERIDIANA A.B. . A comparison between graphene oxide and reduced graphene oxide as reinforcement agents in polypropylene nanocomposite using irradiated polypropylene as compatibilizer. In: LI, JIAN (Ed.); ZHANG, MINGMING (Ed.); LI, BOWEN (Ed.); MONTEIRO, SERGIO N. (Ed.); IKHMAYIES, SHADIA (Ed.); KALAY, YUNUS E. (Ed.); HWANG, JIANN-YANG (Ed.); ESCOBEDO-DIAZ, JUAN P. (Ed.); CARPENTER, JOHN S. (Ed.); BROWN, ANDREW D. (Ed.). Characterization of Minerals, Metals, and Materials. Cham, CZ, Switzerland: Springer Nature Switzerland AG, 2020. p. 385-394, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-030-36628-5_36

    Abstract: Graphene is thematerial with the bestmechanical resistance ever encountered. Various types of studies have been carried out on possible applications. The use as a reinforcement in nanocomposites has shown to be a promising field, but some studies indicate that the graphene oxide (GO) and reduced graphene oxide (RGO) have better results as reinforcement, due to the functional groups,which allowa better adhesion with the matrix. This study analyzes the production of polypropylene (PP) nanocomposite comparing the use of graphene oxide (GO) and reduced graphene oxide (RGO) as fillers and irradiated polypropylene as a coupling agent.Atwin-screw extruder and injection molding machine were used to produce the nanocomposite PP reinforced with 0.2 wt% of GO and RGO by melt blending. The GO and RGO were characterized byXRDanalysis.The nanocomposite sampleswere characterized by XRD, SEM, TG, DSC and mechanical test.

    Palavras-Chave: graphene; oxides; polypropylene; nanocomposites; gamma radiation; stresses; tensile properties

  • IPEN-DOC 21589

    NISTI, M.B. ; FERREIRA, A.O. ; CAMPOS, M.P. ; SAUEIA, C.H.R. ; MAZZILLI, B.P. . A comparison of analytical methods for screening gross alpha and beta radioactivity in water by liquid scintillation counting and gas flow proportional counting. In: WARWICK, PETER (Ed.). Environmental radiochemical analysis, V. London: Royal Society of Chemistry, 2015. p. 148-151, cap. 18. DOI: 10.1039/9781782622734-00148

    Palavras-Chave: radioactivity; drinking water; recommendations; radium 226; radium 228; alpha detection; beta detection; comparative evaluations; liquid scintillation detectors; measuring methods; screening; gas flow

  • IPEN-DOC 13909

    QUINLAN, MERVIN; PLUCKNETT, KEVIN P.; GARRIDO, LILIANA; GENOVA, LUIS . Compositional design of porous beta-Sisub(3)Nsub(4) prepared by pressureless-sintering compositions in the Si-Y-Mg-(Ca)-O-N system. In: BRITO, MANUEL (Ed.); CASE, ELDON (Ed.); KRIVEN, WALTRAUD M. (Ed.). Developments in Porous, Biological and Geopolymer Ceramics: Ceramic Engineering and Science Proceedings. American Ceramic Society: 2007, 2007. p. 48-56,

    Palavras-Chave: porous materials; ceramics; silicon nitrides; sintering; additives; nitrogen; kinetics

  • IPEN-DOC 18769

    BARRAGAN NETO, VALTER; COUTO, ANTONIO A. ; VATAVUK, JAN. Computational simulation in centrifugal casted aluminium - silicon engine cylinder liner. In: OCHSNER, ANDREAS (Ed.); SILVA, LUCAS F.M. da (Ed.); ALTENBACH, HOLM (Ed.). Materials with Complex Behaviour II. Springer-Verlag: Berlin Heidelberg, 2012. p. 81-98,

    Palavras-Chave: computerized simulation; h codes; centrifuges; casting; aluminium; silicon; cylinders; liners; automotive accessories

  • IPEN-DOC 18761

    SILVA, DANIELA de F.T. da; LOPES, LUCIANA A.; RIBEIRO, MARTHA S. . Conceitos físicos básicos aplicados à terapia laser de baixa potência. In: NUNEZ, SILVIA C. (Ed.); GARCEZ SEGUNDO, AGUINALDO S. (Ed.); RIBEIRO, MARTHA S. (Ed.). Laser de baixa potência. Principios básicos e aplicações clínicas na odontologia. Elsevier Brasil: Rio de Janeiro, RJ, 2012. p. 1-13,

    Notas de conteúdo: Capitulo 1

    Palavras-Chave: laser radiation; therapy; low dose irradiation; dentistry

  • IPEN-DOC 23237

    OLIANI, WASHINGTON L. ; PARRA, DUCLERC F. ; LIMA, LUIS F.C.P. ; OTAGURO, HARUMI; FERRETO, HELIO F.R. ; LUGAO, ADEMAR B. . Contribution to the β relaxation study of the HDPE, LDPE and LLDPE. In: IKHMAYIES, SHADIA (Ed.); LI, BOWEN (Ed.); CARPENTER, JOHN S. (Ed.); LI, JIAN (Ed.); HWANG, JIANN-YANG (Ed.); MONTEIRO, SERGIO N. (Ed.); FIRRAO, DONATO (Ed.); ZHANG, MINGMING (Ed.); PENG, ZHIWEI (Ed.); ESCOBEDO-DIAZ, JUAN P. (Ed.); BAI, CHENGUANG (Ed.); KALAY, YUNUS E. (Ed.); GOSWAMI, RAMASIS (Ed.); KIM, JEONGGUK (Ed.). Characterization of Minerals, Metals, and Materials. Gewerbestrasse, Switzerland: Springer International Publishing AG., 2017. p. 617-626, (The Minerals, Metals & Materials Series).

    Abstract: The activation of three polyethylenes, the low density, the high density and the linear low density polyethylene, was determined by means of dynamic mechanical analysis (DMA). Storage modulus and tan δ spectra were obtained as a function of the temperature from −60 to 50 °C with a heating rate of 2° min−1 at frequencies of 1, 2 and 5 Hz and measurement strain amplitude of 10−5. In the tan δ spectra, a small peak in the β region of the three polyethylenes was found and substantiated by subtracting the growing exponential background. This procedure was based on a model that associates the dislocation motion on metals under cyclic stress to vibrating strings and considering the same for the polymeric chains. For the determination of the activation energy we have utilized the frequency versus the reciprocal of the absolute temperature peak of the tan δ. The values obtained for the three polyethylenes, the low density, the high density and the linear low density were, 362 ± 12, 266 ± 9 and 197 ± 6 kJ mol−1, respectively, which were compared with those presented in the literature.

    Palavras-Chave: polyethylenes; relaxation; activation energy; density

  • IPEN-DOC 26720

    ZEZELL, DENISE M. ; SILVA JUNIOR, DANIEL S. da; MOTA, CLAUDIA C.B. de O.. Correção minimamente invasiva do sorriso. In: BRUGNERA JUNIOR, ALDO (Coord.); ZANIN, FATIMA (Coord.); NAMOUR, SAMIR (Coord.); SHIBLI, JAMIL A. (Coord.). Laser em odontologia: de clínico para clínico. São Paulo, SP: VW Cultural, 2019. p. 230-237, cap. 24.

    Palavras-Chave: dentistry; lasers; optical fibers; diode tubes

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.