978 resultados para Long-Base-Line
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Pós-graduação em Química - IBILCE
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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In the present work it was studied the behavior of four water bath curing cycles of heat activated acrylic resin considered as long duration (I – 65ºC for 30 min;50ºC for 23h and 30min; and 100º C for 1h; II- 50ºC for 24h and the rapid cycle), compared to the known long time curing cycle (9 hours for 72ºC) and short curing cycle (1 h for 65ºC; 30 min to elevate at 100º C and 1:00 to 100º C). Analysis consisted of observations and verification of the residual monomer, weight alterations, dimensional, dimensional lineal, porosity and hardness to determine material performance. The results pointed out that residual monomer presented statistical significant differences in the factor storage and interaction among the factors cycle X storage for weight alteration; statistical significant differences for the factor storage for lineal dimensional alterations, without significant differences for hardness. Porosity was verified in minimum degree in the cycle III and in appreciable amount in the cycle IV
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This research seeks to demonstrate the scientific collaboration in the field of Information Science, specifically in the thematic indexing, by analyzing the co-authors network, based on scientific collaboration in Brazilian journals online, according to CAPES. We selected six Brazilian journals online, namely: Ciência da Informação; Transinformação; Perspectivas da Ciência da Informação; Encontros BIBLI: Revista Eletrônica de Biblioteconomia e Ciência da Informação; DataGramaZero and Em Questão, totaling 25 articles. It was built in coauthorship network, using Pajek software in order to evaluate interactions between researchers and cohesion of the network by calculating its density.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Pós-graduação em Odontologia - FOAR
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This research project focused primarily on assessing the impact toughness of the weld and the base material of a steel pipe API 5L X70 submerged arc welded, used to conduct remote oil and gas (linepipes). The analysis followed strictly the Specification for Line Pipe - API 5L Standard, regarding the removal of the specimens of regions-of-proof-long section of the pipe, at 90o and 180o from the welded joint, and mechanical properties of toughness and Charpy-V, both the joint welded as the base material. Specimens of steel tube supplied by Tenaris Confab-SA were sized for tensile and Charpy-V, according to ASTM E 8M and ASTM E23, respectively. The result obtained showed that the API X70 steel tube has high Charpy-V toughness, near to each other at both 90o and 180o from the welded joint of the tube, and both higher than the weld metal. Microstructural and microhardness analysis complemented the present study
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This paper presents the development of a Web application called CityFreedom based on 3D modeling. The developed system demonstrates the use of most revolutionary and innovative techniques to create Web portals with the integrated 3D navigation scenarios to their own pages, without requiring any kind of plug-ins or external software. Everything works on the basis of compatible browsers. The CtyFreedom aims to give the user the feeling of immersion in virtual reality so get to interact with a three-dimensional city in order to see new places, traveling in an area of town that has always thought of knowing or even analyze establishments long before attend-them. It's the freedom to know and traveling around the city in a simple and trivial way. It is a new trend, the future of Web systems development
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This study aimed to evaluate the physico-mechanical performance of three PVA adhesive formulations according to the Brazilian standards for plywood testing and to evaluate the results with those presented in the technical literature and specified in normative documents. The study presents the production process of the panels, the obtaining of samples and, finally, the implementation of physico-mechanical characterization tests based on plywood Brazilian standards. For the panels production it was used a gramature of 120 g / m² and applied a pressure of 15 bars and two temperature combinations and pressing time for each adhesive. The commercial adhesives used were PVA 1810, PVA 1060 and Vinyltec 239. The physical tests conducted were thickness swelling, density, moisture content and water absorption. The mechanical tests were static flexion, for the determination of elasticity modulus (MOE) and rupture modulus (MOR), and shear in the glue line. Among the three formulations studied none showed good performance in the presence of water. However, other trials in the adhesive showed better results and closer to the commercially equivalent used, in the case the urea-formaldehyde, was the PVA 1810, that can be applied in non-structural uses and in environments without the presence of moisture
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Pós-graduação em Odontologia - FOAR
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Educação Escolar - FCLAR
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This article aims to trace a historical development of language teacher education in Brazil and abroad, as well as to discuss the tenets of Vygotsky’s sociocultural perspective as a theoretical basis on which teacher development can be anchored in the contemporary world. Since learning to teach is now understood as a complex and long process of development, which results from the participation in social practices and contexts associated with teaching and learning, we intend to discuss how such a theory is in line with an interpretive view of reality and provides elements for the (re)construction and transformation of teaching practices. In this view, knowledge is understood as intimate and dynamically linked to experience, highlighting the role of human agency in our own development.
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The aim of this in vitro study was to evaluate the trans-enamel and transdentinal cytotoxic effects of two in-office tooth bleaching techniques that employ bleaching gels containing 20% and 38% of H2 O2 on cultured odontoblast-like cell line (MDPC-23). Sixty enamel/dentin discs were obtained from bovine central incisors and placed individually in artificial pulp chambers. Six groups were formed according to the following enamel treatments: G1- 20% H2 O2 (1 application); G2- 20% H2 O2 (2 applications); G3- 38% H2 O2 (1 application); G4- 38% H2 O2 (2 applications); G5- 38% H2 O2 (3 applications); and G6- control (no treatment). In G1 and G2, the bleaching gel was left in contact with the enamel surface for 45 min in each application. However, in G3, G4, and G5 the bleaching gel was applied for only 10 min per application. After the last application, the extracts were collected and applied on previously cultured cells (30.000 cells/cm2 ) for 24 h. Cell metabolism was evaluated by the MTT assay and cell morphology was analysed by scanning electron microscopy. Cell metabolism decreased by 96.29%; 96.11%; 96.42%; 95.62%; and 97.18% in G1, G2, G3, G4, and G5, respectively. All treated groups differed significantly from non-treated control group (G6) (p < 0.05). However, the difference in cell metabolism among treated groups was not significant statistically. In addition, significant morphological cell alterations were observed in all treated groups. Under the tested experimental conditions, the extracts collected after both tooth bleaching techniques evaluated in this study caused severe toxic effects on cultured odontoblast-like cell MDPC-23.
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We present the results of airborne measurements of carbon monoxide (CO) and aerosol particle number concentration (CN) made during the Balan double dagger o Atmosf,rico Regional de Carbono na Amazonia (BARCA) program. The primary goal of BARCA is to address the question of basin-scale sources and sinks of CO2 and other atmospheric carbon species, a central issue of the Large-scale Biosphere-Atmosphere (LBA) program. The experiment consisted of two aircraft campaigns during November-December 2008 (BARCA-A) and May-June 2009 (BARCA-B), which covered the altitude range from the surface up to about 4500 m, and spanned most of the Amazon Basin. Based on meteorological analysis and measurements of the tracer, SF6, we found that airmasses over the Amazon Basin during the late dry season (BARCA-A, November 2008) originated predominantly from the Southern Hemisphere, while during the late wet season (BARCA-B, May 2009) low-level airmasses were dominated by northern-hemispheric inflow and mid-tropospheric airmasses were of mixed origin. In BARCA-A we found strong influence of biomass burning emissions on the composition of the atmosphere over much of the Amazon Basin, with CO enhancements up to 300 ppb and CN concentrations approaching 10 000 cm(-3); the highest values were in the southern part of the Basin at altitudes of 1-3 km. The Delta CN/Delta CO ratios were diagnostic for biomass burning emissions, and were lower in aged than in fresh smoke. Fresh emissions indicated CO/CO2 and CN/CO emission ratios in good agreement with previous work, but our results also highlight the need to consider the residual smoldering combustion that takes place after the active flaming phase of deforestation fires. During the late wet season, in contrast, there was little evidence for a significant presence of biomass smoke. Low CN concentrations (300-500 cm(-3)) prevailed basinwide, and CO mixing ratios were enhanced by only similar to 10 ppb above the mixing line between Northern and Southern Hemisphere air. There was no detectable trend in CO with distance from the coast, but there was a small enhancement of CO in the boundary layer suggesting diffuse biogenic sources from photochemical degradation of biogenic volatile organic compounds or direct biological emission. Simulations of CO distributions during BARCA-A using a range of models yielded general agreement in spatial distribution and confirm the important contribution from biomass burning emissions, but the models evidence some systematic quantitative differences compared to observed CO concentrations. These mismatches appear to be related to problems with the accuracy of the global background fields, the role of vertical transport and biomass smoke injection height, the choice of model resolution, and reliability and temporal resolution of the emissions data base.