3 resultados para Functionalized nanotubes

em Universidade Federal do Rio Grande do Norte(UFRN)


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The natural gas is an alternative source of energy which is found underground in porous and permeable rocks and being associated or not to the oil. Its basic composition includes methane, other hydrocarbon and compounds such as carbon dioxide, nitrogen, sulphidric gas, mercaptans, water and solid particles. In this work, the dolomite mineral, a double carbonate of calcium and magnesium whose the chemical formula is CaMg(CO3)2, was evaluated as adsorbent material. The material was characterized by granulometric analysis, X-ray fluorescence, X-ray diffraction, thermogravimetric analysis, differential thermal analysis, specific surface area, porosity, scanning electronic microscopy and infrared spectroscopy. Then the material was functionalized with diethanolamine (dolomite+diethanolamine) and diisopropylamine (dolomite+diisopropylamine). The results indicated that the adsorbents presented appropriate physiochemical characteristics for H2S adsorption. The adsorption tests were accomplished in a system coupled to a gas chromatograph and the H2S monitoring in the output of the system was accomplished by a pulsed flame photometric detector (PFPD). The adsorbents presented a significant adsorption capacity. Among the analyzed adsorbents, the dolomite+diethanolamine presented the best capacity of adsorption. The breakthrough curves obtained proved the efficiency of this process

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Currently the search for new materials with properties suitable for specific applications has increased the number of researches that aim to address market needs. The poly (methyl methacrylate) (PMMA) is one of the most important polymers of the family of polyacrylates and polymethacrylates, especially for its unique optical properties and weathering resistance, and exceptional hardness and gloss. The development of polymer composites by the addition of inorganic fillers to the PMMA matrix increases the potential use of this polymer in various fields of application. The most commonly used inorganic fillers are particles of silica (SiO2), modified clays, graphite and carbon nanotubes. The main objective of this work is the development of PMMA/SiO2 composites at different concentrations of SiO2, for new applications as engineering plastics. The composites were produced by extrusion of tubular film, and obtained via solution for application to commercial PMMA plates, and also by injection molding, for improved the abrasion and scratch resistance of PMMA without compromising transparency. The effects of the addition of silica particles in the polymer matrix properties were evaluated by the maximum tensile strength, hardness, abrasion and scratch resistance, in addition to preliminary characterization by torque rheometry and melt flow rate. The results indicated that it is possible to use silica particles in a PMMA matrix, and a higher silica concentration produced an increase of the abrasion and scratch resistance, hardness, and reduced tensile strength

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The constitutionalisation of private relations is the central theme of this work. Approached him overcome the dichotomy between public and private, through functionalization to the constitutionalization of civil law. Research on the effectiveness of horizontal rights. Constitutional under the lens, we analyzed the tense relationship between possession and ownership desfuncionalizada functionalized. We realize that having qualified and gained autonomy, and mechanism of access to goods, in view of the status sheet minimum, and of accomplishment, materializing human dignity. Then, we investigated the expropriation of private ownership qualified as legislative intervention that ensures the enforcement of fundamental rights through the state-court. We face the legal, the constitutionality and the burden of this institute. Also operability that it gives the judge, the process of exercise, the object, issues related to the burden and assessment of damages, as well as the nature, timing and costs of transferring property. At the end, we point to the scarcity palace, as well as the need to repair lege ferenda. The methodological approach has been championed by legal dogmatics in its analytical aspect, as we explore concepts and correlate with our planning. In empirical connotation, we evaluated the normativity and applicability of our law courts. For the ultimate in normative vision, answers to the problems faced and perform the necessary propositions, based on the results from the conceptual and empirical analysis