1000 resultados para arroz em casca
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Imagem componente do jogo “DigesTower (http://www.loa.sead.ufscar.br/digestower.php)” desenvolvido pela equipe do Laboratório de Objetos de Aprendizagem da Universidade Federal de São Carlos (LOA/UFSCar).
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The MCM-41 mesoporous synthesis was done using rice hulls ash and chrysotile as natural alternative silica sources. For the using of these sources, chemical and thermic treatments were done in both materials. After chemical and thermic treatments, these materials were employed on the MCM-41 mesoctructures synthesis. The natural materials treated and employed in the synthesis were characterized by several techniques such as X-ray diffraction, N2 adsorption and desorption, scanning electronic microscopy and thermogravimetric analysis. MCM-41 standart samples synthetized with aerosil 200 commercial sílica were used to evaluation. The formed material from rice hulls ash showed values from BET specific area about 468 m².g-1, N2 adsorption and desorption isotherms and loss mass similar to reference materials. The silica from chrysotile calcined and leached was employed to mesoporous materials synthesis. The BET specific area showed values about 700 m².g-1, N2 adsorption and desorption isotherms type IV and loss mass similar to mesoporous materials. The formed material from calcined and leached chrysotile, without calcination, applied to phenol remotion carried high performance liquid chromatography and evaluated with organophilic clays with different treatments. By the characterization techniques were proved that mesoporous materials with lesser order that reference samples. The material formed from rice hulls ash without the calcination step achieved better adsorption results than organophilic clays
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The industrial production of ornamental rocks and the burning of coffee husk generate waste that is discarded into the environment. However, with the study of the incorporation of these residues in ceramic products, may be found an alternative to reducing environmental impacts and detrimental effects on human health caused by its indiscriminate disposal of waste in nature. Thus, this work aimed to study the addition of ashes of the coffee husk and granite residue in matrix of red ceramic. The raw materials were dry milled and sieved to mesh 100. To characterize the raw materials were carried out analyzes of X-ray diffraction (XRD), X-ray fluorescence (XRF), particle size analysis (PSA), differential thermal analysis (DTA) and thermogravimetric analysis (TG). Six formulations were prepared where the clay content was kept constant (70%wt) and ashes contents and granite residue varied from 10, 15, 20 and 30%. Dilatometrics analyzes were performed at four selected formulations, containing them: 100% clay (A100); 70% clay and 30% ashes (A70C30); 70% clay and 30% granite residue (A70G30); and 70% clay, 15% granite residue and 15% ashes (A70G15C15). The samples were prepared by uniaxial compaction with pressure of 25 MPa, and fired at temperatures of 800°C, 850ºC, 900ºC, 950ºC, 1000ºC and 1100°C. Assays were performed to determine the linear shrinkage of burning (LSB), water absorption (WA), apparent porosity (AP), density (D) and tensile bending. Also were performed analyzes of X-ray diffraction (XRD) and scanning electron microscopy (SEM) of the samples fired. The formulations incorporating granite residue and/or ashes reached the required limits of water absorption according to NBR 15270-1 and NBR 15310 and tensile bending according to classical literature (SANTOS, 1989) necessary for the production of tiles and ceramic block for masonry sealing
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To produce porcelain tiles fluxing agents are used in order to obtain a liquid phase during firing. This liquid phase fills the pores decreasing porosity, water absorption and contributes to material densification. In the porcelain tiles industry, feldspar is the main flux material used, with quantities ranging between 35 and 50%. Studies focus on the discovery of materials with flux characteristics that can reduce the consumption of feldspar by porcelain tiles industry. In this context, the coffee husk ashes, a residue obtained when coffee husks are burned to produce heat for the dryers during the processing of the green fruit, have as main chemical constituents potassium, calcium and magnesium, giving them characteristics of fluxing material. Brazil is the largest coffee producer in the world and is responsible for over 30% of the world s production. In this work a physical treatment of coffee husk ash was carried out in order to eliminate the organic matter and, after this, two by-products were obtained: residual wastes R1 and R2. Both residues were added separately as single fluxes and also in association with feldspar in mixtures with raw materials collected in a porcelain industry located in Dias d Ávila-Ba. The addition of these residues aimed to contribute to the reduction of the consumption of feldspar in the production of porcelain tiles. Specimens were produced with dimensions of 60 mm x 20 mm x 6 mm in an uniaxial die with compacting pressure of 45 MPa. The samples were heated to a temperature of 1200 °C, for 8 minutes. Tests were performed to characterize the raw materials by XRF, XRD, particle size analysis, DTA and TGA and, additionally, the results of the physical properties of water absorption, apparent porosity, linear shrinkage, density, dilatometry, flexural strength and SEM of sintered body were analyzed. Additions of less than 8% of the residue R1 contributed to the decrease of porosity, but the mechanical strength of the samples was not satisfactory. Additions of 5% the R2 residue contributed significantly to decrease the water absorption and apparent porosity, and also to increase the mechanical strength. Samples with addition of feldspar associated with the R2 residue, in proportions of 6.7% of R2 and 6.7% of feldspar, led to results of water absorption of 0.12% and mechanical strength of 46 MPa, having parameters normalized to the manufacture of porcelain stoneware tiles
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The fast pyrolysis of lignocellulosic biomass is a thermochemical conversion process for production energy which have been very atratactive due to energetic use of its products: gas (CO, CO2, H2, CH4, etc.), liquid (bio-oil) and charcoal. The bio-oil is the main product of fast pyrolysis, and its final composition and characteristics is intrinsically related to quality of biomass (ash disposal, moisture, content of cellulose, hemicellulose and lignin) and efficiency removal of oxygen compounds that cause undesirable features such as increased viscosity, instability, corrosiveness and low calorific value. The oxygenates are originated in the conventional process of biomass pyrolysis, where the use of solid catalysts allows minimization of these products by improving the bio-oil quality. The present study aims to evaluate the products of catalytic pyrolysis of elephant grass (Pennisetum purpureum Schum) using solid catalysts as tungsten oxides, supported or not in mesoporous materials like MCM-41, derived silica from rice husk ash, aimed to reduce oxygenates produced in pyrolysis. The biomasss treatment by washing with heated water (CEL) or washing with acid solution (CELix) and application of tungsten catalysts on vapors from the pyrolysis process was designed to improve the pyrolysis products quality. Conventional and catalytic pyrolysis of biomass was performed in a micro-pyrolyzer, Py-5200, coupled to GC/MS. The synthesized catalysts were characterized by X ray diffraction, infrared spectroscopy, X ray fluorescence, temperature programmed reduction and thermogravimetric analysis. Kinetic studies applying the Flynn and Wall model were performed in order to evaluate the apparent activation energy of holoceluloce thermal decomposition on samples elephant grass (CE, CEL and CELix). The results show the effectiveness of the treatment process, reducing the ash content, and were also observed decrease in the apparent activation energy of these samples. The catalytic pyrolysis process converted most of the oxygenate componds in aromatics such as benzene, toluene, ethylbenzene, etc
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Blood constituents labelled with technetium-99m (99mTc) has been used with radiobiocomplexes in several procedures in nuclear medicine. Some natural and sintetic drugs are capable to interfere on the labeling of blood constituents with 99mTc, on the morphology of red blood cells (RBC) and on the biodistribution of radiobiocomplexes. The aim of this study was evaluate the effect of an extract of Passiflora edulis f. flavicarpa on the labeling of blood constituints with 99mTc, on the morphology of RBC and on the biodistribution of the radiopharmaceutical sodium perthecnetate in Wistar rats. On the in vitro studies the Passiflora edulis f. flavicarpa decreased significantly (p<0.05) the %ATI on plasma proteins and on the in vitro morhology of RBC, the passion fruit peel flour altered the shape and the perimeter/área ratio. On the in vivo estudies the extract did not altered the %ATI in blood constituents, and did not altered the shape of RBC. Although, on the biodistribution of the radiobiocomplex sodium perthecnetate (Na99mTcO4) this extract decreased significantly (p<0.05) the uptake in duodenum, spleen, pâncreas and blood, and increased the uptake in stomach. It can be suggested that the effects presented by this extract could be a result of some substances contained in this extract that could alter the binding of 99mTc to plasma proteins, the morphology of RBC and the biodistribution of the radiobiocomplex sodium perthecnetate. This study was multidisciplinary experimental research. It was developed with the contribution of different Departments and Services of the Hospital Universitário Pedro Ernesto of the Universidade Estadual do Rio de Janeiro
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Our object of study in this work concerns to the movement of fight for the housing in the Great João Pessoa, Paraíba, Brazil, and looks for to investigate the conditions and context of the occupations of building, public or private, for devoid populations that do not have where to live. Front to the absence of politics effective directed to the habitation or the cities, in a picture of unemployment and impoverishment of the population, the result of the habitation point of view, is the absolute lack of popular housings, the degradation of the cities and the growth of the number of homeless and also of its occupations. The urban occupations today represent a reply of these devoid populations that from an involvement with parties or Not Governmental Organizations, and social movements leave for the class action known by the occupation of abandoning public or private buildings. These occupations, even so initially if assume as pressure instrument or of visibility for attainment of housings, for the delay in obtaining the attention of the public agencies and a solution for the problem, becomes definitive or is drawn out per many years. E this if gives although the deficiencies, of the accumulation or families neither in an adequate, always precarious space nor in sanitary installations, that the necessary privacy does not allow. The study it consisted of an empirical research, through the participant comment and open and half-open interviews, and counted on the audiovisual register of two occupations, one in the downtown of João Pessoa City (old building of the INSS, in the Ponto dos Cem Réis) and other (Community of the Cajueiro), next to the Beach "Praia do Jacaré", in the city of Cabedelo.The choice of the Visual Anthropology as research instrument is on to a concern in better translating other ways of life, therefore the accomplishment of the video in allows them to know with more precision the reality where the citizens of the research live. We also use as methodological resource in the research the deepened interview, in intention to better understand the description of the way of life of the studied families and the movements of fight for the housing, particularly the MDM - Movement of Right for the Housing, and the MNLM- Nacional Movement of Fight for the Housing