932 resultados para cinza óssea


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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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Cementing operation is one of the most important stages in the oil well drilling processes and has main function to form hydraulic seal between the various permeable zones traversed by the well. However, several problems may occur with the cement sheath, either during primary cementing or during the well production period. Cements low resistance can cause fissures in the cement sheath and compromise the mechanical integrity of the annular, resulting in contamination of groundwater and producing zones. Several researches show that biomass ash, in particular, those generated by the sugarcane industry have pozzolanic activity and can be added in the composition of the cementing slurries in diverse applications, providing improvements in mechanical properties, revenue and cement durability. Due to the importance of a low cost additive that increases the mechanical properties in a well cementing operations, this study aimed to potentiate the use of sugarcane bagasse ash as pozzolanic material, evaluate the mechanisms of action of this one on cement pastes properties and apply this material in systems slurries aimed to cementing a well with 800 m depth and geothermal gradient of 1.7 °F/100 ft, as much primary cementing operations as squeeze. To do this, the ash beneficiation methods were realized through the processes of grinding, sifting and reburning (calcination) and then characterization by X-ray fluorescence, XRD, TG / DTG, specific surface area, particle size distribution by laser diffraction and mass specific. Moreover, the ash pozzolanic activity added to the cement at concentrations of 0%, 20% and 40% BWOC was evaluated by pozzolanic activity index with lime and with Portland cement. The evaluation of the pozzolanic activity by XRD, TG / DTG and compressive strength confirmed the ash reactivity and indicated that the addition of 20% in the composition of cement slurries produces improvement 34% in the mechanical properties of the slurry cured. Cement slurries properties evaluated by rheological measurements, fluid loss, free fluid, slurry sedimentation, thickening time and sonic strength (UCA) were satisfactory and showed the viability of using the sugarcane ash in cement slurries composition for well cementing

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Ethnobiology studies Local Ecological Knowledge (LEK) as well as the use and management of natural resources by local communities in order to understand how the environment is perceived, known and classified by human groups. In fishing communities, LEK adds empirical information about the biology of aquatic species and complements scientific findings, especially when it is difficult to obtain factual information during studies on cetaceans, whose behavior is essentially underwater. Cetaceans (whales and dolphins) are constantly threatened by human activities, especially by accidental capture of small coastal species, as in the case of the estuarine dolphin (Sotalia guianensis), object of this study. Ethnobiological researches in fishing communities are of great importance and can clarify aspects of the biology and conservation of this species. Although extensively studied throughout its distribution range, there are still gaps in the knowledge about S. guianensis. Therefore, fishers local ecological knowledge becomes an additional tool to get and confirm information about S. guianensis. This study evaluated the LEK of artisanal fishers who are daily exposed to local population of S. guianensis, through the use of semistructured interviews (N=116). The interviewed fishers were asked about the biology and popular classification of S. guianensis and about possible interactions between this dolphin and them. The studied communities were located in Tibau do Sul (n=39), Pipa (n=36) and Baía Formosa (n=41), all on the south coast of Rio Grande do Norte, Brazil. The study was based on the assumption that differences in fishers LEK among those communities would be caused by both the variety of fishing environments (lagoon/estuary and ocean) and the intensity of tourism activities. Fishers knowledge is expressive and differed among the studied communities depending on the topic investigated. Fishers correctly reported the habitat, distribution, seasonality and behavioral particularities of S. guianensis. Tourism mainly affected the naming of the species. The study results also suggest that marine fishers have greater knowledge about the species than the estuarine/lagoon ones. Local populations accumulate empirical knowledge according to their environment. Hence, it is important to take into account both empirical knowledge and popular participation in management systems, in order to maintain information sharing among communities

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Avaliou-se a hidroxiapatita com alandronato e hidroxiapatita com colágeno na aceleração da consolidação óssea do rádio de cadelas adultas submetidas à ovariossalpingo-histerectomia (OSH). Utilizaram-se 14 cadelas adultas, distribuídas aleatoriamente em dois grupos: grupo-controle e grupo OSH (submetidas à OSH). Quatro meses após a OSH, as cadelas dos dois grupos foram submetidas à cirurgia para produção de uma falha óssea de 4mm de diâmetro nos terços distal e proximal do rádio. No terço distal do membro direito, foi utilizada a hidroxiapatita com alandronato e, no membro esquerdo, a hidroxiapatita com colágeno; no terço proximal, não se utilizou nenhum biomaterial. Houve retardo na consolidação das falhas ósseas nas cadelas submetidas à OSH comparadas com as não submetidas. A hidroxiapatita com alandronato acelerou o processo de reparação e, em todos os animais dos dois grupos, a densidade óssea foi significativamente maior no terço distal onde foi implantada. Os dois biomateriais apresentaram biocompatibilidade, constatada pela ausência de reação inflamatória ou outra reação indesejável.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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With the increase in cement consumption, it has quickly become one of the inputs most consumed by mankind over the last century. This has caused an increase in CO2 emissions, as cement production releases large quantities of this gas into the atmosphere. Adding this fact to the growing consciousness of environmental preservation, it has led to a search for alternatives to cement to complement its derivatives, in the form of waste materials like the ashes. This research aimed to analyze the properties of mortars in fresh and hardened state with partial replacement of Portland cement by residual algaroba wood ash (CRLA) potteries produced by the state of Rio Grande do Norte. The CRLA was collected and sieved, where part of it was ground and characterized in comparison with that just sifted, being characterized according to its chemical composition, grain size, fineness, density, bulk density and index of pozzolanic activity. It was found that the wood ash does not act as pozzolan, and grinding it has not changed its characteristics compared to those just sifted, not justifying its use. Two traces were adopted for this research: 1:3 (cement: fine sand) and 1:2:8 (cement: hydrated lime: medium sand); both in volume, using as materials the CRLA just sifted, CP II F-32 Portland cement, CH-I hydrated lime, river sand and water from the local utility. For each trace were adopted six percentages of partial replacement of cement for wood ash: 0% (control) 5%, 7%, 10%, 12% and 15%. In the fresh state, the mortars were tested towards their consistency index and mass density. In the hardened state, they were tested towards their tensile strength in bending, compressive strength and tensile adhesion strength, and its mass density in the hardened state. The mortar was also analyzed by scanning electron microscopy and X-ray diffraction. Furthermore, it was classified according to NBR 13281 (2005). The results showed that up to a content of 5% substitution and for both traces, the residual algaroba wood ash can replace Portland cement without compromising the mortars microstructure and its fresh and hardened state

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Concrete is the second most consumed product in the world and the incorporation of the Sugar Bagasse Ash (SBA) into this material can provide solutions for the utilization of by-products from other industries, thus reducing the environmental impact. The general aim of this dissertation focuses on analyzing the mechanical behavior of concrete with addition of SBA from three different species of sugar cane, through tests of consistency, compressive strength, porosity, absorption, voids and Scanning Electron Microscopy (SEM). Were prepared 13 specimens for each specific pattern and level of incorporation of SBA (10%, 20% and 30%) of the three varieties collected, totaling 130 samples of concrete. The trait was employed 1:2:3 (cement: sand: aggregates) in relation to the cement mass with a water / cement ratio of 0.532 and 1% additive Tec 400 Mult also based on the weight of cement. According to the results obtained in this study, it was concluded that the variety of cane sugar, used in the production of the CBC, influenced the mechanical behavior of the resulting concrete. All concrete with addition of SBA, reported a reduction of at least 10% in the properties related to permeability and an increase in the compressive strength of at least 16% compared to standard concrete at 28 days

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The use of sewage sludge as a raw material falls within the waste recycling key in the current process model environmental sustainability .Waste recycling has been consolidated as a sustainable environmentally sound technical solution, and. Despite showing very variable composition and characteristics, sewage sludge, can be considered as a residue with a high recycling potential in the building sector. In this paper the feasibility of using sewage sludge ash was studied in addition to Portland cement mortar in 1:3 mass considered the standard dash. This gray additions were studied in proportions of 5%, 10 %, 15 %, 20 %, 25% and 30% by mass of cement. The methodology was focused on the characterization of materials by physical, chemical , mechanical , environmental and morphological followed by the production of mortar tests ,and finalized by the characterization tests of mortar in the fresh state, through the consistency index, content of entrained air, bulk density and water retention, and in the hardened state by bulk density, water absorption by capillarity capillarity coefficient, compressive strength, tensile strength in bending ,tensile bond strength and microstructural analysis for percentages of 0 to 20%. After comparing with the standard mortar mortars with addition of ash, it is concluded that the ash of sewage sludge did not impair the integrity and properties of mortars with addition, including increasing resistance to compression and tension, being 20% more indicated percentage. Thus, it becomes feasible the addition of sewage sludge ash in Portland cement mortar for the trait studied

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O objetivo do experimento foi avaliar os efeitos do tamanho da partícula do fosfato bicálcico (fina ou granulada) e dos níveis de fósforo total sobre o desempenho de frangos de corte e sobre os teores de cálcio, fósforo e magnésio dos ossos. O delineamento experimental utilizado foi o inteiramente casualizado em esquema fatorial 3x2 com 3 níveis de fósforo total (0,5%; 0,6% e 0,7%) e duas granulometrias de fosfato bicálcico (fina e granulada). Foram utilizados 300 pintos de corte com um dia de idade, machos, da linhagem Cobb, alojados em baterias metálicas em 6 tratamentos com 5 repetições de 10 aves, totalizando 30 gaiolas dispostas em 6 baterias de 5 andares cada. Os resultados demonstraram que o uso do fosfato granulado resultou em melhor desempenho dos animais. Aves alimentadas com o nível de 0,5% de fósforo total apresentaram o pior desempenho, sendo que o nível de 0,6% proporcionou melhor desempenho das aves. As diferentes granulometrias do fosfato, não diferiram estatisticamente quanto a percentagem de matéria mineral, cálcio, fósforo e magnésio nos ossos.

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Every day, water scarcity becomes a more serious problem and, directly affects global society. Studies are directed in order to raise awareness of the rational use of this natural asset that is essential to our survival. Only 0.007% of the water available in the world have easy access and can be consumed by humans, it can be found in rivers, lakes, etc... To better take advantage of the water used in homes and small businesses, reuse projects are often implemented, resulting in savings for customers of water utilities. The reuse projects involve several areas of engineering, like Environmental, Chemical, Electrical and Computer Engineering. The last two are responsible for the control of the process, which aims to make gray water (soapy water), and clear blue water (rain water), ideal for consumption, or for use in watering gardens, flushing, among others applications. Water has several features that should be taken into consideration when it comes to working its reuse. Some of the features are, turbidity, temperature, electrical conductivity and, pH. In this document there is a proposal to control the pH (potential Hydrogen) through a microcontroller, using the fuzzy logic as strategy of control. The controller was developed in the fuzzy toolbox of Matlab®

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)