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Imagem componente do jogo “MathJong (http://www.loa.sead.ufscar.br/MathJong.php)” desenvolvido pela equipe do Laboratório de Objetos de Aprendizagem da Universidade Federal de São Carlos (LOA/UFSCar).

Botão amarelo

Imagem componente do jogo “MathJong (http://www.loa.sead.ufscar.br/MathJong.php)” desenvolvido pela equipe do Laboratório de Objetos de Aprendizagem da Universidade Federal de São Carlos (LOA/UFSCar).

Adição de subprodutos da cinza da casca de café (coffea canephora) em massa cerâmica para porcelanato

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

Influência da adição de cinza do bagaço de cana calcinada em sistemas de pastas para cimentação de poços petrolíferos

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

Morfologia e quantificação da microbiota intestinal do curimbatá (Prochilodus lineatus) e do cascudo cinza (Pterygoplichthys anisitsi) cultivados em cativeiro

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo do comportamento no estado fresco e endurecido do concreto com incorporação de resíduo de corte de botão

This works aims at investigating the effects of adding waste from RCBP-polyester button manufacturing to Portland cement concrete, particularly regarding its consistency and mechanic strength. The RCBP used came from a button factory located in Parnamirim, RN, Brazil. The waste was added to the concrete on different ratios: 5 %, 10 %, 15 % and 20 % of the total cement mass. A sample of concrete without the RCBP was used as reference, 1:1,33:2,45:0,50. For the mechanic strength test four samples were tested with different ages (3, 7 and 28 days old) and mixtures. Furthermore, a Slump Test was also conducted in order to verify the concrete s consistency. A tendency to a reduction in the compression resistance was noticed for all samples. For the samples with 5 % and 10 %, there was also an increase in the traction resistance during inflexion, regarding the reference concrete. In the microstructural analysis, the RBCP was observed to show an irregular and porous surface, thus explaining the consistency decrease

Estabilização de um Solo com Cimento e Cinza de Lodo Para Uso em Pavimentos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Análise de Argamassas Com Substituição Parcial do Cimento Portland Por Cinza Residual de Lenha de Algaroba

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

Análise do Comportamento Mecânico de Concretos Produzidos com Incorporação de Cinza do Bagaço da Cana-de-Açúcar de Variedades SP911049, RB92579 E SP816949

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

Estudo da viabilidade da utilização de cinza de lodo de esgoto como adição em argamassa de cimento Portland

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

Sistema automatizado para o aproveitamento de água cinza e azul, com controle de PH utilizando lógica fuzzy

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®

Crescimento, produção e qualidade de frutos da bananeira 'Figo cinza', em Botucatu-SP

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

Efeito da introdução de resíduo de cinza de forno cerâmico em massa para cerâmica estrutural

The red ceramics and structural ceramics, as they are known, include ceramic materials made by blocks of seals and structures, bricks, tiles, smail flagstones manacles, rustic floors and ornamental materials. Their fabrication uses raw material such as clay and clay sites, with some content of impurity. It has good durability and mechanical strength to compression, low cost, making it one of the mainly used materials in civil engineering. The incorporation of many industrial activities residue to ceramic products is a technological alternative for reducing the environmental impact caused by its carefree disposal. This incorporation can promote chemical change and inertness of metals from residue, by fixation in the glassy phase of ceramic during the burning stage. The main aim of this project is to study the technical feasibility of the addition of ceramic oven ash into formulations of mass for structural ceramics. In this project two kinds of clay (plastic and non-plastic) were used, as well as the ash from firewood used in the process of burning of structural ceramics. A group of experiments was outlined, which permitted the evaluation of the influence of the burning cycle in different temperatures of the ash content in formulations for ceramic blocks through technological properties, mechanical behavior and microstructure. Five samples were processed of each one of the masses of plastic and non-plastic clay without addition of ash and with addition of ash on the percentages of 10 % and 20 %, for temperatures of 850 °C, 950 °C, 1050 °C and 1150 °C, obtained through sinterization process. Among the studied compositions, the one which presented best performance was the mass of clay with 10 % of ash, at temperature of 1150 °C, with the smallest absorption of water, the smallest apparent porosity, specific apparent mass a bit over the others and greatest mechanical resistance to flexion. The composition made confirmed the technical feasibility of the use of ash in the mass for structural ceramics with maintenance of its necessary characteristics for its purposes

Obtenção de placas cerâmico a partir de formulações de massas triaxiais de resíduos de caulim, chamote de telha e cinza vegetal

The production of red ceramic is an industrial activity that causes an intense impact. The manufacture of its products considerably increases the demand for natural resources, mainly with the extraction of raw material. The ceramic material produced generates waste, such as ash firewood and chamote. The residue from the beneficiation of kaolin is deposited in a poor, degrades the environment and contaminate water sources and soil, constituting in this manner, ecological disasters. The main objective of this work is to develop the formulation of a ceramic product consisting solely of industrial solid wastes, from ceramic tiles, (chamote) residue of kaolin and ash firewood. It is assumed that this product made in the laboratory can be used in coatings, wall and floor. The aim is to facilitate the replacement of the raw material of original composition of a ceramic body, for waste, while the process of production equal to the conventionally used, so that the properties of the product are reproduced. This work is characterized waste as its chemical composition, analysis of particle size, X-ray diffraction and thermal behavior. Several formulations were studied. The mass of waste was prepared by dry process, pressed to 25 MPa, and then burned in muffle type oven to 850, 950, 1050 and 1150 °C. The results showed that it is technically possible to produce porous tiles only with waste. It was found that the formulations of bodies play a key role in the properties of the final product, as well as the sintering temperature and heating rates. RN in the waste of kaolin is estimated at 15,000 t/month, about 3,000 gray t/month and chamote with 10 million pieces/month damaged. The presence of carbonates of calcium and magnesium at 1050 ° C results in an appropriate porosity and mechanical strength. The formulation M3JE, composed of 69% waste of kaolin, 7.7% and 23.3% of chamote of gray, became suitable for porous materials with the strength and absorption within the level of national and international standards

Aproveitamento de resíduos de cinza da cana de açúcar em massas cerâmicas

This study aimed to investigate the use of cane sugar ashes from small-scale stills of Eunápolis region, state of Bahia, in pottery mass that can be developed as porcelain stoneware. Bahia is the second largest producer of rum distillery in Brazil. In the production of rum is produced residue called bagasse, which is used to generate electricity in Power plants and in the distillery itself, generating ashes as residue, which is played in nature, causing environmental damage. We studied 5 (five) formulations of 0% 10% 20%, 30% and 40% by weight of the ash, without ignition and 3 (three) formulations of 10%, 20% and 30% with gray ash temperature of 1250ºC. The formulation at 0% by weight of ash was used for a comparison between the traditional mass of porcelain stoneware and the masses with the addition of ash calcined, replacing feldspar. The percentage by weight of kaolin and of Clay was kept the same, 30%, and all raw materials were derived from the state of Bahia. The samples were made in uniaxial array with dimensions of (60 x 20 x 5) mm and compressed to a pressure of 45 MPa. Assays were performed to characterize the raw by X-ray fluorescence, X-ray diffraction, ATD and ATG and Dilatometric analysis. The samples were sintered at temperatures of 1100°C, 1150°C, 1200°C and 1250°C, for the specimens with the ashes without ash and 1150° C and 1200° C for specimens with the gray level of calcined 60 minutes. and then we made a cooling ramp with the same rate of warming until reach ambient temperature. The sintered bodies were characterized by water absorption, porosity, linear shrinkage, bending strength and XRD of the fracture surface and the results analyzed. It was proven, after results of tests performed, that it is possible to use the ash residue of sugar cane bagasse on ceramic coating with the addition of up to 10% wt of the residue ash