988 resultados para 1050°
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
The aim was to study the efficiency of electrical conductivity test in evaluating the quality of castor seeds. Emergence of seedlings was evaluated in the field, with five seed lots of cv. AL Guarany 2002. The seeds were submitted to the following tests: germination; first count of germination; accelerated aging (45 degrees C by 24 to 100% UR), emergence of seedlings in the field, rate of speed of development of seedlings and electrical conductivity, testing the periods (2, 4, 6, 8 and 24 hours) and the number of seeds (25,50 and 75) in 75ml of distilled water conditioning to 25 degrees C. A completely randomized design was used. The averages were compared by the Tukey test at 5%. The mean laboratory and field test data were correlated. Electrical conductivity test for 4 hours with 25 seeds and 6 hours with 50 seeds, and the rate of speed emergency proved efficient in the selection of lots vigor by providing information equivalent to the emergence of seedlings in the field.
Resumo:
Objetivou-se avaliar o consumo de nutrientes e o desempenho de novilhas Nelore alimentadas com dietas contendo cana-de-açúcar in natura (CN) ou hidrolisada (CH) com 0,5% de Ca(OH)2 armazenada por 24, 48 e 72 horas. Foram utilizadas 24 novilhas com nove meses de idade e 119,6±8,1kg de peso corporal inicial. O delineamento experimental utilizado foi o inteiramente casualisado com quatro tratamentos e seis repetições. O consumo de matéria seca foi reduzido em 29% pela adição de Ca(OH)2, não sendo alterado pelo período de armazenamento da CH. O consumo de cálcio foi incrementado (P<0,05) pela utilização de CH nas dietas, mantendo níveis de ingestão aceitáveis. Novilhas alimentadas com CH armazenada por 24, 48 e 72 horas apresentaram, respectivamente, ganhos de peso 41, 30 e 35% inferior (P<0,05) àquelas alimentadas com CN. O tratamento da cana-de-açúcar com Ca(OH)2 não é recomendado para alimentação de novilhas Nelore, em virtude de limitar a ingestão e reduzir o ganho de peso.
Resumo:
O objetivo neste trabalho foi avaliar economicamente o uso da restrição alimentar qualitativa para suínos machos castrados em terminação sobre o desempenho e as características de carcaça de 60 animais. Dez suínos foram abatidos no início da fase experimental (89,0 ± 4,2 kg) e os demais, alimentados com rações contendo cinco níveis de restrição nutricional qualitativa (0, 5, 10, 15 e 20%), obtidas pela inclusão de casca de arroz finamente moída, até o final do experimento (127,8 ± 2,9 kg). Foram calculados os custos com alimentação durante o período experimental (R$alimento) e estimados os valores de receita bruta de cada carcaça de animais abatidos aos 128 kg (RBsuíno128kg) ou no início do experimento (RBmédia_suíno89kg). A partir destes três dados, foi calculado o resultado líquido (RL) do uso das dietas experimentais (RL = RBsuíno128kg - RBmédia_suíno89kg - R$alimento). Também foram analisadas as variações mensais dos preços do milho, do farelo de soja e do suíno, sendo determinado o preço do milho como o fator de maior impacto sobre a lucratividade do uso da restrição qualitativa. A equação de predição da probabilidade de aumento linear do resultado líquido pelo uso da restrição qualitativa foi determinada em função dos diferentes preços do milho - PM (valor de P RL = 0,392 - 0,625PM, R² = 0,73). Efeito significativo foi observado para preços do milho de cerca de quatro vezes ou mais acima do custo da casca de arroz. Assim, conclui-se que a viabilidade do uso da restrição qualitativa, até o nível de 20%, depende do cenário econômico, mas sobretudo do preço do milho, o principal ingrediente substituído nas rações ao empregar-se a restrição qualitativa, e de sua relação com o custo do resíduo utilizado para diluição energética.
Resumo:
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
Resumo:
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
Resumo:
The production of roof tiles in the state of Rio Grande do Norte accounts for around 60% of the total of ceramic pieces produced. There is a need for investment to improve quality and productivity, thereby promoting technological innovations. Accordingly, the aim of this study is to determine the effect of kaolin, potassium feldspar and quartz in two standard formulations, as well as the effect of sintering temperature on the technological properties of linear firing shrinkage, water absorption and bending rupture stress, by fitting the statistical model and using multiple linear regression to assess the relationship between technological properties and independent variables. The raw materials were characterized using the following techniques: X-ray fluorescence (XRF), X-ray diffraction (XRF), rational analysis (RA), differential thermal analysis (DTA) and granulometric analysis (GA). The test specimens were compacted by uniaxial pressure (25 MPa), dried in a stove at 110 ºC for 24 hours and sinterized at 850 ºC, 950 ºC and 1050 ºC and held isothermal for 30 minutes. The results obtained indicate that the addition of kaolin to two standard formulations (M and R) promoted a reduction in water absorption values and an increase in bending rupture stress values. The sintering temperatures for group M that resulted in the lowest linear firing shrinkage and water absorption values were 850 ºC and 950 ºC, respectively, and the highest bending rupture stress values were reached at a temperature of 950 ºC. In the case of group R, the sintering temperature that obtained the lowest water absorption and linear firing shrinkage values was 850 ºC, and the highest bending rupture stress values were attained at a temperature of 1050 ºC. This work explains the statistical approach used to fit the model that describes the relationship between the technological properties and percentage of kaolin, quartz and feldspar, as well as the models that enable predictions, provided that the lower and upper limits of the percentage of clay minerals, flux and quartz used in this study are respected. Statistica 6 software was used and results were obtained by stepwise forward regression
Resumo:
This work has for objective study compared the characteristics and technological properties of ceramic bodies from the region of Seridó-RN. The region under study has identified 23 cities where they were 80 ceramics industries. To define the universe of search, there was a survey of pottery that are part of APL Seridó next to the IEL. The characteristics and operating conditions of ceramics industries of the region were identified through a socio-economic questionnaire applied locally, which addressed issues such as: profiles of companies, production process etc. The analysis of information collected from 24 companies identified in seven cities shows that the vast majority of industries is small, with family structure, obsolete equipment and labo, little qualified. Most of the pottery works with low technical knowledge, poor control of the production process and product technology. The raw collected were submitted to analysis of X ray diffraction, chemical composition, termical analysis, particle size distribution and plasticity. Then were produced five formulations and made by uniaxial pressure at 25 MPa for firing in temperatures varying from 850 to 1050 °C. The firing technological properties evaluated were: mass loss to fire, lineal shrinkage, apparent density, apparent porosity, water absorption and flexural strength (3 points). The results indicated that the raw materials from the region have significant similarities in the composition chemical and mineralogical. Furthermore, it indicates the possibility of the use of cycles of firing faster and efficient than the current, limited to some clay mass burning of certain conditions
Resumo:
The sector of civil construction is strongly related to the red ceramic industry. This sector uses clay as raw material for manufacturing of various products such as ceramic plates. In this study, two types of clay called clay 1 and clay 2 were collected on deposit in Ielmo Marinho city (RN) and then characterized by thermogravimetric analysis (TG/DTG), differential thermal analysis (DTA), X-ray diffraction (XRD), X-ray fluorescence (XRF), rational analysis and particle size distribution and dilatometric analyses. Ceramic plates were manufactured by uniaxial pressing and by extrusion. The plates obtained by pressing were produced from the four formulations called 1, 2, 3 and 4, which presented, respectively, the following proportions by mass: 66.5% clay 1 and 33.5% clay 2, 50% clay 1 and 50% clay 2, 33.5% clay 1 and 66.5% clay 2, 25% clay 1 and 75% clay 2. After firing at 850, 950 and 1050 °C with heating rate of 10 °C/min and soaking time of 30 minutes, the following technological properties were determined: linear firing shrinkage, water absorption, apparent porosity, apparent specific mass and tensile strength (3 points). The formulation containing 25% clay 1 produced plates with most satisfactory results of water absorption and mechanical resistance, because of that it was chosen for manufacturing plates by extrusion. A single firing cycle was established for these plates, which took place as follow: heating rate of 2 °C/min up to 600 ºC with soaking time of 60 minutes, followed by heating using the same rate up to 1050 ºC with soaking time of 30 minutes. After this cycle, the same technological properties investigated in the plates obtained by pressing were determined. The results indicate (according to NRB 13818/1997) that the plates obtained by pressing from the mixture containing 25 wt% clay 1, after firing at 1050 °C, reach the specifications for semi-porous coating (BIIb). On the other hand, the plates obtained by extrusion were classified as semi-stoneware (group AIIa)
Resumo:
In this work is the addition of a metallic ion, of the metal Manganese, in a clay of Rio Grande do Norte state for structural ceramics use, the objective this study was to assess the evolution of ceramic properties. The clay was characterized by Chemical and Thermal analysis and Xray difraction. The metallic ion was added in the clay as aqueous solutions at concentrations of 100, 150 and 200 mg / L. The molded by extrusion and the burned were temperatures at 850, 950, 1050 and 1150 º C. Was made Chemical Analysis and investigated the following parameters environmental and ceramic: Solubility, Colour, Linear Retraction (%), Water Absorption (%), Gresification Curves, Apparent Porosity (%), Apparent Specific Mass (g/cm3) and Flexion Rupture Module (kgf/cm2). The results showed that increasing the concentration of metallic ion, properties such as Apparent Porosity (%), Water Absorption (%) decreases and the Flexion Rupture Module (kgf/cm2) increases with increasing temperature independent of the concentration of the ion. The gresification curves showed that the optimum firing temperatures were in the range between 950 and 1050 ° C. The evaluation of the properties showed that the ceramic material can be studied its use in solid brick and ceramic materials with structural function of filling. The results of solubility showed that the addition of ion offers no risk to the environment
Resumo:
As part of a larger study evaluating several silvicultural techniques for restoring tropical moist forests on abandoned agricultural lands in southeastern Brazil, direct seeding with five early-successional Atlantic forest species was tested at three degraded sites, characterized by different soil types and land-use histories, within the Environmental Protection Area at Botucatu, SP. The species used in this study were Chorisia speciosa, Croton floribundus, Enterolobium contorstisiliquum, Mimosa scabrella, and Schizolobium parahyba. Scarified seeds of each of these species were sown in prepared seed spots in replicated, 0.25 ha mixed-species plots at an initial espacement of 1 m x 1 m at each site. of the five species planted, only two, Enterolobium and Schizolobium, showed good seed germination, seedling survival, and early growth rates, averaging 4.1-4.6 cm stem diameter and 1.5-1.7 m height growth during the first 2 years after sowing. These two species constituted 88-100% of the total stand density, which ranged from 1050 to 1790 stems ha(-1) at 2 years. Despite the poor performance of the other species tested, we observed that the natural regeneration of native forest species originating from remnant forests in the general vicinity of our study sites was significantly greater within the direct-seeded plots than in unplanted control plots that were protected from fire and other disturbances. Published by Elsevier B.V. B.V.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
This paper describes the effect of nitrogen Plasma Immersion Ion Implantation (PIII) on chemical structure, refraction index and surface hardness of plasma-polymerized hexamethyldisilazane (PPHMDSN) thin films. Firstly, polymeric films were deposited at 13.56 MHz radiofrequency (RF) Plasma Enhanced Chemical Vapour Deposition (PECVD) and then, were treated by nitrogen PIII from 15 to 60 min. Fourier Transformed Infrared (FTIR) spectroscopy was employed to analyse the molecular structure of the samples, and it revealed that vibrations modes at 3350 cm(-1), 2960 cm(-1), 1650 cm(-1), 1250 cm(-1) and 1050 cm(-1) were altered by nitrogen PIII. Visible-ultraviolet (vis-UV) spectroscopy was used to evaluate film refractive index and the results showed a slight increase from 1.6 to 1.8 following the implantation time. Nanoindentation revealed a surface hardness rise from 0.5 to 2.3 GPa as PIII treatment time increased. These results indicate nitrogen PIII is very promising in improving optical and mechanical properties of PPHMDSN films.