Produção de tapetes de grama Santo Agostinho submetida a doses de nitrogênio

Nitrogen is the nutrient that provides the greatest turfgrass growth responses and the adequate nitrogen fertilization can provide sod formation in less time and firm to be handled after harvest. This study aimed to evaluate the effect of nitrogen levels in the formation of St. Augustinegrass sod. The experiment was conducted in a sod production farm in Itapetininga, SP. The experimental design was a randomized blocks with four replications. The treatments consisted of five N doses: 0, 150, 300, 450 and 600 kg ha(-1), split into three applications. Increased levels of nitrogen affected the soil cover rate by the St. Augustinegrass reducing the time for sod formation. The leaf N concentration and intensity of green grass were influenced by nitrogen doses, and with the rate of green coverage rate (GCR) of soil, can be used to assist in the recommendation of N doses. Rate of 430 kg ha(-1) of N provided the production of St. Augustinegrass sod resistant the harvest and transport, within ten months.

Incorporação de resíduo de perfuração em matriz cerâmica: estabilização por solidificação

One of the waste generated during the drilling of oil wells are gravel which are impregnated of drilling fluid. This residue consists of highly toxic chemicals, including toxic metals. This study suggests an alternative process to the treatment of this waste, by incorporating it the form of raw material in the ceramic matrix , and by solidification and stabilize the metals present, Aluminum (Al), Iron (Fe), Manganese (Mn) and Zinc (Zn). The raw materials were characterized by the techniques of X ray fluorescence (FRX), X ray diffraction (DRX), laser granulometry (GL), thermogravimetry (TG) and differential thermal analysis (ADT). To evaluate the percentage of gravel effect the environmental and technological properties were obtained from formulations containing 0, 10 and 20 % by weight of gravel in the ceramic matrix. After sintering at temperatures 1080, 1120 and 1160 °C, the samples were tested for water absorption, the linear shrinkage firing, voltage of rupture and solubility. The results obtained showed that the stabilization by solidification, is a viable alternative to safe disposal of waste drilling. Ceramics products can be used in the manufacture of solid bricks

Incorporação de lodo de esgoto na massa cerâmica para fabricação de tijolos maciços: uma alternativa para a disposição final de resíduo

The disposal of sewage sludge is a growing problem face up to management of sanitary sevices. Otherwise, because its making process characteristic, the Ceramic Industry can tolerate the presence of this wastes as raw material. This study has as object to confirm the use of the sewage sluge in the Ceramic Industry like a sustentable alternative for its disposal. Futhermore, this study quests to evaluate the maximum proportion for incorporation of sludge wich result in technically and enviromentally suitable bricks. For found this proportion, the research consisted of (1) making of bricks in full scale, adde up 0%, 5%,10%, 15%, 20%, 25%,30%, 35% e 40% sludge, with size 220x105x45 mm, hand-molded by rammer and baked by industrial kiln; and (2) tecnical and enviromental evaluation of this bricks, according to Brazilian norms. The raw material uses were two distinct clays come from Goianinha/RN and sewage comes from a septic system tank and pumped into tank vehicle, of Natal/RN. The technical evaluation allowed to conclude the addiotion of the sludge brings about signifcant lost of mass and the water absorption grew up according to increase of sludge: every sludge-amended clay bricks absorved more water than control group. Thus, the compressive strength was signicantly decreased because the increase of sludge: bricks with 5% sludge added lost 45% of strength achieved at control group; the bricks made with 10 and 20% lost almost 70% of bigger strength. With up to 25% sludge added to the bricks, the streght decreased over 90%. Concerning heavy metal leaching, the two maximum proportion wich have tecnical approval, it means bricks sludge added with 15 and 20%, can say there is no risk of enviromental contamination using those bricks. This way, in this work context, it can to conclude the maximum proportion atends the technical and enviromental criterion is 20%

Incorporação do resíduo oriundo do beneficiamento de caulim em concreto asfáltico

The municipal district of Equador-RN is located in an area of great amounts of ores, being your main economical activity the extraction and the kaolin improvement. The main originating from environmental problem that activity is the amount of generated residue, about 70% of the extracted kaolin. The residues are simply piled up in lands of the improvement companies, occupying like this a large area and causing impact in the existent flora. When dry, the residues transform powdered and for the action of the wind, they disperse, polluting the air. Being like this, the present work has as objective evaluates the incorporation of the great residue, originating from of the kaolin improvement, in partial substitution of all the employed aggregates in a conventional mixture of asphalt concrete, which was used in the paving of BR101/RN061 - passage between Ponta Negra and Ares. That evaluation was accomplished in three stages. The first refers to the evaluation of the physical, thermal and mineralogical characteristics of the residue with the intention of to classify it and to define your application as aggregate (small and great). The second refers to the physical characterization of the aggregates and of the asphalt material used in the conventional mixture. And the third, to the evaluation of the mixtures containing residue, which were elaborated starting from the conventional mixture with the gradual incorporation of the residue, from 5 to 40%, in substitution to the part of the conventional aggregates, in way to obtain similar particle size curves the one of the conventional mixture. That evaluation was accomplished through the comparison between the volumetric composition, the mechanical behavior and the susceptibility to the humidity of the mixtures containing residue with the one of the conventional mixture, and with the one of the DNIT specifications. The results show that the great residue originating from of the kaolin improvement has grains of the most varied size, being like this, it can substitute part of all the conventional aggregates and of the filler in an asphalt mixture. Besides, your mineralogical composition presented the same present minerals in the composition of conventional aggregates used in paving. The results evaluation of the volumetric composition of the mixtures containing residue indicates that it can use up to 30% of residue in substitution to the conventional aggregates. The evaluation of the mechanical behavior of those mixtures indicates that the residue increment in the studied mixtures caused an increase of the stability and a reduction of the resistance to the traction. The values obtained in the resistance to the traction meet below the minimum value specified by DNIT, but close to the value obtained in the conventional mixture. When taking in consideration the susceptibility of the same ones to the humidity, the results indicate that she can use up to 25% of residue

Análise da adição de resíduo oriundo do tratamento de esgotos em massa cerâmica utilizada para fabricação de telhas

Sludge of Wastewater Treatment Plants (WTPs) disposal is a problem for any municipality, for this reason the amount of sludge production is now a key issue in selecting treatment methods. It is necessary to investigate new applications for this waste type, due to the restrictions imposed by the environmental organs. The raw materials used in the Red Ceramic, are generally very heterogeneous, for this reason, such materials can tolerate the presence of different types of wastes. In Rio Grande do Norte, the roof tiles production corresponds to 60,61% from the total of ceramic units produced. Due to the importance of the ceramic industry of roof tiles for the state, allied to the environmental problem of the sludge disposal, this work had for objective to verify the possibility of the incorporation of sewage sludge in ceramic body used for production of roof tiles. In the research, sludge originating from drying beds of WTP of the Central Campus from UFRN and clays originating from a ceramic industry from Goianinha/RN were used. The raw materials were characterized by techniques of: analysis of particles distribution by diffraction to laser; real density; consistence limits; chemical analysis by X-ray fluorescence; mineralogical analysis by X-ray diffraction; organic matter; and solids content. Five batches of roof tiles were manufactured in the approximate dosages of 2%, 4%, 6%, 8% and 10%. To evaluate the properties of each final product, tests of water absorption, impermeability, bending strength, leachability and solubility were accomplished. The roof tiles manufactured with sludge presented characteristics similar to the roof tiles without sludge in relation to the environmental risk. The results showed that it is possible to use approximately up to 4% of sludge in ceramic bodies for production of roof tiles. However, it is observed that the high amount of organic matter (71%) present in the sludge is shown as factor that limits the sludge incorporation in ceramic bodies, worsening the quality of the roof tiles. It is necessary the use of mixtures of different raw materials under point of view of the granulometry and of the other chemical and mineralogical properties for the obtaining of a satisfactory mass to the production of ceramic roof tiles

Caracterização do comportamento geotécnico de mistura de resíduo de pneus e solo laterítico

A technological alternative for the correct disposal of tires is the use in the construction of embankment with soil and shredded tires. The use of waste tires in tropical soils requires prior knowledge of the properties and limitations of these materials. In this work, the results of an experimental program was devised to characterize the behavior of mixtures of waste tires and a lateritic soil. The residue used in this study is classified as tire buffings with an average size of 1.4 mm. The laboratory program included testing of particle size analysis, Atterberg limits, compaction, direct shear tests, permeability and confined compression tests with pure soil, pure tire and the mixtures. Proportions of 0% (pure soil), 10%, 20%, 40%, 50 % and 100% (pure tire) by weight were used. For the confining stress levels used in the study, the presence of tire residue provided a considerable increase in shear strength of the mixture. The maximum shear strength was obtained for a residue content of 40% by weight. Permeability tests on samples of waste under a confining stress of 100 kPa showed that the permeability increases significantly with increasing residue content until a residue content of 20%. The increase in permeability after that value showed to be negligible. Confined compression tests showed that the soil mixed with tire residue becomes more compressible than the pure soil. The secant constrained modulus (Msec) for the same vertical stress decreases with increasing percentage of residue.

Optical Behavior of Conjugated Pt-Containing Polymetallaynes Exposed to Gamma-Ray Radiation Doses

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Structural Changes of Conjugated Pt-Containing Polymetallaynes Exposed to Gamma Ray Radiation Doses

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Administração repetida de baixas doses de reserpina: um possível modelo para o estudo de déficits cognitivos e motores associados à Doença de Parkinson

Parkinson's disease (PD) is one of the most common neurodegenerative brain disorders and is characterized primarily by a progressive degeneration of dopaminergic neurons nigroestriatais. The main symptoms of this disease are motor alterations (bradykinesia, rigidity, tremor at rest), which can be highly disabling in advanced stages of the condition. However, there are symptomatic manifestations other than motor impairment, such as changes in cognition, mood and sensory systems. Animal models that attempt to mimic clinical features of PD have been used to understand the behavioral and neural mechanisms underlying neurophysiological disturbance of this disease. However, most models promote an intense and immediate motor impairment, consistent with advanced stages of the disease, invalidating these studies for the evaluation of its progressive nature. The administration of reserpine (a monoamine depletor) in rodents has been considered an animal model for studying PD. Recently we found that reserpine (in doses lower than those usually employed to produce the motor symptoms) promotes a memory deficit in an aversive discrimination task, without changing the motor activity. It was suggested that the administration of this drug in low doses can be useful for the study of memory deficits found in PD. Corroborating this data, in another study, acute subcutaneous administration of reserpine, while preserving motor function, led to changes in emotional context-related (but not neutral) memory tasks. The goal of this research was to study the cognitive and motor deficits in rats repeatedly treated with low doses of reserpine, as a possible model that simulates the progressive nature of the PD. For this purpose, 5-month-old male Wistar rats were submitted to a repeated treatment with vehicle or different doses of reserpine on alternate days. Cognitive and motor parameters and possible changes in neuronal function were evaluated during treatment. The main findings were: repeated administration of 0.1 mg / kg of reserpine in rats is able to induce the gradual appearance of motor signs compatible with progressive features found in patients with PD; an increase in striatal levels of oxidative stress and changes in the concentrations of glutamate in the striatum were observed five days after the end of treatment; in animals repeatedly-treated with 0. 1 mg/kg, cognitive deficits were observed only after the onset of motor symptoms, but not prior to the onset of these symptoms; 0.2 mg / kg reserpine repeated treatment has jeopardized the cognitive assessment due to the presence of severe motor deficits. Thus, we suggest that the protocol of treatment with reserpine used in this work is a viable alternative for studies of the progressive appearance of parkinsonian signs in rats, especially concerning motor symptoms. As for the cognitive symptoms, we suggest that more studies are needed, possibly using other behavioral models, and / or changing the treatment regimen

Déficits de memória induzidos por baixas doses de reserpina em ratos: possível relação com prejuízos no processamento emocional na Doença de Parkinson

We have recently verified that the monoamine depleting drug reserpine at doses that do not modify motor function - impairs memory in a rodent model of aversive discrimination. In this study, the effects of reserpine (0.1-0.5 mg/kg) on the performance of rats in object recognition, spatial working memory (spontaneous alternation) and emotional memory (contextual freezing conditioning) tasks were investigated. While object recognition and spontaneous alternation behavior were not affected by reserpine treatment, contextual fear conditioning was impaired. Together with previous studies, these results suggest that mild monoamine depletion would preferentially induce deficits in tasks involved with emotional contexts. Possible relationships with cognitive and emotional processing deficits in Parkinson disease are discussed

Síntese, caracterização e aplicação do MCM-41 e A1-MCM-41 na pirólise do resíduo atmosférico de petróleo

In present work, mesoporous materials of the M41S family were synthesized, which were discovered in the early 90s by researchers from Mobil Oil Corporation, thus allowing new perspectives in the field of catalysis. One of the most important members of this family is the MCM-41, which has a hexagonal array of mesopores with pore diameters ranging from 2 to 10 nm and a high surface area, enabling it to become very promising for the use as a catalyst in the refining of oil in the catalytic cracking process, since the mesopores facilitate the access of large hydrocarbon molecules, thereby increasing the production of light products, that are in high demand in the market. The addition of aluminum in the structure of MCM-41 increases the acidity of the material, making it more beneficial for application in the petrochemical industry. The mesoporous materials MCM-41 and Al-MCM-41 (ratio Si / Al = 50) were synthesized through the hydrothermal method, starting with silica gel, NaOH and distilled water. CTMABr was used as template, for structural guiding. In Al-MCM-41 the same reactants were used, with the adding of pseudoboehmite (as a source of aluminum) in the synthesis gel. The syntheses were carried out over a period of four days with a daily adjustment of pH. The optimum conditions of calcination for the removal of the organic template (CTMABr) were discovered through TG / DTG and also through analysis by XRD, FTIR and Nitrogen Adsorption. It was found that both the method of hydrothermal synthesis and calcination conditions of the studies based on TG were promising for the production of mesoporous materials with a high degree of hexagonal array. The acidic properties of the materials were determined by desorption of n-butylamine via thermogravimetry. One proved that the addition of aluminum in the structure of MCM-41 promoted an increase in the acidity of the catalyst. To check the catalytic activity of these materials, a sample of Atmospheric Residue (RAT) that is derived from atmospheric distillation of oil from the Pole of Guamaré- RN was used. This sample was previously characterized by various techniques such as Thermogravimetry, FTIR and XRF, where through thermal analysis of a comparative study between the thermal degradation of the RAT, the RAT pyrolysis + MCM-41 and RAT + Al- MCM-41. It was found that the Al-MCM-41 was most satisfactory in the promotion of a catalytic effect on the pyrolysis of the RAT, as the cracking of heavy products in the waste occurred at temperatures lower than those observed for the pyrolysis with MCM-41, and thereby also decreasing the energy of activation for the process and increasing the rates of conversion of residue into lighter products

Coberturas vegetais, doses de nitrogênio e inoculação de sementes com Azospirillum brasilense em arroz de terras altas no sistema plantio direto

O arroz é importante fonte de energia e proteínas para a população mundial, principalmente na Ásia e Oceania. No Brasil, juntamente com o feijão, constitui a base da alimentação. Tecnologias sustentáveis que reduzam custos da produção e aumentem a produtividade do arroz podem garantir seu suprimento em períodos de alta demanda. O objetivo deste trabalho foi avaliar diferentes coberturas vegetais antecessoras (milheto [Pennisetum americanum], crotalária [Crotalaria juncea], guandu [Cajanus cajan], braquiária [Brachiaria ruziziensis], milheto + crotalária e milheto + guandu), doses de nitrogênio (N) em cobertura (0, 40, 80 e 120 kg ha-1) e o efeito da inoculação de sementes com Azospirillum brasilense no arroz de terras altas em sistema plantio direto no desenvolvimento e na produtividade. Utilizou-se o delineamento experimental em blocos casualizados em esquema fatorial 6x4x2 com quatro repetições. O estudo foi desenvolvido em um Latossolo Vermelho, em Selvíria, Estado do Mato Grosso do Sul, Brasil, em 2011/2012. O cultivo do guandu antecedendo o arroz proporcionou maior produtividade do arroz somente em comparação a B. ruziziensi. A produtividade do arroz em função das doses de N em cobertura se ajustou a uma função quadrática. Não houve influência da inoculação de sementes com A. brasilense sobre a produtividade do arroz, porém houve interação entre a inoculação e as coberturas vegetais sobre o teor de N foliar, número de panículas por m², matéria seca de plantas de arroz e a massa de cem grãos.

Preparo do solo e doses de nitrogênio em cobertura em arroz de terras altas

As influências do sistema de preparo do solo e da adubação nitrogenada não estão bem definidas para o arroz de terras altas. Assim, com o objetivo de avaliar os componentes da produtividade e o rendimento industrial do arroz de terras altas irrigado por aspersão, em função do preparo do solo e de doses de nitrogênio em cobertura, conduziu-se o experimento em condições de campo, em Selvíria (MS), por duas safras consecutivas: 2003/2004 (cultivar BRS Talento) e 2004/2005 (cultivar IAC 202). Adotou-se o delineamento em blocos casualizados, constituído pela combinação de três manejos de solo (grade aradora + grade niveladora, escarificador + grade niveladora e plantio direto) e seis doses de N em cobertura (0 kg ha-1, 25 kg ha-1, 50 kg ha-1, 75 kg ha-1, 100 kg ha-1 e 125 kg ha-1), com quatro repetições. Avaliou-se a concentração de N na folha, altura de plantas, componentes de produção, produtividade e o rendimento industrial dos grãos. O preparo do solo com escarificador + grade niveladora propiciou a obtenção de maiores produtividades das duas cultivares, enquanto a adubação nitrogenada em cobertura interferiu apenas na produtividade da cultivar IAC 202, sem afetar o rendimento industrial de grãos.

Integração agricultura-pecuária em plantio direto: produção de forragem e resíduo de palha após pastejo

O objetivo deste trabalho foi verificar, no sistema integração agricultura-pecuária, a possibilidade de utilizar uma cultura para pastejo cujos resíduos permitam produção de palha suficiente para a manutenção do plantio direto, bem como avaliar a produção da forrageira e do resíduo em diferentes distâncias em relação ao centro do pivô, em três épocas, e o desempenho econômico do sistema. Avaliaram-se o impacto do pastejo rotacionado de sorgo forrageiro em plantio direto, sob irrigação em um pivô central de 75 ha, sobre a produção de matéria seca do sorgo forrageiro, a quantidade de resíduos, o custo de produção e o ganho de peso animal. O ensaio foi conduzido num Latossolo Vermelho Distrófico. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas, com quatro tratamentos principais: locais de amostragem em diferentes distâncias em relação ao centro do pivô; três tratamentos secundários (ciclos de pastejos) e sete repetições (sete piquetes de 9,37 ha para pastejo, dispostos na forma de pizza). Os resultados permitiram concluir que: a produção do sorgo forrageiro foi suficiente para permitir um ganho 621 kg ha-1 de peso vivo e a quantidade de resíduos de sorgo após o pastejo foi suficiente para suprir o aporte anual de matéria seca de palha necessária para a manutenção do plantio direto; a área, após os pastejos, continuou passível de ser explorada no sistema de plantio direto, e o sistema pesquisado mostrou-se técnica e economicamente viável.

Caracterização de resíduo sólido formado em biodiesel de sebo bovino

Biodiesel production has increased over the last decade because of the benefits associated with this fuel, including renewability, domestic feedstock, lower toxicity, and biodegradability. From 2008, the use of beef tallow as a feedstock for biodiesel production in Brazil has increased in significance, representing the second largest source of biodiesel, after soybeans. However, the performance of biodiesel in cold weather conditions is worse than diesel because of deposition of insoluble at low temperatures, accelerating the plugging of fuel filters and injectors of the vehicle engine. Studies have been conducted on beef tallow biodiesel, mostly related to the properties of thermal and oxidative stability. However, few studies have described the nature of the precipitate formed and its influence on product quality. Research suggests that the cause of deposition is related to the nature of saturated esters and monoacylglycerols as inducing agents. This study monitored the levels of mono-, diand triacylglycerols, the oxidation stability and the cold filter plugging point (CFPP) in beef tallow biodiesel samples from two commercial producers in Brazil for a period of twelve months. Filtered precipitates were analyzed by comparative techniques of GCFID, HPLC-UV/VIS, HPLC-MS-IT-TOF and TG to verify the nature, using monopalmitin and monostearin as reference standards. The formation of precipitate reduced the levels of monoacylglycerols in the beef tallow biodiesel. GC-FID and LCMS- IT-TOF results confirmed the nature of the deposit as saturated monoacylglycerols, predominantly monostearin and monopalmitin as the second major component. Moreover the TG analysis of the residue indicated similar thermal decomposition of the reference standards. The precipitate did not affect the oxidation stability of beef tallow biodiesel and the CFPP characteristic of blends up B60. However, the presence of iron reduced significantly the oxidation stability of biodiesel