888 resultados para Ondas produzidas pelo vento


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The vehicles are the main mobile sources of carbon monoxide (CO) and unburned hydrocarbons (HC) released into the atmosphere. In the last years the increment of the fleet of vehicles in the municipal district of Natal-RN it is contributing to the increase of the emissions of those pollutants. The study consisted of a statistical analysis of the emissions of CO and HC of a composed sample for 384 vehicles with mechanization Gasoline/CNG or Alcohol/Gasoline/CNG of the municipal district of Natal-RN. The tests were accomplished in vehicles submitted to Vehicular Safety's Inspection, in the facilities of INSPETRANS, Organism of Vehicular Inspection. An partial gases analyzer allowed to measure, for each vehicle, the levels of CO and HC in two conditions of rotation of the motor (900 and 2500 rpm). The statistical analysis accomplished through the STATISTICA software revealed a sensitive reduction in the efficiency of the converters catalytic after 6 years of use with emission average it is of 0,78% of CO and 156 (ppm) of HC, Which represents approximately 4 (four) times the amount of CO and the double of HC in comparison with the newest vehicles. The result of a Student s t-test, suggests strongly that the average of the emissions of HC (152 ppm), at 900 rpm, is 40% larger than at 2500 rpm, for the motor without load. This result reveals that the efficiency of the catalytic conversion is limited kinetically in low engine speeds. The Study also ends that when comparing the emissions of CO and HC considering the influence of the fuels, it was verified that although the emissions of CO starting from CNG are 62% smaller than arising from the gasoline, there are not significant differences among the emissions of HC originating from of CNG and of the gasoline. In synthesis, the results place the current criteria of vehicular inspection, for exhaust gases, in doubt, leading the creation of emission limits of pollutant more rigorous, because the efficiency of the converters catalytic is sensibly reduced starting from 6 years of use. It is also raised the possibility of modifications in the test conditions adopted by the current norms, specifically in the speed engine, have seen that in the condition without load the largest emission indexes were registered in slow march. That fact that allows to suggest the dismissal of the tests in high speed engine, reducing the time of inspection in half and generating economy of fuel

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Foram avaliados os perfis de distribuição volumétrica das pontas de pulverização de jato plano Extended Range XR 8004, Teejet TP 8004 e TwinJet TJ60-8004, em mesa de teste construída segundo a norma ISO 5.682-1:1996, sendo as pontas de pulverização posicionadas a 30, 40 e 50 cm de altura da mesa coletora, submetidas à pressão de 200 e 300 kPa, e posicionadas com ângulos de 30 e 45º nos sentidos horário e anti-horário e na posição vertical (0º). As pontas TJ60-8004 foram analisadas nas mesmas alturas, porém somente na posição vertical. Avaliaram-se 10 unidades de cada tipo de ponta, instaladas isoladamente na mesa. A distribuição média do volume pulverizado, coletado nas provetas, foi inserida em programa computacional, que permitiu a simulação do perfil de distribuição de uma barra pulverizadora com 24 bicos, em espaçamentos variáveis, obtendo-se ao final o coeficiente de variação, o desvio-padrão e a média do volume. Os resultados mostraram que a uniformidade de distribuição é menos influenciada pela variação da altura da barra quando o espaçamento entre bicos é reduzido e que há necessidade de adequação do espaçamento quando se utiliza ângulo na barra pulverizadora.

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Objetivou-se com este trabalho avaliar o efeito de pontas de pulverização, pressão e intensidade do vento na deriva gerada em aplicações simuladas de herbicidas aplicados em pré-emergência. Os modelos de pontas de pulverização e as respectivas pressões testadas foram: SF 11002 (207 e 310 kPa), JA-2 (345 e 655 kPa) e AVI 11002 (207 e 414 kPa). As aplicações foram realizadas em dois períodos, em dias com condições de velocidade de vento distintas, em uma área de 1.200 m², localizada na Fazenda Experimental da FCA/UNESP. Um pulverizador com barra de 12 m, 24 bicos e tanque de 600 L foi utilizado nas aplicações. A calda de aplicação foi composta por água e o corante alimentício FDC-1 foi usado como traçador. A deriva foi amostrada por coletores ativos fixados sobre a barra de pulverização. As velocidades mínimas, médias e máximas de vento registradas no primeiro e segundo períodos das aplicações foram de 7, 14 e 23 km h-1 e 1, 5 e 18 km h-1, respectivamente. Nas duas ocasiões de aplicação, as pontas de pulverização com indução de ar AVI 11002 e de jato cônico vazio JA-2 a 655 kPa resultaram nas menores e maiores quantidades de depósito de líquido detectadas, respectivamente. A maior intensidade do vento incrementou a deriva. A redução na pressão pode ser utilizada para controle de deriva, mas a seleção adequada de uma ponta mostrou ser mais eficiente para esse propósito.

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Estudou-se o efeito do volume de substrato e da idade das mudas na produção de pepino japonês 'Hokuho' sob ambiente protegido na área experimental da UNESP, de março a julho/2000. Os tratamentos consistiram em dois volumes de substrato (34,6 e 121,2 cm³ em bandeja de poliestireno expandido) e quatro idades das mudas (19; 24; 29 e 34 dias após a semeadura). O delineamento experimental foi em blocos ao acaso, com cinco repetições e cinco plantas por parcela. Foram avaliados no dia do transplante o número de folhas, área foliar, comprimento, massa fresca e seca da parte aérea das mudas e, após o transplante, a produção precoce (porcentagem da produção nos primeiros 20 dias de colheita), produção de frutos (número e massa) e produção comercial (número e massa). Nas condições deste experimento, obteve-se maior precocidade com mudas de pepino produzidas em maior volume de substrato. Porém, a produção de frutos não apresentou diferença estatística quando utilizou-se mudas de pepino com menos de duas folhas produzidas em menor volume de substrato. A produção comercial foi superior com mudas produzidas em bandejas com maior volume de substrato. A idade não influenciou a produção comercial de frutos em mudas produzidas em volume de substrato maior, porém, quanto mais velhas as mudas produzidas em recipientes com menor volume de substrato, menor a produção destas plantas.

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A podridão de raízes, causada por Pythium aphanidermatum e outras espécies de Pythium, é a principal doença da alface cultivada em sistemas hidropônicos no Brasil. O presente trabalho teve como objetivo avaliar quatro cultivares comerciais de alface em relação à sensibilidade a podridão de raízes, causada por P. aphanidermatum. Os estudos foram realizados em placas de Petri contendo ágar-água com plântulas de alface das cultivares crespa (Vera e Verônica) e lisa (Regina e Elisa), infestadas ou não com o patógeno. Com as mesmas cultivares foram realizados quatro experimentos em sistemas hidropônicos (Nutrient Film Technique), sendo dois em estufa coberta com plástico e sombrite e dois em estufa coberta apenas com plástico. As plântulas, infectadas ou não com P. aphanidermatum, foram transplantadas para os sistemas infestados ou não. Foi avaliada a severidade da doença e o desenvolvimento das plantas. Todas as cultivares foram suscetíveis à podridão de raízes nos experimentos realizados in vitro e in vivo. A presença do sombrite não reduziu a podridão de raízes em cultivares de alface produzidas no sistema hidropônico. A cultivar Regina apresentou maior massa de matéria seca da parte aérea e das raízes, na presença ou ausência do patógeno, sendo a mais indicada para o cultivo hidropônico na época mais quente do ano.

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The oil industry, experiencing a great economic and environmental impact, has increasingly invested in researches aiming a more satisfactory treatment of its largest effluent, i.e., produced water. These are mostly discarded at sea, without reuse and after a basic treatment. Such effluent contains a range of organic compounds with high toxicity and are difficult to remove, such as polycyclic aromatic hydrocarbons, salts, heavy metals, etc.. The main objective of this work was to study the solar distillation of produced water pre-treated to remove salts and other contaminants trough of a hybrid system with a pre-heater. This developed apparatus was called solar system, which consists of a solar heater and a conventional distillation solar still. The first device consisted of a water tank, a solar flat plate collector and a thermal reservoir. The solar distillator is of simple effect, with 1m2 of flat area and 20° of inclination. This dissertation was divided in five steps: measurements in the solar system, i.e. temperatures and distillate flow rate and weather data; modeling and simulation of the system; study of vapor-liquid equilibrium of the synthetic wastewater by the aqueous solution of p-xylene; physical and chemical analyses of samples of the feed, distillate and residue, as well as climatology pertinent variables of Natal-RN. The solar system was tested separately, with the supply water, aqueous NaCl and synthetic oil produced water. Temperature measurements were taken every minute of the thermal reservoir, water tank and distillator (liquid and vapor phases). Data of solar radiation and rainfall were obtained from INPE (National Institute for Space Research). The solar pre-heater demonstrated to be effective for the liquid systems tested. The reservoir fluid had an average temperature of 58°C, which enabled the feed to be pre-heated in the distillator. The temperature profile in the solar distillator showed a similar behavior to daily solar radiation, with temperatures near 70°C. The distillation had an average yield of 2.4 L /day, i.e., an efficiency of 27.2%. Mathematical modeling aided the identification of the most important variables and parameters in the solar system. The study of the vapor-liquid equilibrium from Total Organic Carbon (TOC) analysis indicated heteroazeotropia and the vapor phase resulted more concentrated in p-xylene. The physical-chemical analysis of pH, conductivity, Total Dissolved Solids (TDS), chlorides, cations (including heavy metals) and anions, the effluent distillate showed satisfactory results, which presents a potential for reuse. The climatological study indicates the region of Natal-RN as favorable to the operation of solar systems, but the use of auxiliary heating during periods of higher rainfall and cloud cover is also recommended

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The aim of this work is to use a new technology in the treatment of produced wastewaters from oil industry. An unit for treat produced waters called UTMDIF, was designed, installed and operated in an industrial plant for treatment of effluents from oil industry. This unit operates by means of the method of separation of phase inversion and can become a promising alternative to solve the problem of oil/water separation. This method constitutes the basis of the working of a new design of mixersettler of vertical configuration which occupies small surface area. The last characteristic becomes specially important when there is limitation on the lay-out of the plant, for example, over maritime platforms to explore oil. This equipment in a semi-industrial scale treats produced wastewaters contaminated with oil at low concentrations (ranging from 30 to 150 mg/L) and throughputs of 320 m3/d (47,4 m3 m-2 h-1). Good results were obtained in oil/water separation which leads to the necessary specification to discharge those wastewaters. Besides, the non dependence of the efficiency of separation in spite of the salinity of the medium becomes the equipment an attractive new technology to treat wastewaters containing oil at low concentrations

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This work study of solar distillation feasibility in effluent of petroleum industry: produced water, making possible your reuse for irrigation of oleaginous cultures or fodder crops or in steam generation, as well the transport phenomena involved. The methodology for development of this project was to characterize the effluent to be treated and to accomplish physical and chemical analysis in the distilled, to build distillation equipment, concomitant operation of both equipments and implementation of data processing and economical evaluation. The methodology used for all parameters is outlined in APHA (1998) and sampling of the type compound. The feeding of distillation equipment was performed with treated effluent from UTPF of Guamaré. The temperature was monitored throughout the distillers and during the time of operation. The distillers feed occur, as a rule, for sifon. The distillers were operated by a period of 17 months between July 2007 and February 2009, in which 40 experiments were performed. The radiation and temperature datas were acquired in the INPE s site and the temperature inside of the distillers was registered by DATALOGGER Novus. The rates of condensation (mL / min) were determined by measuring of the flow in a graduate test tube of 10 mL and a chronometer. We used two simple solar effect distillers of passive type with different angles in coverage: 20 ° and 45 °. The results obtained in this study and the relevant discussions are divided into six topics: sample characterization and quality of distilled; construction of distillers; operation (data, temperature profile), climatic aspects, treatment of data and economical analysis. Results obtained can be inferred that: the energy loss by the adoption of vessel glass was not significant, however, complicates the logistics of maintenance the equipment on a large scale. In the other hand, the surface of the tub with a glass shield on the equipment deterioration, both devices showed similar performance, so there is not justified for use of equipment 450. With regard to the climatological study it was verified that the Natal city presents monthly medium radiation varying in a range between 350 and 600 W/m2, and medium of wind speed of 5 m / s. The medium humidity is around 70% and rainfall is very small. The regime of the system is transient and although it has been treated as a stationary system shows that the model accurately represents the distillers system's 20 degrees. The quality of the distilled with regard to the parameters evaluated in this study is consistent with the Class 3 waters of CONAMA (Resolution 357). Therefore we can conclude that solar distillation has viability for treat oilfield produced water when considered the technical and environmental aspects, although it is not economically viable

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Increasing concern with the environment, in addition to strict laws, has induced the industries to find altenatives to the treatment of their wastes. Actually, the oil industry has sought solutions to overcome a big environmental problem, i.e., oil field produced water being discharged to the sea. These effluents have organic compounds dissolved, such as polycyclic aromatic hydrocarbons, phenols, benzene, toluene, ethylbenzene and xylenes (BTEX). These compounds are difficult to be removed and have high toxicity. The advanced oxidation processes - AOP are effective to degradation of these organic compounds, because they generate hydroxyl radicals with high potential of oxidation. This work includes the reactor photochemical development applied in the photodegradation treatment (by photo-Fenton process) of wastewaters containing organic compounds dissolved, aiming at treatment and recovery the oil field produced water. The studied reactor allowed the evaluation of two ultraviolet radiation sources that is the main factor to describe the feasibility of the photo¬Fenton treatment, i.e., sun and black light fluorescent lamps, and other relevant variables the process: concentration of reagents, irradiated area and also various reactor configurations to maximize the use of radiation. The organic matter degradation was verified with samples collected during the experimental and analyzed with a total organic carbon analyzer (TOC), which expressed the results in terms of mgC/L. The solar radiation was more effective than radiation from the lamps. it's an important factor for the operation costs cutting. Preliminary experiments applied to oil field produced water treatment have showed satisfactory results, reducing up to 76 % of organic matter

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Increasing concern with the environment, in addition to strict laws, has induced the industries to find alternatives to the treatment of their wastes. Actually, the oil industry has sought solutions to overcome a big environmental problem, i.e., oil field produced water being discharged to the sea. These effluents have organic compounds dissolved, such as polycyclic aromatic hydrocarbons, phenols, benzene, toluene, ethylbenzene and xylenes (BTEX). These compounds are difficult to be removed and have high toxicity. The advanced oxidation processes - AOP are effective to degradation of these organic compounds, because they generate hydroxyl radicals with high potential of oxidation. This work includes the reactor photochemical development applied in the photodegradation treatment (by photo-Fenton process) of wastewaters containing organic compounds dissolved, aiming at treatment and recovery the oil field produced water. The studied reactor allowed the evaluation of two ultraviolet radiation sources that is the main factor to describe the feasibility of the photo- Fenton treatment, i.e., sun and black light fluorescent lamps, and other relevant variables the process: concentration of reagents, irradiated area and also various reactor configurations to maximize the use of radiation. The organic matter degradation was verified with samples collected during the experimental and analyzed with a total organic carbon analyzer (TOC), which expressed the results in terms of mgC/L. The solar radiation was more effective than radiation from the lamps. It's an important factor for the operation costs cutting. Preliminary experiments applied to oil field produced water treatment have showed satisfactory results, reducing up to 76 % of organic matter

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The work aimed to study the formation of Tabebuia chrysotricha Standl. seedlings in function of four substrates, varying the covering fertilization solutions. To compose the substrate it was used fibrous and granulated coconut fiber obtaining the following treatments: 100% fibrous (100% F), 60% fibrous + 40% granulated (60% F+40% G), 40% fibrous + 60% granulated (40% F+60% G) and 100% granulated (100% G). The basis fertilization was the same for all treatments and the solutions of covering fertilization varied in order to obtain complete solutions with electric conductivities of 1.06 dS m(-1), 2.12 dS m(-1), 3.2 dS m(-1) and 4.25 dS m(-1). The propagative material was sowed directly in plastic containers (120mL) with the respective substrates. The fertilization was received through sub-irrigation once a week, respecting the treatments of fertilizations. Seedlings produced in 100%G had been taller and higher than the others. The chemical analyses of aerial part were obtained when the seedlings were ready for expedition (height of 20 cm). The seedlings production in substrate 100% F and 60% F+40% G allowed them to have higher N, S, B, Mn and Zn concentrations in the aerial part. The production of T chrysotricha seedlings is recommended in granulated coconut fiber substrate and fertilizer solutions with EC of 1.06 dS m(-1)

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The green bean has organoleptic and nutritional characteristics that make it an important food source in tropical regions such as the Northeast of Brazil. It is a cheap source of protein and important for nutrition of rural population contributing significantly in subsistence farming of the families from Brazil s northeast. It is consumed in entire region and together with the dry meat and other products composes the menu of typical restaurants, being characterized as an important product for economy of Northeast. The green bean is consumed freshly harvested and has short cycle, being characterized as a very perishable food, which hampers your market. The drying method is an alternative to increase the lifetime and provide a reduction volume of this product making easier your transportation and storage. However is necessary to search ways of drying which keep the product quality not only from the nutritional standpoint but also organoleptic. Some characteristics may change with the drying process such as the coloring, the rehydration capacity and the grains cooking time. The decrease of drying time or of exposure of the grains to high temperature minimizes the effects related with the product quality loss. Among the techniques used to reduce the drying time and improve some characteristics of the product, stands out the osmotic dehydration, widely used in combined processes such as the pretreatment in drying food. Currently the use of the microwaves has been considered an alternative for drying food. The microwave energy generates heat inside of materials processed and the heating is practically instantaneous, resulting in shorter processing times and product quality higher to that obtained by conventional methods. Considering the importance of the green beans for the Northeast region, the wastefulness of production due to seasonality of the crop and your high perishability, the proposal of this thesis is the study of drying grain by microwaves with and without osmotic pretreatment, focusing on the search of conditions of processes which favor the rehydration of the product preserving your organoleptic characteristics. Based on the analysis of the results of osmotic dehydration and dielectric properties was defined the operating condition to be used in pretreatment of the green bean, with osmotic concentration in saline solution containing 12,5% of sodium chloride, at 40°C for 20 minutes. The drying of green bean by microwave was performed with and without osmotic pretreatment on the optimized condition. The osmotic predehydration favored the additional drying, reducing the process time. The rehydration of dehydrated green bean with and without osmotic pretreatment was accomplished in different temperature conditions and immersion time according to a factorial design 22, with 3 repetitions at the central point. According to results the better condition was obtained with the osmotically pretreated bean and rehydrated at a temperature of 60°C for 90 minutes. Sensory analysis was performed comparing the sample of the green bean in natura and rehydrated in optimized conditions, with and without osmotic pretreatment. All samples showed a good acceptance rate regarding the analyzed attributes (appearance, texture, color, odor and taste), with all values above 70%. Is possible conclude that the drying of green bean by microwave with osmotic pretreatment is feasible both in respect to technical aspects and rehydration rates and sensory quality of the product

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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It is possible to notice that the modern narrative increasingly seeks to invest its characters with a broad and complex nature, away from the well-defined beings of the traditional narrative. Through this work, we aim to make a study of Marcela, a character of the novel A ostra e o vento, by Moacir Costa Lopes, taking into account the way the complexity of the fictitious being is constituted through an analysis of structural, semantic, and thematic elements. We first will bring up a brief theoretical discussion about the character in a novel, and we also will carefully analyze the diagetic universe, presenting the complex path of the character further. Subsequently, we will focus on the structure of the narrative which creates a complex picture of the character, using the technique of crossed points of view as well as the technique of temporal fragmentation. Finally, we will investigate conflicting social relations that portray Marcela s disturbed inner side, as well as the metaphoric symbolic language, which furnishes a number of different representation of this character, impeding the creation of a well-structured coherent character. Studies of scholars such as Antonio Candido, Anatol Rosenfeld, Vitor Manuel de Aguiar e Silva, Fernando Segolin, Gerard Genette, Michel Zéraffa, among others, will guide our analysis

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A agregação plaquetária avalia a função das plaquetas através de diferentes vias de ativação plaquetária in vitro, fornecendo traçados de ondas equivalentes à propriedade física dessa agregação. Sabendo-se que a aspirina acetila irrever­sivelmente a enzima cicloxigenase prevenindo a geração de tromboxana A2, potente ativador da agregação plaquetária, esta droga tem sido analisada há mais de trinta anos na clínica médica em pacientes com doenças cardiovasculares como uma potente droga antitrombótica. Foram nossos objetivos obter traçados de ondas correspondentes às fases da agregação plaquetária para nossa padronização utilizando nosso grupo controle de doadores de sangue e compará-las com nosso grupo estudo, frente a diferentes agentes agonistas em diferentes concentrações: ADP 1µM e 3µM; AA, 0,5mM; ADR, 0,05 mg/mL, 0,025 mg/mL e 0,010 mg/mL. Os grupos analisados foram constituídos por 41 cardíacos e 40 doadores de sangue considerados controle. Dos cardíacos, 33 faziam uso regular do AAS na concentração de 200 mg/dia e oito na concentração de 100 mg/dia, sendo todos considerados hipertensos. A padronização da agregometria estava na dependência do encontro de traçados correspondentes a ondas de agregação, sendo esses obtidos em porcentagem no tempo de cinco minutos estandartizados pelo aparelho utilizado. Comparando os resultados entre os pacientes e o grupo controle, foi possível observar que, na presença dos agentes agregantes ADP 1µM e ADP 3 µM, ADR 0,05 mg/mL, 0,025mg/mL e 0,010 mg/mL, os pacientes apresentaram 1ª onda, mas não 2ª onda. Por sua vez, no caso do AA 0,5 mM não houve o encontro de traçados de ondas.