999 resultados para Influência


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Petroleum Refinery wastewaters (PRW) have hart-to-degrade compounds, such as: phenols, ammonia, cyanides, sulfides, oils and greases and the mono and polynuclear aromatic hydrocarbons: benzene, toluene and xylene (BTX), acenaphthene, nitrobenzene and naphtalene. It is known that the microrganisms activity can be reduced in the presence of certain substances, adversely affecting the biological process of wastewater treatment. This research was instigated due the small number of studies regarding to this specific topic in the avaiable literature. This body of work ims to evaluate the effect of toxic substances on the biodegradability of the organic material found in PRW. Glucose was chosen as the model substrate due to its biodegradable nature. This study was divided into three parts: i) a survey of recalcitants compounds and the removal of phenol by using both biological and photochemical-biological processes; ii) biomass aclimation and iii) evaluation of the inhibitory effect certain compounds have on glucose biodegradation. The phenol degradation experiments were carried out in an activity sludge system and in a photochemical reactor. The results showed the photochemical-biological process to be more effective on phenol degradation, suggesting the superioruty of a combined photochemical-biological treatment when compared with a simple biological process for phenol removal from industry wastewaters. For the acclimation step, was used an activated sludge from industrial wastewaters. A rapid biomass aclimation to a synthetic solution composed of the main inhibitory compouns fpund in a PRW was obtained using the following operation condition: (pH = 7,0; DO ≥ 2,0 mg/L; RS = 20 days e qH = 31,2 and 20,4 hours), The last part was consisted of using respirometry evaluation toxicity effects of selected compounds over oxygen uptake rate to adaptated and non adaptated biomass in the presence of inhibitory compounds. The adaptated sludge showed greater degration capacity, with lower sensibility to toxic effects. The respirometry has proved to be very practical, as the techiniques used were simple and rapid, such as: Chemical Oxygen Demand (COD), Dissolved Oxygen (DO), and Volatile Suspended Solids (VSS). Using the latter it is possible to perform sludge selection to beggingthe process; thus allowing its use for aerobic treatment system`s behacior prediction

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This work aims at studying the influence of the concentration of calcite, its grain size and sintering temperature to obtain porous coating formulations that meet the design specifications. The experiments involved the physical-chemical and mineralogical caracterization of the raw materials, and mechanical tests on specimens dried and sintered, performing a planning mixture and factorial experiment, using the response surface methodology. The ceramic bodies studied were prepared by dry process, characterized, placed in conformity by uniaxial pressing and sintered at temperatures of 940 º C, 1000ºC, 1060ºC, 1120°C and 1180°C using a fast-firing cycle. The crystalline phases formed during sintering at temperatures under study, revealed the presence of anorthite and wolastonite, and quartz-phase remaining. These phases were mainly responsible for the physical and mechanical properties of the sintered especimens. The results shown that as increases the participation of carbonate in the composition of ceramic bodies there is an increase of water absorption and a slight reduction in linear shrinkage for all sintering temperatures. As for the mechanical strength it was observed that it tended to decrease for sintering at temperatures between 940 ° C and 1060 ° C and to increase for sintering at temperatures above 1060 ° C occurring with greater intensity for compositions with higher content of calcite. The resistence decreased with increasing participation of quartz in all sintering temperatures. The decrease in grain size of calcite caused a slight increase in water absorption for formulation with the same concentration of carbonate, remaining virtually unchanged the results of linear shrinkage and mechanical strength. In conclusion, porous ceramic coating (BIII) can be obtained using high concentrations of calcite and keeping the properties required in technical standards and that the particle size of calcite can be used as tuning parameter for the properties of ceramic products.

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Escherichia coli has been one of the most widely used hosts in recombinant protein production, in both laboratory and industrial scale since the advent of recombinant DNA technology. Despite the substantial progress of studies on the molecular biology and immunology of infections, there is currently no medication-based prophylaxis capable of preventing leishmaniasis. As such, there is a great need to identify specific antigens for the development of vaccines and diagnostic kits against visceral leishmaniasis. Thus, the primary goal of the present study is to assess the influence of cultivation conditions on the production of Leishmania chagasi antigens, carried out in a rotating incubator and bioreactor. To that end, several assays were conducted to evaluate the kinetic behavior of antigens (648, 503) of Leishmania. i. chagasi in two different compositions of media (2xTY, TB), with and without an inducer. In order to improve expression, assays were performed in a benchtop bioreactor using the best conditions obtained in a rotating incubator, in addition to assessing the influence of stirring speed. Results show that high complexity of the cultivation medium favored kinetic growth of clones (648, 503). However, in assays submitted to induction by IPTG, this elevated complexity did not promote the expression of recombinant proteins. Expression of antigens 648 and 503 exhibited behavior associated with growth and, in terms of location, proteins 648 and 503 are intracellularly stored. Lactose may be the most adequate inducer in protein expression, when considering factors, cost, toxicity and stability. Elevated stirring may increase cell growth in clone 53, although it may not result in high concentrations for the protein of interest. On the other hand, positive results were obtained for all recombinant clones (648, 503) tested, confirmed by the electrophoretic profile

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Gallium is an important material used in the electronic industry whose demand in the world market is increasing in view of its potential applications. A selective technique is required to allow for the production of the metal, separated from aluminium. Due to the fact that microemulsions constitute an attractive alternative to metal extraction procedures, microemulsified systems have been employed as gallium-selective extraction agents. Two surfactants have been synthesized: sodium 12-N,N-diethylamino-9,10-dihydroxyestearate (AMINE) and saponified coconut oil (SCO), both produced from raw materials readily available in Northeastern Brazil. Also, the commercial extraction agent KELEX-100, conventionally used with the same purpose, has been used in this work for comparison. The optimization of the extraction process with microemulsions was carried out by investigating the influence of some parameters, namely the type of cosurfactant, the cosurfactant/surfactant (C/S) ratio, the pH and concentration of metals in the aqueous phase. Pseudoternary diagrams, which are representative of the microemulsified systems under study, have been constructed in order to establish the boundaries of the regions where the several Winsor systems are formed. An experimental planning methodology (Scheffé Net) has been used to optimize the extraction. The extraction percentage values were as high as 100% for gallium and 99.99% for aluminium for the system with KELEX-100; 96.6% for gallium and 98.8% for aluminium for the system containing AMINE; and 88% for gallium and 85% for aluminium for the system with SCO. The microemulsified system chosen for presenting the best results in gallium extraction was composed by SCO/isoamyl alcohol/kerosene/Bayer licquor with a C/S ratio of 28 and pH of the original aqueous phase of 6.0. The selectivity that has not been observed in the extraction stage was accomplished in the reextraction process using HCl. For the KELEX-100 system, gallium was reextracted at 100% with 6M HCl and aluminium was reextracted at 100% with 0.8M HCl. For the AMINE system, the reextraction percentages were also 100% for both metals, using 6M HCl for gallium and 0.5M HCl for aluminium. On the other hand, the reextraction percentages for the system with SCO were as high as 84% for gallium and 92% for aluminium, with HCl in the same concentrations as those used in the AMINE system. Finally, an optimized system was applied in the gallium extraction process employing a reciprocating perforated-plates extractor. As a result, the metal content was extracted at a recovery rate of 95% for gallium and 97% for aluminium

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O tomate é um fruto muito perecível por causa do seu conteúdo de umidade. A secagem é uma das práticas industriais mais utilizadas em alimentos para manter a qualidade do produto final. A pesquisa foi desenvolvida para estudo dos parâmetros de secagem de tomate (Lycopersicon esculentum Mill), cv Carmen, com relação ao tipo de corte (meio e um quarto) e à temperatura de processo (60 e 70 ºC), bem como à escolha do tempo de secagem para a obtenção de um produto com umidade de 45% (base úmida). As cinéticas de secagem foram determinadas experimentalmente por convecção forçada e ajustadas ao modelo de Page. Os resultados obtidos mostraram que a geometria de corte influenciou na taxa de secagem e no tempo de desidratação. Os tomates cortados em quatro partes e desidratados a 70 ºC alcançaram umidade de 45% em menor tempo (10 horas), quando comparados aos tomates com o corte em metades. O modelo de Page forneceu bom ajuste nas cinéticas de secagem

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The Pirangi beach is located in the eastern coastline of Rio Grande do Norte state, in the municipality of Parnamirim and Nísia Floresta. In it flow into Pirangi Watershed (PW), whose water receives large amounts of pollutants, mainly domestic and industrial sewage from districts where pass the rivers that consist it, compromising, thus, the bathing water quality of the Pirangi beach. Bearing in mind the importance of water sanitary quality to ensure an environment that no present risk to the bathers s health, this work had as main objective to assess the influence of the PW s waters in the bathing water quality of the Pirangi beaches. To that end, were made collections of water in the beaches and in the rivers with the intention of quantify the fecal contamination indicators thermotolerant coliforms and enterococci, to then classify the conditions of bathing water quality according with the CONAMA Resolution number 274 of 2000. For the purposes greater knowledge about the health conditions of the Beaches Pirangi and about the influence the PW s waters exert on it, was done parallely to the study of the water quality, an investigation of the sand sanitary quality. Furthermore, it was made an evaluation of the PW s Water Quality through Water Quality Index (WQI). Starting from the results obtained in the research present was possible to verify, among other aspects, that the entry of the PW s waters in the Pirangi beaches exerts direct influence in the bathing water quality of the same ones, being the North Pirangi beach (point tracking PA-02) the most influenced. There was noticed also a significant reduction in the conditions of bathing water quality of the beaches in the rainy season. However, the precariousness do sewerage system of the Natal metropolitan region and the absence of a right system of treatment an final disposal of domestic sewage and industrial are the main factors responsi le for deterioration of the PW s Water Quality, and as a consequence, compromising the bathing water quality of the Pirangi beaches

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Digital Elevation Models (DEM) are numerical representations of a portion of the earth surface. Among several factors which affect the quality of a DEM, it should be emphasized the attention on the input data and the choice of the interpolating algorithm. On the other hand, several numerical models are used nowadays to characterize nearshore hydrodynamics and morphological changes in coastal areas, whose validation is based on field data collection. Independent on the complexity of the physical processes which are modeled, little attention has been given to the intrinsic bathymetric interpolation built within the numerical models of the specific application. Therefore, this study aims to investigate and to quantify the influence of the bathymetry, as obtained by a DEM, on the hydrodynamic circulation model at a coastal stretch, off the coast of the State of Rio Grande do Norte, Northeast Brazil. This coastal region is characterized by strong hydrodynamic and littoral processes, resulting in a very dynamic morphology with shallow coastal bathymetry. Important economic activities, such as oil exploitation and production, fisheries, salt ponds, shrimp farms and tourism, also bring impacts upon the local ecosystems and influence themselves the local hydrodynamics. This fact makes the region one of the most important for the development of the State, but also enhances the possibility of serious environmental accidents. As a hydrodynamic model, SisBaHiA® - Environmental Hydrodynamics System ( Sistema Básico de Hidrodinâmica Ambiental ) was chosen, for it has been successfully employed at several locations along the Brazilian coast. This model was developed at the Coastal and Oceanographical Engineering Group of the Ocean Engineering Program at the Federal University of Rio de Janeiro. Several interpolating methods were tested for the construction of the DEM, namely Natural Neighbor, Kriging, Triangulation with Linear Interpolation, Inverse Distance to a Power, Nearest Neighbor, and Minimum Curvature, all implemented within the software Surfer®. The bathymetry which was used as reference for the DEM was obtained from nautical charts provided by the Brazilian Hydrographic Service of the Brazilian Navy and from a field survey conducted in 2005. Changes in flow velocity and free surface elevation were evaluated under three aspects: a spatial vision along three profiles perpendicular to the coast and one profile longitudinal to the coast as shown; a temporal vision from three central nodes of the grid during 30 days; a hodograph analysis of components of speed in U and V, by different tidal cycles. Small, but negligible, variations in sea surface elevation were identified. However, the differences in flow and direction of velocities were significant, depending on the DEM

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In semiarid region of northeast Brazil, the majority of reservoirs used for public supply has suffered degradation of water quality affected by diffuse pollution from agricultural and livestock areas of the watershed and by hydrologic regime peculiar to the region, characterized by a rainy season with higher volumes stored in reservoirs and a dry season with a reduction in water level due to high evaporation and increase of eutrophication. The Dourado reservoir, located in Currais Novos city, semiarid region of Rio Grande do Norte state, is one example of a water supply reservoir that can have degradation of water quality and impracticability of their use, due to the high external input of nutrients from non-point sources of watershed during the rainy season and increasing of eutrophication due to decrease the stored volume during the dry period. This study aimed to investigate and quantify diffuse pollution and the hydrologic regime of semiarid region in order to establish standards regarding the water quality of Dourado reservoir. The study period was between the months of May 2011 to March 2012. The diffuse pollution was quantified in terms of watershed from the mass balance of phosphorus in the reservoir, as in relation to areas under different types of land use within the riparian zone of the reservoir from the assessment of soil chemical properties and losses of phosphorus in each area. The influence of hydrological regime on water quality of the reservoir was evaluated from the monthly monitoring of the morphometric, meteorological and limnological features throughout the study period. The results showed that the reservoir has received a high load of phosphorus coming from the drainage basin and presents itself as a system able to retain some of that load tributary, giving an upward trend of the eutrophication process. Diffuse pollution by nutrients from areas under different types of land use within the riparian zone of the reservoir was higher in areas under the influence of livestock, being this area considered a potential diffuse source of nutrients to the reservoir. Regarding the water regime during the rainy season the reservoir was characterized by high concentrations of nutrients and small algal biomass, while in the dry season the reduction of volume and increase of the water retention time of the reservoir, contributing to the excessive growth algal biomass, favoring an increase in eutrophication and deterioration of water quality. In synthesis the water quality of Dourado reservoir is directed by diffuse pollution coming from the drainage basin and the hydrological regime of the peculiar semiarid region, where the rainy season is characterized by high input of allochthonous compounds from the tributaries and erosion of the soil in the reservoir riparian zone, and the dry season characterized by reducing the storage volume due to high evaporation, high residence time of water and consequent degradation of water quality due to the increase of eutrophication process

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The building of water reservoirs has become a solution for water scarcity of the semiarid regions, however, the land use and occupation near the margins of the reservoirs have been causing serious damage to water quality, harming their use. This paper aims to analyze the land use and occupation in the margins of the Northeast reservoir and evaluate their influence on the water quality, to identify the areas and activities that represent an higher risk of contamination to the reservoir. The study was conducted at the reservoir Dourado, located in the city of Currais Novos - RN, during the period from August 2012 to February 2013. Were defined six areas regarding the land use and occupation, then, Water samples were collected from the margins in these areas for the characterization of water quality. The results showed that almost all Permanent Preservation Areas (PPA) from the reservoir is degraded, increasing the susceptibility of large input of nutrients and contaminants loads. The water reservoir showed low quality, being with strong evidence of eutrophication due to the nutrient accumulation arising from the activities surrounding the reservoir, mainly from agriculture and Livestock. The Areas 1 and 2 are the areas that present a greater risk of reservoir degradation, because are the possible major sources of nutrients (phosphorus total, orthophosphate and nitrate), however, due to the small size of the reservoir, any compound that reaches its margins ultimately affects the water quality of the same

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In the semiarid region of northeastern of Brazil, the reservoirs are vulnerable to water level seasonal fluctuations, they re related to the hydrological cycle. The rain periods are irregular and there are long periods of drought that increases eutrophication process. That happens because of the water level s reduction and nutrient concentration. The Boqueirao, located in northeastern Brazil , is a mesotrophic reservoir. The reservoir is naturally susceptible to deterioration of water quality. This happens because of the potential diffuse sources arising from the use and occupation of the basin, associated with shallow soil caatinga biome and highly vulnerable to erosion. This study aimed to analyze the influence of the use and occupation of the area around and the water quality of the watershed. A study of the area around the Boqueirão was performed, taking the potentially polluting activities. Limnological variables were monitored monthly in 3 points of the reservoir to assess the water quality. Was evidenced an event of prolonged drought, with rainfall below the historical average for the year of study. By the index of water quality, the watershed was classified as " good " during the whole year of 2012. According to the trophic index adopted the reservoir is characterized as mesotrophic. The main anthropogenic impacts identified in the soil were arboreal selective logging, mining, diffuse contribution of residues from agricultural and livestock activities. The lack of precipitation and the degradation of the surrounding area, affect negatively the water quality, requiring immediate control to prevent degradation of the watershed . Although there wasn t a majority polluting activity in the region. The total of several impacting activities, the high susceptibility of the soil and the selective clearing of caatinga vegetation can accelerate the natural process of eutrophication in the water body

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Image acquisition systems based on multi-head arrangement of digital frame cameras, such as the commercial systems DMC, UltraCam, besides others, are attractive alternatives enabling larger imaging area when compared to a single frame camera. Considering that in these systems, cameras are tightly attached to an external mount, it is assumed that relative position and orientation between cameras are stable during image acquisition and, consequently, these constraint can be included in the calibration step. This constraint is acceptable because estimates of the relative orientation (RO) parameters between cameras, from previously estimated exterior orientation parameters, present higher and significant deviations than the expected physical variations, due to error propagation. In order to solve this problem, this work presents an approach based on simultaneous calibration of two or more cameras using constraints that state that the relative rotation matrix and the distance between the cameras head are stable. Experiments with images acquired by an arrangement of two Hasselblad H2D cameras were accomplished, without and with the mentioned constraints. The experiments showed that the calibration process with RO constraints allows better results than the approach based on single camera calibration, provided that the estimation has included only images with good target distribution.

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To analyze influences of the physical activity and sedentary behaviors on indicators of both central and total body fat in male adolescents. Cross-sectional study with 60 male students of age range from 11 to 14 years old. It were evaluated the body mass, height, triceps skinfold, waist circumference, body fat percentage (bioelectrical impedance) and the physical activity level through questionnaire. The physical inactivity prevalence was of 35%, and the excessive total and central body fat were observed in 38.3% and 48.3% of the sample, respectively. There was association of the sedentary behaviors with the excessive total and central body fat (OR = 5.2 e OR = 6.4, respectively), however there was not for physical activity. The adoption of sedentary behaviors is associated at the development of the total and central obesity among male adolescents.

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

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Diese These besteht aus der Analyse der Enteignungsverhältnisse und der Misselung, welche in den Texten der Ursprung des Kunstwerkes und die Hymnen Hölderlins vorkommen. Germanien und der Rhein sind in den 30en-Jahren letzten Jahrhunderts von Martin Heidegger verfasst worden. Ab anwendung der kritischen Methodologia von Harold Bloom und der starken Texgestaltung von Richard Rorty wird es deutlich, dass die Heideggers Lesungen der Hölderlins Poesia als ei Ersatzversuch der von Hegel entwickelte Kulturgeschichte ab deutescher Überlieferung klassicher Studien, die das tragische Erlebnis der alten Griechen als grundlegender Punkt des Westen Daseins vorbringen, verstanden werden können. So verlegt Heidegger die Aufbauachse der Entstehungserzälung des Abendlandes in Richtung Dichtkunst, indem er in seiner Wendung zum Dichterischen gleichzeitig auf der Suche nach einer abweichenden Feststellung der vorherrschaftlichen These ist, in welcher die Tragödie das grosse Antrittsereignis der westlichen Zivilisation darstellt, und darüber hinaus noch der Herstellung einer innigen Verbindung zwischen der Poesie von Hölderlin und Hesiudus, um die Enge der dichterischen Überinstimmung zu zeigen, welche die alten Griechen und die zeitegemässigen Deutschen verbrände. Dieser geistige Aufbau Heideggers hat man somit als ein überholungsversuch Hegels Einfluss und Denkungsart zur Vollendung der von Nietzsche begonnenen Überwindungsaufgabe des Hegelianismus´zu verstehen

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)