958 resultados para Região Hidrográfica Tocantins-Araguaia
Resumo:
This study reviews the spatial configuration from the road network of an urban compound formed by the cities of Crato, Juazeiro do Norte and Barbalha (the Crajubar - core of the Cariri metropolitan region, in the State of Ceará, Brazil), in order to establish nexus (or relations) between different levels of accessibility and the formation/ transformation and specialization of centralities in local and metropolitan scales. Stemming from the Social Logic of Space theoretical and operational apparatus, the study explores modeling possibilities (with axial lines, segments and lines of continuity) which is then confronted to empirical observations concerning movement flows and land use, within a Geographic Information System database. At different scales of analysis, the results suggest evidences of continuity were found in the permanence of intra-urban centres and sub-centres within each town, whereas evidences of change pointed out to the formation of a new centrality of metropolitan magnitude in the neighbourhood referred to as the Triângulo, in the municipality of Juazeiro, where high levels of topological accessibility coincides with the appearance of new business buildings as well as with the emergence of urban equipment of a scale more adequate to meet a regional demand
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The eutrofization is a natural process of accumulation of nutrients in aquatic´s body that it has been accelerated for the human´s actives, mainly the related with the activities of camp, industrial and the inadequate disposition of the domestic sewage. The enrichment of the aquatic´s body with nutrients, mainly the nitrogen and the phosphorus, and the consequent proliferation of algae and Cyanobacteria can commit the quality of the water for the public provisioning, for the fish farming and for other ends. The problem becomes more critical when there is a shortage of water naturally as in the semi-arid area of the Brazilian northeast. Before that problem this work had as objective evaluates the trophic state of six reservoirs of the basin of River Seridó of Rio Grande of Norte and also estimate the capacity of load of match of the reservoir and risk probabilities based on the established limits by the resolution Conama 357/05. The results demonstrate that the six reservoirs are eutrofization, with concentration of total phosphorus and cloro a in the water upster to 50 e 12 μg l-1. The results show that space homogeneity exists in the state trophic of the reservoirs, but a significant variation interanual in function of the increase of the concentrations of nutrients and decrease of the transparency of the water with the reduction of the body of water accumulated in the reservoirs.The results of the simulation risk estocastic show that the reservoirs could receive annually from 72 to 216 Kg of P, assuming a risk of 10% of increasing in more than 30 μg l-1 the annual medium concentrations of total match in the water of these reservoirs. This load could be high in until 360 kg of P a year in case the managers assume a risk of 10% of increasing in more than 50 μg l-1 the annual medium concentrations of total phosphorus in the waters of these reservoirs
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In Brazilian semiarid region, the majority of water bodies are temporary and the biodiversity in these ecosystems is poorly known. The goal of this study was to describe the temporal variation of benthic macroinvertebrates in an intermittent stream in the Brazilian semiarid region. From March to July of 2009, surveys of benthic macroinvertebrates and water physiochemical parameters were done in a first order stream located at Piranhas-Açu River basin. 25 macroinvertebrates families were found, 21 belonging to Insecta class. The chironomids were the most abundant group during all study period and were represented by 19 genus. The largest densities and taxonomic richness were seen in the drying phase of the stream while the smallest values were found in the period with the heaviest rainfalls ( wet phase ). Only the families Chironomidae and Ceratopogonidae were found during all study period, suggesting that these groups have better adaptations to support floods and droughts. Furthermore, these two groups seemed to be pioneering in this stream. Among the chironomids, Paratendipes dominated the period of floods while Tanytarsus were more abundant in the drying phase . This study showed that hydrological fluctuation is the main force influencing the macroinvertebrate community in this stream, therefore, efforts seeking the conservation and management of Brazilian semiarid water bodies should consider this high natural variability in flow regime
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Leachates are effluent produced by decomposition of solid waste, they have complex composition and can be highly toxic. Therefore such percolated liquid should be collected and treated properly to avoid environmental contamination of soil and of water bodies. The objective of this study was to evaluate the toxicity through ecotoxicological tests with Ceriodaphnia dubia (Cladocera - Crustacea) of percolated liquids generated in two different systems of municipal solid waste (MSW) disposal in the city of Natal/ RN: A Sanitary Landfill in the Metropolitan Region of Natal/ RN, and in a dump off area. Furthermore, it was evaluated the possible contamination of the underground water of the dump off area. Two monthly samples were taken at four points between the months of May/2009 and January/2010. The Point "A" corresponds to the end of the pond leachate treatment in ASRMN; The Point "B" corresponds to a containment pond at the dump. The Point "C" is an area near one of the cells of the dump off area where the leachate outcrops; The Point "D" stands for an underground water well at the area. The last point, called "E" was sampled only once and corresponds to the slurry produced by temporary accumulation of solid waste in the open area of the dump. The ecotoxicological tests, acute and chronic, followed the ABNT 13373/2005 rules, with some modifications. The samples were characterized by measuring the pH number, the dissolved oxygen (DO), the salinity, BOD5, COD, Cd, Cu, Pb, Cr, Fe, Mg, Ni, and Zn. At Point A, the average number of EC50-48h ranged between 1.0% and 2.77% (v/v), showing a high toxicity of the leachate to C.dubia in all months. To this point, positive correlations were found between the EC50- 48 with precipitation. Negative correlations were found between the EC50- 48h with salinity. At point B there was no response of the acute exposure of organisms to the test samples. At point C the EC50-48h ranged from 17.68% to 35.36% in just two months of the five ones analyzed, not correlated meaning. Point D, the EC50-48h level ranged between 12.31% and 71.27%, showed a negative correlation with, only, precipitation. Although it was observed toxicity of underground water in the Landfill Area, there was no evidence of water contamination by leachate, however, due to the toxic character of this water, additional tests should be conducted to confirm the quality of water that is used for human supply. At point E there was no acute toxicity. These results support the dangers of inappropriate disposal of MSW to water bodies due to the high toxicity of the leachate produced highlighting the necessity of places of safe confinement and a treatment system more effective to it
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The response of zooplankton assemblages to variations in the water quality of four man-made lakes, caused by eutrophication and siltation, was investigated by means of canonical correspondence analysis. Monte Carlo simulations using the CCA eingenvalues as test statistics revealed that changes in zooplankton species composition along the environmental gradients of trophic state and abiogenic turbidity were highly significant. The species Brachionus calyciflorus, Thermocyclops sp. and Argyrodiaptomus sp. were good indicators of eutrophic conditions while the species Brachionus dolabratus, Keratella tropica and Hexarthra sp. were good indicators of high turbidity due to suspended sediments. The rotifer genus Brachionus was the most species-rich taxon, comprising five species which were associated with different environmental conditions. Therefore, we tested whether this genus alone could potentially be a better biological indicator of these environmental gradients than the entire zooplankton assemblages or any other random set of five species. The ordination results show that the five Brachionus species alone did not explain better the observed pattern of environmental variation than most random sets of five species. Therefore, this genus could not be selected as a target taxon for more intensive environmental monitoring as has been previously suggested by Attayde and Bozelli (1998). Overall, our results show that changes in the water quality of man-made lakes in a tropical semi-arid region have significant effects on the structure of zooplankton assemblages that can potentially affect the functioning of these ecosystems
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Tangara da Serra is located on southwestern Mato Grosso and is found to be on the route of pollutants dispersion originated in the Legal Amazon s deforestation area. This region has also a wide area of sugarcane culture, setting this site quite exposed to atmospheric pollutants. The objective of this work was to evaluate the genotoxicity of three different concentrations of organic particulate matter which was collected from August through December / 2008 in Tangara da Serra, using micronucleus test in Tradescantia pallida (Trad-MCN). The levels of particulate matter less than 10μm (MP10) and black carbon (BC) collected on the Teflon and polycarbonate filters were determined as well. Also, the alkanes and polycyclic aromatic hydrocarbons (PAHs) were identified and quantified on the samples from the burning period by gas chromatography detector with flame ionization detection (GC-FID). The results from the analyzing of alkanes indicate an antropic influence. Among the PAHs, the retene was the one found on the higher quantity and it is an indicator of biomass burning. The compounds indene(1,2,3-cd)pyrene and benzo(k)fluoranthene were identified on the samples and are considered to be potentially mutagenic and carcinogenic. By using Trad-MCN, it was observed a significant increase on the micronucleus frequency during the burning period, and this fact can be related to the mutagenic PAHs which were found on such extracts. When the period of less burnings is analyzed and compared to the negative control group, it was noted that there was no significant difference on the micronuclei rate. On the other hand, when the higher burning period is analyzed, statistically significant differences were evident. This study showed that the Trad-MCN was sensible and efficient on evaluating the genotoxicity potencial of organic matter from biomass burning, and also, emphasizes the importance of performing a chemical composition analysis in order to achieve a complete diagnosis on environmental risk control
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The aetiology of autoimmunes disease is multifactorial and involves interactions among environmental, hormonal and genetic factors. Many different genes may contribute to autoimmunes disease susceptibility. The major histocompatibility complex (MHC) genes have been extensively studied, however many non-polymorphic MHC genes have also been reported to contribute to autoimmune diseases susceptibility. The aim of the present study was to evaluate the influence of SLC11A1 gene in systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Ninety-six patients with SLE, 37 with RA and 202 controls enrolled in this case-control study, were evaluated with regard to demographic, genetic, laboratorial and clinical data. SLE mainly affects females in the ratio of 18 women for each man, 88,3% of the patients aged from 15 to 45 years old and it occurs with similar frequency in whites and mulattos. The rate of RA between women and men was 11:1, with 77,1% of the cases occurring from 31 to 60 years. The genetic analysis of the point mutation -236 of the SLC11A1 gene by SSCP did not show significant differences between alleles/genotypes in patients with SLE or RA when compared to controls. The most frequent clinical manifestations in patients with SLE were cutaneous (87%) and joint (84.9%). In patients with RA, the most frequent out-joint clinical manifestation were rheumatoid nodules (13,5%). Antinuclear antibodies were present in 100% of the patients with SLE. There was no significant relation between activity of disease and presence of rheumatoid factor in patients with RA, however 55,6% of patients with active disease presented positive rheumatoid factor. Significant association between alleles/genotypes of point mutation -236 and clinical manifestations was not found
Resumo:
Brazil is a great ceramic raw materials productor because of the its big number of clay deposits, in various areas of the ceramic industry. Although, the majority of the natural reservations are unknown or not studied yet, so there is no scientific technical dates that can guide their usage and industrial application, as well as the racional and optimazed way of usage by the industrial sector. The state of Maranhão has a gigant mineral wealth as esmectite, bentonite, kaolin, clays, feldspates, marine salt, iron and others, but produce only products with small agregated value compared to the porcelanato, one of the most expensives ceramic cover tiles, the reason for that is the low water absorption (lower than 0,5%), beside present amazing tecnicals features, like mechanical resistence. The main objective of the work is to do the characterization of four clays, with the finallity of find an application by the results and develop formulations to produce porcelanato using these raw materials from Timon-MA. For this were made the raw materials characterization using X ray fluorecence; X ray diffraction; Differencial thermal analysis; Dilatometric analysis and Tecnological properties, planing three formulations that were sinterized at six different temperatures: 1150, 1170, 1190, 1210, 1230 and 1250ºC for 7 minutes. After the sinteratization, the samples were submitted to tension resistance analysis. Were attained two formulations with the requested properties to produce porcelanato
Resumo:
This research presents an outlook of the industries of red ceramic in the region next to the city of Teresina and an analysis of the ceramic products producted in this pole. The microregion investigated possesses 13 boroughs where were identified 32 ceramic in operation, being that 24 are located in Teresina, the ceramic region more important of Piauí, 1 is located in the city of Miguel Leão and 7 is located in Timon city that belongs to the state of Maranhão. The majority of ceramics are pulverized in these two cities, Teresina and Timon , responsible by a largely production independent of distance between fabric and consumer market. Furthermore, there is an artisanal production realized in other boroughs, mainly manual conformation bricks, where are producted diverse types of handicraft and ceramics utilitarian. The objective of this research is to evalue the conformity of ceramic blocks for brick of obstruction made by red ceramic industry of microregion at studying, verifying their pontentialities and adequacy in terms of production. In this research universe made a search of ceramic industries related to the Foundation CEPRO (Foundation Center of Research Social and Economic of Piauí). For the analysis of the ceramic products , were colected 60 crude bricks sample in three industries for their characterization, and 39 burned bricks sample for the Evaluation of Conformity. The results of the characterization made reached a accetptable standard in all formulations and temperature studied. The burned samples were applied to the geometric, physical and mechanical assays according to the ABNT standards (Brazilian Association of Technical Standards). The results of the physical assays showed that all the samples are at the same band recommended by standard. However, through the geometric assays just two industries did not present results according to the standard, due to lack of control in their process such as in their equipments. Taking into account the mechanical properties, only one industry investigated was not according to the standard
Resumo:
The failure of materials is always an unwelcome event for several reasons: human lives are put in danger, economic losses, and interference in the availability of products and services. Although the causes of failures and behaviour of materials can be known, the prevention of such a condition is difficult to be guaranteed. Among the failures, wear abrasion by the low voltage is the kind of failure that occurs in more equipment and parts industry. The Plants Sucroalcooleiras suffer significant losses because of such attrition, this fact that motivated their choice for the development of this work. For both, were considered failures in the swing hammers desfibradores stopped soon after the exchange provided in accordance with tonnage of cane processed, then were analyzed by the level of wear testing of rubber wheel defined by the standard ASTM G65-91.The failures were classified as to the origin of the cause and mechanism, moreover, were prepared with samples of welding procedures according to ASME code, sec. IX as well, using the technique of thermal spraying to analyze the performance of these materials produced in laboratories, and compares them with the solder used in the plant. It was observed that the bodies-of-proof prepared by the procedure described as welding, and the thermal spraying the results of losing weight have been minimized significantly compared to the preparations in the plant. This is because the use of techniques more appropriate and more controlled conditions of the parameters of welding. As for the thermal spraying, this technique has presented a satisfactory result, but requires the use of these coatings in the best condition for real affirmation of the results
Resumo:
This work had to verify the influence of massará, while mortar component, in the process of formation of saltpeter in cementitious plaster walls of buildings. The massará is a ceramic material, texture areno usually found in large volumes argillaceous sediments in Teresina, Piaui State capital, which is associated with the Portland cement mortar form for fixing and finishing in construction. Saltpeter or flowering is a pathology that happens in gypsum wallboard, which invariably reaction between soluble salts present in materials, water and oxygen. This pathology, supposedly credited to massará caused its use to suffer significant reduction in the market of the buildings. Verify this situation with particular scientific rigor is part of the proposal of this work. Grading tests Were performed, consistency limits (LL, LP and IP), determination of potential hydrogen, capacity Exchange (CTC), electrical conductivity (EC), x-ray fluorescence (FRX) and x-ray diffraction (DRX). Massará analysed samples in number six, including sample plastering salitrado presented potential hydrogen medium 5.7 in water and 5.2 on KCl n and electrical conductivity (EC), equal to zero. These results pointed to the affirmative that massará is a material that does not provide salinity content that can be taken into consideration. It is therefore concluded that the material analyzed not competing, at least with respect to the presence of soluble salts, for the formation of saltpeter
Resumo:
In the State Rio Grande do Norte, Brazil, the most significant deposits of minerals in the production of granite and pegmatite are Seridó region. Municipalities of Parelhas and Equador are the main responsible for the production of feldspar, quartz, kaolin and granite. The ceramic industries are always in search of competitiveness by investing in new products or improving existing techniques. The stoneware is a type of pottery that stands in the market because it presents technical and aesthetic characteristics superior to other existing products. Characteristics of the raw materials initially obtained with chemical analysis and mineralogical analysis are crucial in getting a product that satisfies the conditions in a manufacturing process and is, in principle, directly related to the firing cycle. This research aimed at developing new formulations for the mass production of ceramic stoneware. The raw materials initially characterized were feldspar, quartz, kaolin and granite. As part of the research was developed at the University of Aveiro, in Portugal, we used two clays used in the production of Portuguese ceramics. The raw material Brazilian and Portuguese and the final product, both in Portugal and Brazil, were analyzed for X-ray fluorescence, X-ray diffraction, granulometric analysis, dilatometric analysis, thermal analysis and analysis of scanning electron microscopy (MEV). The specimens prepared at the University of Aveiro (DECV) were sintered at 10000C and 12000C and the specimens prepared in UFRN were sintered at 10000C, 10500C, 11000C, 11500C, 12000C, 12500C and 13000C, but the best results and demonstrating the presence of the mineral mullite were at temperatures of 12000C, 12500C and 13000C. The results showed that the granite waste used may be considered raw material of excellent quality for use in the ceramic industry and coating floors and more accurately by the industry of stoneware. Physical and mechanical tests conducted on samples of the formulations F01 and F02 developed in UFRN showed a water absorption and mechanical strength suitable for the stoneware
Resumo:
It is located in an area of increasing oil exploration, the region of the Lower Açu is at the mercy of a possible pollution generated by this economic activity, which includes various chemical substances harmful to health, such as metals. This thesis aims to, diagnose the areas of River Piranhas-Açu, a region of the Lower Açu, which are polluted by traces factors and more. In this study, it was determined the concentration of the chemica elements Al, CD, Cr, Cu, Fe, Mn, Ni, P, Pb, V and Zn, through the technique of ICP-OES analysis and the size of sediments and their contents organic matter. Were mapped by GPS, 12 points from collections. The interpretations of the results, together associating that allowed pollution to a possible contamination by oil activity. The results showed tha some regions have low concentrations of cadmium, lead, copper, manganese and zinc unable to promote damage to human health. However, there are places where the concentrations of certain metals chromium, iron and zinc are moderately polluted compared to the results with the reference values of literature and others that are highly polluted by iron. However, due to a greater number of wells in production in those locations, those higher concentrations, it can be suggested a possible influence of oi production in some areas with concentrations of chromium and lead are higher than the rest of the points of monitoring. Moreover, it is observed that the highest levels of metals found in sediment of finer texture and more organic matter content
Resumo:
Estuaries are environments prone to the input of chemical pollutants of various kinds and origins, including polycyclic aromatic hydrocarbons (PAHs). Anthropogenic PAHs may have two possible sources: pyrolytic (with four or more aromatic rings and low degree of alkylation) and petrogenic (with two and three aromatic rings and high degree of alkylation). This study aimed to evaluate the levels, distribution and possible sources of polycyclic aromatic hydrocarbons in the estuary of the Potengi river, Natal, Brazil. Samples of bottom sediments were collected in the final 12 km of the estuary until its mouth to the sea, where the urbanization of the Great Natal is more concentrated. Sampling was performed on 12 cross sections, with three stations each, totaling 36 samples, identified as T1 to T36. The non alkylated and alkylated PAHs were analyzed by gas chromatography coupled to mass spectrometry (GC / MS). PAHs were detected in all 36 stations with total concentration on each varying 174-109407 ng g-1. These values are comparable to those of several estuarine regions worldwide with high anthropogenic influence, suggesting the record of diffuse contamination installed in the estuary. PAHs profiles were similar for most stations. In 32 of the 36 stations, low molecular weight PAHs (with 2 and 3 ring: naphthalene, phenanthrene and their alkylated homologues) prevailed, which ranged from 54% to 100% of the total PAH, indicating that leaks, spills and combustion fuels are the dominant source of PAH pollution in the estuary. The level of contamination by PAHs in most stations suggests that there is potential risk of occasional adverse biological effects, but in some stations adverse impacts on the biota may occur frequently. The diagnostic ratios could differentiate sources of PAHs in sediments of the estuary, which were divided into three groups: petrogenic, pyrolytic and mixing of sources. The urban concentration of the Great Natal and the various industrial activities associated with it can be blamed as potential sources of PAHs in bottom sediments of the estuary studied. The data presented highlight the need to control the causes of existing pollution in the estuary
Resumo:
Caatinga is an important laboratory for studies about arthropods adaptations and aclimatations because its precipitation is highly variable in time. We studied the effects of time variability over the composition of Arthropods in a caatinga area. The study was carried out at a preservation area on Almas Farm, São José dos Cordeiros, Paraíba. Samples were collected in two 100 m long parallel transects, separated for a 30 m distance, in a dense tree dominated caatinga area, between August 2007 and July 2008. Samples were collected in each transect every 10 m. Ten soil samples were taken from each transect, both at 0-5 cm (A) and 5-10 cm (B) depth, resulting in 40 samples each month. The Berlese funnel method was used for fauna extraction. We registered 26 orders and the arthropods density in the soil ranged from 3237 to 22774 individuals.m-2 from January 2007 to March 2008, respectively. There was no difference between layers A and B regarding orders abundance and richness. The groups recorded include groups with few records or that had no records in the Caatinga region yet as Pauropoda, Psocoptera, Thysanoptera, Protura and Araneae. Acari was the most abundant group, with 66,7% of the total number of individuals. Soil Arthropods presented a positive correlation with soil moisture, vegetal cover, precipitation and real evapotranspiration. Increases in fauna richness and abundance were registered in February, a month after the beginning of the rainy season. A periodic rain events in arid and semiarid ecosystems triggers physiological responses in edafic organisms, like arthropods. Edafic arthropods respond to time variability in the Caatinga biome. This fauna variation has to be considered in studies of this ecosystem, because the variation of Arthropods composition in soil can affect the dynamics of the food web through time