969 resultados para explosive ordnance disposal


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Different geoenvironmental site investigation techniques to assess contamination from a municipal solid waste disposal site in Brazil are presented here. Superficial geophysical investigation (geoelectrical survey), resistivity piezocone penetration tests (RCPTU), soil samples collected with direct-push samplers and water samples collected from monitoring wells were applied in this study. The application of the geoelectrical method was indispensable to identify the presence and flow direction of contamination plumes (leachate) as well as to indicate the most suitable locations for RCPTU tests and soil and water sampling. Chemical analyses of groundwater samples contributed to a better understanding of the flow of the contaminated plume. The piezocone presented some limitations for tropical soils, since the groundwater level is sometimes deeper than the layer which is impenetrable to the cone, and the soil genesis and unsaturated conditions affect soil behavior. The combined interpretation of geoelectrical measurements and soil and water samplings underpinned the interpretation of RCPTU tests. The interpretation of all the test results indicates that the contamination plume has already overreached the landfill's west-northwest borders. Geoenvironmental laboratory test results suggest that contamination from the solid waste disposal site has been developing gradually, indicating the need for continuous monitoring of the groundwater.

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The problems caused by the residual effluents of wine distilleries for alcohol production are well known. The effluent effects in soil and groundwater are being researched in an area with sugar cane culture which receives, yearly, vinasse by dispersion. Samples are being collected from the soil, the groundwater and the existing creeks in the area. Four sub-areas are being monitored separately with a vinasse application of 300 m 3/ha year. Experimentation periods in each area have been 0, 5, 10 and 15 years. In the unsaturated zone, samples are being collected at depths of 25, 75 and 150 cm. The chemical analyses include macro and micro nutrients, organic matter and pH. Physical analyses give the soil water retention, hydraulic conductivity and soil particle distribution. These measurements permit the evaluation of nitrogen absorption and fertility changes of the soil. A tendency for the maintenance of soil fertility can be observed but with an elevation of nitrate concentration in groundwater.

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Groundwaters and surface waters from an area of treatment of sand for industrial purposes at Analandia municipality, nearly in the center of Sao Paulo State, Brazil, were chemically and isotopically analyzed with two aims: to evaluate if the anthropogenic activities that has taken place for the last 6 years is affecting the quality of the hydrological resources and to relate the hydrogeochemical behaviour of the uranium isotopes 234U and 238U with the pattern of circulation of groundwaters.

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This investigation reports the results of a study realized in an area related to the development of sand mining activities, which belongs to Sibelco Mineração Ltd. The site is located around Analândia municipality, nearly in the center of São Paulo State, Brazil. Hydrochemical analyses of groundwater were realized under different periods of time, with the aim of evaluating the possibility of release of several constituents to the liquid phase, which may be a source of pollution of the surface hydrological resources and of the deeper Guarani aquifer. This is because the site is located at the recharge area of Guarani aquifer and some tributaries from Corumbataí river may also be suffering contamination, implying on the impoverishment of the water quality that are very important resources in the region, as they are extensively used for drinking purposes, among others.© 2011 WIT Press.

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

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Sciaenids are fish which are normally abundant in tropical estuaries of the western Atlantic. Studies on the Caeté river estuary in the northern Brazilian state of Pará have revealed that in this area Sciaenidae is the dominant family, comprising almost 50% of all teleosts sampled. In this paper we present the results of the first phylogenetic study on South American estuarine sciaenids, during which we obtained mitochondrial gene 16S sequences from 15 species belonging to eight genera occurring in the Caeté estuary. Intergeneric nucleotide divergences varied from 5 to 15%, Lonchurus and Menticirrhus being the most divergent lineages. Nucleotide divergences were quite variable amongst species of the same genus, ranging from 1.2% (Stellifer microps x Stellifer naso) to 8.4% (Menticirrhus americanus x Menticirrhus littoralis). Cladograms based on maximum parsimony, minimum evolution and maximum likelihood depicted an explosive diversification pattern for the western Atlantic sciaenid assemblage. Our analysis further reveals a very close relationship between Bairdiella and Stellifer, a monophyletic clade which emerged during the more recent diversification events of the Sciaenidae family. The phylogenetic reconstruction suggests the need for a revision of the taxonomy and nomenclature of the Bairdiella/Stellifer group.

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

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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When the well "goes dry" or when the windmill or pump breaks down, every one in the household immediately appreciates the value fo plenty of water. In other words, "You never miss the water until the well runs dry." Fortunately, in most sections of this state, plenty of pure water may be obtained by sinking wells of moderate depth, yet surprisingly few farm homes are supplied with running water in the kitchen even though the barn yards are equipped with hydrants and tanks. It is the purpose of this bulletin to present a number of water supply and sewage disposal systems which have been used in Nebraska and surrounding states and which add greatly to the comfort and convenience of the farm home.

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This paper deals with the emergence of explosive synchronization in scale-free networks by considering the Kuramoto model of coupled phase oscillators. The natural frequencies of oscillators are assumed to be correlated with their degrees, and a time delay is included in the system. This assumption allows enhancing the explosive transition to reach a synchronous state. We provide an analytical treatment developed in a star graph, which reproduces results obtained in scale-free networks. Our findings have important implications in understanding the synchronization of complex networks since the time delay is present in most real-world complex systems due to the finite speed of the signal transmission over a distance.

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A contaminated site from a downstream municipal solid waste disposal site in Brazil was investigated by using a 3D resistivity and induced polarization (IP) imaging technique. This investigation purpose was to detect and delineate contamination plume produced by wastes. The area was selected based on previous geophysical investigations, and chemical analyses carried out in the site, indicating the presence of a contamination plume in the area. Resistivity model has successfully imaged waste presence (rho < 20 Omega m), water table depth, and groundwater flow direction. A conductive anomaly (rho < 20 Omega m) outside wastes placement was interpreted as a contamination plume. Chargeability model was also able to imaging waste presence (m > 31 mV/V), water table depth, and groundwater flow direction. A higher chargeability zone (m > 31 mV/V) outside wastes placement and following conductive anomaly was interpreted as a contamination plume. Normalized chargeability (MN = m/rho) confirmed polarizable zone, which could be an effect of a salinity increase (contamination plume), and the clay presence in the environment.

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The purpose of this work is to analyze the parasitological risks of treated wastewater reuse from a stabilization pond in the city of Piracicaba, in the State of Sao Paulo (Brazil), and the level of treatment required to protect public health. Samples were taken from raw and treated wastewater in stabilization ponds and submitted to a parasitological, microbiological and physicochemical analysis. The study revealed on treated wastewater the presence of Ascaris sp. and Entamoeba coli with an average density of 1 cysts L-1 and 6 eggs L-1, respectively. For Ascaris, the annual risks of infection due to the accidental ingestion of wastewater irrigation were 7.5 x 10(-2) in 208 days and 8.7 x 10(-2) in 240 days. For Total Coliforms and Escherichia coli in treated wastewater, the average density was 1.0 x 10(5) MPN/100 ml and 2.7 x 10(4) MPN/100 ml respectively, representing 99% and 94% removal efficiency, respectively. For BOD, COD, TS and TSS removal efficiency was 69, 80, 50 and 71%, respectively. The removal efficiency for nitrogen; ammonia nitrogen and total phosphate was 24, 19 and 68%, respectively. The average density of helminths eggs in treated wastewater is higher compared to the density of the limit value of <= 1 egg L-1 and tolerable risk is above the level recommended by the World Health Organization. Multiple barriers are necessary for the reduction of organic matter, chemical contaminants and parasites from treated wastewater. Standards for the sanitary control of treated wastewater to be reused in agricultural irrigation areas should be compiled for developing countries in order to minimize public health risks.

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Expired or unused medication at people's homes is normally disposed of in normal garbage, sewage system or, in certain cases, returned to the public health system. There is still no specific legislation regarding this leftover medication to regulate and orient the handling and correct disposal of medication waste. However, there is defined regulation regarding health services' solid waste. This article has the objective of discussing management models for the disposal of medication waste and the recommendations made by pertinent national and international legislation. By means of literature reviews, the management structure for medication waste of international legislation and the regulations regarding the environment, as well as the national legislation for the solid waste from health services was analyzed. Through the analysis it was possible to present better clarifications as to the possible impacts to the environment, to the public's health and alternatives in order to obtain the efficient disposal of medication, reducing and/or avoiding sanitary risk, guaranteeing the quality and safety of public health.

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An explosive synchronization can be observed in scale-free networks when Kuramoto oscillators have natural frequencies equal to their number of connections. The present paper reports on mean-field approximations to determine the critical coupling of such explosive synchronization. It has been verified that the equation obtained for the critical coupling has an inverse dependence on the network average degree. This expression differs from those whose frequency distributions are unimodal and even. In this case, the critical coupling depends on the ratio between the first and second statistical moments of the degree distribution. Numerical simulations were also conducted to verify our analytical results.