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31.
The effects of heavy metals, hydrocarbons, and various toxicants present in Mathura Refinery Waste Water (MRWW) on Allium cepa were examined as a model plant system. The study was based on exposure of A. cepa to different concentrations of MRWW and compared to untreated control (exposure of onion bulbs with aquaguard purified water) to determine the total protein content and activities of certain antioxidant enzymes. These enzymes were evaluated for their efficacy to serve as biomarkers of refinery waste water pollution. DNA damaging potential of MRWW was also investigated. Data demonstrated maximal enhancement in ascorbate peroxidase activity subsequent to MRWW insult, although a significant increase in activities was also noted for other enzymes in the following order: superoxide dismutase?>?glutathione-S-transferase?> catalase. This is suggestive of their potency as a biomarker of MRWW toxicity. Increase in activities of monodehydroascorbate reductase (MDHAR; 152%) and deoxyribonuclease (345%) were also found in the A. cepa system as a result of MRWW exposure. In conclusion, A. cepa system might thus serve as an appropriate tool for monitoring water pollution, especially produced by petroleum waste and heavy metals in term of induction of glutathione peroxidase, MDHAR, and deoxyribonuclease activity.  相似文献   
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Developing a compact, simple, and productive solar still is a main challenge. This paper describes a simple modification of the solar still that significantly enhances its productivity. A laboratory scale of modified single effect double slope glass solar still with the opaque triangular north wall has been developed and tested for enhancement of productivity in sunny days of the summer season in the month of April. The experiments on still have been carried out under three levels of water depths from 1 to 3 cm and compared it with the performance of conventional still of double slope single effect solar still of the same size. It is clear from the observations that opaque type still gave maximum distillate of 1793 ml at 1 cm depth of water while conventional still could produce only 1519 ml for the same depth of water. Also, for 2 and 3 cm depth of water, the opaque type still found to be more productive than conventional double slope solar still. As the former produced 1532 and 1464 ml while the latter produced 1328 and 1235 ml, for 2 and 3 cm depth of water, respectively.  相似文献   
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Data from the U.S. Environmental Protection Agency Air Quality System, the Southeastern Aerosol Research and Characterization database, and the Assessment of Spatial Aerosol Composition in Atlanta database for 1999 through 2002 have been used to characterize error associated with instrument precision and spatial variability on the assessment of the temporal variation of ambient air pollution in Atlanta, GA. These data are being used in time series epidemiologic studies in which associations of acute respiratory and cardiovascular health outcomes and daily ambient air pollutant levels are assessed. Modified semivariograms are used to quantify the effects of instrument precision and spatial variability on the assessment of daily metrics of ambient gaseous pollutants (SO2, CO, NOx, and O3) and fine particulate matter ([PM2.5] PM2.5 mass, sulfate, nitrate, ammonium, elemental carbon [EC], and organic carbon [OC]). Variation because of instrument imprecision represented 7-40% of the temporal variation in the daily pollutant measures and was largest for the PM2.5 EC and OC. Spatial variability was greatest for primary pollutants (SO2, CO, NOx, and EC). Population-weighted variation in daily ambient air pollutant levels because of both instrument imprecision and spatial variability ranged from 20% of the temporal variation for O3 to 70% of the temporal variation for SO2 and EC. Wind  相似文献   
35.
A statistical methodology formulated for defining background or baseline levels of constituents of concern in groundwater is presented. The methodology was developed for the case where prior delineation of unimpacted areas is not possible because of site history and a large set of groundwater monitoring measurements exists. Consideration was given to spatial and temporal trends, outliers, and final segregation of wells into impacted or unimpacted categories to develop probability distributions and summary statistics for each constituent evaluated. The formulated approaches were applied to groundwater monitoring data for the U.S. Department of Energy Savannah River Site facility, and results for four representative constituents (aluminum, arsenic, mercury, and tritium) are discussed.  相似文献   
36.
Geographic Information System (GIS) is used to develop the Oceanographic Information System (OIS) for marine environmental data off Karnataka coast. Its goal is to provide a set of tools for oceanographic and bathymetry data assessment and products like graphs, query system for the users. The most significant interfaces are the GIS based Map-query and Contour visualization. The interfaces are user-friendly and oriented towards bridging the gap between user's knowledge and the technical knowledge required to operate the software system. The OIS also provides users with other analysis tools like query based reports and graphs. OIS can be used as a powerful tool to synthesize not only all the data off Karnataka coast but for comprehensive interpretation and forecasting of marine environmental ecosystems for any region. This system has been applied to the Karnataka Coastal Environment, India and it is very useful for the clients and policy makers.  相似文献   
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The contemporary copper cycle of Asia   总被引:11,自引:1,他引:10  
A regional stock and flow model for an industrial metal was developed based on the substance-flow framework. Using this model, the contemporary copper cycle of the Asian region was constructed by aggregating country-level production and import and export data for different stages of the copper cycle. The reliability and availability of data were assessed both qualitatively and quantitatively. Asia as a region is a net importer of copper. There is a significant build-up of copper in use at a rate of nearly 3TgCu/year. The per capita generation of copper waste (0.4kgCu/(capita-year)) and the rate of secondary recovery of copper are low compared with Europe and North America. Japan's rates of use, waste generation, and recycling of copper are all much larger than the continental average. A tremendous potential exists in the region to utilize the copper content of the in-use reservoir, and subsequently to enhance copper recycling rates in the future. A set of metrics for the copper cycle is suggested in order to address sustainability issues related to resource policy and the environmental management of copper.  相似文献   
39.
A comparison of air quality data obtained at a downtown roof top location, a surburban area, a main road curbside and adjacent to a major highway was conducted. The results of this study revealed that a reasonably good correlation between daily average concentrations at these locations can be established. For primary pollutants it was found that within the immediate release zone their average concentration is 3.5 to 4.0 times higher than at a close location but at roof top level. Total suspended particulate (TSP) concentration was found to increase by about 80%, and O3 is reduced by about 25%. No significant difference was obtained between daily averages obtained at the city center location and the suburb site 5 km away.  相似文献   
40.
Monitoring of atmospheric lead from the Dalbergia sissoo treewas undertaken at Lucknow urban centre of the Ganga Plain, India.Atotal of 26 leaf samples were collected in spring, monsoon and winter seasons from 16 sampling sites and was analysed by Atomic Absorption Spectrophotometry method. Lead concentrations were low in spring season, increased in monsoon to winter seasons and range from 2.1 to 28.2 μg/g (dry wt.). This accumulative response of lead in the tree leaves is directly linked with the exposure time of automobile emission that is considered to be the predominant source for it. Highway localities show higher lead concentrations by a factor of 2 as compared to urban localities. Highest concentration was recorded at Sitapur Road (National Highway No. 24) in winter season. A linear quantitative relationship between urban air-lead levels and lead-in-the Dalbergia sissoo leaves is used to infer the qualitative assessment of present day atmospheric lead pollution. Reported results suggest a drastic reduction in mean lead concentration in Lucknow urban air from 1.32μg/m3 in 1994 to 0.19μg/m3 in 2002. Similarly, mean lead concentration in the tree leaves during winter season also dropped from 17.9 μg/g in 1994 to 8.1 μg/g in 2004. Despite of increasing urban population, urban area, vehicle population and traffic density, the introduction of unleaded-petrol (vehicular fuel) keeps lead level in the urban environment of Lucknow much lower than the past. Like Lucknow, other urban centres of the Ganga Plain are also on way to the exponential increase in pressure of urbanization. An appropriate urban public transport planning is required to provide healthy atmospheric environment for millions of people especially future young generation.  相似文献   
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