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81.
Analyzing historical databases can provide valuable information on the incident occurrences and their consequences for assessing the safety of the chemical process industry. In this study, the RMP and HSEES databases were utilized to understand the patterns and the factors influencing chemical process industry incidents. Frequency exceedance curves were generated by utilizing the different incident consequences from the databases to understand the profile of societal loss from reported incidents. Understanding the statistics and trends of the historical incidents could serve as important lagging indicators in order to assess the probable proximity to major consequences from the low-probability/high-consequence incidents. To this regard, the safety pyramids were also generated to better understand the relationship between the different consequences of the reported incidents. Furthermore, the safety pyramids were analyzed in comparison with the traditional safety pyramid proposed by Heinrich to understand the US process industry incident occurrence trends.  相似文献   
82.
Ashtamudi estuary, situated on the southwest coast of India, is enormously affected by anthropogenic interventions. Physicochemical quality of water and sedimentological features of the estuary are evaluated during monsoon and nonmonsoon seasons to elucidate its quality variations and to link the same with existing environmental scenario. The whole data has been factorized using principal component analysis for extracting the total variability and linear relationships existing among a set of different physicochemical parameters of the backwater system. In PCA, high loadings were obtained for conductivity, salinity, fluoride, calcium, magnesium, sulfate, boron, and pH. The results were revealed that all the physicochemical processes depend upon seasonal fluctuation of freshwater input and seawater intrusion. Wide spatial concentration fluctuations of organic carbon and iron in bottom sediment have been noticed and both constituents reveal good correlation with sediment texture. The results showed high deterioration of the physicochemical quality of water during nonmonsoon season with respect to monsoon season.  相似文献   
83.
The potential threat of emerging chemicals to the aquatic flora is a major issue. The purpose of the study was to develop a multispecies microalgae test in order to determine the impact of species interactions on the cytoxicity of an emergent toxic contaminant: the tetrabromobisphenol A (TBBPA). Single and multi-species tests were thus performed to study the effects of this flame retardant on two microalgae (Pseudokirchneriella subcapitata and Nitzschia palea) commonly observed in freshwater. A synthetic medium was designed to allow the growth of both species. The algae were exposed to 1.8, 4.8, 9.2, 12.9 and 16.5 μM of TBBPA for 72 h. After staining with fluorescein diacetate (FDA), viable cells of each alga species were analyzed by flow cytometry based on chlorophyll autofluorescence and intracellular esterase activity. Density and abundance of viable cells were assessed to follow the population growth and the cell viability. In TBBPA treated samples, the growth of the two microalgae was significantly inhibited at the three highest concentrations (9.2, 12.9 and 16.5 μM) in the two tests. At the end of the experiment (t = 72 h), the cell viability was also significantly smaller at these concentrations. The decreases of growth rate and viable cell abundance in TBBPA treated populations of N. palea were significantly higher in multi-species test in comparison with the single-species test. No significant differences were noticed between the two tests for P. subcapitata populations exposed to TBBPA.  相似文献   
84.
Environmental Science and Pollution Research - The detailed analyses of the water balance components (WBCs) of the catchment help assess the available water resources, especially in the arid...  相似文献   
85.
The objective of this experiment is to study the potential ability of Salvinia natans L. to use in phytoassay for the cadmium toxicity in ecotoxicological studies. It is a simple and cost competitive method. The sensitivity of S. natans in terms of biochemical changes and enzyme activities to Cd2+ was remarkably noticeable. The catalase and protease activity was significantly decreased in the presence of cadmium, with increase of peroxidase and superoxide dismutase activity. The level of protein, carbohydrate and chlorophyll decreased and proline content increased in plants. The maximum permissible concentration of cadmium in different general water quality standards was evaluated and found that cadmium standard is not stringent enough.  相似文献   
86.
This communication presents the results of an investigation conducted on color removal from a monoazo acid dye, C.I. Acid Red 88, by adsorption onto coal based sorbents like Lignite coal, Charfines and Bituminous coal and F-400 Activated carbon and by chemical coagulation employing Aluminum sulfate, Ferric chloride, Manganese sulfate, Manganese chloride and Barium chloride.  相似文献   
87.
Eco-industrial networking is considered as a new approach for businesses to improve their competitiveness, economic viability and human and ecosystem health. A cyclic material flow with alternative usage of all materials in the loop is an essential feature of an eco-industrial network. While eco-industrial networking has been primarily applied on the high-tech sector, this paper attempts to apply the principles on the fishery sector of An Giang, a Vietnamese province in the Mekong River Delta. An Giang Province has its own market share in the trade of Tra and Basa fish. The industries in the value chain of Tra and Basa are in a situation that forces them to improve their competitiveness to retain the market share. It was found that forming an eco-industrial network and recruiting new businesses to utilize all materials in the process provides additional revenue apart from reducing waste disposal concerns. This paper details the current market situation, the issues faced and material flow patterns and presents a feasible eco-industrial network. The results of the study indicate that the eco-industrial network creates positive impacts in terms of increased competitiveness, improved socio-economic conditions and cleaner environment.  相似文献   
88.
Starting with the intensification of irrigation activities in the beginning of 1980s in Abaya and Chamo lakes area, the decreasing water inflow to the lakes caused denudation of the wetlands. The ecological situation in the lake region changed significantly during last four decades. The lakes and associated wetlands change have been studied using Landsat MSS (1973), Landsat TM (1986), and Ladsat ETM (2000) satellite imagery. Along with satellite imagery, other hydro-meteorological data were collected and hydro-meteorological data analyses were done to assess the variability of wetlands. From these data, lakes morphometric property estimation at different time series and water balance analysis for both lakes were done. Wetlands are mapped from the TCT image and these maps are subject to change detection to see the temporal and spatial variability of the wetlands. Moreover, the lake-morphometric area and volume variation have been studied. The result showed that between 1986 and 2000, a significant reduction has been observed but lesser than the previous decades (6.4 km(2)). The identified reason behind this change is that the free settlement and shoreline cultivation of the wetlands causing the soil erosion and eventually adds the sediment to the wetlands.  相似文献   
89.
Environmental Science and Pollution Research - Polyvinylidene fluoride (PVDF) blended with varying concentrations of titanium nanotubes (TNT) was electrospun to result in a nanocomposite filter...  相似文献   
90.
Environmental Science and Pollution Research - The present work aims to investigate seasonal variations in air pollution levels in Lucknow and assess the ambient air quality of the city together...  相似文献   
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