Chemical process safety was not a major public concern prior to 1984. As far as chemical hazards were concerned, public fears focused on disease (cancer) and environmental degradation. Even a series of major process incident tragedies did not translate into widespread public concerns about major incidents in chemical plants that might disastrously affect the public. This situation changed completely after the December 1984 disaster at the Union Carbide plant in Bhopal. Not only was the public's confidence in the chemical industry shaken, the chemical industry itself questioned whether its provisions for protection against major incidents were adequate.
The recognition of the need for technical advances and implementation of management systems led to a number of initiatives by various stakeholders throughout the world. Governments and local authorities throughout the world initiated regulatory regimes. Has all that has resulted from the legacy of Bhopal reduced the frequency and severity of incidents? How can we answer this question? As we move into more and more globalization and other complexities what are the challenges we must address? According to the authors, some of these challenges are widespread dissemination and sharing of lessons learned, risk migration because of globalization, changing workforce, and breakthroughs in emerging areas in process safety. 相似文献
Environment, Development and Sustainability - Torrents are ephemeral streams which usually carry heavy bedload and flash flows. The frequent changes in its course caused by meandering and migration... 相似文献
The composition and successional status of a forest affect carbon storage and net ecosystem productivity, yet it remains unclear whether elevated atmospheric carbon dioxide (CO2) will impact rates and trajectories of forest succession. We examined how CO2 enrichment (+200 microL CO2/L air differential) affects forest succession through growth and survivorship of tree seedlings, as part of the Duke Forest free-air CO2 enrichment (FACE) experiment in North Carolina, USA. We planted 2352 seedlings of 14 species in the low light forest understory and determined effects of elevated CO2 on individual plant growth, survival, and total sample biomass accumulation, an integrator of plant growth and survivorship over time, for six years. We used a hierarchical Bayes framework to accommodate the uncertainty associated with the availability of light and the variability in growth among individual plants. We found that most species did not exhibit strong responses to CO2. Ulmus alata (+21%), Quercus alba (+9.5%), and nitrogen-fixing Robinia pseudoacacia (+230%) exhibited greater mean annual relative growth rates under elevated CO2 than under ambient conditions. The effects of CO2 were small relative to variability within populations; however, some species grew better under low light conditions when exposed to elevated CO2 than they did under ambient conditions. These species include shade-intolerant Liriodendron tulipifera and Liquidambar styraciflua, intermediate-tolerant Quercus velutina, and shade-tolerant Acer barbatum, A. rubrum, Prunus serotina, Ulmus alata, and Cercis canadensis. Contrary to our expectation, shade-intolerant trees did not survive better with CO2 enrichment, and population-scale responses to CO2 were influenced by survival probabilities in low light. CO2 enrichment did not increase rates of sample biomass accumulation for most species, but it did stimulate biomass growth of shade-tolerant taxa, particularly Acer barbatum and Ulmus alata. Our data suggest a small CO2 fertilization effect on tree productivity, and the possibility of reduced carbon accumulation rates relative to today's forests due to changes in species composition. 相似文献
Summary Enzootic bovine haematuria (EBH) is a disease of cattle characterised by intermittent presence of blood in their urine and tumours of mixed origin in the urinary bladder. No consensus exists on the etiology of the disease, though bracken fern (Pteridium aquilinum) and/or papilloma virus have been implicated. There are areas where the malady is absent but the putative incrementing factor(s) are present. This raised the possibility of investigations into the interplay of environmental factors which might be conducive to the possible exposures to carcinogens in some regions. A comparative study of areas where the disease is prevalent (enzootic), and where it is absent (nonenzootic), to determine the type of vegetation (including ferns), the grazing patterns, the animal husbandry practices and the agroclimatic conditions in animal-plant interaction, is presented. Most of the ferns are common to both enzootic and nonenzootic areas. Bracken fern, a known source of carcinogens is present in both enzootic and nonenzootic areas. Ferns, with the exception of Athyrium spp. are not acceptable to the cattle when offered, being smelt and rejected. Ferns are not used as bedding material in the enzootic area studied.The authors conclude that different environmental conditions and animal husbandry practices may result in the cattle in the enzootic areas being exposed to carcinogenic brackens and other ferns at a time when there is a shortage of other alternative feedstuffs.Drs Dawra, Sharma and Krishna work at the Palampur Regional Station of the Indian Veterinary Research Institute. Correspondence should be addressed to Dr Rajinder K. Dawra. 相似文献
The significant progress made during the UN International Water Decade is reviewed, eight years after its inception in 1981. Major issues remain, especially in rural areas. The advantages of an integrated water resource planning framework (IWRP) are explained, including the use of this process to develop a flexible strategy for the water and sewerage sector to meet national policy objectives. Economic efficiency in supply implies optimal service quality and least cost planning, while efficient pricing policy requires the implementation of long-run marginal cost based tariffs. Better sector organization, management, accountability, options for decentralization and innovative financing methods are also discussed. 相似文献
Various options are applicable for the removal of water pollutants included reverse osmosis, ion exchange, coagulation, co-precipitation, catalytic reduction, herbal filtration, electrodialysis and adsorption. This paper deals with the sorption phenomena for the removal of pollutants from drinking water. Attempts have been made to use low cost sorbents developed by pretreatment/activation/impregnation with alkalis, acids, iron oxide, manganese dioxide, ferric chloride, alum, lime, aluminum salts with natural products/indigenous minerals viz. activated alumina, activated carbon, groundnut husk, saw dust, chemically coated sand, fly ash, zeolites, clay minerals and other plant products. Application of Freundich and Langmuir isotherms were used to assess the adsorption capacity. Equilibrium isotherms were determined at optimum temperature and pH to characterize the sorption process. Statistical parameters such as mass transfer coefficients, multiple regression analysis were applied to establish the mechanism. It is suggested that the characterization of suitable, and exhausted sorbent through the application of fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray fluorescence (XRF) is essential to establish its surface bonding. Scope for safety evaluation and risk assessment to human and biosphere may provide the guideline and predication to the regulatory agencies for its sustainable use and safe disposal The ecotoxicological assessment of the leachates and low cost removal technology are discussed in this paper. 相似文献