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181.
182.
The Clutha is the largest river in New Zealand. The last two decades have witnessed major conflicts centered on the utilization of the water resources of the upper Clutha river. These conflicts have by no means been finally resolved. The focus of this article is on institutional arrangements for water resource management on the Clutha, with particular reference to the decision-making processes that have culminated in the building of the high dam. It critically evaluates recent experiences and comments on future prospects for resolving resource use conflicts rationally through planning for multiple utilization in a climate of market led policies of the present government.The study demonstrates the inevitable conflicts that can arise within a public bureaucracy that combines dual responsibilities for policy making and operational functions. Hitherto, central government has been able to manipulate the water resource allocation process to its advantage because of a lack of clear separation between its two roles as a policy maker and developer. The conflicts that have manifested themselves during the last two decades over the Clutha should be seen as part of a wider public debate during the last two decades concerning resource utilization in New Zealand. The Clutha controversy was preceded by comparable concerns over the rising of the level of Lake Manapouri during the 1960s and has been followed by the debate over the think big resource development projects during the 1980s.The election of the fourth Labour government in 1983 has heralded a political and economic policy shift in New Zealand towards minimizing the role of public intervention in resource allocation and major structural reforms in the relative roles of central and regional government in resource management. The significance of these changes pose important implications for the future management of the Clutha.  相似文献   
183.
High performance sorbents for flue gas desulfurization can be synthesized by hydration of coal fly ash, calcium sulfate, and calcium oxide. In general, higher desulfurization activity correlates with higher sorbent surface area. Consequently, a major aim in sorbent synthesis is to maximize the sorbent surface area by optimizing the hydration conditions. This work presents an integrated modeling and optimization approach to sorbent synthesis based on statistical experimental design and two artificial intelligence techniques: neural network and genetic algorithm. In the first step of the approach, the main and interactive effects of three hydration variables on sorbent surface area were evaluated using a full factorial design. The hydration variables of interest to this study were hydration time, amount of coal fly ash, and amount of calcium sulfate and the levels investigated were 4-32 h, 5-15 g, and 0-12 g, respectively. In the second step, a neural network was used to model the relationship between the three hydration variables and the sorbent surface area. A genetic algorithm was used in the last step to optimize the input space of the resulting neural network model. According to this integrated modeling and optimization approach, an optimum sorbent surface area of 62.2m(2)g(-1) could be obtained by mixing 13.1g of coal fly ash and 5.5 g of calcium sulfate in a hydration process containing 100ml of water and 5 g of calcium oxide for a fixed hydration time of 10 h.  相似文献   
184.
Polybrominated diphenyl ether (PBDE) concentrations were measured in surficial sediments from coastal sediments receiving industrial and municipal effluents in Kuwait. The summation PBDE concentrations varied by two orders of magnitude ranging from 80 to 3800 pg g(-1)dw. The congener distribution was dominated by BDE 183, with minor contributions from BDEs 154 and 153. The similarity between the congener profile to that of the technical octa formulation (Bromkal 79-8DE) suggests a source of this product in Kuwait. The observed gradient in concentration distribution, with high summation PBDE concentrations near the shore and an exponential decrease seaward, indicates that wastewater discharge from industrial activities in the study area is the primary source of these compounds in the sediments.  相似文献   
185.
Work-related accidents are considered as a major health problem worldwide. The aim of present study was to determine the epidemiological pattern of occupational accidents among workers insured by the Iranian Social Security Organization (ISSO) between 2001 and 2005.Subjects consisted of all workers and drivers who had a work-related accident during 2001–2005 and were registered in the Iranian Social Security Organization (ISSO) database according to the inspection reports. An ordinal logistic regression model (proportional odds regression model) was used to assess the concurrent effects of independent variables on accident outcomes.Overall, 86,437 work-related accidents were investigated. The accidents were more frequent in metal workplaces and electrical industries, respectively. More than half of the accidents were due to incautious activities. Workers’ age (age at the time of accident) (OR = 0.99, CI: 0.989–0.994), gender (OR = 1.3, CI: 1.191–1.683), marital status (OR = 1.25, CI: 1.143–1.675) as well as accident setting (OR = 1.88, CI: 1.728–1.975) had significant effect on accident outcomes. Pattern of occupational injuries in Iran was consistent with the global pattern for accident outcomes.  相似文献   
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187.
Environmental Chemistry Letters - Thermodynamic parameters ΔG°, ΔH° and ΔS° are indicators of the possible nature of adsorption. This review summarizes the...  相似文献   
188.
Environmental Science and Pollution Research - Arsenic (As) indelibly exists in the environment and may reach to a food chain. Flavors and herbs are recognized sources of natural antioxidants that...  相似文献   
189.
Environmental Science and Pollution Research - This study aimed to investigate the effect of exposure to pesticides and the prevalence of type 2 diabetes (T2D). In a cross-sectional study with a...  相似文献   
190.
Environmental Science and Pollution Research - The aim of this study is to describe the existence of the inflammatory marker nuclear factor kappa light chain B lymphocyte protein (NF-?B P65)...  相似文献   
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