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911.
ABSTRACT: Law and hydrology are inextricably woven together in the pattern of water resource development in the west. The former attempts to allocate a limited and valuable resource as the latter tries to define the limits of the resource. In the past an inadequate data base has made hydrologic estimates difficult and political factors have pushed the law into possibly conflicting commitments in the Colorado River Basin. Through the use of tree-ring research, hydrologists have produced a more definitive data base and placed water allocations such as the Colorado River Compact of 1922 in a clearer long-term perspective. This data base leads to the conclusion that the surface-water supply is about 13.5 million acre-feet per year. This hydrologic limit must be apportioned within an existing legal framework - the “Law of the River.” As development approaches the resource limit in the Upper Colorado River Basin, lawyers and hydrologists must act in concert toward the equitable solution of allocation and reallocation problems.  相似文献   
912.
During 1976, Illinois experienced a mild drought, of i ntensity equivalent to the once in 5 years frequency. It was anticipated that the drought would result in deteriorated water quality because dilution of point source discharges would be diminished. Furthermore, because productivity in Illinois streams is light limited, reduced runoff should result in clearer streams, higher algae levels, and greater variability in dissolved oxygen levels. In spite of these expectations, both chemical and biologic data showed that water quality in 1976 was appreciably better than that before 1975. The information provided by the Illinois water quality index (Janardan and Schaeffer 1977) coincides with biologic analyses of benthic invertebrates. The index supports and supplements the biologic data and provides a means for quantifying and integrating chemical and biologic data.The results of this study showed that the drought had little, if any, effect on statewide water quality. Although the magnitude of the drought varied across the state, water quality remained unchanged between 1975 and 1976. This may have reflected the ability of unpolluted systems to adjust to natural variations or have been an indication that there were offsetting statewide gains in pollution control in 1976 or that uncharacterized, broad-based phenomena were operating in stream ecology, or that combinations of these were in effect.Based on presentations before the American Water Resources Assocition, Illinois Section, Chicago, Illinois, June 10–11, 1977.  相似文献   
913.
ABSTRACT: A mathematical programming model is proposed to determine economically efficient urban water resource allocation and pricing policy by maximizing the sum of the consumer and producer surplus. The optimization of this nonlinear problem is accomplished by the use of linear programming algorithm. The feasibility of using recycled water for municipal purposes is examined in a planning context. The impact of higher water quality discharge standards on pricing and allocation of water is analyzed and the attractiveness of water reuse option is demonstrated.  相似文献   
914.
Abstract

This paper describes the development of apparatus suitable for direct supercritical fluid extraction of organics from water. Results are presented for the extraction of pentachlorophenol present in water at concentrations of the order of 0.1 ppm. The effect of changes in apparatus design and supercritical fluid flow rate on recovery are discussed.  相似文献   
915.
易燃液体燃烧痕迹识别对助燃剂放火火灾调查至关重要。选用丙纶地毯和PVC地板革作为纤维和塑料地板的代表,以工业酒精作为易挥发助燃剂的代表,研究酒精用量、灭火方式等对燃烧痕迹形成及痕迹稳定性的影响。通过与未加载酒精的痕迹对比,发现丙纶地毯因热稳定性较差,燃烧后往往能形成烧坑或烧洞,其燃烧轮廓以典型的灰化形式存在,加载酒精的部位熔融严重,与地面紧紧粘连在一起;PVC地板革因为表面光滑,酒精在其表面不断流淌,燃烧后会留下清晰的轮廓,类似于细线状的印痕,而地板革本身基本不会燃烧。燃烧熄灭的方式也会对其炭化程度、燃烧图痕、残余形状产生影响。  相似文献   
916.
Water samples were collected in the Northeast Atlantic Ocean (33-37° N and 11-16° W) in May 1983, and vertical profiles of chemical and physical parameters allowed us to identify the different water masses. A significant difference in salinity and its maximum can be found at different places and depths, as a consequence of the spreading of the Mediterranean Water (MW) from the Strait of Gibraltar. The apparent oxygen utilization shows a correlation with nutrients in North Atlantic Central Water. The relative percentages of water masses were assessed in order to examine the depth of maximum influence of MW as a function of latitude and to apply this knowledge to the black scabbard fish long-line strategy. The long-line fishing depth location was adapted to the specific MW distribution of the different banks with improvements in the mean catch efficiency. The thickness of the MW prevalence layer has a pronounced decrease to the south. MW influence clearly sinks and decrease to south-west. The highest percentage of the MW was found in the Gorringe Bank area and the lowest in the Madeira area.  相似文献   
917.
We propose a suite of actions for strengthening water governance in contexts with complex, multi-tiered arrangements. In doing so, we focus on the collective water policies and approaches of the United Kingdom (UK), including those of devolved governments, which confront a host of serious water-related challenges—from massive flooding of urban areas and agricultural lands, to pressure on aquifers from rising water demand and drought. Further complexity in addressing these challenges has emerged in the wake of the June 2016 vote to leave the European Union (EU), so-called ‘Brexit’, and the ensuing ‘separation process’ with uncertainties for institutional and governance arrangements to follow. We make ten proposals for improving and reinvigorating water policy in complex, multi-layered situations, and comment specifically on their application in the UK setting. These are: put in place a system-wide water policy; fully embrace community-led nested river basin planning and management; fully fund river basin planning and management; re-focus the policy framing; use best-available data and information; create conversational spaces and become a more water-literate society; mobilise people; support and sustain core community networks; underpin river basin plans with regulatory provisions and effective monitoring and enforcement; and address systemic institutional amnesia. Individually and collectively, we contend that these actions will have a marked effect on transforming the planning and management of water resources. A system-wide water policy that maintains and builds on the substantive biophysical and socio-economic benefits delivered through implementation of the EU Water Framework Directive, together with the more recent Floods Directive, will galvanise stewardship of water in the UK. We urge more active engagement with and empowerment of the multiplicity of system ‘actors’, and highlight the role of non-government actors in a post-Brexit world as conduits for reaching out to and connecting directly with a wide range of water-related actors, especially across the EU. While attention to-date has focused on a plethora of specifically water-related projects, initiatives, plans and regulations, what is really needed is a systemic, long-term view of water resource management.  相似文献   
918.
民用压缩气体和液化气体一旦发生爆炸,会造成很大的破坏力。根据压缩气体和液化气体的特性,通过计算,由爆炸中心到能保证人身安全和建筑(构筑)物和设备免遭破坏的最小距离。  相似文献   
919.
我国安全生产的形势和任务   总被引:10,自引:0,他引:10  
论述了我国安全生产工作发展概况与安全的关系 ,分析了我国安全生产状况 ;指出了我国安全生产面临的主要难点 ;提出了我国安全生产工作的重任所在 ;笔者认为 ,只要从实际出发 ,坚持改革、标本兼治和技术创新 ,发挥政府、企业、劳动者三方协调机制的作用 ,借鉴和吸收国际成功经验 ,我国安全生产水平是会列于世界先进行列的。  相似文献   
920.
重点论述社会主义市场经济条件下的企业全员安全管理的概念、特点和基本要求,企业开展全员安全管理的重要性,应遵循的原则和实施措施。  相似文献   
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