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211.
ABSTRACT .A case study was performed to evaluate potential applications of desalted saline water for agriculture using 2 distillation type processes and 2 membrane type processes. The investigation determined the costs and benefits associated with desalting saline water at concentrations of 1,500, 900, 400, 200, and 50 ppm. Benefits from desalting are generated by shifts to more profitable crops, reduced costs for drainage, and reduction in fertilizer and labor requirements with better quality water. Costs are based on the project features such as desalting plants, raw water diversion facilities, storage reservoirs, conveyance and distribution systems, brine disposal, blending facilities, and gypsum addition systems. Hydrologic studies determined the crop irrigation requirements, water demand schedules, desalted water storage requirements, brine disposal requirements, and size of facilities required. Reconnaissance design layouts were made for producing desalted water using a combination of 14 schemes. The study also included a review of irrigation practices. The benefit-cost ratios range from 0.4 to 1.0 for 1,500 ppm irrigation water to 0.8 to 1.0 for 50 and 200 ppm water. Investment costs per acre are high, ranging from $12,900 to $20,900. Irrigation benefits are based on the increase in production from a desert condition with no water supply to the irrigation conditions studied.  相似文献   
212.
ABSTRACT. This study investigates economies associated with size of New England water utilities. Regression analysis techniques were applied to annual water cost and production data reported in the American Directory of Water Utilities (1968-1969). Modest economies of size in the production of water were found. Because in large communities more water is used per person, total cost increases at a slightly faster rate than population increases, but per unit costs of producing water decline. Substantial economies occurred when the number of customers was held constant and volume of water per customer increased. This study indicates possible economies when two or more of the many very small utilities combine activities to form a larger unit and by encouraging present customers to use more water.  相似文献   
213.
While the science of economics is widely used in Federal water resource development projects, the usual procedure of applying an analytical discipline to arrive at a conclusion is reversed. The “answer” is usually provided ahead of time and economics is assigned the task of justifying the preconceived conclusion. This leads to a series of mitigatory effects in which economics as a science is not allowed to freely function. This article attempts to illustrate some of these “unusual” uses of economics in Federal water projects and note the “answers” we would logically expect from the economic discipline. Even though the theory of economics is often subverted, there are positive aspects to the role of economics in evaluating Federal water projects.  相似文献   
214.
ABSTRACT Alternative combinations of water pricing and regulations are possible in allocating irrigation water. The best combination will depend on the value of water, ability to control deliveries, desire to subsidize agriculture, ownership traditions, crops grown, return flows, drainage problems, staff training, ability to collect fees, the number of farmers involved, etc. Marginal cost pricing is just one possible alternative and it is more a way of thinking about prices rather than a set system. The possibilities for achieving an equitable and efficient distribution of water are improved if some form of marginal cost pricing is included in the system of water charges.  相似文献   
215.
煤炭企业清洁生产的中/高费方案评述   总被引:1,自引:0,他引:1  
简述了煤炭企业在清洁生产审核过程中如何产生中/高费方案,分析了中/高费方案所占的比例。通过3个工程实例的分析证明,中/高费方案的实施给煤炭企业带来良好的环境效益和经济效益。  相似文献   
216.
The quality of the coral reefs in the Florida Keys is essential to sustain nature-based tourism in the Keys. The recently established marine reserves (MR) are expected to improve the reef environment, particularly coral and fish abundance and diversity. In this paper, a combined model of travel cost and contingent behavior was estimated in order to measure the non-market recreational benefits of reef quality improvements. The results indicated that an average visitor would undertake 43-80% more number of trips to the Florida Keys and experience a 69% increase in the use values per trip, as a result of the MR-induced reef quality improvements. The above non-market value estimates were further applied to evaluating alternative management proposals for funding the MR program. It was found that the annual management costs of the MR program would constitute an insignificant portion--only around one to 2%--of the annual recreational benefits that the MR would generate. The results provide a strong economic justification for designing user-based funding mechanisms in order to make the MR program self-sustaining in the future.  相似文献   
217.
废水中有机污染指标监测方法的选择   总被引:16,自引:0,他引:16  
综合考察了废水中各种有机污染物综合指标的测试对象、干扰、准确度、精确度及其分析测试技术等各种因素 ,对实现其自动化连续测量的影响。针对某些监测技术产生的严重二次污染问题 ,提出了绿色 (清洁 )监测技术的概念。文章认为在重点废水污染源安装在线监测系统实行总量控制的过程中 ,应避免使用造成严重二次污染的 CODCr在线监测仪 ,而应当采用臭氧氧化法在线监测仪 ,或其他综合指标 ,如 TOC  相似文献   
218.
我国自然资源市场体系的建立与发展   总被引:1,自引:1,他引:1  
文章以“东阳卖水—义鸟买水”这起全国首例水权交易的案例说明,必须清晰地界定自然资源的产权,同时减少有关自然资源交易过程中的费用,以尽快建立自然资源市场体系,发挥市场在配置自然资源方面的基础性作用。  相似文献   
219.
从技术角度来探讨银行的存款业务创新,提出商业银行应该考虑经济发展情况、金融文化背景等因素,以满足客户的需求为目的来设计、组织存款要素,并在市场细分的基础上,提供差别化存款产品,按市场规律进行定价。  相似文献   
220.
The Okavango Delta, the largest Ramsar wetland site, is one of the most resource-rich ecosystems in Botswana. A range of resources, including reeds, contribute in various ways to the well-being of many of the communities through subsistence and income generation. The economic value of reeds and other resources found in wetlands has been poorly understood, leading to the perception that wetlands are wastelands, and have little or no economic values. Such resources are therefore likely to receive lower priority in conservation when evaluated against other alternative activities. The aim of this research was to determine the benefit and financial and economic viability of harvesting river reed in the Okavango Delta. Primary data were collected through a structured questionnaire administered at three villages in the Okavango Delta. Secondary data were collected from existing literature. Financial and economic analysis was undertaken using static and financial models. Market prices were used to calculate the net income generated from the sale of harvested reed. The measurement criteria for static models were the annual net cash income, net annual economic benefit, and return on investment (ROI), while those under the dynamic models were the net present value (NPV), benefit cost ratio (BCR), and the net benefit investment (N/K) ratio. It was more financially profitable and economically viable to harvest and sell reeds at Shorobe village (a village relatively close to the District economic centre, Maun), than Shakawe or Etsha-13.  相似文献   
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