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981.
ABSTRACT: Major parameters and optimum storage volumes of rooftop rain water harvesting systems (RRWHSs) have not been investigated in detail in Taiwan. Accordingly, the four major parameters of RRWHSs were herein identified and elucidated using a simulation method. Because the performance of the RRWHSs is sensitive to the runoff coefficient, a field experiment was conducted to determine the runoff coefficient more precisely for various types of roofs. A simulation model including production theory was developed and employed to estimate the most cost effective combination of the roof area and the storage capacity that best supplies a specific volume of water. Consequently, the expansion path of optimum solutions for different volumetric reliability of water supply can be determined. Additionally, the method based on the marginal rate of substitution can be used for determining the rational volumetric reliability. The procedures developed herein constitute an effective tool for preliminarily estimating the most satisfactory storage capacity of any specific roof area and for determining the rational reliability of a corresponding water supply.  相似文献   
982.
This paper explains how the well-accepted concept of improved stakeholder participation during mineral policy development leads to a national mineral policy that accommodates the diverging views and interests that allows wide acceptance of decisions, enhancing the success of implementation and, ultimately, national benefits. This process is based on lessons learnt during the South African experience and has been successfully applied in the development of the Namibian and Malawian national minerals policies. An effective policy in the SADC will engineer the delicate balance between poverty reduction and an internationally competitive minerals sector. This balance enhances the possibility of long-term economic growth and development in the SADC region. The overriding advantage of this strategy is that it generates ‘home-grown’ policy instruments and implementation of mineral law with which stakeholders can identify. This process presents a new challenge to traditional policy formulation strategies in emerging economies and the bottom-up approach, linked to wide political support, allows the potential realisation of national objectives.  相似文献   
983.
城镇建设用地需求预测与配置研究   总被引:11,自引:0,他引:11  
针对我国现行城镇建设用地预测方法存在的问题,对城镇建设用地预测方法进行了探索性研究;通过构建科学的建设用地需求预测方法,为土地利用规划提供科学依据。在C—D生产函数的基础上,提出了土地、资本与产出GDP的要素关系模型、恩格尔系数与人均建设用地面积关系模型和时间序列的ARIMA建设用地模型。对成都市城镇建设用地总量进行了实证分析,对4种预测方法的结果进行了定量评价,并据此提出成都市建设用地的配置方案。  相似文献   
984.
杨健  王浩  陆雍森 《四川环境》2003,22(5):22-24
运用生命周期分析(LCA)可对不同的废水处理工艺方案进行选择和比较,优选出资源消耗和环境污染最少的实施方案。其技术关键在于如何将ISO 14040等国际标准中规定的LCA方法学正确地应用至各种废水处理工艺的相对比较。本文对LCA应用于废水处理技术的一些基本概念进行了定义和探讨,其中包括废水处理系统的定义;废水处理厂的生命周期;废水处理工艺的功能、功能单位和基本流等。  相似文献   
985.
微生物法处理电镀废水技术概况与展望   总被引:5,自引:0,他引:5  
微生物法处理电镀废水技术倍受关注,文章在介绍国内外微生物法处理电镀废水的试验研究和大规模工业生产的基础上,总结了微生物法处理电镀废水的机理、工艺流程,优点及存在问题,并指出了这一技术的研究热点和发展前景。  相似文献   
986.
Mining with communities   总被引:2,自引:0,他引:2  
To be considered as sustainable, a mining community needs to adhere to the principles of ecological sustainability, economic vitality and social equity. These principles apply over a long time span, covering both the life of the mine and post-mining closure. The legacy left by a mine to the community after its closure is emerging as a significant aspect of its planning. Progress towards sustainability is made when value is added to a community with respect to these principles by the mining operation during its life cycle. This article presents a series of cases to demonstrate the diverse potential challenges to achieving a sustainable mining community. These case studies of both new and old mining communities are drawn mainly from Canada and from locations abroad where Canadian companies are now building mines. The article concludes by considering various approaches that can foster sustainable mining communities and the role of community consultation and capacity building.  相似文献   
987.
Shanghai is a cosmopolitan city and one of the most important economic centers in China, but is saddled with serious environmental problems resulting from a recent industrial transformation. This paper examines the interactive relationships between economic growth, eco-efficiency of urban metabolism, and environmental performance of the Shanghai metropolitan area since the 1990s using 15 indicators. This study has revealed an enhanced eco-efficiency of water and energy use as well as an improved overall environmental quality in the central urban districts of Shanghai. Both TGDP (total GDP) and GDP per capita increased rapidly at the annual rate of 16.28% and 15.91%, respectively. In contrast, energy consumed per 10000RMB YUAN GDP (ECG), water consumed per 10000RMB YUAN GDP (WCG), wastewater discharged per 10000RMB YUAN GDP (WWDG), and waste gases emitted per 10000RMB YUAN GDP (WGEG) decreased at the annual rate of 9.34%, 10.69%, 14.57%, and 8.52%, respectively. The rapid decline in ECG, WCG, WWDG, and WGEG indicates an enhanced eco-efficiency of urban metabolism. However, uncontrolled emission of wastes from domestic instead of industrial sources adversely affected the overall environmental quality. In addition, suburban areas have undergone rapid economic growth at the cost of human health deterioration, as measured by mortalities and relative mortality ratios of three major diseases (tumor, respiratory disease, and trauma/toxicosis). With Shanghai serving as the "locomotive" driving the economy of the Yangtze River Basin, effective pollution control policies and a network of regional coordination are urgently needed in the globalization and ecological security of the entire area.  相似文献   
988.
在抚宁县城城市空间形态研究中,通过对功能分区的划分、公共开敞空间的确定、道路景观轴线及视线通廊的控制、城市整体高度的组织,打造和谐共生的城市组团、营造充满魅力的公园、活力的社区邻里和文化内涵丰富的街区,旨在激发城市的活力,创造一个以自然生态环境为特色,以休闲度假、商务会议和生活居住为主体、充满活力的和谐城市。  相似文献   
989.
安徽省沿江地区生态功能分区研究   总被引:1,自引:0,他引:1  
在"中部崛起"战略和安徽省"沿江开发"战略的指引下,安徽沿江地区得以快速发展。合理划定区域生态功能区,确保经济发展与环境保护相协调具有重要现实意义。以GIS技术为支撑,从自然生态约束分区评价着手,以安徽沿江41个县市为基本单元,选择山地、水网、湿地、水环境容量等指标进行生态功能差异评价,经聚类归并以及兼顾功能区的完整连片,将安徽沿江地区划分为4个一级生态功能区1、4个二级生态功能区。安徽沿江地区生态功能分区对科学有效地管理安徽沿江生态环境,因地制宜地实施保护和治理策略,保证社会经济可持续发展,合理开发安徽沿江地区提供了研究支撑。  相似文献   
990.
Objective judgments, external to the judge, are compared with subjective, internal judgments. This analysis is made in the context of reaching regulatory decisions affecting the human environment. Examples given include evaluating the potential risk of industrial chemicals and comparing the potential effects of short- and long-term changes in land use. The analysis deals not with the decisions themselves, but rather with the kinds of questions that must be posed in orderto reach such decisions. Decision makers may spuriously distinguish objective from subjective types of judgment, though these are rarely wholly separate. Judges can hardly dispute about objective statements, if truly identical definitions are used. But subjective statements can reasonably be voted upon. Scientists, engineers, and economists represent logical or objective decision makers, tending to work in groups. Subjective thinkers include artists and performers, and others who often work alone. Moral and aesthetic aspects of questions, usually seen as intangible, are treated as if subjective. Financial decisions, usually viewed as tangible, are handled as objective problems. This mechanism for making decisions is well-established in environmental assessment. Though objective questions can be treated well in the monetary terms of cost-benefit analysis, subjective ones cannot. Mathematical and other variants are discussed in relation to the comparison of alternative types of tests.  相似文献   
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