全文获取类型
收费全文 | 4386篇 |
免费 | 241篇 |
国内免费 | 264篇 |
专业分类
安全科学 | 389篇 |
废物处理 | 231篇 |
环保管理 | 1391篇 |
综合类 | 1748篇 |
基础理论 | 235篇 |
环境理论 | 5篇 |
污染及防治 | 121篇 |
评价与监测 | 120篇 |
社会与环境 | 573篇 |
灾害及防治 | 78篇 |
出版年
2024年 | 10篇 |
2023年 | 39篇 |
2022年 | 75篇 |
2021年 | 99篇 |
2020年 | 116篇 |
2019年 | 103篇 |
2018年 | 94篇 |
2017年 | 144篇 |
2016年 | 169篇 |
2015年 | 150篇 |
2014年 | 178篇 |
2013年 | 218篇 |
2012年 | 259篇 |
2011年 | 284篇 |
2010年 | 229篇 |
2009年 | 178篇 |
2008年 | 167篇 |
2007年 | 240篇 |
2006年 | 202篇 |
2005年 | 213篇 |
2004年 | 192篇 |
2003年 | 195篇 |
2002年 | 145篇 |
2001年 | 113篇 |
2000年 | 147篇 |
1999年 | 166篇 |
1998年 | 94篇 |
1997年 | 81篇 |
1996年 | 60篇 |
1995年 | 77篇 |
1994年 | 56篇 |
1993年 | 59篇 |
1992年 | 52篇 |
1991年 | 38篇 |
1990年 | 25篇 |
1989年 | 11篇 |
1988年 | 14篇 |
1986年 | 10篇 |
1985年 | 12篇 |
1984年 | 11篇 |
1983年 | 14篇 |
1981年 | 11篇 |
1980年 | 13篇 |
1979年 | 16篇 |
1978年 | 12篇 |
1977年 | 13篇 |
1975年 | 9篇 |
1973年 | 14篇 |
1972年 | 10篇 |
1971年 | 18篇 |
排序方式: 共有4891条查询结果,搜索用时 0 毫秒
991.
Project appraisal and planning for overdeveloped countries: I. The costing of nonrenewable resources
Colin Price 《Environmental management》1984,8(3):221-232
In cost-benefit analysis, natural resources, like other factors of production, should be costed as a mixture of marginal social cost of exploiting additional resources and lost marginal social benefit of forgone alternative uses, according to the way in which extra resources are made available to a project. For a nonrenewable resource, changes in future marginal social cost and marginal social benefit are likely to add significantly to the immediate elements of cost, as successively less tractable resource stocks are exploited. Of the several reasons given for ignoring these future costs, the most plausible is that technological advance justifies a heavy discount on the future. However, neither historical nor logical arguments demonstrate the inevitability of efficacious technological advance. 相似文献
992.
刘虹 《中国人口.资源与环境》1996,6(2):31-35
江苏省南部地区是我国经济相对发达的区域,其基本特点是人口较多、资源利用程度相对充分、环境压力相对较大,在发展中需要转变经济增长方式,合理利用资源和保护环境.实现可持续发展。 相似文献
993.
ABSTRACT: The SMEMAX transformation, its modified versions and power transformation were applied to 55 long-term records of annual maximum flood flows tested previously for independence, homogeneity and completeness. Even though SMEMAX transformation reduced the coefficient of skewness to near zero for flood data, their distribution was not a true normal distribution. In almost all cases, the coefficient of kurtosis was quite different from 3.0 of the normal distribution. Empirical criteria showed that SMEMAX transformation performed well only for 40 (70 percent) of the 55 stations tested. Its performance level dropped, especially for stations which had both the coefficient of skewness and kurtosis greater than 3.0 and 10.0, respectively. Power transformation was generally better in transforming the flood data to a normal distribution. It performed well for 50 (90 percent) of the 55 stations tested. The coefficient of skewness in case of the data transformed by power transformation was much closer to the zero value than in the case of SMEMAX transformed series. The SMEMAX transformation and its two modified versions yielded identical results when flood frequency analysis was performed. Computationally, all three methods were equally simple and easy to apply for flood frequency analysis. In some cases, the coefficient of kurtosis for the transformed distributions obtained both by SMEMAX and power transformations deviated farther from that for the normal distribution than for the parent distribution. 相似文献
994.
Ambrose Goicoechea Eugene Z. Stakhiv Fu Li 《Journal of the American Water Resources Association》1992,28(1):89-102
ABSTRACT: A research project was undertaken for the U.S. Army Corps of Engineers to determine the relative utility and effectiveness of four well-known multicriteria decision making (MCDM) models for applications in realistic water resources planning settings. A series of experiments was devised to examine the impact of rating and ranking procedures on the decision making behavior of users (e.g., planners, managers, analysts, etc.) when faced with situations involving multiple evaluation criteria and numerous alternative planning projects. The four MCDM models tested were MATS-PC, EXPERT CHOICE, ARIADNE, and ELECTRE. Two groups of analysts and decision makers were tested. One group consisted of experienced U.S. Army Corps planners, while the other was comprised of graduate students. Based on a series of nonparametric statistical tests, the results identified EXPERT CHOICE as the preferred MCDM model by both groups based largely on ease of use and understandability. ARIADNE fostered the largest degree of agreement within and among the two groups of individuals tested. The tests also lend support to the claim that rankings are not affected significantly by the choice of decision maker (i.e., who uses any of these MCDM models) or which of these four models is used. 相似文献
995.
996.
火电厂废水的净化与回收利用 总被引:3,自引:0,他引:3
李贤贵 《石油化工环境保护》2001,(4)
针对火电厂废水悬浮物含量高、粒径小、难分离、废水量大的特点 ,采用高浊度废水净化技术 ,优化工艺流程 ,实现了火电厂所有废水的净化与回收利用 ,且经济效益显著。 相似文献
997.
长春市污水资源化现状及对策 总被引:2,自引:0,他引:2
论述了长春市水资源现状,并提出水资源可持续利用的途径——污水资源化,加快长春市生态省建设的步伐,促进可持续发展战略的顺利实施。 相似文献
998.
999.
我国城市垃圾综合治理现状及其发展方向 总被引:1,自引:0,他引:1
穆莹 《资源节约和综合利用》2000,(1):28-29,14
本文在分析我国城市垃圾治理现状的同时,从清洁生产、资源化角度探讨其发展前景,阐述了垃圾综合整治的若干对策。 相似文献
1000.
本文深入探讨了高校主体性人力资源的特点及其职业生涯发展的主要特征,针对高校当前在职业生涯发展管理上存在的主要问题,提出了进行管理创新的几个基础性工作,为全面有效地进行职业生涯发展管理奠定坚实的基础. 相似文献