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261.
The primary task for the environmental state is to address problems related to the market’s externalisation of environmental costs. It has four main resources at its disposal: regulation, redistribution, organisation, and knowledge generation. The way these four resources are deployed make up a state’s environmental governance arrangements. Using data on environmental regulation, taxes, public administrations, and knowledge production from 28 countries, and a hierarchical cluster analysis, four different types of environmental states are identified: established, emerging, partial, and weak. This is followed by some suggestions for further research on the environmental state in a comparative perspective.  相似文献   
262.
Australia and Sweden display very different institutional settings and contexts for the production of environmental journalism. This empirical study examined how two major quality newspapers in Sweden and Australia have framed renewable energy as an environmental, political, scientific, economic and civil society issue. A deductive, quantitative methodological approach was used to identify dominant frames and actors in articles in The Australian (Australia) and Dagens Nyheter (Sweden) between October 2010 and June 2011 2010/2011. The findings suggest that the attention given to different types of renewable energy in the two newspapers and how issues were framed was contingent on the domestication of the discussion of renewable energy in the two countries. Reporting on renewable energy in both newspapers was characterized by a focus on “elite” actors and economic frames, the absence of civil society frames and negative (The Australian) or ambiguous (Dagens Nyheter) environmental frames. The study extends our understanding of the contextual conditions that enable and limit journalists when reporting environmental issues.  相似文献   
263.
Jan Karlas 《环境政策》2017,26(5):825-846
Why do some states and state coalitions, acting within the United Nations Framework Convention on Climate Change (UNFCCC), support harder legalization of the global climate regime? In order to explain why, the effects of four causal factors are considered: climate vulnerability, the emission intensity of the national economy, a state’s power position, and socialization into climate norms. To identify the legalization positions of UNFCCC actors, an original content analysis is conducted of all the submission and meeting statements made at the Ad Hoc Working Group on the Durban Platform during the years 2012–2015. Subsequently, a qualitative comparative analysis is carried out to find out which combinations of the causal factors offer a sufficient explanation for the analyzed outcome, leading to the identification of two causal pathways that lead states to endorse harder legalization of the climate regime.  相似文献   
264.
依据田间实测资料,运用水流的电模拟原理,定且分析了南亚热带丘陵赤红壤-果树(荔枝、芒果和龙眼)-大气连续体中水流阻力各分量的大小、变化规律及其相对重要性.结果表明,连续体中的水流阻力主要分布于从叶气孔腔到大气的扩散过程,荔枝、芒果、龙眼叶-气系统的水流阻力Rla占连续体水流总阻力Rsa的比例分别为93.65%~98.03、95.68%~99.03%、90.13%~98.71%;果树植株体的水流阻力Rp居其次,占Rsa的比例分别为1.97%~6.35%、0.97%~4.32%、0.08%~9.87%:土壤阻力Rs最小,占Rsa的比例小到可忽略不计,故叶-气系统的水流阻力是决定连缤体中水流速率的重要因素.  相似文献   
265.
根据数理统计的原理,将环境质量标准,平均值,标准偏差以及样本容量综合进行考虑,提出了污染分界线的计算公式,并以表格形式给出了不同显著性水平下,不同的相对标准偏差和样本容量所对应的污染分界线,对污染分界线与样本容量及相对标准的偏差的关系进行了讨论,指出提高监测精度和适当增加监测数据个数,可以使污染分界线接近评价标准。  相似文献   
266.
我国开发区土地资源配置效率的区域差异研究   总被引:11,自引:0,他引:11  
应用比较优势理论,以国家级53个经济技术开发区为例。研究了不同区域间开发区土地利用的比较优势。结果表明。按照区域土地利用的比较优势来配置土地资源能够提高土地利用的总福利水平。整体上.中西部国家级开发区的比较优势高于东部地区:而区域内部东部地区的京津苏沪及中西部地区的中心城市在开发区建设用地的利用上具有比较优势。因此,按照开发区土地利用的比较优势度计算结果,在排除开发区自身发育不完善和管理层面因素后,对于确实不适宜进行开发区工业建设的应进行空间布局的调整,恢复其农业生产;而对于比较优势度较高的地区可根据实际需要增设相应的开发区。以实现耕地保护与开发区建设的双赢。  相似文献   
267.
人类活动对浙江近海赤潮发生频率的影响分析   总被引:1,自引:0,他引:1  
根据1933年到2004年间的统计资料,以10 a为周期分析了浙江沿岸赤潮的发展变化历程,并进一步以1997~2004年的统计资料为基础,采用灰色系统关联分析法研究了的浙江近海赤潮的发生频率和人类活动引起的营养物质输入的关系.结果表明,各相关因子对赤潮发生频率影响的关联序为:海水养殖产量(0.03)>海水养殖面积(0.99)>工业废水(0.89)>生活污水(0.88)>生活COD(0.79)>总悬浮颗粒物(0.75)>工业COD(0.72)>降雨量(0.71)>粉尘(0.69)>烟尘(0.68).可见,赤潮发生与人类活动关系密切,其中海洋养殖自身污染是赤潮发生频率的主要诱因,陆源污染和大气湿沉降起着重要作用.  相似文献   
268.
Dechlorination of carbon tetrachloride by the catalyzed Fe-Cu process   总被引:2,自引:0,他引:2  
The electrochemical reduction characteristics of carbon tetrachloride (CT) were investigated using cyclic voltammetry in this study. In addition, the difference in reduction mechanisms of CT between Master Builders' iron and the catalyzed Fe-Cu process was discussed. The results showed that CT was reduced directly on the surface of copper rather than by atomic hydrogen produced at the cathode in the catalyzed Fe-Cu process. The reduction was realized largely by atomic hydrogen in Master Builders' iron. The entire CT in 350 ml aqueous solution with 320 mgL was reduced to trichloromethane and dichloromethane in 2.25 h when 100 g of scrap iron with FeCu ratio of 10:1 (ww) were used. Moreover, the reduction rate slowed with time. CT could be reduced at acidic, neutral and alkaline pH from solution by Fe-Cu bimetallic media, but the mechanisms were di?erent. The degradation rate was not significantly in?uenced by pH in the catalyzed Fe-Cu process; in Master Builders' iron it clearly increased with decreasing pH. The kinetics of the reductions followed pseudo-first order in both cases. Furthermore, the reductions under acidic conditions proceeded faster than that under the neutral and alkaline conditions. The catalyzed Fe-Cu process was superior to Master Builders' iron in treating CT-containing water and this advantage was particularly noticeable under alkaline conditions. The reduction was investigated in the cathode (Cu) and anode (Fe) compartments respectively, the results showed that the direct reduction pathway played an important role in the reduction by the catalyzed Fe-Cu process. The catalyzed Fe-Cu process is of practical value.  相似文献   
269.
石首天鹅洲六合垸扩大麋鹿栖息地初析   总被引:1,自引:0,他引:1  
自石首麋鹿国家级自然保护区设立以来,麋鹿种群得到了有效发展。因各种因素综合作用,现有保护区已呈现容纳量不足的趋势。相较其它湿地,依据岛屿生物地理学“平衡理论,”与麋鹿保护区相连通的六合垸似乎在扩大麋鹿栖息地方面具有地理优势。文章侧重从景观学(形状、连接度、廊道构建)及社会(移民)两个角度对其优势度状况作尝试性分析,进而得出六合垸并不具有明显优势的初步结论。  相似文献   
270.
陈云生 《环境技术》2007,25(6):14-17
本文用四达公司生产的环境试验设备产品实测数据,讨论相对湿度风速修正与大气压力修正的必要性和计算方法.  相似文献   
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