首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   662篇
  免费   35篇
  国内免费   247篇
安全科学   50篇
废物处理   55篇
环保管理   44篇
综合类   348篇
基础理论   136篇
污染及防治   228篇
评价与监测   29篇
社会与环境   25篇
灾害及防治   29篇
  2023年   12篇
  2022年   38篇
  2021年   34篇
  2020年   22篇
  2019年   23篇
  2018年   25篇
  2017年   29篇
  2016年   27篇
  2015年   49篇
  2014年   53篇
  2013年   73篇
  2012年   47篇
  2011年   59篇
  2010年   43篇
  2009年   29篇
  2008年   35篇
  2007年   50篇
  2006年   33篇
  2005年   24篇
  2004年   18篇
  2003年   23篇
  2002年   19篇
  2001年   17篇
  2000年   22篇
  1999年   31篇
  1998年   17篇
  1997年   16篇
  1996年   15篇
  1995年   9篇
  1994年   9篇
  1993年   9篇
  1992年   10篇
  1991年   7篇
  1990年   7篇
  1989年   3篇
  1988年   1篇
  1987年   1篇
  1986年   2篇
  1982年   2篇
  1981年   1篇
排序方式: 共有944条查询结果,搜索用时 250 毫秒
491.
用Ultra-2320μm柱分离2,4-滴,2,4-二氯酚及2,4,6-三氯酚。保证了检测结果有足够的精确度。用直接进水样技术而不必处理水样,使检测结果更趋精确。  相似文献   
492.
为深入了解邢台市PM_(10)、PM_(2.5)浓度变化情况和气流后向轨迹,对邢台市2013—2016年环境大气颗粒污染物监测数据进行了分析,同时利用HYSPLIT模型计算出逐日72 h后向气流轨迹。结果表明:邢台市的PM_(10)和PM_(2.5)质量浓度在2013—2016年间呈逐年下降趋势,PM_(10)和PM_(2.5)质量浓度高值出现在冬季(296μg/m~3和192μg/m~3),最低值出现在夏季(140μg/m~3和80μg/m~3),PM_(10)和PM_(2.5)质量浓度在日变化上均呈"双峰双谷"型分布;后向轨迹的季节聚类分析表明,春季大气颗粒物污染以粒径2.5~10μm的颗粒污染物为主,夏季、秋季和冬季的大气颗粒物污染以PM_(2.5)为主;逐日聚类分析表明,在路径为西北偏西向的、途经多个沙源地的气流影响下,邢台市的PM_(10)和PM_(2.5)质量浓度处于一个相对高值;来源于偏南向的气流由于化合反应,污染物积聚导致PM_(10)、PM_(2.5)质量浓度也处于相对高值;在来源于西北向和偏北向的、水汽含量相对较低的气流影响下,邢台市的PM_(10)、PM_(2.5)质量浓度出现一个明显的下降。  相似文献   
493.
Autism spectrum disorders are a member of the pervasive developmental disorders (PDDs) that have been increasing dramatically since described by Leo Kanner in 1943. In the past decade, the number of epidemiological publications addressing air pollution exposures and autism has grown correspondingly, but the association is still unclear. Whether air pollutants play a causal role and which substances are related with autism requires further study. We systematically reviewed the literature from 2005 to 2016 in MEDLINE (National Library of Medicine), Web of Science, and PubMed and summarized the association between different air pollutants and autism. Furthermore, we further discussed the exposure time window and potential confounders that should be considered in the association analysis studies. Our objective is to summarize the association between different air pollutants and autism with literature, which has been published since 2005, and explore whether the exposure time window and potential confounders have influence on this association. These results could provide more comprehensive information about the association between air pollutants and autism and be helpful towards further validation study.
Graphical abstract ?
  相似文献   
494.
总结了国内外化学修复法和生物修复法修复火炸药生产废水污染土壤的研究进展。比较了各种方法的优缺点,提出了未来火炸药生产废水污染土壤修复技术的研究方向。指出:应将物理修复法、化学修复法及生物修复法相结合,将修复定位于综合化、彻底化及可利用化,以期达到火炸药生产废水污染土壤的无害化治理。  相似文献   
495.
It is well-known that Poria vaporaria (Pers.:Fr.) Cooke, Paecilomyces variotii Bainier and Aspergillus niger are fungi and molds which destroy bamboo. The aim of this study was to compare the effectiveness of antibacterial activity of 16 flavonoids in preventing the actions of these three bamboo-destroying fungi and molds (Poria vaporaria (Pers.:Fr.) Cooke, Paecilomyces variotii Bainier and Aspergillus niger). The results showed that baicalein(1) exerted the highest inhibitory effect on Poria vaporaria (Pers.:Fr.) Cooke and Paecilomyces variotii Bainier indicating that baicalein(1) may be considered as a potential agent to develop as natural bactericide to preserve natural bamboo.  相似文献   
496.
Environmental indicator systems are a fundamental tool in quantifying the environmental component of sustainable development. They are useful because they quantify the status and trends of key environmental parameters and provide information on the environment that allows authorities and communities to make informed decisions. This article analyzes the basic framework for Chinese environmental indicator systems and presents a “core” set of environmental indicators. In our research, we used a theme approach to develop the environmental indicator systems. We performed two case studies of selected indicators. In the first, we used an urban ambient air pollution composite index and an urban ambient air pollution indicator for three main pollutants to examine trends in urban air pollution in China from 1990 to 2000 at regional and national levels. The results indicate that China has made some progress towards controlling urban air pollution, but must do more in order to reach acceptable pollution levels. We think that an aggregated index and disaggregated indicators have important complementary roles in the policy-making processes. In the second case study, we developed and constructed a grassland degradation index that aggregates information on the extent and severity of grassland degradation. Taking the Xilinhaote region of Inner Mongolia as the study area, we calculated this index by combining remote-sensing data, a geographical information system (GIS), and field investigation. Based on these results, we provide recommendations regarding further development and measurement of environmental indicators in China.  相似文献   
497.
利用185~253.7 nm紫外光联合降解低浓度二硫化碳废气.结果表明,在一定的气体浓度、流速以及湿度下,该技术能够有效降解二硫化碳使其浓度低于人的嗅阈值,同时研究也发现,该技术对苯乙烯和甲苯二甲苯等有机废气也有同样的处理效果,具有很好的工业化应用前景.  相似文献   
498.
Along with their rapid progress, developing countries have had to deal with more environmental problems, which have been a cause for concern among policy makers and the public in general. This study cites two accidents that happened in China in 2006 that caused serious environmental problems in nearby communities and discusses the problems these accidents created and the resulting disputes among the concerned people. Pollution-causing accidents not only pose threats to the health of the victims but also give rise to environmental disputes that jeopardise national security and social stability. Conflicts normally ensue following a pollution-causing accident, which are more likely to happen within a development zone or industrial park. Few environmental conflicts in the past decades were resolved through litigation. Nevertheless, there are lapses in the regulatory system, which have to be addressed to ensure that the public's rights and interests are protected. Currently, reports on pollution-causing accidents are difficult to obtain and are often released very late. A majority of industrial firms operate without environmental clearance, thus highlighting the government's inefficiency in environmental management. It is about time that the Chinese government takes seriously the use of the Environmental Impact Assessment.  相似文献   
499.
针对水中微量铅离子和氯乙酸的脱除,考察了成型膨润土及成型钛柱撑膨润土的吸附性能,得出对铅离子的吸附,成型膨润土、成型钛柱撑膨润土与粉末状活性炭性能相当,而对氯乙酸的吸附前两者要比粉末状活性炭低好多.确定了成型膨润土吸附氯乙酸后可用沸水煮沸30 min的方法再生,成型钛柱撑膨润土吸附氯乙酸后,可用500℃焙烧3 h的方法再生,再生的膨润土循环使用3次后性能降低明显.此外,还测得了成型的膨润土及成型的钛柱撑膨润土吸附铅离子和氯乙酸的等温线,计算出其对铅的最大吸附量分别为24.33 mg/g和15.47 mg/g.  相似文献   
500.
钛基修饰氧化物电极制备及降解苯胺的研究   总被引:2,自引:1,他引:1  
采用高温热氧化法制备了钛基锡锑铅氧化物电极,得到的电极具有较高的电催化活性和良好的稳定性,并以苯胺为目标有机物考察了电压、电解质的浓度、pH值和电解时间等因素对苯胺去除率和化学需氧量COD等的影响.在外加电压为8 V,电解质硫酸钠的浓度为0.15 mol/L,电解200 mg/L的苯胺模拟废水,40 min苯胺去除率可达100%,180 min时COD去除率达81.76%.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号