全文获取类型
收费全文 | 5866篇 |
免费 | 431篇 |
国内免费 | 2059篇 |
专业分类
安全科学 | 576篇 |
废物处理 | 243篇 |
环保管理 | 459篇 |
综合类 | 3887篇 |
基础理论 | 951篇 |
污染及防治 | 1375篇 |
评价与监测 | 342篇 |
社会与环境 | 312篇 |
灾害及防治 | 211篇 |
出版年
2024年 | 35篇 |
2023年 | 101篇 |
2022年 | 321篇 |
2021年 | 298篇 |
2020年 | 309篇 |
2019年 | 215篇 |
2018年 | 247篇 |
2017年 | 294篇 |
2016年 | 256篇 |
2015年 | 331篇 |
2014年 | 428篇 |
2013年 | 571篇 |
2012年 | 519篇 |
2011年 | 555篇 |
2010年 | 446篇 |
2009年 | 419篇 |
2008年 | 403篇 |
2007年 | 406篇 |
2006年 | 325篇 |
2005年 | 249篇 |
2004年 | 184篇 |
2003年 | 209篇 |
2002年 | 170篇 |
2001年 | 152篇 |
2000年 | 156篇 |
1999年 | 111篇 |
1998年 | 92篇 |
1997年 | 100篇 |
1996年 | 109篇 |
1995年 | 80篇 |
1994年 | 74篇 |
1993年 | 59篇 |
1992年 | 49篇 |
1991年 | 16篇 |
1990年 | 24篇 |
1989年 | 14篇 |
1988年 | 3篇 |
1987年 | 7篇 |
1986年 | 5篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有8356条查询结果,搜索用时 15 毫秒
181.
BaO/γ-Al2O3同时吸附脱除一氧化氮和二氧化硫 总被引:1,自引:0,他引:1
利用固定床连续流动反应器研究了BaO/γ—Al2O,同时吸附模拟烟气中NO和SO2的工艺条件和再生循环使用性能,对BaO/γ—Al2O3进行了比表面积和程序升温表面反应(TPSR)等表征分析。结果表明,BaO/γ—Al2O3的适宜工艺条件是SO2与NO体积比为2.9~8.4、原料气中O2体积分数大于4.5%、吸附温度448~523K。BaO/γ—Al2O3在循环使用过程中吸附能力下降。与NOXSO吸附催化剂Na2CO3/γ—Al2O3相比,BaO/γ-Al2O3同时吸附SO2和NO的能力大、再生循环使用性能好、适宜的SO2与NO体积比范围宽、热稳定性好。将BaO/γ—Al2O3应用于NOXSO工艺可望提高该工艺的脱硫、脱氮效率。 相似文献
182.
美国环保超级基金制度及其实施 总被引:2,自引:0,他引:2
对美国环保超级基金制度的概念和内容作了简要的介绍,并指出了其实施过程中的成功与不足,以期为我国环境法制的完善提供有益的借鉴。 相似文献
183.
184.
论高职高专英语教学改革——我院英语分级教学探索 总被引:1,自引:0,他引:1
根据目前我院英语教学状况,英语公共课有必要改革"单一目标"的教学模式,采用多目标个性化分层教学模式,提高学生英语素质.文中具体探讨了多目标个性化分级教学模式的内涵、实施的前提条件、依据及策略. 相似文献
185.
186.
Xu Li Zimeng Liu Qing Xu Zhongyi Jiang Guoliang Ma 《Environmental Modeling and Assessment》2017,22(3):243-255
In this paper, we construct a multi-stage coordinated programming model under tax system to control SO2 emission. The model is based on an explicitly formulated SO2 abatement cost function created under Chinese condition. Analysis of the effectiveness and impact on the economy of the model is carried out with consideration of game theory. By solving the model, theoretical results show that the volume-based multi-stage SO2 tax system has two properties: effectiveness and equal-rate. Based on these theoretical results, empirical study is also performed using Chinese historical data. Compared with yearly single-stage programming model, the tax rate generated by the coordinated multi-stage programming model is time-invariant and rather moderate in scale. The total abatement cost among planning years in our model is 21.03 % less than the actual number and 6.68 % less than that in the single-stage situation. The tax payment suggested by our model is 10.62 % less than by the single-stage model. In general, a coordinated multi-stage programming model helps reduce the overall costs of environmental protection while achieving the same emission control target with less burden added to the economy. 相似文献
187.
Chen Yujun Guan Bin Wu Xingze Guo Jiangfeng Ma Zeren Zhang Jinhe Jiang Xing Bao Shibo Cao Yiyan Yin Chengdong Ai Di Chen Yuxuan Lin He Huang Zhen 《Environmental science and pollution research international》2023,30(5):11246-11271
Environmental Science and Pollution Research - In recent years, with global climate change, the utilization of carbon dioxide as a resource has become an important goal of human society to achieve... 相似文献
188.
为分析共因失效对高速铁路接触网系统的影响,将二元决策图(Binary Decision Diagram,BDD)与共因失效理论引入到接触网系统可靠性分析中。利用逻辑相邻优先组合法(Logic Neighbor Priority Connect,LNPC)将高速铁路接触网系统的故障树模型转化为BDD模型并求取其可靠度表达式,利用隐式方法对考虑了共因失效的接触网系统可靠度进行计算,利用MATLAB绘制考虑共因失效和不考虑共因失效情况下接触网系统可靠度变化曲线。研究结果表明:提出的分析方法适用于接触网系统的可靠性分析,为接触网系统的可靠性分析提供了一定的理论依据。 相似文献
189.
Lingling Wu Yue Jiang Lili Zhang Ling Chen Haiping Zhang 《Environmental science and pollution research international》2014,21(4):2663-2676
Pollution from urban highway runoff has been identified as one of the major causes of the deterioration of receiving water quality. The purpose of this study is to assess the toxicity of urban storm water samples in Shanghai using the zebrafish (Danio rerio) embryo test and the bacterial luminescence (Vibrio qinghaiensis) assay. The toxicity of highway runoff from seventeen storm events was investigated in both grab and composite samples. Zebrafish embryos were exposed to the runoff samples and development parameters including lethality, spontaneous movements in 20 s, heart beat rate, hatching rate, and abnormality of zebrafish embryos were observed after 24, 48, 72, and 96 h of exposure. Inhibition rates of luminescence intensity were also recorded. The results showed that in the zebrafish embryo toxicity tests, both grab and composite samples increased the lethality, reduced the percentage with spontaneous movements and heart beats, inhibited the hatching of embryos, and induced morphological abnormalities. In the Vibrio qinghaiensis toxicity test, all the grab samples inhibited the luminescence, while some of the composite samples promoted it, which indicated that different types of toxicants might have been affecting the species. The multivariate statistics analysis indicated that heavy metal (zinc, manganese, and copper) and PAHs might mainly contribute to the toxicity of runoff samples. 相似文献
190.
Li Jintao Jiang Changjun Xing Zhanjun 《Environment, Development and Sustainability》2021,23(8):12151-12168
Environment, Development and Sustainability - With the rapid development of industrialization and urbanization and the continuous improvement of social productivity, people are increasingly... 相似文献