全文获取类型
收费全文 | 968篇 |
免费 | 38篇 |
国内免费 | 332篇 |
专业分类
安全科学 | 52篇 |
废物处理 | 67篇 |
环保管理 | 99篇 |
综合类 | 494篇 |
基础理论 | 145篇 |
污染及防治 | 346篇 |
评价与监测 | 49篇 |
社会与环境 | 50篇 |
灾害及防治 | 36篇 |
出版年
2023年 | 19篇 |
2022年 | 45篇 |
2021年 | 36篇 |
2020年 | 30篇 |
2019年 | 33篇 |
2018年 | 45篇 |
2017年 | 47篇 |
2016年 | 49篇 |
2015年 | 43篇 |
2014年 | 57篇 |
2013年 | 96篇 |
2012年 | 67篇 |
2011年 | 90篇 |
2010年 | 68篇 |
2009年 | 56篇 |
2008年 | 56篇 |
2007年 | 63篇 |
2006年 | 48篇 |
2005年 | 46篇 |
2004年 | 29篇 |
2003年 | 32篇 |
2002年 | 31篇 |
2001年 | 21篇 |
2000年 | 38篇 |
1999年 | 25篇 |
1998年 | 27篇 |
1997年 | 26篇 |
1996年 | 25篇 |
1995年 | 13篇 |
1994年 | 15篇 |
1993年 | 6篇 |
1992年 | 12篇 |
1991年 | 11篇 |
1990年 | 15篇 |
1989年 | 4篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有1338条查询结果,搜索用时 563 毫秒
601.
微生物絮凝剂产生菌的絮凝性能 总被引:7,自引:0,他引:7
从废水处理厂和土壤中分离产絮凝剂的菌株,其中一株产絮凝剂的细菌W7—1对高岭土的絮凝活性达94%,初步鉴定该菌为Klebiella sp.,W7—1对产絮凝剂的培养条件要求简单,产絮凝剂的最佳碳源和氮源为蔗糖和牛肉膏,pH在5~10的范围内都适应絮凝剂的产生,但pH为8.0时絮凝活性最高。絮凝剂的添加量为10mL/L、絮凝体系pH为7~10时絮凝活性好,提纯后的絮凝剂产量高于其它絮凝剂近10倍,分析表明,絮凝剂成分为多糖,且有很好的热稳定性,加热至100℃、30min后絮凝活性不变。 相似文献
602.
603.
604.
Xing-Ming Hao Yang Li Hai-Jun Deng 《Environmental monitoring and assessment》2013,185(12):10027-10038
The roots of Populus euphratica, a plant that grows in the lower reaches of the Tarim River, Northwest China, exhibit a significant level of hydraulic redistribution; however, quantitative assessments of the water-sharing process and its ecological effects are limited. This study was designed to obtain such data using an assessment model based on field observation parameters, including soil water content (soil water potential), root distribution, and stable isotope δ18O values of soil and plant samples during the entire growing season. The results showed that hydraulic redistribution in P. euphratica can be detected in 0–120 cm soil layers, with the amount of hydraulically redistributed water (HRW) in the soil found at different depths as follows: 60–80?>?40–60?>?20–40?>?0–20?>?80–100?>?100–120 cm. The variations in HRW in soil layers can be partly attributed to the vertical distribution of roots. The denser roots found at greater depths positively influenced the amount of redistributed water in lower soil layers. During the growing season, the amount of HRW reached a daily average of 0.27 mm, which allowed increased transpiration and provided an adequate water supply to herbs. Based on the stable isotope (δ18O) data, the amount of HRW provided by the roots of P. euphratica could meet 22–41 % of its water demand. 相似文献
605.
Tao Hu-Chun Li Shuo Zhang Li-Juan Chen Yi-Zhen Deng Li-Ping 《Environmental geochemistry and health》2019,41(1):297-308
Environmental Geochemistry and Health - Using sodium alginate hydrogel as skeleton, in combination with chitosan and magnetic Fe3O4, a new type of magnetic chitosan/sodium alginate gel bead (MCSB)... 相似文献
606.
Qinghe Zhao Shiliang Liu Li Deng Shikui Dong Cong Wang 《Environmental monitoring and assessment》2013,185(7):6101-6110
In this study, the longitudinal distribution of heavy metals (including As, Cd, Cr, Cu, Ni, Pb, and Zn) from sediment of a 70-km long canyon reservoir in Yunnan Province was investigated and their potential ecological risks were assessed. The results indicated that the concentration of all the detected metals in the sediments that was sampled near the dam was much higher than that sampled from upstream far from the dam. The geoaccumulation index (I geo) and contamination factors (CF) suggested that Cd was the most important contamination factor, followed by As and Zn, while the concentration of Cr, Cu, Ni, and Pb was at uncontaminated levels. Cd posed a high potential ecological risk in the sediment. Furthermore, potential ecological risk is significantly correlated with the distance from the dam. 相似文献
607.
Deng Nan 《中国人口.资源与环境(英文版)》2013,11(1):3-6
Abstract Population, resources and environment constitute the basis for economic and social advances. Their coordinative development is the key factor for the continuous, stable and harmonious development of economy and society. China is a developing country which needs to mobilize the whole society to coordinate among population, resources and environment and to keep publicity and research in pace so as to deepen people's understanding and improve the methods of achieving this coordination. 相似文献
608.
Abstract Population, resources, environment and socio-economic development are four major issues of increasing world attention today and are also four major factors constraining China's development tomorrow. Through an analysis of the international situation and an assessment of China's actual conditions, this article proposes a basic framework and conception of promoting the sustainability of China's population, resources, environment and socio-economic development. 相似文献
609.
610.
Geng Mingming Niu Yandong Liao Xiaohong Wang Kelin Yang Nan Qian Zhan Li Feng Zou Yeai Chen Xinsheng Deng Zhengmiao Xie Yonghong 《Environmental science and pollution research international》2022,29(10):14083-14097
Environmental Science and Pollution Research - The hydrological conditions of river-connected lakes are complex primarily owing to their considerable water-level fluctuations (WLFs). Water quality... 相似文献