全文获取类型
收费全文 | 678篇 |
免费 | 48篇 |
国内免费 | 153篇 |
专业分类
安全科学 | 33篇 |
废物处理 | 55篇 |
环保管理 | 77篇 |
综合类 | 372篇 |
基础理论 | 77篇 |
污染及防治 | 178篇 |
评价与监测 | 33篇 |
社会与环境 | 24篇 |
灾害及防治 | 30篇 |
出版年
2024年 | 1篇 |
2023年 | 9篇 |
2022年 | 35篇 |
2021年 | 29篇 |
2020年 | 18篇 |
2019年 | 17篇 |
2018年 | 20篇 |
2017年 | 25篇 |
2016年 | 24篇 |
2015年 | 32篇 |
2014年 | 52篇 |
2013年 | 56篇 |
2012年 | 56篇 |
2011年 | 56篇 |
2010年 | 52篇 |
2009年 | 45篇 |
2008年 | 39篇 |
2007年 | 38篇 |
2006年 | 26篇 |
2005年 | 27篇 |
2004年 | 17篇 |
2003年 | 23篇 |
2002年 | 25篇 |
2001年 | 24篇 |
2000年 | 22篇 |
1999年 | 20篇 |
1998年 | 16篇 |
1997年 | 21篇 |
1996年 | 7篇 |
1995年 | 8篇 |
1994年 | 7篇 |
1993年 | 6篇 |
1992年 | 5篇 |
1991年 | 6篇 |
1990年 | 1篇 |
1989年 | 4篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1978年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有879条查询结果,搜索用时 828 毫秒
401.
N原子杂化石墨烯高效活化过一硫酸盐降解RBk5染料废水 总被引:6,自引:4,他引:2
过硫酸盐高级氧化技术使用过程中,活化剂的大量流失与其环境二次危害是影响该技术应用的主要限制因素.针对这一问题本研究采用改进的Hummers法结合水热法制备环境友好型的N原子掺杂石墨烯作为催化剂,活化过一硫酸盐(PMS)产生硫酸根自由基(SO4-·)和羟基自由基(·OH)降解活性黑5(RBk5)染料.利用傅立叶红外光谱,X-射线光电子能谱,拉曼光谱和透射电子显微镜对N原子掺杂石墨烯进行表征.对催化剂催化性能进行研究,考察了初始p H、催化剂投加量和PMS投加量等因素对降解过程的影响.结果表明,N元素掺杂能够有效提升石墨烯材料的PMS催化活性,且活性受N掺杂比例影响较大;废水的初始p H对降解效率无明显影响.催化剂投加量为1. 5 g·L-1,PMS投加量为0. 3 g·L-1的条件下,反应25min后RBk5染料废水的降解率可达到99%以上,反应过程符合一级反应动力学.自由基猝灭实验显示,N掺杂石墨烯/PMS体系降解RBk5为表面反应,SO4-·和·OH为降解RBk5的主要自由基.循环实验证明催化剂稳定性能良好. 相似文献
402.
Environmental residues of aromatic ionizable organic compounds (AIOCs) have received considerable attention due to their potential human health and ecological risks. The main objective of this study was to investigate the key factors and mechanisms controlling sorption of a series of anionic and zwitterionic AIOCs (two aromatic sulfonates, 4-methyl-2,6-dinitrophenol, tetracycline, sulfamethoxazole, and tannic acid) to montmorillonites modified with hexadecyltrimethyl ammonium (HDTMA) and polydiallyldimethyl ammonium (PDADMA). Compared with naphthalene (a nonpolar and nonionic solute), all AIOCs showed stronger sorption (the sorbent-to-solution distribution coefficient was in the order of 10-10 L kg) to the two organoclays in spite of the much lower hydrophobicity, indicating the predominance of electrostatic interaction in sorption. The proposed electrostatic mechanism of the tested AIOCs was supported by the pH dependency of sorption to the two organoclays. The two organoclays manifested weaker sorption affinity but faster sorption kinetics for bulky AIOCs than commercial activated carbon, resulting from the high accessibility of sorption sites in the open, ordered clay interlayer. The findings of this study highlight the potential of using HDTMA- and PDADMA-exchanged montmorillonites as effective sorbents for AIOCs in water and wastewater treatments. 相似文献
403.
404.
405.
Chi-Sun Poon Shi-cong Kou Hui-wen Wan Miren Etxeberria 《Waste management (New York, N.Y.)》2009,29(8):2369-2377
Low grade recycled aggregates obtained from a construction waste sorting facility were tested to assess the feasibility of using these in the production of concrete blocks. The characteristics of the sorted construction waste are significantly different from that of crushed concrete rubbles that are mostly derived from demolition waste streams. This is due to the presence of higher percentages of non-concrete components (e.g. >10% soil, brick, tiles etc.) in the sorted construction waste.In the study reported in this paper, three series of concrete block mixtures were prepared by using the low grade recycled aggregates to replace (i) natural coarse granite (10 mm), and (ii) 0, 25, 50, 75 and 100% replacement levels of crushed stone fine (crushed natural granite <5 mm) in the concrete blocks. Test results on properties such as density, compressive strength, transverse strength and drying shrinkage as well as strength reduction after exposure to 800 °C are presented below. The results show that the soil content in the recycled fine aggregate was an important factor in affecting the properties of the blocks produced and the mechanical strength deceased with increasing low grade recycled fine aggregate content. But the higher soil content in the recycled aggregates reduced the reduction of compressive strength of the blocks after exposure to high temperature due probably to the formation of a new crystalline phase. The results show that the low grade recycled aggregates obtained from the construction waste sorting facility has potential to be used as aggregates for making non-structural pre-cast concrete blocks. 相似文献
406.
407.
环境行政管理:集中抑或分散 总被引:1,自引:0,他引:1
杜万平 《中国人口.资源与环境》2002,12(1):24-26
随着我国环境保护形势的变化 ,环境行政管理体制已对其缺乏适应性 ,并存在诸多问题 ,应进行环境行政管理模式的改革。为此 ,笔者联系世界各国的管理模式进行了分析和探讨 ,认为在横向管理权力地相对集中 ,纵向管理权力地相对分散的同时 ,建立各部门、各地区之间的协调机构的管理模式将是一种理性的选择。 相似文献
408.
409.
云南省丽江大地震及其诱发的崩塌滑坡灾害特征 总被引:21,自引:1,他引:21
1996年2月3日,云南省丽江县城以北40km发生7级强烈地震,这次地震在约12000km2范围内诱发了至少420处中小型崩塌和30处大中型滑坡,造成房屋倒塌、桥梁毁坏和公路堵塞。调查研究得出以下结论:(1)地震触发的崩塌滑坡分布在Ⅵ度区内,主要集中在主震震中东南部,接近表层构造断裂带和余震活动范围内;(2)崩塌主要发生在高陡斜坡的峡谷地带,滑坡多为复活型,部分为同发型和滞后型滑坡;(3)地形是控制崩塌滑坡分布位置的主导因素,崩塌多发生于大于60度斜坡中上部,滑坡发育于中缓斜坡(25°~45°);(4)滑坡影响区如遇充足的降雨可能进一步变形破坏,大量地裂隙孕育着新的崩塌滑坡,潜在危险性大。 相似文献
410.
Guoning Chen Liushu Pan Zhou Wan Qilin Feng Jue Wang Jianhua Xiong Shuangfei Wang Hongxiang Zhu 《环境科学学报(英文版)》2022,34(12):50-61
The widespread contamination of water systems with antibiotics and heavy metals has gained much attention. Intimately coupled visible -light-responsive photocatalysis and biodegradation (ICPB) provides a novel approach for removing such mixed pollutants. In ICPB, the photocatalysis products are biodegraded by a protected biofilm, leading to the mineralization of refractory organics. In the present study, the ICPB approach exhibited excellent photocatalytic activity and biodegradation, providing up to ∼1.27 times the degradation rate of sulfamethoxazole (SMX) and 1.16 times the Cr(VI) reduction rate of visible-light-induced photocatalysis . Three-dimensional fluorescence analysis demonstrated the synergistic ICPB effects of photocatalysis and biodegradation for removing SMX and reducing Cr(VI). In addition, the toxicity of the SMX intermediates and Cr(VI) in the ICPB process significantly decreased. The use of MoS2/CoS2 photocatalyst accelerated the separation of electrons and holes, with•O2– and h+ attacking SMX and e– reducing Cr(VI), providing an effective means for enhancing the removal and mineralization of these mixed pollutants via the ICPB technique. The microbial community results demonstrate that bacteria that are conducive to pollutant removal are were enriched by the acclimation and ICPB operation processes, thus significantly improving the performance of the ICPB system. 相似文献