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   2327篇
  免费   107篇
  国内免费   847篇
安全科学   175篇
废物处理   145篇
环保管理   164篇
综合类   1322篇
基础理论   426篇
污染及防治   744篇
评价与监测   82篇
社会与环境   59篇
灾害及防治   164篇
  2024年   1篇
  2023年   42篇
  2022年   123篇
  2021年   106篇
  2020年   65篇
  2019年   77篇
  2018年   84篇
  2017年   113篇
  2016年   121篇
  2015年   155篇
  2014年   166篇
  2013年   237篇
  2012年   189篇
  2011年   208篇
  2010年   165篇
  2009年   140篇
  2008年   163篇
  2007年   133篇
  2006年   115篇
  2005年   84篇
  2004年   66篇
  2003年   88篇
  2002年   66篇
  2001年   59篇
  2000年   62篇
  1999年   82篇
  1998年   61篇
  1997年   58篇
  1996年   50篇
  1995年   50篇
  1994年   27篇
  1993年   38篇
  1992年   31篇
  1991年   24篇
  1990年   14篇
  1989年   4篇
  1988年   5篇
  1987年   1篇
  1984年   5篇
  1981年   2篇
  1958年   1篇
排序方式: 共有3281条查询结果,搜索用时 296 毫秒
831.
针对三鑫矿山采用充填采矿法在回采矿房过程中留存大量底柱不能及时回采,后期回采存在安全隐患等问题,对矿山地质条件进行调查,利用Mathew法对矿房稳定性进行研究,结合矿山实际开采计划,对桃花嘴矿区-570~-720四个中段制定了协同回采方案,并利用FLAC3D数值模拟软件对协同回采方案进行可行性探讨.研究表明,为了保持采...  相似文献   
832.
Environmental Science and Pollution Research - Year-round film mulching in winter wheat field facilitates rainwater storage in summer fallow period and reduces water evaporation in growing reason,...  相似文献   
833.
Environmental Science and Pollution Research - In this work, a novel composite, ball-milled biochar (BMB) encapsulated in calcium-alginate (CA) beads (CA-BMB), was synthesized as an alternative...  相似文献   
834.
Li  Xiaoping  Cai  Yue  Liu  Dongying  Ai  Yuwei  Zhang  Meng  Gao  Yu  Zhang  Yuchao  Zhang  Xu  Yan  Xiangyang  Liu  Bin  Yu  Hongtao  Mielke  Howard W. 《Environmental science and pollution research international》2019,26(6):5564-5576
Environmental Science and Pollution Research - Utilization of microbes is one of the most promising methods to remediate potentially toxic metals (PTMs) from soil. In this study, a systematic...  相似文献   
835.
The intensity of environmental regulation (ERI) affects the short-term effect of the level of green mining (GML), and which structure determines the long-term mechanism. Based on the panel data from 2001 to 2015, with the dynamic panel model and system GMM estimation method were employed to test the influence of heterogeneous environmental regulation on green mining and its transmission mechanism. The results show that, there is a “U” type nonlinear relationship between the ERI and GML. The direct effect of command-control-based (CAC) and the market incentive-based (MBI) environmental regulation on green development of mining shows the characteristics of inhibition and promotion. There is a “U” type of indirectly moderating effect between technological innovation and the energy consumption structure on the GML. The technological innovation promotes the green development of the mining industry only after pass the inflection point of MBI, while the CAC plays a significant guiding role in upgrading of the energy consumption structure. There is an inhibition and promotion effect of MBI on the GML in the southeast coastal area, and the CAC is not significantly. Meanwhile, both of the ERI shows no positive effects in the central and western inland region.  相似文献   
836.
采用磷化工行业的固体废物泥磷液相催化氧化氮氧化物。实验结果表明,该方法是可行且有效的。随着温度的升高,泥磷吸收液的脱硝效率提高,当温度达到泥磷熔点时脱硝效率最佳。泥磷吸收液的脱硝效率随固液比的增大而有所下降,而随着NO体积分数和气体流量的增大,泥磷吸收液的脱硝效率呈先升后降的趋势。各因素对脱硝率的影响大小顺序为:气体流量>反应温度>固液比>NO体积分数。在反应温度60 ℃、固液比1∶4、NO体积分数0.03%、气体流量0.3 L/min的最佳工艺条件下,反应160 min的平均脱硝率可达97.38%。  相似文献   
837.
A bibliometric analysis based on the Science Citation Index Expanded (SCI-EXPANDED) from the Web of Science was carried out to provide insights into research activities and tendencies of the global biodiesel from 1991 to 2015. The document type and language, characteristics of publication outputs, Web of Science categories, journals, countries, institutions, author keyword and most cited articles were emphasized. The results indicated that annual output of the related scientific articles increased steadily. The top six categories focus on different aspects of biodiesel research. Bioresource Technology and Fuel were the two most frequent journals in the field of biodiesel research. The USA took a leading position and had the highest h-index (108) out of 122 countries/territories, followed by China and Brazil. Finally, author keywords and most cited articles were analyzed, indicating that microalgae, Jatropha curcas, vegetable oil and waste cooking oil are the most general raw materials for biodiesel production.  相似文献   
838.
In this reported study, a renewable and eco-friendly blood meal-based (BM) bio-adhesive was developed for the plywood fabrication. Polyvinyl alcohol (PVA), sodium dodecyl sulphate (SDS), and triglycidylamine (TGA) were respectively employed as emulsifier, denaturant and crosslinking agent to modify the BM adhesive. Three-ply plywood was manufactured and its wet shear strength was tested. The solid content, residual rate, functional groups, thermal degradation behavior, and cross section micromorphology of the resulting adhesives were characterized in detail. The experimental results showed that PVA prevented the BM agglomeration, SDS unfolded the structure of protein and then TGA reacted with the exposed active groups in the BM protein molecules, forming a cross-linked structure. As a result, the thermal stability of the modified BM adhesive was improved and the cross section of the cured adhesive was more homogeneous, which enhanced the performance of the adhesive. Consequently, the wet shear strength of the plywood bonded by modified BM adhesive markedly increased by 388% to 1.27 MPa. Compared with soy bean meal-based adhesive, a higher protein content and hydrophobic amino acids content of BM are benefit for fabricating high performance bio-based adhesive, which rendered the BM adhesive practical for plywood industrial application.  相似文献   
839.
高菲 《环境与发展》2020,(1):45-46,49
汽车涂装VOCs的大量排放严重污染环境且危害人体健康,需对其排放水平加以控制。根据汽车涂装VOCs的产生环节,从原料替代、工艺改善和VOCs治理方式等方面探究其减排途径,提高治理水平。采用环保型涂料从源头减少VOCs排放,优化涂装工艺、采用高涂着率喷枪,优化喷枪与涂装面角度、雾化压力、涂装面距离等可以提高喷涂效率,减少过量喷涂。就治理方式而言,吸附技术适用于中低浓度需回收的VOCs气体,燃烧技术几乎不产生二次污染物,吸附浓缩+燃烧技术因治理效果好而被广泛应用。  相似文献   
840.
宫照  高波 《环境与发展》2020,(2):131-132
以第一次全国地理国情普查与基础性地理国情监测数据为数据源,开展西藏芒康滇金丝猴国家级自然保护区内2015、2016、2017、2018年自然保护区建设与管理情况监测,分别从人工地物、林草资源、露天采掘场等方面进行统计,分析人类活动对自然保护区内的生态系统胁迫以及区内生态恢复情况等。  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