全文获取类型
收费全文 | 487篇 |
免费 | 31篇 |
国内免费 | 194篇 |
专业分类
安全科学 | 43篇 |
废物处理 | 20篇 |
环保管理 | 36篇 |
综合类 | 288篇 |
基础理论 | 87篇 |
污染及防治 | 168篇 |
评价与监测 | 21篇 |
社会与环境 | 24篇 |
灾害及防治 | 25篇 |
出版年
2024年 | 1篇 |
2023年 | 13篇 |
2022年 | 29篇 |
2021年 | 19篇 |
2020年 | 21篇 |
2019年 | 22篇 |
2018年 | 16篇 |
2017年 | 24篇 |
2016年 | 35篇 |
2015年 | 23篇 |
2014年 | 35篇 |
2013年 | 59篇 |
2012年 | 44篇 |
2011年 | 43篇 |
2010年 | 41篇 |
2009年 | 43篇 |
2008年 | 29篇 |
2007年 | 30篇 |
2006年 | 40篇 |
2005年 | 18篇 |
2004年 | 13篇 |
2003年 | 17篇 |
2002年 | 13篇 |
2001年 | 8篇 |
2000年 | 16篇 |
1999年 | 15篇 |
1998年 | 8篇 |
1997年 | 3篇 |
1996年 | 5篇 |
1995年 | 7篇 |
1994年 | 9篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 7篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
排序方式: 共有712条查询结果,搜索用时 250 毫秒
501.
The α-pinene ozonolysis under the different environmental conditions were observed in a smog chamber. The second-order rate constant(k) was determined to be(7.25 ± 0.06) ×10~(–17)cm~3/(molecule·sec) under 20% of relative humidity(RH) and room temperature. RH showed a marked influence on the α-pinene ozonolysis. The value of k increased with RH increase, which was 1.6 times faster at RH = 80% than that at RH = 20%. Additionally, the value of k apparently changed in the presence of the aerosol particles. The diesel soot increased the k value. The fly ash prohibited the reaction, however, H_2SO_4-treated fly ash promoted the reaction. The information of products gained using FT-IR and SPAMS showed that pinonic acid, 10-hydroxy-pinonic acid and pinic acid could be generated during the α-pinene ozonolysis. Water molecules could take part in the formation of the products, and play a vital role in the degradation of α-pinene. The atmospheric residence time calculation showed that the ozonolysis in the atmosphere is an important way of the α-pinene consumption as compared to that reacted with OH during daytime. The results suggested that the degradation of α-pinene via the ozonization in the atmosphere may be affected greatly by RH, as well as the presence of aerosol particles. The ozonolysis reaction may be an important way of the α-pinene consumption during daytime. 相似文献
502.
JSP技术及其在安全管理信息系统中的应用 总被引:4,自引:2,他引:4
基于B/S模式并结合JSP(JavaServerPagesTM)技术 ,实现省、市职能部门对企业安全生产监督管理及安全信息共享平台。政府职能部门能够及时监管各地安全动态、发布公告和指令、校验特种作业人员和注册安全主任资格等 ;用户能进行事故隐患和执法监督行为投诉、事故快报、安全技术咨询、地方或行业法规标准查询等活动。从而 ,达到构建安全管理、安全技术服务、安全信息发布、事故预防集成系统的目的。 相似文献
503.
504.
我国热带季风区的“林-胶-茶生态模式” 总被引:1,自引:0,他引:1
本文是南海农场建设林胶茶模式16年总结。本场位于海南岛东北部重风害的草原台地。1958年建场,原以油棕为主,1975年改变方针,建林胶茶模式。经16年实践,显示出其优势和效益。比胶茶纯作提高经济效益40—200%和土地利用率50%以上,解决了劳动就业问题,改善了环境。其模式是我国热带地区减灾稳产,合理利用自然资源的一种有效模式。 相似文献
505.
浅谈突发性环境污染事故的应急监测预案 总被引:1,自引:0,他引:1
日本福岛核电厂由于地震引起的海啸发生放射性物质外泄事故,从而引发对于突发性环境污染事故的处理处置的关注,以突发性环境污染事故救援工作和应急处理处置的关键——应急监测入手,阐述了应急监测的基本、特殊要求和任务,具体说明了制定应急监测预案及预案的基本步骤和相关组织机构的职责,进一步明确了突发性环境污染事故应急监测预案在应急监测中的重要性,拟为突发性环境污染事故应急监测工作及应急监测预案的编制今后的理论与应用研究提供参考。 相似文献
506.
Rongchang Wang Xinmin Zhan Yalei Zhang Jianfu Zhao 《Frontiers of Environmental Science & Engineering in China》2011,5(1):48-56
Nitrogen removal performance and nitrifying population dynamics were investigated in a redox stratified membrane biofilm reactor
(RSMBR) under oxygen limited condition to treat ammonium-rich wastewater. When the NHt4+-N loading rate increased from 11.1±1.0 to 37:2 ± 3:2 gNHt4+-N·m−2·d−1, the nitrogen removal in the RSMBR system increased from 18.0±9.6 mgN·d−1 to 128.9±61.7 mgN·d−1. Shortcut nitrogen removal was achieved with nitrite accumulation of about 22:3 ± 5:3 mgNO2−-N·L−1. Confocal micrographs showed the stratified distributions of nitrifiers and denitrifiers in the membrane aerated biofilms
(MABs) at day 120, i.e., ammonia and nitrite oxidizing bacteria (AOB and NOB) were dominant in the region adjacent to the
membrane, while heterotrophic bacteria propagated at the top of the biofilm. Real-time qPCR results showed that the abundance
of amoA gene was two orders of magnitude higher than the abundance of nxrA gene in the MABs. However, the nxrA gene was always detected during the operation time, which indicates the difficulty of complete washout of NOB in MABs. The
growth of heterotrophic bacteria compromised the dominance of nitrifiers in biofilm communities, but it enhanced the denitrification
performance of the RSMBR system. Applying a high ammonia loading together with oxygen limitation was found to be an effective
way to start nitrite accumulation in MABs, but other approaches were needed to sustain or improve the extent of nitritation
in nitrogen conversion in MABs. 相似文献
507.
A new magnesium alloy anode is based on an environmentally friendly electrode that contains none of mercury, lead and chromate, but it can enhance the electric properties of alloy significantly. Magnesium alloy adding eco-friendly elements Zn-In-Sn which was developed by orthogonal design were obtained by two casting methods. The effect of additive elements on performance of electrode material was studied. The effects of elements addition and casting method on electric properties and corrosive properties of Mg-Zn-In-Sn alloys were investigated by using electrochemical measurements, corrosive tests and observation of surface structure. The results show that Mg-Zn-In-Sn alloy anode has higher electromotive force and more stable work potential than that commercial magnesium alloy AZ91. It is suitable for anode material of magnesium battery for its small hydrogen evolution, less self-corrosion rate and easy to shed corrosive offspring off. 相似文献
508.
文章报道了利用一种新型的环境矿物材料一羟基磷灰石处理实验室高浓度铅、镉污水的方法,该方法与《环境水质监测质量保证手册》中的消石灰处理法相比具有去除速度快、经济有效、无二次污染、安全环保等显著优点。本文还采用消石灰处理法对一次处理后的废水的上清液进行二次处理,这样能使实验室含高浓度的铅、镉废水,在处理后达到地表水三级质量标准。 相似文献
509.
510.