全文获取类型
收费全文 | 2880篇 |
免费 | 372篇 |
国内免费 | 1073篇 |
专业分类
安全科学 | 427篇 |
废物处理 | 117篇 |
环保管理 | 253篇 |
综合类 | 2110篇 |
基础理论 | 411篇 |
污染及防治 | 535篇 |
评价与监测 | 151篇 |
社会与环境 | 170篇 |
灾害及防治 | 151篇 |
出版年
2024年 | 8篇 |
2023年 | 57篇 |
2022年 | 198篇 |
2021年 | 172篇 |
2020年 | 166篇 |
2019年 | 138篇 |
2018年 | 157篇 |
2017年 | 181篇 |
2016年 | 161篇 |
2015年 | 200篇 |
2014年 | 211篇 |
2013年 | 276篇 |
2012年 | 293篇 |
2011年 | 272篇 |
2010年 | 261篇 |
2009年 | 206篇 |
2008年 | 189篇 |
2007年 | 212篇 |
2006年 | 192篇 |
2005年 | 142篇 |
2004年 | 102篇 |
2003年 | 87篇 |
2002年 | 88篇 |
2001年 | 58篇 |
2000年 | 74篇 |
1999年 | 53篇 |
1998年 | 32篇 |
1997年 | 43篇 |
1996年 | 33篇 |
1995年 | 21篇 |
1994年 | 13篇 |
1993年 | 14篇 |
1992年 | 7篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1983年 | 1篇 |
排序方式: 共有4325条查询结果,搜索用时 15 毫秒
31.
16 priority polycyclic aromatic hydrocarbons (PAHs) were determined in water samples from the Jinsha River (Panzhihua part), Southwest China. Total dissolved PAH concentrations varied from 21.89 microg l(-1) to 382.8 microg l(-1). It was found that the concentration of PAHs decreased along the flow direction due to the higher density distribution of coal chemical industry in the upstream of our study rivers. The pollution levels in our study area are significantly higher than previously reported values in other waters both in China and other countries. The predominance of benzo[k]fluoranthene and indeno[1,2,3-cd]pyrene was clearly observed in all water samples. On average these two compounds accounted for 98.3% of the total dissolved PAH concentration in water. The results showed the positive correlations among total dissolved PAHs, benzo[k]fluoranthene and indeno[1,2,3-cd]pyrene, which suggested that these two predominant PAHs have similar source and environmental behaviors in our study area. When compared with the survey results of organic micropollutants two decades ago, it was found that hydrocarbon pollution both predominated and even increased with the development of coal chemical industry in this area during the past 20 years. The results therefore provide important information on the current contamination status of a key industrial city in China, and points to the need for urgent action to investigate the relationship between the PAH composition and concentration in water from the Jinsha River and the wastewater discharge from coal chemical industry, and to identify the source, transport pathway and fate of PAHs in the area. It should then be necessary to adopt appropriate and instant measures to control the pollution around this area. 相似文献
32.
33.
Adsorption of zinc on manganite(γ-MnOOH): particle concentration effect and adsorption reversibility
The adsorption and desorption processes of Zn(Ⅱ) on τ-MnOOH as a function of particle concentrations (Cp) were studied. An obvious Cp effect was observed in this adsorption system. The degree of adsorption hysteresis increased greatly with the increasing of Cp, indicating that the extent of the real metastable-equilibrium states deviating from the ideal equilibrium state was enhanced with the increasing of Cp. The Cp-reversibility relationship confirmed the metastable-equilibrium adsorption (MEA) inequality (Pan, 1998a), which was the core formulation of the MEA theory. Because the MEA inequality was based on the basic hypothesis of MEA theory that adsorption densitιy ι is not a state variable, the Cp-reversibility relationship gave indirect evidence to the basic hypothesis of MEA theory. 相似文献
34.
采用边际机会成本理论,对自然资源定价的原理和方法进行阐述,并比较了各种方法在实际应用中的适用条件,以及相互之间的优劣,为自然资源开发中的环境损失估算提供理论支持. 相似文献
35.
随着石油化学工业的迅速发展,研究易燃、易爆物品的环境风险,对其进行风险评价,变得越来越重要。而危害范围的确定,对环境风险评价结果及降低风险所采取措施的合理性和可行性,起着决定性作用。现以一实例,通过计算,介绍易燃、易爆物品、如汽、柴油、液化气储罐的环境风险评价中危害范围的确定。 相似文献
36.
MethaneemissioninaricefieldofThailand¥RongXiang;Chuen-HowNg(EnvironmentalEngineeringProgram,SchoolofEnvironment,ResourcesandD... 相似文献
37.
38.
39.
21世纪水处理厂考察报告 总被引:2,自引:0,他引:2
评介了美国 2 1世纪水处理厂处理和回收城市污水的总体方案、处理工艺、处理效果、处理水应用以及所取得的环境效益、社会效益和经济效益 ,其建厂目的体现了美国治理环境的战略思想 ,其工艺、装备和整体技术代表了美国环境污染综合整治的先进水平 ,有值得借鉴之处。 相似文献
40.
介绍了回收磺酸盐生产工艺 ,对其装置的产品成本进行了测算 ,并对盈亏平衡及其敏感性进行了分析 ,进而确定了主要经济指标。 相似文献