全文获取类型
收费全文 | 445篇 |
免费 | 27篇 |
国内免费 | 214篇 |
专业分类
安全科学 | 36篇 |
废物处理 | 35篇 |
环保管理 | 38篇 |
综合类 | 266篇 |
基础理论 | 85篇 |
污染及防治 | 159篇 |
评价与监测 | 25篇 |
社会与环境 | 18篇 |
灾害及防治 | 24篇 |
出版年
2023年 | 15篇 |
2022年 | 17篇 |
2021年 | 20篇 |
2020年 | 22篇 |
2019年 | 20篇 |
2018年 | 24篇 |
2017年 | 24篇 |
2016年 | 26篇 |
2015年 | 42篇 |
2014年 | 37篇 |
2013年 | 54篇 |
2012年 | 50篇 |
2011年 | 38篇 |
2010年 | 33篇 |
2009年 | 29篇 |
2008年 | 26篇 |
2007年 | 39篇 |
2006年 | 17篇 |
2005年 | 16篇 |
2004年 | 10篇 |
2003年 | 13篇 |
2002年 | 20篇 |
2001年 | 8篇 |
2000年 | 10篇 |
1999年 | 17篇 |
1998年 | 8篇 |
1997年 | 6篇 |
1996年 | 8篇 |
1995年 | 10篇 |
1994年 | 6篇 |
1993年 | 8篇 |
1992年 | 7篇 |
1991年 | 1篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1981年 | 2篇 |
排序方式: 共有686条查询结果,搜索用时 109 毫秒
601.
Hengyi DUAN Xiaotu LIU Meilin YAN Yatao WU Zhaorong LIU 《Frontiers of Environmental Science & Engineering》2016,10(1):73-84
Volatile organic compounds (VOCs) and carbonyl compounds were measured both indoors and outdoors in 50 residences of Beijing in heating (December, 2011) and non-heating seasons (April/May, 2012). SUMMA canisters for VOCs and diffusive samplers for carbonyl compounds were deployed for 24 h at each site, and 94 compounds were quantified. Formaldehyde, acetone and acetaldehyde were the most abundant carbonyl compounds both indoors and outdoors with indoor median concentrations being 32.1, 21.7 and 15.3 μg·m−3, respectively. Ethane (17.6 μg·m−3), toluene (14.4 μg·m−3), propane (11.2 μg·m−3), ethene (8.40 μg·m−3), n-butane (6.87 μg·m−3), and benzene (5.95 μg·m−3) showed the high median concentrations in indoor air. Dichloromethane, p-dichlorobenzene (p-DCB) and toluene exhibited extremely high levels in some residences, which were related with a number of indoor emission sources. Moreover, isoprene, p-dichlorobenzene and carbonyls showed median indoor/outdoor (I/O) ratios larger than 3, indicating their indoor sources were prevailing. Chlorinated compounds like CFCs were mainly from outdoor sources for their I/O ratios being less than 1. In addition, indoor concentrations between two sampling seasons varied with different compounds. Carbonyl compounds and some chlorinated compounds had higher concentrations in the non-heating season, while alkanes, alkenes, aromatic compounds showed an increase in the heating season. Indoor concentration of VOCs and carbonyls were influenced by locations, interior decorations and indoor activities, however the specific sources for indoor VOCs and carbonyls could not be easily identified. The findings obtained in this study would significantly enhance our understandings on the prevalent and abundant species of VOCs as well as their concentrations and sources in Beijing residences. 相似文献
602.
Rui Duan Yun Lu Lingyan Hou Lina Du Lequn Sun Xingfan Tang 《Frontiers of Environmental Science & Engineering》2016,10(6):11
Many studies have focused on environmental estrogen-related diseases. However, no consistent gene markers or signatures for estrogenicity have been discovered in mammals. This study investigated the estrogenic effects of 17β-estradiol on the prostate in immature male mice. Consistent U-shaped responses were seen in bodyweight, ventral prostate epithelial morphology, and miRNA expression levels. Specifically, most estradiol regulated miRNAs were downregulated at low doses of estradiol (0.2 and 2 mg·kg–1), and whose expression returned to the control level at a larger dose (200 mg·kg–1). The function of these regulated miRNAs is related to the prostate cancer and PI3K-Akt signaling pathways, which is consistent with the function of estradiol. Furthermore, the miRNA-processing machinery, Drosha, in the prostate was also regulated in a similar pattern, which could be a part of the U-shaped miRNA expression mechanism. All of these data indicate that the prostate is a reliable organ for evaluating estrogenic activity and that the typical nonmonotonic dose-response relationship could be used as a novel biomarker for estrogenicity.
相似文献
603.
Yanqing Duan Aijuan Zhou Kaili Wen Zhihong Liu Wenzong Liu Aijie Wang Xiuping Yue 《Frontiers of Environmental Science & Engineering》2019,13(1):3
604.
Ab STEVELS Jaco HUISMAN Feng WANG Jinhui LI Boyang LI Huabo DUAN 《Frontiers of Environmental Science & Engineering》2013,7(4):475-482
This paper indicates that the performance of tack-back and treatment of electronic waste (e-waste) system can be improved substantially. This can be reached by better taking into account in a better way the big variety in material composition and potential toxicity of electrical and electronic products - from a technical, organizational and regulatory perspective. Realizing that there is no ‘one size fit for all’ and combining smart tailor made solutions with economic of sale will result in the best environmental gain/cost ratio. Several examples show how science and engineering have supported or will support this approach. 相似文献
605.
Geological phenomena (e.g. drastic sea level fluctuations during the Quaternary Ice Age in the Northern Hemisphere) have been demonstrated to intensively affect the biogeographic patterns and tempo-spatial compositions of genetic diversity of marine organisms. However, it is poorly understood whether contemporary factors such as oceanic surface currents have also shaped inter-regional population genetics of specific coastal marine flora, with or without limited dispersal capability. In this study, we determined mtDNA Cox1 gene sequences of the brown seaweed Sargassum fusiforme from nine populations along the Chinese coast and one population from the west coast of South Korea, in an effort to understand what factors are contributing to their current genetic structure and geographic distribution patterns. Genetic analyses indicated a deep genetic break between the Yellow-Bohai Sea (YBS) and the other two marginal seas, the East China Sea (ECS) and the South China Sea (SCS). In particular, the amount of genetic exchange from the SCS to each of the ECS and YBS was significantly higher than that from the opposite directions. Our analyses supports the hypothesis that biogeographic patterns of genetic variation in S. fusiforme are probably an interactive consequence of post-glacial colonization from two scattered refugia driven by the offshore Kuroshio Current and asymmetric gene flow among adjacent sea margins. 相似文献
606.
中国资源能源稀缺度因子及其在生命周期评价中的应用 总被引:1,自引:0,他引:1
在生命周期评价(Life Cycle Assessment, LCA)方法中,利用资源稀缺度因子,可以综合评价一个产品生命周期中总体的资源消耗水平。论文基于广泛采用的CML方法中的非生物资源消耗(Abiotic Depletion Potential, ADP)因子,通过引入中国的资源自给率修正,得出了中国非生物资源消耗因子(Chinese Abiotic Depletion Potential,CADP)及其指标。CADP因子可支持国内LCA研究和相关政策研究中的资源、能源消耗综合评价,同时也为其他国家或地区的资源评价提供了一种普遍适用的方法。案例研究表明,1 kWh电网电力的生命周期CADP指标为1.02 kg coal-R eq.,60.46%的贡献都来自于原煤资源的消耗,其次来自石油的消耗(11.63%),此外还包括基础设施建设中铜、镍等资源的消耗。 相似文献
607.
608.
阳离子表面活性剂处理油田含聚合物废水 总被引:1,自引:0,他引:1
以7种常见的阳离子表面活性剂为絮凝剂,考察对海上某油田含聚合物废水的处理效果.实验结果表明:一定浓度时,十四烷基三甲基溴化铵和十六烷基三甲基溴化铵有很好的絮凝效果:阳离子季铵盐表面活性剂加入到含聚合物废水中后,先会与连续水相中的水解聚丙烯酰胺(HPAM)发生静电中和作用,剩余的表面活性剂扩散至油水界面与界面处HPAM作用后破坏HPAM对油滴的稳定作用,从而达到絮凝效果;阳离子表面活性剂的加入量与含聚合物废水中HPAM的浓度密切相关. 相似文献
609.
Understanding the mechanism of arsenic (As) mobilization from sediments to groundwater is important for water quality management
in areas of endemic arsenic poisoning, such as the Datong basin in northern China. The bulk geochemistry analysis of sediment
samples from three 50-m boreholes drilled specifically for this study at As-contaminated aquifers, the groundwaters of which
have an As concentration up to 1060 μg/l, revealed that the average bulk concentrations of major and trace elements of the
samples are similar to those of the average upper continental crust. The average As content of the sediment samples (18.7 mg/kg)
is higher than that of modern unconsolidated sediments (5–10 mg/kg). Moreover, the abundance of elements varied with grain
size, with higher concentrations in finer fractions of the sediments, such as silt and clay. The concentration of NH2OH–HCl-extracted iron (Fe) strongly correlated with that of extracted As, suggesting that Fe oxyhydroxides may be the major
sink of As in the aquifer. The results of microcosm experiments showed that As mobilization from sediments to groundwater
is probably mainly related to changes in the redox conditions, with moderately reducing conditions being favorable for As
release from sediments into groundwater. 相似文献
610.