全文获取类型
收费全文 | 1535篇 |
免费 | 62篇 |
国内免费 | 600篇 |
专业分类
安全科学 | 116篇 |
废物处理 | 92篇 |
环保管理 | 128篇 |
综合类 | 869篇 |
基础理论 | 269篇 |
污染及防治 | 566篇 |
评价与监测 | 45篇 |
社会与环境 | 43篇 |
灾害及防治 | 69篇 |
出版年
2024年 | 2篇 |
2023年 | 25篇 |
2022年 | 73篇 |
2021年 | 64篇 |
2020年 | 37篇 |
2019年 | 33篇 |
2018年 | 52篇 |
2017年 | 76篇 |
2016年 | 69篇 |
2015年 | 61篇 |
2014年 | 121篇 |
2013年 | 148篇 |
2012年 | 148篇 |
2011年 | 114篇 |
2010年 | 108篇 |
2009年 | 109篇 |
2008年 | 117篇 |
2007年 | 104篇 |
2006年 | 88篇 |
2005年 | 74篇 |
2004年 | 34篇 |
2003年 | 59篇 |
2002年 | 57篇 |
2001年 | 46篇 |
2000年 | 44篇 |
1999年 | 58篇 |
1998年 | 50篇 |
1997年 | 41篇 |
1996年 | 39篇 |
1995年 | 37篇 |
1994年 | 22篇 |
1993年 | 25篇 |
1992年 | 20篇 |
1991年 | 13篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1988年 | 8篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
排序方式: 共有2197条查询结果,搜索用时 15 毫秒
141.
Rui Wan Yuyin Yang Weimin Sun Zhao Wang Shuguang Xie 《Environmental science and pollution research international》2014,21(4):3175-3181
The objective of the present study was to investigate the impact of ammonia and nitrate nitrogen sources on simazine biodegradation by Arthrobacter sp. strain SD1 and the community structures of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in non-agricultural soil. Soil microcosms with different treatments were constructed for herbicide biodegradation test. The relative abundance of the strain SD1 and the structures of AOA and AOB communities were assessed using quantitative PCR (q-PCR) and terminal restriction fragment length polymorphism (TRFLP), respectively. The co-existence of two inorganic nitrogen sources (ammonia and nitrate) had certain impact on simazine dissipation by the strain SD1. Bioaugmentation could induce a shift in the community structures of both AOA and AOB, but AOA were more responsive. Nitrogen application had significant impacts on AOA and AOB communities in bioaugmented soils. Moreover, in non-bioaugmented soil, the community structure of AOA, instead of AOB, could be quickly recovered after herbicide application. This study could add some new insights towards the impacts of nitrogen sources on s-triazine bioremediation and ammonia-oxidizing microorganisms in soil ecosystem. 相似文献
142.
143.
针对无锡某废纸造纸企业产生的污水经厌氧-好氧-化学混凝处理后,出水在放流池产生结垢现状,对各段污水中主要离子浓度进行跟踪分析,并对结垢的组分、结垢原因、机理和防治结垢对策进行了探讨。结果表明:垢样的主要成分为CaCO3;污水中含有较高浓度的钙离子和碳酸氢根离子是导致结垢的主要原因,较高的水温、pH值、流速、流动状态、池壁的粗糙程度以及PAC的投加对结垢也有一定的影响;最佳防治对策为使用Ca(OH)2+PAM代替PAC+PAM混凝,保证COD达标排放同时,也解决了出水结垢问题。 相似文献
144.
生物阴极式碳纸隔膜微生物燃料电池的反硝化和产电性能 总被引:1,自引:0,他引:1
为了探讨生物阴极式廉价隔膜微生物燃料电池(microbial fuel cell,MFC)的基本性能,首先以生物反硝化作用为基础构建了生物阴极MFC,并进一步以涂布聚四氟乙烯(PTFE)的廉价碳纸代替昂贵的质子交换膜(PEM)构建碳纸隔膜生物阴极式MFC。研究结果显示,对于生物阴极式MFC,阴极室中最适宜反硝化细菌生长的NO-3-N浓度为99.2 mg/L,此时输出电压最高可达0.11 V,1 h内NO-3-N的去除率达到80.0%,COD去除率为62.8%;以涂PTFE的碳纸代替PEM的生物阴极式MFC与有PEM的MFC最高输出电压基本一致(均达到0.22 V,外阻500Ω),但碳纸隔膜MFC的产电更稳定。结果验证了廉价隔膜生物阴极式MFC的可行性,并为其应用于污水脱氮奠定基础。 相似文献
145.
生物法同时脱硫脱硝试验研究 总被引:1,自引:0,他引:1
采用轻质陶粒生物滴滤塔处理摸拟燃煤烟气中二氧化硫和氮氧化物的试验研究,探讨生物法同时脱硫脱硝的影响因素及生物降解宏观动力学。研究结果表明,生物法能有效同时去除烟气中的二氧化硫和氮氧化物,烟气同时脱硫脱硝效率分别可达99.9%和88.9%。为获得最佳烟气同时脱硫脱硝效果,二氧化硫和氮氧化物进气负荷应分别<140 g/(m3·h)和20 g/(m3·h),循环液pH=7~8,空床停留时间为30.28 s,喷淋密度为8.81 L/(m3·h)。 相似文献
146.
Yang-ying Zhao Fan-xin Kong Zhi Wang Hong-wei Yang Xiao-mao Wang Yuefeng F. Xie T. David Waite 《Frontiers of Environmental Science & Engineering》2017,11(6):20
This study was conducted to assess the merits and limitations of various high-pressure membranes, tight nanofiltration (NF) membranes in particular, for the removal of trace organic compounds (TrOCs). The performance of a low-pressure reverse osmosis (LPRO) membrane (ESPA1), a tight NF membrane (NF90) and two loose NF membranes (HL and NF270) was compared for the rejection of 23 different pharmaceuticals (PhACs). Efforts were also devoted to understand the effect of adsorption on the rejection performance of each membrane. Difference in hydrogen bond formation potential (HFP) was taken into consideration. Results showed that NF90 performed similarly to ESPA1 with mean rejection higher than 95%. NF270 outperformed HL in terms of both water permeability and PhAC rejection higher than 90%. Electrostatic effects were more significant in PhAC rejection by loose NF membranes than tight NF and LPRO membranes. The adverse effect of adsorption on rejection by HL and ESPA1 was more substantial than NF270 and NF90, which could not be simply explained by the difference in membrane surface hydrophobicity, selective layer thickness or pore size. The HL membrane had a lower rejection of PhACs of higher hydrophobicity (log D>0) and higher HFP (>0.02). Nevertheless, the effects of PhAC hydrophobicity and HFP on rejection by ESPA1 could not be discerned. Poor rejection of certain PhACs could generally be explained by aspects of steric hindrance, electrostatic interactions and adsorption. High-pressure membranes like NF90 and NF270 have a high promise in TrOC removal from contaminated water. 相似文献
147.
148.
Yingyi Zhang Senchao Lai Zhen Zhao Fobang Liu Hongwei Chen Shichun Zou Zhiyong Xie Ralf Ebinghaus 《Chemosphere》2013
An intensive campaign was conducted in September 2012 to collect surface water samples along the tributaries of the Pearl River in southern China. Thirteen perfluoroalkyl acids (PFAAs), including perfluorocarboxylates (PFCAs, C4–C11) and perfluorosulfonates (PFSAs, C4, C6–C8, and C10), were determined using high-performance liquid chromatography/negative electrospray ionization–tandem mass spectrometry (HPLC/(-)ESI–MS/MS). The concentrations of total PFAAs (ΣPFAAs) ranged from 3.0 to 52 ng L−1, with an average of 19 ± 12 ng L−1. The highest concentrations of ΣPFAAs were detected in the surface water of the Dong Jiang tributary (17–52 ng L−1), followed by the main stream (13–26 ng L−1) and the Sha Wan stream (3.0–4.5 ng L−1). Perfluorooctanoate (PFOA), perfluorobutane sulfonate (PFBS), and perfluorooctane sulfonate (PFOS) were the three most abundant PFAAs and on average accounted for 20%, 24%, and 19% of ΣPFAAs, respectively. PFBS was the most abundant PFAA in the Dong Jiang tributary, and PFOA was the highest PFAA in the samples from the main stream of the Pearl River. A correlation was found between PFBS and PFOA, which suggests that both of these PFAAs originate from common source(s) in the region. Nevertheless, the slope of PFBS/PFOA was different in the different tributaries sampled, which indicates a spatial difference in the source profiles of the PFAAs. 相似文献
149.
Zhen Hu Jian Zhang Shanping Li Huijun Xie 《Environmental science and pollution research international》2013,20(2):1059-1069
Wastewater treatment is an important source of nitrous oxide (N2O), which is a strong greenhouse gas and dominate ozone-depleting substance. The purpose of this study was to evaluate the effect of carbon source on N2O emission from anoxic/oxic biological nitrogen removal process. The mechanisms of N2O emission were also studied. Long-term experiments were operated to evaluate the effect of three different carbon sources (i.e., glucose, sodium acetate, and soluble starch) on N2O emission characteristics. And batch experiments, in the presence or absence of specific inhibitors, were carried out to identify the sources of N2O emission. The ammonia-oxidizing bacteria (AOB) and denitrifiers community compositions under different circumstances were also analyzed based on which the underlying mechanisms of N2O emission were elucidated. The conversion ratios of N2O in reactors with glucose, sodium acetate, and soluble starch were 5.3 %, 8.8 %, and 2.8 %, respectively. The primary process responsible for N2O emission was nitrifier denitrification by Nitrosomonas-like AOB, while denitrification by heterotrophic denitrifiers acted as the sink. Reactor with sodium acetate showed the highest N2O emission, together with the highest nitrogen and phosphate removal ratios. Carbon source has a significant impact on N2O emission quantity and relatively minor effect on its production mechanism. 相似文献
150.