全文获取类型
收费全文 | 323篇 |
免费 | 18篇 |
国内免费 | 142篇 |
专业分类
安全科学 | 14篇 |
废物处理 | 25篇 |
环保管理 | 17篇 |
综合类 | 204篇 |
基础理论 | 94篇 |
污染及防治 | 90篇 |
评价与监测 | 12篇 |
社会与环境 | 13篇 |
灾害及防治 | 14篇 |
出版年
2024年 | 1篇 |
2023年 | 9篇 |
2022年 | 13篇 |
2021年 | 20篇 |
2020年 | 15篇 |
2019年 | 20篇 |
2018年 | 20篇 |
2017年 | 15篇 |
2016年 | 18篇 |
2015年 | 24篇 |
2014年 | 21篇 |
2013年 | 26篇 |
2012年 | 18篇 |
2011年 | 15篇 |
2010年 | 28篇 |
2009年 | 18篇 |
2008年 | 19篇 |
2007年 | 12篇 |
2006年 | 16篇 |
2005年 | 4篇 |
2004年 | 14篇 |
2003年 | 14篇 |
2002年 | 4篇 |
2001年 | 13篇 |
2000年 | 9篇 |
1999年 | 9篇 |
1998年 | 18篇 |
1997年 | 17篇 |
1996年 | 17篇 |
1995年 | 8篇 |
1994年 | 11篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1985年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有483条查询结果,搜索用时 421 毫秒
22.
预处理后的活性污泥对锌吸附的研究 总被引:2,自引:0,他引:2
剩余活性污泥处理是当今的热点问题,从活性污泥资源化的角度出发,将活性污泥加工成为锌离子的生物吸附剂,比较了8种方法预处理后的活性污泥对锌的吸附效果,分析了这8种方法对污泥吸附能力的影响机理.对经过NaOH和H2O2处理的污泥的吸附特性和影响因素进行了研究,结果表明该吸附过程符合Psemio-seconal Order吸附动力学模型及Freunomch吸附等温模型,低pH不利于吸附,适当提高温度可以增强吸附效果,增加污泥吸附剂浓度可以增加金属离子去除率,但是单位质量吸附剂吸附金属离子的量减小.用红外光谱对比的手段对吸附机理进行了探讨,结果表明污泥颗粒表面一些含氮氧的基团对zn.'的络合作用是主要的吸附机理.该研究在污泥资源化和废水中锌离子的去除方面有重要意义. 相似文献
23.
Highly efficient conversion of sugarcane bagasse pretreated with liquid hot water into ethanol at high solid loading 总被引:1,自引:0,他引:1
Wen Wang Xinshu Zhuang Qiang Yu Jingliang Xu Wei Qi 《International Journal of Green Energy》2016,13(3):298-304
Liquid hot water (LHW), an environmental-friendly physico-chemical treatment, was applied to pretreat the sugarcane bagasse (SCB). Tween80, a non-ionic surfactant, was used to enhance the enzymatic hydrolysis of the pretreated SCB. It found that 0.125 mL Tween80 /g dry matter could make the maximum increase (33.2%) of the glycan conversion of the LHW-pretreated SCB. A self-designed laboratory facility with a plate-and-frame impeller was applied to conduct batch hydrolysis, fed-batch hydrolysis, and the process of high-temperature (50°C) fed-batch hydrolysis following low-temperature (30°C) simultaneous saccharification and fermentation (SSF) which was adopted to overcome the incompatible optimum temperature of saccharification and fermentation in the SSF process. After hydrolyzing LHW-pretreated SCB for 120 h with commercial cellulase, the total sugar concentration and glycan conversion obtained from fed-batch hydrolysis were 91.6 g/L and 68.3%, respectively, which were 9.7 g/L and 7.3% higher than those obtained from batch hydrolysis. With Saccharomyces cerevisiae Y2034 fermenting under the non-sterile condition, the ethanol production and theoretical yield obtained from the process of SSF after fed-batch hydrolysis were 55.4 g/L and 88.3% for 72h, respectively, which were 15.5 g/L and 24.7% higher than those from separate fed-batch hydrolysis and fermentation. The result of this work was superior to the reported results obtained from the LHW-pretreated SCB. 相似文献
24.
25.
Guor-Cheng Fang Yu-Chen Kuo Yuan-Jie Zhuang Yu-Cheng Chen 《Environmental monitoring and assessment》2014,186(7):4139-4151
This study characterized and discussed particulate ambient air particulate concentrations and seasonal variations for PM18, PM10, PM2.5, and PM1 during June 2013–July 2013 at this traffic sampling site. In addition, this study also characterized the ambient air particulates size distributions by using MOUDI-100S4 sampler to collect 1-day the ambient suspended particles (PM18, PM10, PM2.5, and PM1) at this sampling site. In addition, the study also showed that the main pollutants contributions were from traffic and residual areas. As for the pollutants seasonal concentrations variations, the results indicated that the average particle concentrations orders were all displayed as daytime?>?nighttime for PM18, PM10, PM2.5 and PM1 at this characteristic sampling site. The results further indicated that the mean highest of metal concentrations in this study indicated that the average metal concentration were all displayed as Mn?>?Cr?>?Ni?>?Pb?>?Cd for PM18, PM10, PM2.5 and PM1 on daytime and nighttime at this characteristic sampling site. 相似文献
26.
Dongqi Wang Yanling He Jidong Liang Pei Liu Pengyu Zhuang 《Environmental monitoring and assessment》2013,185(2):1041-1053
To study the status and source of aluminum (Al) contamination, a total of 21 sampling sites along six rivers near Xi’an City (Shaanxi province, China) were investigated during 2008–2010. The results indicated that the average concentration of total Al (Alt) in the six rivers increased by 1.6 times from 2008 to 2010. The spatial distribution of Alt concentrations in the rivers near Xi’an City was significantly different, ranged from 367 μg/L (Bahe River) to 1,978 μg/L (Taiping River). The Alt concentration was highest near an industrial area for pulp and paper-making (2,773 μg/L), where the Al level greatly exceeded the water quality criteria of both the USA (Criterion Continuous Concentration, 87 μg/L) and Canada (100 μg/L). The average concentration of inorganic monometric aluminum (Alim) was 72 μg/L which would pose threats to fishes and other aquatic lives in the rivers. The concentrations of exchangeable Al (Alex) in the sediment of the Taiping River sampled were relatively high, making it to be an alternative explanation of increasing Al concentrations in the rivers near Xi’an City. Furthermore, an increasing Al level has been detected in the upstream watershed near Xi’an City in recent years, which might indicate another notable pollution source of Al. 相似文献
27.
Liumeng Pan Liping Lu Jingpeng Wang Cunwu Zheng Yujie Fu Siyuan Xiao Yating Jin Shulin Zhuang 《Environmental Chemistry Letters》2017,15(4):673-678
The fungicide difenoconazole has been frequently detected in agricultural products, soils and surface waters, causing increasingly public concern due to toxicological properties. Although systemic triazole fungicides can inhibit the enzymatic activity of many CYP450 isozymes, how difenoconazole affects the human CYP3A4 still remains largely unknown. We thus investigated the effect of difenoconazole on normal mRNA expression and protein expression of human CYP3A4 by real-time quantitative PCR and western blot, respectively. Results show that the exposure to difenoconazole from 0.01 to 0.5 μM for 24 h down-regulates mRNA expression levels of human CYP3A4 in HepG2 cells. We also found that difenoconazole could inhibit the enzymatic activity of human CYP3A4 in a concentration-dependent mode. The IC50 of difenoconazole for inhibition of CYP3A4 activity is 0.41 µM, showing a stronger inhibitor in comparison with ketoconazole. Overall, our findings indicate the potential risk of difenoconazole for the disruption of human CYP3A4. 相似文献
28.
为了研究厌氧折流板反应器在常温下的启动情况,在22.5~30.2℃条件下,对不加填料的5隔室厌氧折流板反应器和加填料的4隔室复合式厌氧折流板反应器同步进行了启动实验。实验用水为高浓度淀粉废水,两反应器采用相同的启动策略,即梯度增加进水COD浓度与降低水力停留时间相结合的方式。两反应器有效容积均为47.8 L,启动初始负荷为0.6 kg COD/(m3.d),逐渐增加到10 kg COD/(m3.d)。实验表明,经过6个阶段87 d的运行,反应器启动完成,并成功培养出颗粒污泥,两反应器对COD的去除率都能达到85%以上。在启动过程中两反应器对COD的去除效率相近。 相似文献
29.
异波折板水解酸化-A~2O一体化反应器实验研究 总被引:1,自引:0,他引:1
设计了异波折板水解酸化-A2O一体化反应器,进行生活污水处理的实验研究。10个月的实验结果表明,系统的最佳水力停留时间(HRT)为8 h时,最适COD进水浓度为240~600 mg/L,最佳混合液回流比(r)-污泥回流比(R)为250%~100%。控制反应器于以上运行参数下,25±2℃所对应的COD、TN和TP去除率分别为96.84%、67.55%和81.92%。当温度降至7℃时,其COD、TP和TN分别降至86.35%、50.25%和65.68%。基于实验分析结果,阐明了一体化反应器高效性的机理在于异波折板水解酸化段具有高效传质特性和A2O段具有复合式活性污泥-接触氧化好氧池的特点。 相似文献
30.