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排序方式: 共有233条查询结果,搜索用时 15 毫秒
131.
This research investigated the effects of ciprofloxacin(CIP)(0.5, 5, and 20 mg/L) on SBR systems under different carbon source conditions. Microbial community abundance and structure were determined by quantitative PCR and high-throughput sequencing, respectively.The biodegradation production of CIP and possible degradation mechanism were also studied. Results showed that CIP had adverse effects on the nutrient removal from wastewater.Compared with sodium acetate, glucose could be more effective...  相似文献   
132.
Ou HX  Wang Q  Xue YL  Pan JM  Du DL  Yan YS 《Water environment research》2011,83(12):2148-2153
Performance and characteristics of biosorption of Pb(II) had been studied in a batch system using the fungal strain biomass, KC-2. The biosorption performance was investigated by analysing the effects of such factors as the initial pH, initial Pb(II) concentration, and contact time at 303 K. The maximum Pb(II) adsorption was obtained at pH 5.0. The experimental data were described by the pseudo first-order, pseudo second-order and intraparticle diffusion kinetic models, and were closely followed the pseudo second-order kinetic model. The equilibrium experimental data were well fitted to Langmuir model and the maximum biosorption capacity was 84.03 mg g(-1). The adsorption mechanism was examined by FTIR, SEM and EDAX analysis. Results indicated that carboxylic, hydroxyl and amine groups were involved in the biosorption and ion exchange mechanism existed.  相似文献   
133.
筛选高效破乳剂,采取更加合理有效的加药方式,提高脱水效果,降低生产成本至关重要。河南油田井楼油矿针对稠油筛选出高效破乳剂,通过管道破乳应用,得出:FS-21二代破乳剂脱水效果明显比一代有较大提高,原油含水率较低;并且在站外加药,脱水效果明显高于站内加药,药剂用量要比站内少;使用的160多天内FS-21二代破乳剂适用性良好。进一步提高了稠油整体脱水效果,取得了明显的经济效益。  相似文献   
134.
英语电影教学是走在前端的一项多媒体教学尝试。语言学习轻松、直观,内容生动、丰富,在减轻学生语言学习焦虑及培养学生语言的应用能力,了解西方社会文化、历史等方面起到了有效的促进作用。  相似文献   
135.
Fenton体系降解水中偶氮染料的研究   总被引:1,自引:0,他引:1  
研究了Fenton体系对于水溶液中偶氮染料橙G(orange G,OG)的降解,反应30 min后,在[Fe2+]0=0.1mmol/L、[H2O2]0=10 mmol/L、pH=3.0的条件下,初始浓度为20 mg/L的OG的去除率达到99%以上。与H2O2相比,OG的降解速率随着Fe2+不同投加量的变化更为敏感。Fe2+和H2O2初始浓度较高时,反应过程中的Fe2+的浓度维持在一个较低的水平,OG的降解速率较快。腐殖酸对OG在Fenton体系中的降解影响表现出明显的阻碍作用,并且随着腐殖酸浓度的增加,抑制作用越来越大。  相似文献   
136.
通过不同泥石流容重、不同堆积区坡度条件、不同水槽坡度条件的泥石流连续堆积实验共3组106次实验,定量地探讨了粘性泥石流扇状地发展过程的阶段性及其特征。以泥石流扇状地纵、横方向的平均堆积坡度为依据,将粘性泥石流扇状地的发展过程划分为三个发展阶段。第一阶段以扇状地在纵、横方向快速发展为特征。第二阶段扇状地纵向不再发展,以横向发展为主。第三阶段以扇状地纵向发展为主,横向发展缓慢。  相似文献   
137.
通过有机改性剂在液液萃取和固相萃取条件下水中有机氯农药的提取效率比对分析,首次探讨了有机改性剂对水中有机氯农药提取效率的影响。结果表明,(1)液液萃取前处理水样中不加有机改性剂、固相萃取前处理水样中添加一定量有机改性剂时,水中有机氯农药的提取效率较高;(2)采用正交实验优化水中有机氯农药固相萃取的提取效率实验表明,有机改性剂添加量对其影响大于有机改性剂种类对其影响;最佳优化方案为水样中添加1%甲醇时,提取效率最高。  相似文献   
138.
Total HCHs' and total DDTs' levels in surface sediments (SS) ranged from 0.5 to 17.5 ng g−1 and from 0.9 to 33.1 ng g−1, averaged 6.0 and 8.2 ng g−1, respectively. Total HCHs' and total DDTs' levels in suspended particulate matters (SPM) varied from 6.2 to 14.8 ng g−1 with a mean value of 12.3 ng g−1 and were from 3.4 to 25.7 ng g−1 with an average of 16.4 ng g−1, respectively. Lindane is the main HCHs' source and continuing use in the Yangtze Delta areas of ‘pure’ γ-HCH (lindane) rather than technical HCH (a mix of largely α- and some γ-HCH). DDTs in SS are mainly accumulated in history. However, high DDT fractions in SPM are indicators of new input of typical dicofol type DDT from 2002 to 2004. It can be seen that most samples from the Yangtze estuary were in ranges where adverse biological effects are expected, either occasionally or frequently.  相似文献   
139.
四川甘孜达曲各目弄巴沟泥石流及其防治对策   总被引:2,自引:2,他引:0  
各目弄巴沟为雅砻江支流达曲的一级支沟,该沟地处川西高山高原区,处于南水北调西线一期达曲工程区内,曾发生过严重的泥石流灾害,直接威胁公路、村庄、学校、小水电站、桥梁等的安全.该沟泥石流具有规模大,危害严重、冲淤强烈、容重大,固体物质粒径粗等特征.在分析了该沟泥石流的特征基础上,预测了泥石流灾害的发展趋势,并提出了泥石流减灾防灾对策.  相似文献   
140.
Ou X  Chen S  Quan X  Zhao H 《Chemosphere》2008,72(6):925-931
Relationship between the photoinductive activity and the properties of humic acids (HA) fractions were investigated with and without Fe(III). Three fractions were separated based on the molecular weight (M(w)) and were obtained following the order of M(w): F(A)>F(B)>F(C). Compared to F(A) and F(B), photodegradation of atrazine under simulated sunlight was much faster in solution containing F(C), whose structure was dominated by greater aromaticity, more oxygen groups and fluorophores. The interaction of HA fractions and Fe(III) was studied using fluorescence spectrometry and F(C) had the largest quenching constant. The capacity of electron transfer, estimated from the amount of photoformed Fe(II), was also highest for F(C). Thus, the Fe(III)-F(C) complex was efficient in phototransformation of atrazine in nearly neutral aqueous solutions. These results suggest that the aromaticity and oxygen groups content of HA exert great influence on the binding ability of metals and on the fate of pollutants in natural waters.  相似文献   
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