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921.
近年来,我国不少地区饮用水水源水质日益恶化,水质净化面临新的问题。通过对微污染水源水处理技术的分析,阐明了微污染水处理的基本理论,探讨了强化传统处理工艺、预处理技术、深化处理技术的作用效果与机理,展望了我国饮用水源水处理发展趋势。 相似文献
922.
Wenjie Zhang Yao Zhang Wentao Su Yong Jiang Min Su Ping Gao Daping Li 《环境科学学报(英文版)》2014,26(4):885-891
The effects of cathode potentials and initial nitrate concentrations on nitrate reduction in bio- electrochemical systems (BESs) were reported. These factors could partition nitrate reduction between denitrification and dissimilatory nitrate reduction to ammonium (DNRA). Pseudomonas alcaliphilastrain MBR utilized an electrode as the sole electron donor and nitrate as the sole electron acceptor. When the cathode potential was set from -0.3 to -I.1 V (vs. Ag/AgC1) at an initial nitrate concentration of 100 mg NO~-N/L, the DNRA electron recovery increased from (10.76 ± 1.6)% to (35.06 ± 0.99)%; the denitrification electron recovery decreased from (63.42 ± 1,32)% to (44.33 ± 1.92)%. When the initial nitrate concentration increased from (29.09 ± 0.24) to (490.97 ± 3.49) mg NO3-N/L at the same potential (-0.9 V), denitrification electron recovery increased from (5.88 ± 1.08)% to (50.19 ±2.59)%; the DNRA electron recovery declined from (48.79 ±1.32)% to (16.02 ± 1.41)%. The prevalence of DNRA occurred at high ratios of electron donors to acceptors in the BESs and denitrification prevailed against DNRA under a lower ratio of electron donors to acceptors. These results had a potential application value of regulating the transformation of nitrate to N2 or ammonium in BESs for nitrate removal. 相似文献
923.
Lizhen Liu Boqiang Qin Yunlin Zhang Guangwei Zhu Guang Gao Qi Huang Xin Yao 《环境科学学报(英文版)》2014,26(8):1725-1732
Preliminary characterization of bound extracellular polymeric substances(bEPS) of cyanobacteria is crucial to obtain a better understanding of the formation mechanism of cyanobacterial bloom. However,the characterization of bEPS can be affected by extraction methods. Five sets(including the control) of bEPS from Microcystis extracted by different methods were characterized using three-dimensional excitation and emission matrix(3DEEM) fluorescence spectroscopy combined chemical spectrophotometry; and the characterization results of bEPS samples were further compared. The agents used for extraction were NaOH,pure water and phosphate buffered saline(PBS) containing cationic exchange resins,and hot water. Extraction methods affected the fluorescence signals and intensities in the bEPS. Five fluorescence peaks were observed in the excitation and emission matrix fluorescence spectra of bEPS samples. Two peaks(peaks T1 and T2) present in all extractions were identified as protein-like fluorophores,two(peaks A and C) as humic-like fluorophores,and one(peak E) as a fulvic-like substance.Among these substances,the humic-like and fulvic-like fluorescences were only seen in the bEPS extracted with hot water. Also,NaOH solution extraction could result in strong fluorescence intensities compared to the other extraction methods. It was suggested that NaOH at pH 10.0 was the most appropriate method to extract bEPS from Microcystis. In addition,dialysis could affect the yields and characteristics of extracted bEPS during the determination process. These results will help us to explore the issues of cyanobacterial blooms. 相似文献
924.
为了合理选择常村煤矿综掘面除尘的通风方式,本文根据煤矿中常用的通风方式和气固两相流的理论,利用fluent非稳态的数值模拟方法来模拟压入式和长压短抽两种不同通风方式下常村煤矿掘进面粉尘的运移规律以及司机处粉尘浓度分布,并进行了现场实测验证。结果表明:对于粉尘运移模型,采用非稳态的求解器要比稳态的求解器更加精确;在长压短抽通风方式下,涡流对粉尘运移影响较大,可以通过调整风速和除尘风机的负压来减小涡流的影响区域;采用长压短轴的通风方式比压入式通风方式在数值模拟情况下,前者比后者掘进机前部的粉尘浓度降低了22.2%,通过现场实测得到其降低了31.6%,巷道中部粉尘的平均浓度可由508mg/m3下降到185mg/m3,降幅为63.6%,表明长压短抽通风方式数值模拟和现场实测都要优于压入式通风方式;此外,需要在掘进机的前面和回风侧增加除尘措施,以确保司机处的粉尘浓度符合标准。 相似文献
925.
采用实验室测试和现场调查相结合的方法,测试了高性能聚乙烯纤维手套的防护性能,调查手套的适应性、防护时间和费用支出,探讨了其应用前景。 相似文献
926.
927.
928.
苯酚毒性大、难降解,是严重的环境污染物,同时也是环境监测的重要指标。文章介绍了用高效液相色谱荧光检测法测定环境水体中苯酚的分析方法。实验条件,色谱柱VP-ODS(150×4.6 mm,5 um);柱温25℃;流动相:V(甲醇)∶V(水)=46∶54,检测波长为λex/λem=215/300 nm,进样量20 uL。测定结果,苯酚的线性范围0.20~100 mg/L,r=0.999 3,检出限0.1 mg/L。表明该方法适用于对环境水体中苯酚的测定。 相似文献
929.
930.
姚斌 《安全.健康和环境》2013,13(4)
介绍了HSE管理信息系统的定义及其高效性、稳定性、标准性、安全性、整合性的特点,指出该系统与数据挖掘、系统集成和人工智能技术的结合将是未来的发展方向. 相似文献