氯化钠抑制下乙酸厌氧降解的动力学模型

作者利用五个实验室规模的完全混合反应器进行较长时间的半连续培养,研究在氯化钠抑制下乙酸盐的厌氧降解。结果表明,在不同条件下运行的反应器内,存在优势菌群的显著差异,因此在不同条件下运行的反应器对抑制有不同的响应。作者引入抑制因子的概念,建立了在氯化钠抑制下乙酸厌氧降解的动力学模型。同时指出反应器运行条件与菌群组成的联系以及菌群组成的差别对反应器运行状况的影响,在废水生物处理的动力学模型研究中应给予足够的重视。     

Uptake and distributions of polycyclic aromatic hydrocarbons in cultivated plants around an E-waste disposal site in Southern China

Environmental Science and Pollution Research - Polycyclic aromatic hydrocarbons (PAHs) in air, soil, and cultivated plants at e-waste disposal sites in Taizhou, Zhejiang Province, were determined...     

微酸多年卧孔菌产漆酶条件优化及其在染料脱色中的应用

微酸多年卧孔菌(Perenniporia subacida)产漆酶能力对生物漂白等研究具有重要意义.通过单因子和正交试验确定了微酸多年卧孔菌(菌株号:Dai 8224)的最适产酶条件:麦芽糖20 g/L,酵母浸粉5 g/L,pH 5.4,Cu2+2.0 mmol/L,培养温度24℃,转速160 r/min,接种量1.5%(V/V),此时酶活最高可达1.945 U/mL.单独使用微酸多年卧孔菌漆酶粗酶液对染料具有很好的脱色效果.该菌株对于50 mg/L杂环类染料中性红的脱色率可达98.3%,对偶氮染料刚果红的脱色率次之,为91.57%,对亚甲基蓝和铬天青的脱色率也都在80%以上.此外,其催化中性红脱色的最佳底物浓度为60 mg/L,脱色率达到99.42%,其中,生物降解作用占55.92%,菌体吸附作用占43.5%.结果表明该菌对多种染料脱色具有较大的应用潜力.图4表3参31     

臭氧和二氧化氯灭活水中病毒的研究

氯是世界上应用最广泛的饮用水消毒剂,但是它杀灭病毒的能力较差,消毒过程中还可能形成有毒的氯化有机物。本研究认为臭氧灭活病毒的作用迅速、浓度低、效率高,副作用较小,经臭氧消毒后的水无色、无臭、无三卤甲烷等有毒副产物。 二氧化氯也可以用作饮用水消毒剂。使用二氧化氯消毒产生的三卤甲烷要比氯消毒少得多;同时,二氧化氯不与水中常有的氨作用,形成消毒能力较差的氯氨。本研究表明,在大多数的饮用水pH范围内,二氧化氯是一种比氯性能良好的消毒剂。因此,臭氧和二氧化氯可以代替氯,单独地或与氯结合用于水的消毒。     

Distribution of aromatic amines,phenols, chlorobenzenes,and naphthalenes in the surface sediment of the Dianchi Lake,China

• The total organic pollutant concentrations in sediment were 27.4-1620 ng/g. • The phenol concentrations were relatively high in the sediment of the Dianchi Lake. • Average total concentrations decreased as follows: Caohai>Waihai>Haigeng Dam. • 1,4-dichlorobenzene, 3- or 4-methylphenol, 1,2,4-trichlorobenzene might be risks. Organic pollutants are widespread environmental pollutants with high toxicity, persistence, and bioaccumulation. Our aim was to investigate the distribution of aromatic amines, phenols, chlorobenzenes, and naphthalenes in the surface sediment of the Dianchi Lake, China. Nineteen surface sediment samples were collected from the Dianchi Lake, and 40 types of organic pollutants were analyzed via gas chromatography–mass spectrometry. The total organic pollutant concentrations in the surface sediment of the Dianchi Lake varied from 27.4 to 1.62 × 10³ ng/g. The concentrations of phenols were much higher than those in other water bodies but still within a controllable range, whereas the concentrations of the other organic pollutant classes were similar or even lower. The detection ratio of 3- or 4-methylphenol was the highest (100.00%) among the pollutants. The average total organic pollutant concentrations decreased in the following order: Caohai (540 ng/g)>the middle of Waihai (488 ng/g)>the edge of Waihai (351 ng/g)>Haigeng Dam (90.4 ng/g). Pearson analysis showed a strong correlation among 1-methylnaphthalene, 2-methylnaphthalene, 1,3-dinitronaphthalene, and 1,4-dinitronaphthalene (p<0.01). Caohai, the north lakeshore of Waihai and the south of Waihai showed higher risk because of high concentration; meanwhile, 1,4-dichlorobenzene, 3- or 4-methylphenol and 1,2,4-trichlorobenzene were more likely to cause risks.     

臭氧与几种酸性染料在水中的反应动力学研究及其反应过程分析

臭氧和臭氧与其它工艺的结合使用对处理印染工业废水具有巨大的潜力.本文研究了臭氧与三种酸性染料在水中的反应动力学,并对染料——酸性媒介深黄GG与臭氧的反应过程进行了探讨研究结果表明:1.臭氧与染料在水中的反应遵循二级反应动力学.反应动力学常数受染料分子结构的强烈影响;2.臭氧与偶氮类染料在水中反应时,偶氮键(-N=N-)断裂,可能产生硝基和亚硝基化合物,这类化合物对人有很强的毒性,在工程实践中应有所警惕.