不同滤料滤池处理微污染水源水生产性试验研究

对比研究不同滤料滤池对浊度、有机物、三卤甲烷前体物的去除效果,并结合三维荧光光谱技术分析其对荧光溶解性有机物的去除效果。试验结果表明,炭砂滤池、炭滤池以及砂滤池对浊度的去除效果良好,炭砂滤池对浊度控制效果最佳;炭砂滤池和炭滤池对TOC、COD_(Mn)和UV_(254)的去除效果相当,明显优于砂滤池;炭砂滤池和炭滤池对三卤甲烷前体物的去除效果均好于砂滤池,在水温较高的条件下,效果更为明显;从三维荧光光谱技术分析,滤池进出水主要以芳香性蛋白质类物质和溶解性微生物代谢产物类物质组成;炭砂滤池和炭滤池对荧光溶解性有机物的去除效果相当,去除率分别为20.18%和21.50%;砂滤池对荧光溶解性有机物的去除率仅为6.15%。

Synthesis of aligned carbon nanotube with straight-chained alkanes by nebulization method

Aligned carbon nanotubes(CNTs)were synthesized by nebulized spray pyrolysis of solutions of organometallics in carbon precursor solvents.Four types of straight-chained alkanes including n-pentane,n-hexane,n-heptane and n-octane were used as precursor solvents for synthesis of aligned CNTs.The results from scanning electron microscopy,transmission electron microscopy and Raman spectroscopy show that the CNTs obtained from them have different diameters and degrees of graphitization. It is found that the n-heptane is the most suitable for the growth of aligned CNTs with high quality and yield.The thermodynamic properties of precursory carbon sources such as boiling point and formation enthalpy are considered to play a decisive role in the synthesis of CNTs.It will be very helpful for the controllable preparation of aligned CNTs at relatively low cost.

2005-2008年长沙市自来水水质监测情况动态分析

目的了解长沙市市政供水自来水水质情况,为改善水质及水体环境治理提供科学依据。方法按全国疾病预防控制机构工作规范,对全市6家市政供水自来水厂的水质以及19个管网末梢水监测点的水质连续4年进行监测及对结果进行分析。结果长沙市生活饮用水合格率从高到低为管网末梢水(99.30%)>出厂水(98.33%)>水源水(6.25%),其中水源水水质较差,主要超标为微生物指标;出厂水氯仿含量高于水源水氯仿含量,差异有统计学意义(P<0.05);出厂水氯仿与pH、COD成正性相关(差异有统计学意义P=0.018、0.014),与余氯成负性相关(差异无统计学意义P=0.055),可能受检测仪器误差、水体中有机前体物含量、pH值的变化有关。结论长沙市生活饮用水总体水质较好;对余氯及氯仿等氯化消毒副产物的含量进行跟踪监测,并适当控制投氯量;湘江水源水的环境保护及治理有待加强。