高岭土控制污泥膨胀的研究

活性污泥膨胀一直是困扰人们的难题。本实验以人工合成污水为底物,利用间歇式反应器(SBR)通过投加高岭土来研究污泥膨胀的控制情况。同时分析活性污泥中的丝状菌形态。结果表明,投加高岭土来控制污泥膨胀效果非常显著,对出水水质影响甚微。     

Impact of silver nanoparticles on natural marine biofilm bacteria

There has been a recent increase in the use of silver nanoparticles (Ag NPs) in a wide range of consumer products due to their highly effective antimicrobial properties. However, Ag NPs give cause for concern since their wide use makes them likely to be released into aquatic ecosystems and potentially affect natural bacterial communities. In this study marine biofilms were grown in situ in a coastal site (Singapore Harbour) and exposed in the laboratory for a further 24 h to 0-2000 μg L⁻¹ of well characterised Ag NPs. Increasing concentrations of Ag NPs caused a significant decrease in biofilm volume and biomass, and Ag uptake by biofilms per unit of volume was also dependent on concentration. Terminal fragment length polymorphisms and subsequent cluster and phylogenetic analysis showed the presence of major bacterial groups in biofilms irrespective of treatment with Ag NPs. This implies that even at the highest concentrations studied these taxonomic groups were not displaced. Nevertheless, biofilm succession was impeded on Ag NP treated biofilms, affecting the relative abundance of major bacterial groups in the biofilm community, with potential longer term effects on biofilm development and function.