Impacts of CuO, TiO2, SiO2 nanoparticles on biological phosphorus removals.

[[abstract]]本研究探討三種不同奈米金屬微粒（奈米氧化銅、奈米二氧化鈦及奈米二氧化矽），對活性污泥除磷機制之影響。實驗結果顯示，奈米氧化銅濃度達5 mgl-1已開始抑制磷蓄積菌之除磷能力；奈米二氧化鈦1000 mgl-1(有照光組) 之除磷能力抑制率較1000 mgl-1(未照光組)高；奈米二氧化矽濃度達500 mgl-1 始抑制除磷，達1000 mgl-1抑制情形較明顯。 統計檢定結果顯示，添加三種奈米微粒對於磷蓄積菌之比攝磷率、PHAs合成/分解率及肝醣分解/合成率幾乎都有顯著影響，僅添加奈米二氧化鈦之肝醣分解率及添加奈米二氧化矽之PHAs / 肝醣合成率無顯著影響，其抑制程度大致為奈米氧化銅>奈米二氧化矽?奈米二氧化鈦。本研究亦發現奈米顆粒對除磷的影響，主要來自金屬離子的釋出及活性氧化物種 (Reactive Oxygen Species, ROS)的生成，其釋出量與生成量大致會隨奈米金屬濃度增加而有增加之趨勢。[[abstract]]This study explored the impacts of CuO, TiO2, SiO2 nanoparticles on biological phosphorus removal. Experimental results showed that the phosphorus removal ability of phosphorus accumulating organism (PAO) was initially inhibited when CuO nanoparticle concentration was 5 mgl-1. The inhibition of phosphorus removal for 1000 mgl-1 of TiO2 with sunlight was higher than without sunlight case. The inhibition of phosphorus removal began at SiO2 nanoparticle concentration of 500 mgl-1. Inhibition became apparent when SiO2 nanoparticle concentration was up to 1000 mgl-1 . Statistical analysis showed that the three kinds of nanoparticles significantly affected the PAO’s metabolisms, including phosphorus release, PHA synthesis/degradation, and glycogen degradation/synthesis, except for the cases of glycogen degradation for TiO2 nanoparticle and PHA/ glycogen synthesis for SiO2 nanoparticle. The order of the inhibition degree of nanoparticles for PAO was CuO> SiO2> TiO2. This study also found that the influence of nanoparticles on PAO’s metabolisms mainly resulted from the release of ionic metals and the formation of reactive oxidation substances (ROS). The concentration of ionic metals and ROS increased with increasing nanoparticle concentration.[[note]]碩