摘要
利用灭菌灯照射,HPLC法检测,研究了MCRR在紫外光(主要发射波长为254nm)照射下的光降解行为。结果表明,在254nm紫外光下,MCRR的光降解和异构化作用同时发生,整个过程不能用准一级反应动力学方程描述。光照强度是影响反应速率的重要因素,温度对反应速率也有较大影响,光强增加和温度的升高均可加速MCRR降解。当温度为25℃、光强为425μW·cm-2时,MCRR的降解半衰期约为2min。pH对MCRR降解的影响不十分显著,但在偏酸性条件比中性和碱性条件有利于降解。
Decomposition behavior of microcystins by UV irradiation was examined using germicidal lamp as light source, and concentrations of the toxins were determined by high performance liquid chromatography. The results showed that photolysis as well as isomerization of the toxin took place simultaneously, and the course did not follow pseudo- first order reaction kinetics. Enhanced irradiation intensity could strongly accelerate the reaction, and high temperature could also promote the reaction. The half- life of microcystins by 425 μ W· cm- 2 UV(254 nm) irradiation at 25 ℃ was estimated to be 2 min. At low pH condition, the toxins exhibited a little more suitable for degradation than at either neutral or alkaline conditions, although the difference was not remarkable.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2003年第3期283-285,共3页
Journal of Agro-Environment Science
基金
招标项目(DCH-01-001)
国家863计划项目(2001AA641030)