摘要
有色溶解性有机质(CDOM)是水环境中多种生物地球化学过程的驱动者和参与者,结构复杂。尽管对CDOM稳态光谱的研究较多,但是对其激发态特别是激发单重态(^(1)CDOM^(*))的研究鲜有报道。该文在亚纳秒水平上研究了^(1)CDOM^(*)的衰减动力学过程,拟合结果显示^(1)CDOM^(*)的寿命小于10 ns。分析了通过积分荧光衰减动力学曲线和利用稳态荧光光谱仪2种方法得到的CDOM稳态荧光光谱的差别,并解释了两者之间的差异主要来自检测器的检测性能和是否进行光谱校正。相比于强度权重平均寿命(τ_(f)),振幅权重平均寿命(τ_(α))可以更加准确地描述不同发射波长下CDOM的荧光衰减过程。
Chromophoric dissolved organic matter(CDOM)is the driver and participant of biogeochemical cycle in water environment,with complex structure.Although there are many studies on the steady-state spectrum of CDOM,there are few reports on the excited states,especially the excited singlet state(^(1)CDOM^(*)).The decay kinetics of^(1)CDOM^(*)is studied at sub-nanosecond level.The fitting results show that the lifetime of^(1)CDOM^(*)is less than 10 ns.The difference between the steady-state fluorescence spectrum obtained by integrating the fluorescence decay kinetic curve and the steady-state fluorescence spectrum directly measured by the steady-state fluorescence spectrometer is compared,and it is explained that the difference between the two methods is mainly due to the detection performance of the detector and whether the spectrum is corrected.Compared with intensity weighted average lifetime(τ_(f)),amplitude weighted average lifetime(τ_(α))is more accurate to describe the fluorescence decay process of CDOM at different emission wavelengths.
作者
刘娟
周睿雅
张旭
LIU Juan;ZHOU Ruiya;ZHANG Xu(School of Resource and Environmental Science,Wuhan University,Wuhan 430079,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2021年第7期159-165,共7页
Environmental Science & Technology
基金
国家自然科学基金(22076148)
关键词
有色溶解性有机质
激发单重态
时间分辨荧光
稳态荧光
平均寿命
chromophoric dissolved organic matter
the excited singlet state
time resolved fluorescence
steady-state fluorescence
average lifetime
