摘要
采用三维荧光指纹光谱技术对河流溶解性有机物荧光特征进行了研究。结果表明,污染河流中的溶解性有机物主要有腐殖质和蛋白质两类,类腐殖质荧光峰λ激发/λ发射为250/460nm(A1),220/400nm(A2)和325/420nm(C);类蛋白质荧光峰λ激发/λ发射为285/357nm(T1),230/360nm(T2)。支流的类蛋白质荧光峰T1和T2由于生活污水的排放,其荧光强度都有明显增强。Fe3+离子在支流与干流汇合后浓度增加到支流的30倍,相应的类腐殖质荧光峰A1也发生了明显蓝移现象,而其他荧光峰则没有明显的偏移。激发波长较长的类腐殖质C,A1和类蛋白质T1荧光强度由于稀释及Fe3+等金属离子猝灭而明显降低,以至荧光峰消失。而较低激发波长的类蛋白质T2和UV类腐殖质A2荧光强度和荧光峰位置相对比较稳定,不容易受到溶液化学条件影响。激发波长220～230nm荧光团可以用来示踪污染河流溶解性有机物。
Fluorescence fingerprint technique was used to characterize dissolved organic matter （DOM） in river from different sources. The results showed that two types of DOM fluorescence signals were observed in river water： a humie-like fluorescence with three maxima at λex/λem =250/460 nm（A1）, 220/400 nm（A2） and 325/420 nm（C） ; and a protein-like fluorescence with two maxima at λex/λem =230/360 nm（T2） and 285/357 nm（T1）. The intensity of both of protein-like fluorescence distinctly increased because of the domestic wastewater drainage in the tributary stream. After the tributary converges into the main stream, the Fe^3＋ concentration in the main stream is 30 times as much as that of tributary stream, and the visible blue-shift of humie-like fluorescence occurred while the others didn＇t occur. The intensity of all types of fluorescence decreased from source to estuary resulting from different solute chemistry. However, the intensities of humic-like fluorescence C, Al and protein-like fluores- cence T2 at the longer excitation wavelength decreased significantly because of dilution from main river stream and complexation of humic-like with Fe^3＋ , thus the peaks disappeared at the estuary while the fluorescence peaks at the shorter excitation wavelength were relatively stable on which the river solute chemistry had little effect. Therefore, the fluorophores at the shorter excitation wavelength of 220-230 nm area potential tool to determine the sources of DOM in polluted river.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2008年第2期347-351,共5页
Spectroscopy and Spectral Analysis
基金
国家“863”项目(2002AA601120)
国家自然科学基金项目(50238020和50378048)资助
关键词
荧光指纹
溶解性有机物
类蛋白质荧光团
类腐殖质荧光团
污染
Fluorescence fingerprint
Dissolved organic matter
Protein-like fluorophore
Humic-like fluorophore
Pollution
