光谱校正对溶解有机物三维荧光光谱特征影响  

Effect of Spectra Correction on the Fluorescence Characteristics of Dissolved Organic Matter

作　　者：吴华勇[1] 周泽宇[1] 王洪涛[1] 陆文静[1] 孙晓杰[2] 

机构地区：[1]清华大学环境学院,北京100084 [2]桂林理工大学环境科学与工程学院,广西桂林541004

出　　处：《光谱学与光谱分析》2012年第11期3044-3048,共5页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(40872151)资助

摘　　要：在三维荧光光谱(EEM)测定中,由仪器直接记录的光谱(称为未校正光谱)由于受荧光光度计光源灯或探测器等波长特性的影响,并不是荧光物质本身的真实光谱,研究了光谱校正对腐殖酸和色氨酸EEM光谱特征以及传统寻峰法和新兴FRI分析法结果的影响,结果表明:校正后,Ex/Em=220～450/250～500nm范围内荧光强度降低,Em<250nm范围内荧光强度增大,腐殖酸荧光峰明显"蓝移"。基于寻峰法的荧光指数(FI)和腐殖化指数(HIX)明显减小,自生源指数(BIX)略增;基于FRI分析法的反映各区域标准体积百分比PⅠ,n,PⅡ,n和PⅢ,n明显上升,而PⅣ,n和PⅤ,n显著下降。因此,进行光谱校正是获得真实光谱谱图及光谱特征不可或缺的一部分。The Excitation-emission matrix（EEM） fluorescence spectra of dissolved organic matter（DOM） are not only dependent on the chemical structure of DOM as well as the local chemical environment around the DOM,but also dependent on the instrument employed for the analysis.Thus,in order to get the real spectra of the DOM,spectra correction of the effect of the instrument-specific response is necessary.However,some studies corrected DOM spectra,while still some studies didn＇t,leading to inconformity when comparing the data and the results from different groups.The present work evaluated the effect of spectra correction on the fluorescence characteristics of DOM.The results demonstrated that DOM spectra differed significantly after correction.Fluorescence intensities showed a decrease in the range of Ex/Em=220~450/250~500 nm,while an increase at Em〈250 nm after correction.Fluorescence intensity ratio（FI） and humification index（HIX） derived from peak picking method showed a decrease after correction,while biological index（BIX） increased slightly.PⅠ,n,PⅡ,n and PⅢ,n derived from FRI analysis exhibited a significant increase,while PⅣ,n and PⅤ,n decreased.The results suggest that spectral correction should be included when analyzing the properties and trends of the DOM using EEM.

关 键 词：溶解性有机物 三维荧光光谱 光谱校正 荧光指数 FRI分析法 

分 类 号：X830.2[环境科学与工程—环境工程]