油类污染物三维荧光光谱的瑞利散射消除方法

Elimination method of Rayleigh scattering for three dimensional fluorescence spectra of oil pollutants

荧光光谱中存在的瑞利散射对三维荧光光谱检测有较大影响,消除散射对光谱分析具有重要意义。针对油类污染物样品溶液光谱,分别采用空白扣除法、Delaunay三角形内插值法和缺损数据重构(MDR)法对三维荧光光谱的瑞利散射进行处理。结果表明:采用空白扣除法无法将瑞利散射完全消除,在光谱中仍可见显著的散射干扰,激发、发射解析光谱在边缘区域出现明显失真;采用Delaunay三角形内插值法消除瑞利散射,分解的激发、发射光谱与真实光谱吻合较好,预测浓度曲线与真实浓度曲线趋势一致,浓度值偏差较小;而采用MDR法消除瑞利散射,激发、发射光谱解析解与浓度解都与真实值高度吻合。定性与定量分析均表明,MDR法能够有效去除瑞利散射,还原三维荧光光谱的有效信息,是一种比较理想的瑞利散射消除方法。

Rayleigh scattering in fluorescence spectra has great influence on the detection of three-dimensional fluorescence spectrum.Eliminating scattering is of great significance to spectral analysis.According to the spectra of oil pollutant sample solution,the Rayleigh scattering of the three-dimensional fluorescence spectra was eliminated by blank subtraction method,Delaunay triangle interpolation method and Missing Data Recovery(MDR)method respectively.The studies show that the Rayleigh scattering can not be eliminated completely by using the blank subtraction method,and the scattering interference can still be seen in the spectrum,the excitation and the emission analytical spectrum appeared obvious distortion in the edge region.After the Rayleigh scattering was eliminated by the Delaunay triangle interpolation method,the excitation and emission spectra of the decomposition agree well with the real spectrum.The predicted concentration curve was consistent with the true concentration curve,and the concentration value deviation was small.When Rayleigh scattering was eliminated by MDR method,the analytical solution of excitation spectrum,emission spectrum and the solution of concentration were in good agreement with the real value.Both qualitative and quantitative analysis show that the MDR method can effectively remove Rayleigh scattering and reduce the effective information of three-dimensional fluorescence spectrum,which is an ideal method for Rayleigh scattering elimination.