Resolution of Closely Overlapping Spectra by Kalman Filtering in Fluorospectrophotometry
Zhang Jingyu , Yang Jinfu, Ren Ying, Zhang Yan.Fu Lianshe, Lei Zhongli (Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022)
The emission spectra of the complex of Zn and Al with 7-iodo-8-hydroxyquinoline-5-sulfonic acid -CTMAB are closely overlapping. The synchronous excitation technique could not thoroughly separate the overlapping spectra although it indeed increased the separation degree from 0. 26 in the conventional spectra to 0. 38 in the synchronous spectra. On the other hand, when the intensity ratio of Al to Zn at the central wavelength of complex was below 1, the Kalman filtering technique was capable of resolving this system. When the intensity of Al at the central wavelength was higher than that of Zn, the accuracy and precision of the estimates for Zn concentration became worse. In this case, the combination of synchronous excitation and Kalman filtering could much improve the analytical results.