杜利特尔分析与多元校正法应用于紫外分光光度法同时测定NO_3^-和NO_2^-

Application of the Algorithm of Doolittle Analysis and Multivariate Calibration to Simultaneous UV-Spectrometric Determination of NO_3^- and NO_2^-

杜利特尔法是一种数值分析方法,它通过对矩阵进行三角分解,从而简化运算,提高准确度。将杜利特尔法与多元校正相结合,用于紫外光谱重叠比较严重的NO3-和NO2-两组分体系谱图,测定的相对误差在-4.56%~9.02%范围,明显好于P矩阵计算结果(-21.03%~36.40%),表明杜利特尔多元校正法在解析多组分重叠谱图方面具有一定的优越性。

The Doolittle numerical analytical method together with the multivariate calibration method was applied to the UV-spectrophotometric determination of NO-3 and NO-2,to overcome the difficulty of overlapping of absorption spectra of the 2 anions in the spectral range of 190 nm to 230 nm,which was the cause of impossibility of their direct determination.Data of 1st derivative of the absorbance values of NO-3 and NO-2 were used for data treatment in Doolittle analysis and multivariate calibration.As shown by the experimental results,values of relative deviation of the analytical results obtained by the present method were in the range from-4.56% to 9.02%,which were much more precise than the values of relative deviation in the range from-21.03% to 36.40% as obtained by the P-matrix method.It was shown evidently that the proposed method was superior to be used for dissolution of spectral overlapping.