一种基于光谱的同步快速测定离子浓度方法

A Method of Fast Synchronic Determination of Mixed Ionic Concentration Based on Spectra

为了同步快速测定水中多种离子的浓度,提出了一种光学检测与综合数据处理相结合的方法。该方法基于分光光度法原理,能够快速测得混合离子光谱。用小波降噪、主成分分析降噪和差分降噪对测得数据进行综合处理。其中解决光谱重叠问题是提高测定精度的关键,目前多采用化学或物理的方法消除重叠,速度较慢;而采用待测多种离子的标准光谱,进行鲁棒(稳健)回归分析来消除重叠,其速度快,从软硬件两方面保证了快速性,且便于测量装置小型化。实测表明本方法测定精度高、速度快,同时能完成两种离子浓度的同步测定。

To fast synchronically measure a variety of ionic concentration, a method of combining optic detec- tion and compound data processing is discussed. Firstly, spectrum data are obtained by spectrophotometric method. Wavelet de-noising, PCA（ principal component analysis）de-noising and difference de-noising are used to process the measured data. Reducing ionic overlapping disturbance is important to improve the determination resolution. At present, the chemical and physical methods are numerously used to eliminate the overlap, which is slower. Now, standard spectrum and de-noising data, robust regression analysis are also used, which is faster. The hardware and software improves the determination speed, and it is easy to miniaturization. Practical deter- mination shows that the proposed method can achieve higher determination resolution, and it is faster. Simulta- neous determination of two ionic concentration is obtained.