基于数字色度学的有色透明溶液浓度快速检测方法

Study on rapid concentration detection of colored transparent solution based on digital chromatology

提出基于数字色度学的有色透明溶液浓度快速检测方法,并开发了配套的检测系统。依据朗伯-比尔吸收定律和RGB颜色模型推导出溶液色度值与浓度的定量关系;采用自行开发的检测系统进行了可行性实验,并在此基础上对稻米直链淀粉含量进行了检测实验,对方法的理论及实际检测效果进行了验证。结果表明:溶液色度值与质量浓度负指数相关;特征色度值Ci的变换lg(C0(iλ)/Ci)与质量浓度的线性相关系数>0.998 0,可用于样品浓度的准确测定;特征色度值Ci>160时,其与质量浓度的线性相关系数>0.980 0,可用于样品浓度预测或粗测。该系统可同时采集多个样品溶液的色度值,检测速度快;相同条件下多次采集的数据变异系数<4%,说明该系统操作具有可重复性;检测结果最大相对误差为4.4%,满足微量组分检测的准确度要求。该系统结构简单,易于操作,开发成本低。该方法可为现场快速检验、检测工作和在线智能化在线检测提供参考。

A new method based on the digital chromatology to detect the concentration of colored transparent solution was developed and the associated system was established. Based on the Lambert-Bill rule and the RGB model, the function between RGB value of solution and concentration was obtained. The experiments for the feasibility of this new approach were carried out using a self-designed detection system during which the precision and accuracy of the system were also investigated. The experimental results show that there exists a determined exponential relationship between RGB and the concentration; the relative coefficient between the transform of eigen-color value （lg（C0（λi）/Ci）） and c is bigger than 0. 998 0, which can be used to accurately determine the concentration of a solution sample; but if the eigen-color value is bigger than 160, without its transform, it is possible to predict the concentration of sample by just using the linear function between it and concentration. Using this system, the chroma values of ten samples can be obtained once and the variable coefficients are lower than 4% and the maximum of relative errors is 4.4%. This method and the system are available for field or on-line concentration detection.