多维漫透射光谱提高复杂混合溶液分析能力

多维漫透射光谱技术利用传统的近红外透射测量方式，增加一维扫描装置，获得透射方向上的径向光谱，并利用多点漫透射光谱对复杂混合溶液进行成分分析。实验设计了基于氙灯光源、精密电控平移台和光谱仪的检测装置，选用Intralipid-20%，India Ink和C₆H₁₂O₆共配制225种成分含量不同的混合溶液，分别测量距其透射中心点0～5 mm(间隔0.25 mm)范围内的20点漫透射光谱信号，以偏最小二乘回归算法对单点和多点漫透射光谱信号进行建模分析。实验得到India Ink含量和Intralipid-20%含量随漫透射光位置点的增加建模及预测的精度提高，C₆H₁₂O₆含量随漫透射光位置点的增加建模及预测精度没有明显变化。结果表明，增加不同位置信息的漫透射光谱信号，能够提高复杂混合溶液中强吸收物质和强散射物质的信噪比，对于弱吸收弱散射物质有望在提升系统精度的前提下提高其预测能力。

Improving Component Analysis Ability of the Complex Mixed Solutions by Multi-Dimensional Diffuse Transmittance Spectrometry

The multi-dimensional diffuse transmittance spectrums were collected by the traditional near-infrared transmittance method combined with a scanning device, and then used for component analysis of the complex mixed solution. A xenon light, an electric control translation stage and a spectrometer were gathered to set up a device; Intralipid-20%, India-ink and C₆H₁₂O₆ were used to prepare 225 kinds of complex mixed solutions; the diffuse transmittance spectrums were measured at 20 points off the transmission center distributed from 0~5 mm (interval 0.25 mm); the single and multi-point diffuse transmittance spectrums were analyzed by partial least squares regression for modeling and prediction. The results show that the modeling and prediction accuracy of the concentrations of the intralipid-20% and India-ink increased with the growing of the transmittance points, but the concentration of the C₆H₁₂O₆ did not increase. It is proved that the spectrums collected by different points can raise the signal to noise radio of the strong absorption and scattering substance, and the signal to noise radio of the weak absorption and scattering substance would be improved by increasing the current system accuracy.