丁基羟基茴香醚的太赫兹时域光谱检测与分析

利用太赫兹时域光谱（THz-TDS）技术对食品添加剂丁基羟基茴香醚（BHA）及其与聚乙烯不同配比的混合物进行了检测，获得了其在0.2-2.6THz波段的吸收谱和折射率谱。实验结果表明,在此波段内该物质有三个明显的吸收峰，分别位于0.64THz，1.14THz和1.81THz，该指纹谱可用于THz波段该物质的检测与识别。此外，利用最小二乘法对混合物太赫兹光谱峰位的吸收系数和质量分数进行线性拟合，结果表明聚乙烯中丁基羟基茴香醚的含量与太赫兹光谱的相关系数大于0.98。最后，用密度泛函理论对单分子丁基羟基茴香醚进行了数值计算，表明太赫兹指纹谱与分子构型和分子内部运动有关系。

Terahertz time-domain spectroscopy detection and analysis of butyl hydroxy anisole

The terahertz (THz) spectra of butyl hydroxy anisole (BHA) and its mixtures were measured in the frequency range of 0.2 - 2.6 THz by the THz time-domain spectroscopy. The results show that there are three distinctive absorption peaks in this frequency range, which were found at 0.64 THz, 1.14 THz and 1.81 THz. It can be used to identify this substance. In addition, the terahertz spectra of BHA mixture were analyzed by the least squares method. The results show that the correlation between terahertz absorption coefficient and the mass fraction of BHA is larger than 0.98. Finally, the numerical calculations based on the density functional theory are carried out for the single-molecule butyl hydroxy anisole.The results show that the terahertz absorption peaks have relationship with molecular conformation and molecular motion inside.