Study of UV-Visible Internal Reflection Spectrometer with Variable Angle of Incidence

研制了可变入射角的紫外可见光内反射光谱仪。研究了该光谱仪的一些特性。由于采用卤素灯作为光源，光学元件含有光纤，入射角显示出-lt；正负-1.5ﾟ的发散。除了在临界角附近的入射角范围内，这种发散对内反射光谱测量没有影响。利用不被玻璃吸附的染料溶液，测试了内反射光谱的光程(有效厚度)与反射吸光度之间的关系，该光程随入射角的变化而变化。结果表明，反射吸光度与有效厚度成正比，比例常数等于染料溶液的摩尔吸收系数。这一事实表明，所制造的光谱仪具有预期的性能。在阳离子表面活性剂存在下，用光谱仪研究了水溶性卟啉在玻璃上的吸附。界面反射光谱的原位观察表明，水溶性的葡聚糖苷被吸附在玻璃-溶液界面上。吸附的pH依赖性表明，吸附的物种是卟啉的去质子化形式，玻璃表面的电荷对卟啉在高pH溶液中的吸附行为有很大的影响。结果表明，本文研制的内反射光谱仪可用于固液界面的原位观测。此外，还将内反射光谱应用于液-液界面的研究

The UV-visible internal reflection spectrometer with variable angle of incidence was manufactured. Some features of the spectrometer were investigated. Because a halogen lamp was used as the light source and the optics contained optical fibers, the angle of incidence showed a divergence of <plus-minus>1.5ﾟ. This divergence gave no efects to the internal reflection spectroscopic measurements except for in the range of the angle of incidence near the critical angle. By using a dye solution which is not adsorbed by glass, the relationship was tested between the reflection absorbance and the optical path of the internal reflection spectroscopy (the effective thickness) which was variable by changing the angle of incidence. The result indicated that the reflection absorbance was proportional to the effective thickness and that the proportional constant was equal to the molar absorption coefficient of the dye solution. This fact shows that the spectrometer made has the expected features. Adsorption of a water-solble porphrin onto glass was investigated in the presence of a cationic surfactant with the spectrometer. The interfnal reflection spectroscopic observation indicated readily as well as in situ that the water-soluble porphrin was adsorbed by the glass-solurion interface. The pH dependence of the adsorption showed that the species adsorbed was the deprotonated form of the porphrin and that electric charges on the glass surface greatly effected the adsorption behavior of the porphrin for the high pH solution. It has been suggested the internal reflection spectrometer made here is useful for the in situ observation of the solid-liquid interface. In addition, the internal reflection spectroscopy has been applied to the study of the liquid-liquid interfac