Refractive index measurement of turbid colloidal fluids by transmission near the critical angle
Refractive index measurement of turbid colloidal fluids by transmission near the critical angle
复制标题
通过临界角附近透射测量混浊胶体流体的折射率
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
A. North
中科院分区：
文献类型：
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作者：
G. Meeten;A. North
作者描述了一种改进的阿贝折射仪，用于测量从漫散射混浊样品到棱镜的平面界面上的光学透射率。当棱镜折射率超过样品的折射率时，即使样品含有波长尺寸或更大的颗粒，也存在临界角。因此，可以测量样品折射率。然而，在临界角附近的透射率的测量显示了对某些样品的临界角的差的定义，从而损失了折射率的实验精度。该方法适用于几种聚合物胶乳分散体和一些玻璃球。对于所有的晶格，测得的折射率随胶乳体积分数线性变化。对于所有的分散体，除了一个的折射率的体积分数的依赖关系是在良好的协议与基于Mie散射的球形颗粒的折射率的理论。
The authors describe a modified Abbe refractometer for measuring the optical transmittance across a plane interface from a diffusely scattering turbid sample into a prism. When the prism refractive index exceeds that of the sample, a critical angle is present even when the sample contains particles which are wavelength sized or larger. Hence, the sample refractive index may be measured. However, measurements of transmittance near the critical angle show a poor definition of the critical angle for some samples, with a consequent loss of experimental precision in the refractive index. The method is applied to several polymer latex dispersions and some glass ballotini. For all lattices the measured refractive index varies linearly with latex volume fraction. For all dispersions except one the dependence of refractive index on volume fraction is in good agreement with the theory of refractive index based on Mie scattering by spherical particles.