高透明液体透射率的测定

Measurement of transmittance for highly transparent liquid

分析了通常利用可见分光光度计测定高度透明液体透射率易得出错误结果的原因。通过对错误结果的分析,提出了两种简单易行的测定高透明液体透射率的方法。一种方法是将比色皿的两个透明面紧密贴在一起,中间加有待测液体形成的液膜,形成"液膜参比池"。另一种方法是将长为1cm的比色皿中装入待测样品作为参比池,而将长为2cm的比色皿中装有待测样品进行测定。根据这两种方法,对多种常见液体进行了测定。结果显示,两种方法的测定结果基本相同,常见液体如乙醇、水等在可见光波长范围内的透射率均为98%～100%。这两种方法解决了高透明液体透射率测定易出现错误的问题,为人们比较和选取高透明液体提供了两种可行的方法。

This paper analyzes the reasons that the mistaken transmittance results are prone to occur in a highly transparent liquid measurement by employing a visible spectrophotometer in traditional meth- ods. On the basis of the analysis results, two kinds of simple ways for measuring the transmittance of highly transparent liquid are proposed. One way is to fit both kinds of transparent faces of a colorimet- ric ware closely together, in which the film is formed with the pending liquid to be tested. This struc- ture is known as the ＂liquid film reference cell. The other way is to fit the pending liquid into a 1 cm length colorimetric ware as the reference cell, and fill the pending liquid into a 2 cm length colorimet-rie ware as the sample cell. With the two methods, several kinds of common liquids are measured and almost identical results are obtained. Measurements show that the transmittances of measured liquids such as alcohol, water are all in 98%~100% at the visible light range. These ways eliminate the mis- taken transmittance results and provide effective methods for the measurement of transparent liquid.