一种新的表面张力测定方法——真球气泡法

A new method for measuring surface tension--real sphere bubble method

设计了一个新的表面张力测定装置,通过实时测定液膜气泡的半径及其内外压差来获得被测液体的表面张力.该测定液体表面张力的方法简称为真球气泡法(real sphere bubble method,RSBM).对十二烷基硫酸钠(sodium dodecyl sulfate,SDS)溶液的表面张力进行了测定,结果与文献值吻合,且测定装置的绝对精度为98.2%.通过检测到的液膜气泡突然长大所需要的最大压差值△Pm及其表面积随时间的变化过程,定量分析了△Pm与溶液起泡难易程度及气泡大小的关系.

A new device for measuring surface tension was designed,and the surface tension of liquid was calculated through real-time measurement of the radius and the differential pressure between inside and outside of the liquid bubble.This new method of measuring liquid surface tension is known as real sphere bubble method(RSBM).In this paper,the surface tension of sodium dodecyl sulfate(SDS)solutions is measured.The results are consistent with the literature.The absolute accuracy of this apparatus is 98.2%.In addition,△Pm is the maximum differential pressure required for rapid growth of bubbles formed by SDS solutions.The difficult level of foaming a liquid bubble and the size of a bubble is quantitatively analyzed by detecting△Pm for sudden bubble growth and the change of surface area over time.