Enhorning G
J Appl Physiol Respir Environ Exerc Physiol. 1977 Aug;43(2):198-203. doi: 10.1152/jappl.1977.43.2.198.
Surface tension is determined with an apparatus which records pressure across the surface of a bubble, expanded in the sample liquid and communicating with ambient air. The disposable sample chamber, with a volume of 20 microliter, communicates with a pulsator and a pressure transducer. The volume displacement of the pulsator's moving piston is hydraulically geared down 1,000 times, which gives the pulsator a stroke volume of 0.43 microliter. When this volume is moving into the sample chamber, it causes the bubble radius to change from a maximum of 0.55 mm, accurately measured through a microscope, to a minimum of 0.4 mm. The pulsator speed is usually 20 rpm, but it can be changed from 0.02 to 80 rpm. From the known pressure gradient across bubble surface, and bubble radius, surface tension is calculated with the law of Laplace.
表面张力是用一种仪器测定的，该仪器记录在样品液体中膨胀并与周围空气相通的气泡表面的压力。一次性样品室的体积为20微升，与脉动器和压力传感器相通。脉动器移动活塞的体积位移通过液压装置降低了1000倍，这使得脉动器的冲程体积为0.43微升。当这个体积进入样品室时，会导致气泡半径从通过显微镜精确测量的最大0.55毫米变化到最小0.4毫米。脉动器速度通常为20转/分钟，但可以在0.02至80转/分钟之间变化。根据气泡表面已知的压力梯度和气泡半径，利用拉普拉斯定律计算表面张力。
