A Modified Calibration Technique for Pendant Drop/Bubble Tensiometry
Other Title
懸垂液滴張力儀校正技術之改良
Journal
Journal of the Chinese Institute of Chemical Engineers
Journal Volume
32
Journal Issue
2
Start Page
109
End Page
116
ISSN
0368-1653
Date Issued
2001-03
Author(s)
Abstract
懸垂液滴張力法為一種藉由液滴（或氣泡）之形狀來決定張力值的方法，可廣泛的應用於表面張力與界面張力的測量。文獻中指出此法測得的表面張力與液滴（或氣泡）的體積有關（Langmuir 11, 4159, 1995）。本研究針對垂直與水平像素比例（ar及水平像素尺寸（lx）對於表面張力計算的影響作系統性的探討。同時提出一個兩階段的調整步驟分別校正垂直與水平像素比例（ar）以及水平像素尺寸（lx），以期消弭表面張力與液滴（或氣泡）體積的相關性。經由測量水、次乙基乙二醇、正十六烷以及正辛烷的表面張力的實驗結果可以得知，此一兩階段的調整步驟確實可以使表面張力與液滴（或氣泡）體積的關連性消除。
The pendant drop/bubble method is widely used to measure the surface tension for various shapes of liquid drops or air bubbles. It was found previously (Langmuir 11, 4159, 1995) that the surface tension is bubble (drop)-size dependent. In this study, the effects of the aspect ratio (ar) and the horizontal dimension of a pixel (lx) on calculation of the surface tension were systematically examined. A two-step procedure for tuning ar and lx is proposed to eliminate the bubble (drop)-size dependence of the surface tension. Four liquids, water, ethylene glycol, n-hexadecane, and n-octane, were used to test this procedure, and excellent results were obtained. Essentially, the bubble (drop)-size dependence of the surface tension vanishes after the two-step tuning procedure is applied.
Subjects
Pendant Drop Method
Surface Tension
Capillary Constant
Bubble Volume
Aspect Ratio
Type
journal article