Measurement of Dynamic Interfacial Properties in an Overflowing Cylinder by Ellipsometry

✍ Scribed by Samantha Manning-Benson; Colin D. Bain; Richard C. Darton

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 191 KB
• Volume: 189
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1997.4797

✦ Synopsis

The complex interplay between hydrodynamic flow, mass Ellipsometry has been used to analyze the surface of aqueous transport, and the surface properties of the surfactant makes solutions of hexadecyltrimethylammonium bromide in an overit essential to study model systems in which the variables flowing cylinder. The factors affecting the precision and accuracy are well defined and the hydrodynamic and chemical properof the ellipsometric measurements are discussed and ellipsometry ties of the system can be measured. One well-established is compared with surface tensiometry as a method for studying technique for studying nonequilibrium surfaces under dynamic interfacial properties. The coefficient of ellipticity was steady-state conditions is the overflowing cylinder (OFC)

found to vary quadratically with radial distance from the center (3). In an OFC, the liquid is pumped vertically upward of the cylinder, in agreement with models proposed in earlier literthrough a cylinder and allowed to flow over the horizontal ature. The dynamic surface tension inferred from noninvasive ellipsometric measurements is much higher than previously reported rim. The surface is static at the center of the cylinder (the measurements of the dynamic surface tension obtained with a stagnation point) and accelerates radially outward toward the Wilhelmy cylinder. ᭧ 1997 Academic Press rim. Large surface expansion rates are possible, producing a Key Words: overflowing cylinder; CTAB; ellipsometry; surface surface far from equilibrium. In the presence of a surfactant, tension.

a radial surface tension gradient arises, which greatly increases the surface velocity. Since the 1950s, overflowing cylinders and overflowing funnels have been exploited in