https://doi.org/10.1140/epjst/e2016-60217-y
Regular Article
Photochemical migration of liquid column in a glass tube
1 Department of Mechanical Engineering, Tokyo University of Science, 125-8585 Tokyo, Japan
2 Department of Industrial Chemistry, Tokyo University of Science, 162-8601 Tokyo, Japan
a e-mail: mot@rs.tus.ac.jp
Received: 8 July 2016
Revised: 26 September 2016
Published online: 2 May 2017
A light-induced migration of liquid columns in a 2.5-mm glass capillary by photochemical isomerization was demonstrated. The isomerization of a surfactant AZTMA, which was added into ultrapure water, occurred by irradiating UV or visible light and results in the surface tension of the liquid. By utilizing this effect, the column manipulation was performed by irradiating the UV light to a half portion of the liquid column so that liquid-gas interface at two column ends had different surface tension dye to the photochemical isomerization. As a result, the migration of the columns generated by a difference in the Laplace pressure at two ends was observed. The columns firstly advanced at constant speeds depending on their lengths and then decelerated by mixing of isomers in the columns. Moreover, it was found that shorter the column length, higher the mobility. This characteristic was explained by the viscous friction, which counteracted the driving force, and the Marangoni convection in the vicinity of the interface.
© EDP Sciences, Springer-Verlag, 2017