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Surface tension gradient around an alcohol droplet moving spontaneously on a water surface
Shogo Oshima1, Tomonori Nomoto, Taro Toyota
1Department of Applied Chemistry and Biotechnology, Chiba University.
Abstract:
The surface tension gradients in the front and rear sides of a 1-hexanol droplet exhibiting self-propelled motion were compared by a time-resolved quasi-elastic laser scattering method. The velocity of the alcohol droplet strongly correlated to the difference of the inverse of the recovery distances of the surface tensions between the front and rear sides. This result indicates that the spontaneous alcohol droplet motion is governed by an imbalance in the Marangoni convection flow, induced by an asymmetric surface tension distribution.
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