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Movies of interfacial phenomena and pattern formation
In an aqueous phase containing surfactant that can adhere to a glass surface, an oil droplet that contains chemicals that pair with the surfactant moves spontaneously on a glass surface. We have found that the motion of an oil droplet becomes regular when that is placed in an appropriate boundary condition, whereas in an isotropic condition, an oil droplet moves irregularly.
The thin film of water-ethanol mixture spontaneously climbs up the glass surface when the ethanol evaporates from the film. Since the evaporation of ethanol is slower near the bulk of the mixture, there occurs a gradient of ethanol concentration on the film. Ethanol is surface surface-active chemical; therefore, the surface tension of the mixture is higher at the top of the film. This unbalanced surface tension results in the Marangoni flow. Finally, the liquid is spontaneously absorbed into the higher glass surface, and by the effect of gravity, the mixture forms a droplet on the glass surface.
Placing an oil droplet with fatty acid on an aqueous phase with a cationic surfactant, the oil droplet spontaneously deforms its interface in the absence of any biological components. Accompanied by the spontaneous deformation, surfactant aggregation is formed in the aqueous phase close to the oil-water interface. This aggregate is elastic and compresses the oil droplet. As a result, the droplet behaves as if it were an artificial amoeba.
A famous chemical reaction that shows a temporal pattern, i.e., oscillation, as well as a spatial pattern, i.e., target and spiral patterns.
You can see the simplest type of self-propelled object driven by Marangoni flow (detergent boat). You can also see the Benard convection.