Self-Pinning on a Liquid Surface

Abstract

We report on the first experimental evidence of a self-pinning liquid drop on a liquid surface. This particular regime is observed for a miscible heavier oil drop (dichloromethane) deposited on an aqueous solution laden by an ionic surfactant (hexadecyltrimethylammonium bromide). Experimental characterization of the drop shape evolution coupled to particle image velocimetry points to the correlation between the drop profile and the accompanying flow field. A simple model shows that the observed pinned stage is the result of a subtle competition between oil dissolution and surfactant adsorption.

Complexity and bifurcations in the motion of a self-propelled rectangle confined in a circular water chamber

“…Fast rotation around the center was also observed for soft objects. 48,49 For a pointed ellipse, the transition between polygonal motion and rotation along the dish wall was recorded. A polygonal motion was dominating for a rhomboid, but due to object asymmetry, it also included object rotation.…”

Periodic Motion in the Chaotic Phase of an Unstirred Ferroin-Catalyzed Belousov Zhabotinsky Reaction

“…Even though their origin is different, they show a surprisingly similar shape to the ones seen in a BZ reaction. When only one little drop of dichloromethane is added to a CTAB solution, it is possible to observe highly organized patterns, such as oscillations of the drop diameter (Antoine et al, 2016;Wodlei et al, 2018). As in the BZ reaction, convection plays a crucial role in this system too.…”