Microparticles forming a network of chains at the interface of a bubble. The microstructures formed by colloids at fluid interfaces are usually due to electrostatics and capillarity. This unique pattern was obtained by deforming a bubble decorated with colloidal particles with ultrasonic waves, resulting in complex interactions between the particles.
Marble chains on a bubble —

Microparticles forming a network of chains at the interface of a bubble. The microstructures formed by colloids at fluid interfaces are usually due to electrostatics and capillarity. This unique pattern was obtained by deforming a bubble decorated with colloidal particles with ultrasonic waves, resulting in complex interactions between the particles.

https://fluids.ac.uk/files/07_Photo_180331.1522825646.png