Search results: black hole

The coffee-ring effect

The coffee-ring effect

MaterialsPhysics

By Mireia Altimira

Have you ever observed how a drop of coffee dries? As water evaporates, its suspended particles are deposited in a ring-like fashion in a phenomenon known as the coffee-ring effect. Obviously, this effect is undesirable in the numerous practical applications that require a uniform coating. However, the way to avoid it has remained unknown. The […]