Marangoni instability from picolitre sessile droplets —Lisong Yang, Jack Goodall & Colin Bain, Durham University

What if a picolitre ethanol drop hits a thin water film of a few microns? High speed camera caught the moment of drop impact: water film is contracted into a drop and repelled, whereas ethanol drop spreads with the development of the fingering instability at the nearside of water droplet.

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