Fig. 4From: Modulation of nanoparticle separation by initial contact angle in coffee ring effectImage of the droplet with same contact angle but different volumes a θ1 = 50°, b θ2 = 30°, c θ3 = 14°. d Separated length between 100 nm and 1 µm beads in the evaporated droplet with same contact angle but different volumesBack to article page