Figure 1
Phys. Rev. E 82, 066307 (2010)

Better plumes through chemistry. A smoke-ring flow pattern–or vortex ring–can develop, pinch-off, and be regenerated, all without external forces, when the flow is driven by chemical reactions. The left-most frame shows the reaction in water, while the middle and right show it with 20 and 30 percent glycerol, respectively. Such complex flows are possible when chemistry drives fluid motion. (See video below.)