FIG. 3.
The mechanism of the siphoning-evacuation approach. (a) The reaction chamber was filled with liquid at ωH. (b) By reducing the rotational speed to ωL, the liquid primed the siphoning channel by the capillary action and stopped at the exit of the siphoning channel. (c) In path 1, by increasing the rotational speed to ωH (ωH < ωC), the liquid from the reaction chamber was drained into the waste chamber while the siphoning channel was filled with liquid. (d) The newly added liquid would be drained from the reaction chamber into the waste chamber immediately. (e) In path 2, by increasing the rotational speed to ωH (ωH > ωC), the liquid was drained from the reaction chamber into the waste chamber and the siphoning channel was filled with air. (f) When the liquid was added to the reaction chamber at ωH, it stayed in the reaction chamber.