Liquid metal imbalance of the surface tension induces a pressure difference between the rear and the head, which produces a thrust to drive the droplet toward the head; at the same time, the hydrogen produced in the electrochemical reaction process also further raises the thrust. The discovery of this phenomenon laid the technical foundation for the development of intelligent motors, vascular robots, fluid pumping systems, flexible actuators and even more complex liquid metal robots. Liquid metal Liquid metal consists of alloys with very low melting points which form a eutectic that is liquid at room temperature. The standard metal used to be
Common external power supply either "captive" (permanently attached to the power supply) or detachable. If detachable, the cable must connect to the power supply via a standard USB type-A plug. The MoU which defines the common external power supply as well as the related EC standardisation mandate both allow for the use of the common external power supply also with phones not equipped with a micro-USB receptacle. "... [MoU] 4.2.1 ... if a manufacturer makes available an Adaptor from the Micro-USB connector of a Common EPS to a specific non-Micro-USB socket in the Mobile Phone, it shall constitute compliance to this article" and, "...