摘要 |
A method, and apparatus, wherein an effect of establishing electrodes in a region of a liquid is achieved by providing a core of magnetically-conductive material around a lateral wall containing the region of the liquid, the core of magnetically conductive material passing through a primary coil energised by an electrical signal, and wherein respective parts of the region of the liquid on opposite sides of the magnetically conductive core are connected by a passage containing the liquid, the passage and liquid affording a selected electrical resistance. |