A waveguide arrangement may include a tank defining a chamber for holding a liquid; and a pulsed waveguide disposed at least partially within the chamber, the PWG comprising: an inner cylinder, the inner cylinder being grounded. % diclofenac or a salt thereof, 0. The support member is connected to and supported by the container means. The method further includes electrochemically depositing a second copper layer on the copper seed layer. In this way, the apparatus can eliminate the system misjudgement problem caused by occurred voltage level errors in the stable state.