A process for applying a graphite coating to the interior of a prismatic battery can by filling the can with a slurry containing graphite particles, immediately removing the slurry with an aspirating nozzle and then drying the residue left in the battery can to leave a thin film of graphite on the interior of the can. Another aspect of the invention relates to a pharmaceutical composition, comprising a compound of the present invention or a pharmaceutically acceptable salt thereof; and a pharmaceutically acceptable excipient. Phase andor frequency characteristics of one or more of the signals are controlled to provide the desired phase, frequency, andor amplitude characteristics of the desired time-varying complex envelope signal.