NONUNIFORM PULSE DISCHARGE-INDUCED RADICAL PRODUCTION IN DISTILLED WATER

A spark discharge in water or in an aqueous solution can produce ultra violet radiation and active species (radicals). In this paper, the cha racteristics of the spark discharge is investigated to identify the me chanism for the formation of radicals by the pulsed discharge. The spa rk discharge breakdown time and radical formation were studied using a needle-plate electrode system. The ultraviolet radiation and active s pecies formation were studied for both the pulsed streamer corona disc harge and the spark discharge. The distribution of OH radicals in spac e and time were investigated using emission spectroscopic analysis. Th e results showed that active species (. OH, . H, . O, H2O2) existed in the spark discharge, and that the hydroxyl radical (OH) was formed ma inly within the discharge channel. In addition, the emission intensity of OH radical was higher in the case of the spark discharge than in t he streamer corona discharge. (C) 1998 Elsevier Science B.V. All right s reserved.