Investigations were carried out to clear the superposition effects of the silent discharge, the surface discharge and the discharge luminescence on ozone synthesis. A coaxial and cylindrical double layer discharge tube was used for ozone synthesis. The inner tube was made of quartz and the outer tube of hard glass. Outer and inner tubes were rolled by aluminum foil and nickel wire coil respectively, as electrodes, and a rod electrode was inserted at the center of the inner tube. Nitrogen gas filled the inner tube and oxygen flowed between the inner and the outer tubes. Silent discharges were generated in oxygen gas, and nitrogen discharges in the inner tube with surface discharge on its surface. The following results were obtained. Amounts of ozone generated by silent discharges and surface discharges were almost the same. The sum of the amounts of ozone generated by the silent discharge alone and by the surface discharge alone is approximately equivalent to the amount of ozone generated when both types of discharge occurred simultaneously in oxygen gas. The superposition effect of silent discharge and luminescence of nitrogen discharge was studied, but no remarkable effect was observed.
