Identification of Peak near 200 nm in Absorbance Spectrum of Distilled Water upon Atmospheric-Pressure Plasma Jet Irradiation

摘要

An argon atmospheric-pressure plasma jet was directly irradiated onto distilled water.As a result, a peak appeared at approximately 200 nm in the absorbance spectrum of the distilled water, and the peak intensity increased with plasma jet irradiation time.In the distilled water sample, the electrical conductivity increased and the pH decreased with increasing irradiation time.A comparison of the absorbance spectrum of the distilled water sample with that of nitrate ions (NO_(3)~(-)) in a sodium nitrate (NaNO_(3)) aqueous solution indicated that the peak near 200 nm was due to NO_(3)~(-).This finding was also supported by the result of a capillary electrophoresis (CE) measurement.