Figure 1. Non-thermal atmospheric pressure plasma (NTP) generating system used in this study (A) Photograph of our spray-type plasma generating system.
(B) Optical emission spectra of the He and O2 gas mixture plasma according to the electric intensity (2 or 4 kV) in the range of 280–920 nm. (C) Image of the “torch with spray-type” plasma jet with He and O2. The visible plasma had a length of approximately 2.5 cm that varied with the gas flow and voltage.
