Bacteria Inactivation Using DBD Plasma Jet in Atmospheric Pressure Argon

<正> A coaxial dielectric barrier discharge plasma jet was designed.which can be operatedin atmospheric pressure argon under an intermediate frequency sinusoidal resonant power supply,and an atmospheric pressure glow-like discharge was achieved.Two kinds of typical bacteria,i.e.,the Staphylococcus aureus(S.aureus)and Escherichia coil(E.coil).were employed to studythe bacterial inactivation mechanism by means of the non-thermal plasma.The killing log value(KLV)of S.aureus reached up to 5.38 with a treatment time of 90 s and that of E.coil up to 5.36with 60 s,respectively.According to the argon emission spectra of the plasma jet and the scanningelectron microscope(SEM)images of the two bacteria before and after the plasma treatment,itis concluded that the reactive species in the argon plasma played a major role in the bacterialinactivation.while the heat,electric field and UV photons had little effect.