Synergy between N and O atom action and substrate surface temperature in a sterilization process using a flowing N2-O2 microwave post discharge

It is demonstrated here that the sterilization process using a flowing N-2-O-2 post discharge reactor involves a specific heating of the bacteria metal holder produced by heterogeneous O and N atoms recombination. Such heating increases with N and O-atom concentrations, which can be varied with the microwave discharge power. It also depends on the metallic material of the holder: a brass support can reach a maximum surface temperature of 120 degrees C while the surface temperature of the stainless steel holder increases to 60-70 degrees C after 40 min of exposure to a N-2-5% 0, post discharge at 0.6 kPa (5 Torr), I L-n, min(-1) and 100 W It is demonstrated that the E. coli destruction efficiency increases with N and O atom density at a constant temperature (60 degrees C) of the stainless steel support and with the support temperature (up to 60 degrees C) at constant N and O atom densities. A cumulative effect was also found with increasing N and O atom density and of the support temperature.