  Stable DC atmospheric pressure normal glow discharges in ambient air were
produced between the water surface and the metallic capillary coupled with
influx of helium gas. Multiple independent repeated trials indicated that
vibrational temperature of nitrogen rises from 3200 to 4622 K, and rotational
temperature of nitrogen decreases from 1270 to 570 K as gas flux increasing
from 20 to 80 sccm and discharge current decreasing from 11 to 3 mA.
Furthermore, it was found that the vibrational degree of the nitrogen molecule
has priority to gain energy than the rotational degree of nitrogen molecule in
nonequilibrium helium microplasma.
