Abstract
The distribution of electron temperature T(e) and density N(e) for direct current glow plasma discharge was investigated, using a single Langmuir probe, inserted inside the plasma cell. The radial temperature distribution has the same values, except with a small increment variation at the cathode edge, and an axial decrement for the temperature T(e) distribution profiles from the cathode fall region, passing the abnormal glow region, up to the faraway axial region. The radial distribution of the electron density N(e) has its highest value at the cathode, with very intense plasma at the cathode fall region, and more N(e) decrement in the abnormal glow region, passing the abnormal glow region up to the faraway axial region. In the axial N(e) distribution, an increase in N(e) from the cathode fall region reaches maximum values in the abnormal glow region and decreases in the faraway axial region. The optimal plasma surface treatment of non-woven silk fabric (n-WSF) can be achieved by utilizing a high plasma density and low energy of electrons to inactivate viable cells attached to (n-WSF) at very short application times, leading to complete inactivation, where the bacterial inactivation rate increases in the abnormal glow region. Based on analyses of the experimental data of initial and final densities of viable cells using survival curves in the abnormal glow discharge region, a dramatic inhibitory effect of plasma discharge on the residual survival microbe ratio was observed.