Samples with plasma treatment | ||
| BP11 | Ar + N2 | (BP + PL + Z) |
| BP16 | Ar + H2O | (BP + PL + Z) |
| BP7 | Ar + O2 | (BP + PL + Z) |
| TC6 | Ar | (TC + PL) |
| TC9 | Ar + O2 | (TC + PL) |
| Z12 | Ar + N2 | (Z + PL + TC) |