| Samples | Oxidation peaks (V) | Reduction peaks (V) | Difference value (V) |
| NCM-a |
|
|
|
| 1st | 4.2005 | 3.5504 | 0.6501 |
| 2nd | 3.9868 | 3.5514 | 0.4354 |
| 3rd | 3.9714 | 3.5549 | 0.4165 |
| NCM-b |
|
|
|
| 1st | 4.1013 | 3.6045 | 0.4968 |
| 2nd | 3.9218 | 3.6199 | 0.3019 |
| 3rd | 3.8951 | 3.6278 | 0.2673 |
| NCM-c |
|
|
|
| 1st | 4.1218 | 3.6024 | 0.5194 |