| by separating them | 4 | manner |
| from fuel oil | 3 | other |
| more efficiently | 2 | manner |
| nitrogen → be → produced | 11 |
| nitrogen → be → formed | 5 |
| nitrogen → be → developed | 5 |
| nitrogen → be → made | 4 |
| nitrogen → be → generated | 3 |
| negative | neutral | positive |
| 0.145 | 0.712 | 0.144 |
| Raw frequency | 28 |
| Normalized frequency | 0.531 |
| Modifier score | 0.000 |
| Perplexity | 34.281 |