| Share | Phrase |
|---|
| 23.63% | enriched [physical/chemical] mixture |
| 22.53% | enriched [physical/chemical] zone |
| 15.55% | enriched [physical/chemical] air |
| 5.32% | enriched [physical/chemical] input |
| 5.21% | enriched [physical/chemical] fuel |
| 4.75% | enriched [physical/chemical] combustion |
| 3.29% | enriched [physical/chemical] ratio |
| 3.04% | enriched [physical/chemical] gas |
| 2.97% | enriched [physical/chemical] source |
| 2.30% | enriched [physical/chemical] range |
| 2.12% | enriched [physical/chemical] charge |
| 1.88% | enriched [physical/chemical] fer |
| 1.79% | enriched [physical/chemical] flow |
| 1.54% | enriched [physical/chemical] mode |
| 1.40% | enriched [physical/chemical] communication |
| 1.40% | enriched [physical/chemical] condition |
| 1.19% | enriched [physical/chemical] value |