nitrogen source的用法和樣例：
例句
- Peptone, a semidigested protein, is primarily a nitrogen source.
屬於半分解蛋白質的蛋白凍基本上是一種氮源。 - This study is about carbon and nitrogen nutrient sources utilization.
摘要通過試驗探討茶樹菇對碳源和氮源的利用。 - Therefore the EOM, especially non-hycrocarbons and asphaltene, could be considered as the most important source materials of BTZG in East Depression of the Liaohe basin.
因此認為可溶有機質，尤其是其中的非烴和瀝青質是東部凹陷過渡帶氣最主要的母源物質。
