quality concentration的用法和樣例：
例句
- The difference between par-ticle mass concentration and Bosch smoke number is indicated.
指出微粒的質量濃度與波許煙度的不同。 - The alkalescent condition reduces the mass concentration of iron ions and fastens the nitration reaction of ammonia nitrogen, and leads to the concentration of nitrate.
偏鹼性條件使鐵離子質量濃度降低，同時促進了氨氮硝化反應進行，使礦井水中硝酸鹽和亞硝酸鹽質量濃度增加。
