oxygen demand的用法和样例：
例句
- The exercises which occur without oxygen are called anaerobic.
运动中不需要氧的就是无氧运动。 - An animal is dependent on the oxygen which he inhales for his life.
动物离不开氧气，为了生存需要吸氧。 - The results showed that magnesium hydroxide had good effect for decoloring and suspended substance removal,meanwhile,removal rate of chemical oxygen demand was also quite high.
研究结果表明，氢氧化镁在印染废水的处理过程中，具有良好的脱色效果和悬浮物的去除效果，对化学需氧量的去除率也相当高。
