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- Air consists chiefly of nitrogen. 空气主要由氮气组成。
- Nitrogen ultilized 氮肥用量
- Nitrogen forms most of the Earth's air. 地球上空气的大部分成分是氮气。
- The lamp is full of gaseous nitrogen. 灯里充满了气体氮。
- Nitrogen forms about 78% of the earth's atmosphere. 氮约占地球大气的百分之七十八。
- Will you sunder nitrogen from air? 你能从空气中把氮气分离出来吗?
- Nitrogen is the most commonly used gas. 氮气是最常用的气体。
- Sample gas tubes are flushed with nitrogen. 采气管得用氮气吹扫。
- The main reservoir of nitrogen is the atmosphere. 氮的主要蓄存库是大气层。
- What is the percentage of nitrogen in air? 空气中所含的氮的比例是多少?
- Fast neutrons are also captured by nitrogen. 快中子也可以被氮吸收。
- Nitrogen forms four-fifths of the atmosphere. 氮气占空气的五分之四。
- Nitrogen forms about four-fifths of the atmosphere. 氮约佔大气的五分之四。
- What is the content of the crude nitrogen. 污氮的含氧量是多少?
- Is a nitrogen atmosphere needed for hand soldering? 手工焊接需要使用氮气吗?
- Nitrogen Atmosphere in Bearing Steel Ball H, T. 氮基保护气氛中轴承钢球的热处理
- Nitrogen is a gas without colour or smell. 氮是一种无色无臭的气体。
- Nitrogen is an essential food for plants. 氮是植物一种必不可少的养分。
- Used formerly as a name for nitrogen. 氨氮这个名称的以前的用法
- This bacteria can lay down nitrogen. 这是种固氮菌。
