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- Air consists chiefly of nitrogen. 空气主要由氮气组成。
- Nitrogen forms most of the Earth's air. 地球上空气的大部分成分是氮气。
- This layer of rock contains a lot of flint. 这一岩层中有大量燧石。
- 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。
- The inner layer of the wall of a spore. 孢子内壁孢子壁的内层
- There is a fine layer of dust on the desk. 桌子上有一层薄薄的尘土。
- The middle, usually fleshy layer of a fruit wall. 中果皮果皮中间通常含肉较多的那一层
- The bottom layer is a mixture of sand and clay. 最下面的一层是沙和泥的混合物。
- A fine layer of dust covers everything. 所有的东西都盖了一层薄薄的灰尘。
- This layer is rich in dissolved nitrogen and nitrides. 它能有效的分解氮和氮化物。
- A layer, as of doubled-over cloth or of paperboard. 一层一层，如折叠过的布料或纸板的
- A surface, layer, or mass of frozen water. 冰面冻结的水的面、层或块
- A thin layer of bone, membrane, or other tissue. 骨骼、粘膜或其它组织的薄层
- Will you sunder nitrogen from air? 你能从空气中把氮气分离出来吗?
- A thin, flat layer or scale, as that of a fish. 外表组织薄而平的一层或鳞状物，如鱼鳞
- 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?
