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- Cell walls, cell membranes and nucleus envelopes of some cells were lethally injured after liquid nitrogen preservation, which might account for the death of some cells. 在液氮中保存后，有一部分细胞的细胞壁、质膜以及核膜均有不可逆的损伤，可能是部分细胞致死的原因之一；
- Air consists chiefly of nitrogen. 空气主要由氮气组成。
- The aim of the policy is the preservation of peace. 这一政策旨在维护和平。
- 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。
- The paintings were in an excellent state of preservation. 这些画保存的非常好。
- fill nitrogen preservation 充氮保藏法
- Plagiarists, at least, have the merit of preservation. 抄袭者，起码也有保存文物的功劳。
- The environmentalist launched out at great length on energy preservation. 这位环境保护论者就节约能源问题发了一通议论。
- Liquid nitrogen preservation 液氮保藏
- The old building is in good preservation. 那座老式大楼保存完好。
- nitrogen preservation 充氮保藏
- 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。
- Food, water and air are essential to life/for the preservation of life. 食物、水和空气对(维持)生命是必不可少的。
- Sample gas tubes are flushed with nitrogen. 采气管得用氮气吹扫。
- Self- preservation is the first law of nature. 自我保护，天经地义。
- 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?
