nitrogen
US /ˈnaɪ.trə.dʒən/
UK /ˈnaɪ.trə.dʒən/
名词
氮
the chemical element of atomic number 7, a colourless, odourless unreactive gas that forms about 78 per cent of the earth's atmosphere. Liquid nitrogen (made by distilling liquid air) boils at 77.4 kelvins (−195.8°C) and is used as a coolant.