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- Helium nitrogen oxygen saturation diving 氦氮氧饱和潜水
- carbon oxygen ratio spectra logging 碳氧比能谱测井
- Water contains hydrogen and oxygen. 水含有氢和氧。
- Air consists chiefly of nitrogen. 空气主要由氮气组成。
- Unlike oxygen, the element nitrogen is inactive. 与氧不同，元素氮不活泼。
- Oxygen enters into many compound bodies. 氧是许多化合物的组成部分。
- 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。
- Mars is too dry and poor in oxygen. 火星上面过于干燥，并且缺乏氧气。
- Water is composed of hydrogen and oxygen. 水由氢和氧组成。
- Fish take in oxygen through their gills. 鱼通过鳃摄取氧气。
- The ratio of students to teachers is 35:1. 学生和老师的比率是三十五比一。
- The ratio of schoolboys to schoolgirls is 2 to 1. 男学生和女学生的比例是2比1。
- If it were not for oxygen and nitrogen in the air, no man could live on the earth. 大气中如果没有氧和氮，人就无法生存于地球了。
- Men outnumber women here in the ratio of three to one. 此地男子数量以三比一超过女子。
- One atom of oxygen is linked to the nitrogen atom by a double bond. 一个氧原子以双键与氮原子相连。
- The first or last term of a ratio or a series. 首项，末项比率或数列中第一个或最后一个项
- The oxygen react vigorously with the impurity in the iron. 氧气与铁中的杂质发生剧烈的化学反应。
- 700 kPa nitrogen oxygen mixture pressure reduced rat EEG frequency significantly. High partial pressure oxygen may take an antagonistic effect on nitrogen narcosis. 0kPa氮氧混合气中 ,即氮分压达到 6 78kPa时可对大鼠脑电活动产生较明显影响。
