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- Keywords sun-screening agent;nitryl hydrogenation;N-alkylation; 防晒剂;硝基加氢;N-烷基化;
- Water contains hydrogen and oxygen. 水含有氢和氧。
- nitryl hydrogenation 硝基加氢
- Water is composed of hydrogen and oxygen. 水由氢和氧组成。
- Water is composed of the elements hydrogen and oxygen. 水是由氢元素和氧元素组成的。
- Water may be resolved into hydrogen and oxygen. 水可以分解为氢和氧。
- The hydrogen is the known the lightest element. 氢是已知的最轻的元素。
- Hydrogen and oxygen combine/Hydrogen combines with oxygen to form water. 氢与氧化合成水。
- A molecule of water consists of two atoms of hydrogen and one atom of oxygen. 水分子含有两个氢原子和一个氧原子。
- Water can be dissolved into hydrogen and oxygen. 水能分解成氢和氧。
- Both hydrogen and oxygen are elements. 氢和氧都是化学元素。
- Hydrogen is a one-valence element. 氢是一价的元素。
- Water is a compound of hydrogen and oxygen. 水是氢和氧的化合物。
- This metal acts on water to set hydrogen free. 这种金属作用于水，就释放了氢气。
- Water can be broken down into hydrogen and oxygen. 水可以分解为氢和氧。
- Water is made up of oxygen and hydrogen. 水是由氢和氧构成的。
- Water is said to consist of oxygen and hydrogen. 据说水由氢气和氧合成。
- He was busy filling out the balloon with hydrogen. 他正忙着给汽球充氢气。
- Hydrogen is by far the lightest of all elements. 氢是所有元素中最轻的。
- Letter "O" stands for oxygen and "H" for hydrogen. 字母“O”代表氧，“H”代表氢。
