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- hydrogen helium cycle 氢 氦循环
- Atoms of hydrogen are fused to make helium. 氢原子可熔合成氦。
- Hydrogen provided more lift than helium. 氢气的上升性能优于氦气。
- It gets the hydrogen and helium right. 根据结果表示，氢元素和氦元素都比较正常。
- Water contains hydrogen and oxygen. 水含有氢和氧。
- The pedal of a cycle is attached to a crank. 自行车的踏板与曲柄相连。
- Hydrogen might be depleted with some of it turning into helium. 氢可能被耗尽，一部分变为氦。
- It's easier to cycle with the wind behind you. 顺风骑车省力。
- The release of hydrogen and helium from coal universally exists. 煤中普遍存在着氢气氦气的释放。
- A unit of frequency equal to one cycle per second. 赫兹频率的单位，等于每秒一周
- Modern blimp s use helium instead of hydrogen to maintain buoyancy. 现代软式小飞艇,利用氦取代氢来保持浮力。
- The seasons of the year make a cycle. 一年四季构成一个循环。
- Water is composed of hydrogen and oxygen. 水由氢和氧组成。
- The business cycle experienced a sudden down. 商业周期经历了突然的萧条。
- This is the cycle of economic booms and slumps. 这是经济繁荣和经济萧条的周期变化。
- Cycle across America? Sounds a bit dodgy to me. 骑自行车横越美国? 听起来有些冒险。
- The pedals of a cycle are attached to a crank. 自行车的踏板与曲柄相连。
- The pedals of a cycle are attached to the crank. 自行车的踏板与曲柄相连。
- Helium and neon are inert gases. 氦和氖为惰性气体。
- Her latest stunt is riding a motor cycle through a ring of flames. 她的最新特技表演是骑摩托车钻火圈。
