From the beginning, the cloud hanging over the whole hydrogen enterprise has not been the power source as such, but the intractable difficulty of distributing and storing the stuff.

从一开始，盘旋在氢能源开发企业头上的阴云已经不是像这样的动力来源的问题，而是那些棘手的配送和储存原料的难题。

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The technique worksbecause when water evaporates at sea, a combination of hydrogen and oxygenisotopes rise to form a cloud, which then releases rain when it moves inland.

这项技术的确有效，因为当水从海中蒸发后，氢和氧的同位素升起形成云，接着当它飘至陆地上空时再变为雨。

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Molecular hydrogen (H2) radiated the heat out of the clouds, so we need to know how much H2 was in the cloud.

氢分子(H2)在初生云周围散射热量，因此我们要知道在初生云中氢分子的数量。

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One shows the remains of a dying star four thousand light years away which has thrown off a cloud of glowing hydrogen gas.

VOA: special.2009.09.30

One of LRO's instruments, the Lyman Alpha Mapping Project (Lamp), detected enhanced concentrations of mercury and atomic hydrogen in the cloud from the demise of the twin spacecraft.

BBC: Nasa reveals new information about moon probes crash sites

From the beginning, the cloud hanging over the whole hydrogen enterprise has not been the power source as such, but the intractable difficulty of distributing and storing the stuff.

ECONOMIST: Tech.view: Hydrogen tries again | The