Hydrogen in the steam is believed to have mixed with oxygen, causing the two explosions.

据信，蒸汽中的氢气混合了氧气，导致了这两次爆炸。

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The venting process triggered the explosion when combustible hydrogen released by the steam mixed with oxygen in the air, officials said.

日本官员说，正是被释放的蒸汽包含的可燃氢气在接触到大气中的氧气后，导致了那次爆炸。

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The control rods, in turn, react to the superheated steam and begin to release hydrogen and radioactive gases. These are also released through the PORV.

控制棒接连与过热蒸汽产生反应，释放出氢气以及放射性气体，这些气体也通过减压阀释放。

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Engineuity, a company started by Amnon Yogev, has reportedly developed a method for vehicles to "produce their own fuel" using metals such as magnesium and aluminum to create hydrogen and steam.

ENGADGET: Engineuity developing hydrogen-creating, emission free vehicle

"Economics dictates that 95% of current U.S. hydrogen is produced by steam-methane re-forming of non-renewable natural gas, " Michael K. Heiman, professor of environmental studies at Dickinson College, wrote in a study of the proposed hydrogen economy last year.

FORBES: Magazine Article

Hydrogen is conventionally produced by steam reforming natural gas, a process that wastes some of the energy stored in the gas while releasing large amounts of CO2.

FORBES: Could Hydrogen Breakthrough Revive The Fuel-Cell Car?