It didn't come as a shock to learn that the fuel and cooling systems are the most common causes of breakdown.

不足为怪的是，燃料和冷却系统是故障的最常见原因。

《柯林斯英汉双解大词典》

When auxiliary batteries were exhausted, the plant was without power to continue cooling reactor cores and spent fuel pools.

一旦辅助电池用尽，核电站将无法继续冷却反应堆内核以及乏燃料池。

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Workers are attempting to remove the radioactive water from the tsunami-ravaged nuclear compound and restart the regular cooling systems for the dangerously hot fuel.

工作人员正试图把有高辐射积水从被海啸破坏的核化合物中分离出来，并且重启常规制冷系统以冷却这些危险的高热燃料。

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Hydrogen is building up because, due to low levels of cooling water, fuel rods are partially exposed, causing them to overheat.

BBC: Japan quake: Nitrogen pumped into nuclear reactor

As many as 15 percent of the 5, 000 previously approved welds in the reactor's auxiliary plumbing, containment dome and spent-fuel cooling systems were X-rayed and found to be defective due to air pockets, poor soldiering and heat damage.

CENTERFORSECURITYPOLICY: A Chernobyl reminder just off our shores

It seems too impossible to believe, but according to reports from CNN, Reuters and the AP tonight, the last workers at the Fukushima-Daiichi reactors have been withdrawn from the scene, halting efforts to continue cooling partially melted fuel rods with ocean water.

FORBES: Reports: Nuke Workers Abandon Japan's Melting Reactors