At normal conditions you're not expecting the reactor vessel to fail because it's warm and hot but if you hit it with cold water it's a problem.

在正常的情况下，你不会期待，反应堆管道失效，因为它是暖和和热的，但是，如果用冷水你冲击它，那是一个问题。

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We notice that the differences are that the water in the reactor vessel is not allowed to boil.

我们注意到不同就在于，在反应堆管道的水是不允许油的。

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Some of the salt might be settling to the bottom of the reactor vessel rather than sticking to the fuel rods.

部分盐也许会沉入反应堆容器的底部，而不会粘在燃料棒上。

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In that accident, the lack of a containment vessel surrounding the reactor meant radioactive materials from the accident were spread far and wide.

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Integral reactor systems -- including the reactor vessel itself, six steam generators, five primary coolant pumps, 12 isolation valves and more -- were stored outside for up to 18 months, exposed to highly corrosive tropical sea air and weather.

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Tuesday's explosion at the No. 2 reactor in the Fukushima complex, 150 miles north of Tokyo, for the first time raised the possibility that the key containment structure of the unit, which protects the reactor vessel and keeps dangerous radioactive materials from leaking out, had been damaged.

WSJ: Japan's Nuclear Crisis Escalates