Once the reactor has shut down, there remains "decay heat" from traces of other radioactive isotopes.

一旦反应堆关闭，它仍热存在有来自其他放射性同位素踪迹的衰变热。

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The control rods are also used to shut the reactor down from 100% power to about 7% power (residual or decay heat).

它也用来关闭反应器，可以从100%的动力降到7%动力（残留的延迟的热量造成）。

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Because the reactor had been shut down a long time ago, the decay heat had decreased to a significantly lower level, so the pressure in the plant stabilized, and venting was no longer required.

因为反应器已经关闭了很长时间，残余热量下降到了一个显著的低水平，因此工厂内部的压力已经稳定，不再需要继续排气。

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Once the reactor has shut down, there remains "decay heat" from traces of other radioactive isotopes.

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If the systems removing the heat from the reactors(even during shut down) fail, you will have a failure of the entire system.

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