What a pebble bed reactor is, is in fact the same coated particle with the uranium kernel and there are about ten thousand of these particles that are put into a graphite pebble.

什么是卵石层反应堆，事实上就是同样的,铀核包装的微粒,有大约1万的微粒,被放入了一个石墨卵石里。

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There was a moment when there existed the danger of a nuclear explosion, and they had to get the water out from under the reactor, so that a mixture of uranium and graphite wouldn't get into it with the water they would have formed a critical mass.

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