During that period it became clear that a partial meltdown had taken place in at least one of the six reactors.

在此期间才清楚，六个反应堆里至少有一个发生了部分的熔毁现象。

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However, so far it seems more likely to resemble the Three Mile Island (TMI) accident in Pennsylvania in 1979 which, like Fukushima, lost coolant and had a partial meltdown.

但是，目前为止和福岛核事故最相像的是1979年发生在美国宾夕法尼亚州的三里岛事故，那次事故也是冷却出现了问题导致了核反应堆差点儿融化。

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The Unit 2 reactor has been shut down since a partial meltdown in 1979.

CNN: Pump triggers Three Mile Island reactor shutdown, NRC says

The partial meltdown in bank stocks yesterday was a surprise and a warning.

FORBES: Banks Are To Be Made Too Big To Not Fail--Maybe

The Japanese government said Monday that the fuel rods in one reactor have fused together in a partial meltdown.

WSJ: Uranium Firms Take Hit After Earthquake