There is a minimum size for the reactor at which the chain reaction will just work.
为使链式反应刚好能够维持下去，反应堆要有一个最起码的尺寸。（目的状语）
Part of the extension may also be related to the size of the reactor compartment.
加长的一部分可能还与反应堆舱的尺寸有关。
Part of the extension may also be related to the size of the reactor compartment.
加长的一部分可能还与反应堆舱的尺寸有关。
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