Sodium has a role of circulating fluid outside the cell .

钠在细胞外起着循环流体的作用。

This will allow for continuous cooling of water circulating through the reactor .

这将会使反应堆内循环的水能够不断被冷却。

Winds and tides have long been known to drive currents circulating within the ocean .

长期以来，人们已经知道风和潮汐推动着洋流在海洋中不断循环。

Circulating tumor cells are extremely rare , 1 to 100 per milliliter of blood .

循环肿瘤细胞极为稀少，每毫升血液中的个数为1至100个。

If the crusts are thick enough , they can block water from circulating between the fuel rods .

如果这些外壳足够硬，那么它们就能阻止水在燃料棒之间的循环。