If anything unusual occurs, the control rods immediately drop, shutting off the nuclear reaction.

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The control rods caused each generation of fission to produce fewer neutrons and fewer fission reactions.

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Eugene Kurz, 41, from Toronto, cut his finger while playing, pinching it as he pushed one of his metal control rods.

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With no control rods to jam, they are far safer than the old models -- you might well call them nuclear batteries.

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They executed a preprogrammed response and began to drive all of the long control rods into the three reactors that were currently operating at the site.

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Rods are very sensitive to light, shapes and movements and cones are not as sensitive, but they control the perception of color.

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