核电站的核心设备是核反应堆 ,如图所示。在核反应堆中 ,用中子轰击铀核而引起裂变 ,铀核裂变时要放出更多的中子 ,且这些中子的速度都很大。由于铀核更容易俘获速度小的中子 ,所以必须设法减小快中子的速率 ,以便引起更多的铀核裂变 ,即发生链式反应。为此在铀棒周围放上减速 The core equipment of a nuclear power plant is a nuclear reactor as shown in the figure. In a nuclear reactor, the neutron bombards the uranium core and causes fission. When the uranium nuclear fission, more neutrons are released, and the speed of these neutrons is large. Since uranium nuclei are more likely to capture neutrons with lower velocities, it is necessary to try to reduce the rate of fast neutrons in order to cause more fission of uranium nuclei, ie a chain reaction occurs. To do this, put a deceleration around the uranium rod