1·Analysis of the activated background spectrum shows that natural copper is an ideal shielding material in fast neutron nuclear reactions.
通过分析天然铜的活化本底谱，可以看出它是快中子核反应中的最理想的屏蔽材料之一。
2·The fundamental reactor physics characteristics of the fast neutron reactor with the heavy metal lead as coolant are discussed.
讨论了以重金属铅作为冷却剂的快中子核反应堆的基本堆物理特征。
3·The results showed that the contents of DNA decreased strongly with increasing dose of fast neutron.
结果表明，快中子辐照处理后，幼苗dna含量显著下降，并随着剂量增大而降低。