mean neutron lifetime

例句：

1. 1.The mean neutron lifetime of the isotope is about 20 minutes.
   该同位素的中子寿命大约为20分钟。
2. 2.The researcher found that the mean neutron lifetime of the material was significantly longer than expected.
   研究人员发现，这种材料的中子寿命显著长于预期。
3. 3. In nuclear physics, the mean neutron lifetime is a crucial parameter for understanding nuclear reactions.
   在核物理学中，中子寿命是理解核反应的关键参数。