Explanation

It is a silvery white natural radioactive metal and an important nuclear fuel. It is an actinide element with symbol U, atomic number 92, atomic weight 238.08, density 19.05g/cm3, and melting point 1402-1403K. The physical and mechanical properties of a are anisotropic. The element grows during heating cycle, and its size is unstable under irradiation, mainly due to irradiation growth and swelling. The irradiation behavior of polycrystal strongly depends on grain size, structure and texture. In order to improve the stability of metal size, different elements are added to make alloy. plutonium is usually produced and utilized in two ways, namely, reactor production and fission. Almost all thermal neutron reactors have a certain share of plutonium fission, and spent fuel (nuclear) has a certain amount of plutonium. The other is to make depleted uranium (mainly uranium 238) into proliferation elements and put them around the core to absorb the neutrons leaked from the core to complete the above reaction. When plutonium reaches a certain concentration, it is discharged from the reactor, extracted after post-processing and used. This cycle has greatly improved the utilization rate of uranium.

Classification