AMY is a newly-developed code of handling neutron induced transmutation and activation in materials. The code is based on Chebyshev rational approximation method (CRAM) to solve Bateman equations and to deal with complex pattern of chains produced by sequences of neutron reaction processes.Varieties of material activation properties are provided in AMY, including activity, decay heat, biological hazard, dose rate, clearance index and gamma source spectra. In order to verify the code, basic nuclear database in handbook of activation data was selected for comparing with FISPACT-2007. It shows that results of AMY are in good agreement with FISPACT-2007, and calculation efficiency of AMY is slightly higher than FISPACT-2007.

Considering fuel flow effect of reactor, neutron dynamic model was derived based on particle conservation equation and coupled with flow and heat transfer model. We developed a three-dimensional neutron/thermal-hydraulic coupled code and analyzed psychical property and thermal hydraulic characteristic of MOSART in transient state. It indicates that thermal hydraulic parameters influence greatly to psychical property of the core. Temperature negative feedback of liquid-fuel MSR is obvious.