The results showed that the sample exhibits insulator behavior on the whole measuring temperature range,and the transport mechanism meets the variable range hopping model;charge ordering(CO)phase exists in the sample,the transition temperature TCO≈240K,and the sample exhibits paramagnetism(PM)→charge ordering(CO)→antiferromagnetism(AFM)transition with temperature decreasing.

Microstructure evolution of Ni-Ni_3Nb alloy at an abruptly changing velocity under directional solidification;

Firstly, the concept of active transition is proposed and its performance equivalent model is put forward under resource-constrained circumstances.