1. College of Materials Science and Engineering, Chongqing University, Chongqing 400044, P.R. China
2. Chongqing Key Laboratory of Vanadium−Titanium Metallurgy and New Materials, Chongqing University, Chongqing 400044, P.R. China
3. Spectris Instrumentation and Systems Shanghai, Ltd., Shanghai 200233, P.R. China