1. MOE Key Laboratory of New Processing Technology for Nonferrous Metal and MaterialsGuangxi Key Laboratory of Optical and Electronic Materials and DevicesCollege of Materials Science and EngineeringGuilin University of Technology Guilin 541004 P. R. China
2. Department of Machine Intelligence and Systems EngineeringFaculty of Systems Science and TechnologyAkita Prefectural University Yurihonjo 015‐0055 Japan
3. College of Chemistry and Chemical EngineeringYantai University Yantai 264005 P. R. China