1. School of quality and technical supervision, Hebei University 1 , Baoding, Hebei 071000, China
2. National and Local Joint Engineering Research Center for Measuring Instruments and Systems 2 , Baoding, Hebei 071000, China
3. Hebei Key Laboratory of Energy Metering and Safety Testing Technology, Hebei University 3 , Baoding, Hebei 071000, China
4. Department of Chemical Engineering, University of Chester 4 , Chester CH2 4NU, United Kingdom