Absolute Measurement Method for Electrolytic Conductivity Solution Based on Van Der Pauw Theory
LIN Zhen1,ZHANG Xiao1,WEI Jia-li2,WANG Xiao-ping2,YU Xiang2
1. Zhejiang Province Institute of Metrology, Hangzhou, Zhejiang 310013, China;
2. State Key Laboratory for Modern Optical Instrumentation, Zhejiang University, Hangzhou, Zhejiang 310027, China
Abstract:The application of Van Der Pauw theory to solution electrical conductivity measurement is proposed innovatively, a closed four-electrode conductivity cell is designed. A micro AC current source is used to provide excitation signals,control circuit is used to process signals and communicate with computer.A series of experiments are carried out to study the influence factors of Van Der Pauw method.The tests of the reference materials proved the measurement range of the method is 0~40 mS/cm,the measurement error is under ±1%,which can be used for primary standard methods.
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