pX测量误差不确定度评定时离子活度系数处理方法的探讨  

Discussion on the Processing of the Ion Activity Coefficient in the Uncertainty Evaluation of pX Measurement Errors

作　　者：修宏宇[1] 贺新洋[1] XIU Hongyu;HE Xinyang(National Institute of Metrology,Beijing 100029,China)

机构地区：[1]中国计量科学研究院,北京100029

出　　处：《计量科学与技术》2022年第9期28-32,共5页Metrology Science and Technology

摘　　要：pX测量通常采用基于电化学分析原理的实验室离子计,测量前需用标准溶液标定工作曲线。由于标定用标准溶液的配制值为浓度值,仪器响应量是活度值,而活度与浓度是两个不同的量,活度系数的不可测量性及差异,使得pX测量存在较大的测量误差。本文以一次实验数据为例,探讨了在pX测量误差的不确定度评定时,对活度系数不确定度的一种处理方法。pX measurement is usually carried out by laboratory ion meter based on the principle of electrochemical analysis,and the working curve needs to be calibrated with a standard solution before measurement.Since the prepared value of the standard solution for calibration is the concentration value and the instrument response quantity is the activity value,and activity and concentration are two different quantities,the unmeasurable and difference of the activity coefficient make the pX measurement have a large measurement error.In this paper,a processing method of the activity coefficient in the uncertainty assessment of the pX measurement error is discussed,taking the data of one experiment as an example.

关 键 词：实验室离子计 pX测量误差 不确定度评定 活度系数 

分 类 号：TB97[一般工业技术—计量学]