作者：方正, 周鑫, 霍玉朋, 董了瑜, 李志昂
作者单位：中国测试技术研究院, 四川 成都 610021
关键词：电子质量比较器;称量;不确定度;线性;标准砝码
摘要：
重量法制备混合气体是通过依次准确称量组分转移前后的气瓶质量差来计算加入组分的质量。该文选用目前应用广泛的灵敏度高、称量重复性好的电子质量比较器，量程：0～10100 g，精度：0.001 g，当气体组分加入量5 g时，使用标准砝码研究质量比较器称量示值与实际加入质量值之间的线性关系，建立采用比较法称量来计算加入组分质量的数学模型，评定该方法的标准不确定度。结果表明称量过程引入的标准不确定度与气瓶中加入气体原料的压力正相关，按照实际充装压力最大值（100 bar）计算，称量过程引入的标准不确定度为0.0088 g。
Weighing uncertainty evaluation on electronic mass comparator for gravimetric preparation of reference gas mixture
FANG Zheng, ZHOU Xin, HUO Yupeng, DONG Liaoyu, LI Zhiang
National Institute of Measurement and Testing Technology, Chengdu 610021, China
Abstract: Gravimetric preparation of reference gas mixing was used to calculate the mass of added components by successively and accurately weighing the mass of cylinder difference before/after component transfer. In this article, a widely used electronic mass comparator (measuring range:0-10 100 g, precision:0.001 g) with high sensitivity and excellent weighing repeatability was chosen, and the linear relation between weighing indicating mass of mass comparator and real mass was researched by using standard weights when the gas adding amount was more than or equal to 5 g. Besides, standard uncertainty of the method was also evaluated. The result indicated that standard uncertainty introduced during weighing is positively correlated with the pressure of raw gas added in cylinder. The standard uncertainty is calculated to be 0.008 8 g based on the maximum actual filling pressure (100 bar).
Keywords: electronic mass-comparator;weighing;uncertainty;linearity;standard weights
2016, 42(12): 38-41 收稿日期: 2016-02-19;收到修改稿日期: 2016-04-03
基金项目: 国家科技支撑计划项目（2013BAK12B04）四川省科技支撑计划项目（2015GZ0084，2015GFW0046）
作者简介: 方正(1963-),男,辽宁沈阳市人,研究员,研究方向为标准物质制备方法及化学计量量值溯源体系。
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