石墨炉原子吸收法测定不锈钢食具镉镉元素迁移量的不确定度评估

摘要

The cadmium content migrating from stainless steel food containers to soak solution with acetic acid was determined with graphite furnace atomic absorption spectrometry according to GB/T 5009.81-2003, and the measurement uncertainty was evaluated according to the evaluation principle and method. Through analyzing the uncertainty sources, each component of uncertainty was evaluated and quantified, and then the expanded uncertainty was calculated. When measurement result was 0.000 30 mg/dm2, the expanded uncertainty was 0.000 013 mg/dm2, and the combined standard uncertainty was 0.000 03 mg/dm2(coverage factork=2).%石墨炉原子吸收法测定不锈钢食具镉元素迁移量的不确定度，依据测量不确定度的评定原理和方法，对GB/T 5009.81-2003中不锈钢食具乙酸浸泡液的镉迁移量进行不确定度来源分析，量化不确定度分量，最后得出扩展不确定度。当测量结果为0.00030 mg/dm2，合成标准不确定度为0.000013 mg/dm2，扩展不确定度为0.00003 mg/dm2（包含因子k=2）。