0.1mg感量质量比较仪对标准气体称量不确定度的影响研究

Study on the influence of 0.1mg sensitivity mass comparator on the uncertainty of reference gas prepared by gravimetric method

通过对0.1mg感量的标准气体称量设备进行称量过程的不确定度来源进行探讨和量化,并使用标准方法进行称量结果不确定度的评估,得出使用0.1 mg感量质量比较仪进行标准气体称量时,单次称量的不确定度约为0.2mg。通过称样量的控制,最终获取的标准气体不确定度的原主要贡献源称量不确定度进一步降低,影响低于原料气纯度不确定度,甚至各组分摩尔质量的不确定度。使用0.1mg感量的标准气体称量设备进行标准气体称量时,标准气体的标准合成称量不确定度可低于0.02%以下。

The uncertainty source during the gravimetric procedure caused by the application of 0.1 mg sensitivity mass comparator is discussed and evaluated according to standard procedure.The uncertainty of one single weighing procedure is 0.2 mg by using 0.1 mg sensitivity mass comparator.By enlarge the filling amount of the component,the former main contribution(uncertainty of weighing)of the obtained reference gas become lower than other uncertainty sources such as the uncertainty of purity,even the uncertainty of mass molecular.The standard uncertainty of reference gas could be less than 0.02% while the reference gas is prepared by 0.1 mg sensitivity mass comparator.