X射线荧光光谱法测定锰矿石中锰的不确定度评定  

Uncertainty Evaluation of the Determination of Manganese in Mn Ore by XRF

作　　者：张永文[1] 张争京 王全宏[1] 刘文俊[1] 

机构地区：[1]武警黄金第五支队,陕西西安710100

出　　处：《广东化工》2013年第16期211-213,共3页Guangdong Chemical Industry

摘　　要：文章从X射线荧光光谱测试方法的特点入手,分四个方面评定了X射线荧光光谱法测定锰矿石中锰的不确定度。根据高斯分布,以计数率的不确定度表示测量过程中的不确定度;由于标准物质只给出标准偏差,为计算标准物质的不确定度,选择标准物质最低测量次数n=5计算其不确定度。通过对锰的不确定度的评定认为:在锰的测试过程中影响其不确定度的关键因素为曲线拟合,其次是标准物质的不确定度,再次是样品制备过程。样品称量和仪器稳定性的不确定度对合成不确定度的影响很小。XRF is widely used in the testing of geological samples. The analysis report contains the test result and uncertainty, so the user of the report can know the reliability. And on the same time, the result by XRF can be compared easily with other methods. In XRF the uncertainty of the result can be affected by many factors. To evaluate all the influencing factors is impossible. So based on the theory of XRF, the writer sum up the main factors. Uncertainty of the determination of manganese in Mn ore was evaluated from four aspects. Based on Gaussian distribution, the uncertainty of count rate was used to replace the uncertainty of the measuring process. Because the uncertainty of standard was unknown, there is only standard deviation, but the number of tests is unknown, we can＇t calculate the uncertainty directly. So the least number of measure 5 is used to calculate the uncertainty of standard. By the means of uncertainty evaluated, we discovered that the key factor which influence the uncertainty in the process of test is curve fitting, secondly is the uncertainty of the standard, thirdly is the process of sample preparation. The influence of sample weighing and stability of the instrument is very small.

关 键 词：X射线荧光光谱 不确定度 锰矿石 高斯分布 

分 类 号：O65[理学—分析化学]