摘要
标准物质在实验中用于监控实验数据的精准度、重现性和稳定性等参数,均一性是标准物质必须具备的重要特性。利用电子探针显微分析仪(EPMA)对MPI-DING合成玻璃标样进行了主量元素的测定,分析了合成玻璃的均一性质,将测定结果与推荐值对比,偏差基本在10%的范围以内,RSD基本小于5%,精密度较高,数据质量达到科学研究的要求。同时,利用电子探针对东太平洋大洋中脊火山玻璃进行主量元素的测定,测定结果与均值的SD小于1,表现出一定的均匀分配程度。对比MPI-DING玻璃标样与天然玻璃,MPI-DING系列合成玻璃主量元素在不同位置含量差异小,数据平稳,具良好的均一性;而天然玻璃不同位置元素含量不完全一致,达不到分析测试中标样的均一性要求。且不同的元素在不同岩性和酸碱度的样品中表现出的均一程度也不同,其中,Ca、K、Ti、Fe 4种元素在酸性和基性岩中的分配行为都较为均匀。
Reference materials are used in monitoring the accuracy,reproducibility and stability of the experimental data in in situ microanalysis.Homogeneity is important for reference materials.The MPI-DING glass was analyzed by an Electron Probe Micro Analyzer to discuss the homogeneity and stability of the synthetic glass.The results of major elements were compared with preferred value of other international laboratories and the deviation is basically within the range of 10%,meanwhile the RSD is mostly less than 5%.The results show that the data quality obtained from the electronic probe laboratory of Guilin University of Technology has reached the scientific research requirements.The electron probe was used to determine the major elements from the mid-oceanic ridges and volcanic glass of the eastern Pacific Ocean.The measurement results show that the homogeneity as SD is lower than 1.Compared with the data between the natural glass and the artificial glass,the content of elements in synthetic glass at different positions shows an even distribution.However,for the nature glass,elements in different locations are not absolutely homogeneous,and far below the standard homogeneity requirements.Different elements show different degree of homogeneity in different glass.Ca,K,Ti and Fe show more uniform distribution behavior in both acid and basic rocks.
引文
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