电子探针定量分析绿松石实验条件的探究

Study on the Experimental Conditions of Quantitative Analysis of Turquoise by Electron Probe

绿松石是一种珍贵的玉石,在进行微区无损分析时,电子探针常用于绿松石的矿物组成及分布研究。由于自然产出的绿松石不仅含结晶水、结构水,还因孔隙发育常含不定量的吸附水,易致绿松石的电子探针定量分析结果不佳,总量偏低;除此之外,标样和测试条件的选择对测试结果的影响也至关重要。采用岛津电子探针对绿松石进行定量分析,通过设定不同的加速电压、束流和束斑直径,分析不同测试条件对定量结果的影响,从而得出绿松石最佳的定量分析条件。结果表明:当选择加速电压15 kV、束流为10 nA或20 nA、束斑直径为1μm时,测得的绿松石总量区间为79.95%~81.23%,接近绿松石理论总量79.88%~81.35%,测试结果最佳。本实验旨在建立一套适用于绿松石电子探针定量分析的最优测试条件,对绿松石电子探针定量分析具有一定的参考意义和应用价值。

Turquoise is a kind of precious gem.Electron probe is often used to study the mineral components and distribution of turquoise in micro-zone non-destructive analysis.Natural turquoise not only contains crystal water and structural water,but also often contains unquantified adsorption water due to the pore development.Therefore,it is easy to cause the inaccuracy of the quantitative analysis results of turquoise electron probe test,and the total amount is low.In addition,the selection of standard samples and test conditions is also very important to the test results.So far,no relevant research has been found on the influence of different test conditions on the results of quantitative analysis of turquoise electron probe test.In this paper,Shimazu electron probe(EPMA-1720)was used for quantitative analysis of turquoise.By setting different acceleration voltage,beam current and beam spot diameter,the influence of different test conditions on quantitative results was analyzed,and the optimal quantitative analysis conditions of turquoise were obtained.The results show that when the acceleration voltage is 15 kV,the beam current is 10 nA or 20 nA,and the beam spot diameter is 1μm,and the range of total turquoise measured is 79.95%-81.23%,which is close to the theoretical total turquoise 79.88%-81.35%,and the test result is the best.This experiment aims to establish a set of optimal test conditions suitable for quantitative analysis of turquoise electron probe test,which has certain reference significance and application value.