火焰原子吸收光谱法测定云冈石窟岩缝结晶物中的Mg

Determination of Mg in the Crystal of Yungang Grottoes Rock Chink by Flame Atomic Absorption Spectrometry

采用火焰原子吸收光谱法对云冈石窟岩缝结晶物中Mg的含量进行了测定。样品研细过筛后,采用3 mol/L HNO3溶解,用锶溶液做干扰抑制剂,标准曲线法测定。Mg的浓度在0.00～0.60μg/mL之间与吸光度有良好的线性关系,线性回归方程为A=1.282 2 c-0.001 4,相关系数r=0.998 9。相对标准偏差为1.36%(n=10),方法的检出限为0.002 3μg/mL(3σ),加标回收率为96.4%～100.2%。

A flame atomic absorption spectrometry（FAAS） procedure was presented for the determination of magnesium content in the Crystal of Yungang Grottoes rock crack.The sample was dissolved in 3 mol / L HNO3 after it has been milled until through 200 mesh sieve,the solution of SrCl2 was used as the antijamming agent.A standard calibration curve was used with a linear working range of 0.00 ～ 0.60 μg / mL（correlation coefficient r = 0.998 9）,the linear equation for calcium was A = 1.282 2 c-0.001 4.The reliability of the procedure was established by repeat experiments with the relative standard deviation 1.36%（n=10）,the detection limit of this method for Mg（II） was 0.002 3 μg / mL（3σ）,and recovery ranging from 96.4% ～ 100.2%.