【摘要】 采用探针恒温原子化技术的石墨炉原子吸收 ,测定高纯金属镁中的痕量铝 ,利用样品中的基体镁转化成硝酸镁成为一种有效基体改进剂 ,进一步改善了铝的分析性能。实验优化了仪器条件和分析方法。结果表明 ,在有Mg(NO3) 2 存在时 ,可显著提高探针原子化测铝的灰化温度 ,降低原子化温度 ,并且使铝的灵敏度提高了 50 %。方法的检出限为 2 .2× 1 0 - 1 1 gAl,测定 50 μg/LAl标准溶液的相对标准偏差 (n =1 2 )为 3.1 %。用该法测定了 4个金属镁内部管理样品中Al的含量 ,结果与推荐值相符合 ,其RSD(n =6)为 3.4%～ 1 1 .0 %。更多还原

【Abstract】 A method for the determination of trace aluminum in high purity magnesium by probe atomization graphite furnace atomic absorption spectrometry has been developed. The magnesium in the sample is transferred into Mg(NO 3) 2 and applied as a matrix modifier that can further improve the analytical performance of Al. The instrument operating conditions and determination conditions are optimized. The experimental results show that the ashing temperature is increased observably and the optimum atomization temperature is decreased when Mg(NO 3) 2 is used as matrix modifier for the determination of Al. The detection limit for Al is 2.2×10 11 g. The method has been applied to the determination of Al in 4 high purity magnesium reference samples. The results are in agreement with recommended values with precision of 3.4%～11% RSD ( n =6).更多还原