不同石墨管性能对西藏土壤中铅测定的影响

Effect of Different Graphite Tube Properties on the Determination of Lead in Tibet Soil

摘要采用热解涂层石墨管、长寿命石墨管和普通石墨管测定土壤样品中的铅，以研究不同石墨管灵敏度、检出限、精密度和准确性。试验结果表明：热解涂层石墨管性能略优于其他两个石墨管，最优灰化和原子化温度分别为700℃和1150℃，其使用寿命和长寿命石墨管相似，测定次数达到800次时，灵敏度和检出限都可以满足分析要求，测定西藏土壤加标回收率在98．6％-105．2％之间，RSD小于2．1％，测定土壤标物值与证书值较接近，结果较为满意。

Abstract The content of lead in soil samples was measured graphite tube （PGT）, Extended Lifetime Cuvetes （ELC） and Nomal precision and accuracy of different graphite tube were investigated. PCT slightly was better than the other two graphite tube. the optimal by three different graphite tube, Pyrolyzate coating graphite tube （NGT）. The sensitivity, detection limit, Experimental results showed that the performance of ashing and atomization temperature of PCT were 700℃and 1150℃respectively, and its service life was similar to ELC. During the 800 determination times, its sensitivity and detection limit can meet the requirement of the analysis, and the recovery rate of determination of lead in Tibet soil was in the range of 98.6%- 103.2 %, RSD was less than 2.1%, the determination of soil standard value was close to the value of certificate, and the result was proved satisfactory.