论文部分内容阅读
目的建立悬浮液进样石墨炉原子吸收光谱法测定土壤中镍的方法。方法土壤样品经风干研磨后,通过300目尼龙筛后,利用0.15%琼脂溶液按比例稀释充分混匀后测定;并优化样品处理后悬浮液均匀稳定时间,通过对各步骤温度的调整来确定最佳程序升温条件;并对方法精密度、准确度和检出限进行验证。结果样品处理后悬浮液稳定时间能满足测定要求,程序升温采用两步干燥法,灰化温度为1 400℃25 s,原子化温度为2 300℃5 s,清除温度为2 450℃3 s,溶液在0μg/L~40μg/L时标准曲线线性良好,线性回归方程为y=0.003x+0.000 4,r=0.999 2,该方法的检出限为0.305 mg/kg,样品RSD为1.8%~2.0%,回收率为89%~109%。结论该方法应用悬浮液直接进样,方便快捷,具有良好的灵敏度、准确度,适合日常土壤样品中镍含量的检测。
Objective To establish a method for the determination of nickel in soil by graphite furnace atomic absorption spectrometry with suspension sampling. Methods After the soil samples were air-dried and ground, they were passed through a 300-mesh nylon mesh sieve and were diluted thoroughly with 0.15% agar solution to determine the optimum suspension time. The temperature of the suspension was optimized by adjusting the temperature of each step Good program temperature conditions; and methods of precision, accuracy and detection limits were verified. Results After the sample was processed, the stabilization time of the suspension was able to meet the determination requirements. The temperature was programmed by two-step drying, the ashing temperature was 1 400 ℃ for 25 s, the atomization temperature was 2300 ℃ for 5 s, the clearing temperature was 2 450 ℃ 3 s, The calibration curve of the solution was good at 0μg / L ~ 40μg / L, the linear regression equation was y = 0.003x + 0.000 4, r = 0.999 2, the detection limit was 0.305 mg / kg and the RSD was 1.8% 2.0%, the recovery rate of 89% ~ 109%. Conclusion The method of direct injection using the suspension, convenient and quick, with good sensitivity, accuracy, suitable for daily soil samples of nickel content detection.