离子电极法测定土壤中氟化物的方法研究

[目的]为离子电极法快速测定土壤中氟化物含量的推广与应用提供理论依据。[方法]准确称取土壤3．00g，置于蒸馏瓶中蒸馏，加150μg／ml乙酸钠和10．00ml总离子强度调节缓冲液，用离子电极法测定土壤中氟化物含量。并对样品溶液pH值、温度对电极电位和标准曲线斜率的影响等测定条件进行优化。[结果]在测试样品中添加适量的氟化物标准溶液，按样品测定的全过程加标试验时，样品的加标回收率均在90％以上，重复性测试的标准偏差为0．001，变异系数为3．700％。[结论]离子电极法能满足测定土壤中氟化物含量的需要，且测定的精密度与准确度较高，快捷简便，有助于推广。

Research on the Determination of Fluoride in the Soil by Ion Electrode Method

[Objective] The study aimed to provide theoretical basis for the popularization and application of determining fluoride content in the soil by ion electrode method accurately.[Method] 3.00 g soil was accurately taken and placed into the distillation bottle for distillation.Then 150 μg/ml sodium acetate and 10.00 ml total ionic strength adjustment buffer were added.The content of fluoride in the soil was determined by ion electrode method.And the determination conditions such as the effects of sample solution pH value and temperature on the electrode potential and the standard curve slope were optimized.[Result] Fluoride standard solution with appropriate amount was added in test samples and they were detected according to the whole process of sample determination.Then the recovery of standard sample addition was more than 90%,the standard deviation of repeatability test was 0.001 and the variation coefficient was 3.700%.[Conclusion] Ion electrode method could meet the needs of determining fluoride content in the soil with higher detection precision and accuracy,which was helpful to be generalized.