影响微肥中锌含量检测准确度因素的分析

Analysis on Factors that Affect Zinc Level Test Accuracy in Foliar Fertilizer of Trace Elements

[目的]为了解决检验过程中存在的问题，降低系统误差和偶然误差，提高检测的准确度。[方法]通过分析GB／T17420《微量元素叶面肥料》中双硫腙比色法，找出检测锌含量易出现影响准确度的因素，优化检测方法，做好样品前处理，控制吸取样品稀释液中Zn含量（预计试样中锌含量在1．00～10．00μg之间）。[结果]根据在微酸性溶液中锌与双硫腙反应生成酮式配合物，再用四氯化碳萃取，所取溶液呈稳定的紫红色的原理，用双硫腙比色法检测，使检测结果误差在标准规定允许差范围之内，降低检测中存在的系统误差和偶然误差，提高检测准确度。[结论]该研究可以为科学指导肥料生产企业加工生产及农业生产运用提供参考。

[ Objective] The research aimed to solve the problems in the determination, decrease the system error and accidental system, and increase the accuracy of the determination. [ Method] By analyzing Dithizone Colorimetry from GB/T17420 Foliar Fertilizer of Trace Elements, the factors that affected accuracy were found out whilethe test methods were optimized, the sample preliminary treatment was completed, and the zinc levels from absorbing sample dilution （the zinc levels of the sample dilution are predicted to be between 1.00 - 10. O0 p,g） was con- trolled. [ Result] In compliance with the reaction principle of stable fuchsia of the solution extracted from carbon tetrachloride, through which the ketone complexes could be produced by zinc and dithizone in acidic solution. This was favorable for colorimetric analysis, and enableed the deviation of test result to be within the limit of the standard, so that it reduced the systematic deviation and incidental deviation existing in the process of test, improved the test accuracy. [ Conclusion] The research could provide the scientific basis for the fertilizer manufacturers scien- tifically to get on track and agricultural application.