土壤中硝化抑制剂DMPP含量的气相色谱测定法

建立了一种检测土壤中吡唑类硝化抑制剂DMPP含量的气相色谱法。DMPP在NaOH溶液中可定量转化为DMP,从5种有机溶剂中选择氯仿作为DMP的萃取剂。本文采用吡啶做为内标物,内标校正因子fDMP和fDMPP分别为1.6775和3.3884。通过DB-1701气相色谱柱,氢火焰离子化检测器(FID)定量检测氯仿溶液萃取相中的DMP。本法添加回收率为97.4%～98.8%;RSD为0.70%～2.09%;土壤中DMPP的检出限为0.4mgkg-1。应用本法测定在潮棕壤中10℃、20℃和30℃时DMPP的降解半衰期分别为大于28d、14d和7d。

Determination of Nitrification Inhibitor DMPP in Soil by Gas Chromatography

A new method was developed to determine nitrification inhibitor DMPP in soil with gas chromatography based upon the transformation of DMPP to DMP in NaOH solution. Chloroform was found to be the best extractant in five organic solvents tested. Pyridine was applied as the internal standard and the correcting factors for internal standard of DMP and DMPP were 1.6775 and 3.3884, respectively. A DB-1701 column and a flame-ionization detector (FID) were used for the GC determination of DMP. The results showd that the rate of recovery was 98.1%-99. 5%, the coefficient of variation was 0.84%-1.55%, and the detection limit of DMPP in soil was 0.4mg kg-1. Half-lives of DMPP in meadow brown earth at 10℃, 20℃ and 30℃ were excessive 28d, 14d and 7d, respectively, determined by using this method.