【摘要】 阐述 3 1种农药在 3种电离方式 :电子轰击质谱 (EIMS)、正化学电离质谱 (PCIMS)和负化学电离质谱 (NCIMS)下的质谱特征和裂解规律 ,为农药残留的筛选和结构确证奠定基础。分别测定 1 8种有机氯农药、 1 3种有机磷农药的电子轰击质谱 (EIMS) ,正化学电离质谱 (PCIMS)和负化学电离质谱(NCIMS)。在EIMS中 ,有机氯农药主要产生 [M Cl]+ 、 [M HCl]+ 离子 ,有机磷农药主要产生磷酸基和磷酸酯基离子 ;在NCIMS中 ,[Cl]-或 [HCl2 ]-离子是有机氯农药的基峰 ,有机磷农药主要产生磷酸酯基负离子 ,某些芳香硫代磷酸酯还可产生重排离子 ;而在PCIMS中 ,大多数农药的灵敏度较低 ,没有观察到质谱。更多还原

【Abstract】 To illuminate the character of mass spectrum and fragmental roles of 31 pesticides in three modes of EIMS,NCIMS and PCIMS,and to provide foundation of screening of pesticide residues and structure confirmation.The EIMS,NCIMS and PCIMS of 18 organochlorides and 13 organophosphorous pesticides were determined.In EIMS,the organochlorides produced ions of[M-Cl] + and[M-HCl] +,and the organophosphorous pesticide yielded ions of phosphoric and phosphorate anion.The ion of[Cl] - or[HCl 2] - was usually responsible for the base peak of the organochloride,and the organophosphorate mainly produced phosphorate anion in NCIMS,the rearranged ions of some aromatic thiophosphate can also be observed.It can be mentioned that in PCIMS mode,most of pesticide had too low sensitivity to produce significant mass spectrum.The character of mass spectrum and fragmental roles of 31 pesticides in three modes of EIMS,NCIMS and PCIMS can provide foundation of screening of pesticide residues and structure confirmation.更多还原