摘要
为明确氯氟醚菌唑的光降解规律,本文建立了氯氟醚菌唑在水溶液和土壤中的液相色谱残留检测方法,系统地研究了氯氟醚菌唑在液相、玻片表面和土壤表面的光化学降解及影响因素,并鉴定了其在乙腈中的光解产物。结果表明:氯氟醚菌唑的光解速率随着其初始浓度的增大而减慢;氯氟醚菌唑在中性与碱性条件下的光解速率均较快且差异较小,在酸性条件下降解最慢,半衰期是中性条件下的32倍。吡唑醚菌酯可抑制氯氟醚菌唑的光解,当吡唑醚菌酯与氯氟醚菌唑比例为2∶1时,抑制作用最显著,其半衰期是未加吡唑醚菌酯的2倍;Fe3+和Fe2+对氯氟醚菌唑的光解均表现为抑制作用,且Fe3+对氯氟醚菌唑光解的抑制作用更为显著;氯氟醚菌唑在有机溶剂中的光解速率大小依次为乙腈>甲醇>乙酸乙酯>正己烷;氯氟醚菌唑在乙腈中的主要光解产物为4-[2-羟基-1-(1H-1,2,4-三唑-1-基)丙-2-基]-5-(三氟甲基)苯-1,2-酚、2-[4-苯氧基-2-(三氟甲基)苯基]-1-(1H-1,2,4-三唑-1-基)丙-2-醇和M750F005。研究表明,氯氟醚菌唑在液相和玻片表面均属于易光解农药,在土壤表面属于难光解农药。
In order to clarify the photolysis law of mefentrifluconazole,a liquid chromatography method for the residue analysis of mefentrifluconazole in aqueous solution and soil was established.Based on the above method,the kinetic parameters and influencing factors of the photochemical degradation of mefentrifluconazole in liquid phase,on glass surface and on soil surface were systematically studied,and the photolysis products in acetonitrile were identified.The results showed that the photolysis rate of mefentrifluconazole decreased with the increase of the initial concentration.The photolytic rate of mefentrifluconazole was faster under both neutral and alkaline conditions,and the degradation rate was the slowest under acidic conditions.The half-life of mefentrifluconazole was 32 times that under neutral conditions.It was found that pyraclostrobin could inhibit the photochemical degradation of mefentrifluconazole,with the inhibition reaching the highest level when the mixture ratio of pyraclostrobin and mefentrifluconazole was 2∶1,and the half-life was twice as long as that without pyraclostrobin.In addition,both Fe3+and Fe2+showed inhibitory effects on the photolysis of mefentrifluconazole,and at the same concentration,Fe3+showed a higher photodegradation inhibition level.The photolysis rates of mefentrifluconazole in different organic solvents followed the rule of acetonitrile>methanol>ethyl acetate>n-hexane.The main photodegradation products in acetonitrile were 4-[2-hydroxy-1-(1H-1,2,4-triazol-1-yl)propan-2-yl]-5-(trifluoromethyl)benzene-1,2-diol,2-[4-phenoxy-2-(trifluoromethyl)phenyl]-1-(1H-1,2,4-triazol-1-yl)propan-2-ol and M750F005.Mefentrifluconazole is a pesticide where photodecomposition happens easily in the liquid phase and on glass slides,and with more difficulty on the soil surface.
作者
钟言茹
孔令茹
孙晓芳
王鸣华
施海燕
ZHONG Yanru;KONG Lingru;SUN Xiaofang;WANG Minghua;SHI Haiyan(College of Plant Protection,Nanjing Agricultural University,Nanjing 210095,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2023年第5期1023-1031,共9页
Journal of Agro-Environment Science
基金
国家重点研发计划项目(2021YFD1700104)。
关键词
氯氟醚菌唑
液相中光解
玻片表面光解
土壤表面光解
光解产物
mefentrifluconazole
photolysis in liquid phase
photolysis on glass surface
photolysis on soil surface
photolysis products
