多菌灵的γ射线辐照降解机理研究

发布时间：2018-07-11 14:23

本文选题：γ辐照 + 多菌灵　；参考：《原子能科学技术》2017年02期

【摘要】：采用γ射线辐照技术降解多菌灵,考察了不同初始条件对多菌灵降解效果的影响,并通过液相色谱-质谱(LC-MS)技术和量子化学计算分析了多菌灵在水溶液中的降解产物和降解路径。结果表明:γ射线能有效降解多菌灵,初始浓度越低、吸收剂量越大,多菌灵的降解率越高;·OH自由基、·H自由基和水合电子e_(aq)~-在辐照降解过程中的贡献大小依次为·OH、·H、e_(aq)~-。LC-MS检测到m/z=119、134、208的降解产物。多菌灵的键级、键长和NBO电荷等量子化学信息能很好地解释LC-MS检测到的降解产物,结合LC-MS检测结果和量子化学分析得到的多菌灵的降解路径为:多菌灵在自由基的进攻下降解生成5-羟基多菌灵、2-氨基苯并咪唑和苯并咪唑,2-氨基苯并咪唑和苯并咪唑在自由基的进攻下继续降解为分子量更小的物质。
[Abstract]:The effects of different initial conditions on the degradation of carbendazim were investigated by 纬 -ray irradiation. The degradation products and pathways of carbendazim in aqueous solution were analyzed by liquid chromatography-mass spectrometry (LC-MS) and quantum chemistry. The results show that 纬 -ray can effectively degrade carbendazim, and the lower the initial concentration, the greater the amount of absorbent. The higher the degradation rate of carbendazim is, the higher the contribution of OH radical, H radical and hydrated electron E _ (aq) ~ (-) in the irradiation degradation process is, and the degradation product of m/z=119134208 is detected by m/z=119134208 _ (aq) ~ (-) -.LC-MS. The bond order, bond length and NBO charge of carbendazim can explain the degradation products detected by LC-MS. In combination with LC-MS results and quantum chemical analysis, the degradation pathways of carbendazim are as follows: carbendazim degrades under the attack of free radicals to produce 5-hydroxycarbendazim 2-aminobenzimidazole and benzimidazolium 2-aminobenzimidazole and benzo. Imidazole continues to degrade into less molecular weight substances under the attack of free radicals.
【作者单位】：南京航空航天大学材料科学与技术学院;
【基金】：江苏省自然科学基金资助项目(BK20131355) 国家自然科学基金资助项目(11575086) 江苏高校优势学科建设工程资助项目
【分类号】：TQ455;O571.323

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