深入研究了β-O-4型木质素模型化合物———愈创木基丙三醇-β-愈创木基醚的合成新路线,并利用红外光谱和核磁共振谱对其化学结构进行了分析。采用由Cu2+/吡啶/过氧化氢组成的GIF(GIF sur YVETTE)型仿酶体系对这一木质素模型物进行了... 深入研究了β-O-4型木质素模型化合物———愈创木基丙三醇-β-愈创木基醚的合成新路线,并利用红外光谱和核磁共振谱对其化学结构进行了分析。采用由Cu2+/吡啶/过氧化氢组成的GIF(GIF sur YVETTE)型仿酶体系对这一木质素模型物进行了仿酶降解的研究,并采用GC-MS、13CNMR等方法分析了该β-O-4型木质素模型化合物在降解过程中的结构变化,在此基础上对这种仿酶降解的机理进行了探讨。研究结果表明:利用溴化铜对4-乙酰基愈创木酚进行溴化后很容易得到4-(α-溴化乙酰基)-愈创木酚中间体,从而提高了合成愈创木基丙三醇-β-愈创木基醚的效率。GIF仿酶降解体系对β-O-4型木质素模型物有较强的碎解能力,降解后产生一系列含羟基、醛基和羧基的芳香族低分子化合物,根据反应产物的结构可以说明β-O-4型木质素模型化合物的主要降解途径为:β-O-4醚键断裂、Cα—Cβ键断裂、Cβ—Cγ键断裂。本研究为该仿酶降解体系在无污染漂白工业上的应用提供理论依据。展开更多
The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the re...The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the reaction solution pH rangingfrom4to11.The relatively ultrathin Bi2WO6nanoflakes prepared at pH4showed excellent adsorption and photodegradationefficiency towards norfloxacin.The characterization results showed that Bi2WO6prepared at pH4had a larger specific area andfaster photo-generated carrier separation rate.The decay rate reached the maximum in weak alkaline reaction solution,which couldbe attributed to the presence of moderate OH-anions.The present study demonstrated that the smaller size of Bi2WO6could be anefficient photocatalyst on the degradation of norfloxacin in the aquatic environment.展开更多
The factors and mechanisms of oxidative degradation of three organophosphorus pesticides （dichlorvos, methamidophos and phoxim） were studied with sodium percarbonate （SPC） as a solid oxidant. The result showed tha...The factors and mechanisms of oxidative degradation of three organophosphorus pesticides （dichlorvos, methamidophos and phoxim） were studied with sodium percarbonate （SPC） as a solid oxidant. The result showed that SPC has highly activity in degrading these organophosphous pesticides. The most efficient degradation of pesticides occurred under basic conditions and the degradation rates increased with time extension and high temperature. The degradation of organophosphorus pesticides was expected to get even better results at lower initial concentration. Furthermore, we analyzed the intermediate products by NMP, spectrometry. On the basis of the analytical result, the oxidative degradation mechanism was proposed for each organophosphous pesticide. It is significant to understand the environment chemistry of organophosphorus pesticides in environmental system.展开更多
文摘 深入研究了β-O-4型木质素模型化合物———愈创木基丙三醇-β-愈创木基醚的合成新路线,并利用红外光谱和核磁共振谱对其化学结构进行了分析。采用由Cu2+/吡啶/过氧化氢组成的GIF(GIF sur YVETTE)型仿酶体系对这一木质素模型物进行了仿酶降解的研究,并采用GC-MS、13CNMR等方法分析了该β-O-4型木质素模型化合物在降解过程中的结构变化,在此基础上对这种仿酶降解的机理进行了探讨。研究结果表明:利用溴化铜对4-乙酰基愈创木酚进行溴化后很容易得到4-(α-溴化乙酰基)-愈创木酚中间体,从而提高了合成愈创木基丙三醇-β-愈创木基醚的效率。GIF仿酶降解体系对β-O-4型木质素模型物有较强的碎解能力,降解后产生一系列含羟基、醛基和羧基的芳香族低分子化合物,根据反应产物的结构可以说明β-O-4型木质素模型化合物的主要降解途径为:β-O-4醚键断裂、Cα—Cβ键断裂、Cβ—Cγ键断裂。本研究为该仿酶降解体系在无污染漂白工业上的应用提供理论依据。
基金Projects(51579096,51222805,51521006,51508175) supported by the National Natural Science Foundation of ChinaProject supported by the National Program for Support of Top-Notch Young Professionals of China+1 种基金Project(NCET–11–0129) supported by the Program for New Century Excellent Talents in University from the Ministry of Education of ChinaProject(CX2015B095) supported by the Hunan Province Innovation Foundation for Postgraduate,China
文摘The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the reaction solution pH rangingfrom4to11.The relatively ultrathin Bi2WO6nanoflakes prepared at pH4showed excellent adsorption and photodegradationefficiency towards norfloxacin.The characterization results showed that Bi2WO6prepared at pH4had a larger specific area andfaster photo-generated carrier separation rate.The decay rate reached the maximum in weak alkaline reaction solution,which couldbe attributed to the presence of moderate OH-anions.The present study demonstrated that the smaller size of Bi2WO6could be anefficient photocatalyst on the degradation of norfloxacin in the aquatic environment.
文摘The factors and mechanisms of oxidative degradation of three organophosphorus pesticides （dichlorvos, methamidophos and phoxim） were studied with sodium percarbonate （SPC） as a solid oxidant. The result showed that SPC has highly activity in degrading these organophosphous pesticides. The most efficient degradation of pesticides occurred under basic conditions and the degradation rates increased with time extension and high temperature. The degradation of organophosphorus pesticides was expected to get even better results at lower initial concentration. Furthermore, we analyzed the intermediate products by NMP, spectrometry. On the basis of the analytical result, the oxidative degradation mechanism was proposed for each organophosphous pesticide. It is significant to understand the environment chemistry of organophosphorus pesticides in environmental system.
