Due to some deficiencies of the polysaccharides degradation by the methods of chemical,thermal or enzymatic treatment,sonication was introduced for the degradation of Porphyra yezoensis polysaccharide(PYPS).The Mark-H...Due to some deficiencies of the polysaccharides degradation by the methods of chemical,thermal or enzymatic treatment,sonication was introduced for the degradation of Porphyra yezoensis polysaccharide(PYPS).The Mark-Houwink equation,showing the relationship between molecular weight and intrinsic viscosity,was set up.It was found from the results of the degradation dynamics that there was an exponential relation between the rate constant and treatment time of sonication,different from the traditional chemical,thermal or enzymatic treatment.The activation energy of the degradation was 52.13 kJ·mol-1,and it could be preliminarily concluded that ultrasonic degradation was better than the enzymatic ones.展开更多
研究考察了CCl4增强超声降解喹诺酮类抗生素环丙沙星的效果,通过·OH浓度的测定和异丙醇对反应的抑制情况探索环丙沙星的超声降解机理;采用UPLC/MS/MS方法对降解产物进行分析,解析环丙沙星的降解路径。结果表明,CCl4增强了环丙沙星...研究考察了CCl4增强超声降解喹诺酮类抗生素环丙沙星的效果,通过·OH浓度的测定和异丙醇对反应的抑制情况探索环丙沙星的超声降解机理;采用UPLC/MS/MS方法对降解产物进行分析,解析环丙沙星的降解路径。结果表明,CCl4增强了环丙沙星的超声降解,当反应液体积为100 m L,超声40 min,随着CCl4添加浓度的增大（0-41.4mmol·L^-1）,环丙沙星的降解率由0.51%增至50.92%;荧光探针分析和异丙醇抑制结果表明增强作用主要在于·OH和一系列氯自由基的氧化;UPLC/MS/MS分析发现,降解过程中生成8种产物,其中包括3种氯代产物,环丙沙星按照6种途径进行降解。研究结果有助于深入研究CCl4增强超声降解抗生素的机理,提高过程处理效果。展开更多
文摘Due to some deficiencies of the polysaccharides degradation by the methods of chemical,thermal or enzymatic treatment,sonication was introduced for the degradation of Porphyra yezoensis polysaccharide(PYPS).The Mark-Houwink equation,showing the relationship between molecular weight and intrinsic viscosity,was set up.It was found from the results of the degradation dynamics that there was an exponential relation between the rate constant and treatment time of sonication,different from the traditional chemical,thermal or enzymatic treatment.The activation energy of the degradation was 52.13 kJ·mol-1,and it could be preliminarily concluded that ultrasonic degradation was better than the enzymatic ones.
文摘研究考察了CCl4增强超声降解喹诺酮类抗生素环丙沙星的效果,通过·OH浓度的测定和异丙醇对反应的抑制情况探索环丙沙星的超声降解机理;采用UPLC/MS/MS方法对降解产物进行分析,解析环丙沙星的降解路径。结果表明,CCl4增强了环丙沙星的超声降解,当反应液体积为100 m L,超声40 min,随着CCl4添加浓度的增大（0-41.4mmol·L^-1）,环丙沙星的降解率由0.51%增至50.92%;荧光探针分析和异丙醇抑制结果表明增强作用主要在于·OH和一系列氯自由基的氧化;UPLC/MS/MS分析发现,降解过程中生成8种产物,其中包括3种氯代产物,环丙沙星按照6种途径进行降解。研究结果有助于深入研究CCl4增强超声降解抗生素的机理,提高过程处理效果。
