采用邻二氮菲比色法测定Fenton反应产生的.OH,确定了最佳实验条件为pH为7.4的磷酸盐缓冲溶液,Fe2+、H2O2及邻二氮菲的浓度分别为0.4 mmol/L、0.015%及0.35 mmol/L,37℃水浴加热90 m in.并用抗坏血酸及硫脲验证了方法的可靠性.在上述条...采用邻二氮菲比色法测定Fenton反应产生的.OH,确定了最佳实验条件为pH为7.4的磷酸盐缓冲溶液,Fe2+、H2O2及邻二氮菲的浓度分别为0.4 mmol/L、0.015%及0.35 mmol/L,37℃水浴加热90 m in.并用抗坏血酸及硫脲验证了方法的可靠性.在上述条件下利用怀山药提取液测定了其抗羟自由基活性,结果较为满意,表明该体系可作为筛选抗氧化剂的方法之一.展开更多
The complex of Sm2(o-NBA)6(PHEN)2 (o-NBA, o-Nitrobenzoate; PHEN, 1,10-phenanthroline) was prepar-ed and characterized by elemental analysis, IR and UV spectraoscopy. The thermal decomposition mechanism of Sm2(o-NBA)6(...The complex of Sm2(o-NBA)6(PHEN)2 (o-NBA, o-Nitrobenzoate; PHEN, 1,10-phenanthroline) was prepar-ed and characterized by elemental analysis, IR and UV spectraoscopy. The thermal decomposition mechanism of Sm2(o-NBA)6(PHEN)2 was studied under a static air atmosphere by TG-DTG. The thermal decomposition kinetics of the complex for the first stage was studied under non-isothermal condition. The most probable mechanism functions of the thermal decomposition reaction for the first stage are: G(α)=[-ln(1-α)]1/2, f(α)=2(1-α)[-ln(1-α)]1/2. The activation energy E for the first stage is 259.50 kJ·mol-1, the pre-exponential factor A is 36.19×1018 min-1. The lifetime equation at weight-loss of 10% was deduced as lnτ=-36.70+27 572.12/T by isothermal thermogravimetric analysis.展开更多
文摘采用邻二氮菲比色法测定Fenton反应产生的.OH,确定了最佳实验条件为pH为7.4的磷酸盐缓冲溶液,Fe2+、H2O2及邻二氮菲的浓度分别为0.4 mmol/L、0.015%及0.35 mmol/L,37℃水浴加热90 m in.并用抗坏血酸及硫脲验证了方法的可靠性.在上述条件下利用怀山药提取液测定了其抗羟自由基活性,结果较为满意,表明该体系可作为筛选抗氧化剂的方法之一.
文摘The complex of Sm2(o-NBA)6(PHEN)2 (o-NBA, o-Nitrobenzoate; PHEN, 1,10-phenanthroline) was prepar-ed and characterized by elemental analysis, IR and UV spectraoscopy. The thermal decomposition mechanism of Sm2(o-NBA)6(PHEN)2 was studied under a static air atmosphere by TG-DTG. The thermal decomposition kinetics of the complex for the first stage was studied under non-isothermal condition. The most probable mechanism functions of the thermal decomposition reaction for the first stage are: G(α)=[-ln(1-α)]1/2, f(α)=2(1-α)[-ln(1-α)]1/2. The activation energy E for the first stage is 259.50 kJ·mol-1, the pre-exponential factor A is 36.19×1018 min-1. The lifetime equation at weight-loss of 10% was deduced as lnτ=-36.70+27 572.12/T by isothermal thermogravimetric analysis.