By comparison of absorption spectra of quercetin in different medium, the influencing factors and possible mechanism of quercetin self-oxidation were investigated in this paper. The effects of self-oxidation of quercetin on its super anion free radical scavenging ability were also studied by the method of pyrogallol autoxidation. 通过比较槲皮素在不同介质中紫外吸收光谱变化,探讨槲皮素自氧化作用影响因素及可能机理,采用邻苯三酚自氧化法研究了槲皮素自氧化作用对其清除超氧阴离子自由基能力的影响。
The Ca2 + Fe2 + Fe3 + Cu2 + Mg2 +, etc. enhanced the self-oxidation of quercetin, and lowered the super oxygen-anion free radical scavenging ability of quercetin; 金属离子Ca2+、Fe2+、Fe3+、Cu2+、Mg2+等对槲皮素自氧化作用有增强效应,使槲皮素清除超氧阴离子自由基能力减弱,甚至出现负抑制;
Owing to high hardness and brittleness of SiC single crystal which has a good chemical stability, it is the critical issue that must be solved in its extensive application to obtain a wafer surface which is super smooth and free of scratch. 由于SiC单晶材料的硬度及脆性大,且化学稳定性好,故如何获得超平滑无损伤晶片表面已成为其广泛应用所必须解决的重要问题。
Investigation on the effects of quercetin self - oxidation on its super oxygen - anion free radical scavenging ability 槲皮素自氧化作用影响其超氧阴离子自由基清除能力的研究
This paper covers such important problems as earth connection, ups, super shielded transformer, earth free of power system and computer room, and methods to deal with them are also put forward. 介绍DCS和PLC供电系统设计和实践中关于接地、不间断电源、超隔离变压器、电源浮空和机房等几个主要问题及处理方法。