查询词典 free radical

DPPH method, pyrogallol method and Fenton reaction were used to study the scavenging ability of extracts with 95% ethanol, ethyl acetate, acetone, acetic acid, chloroform, methanol to free radical activity.

方法］应用DPPH法、邻苯三酚自氧化法和Fenton反应分别研究了浓度95%乙醇、乙酸乙酯、丙酮、乙酸、氯仿、甲醇提取物清除自由基活性的能力。

The latter is chlorinated in the side chains under free-radical conditions to give 2,4-dichloro-5-fluoro-3-dichloromethyl-1-trichloromethylbenzene. The latter is hydrolysed via 2,4-dichloro-5-fluoro-3-dichloromethylbenzoic acid, which can be isolated if necessary, to give 2,4-dichloro-5-fluoro-3-formyl-benzoic acid, the aldehyde group of which is reacted to give 2,4-dichloro-5-fluoro-3-N-hydroxyiminomethyl-benzoic acid, from which, with simultaneous conversion of the carboxyl group into the chlorocarbonyl group, water is eliminated using an acid chloride to give the nitrile 2,4-dichloro-3-cyano-5-fluoro-benzoyl chloride.

随后，在游离基条件下进行侧链的氯化，得到2，4-二氯-5-氟-3-二氯甲基-1-三氯甲基苯、后者被水解，经过2，4-二氯-5-氟-3-二氯甲基苯甲酸(如果需要此化合物可以分离)，得到2，4-二氯-5-氟-3-甲酰苯甲酸，将其醛基反应，得到2，4-二氯-5-氟-3-N-羟基亚氨基甲基苯甲酸，用酰氯从其中除去水，同时将羧基转化为碳酰氯，得到一种腈，即2，4-二氯-3-氰基-5-氯-苯甲酰氯。

Antioxidative activity of flavonoids from Lespedeza bicolor were investigated by examining the scavenging effects on hydroxyl radicals and superoxide anion O2(superscript - and the inhibitions on auto-oxidation of lard, rape seed oil, and linoleic acid, The results showed that LBF had significant scavenging functions to free radical and superoxide anion, and the scavenging effect increased with the increase of the content of LBF; LEF can remarkably inhibit auto-oxidation of lard, rape seed oil, and linoleic acid, indicating its potential as a natural antioxidant.

通过二色胡枝子黄酮(Lespedeza bicolor flavonoids， LBF)清除羟自由基、超氧阴离子的效果及抑制猪油、菜油、和亚油酸的自氧化来研究二色胡枝子黄酮的抗氧化活性。其研究结果表明，二色胡枝子黄酮对清除自由基有显著性作用，且清除率随黄酮浓度的增加而增大；能够极显著地抑制猪油、菜油、亚油酸的自氧化(P.01)，抑制作用随浓度的增大而增强。作为天然的抗氧化剂，二色胡枝子黄酮具有一定的开发利用价值。

Young Barley Grass Powder is abundant of valued antioxidant properties known as PRE-SOD or SOD-LIKE enzymes that helps elimination of free radical from the body.

大麦苗当中最宝贵的成分，是它丰富的抗氧化酵素。而其中被称为Pre-SOD或SOD-like的酵素，协助人体消除自由基。

To study the mechanism of free radical's lessening and preventing the injury of the body tissues and its anti-fatigue action in the exhausted rats taking bee milk.

江苏大学体育部，江苏镇江 212001摘要：探讨服用蜂王浆的大鼠，作力竭运动时，减轻和防止自由基对机体组织的损伤和抗疲劳作用。

The process includes the following steps: dissolving bromine in halogenated hydrocarbon, dropping the bromine solution into reactant system comprising pentabromo toluene, halogenated hydrocarbon, free radical initiator and hydrogen peroxide at 50-65 deg.c, and heating to 60-78 deg.c for reflux reaction until the reactant system becomes transparent; filtering the resultant to obtain solid product, washing with carbon tetrachloride and water separately and vacuum drying to obtain pentabromo benzyl bromide.

具体步骤为：将五溴甲苯、卤代烃、自由基引发剂和过氧化氢组成的反应体系加入到三颈瓶中，将0.07～0.1mol的溴溶于50ml卤代烃配成溶液，在50-65℃温度下滴加到反应体系中，滴加时间为50-70分钟，然后升温至60-78℃温度下回流反应，至反应体系逐渐变透明，且不再产生气泡时，将所得产物过滤，得到固体产物，分别用CCl 4 和水洗涤，真空干燥，即得到五溴苄基溴；其中，五溴甲苯与溴的摩尔比为1∶0.7-1∶1.0，溴与过氧化氢的摩尔比为1∶1.0-1∶1.4，自由基引发剂加入量为五溴甲苯重量的1-10％，卤代烃的加入量为反应体系体积的40％-100％，所用溶剂可以直接进行下一批反应，不需要更换溶剂或蒸馏提纯。

The carbon tube ubstituted by benzyl chloride which is manufactured in the invention can adopt free radical addition reaction.

在本发明中制备苄基氯取代的碳管可以采用自由基加成反应。

The team found that human liver Beta carotene can be decomposed into vitamin A, has orange carrot to such ingredients can also effective against free radical damage.

该研究小组发现，人类的肝脏可将贝塔胡萝卜素分解成维生素A，这类让萝卜呈现橙色的成分也能有效对抗自由基的破坏。

The polypropylene used for making cigarette filters was prepared with the process of free radical graft copolymerization in order to raise the selfadhesive power and surface energy of the PP.

用自由基化学接枝共聚的方法制作聚丙烯香烟滤材，以提高其表面能，增加自粘性。

To use corresponding antagonist or free radical cleaner could effectively protect brain cell, relieve cerebral edema and head injury.

可采用相应的拮抗剂或自由基清除剂能有效地保护脑细胞，减轻脑水肿，显著降低颅脑损伤。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。