羟基

The Lewis acid sites M〓 on the surface of catalysts can chemisorb continuously gaseous molecule oxygen and transform it into lattice oxygen of the catalysts.

在反应过程中，有表面羟基形成，羟基相互作用形成H〓O，催化剂表面Lewis酸位M〓吸附气相中分子氧，并将其转化为晶格氧，使催化剂表面复原。

The invention is characterized in that the molecule of the polymer adsorption material has a structure in formula I: in the formula, R is selected from the natural polysaccharides with amino groups and hydroxyls and the derivatives thereof or the chemosynthetic polymers, the molecular weight of which is from 6 KD to 500 KD; X is selected from a C0 to C6 paraffinic chain with O atoms, N atoms or OH groups; R1, R2 and R3 are selected from a C1 to C4 alkyl group.

生物医学材料领域中的水溶性阳离子多聚物吸附材料及其应用，包括采用带有氨基或羟基的天然多糖及其衍生物或者化学合成多聚物季铵化反应合成，其特征在于该多聚物吸附材料分子具有式的结构：式中，R选自粘均分子量范围为6KD～500KD的带有氨基或羟基的天然多糖及其衍生物或者化学合成多聚物；X选自含有O原子、N原子或者OH基团的C 0 ～C 6 烷链；R 1 、R 2 、R 3 选自C 1 ～C 4 的烷基。

The free radical scavenging properties of six Aloe species are to be investigated in some modified chemical system. The antioxidant was purified by silica column and thin layer chromatography and analyzed by HPLC. A fraction was purified from A. brevifolia Mill showed the most effective scavenging activities on 〓 and ·OH (66. 01% and 38. 98% respectively). With the analysis of IR spectrum, UV spectrum and mass spectrum, the structure of FA was identifed as 8-C-D-glucopyranosyl-2- [2-hydroxy] propyl-5-methyl-7-hydroxychromone. Its scavenging activity on free radicals is higher than that of aloe-emodin. Its antioxidant activity may be due to the phenoxyl on glucosyl chromone which can be react with free radicals and form relatively stable free radicals.

本研究利用分别产生超氧阴离子自由基和羟自由基的化学模型体系研究比较了不同品种芦荟提取物的清除活性氧自由基的抗氧化作用，进一步利用硅胶柱结合薄层层析法和反相高压液相色谱法，从短叶芦荟叶子中首次分离了具有较强自由基清除能力（超氧阴离子自由基和羟自由基清除率分别为66.01％和38.98％）的成分FA，利用红外光谱、紫外光谱和质谱等仪器分析结果推断出该活性成分的分子结构为8-C-吡喃葡萄糖-2-[2-羟基]-丙基-5-甲基-7-羟基对氧萘酮，它的自由基清除能力高于芦荟大黄素，是一种天然抗氧化剂。

Single chain bolaamphiphile containing cinnamyl moiety [4-(ω-hydroxydecanyloxy)(ω-hydroxydecanyl) cinnamate, abr. HDC] was designed and synthesized.

制备了一种含肉桂酸基团的Bola型两亲分子HDC4-(10-羟基癸氧基-10-羟基癸氧基肉桂酸酯。

Supermolecular compounds with several hydroxyl groups, containing calix[4]arenes and cyclodextrins, are first used to crosslinking copolymerize with acrylic monomers.

首次使用含有多个羟基的大环超分子类化合物杯芳烃和环糊精分别与丙烯酸单体进行交联共聚，同时还引入了醇胺、肌醇和辛醇等含有羟基的小分子。

The soybean-protein fiber was developed by Li-Guanqi who is the member of the HuaKang group that is united with chemistry bioengineering in Pu Yang, HeNan province. The producer stuff of the soybean-protein fiber primarily contains beans dregs, hydroxyl and cyanic acid high polymer. Its production principle: First, soaking beans dregs into water and purifying out soybean-protein from the solution.

大豆蛋白改性纤维是由河南省濮阳华康化学生物工程联合集团公司李官奇等研制并生产的一种新型纺织纤维，它的主要生产原料是豆粕、羟基和氰基高聚物，其生产原理是将豆粕水浸分离提纯出蛋白质，将蛋白质改变空间结构并在适当的条件下与羟基和氰基高聚物共聚接枝，通湿法纺丝生成。

In the second part of the thesis, we discussed a L-proline-catalyzed direct Aldol reaction between L-amino acid-derived N,N-dibenzyl -amino aldehydes 15 and acetone, cyclopentanone or hydroxyacetone, which afforded (-amino--hydroxy- or (-amino-,(-dihydroxy-ketones in good to excellent yields (up to 94%) and diastereoseletivities (up to 94.9%).

发现许多情况下，反应的产率和de值超过90%。接着，在碱性条件下，我们将L-亮氨酸衍生的N，N-二苄基--氨基醛15g与羟基丙酮反应得到的主要产物(，-二羟基-γ-氨基酮171d与次溴酸钠反应，得到了具有抗肿瘤活性的天然产物PM-94128的氨基酸片断184。

The bacterial, mammalian and plant cytochrome P450s involved in metabolism of herbicides are reviewed in this paper. The action modes of cytochrome P450s on herbicides including dealkylation, ring-methyl hydroxylation and aromatic ring hydroxylation etc are summarized.

本文综述了代谢除草剂的细菌、哺乳动物和植物细胞色素P450酶系，概述了细胞色素P450酶系参与除草剂代谢的作用方式：脱烷基化作用、环甲基化羟基化作用和芳环的羟基化作用等。

A high proportion of 1,3- dihydroxy units were also formed in the acid-catalyzed hydrolysis of poly, however, hydrolysis of GIE generated only a 2,3-dihydroxy product.

有很大比例的1，3 -二羟基单位也形成酸催化水解聚，然而，旅游局水解生成只有2，3 -二羟基产品。

Optically active β,δ-dihydroxy esters have been widely used in the synthesis of natural products, polyol fragments, and chiral drugs.

具有光学活性的β，δ-二羟基酯已经在天然产品、多羟基化合物以及手性药物的合成中得到了广泛的运用。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。