酰氧基

The preparation of potassium malonyloxyborohydride in situ and its seletive hydroborating alkene are described.

介绍了丙二酰氧基硼氢化钾的制备及其原位与烯烃的选择性硼氢化。

Amino desacetoxycephalosporanic acid (7 - ADCA) is an ampholyte.

7-氨基去乙酰氧基头孢霉烷酸是两性化合物，从等电点两侧改变溶液的 p H值都可以产生过饱和度并结晶得到晶体产品，本文对 7-ADCA两种方法结晶的初级成核过程进行了研究。

In this paper the surface charge density of cationic kraft pulp was chosen as response variable and the preparation conditions of cationic kraft pulp by the in-situ grafting copolymeration of acrylamide and cationic monomer, [2- ethyl] trimethyl-ammonium chloride were optimized by central composite design.

摘 要：以阳离子硫酸盐浆的表面电荷密度为评价指标，采用中心复合设计法对丙烯酰胺和甲基丙烯酰氧基乙基三甲基氯化铵接枝共聚制备阳离子硫酸盐浆的工艺进行了优化。

Aim To study the biocompatibility of Dacron vascular prosthesis surface in rabbit model coated with 2-methacryloyloxyethyl phosphorylcholine by ozonization.

目的 通过臭氧活化的方法在涤纶人工血管表面接枝2-甲基丙稀酰氧基乙基磷酰胆碱，进行接枝后人工血管血液相容性研究。

In a system consisting of 20% PEG 400 and 12% magnesium sulfate, the partition coefficient of PGA was less than 0.01, PGA almost completely partitioned into the magnesium sulfate-rich bottom phase. Meanwhile, the partition coefficient of cephalexin was 6.7, the partition coefficients of phenylglycine methyl ester and 7-ADCA were 1.5 and 1.2, respectively.

通过考察头孢氨苄、苯甘氨酸甲酯和7-氨基脱乙酰氧基头孢烷酸(7-ADCA)在ATPS中的分配行为建立了一个含20%PEG 400和12%硫酸镁的ATPS，在此体系中头孢氨苄的分配系数为6.7，苯甘氨酸甲酯的分配系数为1.5，7-ADCA的分配系数为1.2，且青霉素酰化酶的分配系数小於0.01。

Synthesis and characterization of (3-acyloxy-2-hydroxy)propyl-β-cyclodextrin.

酰氧基-2-羟丙基-β-环糊精的合成与表征。

The first asymmetric synthesis of trans-β-hydroxy-γ-butyrolactones:-(3R, 4R, 5S)-4-(1-acetoxy-isopropyl)-3-hydroxy-butyrolactone 65a was achieved starting from isobutylaldehyde through nine steps. The key steps involve the construction of three chiral carbon centers by the Sharpless's asymmetric epoxidation and Substrate directable chemical reaction.

以异丁醛为起始原料，经过九步反应首次设计合成了具有三个手性中心的trans-β-羟基-γ-丁内酯：-（3R，4〓，5S）-4-（1-乙酰氧基-异丙基）-3-羟基-丁内酯65a，关键步骤是Sharpless不对称环氧化和底物定向不对称合成反应。

The wholly aromatic four-component copolyesters were prepared from p-acetoxy-benzoic acid, hydroquinone diacetate, 2,6-naphthalene dicarboxylic acid and isophthalic acid by melting polycondensation.

由对乙酰氧基苯甲酸、对苯二酚二乙酯、2，6-萘二甲酸及间苯二甲酸四种单体通过熔融缩聚反应，合成了全芳香族四组分共聚酯。

Deoxybenzoin(3) was prepareded by using the resorcinol and substituted phenylacetic as starting meterials in microwave-mediated.Then the compound(3) was reacted with acetic anhydride to produce(4).The compound(4) was hydrolyzed to convert compound(5) in the acid-mediated. The compound(5) was reacted with the 1,2-dibromo-ethane and 1,3-dibromo-propane in refluxed condition with acetone as solvent to give(6) or(7),respectively.Lastly,the title compounds were synthesized by refluxing(6) or(7) with 2-methyl-benzimidazole and potassium carbonate in acetone solution.

以取代苯乙酸和间苯二酚为起始原料，用微波辐射法合成脱氧安息香(3)，(3)与乙酸酐缩合生成2-甲基-7-乙酰氧基异黄酮(4)，(4)在酸性条件下水解生成相应的异黄酮(5)，化合物(5)分别与1，2-二溴乙烷和1，3-二溴丙烷反应生成(6)和(7)，化合物(6)和(7)再分别与2-甲基苯并咪唑偶合生成目标化合物。

Finally, we discuss the preparation, characterization and application of alkylsilane and mercaptoacetoxy monolayers on ordered mesoporous titanosilicate molecular sieve.

最后，我们讨论了介孔钛硅分子筛表面烷基硅烷单层和巯基乙酰氧基单层的制备、表征及应用。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。