乙酸

Sodium diacetate,which is the molecular composite of sodium acetate and acetic acid,is a new type of multifunctional addition agent in foods and forages.

双乙酸钠是乙酸钠与乙酸分子的复合物，是一种新型的多功能食品及饲料添加剂。

Inthis papor,we synthesize and symbolize three sulphide bicarboxylate ligands such as 2.5-bis-1.3,4-thiadiazole;2,2 -(o-phenylenedimethylenethio) diacetic acid(L11); 2,2 -(m-phenylenedimethylenethio) diacetic acid.

本文合成和表征了2，2′-(1，3，4-噻二唑-2，5-二硫基)二乙酸、2，2′-邻苯二甲硫基二乙酸和2，2′-间苯二甲硫基二乙酸三个含硫二元羧酸配体。

The silk-protein-like polymers could be dissolved in hexafluroisopropanol and strong organic acid (e. g., formic acid, dichloroacetic acid and trifluroacetic acid), while they showed a poor solubility in common solvents.

所合成的模拟聚合物难溶于通常溶剂，但可以溶解在强酸溶剂（甲酸、二氯乙酸及三氟乙酸）和六氟异丙醇中；通过在二氯乙酸中25℃下的特性粘度测定而估算出聚合物的分子量在2～5万之间。

The result of study on the apparent kinetics of photochlorination of acetic acid showed that the reaction rate is comparatively slow and the byproduct of dichloroacetic acid is created during the reaction. In order to put the technology of photochlorination of acetic acid into industrialization, the new technology about distillation column with a single reactor having a large reactive potency must be adapted.

由乙酸光氯化反应宏观动力学研究结果可见，反应速度相对较慢，且生成二氯乙酸副产品，为了乙酸光氯化工艺实现工业化，必须采用具有较大反应能力的反应与精馏耦合工艺。

The reaction conditions of synthesizingcyclohexyl acetate catalyzed with ammonium ferric sulfate dodecahydrate NH4Fe(SO42.12H2Oare studied .The yield of cyclohexyl acetate can reach 87.2% under mole ratio of aceticacid,cyclohexyl alcohol and ammonium ferric sulfate is 1∶0.44∶0.02,cyclohexane as solvent ,refluxing and segregating water for 60min.

研究了NH4Fe(SO4)2.12H2O催化合成乙酸环己酯的反应条件，当乙酸、环己醇和硫酸铁铵的摩尔比为1∶0.44∶0.02，以环己烷为溶剂，回流分水60min，乙酸环己酯收率达87.2%，在相同反应条件下，合成了甲酸环己酯(收率为68.5%)、丙酸环己酯(收率为59.4%)和丁酸环己酯(收率为21.6%)。

The synthesis of sucrose ester containing ethanoyl and oleoyl was performed by transesterification between sucrose octaacetate and ethyi oleate in organic solvents, using lipases Novo435 as the catalyst.

在有机溶剂中，以脂肪酶Novo435为催化剂，蔗糖八乙酸酯与油酸乙酯通过转酯化反应合成了同时含有油酸酰基和乙酸酰基的混合型蔗糖酯，当蔗糖八乙酸酯与油酸乙酯的物质的量之比为1：1时，油酸乙酯的转化率达95％。

Ethyl 4,4,4-trifluoroacetoacetate was synthesized from ethyl acetate and 4,4,4-trifluoroacetate(mole ratio 3:1) with sodium ethoxide.

乙酸乙酯与三氟乙酸乙酯(摩尔比为3∶1)在乙醇钠作用下进行克莱森酯缩合反应，得到三氟乙酰乙酸乙酯。

Chapter 2 has analysized the conversly synthetic means of solanesol and designed novelly synthetic routes of solanesol and key intermediate Chapter 3 has summarized the preparation of trans-3-methyl-4-hydroxy (bromo-2-butenyl oxy methyl benzene In chapter 4 ,a novel technology of important intermediate(all trans-8-bromo geranyl acetate),which is suitable for industrial procedure , was found .meanwhile,an another new way has been invented ,of which the key intermediate (all trans-8-hydroxy geranyl acetate) has been produced.

第二部分分析了茄尼醇的逆合成方法，设计了一条适合于合成茄尼醇的合成路线及其重要中间体的合成路线。第三部分研究了重要中间体[Trans-3-甲基-4-羟基-2-丁烯基乙酰基(苄基，2，3-二氢吡喃基)醚]的合成新方法，找到了一条适合于工业化生产的制备反式-3-甲基-4-羟基-2-丁烯基苄基醚的新方法。第四部分研究了重要中间体[-3，7-二甲基-8-羟基-2，6-辛二烯-1-醇乙酸酯、-3，7-二甲基-8-溴-2，6-辛二烯-1-醇乙酸酯]的合成新方法，找到了一条适合于工业化生产的制备它们的新方法；同时研究了一条制备-3，7-二甲基-8-羟基-2，6-辛二烯-1-醇乙酸酯的另一新方法。

The review highlights the technical developments in the identification,quantification and separation of α-hydroxyacetic acid,especially solvent extraction and synergistic extraction.

文章比较了各种羟基乙酸定性及定量分析方法，综述了羟基乙酸分离方法，特别是溶剂萃取和协同萃取效应。最后，分析了羟基乙酸的开发前景。

The advantages of α-hydroxyacetic acid biosynthesis over traditional chemical conversion are wide range of reaction condition,high conversion ratio and green process.

化学法生产羟基乙酸存在原料消耗大、产品收率低、环境污染严重等缺点；生物法合成羟基乙酸条件温和、底物转化率高，为绿色合成羟基乙酸提供强有力的技术支持。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。