助手标题  
全文文献 工具书 数字 学术定义 翻译助手 学术趋势 更多
查询帮助
意见反馈
   (esterification) 的翻译结果: 查询用时:0.01秒
图标索引 在分类学科中查询
所有学科
有机化工
更多类别查询

图标索引 历史查询
 

esterification
相关语句
  相似匹配句对
     Study on the esterification
     酯化反应的探讨
短句来源
     On Esterification and Decolorizing of the
     黄水的酯化与脱色处理
短句来源
查询“(esterification)”译词为用户自定义的双语例句

    我想查看译文中含有:的双语例句
例句
为了更好的帮助您理解掌握查询词或其译词在地道英语中的实际用法,我们为您准备了出自英文原文的大量英语例句,供您参考。
  esterification
Rosin glycerin ester and its bromide were prepared from natural renewable rosin, glycerin and liquid bromine which were first subjected to an esterification reaction, followed by an addition reaction.
      
The catalytic activities of the solid acids were evaluated by esterification of acetic acid and butanol and the results were compared with those catalysts prepared at normal conditions.
      
Results show that PEG400 can be grafted onto the surface of the films via esterification with SMA.
      
Dimethyl 4,6-bis(bromomethyl) isophthalate was synthesized by bromomethylation, oxidation, esterification and bromination of 1,3-dimethylbenzene.
      
These substances are products of enzymatic esterification of sugars followed by their dehydration by heat treatment or long seasoning of grape wines.
      
更多          


As a model experiment for the synthesis of A, B rings of tetracyclines, thesynthesis of 9-hydroxydecalin-1, 3-dione (VIII) is reported. Ethyl 2-ethynyl-2-hydroxycyclohexaneacetate (III), b. p. 105--7°/0.1mm, and its corresponding acid(IV), m. p. 100--1°, were obtained by the ethynylation of ethyl cyclohexanone-2-acetate (II). Hydration of III, followed by hydrolysis, gave 2-acetyl-2-hydroxycyclohexaneacetic acid (V), m. p. 115--7°. which on esterification withdiazomethane yielded its methyl ester (VI),...

As a model experiment for the synthesis of A, B rings of tetracyclines, thesynthesis of 9-hydroxydecalin-1, 3-dione (VIII) is reported. Ethyl 2-ethynyl-2-hydroxycyclohexaneacetate (III), b. p. 105--7°/0.1mm, and its corresponding acid(IV), m. p. 100--1°, were obtained by the ethynylation of ethyl cyclohexanone-2-acetate (II). Hydration of III, followed by hydrolysis, gave 2-acetyl-2-hydroxycyclohexaneacetic acid (V), m. p. 115--7°. which on esterification withdiazomethane yielded its methyl ester (VI), m. p. 37--8°. The latter was cyclizedby sodium methoxide to form 9-hydroxydecalin-1, 3-dione (VIII), m. p. 182--3°,which showed characteristic concentration-dependent ultraviolet absorptionspectra of cyclic 1, 3-diketones. On treatment with concentrated hydrochloricacid or methanolic HCl, VIII gave 1, 3-dihydroxy-5, 6, 7, 8-tetrahydronaphthalene(IX) or 1, 3-dimethoxy-5, 6, 7, 8-tetrahydr (X) respectively. On the basis of the stability of the two γ-hydroxy acids, IV and V, andthe difficulty of lactonization of the latter, cis fusion of the two rings incompound VIII is assigned.

本文报告四圜素类抗生素A,B环的模型化合物9-羟基十氢萘-1,3-二酮(Ⅷ)的合成。Ⅱ起乙炔基化反应後,得到Ⅲ与Ⅳ。Ⅲ先经水化反应,继以水解,产生V。V与重氮甲烷作用生成Ⅳ,後者用无醇甲氧钠处理即环化而成Ⅷ。Ⅷ经浓盐酸脱水生成Ⅸ,经甲醇氯化氢处理生成Ⅹ。并推测Ⅷ的二个环是顺位相联接。

Although esterification reaction betweea monobasic acids and mouohydric alcohols is a well-known chemical reaction,on which various authors,such as Goldschmidt,Hinshelwood,Flory and others,have done much work,but the mechanism of esterification and the order of the reaction in the absence or presence of a foreign acid remain unclarified.For this purpose we have studied the kineties of esterification reactions between laurie acid and normal octyl alcohol with equi-or non-eqnimolar quantity ratios...

Although esterification reaction betweea monobasic acids and mouohydric alcohols is a well-known chemical reaction,on which various authors,such as Goldschmidt,Hinshelwood,Flory and others,have done much work,but the mechanism of esterification and the order of the reaction in the absence or presence of a foreign acid remain unclarified.For this purpose we have studied the kineties of esterification reactions between laurie acid and normal octyl alcohol with equi-or non-eqnimolar quantity ratios in the absence or presence of a foreign acid at different temperatures.According to our experimental data,we propose the following mechanism for the esterification reaction between monobasic acids and monohydri calcohols:

本文建议一种新的酯化反应的氢离子催化机构,这机构与公认的酯化反应的氢离子催化机构的区别在于氢离子的来源和氢离子参与反应的详细历程,肯定氢离子不仅由外酸供给,而且也可由单元酸本身电离得来,另外,单元酸和单元醇都可作为氢离子的载体。酯化反应的功力学方程与单元酸和单元醇起始的克分子比有密切关系,应由(3)式表示。当酸与醇以等克分子比起反应,在无外酸作催化剂时,酯化反应是2(1/2)级反应;若有外酸作催化剂,当外酸的量加得适当多,由单元酸本身供给的氢离子的贡献可以忽略时,是二级反应;当外酸的量加得少,由单元酸本身供给的氢离子的贡献不可以忽略时,它不再是二级反应。当酸与醇以不等克分子比起反应,动力学方程比较复杂,实验结果亦与理论相一致。这样,我们用同一反应机构解释所有不同克分子比的单元酸与单元醇的酯化反应的实验数据。

Much experimental studies on the polyesterification reactions between dibasic acids and glycols have been reported by various authors,among them Menshytkir,Dostal and Raff,Flory,Rafikov and Korshak,Davies,Colonge and Stuchlik,and others,but quite diversed results were obtained.According to Flory,polyesterification in the absence of a foreign acid,owing to catalytic effect of the dibasic acid molecule,is a third-order reaction.Other authors pointed out that,polyesterification should be a bimolecular reaction...

Much experimental studies on the polyesterification reactions between dibasic acids and glycols have been reported by various authors,among them Menshytkir,Dostal and Raff,Flory,Rafikov and Korshak,Davies,Colonge and Stuchlik,and others,but quite diversed results were obtained.According to Flory,polyesterification in the absence of a foreign acid,owing to catalytic effect of the dibasic acid molecule,is a third-order reaction.Other authors pointed out that,polyesterification should be a bimolecular reaction of second-order,or second-order in the early stage and third-order in the later stage of the reac- tion.In this work,we attempted to show that,polyesterification between dibasic acid and glycol is as well as esterification between monoacid and monoalcohol,provoked by the catalysis of hydrogen-ion.When the dibasic acid and the glycol react in equi-molar quantity ratio in the absence of a foreign acid,the hydrogen-ions come from the ionization of the dibasic acid itself,and in consequence the concentration of hydrogen-ion is proportional to the square root of the concentration of the dibasic acid,polyesterification is a 2~1/_2-order reaction.On the other hand,in the presence of a foreign acid,the order of reacton varied continuously from one extreme ease of 2~1/_2-order to another extreme case of second order according to whether the concentration of hydrogen ion derived from the foreign acid or the dibasic acid may be neglected.All our experimental results of polyesterification reactions either between sebacic acid and ethylene glycol,sebacic acid and diethylene glycol,adipic acid and hexamethylene glycol,and sebacic acid and hexamethylene glycol in the absence of foreign acid at different temperatures,or between adipic acid and ethylene glycol in the presence 0.41,0.82,1.23,2.05,4.10 and 12.30.10~(-3) mole of sulfuric acid per kilogram as catalyst at 140℃,are in good agreement with this proposed mechanism.Data of other authors were re-examined on the basis of our proposed mechanism of hydrogen ion catalysis in esterification and were all found to conform to the 2~1/_2-order relationship.Thus,the views by earlier workers that polyesterification is catalyzed by the dibasic acid molecule itself or that it is a simple second-order reaction,or a second-order in the early stage and a third-order in the later stage of the reaction,all are refuted and the long disputed question of the order of polyesterification is assumed to be clarified.

聚酯反应象单元酸与单元醇的酯化反应一样,都是氢离子催化机构。这种机构与现在公认的聚酯反应的氢离子催化机构的区别在于氢离子的来源和氢离子参与反应的详细历程,肯定了氢离子不仅由外酸供给,而且也可由二元酸本身供给。另外,二元酸与二元醇均可作为氢离子的载体。聚酯反应的动力学方程与二元酸与二元醇的起始克分子比有密切关系,应由前篇(3)式表示。当酸与醇以等克分子比起反应,又无外酸存在时,聚酯反应是2(1/2)级反应;若有外酸作催化剂时,当外酸的量加得适当多,由二元酸本身供给的氢离子的贡献可以忽略时,是二级反应,与以往结论相一致:当外酸的量加得少,必须考虑氢离子的同离子效应,它就不再是简单的二级反应,当酸与醇以不等克分子比起反应我们的实验结果亦与理论一致。

 
<< 更多相关文摘    
图标索引 相关查询

 


 
CNKI小工具
在英文学术搜索中查有关(esterification)的内容
在知识搜索中查有关(esterification)的内容
在数字搜索中查有关(esterification)的内容
在概念知识元中查有关(esterification)的内容
在学术趋势中查有关(esterification)的内容
 
 

CNKI主页设CNKI翻译助手为主页 | 收藏CNKI翻译助手 | 广告服务 | 英文学术搜索
版权图标  2008 CNKI-中国知网
京ICP证040431号 互联网出版许可证 新出网证(京)字008号
北京市公安局海淀分局 备案号:110 1081725
版权图标 2008中国知网(cnki) 中国学术期刊(光盘版)电子杂志社