查询词典 condensation

Based on the power series expansion of the general flexible matrix of the sub-system, a general expression of the dynamic stiffness matrix of the reduced model was derived from the exact expression of the reduced model for the direct substitution dynamic condensation methods. The general expression was also expressed as a power series of the unknown eigenvalues. After that, the validity and error of the Guyan condensation method were analyzed.

对于动力缩聚直接代入法，本文从降阶模型的精确表达式出发，利用子系统广义柔度矩阵的幂级数展开式，导出了降阶模型动刚度矩阵的一般表达，并把它表示为未知特征值的幂级数形式，在此基础上对 Guyan缩聚法的适用范围和误差进行了一般分析。

Master the Keto-Enol tautomerism; reactions of enols:α-H substitution reactions;α-halogenation of aldehydes and ketones;α-bromination of carboxylic acids; acidity ofα-H atoms: enolate ion formation; reactivity of enolate ions; alkylation of enolate ions; mechanism of carbonyl condensation reactions;condensations of aldehydes and ketones: the Aldol reaction; dehydration of Aldol products; the Claisen condensation reaction; the Michael addition.

熟练掌握酮式－烯醇式互变异构；烯醇的反应：α-H的活性；醛酮的α卤代反应；羧酸的α-溴代反应；α-H的酸性：烯醇负离子的形成；烯醇负离子的反应；烯醇负离子的烃基化；羰基化合物的缩合反应机理；醛酮的缩合反应－Aldol缩合；Aldol缩合产物的脱水反应； Cleisen 酯缩合反应；麦克尔加成反应。

Methods starting from dimethyl succinate and benzaldehyde, mitiglinide calcium was obtained via 7 chain steps including stobble condensation, hydrolization, anhydration, condensation with cis-hexahydroisoindoline, reduction, separation, salt formation.

方法以丁二酸二甲酯和苯甲醛为原料，经stobble缩合、水解、脱水，与顺-全氢异吲哚缩合后经还原、拆分、成盐等7步反应制得糖尿病治疗药物米格列奈钙。

Ethoxycarbonyl-4,5-dimethyl-pyrrole (7) was prepared from ethylacetoacetate, ethyl formate and methyl ethyl ketone via oximination, Claisen condensation, and reductive condensation. The bromization of compound 7 gave 2-ethoxycarbonyl-3-bromo-4,5-dimethyl-pyrrole(8), which could be transferred to 2-ethoxy-carbonyl-3-brome-4-methyl-5-formyl-pyrrole (9) by the formolation.

由乙酰乙酸乙酯、甲酸乙酯及丁酮等原料经过肟化、Claisen缩合、还原缩合成环得到2-乙氧羰基－4，5-二甲基－吡咯(7)，溴化生成2-乙氧羰基－3-溴4，5-二甲基－吡咯(8)，最后经过甲酰化反应得到目标产物2-乙氧羰基－3-溴－4-甲基－5-甲酰基－吡咯(9)。

Secondly, the flow of condensation steam was compared with the flow of ideal gas. From the contrasted results, it can be found the difference between the condensative steam flowing and ideal-gas flowing. And, it also can be found out that it is inevitable to condense for steam flowing under the supersonic state. At the same time, the major areas which formed second drips have been displayed in the solved results. Finally, the flow of condensation steam in the 3-dimension model has been simulated.

其次，对比了具有凝结的蒸汽与理想气体之间的流动情况，经过对比可以发现凝结蒸汽在流动中与理想气体之间的差异，发现蒸汽的凝结在超音速状态下是不可避免的，并且在计算结果中通过图形显示出了形成二次水滴的主要区域。

Firstly, 3-ethylthiobutanal was prepared from crotonaldehyde reacting with ethanehiol in triethylamine with high yield. Secondly, methyl acetoacetate was converted to 6-ethylthiohept-3-en-2-one by three steps via hydrolysis, condensation with 3-ethyltio-butanal and dehydration, then 6-ethylthiohept-3-en-2-one was cycloco ndensed with dimethyl malonate by Michael addition and Claisen condensation, followed by saponification and decarboxylation to give the intermediate of 5-(2-ethylthiopropyl)-cyclohexane-1,3-dione.

首先，以巴豆醛与乙硫醇为原料，在三乙胺的催化作用下高收率制得3-乙硫基丁醛；然后从乙酰乙酸甲酯出发，通过碱水解、与3-乙硫基丁醛缩合、脱水三步反应合成6-乙硫基-3-烯-2-庚酮，接着6-乙硫基-3-烯-2-庚酮与丙二酸二甲酯通过Michael加成和Claisen缩合成环，再通过皂化和脱羧反应生成中间体5-[2-丙基]-1，3-环己二酮；再与丙酸酐反应丙酰化，最后与0-3-氯-2-丙烯基羟胺肟化，得到目标化合物烯草酮。

The condensation of aromatic aldehydes with active methylene compounds like malononitrile, cyanoacetamide and ethyl cyanoacetate has been found to proceed very efficiently at room temperature giving excellent yields, but the condensation of heteroaromatic,α,β-unsaturated and aliphatic aldehydes with active methylene compounds proceeded smoothly in 50~65℃ with good yields and the reactions of aromatic, aliphatic ketones as well as p-phthalaldehyde with malononitrile also proceeded in 75~85℃ with moderate yields.

芳香醛与活泼亚甲基化合物如丙二腈、氰基乙酸乙酯、氰基乙酰胺的缩合在室温下即能顺利进行，获得了很高的收率；而对于杂环芳醛、α，β-不饱和的醛以及脂肪醛与活泼亚甲基化合物的缩合，需在50~65℃下进行，也取得了很高的收率；对于脂肪酮、芳香酮以及二元醛与丙二腈的缩合在75~85℃下也能顺利地进行，获得中等以上的收率。

Co condensation type polyamides were prepared by using 1,2 dihydro 2 (4 aminophenyl) 4 [4 (4 aminophenoxyl) phenyl] phthalazin 1 one and 4,4′ diamino biphenyl ether or 4,4′ diamino biphenyl methane as the co diamine monomers and aromatic diacid as the co condensation monomer.

采用 1 ，2 -二氢-2 -( 4-氨基苯基)-4 -[4 -( 4-氨基苯氧基)-苯基 ]-二氮杂萘-1 -酮、4 ，4′-二氨基二苯醚、4 ，4′-二氨基二苯甲烷为共缩聚二胺单体与对苯二甲酸进行共缩聚反应，制备共缩聚型聚酰胺。

In the process of dropwise condensation, small droplets grow by direct condensation and large ones grow by coalescence.

在滴状冷凝过程中，较小的液滴主要靠直接冷凝长大，较大的液滴主要由合并产生。

Through the study of the effect of contact angle on heat transfer in dropwise condensation, it has been demonstrated that an optimum contact angle in dropwise condensation exists from the view of heat transfer.

通过接触角对滴状冷凝传热影响的理论研究，从传热学角度证明了滴状冷凝过程中最佳接触角的存在。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。