查询词典 acetic aldehyde

Vanillin 58 was used as starting material, which underwent methylation, bromination, acetalization, lithiation followed by nucleophlic addition to aldehyde, Diels-Alder reaction, selective reduction and lactonization to produce diphyllin in an overall yield of 38%(7 steps).

这个方法从香兰素58开始，经过甲基化、溴化、成乙二醇缩醛反应、锂化而后对醛亲核加成、Diels-Alder反应、选择性还原反应和内酯化反应共7步，最后得到diphyllin，总产率38％。

The synthesis of celery ketone from butyl aldehyde and ethyl acetoacetate was improved with higher yield by using solid superbase(K2O/γ-Al2O3) for the first time.

在正丁醛和乙酰乙酸乙酯为原料合成芹菜酮的合成过程中，对其催化方法进行改进。

METHODS Acetylacetone, 4－Dimethylaminobenzaldehyd and alcohol without aldehyde were used as color reagents. The determination method was colorimetry.

以乙酰丙酮、无醛乙醇和对二甲氨基苯甲醛溶液为显色剂，用比色法测定。

Various synthetic method of 1,3-propanediol were introduced and compared, including hydration and hydrogenation of acrylaldehyde, carbonylation of epoxy ethane , microbiological fementation, the process starting from methyl aldehyde, etc.

介绍了1，3-丙二醇的几种制备方法，即丙烯醛水合-氢化法、环氧乙烷羰基化法、微生物发酵法和以甲醛等为原料的方法。

The research results indicated that the first cross-linking between the HPAM and Cr3+ in ground condition was propitious to reduce leaking of blocking agent in oil layer, and the second crosslink action between acylamino of HPAM and organic phenolic aldehyde can form the high intensity gel and it can endure high temperature.

研究结果表明，HPAM羧基与Cr~(3+)离子在地面条件下的一次交联作用有利于减少堵剂在油层的漏失量，HPAM酰胺基与有机酚醛在地层条件下的二次交联作用，能够形成耐温高强度凝胶。

The categorical names are often combined, with a six-carbon-atom aldehyde sugar being termed AN aldohexose.

它们的命名经常被结合起来，一个六个碳原子的醛糖被称为已醛糖。

Glucose an aldohexose, exists as D and L forms. The furthest asymmetric carbon from the aldehyde group is C-5. D-glucose is called D because the configuration of the atoms bonded to C-5 is the same as for D-gly- ceraldehyde. Similarly D-fructose﹙a ketohexose﹚ is designated D because the configuration

环状结构：醛基或酮基跟一个羟基反应共价闭合，形式上一个糖的醛基和羟基反应生成了一个半缩醛，而一个酮基与一个羟基反应生成一个半缩酮，在同一分子内这个反应能进行，单糖的开链式形成了糖环，葡萄糖环形成一个六碳环。

4R,5S,6R-5,6-Bis-allyl-6-aldehyde-γ-hexanelactone I-145 was prepared from D-arabinose by six steps. Compound I-145 underwent Mukaiyama-type intramolecular aldolization to produce bicyclooctane I-147 stereospecifically.

我们以D-阿拉伯糖为起始原料，经六步反应，得到(4R，5S，6R)-5， 6-二烯丙氧基-6-醛基-γ-己酸内酯I-145，然后I-145发生分子内的Mukaiyama式aldol缩合反应，完全立体专一性地得到环化中间体I-147。

The results showed: With the aggravation of salinization and alkalization, content of betaine and activity of betaine aldehyde dehydrogenase increased.

结果表明：甜菜碱含量和甜菜碱醛脱氢酶活性随着土壤盐碱化程度的加重而增加。

Six, which was the most serious in salinization and alkalization, content of betaine arid activity of betaine aldehyde dehydrogenase of Leymus chinensis were the highest.

在盐碱化程度最重的6号样地羊草叶片中积累了较高含量的甜菜碱可能是羊草耐受盐碱胁迫的主要原因之一。

The shaping method of noncircular part and the tool holder's radial motion characters in noncircular turning process are discussed in detail in the thesis.

论文详细研究了非圆零件的成型方法和加工过程中刀架的径向运动规律。

I have not really liked him,I do not like his this kind of disposition.

我没有真的喜欢他，我不喜欢他的这种性格。