查询词典 crotonaldehyde

Thermoelectric resources to accelerate its comprehensive development and utilization of sea Huangqiao thermoelectric Limited and Taixing Huang Cement Manufacturing Co., Ltd. will carry out extensive market research on the basis on September 9, 2005 by the China Overseas Group Limited approved consent, launched acetic acid with an annual output of 30,000 tons, 25,000 and 10,000 tons of acetaldehyde crotonaldehyde aldehyde chemical projects.

为加快自身热电资源的综合开发利用，中海黄桥热电有限公司和泰兴市黄能水泥制造有限公司在广泛开展市场调研的基础上，于2005年9月9日经中国海外集团有限公司批准同意，上马年产3万吨醋酸、2.5万乙醛和1万吨巴豆醛的化工项目。

The emphasis was on chemical properties,application,main production methods,market,and prospects of main deriva- tives of acetaldehyde such as ethyl acetate,pentaerythritol,glyoxal,peracetic acid, crotonaldehyde and pyridine.

介绍了国内外乙醛及其主要衍生物的生产技术发展及其市场供需状况，尤其对乙醛主要衍生物乙酸乙酯、季戊四醇、乙二醛、乙醛酸、丁烯醛、吡啶的化学性质与用途、主要生产方法、市场供需状况及开发前景作详细介绍和分析。

Polyvinyl alcohol acetalizing conjugated olefine aldehyde; starch; crolein; crotonaldehyde; reaction mechanism

工程科技I，化学，高分子化学聚乙烯醇缩共轭烯醛；淀粉；丁烯醛；丙烯醛；反应机理

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。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。