查询词典 dehydration

The invention comprises the steps of dehydration reaction, purification treatment, bromization ring contraction integral reaction, separation, refining and by-product processing.

本发明包括脱水反应步骤、纯化处理步骤、溴代缩环一体化反应步骤、分离步骤、精制步骤和副产物加工步骤。

The outpouring of mucus from hypertrophied bronchial submucosal glands, the bronchoconstriction , and dehydration all contribute to the formation of mucus plugs that can block airways in asthmatic patients.

支气管黏膜下层的腺体肥大分泌黏液，支气管壁的破坏和脱水均有助于黏液栓的形成并阻塞哮喘病人的气道。

It was found that the dehydration of ethanol over zeolite catalyst followed carbonium ion reaction mechanism, and thus the formation of ethylene, propylene and propane as the main products was well explained.

乙醇在分子筛催化剂上催化脱水反应过程遵循正碳离子机理，较好地解释了主要产物乙烯、丙烯和丙烷的生成机理。

To the cases with prominent high pressure, dehydration should be applied cautiously to avoid cardial or renal failure.

本病有显著高颅压者过多使用脱水剂宜谨慎，以防出现心、肾功能衰竭。

The dehydration rate and survival rate of Caryopteris clandonensis 'Worcester Gold' were studied under the conditions of 2 kinds of temperature and humidity, 5 treatments to root system, and different preserving time.

研究了温度和湿度、5种根系处理、不同贮藏时间对金叶花失水率、成活率的影响。

By comparing the dehydration methods of three catalytic esterification reactions and the catalysts used under negative pressure, the better method of synthesizing 2 ethylhexyl chloroacetate is using stannous oxide as catalyst under negative pressure.

通过对三种催化酯化反应的脱水方法及负压下使用不同催化剂的比较和选择，提出了以氧化亚锡为催化剂负压脱水合成氯乙酸2乙基己酯的方法。

The main stem, the cotyledonary branch, the dehydration rate and other parameters were observed. The methods of direct evaluation, comprehensive indirect evaluation and the clustering analysis were used to evaluate the drought resistance of M3 generation.

通过田间小区试验对M3代主茎高，侧枝长，叶片失水率等指标进行观测，运用直接评价，间接综合评价以及聚类分析方法对M3代抗旱性能进行分析。

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。

A synthesis of 2-pentylidene cyclopentanone starting from cyclopentanone and n-valeraldehyde through aldol condensation, followed by dehydration, was studied, and the yield reached 85.6%. 2-Pentenyl cyclopentanone was prepared in a yield of 95.0% from 2-pentylidene cyclopentanone with a hydrogenation methodology. Through Baeyer-villiger oxidation,δ-decalactone was synthesized in a yield of 63.9% from 2-pentenyl cyclopentanone with hydrogen peroxide.

研究了以正戊醛和环戊酮为起始原料，经羟醛缩合、脱水反应合成2-戊叉环戊酮，产率达到85.6%，2-戊叉环戊酮加氢制备2-戊基环戊酮，产率为95.0%，2-戊基环戊酮在双氧水作用下经Baeyer-villiger氧化重排反应合成δ-癸内酯，反应产率为63.9%，合成δ-癸内酯的总产率为52.0%，气相色谱分析纯度为98.7%。

In this thesis, the author importantly clarified the process engineering of natural gas which used in the development of Sulige gas field, the process engineering is ammonia refrigeration and low temperature separation, dehydration and dealkylation , and analyzed the operation effect of the processing.

本文重点对苏里格气田开发过程中采用的氨制冷低温分离脱水脱烃天然气处理工艺的应运情况进行了阐述，运行效果进行了分析，为苏里格气田的大规模开发提供技术依据。

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。