查询词典 acraldehyde

Based on the theoretical framework of the leakage and spread of such poisonous and harmful substances as glycol and acraldehyde, this paper advances the graphic simulation of GIS of poisonous and harmful substances.

以石化企业乙二醇、丙烯腈装置产生的有毒、有害物质泄漏、扩散和污染范围的理论模型为根据，提出有毒、有害物质的地理信系统扩散图形模拟方法。

The production methods of glutaraldehyde,including those of addition reaction of acraldehyde , oxidation of 1,5-pentadiol,reduction of glutaryl chloride and oxidation of cyclopentene,are summarized.

综述了丙烯醛加成、 1，5 -戊二醇氧化、戊二酰氯还原和环戊烯氧化等戊二醛的合成路线和制备方法，考察了目前戊二醛的生产厂家及其在皮革鞣剂、油田注水杀菌剂和医药杀菌等领域的应用市

B3LYP/6-311++G** calculations were carried out to study the trimethylamine catalyzed Baylis-Hillman reaction between acraldehyde and formaldehyde.

采用密度泛函DFT-B3LYP方法在6-311++G**基组下计算研究了三甲胺催化的丙烯醛和甲醛的Baylis-Hillman反应的微观过程，获得了两种反应通道(分别对应于顺式-丙烯醛和反式-丙烯醛)的势能面。

So we researched the relationship between the acraldehyde contamination and cooking activity. We choose four time, 9:00 and 15:00 the cooking activity is very few, so the contamination is low, but 11:30 and 17:30 the contamination is very high, this concentration is 2.6 times an much as the front one.

检测结果表明丙烯醛的浓度和烹饪活动的多少有密切的关系。9：00和15：00食堂内烹饪活动比较少，丙烯醛的浓度明显降低，而11：30和17：30是两个就餐高峰，在这两个时间段内餐厅内的丙烯醛浓度明显升高。

The main contamination in dining-room is acraldehyde.

学生食堂内主要污染物是丙烯醛，因此在学生食堂内对丙烯醛的浓度进行了检测。

In the first part, chemical synthesis, including by acraldehyde, malonic ester, ami no lactone and others were discussed and synthesis by hydantoin was emphasized.

第一部分讨论了DL-蛋氨酸及其衍生物的化学合成，包括丙烯醛法、丙二酸酯法，氨基内酯法等，并着重介绍了海因法。

The optimized structures and energies of the reactants, intermediates, transition states and products of two reaction channels (corresponding to syn-acraldehyde and anti-acraldehyde) in gas or in methanol solvent were obtained. The potential energy profiles reveal the processes of the trimethylamine-catalyzed Baylis-Hillman reaction between acraldehyde and formaldehyde in gas or in methanol solvent at the microscope level.

通过研究，获得了三种情况下两种反应通道(分别对应于顺式-和反式-丙烯醛)中涉及的反应物、产物、中间体、过渡态的优化结构及其能量，并由此得到了反应的势能面图，在电子微观层次上揭示了三甲胺催化的丙烯醛和甲醛的Baylis-Hillman反应的微观过程。

The method has been used to determine Phthalic esters in drinking water and seawater sample. 3. Single drop microextraction, followed by gas chromatography with flame ionization detection has been applied to determine Formaldehyde, Acetaldehyde and Acraldehyde in water based on 2,4-Dinitrophenylhydrazine derivatization. Extraction solvent, extraction time and stirrer speed were optimized. Optimal experimental conditions were as follows: 1.6μL toluene microdrop exposed for 30 min in a 3ml aqueous sample placed in 4ml vial and stirred at 600 rpm/min.

以2，4-二硝基苯肼衍生，单滴液相微萃取与气相色谱火焰光度检测器联用测定水样中的甲醛、乙醛、丙烯醛，考察了萃取溶剂、液滴大小、萃取时间、搅拌速度、盐效应等对该方法的影响，并对影响液相微萃取的各种因素进行了系统的阐述，确定了该体系的最佳实验条件，实现了甲醛、乙醛、丙烯醛的提取和富集。

Methacrylic acid-acraldehyde/ montmorillonite nanocomposites were prepared using Na+- montmorillonite via in-situ polymerization of methacrylic acid and acraldehyde in aqueous medium.

采用水溶性聚合单体甲基丙烯酸和丙烯醛在钠基蒙脱土层间直接原位插层聚合制备水溶性MAA-AL/MMT纳米复合材料，通过XRD和TEM对纳米复合材料的结构进行表征，采用TGA、DSC研究了纳米复合材料的热性能，同时考察了甲基丙烯酸与丙烯醛配比及体系pH值对纳米复合材料结构及应用性能的影响。

The reaction process in methanol solvent can be deduced from the computational results with CPCM solvent model and the supermolecular handling, namely the reaction involves four steps in the methanol solvent. The nucleophilic addition of trimethylamine to acraldehyde generates an enolate. Nucleophilic attack of the enolate on the aldehyde forms the carbon-carbon bond, followed by the proton-transfer process and the further elimination generating the product and liberating the trimethylamine catalyst.

对于CH3OH对反应体系的影响，可以综合考虑CPCM溶剂模型及超分子模型下的研究结果，即CH3OH溶剂中反应按四步进行，催化剂三甲胺首先与丙烯醛发生亲核加成，生成的两性离子中间体与甲醛发生类似于Aldol的醛醇缩合，形成碳-碳键，之后发生分子内质子转移，最后经E1cb消除得到产物，并释放催化剂三甲胺。

We are interested in your suggestions about appointing us to be the single dealer.

对贵方建议由我方担任独家经销商一事，我们颇感兴趣。

Three types of empty-shell marriages have been identified. In a devitalized relationship husband and wife lack excitement or any real interest in their spouse or their marriage.

一种是死气沉沉的婚姻：在这种婚姻关系中夫妻俩对于配偶或婚姻缺乏激情，或者缺乏真正的兴趣。