甲醛

The synthesis of acrolein by means of the catalytic vapor phase condensation of formaldehyde and acetaldehyde was studied.

利用冷凝甲醛和乙醛的气相催化法，来研究丙烯醛的合成。

The human exposure levels of formaldehyde and acetaldehyde in hospitals were discussed.

对医院甲醛、乙醛在人体内的暴露水平做了讨论，与其他类似场所相比，医院的暴露风险相对较小。

Formaldehyde, acetaldehyde and acrolein are common aldehyde in the environment.

甲醛、乙醛和丙烯醛均为环境中常见的醛类。

Some by-products are benzene, acetone, xylene, formaldehyde, and acetaldehyde.

一些副产品都是苯、丙酮、二甲苯、甲醛和乙醛。

Main Products polyformaldehyde, ethylene dichloride, dichloroethane, acetic anhydride, etc. in the industry has a good reputation.

主营产品多聚甲醛、二氯乙烯、二氯乙烷、醋酸酐等在业界具有较好的声誉。

Copper was reduced by formaldehyde which was contained in the effluent of chemical copper plating , and EDTA in the effluent was reclaimed after acidify.

探讨了利用原化学镀铜废液中的甲醛将铜还原，后酸化回收 EDTA的新工艺。

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。

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 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。

Urea-formaldehyde resin adhesives are widely used in the production of plywood because of their good adhesiveness and low cost, but the problem of formaldehyde released from UF has attracted more and more attention. Therefore, the study and use of environmental friendly resin adhesives containing no formaldehyde become to be the focus of the researches.

脲醛树脂由于其良好的粘接性能及较低的生产成本被广泛应用于胶合板的生产中，但其甲醛释放问题却引起越来越多的关注，因此开发使用无醛的绿色环保型胶粘剂就成为目前胶粘剂研究工作的核心。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。