查询词典 acetal

Synthesis of organic sulfuric compounds in aqueous media is carried out by: using thio-olefin compounds with carbonyl compounds, acetal/keltone, hydrazone, oxime, osazone and enamine to synthesize mercaptal/keltone compounds in aqueous media; using thio-olefin compounds with alpha-hydroxyaldehyde/keltone or alpha-halogenated aldehyde/keltone to synthesize thia-olefin derivatives in a queous media; using thio-olefin compounds with alpha, beta-unsaturated hydroxy compounds, C-C treble bond, C-N treble bond, C-C double bond, N-N double bond, C-N double bond, C-S double bond, epoxy and its derivatives, aziridine and its derivatives, cyclopropane and its derivatives and halogenated carboxy to synthesize sulfoether compounds in a queous media.

含水介质中有机硫化合物的合成方法，本发明属于有机合成方法，用硫缩烯酮类化合物与羰基化合物、缩醛/酮、腙、肟、脎、烯胺在含水介质中合成缩硫醛/酮化合物，与α-羟基醛/酮或α-卤代醛/酮在含水介质中合成噻烯类衍生物，与α，β-不饱和羰基化合物、碳碳叁键、碳氮叁键、碳碳双键、氮氮双键、碳氮双键、碳硫双键、环氧乙烷及其衍生物、氮杂环丙烷及其衍生物、环丙烷及其衍生物、卤代烃等在含水介质，中合成硫醚化合物。

Bis-imidazoline was prepared from triethylene tetraamine and N,N-dimethylformamide dimethyl acetal at 85℃ for 2 h with toluene as solvent, with a yield of 90.4%. The reaction of bis-imidazoline with 1,2-dibromoethane and potassium carbonate in acetonitrile provided with a monobromide salt yield of 78.7%. Hydrolysis of monobromide salt under aqueous causic solution formed 1,4,7,10-tetraazzcyclododecane in a 74.2% yield.

用甲苯作溶剂，使三乙烯四胺和N，N-二甲基甲酰胺二甲基缩醛在85℃反应2 h，得到中间体双咪唑啉，产率90.4%，在乙腈溶剂中，碳酸钾存在下，双咪唑啉和1，2-二溴乙烷进行扩环反应，得到环状中间体一溴盐，产率78.7%，一溴盐经碱性水解2 h，得到1，4，7，10-四氮杂十二烷，产率74.2%。

In the existing process of PVB, it has disadvantages of unsteady aldehyde groupdistribution, low content of aldehyde acetal group .

本文针对聚乙烯醇缩丁醛传统生产工艺生产的PVB存在缩醛基分布不均，缩醛度低等缺陷，系统地研究了分阶段醇解一缩合的均相工艺，二甲基亚砜的均相工艺以及极性匹配的醇法均相工艺。

The products we produced,shuch as stainless steel filtration element, graphite gasket, DAS combination seal, urethane or acetal resin material sealings, are well welcome and accepted all over the world.

塞普公司优秀和专业的员工队伍，保证了我们所提供的产品质量和服务品质。我们以&创新、优质、认真、服务&为宗旨，热情地欢迎海内外的客商来我司指导和垂询。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。