气相色谱法研究负载型稀土醋酸酉己位化合物的热稳定性

本文以程序升温一气相色谱法研究以MgO,SiO_2及γ-Al_2O_3作载休的负载型稀土醋酸盐及其相应纯盐在氢气中的热分解行为。实验结果表明稀土醋酸盐在H_2中的热分解反应可以分为三个阶段:1.释放出丙酮;2.释放出丙酮,二氧化碳,并形成Ln_2O_3及Ln_2O_3·CO_2;3.生成CO。 在载体作用下,稀土醋酸盐的分解温度降低,其中性载体SiO_2的影响较小,MgO载体使稀土醋酸盐分解温度明显降低。从Y,La到Pr随着稀土离子离子势增加载体的作用反而减小,但从Pr到Nd、Sm、Er随着稀土离子势的增加载体的作用又增强,所有三种载体对醋酸谱的影响均小。     

模拟萃合物二（二甲基甲酰胺）氯化醋酸铀酰ＵＯ２（ＯＡc）Cl（DMF）2的结构测

根据堆积模型可以推测新的萃取体系，最近，我们发现：不仅在两种萃取剂之间，而且在两种简单的萃取介质之间也可以产生协同效应，并且用实验证实了在醋酸盐与氯化物的混合介质中可以协同萃取铀酰。     

[La(CCl3COO)3(bipy)·H2O]2和Tb(CCl3CO)3(bipy)2·H2O混配 配合物的合成及其结构测定

利用不同溶剂合成并测定了希土三氯醋酸盐与α,α'-联吡啶(bipy)不同比例的配合物(Ⅰ)La:bipy=1:1,[La(CCl₃COO)₃(bipy)·H₂O]₂和(Ⅱ)Tb:bipy=1:2,Tb(CCl₃COO)₃(bipy)₂·H₂O,结构测定表明配合物(Ⅰ)与(Ⅱ)均为三斜晶系,中心离子La(或Tb)具有配位数为8的畸变四方反棱柱多面体;但是配合物(Ⅰ)形成具有对称中心的二聚体。     

Novel N,N＇-Diacylhydrazine-Based Colorimetric Receptors for Selective Sensing of Fluoride and Acetate Anions

Three novel and simple N,N＇-diacylhydrazine-based colorimetric receptors have been prepared. The binding properties of the receptors to anions such as F^-, Cl^-, Br^-, AcO^-, HSO4^- and HEPO4^- in acetonitrile solution were examined by UV-Vis spectroscopy methods, which show high sensitivity and selectivity to F^- and AcO^- over other anions. The results indicated that a 1 ： 1 stoichiometry complex was formed between the receptors and the anions, while ^1H NMR titrations confirmed hydrogen binding interaction between the receptors and the anions.     

Solid Superacid Catalyzed Efficient Synthesis of 2-Diethylaminoethyl Aryloxyacetates

2-Diethylaminoethyl aryloxyacetates are prepared efficiently in 75～95% yields by condensation of the corresponding aryloxY2acetic acids with 2-diethylaminoethanol in the presence of catalytic amount of solid superacid SO4 ^2-/Fe2O3.     

Researches on Formation of Haloacetic Acids in Chlorination of Drinking Water by a Novel Technique

Haloacetic acids (HAAs) are formed during the chlorination of drinking water, which are harmful to peo-ple′s health due to their carcinogenic and mutagenic effects. In the present study, a detection method combin-ing methyl tert-butyl ether (MtBE) extraction with acid catalysis and gas chromatography coupled with anelectron capture detector (GC/ECD) was developed for determining HAAs. The detection limit of this method(MDL) and relative standard deviation (RSD) were below 0. 37μg/L and 6.2%, respectively. The laboratorychlorination experiments were conducted with the purpose of investigating the influences of reaction time,temperature, UV254, bromide and ammonia-nitrogen on the formation of HAAs. The results show that theformation amount of HAAs increases with increasing reaction time and temperature, respectively;and thereexists a linear relationship between the formation of HAAs and UV254. The formation amount of HAAs de-creases first and then increases as the bromide ion concentration increases, and adding NH4^ is a possible wayto control the formation of HAAs.     

金属醋酸盐催化合成聚丁二酸乙二醇酯预聚体和碳酸二甲酯

研究了醋酸盐催化碳酸乙烯酯（EC）和丁二酸二甲酯（DS）同时合成聚丁二酸乙二醇酯 (PES) 预聚体和碳酸二甲酯(DMC)的耦合反应新工艺。 采用气相色谱-质谱联用定性分析馏分组成;红外光谱、核磁共振表征了预聚物的结构;采用乌式粘度计测试了预聚物的特性粘数;气相色谱定量测定馏分碳酸二甲酯的收率以考察耦合反应的进度。 以对该反应催化效果最佳的无水醋酸锂为催化剂考察了物料配比、反应温度、反应时间、催化剂用量对耦合反应的影响,结果表明,最佳的工艺条件为：反应温度195～200 ℃,n(EC)∶n(DS)=2∶1,n(cat)∶n(EC+DS)=0.02∶1,反应时间为2 h,耦合反应所得的DMC收率为48.0%,聚丁二酸乙二醇酯预聚物的特性粘数为0.3787。     

离子液体1-丙基-3-甲基咪唑醋酸盐[C_3mim][OAc]蒸气压和蒸发焓的测定及极性预测

<正>~~