三元链状分子系统液液平衡的Monte Carlo模拟和分子热力学模型

在格子模型基础上,采用构型偏倚蒸发法（CBVM）对三元链状分子系统的液液平衡进行了Monte Carlo模拟,分别考查了分子链长和链节间相互作用参数对相区的影响。模拟发现,在保持交换能参数一定的情况下,互溶区随高分子之一的链长的增加而减小。在各组分链长不变的情况下,分相区随交换能的减小而增加。修正的Freed模型（RFT）可较满意地再现模拟结果,而Ftory—Huggins模型总是过低地估计互溶区。RFT模型可满意地关联和预测苯-庚烷-二甘醇系统的二元和三元液-液平衡数据。     

反相气相色谱法测定溶液在高分子中的无限稀释活度系数

1 INTRODUCTI0NDue to its short experimental time,little sampleneeded,suitable for broad temperature range,inversegas chromatography(IGC)has been widely used tomeasure variety of properties of polymer systems,suchas the infinite diluted activity coefficients of solvent inpolymer,the glass transition temperature of polymerand the surface properties of polymer,etc.Those     

借鉴化学原理,引导学生回归课堂

当前国内外大学校园普遍存在如何使背离课堂的学生回归这一难题。我们对此进行了探究,分析了学生背离课堂的原因,并结合实际工作经验初步探讨了如何借鉴化学原理,引导学生回归课堂。本文对于国内外教育教学实践者及管理者均有借鉴意义。     

乙醇在聚氨酯/乙烯基酯树脂互穿网络中的吸收动力学及传递分析

采用石英弹簧称重法测定了乙醇在几种聚氨酯（PU）／乙烯基酯树脂互穿网络（IPN）中的吸收动力学数据，用蠕变传递模型对实验数据进行关联，并对IPN的微观结构进行了分析。结果表明：乙醇在PU／含促羟基的乙烯基酯树脂（CBIPN）膜和PU／正丁醇接枝乙烯基酯树脂（HBIPN）膜中的D远大于在PU膜和PU／不含仲羟基的乙烯基酯树脂（PIPN）膜中的D，关联得到的CBIPN和HBIPN膜的杨氏模糊也远大于纯PU和PIPN膜，与其它实验结果相吻合，说明在网络间引入化学键或氢键作用能有效地改善聚氨酯／乙烯基酯树脂互穿网络的相容性，从而提高材料的力学性能     

乙烯-苯-乙苯三元系临界温度和临界压力研究

Critical temperature (Tc) and critical pressure (pc) of the ternary mixture of ethylene benzene ethylbenzene (the mole ratio of ethylbenzene to benzene was fixed at 0.95:0.05) were measured by using a high=pressure view cell with direct visual observation.The interaction coefficients obtained from the critical properties of the relevant binary systems were used to predict the critical properties (Tc,pc) of the ternary mixture.The agreement between the prediction and experiments is satisfactory.     

共聚高分子溶液的分子热力学模型

引　言共聚高分子因具有很多均聚高分子所没有的性质而受到人们的广泛关注 .但文献中发表的有关共聚高分子系统的汽液相平衡 (ＶＬＥ)数据较少 ,能够用于关联或预测的分子热力学模型也不多 .最常用的模型是基于密堆积格子模型的Ｆｌｏｒｙ -Ｈｕｇｇｉｎｓ理论及其改进模型 .近年来 ,在严格的统计力学理论基础上建立非格子的链状流体状态方程引起了人们更大的兴趣 ,并相继建立了一些具有实用价值的状态方程[1～ 5] .对于共聚高分子系统 ,Ｈｉｎｏ等人[6 ]建立了实用的状态方程 ,Ｂａｎａｓｚａｋ等人[7] 在热力学微扰理论 (ＴＰＴ1)的基础上…     

离子液体[C4mim][PF6]与N, N-二甲基甲酰胺二元混合物在298.15 K～318.15 K的密度和粘度

Viscosities and densities for 1-butyl-3-methylimidazolium hexafluorophosphate （[C4mim][PF6]） and N, N-dimethylformamide （DMF） binary mixtures have been measured at the temperature range from 293.15 K to 318.15 K. It is shown that the viscosities and densities decrease monotonously with temperature and the content of DMF. Various correlation methods including Arrhenius-like equation, Sedclon et al.＇s equation, Redlich-Kister equation with four parameters, and other empirical equations were applied to evaluate these experimental data. A model based on an equation of state Ior estimating the viscosity of mixtures containing ionic liquids were proposed by coupling with the excess Gibbs free energy model of viscosity, which can synchronously calculate the viscosity and the molar volume. The results show that the model gives a deviation of 8.29% for the viscosity, and a deviation of 1.05% for the molar volume when only one temperature-independent adjustable parameter is adopted. The correlation accuracy is further improved when two parameters or one temperature-dependent parameter is used.     

硬球链流体在狭缝中密度分布的Monte Carlo模拟

Covering a wide range of bulk densities, density profiles for hard-sphere chain fluids (HSCFs) with chain length of 3,4,8,20,32 and 64 confined between two surfaces were obtained by Monte Carlo simulations using extended continuum configurationai-bias (ECCB) method. It is shown that the enrichment of beads near surfaces is happened at high densities due to the bulk packing effect, on the contrary, the depletion is revealed at low densities owing to the configurationai entropic contribution. Comparisons with those calculated by density functional theory presented by Cai et al. indicate that the agreement between simulations and predictions is good. Compressibility factors of bulk HSCFs calculated using volume fractions at surfaces were also used to test the reliability of various eauations of state of HSCFs by different authors.     

异戊二烯在聚苯乙烯高分子膜中的扩散系数测定

为了探讨在反应挤出过程中异戊二烯在聚苯乙烯中的扩散传递机理,采用石英弹簧法测定了298.15K、308.15K和318.15K下异戊二烯在聚苯乙烯膜中的吸收动力学曲线。探讨了温度、压力、分子量对扩散吸收的影响,并对实验结果进行了关联。结果表明异戊二烯在聚苯乙烯膜中的扩散吸收呈S型吸收,由吸收曲线获得了平均扩散系数和平衡溶解度。     

氯化法制备钛白氧化反应器内射流混合特性研究

氧化反应器是制备氯化法钛白粉的核心设备 ,反应器内的混合特征决定了产品性能。文中采用示踪法研究了四氯化钛氧化反应器内径向射流混合特征 ,探讨了射流环开孔结构和动量比等因素对射流混合效果的影响。结果表明 ,射流环开孔结构对混合效果有重要影响 ,复合开孔结构的混合效果比均匀开孔结构的好 ;增大动量比有利于提高射流混合效率 ,对于开孔尺寸小的射流环此影响尤为明显。