预测三元系超额焓的一种新方法

提出一种预测三元系超额焓的新方法。该方法利用改进的立方状态方程－－ＦＲＫＳ方程，并以二元互作用参数函数代替单一数值的二地互作用参数，为计算体系提供随状态变化的二元互作用参数数值。对十二个非理想三元系及其组分二元素的计算结果表明，该方法明显提高了二元系超额焓的拟合精度，从而在不引入任何三元参数的条件下较好地改进了三元系超额焓的预测。     

用FRKS状态方程预测三元系超额体积

利用改进的立方状态方程－ＦＲＫＳ方程，并以二元互作用函数代替单一数值的二元互作用参数关联二元系的超额体积，得到二元参数，在不引入任何三元参数的情况下，直接用组分二元系作用函数的引入预测三元系的超额体积，对十二个三元系及其组分二元系的计算结果表明，二元互作用函数的引入明显提高了二元超额体积的拟合精度，从而使状态方程法能精确地预测三元系的超额体积。     

用二元交互作用函数预测高压下多组分体系的气液平衡

用和体系的状态有关且满足不变性条件的二元交互作用函数,结合F函数修改的立方状态--方程FRKS方程,预测高压下多组分体系的气液平衡.选择15个三元体系及其组分二元系来检验方法的可行性,这些体系覆盖了从简单的接近理想溶液行为的体系到高度非理想体系.计算结果表明,该方法不仅能相当精确地关联各种类型二元系的气液平衡,而且能在仅用组分二元系参数的条件下较准确地预测所考察的所有三元体系的气液平衡     

乙酸乙酯-水二元物系汽液平衡的研究

本文使用自行设计的带机械搅拌器的平衡釜,在760mmHg压力下,测定了乙酸乙酯-水二元部份互溶物系的汽、液平衡数据.经热力学检验,该数据符合热力学一致性.用NRTL等13个活度系数方程进行热力学关联和计算,获得了满意的结果,尤以McCann方程和NRTL方程拟合的精度最佳.     

定量AES分析中基体效应的迭代修正法

以Shimizu提出的定量AES分析关系为基础,作者提出一种可用于二元和多元合金定量AES分析的迭代方法。通过引入合金的原子序数和原子密度的概念,计算了合金中元素的基体效应修正因子。与其它方法不同的是,本法中基体效应修正因子是合金元素浓度的函数,受到整体组分的影响。通过对文献报道的五种典型单相多晶二元合金Ag-Pd,Ni-Pd,Cr-Fe,Mo-Fe和Ni-Mg的定量分析计算发现,本法的分析精密度优于F因子法、K因子法及改进K因子修正法。     

近临界下HZSM-5催化的甲苯歧化反应

用高压观测池通过可视观测确定了苯、甲苯和对二甲苯等二元系及三元系的临界性质以及甲苯歧化反应混合物临界性质随着反应进程的变化规律；在此基础上，分别研究了近临界区以及高温下以HZSM-5为催化剂的甲苯歧化反应。结果发现，在近临界区甲苯歧化反应的对二甲苯选择性最高，随温度的升高甲苯转化率明显增加，对二甲苯选择性下降。高温下压力对对二甲苯选择性没有影响，转化率随压力升高而提高。     

三元——假二元系的过量体积

提出测量三元——假二元系(1-x)[(1-y)A+yC]+z[(1-y)B+yC]的过量热力学函数的方法, 测量了在298.15 K下两种假二元系: A=环己烷, B=苯, C=甲苯, 甲基环己烷的过量体积V~E, 用van der Waals单流体模型对实验结果进行了讨论。     

对甲氧基苯甲醛与N,N-二甲基甲酰胺密度黏度的测定与关联

在常压,298.15K~353.15K条件下,采用U形振动管密度计测定了对甲氧基苯甲醛-N,N-二甲基甲酰胺二元物系的密度,采用乌氏黏度计测定其黏度;并由密度和黏度数据分别计算了该二元物系超额摩尔体积VE和混合黏度的变化Δη.在不同的温度和组成下超额摩尔体积和混合黏度的变化都是负值,同时对不同温度下的超额摩尔体积与组成的关系以及混合黏度的变化与组成的关系都按Redlich-Kister方程进行了拟合,计算值与实验值的最大标准偏差小于7%.     

计算金属间化合物热力学性质的新方法

用一简单的相关函数式对金属间化合物的热力学性质进行拟合，提出了一种计算金属间化合物热力学性质的新方法，并用此方法计算了二元金属间化合物的常温热容和熵。计算结果表明，该方法简单，且能满足一定的计算精度，有一定的实用价值。     

利用液相色谱–质谱联用技术研究二元表面活性剂体系–啶虫脒微乳剂热贮稳定性

应用液相色谱–质谱联用技术评价复配的阴/非离子二元表面活性剂复合体系–啶虫脒微乳剂的热贮稳定性。将二元表面活性剂复合体系–啶虫脒微乳剂于(54±2)℃下贮藏14天,取出后于室温下干燥24 h,用液相色谱–质谱联用仪测定啶虫脒含量。该法线性拟合方程为y=97 060.72x+542 587.4,线性范围为0.01~0.25 mg/L,相关系数为0.999 8。方法检出限为0.001 mg/L(S/N=3),色谱保留时间和色谱峰面积重复性分别为0.31%,1.44%(n=6),加标回收率为86.23%~107.20%。该法具有简单、准确和灵敏的特点。     

Surface tension and density of binary mixtures of monoalcohols,water and acetonitrile: equation of correlation of the surface tension

Measurements of the surface tension (σ) and density (ρ) of binary mixtures of monoalcohols, water and acetonitrile at 298.15 K and at atmospheric pressure, as a function of mole fraction (x) have been made. The experimental values of the deviation of surface tension and the excess of molar volume (Δσ, V ^E) have been correlated by the Redlich–Kister equation. An empirical correlation equation is presented for the study of the surface tension of these mixtures, and comparisons are made of the experimental values of surface tension versus those obtained with the correlation equation and with other models of correlation. Finally, with the purpose of corroborating the validity of the correlation equation, the latter is applied to other reference binary mixtures.     

Viscosity Arrhenius parameters correlation: extension from pure to binary fluid mixtures

Knowledge of fluids’ physicochemical properties is mandatory for the design and optimisation of industrial processes and products. A data quantity of most importance, in this regard, turns out to be the value of fluid viscosity. Many empirical and semi-empirical formulas have been proposed in the literature to describe the viscosity of pure liquids and binary liquid mixtures. Recently, an interesting equation is proposed for pure solvents correlating the two parameters in the viscosity Arrhenius-type equation, namely the activation energy (E_a) and the pre-exponential factor (A_s). This paper aims to extend the said correlation to binary liquid mixtures. To achieve this purpose, statistical methods are applied using data sets from the literature of some solvent binary mixtures at different compositions and temperatures. The validation of the extended proposed equation for binary liquid mixtures is important since it simplifies the estimation of viscous behaviour and the ensuing calculations.     

Hydrodynamic Correlation Functions for Binary Mixtures

Abstract

Correlation functions of various local thermodynamic variables of binary mixtures are obtained from the linearized hydrodynamic equations following the method of Mountain and Deutch. “Non-Lorentzian” parts of the time Fourier transformed correlation functions which have not been included by these authors are obtained here and their effect on the light scattering spectrum considered. An extension of the treatment by Fox and Uhlenbeck of Landau and Lifshitz hydrodynamical fluctuation theory to binary mixtures has been accomplished and correlation functions of the "fluctuating forces" are obtained for this case.     

二元复杂共混体系组成的SEC-LS分析

提供了一种利用体积排阻色谱-光散射(SEC-LS)联用技术来解决二元复杂共混体系组成的定量分析问题.基于体积排除色谱的绝对定量化原则,首先从理论上分析了共混物的光散射响应因子与组成呈线性关系.通过分析六组复杂共混体系的光散射响应因子与组成的关系,验证了该线性关系确实存在.进而利用该线性关系计算了共混体系的组成.在某些共混体系中,通过光散射响应因子得出的组成比利用示差法得出的组成更加接近原料组成.通过分析这两种方法产生误差的来源,阐述了产生该现象的原因.     

Temperature Dependence of Kerr Coefficient of Binary Liquid Mixtures of Aprotic-Aprotic Molecules

Abstract

The electro optical Kerr coefficients of binary liquid mixtures, comprising of aprotic-aprotic molecules only, are measured over the temperature range of 286 K to 315 K. To with in experimental errors, the logarithm of Kerr coefficient can be expressed as Van't Hoff type expression to the reciprocal of temperature. Information on the interaction energy between the constituents of the binary mixtures is thereby obtained. It is found that the interaction energy in aromatic ketone-aliphatic nitrile binary mixtures is comparatively higher than in the binary mixtures with aliphatic ketone-aliphatic nitriles, aromatic ketone-aromatic nitrile and aromatic ketone-aliphatic ketones components. This is attributed to the dipole-dipole interaction existing between the components of the binary mixtures.     

聚合物二元共混物拉伸强度混合规则的改进模型

改进了关于聚合物二元共混物拉伸强度混合规则的模型 ,保留了原模型中分别表征共混物界面和相结构对共混物拉伸强度产生影响的两个因子F和M .用此模型处理了三个共混体系的拉伸强度数据 ,反算出共混体系的界面强度因子F和相结构强度因子M ,结果表明 ,该改进模型的预测值与实验结果相符程度与原式几无差别 ,但使F和M的物理意义更为明确、合理 ,其相关系数也有所增大     

Determination of the Concentrations of Binary Mixtures of Glycerine and Water by a Transient Method

The conductivities of binary mixtures of glycerine and water were measured at 20°C by means of a transient method. The equation describing the correlation between concentration and thermal conductivity was determined. The equation can be used for determining concentrations in mixtures. The results show that (1) the error in the determination of the molar concentration of water in mixtures is less than 1%, (2) the time of measurement is 1 s, (3) this method can be used for on-line analysis in production control. This revised version was published online in July 2006 with corrections to the Cover Date.     

Thermochemical investigations of nearly idial binary solvents. 6. Solubilities of iodine and benzil in systems of nonspecific interactions

Solubilities have been determined at 25°C for iodine in binary mixtures of carbon tetrachloride with cyclohexane, n-hexane, n-heptane, and octamethylcyclotetrasiloxane (OMCTS) and in mixtures of cyclohexane with n-hexane and OMCTS; and for benzil in binary mixtures of carbon tetrachloride with cyclohexane, n-hexane, and n-heptane, mixtures of n-hexane with cyclohexane and n-heptane, and mixtures of benzene with cyclohexane and toluene. With the exception of the benzene+cyclohexane system, the nearly ideal binary solvent model predicts these solubilities with a maximum deviation of 6% and an overall standard deviation of 2.4%. The model correctly predicts minima for solubility (mole fraction) of iodine in the OMCTS systems, and predicts solubilities within 4% for benzil in the carbon tetrachloride+n-hexane system, in which the solubility changes by a factor of 14. The failure of the model for predicting solubilities of benzil in mixtures of benzene and cyclohexane (maximum error of 25% for and 18-fold range of solubilities) is possibly due to specific interactions between benzil and benzene.     

Thermal Analysis of Solid-Solid Interactions in Binary Mixtures of Alkylcyclohexanes Using DSC

Differential scanning calorimetry (DSC) was used to construct phase diagrams of binary mixtures of alkylcyclohexanes and to characterize metastable phases formed in the binary mixtures. The experimentally measured liquidus curves were compared to the liquidus curves calculated using ideal solution theory. The measured phase diagrams of pentadecylcyclohexane/nonadecylcyclohexane and octadecylcyclohexane/nonadecylcyclohexane binary mixtures are consistent with theoretical phase diagrams constructed based on the assumption that these mixtures form eutectic systems. It was also observed that a metastable phase formed in some binary mixtures of pentadecylcyclohexane/nonadecylcyclohexane under fast cooling conditions. It is hypothesized that this metastable phase recrystallizes into the eutectic phase upon heating. This revised version was published online in July 2006 with corrections to the Cover Date.