; The processes of neucleation and growth of latex particles in emulsion polymerization for the more hydrophilic monomers such as VAc are studied. A mathematical model is proposed for stage I of emulsion polymerization of VAc. The model considers the neucleation mechanisms both by micelles and by oligomer precipitation. Meanwhile, the effects of free radical desorption from latex particles to aqueous phase and the amount of emulsifier adsorbed onto monomer droplets on the kinetics of stage I of the emulsion polymerization for VAc are taken into account. Furthermore, the prediction results by the model and the experimental data are compared and discussed.

The kinetics of emulsion polymerization for the more hydrophilic monomer VAc is studied. The effect of free radical desorption and the contribution of the polymerization in aqueous phase to total polymerization rate are analyzed. A mathematical model for stage II and I of emulsion polymerization of VAc is proposed. It can be successfully used to predict the polymerization rate, the distribution of free radicals among latex particles and the change of the average number of free radicals in one particle along with monomer conversion. The model prediction and experimental data are compared and discussed.

A new molecular thermodynamic model for water is developed in which water molecules are taken as "softened" hard spheres with dispersion, induction and electrostatic interactions. The expressions for thermodynamic functions such as Helmholtz free energy, equation of state and vaporization enthalpy are derived according to perturbation theory. The molecular parameters are obtained by fitting experimental vapor pressure and liquid density data simultaneously in a temperature range of 0-300℃ . Meanwhile the vaporization enthalpy and specific volume of vapor are predicted with a small deviation. Moreover, some molecular thermodynamic models for water are compared. The results show that our model is simple and accurate.

On the basis of a thermodynamic model of liquid mixtures, the expression of excess Gibbs free energy derived for non - electrolyte solutions is more strict than those of Scatchard - Hildebrand theory of regular solutions. A new solubility parameter thereby defined equals to the cohesive energy density of the liquid divided by the square root of internal pressure. The prediction results of excess Gibbs free energy show that its deviation from the experimental values is less than those of SH theory and the modified SHFH theory for most of thirty - five binary liquid mixtures, especially in solutions of fluorocarbons and hydrocarbons where SH and SHFH theory are not applicable.

A dynamic model of plate - fin heat exchangers was studied. The dynamic mathematical model of heat exchangers was established by using the lumped parameter method, especially the theory of the equilibrium surface "continuous method" of analysing the static and dynamic characteristics of heat exchangers was introduced. The accuracy of the lumped parameter method was verified by comparing the results of the lumped parameter method and the numerical method and the test. The characteristics of the equilibrium surface "continuous method" of analysing heat exchangers were thus demonstrated.

Steam nozzles were used to pump liquid in a climbing - film evaporation experimental system. In fact, a jet was formed by the nozzle and an evaporation tube. Two phase flow and heat transfer of climbing- film evaporation with steam injection pumping were studied experimentally and theoretically. The experimental results showed that steam injection enhanced heat transfer of evaporation and only a small amount of steam was consumed for pumping. A heat transfer model was presented, in which effects of interfacial wave on heat transfer were considered. The model was found in good agreement with the experimental data.

An analytical method based on Dirac activity distribution has been developed to reduce the catalyst pellet model from a set of differential equations to algebraic equations. This method can be used to analyze the complex nonlinear performance of a catalyst pellet with arbitrary kinetics.

On the basis of the previously developed Dirac analysis method and theory, the reduced transfer - reaction model of a catalyst pellet is solved by computer. The general strategy of analyzing the transfer and reaction interaction in a catalyst pellet by the Dirac analysis method is further discussed.

The absorption of CO2 by an aqueous mixture of N-methyldiethanolamine (MDEA)and monoethanolamine (MEA)has been investigated. A simplified and approximate mass transfer rate model based on film theory is developed and used to predict the ratc of absorption of CO2 by an aqueous solution of mixed amines. This model accounts for interaction between chemical reactions and assumes cubic concentration profiles for reactants in the film. The rates of absorption of CO2 by an aqueous MDEA/MEA system are determined in a stirred cell reactor under a wide range of conditions. The results obtained from the model are in good agreement with experimental values.

A mathematical dynamic model for the fractionator of the Fluidized Catalytic Cracking Unit (FCCU) has been developed. In this model the liquid products of the catalytic cracking are described by four pseudocomponents. Material balance and enthalpy balance are written for each plate. The supplementary equations of this model include plate hydraulics and vapor- liquid equilibrium of pseudocomponents were selected from existing correlations and linearized enthalpy models of pseudocomponents and inert components were put forward by the authors. The results of the simulation experiments show that this dynamic model can predict the dynamic and static responses of each plate when the operating conditions of the fractionator are changed. The predictions of this model fit in with the data of an industrial FCCU fractionator.

The three dimensional non-equilibrium mixing pool model is simplified. The sensitivity analysis of the model parameters reveals that liquid flow pattern on a tray is the most important factor affecting the result, while liquid flow distribution between pools and eddy diffusivity are shown to be insensitive parameters.

The extensional stresses and elongational viscosities of sesbania aqueous solution were measured by a self- made extensional rheometer. The extensional stresses and elongational viscosities gradually increased with strain rate, which explained the significant increase in flow resistance observed in a porous medium. The results also showed that the modified Williams- Bird constitutive equation with four parameters is suitable for either shear flow or elongational flow of sesbania aqueous solution.

Ultrafine Al2O3- SnO2 composite particles were prepared by fluidization chemical vapor deposition technology with SnCl4-H2O-N2 systems. By the methods of TEM, XRF, HREM ,the distribution of SnO2 over Al2O3 particle surface and the effect of operating parameters on forming films and producing particles were studied. The mechanism of chemical vapor coating was expounded

A semi- empirical correlating and predicting system for activity coefficients is proposed. The activity coefficients of binary systems are predicted by an excess Gibbs energy model in which the model parameters are evaluated from two algebraic equations which relate limiting activity coefficient and (dr/dx)x=0 to the model parameters. The Limiting activity coefficient is correlated with the MOSCED model, and (dr/dx)x=0 from Hansens three -dimensional solubility parameters. Predictions for 145 isothermal polar binary systems are compared with experimental values.

A stability analysis was made on the interface of the stratified gas- liquid two-phase flow in a inclined circular pipe by using a two- fluid model, and the dispersive equation of the interfacial waves was deduced. The effects of gas and liquid flow rates, tube diameter, liquid viscosity and tube inclination on interface stability were investigated.

An experimental study was conducted to determine flow patterns and their transitions on the shell -side of a TEMA -F model heat exchanger using an air -oil mixture. Flow patterns were obtained. Dimensionless correlations for determining flow regime transitions and new correlations for predicting void fraction and two - phasee pressure drop in the window zone were presented.

A simple holographic interferometric system is designed. The interferograms of thermal diffusion in air are processed and measured by means of a computer image analyzing and processing system. The temperature distributions of two sections in the air flow are reconstructed and compared with thermal couple measurements at three points.

Iron black cathode is a new electrode material for cathode in the industry of chlorate electrolysis. Its structure and composition are examined by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The overpotentials of hydrogen evolution on the iron black cathode in the electrolyte of chlorate electrolysis decrease by 260-270mV(65±2℃) in comparison with the original iron cathode. During 90 days of life test hydrogen overpotentials of iron black cathode are lower than that of original iron cathode by over 240 mV under the conditions of current density 2kA/m2 and temperature 65±3℃.

A transient method of measuring heat transfer coefficients inside a tube has been presented. The heat transfer coefficients between fluid and wall surface is determined by means of the propagation characteristics of periodically oscillating temperature changes. To reach this purpose, the phase shift or the amplitude ratio between fluid and wall temperatures is experimentally measured. The test apparatus has been designed and set up to carry out experiments. The discussions about the measuring method and experimental results are given in detail.

The ultrasonic wave properties of a mixed solution of trioxane and dichloroethane have been studied. A high- precision ultrasonic wave instrument controlled by a personal computer is used to precisely measure the ultrasonic flight- time under the conditions of concentrations 0-48% and temperatures 0-40℃. This paper also calculates the relationships between ultrasonic flight- time, temperature and concentration of trioxane in dichloroethane, which provide the basis for on- line concentration measurement of a mixed solution of trioxane and dichloroethane by ultrasonic method.

Three groups of ternary VLE data for methanol- ethanol- water, 1-propanol-ethanolwater and iso- butyl alcohol- ethanol- water containing a small amount of impurity in a fermentation alcohol system were determined under absolute pressure of 53. 32 kPa with an improved Rose equilibrium still apparatus. The data were correlated by the Wilson, NRTL, UNIQUAC activity coefficient model, and their energy parameters were determined for each system. The results were in good agreement with the experimental data.