Based on the method of molecular therm odynamics, them asstransfer mechanism at gas-liquid interface is studied theoretically, and a new mathematical model is proposed. Using laser holographic interference technique, the hydrodynam ics and mass transfer characteristics of CO2 absorption are meas ured. It is shown that the calculated results are in good agrement with the experimental data.

Absorption of gaseous species into stationary droplets is a fundamental interest of mass transfer between liquid droplets and ambient gas, which plays a key role in atmospheric environment control and many indus trial applications. In this paper, two different considerations including equilibrium and non-eq uilibrium relations at the interface are used to analyze and predict the absorption time for a physical absorption at a relatively low so lubility of gas. For the equilibrium pattern, in the beginning period of absorption, the mass transfer rate is considerably rapid and afterward becomes slower and slower and finally comes to almost zero as the droplet concentration closes to the saturated value. Diferently, when the non-eq uilibrium model is adopted, the interfac ial concentration increases grad ually with the bulk concentration of liquid droplet, and the absorption rate mildly decelerates with the increase of bulk one throughout the process, which lead s to a longer absorption time. Bas ed on the difus ion eq uation of species, the concentration distribution within the droplet at ditierent times is computed. A solution for CO2 abso rption into a small water droplet is given.

A self-developed laser image measurement system was established to study the behavior of bubble formation at a single orifice in non-Newtonian Polyacrylamide (PAAm) solutions. The images of bubbles were captured by a CCD camera and the volumes of bubbles were digitally analyzed on-line. The effects of rheological property of PAAm solution, orifice, reservoir and gas flowrate on the bubble formation were studied experimentally. It is found that the bubble volume increases with the concentration of PAAm solution, the diameter of the orifice and the gas flowrate, respectively, whereas little effect by reservoir is observed in experiments.

The influence of the third component on gas-liquid mass transfer was studied by use of laser holographic interferometry. Four surfactants were added respectively and experimental results show that the microamount of surfactants can change obviously the concentration near the interface on bubble mass transfer process, which indicated that the third component has a significant effect on the bubble mass transfer process.

The diffusion of amino acids in aqueous solution was investigated experimentally by a holographic interferometric technique where the real-time holographic interference fringes indicating the concentration profiles of the liquid were obtained by an automatic photographing and memorizing program. The reliability of the instrument was verified by the measurement of the diffusion coefficient of KCl and sucrose in aqueous solution at 298.15K. Furthermore, the diffusion coefficients of glycine, L-alanine, L-valine, L-isoleucine, L-serine, L-threonine, and L-arginine in aqueous solution at 298.15K were measured, and the affecting factors of molecular structure and polarity were analyzed and discussed. In addition, on the basis of the Gordon model of the diffusion coefficient in the literature, a new semiempirical model was proposed to predict the liquid diffusion coefficients of amino acids in aqueous solutions. The equation parameters were fitted by the experimental data of seven amino acids in this work and four in the literature.