水合生物大分子体系恒温冻结过程中水的扩散机制初探

AN APPROACH TO THE DIFFUSION MECHANISM OF HYDRATION WATER IN BIOPOLYMERS DURING ISOTHERMAL FREEZING BELOW GLASS TRANSITION TEMPERATURE

本文详细讨论了张极震等人对水合生物大分子体系恒温冻结过程的研究结果,结合反常扩散理论,提出了一个广义的JMA转变方程.用这个方程可以比较好地解释Avrami指数反常的原因,并得到这种体系在恒温冻结过程中水的扩散机制.

This paper deals with the freezing behaviour of hydration water in biopoly-mers reported by Zhang Ji-Zhen et al. The influence of fusion heat of hydration water and of dilute heat on Avrami exponent are discussed. According to the theory of anomalous diffusion, we propose a generalized JMA equation of phase transformation with which the anomaly of Avrami exponent can be interpreted. In addition, the Avrami exponent in our generalized eqution has a new physical implication.