高于胶凝临界温度直链淀粉分子分形

应用动态光散射技术,研究直链淀淀粉水溶液在高于胶凝临界温度条件下驰豫谱化的规律,发现动态光散射驰豫谱经历了指数衰减及随后的非指数衰减（慢模）两种模式,对于快模,可用大分子链串滴运动解释,对于慢模,则可用分形构象下的反常扩散加以解释。此外,还测量了直链淀粉水溶液在不同温度、不同浓度下的分维,发现直链淀粉分子符合自避无规行走模型,分维等于１．６７,且随样品浓度、温度的变化而略有变化。

Fractal Property of Amylose Molecules at a Temperature above Critcial One of Gelation

The evolution of relaxation spectrum of aqueous amylose solution at a temperature higher than critical temperature of gelation is studied by applying dynamic light scattering. The relaxation spectrum under the action of dynamic light scattering is found to go through exponential decay and subsequent non exponential decay known as fast mode and slow mode respectively. The fast mode can be explained by bolb motion of macromolecule chains; while the slow mode, by anomalous diffusion under fractal conformation. In addition,the fractal dimension of aqueous amylose solution is measured at different temperature and different concentration of sample. The amylose molecules are found to be in conformity with a self avoiding and irregular walking model, of which the fractal dimension equals to 1.67 and slightly changes with the change of temperature and concentration of samples.