用压汞法计算冻干物料的表面分形维数

本文阐述了通过压汞测试获得冻干物料孔隙分布特性表面分形维数的方法,以冷冻干燥牛肉和火鸡肉为例计算了表面分形维数。研究表明:采用压汞法能够简便和合理地获得冻干物料的表面分形维数,可采用表面分形维数对冻干物料内部孔隙结构的粗糙和复杂程度特性进行定量描述;冻干物料的表面分维值主要与物料的孔隙分布特性有关,小孔的体积份额越大,物料的表面分形维数也越大。

Computation on Surface Fractal Dimension of Freeze-dried Product by Mercury Porosimetry

In order to characterize quantitatively the microstructure of freeze-dried material, the computational method of surfacefractal dimentsion through mercury intrusion is introduced. The surface fractals of freeze-dried materials, taking beef and turkeyfor examples, are calculated respectively. The results show that it is easy and reasonable to obtain the surface fractals of freeze-dried materials by mercury porosimetry, and surface fractals can be employed to characterize roughness and complexity of thepore distribution in freeze-dried materials. The surface fractal depends intimately upon the pore distribution of freeze-driedmaterial. The more the volume fraction of micro-pores in freeze-dried material is, the larger the surface fractal dimension will beobtained.