For saturated samples, both oven an

For saturated samples, both oven and propanol dried, gel pores are found with dimensions of the order of 25 Å. However, for the capillary pores it is found that the pores of the oven-dried sample are of the order of 0.035 μm, which is almost twice the pore size of the propanol-dried sample, which is of the order of 0.015 μm.（干燥方式对凝胶孔没影响，但是对毛细孔有影响）. The preparation of the dry samples, oven dried or propanol dried, has a large influence on the microstructure. These measurements also show that pores collapse during oven drying, resulting in a larger fraction of capillary pores. Therefore, oven-dried samples have a faster water absorption than propanol dried samples.