TY - GEN
T1 - Fractal characteristic of silica xerogels with different additives
AU - He, Fei
AU - He, Xiaodong
AU - Li, Yao
PY - 2006
Y1 - 2006
N2 - Two step acid-base catalyzed silica xerogels which had integrated structure were prepared through sol-gel and ambient pressure drying. Silica xerogels powder, TiO2 powder and short fibers were added as the additives in order to improve the properties of silica xerogels. The porous structure was estimated by the means of nitrogen adsorption method and mercury intrusion porosimetry (MIP). According to the results of these two experiments, the surface fractal dimensions were calculated using Frenkel-Halsey-Hill (FHH) method, Menger sponge model and thermodynamic correlations respectively. The difference among them was compared and the influence of additives for pore structure also was analyzed combining with the fractal dimensions. The fractal dimensions exhibit the degree of surface roughness. The strength of silica xerogels is increased by adding the additives, and the shrinkage is also restrained in the course of drying. The fractal dimensions calculated from FHH method and thermodynamic correlations have almost same tendencies. These two models are more appropriate to analyze the porous fractal structures than Menger sponge model.
AB - Two step acid-base catalyzed silica xerogels which had integrated structure were prepared through sol-gel and ambient pressure drying. Silica xerogels powder, TiO2 powder and short fibers were added as the additives in order to improve the properties of silica xerogels. The porous structure was estimated by the means of nitrogen adsorption method and mercury intrusion porosimetry (MIP). According to the results of these two experiments, the surface fractal dimensions were calculated using Frenkel-Halsey-Hill (FHH) method, Menger sponge model and thermodynamic correlations respectively. The difference among them was compared and the influence of additives for pore structure also was analyzed combining with the fractal dimensions. The fractal dimensions exhibit the degree of surface roughness. The strength of silica xerogels is increased by adding the additives, and the shrinkage is also restrained in the course of drying. The fractal dimensions calculated from FHH method and thermodynamic correlations have almost same tendencies. These two models are more appropriate to analyze the porous fractal structures than Menger sponge model.
KW - Fractal dimension
KW - Mercury intrusion porosimetry
KW - Nitrogen adsorption method
KW - Silica xerogels
UR - https://www.scopus.com/pages/publications/46149092255
U2 - 10.1109/NEMS.2006.334713
DO - 10.1109/NEMS.2006.334713
M3 - 会议稿件
AN - SCOPUS:46149092255
SN - 1424401402
SN - 9781424401406
T3 - Proceedings of 1st IEEE International Conference on Nano Micro Engineered and Molecular Systems, 1st IEEE-NEMS
SP - 1272
EP - 1275
BT - Proceedings of 1st IEEE International Conference on Nano Micro Engineered and Molecular Systems, 1st IEEE-NEMS
T2 - 1st IEEE International Conference on Nano Micro Engineered and Molecular Systems, 1st IEEE-NEMS
Y2 - 18 January 2006 through 21 January 2006
ER -