Infrared drying technology (IFD)decreases the nanoparticles aggregation in the process of drying ultrafine powders by a Sol - Gel method. The sample is characterized by XRD,BET,TEM. The experimental results indicate that, compared with supercritical fluid drying(SCFD), IFD contributes a significant effect to drying nanoparticles. Meanwhile, this method is a low - cost and environmentally friendl...