Sharif Digital Repository

A new and effective hot milling system was designed and applied to the synthesis of PbZr0.95Ti0.05O3 (PZT) powder. PbO, ZrO2 and TiO2 powders were used as starting materials and hot milled at various temperatures ranging from 10 ̊°C to 800 ̊°C. The obtained powders were characterized by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). Results indicated that pure, crystalline, and fine PZT powders with the average particle size of 170 nm can be successfully synthesized directly after a relatively short synthesis time of 12 h at lower temperature of 800 ̊°C by the hot milling technique. In contrast to this method, this study demonstrates that conventional solid-state... 

In this research, an attempt was made toward synthesizing a sol–gel–based silica aerogel and its subsequent coating on a copper wire by phase separation of polystyrene. Adaption of this new approach enabled us to coat the metallic wire with powder materials. The use of this method for coating, led to the formation of a porous and thick structure of silica aerogel. The coated wire was placed in a needle and used as the sorbent for in–tube solid phase microextraction of chlorobenzenes (CBs). The superhydrophobicity of sorbent on extraction efficiency was investigated by using different ratios of tetraethylorthosilicate/methyltrimethoxysilane. The surface coated with the prepared silica aerogel...