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Recent investigations suggest that forsterite ceramics possess good biocompatibility and mechanical properties and might be suitable for potential application like bone implant material. In this study, nanocrystalline forsterite (Mg₂SiO₄) powder was prepared by mechanochemical method and subsequent heat treatment and the effect of fluorine ion as catalyst was studied. Mechanochemical process and heat treatment were done on the MgCO₃, SiO₂ and (NH₄)₂SiF₆ powders. The synthesized powders were characterized by X-ray diffraction (XRD), thermogravimetric (TG) analyses and scanning electron microscopy (SEM). The synthesized nano-powder had particle size smaller than 100 nm. The crystallite size of powders after 5 hours mechanical activation was 18 nm. Mechanical activation in the presence of fluorine ion affects the mechanism of forsterite formation and increase the rate of decomposition of MgO and fabrication of forsterite.

In this study, the effects of the molarity of the precipitating agent on the synthesis of nanostructured NiFe₂O₄ powders by coprecipitation, followed by calcination were investigated and its optimum amount was also determined. Ni-ferrite powder was synthesized for the first time by dissolving Fe and Ni chlorides and ammonium ferrous sulfate in deionized water with different molar proportions. While stirring, the precipitating agent of NaOH was added to the solution with different molarities and after 1 hour of aging, the resultant precipitate was washed with deionized water and acetone.

It was concluded that single phase nickel ferrite nanocrystalline powders can be prepared by use of 2.2M NaOH, with crystallite size of 30-50 nm.

Doped zinc oxide nanopowder was synthesized by combustion method. The as-synthesized nanopowder was spray dried with three different (20, 25, 30) percentage of solid contents. Sintered samples were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) showing the presence of secondary phases at intergranular spacing. The electrical behavior of the sintered samples was studied on the basis of the current density versus electric field (J–E) characteristics. A comparison on the electrical and microstructural properties of the varistors obtained by nanopowder and its spray dried granules was made. The best results on these characteristics were achieved through the spray drying route, obtaining a nonlinear coefficient of 167 and breakdown field of 8182 Vcm^-1 at a sintering temperature of 900°C.

Nano-sized nickel hydroxide powder has been synthesized by complexation-precipitation method through various decomposition routes in order to investigate its effect on textural and structural characteristics of the nickel hydroxide products. The products were then characterized by various analytical techniques such as XRD, SEM, ICP and FTIR. The results showed that the product with different size, shape and structure could be obtained by using different routes for decomposition of the complex.

In this research Sr-hexaferrite powder was synthesized by a sol–gel auto-combustion route using two different fuels (glycine and citric acid) and two different basic agents (ammonia and trimethylamine). N-decyltrimethylammonium bromide (C₁₃H₃₀BrN) was also employed as a cationic surfactant. The results showed the finest crystallite size and the lowest calcination temperature have been obtained as 27.2 nm and 800 °C respectively, in the presence of citric acid, trimethylamine and surfactant.