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Nano-sized mullite was synthesized by mechano-chemical, sol-gel/milling, process. Aluminum nitrate and tetraethyl ortho silicate were used as precursors to prepare the single phase gel. The prepared gel was subjected to intense mechanical activation using a planetary ball mill prior to annealing. DTA/TGA results showed that mullitization temperature significantly decreases due to mechanical activation as mullite starts to form at 1094°C in unmilled sample whereas intermediate milling for 20 hours decreases this temperature to 988°C. Also, mullite formation occurs at 1021 and 1003°C for samples milled for 5 and 10 hours, respectively. SEM results showed that the morphology of the products was altered by the intermediate mechanical activation. Calculation of the mullite crystallite sizes indicated that they were indeed in nano scale and this result was confirmed by TEM investigations which shows the mean crystallite size of 70 nm.

Nano size particles of barium hexaferrite were produced by conventional mixed oxide ceramic method from BaCO₃ and αFe₂O₃ as starting materials with a Fe/Ba molar ratio of 11. The mixture of precursors was intensively milled by high energy ball mill and the The influence of various process control agents (PCA) on the process has been investigated. Analysis of the XRD patterns indicates that PCA can strongly alter the morphology and phase composition of ball milled powder particles. In all milled samples, BaCO₃ completely decomposed and slight displacement of reflections of hematite phase due to the dissolving of various ions like Ba or C in its lattice is observed. Nano size particles exhibiting angular shape together with some amorphous structure were observed in the sample processed in the presence of NaCl. Barium hexaferrite magnetic phase was partially formed in sample milled in the presence of stearic acid.

The single-phase nanostructure forsterite powder was successfully synthesized by mechanical activation of talc and magnesium carbonate powder mixture followed by annealing in the presence and absence of ammonium chloride. Mechanical activation was used as an efficient method for the optimization of powder properties by means of combination and uttermost homogenization of the powder mass. Besides, the presence of chlorine ion affected the forsterite formation rate via producing smaller particle size during subsequent annealing which is very important in the case of diffusion-controlled reactions. The single-phase nanostructure forsterite powder with crystallite size of about 36 nm was successfully synthesized by 10 h mechanical activation with subsequent annealing at 1000°C for 1 h. While in the presence of chlorine ion, the single-phase nanostructure forsterite powder with crystallite size of about 20 nm could be obtained by 5 h of mechanical activation with subsequent annealing at 1000°C for 2 min.

A mechanism for rapid, single-step synthesis and fabrication of intermetallic compounds having brittle–ductile ingredients at low temperature is suggested. Employing this mechanism, highly pure, dense Mg₂Si pellets were obtained using silicon nanoparticles and micron-sized magnesium particles as starting materials. Silicon nanoparticles chop magnesium particles and produce highly-activated mixture through a planetary ball-milling. Magnesium/silicon interface increases by increasing dispersity of silicon nano-particles in magnesium. Consequently, final product was prepared only by consolidation at 300^∘C for 5min without any post-treatment. The pure phase of Mg₂Si with grain sizes about 200nm and with no evidence of presence of MgO was achieved. The Seebeck coefficient, electrical and thermal conductivity were measured to be $-$220 $\mu$VK${}^{-1}$, 72 ${\mathrm{\Omega }}^{-1}$cm${}^{-1}$ and 3.48Wm${}^{-1}$K${}^{-1}$ at 823K for nondoped Mg₂Si, indicating that this method does not degrade the properties of the product, despite the fact that fabrication is performed rapidly and at low temperature.

The solid solutions of the (1-x)Na${}_{0.5}$Bi${}_{0.5}$TiO₃-xNa${}_{0.5}$K${}_{0.5}$NbO₃ system were produced by the conventional ceramic technology using mechanical activation of the synthesized product. It was found that in the (1-x)Na${}_{0.5}$Bi${}_{0.5}$TiO₃-xNa${}_{0.5}$K${}_{0.5}$NbO₃ system at room temperature, a number of morphotropic phase transitions occur: rhombohedral → cubic → tetragonal → monoclinic phases. The introduction of a small amount of Na${}_{0.5}$K${}_{0.5}$NbO₃ leads to an increase in the temperature stability of the dielectric properties of ceramics. A change in the relaxor properties of the solid solutions of the (1-x)Na${}_{0.5}$Bi${}_{0.5}$TiO₃-xNa${}_{0.5}$K${}_{0.5}$NbO₃ system was shown. The increase in energy density and energy efficiency was found at additive 10mol.% of Na${}_{0.5}$K${}_{0.5}$NbO₃.

A mixture of silicon carbide nano-particles and nano-whiskers has been synthesized through solid state reduction of silica by graphite employing high energy planetary ball milling for 25 h and subsequent heat treatment at 1300-1700°C in dynamic argon atmosphere. Effects of process conditions on the thermal behavior, phase composition and morphology of the samples were investigated using DTA/TGA, XRD and SEM, technique, respectively.

DTA/TGA analysis shows that silicon carbide starts to form at ~ 1250°C. Analysis of the XRD patterns indicates that the phase composition of the sample heat treated at 1300°C for 2 h mainly consists of SiO₂ together with small amount of β-SiC. Nano-crystalline silicon carbide phase with a mean crystallite size of 38 nm was found to be dominate phase on heat treatment temperature at ~ 1500°C. Substantial SiO₂ was still remained in the above sample. SEM studies reveal that the sample heat treated at 1500°C for 2 h contains nano-particles and nano-whisker of β-SiC with a mean diameter of almost ~ 85 nm. The results obtained were also showed that the characteristics of the synthesized SiC particles strongly depend on the mechanical activation and heat treatment conditions.

Higher environmental standards have made the removal of toxic metals such as hexavalent chromium from wastewater; an important problem for environmental protection. Iron oxide is a particularly interesting adsorbent to be considered for this application.

In this study, a new method combining adsorption and magnetic separation was developed to remove Cr(VI) from wastewater. The nanocrystalline magnetite as adsorbent was produced via thermo- mechanical reduction of hematite. Various parameters which affect the adsorption of Cr(VI) such as time, pH, temperature and initial concentration were investigated using thermo-gravimeters (TG), X-Ray diffraction (XRD), scanning electron microscopy (SEM) and atomic adsorption spectroscopy (AAS) techniques. The maximum adsorption was occurred at pH 2. The adsorption data were fitted well to Langmuir isotherm model. The adsorption of Cr(VI) increased significantly with increasing of temperature and time.