In this research, new ceramic BaFe 0.8 Ni 0.1 Cu 0.1 O 3-δ powder was synthesized by solid-state reaction method in conventional and microwave furnaces. Then, characterization, structure, and morphology of the resulting powders were studied. For characterization of synthetic powders, X-ray diffraction, powder density gas pycnometer method, particle size analysis, scanning electron microscopy, and energy-dispersive spectroscopy were performed. The results showed that the BaFe 0.8 Ni 0.1 Cu 0.1 O 3-δ powder synthesized in microwave furnace at 1,000°C without soaking time and in conventional furnace at the same temperature with 12-hr soaking time. In addition, the X-ray diffraction results demonstrated that the main peak is shifted to lower angles by substitution iron ions with nickel and copper ions. Furthermore, the crystal structures of powders were hexagonal and tetragonal, and their density were 5.88 and 5.43 g/cm 3 , respectively, in conventional and microwave furnaces. Finally, the morphology and particle size of the synthesized powders were the same in both furnaces.

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In this study the effects of adding silica and alumina nanoparticles on flow ability and compressive strength of cementitious composites based on Portland cement were investigated. In the first stage, the rheological behavior of different samples containing nanosilica, nanoalumina and polypropylene, polyvinyl alcohol and polyethylene fibers were evaluated. With increasing of nanoparticles in fresh samples, the slump flow diameter reduced. Fibers reduced the flow ability of the samples and viscosity increased. With increasing of the micro silica particles to cement ratio from 2/1 to 2/2, the slump flow diameter increased. By adding silica and alumina nanoparticles up to 3% and 2% respectively, the compressive strength increased and after decreased. Samples containing silica nanoparticles and fibers had the highest compressive strength.