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Luminescent nano-pigments based on strontium aluminates doped with various amounts of europium rare earth ion (Sr 4 Al 14 O 25 :Eu 2? ) were synthesized by solution combustion method which involves the exothermic reaction of an oxidizer and an organic fuel. It is a suitable method for producing chemically homogenous and pure powders with very fine particle size. Phases studies by X-ray diffractometer indicated formation of pure phase Sr 4 Al 14 O 25 with crystallite sizes about 52.46 nm and peak shift of about 2h = 0.26°due to Eu 2? doping. scanning electron microscope micrographs also revealed that the particles have irregular morphology and wide particle size distribution. The emission spectrum showed main emission peak at about 480 nm. Energy transfer mechanism between the two emission centers and the effect of Eu 2? ion concentration on emission spectrum was studied and it was deduced that the maximum emission intensity occurred at 4 at% of Eu 2? . Absorption spectrum of the samples were lower than 0.5 %, especially in emission region of the doped pigments.

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In this research work, hydroxyapatite/alumina/YSZ bio nanocomposite coatings on titanium substrate were created by electrophoretic deposition (EPD) and reaction bonding process. By using the EPD process, uniform green form coatings containing HA, yttria-stabilized zirconia (YSZ), and aluminum particles were produced on titanium. After oxidation of aluminum at 660°C and sintering at 850°C, a dense and adherent HA/Al O /YSZ coating was produced. Scanning electron microscopy, X-ray diffractometric and mechanical tests were employed to investigate the morphologies, compositions, hardness, toughness and bonding strength of the coatings. The corrosion studies and cell culturing experiment were carried out and the results show that the HA/YSZ/Al O coatings are more bioactive and more resistance to corrosion than HA coatings. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1916-1922, 2018.