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In this work, electrophoretic deposition (EPD) was applied to obtain novel hydroxyapatite (HAP)/lignin (Lig) biocomposite coatings on titanium substrate. Nanosized hydroxyapatite powder, prepared by using the modified chemical precipitation method, was used for the fabrication of HAP/Lig composite coatings. EPD was performed at different values of constant voltage and constant deposition time. It was confirmed that control over deposited mass can be achieved by applied voltage and time. The uniform and compact coatings were successfully deposited at applied voltage of 60 V in various deposition times lower than 1 minute. The effect of lignin as natural non-toxic polymer on microstructure, morphology and thermal behavior of biocomposite HAP/Lig coatings was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The electrophoretically deposited HAP/Lig coating has been successfully sintered at lower sintering temperature of 900°C, producing non-fractured coating and indicating that lignin may exhibit adhesive role, strengthening the bonding between HAP particles and substrate surface.

Polycrystalline samples of the new semimagnetic semiconductor (x = 0.06, 0.12, 0.25, 0.39, 1.00, 1.40, 1.80) were obtained by ceramic technology. An x-ray diffraction experiment was performed on all of the samples at room temperature. These data provided the basis for Rietveld refinements. The refinements showed that ions preferentially occupy the 24d position. The lattice constants and the mean cation - anion distances decrease linearly with the -ion concentration. The inverse magnetic susceptibilities for all of the samples depend linearly on the temperature for . In this region only the lowest Kramer's doublet is populated, and for that level the effective magnetic quantum number is deduced. The Curie - Weiss paramagnetic temperatures obtained from the low-temperature region depend linearly on the concentration x. Over the whole experimental region , the magnetic susceptibility deviates from the Curie - Weiss law, and its calculation requires inclusion of the first excited Kramer's doublet. The effective magnetic quantum number and energy gap of the first excited doublet were deduced.

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