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Composite biomaterials, like calciumphosphate/bioresorbable polymer, offer excellent potential for reconstruction and reparation of bone tissue defects induced by different sources. In this paper synthesis of calciumphosphate/poly-DL-lactide-co-glycolide (BCP/DLPLG) composite biomaterial formed as filler and blocks was studied. BCP/DLPLG composite biomaterial was produced in the form of spherical granules of BCP covered by a DLPLG layer, average diameter of 150-250 mu m. By cold and hot pressing of granules at up to 10000 kg/cm(2), blocks with fine distribution of phases and porosity up to 3% were obtained. Characterization was performed by wide-angle X-ray structural analysis (WAXS), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), infrared spectroscopy (IR), and mechanical properties by defining the compressive strength. In vitro citotoxicity research was carried out on cellular cultures of fibroblasts of human (MRC5) and mouse (L929). In vivo research was performed in two steps. Reparatory ability of BCP/DLPLG in mice was examined in the first step, and then bone tissue reconstruction possibilities on 10 patients in the next step. In vitro tests showed very good fibroblast adhesion and non-citotoxicity of the composite. A material is considered non-cytotoxic if the cell survival is above 50%, and in our case it was 90%. In vivo research on mice indicated high level of reparatory ability of this composite with formation of new bone and vascular tissue six weeks after reparation. Application of this composite for healing infrabone defects of patients showed a high level of osseous regeneration.

ZnO varistors with non-linearity coefficients reaching 50 and low values of the leakage current (similar to0.01 A/m(2)), were obtained by a method referred to as "direct mixing of constituent phases". The method is based on sintering of a mixture of the constituent phases with the following compositions: ZnO phase uniformly doped with Co2+ and Mn2+; intergranular phase: gamma -Bi2O3 stabilized with Mn2+ or Zn2+; spinel phase: Zn1.971Ni0.090Co0.030Cr0.247Mn0.090Sb0.545O4 AS proved, the obtained varistors are composed of the same phases as those introduced into the system. The influence of composition as well as milling and sintering parameters on the varistor characteristics were investigated. Some varistor powder mixtures were intensively milled before sintering. As a result, high density ceramics with higly homogeneous microstructure were obtained after sintering.

The method of directed synthesis of the constituent phases (DSCP) was applied to investigate the influence of spinel phase composition on characteristics of ZnO varistors. Six varistor mixtures differing only in chemical composition of the spinel phase were prepared. The phase ratio as well as the compositions of ZnO and intergranular gamma-Bi2O3 phases were the same in all samples. Characterization of prepared varistors was performed by X-ray diffraction, SEM and electrical measurements. It was shown that it is possible, in certain cases, to estimate additive redistribution taking into account changes in lattice constants of ZnO, spinel phases and varistor composition. Comparison of six different raristor mixtures shows that it is possible to reduce the number of components of the system if all main constituents of the varistor microstructure are still present. Results confirmed advantages of the DSCP method in preparation of varistors of required phase composition and properties.

TiO2 and ZnO thin films were prepared by dip-coating method from TiCl4, and Zn(NO3)(2) precursor solutions, respectively. Basic parameters of the process such as temperature of thermal treatment, heating and cooling regimes, and number of cycles required for obtaining uniformly coated substrates were defined. Microstructural analysis showed that at least 20 cycles must be repeated to obtain a completely covered substrate and continual film of TiO2 at 823 K. In the case of TiO2 film thermally treated at 723 K even n=30 was not enough to produce a continual film. Preparation of continual film of ZnO requires at least n=22, at 773 K. Microstructure and roughness of the prepared films were investigated by AFM method.