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The calcium phosphate spherical material with a hierarchical structure has been used as a bone implantation material. To improve the properties of the implant material, the compositions of calcium phosphate, silicon, and titanium are crucial. The presence of silicon on the surface of the phosphate–calcium material accelerates the bonding of the implant with the bone (osseointegration). The aim of this work was to develop a sol–gel method to prepare spherical calcium-phosphate@TiO 2 –SiO 2 biomaterials for bone implantation. The CaO@TiO 2 –SiO 2 biomaterial with a core–shell structure was synthesized by the sol–gel method. The biological properties of the materials were studied with a simulated body fluid (SBF). The sample had a spherical shape. The sample exhibited bioactive properties because an increase in the content of calcium and phosphorus ions in the shell and the presence of precipitated ions from the solution were detected on the surface. The TiO 2 –SiO 2 framework was uniformly fixed on the CaO core. Heat treatment of the hybrid mesostructure led to the formation of mesoporous materials with a specific regular structure in the nanometer size in the shell, which is necessary for the fixation of biological cells when the sample is introduced into the biological medium. The formation of a calcium–phosphate layer on the materials and the release of soluble silicon and calcium ions into the SBF are the key factors for the rapid connection of these materials with tissue. The results demonstrate that the CaO@TiO 2 –SiO 2 biomaterial with a core–shell structure is a good candidate for bone implantation.

Nanocrystalline CeO2 shows intriguing electroheological performance.

Thin films and dispersed products in the system SiO 2 -P 2 O 5 with phosphorus oxide molar content from 0 to 30% have been obtained by the sol-gel method from film-forming solutions based on tetraethoxysilane and phosphoric acid, ethyl alcohol, and water. The variations of the rheological properties in successive states of the solution -sol-gel system are established. The physical -chemical processes in solution with deposition on a substrate and with heat-treatment of the product are investigated. IR spectroscopy and atomic-force microscopy are used to study the structure and physical -chemical properties of the films and disperse products obtained.The sol-gel technology is being increasingly used to obtain oxide ceramic, glass ceramic, and glassy materials. This method for synthesizing materials in oxide systems makes it possible to extend the boundaries of the glass-formation zone and, correspondingly, the composition range for practical applications [1, 2]. Silicophosphate glasses, both binary and polycomponent, conventionally are used to obtain optical media, and in recent decades in other areas also [3 -5]. The production of silicophosphate glasses by the conventional melting of the initial materials together is a laborious process that is difficult to control, which results in uncertain composition and instability of the properties of the glass produced. At the same time, it is precisely the sol-gel methods of synthesis, specifically, of bioglass, together with the technological advantages that has a positive effect on the bioactive properties of the materials obtained [6].The purpose of the present work was to obtain materials in the system SiO 2 -P 2 O 5 with phosphorus oxide content from 0 to 30% 2 by the sol-gel method and to investigate their structure and physical -chemical properties.The materials were obtained in a finely dispersed powder state and in the form of films from film-forming solutions (FFS). They were prepared on the basis of 96% analytically pure (AP) ethyl alcohol, AP tetraethoxysilane (TEOS), and AP orthophosphoric acid with solution concentration 0.4 moles/liter. The films were obtained on different amorphous and crystalline substrates by centrifuging with rotational speeds 4000 rpm or drawn at the rate 5 mm/sec followed by heat-treatment at different temperatures. The powder materials were obtained by dryng FFS after they were completely aged.The physical -chemical processes occurring in the solutions and during treatment of the products obtained from them were studied be means of viscosimetry (VPZh-2, temperature 25°C), IR spectroscopy (Perkin Elmer "Spectrum One"), and mass-spectrometric analysis. The thermal analysis of the thin-film systems was performed on a setup using microbalances based on a piezoelectric resonator with weighing accuracy 10 -8 g. Atomic-force (Solver P47) and electron (Phillips SEM 515 scanning electron microscope) microscopy were used to study the composition and structure of the films. The index of refraction and the thickness of the films were measured w...

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