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Mechanochemical synthesis of TiO₂ by using the simple laboratory scale nutating centrifugal ball mill was demonstrated for the first time. In our prototype, the nutation angle in the range of 0–20 deg, besides the speed of rotation of central axes up to 1400 rpm, can be adjusted independently. In order to compare the milling efficiency between Nutator and high-energy planetary ball mill TB-2, the soft mechanochemical reaction between TiOSO₄ ⋅ ₂H₂O and Na₂CO₃ has been studied. In the case of nutating mill the intensity of diffractions corresponding to TiOSO₄ ⋅ 2H₂O and Na₂CO₃ completely disappeared after 5 min milling. In case of the planetary ball mill TB-2, due to the large difference in the centrifugal forces (60g vs 20g), mechanochemical treatment for 1 min leads to similar results and after 10 min, the sample contains mainly rutile TiO₂ with trace of TiO₂-II.

A new mechanism of solid-state reactions, based on a mass transfer process due to the plastic deformation is proposed. By the example of the nucleation in the course of the mechanosynthesis of complex oxides, there has been demonstrated a role of twinning processes in the nucleation of spinel (MgAl₂O₄), lead titanate (PbTiO₃) and yttrium-aluminum garnet (Y₃Al₅O₁₂) under grinding the powders of MgO + Al₂O₃, TiO₂ + PbO and Al₂O₃ + Y₂O₃, respectively. It has been proposed that the mechanical twinning is the main mechanism of mechanochemical solid-state reactions.

Interpretation of the mechanochemical aspect from the viewpoint of the manifestation of P. A. Rebin-der effect is proposed on the basis of the experimental investigation of the kinetics and mechanism of the processes taking place during chemical mechanical polishing semiconductors, dielectric and metal crystals. The possibility of the tribochemical activation of chemical reactions by the flow of liquid silica sols under the joint action of chemical mechanical factors on the surface is demonstrated. It is established that solid particles promote activation and localization of chemical reactions on the surface of crystals on the atomic scale, and removal of the products of chemical reactions in the nanoscale. As a result, a mirror-smooth surface with subnanosecond relief is formed; containing no micro and nano scratches, pits, etched regions and other microdefects.

The synthesis of lead ferroniobate from lead, iron and niobium oxides taken in the stoichiometric ratio was investigated for the purpose of choosing the optimal compositions, conditions of mechanical activation and subsequent thermal treatment. The process was carried out in the presence of the excess of lead oxide to prevent the deviation from the stoichiometry of the ceramics obtained after sintering. The changes of the phase composition of mixtures during mechanical activation and subsequent thermal treatment were followed. It was demonstrated that the most attractive structure and properties are those characterizing lead niobate obtained with some excess of lead oxide over the stoichiometric composition. It was established that with the help of mechanical activation it is possible to vary within a broad range the temperature of the magnetic phase transition for the powders and ceramics of lead ferroniobate.

With the use of solid-phase synthesis in an extruder, chitosan and L,D-lactide grafted copolymers were obtained. A mechanism of graft polymerization was proposed, an effect of process conditions exerted on the yield and structure of the target products was studied. Based on the data obtained from fractionation, IR spectroscopy and study of the elemental composition of the fractions, a substitution level has been calculated for the chitosan amino groups that were 0.19–0.41. An average polymerization level for lactide in grafted chains and an effect exerted by the grafting on the solubility of chitosan and physico mechanical characteristics of film materials were determined. Based on the copolymers synthesized, three-dimensional matrices have been obtained for tissue engineering (macroporous hydrogels, spherical microparticles), as well as compatibility and biodegradation rate have been estimated for the materials.

Features of the formation of macro and microstructural state and the phase composition of Cu–30 vol. % Fe₃C nanocomposites obtained by mechanical alloying of copper and iron powders in the liquid source of carbon (xylene) followed by thermal treatment were studied by means of X-ray phase analysis, Mцssbauer spectroscopy, scanning electron and optical microscopy, measurement of dynamic magnetic susceptibility. It was demonstrated that iron carbides are not formed during alloying; however, for the alloys obtained by grinding for 96 h, annealing at a temperature above 500 °С leads to the formation of cementite with the volume fraction of about 30 %. The grain size of the copper matrix of this composite is 10 nm, while after annealing at 800 °С it is 30 nm.

Geopolymerisation behaviour of Imperial Smelting Furnace (ISF) Zn slag and granulated Cu–Ni slag, mechanically activated in air and in CO2 atmosphere (P = 10⁵ Pa) has been studied by XRD, SEM, FTIR, and isothermal conduction calorimetry. Mechanical activation of the slags has been carried out in a centrifugal-planetary mill AGO-2. Geopolymer samples have been prepared by mixing of the mechanically activated slag powders with NaOH solution or liquid glass and curing at (20±2) ^oC for up to 180 days. It has been observed that the ISF Zn slag and the granulated Cu–Ni slag are suitable for the synthesis of building materials through geopolymerisation. The effect of milling atmosphere on properties of geopolymers is found to be alkaline reagent specific. A suitable combination of the milling atmosphere and alkaline reagent is required to realize the beneficial effect on mechanical properties of the geopolymer.

The introduction of α-Al₂O₃ nanoparticles into the gel formed during the hydrolysis of aluminium nitrate causes a substantial decrease in the temperature of its transition tino thermodynamically stable modification. The higher is the concentration of seeding within the range 0.2–5 mass %, the lower is the temperature of the formation of monophase α-Al₂O₃. At the sme time, the temperature of phase transition into the α-modification depends on the method of introduction of the seeding into the gel. This may be connected with nonuniform distribution of nanoparticles over its volume. The use of deionized water as a solvent instead of distilled water allows decreasing the temperature of α-Al₂O₃ formation to 500 °C. Due to the low temperature of the formation of a-phase (<950 °C), the product consists of easily destroyable granules formed by nanoparticles 45–60 nm in size. Nevertheless, the samples formed from powders with close size demonstrate different sintering ability during low-temperature annealing in the air (1300 °C). Their densities vary within the range 67–97 % of the theoretically possible value. This is likely to be connected with the fact that separate particles in granules get grown together under unfavourable conditions.

Mechanically activated composites of betulin diacetate and dipropionate with water-soluble natural polysaccharide arabinogalactan were obtained. It was established that the composites are characterized by increased concentration of betulin diacyls during their dissolution in water. The formation of molecular complexes of betulin diacetate and dipropionate with arabinogalactan during mechanical activation and during the dissolution of initial and mechanically activated mixtures in water was assumed. The complexes of betulin diacyls with arabinogalactan were also obtained in the form of thin films, readily soluble in water.