Composite materials with a two-layer coating consisting of ultrahigh molecular weight PE and a lower molecular weight PE are synthesized on the surface of filler particles (Al2O3/ultrahigh molecular weight PE/lower molecular weight PE) using the polymerization filling technique by the sequential two-step polymerization of ethylene. In the composites, the ratio ultrahigh molecular weight PE : lower molecular weight PE (polyethylene) is varied with the molecular weight of PE being constant or the molecular weight of PE is varied with the ratio ultrahigh molecular weight PE : lower molecular weight PE being constant. In this case, the lower molecular weight PE is the external layer on the surface of composite particles, while the ultrahigh molecular weight PE occurs directly on the surface of filler particles. In both cases, with an increase in the fraction of polyethylene in the two-layer coating in pressed composites, the degree of crystallinity increases and the lamella parameters change. The mobility of polymer chains in the intercrystalline amorphous layer alters. Creation of two-layer coatings ultrahigh molecular weight PE/lower molecular weight PE allows modification of the deformation–strength properties of the composites. An increase in the content of polyethylene in the composites is accompanied by a considerable increase in the elongation at break and the elastic modulus of the composites while the breaking stress decreases.

The effect of the synthesis method on the formation of the structure and composition of composites produced by the deposition of lanthanum oxide compounds on porous alumina is studied. The effect of the morphology of porous alumina (α-modification) on the formation of various compounds (La 2 O 3 oxide, as well as LaAlO 3 and La 10 Al 4 O 21 aluminates) during the thermal treatment of a support impregnated with a solution of lanthanum nitrate is shown. It is found that when systems are treated in a water fluid (WF), the processes of structuring and phase formation proceed at a much lower temperature and more intensely than during the thermal treatment, which is due to the mobility of the structural elements in the hydrated state. It is shown that the formation of LaAlO 3 aluminate is limited by the hydration of the initial aluminum oxide, which proceeds more intensely in the case of its γ-modification. Varying the sequence and conditions of the stages of the treatment in a WF and the thermal treatment makes it possible to obtain composites that have different morphologies and contain various oxide compounds and phases.

Low valence bismuth cationic centers were introduced into hydrogen forms of ZSM-5 and mordenite zeolites via impregnation of zeolites in aqueous solution of bismuth salts and subsequent reductive solid state ion exchange (SSIE). It has been found that Near IR photoluminescent bismuth monocations Bi+ and cluster ions are formed in the exchange positions and their optical properties in ZSM-5 and mordenite depend mainly on a zeolite Si/Al ratio and, to a lesser extent, on the amount of loaded bismuth. The photoluminescence emission and excitation spectra of bismuth cationic species (monocations or clusters) are markedly different in ZSM-5 and mordenite. This difference can be explained, taking into the account, that extraframework (exchanged) cations in mordenite zeolite, unlike ZSM-5, can occupy only several distinct positions relative to the mordenite framework structure.

Samples of (0.5–15)%CoO/CeO2, Co3O4, and CeO2 have been studied in the oxidation of CO to CO2 in a CO+O2+H2 mixture in a range of 40–340°C. The highest activity in CO oxidation is exhibited by 10%CoO/CeO2 with a characteristic conversion of CO to CO2 of γ50 = 50% at Т50 ≈ 140°С and γ ≈ 100% at Т = 180–220°С. The СО2 yield decreases at 220–240°C due to competition for oxygen in the CO and H2 oxidation reactions; at Т > 240°C, it decreases due to the consumption of CO in the methanation reaction. According to XRD and H2-TPR, cobalt oxide in the 10%CoO/CeO2 sample is present in two forms of a highly dispersed Co3O4 oxide (CoxOy clusters) interacting with the support and in the form of a Co3O4 phase. Carbon monoxide oxidation in a range of 60–180°C occurs on CoxOy clusters. Under these conditions, the activity of particles of the Co3O4 phase in pure oxide and the 10%CoO/CeO2 catalyst is lower than that of the clusters. The effect of the properties of adsorption complexes formed involving the oxygen contained in the clusters and in the gas phase on the temperature dependence of CO conversion has been studied.

Polycrystalline samples of rubidium magnesium cyclotriphosphate RbMgP3O9 phase were prepared by crystallization from the melt. It was shown, that reductive conditions throughout crystallization process lead to the appearance of strong photoluminescence in the Near-IR. The photoluminescence spectrum contains the single band with maximum at 913 nm (300 K), while photoluminescence excitation spectrum consists of five bands in visible spectral diapason. The kinetic of photoluminescence decay after the pulse excitation can be fitted by single exponent with characteristic lifetime 525 mu s (300 K). We suppose, that univalent bismuth cation Bi+, substituted for Rb+, is the single Near-IR emissive center in RbMgP3O9 phase. This material and the similar bismuth-doped cyclotriphosphate phases can be the new optical materials with potential applications in photonics and laser physics.

The 5% CuO/Ce1 – xPrxOy catalysts were synthesized on the basis of CeO2 and PrO2 oxides and Ce1 – xPrxOy solid solutions with x = 0.2, 0.5, and 0.8. Highly dispersed copper oxide was present in the 5%CuO/Ce1 – xPrxOy catalysts. Upon interaction with the support, it formed active oxygen, which participated in CO chemisorption and a low-temperature reaction of CO oxidation in the presence of hydrogen. The highest conversion of CO in an excess of H2 (γmах(Т)), which was close to 100%, was obtained at temperatures of 120–160°C on a 5% CuO/CeO2 catalyst. Upon the modification of CeO2 with Pr cations, 5% Ce0.2Pr0.8Oy sample, it decreased to 65% at 220°C due to an increase in the bond strength of oxygen in copper-containing centers. A maximum conversion of CO (93%) on a sample of 5% CuO/PrOy was detected at 200°C. Upon the modification of PrO2 with Ce cations, the activity of 5% CuO/Ce0.5Pr0.5Oy and 5% CuO/Ce0.2Pr0.8Oy catalysts did not exceed that of 5% CuO/PrOy. The forms of CO and CO2 adsorption on 5% CuO/Ce1 – xPrxOy samples were studied using the TPD method. In a range of 170–500°C, the desorption of oxygen from the supports of 5% CuO/Ce0.5Pr0.5Oy and 5% CuO/PrOy samples was observed. The occurrence of the reaction on 5% CuO/Ce1 – xPrxOy catalysts was discussed. With consideration for the properties of CO complexes formed on copper-containing oxidation and adsorption centers, their participation in the reaction of low-temperature oxidation in hydrogen was examined.

The (5–15)%CoO/ZrO2(T + M) catalysts were studied by XRD and TPR-H2. In the oxidized samples, 80–90% of cobalt oxide is present in the form of finely dispersed Co3O4, which interacts with the support ( $${\text{Co}}_{x}^{{3 + }}{\text{Co}}_{y}^{{2 + }}{\text{O}}_{z}^{{2 - }}$$ clusters), and the rest of it (10–20%) are the Co3O4 phase and dispersed CoO. In the CO oxidation to CO2, the most active samples were CoO/ZrO2(T + M) containing 10 and 15% cobalt at T50 = 120°C. Nearly 100% conversion of CO to CO2 was observed on 10%CoO/ZrO2(T + M) at 160–200°C. The conversion decreases at 220–260°C as a result of competition for oxygen in the oxidations of CO and H2, and at 280–360°C, as a result of increased consumption of CO in the methanation reaction. The CO oxidation in the range 50–200°C occurs on the clusters localized on the ZrO2(T) particles. The Co3O4 phase in pure oxide and in the 5%CoO/(SiO2, ZrO2(M)) catalysts has low activity under these conditions. The temperature dependence of CO conversion was discussed based on the data on the properties of adsorption complexes formed with participation of oxygen clusters and the gas phase.

The regularities of the formation of the phase composition of crystalline silica during the processing of amorphous precursors in the aqueous fluid media below and above the critical point of water aimed at the formation of optimal support for the methane oxidative coupling (OCM) catalyst were studied. It was shown that the phase composition of SiO2 and the rate of phase formation strongly depend on the processing conditions (temperature, time, phase state of the water fluid) and the presence of trace amounts of impurities in the initial amorphous material. Nevertheless, for different precursors, the phase formation occurs, apparently, via the formation of the same bulk-hydrated structures. Optimization of the processing in the water fluid and subsequent heat treatment made it possible to obtain an OCM catalyst that is significantly more efficient than the one obtained by the conventional procedure using an amorphous support. It was concluded that the catalytic properties are entirely determined by chemical and phase transformations occurring in the active component (Na2WO4–Mn2O3) on the support surface and do not depend on the doping of the support with the ions composing the active phase.

The effect of the density of water fluid in the range of ~10–3–0.25 g cm–3 on the structuring of amorphous silica gel was studied at 380°C that exceeds the temperature of critical point of water. It was shown that a decrease in the specific surface area (Ssp) is observed already at the lowest density. As the latter increases, Ssp decreases further, and starting from the density of ~0.01 g cm–3, the formation of crystalline silica phases (cristobalite, keatit) was observed in the sample. Based on the observed regularities in the change in the morphology and crystallinity of SiO2, as well as on the data on the variations in the properties of the water fluid with temperature and pressure below and above the critical point, it was concluded that the increase in the structuring rate with an increase in the density of the water fluid is more likely due to the kinetic factor (mass action law) than with a change in the physical state of water (intermolecular interaction forces action). Using the obtained samples of treated silica gel as a support for the NaWMn/SiO2 catalysts it was shown that their efficiency in the oxidative coupling of methane decreases with increasing degree of crystallinity of the support. However, when supports that have undergone processing in the water fluid of relatively low densities (<0.05 g cm3) were used, the catalysts were more active and selective than the one prepared using the untreated silica gel.

Strontium and barium titanates deposited on a porous support (α-Al2O3) are synthesized by the treatment of previously deposited precursors (titanium oxide, strontium nitrate, or barium nitrite) in a water fluid medium at 400°C. The obtained samples are characterized by X-ray powder diffraction (XRD) analysis and scanning electron microscopy (SEM) with energy-dispersive X-ray (EDX) spectroscopy. It is found that, in the presence of titanium oxide, α-Al2O3 is partially hydrated to form basic aluminum hydroxide AlO(OH) (boehmite), which is not detected by XRD after the treatment of α-Al2O3 in a water fluid. SEM with EDX spectroscopy demonstrates that strontium ions under the conditions of the treatment in a water fluid preferably interact with titanium oxide to form SrTiO3, although the aluminum oxide content in the samples is much higher. The conditions are determined for obtaining systems with different spatial distributions of the supported component inside the granules of the support by varying the procedure of its preliminary impregnation with the titanium oxide precursor.

Исследованы закономерности формирования фазового состава кристаллического кремнезема при обработке аморфных предшественников в среде водных флюидов ниже и выше критической точки воды с целью получения носителя катализатора окислительной конденсации метана (ОКМ) оптимального состава. Для разных предшественников фазообразование протекает, по-видимому, через промежуточное образование одних и тех же аморфных объемно гидратированных структур; скорость этого процесса сильно зависит от условий обработки (температура, время, фазовое состояние водного флюида). Дальнейшее образование кристаллических фаз резко ускоряется примесями ионов щелочных металлов. Оптимизация процедуры обработки в водном флюиде и последующей термообработки позволила получить катализатор ОКМ, существенно превышающий по эффективности получаемый по стандартной процедуре на основе аморфного носителя. Сделан вывод о том, что каталитические свойства целиком определяются химическими и фазовыми превращениями, протекающими в активном компоненте (NaWO-MnO) на поверхности носителя, и не зависят от допирования носителя ионами, входящими в состав активного компонента. The regularities of the formation of the phase composition of crystalline silica during the processing of amorphous precursors in the aqueous fluid media below and above the critical point of water aimed at the formation of optimal support for the methane oxidative coupling (OCM) catalyst are studied. It is shown that the phase composition of SiO and the rate of phase formation strongly depend on the processing conditions (temperature, time, phase state of the aqueous fluid) and the presence of microimpurities in the initial amorphous material. Nevertheless, for different precursors, the phase formation occurs, apparently, through the formation of the same bulk-hydrated structures. Optimization of the processing in the aqueous fluid and subsequent heat treatment made it possible to obtain an OCM catalyst that is significantly more efficient than the one obtained by the conventional procedure using an amorphous support. It was concluded that the catalytic properties are entirely determined by chemical and phase transformations occurring in the active component (NaWO-MnO) on the surface of the support, and do not depend on the doping of the latter.

Исследовано влияние плотности водного флюида в диапазоне ~10- 0,25 г/см на структурирование аморфного силикагеля при 380 °С - температуре выше критической точки воды. Показано, что снижение величины удельной площади поверхности (5у) силикагеля наблюдается уже при наименьшей плотности; при ее возрастании происходит дальнейшее снижение 5у, а начиная с величины плотности ~ 0,01 г/см в образце наблюдается образование кристаллических фаз кремнезема (кристобалит, китит). На основании наблюдаемых закономерностей изменения морфологии и кристалличности SiO, а также анализа данных по изменению свойств водного флюида при варьировании температуры и давления ниже и выше критической точки сделан вывод о том, что возрастание скорости структурирования с ростом плотности водного флюида связано скорее с кинетическим фактором (закон действующих масс), чем с изменением физического состояния воды (действие сил межмолекулярного взаимодействия). Использование полученных образцов обработанного силикагеля в качестве носителя катализатора NaWMn/SiO для реакции окислительной конденсации метана показало, что эффективность катализатора снижается с ростом степени кристалличности носителя. Однако при использовании носителей, прошедших обработку при относительно низких плотностях водного флюида (< 0,05 г/см) катализатор более активен и селективен, чем при использовании исходного силикагеля. The effect of the density of water fluid in the range of ~10-0.25 g/cm on the structuring of amorphous silica gel was studied at 380 °C that exceeds the temperature of critical point of water. It is shown that a decrease in the specific surface area (S) is already observed at the lowest density; as the latter increases, S decreases further, and starting from a density of ~0.01 g/cm, the formation of crystalline silica phases (cristobalite, keatit) is observed in the sample. Based on the observed regularities in the change in the morphology and crystallinity of SiO, as well as the analysis of data on the variations in the properties of the water fluid with temperature and pressure below and above the critical point, it was concluded that the increase in the structuring rate with an increase in the density of the aqueous fluid is more likely due to the kinetic factor (mass action law) than with a change in the physical state of water (intermolecular interaction forces action). Using the obtained samples of treated silica gel as a support for the NaWMn/SiO catalyst for the oxidative coupling of methane it was shown that the efficiency of the catalyst decreases with increasing degree of crystallinity of the support. However, when using supports that have undergone processing at relatively low densities of water fluid (< 0.05 g/cm), the catalysts are more active and selective than the one supported on the initial silica gel.

It was shown, that Cu-doped hexagonal phases YGaO3, YInO3 and GdInO3 possess an intense broadband photoluminescence in the near infrared region. This photoluminescence is attributed to the unique crystalline lattice of studied hexagonal phases with trigonal-bipyramidal coordinated Ga3+ and In3+ ions. It was suggested that an emissive center in these phases is formed by heterovalent substitution of Ga3+ and In3+ for Cu2+. The energy level diagram of Cu2+ in trigonal-bipyramidal coordination offer some benefits for possible application of this impurity ion as an active center in broadband optical amplifiers and tunable lasers.

Синтез титанатов стронция и бария на пористом носителе (α-AlO) проводили обработкой предварительно нанесенных соединений-предшественников (оксида титана, нитрата стронция или нитрита бария) в среде водного флюида при 400 °С. Полученные образцы исследовали методами рентгенофазового анализа (РФА) и сканирующей электронной микроскопии, совмещенной с рентгеновским энергодисперсионным анализом (СЭМ-ЭДА). Установлено, что в присутствии оксида титана происходит частичная гидратация α-AlO с образованием основного гидроксида AlO(OH) (бёмит), который не обнаруживается методом РФА при обработке в водном флюиде чистого α-AlO. Методом СЭМ-ЭДА показано, что, несмотря на значительно более высокое содержание в образцах оксида алюминия, в условиях обработки в водном флюиде ионы стронция преимущественно взаимодействуют с оксидом титана с образованием SrTiO. Определены условия получения систем с различным пространственным распределением нанесенного компонента внутри гранул носителя путем варьирования метода предварительной его импрегнации предшественником оксида титана. The synthesis of strontium and barium titanates supported on the porous carrier (α-AlO) was performed via the treatment of the previously deposited precursors (titanium oxide, strontium nitrate, barium nitrite) in the water fluid medium at 400 °C. The obtained samples were characterized using the X-Ray Powder Diffraction (XRD) and Scanning Electron Microscopy combined with Energy Dispersion X-Ray analysis (SEM-EDX) techniques. It was found that in the presence of titanium oxide α-alumina undergoes a partial hydration with the formation of the basic aluminum hydroxide AlO(OH) (boemite) that was not found using the XRD method after the treatment of the pure α-AlO in the same conditions. Using the SEM-EDX method we demonstrated that in spite of much higher content of alumina in the samples, strontium ions preferably interact with titania forming SrTiO. It was shown that samples with different spatial distribution of the supported component inside the carrier particle can be obtained by varying the method of the preliminary deposition of the titania precursor (titanium tetra-iso-propoxide).