Structure and catalytic activity of the novel heterostructured FePt/h-BN nanomaterials in carbon monoxide oxidation reaction were studied. Transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction methods were used for structure and surface chemical composition investigation. Developed materials were demonstrated to have enhanced catalytic activity with 100% CO conversion at 250 °C. Structure ordering in FePt nanoparticles was observed during thermal activation of the material.

The structure of new heterogeneous FePt/ h -BN nanomaterials and their catalytic activity in the model reaction of carbon monoxide oxidation have been studied. The structure and surface composition were analyzed by methods of transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. It is established that the new materials exhibit pronounced catalytic activity and can provide complete CO conversion at a temperature of 250°C. The process of thermal activation involves ordering of the structure of FePt nanoparticles.

In this work, the photocatalytic activity and sorption capacity of heterogeneous structures AgCl/h-BN obtained by the polyol method were studied in comparison with the initial micron-sized h-BN powder. The chemical and phase composition, as well as the surface microstructure, were analyzed by scanning electron microscopy, energy dispersive spectroscopy, X-ray phase analysis, and X-ray photoelectron spectroscopy. High photocatalytic activity and sorption ability of heterogeneous structures AgCl/BN in the reaction of the organic dye methylene blue decomposition under ultraviolet irradiation were demonstrated.

The effect of ultrasonication time after hydrothermal synthesis of hydroxyapatite (HA) using the precursor system Ca(NO3)2–(NH4)2HPO4–NH4OH on the phase composition and degree of crystallinity was examined. HA samples were studied using x-ray diffraction and FT-IR spectroscopy. The studies showed that ultrasonication regardless of the duration had no effect on the phase composition and degree of crystallinity of the synthesized HA samples. HA phase Ca10(PO4)6(OH)2 with 0.97 degree of crystallinity was present in all studied samples.

The influence of the duration of ultrasonic treatment after hydrothermal synthesis of hydroxylapatite (HA) samples synthesized in the Ca(NO 3 ) 2 ‒(NH 4 ) 2 HPO 4 ‒NH 4 OH precursor system on the phase composition and crystallinity of the synthesized samples is considered. HA samples were investigated using X-ray diffraction and infrared Fourier spectroscopy. The study showed that ultrasonic treatment, regardless of the duration, does not affect the phase composition and crystallinity of the obtained HA samples. In all the studied samples, the presence of the HA phase Ca 10 (PO 4 ) 6 (OH) 2 with a crystallinity of 0,97 was established.

AbstractThe results of investigating the thermoelectric properties of the bulk р -type oxyselenides Bi_1 –_ x Pr_ x CuSeO ( x = 0, 0.04, 0.08) and Bi_0.96La_0.04CuSeO obtained by the solid-state reaction technique are presented. The temperature dependences of the thermopower, electrical resistivity, and thermal conductivity are measured at temperatures from room temperature to 800 K. Over the whole temperature range, a decrease in the electrical resistivity and thermopower is observed with increasing substitution level, while the thermal conductivity is almost unaffected by the substitution of rare-earth elements for bismuth. Despite the nominal valence of Bi, La, and Pr being the same, the replacement of bismuth by rare-earth ions leads to an increase in the charge-carrier concentration, which may be caused by a difference in the electronic configurations of ions, resulting in a shift of the Fermi level to the valence band.

In this work we present the results of the transport properties study for p-type Bi1-xLaxCuSeO (x = 0.02; 0.04; 0.06) oxyselenides. Accordingly to temperature dependencies of the electrical resistivity, charge carriers concentration and mobility, it was revealed that the substitution of Bi3+ ions to La3+ ions leads to charge carriers concentration enhancement caused by generation of holes, which is presumably attributed to the bismuth deficiencies formation with respect to the substitution level. The work was carried out with financial support from the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST “MISIS”.

The impact of fine metallurgical sludge on sunflower plants was studied. Found that metallurgical sludge are highly bioactive in relation to sunflower seeds. In making the habitat of plants aqueous solution sludge by more than 30% increase in germination energy of seeds. The most significant increase in the amount of sludge in the medium affects the length and weight of vegetative parts of sunflower. Thus, at concentration of 10% root length is increased about 5 times, and the length of the stem by 2.5 times compared to the control. The results can be used in the development of microelement fertilizers based metallurgical sludge, and during activities phytoremediation metallurgical waste.

The influence of initial components ratio on the phase formation features in Ni-Mo-N system is studied in this work. Analysis was performed by X-Ray diffraction, low-temperature nitrogen adsorption, thermogravimetry, Fourier transform infrared spectroscopy methods in this study. It was shown that the formation of the single phase specimen occurs when Ni:Mo ratio equals 2:3. The influence of metallic and intermetallic phases formation on specific surface area of the powder is revealed. The study of catalytic activity and stability of nitride catalyst in methanation reaction was performed. It was shown that they key product of the reaction is methane, which is confirmed by the IR transmission spectra. After 360 minutes of the reaction there are peaks of carbon monoxide, which is weighty confirmation of its presence in the product mixture. The reverse water-gas shift reaction may promote the increase of CO concentration.