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Рассматриваются точные стационарные и
автомодельные решения уравнений Эйлера,
обладающие свойством частичной
инвариантности относительно некоторой
шестипараметрической группы Ли.
Приведены новые примеры вихревого
движения жидкости с закруткой в
криволинейных каналах. Проведена
классификация автомодельных решений
редуцированной системы с двумя
независимыми переменными, которая
допускает трехпараметрическую группу
растяжений, в то время как исходная
система уравнений Эйлера обладает
двухпараметрической группой.

Рассмотрено взаимодействие
сверхзвукового продольного вихря с
наклонной ударной волной. Построена
математическая модель продольного вихря.
Выявлено три режима взаимодействия:
слабый, умеренный и сильный. Численно
показано, что при сильном взаимодействии
возможно разрушение вихря. Исследовано
влияние определяющих параметров на тип
взаимодействия. Показано, что основное
влияние на тип взаимодействия оказывают
продольная скорость и угол клина,
формирующего ударную волну. Обнаружен
эффект расщепления основного вихря на
ударной волне при умеренном и сильном
режимах взаимодействия.

The modelling of self-oscillations and surface autowaves in CO oxidation reaction over Pd(110) has been carried out by means of the Monte-Carlo technique. The synchronous oscillations of the reaction rate and surface coverages are exhibited within the range of the suggested model parameters (under the conditions very close to the experimental observations). The dependencies of the simulation results on the lattice size and on the diffusion intensity have been studied. It has been established that the adsorbed CO diffusion anisotropy does not influence the oscillation kinetics but leads to the appearance of the propagating reaction fronts on the palladium surface elliptically stretched along the [110] direction in close agreement with the known experimental data.

The influence of the structure and composition of precursor (which is used as support after treatment) and the structure of copper particles formed in the course of activation of copper containing catalysts by hydrogen on their catalytic properties in methanol dehydrogenation and reactivity towards hydrogen adsorption has been studied. The reactivity of catalyst towards hydrogen adsorption was investigated by means of Thermal Desorption Spectroscopy (TDS). Two catalysts preserving the structure of their precursor-oxide after reduction (CuZnSi and CuCr) and having strong bonds of metal particles with the surface are characterized by hydrogen adsorption at elevated temperatures. This type of adsorption is not observed for usual unsupported metal copper and for two other catalysts Cu/SiO₂ and Cu/Cr₂O₃. Methanol dehydrogenation proceeds via successive reactions 2CH₃OH = CH₃OOCH + 2H₂ (I) and CH₃OOCH = 2CO + 2H₂ (II). The catalyst activity in reaction (II) greatly depends on the state of metal copper in the catalyst. It was assumed that catalyst activity in methyl-formate conversion to CO and H₂ and, hence, the selectivity of methanol dehydrogenation in respect to methylformate at moderate methanol conversion depends on the character of interaction between metal copper particles and catalyst oxide surface, which is determined by the composition and structure of oxide precursor.

Combined XPS and ex situ STM study of the specially prepared model supported silver catalysts was performed. The drastic difference in the Ag particle shape, size distribution and spreading over the support surface were observed for alumina support as compared with pyrographite one. This effect emphasizes the important influence of the substrate nature on the morphology and surface mobility of the supported metal particles

Procedures for synthesis of thermally stable up to 750 °C zirconiα-pillared clays (ZrPC) via intercalation of a montmorillonite clay with zirconium polyoxocations modified by cations of Ce, Fe, Al, Ca, Sr, Ba, were elaborated. Optimization of the preparation procedure allowed to obtain samples with specific surface area up to 300–400 m²/g, the gallery height up to 10 Å and micropore volume up to 0.13 m²/g. Active components comprised of copper cations and/or Pt clusters were supported on ZrPC by using photoassisted deposition. The structural and surface properties of pillars and effects of mutual interaction between the nanosized zirconia particles, and metal and oxide components were elucidated by using EXAFS, UV-Vis, ESR, H₂ TPR, NO_x TPD and FTIRS of adsorbed CO molecules. Catalytic properties of these systems were characterized in the reactions of NO_x selective reduction in the excess of oxygen by propane, propylene and decane. Strong interaction between the Pt atoms and copper cations resulted in substantial variation of the reactivity of the surface oxygen as well as bonding strength and coverages of surface ad-NO_x species. It was reflected in substantial improvement of the low-temperature activity of these systems as compared with those containing separate components. The nature of cation used for pillar modification was found to affect catalytic properties of supported active components, which can be explained by variation of the pillars structure and uniformity of their spatial distribution in clay galleries.

The reasonable scheme of commercially valuable odour chemicals syntheses starting from renewable natural material α-pinene includes the explored reaction of verbenol hydrogenation into verbanol under mild conditions over Pd/C catalyst. The possibility of verbanol stereoisomers preparation with controlled isomer distribution that defines a practical use of scheme as a whole is considered. The effects of the hydrogen pressure, temperature and catalyst content on the isomers re-proportioning in the course of verbenol hydrogenation are studied. The main factors permitting the hydrogenation process to direct to the definite verbanol isomers production were found to be hydrogen pressure and reaction temperature. Isoverbanol/neoiso verbanol ratio increases with hydrogen pressure growth from 2 to 11 bar and temperature decrease from 50 to 90 °C.

A novel scheme for the organization of the three-phase process has been proposed, basing on a new type of a stochastically organized porous and catalytically active composite monolith (PCM). The high catalyst loading (1 g/cm³) and high heat conductivity (3 W/(m K)) make this new material very attractive for exothermic multiphase processes, e. g. for the Fischer–Tropsch synthesis. The possibility of preparing strong PCMs with the permeability of 10–500 mDarcy has been demonstrated. The gas-vapor phase flow through a PCM particle can be performed via transport pores which diameter was measured as 4–10 mm. The pressure drop has been shown to be reasonable for the Fischer–Tropsch synthesis. The effectiveness of the PCM usage at 0.1MPa, 210 °C has been found to be above 70 %. PCM material was concluded to be the prospective

Selective oxidation of CO in excess hydrogen and in the presence of CO₂ and H₂O has been studied over monometallic Pt, Ru and bimetallic Pt–Ru supported on porous carbonaceous material catalysts. The catalysts provided CO conversion ³98 % and seem to be promising for efficient single-step removal of CO from hydrogen-rich streams containing CO₂ and H₂O.

The composition of modified monolith zeolite catalysts containing the basic components in the washcoating layer is suggested. When the washcoating layer contains 80 % zeolite, 10 % TiO₂, and 10 % Al₂O₃, the catalyst exhibits both activity and adhesion strength. The titanium catalyst is stable to sulfur poisoning (H₂S) at 500 °C; a small decrease in the catalyst activity at 400 °C is no longer observed after regeneration. Introducing 4 % mass Ce (calculated for respect to the washcoating) into the ready catalyst, one can preserve the catalyst activity and provide its stabile operation in the presence of water vapour both at 400 and 500 °C. Activity of the titanium-cerium-modified monolith catalyst is stable in the presence of water vapour and sulphur compounds in the gas mixture at a time.