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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.

На модельной задаче исследовано влияние
термического возбуждения на динамику
вихревого возмущения конечной амплитуды
в сдвиговом потоке молекулярного газа.
Эволюция подобных вихревых структур
характерна как для нелинейной стадии
ламинарно-турбулентного перехода, так и
для развитой турбулентности. В
предположении относительно невысокого
уровня возбуждения в расчетах
использовались полные уравнения Навье —
Стокса сжимаемого теплопроводного газа,
в которых неравновесность учитывалась с
помощью коэффициента объемной вязкости.
Показано, что при увеличении объемной
вязкости (в диапазоне реальных значений)
скорость затухания энергии возмущений в
слабосжимаемом потоке возрастает
примерно на 10%. При увеличении числа
Маха эффект подавления возмущений
усиливается.

Изучается флаттер прямоугольной пластины
при произвольном направлении вектора
скорости относительно сторон пластины.
Построен численный алгоритм без
насыщения для решения задачи на
собственные значения. Приведены
результаты расчетов критической скорости
флаттера и соответствующие собственные
формы.

Some prospects of application of plasma spraying technique for the synthesis of supported catalysts are demonstrated. It was shown that Mn-containing catalysts deposited on γ-Al₂O₃ by means of plasma spraying demonstrate superior activity in methane oxidation reaction compared with those of reference catalysts prepared via standard conventional route. Gradient alumina layer sprayed on the surface of metal supports of different geometry improves the performance characteristics of combustion catalysts on metal supports during long term operation at high temperatures. A catalytic heat-exchanging (HEX) tubular reactor for combining exothermic combustion and endothermic methane steam reforming has been developed. The methane combustion and steam reforming catalysts were synthesized on the heat-conducting metal foam support materials by application of preliminary plasma spraying in order to increase adhesive properties of the active layer. The HEX reactor with perovskite or Pt supported catalyst on Ni–Cr foam material on the external surface of the HEX tube and with Ni containing reforming catalyst on the internal Ni foam was successfully tested in methane combustion reaction combined with methane steam reforming.

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.