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Впервые проведено моделирование возникновения нелинейных уединенных волн в системе, описываемой многочастичными потенциалами межатомного взаимодействия. Исследовано поведение свободной поверхности кристаллитов Ni и Аl в условиях высокоскоростного нагружения. Результаты расчетов показали, что уединенные импульсы, инициированные высокоскоростным нагружением, увеличивают свою амплитуду примерно в 1,5 раза в области свободной поверхности Ni и практически не изменяются в области свободной поверхности Аl. Природа данного эффекта связывается с различиями остов - остовного взаимодействия Ni и Аl.

С позиций механизма гидродинамической неустойчивости построена аналитическая теория процесса волнообразования на контактной границе при сварке взрывом. В качестве определяющих факторов принимается существенное действие вязких и инерционных сил, развивающихся при интенсивном соударении в области текучего состояния образцов. Полученные результаты согласуются с экспериментальными данными и объясняют наблюдаемые эффекты. Отдельно рассмотрен специфический случай уменьшенного сварочного зазора.

Исследованы особенности взрывного плакирования пластин и оболочек из стали Ст. З фольгами из меди и алюминия толщиной 20 и 50 мкм. Показано, что надежное плакирование наблюдается, если толщина фольг соизмерима с высотой микрорельефа плакируемой поверхности. При улучшении чистоты обработки поверхности качество соединения ухудшается. Улучшению качества соединения способствует увеличение длительности нагружения. В процессе плакирования уменьшается микрошероховатость обрабатываемой поверхности.

Приведены результаты экспериментальной оценки скорости разложения пероксида водорода в эмульсии с отвержденной дисперсионной средой.

Structured catalytic reactors have a large potential in Process Intensification. In many respects they outperform conventional reactors such as packed-bed and slurry reactors, both for gas and for gas – liquid systems. The most important structured reactors are based on gauzes, foams, and monoliths. In general, monoliths are the most satisfactory structured reactors. In gas-phase applications they are often preferred due to their favourable properties with respect to selectivity, pressure drop, and robustness. Their millisecond characteristics have potential in syngas production and selective conversions into valuable products. In gas-liquid applications they exhibit high rates, high selectivity (for serial kinetics), and they operate close to pluγ-flow behaviour. They are compact reactors with excellent performance in activity and selectivity. They allow co- as well as counter-current operation at common industrial conditions and can be used in multifunctional reactors, e. g. catalytic distillation. The use of a structured reactor allows the decoupling of intrinsic reaction kinetics, transport phenomena, and hydrodynamics. In this way these processes in a catalytic reactor can be optimised independently, giving rise to an excellent reactor performance. Structured catalysts and reactors will play a major role in Process Intensification.

In the present study the use of planar silicon-based models for hydro-treating catalysts is discussed. The specific flat nature makes these models amenable to high resolution surface-sensitive techniques such as XPS. The additional possibility to measure the activity of such model catalysts in thiophene hydrodesulfurization provides a powerful tool to determine structure-activity relations. Here, we study the effect of chelating agents (NTA and EDTA) on the sulfidation order of NiMo catalysts. The XPS results clearly show that the use of these chelating agents retards the sulfidation of Ni with respect to Mo. Especially, EDTA is effective by postponing Ni sulfidation after Mo is completely sulfided. The latter catalyst also displays the highest activity which is attributed to the highest amount of `Ni-Mo-S'-type phases. In essence, the results underpin the notion that such `Ni-Mo-S' phase can be formed effectively when Ni sulfidation proceeds after MoS₂ has been formed. When Ni sulfides at too low temperature, inactive bulky Ni₃S₂ clusters are formed.

Heat transfer experiments with and without chemical reaction were performed in a wall-cooled tubular reactor. The oxidation of carbon monoxide over a CuO/γ-alumina catalyst was used as a model reaction. A two-dimensional heterogeneous reactor model was used for calculation of the temperature and concentration profiles inside the packing. The experiments were performed at Re between 200 and 1400, reactor pressures of 3, 5.9 and 8 bar, wall temperatures of 156, 180 and 200 °C and CO inlet concentrations ranging from 0.1 to 1.5% vol. The obtained data show that a radial distribution of the axial fluid velocity should be taken into account to reconcile the effective heat transport parameters obtained from experiments with and without reaction.

The electronic peculiarities of the Pt(100)–(1 x 1) surface effected by various adsorbates and interactions in adsorbed layer were studied by the Disappearance Potential Spectroscopy (DAPS). Two types of features were observed in DAPS spectra. The first type corresponds to an ordinary threshold excitation of platinum core electron to an available vacant state. These features are attributed to the substrate properties, and their positions are in good agreement with corresponding Local Density of States (LDOS) calculations. The second type of features new way of primary electron energy consumption – the conjugate electron excitation, which includes the above threshold transition of the substrate core electron, accompanied by excitation of the valence electron of adsorbed species to vacuum level. Positions of the respective spectral satellites are close to corresponding ionization potentials of a given species in adsorbed layer. Our experimental data show altogether more than 10 satellites, providing the evidence of reliability of the conjugate electron excitation process. The present results as a whole experimentally demonstrate the substantial unity of the substrate and adsorbate electronic structures.

Some new results concerning complex dynamics in a kinetic model of heterogeneous hydrogen oxidation over metallic catalysts are presented. Relaxation oscillations with a high sensitive dependence on the initial conditions arise in the three-variable system with fast, intermediate and slow variables due to existence of the canard cycles that occur in the one-parameter family of two-variable subsystems. A key feature of the weakly stable dynamics appearance will be successive period doubling bifurcations in which the system behaviour becomes progressively more complex until the attractor appears.

Monolith sorbents/catalysts that have potential in simultaneous removal of H₂S and NH₃ from hot fuel gas were developed. Preparation methodology and composition of supported honeycomb sorbents/catalysts, based on manganese oxides modified by Fe and Cu oxides, have been optimized. Impregnated and washcoated monolith catalysts were tested in ammonia high temperature decomposition and H₂S sorption. Approaches for improving the thermal stability and catalytic activity under reaction conditions are described.