In this work, the formation by thermal evaporation and condensation in vacuum and the structural evolution of palladium (Pd) and palladium oxide (PdO) films on NaCl, mica, and SiO2/Si(111) substrates were studied, together with phase transformations in epitaxial Pd films during oxidative annealing in air at 400, 550, and 700°C and reduction annealing in vacuum at 750°C. The regularities of the Pd → PdO → Pd structural and phase transformations were revealed. Oxidation of epitaxial Pd films produces PdO in two equivalent orientations: (001)[100]PdO ∥ (001)[110]Pd and (010)[101]PdO ∥ (100)[011]Pd. The solid-state reduction of Pd proceeds by an endotaxy mechanism and results in the (112)[11 1̅ ]Pd ∥ (100)[011]PdO orientation. Complete reduction of PdO produces a Pd film with a biaxial texture and a finer grain structure than the initial Pd film. A phase-composition gradient was found in the epitaxial PdO–Pd heterostructure. In this work, an approach using an epitaxial PdO film as an oxidizing substrate for the Li–Nb–O system was applied for the first time. This approach made it possible to achieve LiNbO3 stoichiometry during vacuum annealing and to synthesize a LiNbO3/Pd heterostructure from the initial Li–Nb–O/PdO heterostructure. The results provide prospects for developing new materials and technologies in fields such as microelectronics and nanotechnology, sensing, and catalysis.
Modern radiation physics of condensed matter is largely concerned with so-called complex systems, for which the conceptual and mathematical framework of the “Complexity” ideology was developed; this ideology, in turn, is based on synergetics and synergistics. Both are based on accounting for strong nonequilibrium and nonlinearity. However, their objectives differ. Among the various types of nonlinearity, the search for mechanisms responsible for the emergence of nonadditivity from the combination of several causes is of particular importance. In this context, particular attention has been paid to biomedical problems, especially those related to radiation oncology, whereas the synergistics of nonadditivity has been studied to a much lesser extent for inanimate objects. In this work, particular attention was paid to modeling radiation processes in complex systems relevant to radiation science and radiation technology, in which different numbers of influencing factors are involved.
The effect of high-power ion beam (HPIB) of nanosecond duration on the corrosion of polycrystalline magnesium in physiological solution (0.9
The process of negative ionization of hydrogen on surfaces with a low work function plays an important role in the creation of highly efficient sources of negative ion beams used in accelerators, mass spectrometry, thermonuclear installations, and other high-tech areas. Increasing the efficiency of negative ion sources requires an in-depth understanding of the mechanisms of resonant charge transfer. In this study, the problem of electron exchange between an H0 atomic particle and a cesium-coated W(110) surface was considered and the negative ionization process was studied. The problem was described using the Anderson–Newnes theory, which allows one to take into account the dynamics of hybridization of the electron states of the adsorbate and the surface. Contrary to expectations based on the shifted Fermi sphere model, an increase in the parallel component of the particle velocity led to a decrease in the probability of H– formation. This discrepancy with the predictions of traditional models emphasizes the need to take into account the dynamic aspects of electron exchange and the initial conditions of the system.
The transformation Jacobian for the distribution function of sputtered atoms crossing a spherical potential barrier with refraction is analyzed analytically in the approximation of small polar angles close to the surface normal. For such a potential barrier, a molecular dynamics model is used to analyze the effect of its curvature γ on the angular distribution of sputtered atoms from an Au(001) single crystal. The model accounts for repulsion from the nearest surface atoms and then applies the exact formula for refraction at the potential barrier. As the curvature of the potential barrier decreases, the direction toward the Wehner spot shifts away from the surface normal. The experimental data correspond to an almost planar potential barrier with γ ≤ 0.2.
