Structure and properties of vacuum arc single-layer and multiperiod two-layer nitride coatings based on Ti(Al): Si layers

The paper provides an analysis of impact of deposition conditions on structural and phase state and thermal stability of vacuum arc coatings based on Ti(Al):Si layer

Modeling of impact deformation processes of the ceramic container for radioactive waste storage

Results of researches in the field of designing containers for storage of radioactive materials are presented in the work. The purposes of researches include a development of an effective method of modeling static and dynamic deformation processes at shock impact on the ceramic container with radioactive materials at transportation. The next tasks have been solved: on the basis of the mathematical description of physic-mechanical processes of deformation of the complex design container has been chosen method of finite-element's for effective modeling of the stress-strain State of static and dynamic deformation processes in the containers made of ceramic elements; laws of deformation, estimations of durability and rigidity for designed containers have been received after calculations by means of the computer software; recommendations on perfection of a design of the container for maintenance of requirements to safety are given. Analysis Finite Element Method (FEM) has been conducted in the ANSYS system and results is presented

Quantum dynamics in canonical and micro-canonical ensembles. Part I. Anderson localization of electrons

The new numerical approach for consideration of quantum dynamics and calculations of the average values of quantum operators and time correlation functions in the Wigner representation of quantum statistical mechanics has been developed. The time correlation functions have been presented in the form of the integral of the Weyl's symbol of considered operators and the Fourier transform of the product of matrix elements of the dynamic propagators. For the last function the integral Wigner- Liouville's type equation has been derived. The numerical procedure for solving this equation combining both molecular dynamics and Monte Carlo methods has been developed. For electrons in disordered systems of scatterers the numerical results have been obtained for series of the average values of the quantum operators including position and momentum dispersions, average energy, energy distribution function as well as for the frequency dependencies of tensor of electron conductivity and permittivity according to quantum Kubo formula. Zero or very small value of static conductivity have been considered as the manifestation of Anderson localization of electrons in 1D case. Independent evidence of Anderson localization comes from the behaviour of the calculated time dependence of position dispersion.Comment: 8 pages, 10 figure

X-ray line formation in the spectrum of SS 433

The mechanisms for the formation of X-ray lines in the spectrum of SS 433 are investigated by taking into account the radiative transfer inside the jets. The results of Monte Carlo numerical simulations are presented. The effect of a decrease in line intensity due to scattering inside the jet turns out to be pronounced, but it does not exceed 60% in magnitude on the entire grid of parameters. The line broadening due to scattering, nutational motion, and the contribution of satellites can lead to overestimates of the jet opening angle $\Theta$ from the line widths in Chandra X-ray observations. The fine structure of the lines turns out to be very sensitive to the scattering effects. This makes its investigation by planned X-ray observatories equipped with high-resolution spectrometers (primarily Astro-H) a powerful tool for diagnosing the parameters of the jets in SS 433.Comment: 23 pages, 14 figures, to be published in Astronomy Letters, v. 38, n. 7, p. 443 (2012

Study of the ηπo\eta\pi^o system in the mass range up to 1200 MeV

The reaction $\pi^-p \to \eta\pi^o n$ has been studied with GAMS-2000 spectrometer in the secondary 38 GeV/c $\pi^-$-beam of the IHEP U-70 accelerator. Partial wave analysis of the reaction has been performed in the $\eta\pi^o$ mass range up to 1200 MeV. The $a_0(980)$-meson is seen as a sharp peak in S-wave. The $t$-dependence of $a_0(980)$ production cross section has been studied. Dominant production of the $a_0(980)$ at a small transfer momentum $t$ confirms the hypothesis of Achasov and Shestakov about significant contribution of the $\rho_2$ exchange ($I^GJ^{PC}=1^+2^{--}$) in the mechanism of $a_0(980)$ meson production in $t$-channel of the reaction.Comment: 4 pages, 3 figures, talk given at HADRON'9

Formation of superhard state of the TiZrHfNbTaYN vacuum-arc high entropy coating

Complex studies of the formation of the superhard state in the TiZrHfNbTaYN vacuum arc high entropy coating were carried out. Based on the approach of the structural surface engineering, the regularities of the formation of the triads composition-structure-physic mechanical properties depending on the supplied potential displacement are establishe

Influence of the magnitude of the bias potential and thickness of the layers on the structure, substructure, stress-deformed state and mechanical characteristics of vacuum-arc multi-layered (TiMo)N/(TiSi)N coatings

Layers based on titanium nitride doped with molybdenum and silicon were used to create a multilayer composite. In this case, the mismatch between the lattice periods of (TiMo)N and (TiSi)N layers was about 1%. It was found that in the (TiMo)N/(TiSi)N multilayer composite, such a mismatch of the periods in the constituent layers does not change the single-phase state of the composite even at relatively large layer thicknesses (about 350 nm). The creation of a (TiMo)N/(TiSi)N composite with a nanometer layer thickness allows one to reduce the magnitude of macrostresses (a large value of which is characteristic of single-layer (TiMo)N coatings) and change the substructural characteristics in a wide range of values. It has been established that the use of multi-element (TiMo)N and (TiSi)N layers in a multilayer coating design allows one to achieve a high-hard state with high adhesive strength and good tribological characteristic

Structure and mechanical properties of TiAlSiY vacuum-arc coatings deposited in nitrogen atmosphere

The effect of a negative bias potential applied to the substrate on elemental composition, structure, and mechanical properties of vacuum-arc TiAlSiY nitride coatings is investigated by different method

Structural features and physico-mechanical properties of AlN-TiB2-TiSi2 amorphous-like coatings

The coating of the AlN–TiB2–TiSi2 system has been produced by the magnetron sputtering of a target. At the hightemperature (900 and 1300°C) actions the coating crystallization to form crystallites of sizes 11–25 nm has been observed. It has been defined that the amorphouslike structure is promising for the use of these coatings as diffusion barriers both as the independent elements and a contacting layer in multilayer wearresistant coatings. It has been shown that the use of the resultant composite as an effec tive protective coating for cutting tools will make it possible to increase the tools wear resistance by more than 30% at the temperature up to 1300°C in the cutting zone

Open multistate Majorana model

The multistate Majorana model in the presence of dissipation and dephasing is considered. It is proven that increasing the Hilbert space dimension the system becomes more and more fragile to quantum noise. The impossibility to recast the problem in the form of a set of independent spin-$1/2$ problems because of the presence of the noise is pointed out