Origin of the giant dipole resonance width of atomic nuclei
Origin of the giant dipole resonance width of atomic nuclei
I. M. Kapitonov
Based on the analysis of the entire set of available experimental and theoretical studies of the Giant Dipole Resonance of atomic nuclei, the main factors of the formation of its width and structure were established
Show AbstractStructure, phase composition and functional characteristics of titanium-based coatings obtained via reactive magnetron sputtering
Structure, phase composition and functional characteristics of titanium-based coatings obtained via reactive magnetron sputtering
V. M. Avdyukhina$^1$, M. M. Khrushchov$^2$, I. S. Levin$^2$, E. V. Kashurkin$^1$
The results of a comprehensive study of the effect of phase composition and microstructure features on the mechanical and tribological properties of titanium coatings obtained by reactive magnetron sputtering in the atmosphere of acetylene and nitrogen are presented. It was established that all the coatings contain amorphous carbon, and different types of stoichiometric and non-stoichiometric carbide, nitride and oxide phases of titanium. The resulting coatings have a low coefficient of friction and remain operational at contact pressures up to 450 MPa during 6000 cycles of friction-fatigue tests.
Show AbstractOptical communication systems on helical beams
Optical communication systems on helical beams
P. V. Korolenko$^{1,2}$, A. V. Averchenko$^1$, A. M. Zotov$^1$, N. N. Pavlov$^{1,2}$, Yu. V. Ryzhikova$^1$
The features of light beams propagation with a helical wavefront structure in information laser systems are analyzed. Calculations using parallel computing technology on the CUDA platform that significantly speeds up the calculation process is performed. The requirements for the alignment of the optical system with the multiplexing of beams in open propagation channels are formulated. It is shown that when radiation propagates in a medium with random inhomogeneities, the standard deviations of a Gaussian beam are one and a half times larger than the deviations of a beam with a helical wave-front shape. This indicates a high degree of stability of helical beams at atmospheric turbulent lines. A new method of generating high-power helical beams using the radiation of multi-pass modes of laser resonators is proposed.
Show AbstractA new approach to the study of optical illusions in school
A new approach to the study of optical illusions in school
S. B. Ryzhikov$^1$, Yu. V. Ryzhikova$^2$
The current FGES pays great attention to interdisciplinary training. The authors consider the most effective approach when selecting an interesting problem for students, which is seen from the perspective of different disciplines. The article illustrates the application of this approach on the example of considering the problem of human vision. The study of the phenomenon of vision requires the integration of knowledge of mathematicians, physicists, physiologists, psychologists and other specialists. The purpose of training is to be no transfer of a large number of illusions, and to identify the causes of their appearance. It is necessary to convey to students the idea that our vision has unique capabilities, and illusions are side effects of the manifestation of these abilities.
Show AbstractCalculation of α-decay characteristics of superheavy nuclei based on mass relations
Calculation of α-decay characteristics of superheavy nuclei based on mass relations
E. V. Vladimirova$^1$, B. S. Ishkhanov$^{1,2}$, M. V. Simonov$^1$, T. Yu. Tretyakova$^2$
In order to study the stability of the method of local mass ratios in the field of superheavy elements, based on the formula for estimating the residual np-interaction, the binding energies of the nuclei A > 200 are calculated. Comparison with experimental data AME2016 shows high accuracy and stability of the method. The characteristics of α-decay are predicted for Z = 102 − 106 and N = 144 − 157 isotopes.
Show AbstractCharacteristics of pp collision events from ATLAS OpenData
Characteristics of pp collision events from ATLAS OpenData
I. O. Volkov, I. S. Diachkov, L. N. Smirnova, R. A. Shorkin
Parameter distributions for events with W, Z boson and top quark pairs production in ATLAS open data are presented. Comparison of distributions in different ranges of parameters was carried out. Obtained results were compared with public results of ATLAS collaboration.
Show AbstractAnalysis of the crack resistance of adhesive joints using the finite element method and the cohesive zone model
Analysis of the crack resistance of adhesive joints using the finite element method and the cohesive zone model
A. A. Ustinov, P. G. Babaevskiy, N. A. Kozlov, N. V. Salienko
The method of cohesive zones allows us to evaluate the stability of the material, both to the beginning of the growth of an existing crack, and to the occurrence and development of defects in places of stress concentration. The ability to reliably determine the destruction parameters of adhesive joints (AJ) and predict the behavior of structural elements with their use under loading is an important task for the aircraft industry. It is proposed to use in the finite-element 3D model of stratification according to mode I of the AJ sample in the form of a two-console beam, the length of the cohesive zone (lcz) calculated from the experimentally determined parameters — the local interlayer cohesive strength of the material (σIC) and the intensity of release of elastic energy (GIC). The calculated length of the cohesive zone is applied in the model to calculate the minimum number of finite elements at their optimal size, which ensures higher accuracy of calculations of the main parameters of crack resistance of samples of laminated carbon fiber while minimizing the amount of calculations. The objects of study were AJ sheets of aluminum alloy D-16, which were glued together with dispersion-filled adhesives of industrial grades EPK-1, VK-9, and K-300-61, which are widely used as structural adhesives in the production of aerospace structures. As a result of the research, the main parameters of crack resistance were determined and the optimal length of the final cohesive element was selected, and the resulting model accurately describes the process of crack growth. The results obtained correlate well with the results of experiments.
Show AbstractRapid assessment method of temperature-time and deformation-force parameters of a thermally stimulated shape memory effect in polymer composites by dynamic mechanical analysis
Rapid assessment method of temperature-time and deformation-force parameters of a thermally stimulated shape memory effect in polymer composites by dynamic mechanical analysis
A. A. Slyusarev, P. G. Babaevskiy, G. M. Reznichenko, I. G. Agapov
Thermally stimulated shape memory effect (TS SME) in polymer composite materials (PCM) and cross linked polymer matrices is the ability of these materials when heated to a certain temperature, the so-called conversion temperature (Tc), easy to change the shape when an external force is applied, spontaneously restore in the absence of a restraining force and fix the modified and restored form upon cooling. The main factors determining the SME in PCM are: • a large value and reversibility of highly elastic deformations of the matrix at Tc> Tg = Th; • elastic deformations of the reinforcing components (fabric, tape); • freezing of highly elastic deformation at T << Tc. A technique has been developed for the rapid assessment of temperature-time and deformation-force parameters of the TS SME using a dynamic mechanical analyzer (DMA). The technique was tested on carbon plastic with a different type of matrix and fabric as reinforcing. In the developed method for the accelerated evaluation of the deformation-force parameters of the TC SME in PCM at the stages of changing, restoring and fixing their shape, the sample sizes are too small. Therefore, the results obtained can be used only with an accelerated selection of the composition of materials and a comparative assessment of the conditions and effectiveness of the manifestation of the TS SME in them.
Show AbstractThermal modification of cartilage and speckle-modulated images monitoring
Thermal modification of cartilage and speckle-modulated images monitoring
M. L. Novikova$^{1,2}$, A. V. Yuzhakov$^2$, O. I. Baum$^2$
Today non-destructive laser effect on tissue is used in many areas of medicine. By creating a laser-induced temperature field in the cartilage, one can achieve structural rearrangements, the formation of pores and even the shape changes due to the relaxation of mechanical stresses. In the process of laser exposure to cartilage, there is a change in the mechanical and optical properties of the tissue, which must be monitored to adjust the mode of exposure. This is conveniently done using the speckle interferometry method, the idea of which is to observe the interference pattern produced by the interaction of monochromatic coherent radiation with biological tissue. The paper presents the results of a study of the temporal and temperature dependences of the contrast function and cross-correlation. These dependencies can serve as a basis for monitoring laser exposure of tissue in real time.
Show AbstractNumerical modeling of thermal stress in solid-state solar pumped lasers
Numerical modeling of thermal stress in solid-state solar pumped lasers
M. D. Khomenko$^1$, S. D. Payziyev$^2$, K. M. Makhmudov$^2$
A software has been developed and verified for numerical modeling of temperature and thermal stress in crystals of a solar pumped solid-state laser resonator with an external sensitizer for a given volume absorption of radiation. A number of meshes were created for verification. It is shown that the developed solver can be used to calculate thermal stress in solar-pumped laser resonators, and its results for test cases are in good agreement with the analytical solution.
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