Bulletin of the Russian Academy of Sciences: Physics最新文献

It has been experimentally established that a mesogenic europium(III) β-diketonate complex fixed on a quartz substrate by drying a highly concentrated solution of the complex in carbon tetrachloride can reduce the luminescence brightness of Eu³⁺ ions during prolonged UV laser irradiation and spontaneously restore the initial luminescence parameters when kept in the dark for at least 22 h at room temperature.

In this paper, we studied the effect of near-ultraviolet laser radiation on the survival of bovine embryonic lung culture cells in the presence of antioxidants, namely vitamins E and C. We showed how cell viability changed at different wavelengths. We assessed how increasing the laser radiation power affected cell survival. In the presence of vitamins C (ascorbic acid) and E (tocopherol), a smaller decrease in cell survival was observed, indicating a relative balance between active oxygen species and antioxidants.

The derived master kinetic equation is used to determine the features of the nature of an isolated object, an absorber, on which the state of a broadband single-photon excitation is transferred. In the role of the absorber, a quantum oscillator or a two-level atom is considered. It is shown that, in the case of a nonresonant interaction between the packet and an intermediary, and between the intermediary and the absorber, the transfer of the state of a single-photon packet is possible if the absorber is a quantum oscillator. In the case where the transfer is to a two-level atom, the excitation transfer is only partial.

Glass–water and glass–air interfaces were visualized by second-harmonic generation microscopy. It was shown that the electrostatic surface potential can be determined from the recorded intensity of the signal from the glass surface in contact with solutions with different pH. Comparison of images of glass in contact with air and an aqueous solution at pH 2 hinted towards the similarity in the molecular structure of these interfaces.

A quantum memory scheme consisting of three optical resonators that form a photonic molecule with a programmable spectrum topology is studied. The dependence of the spectrum on the tuning parameters is analyzed to perform effective signal transfer to memory. The dynamics of the field in individual resonators is calculated for use in processing.

The effect of nozzle diameter on the mechanical properties of polymers reinforced with short fibers is critical for optimizing both print quality and structural performance in fiber-reinforced composites 3D‑printed using fused filament fabrication. This study investigated three types of polymer composites based on acrylonitrile butadiene styrene reinforced with carbon, glass, and basalt short fibers. The study involved experiments on monofilament samples before and after manufacturing process to evaluate and compare the effective tensile strength and stiffness properties of filaments reinforced with different materials.

The results of studying kinetics of strength decrease for two types (polyethylene and polyamide) of polymer fibers at X-ray irradiation. A structural-kinetic model of radiation induced changes in strength of fibers is considered, which accounts for the opposite effect of degradation and crosslinking of macromolecules on the oriented polymer (fiber) strength.

We present a version of the numerical analysis of the relationship between maximum strains on the ground surface and in an underground pipeline based on the results of solving the corresponding problem of the stress–strain state that arises as a result of the appearance of cavities of different geometries in the soil mass.

We proposed methods for developing predictive models of concrete gravity dam crest displacement. A deterministic finite element analysis (FEA) model is presented along with a method for identifying its mechanical properties. Performance of FEA model is compared to booster regression trees statistical model with hyperparameter tuning. Resulting models demonstrate excellent accuracy.

The study of multiphase systems based on magnetic fluids under external magnetic influence is a relevant direction in the development of contactless methods for controlling non-magnetic objects. This work aims to investigate non-magnetic inclusions in magnetic fluid. The results have been obtained through experimental methods and computer simulations using FEMM software.