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The kinetic characteristics and temperature quenching of the luminescence of optical centers of silicon vacancies (SiVs) in diamond films grown in microwave plasma on substrates of aluminum nitride and synthetic diamond are investigated via laser excitation at a wavelength of 640 nm.

The commented article contains numerous errors. The presentation of experimental data is slipshod and biased. They are not credible. The author had no reason to write about the scientific achievements outlined in the sections Abstract and Conclusion. One of the main conclusions of the work, that the author for the first time experimentally observed relation between orbital angular momentum of femtosecond laser radiation and induced by this radiation helicity of the tracks in crystals, has not been confirmed by direct check experiments. No orbital angular momentum of the exciting radiation nor the twisted tracks has been observed in the experiments. Other conclusions are also baseless.

The axial VUV radiation intensity distribution (< 130 nm) of an air glow discharge at pressure 50–530 Pa was obtained by the thermoluminescent method using the CaSO4·Mn thermoluminophor. The regions of maximum intensity of VUV radiation are the near-electrode regions in a wide range of pressures and voltages. The positive column of a glow discharge is also an area of intense VUV radiation at high-voltage. The formation of thin layer of luminescent defects on the faces of planar lithium fluoride crystals located in the positive column and Faraday dark space of a glow gas discharge was studied. By using a MicroTime 200 time resolution laser confocal scanning luminescence microscope (PicoQuant Gmbh) it was shown that the highest concentration of luminescent defects corresponds to the sides of the crystals that were irradiated near the electrodes.

Luminescence kinetics in the temperature range of 80–480 K and the red region of the spectrum is studied for Brazilian diamonds. Components with decay time constants of 23 and 83 ns are observed at room temperature after being excited by laser radiation with wavelengths of 375 and 532 nm, which differs considerably from the data published earlier for the luminescence kinetics of NV0- and NV–-centers.

Results of investigation of peculiar properties related to the structure of plant cell vacuolar membranes are discussed. This investigation was conducted with the aid of confocal microscopy, which allowed us, in the process of scanning, to reveal nanotubes and vesicules in the preparations of isolated vacuoles. Such membrane nanotubes were observed both inside and outside the vacuoles, and, in the case of scanning intermittently at equal time intervals, transition of vesicules with a membrane nanotube. Furthermore, scanning of isolated vacuoles was conducted at various distances from the glass basement. Each time, in the upper part of an isolated vacuole lying on the basement, we observed a large segment of vacuolar membrane and registered the effect of highly intense fluorescing of some of the membrane segments. Distributions of laurdan fluorescence generalized polarization (GP) values for the vacuolar membrane on the whole and for the intensely fluorescing membrane segments have been obtained. It was discovered that the microviscosity of intensely fluorescing membrane segments essentially differs from the microviscosity of the rest part of the membrane.

Line-by-line two-dimensional step small-scale scanning irradiation of a transparent cubic LiF crystal was carried out by intense linearly polarized femtosecond laser radiation in the multiple filamentation mode. As a result, isolated longitudinal extended tracks consisting of induced color centers were formed in the medium. It was found that no transverse periodicity associated with the scanning step is observed in the arrangement of tracks formed by laser filaments. This is because inhomogeneities that stimulate filamentation are not contained in the laser beam itself but are formed randomly when the medium interacts with the first laser pulses and are supported and amplified by subsequent pulses. The efficiency of color center formation in crystals at normal laser beam incidence on the cube face depends periodically on the azimuth angle θ between the electric vector and the cube edge on the face, with the period of π/2. It was found that azimuthal dependences for defect formation (maximum at θ = π/4) and for carrier photogeneration (maximum at θ = 0) are in the antiphase. Calculations showed that the processes of self-focusing and filamentation controlled by the components of the third-order nonlinear susceptibility tensor are most effective at the orientation where θ = π/4. The experiment showed that at such an orientation, the critical power and the length of self-focusing decrease, and therefore, the density of the number of filaments in the beam section increases and, as a result, the average concentration of the color centers created by laser filaments increases.

The spectral properties of a promising laser material, ternary molybdate Li3Ba2Gd3(MoO4)8:Nd3+, are studied (i.e., its optical absorption spectra, luminescence spectra, kinetic of luminescence decay, and temperature dependence of luminescence). Luminescence of the crystalline matrix is detected, and the temperature dependence of its intensity and reabsorption by neodymium are investigated.

The experiments conducted on tonoplast of Beta vulgaris L. roots were performed to identify detergent-resistant lipid-protein microdomains (DRMs, interpreted as lipid rafts).The presence of DRMs can be found when dynamic clustering of sphingolipids, sterols, saturated fatty acids is registered, and the insolubility of these microdomains in nonionic detergents at low temperatures is proven. The elucidation of tonoplast microdomains has been based on results obtained with the aid of high-speed centrifuging in the sucrose gradient. The experiments have shown that tonoplast microdomains are rich in sphingolipids, free sterols and saturated fatty acids (such a lipid content is also typical of lipid-protein microdomains of other membranes), while only few phospholipids are present in tonoplast microdomains. The presence of microdomains has been confirmed by fluorescence and confocal microscopy using filipin and Laurdan as fluorescent probes. The experiments with Laurdan have shown that tonoplast microdomains are characterized by a high order compared to characteristics of the rest of the tonoplast. Thus, the presence of detergent-resistant lipid-protein microdomains in the tonoplast has been demonstrated.