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The formation and propagation of postfilamentation channels along a controllable path 150 m long are studied experimentally for collimated beams of different diameters. During multiple filamentation, a laser beam is compressed in global focus, after the passage of which its angular divergence is much greater than the divergence of postfilamentation channels generated during the filamentation. It is shown that postfilamentation channels have the intensity sufficient for the formation of multiple filamentation in optical elements after the end of the filamentation region at distances much longer than the filamentation length.

The vertical distribution of the organic component of aerosol in the boundary air layer and free atmosphere was studied on the basis of sampling from a board of Tu-134 “Optic” airborne-laboratory. The altitude range was divided into two layers: 0.5-2.0 and 3.0-7.0 km. It is shown that the aerosol organic component concentration exponentially decreases with altitude. The drop of the concentration makes 7.5 times from the surface air layer to the free troposphere. The maximal concentration in the surface air layer is observed for n-C₁₉H₄₀; in the boundary layer and free atmosphere, for n-C₁₇H₃₄. In the free troposphere, compounds heavier than n-C₂₂H₄₆ are fixed only at the trace concentration level. Redistribution of the organic component of aerosol between the surface and boundary air layers occurs during the year.

The contribution of wildfires into the content of the organic component of aerosol is studied on the basis of data of two flight campaigns carried out along the route Novosibirsk - Yakutsk - Novosibirsk in 2012 and 2013. The campaign of 2012 took place under conditions of extensive wildfires in Siberia, the campaign of 2013, on the contrary, in background conditions. The analysis of the selected aerosol samples shows that concentration of organic compounds during fires increases on the average by 35 times in the surface air layer and from 3 to 23 times in the free atmosphere in comparison with the background conditions. The composition of the organic component in the free atmosphere during fires changes depending on the region. At the Tomsk - Mirnyi segment, alkanes n-C₁₉H₄₀ - n-C₂₁H₄₄ prevailed in the aerosol samples; from Mirnyi to Yakutsk, the main concentration peak fell in the range of high-molecular compounds n-C₁₉H₄₀ - n-C₂₅H₅₂; at the Bratsk - Novosibirsk segment, low-molecular alkanes n-C₁₂H₂₆ -_{n-C18H38 prevailed in the aerosol composition.}

The functional composition and electrochemical behavior of the samples of N121 oxidized nanodisperse technical carbon in aqueous electrolytes are studied. For oxidation 30% aqueous hydrogen peroxide (H₂O₂) solution and 2% H₂O₂ with the addition of singlet oxygen or ozone were used. By means of X-ray photoelectron spectroscopy data and the analysis of the near edge X-ray absorption fine structure the features of the chemical structure of the samples are found. The oxygen concentration did not exceed 5 at.% in the samples. The analysis of cyclic voltammograms reveals that at low potential sweep rates the specific capacity of the material is determined by the functional composition of the surface. The sample oxidized by 30% H₂O₂ solution and containing the largest number of -OH and -COOH groups demonstrated the highest capacity in 6M KOH and in 1М H₂SO₄ it was the sample with the highest concentration of C=O groups formed during the oxidation with singlet oxygen. The stability of carbon electrodes is studied in supercondensor models.

The work reports the study of the structure of carbon nanoparticles prepared by pyrolysis of helium-diluted acetylene under adiabatic compression in a piston reactor. At a pushing gas pressure of 0.5 MPa, 0.7 MPa, and 0.9 MPa the reaction gas heated to a temperature of 400° C, 600° C, and 750° C. By transmission electron microscopy it is found that carbon nanoparticles have a spherical form and their size varies from 20 nm to 60 nm. The structural features of carbon nanoparticles are determined from the Xray photoelectron spectroscopy data and the analysis of near-edge Xray absorption fine structure. Carbon nanoparticles prepared at a pushing gas pressure of 0.5 MPa have an amorphous structure and consist of hydrogenated carbon with an impurity of polycyclic aromatic fragments. At a stronger compression ratio, carbon nanoparticles with a layered structure consisting of mainly sp ² hybridized carbon atoms form. The capacitance properties and electrochemical impedance of electrodes based on carbon nanoparticles in supercapacitors are compared.

Monolayer carbon framework nanoparticles (nanohorns) (CNHs) are synthesized by two methods: electric arc and electron evaporation of graphite in the inert atmosphere. Based on the data of electron microscopy and Raman light spectroscopy distinctions in the structures of materials obtained by different methods are revealed. By X-ray photoelectron and NEXAFS spectroscopy a change in the chemical structure of the CNH surface during their oxidation is considered. It is found that oxidation causes the destruction of CNH agglomerates and weakly affects the structure of graphene nets. However, these changes are sufficient for an increase in the infrared radiation absorption by the dispersion of nanohorns in water. It is shown that the efficiency of laser heating with a wavelength of 808 nm of CNH dispersion depends on the synthesis method and chemical modification of nanoparticles, which enables their potential use for local hyperthermia of cells of living organisms in cancer therapy.

The Cu(II)GHK (Cu(II)-Gly-His-Lys (glycyl-hystidyl-lysine) complex is of interest as a model peptide for the elaboration of a procedure to study the structure of metal centers in proteins, in particular, the copper binding center in β-amyloid. X-ray absorption spectra are measured for an aqueous solution of Cu(II)GHK. The stability of the complex under X-ray radiation is controlled by optical spectroscopy. Structural models with different coordinations of the copper center, which were constructed based on the crystallographic structure, are considered. Based on the analysis of theoretical X-ray absorption spectra of the derived structures, two optimal models are chosen. For the selected models the structural parameters are optimized. It is found that the best agreement with the experiment is observed for the spectrum of a five-coordinated model with water molecules in the equatorial and lower axial positions with Cu-O distances of 1.97 Å and 2.31 Å respectively.

The electronic energy structures of three phosphorus-containing sulfides are studied from the experimental K and L_2,3 X-ray emission spectra, K absorption spectra of sulfur and phosphorus, X-ray photoelectron spectra, and also quantum chemical calculations based on density functional theory (DFT). The full-potential and all-electron quantum chemical calculations are carried out using the LAPW+lo basis set implemented in the WIEN2k software package [1]. The following exchange-correlation potentials are used for the calculations: PBE, PBE+U, and mBJ [2]. The spin-orbit coupling of Tl 5d_3/2 and 5d_5/2 electronic states are taken into account in Tl₃PS₄. All the specific features of the electronic energy structures of the compounds under study are determined in the valence and conduction bands near the Fermi level. The obtained band gaps Eg are in good agreement with the literature experimental data.

A series of Cu, Ni, and Mn complexes based on formylpyrone and formylcoumarine azomethynes with 1,3-diaminepropanol-2. The analysis of XANES and EXAFS spectra of the Cu, Ni, and Mn complexes, which were processed by both Fourier and wavelet transforms, enables the determination of local atomic structural parameters and the unambiguous evidence of the formation of both dimeric and monomeric structures for these coordination compounds. The possibility of forming binuclear compounds is shown to depend mainly on the nature of the bridging ligand and be independent of the type of the polydentate azomethyne ligand: pyrone or coumarine. The obtained structural results are well consistent with the magnetochemical data for the complexes.

Nanocomposite systems based on ternary semiconductor compounds ZnS _x Se_1-x with different compositions (x = 0, 0.3, 0.5, 0.7, 1) in dielectric matrices of nanoporous anodic alumina (AA) are synthesized by ultrahigh vacuum thermal sputtering of a mixture of lead sulfide and selenide powders. The effect of the atomic concentration of solid solutions and structural parameters of the AA template matrix on the crystal structure of synthesized nanocomposites and the local atomic environment of Zn and Se atoms is investigated.