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The article examines the methodological approach to the analysis of the demographic situation dynamics on several indicators for multiple territorial objects, allowing evaluating each territory according to the degree of the demographic situation tension in general. For this type of analysis several indicators of demographic threats has been selected, on which the dynamics for all regions of the Siberian Federal district (SFD) on the background of the all-Russian tendencies has been presented. The integral indicator of demographic security is also used (IIDS). Comparing the dynamics of IIDS for all subjects of the SFD three groups of regions in terms of demographic security in 1990-2013 are selected. It is shown that almost all regions with low demographic security are border territories of the Russian Federation, having the state borders with Kazakhstan, Mongolia and China.

The [Eu(HDTBA)₃] _n complex (I), HDTBA is 1,3-diethyl-2-thiobarbituric acid (C₈H₁₂N₂O₂S) is synthesized and its structure is determined by X-ray crystallography. The crystals of I are triclinic: a = 11.0205(2) Å, b = 11.8811(3) Å, c = 12.7312(2) Å, a = 100.933(1)°, b = 109.704(1)°, g = 101.161(1)°, V = 1479.88(5) ų, space group P -1, Z = 2. Each of three independent DETBA^- ions is a bridging m₂-O,O¢-coordinated ligand. The coordination polyhedron of Eu(III) is a distorted octahedron. Bridging DETBA^- organize the octahedra into an infinite two-dimensional layer. The structure contains intramolecular hydrogen bonds but intermolecular hydrogen bonds and the p-p interaction are absent. The results of IR spectroscopy and photoluminescence agree with the single crystal X-ray diffraction data. The main product of the thermal decomposition of I at 900°С is oxysulfate Eu₂O₂SO₄.

A structural interpretation of the catalytic action of carbon nanotubes on the curing of epoxy polymers is proposed. It is based on the fractal analysis ideas. It is shown that essentially the only factor determining the kinetics of the curing process is the microgel structure characterized by its fractal dimension. The most important conclusion from the obtained results is the fact that the reaction rate dependences on the structural parameters are described by the same correlation for the epoxy polymer curing reaction both in the presence and absence of carbon nanotubes. This means that the catalytic effect of carbon nanotubes consists in a change in the structure of microgels.

BaTi_{1- x} Nb _x O₃ compounds (with x = 0.00, 0.01, 0.03, 0.06, and 0.09) are synthesized by the microwave-hydrothermal (MH) method. The donor concentration effect on the structural properties is investigated. The new MH method is used instead of the previous solid state reaction for the BaTiO₃+Nb₂O₃ system. In the MH process, as the niobium incorporation rate increases, the particle growth substantially slows down. The synthesis of Nb-doped BaTiO₃ is investigated under the MH conditions subjected to 150 °C for only 2 h using C₁₆H₃₆O₄Ti (tetra-n-butyl orthotitanate), Ba(OH)₂×8H₂O, and NbCl₅ as Ba, Ti, and Nb sources respectively. For the phase evolution studies, X-ray diffraction patterns are analyzed and Raman spectroscopy is performed. The transmission electron microscope and the field emission scanning electron microscope images are taken for the detailed analysis of the grain size, surface, and morphology of the compound.

The [Co₂(tbb)Cl₄]×4DMF complex, where tbb is meso -1,2,3,4-tetra(1H-benzo[ d ]imidazol-2-yl)butane, is synthesized and characterized by single crystal X-ray diffraction. For the complex: C₄₄H₅₄Co₂C_l4N₁₂O₄, M_r = 1074.65, monoclinic crystal system, space group P 21/ n , a = 9.2350(13) Å, b = 11.3566(15) Å, c = 23.879(3) Å, b = 90.547(2)°, V = 2504.3(6) ų, Z = 2, D_c = 1.425 g/cm³, l = 0.71073 Å, m(Mo K _a) = 0.929 mm^-1, F (000) = 1112, S = 1.047, R = 0.0765, and wR = 0.2110 for 13668 observed reflections with I > 2 s( I ) . It is a neutral dinuclear complex. One meso -1,2,3,4-tetra(1H-benzo[ d ]imidazol-2-yl)butane coordinates two cobalt(II) ions. Each cobalt(II) ion is formed by two tbb nitrogen atoms and two chloride ions. The antiproliferative activities of the complex are screened by MTT assay against Eca109 cancer cells. The complex exhibits inhibition on the growth of Eca109 cancer cells with IC₅₀ of 22.1±6.7 mM after 48 h treatment. The cobalt complex has potential application in treatment of Eca109 cancer. CCDC 1015791.

We report the optical and structural properties of ZnO and MgO nanoparticles. The samples are obtained by a simple method using a new template of hexamethylene tetramine. The optical properties of the samples are studied by UV-visible spectroscopy. Their crystal structure and morphology are studied by XRD and scanning electron microscopy. The absorption spectra of MgO and ZnO show that the optical band gaps are 4.27 eV and 3.02 eV, respectively. In this investigation the photocatalytic degradation of indigo carmine (IC) in water is studied. The effects of some parameters such as pH, amount of catalyst, initial concentration of dye, are examined.

Tungsten tetraiodide WI₄ (1) is produced by a high-temperature reaction of WTe₂ and I₂ in a vacuum sealed ampoule. The crystals of 1 belong to the triclinic crystal symmetry, space group P -1, Z = 4, a = = 7.9291(3) Å, b = 10.7695(4) Å, c = 10.8117(4) Å, a = 85.668(1)°, b = 71.772(1)°, g = 71.559(1)°, V = = 831.60(5) ų, d _calc = 5.523 g/cm³. The structure of 1 consists of tetrameric W₄I₁₆ molecules in which W atoms are in a distorted octahedral environment formed by I atoms.

The crystal structure of nitrate tris(4-allylthiosemicarbazide)chromium(III) hydrate [CrL₃](NO₃)₃(H₂O)_1.05 (I) , where L is 4-allylthiosemicarbazide, is determined. The asymmetric unit of the cell of the crystal structure of I contains a complex of a chromium ion with three bidentate coordinated molecules L. The outer coordination sphere of the central atom contains a disordered water molecule and three nitrate ions. The coordination polyhedron of the chromium atom in complex I is an octahedron. In the crystal, the complexes of the compound under study are joined with each other by the outer-sphere nitrato groups into a three-dimensional branched net of hydrogen bonds.

For the first time the crystal structure and absolute configuration of 28- O -acetylbetulin are determined by the X-ray crystallographic analysis.

The crystal and molecular structures of 1-(iodmethyl)silatrane and 1-(iodpropyl)silatrane are determined by X-ray diffraction. The effect of the iodine heteroatom upon silatrane moieties of the molecules through one- and three-carbon chains is studied based on the geometric characteristics of the molecules and the analysis of their packings.