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Ilmenite, apatite, monazite, aeshynite-(Y), zircon, baddeleyite, thorianite, uraninite, and copper-containing native gold have been revealed in specific magnetite-chlorite-carbonate rocks and chloritolites in the Karabash ultrabasic massif in the South Urals. Dolomite from the magnetite-chlorite-carbonate rocks are characterized by a rather uniform isotope composition (δ¹³С = -0.9 to -1.9‰, δ¹⁸О = 11.5-13.6‰, ⁸⁷Sr/⁸⁶Sr = 0.70422-0.70469) corresponding to a mixture of sources: marine limestones and mantle fluids. We determined the isotope compositions of antigorite from serpentinites (δD = -79.1 and -89.6‰, δ¹⁸O = 7.4 and 7.6‰), of chlorite from chloritolites (δD = -57.8‰, δ¹⁸O = 7.8‰), and of magnetite-chlorite-carbonate rocks (δD = -59.2 and -69.6‰, δ¹⁸O = 6.4 and 5.9‰). The latter probably formed by the mechanism of filling of the free space at 480-280 ºC, and chloritolites were developed after serpentinites. Oceanic serpentinites, gabbros, limestones, and mantle fluids can be considered the source of material during the formation of magnetite-chlorite-carbonate rocks. A comparative analysis of the latter and the massif rodingites (chlograpites) bearing copper-containing gold was carried out. The established common features of these types of rocks are the localization in zones of tectonic melange, the presence of chloritolite rims, geochemical specialization, thermal conditions of formation, and isotope parameters of minerals and fluids.

The source spectra of M = 4.0-6.5 subduction earthquakes of 2011-2014 in Kamchatka are studied. The dataset comprises 1272 source spectra recovered from S waves of 372 earthquakes recorded by six digital rock-ground stations. The structure of the spectra is examined on the basis of a spectral model with three corner frequencies f_c1, f_c2 , and f_c3. It was assumed that the spectra behave as f ^-2 between f_c2 and f_c3, where f_c3 denotes source-controlled f _max after Aki and Gusev. To determine the corner frequencies, we extracted the source spectrum from S- wave spectra using a previously developed attenuation model for the study area. The spectra were first reduced to the reference hard-rock station, employing a specially determined set of spectral amplifications of stations. We approximated the recovered source spectrum by a piecewise power-law function, estimated f_c1, f_c2, and f_c3, and examined their dependence on the seismic moment M ₀ (i.e., scaling). The dependence f_c1 (M ₀) does not contradict the hypothesis of source similarity when one expects . For f_c2 and f_c3, the scaling is close to and , respectively, indicating a clear violation of the similarity, especially prominent for f_c3. Systematic identification of the frequency f_c3, its determination, and analysis of its scaling are the main results of the study, important for understanding the physics of earthquake source processes. The use of f_c3 as a source parameter in strong ground motion simulations will eliminate biases in estimating attenuation parameters, in particular, the spectral decay parameter «kappa».

We present results of the first research into the thermal regime of the water column of man-made Lake Atomic (Semipalatinsk test site) performed in 2013-2015. The temperature data have shown a two-layer stratification of the water column. In the upper layer (0-30 m) there are significant yearly temperature variations caused by seasonal climatic changes and wind-wave mixing. In the lower layer (30-80 m) there is a stable nonlinear temperature distribution. This lake can be classified as meromictic, whose upper layer consists of weakly mineralized «light» water and lower one, of highly mineralized «heavy» water. This stratification prevents seasonal mixing of waters of the entire column (from surface to bottom).

This paper touches upon the problems of constructing a basis for stochastic functions, which represent samples of random numbers with a given distribution law. The algorithm for constructing an approximation model with the use of this basis is described. The general algorithm for signal recovery using the stochastic basis by the least squares method with a given weight function is given. The approach to solving the problem of recovery of blurred images with a known point scattering function by constructing an inverse filter model is proposed.

The electronic structure of three aza-boron-dipyridomethene derivatives containing different hydrocarbon groups at the boron atom is studied by ultraviolet photoelectron spectroscopy and calculations at the density functional theory level. According to the experimental and theoretical data, the higher occupied molecular orbitals of anthracene, acridine, and the studied complexes are of the same character. For the three studied compounds, the effect of alkyl and phenyl substituents on the electronic structure is determined. The parameters of the electronic structure of aza-boron-dipyridomethene (phenyl groups at the boron atom) and its b-diketonate analogue are compared. It is shown that in an energy range up to 11 eV the calculated results correlate with the ultraviolet photoelectron spectra.

A brief review of the results of studying some classes of nitrogen-containing chelate boron complexes by ultraviolet photoelectron spectroscopy and density functional theory is reported. The quantum chemical modeling of the substitution effects of a complexing agent, heteroatoms, and functional groups in α, β, and γ positions of the chelate ring allowed us to establish the features of the electronic structure of the studied complexes. It is found that the substitution of heteroatoms in the chelate ring has no substantial influence on the structure of the highest occupied molecular orbital (HOMO). In imidoylamidinate complexes, as opposed to formazanates and b-diketonates, there is no noticeable mixing of p orbitals of the chelate and benzene rings. In condensed nitrogen heterocycles the HOMO is stabilized by 0.2-0.3 eV and p orbitals of the benzene ring are stabilized by 0.8-1.2 eV. The HOMO of substituted aza-boron-dipyridomethene correlates with anthracene and acridine p₇ orbitals, which causes the fine structure of the first band. It is shown that in an energy range below 11 eV the calculated results reproduce well the energy gaps between the ionization states of the complexes.

The infrared spectra of the complexes of boron difluoride acetylacetonate and its halogen-substituted derivatives F₂B(aaX) (X = H, Cl, Br, I) in the crystalline state are studied. The substituent effect on the geometry and force field of molecules is revealed from DFT/B3LYP quantum chemical calculations with the 6-311G( d , p ) basis set. The detailed assignment of IR absorption bands is performed based on the calculations of normal modes (NMs) and the potential energy distribution (PED). The bands most sensitive to the substituent nature belong to vibrations with prevalent involvement of ring CC and CO bonds and some low-frequency noncharacteristic NMs involving the Х atom. In support of the single crystal XRD data, intermolecular interactions have the strongest effect on the characteristic bands of the BF₂ moiety in the ranges 1280-1220 cm^-1 and 875-835 cm^-1; the sequences of IR band frequency shifts in a series of substituents corresponding to these interactions are reported.

The article examines the electronic structure and orbital nature of luminescence excitation in a series of molecular crystals with the general formula E _n AX₆, where E_n are organic and inorganic cations (diphenylguanidinium, guanidinium, and cesium); n is the number of cations; AX₆ are Te(IV) and Sb(III) anions; X are the atoms of halogens Cl or Br. The electronic structure of these molecular crystals is determined from the data of X-ray photoelectron spectroscopy of the core and valence levels and еру quantum chemical modeling фе the density functional theory level together with the previously obtained single crystal X-ray diffraction data.

The effect of an additional aromatic ligand on the electronic structure of nickel(II) and cobalt(II) bis-acetylacetonates is studied by XPS and DFT (B3LYP/def2-TZVPP). An analysis of atomic charges, the geometry of compounds, the electron density distribution, and the interaction of molecular orbitals of complex components allows the conclusion about the ionic nature of the bonding between the neutral ligand and the bis-chelate.