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Three minerals of the mayenite supergroup have been found in fluorellestadite-bearing metacarbonate rock (former fragment of petrified wood of ankerite composition) from the burned dump of the Baturinskaya-Vostochnaya-1-2 mine. These are eltyubyuite Ca ₁₂Fe ³⁺ ₁₀Si ₄O ₃₂Cl ₆, its fluorine analog Ca ₁₂Fe ³⁺ ₁₀Si ₄O ₃₀F ₁₀, and chlormayenite-wadalite Ca ₁₂(Al,Fe) ₁₄O ₃₂Cl ₂-Ca ₁₂(Al,Fe) ₁₀Si ₄O ₃₂Cl ₆. The first two phases occur in the reaction mantle around hematite, magnesioferrite, and Ca-ferrite aggregates (“calciohexaferrite” CaFe ₁₂O ₁₉, “grandiferrite” CaFe ₄O ₇, and “dorrite phase” Ca ₂(Fe ³⁺ ₅Mn ³⁺ _0.5Mg _0.5)(Si _0.5Fe ³⁺ _5.5)O ₂₀) and, rarely, as individuals in the fluorellestadite-cuspidine (± larnite ± rusinovite Ca ₁₀(Si ₂O ₇) ₃Cl ₂) granular aggregate. Assemblages of zoned chlormayenite-wadalite crystals are found in the fluorellestadite-cuspidine granular aggregate, which lacks Ca-ferrite aggregates. Also, harmunite CaFe ₂O ₄, chlorellestadite, fluorapatite, anhydrite, rondorfite Ca ₈Mg(SiO ₄) ₄Cl ₂, fluorine analog of rondorfite Ca ₈Mg(SiO ₄) ₄F ₂, “Mg-cuspidine” Ca _3.5(Mg,Fe) _0.5(Si ₂O ₇)F ₂, fluorite, barioferrite BaFe ₁₂O ₁₉, zhangpeishanite BaFCl, and other rare phases are identified in this rock. Data on the chemical composition and Raman spectroscopy of the mayenite supergroup minerals are given. The genesis of metacarbonate rock is considered in detail: “oxidizing calcination” of Ca-Fe-carbonates with the formation of hematite and lime; reaction between hematite and lime with the formation of different Ca-ferrites; formation of larnite as a result of reaction between SiO ₂ and lime or CaCO ₃; and reactionary impact of hot Cl-F-S-bearing gases on early assemblages. Eltyubyuite and its fluorine analog crystallized at the stages of gas impact. It is presumed that the maximum temperature during the formation of rock reached 1200-1230 ºC.

The 1370 km long 4-AR reference profile crosses the North Barents Basin, the northern end of the No-vaya Zemlya Rise, and the North Kara Basin. Integrated geophysical studies including common deep point (CDP) survey and deep seismic sounding (DSS) were carried out along the profiles. The DSS was performed using autonomous bottom seismic stations (ABSS) spaced 10–20 km apart and a powerful air gun producing seismic signals with a step size of 250 m. As a result, detailed P- and S-wave velocity structures of the crust and upper mantle were studied. The basic method was ray-tracing modeling. The Earth’s crust along the entire profile is typically continental with compressional wave velocities of 5.8–7.2 km/s in the consolidated part. Crustal thickness increases from 30 km near the islands of Franz Josef Land to 35 km beneath the North Barents Basin, 50 km beneath the Novaya Zemlya Rise, and 40 km beneath the North Kara Basin. The North Barents Basin 15 km deep is characterized by unusually low velocities in the consolidated crust: The upper crust layer with velocities of 5.8–6.4 km/s has a thickness of about 15 km beneath the basin (usually, this layer wedges beneath deep sedimentary basins). Another special property of the crust in the North Barents Basin is the destroyed structure of the Moho.

We studied changes in the properties of the geologic environment in the vicinity of the stationary 40-ton vibration source at time intervals between the vibration sessions. Experiments have shown that the quantity of the energy released in the environment with time depends on the frequency of an amplitude spectrum. We introduced parameter α characterizing this dependence and have established a linear regular increase in its module between the series of switch-on of the vibration source during the field observations. A hypothesis is put forward that there are zones that can rapidly change their stressed state, both accumulating and giving the accumulated energy. Comparative analysis of the stressed state of the experimental zone showed significant differences in the spatial distribution of the gradient of a new parameter (β) before and after active low-frequency impacts on the geologic environment.

The magnetic viscosity of geologic media exerts a significant, often high and sometimes predominant influence on the pulse induction characteristics measured in the laboratory and in the field. Compared with the frequency methods, measurement of pulse magnetization parameters has advantage, namely, magnetic viscosity is observed in the absence of the primary field, and the transitive pulse parameter is measured over a wide time range. This reduces the error of measurement of parameters characterizing magnetic viscosity. In contrast to the transitive parameter, its derivative, i.e., a pulse parameter, is not influenced by a constant (slowly decreasing) component of the total residual magnetization. This eliminates the problem of the uncertainty on the separation of low-viscosity component from the total magnetization. The temporal decrease in the pulse parameters of magnetization is described by the power function a · t-b , where a is the initial value (varies over a wide range) and b is the exponent close to unity. As shown by the measurements made with the use of induction coil systems, the parameter a shows a strong linear correlation with the frequency-dependent magnetic susceptibility Δ k , which is commonly used to evaluate the content of superparamagnetic particles. This suggests that the pulse induction systems can be used for an express study of a large number of samples in order to identify SP-particles and estimate their contents. Although the exponent b differs negligibly from unity, this difference is much higher than the error of determination of this parameter from the experimental data. Mathematical modeling of the pulse parameters of magnetization has shown that both are influenced by the distribution of the particle volume, which makes prerequisites for solving the inverse problem, i.e., finding the distribution that provides the best explanation of the experimental pulse parameters.

In this paper the results of magnetostratigraphic studies of the Upper Cretaceous penetrated by two wells (S-124 and S-114) drilled in the Tomsk structural-facies zone (Bakchar iron ore deposit) are presented. The obtained biostratigraphic data show that the sediments formed in the Campanian–Maastrichtian time in-terval. The high-temperature component of the remanent magnetization identified in the rocks allowed us to compile paleomagnetic columns for each well and correlate the columns, using paleontological data, with each other and with the general magnetostratigraphic and magnetochronological scales. In magnetostratigraphic sections of two wells, the Campanian reverse-polarity Slavgorod Formation (R(km)) with a normal-polarity horizon is correlated with Chron C33(r) (top) and C33(n) (bottom) of the Gradstein scale, and the Maas-trichtian normal-polarity Gan’kino Formation with a thin reverse-polarity horizon (N(mt)) is correlated with Chron C30 of this scale.

A two-parameter molecular descriptor is proposed in the QSPR model. It relates the ionization energies of molecules with topological indices and integrated oscillator strengths. Integrated oscillator strengths are obtained from electron spectroscopy data in the UV and visible spectral ranges. The regularities obtained are confirmed by the statistical processing of the data by multiple regression analysis methods in series of 1,4-naphthoquinone, 1-oxyanthraquinone, and 1-(4- tret-butylphenoxy)-9,10-anthraquinone derivatives.

Based on the full optimized molecular geometric structures at the B3LYP/cc-pVTZ level, a new designed compound 5-nitro-2-nitratomethyl-1,2,3,4-tetrazole is investigated in order to look for high energy density compounds (HEDCs). The IR spectrum, the heat of formation (HOF), and frontier molecular orbitals are predicted. The detonation velocity and pressure are evaluated using Kamlet-Jacobs equations based on the theoretical density and condensed HOF. The bond dissociation energies (BDEs) and bond orders for the weakest bonds are analyzed to investigate the thermal stability of the title compound. The results show that the O ₁-N ₆ bond is the trigger bond. The crystal structure obtained by molecular mechanics belongs to the Pna 2 ₁ space group with lattice parameters Z = 4, a = 13.7565 Å, b = 12.4737 Å, c = 4.3445 Å.

A newly synthesized Schiff base 3,3'-dihydroxy-4,4'-[4,4'-diphenylmethanebis(nitrilomethylidyne)]-bis-phenol is characterized experimentally. Also, the geometry optimization for the tautomers, tautomerism and assignment of the IR bands and NMR chemical shifts of the Schiff base were performed using the DFT method. Good consistency between the theoretical and experimental results confirms the validity of the optimized geometry. Geometries of four possible tautomers are fully optimized. None of them has a planar structure, but each of the benzene rings is in a separate plane. In the most stable tautomer L1, the phenolic protons are engaged in the intramolecular-hydrogen bond with the azomethine nitrogen atoms. Tautomerization of L1 can occur in two different pathways which are computationally studied using DFT and the Atoms In Molecules (AIM) analysis. Both pathways have the same barrier energy.

Random sampling analysis on the molecular surface (RASMS) is used to describe the chemical structures of 35 HEPT derivatives as anti-HIV drugs. Here a quantitative structure activity relationship (QSAR) model is built by multiple linear regression (MLR). The estimation stability and prediction ability of the model are strictly analyzed by both internal and external validations. The correlation coefficients of the established MLR model, leave-one-out (LOO) cross-validation, and predicted values versus experimental ones of external samples were r ² = 0.851, = 0.746, and r ²(test) = 0.815 respectively. The satisfactory results show that RASMS can express the information related to the biological activity of HEPT derivatives.

Results of a theoretical study of the molecular structure of arglabin are pesented. Quantum chemical calculations of the geometry and physicochemical characteristics of arglabin are performed by the semi-empirical РМ6 method, the non-empirical Hartree-Fock method, and the hybrid B3LYP DFT method with 6-31G and 6-31G( d ) basis sets. By the B3LYP/6-31G( d ) method the vibrational frequencies and intensities of IR absorption bands of arglabin are also calculated and the detailed interpretation of the IR spectrum is given. The theoretical frequencies are well consistent with the experimental data.