Аннотация

1.

Zhigzhitzhapova, S.V. Chemical composition of volatile organic compounds of Artemisia vulgaris L. (Asteraceae) from the Qinghai-Tibet Plateau / S.V. Zhigzhitzhapova, L.D. Radnaeva, Q.B. Gao et al. // Industrial Crops and Products. – 2016. – Vol. 83. – P. 462-469. https://doi.org/10.1016/j.indcrop.2015.12.083 (IF JСR=5,645 (3,181); Q1). https://www.webofscience.com/wos/woscc/full-record/WOS:000370894000059

Plants growing in different climate retain the general direction of the biosynthesis of the volatile organic compound (VOC). The aim of this study was to investigate the VOC composition in Artemisia vulgaris L. growing on the Qinghai–Tibet Plateau. The VOCs were isolated by hydrodistillation or by headspace extraction, and their composition was analyzed by gas chromatography–mass spectrometry (GC–MS). There were 96 VOCs identified in the samples, accounting for 91–97% of the total. Monoterpenes (80.33%) were the main components of VOCs released by headspace extraction. The major components of essential oil obtained by hydrodistillation were monoterpenes (44.49%) and sesquiterpenes (29.98%). The monoterpenes 1,8-cineole, camphor, and α- and β- thujones were the main VOCs detected after both hydrodistillation and headspace extraction. Sesquiterpenes (cis-davanone, germacrene D) also accounted for a significant proportion of compounds in the essential oil. A principal component analysis (PCA) based on the types of components of essential oils of A. vulgaris collected from different countries showed that the moisture conditions at the collection site was the main factor explaining variations in VOC composition, and were located between “European” and “Siberian” chemotype, which indicated that the essential oil profile does not fully reflect zonal climatic features.

2.

Stelmakh S.A., Ukshe A.E., Mognonov D.M., Novikova K.S., Grigor'eva M.N., Kayumov R.R., Bal'zhinov S.A., Dobrovolsky Y.A. Proton conductivity of new type medium-temperature proton exchange membranes // Ionics. – 2016. – Vol.22 (№10). – pp.1873–1880. Doi: 10.1007/s11581-016-1722-1 (IF JCR=1.754; Q2)

https://link.springer.com/content/pdf/10.1007/s11581-016-1722-1.pdf

This work reports on the analysis of physicochemical properties including proton conductivity of a new class of composite proton exchange membranes based on N-phenyl-substituted polyhexamethylene guanidine (PHMG) and poly-m-phenylene isophthalamide (phenylone) doped with phosphoric acid (PHMGP-PA) at different temperatures and environmental humidity. The presence of a strong ionic bond between protonated PHMGP and phosphoric acid anions allowed one to expect that the composite material is capable to retain phosphoric acid even in conditions of high humidity and temperature.

3.

Reshak, A. H. Electronic structure of monoclinic - Exploration of the Electronic Structure of Monoclinic α-Eu2(MoO4)3: DFT-Based Study and X-ray Photoelectron Spectroscopy / A.H. Reshak, Z.A. Alahmed, J. Bila, V.V. Atuchin, B.G. Bazarov, O.D. Chimitova, M.S. Molokeev, I.P. Prosvirin, A.P. Yelisseyev // J. Phys. Chem. C. – 2016, V. 120, № 19. – Р. 10559−10568. DOI: 10.1021/acs.jpcc.6b01489 (IF JCR 4.536 (2016); Q1).

https://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b01489

The powder α-Eu₂(MoO₄)₃ sample was prepared by the solid-state reaction method. The phase purity of the final powder product was verified by X-ray diffraction analysis. The constituent element core levels and valence band are measured by X-ray photoelectron spectroscopy as a function of Ar⁺ ion (2.5 keV, 7–8 μA/cm²) bombardment time. The formation of Mo⁵⁺ and Mo⁴⁺ states at high bombardment times was detected. The Eu–O and Mo–O bonding was considered in comparison with other Eu³⁺- and Mo⁶⁺-containing oxides using binding energy difference parameters. The transparency range obtained for the pure α-Eu₂(MoO₄)₃ tablet is λ = 0.41–0.97 μm, as estimated at the transmission level of 5%. The short-wavelength cut edge in α-Eu₂(MoO₄)₃ is governed by the direct allowed optical transitions within the band gap of E_g = 3.74 eV (300 K). The band structure of α-Eu₂(MoO₄)₃ was calculated by ab initio methods and strongly different results were obtained for the spin up/down configurations. The Eu-4f states are located around 2.2 eV and −4.0 eV for spin up (↑) and the structures situated at around 6.5 and 5.5 eV for spin down (↓) configuration. The calculated spin magnetic moments are in excellent relation to the Slater-Pauling rule and within the Eu sphere the magnetic moment of 4f electrons is ∼5.99 μB.

4.

Kotova, I.Yu. New series of triple molybdates AgA3R(MoO4)5 (A = Mg, R = Cr, Fe; A = Mn, R = Al, Cr, Fe, Sc, In) with framework structures and mobile silver ion sublattices / I.Yu. Kotova, S.F. Solodovnikov, Z.A. Solodovnikova, D.A. Belov, S.Yu. Stefanovich, A.A. Savina, E.G. Khaikina // J. Solid State Chem. – 2016. – V. 238. – P. 121–128. http://dx.doi.org/10.1016/j.jssc.2016.03.003 (IF JCR 2.299; Q2).

https://www.sciencedirect.com/science/article/pii/S0022459616300780?via%3Dihub

Triple molybdates AgA₃R(MoO₄)₅ (A=Mg, R=Cr, Fe; A=Mn, R=Al, Cr, Fe, Sc, In) of the NaMg₃In(MoO₄)₅ type were synthesized and single crystals of AgMg3R(MoO₄)₅ (R=Cr, Fe) were grown. In their structures, the MoO4 tetrahedra, pairs and trimers of edge-shared (Mg, R)O₆ octahedra are connected by common vertices to form a 3D framework. Large framework cavities involve Ag+ cations disordered on three nearby positions with CN=3+1 or 4+1. Alternating (Mg, R)O₆ octahedra and MoO4 tetrahedra in the framework form quadrangular windows penetrable for Ag+ at elevated temperatures. Above 653–673 K, the newly obtained molybdates demonstrate abrupt reduction of the activation energy to 0.4–0.6 eV. At 773 K, AgMg3Al(MoO4)5 shows electric conductivity 2.5·10−2 S/cm and Ea=0.39 eV compatible with characteristics of the best ionic conductors of the NASICON type.

5.

Zolotova, E.S. Phase relations in the Na2MoO4–Cs2MoO4 and Na2MoO4–Cs2MoO4–ZnMoO4 systems, crystal structures of Cs3Na(MoO4)2 and Cs3NaZn2(MoO4)4 / E.S. Zolotova, V.N. Yudin, S.F. Solodovnikov, E.G. Khaikina, O.M. Basovich, I.V. Korolkov, I.Yu. Filatova // J. Solid State Chem. – 2016. – V. 233. – P. 23–29. https://doi.org/10.1016/j.jssc.2015.10.008 (IF JCR- 2.299; Q2).

https://www.sciencedirect.com/science/article/pii/S0022459615301973?via%3Dihub

The phase diagram of the Na2MoO4-Cs2MoO4 system was reinvestigated and a new intermediate compound, Cs3Na(MoO4)(2), melting incongruently at 510 degrees C was found. Its crystal structure (a=6.3461(2), c=8.2209(3) angstrom, sp. gr. P (3) over bar m1, Z=1, R=0.0131) belongs to the glaserite type. Taking into account these data, the subsolidus phase relations of the system Na2MoO4-Cs2MoO4-ZnMoO4 was studied at 420 degrees C. The filling vacancies in the tetrahedral Zn position of the Cs6Zn5(MoO4)(8) structure (sp. gr. 1 (4) over bar 3d, Z=2) following the scheme Zn2+ +square -> 2Na(+) was established to result in the continuous solid solution Cs6Zn5-x square Na-1-x(2x)(MoO4)(8) (0 <= x <= 1). With increasing the x value, the cubic lattice parameter of the solid solution increases linearly while its melting point decreases that testifies to destabilization of the Cs6Zn5(MoO4)(8) structure by a progressive Na+ insertion. In the structure of Cs3NaZn2(MoO4)(4) (a=12.3134(1) angstrom, R=0.0121), Mo04 and (Zn2/3Na1/3)O-4 tetrahedra share corners to form an open 3D framework. The cesium ions are disordered around the centers of the cuboctahedral cavities of the framework to form "clusters" of the central Cs(1) and four disordered Cs(2) positions.

6.

Tsyrenova, G.D. New ferroelastic K2Sr(MoO4)2: Synthesis, phase transitions, crystal and domain structures, ionic conductivity / G.D. Tsyrenova, E.T. Pavlova, S.F. Solodovnikov, N.N. Popova, T.Yu. Kardash, S.Yu. Stefanovich, I.А. Gudkova, Z.A. Solodovnikova, B.I. Lazoryak // // J. Solid State Chem. – 2016. – V. 237. – P. 64–71. https://doi.org/10.1016/j.jssc.2016.01.011 (IF JCR- 2.299; Q2).

https://www.sciencedirect.com/science/article/pii/S0022459616300123?via%3Dihub

K2Sr(MoO4)(2) crystals were synthesized and their properties examined. The distortive polymorphic transformations at 421 K (alpha (LT) -> beta(MT)) and 744 K (beta(MT)->gamma (HT)) of K2Sr(MoO4)(2) were studied. It has been shown that the transitions go in sequence from the high-temperature palmierite K2Pb(SO4)(2)-type gamma-phase (R (3) over barm) to an intermediate beta-phase with a probable incommensurate structure and then to a low-temperature alpha-phase. Domain structures peculiarities in ferroelastic alpha-K2Sr(MoO4)(2) have been investigated. The electrical conductivity of K2Sr(MoO4)(2) rises tenfold in the vicinity of the phase transition at 744 K that may be associated with a change conductivity path from quasi-one-dimensional to two-dimensional. The crystal structure of the alpha-phase (sp. gr. C2/c, a=14.318(3) angstrom, b=5.9337(12) angstrom, c=10.422(2) angstrom, beta=105.83(3)degrees, Z=4, R=0.0219) is similar to that of alpha-Pb-3(PO4)(2). Sr atoms are mainly located at site with the coordination number CN=8 (a tetragonal antiprism with bond lengths of 2.578(2)-2.789(2) angstrom) and K atoms are located at site with CN=9+1.

7.

Stelmakh S.A., Ukshe A.E., Mognonov D.M., Novikova K.S., Grigor'eva M.N., Kayumov R.R., Bal'zhinov S.A., Dobrovolsky Y.A. Proton conductivity of new type medium-temperature proton exchange membranes. Ionics V22, №10, 1873–1880 – 2016. Doi: 10.1007/s11581-016-1722-1 (IF=1.754, Q2) https://link.springer.com/content/pdf/10.1007/s11581-016-1722-1.pdf

Among polymer fuel cells (FC), there is a class of devices where phosphoric acid is used as electrolyte. The retention of acid in a polymer matrix is provided by binding a part of its molecules with basic groups of the polymer. Operating temperature for such medium-temperature FC can attain 150 °C due to high thermal stability and relatively high proton conductivity at low humidity [1]. Increased operating temperature of such FC provides many advantages as compared with low-temperature FC with solid polymer membranes, among which increased tolerance of catalytic materials to CO poisoning is one of the most important parameters. Moreover, high temperature facilitates the organization of water management in the fuel cell: the water does not condense in the liquid phase, and there is no danger of flooding of electrode pores during operation. Thus, CO-enriched hydrogen produced by the reforming of natural gas, other hydrocarbon feedstocks, and alcohols can be used for their work [2, 3].

Nowadays, the most developed polymer electrolyte membranes for medium temperature FC are based on various condensation polymers, composite materials, polymers with nitrogen-containing heterocycles, and complexes of polymers with acids [4]. For medium- and high-temperature FC, the most studied proton conductive membranes are those based on polybenzimidazole (PBI) and its derivatives doped by phosphoric acid [5, 6]. Such membranes show high thermal stability and proton conductivity in the absence of water. However, the major drawback of these materials is associated with acid leaching [7]. Condensation of water vapor formed by the FC operation, for example, by stopping and cooling the battery, leads to phosphoric acid leaching from the electrolyte and its degradation, and penetration of acid on the structural elements leads to corrosion of the latter [8–10]. Thus, the search for new polymer materials that can safely hold the acid anion is one of the important tasks of developing medium-temperature FC.

This work reports on the analysis of physicochemical properties including proton conductivity of a new class of composite proton exchange membranes based on N-phenyl-substituted polyhexamethylene guanidine (PHMG) and poly-m-phenylene isophthalamide (phenylone) doped with phosphoric acid (PHMGP-PA) at different temperatures and environmental humidity. The presence of a strong ionic bond between protonated PHMGP and phosphoric acid anions allowed one to expect that the composite material is capable to retain phosphoric acid even in conditions of high humidity and temperature.

2017

11.

Radnaeva, L. D. Fatty acid composition in the white muscle of Cottoidei fishes of Lake Baikal reflects their habitat depth/ L. D. Radnaeva, D. V. Popov, O. Grahl-Nielsen, I. V. Khanaev, S. V. Bazarsadueva, R. Käkelä. // Environmental Biology of Fishes. – 2017. – V. 100, Issue 12. – P. 1623-1641. https://doi.org/10.1007/s10641-017-0670-6 (IF JСR=1,844 (1,514); Q1). https://www.webofscience.com/wos/woscc/full-record/WOS:000417067100010

Lake Baikal is a unique freshwater environment with maximum depths over 1600 m. The high water pressure at the lakebed strengthens the solidifying effect of low water temperature on animal tissue lipids, and thus the effective temperatures in the depths of the lake equal subzero temperatures in shallow waters. Cottoidei species has colonized the different water layers of the lake, and developed different ecology and physiology reflected in their tissue biochemistry. We studied by gas chromatography the composition of fatty acids (FAs), largely responsible for tissue lipid physical properties, in the white muscle tissue of 13 species of the Cottoidei fish; five benthic abyssal, six benthic eurybathic and two benthopelagic species. The FA profiles reflected habitat depth. The muscles of the deepest living species contained little polyunsaturated FAs (PUFAs) and were instead rich in monounsaturated FAs (MUFAs), which may be due to occasional weak food web links to the PUFA-rich primary producers of the photic water layer, high MUFA supply from their benthic diet, and conversion of saturated FAs (SFAs) to MUFAs in the tissues of the fish. Despite the MUFA percentage among the abyssal species reached even 50% (by weight) of total FAs, the PUFA percentage still remained above 20% in every species. The muscle MUFA/SFA ratio correlated negatively with the PUFA content of the fish muscle, suggesting viscosity control integrating the fluidity contributions from the dietary PUFAs and potentially endogenous MUFAs.

12.

New solid electrolyte Na9Al(MoO4)6: Structure and Na+ ion conductivity / A.A. Savina, V.A. Morozov, A.L. Buzlukov, I.Yu. Arapova, S.Yu. Stefanovich, Y.V. Baklanova, T.A. Denisova, N.I. Medvedeva, M. Bardet, J. Hadermann, B.I. Lazoryak, E.G. Khaikina // Chem. Mater. – 2017. – Vol. 29. – P. 8901–8913. https://doi.org/10.1021/acs.chemmater.7b03989 (IF JCR - 9.466; Q1)

https://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.7b03989

Solid electrolytes are important materials with a wide range of technological applications. This work reports the crystal structure and electrical properties of a new solid electrolyte Na9Al(MoO4)6. The monoclinic

Na9Al(MoO4)6 consists of isolated polyhedral [Al(MoO4)6]9− clusters composed of a central AlO6 octahedron sharing vertices with six MoO4 tetrahedra to form a three-dimensional framework. The AlO6 octahedron also

shares edges with one Na1O6 octahedron and two Na2O6 octahedra. Na3−Na5 atoms are located in the framework cavities. The structure is related to that of sodium ion conductor II-Na3Fe2(AsO4)3. High-temperature conductivity

measurements revealed that the conductivity (σ) of Na9Al(MoO4)6 at 803 K equals 1.63 × 10−2 S cm−1. The temperature behavior of the 23Na and 27Al nuclear magnetic resonance spectra and the spin-lattice relaxation rates of the 23Na nuclei indicate the presence of fast Na+ ion diffusion in the studied compound. At T<490 K, diffusion occurs by means of Na+ ion jumps exclusively through the sublattice of Na3−Na5 positions, whereas Na1 and Na2 become involved in the diffusion processes (through chemical exchange with the Na3−Na5 sublattice) only at higher temperatures.

13.

Luminescence properties upgrading via the structure and cation changing in AgxEu(2–x)/3WO4 and AgxGd(2–x)/3–0.3Eu0.3WO4 / V.A. Morozov, D. Batuk, M. Batuk, O.M. Basovich, E.G. Khaikina, D.V. Deyneko, B.I. Lazoryak, I.I. Leonidov, A.M. Abakumov, J. Hadermann // Chem. Mater. – 2017. – Vol. 29. – P. 8811–8823. https://doi.org/10.1021/acs.chemmater.7b03155 (IF - 9.466; Q1).

https://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.7b03155

The creation and ordering of A-cation vacancies and the effect of cation substitutions in the scheelite-type framework are investigated as a factor for controlling the scheelite-type structure and luminescence properties. AgxEu3+(2−x)/3□(1−2x)/3WO4 and AgxGd(2−x)/3−0.3Eu3+ 0.3□(1−2x)/3WO4 (x = 0.5−0) scheelite-type phases were synthesized by a solid state method, and their structures were investigated using a combination of transmission electron microscopy techniques and powder synchrotron X-ray diffraction. Transmission electron microscopy also revealed the (3 + 1)D incommensurately modulated character of AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.286, 0.2) phases. The crystal

structures of the scheelite-based AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.5, 0.286, 0.2) red phosphors have been refined from high resolution synchrotron powder X-ray diffraction data. The luminescence properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.5, 0.286,

0.2) phosphors show the strongest absorption at 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The excitation spectra of the Eu2/3□1/3WO4 and Gd0.367Eu0.30□1/3WO4 phases exhibit the highest contribution of the charge transfer band at 250 nm and thus the most efficient energy transfer mechanism between the host and the luminescent ion as compared to direct excitation. The emission spectra of all samples indicate an intense red emission due to the 5D0 → 7F2 transition of Eu3+. Concentration dependence of the 5D0 → 7F2 emission for AgxEu(2−x)/3□(1−2x)/3WO4 samples differs from the same dependence for the earlier studied NaxEu3+(2−x)/3□(1−2x)/3MoO4 (0 ≤ x ≤ 0.5) phases. The intensity of the 5D0 → 7F2 emission is reduced almost 7 times with decreasing x from 0.5 to 0, but it practically does not change in the range from x = 0.286 to x = 0.200. The emission spectra of Gd-containing samples show a completely different trend as compared to only Eu-containing samples. The Eu3+ emission under excitation of Eu3+(5L6) level (λex = 395 nm) increases more than 2.5 times with the increasing Gd3+ concentration from 0.2(x = 0.5) to 0.3 (x = 0.2) in the AgxGd(2−x)/3−0.3Eu3+0.3□(1−2x)/3WO4, after which it remains almost constant for higher Gd3+ concentrations.

14.

Cs3LiZn2(WO4)4 and Rb3Li2Ga(MoO4)4: different filled derivatives of the cation-deficient Cs6Zn5(MoO4)8 structure / S.F. Solodovnikov, Z.A. Solodovnikova, E.S. Zolotova, Yu.M. Kadyrova, A.A. Savina, S.Yu. Stefanovich, E.G. Khaikina // Acta Crystallogr. – 2017. – Vol. C73. – C. 73. – P. 946–952. https://doi.org/10.1107/S205322961701378X (IF JCR - 4.099; Q1).

https://onlinelibrary.wiley.com/iucr/doi/10.1107/S205322961701378X

Two new compounds, namely cubic tricaesium lithium dizinc tetrakis(tetraoxotungstate), Cs₃LiZn₂(WO₄)₄, and tetragonal trirubidium dilithium gallium tetrakis(tetraoxomolybdate), Rb₃Li₂Ga(MoO₄)₄, belong to the structural family of Cs₆Zn₅(MoO₄)₈ (space group I3d, Z = 4), with a partially incomplete (Zn_5/6□_1/6) position. In Cs₃LiZn₂(WO₄)₄, this position is fully statistically occupied by (Zn_2/3Li_1/3), and in Rb₃Li₂Ga(MoO₄)₄, the 2Li + Ga atoms are completely ordered in two distinct sites of the space group I2d (Z = 4). In the same way, the crystallographically equivalent A⁺ cations (A = Cs, Rb) in Cs₆Zn₅(MoO₄)₈, Cs₃LiZn₂(WO₄)₄ and isostructural A₃LiZn₂(MoO₄)₄ and Cs₃LiCo₂(MoO₄)₄ are divided into two sites in Rb₃Li₂Ga(MoO₄)₄, as in other isostructural A₃Li₂R(MoO₄)₄ compounds (AR = TlAl, RbAl, CsAl, CsGa, CsFe). In the title structures, the WO₄ and (Zn,Li)O₄ or LiO₄, GaO₄ and MoO₄ tetrahedra share corners to form open three-dimensional frameworks with the caesium or rubidium ions occupying cuboctahedral cavities. The tetrahedral frameworks are related to that of mayenite 12CaO·7Al₂O₃ and isotypic compounds. Comparison of isostructural Cs₃MZn₂(MoO₄)₄ (M = Li, Na, Ag) and Cs₆Zn₅(MoO₄)₈ shows a decrease of the cubic lattice parameter and an increase in thermal stability with the filling of the vacancies by Li⁺ in the Zn position of the Cs₆Zn₅(MoO₄)₈ structure, while filling of the cation vacancies by larger Na⁺ or Ag⁺ ions plays a destabilizing role. The series A₃Li₂R(MoO₄)₄ shows second harmonic generation effects compatible with that of β′-Gd₂(MoO₄)₃ and may be considered as nonlinear optical materials with a modest nonlinearity.

15.

Synthesis, crystal structures and properties of the new compounds K7–xAg1+x(XO4)4 (X = Mo, W) / T.S. Spiridonova, S.F. Solodovnikov, A.A. Savina, Z.A. Solodovnikova, S.Yu. Stefanovich, B.I. Lazoryak, I.V. Korolkov, E.G. Khaikina // Acta Crysallogr. – 2017.– Vol. C73. – Р. 1071–1077. https://doi.org/10.1107/S2053229617015674 (IF JCR - 4.099; Q1).

https://onlinelibrary.wiley.com/iucr/doi/10.1107/S2053229617015674

Two new isostructural compounds, namely heptapotassium silver tetrakis (tetraoxomolybdate), K_7–xAg_1+x(MoO₄)₄ (0 ≤ x ≤ 0.4), and heptapotassium silver tetrakis(tetraoxotungstate), K_7–xAg_1+x(WO₄)₄(0 ≤ x ≤ 0.4), have been synthesized and found to crystallize in the polar space group P6₃mc (Z = 2) with the unit-cell dimensions a = 12.4188 (2) and c = 7.4338 (2) Å for K_6.68Ag_1.32(MoO₄)₄ (single-crystal data), and a = 12.4912 (5) and c = 7.4526 (3) Å for K₇Ag(WO₄)₄ (Rietveld analysis data). Both structures represent a new structure type, with characteristic [K1(XO₄)₆] `pinwheels' of K1O₆ octahedra and six XO₄ tetrahedra (X = Mo, W) connected by common opposite faces into columns along the c axes. The octahedral columns are linked to each other through Ag1O₄ tetrahedra along with the K2 and K3/Ag2 polyhedra, forming the polar rods (Ag1O₄–X1O₄–empty octahedron–Ag1O₄). Ag1 is located almost at the centre of the largest face of its coordination tetrahedron and seems to have some mobility. The new structure type is related to the Ba₆Nd₂Al₄O₁₅ and CaBaSiO₄ types, and to other structures of the α-K₂SO₄–glaserite family. The differential scanning calorimetry (DSC) and second harmonic generation (SHG) results show that both compounds undergo first-order phase transformations to high-temperature centrosymmetric phases.

16.

A new double molybdate of erbium and zirconium, its crystalline structure and properties / B.G. Bazarov, J.G. Bazarova, Yu.L. Tushinova, L.A. Solovyov, S.G. Dorzhieva, E. Surenjav, J. Temuujin // Journal of Alloys and Compounds. – 2017. – Vol. 701. – P. 750 – 753. https://doi.org/10.1016/j.jallcom.2017.01.173 (IF - 3.133; Q1).

https://www.sciencedirect.com/science/article/pii/S0925838817301962?via%3Dihub

A new double molybdate of erbium and zirconium, Er₂Zr(MoO₄)₅ was synthesized by a simple solid-state reaction. The crystal structure was determined using powder X-ray diffraction data, the Rietveld method and the derivative difference minimization method (DDM). The new phase crystallizes in the orthorhombic space groupCmc2₁. Thedielectric properties and thermal expansion between 298 and 1073 K were investigated. The synthesized compound showed an electrical conductivity of about 10⁻² S cm⁻¹ at high temperature.

17.

Exploration of structural, thermal, vibrational and spectroscopic properties of new noncentrosymmetric double borate Rb3NdB6O12 / V.V. Atuchin, A.K. Subanakov, A.S. Aleksandrovsky, B.G. Bazarov, J.G. Bazarova, S.G. Dorzhieva, T.A. Gavrilova, A.S. Krylov, M.S. Molokeev, A.S. Oreshonkov, A.M. Pugachev, Yu.L. Tushinova, A.P. Yelisseyev // Advanced Powder Technology. – 2017. – V. 28, №5. – C. 1309–1315. https://doi.org/10.1016/j.apt.2017.02.019 (IF JCR - 2.659; Q1).

https://www.sciencedirect.com/science/article/pii/S0921883117300973?via%3Dihub

New noncentrosymmetric rare earth borate Rb₃NdB₆O₁₂ is found in the ternary system Rb₂O–Nd₂O₃–B₂O₃. The Rb₃NdB₆O₁₂ powder was fabricated by solid state synthesis at 1050 K for 72 h and the crystal structure was obtained by the Rietveld method. Rb₃NdB₆O₁₂ crystallized in space group R32 with unit cell parameters a = 13.5236(4), c = 31.162(1) Å, Z = 3. From DSC measurements, the reversible phase transition (I type) in Rb₃NdB₆O₁₂ is observed at 852–936 K. The 200 μm thick tablet is transparent over the spectral range of 0.3–6.5 μm and the band gap is found as E_g ∼ 6.29 eV. Nonlinear optical response of Rb₃NdB₆O₁₂ tested via SHG is estimated to be higher than that of K₃YB₆O₁₂. Blue shift of Nd luminescent lines is found in comparison with other borates. The vibrational parameters of Rb₃NdB₆O₁₂ are evaluated by experimental methods.

18.

Nonstoichiometry in the Systems Na2MoO4–MMoO4 (M = Co, Cd), Crystal Structures of Na3.36Co1.32(MoO4)3, Na3.13Mn1.43(MoO4)3 and Na3.72Cd1.14(MoO4)3, Crystal Chemistry, Compositions and Ionic Conductivity of Alluaudite-type Double Molybdates and Tungstates / S.F. Solodovnikov, Z.A. Solodovnikova, E.S. Zolotova, V.N. Yudin, O.A. Gulyaeva, Yu.L. Tushinova // Solid State Chem. – 2017. – Vol. 253. – P. 121–128. https://doi.org/10.1016/j.jssc.2017.05.031 (IF - 2.299; Q2).

https://www.sciencedirect.com/science/article/pii/S0022459617301998?via%3Dihub#f0015

As results of a powder XRD study of sintered samples of the systems Na₂MoO₄–MMoO₄ (M = Co, Cd) quenched in air from 873 K, the literature data on the phase formation andhomogeneity ranges of nonstoichiometric double molybdatesin these systems were corrected. The compounds aremonoclinic alluaudite-type Na_4-2xCo_1+x(MoO₄)₃ (0.05 ≤ x ≤ 0.30) and Na_4-2xCd_1+x(MoO₄)₃ (0.10 ≤ x ≤ 0.40), orthorhombic lyonsite-type Na_2-2yCo_2+y(MoO₄)₃ (0.05 ≤ y ≤ 0.25), andtriclinic Na_2-2zCo_2+z(MoO₄)₃ (0.10 ≤ z ≤ 0.40) of the Na₂Mg₅(MoO₄)₆ type. The temperature of the orthorhombic-to-triclinic phase transition was found to be 943 ± 10 K. Crystal structures of the alluaudite-type double molybdates (space group C2/c, Z = 4) with cobalt, manganese, and cadmium were determined. According to the atomic positionoccupations, the compositions for the crystals were found as Na_3.36Co_1.32(MoO₄)₃ (a = 12.6381(3), b = 13.4888(4), c = 7.1244(2) Å, β = 112.127(1)°_, R = 0.0207), Na_3.13Mn_1.43(MoO₄)₃(a = 12.7387(3), b = 13.6716(4), c = 7.1904(2) Å, β = 112.404(1)°,R = 0.0166), and Na_3.72Cd_1.14(MoO₄)₃ (a = 12.804(3), b = 13.913(3), c = 7.326(2) Å, β = 112.63(1)°_, R = 0.0158). The crystal chemistry and compositions of the alluaudite-type molybdates and tungstates were considered and mainly one-dimensional character of the sodium-ion transport was shown for them. The measured values of the ionic conductivity of sintered samples of Na_3.6M_1.2(MoO₄)₃ (M = Mg, Ni, Zn, Cd) and Na_3.6Mg_1.2(WO₄)₃ exceeds 10⁻³ S cm⁻¹ at 673 K.

19.

Savina A.A., Solodovnikov S.F., Belov D.A., Solodovnikova Z.A., Stefanovich S.Yu., Lazoryak B.I., Khaikina E.G. New alluaudite-related triple molybdates Na25Cs8R5(MoO4)24 (R = Sc, In): synthesis, crystal structures and properties // New J. Chem. 2017. Vol. 41. P. 5450–5457. DOI: 10.1039/c7nj00202e (IF JCR - 3.269; Q1)

.

https://pubs.rsc.org/en/content/articlepdf/2017/nj/c7nj00202e

New triple molybdates Na25Cs8R5(MoO4)(24) (R = Sc, In) were prepared as powders and ceramics by solid state reactions, and their single crystals were also obtained from melts by spontaneous crystallization. The structures were determined by single crystal XRD analysis. The electrical conductivity of ceramics was measured by impedance spectroscopy. The crystal structures were determined in monoclinic sp. gr. P2(1)/c, a = 14.0069(3) angstrom, b = 12.6498(3) angstrom, c = 28.6491(6) angstrom, beta = 90.007(1)degrees (Sc) and a = 14.0062(2) angstrom, b = 12.6032(2) angstrom, c = 28.7138(4) angstrom, b = 90.001(1)degrees (In). Together with triclinic Na25Cs8Fe5(MoO4)(24), the titled compounds form a distinctive family of pseudo-orthorhombic alluaudite-related structures with the parent sp. gr. Pbca. Its structural features are alluaudite-like polyhedral layers composed of pairs of edge-shared (R, Na)O-6 and NaO6 octahedra connected by bridging MoO4 tetrahedra. The layers are joined together by means of interlayer MoO4 tetrahedra, thus forming open 3D frameworks with cavities filled with Cs+ and Na+ ions. The manner of stacking layers is somewhat different from the alluaudite type. The compounds undergo phase transitions at 668 (Sc) and 725 (In) K accompanied by an abrupt increase of electrical conductivity presumably Na+-ionic in nature. Above these transitions, the conductivity is as high as 10(-3) S cm(-1), which makes Na25Cs8R5(MoO4)(24) (R = Sc, In) promising solid state electrolytes.

20.

Kholkhoev B.Ch., Baljinov S.A., Makotchenko V.G., Fedorov V.E., Farion I.A., Kozlova M.N., Timashev P.S., Burdukovskii V.F. Convenient approach to making nanocomposites based on a chitosan–poly(vinyl pyrrolidone) polymer matrix and a graphene nanofiller // J. Appl. Pol. Sci. – 2017. – V. 134. – № 27. – P. 45038. DOI 10.1002/app.45038 (IF - 3.125. Q2).

https://onlinelibrary.wiley.com/doi/10.1002/app.45038

Conducting, mechanically durable, elastic nanocomposite films were prepared with chitosan (CS) as the polymer matrix, graphene obtained from highly exfoliated graphite as the nanofiller, and poly(vinyl pyrrolidone) (PVP) as the stabilizer of the graphene sheets. The maximum graphene content in the composites without a loss of uniformity and other useful properties increased up to 4.0 wt %. The resulting composites were characterized by scanning electron microscopy, Raman spectroscopy, X-ray diffraction analysis, mechanical testing, and electrical conductivity testing to determine the effects of the addition of graphene on the morphology and mechanical and electrical properties of the CS–PVP–graphene nanocomposite films. In this study, we took an approach to making nanocomposites from the perspectives of green chemistry, environmental protection, regenerative medicine, and low cost.

21.

Oxidation of atrazine in aqueous media by solar- enhanced Fenton-like process involving persulfate and ferrous ion /M. Khandarkhaeva, A. Batoeva, D. Aseev, M. Sizykh, O. Tsydenova // Ecotoxicology and Environmental Safety.–2017.–Vol.137, №3.–P.35-41. https://doi.org/10.1016/j.ecoenv.2016.11.013 (IF JCR - 3.743, Q1)

https://www.sciencedirect.com/science/article/pii/S0147651316304663?via%3Dihub

The oxidation of s-triazines (using atrazine (ATZ) as a model compound) by a solar-enhanced Fenton-like process involving persulfate and ferrous ion was studied. A flow-through tubular photoreactor was employed for the experiments. The solar-enhanced oxidative system involving ferrous ion and persulfate (Solar/S₂O₈²⁻/Fe²⁺) showed the highest ATZ degradation efficiency when compared with other treatments (unactivated S₂O₈²⁻, Solar - sunlight only, S₂O₈²⁻/Fe²⁺, Solar/S₂O₈²⁻). Complete degradation of ATZ and 20% reduction in total organic carbon (TOC) content were observed after 30 min of the treatment. The in situ generated ^•ОН and SO₄^–• radicals were shown to be involved in ATZ oxidation using the radical scavengers methanol and tert-butyl alcohol. Furthermore, iron compounds were shown to act not only as catalysts but also as photo-sensitizers, as the introduction of ferrous ion into the reaction mixture led to an increased absorbance of the solution and expansion of the absorption spectrum into the longer wavelength spectral region.

22.

Khankhasaeva S., Dashinamzhilova E., Dambueva D. Oxidative degradation of sulfanilamide catalyzed by Fe/Cu/Al-pillared clays // Applied Clay Science. –2017. –Vol.146. –P.92-99. https://doi.org/10.1016/j.clay.2017.05.018.

(IF JCR - 3.065, Q1)

https://www.sciencedirect.com/science/article/pii/S0169131717302144.

An oxidative degradation of an antibiotic sulfanilamide with hydrogen peroxide was carried out in the presence of Fe/Cu/Al-pillared clays as heterogeneous Fenton type catalysts. Fe/Cu/Al-pillared clays were synthesized by intercalation of layered aluminosilicate containing 95 wt% montmorillonite with mixed polymeric Fe,Cu,Al-polyoxocations (Al/(Fe + Cu) = 10/1, OH/(Fe + Cu + Al) = 2.0 mol/mol). The materials were characterized by chemical analysis, low-temperature nitrogen adsorption and XRD. Fe/Cu/Al-pillared clays were active catalysts for sulfanilamide oxidation with hydrogen peroxide in aqueous solutions: in the presence of these materials oxidation rate increased significantly and conversion of sulfanilamide reached 99–100%. The effect of experimental factors such as H2O2/sulfanilamide molar ratio, the catalyst content, the reaction temperature and the pH on the conversion of sulfanilamide were studied. The optimal conditions for the catalytic oxidation of sulfanilamide in the presence of Fe/Cu/Al-pillared clay that permit achieving a high conversion of sulfanilamide and catalyst stability were determined. The Fe/Cu/Al-pillared clay could be used in four consecutive cycles without regeneration and loss of activity. The main intermediate products of sulfanilamide oxidative degradation were sulfanilic acid, benzenesulfonic acid, p-benzoquinone and aliphatic carboxylic acids. The results of the study proved that Fe/Cu/Al-pillared clays were effective catalysts for oxidative degradation of sulfanilamide in aqueous solutions.

23.

Chalov, S., Thorslund, J., Kasimov, N. et al. The Selenga River delta: a geochemical barrier protecting Lake Baikal waters // Regional Environmental Change 17, 2039–2053 (2017). https://doi.org/10.1007/s10113-016-0996-1 (IF JCR - 3,678, Q2)

https://link.springer.com/article/10.1007%2Fs10113-016-0996-1

The protection of Lake Baikal and the planning of water management measures in the Selenga River Basin require a comprehensive understanding of the current state and functioning of the delta’s ecosystem and hydrogeochemical processes. This is particularly relevant in light of recent and expected future changes involving both the hydrology and water quality in the Lake Baikal basin causing spatiotemporal changes in water flow, morphology, and transport of sediments and metals in the Selenga River delta and thus impacting on delta barrier functions. The central part of the delta had been characterized by sediment storage, especially along the main channels, causing a continuous lift of the delta surface by about 0.75 cm/year−1. Theses morphological changes have a significant impact on hydrological conditions, with historical shifts in the bulk discharge from the left to the right parts of the delta which is distinguished by a relatively high density of wetlands. Regions with a high density of wetlands and small channels, in contrast to main channel regions, show a consistent pattern of considerable contaminant filtering and removal (between 77 and 99 % for key metals), during both high-flow and low-flow conditions. The removal is associated with a significant concentration increase (2–3 times) of these substances in the bottom sediment. In consequence, geomorphological processes, which govern the partitioning of flow between different channel systems, may therefore directly govern the barrier function of the delta.

24.

2018

25.

Tykheev, Z.A. Constituents of Essential Oil and Lipid Fraction from the Aerial Part of Bupleurum scorzonerifoliumWilld. (Apiaceae) from Different Habitats / Z. A. Tykheev, S. V. Zhigzhitzhapova, F. Zhang, V. V. Taraskin, O. A. Anenkhonov, L. D. Radnaeva, S. Chen. // Molecules.– 2018. – Issue 23, No. 6, 1496. https://doi.org/10.3390/molecules23061496. (IF JCR – 4,411; Q2).

https://doi.org/10.3390/molecules23061496

The essential oils and lipid fraction extracted