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For the first time, a mononuclear biligand complex of lanthanum nitrate with bicyclic bisurea (4,4,10,10-tetramethyl-1,3,7,9-tetraazospiro[5.5]undecane-2,8-dione, or spirocarbon, Sk) [La(C11H20N4O2)2(H2O)2··(NO3)3] (I) is synthesized and its structure is determined by direct single crystal XRD. The crystals of I are monoclinic: space group P21/c, a = 11.1989(15) Å, b = 13.015(2) Å, c = 24.153(2) Å, β = 101.129(12)°, V = 3454.3(8) Å3, dcalc = 1.618 g/cm3, Z = 4, CCDC 985760. The structure is molecular. The lanthanum cation is coordinated by two oxygen atoms of two organic ligand molecules, two water molecules, and three bidentate nitrate anions. The coordination number of lanthanum is ten; the coordination polyhedron is an irregular 10-vertex polyhedron. The crystal of I represents a non-merohedral twin with the components turned by 180° along the a axis; the relative weights of the components are 0.76:0.24. To confirm the purity of the sample of I, the powder XRD pattern was refined using the Rietveld method; the unit cell parameters at room temperature are as follows: a = 11.2777(4) Å, b = 13.0774(5) Å, c = 24.3453(9) Å, β = 101.129(3)°, V = 3523.0(2) Å3. © 2016, Pleiades Publishing, Ltd.

Paczwa M.,University Of Szczecin | Sapiga A.A.,Vernadsky Crimean Federal University | Olszewski M.,University Of Szczecin | Sergeev N.A.,University Of Szczecin | Sapiga A.V.,Vernadsky Crimean Federal University
Journal of Structural Chemistry | Year: 2016

The mobility of water molecules in natural natrolite (Na2Al2Si3O10∙2H2O) is investigated by the 1H NMR method. The spin-lattice relaxation times in the laboratory and rotating frames (T1 and T1ρ) are measured as a function of the temperature for a polycrystalline sample. From experimental T1 data it follows that at T > 286 K the diffusion of water molecules along channels parallel to the c axis is observed. From experimental T1ρ data it follows that at T > 250 K the diffusion of water molecules in transversal channels of natrolite is also observed. At a low temperature (T < 250 K) the dipolar interaction with paramagnetic impurities (presumably Fe3+ ions) becomes significant as a relaxation mechanism of 1H nuclei. © 2016, Pleiades Publishing, Ltd.

Oberemok V.V.,Vernadsky Crimean Federal University | Laikova K.V.,Vernadsky Crimean Federal University | Zaitsev A.S.,Vernadsky Crimean Federal University | Gushchin V.A.,Moscow State University | Skorokhod O.A.,University of Turin
Pesticide Biochemistry and Physiology | Year: 2016

Numerous studies suggest a cellular origin for the Lymantria dispar multicapsid nuclear polyhedrosis virus (LdMNPV) anti-apoptosis genes IAPs, thus opening a possibility to use the fragments of these genes for modulation of host metabolism. We report here the strong insecticidal and metabolic effect of single-stranded antisense DNA fragment from RING (really interesting new gene) domain of gypsy moth LdMNPV IAP-3 gene: specifically, on reduction of biomass (by 35%) and survival of L. dispar caterpillars. The treatment with this DNA fragment leads to a significantly higher mortality rates of female insects (1.7 fold) accompanied with the signs of apoptosis. Additionally, we show increased expression of host IAP-1, caspase-4 and gelsolin genes in eggs laid by survived females treated with RING DNA fragment accompanied with calcium and magnesium imbalance, indicating that the strong stress reactions and metabolic effects are not confined to treated insects but likely led to apoptosis in eggs too. The proposed new approach for insect pest management, which can be considered as advancement of "microbial pesticides", is based on the application of the specific virus DNA, exploiting the knowledge about virus-pest interactions and putting it to the benefit of mankind. © 2016 Elsevier B.V.

Shaposhnikov A.N.,Vernadsky Crimean Federal University | Prokopov A.R.,Vernadsky Crimean Federal University | Berzhansky V.N.,Vernadsky Crimean Federal University | Mikhailova T.V.,Vernadsky Crimean Federal University | And 6 more authors.
Optical Materials | Year: 2016

We have investigated the low-temperature behavior of the optical and magneto-optical properties of (Bi, Gd, Al)-substituted yttrium iron-garnet films that are either single or microresonator, i.e. sandwiched between two dielectric Bragg mirrors. It was shown that the magneto-optical properties of the microresonators with a magnetic film core are mainly determined by the properties of the constituent magnetic films. Special attention was paid to the compositions possessing magnetic compensation temperatures. The phenomenon of the temperature hysteresis was found and discussed for several samples. This testifies the fact that the magnetic moment reorientation in a magnetic field occurs by the full cycle of the first-order phase transitions "collinear phase - non-collinear phase - collinear phase". The Faraday hysteresis curves at around magnetic compensation temperatures are demonstrated to be very informative concerning composition of a sample. In particular, the hysteresis curves measured for the magnetic films on the garnet substrates showed bursts that indicates formation of a transition layer. © 2015 Elsevier B.V.

Prokopov A.R.,Vernadsky Crimean Federal University | Vetoshko P.M.,RAS Institute of Radio Engineering and Electronics | Shumilov A.G.,Vernadsky Crimean Federal University | Shaposhnikov A.N.,Vernadsky Crimean Federal University | And 5 more authors.
Journal of Alloys and Compounds | Year: 2016

Novel magneto-optical epitaxial bismuth-substituted iron garnet films of composition (BiGd)3(FeSc)5O12 with large lattice parameter of 12.570 Å have been grown and investigated. Their composition was uniquely chosen to get necessary values of the magnetic and magneto-optical parameters crucial for magneto-optical applications. In particular, the fabricated films have the suppressed cubic magnetic anisotropy (down to 1.2 × 103 erg/cm3) and the large magnetic susceptibility (∼50), due to introducing Sc3+ ions; the diminished saturation magnetization (4πMS ∼ 750 Gs), caused by Gd3+ ions, and relatively large specific Faraday rotation (1.75°/μm, at 655 nm), due to Bi3+ ions. Therefore, the grown magnetic films have record values of the product of the magnetic susceptibility by the Faraday rotation that makes them extremely promising for applications, including magnetometers, magneto-optical visualizers, light modulators and nonreciprocal elements of the integrated optics. © 2016 Elsevier B.V. All rights reserved.

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