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111.
M. V. Dmitriev D. V. Ivanov N. M. Igidov R. R. Makhmudov V. V. Novikova I. N. Chernov 《Russian Journal of General Chemistry》2018,88(7):1397-1401
The previously unknown mono- and dibromo derivatives of 2-amino-5-(2-aryl-2-oxo-ethylidene)-4-oxo-1H-4,5-dihydrofuran-3-carboxylic acids were synthesized. Antinociceptive and antimicrobial activity of the obtained compounds was studied. 相似文献
112.
N. N. Novikova S. I. Zheludeva N. D. Stepina A. L. Tolstikhina R. V. Gaĭnutdinov A. I. Erko W. Haase Yu. G. Galyametdinov 《Crystallography Reports》2006,51(6):1041-1047
The molecular organization of Langmuir-Blodgett films based on the liquid crystal europium complex has been studied by the X-ray standing-wave method at the synchrotron radiation source BESSY (Germany). Analysis of the experimental data obtained made it possible to determine the composition of the organic multilayer nanosystems and localize the position of metal ions incorporated in organic layers from the aqueous subphase during film deposition. It is shown that, despite the low content of metal ions in the aqueous subphase (no higher than 10?7 mol/l), their incorporation into the Langmuir layer affects the molecular film organization significantly. 相似文献
113.
A. P. Dudka I. A. Verin V. N. Molchanov M. K. Blomberg O. A. Alekseeva N. I. Sorokina N. E. Novikova V. I. Simonov 《Crystallography Reports》2005,50(1):36-41
The structure of a K0.93Ti0.93Nb0.07OPO4 single crystal is studied at the temperature 30 K. The measurements are performed on a four-circle HUBER-5042 diffractometer with a DISPLEX DE-202 cryostat. Processing of the diffraction data and the preliminary refinement of the model are performed using the ASTRA program package. The final refinement of the structure model is made using the JANA2000 program complex. The refinement shows that the structure of a K0.93Ti0.93Nb0.07OPO4 crystal at T = 30 K is similar to its structure at room temperature. No phase transitions are revealed. Slight temperature-induced displacements of the potassium positions in the large cavities of the mixed framework are established. 相似文献
114.
Glycoclusters were obtained by N-alkylation of N-glycyl-β-d-galactopyranosylamine with N-chloroacetyl derivatives of β-d-galactopyranosylamine and N,N″-iminodiacetyl-di-β-d-galactopyranosylamine. The glycoclusters with two and three galactopyranosylamine residues and the monovalent ligand N-diglycyl-β-d-galactopyranosylamine with an amino group in the spacer are suitable for subsequent conjugation with carboxyl-containing
physiologically active compounds. 相似文献
115.
Stanislav N. Naryzhny Victor G. Zgoda Maria A. Maynskova Svetlana E. Novikova Natalia L. Ronzhina Igor V. Vakhrushev Elena V. Khryapova Andrey V. Lisitsa Olga V. Tikhonova Elena A. Ponomarenko Alexander I. Archakov 《Electrophoresis》2016,37(2):302-309
Virtual and experimental 2DE coupled with ESI LC‐MS/MS was introduced to obtain better representation of the information about human proteome. The proteins from HEPG2 cells and human blood plasma were run by 2DE. After staining and protein spot identification by MALDI‐TOF MS, the protein maps were generated. The experimental physicochemical parameters (pI/Mw) of the proteoforms further detected by ESI LC‐MS/MS in these spots were obtained. Next, the theoretical pI and Mw of identified proteins were calculated using program Compute pI/Mw ( http://web.expasy.org/compute_pi/pi_tool‐doc.html ). Accordingly, the relationship between theoretical and experimental parameters was analyzed, and the correlation plots were built. Additionally, virtual/experimental information about different protein species/proteoforms from the same genes was extracted. As it was revealed from the plots, the major proteoforms detected in HepG2 cell line have pI/Mw parameters similar to theoretical values. In opposite, the minor protein species have mainly very different from theoretical pI and Mw parameters. A similar situation was observed in plasma in much higher degree. It means that minor protein species are heavily modified in cell and even more in plasma proteome. 相似文献
116.
B. B. Troitskii A. A. Lokteva V. N. Denisova M. A. Novikova A. N. Konev I. L. Fedyushkin 《Russian Journal of Applied Chemistry》2016,89(7):1132-1136
The mean size of the latex particles formed in emulsion polymerization of methyl methacrylate under definite conditions (water: monomer volume ratio 15: 1, 80°C, potassium persulfate concentration 0.07 wt %) decreases from 200 to 9–10 nm as the concentration of an ionic surfactant (anionic Disponil AES 60, SDS, cationic C19H42BrN) is increased from 0.0 to 1.0 wt %. The nonionic surfactants studied influence the size of the latex particles formed differently: with ALM-10, the particle size decreases from 200 to 150–190 nm, whereas with ALM-7 and ALM-2 it increases from 200 to 320 nm as the surfactant concentration is increased from 0.0 to 1.0 wt %. An increase in the concentration of F127 amphiphilic ternary block copolymer from 0.0 to 1.0 wt % leads to a monotonic decrease in the size of the poly(methyl methacrylate) latex particles formed from 200 to 53 nm. 相似文献
117.
We describe how a top-like quantum Hamiltonian over a non-Lie algebra appears in the model of the planar Penning trap under the breaking of its axial symmetry (inclination of the magnetic field) and tuning parameters (electric voltage, magnetic field strength and inclination angle) at double resonance. For eigenvalues of the quantum non-Lie top, under a specific variation of the voltage on the trap electrode, there exists an avoided crossing effect and a corresponding effect of bilocalization of quantum states on pairs of closed trajectories belonging to common energy levels. This quantum tunneling happens on the symplectic leaves of the symmetry algebra, and hence it generates a tunneling of quantum states of the electron between the 3D-tori in the whole 6D-phase space. We present a geometric formula for the leading term of asymptotics of the tunnel energy-splitting in terms of symplectic area of membranes bounded by invariantly defined instantons. 相似文献
118.
N. N. Novikova M. V. Kovalchuk S. N. Yakunin O. V. Konovalov N. D. Stepina A. V. Rogachev E. A. Yurieva I. V. Marchenko T. V. Bukreeva O. S. Ivanova A. E. Baranchikov V. K. Ivanov 《Crystallography Reports》2016,61(5):857-865
The processes of structural rearrangement in a model membrane, i.e., an arachic acid monolayer formed on a colloidal solution of cerium dioxide or magnetite, are studied in situ in real time by the methods of X-ray standing waves and 2D diffraction. It is shown that the character of the interaction of nanoparticles with the monolayer is determined by their nature and sizes and depends on the conditions of nanoparticle synthesis. In particular, the structure formation in the monolayer–particle system is greatly affected by the stabilizer (citric acid), which is introduced into the colloidal solution during synthesis. 相似文献
119.
E. I. Orlova E. P. Kharitonova N. E. Novikova I. A. Verin O. A. Alekseeva N. I. Sorokina V. I. Voronkova 《Crystallography Reports》2010,55(3):404-411
Single crystals of potassium titanyl phosphate doped with hafnium are grown by spontaneous flux crystallization. Their physical
properties are studied, and the structure of three KTi1 − x
Hf
x
OPO4 crystals (x = 0.01, 0.03, and 0.12) is determined. In the crystals studied, hafnium mostly occupies the second titanium position. The
doping of KTP crystals with hafnium results in an elongation of K-O bonds in the potassium polyhedra and, as a consequence,
in a considerable (by approximately 180°C) decrease in the temperature of ferroelectric phase transition. The magnitude of
anomalous permittivity substantially decreases. The electrical conduction in the specimens studied decreases by approximately
half an order of magnitude in the low-temperature region but remains almost unchanged in the high-temperature region. Even
at minor concentrations, the presence of a hafnium additive in the specimens considerably (by 35%) enhances the intensity
of the second harmonic generation of laser radiation. 相似文献
120.
N. N. Novikova M. V. Kovalchuk S. N. Yakunin N. D. Stepina A. V. Rogachev E. A. Yurieva I. V. Marchenko T. V. Bukreeva N. N. Kolobylina A. L. Vasiliev 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2017,11(4):685-693
X-ray studies of dipalmitoylphosphatidylcholine (DPPC) single layers on the surface of a liquid provide detailed information on the interaction of metal particles with a single layer upon an increase in the surface pressure up to the collapse. Two complementary X-ray methods are used: grazing incidence diffraction and the X-ray standing waves method. The experimental results obtained for a single layer formed on a colloidal solution of magnetite nanoparticles reveal that the increase in the surface pressure is accompanied by an increase in the concentration of nanoparticles near the surface. In a series of experiments where metal particles of submicron size are sputtered onto a DPPC single layer, a sharp decrease in the intensity of the fluorescence yield from metal atoms is observed while the single layer is compressed. These data suggest that metal particles deposited onto the surface of a single layer were extruded into the aqueous subphase. 相似文献