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101.
Simonov Yu. A. Gdaniec M. Filippova I. G. Baca S. G. Timco G. A. Gerbeleu N. V. 《Russian Journal of Coordination Chemistry》2001,27(5):353-359
A new coordination compound [Co(Pht)(2-MeIm)2] (I), where Pht2–is the deprotonated radical of o-phthalic acid (H2Pht) and 2-MeIm is 2-methylimidazole, was synthesized. Its structure was established using X-ray diffraction analysis. The crystal is orthorhombic: space group Pca21, a= 15.350(3), b= 7.957(2), c= 13.997(3) Å, (calcd.) = 1.505 g/cm3, and Z= 4. The tetrahedral coordination of the Co(II) atom includes two N atoms of two 2-methylimidazole molecules and two oxygen atoms of two carboxyl groups from different acid radicals. The Co–N distances are equal to 2.022(2) and 2.031(2) Å, while the Co–O distances are 1.972(2) and 2.000(2) Å. The carboxyl groups of the Pht2–radical and the aromatic nucleus form angles of 47.2° and 35.9°, whereas the angle formed by the carboxyl groups themselves is 50.3°. Compound Iis a polymer, which is confirmed by the 1,6-bridging function of the o-phthalic acid radical. The Co···Co distance in a chain is equal to 7.367 Å. Separate chains are united in the crystal into a framework via N–H···O hydrogen bonds. 相似文献
102.
S. V. Kotomin T. I. Barankova E. P. Plotnikova T. N. Filippova 《Polymer Science Series D》2016,9(3):335-340
Microplastics have been prepared by impregnating aramid and glass fibers with of polysulfone melts of various viscosities unfilled and filled with montmorillonite. A minimum of the melt viscosity has been found at a montmorillonite content of 1 wt %. Radial-transverse impregnation of multifilament fiber by a thermoplastic melt has been studied by the gravimetric method. Introduction into the polysulfone melt up to 1% of the filler at the initial stage of impregnation have almost no effect on the rate of the process; however, a decrease in it is observed as compared subsequently to impregnation with the melt containing no filler. It has been shown that torsional rigidity of microplastics, along with weight change, characterizes the degree of fiber impregnation. 相似文献
103.
104.
E. V. Filippova K. M. Polyakov T. V. Tikhonova T. N. Stekhanova K. M. Boiko V. O. Popov 《Crystallography Reports》2005,50(5):796-800
Formate dehydrogenase (FDG) from methylotrophic bacteria Pseudomonas sp. 101 catalyzes the reaction of oxidation of the formate ion to carbon dioxide, which is accompanied by the reduction of nicotinamid adenine dinucleotide (NAD+). The structures of the apo and holo (enzyme-NAD-azide triple complex) forms of the enzyme were determined earlier. In an attempt to prepare a complex of FDG with the product of the enzymatic reaction (NADH), a new crystal modification of FDG is obtained (space group P42212, a = b = 93.3 Å, c = 103.05 Å). The FDG structure is solved by the molecular replacement method and refined to R = 20.7%. The asymmetric part of the unit cell contains one FDG molecule. In contrast to the previously studied FDG structures, the biologically active dimer is formed by the crystallographic rotation axis. A comparative structural analysis of the studied form with the apo and holo forms of the enzyme is performed. The influence of the molecular structure on the environment in the crystal is investigated. 相似文献
105.
E. V. Filippova K. M. Polyakov T. V. Tikhonova T. N. Stekhanova K. M. Boiko I. G. Sadykhov V. I. Tishkov V. O. Popov N. Labru 《Crystallography Reports》2006,51(4):627-631
Formate dehydrogenase (FDH) from the methylotrophic bacterium Pseudomonas sp. 101 catalyzes oxidation of formate to NI2 with the coupled reduction of nicotinamide adenine dinucleotide (NAD+). The three-dimensional structures of the apo form (the free enzyme) and the holo form (the ternary FDH-NAD+-azide complex) of FDH have been established earlier. In the present study, the structures of FDH complexes with formate are solved at 2.19 and 2.28 Å resolution by the molecular replacement method and refined to the R factors of 22.3 and 20.5%, respectively. Both crystal structures contain four protein molecules per asymmetric unit. These molecules form two dimers identical to the dimer of the apo form of FDH. Two possible formatebinding sites are found in the active site of the FDH structure. In the complexes the sulfur atom of residue Cys354 exists in the oxidized state. 相似文献
106.
I. P. Lisovskii L. A. Smakhtin N. V. Filippova V. I. Volgin 《Journal of Radioanalytical and Nuclear Chemistry》1971,8(2):313-320
A semi-automatic pneumatic transport system for nuclear reactors is described. The sealed polyethylene capsules containing
the sample are placed into transport containers. Ten such containers are placed manually into a feeding device. All subsequent
operations (irradiation, removal of the capsule from the container, and transport of the capsule to the laboratory for activity
measurement) are automated. Total time from the completion of irradiation to the beginning of measurement is 10–20 sec. 相似文献
107.
M. M. Ulyashova G. V. Presnova Yu. I. Pobolelova A. A. Filippova A. M. Egorov M. Yu. Rubtsova 《Moscow University Chemistry Bulletin》2016,71(4):236-242
The method of hybridization analysis on microarrays with enzymatic detection based on horseradish peroxidase is applied to screen infectious agents of nosocomial and community-acquired infections for beta-lactamase genes causing resistance to beta-lactam antibiotics. The advantages of using this method for the rapid identification of genes are demonstrated. Similarities and differences in the distribution of beta-lactamase genes identified in the infectious agents of nosocomial and community-acquired infections are revealed. The most common type of extended-spectrum beta-lactamases (ESBLs) is CTX-M. The high prevalence of extended-spectrum beta-lactamases, particularly of the TEM-1 beta-lactamase, is demonstrated. Individually or in combination with genes of TEM-1 and SVH-1 beta-lactamases, the genes of subgroup CTX-M-1 beta-lactamases were the most frequently identified in community-acquired infectious agents. There were no cases of the simultaneous detection of multiple ESBLs in community-acquired infectious agents. Much more varied combinations of beta-lactamases were identified in nosocomial infectious agents: a combination of extended-spectrum beta-lactamases and broad-spectrum beta-lactamases was identified in 62% of strains and the simultaneous presence of two different types of ESBLs was identified in 18% of strains. 相似文献
108.
Olga Botezat Irina G. Filippova Jürg Hauser Karl Krämer Silvio Decurtins Shi-Xia Liu 《Journal of Coordination Chemistry》2016,69(1):72-80
A new μ3-oxo trinuclear chromium(III) propionate cluster, [Cr3(μ3-O)(O2CCH2CH3)6(pyr)3]NO3·0.25(H2O) (1), has been synthesized by reaction of a μ3-oxo trinuclear chromium(III) propionate precursor [Cr3(μ3-O)(O2CCH2CH3)6(H2O)3]NO3 with a pyrazol ligand (pyr) and characterized by IR spectroscopy, single-crystal X-ray structure determination, and thermal analysis. Magnetic susceptibility and magnetization studies revealed antiferromagnetic exchange interactions within the trinuclear Cr(III) cluster (J = ?11.9 cm?1) and determined the electronic ground state (S = ½) of the compound. 相似文献
109.
V. P. Filippova Yu. A. Perlovich O. A. Krymskaya 《Bulletin of the Russian Academy of Sciences: Physics》2016,80(10):1279-1286
An algorithm that employs the method of successive relaxation for determining the parameters of the pairwise interaction potential of iron and nonmetallic atoms that implicitly considers the redistribution of electron density between atoms is developed. The parameters of the interatomic interaction potential are calculated for ten pairs of elements: Fe–P, Fe–S, Fe–B, Fe–V, Fe–Mo, Fe–Cr, Fe–Mn, Fe–Si, Fe–Ni, and Fe–Al. The structural and thermodynamic properties of solid solutions based on iron and pure materials, and some pairwise interaction potentials constructed earlier in the Lennard–Jones form for identical metal atoms and homogeneous pairs of different metal–metal atoms, are used in these calculations. 相似文献
110.
A. A. Filippova A. A. Voronina A. S. Vashurin 《Russian Journal of Inorganic Chemistry》2017,62(6):777-782
Association of sulfonated derivatives of cobalt phthalocyaninate in solutions in the presence of nitrogen-containing organic ligands is studied. Ligand denticity and spatial structure are found to be the main factors controlling the association equilibrium between sulfonated metallophthalocyanines. 相似文献