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41.
42.
Shvets A. A. Borodkin S. A. Kogan V. A. Safaryan G. P. Safoklov B. B. Tkachev V. V. Filipenko O. S. 《Russian Journal of Coordination Chemistry》2003,29(1):28-32
The structure of the Cu[(2-O–)(5-NO2)C6H3N–CH=CH–+PPh3]2 complex with the CuN2O2 coordination core of distorted square-planar geometry was established by X-ray diffraction analysis. The molecules in the crystal structure of the Cu[(2-O–)(5-NO2)C6H3N–CH=CH–+PPh3]2 · 2CHCl3 solvate are bound via hydrogen bonds of two types, namely, C(sp
2)–H···O and C(sp
3)–H···O. 相似文献
43.
A fundamentally new recognition method of bio-objects (e.g., cancer cells as the most important case of them) that escape the immune system supervision control is suggested. It is proposed to use a unified complex consisting of several molecular groups (e.g., antibodies or their fragments) bound with each other. Binding targets are localized on the surface of this bio-object. The choice of the targets is determined by antigen profiling being expressed on the surface of these bio-objects. The recognition efficiency appears to be notably higher than in a situation when molecular groups do not form a unified complex and act separately. 相似文献
44.
The real and imaginary parts of the refractive index of thin zinc phthalocyanine films have been measured by two different methods (spectral and ellipsometric). The results obtained have been used to calculate the absorption and scattering cross sections of spherical zinc phthalocyanine nanoparticles in water as functions of their size. 相似文献
45.
Caitlin E. Karver Eric S. Molina Erin T. Economos Jonathan C. Fuentes Socrates M. Kaitson Samuel Kogan 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):101-105
Electrophilic trisubstituted ethylenes, halogen ring-substituted methyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO2CH3 (where R is 3-Br-4-CH3O, 5-Br-2-CH3O, 2-F-5-CH3, 2-F-6-CH3, 4-F-3-CH3, 4-F-3-PhO, 2-F-5-I, 2-F-6-I, 2-F3C, 4-F3C) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and methyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C-NMR. All the ethylenes were copolymerized with styrene (M1) in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 2-F-5-CH3 (6.4) > 4-F-3-PhO (5.6) > 4-F3C (4.8) > 3-Br-4-CH3O (3.7) > 2-F-5-I (3.6) > 2-F3C (2.2) > 2-F-6-I (2.1) > 5-Br-2-CH3O (1.9) > 4-F-3-CH3 (1.8) > 2-F-6-CH3 (1.2). Relatively high T g of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200-500°C range with residue (2–21% wt), which then decomposed in the 500–800°C range. 相似文献
46.
E. A. Berdonosova N. V. Maletskaya E. V. Kogan K. A. Kovalenko S. N. Klyamkin D. N. Dybtsev V. P. Fedin 《Russian Chemical Bulletin》2013,62(1):157-162
Mesoporous chromium(iii) terephthalate MIL-101 was treated with aqueous solutions of sodium fluoride, chloride, and bromide. The properties of the resulting compounds to sorb nitrogen, hydrogen, and methane were studied. The methane sorption was shown to depend on the nature of the inserted halide ion. The treatment with a sodium chloride solution leads to an increase in the methane uptake by MIL-101. 相似文献
47.
L. D. Popov S. I. Levchenkov I. N. Shcherbakov V. V. Minin G. G. Aleksandrov E. A. Ugolkova V. V. Lukov V. A. Kogan 《Russian Journal of Coordination Chemistry》2013,39(12):849-856
4-Formyl-3-methyl-1-phenylpyrazol-5-one quinolin-2-yl-(H2L1) and benzothiazol-2-ylhydrazones (H2L2) were synthesized and studied. Quantum-chemical modeling of possible tautomers of the hydrazones was performed. Copper(II) complexes of the general formula [Cu(HL)(ROH)]Y (R = CH3, C2H5; Y=NO3, ClO4) were obtained and examined by IR and EPR spectroscopy, magnetochemistry, and X-ray diffraction. Additional coordination through the N atom of the pyrazole ring enables the complex molecules to form zigzag polymer chains linked by intermolecular hydrogen bonds. 相似文献
48.
49.
S. I. Levchenkov L. D. Popov I. N. Shcherbakov V. G. Vlasenko A. A. Tsaturyan S. S. Beloborodov A. M. Ionov V. A. Kogan 《Russian Journal of General Chemistry》2014,84(10):1970-1978
Binuclear complexes of copper(II) with 1′-phthalazinylhydrazones of substituted salicylic aldehydes have been prepared and studied. Antiferromagnetic exchange interaction between copper(II) ions has been revealed in all the complexes. Taking advantage of quantum-chemical simulation, we have investigated the influence of the complexes structural isomerism on the character of the exchange interaction between the paramagnetic centers. X-ray absorbance spectroscopy afforded the structural parameters of coordination spheres of copper(II) ions; it has been demonstrated that dimerization occurred via the nitrogen atoms of phthalazine fragments. 相似文献
50.
A. I. Uraev L. D. Popov S. I. Levchenkov I. N. Shcherbakov V. G. Vlasenko K. Yu. Suponitskii S. S. Beloborodov D. A. Garnovskii V. A. Kogan 《Russian Journal of Coordination Chemistry》2014,40(9):599-606
The copper(II) and nickel(II) complexes based on bis(azomethine), which is the condensation product of 1-phenyl-3-methyl-4-formyl-5-mercaptopyrazole with 1,3-diaminopropan-2-ol, are synthesized. Bis-azomethines can form both binuclear and mononuclear complexes in which the hydroxy group is not involved in coordination. The binuclear copper(II) complexes with the acetate and pyrazolate bridges exhibit an antiferromagnetic exchange, which strength is determined by the nature of the bridge (2J = ?154 and ?424 cm?1, respectively). The structure parameters of the coordination spheres of the complexes are determined by X-ray absorption spectroscopy. The structure of the CHCl3 solvate of the binuclear copper(II) complex with the pyrazolate bridge is solved by X-ray diffraction analysis (CIF file CCDC 964655). 相似文献