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51.
We apply a topological approach to the investigation of quasilinear parabolic boundary-value problems. The class of problems under investigation is reduced to an operator equation with an operator satisfying condition (S)+. We establish theorems on solvability and give an example of the application of the approach indicated to the case of second-order parabolic equations. 相似文献
52.
P. A. Stabnikov S. I. Dorovskikh N. V. Pervukhina L. G. Bulusheva G. V. Romanenko 《Journal of Structural Chemistry》2014,55(3):488-492
Two bis-chelates M(tmih)2 (M = Cu(II), Ni(II), tmih = (CH3)3C(NCH3)CHCOC(CH3)3)? are synthesized and their crystal structures are determined using XRD (Bruker APEX-II diffractometer with a CCD detector, λMoK α, λCuK α, graphite monochromator, T = 240(2) K and 296(2) K): Cu(tmih)2 (I) (space group P21/c, a = 12.9670(8) Å, b = 18.4921(9) Å, c = 11.0422(6) Å, β = 93.408(4)°, V = 2643.1(3) Å3, Z = 4) and Ni(tmih)2 (II) (space group P21/c, a = 12.810(2) Å, b = 18.529(2) Å, c = 11.243(2) Å, β = 91.959(7)°, V = 2667.1(6) Å3, Z = 4). The complexes are isostructural; the coordination polyhedron of metal atoms is a flattened tetrahedron formed from two O atoms (Cu-O of 1.901(2) Å, 1.892(2) Å, Ni-O of 1.845(2) Å, 1.833(2) Å) and two N atoms (Cu-N of 1.976(3) Å, 1.972(3) Å, Ni-N of 1.911(2) Å, 1.920(2) Å) of the ligand; the chelate OMN angles (M = Cu(II), Ni(II)) are in the 87.4–93.1° range; the OMO and NMN angles are 162.2° and 167.2° in I, 171.1° and 173.2° in II. The complexes have the molecular structures formed from isolated molecules bonded by van der Waals interactions. Using a quantum chemical hybrid M06 method, the structures of copper(II) chelates with the H, CH3, CH2CH3, CH(CH3)2, and C(CH3)3 substituents at the nitrogen atom are calculated. Found that with a bulky substituent at the nitrogen atom, the formation of chelates is hindered due to the intraligand repulsion between the atoms of this substituent and the tert-butyl group. 相似文献
53.
Peter B. Kraikivskii Vitaly V. Saraev Galina V. Romanenko Dmitrii A. Matveev 《Journal of organometallic chemistry》2011,696(22):3483-3490
It has been shown that the reaction of Ni(allyl)2 with (2,6-diisopropylphenyl)diazabutadiene gives the imino-amide Ni complex (1). The imino-amide moiety of this complex undergoes some complicated rearrangements resulting in spontaneous formation of a paramagnetic π-allyl Ni(I) complex. Nickel complexes formed in the system have been studied with ESR, FTIR, 2D NMR, and mass spectrometry. The structure of complex 1 was studied with X-ray diffraction. 相似文献
54.
S. V. Fokin V. I. Ovcharenko G. V. Romanenko E. V. Tretyakov A. S. Bogomyakov L. V. Saloutina T. I. Filyakova V. I. Saloutin V. N. Charushin O. N. Chupakhin 《Russian Chemical Bulletin》2011,60(5):816-823
The first heterospin compounds based on bis(1,1,1,3,5,5,5-heptafluoro-4-iminopent-2-ene-2-aminato)copper(ii) (CuL2) and nitronyl nitroxide radicals, 2-R-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyls (NIT-R, where R = H, Me, Ph, and 1-methylpyrazol-4-yl), were synthesized and structurally characterized.
An important peculiarity of the structure of synthesized solid phases is the formation of a supramolecular structure due to
hydrogen bonds between the oxygen atoms of the nitronyl nitroxide fragments of NIT-R and the hydrogen atoms of the NH groups
of CuL2. 相似文献
55.
Romanenko K. V. Fraissard J. J. B. Espinose Lapina O.B. Reshetenko T. 《光散射学报》2005,17(3):281-282
pacc:6116N,8100Thetasksofnanocarbonmorphologyand porositycharacterizationarealwaysactually.So farthetextureandmicrostructureofcarbonswere examinedonlybysuitableadsorptionmethods,whicharenotalwayseffective.The129XeNMR onadsorbedxenonwasfirstintroducedandde… 相似文献
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58.
A. V. Khomchenko A. B. Sotsky A. A. Romanenko E. V. Glazunov A. V. Shulga 《Technical Physics》2005,50(6):771-779
A waveguide technique for measuring the absorption coefficient, refractive index, and thickness of thin films is suggested.
It is based on taking the angular dependence of the light beam reflection coefficient in an optical scheme involving a prism
coupler. Application of the technique to determining the parameters of thin-film waveguides, insulating coatings, and metal
films is considered. 相似文献
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