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71.
E. V. Lomakin 《Mechanics of Solids》2008,43(3):502-511
We analyze the results of experimental studies of effective strain properties of damaged, porous, and other inhomogeneous materials and study the main laws of their behavior under strain. We consider the possible versions of constitutive relations taking account of the dependence of the properties of the media under study on the loading conditions or the strain conditions and the relations between the shear and bulk strains. Since the traditional statement of the torsion problems for bodies with such properties cannot be used, we analyze the strain consistency equations and the relations between the strains and displacements in cylindrical coordinates and obtain expressions for the displacements in an appropriate generalized form, which can be used not only for the torsion problems. We study how the distributions of displacements, strains, and stresses under torsion depend on the parameter characterizing the susceptibility of the material strain properties to variations in the stress state type. We show that, in the case of torsion of a cylinder of circular cross-section, there is no deplanation of the cross-section, just as in the classical solution, but the distributions of displacements, strains, and stresses significantly differ from the well-known solutions. 相似文献
72.
Ivanets Andrei Milyutin Vitaliy Shashkova Irina Kitikova Natalja Nekrasova Natalya Radkevich Artsiom 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(3):1115-1123
Journal of Radioanalytical and Nuclear Chemistry - In this paper, we studied the features of stable and radioactive Cs(I), Sr(II) and Co(II) ions sorption on Ti–Ca–Mg phosphates. The... 相似文献
73.
Yanilkin Vitaliy V. Fazleeva Rezeda R. Nasretdinova Gulnaz R. Osin Yury N. Gubaidullin Aidar T. Ziganshina Аlbina Yu 《Journal of Solid State Electrochemistry》2020,24(4):829-842
Journal of Solid State Electrochemistry - Efficient two-step electrosynthesis of xCoO–yCo(OH)2 (CoOxHy)-supported silver nanoparticles (AgNPs) is carried out in N,N-dimethylformamide (DMF)... 相似文献
74.
N. N. Kolchigin V. M. Lomakin S. N. Pivnenko 《International Journal of Infrared and Millimeter Waves》1997,18(10):2019-2030
A two-dimensional problem of scattering of pulsed beams having arbitrary time and spatial form on a plane surface of a lossy
dielectric halfspace is solved. A pulsed beam has been modeled by letting an E- or H-polarized plane pulse with homogeneous
front pass through a space filter. The reflected pulse is found using an expansion of the incident pulsed beam over time-harmonic
plane waves. 相似文献
75.
Grigoriy A. Mun Vitaliy V. Khutoryanskiy Zauresh S. Nurkeeva Perizat I. Urkimbaeva Daulet Zhunuspaev 《Journal of Polymer Science.Polymer Physics》2004,42(14):2625-2632
Amphiphilic random copolymers based on vinyl ether of ethylene glycol and vinyl butyl ether as well as their polycomplexes with poly(acrylic acid) were studied as polymeric reagents for the stabilization of water/n‐hexane emulsions. The emulsion stability strongly depended on the content of vinyl butyl ether in the copolymers as well as their concentration in solution. The more hydrophobic copolymers stabilized emulsions more efficiently. An increase in the temperature and the addition of inorganic salts reduced the emulsion lifetime. The formation of interpolymer complexes between the copolymers and poly(acrylic acid) significantly influenced the stability of the emulsions. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2625–2632, 2004 相似文献
76.
Julia I. Nelina-Nemtseva Anna V. Gulevskaya Vitaliy V. Suslonov Alexander D. Misharev 《Tetrahedron》2018,74(10):1101-1109
π-Deficient ethynyl hetarenes were used as dipolarophiles in a 1,3-dipolar cycloaddition reaction with azomethine imines (2-arylidene-5-oxopyrazolidin-2-ium-1-ides). Both CuI-catalyzed and catalyst-free thermally induced reactions proceeded with high regioselectivity providing 6-hetaryl-5-aryl-2,3-dihydropyrazolo[1,2-a]pyrazol-1(5H)-ones in moderate to excellent yields. The ethynyl hetarenes (pyridines, pyrazines, quinoxalines, pteridines and pyrimido[4,5-c]pyridazines) with ortho-methyl, ortho-cyano and ortho-alkynyl substituents were applicable to this reaction. 1,3-Dipolar cycloaddition reactions of alkynyl hetarenes with azomethine imines or other 1,3-dipole reagents can be considered as an alternative synthetic approach to heterobiaryls. 相似文献
77.
78.
Bertrand MP Escoubet S Gastaldi S Timokhin VI 《Chemical communications (Cambridge, England)》2002,(3):216-217
Thiyl radical promotes the isomerisation of allylic amines into enamines via two consecutive hydrogen atom abstraction steps, and the subsequent polar addition of the corresponding thiol to the enamine results in the cleavage of the C-N bond via a thioaminal intermediate: this reaction provides a mild, metal-free methodology for the deprotection of allylated primary and secondary amines. 相似文献
79.
80.
S. M. Lomakin I. L. Dubnikova S. M. Berezina G. E. Zaikov 《Polymer Science Series A》2006,48(1):72-84
The specific features of thermal degradation and combustion of polypropylene nanocomposites based on organically modified layered aluminosilicate were studied. On the basis of thermogravimetric analysis data, a kinetic model that takes into account the diffusive character of the thermal degradation process for the PP nanocomposite was proposed. The basic flammability parameters of the nanocomposite were determined with the use of a cone calorimeter. The influence of diffusion constraints in the charred nanocomposite layer on the maximum heat release rate as a principal parameter of flammability was considered. 相似文献