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71.
72.
G. A. Ksendzova G. I. Polozov I. V. Skornyakov V. L. Sorokin G. B. Tolstorozhev O. I. Shadyro A. A. Yakunin 《Optics and Spectroscopy》2007,102(4):551-556
The intermolecular interactions in solutions of aminophenols in CCl4 are studied by the methods of IR Fourier spectroscopy. If the hydroxyl groups of aminophenol molecules occupy the ortho positions with respect to the amino groups of the molecules, the hydroxyl and amino groups are involved in intramolecular interactions with the formation of hydrogen bonds O-H...N and N-H...O. The introduction of two additional tert-butyl groups into the structure of the aminophenol molecule facilitates the formation of O-H...N bonds and impedes the formation of N-H...O bonds. The occurrence of the carbonyl group in the structure of aminophenols leads to the formation of intramolecular hydrogen bonds O-H...O=C. The introduction of the methyl groups into carbonyl-containing aminophenols transforms the O-H...O=C bond into the hydrogen bond N-H...O=C. 相似文献
73.
74.
The local and global nonlinear dynamics of a two-degree-of-freedom model system is studied. The undeflected model consists
of an inverted T formed by three rigid bars, with the tips of the two horizontal bars supported on springs. The springs exhibit an elasto-plastic
response, including the Bauschinger effect. The vertical rigid bar is subjected to a conservative (dead) or non-conservative
(follower) force having static and periodic components. First, the method of multiple scales is used for the analysis of the
local dynamics of the system with elastic springs. The attention is focused at modal interaction phenomena in weak excitation
at primary resonance and in hard sub-harmonic excitation. Three different asymptotic expansions are utilised to get a structural
response for typical ranges of excitation parameters. Numerical integration of the governing equations is then performed to
validate results of asymptotic analysis in each case. A full global nonlinear dynamics analysis of the elasto-plastic system
is performed to reveal the role of plastic deformations in the stability of this system. Static 'force-displacement' curves
are plotted and the role of plastic deformations in the destabilisation of the system is discussed. Large-amplitude non-linear
oscillations of the elasto-plastic system are studied, including the influence of material hardening and of static and sinusoidal
components of the applied force. A practical method is proposed for the study of a non-conservative elasto-plastic system
as a non-conservative elastic system with an 'equivalent' viscous damping.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
75.
76.
Turbulent isobaric vapor-air jet flows with homogeneous condensation are examined. A general system of equations, including the gas dynamic and kinetic equations, the thermodynamic relations and the equations for the turbulence model, is formulated. The moment kinetic equations valid for the free-molecular regime of drop growth in the surrounding medium are extended to other drop mass transfer regimes. The structure of the condensation shock, which includes the nucleation zone and the zone of drop growth on pre-existing nuclei, is investigated on the basis of a general asymptotic approach. Additional conditions at the nucleation and condensation shocks, the need for which follows from the requirement that the shocks be evolutionary, are obtained. Certain problems of averaging of the source terms in the moment equations are discussed, and with reference to the simple example of averaging of the frozen nucleation rate it is shown that the latter is nonzero for a mean supersaturation less than unity and that the condensation zone is displaced upstream. Condensation in a turbulent jet into which condensation-intensifying charged particles (corona discharge ions) are introduced is studied. A numerical method of analyzing homogeneous condensation in turbulent jets, which makes it possible to obtain the gas dynamic and disperse flow characteristics for various temperature conditions with allowance for the averaging of the source terms, is developed.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 43–52, March–April, 1988.The authors wish to thank V. R. Kuznetsov for discussing various aspects of their work. 相似文献
77.
Rebounding of a shaped-charge jet 总被引:1,自引:0,他引:1
E. V. Proskuryakov M. V. Sorokin V. M. Fomin 《Journal of Applied Mechanics and Technical Physics》2007,48(5):633-635
The phenomenon of rebounding of a shaped-charge jet from the armour surface with small angles between the jet axis and the
target surface is considered. Rebounding angles as a function of jet velocity are obtained in experiments for a copper shaped-charge
jet. An engineering calculation technique is developed. The results calculated with the use of this technique are in reasonable
agreement with experimental data.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 48, No. 5, pp. 17–20, September–October, 2007. 相似文献
78.
I. D. Sorokin V. I. Pergushov L. I. Savostina M. Ya. Melnikov 《High Energy Chemistry》2014,48(3):180-184
It has been established that transformations of azetidine radical cations observed in freonic matrices under the action of light with λ = 436 nm (T = 77 K) are associated with C-N bond cleavage which corresponds to the cyclic form yielding a mixture of open distonic C-centered radical cations of the following structure: ·CH2CH2CH=NH 2 + 相似文献
79.
Kockrick E Lescouet T Kudrik EV Sorokin AB Farrusseng D 《Chemical communications (Cambridge, England)》2011,47(5):1562-1564
Metal phthalocyanine complexes encapsulated in MIL-101, and used as "ship-in-a-bottle" catalysts, show outstanding TONs in the aerobic oxidation of tetralin. 相似文献
80.
V. N. Sorokin 《Proceedings of the Steklov Institute of Mathematics》2017,298(1):294-316
Multiple orthogonal polynomials for three discrete Meixner measures with identical exponential decay at infinity are studied. These polynomials are the denominators of the type II Hermite–Padé approximants to some hypergeometric functions. The limit distribution of zeros of such polynomials scaled in a certain way is described in terms of equilibrium logarithmic potentials and in terms of algebraic curves. 相似文献