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111.
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
112.
T. M. Usacheva V. I. Zhuravlev N. V. Lifanova V. K. Matveev 《Journal of Structural Chemistry》2011,52(6):1153-1160
The dielectric relaxation spectra (DRS) of 1,2-ethanediol, 1,2-propanediol, and 1,2,6-gexanetriol are analyzed in terms of
the Dissado-Hill (DH) model in a wide range of temperatures, with all parameters required for calculating the cluster dipole
moments being determined within the DH molecular model itself. The dependence of the equilibrium and relaxation properties
of DRS on the hydrocarbon radical length and the number of OH groups is studied. The dipole moments of the clusters are calculated.
It is shown how the roles of the processes of intracluster rearrangement are redistributed due to the break of hydrogen bonds
and fluctuation processes of synchronous exchange of molecules between the clusters. 相似文献
113.
O. Ya. Uryupina V. V. Vysotskii V. V. Matveev A. V. Gusel’nikova V. I. Roldughin 《Colloid Journal》2011,73(4):551-556
It is shown that gold nanoparticles can be produced using cellulose ethers, methylhydroxyethyl cellulose, and carboxymethyl cellulose as reducing agents that also play the role of nanoparticle stabilizers. Depending on the synthesis conditions, nanoparticle sizes vary in the range of 20–100 nm. The application of carboxymethyl cellulose as a stabilizer may give rise to the formation of a bimodal ensemble of nanoparticles with sizes of 4–5 and 30–40 nm. The differences in the mechanisms for the reduction and stabilization of gold nanoparticles in the presence of these cellulose derivatives are established by IR spectroscopy. The obtained colloidal dispersions of gold nanoparticles remain stable for a long time. 相似文献
114.
We use the equations of nonlinear theory of shallow shells to solve the problem of stability of thin elastic isotropic cylindrical
shells, with small initial shape imperfections, that are under the action of external uniform pressure. The problem solution
is constructed by the Rayleigh-Ritz method with the approximation of the shell midsurface displacement by double functional
sums in trigonometric and beam functions. The system of nonlinear algebraic equations is solved by using the methods of continuation
with respect to a close-to-best parameter. For the initial imperfections of the shells, we use their normalized deflections
from the limit points of overcritical branches of the loading trajectories. We consider various cases of the shell fixation
and support under loading by lateral and hydrostatic uniform pressure. We also construct the range of values of the critical
pressure, which, with the maximal deviation of the shell shape from the cylindrical shape up to 30%, covers practically all
known experimental data. 相似文献
115.
116.
The equivalence of the Kadomtsev-Petviashvili and Johnson equations is established in the class of rapidly decreasing Cauchy data. As an illustration of the isomorphism cited the Hamiltonian structure of the Johnson equation is studied.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 150, pp. 70–75, 1986.We thank M. A. Sall' for helpful discussions. 相似文献
117.
V. S. Matveev 《Mathematical Notes》1996,64(3):357-363
We construct a set of examples of bottom reliefs for which there exist captured waves corresponding to quasimodes of the wave operator ?D(x, y)?. 相似文献
118.
B. L. Korsounskii V. G. Matveev L. D. Nazina G. M. Nazin 《Russian Chemical Bulletin》1998,47(2):253-258
The primary stage of the decomposition of compounds RN(NO2)CH2C(NO2)2X is the homolytic cleavage of the C?NO2 bond, at X=NO2 and N?NO2 bond at X=F. The inductive effect of substituents decreases the dissociation energies of the C?N and N?N bonds by 1–2 kcal mol?1. Kinetic effects caused by the spatial interaction of groups and by stepwise decomposition of polyfunctional compounds are described. 相似文献
119.
V. N. Oraevsky G. E. Kocharov S. I. Boldyrev P. B. Dmitriev V. N. Ishkov V. P. Lazutkov G. A. Matveev Yu. N. Nitsora M. I. Savchenko D. V. Skorodumov Yu. E. Charikov 《Radiophysics and Quantum Electronics》1996,39(11-12):1015-1018
The first brief report on the results obtained in the IRIS experiment is presented. The IRIS instrument is an X-ray spectrometer based on proportional and scintillation counters designed for the measurement of solar X-ray radiation in the 2–200 keV range. Data on the 12 flares observed in March and April 1994 are reported, and examples of the flare radiation spectra are given. 相似文献
120.
Processes of ionization of the fast (μHe)+ mesic atom in multiple collisions with a diatomic molecule are examined. It is demonstrated that a consideration of molecule
alignment can significantly increase the probability of mesic atom ionization.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 30–33, May, 2005. 相似文献