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61.
A. E. Aleksenskii V. Yu. Osipov A. Ya. Vul’ B. Ya. Ber A. B. Smirnov V. G. Melekhin G. J. Adriaenssens K. Iakoubovskii 《Physics of the Solid State》2001,43(1):145-150
Thin ultradisperse diamond (UDD) layers deposited from a water suspension are studied by optical and x-ray photoelectron spectroscopy (XPS). The effective band gap determined by the 104-cm?1 criterion for ozone-cleaned UDD is 3.5 eV. The broad structureless photoluminescence band (380–520 nm) is associated with radiative recombination through a system of continuously distributed energy levels in the band gap of diamond nanoclusters. The optical absorption of the material at 250–1000 nm originates from absorption on the disordered nanocluster surface containing threefold-coordinated carbon. The surface of UDD clusters subjected to acid cleaning contains nitrogen-oxygen complexes adsorbed in the form of NO 3 ? nitrate ions. Annealing in a hydrogen atmosphere results in desorption of the nitrate ions from the cluster surface. The evolution of the oxygen (O1s) and nitrogen (N1s) lines in the XPS spectra under annealing of a UDD layer is studied comprehensively. 相似文献
62.
A. V. Kukhto É. É. Kolesnik A. L. Gurskii E. V. Lutsenko K. A. Osipov V. N. Pavlosvskii Yu. V. Grazulyavichyus A. Nedelcheva I. K. Grabchev 《Journal of Applied Spectroscopy》2007,74(6):915-920
We have studied the effect of the intensity of the exciting radiation and the temperature on the emission properties of two
kinds of thin-film samples based on blends of two types of organic electroactive materials: polyfluorene + iridium triphenylpyridinate
and polyepoxypropylcarbazole + zero-th order PAMAM dendrimer with eosin. We have shown that an increase in the excitation
intensity leads to an increase in the intensity of the luminescence of the polymer matrices and the iridium complex up to
a power density of 300 kW/cm2, and the emission of the dendrimer is rapidly saturated and does not return to the initial value when the excitation level
decreases. Heating up to 170°C followed by cooling causes an increase in the intensity for all the components except the dendrimer.
The data obtained show that annealing is an important method for improving the emission efficiency of the proposed thin-film
structures, due to a change in the packing of the activator molecules in the polymer matrix leading to more efficient transfer
of the excitation energy. Molecules of the studied dendrimer are not stable when exposed to optical radiation and temperature.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 6, pp. 820–825, November–December, 2007. 相似文献
63.
64.
The combined effective low energy QCD Lagrangians of Nambu-Jona-Lasinio (NJL) and ’t Hooft are supplemented with eight-quark interactions. This work is a follow-up of recent findings, namely (i) the six quark flavour determinant ’t Hooft term destabilizes the NJL vacuum, (ii) the addition of a chiral invariant eight-fermion contact term renders the ground state of the theory globally stable; (iii) stability constrains the values of coupling constants of the model, meaning that even in the presence of eight-quark forces the system can be unstable in a certain parameter region. In the present work we study a phenomenological output of eight-quark interactions considering the mass spectra of pseudoscalar and scalar mesons. Mixing angles are obtained and their equivalence to the two angle approach is derived. We show that the masses of pseudoscalars are almost neutral to the eight-quark forces. The only marked effect of the second order in the SU(3) breaking is found in the η-η′ system. The scalars are more sensitive to the eight-quark interactions. A strong repulsion between the singlet and octet members is the reason for the obtained low mass of the σ state within the model considered. 相似文献
65.
V. F. Osipov 《Vestnik St. Petersburg University: Mathematics》2010,43(3):169-174
The interplay and synthesis of antithetic elements of cognitive activity of mathematicians is considered. The emphasis is
on basic antithetic elements such as logic and intuition, generality and individuality, synthesis and construction. Besides,
we perform a dialectical analysis of the appearance of new abstract concepts based directly on one’s sensory experience or
on abstract concepts that have already been used earlier in the solution of mathematical problems. All conclusions from Euclid
and Diophantus to problems of foundations in the present state of the art are illustrated by examples. 相似文献
66.
67.
O. S. Osipov 《Siberian Mathematical Journal》2009,50(6):1062-1069
We consider an improper integral corresponding to the series with a two-point sum range which was constructed by Kornilov
in the space of integrable functions. We verify that the sum range of the integral is equal to the set of all constant functions. 相似文献
68.
Osipov D. A. Smirnov I. V. Grinyaev K. V. Ditenberg I. A. Korchagin M. A. 《Russian Physics Journal》2021,63(9):1583-1589
Russian Physics Journal - Using precursors, prepared by a preliminary mechanical activation of the 3Ni–Al powder mixture in the energy-intensive ball mills with and without a subsequent... 相似文献
69.
Osipov D. A. Smirnov I. V. Grinyaev K. V. Korotaev A. D. Pinzhin Yu. P. Ditenberg I. A. Korchagin M. A. Esikov M. A. Mali V. I. 《Russian Physics Journal》2021,64(8):1460-1467
Russian Physics Journal - A comparative study of microstructure parameters and mechanical property characteristics of consolidated Ni3Al samples formed by spark plasma sintering after a preliminary... 相似文献
70.
The heat transfer taking place between the gas and the surface of the plate in the zone of three-dimensional separation of the turbulent boundary layer in front of a set of supersonic jets injected perpendicularly to a subsonic carrier flow is considered. The aim of this investigation is to establish the main physical characteristics of heat transfer in the separation zones in front of jet obstacles and to obtain the distributions of the local heat-transfer coefficients and the temperature of the thermally insulating wall as functions of the parameters of the carrier flow and the injected jets. Analysis of the experimental results yields certain approximating relationships for the distribution of the local heat-transfer coefficients as functions of the Mach number of the carrier flow M, the Mach number of the jet Mj, the relative boundary-layer displacement thickness s=
s
*
/d, and the degree of jet superheating TojTo relative to the separation zones in front of supersonic jet obstacles.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 68–72, July–August, 1975. 相似文献