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51.
V. M. Lobanov 《Technical Physics》2005,50(11):1485-1489
The height of an extra low-energy maximum in the energy distribution of electrons tunneling from crystalline carbon fibers
and carbon nanotubes is studied as a function of emitter heating and emitter rotation relative to the energy analyzer axis.
The relationships found are related to emission from electron states on the surface of the reconstructed nanocrystals and
nanotubes. 相似文献
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N. V. Vostokov Yu. N. Drozdov Z. F. Krasil’nik D. N. Lobanov A. V. Novikov A. N. Yablonskii 《JETP Letters》2002,76(6):365-369
The photoluminescence spectra of structures with self-assembled GeSi/Si(001) islands are investigated as functions of the growth temperature. It is shown that the shift of the peak of photoluminescence from islands toward lower energies on decreasing the growth temperature is due to the suppression of Si diffusion into islands and an increase in the fraction of Ge in islands. A photoluminescence signal from the GeSi islands is found in the region of energies down to 0.6 eV, which is considerably smaller than the band-gap width in bulk Ge. The position of the peak of photoluminescence from islands is described well by the model of a real-space indirect optical transition with account of the real composition and elastic strains of the islands. Mono-and multilayer structures are obtained with self-assembled GeSi/Si(001) nanoislands exhibiting a photoluminescence signal in the region 1.3–2 μm at room temperature. 相似文献
54.
A study of the local structure of the turbulent gas-liquid bubble flow in a tube with an inner diameter of 20 mm was performed
by using the electrodiffusion method. A special feature of this research is the relatively small (up to 5% of the volume)
quantities of gas added to the flow. To determine the radial distribution of the liquid velocity, its pulsations, and the
local void fraction, we used a sensor of the blunt nose type, which simultaneously functioned as an electrochemical sensor
and a conductivity sensor. It was shown that adding even small quantities of gas into the flow leads to a change in the liquid
velocity profile in comparison with the single phase flow and rearrangement of the turbulent structure of the flow. 相似文献
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A. G. Yurchenko V. V. Lobanov T. V. Fedorenko V. A. Topchii A. G. Zhukov 《Theoretical and Experimental Chemistry》1989,25(3):331-334
The spatial and electronic structures of the adamantane molecule (AdH), the 1-adamantyl radical (1-Ad.), the 1-adamantyl cation (1-AD+), and the 1-adamantyl anion (1-Ad–) have been calculated by the SCF-MO-LCAO method in the all-valence-electron MINDO approximation. The calculated heats of formation attest to the fact that the homolytic cleavage of the C-H bond is energetically most advantageous in the gaseous phase or in nonpolar inert solvents. The formation of a 1-Ad–, H+ pair is associated with the largest expenditure of energy due to the large ionization potential of the hydrogen atom.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 3, pp. 357–360, May–June, 1989. 相似文献
58.
V. Ya. Zayats V. M. Pinchuk V. V. Lobanov 《Theoretical and Experimental Chemistry》1988,24(3):324-328
The distributions of the molecular electrostatic potential in the central cavities of the free bases protoporphyrin IX, mesoporphyrin IX, etioporphyrin III and of their mono- and dianions have been calculated. An analysis has been made of the influence of substituents in the pyrrole rings of the investigated porphyrins on the potential distribution in their central cavities and the possible mechanism for addition of protons to the appropriate dianions.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 24, No. 3, pp. 335–339, May–June, 1988. 相似文献
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