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1.
JETP Letters - The mechanical characteristics of diamond-like films, such as Dn21.8, Dn27.8, and Dn29.4 moiré diamanes, formed by the hydrogenation of graphene layers twisted at an angle of... 相似文献
2.
T. I. Mikhailova B. Erdemchimeg G. Kaminski A. G. Artyukh M. Colonna M. Di Toro I. N. Mikhailov Yu. M. Sereda H. H. Wolter 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(6):852-857
The asymmetry of velocity distributions of projectile-like fragments produced in heavy ion collisions is considered. The calculations
performed in the transport model approach (Vlasov kinetic equation with the collision term) are compared with the experimental
data for the 22Ne (40MeV/nucleon) + 9Be and 18O (35 MeV/nucleon) + 9Be(181Ta) reactions. It is found that the velocity distributions contain two components: a direct component centered at the beam
velocity and a dissipative component at lower energies, leading to asymmetry of velocity distributions. The direct component
is interpreted empirically within the Goldhaber model, and the centroids and widths σ0 of the distributions for each fragment are extracted. It is found that value of σ0 derived from experimental data is smaller by a factor of 2 than the theoretical one. The dissipative (also called deep inelastic)
component is described well by the transport calculations. It is shown that the ratio of yields of direct and dissipative
components, which determines the asymmetry of velocity distributions, depends on shape of the deflection function.
Original Russian Text ? T.I. Mikhailova, B. Erdemchimeg, G. Kaminski, A.G. Artyukh, M. Colonna, M. Di Toro, I.N. Mikhailov,
Yu.M. Sereda, H.H. Wolter, 2009, published in Izvestiya Rossiiskoi Akademii Nauk. Seriya Fizicheskaya, 2009, Vol. 73, No.
6, pp. 898–903. 相似文献
3.
Different technological approaches for creating graphene quantum dots by the adsorption of hydrogen atoms are considered.
The adsorption can occur both at convex portions of a distorted graphene nanoribbon and in the structure formed by two distorted
graphene nanoribbon rows superimposed on each other at the places free from the ribbon crossings. It is shown that settlement
of hydrogen atoms at convex portions of the nanoribbons is energetically favorable. This gives rise to the creation of insulating
graphane (CH) nanodomains separating the conducting regions. As a result, a graphene quantum dot appears. The variation of
the electron spectra of graphene quantum dots with the length of these graphane regions is discussed. 相似文献
4.
Carbon nanotubes coated with close-packed C60 (or C70) fullerenes, which are “attached” to the nanotubes by van der Waals forces, are considered and classified as a new class of nanocomposites. Semiempirical and molecular-dynamics calculations reveal the most energetically stable systems and show that a topological (Stone-Wales) defect on a nanotube can promote a more favorable “attachment” of fullerene to the nanotube. It has been shown that the molecular interaction of the fullerene coating with the nanotube leads to a significant change in its electronic spectrum, namely, to the formation of minibands including a large number of branches associated with the lift of the degeneracy of levels of C60 and to the consolidation of branches of the carbon nanotube into the Brillouin zone smaller than that in the carbon nanotube. This fact should strongly change the interaction of light with such a nanocomposite as compared to carbon nanotubes and fullerenes, which provides prospect of its application in photovoltaics. 相似文献
5.
N. P. Samchenko I. S. Alcheev T. Yu. Suva Yu. N. Artyukh N. V. Turutina V. G. Il'in 《Theoretical and Experimental Chemistry》1989,25(2):222-225
Using the method of thermal desorption of ammonia, we have studied the acidity of hydrogen forms of a number of zeolites: type Y, ultrahigh silica TsVK, synthetic and natural mordenite (M). The hydrogen forms of the TsVK and M zeolites have similar acidity spectra. But for HTsVK, the overall concentration of acidic centers is sufficiently lower than for HM, including weak centers (2.5–3 times) and strong centers (1.5 times). The concentration and strength distribution of acidic centers are very close in samples of synthetic and natural mordenite.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 244–247, March–April, 1989. 相似文献
6.
Yu. N. Artyukh N. K. Lunev O. P. Verkhgradskii G. A. Zelenkov L. A. Roeva E. A. Klimovich 《Theoretical and Experimental Chemistry》1991,26(4):476-479
The effect of additions of certain alcohols (methanol, ethanol, 2-propanol, and 2-butanol) to the synthesis gas on the distribution of the products during the hydrogenation of CO to alcohols at zinc-chromium oxide catalysts, promoted by various amounts of K2O, was studied. The results demonstrate the fundamental applicability of the principal theories of chain growth proposed by other authors for copper-containing catalysts. However, it was shown that the probability of -addition is lower while that of -addition is higher at the zinc-chromium-potassium catalysts than at copper-containing catalysts, and the calculated amounts of isobutanol obtained from the data for ethanol and propanols do not agree with the experimental data. It was found that there is an isomeric transition from the secondary alcohols (2-propanol, 2-butanol) to the primary alcohols at the surface of the catalyst, and this can evidently change the normal course of chain growth in the alcohols. It can be concluded that the activity of the alcohol added to synthesis gas in reaction with other C-fragments present on the surface of the catalyst increases with increase in the number of carbon atoms in the alcohol.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 26, No. 4, pp. 501–505, July–August, 1990. 相似文献
7.
8.
A new class of carbon nanostructures is considered: covalently (or molecularly) bound graphene and carbon nanotube fragments. As found using semiempirical computations and molecular dynamics methods, the structures formed by bonding nanotube edge atoms to a planar segment of a graphene nanofragment or its edge atoms to nanotube atoms arranged at the element of cylinder and graphene nanoribbons attached to a nanotube by van der Waals forces along the nanotube are the most energetically stable systems. 相似文献
9.
T. I. Mikhailova B. Erdemchimeg A. G. Artyukh G. Kaminski Yu. M. Sereda M. Colonna M. Di Toro H. H. Wolter 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(11):1511-1516
Peripheral heavy ion reactions are of interest for the production of new isotopes. In this contribution we present an investigation
of reactions of light projectiles O and Ne on Be and Ta targets at Fermi energies in the framework of transport theory. Transport
theory describes dissipative (deep-inelastic) processes, where considerable amounts of mass and energy are exchanged. The
data, on the other hand, also seem to include a more direct component with small energy loss. We separate the two components
on the basis of the velocity distribution and compare the dissipative component to the transport calculations. The primary
fragments of the transport calculation still have considerable excitation energies. For the comparison with experiment we
take into account the secondary evaporation in a statistical model. This improves the qualitative agreement with the data. 相似文献
10.
I. V. Voloshina V. L. Struzhko G. V. Filonenko Yu. N. Artyukh 《Theoretical and Experimental Chemistry》1987,22(6):720-723
The method of programmed thermal desorption of ammonia has been used to establish that on the surface of the sodium form of type TsVM zeolite having a modulus SiO2/Al2O3= 34.5 there are two types of acidic centers having ammonia desorption activation energies Ed equal to 40–45 and 80–100 kJ/mole. Replacement of Na+ by H+ leads to the appearance of a third type of center with a value ED=130–150 kJ/mole. In this case in the IR spectra of specimens saturated with ammonia a band appears at 1410 cm–1, which is evidence for the presence of NH
4
+
ions. Increasing the degree of Na+ replacement by H+ leads to a nonproportional rapid increase in the concentration of highly energetic centers, which may be explained by the partial transfer of aluminum into cationic positions with the formation of additional acidic centers.Translated from Teoreticheskie i Éksperimental'naya Khimiya, Vol. 22, No. 6, pp. 752–755, November–December, 1986. 相似文献