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331.
We present a combined experimental (angle resolved photoemission: ARUPS) and theoretical study of the Shockley-type surface state in the L-gap of the (1 1 1)-face of Au covered with one monolayer of Ar. As known also from other systems consisting of rare-gas monolayers on noble metal (1 1 1) surfaces, the adsorbed rare-gas shifts the Shockley-state towards the Fermi level and increases the spin-orbit splitting, whereas the effective band mass remains unchanged. We analyze the observed changes by a comparison with ab initio slab-layer calculations based on the density functional theory (DFT), both within the local density approximation (LDA) and the generalized gradient approximation (GGA). Although the attractive van der Waals interaction between rare-gas and substrate is not properly considered in DFT there are considerable hybridization effects which allow to describe such weakly bound adsorbates quantitatively. We show to what extent the various DFT calculations correspond to the experimental results. Furthermore, we discuss the importance of lattice relaxation and the exact absorption position into the calculations. 相似文献
332.
N. M. Agababyan V. V. Ammosov N. Grigoryan H. Gulkanyan A. A. Ivanilov Zh. Karamyan V. A. Korotkov 《Physics of Atomic Nuclei》2011,74(2):221-228
The production of charged ρ mesons on nuclei and nucleons is investigated in charged current neutrino interactions at moderate energies (〈E 〉 ≈ 10 GeV), using the data obtained with SKAT bubble chamber. No strong nuclear effects are observed in ρ + and ρ ? production. The fractions of charged and neutral pions originating from ρ decays are obtained and compared with higher-energy data. From analysis of the obtained and available data on ρ + and K*+(892) neutrino production, the strangeness suppression factor is extracted: λ s = 0.18 ± 0.03. Estimation is obtained for cross section of coherent ρ + neutrino production on nuclei. 相似文献
333.
N. M. Agababyan V. V. Ammosov N. Grigoryan H. Gulkanyan A. A. Ivanilov Zh. Karamyan V. A. Korotkov 《Physics of Atomic Nuclei》2011,74(2):239-245
The charged current neutrino production of φ and D s + mesons is studied, using the data obtained with the SKAT bubble chamber exposed to the Serpukhov accelerator neutrino beam. It is found that the φ production occurs predominantly in the forward hemisphere of the hadronic c.m.s. (at x F > 0, x F being the Feynman variable), with the mean yield strongly exceeding the expected yield of directly produced φ mesons and varying from 〈n φ(x F s 0)〉 = (0.92 ± 0.34) × 10?2 at W > 2 GeV up to (1.23 ± 0.53) × 10?2 at W > 2.6 GeV and (1.44 ± 0.69) × 10?2 at W > 2.9 GeV, W being the invariant mass of the hadronic system. For the first time, the inclusive yield of leading D s + mesons carrying more than z = 0.85 of the current c-quark energy is estimated: 〈n D s + (z > 0.85, W > 2.9 GeV)〉 = (6.64 ± 1.91) × 10?2. It is shown that the shape of measured φ meson differential spectrum on xF is reproduced by that expected from the D s + → φX decays. An indication was obtained that this expected spectrum underestimates the measured φ yield. 相似文献
334.
E. R. Arakelova A. M. Khachatryan K. E. Avjyan N. S. Aramyan V. A. Gevorkyan S. G. Grigoryan G. N. Mirzoyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2011,46(6):293-299
Using the technique of DC-magnetron sputtering of zinc target in the temperature range from −30°C to 30°C, we have obtained
high-ohmic ZnO films (1.1×109, 2×1011, 1.3×106, and 108 Ω cm) on the substrates of glass, Si, and composites based on poly(3, 4-etylendioxythiophene) doped with polystyrensulfonic
acid (PEDOT-PSS), and flexible composites of PEDOT-PSS in polymer matrix of polyvinyl alcohol (PVA). Structural, optical,
and electrophysical characteristics of ZnO films prepared on different substrates were studied. Films obtained in certain
technological regime are on all substrates oriented along crystallographic direction (002) and have transmission coefficient
of the order 80–90% in the range 400–1000 nm. The developed technology for fabrication of high-ohmic grain-oriented ZnO films
at low substrate temperatures can be applied to creation of functional elements in acousto- and bioelectronics. 相似文献
335.
In this paper we construct a compact quantum semigroup structure on a Toeplitz algebra. We prove the existence of a subalgebra
in the dual algebra isomorphic to the algebra of regular Borel measures on a circle with the convolution product. We also
prove the existence of Haar functionals in the dual algebra and in the mentioned subalgebra. We show that this compact quantum
semigroup contains a dense subalgebra with the structure of a weak Hopf algebra. 相似文献
336.
Siberian Mathematical Journal - We prove that there exists a universal Haar series of the form $ \sum\nolimits_{k=0}^{\infty}a_{k}h_{k}(x) $ with $ a_{k}\searrow 0 $ such that, for all $... 相似文献
337.
A multicomponent system of complex refractory oxides of the composition Zn2 − x
(Zr
a
Sn
b
)1 − x
Fe2x
O4 (a + b = 1; a: b = 1: 5, 1: 4, 1: 3, 1: 2, 1: 1, 2: 1, 3: 1, 4: 1; x = 0−1.0; Δx = 0.05) was studied by X-ray diffraction. The samples were prepared from oxides of appropriate metals by low-temperature
plasma synthesis (hydrogen-oxygen flame). Two phases with wide homogeneity ranges were identified: α phase crystallized in
the crystal system of inverse cubic spinel and β phase with the structure of tetragonal spinel. The phase boundaries were
found. Structural data are presented for about 100 solid solutions. 相似文献
338.
An asymptotic method for calculating the collision-induced frequency and timing shifts for quasi-linear pulses in return-to-zero, wavelength-division multiplexed systems with predispersion and postdispersion compensation is developed. Predictions of the asymptotic theory agree well with quadrature and direct numerical simulations. Using this theory, computational savings of many orders of magnitude can be realized over direct numerical simulations. 相似文献
339.
S.S. Grigoryan 《Journal of Applied Mathematics and Mechanics》2009,73(6):747-753
A quantitative model describing the process of turbulent diffusion of the liquid mass of a chemical spill as it moves with the river current is constructed. The model contains a representation of the tensor components of the turbulent diffusion coefficients in terms of the initial parameters of the problem – the breadth and depth of the water flow in the river and the average flow velocity. According to the model proposed, the process consists of three stages: the initial, rapid stage, in which, owing to turbulent diffusion along the vertical coordinate, the pollutant concentration distribution evens out along this coordinate; the intermediate stage, in which, because of turbulent diffusion along the horizontal coordinates, the concentrations are likewise evened out along the horizontal coordinate transverse to the river channel; and the third, longest and slowest stage, in which quasi-one-dimensional turbulent diffusion occurs along the longitudinal (channel) coordinate, describing the “spreading” of the chemical slick (volume) carried downstream. Simple explicit formulae are obtained for a quantitative estimation of the characteristic pollutant concentrations at the end of the first and second stages and their “attenuation” with increasing distance as the chemical slick drifts with the current, and also the increasing longitudinal dimension of the slick with distance downstream. 相似文献
340.
A. O. Aboyan P. A. Bezirganyan S. E. Bezirganyan A. M. Grigoryan A. S. Tumasyan 《Crystal Research and Technology》1990,25(12):1405-1418
The diffraction of X-rays has been studied in two-crystal interferometers, the crystals of which had equal interplanar distances and between the blocks of which a non-diffracting zone was formed as a result of ion implantation. Also the X-ray diffraction was studied in two-crystal interferometers, the interplanar distances of which were different and the non-diffracting zone between the crystals had zero width. It was shown in plane wave approximation that the Moiré patterns should not be formed in case of former interferometers and necessarily arose with the latter type interferometers. 相似文献