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1.
I. Kolokolov V. Lebedev M. Stepanov 《Journal of Experimental and Theoretical Physics》1999,88(3):506-516
We consider advection of a passive scalar θ(t,r) by an incompressible large-scale turbulent flow. In the framework of the Kraichnan model all PDF’s (probability distribution
functions) for the single-point statistics of θ and for the passive scalar difference θ(r
1)−θ(r
2) (for separations r
1−r
2 lying in the convective interval) are found.
Zh. éksp. Teor. Fiz. 115, 920–939 (March 1999)
Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor. 相似文献
2.
The critical current J
c(θ) of an intergrain boundary is calculated as a function of the contact misorientation angle θ of the granules. It is assumed that the ordering parameter is suppressed in regions near boundaries with an enhanced mechanical
stress induced by randomly distributed surface dislocations. The stress distribution function is determined using a probabilistic
approach. Assuming that the weak coupling at the boundary is Josephson coupling, an analytic expression is found for the angular
dependence J
c(θ) (for tilt and twist boundaries). The magnitude of the residual critical current of a boundary in a strong magnetic field
is estimated.
Fiz. Tverd. Tela (St. Petersburg) 40, 393–402 (March 1998) 相似文献
3.
The excess 1/f noise in a random lattice with bond resistances r∼exp(−λx), where x is a random variable and λ≪1, is studied theoretically. It is shown that if the correlation function {δr
2}∼r
r
θ+2, then the relative spectral density of the noise in the system is expressed as C
e∼λm exp(−λ(1−p
c)), where p
c is the percolation threshold and m=νd (ν is the critical exponent of the correlation length and d is the dimensionality of the problem). It is hypothesized that the exponent m possesses a dual universality: It is independent of 1) the geometry of the lattice and 2) the θ-mechanism responsible for
the generation of the local noise. Numerical modeling in a three-dimensional lattice gives m=52.3 for θ=1 and θ=0, in agreement with the hypothesis.
Pis’ma Zh. éksp. Teor. Fiz. 63, No. 8, 614–618 (25 April 1996) 相似文献
4.
It has been shown by using the statistical approach that the angular dependence of intensity I(θ) in multiple small-angle light scattering can be described by Lévy’s universal distribution functions. The fundamental property
of the stability of these distributions permits one to extract information on the characteristics of fractal media as complete
as it is possible in the simple single-scattering case. In particular, an analysis of the polarization characteristics of
I(θ) in disordered PST reveals that the surface fractals observed in these crystals are of the heterophase rather than domain
origin.
Fiz. Tverd. Tela (St. Petersburg) 40, 1537–1541 (August 1998) 相似文献
5.
It is proposed that the suppression of transport in the H-mode in tokamaks is caused by the absence of trapped ions in the
transport barrier. If the poloidal Mach number M=v
θ
B/(v
TiBθ) is large there are exponentially few trapped ions. This criterion agrees with experimental observations of H-mode plasmas.
The recently observed transport suppression by reversed shear also points to the dominant role of trapped particles in turbulent
transport.
Pis’ma Zh. éksp. Teor. Fiz. 63, No. 6, 427–430 (25 March 1996)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
6.
A. V. Dvurechenskii V. A. Zinov’ev V. A. Markov 《Journal of Experimental and Theoretical Physics》1998,87(6):1116-1121
Reflected high-energy electron diffraction (RHEED) and detection of the intensity oscillations of the specular reflection
have been used to investigate morphological changes in Si(111) associated with the two-dimensional layer-by-layer mechanism
of silicon growth from a molecular beam under conditions of pulsed (0.25–1 s) bombardment with low-energy (80–150 eV) Kr ions
in the interval of small total radiative fluxes (1011–1012 cm22), for which the density of radiation-generated defects is small in comparison with the surface density of the atoms. After
pulsed ion bombardment an increase in the intensity of the specular reflection is observed if the degree of filling of the
monolayer satisfies 0.5<θ<1. No increase in the intensity occurs during the initial stages of filling of the monolayer. The maximum amplitude increment
of the oscillations is reached at θ≈0.8. The magnitude of the amplitude increment of the RHEED oscillations increases with temperature up to 400°C and then falls.
At temperatures above 500°C amplification of the reflection intensity essentially vanishes. Experiments on multiple ion bombardment
of each growing layer showed that the magnitude of the amplitude increment of the oscillations decreased as a function of
the number of deposited layers (the order of the RHEED oscillation). A mechanism for the observed phenomena is proposed, based
on the concept of surface reconstruction by pulsed ion bombardment accompanied by formation of a (7×7) superstructure, which
corresponds to a decrease of the activation energy of surface diffusion of the adatoms. Within the framework of the proposed
mechanism the results of Monte Carlo modeling agree with the main experimental data.
Zh. éksp. Teor. Fiz. 114, 2055–2064 (December 1998) 相似文献
7.
Lorenzo Bertini Davide Gabrielli Joel L. Lebowitz 《Journal of statistical physics》2005,121(5-6):843-885
We investigate a one-dimensional chain of 2N harmonic oscillators in which neighboring sites have their energies redistributed randomly. The sites −N and N are in contact with thermal reservoirs at different temperature τ− and τ+. Kipnis et al. (J. Statist. Phys., 27:65–74 (1982).) proved that this model satisfies Fourier’s law and that in the hydrodynamical scaling limit, when N → ∞, the stationary state has a linear energy density profile
, u ∈[−1,1]. We derive the large deviation function S(θ(u)) for the probability of finding, in the stationary state, a profile θ(u) different from
. The function S(θ) has striking similarities to, but also large differences from, the corresponding one of the symmetric exclusion process.
Like the latter it is nonlocal and satisfies a variational equation. Unlike the latter it is not convex and the Gaussian normal
fluctuations are enhanced rather than suppressed compared to the local equilibrium state. We also briefly discuss more general
models and find the features common in these two and other models whose S(θ) is known. 相似文献
8.
Sh. Makhkamov N. A. Tursunov M. Karimov S. Zainabidinov A. R. Sattiev M. N. Erdonov Kh. M. Kholmedov 《Russian Physics Journal》2010,53(5):499-503
Electric and structural methods are used to investigate formation of impurity-defective complexes in silicon doped with palladium.
It is demonstrated that acceptor levels E
C
– 0.18 and E
v
+ 0.34 eV detected in silicon during incorporation of palladium are caused by singly and doubly negatively charged states
of [Pd–V] complexes, and the donor level E
v
+ 0.32 eV is a product of chemical compound of palladium with hydrogen forming the [Pd–H] complex. It is assumed that the
palladium impurity in the doped silicon samples causes the elastic crystal energy to change and impurity clouds to be formed
around microdefects. An increase in the temperature of palladium diffusion in silicon causes the impurity clouds to decay
and the microdefect core sizes to decrease with their subsequent chaining into a needle. 相似文献
9.
P. A. Alekseev E. S. Klement’ev V. N. Lazukov I. P. Sadikov M. N. Khlopkin M. Adams A. Yu. Muzychka I. L. Sashin N. B. Kol’chugina O. D. Chistyakov 《JETP Letters》1996,63(12):1000-1006
The effects of the crystal field (CF) on the paramagnetic Pr ion in a number of compounds of the type R1−x
PrxNi (R = Ce, La, Y), in which a transition of the cerium ions from an intermediate-valence into a Kondo state occurs as La
is substituted for Ce, are investigated. The level schemes of the Pr ion in the CF are reconstructed from inelastic neutron
scattering spectra and the temperature dependence of the heat capacity in different magnetic fields (B=0–8 T). The parameters of the low-symmetry CF in the compounds RNi are determined from the experimental data. It is established
that in the Kondo regime the hybridization of the f electrons with conduction electrons only gives a proportional increase in all the parameters of the CF potential. At the
same time, partial delocalization of the f electrons in the intermediate-valence state results in charge redistribution, which is manifested in different scales for
the changes in the different CF parameters.
Pis’ma Zh. éksp. Teor. Fiz. 63, No. 12, 947–952 (25 June 1996) 相似文献
10.
We have measured the absorption cross sections of oxygen molecules in oxygen and in an oxygen-argon mixture heated by a shock
wave, in the wavelength range 190–250 nm at temperatures of 1500–7000 K, for thermal equilibrium conditions behind the shock
wave front. Analysis of the absorption cross sections obtained allowed us to select a data set that adequately describes the
absorption characteristics of the electronic transition X3Σ
g
−
→ B3Σ
u
−
for the oxygen molecule.
In order to approximate the temperature dependence of these cross sections at a temperature of 1500–4500 K, we chose the function
σ(λ, T) = σ0(λ)(1 − exp (−θ/T)) exp (− n*θ/T) where θ0 = 1.4·10−17, 1.4·10−17, 1.2·10− 17, and 1.3·10−17 cm2, n* = 3.1, 4.1, 5.6, and 7.47 for wavelengths 190, 210, 230, and 250 nm, respectively; θ = 2240 K is the characteristic temperature
of the O2 molecules. The approximation error was 19–25% and did not exceed the experimental error.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 1, pp. 13–17, January–February, 2006. 相似文献
11.
S. G. Ovchinnikov L. V. Burkova V. A. Seredkin V. Yu. Yakovchuk 《Physics of the Solid State》1999,41(1):80-86
A study is reported of the structural, magnetic, and magneto-optic properties of Mn/Dy/Bi films obtained by multilayer technology.
The maximum Kerr rotation angle in such films is shown to be θ
k
=2.25°. Possible reasons for such a large Kerr effect enhancement are considered, namely, an increase in the 6p–3d transition probability caused by symmetry distortion, polarization of the Bi6p band, and a change in the density of states near the Fermi level. The latter reason has been analyzed by simulating the electronic
structure of Mn/Dy/Bi through superposition of Dy levels on the MnBi band structure. This approach has revealed possible additional
transitions which may be induced by the presence of a Dy buffer and could contribute to the Kerr magneto-optic effect.
Fiz. Tverd. Tela (St. Petersburg) 41, 91–97 (January 1999) 相似文献
12.
Xuguang Lu 《Journal of statistical physics》2006,124(2-4):517-547
The paper considers macroscopic behavior of a Fermi–Dirac particle system. We prove the L
1-compactness of velocity averages of weak solutions of the Boltzmann equation for Fermi–Dirac particles in a periodic box with the collision kernel b(cos θ)|ρ−ρ
*|γ, which corresponds to very soft potentials: −5 < γ ≤ −3 with a weak angular cutoff: ∫0
π
b(cos θ)sin 3θ dθ < ∞. Our proof for the averaging compactness is based on the entropy inequality, Hausdorff–Young inequality, the L
∞-bounds of the solutions, and a specific property of the value-range of the exponent γ. Once such an averaging compactness is proven, the proof of the existence of weak solutions will be relatively easy. 相似文献
13.
I. L. Drichko I. Yu. Smirnov A. V. Suslov O. A. Mironov D. R. Leadley 《Journal of Experimental and Theoretical Physics》2010,111(3):495-502
Magnetoresistivity ρ
xx
and ρ
xy
and the acoustoelectronic effects are measured in p-Si/SiGe/Si with an impurity concentration p = 1.99 × 1011 cm−2 in the temperature range 0.3–2.0 K and an tilted magnetic field up to 18 T. The dependence of the effective g factor on the angle of magnetic field tilt θ to the normal to the plane of a two-dimensional p-Si/SiGe/Si channel is determined. A first-order ferromagnet-paramagnet phase transition is observed in the magnetic fields
corresponding to a filling factor ν = 2 at θ ≈ 59°–60°. 相似文献
14.
We have used the PBE/3z, B3LYP/6-31G, B3LYP/6-31G(d), and B3LYP/6-311G(d) methods to study the conformational mobility of
2,3-dihydro-3-O-(1,4-naphthoquinon-2-yl)-2-oxo-1,4-naphthoquinones (1–4). We have shown that more than 99% of these compounds exist as the major tautomeric form, while differences in the structure
of the Q2H (2,3-dihydro-2-oxo-1,4-naphthoquinones) and Q1,4 (1,4-naphthoquinon-2-yl) moieties lead to qualitative differences in the internal rotation potentials of the ethyl substituents
V(θEt−1) and V(θEt−2), and consequently each of compounds 1−4 exists as six different rotameric forms. For diquinone 3, we have calculated the dependences of the frequencies (ν) and intensities (A) of the normal vibrations on the torsional
angles θEt−1 and θEt−2, and also on the changes in the geometry of the ether bond. We have found that the values of ν and A for the bands in the
carbonyl region of the IR spectrum change little on going from one rotameric form to another, and also for the in-plane bends
of the ether bond, and change considerably for the out-of-plane bends of the ether bond. However, for T ≤ 300 K, there is
no qualitative change in the overall contour, and it can be interpreted based on a simple additive model.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 5, pp. 573–581, September–October, 2006. 相似文献
15.
This paper discusses electromigration in iodine-doped polystyrene in the temperature interval from 300 to 400 K. It is shown
that, because of impurities capable of forming charge-transfer complexes with the macromolecules of the polymer, electrical
conduction occurs by a hopping mechanism.
Fiz. Tverd. Tela (St. Petersburg) 39, 951–952 (May 1997) 相似文献
16.
A. V. Glushkov V. B. Kosarev I. T. Makarov I. E. Sleptsov S. A. Filippov 《JETP Letters》1998,67(6):383-388
Preliminary results are reported from an investigation of the temporal structure of the muon disk in extensive air showers
(EASs) with primary energy E
0≥6×1016eV at distances 100–1500 m from the axis. The investigation is performed at the Yakutsk array using the large muon detector,
which commenced operation in November 1995, with a planned area 184 m2 and a detection threshold E
μ≈0.5· sec θ GeV. For E
0>1018eV it is found that the thickness of the muon disk tends to decrease. This requires substantial changes in our notions of
the development of EASs.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 6, 361–366 (25 March 1998) 相似文献
17.
A. V. Mel’nichuk 《Journal of Experimental and Theoretical Physics》1999,89(2):344-348
The coefficient R(ν) of reflection from the surface of 6H-SiC single crystals is studied in the case in which the long-wavelength optical vibrations
of the lattice are coupled with the electron plasma. It is shown for the first time that the anisotropy of the properties
of electrons and phonons in 6H-SiC gives rise to special features in the spectrum of the coupled vibrations and the transparency
regions. It is found, in particular, that if the axis of the crystal lies in the polarization plane of the incident radiation
(0<θ<90°), for 30 cm−1⩽ν
p⊥<320 cm−1 the spectrum of R(ν) acquires three regions of transparency and opacity, and for ν
p⊥⩾320 cm−1 four such regions, which are absent in an isotropic medium. The width of these regions is found to depend on the electron
concentration in the conduction band and on the angle θ.
Zh. éksp. Teor. Fiz. 116, 646–654 (August 1999) 相似文献
18.
We explore a novel possibility for lowering the solar mixing angle (θ
12) from tri-bimaximal mixings, without sacrificing the predictions of maximal atmospheric mixing angle (θ
23 = 45°) and zero reactor angle (θ
13 = 0°) in the inverted and normal hierarchical neutrino mass models having 2–3 symmetry. This can be done through the identification
of a flavour twister term in the texture of neutrino mass matrix and the variation of such term leads to lowering of solar
mixing angle. For the observed ranges of Δm
212 and Δm
232, we calculate the predictions on tan2
θ
12 = 0.5, 0.45, 0.35 for different input values of the parameters in the neutrino mass matrix. We also observe a possible transition
from inverted hierarchical model having even CP parity (Type-IHA) to inverted hierarchical model having odd CP parity (Type-IHB)
in the first two mass eigenvalues, when there is a change in input values of parameters in the same mass matrix. The present
work differs from the conventional approaches for the deviations from tri-bimaximal mixing, where the 2–3 symmetry is broken,
leading to θ
23 ≠ 45° and θ
13 ≠ 0°.
相似文献
19.
R.P. Malik 《The European Physical Journal C - Particles and Fields》2007,51(1):169-177
We provide an alternative to the gauge covariant horizontality condition, which is responsible for the derivation of the nilpotent (anti-) BRST symmetry transformations for
the gauge and (anti-) ghost fields of a (3+1)-dimensional (4D) interacting 1-form non-Abelian gauge theory in the framework
of the usual superfield approach to the Becchi–Rouet–Stora–Tyutin (BRST) formalism. The above covariant horizontality condition
is replaced by a gauge invariant restriction on the (4,2)-dimensional supermanifold, parameterised by a set of four spacetime coordinates, xμ(μ=0,1,2,3), and a pair of Grassmannian variables, θ and θ̄. The latter condition enables us to derive the nilpotent (anti-)
BRST symmetry transformations for all the fields of an interacting 1-form 4D non-Abelian gauge theory in which there is an explicit coupling between the gauge
field and the Dirac fields. The key differences and the striking similarities between the above two conditions are pointed
out clearly.
PACS 11.15.-q; 12.20.-m; 03.70.+k 相似文献
20.
The temperature dependences of the zero-magnetic-field resistivity ρ and magnetoresistance of the 2D hole gas in GaAs/(AlGa)As
heterostructures are investigated in the temperature interval 0.4–4.2 K. As the temperature T is increased, (i) the resistivity ρ grows with a decreasing derivative dρ/dT, and (ii) the positive magnetoresistance diminishes from about 40% at T=0.4 K to about 1% at T=4.2 K. The results are explained in terms of a temperature-dependent mutual scattering of the holes, accompanied by momentum
transfer between two different spin-split subbands.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 2, 101–106 (25 January 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献