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101.
102.
N.S. Andreev 《Journal of Non》1978,30(2):99-126
A kinematic theory of light scattering and modern concepts of phase-separation theory were used to examine the most typical experimental results obtained from the study of light scattering by glasses. The examination was made by taking into account the positions of figurative points in the immiscibility diagram. It has been shown that the anomalous phenomena (the predominant light scattering into the backward semi-sphere and the spectral dependence of intensity of type λ?p, where p > 4) arise in four cases: at the stage of decomposition when the figurative point lies in both the binodal and spinodal regions; after the completion of the decomposition stage when interparticle interference is essential; and in the one-phase region when the concentration fluctuations tend to a higher equilibrium level of development. In each case these phenomena are due to the sign-changed behavior of the dielectric constant and to the existence of a range of negative values in the correlation function. The processes of complete or partial homogenization of the glass are characterized by either the gradual disappearance of anomalous phenomena or the appearance of normal scattering due to the increase in space extension of the inhomogeneity regions at their dissolution. 相似文献
103.
A. Kokh E. Simonova A. Maillard R. Maillard V. Svetlichnyi Yu. Andreev A. Kragzhda A. Kuznetsov K. Kokh 《Crystal Research and Technology》2016,51(9):530-533
The bulk crystals of LiBa12(BO3)7F4 were obtained from two flux compositions by the top seeded solution growth method. Crystals grown from BaCO3:BaF2:H3BO3:Li2CO3 = 3:3:3:1 charge were found to have a distinct linear dichroism effect at 0.35–0.65 and around 0.73 μm. This suggests application of the material in the production of polarizing filters and attenuators for visible range lasers. 相似文献
104.
A. V. Ruseikina S. I. Kol’tsov O. V. Andreev L. A. Pimneva 《Russian Journal of Inorganic Chemistry》2017,62(12):1632-1637
The crystal structures of the first prepared EuLnAgS3 (Ln = Gd and Ho) compounds, which have two polymorphs, were determined by X-ray powder diffraction. α-EuLnAgS3 phases are isostructural to BaErAgS3 (monoclinic crystal system, space group C2/m): a = 17.3168(10) Å, b = 3.9683(2) Å, c = 8.3174(4) Å, β = 103.94° (EuGdCuS3); a = 17.1729(12) Å, b = 3.9367(3) Å, c = 8.2905(6) Å, β = 103.9° (EuHoCuS3). β-EuLnAgS3 phases belong to the AgBiS2 structure type (cubic crystal system, space group Fm-3m): a = 5.739(2) Å (EuGdCuS3) and a = 5.678 Å (EuHoCuS3). In the α-EuLnAgS3 crystal structure, LnS6 octahedra and AgS5 trigonal bipyramids share edges to form a three-dimensional (3D) structure with channels accommodating Eu2+ ions. A decrease in Ln3+ ionic radius gives rise to the crystal-chemical contraction of the 3D structure. 相似文献
105.
Phase equilibria in the isothermal (970 K) and polythermal LaCuS2–EuS, Cu2S–EuLaCuS3, LaCuS2–EuLa2S4, and EuLaCuS3–EuLa2S4 sections of the Cu2S–La2S3–EuS system have been studied. EuLaCuS3 (annealing at 1170 K) is of orthorhombic system, space group Pnma, a = 8.1366(1) Å, b = 4.0586(1) Å, c = 15.9822(2) Å, is isostructural to Ba2MnS3, and incongruently melts by the reaction EuLaCuS3cryst (0.50 EuS; 0.50 LaCuS2) ? 0.22 EuS SS (0.89 EuS; 0.11 LaCuS2) + 0.78 liq (0.39 EuS; 0.61 LaCuS2); ΔН = 52 J/g. The Cu2S–La2S3–EuS system has been found to contain five major subordinate triangles. At 970 K, tie-lines lie between EuLaCuS3 and the Cu2S, EuS, LaCuS2, and EuLa2S4 phases and between the LaCuS2 phase and the γ-La2S3–EuLa2S4 solid solution. Eutectics are formed between LaCuS2 and EuLaCuS3 at 26.0 mol % of EuS and T = 1373 K and between EuLaCuS3 and EuLa2S4 at 29.0 mol % of EuLa2S4 and T = 1533 K. 相似文献
106.
V. N. Andreev E. V. Ovsyannikova N. M. Alpatova 《Russian Journal of Electrochemistry》2010,46(9):1056-1062
Interaction between the anilinium cation and copper tetrasulfophthalocyanine anion (CuTSPc) was studied in an aqueous sulfuric
acid solution using electronic absorption spectra. It was shown that up to 0.15 M aniline could be introduced into the solution
at the dye concentration of 10−3 M, after which a solid deposit of a complex (salt) between the anilinium cation and copper tetrasulfophthalocyanine anion
started precipitating rapidly. The effect of the dye on the kinetics of aniline polymerization on conducting glasses and on
the properties of the polymer obtained was studied. It was found that phthalocyanine accelerates electropolymerization of
aniline and is immobilized within the polymer matrix. It was shown that the self-catalytic synthesis mechanism characteristic
of polyaniline is also preserved in the case of the composite of polyaniline-copper tetrasulfophthalocyanine. 相似文献
107.
Under study is an invariant solution of the equations of thermal diffusive convection which describes a stationary process
of a binary mixture flow in a vertical layer under the action of the pressure gradient and the buoyancy force that depends
nonlinearly on temperature and concentration. Some general properties of this solution are established and an existence theorem
is proved. Analysis of the numerical solution of the problem is carried out in the cases of a power-law and exponential dependence
of the buoyancy force on its argument. 相似文献
108.
Resonant microwave absorption by two-dimensional electrons has been measured using coplanar and strip methods. The influence
of the edge of a two-dimensional system on the dispersion of edge magnetoplasmons has been studied. It has been found that
the edge width can be varied within wide limits (by almost two orders of magnitude) by changing the etching depth of the crystal.
It has been shown that the edge of the electron system in the case of etching through the quantum well has a width of about
0.2 μm, whereas the edge in the case of shallow etching (e.g., down to the donor layer) is smooth and can be as wide as 12
μm. The influence of a logarithmic factor, depending on the edge width of the electron system, on edge magnetoplasma excitations
dispersion has been studied. 相似文献
109.
We have constructed a two-phase analytical model of acceleration of ions in a two-layer laser target. The first phase of acceleration
is isothermic and covers the action time of the laser pulse, while the second phase is adiabatic and occurs after the end
of the laser pulse. The maximal ion energy is obtained as a function of parameters of the laser pulse and target. We compare
analytical results with PIC calculations and show that the theory is adequate. 相似文献
110.
An analytical model of K
α radiation of thin laser targets has been developed. It has been shown that, for such targets, the motion of fast electrons
is significant not only in the target itself but also in vacuum. The considered dependences for the free path length of a
fast electron and for the absorption coefficient of laser radiation on the laser intensity with allowance for the electron
motion in vacuum make it possible to match the results of the proposed model with the experimental data on generation of K
α radiation in wide ranges of laser intensities (1018–1021 W/cm2) and thicknesses (1–100 μm) of targets. 相似文献