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91.
Z. A. Samoilenko V. D. Okunev S. J. Lewandowski P. Aleshkevych Yu. M. Nikolaenko E. I. Pushenko O. Abal’oshev P. Gierlowski A. N. Bondarchuk A. B. Glot 《Technical Physics》2013,58(8):1144-1151
A metastable hexagonal R-phase is revealed in polycrystalline In2O3-SrO samples, which has the form of a network made up of mesoscopic clusters (60–180 Å in size). The clusters arise from strontium-enriched regions near grain boundaries in the main cubic structure of indium oxide. It is shown that annealing in oxygen at T a ? 300°C saturates dangling bonds between the R-phase and the matrix and makes the system metastable. This state shows up in the presence of (i) solitary diffuse maxima from the R-phase imposed on Debye lines from the main phase in the X-ray diffraction pattern and (ii) the electron cyclotron resonance (ECR) line with g = 1.875. In addition, the sample in this state acquires a high resistivity (ρ ~ 106 Ω cm). Relaxation at T ? 300°C after annealing at T a > 300°C disrupts bonds between the strontium-enriched clusters of the R-phase and the indium oxide matrix. This causes spatial separation of the clusters, disruption of their coherent bonds with the matrix structure, and escape of excess oxygen from the sample along grain boundaries. As a result, a new stable state forms, which is characterized by (i) a series of diffuse maxima from the R-phase imposed on lines assigned to the main phase, (ii) the presence of the ECR line with g = 2 with the line with g = 1.875 retained, and (iii) the transition of the sample to a low-resistivity state (ρ ~ 100 Ω cm). 相似文献
92.
93.
N. G. Samoilenko V. A. Bostandgian Yu. N. Finaeva L. V. Kustova B. L. Korsounskii 《Russian Journal of Physical Chemistry B, Focus on Physics》2015,9(6):926-932
The thermal ignition of a heterogeneous two-phase system of two immiscible liquids in a stirring semibatch reactor was modeled. The model took into account the dispersion of one phase in the other, the mass transfer of a reagent from the disperse phase into the dispersion medium, and the bimolecular exothermal reaction that occurred in the latter. The kinetic dependences of reagent concentrations, the dynamics of reactor heating, and the critical conditions of thermal ignition were studied. It was found that the initial temperature of the reactor had a considerable effect on its dynamic behavior. 相似文献
94.
Mg0.54Zn0.46Fe2O4 ferrites are studied by X-ray diffraction, and different-scale structural groups with short-range, mesoscopic, and long-range atomic orders are revealed in them. These groups are shown to undergo interrelated order-disorder-order phase transitions during high-temperature annealing at 1280°C for 0.5–8.0 h, which are accompanied by maximum changes in the structural parameters.
相似文献95.
N. G. Samoilenko E. N. Shatunova V. A. Bostandzhiyan B. L. Korsunskii 《Russian Journal of Physical Chemistry B, Focus on Physics》2018,12(2):196-199
A plug flow reactor operating on a heterogeneous liquid?liquid system in which an exothermic bimolecular reaction takes place is modeled. The effect of the main governing parameters (Peclet and Damkheler numbers and a dimensionless parameter P characterizing mass transfer between the liquid phases) on the thermal modes of the reactor is examined. Depending on the values of these parameters, one or three steady states can be realized in the reactor. It is established that, with increasing parameter P, the region of multiplicity of steady states expands and shift toward lower values of the Damkohler number. The phenomenon of hysteresis is observed in the region of multiplicity of steady states. 相似文献
96.
S. E. Kichanov A. Kh. Islamov S. A. Samoilenko D. P. Kozlenko A. V. Belushkin V. S. Gurin G. P. Shevchenko E. E. Trusova L. A. Bulavin B. N. Savenko 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2014,8(1):98-103
The features of the formation of Ce-Ti-O complex oxide nanoclusters in a silicate glass are studied by means of the small-angle neutron scattering technique. It is found that bounded regions of density fluctuation of the glass material are formed in the initial glass matrix without the addition of titanium and cerium oxides. These regions could serve as nucleation centers for oxide clusters of cerium and titanium upon their introduction into the matrix. The calculated average size of these inhomogeneities does not exceed 30 ± 1 nm, and their surface volume equals 0.72 ± 3 nm3. A structural mechanism for Ce-Ti-O oxide formation in a silicate glass, in which the nanoclusters are formed within a bounded region of glass material inhomogeneities at low concentrations of the initial cerium oxide (CeO2), is proposed. At high cerium oxide concentrations, oxide nanocluster growth occurs predominantly on the surface of these inhomogeneities. This leads to a sharp change in the nanocluster sizes and their fractal dimension. 相似文献
97.
The magnetic properties of Ba2Cu3O4Cl2 and Sr2Cu3O4Cl2 oxychlorides have been studied. A spontaneous manifestation of diamagnetism has been found at quasi-zero and low fields. The temperature of these transitions coincides with the temperature of the antiferromagnetic ordering in Ba2Cu3O4Cl2 (T NI ≈ 337 K) and Sr2Cu3O4Cl2 (T NI ≈ 386 K). The recorded diamagnetic signal is ?10?4 emu. It is comparable with the percentage of the superconducting phase in the sample. It is supposed that the arising superconductivity is due to the formation of the superconducting clusters with the direct overlap of the copper d orbitals owing to the frustration processes. 相似文献
98.
We find moments of a process of Markov random evolutions in a finite-dimensional space. 相似文献
99.
Burtovoy V. S. Akimenko S. A. Artamonov A. V. Blik A. M. Brekhovskikh V. V. Gorin A. M. Donskov S. V. Inyakin A. V. Kolosov V. N. Kurshetsov V. F. Lishin V. A. Medynsky M. V. Mikhailov Yu. V. Obraztsov V. F. Polyakov V. A. Romanovsky V. I. Rykalin V. I. Sadovsky A. S. Samoilenko V. D. Stenyakin O. V. Uvarov V. A. Filin A. P. Khaustov G. V. Kholodenko S. A. Tchikilev O. G. Yushchenko O. P. Guschin E. N. Duk V. A. Kravtsov V. I. Kudenko Yu. G. Polyarush A. Yu. Filippov S. N. Khudyakov A. A. Bychkov V. N. Zalikhanov B. Zh. Kekelidze G. D. Lysan V. M. 《Journal of Experimental and Theoretical Physics》2020,131(6):928-939
Journal of Experimental and Theoretical Physics - On the statistics of ~1.7 × 108 interactions of positively charged kaons on copper nuclei, coherent events of the K+π0 system production... 相似文献
100.
V. G. Samoilenko 《Ukrainian Mathematical Journal》2004,56(2):351-356
For systems in a magnetic field, we investigate the form sum of an infinite-dimensional energy operator perturbed by a potential. We also investigate changes in the spectrum of the energy operator in the case of its perturbation by a potential. 相似文献