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21.
A. N. Anisimov V. A. Soltamov I. D. Breev M. M. Khalisov R. A. Babunts A. V. Ankudinov P. G. Baranov 《JETP Letters》2018,108(9):610-615
Optical and radio-frequency physical effects that allow spin manipulations at room temperature using magnetic resonance, effects of anticrossing levels in the ground and excited quadruplet spin states, and cross-relaxation resonances in ensembles of spin color centers in silicon carbide micro- and nanocrystals have been demonstrated. A scanning device where ensembles of spin centers placed on the tip of the cantilever probe of an atomic force microscope serve as sensors of magnetic and temperature fields with a submicron spatial resolution has been considered. 相似文献
22.
E. V. Gushchina A. V. Ankudinov L. A. Delimova V. S. Yuferev I. V. Grekhov 《Physics of the Solid State》2012,54(5):1005-1007
Thin films based on lead zirconate titanate with stoichiometric composition near the morphotropic boundary have been studied using atomic-force microscopy methods. The dependence of the local conductivity on the local polarization direction has been observed for all samples, independently of substrate type, deposition method, and film thickness. It has been shown that the current response to the applied voltage exhibits a long current relaxation, about several tens of seconds, which is two to three orders of magnitude greater than the current relaxation time in an external circuit, associated with the ferroelectric domain switching. The conductivity features have been explained by recharging of traps localized at ferroelectric grain boundaries near electrodes and involved in polarization charge screening. 相似文献
23.
Back Cover: A Planar‐Chiral Rhodium(III) Catalyst with a Sterically Demanding Cyclopentadienyl Ligand and Its Application in the Enantioselective Synthesis of Dihydroisoquinolones (Angew. Chem. Int. Ed. 26/2018) 下载免费PDF全文
24.
A.A. Lavrentyev I.Ya. Nikifororv A.L. Ankudinov 《Journal of Physics and Chemistry of Solids》2003,64(12):2479-2486
The electronic structure of phosphorus-contained sulfides InPS4, Tl3PS4, and Sn2P2S6 was investigated experimentally with X-ray spectroscopy and theoretically by quantum mechanical calculations. The partial densities of electron states calculated with the ab initio multiple scattering FEFF8 code correspond well to their experimental analogues—the X-ray K- and L2,3-spectra of sulfur and phosphorus. The good agreement between theory and experiment was also achieved for K-absorption spectra of S and P in the investigated sulfides. In spite of the difference in the crystallographic structure of InPS4, TI3PS4, and Sn2P2S6 that influence the form of K-absorption spectra, the electronic structure of their valence bands are rather similar. This is due to the strong interaction of the P and S atoms, which are the nearest neighbors in the compounds studied. The electron densities of p- and s-states of phosphorus are shifted by about 3 eV to lower energies in comparison to the analogous electron states of sulfur. This is connected with the greater electro-negativity of sulfur, and is confirmed by the calculated electron charge transfer from P to S. 相似文献
25.
Single-crystal (001)-oriented PbZr0.47Ti0.53O3 and polycrystalline (111)-oriented PbZr0.47Ti0.53O3 thin ferroelectric films were studied using contact electrostatic force microscopy. Local electromechanical response measurements permitted study of the polarization vector distribution in natural and intentionally created polarization nanodomains in films. The principal components of an electromechanical response signal encountered in studies of ferroelectric films (the piezoelectric response and the additional capacitive contribution) were isolated and analyzed. The effect of tip-surface contact stiffness on the capacitive contribution to the electromechanical response signal was demonstrated experimentally and in terms of a model. It was shown that more accurate information on the distribution of the polarization vector in ferroelectric films can be gained by monitoring local variations in the tip-surface contact stiffness. 相似文献
26.
V. S. Shustov N. M. Rubtsov M. I. Alymov A. B. Ankudinov E. V. Evstratov V. A. Zelensky 《Doklady Physics》2018,63(3):104-107
Porous materials with a bulk porosity of more than 68% were synthesized by powder metallurgy methods from a cobalt–nickel mixture. The effect of the ratio of nickel and cobalt powders used in the synthesis of this porous material (including cases when either nickel or cobalt alone was applied) and the conditions of their compaction on structural parameters, such as open and closed porosities and pose size, was established. 相似文献
27.
Andrei A. Krasilin Maksim M. Khalisov Ekaterina K. Khrapova Tatyana S. Kunkel Daniil A. Kozlov Nikolay M. Anuchin Andrey N. Enyashin Alexander V. Ankudinov 《Particle & Particle Systems Characterization》2021,38(12):2100153
Some phyllosilicate compounds have the ability of spontaneous scrolling because of the size mismatch between the covalently bounded metal oxide and silica sheets. Their unique structure and high theoretically predicted Young's modulus (around 210–230 GPa) induce phyllosilicates’ application as reinforcing fillers. However, previous nanomechanical experiments with individual phyllosilicate nanoscrolls are in poor agreement with theory. The main reason for this is the low accuracy of experiments, which leads to large measurement errors compared to measured average values. Here, the study of the mechanical properties of synthetic (Mg1–xNix)3Si2O5(OH)4 phyllosilicates is reported by testing a suspended nanoobject (a nanobridge) with an atomic force microscope (AFM). The Young's modulus of corresponding phyllosilicate model layers is also calculated by means of the density functional theory (DFT). The original AFM approach makes it possible to account for the probe slipping off the nanobridge and determine its boundary conditions. The measured Young's modulus values are considered within the models of surface tension and shear strain contributions. The shear strain appears to have a decisive impact on the measured Young's modulus (from 150 ± 70 GPa to 200 ± 210 GPa) and its spread. 相似文献
28.
A. L. Ankudinov 《Fluid Dynamics》2009,44(4):606-611
Macroscopic equations obtained as a thin-layer version of the 13-moment Grad equations derived from kinetic considerations
are used for describing the translationally nonequilibrium monatomic gas flow in a hypersonic free jet boundary layer formed
in the wake behind a wedge. This model makes it possible to investigate flows with strong violations of equilibrium with respect
to the translational degrees of freedom. A method of constructing the solution of this kinetically justified problem based
on the solution of an analogous problem in the Navier-Stokes interpretation is proposed. It is established that for the kinetic
variant of the problem considered the gas flow velocity distribution along the separating streamline in a plane orthogonal
to the wedge generator coincides with the distribution obtained in solving the Navier-Stokes variant. It is found that taking
into account the nonequilibrium nature of the flow with respect to the translational degrees of freedom of the gas particles
has no effect on the base pressure and the wake angle. 相似文献
29.
B. O. Shcherbin A. V. Ankudinov A. V. Kiyuts O. S. Loboda 《Physics of the Solid State》2014,56(3):531-537
A method for studying the force interaction in dynamic modes of the atomic force microscope has been considered. Direct measurements of the maximum impact force in the amplitude modulation mode have been performed. It has been shown that the results of analytical calculations are in agreement with numerical simulation, but differ from experimental data by a factor of 1.5. The major factors affecting the results have been analyzed. 相似文献
30.
E. V. Astrova V. A. Tolmachev G. V. Fedulova V. A. Melnikov A. V. Ankudinov T. S. Perova 《Applied Physics A: Materials Science & Processing》2010,98(3):571-581
The optical properties of one-dimensional photonic crystals (1D PCs), fabricated by electrochemical etching of periodic wall
arrays on n-type (100) Si substrates, are investigated in this study. Several 1D PCs were fabricated with lattice periods varying from
4 to 7 μm and with trench depths in the range 160–210 μm. In-plane reflection spectra of the photonic structures at different
depths were registered over a wide spectral range of 1.5–15 μm using Fourier Transform Infra-Red (FTIR) micro-spectroscopy.
Some of the features observed in the reflection spectra of the structures investigated are believed to be as a result of interface
roughness. A corrugated side-wall surface, an artifact of the fabrication technique, results in the degradation of optical
reflection characteristics, principally mainly in the near IR spectral range, and the emergence of optical anisotropy. As
a result of the periodicity, modulation of the reflection spectra, that is, the difference between the maxima and minima of
the interference fringes, reached a value of 95% in the mid-infrared. The optical properties of the structures investigated
indicate that they show promise for microphotonics applications. 相似文献