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81.
Multicomponent Diamond-Like Semiconductors Based on the InBV–CdS System: Bulk and Surface Properties
Semiconductors - According to developed methods, in the fields of the mutual solubility of initial binary compounds (InP, InSb, and CdS), solid solutions of the InP–CdS and InSb–CdS... 相似文献
82.
It is proven that under certain conditions, in a limited dielectric medium without losses, there exist nonzero solutions to the homogeneous problem. If the medium is anisotropic, then in the region of inhomogeneity there can be electromagnetic energy and, at the same time, there is no radiation into the surrounding space.
相似文献83.
Multidimensional Systems and Signal Processing - Filter banks are the major signal processing blocks that dissipate large amount of power in a portable digital hearing aid device. The power... 相似文献
84.
Semiconductors - The propagation of solitary acoustic pulses in magnetized quantum electron–hole plasmas of semiconductors has been studied. The effects of an external magnetic field and... 相似文献
85.
Gerus S. V. Lock E. H. Annenkov A. Yu. 《Journal of Communications Technology and Electronics》2021,66(12):1378-1384
Journal of Communications Technology and Electronics - A magnetic system is developed to generate a stationary uniform magnetic field in a relatively large region between the poles of a magnet that... 相似文献
86.
D.V.N. Harish A. Bharatish H.N. Narasimha Murthy B. Anand K.N. Subramanya 《Ceramics International》2021,47(3):3498-3513
Laser ablation of high-temperature ceramic coatings results in thermal residual stresses due to which the coatings fail by cracking and debonding. Hence, the measurement of such residual stresses during laser ablation process holds utmost importance from the view of performance of coatings in extreme conditions. The present research aims at investigating the effect of laser parameters such as laser pulse energy, scanning speed and line spacing on thermal residual stresses induced in tantalum carbide-coated graphite substrates. Residual stresses were measured using micro-Raman spectroscopy and correlated with Raman peak shifts. Transient thermal analysis was performed using COMSOL Multiphysics to model the single ablated track and residual stresses were reported at low, moderate and high pulse energy regimes. The results showed that the initial laser conditions caused higher tensile residual stresses. Moderate pulse energy regime comprised higher compressive residual stresses due to off centre overlapping of the laser pulses. Higher pulse energy (250 μJ), higher scanning speed (1000 mm/s) and moderate line spacing (20 μm) caused accumulation of tensile residual stresses during the final stage of laser ablation. The deviation of experimental residual stresses from COMSOL numerical model was attributed to unaccounted additional stresses induced during thermal spraying process and deformation potentials in the numerical model. 相似文献
87.
N.A. Zhuk M.G. Krzhizhanovskaya N.A. Sekushin V.V. Kharton B.A. Makeev V.A. Belyy R.I. Korolev 《Ceramics International》2021,47(14):19424-19433
The solid solutions based on the pyrochlore-type system Bi2MgNb2-xTaxO9 were formed in the compositional range х = 0–2.0 (Bi1·6Mg0·8Nb1.6-tTatO7.2, t = 0–1.6). The Rietveld method was used to refine the structure for Bi2MgNb2-xTaxO9 (x = 0, 1.0, 2.0). The increasing tantalum content led to the slight decrease in the cubic unit cell parameters from 10.56934 (4) Å for x = 0 and 10.54607 (3) Å for x = 2 (sp.gr. Fd-3m:2). At the same time, tantalum additions suppressed grain growth in the pyrochlore ceramics during sintering and made it possible to obtain materials with an average grain size of 1–2 μm (Bi1·6Mg0·8Ta1·6O7.2). The increase in the Ta5+ concentration led to the decrease in the dielectric permeability from 104 (Bi1·6Mg0·8Nb1·6O7.2) to 20 (Bi1·6Mg0·8Ta1·6O7.2) at room temperature, while the dielectric loss tangent remained lower than 0.002, which is due to the small grain size and the high porosity of the samples. An increase in temperature has practically no effect on the values of the dielectric permittivity in the entire frequency range. The samples have weak through conductivity. The activation energies of electrical conductivity varied in the range of 0.84–1.00 eV, and the less tantalum, the lower the activation energy. The electrical properties of the samples at 200 Hz to 1 MHz are described by the simplest parallel scheme. 相似文献
88.
Olga Yu Kurapova Sergey M. Shugurov Evgenia A. Vasil'eva Daniil A. Savelev Vladimir G. Konakov Sergey I. Lopatin 《Ceramics International》2021,47(8):11072-11079
Ceria-based solid solutions are important materials for high- and medium-temperature electrochemical applications. However, the stabilities of both binary and ternary ceria-based solid solutions are insufficient at elevated temperatures, which limits their application as solid electrolytes or SOFC cathodes. Data on the high-temperature stability of ceria-based ceramics are unavailable in the literature. In the present study, we report a thermodynamic stability investigation of Y2O3-CeO2 and Y2O3-ZrO2-CeO2 solid solutions. The thermal prehistories of binary and ternary systems were investigated using STA, XRD, and ESCA techniques. The vaporization processes were investigated in the temperature range of 1577–2227°С via the Knudsen effusion mass spectrometry technique. Using data on the component activity in solid-phase thermodynamic properties of Y2O3-CeO2 solid solutions, which is represented as the Gibbs energy, the excess Gibbs energy was calculated as a function of the ceria mol. %. It was shown that the reduction of Ce4+ to Ce3+ in Y2O3-CeO2 and Y2O3-ZrO2-CeO2 solid solutions corresponds to less-negative Gibbs energy compared to ZrO2-CeO2 solid solutions. 相似文献
89.
In the present work, two types of shear thickening fluids have been synthesized by using neat and aminosilane functionalized silica nanoparticles and their viscosity curves have been obtained by the rheometer. Based on the values of peak viscosity of synthesized shear thickening fluids, the surface functionalized nanosilica based shear thickening fluid has been chosen as a best candidate due to the high viscosity for impregnation into the neat Kevlar of different layers viz. four (04) and eight (08) layers for velocity impact study. The experimental investigations reveal high energy absorption of shear thickening fluid impregnated Kevlar as compared to the neat Kevlar. The maximum energy absorption 62 J is achieved corresponding to the initial velocity 154 m∙s−1 for 08 layers shear thickening fluid impregnated Kevlar specimen. The data have also been analytically determined and validated with the experimental data. The experimental data have good agreement with the analytical data within the accuracy of around 15 to 20%. The present findings can have significant inferences towards the fabrication of shear thickening fluids using nanomaterials for numerous applications such as soft armors, dampers, nanofinishing and so forth. 相似文献
90.
Zhuchkov V. I. Nazansky S. L. Frolkova A. K. Ganina K. D. 《Theoretical Foundations of Chemical Engineering》2021,55(4):786-791
Theoretical Foundations of Chemical Engineering - Using gas–liquid chromatography, the activity coefficients upon the infinite dilution of the components of the reaction mixture for obtaining... 相似文献