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1.
International Applied Mechanics - The motion of a solid body with a cavity containing a heavy multilayer ideal incompressible fluid is considered using a linear problem statement. An algorithm for...  相似文献   
2.
Mathematical Notes - The problem of finding the least number of variables of a first-order formula expressing the statement that an input-graph contains a subgraph isomorphic to a given...  相似文献   
3.
We consider the inverse problem of identifying a general source term, which is a function of both time variable and the spatial variable, in a parabolic PDE from the knowledge of boundary measurements of the solution on some portion of the lateral boundary. We transform this inverse problem into a problem of solving a compact linear operator equation. For the regularization of the operator equation with noisy data, we employ the standard Tikhonov regularization, and its finite dimensional realization is done using a discretization procedure involving the space $L^2(0,\tau;L^2(Ω))$. For illustrating the specification of an a priori source condition, we have explicitly obtained the range space of the adjoint of the operator involved in the operator equation.  相似文献   
4.
Crystallography Reports - The formation of β-Si3N4 for subsequent growth of AlGaN and GaN heterostructures of silicon wafers has been studied. It is established that the native oxide layer...  相似文献   
5.
Physics of Atomic Nuclei - We review some results of diagnostics for the electromagnetic characteristics of the heliosphere and of the Earth magnetosphere within the model for cosmic ray modulation...  相似文献   
6.
Russian Physics Journal - Using precursors, prepared by a preliminary mechanical activation of the 3Ni–Al powder mixture in the energy-intensive ball mills with and without a subsequent...  相似文献   
7.
To improve our understanding of the combustion characteristics of propyne, new experimental data for ignition delay times (IDTs), pyrolysis speciation profiles and flame speed measurements are presented in this study. IDTs for propyne ignition were obtained at equivalence ratios of 0.5, 1.0, and 2.0 in ‘air’ at pressures of 10 and 30 bar, over a wide range of temperatures (690–1460 K) using a rapid compression machine and a high-pressure shock tube. Moreover, experiments were performed in a single-pulse shock tube to study propyne pyrolysis at 2 bar pressure and in the temperature range 1000–1600 K. In addition, laminar flame speeds of propyne were studied at an unburned gas temperature of 373 K and at 1 and 2 bar for a range of equivalence ratios. A detailed chemical kinetic model is provided to describe the pyrolytic and combustion characteristics of propyne across this wide-ranging set of experimental data. This new mechanism shows significant improvements in the predictions for the IDTs, fuel pyrolysis and flame speeds for propyne compared to AramcoMech3.0. The improvement in fuel reactivity predictions in the new mechanism is due to the inclusion of the propyne + H?2 reaction system along with ?H radical addition to the triple bonds of propyne and subsequent reactions.  相似文献   
8.
Molecular Diversity - The pandemic outbreak of the Corona viral infection has become a critical global health issue. Biophysical and structural evidence shows that spike protein possesses a high...  相似文献   
9.
Zhuravleva  E. N.  Zubarev  N. M.  Zubareva  O. V.  Karabut  E. A. 《Doklady Physics》2021,66(12):348-352
Doklady Physics - Exact solutions of the classical problem of a plane unsteady potential flow of an ideal incompressible fluid with a free boundary are presented. The fluid occupies a semi-infinite...  相似文献   
10.
Physics of Atomic Nuclei - In an experiment with the SND detector at the VEPP-2000 $$e^{+}e^{-}$$ collider, the cross sections for the processes $$e^{+}e^{-}\to K^{+}K^{-}\pi^{0}$$ and...  相似文献   
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