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71.
A. I. Nazarov 《Journal of Mathematical Sciences》2001,107(3):3841-3859
Varying conditions on the weight function f, the author is interested in whether the extremal of the ratio $\inf \frac{{\left\| {\nabla u} \right\|_{Lp} \left( \Omega \right)}}{{\left\| {fu} \right\|_{Lp} \left( \Omega \right)}}{\lambda }_{pq} \left( {\Omega ,f} \right)$ remains symmetric. Here, f is positive almost everywhere in $u \in \mathop {W_p^1 }\limits^{\text{O}} \left( \Omega \right)$ and the infimum is taken over all functions $u \in \mathop {W_p^1 \left( \Omega \right)}\limits^{\text{O}}$ . Bibliography: 23 titles. 相似文献
72.
S. A. Nazarov 《Journal of Mathematical Sciences》2001,107(3):3860-3873
The existence of a small solution to the quasilinear Neumann problem is established in a H\"older class with separated asymptotics. The lower-order asymptotic terms are constructed. The homogeneity exponents of these terms turn out to be dependent on the value of the solution at a conical point. Bibliography: 33 titles. 相似文献
73.
The results of experimental and theoretical investigations of nonlinear acoustic phenomena (nonlinear losses, shift of resonance frequency, generation of the third harmonic, and nonlinear sound-by-sound damping) in polycrystalline zinc nonannealed and annealed resonating rods are presented. The measurements were carried out in the 10(-7)-10(-5) strain range at a frequency of about 3 kHz; the frequency of the weak ultrasonic pulse was about 270 kHz. The experimentally observed phenomena are described in frames of phenomenological equations of state containing elastic hysteresis and dissipative nonlinearity. The nonlinear acoustic parameters of these equations are determined by comparison between theoretical dependencies and experimental results. The influence of structural changes in zinc due to annealing on the nonlinear acoustic phenomena is shown. 相似文献
74.
M. G. Kogan V. I. Galkin K. A. Kotel’nikov R. A. Mukhamedshin S. I. Nazarov S. A. Slavatinskii 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(4):519-521
The ECSim 2.0 package is being developed on the basis of the ECSim software package to simulate the development of nuclear-electromagnetic cascades initiated by different particles in a layered medium. Some characteristics of ECSim 2.0 and the results obtained using this package in simulation of the passage of electrons and γ rays through the gamma block of X-ray emulsion chambers in the Pamir Collaboration experiment are discussed. The results obtained are compared with the data of other researchers. 相似文献
75.
A. V. Beznosov A. A. Molodtsov A. V. Nazarov S. Yu. Savinov O. O. Kudrin 《Thermophysics and Aeromechanics》2007,14(3):411-418
Results of experimental studies on the local characteristics of heat transfer from a lead heat carrier to the surface of a
cooled tube in an annular gap are shown at control and alteration of oxygen admixture content under the conditions of power
circuits with heavy liquid-metal heat-transfer agent. This work is aimed at obtaining the grounded formulas for engineering
calculations of heat transfer surfaces. Investigations were carried out at the lead temperature of 400–500 °C, the average
velocity of heat-transfer agent of 0.1–1.5 m/s, the range of Prandtl number of 0.0123–0.0211 and Peclet numbers of 500–7000.
The heat flux changed within 50–160 kW/m2. Controllable changing content of oxygen admixture changed from the value of thermodynamic activity of oxygen from 10−5-100 to saturation and higher with deposition of lead oxides near the heat-transferring surface. 相似文献
76.
V. E. Nazarov 《Acoustical Physics》2007,53(5):584-588
The perturbation method is used to study nonlinear acoustic effects in solids that feature elastic, hysteresis, or inelastic nonlinearity. It is found that these media exhibit qualitatively different nonlinearity behavior laws, which facilitates classifying them based on the acoustic nonlinearity type. 相似文献
77.
N. N. Gavrilova M. A. Myachina D. V. Ardashev V. V. Nazarov V. V. Skudin 《Kinetics and Catalysis》2018,59(5):635-643
The methods of synthesis of composite membrane catalysts based on Mо2C and Al2O3 support by a sol–gel method were developed. The samples of membrane catalysts with different architectures were developed. The difference in the catalytic activity of membrane catalysts in carbon dioxide conversion of methane depending on the porous structure and morphology of the catalytic layer was studied. 相似文献
78.
79.
80.
A. I. Nazarov 《Journal of Mathematical Sciences》2001,106(3):2989-3014
The Dirichlet problem and the Neumann problem in a wedge with edge of an arbitrary codimension are studied. On the basis of the Green functions of these problems in a cone, estimates for solutions are obtained. Coercive estimates for the solutions are also obtained in the Kondrat'ev spaces. Bibliography: 14 titles. 相似文献