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121.
We discuss problems of the application of various reliability theories in models of optimal design of structures. Using the example of the problem of optimizing (with respect to the minimal mass criterion) the parameters of an inclined spherical shell reinforced by a network of ribs and subject to a random load stated as a nonlinear programming problem we give a comparative analysis of the optimal designs obtained using the theory of Bolotin and the theory of Kapur-Lamberson. One figure. One table. Bibliography: 5 titles.Translated fromMatematicheskie Metody i Fiziko-Mekhanicheskie Polya, Issue 30, 1989, pp. 82–87. 相似文献
122.
Summary The thermal conductivity of YBa2Cu3O7−δ high-T
c superconductor is analysed self-consistently on both normal and superconducting states on the base of the Bardeen-Rickayzen-Tewordt
extended theory to take into account the effects of magnetic field and superconducting fluctuations. It is shown that experimental
data are in a quantitative agreement with theory even if the number and variation intervals of adjustable parameters are substantially
reduced in comparison with previous works. Phonon relaxation rates due to different mechanisms of phonon scattering as well
as the parameters of electron-phonon interaction are estimated. It is shown that thermal conductivity in YBa2Cu3O7−δ is consistent with the BCS model with intermediate electron-phonon coupling λ=1–3 the phonon-electron and electron-phonon
relaxation times near critical temperature are evaluated to be 10−10s and 10−12s, respectively. 相似文献
123.
124.
125.
126.
The reaction of some aliphatic diazo compounds with trans-1-phenyl-1,2-dinitroethylene gave the first representatives of 4-nitroisoxazoline N-oxides, which differ from the unknown 3-nitroisoxazoline N-oxides with respect to their individual physical and chemical properties. 相似文献
127.
Jin M. Jung Yong Yang Dong H. Lee Greg Fridman Alexander Fridman Young I. Cho 《Plasma Chemistry and Plasma Processing》2012,32(1):165-176
The whole blood viscosity (WBV) is one of the major independent indicators for the risk of cardiovascular disease, stroke,
and peripheral arterial diseases. Furthermore, oxidized LDL molecules are known to cause atherosclerotic plaques in arteries,
and it is one of the key components that increase WBV. The present study attempted to reduce WBV by coagulating plasma proteins
and lipid molecules from blood plasma using non-thermal dielectric barrier discharge (DBD) and removing them through filtration.
The DBD treatment was found to produce coagulated particles in blood plasma. After filtration of the coagulated particles,
WBV decreased by 9.1 and 17.7% for both systolic and diastolic blood viscosities, respectively. The present results suggest
that the removal of excess plasma proteins and lipid molecules might be feasible using DBD treatment. 相似文献
128.
G. A. Gorelikov O. A. Kosmachev A. V. Krivtsova Yu. A. Fridman 《Physics of the Solid State》2017,59(3):504-513
The influence of the anisotropic exchange interaction on the phase states of a non-Heisenberg ferromagnet with a magnetic-ion spin S = 1 is studied. It is shown that, depending on the relationships between the parameters of anisotropic exchange interaction and their signs, either a biaxial non-Heisenberg magnet or an Ising magnet are realized in the system. Dynamic properties of the system near orientational phase transitions and transitions in the absolute value of the magnetic moment are studied. Phase diagrams of the system for different relationships between constitutive parameters are plotted. 相似文献
129.
A model of magnetic and magnetoelastic properties of intermetallic compounds has been considered with the inclusion of the
influence of the “giant” magnetoelastic coupling and the biquadratic exchange interaction. The phase transitions as a function
of material constants and temperature have been investigated in the framework of the proposed model. It has been demonstrated
that the ferromagnetic and quadrupole phases can be formed in the system under consideration. In this case, the phase transition
between these phases is a first-order transition and occurs through the intermediate, i.e., quadrupole-ferromagnetic, state.
The dependences of the phase transition temperature on the Heisenberg and biquadratic exchange interaction constants have
been obtained for compounds of the terfenol-D type. 相似文献
130.
Sivan Louzoun‐Zada Qais Z. Jaber Micha Fridman 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(44):15730-15740
The ratio between the dose of drug required for optimal efficacy and the dose that causes toxicity is referred to as the therapeutic window. This ratio can be increased by directing the drug to the diseased tissue or pathogenic cell. For drugs targeting fungi and malignant cells, the therapeutic window can be further improved by increasing the resolution of drug delivery to the specific organelle that harbors the drug's target. Organelle targeting is challenging and is, therefore, an under‐exploited strategy. Here we provide an overview of recent advances in control of the subcellular distribution of small molecules with the focus on chemical modifications. Highlighted are recent examples of active and passive organelle‐specific targeting by incorporation of organelle‐directing molecular determinants or by chemical modifications of the pharmacophore. The outstanding potential that lies in the development of organelle‐specific drugs is becoming increasingly apparent. 相似文献