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51.
A direct central collision of two identical infinite cylindrical bodies is studied. A nonstationary plane elastic problem is solved. The variable boundary of the contact area is determined. A mixed boundary problem is formulated. Its solution is represented by Fourier series. An infinite system of Volterra equations of the second kind for the unknown expansion coefficients is derived by satisfying boundary conditions. The basic characteristics of the collision process are determined numerically depending on the curvature of the frontal surface of the bodies  相似文献   
52.
We present measurements of the resonant inelastic x-ray scattering (RIXS) spectra of the CH(3)I molecule in the hard-x-ray region near the iodine L(2) and L(3) absorption edges. We show that dispersive RIXS spectral features that were recognized as a fingerprint of dissociative molecular states can be interpreted in terms of ultrashort natural lifetime of ~200 attoseconds in the case of the iodine L-shell core-hole. Our results demonstrate the capacity of the RIXS technique to reveal subtle dynamical effects in molecules with sensitivity to nuclear rearrangement on a subfemtosecond time scale.  相似文献   
53.
54.
The results of x-ray diffraction analysis on 1,2e-dimethyl-4a-ethynyl-4e-hydroxy-trans-decahydroquinoline N-oxide hydrobromide corroborated the orientation of the substituents at the nitrogen atom that was determined previously from PMR data.For Communication 5, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 82–85, January, 1993.  相似文献   
55.
The paper presents results of recent experiments, as performed with the PF-1000 and PF-6 Plasma-Focus facilities, which were aimed at investigation of the correlation between processes of the irradiation of different materials of fusion devices and results of this irradiation. Among the irradiated samples there were pure tungsten, tantalum, copper, aluminum, and alloys, based on these metals, various steels, carbon and carbon-based materials, which are designed for plasma facing components or constructional parts of future thermonuclear reactors of the inertial- and magnetic-confinement types. The corpuscular radiation consisted of high-energy (E D>100 keV) deuterium ion beams and fast (v str ≥ 107 cm/s) deuterium-plasma streams. They were investigated by a number of methods with spatial and temporal resolution. Particular attention was paid to the verification of diagnostic techniques, which might be used for time- and space-resolved studies of the interaction process. Correlation of these data with information obtained from subsequent analytical investigation of some of the irradiated specimens, as performed by means of a number of methods typical for material sciences, gives possibility to deduce physical mechanisms of the deuterium implantation and radiation damage of the investigated materials in dependence on the conditions of their irradiation.  相似文献   
56.
The field dependence of the magnetic penetration depth over the entire range of stability and metastability of the Meissner state was determined within the framework of the Ginzburg-Landau theory. A simple interpolation formula is suggested.  相似文献   
57.
Localized stationary modes with frequency in the forbidden region of the elastic vibrations of a diatomic anharmonic lattice are studied by the coupled-wave method. The mechanisms responsible for the brightening of the lattice in the cases of narrow and wide forbidden frequency bands are determined and an analytical expression is found for the stationary gap solitons. Fiz. Tverd. Tela (St. Petersburg) 39, 158–162 (January 1997)  相似文献   
58.
The magnitudes of deviations b(a, f) of entire functions of infinite order from rational functions are studied.  相似文献   
59.
The steady wind currents in the ocean near the edge of an ice sheet simulated by a rigid cover are studied. The characteristic horizontal scales of the problem correspond to several tens of kilometers. In this case, depending on the depth and viscosity of the fluid, the effect of the Coriolis force on its motion may be comparable with the effect of the wind shear stresses applied to the ice-free surface. Taking the Coriolis force into account leads to the formation of a spiral flow structure in the vertical direction.Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No.6, pp. 132–141, November–December, 1992.  相似文献   
60.
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