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51.
It is shown that the three-dimensional Navier-Stokes equation for incompressible fluid can be represented as an equation including
only quaternions as co-ordinate operators and variables. Only the quaternion operations such as a quaternion product and a
quaternion conjugation over these variables are used. 相似文献
52.
The influence of ultrasonic shock treatment on variation in the pearlite structure and properties is studied in the surface layer of carburized steel. It is shown that plastic deformation results in carbon redistribution and formation of new phases. 相似文献
53.
O. Perru F. Ibrahim O. Bajeat C. Bourgeois F. Clapier E. Cottereau C. Donzaud M. Ducourtieux S. Galès D. Guillemaud-Mueller C. Lau H. Lefort F. Le Blanc A. C. Mueller J. Obert N. Pauwels J. C. Potier F. Pougheon J. Proust B. Roussière J. Sauvage O. Sorlin D. Verney 《Physics of Atomic Nuclei》2003,66(8):1421-1427
The PARRNe facility has been used to produce neutron-rich isotopes 83,84Gaby the ISOL method. Their decay has been studied, and β-γ coincidence and γ-γ coincidence data were collected as a function of time. The first two excited levels in 83Ge and the first excited level in 84Ge have been measured for the first time. 相似文献
54.
Lobanovsky L. S. Troyanchuk I. O. 《Journal of Experimental and Theoretical Physics》2003,96(2):331-334
Journal of Experimental and Theoretical Physics - The magnetoresistance effect in the SmCu3Mn4O12 compound with a perovskite-like structure is investigated for the first time. It is found that an... 相似文献
55.
Large eddy simulations of two basic configurations (decay of isotropic turbulence, and the academic plane channel flow) with heat transfer have been performed comparing several convection numerical schemes, in order to discuss their ability to evaluate temperature fluctuations properly. Results are compared with the available incompressible heat transfer direct numerical simulation data. It is shown that the use of regularizing schemes (such as high order upwind type schemes) for the temperature transport equation in combination with centered schemes for momentum transport equation gives better results than the use of centred schemes for both equations. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
56.
O. P. Bobrov S. N. Laptev H. Neuhäuser V. A. Khonik K. Csach 《Physics of the Solid State》2004,46(10):1863-1867
Isochronous relaxation of tensile stresses is measured in a bulk Pd40Cu30Ni10P20 metallic glass in the initial state and after certain thermal treatments. The results of measurements are used to find the energy spectrum of irreversible structural relaxation, from which the temperature dependence of shear viscosity is then calculated. This dependence is also found independently from measurements of creep in the same glass. The calculated viscosity is shown to agree well with the experimental data. 相似文献
57.
O. Yu. Borkovskaya N. L. Dmitruk I. B. Ermolovich R. V. Konakova V. V. Milenin 《Technical Physics》2004,49(3):325-329
The properties of nonrectifying AuGe/GaAs (Al0.4Ga0.6As) contacts exposed to heat treatment, 60Co γ radiation, and γ radiation combined with the application of an electrical bias are studied. A correlation between the
type of interfacial interaction in the contacts and their resistance is found. Results obtained are explained in terms of
a diffusion model with a movable boundary of the metal layer. 相似文献
58.
59.
60.
The kinetics of current decay and partial restoration in planar doped GaAs:Si due to the formation of DX? centers in strong electric fields has been experimentally studied. The existence of thresholds with respect to the field strength and donor concentration is explained. A model of the DX? center formation is proposed, which is based on the notions about variation of the depth and width of a potential well created by planar doping, caused by the redistribution of hot electrons between quantum confinement subbands. As a result, the energy level of DX? centers, which is situated above the potential well depth in the absence of strong field, decreases and falls within the potential well. This makes possible the DX? center formation, provided that hot electrons, occupying the resonance electron levels in the conduction band, simultaneously excite local vibrational modes. 相似文献