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991.
V. A. Kulbachinskiĭ A. Yu. Kaminskiĭ P. M. Tarasov P. Lostak 《Physics of the Solid State》2006,48(5):833-840
The Fermi surface anisotropy of (Bi1?x Sbx)2Te3 single crystals (0.25 ≤ x ≤ 1) was studied by analyzing the angular dependence of the frequency of Shubnikov-de Haas oscillations and the effect of tin and silver doping on the thermoelectric power in these crystals in the temperature range 77 ≤ T ≤ 300 K. It was shown that silver doping of (Bi1?x Sbx)2Te3 mixed crystals produces acceptors, while silver in Bi2Te3 acts as a donor. Tin also exhibits acceptor properties. Both tin and silver doping of p-(Bi1?x Sbx)2Te3 mixed crystals decrease the thermoelectric power due to an increase in the hole concentration. 相似文献
992.
The permittivity of an amorphous insulator consisting of several types of molecules is found. The concepts of polarizability averaged over molecule types and of polarizability fluctuation are introduced, which, when taken into consideration, impart dispersive properties to the permittivity of the medium. It is shown that, near the frequencies at which the average polarizability vanishes, the permittivity depends on the average quadratic fluctuation of the molecular polarizability. Anomalous electromagnetic waves in these frequency intervals are considered. 相似文献
993.
The coherent inelastic processes of the type a → b, which may take place in the interaction of hadrons and γ quanta with nuclei at very high energies (the nucleus remains the same), are theoretically investigated. Analytical formulas for the effective cross-section σcoh(a→b) are obtained. 相似文献
994.
Direct measurement of fluid velocity gradients at a wall by PIV image processing with stereo reconstruction 总被引:1,自引:0,他引:1
Velocity gradient is typically estimated in Particle Image Velocimetry (PIV) by differentiating a measured velocity field,
which amplifies noise in the measured velocities. If gradients near a boundary are sought, such noise is usually greater than
in bulk fluid, because of small tracer displacement, uncertainty in the effective positions of velocity vectors, intense deformation
of tracer patterns, and laser reflection. We consider here a modified form of the Particle Image Distortion (PID) method todirectly calculate velocity gradients at a fixed wall, and refer it as “PIV/IG” (“Interface Gradiometry”). Results from synthetic
2D PIV images suggest our method achieves higher SNR and accuracy than velocity differentiation. Also, we have developed a
procedure to reconstruct three-dimensional velocity gradient at a fixed wall the two non-zero components from PIV/IG data
obtained in stereo views; these equations simplify considerably thanks to the no-slip condition. Experimental data from the
bottom wall of turbulent open channel flow appear to suffer from a form of pixel locking. As with standard PIV, this underlines
the importance of adequate tracer diameter in the images, sufficient seeding density, and of dynamic range of the camera sensor. 相似文献
995.
S. V. Ivanov V. V. Trachevskii O. S. Titova L. A. Zozulya 《Russian Journal of Applied Chemistry》2006,79(10):1712-1714
Experimental data demonstrate that a study of accelerated aging can enable prognostication of the working capacity and storage life of polymeric formulations used in aircraft components on the basis of changes in thermogravimetric constants of these polymeric formulations. 相似文献
996.
997.
V. Z. Khukhunashvili 《Theoretical and Mathematical Physics》1989,79(2):467-469
P. P. Shirshov Institute of Oceanology, USSR Academy of Sciences. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 79, No. 2, pp. 180–184, May, 1989. 相似文献
998.
V. B. Larin 《Ukrainian Mathematical Journal》1989,41(5):532-538
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 41, No. 5, pp. 615–621, May, 1989. 相似文献
999.
1000.