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991.
992.
993.
Couette flow of certain anisotropic fluids 总被引:1,自引:0,他引:1
P. D. S. Verma 《Archive for Rational Mechanics and Analysis》1962,10(1):101-107
994.
995.
The contact layer in the plane couette flow of two immiscible fluids with uniform suction at the stationary plate has been investigated. The effect of suction is to supply an adverse pressure gradient to the fluid which causes back flow near the stationary plate. The streamlines are drawn to show the effect of uniform suction at the stationary plate on the contact layer. 相似文献
996.
The paper presents an analysis of ultrasonic wave generation in water by intensity modulated elliptical Gaussian laser beams.
It is found that generated acoustic radiation is highly directional both in polar and azimuthal directions. An increase in
the assymmetry of the transverse intensity distribution from the Gaussian dependence enhances the source directivity considerably.
An obvious conclusion is that elliptical Gaussian beams are better choice in applications where it is desired to communicate
in an approximately prescribed small solid angle. 相似文献
997.
An attempt has been made to minimize the sources of error involved in the transient probe method for thermal conductivity
determination. Two sensors (thermocouples) are mounted parallel to the needle probe at known distances. This modification
makes it a device for simultaneous conductivity and diffusivity determination. Thermal conductivity and diffusivity for glycerine,
dune sand and mustard seed are determined by this method. Results obtained are compared with those obtained by a calibrated
transient probe for conductivity and by a parallel wire method for diffusivity. Analysis of the results prove it to be a better
instrument over the traditional ones. The technique can also be used as a direct reading device for conductivity and diffusivity
measurements. 相似文献
998.
An analysis of the electronic polarizabilities and sizes of ions in alkali halides has been carried out by considering a relationship according to which the electronic polarizability of an ion should vary as the n th power of its radius. The values of crystal radii, polarizabilities and the exponent “n”have been calculated using the free ion data reported by Pauling. The values of “n” are found to be nearly 3 in most of the crystals suggesting the validity of the polarizability radius cube relation. The polarizabilities and crystal radii calculated in the present study agree well with those estimated by earlier investigators. 相似文献
999.
The fractional ionic character of alkali and silver halide crystals is defined in terms of the deviations from the additivity
rule for polarizabilities of ions. The electronic polarizabilities of ions are calculated using an empirical relationship
according to which the electronic polarizability of an ion can be assumed to be directly proportional to the cube of its radius.
The calculated ionicities indicate that the alkali halides are nearly or more than 90% ionic and silver halides are much less
ionic which is also evident from the Phillips ionicity scale. 相似文献
1000.
G. R. Verma 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1972,23(5):805-814
Summary Non-linear vibrations of beams and membranes are considered using a modified perturbation method based on the Linstedt-Poincare technique, which avoids the secular terms.
Zusammenfassung Mittels einer abgeänderten Störungsmethode, welche auf der Linstedt-Poincaré-Technik basiert und die säkularen Glieder vermeidet, werden nichtlineare Schwingungen von Trägern und Membranen untersucht.相似文献