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排序方式: 共有10000条查询结果,搜索用时 8 毫秒
191.
Local and nonlocal coercive estimates in Lebesgue, Hölder, and Morrey–Campanato spaces are proved for solutions of linear stationary systems of hydrodynamic type. For this purpose, the technique proposed by Italian mathematicians for the study of solutions to equations and systems of elliptic and parabolic types is developed. Bibliography: 14 titles. 相似文献
192.
S.V.N Bhaskara Rao T.K. Balasubramanian 《Journal of Quantitative Spectroscopy & Radiative Transfer》2004,87(2):203-210
Fresh computations of rovibrational matrix elements of the polarizability α[=(α||+2α⊥)/3] and the polarizability anisotropy γ(=α||−α⊥) of the heteronuclear isotopomers, HD, HT, and DT, of the hydrogen molecule are presented. The computations combine the most accurate polarizability functions α(R) and γ(R) (R being the bond distance) on the one hand and the most accurate adiabatic potential on the other. The calculations are extended to the product operators xα and xγ where x is the centre of mass to centre of charge separation in the heteronuclear species. The latter matrix elements are needed, additionally, for elucidating the absorption intensities of some of the zero-phonon rovibrational transitions peculiar to the heteronuclear species in the crystalline phase. 相似文献
193.
The results of investigations of the rheological characteristics and electrical resistance of the suspensions of carbon black in vaseline oil under the effects of shear and vibration were presented. The investigations are carried out on an original unit that allowed one to simultaneously subject the suspensions to shear deformation and orthogonal vibration. The electrical resistance was also measured in an ac pulsed low-voltage mode. Possible mechanisms of the suspension conductivity were considered depending on the regime of dynamic action. 相似文献
194.
Electrohydrodynamic instability in homeotropically oriented nematic samples of 4'-n-octyl-4-cyano-biphenyl and 4'n-alkyloxy-4-cyanobiphenyl, (n = 8.9) have been studied in an a.c. electric field. The domain patterns during the instability in these compounds in a very low frequency a.c. field are very similar to those in a d.c. field. The domain patterns observed at higher frequencies have been identified as 'maltese crosses' or 'crossed isogyres'. The electro-convective 'isotropic' flows near the electrode play an important role in the observed instability. 相似文献
195.
G Padmaja A V Ravi Kumar V Vidyalal P Radhakrishnan V P N Nampoori C P G Vallabhan 《Pramana》1989,32(5):L693-L698
Laser induced plasma emission spectra from highT
c superconducting samples of YBa2Cu3O7 and GdBa2Cu3O7 obtained with 1.06μm radiation from a Q switched Nd:YAG laser beam has been analysed. The results clearly show the presence of diatomic oxides
in addition to ionized species of the constituent metals in the plasma thus produced. 相似文献
196.
197.
P. P. Kirpichok N. B. Voronina A. F. Sitnikov V. Ya. Garmash 《Russian Physics Journal》1989,32(1):26-30
The effect of rare-earth oxides on the properties of anisotropic barium ferrites has been studied by x-ray structural and Mössbauer methods. Additions of SrCO3, as well as SrCO3 and La2O3, SrCO3 and Pr6O11, SrCO3 and Nd2O3, SrCO3 and Sm2O3 in amounts of 7.5 mole % Sr and 10 mole % rare-earth element to grade-A barium powder results in the substitution of barium ions by Sr and rare-earth ions; consequently, the energy of magnetic anisotropy changes and the technically important parameters Br and (BH)max increase.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 34–39, January, 1989. 相似文献
198.
N. Vogel 《等离子体物理论文集》1989,29(1):11-24
The stepwise increase of the burning voltage of short break arcs has been found not only in a gas but also in vacuum. It is suggested that the effect is associated with the occurrence of a positive anode fall which enhances ionisation phenomena near the anode. This view is supported by the simultaneous registration of arc current, burning voltage, light emission from the anode region, of spectral lines of ions, atoms and continuum from the near anode plasma. The phenomena occur beyond a critical gap distance which can be related to the characteristic geometry of the discharge. 相似文献
199.
D. B. Kayumova Yu. P. Syrnikov N. V. Penkina M. N. Rodnikova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(10):1634-1635
The structural relaxation time for series of various liquids (alkanes, aliphatic alcohols, and diols) are calculated from published data on the shear viscosity and the heat of evaporation per unit volume. Liquids having a 3D H-bond network (diols) are characterized by relaxation times one to two orders of magnitudes longer than those typical of liquids without such a network (alkanes and aliphatic alcohols). 相似文献
200.
N.C. Apreutesei 《Journal of Mathematical Analysis and Applications》2003,288(2):833-851
Of concern is the existence and uniqueness of the solution to a class of abstract second-order difference equations. They are the discrete version of some evolution equations which are intensely studied. Some asymptotic behavior results are established. The periodic solutions are also investigated. We use the theory of the maximal monotone operators in Hilbert spaces. An application to a partial differential equation is given. 相似文献