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31.
32.
A note on unsteady unidirectional flows of a non-Newtonian fluid 总被引:8,自引:0,他引:8
Exact solutions are established for a class of unsteady unidirectional flows of an in compressible second grade fluid wherein inertial effects are not ignored. Amongst the several interesting flows which belong to this class are the flow due to a rigid plate oscillating in its own direction, the flow between two rigid boundaries one of which is suddenly started and the time-periodic Poiseuille flow due to an oscillating pressure gradient. 相似文献
33.
Arguments are presented to show that the BCS theory of superfluidity in its original form may not be applicable to neutron star matter over a wide range of density. 相似文献
34.
35.
36.
The second law of thermodynamics in nonextensive statistical mechanics is discussed in the quantum regime. Making use of the convexity property of the generalized relative entropy associated with the Tsallis entropy indexed by q, Clausius' inequality is shown to hold in the range q in (0, 2]. This restriction on the range of the entropic index, q, is purely quantum mechanical and there exists no upper bound of q for validity of the second law in classical theory. 相似文献
37.
Jackson YA Rajagopal D Bendolph J Guillory M Lakshmikantham MV Yang J Cava MP 《Organic letters》2003,5(11):1883-1885
[reaction: see text] The preparation of 1,3,5,7-tetramethyl-4,8-dihydrobenzo[1,2-c:4,5-c']dithiophene-4,8-dione and its conversion to the corresponding mono- and dithione are described. 相似文献
38.
We present the dispersion relations for quasiparticle excitations about the color-flavor locked ground state of QCD at high baryon density. In the presence of condensates which pair light and strange quarks there need not be an energy gap in the quasiparticle spectrum. This raises the possibility of gapless color superconductivity, with a Meissner effect but no minimum excitation energy. Analysis within a toy model suggests that gapless color superconductivity may occur only as a metastable phase. 相似文献
39.
40.
The IR and Raman spectra are measured and analysed for sodium pyrophosphate decahydrate. The spectra are interpreted on the
basis of P2O
7
4−
ion and water vibrations. The observed results fit with the features predicted for the factor goup model. The appearance
of two sets of frequencies in the stretching and bending regions of water suggests the existence of two kinds of water molecules
in the crystal. This is confirmed by deuterium substitution. 相似文献