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991.
992.
993.
This paper is mainly concerned with elastic and acoustic properties of vitrous silica besides the computation of phonon frequencies.
Thus the phonon frequencies of vitrous silica have been calculated assuming the electronic bulk modulus,K
e, as equal to zero. New equations have been derived to relate the pressure derivatives of second order elastic constants to
the acoustic Gruneisen’s parameters using both Bhatia-Singh’s parameters and Schofield’s equations. The calculated longitudinal
and transverse Gruneisen’s parameters and the predicted absorption band spectra from Nagendranath’s equation and Bhatia Singh’s
parameters are in good agreement with experiment. The calculated mean acoustic mode Gruneisen’s parameter evaluated from the
pressure derivative of Nagendranath’s equation is also in good agreement with experiment.
An erratum to this article is available at . 相似文献
994.
995.
The Study of Minimax Inequalities, Abstract Economics and Applications to Variational Inequalities and Nash Equilibria 总被引:6,自引:0,他引:6
In this survey, a new minimax inequality and one equivalent geometricform are proved. Next, a theorem concerning the existence of maximalelements for an LC-majorized correspondence is obtained.By the maximal element theorem, existence theorems of equilibrium point fora noncompact one-person game and for a noncompact qualitative game withLC-majorized correspondences are given. Using the lastresult and employing 'approximation approach', we prove theexistence of equilibria for abstract economies in which the constraintcorrespondence is lower (upper) semicontinuous instead of having lower(upper) open sections or open graphs in infinite-dimensional topologicalspaces. Then, as the applications, the existence theorems of solutions forthe quasi-variational inequalities and generalized quasi-variationalinequalities for noncompact cases are also proven. Finally, with theapplications of quasi-variational inequalities, the existence theorems ofNash equilibrium of constrained games with noncompact are given. Our resultsinclude many results in the literature as special cases. 相似文献
996.
997.
We prove the global Markov property for lattice systems of classical statistical mechanics, with bounded spins and finite range interactions. The method uses the one developed by two of us to prove the global Markov property of Euclidean generalized random fields. The result shows that the systems considered have a transition matrix, which together with a distribution on a hyperplane, describes completely the system. 相似文献
998.
V. M. Naumenko 《International Journal of Infrared and Millimeter Waves》1981,2(1):149-158
Interaction of host magnons with impurity magnetic excitations in antiferromagnetic crystals CoCO3 and CoF2 containing substitutional impurity amounting to 10–4 and (4±2)×10–3 (by weight) Mn2+ respectively, has been investigated in the wavelength range 0.35–0.8 mm in a magnetic field of up to 20 T. In the CoCO3+10–4 Mn2+ crystal the impurity line was observed to merge with the AFMR line, which is peculiar to incoherent spectrum rearrangement. In the CoF2+4×10–3 Mn2+ crystal the cross splitting of spectrum was revealed as the impurity lower lying Zeeman level approached the AFMR low frequency mode, peculiar to coherent spectrum rearrangement. In both cases the impurity line intensity increases very much as it approaches the spin-wave band of the crystal. The constant of resonance interaction of the impurity excitation with magnons is determined for CoF2+Mn2+ to be m=18 cm–1. 相似文献
999.
1000.
In the context, some lanthanide (Eu3+, Tb3+ and Sm3+) complexes with conjugated carboxylic acids (pyridine-carboxylic acids derivatives) have been synthesized and characterized. The low temperature fluorescent spectra for these complexes have been measured at nitrogen atmosphere (77 K), indicating that the central Ln3+ ions locate in an equivalent coordination environment with low symmetry for most of these lanthanide complexes belonging to dimeric or polymeric structure. Therefore, the electronic dipole transition (supersensitive transition) (5D0 → 7F2 for Eu3+, 5D4 → 7F6 for Tb3+, 4G5/2 → 6H9/2 for Sm3+) and magnetic dipole transition (5D0 → 7F1 for Eu3+, 5D4 → 7F5 for Tb3+, 4G5/2 → 6H5/2 for Sm3+) show the regular change in the corresponding split number of fluorescent spectra, which can be realized to predict the fine structure of lanthanide complexes. 相似文献