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The pressure dependence of the experimental 7Li NMR spectra is reported for first stage lithium graphite (LiC6) intercalation compound at temperatures T = 232 and 293 K. This experiment together with the presented point charge model calculation of the 7Li quadrupole coupling constant allows an unambiguous determination of the sign of e2qQ/h which is negative: at p = 1 bar and T = 232 K. The averaged location of the electrons transferred from the Li intercalant to the graphite layers, as estimated in this study, is in excellent agreement with earlier theoretical energy-band calculations. The compressibility of LiC6 in the c-direction is predicted to be kc = 1.7 × 10-12cm2dyn-1, it agrees with estimates derived from the available phonon dispersion relations. 相似文献
15.
Mesophase behaviour of 2,5-dibenzoyloxy-p-benzoquinone derivatives and tetrahydrobenzene tetraesters
Sibylle Berg Volker Krone Helmut Ringsdorf Udo Quotschalla Helmut Paulus 《Liquid crystals》1991,9(2):151-163
The synthesis of 2,5-dibenzoyloxy-p-benzoquinone derivatives, their products after reduction and tetraesters from tetrahydroxybenzene prepared from those products is described. Their phase behaviour was investigated by differential scanning calorimetry and polarizing microscopy and is discussed in terms of their detailed structure. 相似文献
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In this article we prove a local existence and uniqueness theorem for the Kadomtsev-Petviashvili Equation (u
t
+u
xxx
+uu
x
)
x
−u
yy
=0) in the Sobolev spaces of orders≥3, with initial values in the same spaces, and periodic boundary conditions. This theorem improves previous results based
upon the application of singular perturbation techniques. 相似文献
18.
Jonas Sderberg 《Journal of Algebra》2004,280(2):610-623
In order to use dualization to study Hilbert functions of artinian level algebras we extend the notion of level sequences and cancellable sequences, introduced by Geramita and Lorenzini, to include Hilbert functions of certain artinian modules. As in the case of algebras a level sequence is cancellable, but now by dualization its reverse is also cancellable which gives a new condition on level sequences. We also give a characterization of the cancellable sequences involving Macaulay representations. 相似文献
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Gaven J. Martin Volker Mayer 《Transactions of the American Mathematical Society》2003,355(11):4349-4363
We consider rigidity phenomena for holomorphic functions and then more generally for uniformly quasiregular maps.