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611.
Summary A detailed XPS study of the lithium-intercalated NiPS3 specimens was performed at the 2p, 3p, 3s core levels of the nickel atoms and at the 2p core levels of the sulphur and phosphorous atoms for various lithium contents. Comparison of the Ni 2p, 3p and 3s XPS spectra corresponding to NiPS3 and Li
x
NiPS3 systems shows some evident trends. In particular, a shift of the Ni main line towards lower binding energies, a decrease
in the intensity of the Ni 3p, 2p satellite structures and a change in the full width at half maximum of the Ni 3s band with lithium content are observed. All these findings suggest a change in the 3d electron configuration for high lithium concentrations. As regards the cluster (P2S6)4−, with the addition of lithium, a P 2p main line shift towards higher binding energies is noted, while the S 2p peak shifts towards lower binding energies. These results are discussed in comparison with previous physical measurements
concerning the nickel reduction process and the related electronic modifications.
The authors of this paper have agreed to not receive the proofs for correction. 相似文献
612.
We prove existence and regularity results for a general inequality including fixed point problems, variational and quasi variational inequalities. Examples of such problems are considered. 相似文献
613.
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615.
Umberto Bianchi Carla Cuniberti Enrico Pedemonte Corrado Rossi 《Journal of Polymer Science.Polymer Physics》1969,7(5):845-853
The conformational energy contribution (ΔUconf) to the heat of solution in polymer-solvent systems is presented and discussed in connection with chain conformational properties. In particular, ΔUconf has been discussed in terms of various possible mechanisms of coil deformation. 相似文献
616.
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618.
The potential is a static solution to the classical theory of non-abelian gauge fields coupled to a point magnetic source, for any matrix in the Lie algebra of the gauge group G. This solution is rotationally invariant if the eigenvalues of in the adjoint representation of G are quantized in half-integer units, but is stable to small perturbations only if all non-vanishing eigenvalues are . In this paper, for the gauge groups G = SU(N), it is shown which sets of eigenvalues of are consistent with the group structure, which consistent sets are gauge inequivalent, and which consistent gauge inequivalent sets correspond to stable monopoles. It is found that there are N inequivalent stable monopoles, including the trivial case . Equivalence here is with respect to non-singular gauge transformations—the symmetry transformations of the classical theory. Singular gauge transformations are, in contrast, not symmetries but they are nevertheless useful for classifying solutions and for relating the above concept of local stability to the global, or topological, stability associated with the Dirac strings. In this context, it is shown that there are N distinct topological classes of monopoles, with the group structure of the center of SU(N), that each class contains exactly one stable monopole, and that any other monopole in the same class has a strictly larger value of the magnetic charge magnitude . This leads to an interesting physical picture of local stability as a consequence of the minimization of magnetic energy. The paper concludes with some comments on related topics: the empirical absence of magnetic charge, `t Hooft's calculation of magnetic energy, magnetic confinement, and spontaneously broken theories. 相似文献
619.
We show that with a suitable twist the finite-temperature twisted Eguchi-Kawai model reproduces the planar perturbation expansion of the full Wilson theory in the weak coupling sector. 相似文献
620.