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91.
Kishida I Koyama Y Kuwabara A Yamamoto T Oba F Tanaka I 《The journal of physical chemistry. B》2006,110(16):8258-8262
Migration of Li+ ions via the vacancy mechanism in LiX (X = F, Cl, Br, and I) with the rocksalt and hypothetical zinc blende structures and Li2X (X = O, S, Se, and Te) with the antifluorite structure has been investigated using first-principles projector augmented wave calculations with the generalized gradient approximation. The migration paths and energies, determined by the nudged-elastic-band method, are discussed on the basis of two idealized models: the rigid-sphere and charged-sphere models. The trajectories and energy profiles of the migration in these lithium compounds vary between these two models, depending on the anion species and crystal structure. The migration energies in LiX with both the rocksalt and hypothetical zinc blende structures show a tendency to decrease with increasing periodic number of the anion species in the periodic table. This is consistent with the widely accepted view that anion species with large ionic radii and high polarizabilities are favorable for good ionic conduction. In contrast, Li2O exhibits the lowest migration energy among Li2X compounds, although O is the smallest among the chalcogens, indicating that electrostatic attractive interactions play the dominant role in the inter-ion interactions in Li2O and, therefore, in the ion migration. 相似文献
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93.
Let G(p,n) and G(q,n) be the affine Grassmann manifolds of p- and q-planes in Rn, respectively, and let be the Radon transform from smooth functions on G(p,n) to smooth functions on G(q,n) arising from the inclusion incidence relation. When p<q and dimG(p,n)=dimG(p,n), we present a range characterization theorem for via moment conditions. We then use this range result to prove a support theorem for . This complements a previous range characterization theorem for via differential equations when dimG(p,n)<dimG(p,n). We also present a support theorem in this latter case. 相似文献
94.
Fumihiko Maekawa Okiru Komine Katsushige Sato Tomoyuki Kanamatsu Motoaki Uchimura Kohichi Tanaka Hiroko Ohki-Hamazaki 《BMC neuroscience》2006,7(1):75
Background
Imprinting behavior is one form of learning and memory in precocial birds. With the aim of elucidating of the neural basis for visual imprinting, we focused on visual information processing. 相似文献95.
We consider the Cauchy problem for the generalized Ostrovsky equation where f(u)=|u|ρ−1u if ρ is not an integer and f(u)=uρ if ρ is an integer. We obtain the L∞ time decay estimates and the large time asymptotics of small solutions under suitable conditions on the initial data and the order of the nonlinearity. 相似文献
utx=u+(f(u))xx,
96.
Differential scanning calorimetry (DSC) thermograms, X-ray diffraction (XRD) analysis, electrical conductivity (σ), and 7Li NMR spectroscopy characterization of n-C m H(2m?+?1)COOM solids (M = Li, Na, K; m?=?13, 15, 17, 19, 21) and mixed crystals n-C21H43COOLi x K(1???x) (0.25?≤?x?≤?0.75) was performed as a function of temperature. DSC thermograms of n-C m H(2m?+?1)COOM revealed several solid-solid phase transitions with large entropy changes. Electrical conductivity studies established that n-C m H(2m?+?1)COOLi crystals are poor electrical conductors. In contrast, n-C m H(2m?+?1)COOK salts were found to have σ values of 10???7–10???8 S·cm???1. Since the crystal structures and phase-transition temperatures of both n-C m H(2m?+?1)COOLi and n-C m H(2m?+?1)COOK crystals were similar, they were able to form mixed crystals with the structure n-C x H(2m?+?1)COOLi x K(1???x). DSC thermograms of the mixed crystals showed a small entropy change at the melting point (ΔS mp?<?13 J K???1 mol???1), in addition, large ΔS values at the solid-solid phase transition temperature. The σ values obtained for mixed crystals were roughly one order of magnitude greater than those determined for n-C21H43COOK crystals. 7Li NMR spectra of the mixed crystals recorded at various temperatures suggested that the self-diffusion of Li?+? ions was excited in the highest-temperature solid phase. Based on these results, we have classified these mixed crystals as rotator crystals. 相似文献
97.
ABSTRACT We present an algorithm to construct the automorphism group of a finite p-group. The method works down the lower exponent-p central series of the group. The central difficulty in each inductive step is a stabiliser computation; we introduce various approaches designed to simplify this computation. 相似文献
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