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131.
S. Fujita 《Solid State Communications》1975,17(8):915-917
The low temperature mobility μ limited by charged impurities in very pure semiconductors (Ge) is interpreted in terms of the Coulomb collision in medium. The theory yields a peculiar dependence in temperature T and charged impurity concentration . 相似文献
132.
We introduce certain families of elliptic functions involving the Weierstrass ℘-function via q-series systematically and investigate their analytic and algebraic properties. Especially, we give examples of non-linear
algebraic ordinary differential equations satisfied by some such elliptic functions.
2000 Mathematics Subject Classification: Primary–11M36, 33E05 相似文献
133.
134.
135.
We investigate the adiabatic and dynamical natures of the lattice relaxation of excitons in strongly coupled electron-phonon (e-ph) systems using the extended Peierls-Hubbard model, so as to clarify the possible mechanisms of the photoinduced structural phase transition (PISPT) via multi-photon. Focusing on the growth process of relaxed domains that is induced by multi-photoexcitation, we calculate the adiabatic potential energy surfaces relevant to the nonlinear lattice relaxations of excitons in this process. Calculated potentials lead to an essential model of a multi-stepwise potential-crossing (MSPC) system that is composed of many displaced harmonic oscillators as an elementary process of the domain growth in the strongly coupled e-ph systems. We also investigate the dynamical natures in such MSPC systems calculating the time-developments the excited wave packet in this system using the density operator. It is concluded from calculated results that the system possibly develops from the lowest-energy potential state to the higher ones by the effect of the photoexcitations followed by the lattice relaxations. 相似文献
136.
It is easy to see that in a connected graph any longest paths have a vertex in common. For , Skupień in 1966 obtained a connected graph in which some longest paths have no common vertex, but every longest paths have a common vertex. It is not known whether every longest paths in a connected graph have a common vertex and similarly for 4, 5, and longest path. Fujita et al. in 2015 give an upper bound on distance among longest paths in a connected graph. In this paper we give a similar upper bound on distance between longest paths and also for longest paths, in general. 相似文献
137.
We introduce a Selberg type zeta function of two variables which interpolates several higher Selberg zeta functions. The analytic continuation, the functional equation and the determinant expression of this function via the Laplacian on a Riemann surface are obtained.Mathematics Subject Classifications (2000). Primary 11M36, Secondary 33B15 相似文献
138.
Munetaka Takeuchi Yasuo Kameda Yasuhiro Umebayashi Sari Ogawa Takaaki Sonoda Shin-ichi Ishiguro Miho Fujita Mitsuru Sano 《Journal of Molecular Liquids》2009,148(2-3):99-108
Self-diffusion coefficients of Li+ DLi+, PF6− DPF6− and solvent propylene carbonate (PC) DPC in LiPF6−PC solutions were determined at 298 K by the pulse gradient spin echo (PGSE) NMR technique over the salt concentration range of 0.1–3.0 M (M = mol dm– 3). The order of the diffusion coefficients was found to be DLi+ < DPF6− < DPC over the concentration range examined, and they were monotonically decreased with increasing the salt concentration. Haven ratio Λ/ΛNMR, where Λ and ΛNMR represent the ionic conductivity measured electrochemically and that estimated via the Nernst-Einstein equation using the diffusion coefficient, respectively, was evaluated as the measure of the ion–ion interaction in the LiPF6–PC solutions. Though Λ/ΛNMR values for LiPF6-solutions decrease with increasing the salt concentration, they were greater than those for LiBF4–PC solutions over the whole concentration range examined, which indicates that the ion pair formation ability of PF6– ion is weaker than that of the BF4– ion. The smaller value of the ionic conductivity for the highly concentrated LiPF6–PC solution (above 2.0 M) than that of the LiBF4-solutions can be attributed to the more rapidly increased viscosity relative to the LiBF4-solution. Classic molecular dynamics (MD) simulations for the respective LiPF6 and LiBF4-solution of 0.5 and 1.0 M were also carried out based on the effective pair potentials. Diffusion coefficients, ionic conductivity and Haven ratio for these solutions were calculated from MD trajectories, and they qualitatively agree with those evaluated by experiments. Pair correlation functions gLiO(r) (for Li+–O (PC) pair) and gLiPF6(r) (for Li+–PF6– pair) or gLiBF4(r) (for Li+–BF4– pair) revealed that the lithium ion weakly forms the contact ion pairs with PF6–, whilst strongly with BF4–, which supports the present experimental results. Moreover, the simulation results show that both anions in the contact ion pairs predominantly take the monodentate form, which is in contrast to the multidentate coordination predicted by ab initio calculation in gas phase. 相似文献
139.
140.
The present study was designed to show the applicability of scanning ion conductance microscopy (SICM) for imaging different types of biological samples. For this purpose, we first applied SICM to image collagen fibrils and showed the usefulness of the approach-retract scanning (ARS)/hopping mode for such samples with steep slopes. Comparison of SICM images with those obtained by AFM revealed that the ARS/hopping SICM mode can probe the surface topography of collagen fibrils and chromosomes at nanoscale resolution under liquid conditions. In addition, we successfully imaged cultured HeLa cells, with 15 μm in height by ARS/hopping SICM mode. Because SICM can obtain non-contact (or force-free) images, delicate cellular projections were visualized on the surface of the fixed cell. SICM imaging of live HeLa cells further demonstrated its applicability to study the morphological dynamics associated with biological processes on the time scale of minutes under liquid conditions. We further applied SICM for imaging the luminal surface of the trachea and succeeded in visualizing the surface of both ciliated and non-ciliated cells. These SICM images were comparable with those obtained by scanning electron microscopy. Although the dynamic mode of AFM provides better resolution than the ARS/hopping mode of SICM in some samples, only the latter can obtain contact-free images of samples with steep slopes, rendering it an important tool for observing live cells as well as unfixed or fixed soft samples with complicated shapes. Taken together, we demonstrate that SICM imaging, especially using an ARS/hopping mode, is a useful technique with unique capabilities for imaging the three-dimensional topography of a range of biological samples under physiologically relevant aqueous conditions. 相似文献