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121.
122.
Kunimitsu Kataoka Yasuhiko Takahashi Norihito Kijima Hiroshi Hayakawa Junji Akimoto Ken-ichi Ohshima 《Solid State Ionics》2009,180(6-8):631-635
Single crystals of Li4 + xTi5O12 were prepared by means of electrochemical Li-ion intercalation technique using parent Li4Ti5O12 single crystals. The obtained Li4 + xTi5O12 (x = 1.35) crystallizes in the cubic spinel-related type structure, space group Fd3?m, and lattice parameters of a = 8.346(2) Å and V = 581.3(5) Å3 and Z = 8. The Li-ion intercalated sites were successfully determined to be both the 8a and 16c sites by using the difference Fourier synthesis map. The structure was determined by single-crystal X-ray structure analysis and refined to the conventional value of R = 3.7% for 132 independent observed reflections. The chemical composition has been determined to be Li5.35Ti5O12 from the result of site-population refinements. In addition, theoretical electron density distributions and total energy were calculated for three postulated compounds of “Li4.5Ti4.5O12” and “Li4.5 + xTi4.5O12” with x = 1.5 and 3.0. 相似文献
123.
Junji Awaka Norihito Kijima Hiroshi Hayakawa Junji Akimoto 《Journal of solid state chemistry》2009,182(8):2046-2052
We have successfully synthesized a high-purity polycrystalline sample of tetragonal Li7La3Zr2O12. Single crystals have been also grown by a flux method. The single-crystal X-ray diffraction analysis verifies that tetragonal Li7La3Zr2O12 has the garnet-related type structure with a space group of I41/acd (no. 142). The lattice constants are a=13.134(4) Å and c=12.663(8) Å. The garnet-type framework structure is composed of two types of dodecahedral LaO8 and octahedral ZrO6. Li atoms occupy three crystallographic sites in the interstices of this framework structure, where Li(1), Li(2), and Li(3) atoms are located at the tetrahedral 8a site and the distorted octahedral 16f and 32g sites, respectively. The structure is also investigated by the Rietveld method with X-ray and neutron powder diffraction data. These diffraction patterns are identified as the tetragonal Li7La3Zr2O12 structure determined from the single-crystal data. The present tetragonal Li7La3Zr2O12 sample exhibits a bulk Li-ion conductivity of σb=1.63×10−6 S cm−1 and grain-boundary Li-ion conductivity of σgb=5.59×10−7 S cm−1 at 300 K. The activation energy is estimated to be Ea=0.54 eV in the temperature range of 300–560 K. 相似文献
124.
Heisuke Ishino Shigeto Iwai Shunji Iwamoto Tsuneo Okumura Takayoshi Kobayashi Eiji Tokunaga 《Optical Review》2010,17(3):337-340
Nonlinear confocal absorption microspectroscopy of single nanocrystals at low temperatures was introduced in the study of
perylene nanocrystals. By the stationary pump-probe method, single nanocrystals were photoexcited into metastable excited
states, and difference absorption spectra due to excited-state absorption and ground-state depletion were simultaneously recorded
using a multichannel lock-in amplifier. It was revealed that the free Frenkel exciton band for single perylene nanocrystals
is broader in width than that for the bulk crystal at low temperatures, suggesting that the exciton band is inhomogeneously
broadened even for single perylene nanocrystals. 相似文献
125.
Shin-ichi Tokunaga 《Graphs and Combinatorics》1999,15(2):239-247
Let P be a set of finite points in the plane in general position, and let x be a point which is not contained in any of the lines passing through at least two points of P. A line l is said to be a k-bisector if both of the two closed half-planes determined by l contain at least k points of P. We show that if any line passing through x is a -bisector and does not contain two or more points of P, then there exist three points P
1, P
2, P
3 of P such that ΔP
1
P
2
P
3 contains x and does not contain points of P in its interior, and such that each of the lines passing through two of them is a -bisector.
Received: October 16, 1995 / Revised: October 16, 1996 相似文献
126.
M. Hagiwara K. Katsumata H. Yamaguchi M. Tokunaga I. Yamada M. Gross P. Goy 《International Journal of Infrared and Millimeter Waves》1999,20(4):617-622
Antiferromagnetic resonance (AFMR) measurements on a well characterized single crystal sample of MnF2 have been performed using various kinds of millimeter and submillimeter sources up to 570 GHz and a superconducting magnet up to 20 T. All the AFMR modes predicted from the theory have been observed. We report a complete frequency-field chart for these AFMR modes. 相似文献
127.
Naotoshi Nakashima Takeshi Tokunaga Yuko Nonaka Takashi Nakanishi Hiroto Murakami Takamasa Sagara 《Angewandte Chemie (International ed. in English)》1998,37(19):2671-2673
Two reversible one-electron transfers are observed for an electrode device made from C60 and an artificial lipid (see schematic drawing). Cyclic voltammetric studies reveal that the redox couples are unchanged even after 50 cycles, thus indicating that the C60 radical monoanion and the C60 dianion generated in aqueous solution are very stable. 相似文献
128.
The fourth‒order finite difference method is combined with the vorticity–streamfunction formulation in generalized co‒ordinates. Direct numerical simulations are performed for channel flows with and without surface roughness at a Reynolds number of 104. The present results are in good agreement with those of the pseudospectral method with respect to the flow in a smooth channel. It is shown that the present method predicts well the precise change in the flow with the channel length and roughness height. The turbulence is generally weakened by the roughness. Laminarization is also accomplished under the appropriate condition. © 1997 John Wiley & Sons, Ltd. 相似文献
129.
130.