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排序方式: 共有291条查询结果,搜索用时 15 毫秒
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Hitoshi Osawa Toshiaki IwazumiHiroko Tokoro Shin-ichi OhkoshiKazuhito Hashimoto Hironobu ShojiEiju Hirai Tetsuya NakamuraSusumu Nanao Yasuhito Isozumi 《Solid State Communications》2003,125(5):237-241
The thermal phase transition of RbMnFe(CN)6 has been observed by Mn and Fe 3p-1s X-ray emission spectroscopy (XES) and 1s X-ray absorption spectroscopy (XAS). The thermal variations of the spin states and the valences of Mn and Fe were determined to be Mn2+(S=5/2)-NC-Fe3+(S=1/2) for the high-temperature (HT) phase and Mn3+(S=2)-NC-Fe2+(S=0) for the low-temperature (LT) phase. These transitions are thus caused by charge transfer between Mn and Fe. The temperature dependences of Mn and Fe 3p-1s XES and 1s XAS were observed as the composition of the spectra of the HT and LT phases. The ratios of the HT component in each spectrum show good agreement with the thermal transition curves observed with magnetic susceptibility measurements. 相似文献
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Xie Jian Imanishi Nobuyuki Hirano Atsushi Takeda Yashuo Yamamoto Osamu Zhao Xin-Bing Cao Gao-Shao 《Journal of Solid State Electrochemistry》2011,15(9):2031-2039
Ag and Ag2O thin films have been prepared by radio frequency magnetron sputtering on Cu substrates and have been characterized by X-ray
diffraction, scanning electron microscope and atomic force microscope. The electrochemical performance of the thin films has
been studied by galvanostatic cycling and cyclic voltammetry. The potential dependence of Li-ion chemical diffusion coefficients,
[(D)\tilde]\textLi {\widetilde{D}_{\text{Li}}} , of the films has been determined by galvanostatic intermittent titration technique and electrochemical impedance spectroscopy.
It is found that Li-ion chemical diffusion coefficients of the Ag film range from 10−16 to 3 × 10−14 cm2 s−1. The Ag/Li2O composite that is formed from Ag2O after the first cycle exhibits higher
[(D)\tilde]\textLi {\widetilde{D}_{\text{Li}}} values than the Ag film, especially at a low Li-intercalation content. The phase transitions in the two-phase region cause
a significant decrease of chemical diffusion coefficients. 相似文献
26.
Masahiko Ogura Norikazu Nakatani Norisuke Yamaji Makoto Imai Akio Itoh Nobutsugu Imanishi 《Radiation Physics and Chemistry》1997,49(6):645-649
We have studied effects of added elements as well as defects on trap-sites of hydrogen in metals. For the purpose, we observed depth profiles and thermal behaviors of hydrogen implanted into Al-1.5 at.% Si alloy samples in an implantation-temperature range of liquid nitrogen temperature (LNT) to 373 K at different doses. The results were compared with those for pure aluminum samples. It was found that hydrogen is trapped as molecules in grain boundaries of Al/Si. 相似文献
27.
To develop a novel nucleoside analogue for the effective recognition of CG interruption in a homopurine-homopyrimidine tract of double-stranded DNA (dsDNA), we succeeded in the synthesis of a triplex-forming oligonucleotide (TFO) containing a novel 2′,4′-BNA (QB) bearing 1-isoquinolone as a nucleobase, and the triplex-forming ability and sequence-selectivity of the TFO (TFO-QB) were examined. On melting temperature (Tm) measurements, it was found that the TFO-QB formed a stable triplex DNA in a highly sequence-selective manner under near physiological conditions. 相似文献
28.
Zirconia based oxide ion conductors for solid oxide fuel cells 总被引:2,自引:0,他引:2
O. Yamamoto Y. Arachi H. Sakai Y. Takeda N. Imanishi Y. Mizutani M. Kawai Y. Nakamura 《Ionics》1998,4(5-6):403-408
The electrical conductivity in the ZrO2-Ln2O3 and ZrO2-MO2-Ln2O3(M = Hf, Ce, Ln = lanthanides) systems has been examined.The highest conductivity of 0.3 S/cm at 1000 °C was found in the
ZrO2-Sc2O3 system. The addition of MO2 into the ZrO2-Ln2O3(Ln = Sc, Y, Yb) systems showed the conductivity decreasing. The conduction mechanism in the zirconia based oxide ion conductors
was discussed in view of the dopant ionic radius. The aging effect of the conductivity in the ZrO2-Ln2O3 systems has been measured in a temperature rang 800–1000 °C. ZrO2 with a high content of Ln2O3 showed no significant conductivity degradation.
Paper presented at the 97th Xiangshan Science Conference on New Solid State Fuel Cells, Xiangshan, Beijing, China, June 14–17,
1998. 相似文献
29.
Coupled channel calculations for (d, p) reactions were performed in which a strong coupling between the d and p channels was assumed. Reactions investigated were 16O(d, p) 17O(2s) and 40Ca(d, p) 41Ca(2p) at Ed =10.5 MeV and the related (d, d) and (p, p) scattering processes. The nonorthogonality of the d- and p-channels were taken into account. The results of these calculations are presented and are compared with the coupled channel calculations neglecting the channel nonorthogonality and also compared with the DWBA and optical model calculations. 相似文献
30.
Imanishi A Suzuki H Murakoshi K Nakato Y 《The journal of physical chemistry. B》2006,110(42):21050-21054
Dye-sensitized photocurrents at (100)-, (001)-, and (110)-cut TiO(2) rutile surfaces were increased by photoetching of TiO(2), but the increasing ratio strongly depended on the cut crystal faces and the illumination intensity for the photoetching. For the (110)-cut surface, the photocurrent increase was moderately large and in proportion to the increase in the surface area of TiO(2) induced by the photoetching, irrespective of the illumination intensity for the photoetching. On the other hand, the photocurrent increases for the (001)- and (100)-cut surfaces, especially that for the (001)-cut surface, were prominent and largely exceeded the increases in the surface area. The results were explained by taking into account the following factors: (1) The (001)- and (100)-cut surfaces were thermodynamically unstable in contrast to the (110)-cut surface and had thicker inactive surface layers (or higher densities of surface defects), produced by surface reconstruction during heat treatment of TiO(2) at 550 degrees C in a hydrogen atmosphere for getting n-type semiconductivity. (2) Photoetching not only increased the surface area through formation of nanoholes and grooves at the surface but also effectively removed the thin inactive surface layers (or surface defects). 相似文献