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161.
Orikasa Y Ina T Nakao T Mineshige A Amezawa K Oishi M Arai H Ogumi Z Uchimoto Y 《Physical chemistry chemical physics : PCCP》2011,13(37):16637-16643
The electrical conduction mechanism of mixed conductive perovskite oxides, La(0.6)Sr(0.4)Co(0.8)Fe(0.2)O(3-δ), for cathode materials of solid oxide fuel cells has been investigated from electronic structural changes during oxygen vacancy formation. La(0.6)Sr(0.4)Co(0.8)Fe(0.2)O(3-δ) was annealed under various oxygen partial pressures p(O(2))s at 1073 K and quenched. Iodometric titration indicated that the oxygen nonstoichiometry of La(0.6)Sr(0.4)Co(0.8)Fe(0.2)O(3-δ) depended on the annealing p(O(2)), with more oxygen vacancies introduced at lower than at higher p(O(2))s. X-Ray absorption spectroscopic measurements were performed at the O K-, Co L-, Fe L-, Co K-, and Fe K-edges. The valence states of the Co and Fe ions were investigated by the X-ray absorption near edge structure (XANES) at the Co and Fe L(III)-edges. While the Fe average valence was almost constant, the valence of the Co ions decreased with oxygen vacancy introduction. The O K-edge XANES spectra indicated that electrons were injected into the Co 3d/O 2p hybridization state with oxygen vacancy introduction. Both absorption edges at the Co and Fe K-edge XANES shifted towards lower energies with oxygen vacancy introduction. The shift at the Co K-edge resulted from the decrease in the Co average valence and that at the Fe K-edge appeared to be caused by changes in the coordination environment around the Fe ions. The total conductivity of La(0.6)Sr(0.4)Co(0.8)Fe(0.2)O(3-δ) decreased with decreasing p(O(2)), due to a decreasing hole concentration. 相似文献
162.
163.
Shugo Suzuki Shinìchi Higai Nobutada Nagai Kenji Nakao 《Molecular Crystals and Liquid Crystals》2013,570(1):587-592
Abstract We have studied theoretically the electronic structures of a hypothetical donor-type material, (PH4)3C60, and a hypothetical acceptor-type material, (ClO4)3C60 from first principles by using a full-potential linear-combination-of-atomic-orbitals method based on the density-functional theory within the local-density approximation. It is found that the charge transfer from the PH4 molecules to the C60 molecules is perfect while the charge transfer from the ClO4 molecules to the C60 molecules is not perfect. We compare the latter result with the electronic structures of two typical acceptor-type organic conductors, (TMTSF)2ClO4 and (TMTSF)2PF6, and discuss the differences. 相似文献
164.
Kiichi Kamimura Yuji Matsumoto Myo Than Oo Masato Nakao Yoshiharu Onuma 《Molecular Crystals and Liquid Crystals》2013,570(1):713-717
Abstract Carbon films were prepared by hot filament assisted sputtering. Pure argon was used as the sputtering gas. The substrate temperature was 600 °C and the filament temperature was about 2000 °C. Sample was inhomogeneous. Scanning electron microscope (SEM) and transmission electron microscope (TEM) images showed that some part of films consisted of carbon nano fibers (not hollow but solid). Amorphous and polycrystalline phases were also detected by these measurements. No tube structure was observed by high resolution TEM. The diameter of the fiber was 10–30 nm. 相似文献
165.
166.
T. A. W. Beale G. Beutier S. R. Bland A. Bombardi L. Bouchenoire O. Bun?u S. Di Matteo J. Fernández-Rodríguez J. E. Hamann-Borrero J. Herrero-Martín V. L. R. Jacques R. D. Johnson A. Juhin T. Matsumura C. Mazzoli A. M. Mulders H. Nakao J. Okamoto S. Partzsch A. J. Princep V. Scagnoli J. Strempfer C. Vecchini Y. Wakabayashi H. C. Walker D. Wermeille Y. Yamasaki 《The European physical journal. Special topics》2012,208(1):89-98
Resonant Elastic X-Ray Scattering (REXS) has played a fundamental role in understanding electronic properties and in revealing hidden order, local symmetries and exotic states realized in correlated solids. This article reports on some of the relevant scientific contributions and technical advances over the last 20 years, by providing a list of related publications produced by various groups all around the world. The given perspective is that of a group of young scientists involved at various times in the investigation of the beauty of electronic ordering by the REXS technique. 相似文献
167.
Mohapatra D Nakao M Nishida S Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Asano Y Aulchenko V Aushev T Bahinipati S Bakich AM Balagura V Barbero M Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Drutskoy A Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Gokhroo G Golob B Gorisek A Ha HC Haba J Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L 《Physical review letters》2006,96(22):221601
We report the observation of the flavor-changing neutral current process b-->dgamma using a sample of 386 x 106 B meson pairs accumulated by the Belle detector at the KEKB e+e- collider. We measure branching fractions for the exclusive modes B--->rho-gamma, B0rho0gamma, and B0omegagamma. Assuming that these three modes are related by isospin, we find B(B-->(rho,gamma)gamma)=[Formula: See Text] with a significance of 5.1sigma. This result is used to determine the ratio of Cabibbo-Kobayashi-Maskawa matrix elements /Vtd/Vts/ to be [Formula: See Text]. 相似文献
168.
An effective white-noise Langevin equation is derived that describes long-time phase dynamics of a limit-cycle oscillator driven by weak stationary colored noise. Effective drift and diffusion coefficients are given in terms of the phase sensitivity of the oscillator and the correlation function of the noise, and are explicitly calculated for oscillators with sinusoidal phase sensitivity functions driven by two typical colored Gaussian processes. The results are verified by numerical simulations using several types of stochastic or chaotic noise. The drift and diffusion coefficients of oscillators driven by chaotic noise exhibit anomalous dependence on the oscillator frequency, reflecting the peculiar power spectrum of the chaotic noise. 相似文献
169.
We theoretically investigate the collective phase synchronization between interacting groups of globally coupled noisy identical phase oscillators exhibiting macroscopic rhythms. Using the phase reduction method, we derive coupled collective phase equations describing the macroscopic rhythms of the groups from microscopic Langevin phase equations of the individual oscillators via nonlinear Fokker-Planck equations. For sinusoidal microscopic coupling, we determine the type of the collective phase coupling function, i.e., whether the groups exhibit in-phase or antiphase synchronization. We show that the macroscopic rhythms can exhibit effective antiphase synchronization even if the microscopic phase coupling between the groups is in-phase, and vice versa. Moreover, near the onset of collective oscillations, we analytically obtain the collective phase coupling function using center-manifold and phase reductions of the nonlinear Fokker-Planck equations. 相似文献
170.
Y. Ichikawa T. Kubo N. Aoi V. Banerjee A. Chakrabarti N. Fukuda H. Iwasaki S. Kubono T. Motobayashi T. Nakabayashi T. Nakamura T. Nakao T. Okumura H. J. Ong T. K. Onishi D. Suzuki H. Suzuki M. K. Suzuki T. Teranishi K. N. Yamada H. Yamaguchi H. Sakurai 《The European Physical Journal A - Hadrons and Nuclei》2009,42(3):375-378
$ \beta$ -decay spectroscopy on a T z = - 2 proton-rich nucleus 24Si was performed. The decay scheme of 24Si was reconstructed by the $ \beta$ -delayed $ \gamma$ -ray and proton measurements. Two $ \beta$ branches to the bound 11 + and 12 + states in 24Al were observed for the first time. The observation of the allowed transition firmly established the spin-parity assignment for the 12 + states. The branching ratios to the 11 + and 12 + states were determined to be 31(4)% and 23.9(15)%, respectively. The branching ratios to three unbound states in 24Al including a new level at 6.735MeV were also determined for the first time. The level structure of 24Al was compared with its mirror nucleus 24Na . The Thomas-Ehrman shift on the 12 + state indicates s -wave dominance in the state as well as a characteristic behavior of the weakly bound s -wave proton in 24Al . 相似文献