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21.
We found that La(2)Sb with a layered structure composed of alternate stacking of La square nets and LaSb layers exhibits bulk superconductivity with a critical temperature of 5.3 K. This suggests that the presence of the square net with strong La-La metal bonding is essential for the emergence of superconductivity. 相似文献
22.
Kiyoshi Hosono 《Discrete Mathematics》2011,(17):1886
Let P be a finite set of points in general position in the plane. We evaluate the ratio between the maximum area of an empty triangle of P and the area of the convex hull of P. 相似文献
23.
Science China Mathematics - We study conditions of Hörmander’s L2-estimate and the Ohsawa-Takegoshi extension theorem. Introducing a twisted version of the Hörmander-type condition,... 相似文献
24.
Mirror Symmetry, Picard-Fuchs equations and instanton corrected Yukawa couplings are discussed within the framework of toric geometry. It allows to establish mirror symmetry of Calabi-Yau spaces for which the mirror manifold had been unavailable in previous constructions. Mirror maps and Yukawa couplings are explicitly given for several examples with two and three moduli.On leave of absence from Dept. of Math., Toyama Univ., Toyama 930, Japan (address after Sept. 1, 1993)Address after Oct. 1, 1993: Dept. of Math., Harvard Univ., Cambridge, MA 02138, USA. after April 1, 1994: CERN, Theory Division, CH-1211 Geneva 23, Switzerland 相似文献
25.
The stress-concentration factor for keyways is obtained by the electroplating method of strain analysis which was recently developed in Japan. The stresses in keyways are examined under most practical conditions. The shaft to be examined is set in a boss and fixed with a key so that the torque is wholly transmitted to the test piece through the key. To obtain the limit value for a shaft twisted only through a key, the fitting is devised so as to minimize the surface friction at the fitted portion. The results are compared to those reported previously by other authors in which local effects of the key are ignored. 相似文献
26.
Y Sasaki M Matsui H Fujita M Hosono M Taguchi K Suzuki S Sakurada T Sato T Sakurada K Kisara 《Chemical & pharmaceutical bulletin》1985,33(4):1528-1536
27.
K. Nisimura H. Shimizu K. Imai T. Ichihara N. Matsuoka K. Hatanaka H. Sakai T. Saito K. Hosono M. Kondo A. Okihana 《Nuclear Physics A》1985,432(2):378-388
The differential cross section and the vector and tensor analyzing powers Ay, Axx, Ayy and Axz were measured for the d-4He elastic scattering at 56 MeV. The measurement of Axz was performed using a deuteron beam polarized in the horizontal plane. An optical-model analysis of the experimental data was carried out. The magnitude of the tensor analyzing powers could not be reproduced without the tensor potential. By including the TR type tensor potential, the optical-model calculations give a reasonable reproduction of the experimental data at θc.m. < 120°. The obtained TR tensor potential was much stronger than that predicted by the folding model. The strength of the real TR potential was roughly in accordance with that obtained from the optical-model analysis of d-4He elastic scattering at 20.2 MeV. 相似文献
28.
Jiazhen Wu Jiang Li Yutong Gong Masaaki Kitano Takeshi Inoshita Hideo Hosono 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(3):835-839
Electrides loaded with transition‐metal (TM) nanoparticles have recently attracted attention as emerging materials for catalytic NH3 synthesis. However, they suffer from disadvantages associated with the growth and aggregation of nanoparticles. TM‐containing intermetallic electrides appear to be promising catalysts with the advantages of both electrides and transition metals in a single phase. LaRuSi is reported here to be an intermetallic electride with superior activity for NH3 synthesis, and direct evidence is provided supporting its electride‐character‐induced catalytic performance. The discussion is made mainly based on the contrasting synthesis rates over the isostructural compounds LaRuSi, CaRuSi, and LaRu2Si2, and the N2 isotope‐exchange reactions over these compounds. Lattice hydride ions, which can reversibly exchange with anionic electrons, are shown to be indispensable in the promotion of NHx formation. The mechanism derived from the present findings provides new guidelines for NH3 synthesis. 相似文献
29.
A systematic investigation on nanocrystalline LiCoO2 has been carried out using Raman spectroscopy. We synthesized nanocrystalline LiCoO2 (ca. 20-50 nm) through a combination of rapid thermal annealing at various annealing temperatures and a sol-gel method assisted with a triblock copolymer surfactant. Powder X-ray diffraction measurements revealed the formation of LiCoO2. The crystallite size of LiCoO2 from the Scherrer equation strongly depended on the annealing temperature. The crystallite size was confirmed by SEM and TEM measurements. Raman shifts of the A1g and Eg modes for nanocrystalline LiCoO2 exhibited a broadening and a frequency shift according to the crystallite size. While the frequency shift could be ascribed to a structural strain at the surface, the broadening was due to the phonon confinement effect produced by narrow crystal boundaries. 相似文献
30.
Koichi Kajihara Taisuke Miura Hayato Kamioka Akira Aiba Motoko Uramoto Yukihiro Morimoto Masahiro Hirano Linards Skuja Hideo Hosono 《Journal of Non》2008,354(2-9):224-232
This article briefly summarizes the diffusion and reactions of interstitial oxygen species in amorphous SiO2 (a-SiO2). The most common form of interstitial oxygen species is oxygen molecule (O2), which is sensitively detectable via its characteristic infrared photoluminescence (PL) at 1272 nm. The PL observation of interstitial O2 provides key data to verify various processes related to interstitial oxygen species: the dominant role of interstitial O2 in long-range oxygen transport in a-SiO2; formation of the Frenkel defect pair (Si–Si bond and interstitial oxygen atom, O0) by dense electronic excitation; efficient photolysis of interstitial O2 into O0 with F2 laser light (λ = 157 nm, hν = 7.9 eV); and creation of interstitial ozone molecule via reaction of interstitial O2 with photogenerated O0. The efficient formation of interstitial O0 by F2 laser photolysis makes it possible to investigate the mobility, optical absorption, and chemical reactions of interstitial O0. The observed properties of O0 are consistent with the model that O0 takes the configuration of Si–O–O–Si bond. Interstitial O2 and O0 react with dangling bonds, oxygen vacancies, and chloride groups in a-SiO2. Reactions of interstitial O2 and O0 with mobile interstitial hydrogen species produce interstitial water molecules and hydroperoxy radicals. Interstitial hydroxyl radicals are formed by F2 laser photolysis of interstitial water molecules. 相似文献