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91.
Takumi Watanabe Yoichi Kamihara Masahiro Hirano Hideo Hosono 《Journal of solid state chemistry》2008,181(8):2117-2120
Rietveld analysis of the powder X-ray diffraction of a new layered oxyarsenide, LaNiOAs, which was synthesized by solid-state reactions, revealed that LaNiOAs belongs to the tetragonal ZrCuSiAs-type structure (P4/nmm) and is composed of alternating stacks of La-O and Ni-As layers. The electrical and magnetic measurements demonstrated that LaNiOAs exhibits a superconducting transition at 2.4 K, and above this, LaNiOAs shows metallic conduction and Pauli paramagnetism. The diamagnetic susceptibility measured at 1.8 K corresponded to ∼20% of perfect diamagnetic susceptibility, substantiating that LaNiOAs is a bulk superconductor. 相似文献
92.
Kitazaki T Ichikawa T Tasaka A Hosono H Matsushita Y Hayashi R Okonogi K Itoh K 《Chemical & pharmaceutical bulletin》2000,48(12):1935-1946
New optically active antifungal azoles, N-14-(azolyl)phenyl]- and N-14-(azolylmethyl)phenyl]-N'-[(IR,2R)-2(2,4-difluorophenyl)-2-hydroxy-1-methyl-3-(IH-1,2,4-triazol-1-yl)propyllazolones (1, 2, 3), were prepared in a stereocontrolled manner. Compounds 1-3 showed strong antifungal activity against Candida albicans in vitro. Among them, the imidazolidinones 3 showed a broad antifungal spectrum in vitro as well as potent in vivo activity against candidiasis and aspergillosis in mice. The imidazolidinones (3i, j, k) having 1H-1,2,3-triazol-1-yl, 2H-2-tetrazolyl and IH-1-tetrazolyl moieties were found to exert strong protective effect against aspergillosis. 相似文献
93.
Sakaushi K Nickerl G Wisser FM Nishio-Hamane D Hosono E Zhou H Kaskel S Eckert J 《Angewandte Chemie (International ed. in English)》2012,51(31):7850-7854
Packed with energy: Amorphous covalent triazine-based frameworks were used as a cathode material, with the aim of developing an energy storage principle that can deliver a 2-3 times higher specific energy than current batteries with a high rate capability. The material undergoes a unique Faradaic reaction, as it can be present in both a p-doped and an n-doped state (see picture). 相似文献
94.
The effect of oxygen diffusion from the atmosphere on tin depth profile in the bottom face of a soda-lime-silica float glass at temperatures above Tg was investigated. The heat treatment was performed in 18O2/N2 and argon (Ar) atmospheres. The significant diffusion of tin to the surface was observed for the glass heat-treated in 18O2/N2 atmosphere, resulting in the formation of a tin-enriched layer near the surface region. It was found that the tin was supplied from the region shallower than the ‘hump’ which is commonly observed in the tin profile of a commercial soda-lime-silica float glass. No significant change in the tin depth profile was observed for the glass heat-treated in Ar atmosphere. These results indicate that 18O diffusion into the glass, which causes the change in chemical state of tin from Sn2+ to Sn4+, induces the significant diffusion of tin. Furthermore, the precipitation of crystalline SnO2 particles with a diameter of ∼1 nm was clearly recognized in the tin-enriched layer. This fact indicates that a phase separation was induced by the oxygen diffusion into the glass. Consequently, Sn2+ may be supplied to the surface in order to compensate for the marked decrease in Sn2+ concentration in the glass system. The significant diffusion of tin to the surface was suppressed by increasing the iron content in the glass. This suppression was ascribed to the increase in Sn4+ concentration as a result of the redox reaction between tin and iron because the diffusion coefficient of Sn4+ is much smaller than that of Sn2+. 相似文献
95.
Paola Zimmermann Crocomo Dr. Masato Okazaki Takumi Hosono Prof. Dr. Satoshi Minakata Prof. Dr. Youhei Takeda Prof. Dr. Przemyslaw Data 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(43):e202200826
Previous work has reported the synthesis of donor–acceptor–donor molecules based on dibenzophenazine acceptor group, presenting thermally activated delayed fluorescent (TADF) properties and their application in the assembly of highly efficient electroluminescent devices. Herein, we focus on the characterisation of charge carrier species through UV-Vis-NIR spectroelectrochemical and potentiostatic EPR techniques, in addition to the investigation of electropolymerisation properties of some compounds depicted in this study. The promising electrochromic features of both small molecules and conjugated polymers led to the assembly and investigation of electrochromic devices, evidencing the materials’ versatility, applied in such different approaches as electrochromic windows and electroluminescent devices. Furthermore, the assembled OLEDs provided high efficiencies, with small roll-off, EQEs up to 20.5 % and luminance values up to 85 000 cd/m2. 相似文献
96.
A series of tetragonal ThCr(2)Si(2)-type compounds, R(2)O(2)Bi (R = rare earth or Y), are synthesized in which an unusual Bi(2-) anion forms a square net layer that is sandwiched between (R(2)O(2))(2+) fluorite layers. Two-dimensional (2D) electronic bands around the Fermi energy are predominantly composed of 6p(x)6p(y) orbitals in the Bi(2-) square net, which contains a positive hole per Bi(2-) ion. The decrease in the size of the square net caused by reducing the size of the R ion enhances the electrical conductivity because of the hole, resulting in a "chemical pressure"-induced metal-insulator transition. 相似文献
97.
Takao Kokubu Yuya Oaki Dr. Hiroaki Uchiyama Dr. Eiji Hosono Dr. Haoshen Zhou Dr. Hiroaki Imai Prof. Dr. 《化学:亚洲杂志》2010,5(4):792-798
We have synthesized spinel type cobalt‐doped LiMn2O4 (LiMn2?yCoyO4, 0≤y≤0.367), a cathode material for a lithium‐ion battery, with hierarchical sponge structures via the cobalt‐doped MnCO3 (Mn1‐xCoxCO3, 0≤x≤0.204) formed in an agar gel matrix. Biomimetic crystal growth in the gel matrix facilitates the generation of both an homogeneous solid solution and the hierarchical structures under ambient condition. The controlled composition and the hierarchical structure of the cobalt‐doped MnCO3 precursor played an important role in the formation of the cobalt‐doped LiMn2O4. The charge–discharge reversible stability of the resultant LiMn1.947Co0.053O4 was improved to ca. 12 % loss of the discharge capacity after 100 cycles, while pure LiMn2O4 showed 24 % loss of the discharge capacity after 100 cycles. The parallel control of the hierarchical structure and the composition in the precursor material through a biomimetic approach, promises the development of functional materials under mild conditions. 相似文献
98.
We report 31P and 139La NMR studies of (La0.87Ca0.13)FePO, which is a family member of the recently discovered superconductor LaFeAs(O1-xFx). In the normal state, Knight shift and nuclear spin-lattice relaxation rate divided by T (1/T1T) show that a Fermi-liquid state with moderate ferromagnetic fluctuations emerges below 30 K. From 1/T1T of 31P and 139La, a quasi-two- dimensional electronic structure is suggested, in which the FeP layer is more conductive than the LaO layer. In the superconducting (SC) state, although a clear Meissner signal was observed, 1/T1T increases below Tc, in contrast to a decrease of 1/T1T due to the opening of a SC gap, suggesting that novel low-energy spin dynamics develop in the SC state. 相似文献
99.
N. Matsuoka K. Hatanaka M. Fujiwara Y. Fujita T. Saito K. Hosono A. Shimizu M. Kondo F. Ohtani H. Sakaguchi A. Goto N. Nakanishi Y. Toba 《Nuclear Physics A》1982,373(3):377-396
Differential cross sections of 3He elastic scatterings and (3He, d) reactions have been measured at 90 MeV for 28Si, 54Fe, 58Ni, 90Zr and 124Sn. From the optical-model analysis of the elastic scattering, both shallow () and deep () potentials of 3He were obtained. The shallow potentials correspond to the ones which were determined uniquely from other measurements extended to more backward angles. The (3He, d) reactions have been analyzed with the DWBA using the shallow and deep potentials for 3He. The calculations using the deep potentials reproduced the data well, but those using the shallow ones did not. The contributions from the nuclear interior were investigated through the radial cutoff in the DWBA. The calculations using the shallow potentials reproduced the data well when the radial cutoffs were introduced. The effects of the radial cutoff were very small when the deep potentials were used. It was found that a much greater reduction of the contributions from the nuclear interior was needed when the shallow potentials were used in the DWBA calculations. 相似文献
100.
Tibor Bisztriczky Kiyoshi Hosono Gyula Károlyi Masatsugu Urabe 《Periodica Mathematica Hungarica》2004,49(2):1-8
Let P denote a finite set of points, in general position in the plane. In this note we study conditions which guarantee that P contains the vertex set of a convex polygon that has exactly k points of P in its interior. 相似文献