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101.
Hiromichi Arai Toshiya Kunisaki Yasuhiro Shimizu Tetsuro Seiyama 《Solid State Ionics》1986,20(4):241-248
The electrical conductivity of sintered specimens of (CeO2)1−x(CaO)x was investigated by employing a standard four-probe dc technique as a function of temperature between 400°C and 900°C, composition from 0.10x0.80, and oxygen partial pressure from 10−18 to 1 atm. The temperature and composition dependence of the emf have been carried out with a concentration cell. X-ray diffraction studies indicated that a cubic fluorite crystal remained in all specimens studied, although the solubility limit of CaO in CeO2 was assumed to lie close to 23 mol% from the change of the lattice constant. The magnitude of the conductivity decreased slightly with increase of the dopant concentrations up to x=0.50. The conductivity of these specimens was about 100 times larger than that of calcia-stabilized zirconia at 600°C with a smaller activation energies of 0.83–0.89 eV. With further increasing dopant concentrations, the magnitude of the conductivity was found to decrease remarkably. With an increase in the dopant concentration, the domain of primarily ionic conduction extended to a lower partial pressure. The conductivity of (CeO2)0.50(CaO)0.50 was found to be primarily ionic down to 10−12 atm even at 900°C. These results indicate that CaO-doped CeO2 may be more an attractive candidate for fuel cells and other applications. 相似文献
102.
Yoshihisa Kurosaki Dr. Toshiya Sagisaka Tomoo Matsushima Prof. Takashi Ubukata Prof. Yasushi Yokoyama 《Chemphyschem》2020,21(13):1375-1383
A chiral and thermally irreversible photochromic fulgide derivative incorporating an (R)-binaphthol unit in its acid anhydride moiety was used for the photoswitching of the pitch length of cholesteric liquid crystals. Since the absorption maximum wavelengths of both thermally stable photoisomers are nearly in the UV region (quasi-stealth photochromism), it can be exposed to visible light without inducing photochromic reactions. Therefore, when the photoswitching molecule is added to a permanent cholesteric liquid crystal whose reflection light wavelength is in the visible region, the UV light-induced photochromic reaction of the photoswitching molecule changes the wavelength of the reflection light in the visible light region. We have succeeded in regulating the color of cholesteric liquid crystalline cells between red and blue upon UV light irradiation. Attempts to introduce this system in polymer dispersed cholesteric liquid crystals are also described. 相似文献
103.
Zbynek Prokop Dr. Yukari Sato Dr. Jan Brezovsky Tomas Mozga Radka Chaloupkova Dr. Tana Koudelakova Petr Jerabek Veronika Stepankova Ryo Natsume Dr. Jan G. E. van Leeuwen Dick B. Janssen Prof. Jan Florian Dr. Yuji Nagata Dr. Toshiya Senda Dr. Jiri Damborsky Prof. 《Angewandte Chemie (International ed. in English)》2010,49(35):6111-6115
104.
105.
We propose a method for reconstructing a complex wavefront from a single-shot in-line digital hologram with a spatial radial carrier. In the proposed method, the spatial radial carrier is generated by a point source that is located in front of an image sensor, as close as possible to the sensor with the condition that the Nyquist limit is not exceeded. A signal processing method employed for elimination of the zeroth-order and conjugate wave components is presented. Computer simulations and optical experiments are performed to verify the proposed method. 相似文献
106.
Okubo S Okazaki T Hirose-Takai K Suenaga K Okada S Bandow S Iijima S 《Journal of the American Chemical Society》2010,132(43):15252-15258
The molecular orientation of ellipsoidal C(70) in single-walled carbon nanotubes (SWCNTs) depends on the tube diameter (d(t)). Photoluminescence (PL) studies reveal that the fullerene encapsulation effects on the optical transition energy of SWCNTs are significantly different for C(70) and C(60) at d(t) = 1.405-1.431 nm. This indicates that the transition from the "lying" alignment to the "standing" alignment occurs at d(t) ≈ 1.41 nm and the electronic states of SWCNTs are very sensitive to the interspacing between the encapsulated molecules and the SWCNTs. The present findings suggest that the electronic structure of SWCNTs is tunable not only by alternating the encapsulated molecules but also by controlling their molecular orientations, thus paving the way for development of novel SWCNT-based devices. 相似文献
107.
Ichikawa Y Okumura K Matsuda Y Hasegawa T Nakamura M Fujimoto A Masuda T Nakano K Kotsuki H 《Organic & biomolecular chemistry》2012,10(3):614-622
An efficient synthetic method for stereoselective construction of asymmetric quaternary carbon stereocenters, bearing nitrogen in the form of Boc-protected allyl amines, has been developed. This methodology is employed in the synthesis of marine alkaloids, manzacidin A and C. 相似文献
108.
Reported here is the preparation and property of 2D coordination networks composed of rodlike ligands with ethylene glycol side chains (1). Two 2D coordination networks, [[Co(1)2(H2O)2](NO3)2.1.5H2O]n and [[Ni(1)2(H(2)O)2](NO3)2.1.5H2O]n, have been synthesized and characterized by single-crystal X-ray diffraction, TG, DSC, UV-vis spectroscopy, and magnetic measurements. The structural analyses clarified that infinite 1D hydrogen-bond arrays composed of ethylene glycol chains contribute to the stabilization of 2D coordination frameworks, keeping the environment of substitution-active metal sites unchanged. They are more stable than a similar square-grid coordination network that does not possess an ethylene glycol chain on the ligand. We also succeeded in the direct observation of a reversible apical-ligand-exchange reaction at the cobalt(II) and nickel(II) ions in a single-crystal-to-single-crystal fashion because of the considerable stability as well as moderate flexibility of the framework. The cobalt-containing coordination network crystal showed chromic behavior depending on temperatures. Crystallographic and spectroscopic studies revealed that the color change of the crystal was attributed to the ligand-exchange process between H2O and a NO3 anion on the cobalt metal. Magnetic measurements indicated weak antiferromagnetic nearest-neighbor spin coupling between cobalt(II) ions. 相似文献
109.
Yoshida N Abe Y Shigeta H Nakajima A Ohsaki H Hashimoto K Watanabe T 《Journal of the American Chemical Society》2006,128(3):743-747
Flat films of methyl methacrylate-fluoroalkyl methacrylate copolymers were prepared, and their hydrophobicity was investigated. It was revealed that the F concentration directly affects the static hydrophobicity on the flat polymer surface in a systematic manner. Furthermore, the sliding behavior of a water droplet on these surfaces depends on the static hydrophobicity; the sliding motion changes from constant velocity to constant acceleration with an increase in the water contact angle. 相似文献
110.
Toshiya Uozumi Tatsuya Toneri Kazuo Soga Takeshi Shiono 《Macromolecular rapid communications》1997,18(1):9-15
Two kinds of SiO2-supported Cp*TiCl3 (Cp* = η5-1,2,3,4,5-pentamethylcyclopentadienyl) catalysts were prepared, using SiO2 modified with 3-aminopropyltrimethoxysilane (N SiO2) and the ordinary SiO2 as the carrier. The copolymerization of ethylene and 1-octene was conducted over them combined with methylaluminoxane (MAO) as cocatalyst. From a detailed analysis of the produced copolymers, it was found that the N SiO2 supported Cp*TiCl3 catalyst gives poly(ethylene-co-1-octene) with a higher content of 1-octene and a narrower molar mass distribution as well as a narrower chemical composition. 相似文献