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71.
Naoto Kitamura Takuya Hasegawa Yoshiharu Uchimoto Koji Amezawa Yasushi Idemoto 《Electrochimica acta》2011,(25):9453
LiNi0.5Mn0.5O2 was heat-treated under high oxygen-pressure and Ar-reducing conditions, and then the cathode properties, thermodynamic stability and average and local structures were investigated. From X-ray diffraction and ICP measurements, it was found that the pristine LiNi0.5Mn0.5O2 had a single phase of the layered rock-salt structure although the Ni content was slightly rich compared with the nominal one. These characteristics were kept even after the heat-treatments. Charge–discharge cycle tests clarified that the cycle performance of LiNi0.5Mn0.5O2 was improved by both the reducing and oxidizing treatments. From neutron diffraction and X-ray absorption fine structure measurements, the local distortion around the transition metal, especially Ni, was supposed to be one of the important factors to determine the cathode properties. It was also found that the sample with higher thermodynamic stability exhibited better capacity retention in the discharge–charge cycle tests. 相似文献
72.
Takuya Kitabatake Tetsuo Uchikoshi Fumio Munakata Yoshio Sakka Naoto Hirosaki 《Journal of the European Ceramic Society》2012,32(7):1365-1369
The compaction of a Eu-doped Ca-α-SiAlON phosphor powder was performed by electrophoretic deposition (EPD). The effect on the adhesion and optical properties of the silica precursor as both a binder of the powder and a filler of the air voids were evaluated. The adhesion of the silica impregnated composite film to the silica glass substrate was characterized by the tape test. The improvement of the external quantum efficiency was confirmed from the PL spectra measurement after the silica impregnation. The temperature dependence of the external quantum efficiency was also investigated in order to discuss the advantage of using the silica precursor as a binder for high-brightness LED applications. 相似文献
73.
74.
We focused on Sr-substituted CePO4—i. e., (Ce,Sr)PO4—with the monazite structure and synthesized the orthophosphates hydrothermally. As for the obtained products, we investigated the particle morphologies by SEM and electrical conduction properties by conductivity measurements. In order to estimate the crystal and electronic structures, neutron and synchrotron X-ray diffraction measurements were also carried out. As a result, it was found that (Ce,Sr)PO4 with a single phase of the monazite structure was successfully prepared by the hydrothermal method and the substitution amount of Sr was almost equal to the nominal one. It was also demonstrated that a powder morphology of the (Ce,Sr)PO4 depended on the synthetic conditions; i.e, concentrations of cation sources and pH of aqueous solution in the hydrothermal process. The Sr-substituted sample showed much higher conductivities than the unsubstituted one, in the same way as the (Ce,Sr)PO4 synthesized by other methods reported previously. 相似文献
75.
Summary
New AB2 and A2B monomers, bis(4-fluorophenyl)-4'-hydroxyphenylphosphine oxide and bis(4-hydroxyphenyl)-4'-fluorophenyl-phosphine oxide were
prepared and converted to corresponding hyperbranched poly(arylene ether phosphineoxide)s with hydroxyphenyl and fluorophenyl
end functional groups. While the dihydroxy monomer gave a low molecular weight polymer, the difluoro monomer produced a high
molecular weight hyperbranched polymer. The glass transition temperature of the obtained polymers was 266°C and 230°C, and
5% weight loss temperature was 491 °C and 391 °C, respectively. The fluorophenyl-terminated hyperbranched polymer was soluble
in CHCl3, but the hydroxyphenyl-terminated polymer was not soluble in CHCl3 even though it has lower molecular weight than the fluorophenyl-terminated
polymer, indicating that properties of the hyperbranched polymers markedly depend on end functional groups as well as their
molecular weight.
Received: 23 August 2000/Revised version: 19 October 2000/Accepted: 31 October 2000 相似文献
76.
77.
E Kakimoto 《Welding International》2013,27(8):614-619
Welding of collector pipes, flat heads, dished ends and connector pipes made with high temperature and creep-resistant steels is most often done through a combination of TIG and MMA processes. Progress in MAG techniques and the availability of high-quality welding consumables (solid wires) now also enables MAG welding of the above-mentioned connections. In order to prove the efficiency of such, the results of our own studies are presented in this article. The range of tests applied was similar to those used during standard qualification of welding technologies. Additionally, the economics of welding 16Mo3 steel butt joints using different combinations of welding processes was assessed and compared. 相似文献
78.
Hirotsugu Takizawa Naoto HazeKeisuke Okamoto Kyota UhedaTadashi Endo 《Materials Research Bulletin》2002,37(1):113-121
Iron-doped β-rhombohedral boron was synthesized by 28 GHz microwave irradiation on a powder mixture of iron and β-boron. β-Boron strongly absorbs 28 GHz microwaves, and this strong coupling with microwave energy can be used to promote a reaction with iron dopant. The powder mixture was heated to 1800°C within 2 min by microwave irradiation, resulting in the formation of β-rhombohedral boron interstitially doped with iron. The reaction proceeded rapidly without accompanying grain growth. The XRD analysis and the electrical conductivity measurements revealed successful incorporation of iron into two doping sites of β-boron. 相似文献
79.
It is shown that the absorption loss coefficient of the active layer for 1.48-μm bulk lasers is 66 cm-1 which is between 45 and 107 cm-1 for 1.3-μm bulk lasers and for 1.55-μm bulk lasers, respectively. It is also described that the absorption loss coefficient of the active layer for 1.48-μm multiple-quantum-well (MQW) lasers is 28 cm-1 which is about two-fifths of that for 1.48-μm bulk lasers. Therefore, the high slope efficiency of the 1.48-μm MQW lasers is attributed not only to the small optical confinement factor but also to the small absorption loss coefficient of the active layer 相似文献
80.
A novel logic family for low-voltage adiabatic logic, called forward body-bias MOS (FBMOS) dual rail logic, has been proposed. This technique uses forward body-bias effects to enable non-floating output levels during the entire data valid time without increased transistor count 相似文献