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81.
Shiro Kubuki Hitomi Masuda Koken Matsuda Kazuhiko Akiyama Ayuko Kitajo Shigeto Okada Péter Zsabka Zoltán Homonnay Ernõ Kuzmann Tetsuaki Nishida 《Hyperfine Interactions》2014,226(1-3):765-770
Charge-discharge capacity and cyclicity of lithium ion battery (LIB) was evaluated in which 15Li2O·10Fe2O3·xSnO2·5P2O5·(70–x)V2O5 glass (x?=?0 and 20 in mol%, abbreviated as xLFSPV) was used as a cathode. A local structure of xLFSPV glass before and after charging was investigated by 57Fe- and 119Sn-Mössbauer spectroscopies. 57Fe-Mössbauer spectrum of xLFSPV glass with ‘x’ of 20 was composed of a doublet with isomer shift (δ) of 0.35±0.02 mm s???1 and quadrupole splitting (Δ) of 0.88±0.03 mm s???1 due to distorted FeIIIO4 tetrahedra. 119Sn-Mössbauer spectrum of this glass consisted of a doublet with δ of 0.08±0.01 and Δ of 0.52±0.01 mms???1 due to distorted SnVIO6 octahedra. After discharging the battery from 4.5 to 1.0 V, larger δ of 0.40±0.03 mm s???1 and Δ of 0.94±0.04 mm s???1 were obtained, indicating that both iconicity of Fe-O bonds and local distortion of FeIIIO4 tetrahedra were increased. On the contrary, identical δ of 0.09±0.01 mm s???1 and Δ of 0.50±0.01 mm s???1 were observed in the 119Sn-Mössbauer spectrum of 20LFSPV glass after the discharge, indicating that chemical environment of SnIVO6 octahedra was not affected after the discharge. Charge-discharge curve of LIB containing 20LFSPV glass as a cathode active material recorded under the current density of 8.3 mA g???1 (0.011 mA cm???2) between 1.0 and 4.5 V showed a large initial charge capacity of 431.1 mAh g???1 and discharge capacity of 382.3 mAh g???1, respectively. These results indicate that 20LFSPV glass could be a new cathode active material for LIB. 相似文献
82.
Abstract A memory type PDLC has been prepared by sandwiching a mixture of two-frequency-addressing liquid crystals and acrylate monomers with a hydoroxy group between two glass substrates with ITO electrodes followed by UV irradiation. This PDLC can be electrically switched between a transparent state and a light scattering state, which are maintained over several months without electric fields. 相似文献
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85.
Hyoe Hatakeyama Ayako Hirogaki Hiroshi Matsumura Tatsuko Hatakeyama 《Journal of Thermal Analysis and Calorimetry》2013,114(3):1075-1082
Sodium ligninosulfonate (LS)-based polyurethane (PU) foams were prepared using three kinds of ethylene glycols, diethylene glycol, triethylene glycol or polyethylene glycol. Two kinds of industrial NaLS, acid-based and alkaline-based NaLS, were mixed with various ratios, and foaming reactions were controlled. Mixing, cream, and rise time were used as an index of foaming reaction. Mixing time was defined as the time interval from adding isocyanate to detection of evolved heat under stirring, cream time as the time interval from termination of stirring to starting of foaming, and rise time as the time interval from starting to completion of foaming. The above reaction time increased with increasing amount of acid base NaLS content in polyols. Apparent density, compression strength and compression modulus of PU foams linearly increased with reaction time. Thermal decomposition temperature was measured by thermogravimetry and glass transition temperature by differential scanning calorimetry. Glass transition temperature can be controlled in a temperature range from 310 to 390 K by changing the mixing rate of two kinds of LS and molecular mass of ethylene glycols. It was found that mechanical and thermal properties of PU foams are controllable through the foaming reaction rate using two kinds of industrial lignin. 相似文献
86.
Abstract Color centers in rutile-structured MgF2 single crystals irradiated at 20K/360K by reactor neutrons are investigated spectroscopically at LNT. Four different types of the F-F vacancy bond in MgF2 are possibly identified to the observed absorption bands as due to the F2 centers; instead of previous assignments, the 300nm band to the F2(D2h), the 325nm band to the F2(C1), the 355nm band to the F2(C2v), and the 400nm band to the F2(C2h) centers. 相似文献
87.
Naoyuki Masuda Osamu Yamamoto Masahiro Fujii Tetsuro Ohgami Ayako Moritomo Toru Kontani 《合成通讯》2013,43(17):2305-2316
Various N‐3‐alkylated thiazolidenesulfonamide derivatives were efficiently prepared by the direct endo‐selective alkylation of thiazolylsulfonamides. The effects of different bases and solvents were investigated, and the NaH–THF combination was found to be the most effective at conferring high yields and endo‐selectivity. 相似文献
88.
Ayako Yano Nobuyuki Akai Hiroshi Ishii Chikahiro Satoh Takayuki Hironiwa Keith R. Millington Munetaka Nakata 《Polymer Degradation and Stability》2013
Thermal oxidative degradation of additive-free polypropylene pellets heated isothermally in dry air at 150 and 180 °C (below and above the melting point of 163 °C) was investigated by multichannel Fourier-transform chemiluminescence spectroscopy. The initial peak wavelength of chemiluminescence emission at 490 nm remained constant during the early stages of thermal degradation, but new emissions developed with time in the red spectral region over an extended oxidation period. The time-dependent luminescence spectra were deconvoluted into three emission bands by least-squares fitting using Gaussian curves. We concluded that at least three groups of luminescent species (luminophores), having different conjugation lengths, were generated by thermal oxidation over extended periods and show luminescence around 490, 660, and 740 nm. 相似文献
89.
Kenji Okada Yuichiro Takamatsu Yasuaki Tokudome Atsushi Nakahira Masahide Takahashi 《Journal of Sol-Gel Science and Technology》2013,65(1):36-40
Synthesis of titanate nanotubes (TNTs) from sol–gel derived amorphous TiO2 thin films under moderate hydrothermal condition has been reported. TNTs from film possess a tubular morphology that is the same crystalline phase as one synthesized from TiO2 powder so far. TNTs obtained in this study are not entangled one another but oriented and isolated on the substrate. Growth of highly oriented TNTs is observed in micro grooves of amorphous TiO2 thin film. Their orientation is also maintained with the growth of TNTs. 相似文献
90.
Akemi Umeyama Chihiro Ohta Yukari Shino Minori Okada Yukari Nakamura Tatsuya Hamagaki Hiroshi Imagawa Masami Tanaka Aki Ishiyama Masato Iwatsuki Kazuhiko Otoguro Satoshi Ōmura Toshihiro Hashimoto 《Tetrahedron》2014
During the search for new antitrypanosomal drug leads, three new antitrypanosomal compounds, hexatenuins A–C (1–3), were isolated from the fruiting body of Hexagonia tenuis. 1 and 3 possessed an unusual malonate half-ester functional group at C-3 position, and 1 and 2 had a spirostructure in the side-chain. Their structures were elucidated using MS analyses, extensive 2D-heteronuclear NMR data interpretation. Compounds 1–3 showed in vitro antitrypanosomal activity against Trypanosoma brucei brucei with IC50 values of 0.57, 8.60 and 5.62 μg/ml, respectively. 相似文献