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161.
Naoki Toshima Keiichi Kanaka Makoto Komiyama Hidefumi Hirai 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10-11):1349-1366
Interactions between polystyrene and aluminum copper(I) chloride (AlCuCl4) were investigated by various spectroscopic measurements in order to elucidate the structure of polystyrene-AlCuCl4 complex in solution and the mechanism of water resistance of the complex as a carbon monoxide absorbent. The chemical shift (101 ppm) and half line width (145 Hz) of AlCuCl4 in benzene by 27Al-NMR suggest a dimer structure bridged by two chlorine atoms, which is almost identical with that of aluminum chloride. The coordination of benzene or other aromatic compounds to AlCuCl4 was confirmed by charge-transfer bands in UV and visible absorptions. The equilibrium constants (K) for complex formation of AlCuCl4 with various aromatic compounds were determined by 13C-NMR spectroscopy. In the case of AlCuCl4 and benzene in 1,2-dichloroethane, for example, K is 2.2 M ?1 at 303 K. For the polymer complex solution and 1,3-diphenyl-propane solution, strong charge-transfer bands have been observed in the wavelength region at about 380 to 500 nm, where no band is observed in benzene derivatives. This strong charge-transfer band is considered to be due to the strong interaction of AlCuCl4 with adjacent aromatic rings of polystyrene or 1,3-diphenylpropane of a chelate type, which, as a result, causes the water resistance of the present carbon monoxide absorbent system. 相似文献
162.
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164.
Takahito Itoh Keita Hirai Masashi Tamura Takahiro Uno Masataka Kubo Yuichi Aihara 《Journal of Solid State Electrochemistry》2010,14(12):2179-2189
Two different molecular weight hyperbranched polymers (HBP(L)-(PA)2 and HBP(H)-(PA)2) with two phosphonic acid groups as a functional group at the periphery and a low molecular weight hyperbranched polymer (HBP(L)-(PA)2-Ac) with both two phosphonic acid groups and an acryloyl group as a cross-linker at the periphery were successfully synthesized as thermally stable proton-conducting electrolytes. A cross-linked electrolyte membrane (CL-HBP(L)-(PA)2) was prepared by thermal polymerization of the HBP(L)-(PA)2-Ac using benzoyl peroxide. Ionic conductivities of the HBP(L)-(PA)2, the HBP(H)-(PA)2, and the CL-HBP(L)-(PA)2 under dry condition and their thermal properties were investigated, and also, the effect of the phosphonic acid group number on them was discussed. Ionic conductivities of the HBP(L)-(PA)2 and the HBP(H)-(PA)2 were found to be 1.5?×?10?5 S cm?1 at 150 °C and 3.6?×?10?6 S cm?1 at 143 °C, respectively, under dry condition, and showed the Vogel–Tamman–Fulcher type temperature dependence. The hyperbranched polymers and the cross-linked electrolyte membrane were thermally stable up to 300 °C, and the cross-linked electrolyte membrane (CL-HBP-(PA)2) had suitable thermal stability as an electrolyte membrane for the high-temperature fuel cells under dry condition. Fuel cell measurement using a single membrane electrode assembly cell with the cross-linked membrane was performed. 相似文献
165.
Shuhei Furukawa Kenji Hirai Keiji Nakagawa Yohei Takashima Ryotaro Matsuda Takaaki Tsuruoka Mio Kondo Rie Haruki Daisuke Tanaka Hirotoshi Sakamoto Satoru Shimomura Osami Sakata Susumu Kitagawa 《Angewandte Chemie (International ed. in English)》2009,48(10):1697-1697
A porous copper coordination framework grew epitaxially as a single crystal on the surface of a single crystal of a porous zinc coordination framework, as described by S. Kitagawa and co‐workers in their Communication on page 1766 ff. The picture shows the structural relationship between the copper and zinc frameworks, which has been unveiled by synchrotron surface X‐ray diffraction measurements; in‐plane rotational epitaxial growth compensates for the different lattice constants of the two crystals.
166.
Synthetic study for two 2H‐chromenic acids, 8‐chlorocannabiorcichromenic acid and mycochromenic acid
Seiji Yamaguchi Masahiro Nedachi Mikiko Maekawa Yohei Murayama Masahiro Miyazawa Yoshiro Hirai 《Journal of heterocyclic chemistry》2006,43(1):29-41
Two 2H‐chromenes having a fully substituted benzene ring, 8‐chlorocannabiorcichromene ( 1 ) and mycochromenic acid ( 2 ), were synthesized by a condensation of salicylaldehydes with isopropylidenemalonate or the thermal cyclization of corresponding propargyl ethers. 相似文献
167.
Palladium and rhodium catalyzed the addition of H-phosphine oxides to isocyanides to selectively generate alpha-iminophosphine oxides and bisphosphinoylaminomethanes, respectively. 相似文献
168.
Yuji Hirai Hiroshi Yabu Yasutaka Matsuo Kuniharu Ijiro Masatsugu Shimomura 《Macromolecular Symposia》2010,295(1):77-80
Summary: Self-organized honeycomb-patterned polymer films were prepared by using condensed water droplet arrays as templates. Porous polymer masks for dry etching were easily prepared on Si substrates by peeling off the honeycomb-patterned films. After dry etching, hexagonally-arranged micro-pores were formed on the surface of Si substrates. 相似文献
169.
Three new amino acid derivatives (1-3) and three known ones (4-6) were isolated from the mushroom Pleurocybella porrigens. The structures of 1-6 were determined by the interpretation of spectroscopic data. Compounds 1, 3, 4, and 5 were toxic to mouse cerebrum glial cells. 相似文献
170.
Shiraishi Y Morishita M Teshima Y Hirai T 《The journal of physical chemistry. B》2006,110(13):6587-6594
Vanadium-containing mesoporous silica molecular sieve (V proportional HMS) with tetrahedrally coordinated V-oxide species (VVO4) has been prepared by a modified surfactant-templating method, consisting of an addition of surfactant to a mixture of water, alcohol, and Si and V precursors followed by calcination. The V proportional HMS demonstrates high photocatalytic activity even in the presence of water, while other V proportional HMS's prepared by conventional templating methods and V/HMS prepared by an impregnation method show almost no activity owing to hydrolysis of the VVO4 species. ESR and photoluminescence measurements reveal that the modified templating method creates VVO4 species confined within a silica layer, while other methods create VVO4 species exposed on silica surface. The former VVO4 species are highly stabilized by the confinement within the silica, thus suppressing the hydrolysis. Another notable property of the confined VVO4 species is the higher photocatalytic activity even without water, despite their confined structure. This is explained by higher electrophilicity and longer lifetime of the excited-state VVO4 species (VIVO4*) derived from their distorted structure. The obtained findings suggest potential use of the modified surfactant-templating method for synthesis of stable and recyclable V-containing mesoporous silica with high photocatalytic activity. 相似文献