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Takahashi, Shuichi; Maekawa, Yasunari; Hagiwara, Tokio*; Okonogi, Hiroyuki*
no journal, ,
Aliphatic vinyl monomers, like acrylatic acid derivatives or vinyl ketones, were grafted by 
-ray irradiation on a poly(ethylene-co-tetrafluoroethylene) (ETFE) film. Then, novel electrolyte membranes, which possess alkyl sulfonic acids on grafted chain, were synthesized by polymeric transformation of functional groups. The electrolyte membranes prepared by the above approach showed higher heat-stability in the wet condition compared to the electrolyte membranes with sulfonated styrene grafted membranes.
Yoshida, Masaru; Asano, Masaharu; Chen, J.; Maekawa, Yasunari; Sakamura, Takahiro*; Kubota, Hitoshi*
no journal, ,
no abstracts in English
Chen, J.; Asano, Masaharu; Yoshida, Masaru; Maekawa, Yasunari
no journal, ,
PEEK film was crosslinked by electron-beam irradiation in order to prepare polymer electrolyte membranes by one-step sulfonation without a membrane casting process. The crosslinked PEEK film can withstand in a sulfonating solution so that PEEK electrolyte membranes can be directly prepared by only a sulfonation step. It was found that a PEEK film can be effectively crosslinked under the doses of above 67 MGy, where the gel fraction reached up to 85 %. The crosslinked PEEK film was converted to a polymer electrolyte membrane by the sulfonation in a chlorosulfonic acid solution. The resultant membrane showed high proton conductivity comparable to Nafion; nevertheless, its water uptake was less than 100 %, which is moderate for the application in fuel cells. The heat-treatment was effective for further crosslinking of the membrane; as a result, the water uptake decreased to be about 50%.
Shimojo, Kojiro; Naganawa, Hirochika; Oshima, Tatsuya*; Goto, Masahiro*
no journal, ,
no abstracts in English
Chen, J.; Asano, Masaharu; Yoshida, Masaru; Maekawa, Yasunari
no journal, ,
In order to prepare a polymer electrolyte hybrid membrane with both high proton conductivity and high thermal stability, an aromatic vinyl monomer having a trimethoxysilyl group was first grafted into ETFE film by preirradiation. The styrylsilane-grafted film was then sulfonated, and finally hydrolyzed and condensed to introduce silane-crosslinking between the graft chains. Thus, a crosslinked proton-conducting polymer electrolyte hybrid membrane was obtained. The preparation conditions for grafting and sulfonation, and the properties of the resulting polymer electrolyte membrane, such as ion exchange capacity, proton conductivity, water uptake, and thermal stability, were investigated with respect to its application in fuel cells. It is concluded that the properties of the new p-styrylsilane-grafted polymer electrolyte hybrid membrane are comparable to Nafion, and are superior to a styrene-grafted membrane.
media for chemical investigation of DbKasamatsu, Yoshitaka; Toyoshima, Atsushi; Tome, Hayato; Tsukada, Kazuaki; Haba, Hiromitsu*; Nagame, Yuichiro
no journal, ,
Anion-exchange behavior of Nb, Ta and Pa in HF/HNO media was investigated in order to find suitable experimental conditions for the study of Db fluoride complex formation. Distribution ratios of the elements on strongly basic anion exchangers were measured in the wide range of the fluoride ion concentration. We discuss the formation of anionic fluoride complexes of the elements on the basis of the variations of the distribution ratios against [F
] and [NO]. Based on these results together with the results of the kinetic studies, we propose rapid online experimental conditions for the chromatographic study of Db.
Toyoshima, Atsushi; Kasamatsu, Yoshitaka; Kitatsuji, Yoshihiro; Tsukada, Kazuaki; Ishii, Yasuo; Tome, Hayato; Asai, Masato; Haba, Hiromitsu*; Akiyama, Kazuhiko*; Oe, Kazuhiro*; et al.
no journal, ,
no abstracts in English
Yokoyama, Atsushi; Oba, Hironori; Akagi, Hiroshi; Yokoyama, Keiichi; Saeki, Morihisa; Katsumata, Keiichi*
no journal, ,
no abstracts in English
Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Hirao, Norie*; Nath, K. G.*
no journal, ,
no abstracts in English
Imai, Yoshiyuki; Nakajima, Hayato; Kasahara, Seiji; Kubo, Shinji; Onuki, Kaoru
no journal, ,
Effect of sulfur dioxide partial pressure on the reaction of iodine, sulfur dioxide and water, which is a unit reaction of thermochemical hydrogen production IS process, was studied experimentally under iodine saturated condition. Quasi-equilibrium state was observed in the presence of sulfur dioxide gas of constant pressure. The composition of the poly-hydriodic acid solution was discussed assuming an ideal desulfurization using the reverse reaction of the Bunsen reaction. The value of HI/(HI+H
O) of the desulfurized solution was high in great sulfur dioxide pressure.
O
Yoshii, Kenji; Ikeda, Naoshi*; Mori, Shigeo*
no journal, ,
no abstracts in English
Shiwaku, Hideaki; Kobayashi, Toru; Numakura, Masahiko; Yaita, Tsuyoshi; Okamoto, Yoshihiro; Suzuki, Shinichi; Suda, Hiroki*; Fujii, Yuki*
no journal, ,
no abstracts in English
Honda, Mitsunori; Baba, Yuji; Hirao, Norie*; Deng, J.; Sekiguchi, Tetsuhiro
no journal, ,
no abstracts in English
Narita, Ayumi*; Honda, Mitsunori; Hirao, Norie*; Baba, Yuji; Yaita, Tsuyoshi
no journal, ,
no abstracts in English
Hirao, Norie*; Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Honda, Mitsunori; Deng, J.
no journal, ,
no abstracts in English
Numakura, Masahiko; Yaita, Tsuyoshi; Shiwaku, Hideaki; Kobayashi, Toru; Okamoto, Yoshihiro; Suzuki, Shinichi; Ikeda, Atsushi*
no journal, ,
Influences of thee different phenanthorolines (Phens) with which substituent differs, i.e., Phen, Methyl-Phen:MPhen, and Nitro-Phen:NPhen, on their structure and electronic structure formation were studied by EXAFS and XPS methods. The radial structural functions of EXAFS suggested that Lu ion forms 1:3, 1:2, and 1:1 complexes in metal to Phen ratios with Phen, MPhen, and NPhen, respectively. Moreover, the process of which Phen nitrogen with a small backscattering factor exchanges with chloride ion with a large one was clearly observed in the radial structural function of EXAFS. XPS spectra did not show any difference in both the valence level and inner-shell structures among the spectra for three Phens, while clear differences on the spectra of valence level between light lanthanide and heavy lanthanide complexes were observed.
/HF solutionIshii, Yasuo; Tome, Hayato; Toyoshima, Atsushi; Asai, Masato; Nishinaka, Ichiro; Tsukada, Kazuaki; Nagame, Yuichiro; Miyashita, Sunao*; Mori, Tomotaka*; Suganuma, Hideo*; et al.
no journal, ,
The cation-exchange behavior of rutherfordium(Rf) in HNO/HF solution has been studied based on an atom-at-a-time scale. In the symposium, we will discuss the fluoride complexation of rutherfordium in comparison with that of Zr, Hf and Th.
solutions; Model experiment for chemical study of element 105 (Db)Tome, Hayato; Kasamatsu, Yoshitaka; Toyoshima, Atsushi; Ishii, Yasuo; Tsukada, Kazuaki; Haba, Hiromitsu*; Shinohara, Nobuo; Nagame, Yuichiro
no journal, ,
Aiming at clarifying chemical properties of the transactinide element dubnium (Db), we plan to study the fluoride complexation of Db in mixed HF/HNO solutions by a cation exchange technique. In the present study, we report the cation exchange behavior of niobium (Nb) and tantalum (Ta) as a homologue of Db in mixed HF/HNO solutions by tracer experiments.
Miyamoto, Nobuyoshi; Koizumi, Satoshi; Hashimoto, Takeji
no journal, ,
no abstracts in English