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Kunieda, Satoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Minato, Futoshi; Okamoto, Tsutomu; Sato, Tatsuhiko; Nakashima, Hiroshi; Iwamoto, Yosuke; Iwamoto, Hiroki; Kitatani, Fumito; et al.
JAEA-Conf 2016-004, p.41 - 46, 2016/09
Neutron- and proton-induced cross-section data are required in a wide energy range beyond 20 MeV, for the design of accelerator applications. New evaluations are performed with recent knowledge in the optical and pre-equilibrium model calculations. We also evaluated cross-sections for p+Li and p+Be which have been highly requested from a medical field. The present high-energy nuclear data library, JENDL-4.0/HE, includes evaluated cross-sections for incident neutrons and protons up to 200 MeV (for about 130 nuclei). We overview substantial features of the library, i.e., (1) systematic evaluation with CCONE code, (2) challenges for evaluations of light nuclei and (3) inheritance of JENDL-4.0 and JENDL/HE-2007. In this talk, we also focus on the results of benchmark calculation for neutronics to show performance of the present library.
Takahashi, Shuichi*; Okonogi, Hiroyuki*; Hagiwara, Tokio*; Maekawa, Yasunari
Journal of Membrane Science, 324(1-2), p.173 - 180, 2008/10
Times Cited Count:37 Percentile:72.79(Engineering, Chemical)Polymer electrolyte membranes (PEM) consisting of alkylsulfonic acid were successfully synthesized by radiation-induced graft polymerization of methyl acrylate (MA) into a poly(ethylene-co-tetrafluoroethylene) (ETFE) film, followed by sulfonation at an -carbonyl carbon of the MA units in the grafting chain using an equimolar complex of chlorosulfonic acid and dioxane (ClSOH-Complex). The ion exchange capacity and ion conductivity of the MA-grafted PEM were controlled in the respective ranges of 0.54-1.47 mmol/g and 0.014-0.14 S/cm by changing the grafting degree. It has been confirmed by titrimetric and gravimetric analyses of sulfonic and carboxylic acids in the film that the sulfonation reaction is accompanied with decarboxylation of the MA units equimolar to the substituted sulfonic acids (substitution of carboxylic acid with sulfonic acid), that the sulfonation degree was about 30%.
Maekawa, Yasunari; Kato, Jun*; Katakai, Masashi*; Ishihara, Masaaki*; Enomoto, Kazuyuki; Hagiwara, Tokio*; Ishii, Tatsuhito*; Ito, Kazuo*; Koshikawa, Hiroshi; Yoshida, Masaru
Macromolecular Chemistry and Physics, 209(6), p.625 - 633, 2008/03
Times Cited Count:2 Percentile:7.34(Polymer Science)A polysulfonamide and copolymers consisting of sulfonamides and amides underwent Fries rearrangement and scission, forming amino groups upon EB irradiation. The EB irradiation of these films with a dose of 500 C/cm followed by the color forming reaction provided the color imaging of line/space patterns with resolution of 300 nm.
Hirota, Koichi; Kumagai, Akira; Kojima, Takuji; Hagiwara, Tokio*
no journal, ,
no abstracts in English
Fujisawa, Kenichi; Hakoda, Teruyuki; Shimada, Akihiko; Kojima, Takuji; Hagiwara, Tokio*
no journal, ,
no abstracts in English
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.
Takahashi, Shuichi; Maekawa, Yasunari; Hagiwara, Tokio*; Okonogi, Hiroyuki*
no journal, ,
Methyl acrylate monomer was grafted by -ray irradiation on a poly(ethylene-co-tetrafluoroethylene)(ETFE) film. Then, the novel polymer electrolyte membranes (PEM), which possess alkyl sulfonic acids on grafted chain, were synthesized by polymeric transformation of functional groups. The PEM prepared by the above approach were analyzed structurally and characterized well.
Maekawa, Yasunari; Takahashi, Shuichi; Hanh, T. T.*; Okonogi, Hiroyuki*; Hagiwara, Tokio*
no journal, ,
Polymer electrolyte membranes (PEMs) consisting of alkylsulfonic acid in grafting chains can be prepared by radiation-induced graft polymerization of methyl acrylate (MA) onto a poly(ethylene-co-tetrafluoroethylene) (ETFE) film, followed by the sulfonation of MA units in the grafting chains using an equimolar complex of chlorosulfonic acid and dioxane. The sulfonation reaction accompanied equimolar decarboxylation of the MA unit (substitution of carboxylic acid with sulfonic acid) to give the PEMs with conductivity of 0.01-0.11 S/cm. Furthermore, the replacement of the MA unit with methyl metacrylate (MMA) as a comonomer in grafting chains enhances the stability of the PEM at higher temperatures.
Tamura, Yoshitaka; Hasegawa, Shin; Maekawa, Yasunari; Hagiwara, Tokio*
no journal, ,
Nafion complexes with conjugated diaza compounds were prepared to evaluate the conductivity of water free polymer electrolyte membrane for fuel cells above 100C. These nonvolatile proton conductors in the complexes provide the possibility of proton transfer formed by conjugated hydrogen bond network similar to that formed in water. The conjugated diaza compounds such as 1,5-Diazabicyclo[4,3,0]-non-5-ene(DBN), were introduced into Nafion with 20 - 95mol% on the basis of sulfonic acid. The ion conductivity of the complex films with 92mol% of DBN showed 1.5 and 1.4 times higher than those of DBU and DMAP complex films at 120C under dry condition, respectively. The ion conductivity of the DBN complex drastically increased over DBN contents above 40mol% and reached to 10 S/cm.
Kunieda, Satoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Minato, Futoshi; Okamoto, Tsutomu; Sato, Tatsuhiko; Nakashima, Hiroshi; Iwamoto, Yosuke; Iwamoto, Hiroki; Kitatani, Fumito; et al.
no journal, ,
Neutron- and proton-induced evaluated nuclear data are required in a wide energy range for the design of accelerator applications. New evaluations are performed with recent progresses in the optical and pre-equilibrium model calculations. We also evaluated cross-sections for p + Li and p + Be which are highly requested from medical field. Our present high-energy nuclear data library, JENDL-4.0/HE, includes cross-sections for 132 nuclei up to 200 MeV. In this talk, we present the evaluation methods, evaluated double-differential cross-sections and results of benchmark calculations.
Ota, Tomonori*; Hagiwara, Tokio*; Sugimoto, Masaki; Yamamoto, Shunya; Koshikawa, Hiroshi; Yamaki, Tetsuya
no journal, ,
Nitrogen (N)-doped carbon-based electrocatalysts are expected as a platinum alternative material for cost reduction of polymer electrolyte membrane fuel cells. However, nobody has not yet established the method of introducing N atoms in a graphene structure at high concentrations. Therefore, our purpose is to propose a new method of N doping using electron beam irradiation at high temperatures in an ammonia atmosphere. We developed here a sample chamber with a heating device, gas inlet and outlet, which made it possible to perform the irradiation without any temperature change. As a result, the phenolic resin, that is, a source of carbon-based electrocatalysts was irradiated with 2 MeV electrons at a dose rate of 2 kGy/s while being maintained at 300 C with a high precision as 2 C.
Ota, Tomonori*; Yamaki, Tetsuya; Sugimoto, Masaki; Yamamoto, Shunya; Koshikawa, Hiroshi; Hagiwara, Tokio*
no journal, ,
Nitrogen-doped carbon-based catalysts are expected as Pt alternatives, and however there have been so far no established methods to introduce N atoms into graphene structures. Thus, we report N doping in carbon-based catalysts by electron beam (EB) irradiation in ammonia (NH). A precursor was phenolic resin or its mixture with 5 or 10 wt% cobalt(II) chloride (CoCl); it was then irradiated with 2 MeV electron beam up to a dose of 6 MGy in 1 vol% NH at 400C. This irradiated powder was carbonized in an Ar atmosphere at 800C for 1 h. An N-doping level reached an atomic concentration of ca. 0.5% when 5 wt% CoCl was mixed in the precursor.
Sugimoto, Masaki; Ota, Tomonori*; Yamamoto, Shunya; Koshikawa, Hiroshi; Yamaki, Tetsuya; Hagiwara, Tokio*
no journal, ,
no abstracts in English