Three-dimensional modeling for deformation and movement of siltfence in water; Coupled simulation of water flow and siltfence

Yamada, Susumu; Machida, Masahiko; Tanaka, Minori*; Seki, Katsumi*; Arikawa, Taro*

Nihon Oyo Suri Gakkai Rombunshi, 31(1), p.20 - 43, 2021/03

https://doi.org/10.11540/jsiamt.31.1_20

no abstracts in English

Study on the effect of preventing the spread of pollutants due to double installation of siltfence

Tanaka, Minori*; Watabane, Masashi*; Machida, Masahiko; Yamada, Susumu; Enomoto, Yota*; Gunji, Kota*; Arikawa, Taro*

Doboku Gakkai Rombunshu, B2 (Kaigan Kogaku) (Internet), 76(2), p.I_103 - I_108, 2020/11

https://doi.org/10.2208/kaigan.76.2_I_103

no abstracts in English

Study of catalytic reaction at electrode-electrolyte interfaces by a CV-XAFS method

Kusano, Shogo*; Matsumura, Daiju; Asazawa, Koichiro*; Kishi, Hirofumi*; Sakamoto, Tomokazu*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Mizuki, Junichiro*

Journal of Electronic Materials, 46(6), p.3634 - 3638, 2017/06

https://doi.org/10.1007/s11664-016-5259-x

Beam commissioning of the linac for iBNCT

Naito, Fujio*; Anami, Shozo*; Ikegami, Kiyoshi*; Uota, Masahiko*; Ouchi, Toshikatsu*; Onishi, Takahiro*; Oba, Toshiyuki*; Obina, Takashi*; Kawamura, Masato*; Kumada, Hiroaki*; et al.

Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1244 - 1246, 2016/11

http://www.pasj.jp/web_publish/pasj2016/proceedings/PDF/TUP1/TUP118.pdf

The proton linac installed in the Ibaraki Neutron Medical Research Center is used for production of the intense neutron flux for the Boron Neutron Capture Therapy (BNCT). The linac consists of the 3-MeV RFQ and the 8-MeV DTL. Design average beam current is 10mA. Target is made of Beryllium. First neutron production from the Beryllium target was observed at the end of 2015 with the low intensity beam as a demonstration. After the observation of neutron production, a lot of improvement s was carried out in order to increase the proton beam intensity for the real beam commissioning. The beam commissioning has been started on May 2016. The status of the commissioning is summarized in this report.

Development of non-PGM catalysts for anion exchange membrane fuel cells

Sakamoto, Tomokazu*; Kishi, Hirofumi*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Matsumura, Daiju; Tamura, Kazuhisa; Nishihata, Yasuo

Hyomen Kagaku, 37(2), p.78 - 83, 2016/02

https://doi.org/10.1380/jsssj.37.78

We have developed direct liquid fuel anion exchange membrane fuel cell vehicles to deal with the global warming. Non-platinum group metals (PGM) catalyst has been researched to apply for both anode and cathode electrodes. A test driving was carried out for the fuel cell vehicle equipped with no precious metals as catalysts at SPring-8 in 2013. Here we introduce our results of advanced analysis for reaction mechanism and active site of non-PGM catalyst using synchrotron radiation X-rays at SPring-8.

Imidazolium cation based anion-conducting electrolyte membranes prepared by radiation induced grafting for direct hydrazine hydrate fuel cells

Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Shishitani, Hideyuki*; Yamamoto, Kazuya*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Maekawa, Yasunari

Journal of the Electrochemical Society, 161(9), p.F889 - F893, 2014/06

https://doi.org/10.1149/2.0511409jes

Graft-type anion-conducting electrolyte membranes (AEMs) with imidazolium cations on graft polymers were synthesized through radiation-induced graft polymerization of -vinylimidazole (NVIm) on poly(ethylene-co-tetrafluoroethylene) (ETFE) films, followed by -propylation and ion-exchange reactions. The -propylation proceeded quantitatively, whereas the ion-exchange reactions in 1 M KOH at 60C were accompanied by partial -elimination of the imidazolium cations(AEM2), which exhibited an ion-exchange capacity (IEC) of 0.85 mmol g and ionic conductivity of 10 mS cm. AEM2 showed alkaline stability at 60C but it gradually degraded at 80C for ca. 150 h. The copolymer-type AEM (AEM3) with an IEC of 1.20 mmol g was prepared through the copolymerization of NVIm with styrene on ETFE films, followed by the same -propylation and ion-exchange reactions. AEM3 was shown higher alkaline durability in 1 M KOH at 80C. As a result, it exhibited higher conductivity (10 mS cm) for 250 h. Therefore, alkylimidazolium cations in copolymer grafts are a promising anion conducting group for alkaline-durable AEMs. A maximum power density of 75 mW cm is obtained for AEM3 in a direct hydrazine hydrate fuel cell.

Oxygen hole state in A-site ordered perovskite ACuRuO (A = Na, Ca, and La) probed by resonant X-ray emission spectroscopy

Mizumaki, Masaichiro*; Mizokawa, Takashi*; Agui, Akane; Tanaka, Sotaro*; Takatsu, Hiroshi*; Yonezawa, Shingo*; Maeno, Yoshiteru*

Journal of the Physical Society of Japan, 82(2), p.024709_1 - 024709_6, 2013/02

https://doi.org/10.7566/JPSJ.82.024709

In this study, we report the O 1 and Cu 2 X-ray absorption spectroscopy (XAS) and resonant X-ray emission spectroscopy (RXES) study on the A-site ordered perovskite ACuRuO (A = Na, Ca, and La). Hartree-Fock calculation and cluster model calculation were carried out to analyze O 1 and Cu 2 XAS spectra. The O 1 RXES spectra indicate that the number of O 2 holes increases in going from La to Ca to Na. In addition, the Cu 2 RXES spectra reveal that the charge-transfer energy decreases in going from La to Ca to Na.

Preparation of anion-exchange membranes for fuel cell applications by -ray pre-irradiation grafting

Koshikawa, Hiroshi; Yamaki, Tetsuya; Asano, Masaharu; Maekawa, Yasunari; Yamaguchi, Susumu*; Yamamoto, Kazuya*; Asazawa, Koichiro*; Yamada, Koji*; Tanaka, Hirohisa*

Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.240 - 241, 2011/06

The anion-exchange membranes (AEM) for fuel cells were prepared by the radiation-induced graft polymerization of chloromethylstyrene into poly(ethylene-co-tetrafluoroethylene) (ETFE) films and subsequent quaternization of the grafts with trimethylamine. When the AEM were treated in 1M-KOH and washed with N-saturated water, the membranes with chloride form can be converted quantitatively to hydroxide form. However, the hydroxide form was easily converted to the bicarbonate form by the treatment in non-bubbled (CO dissolved) water. When we introduced the crosslinkers in polymer grafts, which is proved to be very effective in the proton conducting PEM having a poly(styrenesulfonic acid) grafts, the grafted AEM with both chloride and hydroxide forms showed only slight decrease of water uptake. It should be noted that AEM with hydroxide form showed very high tendency to absorb water.

KEKCB electron cyclotron resonance charge breeder at TRIAC

Imai, Nobuaki*; Jeong, S.-C.*; Oyaizu, Mitsuhiro*; Arai, Shigeaki*; Fuchi, Yoshihide*; Hirayama, Yoshikazu*; Ishiyama, Hironobu*; Miyatake, Hiroari; Tanaka, Masahiko*; Okada, Masashi*; et al.

Review of Scientific Instruments, 79(2), p.02A906_1 - 02A906_3, 2008/02

https://doi.org/10.1063/1.2828070

KEKCB is an 18 GHz Electron Cyclotron Resonance (ECR) ion source and is a charge breeder device for converting mass-separated 1 radioactive ions to multi-ionized ones by utilizing an axial injection technique to the ECR plasma. It is a part of the Tokai Radioactive Ion Accelerator Complex (TRIAC) facility. Based on the developments so far, converting efficiencies for metal elements, such as barium and indium, and for gaseous elements, such as krypton and xenon, are improved to be 7 and 2 , respectively. And it is confirmed that the efficiency is nearly the constant for short-lived (t 1 sec) isotopes. Background ions mixed in the output beams are supressed to be 600 pps from 10 pps by applying all aluminum electrodes and high pressure pure-water cleanings.

Ratio of aerosol and gases of radioactive chlorine and particle size distribution of aerosol formed by high-energy proton irradiation

Yokoyama, Sumi; Sato, Kaoru; Manabe, Kentaro; Noguchi, Hiroshi; Kaneko, Hirohisa; Oki, Yuichi*; Iida, Takao*; Tanaka, Susumu*

Radiation Protection Dosimetry, 127(1-4), p.392 - 397, 2007/11

https://doi.org/10.1093/rpd/ncm475

To estimate internal doses due to the inhalation of radionuclides produced by the nuclear spallation of the air nuclei in high-energy proton accelerator facilities, the physicochemical properties of radionuclides are very important. However, there is not enough information of the properties for airborne radioactive chlorine formed from argon gas in the air of a high-energy proton irradiation field. Thus we have measured the ratio of aerosol and gases of radioactive chlorine which are formed by irradiating argon gas-added air with a 48 MeV proton beam. In addition, the particle size distribution and chemical form of non-radioactive aerosol were examined. It was found that Cl-38 and Cl-39 exist as aerosol, acidic and non-acidic gases. The percentages of Cl-38 and Cl-39 aerosols are more than 70%. In total radioactive chlorine gas, about 30% and 70% are acidic and non-acidic gases, respectively. The concentration of non-radioactive aerosol had a peak at an aerodynamic diameter of 20-30 nm in the early irradiation period. The particle size of non-radioactive aerosol shifted to larger with time. After 10 min, the aerosols grew very slowly and many of the non-radioactive aerosols were distributed widely under 200 nm. This suggests that the diameter of the radioactive chlorine aerosol formed by the attachment of the radioactive chlorine to the non-radioactive aerosol around a beam line of the accelerator is much smaller than the default value adopted in ICRP Publication 66.