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glass at high-PT condition by in-situ neutron diffractionHattori, Takanori; Sano, Asami; Inamura, Yasuhiro; Yagafarov, O.*; Katayama, Yoshinori*; Chiba, Ayano*; Otomo, Toshiya*; Funakoshi, Kenichi*; Abe, Jun*; Machida, Shinichi*; et al.
no journal, ,
SiO glass consists of SiO
tetrahedra which are mutually connected and forms the many-membered ring. Thus, the glass has large void in its structure, and therefore marked densification is expected under pressure. Actually, it is known that the density increases by 20% on compression to 8 GPa, accompanying the change in the intermediate range order. The density goes back to the original value by decompression, whereas the high-density state is retained at ambient condition once the structure is relaxed by being heated at high pressures. In this study, the mechanism of the densification at room-temperature and high-temperature has been investigated by in-situ high-pressure neutron diffraction at high-pressure neutron beamline PLANET in J-PARC. Then, we have constructed 3-dimensional atomic arrangements by Reverse Monte Carlo simulation, coupling with previously reported X-ray data. In this talk, the mechanism of densification at room-temperature and high-temperature and their differences will be discussed based on the obtained atomic arrangements.
Harada, Masahide; Uchida, Toshitsugu; Sekijima, Mitsuaki; Haga, Katsuhiro; Kogawa, Hiroyuki; Kinoshita, Hidetaka; Takada, Hiroshi
no journal, ,
no abstracts in English
Aso, Tomokazu; Teshigawara, Makoto; Hasegawa, Shoichi; Muto, Hideki; Aoyagi, Katsuhiro; Nomura, Kazutaka; Takada, Hiroshi
no journal, ,
no abstracts in English
Haga, Katsuhiro; Wakui, Takashi; Wakai, Eiichi; Kogawa, Hiroyuki; Naoe, Takashi; Takada, Hiroshi
no journal, ,
In 2015, we experienced failure in the water shroud of the mercury target vessel while they were in operation with the proton beam power of 500 kW, and since then investigations for the failure cause were carried out. As a result, it revealed that the target failures had been resulted from conditions which were difficult to examine by analytical approaches at the stage of target design, e.g., those relating to the bonding/welding processes. In order to prevent such troubles and to improve the reliability and soundness of the target vessel, we decided the design strategies to minimize welding part by using wire EDM and to increase radiographic and ultrasonic test during fabrication process. For the front part of the target vessel where the heat density by proton injection is high, the mercury vessel and the water shroud will be cut out from a block of stainless steel. The components of the rear part will also be decreased and total welding length will be reduced by 70 %.
Hiroi, Kosuke; Shinohara, Takenao; Hayashida, Hirotoshi*; Parker, J. D.*; Oikawa, Kenichi; Su, Y. H.; Kai, Tetsuya; Kiyanagi, Yoshiaki*
no journal, ,
Quantification of a magnetic field in an electric motor under driving state and comparing it with the designed value are important in developing high efficiency motors. However, measuring techniques of field distribution in the motor has not been established so far. Magnetic field imaging technique using polarized pulsed neutrons is thought to be a promising method to quantify field distribution in the rotating motor. In this study, we observed field distribution in a rotating model electric motor using polarized pulsed neutron imaging at BL22 RADEN in MLF. The model motor was driven by an AC current whose frequency was 21.5 Hz and temporal changes in polarization distribution of the rotating motor was measured by means of the AC field imaging technique. We successfully observed change in polarization distribution between driving and static state, which is caused by the energy loss of the motor driving.
Oi, Motoki; Teshigawara, Makoto; Harada, Masahide
no journal, ,
At the spallation neutron source of the Japan Proton Accelerator Complex (J-PARC), the design life of the moderator vessels is 30,000 MWh and we are preparing a moderator vessel for replacement. In the next moderator vessel, Au-In-Cd alloy is used as a decoupler material for short pulse and reducing the residual radio activities. The decoupler is formed by combining spherical surfaces having plural radius. For that reason, we adopted casting for making decouplers. In this study, we explain about fabrication of the Au-In-Cd alloy decoupler.
RhSiYamauchi, Hiroki; Shamoto, Shinichi; Kondo, Keietsu; Ishikado, Motoyuki*; Hagihara, Masato*; Chi, S.*; Fernandez-Baca, J. A.*
no journal, ,
no abstracts in English
Shimojo, Yutaka; Sakata, Mami; Hayashi, Kazuhiko; Kawana, Daichi*; Asami, Toshio*; Sugiura, Ryosuke*; Okawara, Manabu*
no journal, ,
no abstracts in English
Shamoto, Shinichi; Ito, Takashi; Mori, Michiyasu; Maekawa, Sadamichi; Kajimoto, Ryoichi; Inamura, Yasuhiro; Nakamura, Mitsutaka; Kawamura, Seiko; Shibata, Kaoru; Matsuura, Masato*; et al.
no journal, ,
no abstracts in English
La
O
studied by PDF analysis and MEMSaruwatari, Koji*; Nagasaki, Takanori*; Kodama, Katsuaki; Igawa, Naoki; Ishigaki, Toru*
no journal, ,
The average and local structures of CeLaO which is one of the excellent proton conductors were analyzed by using the Rietveld/ Maximum Entropy Method (MEM) and the Atomic Pair Distribution Function (PDF) analysis method with the neutron diffraction. The lattice parameter of hydrogen doped CeLaO is larger than those of undoped sample. This result is caused by the effect of hydrogen doping. The peaks of the PDF profiles were slightly wider than those of normal crystals. This phenomenon shows the local disorder exists in the samples. In this work, the relationship between the average and local structures of hydrogen doped and undoped CeLaO will be discussed.
CuMo
O
Yasui, Yukio*; Fujimura, Akio*; Omori, Kiyoshi*; Igawa, Naoki; Matsukawa, Takeshi*; Yoshida, Yukihiko*; Hoshikawa, Akinori*; Ishigaki, Toru*
no journal, ,
The magnetic structure of CsCuMoO with CuO ribbon chains have been studied by using the neutron powder diffraction. The magnetic reflections were observed below 
= 1.85 K and all of the magnetic reflections overlapped Bragg reflections. Considering that these are 16-Cu
ions in the unit cell, CsCuMoO has the collinear-antiferromagnetic structure.
Kikuchi, Tatsuya; Nakajima, Kenji; Kawakita, Yukinobu; Wakimoto, Shuichi; Ikeuchi, Kazuhiko*; Fujita, Masaki*; Kajimoto, Ryoichi; Inamura, Yasuhiro; Suzuya, Kentaro; Kawasaki, Takuro; et al.
no journal, ,
no abstracts in English
Kawasaki, Takuro; Harjo, S.; Nakamura, Tatsuya; Aizawa, Kazuya
no journal, ,
no abstracts in English
Watanabe, Masao; Nojiri, Hiroyuki*
no journal, ,
Recently, neutron scattering experiments have been rapidly progressed under high magnetic field. In the J-PARC, proto-type compact pulse magnet system with the power supply, the coil and the sample stick has been developed. Basic specifications of the power supply are as follows; maximum charged voltage with capacitor is 2 kV, maximum current is 8 kA, repetition rate is a pulse per several minutes and pulse duration is several msec. Maximum magnetic field in the coil is more than 30 Tesla. The sample stick is designed for Orange-Cryostat. In this presentation, We report the details of the pulsed magnet system and the performance of it on neutron scattering experiments at MLF beam line.
Inamura, Yasuhiro; Nakatani, Takeshi; Ito, Takayoshi*; Suzuki, Jiro*
no journal, ,
We report the current status of software development about "Utsusemi" and its applications for the effective utilization of event-recording data on the Materials and Life Science Experimental Facility (MLF), the Japan Proton Accelerator Research Complex (J-PARC). Utsusemi is the one of analysis software frameworks utilized for the data reduction and visualization in MLF, including treatment of event-recorded data. To solve many problems Utsusemi included, for example, difficulty to install Utsusemi into user own PC, we produced Utsusemi binary package to run on Windows and MacOS to provide users widely. In addition, we did the procedure in JAEA to make Utsusemi be open source for effective distributions for users on the internet.
Su, Y. H.; Oikawa, Kenichi; Shinohara, Takenao; Kai, Tetsuya; Hiroi, Kosuke; Hayashida, Hirotoshi*; Zhang, S.*; Parker, J. D.*; Matsumoto, Yoshihiro*; Sato, Hirotaka*; et al.
no journal, ,
Shibata, Kaoru
no journal, ,
A time-of-flight (TOF) type near-backscattering spectrometer (n-BSS), DNA was built and started operation in 2012 at the Materials and Life Science Experimental Facility (MLF) of the Japan Proton Accelerator Research Complex (J-PARC).
Ohara, Takashi; Kiyanagi, Ryoji; Nakao, Akiko*; Munakata, Koji*; Moyoshi, Taketo*; Moriyama, Kentaro*
no journal, ,
no abstracts in English
Seki, Yoshichika; Shinohara, Takenao; Ueno, Wakana; Seeghilaridjani, M.*; Kato, Hidemi*; Samoto, Tetsuo*; Yashiro, Wataru*; Momose, Atsushi*
no journal, ,
no abstracts in English
Ueno, Wakana; Shinohara, Takenao; Seki, Yoshichika; Kai, Tetsuya; Parker, J. D.*; Sadeghilaridjani, M.*; Kato, Hidemi*; Yashiro, Wataru*; Momose, Atsushi*
no journal, ,
no abstracts in English