Hydration states of europium(III) adsorbed on silicas with nano-sized pores

Murota, Kento*; Aoyagi, Noboru; Mei, H.; Saito, Takumi*

Applied Geochemistry, 152, p.105620_1 - 105620_11, 2023/05

https://doi.org/10.1016/j.apgeochem.2023.105620

Operation status of J-PARC timing system and future plan

Kamikubota, Norihiko*; Kikuzawa, Nobuhiro; Tamura, Fumihiko; Yamamoto, Noboru*

Proceedings of 15th International Conference on Accelerator and Large Experimental Physics Control Systems (ICALEPCS 2015) (Internet), p.988 - 991, 2016/01

https://doi.org/10.18429/JACoW-ICALEPCS2015-WEPGF121

The beam commissioning of J-PARC started in November, 2006. Since then, the timing system of J-PARC accelerator complex has contributed stable beam operations of three accelerators: a 400-MeV linac (LI), a 3-GeV rapid cycling synchrotron (RCS), and a 50-GeV synchrotron (MR). The timing system handles two different repetition cycles: 25 Hz for LI and RCS, and 2.48-6.00 sec. for MR (MR cycle). In addition, the timing system is capable to provide beams to two different experimental facilities in single MR cycle: Material and Life Science Experimental Facility (MLF) and Neutrino Experimental Facility (NU), or, MLF and Hadron Experimental Facility (HD). Recently, a plan to introduce a new facility, Accelerator-Driven Transmutation Experimental Facility (ADS), around 2018, has been discussed. This paper reviews the 8-year operation experience of the J-PARC timing system, followed by a present perspective of upgrade studies.

An X-ray diffraction study on a single rod outer segment from frog retina

Yagi, Naoto*; Matsuo, Tatsuhito; Ota, Noboru*

Journal of Synchrotron Radiation, 19(4), p.574 - 578, 2012/07

https://doi.org/10.1107/S0909049512018535

X-ray diffraction patterns were recorded from isolated single rod outer segments of frog. The outer segments in Ringer's solution were exposed to a 6 m microbeam (15 keV) at the BL40XU beamline, SPring-8. The diffraction pattern demonstrated a remarkable regularity in the stacking and flatness of the disk membranes. The electron density profile calculated from the intensity of up to tenth-order reflections showed a pair of bilayers that comprise a disk membrane. The structure of the disk membrane and the changes in the profile on swelling generally agreed with previous reports. Radiation damage was significant with an irradiation of 5 10 Gy which is much lower than the known damaging dose on proteins at the liquid-nitrogen temperature.

Aspect-ratio-dependent phase transitions and concentration fluctuations in aqueous colloidal dispersions of charged platelike particles

Yamaguchi, Daisuke; Miyamoto, Nobuyoshi*; Fujita, Takako*; Nakato, Teruyuki*; Koizumi, Satoshi; Ota, Noboru*; Yagi, Naoto*; Hashimoto, Takeji

Physical Review E, 85(1), p.011403_1 - 011403_15, 2012/01

https://doi.org/10.1103/PhysRevE.85.011403

Phase transition of aqueous colloidal dispersions of charged plate-like particles of niobate nanosheets were investigated as a function of the aspect ratio () and particle volume concentration () by small-angle neutron scattering and small-angle X-ray scattering. The results elucidated the following three pieces of evidence: (1) the macroscopic phase separation of the dispersions into an isotropic phase and a liquid crystalline phase (LC) under the condition of (a) varying at a constant = 0.01, and of (b) varying (0.01 0.025) at a constant = 2.510. (2) the -induced phase transition of the LC phase from a nematic phase to a highly periodic layered phase upon increasing r under the condition (a). (3) the LC phase having remarkable concentration fluctuations of the particles which are totally unexpected for the conventional lyotropic molecular LC but which are anticipated to be general for the plate-like colloidal particles.

Current status of the control system for J-PARC accelerator complex

Yoshikawa, Hiroshi; Sakaki, Hironao; Sako, Hiroyuki; Takahashi, Hiroki; Shen, G.; Kato, Yuko; Ito, Yuichi; Ikeda, Hiroshi*; Ishiyama, Tatsuya*; Tsuchiya, Hitoshi*; et al.

Proceedings of International Conference on Accelerator and Large Experimental Physics Control Systems (ICALEPCS '07) (CD-ROM), p.62 - 64, 2007/10

J-PARC is a large scale facility of the proton accelerators for the multi-purpose of scientific researches in Japan. This facility consists of three accelerators and three experimental stations. Now, J-PARC is under construction, and LINAC is operated for one year, 3GeV synchrotron has just started the commissioning in this October the 1st. The completion of this facility will be next summer. The control system of accelerators established fundamental performance for the initial commissioning. The most important requirement to the control system of this facility is to minimize the activation of accelerator devices. In this paper, we show that the performances of each layer of this control system have been achieved in the initial stage.

Results of safety research on radioactive waste disposal (H13-17)

Miyahara, Kaname; Nakatsuka, Noboru; Uchida, Masahiro; Shigeta, Naotaka; Ota, Kunio; Nohara, Tsuyoshi; Semba, Takeshi

no journal, , 

The results of five issues for safety research on radioactive waste from 2001 to 2005 introduced in the sectional committee of the safety research on radioactive waste. The five issues are as follows, (1) Study on a basic strategy for post-generic safety assessment, (2) Study on long-term stability for geological environment, (3) Methodology development for the characterization of crystalline rock, (4) Establishment of techniques for characterization of sedimentary formations, (5) Natural analogue study on geological environment.

Liquid crystalline phases in colloidal suspensions of KNbO nanosheets

Yamaguchi, Daisuke; Miyamoto, Nobuyoshi*; Fujita, Takako*; Nakato, Teruyuki*; Koizumi, Satoshi; Yagi, Naoto*; Ota, Noboru*; Hashimoto, Takeji

no journal, , 

Formation of lyotropic liquid crystalline (LC) phase was observed on a charged colloidal platelike particle system yielded from layered niobate crystal of KNbO. Firstly, the effect of mean lateral size (D) of the particle was examined at a constant volume fraction of the particle (.fai.) where a LC phase coexisted with an isotropic (I) phase. The coexisting LC phase was distinctly transformed from nematic to lamellar (L) as D was diminished. Secondly, the .fai. dependence of the interparticle distance (d) was examined along the I-L transition. In the coexistence region, d varied with .fai. and held nearly the same value between I and L phases, apparently deviating from gas-liquid condensation-type phase separation.

A New polarized neutron reflectometer installed at the intense pulsed neutron source of Materials and Life Science Experimental Facility (MLF) of J-PARC opening to International users

Takeda, Masayasu; Yamazaki, Dai; Soyama, Kazuhiko; Maruyama, Ryuji; Hayashida, Hirotoshi; Asaoka, Hidehito; Yamazaki, Tatsuya; Kubota, Masato; Aizawa, Kazuya; Inamura, Yasuhiro; et al.

no journal, , 

Current status of the new polarized neutron reflectometer (SHARAKU) at J-PARC, and prospects for study on multilayers

Kubota, Masato; Takeda, Masayasu; Yamazaki, Dai; Hayashida, Hirotoshi; Maruyama, Ryuji; Soyama, Kazuhiko; Asaoka, Hidehito; Yamazaki, Tatsuya; Sakasai, Kaoru; To, Kentaro; et al.

no journal, , 

no abstracts in English

A New polarized neutron reflectometer (SHARAKU) at the intense pulsed neutron source of the Materials and Life Science Experimental Facility of J-PARC

Takeda, Masayasu; Yamazaki, Dai; Soyama, Kazuhiko; Maruyama, Ryuji; Hayashida, Hirotoshi; Asaoka, Hidehito; Yamazaki, Tatsuya; Kubota, Masato; Aizawa, Kazuya; Arai, Masatoshi; et al.

no journal, ,