Differential pressure rise event for filters of HTTR primary helium gas circulators, 1; Investigation of differential pressure rise event

Nemoto, Takahiro; Arakawa, Ryoki; Kawakami, Satoru; Nagasumi, Satoru; Yokoyama, Keisuke; Watanabe, Masashi; Onishi, Takashi; Kawamoto, Taiki; Furusawa, Takayuki; Inoi, Hiroyuki; et al.

JAEA-Technology 2023-005, 33 Pages, 2023/05

JAEA-Technology-2023-005.pdf:5.25MB

During shut down of the HTTR (High Temperature engineering Test Reactor) RS-14 cycle, an increasing trend of filter differential pressure for the helium gas circulator was observed. In order to investigate this phenomenon, the blower of the primary helium purification system was disassembled and inspected. As a result, it is clear that the silicon oil mist entered into the primary coolant due to the deterioration of the charcoal filter performance. The replacement and further investigation of the filter are planning to prevent the reoccurrence of the same phenomenon in the future.

Measurement of femtosecond laser ablation by soft X-ray laser interferometory and reflective imaging

Nishikino, Masaharu; Hasegawa, Noboru; Ishino, Masahiko; Yamagiwa, Mitsuru; Kawachi, Tetsuya; Minami, Yasuo*; Terakawa, Kota*; Takei, Ryota*; Baba, Motoyoshi*; Suemoto, Toru; et al.

JAEA-Conf 2013-001, p.16 - 19, 2013/09

https://doi.org/10.11484/jaea-conf-2013-001

The dynamics of the femtosecond laser ablation is still not clear at the early stage. Several studies on the time-resolved imaging of femtosecond laser ablation process have been performed on various materials. In this study, we have demonstrated a pump and probe imaging of the metal surface morphology during the femtosecond laser ablation by using the laser-driven plasma induced soft X-ray laser (SXRL) as a probe beam. The pumping laser used for ablation was a Ti:Sapphire laser system based on chirped pulse amplification. The pump beam had a Gaussian profile and the focal spot size on the metal surface was about 70 micron at FWHM. The dependence for the pump laser fluence of the ablation surface expansion and the surface condition (roughness and density gradient) were observed from the soft X-ray interferogram and reflective image, respectively.

Neutron and X-ray crystallographic analysis of the human -thrombin-bivalirubin complex at pD 5.0; Protonation states and hydration structure of the enzyme-product complex

Yamada, Taro*; Kurihara, Kazuo; Onishi, Yuki*; Tamada, Taro; Tomoyori, Katsuaki; Masumi, Kenji*; Tanaka, Ichiro*; Kuroki, Ryota; Niimura, Nobuo*

Biochimica et Biophysica Acta; Proteins and Proteomics, 1834(8), p.1532 - 1538, 2013/08

https://doi.org/10.1016/j.bbapap.2013.05.014

The protonation states and hydration structures of the -thrombin-bivalirubin complex were studied by joint XN refinement of the single crystal X-ray and neutron diffraction data at resolutions of 1.6 and 2.8 , respectively. The atomic distances were estimated by carrying out X-ray crystallographic analysis at 1.25 resolution. The complex represents a model of the enzyme-product (EP) complex of -thrombin. The neutron scattering length maps around the active site suggest that the side chain of H57/H was deuterated. The joint XN refinement showed that occupancies for D1 and D2 of H57/H were 1.0 and 0.7, respectively. However, no significant neutron scattering length density was observed around the hydroxyl oxygen O of S195/H, which was close to the carboxylic carbon atom of dFPR-COOH. These observations suggest that the O atom of S195/H is deprotonated and maintains its nucleophilicity in the EP complex. In addition to the active site, the hydration structures of the S1 subsite and the Exosite I, which are involved in the recognition of bivalirudin, are presented.

Safety strategy of JSFR eliminating severe recriticality events and establishing in-vessel retention in the core disruptive accident

Sato, Ikken; Tobita, Yoshiharu; Konishi, Kensuke; Kamiyama, Kenji; Toyooka, Junichi; Nakai, Ryodai; Kubo, Shigenobu*; Kotake, Shoji*; Koyama, Kazuya*; Vassiliev, Y. S.*; et al.

Journal of Nuclear Science and Technology, 48(4), p.556 - 566, 2011/03

https://doi.org/10.3327/jnst.48.556

In the JSFR design, elimination of severe recriticality events in the Core Disruptive Accident (CDA) is intended as an effective measure to assure retention of the core materials within the reactor vessel. The design strategy is to control the potential of excessive void reactivity insertion in the Initiating Phase selecting appropriate design parameters such as maximum void reactivity on one hand, and to exclude core-wide molten-fuel-pool formation, which has been the main issue of CDA, with introduction of Inner Duct on the other hand. The effectiveness of these measures are reviewed based on existing experimental data and evaluations performed with validated analysis tools. It is judged that the present JSFR design can exlude severe power burst events.

A Neutron crystallographic analysis of phosphate-free ribonuclease A at 1.7 resolution

Yagi, Daichi*; Yamada, Taro*; Kurihara, Kazuo; Onishi, Yuki*; Yamashita, Masahiro*; Tamada, Taro; Tanaka, Ichiro*; Kuroki, Ryota; Niimura, Nobuo*

Acta Crystallographica Section D, 65(9), p.892 - 899, 2009/09

https://doi.org/10.1107/S0907444909018885

A neutron crystallographic analysis of phosphate-free bovine pancreatic RNase A has been carried out at 1.7 resolution using the BIX-4 single-crystal diffractometer at the JRR-3 reactor of the Japan Atomic Energy Agency. The high resolution structural model allowed us to determine that His12 acts mainly as a general base in the catalytic process of RNase A. Numerous other distinctive structural features such as the hydrogen positions of methyl groups, hydroxyl groups, prolines, asparagines and glutamines were also determined at 1.7 resolution. The protonation and deprotonation states of all of the charged amino-acid residues allowed us to provide a definitive description of the hydrogen-bonding network around the active site and the H atoms of the key His48 residue. Differences in hydrogen-bond strengths for the -helices and -sheets were inferred from determination of the hydrogen-bond lengths and the H/D-exchange ratios of the backbone amide H atoms. The correlation between the B factors and hydrogen-bond lengths of the hydration water molecules was also determined.

Reliability evaluation of SPEEDI's prediction by comparison with calculated results based on meteorological observation data

Rintsu, Yuko*; Serizawa, Shigeru*; Yamazaki, Tetsuo*; Umeyama, Nobuaki*; Moriuchi, Shigeru*; Handa, Hiroyuki*; Onishi, Ryoichi*; Takemura, Morio*; Chino, Masamichi; Nagai, Haruyasu; et al.

Proceedings of 16th Pacific Basin Nuclear Conference (PBNC-16) (CD-ROM), 6 Pages, 2008/10

no abstracts in English

Mechanistic study on lithium intercalation using a restricted reaction field in LiNiMnO

Sakamoto, Kazuyuki*; Konishi, Hiroaki*; Sonoyama, Noriyuki*; Yamada, Atsuo*; Tamura, Kazuhisa; Mizuki, Junichiro; Kanno, Ryoji*

Journal of Power Sources, 174(2), p.678 - 682, 2007/12

https://doi.org/10.1016/j.jpowsour.2007.06.240

Structure changes of LiNiMnO were detected at the electrode/electrolyte interface of lithium cell using synchrotron X-ray scattering and two-dimensional model electrodes. The electrodes were constructed by an epitaxial film of LiNiMnO synthesized by pulsed laser deposition (PLD) method. The orientation of the film depends on the substrate plane; the 2D layer of LiNiMnO is parallel to the SrTiO(1 1 0) substrate ((1 1 0) LiNiMnO//(1 1 0) SrTiO), while the 2D layer is perpendicular to the SrTiO(1 1 1) substrate ((0 0 3) LiNiMnO//(1 1 1) SrTiO). The X-ray diffraction of LiNiMnO(0 0 3) confirmed three-dimensional lithium diffusion through the two-dimensional transition meal layers. The intercalation reaction of LiNiMnO will be discussed.

Challenge to innovative technologies and the expected market appeal

Tobita, Kenji; Konishi, Satoshi*; Tokimatsu, Koji*; Nishio, Satoshi; Hiwatari, Ryoji*

Purazuma, Kaku Yugo Gakkai-Shi, 81(11), p.875 - 891, 2005/11

https://doi.org/10.1585/jspf.81.875

no abstracts in English

Tritium issues toward fusion plants

Konishi, Satoshi; Tobita, Kenji; Nishio, Satoshi; Okada, Hidetoshi*; Kurihara, Ryoichi

Fusion Science and Technology, 41(3), p.817 - 820, 2002/05

no abstracts in English

Construction of integration system with MpCCI for heterogeneous computational methods

Guo, Z.; Onishi, Ryoichi*; Kimura, Toshiya*; Hirayama, Toshio

Proceedings of International Conference on Computational Engineering & Science (ICES 2001) (CD-ROM), 6 Pages, 2001/00

no abstracts in English