Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Takeuchi, Yusuke*; Tojo, Junji*; Nakazawa, Yuga*; Kondo, Yasuhiro; Kitamura, Ryo; Morishita, Takatoshi; Cicek, E.*; Ego, Hiroyasu*; Futatsukawa, Kenta*; Kawamura, Naritoshi*; et al.
Proceedings of 13th International Particle Accelerator Conference (IPAC 22) (Internet), p.1534 - 1537, 2022/06
The muon g-2/EDM experiment is under preparation at Japan Proton Accelerator Research Complex (J-PARC), and the muon linear accelerator for the experiment is being developed. A Disk-and-Washer (DAW) cavity will be used for the medium-velocity part of the accelerator, and muons will be accelerated from =
= 0.3 to 0.7 with the operating frequency of 1.296 GHz. Machining, brazing, and low-power measurements of a prototype cell reflecting the design of the first tank of DAW were performed to identify fabrication problems. Several problems were identified, such as misalignment of washers during brazing, and some measures will be taken in the actual tank fabrication. In this paper, the results of the prototype cell fabrication will be reported.
Mukai, Yasunobu; Nakamura, Hironobu; Nakamichi, Hideo; Kurita, Tsutomu; Noguchi, Yoshihiko*; Tamura, Takayuki*; Ikegame, Ko*; Shimizu, Junji*
Proceedings of INMM 56th Annual Meeting (Internet), 9 Pages, 2015/07
The PIMS used at Rokkasho Reprocessing Plant can quantify plutonium amount in each process vessel located inside glovebox by means of neutron measurement. Since the PIMS is not used for the neutron coincidence counting, it is very important to maintain that those constants meet the actual process condition. PIMS was calibrated in 2006, and then JNFL has been started to measure the Pu amount directly in each glovebox for the purpose of facility NMA. However, it was found that PIMS counting was unexpectedly and continuously increased during long time of inter-campaign. In order to find out the main cause, JAEA and JNFL jointly conducted several investigations. In the investigations, correctness of system parameters and relevant constants, behavior of the neutron generation when MOX powder is stored in actual glovebox for a long time (to see O/M and moisture change) and the behavior focused on the relation between MOX powder and light element using inside glovebox (fluorine is included in the PTFE which is used in many gloveboxes as packing of instruments) were experimentally confirmed using MOX powder in PCDF. As a result, since the same behavior happened in the actual PIMS was confirmed in the testing environment in which MOX powder coexists with fluorine, it is concluded that the main potential cause of PIMS is the increasing of the probability of (,
) reactions by a contact between PTFE and MOX powder.
Tamura, Junji*; Kido, Hiroko*; Hato, Shinji; Homma, Toshimitsu
JAEA-Research 2008-103, 94 Pages, 2009/03
The plume models are used in probabilistic accident consequence assessment (PCA) codes due to cost and time savings. The PCA code, OSCAAR developed by JAERI (Present; JAEA) uses the puff model to calculate atmospheric transport and dispersion. In order to investigate uncertainties involved with the structure of the atmospheric dispersion/deposition model in OSCAAR, we have introduced the more sophisticated computer codes that included regional meteorological model RAMS and atmospheric transport model HYPACT, and comparative analyses between OSCAAR and RAMS/HYPACT have been performed. In this study, model verification of OSCAAR and RAMS/HYPACT was conducted using data of long term atmospheric diffusion experiments, which were carried out in Tokai-mura, Ibaraki-ken. The predictions by models and the results of the atmospheric diffusion experiments indicated relatively good agreements. And it was shown that model performance of OSCAAR was the same degree as it of RAMS/HYPACT.
Naganawa, Hirochika; Shimojo, Kojiro; Mitamura, Hisayoshi; Sugo, Yumi; Noro, Junji*; Goto, Masahiro*
Solvent Extraction Research and Development, Japan, 14, p.151 - 159, 2007/00
A compound having diglycol amic acid frame, DODGAA, has been synthesized as a new "green" extractant for lanthanides. The new extractant composed, hydrogen, oxygen, and nitrogen atoms is fully combustible to gases without solid waste and its solubility in water is found to be very low. These properties enable us to avoid the burden of industrial waste produced by the incineration of deteriorated extractant and the risk of aquatic environmental pollution. In the extraction ability for lanthanide ions and the ability for their mutual separation, DODGAA is much superior to carboxykic acid type extractants, such as Versatic10, that can also be completely combustible. The extraction and separation performance of DODGAA is comparable to that of organophosphorus extractants, such as PC-88A and DEHPA, that are widely used in current industry but less "green".
Omori, Junji*; Kitamura, Kazunori*; Araki, Masanori; Oono, Isamu*; Shoji, Teruaki
JAERI-Tech 2002-053, 86 Pages, 2002/07
no abstracts in English
Ejiri, Mitsuru*; Kitamura, Kazunori*; Araki, Takao*; Omori, Junji*; Asano, Shiro*; Hayakawa, Atsuro*; Shibama, Yusuke; Masaki, Kei; Sakasai, Akira
no journal, ,
In the operation of tokamak, such loads as electromagnetic and seismic are assumed to be imposed on the vacuum vessel (VV), and not a little thermal expansion takes place when VV is baked. The gravity support leg (GS) has to support the loads described above in addition to the dead weight of VV including in-vessel components and compensate deformation. The GS is equipped with plate spring (PS) to have both stiffness and flexibility. In this study, the buckling strength of the PSs was evaluated. The effect of the initial imperfection of the PSs which is assumed to result from machining or welding process on the buckling strength was also studied. It is concluded that GS has sufficient buckling strength against assumed initial imperfections.
Naganawa, Hirochika; Yanase, Nobuyuki; Nagano, Tetsushi; Mitamura, Hisayoshi; Noro, Junji*
no journal, ,
no abstracts in English
Suhara, Junji*; Okamoto, Shuhei*; Mori, Shigenobu*; Kitamura, Seiji
no journal, ,
no abstracts in English