Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Teshigawara, Makoto; Lee, Y.*; Tatsumoto, Hideki*; Hartl, M.*; Aso, Tomokazu; Iverson, E. B.*; Ariyoshi, Gen; Ikeda, Yujiro*; Hasegawa, Takumi*
Nuclear Instruments and Methods in Physics Research B, 557, p.165534_1 - 165534_10, 2024/12
Times Cited Count:0 Percentile:0.00(Instruments & Instrumentation)At Japanese Spallation Neutron Source in J-PARC, the para-hydrogen fraction was measured by using Raman spectroscopy in-situ for an integrated beam power of 9.4 MWh at 1 MW operation, to evaluate the functionality of the ferric oxyhydroxide catalyst. This result showed that full functionality of the catalyst was retained up to the 1 MW operation. We attempted to study the effect of neutron scattering driven para to ortho-hydrogen back-conversion rate in the absence of the catalyst effect with a bypass line without catalyst. The measured increase of ortho-hydrogen fraction was 0.44% for an integrated beam power of 2.4 MW
h at 500 kW operation, however, which was considered to be due to not only to neutron collisions in cold moderators but also to the high ortho-hydrogen fraction of initially static liquid hydrogen in the bypass line and passive exudation of quasi-static hydrogen in the catalyst vessel to the main loop.
Sumita, Takehiro; Sudo, Ayako; Takano, Masahide; Ikeda, Atsushi
Science and Technology of Advanced Materials; Methods (Internet), 2(1), p.50 - 54, 2022/02
Sanada, Yukihisa; Miyamoto, Kenji*; Ochi, Kotaro; Matsuzaki, Koji*; Ogawa, Toshihiro*; Senga, Yasuhiro*
Kaiyo Riko Gakkai-Shi, 24(2), p.9 - 18, 2018/12
Seven years passed since Fukushima Dai-ichi Nuclear Power Station accident which was caused large amount of radionuclide release to the sea. Elucidation of behavior mechanism of radiocesium in the seabed is required for restarting fishing industry. We developed radiation detection system using the unmanned surface vehicle for in-situ measurement of radiocesium concentration in seabed sediment. This system is able to automatically navigate to measurement point and obtain the radiation data on the bottom sediment. The detector was calibrated by comparing the actual sediment samples. The periodical measurement off-shore the Fukushima Prefecture was performed using developed this system. As these results, distribution of radiocesium concentration was changed due to oceanographic condition. However, radiocesium inventory was tendency to decrease according to radiocesium half-life in measurement area. This system is effective for elucidation of behavior mechanism of radiocesium because it can easily measure the radiocesium concentration in the bottom sediment.
Niunoya, Sumio*; Aoyagi, Kazuhei; Fujita, Tomoo; Shirase, Mitsuyasu*
Dai-44-Kai Gamban Rikigaku Ni Kansuru Shimpojiumu Koenshu (CD-ROM), p.336 - 341, 2016/01
In the Horonobe Underground Research Laboratory, rock mass classification and determination of mechanical properties of rock mass was conducted considering the effect of the density of fractures in the rock mass. In this paper, the authors report the mechanical properties of rock mass detected by plate loading tests and in situ shear tests in the 250 m and 350 m galleries. As a result, the failure criteria based on the result of in situ shear tests provides the most conservative value for the design of support pattern and assessment of stability of the gallery.
Kuwabara, Kazumichi; Sato, Toshinori; Sanada, Hiroyuki; Takayama, Yusuke
JAEA-Research 2015-005, 378 Pages, 2015/07
This report presents the results of following rock mechanical investigations conducted at the -500m Stage. (1) Laboratory tests using cores and block samples obtained at the -500m Stage. (2) In-situ stress measurement using Compact Conical-ended Borehole Overcoring (CCBO) method at the -500m Stage. (3) In-situ stress measurements using Differential Strain Curve Analysis(DSCA) method at the -500m Stage. (4) Development of rock mechanical model.
Takahashi, Masamitsu; Yoneda, Yasuhiro; Inoue, Hirotane*; Yamamoto, Naomasa*; Mizuki, Junichiro
Japanese Journal of Applied Physics, Part 1, 41(10), p.6247 - 6251, 2002/10
Times Cited Count:55 Percentile:84.85(Physics, Applied)An X-ray diffractometer connected with a molecular-beam epitaxy (MBE) system has been constructed for in situ studies on the growing surfaces of III-V compound semiconductors. This diffractometer is based on the (4+2) type and equipped with an axis for rotating the receiving slit about the normal of the slit plane. This additional axis is used to align the resolution of the receiving slit properly for the surface X-ray diffraction measurement. For the alignment of the sample and the whole setup with respect to the X-ray beam, an XYZ-stage and an adjustable base plate are available. X-rays enter and leave the chamber through two cylindrical Be windows welded onto the MBE chamber. A graphite sheet which can be heated up to 250C is placed along the inside of the Be windows to protect the Be windows from being coated with evaporated materials. Preliminary data are presented to demonstrate the feasibility of static and dynamic measurements of growing surfaces using this instrument.
Yamada, Reiji; Snead, L. L.*; Kato, Yudai*
Proceedings of 4th International Energy Agency Workshop on SiCf/SiC Ceramic Composites for Fusion Structural Application, p.175 - 180, 2000/00
no abstracts in English
Suzuki, Motoe
JAERI-Research 94-022, 36 Pages, 1994/10
no abstracts in English
;
JAERI-M 82-191, 72 Pages, 1982/12
no abstracts in English
; ;
Journal of Nuclear Science and Technology, 17(4), p.281 - 290, 1980/00
Times Cited Count:12 Percentile:74.95(Nuclear Science & Technology)no abstracts in English
Kitagaki, Toru
no journal, ,
Zircon dissolution rates under flowing aqueous solutions of pH 0 (HCl), 7 (HO), 14 (NaOH aq) were in-situ measured from the zircon surface change by Phase-shift interferometric microscope.
Shirase, Mitsuyasu*; Jo, Mayumi*; Motoshima, Takayuki*; Niunoya, Sumio*; Nakayama, Masashi; Tanai, Kenji
no journal, ,
no abstracts in English
Morooka, Satoshi; Kawasaki, Takuro; Harjo, S.; Nakada, Nobuo*; Tsukada, Yuki*
no journal, ,
Terasawa, Tomoo; Katsube, Daiki*; Yano, Masahiro; Ozawa, Takahiro*; Tsuda, Yasutaka; Yoshigoe, Akitaka; Asaoka, Hidehito; Suzuki, Seiya
no journal, ,
Hanawa, Satoshi; Hata, Kuniki; Uchida, Shunsuke; Nishiyama, Yutaka
no journal, ,
Water in the primary circuit of Nuclear Power Plants (NPPs) decomposes by radiolysis, then oxidants such as hydrogen peroxide and oxygen are generated as a result. Hydrogen peroxide is one of the major factor for initiation and propagation of stress corrosion cracking (SCC) in structural materials, hence in-situ monitoring of hydrogen peroxide at the point of interest in irradiation field is quite important to assure the integrity of NPPs. Concentration of hydrogen peroxide in irradiation field is governed by energy deposition by neutron and -ray in which the degree of energy is different in locations, while concentration in un-irradiation area decreases due to thermal decomposition. Quantitative evaluation of hydrogen peroxide is, however, available only by analyzing sampled water at present, and therefore in-situ monitoring of hydrogen peroxide at the point of interest becomes quite important. Frequency dependent complex impedance (FDCI) analysis gives characteristics of oxide film on the materials, and it becames clear by recent activities that the low frequency semicircles in Cole-Cole plots shows linear correlation to the concentration of hydrogen peroxide. JAEA is now developing a sensor for in-situ monitoring of hydrogen peroxide applicable to irradiation environment by applying FDCI. The outline and overall schedule of the sensor development will be reported in the presentation.
Mikami, Satoshi; Saito, Kimiaki
no journal, ,
no abstracts in English
Morooka, Satoshi; Harjo, S.
no journal, ,
Morooka, Satoshi; Igawa, Naoki; Sasaki, Miki; Nabatame, Nozomi; Kodama, Katsuaki
no journal, ,