Yamaki, Kenichi*; Kita, Satoshi*; Obayashi, Hironari; Ariyoshi, Gen; Saito, Shigeru; Sasa, Toshinobu
JAEA-Technology 2020-021, 26 Pages, 2021/02
As digitalization of measuring instruments, Programmable Logic Controller is mainly used for controlling large-scale devices, and many test devices are controlled in digital. Together with increase of the data storage capacity, it has become possible to record the measured values over the entire experimental period. By collecting the entire experimental data, it became easy to appropriately record the test environment during the corrosion test of materials and to analyze the changes and transients during continuous operation from various viewpoints. On the other hand, in a long-term test, the large number of measurement data were recorded, which requires long time for data processing and data extraction for analyses. In addition, it is necessary to pay attention to organize the data collected by different data formats. To solve these problems, a processing tool were produced to extract and process the data efficiently from the sequencer installed in the lead-bismuth test device.
Ikushima, Kazuki*; Shibahara, Masakazu*; Kawajiri, Yoshitaka*; Okimi, Yui*; Uchida, Tomoki*; Akita, Koichi*; Suzuki, Hiroshi; Morooka, Satoshi
Nihon Senpaku Kaiyo Kogakkai Ronbumshu, (30), p.123 - 130, 2019/12
In this research, the contour method was applied to measure the residual stress distribution of a bead-on-plate specimen. The measured residual stress distribution was compared with those measured by neutron diffraction method and calculated by thermal elastic plastic finite element analysis. As a result, it was found that the residual stress distribution obtained by these three methods are in good agreement. In addition, the equilibrium of reaction force on cut plane was considered in the contour method to measure residual stresses in asymmetric cutting which is assumed in the measurement of real structures. The proposed method was applied to the measurement of the residual stress in the multi-pass welded joint. The measured results indicated that the proposed method can measure the residual stress distribution in multi-pass welded joint in asymmetric test specimen.
Obayashi, Hironari; Yamaki, Kenichi; Kita, Satoshi; Yoshimoto, Hidemitsu; Wan, T.; Saito, Shigeru; Sasa, Toshinobu
Proceedings of 18th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-18) (USB Flash Drive), p.262 - 274, 2019/08
Construction of an experimental facility using LBE spallation target is under planning in the framework of J-PARC project to understand the compatibility of candidate ADS structural materials under flowing high temperature LBE environment with proton / neutron irradiation. We constructed a mock-up test loop, IMMORTAL to verify the feasibility of a primary cooling system in the target system. Including the layout considering remote maintainability, the same design as the actual JAEA's LBE target is reflected in most devices of IMMORTAL such as an electromagnetic pump (EMP), a heat exchanger and instrumentations. During the integrated tests, the individually developed devices of LBE loop system worked without significant malfunction. Several experimental data to verify the safety analysis model for LBE loop system using RELAP5-3D was acquired by simulation experiment of transient events such as beam over power and decrease of forced cooling.
Sugawara, Takanori; Kita, Satoshi*; Yoshimoto, Hidemitsu*; Okubo, Nariaki
JAEA-Technology 2018-008, 26 Pages, 2018/09
The oxygen sensors to measure the oxygen concentration in liquid LBE (lead-bismuth eutectic) were fabricated and tested for future use in LBE-cooled ADS (accelerator-driven system) or LBE test loops. The following tests were performed; estimation of catalyst application range, freeze seal structure and estimation of gamma-ray irradiation effect. For the estimation of the catalyst application range, it was confirmed that the measurement accuracy became worse in low LBE temperature as the application range became small. For the freeze seal structure, we realized the structure to prevent the LBE leakage with 0.5 MPa pressure condition. For the estimation of gamma-ray irradiation effect, the ex-situ test was carried out and it was observed that there was little effect by 4 MGy gamma-ray irradiation.
Ikushima, Kazuki*; Shibahara, Masakazu*; Nishikawa, Satoru*; Furukawa, Takashi*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi
E-Journal of Advanced Maintenance (Internet), 9(3), p.NT87_1 - NT87_5, 2017/11
Kuroda, Masatoshi*; Kamaya, Masayuki*; Yamada, Teruaki*; Akita, Koichi
Nippon Kikai Gakkai Rombunshu (Internet), 83(852), p.17-00072_1 - 17-00072_7, 2017/07
In order to assess the fatigue damage of austenitic stainless steels by electron backscatter diffraction (EBSD) method more simply and easily, it should be more preferable to use a commercially available general-purpose EBSD analysis software rather than to employ an in-house developed EBSD analysis programme. In the present study, EBSD measurement was performed for Type 316 austenitic stainless steels subjected to cyclic loading, and the applicability of the EBSD parameter relevant to the pattern quality, which could be obtained by the commercial software, to the fatigue damage assessment was discussed by comparing the other EBSD parameter of the averaged local misorientation (Mave), which could be calculated by the in-house developed programme. As a result, the EBSD parameter relevant to the pattern quality, which signified the full width at half maximum (FWHM) of the histogram distribution of the image quality (IQ), was saturated at the beginning stage of the fatigue cycles, while Mave was increased monotonically with the cycles. This suggested that the FWHM of IQ could be useful to detect the initial stage of the fatigue damage, while Mave was suitable for the quantitative evaluation of the fatigue damage. XRD measurement was also carried out for the same samples employed in the EBSD measurement, and the XRD data was compared with the EBSD data to discuss the crystallographic mechanism of the change in the FWHM of IQ. As a result, it was found that the FWHM of the (111) XRD peak correlated well with the FWHM of IQ. Because the (111) plane in fcc metal such as austenitic stainless steel was most preferable for slip system, this implied that the change in the distribution of the pattern quality generated by the fatigue loading could be due to the slip deformation.
Ikushima, Kazuki*; Kitani, Yuji*; Shibahara, Masakazu*; Nishikawa, Satoru*; Furukawa, Takashi*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi
Yosetsu Gakkai Rombunshu (Internet), 35(2), p.75s - 79s, 2017/06
Ikushima, Kazuki*; Shibahara, Masakazu*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi; Nishikawa, Satoru*; Furukawa, Takashi*
Welding in the World, 61(3), p.517 - 527, 2017/05
In this study, first, an analysis method to predict the behaviour of residual stress distribution on shot peening process was proposed. In the proposed method, the load distribution on the collision of shots was modelled, and it was integrated with the dynamic analysis method based on the idealized explicit FEM (IEFEM). The accuracy of the proposed analysis system was confirmed by comparing the stress distribution on the collision of a single shot with the results analyzed by ABAQUS. The thermal elastic plastic analysis method using IEFEM was applied to the analysis of residual stress distribution of multi-pass welded pipe joint. The calculated residual stress distribution was compared with the measured residual stress distribution using X-ray diffraction (XRD). As a result, it was shown that the both welding residual distribution agree well with each other. Considering the calculated welding residual stress distribution, the modification of stress distribution due to shot peening was predicted by the proposed analysis system. As a result, the similar stress distribution with measurement by XRD was obtained in case that a large number of collisions are considered.
Hosokawa, Shinya*; Kimura, Koji*; Yamasaki, Michiaki*; Kawamura, Yoshihito*; Yoshida, Koji*; Inui, Masanori*; Tsutsui, Satoshi*; Baron, A. Q. R.*; Kawakita, Yukinobu; Ito, Shinichi*
Journal of Alloys and Compounds, 695, p.426 - 432, 2017/02
Futakawa, Masatoshi; Naoe, Takashi; Kogawa, Hiroyuki; Haga, Katsuhiro; Okita, Kohei*
Experimental Thermal and Fluid Science, 57, p.365 - 370, 2014/09
A liquid mercury target system for a megawatt-class spallation neutron source is being developed in the world. Proton beam is injected to the mercury target to induce spallation reaction. The moment the proton beams bombard the target, pressure waves are generated in the mercury by the thermally shocked heat deposition. The pressure waves excite the mercury target vessel and negative pressure that may cause cavitation along the vessel wall. Gas-bubbles will be injected into the flowing mercury to mitigate the pressure waves and suppress the cavitation inception. The injected gas-bubbles conditions were examined and the effects were predicted experimentally and theoretically from the viewpoints of macroscopic time-scale and microscopic time-scale, i.e. in the former is dominant the interaction between the structural vibration and the pressure in mercury, and in the later is essential the pressure wave propagation process.
Asari, Keisuke*; Hetland, O. S.*; Fujita, Satoshi*; Itakura, Mitsuhiro; Okita, Taira*
Journal of Nuclear Materials, 442(1), p.360 - 364, 2013/11
Molecular dynamics simulations were conducted using a set of six interatomic potentials for FCC metals that differed only in stacking fault energy (SFE), to clarify the effect of SFE on interactions between a dissociated edge dislocation and a void. There are two different types of interaction mechanism: separate depinning of the individual partial dislocations and almost simultaneous depinning of the combined partial dislocations. The interaction mechanism depends on both the SFE and void size, and changes the absolute value of the critical resolved shear stress (CRSS) and its dependence on the SFE. In the separate depinning case, the CRSS is relatively low and is almost independent of the SFE, while in the simultaneous case, the CRSS is increases with SFE. The void size for which the change in interaction mechanism occurs increases with decreasing SFE.
Yamada, Satoshi*; Kita, Makoto*; Ishimori, Yuu
JAEA-Research 2013-016, 32 Pages, 2013/09
Tottori University and Japan Atomic Energy Agency started a joint study to investigate the effect of hot spring water on the growth of vegetable plants in 2009. The aim of the study is to examine a feasibility of producing a regionally special vegetable with considering the characteristics of the Misasa district, where radon hot springs are historically famous. This report illustrates the intermediate results obtained from the study carried out from 2011 to 2012.  Plant physiological examination: Plant physiological examination revealed the effects of Misasa hot spring water on the growth and mineral contents of vegetable plants.  Middle scale test: Four tasks for the practical application study were specified; (1) Best mineral contents in hot spring water, (2) Treatment of pH of hot spring water, (3) Toxic substances in hot spring water, (4) A protocol and a system structure for water culture. Then, a middle scale system for water culture was developed.
Kikuchi, Tatsuya; Nakajima, Kenji; Kawamura, Seiko; Inamura, Yasuhiro; Yamamuro, Osamu*; Kofu, Maiko*; Kawakita, Yukinobu; Suzuya, Kentaro; Nakamura, Mitsutaka; Arai, Masatoshi
Physical Review E, 87(6), p.062314_1 - 062314_8, 2013/06
A quasi-elastic neutron scattering (QENS) experiment is a particular technique that endeavors to define a relationship between time and space for the diffusion dynamics of atoms and molecules. However, in most cases, analyses of QENS data are model dependent. We have developed a new method for processing QENS data without a specific model, wherein all modes can be described as combinations of the relaxations based on the exponential law. By this method, we can obtain a new distribution function, , which we call the mode distribution function (MDF), to represent the number of relaxation modes and distributions of the relaxation times in the modes. The deduction of MDF is based on the maximum entropy method. We report the first application to experimental data of liquid water. In addition to the two known modes, the existence of a new relaxation mode of water molecules with an intermediate time scale has been discovered.
Hase, Yoshihiro; Akita, Yusuke; Kitamura, Satoshi; Narumi, Issei; Tanaka, Atsushi
Plant Biotechnology, 29(3), p.193 - 200, 2012/06
Ion beams have been used as a mutagen to improve the efficiency of plant mutation breeding. Mutation breeding is sometimes perceived as a random process. In this review, we describe our recent progress in developing a more efficient mutagenesis technique using ion beam irradiation combined with sucrose pretreatment or subsequent re-irradiation. To shorten the time required for breeding new cultivars of cyclamen, we identified anthocyanin biosynthesis genes and examined the effectiveness of PCR screening of irradiated deletion-mutant candidates at early growth stages. We believe this research is a step toward more efficient and controlled mutation breeding using ion beams.
Kitamura, Satoshi; Akita, Yusuke; Ishizaka, Hiroshi*; Narumi, Issei; Tanaka, Atsushi
Journal of Plant Physiology, 169(6), p.636 - 642, 2012/04
In order to identify the anthocyanin-related GST in cyclamen, four candidates of GSTs (CkmGST1 to CkmGST4) were isolated. Phylogenetic analysis indicated that CkmGST3 was closely related to PhAN9, an anthocyanin-related GST of petunia. Expression analysis at different developmental stages of petals revealed that CkmGST3 was strongly expressed in paler pigmented petals than in fully pigmented petals, in contrast to the constitutive expression of the other three candidates during petal development. This expression pattern of CkmGST3 was correlated with those of other anthocyaninbiosynthetic genes such as CkmF3'5'H and CkmDFR2. Molecular complementation of Arabidopsis , a knockout mutant of an anthocyanin-related GST gene, demonstrated that CkmGST3 could complement the anthocyanin-less phenotype of . Transgenic plants that expressed the other three CkmGSTs did not show anthocyanin accumulation. These results indicate CkmGST3 functions in anthocyanin accumulation in cyclamen.
Takahashi, Nobuaki; Shibata, Kaoru; Kawakita, Yukinobu; Nakajima, Kenji; Inamura, Yasuhiro; Nakatani, Takeshi; Nakagawa, Hiroshi; Fujiwara, Satoru; Sato, Taku*; Tsukushi, Itaru*; et al.
Journal of the Physical Society of Japan, 80(Suppl.B), p.SB007_1 - SB007_4, 2011/12
Akita, Yusuke; Kitamura, Satoshi; Hase, Yoshihiro; Narumi, Issei; Ishizaka, Hiroshi*; Kondo, Emiko*; Kameari, Naoko*; Nakayama, Masayoshi*; Tanikawa, Natsu*; Morita, Yasumasa*; et al.
Planta, 234(6), p.1127 - 1136, 2011/12
Yamada, Satoshi*; Kita, Makoto*; Goto, Yukari*; Ishimori, Yuu
JAEA-Research 2011-027, 38 Pages, 2011/11
Tottori University and Japan Atomic Energy Agency started a joint study to investigate the effect of hot spring water on the growth of vegetable plants in 2009. The aim of the study is to examine a feasibility of producing a regionally special vegetable with considering the characteristics of the Misasa district, where radon hot springs are historically famous. This report illustrates the intermediate results obtained from the study carried out from 2009 to 2010. (1) Screening test: Eighteen plants were examined for screening. As the results, Misasa hot spring water used in the water culture enlarged the growths of 14 plants. Lastly, 9 plants were selected as candidate plants for further examinations. (2) Sample preparation: Plants sampled in the water culture were lyophilized and stored in a freezer for nutrio-physiological analyses to select the suitable plant from the 9 plants. (3) Examination in labor-saving cultivation: Preliminary examinations were performed with a large-scale system to establish a practical labor-saving water culture system.
Akita, Yusuke; Ishizaka, Hiroshi*; Nakayama, Masayoshi*; Shimada, Akihiko; Kitamura, Satoshi; Hase, Yoshihiro; Narumi, Issei; Tanaka, Atsushi
Journal of Horticultural Science & Biotechnology, 85(5), p.437 - 443, 2010/09
The flower colour of gra6 (wild-type) is pink-purple in the flower. On the other hand, flowers of gra50 (white-flowered variant) exhibit a white colour in its flower. In this study, the relationship between floral pigmentation and expression of several anthocyanin biosynthesis genes was investigated in gra6 and gra50. The pigments in the flower consist mainly of malvidin 3,5-diglucoside in gra6. White-flowered gra50 possessed lower amounts of anthocyanins, but higher amounts of flavonols compared to gra6. Gene expression analysis demonstrated that expression of the dihydroflavonol 4-reductase gene 2 () was lower in gra50 compared with gra6, whereas the expression of other key genes did not differ greatly. These results suggest that the white-flowered variant of gra50 may result from a defect in expression of the gene.
Takahashi, Nobuaki; Shibata, Kaoru; Sato, Taku*; Kawakita, Yukinobu*; Tsukushi, Itaru*; Metoki, Naoto; Nakajima, Kenji; Arai, Masatoshi
Nuclear Instruments and Methods in Physics Research A, 600(1), p.91 - 93, 2009/02
A time-of-flight crystal-analyzer neutron inelastic scattering spectrometer DNA has been proposed to construct in the MLF of J-PARC. DNA has been designed to have three crystal analyzers, PG(002), Ge(311) and Si(111) at near-backscattering configurations to study dynamics of biomolecules and proteins in wide energy and momentum transfer ranges. In order to develop the Ge(311) analyzer-crystals we have performed neutron beam experiments to check rocking curves on two candidates, i.e., (a) thick hot-pressed wafers and (b) stacked number of thin as-cut wafers, at the MUSASI port, which is a triple-axis instrument, located on the T2 beam line at the JRR-3M guide hall, Tokai, Japan.