Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Asamori, Koichi; Sueoka, Shigeru; Komatsu, Tetsuya; Ogata, Manabu; Uchida, Mao; Nishiyama, Nariaki; Tanaka, Kiriha; Kobayashi, Tomoharu; Mitsuguchi, Takehiro; Murakami, Osamu; et al.
JAEA-Review 2025-035, 29 Pages, 2025/10
JAEA-Review-2025-035.pdf:1.12MB
This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of high-level radioactive waste (HLW) in Japan Atomic Energy Agency (JAEA), in fiscal year 2025. The objectives and contents of this research are described in detail based on the JAEA 4th Medium- and Long-term Plan (fiscal years 2022-2028). In addition, the background of this research is described from the necessity and the significance for site investigation and safety assessment, and the past progress. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.
Watanabe, Takahiro; Kida, Fukuka; Yamasaki, Shinichi*; Yamagishi, Hiroyuki*; Ochiai, Shinya*; Matsunaka, Tetsuya*; Nara, Fumiko; Tsuchiya, Noriyoshi*
Bunseki Kagaku, 74(10-11), p.611 - 619, 2025/10
Bromine and iodine contents in geological samples can be used as useful tools to understand various environmental phenomena such as past sea-level changes, geological uplift and subsidence, as well as marine incursion to the inland due to paleo tsunami and storm surges. In this study, we measured bromine and iodine contents in possible standard materials and lake sediment samples using the WDXRF at Tono Geoscience Center and polarizing EDXRF at Tohoku University. We compared both results and confirmed that the WDXRF method for Bromine and iodine content determinations can provide the reliable results.
Niwa, Masakazu; Shimada, Akiomi; Asamori, Koichi; Sueoka, Shigeru; Komatsu, Tetsuya; Nakajima, Toru; Ogata, Manabu; Uchida, Mao; Nishiyama, Nariaki; Tanaka, Kiriha; et al.
JAEA-Review 2024-035, 29 Pages, 2024/09
JAEA-Review-2024-035.pdf:1.24MB
This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of high-level radioactive waste (HLW) in Japan Atomic Energy Agency (JAEA), in fiscal year 2024. The objectives and contents of this research are described in detail based on the JAEA 4th Medium- and Long-term Plan (fiscal years 2022-2028). In addition, the background of this research is described from the necessity and the significance for site investigation and safety assessment, and the past progress. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.
Takeuchi, Tetsuya*; Honda, Fuminori*; Aoki, Dai*; Haga, Yoshinori; Kida, Takanori*; Narumi, Yasuo*; Hagiwara, Masayuki*; Kindo, Koichi*; Karube, Kosuke*; Harima, Hisatomo*; et al.
Journal of the Physical Society of Japan, 93(4), p.044708_1 - 044708_10, 2024/04
Times Cited Count：0 Percentile：0.00(Physics, Multidisciplinary)
Sb
Kitaori, Aki*; Kanazawa, Naoya*; Kida, Takanori*; Narumi, Yasuo*; Hagiwara, Masayuki*; Kindo, Koichi*; Takeuchi, Tetsuya*; Nakamura, Ai*; Aoki, Dai*; Haga, Yoshinori; et al.
Journal of the Physical Society of Japan, 92(2), p.024702_1 - 024702_6, 2023/02
Times Cited Count：2 Percentile：30.70(Physics, Multidisciplinary)
=1/2 one-dimensional Ising-like antiferromagnet BaCo
VO
in transverse magnetic fieldsOkutani, Akira*; Onishi, Hiroaki; Kimura, Shojiro*; Takeuchi, Tetsuya*; Kida, Takanori*; Mori, Michiyasu; Miyake, Atsushi*; Tokunaga, Masashi*; Kindo, Koichi*; Hagiwara, Masayuki*
Journal of the Physical Society of Japan, 90(4), p.044704_1 - 044704_9, 2021/04
Times Cited Count：5 Percentile：50.53(Physics, Multidisciplinary)Si single crystal grown by the flux methodTakeuchi, Tetsuya*; Haga, Yoshinori; Taniguchi, Toshifumi*; Iha, Wataru*; Ashitomi, Yosuke*; Yara, Tomoyuki*; Kida, Takanori*; Tahara, Taimu*; Hagiwara, Masayuki*; Nakashima, Miho*; et al.
Journal of the Physical Society of Japan, 89(3), p.034705_1 - 034705_15, 2020/03
Times Cited Count：0 Percentile：0.00(Physics, Multidisciplinary)SiTakeuchi, Tetsuya*; Yara, Tomoyuki*; Ashitomi, Yosuke*; Iha, Wataru*; Kakihana, Masashi*; Nakashima, Miho*; Amako, Yasushi*; Honda, Fuminori*; Homma, Yoshiya*; Aoki, Dai*; et al.
Journal of the Physical Society of Japan, 87(7), p.074709_1 - 074709_14, 2018/07
Times Cited Count：14 Percentile：63.23(Physics, Multidisciplinary)(Ge
Si
) based on the doniach phase diagramIha, Wataru*; Yara, Tomoyuki*; Ashitomi, Yosuke*; Kakihana, Masashi*; Takeuchi, Tetsuya*; Honda, Fuminori*; Nakamura, Ai*; Aoki, Dai*; Gochi, Jun*; Uwatoko, Yoshiya*; et al.
Journal of the Physical Society of Japan, 87(6), p.064706_1 - 064706_14, 2018/06
Times Cited Count：20 Percentile：72.62(Physics, Multidisciplinary)Mannan, M. A.*; Baba, Yuji; Kida, Tetsuya*; Nagano, Masamitsu*; Noguchi, Hideyuki*
Materials Sciences and Applications, 6(5), p.353 - 359, 2015/05
The synthesis and structure of hexagonal boron carbonitride (h-BCN) film on polycrystalline diamond surface were reported. Polycrystalline diamond and/or diamond-like carbon were first fabricated on Si (100) and then it was used as substrate. The deposition was performed by radio frequency plasma enhanced chemical vapor deposition. In order to reduce the content of nitrogen void defects, the deposition was performed at the high temperature of 950
C under the working pressure of 2.6 Pa. The typical sample with atomic composition of B
C
N
O
in the h-BCN lattice was characterized by X-ray photoelectron spectroscopy. The fine structure of the film was studied by near-edge X-ray absorption fine structure (NEXAFS) measurements. The B K-edge and N K-edge of NEXAFS spectra revealed that the synthesized h-BCN film has the ideal honeycomb-like BN
configuration without nitrogen void defects.
Mannan, M. A.*; Baba, Yuji; Hirao, Norie; Kida, Tetsuya*; Nagano, Masamitsu*; Noguchi, Hideyuki*
Materials Sciences and Applications, 4(5A), p.11 - 19, 2013/05
Hexagonal nano-crystalline boron carbonitride (h-BCN) films grown on Si (100) substrate have been investigated. The films were synthesized by radio frequency plasma enhanced chemical vapor deposition using tris-dimethylamino borane as a precursor. Formation of the nano-crystalline h-BCN compound has been confirmed by X-ray diffraction analysis. The films composed of B, C, and N atoms with different B-N, B-C, C-N chemical bonds in forming the sp2-BCN atomic configuration studied by X-ray photoelectron spectroscopy. Orientation and local structures of the h-BCN hybrid were studied by near-edge X-ray absorption fine structure (NEXAFS) measurements. The dominant presence of 
and 
resonance peaks of the sp2-hybrid orbitals in the B K-edge NEXAFS spectra revealed the formation of the flat sp2-BCN configuration around B atoms which are bound with three nitrogen atoms.
Nemoto, Yoshiyuki; Keyakida, Satoshi*; Uchimoto, Tetsuya*; Takaya, Shigeru; Tsukada, Takashi
International Journal of Applied Electromagnetics and Mechanics, 35(2), p.123 - 139, 2011/02
Times Cited Count：1 Percentile：10.68(Engineering, Electrical & Electronic)This paper presents a study conducted to develop a diagnostic system that can detect IASCC precursors in stainless steels by measuring the magnetic properties of the material. The eddy current method and alternating current (AC) magnetization method were used, as these will be more practical for use in actual reactors. Probes were developed for these measurement methods, providing sufficient tolerance for environments in nuclear reactors. An attempt was also made to improve spatial resolution by manufacturing a smaller probe. A sensor system was designed for remote control, performance tests were conducted by measuring neutron-irradiated specimens and mock specimens, and magnetic data were evaluated by comparing the IASCC susceptibility of the specimens. It was proved that the sensor system developed in this study is capable of detecting IASCC precursors. Further developments necessary for application in actual nuclear reactors and the mechanism of correlation between magnetic properties and IASCC susceptibility were also discussed.
Mannan, M. A.; Baba, Yuji; Kida, Tetsuya*; Nagano, Masamitsu*; Shimoyama, Iwao; Hirao, Norie; Noguchi, Hideyuki*
Thin Solid Films, 519(6), p.1780 - 1786, 2011/01
Times Cited Count：21 Percentile：62.11(Materials Science, Multidisciplinary)Orientation of BCN hybrid films synthesized on Ni (111) and Ti substrates by radio frequency plasma enhanced chemical vapor deposition has been investigated. Formation of the 
-BCN hybrids was confirmed by X-ray diffraction. Raman spectra also suggested the presence of graphite-like -BCN hybrid bonds. Orientation and local structures of the films were studied by the near-edge X-ray absorption fine structure (NEXAFS) measurements using synchrotron radiation. The B K-edge NEXAFS spectra revealed the preferred formation of the -BCN hybrid configuration around the B atoms like-BN on Ni (111). It was revealed that the BCN film is parallel to the surface on Ni(111). On the other hand, the film is randomly oriented on Ti surface. It was suggested that the chemical reactivity of the metal surface affects the orientation of the BCN hybrid film.
Oikawa, Ryota*; Uchimoto, Tetsuya*; Takagi, Toshiyuki*; Urayama, Ryoichi*; Nemoto, Yoshiyuki; Takaya, Shigeru; Keyakida, Satoshi*
International Journal of Applied Electromagnetics and Mechanics, 33(3-4), p.1303 - 1308, 2010/10
Times Cited Count：5 Percentile：33.97(Engineering, Electrical & Electronic)This paper discusses feasibility of non-linear eddy current method to evaluate material degradations of austenitic stainless steels associated with irradiation assisted stress corrosion cracking (IASCC). For the purpose, tensile test at elevated temperature was conducted using model alloys simulating radiation induced segregation (RIS), then magnetization curve of the specimens was measured by vibrating sample magnetometer (VSM), and microstructure of magnetization was observed by magnetic force microscopy (MFM). Moreover non-linear eddy current method was carried out. It was shown that the 3rd higher harmonic ration of the pick-up signal would relate to nominal strain of the specimens.
Mannan, M. A.; Noguchi, Hideyuki*; Kida, Tetsuya*; Nagano, Masamitsu*; Hirao, Norie; Baba, Yuji
Thin Solid Films, 518(15), p.4163 - 4169, 2010/05
Times Cited Count：32 Percentile：73.59(Materials Science, Multidisciplinary)Hexagonal boron carbonitride (h-BCN) hybrid films have been synthesized on highly oriented pyrolytic graphite by radiofrequency plasma enhanced chemical vapor deposition using tris-(dimethylamino)borane as a single-source molecular precursor. The films were characterized by X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS) and Raman spectroscopic measurements. XPS measurement showed that the B atoms were bonded to C and N atoms to form the BCN hybrid chemical environment. The atomic composition estimated from the XPS of the typical sample was found to be almost B1C1N1. NEXAFS spectra of the B K-edge and the N K-edge had the peaks due to the and resonances of hybrid orbitals implying the existence of the 
hybrid configurations of h-BCN around the B atoms.
Kida, Tetsuya*; Shigezumi, Kazuya*; Mannan, M. A.*; Akiyama, Morito*; Baba, Yuji; Nagano, Masamitsu*
Vacuum, 83(8), p.1143 - 1146, 2009/05
Times Cited Count：18 Percentile：55.79(Materials Science, Multidisciplinary)Boron carbonitride films were deposited on Si substrates by plasma-enhanced chemical vapor deposition using a powdered precursor of trimethylamine borane. The effect of using different carrier gasses and microwave powers was investigated. Field emission scanning electron microscopy revealed that the films have a nanofibrous structure with elongated features 20 nm in diameter and 200 nm in length. Fourier transfer infrared spectroscopy was used to investigate chemical bonding states present in the deposited films. The FT-IR results suggested that the films have multiple chemical bonding states including C-N, B-N, and B-C bonds, as well as oxygen incorporation in the form of B-O bonds. Mixing the powdered precursor with molecular sieve was found to reduce the oxygen content in the films by removing surface adsorbed water from the precursor.
Mannan, M. A.*; Kida, Tetsuya*; Noguchi, Hideyuki*; Nagano, Masamitsu*; Shimoyama, Iwao; Hirao, Norie; Baba, Yuji
Journal of the Ceramic Society of Japan, 117(1364), p.503 - 507, 2009/04
Times Cited Count：12 Percentile：54.39(Materials Science, Ceramics)Oriented hexagonal BCN films were synthesized on Si(100) substrate by radiofrequency plasma enhanced chemical vapor deposition using tris-(dimethylamino)borane as a precursor. The formation of the crystalline hexagonal BCN hybrids was confirmed by FT-IR and XRD. CH
+ H carrier gas increased the C content in the films in comparison with N carrier gas. XPS measurement showed that the films were composed of a variety of B-N, B-C, C-N bonds to form the BCN atomic hybrids. The resonance peak in the B K-edge NEXAFS spectra also indicated the presence of the 
hybrid configuration of B-C-N bonds like BN in h-BN. The resonance peaks suggested the diversity in the bonds in the films. Orientation of the h-BCN hybrids was suggested on the basis of the polarization dependence of NEXAFS.
Takaya, Shigeru; Nemoto, Yoshiyuki; Uchimoto, Tetsuya*; Keyakida, Satoshi*
Nihon AEM Gakkai-Shi, 17(1), p.156 - 161, 2009/03
In a previous study, authors showed experimentally the correlation between leakage magnetic flux density and irradiation assisted stress corrosion cracking susceptibility of high purity model austenitic stainless steels. This study aimed to investigate mechanism of the correlation. Tensile test at elevated temperature and aging test were conducted on materials simulating irradiation-induced segregation, and leakage magnetic flux density was measured before and after these tests in order to study the influence of chemical composition change and lattice defect to leakage magnetic flux density. Furthermore, dependency of magnetic moment on chemical composition and vacancy was evaluated by first principle calculation. As result, it was shown that leakage magnetic flux density of irradiated materials is thought to increase in severe irradiation-induced segregation region with and without vacancy.
Nemoto, Yoshiyuki; Keyakida, Satoshi*; Uchimoto, Tetsuya*; Takaya, Shigeru; Tsukada, Takashi
Hozengaku, 7(4), p.57 - 68, 2009/01
Authors previously reported leakage magnetic flux density measured by flux gate (FG) sensor seems to depend on irradiation assisted stress corrosion cracking (IASCC) susceptibility of neutron irradiated austenitic stainless steels. This study aimed to evaluate possibility to develop diagnostic method to detect symptom of IASCC by more practical methods such as Eddy current method and AC magnetization method. Magnetic properties of neutron irradiated specimens and mockup specimens were studied and dependence on IASCC susceptibility was revealed. Microstructure observation using transmission electron microscope (TEM) was conducted to study magnetic phase formation by radiation induced segregation. It was shown that measurement of magnetic signal changed by magnetic phase formation along grain boundaries caused by radiation induced segregation would be a mechanism of the diagnostic method to detect symptom of IASCC.
Mannan, M. A.*; Nagano, Masamitsu*; Kida, Tetsuya*; Hirao, Norie; Baba, Yuji
Journal of Physics and Chemistry of Solids, 70(1), p.20 - 25, 2009/01
Times Cited Count：55 Percentile：84.39(Chemistry, Multidisciplinary)Boron carbonitride (BCN) films have been synthesized on Si(100) substrate by radio frequency plasma enhanced chemical vapor deposition using Tris-(dimethylamino)borane (TDMAB) as a precursor. The formation of the sp-bonded BCN phase was confirmed by Fourier transform infrared spectroscopy. X-ray photoelectron spectroscopy measurements showed that B atoms were bonded to C and N atoms to form the BCN atomic hybrid configurations. Near-edge X-ray absorption fine structure measurements indicated that B atoms were bonded not only to N atoms but also to C atoms to form various configurations of sp-BCN atomic hybrids. The polarization-dependence of NEXAFS suggested that the predominant hybrid configuration of sp-BCN films oriented in the direction perpendicular to the Si substrate.
