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JAEA Reports

Research report on information of the Nuclear Ship "MUTSU" (Contract research)

Aomori Research and Development Center

JAEA-Review 2022-039, 36 Pages, 2023/02


In order to use for the consideration of floating nuclear power plant, results of survey about actual process and literature are summarized in this report.

JAEA Reports

Consideration on roles and relationship between observations/measurements and model predictions for environmental consequence assessments for nuclear facilities

Togawa, Orihiko; Okura, Takehisa; Kimura, Masanori

JAEA-Review 2022-049, 76 Pages, 2023/01


Before construction and after operation of nuclear facilities, environmental consequence assessments are conducted for normal operation and an emergency. These assessments mainly aim at confirming safety for the public around the facilities and producing relief for them. Environmental consequence assessments are carried out using observations/ measurements by environmental monitoring and/or model predictions by calculation models, sometimes using either of which and at other times using both them, according to the situations and necessities. First, this report investigates methods, roles, merits/demerits and relationship between observations/measurements and model predictions which are used for environmental consequence assessments of nuclear facilities, especially holding up a spent nuclear fuel reprocessing plant at Rokkasho, Aomori as an example. Next, it explains representative examples of utilization of data on observations/measurements and results on model predictions, and considers points of attention at using them. Finally, the report describes future direction, for example, improvements of observations/measurements and model predictions, and fusion of both them.

Journal Articles

Design of microchannel suitable for packing with anion exchange resins; Uranium separation from seawater containing a large amount of cesium

Ouchi, Kazuki; Tsukahara, Takehiko*; Brandt, A.*; Muto, Yuki*; Nabatame, Nozomi*; Kitatsuji, Yoshihiro

Analytical Sciences, 37(12), p.1789 - 1794, 2021/12

 Times Cited Count:0 Percentile:8.31(Chemistry, Analytical)

We attempted to scale down a separation process of uranium (U) using the microchip column loaded with anion exchange resin to develop safety and waste-reducing separation technique. The ideal separation performance of U was obtained by the properly design of a microchannel. The concentration of U in seawater as a real-world sample could be quantified with the prepared microchip column. It indicates that the microchip column is sufficiently practical. Compared to separation of U with a general column, the column size was successfully scaled down to $$<$$ 1/5000.

Journal Articles

Radiation dose rate effects on the properties of a laser-induced breakdown spectroscopy system developed using a ceramics micro-laser for fiber-optic remote analysis

Tamura, Koji; Oba, Hironori; Saeki, Morihisa; Taguchi, Tomitsugu*; Lim, H. H.*; Taira, Takunori*; Wakaida, Ikuo

Journal of Nuclear Science and Technology, 58(4), p.405 - 415, 2021/04

 Times Cited Count:7 Percentile:78.91(Nuclear Science & Technology)

Radiation dose rate effects on the properties of a compact fiber-optic laser-induced breakdown spectroscopy (LIBS) system with a monolithic Nd:YAG/Cr:YAG composite ceramics were investigated for remote analysis in hazardous environment. To investigate radiation effects on the LIBS signal, properties related to the Nd:YAG laser operation such as oscillation threshold, output energy, oscillation timing, temporal pulse shape, and beam profile were measured as a function of the radiation dose rate from 0 to 10 kGy/hr in view of their influences to the signal. LIBS spectra of zirconium metal were measured under irradiation. Although signal intensity decreased considerably by irradiation, informative spectra were well obtained even at the maximum radiation dose rate. From the comparison of the LIBS-related parameters among the laser properties, signal reduction was mainly ascribed to the pulse energy reduction. Scintillation emission spectra were also measured from the ceramics during the irradiation, where the signal intensity increased linearly with the dose rate. The results show that the developed system.

Journal Articles

Implementation of a low-activation Au-In-Cd decoupler into the J-PARC 1 MW short pulsed spallation neutron source

Teshigawara, Makoto; Ikeda, Yujiro; Oi, Motoki; Harada, Masahide; Takada, Hiroshi; Kakishiro, Masanori*; Noguchi, Gaku*; Shimada, Tsubasa*; Seita, Kyoichi*; Murashima, Daisuke*; et al.

Nuclear Materials and Energy (Internet), 14, p.14 - 21, 2018/01

 Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)

We developed an Au-In-Cd (AuIC) decoupler material to reduce induced radioactivity instead of Ag-In-Cd one, which has a cut off energy of 1eV. In order to implement it into an actual moderator-reflector assembly, a number of critical engineering issues need to be resolved with regard to large-sized bonding between AuIC and A5083 alloys by the hot isostatic pressing process. We investigated this process in terms of the surface conditions, sizes, and heat capacities of large AuIC alloys. We also show a successful implementation of an AuIC decoupler into a reflector assembly, resulting in a remarkable reduction of radioactivity by AuIC compared to AIC without sacrificing neutronic performance.

Journal Articles

Observation of new neutron-deficient isotopes with Z$$ge$$92 in multinucleon transfer reactions

Devaraja, H. M.*; Heinz, S.*; Beliuskina, O.*; Comas, V. F.*; Hofmann, S.*; Hornung, C.*; M$"u$nzenberg, G.*; Nishio, Katsuhisa; Ackermann, D.*; Gambhir, Y. K.*; et al.

Physics Letters B, 748, p.199 - 203, 2015/09


 Times Cited Count:62 Percentile:96.81(Astronomy & Astrophysics)

Journal Articles

Effects of irradiation on mechanical properties of HIP-bonded reduced-activation ferritic/martensitic steel F82H first wall

Furuya, Kazuyuki; Wakai, Eiichi; Miyamoto, Kenji*; Akiba, Masato; Sugimoto, Masayoshi

Journal of Nuclear Materials, 367-370(1), p.494 - 499, 2007/08

 Times Cited Count:0 Percentile:0.01(Materials Science, Multidisciplinary)

A partial mock-up of a breeding blanket structure made of F82H steel has been successfully fabricated. In this study, microstructural observation and EDX analysis of the HIP interfaces were performed, and effects of irradiation on mechanical properties of the HIP-bonded region were also examined. Neutron irradiation was performed up to about 2 dpa at about 523 K. After the irradiation, tensile test was performed at temperatures of 295 and 523 K. The HIP interfaces possessed many precipitates, and enriched peak spectrum of chromium was detected from the precipitates. In addition, aspect of the spectrum was qualitatively equivalent to that of M$$_{23}$$C$$_{6}$$ in grain boundaries of F82H steel. In result, the HIP boundary has many M$$_{23}$$C$$_{6}$$ which were generally seen in grain boundaries of F82H steel. Rupture did not occur in the HIP interface. In result, it can be mentioned that bondability is maintained under the irradiation and testing conditions. The strength and elongation of the HIP-bonded region decreased somewhat in comparison with the results of an IEA standard steel.

Journal Articles

Development of aluminum (Al5083)-clad ternary Ag-In-Cd alloy for JSNS decoupled moderator

Teshigawara, Makoto; Harada, Masahide; Saito, Shigeru; Oikawa, Kenichi; Maekawa, Fujio; Futakawa, Masatoshi; Kikuchi, Kenji; Kato, Takashi; Ikeda, Yujiro; Naoe, Takashi*; et al.

Journal of Nuclear Materials, 356(1-3), p.300 - 307, 2006/09

 Times Cited Count:9 Percentile:53.7(Materials Science, Multidisciplinary)

We adopted silver-indium-cadmium (Ag-In-Cd) alloy as a material of decoupler for decoupled moderator in JSNS. However, from the heat removal and corrosion protection points of view, the Ag-In-Cd alloy is needed to clad between Al alloys (Al5083). We attempted to obtain good bonding conditions for between Al5083 and ternary Ag-In-Cd alloys by HIPing tests. The good HIP condition was found for small test piece ($$Phi$$20mm). Though a hardened layer due to the formation of AlAg$$_{2}$$ was found in the bonding layer, the rupture strength of the bonding layer was more than 20 MPa, which was the calculated design stress. Bonding tests of a large size piece (200$$times$$200$$times$$30 mm$$^{3}$$), which simulated the real scale, were also performed according to the results of small size tests. The result also gave good bonding and enough required-mechanical-strength, however the rupture strength of the large size test was smaller than that of small one.

Journal Articles

Neutron irradiation effect on mechanical properties of SS/SS HIP joint materials for ITER shielding blankets

Yamada, Hirokazu*; Sato, Satoshi; Mori, Kensuke*; Nagao, Yoshiharu; Takada, Fumiki; Kawamura, Hiroshi

Fusion Engineering and Design, 81(1-7), p.631 - 637, 2006/02

 Times Cited Count:1 Percentile:10.02(Nuclear Science & Technology)

This study estimated the neutron irradiation effect with 1.5 dpa on the mechanical properties of the SS/SS HIP joint materials jointed in the standard HIP joint condition. Results of this study showed that the HIP process in the standard HIP condition could make SS/SS HIP joint material of which tensile properties was equivalent to that of the SS base material. In addition, the effect of surface roughness at the HIP joint material on the mechanical properties of SS/SS HIP joint material was estimated.

Journal Articles

Key achievements in elementary R&D on water-cooled solid breeder blanket for ITER test blanket module in JAERI

Suzuki, Satoshi; Enoeda, Mikio; Hatano, Toshihisa; Hirose, Takanori; Hayashi, Kimio; Tanigawa, Hisashi; Ochiai, Kentaro; Nishitani, Takeo; Tobita, Kenji; Akiba, Masato

Nuclear Fusion, 46(2), p.285 - 290, 2006/02

 Times Cited Count:2 Percentile:7.11(Physics, Fluids & Plasmas)

This paper presents significant progress in R&D of key technologies on the water-cooled solid breeder blanket for the ITER-TBM in JAERI. By the improvement of heat treatment process for blanket module fabrication, a fine-grained microstructure of F82H, can be obtained by homogenizing it at 1150 $$^{circ}$$C followed by normalizing at 930 $$^{circ}$$C after the HIP process. Moreover, a promising bonding process for a tungsten armor and an F82H structural material was developed by using a uniaxial hot compression without any artificial compliant layer. Also, it has been confirmed that a fatigue lifetime correlation, which was developed for ITER divertor, can be applicable for F82H first wall mock-up. As for R&D on a breeder material, Li$$_{2}$$TiO$$_{3}$$, the effect of compression loads on thermal conductivity of pebble beds has been clarified. JAERI have extensively developed key technologies for ITER-TBM, and now steps up into an engineering R&D stage, where integrated performance of TBM structures will be demonstrated by scalable mock-ups.

Journal Articles

Cladding technique for development of Ag-In-Cd decoupler

Teshigawara, Makoto; Harada, Masahide; Saito, Shigeru; Kikuchi, Kenji; Kogawa, Hiroyuki; Ikeda, Yujiro; Kawai, Masayoshi*; Kurishita, Hiroaki*; Konashi, Kenji*

Journal of Nuclear Materials, 343(1-3), p.154 - 162, 2005/08

 Times Cited Count:10 Percentile:56.94(Materials Science, Multidisciplinary)

For decoupled and poisoned moderator, a thermal neutron absorber, i.e., decoupler, is located around the moderator to give neutron beam with a short decay time. A B4C decoupler is already utilized, however, it is difficult to use in a MW class source because of He void swelling and local heating by (n,a) reaction. Therefore, a Ag-In-Cd (AIC) alloy which gives energy-dependence of macroscopic neutron cross section like that of B$$_{4}$$C was chosen. However, from heat removal and corrosion protection points of view, AIC is needed to bond between an Al alloy (A6061-T6), which is the structural material of a moderator. An AIC plate is divided into a Ag-In (15wt%) and Ag-Cd (35wt%) plate to extend the life time, shorten by burn up of Cd. We performed bonding tests by HIP (Hot Isostatic Pressing). We found out that a better HIP condition was holding at 803 K, 100 MPa for 1 h for small test pieces (f20mm). Though a hardened layer is found in the bonding layer, the rupture strength of the bonding layer is more than 20 MPa, which is less than that of the design stress.

Journal Articles

The Neutron irradiation effect on mechanical properties of HIP joint material

Yamada, Hirokazu*; Kawamura, Hiroshi; Tsuchiya, Kunihiko; Kalinin, G.*; Nagao, Yoshiharu; Sato, Satoshi; Mori, Kensuke*

Journal of Nuclear Materials, 335(1), p.33 - 38, 2004/10

 Times Cited Count:8 Percentile:49.02(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

The Characterization of HIP and RHIP consolidated NiAl intermetallic compounds containing chromium particles

Ishiyama, Shintaro; Buchkremer, H. P.*; St$"o$ver, D.*

Nihon Kinzoku Gakkai-Shi, 68(9), p.831 - 837, 2004/09

 Times Cited Count:0 Percentile:0.01(Metallurgy & Metallurgical Engineering)

NiAl intermetallics with dispersive Cr particles consolidated by the Hot Isostaic Press(HIP) and Reactive HIP(RHIP) techniques, has been investigated. Mechanical properties of HIPed and RHIPed materials with various Cr concentrations ranging form 0 to 30 mass.%Cr, were examined at various temperatures. The consolidation temperature of RHIP materials decreases with Cr addition; when RHIPing NiAl+xCr compounds with 25 mass% has attained, remarkable high ductility over 17% elongation and over 400MPa tensile strength at 873K. A very high tensile strength of HIPed NiAl+20wt.%Cr about 600MPa with 10% elongation was achieved at 873K.

Journal Articles

Thermal cycling tests of 1st wall mock-ups with Beryllium/CuCrZr bonding

Uda, Minoru*; Iwadachi, Takaharu*; Uchida, Munenori*; Yamada, Hirokazu*; Nakamichi, Masaru*; Kawamura, Hiroshi

JAERI-Conf 2004-006, p.60 - 65, 2004/03

no abstracts in English

Journal Articles

Finding evolutionary relations beyond superfamilies; Fold-based superfamilies

Matsuda, Keiko*; Nishioka, Takaaki*; Kinoshita, Kengo*; Kawabata, Takeshi*; Go, Nobuhiro

Protein Science, 12(10), p.2239 - 2251, 2003/10

 Times Cited Count:10 Percentile:17.2(Biochemistry & Molecular Biology)

no abstracts in English

Journal Articles

Tensile and impact properties of F82H steel applied to HIP-bond fusion blanket structures

Furuya, Kazuyuki; Wakai, Eiichi; Ando, Masami; Sawai, Tomotsugu; Iwabuchi, Akira*; Nakamura, Kazuyuki; Takeuchi, Hiroshi

Fusion Engineering and Design, 69(1-4), p.385 - 389, 2003/09

 Times Cited Count:21 Percentile:80.02(Nuclear Science & Technology)

In a fusion reactor, a blanket made of a low activation material like F82H is fabricated by solid Hot Isostatic pressing (HIP) joining method. In a previous study, blanket, grain coarsenings were found in a mock-up around HIP-joined region. To verify an effect of the coarsenings on a strength of the HIP-joined region, tensile test and hardness measurement were done. As the results, the tensile strength increased by about 50 MPa, and the elongation decreased by about 4 % in comparison with that of a standard alloy. Though the hardness was almost constant both in the coarsening and a non-coarsening regions, both of these hardness increased by about 5 %. Therefore, it could be judged that change of the tensile property is due to increase of the hardness. On the other hand, tensile and impact tests of a base metal without coarsening resulted in DBTT increase by about 40 K, although the tensile property was nearly equal to that of the joined-region with coarsening. It can be understood that this is the effect of the heat treatments in the fabrication process of the mock-up.

Journal Articles

Strength proof evaluation of diffusion-jointed W/Ta interfaces by small punch test

Li, J.-F.*; Kawai, Masayoshi*; Kikuchi, Kenji; Igarashi, Tadashi*; Kurishita, Hiroaki*; Watanabe, Ryuzo*; Kawasaki, Akira*

Journal of Nuclear Materials, 321(2-3), p.129 - 134, 2003/09

 Times Cited Count:14 Percentile:67.17(Materials Science, Multidisciplinary)

For the development of tantalum-clad tungsten targets for spallation neutron sources, the bonding strength of tantalum-tungsten interface was investigated by means of an easy-to-use and miniaturized small punch (SP) test, in which a punching load is vertically applied to the center of a jointed disk. Cracks initiated and propagated in the tungsten side for all the samples hot-isostatically pressed (HIPed) at temperatures from 1673 to 2073 K, whereas nocrack and debonding were observed in the interface, indicating that the jointed interface is strongly bonded. The re-crystallization of tungsten occurs and results in its strength reduction, consequently the crack-initiating load decreases with HIPing temperature. The finite element analysis of the measured SP testing results shows that the maximum bonding strength can exceed 1000 MPa. The present study shows that SP test is suitable for the strength evaluation of jointed tantalum-tungsten interfaces.

Journal Articles

Silver-indium-cadmium decoupler and liner

Harada, Masahide; Saito, Shigeru; Teshigawara, Makoto; Kawai, Masayoshi*; Kikuchi, Kenji; Watanabe, Noboru; Ikeda, Yujiro

Proceedings of ICANS-XVI, Volume 2, p.677 - 687, 2003/07

As a decoupler material for intense neutron sources, we proposed a new composite material based on the (n,$$gamma$$) reaction, silver-indium-cadmium alloy (AIC), which had lettle helium gas production rate and higher decoupling energy ($$sim$$1eV). We compared an AIC decoupler with Cd and B$$_4$$C decouplers from various viewpoints and finally selected AIC as decoupler and liner materials. In the current design, we adopted AIC of 2.5mm thick with a composition of Ag-35wt%Cd and 0.5mm thick with Ag-15wt%In. A decoupler and a liner can be bonded to structural material (Al-alloy) by HIP for water cooling through Al-alloy. To find the optimal HIP condition, small pieces of Ag-Cd and Ag-In ($$phi$$20$$times$$2mm) were enclosed in Al-alloy capsules ($$phi$$22mm, 3mm thick bottom plate and 1mm thick cap) of several Al-alloys. The optimal condition was found to be 500$$^{circ}$$C with a holding time of 60 minutes under a fixed pressure of 100MPa. Large pieces (Ag-Cd: 200$$times$$200$$times$$2.5mm, Ag-In: 200$$times$$200$$times$$0.5mm, A5083 and A6061: 210$$times$$210$$times$$21mm) were also tested aiming at more realistic size conditions.

Journal Articles

Solid spallation target materials development

Kawai, Masayoshi*; Furusaka, Michihiro; Li, J.-F.*; Kawasaki, Akira*; Yamamura, Tsutomu*; Mehmood, M.*; Kurishita, Hiroaki*; Kikuchi, Kenji; Takenaka, Nobuyuki*; Kiyanagi, Yoshiaki*; et al.

Proceedings of ICANS-XVI, Volume 3, p.1087 - 1096, 2003/07

In order to establish the technique fabricating a thin target slab with a real size, thin tantalum-clad tungsten slab with a hole for a thermocouple was fabricated with the high-precision machinery techniques and the HIP'ing method. The ultrasonic diagnostic showed that tantalum and tungsten bond was perfect. The HIP optimum condition was certified by means of the small punch test as already reported. The electrolytic coating technique in a molten salt was developed to make a thinner tantalum cladding on a tungsten target with a complicated shape, in order to reduce radioactivity from tantalum in an irradiated target.

127 (Records 1-20 displayed on this page)