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Journal Articles

Cycloidal magnetic ordering in noncentrosymmetric EuIrGe$$_3$$

Matsumura, Takeshi*; Tsukakoshi, Mitsuru*; Ueda, Yoshihisa*; Higa, Nonoka*; Nakao, Akiko*; Kaneko, Koji; Kakihana, Masashi*; Hedo, Masato*; Nakama, Takao*; Onuki, Yoshichika*

Journal of the Physical Society of Japan, 91(7), p.073703_1 - 073703_5, 2022/07

 Times Cited Count:6 Percentile:76.56(Physics, Multidisciplinary)

Journal Articles

Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex, 2; Neutron scattering instruments

Nakajima, Kenji; Kawakita, Yukinobu; Ito, Shinichi*; Abe, Jun*; Aizawa, Kazuya; Aoki, Hiroyuki; Endo, Hitoshi*; Fujita, Masaki*; Funakoshi, Kenichi*; Gong, W.*; et al.

Quantum Beam Science (Internet), 1(3), p.9_1 - 9_59, 2017/12

The neutron instruments suite, installed at the spallation neutron source of the Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex (J-PARC), is reviewed. MLF has 23 neutron beam ports and 21 instruments are in operation for user programs or are under commissioning. A unique and challenging instrumental suite in MLF has been realized via combination of a high-performance neutron source, optimized for neutron scattering, and unique instruments using cutting-edge technologies. All instruments are/will serve in world-leading investigations in a broad range of fields, from fundamental physics to industrial applications. In this review, overviews, characteristic features, and typical applications of the individual instruments are mentioned.

Journal Articles

Hydrogen concentration behavior in the IHTS of Monju

Ito, Kazuhiro; Tanabe, Hiromi; Kaneko, Yoshihisa; Kagota, Eiichi; Takahashi, Yasuo

Proceedings of 2013 International Congress on Advances in Nuclear Power Plants (ICAPP 2013) (USB Flash Drive), 10 Pages, 2013/04

The Monju is equipped with two types of hydrogen-meters to detect water leakage in steam generators. Since they are so highly-sensitive as to detect minor water leak from a steam generator tube, they sometimes detect hydrogen concentration increases at plant operational condition changes such as start-up without any water leak. No water leak was experienced during one year operation of the Startup Test up to 40% in 1995, although hydrogen concentration sometimes increased at plant operational condition changes. The H behavior of Monju IHTS during the previous Startup Test was examined and the following knowledge was obtained: The in-sodium H behaves in parallel with the IHTS sodium temperature. In-cover-gas H behavior is more complicated and sensitive to plant operational condition changes such as plant load changes than the in-sodium one. Both types of H-meters underwent a certain degree of zero level drift during one year operation.

Journal Articles

Restart of protype FBR "Monju" after long-term shut-down

Nakai, Satoru; Kaneko, Yoshihisa; Mukai, Kazuo

Hozengaku, 9(4), p.44 - 49, 2011/01

The sodium leak accident in a secondary main cooling system of prototype fast breeder reactor Monju on December 8th in 1995, and the Monju has shut down for 14 and half years since that. JAEA improved the safety by investigating the sodium leakage accident, taking countermeasures such as better understanding by the local's, improvement of operation. In the maintenance field, the confirmation of Monju systems and components integrity, systems improvement as sodium leak countermeasures, introduction of the maintenance program to resolve maintenance problems. Monju restarted on May 6th 2010 after the confirmation of restart readiness by safety authorities and the core confirmation test which is first test after restart was continued to July 22nd as planned.

JAEA Reports

Experiments on the water leak detection system in the 50MW steam generator test facility (14); General report about material test of nickel membrane

Kaneko, Yoshihisa*; Nishikimi, Masakazu*; Shirato, Seiichi*; Morimoto, Makoto*; *

PNC TN941 85-25, 347 Pages, 1985/02

PNC-TN941-85-25.pdf:45.26MB

Nickel membrane type hydrogen meter is used to detect earlier water leakage from heat transfer tubes in the steam generator for Fast Breeder Reactor. The nickel membrane is one of the most important pieces for the hydrogen meter and is used under the severe condition such as high temperature of 500$$^{circ}$$C so that it may happen that corrosion, conversion in microstructure and shortage of mechanical strength etc. Various material tests for 11 kinds of nickel membranes used in the test facility for a longterm were done and following results were obtained. (1)A little corrosion was observed for the nickel membrane used over a long term. (2)The microstructure of the nickel membrane have been converted to recrystal microstructure. The microstructure for the weld is dendritic structure and it has atendency of the growth of crystal grain by the welding heat. (3)The tensile strength of the nickel membrane is decreased slightly, but, it keeps sufficiently the permissible tensile strength. The hardness of the nickel membrane have been decreased to the hardness of annealing material. (4)Iron, chromium and manganese etc. were attached to the surface of the nickel membrane and especiallyy the manganese soaked into several micron in the nickel membrane. But, these deposits haven't any effect for the hydrogen meter. (5)The leak position on the nickel membrane was found in the welding side between the nickel membrane and the vacuum pipe (made of stainless steel). Then, one of important factors having an influence on the membrane's life may be the welding.

JAEA Reports

Experiments on the water leak detection system in the 50MW steam generator test facility (13); Data of water leak simulation tests

Kaneko, Yoshihisa*; Nishikimi, Masakazu*; Shirato, Seiichi*; Morimoto, Makoto*; *

PNC TN941 85-24, 194 Pages, 1985/02

PNC-TN941-85-24.pdf:10.16MB

Series of tests on the water leak detection system have been conducted in the 50MW Steam Generator Test Facility since December 1974. This report is data of water leak simulation tests (water or hydrogen injection tests) which were carried out until November 1983 since May 1978. These data (response of water leak detector) are recorded in magnetic tape and it is easy to change scale and soon.

JAEA Reports

Experiments on the water leak detection system in the 50MW steam generator test facility (10); Water leak simulation test $$cdot$$ Water leak alarm system

Shirato, Seiichi*; Kaneko, Yoshihisa*; Nishikimi, Masakazu*; Morimoto, Makoto*; Matsumoto, Shigeharu*; Motonaga, Tsutsuji*; Imai, Hiroshi*; Fukuda, Toru

PNC TN941 85-23, 193 Pages, 1985/02

PNC-TN941-85-23.pdf:5.61MB

To develop the small leak sodium-water reaction detection system in the steam generator for Fast Breeder Reactor, the series studies on system evaluation tests have been carried out at the 50MW Steam Generator Test Facility. This report deals with hydrogen and injection tests into the sodium outlet pipe from the superheater, test plans and test equipments for hydrogen injection tests into the evaporator, the response performances for the hydrogen meter and oxygen meter, detection ratio for hydrogen and oxygen and the water leak alarm system etc. The test results are summarized as follows: (1)Hydrogen injection tests & water injection tests into the sodium outlet pipe from the superheater were done and the hydrogen & oxygen behaviors were understood. (2)Hydrogen injection tests at the annulus, down-comer and cover-gas region in the evaporator were done and hydrogen behaviors were understood. (3)Hydrogen detection rates depending on hydrogen injection tests & water injection tests were arranged and factors giving the effect on the rate were evaluated. Also, hydrogen transfer times were evaluated. (4)Hydrogen detection rates at the water leakage in the evaporator were evaluated by the comparison of hydrogen injection test results & water injection test results into the sodium out1et pipe from the superheater and hydrogen injection test results into the evaporator. (5)The water leak alarm system by the computor was completed and the validity was confirmed.

JAEA Reports

Experiments on the water leak detection systems in the 50MW steam generator test facility (9); Cold trap efficiency test, hydrogen background concentration test, hydrogen flux through tube test

Kaneko, Yoshihisa*; Nishikimi, Masakazu*; Shirato, Seiichi*; *

PNC TN941 85-22, 142 Pages, 1985/02

PNC-TN941-85-22.pdf:3.57MB

Series of tests on water leak detection system for Monju steam generators have been excuted in the 50MW Steam Generator Test Facility (50MW SGTF). This paper describes the test results about the removal efficiency of hydrogen by the secondary cold trap, the hydrogen background concentration and hydrogen flux through heat transfer tubes to secondary sodium in steam generator (SG) in order to make clear the hydrogen behavior during ordinary plant operation from October in 1976 to July in 1983. Main results from these tests are: (1)The removal efficieney of hydrogen by the cold trap is 70$$sim$$80 percents, but it shows tendency to decrease when difference between hydrogen concentration at cold trap and that in secondary main loop is small. (2)Hydrogen flux through tubes is smaller than the value which is reported in the first report of these series reports. (3)It is found that the hydrogen background concentration in the secondary main loop of 50MW SGTF is thoroughly low. (4)It is estimated that the hydrogen background concentration in the secondary main loop in Monju plant is lower than 169 ppb.

JAEA Reports

Experiments on the water leak detection systems in the 50MW; steam generator test facility (11); Operational experience of hydrogen meter

Shirato, Seiichi*; Kaneko, Yoshihisa*; *; Nishikimi, Masakazu*; *; *; *

PNC TN941 84-136, 258 Pages, 1984/10

PNC-TN941-84-136.pdf:41.93MB

It is necessary to detect the water leak (sodium-water reaction) as fast as possible in a steam generator for liquid metal fast breeder reactor, and hydrogen meter has been developed for detection of water leak. In-sodium hydrogen meter and in-cover gas hydrogen meter have been developed in 50 MW steam generator test facility for the purpose of leak detection system of LMFBR "Monju" plant. This paper reports the development of each hydrogen meter, operational experience and evaluation of performance. Some proposals for design, manufacture, operation and maintenance of "Monju" plant 1eak detection system are also described.

JAEA Reports

Environmental effect test of rupture disk (I)

Kaneko, Yoshihisa*; *; Nishikimi, Masakazu*; *; *

PNC TN941 84-93, 139 Pages, 1984/06

PNC-TN941-84-93.pdf:14.96MB

Rupture disks were tested for a purpose of examination of burst characteristic, corrosion, change of metal formation and mechanical characteristic. Those rupture disks were installed at evaporator (reverse buckling type), superheater (reverse buckling type) and reaction product vessel (tension loaded type) and were used from September, 1975 to January, 1983 at 50 MW steam generator test facility (50 MW SGTF). Main results are the following; (1)Burst pressure of used and unused rupture disks of steam generator and reaction product vessel was lower than the value measured at producted time. But it satisfied specification in purchase. (2)Burst characteristic of rupture disk for steam generator did not Change even after they were used for 10138$$sim$$12387 hours through at the condition of 200$$sim$$430$$^{circ}$$C and 0.7 $$sim$$ 1.4kg/cm$$^{2}$$g. (3)Rupture disks of steam generator and reaction product vessel opened perfectly at burst test. (4)Corrosion was scarcely found. (5)Metal formation and mechanical and physical characteristics of material (Inconel X-750) of rupture disk has changed (age hardnening) through environment effect. (6)If we use Inconel X-750 as rupture disk material for steam generator, we must put in operation after ageing treatment. Otherwise it is desirable to use Inconel 600 or 625 which is not effected by age hardnening and has heatproof and corrosion-resistance characteristics.

Oral presentation

Confirmation of FBR Monju systems and components integrity toward restart after long-term shut down

Nakai, Satoru; Kaneko, Yoshihisa; Uchihashi, Masaya

no journal, , 

Oral presentation

Neutron scattering study on regulated nano space compounds

Kaneko, Koji; Matsuda, Tatsuma; Ishikawa, Yoshihisa*; Kimura, Hiroyuki*; Noda, Yukio; Momma, Koichi*; Izumi, Fujio*

no journal, , 

no abstracts in English

Oral presentation

Maintenance activity of prototype FBR Monju

Nakai, Satoru; Kaneko, Yoshihisa; Uchihashi, Masaya

no journal, , 

FBR can breed fuel and use minor actinide in the radioactive waste as a fuel, so that reduce environmental burden. Monju play a key role in the development of demonstration reactor in the aspects of demonstration of reliable operability and establishment of operation and maintenance method of FBR. In this paper describes the activities towards the establishment of Monju maintenance program and FBR maintenance method.

Oral presentation

Principles of MONJU maintenance; Characteristic of MONJU maintenance and reflection of LWR maintenance experience to FBR

Nakai, Satoru; Nishio, Ryuichi; Uchihashi, Masaya; Kaneko, Yoshihisa; Yamashita, Hironobu*; Yamaguchi, Atsunori*; Aoki, Takayuki*

no journal, , 

A sodium cooled fast breeder reactor (FBR) has unique systems and components and different degradation mechanism from light water reactor (LWR) so that need to establish maintenance technology in accordance with its features. The examination of the FBR maintenance technology is carried out in the special committee for considering the maintenance for Monju established in the Japan Society of Maintenology (JSM). As a result of the study such as extraction of Monju maintenance feature, maintenance technology benchmark between Monju and LWR components and survey of LWR maintenance experience, it is clear that principles of maintenance are same as LWR, necessity of LWR maintenance experience reflection and points to be considered in Monju maintenance. The road map to establish a FBR maintenance technology in the technical aspect became clear and it is vital to acquire operation and maintenance experience of the plant to implement this road map, and to establish a fast reactor maintenance.

Oral presentation

Proton conduction mechanism and phase transition of (Rb,K)$$_{3}$$H(SeO$$_{4}$$)$$_{2}$$

Kiyanagi, Ryoji; Matsuo, Yasumitsu*; Ishikawa, Yoshihisa*; Noda, Yukio*; Ohara, Takashi; Kawasaki, Takuro; Oikawa, Kenichi; Kaneko, Koji; Tamura, Itaru; Hanashima, Takayasu*; et al.

no journal, , 

The materials represented as M$$_{3}$$H(XO$$_{4}$$)$$_{2}$$ (M=alkali metals, X=Se, S) are known to exhibit high protonic conductivities at relatively low temperature. Although the high protonic conductivity is considered to be due to the disorder of the hydrogen bonds in the materials, details have not been well understood. In addition, clarification of the phase transition to the high proton conducting phase is important in order to understand the realization of the high protonic conductivity. In this study, a high temperature neutron structural study was carried out on Rb$$_{3}$$H(SeO$$_{4}$$)$$_{2}$$, and the solid solution of Rb$$_{3-x}$$K$$_{x}$$H(SeO$$_{4}$$)$$_{2}$$ were also investigated by means of conductivity measurements and neutron structural studies. The high temperature neutron structure analyses revealed that the protons in the high proton conducting phase were two dimensionally distributed, which is considered to be the direct observation of the conducting protons. The solid solution exhibited non-linear decreases of the phase transition temperatures as the K concentration increased. The K ions were found to prefer to occupy one of two possible sites, of which occupancies apparently have close relationship with the phase transition temperature.

Oral presentation

Maintenance history and result of the prototype fast breeder reactor "Monju"

Nakai, Satoru; Kaneko, Yoshihisa

no journal, , 

Prototype fast breeder reactor "Monju" accumulated maintenance, the repair experience more than 25 years after a test operation and got the knowledge that became extremely useful for the design of the fast reactor and operation and maintenance in the future. A maintenance program was introduced as a fast reactor power plant at the Stage of Research and Development, and problems such as the maintenance management became clear and examined the way of the maintenance management based on these experiences.

Oral presentation

The Latest status of a TOF single crystal neutron diffractometer SENJU at J-PARC

Ohara, Takashi; Kiyanagi, Ryoji; Nakao, Akiko*; Munakata, Koji*; Ishikawa, Yoshihisa*; Moriyama, Kentaro*; Tamura, Itaru; Kaneko, Koji

no journal, , 

Oral presentation

The Latest status of a TOF single crystal neutron diffractometer SENJU at J-PARC

Ohara, Takashi; Kiyanagi, Ryoji; Nakao, Akiko*; Munakata, Koji*; Ishikawa, Yoshihisa*; Moriyama, Kentaro*; Tamura, Itaru; Kaneko, Koji

no journal, , 

Oral presentation

Current status of the neutron single crystal diffractometer SENJU at MLF/J-PARC

Kiyanagi, Ryoji; Ohara, Takashi; Nakao, Akiko*; Munakata, Koji*; Ishikawa, Yoshihisa*; Moriyama, Kentaro*; Nakamura, Tatsuya; Kaneko, Koji; Tamura, Itaru

no journal, , 

SENJU is a single crystal diffractometer installed at BL18 in MLF in J-PARC, targeting a inorganic materials and small molecular materials as well as magnetic structure analyses. Owning to the high intensity white neutron provided at MLF and many 2-dimentional detectors covering a wide scattering angle, SENJU is able to measure a wide Q-space very efficiently and has conducted many user experiments and proceeded developments of the instrument. 37 detectors surround the sample position of SENJU enabling it to efficiently measure many directions in the reciprocal space, though still there are regions in the reciprocal space which can not be measured. In order to fill the gaps, a new thin type detectors have been installed at SENJU, which realized wider coverage of the scattering angle by 10% and more efficient measurements. The data analysis software, STARGazer, has been upgraded in order for users to access and analyze data after the experiment, without setting up their PCs specifically for the software. The data is stored in the cloud and the software was modified into a web-app. Users, thus can access the data through the internet and analyze the data on their preferred web-browsers. In addition, for the improvement of the measurement efficiency, a multi-crystal measurement, where multiple crystals are simultaneously measured, has been tested and a 3-dimensional total scattering analysis has been also examined.

Oral presentation

Upgrades of a TOF single-crystal neutron diffractometer SENJU for improvement of versatility

Ohara, Takashi; Kiyanagi, Ryoji; Nakao, Akiko*; Munakata, Koji*; Ishikawa, Yoshihisa*; Moriyama, Kentaro*; Tamura, Itaru; Kaneko, Koji

no journal, , 

25 (Records 1-20 displayed on this page)