JOPSS - Search Results

Search Results: Records 1-20 displayed on this page of 31

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Journal Articles

Sodium-cooled Fast Reactors

Ohshima, Hiroyuki; Morishita, Masaki*; Aizawa, Kosuke; Ando, Masanori; Ashida, Takashi; Chikazawa, Yoshitaka; Doda, Norihiro; Enuma, Yasuhiro; Ezure, Toshiki; Fukano, Yoshitaka; et al.

Sodium-cooled Fast Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.3, 631 Pages, 2022/07

https://shop.elsevier.com/books/sodium-cooled-fast-reactors/morishita/978-0-12-824076-2

This book is a collection of the past experience of design, construction, and operation of two reactors, the latest knowledge and technology for SFR designs, and the future prospects of SFR development in Japan. It is intended to provide the perspective and the relevant knowledge to enable readers to become more familiar with SFR technology.

Journal Articles

Beam-transport optimization for cold-neutron spectrometer

Nakajima, Kenji; Kawamura, Seiko; Kikuchi, Tatsuya; Kajimoto, Ryoichi; Takahashi, Nobuaki*; Nakamura, Mitsutaka; Soyama, Kazuhiko; Osakabe, Toyotaka

EPJ Web of Conferences, 83, p.03011_1 - 03011_5, 2015/01

https://doi.org/10.1051/epjconf/20158303011

Times Cited Count：4 Percentile：72.07(Physics, Multidisciplinary)

We report the design of the beam-transport system (especially the vertical geometry) for a cold-neutron disk-chopper spectrometer AMATERAS at J-PARC. Based on the elliptical shape, which is one of the most effective geometries for a ballistic mirror, the design was optimized to obtain, at the sample position, a neutron beam with high flux without serious degrading in divergence and spacial homogeneity within the boundary conditions required from actual spectrometer construction. The optimum focal point was examined. An ideal elliptical shape was modified to reduce its height without serious loss of transmission. The final result was adapted to the construction requirements of AMATERAS. Although the ideas studied in this paper are considered for the AMATERAS case, they can be useful also to other spectrometers in similar situations.

Journal Articles

AMATERAS; A Cold-neutron disk chopper spectrometer

Nakajima, Kenji; Kawamura, Seiko; Kikuchi, Tatsuya; Nakamura, Mitsutaka; Kajimoto, Ryoichi; Inamura, Yasuhiro; Takahashi, Nobuaki; Aizawa, Kazuya; Suzuya, Kentaro; Shibata, Kaoru; et al.

Journal of the Physical Society of Japan, 80(Suppl.B), p.SB028_1 - SB028_6, 2011/05

https://doi.org/10.1143/JPSJS.80SB.SB028

Times Cited Count：125 Percentile：95.68(Physics, Multidisciplinary)

AMATERAS is a cold-neutron disk-chopper spectrometer in MLF, J-PARC. The construction of main part of the spectrometer has been completed in spring of 2009. Soon after that, we have started the commissioning work on AMATERAS. The performance of AMATERAS has been examined by test experiments in the course of commissioning. In parallel to these works, we have started the user program on AMATERAS from December 2009 and we are getting scientific results from our spectrometer. In this presentation, we will report the current status of AMATERAS including the results of performance tests and some of examples of scientific outputs.

Journal Articles

Pressure-induced antiferromagnetic order in filled skutterudite PrFe $_{4}$ P $_{12}$ studied by single-crystal high-pressure neutron diffraction

Osakabe, Toyotaka; Kuwahara, Keitaro*; Kawana, Daichi*; Iwasa, Kazuaki*; Kikuchi, Daisuke*; Aoki, Yuji*; Kogi, Masafumi*; Sato, Hideyuki*

Journal of the Physical Society of Japan, 79(3), p.034711_1 - 034711_7, 2010/03

https://doi.org/10.1143/JPSJ.79.034711

Times Cited Count：18 Percentile：68.64(Physics, Multidisciplinary)

JAEA Reports

The performance tests used the water scrubber for ruthenium rejection

; ; ; Miyazaki, Hitoshi

JNC TN9410 2002-014, 120 Pages, 2002/11

JNC-TN9410-2002-014.pdf:5.97MB

LEDF (Large Equipment Dismantling Facility) will be constructed for the purpose of decontaminating the high level $alpha solid waste generated in oarai engineering center of JNC. And, main processing process of LEDF is incineration and melting system. LEDF will be intended to reduce the secondary waste that occurs along with the operation of the off gas processing equipment of incineration and melting system. It assumed that we are able to eliminate the adsorption tower using silica gel, if the decontamination factor to volatile ruthenium is able to expect in the packed scrubber that is established to remove harmful gas. Thereupon, we carried out this tests that eliminates the adsorption tower and reduces the secondary waste. The decontamination factor (DF) to the volatile ruthenium by the water scrubber is confirmed in the established institution which is in Tokai Works. However, decontamination factor differs and depends on the ruthenium concentration, harmful gas concentration, washing method and also washing condition. Also, the DF value to the volatile ruthenium in the off gas that occurs from incineration and melting system is obtained, does not exist under the same condition as LEDF. Therefore, the decontamination factor to the volatile ruthenium of the packed scrubber under the operating condition of LEDF is confirmed by this test. The main result of this study is as follows (1) In the examination of the test device specification, the packed scrubber design method was investigated. And, the test device that maintained the resemblance nature with a real machine was produced on the basis of this result. (2) In the result of the ruthenium occurrence condition confirmation test, it was confirmed that the test condition such as the kind of the oxidizer, hold temperature of the oxidization reaction container that produce volatile ruthenium continuously, (3) In the result of the occurrence temperature influence confirmation test, it was confirmed that the ...

JAEA Reports

The rationalization design of large equipment dismantling facility (LEDF); Demonstration test on extinguishing of the cell (II)

; ; Matsumoto, Yoshihiro; ; Kato, Noriyoshi; Miyazaki, Hitoshi; Tanimoto, Kenichi

JNC TN9410 2002-010, 62 Pages, 2002/11

JNC-TN9410-2002-010.pdf:2.37MB

The vaporizer in extinguishing of Large Equipment Dismantling Facility (LEDF)that cost is considering as a plan to cut down as part of a rationalization design highly. When the vaporizer is deleted, it becomes here where liquefied carbon dioxide is emitted in the direct cell, it is necessary to grasp the action and extinguishing performance of the pressure change in the cell by rapid evaporation test of the emitted liquefied carbon dioxide. So pressure action inside the fire laboratory in liquefied carbon dioxide release and a putting out the fire tests due to the combustion time of the combustible were enforced by using the general fire laboratory with Demonstration Test on Extinguishing of the cell (I) in the llth year of Heisei. However, since these tests are after laboratory without airtightness, it needs to grasp the pressure action at the time of liquefied carbon dioxide discharge under the airtight high conditions of having assumed the still more nearly actual cell. The cell (II) Demonstration Test on Extinguishing using the vessel of Sodium Leak Fire and Aerosol test rig (SOLFA-2) container inside of OEC was carried out. The results were as follows. (1)In order to grasp the pressure action of the vessel, the internal pressure of SOLFA-2 was set as -50mmH $_{2}$ O, and emitted liquefied carbon dioxide. Consequently, the tendency for the pressure in the vessel to descend rapidly immediately after liquefied carbon dioxide discharge, and to descend gently-sloping through the process which goes up gradually after that and goes abruptly up for a short time was seen. (2)The process which goes abruptly up in an above-mentioned short time is considered to be the factors with main what some liquefied carbon dioxide emitted in the vessel changed to dry ice, and was deposited taken and sublimating surrounding heat, and evaporating again. (3)It sets to total flooding system and the average minimum temperature in the vessel becomes about -48 $^{circ}$ C, and at ...

JAEA Reports

Rationalization design on large equipment dismantling facility; The cell fire-extinguishing examination (III)

; Matsumoto, Yoshihiro; ; ; Kato, Noriyoshi; Miyazaki, Hitoshi; Tanimoto, Kenichi

JNC TN9410 2002-008, 68 Pages, 2002/07

JNC-TN9410-2002-008.pdf:2.89MB

In order to rationalize for Large Equipment Dismantling Facility (LEDF), the plan of removing vaporizer belong to Cell-fire-extinguishing-system was investigated. When a vaporizer is cut down, It is necessary to grasp a fire-extinguishing performance. The fire-extinguishing performance check examination by liquefaction carbon dioxide in the cell fire-extinguishing examination (I) was carried out in 1999 fiscal year. As the result, The good performance was obtained to polyethylene. But there was the deep-seated fire about a piece of wood. Then, The check items were carbon dioxide (CO $_{2}$ ) concentration and CO $_{2}$ concentration holding time for the deep-seated fire in the cell fire-extinguishing examination (III). The results were as follows; (1)By use of the combustion model in which a piece of wood and cotton were put is lit, temperature inside model, mass reduction, and combustion situation were examined. The model burned remarkably in 3060 min. The peak temperature rise to 680 $^{circ}$ C(MAX), and attained smoldering after (ignition) 70 min. Moreover, in order to determine the generating conditions of a deep-seated fire, the situation of CO $_{2}$ extinguishing after ignition by the time lag of 5090 min were examined. The model around ignition 50 minutes was the most difficult to extinguish, and it turned out that they are the conditions which were most suitable for the deep-seated fire examination model of an exam. (2)In order to decide on CO $_{2}$ concentration and concentration holding time required for fire extinguishing of the deep-seated fire in LEDF, The fire-extinguishing performance was investigated by 40 65% of CO $_{2}$ concentration. Consequently, CO $_{2}$ concentration required for deep-seated fire extinguishing was understood that 60% or more was required when safety was taken into consideration at 50% or more. Moreover, when it was 50% or more of CO $_{2}$ concentration and the holding time of CO $_{2}$ concentration ...

JAEA Reports

The design of the hazardous substance sorting system applicability check of X-ray fluorescence spectrometer

; ; ; Kato, Noriyoshi; Miyazaki, Hitoshi; Tanimoto, Kenichi

JNC TN9410 2002-006, 49 Pages, 2002/07

JNC-TN9410-2002-006.pdf:1.84MB

Construction of LEDF (Large Equipment Dismantling Facility) is being planned by Waste Management Section. This purpose of LEDF is the melting treatment of the radioactive waste in OEC (O-arai Engineering Center) and the waste package in JAERI (O-arai Japan Atomic Energy Research Institute). It is also considered about the disposal plan of the future. Therefore LEDF has the sorting process of waste because of the removal of problematic substances. But that process is conducted using its human eyes. This process needs automatic operation because of high classification accuracy, high reliability, burden reduction of a worker. Then we select EXFS (Energy dispersive X-ray Fluorescence Spectrometer), and conducted the measurement of waste (a sample) with this device. That purpose is to confirm an application as the sorting device. A confirmation result is shown in the following. (1)Sorting performance Measurement is possible without pretreatment, if it is metal. However, sorting is difficult when paint, plating, impurities, etc. are shown in the surface. (2)Measurement position It is necessary to set a gap of the measurement thing from a measurement position to 4㎜ or less. (3)Radiation influence Because the background had risen by the influence of a radiant ray, the distinction of Fluorescence X-ray became difficult. Therefore the distinction of materials became impossible. Aluminum is influenced specially by it. As a conclusion, the application nature of EXFS thing Sorting System is high. But there is a bad influence by radiation. Therefore, difficult is installation into the cell. In order to apply EXFS to LEDF, it is necessary to place it outside the cell and to use as the help of the visual inspection.

JAEA Reports

Rationalization design on large equipment dismantling facility; The cell fire-extinguishing examination I

Donomae, Yasushi; Matsumoto, Yoshihiro; Kikuchi, Yutaka; Kato, Noriyoshi; Miyazaki, Hitoshi; Tanimoto, Kenichi

JNC TN9410 2001-021, 73 Pages, 2002/01

JNC-TN9410-2001-021.pdf:3.91MB

In order to rationalize for Large Equipment Dismantling Facility (LEDF), the plan of removing vaporizer belong to Cell-fire-extinguishing-system was investigated. In this test, in order to study the behavior of pressure in cell, when the liquefaction carbon dioxide (liq-CO $_{2}$ ) is emitted, and the performanee of extinguishing fires, the test of behavior of pressure and the extinguishing fires take effect. Also the extinguishing fires test used water-mist take effect for complement liq-CO $_{2}$ . The results as follows; (1)In the test of behavior of pressure, Liq-CO $_{2}$ was emitted test room under -40mmAq negative pressure. Room pressure was increase about 0.8mmAq/sec at first. After 29sec, the pressure was increase slowly about 0.1mmAq/sec. After 120sec, the increase was drastic about 1.5mmAq/s. (2)In the test of extinguishing fires by liq-CO $_{2}$ , under -40mmAq, Polyethylene and wooden chips + cotton (crib) was burn. Polyethylene was extinguished perfectly, but the embers remained in cribs. While the room pressure was increase about 1.3mmAq/sec for 10sec at first. After 30 sec, the pressure was increase about 1mmAq/sec. On the other hand, the drastic increase of pressure disappeared between 100sec to 120sec by change the nozzle size from 14mm $^{2}$ to 10mm $^{2}$ . (3)In the test of extinguishing fires by water-mist, Cribs was extinguished perfectly, but Polyethylene was extinguished difficulty under the same condition of liq-CO $_{2}$ test. (4)Therefore the results, It's coped with the fire extinguishing and the keeping negative pressure for LEDF cells. Therefore nozzle size is fitted cell volume as changing 14mm $^{2}$ to 10mm $^{2}$ . (5)As the performance of extinguishing fires by liq-CO $_{2}$ , It is necessity the concentration of above 50% CO $_{2}$ for combustibles as cribs, remaining the embers. (6)On the other hand, It is necessity most study for the adoption of water-mist. Therefore water-mist was not effective for polyethylene, and it needed water ...