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Kato, Masaru*; Zheng, J.*; Deng, Y.*; Saito, Fumie*; Unuma, Yuki*; Oka, Sayuki*; Tamura, Kazuhisa; Yagi, Ichizo*
ACS Catalysis, 15(10), p.7710 - 7719, 2025/04
Times Cited Count:2 Percentile:75.71(Chemistry, Physical)Terunuma, Akihiro; Mimura, Ryuji; Nagashima, Hisao; Aoyagi, Yoshitaka; Hirokawa, Katsunori*; Uta, Masato; Ishimori, Yuu; Kuwabara, Jun; Okamoto, Hisato; Kimura, Yasuhisa; et al.
JAEA-Review 2016-008, 98 Pages, 2016/07
Japan Atomic Energy Agency formulated the plan to achieve the medium-term target in the period of April 2010 to March 2015(hereinafter referred to as "the second medium-term plan"). JAEA determined the plan for the business operations of each year (hereinafter referred to as "the year plan"). This report is that the Sector of Decommissioning and Radioactive Waste Management has summarized the results of the decommissioning technology development and decommissioning of nuclear facilities which were carried out in the second medium-term plan.
Nagai, Ryoji; Hajima, Ryoichi; Shizuma, Toshiyuki; Mori, Michiaki; Akagi, Tomoya*; Kosuge, Atsushi*; Honda, Yosuke*; Araki, Sakae*; Terunuma, Nobuhiro*; Urakawa, Junji*
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1328 - 1330, 2015/09
Accelerator and laser technologies required for laser Compton scattering (LCS) photon source based on an energy-recovery linac (ERL) have been developed at the Compact ERL (cERL) facility. A high-flux, energy tunable, and monochromatic photon source such as the ERL-based LCS photon source is necessary for nondestructive assay of nuclear materials. For the demonstration of the ERL-based LCS photon generation, a laser enhancement cavity was installed at the recirculation loop of the cERL. The electron beam energy, the laser wavelength, and the collision angle are 20 MeV, 1064 nm, and 18
, respectively. The calculated maximum energy of the LCS photons is about 7 keV. A silicon drift detector (SDD) with active area of 17 mm
placed 16.6 m from the collision point was used for observation of the LCS photons. As a result of the measurement, the flux on the detector, central energy, and energy width of the LCS photons were obtained as 1200/s, 6.91 keV, and 81 eV, respectively.
Takahashi, Fumiaki; Sato, Kaoru; Endo, Akira; Ono, Koji*; Ban, Nobuhiko*; Hasegawa, Takayuki*; Katsunuma, Yasushi*; Yoshitake, Takayasu*; Kai, Michiaki*
Health Physics, 109(2), p.104 - 112, 2015/08
Times Cited Count:10 Percentile:59.23(Environmental Sciences)A dosimetry system, named WAZA-ARI, is developed to assess accurately radiation doses to persons from Computed Tomography (CT) examination patients in Japan. Organ doses were prepared to application to dose calculations in WAZA-ARI by numerical analyses using average adult Japanese human models with the Particle and Heavy Ion Transport code System (PHITS). Experimental studies clarified the radiation configuration on the table for some multi-detector row CT (MDCT) devices. Then, a source model in PHITS could specifically take into account for emissions of X-ray in each MDCT device based on the experiment results. Numerical analyses with PHITS revealed a concordance of organ doses with human body size. The organ doses by the JM phantoms were compared with data obtained using previously developed systems. In addition, the dose calculation in WAZA-ARI were verified with previously reported results by realistic NUBAS phantoms and radiation dose measurement using a physical Japanese model. The results implied that analyses using the Japanese phantoms and PHITS including source models can appropriately give organ dose data with consideration of the MDCT device and physiques of typical Japanese adults.
Nagai, Ryoji; Hajima, Ryoichi; Mori, Michiaki; Shizuma, Toshiyuki; Akagi, Tomoya*; Araki, Sakae*; Honda, Yosuke*; Kosuge, Atsushi*; Terunuma, Nobuhiro*; Urakawa, Junji*
Proceedings of 6th International Particle Accelerator Conference (IPAC '15) (Internet), p.1607 - 1609, 2015/06
Accelerator and laser technologies required for laser Compton scattering (LCS) photon source based on an energy-recovery linac (ERL) have been developed at the Compact ERL (cERL) facility. A high-flux, energy tunable, and monochromatic photon source such as the ERL-based LCS photon source is necessary for nondestructive assay of nuclear materials. For the demonstration of the ERL-based LCS photon generation, a laser enhancement cavity was installed at the recirculation loop of the cERL. The electron beam energy, the laser wavelength, and the collision angle are 20 MeV, 1064 nm, and 18 deg., respectively. The calculated maximum energy of the LCS photons is about 7 keV. A silicon drift detector (SDD) with active area of 17 mm
placed 16.6 m from the collision point was used for observation of the LCS photons. As a result of the measurement, the flux on the detector, central energy, and energy width of the LCS photons were obtained as 1200 /s, 6.91 keV, and 81 eV, respectively.
Sato, Kaoru; Takahashi, Fumiaki; Endo, Akira; Ono, Koji*; Hasegawa, Takayuki*; Katsunuma, Yasushi*; Yoshitake, Takayasu*; Ban, Nobuhiko*; Kai, Michiaki*
RIST News, (58), p.25 - 32, 2015/01
The Japan Atomic Energy Agency (JAEA) are now developing WAZA-ARI for improvement of management of exposure doses due to CT examination under the joint research with the Oita University of Nursing and Health Sciences. The trial version of WAZA-ARI has been released on 21 December 2012. In trial version, users can perform dose assessment by using organ dose database based on the average adult Japanese male (JM-103) and female (JF-103) voxel phantoms and a 4 years old female voxel phantom (UFF4). The homepage of WAZA-ARI has been accessed over 1000 times per month and 28421 times by the end of September 2014. We are developing WAZA-ARI version 2 as the extension version of dose calculation functions of WAZA-ARI. WAZA-ARI version 2 will be released by the end of March 2015. In WAZA-ARI version 2. Users can upload dose calculation results to WAZA-ARI version 2 server, and utilize improvement of the dose management of patients and the optimization of CT scan conditions.
Takahashi, Fumiaki; Sato, Kaoru; Endo, Akira; Ono, Koji*; Yoshitake, Takayasu*; Hasegawa, Takayuki*; Katsunuma, Yasushi*; Ban, Nobuhiko*; Kai, Michiaki*
Progress in Nuclear Science and Technology (Internet), 2, p.153 - 159, 2011/10
Computed Tomography (CT) is one of the most useful tools for medical diagnosis, and is becoming a major source of medical exposure in developed countries. Appropriate radiation protection in CT examinations is emphasized by international organizations, such as the International Atomic Energy Agency (IAEA), because the patients receive higher radiation doses than in conventional radiography. Medical staffs can acquire dose information on the conditions of some CT examinations with available dosimetry systems, which had been already developed. These systems utilize datasets of organ and tissue doses, which were derived with Monte Carlo calculations. Methods in computational analyses, however, have been improved, since these calculations had been performed. Then, our new dosimetry system for CT examination, WAZA-ARI, is being developed to estimate radiation dose based upon the state-of-art numerical analyses. Our analysis adopts Particle and Heavy Ion Transport code System (PHITS) coupled with a voxel-type phantom, JM phantom, for the organ dose calculation. PHITS has advantageous to define the model of photon emission from X-ray tube in a CT device for radiation transport calculations. The physique and mass of organs for JM phantom are similar to those for average Japanese male adults. Since the goal of WAZA-ARI is to provide dosimetric information of arbitrary patient, it is important to evaluate uncertainty due to different configurations in human bodies between JM phantom and individual patients. For this purpose, the organ doses are calculated and compared for different human models; another Japanese male adult voxel phantom and the ICRP reference voxel phantom, which is constructed on the basis of Caucasian data.
Ban, Nobuhiko*; Takahashi, Fumiaki; Sato, Kaoru; Endo, Akira; Ono, Koji*; Hasegawa, Takayuki*; Yoshitake, Takayasu*; Katsunuma, Yasushi*; Kai, Michiaki*
Radiation Protection Dosimetry, 147(1-2), p.333 - 337, 2011/09
Times Cited Count:29 Percentile:87.46(Environmental Sciences)A web-system of WAZA-ARI is being developed to assess radiation dose to a patient in a Computed Tomography (CT) examination. The databases of organ doses for WAZA-ARI were derived by the Japanese adult Male phantom (JM phantom) combined with the Particle and Heavy Ion Transport code System, PHITS. In the Monte Carlo simulation, the phantoms were irradiated with a 5 mm-thick fan-shaped photon beam, which was moved every 5 mm along the body axis from the upper leg to the top of head. The attenuation by the beam-shaping filter (bow-tie filter) was also taken into account here. The MIRD-type phantom was also applied to the calculations. The MIRD phantom sometimes showed step changes for organ doses, while smoother curves were obtained for JM phantom. The dose data by JM phantom were incorporated into the WAZA-ARI system, which has been implemented on a Linux server. With regard to the system implementation, the system has achieved a high degree of flexibility without commercial software.
Ban, Nobuhiko*; Takahashi, Fumiaki; Ono, Koji*; Hasegawa, Takayuki*; Yoshitake, Takayasu*; Katsunuma, Yasushi*; Sato, Kaoru; Endo, Akira; Kai, Michiaki*
Radiation Protection Dosimetry, 146(1-3), p.244 - 247, 2011/07
Times Cited Count:22 Percentile:81.45(Environmental Sciences)We are developing a web-based system, WAZA-ARI, for the dose calculation of patients undergoing X-ray CT examinations. Tissue doses were calculated in a Japanese adult male phantom (JM phantom) using a Monte Carlo code, PHITS, and the normalized dose coefficient data are stored as XML files. The system is implemented in Java on a Linux server running Apache Tomcat, which is accessed via a web browser over a network. Users are requested to choose scanning options and to input parameters in the data entry screen. The corresponding dose data are called upon input, and they are summed over the scan range specified by the user to estimate unit tissue doses. Tissue doses are computed based on the radiographic exposure (mAs), the beam pitch and air kerma at the beam center on the axis of rotation. Users can also use their own air kerma, CTDI vol and DLP values for the dose computation instead of the default setting. Although the dose coefficients are prepared for only limited CT scanner models currently, our system has achieved high usability and easy maintenance without commercial software. Possibility of further expansion for the practical application is also discussed.
Takahashi, Fumiaki; Sato, Kaoru; Endo, Akira; Ono, Koji*; Yoshitake, Takayasu*; Hasegawa, Takayuki*; Katsunuma, Yasushi*; Ban, Nobuhiko*; Kai, Michiaki*
Radiation Protection Dosimetry, 146(1-3), p.241 - 243, 2011/07
Times Cited Count:23 Percentile:82.62(Environmental Sciences)A web-system of WAZA-ARI is being developed to assess radiation dose to a patient in a Computed Tomography (CT) examination. WAZA-ARI utilizes a set of organ and tissue doses in a database for the dose assessment, according to the given resources with a consideration of the examination condition. The organ and tissue doses in the database have been derived with the Particle and Heavy Ion Transport code System, PHITS. Modeling of the patient was a significant issue in the radiation transport calculation. JM phantom, whose height (171 cm) and weight (65 kg) are near to those averaged over Japanese male adults, was incorporated to PHITS as a human model. Since JM phantom consisted of about 1 mm
size voxel, the shapes could be realistically reproduced even for small organs such as thyroid, adrenals. Masses of most organs could be also adjusted to the averaged values of Japanese male adults. In addition, our calculations introduced a new phantom without arms based upon JM phantom, because the patient usually puts arms toward the head direction in a torso examination. Some of organ doses calculated by JM phantom were compared with results, which were derived with a MIRD-type phantom. Differences could be seen in some organ doses between the phantoms, if photon attenuations in a shaping (Bow-tie) filter were taken into account to a source model in PHITS.
Takahashi, Fumiaki; Endo, Akira; Sato, Kaoru; Hasegawa, Takayuki*; Katsunuma, Yasushi*; Ono, Koji*; Yoshitake, Takayasu*; Ban, Nobuhiko*; Kai, Michiaki*
Progress in Nuclear Science and Technology (Internet), 1, p.517 - 520, 2011/02
Several dose assessment system were developed to avoid unnecessary exposure for a patient in a Computed Tomography (CT) examination. Most of these systems contain datasets of organ doses, which had been calculated with mathematical phantoms. The numerical analyses for radiation dosimetry and CT machines have progressed in recent years. Thus, a project is being carried out to develop a new dosimetry system, named WAZA-ARI. The basic data of organ doses are calculated with a male voxel phantom (JM phantom), which defines configurations of the human body more precisely than the mathematical model. The radiation transports in CT examination can be simulated with the Particle and Heavy Ion Transport code System, PHITS. A source model can be set up for emissions of photons from the X-ray tube with a subroutine, including the helical scanning. Thus, the WAZA-ARI system can assess radiation dose based upon the organ doses, which are calculated with the appropriate source and human models.
Terunuma, Akihiro; Naito, Akira; Nemoto, Koichi; Usami, Jun; Tomii, Hiroyuki; Shiraishi, Kunio; Ito, Shinichi
JAEA-Review 2010-038, 96 Pages, 2010/09
Japan Atomic Energy Agency (JAEA) has midterm plan for decommissioning the facilities being finished their role and the facilities that became unnecessary by shifting their functions to other facilities. In the first midterm plan (from the latter half of fiscal year 2005 to fiscal year 2009), decommissioning of five facilities (Ceramic Research Facility, Plutonium Research Facility No.2, Metallurgy Research Facility, Isotope Separation Research Facility and Reprocessing Test Facility) had been carried out in order to release controlled area and dismantle the facilities in Nuclear Science Research Institute (NSRI), JAEA. The decommissioning activity for each facility had been reported to the regulatory body and municipalities. On this report, we summarize the each activity for five facilities by reviewing the reports to the regulatory body and municipalities. We also added the knowledge obtained through the activity.
Kanamori, Masashi; Shirakawa, Yusuke; Yamashita, Toshiyuki; Okuno, Hiroshi; Terunuma, Hiroshi; Ikeda, Takeshi; Sato, Sohei; Terakado, Naoya; Nagakura, Tomohiro; Fukumoto, Masahiro; et al.
JAEA-Review 2010-037, 60 Pages, 2010/09
When a nuclear emergency occurs in Japan, the Japan Atomic Energy Agency (JAEA) provides technical support to the National government, local governments, police, fire station and license holder etc. They are designated public organizations conforming to the basic law on emergency preparedness and the basic plan for disaster countermeasures. The Nuclear Emergency Assistance & Training Center (NEAT) of JAEA provides a comprehensive range of technical support activities to an off-site center in case of a nuclear emergency. Specifically, NEAT gives technical advice and information, provides for the dispatch of specialist as required, supplies emergency equipments and materials to the national government and municipal office. NEAT provide various lectures and training course concerning nuclear disaster prevention for those personnel taking an active part in emergency response organizations at normal time. And NEAT researches on nuclear disaster prevention and also cooperate with international organizations. This annual report summarized the activities of JAEA/NEAT in the fiscal year 2009.
Kanamori, Masashi; Hashimoto, Kazuichiro; Terunuma, Hiroshi; Ikeda, Takeshi; Omura, Akiko; Terakado, Naoya; Nagakura, Tomohiro; Fukumoto, Masahiro; Watanabe, Fumitaka; Yamamoto, Kazuya; et al.
JAEA-Review 2009-023, 61 Pages, 2009/09
When a nuclear emergency occurs in Japan, the Japan Atomic Energy Agency (JAEA) provides technical support to the National government, local governments, police, fire station and license holder etc. They are Designated Public Organizations conforming to the Basic Law on Emergency Preparedness and the Basic Plan for Disaster Countermeasures. The Nuclear Emergency Assistance and Training Center (NEAT) of JAEA provides a comprehensive range of technical support activities to an Off-Site Center in case of a nuclear emergency. Specifically, NEAT gives technical advice and information, provides for the dispatch of specialist as required, supplies emergency equipments and materials to the Joint Council of Nuclear Disaster Countermeasures, which meets at the Off-Site Center. NEAT provide various lectures and training course concerning nuclear disaster prevention for those personnel taking an active part in emergency response organizations at normal time. And NEAT researches on nuclear disaster prevention and also cooperate with international organizations. This annual report summarized the activities of JAEA/NEAT in the fiscal year 2008.
Isaka, Koji; Terunuma, Noriaki; Ouchi, Satoshi; Oki, Keiichi; Suwa, Masayuki
Nihon Hozen Gakkai Dai-6-Kai Gakujutsu Koenkai Yoshishu, p.279 - 282, 2009/08
As the modified JRR-3 has been operated for 18 years, it is necessary to be maintained for keeping the safe and stable operation. The review of maintenance activity is constantly performed for the step-by-step update of facilities and the improvement of the maintenance method and so on. Our investigation of the maintenance activity about the instrumentation and control device of modified JRR-3 is presented.
Suwa, Masayuki; Isaka, Koji; Ouchi, Satoshi; Terunuma, Noriaki
UTNL-R-0471, p.12_1_1 - 12_1_8, 2009/03
no abstracts in English
Tanimura, Yoshihiko; Sato, Tatsuhiko; Kumada, Hiroaki; Terunuma, Toshiyuki*; Sakae, Takeji*; Harano, Hideki*; Matsumoto, Tetsuro*; Suzuki, Toshikazu*; Matsufuji, Naruhiro*
Hoshasen, 34(2), p.135 - 139, 2008/04
Recently the traceability system (JCSS) of neutron standard based on the Japanese law "Measurement Act" has been instituted. In addition, importance of the neutron dose evaluation has been increasing in not only the neutron capture medical treatment but also the proton or heavy particle therapy. Against such a background, a symposium "Neutron dosimetry in neutron fields; From detection techniques to medical applications" was held on March 29, 2008 and recent topics on the measuring instruments and their calibration, the traceability system, the simulation technique and the medical applications were introduced. This article summarizes the key points in the discussion at the symposium.
Kurosaki, Yukio*; Yamachi, Hiroshi*; Katsunuma, Yoshio*; Nakata, Masao*; Kuwahara, Hideki*; Yamada, Fumitaka*; Matsushita, Kiyoshi*; Sato, Toshinori*
JAEA-Research 2008-048, 274 Pages, 2008/03
A junction space between a super deep shaft and horizontal drifts forms a 3-dimensional geo-structure, which would take a complicated mechanical behavior during a junction excavation. However, a quantitative design method for a deep junction has not yet established. In order to examine a collapse mechanism of super deep shaft junction, we have conducted literature surveys and interview studies concerned with a collapses. Considering the results of investigations with reviews of intellectuals, the collapse mechanism depends on both a construction procedure of shaft junction and a geological condition. On the other hand, where a deep junction intersects faults and/or fractures with a large angle, a collapse called taka-nuke may occur and a numerical studies that can simulate a practical rock mass behavior around a shaft junction should be carry out. We demonstrate finite difference method is most adequate for these simulations with intellectual review.
Hatae, Takaki; Nakatsuka, Masahiro*; Yoshida, Hidetsugu*; Ebisawa, Katsuyuki*; Kusama, Yoshinori; Sato, Kazuyoshi; Katsunuma, Atsushi*; Kubomura, Hiroyuki*; Shinobu, Katsuya*
Fusion Science and Technology, 51(2T), p.58 - 61, 2007/02
Times Cited Count:6 Percentile:41.32(Nuclear Science & Technology)no abstracts in English
W/
Re generatorsMatsuoka, Hiromitsu; Hashimoto, Kazuyuki; Hishinuma, Yukio*; Ishikawa, Koji*; Terunuma, Hitoshi*; Tatenuma, Katsuyoshi*; Uchida, Shoji*
Journal of Nuclear and Radiochemical Sciences, 6(3), p.189 - 191, 2005/12
Applicability of Mo adsorbent PZC(Poly Zirconium Compound) for
W/
Re generator was investigated. Long term stability of adsorption of
W to the PZC column, elution of
Re from PZC column, desorption of
from PZC column, and labeling of Hydroxyethylidene Diphosphonic Acid(HEDP) and Mercaptoacetyltriglycine(MAG3) with
Re eluted from PZC column were tested. The PZC generator gave reproducible
Re elution yields with low
W parent breakthrough for a long period of time(about 5 months), that is the
W/
Re generator using PZC has a potential for practical use.