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JAEA Reports

Annual report of Nuclear Science Research Institute, JFY2013 & 2014

Nuclear Science Research Institute

JAEA-Review 2018-036, 216 Pages, 2019/03

JAEA-Review-2018-036.pdf:19.22MB

Nuclear Science Research Institute (NSRI) is composed of Planning and Coordination Office, Fukushima Project Team and six departments, namely Department of Operational Safety Administration, Department of Radiation Protection, Engineering Services Department, Department of Research Reactor and Tandem Accelerator, Department of Fukushima Technology Development and Department of Decommissioning and Waste Management, and each departments manage facilities and develop related technologies to achieve the "Middle-term Plan" successfully and effectively. In order to contribute the future research and development and to promote management business, this annual report summarizes information on the activities of NSRI of JFY 2013 and 2014 as well as the activity on research and development carried out by Nuclear Safety Research Center, Advanced Research Center, Nuclear Science and Engineering Center and Quantum Beam Science Center, and activity of Nuclear Human Resource Development Center, using facilities of NSRI.

Journal Articles

Outline and implementation status of decommissioning plan of JRR-4

Ishikuro, Yasuhiro; Nemoto, Tsutomu; Yamada, Yusuke; Oyama, Koji

Nippon Hozen Gakkai Dai-15-Kai Gakujutsu Koenkai Yoshishu, p.501 - 505, 2018/07

After operating until December 2010, JRR-4 was under periodical self-inspection for the next operation. After that, it suffered from the Great East Japan Earthquake on March 11, 2011. But it recovered almost a year later. However, we determined to decommission JRR-4 in September 2013. After that, we received the approval of the decommissioning plan of JRR-4 on June 7, 2017. And we received the approval of the change of the safety regulations related to it. Subsequently JRR-4 was shifted to decommission phase in December 2017. This report describes the outline of the decommissioning plan of JRR-4 and the implementation status.

Journal Articles

Decommissioning plan of JRR-4

Ishikuro, Yasuhiro; Hirane, Nobuhiko; Kato, Tomoaki

Proceedings of European Research Reactor Conference 2018 (RRFM 2018) (Internet), 7 Pages, 2018/03

Japan Research Reactor No.4 (JRR-4) is a swimming pool type reactor moderated and cooled with light-water. The maximum thermal power of JRR-4 is 3,500kW. Since its initial criticality in January 1965, JRR-4 had been operated about 45 years until in December 2010.Subsequently, the Great East Japan Earthquake occurred on March 11, 2011. Although JRR-4 was no severe damage, we have determined to decommission JRR-4 in consideration of various things. After that, we have submitted the decommissioning plan of JRR-4 to the nuclear regulatory body and have received the approval of it on June 7, 2017. Consequently, JRR-4 has shifted to the phase1 of the decommissioning plan since December.15, 2017 after the approval of its the safety regulation.

Journal Articles

Decommissioning of JRR-4

Ishikuro, Yasuhiro; Wada, Shigeru

UTNL-R-0494, p.6_1 - 6_14, 2017/03

no abstracts in English

JAEA Reports

Characteristics measurement of JRR-4 neutron beam facility; Accuracy estimation of BNCT dose calculation after change of reflector

Horiguchi, Hironori; Nakamura, Takemi; Motohashi, Jun; Kashimura, Takanori; Ichimura, Shigeju; Sasajima, Fumio

JAEA-Technology 2012-003, 38 Pages, 2012/03

JAEA-Technology-2012-003.pdf:2.55MB

Clinical trials of boron neutron capture therapy (BNCT) for malignant brain tumors and head and neck cancers have been performed at the research reactor JRR-4. BNCT is a kind of radiation therapy using a nuclear reaction with thermal neutrons and boron ($$^{10}$$B) elements administered to a patient. The design specifications of all types of reflector elements were changed due to a trouble of a reflector element in JRR-4. In the production of the new reflector elements, they were designed with the influence for the neutron beam facility by the analytical calculation. After the installation of the new reflector elements, the performance of the neutron beam facility was verified by measurement such as a free air experiment and a water phantom experiment. The calculation error used in the treatment planning for BNCT can be estimated by comparing the results of our calculation with the corresponding experimental data.

Journal Articles

Investigation of irradiation conditions for recurrent breast cancer in JRR-4

Horiguchi, Hironori; Nakamura, Takemi; Kumada, Hiroaki*; Yanagie, Hironobu*; Suzuki, Minoru*; Sagawa, Hisashi

Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.234 - 237, 2010/10

Recurrent breast cancer has been considered the application for boron neutron capture therapy using the JRR-4. The investigation of irradiation conditions for the recurrent breast cancer was performed by simulation with the JCDS. We performed the preliminary dosimetry of the model to verify the efficient irradiation conditions such as the neutron energy modes and multiple field technique. From the result, when the 30 Gy-Eq dose as minimum dose was delivered to the cancers, comparable dose distribution was delivered at the healthy tissues by both a one-port irradiation from anterior direction and a two-port irradiation from tangential direction. We revealed that the two-port irradiation was not valid to reduce the healthy tissues dose due to the isotopic scattering of neutrons in the body. We concluded that the optimal irradiation condition was the one-port irradiation with thermal neutron beam mode in terms of less healthy tissues dose and shorter irradiation time.

Journal Articles

Resumption of JRR-4 and characteristics of the neutron beam for BNCT

Nakamura, Takemi; Horiguchi, Hironori; Kishi, Toshiaki; Motohashi, Jun; Sasajima, Fumio; Kumada, Hiroaki*

Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.379 - 382, 2010/10

The clinical trials of BNCT have been conducted using JRR-4. The JRR-4 stopped in January 2008, because the graphite reflector was considerably damaged. For this reason, the specifications of graphite reflectors were renewal. All existing graphite reflectors of JRR-4 were changed by new graphite reflectors. The resumption of JRR-4 was carried out with new graphite reflectors in February 2010. We measured the characteristics of neutron beam at the JRR-4 Neutron Beam Facility. A cylindrical water phantom was put the gap for 1cm from the beam port. TLD and gold wire were inserted within the phantom when the phantom was irradiated. The results of the measured thermal neutron flux and the $$gamma$$ dose in water were compared with MCNP calculations. The calculated results showed the same tendency with the experimental results. These results are proceeding well and will be reported in full paper at July 2010.

Journal Articles

Characteristics measurement of thermal neutron filter developed for improvement of therapeutic dose distribution of JRR-4

Kumada, Hiroaki*; Nakamura, Takemi; Horiguchi, Hironori; Matsumura, Akira*

Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.414 - 417, 2010/10

Journal Articles

Influence of water concentrations to chemical forms of tritium generated in mercury through a nuclear reaction

Manabe, Kentaro; Yokoyama, Sumi

Applied Radiation and Isotopes, 68(3), p.418 - 421, 2010/03

 Times Cited Count:0 Percentile:100(Chemistry, Inorganic & Nuclear)

Influence of water content to chemical forms of tritium generated in mercury was evaluated for assessment of potential internal exposure in the Japan Spallation Neutron Source (JSNS) using a mercury target. In order to simulate the condition of tritium production in the mercury target, mercury samples containing a small amount of metallic lithium as a source of tritium and water were irradiated with a thermal neutron beam. It was found that the ratio of HTO to the sum of HTO and HT increased with the water content in the mercury samples.

Journal Articles

Development of a thermal neutron-sensitive liposome for a novel drug delivery system aiming for radio-chemo-concurrent cancer therapy

Akamatsu, Ken

Radiation Physics and Chemistry, 78(12), p.1179 - 1183, 2009/12

 Times Cited Count:6 Percentile:54.16(Chemistry, Physical)

An ionizing radiation-sensitive liposome has been developed aiming for irradiation site-specific controlled release of an anticancer agent from liposomes accumulated at tumor. As the first step of the study, X-ray-sensitive liposome has been constructed, consisting of an unsaturated phosphatidyl choline (PC), a saturated PC, and cholesterol. The radiation sensitivity was estimated by measuring release rate of a fluorophore, calcein, through the lipid bilayer. As a result, the following characteristics of X-ray-sensitive liposomes were discovered: (1) A PC with bis-allylic hydrogen is an essential component of unsaturated PC, (2) Dilinoleoyl PC (DLOPC) is the most favorable component of unsaturated PC, (3) A lower dose rate makes the liposome more X-ray-sensitive. In this presentation, we will discuss radiation chemical mechanism of the ionizing radiation-sensitive liposome, and their pharmaceutical applications for radiation therapy such as boron neutron capture therapy.

Journal Articles

Investigation of the crack in a reflector element of JRR-4 and future maintenance

Sakata, Mami; Yagi, Masahiro; Horiguchi, Hironori; Hirane, Nobuhiko

Nippon Hozen Gakkai Dai-6-Kai Gakujutsu Koenkai Yoshishu, p.275 - 278, 2009/08

A crack was found on a weld area of one reflector element in JRR-4 on December 28, 2007. The following examinations were carried out, visual examination, dimensional examination, fractography examination and so on. It was concluded that the main cause of the crack is the neutron-induced swelling of graphite in the reflector element. We tested radiographycally the other reflector elements. As the result, we determined that many of them were not in a suitable state to be used because of swelling of graphite. Based on the relation between the irradiation dose and swelling rate, the design of the new reflector elements has been carried out. We decided to test radiographycally all the new reflector elements as the future maintenance.

JAEA Reports

Determination of boron concentration in whole blood by inductively coupled plasma atomic emission spectrometry for boron neutron capture therapy

Horiguchi, Hironori; Yamamoto, Kazuyoshi; Kishi, Toshiaki; Otake, Shinichi*; Kumada, Hiroaki*

JAEA-Research 2009-015, 38 Pages, 2009/07

JAEA-Research-2009-015.pdf:7.61MB

The boron neutron capture therapy (BNCT) has been conducted at JRR-4. There is an increased number of cases due to the expansion of application against head and neck cancer and skin cancer. Therefore, the BNCT requires the establishment of procedure to perform more cases in a day. The determination of boron concentration in blood is important to determine the prescribed dose given to a patient. Currently, prompt $$gamma$$ ray analysis (PGA) is applied to the determination of boron concentration. But the PGA is not applied to more than three times BNCT a day. Therefore, swiftness and precision method by inductively coupled plasma atomic emission spectrometry (ICP-AES) is studied. Using BSH for Boron standard of the ICP-AES, we enabled to analyze accurately without an intricate sample preparation. The measurement precision of the ICP-AES was within 5% by the correction factor based on the PGA. We established the method of swiftness determination of boron concentration in blood for BNCT.

Journal Articles

Conceptual design of experimental equipment for large-diameter NTD-Si

Yagi, Masahiro; Watanabe, Masanori; Oyama, Koji; Yamamoto, Kazuyoshi; Komeda, Masao; Kashima, Yoichi; Yamashita, Kiyonobu

Applied Radiation and Isotopes, 67(7-8), p.1225 - 1229, 2009/07

 Times Cited Count:8 Percentile:45.11(Chemistry, Inorganic & Nuclear)

Journal Articles

Performance measurement of the scintillator with optical fiber detector for boron neutron capture therapy

Komeda, Masao; Kumada, Hiroaki; Ishikawa, Masayori*; Nakamura, Takemi; Yamamoto, Kazuyoshi; Matsumura, Akira*

Applied Radiation and Isotopes, 67(7-8, Suppl.), p.S254 - S257, 2009/07

 Times Cited Count:3 Percentile:72.57(Chemistry, Inorganic & Nuclear)

Journal Articles

Data processing methods for dynamic neutron tomography velocimetry

Kureta, Masatoshi; Kumada, Hiroaki; Kume, Etsuo; Someya, Satoshi*; Okamoto, Koji*

Proceedings of 3rd International Workshop on Process Tomography (IWPT-3) (CD-ROM), 8 Pages, 2009/04

Dynamic neutron tomography velocimetry has been developed in order to obtain the 3-D velocity distribution and flow profile data of liquid metal flow in a heated rod bundle for development of an advanced nuclear reactor. In this paper, data processing methods for the 3-D velocimetry is focused on. The data processing is started from the reading images recorded by the three high-speed video cameras, and is finished to the visualization of velocity of the tracers and the profiles. Basic experiments were carried out using the research reactor JRR-4 and the dynamic neutron tomography system. As the results, it was confirmed that the 3-D velocity distribution and flow profile could be visualized by the new data processing methods.

Journal Articles

Dynamic neutron computer tomography technique for velocity measurement in liquid metal flow; Fundamental PTV experiment

Kureta, Masatoshi; Kumada, Hiroaki*; Kume, Etsuo; Someya, Satoshi*; Okamoto, Koji*

Journal of Physics; Conference Series, 147, p.012087_1 - 012087_14, 2009/03

The aim of this development is to visualize and measure the velocity distribution in liquid metal flow using the neutron beam with the high-speed imaging technique, computer tomography (CT) technique and particle tracking velocimetry (PTV). Final research purpose is to obtain the velocity distribution and flow profile data of liquid metal flow in a heated rod bundle for development of the FBR core. In this paper, visualization and measurement method using the JRR-4, spring model PTV method for this technique and results of the fundamental PTV experiment were reported. The fundamental experiment was conducted. As the result, cadmium tracers buried in the aluminum column with the speed of 1.5 revolving per second could be visualized as the 3D movie under 125Hz and 250Hz sampling conditions, the profile of the tracer could be traced, and fundamental velocity distribution measurement method could be conformed.

Journal Articles

Dynamic neutron computer tomography technique for velocity measurement in liquid metal flow; Fundamental PTV experiment

Kureta, Masatoshi; Kumada, Hiroaki; Kume, Etsuo; Someya, Satoshi*; Okamoto, Koji*

Proceedings of 6th International Symposium on Measurement Techniques for Multiphase Flows (ISMTMF 2008) (USB Flash Drive), 14 Pages, 2008/12

The aim of this development is to visualize and measure the velocity distribution in liquid metal flow using the neutron beam with the high-speed imaging technique, computer tomography (CT) technique and particle tracking velocimetry (PTV). Final research purpose is to obtain the velocity distribution and flow profile data of liquid metal flow in a heated rod bundle for development of the FBR core. In this paper, visualization and measurement method using the JRR-4, spring model PTV method for this technique and results of the fundamental PTV experiment were reported. The fundamental experiment was conducted. As the result, cadmium tracers buried in the aluminum column with the speed of 1.5 revolving per second could be visualized as the 3D movie under 125 Hz and 250 Hz sampling conditions, the profile of the tracer could be traced, and fundamental velocity distribution measurement method could be conformed.

Journal Articles

Performance measurement of the SOF detector for boron neutron capture therapy

Komeda, Masao; Kumada, Hiroaki; Ishikawa, Masayori*; Nakamura, Takemi; Yamamoto, Kazuyoshi; Matsumura, Akira*

Proceedings of 13th International Congress on Neutron Capture Therapy (ICNCT-13) (CD-ROM), 3 Pages, 2008/11

In this report, deterioration of a SOF detector that can measure thermal neutron in real time was investigated in irradiation experiments. Sensitivity of a SOF detector decreased by 2.0% after an irradiation of about 4 hours. Then thermal neutron fluence was approximately 2.0$$times$$10$$^{13}$$ (n/cm$$^{2}$$). And after the SOF detector was used for about 2 months, sensitivity decreased to 42%. Then thermal neutron fluence was approximately 6.4$$times$$10$$^{14}$$ (n/cm$$^{2}$$). Supposing that thermal neutron fluence is 2$$times$$10$$^{12}$$ (n/cm$$^{2}$$) on the surface of a patient at a BNCT, sensitivity of a SOF detector is considered to be decreased by approximately 0.3% at a BNCT. Therefore it is considered that countermeasure against deterioration is necessary for using a SOF detector at BNCT in the future.

JAEA Reports

Irradiation growth of graphite reflector installed in JRR-4

Yagi, Masahiro; Horiguchi, Hironori; Yokoo, Kenji; Oyama, Koji; Kusunoki, Tsuyoshi

JAEA-Technology 2008-072, 79 Pages, 2008/09

JAEA-Technology-2008-072.pdf:43.31MB

A crack had been found on the weld of one reflector element in JRR-4. A survey revealed that the cause for the crack was the expansion of graphite reflector in the reflector element. It appeared that the expansion of graphite reflector was caused by fast neutron irradiation at low temperature. The survey confirmed radiographically that graphite reflectors in the other reflector elements without the crack expanded similarly by the irradiation growth. Irradiated graphite reflectors were carefully observed and were precisely measured the three dimensions after dismantling the irradiated reflector elements in order to understand quantitatively the irradiation growth behavior of IG-110 graphite under the JRR-4 operation condition. As the results, it was confirmed that growth of graphite reflectors increased with increasing of fast neutron fluence. The maximum irradiation growth per fast neutron fluence was 7.13$$times$$10$$^{-25}$$%m$$^{2}$$/n, the minimum was 4.21$$times$$10$$^{-25}$$%m$$^{2}$$/n, the average was 5.71$$times$$10$$^{-25}$$%m$$^{2}$$/n in the range of fast neutron fluence below 2.5$$times$$10$$^{24}$$n/m$$^{2}$$.

JAEA Reports

Investigation of the crack in a reflector element of JRR-4

The ad hoc Working Group of Investigating into the Crack on a Reflector Element of JRR-4

JAEA-Technology 2008-070, 121 Pages, 2008/09

JAEA-Technology-2008-070(errata).pdf:0.06MB
JAEA-Technology-2008-070-1.pdf:40.24MB
JAEA-Technology-2008-070-2.pdf:56.57MB

A crack was ascertained on a weld area of one reflector element on December 28, 2007. The Department of Research Reactor and Tandem Accelerator set up an ad hoc working group of experts in the JAEA, and investigated cause of crack on the weld area. The following examinations were carried out; visual examination, dimensional examination, fractography examination and so on. It was concluded that the main cause of the crack is the swelling of graphite in the reflector element. The swelling must be due to neutron irradiation. We carried out a radiografical examination of the other reflector elements. As the result, we determined that many of them were not in a suitable state to be used because of swelling of graphite. The design of the new reflector elements should be carried out, based on the relation between the irradiation dose and swelling rate, which has been obtained in these investigation.

136 (Records 1-20 displayed on this page)