Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 335

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 ...

Save select records

JAEA Reports

Analysis of the radioactivity concentrations in radioactive waste generated from JRR-3, JRR-4 and JRTF facilities, 2

Tobita, Minoru*; Goto, Katsunori*; Omori, Takeshi*; Osone, Osamu*; Haraga, Tomoko; Aono, Ryuji; Konda, Miki; Tsuchida, Daiki; Mitsukai, Akina; Ishimori, Kenichiro

JAEA-Data/Code 2023-011, 32 Pages, 2023/11

JAEA-Data-Code-2023-011.pdf:0.93MB

Radioactive wastes generated from nuclear research facilities in Japan Atomic Energy Agency are planning to be buried in the near surface disposal field as trench and pit. Therefore, it is required to establish the method to evaluate the radioactivity concentrations of radioactive wastes until the beginning of disposal. In order to contribute to the study of radioactivity concentration evaluation methods for radioactive wastes generated from nuclear research facilities, we collected and analyzed concrete samples generated from JRR-3, JRR-4 and JAERI Reprocessing Test Facility. In this report, we summarized the radioactivity concentrations of 23 radionuclides ($$^{3}$$H, $$^{14}$$C, $$^{36}$$Cl, $$^{41}$$Ca, $$^{60}$$Co, $$^{63}$$Ni, $$^{90}$$Sr, $$^{94}$$Nb, $$^{rm 108m}$$Ag, $$^{137}$$Cs, $$^{133}$$Ba, $$^{152}$$Eu, $$^{154}$$Eu, $$^{rm 166m}$$Ho, $$^{234}$$U, $$^{235}$$U, $$^{238}$$U, $$^{238}$$Pu, $$^{239}$$Pu, $$^{240}$$Pu, $$^{241}$$Am, $$^{243}$$Am, $$^{244}$$Cm) which were obtained from radiochemical analysis of the samples in fiscal years 2021-2022.

Journal Articles

Neutron capture cross-section measurement by mass spectrometry for Pb-204 irradiated in JRR-3

Nakamura, Shoji; Shibahara, Yuji*; Kimura, Atsushi; Endo, Shunsuke; Shizuma, Toshiyuki*

Journal of Nuclear Science and Technology, 60(9), p.1133 - 1142, 2023/09

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

In recent years, research has been advanced on lead-cooled fast reactors and accelerator drive systems, and it is required to improve the accuracy of the neutron capture cross section of Pb isotopes. Although $$^{204}$$Pb has a small natural abundance, it is of importance because it produces the long-lived radionuclide $$^{205}$$Pb (17.3 million years) by neutron capture reaction. However, it is difficult to measure its cross section by a conventional activation method using a nuclear reactor because the induced radioactivity of $$^{205}$$Pb is weak. Hence, the cross-section measurement was performed by applying mass spectrometry. This presentation gives the details of the experiment and the results obtained in the neutron capture cross-section measurement of $$^{204}$$Pb using mass spectroscopy.

Journal Articles

Neutron science for competiveness of Japan

Oigawa, Hiroyuki

Shiki, 59, P. 1, 2023/06

There are the world's leading neutron science research facilities, J-PARC and JRR-3, in Tokai-mura. In order to convey the value created by these facilities to the public, it is important for users to appeal their achievements.

JAEA Reports

Thermal-hydraulic design calculations for JRR-3 cold neutron source with the new moderator cell

Tokunaga, Sho; Horiguchi, Hironori; Nakamura, Takemi

JAEA-Technology 2023-001, 37 Pages, 2023/05

JAEA-Technology-2023-001.pdf:1.39MB

The cold neutron source (CNS) of the research reactor JRR-3 converts thermal neutrons generated in the reactor into low-energy cold neutrons by moderating them with liquid hydrogen stored in the moderator cell. Cold neutrons generated by the CNS are transported to experimental instruments using neutron conduits, and are used for many studies of physical properties, mainly in life science, polymer science, environmental science, etc. Improvement of cold neutron intensity is essential to maintain competitiveness with the world's research reactors in neutron science, and we are developing a new CNS that incorporates new knowledge. The current moderator cell for the CNS of JRR-3 is a stainless-steel container which is a canteen bottle type, and the cold neutron intensity can be improved by changing the material and shape. Therefore, the basic specifications of the new moderator cell were changed to aluminum alloy which has a smaller neutron absorption cross section, and the shape was optimized using a Monte Carlo code MCNP. Since these changes in specifications will result in changes in heat generation and heat transfer conditions, the CNS of JRR-3 was re-evaluated in terms of self-regulating characteristic, heat transport limits, heat resistance and pressure resistance, etc., to confirm its feasibility in thermal-hydraulic design. This report summarizes the results of the thermal-hydraulic design evaluation of the new moderator cell.

JAEA Reports

Analysis of the radioactivity concentrations in radioactive waste generated from JRR-2, JRR-3 and Hot laboratory

Aono, Ryuji; Mitsukai, Akina; Tsuchida, Daiki; Konda, Miki; Haraga, Tomoko; Ishimori, Kenichiro; Kameo, Yutaka

JAEA-Data/Code 2023-002, 81 Pages, 2023/05

JAEA-Data-Code-2023-002.pdf:3.0MB

Radioactive wastes generated from nuclear research facilities in Japan Atomic Energy Agency are planning to be buried in the near surface disposal field as trench and pit. Therefore, it is required to establish the method to evaluate the radioactivity concentrations of radioactive wastes until the beginning of disposal. In order to contribute to this work, we collected and analyzed the samples generated from JRR-2, JRR-3 and Hot laboratory facilities. In this report, we summarized the radioactivity concentrations of 20 radionuclides ($$^{3}$$H, $$^{14}$$C, $$^{36}$$Cl, $$^{60}$$Co, $$^{63}$$Ni, $$^{90}$$Sr, $$^{94}$$Nb, $$^{99}$$Tc, $$^{rm 108m}$$Ag, $$^{129}$$I, $$^{137}$$Cs, $$^{152}$$Eu, $$^{154}$$Eu, $$^{234}$$U, $$^{238}$$U, $$^{238}$$Pu, $$^{239}$$Pu, $$^{240}$$Pu, $$^{241}$$Am, $$^{244}$$Cm) which were obtained from radiochemical analysis of the samples in fiscal year 2020.

JAEA Reports

Impact assessment for internal overflow in JRR-3

Tokunaga, Sho; Iguchi, Shintaro; Kawamura, Sho; Hirane, Nobuhiko

JAEA-Technology 2022-004, 74 Pages, 2023/02

JAEA-Technology-2022-004.pdf:2.46MB

In JRR-3, in response to the new regulatory standard for research reactors that is enforced December 2013, we submitted the application document of reactor installation license for the JRR-3 on September 2014, and acquired the permission on November 2018. Thereafter, we carried out impact assessment for internal overflow based on the design principles as described in the application document of reactor installation license for the JRR-3. There are two legal requirements for internal overflow. The first is to ensure that the necessary safety functions are not lost due to internal overflow that occur in the facility. The second is to prevent leakage of liquid containing radioactive materials outside the radiation controlled area in the event of an internal overflow. For these requirements, assuming each overflow source, it was confirmed that the necessary safety functions would not be lost and that liquid containing radioactive materials would not leak outside the controlled area. Regarding these assessments, design and construction plans were submitted in installments, and the approvals were obtained sequentially. This report shows the result that is impact assessment for internal overflow in JRR-3.

JAEA Reports

Overhaul of the Primary cooling system heat exchanger in JRR-3

Uno, Yuki; Ouchi, Yasuhiro; Ouchi, Satoshi; Baba, Ryota; Kikuchi, Masanobu; Kawamata, Satoshi

JAEA-Technology 2021-046, 39 Pages, 2023/02

JAEA-Technology-2021-046.pdf:3.76MB

JRR-3 (Japan Research Reactor No.3) is a light water research reactor cooling pool type light water deceleration of low-enriched uranium up to 20MW thermal power. November 1990, begin to operation in modified that we are provided to users as a high neutron flux form reactor facility in various types of irradiation facilities and neutron beam experiment equipment. Currently, JRR-3 has completed the period of facility inspections, which had been extended due to the effects of the Great East Japan Earthquake of March 11, 2011, and has been able to conformity to the New Regulatory Requirements. It has also resumed operation for the first time in about 10 years. FY 2017, overhauled the primary cooling heat exchanger No.1 and No.2 based on a maintenance plan. This is report for take advantage what inspection and maintenance of future about overhaul of the primary cooling system heat exchanger for collect of inspection records and performance.

JAEA Reports

Evaluation of insertion property of control rod of JRR-3 at earthquake by time history response analysis method

Kawamura, Sho; Kikuchi, Masanobu; Hosoya, Toshiaki

JAEA-Technology 2021-041, 103 Pages, 2023/02

JAEA-Technology-2021-041.pdf:8.7MB

In response to new regulatory standard for research and test reactor which is enforced December 2013, JRR-3 got license in November 2018 by formulate new design basis ground motion. After that we evaluated for insertion property of control rod using that new design basis ground motion, and that evaluation results were accepted as approval of the design and construction method by Nuclear Regulation Authority. Now, we re-evaluated to insertion property of control rod about neutron absorber and follower fuel element by time history response analysis method. In this report, it shows that new results have sufficiency of margin compared with the past results that are accepted as approval of the design and construction method.

JAEA Reports

Seismic evaluation of the CRDM and the CRDM guide tube for JRR-3

Kikuchi, Masanobu; Kawamura, Sho; Hosoya, Toshiaki

JAEA-Technology 2021-040, 86 Pages, 2023/02

JAEA-Technology-2021-040.pdf:3.26MB

In JRR-3, in response to new regulatory standard for research and test reactor which is enforced December 2013, we established new design basis ground motion for confirming new regulatory standard and carried out seismic evaluations of the appointments, instruments and structures which are installed in JRR-3 by using that earthquake motion. This report shows that the result of evaluations by fatigue strength evaluation, which is more detailed evaluation approach, about Control Rod Drive Mechanism (CRDM) and the CRDM Guide Tube that have gotten the serious result of seismic safety margin by using time history response analysis method. As a result, it was confirmed that CRDM and the CRDM Guide Tube have sufficient seismic safety margin.

JAEA Reports

Analysis of the radioactivity concentrations in radioactive waste generated from JRR-3, JRR-4 and JRTF facilities

Tobita, Minoru*; Konda, Miki; Omori, Takeshi*; Nabatame, Tsutomu*; Onizawa, Takashi*; Kurosawa, Katsuaki*; Haraga, Tomoko; Aono, Ryuji; Mitsukai, Akina; Tsuchida, Daiki; et al.

JAEA-Data/Code 2022-007, 40 Pages, 2022/11

JAEA-Data-Code-2022-007.pdf:1.99MB

Radioactive wastes generated from nuclear research facilities in Japan Atomic Energy Agency are planning to be buried in the near surface disposal field. Therefore, it is required to establish the method to evaluate the radioactivity concentrations of radioactive wastes until the beginning of disposal. In order to contribute to this work, we collected and analyzed concrete, ash, ceramic and brick samples generated from JRR-3, JRR4 and JRTF facilities. In this report, we summarized the radioactivity concentrations of 24 radionuclides ($$^{3}$$H, $$^{14}$$C, $$^{36}$$Cl, $$^{41}$$Ca, $$^{60}$$Co, $$^{63}$$Ni, $$^{90}$$Sr, $$^{94}$$Nb, $$^{99}$$Tc, $$^{rm 108m}$$Ag, $$^{129}$$I, $$^{137}$$Cs, $$^{133}$$Ba, $$^{152}$$Eu, $$^{154}$$Eu, $$^{rm 166m}$$Ho, $$^{234}$$U, $$^{238}$$U, $$^{238}$$Pu, $$^{239}$$Pu, $$^{240}$$Pu, $$^{241}$$Am, $$^{243}$$Am, $$^{244}$$Cm) which were obtained from radiochemical analysis of the samples in fiscal years 2020-2021.

JAEA Reports

Analysis of the radioactivity concentrations in low-level radioactive waste generated from JPDR, JRR-3 and JRR-4 Facilities

Tsuchida, Daiki; Mitsukai, Akina; Aono, Ryuji; Haraga, Tomoko; Ishimori, Kenichiro; Kameo, Yutaka

JAEA-Data/Code 2022-004, 87 Pages, 2022/07

JAEA-Data-Code-2022-004.pdf:6.73MB

Radioactive wastes generated from nuclear research facilities in Japan Atomic Energy Agency are planning to be buried in the near surface disposal field. Therefore, it is required to establish the method to evaluate the radioactivity concentrations of radioactive wastes until by the beginning of disposal. In order to contribute to this work, we collected and analyzed samples generated from JPDR, JRR-3 and JRR-4. In this report, radioactivity concentrations of 20 radionuclides ($$^{3}$$H, $$^{14}$$C, $$^{36}$$Cl, $$^{60}$$Co, $$^{63}$$Ni, $$^{90}$$Sr, $$^{94}$$Nb, $$^{99}$$Tc, $$^{rm 108m}$$Ag, $$^{129}$$I, $$^{137}$$Cs, $$^{152}$$Eu, $$^{154}$$Eu, $$^{234}$$U, $$^{238}$$U, $$^{238}$$Pu, $$^{239+240}$$Pu, $$^{241}$$Am, $$^{244}$$Cm) were determined based on radiochemical analysis and summarized as basic data for the study of evaluation method of radioactive concentration.

Journal Articles

Resumption of radioisotope production in the Research Reactor JRR-3

Endo, Akira

Isotope News, (781), P. 3, 2022/06

The research reactor JRR-3 at the Nuclear Science Research Institute of Japan Atomic Energy Agency resumed its operation in February 2021 for the first time in 10 years. After commissioning, neutron beam experimental apparatus and irradiation facilities were used from July to November, and the operation in 2021 was completed as planned. During this period, Ir-192 and Au-198 were produced and supplied for therapeutic use, and test irradiation for the production of Mo-99 was performed. This is resumption of radioisotope production using nuclear reactors in Japan, which had stopped after the Great East Japan Earthquake. This article introduces future efforts of radioisotope production for medical applications in JRR-3.

Journal Articles

Journal Articles

To be a global center for neutron utilization; Resumption of operation of JRR-3

Endo, Akira

Hokeikyo Nyusu, (68), P. 1, 2021/10

This article introduces resumption of utilization of the research reactor JRR-3 at the Nuclear Science Research Institute, JAEA. JRR-3 resumed its operation in July 2021 for the first time in 10 years and 7 months, after the confirmation of its conformity to the new regulatory requirements established by the Nuclear Regulatory Commission following the accident at the TEPCO's Fukushima Daiichi Nuclear Power Plant in March 2011. JRR-3 is expected to produce many research results in academic and industrial applications as a research center for neutron science in collaboration with the Materials and Life Science Facility (MFL) of the Japan Proton Accelerator Research Complex (J-PARC).

JAEA Reports

Analysis of the radioactivity concentrations in low-level radioactive waste generated from JRR-3 and JPDR facilities

Tsuchida, Daiki; Haraga, Tomoko; Tobita, Minoru*; Omori, Hiroyuki*; Omori, Takeshi*; Murakami, Hideaki*; Mitsukai, Akina; Aono, Ryuji; Ishimori, Kenichiro; Kameo, Yutaka

JAEA-Data/Code 2020-022, 34 Pages, 2021/03

JAEA-Data-Code-2020-022.pdf:1.74MB

Radioactive wastes generated from nuclear research facilities in Japan Atomic Energy Agency are planning to be buried in the near surface disposal field. Therefore, it is required to establish the method to evaluate the radioactivity concentrations of radioactive wastes until the beginning of disposal. In order to contribute to this work, we collected and analyzed concrete samples generated from JRR-3 and JPDR. In this report, we summarized the radioactivity concentrations of 22 radionuclides($$^{3}$$H, $$^{14}$$C, $$^{36}$$Cl, $$^{41}$$Ca, $$^{60}$$Co, $$^{63}$$Ni, $$^{90}$$Sr, $$^{94}$$Nb, $$^{rm 108m}$$Ag, $$^{133}$$Ba, $$^{137}$$Cs, $$^{152}$$Eu, $$^{154}$$Eu, $$^{rm 166m}$$Ho, $$^{234}$$U, $$^{238}$$U, $$^{238}$$Pu, $$^{239+240}$$Pu, $$^{241}$$Am, $$^{243}$$Am, $$^{244}$$Cm) which were obtained from radiochemical analysis of the samples.

Journal Articles

Expecting big wave of innovation from a small ripple caused by neutrons

Oigawa, Hiroyuki

Hamon, 31(1), P. 1, 2021/02

We have been proceeding with aseismic reinforcing work of the research reactor JRR-3 at the Nuclear Science Research Institute aiming at its restart in February, 2021. All the users of JRR-3 are kindly requested to create innovation with paying attention to safety. For this purpose, we would like to make improvements in safety management, administration system, exchange of researchers, and so on.

Journal Articles

User support and promotion for JRR-3

Matsue, Hideaki

Hamon, 31(1), p.3 - 4, 2021/02

no abstracts in English

Journal Articles

Triple axis spectrometers of JAEA

Osakabe, Toyotaka

Hamon, 31(1), p.14 - 17, 2021/02

no abstracts in English

Journal Articles

SUIREN (polarized neutron reflectometer)

Takeda, Masayasu

Hamon, 31(1), p.18 - 19, 2021/02

no abstracts in English

335 (Records 1-20 displayed on this page)