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JAEA Reports

Development of MIG2DF Version 2

Takai, Shizuka; Kimura, Hideo*; Uchikoshi, Emiko*; Munakata, Masahiro; Takeda, Seiji

JAEA-Data/Code 2020-007, 174 Pages, 2020/09

JAEA-Data-Code-2020-007.pdf:4.23MB

The MIG2DF computer code is a computer program that simulates groundwater flow and radionuclide transport in porous media for the safety assessment of radioactive waste disposal. The original version of MIG2DF was released in 1992. The original code employs a two-dimensional (vertical or horizontal cross-section, or an axisymmetric configuration) finite-element method to approximate the governing equations for density-dependent saturated-unsaturated groundwater flow and radionuclide transport. Meanwhile, for geological disposal of radioactive wastes, landscape evolution such as uplift and erosion needs to be assessed as a long-term geological and climate events, considering site conditions. In coastal areas, the impact to groundwater flow by change of salinity distribution to sea level change also needs to be considered. To deal with these events in the assessment, we have revised the original version of MIG2DF and developed the external program which enables MIG2DF to consider unsteady landscape evolution. In these developments, this report describes an upgrade of MIG2DF (Version 2) and presents the configuration, equations, methods, and verification. This reports also give the explanation external programs of MIG2DF: PASS-TRAC (the particle tracking code), PASS-PRE (the code for dataset preparation), and PASS-POST (the post-processing visualization system).

Journal Articles

Application of photoluminescence microspectroscopy; A Study on transfer of uranyl and europium ions on dry silica gel plate

Kusaka, Ryoji; Watanabe, Masayuki

Journal of Nuclear Science and Technology, 57(9), p.1046 - 1050, 2020/09

 Times Cited Count:0 Percentile:100(Nuclear Science & Technology)

Journal Articles

Generation of nuclear data using Gaussian process regression

Iwamoto, Hiroki

Journal of Nuclear Science and Technology, 57(8), p.932 - 938, 2020/08

 Times Cited Count:0 Percentile:100(Nuclear Science & Technology)

We present a new approach to generate nuclear data from experimental cross section data by Gaussian process regression. This paper focuses on generating proton-induced nuclide production cross sections for nickel target. Our results provide reasonable fitting curves together with their uncertainties and suggest that this approach appears to be effective in generating or evaluating the nuclear data. Besides, our results suggest that our approach could be available for experimental design in terms of reducing the generated nuclear data uncertainty.

JAEA Reports

Background radiation monitoring using manned helicopter for application of technique of nuclear emergency response in the fiscal year 2018 (Contract research)

Futemma, Akira; Sanada, Yukihisa; Komiya, Tomokazu; Iwai, Takeyuki*; Seguchi, Eisaku*; Matsunaga, Yuki*; Kawabata, Tomoki*; Haginoya, Masashi*; Hiraga, Shogo*; Sato, Kazuhiko*; et al.

JAEA-Technology 2019-017, 95 Pages, 2019/11

JAEA-Technology-2019-017.pdf:12.09MB

By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the Great East Japan Earthquake and the following tsunami on March 11, 2011, a large amount of radioactive material was released from the FDNPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter was conducted around FDNPS. We have carried out the background radiation monitoring around the nuclear power stations of the whole country to apply the airborne radiation monitoring technique that has been cultivated in the aerial monitoring around FDNPS against nuclear emergency response. The results of monitoring around Shimane and Hamaoka Nuclear Power Stations in the fiscal 2018 were summarized in this report. In addition, technical issues were described.

Journal Articles

Sensitivity of charged particle activation analysis for long-lived radioactive nuclide determination

Oshima, Masumi*; Yamaguchi, Yurie*; Asai, Masato; Tsukada, Kazuaki; Goto, Jun*; Bamba, Shigeru*; Bi, C.*; Morimoto, Takao*

Journal of Nuclear Science and Technology, 56(9-10), p.866 - 872, 2019/09

 Times Cited Count:1 Percentile:56.06(Nuclear Science & Technology)

Sensitivity of charged particle activation analysis with 8 MeV proton beam was studied for determination of 35 long-lived radioactive nuclides. Reaction cross sections for those nuclides were estimated with ALICE-91 code and isomer yield ratios were estimated from those of neighboring isotopes by taking into account their spins and parities. It was found that the proposed charged particle activation analysis should show high sensitivity for the determination of several hardly measurable nuclides with long half-lives such as $$^{135}$$Cs, $$^{244}$$Pu, $$^{129}$$I, $$^{126}$$Sn, $$^{93}$$Mo, $$^{107}$$Pd, $$^{236}$$U, $$^{248}$$Cm, and $$^{237}$$Np.

Journal Articles

Student and Young researcher's view of research on health physics and environment science

Miwa, Kazuji; Terasaka, Yuta; Ochi, Kotaro; Futemma, Akira; Sasaki, Miyuki; Hirouchi, Jun

Nippon Genshiryoku Gakkai-Shi, 61(9), p.687 - 691, 2019/09

This report summarizes the contents of the session of the Health Physics and Environment Science Division, which was held in Atomic Energy Society of Japan 2019 Spring Meeting. In this session, six students and young researchers who engaged in the field of nuclear energy and radiation gave a lecture about health physics and environmental science research through their expertise. After the all presentations end, we took discussion time about the issues and future development in this field with all attendees. In this report, we summarized each lecture outline and discussion contents.

Journal Articles

Study on coordination structure of Re adsorbed on Mg-Al layered double hydroxide using X-ray absorption fine structure

Tanaka, Kazuya; Kozai, Naofumi; Onuki, Toshihiko; Grambow, B.

Journal of Porous Materials, 26(2), p.505 - 511, 2019/04

 Times Cited Count:4 Percentile:35.35(Chemistry, Applied)

In this study, we utilized X-ray absorption fine structure spectroscopy to clarify the coordination structure of Re in Mg-Al LDH as a surrogate of Tc. Adsorption experiments of ReO$$_{4}$$$$^{-}$$ on calcined and uncalcined Mg-Al LDHs were conducted in aqueous solutions with different concentrations of NaCl, NaNO$$_{3}$$, and Na$$_{2}$$SO$$_{4}$$. Calcined Mg-Al LDH showed much higher adsorption than uncalcined one. The adsorption of ReO$$_{4}$$$$^{-}$$ was reversible, and decreased with increasing concentration of competing anions like Cl$$^{-}$$, NO$$_{3}$$$$^{-}$$, or SO$$_{4}$$$$^{2-}$$. Analysis of Re L$$_{III}$$-edge extended X-ray absorption fine structure indicated that ReO$$_{4}$$$$^{-}$$ was adsorbed as an outer-sphere complex on Mg-Al LDH. The observed Re adsorption-desorption behavior, which was sensitive to the presence of competing anions, was consistent with the formation of outer sphere-complex.

Journal Articles

Evaluation of a surface collection efficiency and a stability of flow rate for the commercially available filters used for ambient radioactive aerosols

Tamakuma, Yuki*; Yamada, Ryohei; Iwaoka, Kazuki*; Hosoda, Masahiro*; Tokonami, Shinji*

Hoken Butsuri (Internet), 54(1), p.5 - 12, 2019/03

Airborne radioactivity measurements are necessary to know the contamination level and internal doses for residents after a nuclear accident. In addition, measurements of radon progenies in air, which are the risk factor of lung cancer, are also important to evaluate lung dose. In these measurements, a filter sampling is used to collect radioactive aerosols. However, it is well known that results of the measurement using a filter are strongly dependent on characteristics of the used filter. Selection of a suitable filter is important to achieve the high-resolution and long-term measurement. "Surface collection efficiency (SCE)" and "stability of air flow rate" were examined for six types of filter that are commercially available in Japan. In Japan, cellulose-glass fiber filter paper (HE-40T) is used for an environmental monitoring in Japan. In this study, it was found that the SCE of HE-40T was lower than that of mixed cellulose ester type membrane filter by Merck Millipore (DAWP02500). Attenuation ratio of flow rate for DAWP02500 was evaluated to be 2.9% which was lowest in six filters. The results suggest that the DAWP02500 is the most suitable for collecting radioactive aerosols for a long term.

JAEA Reports

Background radiation monitoring using manned helicopter for establishment of technique of nuclear emergency response in the fiscal year 2017 (Contract research)

Futemma, Akira; Sanada, Yukihisa; Iwai, Takeyuki*; Seguchi, Eisaku; Matsunaga, Yuki*; Kawabata, Tomoki; Toyoda, Masayuki*; Tobita, Shinichiro*; Hiraga, Shogo*; Sato, Kazuhiko*; et al.

JAEA-Technology 2018-016, 98 Pages, 2019/02

JAEA-Technology-2018-016.pdf:18.64MB

By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the Great East Japan Earthquake and the following tsunami on March 11, 2011, a large amount of radioactive material was released from the NPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter was conducted around FDNPS. We have carried out the background monitoring around the nuclear power stations of the whole country to apply the airborne radiation monitoring technique that has been cultivated in Fukushima against nuclear emergency response. The results of monitoring around Tomari, Kashiwazaki-Kariwa and Genkai Nuclear Power Station in the fiscal 2017 were summarized in this report. In addition, technical issues were described.

Journal Articles

Investigation of hydrogen gas generation by radiolysis for cement-solidified products of used adsorbents for water decontamination

Sato, Junya; Kikuchi, Hiroshi*; Kato, Jun; Sakakibara, Tetsuro; Matsushima, Ryotatsu; Sato, Fuminori; Kojima, Junji; Nakazawa, Osamu

QST-M-8; QST Takasaki Annual Report 2016, P. 62, 2018/03

no abstracts in English

JAEA Reports

Background radiation monitoring using manned helicopter for establishment of technique of nuclear emergency response in the fiscal year 2016 (Contract research)

Sanada, Yukihisa; Mori, Airi; Iwai, Takeyuki; Seguchi, Eisaku; Matsunaga, Yuki*; Kawabata, Tomoki; Toyoda, Masayuki*; Tobita, Shinichiro*; Hiraga, Shogo; Sato, Yoshiharu; et al.

JAEA-Technology 2017-035, 69 Pages, 2018/02

JAEA-Technology-2017-035.pdf:32.92MB

By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the East Japan earthquake and the following tsunami occurred on March 11, 2011, a large amount of radioactive materials was released from the NPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter was conducted around FDNPS. We carried out the background monitoring around the nuclear power stations of the whole country to apply a technique of the airborne radiation monitoring that is cultivated in Fukushima as a technology of nuclear emergency response. This result of the aerial radiation monitoring using the manned helicopter around Ooi, Takahama and Ikata Nuclear Power Station and in the fiscal 2016 were summarized in the report. In addition, technical issues were described.

Journal Articles

Release and transport behaviors of non-gamma-emitting fission products and actinides in steam and hydrogen atmospheres

Miwa, Shuhei; Ducros, G.*; Hanus, E.*; Bottomley, P. D. W.*; Van Winckel, S.*; Osaka, Masahiko

Nuclear Engineering and Design, 326, p.143 - 149, 2018/01

 Times Cited Count:0 Percentile:100(Nuclear Science & Technology)

The release and transport behaviors of 13 non-gamma-emitting fission products (FPs) and actinides in steam and hydrogen atmospheres were investigated based on the chemical analysis of their deposits on the components of VERCORS test loops. The new findings were obtained; strontium release was significantly enhanced in hydrogen atmosphere and a part of released strontium was transported towards the lower temperature region, uranium release was enhanced in steam atmosphere but most of released uranium deposited at high temperature region.

Journal Articles

Preface of SI; RNs in the environments

Tanaka, Kazuya; Kaplan, D. I.*; Onuki, Toshihiko

Applied Geochemistry, 85(Part B), p.119 - 120, 2017/10

 Times Cited Count:0 Percentile:100(Geochemistry & Geophysics)

We have prepared a special issue for Applied Geochemistry entitled "Transformation and Fate of Natural and Anthropogenic Radionuclides in the Environments". Here, we present 13 peer-reviewed articles on the general theme of natural and anthropogenic radionuclides in different environments. At the same time, these articles cover various topics of field research on the distribution of radionuclides, as well as laboratory experiments on adsorption and redox chemistry of these. The articles have been written by the attendees of the session at the Goldschmidt 2016 held in Yokohama, Japan, and by other authors who submitted their manuscripts to Applied Geochemistry focusing on the theme of the special issue.

Journal Articles

Nuclide partitioning and transmutation technology; Transmutation using fast reactor

Yanagisawa, Tsutomu*; Usami, Shin; Maeda, Seiichiro

Genshiryoku Nenkan 2018, p.90 - 95, 2017/10

no abstracts in English

Journal Articles

Present state of partitioning and transmutation of long-lived nuclides, 1; Significance of partitioning and transmutation and partitioning and transmutation systems

Minato, Kazuo; Tsujimoto, Kazufumi; Tanabe, Hiromi*; Fujimura, Koji*

Nippon Genshiryoku Gakkai-Shi, 59(8), p.475 - 479, 2017/08

no abstracts in English

Journal Articles

Preparation of solid phase extraction cartridges for trace analysis of radionuclides

Asai, Shiho; Saito, Kyoichi*

Biomedical Research on Trace Elements, 28(1), p.1 - 10, 2017/04

Radionuclides are commonly determined with radiometry and mass spectrometry. For $$gamma$$-emitting nuclides, the activities can be measured without chemical separation due to the strong penetration ability. In contrast, the measurements of alpha and beta-emitting nuclides are generally associated with tedious and time-consuming chemical separation procedures to remove concomitants. Thus, an adsorbent that achieves rapid separation is desirable to reduce separation time and workload. Our research team has developed compact cartridge-type solid phase extraction materials which enable to facilitate separation procedures. In this review, basic separation performances of the developed cartridges were overviewed along with two application examples to radionuclide-containing samples.

JAEA Reports

Technological study about a disposal measures of low-level radioactive waste including uranium and long-half-life radionuclides

Sugaya, Toshikatsu; Nakatani, Takayoshi; Sasaki, Toshihisa*; Nakamura, Yasuo*; Sakai, Akihiro; Sakamoto, Yoshiaki

JAEA-Technology 2016-036, 126 Pages, 2017/02

JAEA-Technology-2016-036.pdf:7.28MB

At the Radioactive Waste Management and Disposal Project Department Sector of Decommissioning and Radioactive Waste Management, we performed the technological study about the disposal measures of the low-level radioactive waste targeted for uranium-bearing waste and intermediate depth disposal-based waste occurring from the process of the nuclear fuel cycle.

JAEA Reports

Evaluation of mass transport property using natural Uranium-series and Thorium-series nuclides in the Toki Granite

Hama, Katsuhiro

JAEA-Data/Code 2016-006, 23 Pages, 2016/07

JAEA-Data-Code-2016-006.pdf:1.6MB

The Mizunami Underground Research Laboratory project is being pursued by the Japan Atomic Energy Agency to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host crystalline rock at Mizunami City in Gifu Prefecture, central Japan. The project proceeds in three overlapping phases, Surface-based investigation Phase, Construction Phase and Operation Phase. The MIU Project has been ongoing the Phase III. As a part of the Phase III investigation, evaluation of mass transport property using natural Uranium-series and Thorium-series nuclides has been carried out. In this report, the compilation of existing data and preliminary evaluation was carried out.

Journal Articles

Noble gas monitoring at the Takasaki radionuclide station of JAEA; Certification by the Comprehensive Nuclear-Test-Ban Treaty (CTBT) Organization

Yamamoto, Yoichi

Isotope News, (736), p.31 - 33, 2015/08

The Takasaki radionuclide (RN) station for the Comprehensive Nuclear-Test-Ban Treaty (CTBT) has been in operation for monitoring of radioactive noble gases (radioxenon) by the Japan Atomic Energy Agency (JAEA) since 2007, first as a test run prior to receiving the certification. The noble gas system in the station was certified by the CTBT Organization (CTBTO) on December 19, 2014. Monitoring of radioxenon is expected to have a particularly valuable role in detection of an underground nuclear test. The Takasaki RN station detected radioxenon isotopes simultaneously with radioactive concentration exceeding normal background range in April, 2013. This abnormal event was identified as being associated with the nuclear test declared by North Korea in February, 2013. Since the Takasaki RN station is located at the east end of Asia, it is receiving widespread international attention as the station for radionuclides dispersed by the westerlies.

JAEA Reports

Study on the evaluation method to determine the radioactivity concentration waste generated from post-irradiation examination facilities

Hoshino, Yuzuru; Sakamoto, Yoshiaki; Muroi, Masayuki*; Mukai, Satoru*

JAEA-Technology 2015-015, 96 Pages, 2015/07

JAEA-Technology-2015-015.pdf:20.34MB

In order to dispose of the radioactive waste which generates from post-irradiation examination (PIE) facilities, the common evaluation method of radioactivity in wastes from PIE should be established by the actual data such as radioactivity values and the theoretical calculation. In this study, the radioactivity concentrations of 17 nuclides (H-3, C-14, Co-60, Ni-63, Sr-90, Tc-99, Cs-137, Eu-154, U-234, U-235, U-238, Pu-238, Pu-239, Pu-240, Pu-241, Am-241, Cm-244) in combustible wastes stored in NUCLEAR DEVELOPMENT CORPORATION were measured from 3 samples and the radioactivity was calculated by ORIGEN-2 based on initial contents and operation record of the spent fuel. From the comparison of the obtained data by the radiological measurement with the calculated values, the subject to be solved for establishment of the radioactivity evaluation method for PIE was extracted.

679 (Records 1-20 displayed on this page)