Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 3190

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

Journal Articles

Interaction of solute manganese and nickel atoms with dislocation loops in iron-based alloys irradiated with 2.8 MeV Fe ions at 400 $$^{circ}$$C

Nguyen, B. V. C.*; Murakami, Kenta*; Chena, L.*; Phongsakorn, P. T.*; Chen, X.*; Hashimoto, Takashi; Hwang, T.*; Furusawa, Akinori; Suzuki, Tatsuya*

Nuclear Materials and Energy (Internet), 39, p.101639_1 - 101639_9, 2024/06

Journal Articles

A Science-based mixed oxide property model for developing advanced oxide nuclear fuels

Kato, Masato; Oki, Takumi; Watanabe, Masashi; Hirooka, Shun; Vauchy, R.; Ozawa, Takayuki; Uwaba, Tomoyuki; Ikusawa, Yoshihisa; Nakamura, Hiroki; Machida, Masahiko

Journal of the American Ceramic Society, 107(5), p.2998 - 3011, 2024/05

 Times Cited Count:0 Percentile:0.01(Materials Science, Ceramics)

Journal Articles

Determination of $$^{90}$$Sr in highly radioactive aqueous samples via conversion to a kinetically stable 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid complex followed by concentration-separation-fractionation based on capillary electrophoresis-liquid scintillation

Ouchi, Kazuki; Haraga, Tomoko; Hirose, Kazuki*; Kurosawa, Yuika*; Sato, Yoshiyuki; Shibukawa, Masami*; Saito, Shingo*

Analytica Chimica Acta, 1298, p.342399_1 - 342399_7, 2024/04

Given that conventional methods of high-dose sample analysis pose substantial exposure risks and generate large amounts of secondary radioactive waste, faster procedures allowing for decreased radiation emission are highly desirable. To address this need, we developed a $$^{90}$$Sr$$^{2+}$$ quantitation technique that is based on liquid scintillation counting-coupled capillary transient isotachophoresis (ctITP) with two-point detection and relies on the rapid concentration, separation, and fractionation of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-complexed $$^{90}$$Sr$$^{2+}$$ in a single run. This method, which allows for the handling of high-dose radioactive specimens at the microliter level and is substantially faster than conventional ion-exchange protocols, was used to selectively quantify $$^{90}$$Sr$$^{2+}$$ in real high-dose waste. The successful concentration-separation in ctITP was ascribed to the inertness of the Sr-DOTA complex to dissociation.

JAEA Reports

Improvement of aerosol time-of-flight mass spectrometer for on-line measurement of tiny particles containing alpha emitters (Contract research); FY2021 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Osaka University*

JAEA-Review 2023-039, 71 Pages, 2024/03

JAEA-Review-2023-039.pdf:4.43MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2021. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station (1F), Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2021, this report summarizes the research results of the "Improvement of aerosol time-of-flight mass spectrometer for on-line measurement of tiny particles containing alpha emitters" conducted in FY2021. The present study aims to improve Aerosol Time-Of-Flight Mass Spectrometer in order to monitor tiny particles containing alpha emitters such as U and Pu generated in removing debris from the reactors of 1F. In FY2021, for improving mass-resolution, we designed the optimized structure of mass spectrometer with much better mass resolution and ion transmittance than commercial ATOFMS by a PC simulation. Further, design of a detection part of ATOFMS fitted to the mass spectrometer was completed.

Journal Articles

Atomic position and the chemical state of an active Sn dopant for Sn-doped $$beta$$-Ga$$_{2}$$O$$_{3}$$(001)

Tsai, Y. H.*; Kobata, Masaaki; Fukuda, Tatsuo; Tanida, Hajime; Kobayashi, Toru; Yamashita, Yoshiyuki*

Applied Physics Letters, 124(11), p.112105_1 - 112105_5, 2024/03

JAEA Reports

Contribution to risk reduction in decommissioning works by the elucidation of basic property of radioactive microparticles (Contract Research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Ibaraki University*

JAEA-Review 2023-021, 112 Pages, 2024/02

JAEA-Review-2023-021.pdf:7.1MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2020. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2018, this report summarizes the research results of the "Contribution to Risk Reduction in Decommissioning Works by the Elucidation of Basic Property of Radioactive Microparticles" conducted from FY2018 to FY2021 (this contract was extended to FY2021). The present study aims to understand the basic properties (size, chemical composition, isotopic composition - including concentration of $$alpha$$-emitters, electrostatic properties, and optical properties, etc.) of fine particles composed of silicate with insoluble properties which contain regions of highly concentrated radioactive cesium (Cs) released to the environment by the accident at the Fukushima Daiichi Nuclear Power Station of TEPCO in 2011 March.

Journal Articles

Processing of JENDL-5 photonuclear sublibrary

Konno, Chikara

JAEA-Conf 2023-001, p.143 - 146, 2024/02

I modified NJOY2016.67 to produce photonuclear ACE files which can be used in MCNP6.2 and PHITS3.27 and produced the ACE file of the JENDL-5 photonuclear sub-library. Simple test calculations with the produced ACE file supported that the produced ACE file had no serious problems.

Journal Articles

A Study on the effects of photogrammetry by the camera angle of view using computer simulation

Nakamura, Keita; Hanari, Toshihide; Matsumoto, Taku; Kawabata, Kuniaki; Yashiro, Hiroshi*

Journal of Robotics and Mechatronics, 36(1), p.115 - 124, 2024/02

Journal Articles

Search for the 6$$alpha$$ condensed state in $$^{24}$$Mg using the $$^{12}$$C+$$^{12}$$C scattering

Fujikawa, Y.*; Kawabata, T.*; Adachi, S.*; Hirose, Kentaro; Makii, Hiroyuki; Nishio, Katsuhisa; Orlandi, R.; Suzaki, Fumi; 13 of others*

Physics Letters B, 848, p.133834_1 - 133834_6, 2024/01

 Times Cited Count:0 Percentile:0.02(Astronomy & Astrophysics)

Journal Articles

Simulated performance evaluation of d-Be compact fast neutron source

Nakayama, Shinsuke

Journal of Nuclear Science and Technology, 60(12), p.1447 - 1453, 2023/12

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

The d+Be neutron source is a candidate for transportable neutron source for on-site nondestructive inspection of infrastructure facilities such as bridges, tunnels and so on. The applicability of the d+Be neutron source to a transportable fast neutron source is explored by Monte Carlo particle transport simulations with PHITS and JENDL-5. The simulation results show that by increasing the shielding thickness by about 1.5 times, it is possible to realize the d+Be neutron source with the comparable performance to another candidate, the 2.5-MeV p+Li neutron source, at lower beam energy.

Journal Articles

Ionic radii in fluorites

Vauchy, R.; Hirooka, Shun; Murakami, Tatsutoshi

Materialia, 32, p.101934_1 - 101934_12, 2023/12

Journal Articles

Ionic radii in halites

Vauchy, R.; Hirooka, Shun; Murakami, Tatsutoshi

Materialia, 32, p.101943_1 - 101943_8, 2023/12

Journal Articles

Nuclear data as foundation of nuclear research and development

Fukahori, Tokio; Nakayama, Shinsuke; Katabuchi, Tatsuya*; Shigyo, Nobuhiro*

Nihon Genshiryoku Gakkai-Shi ATOMO$$Sigma$$, 65(12), p.726 - 727, 2023/12

The Investigative Committee on Nuclear Data investigates and observes global trends in nuclear research and development and conducts comprehensive examinations of Japanese nuclear data activities from a broader perspective, as well as cooperation with domestic and foreign academic institutions in a wide range of fields other than the Atomic Energy Society. We aim to establish a system for communication, information exchange, and interdisciplinary cooperation. In this report, we will report on three of the main activities for the 2021-2022 term: a request list site for nuclear data, human resource development, and roadmap production.

Journal Articles

Impact of the Ce$$4f$$ states in the electronic structure of the intermediate-valence superconductor CeIr$$_3$$

Fujimori, Shinichi; Kawasaki, Ikuto; Takeda, Yukiharu; Yamagami, Hiroshi; Sasabe, Norimasa*; Sato, Yoshiki*; Shimizu, Yusei*; Nakamura, Ai*; Maruya, A.*; Homma, Yoshiya*; et al.

Electronic Structure (Internet), 5(4), p.045009_1 - 045009_7, 2023/11

Journal Articles

Sintering and microstructural behaviors of mechanically blended Nd/Sm-doped MOX

Hirooka, Shun; Horii, Yuta; Sunaoshi, Takeo*; Uno, Hiroki*; Yamada, Tadahisa*; Vauchy, R.; Hayashizaki, Kohei; Nakamichi, Shinya; Murakami, Tatsutoshi; Kato, Masato

Journal of Nuclear Science and Technology, 60(11), p.1313 - 1323, 2023/11

 Times Cited Count:3 Percentile:95.99(Nuclear Science & Technology)

Additive MOX pellets are fabricated by a conventional dry powder metallurgy method. Nd$$_{2}$$O$$_{3}$$ and Sm$$_{2}$$O$$_{3}$$ are chosen as the additive materials to simulate the corresponding soluble fission products dispersed in MOX. Shrinkage curves of the MOX pellets are obtained by dilatometry, which reveal that the sintering temperature is shifted toward a value higher than that of the respective regular MOX. The additives, however, promote grain growth and densification, which can be explained by the effect of oxidized uranium cations covering to a pentavalent state. Ceramography reveals large agglomerates after sintering, and Electron Probe Micro-Analysis confirms that inhomogeneous elemental distribution, whereas XRD reveals a single face-centered cubic phase. Finally, by grinding and re-sintering the specimens, the cation distribution homogeneity is significantly improved, which can simulate spent nuclear fuels with soluble fission products.

Journal Articles

Quantitative visualization of a radioactive plume with harmonizing gamma-ray imaging spectrometry and real-time atmospheric dispersion simulation based on 3D wind observation

Nagai, Haruyasu; Furuta, Yoshihiro*; Nakayama, Hiromasa; Satoh, Daiki

Journal of Nuclear Science and Technology, 60(11), p.1345 - 1360, 2023/11

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

A novel monitoring method for the quantitative visualization of 3D distribution of a radioactive plume and source term estimation of released radionuclides is proposed and its feasibility is demonstrated by preliminary test. The proposed method is the combination of gamma-ray imaging spectroscopy with the Electron Tracking Compton Camera (ETCC) and real-time high-resolution atmospheric dispersion simulation based on 3D wind observation with Doppler lidar. The 3D distribution of a specific radionuclide in a target radioactive plume is inversely reconstructed from line gamma-ray images from each radionuclide by several ETCCs located around the target by harmonizing with the air concentration distribution pattern of the plume predicted by real-time atmospheric dispersion simulation. A prototype of the analysis method was developed, showing a sufficient performance in several test cases using hypothetical data generated by numerical simulations of atmospheric dispersion and radiation transport.

Journal Articles

Extraction of $$^{99}$$Mo hot atoms made by a neutron capture method from $$alpha$$-MoO$$_{3}$$ to water

Quach, N. M.*; Ngo, M. C.*; Yang, Y.*; Nguyen, T. B.*; Nguyen, V. T.*; Fujita, Yoshitaka; Do, T. M. D.*; Nakayama, Tadachika*; Suzuki, Tatsuya*; Suematsu, Hisayuki*

Journal of Radioanalytical and Nuclear Chemistry, 332(10), p.4057 - 4064, 2023/10

 Times Cited Count:0 Percentile:0.01(Chemistry, Analytical)

Technetium-99m ($$^{99m}$$Tc) is the most widely used medical radioisotope in the world and is produced from molybdenum-99 ($$^{99}$$Mo). Production of $$^{99}$$Mo via the neutron capture method draws attention as an alternative to fission-derived $$^{99}$$Mo due to non-proliferation issues, but the specific radioactivity of $$^{99}$$Mo is extremely low. In this work, a porous $$alpha$$-MoO$$_{3}$$ wire was prepared as an irradiation target in order to improve the specific activity by extracting $$^{99}$$Mo. Porous $$alpha$$-MoO$$_{3}$$ wire is synthesized from Mo metal wire by a two-step heating procedure. The hot atom effect of $$^{99}$$Mo was confirmed by activity and isotope measurements of the porous $$alpha$$-MoO$$_{3}$$ wire after neutron irradiation and the water used for extraction. In term of the extraction effectiveness, the effectiveness of $$^{99}$$Mo extraction in the porous $$alpha$$-MoO$$_{3}$$ wire was comparable to that of commercial $$alpha$$-MoO$$_{3}$$ powder.

Journal Articles

Molecular dynamics analysis of reactor graphite for preparing thermal neutron scattering law

Okita, Shoichiro; Goto, Minoru

Proceedings of 12th International Conference on Nuclear Criticality Safety (ICNC2023) (Internet), 10 Pages, 2023/10

Journal Articles

JAEA's action on medical RI production using research reactor

Arai, Masaji; Maeda, Shigetaka

Rinsho Hoshasen, 68(10), p.963 - 970, 2023/10

Ac-225 is attracting attention as an alpha-emitting medical radioisotope. Since its demand is expected to increase, domestic production of Ac-225 is required from the viewpoint of Japan's medical research and economic security. To establish the technical bases for the Ac-225 production, JAEA has evaluated the radioactivity that can be produced in the experimental fast reactor Joyo and designed the concept that upgrades the existing facilities for transporting the irradiated target from Joyo to a neighboring PIE facility rapidly. Efficient Actinium-225 Separation from Ra-226 irradiated in a fast reactor was studied. This study has revealed that Joyo can sufficiently produce Ac-225 as a raw material for pharmaceuticals.

Journal Articles

In situ transmission electron microscopy observation of melted germanium encapsulated in multilayer graphene

Suzuki, Seiya; Nemoto, Yoshihiro*; Shiiki, Natsumi*; Nakayama, Yoshiko*; Takeguchi, Masaki*

Annalen der Physik, 535(9), p.2300122_1 - 2300122_12, 2023/09

 Times Cited Count:0 Percentile:0(Physics, Multidisciplinary)

3190 (Records 1-20 displayed on this page)