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Journal Articles

Study of the $$N=32$$ and $$N=34$$ shell gap for Ti and V by the first high-precision multireflection time-of-flight mass measurements at BigRIPS-SLOWRI

Iimura, Shun*; Rosenbusch, M.*; Takamine, Aiko*; Tsunoda, Yusuke*; Wada, Michiharu*; Chen, S.*; Hou, D. S.*; Xian, W.*; Ishiyama, Hironobu*; Yan, S.*; et al.

Physical Review Letters, 130(1), p.012501_1 - 012501_6, 2023/01

Journal Articles

Rapid analysis of $$^{90}$$Sr in cattle bone and tooth samples by inductively coupled plasma mass spectrometry

Koarai, Kazuma; Matsueda, Makoto; Aoki, Jo; Yanagisawa, Kayo*; Terashima, Motoki; Fujiwara, Kenso; Kino, Yasushi*; Oka, Toshitaka; Takahashi, Atsushi*; Suzuki, Toshihiko*; et al.

Journal of Analytical Atomic Spectrometry, 36(8), p.1678 - 1682, 2021/08

 Times Cited Count:2 Percentile:40.3(Chemistry, Analytical)

Rapid analysis of $$^{90}$$Sr in bone and tooth samples of cattle were achieved by an inductively coupled plasma mass spectrometry (ICP-MS) coupled with mass shift and solid phase extraction techniques. Limit of detection (LOD) in the ICP-MS measurement of 0.1 g samples was lower than that of the radioactivity measurement. Analytical time of the ICP-MS method was reduced from 20 days to 11 hours, compared with the radiometric method. Therefore, the ICP-MS method can be rapid and useful procedure of $$^{90}$$Sr in small bone and tooth samples derived from terrestrial animals.

Journal Articles

Online solid-phase extraction-inductively coupled plasma-quadrupole mass spectrometry with oxygen dynamic reaction for quantification of technetium-99

Matsueda, Makoto; Yanagisawa, Kayo*; Koarai, Kazuma; Terashima, Motoki; Fujiwara, Kenso; Abe, Hironobu; Kitamura, Akihiro; Takagai, Yoshitaka*

ACS Omega (Internet), 6(29), p.19281 - 19290, 2021/07

 Times Cited Count:1 Percentile:12.84(Chemistry, Multidisciplinary)

Online solid-phase extraction-inductively coupled plasma-quadrupole mass spectrometry with oxygen dynamic reaction cell (online SPE-ICP-MS-DRC) was shown to be a thorough automatic analytical system, circumventing the need for human handling. At three stepwise separations (SPE-DRC-Q mass filters), we showed that interference materials allowed the coexistence of abundance ratios of 1.5$$times$$10$$^{-13}$$ for $$^{99}$$Tc/Mo. Using this optimized system, a detection limit of $$^{99}$$Tc was 9.3 pg/L (5.9 mBq/L) for a 50 mL injection and sequential measurements were undertaken at a cycle of 24 min/sample.

JAEA Reports

Development of solid-phase extraction technique for ICP-MS analysis of iodine-129 in environmental samples; Comparative study of anion-exchange and silver ion-supported resins on isolation of Iodine-129 from interference elements

Aoki, Jo; Matsueda, Makoto; Koarai, Kazuma; Terashima, Motoki; Fujiwara, Kenso; Abe, Hironobu

JAEA-Research 2021-002, 20 Pages, 2021/05


In order to analyze extremely low concentrations of $$^{129}$$I in environmental samples by ICP-MS with high sensitivity and rapidity, it is necessary to remove interfering elements (Na, Mg, K, Ca, Mo, Cd and In) using a pretreatment method with Solid-phase Extraction Resin. Anion Exchange Resins with amino groups have been widely used as Solid-phase Extraction Resins, while Ag+ Supported Resins have also been widely used in recent years. It is necessary to optimize the pretreatment technique based on characteristics of the resins. In this study, we compared in terms of separation of I from matrix elements (Na, Mg, K, Ca, Mo, Cd and In) for DOWEX1-X8, AG 1-X8 and CL Resin, and investigated their suitability for ICP-MS analysis of $$^{129}$$I in environmental samples. The results of adsorption and elution experiments showed that all resins examined uptake and elute I quantitatively. CL Resin showed the highest removal performance of interfering elements, with 3.1% of Mo remaining, but other interfering elements were removed below the detection limit of ICP-MS. However, the Mo remained after the CL Resin treatment could interfere the ICP-MS measurement of $$^{129}$$I, based on the consideration of ratio of $$^{129}$$I and Mo. The eluate from CL Resin was treated with a Cation exchange resin (DOWEX 50WX8). As a result, Mo in the eluate was removed by up to 98% and the interference from Mo was reduced to measurable level. Therefore, the pretreatment method using CL Resin in combination with DOWEX 50WX8 is effective for ICP-MS analysis of $$^{129}$$I at extremely low concentrations (background level).

Journal Articles

Applicability of Sr resin for ICP-MS measurement of $$^{90}$$Sr in hard tissue samples

Koarai, Kazuma; Matsueda, Makoto; Aoki, Jo; Yanagisawa, Kayo*; Fujiwara, Kenso; Terashima, Motoki; Kitamura, Akihiro; Abe, Hironobu

KEK Proceedings 2020-4, p.180 - 185, 2020/11

Strontium-90 and $$^{90}$$Y, its daughter nuclide, adverse effects on the bone marrow. Monitoring of $$^{90}$$Sr in the bones have been required after the Fukushima-Daiichi Nuclear Power Plant accident. However, conventional radioactivity measurement method for $$^{90}$$Sr requires a complicated separation of $$^{90}$$Y and a time-consuming measurement. ICP-MS system has been applied to $$^{90}$$Sr concentration survey of water, soil, and edible part of fish. We applied the ICP-MS system for the bones for the first time. In this study, reference bone (JSAC 0785 fish bone) was used as measurement samples. Sample preparation of the bone was performed using a microwave digestion instrument. After sample preparation, $$^{90}$$Sr was determined using ICP-MS system with cascade separation steps based on on-line column separation and oxygen reaction. Strontium-90 in the bones was successfully separated from Ca, Ba, Y, Zr, Fe, Se, and Ge, which interfered in ICP-MS measurement, in the separation steps.

JAEA Reports

A Study for a fire gas behavior by using a vertical shaft model (Contract research)

Abe, Hironobu; Hatakeyama, Nobuya; Yamazaki, Masanao; Okuzono, Akihiko*; Sakai, Tetsuo*; Inoue, Masahiro*

JAEA-Research 2009-019, 192 Pages, 2020/02


Construction of the underground facility is on going at the Horonobe Underground Research Center, a division of the Japan Atomic Energy Agency. The facility is consisted of three shafts and horizontal drifts at the completion of construction and it is excavated in geological environment with methane gas, so it is important to secure the workers and visitors security in case of fire in the underground. However, it is known that the fire gas such as methane shows a complicated behavior by drift effect and so on and very difficult to predict its behavior, even if under enforced ventilation. In order to construct new prediction method of the fire gas behavior, the model scaled experiments were conducted by using the basic model which consists of shafts and drifts. As a results, fundamental data of the fire gas behavior was grasped and complicated behavior of the fire gas such as three-dimensional backflow and main flow inversion phenomena at the underground structure were ascertained. A new fire gas behavior analysis system has been designed and a prototype system has been programmed which is able to simulate the phenomena noted above. Coupling analysis method is adapted to the system, which consists of mainly one-dimensional ventilation network analysis and simplified computational fluid dynamics program named M-CFD. To minimize calculation time, M-CFD was designed as two-dimensional calculation with simulators multi area analysis system. Using the prototype system, several experimented models representing typical behavior of fire gas have been simulated for model scaled experiments. The system qualitatively reappeared the phenomena such as back flow or main flow inversion, and most of calculations completed in expected time. This indicates appropriateness of the prototype system, but some upgrade such as heat conductivity analysis in the wall rock mass transfer calculation, user friendly interface system and others will be required.

Journal Articles

Demonstration of $$gamma$$-ray pipe-monitoring capabilities for real-time process monitoring safeguards applications in reprocessing facilities

Rodriguez, D.; Tanigawa, Masafumi; Nishimura, Kazuaki; Mukai, Yasunobu; Nakamura, Hironobu; Kurita, Tsutomu; Takamine, Jun; Suzuki, Satoshi*; Sekine, Megumi; Rossi, F.; et al.

Journal of Nuclear Science and Technology, 55(7), p.792 - 804, 2018/07

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

Nuclear material in reprocessing facilities is safeguarded by random sample verification with additional continuous monitoring applied to solution masses and volume in important tanks to maintain continuity-of-knowledge of process operation. Measuring the unique $$gamma$$ rays of each solution as the material flows through pipes connecting all tanks and process apparatuses could potentially improve process monitoring by verifying the compositions in real time. We tested this $$gamma$$ ray pipe-monitoring method using plutonium-nitrate solution transferred between tanks at the PCDF-TRP. The $$gamma$$ rays were measured using a lanthanum-bromide detector with a list-mode data acquisition system to obtain both time and energy of $$gamma$$-ray. The analysis and results of this measurement demonstrate an ability to determine isotopic composition, process timing, flow rate, and volume of solution flowing through pipes, introducing a viable capability for process monitoring safeguards verification.

Journal Articles

$$gamma$$-ray pipe monitoring for comprehensive safeguards process monitoring of reprocessing facilities

Rodriguez, D.; Tanigawa, Masafumi; Mukai, Yasunobu; Isomae, Hidemi; Nakamura, Hironobu; Rossi, F.; Koizumi, Mitsuo; Seya, Michio

Proceedings of INMM 58th Annual Meeting (Internet), 9 Pages, 2017/07

Safegaurding nuclear material at reprocessing facilities utilizes sampling to verify the quantity and process monitoring to maintain continuity-of-knowledge to reduce re-verification. Solution Monitoring and Measurement Systems that determine the solution density and volume are installed at solution tanks, though this only provides indirect verification. To offset this safeguards limitation we propose measuring $$gamma$$ rays from solutions passing through the pipes and at the tanks to provide improved continuous monitoring and direct verification. This can provide both real-time flow measurements and Pu isotopic composition quantification through passive nondestructive assay. This concept was tested by recent experimental studies performed at the Japan Atomic Energy Agency's Plutonium Conversion Development Facility of flowing Pu-nitrate $$gamma$$ rays. This presentation will describe the concept details and analysis of using $$gamma$$ ray pipe monitoring as a capability for real-time safeguards verification.

Journal Articles

Completion of solidification and stabilization for Pu nitrate solution to reduce potential risks at Tokai Reprocessing Plant

Mukai, Yasunobu; Nakamichi, Hideo; Kobayashi, Daisuke; Nishimura, Kazuaki; Fujisaku, Sakae; Tanaka, Hideki; Isomae, Hidemi; Nakamura, Hironobu; Kurita, Tsutomu; Iida, Masayoshi*; et al.

Proceedings of 2017 International Congress on Advances in Nuclear Power Plants (ICAPP 2017) (CD-ROM), 8 Pages, 2017/04

TRP has stored the plutonium in solution state for long-term since the last PCDF operation in 2007 was finished. After the great east Japan earthquake in 2011, JAEA had investigated the risk against potential hazard of these solutions which might lead to make hydrogen explosion and/or boiling of the solution accidents with the release of radioactive materials to the public when blackout. To reduce the risk for storing Pu solution (about 640 kg Pu), JAEA planned to perform the process operation for the solidification and stabilization of the solution by converted into MOX powder at PCDF in 2013. In order to perform PCDF operation without adaption of new safety regulation, JAEA conducted several safety measures such as emergency safety countermeasures, necessary security and safeguards (3S) measures with understanding of NRA. As a result, the PCDF operation had stared on 28th April, 2014, and successfully completed to convert MOX powder on 3rd August, 2016 for about 2 years as planned.

Journal Articles

Development and implementation of GloveBox Cleanout Assistance Tool (BCAT) to detect the presence of MOX by computational approach

Nakamura, Hironobu; Nakamichi, Hideo; Mukai, Yasunobu; Hosoma, Takashi; Kurita, Tsutomu; LaFleur, A. M.*

Proceedings of International Conference on Mathematics & Computational Methods Applied to Nuclear Science & Engineering (M&C 2017) (USB Flash Drive), 7 Pages, 2017/04

In order to maintain facility nuclear material accountancy (NMA) and safeguards properly, to understand where and how much holdup deposit in the process is presence is very important for the cleanout before PIT. JAEA and LANL developed a GloveBox Cleanout Assistance Tool (BCAT) to help cleanout (MOX powder recovering in a glovebox) for invisible holdup effectively by computational approach which is called distributed source-term approach (DSTA). The BCAT tool is a simple neutron measurement slab detectors and helps operator to find locations of holdup. To know the holdup location and the activity from the neutron measurements, the relation between BCAT measurements results at predetermined positions (57 positions) and source voxels (53 voxels) that we want to know the holdup activity was mathematically defined as a matrix by the MCNPX simulation. The model of MCNPX for entire process is very precisely established. We have implemented and experimentally proved that the BCAT tool can direct the operator to recoverable holdup that would otherwise be accounted for as MUF. Reducing facility MUF results in a direct improvement of the facility NMA. The BCAT enables the staff to significantly improve their knowledge of the locations of residual holdup in the process area. JAEA would like to use this application for dismantling of the glovebox with transparency in the future.

Journal Articles

Field test and evaluation of $$^{3}$$He replacement technologies; Development of HLNB counter

Tanigawa, Masafumi; Mukai, Yasunobu; Nakamura, Hironobu; Kurita, Tsutomu; Henzlova, D.*; Menlove, H. O.*

Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2017/02

no abstracts in English

Journal Articles

Operator's contribution on the improvement of inspection scheme for the PCDF operation

Shimizu, Yasuyuki; Makino, Risa; Mukai, Yasunobu; Ishiyama, Koichi; Kurita, Tsutomu; Nakamura, Hironobu

Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2017/02

no abstracts in English

Journal Articles

Field test of a full scale $$^{3}$$He-alternative HLNC-type counter; High Level Neutron counter-Boron (HLNB)

Henzlova, D.*; Menlove, H. O.*; Tanigawa, Masafumi; Mukai, Yasunobu; Nakamura, Hironobu

EUR-28795-EN (Internet), p.313 - 323, 2017/00

Facing the depletion of $$^{3}$$He gas supply and the continuing uncertainty of options for future resupply, Los Alamos National Laboratory (LANL) designed and built a $$^{3}$$He free full scale thermal neutron coincidence counter based on boron-lined parallel-plate proportional technology. The counter was designed as a direct alternative to High Level Neutron Coincidence counter (HLNC-II). This paper provides a summary of performance evaluation of HLNB under realistic field conditions at Plutonium Conversion Development Facility (PCDF) of Japan Atomic Energy Agency (JAEA). The field test included a range of small to large mass MOX materials that represent realistic process samples and provided key insight on and validation of the feasibility of HLNB as a safeguards instrument in realistic facility environment. In particular, the results of verification measurements demonstrate that HLNB is capable to satisfy ITV expected for HLNC-II-type counter of 2.1% in 300s measurement time.

Journal Articles

Development of alternative $$^3$$He NDA detector system

Koizumi, Mitsuo; Sakasai, Kaoru; Kureta, Masatoshi; Nakamura, Hironobu

Nihon Genshiryoku Gakkai-Shi ATOMO$$Sigma$$, 58(11), p.642 - 646, 2016/11

no abstracts in English

Journal Articles

Feasibility study of technology for Pu solution monitoring including FP; Composition research of high active liquid waste and radiation measurement results on the surface of cell

Matsuki, Takuya; Masui, Kenji; Sekine, Megumi; Tanigawa, Masafumi; Yasuda, Takeshi; Tsutagi, Koichi; Ishiyama, Koichi; Nishida, Naoki; Horigome, Kazushi; Mukai, Yasunobu; et al.

Proceedings of INMM 57th Annual Meeting (Internet), 9 Pages, 2016/07

The International Atomic Energy Agency (IAEA) has proposed in its long-term research and development (R&D) plan, development of a real-time measurement technology to monitor and verify nuclear material movement continuously as part of an advanced approach to effectively and efficiently conduct safeguards for reprocessing facilities. Since the Tokai Reprocessing Plant (TRP) has solutions containing both Pu and fission products (FP), a new detector development project to monitor Pu with FP is being carried out from 2015 to 2017. This project is mainly conducted in the High Active Liquid Waste Storage (HALWS) in the TRP. For the first step of this project, as the confirmation of composition of high active liquid waste (HALW) to evaluate neutron/$$gamma$$-ray emitted from solution in the selected HALW tank which has the most amount of Pu in HALW tanks at the TRP, we took HALW sample and conducted $$gamma$$-ray spectrum measurement for HALW. As a study of detector setting location, to survey the available neutron/$$gamma$$-ray (i.e. intensity) at the outside surface of the cell where HALW tank is located, we implemented continuous measurement by neutron/$$gamma$$-ray detector. In this paper, we report three $$gamma$$-ray peaks related with $$^{238}$$Pu and $$^{239}$$Pu measured in the composition research of HALW, which is needed to identify Pu amount by the new detector that we are developing and the result of radiation measurement on the surface of the cell.

Journal Articles

Operator's contribution on the improvement of RII scheme against the process operation at PCDF

Nakamura, Hironobu; Shimizu, Yasuyuki; Makino, Risa; Mukai, Yasunobu; Ishiyama, Koichi; Kurita, Tsutomu; Ikeda, Atsushi*; Yamaguchi, Katsuhiro*

Proceedings of INMM 57th Annual Meeting (Internet), 9 Pages, 2016/07

Regarding the Integrated Safeguards (IS) in Japan, the implementation of IS has been started on September 2004, and the concept has been introduced to the JNC-1 facilities since August 2008. Then, random interim inspection with short notice and reducing person-days of inspection (PDI) was introduced instead of traditional scheduled IIV in order to improve deterrence of the nuclear material diversion with timeliness goal. And it was agreed that it should be evaluated and reviewed because RII was designed when inter-campaign. In JAEA, we decided to restart PCDF campaign to reduce potential safety risks of reprocessing facilities. To adopt the RII scheme to the process operation in campaign, JAEA proposed a new scheme to JSGO and IAEA without increasing PDI and reducing detection probability. As a result of the discussion, it was agreed and successfully introduced since March 2014. The new scheme for PCDF consists of scheduled inspection (fixed-day RII), reduction of estimated material for the verification, implementation of remote monitoring with data provision, improvement of operational status check list, introduction of NRTA and MC&A data declaration with timeliness. Though the operator's workloads for information provision were increased, we could manage to balance IS requirement with implementation of our operation successfully. This contribution was helped to safeguards implementation and our operation for 2 years.

Journal Articles

Feasibility study of technology for Pu solution monitoring including FP; Overview and research plan

Sekine, Megumi; Matsuki, Takuya; Tanigawa, Masafumi; Tsutagi, Koichi; Mukai, Yasunobu; Shimizu, Yasuyuki; Nakamura, Hironobu; Tomikawa, Hirofumi

Proceedings of INMM 57th Annual Meeting (Internet), 9 Pages, 2016/07

The International Atomic Energy Agency (IAEA) has proposed in its long-term research and development plan, development of a real-time measurement technology to monitor and verify nuclear material movement continuously as part of an advanced approach to effectively and efficiently conduct safeguards for reprocessing facilities. In the reprocessing plant, since solutions containing both Pu and FP exist, a new detector development project to monitor Pu with FP is being carried out from 2015 to 2017. This project is mainly conducted in the High Active Liquid Waste Storage (HALWS) in Tokai Reprocessing Plant (TRP). In this paper, an overview of the technology development, simulation results of preliminary evaluation of the characteristics of radiation emitted from the HALW tank at TRP, and the future research plan are presented.

Journal Articles

Development of active neutron NDA techniques for nuclear nonproliferation and nuclear security, 7; Measurement of DG from MOX and Pu liquid samples for quantification and monitoring

Mukai, Yasunobu; Ogawa, Tsuyoshi; Nakamura, Hironobu; Kurita, Tsutomu; Sekine, Megumi; Rodriguez, D.; Takamine, Jun; Koizumi, Mitsuo; Seya, Michio

Proceedings of INMM 57th Annual Meeting (Internet), 7 Pages, 2016/07

The development of Delayed Gamma-ray Spectroscopy (DGS) for analyzing the composition ratio of fissile nuclides ($$^{239}$$Pu, $$^{241}$$Pu, $$^{235}$$U) focused on the Delayed Gamma-ray having energy over 3 MeV has been performed for the development of active neutron non-destructive assay techniques. In PCDF, measurement tests of Delayed Gamma-ray using Pu solution and MOX powder samples to prove the DGS technique is planned to be performed in following 4 stages. (1) Measurements for Delayed Gamma-ray originated from spontaneous fission nuclide (Passive), (2) Measurements for the Delayed Gamma-ray with fast neutron (Active), (3) DGSI (DGS combined with self-interrogation) measurements (Passive), (4) Measurements for the Delayed Gamma-ray with thermal neutron (Active) In this paper, the plan of measurement tests for nuclear material samples with use of DGS is presented.

Journal Articles

Direct measurement of nanoscale lithium diffusion in solid battery materials using radioactive tracer of $$^{8}$$Li

Ishiyama, Hironobu*; Jeong, S.-C.*; Watanabe, Yutaka*; Hirayama, Yoshikazu*; Imai, Nobuaki*; Jung, H. S.*; Miyatake, Hiroari*; Oyaizu, Mitsuhiro*; Osa, Akihiko; Otokawa, Yoshinori; et al.

Nuclear Instruments and Methods in Physics Research B, 376, p.379 - 381, 2016/06

 Times Cited Count:7 Percentile:59.04(Instruments & Instrumentation)

Journal Articles

Demonstration result of sample assay system equipped alternative He-3 detectors

Tanigawa, Masafumi; Mukai, Yasunobu; Tobita, Hiroshi; Kurata, Noritaka*; Kobayashi, Nozomi*; Takase, Misao*; Makino, Risa; Ozu, Akira; Nakamura, Hironobu; Kurita, Tsutomu; et al.

56th Annual Meeting of the Institute of Nuclear Materials Management (INMM 2015), Vol.1, p.693 - 701, 2016/00

no abstracts in English

147 (Records 1-20 displayed on this page)