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JAEA Reports

Physical property investigation of gloves for glove boxes in nuclear fuel reprocessing plants; Physical properties of used gloves and estimation of its life-time

Yamamoto, Masahiko; Nishida, Naoki; Kobayashi, Daisuke; Nemoto, Ryo*; Hayashi, Hiroyuki*; Kitao, Takahiko; Kuno, Takehiko

JAEA-Technology 2023-004, 30 Pages, 2023/06

JAEA-Technology-2023-004.pdf:1.94MB

Glove-box gloves, that are used for handling nuclear fuel materials at the Tokai Reprocessing Plant (TRP) of the Japan Atomic Energy Agency, have an expiration date by internal rules. All gloves are replaced at a maximum of every 4-year. However, degrees of glove deterioration varies depending on its usage environment such as frequency, chemicals, and radiation dose. Therefore, physical properties such as tensile strength, elongation, hardness of gloves are measured and technical evaluation method for the glove life-time is established. It was found that gloves without any defects in its appearance have enough physical properties and satisfies the acceptance criteria values of new gloves. Thus, it was considered that the expired gloves could be used for total of 8-year, by adding 4-year of new glove life-time. In addition, the results of extrapolation by plotting the glove's physical properties versus the used years showed that the physical properties at 8-year is on the safer side than the reported physical properties of broken glove. Also, the data are not significantly different from the physical properties of the long-term storage glove (8 and 23 years). Based on these results, life-time of gloves at TRP is set to be 8-year. The frequency of glove inspections are not changed, and if any defects is found, the glove is promptly replaced. Thus, the risk related to glove usage is not increased. The cost of purchasing gloves, labor for glove replacement, and the amount of generated waste can be reduced by approximately 40%, respectively, resulting in more efficient and rationalized glove management.

Journal Articles

Regulatory implementation of the occupational equivalent dose limit for the lens of the eye and underlying relevant efforts in Japan

Yokoyama, Sumi*; Hamada, Nobuyuki*; Tsujimura, Norio; Kunugita, Naoki*; Nishida, Kazutaka*; Ezaki, Iwao*; Kato, Masahiro*; Okubo, Hideki*

International Journal of Radiation Biology, 99(4), p.604 - 619, 2023/04

 Times Cited Count:0 Percentile:23.84(Biology)

In April 2011, the International Commission on Radiological Protection recommended reducing the occupational equivalent dose limit for the lens. Such a new occupational lens dose limit has thus far been implemented in many countries, and there are extensive discussions toward its regulatory implementation in other countries. In Japan, discussions in the Japan Health Physics Society (JHPS) began in April 2013 and in Radiation Council in July 2017, and the new occupational lens dose limit was implemented into regulation in April 2021. To share our experience, we have published a series of papers summarizing situations in Japan: the first paper based on information available by early 2017, and the second paper by early 2019. This paper (our third paper of this series) aims to review updated information available by mid-2022, such as regarding regulatory implementation of the new occupational lens dose limit, recent discussions by relevant ministries based on the opinion from the council, establishment process of safety and health management systems, the JHPS guidelines on lens dose monitoring and radiation safety, voluntary countermeasures of the licensees, development of lens dose calibration method, and recent studies on exposure of the lens in nuclear workers and biological effect on the lens.

Journal Articles

Investigation of physical properties of glove for glove-box and estimation of its life-time

Kobayashi, Daisuke; Yamamoto, Masahiko; Nishida, Naoki; Miyoshi, Ryuta; Nemoto, Ryo*; Hayashi, Hiroyuki*; Kato, Keisuke; Nishino, Saki; Kuno, Takehiko; Kitao, Takahiko; et al.

Nihon Hozen Gakkai Dai-18-Kai Gakujutsu Koenkai Yoshishu, p.237 - 240, 2022/07

All gloves attached to glove-box in Tokai Reprocessing Plant have a fixed expiration date and have to be replaced every 4-year. However, degrees of glove deterioration are different depending on its usage environment (frequency, chemicals, radiation, etc.), because of rubber products. Therefore, physical properties such as tensile strength, elongation, hardness of gloves are measured, and the life-time of gloves are estimated. As a result, gloves without any defects in its appearance have enough physical property for acceptance criteria of new glove. The extrapolated physical property of glove is sufficiently larger than the reported values of damaged glove. No deterioration in physical properties of gloves, that are periodically replaced without any defects in its appearance, is observed and the usable life-time of the glove is estimated to be 8 years.

JAEA Reports

Final report on feasibility study of Pu monitoring and solution measurement of high active liquid waste containing fission product at Reprocessing Facility

Sekine, Megumi; Matsuki, Takuya; Suzuki, Satoshi*; Tsutagi, Koichi; Nishida, Naoki; Kitao, Takahiko; Tomikawa, Hirofumi; Nakamura, Hironobu; LaFleur, A.*; Browne, M.*

JAEA-Technology 2019-023, 160 Pages, 2020/03

JAEA-Technology-2019-023.pdf:9.43MB

The International Atomic Energy Agency (IAEA) has proposed in its Research and Development plan (STR-385), the development of technology to enable real-time flow measurement of nuclear material as a part of an advanced approach to effective and efficient safeguards for reprocessing facilities. To address this, Japan Atomic Energy Agency (JAEA) has been tackling development of a new detector to enable monitoring of Pu in solutions with numerous FPs as a joint research program with U.S. DOE to cover whole reprocessing process. In this study, High Active Liquid Waste (HALW) Storage Facility in Tokai Reprocessing Plant was used as the test field. At first, the design information of HALW storage tank and radiation (type and intensity) were investigated to develop a Monte Carlo N-Particle Transport Code (MCNP) model. And then, dose rate distribution outside/ inside of the concrete cell where the HALW tank is located was measured to design new detectors and check MCNP model applicability. Using the newly designed detectors, gamma rays and neutron were continuously measured at the outside/ inside of the concrete cell to assess the radiation characteristics and to optimize detector position. Finally, the applicability for Pu monitoring technology was evaluated based on the simulation results and gamma-ray/neutron measurement results. We have found that there is possibility to monitor the change of Pu amount in solution by combination both of gamma-ray and neutron measurement. The results of this study suggested the applicability and capability of the Pu motoring to enhance safeguards for entire reprocessing facility which handles Pu with FP as a feasibility study. This is final report of this project.

Journal Articles

Replacement of the glove port equipped with glove box in Nuclear Fuel Reprocessing Facility

Horigome, Kazushi; Taguchi, Shigeo; Nishida, Naoki; Goto, Yuichi; Inada, Satoshi; Kuno, Takehiko

Nihon Hozen Gakkai Dai-14-Kai Gakujutsu Koenkai Yoshishu, p.381 - 384, 2017/08

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

Effects of irradiation induced Cu clustering on vickers hardness and electrical resistivity of Fe-Cu model alloys

Tobita, Toru; Nakagawa, Sho*; Takeuchi, Tomoaki; Suzuki, Masahide; Ishikawa, Norito; Chimi, Yasuhiro; Saito, Yuichi; Soneda, Naoki*; Nishida, Kenji*; Ishino, Shiori*; et al.

Journal of Nuclear Materials, 452(1-3), p.241 - 247, 2014/09

 Times Cited Count:15 Percentile:76.9(Materials Science, Multidisciplinary)

Three kinds of Fe-based model alloys, Fe-0.018 atomic percent (at.%) Cu, Fe-0.53at.%Cu, and Fe-1.06at.%Cu were irradiated with 2 MeV electrons up to the dose of 2$$times$$10$$^{-5}$$ dpa at 250$$^{circ}$$C. After the irradiation, the increase in Vickers hardness and the decrease in electrical resistivity were observed. The increase in hardness by electron irradiation is proportional to the product of the Cu contents and the square root of the electron dose. The decrease in electrical resistivity is proportional to the product of the square of Cu contents and the electron dose. Cu clustering in the materials with electron irradiation and thermal aging was observed by means of the three dimensional atom probes (3D-AP). The change in Vickers hardness and electrical resistivity is well correlated with the volume fraction of Cu clusters.

Journal Articles

Restoration of the corrosion department of the reprocessing facilities analysis waste fluid plumbing

Nishida, Naoki; Suwa, Toshio; Tanaka, Naoki; Inada, Satoshi; Kuno, Takehiko

Nihon Hozen Gakkai Dai-11-Kai Gakujutsu Koenkai Yoshishu, p.121 - 126, 2014/07

Corroded pore was found at stainless pipe for liquid waste solution from the analytical laboratory. Part of the pipe was cut for preparing samples to investigate the cause of the corrosion. The same size of stainless pipe was welded to recover it, under the strict radiation control. The restoration work was done inside of the vinyl house, as it is called "greenhouse", which was the small room completely separated by vinyl sheet. All the works, cutting, decontamination, digging groove and welding with back seal gas, were done inside of the greenhouse. We report the work method for recovery of corroded pipe containing radioactive materials

Journal Articles

Investigation into corrosion cause of the reprocessing facilities analysis waste fluid plumbing

Tanaka, Naoki; Suwa, Toshio; Nishida, Naoki; Kuno, Takehiko; Inami, Shinichi

Nihon Hozen Gakkai Dai-11-Kai Gakujutsu Koenkai Yoshishu, p.127 - 131, 2014/07

Corroded pore was found at stainless pipe for liquid waste solution from the analytical laboratory. In order to find out the cause of corrosion, analytical samples were prepared cutting from the pipe. Reagents contained chloride, which had been used analytical laboratory more than ten years before the date, were found to be the trigger of the localized corrosion. We checked up all the pipes, which have been wasted including chloride solutions, by phased array instrument. We report the investigation of cause of corrosion and results of non-destructive testing.

Journal Articles

Hardening induced by energetic electron beam for Cu-Ti alloys

Ueyama, Daichi*; Semboshi, Satoshi*; Saito, Yuichi; Ishikawa, Norito; Nishida, Kenji*; Soneda, Naoki*; Hori, Fuminobu*; Iwase, Akihiro*

Japanese Journal of Applied Physics, 53(5S1), p.05FC04_1 - 05FC04_5, 2014/05

 Times Cited Count:6 Percentile:34.83(Physics, Applied)

In our previous research, it was found that the hardness of Cu-Ti alloy increased by energetic heavy ion irradiation at room temperature. In the conference, we will show the result of electron beam irradiation on the hardness of Cu-Ti alloys. We used CuTi sheets with the dimension of 10 $$times$$ 10 $$times$$ 0.250 mm$$^{3}$$. The specimens were irradiated at 473 K and 523 K with 2 MeV electrons. For comparison, we thermally aged some specimens at the same temperatures as that for the irradiation. The electron fluence of 8.0 $$times$$ 10$$^{17}$$/cm$$^{2}$$ corresponds to the processing time of about 10 h. As a result, the thermal aging for 10 h increases the hardness by 5 or less, which is much smaller than that by the irradiation (about 20). The hardness of the reverse side of irradiated surface is almost the same as that of the irradiated surface. The present result implies that energetic electron irradiation can be a useful tool for controlling the hardness of the "bulk" Cu-Ti alloy.

Journal Articles

Hardness modification of aluminum-alloys by means of energetic ion irradiation and subsequent thermal aging

Mitsuda, Tomoaki*; Kobayashi, Ippei*; Kosugi, Shinya*; Fujita, Naoki*; Saito, Yuichi; Hori, Fuminobu*; Semboshi, Satoshi*; Kaneno, Yasuyuki*; Nishida, Kenji*; Soneda, Naoki*; et al.

Nuclear Instruments and Methods in Physics Research B, 272, p.49 - 52, 2012/02

 Times Cited Count:7 Percentile:52.71(Instruments & Instrumentation)

Journal Articles

Hardening of Al-Cu-Mg alloy by energetic ion irradiation

Mitsuda, Tomoaki*; Kobayashi, Ippei*; Kosugi, Shinya*; Fujita, Naoki*; Saito, Yuichi; Hori, Fuminobu*; Semboshi, Satoshi*; Kaneno, Yasuyuki*; Nishida, Kenji*; Soneda, Naoki*; et al.

Journal of Nuclear Materials, 408(2), p.201 - 204, 2011/01

 Times Cited Count:11 Percentile:66.95(Materials Science, Multidisciplinary)

Journal Articles

Determination of crystal structure and charge density of (Ba$$_{0.5}$$Sr$$_{0.5}$$)(Co$$_{0.8}$$Fe$$_{0.2}$$)O$$_{2.33}$$ by Rietveld refinement and maximum entropy method analysis

Ito, Takanori*; Nishida, Yuki*; Tomita, Aya*; Fujie, Yoshinori*; Kitamura, Naoto*; Idemoto, Yasushi*; Osaka, Keiichi*; Hirosawa, Ichiro*; Igawa, Naoki

Solid State Communications, 149(1-2), p.41 - 44, 2009/01

 Times Cited Count:35 Percentile:77.04(Physics, Condensed Matter)

The crystal structure and charge density of (Ba$$_{0.5}$$Sr$$_{0.5}$$)(Co$$_{0.8}$$Fe$$_{0.2}$$)O$$_{2.33}$$ were investigated by the Rietveld refinement method and the maximum entropy method by using neutron and synchrotron X-ray diffraction. The crystal structure was refined by using the split atom model to cation sites with the space group, ${it Pnma}$. The site occupancies of O1(4${it c}$) and O2(8${it d}$) sites were 0.59 and 0.87, respectively. It was found that the (Co, Fe)-O2 plane in the sample has anisotropic covalent and ionic bands, and that the (Ba, Sr)-O1 bond was ionic with a low charge density.

Oral presentation

Redox behavior of neptunium in pulutonium nitrate solution

Yanagibashi, Futoshi; Nishida, Naoki; Suwa, Toshio; Fujimoto, Ikuo; Obu, Tomoyuki; Kashimura, Takao

no journal, , 

no abstracts in English

Oral presentation

Long annealing effects of (La, Sr)(Co, Fe)O$$_{3-delta}$$ for solid oxide fuel cells cathode materials

Ito, Takanori*; Kurumada, Masamori*; Nishida, Yuki*; Hirai, Takene*; Igawa, Naoki

no journal, , 

We have studied the change of oxygen behavior using by neutron diffractions before and after annealed (La,Sr)(Co,Fe)O$$_{3-delta}$$ (LSCF) synthesized from high or low purity raw materials. The oxygen neutron scattering length density of the high purity LSCF concentrated to the 18${it e}$ site after annealing according to results of the Rietveld refinement and the maximum entropy method. On the other hand, For one of the low purity LSCF, No marked changes were seen. These results suggest that oxygen concentrate to the stable site in the high purity LSCF, on the other hand, the stability of the oxygen in low purity LSCF did not change by annealing.

Oral presentation

Training of chemical analysis technique of radioactive materials in actual field

Masaki, Yuji*; Miyauchi, Hironari*; Taguchi, Shigeo; Horigome, Kazushi; Ishibashi, Atsushi; Yamamoto, Masahiko; Masui, Kenji; Nishida, Naoki; Kuno, Takehiko; Surugaya, Naoki

no journal, , 

Reprocess the technology development center has longtime experience for the handling of the radiation and perform support aiming at the acquisition of the spot analysis technique about the radioactive nuclear material handling in response to a demand out of the mechanism.

Oral presentation

Feasibility study of technology for Pu solution monitoring including FP, 4; Comparison between dose rate measurement result and simulation result

Matsuki, Takuya; Nishida, Naoki; Horigome, Kazushi; Sekine, Megumi; Kitao, Takahiko; Nakamura, Hironobu

no journal, , 

To inquest the measurement point of the detector which can conduct the Pu monitoring in the high active liquid waste at Tokai reprocessing plant, we have made the simulation model which can calculate the radiation distribution in the cell storing HALW. Comparing the dose rate distribution between calculation result and actual measurement result, we evaluated the validity of the current simulation model.

Oral presentation

Analysis of iodine 129 in gaseous radioactive waste at Tokai Reprocessing Plant

Saegusa, Yu; Yamamoto, Masahiko; Nishida, Naoki; Taguchi, Shigeo; Watanabe, Nobuhisa; Inada, Satoshi; Kuno, Takehiko

no journal, , 

Iodine in gaseous radioactive waste at the reprocessing facility is collected on an activated charcoal filter. Iodine129 is measured by radioactive analysis using a Ge semiconductor detector. In this research, the correction method for the influence of self-absorption and iodine recovery is proposed. The influence of self-absorption is evaluated by determining the linear attenuation coefficient of activated charcoal filter. Iodine recovery on the activated charcoal filter is also evaluated by measuring $$gamma$$-ray intensity from both side of the filter.

Oral presentation

Magnetic properties of Bi-doped GdCrO$$_{3}$$

Yoshii, Kenji; Tsuji, Takuya; Matsumura, Daiju; Nishida, Ginichi*; Inoue, Naoki*; Fukada, Yukimasa*; Yaita, Tsuyoshi

no journal, , 

We have investigated the magnetic properties of Bi-doped perovskite GdCrO$$_{3}$$, which was reported to be multiferroic below the magnetic transition temperature (170 K). For the low doping levels (about 5-10% Bi at the Gd site), single-phase samples could be prepared at 920$$^{circ}$$C, a temperature which is much lower than the firing temperature of GdCrO$$_{3}$$ (about 1300-1400$$^{circ}$$C). This result is essentially the same as that of isostructural (Sm,Bi)CrO$$_{3}$$. Magnetic measurements showed that the magnetic properties were essentially identical to those of GdCrO$$_{3}$$. For example, the chromium spins show a ferrimagnetic transition at 170 K. Interestingly, these properties were entirely different from those of (Sm,Bi)CrO$$_{3}$$, which showed that the Bi doping led to a drastic lowering of magnetic transition temperature (by 140 K). We have also conducted X-ray absorption measurements to determine the crystallographic site of Bi. The results will be shown at the conference.

Patent

グローブポートの交換方法及びグローブポート交換治具

堀籠 和志; 後藤 雄一; 西田 直樹; 山本 昌彦

not registered

JP, 2020-048011  Patent licensing information  Patent publication (In Japanese)

【課題】グローブボックス内の汚染物質の漏洩を防止したうえで、短時間且つ低コストでグローブポートを交換する方法を提供する。 【解決手段】グローブポートの交換方法は、グローブパネルに第1外側ボックス及び第1内側ボックスを取り付ける第1取付工程と、グローブポートを構成する複数の部品を第1外側ボックス側又は第1内側ボックス側に取り外すポート取外工程と、閉止板で取付開口を閉止する閉止工程と、第1外側ボックス及び第1内側ボックスを取り外す第1取外工程と、グローブパネルに第2外側ボックス及び第2内側ボックスを取り付ける第2取付工程と、取付開口を開放する開放工程と、第2外側ボックス及び第2内側ボックス内の部品で新たなグローブポートを構成するポート取付工程と、第2外側ボックス及び第2内側ボックスを取り外す第2取外工程とを含む。

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