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Stochastic estimation of radionuclide composition in wastes generated at Fukushima Daiichi Nuclear Power Station using Bayesian inference

杉山 大輔*; 中林 亮*; 田中 真悟*; 駒 義和; 高畠 容子

Journal of Nuclear Science and Technology, 58(4), p.493 - 506, 2021/04

 被引用回数:0 パーセンタイル:0.01(Nuclear Science & Technology)

A modeling calculation methodology for estimating the radionuclide composition in the wastes generated at the Fukushima Daiichi nuclear power station has been upgraded by introducing an approach using Bayesian inference. The developed stochastic method describes the credible interval of the regression curve for the log-normal distribution of the measured transport ratio, which is used to calibrate the radionuclide transport parameters included in the modeling calculation. Consequently, the method can predict the robability distribution of the radionuclide composition in the Fukushima Daiichi wastes. The notable feature of the developed method is that it can explicitly investigate the improvement in the accuracy and confidence (degree of belief) of the estimation of the waste inventory using Bayesian inference. Specifically, the developed method can update and improve the degree of belief of the estimation of the radionuclide composition by visualizing the reduction in the width of uncertainty in the radionuclide transport parameters in the modeling calculation in accordance with the accumulation of analytically measured data. Further investigation is expected to improve the credibility of waste inventory estimation through iteration between modeling calculations and analytical measurements and to reduce excessive conservativeness in the estimated waste inventory dataset.


High temperature gas-cooled reactors

武田 哲明*; 稲垣 嘉之; 相原 純; 青木 健; 藤原 佑輔; 深谷 裕司; 後藤 実; Ho, H. Q.; 飯垣 和彦; 今井 良行; et al.

High Temperature Gas-Cooled Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.5, 464 Pages, 2021/02



Image-based view selection for shape comparison of mode water regions in virtual reality spaces

矢野 緑里; 伊藤 貴之*; 田中 裕介*; 松岡 大祐*; 荒木 文明*; Czauderna, T.*; Stephens, K.*

Proceedings of Joint International Conference on Supercomputing in Nuclear Applications + Monte Carlo 2020 (SNA + MC 2020), p.201 - 208, 2020/10



Observation of morphological abnormalities in silkworm pupae after feeding $$^{137}$$CsCl-supplemented diet to evaluate the effects of low dose-rate exposure

田中 草太; 木野内 忠稔*; 藤井 告*; 今中 哲二*; 高橋 知之*; 福谷 哲*; 牧 大介*; 納冨 昭弘*; 高橋 千太郎*

Scientific Reports (Internet), 10, p.16055_1 - 16055_7, 2020/09

 被引用回数:1 パーセンタイル:40.2(Multidisciplinary Sciences)



Production of $$^{266}$$Bh in the $$^{248}$$Cm($$^{23}$$Na,5$$n$$)$$^{266}$$Bh reaction and its decay properties

羽場 宏光*; Fan, F.*; 加治 大哉*; 笠松 良崇*; 菊永 英寿*; 小森 有希子*; 近藤 成美*; 工藤 久昭*; 森本 幸司*; 森田 浩介*; et al.

Physical Review C, 102(2), p.024625_1 - 024625_12, 2020/08

 被引用回数:2 パーセンタイル:57.67(Physics, Nuclear)

The nuclide $$^{266}$$Bh was produced in the $$^{248}$$Cm($$^{23}$$Na,5n)$$^{266}$$Bh reaction at beam energies of 125.9, 130.6, and 135.3 MeV. Decay properties of $$^{266}$$Bh were investigated with a rotating wheel apparatus for $$alpha$$ and spontaneous fission (SF) spectrometry under low background conditions attained by a gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator. The half-life of $$^{266}$$Bh was measured to be $$T_{rm 1/2}$$ = 10.0$$^{+2.6}_{-1.7}$$ s. The $$alpha$$-particle energies of $$^{266}$$Bh disperse widely in the range of 8.62 - 9.40 MeV. The maximum production cross section for the $$^{248}$$Cm($$^{23}$$Na,5n)$$^{266}$$Bh reaction was determined to be $$sigma$$ = 57 $$pm$$ 14 pb at 130.6 MeV.


Detailed structural study on the poly(vinyl alcohol) adsorption layers on a Si substrate with solvent vapor-induced swelling

宮崎 司*; 宮田 登*; 吉田 鉄生*; 有馬 寛*; 津村 佳弘*; 鳥飼 直也*; 青木 裕之; 山本 勝宏*; 金谷 利治*; 川口 大輔*; et al.

Langmuir, 36(13), p.3415 - 3424, 2020/04

 被引用回数:6 パーセンタイル:75.63(Chemistry, Multidisciplinary)

We investigated in detail the structures in the poly(vinyl alcohol) (PVA) adsorption layers on a Si substrate, which remained on the substrate after immersing the relatively thick 30 - 50 nm films in hot water, by neutron reflectometry under humid conditions. For the PVA with a degree of saponification exceeding 98 mol %, the adsorption layer exhibits a three-layered structure in the thickness direction. The bottom layer is considered to be the so-called inner adsorption layer that is not fully swollen with water vapor. This may be because the polymer chains in the inner adsorption layer are strongly constrained onto the substrate, which inhibits water vapor penetration. The polymer chains in this layer have many contact points to the substrate via the hydrogen bonding between the hydroxyl groups in the polymer chain and the silanol groups on the surface of the Si substrate and consequently exhibit extremely slow dynamics. Therefore, it is inferred that the bottom layer is fully amorphous. Furthermore, we consider the middle layer to be somewhat amorphous because parts of the molecular chains are pinned below the interface between the middle and bottom layers. The molecular chains in the top layer become more mobile and ordered, owing to the large distance from the strongly constrained bottom layer; therefore, they exhibit a much lower degree of swelling compared to the middle amorphous layer. Meanwhile, for the PVA with a much lower degree of saponification, the adsorption layer structure consists of the two-layers. The bottom layer forms the inner adsorption layer that moderately swells with water vapor because the polymer chains have few contact points to the substrate. The molecular chains in the middle layer, therefore, are somewhat crystallizable because of this weak constraint.


Elucidation of a heterogeneous layered structure in the thickness direction of poly(vinyl alcohol) films with solvent vapor-induced swelling

宮崎 司*; 宮田 登*; 浅田 光則*; 津村 佳弘*; 鳥飼 直也*; 青木 裕之; 山本 勝宏*; 金谷 利治*; 川口 大輔*; 田中 敬二*

Langmuir, 35(34), p.11099 - 11107, 2019/08

 被引用回数:10 パーセンタイル:68.76(Chemistry, Multidisciplinary)

We investigated the swelling behaviors of poly(vinyl alcohol) (PVA) films deposited on Si wafers with water vapor, which is a good solvent for PVA for elucidating structural and dynamical heterogeneities in the film thickness direction. Using deuterated water vapor, structural and dynamical differences in the thickness direction can be detected easily as different degrees of swelling in the thickness direction by neutron reflectivity. Consequently, the PVA film with a degree of saponification exceeding 98 mol % exhibits a three-layered structure in the thickness direction. It is considered that an adsorption layer consisting of molecular chains that are strongly adsorbed onto the solid substrate is formed at the interface with the substrate, which is not swollen with water vapor compared with the bulk-like layer above it. The adsorption layer is considered to exhibit significantly slower dynamics than the bulk. Furthermore, a surface layer that swells excessively compared with the underneath bulk-like layer is found. This excess swelling of the surface layer may be related to a higher mobility of the molecular chains or lower crystallinity at the surface region compared to the underneath bulk-like layer. Meanwhile, for the PVA film with a much lower degree of saponification, a thin layer with a slightly lower degree of swelling than the bulk-like layer above it can be detected at the interface between the film and substrate only under a high humidity condition. This layer is considered to be the adsorption layer composed of molecular chains loosely adsorbed onto the Si substrate.


Study on evaluation method for entrained gas flow rate by free surface vortex

伊藤 啓*; 伊藤 大介*; 齊藤 泰司*; 江連 俊樹; 松下 健太郎; 田中 正暁; 今井 康友*

Proceedings of 18th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-18) (USB Flash Drive), p.6632 - 6642, 2019/08



Localized magnetic excitations in the fully frustrated dimerized magnet Ba$$_{2}$$CoSi$$_{2}$$O$$_{6}$$Cl$$_{2}$$

栗田 伸之*; 山本 大輔*; 金坂 拓哉*; 古川 信夫*; 河村 聖子; 中島 健次; 田中 秀数*

Physical Review Letters, 123(2), p.027206_1 - 027206_6, 2019/07

 被引用回数:2 パーセンタイル:35.62(Physics, Multidisciplinary)

Magnetic excitations of the effective spin $$S$$ =1/2 dimerized magnet Ba$$_{2}$$CoSi$$_{2}$$O$$_{6}$$Cl$$_{2}$$ have been probed directly via inelastic neutron scattering experiments. We observed five types of excitation, which are all dispersionless within the resolution limits. The scattering intensities of the three low-lying excitations were found to exhibit different $$Q$$-dependences. Detailed analysis has demonstrated that Ba$$_{2}$$CoSi$$_{2}$$O$$_{6}$$Cl$$_{2}$$ is a two dimensional spin dimer system described only by a single dimer site, where the triplet excitations are localized owing to the almost perfect frustration of the interdimer exchange interactions and the undimerized spins, even in small concentration, make an essential contribution to the excitation spectrum.


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

向 泰宣; 中道 英男; 小林 大輔; 西村 和明; 藤咲 栄; 田中 秀樹; 磯前 日出海; 中村 仁宣; 栗田 勉; 飯田 正義*; et al.

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



New muonium HFS measurements at J-PARC/MUSE

Strasser, P.*; 青木 正治*; 深尾 祥紀*; 東 芳隆*; 樋口 嵩*; 飯沼 裕美*; 池戸 豊*; 石田 啓一*; 伊藤 孝; 岩崎 雅彦*; et al.

Hyperfine Interactions, 237(1), p.124_1 - 124_9, 2016/12

 被引用回数:6 パーセンタイル:92.96

At the Muon Science Facility (MUSE) of J-PARC (Japan Proton Accelerator Research Complex), the MuSEUM collaboration is planning new measurements of the ground state hyperfine structure (HFS) of muonium both at zero field and at high magnetic field. The previous measurements were performed both at LAMPF (Los Alamos Meson Physics Facility) with experimental uncertainties mostly dominated by statistical errors. The new high intensity muon beam that will soon be available at MUSE H-Line will provide an opportunity to improve the precision of these measurements by one order of magnitude. An overview of the different aspects of these new muonium HFS measurements, the current status of the preparation, and the results of a first commissioning test experiment at zero field are presented.


Simultaneous analysis of silicon and boron dissolved in water by combination of electrodialytic salt removal and ion-exclusion chromatography with corona charged aerosol detection

森 勝伸*; 佐柄 克哉*; 新井 香織*; 中谷 暢丈*; 大平 慎一*; 戸田 敬*; 板橋 英之*; 小崎 大輔*; 須郷 由美; 渡辺 茂樹; et al.

Journal of Chromatography A, 1431, p.131 - 137, 2016/01

 被引用回数:8 パーセンタイル:44.25(Biochemical Research Methods)

Selective separation and sensitive detection of dissolved silicon and boron (DSi and DB) in aqueous solution was achieved by connecting an electrodialytic ion isolation device (EID), an ion-exclusion chromatography (IEC) column, and a corona charged aerosol detector (CCAD) in sequence. They were separated by IEC using pure water eluent. Detection of DSi and DB by the CCAD was effective for much greater sensitivity than by conductimetric detection. The EID removed salt from the sample prior to the IEC-CCAD. The combination of EID, IEC and CCAD successfully separated and determined DSi and DB in artificial seawater and hot-spring water samples by eluting pure water.


Synthesis, direct formation under high pressure, structure, and electronic properties of LiNbO$$_{3}$$-type oxide PbZnO$$_{3}$$

森 大輔*; 田中 樹恵*; 齋藤 寛之; 亀卦川 卓美*; 稲熊 宜之*

Inorganic Chemistry, 54(23), p.11405 - 11410, 2015/12

 被引用回数:16 パーセンタイル:72.19(Chemistry, Inorganic & Nuclear)

A novel LiNbO$$_{3}$$-type (LN-type) lead zinc oxide, PbZnO$$_{3}$$, was successfully synthesized under high pressure and temperature. Rietveld structure refinement using synchrotron powder X-ray diffraction (XRD) data demonstrated that LN-type PbZnO$$_{3}$$ crystallized into a trigonal structure with a polar space group ($$R3c$$).


Simple method for high-density impregnation of Aliquat 336 onto porous sheet and binding performance of resulting sheet for palladium ions

田中 亮太*; 石原 量*; 三好 和義*; 梅野 太輔*; 斎藤 恭一*; 浅井 志保; 山田 伸介*; 廣田 英幸*

Separation Science and Technology, 49(1), p.154 - 159, 2014/01

 被引用回数:4 パーセンタイル:19.55(Chemistry, Multidisciplinary)

Extractants impregnated onto porous materials exhibit high performance in adsorption kinetics of metal ions because metal ions are transported by the permeative flow of a metal solution through pores. A simple scheme for the stable impregnation of extractants is necessary to extend the application of extractants. Aliquat 336 was impregnated onto a porous sheet on the basis of the hydrophobic and electrostatic interactions between the octyl group of Aliquat 336 and the undecanoicacid-group-containing polymer chain grafted onto the porous sheet. Palladium chloride solution was fed to the bed charged with the Aliquat 336-impregnated porous sheet, driven by a pressure difference. The dynamic binding capacity of the Aliquat 336-impregnated porous sheet was 0.60 mmol/g, which was one or two orders of magnitude higher than the space velocities of conventional Aliquat 336-impregnated beads.



菖蒲 信博; 加藤 昌俊*; 高尾 朋枝*; 寺島 大輔*; 田中 良枝*; 白須 桐紀*; 天澤 弘也; 鯉渕 浩人; 仲田 久和

JAEA-Review 2013-028, 175 Pages, 2013/12




幌延深地層研究計画; 平成23年度調査研究成果報告

中山 雅; 天野 健治; 常盤 哲也; 山本 陽一; 大山 卓也; 天野 由記; 村上 裕晃; 稲垣 大介; 津坂 仁和; 近藤 桂二; et al.

JAEA-Review 2012-035, 63 Pages, 2012/09




Tolerance of anhydrobiotic eggs of the tardigrade ${it Ramazzottius varieornatus}$ to extreme environments

堀川 大樹*; 山口 理美*; 坂下 哲哉; 田中 大介*; 浜田 信行*; 行弘 文子*; 桑原 宏和*; 國枝 武和*; 渡邊 匡彦*; 中原 雄一*; et al.

Astrobiology, 12(4), p.283 - 289, 2012/04

 被引用回数:20 パーセンタイル:70.08(Astronomy & Astrophysics)

クマムシの乾燥休眠状態である卵の孵化率について、宇宙空間の特徴的な極限環境要因である放射線(Heイオン線),極低温,高真空に対する耐性を調べた。その結果、50%が孵化できない線量が約500Gy, -196度に曝されても70%以上が孵化し、6$$times$$10$$^{-5}$$Paの高真空においた後でも孵化することができることがわかった。以上の結果から、宇宙空間であってもクマムシの耐性能力により、乾眠状態であるならば、存在できる可能性が示唆された。


Synthesis, structural transformation, thermal stability, valence state, and magnetic and electronic properties of PbNiO$$_{3}$$ with perovskite- and LiNbO$$_{3}$$-type structures

稲熊 宜之*; 田中 樹恵*; 土谷 武史*; 森 大輔*; 勝又 哲裕*; 大場 友則*; 開 康一*; 高橋 利宏*; 齋藤 寛之

Journal of the American Chemical Society, 133(42), p.16920 - 16929, 2011/09

 被引用回数:75 パーセンタイル:86.04(Chemistry, Multidisciplinary)

We synthesized two high-pressure polymorphs PbNiO$$_{3}$$ with different structures, a perovskite-type and a LiNbO$$_{3}$$-type structure, and investigated their formation behavior, detailed structure, structural transformation, thermal stability, valence state of cations, and magnetic and electronic properties. A perovskite-type PbNiO$$_{3}$$ synthesized at 800$$^{circ}$$C under a pressure of 3 GPa crystallizes as an orthorhombic GdFeO$$_{3}$$-type structure with a space group Pnma. The reaction under high pressure was monitored by an in situ energy dispersive X-ray diffraction experiment, which revealed that a perovskit-type phase was formed even at 400$$^{circ}$$C under 3 GPa.


Azimuthal correlations of electrons from heavy-flavor decay with hadrons in $$p+p$$ and Au+Au collisions at $$sqrt{s_{NN}}$$ = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; 秋葉 康之*; Al-Bataineh, H.*; Alexander, J.*; 青木 和也*; Aphecetche, L.*; Aramaki, Y.*; et al.

Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04

 被引用回数:8 パーセンタイル:52.71(Physics, Nuclear)




坂口 忍; 立花 郁也; 越野 克彦; 白水 秀知; 白井 更知; 今本 信雄; 冨田 恒夫; 飛田 祐夫; 山中 淳至; 小林 大輔; et al.

JAEA-Technology 2011-006, 24 Pages, 2011/03



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