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Practical tests of neutron transmission imaging with a superconducting kinetic-inductance sensor

Vu, TheDang; 宍戸 寛明*; 相澤 一也; 小嶋 健児*; 小山 富男*; 及川 健一; 原田 正英; 奥 隆之; 曽山 和彦; 宮嶋 茂之*; et al.

Nuclear Instruments and Methods in Physics Research A, 1006, p.165411_1 - 165411_8, 2021/08

 被引用回数:0 パーセンタイル:0.03(Instruments & Instrumentation)

We found that the sizes of the Gd islands determined from the transmission image correlated strongly with those determined from the SEM image. We demonstrated the CB-KID could be used to identify (1) tiny voids in a thermally sprayed continuous Gd$$_2$$O$$_3$$ film in and (2) various mosaic morphologies and different eutectic microstructures in Wood's metal samples. The fact that the CB-KID system could be used to identify features of samples with a wide distribution of sizes and thicknesses is promising for real application of the device for imaging samples of interest to material scientists. Operating the CB-KID at higher temperatures appreciably improved the efficiency for simultaneously identifying the X and Y positions of hotspots. We also compared the detection efficiency with the PHITS simulations. We now plan to improve the detection efficiency by increasing the thickness of the $$^{10}$$B neutron conversion layer



榊原 博; 青木 伸廣; 武藤 雅祐; 小田部 隼; 高橋 謙二*; 藤田 直幸*; 檜山 和彦*; 鈴木 宏和*; 鴨川 敏幸*; 横須賀 徹*; et al.

JAEA-Technology 2020-020, 73 Pages, 2021/03




Homogeneity of neutron transmission imaging over a large sensitive area with a four-channel superconducting detector

Vu, TheDang; 宍戸 寛明*; 小嶋 健児*; 小山 富男*; 及川 健一; 原田 正英; 宮嶋 茂之*; 奥 隆之; 曽山 和彦; 相澤 一也; et al.

Superconductor Science and Technology, 34(1), p.015010_1 - 015010_10, 2021/01

 被引用回数:2 パーセンタイル:72.02(Physics, Applied)

We demonstrated that a four-readout superconducting neutron imaging system shows good spatial heterogeneity and linearity using the delay-line method. We examined the precise pattern of a $$^{10}$$B-dot-array absorber and found the X-direction pitch (Px) = 250.7 um with a scatter of (Hx)= 5.4 um and the Y-direction pitch (Py)= 249.1 um with a scatter of (Hy)= 3.4 um while the $$^{10}$$B dot array was fully extended toward the X direction across the detector sensitive area. We consider that this demonstrates detection with good spatial homogeneity and conclude. The transmission-imaging system is suitable for use at pulsed neutron facilities. We also reported a clear transmission image of tiny screws and nuts, and ladybug (insect). We recognize that further efforts to improve the detection efficiency are necessary to make using the detector more practical.


Numerical simulation of the solid particle sedimentation and bed formation behaviors using a hybrid method

Sheikh, M. A. R.*; Liu, X.*; 松元 達也*; 守田 幸路*; Guo, L.*; 鈴木 徹*; 神山 健司

Energies (Internet), 13(19), p.5018_1 - 5018_15, 2020/10

 被引用回数:0 パーセンタイル:0(Energy & Fuels)

In the safety analysis of sodium-cooled fast reactors, numerical simulations of various thermal-hydraulic phenomena with multicomponent and multiphase flows in core disruptive accidents (CDAs) are regarded as particularly difficult. In the material relocation phase of CDAs, core debris settle down on a core support structure and/or an in-vessel retention device and form a debris bed. The bed's shape is crucial for the subsequent relocation of the molten core and heat removal capability as well as re-criticality. In this study, a hybrid numerical simulation method, coupling the multi-fluid model of the three-dimensional fast reactor safety analysis code SIMMER-IV with the discrete element method (DEM), was applied to analyze the sedimentation and bed formation behaviors of core debris. Three-dimensional simulations were performed and compared with results obtained in a series of particle sedimentation experiments. The present simulation predicts the sedimentation behavior of mixed particles with different properties as well as homogeneous particles. The simulation results on bed shapes and particle distribution in the bed agree well with experimental measurements. They demonstrate the practicality of the present hybrid method to solid particle sedimentation and bed formation behaviors of mixed as well as homogeneous particles.


Development and application of a $$^3$$He neutron spin filter at J-PARC

奥平 琢也; 奥 隆之; 猪野 隆*; 林田 洋寿*; 吉良 弘*; 酒井 健二; 廣井 孝介; 高橋 慎吾*; 相澤 一也; 遠藤 仁*; et al.

Nuclear Instruments and Methods in Physics Research A, 977, p.164301_1 - 164301_8, 2020/10

 被引用回数:4 パーセンタイル:76.41(Instruments & Instrumentation)

We are developing a neutron polarizer with polarized $$^3$$He gas, referred to as a $$^3$$He spin filter, based on the Spin Exchange Optical Pumping (SEOP) for polarized neutron scattering experiments at Materials and Life Science Experimental Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC). A $$^3$$He gas-filling station was constructed at J-PARC, and several $$^3$$He cells with long spin relaxation times have been fabricated using the gas-filling station. A laboratory has been prepared in the MLF beam hall for polarizing $$^3$$He cells, and compact pumping systems with laser powers of 30 W and 110 W, which can be installed onto a neutron beamline, have been developed. A $$^3$$He polarization of 85% was achieved at a neutron beamline by using the pumping system with the 110 W laser. Recently, the first user experiment utilizing the $$^3$$He spin filter was conducted, and there have been several more since then. The development and utilization of $$^3$$He spin filters at MLF of J-PARC are reported.


Double-exposure method with synchrotron white X-ray for stress evaluation of coarse-grain materials

鈴木 賢治*; 城 鮎美*; 豊川 秀訓*; 佐治 超爾*; 菖蒲 敬久

Quantum Beam Science (Internet), 4(3), p.25_1 - 25_14, 2020/09



Effects of diluents on the separation of minor actinides from lanthanides with tetradodecyl-1,10-phenanthroline-2,9-diamide from nitric acid medium

筒井 菜緒; 伴 康俊; 鈴木 英哉*; 中瀬 正彦*; 伊藤 紗弓*; 稲葉 優介*; 松村 達郎; 竹下 健二*

Analytical Sciences, 36(2), p.241 - 246, 2020/02

 被引用回数:5 パーセンタイル:41.67(Chemistry, Analytical)

ランタノイドからのアクチノイドの効果的な分離について調べるため、新規抽出剤テトラドデシル-1,10-フェナントロリン-2,9-ジアミド(TDdPTDA)と3-ニトロベンゾトリフルオリド(F-3),ニトロベンゼン, ${it n}$-ドデカンなど様々な希釈剤並びにAm, Cm及びLnを用いて単段のバッチ試験を行った。抽出速度は実際の抽出フローシートを実行するにあたり十分な速さであった。分配比対TDdPTDA濃度及び分配比対硝酸濃度のグラフの傾きは、F-3系及びニトロベンゼン系では似ていたが、${it n}$-ドデカン系とは異なっていた。これらの違いは希釈剤の特徴によるものである。この研究ではTDdPTDAが高い${it D}$ $$_{Am}$$及び${it D}$ $$_{Cm}$$を示し、AmのLnに対する分離係数(${it SF}$)は分離するのに十分な値であることを明らかにした。



鈴木 賢治*; 菖蒲 敬久; 城 鮎美*

材料, 68(4), p.312 - 317, 2019/04



Intergranular strains of plastically deformed austenitic stainless steel

鈴木 賢治*; 菖蒲 敬久

E-Journal of Advanced Maintenance (Internet), 10(4), p.9 - 17, 2019/02



Observation of a Be double-Lambda hypernucleus in the J-PARC E07 experiment

江川 弘行; 足利 沙希子; 長谷川 勝一; 橋本 直; 早川 修平; 細見 健二; 市川 裕大; 今井 憲一; 金原 慎二*; 七村 拓野; et al.

Progress of Theoretical and Experimental Physics (Internet), 2019(2), p.021D02_1 - 021D02_11, 2019/02

 被引用回数:13 パーセンタイル:85.21(Physics, Multidisciplinary)

A double-$$Lambda$$ hypernucleus, $${}_{LambdaLambda}mathrm{Be}$$, was observed by the J-PARC E07 collaborationin nuclear emulsions tagged by the $$(K^{-},K^{+})$$ reaction. This event was interpreted as a production and decay of $$ {}_{LambdaLambda}^{;10}mathrm{Be}$$,$${}_{LambdaLambda}^{;11}mathrm{Be}$$, or $${}_{LambdaLambda}^{;12}mathrm{Be}^{*}$$ via $$Xi^{-}$$ capture in $${}^{16}mathrm{O}$$.By assuming the capture in the atomic 3D state, the binding energy of two $$Lambda$$ hyperons$$,$$($$B_{LambdaLambda}$$)of these double-$$Lambda$$ hypernuclei are obtained to be$$15.05 pm 0.11,mathrm{MeV}$$, $$19.07 pm 0.11,mathrm{MeV}$$, and $$13.68 pm 0.11,mathrm{MeV}$$, respectively. Based on the kinematic fitting, $${}_{LambdaLambda}^{;11}mathrm{Be}$$ is the most likely explanation for the observed event.


Al-impurity-induced magnetic excitations in heavily over-doped La$$_{1.7}$$Sr$$_{0.3}$$Cu$$_{0.95}$$Al$$_{0.05}$$O$$_{4}$$

池内 和彦*; 中島 健次; 河村 聖子; 梶本 亮一; 脇本 秀一; 鈴木 謙介*; 藤田 全基*

AIP Advances (Internet), 8(10), p.101318_1 - 101318_5, 2018/10

 被引用回数:0 パーセンタイル:0(Nanoscience & Nanotechnology)



Prediction of the drying behavior of debris in Fukushima Daiichi Nuclear Power Station for dry storage

仲吉 彬; 鈴木 誠矢; 岡村 信生; 渡部 雅之; 小泉 健治

Journal of Nuclear Science and Technology, 55(10), p.1119 - 1129, 2018/10

 被引用回数:1 パーセンタイル:17.98(Nuclear Science & Technology)

Treatment policies for debris from Fukushima Daiichi Nuclear Power Station is not decided, however, any policies may include medium and long term storages of debris. Dry storages may be desirable in terms of costs and handlings, but it is necessary to assess generating hydrogen during storages due to radiolysis of accompanied water with debris before debris storages. Al$$_{2}$$O$$_{3}$$, SiO$$_{2}$$, ZrO$$_{2}$$, UO$$_{2}$$ and cement paste pellets as simulated debris were prepared, which have various porosities and pore size distribution. Weight changes of wet samples were measured at various drying temperatures (100, 200, 300, and 1000$$^{circ}$$C) using a Thermogravimetry, under helium gas flow (50 cc/min) or reduced pressure conditions (reducing pressure rate: 200 Pa in 30 min). From the results, drying curves were evaluated. There is a possibility that cold ceramics can predict drying behaviors of ceramics debris as a simulation because all of the ceramics pellets generally showed similar drying characteristics in this experiment. The cement paste pellets indicated different behavior compared to the ceramics pellets, and the drying time of the cement paste pellets was longer even in 1000$$^{circ}$$C conditions. It is necessary to decide the standard level of the dry state for a drying MCCI products which may be accompanied by concrete.


Ce substitution and reduction annealing effects on electronic states in Pr$$_{2-x}$$Ce$$_x$$CuO$$_4$$ studied by Cu $$K$$-edge X-ray absorption spectroscopy

浅野 駿*; 石井 賢司*; 松村 大樹; 辻 卓也; 伊奈 稔哲*; 鈴木 謙介*; 藤田 全基*

Journal of the Physical Society of Japan, 87(9), p.094710_1 - 094710_5, 2018/09

 被引用回数:7 パーセンタイル:63.33(Physics, Multidisciplinary)

We investigated the Ce substitution and reduction annealing effects on the electronic states at copper sites by Cu $$K$$-edge X-ray absorption near-edge structure measurements in Pr$$_{2-x}$$Ce$$_x$$CuO$$_{4+alpha-delta}$$ (PCCO) with varying $$x$$ and $$delta$$ (amount of oxygen loss during annealing). Absorption near-edge spectra were modified by Ce substitution and reduction annealing similarly with increasing $$x$$ and $$delta$$. Considering electron doping by Ce substitution, this similarity indicates an increase in electron number at the copper sites due to annealing ($$n_{AN}$$). Furthermore, quantitative analyses of the spectra clarified that the number of Cu$$^+$$ sites, corresponding to the induced electron number by Ce substitution increases linearly with $$x$$ in the as-sintered PCCO, whereas $$n_{AN}$$ is not exactly equal to 2$$delta$$. For each $$x$$-fixed sample, $$n_{AN}$$tends to exceed 2$$delta$$ with increasing $$delta$$, suggesting the emergence of two types of carrier due to annealing.


Sedimentation behavior of mixed solid particles

Sheikh, Md. A. R.*; Son, E.*; 神山 基紀*; 森岡 徹*; 松元 達也*; 守田 幸路*; 松場 賢一; 神山 健司; 鈴木 徹*

Journal of Nuclear Science and Technology, 55(6), p.623 - 633, 2018/06

 被引用回数:5 パーセンタイル:64.98(Nuclear Science & Technology)



Charmonium ground and excited states at finite temperature from complex Borel sum rules

荒木 賢志*; 鈴木 渓*; Gubler, P.; 岡 眞

Physics Letters B, 780, p.48 - 53, 2018/05


 被引用回数:3 パーセンタイル:40.34(Astronomy & Astrophysics)




鈴木 裕士; 楠 浩一*; 佐竹 高祐*; 兼松 学*; 小山 拓*; 丹羽 章暢*; 椛山 健二*; 向井 智久*; 川崎 卓郎; Harjo, S.

非破壊検査, 67(4), p.180 - 186, 2018/04



Reduction and oxidation annealing effects on Cu $$K$$-edge XAFS for electron-doped cuprate superconductors

浅野 駿*; 鈴木 謙介*; 松村 大樹; 石井 賢司*; 伊奈 稔哲*; 藤田 全基*

Journal of Physics; Conference Series, 969, p.012051_1 - 012051_5, 2018/04

 被引用回数:2 パーセンタイル:83.27

Reduction and oxidation annealing effects on the electronic states around the copper sites for Pr$$_{2-x}$$Ce$$_x$$CuO$$_4$$ and Nd$$_{2-x}$$Ce$$_x$$CuO$$_4$$ with $$x$$ = 0 and $$x$$ = 0.15 were investigated by Cu $$K$$-edge X-ray absorption measurements. Cu $$K$$ near-edge spectra were changed by the reduction annealing in a manner similar to the case of Ce substitution for both $$x$$ = 0 and $$x$$ = 0.15. This means an increase of electron density at the copper sites, indicating the aspect of electron doping in the reduction annealing. This reduction annealing effect on the near-edge spectra are reverted by the additional oxidation annealing. The amount of electron density around the copper sites is varied by the reduction and oxidation annealing, reversibly, corresponding to the reversible variation of the physical property from insulating to superconductivity.


Chemical form analysis of reaction products in Cs-adsorption on stainless steel by means of HAXPES and SEM/EDX

小畠 雅明; 岡根 哲夫; 中島 邦久; 鈴木 恵理子; 大和田 謙二; 小林 啓介*; 山上 浩志; 逢坂 正彦

Journal of Nuclear Materials, 498, p.387 - 394, 2018/01

 被引用回数:9 パーセンタイル:81.13(Materials Science, Multidisciplinary)



Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex, 2; Neutron scattering instruments

中島 健次; 川北 至信; 伊藤 晋一*; 阿部 淳*; 相澤 一也; 青木 裕之; 遠藤 仁*; 藤田 全基*; 舟越 賢一*; Gong, W.*; et al.

Quantum Beam Science (Internet), 1(3), p.9_1 - 9_59, 2017/12



Investigation of main radiation source above shield plug of Unit 3 at Fukushima Daiichi Nuclear Power Station

平山 英夫*; 近藤 健次郎*; 鈴木 征四郎*; 谷村 嘉彦; 岩永 宏平*; 永田 寛*

EPJ Web of Conferences, 153, p.08010_1 - 08010_3, 2017/09

 被引用回数:0 パーセンタイル:0.03

福島第一原子力発電所3号機のシールドプラグ上は高線量率となっており、この主要な線源を調査するために鉛製コリメータ付CdZnTe検出器を用いて光子線の波高分布を測定した。その結果、低エネルギー光子線の寄与が大きいことがわかった。0.662MeV光子のピーク計数率から、60cm厚コンクリート製のシールドプラグ1層目下部のCs-137放射能密度は、8.1$$times$$10$$^9$$ $$sim$$ 5.7$$times$$10$$^{10}$$Bq/cm$$^2$$であると評価された。Cs-137が、半径6mのシールドプラグの下部隙間に、シールドプラグ上5箇所で評価した放射能密度の平均値2.6$$times$$10$$^{10}$$Bq/cm$$^2$$で均一に付着しているとすると、Cs-137の合計放射能は30PBqと見積もられる。

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