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Oxidative decomposition of ammonium ion with ozone in the presence of cobalt and chloride ions for the treatment of radioactive liquid waste

粟飯原 はるか; 渡部 創; 柴田 淳広; Mahardiani, L.*; 大友 亮一*; 神谷 裕一*

Progress in Nuclear Energy, 139, p.103872_1 - 103872_9, 2021/09

 被引用回数:1 パーセンタイル:32.89(Nuclear Science & Technology)

To prevent unexpected accidents at nuclear facilities caused by accumulated ammonium nitrate in an aqueous liquid waste containing ammonium salts and nitric acid, NH $$_{4}$$ $$^{+}$$ in the liquid waste must be decomposed under mild reaction conditions. In this study, we investigated the oxidative decomposition of NH $$_{4}$$ $$^{+}$$ with O$$_{3}$$ at 333 K in the presence of a homogeneous Co$$^{2+}$$ catalyst and Cl$$^{-}$$ in the wide pH range of the test solution. The reaction behavior was greatly affected by pH of the test solution. In a basic solution at pH 12, high conversion of NH $$_{4}$$ $$^{+}$$ was obtained even in the absence of Co$$^{2+}$$ and Cl$$^{-}$$ and the main product was NO $$_{3}$$$$^{-}$$. However, Co$$^{2+}$$ and Cl$$^{-}$$ in the solution greatly enhanced the decomposition rate of NH $$_{4}$$ $$^{+}$$ in acidic to mild basic solutions (pH 1-8), while only low conversion of NH $$_{4}$$ $$^{+}$$ was observed unless both Co$$_{2+}$$ and Cl$$^{-}$$ were present. For the reaction with Co$$^{2+}$$ and Cl$$^{-}$$ in the solutions, NH$$_{4}$$ $$^{+}$$ was transformed mainly into chloramines (NH $$_{x}$$Cl $$_{3-x}$$, x = 1-3) by the reaction with HClO, which was formed by the reaction of Cl$$^{-}$$ with O$$_{3}$$ catalyzed by the homogeneous Co$$^{2+}$$ catalyst, and led to the high decomposition rate of NH$$_{4}$$ $$^{+}$$. Cl$$^{-}$$ suppressed the formation of the precipitate CoO(OH) during the reaction and consequently the Co$$^{2+}$$ catalyst stably existed in the reaction solution, which was another reason for the high decomposition rate of NH$$_{4}$$ $$^{+}$$ in the presence of Cl$$^{-}$$. Owing to the swift decomposition of NH$$_{4}$$ $$^{+}$$ under mild reaction conditions and small formation of secondary waste, the oxidative decomposition of NH$$_{4}$$ $$^{+}$$ in the presence of the homogeneous Co$$^{2+}$$ catalyst and Cl$$^{-}$$ is suitable and applicable for the treatment of the aqueous liquid waste containing ammonium salts and nitric acid.


High-spin states in $$^{35}$$S

郷 慎太郎*; 井手口 栄治*; 横山 輪*; 青井 考*; Azaiez, F.*; 古高 和禎; 初川 雄一; 木村 敦; 木佐森 慶一*; 小林 幹*; et al.

Physical Review C, 103(3), p.034327_1 - 034327_8, 2021/03

 被引用回数:4 パーセンタイル:58.42(Physics, Nuclear)

Excited states in $$^{35}$$S were investigated by in-beam $$gamma$$-ray spectroscopy using the $$^{26}$$Mg($$^{18}$$O, 2$$alpha$$1$$n$$) fusion-evaporation reaction. The de-exciting $$gamma$$-rays were measured with germanium detector arrays along with the measurement of evaporated charged particles in a $$4pi$$ segmented Si detector array. The level scheme was extended up to 12470 keV. The obtained level structure is compared with the large-scale shell-model calculations. The possibility of isoscalar-pair excited states is discussed for $$J=(17/2)$$ states with comparison between the experimental and theoretical results.


Upgrade of the 3-MeV linac for testing of accelerator components at J-PARC

近藤 恭弘; 平野 耕一郎; 伊藤 崇; 菊澤 信宏; 北村 遼; 森下 卓俊; 小栗 英知; 大越 清紀; 篠崎 信一; 神藤 勝啓; et al.

Journal of Physics; Conference Series, 1350, p.012077_1 - 012077_7, 2019/12

 被引用回数:1 パーセンタイル:52.4

J-PARC加速器の要素技術試験に必要な3MeV H$$^{-}$$リニアックを高度化した。イオン源にはJ-PARCリニアックと同じものを用い、RFQは、J-PARCリニアックで2014年まで使用した30mA RFQに代わり新たに製作した50mA RFQを設置した。したがって、このシステムはエネルギー3MeV、ビーム電流50mAとなる。このリニアックの本来の目的は、このRFQの試験であるが、J-PARC加速器の運転維持に必要な様々な機器の試験を行うことができる。加速器は既に試運転が終了しており、測定プログラムが開始されつつある。この論文では、この3MeV加速器の現状について報告する。


STRAD project for systematic treatments of radioactive liquid wastes generated in nuclear facilities

渡部 創; 小木 浩通*; 荒井 陽一; 粟飯原 はるか; 高畠 容子; 柴田 淳広; 野村 和則; 神谷 裕一*; 浅沼 徳子*; 松浦 治明*; et al.

Progress in Nuclear Energy, 117, p.103090_1 - 103090_8, 2019/11


 被引用回数:9 パーセンタイル:78.07(Nuclear Science & Technology)

A new collaborative research project for systematic treatments of radioactive liquid wastes containing various reagents generating in nuclear facilities was started from 2018 initiated by Japan Atomic Energy Agency. The project was named as STRAD (Systematic Treatments of RAdioactive liquid wastes for Decommissioning) project. Tentative targets to be studied under the project are aqueous and organic liquid wastes which have been generated by experiments and analyses in a reprocessing experimental laboratory of JAEA. Currently fundamental studies for treatments of the liquid wastes with complicated compositions are underway. In the STRAD project, process flow for treatment of ammonium ion involved in aqueous waste was designed though the inactive experiments, and decomposition of ammonium ion using catalysis will be carried out soon. Adsorbents for recovery of U and Pu from spent solvent were also developed. Demonstration experiments on genuine spent solvent is under planning.



佐々木 宏和*; 西久保 英郎*; 西田 真輔*; 山崎 悟志*; 中崎 竜介*; 磯松 岳己*; 湊 龍一郎*; 衣川 耕平*; 今村 明博*; 大友 晋哉*; et al.

古河電工時報, (138), p.2 - 10, 2019/02



Atmospheric modeling of $$^{137}$$Cs plumes from the Fukushima Daiichi Nuclear Power Plant; Evaluation of the model intercomparison data of the Science Council of Japan

北山 響*; 森野 悠*; 滝川 雅之*; 中島 映至*; 速水 洋*; 永井 晴康; 寺田 宏明; 斉藤 和雄*; 新堀 敏基*; 梶野 瑞王*; et al.

Journal of Geophysical Research; Atmospheres, 123(14), p.7754 - 7770, 2018/07

 被引用回数:24 パーセンタイル:70.42(Meteorology & Atmospheric Sciences)



Am, Cm recovery from genuine HLLW by extraction chromatography

渡部 創; 佐野 雄一; 小藤 博英; 竹内 正行; 柴田 淳広; 野村 和則

Journal of Radioanalytical and Nuclear Chemistry, 316(3), p.1113 - 1117, 2018/06

 被引用回数:8 パーセンタイル:63.44(Chemistry, Analytical)

Am(III) and Cm(III) recovery experiments with the extraction chromatography technology were carried out on genuine HLLW obtained by reprocessing of the Fast Reactor fuel. Modification of the flow-sheet with 2 steps column operations using CMPO/SiO$$_{2}$$-P and HDEHP/SiO$$_{2}$$-P adsorbents achieved more than 90% recovery yields for Am(III) and Cm(III) with decontamination factor of 1000 for Eu(III). This is a significant progress in development of the technology for the implementation.


Neutron scattering study of yttrium iron garnet

社本 真一; 伊藤 孝; 大西 弘明; 山内 宏樹; 稲村 泰弘; 松浦 直人*; 赤津 光洋*; 樹神 克明; 中尾 朗子*; 茂吉 武人*; et al.

Physical Review B, 97(5), p.054429_1 - 054429_9, 2018/02

 被引用回数:16 パーセンタイル:66.02(Materials Science, Multidisciplinary)



Flow-sheet study of MA recovery by extraction chromatography for SmART cycle project

渡部 創; 野村 和則; 北脇 慎一; 柴田 淳広; 小藤 博英; 佐野 雄一; 竹内 正行

Procedia Chemistry, 21, p.101 - 108, 2016/12


 被引用回数:11 パーセンタイル:99.2

Optimization in a flow-sheet of the extraction chromatography process for minor actinides (MA(III); Am and Cm) recovery from high level liquid waste (HLLW) were carried out through batch-wise adsorption/elution experiments on diluted HLLW and column separation experiments on genuine HLLW. Separation experiments using CMPO/SiO$$_{2}$$-P and HDEHP/SiO$$_{2}$$-P adsorbent columns with an improved flow-sheet successfully achieved more than 70 % recovery yields of MA(III) with decontamination factors of Ln(III) $$>$$ 10$$^{3}$$, and a modified flow-sheet for less contamination with fission products was proposed consequently. These results will contribute to MA(III) recovery operations for SmART Cycle project in Japan Atomic Energy Agency which is planned to demonstrates FR fuel cycle with more than 1g of Am.


Recovery of radiation degradation on inverted metamorphic triple-junction solar cells by light soaking

柴田 優一*; 今泉 充*; 佐藤 真一郎; 大島 武; 大岡 幸代*; 高本 達也*

Proceedings of 11th International Workshop on Radiation Effects on Semiconductor Devices for Space Applications (RASEDA-11) (Internet), p.65 - 68, 2015/11

次期の高効率薄膜宇宙用太陽電池として逆積み格子不整合型(IMM)三接合太陽電池の開発が進められている。最近、IMM三接合太陽電池に関して、放射線により劣化した特性が光照射により回復する現象が見いだされたが、その詳細は明らかになっていない。そこで、1MeV電子線を3$$times$$10$$^{15}$$ e$$^-$$/cm$$^2$$照射することで劣化させたIMM三接合太陽電池の光照射回復現象を調べた。その結果、3時間の光照射(AM0、1sun)によって開放電圧が43mV回復することが判明した。また、太陽電池中に残留する欠陥について調べるためにエレクトロルミネセンス測定したところ、InGaP, GaAs, InGaAsの三層のうち、InGaPトップセルのエレクトロルミネセンス強度が光照射後に増加していることがわかった。このことから、光照射による回復は、InGaPトップセル中の欠陥が回復したことに起因することが明らかとなった。


Superdeformation in $$^{35}$$S

郷 慎太郎*; 井手口 栄治*; 横山 輪*; 小林 幹*; 木佐森 慶一*; 高木 基伸*; 宮 裕之*; 大田 晋輔*; 道正 新一郎*; 下浦 享*; et al.

JPS Conference Proceedings (Internet), 6, p.030005_1 - 030005_4, 2015/06

The high-spin states in $$^{35}$$S were investigated at Tandem-ALTO facility in Institut de Physique Nucl$'e$aire d'Orsay The $$^{26}$$Mg($$^{18}$$O, 2$$alpha$$1n)$$^{35}$$S fusion evaporation reaction was used to populate high-spin states in $$^{35}$$S. The germanium $$gamma$$-ray detector array ORGAM was employed to measure $$gamma$$ rays from high-spin states and charged particles evaporated from the compound nuclei were detected by a segmented silicon detector, Si-Ball. A level scheme for $$^{35}$$S was deduced based on the gamma-gamma-coincidence analysis and $$gamma$$-ray angular correlation analysis. The half-life of the transition in the superdeformed band was estimated by measuring the residual Doppler shift. The deduced half-life shows the large collectivity of the band.


Detailed deposition density maps constructed by large-scale soil sampling for $$gamma$$-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant accident

斎藤 公明; 谷畑 勇夫*; 藤原 守; 齊藤 敬*; 下浦 享*; 大塚 孝治*; 恩田 裕一*; 星 正治*; 池内 嘉宏*; 高橋 史明; et al.

Journal of Environmental Radioactivity, 139, p.308 - 319, 2015/01

 被引用回数:216 パーセンタイル:98.81(Environmental Sciences)

The soil deposition density maps of $$gamma$$-ray emitting radioactive nuclides from the Fukushima Daiichi Nuclear Power Plant (NPP) accident were constructed on the basis of the results from large-scale soil sampling. The 10,915 soil samples were collected at 2,168 locations. $$gamma$$-rays emitted from the samples were measured by Ge detectors and analyzed using a reliable unified method. The determined radioactivity was corrected to that as of June 14, 2011 by taking into account the intrinsic decay constant of each nuclide. Finally the maps were created for $$^{134}$$Cs, $$^{137}$$Cs, $$^{131}$$I, $$^{rm 129m}$$Te and $$^{rm 110m}$$Ag. The radioactivity ratio of $$^{134}$$Cs to $$^{137}$$Cs was almost constant as 0.91 irrelevant to the soil sampling location. Effective doses for 50 years after the accident were evaluated for external and inhalation exposures due to the observed radioactive nuclides. The radiation doses from radioactive cesium were found to be much higher than those from other radioactive nuclides.


Transmission properties of C$$_{60}$$ ions through micro- and nano-capillaries

土田 秀次*; 間嶋 拓也*; 冨田 成夫*; 笹 公和*; 鳴海 一雅; 齋藤 勇一; 千葉 敦也; 山田 圭介; 平田 浩一*; 柴田 裕実*; et al.

Nuclear Instruments and Methods in Physics Research B, 315, p.336 - 340, 2013/11

 被引用回数:3 パーセンタイル:26.8(Instruments & Instrumentation)

Applying the beam-focusing method with capillaries to C$$_{60}$$ projectiles in the velocity range between 0.14 and 0.2 a.u., transmission properties of C$$_{60}$$ ions through two different types of capillaries are studied: (1) a borosilicate-glass single microcapillary with an outlet diameter of 5.5 $$mu$$m, and (2) an Al$$_{2}$$O$$_{3}$$ multicapillary foil with approximatey 70-nm pores in diameter and a high aspect ratio of approximately 750. Transmitted-particle compositions are measured with the electrostatic-deflection method combined with a two-dimensional position-sensitive detector. In the experiments with the single microcapillary, the main transmitted component is found to be primary C$$_{60}$$ ions, which are focused in the area equal to the capillary outlet diameter. The other components are charge-exchanged C$$_{60}$$ ions and charged or neutral fragments (fullerene-like C$$_{60-2m}$$ and small C$$_{n}$$ particles), and their fractions decrease with decreasing projectile velocity. Similar results are obtained in the experiments with the multicapillary foil. It is concluded from the relative transimission fractions of more than 80% that the C$$_{60}$$ transmission fraction is considerably high for both types of the capillaries in the present velocity range.


Visualization of $$gamma$$H2AX foci caused by heavy ion particle traversal; Distribution between core track versus non-track damage

中島 菜花子*; Brunton, H.*; 渡辺 立子; Shrikhande, A.*; 平山 亮一*; 松藤 成弘*; 藤森 亮*; 村上 健*; 岡安 隆一*; Jeggo, P.*; et al.

PLOS ONE (Internet), 8(8), p.e70107_1 - e70107_14, 2013/08

 被引用回数:62 パーセンタイル:91.13(Multidisciplinary Sciences)



Dissolution behavior of irradiated mixed oxide fuel with short stroke shearing for fast reactor reprocessing

池内 宏知; 佐野 雄一; 柴田 淳広; 小泉 務; 鷲谷 忠博

Journal of Nuclear Science and Technology, 50(2), p.169 - 180, 2013/02

 被引用回数:6 パーセンタイル:49.41(Nuclear Science & Technology)



Ion induced luminescence from sapphire irradiated with swift cluster ion beams; Cluster ion size and energy dependences

柴田 裕実*; 齋藤 勇一; 千葉 敦也; 山田 圭介; 鳴海 一雅; 田口 光正

JAEA-Review 2012-046, JAEA Takasaki Annual Report 2011, P. 162, 2013/01

This study is to elucidate the characteristics of the interaction between energetic cluster ions and solids by means of measuring luminescence from solid surfaces irradiated with cluster ions. We report present results of luminescence measurement for the sapphire target irradiated with carbon cluster ions. Luminescent spectra from sapphire induced by 0.25-3.0 MeV/atom (21-252 keV/u) C$$_{1}$$$$^{+}$$-C$$_{8}$$$$^{+}$$ ion irradiation were measured in the wavelength range of 250-800 nm as a function of ion fluence at room temperature. The experimental results show the same tendency as a calculation of stopping power theory. This suggests that luminescence caused by irradiation defects directly relates to the stopping power of incident cluster ion.


Ground-state configuration of the $$N=157$$ nucleus $$^{259}$$No

浅井 雅人; 塚田 和明; 阪間 稔*; 羽場 宏光*; 市川 隆敏*; 石井 康雄; 豊嶋 厚史; 石井 哲朗; 西中 一朗; 永目 諭一郎; et al.

Physical Review C, 87(1), p.014332_1 - 014332_6, 2013/01

 被引用回数:6 パーセンタイル:43.85(Physics, Nuclear)



Ion induced luminescence from sapphire irradiated with swift cluster ion beams; Energy dependence of incident cluster beams

柴田 裕実*; 齋藤 勇一; 千葉 敦也; 山田 圭介; 田口 光正; 鳴海 一雅

JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 152, 2012/01

Luminescent spectra from sapphire ($$alpha$$-Al$$_2$$O$$_3$$) induced by 0.5$$sim$$1.5 MeV/atom (42$$sim$$126 keV/u) C$$_1$$$$sim$$C$$_8$$ ion irradiation were measured in the wavelength range of 250-800 nm as a function of ion fluence at room temperature. As a result, the luminescence yields increase as the cluster sizes increase for every incident energy range, but the ratios R$$_n$$ (R$$_n$$ = I(n) /nI(1), where n is number of cluster ion, I(n) is the yield for C$$_n$$$$^+$$ cluster ion and I(1) is the yield for C$$_1$$$$^+$$ ion) become less than unity in the energy range of 0.5 and 1.0 MeV/atom. The experimental results show the same tendency as the calculation of stopping power theory and exist between unity and the value for the united atom of the cluster ion. This suggests that luminescence caused by irradiation defects directly relates the stopping power of incident cluster ion.


Dissolution behavior of irradiated mixed-oxide fuels with different plutonium contents

池内 宏知; 柴田 淳広; 佐野 雄一; 小泉 務

Procedia Chemistry, 7, p.77 - 83, 2012/00

 被引用回数:18 パーセンタイル:97.48



Salt-free technique for solvent washing process in NEXT process

佐野 雄一; 鍛治 直也; 柴田 淳広; 竹内 正行; 鷲谷 忠博

Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 7 Pages, 2011/12

As a part of the development of the advanced aqueous reprocessing process which aims at eliminating low radioactive waste containing sodium salt, we studied some salt-free techniques for solvent washing process which is one of the main sources of sodium salt waste in the conventional PUREX process. The batch-wise and counter-current solvent washing experiments were carried out with salt-free reagents, hydrazine carbonate and hydrazine oxalate, and genuine spent solvent. The phase separation behavior and solvent washing efficiency, i.e. DF of Pu, some FP and DBP, were investigated in these experiments, and it was confirmed that the salt-free reagents showed the almost same performance as sodium salt, Na$$_{2}$$CO$$_{3}$$, under the appropriate solvent washing condition. In addition to these solvent washing experiments, decomposition methods of spent reagents containing impurities, such as DBP, were also investigated. Several beaker-scale experiments for electrooxidative or thermal decomposition were carried out with the salt-free reagents containing the simulated impurities. These experimental results clarified the degradation behavior of hydrazine and oxalic ions in the salt-free reagents, and indicated that the generation of explosive degradation products, i.e. hydrogen azide and ammonium, could be kept low enough to avoid an explosive hazard.

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