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Zhou, L.*; Zhang, H.*; Qin, T. Y.*; Hu, F. F.*; 徐 平光; Ao, N.*; Su, Y. H.; He, L. H.*; Li, X. H.*; Zhang, J. R.*; et al.
Metallurgical and Materials Transactions A, 11 Pages, 2024/00
被引用回数：0High-speed railway S38C axles undergo surface induction hardening for durability, but are susceptible to fatigue cracks from foreign object impact. The neutron diffraction method was employed to measure the residual strain in S38C axles, obtaining microscopic lattice distortion data, for the gradient layer at a depth of 8 mm under the surface. The results showed that after induction-hardening, the microscopic lattice distortion had a gradient distribution, decreasing with the distance from the surface. However, in the case of impacting speed of 600 km/m, the average microscopic lattice distortion increased with the distance from the surface, reaching a maximum augmentation of 55 pct. These findings indicate a strong experimental basis, and improve our understanding of the relationship between macroscopic residual stress and decision-making, in regard to operation and maintenance.
Jiang, X.*; 服部 高典; Xu, X.*; Li, M.*; Yu, C.*; Yu, D.*; Mole, R.*; 矢野 真一郎*; Chen, J.*; He, L.*; et al.
Materials Horizons, 10(3), p.977 - 982, 2023/03
被引用回数：5 パーセンタイル：87.86(Chemistry, Multidisciplinary)現在の蒸気圧縮式冷凍機に代わる環境に優しい冷凍機として、バロカロリック効果に基づく固体冷凍機が世界的に注目されている。一般に、バロカロリック効果が発現する相はいずれも常圧でも存在する。ここでは、それらの物質と違って、KPF
が高圧の菱面体晶相を生成することにより、巨大なバロカロリック効果を示すことを実証した。相図は、圧力依存の熱量測定、ラマン散乱測定、中性子回折測定に基づいて構築されたものである。本研究は、巨大バロカロリー効果に、高圧相の生成という新たな手法をもたらすと期待される。
二神 敏; 久保 重信; Sofu, T.*; Ammirabile, L.*; Gauthe, P.*
Proceedings of International Conference on Topical Issues in Nuclear Installation Safety; Strengthening Safety of Evolutionary and Innovative Reactor Designs (TIC 2022) (Internet), 10 Pages, 2022/10
In the framework of the GIF, an effort to develop Safety Design Criteria (SDC) for SFR systems was initiated in 2011. For this purpose, an SDC task force (SDC-TF) was formulated in July 2011. The SDC-TF members consist of representatives of CIAE (China), CEA (France), JAEA (Japan), KAERI, KINS (Republic of Korea), IPPE (Russia), ANL, INL, ORNL (United States of America), EC and IAEA. This paper describes the outline of the SDC and SDGs contents and its development background as shown above. These SDC and SDGs refer related IAEA safety standards, such as SSR-2/1 Safety of Nuclear Power Plants: Design, SSG-52 Design of the Reactor Core for Nuclear Power Plants. This paper focuses on both technology neutral aspects, which are common parts between the SDC/SDG and IAEA standards, and SFR specific aspects.
Gatera, A.*; Belmans, J.*; Boussa, S.*; Davin, F.*; De Cock, W.*; De Florio, V.*; Doucet, F.*; Parez, L.*; Pompon, F.*; Ponton, A.*; et al.
Proceedings of 64th ICFA Advanced Beam Dynamics Workshop on High Intensity and High Brightness Hadron Beams (HB2021), p.186 - 190, 2022/04
The MYRRHA project at SCK CEN, Belgium, aims at coupling a 600 MeV proton accelerator to a subcritical fission core operating at a thermal power of 60 MW. The nominal proton beam for this ADS has an intensity of 4 mA and is delivered in a quasi-CW mode. MYRRHA's linac is designed to be fault tolerant thanks to redundancy implemented in parallel at low energy and serially in the superconducting linac. Phase 1 of the project, named MINERVA, will realise a 100 MeV, 4 mA superconducting linac with the mission of demonstrating the ADS requirements in terms of reliability and of fault tolerance. As part of the reliability optimisation program the integrated prototyping of the MINERVA injector is ongoing at SCK CEN in Louvain-la-Neuve, Belgium. The injector test stand aims at testing sequentially all the elements composing the front-end of the injector. This contribution will highlight the beam dynamics choices in MINERVA's injector and their impact on ongoing commissioning activities.
mesocrystal formationLi, Z.*; Piankova, D.*; Yang, Y.*; 熊谷 友多; Zschiesche, H.*; Jonsson, M.*; Tarakina, N. V.*; Soroka, I. L.*
Angewandte Chemie; International Edition, 61(6), p.e202112204_1 - e202112204_9, 2022/02
被引用回数：4 パーセンタイル：30.82(Chemistry, Multidisciplinary)Ce(III)水溶液の放射線誘起酸化反応によるCeO形成過程を研究した。Ce(III)はガンマ線照射による水の放射線分解で生じるOHラジカルによりCe(IV)に酸化され、水に対する溶解度が減少するため析出し、最終的にはCeOが生成する。この反応過程を透過型電子顕微鏡観察とX線結晶構造解析を用いて調べた。その結果、ガンマ線照射によって生成するCeOは、いくつかの中間的な状態を経てメソ結晶体を形成することを明らかにした。水溶液中でCe(III)が酸化されると、CeO析出の前駆体としてアモルファスなCe(IV)水酸化物が生成する。その後、Ce(IV)水酸化物中でCeOのナノ粒子が成長する。このCeOナノ粒子はアモルファス組織の中でゆっくりと配向性を有するようになり、ナノ粒子間の相互作用により規則的な構造を形成したメソ結晶体となる。さらに、このメソ結晶体を徐々に乾燥させることでメソ結晶体がさらに構造化した超結晶(supracrystal)となり、複雑な階層化アーキテクチャが形成されることを明らかにした。
Naeem, M.*; He, H.*; Harjo, S.; 川崎 卓郎; Lin, W.*; Kai, J.-J.*; Wu, Z.*; Lan, S.*; Wang, X.-L.*
Acta Materialia, 221, p.117371_1 - 117371_18, 2021/12
被引用回数：31 パーセンタイル：94.34(Materials Science, Multidisciplinary)We studied the deformation behavior of CrFeCoNi high-entropy alloy by in situ neutron diffraction at room temperature, intermediate low temperature of 140 K, low temperatures of 40 K (no serrated deformation) and 25 K (with massive serrations). The contributions from different deformation mechanisms to the yield strength and strain hardening have been estimated. The athermal contributions to the yield strength were 
183 MPa at all temperatures, while the Peierls stress increased significantly at low temperatures (from 148 MPa at room temperature to 493 MPa at 25 K). Dislocations contributed to 94% strain hardening at room temperature. Although the dislocation strengthening remained the major hardening mechanism at very low temperatures, the planar faults contribution increased steadily from 6% at room temperature to 28% at 25 K.
Barucci, M. A.*; Reess, J.-M.*; Bernardi, P.*; Doressoundiram, A.*; Fornasier, S.*; Le Du, M.*; 岩田 隆浩*; 中川 広務*; 中村 智樹*; Andr
, Y.*; et al.
Earth, Planets and Space (Internet), 73(1), p.211_1 - 211_28, 2021/12
被引用回数：13 パーセンタイル：80.63(Geosciences, Multidisciplinary)MMX赤外線分光計(MIRS)は、宇宙航空研究開発機構(JAXA)のMMXミッションに搭載されているイメージング分光計である。MIRSは他の4つのフランス研究所との協力、フランス国立宇宙研究センター(CNES)の協力と財政支援、およびJAXAと三菱電機(MELCO)との緊密な協力によりパリ天文台で開発されている。この装置はMMXの科学的目的を完全に達成するべく設計されている。MIRSはフォボスとダイモスの表面組成の分析およびサンプリングサイトの選択時に使用される組成診断スペクトル機能を含む近赤外線スペクトルマップ機能をリモートで提供する。MIRSはまた、火星の大気、特に雲,塵,水蒸気などの空間的時間的変化についても観測を行う予定である。
Naeem, M.*; Zhou, H.*; He, H.*; Harjo, S.; 川崎 卓郎; Lan, S.*; Wu, Z.*; Zhu, Y.*; Wang, X.-L.*
Applied Physics Letters, 119(13), p.131901_1 - 131901_7, 2021/09
被引用回数：9 パーセンタイル：62.1(Physics, Applied)We investigated the in situ deformation behavior of the CrCoNi medium-entropy alloy at a cryogenic temperature of 140 K and compared it with deformation at room temperature. The sample exhibited higher strength and larger ductility at the cryogenic temperature. The CrCoNi alloy remained single-phase face-centered cubic at room temperature, while deformation at 140 K resulted in a martensitic transformation to the hexagonal close-packed structure. The phase transformation, an additional deformation mechanism to stacking faults, twinning, and dis- location slip, resulted in a higher work hardening at cryogenic temperature. The study addresses the structure metastability in the CrCoNi alloy, which led to the formation of epsilon-martensite from the intrinsic stacking faults.
Gatera, A.*; Belmans, J.*; Davin, F.*; De Cock, W.*; Doucet, F.*; Parez, L.*; Pompon, F.*; Ponton, A.*; Vandeplassche, D.*; Bouly, F.*; et al.
Proceedings of 12th International Particle Accelerator Conference (IPAC 21) (Internet), p.675 - 678, 2021/08
The MYRRHA project aims at coupling a 600 MeV proton accelerator to a subcritical fission core operating at a thermal power of 70 MW. The nominal proton beam for this ADS (Accelerator Driven System) has an intensity of 4 mA and is delivered in a quasi-CW mode. Phase 1 of the project will realise a 100 MeV, 4 mA superconducting linac with the mission of ensuring the ADS requirements in terms of reliability and fault tolerance. As part of the reliability optimisation program the integrated prototyping of the MINERVA injector is ongoing. The front-end of the injector is composed of an ECR proton source, an LEBT (Low Energy Beam Transport line) and a four-rod RFQ accelerating the beam to 1.5 MeV. The present contribution focuses on the current beam tests on the RFQ, including beam matching, RF conditioning, assessment of the cavities' performances and accelerated beam characterisation.
Jaffe, A. L.*; Thomas, A. D.*; He, C.*; Keren, R.*; Valentin-Alvarado, L. E.*; Munk, P.*; Bouma-Gregson, K.*; Farag, I. F.*; 天野 由記; Sachdeva, R.*; et al.
mBio, 12(4), p.e00521-21_1 - e00521-21_21, 2021/08
被引用回数：21 パーセンタイル：89.98(Microbiology)Candidate Phyla Radiation (CPR) bacteria are small, likely episymbiotic organisms found across Earth's ecosystems. Despite their prevalence, the distribution of CPR lineages across habitats and the genomic signatures of transitions amongst these habitats remain unclear. Hear, we expand the genome inventory for Absconditabacteria (SR1), Gracilibacteria, and Saccharibacteria (TM7), CPR bacteria known to occur in both animal-associated and environmental microbiomes, and investigate variation in gene content with habitat of origin. By overlaying phylogeny with habitat information, we show that bacteria from these three lineages have undergone multiple transitions from environmental habitats into animal microbiomes. Based on co-occurrence analyses of hundreds of metagenomes, we extend the prior suggestion that certain TM7 have broad bacterial host ranges and constrain possible host relationships for SR1 and Gracilibacteria. Full-proteome analyses show that animal-associated TM7 have smaller gene repertoires than their environmental counterparts and are enriched in numerous protein families, including those likely functioning in amino acid metabolism, phage defense, and detoxification of peroxide. In contrast, some freshwater TM7 encodea putative rhodopsin. For protein families exhibiting the clearest patterns of differential habitat distribution, we compared protein and species phylogenies to estimate the incidence of lateral gene transfer and genomic loss occurring over the species tree. These analyses suggest that habitat transitions were likely not accompanied by large transfer or loss events, but rather were associated with continuous proteome remodeling. Thus, we speculate that CPR habitat transitions were driven largely by availability of suitable host taxa, and were reinforced by acquisition and loss of some capacities.
He, H.*; Naeem, M.*; Zhang, F.*; Zhao, Y.*; Harjo, S.; 川崎 卓郎; Wang, B.*; Wu, X.*; Lan, S.*; Wu, Z.*; et al.
Nano Letters, 21(3), p.1419 - 1426, 2021/02
被引用回数：41 パーセンタイル：95.34(Chemistry, Multidisciplinary)In CrCoNi, a so-called medium-entropy alloy, an fcc-to-hcp phase transformation has long been anticipated. Here, we report an in situ loading study with neutron diffraction, which revealed a bulk fcc-to-hcp phase transformation in CrCoNi at 15 K under tensile loading. By correlating deformation characteristics of the fcc phase with the development of the hcp phase, it is shown that the nucleation of the hcp phase was triggered by intrinsic stacking faults. The confirmation of a bulk phase transformation adds to the myriads of deformation mechanisms available in CrCoNi, which together underpin the unusually large ductility at low temperatures.
are metabolically diverse compared to gut microbiome and some have a novel nitrogenase paralogMheust, R.*; Castelle, C. J.*; Matheus Carnevali, P. B.*; Farag, I. F.*; He, C.*; Chen, L.-X.*; 天野 由記; Hug, L. A.*; Banfield, J. F.*
ISME Journal, 14(12), p.2907 - 2922, 2020/12
被引用回数：39 パーセンタイル：94.42(Ecology)We reconstructed 94 draft-quality, non-redundant genomes from diverse animal-associated and natural environments. Genomes group into 12 clades, 10 of which previously lacked reference genomes. Groundwater-associated are predicted to be capable of heterotrophic or autotrophic lifestyles, reliant on oxygen or nitrate/nitrite-dependent respiration of fatty acids, or a variety of organic compounds and Rnf-dependent acetogenesis with hydrogen and carbon dioxide as the substrates. Genomes from two clades of groundwater-associated often encode a new homologous group of nitrogenase-like proteins that co-occur with an extensive suite of radical SAM-based proteins. We identified similar genomic loci in genomes of bacteria from the Gracilibacteria and Myxococcus phyla and predict that the gene clusters reduce a tetrapyrrole, possibly to form a novel cofactor. The animal-associated clades nest phylogenetically within two groundwater-associated clades. Thus, we propose an evolutionary trajectory in which some adapted to animal-associated lifestyles from groundwater-associated species via genome reduction.
Khuyagbaatar, J.*; Yakushev, A.*; D
llmann, Ch. E.*; Ackermann, D.*; Andersson, L.-L.*; 浅井 雅人; Block, M.*; Boll, R. A.*; Brand, H.*; Cox, D. M.*; et al.
Physical Review C, 102(6), p.064602_1 - 064602_9, 2020/12
被引用回数：43 パーセンタイル：98.01(Physics, Nuclear)原子番号119及び120を持つ超重元素の合成を目指した探索実験を、それぞれ
Ti+
Bk及びTi+Cf核融合-粒子蒸発反応を用いて、ガス充填型反跳分離装置TASCAにて実施した。4ヶ月間におよぶビーム照射実験を行ったが、どちらの元素も検出されず、その生成断面積の上限値は65fb及び200fbであった。119, 120番元素が観測されなかった理由について、安定の島領域の超重元素の核分裂障壁の高さを予測する様々な理論計算値を用いて、核融合-粒子蒸発反応の概念を用いて議論した。
Naeem, M.*; He, H.*; Harjo, S.; 川崎 卓郎; Zhang, F.*; Wang, B.*; Lan, S.*; Wu, Z.*; Wu, Y.*; Lu, Z.*; et al.
Scripta Materialia, 188, p.21 - 25, 2020/11
被引用回数：56 パーセンタイル：97.51(Nanoscience & Nanotechnology)The deformation behavior of CrMnFeCoNi high entropy alloy was investigated by in situ neutron diffraction at an ultralow temperature of 15 K. Analysis of the diffraction peak widths showed an extremely high dislocation density at 15 K, reaching 10
m
. In addition, the dislocation density was found to closely follow the development of texture caused by deformation. In contrast to deformation by dislocation slip at room temperature, the ultralow-temperature deformation also involved stacking faults, twinning and serrations. The deformation pathway at ultralow temperature is outlined which is responsible for the extraordinary strength-ductility combination.
Prez S
nchez, R.*; Jurado, B.*; Mot, V.*; Roig, O.*; Dupuis, M.*; Bouland, O.*; Denis-Petit, D.*; Marini, P.*; Mathieu, L.*; Tsekhanovich, I.*; et al.
Physical Review Letters, 125(12), p.122502_1 - 122502_5, 2020/09
被引用回数：13 パーセンタイル：70.32(Physics, Multidisciplinary)Reliable neutron-induced-reaction cross sections of unstable nuclei are essential for nuclear astrophysics and applications but their direct measurement is often impossible. The surrogate-reaction method is one of the most promising alternatives to access these cross sections. In this work, we successfully applied the surrogate-reaction method to infer for the first time both the neutron-induced fission and radiative capture cross sections of 
Pu in a consistent manner from a single measurement. This was achieved by combining simultaneously measured fission and 
-emission probabilities for the 
Pu(
He, He') surrogate reaction with a calculation of the angular-momentum and parity distributions populated in this reaction. While other experiments measure the probabilities for some selected -ray transitions, we measure the -emission probability. This enlarges the applicability of the surrogate-reaction method.
Guo, J.*; Zhao, X.*; 河村 聖子; Ling, L.*; Wang, J.*; He, L.*; 中島 健次; Li, B.*; Zhang, Z.*
Physical Review Materials (Internet), 4(6), p.064410_1 - 064410_7, 2020/06
被引用回数：10 パーセンタイル：48.03(Materials Science, Multidisciplinary)NaYbO has been reported as a possible host for the quantum spin-liquid state. Here, the composition-dependent polycrystalline Na
YbO (
, 0.03, and 0.07) has been investigated by combining high-field magnetizations and inelastic neutron scattering techniques. For the sample, no signature of a magnetic order is observed down to 0.3 K. Inelastic neutron scattering measurement suggests a continuous low-energy excitation spectrum centered at momentum transfer 
~
and extending up to energy transfer 
~meV. In contrast, 
and 0.07 samples exhibit magnetic transitions at 1.1 and 2.3 K, respectively. High-field magnetization measurements indicate similar behaviors for and 0.03 samples including plateau-like features at the 1/3 saturated magnetization, which implies that the spin disorder in the sample might be suppressed preceding the emergence of the up-up-down phase. This composition- and field-dependent study allows us to construct complete phase diagrams indicating that NaYbO is a promising candidate for the quantum spin-liquid state in close proximity to the antiferromagnetic instability tuned by the application of magnetic fields as well as controlling the concentration of Na
ion vacancies.
Woo, W.*; Naeem, M.*; Jeong, J.-S.*; Lee, C.-M.*; Harjo, S.; 川崎 卓郎; He, H.*; Wang, X.-L.*
Materials Science & Engineering A, 781, p.139224_1 - 139224_7, 2020/04
被引用回数：38 パーセンタイル：93.57(Nanoscience & Nanotechnology)To elucidate deformation behavior behind the exceptional mechanical properties of CrCoNi based medium entropy alloys, the deformation related microstructural parameters were determined by using in situ neutron diffraction and peaks profile analysis methods. Superior tensile strength and elongation of the CrCoNi alloy is relevant to higher twin fault probability (
, up to 3.8%) and dislocation density (
, up to 9.7 
10
m) compared to those (1.3% and 3.4 10 m, respectively) of the CrCoNiFe at 293K. Meanwhile, at 140K, the of the CrCoNiFe significantly increased up to 4.4% with the stable of 5.0 10 m and its mechanical properties overwhelm those of the CrCoNi at 273K. Such twinning dominant deformation mechanism at low temperature is also assured by lower stacking fault energy (SFE) of the CrCoNiFe at 140K compared to those of the CrCoNi and CrCoNiFe alloys at 293K.
Naeem, M.*; He, H.*; Zhang, F.*; Huang, H.*; Harjo, S.; 川崎 卓郎; Wang, B.*; Lan, S.*; Wu, Z.*; Wang, F.*; et al.
Science Advances (Internet), 6(13), p.eaax4002_1 - eaax4002_8, 2020/03
被引用回数：145 パーセンタイル：99.09(Multidisciplinary Sciences)High-entropy alloys exhibit exceptional mechanical properties at cryogenic temperatures, due to the activation of twinning in addition to dislocation slip. The coexistence of multiple deformation pathways raises an important question regarding how individual deformation mechanisms compete or synergize during plastic deformation. Using in situ neutron diffraction, we demonstrate the interaction of a rich variety of deformation mechanisms in high-entropy alloys at 15 K, which began with dislocation slip, followed by stacking faults and twinning, before transitioning to inhomogeneous deformation by serrations. Quantitative analysis showed that the cooperation of these different deformation mechanisms led to extreme work hardening. The low stacking fault energy plus the stable face-centered cubic structure at ultralow temperatures, enabled by the high-entropy alloying, played a pivotal role bridging dislocation slip and serration.
Al-Shayeb, B.*; Sachdeva, R.*; Chen, L.-X.*; Ward, F.*; Munk, P.*; Devoto, A.*; Castelle, C. J.*; Olm, M. R.*; Bouma-Gregson, K.*; 天野 由記; et al.
Nature, 578(7795), p.425 - 431, 2020/02
被引用回数：220 パーセンタイル：99.5(Multidisciplinary Sciences)Phage typically have small genomes and depend on their bacterial hosts for replication. We generated metagenomic datasets from many diverse ecosystems and reconstructed hundreds of huge phage genomes, between 200 kbp and 716 kbp in length. Thirty four genomes were manually curated to completion, including the largest phage genomes yet reported. Expanded genetic repertoires include diverse and new CRISPR-Cas systems, tRNAs, tRNA synthetases, tRNA modification enzymes, initiation and elongation factors and ribosomal proteins. Phage CRISPR have the capacity to silence host transcription factors and translational genes, potentially as part of a larger interaction network that intercepts translation to redirect biosynthesis to phage-encoded functions. Some phage repurpose bacterial systems for phage-defense to eliminate competing phage. We phylogenetically define seven major clades of huge phage from human and other animal microbiomes, oceans, lakes, sediments, soils and the built environment. We conclude that large gene inventories reflect a conserved biological strategy, observed across a broad bacterial host range and resulting in the distribution of huge phage across Earth's ecosystems.
-MgAgSbLi, X.*; Liu, P.-F.*; Zhao, E.*; Zhang, Z.*; Guide, T.*; Le, M. D.*; Avdeev, M.*; 池田 一貴*; 大友 季哉*; 古府 麻衣子; et al.
Nature Communications (Internet), 11, p.942_1 - 942_9, 2020/02
被引用回数：36 パーセンタイル：90.35(Multidisciplinary Sciences)高性能の熱電材料実現には低熱伝導率が必要であり、その機構としてはフォノンの非調和によるもの、あるいは、結晶構造の動的な乱れによるフォノンの散乱によるものがあげられ、どちらも中性子散乱でその現象が明らかにされている。我々は中性子散乱と第一原理計算を組み合わせ、-MgAgSbにおいて、静的な結晶構造の乱れとフォノンの非調和性が組み合わされて極端に低い熱伝導率が実現されているということを見いだしたので、これを報告する。
