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Zhao, X.*; Zhang, Z.*; 服部 高典; Wang, J.*; Li, L.*; Jia, Y.*; Li, W.*; Xue, J.*; Fan, X.*; Song, R.*; et al.
Nature Communications (Internet), 16, p.7713_1 - 7713_8, 2025/08
被引用回数:0 パーセンタイル:0.00熱効果は、固体状態の冷凍技術の一つの解決策の基盤を成すもので、通常は固体状態の相転移付近で発生し、冷凍温度範囲が限定されている。ここでは、前例のない概念である「全温度帯バロカロリック効果」を導入し実現する。すなわち、KPF
において77.5Kから300Kの極めて広い温度範囲(潜在的に4Kまで)で観測される顕著なバカカロリック効果である。この温度範囲は、一般的な室温、液体窒素、液体水素、液体ヘリウムの冷却領域をカバーしている。直接測定されたバーカロリック断熱温度変化は、250MPaの圧力を解放した際に、室温で12K、77.5Kで2.5Kに達する。この効果は、圧力依存性の中性子粉末回折、ラマン散乱解析、第一原理計算により示されるように、菱面体高圧相への持続的な相転移に起因する。構造的不安定性を考慮した熱力学的エネルギーランドスケープを記述する。この独自の全温度帯バロカロリック効果は、従来の多段式シナリオを超えた、高度に適用可能な固体状態冷凍技術への新たなアプローチを提供する。
Yang, X.*; Che, G.*; Wang, Y.*; Zhang, P.*; Tang, X.*; Lang, P.*; Gao, D.*; Wang, X.*; Wang, Y.*; 服部 高典; et al.
Nano Letters, 25(3), p.1028 - 1035, 2025/01
被引用回数:2 パーセンタイル:82.57(Chemistry, Multidisciplinary)飽和sp
-カーボンナノスレッド(CNTh)は、その高いヤング率と熱伝導率が予測され、大きな関心を集めている。中心環へのヘテロ原子の導入がCNThの形成に影響を与え、化学的に均質な生成物が得られることが示されているが、ペンダント基が重合プロセスに与える影響については、まだ未解明である。本研究では、フェノールの圧力誘起重合を調べ、0.5GPaと4GPa以下で起こる2つの相転移を明らかにした。20GPa以上では、フェノールは水酸基とカルボニル基を持つ重合度4のCNTに重合する。ヒドロキシル基の水素移動は、重合度6のナノスレッドの形成を妨げることがわかった。この発見は、さらなるカラム内重合を阻止する水酸基の重要な役割を浮き彫りにし、今後のメカニズム研究やナノ材料合成に貴重な示唆を与えるものである。
-Ti alloyZhang, B.*; Xin, S.*; Huang, M.*; Mao, W.; Jia, W.*; Li, Q.*; Li, S.*; Zhang, S.*; Mao, C.*
Materials Science & Engineering A, 890, p.145898_1 - 145898_7, 2024/01
被引用回数:0 パーセンタイル:0.00(Nanoscience & Nanotechnology)本研究では、高Zr-
-Ti合金の変形温度を300Kから77Kに下げると回復ひずみが2.25%から5.5%に大幅に増加することを報告した。この合金の超弾性は77Kにおいて
粒径に依存しないことがわかった。その結果、粗粒試料は77Kで超微粒試料とほぼ同じ超弾性を示すことがわかった。変形誘起マルテンサイト変態と転位すべりの相対的な容易さは77Kで大きく変化し、転位すべりは強く抑制され、超弾性に対する結晶粒の微細化の影響は影を潜めた。
Zhang, A.*; Deng, K.*; Sheng, J.*; Liu, P.*; Kumar, S.*; 島田 賢也*; Jiang, Z.*; Liu, Z.*; Shen, D.*; Li, J.*; et al.
Chinese Physics Letters, 40(12), p.126101_1 - 126101_8, 2023/12
被引用回数:12 パーセンタイル:83.20(Physics, Multidisciplinary)In a Dirac semimetal, the massless Dirac fermion has zero chirality, leading to surface states connected adiabatically to a topologically trivial surface state as well as vanishing anomalous Hall effect. Recently, itis predicted that in the nonrelativistic limit of certain collinear antiferromagnets, there exists a type of chiral "Dirac-like" fermion, whose dispersion manifests four-fold degenerate crossing points formed by spin-degenerate linear bands, with topologically protected Fermi arcs. Here, by combining with neutron diffraction and first-principles calculations, we suggest a multidomain collinear antiferromagnetic configuration, rendering the existence of the Fermi-arc surface states induced by chiral Dirac-like fermions.
Yuan, X.*; Hu, Q.*; Lin, X.*; Zhao, C.*; Wang, Q.*; 舘 幸男; 深津 勇太; 濱本 昌一郎*; Siitari-Kauppi, M.*; Li, X.*
Journal of Hydrology, 618, p.129172_1 - 129172_15, 2023/03
被引用回数:6 パーセンタイル:61.71(Engineering, Civil)Mass transport in geomedia as influenced by the pore structure is an important phenomenon. Six rocks (granodiorite, limestone, two chalks, mudstone, and dolostone) with different extents of heterogeneity at six different particle sizes were studied to describe the effects of pore connectivity on mass transport. The multiple methods applied were porosity measurement, gas diffusion test, and batch sorption test of multiple ions. Porosity measurement results reveal that with decreasing particle sizes, the effective porosities for the "heterogenous" group (granodiorite and limestone) increase, whereas the porosities of "homogeneous" group (chalks, mudstone, and dolostone) roughly remain constant. Gas diffusion results show that the intraparticle gas diffusion coefficient among these two groups, varying in the magnitude of 10
to 10
m
/s. The batch sorption work displays a different affinity of these rocks for tracers, which are related to their mineral components. For granodiorite, mudstone, and dolostone, the adsorption capacity increases as the particle size decreases, due to higher specific surface area in smaller particle-size. In general, this integrated research of grain size distribution, rock porosity, intraparticle diffusivity, and ionic sorption capacity gives insights into the pore connectivity effect on both gas diffusion and chemical transport behaviors for different lithologies and/or different particle sizes.
isomers in
CfOrlandi, R.; 牧井 宏之; 西尾 勝久; 廣瀬 健太郎; 浅井 雅人; 塚田 和明; 佐藤 哲也; 伊藤 由太; 洲嵜 ふみ; 永目 諭一郎*; et al.
Physical Review C, 106(6), p.064301_1 - 064301_11, 2022/12
被引用回数:5 パーセンタイル:55.72(Physics, Nuclear)The nuclear structure of
Cf produced by the
O+
Cf multinucleon transfer reaction was investigated using
-ray spectroscopy. Analysis of the
-ray spectrum of
Cf revealed the presence of multiple long-lived (isomeric) excited states at low excitation energies. The energies and half-lives of the isomers contain information on the proton and neutron orbits in the heavy-element region and the deformation of atomic nuclei, and are important data to predict the properties of nuclei in the "island of stability".
isomer in
Hg and
(
2) systematics of neutron transitions across the nuclear chartHuang, H.*; Zhang, W. Q.*; Andreyev, A. N.; Liu, Z.*; Seweryniak, D.*; Li, Z. H.*; Guo, C. Y.*; Barzakh, A. E.*; Van Duppen, P.*; Andel, B.*; et al.
Physics Letters B, 833, p.137345_1 - 137345_8, 2022/10
被引用回数:3 パーセンタイル:38.90(Astronomy & Astrophysics)The decay of the 13/2
isomeric state in
Hg was observed for the first time following the
decay of the 13/2
isomer in
Pb produced in the
Nd
Cr
reaction. Using
-
delayed coincidence measurements, the half-life of this isomer was measured to be 290(30)
s. This isomer is proposed to deexcite by an unobserved low-energy
2 transition to the known 9/2
member of a strongly prolate-deformed 7/2
[514] band, followed by a 105-keV
1 transition to the bandhead. A lower limit of B(
2)
0.018 W.u. was deduced for the unobserved transition. The presumed retardation is proposed to be due to the notable shape change between the initial, nearly spherical, and the final, strongly deformed, states. A similar scenario is also considered for the 13/2
isomer in
Hg, suggesting both are cases of shape isomers. The B(
2) systematics of neutron transitions across the nuclear chart is discussed.
PbZhang, W. Q.*; Andreyev, A. N.; Liu, Z.*; Seweryniak, D.*; Huang, H.*; Li, Z. H.*; Li, J. G.*; Guo, C. Y.*; 他34名*
Physics Letters B, 829, p.137129_1 - 137129_7, 2022/06
被引用回数:7 パーセンタイル:66.54(Astronomy & Astrophysics)Prompt and delayed
-ray spectroscopy of the neutron-deficient, semi-magic isotope
Pb has been performed at the Argonne Gas-Filled Analyzer. A new 5.15(15)-
s isomeric state at only 308 keV above the spherical 3/2
ground state is identified and classified as a shape isomer. A strongly-coupled band is observed on top of the isomer, which is nearly identical to the one built on the prolate 7/2
[514] Nilsson state in the isotone
Hg. Based on this similarity and on the result of the potential-energy surface calculations, the new isomer in
Pb is proposed to originate from the same configuration. The retarded character of the 308-keV transition can be well explained by the significant difference between the prolate parent and spherical daughter configurations, leading to the shape isomerism. The combined results of the present work and the previous
-decay and laser spectroscopy studies present evidence for triple shape coexistence at low energy in the negative-parity configurations of
Pb, which is well reproduced by the potential-energy surface calculations.
Wang, Y.*; Jia, G.*; Cui, X.*; Zhao, X.*; Zhang, Q.*; Gu, L.*; Zheng, L.*; Li, L. H.*; Wu, Q.*; Singh, D. J.*; et al.
Chem, 7(2), p.436 - 449, 2021/02
被引用回数:316 パーセンタイル:99.76(Chemistry, Multidisciplinary)Nanozymes are promising alternatives to natural enzymes, but their use remains limited owing to poor specificity. Overcoming this is extremely challenging due to the intrinsic structural complexity of these systems. We report theoretical design and experimental realization of a series of heterogeneous molybdenum single-atom nanozymes (named Mo
-N
-C), wherein we find that the peroxidase-like specificity is well regulated by the coordination numbers of single Mo sites. The resulting Mo
-N
-C catalyst shows exclusive peroxidase-like behavior. It achieves this behavior via a homolytic pathway, whereas Mo
-N
-C and Mo
-N
-C catalysts have a different heterolytic pathway. The mechanism of this coordination-number-dependent enzymatic specificity is attributed to geometrical structure differences and orientation relationships of the frontier molecular orbitals.
Sn; First measurement of low-lying
-emitting isomers in
AgChen, Z. Q.*; Li, Z. H.*; Hua, H.*; 渡邉 寛*; Yuan, C. X.*; Zhang, S. Q.*; Lorusso, G.*; Orlandi, R.; 他60名*
Physical Review Letters, 122(21), p.212502_1 - 212502_6, 2019/05
被引用回数:29 パーセンタイル:81.22(Physics, Multidisciplinary)
-delayed
-ray spectroscopy of the neutron-rich isotopes
Ag was carried out at RIBF, RIKEN. The long predicted 1/2
emitting isomers were identified in both nuclei for the first time. The new experimental results extend the systematic trend of energy spacing between the lowest 9/2
and 1/2
levels in Ag isotopes up to N=78, providing a clear signal for the reduction of the Z=40 subshell gap in Ag towards N=82. The tensor force is found to play a key role in the reduction of the Z=40 sub-shell gap.
Yang, P.-J.*; Li, Q.-J.*; 都留 智仁; 尾方 成信*; Zhang, J.-W.*; Sheng, H.-W.*; Shan, Z.-W.*; Sha, G.*; Han, W.-Z.*; Li, J.*; et al.
Acta Materialia, 168, p.331 - 342, 2019/04
被引用回数:89 パーセンタイル:97.12(Materials Science, Multidisciplinary)ニオブなどの体心立方構造をもつ金属材料は低濃度の酸素固溶によって脆化しやすいことが知られているが、酸素誘起の硬化や損傷の機構は明らかになっていない。我々は、実験、および第一原理計算と分子動力学計算を用いて詳細な機構を検討した。その結果、酸素の格子間原子はらせん転位と引力相互作用を生じ、それによって転位運動でクロスキンクが生成され、同時に多くの空孔が生成されることを明らかにした。これらの空孔はさらに酸素と転位の三体間の硬化によって転位の運動を阻害することで、著しい硬化を生じることを明らかにした。
Li, B.; Wang, H.*; 川北 至信; Zhang, Q.*; Feygenson, M.*; Yu, H. L.*; Wu, D.*; 尾原 幸治*; 菊地 龍弥*; 柴田 薫; et al.
Nature Materials, 17(3), p.226 - 230, 2018/03
被引用回数:171 パーセンタイル:97.50(Chemistry, Physical)As a generic property, all substances transfer heat through microscopic collisions of constituent particles. A solid conducts heat through both transverse and longitudinal acoustic phonons, but a liquid employs only longitudinal vibrations. As a result, a solid is usually thermally more conductive than a liquid. In canonical viewpoints, such a difference also serves as the dynamic signature distinguishing a solid from a liquid. Here, we report liquid-like thermal conduction observed in the crystalline AgCrSe
. The transverse acoustic phonons are completely suppressed by the ultrafast dynamic disorder while the longitudinal acoustic phonons are strongly scattered but survive, and are thus responsible for the intrinsically ultralow thermal conductivity. This scenario is applicable to a wide variety of layered compounds with heavy intercalants in the van der Waals gaps, manifesting a broad implication on suppressing thermal conduction. These microscopic insights might reshape the fundamental understanding on thermal transport properties of matter and open up a general opportunity to optimize performances of thermoelectrics.
Zr(
)
Zr cross section from the surrogate ratio method and its effect on
-process nucleosynthesisYan, S. Q.*; Li, Z. H.*; Wang, Y. B.*; 西尾 勝久; Lugaro, M.*; Karakas, A. I.*; 牧井 宏之; Mohr, P.*; Su, J.*; Li, Y. J.*; et al.
Astrophysical Journal, 848(2), p.98_1 - 98_8, 2017/10
被引用回数:9 パーセンタイル:30.80(Astronomy & Astrophysics)The
Zr(
)
Zr reaction cross section is crucial in the modelling of
-process nucleosynthesis in asymptotic giant branch stars because it controls the operation of the branching point at the unstable
Zr and the subsequent production of
Zr. We have carried out the measurement of the
Zr(
O,
O) and
Zr(
O,
O) reactions and obtained the
-decay probability ratio of
Zr
and
Zr
to determine the
Zr(
)
Zr reaction cross sections with the surrogate ratio method. We tested our deduced maxwellian-averaged cross section in stellar models with masses between 2 and 6
and metallicities 0.014 and 0.03. The largest changes - up 80 % variations in
Zr - are seen in the models of 3-4
, where the
Ne neutron source is mildly activated. The new rate can still provide a match to data from meteoritic stardust silicon carbide grains, provided the maximum mass of the parent stars is below 4
, for a metallicity of 0.03.
Qiu, Z.*; Li, J.*; Hou, D.*; Arenholz, E.*; N'Diaye, A. T.*; Tan, A.*; 内田 健一*; 佐藤 浩司*; 岡本 聡*; Tserkovnyak, Y.*; et al.
Nature Communications (Internet), 7, p.12670_1 - 12670_6, 2016/08
被引用回数:164 パーセンタイル:97.08(Multidisciplinary Sciences)Spin fluctuation and transition have always been one of the central topics of magnetism and condensed matter science. Experimentally, the spin fluctuation is found transcribed onto scattering intensity in the neutron-scattering process, which is represented by dynamical magnetic susceptibility and maximized at phase transitions. Importantly, a neutron carries spin without electric charge, and therefore it can bring spin into a sample without being disturbed by electric energy. However, large facilities such as a nuclear reactor are necessary. Here we show that spin pumping, frequently used in nanoscale spintronic devices, provides a desktop microprobe for spin transition; spin current is a flux of spin without an electric charge and its transport reflects spin excitation. We demonstrate detection of antiferromagnetic transition in ultra-thin CoO films via frequency-dependent spin-current transmission measurements, which provides a versatile probe for phase transition in an electric manner in minute devices.
Zr(n,
)
Zr cross section with
Zr(
O,
O)
Zr reactionsYan, S. Q.*; Li, Z. H.*; Wang, Y. B.*; 西尾 勝久; 牧井 宏之; Su, J.*; Li, Y. J.*; 西中 一朗; 廣瀬 健太郎; Han, Y. L.*; et al.
Physical Review C, 94(1), p.015804_1 - 015804_5, 2016/07
被引用回数:8 パーセンタイル:49.47(Physics, Nuclear)The relative
-decay probability ratios of the neutron resonance states in
Zr and
Zr populated via two neutron transfer reactions,
Zr(
O,
O)
Zr and
Zr(
O,
O)
Zr, have been measured to test the validity of the surrogate ratio method (SRM) in determining the (n,
) reaction cross section. The cross sections of the
Zr(n,
)
Zr reaction are derived from the experimentally obtained ratios and the cross sections of the
Zr(n,
)
Zr reaction in the equivalent neutron energy range of
= 0 - 8 MeV. The deduced cross sections of
Zr(n,
)
Zr reaction agree with the directly measured ones in the low-energy region, and with the evaluated ENDF/B-VII.1 data at higher energies of
3 MeV. The agreement supports the concept of the SRM method to indirectly determine the (n,
) reaction cross sections.

Li, B.; Luo, X. H.*; Wang, H.*; Ren, W. J.*; Yano, S.*; Wang, C.-W.*; Gardner, J. S.*; Liss, K.-D.*; Miao, P.*; Lee, S.-H.*; et al.
Physical Review B, 93(22), p.224405_1 - 224405_6, 2016/06
被引用回数:60 パーセンタイル:88.28(Materials Science, Multidisciplinary)Competition between ferromagnetic and antiferromagnetic phases on frustrated lattices in hexagonal Laves phase compound Hf
Ta
Fe
is investigated by using neutron diffraction as a function of temperature and magnetic fields and density-functional-theory calculations. At 325 K, the compound orders into the 120
frustrated antiferromagnetic state with well-reduced magnetic moment and an in-plane lattice contraction simultaneously sets in. With further cooling down, however, the accumulated distortion in turn destabilizes this susceptible frustrated structure. The frustration is completely relieved at 255 K when the first-order transition to the ferromagnetic state takes place, where a colossal negative volumetric thermal expansion,
/K, is obtained. Meanwhile, the antiferromagnetic state can be suppressed by few Tesla magnetic fields, which results in a colossal positive magnetostriction. Such delicate competition is attributed to the giant magnetic fluctuation inherent in the frustrated antiferromagnetic state. Therefore, the magnetoelastic instability is approached even under a small perturbation.
Wray, L. A.*; Huang, S.-W.*; Jarrige, I.*; 池内 和彦*; 石井 賢司; Li, J.*; Qiu, Z. Q.*; Hussain, Z.*; Chuang, Y.-D.*
Frontiers in Physics (Internet), 3, p.32_1 - 32_11, 2015/05
被引用回数:4In resonant inelastic X-ray scattering (RIXS), core hole resonance modes are used to enhance coupling between photons and low energy electronic degrees of freedom. Resonating with shallow core holes accessed in the extreme ultraviolet (EUV) can provide greatly improved energy resolution at standard resolving power, but has been found to often yield qualitatively different spectra than similar measurements performed with higher energy X-rays. This paper uses experimental data and multiplet-based numerical simulations for the M-edges of Co-, Ni-, and Cu-based Mott insulators to review the properties that distinguish EUV RIXS from more commonly performed higher energy measurements. Key factors such as the origin of the strong EUV elastic line and advantages of EUV spectral functions over soft X-ray RIXS for identifying intrinsic excitation line shapes are discussed.
output of Ar and Kr using size optimized cluster target irradiated by high-contrast laser pulsesZhang, L.*; Chen, L.-M.*; Yuan, D.-W.*; Yan, W.-C.*; Wang, Z.-H.*; Liu, C.*; Shen, Z.-W.*; Faenov, A.*; Pikuz, T. A.; Skobelev, I.*; et al.
Optics Express (Internet), 19(25), p.25812 - 25822, 2011/12
It was observed that increasing the clusters size and laser pulse contrast can enhance the X-ray flux emitted by femtosecond-laser-driven-cluster plasma. By focusing a high contrast laser (10
) on large argon and Kr clusters, high flux K-shell X-rays is generated with record conversion efficiency. Using this X-ray source, a single-shot high-performance X-ray imaging is demonstrated.
岸本 泰明; 三木 一弘*; Li, J. Q.*; 宮戸 直亮; Wang, Z. X.*; Anderson, J.*
Proceedings of 22nd IAEA Fusion Energy Conference (FEC 2008) (CD-ROM), 8 Pages, 2008/10
測地的音響モード(GAM)成長間欠性と呼ばれる、無衝突GAM減衰による新しいクラスの遷移輸送がランダウ流体シミュレーションに基づき発見された。ここでは、この成長する間欠性の基本的性質を理解するために新しいプレデター-プレイモデルを提出する。また、帯状流の衝突減衰を考慮することによりシミュレーションモデルの拡張も行う。2種類の減衰機構の混合により、この間欠性は再帰的に衝突(あるいは輸送)の時間スケールに及ぶ帯状流の複雑なエンベロープ変調を伴いながら現れることがわかった。さらに、1つの散逸機構として働く、臨界勾配近くの帯状圧力の効果も調べた。これら複数の散逸機構は互いに結合し、長い時間スケールにわたってプラズマに複雑な動的輸送を引き起こすことがわかった。
Li, J. Q.*; 岸本 泰明; 宮戸 直亮; 三木 一弘*; Anderson, J.*; Shi, B. R.*
Journal of Physics; Conference Series, 123, p.012027_1 - 012027_11, 2008/08
被引用回数:2 パーセンタイル:60.54(Physics, Fluids & Plasmas)トカマクプラズマ中の測地的音響モード(GAM)の非線形励起と飽和及びその径方向構造を新規に開発したジャイロ流体モデルを用いて調べる。第一にイオン温度勾配(ITG)揺動とGAMについての従来の3場ジャイロ流体モデル化に対する経験的クロージャー関係を提出する。帯状流の減衰について理論的予測や他の運動論的計算と比較することによって正確に調べられる。それから局所コード及びそのグローバル版がITG乱流によるGAMの非線形励起シミュレーションに用いられる。これによりGAM不安定性が非線形駆動と無衝突減衰との競合の下で非線形的に励起されることが発見される。GAM不安定性に対するポンプ波の振幅の閾値は帯状流不安定性のそれよりも高い。一方、不安定なGAMはおもにランダウ減衰により飽和する。これは静的な帯状流とは異なる。さらにGAMの径方向構造が
であることが示される。これは純粋な帯状流のそれよりも短い。