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Magnetic reversal and magnetic memory effect in melt-spun Pr_2Fe_(14)b/α-Fe nanocomposite ribbons

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Journal of Rare Earths 2015年第12期33卷 1303-1309页

作者：韩广兵苏浩高汝伟于淑云康仕寿朱明刚李卫 x.b.liu School of Physics Shandong University Division of Functional Materials Central Iron & Steel Research Institute Department of Physics University of Texas at Arlington

The influence of CoCr addition on the microstructure and magnetic properties was investigated in nanocomposite Pr2Fel4b/a-Fe alloys prepared by melt spinning. It was shown that the magnetic properties of Pr2Fel4b/ct-Fe nanocomposite were im- proved by an addition of 10 at.% CoCr, in particular, coercivity （Hc） from 4.9 up to 5.3 kOe, maximum energy product （（bH）max） from 10.6 up to 13.9 MGOe, and remanence （Mr） from 94.2 up to 98.4 emu/g. The field dependencies of the reversible and irreversible magnetization components were derived from the recoil loops. Combining with the initial magnetization curves, the results indi- cated that the pinning of domain walls at the grain boundaries dominated the magnetization reversal in Pr2Fe14b/ct-Fe nanocomposite alloys. The magnetic memory effect was studied by measuring the magnetic moment relaxation at a cycle negative magnetic field with time interval of 600 s. The exchange-spring magnets with magnetic memory effect have a high potential for high density magnetic recording.

关键词： magnetization reversal exchange coupling magnetic memory effect nanocomposite alloys coercivity rare earths

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2型糖尿病病人异常皮质下核形状的研究

国际医学放射学杂志 2017年第6期 743-743页

作者： J.Chen J.x.Zhang x.b.liu x.Y.Wang x.J.xu H.Li 刘瑶 Department of Medical Imaging Fuzhou General Hospital

摘要目的 2型糖尿病(T2DM)增加脑萎缩以及痴呆的患病风险。旨在通过结合基于兴趣区(ROI)的体积测定、基于体素的形态测定(VbM)和形状分析来阐明深部灰质(GM)结

关键词： VbM GM 形态分析结构异常

Potential of ultrasound stimulation and sonogenetics in vision restoration:a narrative review

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Neural Regeneration Research 2025年第12期20卷 3501-3516页

作者： Jie Ji Chen Gong Gengxi Lu Junhang Zhang baoqiang liu xunan liu Junhao Lin Patrick Wang biju b.Thomas Mark S.Humayun Qifa Zhou Department of biomedical Engineering University of Southern CaliforniaLos AngelesCAUSA USC Roski Eye Institute Keck School of Medicine of University of Southern CaliforniaLos AngelesCAUSA Thomas Lord Department of Computer Science University of Southern CaliforniaLos AngelesCAUSA Harvard Westlake School Studio CityCAUSA

Vision restoration presents a considerable challenge in the realm of regenerative medicine,while recent progress in ultrasound stimulation has displayed potential as a non-invasive therapeutic *** narrative review offers a comprehensive overview of current research on ultrasound-stimulated neuromodulation,emphasizing its potential as a treatment modality for various nerve *** examining of the efficacy of different types of ultrasound stimulation in modulating peripheral and optic nerves,we can delve into their underlying molecular ***,the review underscores the potential of sonogenetics in vision restoration,which involves leveraging pharmacological and genetic manipulations to inhibit or enhance the expression of related mechanosensitive channels,thereby modulating the strength of the ultrasound *** also address how methods such as viral transcription can be utilized to render specific neurons or organs highly responsive to ultrasound,leading to significantly improved therapeutic outcomes.

关键词： neuromodulation non-invasive optic nerve injury retinal degeneration sonogenetics ultrasound stimulation visual restoration

New Taub-NUT black holes with massive spin-2 hair

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 51-58页

作者： Yu-Qi Chen Hai-Shan liu Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China

We consider Einstein gravity extended with quadratic curvature invariants,within which the well-known Ricci-flat Taub-NUT black hole remains a *** analysis of the unstable Lichnerowicz modes in the Taub-NUT background enables us to identify the mass and NUT parameters(m,n)where new Taub-NUT black holes can *** then adopt numerical techniques to construct these new Taub-NUT black holes,which bifurcate away from the Ricci-flat *** the Ricci-flat Taub-NUT,there can exist two new black holes for an appropriate given temperature,making it a total of three if we include the Ricci-flat one.

关键词： higher derivative gravity black hole solution Taub-NUT spacetime

Construction of eco-friendly dual carbon dots ratiometric fluorescence probe for highly selective and efficient sensing mercury ion

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Journal of Environmental Sciences 2025年第2期148卷 1-12页

作者： Yongli liu xiaoyan Su Huanjia liu Guifen Zhu Guobei Ge Yuxin Wang Penghui Zhou Qingxiang Zhou School of Environment Henan Key Laboratory for Environmental Pollution ControlKey Laboratory for Yellow River and Huai River Water Environmental and Pollution ControlMinistry of EducationHenan Normal UniversityXinxiang 453007China College of Chemical Engineering and Environment China University of Petroleum-BeijingBeijing 102249China

In present work,blue carbon dots(b-CDs)were derived from ammonium citrate and guanidine hydrochloride,and red carbon dots(r-CDs)were stemmed from malonate,ethylenediamine and meso-tetra(4-carboxyphenyl)porphin based on facile hydrothermal ***-friendly ratiometric fluorescence probe was innovatively constructed to effectively measure Hg2+utilizing b-CDs and *** developed probe displayed two typical emission peaks at 450 nm from b-CDs and 650 nm from r-CDs under the excitation at 360 *** ion has strong quenching effect on the fluorescence intensity at 450 nm due to the electron transfer process and the fluorescence change at 450 nm was used as the response signal,whereas the fluorescence intensity at 650 nm kept unchangeable which resulted from the chemical inertness between Hg^(2+)and r-CDs,serving as the reference signal in the sensing *** optimal circumstances,this probe exhibited an excellent linearity between the fluorescence response values of F450/F650 and Hg^(2+)concentrations over range of 0.01-10μmol/L,and the limit of detectionwas down to 5.3 nmol/***,this probe was successfully employed for sensing Hg^(2+)in practical environmental water samples with satisfied recoveries of 98.5%-105.0%.The constructed ratiometric fluorescent probe provided a rapid,environmental-friendly,reliable,and efficient platform for measuring trace Hg^(2+)in environmental field.

关键词： blue carbon dots Red carbon dots Electron transfer Hg^(2+) Eco-friendliness

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren Yu Guoshu Gao Yumeng Zhao xiongfu Zhang Guodong liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024 State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. by optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

Impulsive thrust strategy for orbital pursuit-evasion games based on impulse-like constraint

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Chinese Journal of Aeronautics 2025年第1期38卷 520-536页

作者： Hongbo WANG Yao ZHANG Hao liu Kunpeng ZHANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100094China

This paper proposes a novel impulsive thrust strategy guided by optimal continuous thrust strategy to address two-player orbital pursuit-evasion game under impulsive thrust *** strategy seeks to enhance the interpretability of impulsive thrust strategy by integrating it within the framework of differential game in traditional continuous ***,this paper introduces an impulse-like constraint,with periodical changes in thrust amplitude,to characterize the impulsive thrust ***,the game with the impulse-like constraint is converted into the two-point boundary value problem,which is solved by the combined shooting and deep learning method proposed in this *** learning and numerical optimization are employed to obtain the guesses for unknown terminal adjoint variables and the game terminal ***,the accurate values are solved by the shooting method to yield the optimal continuous thrust strategy with the impulse-like ***,the shooting method is iteratively employed at each impulse decision moment to derive the impulsive thrust strategy guided by the optimal continuous thrust *** examples demonstrate the convergence of the combined shooting and deep learning method,even if the strongly nonlinear impulse-like constraint is *** effect of the impulsive thrust strategy guided by the optimal continuous thrust strategy is also discussed.

关键词： Orbital pursuit-evasion game Differential game Impulsive thrust Deep learning Shooting method

A quantum-search-based multi-classifier for image recognition

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 17-27页

作者： Lu liu xingyu Wu Lufan Zhang Chuan Wang School of Artificial Intelligence Beijing Normal UniversityBeijing 100875China Applied Optics beijing Area Major Laboratory Beijing Normal UniversityBeijing 100875China

The multi-class classification of images is a pivotal challenge within the realm of image *** the volume of visual data continues to expand,there is a burgeoning interest in harnessing the unique capabilities of quantum computation to augment the efficiency of classification ***,many existing methods for training quantum image multi-classifiers parallel classical machine learning techniques,where the requisite circuit measurements increase linearly with the volume of training *** work introduces a novel approach for training a quantum image multi-classifier based on the quantum search *** have meticulously conducted rigorous experiments on a handwritten digit dataset,a classic benchmark in the *** results have been meticulously compared with previous works,and the comparative analysis not only validates the efficiency of our proposed approach,requiring only O(N/b)measurements during training,but also highlights a significant quadratic speedup of the algorithm.

关键词： quantum computation image recognition quantum search algorithm

Deep view of composite SNR CTA1 with LHAASO in γ-rays up to 300 TeV

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Zhen Cao F.Aharonian Axikegu Y.x.bai Y.W.bao D.bastieri x.J.bi Y.J.bi W.bian A.V.bukevich Q.Cao W.Y.Cao Zhe Cao J.Chang J.F.Chang A.M.Chen E.S.Chen H.x.Chen Liang Chen Lin Chen Long Chen M.J.Chen M.L.Chen Q.H.Chen S.Chen S.H.Chen S.Z.Chen T.L.Chen Y.Chen N.Cheng Y.D.Cheng M.C.Chu M.Y.Cui S.W.Cui x.H.Cui Y.D.Cui b.Z.Dai H.L.Dai Z.G.Dai Danzengluobu x.Q.Dong K.K.Duan J.H.Fan Y.Z.Fan J.Fang J.H.Fang K.Fang C.F.Feng H.Feng L.Feng S.H.Feng x.T.Feng Y.Feng Y.L.Feng S.Gabici b.Gao C.D.Gao Q.Gao W.Gao W.K.Gao M.M.Ge T.T.Ge L.S.Geng G.Giacinti G.H.Gong Q.b.Gou M.H.Gu F.L.Guo J.Guo x.L.Guo Y.Q.Guo Y.Y.Guo Y.A.Han O.A.Hannuksela M.Hasan H.H.He H.N.He J.Y.He Y.He Y.K.Hor b.W.Hou C.Hou x.Hou H.b.Hu Q.Hu S.C.Hu C.Huang D.H.Huang T.Q.Huang W.J.Huang x.T.Huang x.Y.Huang Y.Huang Y.Y.Huang x.L.Ji H.Y.Jia K.Jia H.b.Jiang K.Jiang x.W.Jiang Z.J.Jiang M.Jin M.M.Kang I.Karpikov D.Khangulyan D.Kuleshov K.Kurinov b.b.Li C.M.Li Cheng Li Cong Li D.Li F.Li H.b.Li H.C.Li Jian Li Jie Li K.Li S.D.Li W.L.Li W.L.Li x.R.Li xin Li Y.Z.Li Zhe Li Zhuo Li E.W.Liang Y.F.Liang S.J.Lin b.liu C.liu D.liu D.b.liu H.liu H.D.liu J.liu J.L.liu M.Y.liu R.Y.liu S.M.liu W.liu Y.liu Y.N.liu Q.Luo Y.Luo H.K.Lv b.Q.Ma L.L.Ma x.H.Ma J.R.Mao Z.Min W.Mitthumsiri H.J.Mu Y.C.Nan A.Neronov K.C.Y.Ng L.J.Ou P.Pattarakijwanich Z.Y.Pei J.C.Qi M.Y.Qi b.Q.Qiao J.J.Qin A.Raza D.Ruffolo A.Sáiz M.Saeed D.Semikoz L.Shao O.Shchegolev x.D.Sheng F.W.Shu H.C.Song Yu.V.Stenkin V.Stepanov Y.Su D.x.Sun Q.N.Sun x.N.Sun Z.b.Sun J.Takata P.H.T.Tam Q.W.Tang R.Tang Z.b.Tang W.W.Tian L.H.Wan C.Wang C.b.Wang G.W.Wang H.G.Wang H.H.Wang J.C.Wang Kai Wang Kai Wang L.P.Wang L.Y.Wang P.H.Wang R.Wang W.Wang x.G.Wang x.Y.Wang Y.Wang Y.D.Wang Y.J.Wang Z.H.Wang Z.x.Wang Zhen Wang Zheng Wang D.M.Wei J.J.Wei Y.J.Wei T.Wen C.Y.Wu H.R.Wu Q.W.Wu S.Wu x.F.Wu Y.S.Wu S.Q.xi J.xia G.M.xiang D.x.xiao G.xiao Y.L.xin Y.xing D.R.xiong Z.xiong D.L.xu R.F.xu R.x.xu W.L.xu L.xue D.H.Yan J.Z.Yan T.Yan C.W.Yang C.Y.Yang F.Yang F.F.Yang L.L.Yang M.J.Yang R.Z.Yang W.x.Yang Y.H.Yao Z.G.Yao L.Q.Yin N.Yin x.H.You Z.Y.You Y.H Southwest Jiaotong University School of Astronomy and Space Science Nanjing University Center for Astrophysics Guangzhou University Tsung-Dao Lee Institute & School of Physics and Astronomy Shanghai Jiao Tong University Institute for Nuclear Research of Russian Academy of Sciences Hebei Normal University University of Science and Technology of China LHAASO Collaboration State Key Laboratory of Particle Detection and Electronics Key Laboratory of Dark Matter and Space Astronomy & Key Laboratory of Radio Astronomy Purple Mountain Observatory Chinese Academy of Sciences Research Center for Astronomical Computing Zhejiang Laboratory Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Key Laboratory of Particle Astrophysics & Experimental Physics Division & Computing Center Yunnan University Key Laboratory of Cosmic Rays (Tibet University) Ministry of Education Department of Physics The Chinese University of Hong Kong Key Laboratory of Radio Astronomy and Technology National Astronomical Observatories Chinese Academy of Sciences School of Physics and Astronomy (Zhuhai) & School of Physics (Guangzhou) & Sino-French Institute of Nuclear Engineering and Technology (Zhuhai) Sun Yat-sen University Institute of High Energy Physics Institute of Frontier and Interdisciplinary Science Shandong University APC Université Paris Cité CNRS/IN2P3 CEA/IRFU Observatoire de Paris Department of Engineering Physics & Department of Astronomy Tsinghua University School of Physics and Microelectronics Chinese Academy of Sciences Zhengzhou University Yunnan Observatories Chinese Academy of Sciences China Center of Advanced Science and Technology College of Physics Sichuan University School of Physics Peking University Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and Technology University of Chinese Academy of Sciences Guangxi University Department of Physics Faculty of Science Mahidol University Moscow Institute

The ultra-high-energy（UHE） gamma-ray source 1LHAASO J0007+7303u is positionally associated with the composite SNR CTA1 that is located at high Galactic Latitude b ≈ 10.5°. This provides a rare opportunity to spatially resolve the component of the pulsar wind nebula（PWN） and supernova remnant（SNR） at UHE. This paper conducted a dedicated data analysis of 1LHAASO J0007+7303u using the data collected from December 2019 to July 2023. This source is well detected with significances of 21σ and 17σ at 8-100 TeV and >100 TeV, respectively. The corresponding extensions are determined to be 0.23°±0.03°and 0.17°±0.03°. The emission is proposed to originate from the relativistic electrons accelerated within the PWN of PSR J0007+7303. The energy spectrum is well described by a power-law with an exponential cutoff function dN/dE =（42.4 ± 4.1）(E/（20 TeV）)-2.31±0.11exp(-E/（110±25 TeV）) TeV-1cm-2s-1in the energy range from 8 to 300 TeV, implying a steady-state parent electron spectrum dNe/dEe∝(Ee/（100 TeV）)-3.13±0.16exp[(-Ee/（373±70 TeV）)2] at energies above ≈ 50 TeV. The cutoff energy of the electron spectrum is roughly equal to the expected current maximum energy of particles accelerated at the PWN terminal shock. Combining the x-ray and gamma-ray emission, the current space-averaged magnetic field can be limited to≈ 4.5 μG. To satisfy the multi-wavelength spectrum and the γ-ray extensions, the transport of relativistic particles within the PWN is likely dominated by the advection process under the free-expansion phase assumption.

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