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Acta Metallurgica sinica(English Letters) 2024年第2期37卷 255-265页

作者： x.Y.Yue s.Y.Peng x.zhang C.N.He Y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China school of Materials science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACs and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability strength Electrical conductivity

An adaptive machine learning-based optimization method in the aerodynamic analysis of a finite wing under various cruise conditions

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 27-34页

作者： Zilan zhang Yu Ao shaofan Li Grace x.Gu Department of Mechanical Engineering University of CaliforniaBerkeley 94720USA Department of Engineering Peking UniversityBeijing 100871China Department of Civil and Environmental Engineering University of CaliforniaBerkeley 94720USA

Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight *** of ex.s.ing literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational *** we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise *** methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing *** has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical *** also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements.

关键词： Aerodynamic optimization Computational fluid dynamics Radial basis function Finite wing Deep learning neural network

The preface: Interplay of topological and magnetic orders in the Mn-Bi-Te family

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National science Review 2024年第2期11卷 6-7页

作者： Fu-Chun zhang Hai-Zhou Lu x.C.xie Kavli Institute for Theoretical sciences University of Chinese Academy of Sciences Department of Physics Southern University of Science and Technology (SUSTech) International Center for Quantum Materials School of Physics Peking University

The discovery and synthesis of MnBi2Te4in 2013 initially garnered little attention [1]. Yet, the revelation of its topological properties in 2019 [2–6] sparked a surge of research into the MnBiTe family. These extensive studies are primarily driven by two objectives:the realization of a high-temperature quantum anomalous Hall effect （QAHE） and the exploration of exotic phases born from the interplay of topological and magnetic orders,

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Therapy for benign rectal anastomotic stricture after surgery for colorectal cancer: A systematic review

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Laparoscopic, Endoscopic, and Robotic surgery 2024年第4期7卷 166-173页

作者： Cao G. Wu s. zhang L. zhang x. Zhou W. Department of Colorectal surgery Sir Run Run Shaw Hospital Zhejiang University School of Medicine Hangzhou 310016 China Zhejiang University school of Medicine Hangzhou 310030 China Department of General surgery Tan Tock Seng Hospital Singapore 308433 Singapore

Aim: To evaluate various treatment methods for benign rectal anastomotic stricture (As) following surgery for colorectal cancer. Method: A systematic review of the literature was conducted, focusing on studies that reported outcomes of different treatment modalities for benign As. The PubMed, Embase, scopus, China National Knowledge Infrastructure, and Cochrane Library databases were searched from January 2000 to December 2023. The inclusion criteria were studies involving human subjects, published in English, and reporting on therapeutic outcomes for benign As. Results: A total of 19 papers identified a range of therapeutic strategies, including nonoperative anastomotic dilation, endoscopic balloon dilation (EBD), transanal minimally invasive surgery (TAMIs), self-expandable metal stents (sEMs), endoscopic incision (EI) and newer techniques such as prostate resection instrumentation. Nonoperative anastomotic dilation can serve as an initial treatment for lower As. EI demonstrated promise in cases where EBD was ineffective, providing an alternative method for managing As. TAMIs and sEMs showed higher efficacy in refractory cases, with TAMIs being particularly effective for severe fibrotic or completely closed As. The use of rigid instrumentation with an electric knife for transanal incisions demonstrated precision but lacked the flexibility needed for complex procedures. Conclusion: While traditional methods such as nonoperative anastomotic dilation and EBD remain first-line treatments for benign As, advanced techniques such as EI, TAMIs, and sEMs offer promising alternatives, particularly in refractory cases. The choice of treatment should be tailored to individual patient conditions, with consideration for the technical expertise required and the potential for complications. © 2024 Zhejiang University

关键词： Colorectal cancer Rectal anastomotic stricture Therapy

Discovery of new MAx-phase-like layered ternary carbide V_(8)P_(6)C:Crystal structure,thermal expansion,and elastic properties

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Journal of Materials science & Technology 2024年第7期174卷 55-62页

作者： H.x.Chen L.sheng Z.L.zhang x.C.Wen D.L.Yang x.Y.Ye P.Q.Dai school of Materials science and Engineering Fujian University of TechnologyFuzhou 350118China Beijing synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China Fujian Provincial Key Laboratory of Advanced Materials Processing and Application Fuzhou 350118China state Key Laboratory of structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Due to the laminated structure,MAx phases and MAx-phase-like compounds possess outstanding dam-age tolerance capability with good thermal/electrical conductivity and other charming functional prop-erties,showing a bright future for structural-functional ***,a new MAx-phase-like ternary car-bide V_(8)P_(6)C with layered characteristics was *** to the alternate stacking of hexagonal-arranged M/A/x atom layers in MAx phases,V_(8)P_(6)C has a layered structure formed by a repeated stacking of the slabs consisting of V_(6)C-octahedrons and VP 6-distorted-octahedrons in three-atomic layers *** thermal expansion anisotropy was revealed,with the thermal expansion coefficients(TECs)along a-ax.s.c-ax.s.and the average value,equal toα_(a)=8.55(5)μK^(−1),α_(c)=10.23(5)μK^(−1),andα_(L)=9.14(5)μK^(−1),*** dilation along the c-ax.s.was mainly dominated by out-plane V-P bonds be-tween layered *** to the pressure-dependent lattice parameters,the polycrystalline bulk modulus(B_(0)=185(9)GPa)and high compressibility anisotropy factor(B_(a)/B_(c)=1.64)was ***-while,the second-order elastic constants were calculated,and the elastic moduli,E=303 GPa,B=198 GPa,G=122 GPa,andν=0.246,were *** the weak connection between layer slabs by out-plane V1-P bond was revealed by the bond stiffness model,with a bond stiffness close to the M-A bond in MAx ***,good damage tolerance capability was predicted according to Paugh’s ratio(G/B=0.616)and Cauchy pressure(P_(a)=0 GPa,P_(c)=-7.5 GPa),even better than those of typical MAx *** discovery of V_(8)P_(6)C provides a new member of MAx-phase-like damage-tolerant ceramic with relatively low density,moderate thermal expansion,and anisotropic compressibility,and the unique lay-ered structure is inspiring for exploring new layered ternary ceramics.

关键词： New ternary carbide MAx phase Thermal expansion Elastic constants Anisotropy

Cognition on oxidation behavior of Ni-based superalloy GH4742 when exposed to water vapor

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Journal of Materials science & Technology 2024年第7期174卷 15-22页

作者： H.xu s.F.Yang E.H.Wang C.Y.Guo Y.s.Liu x.M.Hou Y.L.zhang state Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The oxidation behavior of Ni-based superalloy GH4742 exposed to water vapor was investigated at 900-1100℃for 50 h in Ar+20%H_(2)O,with Ar+20%O_(2)included for *** presence of H_(2)O is adverse to formation of continuous Cr_(2)O_(3)oxide layer but contributes to generation of big *** on this,Ni^(2+)and Co^(2+)are more easily to diffuse towards the outermost oxide layer(OOL),forming non-protective Ni-and Co-rich oxides with high *** leads to a higher weight gain in Ar+20%H_(2)O than that in Ar+20%O_(2).At elevated temperatures,the spallation of oxide scale occurs while the consumption of Cr is reduced in Ar+20%H_(2)O,and the contents of Ni-and Co-rich oxides at this moment are reduced in the *** oxidation mechanism was also discussed.

关键词： GH4742 superalloy H_(2)O Diffusion Oxidation Mechanism

Digital Image steganographer Identification: A Comprehensive survey

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Computers, Materials and Continua 2024年第1期81卷 105-131页

作者： zhang Q. zhang Y. Ma Y. Liu Y. Luo x. Information Engineering University Zhengzhou 450001 China Key Laboratory of Cyberspace situation Awareness of Henan Province Zhengzhou 450001 China College of Computer and Information Engineering Henan Normal University Xinxiang 453007 China

The rapid development of the internet and digital media has provided convenience while also posing a potential risk of steganography abuse. Identifying steganographer is essential in tracing secret information origins and preventing illicit covert communication online. Accurately discerning a steganographer from many normal users is challenging due to various factors, such as the complexity in obtaining the steganography algorithm, extracting highly separability features, and modeling the cover data. After extensive exploration, several methods have been proposed for steganographer identification. This paper presents a survey of ex.s.ing studies. Firstly, we provide a concise introduction to the research background and outline the issue of steganographer identification. secondly, we present fundamental concepts and techniques that establish a general framework for identifying steganographers. Within this framework, state-of-the-art methods are summarized from five key aspects: data acquisition, feature extraction, feature optimization, identification paradigm, and performance evaluation. Furthermore, theoretical and experimental analyses examine the advantages and limitations of these ex.s.ing methods. Finally, the survey highlights outstanding issues in image steganographer identification that deserve further research. © 2024 The Authors. Published by Tech science Press.

关键词： covert communication Information hiding steganalysis steganographer identification steganography survey

Distributed field mapping for mobile sensor teams using a derivative‐free optimisation algorithm

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IET Cyber-systems and Robotics 2024年第2期6卷 20-34页

作者： Tony x.Lin Jia Guo said Al-Abri Fumin zhang Fumin zhang31school of Electrical&Computer Engineering Georgia Institute of TechnologyAtlantaGeorgiaUSA College of Engineering Sultan Qaboos UniversityMuscatOman Department of Electronic&Computer Engineering Hong Kong University of Science and TechnologyHong KongChina

The authors propose a distributed field mapping algorithm that drives a team of robots to explore and learn an unknown scalar field using a Gaussian Process(GP).The authors’strategy arises by balancing exploration objectives between areas of high error and high *** computing high error regions is impossible since the scalar field is unknown,a bio-inspired approach known as speeding-Up and slowing-Down is leveraged to track the gradient of the GP *** approach achieves global field-learning convergence and is shown to be resistant to poor hyperparameter tuning of the *** approach is validated in simulations and experiments using 2D wheeled robots and 2D flying mini-ature autonomous blimps.

关键词： environment sensing multi-robot systems

Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.x.Wang x.L.Zhu s.M.Weng P.Li x.F.Li H.Ai H.R.Pan Z.M.sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFsA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China state key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(THz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or THz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or THz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and THz spectral ranges.

关键词： laser ultrashort photon

In situ TEM investigation of electron irradiation and aging-induced high-density nanoprecipitates in an Mg-10Gd-3Y-1Zn-0.5Zr alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1841-1853页

作者： M.Lv H.L.Ge Q.Q.Jin x.H.shao Y.T.Zhou B.zhang x.L.Ma shenyang National Laboratory for Materials science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China school of Materials science and Engineering University of Science and Technology of ChinaShenyang 110016China Materials science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density precipitates in an Mg-10Gd-3Y-1Zn-0.5Zr(GWZ1031K,wt.%)alloy to improve the *** results show that the hardness of the Mg alloy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximately 64% higher than that of the samples before being *** is mainly attributed to γ'precipitates on the basal plane after irradiation and the high-density nanoscale β'precipitates on the prismatic plane after aging,which should be closely related to the irradiation-induced homogenous *** latter plays a key role in precipitation *** result paves a way to improve the mechanical properties of metallic materials by tailoring the precipitation through irradiation and aging.

关键词： Mg alloy Electron beam irradiation Hardening Precipitates In-situ TEM