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Three-dimensional magnetization reconstruction from electron optical phase images with physical constraints

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Science China(Physics,Mechanics & Astronomy) 2024年第11期Mechanics & Astronomy) .卷 126-136页

作者： Boyao Lyu Shihua Zhao yibo Zhang Weiwei Wang Fengshan Zheng Rafal E.Dunin-borkowski Jiadong Zang Haifeng Du Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices High Magnetic Field LaboratoryHefei Institutes of Physical Science Chinese Academy of Sciences Science Island Branch Graduate School of University of Science and Technology of China Department of Physics and Astronomy University of New Hampshire Department of Physics The City College of New York Physics Program Graduate Center of the City University of New York Department of Chemistry University of New Hampshire Institutes of Physical Science and Information Technology Anhui University Spin-X Institute Center for Electron Microscopy School of Physics and OptoelectronicsState Key Laboratory of Luminescent Materials and DevicesGuangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsSouth China University of Technology Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons Forschungszentrum Jülich

The ability to characterize three-dimensional(3D) magnetization distributions in nanoscale magnetic materials and devices is essential to fully understand their static and dynamic magnetic properties. Phase contrast techniques in the transmission electron microscope(TEM), such as electron holography and electron ptychography, can be used to record two-dimensional(2D) projections of the in-plane magnetic induction of 3D nanoscale objects. Although the 3D magnetic induction can in principle be reconstructed from one or more tilt series of such 2D projections, conventional tomographic reconstruction algorithms do not recover the 3D magnetization within a sample directly. Here, we use simulations to describe the basis of an improved model-based algorithm for the tomographic reconstruction of a 3D magnetization distribution from one or more tilt series of electron optical phase images recorded in the TEM. The algorithm allows a wide range of physical constraints, including a priori information about the sample geometry and magnetic parameters, to be specified. It also makes use of minimization of the micromagnetic energy in the loss function. We demonstrate the reconstruction of the 3D magnetization of a localized magnetic soliton — a hopfion ring — and discuss the influence of noise, choice of magnetic constants, maximum tilt angle and number of tilt axes on the result. The algorithm can in principle be adapted for other magnetic contrast imaging techniques in the TEM, as well as for other magnetic characterization techniques, such as those based on X-rays or neutrons.

关键词： three-dimensional magnetization vector field tomography differentiable programming electron holography micromagnetism

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Ren-integrable and ren-symmetric integrable systems

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Communications in Theoretical Physics 2024年第3期76卷 62-69页

作者： S y Lou School of Physical Science and Technology Ningbo UniversityNingbo315211China

A new type of symmetry,ren-symmetry,describing anyon physics and corresponding topological physics,is ***-symmetry is a generalization of super-symmetry which is widely applied in super-symmetric physics such as super-symmetric quantum mechanics,super-symmetric gravity,super-symmetric string theory,super-symmetric integrable systems and so *** and Grassmann numbers are,in some sense,dual conceptions,and it turns out that these conceptions coincide for the ren situation,that is,a similar conception of ren-number(R-number)is devised for *** particular,some basic results of the R-number and ren-symmetry are exposed which allow one to derive,in principle,some new types of integrable systems including ren-integrable models and ren-symmetric integrable *** examples of ren-integrable KdV-type systems and ren-symmetric KdV equations are explicitly given.

关键词： symmetries integrable systems anyon physics extended supersymmetry ren-symmetry

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Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed Sintering and Post Treatment

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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

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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Journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.y.Huang Z.yang S.y.yang Z.H.Dai y.J.Liu J.H.Liao G.y.Zhong Z.J.Xie y.P.Fang S.S.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

A perspective on age-related changes in cell environment and risk of neurodegenerative diseases

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Neural Regeneration Research 2024年第4期19卷 719-720页

作者： Alice y.Liu Department of Cell Biology and Neuroscience Rutgers State University of New JerseyPiscatawayNJUSA

“Age-related neurodegenerative disease”underscores human age as the primary risk factor for disease development:Alzheimer’s,Parkinson’s,and Huntington’s disease(HD)as *** for the age-dependent delay in disease manifestation,in particular for autosomal dominant forms of the disease,and the underlying cause(s)of specific neuron dysfunction and death to manifest as memory loss,anxiety,depression,and agitation in disease subjects remain *** are interested in understanding age-related changes in cell environment that can modulate the structure,function,aggregation.

关键词： Huntington Alzheimer death

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Supposition of graphene stacks to estimate the contact resistance and conductivity of nanocomposites

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 663-676页

作者： y.ZARE M.T.MUNIR G.J.WENG K.y.RHEE Biomaterials and Tissue Engineering Research Group Department of Interdisciplinary TechnologiesBreast Cancer Research CenterMotamed Cancer InstituteTehran ***Iran College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait Department of Mechanical and Aerospace Engineering Rutgers UniversityNew BrunswickNJ 08903U.S.A. Department of Mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 446701Republic of Korea

In this study,the effects of stacked nanosheets and the surrounding interphase zone on the resistance of the contact region between nanosheets and the tunneling conductivity of samples are evaluated with developed equations superior to those previously *** contact resistance and nanocomposite conductivity are modeled by several influencing factors,including stack properties,interphase depth,tunneling size,and contact *** developed model's accuracy is verified through numerous experimental *** further validate the models and establish correlations between parameters,the effects of all the variables on contact resistance and nanocomposite conductivity are ***,the contact resistance is primarily dependent on the polymer tunnel resistivity,contact area,and tunneling *** dimensions of the graphene nanosheets significantly influence the conductivity,which ranges from 0 S/m to90 S/*** increased number of nanosheets in stacks and a larger gap between them enhance the nanocomposite's ***,the thicker interphase and smaller tunneling size can lead to higher sample conductivity due to their optimistic effects on the percolation threshold and network efficacy.

关键词： graphene polymer composite stacked nanosheet tunneling conductivity contact resistance interphase

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A Collocation Technique via Pell-Lucas Polynomials to Solve Fractional Differential EquationModel for HIV/AIDS with Treatment Compartment

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 281-310页

作者： Gamze yıldırım Suayip yüzbası Department of Mathematics Faculty of ScienceAkdeniz UniversityAntalya07058Turkey Department of Mathematics Faculty of Basic ScienceGebze Technical UniversityKocaeli41400Turkey Department of Mathematics Faculty of ScienceBartın UniversityBartın74100Turkey

In this study,a numerical method based on the Pell-Lucas polynomials(PLPs)is developed to solve the fractional order HIV/AIDS epidemic model with a treatment *** HIV/AIDS mathematical model with a treatment compartment is divided into five classes,namely,susceptible patients(S),HIV-positive individuals(I),individuals with full-blown AIDS but not receiving ARV treatment(A),individuals being treated(T),and individuals who have changed their sexual habits sufficiently(R).According to the method,by utilizing the PLPs and the collocation points,we convert the fractional order HIV/AIDS epidemic model with a treatment compartment into a nonlinear system of the algebraic ***,the error analysis is presented for the Pell-Lucas approximation *** aim of this study is to observe the behavior of five populations after 200 days when drug treatment is applied to HIV-infectious and full-blown AIDS *** demonstrate the usefulness of this method,the applications are made on the numerical example with the help of *** addition,four cases of the fractional order derivative(p=1,p=0.95,p=0.9,p=0.85)are examined in the range[0,200].Owing to applications,we figured out that the outcomes have quite decent ***,we understand that the errors decrease when the value of N *** figures in this study are created in *** outcomes indicate that the presented method is reasonably sufficient and correct.

关键词： Collocation method fractional differential equations HIV/AIDS epidemic model Pell-Lucas polynomials

Decomposition solutions and Bäcklund transformations of the B-type and C-type Kadomtsev-Petviashvili equations

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Communications in Theoretical Physics 2024年第6期76卷 34-44页

作者： Xiazhi Hao S y Lou College of Science Zhejiang University of TechnologyHangzhou 310014China School of Physical Science and Technology Ningbo UniversityNingbo 315211China

This paper introduces a modified formal variable separation approach,showcasing a systematic and notably straightforward methodology for analyzing the B-type Kadomtsev-Petviashvili(BKP)*** the application of this approach,we successfully ascertain decomposition solutions,Bäcklund transformations,the Lax pair,and the linear superposition solution associated with the aforementioned ***,we expand the utilization of this technique to the C-type Kadomtsev-Petviashvili(CKP)equation,leading to the derivation of decomposition solutions,Bäcklund transformations,and the Lax pair specific to this *** results obtained not only underscore the efficacy of the proposed approach,but also highlight its potential in offering a profound comprehension of integrable behaviors in nonlinear ***,this approach demonstrates an efficient framework for establishing interrelations between diverse systems.

关键词： decomposition solution Backlund transformation Lax pair linear superposition solution

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： S.W.Wi y.S.Lee Department of Physics and Integrative Institute of Basic Sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence Sensitizer Rare earths