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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 302-319页

作者： chang-feng li Yi-rang YUAN Huai-ling SONG School of Economics Shandong UniversityJinan 250100China Institute of Mathematics Shandong UniversityJinan 250100China College of Mathematics and Econometrics Hunan UniversityChangsha 410082China

In this paper,the authors discuss a three-dimensional problem of the semiconductor device type involved its mathematical description,numerical simulation and theoretical *** important factors,heat and magnetic influences are *** mathematical model is formulated by four nonlinear partial differential equations(PDEs),determining four major physical *** influences of magnetic fields are supposed to be weak,and the strength is parallel to the *** elliptic equation is treated by a block-centered method,and the law of conservation is *** computational accuracy is improved one *** equations are convection-dominated,thus are approximated by upwind block-centered *** difference can eliminate numerical dispersion and nonphysical *** diffusion is approximated by the block-centered difference,while the convection term is treated by upwind ***,the unknowns and adjoint functions are computed at the same *** characters play important roles in numerical computations of conductor device *** the theories of priori analysis such as energy estimates,the principle of duality and mathematical inductions,an optimal estimates result is *** a composite numerical method is shown for solving this problem.

关键词： three-dimensional conductor device problem with heat and magnetic influences upwind blockcentered differences elemental conservation of mass numerical analysis

Polarity-controllable magnetic skyrmion filter

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Chinese Physics B 2024年第10期33卷 400-404页

作者： Xiao-lin Ai Hui-Ting li Xue-feng Zhang chang-feng li Je-Ho Shim Xiao-Ping Ma Hong-Guang Piao Hubei Engineering Research Center of Weak Magnetic-Field Detection College of ScienceChina Three Gorges UniversityYichang 443002China Department of Physics College of ScienceYanbian UniversityYanji 133002China

The skyrmion generator is one of the indispensable components for the future functional skyrmion devices,but the process of generating skyrmion cannot avoid mixing with other magnetic textures,such as skyrmionium and nested skyrmion *** mixed magnetic textures will inevitably lead to the blockage of skyrmion transport and even the distortion of data ***,the design of an efficient skyrmion filter is of great significance for the development of skyrmion-based spintronic *** this work,a skyrmion filter scheme is proposed,and the high-efficiency filtering function is demonstrated by micromagnetic *** results show that the filtering effect of the scheme depends on the structure geometry and the spin current density that drives the *** on this scheme,the polarity of the filtered skyrmion can be controlled by switching the magnetization state at the output end,and the“cloning”of the skyrmion can be realized by geometric optimization of the *** believe that in the near future,the skyrmion filter will become one of the important components of skyrmion-based spintronic devices in the future.

关键词： spintronics skyrmions skyrmion filter skyrmion polarity skyrmion clone

Determination of L-phenylalanine by cucurbit[7]uril sensitized fluorescence quenching method

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Chinese Chemical Letters 2011年第7期22卷 851-854页

作者： chang feng li li Ming Du Hao Wu Ying Xia chang Analytical and Testing Center Shanxi Normal University Linfen 041004 China School of Chemistry and Materials Science Shanxi Normal University Linfen 041004 China

The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In the presence of CB [7], the fluorescence of PAL was quenched by LPA which can be employed to detect LPA. Under the optimal conditions, a linear range 3.63 ×10^-8- 9.68 ×10^-6 mol/L and a detection limit 1.27 ×10^-8 mol/L of LPA were obtained. The relative standard deviation （R.S.D） was 1.8% obtained from a series of 11 standards each containing 6.05 ×10^-6 mol/L of LPA. This paper also discusses the mechanism of fluorescence indicator probe.

关键词： L-phenylalanine Palmatine hydrochloride Cucurbituril Fluorescent probe

An Upwind Mixed Finite Volume Element-fractional Step Method and Convergence Analysis for Three-dimensional Compressible Contamination Treatment from Nuclear Waste

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应用数学学报:英文版 2023年第4期39卷 808-829页

In this paper the authors discuss a numerical simulation problem of three-dimensional compressible contamination treatment from nuclear waste. The mathematical model, a nonlinear convection-diffusion system of four PDEs, determines four major physical unknowns: the pressure, the concentrations of brine and radionuclide, and the temperature. The pressure is solved by a conservative mixed finite volume element method, and the computational accuracy is improved for Darcy velocity. Other unknowns are computed by a composite scheme of upwind approximation and mixed finite volume element. Numerical dispersion and nonphysical oscillation are eliminated, and the convection-dominated diffusion problems are solved well with high order computational accuracy. The mixed finite volume element is conservative locally, and get the objective functions and their adjoint vector functions simultaneously. The conservation nature is an important character in numerical simulation of underground fluid. Fractional step difference is introduced to solve the concentrations of radionuclide factors, and the computational work is shortened significantly by decomposing a three-dimensional problem into three successive one-dimensional problems. By the theory and technique of a priori estimates of differential equations, we derive an optimal order estimates in L2norm. Finally, numerical examples show the effectiveness and practicability for some actual problems.

关键词： compressible nuclear waste contamination in porous media upwind mixed finite volume elementfractional step conservation of mass and energy convergence analysis numerical example

A Mixed-finite Volume Element Coupled with the Method of Characteristic Fractional Step Difference for Simulating Transient Behavior of Semiconductor Device of Heat Conductor And Its Numerical Analysis

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 1053-1072页

作者： Yi-rang YUAN Qing YANG chang-feng li Tong-jun SUN Institute of Mathematics Shandong University Jinan 250100 China School of Mathematical Sciences Shandong Normal University Jinan 250014 China School of Economics Shandong University Jinan 250100 China

The mathematical system is formulated by four partial differential equations combined with initial- boundary value conditions to describe transient behavior of three-dimensional semiconductor device with heat conduction. The first equation of an elliptic type is defined with respect to the electric potential, the successive two equations of convection dominated diffusion type are given to define the electron concentration and the hole concentration, and the fourth equation of heat conductor is for the temperature. The electric potential appears in the equations of electron concentration, hole concentration and the temperature in the formation of the intensity. A mass conservative numerical approximation of the electric potential is presented by using the mixed finite volume element, and the accuracy of computation of the electric intensity is improved one order. The method of characteristic fractional step difference is applied to discretize the other three equations, where the hyperbolic terms are approximated by a difference quotient in the characteristics and the diffusion terms are discretized by the method of fractional step difference. The computation of three-dimensional problem works efficiently by dividing it into three one-dimensional subproblems and every subproblem is solved by the method of speedup in parallel. Using a pair of different grids （coarse partition and refined partition）, piecewise threefold quadratic interpolation, variation theory, multiplicative commutation rule of differential operators, mathematical induction and priori estimates theory and special technique of differential equations, we derive an optimal second order estimate in L2-norm. This numerical method is valuable in the simulation of semiconductor device theoretically and actually, and gives a powerful tool to solve the international problem presented by J. Douglas, Jr.

关键词： transient behavior of three-dimensional semiconductor device numerical simulation mixed finitevolume element modified characteristic fractional step difference second order estimate in L2 norm

Recent progress on the synthesis of defective UiO-66 for thermal catalysis

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Nano Research 2024年第10期17卷 8653-8670页

作者： Qing feng Caoyu Yang lin chang Guodong li Zhiyong Tang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 100049China

Zirconium terephthalate UiO-66 has aroused great interest in catalysis since it exhibits significant flexibility and compatibility for accommodating a high number of defects as well as exceptional thermal and chemical *** now,many works have focused on the modulations of the Zr6-oxo clusters in UiO-66 in terms of diverse synthesis,advanced characterizations,and their catalytic *** achieve high catalytic efficiency,it is still highly desired for rationally constructing and modulating the Zr6-oxo clusters with exposed catalytic sites and diverse microenvironments for advanced *** this review,we provide a comprehensive summary of recent progress on the synthesis of defective UiO-66,qualitative and quantitative characterizations,as well as a logical overview of heterogeneous catalytic applications over the past few ***,the outlooks for the research paradigm of defective UiO-66 are discussed.

关键词： defective UiO-66 de novo synthesis post-synthetic treatment characterization thermal catalysis

Robust chemo-mechanical stability of additives-free SiO_(2)anode realized by honeycomb nanolattice for high performance li-ion batteries

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Chinese Chemical Letters 2024年第10期35卷 442-446页

作者： Xinpin Pan Yongjian Cui Zhe Wang Bowen li Hailong Wang Jian Hao feng li Jing li Advanced Energy Storage Materials Lab School of Materials and New EnergyNingxia UniversityYinchuan 750021China School of Chemistry and Chemical Engineering Ningxia UniversityYinchuan 750021China

Silicon-based anodes including Si,Si Oxand SiO_(2)could deliver ultra-large capacities,but degrade fast owing to huge volume change and low ***,large amounts of elastic binder and conductive additives were composited with nanosized silicon-based materials to yield reasonable cycling stability,which nevertheless not only decrease specific capacity but also induce inhomogeneous lithiation/delithiation as well as uneven stress *** nanolattice has exhibited superior mechanical properties which could be ideal structure for silicon-based anodes,but yet faces challenges in integration of chemical reactivity,conductivity and mechanical ***,we fabricate artificial SiO_(2)honeycomb nanolattice consisting of numerous nanoscale SiO_(2)cells interconnected by through-holes,and conformal coating of highly graphitic carbon on the nanolattice is achieved through in situ catalytic ***,the nanolattice is firmly bonded on Cu substrate through atomic interdiffusion irrespective of surface *** unique structure allows fast charge transportation and homogeneous lithiation/delithiation throughout the micron-meter nanolattice,which results in excellent stability and large reversible capacity over 500 cycles at 1 A/*** results highlight design and constructing artificial nanolattice can be an effective way to prevent chemo-mechanical degradation of silicon-based anode materials.

关键词： li-ion batteries Nanolattice SiO_(2)anode Stability Conductivity

Organic solar cells with D18 or derivatives offer efficiency over 19%

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Journal of Semiconductors 2024年第5期45卷 1-4页

作者： Erming feng Chujun Zhang Jianhui chang Hengyue li liming Ding Junliang Yang Hunan Key Laboratory for Super-microstructure and Ultrafast Process School of PhysicsCentral South UniversityChangsha 410083China Center for Excellence in Nanoscience Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

In recent years,organic solar cells(OSCs)have garnered significant attention due to their distinctive attributes,such as flexibility,lightweight,and solution processing,which position them as alternatives for next-generation solar technologies[1−5].Thanks to breakthroughs in materials development,the power conversion efficiency(PCE)for single-junction OSCs has already surpassed 19%[6−13].The development of photoactive materials is pivotal in enhancing the PCEs,and several reviews have provided insights into materials design[14−18].Herein,we highlight single-junction OSCs based on D18 and its derivatives[19,20].

关键词： breakthrough insight derivatives

Metallurgy and Solidification Microstructure Control of Fusion-Based Additive Manufacturing Fabricated Metallic Alloys:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 29-53页

作者： Qiang li Xing-Ran li Bai-Xin Dong Xiao-Long Zhang Shi-li Shu feng Qiu Lai-chang Zhang Zhi-Hui Zhang Key Laboratory of Bionic Engineering(Ministry of Education) and College of Bionic Science and EngineeringJilin UniversityChangchun130022China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China Key Laboratory of Automobile Materials Ministry of Education and Department of Materials Science and EngineeringJilin UniversityChangchun130025China School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130025China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

The metal-based additive manufacturing(AM),also referred to as metal 3D printing,has drawn particular interest because it enables direct creation,aided by computationally-directed path design,of intricate components with site-specific compositions and geometrical requirements as well as low buy-to-fly *** the last two decades,the objective of this revolutionary technology has been shifting from only“rapid prototyping”to advanced manufacturing of special high-end products or devices,which,in many aspects,outperform conventional manufacturing *** fusion-based AM,significant progress has been achieved in understanding the processing window of macroscopic scales,non-equilibrium metallurgy of mesoscale scales,and grain evolution of microscopic *** the versatile capacity of AM facilitates new avenues for discovering advanced materials and structures,their potential has still not been fully *** the unique non-equilibrium solidification during the AM process,coarse columnar grains with strong textures are usually developed along the build direction,which downgrades the mechanical *** push the limits of this digital manufacturing,this review attempts to provide in-depth and comprehensive overviews of the recent progress in understanding the evolution and control of the as-built microstructure that has been made recently and the challenges encountered during the AM process.

关键词： Additive manufacturing Temperature field Microstructure control Nanoparticles Functionally graded materials

Characteristic fractional step finite difference method for nonlinear section coupled system

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Applied Mathematics and Mechanics(English Edition) 2014年第10期35卷 1311-1330页

作者：袁益让李长峰孙同军刘允欣 Institute of Mathematics Shandong University School of Economics Shandong University

For the section coupled system of multilayer dynamics of fluids in porous media, a parallel scheme modified by the characteristic finite difference fractional steps is proposed for a complete point set consisting of coarse and fine partitions. Some tech- niques, such as calculus of variations, energy method, twofold-quadratic interpolation of product type, multiplicative commutation law of difference operators, decomposition of high order difference operators, and prior estimates, are used in theoretical analysis. Optimal order estimates in 12 norm are derived to show accuracy of the second order approximation solutions. These methods have been used to simulate the problems of migration-accumulation of oil resources.

关键词： three-dimensional section coupled system complete nonlinear equation,characteristic fractional step convergence numerical simulation