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Fourier transform of anisotropic mixed-norm Hardy spaces

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Frontiers of Mathematics in China 2021年第1期16卷 119-139页

作者： Long HUANG der-chen chang Dachun YANG Laboratory of Mathematics and Complex Systems(Ministry of Education of China) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875China Department of Mathematics and Statistics Georgetown UniversityWashingtonDC 20057USA Graduate Institute of Business Adminstration College of ManagementFu Jen Catholic UniversityNew Teipei City 242China

Let a:=(a1,…,an)∈[1,∞)n,p:=(p1,…,pn)∈(0,1]n,Hpa(R^(n))be the anisotropic mixed-norm Hardy space associated with adefined via the radial maximal function,and let f belong to the Hardy space Hpa(R^(n)).In this article,we show that the Fourier transform fcoincides with a continuous function g onℝn in the sense of tempered distributions and,moreover,this continuous function g,multiplied by a step function associated with a,can be pointwisely controlled by a constant multiple of the Hardy space norm of *** proofs are achieved via the known atomic characterization of Hpa(R^(n))and the establishment of two uniform estimates on anisotropic mixed-norm *** applications,we also conclude a higher order convergence of the continuous function gat the ***,a variant of the Hardy-Littlewood inequality in the anisotropic mixed-norm Hardy space setting is also *** these results are a natural generalization of the well-known corresponding conclusions of the classical Hardy spaces Hp(R^(n))with p∈0,1],and are even new for isotropic mixed-norm Hardy spaces on∈n.

关键词： Anisotropic(mixed-norm)Hardy space Fourier transform Hardy-Littlewood inequality

On the CR Poincaré–Lelong Equation, Yamabe Steady Solitons and Structures of Complete Noncompact Sasakian Manifolds

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Acta Mathematica Sinica,English Series 2018年第8期34卷 1313-1344页

作者： der chen chang Shu cheng chang Ying Bo HAN Chien LIN Department of Mathematics and Statistics Georgetown University Washington D. C. 20057 USA Graduate Institute of Applied Science and Engineering Fu Jen Catholic University Taipei 242 Taiwan China Yau Mathematical Sciences Center Tsinghua University Beijing 100084 P. R. China School of Mathematics and Statistics Xinyang Normal University Xinyang 464000 P. R. China Department of Mathematics National Tsing Hua University Hsinchu 30013 Taiwan China

In this paper, we solve the so-called CR Poincare-Lelong equation by solving the CR Poisson equation on a complete noncompact CR （2n ＋ 1）-manifold with nonegative pseudohermitian bisectional curvature tensors and vanishing torsion which is an odd dimensional counterpart of Kahler geometry. With applications of this solution plus the CR Liouvelle property, we study the structures of complete noncompact Sasakian manifolds and CR Yamabe steady solitons.

关键词： CR Poisson equation CR Poincare-Lelong equation CR Yamabe solitons

From ore to MOF: A case of MIL-100(Fe) production from iron ore concentrates

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Progress in Natural Science:Materials International 2024年第1期34卷 66-73页

作者： Miao chang Chiyao Tang Chong-chen Wang chen Zhao Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy Engineering Beijing University of Civil Engineering and Architecture

Within this work, iron ore concentrates instead of elemental iron Fe0and iron salts like Fe（NO3）3and FeCl3were selected as iron source to prepare MIL-100（Fe）(labeled as MIL-100（Fe）-ore). The corresponding synthesis cost is reduced to half of the MIL-100（Fe） produced from elemental iron and iron salts. As well, the unreacted iron ore concentrates can be easily separated from the as-prepared MIL-100（Fe）-ore by magnetic to facilitate the purification process, free of the strong acids to wash the residual iron. The as-obtained MIL-100（Fe）-ore with Langmuir surface area up to 2281.6 m2g-1displayed long-term chemical stability. Furthermore, the sorption capacity of MIL-100（Fe）-ore towards malachite green（MG） is up to 522.3 mg g-1at 25℃ and initial pH = 3.2, higher than that of MIL-100（Fe） yielded by conventional hydrothermal process. Finally, the production cost and life cycle assessment of MIL-100（Fe）-ore were compared with other traditional production procedures. The results revealed that our work greatly reduced the synthesis cost and enhanced the environmental sustainability.

关键词： Metal-organic framework Iron ore concentrates Adsorption Life cycle assessment

Spin-orbit interaction induced Casimir-Lifshitz torque between two-dimensional electron gases

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 134-142页

作者： Jia-Nan Rong Liang chen Kai chang State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Mathematics and Physics North China Electric Power UniversityBeijing 102206China School of Physics Zhejiang UniversityHangzhou 310027China College of Materials Science and Opto-electronic Technology University of Chinese Academy of SciencesBeijing 100049China

We investigate theoretically the Casimir interaction between two parallel two-dimensional electron gases(2DEGs)with Rashba and Dresselhaus spin-orbit interactions(SOIs),based on the quantum field *** derive an analytical expression for the polarization tensor and obtain the solution to the motion equation of the electromagnetic(EM)*** calculate the CasimirLifshitz torque(CLT)between two parallel 2DEGs with Rashba and Dresselhaus SOIs,which can be tuned by changing the relative strength between two *** anisotropic Casimir energy between 2DEGs caused by the interplay between the SOIs of 2DEGs offers a new origin of CLT and a new type of optoelectronic device.

关键词： Casimir torque two-dimensional electron gas spin-orbit interaction

Atomically Dispersed Ruthenium Catalysts with Open Hollow Structure for Lithium-Oxygen Batteries

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Nano-Micro Letters 2024年第2期16卷 154-164页

作者： Xin chen Yu Zhang chang chen Huinan Li Yuran Lin Ke Yu Caiyun Nan chen chen Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State ChemistryUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084People’s Republic of China Beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875People’s Republic of China

Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult decomposition of discharge products at ***,we have developed N-doped carbon anchored atomically dispersed Ru sites cathode catalyst with open hollow structure(h-RuNC)for Lithium–oxygen *** one hand,the abundance of atomically dispersed Ru sites can effectively catalyze the formation and decomposition of discharge products,thereby greatly enhancing the redox *** the other hand,the open hollow structure not only enhances the mass activity of atomically dispersed Ru sites but also improves the diffusion efficiency of catalytic ***,the excellent activity from atomically dispersed Ru sites and the enhanced diffusion from open hollow structure respectively improve the redox kinetics and cycling stability,ultimately achieving a high-performance lithium–oxygen battery.

关键词： Atomically dispersed Open hollow structure Discharge product Lithium Oxygen battery

A methodology for laser tool setters calibration and its precise mathematical model

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Chinese Journal of Aeronautics 2024年第7期37卷 564-581页

作者： Tao FANG Zixi FANG Ze Zhong chen Zhiyong chang School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China Gina Cody School of Engineering and Computer Science Concordia UniversityMontrealQuebec H3G 1M8Canada changsha Optimum CNC Corporation Changsha 410221China Institute for Aero-engine Smart Assembly of Shaanxi Province Xi’an 710072China

On-machine tool setting is a pivotal approach in achieving intelligent manufacturing,and laser tool setters have become a crucial component of smart machine *** tool setters play a crucial role in precisely measuring the dimensions of cutting tools during the part machining process,focusing on tool length and *** a measuring instrument,the positions of the laser axis of the laser tool setter need to be accurately calibrated before ***,in actual calibration scenarios,traditional calibration methods face challenges due to installation errors in the tool setter and geometric errors in the measuring *** address this issue,this study proposes a novel calibration ***,the calibration mechanism of the laser beam axis is *** on the accurate mathematical model of the laser beam and the measuring rod,and using the polygon clipping algorithm,the mathematical mechanism of the laser tool setter’s work is ***,a novel method is introduced to calculate the compensation distance between the laser beam reference point and the rod bottom center point at each moment during ***,by utilizing the kinematic chain of the tool setter calibration system,a new calibration method is developed to accurately calibrate the position of the laser beam axis in the machine tool coordinate ***,the accuracy of the calibration method is verified through simulation experiments and calibration *** method improves the calibration accuracy of the tool setter,and the mathematical model of the laser tool setter can be extended to the measurement of tools,thereby improving the precision of tool *** research significantly improves the efficient production performance of smart machine tools.

关键词： On-machine tool setting Smart machine tools Mathematical model Calibration method Laser tool sette

Aerodynamic Performance of Three Flapping Wings with Unequal Spacing in Tandem Formation

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Journal of Bionic Engineering 2024年第4期21卷 1662-1676页

作者： Min chang Ziyi Xu Zengshuang chen Li Li Xueguang Meng Unmanned System Research Institute National Key Laboratory of Unmanned Aerial Vehicle TechnologyNorthwestern Polytechnical UniversityXi’an710072People’s Republic of China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049People’s Republic of China Xi’an Aeronautics Computing Technique Research Institute Aviation Industry Corporation of ChinaXi’an710076People’s Republic of China

To better understand the aerodynamic reasons for highly organized movements of flying organisms,the three-flapping wing system in tandem formation was studied numerically in this *** from previous relevant studies on the multiple flapping wings that are equally spaced,this study emphasizes the impact of unequal spacing between individuals on the aerodynamics of each individual wing as well as the whole *** is found that swapping the distance between the first and second wing with the distance between the second wing and the rearmost wing does not affect the overall aerodynamic performance,but significantly changes the distribution of aerodynamic benefits across each *** the whole flapping cycle,three effects are at *** narrow channel effect and the downwash effect can promote and weaken the wing lift,respectively,while the wake capture effect can boost the *** also shows that these effects could be manipulated by changing the spacing between adjacent *** findings provide a novel way for flow control in tandem formation flight and are also inspiring for designing the formation flight of bionic aircraft.

关键词： Three flapping wings Unequal spacing Aerodynamic performance Tandem formation

Effect of cerium alloying on microstructure,texture and mechanical properties of magnesium during cold-rolling process

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Journal of Rare Earths 2024年第5期42卷 1001-1008,I0007页

作者： Zhen Zhang Huanhuan chen Shiju Cao Jinhua Peng Peng Guo chang Long Shan Wang chang chen Yong Wu Ji'an Huang Xiaodong Du Haigen Wei School of Materials Science and Engineering Hefei University of TechnologyHefei230009China NationalLocal Joint Research Center of Non-ferrous Metal Materials and Processing Technology Hefei230009China Laboratory of Nonferrous Metal Material and Processing Engineering of Anhui Province Hefei230009China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212003China Institute of Industry and Equipment Technology Hefei University of TechnologyHefei230009China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou341000China

Hot-extrusion and cold-rolling were conducted on Mg-Ce binary alloys to explore the effect of cerium(Ce)on microstructure,texture and mechanical properties of Mg *** addition of Ce results in significant grain refinement both in as-cast and hot-extruded *** basal texture is also weakened after extrusion and an inclined basal texture is formed with Ce *** strength and elongation of the Mg-Ce alloys are improved simultaneously due to such grain refinement and texture weakening *** cold-rolling,plenty of twins are found in the pure Mg and AZ31 plates while grains in the Mg-0.3Ce plate deform more uniformly without lamellar twin ***,Mg-0.3Ce alloys own strong and continuous strain hardening because Ce atoms and Mg-Ce precipitated phases serve as obstacles for dislocation slip.

关键词： Mg-Ce alloys Hot extrusion Cold-rolling Rare earths

Unraveling the complex roles of macrophages in obese adipose tissue:an overview

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Frontiers of Medicine 2024年第2期18卷 205-236页

作者： chang Peng Jun chen Rui Wu Haowen Jiang Jia Li Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou310000China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China University of Chinese Academy of Sciences Beijing100049China Department of Prosthodontics Shanghai Engineering Research Center of Advanced Dental Technology and MaterialsShanghai Key Laboratory of Stomatology&Shanghai Research Institute of StomatologyNational Clinical Research Center for Oral DiseasesShanghai Ninth People’s HospitalCollege of StomatologyShanghai Jiao Tong University School of MedicineShanghai200011China

Macrophages,a heterogeneous population of innate immune cells,exhibit remarkable plasticity and play pivotal roles in coordinating immune responses and maintaining tissue homeostasis within the context of metabolic *** activation of inflammatory macrophages in obese adipose tissue leads to detrimental effects,inducing insulin resistance through increased inflammation,impaired thermogenesis,and adipose tissue ***,adipose tissue macrophages also play a beneficial role in maintaining adipose tissue homeostasis by regulating angiogenesis,facilitating the clearance of dead adipocytes,and promoting mitochondrial *** the heterogeneity of macrophages in obese adipose tissue is crucial for unraveling the pathogenesis of obesity and holds significant potential for targeted therapeutic ***,the dual effects and some potential regulatory mechanisms of macrophages in adipose tissue have been elucidated using single-cell *** this review,we present a comprehensive overview of the intricate activation mechanisms and diverse functions of macrophages in adipose tissue during obesity,as well as explore the potential of drug delivery systems targeting macrophages,aiming to enhance the understanding of current regulatory mechanisms that may be potentially targeted for treating obesity or metabolic diseases.

关键词： obesity inflammation adipose tissue macrophages adipose tissue homeostasis