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Science China(Physics,Mechanics & Astronomy) 2020年第6期63卷 54-65页

作者： Yun xing JiaLing yang Institute of Solid Mechanics Beihang UniversityBeijing 100191China

Fighting crickets,one species of flightless insects optimally chosen by nature for millions of years,have evolved to fairly smooth and streamlined body *** article tries to answer the question how the insects manipulate air resistance when travelling through air after take-off without using their wings and meanwhile keep a high *** found that fighting crickets,Velarifictorus micado,performed two types of movements through air:stable and *** two types both have a high moving *** the stable type,the moving efficiency is larger than 95%.As a typical example,focusing on the stable type,we firstly predicted each component of aerodynamic drag applied on the crickets and analysed the drag contributions to the initial kinetic energy *** investigation revealed the mechanisms of the efficiently moving strategy against air resistance for the *** results show that the crickets can spin their hind legs to adjust body posture,thereby changing(increasing or decreasing)the air drag acting on the body to raise the efficiency during aerial *** work may advance the understanding of the significance of hind legs to insects’evolution and provide inspiration for future robot or micro aerial vehicle designs.

关键词： aerial movement air resistance robot designs energy dissipation

Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： Wenjing Yin Hongyin Ma yang Qu Jiaxin Ren Yingying Sun Zhen-Ni Guo Yi yang Stroke Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents

First and Second Order Asymptotics of the Spectral Risk Measure for Portfolio Loss Under Multivariate Regular Variation

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Journal of Systems Science & Complexity 2020年第5期33卷 1533-1544页

作者： xing Guodong yang Shanchao School of Mathematics and Statistics Hefei Normal UniversityHefei 230601China School of Mathematicsand Statistics Yulin Normal UniversityYulin 537000China School of Mathematics and Statistics Guangri Normnl UniversityGuilin 541004China

In the context of multivariate regular variation,the authors establish the first-order asymptotics of the spectral risk measure of portfolio ***,by the notion of second-order regular variation,the second-order asymptotics of the spectral risk measure of portfolio loss is also *** order to illustrate the derived results,a numerical example with Monte Carlo simulation is carried out.

关键词： Asymptotics multivariate regular variation regular variation second-order regular variation spectral risk measure value-at-risk

Distinct element method simulation of mechanical properties of material layer of pellet belt roasting machine

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Journal of Iron and Steel Research International 2024年第11期31卷 2633-2644页

作者： Yin-hua Tang xing-wang Li Xu Gao Tao yang Hong-ming long Jie Lei School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina Xinyu Iron and Steel Group Co. Ltd.Xinyu338000JiangxiChina Key Laboratory of Metallurgy Engineering&Resources Recycling(Anhui University of Technology) Ministry of EducationMa’anshan243002AnhuiChina

The thick layer and graded feeding technology of a belt roasting machine is an effective method for improving the production efficiency and quality index of pellet production,and a reasonable design of the mechanical structure of the layer is the basis for optimizing the heat and mass transfer performance of the *** effect and von Mises yield criterion were used to establish a simplified mathematical model describing the elastic and plastic deformation of the green pellet under the action of an external *** mechanical characteristics of extrusion,contact,and elastic-plastic deformation between green pellet particles in the material layer of the belt roasting machine were modeled using EDEM *** a green pellet size of 12 mm,as the layer height increases from 300 to 1000 mm,the maximum vertical pressure on the pellets increases from 11.64 to 24.01 N,and the porosity decreases from 27.04%to 22.01%.As the layer height increases,the contact between the green pellets becomes more intense,and the force chain structure of the layer becomes more stable;the Janssen effect is observed when the layer reaches 700 *** compressive strength of the green pellets is linearly related to the particle size,and the compressive strength increases with an increase in particle *** a layer height of 600 mm,as the particle size of the green pellets increases from 8 to 20 mm,the maximum vertical pressure increases from 7.54 to 44.16 N,and the porosity increases from 23.20%to 31.47%,while the yield per unit of the layer decreased by 12.1%.Small particles have a more stable force chain structure,larger comparative area,and higher production efficiency;however,their compressive strength is *** particles have higher compressive strength and good permeability in the layer,but the production efficiency is relatively *** actual production,a variety of factors should be integrated to optimize the feeding,and a multi-granularity graded feeding is the most ideal

关键词： Belt roasting machine Distinct element method Green pellet Thick material layer Mechanical property

Highly conductive and stable iodine doped argyrodite electrolyte for all-solid-state lithium batteries

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Journal of Energy Chemistry 2025年第1期100卷 50-58页

作者： Gaozhan Liu Jing Zhang Jing yang Jinghui Chen xingyue Xiao Xiayin Yao Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Lithium argyrodites with high ionic conductivity and low cost are considered as one of the most prospective solid electrolytes for all-solid-state lithium ***,the poor chemical stability and compatibility with lithium metal limit their ***,Li5.4PS4.4Cl1.4I0.2solid electrolyte with high ionic conductivity of 11.49 m S cm-1and improved chemical stability is synthesized by iodine *** ultra-thin Li5.4PS4.4Cl1.4I0.2membrane with thickness of 10μm can be obtained by wet coating process,exhibiting a high ionic conductivity of 2.09 mS cm-1and low areal resistance of 1.17Ω***,iodine doping could in-situ form LiI at the lithium/electrolyte interface and improve the critical current density of Li5.4PS4.4Cl1.6from 0.8 to 1.35 mA *** resultant LiCoO2/Li5.4PS4.4Cl1.4I0.2/Li battery shows excellent cycling stability at 1 C,with a reversible specific capacity of 110.1 mA h g-1and a retention of 80.5% after 1000 *** addition,the assembled LiCoO2/Li5.4PS4.4Cl1.4I0.2membrane/Li pouch cell delivers an initial discharge capacity of 110.4 mA h g-1and 80.5% capacity retention after 100 cycles.

关键词： Argyrodite electrolytes Iodine doping Ionic conductivity Stability All-solid-state lithium battery

Bandgap characteristics analysis and graded design of a novel metamaterial for flexural wave suppression

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 1-24页

作者： Fan yang Zhaoyang MA xingming GUO Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai University Shanghai Institute of Aircraft Mechanics and Control

A novel elastic metamaterial is proposed with the aim of achieving lowfrequency broad bandgaps and bandgap regulation. The band structure of the proposed metamaterial is calculated based on the Floquet-Bloch theorem, and the boundary modes of each bandgap are analyzed to understand the effects of each component of the unit cell on the bandgap formation. It is found that the metamaterials with a low elastic modulus of ligaments can generate flexural wave bandgaps below 300 Hz. Multi-frequency vibrations can be suppressed through the selective manipulation of bandgaps. The dual-graded design of metamaterials that can significantly improve the bandgap width is proposed based on parametric studies. A new way that can regulate the bandgap is revealed by studying the graded elastic modulus in the substrate. The results demonstrate that the nonlinear gradient of the elastic modulus in the substrate offers better bandgap performance. Based on these analyses, the proposed elastic metamaterials can pave the way for multi-frequency vibration control, low-frequency bandgap broadening, and bandgap tuning.

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Direct pore engineering of 2D imine covalent organic frameworks via sub-stoichiometric synthesis

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Science China Chemistry 2022年第1期65卷 190-196页

作者： Xiao yang Zhen Xie Ting Zhang Guang Zhang Ziqiang Zhao Yong Wang Guolong xing long Chen Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China

Two-dimensional covalent organic frameworks(2D COFs)bearing various topologies can be precisely designed based on the symmetry of *** pore environment can be further regulated via either pre-functionalization of the monomers or post-modification of the *** them,sub-stoichiometric synthesis is an efficient method which can mediate uncondensed functional moieties periodically arranged in the COF ***,a series of imine-linked 2D COFs with specifically decorated formyl or amino groups were selectively synthesized via sub-stoichiometric formyl *** molar ratios of the monomers directly determine the structures of the resulting COFs with periodic vertex *** COF with polar amino sites could efficiently capture CO_(2) and H_(2)*** work demonstrates tuning the stoichiometry of the monomers could facilely modulate the functions of the pore *** also provides insights into constructing novel COFs with complex structures for targeted applications.

关键词： covalent organic frameworks sub-stoichiometric periodic vertex vacancies

Hydrogen production via chemical looping reforming of coke oven gas

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Green Energy & Environment 2021年第5期6卷 678-692页

作者： Kun yang Zhenhua Gu Yanhui long Shen Lin Chunqiang Lu xing Zhu Hua Wang Kongzhai Li State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China

Coke oven gas(COG)is one of the most important by-products in steel industry,and the conversion of COG to value-added products has attracted much attention from both economic and environmental *** this work,we use the chemical looping reforming technology to produce pure H_(2) from COG.A series of La1-xSrxFeO_(3)(x?0,0.2,0.3,0.4,0.5,0.6)perovskite oxides were prepared as oxygen carriers for this *** reduction behaviors of La1-xSrxFeO_(3) perovskite by different reducing gases(H_(2),CO,CH4 and the mixed gases)are investigated to discuss the competition effect of different components in COG for reacting with the oxygen *** results show that reduction temperatures of H_(2) and CO are much lower than that of CH4,and high temperatures(>800℃)are requested for selective oxidation of methane to *** co-existence of CO and H_(2) shows weak effect on the equilibrium of methane conversion at high temperatures,but the oxidation of methane to syngas can inhibit the consumption of CO and H_(2).The doping of suitable amounts of Sr in LaFeO_(3) perovskite(e.g.,La0.5Sr0.5FeO_(3))significantly promotes the activity for selective oxidation of methane to syngas and inhibits the formation of carbon deposition,obtaining both high methane conversion in the COG oxidation step and high hydrogen yield in the water splitting *** La0.5Sr0.5FeO_(3) shows the highest methane conversion(67.82%),hydrogen yield(3.34 mmol g^(-1))and hydrogen purity(99.85%).The hydrogen yield in water splitting step is treble as high as the hydrogen consumption in reduction *** results reveal that chemical looping reforming of COG to produce pure H_(2) is feasible,and an O_(2)-assistant chemical looping reforming process can further improves the redox stability of oxygen carrier.

关键词： Coke oven gas Chemical looping reforming La1-xSrxFeO_(3) Oxygen carrier Hydrogen yield

Microstructure and phase transformation of as-cast and annealed Mg–4Zn–1Y alloy containing quasi-crystal phase

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Rare Metals 2015年第4期34卷 239-244页

作者： yang yang Kui Zhang xing-Gang Li Yong-Jun Li Ming-long Ma Guo-Liang Shi Jia-Wei Yuan State Key Laboratory for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals

By means of optical microscope （OM）, X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM） analyses, the microstructures of as-cast and heat-treated Mg--4Zn-IY （wt%） alloy containing quasi-crystal phase were studied. The microstructure of the as-cast alloy consists of a-Mg solid solution grains, intermetallic particles and eutectic phases （W-phase and 1-phase）, and huge grains with seri- ous dendritic segregation are clearly observed. After heat treatment, phase transformation and dissolution occur in the alloy and many phases remain. When the alloy was treated above 410 ~C, the eutectic phases transform into spherical shape as the I-phase turns to W-phase. After heat treatment for long time, the alloy is over burnt and the W-phase decomposes to Mg-Y binary phase.

关键词： Mg-Zn-Y alloy Heat treatment Microstructure Phase transformation Icosahedral quasi-crystal

Sex differences in aging and injured brain

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Neural Regeneration Research 2025年第10期20卷 2901-2902页

作者： Jordan N.Williamson Yuan yang University of Illinois Urbana-Champaign Grainger College of EngineeringDepartment of BioengineeringUrbanaILUSA Carle Foundation Hospital Stephenson Family Clinical Research InstituteClinical Imaging Research CenterUrbanaILUSA University of Illinois Urbana-Champaign Beckman Institute for Advanced Science and TechnologyUrbanaILUSA Northwestern University Department of Physical Therapy and Human Movement SciencesChicagoILUSA

Background:The prevalence,age of onset,and symptomatology of traumatic brain injury,stroke,and neurodegenerative diseases(such as Alzheimer’s disease(AD),Parkinson’s disease,amyotrophic lateral sclerosis,and Huntington’s disease)differ substantially between males and *** higher prevalence of these brain disorders has been attributed to females having a greater longevity compared with *** one of the greatest risk factors of acquired brain injury(such as stroke,traumatic brain injury caused by fall)and neurodegenerative disease is age.

关键词： Huntington prevalence traumatic