检索结果-南通市图书馆

Atomic-scale roles of Zn element in age-hardened AlMgSiZn alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第11期70卷 105-112页

作者： n.n.Jiao Y.X.lai S.l.chen P.Gao J.H.chen Center for High-Resolution Electron Microscopy College of Materials Science&EngineeringHunan UniversityChangsha410082China Electron Microscopy laboratory and International Center for Quantum Materials School of PhysicsPeking UniversityBeijing100871China

Adding alloying elements to improve the performances or the manufacturing processes of Al-Mg-Si alloys has l.ng been a serious issue in developing advanced automotive aluminum *** Zn element,among those promising ones,has demonstrated positive alloying effects on Al-Mg-Si ***,the atomic-scale roles of Zn in an age-hardened Al-Mg-Si-Zn alloy have not been adequately *** atomic-resolution electron microscopy,here we report the precise locations of Zn elements in all hardening precipitates involved and their alloying mechanism at the atomic scale when alloying the *** results show that Zn atoms enter all the major hardening phases to occupy specific featured atomic sites of the original elements,*** Si1 and Mg2 sites in theβ’-2 phase,and modify their crystal structures,interfacial structures and morphologies in characteristic *** is revealed that for theβ’-phase,Zn atoms occupy unique atomic sites,whereas for other phases,they demonstrate similar behaviors as other additive alloying elements such as Ag and Cu do.

关键词： Al-Mg-Si alloy Zn addition Precipitate Electron microscopy

Bioinspired Passive Tactile Sensors Enabled by Reversible Polarization of Conjugated Polymers

在线全文

学校读者我要写书评

暂无评论

nano-Micro letters 2025年第1期17卷 361-377页

作者： Feng He Sitong chen Ruili Zhou Hanyu Diao Yangyang Han Xiaodong Wu School of Mechanical Engineering Sichuan UniversityChengdu 610065People’s Republic of China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065People’s Republic of China State Key laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065People’s Republic of China

Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced *** to active sensing devices,passive piezoelectric and triboelectric tactile sensors consume less power,but lack the capability to resolve static ***,we address this issue by utilizing the unique polarization chemistry of conjugated polymers for the first time and propose a new type of bioinspired,passive,and bio-friendly tactile sensors for resolving both static and dynamic ***,to emulate the polarization process of natural sensory cells,conjugated polymers(including poly(3,4-ethyl.nedioxythiophen e):poly(styrenesulfonate),polyanil.ne,or polypyrrole)are controllably polarized into two opposite states to create artificial potential *** controllable and reversible polarization process of the conjugated polymers is fully in situ ***,a micro-structured ionic electrolyte is employed to imitate the natural ion channels and to encode external touch stimulations into the variation in potential difference *** with the currently existing tactile sensing devices,the developed tactile sensors feature distinct characteristics including fully organic composition,high sensitivity(up to 773 mV n^(−1)),ultralow power consumption(nW),as well as superior *** demonstrations,both single point tactile perception(surface texture perception and material property perception)and two-dimensional tactile recognitions(shape or profile perception)with high accuracy are successfully realized using self-defined machine learning *** tactile sensing concept innovation based on the polarization chemistry of conjugated polymers opens up a new path to create robotic tactile sensors and prosthetic electronic skins.

关键词： Passive tactile sensors Reversible polarization of conjugated polymers Tactile perception Machine learning algorithm Object recognition

Spatial transcriptomics combined with single-nucleus RnA sequencing reveals glial cell heterogeneity in the human spinal cord

在线全文

学校读者我要写书评

暂无评论

neural Regeneration Research 2025年第11期20卷 3302-3316页

作者： Yali chen Yiyong Wei Jin liu Tao Zhu cheng Zhou Donghang Zhang Department of Anesthesiology West China HospitalSichuan UniversityChengduSichuan ProvinceChina laboratory of Anesthesia and Critical Care Medicine National-Local Joint Engineering Research Center of Translational Medicine of AnesthesiologyWest China HospitalSichuan UniversityChengduSichuan ProvinceChina Department of Anesthesiology Longgang District Maternity&Child Healthcare Hospital of Shenzhen City(Longgang Maternity and Child Institute of Shantou University Medical College)ShenzhenGuangdong ProvinceChina Department of Anesthesiology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Glial cells play crucial roles in regulating physiological and pathological functions,including sensation,the response to infection and acute injury,and chronic neurodegenerative *** cells include astrocytes,microglia,and oligodendrocytes in the central.nervous system,and satellite glial cells and Schwann cells in the peripheral.nervous *** the greater understanding of glial cell types and functional heterogeneity achieved through single-cell and single-nucleus RnA sequencing in animal models,few studies have investigated the transcriptomic profiles of glial cells in the human spinal ***,we used high-throughput single-nucleus RnA sequencing and spatial transcriptomics to map the cellular and molecular heterogeneity of astrocytes,microglia,and oligodendrocytes in the human spinal *** explore the conservation and divergence across species,we compared these findings with those from *** the human spinal cord,astrocytes,microglia,and oligodendrocytes were each divided into six distinct transcriptomic *** the mouse spinal cord,astrocytes,microglia,and oligodendrocytes were divided into five,four,and five distinct transcriptomic subclusters,*** comparative results revealed substantial heterogeneity in all glial cell types between humans and ***,we detected sex differences in gene expression in human spinal cord glial ***,in all astrocyte subtypes,the levels of nEAT1 and CHI3l1 were higher in males than in females,whereas the levels of CST3 were lower in males than in *** all microglial subtypes,all differentially expressed genes were located on the sex *** addition to sex-specific gene differences,the levels of MT-nD4,MT2A,MT-ATP6,MT-CO3,MT-nD2,MT-nD3,and MT-CO_(2) in all spinal cord oligodendrocyte subtypes were higher in females than in ***,the present dataset extensively characterizes glial cell heterogeneity and offers a valuable resource for explo

关键词： astrocyte glial cell human microglia oligodendrocyte sex differentiation single-nucleus RnA sequencing spatial transcriptomics species variation spinal cord

Magneto optics and time resolved terahertz spectrocopy

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2018年第7期27卷 112-119页

作者： T Dong Z G chen n l Wang International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Exploring, manipulating, and understanding new exotic quantum phenomena in condensed-matter systems have gen- erated great interest in the scientific community. Static and time resolved optical spectroscopies after photoexcitations are important experimental tools for probing charge dynamics and quasiparticle excitations in quantum materials. In Syner- getic Extreme Condition User Facility （SECUF）, we shall construct magneto-infrared and terahertz measurement systems and develop a number of ultrafast femtosecond laser based systems, including intense near to mid-infrared pump terahertz probe. In this article, we shall describe several systems to be constructed and developed in the facilities, then present some examples explaining the application of magneto optics and time resolved spectroscopy techniques.

关键词： magneto-optics infrared spectroscopy mid-infrared pump terahertz probe

Construction of ni single-atom coordinated with doped n and S elements for mild hydrogenation of methyl acrylate to methyl propionate

在线全文

学校读者我要写书评

暂无评论

nano Research 2025年第1期18卷 217-224页

作者： Taolue Sun chen Jian Gang Wang Hui Zhao Guoliang Zhang Zengxi li Chunshan li State Key laboratory of Mesoscience and Engineering CAS Key Laboratory of Green Process and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Huizhou Institute of Green Energy and Advanced Materials Huizhou 516081China Advanced Energy Science and Technology Guangdong laboratory Huizhou 516081China

Although the nickel-based catalyst is able toexhibit comparative catalytic activity to noble metal formethyl acrylate hydrogenation,it requires strict reactioncondition,which can be improved by regulation ofcoordination *** this study,we constructed akind of ni single-atom coordinated with n and S(ni-nSC)through the pyrolysis of organic ni-based precursors at600℃.The existence and fine structure of ni single-atom were confirmed by the spherical electron microscopicobservation in combination with the X-ray absorption spectroscopy(XAS)*** addition,the catalytichydrogenation assessment suggested that the as-prepared ni-nSC catalyst exhibited higher activity and stability than theni/nSC supported catalyst prepared by incipient wetness impregnation *** remarkable catalytic activity was dueto the high dispersion and density of ni single-atom and weak adsorption energy of intermediates on these ni sites.

关键词： methyl acrylate mild hydrogenation ni single-atom coordination environment adsorption energy

FInITE ElEMEnT nUMERICAl SIMUlATIOn OF TEMPERATURE FIElD In METAl PATTERn CASTInG SYSTEM AnD "REVERSE METHOD" OF DEFInInG THE THERMAl PHYSICAl COEFFICIEnT

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English letters) 2007年第3期20卷 217-224页

作者： l. chen P.l. Wang P.n. Song J.Y. Zhang Mechanical Engineering College Tianjin University of Technology Tianjin 300191China

With the technology support of virtual reality and AnSYS software, an example on the simulation of temperature distribution of casting system during the solidification process was provided, which took the latent heat of phase change, the conditions for convection, and the interface heat transfer coefficient into consideration. The result of AnSYS was found to agree well with the test data. This research offers an unorthodox way or ＂reverse method＂ of defining the relevant thermal physical coefficient.

关键词： solidification process reverse method AnSYS software

Principal Value and Its Applications for One Type of Cauchy–FantappièIntegral and the System of Equations

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2022年第9期38卷 1537-1550页

作者： lüPing chen School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

It is known that principal value plays vital roles in the study of singular *** this paper,one type of Cauchy–Fantappièintegral with multiple indexes is *** the structure of the kernel is complexity,the Jacobian determinant included in the kernel is expanded for making clearly the expression of the ***,one differential operator is utilized for setting up relations between integrals with higher and usual *** work also concerns the convergent properties of the *** order to study Hadamard principal value and composite formula of this integral,finite and divergent parts will be estimated and *** an application,solvability of the system of integral equations with higher order singularity kernel is discussed.

关键词： Principal value Cauchy–Fantappièintegral piecewise smooth manifold differential operator system of singular integral equation

Salsol.nol as an RnA m~6A methylation inducer mediates dopaminergic neuronal death by regulating YAP1 and autophagy

在线全文

学校读者我要写书评

暂无评论

neural Regeneration Research 2025年第3期20卷 887-899页

作者： Jianan Wang Yuanyuan Ran Zihan li Tianyuan Zhao Fangfang Zhang Juan Wang Zongjian liu Xuechai chen Beijing International Science and Technology Cooperation Base for Antiviral Drugs College of Chemistry and LifeBeijing University of TechnologyBeijingChina Department of Rehabilitation Beijing Rehabilitation HospitalCapital Medical UniversityBeijingChina

Salsol.nol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinol.ne,Sal)is a catechol isoquinol.ne that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environmental toxin that causes Parkinson's ***,the mechanism by which Sal mediates dopaminergic neuronal death remains *** this study,we found that Sal significantly enhanced the global level of n~6-methyladenosine(m~6A)RnA methylation in PC12 cells,mainly by inducing the downregulation of the expression of m~6A demethylases fat mass and obesity-associated protein(FTO)and alk B homolog 5(AlKBH5).RnA sequencing analysis showed that Sal downregulated the Hippo signal.ng *** m~6A reader YTH domain-containing family protein 2(YTHDF2)promoted the degradation of m~6A-containing Yes-associated protein 1(YAP1)mRnA,which is a downstream key effector in the Hippo signal.ng ***,downregulation of YAP1 promoted autophagy,indicating that the mutual regulation between YAP1 and autophagy can lead to *** findings reveal the role of Sal on m~6A RnA methylation and suggest that Sal may act as an RnA methylation inducer mediating dopaminergic neuronal death through YAP1 and *** results provide greater insights into the neurotoxic effects of catechol isoquinol.nes compared with other studies and may be a reference for assessing the involvement of RnA methylation in the pathogenesis of Parkinson's disease.

关键词： AlKBH5 autophagy FTO Hippo pathway m~6A Parkinson's disease RnA methylation salsol.nol YAP1 YTHDF2

Extension/Compression-Controlled Complete Band Gaps in 2D Chiral Square-lattice-like Structures

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2018年第1期31卷 51-65页

作者： Y. l. Huang n. Gao W.Q. chen R.H. Bao Department of Engineering Mechanics Zhejiang University Hangzhou 310027 China State Key lab of CAD & CG Zhejiang University Hangzhou 310058 China Key laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang University Hangzhou 310027 China Soft Matter Research Center Zhejiang University Hangzhou 310027 China

Achieving tunable band gaps in a structure by external stimuli is of great importance in acoustic applications. This paper aims to investigate the tunability of band gaps in square-lattice-like elastic periodic structures that are usually not featured with notable band gaps. Endowed with chirality, the periodic structures here are able to undergo imperfection-insensitive large deformation under extension or compression. The influences of geometric parameters on band gaps are discussed via the nonl.near finite element method. It is shown that the band gaps in such structures with curved beams can be very rich and, more importantly, can be efficiently and robustly tuned by applying appropriate mechanical loadings without inducing buckl.ng. As expected, geometry plays a more significant role than material.nonl.nearity does in the evolution of band gaps. The dynamic tunability of band gaps through mechanical loading is further studied. Results show that closing, opening, and shifting of band gaps can be realized by exerting real-time global extension or compression on the structure. The proposed periodic structure with well-designed chiral symmetry can be useful in the design of particular acoustic devices.

关键词： Band gap Tunability Square-lattice-like periodic structure Chiral symmetry,large deformation