检索结果-南通市图书馆

Simultaneous enhancement of mechanical and shape memory properties by heat-treatment homogenization of Ti_(2)Ni precipitates in TiNi shape memory alloy fabricated by selective laser melting

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

journal of Materials Science & Technology 2022年第6期101卷 205-216页

作者： H.Z.Lu L.H.Liu C.Yang X.Luo C.H.Song Z.wang j.wang Y.D.Su Y.F.Ding L.C.Zhang Y.Y.Li National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Musculoskeletal Oncology Department Sun Yat-Sen University Cancer CenterGuangzhouGuangdong ProvinceChina Shenyang Aircraft Design and Research Institute Shenyang 110035China Guangdong Huayi Plumbing Fittings Industry Co. Ltd.Kaiping 529321China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA 6027Australia

The excellent shape memory and mechanical properties of Ti Ni shape memory alloys(SMAs) fabricated using selective laser melting(SLM) are highly desirable for a wide range of critical applications. In this study, we examined the simultaneous enhancement of mechanical and shape memory properties using heat-treatment homogenization of Ti_(2)Ni precipitates in a Ti_(50.6)Ni_(49.4)SMA fabricated using SLM. Specifically, because of the complete solution treatment, nanoscale spherical Ti_(2)Ni precipitates were homogeneously dispersed throughout the grain interior. Interestingly, the resultant SMA exhibited an ultrahigh tensile strength of 880 ± 13 MPa, a large elongation of 22.4 ± 0.4%, and an excellent shape memory effect, with a recovery rate of > 98% and ultrahigh recoverable strain of 5.32% after ten loading–unloading cycles. These simultaneously enhanced properties are considerably superior than those of most previously reported Ti Ni SMAs fabricated using additive manufacturing. Fundamentally, the enhancement in tensile strength is ascribed to precipitation strengthening and work hardening, and the large plasticity is mainly attributed to the homogeneous nanoscale globular Ti_(2)Ni precipitates, which effectively impeded the rapid propagation of microcracks. Furthermore, the enhanced shape memory properties are derived from the suppression of dislocation movement and formation of retained stabilized martensite by the presence of high-density dislocations, nanoscale Ti_(2)Ni precipitates, and abundant interfaces. The obtained results provide insight into the enhancement of the two types of properties in Ti Ni SMAs and will accelerate the wider application of SMAs.

关键词： Shape memory alloy Selective laser melting Heat treatment Mechanical properties Shape memory properties

激光修整圆柱形CBN砂轮中偏焦量对能量分布的影响

在线全文

学校读者我要写书评

暂无评论

中国机械工程 2006年第7期17卷 702-705页

作者：王续跃 Y.Wu 徐文骥王连吉 j.wang 大连理工大学精密与特种加工教育部重点实验室大连116023 秋田县立大学新南威尔士大学

激光束偏焦量是修整圆柱形砂轮的重要参数,它影响光斑形状及其能量密度,因而影响激光修整砂轮的质量。介绍了用数控Nd:YAG激光系统修整圆柱形CBN砂轮过程中,偏焦量对光斑作用能量分布的影响与其修整作用的基本原理,建立了激光偏焦量作... 详细信息

激光束偏焦量是修整圆柱形砂轮的重要参数,它影响光斑形状及其能量密度,因而影响激光修整砂轮的质量。介绍了用数控Nd:YAG激光系统修整圆柱形CBN砂轮过程中,偏焦量对光斑作用能量分布的影响与其修整作用的基本原理,建立了激光偏焦量作用于圆柱形砂轮上任意一点的光斑面积数学模型;给出了调整激光偏焦量修整圆柱形砂轮的关系与参数范围;采用计算与试验结合的方法,得到激光偏焦量、输入能量密度及激光修整参数的对应关系。研究结果为进一步提高激光修整圆柱形陶瓷结合剂CBN砂轮的质量提供了理论与试验依据。

关键词：激光技术砂轮修整偏焦量数学模型

Preparation and growth mechanism of nickel nanowires under applied magnetic field

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2010年第2期2卷 134-138页

作者： j.wang L.Y.Zhang P.Liu T.M.Lan j.Zhang L.M.Wei Eric Siu-Wai Kong C.H.jiang Y.F.Zhang National Key Laboratory of Nano/Micro Fabrication Technology Key Laboratory for Thin Film and Microfabrication of the Ministry of Education Institute of Micro and Nano Science and Technology Shanghai Jiao Tong University School of Materials Science and Engineering Shanghai Jiao Tong University Zhongyuan University of Technology

Nickel nanowires with large aspect ratio of up to 300 have been prepared by a hydrazine hydrate reduction method under applied magnetic field. The diameter of nickel nanowires is about 200 nm and length up to 60 μm. The role of magnetic field on the growth of magnetic nanowires is discussed and a magnetic nanowire growth mechanism has been proposed. Nickel ions are firstly reduced to nickel atoms by hydrazine hydrates in a strong alkaline solution and grow into tiny spherical nanoparticles. Then, these magnetic particles will align under a magnetic force and form linear chains. Furthermore, the as-formed chains can enhance the local magnetic field and attract other magnetic particles nearby, resulting finally as linear nanowires. The formation and the size of nanowires depend strongly on the magnitude of applied magnetic field.

关键词： Nanowire growth mechanism Nickel nanowires Magnetic-field assisted synthesis

国外城市土地利用与交通一体规划的方法与实践

在线全文

学校读者我要写书评

暂无评论

国际城市规划 2009年第S1期24卷 205-209页

作者：王缉宪香港大学地理系

本文从方法论和规划实践两个方面介绍欧美日澳等地学者对城市土地利用与交通一体规划的最新研究进展。在方法论方面集中介绍了北美学者对过去40年世界各国特别是欧美在城市用地交通一体化模型研究上的进展、问题、反思和展望。在过去的1... 详细信息

本文从方法论和规划实践两个方面介绍欧美日澳等地学者对城市土地利用与交通一体规划的最新研究进展。在方法论方面集中介绍了北美学者对过去40年世界各国特别是欧美在城市用地交通一体化模型研究上的进展、问题、反思和展望。在过去的10年里,包含可持续发展思想的对环境质量和社会公平的诉求使得这种一体化模型变得重要起来;而研究者在把环境、土地利用和交通放在一起模拟有关政策的效果时发现,由于种种原因,对城市交通的了解程度和模拟技术远远超过对土地使用和土地市场的模拟能力。在规划实践方面,本文着重介绍了美国学者塞维诺关于世界12个不同城市的报告和分析,这些城市在过去30年中比较成功地规划和协调了土地利用、城市格局和公共交通的发展。

关键词：城市土地利用城市交通公交导向式

Toward pluripotency by reprogramming:mechanisms and application

在线全文

学校读者我要写书评

暂无评论

Protein & Cell 2013年第11期4卷 820-832页

作者： Tao wang stephen TWarren Peng jin Department of Human Genetics Emory UniversityAtlantaGA 30322USA Genetics and Molecular Biology Graduate Program Emory UniversityAtlantaGA 30322USA

The somatic epigenome can be reprogrammed to a pluri-potent state by a combination of transcription *** cell fate involves transcription factors coopera-tion,epigenetic reconfi guration,such as DNA methylation and histone modification,posttranscriptional regulation by microRNAs,and so ***,such reprogram-ming is *** suggests that during the early stage of reprogramming,the process is stochastic,but by the late stage,it is *** addition to con-ventional reprogramming methods,dozens of small mol-ecules have been identifi ed that can functionally replace reprogramming factors and signifi cantly improve induced pluripotent stem cell(iPSC)***,iPS cells have been created recently using chemical com-pounds *** are thought to display subtle genetic and epigenetic variability;this variability is not random,but occurs at hotspots across the *** we dis-cuss the progress and current perspectives in the fi *** into the reprogramming process today will pave the way for great advances in regenerative medicine in the future.

关键词： epigenetic reprogramming induced pluripo-tent stem cells embryonic stem cells disease modeling

A Real-Space Phase Field Model for Domain Evolution of Ferromagnetic Materials

在线全文

学校读者我要写书评

暂无评论

A Real-Space Phase Field Model for Domain Evolution of Ferro...

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

The 16th Annual Conference of Hong Kong Society of Theoretical and Applied Mechanics 2012、The 1st Mainland-Hong Kong Youth Forum on Mechanics 2012、The 8th Shanghai-Hong Kong Forum on Mechanics and Its Application 2012

作者： j.wang j.W.Zhang Department of Engineering Mechanics Zhejiang University

Ferromagnetic materials have been an important type of smart materials and are widely utilized in different magnetic devices due to their distinguished magneto-elastic coupling properties. The magneto-elastic coupling properties of ferromagnetic materials are dependent on the magnetic domain *** stable domain structures are determined by the competition between different energies of the materials,including the magnetocrystalline anisotropy energy,exchange energy (domain wall energy),elastic energy and magnetic *** study the domain structures of ferromagnetic materials,different phase field models have been developed in the literature[1].Most phase-field models in the literature employ the periodic boundary conditions,and thus the results are only valid when the simulation system size is much smaller than the actual sample size. In the present work,a real-space phase field model based on the time-dependent Ginzburg-Landau (TDGL) equation is developed to predict the domain evolution of ferromagnetic *** phase field model stems from a thermodynamic theory of ferromagnetic materials which employs the strain and magnetization as independent *** phase field equations are shown to reduce to the common micromagnetic model where the magnetostriction is absent and the magnitude of magnetization is *** strain and magnetization in the equilibrium state are obtained simultaneously by solving the phase field equations via a nonlinear finite element *** finite-element based phase field model is applicable for the domain evolution of ferromagnetic materials with arbitrary geometries and boundary *** evolution of magnetization domains in ferromagnetic thin film subjected to external stresses and magnetic fields are simulated and the magnetoelastic coupling behaviour is *** field simulations show that the magnetization vectors form a single magnetic vortex in ferromagnetic disks and *** configuration

关键词： Model A Real-Space Phase Field Model for Domain Evolution of Ferromagnetic Materials

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue Tong Shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li Yan wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Oxygen vacancy Hydrocarbon production Reaction mechanism

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HCHO driven by photoelectrocatalysis

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

journal of Energy Chemistry 2025年第1期100卷 39-49页

作者： Hongqiang Yang jianfeng Zheng Guoyu wang Yifei Gao Yatao Yang jia Li Xiaojin Han Yan Cui Zhanggen Huang National Key Laboratory of High Efficiency and Low Carbon Utilization of Coal Institute of Coal Chemistry Chinese Academy of Science University of Chinese Academy of Science Shenyang University of Chemical Technology

Photoelectrocatalytic coupling CO2and volatile organic compounds （VOCs） is a promising green strategy for the synergistic conversion of the two carbon-containing resources to *** catalytic efficiency is always at the mercy of chemical inertness of CO2and the competitive hydrogen evolution of ***,a modified g-C3N4/ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely *** Faraday efficiency of ethanol reached 68.67%with a corresponding formation rate of 227.3μmol *** revealed by in-situ characterizations and density functional theory calculations,CO2and HCHO were absorbed at Zn site and N site,***,*CO generated from CO2and HCHO was converted to*CH3O and*CHO on the dual-active-site *** detailed reaction mechanism experiments indicated that C–C coupling only occurred between*CO and*CH3O in electrocatalysis *** from the“*CO+*CH3O”path,another“*CO+*CHO”coupling path was also detected in photoelectrocatalytic *** selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2and HCHO simultaneously driven by light and electricity.

关键词： Photoelectrocatalysis Z-scheme C–C coupling Ethanol

Inflammasome links traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第6期20卷 1644-1664页

作者： Gabriela Seplovich Yazan Bouchi juan Pablo de Rivero Vaccari jennifer C.Munoz Pareja Andrew Reisner Laura Blackwell Yehia Mechref Kevin K.wang j.Adrian Tyndall Binu Tharakan Firas Kobeissy Department of Surgery Morehouse School of MedicineAtlantaGAUSA Department of Neurobiology Center for NeurotraumaMultiomics&Biomarkers(CNMB)Neuroscience InstituteMorehouse School of MedicineAtlantaGAUSA Department of Neurological Surgery and the Miami Project to Cure Paralysis University of Miami Miller School of MedicineMiamiFLUSA Division of Pediatric Critical Care Department of PediatricsUniversity of Miami Miller School of MedicineMiamiFLUSA Department of Pediatrics Emory UniversityAtlantaGAUSA Department of Neurosurgery Children’s Healthcare of AtlantaAtlantaGAUSA Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTXUSA Morehouse School of Medicine AtlantaGAUSA

Traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease are three distinct neurological disorders that share common pathophysiological mechanisms involving neuroinflammation. One sequela of neuroinflammation includes the pathologic hyperphosphorylation of tau protein, an endogenous microtubule-associated protein that protects the integrity of neuronal cytoskeletons. Tau hyperphosphorylation results in protein misfolding and subsequent accumulation of tau tangles forming neurotoxic aggregates. These misfolded proteins are characteristic of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease and can lead to downstream neuroinflammatory processes, including assembly and activation of the inflammasome complex. Inflammasomes refer to a family of multimeric protein units that, upon activation, release a cascade of signaling molecules resulting in caspase-induced cell death and inflammation mediated by the release of interleukin-1β cytokine. One specific inflammasome, the NOD-like receptor protein 3, has been proposed to be a key regulator of tau phosphorylation where it has been shown that prolonged NOD-like receptor protein 3 activation acts as a causal factor in pathological tau accumulation and spreading. This review begins by describing the epidemiology and pathophysiology of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease. Next, we highlight neuroinflammation as an overriding theme and discuss the role of the NOD-like receptor protein 3 inflammasome in the formation of tau deposits and how such tauopathic entities spread throughout the brain. We then propose a novel framework linking traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease as inflammasomedependent pathologies that exist along a temporal continuum. Finally, we discuss potential therapeutic targets that may intercept this pathway and ultimately minimize long-term neurological decline.

关键词： Alzheimer's disease caspase-1 chronic traumatic encephalopathy inflammasomes neurodegeneration neuroinflammation NLRP1 NLRP3 pyroptosis tauopathy traumatic brain injury