期刊文献+
共找到551,957篇文章
< 1 2 250 >
每页显示 20 50 100
基于Mechanism/Pro的汽车悬架系统运动仿真
1
作者 武志斐 王铁 张瑞亮 《计算机仿真》 CSCD 2008年第8期263-267,共5页
为了解决多体动力学分析仿真过程中困扰仿真人员的模型建立和修改问题,以汽车独立悬架为研究对象,提出机械系统仿真一种比较理想的方法。首先应用多体动力学求解理论,从悬架物理模型中提取多体动力学求解模型,针对ADAMS/View建模能力较... 为了解决多体动力学分析仿真过程中困扰仿真人员的模型建立和修改问题,以汽车独立悬架为研究对象,提出机械系统仿真一种比较理想的方法。首先应用多体动力学求解理论,从悬架物理模型中提取多体动力学求解模型,针对ADAMS/View建模能力较弱,通过三维建模软件Pro/E建模,采用Mechanism/Pro模块定义刚体、添加约束和驱动、调用ADAMS/Sol-ver求解。可以很方便地建立复杂机械系统模型,并根据仿真结果及时对模型进行修改,实现机械系统多体动力学仿真的前处理、求解以及后处理均集成在Pro/E环境中。 展开更多
关键词 机械系统仿真 汽车悬架 运动仿真 系统集成
在线阅读 下载PDF
Antibacterial Activity and Mechanism of Thyme Essential Oil Nanoemulsion Prepared with Potato Protein Modified by Transglutaminase (TGase) against Staphylococcus aureus and Escherichia coli: A Metabolomic Study
2
作者 YUAN Ruoyun CHANG Tong +6 位作者 WANG Yilin XU Xin LÜFengzhang WANG Miao MA Chengye LI Hongjun WANG Chenjie 《食品科学》 北大核心 2026年第1期17-28,共12页
In this study,thyme essential oil(TEO)nanoemulsion(tPTNs)was constructed with transglutaminase(TGase)-modified potato protein,and its antibacterial activity and mechanism of action were evaluated and explored.Results ... In this study,thyme essential oil(TEO)nanoemulsion(tPTNs)was constructed with transglutaminase(TGase)-modified potato protein,and its antibacterial activity and mechanism of action were evaluated and explored.Results indicated that tPTNs exhibited great antibacterial activity against both Staphylococcus aureus and Escherichia coli,with minimal inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of 2.5 and 5.0 mg/mL,respectively.Also,the antibacterial effects of tPTNs were concentration-dependent.We observed a significant decrease in the absolute value of the zeta potential,and significant increases in particle size,cell membrane hydrophobicity,conductivity,the release of metal ions,and the leakage of nucleic acid as the concentration of tPTNs increased from 0 mg/mL to MBC.Furthermore,sodium dodecyl sulphate-polyacrylamide gel electrophoresis(SDS-PAGE)demonstrated that protein synthesis was inhibited or even disrupted.Analysis by liquid chromatography-mass spectrometry(LC-MS)indicated that treatment with tPTNs caused significant changes in bacterial metabolites,1117 and 692 differential metabolites being found for S.aureus and E.coli,respectively.The differential metabolites were involved in nucleotide metabolism,amino acid metabolism,tricarboxylic acid cycle and other metabolic pathways.These findings provide valuable insights for the application of thyme essential oil as an efficient antibacterial agent and for the understanding of its mechanism of action. 展开更多
关键词 potato protein thyme essential oil NANOEMULSIONS antibacterial mechanism metabolomics
在线阅读 下载PDF
Progress in MOF-based catalyst design and reaction mechanisms for CO_(2)hydrogenation to methanol
3
作者 YU Zhifu JIANG Lei WU Mingbo 《燃料化学学报(中英文)》 北大核心 2026年第1期146-162,共17页
Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon... Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies. 展开更多
关键词 CO_(2)hydrogenation metal-organic frameworks(MOFs) catalyst design reaction mechanism METHANOL
在线阅读 下载PDF
Cross-scale investigation of overcharge-induced thermal runaway propagation mechanism in sodium-ion batteries under multi-module configuration
4
作者 Qinghua Gui Jinzhong Li +4 位作者 Bowen Jin Peng Liu Kun Yu Jiarui Zhang Lei Mao 《Journal of Energy Chemistry》 2026年第1期13-28,I0002,共17页
In electrochemical energy storage systems,the sodium-ion battery is typically integrated in the form of a“cell-module-cluster”,but its cross-scale thermal runaway triggering risk and the propagation mechanism remain... In electrochemical energy storage systems,the sodium-ion battery is typically integrated in the form of a“cell-module-cluster”,but its cross-scale thermal runaway triggering risk and the propagation mechanism remain unclear.This study reveals the cross-scale thermal runaway triggering and propagation behavior of sodium-ion batteries of“cell-module-cluster”under overcharge conditions,and investigates the effects of key factors,including module spacing,triggering cell location,and heat dissipation condition,on the thermal runaway propagation behavior.Results demonstrate that the thermal runaway propagation in a module containing the overcharged cell follows a sequential triggering mode,while thermal runaway in the downstream module exhibits a simultaneous triggering mode with greater severity.Furthermore,increasing the module spacing or enhancing the heat dissipation capacity can effectively reduce the heat accumulation and prevent the trigger of thermal runaway.On the above basis,the multi-dimensional evaluation strategy is proposed to quantitatively assess the hazard of sodium-ion battery cluster thermal runaway.The findings serve as a foundation for the safe design of sodium-ion batteries in energy storage systems. 展开更多
关键词 Cross-scale Sodium-ion battery OVERCHARGE Thermal runaway propagation mechanism
在线阅读 下载PDF
Controllable phase-reconstruction strategy for LiFePO_(4)homogeneous regeneration:Reaction mechanism,characterization and prospect
5
作者 Zihao Zeng Yi Chen +4 位作者 Chao Zhu Hai Lei Wei Sun Yue Yang Peng Ge 《Journal of Energy Chemistry》 2026年第1期553-571,I0013,共20页
The growing volume of end-of-life lithium-ion batteries(LIBs)represents both an urgent environmental challenge and a critical resource opportunity,especially for cathode materials.Among commercial cathodes,LiFePO4(LFP... The growing volume of end-of-life lithium-ion batteries(LIBs)represents both an urgent environmental challenge and a critical resource opportunity,especially for cathode materials.Among commercial cathodes,LiFePO4(LFP)dominates the market due to its favorable properties;thus,a substantial amount of LFP cathode materials is expected to retire in the near future.The conventional hydrometallurgical method suffers from high costs and serious pollution.Direct regeneration technologies,especially solid-state sintering,provide a more efficient and environmentally benign alternative by repairing cathode structures through high-temperature solid-phase reactions without extra chemical reagents.Traditional solid-state sintering faces challenges in processing spent LFP from diverse sources,struggling to achieve the homogenization of physical–chemical properties and electrochemical performance.To address the limitations above,phase homogenization with a lattice reconstruction strategy has been investigated,which can enable effective lattice reconstruction and microstructural homogenization,demonstrating robust adaptability to spent samples from variable sources.This review systematically summarizes the mechanisms,detailed steps,characterization techniques,and advances in pre-oxidation optimization(including ion-doping and coated carbon layer modification),as well as future research directions for sustainable LFP recycling.Given this,this review is expected to offer theoretical guidance for achieving homogeneous regeneration of LFP cathode. 展开更多
关键词 Spent LiFePO_(4) REGENERATION Phase-reconstruction Reaction mechanism CHARACTERIZATION
在线阅读 下载PDF
Dynamic compressive mechanical properties and fracture mechanism of conglomerate
6
作者 WANG Mi CHEN Xiao-bin +2 位作者 TANG Lu-bo WANG Ye-shun LIANG Wei-qun 《Journal of Central South University》 2026年第1期299-316,共18页
Conglomerate rock's complex and heterogeneous microstructure significantly affects its mechanical properties,especially under dynamic loading.However,research on their dynamic behavior and fracture mechanisms is l... Conglomerate rock's complex and heterogeneous microstructure significantly affects its mechanical properties,especially under dynamic loading.However,research on their dynamic behavior and fracture mechanisms is limited.Through uniaxial compression tests and split Hopkinson pressure bar(SHPB)impact tests,the dynamic compressive mechanical properties and fracture mechanisms of conglomerate rock were studied.Nanoindentation and high-resolution X-ray computed tomography were employed to analyze the micro-mechanical behavior and internal structure of the conglomerate rock.Results indicate significant differences in mechanical properties between different gravel particles and cementing materials,with initial fractures primarily distributed at the gravel-cement interfaces.The dynamic mechanical properties of conglomerate rocks exhibit a clear strain rate dependency.Based on the stress−strain curves and failure characteristics,the dynamic compressive mechanical behavior can be categorized into two types using a critical strain rate.The dynamic compressive strength,peak strain,and toughness of conglomerate rock increased with the strain rate,with the strength at 54 s−1 being 2.6 times that at 6 s−1.The dynamic compressive fracture mechanism of conglomerate rock is related to the strain rate and microstructure;at low strain rates,gravel distribution is the key factor,whereas at high strain rates,gravel content becomes critical. 展开更多
关键词 CONGLOMERATE compressive response realistic micro-heterogeneity fracture mechanism strain rate dependency
在线阅读 下载PDF
Genesis Mechanism of Heat Source in Mianhuakeng Uranium Deposit,South China:Insights from Radiogenic Heat Production of Granite Bodies
7
作者 WANG Siqi ZHANG Baojian +2 位作者 LÜGuosen LIU Feng ZHU Xi 《Acta Geologica Sinica(English Edition)》 2026年第1期286-296,共11页
The Mianhuakeng uranium deposit,characterized by uranium-rich granite,serves as a key site for research into crustal radioactive heating.Based on 45 rock samples,this study reviews that the host granite in the Mianhua... The Mianhuakeng uranium deposit,characterized by uranium-rich granite,serves as a key site for research into crustal radioactive heating.Based on 45 rock samples,this study reviews that the host granite in the Mianhuakeng uranium deposit has a high radioactive heat production rate(avg.5.50μW/m³)and a low Th/U ratio(avg.2.62).Uranium-rich granite and its alteration zone within the upper crust(0-5 km depth)contribute about 45%of the total radioactive heat production,wich is crucial for controlling geothermal resource distribution.For uranium-thermal at tectonic plate margins,a symbiotic geological model was proposed:Firstly,subduction of the Pacific Plate caused upwelling of the asthenosphere,generating a high heat-flow background.Secondly,heat transfer is enhanced by major faults such as the Youdong and Mianhuakeng faults.Subsequently,uranium was mobilized,transported,and enriched within the granite through deep siliceous hydrothermal activity and associated alteration.Ultimately,the uranium enrichment in granite leads to increased radioactive heat production,resulting in local thermal anomalies.This model provides a theoretical support for exploring and developing uranium-thermal symbiotic resources in South China. 展开更多
关键词 uranium-rich granite radiogenic heat production heat source genesis mechanism Mianhuakeng uranium deposit
在线阅读 下载PDF
Observation on the Efficacy and Mechanism of Blood-Letting and Cupping Therapy in Improving Upper Limb Lymphedema after Breast Cancer Surgery
8
作者 Dongli Zhang Jia Liu Qian Zheng 《Proceedings of Anticancer Research》 2026年第1期115-121,共7页
Objective:To evaluate the clinical efficacy of blood-letting cupping combined with manual lymphatic drainage in treating breast cancer-related lymphedema(BCRL)and explore its mechanism of action from both traditional ... Objective:To evaluate the clinical efficacy of blood-letting cupping combined with manual lymphatic drainage in treating breast cancer-related lymphedema(BCRL)and explore its mechanism of action from both traditional Chinese medicine and modern medical perspectives,providing a scientific basis and novel therapeutic approaches for clinical management of BCRL.Methods:Patients with BCRL admitted to the outpatient and inpatient departments of Hebei University Affiliated Hospital were enrolled.A prospective randomized controlled trial design was adopted,with eligible patients randomly assigned to a treatment group and a control group.The control group received manual lymphatic drainage alone,while the treatment group received manual lymphtic drainage combined with blood-letting cupping therapy.Posttreatment comparisons evaluated upper limb circumference reduction,edema severity grading,and upper limb functional scores.Vital signs and adverse reactions during treatment were recorded for both groups.Statistical software analyzed the data.Results:The treatment group demonstrated significantly greater reduction in upper limb circumference,improvement in edema severity,and higher upper limb function scores compared to the control group(P<0.05).Vital signs remained stable throughout treatment in both groups.No severe adverse reactions occurred in the treatment group;only isolated cases of mild skin itching were reported,which resolved after symptomatic management.Conclusion:The combination of bloodletting cupping and manual lymphatic drainage demonstrates reliable efficacy in treating BCRL,effectively alleviating edema symptoms and improving upper limb function with high safety.Its mechanism may relate to traditional Chinese medicine principles of“unblocking meridians,promoting blood circulation,and resolving stasis”and modern medical concepts of“enhancing local blood circulation,facilitating lymphatic drainage,and reducing inflammatory responses”. 展开更多
关键词 Blood-letting cupping Postoperative breast cancer Upper limb lymphedema Efficacy observation mechanism of action
暂未订购
Long-term Mechanism and Implementation Path of Increasing Income of Rural Low-income Population in Zhejiang Province from the Perspective of Common Prosperity
9
作者 Peiyi YE 《Asian Agricultural Research》 2026年第2期23-26,共4页
Taking the rural low-income population of Zhejiang Province as its subject, this paper examines how to build a sustainable income-growth mechanism and identify feasible implementation paths within the context of the c... Taking the rural low-income population of Zhejiang Province as its subject, this paper examines how to build a sustainable income-growth mechanism and identify feasible implementation paths within the context of the common prosperity strategy. The research identifies key obstacles to income expansion, including an undiversified industrial structure, insufficient human capital, and a lack of robust social protection. These call for systemic solutions featuring institutional innovation, resource consolidation, and capability enhancement. Building on Zhejiang's experience as a common prosperity demonstration zone, the article constructs an integrated framework centered on four pillars: industrial empowerment, education upgrading, social security reinforcement, and digital coordination. It further offers concrete policy proposals involving the cultivation of localized industries, vocational skill training, enhanced safety nets, and the adoption of digital tools. The study thus offers both theoretical insights and practical paradigms for tackling the challenge of raising incomes in low-income rural areas. 展开更多
关键词 Common prosperity Rural low-income population Long-term mechanism of increasing income Implementation path Zhejiang province
在线阅读 下载PDF
Mechanical properties and mechanisms of soft clay treated by all-industrial by-product binder in alkali-sulfate activating framework
10
作者 Dongxing Wang Sichen Li +3 位作者 Yalei Wu Jun Hu Shu Lin Yongzhi Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期745-760,共16页
Soft clay treatment with all industrial by-product(IBP)binder has great economic and environmental benefits,yet its geomechanics and mechanisms still need to be well probed.With the activation by calcium carbide resid... Soft clay treatment with all industrial by-product(IBP)binder has great economic and environmental benefits,yet its geomechanics and mechanisms still need to be well probed.With the activation by calcium carbide residue(CCR)and phosphogypsum(PG),the strength,structure,and mechanisms of soft clay treated by aluminosilicate-rich IBP(AS-IBP,such as ground granulated blast furnace slag(GGBS),fly ash(FA),coal gangue(CG),Bayer red mud(BR),and sintered red mud(SR))are comparatively investigated.The strength characteristics of solidified clay exhibit significant differences as AS-IBP changes.When GGBS is adopted,the strength is sensitive to the change in PG content,while the impact of CCR is insignificant.After 90 d,the strength of the optimal sample(G23)reaches 1.40 MPa,35.9%higher than cement solidified clay(CSC),while that achieved by other AS-IBPs is less than 0.3 MPa.In the compression test,the structure's evolutionary trend of G23 has a sudden change as the strength increases from 1.81 MPa to 2.29 MPa,suggesting the transformation in material properties.Besides,the structure of G23 is stronger than CSC,which contributes more to the compressive performance.The total amount of main products(C-S-H and ettringite)of all-IBP solidified clay determines the strength,and ettringite is only significant when calcium-rich AS-IBP is adopted.The total amount of minor products(C-A-H and C-A-S-H)is similar for different samples,equivalent to 28.9%-46.3%of the main products.The relationship between the strength and the product amount can be presented using an exponential function. 展开更多
关键词 Soft clay Industrial by-products(IBPs) Unconfined compressive strength(UCS) Structural behavior Microscopic mechanism
在线阅读 下载PDF
Double Ionization to CO_(2) Produces Molecular Oxygen:A Roaming Mechanism
11
作者 Qibo Ma Xintai Hao +5 位作者 Jiaqi Zhou Xiaorui Xue Qingrui Zeng Peng Li Lei Wang Xueguang Ren 《Chinese Physics Letters》 2026年第1期17-25,共9页
Abiotic oxygen formation predates photosynthesis,sustaining early chemical evolution,yet its elementary mechanisms remain contested.Here,we show the production pathways for molecular oxygen from doubly ionized carbon ... Abiotic oxygen formation predates photosynthesis,sustaining early chemical evolution,yet its elementary mechanisms remain contested.Here,we show the production pathways for molecular oxygen from doubly ionized carbon dioxide upon electron-impact.Through fragment ions and electron coincidence momentum imaging,we unambiguously determine the ionization mechanism by measuring the projectile energy loss in association with the C^(+) +O_(2)^(+) channel.Further potential energy and trajectory calculations enable us to elucidate the dynamical details of this fragmentation process,in which a bond rearrangement pathway is found to proceed via the structural deformation to a triangular intermediate.Moreover,we demonstrate a further roaming pathway for the formation of O_(2)^(+) from CO_(2)^(+) 2,in which a frustrated C-O bond cleavage leaves the O atom without sufficient energy to escape.The O atom then wanders around varied configuration spaces of the flat potential energy regions and forms a C-O-O_(2)^(+) intermediate prior to the final products C^(+) +O_(2)^(+).Considering the large quantities of free electrons in interstellar space,the processes revealed here are expected to be significant and should be incorporated into atmospheric evolution models. 展开更多
关键词 carbon dioxide projectile energy loss abiotic oxygen double ionization fragment ions potential energy trajectory calculations ionization mechanism electron coincidence momentum imagingwe
原文传递
Integrating bulk and single-cell transcriptome profiling to uncover diagnostic biomarkers and regulatory mechanisms of oxidative stress in spinal cord injury
12
作者 Jianfeng Li Kuileung Tong +9 位作者 Jiaxiang Zhou Shiming Li Zhongyuan He Fuan Wang Hongkun Chen Haizhen Li Gang Cheng Junhong Li Zhiyu Zhou Manman Gao 《Neural Regeneration Research》 2026年第6期2643-2657,共15页
Oxidative stress significantly contributes to secondary damage after spinal cord injury.Despite its importance,research on oxidative stress in spinal cord injury remains limited.Investigating the expression and regula... Oxidative stress significantly contributes to secondary damage after spinal cord injury.Despite its importance,research on oxidative stress in spinal cord injury remains limited.Investigating the expression and regulation of oxidative stress-related genes could enhance the diagnosis and treatment of spinal cord injury.In this study,we analyzed the sequencing data of human blood samples and injured mouse spinal cord tissue that were sourced from GEO databases and identified diagnostic biomarkers associated with the severity of spinal cord injury.We also explored the expression patterns of oxidative stress-related genes,potential regulatory mechanisms,and therapeutic drugs.To validate our findings,we performed immunofluorescence and quantitative polymerase chain reaction to assess gene expression in the injured spinal cord.Our results revealed biomarkers associated with oxidative stress and immune responses across different levels of spinal cord injury in humans.We identified differentially expressed oxidative stress-related genes and key hub genes in injured mouse spinal cord tissue and revealed their temporal expression patterns at both the tissue and single-cell levels.We also clarified the signaling pathways associated with oxidative stress and identified ligand-receptor pairs among various cell types at different time points after injury.Furthermore,we discovered microRNAs,long non-coding RNAs,and transcription factors that regulate these hub genes and revealed their roles in modulating gene expression at various stages after spinal cord injury.We also identified drugs targeting these hub genes.The findings from this study not only aid in identifying diagnostic biomarkers that reflect the severity of spinal cord injury,but also provide insights into the expression dynamics of oxidative stress-related genes.In addition,the study reveals potential regulatory mechanisms and identifies potential drugs to treat patients with spinal cord injury. 展开更多
关键词 bioinformatics analysis diagnostic biomarker drug intervention expression characteristics immune change oxidative stress regulation mechanism severity of the illness spinal cord injury spinal cord repair
暂未订购
Material removal mechanism of SiC_(f)/SiC composites during ultrasonic-assisted scratching with vertical vibration 被引量:1
13
作者 Zhigang DONG Guoqing YUAN +3 位作者 Yichuan RAN Haiqi SUN Jiansong SUN Yan BAO 《Chinese Journal of Aeronautics》 2026年第1期584-600,共17页
Ultrasonic-Assisted Grinding(UAG)is a novel manufacturing technology that shows promising promise for use in processing Ceramic Matrix Composites(CMCs).Nevertheless,analyzing the material removal process of CMCs with ... Ultrasonic-Assisted Grinding(UAG)is a novel manufacturing technology that shows promising promise for use in processing Ceramic Matrix Composites(CMCs).Nevertheless,analyzing the material removal process of CMCs with multidirectional structure during UAG is challenging,impeding the progress and improvement of the UAG process.This work examined the impact of ultrasonic vibration on the dynamic mechanical characteristics during processing.Additionally,we experimentally elucidated the material removal mechanism of CMCs during the scratching process under the influence of vertical vibration.The results indicate that the introduction of ultrasonic vibration causes a strain rate effect,resulting in a modification of the material removal mechanism,subsequently impacting the processing quality.Ultrasonic vibration increases the dynamic strength and brittleness of the fibers in CMCs,leading to more cracks at fracture,which changes from the original bending fracture to shear fracture.In addition,ultrasonic vibration can effectively inhibit the impact of scratching depth and anisotropy on the removal mechanism of CMCs,resulting in a more uniform surface of CMCs after processing. 展开更多
关键词 Ceramic-matrix composites Ultrasonic assisted scratching(UAS) Strain rate effect Dynamic mechanical property Material removal mechanism
原文传递
Study on the damage mechanism of high chromia refractory in the slag ta
14
作者 PENG Baozi LIU Zhen +4 位作者 BAI Jin LI Huaizhu SUN Kaidi AN Haiquan LI Jun 《燃料化学学报(中英文)》 北大核心 2026年第3期170-179,共10页
The service life of refractory brick in the slag tapping hole of gasifiers is a significant concern for long-term and stable operation.This study examined the damage mechanism of high chromia refractory of four commer... The service life of refractory brick in the slag tapping hole of gasifiers is a significant concern for long-term and stable operation.This study examined the damage mechanism of high chromia refractory of four commercial coal-water slurry gasifiers with their corresponding gasification coal samples and the corroded refractory bricks in the slag tapping hole of the gasifier.The slag characteristic,including crystallization and viscosity-temperature of four gasification coal samples were analyzed.The results revealed that the low viscosity slag could lead to more severe damage to refractory bricks.Given the risk of slag crystallization,it is recommended to establish a safe slag tapping temperature range should be set as tICT(initial crystallization temperature)−t_(2.5) when tICT is higher than t_(25).Upon examining interior morphology of these corroded refractory bricks,some cracks were observed within them.The chemical composition of molten slag was analyzed using SEM-EDS.However,XRD results found no spinel containing zirconium in these cracks.This suggests that the emergence of these cracks are mainly attributed to the molten slag penetration and the subsequent reaction with the refractory material.The difference in thermal expansion between the newly formed substances and refractory material is critical in forming these cracks.Furthermore,SEM-EDS analysis was also conducted on the slag-aggregate and the slag-matrix interface.The results reveal that the reduction in Cr_(2)O_(3) content is the earliest characteristic of damage in high chromia refractories.A proposed damage mechanism of refractory brick suggests that the matrix and aggregate of high chromia refractory are initially compromised because of the reduced Cr_(2)O_(3) content.Subsequently,the molten slag penetrates the interior of the refractory brick,forming new substances,leading to damage caused by the difference in thermal expansion between the new substances and the refractory brick.Understanding and preventing the reduction of Cr_(2)O_(3) content is vital to prolonging the service life of refractory brick in the slag tapping hole of the gasifier based on this damage mechanism. 展开更多
关键词 GASIFICATION high chromia refractory SLAG damage mechanism corrosion
在线阅读 下载PDF
Effect of Argon Atmosphere Heat Treatment on Mechanical Properties and Microstructural Evolution of Shicolon-Ⅱ SiC Fibers
15
作者 YUAN Wang HU Jianbao +3 位作者 ZHOU Liang KAN Yanmei ZHANG Xiangyu DONG Shaoming 《无机材料学报》 北大核心 2026年第1期119-128,共10页
Silicon carbide fibers are considered ideal reinforcing materials for ceramic matrix composites due to their excellent mechanical properties and high-temperature performance.Different types of fibers necessitate indiv... Silicon carbide fibers are considered ideal reinforcing materials for ceramic matrix composites due to their excellent mechanical properties and high-temperature performance.Different types of fibers necessitate individual investigation due to variations in their composition and fabrication processes.This study presents a comprehensive investigation into evolution of the mechanical properties,surface microstructure,and composition of Shicolon-Ⅱ fibers subjected to argon heat treatment at temperatures ranging from 1300℃to 1700℃.The Shicolon-Ⅱ fibers are composed of small-sized β-SiC grains,SiC_(x)O_(y) amorphous phase,and a minor amount of graphite microcrystals.Following treatment in an argon atmosphere at 1300℃,the fibers maintain a monofilament tensile strength of 3.620 GPa,corresponding to a retention of 98.32%.This strength diminishes to 2.875 GPa,equating to a retention of 78.08%,after treatment at 1500℃.The reduction in mechanical properties of the fibers can be ascribed to the decomposition of the amorphous phase and the growth of β-SiC grains.Furthermore,creep resistance is an essential factor influencing the long-term performance of composite materials.After treatment at temperatures above 1400℃,the high-temperature creep resistance of the fibers is significantly enhanced due to growth of β-SiC grains.This study offers valuable theoretical insights into high-temperature applications of second-generation fibers,contributing to an enhanced understanding of their performance under extreme conditions. 展开更多
关键词 Shicolon-ⅡSiC fiber heat treatment mechanical property MICROSTRUCTURE
在线阅读 下载PDF
Deformation Behavior and Mechanisms of fcc High-Entropy Alloys:Insights from Neutron Diffraction
16
作者 Zhao Yanchun Yao Yatao +9 位作者 Zhang Fan Huang Yan Zhang Yibo Lu Zhichao Zhang Qi Fu Xiaoling Wang Anding Zhang Fei Song Wenli Ma Dong 《稀有金属材料与工程》 北大核心 2026年第3期655-664,共10页
The multi-principal element characteristic of high-entropy alloys has revolutionized the conventional alloy design concept of single-principal element,endowing them with excellent mechanical properties.However,owing t... The multi-principal element characteristic of high-entropy alloys has revolutionized the conventional alloy design concept of single-principal element,endowing them with excellent mechanical properties.However,owing to this multi-principal element nature,high-entropy alloys exhibit complex deformation behavior dominated by alternating and coupled deformation mechanisms.Therefore,elucidating these intricate deformation mechanisms remains a key challenge in current research.Neutron diffraction(ND)techniques offer distinct advantages over traditional microscopic methods for characterizing such complex deformation behavior.The strong penetration capability of neutrons enables in-situ,real-time,and non-destructive detection of structural evolution in most centimeter-level bulk samples under complex environments,and ND allows precise characterization of lattice site occupations for light elements,such as C and O,and neighboring elements.This review discussed the principles of ND,experiment procedures,and data analysis.Combining with recent advances in the research about face-centered cubic high-entropy alloy,typical examples of using ND to investigate the deformation behavior were summarized,ultimately revealing deformation mechanisms dominated by dislocations,stacking faults,twinning,and phase transformations. 展开更多
关键词 high-entropy alloys neutron diffraction face centered-cubic structure deformation mechanism
原文传递
Physics-Informed Neural Networks:Current Progress and Challenges in Computational Solid and Structural Mechanics
17
作者 Itthidet Thawon Duy Vo +6 位作者 Tinh QuocBui Kanya Rattanamongkhonkun Chakkapong Chamroon Nakorn Tippayawong Yuttana Mona Ramnarong Wanison Pana Suttakul 《Computer Modeling in Engineering & Sciences》 2026年第2期48-86,共39页
Physics-informed neural networks(PINNs)have emerged as a promising class of scientific machine learning techniques that integrate governing physical laws into neural network training.Their ability to enforce different... Physics-informed neural networks(PINNs)have emerged as a promising class of scientific machine learning techniques that integrate governing physical laws into neural network training.Their ability to enforce differential equations,constitutive relations,and boundary conditions within the loss function provides a physically grounded alternative to traditional data-driven models,particularly for solid and structural mechanics,where data are often limited or noisy.This review offers a comprehensive assessment of recent developments in PINNs,combining bibliometric analysis,theoretical foundations,application-oriented insights,and methodological innovations.A biblio-metric survey indicates a rapid increase in publications on PINNs since 2018,with prominent research clusters focused on numerical methods,structural analysis,and forecasting.Building upon this trend,the review consolidates advance-ments across five principal application domains,including forward structural analysis,inverse modeling and parameter identification,structural and topology optimization,assessment of structural integrity,and manufacturing processes.These applications are propelled by substantial methodological advancements,encompassing rigorous enforcement of boundary conditions,modified loss functions,adaptive training,domain decomposition strategies,multi-fidelity and transfer learning approaches,as well as hybrid finite element–PINN integration.These advances address recurring challenges in solid mechanics,such as high-order governing equations,material heterogeneity,complex geometries,localized phenomena,and limited experimental data.Despite remaining challenges in computational cost,scalability,and experimental validation,PINNs are increasingly evolving into specialized,physics-aware tools for practical solid and structural mechanics applications. 展开更多
关键词 Artificial Intelligence physics-informed neural networks computational mechanics bibliometric analysis solid mechanics structural mechanics
在线阅读 下载PDF
Mechanistic insights into H_(2)and CO interactions with Fe_(3)O_(4)(111)surface:A computational study for hydrogen-based direct reduction process
18
作者 Xicai Liu Jue Tang +3 位作者 Mansheng Chu Zichuan Zhao Jinge Feng Jie Liu 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期191-203,共13页
The novel process of hydrogen-based shaft furnaces(HSFs)has attracted considerable attention because of their significant reduction of CO_(2)emissions.In this study,the interaction of H_(2)and CO with Fe_(tet1)-and Fe... The novel process of hydrogen-based shaft furnaces(HSFs)has attracted considerable attention because of their significant reduction of CO_(2)emissions.In this study,the interaction of H_(2)and CO with Fe_(tet1)-and Fe_(oct2)-terminated Fe_(3)O_(4)(111)surfaces under HSF conditions,including their adsorption and reduction behaviors,was investigated using the density functional theory method.The results indicated that the H_(2)molecule adsorbed onto the Fe_(tet1)-terminated surface with an adsorption energy(AE)of-1.36 eV,whereas the CO molecule preferentially adsorbed on the Fe_(oct2)-terminated surface with an AE of-1.56 eV.Both H_(2)and CO can readily undergo reduction on the Fe_(tet1)-terminated surface(corresponding to energy barriers of 0.83 eV and 2.23 eV,respectively),but kinetically the reaction of H2is more favorable than that of CO.With regard to the thermodynamics at 400-1400 K,the H_(2)was easy to be adsorbed,while the CO would like to react on the Fe_(tet1)-terminated surface.These thermodynamically tendencies were reversed on the Fe_(oct2)-terminated surface.The thermodynamic disadvantage of the reaction of H_(2)on the Fe_(tet1)-terminated surface was offset by an increase in the temperature.Furthermore,the adsorption of H2 and CO on the Fe_(tet1)-terminated surface was competitive,whereas the adsorption of them on the Fe_(oct2)-terminated surface was synergistic.Therefore,iron ores with a higher proportion of Fe_(tet1)-terminated surface can be applied for the HSF process.In conjunction with the increases in the reduction temperature and the ratio of H_(2)in the reducing gas would promote efficient HSF smelting.These observations provide effective guidance for optimizing the practical operation parameters and advancing the development of the HSF process. 展开更多
关键词 hydrogen-based shaft furnace MAGNETITE density functional theory reaction mechanism coupling mechanism
在线阅读 下载PDF
Regulatory T cells in neurological disorders and tissue regeneration:Mechanisms of action and therapeutic potentials 被引量:1
19
作者 Jing Jie Xiaomin Yao +5 位作者 Hui Deng Yuxiang Zhou Xingyu Jiang Xiu Dai Yumin Yang Pengxiang Yang 《Neural Regeneration Research》 2026年第4期1277-1291,共15页
Regulatory T cells,a subset of CD4^(+)T cells,play a critical role in maintaining immune tolerance and tissue homeostasis due to their potent immunosuppressive properties.Recent advances in research have highlighted t... Regulatory T cells,a subset of CD4^(+)T cells,play a critical role in maintaining immune tolerance and tissue homeostasis due to their potent immunosuppressive properties.Recent advances in research have highlighted the important therapeutic potential of Tregs in neurological diseases and tissue repair,emphasizing their multifaceted roles in immune regulation.This review aims to summarize and analyze the mechanisms of action and therapeutic potential of Tregs in relation to neurological diseases and neural regeneration.Beyond their classical immune-regulatory functions,emerging evidence points to non-immune mechanisms of regulatory T cells,particularly their interactions with stem cells and other non-immune cells.These interactions contribute to optimizing the repair microenvironment and promoting tissue repair and nerve regeneration,positioning non-immune pathways as a promising direction for future research.By modulating immune and non-immune cells,including neurons and glia within neural tissues,Tregs have demonstrated remarkable efficacy in enhancing regeneration in the central and peripheral nervous systems.Preclinical studies have revealed that Treg cells interact with neurons,glial cells,and other neural components to mitigate inflammatory damage and support functional recovery.Current mechanistic studies show that Tregs can significantly promote neural repair and functional recovery by regulating inflammatory responses and the local immune microenvironment.However,research on the mechanistic roles of regulatory T cells in other diseases remains limited,highlighting substantial gaps and opportunities for exploration in this field.Laboratory and clinical studies have further advanced the application of regulatory T cells.Technical advances have enabled efficient isolation,ex vivo expansion and functionalization,and adoptive transfer of regulatory T cells,with efficacy validated in animal models.Innovative strategies,including gene editing,cell-free technologies,biomaterial-based recruitment,and in situ delivery have expanded the therapeutic potential of regulatory T cells.Gene editing enables precise functional optimization,while biomaterial and in situ delivery technologies enhance their accumulation and efficacy at target sites.These advancements not only improve the immune-regulatory capacity of regulatory T cells but also significantly enhance their role in tissue repair.By leveraging the pivotal and diverse functions of Tregs in immune modulation and tissue repair,regulatory T cells–based therapies may lead to transformative breakthroughs in the treatment of neurological diseases. 展开更多
关键词 demyelinating diseases gene editing immune regulation immune tolerance neural regeneration neurological diseases non-immune mechanisms regulatory T cells stem cells STROKE tissue homeostasis tissue repair
暂未订购
上一页 1 2 250 下一页 到第
使用帮助 返回顶部