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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1573-1594页

作者： Zhenliang hu Xueyang zhang Xianfang li School of Civil Engineering University of South ChinaHengyang 421001Hunan ProvinceChina School of Civil Engineering Central South UniversityChangsha 410075China

This paper investigates the bending fracture problem of a micro/nanoscale cantilever thin plate with surface energy,where the clamped boundary is partially debonded along the thickness *** fundamental mechanical equations for the bending problem of micro/nanoscale plates are given by the Kirchhoff theory of thin plates,incorporating the Gurtin-Murdoch surface elasticity *** two typical cases of constant bending moment and uniform shear force in the debonded segment,the associated problems are reduced to two mixed boundary value *** solving the resulting mixed boundary value problems using the Fourier integral transform,a new type of singular integral equation with two Cauchy kernels is obtained for each case,and the exact solutions in terms of the fundamental functions are determined using the PoincareBertrand *** elastic fields near the debonded tips including the bending moment,effective shear force,and bulk stress components exhibit the oscillatory *** dependence relations among the singular fields,the material constants,and the plate's thickness are analyzed for partially debonded cantilever *** surface energy is neglected,these results reduce the bending fracture of a macroscale partially debonded cantilever plate,which has not been previously reported.

关键词： micro/nanoscale cantilever plate partially debonded bending fracture singular integral equation oscillatory singularity

Fracture mechanism of inclusions in thick plate center under tensile loading

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Journal of Iron and Steel Research International 2024年第5期31卷 1196-1209页

作者： Lei hu li-qin zhang Feng hu Guo-hong zhang Kuan Zheng Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan430081HubeiChina Department of Applied Physics Wuhan University of Science and TechnologyWuhan430081HubeiChina Analysis and Testing Center Wuhan University of Science and TechnologyWuhan430081HubeiChina

Segregation of solute atoms in the center of thick plates of the tempered steel can cause an inhomogeneous structural transformation and generate micron-sized inclusions,which leads to lamellar tearing of thick plate and decreases the plasticity and *** formation and fragmentation mechanisms of micron-sized inclusions,like MnS and(Nb,Ti)C,in the center of thick plates were investigated by using thermodynamic calculations,finite element simulations,and electron backscatter diffraction characterization *** results show that micron-sized inclusions nucleate and grow in the liquid phase,and under tensile loading,they exhibit three fragmentation *** local stress during the fragmentation of inclusions is lower than the critical fracture stress of adjacent grains,and phase boundaries can effectively impede crack propagation into the *** existence of a low proportion of high-angle grain boundaries(58.1%)and high Kernel average misorientation value(0.534°)in the segregation band promotes inclusions fragmentation and crack *** difference in crack initiation and propagation direction caused by the morphology of inclusions and physical properties,as well as different matrix arrest abilities,is the main reasons for the diversity of inclusion fragmentation.

关键词： Thick plate Inclusion Finite element simulation Critical fracture stress Fracture mechanism

Investigation of electrostatically tunable adhesion and instability of flying head slider

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Friction 2024年第3期12卷 462-473页

作者： Fan zhang Yu WANG Yueqiang hu Mingquan zhang Baotong li School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China National Engineering Research Center for High Efficiency Grinding College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

The interfacial adhesion between microstructures is inevitable in a micro-electro-mechanical system(e.g.,hard disk drive(HDD)),which may lead to complicated microtribodynamics *** research has investigated the effect of surface potential on the interfacial adhesion and microtribodynamics of the head–disk interface(HDI)in an HDD.A dynamic continuum surface force model,where the electrowetting is considered,is proposed to evaluate the interfacial interaction,and then employed into a two-degree-of-freedom(2DOF)model to theoretically analyze the potential influence mechanism on the *** results confirm that the elimination of potential can effectively repress the adhesion retention,which is further proved by the measured slider response with a laser Doppler vibrometer(LDV).Moreover,the effect of the potential on the adhesion-induced instability is also analyzed through the phase *** tells that the critical stable flying height can be lowered with the elimination of potential.

关键词： electric field(EF) retention instability adhesion

Highly active copper-intercalated weakly crystallized δ-MnO_(2) for low-temperature oxidation of CO in dry and humid air

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 127-136页

作者： Hao zhang huinan li Pengyi zhang Tingxia hu Xianjie Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Beijing Key Laboratory for Indoor Air Quality Evaluation and Control Beijing100084China Midea Corporate Research Center Foshan528311China

Copper intercalated birnessite MnO_(2)(δ-MnO_(2))with weak crystallinity and high specific surface area(421 m^(2)/g)was synthesized by a one-pot redox method and investigated for low-temperature CO *** molar ratio of Cu/Mn was as high as 0.37,which greatly weakened the Mn-O bond and created a lot of low-temperature active oxygen *** situ DRIFTS revealed strong bonding of copper ions with ***-synthesized MnO_(2)-150Cu achieved 100%conversion of 250 ppm CO in normal air(3.1 ppm H_(2)O)even at−10°C under the weight-hourly space velocity(WHSV)of 150 L/(g·h).In addition,it showed high oxygen storage capacity to oxidize CO in inert *** the concurrent moisture in air significantly inhibited CO adsorption and its conversion at ambient temperature,MnO_(2)-150Cu could stably convert CO in 1.3%moisture air at 70°C owing to its great low-temperature activity and reduced competitive adsorption of water with increased *** study discovers the excellent low-temperature activity of weakly crystallized δ-MnO_(2) induced by high content intercalated copper ions.

关键词： CO oxidation Birnessite Interlayer copper Low-temperature Oxygen storage capacity

An analytical model of hot rolling force for a thick plate by combining globally optimal approximation yield criterion and egg-circular velocity field

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Journal of Iron and Steel Research International 2024年第3期31卷 647-659页

作者： Shun-hu zhang Yi zhang Wen-hao Tian Yan li Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

For the sake of solving the problem that it is difficult to be integrated for the Mises specific plastic power due to its nonlinearity,a new linear criterion,named the globally optimal approximation criterion,is constructed by the polygonal approximation to the Mises *** new criterion is proved to be the linear function of the principal stress componentsσ1,σ2 andσ3 and the trajectory of it on theπ-plane is a non-equiangular but equilateral dodecagon intersecting the Mises *** theoretical results of the current criterion described by the Lode stress parameters are in excellent accordance with the experimental ***,according to the trend that the metallic flow velocity between rollers aggrandizes gradually from the inlet to the outlet during the hot rolling of a thick plate,a biomimetic velocity field is proposed in which the horizontal velocity component fits the egg-circular curve *** velocity field and its simulated results agree quite ***,using the determined linear criterion,energy analysis of the constructed velocity field is utilized to obtain the interior deformation power,while the vector decomposition approach is utilized to obtain the frictional power and shear *** this basis,the overall power is obtained and the analytical solutions are generated for the rolling torque,rolling force and the coefficient of the stress state under different egg curves by minimizing the neutral ***,the parameter optimization of the characteristic parameterρwhich affects the slope of the egg-circular curve is carried out and the best egg-circular curve which can minimize the energy consumption is *** best agreement between the theoretical and observed values of rolling force and rolling torque is under this curve,and the mean relative errors of the rolling torque and rolling force are no more than 2.93%,while the maximum error is no more than 8.35%.

关键词： Yield criterion Plastic deformation Rolling force Velocity field Analytical solution

Crosstalk among mitophagy,pyroptosis,ferroptosis,and necroptosis in central nervous system injuries

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Neural Regeneration Research 2024年第8期19卷 1660-1670页

作者： li zhang Zhigang hu Zhenxing li Yixing lin Department of Neurosurgery Jinling HospitalSchool of MedicineNanjing UniversityNanjingJiangsu ProvinceChina

Central nervous system injuries have a high rate of resulting in disability and mortality;however,at present,effective treatments are *** cell death,which is a genetically determined fo rm of active and ordered cell death with many types,has recently attra cted increasing attention due to its functions in determining the fate of cell survival.A growing number of studies have suggested that programmed cell death is involved in central nervous system injuries and plays an important role in the progression of brain *** this review,we provide an ove rview of the role of programmed cell death in central nervous system injuries,including the pathways involved in mitophagy,pyroptosis,ferroptosis,and necroptosis,and the underlying mechanisms by which mitophagy regulates pyroptosis,ferroptosis,and necro *** also discuss the new direction of therapeutic strategies to rgeting mitophagy for the treatment of central nervous system injuries,with the aim to determine the connection between programmed cell death and central nervous system injuries and to identify new therapies to modulate programmed cell death following central nervous system *** conclusion,based on these properties and effects,interventions targeting programmed cell death could be developed as potential therapeutic agents for central nervous system injury patients.

关键词： central nervous system injuries death pyroptosis ferroptosis inflammation mitophagy necroptosis programmed cell

Enhancing Relational Triple Extraction in Specific Domains:Semantic Enhancement and Synergy of Large Language Models and Small Pre-Trained Language Models

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Computers, Materials & Continua 2024年第5期79卷 2481-2503页

作者： Jiakai li Jianpeng hu Geng zhang School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai201620China

In the process of constructing domain-specific knowledge graphs,the task of relational triple extraction plays a critical role in transforming unstructured text into structured *** relational triple extraction models facemultiple challenges when processing domain-specific data,including insufficient utilization of semantic interaction information between entities and relations,difficulties in handling challenging samples,and the scarcity of domain-specific *** address these issues,our study introduces three innovative components:Relation semantic enhancement,data augmentation,and a voting strategy,all designed to significantly improve the model’s performance in tackling domain-specific relational triple extraction *** first propose an innovative attention interaction *** method significantly enhances the semantic interaction capabilities between entities and relations by integrating semantic information fromrelation ***,we propose a voting strategy that effectively combines the strengths of large languagemodels(LLMs)and fine-tuned small pre-trained language models(SLMs)to reevaluate challenging samples,thereby improving the model’s adaptability in specific ***,we explore the use of LLMs for data augmentation,aiming to generate domain-specific datasets to alleviate the scarcity of domain *** conducted on three domain-specific datasets demonstrate that our model outperforms existing comparative models in several aspects,with F1 scores exceeding the State of the Art models by 2%,1.6%,and 0.6%,respectively,validating the effectiveness and generalizability of our approach.

关键词： Relational triple extraction semantic interaction large language models data augmentation specific domains

A new integrated model of deformation resistance and its application in prediction of rolling force of a thick plate

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Journal of Iron and Steel Research International 2024年第4期31卷 882-893页

作者： Shun-hu zhang Yan li li-zhi Che Wen-hao Tian Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

The prediction accuracy of existing models of the rolling force of a thick plate is always very *** address this problem,a high-precision genetic algorithm-backpropagation network(GA-BP)model of deformation resistance was built,and its integration with the traditional fitted model was further ***,a novel rolling force model was obtained by embedding the integration model of deformation resistance in the original model of rolling *** to this research idea,the industrial data are normalized at *** this basis,the interactions among the process parameters were disclosed through the variance analysis,and then described by various virtual *** factors are set as part of input ***,the optimal structure of the GA-BP model of deformation resistance was determined and an integration model of deformation resistance was ***,a novel rolling force model is obtained by substituting the traditional fitted deformation resistance into the Sims model with the integration model of the deformation *** results proves that the introduction of virtual factors can increase the hit rate of±5%from 75.8%to 78%and can reduce the root mean square error from 4.72%to 4.48%.Besides,it is found that the mean relative error of the traditional fitted deformation resistance is 0.142,while that of the modified deformation resistance is only *** addition,the mean relative error in the original rolling force model is 0.145,while that of the present model is only 0.03.

关键词： Integration model-Deformation resistance Variance analysis Virtual factor Genetic algorithm-backpropagation network model

Evidence of ancient rock-ice avalanches along the China-Bhutan Chomolhari Range,and their implications for demise of the summit

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Journal of Mountain Science 2024年第9期21卷 2876-2890页

作者： hu Kaiheng zhang Qiyuan li Pu zhang Xiaopeng liU Shuang li Hao Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China University of Chinese Academy of Sciences Beijing 100149China

Large-scale rock-ice avalanches resulting from the interaction of tectonics and climate are characterized with high mobility,huge volumes of sediment,and rapid denudation,being a major agent of landscape evolution in high altitude mountainous ***,the extreme glaciated slope failures often transform into extraordinarily large and mobile debris flows,resulting in disastrous consequences such as sedimentation and *** to a dearth of on-site observation data and experimental data collection,our comprehension of the geomorphic and kinematic characteristics of rock-ice avalanches remains *** we report a cluster of ancient rock-ice avalanches spreading along the Chomolhari range of the China-Bhutan *** integrating remote sensing image interpretation with detailed field investigations,we demonstrate the geomorphic and sedimentary characteristics of four events among the *** estimated volumes of the four are 23.73 Mm³,39.69 Mm³,38.43 Mm³,and 38.25 Mm³,*** presence of pre-existing moraines or alluvial fans constrained their movement,resulting in deposition features such as marginal digitated lobes at higher elevations and large depressed areas in the *** the Savage-hutter theory,we calculate the basal friction angle and travel angle of these ancient rock-ice avalanches that are both less than 10°,affirming the similarity of these avalanches in the study area to those occurring in other *** study significantly contributes to understanding the geomorphic and kinematic characteristics of rock-ice avalanches in high-altitude mountainous regions,providing valuable insights into their response to the disproportionate growth of Himalayan peaks.

关键词： Rock-ice avalanche Himalayas Southern Yadong-Gulu rift Vertical slip-rate Landscape evolution

A Facile li_(2)TiO_(3) Surface Modification to Improve the Structure Stability and Electrochemical Performance of Full Concentration Gradient li-Rich Oxides

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Energy & Environmental Materials 2024年第3期7卷 41-48页

作者： Naifang hu Yuan Yang lin li Yuhan zhang Zhiwei hu Lan zhang Jun Ma Guanglei Cui Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101China Institute of Materials Science and Engineering Ocean University of ChinaQingdao 266100China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China Max Planck Institute for Chemical Physics of Solids Nothnitzer Strasse 40Dresden D-01187Germany CAS Key Laboratory of Green Process and Engineering Beijing Key Laboratory of Ionic Liquids Clean ProcessState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Shandong Energy Institute Qingdao 266101China

Full concentration gradient lithium-rich layered oxides are catching lots of interest as the next generation cathode for lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rate performance,whereas the high lithium residues on its surface impairs the structure stability and long-term cycle ***,a facile multifunctional surface modification method is implemented to eliminate surface lithium residues of full concentration gradient lithium-rich layered oxides by a wet chemistry reaction with tetrabutyl titanate and the post-annealing *** realizes not only a stable li_(2)TiO_(3)coating layer with 3D diffusion channels for fast li^(+)ions transfer,but also dopes partial Ti^(4+)ions into the sub-surface region of full concentration gradient lithium-rich layered oxides to further strengthen its crystal ***,the modified full concentration gradient lithium-rich layered oxides exhibit improved structure stability,elevated thermal stability with decomposition temperature from 289.57℃to 321.72℃,and enhanced cycle performance(205.1 mAh g^(-1)after 150 cycles)with slowed voltage drop(1.67 mV per cycle).This work proposes a facile and integrated modification method to enhance the comprehensive performance of full concentration gradient lithium-rich layered oxides,which can facilitate its practical application for developing higher energy density lithium-ion batteries.

关键词： full concentration gradient lithium-rich layered oxides structure stability surface modification