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Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

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Defence Technology（防务技术） 2024年第1期31卷 580-593页

作者： zheng-qing Zhou Ze-chen Du Xiao Wang Hui-ling Jiang Qiang Zhou Yu-long Zhang Yu-zhe liu pei-ze Zhang Research Institute of Macro-Safety Science University of Science and TechnologyBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China School of Mechanical Engineering Nantong UniversityNantong226019China China North Industry Advanced Technology Generalization Institute Beijing100089China China Academy of Ordnance Science China

As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive *** this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were *** the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(SEM) and electron backscattered diffraction(EBSD).The observation result shows that many slip bands(SBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro *** addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the *** stress parameters of the observation points were obtained through an effective numerical *** mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro *** result shows that the generation and expansion of micro defects are related to the stress area(*** upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile ***,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(*** horizontal direction) were also *** was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only SBs and a few micro cracks,and the those decrea

关键词： Explosive load Quasi-cracking area Micro defects Steel plate Dynamic response Numerical simulation

Development of Fixture Layout Optimization for Thin-Walled Parts:A Review

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 15-39页

作者： Changhui liu jing Wang Binghai Zhou Jianbo Yu Ying zheng Jianfeng liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao Shipbuilding Co. Ltd.Shanghai 200137China

An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past ***,few papers systematically review these *** analyzing existing literature,this paper summarizes the process of fixture layout optimization and the methods *** process of optimization is made up of optimization objective setting,assembly variation/deformation modeling,and fixture layout *** paper makes a review of the fixture layout for thin-walled parts according to these three ***,two different kinds of optimization objectives are *** usually consider in-plane variations or out-of-plane deformations when designing ***,modeling methods for assembly variation and deformation are divided into two categories:Mechanism-based and data-based *** common methods are discussed *** that,optimization algorithms are reviewed *** are two kinds of optimization algorithms:Traditional nonlinear programming and heuristic ***,discussions on the current situation are *** research direction of fixture layout optimization in the future is discussed from three aspects:Objective setting,improving modeling accuracy and optimization ***,a new research point for fixture layout optimization is *** paper systematically reviews the research on fixture layout optimization for thin-walled parts,and provides a reference for future research in this field.

关键词： Thin-walled parts Assembly quality Fixture layout optimization Modeling methods Optimization algorithms

Optimization of Fixture Number in Large Thin-Walled Parts Assembly Based on IPSO

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 213-227页

作者： Changhui liu jing Wang Ying zheng Ke Jin Jianbo Yu Jianfeng liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao Shipbuilding Co. Ltd.Shanghai 200137China

There are lots of researches on fixture layout optimization for large thin-walled *** researches focus on the positioning problem,i.e.,optimizing the positions of a constant number of ***,how to determine the number of fixtures is *** most cases,the number of fixtures located on large thin-walled parts is determined based on engineering experience,which leads to huge fixture number and extra ***,this paper constructs an optimization model to minimize the number of *** constraints are set in the optimization model to ensure that the part deformation is within the surface profile *** addition,the assembly gap between two parts is also *** conduct the optimization,this paper develops an improved particle swarm optimization(IPSO)algorithm by integrating the shrinkage factor and adaptive inertia *** the algorithm,particles are encoded according to the fixture *** dimension of the particle is assigned to a sub-region by constraining the optional position range of each fixture to improve the optimization ***,a case study on ship curved panel assembly is provided to prove that our method can optimize the number of fixtures while meeting the assembly quality *** research proposes a method to optimize the number of fixtures,which can reduce the number of fixtures and achieve deformation control at the same time.

关键词： Assembly quality Large thin-walled parts Fixture layout PSO FEM

Conversion of magnetron-sputtered sacrificial intermediate layer into a stable FeCo-LDH catalyst for oxygen evolution reaction

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Nano Research 2024年第5期17卷 4307-4313页

作者： Zhiquan lang Guang-ling Song Xingpeng Liao Wenzhong Huang Yixing Zhu Haipeng Wang Dajiang zheng Center for Marine Materials Corrosion and Protection College of MaterialsXiamen UniversityXiamen 361005China Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005China The University of Queensland St.LuciaOLD 4072Australia State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

Controllable and scalable preparation of electrocatalyst materials holds significant importance for their practical *** sputtering is a highly effective synthesis method,known for its producing uniform films and allowing easy control of component *** this paper,we propose an in-situ synthesis method for layered double hydroxide(LDH)electrocatalysts through sacrificing magnetron sputtered *** resulting FeCo-LDH catalyst demonstrated a low overpotential of only 300 mV at 10 mA·cm^(-2).Furthermore,we conducted spectroscopic analysis to investigate the surface changes of the catalysts during the oxygen evolution reaction(OER)*** findings indicated that the formation of Co oxyhydroxides plays a beneficial role in enhancing the catalytical performance of the FeCo-LDH for OER *** restructuring strategy of converting a magnetron-sputtered sacrificial film into a catalytical LDH introduces a new avenue to the synthesis of transition metal-based electrocatalysts.

关键词： magnetron co-sputtering surface reconstruction electrocatalyst oxygen evolution reaction

Quantitative trait loci identification reveals zinc finger protein CONSTANS-LIKE 4 as the key candidate gene of stigma color in watermelon(Citrullus lanatus)

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Journal of Integrative Agriculture 2024年第7期23卷 2292-2305页

作者： Shuang pei Zexu Wu Ziqiao Ji zheng liu Zicheng Zhu Feishi Luan Shi liu Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(Northeast Region) Ministry of Agriculture and RuralAffairs/College of Horticulture and Landscape ArchitectureNortheast Agricultural UniversityHarbin 150030China Institute of Rural Revitalization Science and Technology Heilongjiang Academy of Agricultural SciencesHarbin 150028China

Stigma color is a critical agronomic trait in watermelon that plays an important role in ***,there are few reports on the regulation of stigma color in *** this study,a genetic analysis of the F2 population derived from ZXG1553(P1,with orange stigma)and W1-17(P2,with yellow stigma)indicated that stigma color is a quantitative trait and the orange stigma is recessive compared with the yellow *** segregant analysis sequencing(BSA-seq)revealed a 3.75 Mb segment on chromosome 6 that is related to stigma ***,a major stable effective QTL Clqsc6.1(QTL stigma color)was detected in two years between cleaved amplified polymorphic sequencing(CAPS)markers Chr06_8338913 and Chr06_9344593 spanning a~1.01 Mb interval that harbors 51 annotated ***97C06G117020(annotated as zinc finger protein CONSTANS-LIKE 4)was identified as the best candidate gene for the stigma color trait through RNA-seq,quantitative real-time PCR(qRT-PCR),and gene structure alignment analysis among the natural watermelon *** expression level of Cla97C06G117020 in the orange stigma accession was lower than in the yellow stigma accessions with a significant difference.A nonsynonymous SNP site of the Cla97C06G117020 coding region that causes amino acid variation was related to the stigma color variation among nine watermelon accessions according to their re-sequencing *** color formation is often related to carotenoids,and we also found that the expression trend of ClCHYB(annotated asβ-carotene hydroxylase)in the carotenoid metabolic pathway was consistent with Cla97C06G117020,and it was expressed in low amounts in the orange stigma *** data indicated that Cla97C06G117020 and ClCHYB may interact to form the stigma *** study provides a theoretical basis for gene fine mapping and mechanisms for the regulation of stigma color in watermelon.

关键词： watermelon stigma color gene mapping zinc finger protein CONSTANS-LIKE 4

A modified 3D mean strain energy density criterion for predicting shale mixed-mode Ⅰ/Ⅲ fracture toughness

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2411-2428页

作者： Kun zheng Chaolin Wang Yu Zhao jing Bi Haifeng liu College of Civil Engineering Guizhou UniversityGuiyang550025China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic *** edge-notched disk bending(ENDB)specimens are employed to measure the entire range of mixed-modeⅠ/Ⅲfracture toughness of Longmaxi *** theoretically interpret the fracture mechanisms,this research first introduces the detailed derivations of three established fracture *** distinguishing the volumetric and distortional strain energy densities,an improved three-dimensional mean strain energy density(MSED)criterion is *** the critical volumetric to distortional MSED ratio decreases,the transition from tensiondominated fracture to shear-dominated fracture is *** results indicate that both peak load and applied energy increase significantly with the transition from pure mode I(i.e.,tension)to pure modeⅢ(i.e.,torsion or tearing)since mode-Ⅲcracking happens in a twisted manner and mode-Ⅰcracking occurs in a coplanar *** macroscopic fracture signatures are consistent with those of triaxial hydraulic *** average ratio of pure mode-Ⅲfracture toughness to pure mode-Ⅰfracture toughness is 0.68,indicating that the obtained mode-Ⅲfracture resistance for a tensionbased loading system is apparent rather than *** to the three mainstream fracture criteria,the present fracture criterion exhibits greater competitiveness and can successfully evaluate and predict mixed-modeⅠ/Ⅲfracture toughness of distinct materials and loading methods.

关键词： Longmaxi shale Hydraulic fracturing Fracture mechanisms Fracture criteria Mixed-modeⅠ/Ⅲfracture toughness Edge-notched disk bending

Performance Limits and Advancements in Single 2D Transition Metal Dichalcogenide Transistor

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Nano-Micro Letters 2024年第12期16卷 134-188页

作者： jing Chen Ming-Yuan Sun Zhen-Hua Wang zheng Zhang Kai Zhang Shuai Wang Yu Zhang Xiaoming Wu Tian-ling Ren Hong liu Lin Han Institute of Marine Science and Technology Shandong UniversityQingdao 266237ShandongPeople’s Republic of China School of Integrated Circuits and Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084People’s Republic of China BNRist Tsinghua UniversityBeijing 100084People’s Republic of China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100ShandongPeople’s Republic of China Shenzhen Research Institute of Shandong University Shenzhen 518057People’s Republic of China Shandong Engineering Research Center of Biomarker and Artificial Intelligence Application Jinan 250100People’s Republic of China

Two-dimensional(2D)transition metal dichalcogenides(TMDs)allow for atomic-scale manipulation,challenging the conventional limitations of semiconductor *** capability may overcome the short-channel effect,sparking significant advancements in electronic devices that utilize 2D *** the dimension and performance limits of transistors based on 2D TMDs has gained substantial *** review provides a comprehensive investigation into these limits of the single 2D-TMD *** delves into the impacts of miniaturization,including the reduction of channel length,gate length,source/drain contact length,and dielectric thickness on transistor operation and *** addition,this review provides a detailed analysis of performance parameters such as source/drain contact resistance,subthreshold swing,hysteresis loop,carrier mobility,on/off ratio,and the development of p-type and single logic *** review details the two logical expressions of the single 2D-TMD logic transistor,including current and *** also emphasizes the role of 2D TMD-based transistors as memory devices,focusing on enhancing memory operation speed,endurance,data retention,and extinction ratio,as well as reducing energy consumption in memory devices functioning as artificial *** review demonstrates the two calculating methods for dynamic energy consumption of 2D synaptic *** review not only summarizes the current state of the art in this field but also highlights potential future research directions and *** underscores the anticipated challenges,opportunities,and potential solutions in navigating the dimension and performance boundaries of 2D transistors.

关键词： Two-dimensional transistors Dimension limits Performance limits Memory devices Artificial synapses

Nano-bio interactions between 2D nanomaterials and mononuclear phagocyte system cells

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BMEMat(BioMedical Engineering Materials) 2024年第2期2卷 92-117页

作者： jing Zhao zheng Chen Shanbiao liu Pin Li Shiyi Yu Daishun ling Fangyuan Li Institute of Pharmaceutics Hangzhou Institute of Innovative MedicineCollege of Pharmaceutical SciencesZhejiang UniversityHangzhouChina Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringSchool of Biomedical EngineeringNational Center for Translational MedicineShanghai Jiao Tong UniversityShanghaiChina World Laureates Association(WLA)Laboratories ShanghaiChina Key Laboratory of Precision Diagnosis and Treatment for Hepatobiliary and Pancreatic Tumor of Zhejiang Province HangzhouChina Songjiang Institute and Songjiang Hospital Shanghai Jiao Tong University School of MedicineShanghaiChina

Two-dimensional(2D)nanomaterials,known for their unique atomic arrangements and exceptional physicochemical properties,have garnered significant attention in biomedical applications,particularly in the realms of immunotherapy for tissue engineering and tumor *** applications necessitate a thorough assessment of the potential influence of 2D nanomaterials on immune ***,the mononuclear phagocyte system(MPS)cells,which play pivotal roles in both innate and adaptive immunity,are essential for maintaining organismal *** cells with phagocytic capability contribute to the prevention of foreign body invasion and the elimination of dead or senescent ***,MPS cells,including macrophages and dendritic cells,serve as vital bridges between innate and adaptive immune ***,understanding the nano-bio interactions between 2D nanomaterials and MPS cells is *** nano-bio interactions including cellular uptake,cytocompatibility,and immunological impact are invaluable forthe purposeful design of 2D ***,we provide an overview of the latest advancements in understanding the nano-bio interactions between 2D nanomaterials and MPS cells,and discuss the current challenges and future prospects of employing 2D nanomaterials in the field of nanomedicine.

关键词： 2D nanomaterials cellular uptake dendritic cells immunological impact macrophages mononuclear phagocyte system nano-bio interactions

A buffer overflow detection and defense method based on RiSC-V instruction set extension

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Cybersecurity 2024年第2期7卷 28-43页

作者： Chang liu Yan-Jun Wu jing-zheng Wu Chen Zhao Intelligent Software Research Center Institute of SoftwareChinese Academy of SciencesBejingChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijingChina

Buffer overflow poses a serious threat to the memory security of modern operating *** overwrites the con-tents of other memory areas by breaking through the buffer capacity limit,destroys the system execution environ-ment,and provides implementation space for various system attacks such as program control flow *** makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer *** example,No eXecute(NX for short)is a memory management technology commonly used in Harvard *** can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control ***,in recent years,it has also been used in the field of system security,deriving a series of solutions based on NX technology,such as ExecShield,DEP,StackGuard,***,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is *** in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow *** the continuous rapid development of the system architecture,it is urgent to develop defense methods that are applicable to different system application environments and oriented to all executable memory spaces to meet the needs of system security ***,we propose BOP,A new system memory security design method based on RISC-V extended instructions,to build a RISC-V buffer overflow detection and defense system and deal with the buffer overflow threat in *** to this method,NX technology can be combined with program control flow analysis,and Nx bit mechanism can be used to manage the executability of memory space,so as to achieve a more granular detection and defense of buffer overflow attacks that may occur in RISC-V system

关键词： RISc-V Operating system security Buffer overflow Control flow hijacking Nx bit Xibop