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Analysis and optimization of stamping and forming process of bearing outer ring

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 227-237页

作者： Shichao Zhu Yulu Ding bing Long Hun guo Linhan Ouyang Wengang Chen Zhengyi Jiang College of Aeronautics and Mechanical Engineering Changzhou Institute of TechnologyChangzhou 213002China College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China eering University of WollongongWollongong NSW 2522Australia

To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators such asforming limits,thickness distribution,and principal strains in the forming process in ***-dimensionalmodels of the concave and convex dies were *** effects of different process parameters,includingstamping speed,edge pressure,sheet metal thickness,and friction coefficient,on the quality of the forming partswere investigated by varying these ***,the orthogonal experimental method was used todetermine an optimal experimental group from multiple sets of *** was found that under the processparameters of a stamping speed of 3000 mm/s,edge pressure of 2000 N,sheet metal thickness of 0.9 mm,andfriction coefficient of 0.125,the forming quality of the outer ring of the bearing is ideal.

关键词： Plate stamping Bearing outer ring Mold design Optimization

Surface and structure engineering of MXenes for rechargeable batteries beyond lithium

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Journal of Materiomics 2024年第1期10卷 253-268页

作者： Zefu Huang Majid Farahmandjou Frederick Marlton Xin guo Hong Gao bing Sun guoxiu Wang Centre for Clean Energy Technology School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyUltimoNSW2007Australia Joint International Laboratory on Environmental and Energy Frontier Materials School of Environmental and Chemical Engineering Shanghai UniversityShanghai200444China

With the rapid growth in renewable energy,researchers worldwide are trying to expand energy storage *** development of beyond-lithium battery technologies has accelerated in recent years,amid concerns regarding the sustainability of battery ***,the absence of suitable high-performance materials has hampered the development of the next-generation battery ***,a family of 2D transition metal carbides and/or nitrides,have drawn significant attention recently for electrochemical energy storage,owing to their unique physical and chemical *** extraordinary electronic conductivity,compositional diversity,expandable crystal structure,superior hydrophilicity,and rich surface chemistries make MXenes promising materials for electrode and other components in rechargeable *** report especially focuses on the recent MXene applications as novel electrode materials and functional separator modifiers in rechargeable batteries beyond *** particular,we highlight the recent advances of surface and structure engineering strategies for improving the electrochemical performance of the MXene-based materials,including surface termination modifications,heteroatom doping strategies,surface coating,interlayer space changes,nanostructure engineering,and heterostructures and secondary materials ***,perspectives for building future sustainable rechargeable batteries with MXenes and MXene-based composite materials are presented based upon material design and a fundamental understanding of the reaction mechanisms.

关键词： MXenes Energy storage materials 2D materials Surface engineering Structure engineering

Identification of FIR systems under difference-driven scheduled quantized observations

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Control Theory and Technology 2024年第2期22卷 163-172页

作者： Dong Liang Ruizhe Jia Fengwei jing Yong Song jin guo School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Knowledge Automation for Industrial Processes Ministry of EducationBeijing100083China National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing100083China

In networked system identification,how to effectively use communication resources and improve convergence speed is the focus of ***,there is an inherent contradiction between the two *** this paper,the event-driven communication is used to save communication resources for the identification of finite impulse response systems,and the input design is carried out to meet the requirements of convergence ***,a difference-driven communication is ***,the performance of the communication mechanism is analyzed,and the calculation method of its communication rate is *** that,according to the communication rate and the convergence rate of the identification algorithm,the input design problem is transformed into a constrained optimization problem,and the algorithm for finding the optimal solution is *** addition,considering the case that the output is quantized by multiple thresholds,the way to calculate its communication rate is given and the influence of threshold number on communication rate is ***,the effectiveness of the algorithm is verified by simulation.

关键词： System identification FIR system Difference-driven Quantized observation

Vulnerability assessment of UAV engine to laser based on improved shotline method

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Defence Technology（防务技术） 2024年第3期33卷 588-600页

作者： Le Liu Chengyang Xu Changbin Zheng Sheng Cai Chunrui Wang jin guo Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100049China

Laser anti-drone technology is entering the sequence of actual combat,and it is necessary to consider the vulnerability of typical functional parts of *** the concept of"vulnerability"was proposed,a variety of analysis programs for battlefield targets to traditional weapons have been developed,but a comprehensive assessment methodology for targets'vulnerability to laser is still *** on the shotline method,this paper proposes a method that equates laser beam to shotline array,an efficient vulnerability analysis program of target to laser is established by this method,and the program includes the circuit board and the wire into the vulnerability analysis category,which improves the precision of the vulnerability *** the UAV engine part as the target of vulnerability analysis,combine with the"life-death unit method"to calculate the laser penetration rate of various materials of the UAV,and the influence of laser weapon system parameters and striking orientation on the killing probability is quantified after introducing the penetration rate into the vulnerability analysis *** quantitative analysis method proposed in this paper has certain general expansibility,which can provide a fresh idea for the vulnerability analysis of other targets to laser.

关键词： Laser weapon Laser damage Vulnerability UAV Engine Killing probability

An integrated portable bio-monitoring system based on tough hydrogels for comprehensive detection of physiological activities

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Nano Research 2024年第1期17卷 321-332页

作者： Congcong Yang Chenchen Ji Fengjiao guo Chunjiang jin Hongyu Mi Zhongchang Wang State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources School of Chemical Engineering and TechnologyXinjiang UniversityUrumqi 830017China International Iberian Nanotechnology Laboratory(INL) Avenide Mestre Jose VeigaBraga 4715-330Portugal

Advanced soft ion-conducting hydrogels have been developed rapidly in the integrated portable health monitoring equipment due to their higher sensitivity,sensory traits,tunable conductivity,and stretchability for physiological activities and personal healthcare ***,traditional hydrogel conductors are normally susceptible to large deformation and strong mechanical stress,which leads to inferior electro-mechanical stability for real application ***,a strong ionically conductive hydrogel(poly(vinyl alcohol)-boric acid-glycerol/sodium alginate-calcium chloride/electrolyte ions(PBG/SC/EI))was designed by engineering the covalently and ionically crosslinked networks followed by the salting-out effect to further enhance the mechanical strength and ionic conductivity of the *** to the collective effects of the energy-dissipation mechanism and salting-out effect,the designed PBG/SC/EI with excellent structural integrity and robustness exhibits exceptional mechanical properties(elongation at break for 559.1%and tensile strength of 869.4 kPa)and high ionic conductivity(1.618 S·m^(-1)).As such,the PBG/SC/EI strain sensor features high sensitivity(gauge factor=2.29),which can effectively monitor various kinds of human motions(joint motions,facial micro-expression,faint respiration,and voice recognition).Meanwhile,the hydrogel-based Zn||MnO_(2)battery delivers a high capacity of 267.2 mAh·g^(-1)and a maximal energy density of 356.8 Wh·kg^(-1)associated with good cycle performance of 71.8%capacity retention after 8000 ***,an integrated bio-monitoring system with the sensor and Zn||MnO_(2)battery can accurately identify diverse physiological activities in a real-time and non-invasive *** work presents a feasible strategy for designing high-performance conductive hydrogels for highly-reliable integrated bio-monitoring systems with excellent practicability.

关键词： Ionically conductive hydrogel strain sensor Zn-based battery integrated bio-monitoring system human motion monitoring

Patient-derived induced pluripotent stem cells with a MERTK mutation exhibit cell junction abnormalities and aberrant cellular differentiation potential

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World Journal of Stem Cells 2024年第5期16卷 512-524页

作者： Hang Zhang Ling-Zi Wu Zhen-Yu Liu Zi-bing jin Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing 100730China

BACKGROUND Human induced pluripotent stem cell(hiPSC)technology is a valuable tool for generating patient-specific stem cells,facilitating disease modeling,and invest-igating disease ***,iPSCs carrying specific mutations may limit their clinical applications due to certain inherent *** To investigate the impact of MERTK mutations on hiPSCs and determine whether hiPSC-derived extracellular vesicles(EVs)influence anomalous cell junction and differentiation *** We employed a non-integrating reprogramming technique to generate peripheral blood-derived hiPSCs with and hiPSCs without a MERTK ***-somal karyotype analysis,flow cytometry,and immunofluorescent staining were utilized for hiPSC *** and proteomics were employed to elucidate the expression patterns associated with cell junction abnormalities and cellular differentiation ***,EVs were isolated from the supernatant,and their RNA and protein cargos were examined to investigate the involvement of hiPSC-derived EVs in stem cell junction and *** The generated hiPSCs,both with and without a MERTK mutation,exhibited normal karyotype and expressed pluripotency markers;however,hiPSCs with a MERTK mutation demonstrated anomalous adhesion capability and differentiation potential,as confirmed by transcriptomic and proteomic ***,hiPSC-derived EVs were involved in various biological processes,including cell junction and *** HiPSCs with a MERTK mutation displayed altered junction characteristics and aberrant differentiation ***,hiPSC-derived EVs played a regulatory role in various biological processes,including cell junction and differentiation.

关键词： Cell junction Cellular differentiation Extracellular vesicle Human induced pluripotent stem cells Transcriptomics Proteomics

Stereoselective Self-Assembly of Chiral Metalla[2]Catenanes and Lemniscular Macrocycles

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CCS Chemistry 2024年第8期6卷 2000-2010页

作者： Shu-jin Bao Hai-Ning Zhang guo-Xin jin Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of PolymersDepartment of ChemistryFudan UniversityShanghai 200433

Designing and stereoselectively constructing chiral mechanically interlocked molecules(MIMs)is a goal that many chemists are pursuing due to their potential in the development of functional molecular machines involved in catalysis,sensing,and chiroptical ***,the synthesis of enantiopure supramolecular entities with crystallographic structures remains ***,the stereoselective self-assembly of chiral metalla[2]catenanes interlocked by two D-shaped macrocycles was realized by combining long binuclear half-sandwich organometallic Cp*Rh^(III)(Cp*=η^(5)-pentamethylcyclopentadienyl)clip and ditopic monodentate ligand incorporating L-leucine *** resulting metalla[2]catenane displayed unique co-conformational mechanical helical chirality characteristics arising from the chirality transfer of the chiral ***,decreasing the length of the binuclear Cp*Rh^(III)clip and adjusting the steric hindrance of the amino-acid side chains(L-alanine and L-phenylalanine)in the ligands resulted in two lemniscular macrocycles with left-handed(M)-twisted conformational *** the best of our knowledge,the synthesized macrocycles are the first family of homochiral abnormal lemniscate-shaped organometallic macrocycles featuring figure-eight ***[2]catenanes and macrocycles with opposite chirality were also generated by employing corresponding D-amino acid ligands,as evidenced by single-crystal X-ray diffraction,nuclear magnetic resonance,mass,and circular dichroism *** present study demonstrates that homochiral MIMs can be accessed readily using amino acid–containing ligands through rational molecular design.

关键词： stereoselective synthesis chirality metallacatenanes twisted macrocycles aminoacid residues

Changes of nutrients and microbial communities in recovery process of abandoned rare earth tailings

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Pedosphere 2024年第4期34卷 826-836页

作者： bing ZHANG Junli WU Mengyuan HUANG Yan ZHANG jin ZHAO Chuntao HE Zhongyi YANG School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510006China School of Life Sciences Sun Yat-sen UniversityGuangzhou 510275China School of Agriculture State Key Laboratory for BiocontrolShenzhen Campus of Sun Yat-sen UniversitySun Yat-sen UniversityShenzhen 518107China

Rare earth element(REE)mining has wrought severe ecosystem destruction,particularly in the loss of carbon(C),nitrogen(N),and phosphorus(P).Furthermore,its effects on nutrient recovery characteristics and associated microbial abundance are still poorly *** this study,an investigation was conducted to determine C,N,and P recovery patterns and microbial communities in abandoned REE mining tailings with different abandoned durations of 1.5(1.5-Y),7(7-Y),10(10-Y),and 14(14-Y)years and at an unmined site(the control group)in Jiangxi Province,*** tailing delamination at each site was investigated in 0–15(layer 1)and 15–30(layer 2)cm tailing *** the abandoned duration of REE tailings,C and P in layer 1 continued to recover from 1.62 to 8.51 g kg^(-1) and from 0.71 to 1.94 g kg^(-1),respectively;N losses of 0.60 and 0.22 g kg^(-1) occurred at the 1.5-Y and 10-Y sites,while N in layer 1 slightly increased at the 14-Y ***,Methylosinus,Bradyrhizobium,Pseudomonas,and Azospirillum were dominant bacteria at the 14-Y site and in the *** relative abundances of N-fixing bacteria Mesorhizobium(32.94%),Sinorhizobium(0.24%),Frankia(0.71%),and Burkholderia(2.38%)at the 14-Y site were 1.33–3.97 times those in the control(24.19%,0.18%,0.32%and 0.60%,respectively),which was helpful for tailing N *** the 14-Y site,Tylospora(50.24%),Luellia(11.02%),Tomentella(6.94%),and Chaetomium(4.34%)were the dominant fungal genera,while Tylospora(56.93%),Suillus(11.45%),and Penicillium(6.78%)predominated in the *** relative abundance of the P-dissolving fungus Aspergillus at the 14-Y site(0.42%)was 4.2 times that in the control(0.1%),which may lead to the improved tailing P *** the 14-Y site,woody plants such as Pinus massoniana and native pioneering herbs and ferns such as Dicranopteris dichotoma and Nephrolepis auriculata probably invaded from adjacent *** study unraveled the natural restoration of plant and micro

关键词： abandoned duration mining tailing N-fixing bacteria nutrient recovery P-solubilizing fungi rare earth element

Amorphous electrocatalysts for urea oxidation reaction

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Progress in Natural Science:Materials International 2024年第2期34卷 362-375页

作者： Fenghui guo Dongle Cheng Qian Chen Hao Liu Zhiliang Wu Ning Han bing-Jie Ni Zhijie Chen School of Materials Science and Technology China University of Geosciences Shenzhen Academy of Metrology and Quality Inspection Centre for Technology in Water and Wastewater School of Civil and Environmental Engineering University of Technology Sydney College of Safety and Environmental Engineering Shandong University of Science and Technology Institute of Yellow River Delta Earth Surface Processes and Ecological Integrity Shandong University of Science and Technology Discipline of Chemical Engineering Western Australian School of Mines: Minerals Energy and Chemical Engineering Curtin University Department of Materials Engineering School of Civil and Environmental Engineering The University of New South Wales

Electrochemical urea oxidation reaction(UOR) is a promising alternative to oxygen evolution reaction(OER) for realizing energy-saving hydrogen production. Developing efficient electrocatalysts for UOR becomes a central challenge. Recently, amorphous materials have been extensively used as UOR catalysts because of their numerous defective sites and flexible electronic properties. In this review, recent advancements in the development of amorphous UOR electrocatalysts are analyzed. The UOR mechanism is discussed, and the design of amorphous catalysts is then analyzed. The main catalyst design strategies are illustrated, including nanostructure control,heteroatom doping, composition regulation, and heterostructure construction. Also, electrocatalysts' structureperformance correlation is interpreted. Perspectives in this field are proposed for guiding future studies on the development of high-performance amorphous catalysts towards energy sustainability.

关键词： Catalyst design Component regulation Heteroatom doping Heterostructures Hydrogen energy