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Journal of Materials Science & Technology 2021年第11期70卷 1-11页

作者： Cean Guo Feng Zhou Minghui Chen Jinlong wang Shenglong Zhu Fuhui wang School of Equipment Engineering Shenyang Ligong UniversityShenyang110159China Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang110819China Institute of Metal Research Chinese Academy of SciencesShenyang110016China

NiCrAlY coatings are widely applied on various alloy components to enhance oxidation and/or corrosion resistance at high ***,elements interdiffusion occurs between them due to composition *** various diffusion barriers(DBs)are reported,this problem is still far from completely solved as most ceramic barriers suffer from poor adherence,while the metallic barriers play a limited *** this study,NiCrAlY coating was deposited onto a second-generation single-crystal superalloy by arc ion plating.A novel simple method is provided to address elements *** pre-oxidation at a moderate temperature,a thin scale of Ni(Co)O forms at the alloy *** transforms to be an alumina/NiCoCr alloy/alumina sandwich by an in-situ reaction with the overlaying NiCrAlY coating and the alloy substrate at high service temperatures,which offers good barrier ability in conjunction with strong *** the presence of such an alumina/alloy/alumina DB,the NiCrAlY coating provides high resistance to oxidation and scale spallation for the alloy substrate.

关键词： Superalloys NiCrAlY coating High-temperature oxidation Elements interdiffusion Diffusion barrier

3D multiphysic simulations of energy field and material process in radial ultrasonic rolling electrochemical micromachining

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Chinese Journal of Aeronautics 2022年第3期35卷 494-508页

作者： Minghuan wang Yongchao SHANG Changshun LIU Jiajie wang Jinsong ZHENG Xufeng XU College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023ZhejiangChina Key Laboratory of Special Purpose Equipment and Advanced Processing Technology of Ministry of Education Zhejiang University of TechnologyHangzhou 310023ZhejiangChina

The radial ultrasonic rolling electrochemical micromachining(RUR-EMM)combined rolling electrochemical micromachining(R-EMM)and ultrasonic vibration was studied in this *** fundamental understanding of the machining process especially the interaction between multiphysics in the interelectrode gap(IEG)was investigated and discussed by the finite element *** multiphysics coupling model including flow field model,Joule heating model,material dissolution model and vibration model was built.3D multiphysics simulation based on micro dimples process in RUR-EMM and R-EMM was *** results showed that the electrolyte flowed into and out IEG periodically,gas bubbles were easy to squeeze out and the gas void fraction deceased about 16%to 54%,the maximum current density increased by 1.36 times in RUR-EMM than in R-EMM in one vibration period of *** application of the ultrasonic vibration increased the electrolyte temperature about 1.3–4.4%in *** experiments of the micro dimple process denoted better corrosion consistency of array dimples in RUR-EMM,there was no island at the micro dimple bottom which always formed in R-EMM,and an aggregated deviation of less than 8.7%for the micro dimple depth and 4%for the material removal amount between theory and experiment was obtained.

关键词： 3D Multiphysics simulation Electrochemical micromachining Energy field Material process Micro dimple Ultrasonic vibration

A multifunctional electrolyte additive for zinc-ion capacitors with low temperature resistant and long lifespan

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Journal of Energy Chemistry 2024年第7期94卷 477-485页

作者： Ming Sun Zekai Zhang Shuqing Fu Yifan Zhang Ruoyu wang Hongchun Mu Cheng Lian Wenqiang wang Gengchao wang Shanghai Engineering Research Center of Hierarchical Nanomaterials Shanghai Key Laboratory of Advanced Polymeric MaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Chemical Engineering Shanghai Engineering Research Center of Hierarchical NanomaterialsFrontiers Science Center for Materiobiology and Dynamic Chemistryand School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Aqueous zinc-ion capacitors (ZICs) are considered as potential candidates for next generation electrochemical energy storage devices due to their high safety and low ***,the existing aqueous ZICs usually have the problems of zinc dendrite growth and unsatisfactory performance at low ***,an erythritol (Eryt) additive with inhibition of zinc dendrites and anti-freezing capability was introduced into the *** experimental characterization and theoretical calculation confirm that the Eryt adsorbed on the surface of zinc anodes regulates the deposition orientation of Zn^(2+) and inhibits the formation of *** also reconstructs the solvation structure in the electrolyte to reduce water activity,enabling the electrolyte to have a lower freezing point for operation at low *** the assistance of Eryt,the Zn||Zn symmetric cell exhibits a long cycle life of 2000 h,while the ZIC assembled with activated carbon (AC) cathode and zinc anode (Zn||AC) maintains a capacity retention of 98.2% after 30,000 cycles at a current density of 10 A g^(-1)(even after 10,000 cycles at-20°C,the capacity retention rate reached 94.8%.).This work provides a highly scalable,low-cost and effective strategy for the protection of the anodes of low-temperature aqueous ZICs.

关键词： Zinc-ioncapacitors Electrolyte additive Dendrite-free Freeze-resistant electrolyte

Enhancing Evolutionary Algorithms With Pattern Mining for Sparse Large-Scale Multi-Objective Optimization Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1786-1801页

作者： Sheng Qi Rui wang Tao Zhang Weixiong Huang Fan Yu Ling wang College of Systems Engineering National University of Defense TechnologyChangsha 410073China College of Systems Engineering National University of Defense TechnologyChangsha 410073and also with the Xiangjiang LaboratoryChangsha 410205China College of Transportation and Engineering Central South UniversityChangsha 410073China Department of Automation Tsinghua UniversityBeijing 100084China

Sparse large-scale multi-objective optimization problems(SLMOPs)are common in science and ***,the large-scale problem represents the high dimensionality of the decision space,requiring algorithms to traverse vast expanse with limited computational ***,in the context of sparse,most variables in Pareto optimal solutions are zero,making it difficult for algorithms to identify non-zero variables *** paper is dedicated to addressing the challenges posed by *** start,we introduce innovative objective functions customized to mine maximum and minimum candidate *** substantial enhancement dramatically improves the efficacy of frequent pattern *** this way,selecting candidate sets is no longer based on the quantity of nonzero variables they contain but on a higher proportion of nonzero variables within specific ***,we unveil a novel approach to association rule mining,which delves into the intricate relationships between non-zero *** novel methodology aids in identifying sparse distributions that can potentially expedite reductions in the objective function *** extensively tested our algorithm across eight benchmark problems and four real-world *** results demonstrate that our approach achieves competitive solutions across various challenges.

关键词： Evolutionary algorithms pattern mining sparse large-scale multi-objective problems(SLMOPs) sparse large-scale optimization.

An electromagnetic semi-active dynamic vibration absorber for thin-walled workpiece vibration suppression in mirror milling

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1315-1334页

作者： Jianghua KONG Bei DING Wei wang Zhixia wang Juliang XIAO Hongyun QIU School of Mechanical Engineering Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin 300350China Key Laboratory of Modern Mechanisms and Equipment Design of the State Ministry of Education Tianjin UniversityTianjin 300350China

As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local *** address these challenges,we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA),which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror *** system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling ***,the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator,which alters the distance between *** resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool *** frequency shift characteristics and vibration absorption performance are comprehensively *** and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool,resulting in a vibration suppression rate of approximately 47.57%.Moreover,the roughness of the machined surface decreases by18.95%,significantly enhancing the surface *** results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process.

关键词： semi-active dynamic vibration absorber(SADVA) mirror milling selfsensing vibration absorption tuning thin-walled workpiece

Electrode design using revolving entity extraction for high-efficiency electric discharge machining of integral shrouded blisk

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Chinese Journal of Aeronautics 2021年第6期34卷 178-187页

作者： Yuchao JIA Guanxin CHI Yang SHEN Kun ZHANG Zhenlong wang Yukui wang School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Capital Aerospace Machinery Company China Academy of Launch Vehicle TechnologyBeijing 100076China

The integral shrouded blisk provides better performance with minimum weight,but its semi-open structure presents problems for its *** processes of these components require a removal of about 70%-90%of material from their ***-axis electrical discharge machining(EDM)is commonly used for these processes,but its poor efficiency cannot meet the requirements of mass *** flushing assisted high-current discharge is able to improve the machining *** this paper,this method was applied to manufacture the integral shrouded *** electrode design method was *** the largest revolving entity inside the flow channel as the base geometry,this laminated arc-shaped hollow electrode meets the requirements such as high pressure flushing,tool wear compensation,and easy to be made.A 4-axis linkage machining tool path with planetary motion was *** an integral guide vane ring as an example,it has been experimentally verified that the time consumption for each channel using this method was reduced to a half of the ordinary EDM method,while the finished surface quality remains same.

关键词： EDM Electrode High efficiency Trajectory Turbine blades

Fabrication of alginate-based microspheres with cellular structure for tuning ammonium dinitramide performance

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Defence Technology（防务技术） 2023年第10期28卷 111-120页

作者： Dun-ju wang Xu Zhou Yao-feng Mao Xin wang Ye-ming Huang Rui-hao wang Da-wei Zheng Co-Innovation Center for New Energetic Materials Southwest University of Science and TechnologyMianyang621010China China Academy of Engineering Physics Institute of Chemical MaterialsMianyang621900PR China

Recently,an emerging category green of energetic material ammonium dinitramide(ADN)has exhibited promising application in propellants due to its outstanding merits in energy release and environmental *** can be considered to substitute traditional oxidizer of ammonium perchlorate(AP)in military systems and *** this paper,a novel spherical energetic composite ADN/copper alginate(CA)with a microporous structure was designed and prepared by the W/O gel emulsion method,and a desirable porous microsphere structure was *** characterization techniques were used to investigate the structure and properties of ADN/CA *** results showed that ADN crystals were homogeneously encapsulated in an alginate-gel *** decomposition temperature was reduced to 151.7℃compared to ADN,while the activation energy of them was reduced from 129.73 k J/mol(ADN)to 107.50 k J/mol(ADN/CA-4).In addition,as-prepared samples had lower impact and frictional sensitivity than *** mechanism of sensitivity reduction and decomposition are also ***-volume combustion tests show that peak pressure of the ADN/CA-4 achieves 253.4 k Pa and pressurization rate of 2750.4 k Pa/***,this has a promising application in improving the combustion performance and safety performance of solid propellants.

关键词： Ammonium dinitramide Sodium alginate Microspheres High reactivity Energetic materials

Electrical control of excitonic oscillator strength and spatial distribution in a monolayer semiconductor

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Nano Research 2024年第9期17卷 8424-8430页

作者： Yanming wang Junrong Zhang Tianhua Ren Meng Xia Long Fang Xiangyi wang Xingwang Zhang Kai Zhang Junyong wang School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Nanophotonic Materials and Devices&Key Laboratory of Nanodevices and Applications i-LabSuzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of SciencesSuzhou 215123China Institute of Applied Physics and Materials Engineering University of MacaoTaipaMacao 999078China College of New Energy Inner Mongolia University of TechnologyHohhot 010051China

Electrical modulation of luminescence is significant to modern light-emitting *** transition metal dichalcogenides are emerging direct-bandgap luminescent materials with unique excitonic properties,and the multiple exciton complexes provide new opportunities to modulate the property of luminescence in atomically thin ***,we report an electrical control of exciton emission in the oscillator strength and spatial distribution of excitons in a monolayer *** modulation of excitonic emission intensity with a degree of modulation of~92%has been demonstrated by an electric field at room *** spatial carrier redistribution tuned by a lateral electric field results in distinct excitonic emission patterns by *** modulation approach to exciton oscillator strength and distribution provides an efficient way to investigate the exciton diffusion dynamics and to construct electrically tunable optoelectronic devices.

关键词： monolayer semiconductor exciton electrical modulation spatial distribution

Influence of welded pores on fatigue behavior of TC17 titanium alloy welded joints subjected to gigacycle regime at room and high temperatures

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Journal of Materials Science & Technology 2024年第11期178卷 1-21页

作者： Fulin Liu Yao Chen Lang Li Chong wang Qingyuan wang Yongjie Liu MOE Key Laboratory of Deep Earth Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan Province Sichuan UniversityChengdu 610207China Department of Mechanical Engineering Kyushu UniversityFukuoka 819-0395Japan

Welded structures in aero-engines commonly operate in high-temperature environments,making them susceptible to reduced fatigue life and premature failure due to welding defects within the ***,the gigacycle fatigue behaviors of titanium alloy welded joints at both room temperature(RT)and 400 ℃ were investigated,aiming to uncover the mechanism behind the formation of fine granular area(FGA)surrounding welded *** research findings demonstrate that the S-N curves of TC17 tita-nium alloy electron beam welded joint undergo a transition from a single linear decline at RT to a bilin-ear decline at 400 ℃.However,the fatigue failure mode remains unaffected by temperatures,and crack initiation is attributed to welded *** utilizing the Chapetti model curve to modify the Kitagawa-Takahashi(K-T)diagram,the lower threshold stress amplitude is introduced,enabling the determination of a safe size for welded pores at 400 ℃,which is calculated to be 11.3 μ***,the Gumbel probability distribution function is employed to assess the maximum size of welded ***,based on dislocation interactions,the formation mechanism of the FGA consisting of discontinuous nanograins with high-density dislocations is elucidated.

关键词： Titanium alloy Welded joints Gigacycle fatigue Welded pores High temperature Fine granular area

Peroxyacetyl nitrate measurements by thermal dissociation-chemical ionization mass spectrometry in an urban environment： performance and characterizations

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Frontiers of Environmental Science & Engineering 2017年第4期11卷 145-152页

作者： Xinfeng wang Tao wang Likun Xue Wei Nie Zheng Xu Steven C. N. Poon Wenxing wang Environment Research Institute Shandong University Jinan 250100 China Department of Civil and Environmental Engineering Hong Kong Polytechnic University Hong Kong 999077 China Institute for Climate and Global Change Research & School of Atmospheric Sciences Nanjing University Nanjing 210023 China

Peroxyacetyl nitrate （PAN） is an important indicator of photochemical smog and has adverse effects on human health and vegetation growth. A rapid and h!ghly selective technique of thermal dissociation chemical ionization mass spectrometry （TD-CIMS） was recently developed to measure the abundance of PAN in real time; however, it may be subject to artifact in the presence of nitric oxide （NO）. In this study, we tested the interference of the PAN signal induced by NO, evaluated the performance of TD- CIMS in an urban environment, and investigated the concentration and formation of PAN in urban Hong Kong. NO caused a significant underestimation of the PAN signal in TD-CIMS, with the underestimation increasing sharply with NO concentration and decreasing slightly with PAN abundance. A formula was derived to link the loss of PAN signal with the concentrations of NO and PAN, which can be used for data correction in PAN measurements. The corrected PAN data from TD- CIMS were consistent with those from the commonly used gas chromatography with electron capture detection, which confirms the utility of TD-CIMS in an urban environment in which NO is abundant. In autumn of 2010, the hourly average PAN mixing ratio varied from 0.06 ppbv to 5.17 ppbv, indicating the occurrence of photochemical pollution in urban Hong Kong. The tbrmation efficiency of PAN during pollution episodes was as high as 3.9 to 5.9 ppbv per 100 ppbv ozone. The efficiency showed a near-linear increase with NO, concentration, suggesting a control policy of NO,. reduction for PAN pollution.

关键词： TD-CIMS Peroxyacetyl nitrate Interference Photochemical pollution Formation efficiency