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Effect of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy

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Transactions of Nonferrous Metals Society of China 2024年第8期34卷 2415-2430页

作者： Xian-wen YANG Ling-ying ye Yong ZHANG Quan-shi CHENG School of Materials Science and Engineering Central South UniversityChangsha 410083China Aerospace Precision Production Co. Ltd.Tianjin 300300China

The effects of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy extruded bar were investigated through various analyses,including electrical conductivity,mechanical properties,local corrosion properties,and slow strain rate tensile stress corrosion *** characterization techniques such as metallographic microscopy,scanning electron microscopy(SEM),and transmission electron microscopy(TEM)were also *** results indicate that the tensile strength of the alloy produced by T6I6 aging is similar to that produced by T6I4 aging,and it even exceeds 700 ***,the yield strength increases by 52.7 MPa,reaching 654.8 MPa after T6I6 aging *** maximum depths of intergranular corrosion(IGC)and exfoliation corrosion(EXCO)decrease from 116.3 and 468.5μm to 89.5 and 32..3μm,*** stress corrosion factor also decreases from 2.1%to 1.6%.These findings suggest that the alloy treated with T6I6 aging exhibits both high strength and excellent stress corrosion cracking ***,when the alloy is treated with T6I4,T6I6 and T6I7 aging,the sizes of grain boundary precipitates(GBPs)are found to be 5.2.18.4,and 32.8 nm,*** sizes of matrix precipitates are 4.8,5.7 and 15.7 nm,*** atomic fractions of Zn in GBPs are 9.92.at.%,8.2. at.%and 6.87 at.%,respectively,while the atomic fractions of Mg are 12.66 at.%,8.43 at.%and 7.00 at.%,***,the atomic fractions of Cu are 1.83 at.%,2.47 at.%and 3.41 at.%,respectively.

关键词： 7A75 aluminum alloy interrupted aging aging precipitation behavior mechanical properties intergranular corrosion exfoliation corrosion stress corrosion cracking

Design and experimental research on the sweet potato seedling transplanting mechanism of the planetary gear train with deformed elliptical gear transmission

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 91-99页

作者： Bingliang ye Yuxuan ye Haili Zhou Gaohong Yu Xiong Zhao Bin Deng Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Zhejiang Province Key Laboratory of Transplanting Equipment and Technology Hangzhou 310018China Key Laboratory of Agricultural Equipment for Hilly and Mountainous Areas in Southeastern China(Co-construction by Ministry and Province) Ministry of Agriculture and Rural AffairsHangzhou 310018China

Aiming at the lack of suitable machines for sweet potato seedling transplanting in China,and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling,a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical *** working principle of the transplanting mechanism was analyzed,and the kinematics modeling and analysis of the mechanism were carried *** study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting *** parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting *** on the optimized parameters,the structure of the transplanting mechanism was designed,and a virtual prototype of the mechanism was created,whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the *** high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism’s kinematic characteristics and transplanting *** test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory,meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling;And when the rotary speed of the mechanism are 2. r/min and 30 r/min,the average success ratios of sweet potato seedlings transplanting are 90%and 82.,respectively,which prove the application feasibility of the mechanism in the practical machines.

关键词： sweet potato seedling transplanter transplanting mechanism deformed elliptical gear transmission kinematics analysis membership function optimization design

One-pot synthesis of N-doped petroleum coke-based microporous carbon for high-performance CO_(2. adsorption and supercapacitors

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Journal of Environmental Sciences 2024年第5期139卷 93-104页

作者： wenfu Zhu Yuqin Wang Fan Yao Xiaohong Wang Haoming Zheng Guangzheng ye Hairong Cheng Junliang Wu Haomin Huang Daiqi ye School of Environment and Energy South China University of TechnologyGuangzhou 510006China National Engineering Laboratory for VOCs Pollution Control Technology and Equipment Guangzhou 510006China Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control(SCUT) Guangzhou 510006China Guangdong Provincial Engineering and Technology Research Centre for Environmental Risk Prevention and Emergency Disposal South China University of TechnologyGuangzhou 510006China

Waste resource utilization of petroleum coke is crucial for achieving global carbon emission ***,a series of N-doped microporous carbons were fabricated from petroleum coke using a one-pot synthesis *** as-prepared samples had a large specific surface area(up to 2.12.m^(2./g),a moderate-high N content(up to 4.82.at.%),and high population(55%)of ultra-micropores(2.adsorption and *** ambient pressure,the optimal N-doped petroleum coke-based microporous carbon exhibited the highest CO_(2.uptake of 4.2. mmol/g at 2.℃ and 6.57 mmol/g at 0℃.These values are comparable or even better than those of numerous previously reported adsorbents prepared by multistep synthesis,primarily due to the existence of *** sample exhibited excellent CO_(2./N_(2.selectivity at 2.℃ owing to the abundant basic pyridinic and pyrrolic N species;and showed superior CO_(2.adsorption-desorption cycling performance,which was maintained at 97% after 10 cycles at 2.℃.Moreover,petroleum coke-based microporous carbon,with a considerably high specific surface area and hierarchical pore structure,exhibited excellent electrochemical performance over the N-doped sample,maintaining a favorable specific capacitance of 2.3.2.F/g at 0.5 A/g in 6 mol/L KOH aqueous *** study provides insight into the influence of N-doping on the porous properties of petroleum coke-based ***,the as-prepared carbons were found to be promising adsorbents for CO_(2.adsorption,CO_(2./N_(2.separation and electrochemical application.

关键词： One-pot synthesis N-doped microporous carbon CO_(2.adsorption CO_(2./N_(2.selectivity Electrochemical performance

Current Mycoplasma pneumoniae epidemic among children in Shanghai:unusual pneumonia caused by usual pathogen

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World Journal of Pediatrics 2024年第1期20卷 5-10页

作者： Xiao-Bo Zhang wen He Yong-Hao Gui Quan Lu Yong Yin Jian-Hua Zhang Xiao-Yan Dong Ying-wen Wang Ying-Zi {2. Hong Xu Jia-Yu Wang Bing Shen Dan-Ping Gu Li-Bo Wang Yi Wang Department of Respiratory Medicine Children's Hospital of Fudan University399 Wanyuan RoadShanghai 201102China State Key Laboratory of Genetic Engineering at School of Life Sciences Institute of Reproduction&DevelopmentChildren's Hospital of Fudan UniversityShanghaiChina Department of Respiratory Medicine Children's Hospital of Shanghai Jiao Tong UniversityShanghaiChina Department of Respiratory Medicine Shanghai Children's Medical CenterAffiliated to Shanghai Jiaotong University School of MedicineShanghaiChina Department of Pediatric Respiratory Xinhua HospitalAffiliated to Shanghai Jiaotong University School of MedicineShanghaiChina Department of Nursing Children's Hospital of Fudan UniversityShanghaiChina Department of Infectious Diseases Children's Hospital of Fudan UniversityShanghaiChina Department of Nephrology Children's Hospital of Fudan UniversityShanghaiChina NHC Key Laboratory of Neonatal Diseases Children's Hospital of Fudan UniversityShanghaiChina Shanghai Shenkang Hospital Development Center ShanghaiChina Center for Medical Quality Control Management of Shanghai ShanghaiChina Department of Neurology Children's Hospital of Fudan University399Wanyuan RoadShanghai 201102China

Mycoplasma pneumoniae(***),primarily transmitted through respiratory droplets when infected individuals cough or sneeze,is a common cause of communityacquired pneumonia,especially among school-age children and *** infection occurs endemically with an epidemic peak every few *** worldwide incidence confirmed by direct test methods was reported to be 8.61%between 2.17 and 2.2. across all age groups[1].

关键词： pneumonia epidemic respiratory

Structural phase transition in a new organic-inorganic hybrid post-perovskite:(N,N-dimethylpyrrolidinium)[Mn(N(CN)_(2.)_(3)]

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Chinese Journal of Structural Chemistry 2024年第6期43卷 40-44页

作者： Le ye Wei-Xiong Zhang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistryIGCMESun Yat-Sen UniversityGuangzhou510275China

In the realm of molecular phase transition research,particularly for applications in sensors,data storage and switching technologies,the role of organic-inorganic hybrid perovskite materials has been increasingly recognized for their significant ***,hybrid post-perovskites,as a critical subclass of perovskites,have not been thoroughly studied and mainly limit in the instances based on polyatomic bridging agents like dicyanamide(dca^(-))and non-cyclic organic ***,a polar cyclic quaternary ammonium cation,N,N-dimethylpyrrolidinium(DMP^(+)),was used to assemble a new hybrid post-perovskite,(DMP)[Mn(dca)_(3)](1),which undergoes a phase transition from orthorhombic Bmmb to monoclinic P2.(1)/n space group at 2.9 *** employing multiple techniques such as differential scanning calorimetry,variable-temperature single-crystal X-ray analysis,dielectric measurements,and Hirshfeld surface analysis,we disclosed the role of polar cyclic quaternary ammonium DMP^(+)in elevating the phase-transition temperature by 48 K,generating significant dielectric switching effect and facilitating interlayer sliding of inorganic framework.

关键词： Structural phase transitions Dielectric switching Organic-inorganic hybrid crystals Post-perovskites

Joint deletion of multifunctional MGF505-7R and H2.0R genes generates a safe and effective African swine fever virus attenuated live vaccine candidate

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Virologica Sinica 2024年第3期39卷 355-357页

作者： Changjiang weng Li Huang Guangqiang ye Division of Fundamental Immunology National African Swine Fever Para-reference LaboratoryState Key Laboratory for Animal Disease Control and PreventionHarbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069China Heilongjiang Provincial Key Laboratory of Veterinary Immunology Harbin 150069China

African swine fever(ASF)caused by the ASF virus(ASFV)is a highly contagious disease of pigs and wild ***,there are no safe,effective commercial vaccines *** genome of ASFV HLJ/18 contains more than 180 genes,including a few virulence-related *** these key virulence genes through individual deletion and subsequent pathogenicity testing in pigs is a laborious *** addition,some ASFV genes are indispensable for viral replication and cannot be *** the past 30 years,scientists have confirmed that certain ASFV genes particularly those host antiviral innate immune responses,are associated with the virulence of ASFV *** knockout of these genes does not impact viral replication,it does attenuate the virulence of ASFV in *** immunized with these live attenuated vaccine candidates can provide partial or complete *** on these findings,we propose a new concept that ASFV immunomodulatory genes involved in type I interferon(IFN)production,IFN-JAK-STAT signaling,inflammatory responses,cell death(involved in apoptosis,necrosis,and pyroptosis),and autophagy may be related to the pathogenicity of *** unbiased screening may identify more ASFV immunomodulatory or multifunctional genes,simplifying the confirmation of ASFV virulence-related *** line with these theories,we have identified MGF505-7R and H2.0R as key virulence genes determining the pathogenicity of the ASFV HLJ/18 *** of MGF505-7R,H2.0R alone or both attenuate the virulence of ASFV HLJ/18 in pigs,providing a paradigm for developing attenuated live vaccines from basic research results.

关键词： attenuated fever swine

Catalytic effect in lithium metal batteries: From heterogeneous catalyst to homogenous catalyst

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Journal of Energy Chemistry 2024年第3期90卷 305-326,I0008页

作者： Haining Fan Xuan-wen Gao Hailong Xu Yichun Ding Shi-Xue Dou wen-Bin Luo School of Fashion and Textiles The Hong Kong Polytechnic UniversityHong Kong 100872China Institute for Energy Electrochemistry and Urban Mines Metallurgy School of MetallurgyNortheastern UniversityShenyang 110819LiaoningChina Institute of Energy Materials Science University of Shanghai for Science and TechnologyShanghai 200000China State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710000ShaanxiChina

Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical *** the broader implementation,the primary obstacle lies in the intricate multi-electron,multi-step redox reaction associated with sluggish conversion kinetics,subsequently giving rise to a cascade of parasitic *** order to smooth reaction kinetics,catalysts are widely introduced to accelerate reaction rate via modulating the energy *** past decades,a large amount of research has been devoted to the catalyst design and catalytic mechanism exploration,and thus the great progress in electrochemical performance has been ***,it is necessary to make a comprehensive review toward key progress in catalyst design and future development *** this review,the basic mechanism of lithium metal batteries is provided along with corresponding advantages and existing challenges detailly *** main catalysts employed to accelerate cathode reaction with emphasis on their catalytic mechanism are summarized as ***,the rational design and innovative direction toward efficient catalysts are suggested for future application in metal-sulfur/gas battery and *** review is expected to drive and benefit future research on rational catalyst design with multi-parameter synergistic impacts on the activity and stability of next-generation metal battery,thus opening new avenue for sustainable solution to climate change,energy and environmental issues,and the potential industrial economy.

关键词： Energy storage and conversion Metal battery Sulfur battery Air battery Catalytic effect Heterogeneous catalyst Homogeneous catalyst

Black hole evaporation and its remnants with the generalized uncertainty principle including a linear term

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Communications in Theoretical Physics 2024年第2期76卷 125-136页

作者： Bo Yu Zheng-wen Long College of Physics Guizhou UniversityGuiyang550025China

In recent years,researchers have investigated the evaporation of Schwarzschild black holes using various forms of the generalized uncertainty principle(GUP),metric quantum correction,and noncommutative geometry,***,there are differences between the GUP correction and the other two methods in terms of describing the later stages of black hole ***,some studies argue that the GUP with a negative parameter cannot effectively correct black hole evaporation,while others contend that the positivity or negativity of the GUP parameters should not affect the correction *** the above into consideration,we reconsider black hole evaporation with the generalized uncertainty principle including a linear term(LGUP),and examine the case of negative *** results indicate that the evaporation behavior of both Schwarzschild black holes and Reissner–Nordstr?m black holes,under LGUP correction,is consistent with the results of metric quantum correction and non-commutative ***,the negative parameter LGUP can also effectively correct for black hole evaporation.

关键词： black hole evaporation generalized uncertainty principle negative parameter

Enhancing MXene-based supercapacitors:Role of synthesis and 3D architectures

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Journal of Energy Chemistry 2024年第4期91卷 1-26页

作者： wen Siong Poh wen Jie Yiang Wee-Jun Ong Pau Loke Show Chuan Yi Foo School of Energy and Chemical Engineering Xiamen University MalaysiaSelangor Darul EhsanMalaysia&College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina Kelip-kelip!Center of Excellence for Light Enabling Technologies Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Center of Excellence for NaNo Energy&Catalysis Technology(CONNECT) Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Department of Chemical Engineering Khalifa UniversityShakhbout Bin Sultan St-Zone 1Abu DhabiUnited Arab Emirates Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection Wenzhou UniversityWenzhou 325035ZhejiangChina Department of Chemical and Environmental Engineering Faculty of Science and EngineeringUniversity of Nottingham MalaysiaJalan Broga43500 SemenyihSelangor Darul EhsanMalaysia Department of Sustainable Engineering Saveetha School of EngineeringSIMATSChennai 602105India

MXene has been the limelight for studies on electrode active materials,aiming at developing supercapacitors with boosted energy density to meet the emerging influx of wearable and portable electronic *** its various desirable properties including intrinsic flexibility,high specific surface area,excellent metallic conductivity and unique abundance of surface functionalities,its full potential for electrochemical performance is hindered by the notorious restacking phenomenon of MXene *** to its two-dimensional(2.)nature and surface functional groups,inevitable Van der Waals interactions drive the agglomeration of nanosheets,ultimately reducing the exposure of electrochemically active sites to the electrolyte,as well as severely lengthening electrolyte ion transport *** a result,energy and power density deteriorate,limiting the application versatility of MXene-based *** 3D architectures using 2. nanosheets presents as a straightforward yet ingenious approach to mitigate the fatal flaws of ***,the sheer number of distinct methodologies reported,thus far,calls for a systematic review that unravels the rationale behind such 3D MXene structural ***,this review aims to serve this purpose while also scrutinizing the structure–property relationship to correlate such structural modifications to their ensuing electrochemical performance ***,the physicochemical properties of MXene play fundamental roles in determining the effective charge storage capabilities of 3D MXene-based *** largely depends on different MXene synthesis techniques and synthesis condition variations,hence,elucidated in this review as ***,the challenges and perspectives for achieving viable commercialization of MXene-based supercapacitor electrodes are highlighted.

关键词： MXene 3D architectures Synthesis design Supercapacitor Energy storage