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Chinese Journal of Polymer Science 2024年第10期42卷 1610-1618,I0016页

作者： Xin-Yu Chen Yu-Bing Fu Xue-ling Yan Lan liu School of Materials Science and Engineering Key Lab of Guangdong Province for High Property and Functional Polymer MaterialsSouth China University of TechnologyGuangzhou510641China

Elastomers with high strength and toughness,excellent self-healing properties,and biocompatibility have broad application prospects in wearable electronics and other fields,but preparing it remains a *** this work,we propose a highly adaptable strategy by introducing the small molecule crosslinking agent of triethanolamine(TEA)to the poly(thioctic acid)(PTA)chains and preparing the PAx Ey elastomers using a simple synthesis *** strategy stabilizes the PTA chains by constructing multiple non-covalent cross-linked dynamic networks,endowing materials with excellent strength and toughness(tensile strength of 288 kPa,toughness of 278.2 kJ/m3),admirable self-healing properties(self-healing efficiency of 121.6%within 7 h at 70℃),and good *** PAx Ey elastomers can also be combined with MWNTs to become flexible strain sensors,which can be used to monitor human joint movements with high sensitivity,repeatable responses,and stability.

关键词： Thioctic acid Ion clusters Multiple dynamic networks Self-healing strengthening Flexible strain sensor

On the Polygonal Wear Evolution of Heavy-Haul Locomotive Wheels due to Wheel/Rail Flexibility and Its Mitigation Measures

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 40-61页

作者： Yunfan Yang Feifan Chai Pengfei liu Liang ling Kaiyun Wang Wanming Zhai State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway *** present,wheel/rail medium-or high-frequency frictional interactions are perceived as an essential reason of the high-order polygonal wear of railway wheels,which are potentially resulted by the flexible deformations of the train/track system or other external *** this work,the effect of wheel/rail flexibility on polygonal wear evolution of heavy-haul locomotive wheels is explored with aid of the long-term wheel polygonal wear evolution simulations,in which different flexible modeling of the heavy-haul wheel/rail coupled system is ***,the mitigation measures for the polygonal wear of heavy-haul locomotive wheels are *** results point out that the evolution of polygonal wear of heavy-haul locomotive wheels can be veritably simulated with consideration of the flexible effect of both wheelset and *** of mixed-line operation of heavy-haul trains and application of multicut wheel re-profiling can effectively reduce the development of wheel polygonal *** research can provide a deep-going understanding of polygonal wear evolution mechanism of heavy-haul locomotive wheels and its mitigation measures.

关键词： Heavy-haul locomotive Wheel polygonal wear Wheel/rail flexibility Long-term polygonal wear evolution Mitigation measures

Coaxial Wet Spinning of Boron Nitride Nanosheet‑Based Composite Fibers with Enhanced Thermal Conductivity and Mechanical Strength

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Nano-Micro Letters 2024年第2期16卷 126-138页

作者： Wenjiang Lu Qixuan Deng Minsu liu Baofu Ding Zhiyuan Xiong ling Qiu Tsinghua Shenzhen International Graduate School(TSIGS) Tsinghua UniversityShenzhen 518055People’s Republic of China Monash Suzhou Research Institute(MSRI) Monash UniversitySuzhou 215000People’s Republic of China Faculty of Materials Science and Engineering/Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Shenzhen Key Laboratory of Energy Materials for Carbon Neutrality Shenzhen 518055People’s Republic of China School of Light Industry and Engineering South China University of TechnologyGuangzhou 510614People’s Republic of China

Hexagonal boron nitride nanosheets(BNNSs)exhibit remarkable thermal and dielectric ***,their self-assembly and alignment in macroscopic forms remain challenging due to the chemical inertness of boron nitride,thereby limiting their performance in applications such as thermal *** this study,we present a coaxial wet spinning approach for the fabrication of BNNSs/polymer composite fibers with high nanosheet *** composite fibers were prepared using a superacid-based solvent system and showed a layered structure comprising an aramid core and an aramid/BNNSs ***,the coaxial fibers exhibited significantly higher BNNSs alignment compared to uniaxial aramid/BNNSs fibers,primarily due to the additional compressive forces exerted at the core-sheath interface during the hot drawing *** a BNNSs loading of 60 wt%,the resulting coaxial fibers showed exceptional properties,including an ultrahigh Herman orientation parameter of 0.81,thermal conductivity of 17.2 W m^(-1)K^(-1),and tensile strength of 192.5 *** results surpassed those of uniaxial fibers and previously reported BNNSs composite fibers,making them highly suitable for applications such as wearable thermal management *** findings present a promising strategy for fabricating high-performance composite fibers based on BNNSs.

关键词： Boron nitride nanosheets Coaxial fiber Interfacial compression Nanosheet aligning Wearable thermal management

Numerical and experimental investigation on hydraulic-electric rock fragmentation of heterogeneous granite

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International Journal of Mining Science and Technology 2024年第1期34卷 15-29页

作者： Xiaohua Zhu ling He Weiji liu Yunxu Luo Youjian Zhang Wuji Tang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China School of Mechanical Engineering Sichuan University of Science and EngineeringYibin 643002China

Hydraulic-electric rock fragmentation(HERF)plays a significant role in improving the efficiency of high voltage pulse rock ***,the underlying mechanism of HERF remains *** this study,considering the heterogeneity of the rock,microscopic thermodynamic properties,and shockwave time domain waveforms,based on the shockwave model,digital imaging technology and the discrete element method,the cyclic loading numerical simulations of HERF is achieved by coupling electrical,thermal,and solid mechanics under different formation temperatures,confining pressure,initial peak voltage,electrode bit diameter,and loading ***,the HERF discharge system is conducive to the laboratory experiments with various electrical parameters and the resulting broken pits are numerically reconstructed to obtain the geometric *** results show that,the completely broken area consists of powdery rock *** the pre-broken zone,the mineral cementation of the rock determines the transition of type CⅠcracks to type CⅡand type CⅢ***,the peak pressure of the shockwave increased with initial peak voltage but decreased with electrode bit diameter,while the wave front time ***,increasing well depth,formation temperature and confining pressure augment and inhibit HERF,but once confining pressure surpassed the threshold of 60 MPa for 152.40,215.90,and 228.60 mm electrode bits,and 40 MPa for 309.88 mm electrode bits,HERF is ***,for the same kind of rock,the volume and width of the broken pit increase with higher initial peak voltage and rock fissures will promote ***,the electrode drill bit with a 215.90 mm diameter is more suitable for drilling pink *** research contributes to a better microscopic understanding of HERF and provides valuable insights for electrode bit selection,as well as the optimization of circuit parameters for HERF technology.

关键词： Hydraulic-electric rock fragmentation Shockwave Thermodynamics Microcracks Weak Linear Parallel Bond Model

Waste acid recovery utilizing monovalent cation permselective membranes through selective electrodialysis

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Chinese Journal of Chemical Engineering 2024年第7期71卷 45-57页

作者： Yanran Zhu Yue Zhou Qian Chen Rongqiang Fu Zhaoming liu Liang ge Tongwen Xu Anhui Provincial Engineering Laboratory of Functional Membrane Materials and Technology Department of Applied ChemistrySchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Charged Polymeric Membrane Materials of Shandong Province Shandong Tianwei Membrane Technology Co.Ltd.Weifang 261000China

Selective electrodialysis(SED)has surfaced as a highly promising membrane separation technique in the realm of acid recovery owing to its ability to effectively separate monovalent ions through the utilization of a potential ***,the current SED process is limited by conventional commercial monovalent cation permselective membranes(MCPMs).This study systematically investigates the use of an independently developed MCPM in the SED process for acid *** factors such as current density,volume ratio,initial ion concentration,and waste acid systems are *** independently developed MCPM offers several advantages over the commercial monovalent selective cation-exchange membrane(CIMS),including higher recovered acid concentration,better ion flux ratio,improved acid recovery efficiency,increased recovered acid purity,and higher current *** SED process with the MCPM achieves a recovered acid of 95.9%and a concentration of 2.3 mol·L^(–1) in the HCl/FeCl_(2) system,when a current density of 20 mA·cm^(-2) and a volume ratio of 1:2 are ***,in the H_(2)SO_(4)/FeSO_(4) system,a purity of over 99%and a concentration of 2.1 mol·L^(–1) can be achieved in the recovered *** study thoroughly examines the impact of operation conditions on acid recovery performance in the SED *** independently developed MCPM demonstrates outstanding acid recovery performance,highlighting its potential for future commercial utilization.

关键词： Selective electrodialysis Wastewater Monovalent cation permselective membranes Separation Recovery

Controllability of Semilinear Integrodifferential Degenerate Sobolev Equations

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Journal of Systems Science & Complexity 2024年第5期37卷 1923-1936页

作者： ge Zhaoqiang School of Mathematics and Statistics Xi’an Jiaotong University

In this paper, the approximate controllability of semilinear integrodifferential degenerate Sobolev equations with nonlocal conditions is investigated in the sense of integral solution in Hilbert spaces. Some sufficient and necessary conditions are obtained. Firstly, the existence and uniqueness of integral solutions of semilinear integrodifferential degenerate Sobolev equations with nonlocal conditions are considered by ge-evolution operator theory and Sadovskii's fixed point theorem, the existence and uniqueness theorem of solutions is given. Secondly, the approximate controllability of semilinear integrodifferential degenerate Sobolev equations with nonlocal conditions is studied in the sense of integral solution. The criterion for approximate controllability is provided. The obtained results have important theoretical and practical value for the study of controllability of semilinear integrodifferential degenerate Sobolev equations with nonlocal conditions.

关键词： Approximate controllability ge-evolution operator integral solution Sadovskii’s fixed point theorem semilinear integrodifferential degenerate Sobolev equations

Visualization of MF/Diesel RCCI Combustion Process and Soot Emission

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Journal of Thermal Science 2024年第2期33卷 779-792页

作者： HUANG Chen NI Xiao ge Dameng LI Song ZHANG Wanzhi liu Jinping ZHANG Tingting School of Mechanical and Electronic Engineering Shandong Agricultural UniversityTaian271018China Shandong Provincial Engineering Laboratory of Agricultural Equipment Intelligence Taian271018China Taian Technician Institute Taian271000China Sinotruk Taian Wuyue Special Vehicle Co. Ltd.Taian271000China School of Mechanical Engineering Shaanxi University of TechnologyHanzhong723001China School of Mechanical Engineering Anyang Institute of TechnologyAnyang455000China

Based on the optical engine,the ignition characteristics,combustion process and soot emission characteristics of diesel under different 2-Methylfuran(MF) atmospheres were investigated by high-speed photography and in-cylinder combustion analysis *** results show that at the same main injection timing,the ignition time of reactivity controlled compression ignition(RCCI) combustion mode is earlier than pure diesel combustion,and the ignition point is concentrated near the *** acts as a spark plug to ignite the mixture,but the flame develops slowly in the early stages and the pressure in the cylinder rises *** with pure diesel,RCCI combustion model has smaller peak values of in-cylinder pressure and heat release rate,shorter ignition delay period,earlier combustion phase and shorter combustion *** main spray time at 6℃A BTDC and 12℃A BTDC,with the increase of MF premixing ratio from 0 to 0.75,the peak cylinder pressure decreased by 19.6% and 26% *** addition,with the increase of the MF heat value ratio,the area of KL factor> 1.5 in the combustion chamber decreased and the space integral natural luminescence(SINL) peak value decreased by 48.37%,and the soot formation rate and yield decreased ***,when the MF heat value ratio was too large(75% of the total calorific value),the ignition delay period increased,and misfire occurred at the main injection timing of 0℃A *** RCCI mode of MF/diesel dual fuel has better stability,and better control effect can be obtained at different main inj ection timing.

关键词： 2-methylfuran RCCI visualization two-color method KL factor

Potassium alleviated high nitrogen-induced apple growth inhibition by regulating photosynthetic nitrogen allocation and enhancing nitrogen utilization capacity

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Horticultural Plant Journal 2024年第1期10卷 1-14页

作者： Xinxiang Xu Guangyuan liu Jingquan liu Mengxue Lyu Fen Wang Yue Xing Hao Meng Min Li Yu Jiang ge Tian Zhanling Zhu Yuanmao Jiang Shunfeng ge State Key Laboratory of Crop Biology College of Horticulture Science and EngineeringShandong Agricultural UniversityTai'anShandong 271018China Key Laboratory of Biochemistry and Molecular Biology in Universities of Shandong College of Biological and Agricultural EngineeringWeifang UniversityWeifangShandong 261061China

There is a close relationship between potassium(K)and nitrogen(N).However,the roles of K under high N conditions remain *** a hydroponics approach,we monitored the morphological,physiological,and molecular changes in M9T337 apple(Malus domestica)rootstocks under different nitrate(10 and 30 mmol·L^(-1)NO_(3)^(-))and K supply(0.5,6,10,and 20 mmol·L_(-1)K^(+))*** revealed that high nitrate inhibited the root growth of M9T337 rootstocks,downregulated the expressions of K transporter genes(MdPT5,MdHKT1,and MdATK1),and reduced the net NO3-and K+influx at the surface of roots,thereby resulting in an N/K imbalance in *** investigation showed that 10 mmol·L^(-1)K increased the activity of N metabolic enzymes(NR,GS,NiR,and GOGAT),upregulated the expressions of genes related to nitrate uptake and transport(MdNRT1.1,MdNRT1.2,MdNRT1.5,and MdNRT2.4),promoted15N transport from the roots to the shoots,optimized leaf N distribution,and improved photosynthetic N utilization efficiency under high nitrate *** results suggest that the negative effects of high nitrate may be related to the N/K imbalance and that reducing N/K in plants by increasing K supply level can effectively alleviate the inhibition of N assimilation by high nitrate stress.

关键词： Apple rootstock K level High nitrate stress N metabolism ^(15)N

Study of interfacial transition zones between magnesium phosphate cement and Portland cement concrete pavement

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 523-537页

作者： Fei liu Baofeng Pan Changjun Zhou ge Li Xiaocun Wang Jiaquan Li Faculty of Infrastructure Engineering Dalian University of TechnologyDalian 116024China Tongren City Transportation Bureau Tongren 554300China Beijing Civil Aviation Design and Research Institute of China Design Group Beijing 101318China

The Portland cement concrete pavement(PCCP)often suffers from different environmental distresses and vehicle load failure,resulting in slab corner fractures,potholes,and other *** repair has become one of the effective ways to open traffic *** this study,a novel type of rapid repair material,basalt fiber reinforced polymer modified magnesium phosphate cement(BFPMPC),is used to rapidly repair ***,the mechanical properties and characteristics of the repair interfaces which are named interfacial transition zones(ITZs)formed by BFPMPC and cement concrete are focused on as a decisive factor for the performance of the rapid *** changing trend of the elastic moduli was studied by nanoindentation experiments in the ITZs with the deconvolution analysis that the elastic moduli of certain kinds of substances can be *** experimental results show that the elastic modulus of ITZ-1 with a width of about20μm can be regarded as 0.098 times of the aggregate,and 0.51 times of the ordinary Portland cement(OPC)*** BFPMPC-OPC mortar ITZ has roughly the same mechanical properties as the ITZ between aggregate and BFPMPC.A multi-scale representative two-dimensional model was established by random aggregate and a two-dimensional extended finite element method(XFEM)to study the mechanical properties of the repair *** simulation results show that the ITZ formed by the interface of BFPMPC and OPC mortar and basalt aggregate is the most vulnerable to failure,which is consistent with the nano-indentation experimental results.

关键词： Portland cement concrete pavement Interfacial transition zone Magnesium phosphate cement Repair interface Nanoindentation Mechanical properties and characteristics

Detoxification strategy of Microcystis aeruginosa to the toxicity of Cd(Ⅱ):role of EPS in alleviating toxicity

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Journal of Oceanology and Limnology 2024年第3期42卷 802-815页

作者： Xingye HAN Fangyuan liu Yibo ZHANG Kai CHENG Heyun WANG Hongmei ge Innovation Demonstration Base of Ecological Environment geotechnical and Ecological Restoration of Rivers and Lakes School of Civil EngineeringArchitecture and EnvironmentHubei University of TechnologyWuhan 430068China School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China National Engineering Research Center of Advanced Technology and Equipment for Water Environment Pollution Monitoring Wuhan 430068China

Although many studies have found that cadmium(Cd)can be toxic to microalgae,only a few reports focused on the role of extracellular polymeric substances(EPS)in Cd(Ⅱ)*** biochemical and physiological endpoints of Microcystis aeruginosa,including the composition and functional groups of soluble EPS(SL-EPS),loosely bound EPS(LB-EPS),and tightly bound EPS(TB-EPS),were detected to elucidate the toxicity and detoxification mechanisms of Cd(Ⅱ)for *** and physiological assays on *** showed that the 0.25-mg/L Cd(Ⅱ)resulted in a larger inhibition on growth and F_(v)/F_(m).Nevertheless,Cd(Ⅱ)significantly induced much higher contents of superoxide dismutase(SOD),intracellular microcystin LR(MC-LR),extracellular MC-LR,and *** electron microscopy with energy dispersive X-ray spectroscopy confirmed that Cd(Ⅱ)was absorbed into the EPS *** transform infrared spectrum analysis revealed that the functional groups bound with Cd(Ⅱ)of algae biomass,SL-EPS,LB-EPS,and TB-EPS were somewhat *** C=O/C=N groups ofδ-lactam or protein were their prominent functional groups,suggesting that amide or proteins in the EPS played a key role in the adsorption in Cd(Ⅱ).The concentration of 0.25 mg/L of Cd(Ⅱ)may change the chemical structure of EPS by altering the production of protein-like substances containing *** study indicated that *** could detoxify Cd(Ⅱ)stress via induction of antioxidant capacity(higher SOD activity and MC synthesis),EPS production,and modification in chemical structure of EPS.

关键词： Microcystis aeruginosa cadmium extracellular polymeric substances(EPS) microcystin detoxification