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Chinese Journal of Polymer Science 2024年第7期42卷 916-925,I0006页

作者： Bin Zhang Zheng-Li dou Yong-Zheng Zhang Qiang Fu Kai Wu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

Effective thermal transport across solid-solid interfaces which is essential in thermal interface materials(TIMs),necessitates both optimal thixotropy and high thermal *** role of filler surface modification,a fundamental aspect of TIM fabrication,in the influence of these properties is not fully *** study employs the use of a silane coupling agent(SCA)to modify alumina,integrating experimental approaches with molecular dynamics simulations,to elucidate the interface effects on thixotropy and thermal conductivity in polydimethylsiloxane(PDMS)-based *** findings reveal that the variations of SCAs modify both interface binding energy and transition layer *** interface binding energy restricts macromolecular segmental relaxation near the interface,hindering desirable thixotropy and bond line *** the contrary,the thickness of the transition layer at the interface positively influences thermal conductivity,facilitating the transport of phonons between the polymer and ***,selecting an optimal SCA allows a balance between traditionally conflicting goals of high thermal conductivity and minimal bond line thickness,achieving an impressively low interface thermal resistance of just 2.45-4.29 K·mm^(2)·W^(-1)at275.8 kPa.

关键词： Thermal interface material Surface modification Thermal conductivity Thixotropy Interface thermal resistance

Nano-sized stationary phase packings retained by single-particle frit for microchip liquid chromatography

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Chinese Chemical Letters 2024年第4期35卷 486-489页

作者： Wangyan Hu Ke Li Xiangnan dou Ning Li Xiayan Wang Center Excellence for Environmental Safety and Biological Effects Beijing Key Laboratory for Green Catalysis and SeparationDepartment of ChemistryBeijing University of TechnologyBeijing 100124China Center for Environmental Metrology National Institute of MetrologyBeijing 100029China

Modern chromatography is increasingly focused on miniaturization and integration. Compared to conventional liquid chromatography, microfluidic chip liquid chromatography(microchip-LC) has the potential due to its zero-dead volume connection and ease of integration. Nano-sized packings have the potential to significantly enhance separation performance in microchip-LC. However, their application has been hindered by packing difficulties. This study presents a method for packing nano-sized silica particles into a microchannel as the stationary phase. The microchip-LC packed column was prepared by combining the weir and the porous silica single-particle as frit to retain the packing particles. A surface tensionbased single-particle picking technique was established to insert porous single-particle frit into glass microchannels. Additionally, we developed a slurry packing method that utilizes air pressure to inject nano-sized packing into the microchannel. Pressure-driven chromatographic separation was performed using this nano-packed column integrated into a glass microchip. The mixture of four PAHs was successfully separated within just 8 min using a 5 mm separation channel length, achieving high theoretical plates(10~6plates/m). Overall, these findings demonstrate the potential of utilizing nano-sized packings for enhancing chromatographic performance in microchip systems.

关键词： Nano-size packing Single-particle frit Packed column Microchip LC Chromatographic separation

Large Deviations for a Critical Galton-Watson Branching Process

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Acta Mathematicae Applicatae Sinica 2024年

作者： dou-dou LI Wan-lin SHI Mei ZHANG College of Statistics and Data Science Faculty of Science Beijing University of Technology Laboratory of Mathematics and Complex Systems (Ministry of Education) School of Mathematical SciencesBeijing Normal University Department of Mathematics and Physics North China Electric Power University

In this paper, a critical Galton-Watson branching process{Zn}is considered. Large deviation rates of SZn:=∑i=1ZnXiare obtained, where{Xi, i≥1}is a sequence of independent and identically distributed random variables and X1is in the domain of attraction of an α-stable law with α∈(0, 2). One shall see that the convergence rate is determined by the tail index of X1and the variance of Z1. Our results can be compared with those ones of the supercritical case.

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Dual-filler reinforced PVDF-HFP based polymer electrolyte enabling high-safety design of lithium metal batteries

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Nano Research 2024年第6期17卷 5251-5260页

作者： Chang Fang Kangsheng Huang Jing Zhao Shiqi Tian Hui dou Xiaogang Zhang Jiangsu Key Laboratory of Electrochemical Energy Storage Technologies College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China

Despite the high energy density of lithium metal batteries(LMBs),their application in rechargeable batteries is still hampered due to insufficient ***,we present a novel flame-retardant solid-state electrolyte based on polyvinylidene fluoride-hexafluoropropylene(PVDF-HFP)with nano SiO_(2)aerogel as an inert filler but Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)as an auxiliary component to enhance the ion *** introduction of SiO_(2)aerogels imparts the polymer electrolyte with exceptional thermal stability and flame ***,the interaction between hydroxyl groups of SiO_(2)particles and PVDF-HFP creates a strong cross-linking structure,enhancing the mechanical strength and stability of the ***,the presence of SiO_(2)aerogel and LLZTO facilitates the dissociation of lithium salts through Lewis acid-base interactions,resulting in a high ionic conductivity of 1.01×10^(−3)S·cm^(−1)and a wide electrochemical window of~5.0 V at room temperature for the prepared ***,the assembled Li|Li cell demonstrates the excellent resistance to lithium dendrite and runs stablly for over 1500 h at a current density of 0.25 mA·cm^(−2).Thus,we prepare a pouch cell with high safety,which can work normally after short-circuiting under the external folding and cutting.

关键词： polymer electrolyte SiO_(2)/Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)dual-filler non-flammable long cycle life lithium metal battery

Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient oxidative self-coupling of benzylamines

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 95-106页

作者： Jie Chen Mingyuan Jian Deqiong Xie Kecan dou Deli Chen Weidong Zhu Fumin Zhang Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China

In this study,we synthesize a catalyst comprising cobalt nanoparticles supported on MXene by pyrolyzing a composite in a N2 ***,the composite comprises a bimetallic Zn/Co zeolitic imidazole framework grown in situ on the outer surface of *** catalytic efficiency of the catalyst is tested for the self-coupling of 4-methoxybenzylamine to produce value-added imine,where atmospheric oxygen(1 atm)is used as the *** on the results,the catalyst displayed impressive catalytic activity,achieving 95.4%yield of the desired imine at 383 K for 8 ***,the catalyst showed recyclability and tolerance toward benzylamine substrates with various functional *** outstanding performance of the catalyst is primarily attributed to the synergetic catalytic effect between the cobalt nanoparticles and MXene support,while also benefiting from the three-dimensional porous ***,a preliminary investigation of potential reaction mechanisms is conducted.

关键词： MXene sacrificial template oxidative self-coupling Co nanoparticles imine

Effect of slag composition on kinetic behavior of deep deoxidation of 5 wt.% Si high-silicon austenitic stainless steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1873-1885页

作者： Guan-xiong dou Han-jie Guo Jing Guo Xue-cheng Peng Qing-yun Chen School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing 100083China

Based on a thermodynamic study of 5 wt.%Si high-silicon austenitic stainless steel(SS-5Si)smelting using CaF_(2)-CaO-Al_(2)0_(3)-Mg-Si0_(2) slag to obtain a low oxygen content of less than 10×10^(-4) wt.%,a kinetic mass transfer model for deep deoxidation was established through laboratory studies,and the effects of slag components and temperature on deoxidation during the slag-steel reaction process of sS-5Si were systematically *** experimental data verified the accuracy of the model *** results showed that the final oxygen content in the steel at 1873 K was mainly controlled by the oxygen content derived from the activity of SiO_(2) regulated by the[Si]-[O]equilibrium reaction in the slag system;in particular,when the slag basicity R(R=w(CaO)/w(SiO2),where w(CaO)and w(SiO_(2))are the contents of CaO and SiO_(2) in the slag,respectively)is 3,the Al2O3 content in the slag needs to be less than 2.7%.The mass transfer rate equation for the kinetics of the deoxidation reaction revealed that the mass transfer of oxygen in the liquid metal is the rate-controlling step under different slag conditions at 1873 K,and the oxygen transfer coefficient ko.m increases with increasing the slag basicity from 4.0×10^(-6)m s^(-1)(R=1)to 4.3×10^(-5) m s^(-1)(R=3).ko.m values at R=2 and R=3 are almost the same,indicating that high slag basicity has little *** integral of the mass transfer rate equation for the deoxidation reaction of SS-5Si under different slag conditions is *** total oxygen content of the molten steel decreases with increasing basicity from an initial content of 22×10^(-4) to 3.2×10^(-4) wt.%(R=3),consistent with the change in ko.m with slag *** R=2,the slag-steel reaction takes 15 min to reach equilibrium(w[O]=5.5×10^(-4) wt.%),whereas at R=3,the slag-steel reaction takes 30 min to reach equilibrium(w[0]=3.2×10^(-4) wt.%).Considering the depth of deoxidation and reaction time of SS-5Si smelting,it is recommended the slag b

关键词： Slag-steel reaction Kinetics Rate-controlling step Deep deoxidation Transfer coefficient

Nano friction behaviour between magnetic materials and copper considering the inter-diffusion effect

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Friction 2024年第7期12卷 1532-1547页

作者： Zilin LI Lisha dou Shiyu YANG Huajiang OUYANG Qichen ZHU Xiaoyang CHEN Xin JIA Shuaiwei dou Xiaolong CUI Yudong ZHANG Jingjiang QIU Guochen QI Bangbang NIE Pan LIU Ronghan WEI School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhou 450001China Engineering Technology Research Center of Henan Province for MEMS Manufacturing and Application Zhengzhou UniversityZhengzhou 450001China Institute of Intelligent Sensing Zhengzhou UniversityZhengzhou 450001China School of Engineering University of LiverpoolLiverpool L693GHUK School of Cyber Science and Engineering&Hanwei Institute of Internet of Things Zhengzhou UniversityZhengzhou 450001China

Copper,permalloy,cobalt,and silicon are the materials that have been widely utilised in magnetic *** the size of interest is down to the nanoscale,the inter-diffusion between certain materials becomes *** paper studies the nanoscale friction characteristics between frictional pairs with and without inter-diffusion properties through the atomic force *** distinct evolution features of nanoscale friction force when inter-diffusion is involved are discovered experimentally,which is also confirmed through theoretical ***,through the thin film deposition method,four pairs of contact materials(Cu–Ni_(81)Fe_(19),Si–Ni_(81)Fe_(19),Cu–Co,Cu–Si)are designed for friction tests,in which diffusion occurs at the interface of Cu–Ni_(81)Fe_(19)***,the effects of sliding velocity and loading force on the nano friction of each pair are *** is found that regardless of the diffusion phenomenon:(1)the adhesion force values exhibit a notable correlation to the values of the friction force;(2)the friction force in all four material pairs consistently increases with the growth of the normal loading force,although the growth rate may *** terms of the sliding velocity effect,the friction forces of immiscible materials(Si–Ni_(81)Fe_(19),Cu–Co,and Cu–Si)are found to increase with the increasing sliding ***,the friction force of Cu–Ni_(81)Fe_(19),decreases with the increasing sliding ***,a compositive friction model considering both the velocity and the normal force effect was proposed,which shows good agreement with the experimental results and explains the nano friction behaviour of both miscible and immiscible metals.

关键词： atomic force microscope friction force normal load sliding velocity

Blade-Coated Porous 3D Carbon Composite Electrodes Coupled with Multiscale Interfaces for Highly Sensitive All-Paper Pressure Sensors

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Nano-Micro Letters 2024年第12期16卷 217-232页

作者： Bowen Zheng Ruisheng Guo Xiaoqiang dou Yueqing Fu Bingjun Yang Xuqing Liu Feng Zhou State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China Research Center of Resource Chemistry and Energy Materials State Key Laboratory of Solid LubricationLanzhou Institute of Chemical PhysicsChinese of Academy of SciencesLanzhou 730000People’s Republic of China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000People’s Republic of China Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai 264006People’s Republic of China

Flexible and wearable pressure sensors hold immense promise for health monitoring,covering disease detection and postoperative *** pressure sensors with high sensitivity,wide detection range,and cost-effectiveness is *** leveraging paper for its sustainability,biocompatibility,and inherent porous structure,herein,a solution-processed all-paper resistive pressure sensor is designed with outstanding performance.A ternary composite paste,comprising a compressible 3D carbon skeleton,conductive polymer poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate),and cohesive carbon nanotubes,is blade-coated on paper and naturally dried to form the porous composite electrode with hierachical micro-and nano-structured *** with screen-printed Cu electrodes in submillimeter finger widths on rough paper,this creates a multiscale hierarchical contact interface between electrodes,significantly enhancing sensitivity(1014 kPa-1)and expanding the detection range(up to 300 kPa)of as-resulted all-paper pressure sensor with low detection limit and power *** versatility ranges from subtle wrist pulses,robust finger taps,to large-area spatial force detection,highlighting its intricate submillimetermicrometer-nanometer hierarchical interface and nanometer porosity in the composite ***,this all-paper resistive pressure sensor,with its superior sensing capabilities,large-scale fabrication potential,and cost-effectiveness,paves the way for next-generation wearable electronics,ushering in an era of advanced,sustainable technological solutions.

关键词： Micro-and nano-structures PEDOT:PSS Flexible pressure sensors Health monitoring Multiscale interfaces

Predicted Climate Change will Increase Landslide Risk in Hanjiang River Basin,China

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Journal of Earth Science 2024年第4期35卷 1334-1354页

作者： Xinggang Tang Lingjian Wang Huiyong Wang Yingdan Yuan dou Huang Jinchi Zhang Co-Innovation Center for Sustainable Forestry in Southern China Jiangsu Province Key Laboratory of Soil and Water Conservation and Ecological RestorationNanjing Forestry UniversityNanjing210037China Jiangsu Key Laboratory of Crop Genetics and Physiology College of Horticulture and Plant ProtectionYangzhou UniversityYangzhou225009China College of Forestry Nanjing Forestry UniversityNanjing210037China

Landslides are widespread geomorphological phenomena with complex mechanisms that have caused extensive causalities and property damage *** scale and frequency of landslides are presently increasing owing to the warming effects of climate change,which further increases the associated safety *** this study,the relationship between historical landslides and environmental variables in the Hanjiang River Basin was determined and an optimized model was used to constrain the relative contribution of variables and best spatial response *** optimal MaxEnt model was used to predict the current distribution of landslides and influence of future rainfall changes on the landslide *** results indicate that environmental variables in the study area statistically correlate with landslide events over the past 20 *** MaxEnt model evaluation was applied to landslide hazards in the Hanjiang River Basin based on current climate change *** results indicate that 25.9%of the study area is classified as a high-risk *** main environmental variables that affect the distribution of landslides include altitude,slope,normalized difference vegetation index,annual precipitation,distance from rivers,and distance from roads,with a cumulative contribution rate of approximately 90%.The annual rainfall in the Hanjiang River Basin will continue to increase under future climate warming *** rainfall will further increase the extent of high-and medium-risk areas in the basin,especially when following the RCP8.5 climate prediction,which is expected to increase the high-risk area by 10.7%by ***,high landslide risk areas in the basin will migrate to high-altitude areas in the future,which poses new challenges for the prevention and control of landslide *** study demonstrates the usefulness of the MaxEnt model as a tool for landslide susceptibility prediction in the Hanjiang River Basin caused by global warming and yi

关键词： Hanjiang River Basin climate change environmental factor landslide susceptibility assessment MaxEnt model

Aluminum exposure impairs oocyte quality via subcellular structure disruption and DNA damage-related apoptosis in mice

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Journal of Environmental Sciences 2024年第5期139卷 308-319页

作者： Hongge Li Jingcai Liu Weihua Nong Mengying Shen Sheng dou Shaochen Sun Junli Wang The Affiliated Hospital of Youjiang Medical University for Nationalities Guangxi 533000China College of Animal Science and Technology Nanjing Agricultural UniversityNanjing 210095China School of Medical Laboratory Youjiang Medical University for NationalitiesGuangxi 533000China Industrial College of Biomedicine and Health Industry Youjiang Medical University for NationalitiesGuangxi 533000China Reproductive Medicine Guangxi Medical and Health Key Discipline Construction ProjectThe Affiliated Hospital of Youjiang Medical University for NationalitiesGuangxi 533000China

Aluminum(Al)can lead to an exposure of creature in varieties ways for its universality,and it could disturb normal physiological metabolism,with the damage to multisystem including *** the oocyte quality is critical for female reproduction,we inspected the toxicity of Al on mouse oocyte *** constructed in vitro exposure mouse model,and we found that 5 mmol/L Al had adverse effects on oocyte maturation by impairing organelle and *** spindle and misaligned chromosomes which might be considered to be caused by elevated levels of acetylation,as well as abnormal distribution of actin dynamics could hinder normal meiosis of *** dysfunction indicated that Al affected proteins synthesis,transport and digestion,which would further damage oocyte *** order to explore the mechanism of Al toxicity,our further investigation demonstrated that Al caused mitochondrial dysfunction and imbalance calcium homeostasis,resulting in limited energy ***,high level of reactive oxygen species,DNA damage and apoptosis caused by oxidative stress were also the manifestation of Al toxicity on *** conclusion,our study provided the evidence that Al exposure affected oocyte quality through its effects on spindle organization,actin dynamics,organelle function and the induction of DNA damage-related apoptosis with mouse model.

关键词： Aluminum Oocyte Cytoskeleton Organelle DNA damage