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Microstructure and properties evolution of in-situ fiber-reinforced Ag-Cu-Ni-Ce alloy during deformation and heat treatment

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International Journal of Minerals,Metallurgy and Materials 2022年第11期29卷 2000-2011页

作者： xingqun he Huadong Fu Jianxin Xie Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Key Laboratory for Advanced Materials Processing(Ministry of Education) University of Science and Technology BeijingBeijing 100083China

Silver-based alloys are significant light-load electrical contact materials(ECMs).The trade-off between mechanical properties and electrical conductivity is always an important issue for the development of silver-based ECMs.In this paper,we proposed an idea for the regulation of the mechanical properties and the electrical conductivity of Ag-11.40Cu-0.66Ni-0.05Ce(wt%)alloy using in-situ composite fiber-reinforcement.The alloy was processed using rolling,heat treatment,and heavy drawing,the strength and electrical conductivity were tested at different deformation stages,and the microstructures during deformation were observed using field emission scanning electron microscope(FESEM),transmission electron microscope(TEM)and electron backscatter diffraction(EBSD).The results show that the method proposed in this paper can achieve the preparation of in-situ composite fiber-reinforced Ag-Cu-Ni-Ce alloys.After the heavy deformation drawing,the room temperature Vickers hardness of the as-cast alloy increased from HV 81.6 to HV 169.3,and the electrical conductivity improved from 74.3%IACS(IACS,i.e.,international annealed copper standard)to 78.6%IACS.As the deformation increases,the alloy strength displays two different strengthening mechanisms,and the electrical conductivity has three stages of change.This research provides a new idea for the comprehensive performance control of high-performance silver-based ECMs.

关键词： silver alloy electrical contact materials drawing in-situ fiber-reinforced

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A rapid and effective method for alloy materials design via sample data transfer machine learning

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npj Computational Materials 2023年第1期9卷 2083-2094页

作者： Lei Jiang Zhihao Zhang Hao Hu xingqun he Huadong Fu Jianxin Xie Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing100083 BeijingChina Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Institute for Advanced Materials and TechnologyUniversity of Science and Technology Beijing100083 BeijingChina Key Laboratory for Advanced Materials Processing(MOE) University of Science and Technology Beijing100083 BeijingChina

One of the challenges in material design is to rapidly develop new materials or improve the performance of materials by utilizing the data and knowledge of existing materials.here,a rapid and effective method of alloy material design via data transfer learning is proposed to efficiently design new alloys using existing data.A new type of aluminum alloy(E2 alloy)with ultra strength and high toughness previously developed by the authors is used as an example.An optimal three-stage solution-aging treatment process(T66R)was efficiently designed transferring 1053 pieces of process-property relationship data of existing AA7xxx commercial aluminum alloys.It realizes the substantial improvement of strength and plasticity of E2 alloy simultaneously,which is of great significance for lightweight of high-end equipment.Meanwhile,the microstructure analysis clarifies the mechanism of alloy performance improvement.This study shows that transferring the existing alloy data is an effective method to design new alloys.

关键词： alloy rapid toughness

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Precision tuning of highly efficient Pt-based ternary alloys on nitrogen-doped multi-wall carbon nanotubes for methanol oxidation reaction

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Journal of Energy Chemistry 2024年第1期88卷 242-251,I0006页

作者： xingqun Zheng Zhengcheng Wang Qian Zhou Qingmei Wang Wei he Shun Lu College of Safety Engineering Chongqing University of Science&TechnologyChongqing 401331China College of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China School of Chemistry and Chemical Engineering Guizhou UniversityGuizhou 550025GuiyangChina Department of Chemistry University of Rhode IslandKingston 02881Rhode IslandUnited States Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

The electrochemical methanol oxidation is a crucial reaction in the conversion of renewable energy.To enable the widespread adoption of direct methanol fuel cells(DMFCs),it is essential to create and engineer catalysts that are both highly effective and robust for conducting the methanol oxidation reaction(MOR).In this work,trimetallic PtCoRu electrocatalysts on nitrogen-doped carbon and multi-wall carbon nanotubes(PtCoRu@NC/MWCNTs)were prepared through a two-pot synthetic strategy.The acceleration of CO oxidation to CO_(2) and the blocking of CO reduction on adjacent Pt active sites were attributed to the crucial role played by cobalt atoms in the as-prepared electrocatalysts.The precise control of Co atoms loading was achieved through precursor stoichiometry.Various physicochemical techniques were employed to analyze the morphology,element composition,and electronic state of the catalyst.Electrochemical investigations and theoretical calculations confirmed that the Pt_(1)Co_(3)Ru_(1)@NC/MWCNTs exhibit excellent electrocatalytic performance and durability for the process of MOR.The enhanced MOR activity can be attributed to the synergistic effect between the multiple elements resulting from precisely controlled Co loading content on surface of the electrocatalyst,which facilitates efficient charge transfer.This interaction between the multiple components also modifies the electronic structures of active sites,thereby promoting the conversion of intermediates and accelerating the MOR process.Thus,achieving precise control over Co loading in PtCoRu@NC/MWCNTs would enable the development of high-performance catalysts for DMFCs.

关键词： Ternary alloys Electrocatalysts Methanol oxidation reaction Electron transfer Theoretical calculations

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Improving the electrocatalytic performances of Pt-based catalysts for oxygen reduction reaction via strong interactions with single-CoN_(4)-rich carbon support

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Chinese Chemical Letters 2024年第5期35卷 265-271页

作者： Jin Long xingqun Zheng Bin Wang Chenzhong Wu Qingmei Wang Lishan Peng Guizhou University Key Laboratory of Green Chemical and Clean Energy Technology Guizhou University Engineering Research Center of Efficient Utilization for Industrial WasteInstitute of Dual-carbon and New Energy Technology Innovation and Development of Guizhou ProvinceSchool of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025China College of Safety Engineering Chongqing University of Science&TechnologyChongqing 401331China Key Laboratory of Rare Earths Chinese Academy of SciencesGanjiang Innovation AcademyGanzhou 341119China

Developing platinum-group-metal(PGM)catalysts possessing strong metal-support interaction and controllable PGM size is urgent for the sluggish oxygen reduction reaction(ORR)in proton-exchange membrane fuel cells.herein,we propose an in-situ self-assembled reduction strategy to successfully induce highly-dispersed sub-3nm platinum nanoparticles(Pt NPs)to attach on resin-derived atomic Co coordinated by N-doped carbon substrate(Pt/Co_(SA)-N-C)for ORR.To be specific,the interfacial electron interaction effect,along with a highly robust Co_(SA)-N-C support endow the as-fabricated Pt/Co_(SA)-N-C catalyst with significantly enhanced catalytic properties,i.e.,a mass activity(MA)of 0.719 A/mgPt at 0.9 ViR-free and a reduction of 24.2%in MA after a 20,000-cycles test.Density functional theory(DFT)calculations demonstrate that the enhanced electron interaction between Pt and Co_(SA)-N-C support decreases the dband center of Pt,which is in favor of lowering the desorption energy of ^(*)OH on Pt/Co_(SA)-N-C surface and accelerating the formation of H_(2)O,thus enhance the instinct activity of ORR.Furthermore,the higher binding energy between Pt and Co_(SA)-N-C compared to Pt and C indicates that the migration of Pt has been suppressed,which theoretically explains the improved durability of Pt/Co_(SA)-N-C.Our work offers an enlightenment on constructing composite Pt-based catalysts with multiple active sites.

关键词： Fuel cells Oxygen reduction reaction Platinum Single-CoN_(4)-rich carbon support Metal-substrate interaction

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A 3D-printed microhemispherical shell resonator with electrostatic tuning for a Coriolis vibratory gyroscope

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Microsystems & Nanoengineering 2024年第2期10卷 25-35页

作者： Baoyin Hou Ye Zhu Chaofan he Weidong Wang Zhi Ding Wen he Yong he Lufeng Che College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China Center for Microelectronics Shaoxing InstituteZhejiang UniversityShaoxing312035China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310058China

The emergence of microhemispherical resonant gyroscopes,which integrate the advantages of exceptional stability and long lifetime with miniaturization,has afforded new possibilities for the development of whole-angle gyroscopes.However,existing methods used for manufacturing microhemispherical resonant gyroscopes based on MEMS technology face the primary drawback of intricate and costly processing.here,we report the design,fabrication,and characterization of the first 3D-printable microhemispherical shell resonator for a Coriolis vibrating gyroscope.We remarkably achieve fabrication in just two steps bypassing the dozen or so steps required in traditional micromachining.By utilizing the intricate shaping capability and ultrahigh precision offered by projection microstereolithography,we fabricate 3D high-aspect-ratio resonant structures and controllable capacitive air gaps,both of which are extremely difficult to obtain via MEMS technology.In addition,the resonance frequency of the fabricated resonators can be tuned by electrostatic forces,and the fabricated resonators exhibit a higher quality factor in air than do typical MEMS microhemispherical resonators.This work demonstrates the feasibility of rapidly batch-manufacturing microhemispherical shell resonators,paving the way for the development of microhemispherical resonator gyroscopes for portable inertial navigation.Moreover,this particular design concept could be further applied to increase uptake of resonator tools in the MEMS community.

关键词： resonator tuning electrostatic

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Chemotherapy induces breast cancer stem cell enrichment through repression of glutathione S-transferase Mu

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Genes & Diseases 2024年第2期11卷 528-531页

作者： Jing he Yiran Yu Yilin he Jie he Guangyu Ji Haiquan Lu The Second Hospital and Advanced Medical Research Institute Cheeloo College of MedicineShandong UniversityJinanShandong 250012China Department of Nursing The First Affiliated Hospital of Shandong First Medical UniversityJinanShandong 250014China School of Medicine Xinjiang Medical UniversityUrumqiXinjiang 830054China School of Medicine Binzhou Medical UniversityYantaiShandong 264003China Oncology Department Jinan Zhangqiu District People's HospitalJinanShandong 250200China Key Laboratory for Experimental Teratology of the Ministry of Education Cheeloo College of MedicineShandong UniversityJinanShandong 250012China Center for Reproductive Medicine Shandong UniversityJinanShandong 250012China

Triple-negative breast cancer(TNBC)has aggressive characteristics as exemplified by the high risk of recurrence,metastasis,and patient mortality.1 Cytotoxic chemotherapy may reduce tumor burden initially,but leave behind chemo-resistant breast cancer stem cells(BCSCs)that lead to tumor recurrence and metastasis.2 Chemotherapy induces BCsC enrichment through the activation of glutathione biosynthesis pathways,which increases intracellular glutathione levels and specifies the BCSC phenotype through complicated downstream signaling pathways.3 Glutathione S-transferases(GSTs),a superfamily(which contains seven cytosolic classes:Alpha,Kappa,Mu,Omega,Pi,Theta,and Zeta,and one microsomal class MGSTs)of phase Il enzymes that catalyze the conjugation of glutathione with electrophilic compounds,play a critical role in detoxification and chemotherapy resistance of cancer cells.However,the role of GSTs in the regulation of BCSCs is largely elusive.

关键词： chemotherapy breast metastasis

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Coupled Numerical Simulation of Electromagnetic and Flow Fields in a Magnetohydrodynamic Induction Pump

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Fluid Dynamics & Materials Processing 2024年第4期20卷 889-899页

作者： he Wang Ying he College of Transportation Ludong UniversityYantai264025China College of Intelligent Manufacturing City College of HuizhouHuizhou516025China

Magnetohydrodynamic(MHD)induction pumps are contactless pumps able to withstand harsh environments.The rate of fluid flow through the pump directly affects the efficiency and stability of the device.To explore the influence of induction pump settings on the related delivery speed,in this study,a numerical model for coupled electromagnetic and flow field effects is introduced and used to simulate liquid metal lithium flow in the induction pump.The effects of current intensity,frequency,coil turns and coil winding size on the velocity of the working fluid are analyzed.It is shown that the first three parameters have a significant impact,while changes in the coil turns have a negligible influence.The maximum increase in working fluid velocity within the pump for the parameter combination investigated in this paper is approximately 618%.As the frequency is increased from 20 to 60 Hz,the maximum increase in the mean flow rate of the working fluid is approximately 241%.These research findings are intended to support the design and optimization of these devices.

关键词： Magnetic fluid multi-physical field coupling induction pump numerical simulation liquid metal conveying

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机器学习辅助高性能银合金电接触材料的快速发现

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金属学报 2022年第6期58卷 816-826页

作者：何兴群付华栋张洪涛方继恒谢明谢建新北京科技大学北京材料基因工程高精尖创新中心北京100083 北京科技大学现代交通金属材料与加工技术北京实验室北京100083 北京科技大学材料先进制备技术教育部重点实验室北京100083 昆明贵金属研究所稀贵金属综合利用新技术国家重点实验室昆明650106

为了快速发现高性能银合金电接触材料,从文献中收集了32组铸造法制备的银合金电接触材料的成分和性能数据,采用特征量筛选方法识别出影响合金性能的关键合金因子,采用支持向量机算法建立了合金导电率和硬度预测模型,实现了合金成分的快... 详细信息

为了快速发现高性能银合金电接触材料,从文献中收集了32组铸造法制备的银合金电接触材料的成分和性能数据,采用特征量筛选方法识别出影响合金性能的关键合金因子,采用支持向量机算法建立了合金导电率和硬度预测模型,实现了合金成分的快速设计。选取预测性能优异的Ag-19.53Cu-1.36Ni、Ag-10.20Cu-0.20Ni-0.05Ce和Ag-11.43Cu-0.66Ni-0.05Ce (质量分数,%) 3种成分设计方案进行工业生产条件的实验验证,性能预测结果与实验结果误差均小于10%,3种合金导电率均≥79%IACS,Vickers硬度均≥87 HV,综合性能均优于已有铸造法制备的银合金电接触材料。上述研究结果表明,本工作建立的机器学习成分设计方法可靠性好,有助于提高合金成分设计效率,快速发现综合性能优异的银合金电接触材料。

关键词：机器学习银合金电接触材料成分设计

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Honeycomb-like biochar framework coupled with Fe_(3)O_(4)/FeS nanoparticles as efficient heterogeneous Fenton catalyst for phenol degradation

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Journal of Environmental Sciences 2024年第2期136卷 390-399页

作者： Aihua Cheng Yi he Xiaohe Liu Chi he Department of Environmental Engineering College of Geology and EnvironmentXi’an University of Science and TechnologyXi’an 710054China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China National Engineering Laboratory for VOCs Pollution Control Material and Technology University of Chinese Academy of SciencesBeijing 101408China

Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater treatment.here,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by pyrolysis.The prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the reaction.Moreover,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation efficiency.Further,biochar can effectively promote cycling stability by limiting Fe leaching.This work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.

关键词： Biomass Biochar Fenton reaction Fe_(3)O_(4)/FeS(Fe/S) Phenol degradation

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Regulation of insect behavior by non-coding RNAs

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Science China(Life Sciences) 2024年第6期67卷 1106-1118页

作者： Jing he Le Kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institutes of Life Sciences Chinese Academy of SciencesBeijing 100101China College of Life Science Hebei UniversityBaoding 071002China

The adaptation of insects to environments relies on a sophisticated set of behaviors controlled by molecular and physiological processes.Over the past several decades,accumulating studies have unveiled the roles of non-coding RNAs(nc RNAs)in regulating insect behaviors.nc RNAs assume particularly pivotal roles in the behavioral plasticity of insects by rapidly responding to environmental stimuli.nc RNAs also contribute to the maintenance of homeostasis of insects by fine-tuning the expression of target genes.However,a comprehensive review of nc RNAs'roles in regulating insect behaviors has yet to be conducted.here,we present the recent progress in our understanding of how nc RNAs regulate various insect behaviors,including flight and movement,social behavior,reproduction,learning and memory,and feeding.We refine the intricate mechanisms by which nc RNAs modulate the function of neural,motor,reproductive,and other physiological systems,as well as gene expression in insects like fruit flies,social insects,locusts,and mosquitos.Furthermore,we discuss potential avenues for future studies in nc RNA-mediated insect behaviors.

关键词： ncRNAs insect behavior plasticity fine-tuning environmental adaptation

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