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Ferroelectric-controlled graphene plasmonic surfaces for all-optical neuromorphic vision

Science China(Technological Sciences) 2024年第3期67卷 765-773页

作者： CHEN JianBo LIU yu LI ShangDong lin lin LI YaDong HUAng Wen GUO JunXiong School of Electronic Information and Electrical Engineering Institute for Advanced StudyChengdu UniversityChengdu 610106China School of Integrated Circuits Tsinghua UniversityBeijing 100084China School of Integrated Circuits(National Exemplary Schoolof Microelectronics) Universityof Electronic Science and Technologyof China Chengdu 610054China Jincheng Research Institute of Opto-mechatronics Industry Jincheng 048000China Shanxi Key Laboratory of Advanced Semiconductor Optoelectronic Devices and Integrated Systems Jincheng 048000China Engineering Research Center of Digital Imaging and Display Ministry of EducationSoochow UniversitySuzhou 215006China

Artificial visual systems can recognize desired objects and information from complex environments, and are therefore highly desired for pattern recognition, object detection, and imaging applications. However, state-of-the-art artificial visual systems with high recognition performances that typically consist of electronic devices face the challenges of requiring huge storage space and high power consumption owing to redundant data. Here, we report a terahertz(THz) frequency-selective surface using a graphene split-ring resonator driven by ferroelectric polarization for efficient visual system applications. The downward polarization of the ferroelectric material offers an ultrahigh electrostatic field for dop.ng p-type graphene with an anticipated Fermi level. By optimizing the geometric parameters of the devices and modulating the carrier behaviors of graphene, our plasmonic devices exhibit a tunable spectral response in a range of 1.7–6.0 THz with continuous transmission values. The alloptical neural network using graphene plasmonic surfaces designed in this study exhibited excellent performance in visual preprocessing and convolutional filtering and achieved an ultrahigh recognition accuracy of up to 99.3% in training the Modified National Institute of Standards and Technology(MNIST) handwritten digit dataset. These features demonstrate the great potential of graphene plasmonic devices for future smart artificial vision systems.

关键词： graphene plasmon ferroelectric frequency selective surface artificial vision system

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Recent Advances in Mechanistic Understanding of Metal-Free Carbon Thermocatalysis and Electrocatalysis with Model Molecules

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Nano-Micro Letters 2024年第7期16卷 74-97页

作者： Wei Guo linhui yu ling Tang Yan Wan Yangming lin CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Xiamen Key Laboratory of Rare Earth photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021People’s Republic of China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Institute of Urban Environment Chinese Academy of SciencesXiamen 361021People’s Republic of China

Metal-free carbon,as the most representative heterogeneous metal-free catalysts,have received considerable interests in electro-and thermo-catalytic reac-tions due to their impressive performance and *** the past decade,well-designed carbon catalysts with tunable structures and heteroatom groups coupled with various characterization techniques have proposed numerous reaction ***,active sites,key intermediate species,precise structure-activity relationships and dynamic evolution processes of carbon catalysts are still rife with controversies due to the monotony and limitation of used experimental *** this Review,we sum-marize the extensive efforts on model catalysts since the 2000s,particularly in the past decade,to overcome the influences of material and structure limitations in metal-free carbon *** both nanomolecule model and bulk model,the real contribution of each alien species,defect and edge configuration to a series of fundamentally important reactions,such as thermocatalytic reactions,electrocatalytic reactions,were systematically *** with in situ techniques,isotope labeling and size control,the detailed reaction mechanisms,the precise 2D structure-activity relationships and the rate-determining steps were revealed at a molecular ***,the outlook of model carbon catalysis has also been proposed in this work.

关键词： Metal-free carbon catalysts Model catalyst Electrocatalysis Active site Reaction mechanisms

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Core shift limitation in investment casting process of hollow turbine blade

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Chinese Journal of Aeronautics 2024年第8期37卷 513-526页

作者： Kang CUI lin JIng Ruisong JIAng Longnv yu Xiao GAO Automation and Software Engineering Shanxi UniversityTaiyuan 030006China Key Laboratory of High performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologySchool of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China School of Mechanical Engineering Sichuan UniversityChengdu 610065China

The deviation in wall thickness caused by core shift during the investment casting process significantly impacts the strength and service life of hollow turbine *** address this issue,a core shift limitation method is developed in this ***,a shift model is established based on computational fluid dynamics and motion simulation to predict the movement of the ceramic core in investment casting ***,utilizing this model,an optimization method for fixturing layout inside the refractory ceramic shell is devised for the ceramic *** casting experiment demonstrates that by utilizing the optimized fixture layout,not only can core shift during the investment casting pouring process be effectively controlled,but also the maximum wall thickness error of the blade can be reduced by 42.02%.In addition,the core shift prediction is also validated,with a prediction error of less than 26.9%.

关键词： Hollow turbine blade Wall thickness Ceramic core Shift prediction Fixturing layout optimization

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High-Superelasticity NiTi Shape Memory Alloy by Directed Energy Deposition-Arc and Solution Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 132-144页

作者： Junyi Ma lin yu Qing Yang Jie Liu Lei Yang State Key Laboratory of Materials processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430070China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan430074China

Directed energy deposition-arc(DED-Arc)technology has the advantages of simple equipment,low manufacturing cost and high deposition rate,while the use of DED-Arc has problems of microstructure inhomogeneity,position dependence of macroscopic mechanical properties and ***,it is necessary to carry out a subsequent heat treatment to improve its microstructure uniformity,mechanical properties and *** this investigation,the DED-Arc 15-layer NiTi alloy thin-walled parts with the solution treatment at different process parameters were studied to analyze the effects of solution heat treatment on microstructure,phase composition,phase transformation,microhardness,tensile and *** temperature range of solution treatment is 800-1050℃,and the treatment time range is 1-5.5 *** results show that after solution treatment at 800℃/1 h,the content of precipitated phase decreases,the grain is refined,the microhardness increases,and the mechanical properties in the 0°direction are *** strain recovery rate after 10 tensile cycles has increased from 37.13%(as-built)to 49.25%(solid solution treatment).This research provides an effective post treatment method for high-performance DED-Arc NiTi shape memory alloys.

关键词： Directed energy deposition-arc(DED-Arc) Cold metal transfer(CMT) NiTi shape memory alloys Microstructure phase transformation Solution heat treatment

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UiO-66-NH_(2)nanoparticles supported on layered double hydroxides as an excellent adsorbent for levofloxacin capture

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particuology 2024年第9期92卷 155-165页

作者： Yan Li Heng lin Qiaolan yu Na Ma Wei Dai College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua321004China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua321004China

The adsorption performances of individual adsorbent such as UiO-66-NH_(2)and MgAl-layered double hydroxides(MgAl-LDH)toward levofloxacin(LVX)is less satisfactory due to the disappointing uptake capacity and adsorption ***,a 3D flower-like composite adsorbent prepared via iterative hydrothermal synthesis method anchoring UiO-66-NH_(2)nanoparticles onto the MgAl-LDH *** to the synergistic effects of UiO-66-NH_(2),and MgAl-LDH,the MgAl-LDH@UiO-66-NH_(2)exhibits an outstanding adsorption performance toward ***,the maximum LVX uptake capacity over MgAl-LDH@UiO-66-NH_(2)reached 268 mg/g,which was higher than that of the individual adsorption materials UiO-66-NH_(2)(41 mg/g),MgAl-LDH(140 mg/g),and some adsorbents reported in previous *** rapid adsorption process can reach equilibrium within 20 min,which conformed well to the pseudo-second-order kinetics and the Langmuir isotherm *** thermodynamic result also indicated that the adsorption was spontaneous and exothermic,simultaneous coexisting physical and chemical adsorption ***,the MgAl-LDH@UiO-66-NH_(2)still maintained excellent adsorption capacity with a slightly decrease after fifth cycle,exhibiting a remarkable reuse and stable *** work provides a highly novel strategy to prepare recyclable composite adsorbent for the LVX capture from aqueous solution.

关键词： Layered double hydroxides UiO-66-NH_(2) LVX Adsorption

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Comparison of models to predict air infiltration rate of buildings with different surrounding environments

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Building Simulation 2024年第6期17卷 1007-1021页

作者： Shu Zheng Xiujiao Song lin Duanmu yu Xue Xudong Yang Department of Building Science Tsinghua UniversityBeijing100084China School of Civil Engineering Dalian University of TechnologyDalian116024China Shanxi Research Institute for Clean Energy Tsinghua UniversityTaiyuan030032China

The air infiltration rate of buildings strongly influences indoor environment and energy *** this study,several traditional methods for determining the air infiltration rate were compared,and their accuracy in different scenarios was ***,a method combining computational flow dynamics(CFD)with the Swami and Chandra(S-C)model was developed to predict the influence of the surrounding environment on the air infiltration *** buildings in Dalian,China,were selected:one with a simple surrounding environment and the other with a complex surrounding environment;their air infiltration rates were *** test results were used to validate the accuracy of the air infiltration rate solution models in different urban *** the building with a simple environment,the difference between the simulation and experimental results was 0.86%–22.52%.For the building with a complex environment,this difference ranged from 17.42%to 159.28%.We found that most traditional models provide accurate results for buildings with simple surrounding and that the simulation results widely vary for buildings with complex *** results of the method of combining CFD with the S-C model were more accurate,and the relative error between the simulation and test results was 10.61%.The results indicate that the environment around the building should be fully considered when calculating the air infiltration *** results of this study can guide the application of methods of determining air infiltration rate.

关键词： air infiltration rate models CFD simulation building surrounding air infiltration rate test

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Joined AZ31B Magnesium Alloys with Ag Interlayer by Ultrasonic-Induced Transient Liquid phase Bonding in Air

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1177-1185页

作者： Qian Wang p.ng yu Haoran lin Chongzhi Guo Xiaoqiang Hu Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China School of Rare Earths University of Science and Technology of ChinaHefei230026China Shenyang 7D New Materials Equipment Co.LTD. Shenyang110076China Shenyang National Laboratory of Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

AZ31B magnesium alloys are commonly used in lightweight structures of automobile and aerospace *** this work,the ultrasonic-induced transient liquid phase bonding technique is deployed to joint AZ31B magnesium alloys at 490℃ with Ag interlayer in the *** effect of ultrasonic vibration on microstructure and mechanical properties of welding seam is *** vibration duration increases,the width of the welding seam increases firstly and then *** the ultrasound vibration sustained for one second,the eutectic reaction occurred in the contacting interface between Ag interlayer and the base metal AZ31B,resulting in formation of liquid phase and metallurgical *** the ultrasound vibration sustained for seven second,the width of the welding seam increased to a maximum of about 303.1μm and the average shear bond strength of the welding joint attained the peak value of about 66.87 *** the ultrasound vibration sustained over seven seconds,the liquid phase is gradually squeezed out and the width of the welding seam decreases.α-Mg and AgMg_(3) can be observed in the welding *** analysis shows thatα-Mg has a certain strengthening *** whole process of appearance,growth and integration ofα-Mg is analyzed.

关键词： Ultrasonic bonding Magnesium alloy Silver Microstructure Intermetallic compound

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Quantifying the Role of the Eddy Transfer Coefficient in Simulating the Response of the Southern Ocean Meridional Overturning Circulation to Enhanced Westerlies in a Coarse-resolution Model

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Advances in Atmospheric Sciences 2024年第9期41卷 1853-1867页

作者： Yiwen LI Hailong LIU p.ngfei lin Eric pCHASSIGNET Zip.ng yu Fanghua WU School of Ocean Sciences China University of GeosciencesBeijing 100083China Laoshan Laboratory Qingdao 266237China Institute of Atmospheric physics Chinese Academy of SciencesBeijing 100029China Center for Ocean-Atmospheric prediction Studies Florida State UniversityTallahassee 32306FloridaUSA China Meteorological Administration Beijing 100081China

This study assesses the capability of a coarse-resolution ocean model to replicate the response of the Southern Ocean Meridional Overturning Circulation(MOC) to intensified westerlies,focusing on the role of the eddy transfer coefficient(κ).κ is a parameter commonly used to represent the velocities induced by unresolved *** findings reveal that a stratification-dependent κ,incorporating spatiotemporal variability,leads to the most robust eddy-induced MOC response,capturing 82% of the reference eddy-resolving *** the eddy-induced velocity into its vertical variation(VV) and spatial structure(SS) components unveils that the enhanced eddy compensation response primarily stems from an augmented SS term,while the introduced VV term weakens the ***,the temporal variability of the stratification-dependent κ emerges as a key factor in enhancing the eddy compensation response to intensified *** experiment with stratification-dependent κ exhibits a more potent eddy compensation response compared to the constant κ,attributed to the structure of κ and the vertical variation of the density *** results underscore the critical role of accurately representing κ in capturing the response of the Southern Ocean MOC and emphasize the significance of the isopycnal slope in modulating the eddy compensation mechanism.

关键词： eddy transfer coefficient mesoscale eddy parameterization enhanced westerlies Southern Ocean Meridional Overturning Circulation ocean model

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Closed-form solution to the dynamic programming for a heavy-duty parallel hybrid vehicle energy management

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Journal of Control and Decision 2024年第1期11卷 107-116页

作者： Tao Zhang Zhongjun yu Huangda lin National Key Laboratory for Vessel Integrated power System Technology Naval University of EngineeringWuhanPeople’s Republic of China

Dynamic programming(Dp)is frequently used to obtain the optimal solution to the hybrid electric vehicle(HEV)energy *** trade-off between the accuracy and the computational effort is the biggest problem for the Dp *** closed-form solution to the Dp is proposed to solve this ***,the affine linear model of the engine fuel rate is obtained based on engine test *** piecewise linear approximation of the motor power demand is obtained considering the different energy flows in the charging and discharging stages of the ***,the second-order Taylor expansion for the cost matrix at each time and state grid point is introduced to get the closed-form solution of the optimal torque *** results show that this method can greatly reduce the computing burden by 93%while ensuring near-optimal fuel economy compared with the conventional Dp method.

关键词： Dynamic programming energy management closed-form solutions fuel economy hybrid electric vehicles

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Serum monoterpene levels, glucose homeostasis, lipid profiles, and metabolic syndrome in adults: NHANES, 2013–2014

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Emerging Contaminants 2024年第2期10卷 33-39页

作者： Wei-Jie Wang yu-ling lin Chikang Wang Chien-yu lin Division of Nephrology Department of Internal MedicineTaoyuan General HospitalMinistry of Health and WelfareTaoyuan330TaiwanChina Department of Biomedical Engineering Chung Yuan Christian UniversityTaoyuan300TaiwanChina Department of Nephrology Hsinchu Cathay General HospitalHsinchu300TaiwanChina Department of Healthcare Management Yuanpei University of Medical TechnologyHsinchu300TaiwanChina Department of Environmental Engineering and Health Yuanpei University of Medical TechnologyHsinchu300TaiwanChina Department of Internal Medicine En Chu Kong HospitalNew Taipei City237TaiwanChina School of Medicine Fu Jen Catholic UniversityNew Taipei City242TaiwanChina

Monoterpenes are organic compounds which have been studied for their medicinal ***,the association between monoterpene exposure and metabolic parameters in humans is *** investigated the connection between three specific monoterpenes(α-pinene,β-pinene,and limonene),glucose homeostasis biomarkers,lipid profiles,and metabolic syndrome(MS)in 1627 adults from the National Health and Nutrition Examination Survey(NHANES)2013–*** found serum levels ofα-pinene andβ-pinene were positively associated with fasting glucose,total cholesterol,triglyceride,and apolipoprotein *** addition,increased levels of limonene andΣmonoterpene(sum of three monoterpene chemicals)were linked to higher insulin,β-cell function,total cholesterol,low density lipoprotein cholesterol(LDL-C),triglycerides,and apolipoprotein *** with all three monoterpenes above the 50th percentile had notably higher values for total cholesterol and triglycerides compared to those with all three monoterpenes below the 50th percentile(p for trendng MS,higher serum concentrations ofα-pinene were linked to an increased risk of high-density lipoprotein cholesterol(HDL-C)insufficiency and *** concentrations ofβ-pinene were associated with a higher prevalence of ***,increased levels of limonene andΣmonoterpene were connected to a higher risk of MS,larger waist circumference,low HDL-C,hypertriglyceridemia,and higher blood pressure according to MS *** conclusion,serum monoterpenes levels were linked to glucose regulation,lipid profiles,and indicators of *** studies are necessary to clarify the potential causal relationships.

关键词： Glucose homeostasis Lipid profiles Monoterpenes National health and nutrition examination survey(NHANES)

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