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Intelligent Small Sample Defect Detection of Concrete Surface Using Novel Deep Learning Integrating Improved YOLOv5

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 545-547页

作者： Yongming Han Lei wang youqing wang Zhiqiang Geng IEEE College of Information Science and Technology Beijing University of Chemical TechnologyBeijing 100029 Engineering Research Center of Intelligent PSE Ministry of Education in ChinaBeijing 100029China

Dear Editor,This letter presents an intelligent small sample defect detection of concrete surface using novel deep learning integrating the improved YOLOv5 based on the Wasserstein GAN(WGAN)enhancement algorithm.The proposed method is capable of producing top-notch data sets to address the issues of insufficient samples and substandard quality.

关键词： concrete integrating algorithm

Enhanced visible-light photocatalytic hydrogen evolution using two-dimensional carbon nitride sheets with the removal of amine groups

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Chinese Chemical Letters 2024年第2期35卷 446-450页

作者： Yu Zhang Liting Wu Shaopeng wang Dingyi Yang Huan Liang Yizhang Wu Jian Hao youqing wang Jianke Liu Yong wang Department of Physics Shaanxi University of Science and TechnologyXi'an 710021China School of Advanced Materials and Nanotechnology Academy of Advanced Interdisciplinary ResearchXidian UniversityXi'an 710126China The State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology Xidian UniversityXi'an 710126China Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructuresNanjing UniversityNanjing 210093China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China

Two-dimensional(2D)carbon nitride sheets(CNs)with atomically thin structures are regarded as one of the most promising materials for solar energy conversion.However,due to their substantially enlarged bandgap caused by the strong quantum size effect and their incomplete polymerisation with a large number of non-condensed surface amino groups,the practical applicability of CNs in photocatalysis is limited.In this study,CNs with broad visible-light absorption were synthesised using a 5-min fast thermal annealing.The removal of uncondensed amine groups reduces the bandgap of CNs from 3.06 eV to 2.60 eV,increasing their absorption of visible light.Interestingly,the CNs were distorted after annealing,which can differentiate the spatial positions of electrons and holes,enhancing the visible-light absorption efficiency.As a result,when exposed to visible light,the photocatalytic hydrogen production activity of atomically thin 2D CNs rose by 8.38 times.This research presents a dependable and speedy method for creating highly effective visible-light photocatalysts with narrowed bandgaps and improved visible-light absorption.

关键词： 2D carbon nitride sheets Rapid thermal annealing DFT calculations Visible-light absorption visible-light photocatalysis

Distributed Secure State Estimation of Multi-Agent Systems Under Homologous Sensor Attacks

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IEEE/CAA Journal of Automatica Sinica 2023年第1期10卷 67-77页

作者： Yukun Shi youqing wang Jianyong Tuo the College of Information Science and Technology Beijing University of Chemical TechnologyBeijing 100029China IEEE

This paper addresses the problem of distributed secure state estimation for multi-agent systems under homologous sensor attacks.Two types of secure Luenberger-like distributed observers are proposed to estimate the system state and attack signal simultaneously.Specifically,the proposed two observers are applicable to deal with the cases in the presence and absence of time delays during network communication.It is also shown that the proposed observers can ensure the attack estimations from different agents asymptotically converge to the same value.Sufficient conditions for guaranteeing the asymptotic convergence of the estimation errors are derived.Simulation examples are finally provided to demonstrate the effectiveness of the proposed results.

关键词： Consensus-based Luenberger-like observer distributed secure state estimation homologous signal

Hydrophobic modification of polysaccharides and the construction and properties of their micelles:a review of applications in the field of biomedicine

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Science China Chemistry 2024年第6期67卷 1881-1903页

作者： Dayang wang Xiaohua Li Huanchen Yao Xin Liu Yan Gao Hailin Cong Bing Yu youqing Shen College of Chemistry and Chemical Engineering College of Life SciencesCollege of Materials Science and EngineeringInstitute of Biomedical Materials and EngineeringQingdao UniversityQingdao266071China State Key Laboratory of Bio-Fibers and Eco-Textiles Qingdao UniversityQingdao266071China School of Materials Science and Engineering Shandong University of TechnologyZibo255000China Key Laboratory of Biomass Chemical Engineering of Ministry of Education Center for Bionanoengineeringand Department of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China

Nanomedicine delivery technology plays an important role in modern medicine and has shown good therapeutic effects in scientific research.Polysaccharides have the characteristics of wide sources,excellent biocompatibility,and non-toxicity.In addition,there are multifunctional groups on the main chain of polysaccharides,which can be surface-modified or functionalized to have targeting ability through specific sugar parts.Amphiphilic polysaccharide micelles with good biocompatibility,degradability,high safety,easy structural modification,and special core-shell structure are regarded as ideal carriers for nanomedicines.Therefore,this review is focused on the hydrophobic modification designs of polysaccharides,the preparation methods and characteristics of micelles,and the applications of amphiphilic polysaccharide micelles in the field of biomedicine.It is expected to provide some ideas and inspiration for the design of polysaccharide drug carriers.

关键词： polysaccharide hydrophobic modification micelle drug delivery biomedicine

Electron-distribution control via Pt/NC and MoC/NC dual junction:Boosted hydrogen electro-oxidation and theoretical study

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Journal of Energy Chemistry 2024年第1期88卷 513-520,I0011页

作者： Feng Zhou Xiaofeng Ke Yihuang Chen Mei Zhao Yun Yang youqing Dong Chao Zou Xi’an Chen Huile Jin Lijie Zhang Shun wang Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000ZhejiangChina Zhejiang Engineering Research Center for Electrochemical Energy Materials and Devices Institute of New Materials&Industry TechnologyWenzhou UniversityWenzhou 325000ZhejiangChina

The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to modulate its catalytic HOR performance,but at the cost of mass activity due to the coverage of modifiers on Pt surface.Herein,we constructed dual junctions'Pt/nitrogen-doped carbon(Pt/NC)andδ-MoC/NC to modify electronic structure of Pt via interfacial electron transfer to acquire Pt-MoC@NC catalyst with electron-deficient Pt nanoparticles,simultaneously endowing it with high mass activity and durability of alkaline HOR.Moreover,the unique structure of Pt-MoC@NC endows Pt with a high COtolerance at 1,000 ppm CO/H_(2),a quality that commercial Pt-C catalyst lacks.The theoretical calculations not only confirm the diffusion of electrons from Pt/NC to Mo C/NC could occur,but also demonstrate the negative shift of Pt d-band center for the optimized binding energies of*H,*OH and CO.

关键词： Hydrogen oxidation reaction Dual junctions CO-tolerance Platinum

Effect of excitation frequency on characteristics of mixture discharge in fast-axial-flow radio frequency-excited carbon dioxide laser

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Frontiers of Optoelectronics 2016年第4期9卷 592-598页

作者： Heng ZHAO Bo LI Wenjin wang Yi HU youqing wang School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan 430074 china

A one-dimensional fluid model has been used to describe the effect of radio frequency （RF） on the characteristics of carbon dioxide （CO2）, nitrogen （N2） and helium （He） mixture discharge at 120 mbar in fast-axial- flow RF-excited CO2 laser. A finite difference method was applied to solve the one-dimensional fluid model. The simulation results show that the spatial distributions of electron density and current density rely strongly on the modulating driven frequency. When the excitation fre- quency changes from 5 to 45 MHz, the plasma discharge is always in a mode. Moreover, as the excitation frequency increasing, the higher densities of COv and N2vib can be obtained, which is important to get higher excitation efficiency for the upper laser level.

关键词： plasma numerical simulation CO2/He/N2mixtre discharges one-dimensional fluid model

Water cooling radiator for solid state power supply in fast-axial-flow C02 laser

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Frontiers of Optoelectronics 2016年第4期9卷 585-591页

作者： Heng ZHAO Bo LI Wenjin wang Yi HU youqing wang National Engineering Research Center for Laser Processing School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan 430074 China

Two different flow channel configurations on thermal resistances associated with the behavior of cooling of power device were studied in this paper. ANSYS Icepak 14.0 has been adopted as a numerical simulation tool. The simulation results from this study showed that the shapes of channels in cooling radiator play an important role in the thermal management of water cooling radiation system. The optimal channel design could improve the heat- dissipating efficiency by 80% in water cooling radiation system. The result also indicated that the thermal resistance of heat sinks decreased with the volumetric flow rate and the number of cylindrical columns in the flow channel. Experimental results were obtained under certain channel configurations and volume rates. Moreover, the results of numerical simulation can be explained well by the experimental results.

关键词： heat spreader water cooling turbulencegenerator Icepak software

Assessment of tree-ring mercury radial translocation and age effect in Masson pine:Implications for historical atmospheric mercury reconstruction

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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： Xu Liu Xun wang Dingyong wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the reliability.In this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at Mt.Jinyun in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric Hg.Results showed that distinct variabilities among Masson pine tree-ring Hg concentration profiles.The Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric Hg.We found a distinct age effect that the tree ring of young trees had the higher Hg concentration.Besides,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree rings.The modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in Chongqing.We finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

压弯剪扭复合作用下灌浆套筒装配式RC墩的抗震性能

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湖南大学学报（自然科学版） 2024年第3期51卷 182-192页

作者：林友勤赖仕永夏樟华王达荣福州大学土木工程学院福建福州350108 福建省交通规划设计研究院有限公司福建福州350001

随着城市交通的快速发展,对其建设要求越来越高,城市桥梁主要为匝道桥、斜交桥等非规则桥梁.为得到压弯剪扭等复合地震作用下装配式墩的损伤机理和滞回特性,进行了灌浆套筒连接(Grouting Sleeve,GS)、灌浆套筒和钢管混凝土剪力键组合连... 详细信息

随着城市交通的快速发展,对其建设要求越来越高,城市桥梁主要为匝道桥、斜交桥等非规则桥梁.为得到压弯剪扭等复合地震作用下装配式墩的损伤机理和滞回特性,进行了灌浆套筒连接(Grouting Sleeve,GS)、灌浆套筒和钢管混凝土剪力键组合连接(Grouting Sleeve and Steel-tube,GSS)装配式墩和钢筋混凝土现浇(Reinforced Concrete,RC)墩等三种桥墩在压弯剪扭复合作用下的拟静力试验.结合现有混凝土结构设计规范计算剪扭相关曲线,并与试验结果进行对比,分析装配式墩复合荷载作用下的剪扭承载能力.结果表明:GS构件与RC构件以压弯扭破坏为主,而插入钢管剪力键的GSS构件则发生塑性铰上移,呈现出剪扭破坏的特征.GS构件和RC构件具有较好的弯曲耗能能力,增加钢管剪力键的GSS构件则可以提升抗弯承载力.装配式墩接头导致其整体性较弱,GS构件和GSS构件抗扭承载力小于RC构件.各构件在复合荷载作用下的剪扭相关关系接近规范中的1/4圆理论曲线,研究结果可以为灌浆套筒连接装配式墩在压弯剪扭复合作用下的抗震性能分析提供参考.

关键词：桥梁工程装配式墩灌浆套筒连接拟静力试验压弯剪扭承载力延性