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Green Energy & Environment 2023年第3期8卷 904-914页

作者： Shuairen Qian Yuxin Chen Binhang Yan Yi cheng Department of Chemical Engineering Tsinghua UniversityBeijing100084China

High activity and productivity of MoVNbTeO_(x) catalyst are challenging tasks in oxidative dehydrogenation of ethane(ODHE)for industrial application.In this work,phase-pure M1 with 30 wt%CeO_(2) composite catalyst was treated by oxygen plasma to further enhance catalyst performance.The results show that the oxygen vacancies generated by the solid-state redox reaction between M1 and CeO_(2) capture active oxygen species in gas and transform V^(4+)to V^(5+)without damage to M1 structure.The space-time yield of ethylene of the plasma-treated catalyst was significantly increased,in which the catalyst shows an enhancement near~100% than that of phase-pure M1 at 400℃ for ODHE process.Plasma treatment for catalysts demonstrates an effective way to convert electrical energy into chemical energy in catalyst materials.Energy conversion is achieved by using the catalyst as a medium.

关键词： Oxidative dehydrogenation of ethane(ODHE) MoVNbTeO_(x) Composite catalyst Oxygen plasma Energy conversion

Modulatory effects of transcutaneous auricular vagus nerve stimulation (taVNS) on attentional processes

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General Psychiatry 2023年第6期36卷 512-522页

作者： Yuxin Chen Haoyu Yang Faguang Wang Xuejing Lu Li Hu CAS Key Laboratory of Mental Health Institute of PsychologyChinese Academy of SciencesBeijingChina Department of Psychology Universityof ChineseAcademy of SciencesBeijingChina School of Intelligent Manufacturing Wenzhou PolytechnicWenzhouZhejiangChina

Background The modulatory effect of transcutaneous auricular vagus nerve stimulation(taVNS)on attention has varied in previous studies.This inconsistency might be attributed to the combined influence of the modulation effect on the different attentional functions,including alerting,orienting and executive control.Aims We aimed to preliminarily examine the modulatory effectsoftaVNS on differentattentionalfunctions.Methods Fifty-nine healthy participants were recruited and were randomly assigned to taVNS(receiving taVNS for 20 minutes)or control(receiving taVNS for 30 seconds)groups.All participants underwent a dot-probe task before and after the taVNS/control intervention.Their behavioural performance and electroencephalographic signals during pre-and post-tests were recorded,and different observed variables were extracted and analysed to characterise different attentional systems.Results We observed that active taVNS applied at the left ear significantly improved the overall behavioural performance,that is,shorter reaction time(RT)and lower intra-individual reaction time variability(lIRTV)for right-hand responses when compared with the control condition.In addition,active taVNS resulted in larger P3 and movement-related cortical potential(MRCP)amplitudes associated with right-hand reactions than the control condition.Active taVNS also decreased the difference between the pre-and post-tests in the power spectral density of spontaneous high-αband oscillations at C4 electrode.Importantly,parallel mediation models for right-hand responses showed that the change of P3 amplitude mediated the effects of taVNS on RT and lIRTV.In contrast,the change of MRCP amplitude suppressed the effect of taVNS on the lIRTV.Conclusions Our results provided behavioural and brain evidence supporting the effects of taVNS on different attentional systems,and their interaction further shaped behavioural performance,suggesting a promising role of taVNS in cognitive enhancement.

关键词： stimulation vagus behaviour

Predicting the Thickness of an Excavation Damaged Zone around the Roadway Using the DA-RF Hybrid Model

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2507-2526页

作者： Yuxin Chen Weixun Yong Chuanqi Li Jian Zhou School of Resources and Safety Engineering Central South UniversityChangsha410083China Laboratory 3SR CNRS UMR 5521Grenoble Alpes UniversityGrenoble38000France

After the excavation of the roadway,the original stress balance is destroyed,resulting in the redistribution of stress and the formation of an excavation damaged zone(EDZ)around the roadway.The thickness of EDZ is the key basis for roadway stability discrimination and support structure design,and it is of great engineering significance to accurately predict the thickness of EDZ.Considering the advantages of machine learning(ML)in dealing with high-dimensional,nonlinear problems,a hybrid prediction model based on the random forest(RF)algorithm is developed in this paper.The model used the dragonfly algorithm(DA)to optimize two hyperparameters in RF,namely mtry and ntree,and used mean absolute error(MAE),rootmean square error(RMSE),determination coefficient(R^(2)),and variance accounted for(VAF)to evaluatemodel prediction performance.A database containing 217 sets of data was collected,with embedding depth(ED),drift span(DS),surrounding rock mass strength(RMS),joint index(JI)as input variables,and the excavation damaged zone thickness(EDZT)as output variable.In addition,four classic models,back propagation neural network(BPNN),extreme learning machine(ELM),radial basis function network(RBF),and RF were compared with the DA-RF model.The results showed that the DARF mold had the best prediction performance(training set:MAE=0.1036,RMSE=0.1514,R^(2)=0.9577,VAF=94.2645;test set:MAE=0.1115,RMSE=0.1417,R^(2)=0.9423,VAF=94.0836).The results of the sensitivity analysis showed that the relative importance of each input variable was DS,ED,RMS,and JI from low to high.

关键词： Excavation damaged zone random forest dragonfly algorithm predictive model metaheuristic optimization

Marching towards flexible intelligent materials

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Science China Materials 2022年第8期65卷 1991-1993页

作者： yuxin Tang Xiaodong chen College of Chemical Engineering Fuzhou UniversityFuzhou 350116China Innovative Centre for Flexible Devices(iFLEX) Max Planck-NTU Joint Lab for Artificial SensesSchool of Materials Science and EngineeringNanyang Technological University50 Nanyang AvenueSingapore 639798Singapore Institute of Materials Research and Engineering the Agency for ScienceTechnology and Research2 Fusionopolis WayInnovis#08-03138634Singapore

Our society is transforming into more intelligent eco-systems that seamlessly merge human beings,machines,the internet,and energy.The unprecedented momentum in such dramatic transformation inevitably relies on innovation in smarter materials.Flexible intelligent materials are eagerly demanded in such evolution.Flexible intelligent materials are soft materials whose properties can be altered by external stimuli.

关键词： Marching evolution internet

Development of a high-performance green Fe-Al_(2)O_(3)composites using Bayan Obo minerals:Enhancement effects of CeO_(2)

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Journal of Rare Earths 2023年第5期41卷 747-757,I0005页

作者： Yuxin Chen Ning Wang Shengli An Changkun Cai Manyi Xie Xiwen Song School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010China Inner Mongolia Key Laboratory of Advanced Ceramic Materials and Devices Baotou 014010China Key Laboratory of Green Extraction&Efficient Utilization of Light Rare-Earth Resources Ministry of EducationBaotou 014010China

With the deepening understanding for the concept of sustainable development,the utilization of minerals is no longer limited to the traditional way.In this study,an environment friendly method for preparing Fe-Al_(2)O_(3)composites by using natural minerals was investigated.Additionally,the effects of CeO_(2)on the properties of composites were studied.The mechanical properties of Fe-Al_(2)O_(3)composites prepared by natural minerals are affected by the brittleness of glass phase.The strength and toughness of the glass phase in the composite are improved successfully by using rare earth oxides,indicating that the natural rare earths in Bayan Obo minerals have an enhanced influence on the properties of composite materials.The results show that the properties of glass phase can be significantly improved by addition of CeO_(2).At the optimal addition of 3 wt%CeO_(2),the composite achieves the density of 4.21 g/cm^(3),flexural strength of 401 MPa,Vickers hardness of 13.07 GPa and fracture toughness of 6.58 MPa·m^(1/2).The composite has excellent mechanical properties,which can be used in engineering as a cheap structural material.This study aims at reducing waste emissions,improving energy efficiencies and avoiding waste of rare earth resources during the preparation of composite materials.

关键词： Cleaner production Natural minerals Alumina matrix composites Energy saving Rare earth oxides

CeO_(2)nanoparticles-decorated CoP nanocubes for accelerating alkaline electrocatalytic oxygen evolution reaction

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Particuology 2023年第10期81卷 38-44页

作者： Xueda Ding yuxin Huang Dongyang chen Zailai Xie College of Chemistry Fuzhou UniversityFuzhou350116China College of Materials Science and Engineering Fuzhou UniversityFuzhou350116China

Constructing heterojunction interface as an active catalyst is an effective strategy to boost electrocatalytic activity of oxygen evolution reaction(OER).Herein,we report an interfacial CoP/CeO_(2)heterostructure catalyst constructed by interface engineering and selective phosphorization procedure.X-ray photoelectron spectroscopy(XPS)suggests that coupling CeO_(2)nanoparticles on the surface of CoP will generate interfacial interaction at the two-phase interface,resulting in electron transfer between CoP and CeO_(2)components at the interface.Benefitting from the interfacial interaction,large exposed interface area,and luxuriant mesopores structure,CoP/CeO_(2)shows fascinating alkaline OER performance.At the current densities of 10 and 50 mA cm^(−2),the optimal CoP/CeO_(2)heterojunction exhibits lower overpotential(257 and 298 mV)than either CoP(288 and 354 mV)or RuO_(2)(305 and 409 mV).This work provides a facile synthetic protocol for constructing heterostructure interfaces to improve OER performance.

关键词： Prussian blue analogue CeO_(2)nanoparticles CoP/CeO_(2) Oxygen evolution reaction

Cooperative fault detection and recovery in the GNSS positioning of mobile agent swarms based on relative distance measurements

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Chinese Journal of Aeronautics 2022年第5期35卷 129-144页

作者： Qifeng chen Yunhe MENG Song LI yuxin LIAO School of Aeronautics and Astronautics Central South UniversityChangsha 410083China School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China

Relative measurements are exploited to cooperatively detect and recover faults in the positioning of Mobile Agent(MA)Swarms(MASs).First,a network vertex fault detection method based on edge testing is proposed.For each edge,a property that has a functional relationship with the properties of its two vertices is measured and tested.Based on the edge testing results of the network,the maximum likelihood principle is used to identify the vertex fault sources.Second,an edge distance testing method based on the noncentral chi-square distribution is developed for detecting faults in the Global Navigation Satellite System(GNSS)positioning of MASs.Third,a recovery strategy for faults in the positioning of MASs based on distance measurement is provided.The effectiveness of the proposed methods is validated by a simulation case in which an MAS passes through a GNSS spoofing zone.The proposed methods are conducive to increasing the robustness of the positioning of MASs in complex environments.The main novelties include the following:(A)network vertex fault detection is based on concrete probability analysis rather than simple majority voting,and(B)the relation of detectability and recoverability of MAS positioning faults with the structure of the relative measurement network is first disclosed.

关键词： Fault detection and recovery Global Navigation Satellite System Mobile agents Network topology Positioning

Optimal operation of Internet Data Center with PV and energy storage type of UPS clusters

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Global Energy Interconnection 2024年第1期7卷 61-70页

作者： Man chen yuxin Zhao Yuxuan Li Peng Peng Xisheng Tang CSG PGC Energy Storage Research Institute Guangzhou 510000P.R.China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

With the development of green data centers,a large number of Uninterruptible Power Supply(UPS)resources in Internet Data Center(IDC)are becoming idle assets owing to their low utilization rate.The revitalization of these idle UPS resources is an urgent problem that must be addressed.Based on the energy storage type of the UPS(EUPS)and using renewable sources,a solution for IDCs is proposed in this study.Subsequently,an EUPS cluster classification method based on the concept of shared mechanism niche(CSMN)was proposed to effectively solve the EUPS control problem.Accordingly,the classified EUPS aggregation unit was used to determine the optimal operation of the IDC.An IDC cost minimization optimization model was established,and the Quantum Particle Swarm Optimization(QPSO)algorithm was adopted.Finally,the economy and effectiveness of the three-tier optimization framework and model were verified through three case studies.

关键词： Three-tier optimization framework Energy storage type of the UPS EUPS cluster classification method Quantum Particle Swarm Optimization

Kinetic study of CO_(2) fixation into propylene carbonate with water as efficient medium using microreaction system

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Chinese Journal of Chemical Engineering 2022年第10期50卷 247-253页

作者： yuxin Wu Zhuo chen Xiaohui Zhang Jian chen Yundong Wang Jianhong Xu The State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Carbon dioxide(CO_(2))utilization and fixation have become one of the most important research areas nowadays due to the increase of global greenhouse effect.Cyclic carbonate,which is widely used in various fields,can be synthesized by fixation of CO_(2) with epoxide in industry.Moreover,the synthesis of cyclic carbonate is a 100%atom economical reaction,which makes it eco-friendly and promising.To enhance the reaction efficiency and safety,a microreaction system was used as the platform for cycloaddition reaction.In this work,tetrabutylammonium bromide(TBAB)was chosen as catalyst,and propylene oxide(PO)as a mode substrate.Interestingly,the addition of water can increase the propylene carbonate(PC)yield and decrease the activation energy considerably,proving water as catalyst promoter for PC synthesis.PC yield and selectivity could reach 91.6%and 99.8%,respectively.The Influence factors and kinetic equation for CO_(2) cycloaddition were obtained as well.

关键词： Carbon dioxide Microreactor Kinetics Ionic liquids

Spectral purity systems applied for laser-produced plasma extreme ultraviolet lithography sources:a review

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High Power Laser Science and Engineering 2023年第5期11卷 137-152页

作者： Nan Lin Yunyi chen Xin Wei Wenhe Yang yuxin Leng School of Microelectronics Shanghai UniversityShanghaiChina Department of Precision Optics Engineering Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina

With the development of high-volume manufacturing for very-large-scale integrated circuits,the purity of the light source in the extreme ultraviolet lithography(EUVL)system needs to fulfil extreme requirements in order to avoid thermal effect,optical distortion and critical dimension errors caused by out-of-band radiations.This paper reviews the key technologies and developments of the spectral purity systems for both a free-standing system and a built-in system integrated with the collector.The main challenges and developing trends are also discussed,with a view towards practical applications for further improvement.Designing and manufacturing spectral purity systems for EUVL is not a single task;rather,it requires systematic considerations for all relevant modules.Moreover,the requirement of spectral purity filters drives the innovation in filtering technologies,optical micromachining and advanced metrology.

关键词： collector mirror extreme ultraviolet lithography spectral purity filter