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Fine particle trace elements at a mountain site in southern china:Source identification,transport,and health risks

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Journal of Environmental sciences 2024年第7期141卷 166-181页

作者： Jiaoping Xing Runping Ding Feifeng Chen Linyu Peng Wenhua Wang Xiaoyan Song Qing Ye Yuanqiu Liu Key Laboratory of State Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed School of ForestryJiangxi Agricultural UniversityNanchang 330045China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China College of Geosciences and Engineering North China University of Water Resources&Electric PowerZhengzhou 450046China

Trace elements in atmospheric particulate matter play a significant role in air quality,human health,and biogeochemical *** this study,the trace elements(Ca,Al,K,Fe,Na,Mg,Zn,Pb,Mn,Ti,Cu,Cr,Sr,Ni)in PM2.5samples collected at the summit of *** were analyzed to quantify their abundance,source,transport,and health *** the whole sampling period,the major trace elements was Ca,Al,and *** the trace metals with the lowest concentrations were Sr,Ni,Rb,and *** trace elements were influenced by air mass transport routes,exhibiting an increasing trend of crustal elements in the northwesterly airmass and anthropogenic elements(Zn,Mn,Cu,and Ni)in the easterly air *** dust,coal+biomass burning,vehicle emission,urban nitrate-rich+urban waste incineration emissions,and soil dust+industry emissions were common sources of PM2.5on *** air mass transport routes had various source contribution *** results indicate that trace elements at *** are influenced by regional anthropogenic emissions and monsoon-dominated trace element *** total resulting cancer risk value that these elements posed were below the acceptable risk value of 1×10^(-6),while the non-carcinogenic risk value(1.72)was higher than the safety level,suggesting that non-carcinogenic effects due to these trace elements inhalation were likely to *** emission and coal+biomass burning were the common dominant sources of non-cancer risks posed by trace elements at ***.

关键词： Trace elements Risk assessment Cluster analysis Source apportionment

Nonlinearly induced entanglement in dissipatively coupled optomechanical system

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Chinese Physics B 2024年第6期33卷 255-260页

作者：杨文全冷轩程泂张闻钊 Department of Physics Ningbo UniversityNingbo 315211China

Nonlinearly induced steady-state photon–phonon entanglement of a dissipative coupled system is studied in the bistable regime. Quantum dynamical characteristics are analysed by solving the mean-field and fluctuation equations of the system. It is shown that dissipative coupling can induce bistable behaviour for the effective dissipation of the *** suitable parameters, one of the steady states significantly reduces the dissipative effect of the system. Consequently,a larger steady-state entanglement can be achieved compared to linear dynamics. Furthermore, the experimental feasibility of the parameters is analysed. Our results provide a new perspective for the implementation of steady-state optomechanical entanglement.

关键词： entanglement optomechanical system dissipatively coupling

Research on simulation of gun muzzle flow field empowered by artificial intelligence

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Defence Technology（防务技术） 2024年第2期32卷 196-208页

作者： Mengdi Zhou Linfang Qian Congyong Cao Guangsong Chen Jin Kong Ming-hao Tong School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China Northwest Institute of Mechanical and Electrical Engineering Xianyang712099ShaanxiChina School of Automation Nanjing University of Science and TechnologyNanjing210094China

Artificial intelligence technology is introduced into the simulation of muzzle flow field to improve its simulation efficiency in this paper.A data-physical fusion driven framework is ***,the known flow field data is used to initialize the model parameters,so that the parameters to be trained are close to the optimal *** physical prior knowledge is introduced into the training process so that the prediction results not only meet the known flow field information but also meet the physical conservation *** two examples,it is proved that the model under the fusion driven framework can solve the strongly nonlinear flow field problems,and has stronger generalization and *** proposed model is used to solve a muzzle flow field,and the safety clearance behind the barrel side is *** is pointed out that the shape of the safety clearance under different launch speeds is roughly the same,and the pressure disturbance in the area within 9.2 m behind the muzzle section exceeds the safety threshold,which is a dangerous *** with the CFD results shows that the calculation efficiency of the proposed model is greatly improved under the condition of the same calculation *** proposed model can quickly and accurately simulate the muzzle flow field under various launch conditions.

关键词： Muzzle flow field Artificial intelligence Deep learning Data-physical fusion driven Shock wave

An Innovation of Evaluation and Design of Vehicle Acceleration Sound Based on EEG Signals

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Journal of Bionic Engineering 2024年第1期21卷 344-361页

作者： Liping Xie XinYou Lin Wan Chen Zhien Liu Yawei Zhu College of Mechanical Engineering&Automation Fuzhou UniversityFuzhou 350108China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China

There is a bottleneck in the design of vehicle sound that the subjective perception of sound quality that combines multiple psychological factors fails to be accurately and objectively ***,EEG signals are introduced in this paper to investigate the evaluation and design method of vehicle acceleration sound with powerful sound ***,the experiment of EEG acquisition and subjective evaluation under the stimulation of powerful vehicle sounds is conducted,respectively,then three physiological EEG features of PSD_β,PSD_γand DE are constructed to evaluate the vehicle sounds based on the correlation analysis ***,the Adaptive Genetic Algorithm(AGA)is proposed to optimize the Elman model,where an intelligent model(AGA–Elman)is constructed to objectively predicate the perception of subjects for the vehicle sounds with powerful sound *** results demonstrate that the error of the constructed AGA–Elman model is only 2.88%,which outperforms than the traditional BP and Elman model;Finally,two vehicle acceleration sounds(Design1 and Design2)are designed based on the constructed AGA–Elman model from the perspective of order modulation and frequency modulation,which provide the acoustic theoretical guidance for the design of vehicle sound incorporating the EEG signals.

关键词： EEG signal Brain activity analysis Vehicle sound design Adaptive genetic algorithm-Elman model

A Novel Prescribed-Performance Path-Following Problem for Non-Holonomic Vehicles

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1476-1484页

作者： Zirui Chen Jingchuan Tang Zongyu Zuo Seventh Research Division Beihang University(BUAA)Beijing 100191China IEEE

The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlled *** this context,a novel form of the prescribed performance guiding vector field is introduced,accompanied by a prescribed-time sliding mode con-trol ***,the interdependence among the pre-scribed parameters is *** validate the effectiveness of the proposed method,numerical simulations are presented to demonstrate the efficacy of the approach.

关键词： Guiding vector field non-holonomic vehicle path following prescribed performance sliding mode control

Regulation and application of supramolecular gel with circularly polarized luminescence

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science china Chemistry 2024年第6期67卷 1865-1880页

作者： Shen Song Yulong Shi Liangliang Zhu Bingbing Yue School of Materials and Chemistry&Institute of Bismuth and Rhenium University of Shanghai for Science and TechnologyShanghai200093China State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai200438China

Supermolecular gel is a three-dimensional network structure assembled by small molecules or polymers in solvents through noncovalent *** emergence of system complexity occurs spontaneously during the molecular self-assembly process.A multitude of chiral molecular self-assembly systems have been engineered,facilitating the achievement of circularly polarized luminescence(CPL)through the amalgamation of chiral entities with *** bonding,π-πstacking,and noncovalent forces,such as host-guest interactions and Van der Waals'forces,confer upon supramolecular gels the capacity to react to diverse *** to the flexibility of supramolecular assembly,the CPL properties of supramolecular gels have rich controllability and can be used in various *** this review,we summarized the examples of CPL-active supramolecular gel assembly,and further summarized the assembly environment factors and external ***,the versatility of CPL applications in supramolecular gels is demonstrated,ranging from optical devices,information encryption,biosensing and chemical sensing,and other practical *** conclusion,the study provides insights into the multicultural factors influencing CPL in supramolecular gels,describes their applications in various domains,and presents future perspectives in the field.

关键词： supramolecular gels circularly polarized luminescence self-assembly chirality stimuli-response

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Metal-organic frameworks and their composites for advanced lithium-ion batteries:Synthesis,progress and prospects

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Journal of Energy Chemistry 2024年第2期89卷 449-470,I0011页

作者： Chengcai Liu Borong Wu Tao Liu Yuanxing Zhang Jingwen Cui Lingjun Huang Guoqiang Tan Ling Zhang Yuefeng Su Feng Wu School of Material science and Engineering Beijing Institute of TechnologyBeijing 100081China Chonging Innovation Center Beijing Institute of TechnologyChongqing 401120China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing 100081China

Metal-organic frameworks(MOFs)are among the most promising materials for lithium-ion batteries(LIBs)owing to their high surface area,periodic porosity,adjustable pore size,and controllable chemical *** instance,their unique porous structures promote electrolyte penetration,ions transport,and make them ideal for battery *** the chemical composition of MOF can introduce more active sites for electrochemical ***,MOFs and their related composites have been extensively and thoroughly explored for ***,the reported reviews solely include the applications of MOFs in the electrode materials of LIBs and rarely involve other aspects.A systematic review of the application of MOFs in LIBs is essential for understanding the mechanism of MOFs and better designing related MOFs battery *** review systematically evaluates the latest developments in pristine MOFs and MOF composites for LIB applications,including MOFs as the main materials(anode,cathode,separators,and electrolytes)to auxiliary materials(coating layers and additives for electrodes).Furthermore,the synthesis,modification methods,challenges,and prospects for the application of MOFs in LIBs are discussed.

关键词： Metal-organic frameworks Electrodes Electrolytes Separators Lithium-ion batteries

Interplay between geometric and electronic structures of Pt entities over TiO_(2) for CO oxidation

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science china Chemistry 2024年第2期67卷 705-714页

作者： Xixiong Zhang Wen Shi Shaobo Han Yong Li Wenjie Shen School of Chemistry Dalian University of TechnologyDalian116024China State Key Laboratory of Catalysis Dalian Institution of Chemical PhysicsChinese Academy of SciencesDalian116023China

Monodispersed Pt colloids with a mean size of 2 nm were deposited uniformly on the {110} facets of a rod-shaped rutile TiO_(2),forming a well-defined Pt/TiO_(2) *** treatment of this precursor at elevated temperatures re-dispersed the Pt particles into clusters and ***-calcination at 673 K partially oxidized the Pt particle surface,while calcination at 773 K yielded Pt Oxclusters of 1.6 nm in 7–8 atomic *** calcination at 873 K formed a mixture of raft-like PtO_(x) clusters(1.6 nm,1–2 atomic layers) and cationic *** tested for CO oxidation at 373 K,the Pt particles showed a higher activity than the Pt Oxclusters,whereas the cationic single-atoms were much less *** H_(2)-reduction at 473 K converted the partially oxidized Pt particles into the metallic species,but they were encapsulated by TiO_(2)–xoverlayers because of the strong metal–support interactions,which decreased the activity dramatically.H_(2)-reduction of the PtO_(x) clusters at473 K enhanced the fraction of metallic Pt species without changing the size and geometry,and promoted the activity substantially.H_(2)-treatment of Pt single-atoms at 473 K increased the activity only moderately because most Pt species still kept at cationic *** results straightforwardly differentiated the catalytic behavior of Pt particles,clusters and single-atoms at the same metal loading and over the same TiO_(2) support,and further demonstrated that the electronic structures of Pt entities played a decisive role in the catalytic oxidation,in addition to the specified sizes.

关键词： Pt/TiO_(2)catalyst size effect Pt clusters active sites electronic structures CO oxidation

A Least-squares-based Iterative Method with Better Convergence for PF/OPF in Integrated Transmission and Distribution Networks

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 953-962页

作者： Kunjie Tang Shufeng Dong Yonghua Song College of Electrical Engineering Zhejiang UniversityHangzhou 310027China State Key Laboratory of Internet of Things for Smart City and Department of Electrical and Computer Engineering University of MacaoMacao SARChina IEEE

The limitations of the conventional master-slavesplitting(MSS)method,which is commonly applied to power flow and optimal power flow in integrated transmission and distribution(I-T&D)networks,are first *** that the MSS method suffers from a slow convergence rate or even divergence under some circumstances,a least-squares-based iterative(LSI)method is *** with the MSS method,the LSI method modifies the iterative variables in each iteration by solving a least-squares problem with the information in previous iterations.A practical implementation and a parameter tuning strategy for the LSI method are ***,a LSI-PF method is proposed to solve I-T&D power flow and a LSIheterogeneous decomposition(LSI-HGD)method is proposed to solve optimal power *** experiments demonstrate that the proposed LSI-PF and LSI-HGD methods can achieve the same accuracy as the benchmark ***,these LSI methods,with appropriate settings,significantly enhance the convergence and efficiency of conventional ***,in some cases,where conventional methods diverge,these LSI methods can still converge.

关键词： Fixed-point theory integrated transmission and distribution networks least-squares-based iterative method master-slave-splitting method optimal power flow power flow