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Frontiers of Chemical Science and Engineering 2024年第5期18卷 95-103页

作者： Jianxia Gu Ying Zhu Haiyan Zheng Chunyi Sun Zhongmin Su Department of Chemistry Xinzhou Normal UniversityXinzhou 034000China school of Chemistry Northeast Normal UniversityChangchun 130024China

A novel,cheap and highly efficient Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C nanocomposite has been successfully constructed through simple one-step carbonization method in a nitrogen *** in the precursor can effectively anchor molybdenum-based Keggin-type polyoxometallate and NiCo-layered double hydroxide through electrostatic and coordination interactions,which avoids the aggregation of catalyst particles during the pyrolysis *** optimization,the obtained Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C possesses small size(3-8 nm),large specific surface area and hierarchical pore *** importantly,Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C presents remarkable hydrogen evolution reaction activity with low overpotentials in 0.5 mol·L^(-1)H_(2)SO_(4)(102.3 mV)and 1 mol·L^(-1)KOH(95 mV)to afford the current density of 10 mA·cm^(-2),as well as small Tafel slopes of 82.49 and 99.92 mV·dec^(-1),***,this catalyst also shows outstanding stability for 12 h without a significant change in current *** excellent catalytic performance of Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C can put down to the synergistic effect between multiple components and the small size of the *** work provides unique insights into the preparation of efficient transition metal-based catalysts for HER.

关键词： polyoxometallates layered double hydroxide transition metal-based electrocatalysts hydrogen evolution reaction

A Hybrid Air Quality Prediction Model Based on Empirical Mode Decomposition

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Tsinghua Science and Technology 2024年第1期29卷 99-111页

作者： Yuxuan Cao Difei Zhang Shaoqi Ding Weiyi Zhong Chao Yan school of Computer Science Qufu Normal UniversityRizhao 276826China school of Mathematical Sciences Qufu Normal UniversityQufu 273165China school of Computer Science Qufu Normal UniversityRizhao 270826China College of Economic and Management Shandong University of Science and TechnologyQingdao 250307China

Air pollution is a severe environmental problem in urban *** air quality prediction can help governments and individuals make proper decisions to cope with potential air *** a classic time series forecasting model,the AutoRegressive Integrated Moving Average(ARIMA)has been widely adopted in air quality ***,because of the volatility of air quality and the lack of additional context information,i.e.,the spatial relationships among monitor stations,traditional ARIMA models suffer from unstable prediction *** some deep networks can achieve higher accuracy,a mass of training data,heavy computing,and time cost are *** this paper,we propose a hybrid model to simultaneously predict seven air pollution indicators from multiple monitoring *** proposed model consists of three components:(1)an extended ARIMA to predict matrix series of multiple air quality indicators from several adjacent monitoring stations;(2)the Empirical Mode Decomposition(EMD)to decompose the air quality time series data into multiple smooth sub-series;and(3)the truncated Singular Value Decomposition(SvD)to compress and denoise the expanded *** results on the public dataset show that our proposed model outperforms the state-of-art air quality forecasting models in both accuracy and time cost.

关键词： air quality prediction Empirical Mode Decomposition(EMD) Singular Value Decomposition(SVD) AutoRegressive Integrated Moving Average(ARIMA)

Interpenetrating network-reinforced gel polymer electrolyte for ultra-stable lithium−iodine batteries

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Carbon Energy 2024年第6期6卷 234-247页

作者： Ying Jiang Peng Huang Minman Tong Bingxin Qi Tao Sun Zhongyun Xian Wen Yan Chao Lai school of Chemistry and Materials Science Jiangsu Normal UniversityXuzhouJiangsuChina

Li-I_(2) batteries have attracted much interest due to their high capacity,exceptional rate performance,and low *** so,the problems of unstable Li anode/electrolyte interface and severe polyiodide shuttle in Li-I_(2) batteries need to be ***,the interfacial reactions on the Li anode and I_(2) cathode have been effectively optimized by employing a well-designed gel polymer electrolyte strengthened by cross-linked Ti-O/Si-O(GPETS).The interpenetrating network-reinforced GPETS with high ionic conductivity(1.88×10^(-3)S cm^(-1)at 25℃)and high mechanical strength endows uniform Li deposition/stripping over 1800 h(at 1.0mA cm^(-2),with a plating capacity of 3.0mAh cm^(-2)).Moreover,the GPETS abundant in surface hydroxyls is capable of capturing soluble polyiodides at the interface and accelerating their conversion kinetics,thus synergistically mitigating the shuttle *** from these properties,the use of GPETS results in a high capacity of 207 mAh g^(-1)(1 C)and an ultra-low fading rate of 0.013%per cycle over 2000 cycles(5 C).The current study provides new insights into advanced electrolytes for Li-I_(2) batteries.

关键词： electrode/electrolyte interface gel polymer electrolytes lithium dendrites lithium−iodine batteries polyiodide shuttle

Numerical study on the filtration characteristics of fine particles in granular bed filter at high temperature

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Particuology 2024年第10期93卷 41-53页

作者： Kangning Zhu Jie Cai Yuan Li Xiaoyou Shen Jianfei Xi Yunjun Wang Zhongzhu Gu school of Energy and Mechanical Engineering Nanjing Normal UniversityNanjing210023China

Granular bed filter(GBF)has become one of the current research hot topics due to its excellent performance in removing fine *** this paper,a three-dimensional fixed bed GBF filtration model was established and its accuracy was ***,the GBF filtration performance at high temperature were *** results demonstrate that elevating the temperature diminishes the filtration efficiency,albeit to a limited *** increasing of inlet gas velocity can significantly improve pressure drop for GBF and the filtration efficiency for fine particles of sizes larger than 5μ*** the diameter of stacked granular particle diameter grows,the filtration efficiency and pressure drop *** density of fine particles almost does not affect the filtration efficiency for fine particles of 1∼7μm,but a higher density leads to a higher filtration efficiency for fine particles of sizes bigger than 9μ***,as the fine particles size increases,the change of the filtration efficiency roughly goes through three stages:Stage 1:the filtration efficiency is basically unchanged;Stage 2:the filtration efficiency increases rapidly;Stage 3:the filtration efficiency increases steadily,but the rate of increase slows *** the increase of the fine particles Stokes number,the filtration efficiency of GBF will pass through two phases of stabilization and rapid increase.

关键词： Granular bed filter Fine particles High temperature Filtration efficiency

Input-to-State Stability of Impulsive Switched Systems Involving Uncertain Impulse-Switching Moments

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1515-1517页

作者： Chang Liu Wenlu Liu Tengda Wei Xiaodi Li school of Mathematical and Statistics Shandong Normal UniversityJinan 250014China

Dear Editor,This letter studies the input-to-state stability(ISS)for a class of impulsive switched systems,where uncertain impulse-switching moments are *** robustness of ISS with respect to the perturbations of the occurrence time of impulse-switching moments is revealed by several less conservative dwell-time conditions for the uncertain impulse-switching moments combined with Lyapunov ***,the Lyapunov conditions have multiple coefficients at discrete time so as to handle the hybrid effect of impulse-switching moments,and the case that time derivative of Lyapunov function is indefinite is also taken into ***,a numerical example is proposed to illustrate the effectiveness of the theoretical results.

关键词： letter conservative derivative

Carbon enhanced nucleophilicity of Na_(3)V_(2)(PO_(4))_(3):A general approach for dendrite-free zinc metal anodes

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Journal of Energy Chemistry 2024年第4期91卷 203-212页

作者： Sijun Wang Lingzi Hu Xiaohui Li Dan Qiu Shunhang Qiu Qiancheng Zhou Wenwen Deng Xiaoying Lu Ze Yang Ming Qiu Ying Yu Institute of Nanoscience and Nanotechnology School of Physical Science and TechnologyCentral China Normal UniversityWuhan 430079HubeiChina school of Material Science and Engineering Suzhou University of Science and TechnologySuzhou 215000JiangsuChina Faculty of Science and Technology Technological and Higher Education Institute of Hong KongHong KongChina

Zincophilic property and high electrical conductivity are both very important parameters to design novel Zn anode for aqueous Zn-ion batteries(AZIBs).However,single material is difficult to exhibit zincophilic property and high electrical conductivity at the same ***,originating from theoretical calculation,a zincophilic particle regulation strategy is proposed to address these limitations and carbon coated Na_(3)V_(2)(PO_(4))_(3)is taken as an example to be a protective layer on zinc metal(NVPC@Zn).Na_(3)V_(2)(PO_(4))_(3)(NVP)is a common cathode material for Zn-ion batteries,which is *** materials not only offer an electron pathway to help Zn deposition onto NVPC surface,but also enhance the zinc nucleophilicity of Na_(3)V_(2)(PO_(4))_(3).Hence,this hybrid coating layer can tune zinc deposition and resist side reactions such as hydrogen generation and Zn metal ***,a symmetrical battery with NVPC@Zn electrode displays highly reversible plating/stripping behavior with a long cycle lifespan over 1800 h at2 mA cm^(-2),much better than carbon and Na_(3)V_(2)(PO_(4))_(3)solely modified Zn *** the Na_(3)V_(2)(PO_(4))_(3)is replaced with zincophobic Al2O3or zincophilic V2O3,the stability of the modified zinc anodes is also *** strategy expands the option of zincophilic materials and provides a general and effective way to stabilize the Zn electrode.

关键词： Zinc-ion batteries Zinc anode Carbon enhanced nucleophilicity Zincophilic particle regulation

A New High-Precision and Lightweight Detection Model for Illegal Construction Objects Based on Deep Learning

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Tsinghua Science and Technology 2024年第4期29卷 1002-1022页

作者： Wenjin Liu Lijuan Zhou Shudong Zhang Ning Luo Min Xu school of Cyberspace Security(school of Cryptology) Hainan UniversityHaikou 570228China school of Information Engineering Capital Normal UniversityBeijing 100048China

Illegal construction has caused serious harm around the world. However, current methods are difficult to detect illegal construction activities in time, and the calculation complexity and the parameters of them are large. To solve these challenges, a new and unique detection method is proposed, which detects objects related to illegal buildings in time to discover illegal construction activities. Meanwhile, a new dataset and a high-precision and lightweight detector are proposed. The proposed detector is based on the algorithm You Only Look Once (YOLOv4). The use of DenseNet as the backbone of YDHNet enables better feature transfer and reuse, improves detection accuracy, and reduces computational costs. Meanwhile, depthwise separable convolution is employed to lightweight the neck and head to further reduce computational costs. Furthermore, H-swish is utilized to enhance non-linear feature extraction and improve detection accuracy. Experimental results illustrate that YDHNet realizes a mean average precision of 89.60% on the proposed dataset, which is 3.78% higher than YOLOv4. The computational cost and parameter count of YDHNet are 26.22 GFLOPs and 16.18 MB, respectively. Compared to YOLOv4 and other detectors, YDHNet not only has lower computational costs and higher detection accuracy, but also timely identifies illegal construction objects and automatically detects illegal construction activities.

关键词： object detection lightweight illegal buildings illegal construction objects high-precision

An experimental and theoretical study on photoluminescence of Ce^(3+)-doped ZnS quantum dots and their application in Aspergillus oryzae

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Journal of Rare Earths 2024年第6期42卷 1020-1028,I0001页

作者： Yan Lei Guangzhi Zhang Yitong Yao Gaiqin Zhu Zhong Chen Jiangrong Dan Hua Liu Shuwang Duo school of Materials and Mechanical and Electrical EngineeringJiangxi Science and Technology normal University Nanchang330013China

ZnS and ZnS:3.125%Ce^(3+)(ZSC)quantum dots(QDs)were synthesized by a low-temperature solid-phase *** crystal structure,photoluminescence(PL)properties of ZSC QDs,and their effects on the growth and kojic acid production of Aspergillus oryzae(***)were *** is found that both QDs have a cubic blend structure with the average particle size ranging of 2.75-6.14 ***^(3+)doping not only increases the band gap of ZnS QDs from 3.43 to 3.48 eV,but also increases the PL intensity by about 2.23 times,which is due to the fact that the electron carrier concentration is improved,and then the rate of radiative recombination is *** integral emission intensity,biomass,extracellular proteins yield,and kojic acid production of *** cultured with ZSC(ZnS)QDs are about 4.31(3.23),1.61(1.20),1.12(1.09),and 2.99(1.68)times higher than that of medium without QDs,respectively.

关键词： Zns Quantum dots Doping First-principles calculations Aspergllus oryzae Rare earths

An Approximation Algorithm Based on Seeding Algorithm for Fuzzy k-Means Problem with Penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 387-409页

作者： Wen-Zhao Liu Min Li school of Mathematics and Statistics Shandong Normal UniversityJinan 250014ShandongChina

As a classic NP-hard problem in machine learning and computational geometry,the k-means problem aims to partition the given dataset into k clusters according to the minimal squared Euclidean *** from k-means problem and most of its variants,fuzzy k-means problem belongs to the soft clustering problem,where each given data point has relationship to every center *** to fuzzy k-means problem,fuzzy k-means problem with penalties allows that some data points need not be clustered instead of being paid *** this paper,we propose an O(αk In k)-approximation algorithm based on seeding algorithm for fuzzy k-means problem with penalties,whereαinvolves the ratio of the maximal penalty value to the minimal ***,we implement numerical experiments to show the effectiveness of our algorithm.

关键词： Approximation algorithm Seeding algorithm Fuzzy k-means problem with penalties

Analysis and Design of Time-Delay Impulsive Systems Subject to Actuator Saturation

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 196-204页

作者： Chenhong Zhu Xiuping Han Xiaodi Li IEEE the school of Mathematics and Statistics Shandong Normal UniversityJi'nan 250014China the Center for Control and Engineering Computation Shandong Normal UniversityJi'nan 250014China

This paper investigates the exponential stability and performance analysis of nonlinear time-delay impulsive systems subject to actuator saturation. When continuous dynamics is unstable, under some conditions, it is shown that the system can be stabilized by a class of saturated delayed-impulses regardless of the length of input delays. Conversely, when the system is originally stable, it is shown that under some conditions, the system is robust with respect to sufficient small delayed-impulses. Moreover, the design problem of the controller with the goal of obtaining a maximized estimate of the domain of attraction is formulated via a convex optimization problem. Three examples are provided to demonstrate the validity of the main results.

关键词： Delayed impulses impulsive control impulsive disturbance nonlinear systems saturation