检索结果-南通市图书馆

Chinese Journal of Chemical Engineering 2024年第3期67卷 58-67页

作者： Deqing He Zihao Xie Qian Yang wei Wang Chao su School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212100China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

The sluggish redox kinetics of polysulfides in lithium-sulfur(Li-S)batteries are a significant obstacle to their widespread adoption as energy storage ***,recent studies have shown that tungsten oxide(WO_(3))can facilitate the conversion kinetics of polysulfides in Li-S ***,we fabricated host materials for sulfur using nitrogen-doped carbon nanotubes(N-CNTs)and WO_(3).We used low-cost components and simple procedures to overcome the poor electrical conductivity that is a disadvantage of metal *** composites of WO_(3) and N-CNTs(WO_(3)/N-CNTs)create a stable framework structure,fast ion diffusion channels,and a 3D electron transport network during electrochemical reaction *** a result,the WO_(3)/N-CNT-Li2S6 cathode demonstrates high initial capacity(1162 mA·h·g^(-1) at 0.5℃),excellent rate performance(618 mA·h·g^(-1) at 5.5℃),and a low capacity decay rate(0.093%up to 600 cycles at 2℃).This work presents a novel approach for preparing tungsten oxide/carbon composite catalysts that facilitate the redox kinetics of polysulfide conversion.

关键词： Li-S batteries Composites Ion diffusion channels 3D electron transport network Redox kinetics

Evolutionary mechanism and frequency response of graphite electrode at extreme temperatures

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 7283-7289页

作者： Shanpeng Pei Zhiyong Zhang Xiuli Zhang Yan Liu xiang Han Linshan Luo Pengfei su Chaofei Lan wei Huang Ziqi Zhang Ming-Sheng Wang Songyan Chen Department of Physics Xiamen UniversityXiamen 361005China Shandong Electric Power Engineering Consulting Institute Corporation Jinan 250031China State Key Lab of Physical Chemistry of Solid surfaces College of MaterialsXiamen UniversityXiamen 361005China School of Semiconductor Science and Technology South China Normal UniversityFoshan 528225China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037China National Key Laboratory of Integrated Circuits and Microsystems Chongqing 400000China

The battery management system is employed to monitor the external temperature of the lithium-ion battery in order to detect any potential ***,this outside–in detection method often suffers from a lag and is therefore unable to accurately predict the battery’s real-time ***,an inside–out frequency response approach is used to accurately monitor the battery’s state at various temperatures in real-time and correlate it with the solid electrolyte interphase(SEI)evolution of the graphite *** SEI evolution at temperatures of−15,25,60,and 90℃exhibits certain regular characteristics with temperature *** a temperature of−15℃,the Li^(+)-solvent interaction of lithium-ion slowed down,resulting in a significant reduction in *** 25℃,a LiF-rich inorganic SEI was identified as forming,which facilitated lithium-ion ***,high temperatures would induce decomposition of lithium hexafluorophosphate(LiPF_(6))and lithium-ion *** the extreme temperature of 90℃,the SEI would be organic-rich,and Li_(x)P_(y)F_(z),a decomposition product of lithium salts,was further oxidized to Li_(x)PO_(y)F_(z),which led to a surge in the charge-transfer resistance at SEI(R_(sei))and a reduction in Coulombic efficiency(CE).This changing relationship can be recorded in real time from the inside out by electrochemical impedance spectroscopy(EIS)*** provides a new theoretical basis for the structural evolution of lithium-ion batteries and the regular characterization of EIS.

关键词： graphite electrode solid electrolyte interphase(SEI)film extreme temperatures frequency response evolutionary mechanism

Cu nanowire array with designed interphases enabling high performance Si anode toward flexible lithium-ion battery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 1516-1524页

作者： Pengfei su Ziqi Zhang Linshan Luo Zhiyong Zhang Chaofei Lan Yahui Li Shaowen Xu Shanpeng Pei Guangyang Lin Cheng Li xiang Han wei Huang Songyan Chen Fujian Provincial Key Laboratory of Semiconductors and Applications Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient DevicesDepartment of PhysicsXiamen UniversityXiamen 361005China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037China Science and Technology on Analog Integrated Circuit Laboratory Chongqing 400060China Shandong Electric Power Engineering Consulting Institute Co. Ltd.Jinan 250013China

To meet the growing demand for wearable smart electronic devices,the development of flexible lithium-ion batteries(LIBs)is *** is an ideal candidate for the anode material of flexible lithium-ion batteries due to its high specific capacity,low working potential,and earth *** largest challenge in developing a flexible silicon anode is how to maintain structural integrity and ensure stable electrochemical reactions during external *** this work,we propose a novel design for fabricating core–shell electrodes based on a copper nanowire(CuNW)array core and magnetron sputtered Si/C *** nanowire array structure has characteristics of bending under longitudinal stress and twisting under transverse stress,which helps to maintain the mechanical stability of the structure during electrode bending and *** low-temperature annealing generates a small amount of Cu3Si alloy,which enhances the connection strength between Si and the conductive network and solves the poor conductivity problem of Si,which is known as a semiconductor *** unique configuration design of CuNW@Si@C-400℃ leads to stable long cycle performance of 1109 mAh∙g^(-1) after 1000 cycles and excellent rate performance of 500 mAh∙g^(-1) at a current density of 10 A∙g^(-1).Furthermore,the CuNW@Si@C-400℃||LiFePO_(4)(LFP)full battery demonstrates excellent flexibility,with a capacity retention of more than 96%after 100 *** study provides a promising strategy for the development of flexible lithium-ion batteries.

关键词： flexible lithium-ion battery silicon anode magnetron sputtering core–shell electrode Cu nanowire array

Effect of pipe installation and external load on buried steel pipe responses:Experimental and numerical investigations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Underground Space 2024年第2期15卷 44-58页

作者： Yadong Zhang Ron Chik-Kwong Wong Jianfeng Chen wei su Department of Civil Engineering Schulich School of EngineeringUniversity of CalgaryCalgaryAB T2N 1N4Canada Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

During pipe installation,compacting soil at pipe sides causes an initial pipe deformation which is known as the"peaking"***,in conventional pipe design codes,only pipe deformation caused by vertical overburden is considered while the"peaking"effect is *** this study,a full-scale test was conducted on a Grade X52 steel pipe with a diameter of 600 mm to investigate the impacts of both soil compaction and vertical overburden on pipe *** compaction and external load were found to elongate and shorten the vertical pipe diameter,***"peaking"effect was observed during the installation procedure accompanied by the highest pipe stress measured at the pipe ***,a two-dimensional finite element model was created and validated based on the calculated pipe stresses from the experimental study.A parametric study was performed thereafter to numerically study the impacts of soil water content,pipe wall thickness,compaction pressure,and lift thickness on pipe responses due to soil compaction and external *** increase in the"peaking"effect is observed with increasing soil water content and compaction pressure,while an increase in pipe wall thickness or lift thickness would cause a decrease in the"peaking"effect.

关键词： X52 steel Soil compaction External load Peaking effect Pipe deflection Soil arching

Data-Driven Modeling of Partially Observed Biological Systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications on Applied Mathematics and Computation 2024年第1期6卷 739-754页

作者： wei-Hung su Ching-Shan Chou Dongbin Xiu Department of Mathematics The Ohio State UniversityColumbusOH43221USA

We present a numerical approach for modeling unknown dynamical systems using partially observed data,with a focus on biological systems with(relatively)complex dynamical *** an extension of the recently developed deep neural network(DNN)learning methods,our approach is particularly suitable for practical situations when(i)measurement data are available for only a subset of the state variables,and(ii)the system parameters cannot be observed or measured at *** demonstrate that,with a properly designed DNN structure with memory terms,effective DNN models can be learned from such partially observed data containing hidden *** learned DNN model serves as an accurate predictive tool for system *** a few representative biological problems,we demonstrate that such DNN models can capture qualitative dynamical behavior changes in the system,such as bifurcations,even when the parameters controlling such behavior changes are completely unknown throughout not only the model learning process but also the system prediction *** learned DNN model effectively creates a“closed”model involving only the observables when such a closed-form model does not exist mathematically.

关键词： Deep neural network(DNN) Governing equation discovery Biological system Partial observation

Experimental Study on the Electrochemical Performance of PEMFC under Different Assembly Forces

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2024年第3期37卷 265-274页

作者： Tongze su Jiaran Liu Yanqiang wei Yihuizi Li weichao Luo Jinzhu Tan Nanjing Tech University Nanjing 211816China

Proton exchange membrane fuel cell(PEMFC)is of paramount significance to the development of clean *** components of PEMFC are assembled using many pairs of nuts and *** assembly champing bolt torque is critical to the electrochemical performance and mechanical stability of *** this paper,a PEMFC with the threechannel serpentine flow field was used and *** different assembly clamping bolt torques were applied to the PEMFC in three uniform assembly bolt torque and six non-uniform assembly bolt torque conditions,*** then,the electrochemical performance experiments were performed to study the effect of the assembly bolt torque on the electrochemical *** test results show that the assembly bolt torque significantly affected the electrochemical performance of the *** uniform assembly bolt torque conditions,the maximal power density increased initially as the assembly bolt torque increased,and then decreased on further increasing the assembly *** existed the optimum assembly torque which was found to be 3.0 N·m in this *** non-uniform assembly clamping bolt torque conditions,the optimum electrochemical performance appeared in the condition where the assembly torque of each bolt was closer to be 3.0 N·*** could be due to the change of the contact resistance between the gas diffusion layer and bipolar plate and mass transport resistance for the hydrogen and oxygen towards the catalyst *** work could optimize the assembly force conditions and provide useful information for the practical PEMFC stack assembly.

关键词： Proton exchange membrane fuel cell Assembly force Experiment Electrochemical performance

Transfer matrix method for free and forced vibrations of multi-level functionally graded material stepped beams with different boundary conditions

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 983-1000页

作者： Xiaoyang su Tong HU wei ZHANG Houjun KANG Yunyue CONG Quan YUAN School of Civil Engineering and Architecture Guangxi UniversityNanning 530004China Scientific Research Center of Engineering Mechanics Guangxi UniversityNanning 530004China State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures Guangxi UniversityNanning 530004China

Functionally graded materials(FGMs)are a novel class of composite materials that have attracted significant attention in the field of engineering due to their unique mechanical *** study aims to explore the dynamic behaviors of an FGM stepped beam with different boundary conditions based on an efficient solving *** the assumptions of the Euler-Bernoulli beam theory,the governing differential equations of an individual FGM beam are derived with Hamilton’s principle and decoupled via the separation-of-variable ***,the free and forced vibrations of the FGM stepped beam are solved with the transfer matrix method(TMM).Two models,i.e.,a three-level FGM stepped beam and a five-level FGM stepped beam,are considered,and their natural frequencies and mode shapes are *** demonstrate the validity of the method in this paper,the simulation results by ABAQUS are also *** this basis,the detailed parametric analyses on the frequencies and dynamic responses of the three-level FGM stepped beam are carried *** results show the accuracy and efficiency of the TMM.

关键词： transfer matrix method(TMM) free vibration forced vibration functionally graded material(FGM) stepped beam

Unraveling the hydraulic properties of loess for landslide prediction:A study on variations in loess landslides in Lanzhou,Dingxi,and Tianshui,China

在线全文

学校读者我要写书评

暂无评论

China Geology 2024年第2期7卷 291-302页

作者： Gao-chao Lin wei Liu Xing su School of Civil and Environmental Engineering University of New South WalesSydneyNSW 2052Australia Institute of Transportation Inner Mongolia UniversityHohhot 010070China Institute of Geological Hazards Prevention Gansu Academy of SciencesLanzhou 730000China

Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re *** involvement of water repre sents a critical factor in inducing loess *** study focuses on three neighboring cities sequentially situated on the Loess Plateau along the direction of aeolian deposition of loess,namely Lanzhou,Dingxi,and Tianshui,which are densely populated and prone to landslide *** variations in hydraulic properties,including water retention capacity and permeability,are investigated through Soil Water Characteristic Curve(SWCC)test and hydraulic conductivity *** experimental findings revealed that Tianshui loess exhibited the highest water retention capacity,followed by Dingxi loess,while Lanzhou loess demonstrated the lowest water retention ***,the results for the saturated permeability coefficient were found to be the opposite:Tianshui loess showed the lowest permeability,whereas Lanzhou loess displayed the highest *** results are supported and analyzed by scanning electron microscopy(SEM)*** addition,the water retention capacity is mathematically expressed using the van Genuchten model and extended to predict unsaturated hydraulic properties of *** experimental results exhibit a strong accordance with one another and align with the regional distribution patterns of disasters.

关键词： Loess Landslide Hydraulic properties Water retention capacity and permeability Soil Water Characteristic Curve(SWCC) Hydraulic conductivity Van Genuchten model Hydrogeological engineering Geological hazards prevention engineering

Abnormal Traffic Detection for Internet of Things Based on an Improved Residual Network

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第6期79卷 4433-4448页

作者： Tingting su Jia Wang wei Hu Gaoqiang Dong Jeon Gwanggil School of Computer Science and Technology Xinjiang UniversityUrumqi830046China School of Cyber Science and Engineering Jinling Institute of Technology CityNanjing210000China College of Information Technology Incheon National UniversityIncheon22012Korea

Along with the progression of Internet of Things(IoT)technology,network terminals are becoming continuously more *** has been widely applied in various scenarios,including urban infrastructure,transportation,industry,personal life,and other socio-economic *** introduction of deep learning has brought new security challenges,like an increment in abnormal traffic,which threatens network *** feature extraction leads to less accurate classification *** abnormal traffic detection,the data of network traffic is high-dimensional and *** data not only increases the computational burden of model training but also makes information extraction more *** address these issues,this paper proposes an MD-MRD-ResNeXt model for abnormal network traffic *** fully utilize the multi-scale information in network traffic,a Multi-scale Dilated feature extraction(MD)block is *** module can effectively understand and process information at various scales and uses dilated convolution technology to significantly broaden the model’s receptive *** proposed Max-feature-map Residual with Dual-channel pooling(MRD)block integrates the maximum feature map with the residual *** module ensures the model focuses on key information,thereby optimizing computational efficiency and reducing unnecessary information *** results show that compared to the latest methods,the proposed abnormal traffic detection model improves accuracy by about 2%.

关键词： Abnormal network traffic deep learning residual network multi-scale feature extraction max-feature-map

Single-cluster electronics using metallic clusters:Fabrications,regulations,and applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第1期17卷 65-78页

作者： Caiyun wei wei Xu Shurui Ji Ruiyun Huang Junyang Liu Wenqiu su Jie Bai Jiale Huang Wenjing Hong State Key Laboratory of Physical Chemistry of Solid surfaces National Engineering Research Centre of Chemicals for Electronic ManufacturingCollege of Chemistry and Chemical Engineering&Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM)Xiamen UniversityXiamen 361005China

Metallic clusters,ranging from 1 to 2 nm in size,have emerged as promising candidates for creating nanoelectronic devices at the single-cluster *** the intermediate quantum properties between metals and semiconductors,these metallic clusters offer an alternative pathway to silicon-based electronics and organic molecules for miniaturized electronics with dimensions below 5 *** progress has been made in studies of single-cluster electronic ***,a clear guide for selecting,synthesizing,and fabricating functional single-cluster electronic devices is still *** review article provides a comprehensive overview of single-cluster electronic devices,including the mechanisms of electron transport,the fabrication of devices,and the regulations of electron transport ***,we discuss the challenges and future directions for single-cluster electronic devices and their potential applications.

关键词： single-cluster junctions electronic properties electron transport metallic clusters structure regulation