检索结果-南通市图书馆

Surface-enhanced Raman Scattering Effect of Ordered Gold Nanoparticle Array for Rhodamine B with Different Morphologies

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2015年第10期33卷 1470-1476页

作者： Xi-hong Zu Zhi-hui Jian 易国斌 Hai-liang Huang ben-bin zhong Hong-sheng Luo Jia-rong Huang Cui Wang School of Chemical Engineering and Light Industry Guangdong University of Technology

In this study, well-ordered gold nanoparticle array on silicon substrate was adopted as an active surface-enhanced Raman scattering substrate for detecting rhodamine B （RB）, and the influence of RB morphologies on surface-enhanced Raman scattering （SERS） properties was discussed. The Au nanoparticle array was prepared by using patterned P4VP nanodomains of poly（styrene-b-4-vinylpyridine）（PS-b-P4VP） diblock copolymer thin films as nanoreactors which is a simple and economical approach. The results show that Raman spectra of RB on the Au nanopaticle array have much stronger intensity than those on the bare silicon substrate by detecting same RB solution. It indicates that the prepared Au nanoparticle array on silicon substrate has a significant Raman enhancement for RB. Interestingly, the Raman intensity of RB from its ethanol solution is much stronger than that from its aqueous solution due to the special morphologies of RB formed in their ethanol solutions. This work provides an effective approach to prepare highly sensitive and stable surface-enhanced Raman scattering substrate.

关键词： Nanoparticle array Rhodamine B Raman spectroscopy Nanowire Nanograss

An Electrochemical Perspective of Aqueous Zinc Metal Anode

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第1期16卷 274-312页

作者： Huibo Yan Songmei Li Jinyan zhong bin Li School of Materials Science and Engineering Beihang UniversityBeijing 100191People’s Republic of China

Based on the attributes of nonflammability,environmental benignity,and cost-effectiveness of aqueous electrolytes,as well as the favorable compatibility of zinc metal with them,aqueous zinc ions batteries(AZIBs)become the leading energy storage candidate to meet the requirements of safety and low cost.Yet,aqueous electrolytes,acting as a double-edged sword,also play a negative role by directly or indirectly causing various parasitic reactions at the zinc anode side.These reactions include hydrogen evolution reaction,passivation,and dendrites,resulting in poor Coulombic efficiency and short lifespan of AZIBs.A comprehensive review of aqueous electrolytes chemistry,zinc chemistry,mechanism and chemistry of parasitic reactions,and their relationship is lacking.Moreover,the understanding of strategies for suppressing parasitic reactions from an electrochemical perspective is not profound enough.In this review,firstly,the chemistry of electrolytes,zinc anodes,and parasitic reactions and their relationship in AZIBs are deeply disclosed.Subsequently,the strategies for suppressing parasitic reactions from the perspective of enhancing the inherent thermodynamic stability of electrolytes and anodes,and lowering the dynamics of parasitic reactions at Zn/electrolyte interfaces are reviewed.Lastly,the perspectives on the future development direction of aqueous electrolytes,zinc anodes,and Zn/electrolyte interfaces are presented.

关键词： Aqueous zinc ions batteries Parasitic reactions Aqueous electrolyte Zinc anode

Visible-frequency nonvolatile reconfigurable Janus metasurfaces for dual-wavelength-switched and spin-asymmetric holograms

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2024年第2期12卷 356-368页

作者： HUAN YUAN ZHEQIANG zhong bin ZHANG College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Big Data Analysis and Fusion Application Technology Engineering Laboratory of Sichuan Province Chengdu 610065China

Janus metasurface holography with asymmetric transmission characteristics provides new degrees of freedom for multiplexing technologies.However,earlier metasurfaces with asymmetrical transmission faced limitations in terms of tunability and multifunctionality.In this study,we propose a metasurface color holographic encryption scheme with dynamic switching and asymmetric transmission at visible frequencies using a low-loss nonvolatile optical phase-change material,Sb_(2)S_(3).Using a modified holographic optimization strategy,we achieved highfidelity asymmetric holographic imaging of a nanostructured metasurface.By controlling the incident direction and wavelength of visible light,as well as the level of crystallization of Sb_(2)S_(3),this reconfigurable metasurface enables the precise manipulation of tunable color holographic image displays.In particular,in the semi-crystalline state of Sb_(2)S_(3),the encoded information can be securely encrypted using a two-channel color-holographic image,whereas only a preset camouflaged image is displayed in the crystalline or amorphous state of Sb_(2)S_(3).The proposed multiencrypted Janus metasurface provides a potential approach for dynamic holographic displays with ultrahigh capacity,holographic encryption,and information storage.

关键词： holographic asymmetric visible

Revisiting aluminum current collector in lithium-ion batteries:Corrosion and countermeasures

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第2期89卷 610-634,I0014页

作者： Shanglin Yang Jinyan zhong Songmei Li bin Li Key Laboratory of Aerospace Advanced Materials and Performance of Ministry of Education School of Materials Science&EngineeringBeihang UniversityBeijing 100191China

With the large-scale service of lithium-ion batteries(LIBs),their failures have attracted significant attentions.While the decay of active materials is the primary cause for LIB failures,the degradation of auxiliary materials,such as current collector corrosion,should not be disregarded.Therefore,it is necessary to conduct a comprehensive review in this field.In this review,from the perspectives of electrochemistry and materials,we systematically summarize the corrosion behavior of aluminum cathode current collector and propose corresponding countermeasures.Firstly,the corrosion type is clarified based on the properties of passivation layers in different organic electrolyte components.Furthermore,a thoroughgoing analysis is presented to examine the impact of various factors on aluminum corrosion,including lithium salts,organic solvents,water impurities,and operating conditions.Subsequently,strategies for electrolyte and protection layer employed to suppress corrosion are discussed in detail.Lastly and most importantly,we provide insights and recommendations to prevent corrosion of current collectors,facilitate the development of advanced current collectors and the implementation of next-generation high-voltage stable LIBs.

关键词： Lithium-ion battery Aluminum current collector Corrosion Electrochemical performance Electrolyte Protective layer

A Lightweight Network with Dual Encoder and Cross Feature Fusion for Cement Pavement Crack Detection

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第7期140卷 255-273页

作者： zhong Qu Guoqing Mu bin Yuan School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing400065China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

Automatic crack detection of cement pavement chiefly benefits from the rapid development of deep learning,with convolutional neural networks(CNN)playing an important role in this field.However,as the performance of crack detection in cement pavement improves,the depth and width of the network structure are significantly increased,which necessitates more computing power and storage space.This limitation hampers the practical implementation of crack detection models on various platforms,particularly portable devices like small mobile devices.To solve these problems,we propose a dual-encoder-based network architecture that focuses on extracting more comprehensive fracture feature information and combines cross-fusion modules and coordinated attention mechanisms formore efficient feature fusion.Firstly,we use small channel convolution to construct shallow feature extractionmodule(SFEM)to extract low-level feature information of cracks in cement pavement images,in order to obtainmore information about cracks in the shallowfeatures of images.In addition,we construct large kernel atrous convolution(LKAC)to enhance crack information,which incorporates coordination attention mechanism for non-crack information filtering,and large kernel atrous convolution with different cores,using different receptive fields to extract more detailed edge and context information.Finally,the three-stage feature map outputs from the shallow feature extraction module is cross-fused with the two-stage feature map outputs from the large kernel atrous convolution module,and the shallow feature and detailed edge feature are fully fused to obtain the final crack prediction map.We evaluate our method on three public crack datasets:DeepCrack,CFD,and Crack500.Experimental results on theDeepCrack dataset demonstrate the effectiveness of our proposed method compared to state-of-the-art crack detection methods,which achieves Precision(P)87.2%,Recall(R)87.7%,and F-score(F1)87.4%.Thanks to our lightweight crack detectionmodel,the parameter count of the mo

关键词： Shallow feature extraction module large kernel atrous convolution dual encoder lightweight network crack detection

Mg-doped,carbon-coated,and prelithiated SiO_(x) as anode materials with improved initial Coulombic efficiency for lithium-ion batteries

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Carbon Energy 2024年第3期6卷 204-214页

作者： bin Liu Jie Liu Cheng zhong Wenbin Hu Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) School of Materials Science and EngineeringTianjin UniversityTianjinChina Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjinChina Joint School of National University of Singapore and Tianjin University TianjinChina International Campus of Tianjin University Binhai New CityFuzhouChina

Silicon suboxide(SiO_(x),x≈1)is promising in serving as an anode material for lithium-ion batteries with high capacity,but it has a low initial Coulombic efficiency(ICE)due to the irreversible formation of lithium silicates during the first cycle.In this work,we modify SiO_(x) by solid-phase Mg doping reaction using low-cost Mg powder as a reducing agent.We show that Mg reduces SiO_(2) in SiO_(x) to Si and forms MgSiO_(3) or Mg_(2)SiO_(4).The MgSiO_(3) or Mg_(2)SiO_(4) are mainly distributed on the surface of SiO_(x),which suppresses the irreversible lithium-ion loss and enhances the ICE of SiO_(x).However,the formation of MgSiO_(3) or Mg_(2)SiO_(4) also sacrifices the capacity of SiO_(x).Therefore,by controlling the reaction process between Mg and SiO_(x),we can tune the phase composition,proportion,and morphology of the Mg-doped SiO_(x) and manipulate the performance.We obtain samples with a capacity of 1226 mAh g^(–1) and an ICE of 84.12%,which show significant improvement over carbon-coated SiO_(x) without Mg doping.By the synergistical modification of both Mg doping and prelithiation,the capacity of SiO_(x) is further increased to 1477 mAh g^(–1) with a minimal compromise in the ICE(83.77%).

关键词： initial Coulombic efficiency lithium-ion batteries magnesium doping prelithiation silicon suboxide

Preparing lipid nanoparticles with tunable drug loading capacity and morphology via improved sequential nanoprecipitation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第5期67卷 1373-1374页

作者： Haoran Wang ben zhong Tang Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction Department of Chemistry.Institute of Molecular Functional MaterialsState Key Laboratory of NeuroscienceDivision of Biomedical Engineering and Division of Life ScienceThe Hong Kong University of Science and TechnologyHong Kong 999077China School of Science and Engineering Shenzhen Institute of Aggregate Science and Technology The Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Shenzhen 518172China

Nanotechnology hailed as a revolutionary new technology of the 21st century, has ignited a wave of innovation across diverse fields spanning chemistry, physics, materials science,medicine, engineering, and electronics. In 2016, Nature published an article titled “The nanolight revolution is coming”, underscoring that “virus-sized particles that emit light in every color could transform applications ranging from television displays to cancer treatment”.

关键词： sized loading treatment

Hybrid Network Model Based on Data Enhancement for Short-term Power Prediction of New PV Plants

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 77-88页

作者： Shangpeng zhong Xiaoming Wang bin Xu Hongbin Wu Ming Ding the Anhui Province Key Laboratory of Renewable Energy Utilization and Energy Saving Hefei University of TechnologyHefei 230009China the State Grid Anhui Electric Power Research Institute Hefei 230061China

This study proposes a hybrid network model based on data enhancement to address the problem of low accuracy in photovoltaic(PV)power prediction that arises due to insuffi cient data samples for new PV plants.First,a time-series gener ative adversarial network(TimeGAN)is used to learn the distri bution law of the original PV data samples and the temporal correlations between their features,and these are then used to generate new samples to enhance the training set.Subsequently,a hybrid network model that fuses bi-directional long-short term memory(BiLSTM)network with attention mechanism(AM)in the framework of deep&cross network(DCN)is con structed to effectively extract deep information from the origi nal features while enhancing the impact of important informa tion on the prediction results.Finally,the hyperparameters in the hybrid network model are optimized using the whale optimi zation algorithm(WOA),which prevents the network model from falling into a local optimum and gives the best prediction results.The simulation results show that after data enhance ment by TimeGAN,the hybrid prediction model proposed in this paper can effectively improve the accuracy of short-term PV power prediction and has wide applicability.

关键词： New photovoltaic(PV)plant short-term predic tion time-series generative adversarial network(TimeGAN) hy brid network hyperparameter

Resource Allocation in Multi-User Cellular Networks:A Transformer-Based Deep Reinforcement Learning Approach

在线全文

学校读者我要写书评

暂无评论

China Communications 2024年第5期21卷 77-96页

作者： Zhao Di Zheng zhong Qin Pengfei Qin Hao Song bin State Key Laboratory of Integrated Services Networks Xidian University710071China China Academy of Space Technology Beijing 100081China

To meet the communication services with diverse requirements,dynamic resource allocation has shown increasing importance.In this paper,we consider the multi-slot and multi-user resource allocation(MSMU-RA)in a downlink cellular scenario with the aim of maximizing system spectral efficiency while guaranteeing user fairness.We first model the MSMURA problem as a dual-sequence decision-making process,and then solve it by a novel Transformerbased deep reinforcement learning(TDRL)approach.Specifically,the proposed TDRL approach can be achieved based on two aspects:1)To adapt to the dynamic wireless environment,the proximal policy optimization(PPO)algorithm is used to optimize the multi-slot RA strategy.2)To avoid co-channel interference,the Transformer-based PPO algorithm is presented to obtain the optimal multi-user RA scheme by exploring the mapping between user sequence and resource sequence.Experimental results show that:i)the proposed approach outperforms both the traditional and DRL methods in spectral efficiency and user fairness,ii)the proposed algorithm is superior to DRL approaches in terms of convergence speed and generalization performance.

关键词： dynamic resource allocation multi-user cellular network spectrum efficiency user fairness