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Cu_(2)Se@C thin film with three-dimensional braided structure as a cathode material for enhanced Cu^(2+) storage

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Chinese Chemical Letters 2024年第5期35卷 523-528页

作者： Wenhao Chen Muxuan wu Han Chen Lue Mo yirong Zhu College of Materials and Advanced Manufacturing Hunan University of TechnologyZhuzhou 412007China Hunan Key of Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha 410022China

In the face of multiple challenges brought by the changes of global climate and environment,developing clean energy and updating green energy storage equipment are important ways to achieve carbon peak and carbon *** batteries have become a research hotspot due to their advantages of using the multivalent charge carrier,high ionic conductivity,environmental friendliness and cost *** this work,the Cu_(2)Se@C(Cu_(2)Se coated on carbon clothes)thin film with a three-dimensional braided structure is fabricated by a simple electrochemical deposition method for Cu^(2+)storage for the first *** with the commercial Cu_(2)Se powder,the well-designed Cu_(2)Se@C film shows enhanced specific capacity(640 mAh/g at 0.5 A/g)and rate performance(542 mAh/g at 5 A/g)as well as superior cycling stability(82.7%capacity retention after 1000 cycles at 1 A/g).The Cu^(2+)storage mechanism of the Cu_(2)Se@C electrode is based on a reversible phase transition process of Cu_(2)Se←→Cu_(2-x)Se←→CuSe←→CuSe_(2).In kinetic characteristic analysis,the Cu_(2)Se@C electrode demonstrates faster Cu^(2+)diffusion in discharge process than charge process resulting from the phase transition and the variation of interplanar *** work highlights a facile one-piece design strategy and opens a new gateway for the exploration of advanced aqueous energy storage systems.

关键词： Cu_(2)Se@C Cu^(2+)storage Conversion mechanism Kinetic characteristic Flexible energy storage

维普期刊数据库

Analysis of phase preservation and interferometric offset test in sparse SAR imaging

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Science China(Information Sciences) 2024年第2期67卷 219-231页

作者： Zhongqiu XU Bingchen ZHANG Guangzuo LI Xueli ZHAN Yanfei BAO yirong wu Key Laboratory of Spatial Information Processing and Application System Technology Chinese Academy of Sciences Aerospace Information Research Institute Chinese Academy of Sciences School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of Sciences PLA Academy of Military Sciences

Sparse synthetic aperture radar(SAR) imaging has emerged as a reliable microwave imaging scheme in the recent decade and excels in down-sampling reconstruction and full-sampling performance improvements such as noise, sidelobe, speckle, and ambiguity suppression. To utilize complex image products of sparse reconstruction for improvement in polarimetric, interferometric, and tomographic SAR imaging, it is necessary to evaluate the phase preservation of sparse SAR imaging. In this study, we first introduce the general alternating direction method of multipliers(ADMM) as the universal framework for sparse reconstruction algorithms and adopt chirp scaling algorithm(CSA)-based azimuth-range decouple operators to avoid expensive data storage and processing. Further, we theoretically analyze the phase preservation of the sparse reconstruction algorithm through a comparison with the reconstruction results of CSA. Finally,we conduct the interferometric offset test on the sparse reconstruction results of simulated and real Gaofen-3(GF-3) SAR data, demonstrating the phase-preserving ability of sparse methods.

关键词： sparse SAR imaging phase preservation interferometric offset test general ADMM azimuth-range decouple

Studies on MB-SAR 3D imaging algorithm using Yule-Walker method

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Science China(Information Sciences) 2010年第9期53卷 1848-1859页

作者： WANG Bin1,2*,WANG YanPing1,HONG Wen1,TAN WeiXian1,2 & wu yirong1 1National Key Laboratory of Microwave Imaging Technology,Institute of Electronics,Chinese Academy of Sciences,Beijing 100190,China 2Graduate University of Chinese Academy of Sciences,Beijing 100049,China National Key Laboratory of Microwave Imaging Technology Institute of Electronics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Multibaseline synthetic aperture radar(MB-SAR) can form a synthetic aperture in the height direction with multiple parallel observations,so it has the resolving capability in the height direction and can realize three-dimensional(3D) imaging for the *** analytic model of MB-SAR based on spectrum estimation is analyzed in this *** on the more general geometric model,we derive the signal model for MB-SAR 3D *** then Yule-Walker algorithm is proposed to realize MB-SAR 3D imaging meanwhile the principle is analyzed and the steps of Yule-Walker algorithm are *** algorithm can get the 3D image of the target with high resolution using fewer ***,the experimental results of MB-SAR 3D imaging using Yule-Walker algorithm are presented,which are generated with the simulated data and the data collected in anechoic chamber.

关键词： MB-SAR 3D SAR imaging algorithm SAR spectrum estimation Yule-Walker method

Maximal effective baseline for polarimetric interferometric SAR forest height estimation

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Science China(Information Sciences) 2012年第4期55卷 867-876页

作者： ZHOU YongSheng 1,2,3,HONG Wen 1,2,WANG YanPing 1,2 & wu yirong 1,2 1 National Key Laboratory of Science &Technology on Microwave Imaging,Beijing 100190,China 2 Institute of Electronics,Chinese Academy of Sciences,Beijing 100190,China 3 Academy of Opto-Electronics,Chinese Academy of Sciences,Beijing 100094,China National Key Laboratory of Science & Technology on Microwave Imaging Beijing China Institute of Electronics Chinese Academy of Sciences Beijing China Academy of Opto-Electronics Chinese Academy of Sciences Beijing China

The concepts of critical baseline and maximal effective baseline have been defined for interferometric SAR (InSAR) DEM application based on the spatial decorrelation (which is a function of baseline).This paper puts forward these two concepts to polarimetric interferometric SAR (Pol-InSAR) forest height estimation *** application makes use of volume decorrelation,which is also a function of *** both the spatial decorrelation and volume decorrelation are considered to determine Pol-InSAR critical and maximal effective *** various decorrelation effects are *** the calculation formula of Pol-InSAR maximal effective baseline are presented and compared to that of *** validation,RVoG-based and PolSARpro-based simulation data and DLR ESAR data are *** concept of Pol-InSAR maximal effective baseline is of practical significance in selection of Pol-InSAR image pairs as well as in the design of further Pol-InSAR systems.

关键词： Pol-InSAR maximal baseline forest height estimation

Influence factors of sparse microwave imaging radar system performance:approaches to waveform design and platform motion analysis

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Science China(Information Sciences) 2012年第10期55卷 2301-2317页

作者： ZHANG Zhe 1,2,3,ZHANG BingChen 1,2,JIANG ChengLong 1,2,3,XIANG Yin 1,2,HONG Wen 1,2 & wu yirong 1,2 1 Science and Technology on Microwave Imaging Laboratory,Beijing 100190,China 2 Institute of Electronics,Chinese Academy of Sciences,Beijing 100190,China 3 Graduate University,Chinese Academy of Sciences,Beijing 100190,China Science and Technology on Microwave Imaging Laboratory Beijing China Institute of Electronics Chinese Academy of Sciences Beijing China Graduate University Chinese Academy of Sciences Beijing China

Sparse microwave imaging radar is a newly developed concept of microwave imaging system,which tries to combine the traditional radar imaging system with sparse signal processing theories,achieving the aim of reducing the complexity of microwave imaging systems and enhancing the system *** this paper,we introduce some basic concepts of sparse signal processing theory,and then apply it to the traditional radar imaging system to get the mathematical model of sparse microwave imaging *** analyze the factors that determine the performance of sparse microwave imaging radar,including scene,waveform and *** to the radar model,we analyze how these factors influence the radar system and how to optimize *** results of the sparse microwave imaging radar system are also provided.

关键词： sparse microwave imaging radar synthetic aperture radar compressive sensing Lq regularization waveform design

Synthetic aperture radar tomography sampling criteria and three-dimensional range migration algorithm with elevation digital spotlighting

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Science in China(Series F) 2009年第1期52卷 100-114页

作者： TAN WeiXian1,2,3?, HONG Wen1,2, WANG YanPing1,2, LIN Yun1,2,3 & wu yirong1,2 1 State Key Laboratory of Microwave Imaging Technology, Beijing 100190, China 2 Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China 3 Graduate School, Chinese Academy of Sciences, Beijing 100190, China State Key Laboratory of Microwave Imaging Technology Institute of Electronics Chinese Academy of Sciences Graduate School Chinese Academy of Sciences

Based on the general geometric model of multi-baseline Synthetic Aperture Radar Tomography （TomoSAR）, the three-dimensional （3-D） sampling criteria, the analytic expression of the 3-D Point Spread Function （PSF） and the 3-D resolution are derived in the 3-D wavenumber domain in this paper. Considering the relationship between the observation geometry and the size of illuminated scenario, a 3-D Range Migration Algorithm with Elevation Digital Spotlighting （RMA-EDS） is proposed. With this algorithm 3-D images of the area of interest can be directly and accurately reconstructed in the 3-D space avoiding the complex operations of 3-D geometric correction. Finally, theoretical analyses and simulation results are presented to demonstrate the shift-varying property of the 3-D PSF and the spatialvarying property of the 3-D resolution and to demonstrate the validity of the 3-D RMA-EDS.

关键词： synthetic aperture radar tomography (TomoSAR) three-dimensional (3-D) SAR imaging 3-D sampling criteria 3-D resolution,3-D range migration algorithm with elevation digital spotlighting (RMA-EDS)

维普期刊数据库

Multi-channel SAR imaging based on distributed compressive sensing

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Science China(Information Sciences) 2012年第2期55卷 245-259页

作者： LIN YueGuan1,2,3,ZHANG BingChen1,2,JIANG Hai1,2,3,HONG Wen1,2 & wu yirong1,2 1National Key Laboratory of Science and Technology on Microwave Imaging,Beijing 100190,China 2Institute of Electronics,Chinese Academy of Sciences,Beijing 100190,China 3Graduate University of Chinese Academy of Sciences,Beijing 100049,China National Key Laboratory of Science and Technology on Microwave Imaging Institute of Electronics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

The rapid development of compressive sensing(CS)shows that it is possible to recover a sparse signal from very limited *** aperture radar(SAR)imaging based on CS can reconstruct the target scene with a reduced number of collected samples by solving an optimization *** multi-channel SAR imaging based on CS,each channel requires sufficient samples for separate imaging and the total number of samples could still be *** propose an imaging algorithm based on distributed compressive sensing(DCS)that reconstructs scenes jointly under multiple ***-channel SAR imaging based on DCS not only exploits the sparsity of the target scene,but also exploits the correlation among *** requires significantly fewer samples than multi-channel SAR imaging based on *** multiple channels offer different sampling rates,DCS joint processing can reconstruct target scenes with a much more flexible allocation of the number of measurements offered by each channel than that used in separate CS processing.

关键词： synthetic aperture radar multi-channel synthetic aperture radar compressive sensing distributed compressive sensing

Experimental results and analysis of sparse microwave imaging from spaceborne radar raw data

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Science China(Information Sciences) 2012年第8期55卷 1801-1815页

作者： JIANG ChengLong1,2,3,ZHANG BingChen1,2,ZHANG Zhe1,2,3,HONG Wen1,2&wu yirong1,2 1S cience and Technology on Microwave Imaging Laboratory,Beijing 100190,China 2I nstitute of Electronics,Chinese Academy of Sciences,Beijing 100190,China 3G raduate University of Chinese Academy of Sciences,Beijing 100190,China Science and Technology on Microwave Imaging Laboratory Beijing China Institute of Electronics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China

Sparse microwave imaging is a novel radar framework aiming to bring revolutions to the microwave imaging according to the theory of sparse signal *** compressive sensing(CS)is introduced to synthetic aperture radar(SAR)imaging in recent years,the current SAR sparse imaging methods have shown their advantages over the traditional matched filtering ***,the requirement for these methods to process the compressed range data results in the increase of the hardware *** the SAR sparse imaging method that directly uses the raw data is *** paper describes the method of SAR sparse imaging with raw data directly,presents the analysis of the signal-to-noise ratio(SNR)in the echo signal by combining the traditional radar equation with the compressive sensing theory,and provides the tests on 2-D simulated SAR *** simulation results demonstrate the validity of the SNR analysis,and the good performance of the proposed method while a large percentage of the raw data is *** experiment with RadarSat-1 raw data is also carried out to show the feasibility of processing the real SAR data via the method proposed in this *** method is helpful for designing new SAR systems.

关键词： sparse microwave imaging synthetic aperture radar(SAR)imaging compressive sensing signalto-noise ratio raw data

Impaired Spatial Firing Representations of Neurons in the Medial Entorhinal Cortex of the Epileptic Rat Using Microelectrode Arrays

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Research 2024年第2期2023卷 541-552页

作者： Zhaojie Xu Fan Mo Gucheng Yang Penghui Fan Botao Lu Wei Liang Fanli Kong Luyi Jing Wei Xu Juntao Liu Mixia Wang yirong wu Xinxia Cai State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Epilepsy severely impairs the cognitive behavior of *** remains unclear whether epilepsy-induced cognitive impairment is associated with neuronal activities in the medial entorhinal cortex(MEC),a region known for its involvement in spatial *** explore this neural mechanism,we recorded the spikes and local field potentials from MEC neurons in lithium-pilocarpine-induced epileptic rats using self-designed microelectrode *** the open field test,we identified spatial cells exhibiting spatially selective firing properties and assessed their spatial representations in relation to the progression of ***,we analyzed theta oscillations and theta modulation in both excitatory and inhibitory ***,we used a novel object recognition test to evaluate changes in spatial cognitive ability of epileptic *** the epilepsy modeling,the spatial tuning of various types of spatial cells had suffered a rapid and pronounced damage during the latent period(1 to 5 d).Subsequently,the firing characteristics and theta oscillations were *** the chronic period(>10 d),the performance in the novel object experiment *** conclusion,our study demonstrates the detrimental effect on spatial representations and electrophysiological properties of MEC neurons in the epileptic latency,suggesting the potential use of these changes as a"functional biomarker"for predicting cognitive impairment caused by epilepsy.

关键词： epilepsy impaired involvement