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The in-situ parasitic microstructure interface and defect formation mechanism in (010) β-Ga_(2)O_(3) epitaxial film via MOCVD

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Science China Materials 2025年第2期68卷 515-522页

作者： xianqiang Song Yunlong He Zhan Wang xiaoli Lu jing Sun Ying Zhou Yang Liu Jiatong Fan xiaoning He Xuefeng Zheng xiaohua Ma Yue Hao State Key Laboratory of Wide-Bandgap Semiconductor Devices and Integrated Technology National Engineering Research Center of Wide Band-Gap SemiconductorSchool of MicroelectronicsXidian UniversityXi’an 710071China School of electronic Engineering Xi’an University of Posts&TelecommunicationsXi’an 710121China Guangzhou Institute of Technology Xidian UniversityGuangzhou 510555China Shaanxi Semiconductor Industry Association Xi’an 710065China

In this study, a typical hillock surface defect wasdiscovered in (010) β-Ga_(2)O_(3) thin films grown by metal-organicchemical vapor deposition (MOCVD), and the morphologyand structure were systematically investigated. The observeddefects exhibit a polygonal shape with a ridge-like hillockalong the [001] direction. Transmission electron microscopy(TEM) microanalysis reveals that polygonal hillock defects arecomposed of twin grains forming an inverted pyramid shapeembedded in the epitaxial layer, which exhibits twofold rotational symmetry along the [100] crystal direction. Theboundary between the defective and perfect lattices appearsband-like, characterized by complex faults, with structuralrelationships between the twin region and the matrix identified as [001]matrix||[010]Defect and {−310}matrix||{−201}Defect. Theorigin of surface defects in the (010) β-Ga_(2)O_(3) homoepitaxiallayers could be attributed not only to the extent of substratedefects but also to epitaxial process conditions. The definitiveexplanation is the localized aggregation of gallium atoms/oxygen vacancies during the growth process, as evidenced byenergy-dispersive X-ray (EDX) analysis and optimized experiments. This work provides brand-new perspectives intothe study of defects in β-Ga_(2)O_(3) epitaxial films, which furtheradvances the application of Ga_(2)O_(3) materials in power devicetechnologies.

关键词： β-Ga_(2)O_(3) MOCVD surface defect

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Dielectric-ion-conductive ZnNb_(2)O_(6) layer enabling rapid desolvation and diffusion for dendrite-free Zn metal batteries

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Journal of Energy Chemistry 2025年第1期100卷 693-701页

作者： Haifeng Yang Jian Wang Panpan Zhang xiaomin Cheng Qinghua Guan jing Dong Bixian Chen Lujie Jia jing Zhang Yongzheng Zhang Yunjian Liu Hongzhen Lin School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina i-Lab&CAS Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123JiangsuChina Helmholtz Institute Ulm(HIU) Ulm D89081Germany School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048ShaanxiChina Karlsruhe Institute of Technology(KIT) Karlsruhe D76021Germany State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

Rechargeable aqueous zinc-metal batteries (AZMBs) are promising candidates for large-scale energy storage systems due to their low cost and high ***,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn(H_(2)O)_(6)^(2+)solvation ***,learnt from self-generated solid electrolyte interphase (SEI) in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface (ZNB@Zn),acting as a rapid desolvation *** zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical ***,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility (99.54%) even under high current density and depth of discharge ***,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g^(-1)and outstanding rate performance up to 10 A g^(-1).The large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs.

关键词： Zn metal battery Dielectri cartificial layer Rapid ion diffusion Zincophilic diffusion Active water inhibition

A probabilistic model with multi-dimensional features for object extraction

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Frontiers of Computer Science 2012年第5期6卷 513-526页

作者： jing WANG Zhijing LIU Hui ZHAO School of Computer Science and Technology Xidian UniversityXi'an 710071China School of electronic and Information Engineering Xi'an Jiaotong UniversityXi'an 710049China

To identify recruitment information in different domains, we propose a novel model of hierarchical tree- structured conditional random fields （HT-CRFs）. In our ap- proach, first, the concept of a Web object （WOB） is discussed for the description of special Web information. Second, in contrast to traditional methods, the Boolean model and multi- rule are introduced to denote a one-dimensional text feature for a better representation of Web objects. Furthermore, a two-dimensional semantic texture feature is developed to dis- cover the layout of a WOB, which can emphasize the struc- tural attributes and the specific semantics term attributes of WOBs. Third, an optimal WOB information extraction （IE） based on HT-CRF is performed, addressing the problem of a model having an excessive dependence on the page structure and optimizing the efficiency of the model＇s training. Finally, we compare the proposed model with existing decoupled ap- proaches for WOB IE. The experimental results show that the accuracy rate of WOB IE is significantly improved and that time complexity is reduced.

关键词： feature extraction conditional random fields(CRFs) information extraction (IE)

Integrated Sliding Mode Velocity Control of Linear Permanent Magnet Synchronous Motor with Thrust Ripple Compensation

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CES Transactions on Electrical Machines and Systems 2023年第1期7卷 100-109页

作者： Cong Bai Zhonggang Yin jing Liu Yanqing Zhang xiangdong Sun the Department of Electrical Engineering Xi'an University of TechnologyXi'an710048China IEEE the Department of electronic Engineering Xi'an University of TechnologyXi'an710048China

In this paper,a compound sliding mode velocity control scheme with a new exponential reaching law(NERL)with thrust ripple observation strategy is proposed to obtain a high performance velocity loop of the linear permanent magnet synchronous motor(LPMSM)control system.A sliding mode velocity controller based on NERL is firstly discussed to restrain chattering of the conventional exponential reaching law(CERL).Furthermore,the unavoidable thrust ripple caused by the special structure of linear motor will bring about velocity fluctuation and reduced control ***,a thrust ripple compensation strategy on the basis of extend Kalman filter(EKF)theory is *** estimated thrust ripple will be introduced into the sliding mode velocity controller to optimize the control accuracy and *** effectiveness of the proposal is validated with experimental results.

关键词： Linear permanent magnet synchronous motor(LPMSM) Sliding mode velocity control New exponential reaching law Thrust ripple compensation

Bright-Dark Mode Coupling Model of Plasmons

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Chinese Physics Letters 2020年第3期37卷 50-54页

作者： jing Zhang Yong-Gang Xu Jian-xin Zhang Lu-Lu Guan Yong-Fang Li School of Physics and Information Technology Shaanxi Normal UniversityXi'an 710119 School of electronic Engineering Xi'an Shiyou UniversityXi'an 710065 School of Science Xi'an University of Posts and TelecommunicationsXi'an 710121

We propose a coupling model to describe the interaction between the bright and dark modes of the plasmons of a dimer composed of two orthogonal gold nano-rods(GNRs),referred to as the BDMC *** model shows that the eigen-frequencies of the coupled plasmons are governed by Coulomb potential and electrostatic *** the BDMC model,the behaviors of the coupling coefficient and the frequency offset,which is a new parameter introduced here,are ***,the asymmetric behavior of two eigen-frequencies related to gap of two GNRs is *** the harmonic oscillator model and the coupled parameters obtained by the BDMC model,the bright mode absorption spectra of the dimer are calculated and the results agree with the numerical simulation.

关键词： potential. coupling dimer

Stable structures and properties of Ru_(2)Al_(5)

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Chinese Physics B 2025年第1期34卷 414-420页

作者： jing Luo Meiguang Zhang xiaofei Jia Qun Wei School of Physics Xidian UniversityXi’an 710071China College of Physics and Optoelectronic Technology Baoji University of Arts and SciencesBaoji 721016China

Novel ordered intermetallic compounds have stimulated much ***–Al alloys are a prominent class of hightemperature structural materials,but the experimentally reported crystal structure of the intermetallic Ru_(2)Al_(5) phase remains elusive and *** resolve this controversy,we extensively explored the crystal structures of Ru_(2)Al_(5) using first-principles calculations combined with crystal structure prediction *** the calculated x-ray diffraction patterns and lattice parameters of five candidate Ru2Al5structures,those of the orthorhombic Pmmn structure best aligned with recent experimental *** structural stabilities of the five Ru_(2)Al_(5)structures were confirmed through formation energy,elastic constants,and phonon spectrum *** also comprehensively analyzed the mechanical and electronic properties of the five *** work can guide the exploration of novel ordered intermetallic compounds in Ru–Al alloys.

关键词： crystal structure prediction mechanical properties first-principles calculations

Hyperspectral remote sensing images terrain classification in DCT SRDA subspace

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The Journal of China Universities of Posts and Telecommunications 2015年第1期22卷 65-71页

作者： Liu jing Liu Yi School of electronic Engineering Xi'an University of Posts and Telecommunications School of electronic Engineering Xidian University

Hyperspectral remote sensing images terrain classification faces the problems of high data dimensionality and lack of labeled training data, resulting in unsatisfied terrain classification efficiency. The feature extraction is required before terrain classification for preserving discriminative information and reducing data dimensionality. A hyperspectral remote sensing images feature extraction method, i.e., discrete cosine transform （DCT） spectral regression discriminant analysis （SRDA） subspace method, was presented to solve the above problems. The proposed DCT SRDA subspace method firstly takes DCT in the original spectral space and gets the DCT coefficients of each pixel spectral curve; secondly performs SRDA in the DCT coefficients space and obtains the DCT SRDA subspace. Minimum distance classifier was designed in the resulting DCT SRDA subspace to evaluate the feature extraction performance. Experiments for two real airborne visible/infrared imaging spectrometer （AVIRIS） hyperspectral images show that, comparing with spectral LDA subspace method, the proposed DCT SRDA subspace method can improve terrain classification efficiency.

关键词： terrain classification spectral regression discriminant analysis feature extraction hyperspectral remote sensing image

Improved energy storage performance of bismuth sodium titanate-based lead-free relaxor ferroelectric ceramics via Bi-containing complex ions doping

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Rare Metals 2023年第5期42卷 1472-1482页

作者： Wen-jing Shi Lei-Yang Zhang Yu-Le Yang D.O.Alikin V.Ya.Shur xiao-Yong Wei Hong-Liang Du Li Jin electronic Materials Research Laboratory Key Laboratory of the Ministry of Education and International Center for Dielectric ResearchSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an710049China School of Natural Sciences and Mathematics Ural Federal UniversityEkaterinburg620000Russia Multifunctional electronic Ceramics Laboratory College of EngineeringXi’an International UniversityXi’an710077China

Lead-free dielectric ceramics can be used to make quick charge-discharge capacitor devices due to their high power *** use in advanced electronic systems,however,has been hampered by their poor energy storage performance(ESP),which includes low energy storage efficiency and recoverable energy storage density(Wrec).In this work,we adopted a combinatorial optimization strategy to improve the ESP in(Bi_(0.5)Na_(0.5))TiO_(3)(BNT)-based relaxor ferroelectric *** begin,the Bi-containing complex ions Bi(Mg_(2/3)Nb_(1/3))O_(3)(BMN)were introduced into a BNT-based matrix in order to improve the diffuse phase transition,increase Bi-O bond coupling,avoid macro domain development,and limit polarization response ***,the viscous polymer process was employed to reduce sample thickness and porosity,resulting in an apparent increase in breakdown strength in(1-x)[0.7(Bi_(1/2)Na_(1/2))TiO_(3)]-0.3SrTiO_(3)-xBi(Mg_(2/3)Nb_(1/3))O_(3)(BS-xBMN)***,in x=0.20 composition,an amazing Wrecof 5.62 J·cm^(-3)and an ultra-high efficiency of 91.4%were simultaneously achieved at a relatively low field of 330 kV·cm^(-1),together with remarkable temperature stability in the temperature range of 30-140℃(3.5 J·cm^(-3)±5%variation).This research presents a new lead-free dielectric material with superior ESP for use in pulsed power capacitors.

关键词： Relaxor ferroelectric Energy storage performance(ESP) Viscous polymer process (Bi_(0.5)Na_(0.5))TiO_(3)(BNT)

An improved secondary electrons energy spectrum model and its application in multipactor discharge

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Chinese Physics B 2018年第3期27卷 502-507页

作者： Wan-Zhao Cui Heng Zhang Yun Li Yun He Qi Wang Hong-Tai Zhang Hong-Guang Wang jing Yang National Key Laboratory of Science and Technology on Space Microwave China Academy of Space Technology(Xi'an)Xi'an 710100China School of electronic and Information Engineering Xi'an Jiaotong UniversityXi'an 710049China

Secondary electron emission(SEE)of metal and dielectric materials plays a key role in multipactor discharge,which is a bottle neck problem for high-power satelliate *** of both the secondary electron yield(SEY)and the secondary electron energy spectrum(SES)are performed on metal samples for an accurate description of the real SEE *** order to simplify the fitting process and improve the simulation efficiency,an improved model is proposed for the description of secondary electrons(SE)emitted from the material surface,including true,elastic,and inelastic *** the novel SES model into the electromagnetic particle-in-cell method,the electronic resonant multipactor in microwave components is simulated successfully and hence the discharge threshold is *** results of the SES variation in the improved model demonstrate that the multipactor threshold is strongly dependent on *** addition,the mutipactor simulation results agree quite well with the experiment for the practical microwave component,while the numerical model of SEY and SES fits well with the sample data taken from the microwave component.

关键词： secondary electron energy spectrum multipactor simulation vaccum breakdown satellite application