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Microstructures,Deformation Mechanisms and Seismic Properties of Synkinematic Migmatite from Southeastern Tibet:Insights from the Migmatitic Core of the Ailao Shan-Red River Shear Zone,Western Yunnan,China

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Journal of Earth Science 2024年第4期35卷 1149-1169页

作者： Weiwei Ma bo zhang Fulong Cai Baoyou Huang Lei zhang Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing100871China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing100085China

Seismic anisotropy originating within the continental crust is commonly used to determine the deformation and kinematic flow within active orogens and is attributed to regionally oriented mica or hornblende ***,naturally deformed rocks usually contain compositional layers(e.g.,parallel compositional banding).It is necessary to understand how both varying mineral contents and differing intensities of compositional layering influence the seismic properties of the deep *** this study,we analyzed the seismic response of migmatitic amphibolite with compositional banding *** present the microstructures,fabrics,calculated seismic velocities,and seismic anisotropies of mylonitic amphibolite from a horizontal shear layer preserved within the Ailao Shan-Red River shear zone,southwestern Yunnan,*** investigated sample is characterized by pronounced centimeter-scale compositional *** microstructures and fabrics suggest that migmatitic amphibolite rocks within deep crust may delineate regions of deformation-assisted,channelized,reactive,porous melt *** origin of compositional banding in the studied migmatitic amphibolite is attributed primarily to partial melting together with some horizontal shearing *** microfabrics and structures investigated in this study are considered to be typical for the base of active horizontal shear layers in the deep crust of southeastern *** responses are modeled by using crystal preferred orientations for minerals of the migmatitic amphibolite by applying the Voigt-Reuss-Hill homogenization *** P-wave and S-wave velocities are largely consistent in the various layers of the ***,seismic anisotropies of P-wave(AV_(p))and S-wave(AVs)are higher in the melanosomes(AV_(p)=5.6%,AV_(s)=6.83%)than those in the leucosomes and the whole rock(AV_(p)=4.2%–4.6%,AV_(s)=3.1%–3.2%).In addition,there is pronounced,S-wave splitting oblique to the foliation plane in the migm

关键词： deformation-assisted melt flow seismic anisotropy microstructure compositional banding migmatite deep crust southeastern Tibet

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Masked Autoencoders as Single Object Tracking Learners

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Computers, Materials & Continua 2024年第7期80卷 1105-1122页

作者： Chunjuan bo XinChen Junxing zhang School of Information and Communication Engineering Dalian Minzu UniversityDalian116600China School of Information and Communication Engineering Dalian University of TechnologyDalian116024China

Significant advancements have beenwitnessed in visual tracking applications leveragingViT in recent years,mainly due to the formidablemodeling capabilities of Vision Transformer(ViT).However,the strong performance of such trackers heavily relies on ViT models pretrained for long periods,limitingmore flexible model designs for tracking *** address this issue,we propose an efficient unsupervised ViT pretraining method for the tracking task based on masked autoencoders,called *** pretraining,we employ two shared-parameter ViTs,serving as the appearance encoder and motion encoder,*** appearance encoder encodes randomly masked image data,while the motion encoder encodes randomly masked pairs of video ***,an appearance decoder and a motion decoder separately reconstruct the original image data and video frame data at the pixel *** this way,ViT learns to understand both the appearance of images and the motion between video frames *** results demonstrate that ViT-Base and ViT-Large models,pretrained with TrackMAE and combined with a simple tracking head,achieve state-of-the-art(SOTA)performance without additional ***,compared to the currently popular MAE pretraining methods,TrackMAE consumes only 1/5 of the training time,which will facilitate the customization of diverse models for *** instance,we additionally customize a lightweight ViT-XS,which achieves SOTA efficient tracking performance.

关键词： Visual object tracking vision transformer masked autoencoder visual representation learning

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Designing Symmetric Gradient Honeycomb Structures with Carbon‑Coated Iron‑Based Composites for High‑Efficiency Microwave Absorption

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Nano-Micro Letters 2024年第11期16卷 224-241页

作者： Yu zhang Shu‑Hao Yang Yue Xin bo Cai Peng‑Fei Hu hai‑Yang Dai Chen‑Ming Liang Yun‑Tong Meng Ji‑Hao Su Xiao‑Juan zhang Min Lu Guang‑Sheng Wang School of Chemistry Beihang UniversityBeijing 100191People’s Republic of China School of Electronics and Information Zhengzhou University of Light IndustryZhengzhou 450002People’s Republic of China School of Chemical Engineering Northeast Electric Power UniversityJilin 132000People’s Republic of China College of Chemistry and Materials Engineering Beijing Technology and Business UniversityBeijing 100048People’s Republic of China

The impedance matching of absorbers is a vital factor affecting their microwave absorption(MA)*** this work,we controllably synthesized Material of Institute Lavoisier 88C(MIL-88C)with varying aspect ratios(AR)as a precursor by regulating oil bath conditions,followed by one-step thermal decomposition to obtain carbon-coated iron-based *** the precursor MIL-88C(Fe)preparation conditions,such as the molar ratio between metal ions and organic ligands(M/O),oil bath temperature,and oil bath time,influenced the phases,graphitization degree,and AR of the derivatives,enabling low filler loading,achieving well-matched impedance,and ensuring outstanding MA *** MOF-derivatives 2(MD_(2))/polyvinylidene Difluoride(PVDF),MD_(3)/PVDF,and MD4/PVDF absorbers all exhibited excellent MA properties with optimal filler loadings below 20 wt%and as low as 5 wt%.The MD_(2)/PVDF(5 wt%)achieved a maximum effective absorption bandwidth(EAB)of 5.52 GHz(1.90 mm).The MD_(3)/PVDF(10 wt%)possessed a minimum reflection loss(RL_(min))value of−67.4 at 12.56 GHz(2.13 mm).A symmetric gradient honeycomb structure(SGHS)was constructed utilizing the high-frequency structure simulator(HFSS)to further extend the EAB,achieving an EAB of 14.6 GHz and a RL_(min) of−59.0 *** research offers a viable inspiration to creating structures or materials with high-efficiency MA properties.

关键词： MIL-88C(Fe) Fe/Fe_(3)O_(4)/Fe_(3)C@C Controllable preparation Symmetric gradient honeycomb structure Microwave absorbing

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Performance improvements in complementary metal oxide semiconductor devices and circuits based on fin field-effect transistors using 3-nm ferroelectric Hf_(0.5)Zr_(0.5)O_(2)

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Rare Metals 2024年第7期43卷 3242-3249页

作者： Zhao-Hao zhang Yan-Na Luo Gao-bo Xu Jia-Xin Yao Zhen-Hua Wu Hong-Bin Zhao Qing-Zhu zhang Hua-Xiang Yin Jun Luo Wen-Wu Wang hai-Ling Tu Integrated Circuit Advanced R&D Center Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029China School of Integrated Circuits University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous MetalsBeijing 100088China

In this work,a conventional HfO_(2) gate dielectric layer is replaced with a 3-nm ferroelectric(Fe) HZO layer in the gate stacks of advanced fin field-effect transistors(FinFETs).Fe-induced characteristics,e.g.,negative drain induced barrier lowering(N-DIBL) and negative differential resistance(NDR),are clearly observed for both p-and n-type HZO-based *** characteristics are attributed to the enhanced ferroelectricity of the 3-nm hafnium zirconium oxide(HZO) film,caused by Al doping from the TiAlC capping *** mechanism is verified for capacitors with structures similar to the *** to the enhanced ferroelectricity and N-DIBL phenomenon,the drain current(I_(DS))of the HZO-FinFETs is greater than that of HfO_(2)-FinFETs and obtained at a lower operating ***,circuits based on HZO-FinFET achieve higher performance than those based on HfO_(2)-FinFET at a low voltage drain(V_(DD)),which indicates the application feasibility of the HZO-FinFETs in the ultralow power integrated circuits.

关键词： FinFET Ferroelectric Hafnium zirconium oxide Subthreshold swing Low power

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Cooperative User-Scheduling and Resource Allocation Optimization for Intelligent Reflecting Surface Enhanced LEO Satellite Communication

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China Communications 2024年第2期21卷 227-244页

作者： Meng Meng bo Hu Shanzhi Chen Jianyin zhang State Key Lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Lab of Wireless Mobile Communication China Academy of Telecommunication TechnologyBeijing 100191China Research Institute of China Mobile Beijing 100053China

Lower Earth Orbit(LEO) satellite becomes an important part of complementing terrestrial communication due to its lower orbital altitude and smaller propagation delay than Geostationary satellite. However, the LEO satellite communication system cannot meet the requirements of users when the satellite-terrestrial link is blocked by obstacles. To solve this problem, we introduce Intelligent reflect surface(IRS) for improving the achievable rate of terrestrial users in LEO satellite communication. We investigated joint IRS scheduling, user scheduling, power and bandwidth allocation(JIRPB) optimization algorithm for improving LEO satellite system *** optimization problem of joint user scheduling and resource allocation is formulated as a non-convex optimization problem. To cope with this problem, the nonconvex optimization problem is divided into resource allocation optimization sub-problem and scheduling optimization sub-problem firstly. Second, we optimize the resource allocation sub-problem via alternating direction multiplier method(ADMM) and scheduling sub-problem via Lagrangian dual method ***, we prove that the proposed resource allocation algorithm based ADMM approaches sublinear convergence theoretically. Finally, we demonstrate that the proposed JIRPB optimization algorithm improves the LEO satellite communication system throughput.

关键词： convex optimization intelligent reflecting surface LEO satellite communication OFDM

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A NEW GLOBAL OPTIMIZATION ALGORITHM FOR MIXED-INTEGER QUADRATICALLY CONSTRAINED QUADRATIC FRACTIONAL PROGRAMMING PROBLEM

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Journal of Computational Mathematics 2024年第3期42卷 784-813页

作者： bo zhang Yuelin Gao Xia Liu Xiaoli Huang School of Civil and Hydraulic Engineering School of Mathematics and StatisticsNingxia UniversityYinchuan 750021China School of Mathematics and Information Science North Minzu UniversityYinchuan 750021China Ningxia Province Key Laboratory of Intelligent Information and Data Processing Yinchuan 750021China School of Mathematics and Statistics Ningxia UniversityYinchuan 750021China

The mixed-integer quadratically constrained quadratic fractional programming(MIQCQFP)problem often appears in various fields such as engineering practice,management science and network ***,most of the solutions to such problems are often designed for their unique *** paper puts forward a new global optimization algorithm for solving the problem *** first convert the MIQCQFP into an equivalent generalized bilinear fractional programming(EIGBFP)problem with integer ***,we linearly underestimate and linearly overestimate the quadratic functions in the numerator and the denominator respectively,and then give a linear fractional relaxation technique for EIGBFP on the basis of non-negative *** that,combining rectangular adjustment-segmentation technique and midpointsampling strategy with the branch-and-bound procedure,an efficient algorithm for solving MIQCQFP globally is ***,a series of test problems are given to illustrate the effectiveness,feasibility and other performance of this algorithm.

关键词： Global optimization Branch and bound Quadratic fractional programming Mixed integer programming

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Dynamics of the spatiotemporal velocity of glaciers on the eastern slope of Mount Gongga,China,under climate change

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Advances in Climate Change Research 2024年第3期15卷 490-499页

作者： Yin FU bo zhang Qiao LIU Guo-Xiang LIU Rui zhang Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China

The quantitative assessment of glacier flow velocity dynamics plays a pivotal role in understanding its response mechanisms concerning climate *** work provides a systematic quantitative assessment of the deceleration status of glaciers in this region by investigating the motion evolution of typical glaciers in Mount Gongga in recent years,thereby revealing the seasonal dynamics and inter-annual evolution over an extensive time *** used the optical flow-small baseline subset(OF-SBAS)method to compute the time-series velocities of the hai-luogou Glacier and the Mozigou Glacier using 178 archived Sentinel-1 satellite synthetic aperture radar(SAR)images from 2014 to *** findings revealed a prominent seasonal pattern in glacier motion,characterised by cyclic variations in velocity from cold to warm ***,we identified variations in velocities across distinct regions of the glacier surface,underscored by the lag in the peak time node of glacier flow with increasing *** pattern may have been determined by a combination of internal and external factors,including mass accumulation and ablation-driven subglacial drainage,as well as the glacier geomorphological ***,during 2015-2021,the glaciers on the eastern slope of Mount Gongga exhibited an overarching trend of ***,the ablation area of the hailuogou Glacier recorded the most substantial deceleration,exceeding 8%per *** study underscores the efficacy of the OF-SBAS method in extracting long-term glacier *** work also establishes a robust foundation for the analysis of spatiotemporal fluctuations in glacier movement within the context of climate warming.

关键词： Monsoonal temperate glaciers Synthetic aperture radar(SAR) Glacier movement hailuogou glacier Mozigou glacier Optical flow-small baseline subset(OF-SBAS)

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On Depolymerization

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CCS Chemistry 2024年第2期6卷 297-312页

作者： bo Qin Xi zhang College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082 Department of Chemistry Tsinghua UniversityBeijing 100084

Polymers have become an essential part of modern life and the global economy on account of their costeffectiveness and versatile ***,most postconsumer polymer wastes are unrecycled,leading to environmental pollution and resource ***,as an efficient chemical recycling approach,holds great promise in establishing a circular polymer *** this review,we attempt to highlight recent and significant advancements in depolymerization *** key research topics are discussed:(1)depolymerization of commodity polymers to produce reusable monomers and high-value chemicals;(2)depolymerization of intrinsically depolymerizable *** is anticipated that this review will reflect the present status and future trends of this rapidly evolving realm of depolymerization.

关键词： depolymerization chemical recycling sustainable polymers circular polymer economy catalysis dynamic covalent chemistry

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Metal–Organic Framework‑Based Photodetectors

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Nano-Micro Letters 2024年第11期16卷 675-703页

作者： Jin‑Biao zhang Yi‑bo Tian Zhi‑Gang Gu Jian zhang State Key Laboratory of Structural Chemistry Structure of MatterFujian Institute of ResearchChinese Academy of SciencesFuzhouFujian 350002People’s Republic of China College of Chemistry and Materials Science Fujian Nornal UniversityFuzhou 350007FujianPeople’s Republic of China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108FujianPeople’s Republic of China University of Chinese Academy of Science Beijing 100049People’s Republic of China

The unique and interesting physical and chemical properties of metal–organic framework(MOF)materials have recently attracted extensive attention in a new generation of photoelectric *** this review,we summarized and discussed the research progress on MOF-based *** methods of preparing MOF-based photodetectors and various types of MOF single crystals and thin film as well as MOF composites are introduced in ***,the photodetectors applications for X-ray,ultraviolet and infrared light,biological detectors,and circularly polarized light photodetectors are ***,summaries and challenges are provided for this important research field.

关键词： Metal-organic frameworks Semiconductor Photodetectors

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Investigation of control effects of end-wall selfadaptive jet on three-dimensional corner separation of a highly loaded compressor cascade

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Chinese Journal of Aeronautics 2024年第6期37卷 109-126页

作者： Hejian WANG bo LIU Xiaochen MAO botao zhang Zonghao YANG School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China The National Key Laboratory of Science and Technology on Aerodynamic Design and Research Xi’an 710129China Taihang Laboratory Chengdu 610000China

To overcome the limitations posed by three-dimensional corner separation,this paper proposes a novel flow control technology known as passive End-Wall(EW)self-adaptive *** single EW slotted schemes(EWS1 and EWS2),alongside a combined(COM)scheme featuring double EW slots,were *** results reveal that the EW slot,driven by pressure differentials between the pressure and suction sides,can generate an adaptive jet with escalating velocity as the operational load *** high-speed jet effectively re-excites the local low-energy fluid,thereby mitigating the corner ***,the EWS1 slot,positioned near the blade leading edge,exhibits relatively low jet velocities at negative incidence angles,causing jet separation and exacerbating the corner ***,the EWS2 slot is close to the blade trailing edge,resulting in massive low-energy fluid accumulating and separating before the slot outlet at positive incidence *** contrast,the COM scheme emerges as the most effective solution for comprehensive corner separation *** can significantly reduce the total pressure loss and improve the static pressure coefficient for the ORI blade at 0°-4° incidence angles,while causing minimal negative impact on the aerodynamic performance at negative incidence ***,the corner stall is delayed,and the available incidence angle range is broadened from -10°--2°to -10°-4°.This holds substantial promise for advancing the aerodynamic performance,operational stability,and load capacity of future highly loaded compressors.

关键词： Three-dimensional corner separation End-wall adaptive jet Total pressure loss Highly loaded compressor cascade Compressors

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