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Learning the imaging mechanism directly from optical microscopy observations

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Photonics Research 2024年第1期12卷 7-26页

作者： ZE-HAO WANG LONG-KUN SHAN TONG-tian WENG tian-LONG CHEN xiang-DONG CHEN ZHANG-YANG WANG GUANG-CAN guo FANG-WEN SUN CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China University of Texas at Austin AustinTexas 78705USA Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

The optical microscopy image plays an important role in scientific research through the direct visualization of the nanoworld,where the imaging mechanism is described as the convolution of the point spread function(PSF)and *** on a priori knowledge of the PSF or equivalent PSF,it is possible to achieve more precise exploration of the ***,it is an outstanding challenge to directly extract the PSF from microscopy ***,with the help of self-supervised learning,we propose a physics-informed masked autoencoder(PiMAE)that enables a learnable estimation of the PSF and emitters directly from the raw microscopy *** demonstrate our method in synthetic data and real-world experiments with significant accuracy and noise *** outperforms DeepSTORM and the Richardson–Lucy algorithm in synthetic data tasks with an average improvement of 19.6%and 50.7%(35 tasks),respectively,as measured by the normalized root mean square error(NRMSE)*** is achieved without prior knowledge of the PSF,in contrast to the supervised approach used by DeepSTORM and the known PSF assumption in the Richardson–Lucy *** method,PiMAE,provides a feasible scheme for achieving the hidden imaging mechanism in optical microscopy and has the potential to learn hidden mechanisms in many more systems.

关键词： optical emitter mechanism

Regio-and Stereoselective Polymerization of Bio-based Ocimene by Rare-Earth Metal Catalysts

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Chinese Journal of Polymer Science 2024年第2期42卷 223-229,I0008页

作者： Qi-Yuan Wang Li-Peng Sang Zhen Zhang Yang Jiang Hui tian Xia Zhao xiang guo Shi-Hui Li State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechonologyXiangyang441003China Shanxi Coal Chemical Industry Technology Research Institute Xi’an710000China Hubei Institute of Aerospace Chemotechonology Xiangyang441003China

Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.

关键词： Biobased monomer Terpenes Ocimene Rare-earths Polymerization Regio/stereoselectivity Elastomer

A Compact UHF Antenna Based on Hilbert Fractal Elements and a Serpentine Arrangement for Detecting Partial Discharg

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Energy Engineering 2024年第5期121卷 1127-1141页

作者： xiang Lin Jian Fang Ming Zhang Kuang Yin Yan tian Yingfei guo Qianggang Wang Guangzhou Power Supply Bureau of Guangdong Power Grid Co. Ltd.China Southern Power GridGuangzhou510620China State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqing400044China

Efforts to protect electric power systems from faults have commonly relied on the use of ultra-high frequency(UHF)antennas for detecting partial discharge(PD)as a common precursor to ***,the effectiveness of existing UHF antennas suffers from a number of challenges such as limited bandwidth,relatively large physical size,and low detection *** present study addresses these issues by proposing a compact microstrip patch antenna with fixed dimensions of 100 mm×100 mm×1.6 *** results of computations yield an optimized antenna design consisting of 2nd-order Hilbert fractal units positioned within a four-layer serpentine arrangement with a fractal unit connection distance of 3.0 ***,the optimized antenna design achieves a detection bandwidth for which the voltage standing wave ratio is less than 2 that is approximately 97.3%of the UHF frequency range(0.3–3 GHz).Finally,a prototype antenna is fabricated using standard printed circuit board technology,and the results of experiments demonstrate that the proposed antenna is capable of detecting PD signals at a distance of 8 m from the discharge source.

关键词： Power system fault partial discharge UHF antenna fractal antenna micro-strip antenna

Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： Jing-Jing guo Kai-xiang Di Lie-Hui Zhang Yu-Long Zhao Hui-Ying Tang Rui-Han Zhang Ye tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NMR)were carried *** showed that NMR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition Migration Soaking NMR T_(2)spectra Propped fracture Permeability recovery

Electrochemical anodic oxidation assisted fabrication of memristors

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International Journal of Extreme Manufacturing 2024年第3期6卷 250-272页

作者： Shuai-Bin Hua tian Jin Xin guo School of Materials Science and Engineering State Key Laboratory of Material Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074People’s Republic of China

Owing to the advantages of simple structure,low power consumption and high-density integration,memristors or memristive devices are attracting increasing attention in the fields such as next generation non-volatile memories,neuromorphic computation and data ***,the deposition of memristive films often requires expensive equipment,strict vacuum conditions,high energy consumption,and extended processing *** contrast,electrochemical anodizing can produce metal oxide films quickly(e.g.10 s) under ambient *** means of the anodizing technique,oxide films,oxide nanotubes,nanowires and nanodots can be fabricated to prepare *** film thickness,nanostructures,defect concentrations,etc,can be varied to regulate device performances by adjusting oxidation parameters such as voltage,current and *** memristors fabricated by the anodic oxidation technique can achieve high device consistency,low variation,and ultrahigh yield *** article provides a comprehensive review of the research progress in the field of anodic oxidation assisted fabrication of ***,the principle of anodic oxidation is introduced;then,different types of memristors produced by anodic oxidation and their applications are presented;finally,features and challenges of anodic oxidation for memristor production are elaborated.

关键词： anodic oxidation anodized aluminium oxide memristor resistive switching electrical properties

Frost heaving and crack initiation characteristics of tunnel rock mass in cold regions under low-temperature degradation

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Journal of Mountain Science 2024年第8期21卷 2844-2854页

作者： CHEN Wenhua xiang tian School of Civil Engineering Beijing Jiaotong UniversityBeijing 202303China

Water freezing in rock fractures causes volumetric expansion and fracture development through frost *** study introduces a novel analytical model to investigate how uneven freezing force and surrounding rock pressure influence fracture initiation,based on mass conservation,elasticity,and water-ice phase transition principles.A model for rock fracture initiation considering freezing temperature,uneven freezing expansion,in-situ stress,and lateral pressure was proposed based on fracture *** for stress intensity factors were developed and validated using the phase field *** effects of rock elastic modulus anisotropy and critical fracture energy density on fracture initiation were also *** results show that the values of KI and KII exhibit an upward trend as the freezing temperature,uneven expansion,in-situ stress,and lateral pressure *** uneven freezing expansion has the most significant influence on KI and KII values among these *** the uneven freezing expansion coefficient increases to 0.5,the fracture initiation mode shifts from tensile fracture to shear *** the lateral pressure coefficient increases to 1,the fracture initiation mode shifts from tensile fracture to shear *** elastic modulus anisotropy causes fractures to propagate in a clockwise direction,forming a'butterfly'*** fracture energy density an isotropy causes counterclockwise deviation in propagation direction,resulting in branching paths and an'H'-shaped pattern.

关键词： Rock fractures Fracture water Uneven freezing expansion Phase field method Initiation angle Anisotropy

Designing High-Porosity Porous Structures with Complex Geometries for Enhanced Thermal Conductivity Using Selective Laser Melting and Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 808-824页

作者： Hulin Tang xiang Zhang Chenping Zhang tian Zhou Shiyue guo Gaopeng Xu Rusheng Zhao Boyoung Hur Xuezheng Yue School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200082China National Center for Stomatology National Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyDepartment of Oral Maxillofacial-Head and Neck OncologyShanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineCollege of StomatologyShanghai Jiao Tong UniversityShanghai 200011China Longzhong Lab Wuhan of Science and TechnologyYancheng 224000China Tokyo Metropolitan University TokyoJapan Gyeongsang National University JinjuKorea

Rapid advancements in the aerospace industry necessitate the development of unified,lightweight and thermally conductive *** complex geometries,including bionic and porous structures,is paramount in thermally conductive structures to attain improved thermal *** design of two high-porosity porous lattice structures was inspired by pomelo peel structure,using Voronoi parametric *** combining characteristic elements of two high-porostructuressity porous lattice structures designed,a novel high-porosity porous gradient structure is *** structure is based on gradient *** selective laser melting(SLM),fabrication comprises ***-state thermal characteristics are evaluated via finite element analysis(FEA).The experimental thermal conductivity measurements correlate well with simulation results,validating the sequence of K_L as the highest,followed by D_K_L and then D_*** treatment significantly improves thermal conductivity,enhancing the base material by about 45.6%and porous structured samples by approximately 43.7%.

关键词： Selective laser melting Porous lattice structure Thermal conductivity Heat treatment

A Fractional-Order Ultra-Local Model-Based Adaptive Neural Network Sliding Mode Control of n-DOF Upper-Limb Exoskeleton With Input Deadzone

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 760-781页

作者： Dingxin He HaoPing Wang Yang tian Yida guo the School of Automation Nanjing University of Science and TechnologyNanjing 210094China IEEE Norinco Group Institute of Navigation and Control Technology Beijing 100089China

This paper proposes an adaptive neural network sliding mode control based on fractional-order ultra-local model for n-DOF upper-limb exoskeleton in presence of uncertainties,external disturbances and input *** the model complexity and input deadzone,a fractional-order ultra-local model is proposed to formulate the original dynamic system for simple controller ***,the control gain of ultra-local model is considered as a *** fractional-order sliding mode technique is designed to stabilize the closed-loop system,while fractional-order time-delay estimation is combined with neural network to estimate the lumped ***,a fractional-order ultra-local model-based neural network sliding mode controller(FO-NNSMC) is ***,to avoid disadvantageous effect of improper gain selection on the control performance,the control gain of ultra-local model is considered as an unknown ***,the Nussbaum technique is introduced into the FO-NNSMC to deal with the stability problem with unknown ***,a fractional-order ultra-local model-based adaptive neural network sliding mode controller(FO-ANNSMC) is ***,the stability analysis of the closed-loop system with the proposed method is presented by using the Lyapunov ***,with the co-simulations on virtual prototype of 7-DOF iReHave upper-limb exoskeleton and experiments on 2-DOF upper-limb exoskeleton,the obtained compared results illustrate the effectiveness and superiority of the proposed method.

关键词： Adaptive control input deadzone model-free control n-DOF upper-limb exoskeleton neural network

Recent progress of two-dimensional metal-base catalysts in urea oxidation reaction

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Rare Metals 2024年第8期43卷 3607-3633页

作者： Qi-xiang Huang Fang Wang Yong Liu Bi-Ying Zhang Fang-Ya guo Zhong-Qiu Jia Hao Wang tian-xiang Yang Hai-Tao Wu Feng-Zhang Ren Ting-Feng Yi School of Materials Science and Engineering Henan University of Science and Technology School of Environmental Engineering and Chemistry Luoyang Institute of Science and Technology Henan Province International Joint Laboratory of Materials for Solar Energy Conversion and Lithium Sodium Based Battery School of Chemistry and Life Sciences Suzhou University of Science and Technology School of Materials Science and Engineering Northeastern University

Urea oxidation reaction(UOR) is an auxiliary water electrolysis hydrogen production technology developed in recent years to replace oxygen evolution reaction and reduce energy consumption,which can produce hydrogen more efficiently by low theoretical potential,reduce the average cost of electrochemical hydrogen production,and is a frontier research hotspot for renewable hydrogen ***-dimensional(2D) nanomaterials as electrocatalysts have many favorable potential,such as it can effectively reduce the resistivity of materials and increase the specific surface area with *** paper reviews the application of 2D materials in UOR in alkaline *** a cross-sectional comparison of various material performance data including overpotential,Tafel slope,electrochemical active surface area(ECSA) and it stability test was conducted,which could illustrate the differences between materials composed of different *** addition,the main challenges hindering the progress of research on 2D materials in urea electrocatalysis processes and promising materials in this field in future are summarized and *** is believed that this review will contribute to designing and analyzing highperformance 2D urea electrocatalysts for water splitting.

关键词： Water splitting Urea oxidation reaction Two-dimensional Transition metal compounds Nobleon-noble metals