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Recent progress on the synthesis of defective UiO-66 for thermal catalysis

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Nano Research 2024年第10期17卷 8653-8670页

作者： Qing Feng Caoyu Yang Lin Chang Guodong Li zhiyong Tang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 100049China

Zirconium terephthalate UiO-66 has aroused great interest in catalysis since it exhibits significant flexibility and compatibility for accommodating a high number of defects as well as exceptional thermal and chemical *** now,many works have focused on the modulations of the Zr6-oxo clusters in UiO-66 in terms of diverse synthesis,advanced characterizations,and their catalytic *** achieve high catalytic efficiency,it is still highly desired for rationally constructing and modulating the Zr6-oxo clusters with exposed catalytic sites and diverse microenvironments for advanced *** this review,we provide a comprehensive summary of recent progress on the synthesis of defective UiO-66,qualitative and quantitative characterizations,as well as a logical overview of heterogeneous catalytic applications over the past few ***,the outlooks for the research paradigm of defective UiO-66 are discussed.

关键词： defective UiO-66 de novo synthesis post-synthetic treatment characterization thermal catalysis

PEPFL:A framework for a practical and efficient privacy-preserving federated learning

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Digital Communications and Networks 2024年第2期10卷 355-368页

作者： Yange Chen Baocang Wang Hang Jiang Pu Duan Yuan Ping zhiyong Hong State Key Laboratory of Integrated Service Networks Xidian UniversityXi'an710071China School of Information Engineering Xuchang UniversityXuchang461000China School of Telecommunications Engineering Xidian UniversityXi'an710071China Secure Collaborative Intelligence Laboratory Ant GroupHangzhou310000China Facility of Intelligence Manufacture Wuyi UniversityJiangmen529020China

As an emerging joint learning model,federated learning is a promising way to combine model parameters of different users for training and inference without collecting users’original ***,a practical and efficient solution has not been established in previous work due to the absence of efficient matrix computation and cryptography schemes in the privacy-preserving federated learning model,especially in partially homomorphic *** this paper,we propose a Practical and Efficient Privacy-preserving Federated Learning(PEPFL)***,we present a lifted distributed ElGamal cryptosystem for federated learning,which can solve the multi-key problem in federated ***,we develop a Practical Partially single Instruction Multiple Data(PsiMD)parallelism scheme that can encode a plaintext matrix into single plaintext for encryption,improving the encryption efficiency and reducing the communication cost in partially homomorphic *** addition,based on the Convolutional Neural Network(CNN)and the designed cryptosystem,a novel privacy-preserving federated learning framework is designed by using Momentum Gradient Descent(MGD).Finally,we evaluate the security and performance of *** experiment results demonstrate that the scheme is practicable,effective,and secure with low communication and computation costs.

关键词： Federated learning Partially single instruction multiple data Momentum gradient descent ElGamal Multi-key Homomorphic encryption

A novel subset assignment and matching method for DIC measurement of complex deformation in aircraft braking process

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Chinese Journal of Aeronautics 2024年第8期37卷 373-387页

作者： Xin SHI Xiang GUO Tao SUO Yingtao YUAN Hongli HE zhiyong REN School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China International Research Laboratory of Impact Dynamics and its Engineering Application Xi’an 710072China Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China Chinese Flight Test Establishment Xi’an 710089China

This paper proposes a measurement method related to the braking deformation of a complex *** the braking process,the deformation of the wheel includes large amounts of movement,vibration,warping,and distortion.A novel subset assignment and correlation method is proposed to measure the complex *** proposed method can greatly improve the accuracy and stability of the calculation of complex deformations by simplifying the complex deformation into translational deformations in logarithmic coordinate *** to the simulation and actual experiments,the proposed method can be utilized to measure the deformations of up to 100%tensile strain under complex *** to the accuracy verification experiment,the error of the proposed method is less than 50 *** results show that the proposed method can effectively carry out structural deformation measurement in the complex motion and deformation *** proposed method has great significance for structural performance analysis and optimization design considering complex motion and deformation.

关键词： Complex deformation Measurement Digital image correlation Aircraft braking Deformation field

Different Types of Bone Fractures Observed by Terahertz Time-Domain Spectroscopy

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Acta Mechanica Solida sinica 2024年第3期37卷 468-477页

作者： Minghao Zhang Xianjia Meng zhiyong Wang Chuanyong Qu Chuan Qu Donghui Fu Department of Mechanics Tianjin UniversityTianjin300072China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin300072China

Microcracks are common in compact bone,but their continued propagation can lead to macroscopic *** microcracks cannot be visualized radiographically,necessitating alternative noninvasive methods to identify excessive microcracking and prevent *** this study,terahertz time-domain spectroscopy(THz-TDS)was used to examine bone interiors near cracks resulting from loading in bovine tibia *** loading configurations,such as impact,quasi-static loading,and fatigue loading,known to induce different types of micro-scale damage,were *** values of refractive index and absorption coefficient of the bone samples were then determined from the THz-TDS spectra acquired before loading and after *** study revealed that different loading configurations led to varying terahertz optical coefficients associated with various types of bone ***,the refractive index notably increased under fatigue loading but remained relatively stable during quasi-static *** absorption coefficient of bone decreased only under fatigue ***,samples were subjected to axial and radial impacts without sustaining *** indicated that in the undamaged state,the change in refractive index was smaller compared to after impact failure,while the change in absorption coefficient remained consistent after *** radial impact loading,changes in refractive index and absorption coefficient were significantly more pronounced than under axial *** to loading,the measured value of refractive index was 2.72±0.11,and the absorption coefficient was 6.33±0.09 mm^(−1)at 0.5 THz.

关键词： Terahertz time-domain spectroscopy Bone Microdamage Noninvasive method

Tailoring the surface and interface structures of photocatalysts to enhance hydrogen production

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Science China Chemistry 2024年第4期67卷 1161-1174页

作者： Tao Zhang Pengfei Wang Shuai Yue Fei Li zhiyong Zhao sihui Zhan MOE Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Key Laboratory of Environmental Remediation and Pollution Control College of Environmental Science and EngineeringNankai UniversityTianjin 300350China

Photocatalytic water splitting using semiconductor photocatalysts is a promising approach for the production of carbon-neutral,sustainable and clean hydrogen ***,the separation and transport of photoinduced carriers are generally considered to be rate-limiting steps,and their low efficiency remains a major ***,much effort has been devoted to developing new strategies in surface/interface engineering of photocatalysts to improve the dynamics of charge separation/*** feature article briefly summarizes recent advances in photocatalyst surface/interface engineering by our research group,which have been achieved through the design of various novel photocatalysts,including interfacial modulation,heterostructure construction,heteroatom doping,single atom and diatom *** article is divided into three parts:first,we briefly introduce the three key processes involved in solar water splitting and reveal relationships between the properties of nanostructural photocatalysts and the fundamentals of water splitting;second,we detail methods and strategies for surface and interfacial structures to improve the efficiency of the fundamental processes,especially charge separation;finally,we explore prospects for photocatalytic water splitting *** article provides a valuable resource and strategies for researchers currently working in the field of photocatalytic water splitting.

关键词： photocatalytic water splitting surface/interface structures dual-functional photocatalysis

Route selection for opportunity-sensing and prediction of waterlogging

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Frontiers of Computer Science 2024年第4期18卷 147-159页

作者： Jingbin WANG Weijie ZHANG zhiyong YU Fangwan HUANG Weiping ZHU Longbiao CHEN College of Computer and Data Science Fuzhou UniversityFuzhou 350108China Department of Computer Science and Technology Xiamen UniversityXiamen 361005China

Accurate monitoring of urban waterlogging contributes to the city’s normal operation and the safety of residents’daily ***,due to feedback delays or high costs,existing methods make large-scale,fine-grained waterlogging monitoring impossible.A common method is to forecast the city’s global waterlogging status using its partial waterlogging *** method has two challenges:first,existing predictive algorithms are either driven by knowledge or data alone;and second,the partial waterlogging data is not collected selectively,resulting in poor *** overcome the aforementioned challenges,this paper proposes a framework for large-scale and fine-grained spatiotemporal waterlogging monitoring based on the opportunistic sensing of limited bus *** framework follows the Sparse Crowdsensing and mainly comprises a pair of iterative predictor and *** predictor uses the collected waterlogging status and the predicted status of the uncollected area to train the graph convolutional neural *** combines both knowledge-driven and data-driven approaches and can be used to forecast waterlogging status in all regions for the upcoming *** selector consists of a two-stage selection procedure that can select valuable bus routes while satisfying budget *** experimental results on real waterlogging and bus routes in Shenzhen show that the proposed framework could easily perform urban waterlogging monitoring with low cost,high accuracy,wide coverage,and fine granularity.

关键词： waterlogging prediction sparse crowdsensing active learning route selection graph convolutional network

Direct enantioselective reduction of C=C bond of β-polyfluoro-alkylated enones via asymmetric photoredox catalysis

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Science China Chemistry 2024年第6期67卷 2016-2021页

作者： Linghong Zhang Jin Ma Xu Ban Xiaowei Zhao Yanli Yin zhiyong Jiang Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province Henan UniversityKaifeng475004China School of Chemistry and Chemical Engineering Henan Normal UniversityPingyuan LaboratoryXinxiang453007China College of Advanced Interdisciplinary Science and Technology Henan University of TechnologyZhengzhou450001China

Direct enantioselective reduction of the C=C bond ofβ-polyfluoro-alkylated enones is an important but long-pending subject in asymmetric ***,we report on the viability of visible light-driven cooperative photoredox and chiral hydrogenbonding catalysis to effectively address this challenge,as a variety of products are obtained in high yields(up to 85%)with good to excellent enantioselectivities(up to 98%ee).The formation of thermodynamically favorable enol intermediates after double single-electron reduction represents the center of the ***,the utility of the current method is validated by the convenient regio-specific and-diverse synthesis of various deuterated derivatives for these products using inexpensive D_(2)O as the deuterium source.

关键词： photoredox catalysis Br?nsted acids asymmetric reduction enantioselective protonation azaarenes

Robotic compliant assembly for complex-shaped composite aircraft frame based on Gaussian process considering uncertainties

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Chinese Journal of Aeronautics 2024年第10期37卷 471-482页

作者： Yingke YANG Dongsheng LI Yunong ZHAI Jie WANG Lei XUE zhiyong YANG School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 3158002China COMAC Shanghai Aircraft Manufacturing Co. Ltd.Shanghai 201324China

Robots are finding increasing application in aircraft composite structure assembly due to their flexibility and the growing demand of aircraft manufacturers for high production *** contact force of the composite frame in a robotic assembly of the aircraft composite fuselage panel can hardly be controlled due to the multi-surface variable contact stiffness caused by compliance and complex shape with multiple mating *** paper proposes a robotic assembly system for the aircraft composite fuselage frame with a compliant contact force control strategy using the Gaussian process surrogate ***,a robotic assembly system is introduced,and the global coordinate system transformation model is ***,a compliant force control architecture is designed to generate the desired output ***,a Gaussian process surrogate model with uncertainties is utilized to model the complicated relationship between the robot’s output force and the normal contact force acting on the mating surface of the composite ***,an optimal contact force control strategy is implemented to improve the contact ***,an experiment demonstrates that the proposed methodology can ensure that the contact force on each surface is within the limit of the engineering specification and uniformly distributed,improving the quality compared to the traditional assembly process.

关键词： Aircraft Composite structure assembly Multi-surface contact Compliant control Gaussian process Uncertainty

Steric hindrance shielding viologen against alkali attack in realizing ultrastable aqueous flow batteries

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Journal of Energy Chemistry 2024年第10期97卷 529-534,I0011页

作者： Liwen Wang Kai Wan Xianzhi Yuan Zhipeng Xiang zhiyong Fu Zhenxing Liang Guangdong Provincial Key Laboratory of Fuel Cell Technology School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510641GuangdongChina State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510641GuangdongChina Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Jieyang 522000GuangdongChina

Viologens known as a kind of promising negolyte materials for aqueous organic redox flow batteries,face a critical stability challenge due to the S_N2 nucleophilic attack by hydroxide ions(OH-)during the battery *** this work,a N-cyclic quaternary ammonium-grafted viologen molecule,viz.1,1'-bis(4,4'-dime thylpiperidiniumyl)-4,4'-bipyridinium tetrachloride((DBPPy)Cl_(4)),is developed by the molecular engineering *** obtained(DBPPy)Cl_(4) molecule shows a decent solubility of 1.84 M and a redox potential of-0.52 V ***/AgCl,Experimental and theoretical results reveal that the grafted N-cyclic quaternary ammonium groups act as the steric hindrance to prevent nucleophilic attack by OH~-,increasing the alkali resistance of the electroactive *** symmetrical battery with 0.50 M(DBPPy)Cl4shows negligible decay during the 13-day cycling *** demonstration,the flow battery utilizing 1.0 M(DBPPy)Cl_(4) as the negolyte and 1-(1-oxyl-2,2',6,6'-tetramethylpiperidin-4-yl)-1'-(3-(trimethylammonio)propyl)-4,4'-bipyridinium trichloride as the posolyte exhibits a high capacity retention rate of 99.99%per cycle at 60 mA cm^(-2).

关键词： Aqueous organic flow batteries Viologen Stability Steric hindrance Alkali resistance