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Nano Research 2024年第9期17卷 8112-8118页

作者： zi-Jun Zou Shi-Yi Yin Yao tang Sheng-Liang Zhong Lei Wang Shi-long Xu Hai-Wei Liang College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Department of Chemistry University of Science and Technology of ChinaHefei 230026China School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China

Carbon-supported platinum-lanthanum(Pt-Ln)intermetallic compound(IMC)nanoparticles with high activity and robust stability have been demonstrated as promising cathode catalysts for proton-exchange membrane fuel ***,the preparation of Pt-Ln IMC catalysts needs high-temperature annealing treatment that inevitably causes nanoparticle sintering,resulting in significant reduction of the electrochemical surface area and mass-based ***,we prepare small-sized M-doped Pt_(5)Ce(M=Ga,Cd,and Sb)IMCs catalysts via a low-melting-point metal doping *** speculate that the doping of low-melting-point metals can facilitate the generation of vacancies in the crystal lattice through thermal activation and thus reduce the kinetic barriers for the formation of intermetallic Pt_(5)Ce *** prepared Ga-doped Pt_(5)Ce catalyst exhibits a higher electrochemical active surface area(81 m^(2)·gPt^(-1))and a larger mass activity(0.45 A·mgPt^(-1)at 0.9 V)over the undoped Pt_(5)Ce and commercial Pt/C *** the membrane electrode assembly test,the Ga-doped Pt_(5)Ce cathode delivers a power density of 0.98 W·cm^(-2)at 0.67 V,along with a voltage loss of only 27 mV at 0.8 A·cm^(-2)at the end of accelerated stability test.

关键词： P5Ce low-melting-point metal small-sized intermetallic compound catalysis fuel cells

Research,application and development of inorganic binder for casting process

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China Foundry 2024年第5期21卷 461-475页

作者： Xiao-long Gong Sheng-li Hu zi-tian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Inorganic binder used in casting process has the advantages of low odor,labor-friendly conditions,and relatively low cost,which is one of the main development directions for casting molding materials in the ***,compared to organic binders(such as resin binders),inorganic binders exhibit lower bonding strength and are more sensitive to environmental *** sensitivity poses challenges,particularly in the reclamation of used sand,thus limiting their broader *** this paper,the research and application status of inorganic binders(mainly silicate inorganic binders)and their curing methods are *** addition,the research and application of phosphate inorganic binders and 3D printing inorganic binders that are being developed are ***,a detailed comparative analysis is conducted on the challenging issue of“reclamation for used sand”in the application of inorganic ***,the development direction of inorganic binders is clarified.

关键词： inorganic binder silicate system phosphate system 3D printing used sand reclamation development trend

Carbon nanofibers embedded with Fe-Co alloy nanoparticles via electrospinning as lightweight high-performance electromagnetic wave absorbers

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Rare Metals 2024年第6期43卷 2769-2783页

作者： Wen-Jun Cai Jian-Guo Jiang zi-Dong Zhang zi-Xuan Liu Lu-JieZhang Zhen-Kun long Ke Bi Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Materials Science and Engineering Shandong UniversityJinan 250061China Energy Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

As a lot of electromagnetic pollution and interference issues have emerged,to overcome electromagnetic interference,prevent electromagnetic hazards,and develop new high-performance electromagnetic wave(EMW)absorbers have become a significant task in the field of materials *** this paper,a three-dimensional(3D)carbon nanofibers network with core-shell structure,embedded with varied molar ratios of iron and cobalt(4:0,3:1,2:2,1:3,0:4),was effectively synthesized(Fe/Co@C-CNFs)via *** phase,microstructure,magnetic and EMW absorption properties were *** is discovered that Fe/Co@C-CNFs doped with iron:cobalt=1:1 have excellent EMW absorption *** the matching thickness is 1.08 mm,the minimum reflection loss(RL)value is-18.66 dB,while the maximum effective absorption bandwidth(EAB)reaches 4.2 GHz(13.9-18 GHz)at a thickness of 1.22 *** is owing to the absorbers'superior impedance matching and multiple reflections as well as the conductivity,dielectric,and magnetic losses of carbon nanofibers embedded with Fe-Co alloy *** addition,the radar cross section(RCS)of the absorbers has been calculated by CST Studio Suite,showing that the absorbing coating can effectively reduce the RCS at various angles,especially for Fe/Co@C-CNFs doped with iron:cobalt=1:*** findings not only provide new insights for the preparation of light-weight and high-performance electromagnetic wave absorbers,but also contribute to energy storage and conversion.

关键词： Electromagnetic wave(EMW)absorbers Fe/Co@C-CNFs Core-shell structure EMW absorbing mechanism Radar cross section(RCS)

Hyperbolic tangent Function-Based Protocols for Global/Semi-Global Finite-Time Consensus of Multi-Agent Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1381-1397页

作者： Zongyu Zuo Jingchuan tang Ruiqi Ke Qing-long Han Seventh Research Division Beihang University(BUAA)Beijing 100191China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia IEEE

This paper investigates the problem of global/semi-global finite-time consensus for integrator-type multi-agent *** hyperbolic tangent function-based protocols are pro-posed to achieve global and semi-global finite-time consensus for both single-integrator and double-integrator multi-agent systems with leaderless undirected and leader-following directed commu-nication *** new protocols not only provide an explicit upper-bound estimate for the settling time,but also have a user-prescribed bounded control *** addition,compared to some existing results based on the saturation function,the pro-posed approach considerably simplifies the protocol design and the stability *** examples and an application demonstrate the effectiveness of the proposed protocols.

关键词： Consensus protocol finite-time consensus hyper-bolic tangent function multi-agent systems.

User Churn Prediction Hierarchical Model Based on Graph Attention Convolutional Neural Networks

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China Communications 2024年第7期21卷 169-185页

作者： Mei Miao tang Miao Zhou long School of Economics and Management Beijing Jiaotong UniversityBeijing 100044China School of Automotive and Rail Transit Nanjing Institute of TechnologyNanjing 211167China Nanjing Intelligent Aviation Research Institute Co. LtdNanjing 210014China

The telecommunications industry is becoming increasingly aware of potential subscriber churn as a result of the growing popularity of smartphones in the mobile Internet era,the quick development of telecommunications services,the implementation of the number portability policy,and the intensifying competition among *** the same time,users'consumption preferences and choices are *** churn prediction models must be created in order to accurately predict the churn tendency,since keeping existing customers is far less expensive than acquiring new *** conventional or learning-based algorithms can only go so far into a single subscriber's data;they cannot take into consideration changes in a subscriber's subscription and ignore the coupling and correlation between various ***,the current churn prediction models have a high computational burden,a fuzzy weight distribution,and significant resource economic *** prediction algorithms involving network models currently in use primarily take into account the private information shared between users with text and pictures,ignoring the reference value supplied by other users with the same *** work suggests a user churn prediction model based on Graph Attention Convolutional Neural Network(GAT-CNN)to address the aforementioned *** main contributions of this paper are as follows:Firstly,we present a three-tiered hierarchical cloud-edge cooperative framework that increases the volume of user feature input by means of two aggregations at the device,edge,and cloud ***,we extend the use of users'own data by introducing self-attention and graph convolution models to track the relative changes of both users and packages ***,we build an integrated offline-online system for churn prediction based on the strengths of the two models,and we experimentally validate the efficacy of cloudside collaborative training and *** summary,the churn

关键词： cloud-edge cooperative framework GAT-CNN self-attention and graph convolution models subscriber churn prediction

Inferring the spin distribution of binary black holes using deep learning

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Chinese Physics C 2024年第10期48卷 275-283页

作者： Li tang Xi-long Fan School of Math and Physics Mianyang Teachers'CollegeMianyang 621000China School of Physics and Technology Wuhan UniversityWuhan 430072 China

The spin characteristics of black holes offer valuable insights into the evolutionary pathways of their progenitor *** is crucial for understanding the broader population properties of black *** hierarchical Bayesian inference techniques employed to discern these properties often demand substantial time,and consensus regarding the spin distribution of binary black hole(BBH)systems remains *** this study,leveraging observations from GWTC-3,we adopted a machine learning approach to infer the spin distribution of black holes within BBH ***,we developed a deep neural network(DNN)and trained it using data generated from a Beta *** training strategy,involving the segregation of data into 10 bins,not only expedites model training but also enhances the versatility and adaptability of the DNN to accommodate the growing volume of gravitational wave *** Monte Carlo-bootstrap(MC-bootstrap)to generate observation-simulated samples,we derived spin distribution parameters:α=1.3_(-0.18)^(+0.25),β=1.70_(-0.29)^(+0.24)for the larger BH sample and α=1.37_(-0.20)^(+0.31),β=1.63_(-0.20)^(+0.30) for the smaller BH *** our constraints,the distributions of component spin magnitudes suggest the likelihood of both black holes in the BBH merger possessing non-zero spin.

关键词： gravitational wave black hole merges deep learning

Stodies on the Witting Reaction (Ⅹ Ⅹ Ⅻ) Phase Transfer Catalytic Bis-Witting Reaction of 1,2-and 1,3-Bisylide

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Chinese Chemical Letters 1997年第5期8卷 361-364页

作者： Wen Jing XIAO zi long tang Ming Wu DING Wen Fang HUANG(Insititute of Organic Synthesis, Central China Normal University, Wuhan430070)Tian Jie WU(Center of Analysis and Testing, Central China Normal University, Wuhan430070) Insititute of Organic Synthesis Central China Normal University Wuhan 430070 China Center of Analysis and Testing Central China Normal University Wuhan 430070 China

The phase transfer catalytic (PTC) bis-Wittig reaction between substitutedbenzaldehyde and 1,2- and 1,3-bisylides in the presence of K2Co3 was discussed.

关键词： HNMR MS Phase Transfer Catalytic Bis-Witting Reaction of 1,2-and 1,3-Bisylide Stodies on the Witting Reaction

Visual Semantic Segmentation Based on Few/Zero-Shot Learning:An Overview

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1106-1126页

作者： Wenqi Ren Yang tang Qiyu Sun Chaoqiang Zhao Qing-long Han Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China National Key Laboratory of Air-Based Information Perception and Fusion Aviation Industry Corporation of ChinaLuoyang 471000China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia

Visual semantic segmentation aims at separating a visual sample into diverse blocks with specific semantic attributes and identifying the category for each block,and it plays a crucial role in environmental *** learning-based visual semantic segmentation approaches count heavily on largescale training data with dense annotations and consistently fail to estimate accurate semantic labels for unseen *** obstruction spurs a craze for studying visual semantic segmentation with the assistance of few/zero-shot *** emergence and rapid progress of few/zero-shot visual semantic segmentation make it possible to learn unseen categories from a few labeled or even zero-labeled samples,which advances the extension to practical ***,this paper focuses on the recently published few/zero-shot visual semantic segmentation methods varying from 2D to 3D space and explores the commonalities and discrepancies of technical settlements under different segmentation ***,the preliminaries on few/zeroshot visual semantic segmentation,including the problem definitions,typical datasets,and technical remedies,are briefly reviewed and ***,three typical instantiations are involved to uncover the interactions of few/zero-shot learning with visual semantic segmentation,including image semantic segmentation,video object segmentation,and 3D ***,the future challenges of few/zero-shot visual semantic segmentation are discussed.

关键词： Visual segmentation separating

Exploring the Pathogenesis of Autoimmune Liver Diseases from the Heterogeneity of Target Cells

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Journal of Clinical and Translational Hepatology 2024年第7期12卷 659-666页

作者： zi-Xuan Qiu Lin-Xiang Huang Xiao-Xiao Wang zi-long Wang Xiao-He Li Bo Feng Peking University People’s Hospital Peking University Hepatology InstituteBeijing Key Laboratory of Hepatitis C and Immunotherapy for Liver DiseasesBeijing International Cooperation Base for Science and Technology on NAFLD DiagnosisBeijingChina

The incidence of autoimmune liver diseases(ALDs)and research on their pathogenesis are increasing ***,except for autoimmune hepatitis,which responds well to immunosuppression,primary biliary cholangitis and primary sclerosing cholangitis are insensitive to immunosuppressive *** the known effects of the environment,genetics,and immunity on ALDs,the heterogeneity of target cells provides new insights into their *** review started by exploring the heterogeneity in the development,structures,and functions of hepatocytes and epithelial cells of the small and large bile *** example,cytokeratin(CK)8 and CK18 are primarily expressed in hepatocytes,while CK7 and CK19 are primarily expressed in intrahepatic ***,emerging technologies of single-cell RNA sequencing and spatial transcriptomic are being applied to study *** review offered a new perspective on understanding the pathogenic mechanisms and potential treatment strategies for ALDs.

关键词： Autoimmune hepatitis Primary biliary cholangitis Primary sclerosing cholangitis Disease heterogeneity Single-cell RNA sequencing Pathogenesis

Synthesis of cyclic hexayne from Me3Si-/Ph2P(O)-protected ethyne by transition metal catalyzed coupling reactions

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Synthesis of cyclic hexayne from Me3Si-/Ph2P(O)-protected et...