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Rare Metals 2024年第11期 5652-5663页

作者： Yang liu Ke Tan sen liu Xu Zhang Mao-Qiang Shen xue-sen liu Xin-Yue Gao Lin-Rui Hou Chang-Zhou Yuan School of Materials Science & Engineering University of Jinan

The shuttling diffusion of polysulfides is a bottleneck that seriously limits the performance of Li-S *** construction of sulfur cathodes with reliable trapping ability of polysulfides is the key to overcome such ***,a hierarchical porous architecture,i.e.,Co（OH）2sheets bonded Ti3C2TxMXene aerogel(Co（OH）2/MXA),is constructed via a facile selfassembled approach and used as an efficient free-standing polysulfides *** interconnected three-dimensional（3D） porous network with void space and strong interfacial interaction not only enables high sulfur loading but facilitates fast ion and electron *** and theoretical results confirm the hetero-framework exhibits outstanding immobilization and conversion ability for polysulfides due to its polar surface and bifunctional catalytic activities toward both formation and decomposition of *** optimized Co（OH）2/MXA cathode delivers excellent rate capability(407 mAh·g-1at 5C) with a sulfur loading of 2.7 mg·cm-2,and ultra-stable cycling performance as an extremely small capacity decay of～0.005% per cycle within 1700 cycles at 1C is achieved with a high sulfur loading of 6.7 mg·*** significantly,our design structural/componential methodology here promises the MXene-based aerogel electrodes for LiS batteries and beyond.

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Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

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Journal of Iron and Steel Research International 2024年第6期31卷 1344-1354页

作者： Peng-bo liu Shu-sen Cheng Yu-qing xue Xiao-man Cheng Zhao liu University of Science and Technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

Cooperative Covert Communication in Multi-Antenna Broadcast Channels

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China Communications 2024年第6期21卷 246-260页

作者： Qiao sen liu Guangjie Ji Xiaopeng liu Weiwei School of Electrical and Information Engineering Nanjing University of Information Science and TechnologyNanjing 210044China School of Automation Nanjing University of Science and TechnologyNanjing 210094China

With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become ***,this study aims to investigate the wireless covert communication in the two-user cooperative multi-antenna broadcast *** focus on the issue that the deteriorated reliability and undetectability are mainly affected by the transmission *** tackle this issue,we design a scheme based on beamforming to increase the reliability and undetectability of wireless covert communication in the multi-antenna broadcast *** first modeled and analyzed the cooperative multi-antenna broadcasting system,and put forward the target *** we use the SCA(successive convex approximation)algorithm to transform the target problem into a series of convex *** the convex problems are solved and the covert channel capacity is *** order to verify the effectiveness of the scheme,we conducted simulation *** simulation results show that the proposed beamforming scheme can effectively improve the reliability and undetectability of covert communication in multi-antenna broadcast channels.

关键词： beamforming covert communication multi-antenna broadcast channels OFDM

Evolution of pore systems in low-maturity oil shales during thermal upgrading--Quantified by dynamic SEM and machine learning

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Petroleum Science 2024年第3期21卷 1739-1750页

作者： Jun liu xue Bai Derek Elsworth Key Laboratory of Deep Underground Science and Engineering(Ministry of Education) Institute of New Energy and Low-Carbon TechnologySichuan UniversityChengdu610065SichuanChina International Quantum Academy Shenzhen518048GuangdongChina Shenzhen Institute of Advanced Electronic Materials Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055GuangdongChina Department of Energy and Mineral Engineering Pennsylvania State University ParkPA 16802USA

In-situ upgrading by heating is feasible for low-maturity shale oil,where the pore space dynamically *** characterize this response for a heated substrate concurrently imaged by *** systematically follow the evolution of pore quantity,size(length,width and cross-sectional area),orientation,shape(aspect ratio,roundness and solidity)and their anisotropy—interpreted by machine *** indicate that heating generates new pores in both organic matter and inorganic ***,the newly formed pores are smaller than the original pores and thus reduce average lengths and widths of the bedding-parallel pore ***,the average pore lengths and widths are increased in the bedding-perpendicular ***,heating increases the cross-sectional area of pores in low-maturity oil shales,where this growth tendency fluctuates at300℃.In addition,the orientation and shape of the newly-formed heating-induced pores follow the habit of the original pores and follow the initial probability distributions of pore orientation and ***,limited anisotropy is detected in pore direction and shape,indicating similar modes of evolution both bedding-parallel and *** propose a straightforward but robust model to describe evolution of pore system in low-maturity oil shales during heating.

关键词： Low-maturity oil shale Pore elongation Organic matter pyrolysis In-situthermal upgrading Scanning electron microscopy(SEM) Machine learning

Unsupervised social network embedding via adaptive specific mappings

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Frontiers of Computer Science 2024年第3期18卷 61-71页

作者： Youming GE Cong HUANG Yubao liu sen ZHANG Weiyang KONG School of Computer Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275China Guangdong Key Laboratory of Big Data Analysis and Processing Guangzhou 510006China

In this paper,we address the problem of unsuperised social network embedding,which aims to embed network nodes,including node attributes,into a latent low dimensional *** recent methods,the fusion mechanism of node attributes and network structure has been proposed for the problem and achieved impressive prediction ***,the non-linear property of node attributes and network structure is not efficiently fused in existing methods,which is potentially helpful in learning a better network *** this end,in this paper,we propose a novel model called ASM(Adaptive Specific Mapping)based on encoder-decoder *** encoder,we use the kernel mapping to capture the non-linear property of both node attributes and network *** particular,we adopt two feature mapping functions,namely an untrainable function for node attributes and a trainable function for network *** the mapping functions,we obtain the low dimensional feature vectors for node attributes and network structure,***,we design an attention layer to combine the learning of both feature vectors and adaptively learn the node *** encoder,we adopt the component of reconstruction for the training process of learning node attributes and network *** conducted a set of experiments on seven real-world social network *** experimental results verify the effectiveness and efficiency of our method in comparison with state-of-the-art baselines.

关键词： network embedding specific kernel mapping attention mechanism

An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi liu xue-Dong Li Liang Cheng Li liu Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements,which provides efficient methods for the preparation of axially chiral ***,developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination *** this work,we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent *** addition,the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis *** methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%)and excellent central-to-axial chirality conversion(up to 99%conversion percentage).This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： br?nsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

Peeling of Magneto-responsive Beams with Large Deformation Mediated by the Parallel Magnetic Field

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Acta Mechanica Solida Sinica 2024年第3期37卷 457-467页

作者： Gongqi Cao Zhangna xue Shiyang liu Yuchen Jin Jianlin liu College of Pipeline and Civil Engineering China University of Petroleum(East China)Qingdao266580China

Elasto-capillarity phenomena are prevalent in various industrial fields such as mechanical engineering,material science,aerospace,soft robotics,and *** this study,two typical peeling processes of slender beams driven by the parallel magnetic field are investigated based on experimental and theoretical *** first is the adhesion of two parallel beams,and the second is the self-folding of a long *** these two cases,the energy variation method on the elastica is used,and then,the governing equations and transversality boundary conditions are *** is shown that the analytical solutions are in excellent agreement with the experimental *** effects of magnetic induction intensity,distance,and surface tension on the deflection curve and peeling length of the elastica are fully *** results are instrumental in accurately regulating elasto-capillarity in structures and provide insights for the engineering design of programmable microstructures on surfaces,microsensors,and bionic robots.

关键词： Magneto-responsive beam Adhesion and peeling Self-folding Elastica Transversality condition

Structural Engineering of Hierarchical Magnetic/Carbon Nanocomposites via In Situ Growth for High-Efficient Electromagnetic Wave Absorption

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Nano-Micro Letters 2024年第9期16卷 262-278页

作者： Xianyuan liu Jinman Zhou Ying xue Xianyong Lu Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

Materials exhibiting high-performance electromagnetic wave absorption have garnered considerable scientific and technological attention,yet encounter significant *** new materials and innovative structural design concepts is crucial for expanding the application field of electromagnetic wave ***,hierarchical structure engineering has emerged as a promising approach to enhance the physical and chemical properties of materials,providing immense potential for creating versatile electromagnetic wave absorption ***,an exceptional multi-dimensional hierarchical structure was meticulously devised,unleashing the full microwave attenuation capabilities through in situ growth,selfreduction,and multi-heterogeneous interface *** hierarchical structure features a three-dimensional carbon framework,where magnetic nanoparticles grow in situ on the carbon skeleton,creating a necklace-like ***,magnetic nanosheets assemble within this *** impedance matching was achieved by precisely adjusting component proportions,and intelligent integration of diverse interfaces bolstered dielectric *** obtain Fe_(3)O_(4)-Fe nanoparticles/carbon nanofibers/Al-Fe_(3)O_(4)-Fe nanosheets composites demonstrated outstanding performance with a minimum reflection loss(RLmin)value of−59.3 dB and an effective absorption bandwidth(RL≤−10 dB)extending up to 5.6 GHz at 2.2 *** notable accomplishments offer fresh insights into the precision design of high-efficient electromagnetic wave absorption materials.

关键词： Electromagnetic wave absorption Hierarchical structure In situ growth Self-reduction

Fast Cross-Platform Binary Code Similarity Detection Framework Based on CFGs Taking Advantage of NLP and Inductive GNN

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Chinese Journal of Electronics 2024年第1期33卷 128-138页

作者： Jinxue PENG Yong WANG Jingfeng xue Zhenyan liu School of Computer Science and Technology Beijing Institute of Technology

Cross-platform binary code similarity detection aims at detecting whether two or more pieces of binary code are similar or not. Existing approaches that combine control flow graphs(CFGs)-based function representation and graph convolutional network(GCN)-based similarity analysis are the best-performing ones. Due to a large amount of convolutional computation and the loss of structural information, the use of convolution networks will inevitably bring problems such as high overhead and sometimes inaccuracy. To address these issues, we propose a fast cross-platform binary code similarity detection framework that takes advantage of natural language processing(NLP)and inductive graph neural network(GNN) for basic blocks embedding and function representation respectively by simulating extracting structural features and temporal features. GNN’s node-centric and small batch is a suitable training way for large CFGs, it can greatly reduce computational overhead. Various NLP basic block embedding models and GNNs are evaluated. Experimental results show that the scheme with long short term memory(LSTM)for basic blocks embedding and inductive learning-based Graph SAGE(GAE) for function representation outperforms the state-of-the-art works. In our framework, we can take only 45% overhead. Improve efficiency significantly with a small performance trade-off.

关键词： Training Semantics Process control Binary codes Feature extraction Natural language processing Graph neural networks

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Vision-based docking system for an aromatic-hydrocarbon-inspired reconfigurable robot

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Science China(Technological Sciences) 2024年第6期67卷 1798-1816页

作者： XING FangYi XU Cheng liu JinGuo xue ZhiHui State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China School of Automation and Electrical Engineering Shenyang Ligong UniversityShenyang110158China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang110169China University of Chinese Academy of Sciences Beijing100049China

Aromatic hydrocarbons generally refer to compounds containing benzene *** types of isomers can be formed by replacing hydrogen atoms on the benzene *** this paper,an aromatic-hydrocarbon-inspired modular robot(AHIMR)is *** robot can be reassembled into different configurations suitable for various task requirements.A vision-based docking system is designed for the *** system primarily consists of two stages:a remote guidance stage and a precise docking *** the remote guidance stage,an object module is identified using an illumination adaptive target recognition algorithm,and then the active module moves to the docking area through communication with *** the precise docking stage,the active module calculates the relative pose with the object module using a perspective-n-point method and dynamically adjusts its posture to *** this process,a Kalman filter is used to reduce target occlusion and jitter *** addition,the docking system feasibility is verified via several simulation *** module docking accuracy is controlled within 0.01 m,which meets the reconfiguration task requirements of the *** the AHIMR submodule docking experiment,the active module accurately moves to the expected position with a docking success rate of 95%.

关键词： modular robot reconfiguration aromatic hydrocarbon autonomous docking visual identification