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Lithium sulfur Batteries:Insights from solvation Chemistry to Feasibility Designing strategies for Practical Applications

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Energy & Environmental Materials 2024年第4期7卷 5-27页

作者： jian Tan Longli Ma Yuan Wang Pengshu Yi Chuming ye Zhan Fang Zhiheng Li Mingxin ye jianfeng shen Institute of special Materials and Technology Fudan University Department of Materials science Fudan University Department of Chemistry Fudan University

Rechargeable lithium-sulfur (Li-s) batteries,featuring high energy density,low cost,and environmental friendliness,have been dubbed as one of the most promising candidates to replace current commercial rechargeable Li-ion ***,their practical deployment has long been plagued by the infamous"shuttle effect"of soluble Li polysulfides (LiPss) and the rampant growth of Li dendrites.

关键词： characterization tools design strategies Li–s batteries practical applications solvation chemistry

Complicated target recognition by archaeal box C/D guide RNAs

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science China(Life sciences) 2024年第4期67卷 631-644页

作者： jiayin Wang songlin Wu Keqiong ye Key Laboratory of RNA science and Engineering CAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China

Box C/D RNAs guide the site-specific formation of 2′-O-methylated nucleotides(Nm)of RNAs in eukaryotes and *** C/D RNAs have been profiled in several archaea,their targets have not been experimentally ***,we mapped Nm in r RNAs,t RNAs,and abundant small RNAs(s RNAs)and profiled C/D RNAs in the crenarchaeon sulfolobus *** targets of C/D RNAs were assigned by analysis of base-pairing interactions,in vitro modification assays,and gene deletion experiments,revealing a complicated landscape of C/D RNA-target interactions.C/D RNAs widely use dual antisense elements to target adjacent sites in r RNAs,enhancing modification at weakly bound *** consecutive sites can be guided with the same antisense element upstream of box D or D′,a phenomenon known as doublespecificity that is exclusive to internal box D′in eukaryotic C/D *** C/D RNAs guide modification at a single non-canonical *** study reveals the global landscape of RNA-guided 2′-O-methylation in an archaeon and unexpected targeting rules employed by C/D RNA.

关键词： C/D RNA 2′-O-methylation archaea guide RNA RNA modification

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Design and experimental research on the sweet potato seedling transplanting mechanism of the planetary gear train with deformed elliptical gear transmission

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International journal of Agricultural and Biological Engineering 2024年第3期17卷 91-99页

作者： Bingliang ye Yuxuan ye Haili Zhou Gaohong Yu Xiong Zhao Bin Deng Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Zhejiang Province Key Laboratory of Transplanting Equipment and Technology Hangzhou 310018China Key Laboratory of Agricultural Equipment for Hilly and Mountainous Areas in southeastern China(Co-construction by Ministry and Province) Ministry of Agriculture and Rural AffairsHangzhou 310018China

Aiming at the lack of suitable machines for sweet potato seedling transplanting in China,and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling,a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical *** working principle of the transplanting mechanism was analyzed,and the kinematics modeling and analysis of the mechanism were carried *** study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting *** parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting *** on the optimized parameters,the structure of the transplanting mechanism was designed,and a virtual prototype of the mechanism was created,whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the *** high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism’s kinematic characteristics and transplanting *** test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory,meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling;And when the rotary speed of the mechanism are 20 r/min and 30 r/min,the average success ratios of sweet potato seedlings transplanting are 90%and 82%,respectively,which prove the application feasibility of the mechanism in the practical machines.

关键词： sweet potato seedling transplanter transplanting mechanism deformed elliptical gear transmission kinematics analysis membership function optimization design

Learning Epipolar Line Window Attention for stereo Image super-Resolution Reconstruction

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Computers, Materials & Continua 2024年第2期78卷 2847-2864页

作者： Xue Li Hongying Zhang Zixun ye Xiaoru Huang school of Information Engineering Southwest University of Science and TechnologyMianyang621010China

Transformer-based stereo image super-resolution reconstruction(stereo sR)methods have significantly improved image ***,existing methods have deficiencies in paying attention to detailed features and do not consider the offset of pixels along the epipolar lines in complementary views when integrating stereo *** address these challenges,this paper introduces a novel epipolar line window attention stereo image super-resolution network(EWAssR).For detail feature restoration,we design a feature extractor based on Transformer and convolutional neural network(CNN),which consists of(shifted)window-based self-attention((s)W-MsA)and feature distillation and enhancement blocks(FDEB).This combination effectively solves the problem of global image perception and local feature attention and captures more discriminative high-frequency features of the ***,to address the problem of offset of complementary pixels in stereo images,we propose an epipolar line window attention(EWA)mechanism,which divides windows along the epipolar direction to promote efficient matching of shifted pixels,even in pixel smooth *** accurate pixel matching can be achieved using adjacent pixels in the window as a *** experiments demonstrate that our EWAssR can reconstruct more realistic detailed *** quantitative results show that in the experimental results of our EWAssR on the Middlebury and Flickr1024 data sets for 2×sR,compared with the recent network,the Peak signal-to-noise ratio(PsNR)increased by 0.37 dB and 0.34 dB,respectively.

关键词： stereo sR epipolar line window attention feature distillation

Effect of(Cr,V)_(2)(C,N)on the Microstructure and Mechanical Properties of WC-10Co Cemented Carbides

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journal of Wuhan University of Technology(Materials science) 2024年第5期39卷 1138-1148页

作者： LI Xiangkun WANG Lu ye jinwen school of Materials science and Engineering Sichuan UniversityChengdu 610065China

WC-10Co cemented carbides with finer WC and narrower grain size distributions are produced by using(Cr,V)_(2)(C,N)as grain growth *** a result,with the increase of(Cr_(0.9),V_(0.1))_(2)(C,N)and(V_(0.9),Cr_(0.1))_(2)(C,N),the grains size of WC and mean free path of Co phase decrease,and adjacency of WC *** and homogenization of grains enhance the transverse rupture strength(TRs)and the ***,the deflection and bridging of cracks keep the fracture toughness at a respectable *** WC-10Co-0.6(Cr_(0.9),V_(0.1))_(2)(C,N)-0.025(V_(0.9),Cr_(0.1))_(2)(C,N)cemented carbides exhibit excellent comprehensive mechanical properties with the TRs of 4602.6 MPa,hardness of 1835 kg/mm^(2),and fracture toughness of 10.39 MPa·m^(1/2),***,the large pores are caused by excess N larger than 0.03 wt%and deteriorates the mechanical *** provide a new approach to WC-Co cemented carbides preparation with a narrow grain size distribution by adding novel grain growth inhibitors.

关键词： (Cr,V)_(2)(C,N) nutrient content WC grains size microstructure mechanical properties

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Clifford Deformations of Koszul Frobenius Algebras and Noncommutative Quadrics

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Algebra Colloquium 2024年第1期31卷 63-82页

作者： jiwei He Yu ye Department of Mathematics Hangzhou Normal UniversityHangzhou 311121China school of Mathematical sciences University of Science and Technology of China Hefei 230026China

A Clifford deformation of a Koszul Frobenius algebra E is a finite dimensional Z_(2)-graded algebra E(θ),which corresponds to a noncommutative quadric hypersurface E^(!)/(z)for some central regular element z∈E_(2)^(!).It turns out that the bounded derived category D^(b)(gr_(Z_(2))E(θ))is equivalent to the stable category of the maximal Cohen-Macaulay modules over E^(!)/(z)provided that E!is *** a consequence,E^(!)/(z)is a noncommutative isolated singularity if and only if the corresponding Clifford deformation E(θ)is a semisimple Z_(2)-graded *** preceding equivalence of triangulated categories also indicates that Clifford deformations of trivial extensions of a Koszul Frobenius algebra are related to Knörrer's periodicity theorem for quadric *** an application,we recover Knörrer's periodicity theorem without using matrix factorizations.

关键词： Koszul Frobenius algebra Clifford deformation noncommutative quadric hypersurface maximal Cohen-Macaulay module

Cholesky GAs models for large time-varying covariance matrices

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journal of Management science and Engineering 2024年第1期9卷 115-142页

作者： Tingguo Zheng shiqi ye Department of statistics and Data science School of EconomicsXiamen UniversityXiamen361005China Wang Yanan Institute for studies in Economics Xiamen UniversityXiamen361005China Paula and Gregory Chow Institute for studies in Economics Xiamen UniversityXiamen361005China

This paper develops a new class of multivariate models for large-dimensional time-varying covariance matrices,called Cholesky generalized autoregressive score(GAs)models,which are based on the Cholesky decomposition of the covariance matrix and assume that the parameters are ***,two types of score-driven updates are considered:one is closer to the GARCH family,and the other is inspired by the stochastic volatility *** demonstrate that the models can be estimated equation-wise and are computationally feasible for high-dimensional ***,we design an equationwise dynamic model averaging or selection algorithm which simultaneously extracts model and parameter uncertainties,equipped with dynamically estimated model *** simulation results illustrate the superiority of the proposed ***,using a sizeable daily return dataset that includes 124 sectors in the Chinese stock market,two empirical studies with a small sample and a full sample are conducted to verify the advantages of our *** full sample analysis by a dynamic correlation network documents significant structural changes in the Chinese stock market before and after COVID-19.

关键词： Cholesky decomposition GAs Dynamic conditional correlations Dynamic model averaging

strong Antiferromagnetic Exchange-Coupling Observed in Hydride-Bridged Dimeric Dysprosium(Ⅲ)single-Molecule Magnet

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Chinese journal of Chemistry 2024年第4期42卷 391-396页

作者： Qian-Cheng Luo Ke-Xin Yu Peng-Bo jin ye-ye Liu Yuan-Qi Zhai Yan-Zhen Zheng Frontier Institute of science and Technology State Key Laboratory of Electrical Insulation and Power EquipmentXi'an Key Laboratory of Electronic Devices and Materials ChemistrySchool of Chemistry and School of PhysicsXi'an Jiaotong University99 Yanxiang RoadXi'anShaanxi710054 China

One dihydride-bridged dimeric Dy(Ⅲ)guanidinate complex,formulated as[{(Me_(3)si)_(2)NC(NiPr)_(2)}_(2)Dy(μ-H)]_(2)(1Dy),was successfully isolated and the introduction of hydride bridges significantly reduces the intramolecular Dy(Ⅲ)…Dy(Ⅲ)distance to only 3.688(1)Å.To investigate the effect of such a short Dy(Ⅲ)…Dy(Ⅲ)distance on magnetism,we also prepared its dibromide-bridged analogue[{(Me_(3)si)_(2)NC(NiPr)_(2)}_(2)Dy(μ-Br)]_(2)(2Dy),which has a much longer Dy(Ⅲ)…Dy(Ⅲ)distance of 4.605(4)Å.surprisingly,2Dy demonstrates much larger effective energy barrier for magnetization reversal(U_(eff))and higher blocking temperature(T_(B)).The worse performance of 1Dy is attributed to the concerted effect of strong antiferromagnetic interactions between Dy(Ⅲ)ions(j_(total)=–2.683 cm^(–1))and the unparallel arrangement of magnetic principle axes of the Dy(Ⅲ)ions for 1Dy.

关键词： single-molecule magnets Lanthanides Guanidinate ligand Hydride bridge Magnetic properties Ab initio calculations

The Immense Impact of Reverse Edges on Large Hierarchical Networks

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Engineering 2024年第5期36卷 240-249页

作者： Haosen Cao Bin-Bin Hu Xiaoyu Mo Duxin Chen jianxi Gao ye Yuan Guanrong Chen Tamás Vicsek Xiaohong Guan Hai-Tao Zhang MOE Engineering Research Center of Autonomous Intelligent Unmanned systems State Key Laboratory of Intelligent Manufacturing Equipment and TechnologySchool of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhan 430074China school of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore jiangsu Key Laboratory of Networked Collective Intelligence School of MathematicsSoutheast UniversityNanjing 210096China Department of Computer science Rensselaer Polytechnic InstituteTroyNY 12180USA Department of Electronic Engineering City University of Hong KongHong Kong 999077China Department of Biological Physics Eötvös UniversityBudapest 1117Hungary MOE Key Laboratory for Intelligent Networks and Network security School of Automation Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China

Hierarchical networks are frequently encountered in animal groups,gene networks,and artificial engineering systems such as multiple robots,unmanned vehicle systems,smart grids,wind farm networks,and so *** structure of a large directed hierarchical network is often strongly influenced by reverse edges from lower-to higher-level nodes,such as lagging birds’howl in a flock or the opinions of lowerlevel individuals feeding back to higher-level ones in a social *** study reveals that,for most large-scale real hierarchical networks,the majority of the reverse edges do not affect the synchronization process of the entire network;the synchronization process is influenced only by a small part of these reverse edges along specific *** surprisingly,a single effective reverse edge can slow down the synchronization of a huge hierarchical network by over 60%.The effect of such edges depends not on the network size but only on the average in-degree of the involved *** overwhelming majority of active reverse edges turn out to have some kind of“bunching”effect on the information flows of hierarchical networks,which slows down synchronization *** finding refines the current understanding of the role of reverse edges in many natural,social,and engineering hierarchical networks,which might be beneficial for precisely tuning the synchronization rhythms of these *** study also proposes an effective way to attack a hierarchical network by adding a malicious reverse edge to it and provides some guidance for protecting a network by screening out the specific small proportion of vulnerable nodes.

关键词： synchronizability Large hierarchical networks Reverse edges Information flows Complex networks