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Nano Research 2024年第7期17卷 5914-5921页

作者： Chun-Ying Chen Qi-Jie Mo Fu-Zhen li Hai-li Song li Zhang MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

Hollow-structured all-silicon terahertz metasurface supporting quasi-bound states in the continuum for refractive index based Auramine O concentration sensing

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Photonics Research 2024年第7期12卷 1574-1582页

作者： XIN TANG HAODUO JIA LANBIN li MING li DAI WU KUI ZHOU PENG li WEIJUN WANG JITAO li DINGYU YANG College of Optoelectronic Engineering Chengdu University of Information TechnologyChengdu 610225China Institute of Applied Electronics China Academy of Engineering PhysicsMianyang 621000China School of Precision Instruments and Opto-Electronics Engineering Tianjin UniversityTianjin 300072China Guizhou Zhenhua Fengguang Semiconductor Co. Ltd.Guiyang 550000China Chengdu Huanyuxin Technology Co. Ltd.Chengdu 610095China

Quasi-bound states in the continuum (QBIC),with exceptionally high-Q factors and the local field enhancement effect,have found potential applications in matter *** the QBIC mechanism into terahertz(THz) metasurfaces can significantly enhance the interaction between incident THz waves and matter,providing a feasible platform for the detection of biochemical ***,most experimental studies on terahertz QBIC metasurfaces utilize metallic *** contrast,research on terahertz all-dielectric QBIC metasurfaces generally remains at the simulation stage due to the high fabrication process requirements,and transitioning to the experimental stage still poses many *** this paper,a hollow-structured all-silicon metasurface supporting THz QBIC is *** resonance of THz QBIC is excited via a simple hollow structure and observed in *** and experimental results demonstrated that the designed THz QBIC metasurface can achieve sensing of Auramine ***,it is the first study,to our knowledge,to employ a metasurface to sense Auramine ***,the sensing performance maintains good stability under different humidity and temperature *** study provides new references and insights for the design and implementation of THz QBIC,and also opens a new pathway for the detection of Auramine O.

关键词： supporting continuum refractive

Photoinduced Perfluoroalkyloximation of Alkenes with Simple Perfluoroalkyl Halides

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Chinese Journal of Chemistry 2024年第18期42卷 2217-2222页

作者： Wei li Zhongji li Deliang Zhong Nianxing Wang Huaifeng li State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxiNormalUniversityGuilinGuangxi541004China School of Chemistry and Pharmacy Qilu University of TechnologyJinanShandong 250353China

In this paper,the difunctionalizative perfluoroalkyloximation of alkenes has been developed for the first *** photochemical method allows for the synthesis of various perfluoroalkyl ethanone oximes with excellent regioselectivity and good functional group *** method employs the most common perfluoroalkyl source,perfluoroalkyl iodides,as Rf *** long-chain perfluoroalkyl groups,this approach could be extended to incorporating additional groups,including trifluoromethyl,difluoromethyl,sulfonyl,and malonate,selectively into olefins,resulting in a range ofβ-substituted ethanone ***,the potential of this method in the Fukuyama indole synthesis,generating novel 2-perfluoroalkylated 3-(α-oximidobenzyl)indoles via a radical cascade mechanism with 2-vinylphenylacryloyl isocyanate as the radical acceptor,presents a compelling avenue for drug *** protocol is efficient,scalable,and useful for late-stage modification of bioactive molecules.

关键词： Perfluoroalkyloximation Radical Fukuyama indole synthesis Difunctionalization EDA complex Regioselectivity Photochemistry Alkenes

Self-assembly of perovskite nanocrystals:From driving forces to applications

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Journal of Energy Chemistry 2024年第1期88卷 561-578,I0013页

作者： Yi li Fei Zhang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell *** review discusses the driving forces behind the self-assembly process of perovskite NCs,and the commonly used self-assembly methods and different self-assembly structures are ***,we summarize the collective optoelectronic properties and application areas of perovskite superlattice ***,we conclude with an outlook on the potential issues and future challenges in developing perovskite NCs.

关键词： Self-assembly Metal halide perovskite Nanocrystals Driving forces

Completeness of Induced Cotorsion Pairs in Representation Categories of Rooted Quivers

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2436-2452页

作者： Zhen Xing DI li Ping li li liANG Fei XU School of Mathematical Sciences Huaqiao University LCSM (Ministry of Education) School of Mathematics and Statistics Hunan Normal University Department of Mathematics Lanzhou Jiaotong University Gansu Provincial Research Center for Basic Disciplines of Mathematics and Statistics Department of Mathematics Shantou University

This paper focuses on a question raised by Holm and J?rgensen, who asked if the induced cotorsion pairs(Φ（X）, Φ（X）⊥) and(⊥Ψ（Y）, Ψ（Y）) in Rep（Q, A）—the category of all A-valued representations of a quiver Q—are complete whenever（X, Y） is a complete cotorsion pair in an abelian category A satisfying some mild conditions. We give an affirmative answer if the quiver Q is rooted. As an application, we show under certain mild conditions that if a subcategory L, which is not necessarily closed under direct summands, of A is special precovering（resp., preenveloping）, then Φ（L）(resp.,Ψ（L）) is special precovering（resp., preenveloping） in Rep（Q, A）.

关键词： 16G20 18G25 complete cotorsion pair Rooted quiver special precovering (preenveloping) subcategory

Erosion-induced recovery CO_(2) sink offset the horizontal soil organic carbon removal at the basin scale

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Science China Earth Sciences 2024年第6期67卷 2019-2033页

作者： lingxia WANG Xiaodong NIE Jiaqi li Yaojun liU Hui WANG Yazhe li Zhongwu li School of Geographic Science Hunan Normal UniversityChangsha 410081China Institute of Interdisciplinary Studies Hunan Normal University and Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake BasinChangsha 410081China College of Environmental Science and Engineering Hunan University and Key Laboratory of Environmental Biology and Pollution Control(Hunan University)Ministry of EducationChangsha 410082China

To improve soil carbon sequestration capacity,the full soil carbon cycle process needs to be understood and *** is essential to evaluate whether water erosion acts as a net source or sink of atmospheric CO_(2)at the basin scale,which encompasses the entire hydrological *** study introduced an approach that combined a spatially distributed sediment delivery model and biogeochemical model to estimate the lateral and vertical carbon fluxes by water erosion at the basin *** this coupling model to the Dongting Lake Basin,the results showed that the annual average amount of soil erosion during 1980-2020 was 1.33×10^(8)t,displaying a decreasing trend followed by a slight *** 12% of the soil organic carbon displacement was ultimately lost in the riverine systems,and the rest was deposited downhill within the *** average lateral soil organic carbon loss induced by erosion was 8.86×10^(11)g C in 1980 and 1.50×10^(11)g C in 2020,with a decline rate of 83%.A net land sink for atmospheric CO_(2)of 5.54×1011g C a^(-1)occurred during erosion,primarily through sediment burial and dynamic ***,ecological restoration projects and tillage practice policies are still significant in reducing erosion,which could improve the capacity of the carbon sink for recovery beyond the rate of horizontal carbon ***,our model enables the spatial explicit simulation of erosion-induced carbon fluxes using costeffective and easily accessible input data across large spatial scales and long ***,it offers a valuable tool for predicting the interactions between carbon dynamics,land use changes,and future climate.

关键词： Water erosion Sediment transfer Lateral soil carbon loss Land-atmosphere CO_(2) flux Dongting Lake Basin

Genetic association analysis-based networks and classification of human UCP1 polymorphisms

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Genes & Diseases 2024年第3期11卷 63-65页

作者： Donghai li State Key Laboratory of Pharmaceutical Biotechnology School of Life SciencesNanjing UniversityJiangsu 210023China

Uncoupling protein 1(UCP1,also known as thermogenin or SLC25A7)plays an important role in the uncoupling of oxidative phosphorylation and adaptive non-shivering thermogenesis(NST).The genomic location for UCP1 is chromosome 4 q31.1:140,555,770--140,568,961(GRCh38/hg38)and its size is 13,192 bases split into 6 *** dbSNP,3650 short genetic variations of human UCP1 are *** this study,UCP1 serves as an example to construct polymorphism-trait networks and enable a func-tional classification.

关键词： classification. UCP1 networks

Observation and verification of surface electrical explosion driven by radial-distributed pulsed current in laboratory lightning strike test

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High Voltage 2024年第1期9卷 137-149页

作者： Ruoyu Han Yuchen Cao Yakun liu Xi Chen Ting li Chen li Pengfei li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijingChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijingChina Department of Electrical Engineering Shanghai Jiaotong UniversityShanghaiChina Beijing Institute of Astronautical System Engineering BeijingChina Aerospace Research Institute of Materials and Processing Technology BeijingChina

The laboratory lightning test is essential for assessing the effectiveness of lightning strike protection(LSP).Particularly,direct lightning strike damage can be performed with pulsed current injection into the *** paper focuses on the dynamic process of arc plasma and shock wave behaviour in the vicinity of the‘strike’point.A rod-plate discharge load is built for testing aluminium and coated plate under 40-kA-level pulsed *** visualisation of the luminous discharge plasma and its flow field via high-speed photography(from different angles)is meticulously designed and implemented,synchronised with electro-physical *** results indicate some new mechanisms for lightning strike damage,apart from the impulse heat loading from the thermal *** transient current injection through the arc root concentrates on a thin skin layer(skin-depth effect),with the radial-attenuated current density,driving asynchronously electrical explosions on the plate *** inhomogeneous Joule heating of the plate leads to outwardly propagating phase transition and shock wave along the conductive *** addition,the electro-thermal instability is observed and regarded as the seed of irregular erosion *** information reveals two different plasma states of main discharge arc channel and adjacent surface electrical *** correspondence of the physical mechanism of electrical explosion and optical radiation is *** images for different regions depict erosion characteristics and summarise influencing factors,further confirming the mechanism *** research clarifies the role of skin-depth effect in transaction arc erosion for electrode,complements the electrical explosion theory with unevenly distributed current and helps optimise strategies of LSP.

关键词： electrical lightning radial

lightweight Malicious Code Classification Method Based on Improved Squeeze Net

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Computers, Materials & Continua 2024年第1期78卷 551-567页

作者： li li Youran Kong Qing Zhang School of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the growth of the Internet,more and more business is being done online,for example,online offices,online education and so *** this makes people’s lives more convenient,it also increases the risk of the network being attacked by malicious ***,it is important to identify malicious codes on computer systems ***,most of the existing malicious code detection methods have two problems:(1)The ability of the model to extract features is weak,resulting in poor model performance.(2)The large scale of model data leads to difficulties deploying on devices with limited ***,this paper proposes a lightweight malicious code identification model lightweight Malicious Code Classification Method Based on Improved SqueezeNet(LCMISNet).In this paper,the MFire lightweight feature extraction module is constructed by proposing a feature slicing module and a multi-size depthwise separable convolution *** feature slicing module reduces the number of parameters by grouping *** multi-size depthwise separable convolution module reduces the number of parameters and enhances the feature extraction capability by replacing the standard convolution with depthwise separable convolution with different convolution kernel *** addition,this paper also proposes a feature splicing module to connect the MFire lightweight feature extraction module based on the feature reuse and constructs the lightweight model *** malicious code recognition accuracy of LCMISNet on the BIG 2015 dataset and the Malimg dataset reaches 98.90% and 99.58%,*** proves that LCMISNet has a powerful malicious code recognition *** addition,compared with other network models,LCMISNet has better performance,and a lower number of parameters and computations.

关键词： lightweight neural network malicious code classification feature slicing feature splicing multi-size depthwise separable convolution

Concentration breaking on two optimization problems

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Science China Mathematics 2024年第7期67卷 1555-1570页

作者： Yong Huang Qinfeng li Qiuqi li School of Mathematics Hunan UniversityChangsha410082China

In the present paper, we study the boundary concentration-breaking phenomena on two thermal insulation problems considered on lipschitz domains, based on Serrin's overdetermined result, the perturbation argument, and a comparison of Laplacian eigenvalues with different boundary conditions. Since neither of the functionals in the two problems is C^(1), another key ingredient is to obtain the global H?lder regularity of minimizers of both problems on lipschitz domains. Also, the exact dependence on the domain of breaking thresholds is given in the first problem, and the breaking values are obtained in the second problem on ball domains, which are related to 2π in dimension 2.

关键词： spectral inequalities symmetry breaking Laplacian eigenvalue