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List Injective Coloring of Planar Graphs

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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 614-626页

作者： yin-dong jin Lian-ying MIAO School of Mathematics China University of Mining and TechnologyXuzhou 221116China

A k-coloring of a graph G is a mapping c:V(G)→{1,2,···,k}.The coloring c is called injective if any two vertices have a common neighbor get distinct colors.A graph G is injectively k-choosable if for any color list L of admissible colors on V(G)of size k allows an injective coloringφsuch thatφ(v)∈L(v)for each v∈V(G).Letχ;(G),χ;(G)denote the injective chromatic number and injective choosability number of G,*** this paper,we show thatχ;(G)≤△+4 if△≥22 andχ;(G)≤△+5 if△≥15,where G is a triangle-free planar graph and without intersecting 4-cycles.

关键词： planar graph injective coloring list coloring

Optimization of territorial space layout in China

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Journal of Geographical Sciences 2024年第9期34卷 1719-1738页

作者： dong yin jin Gui DENG Xiangzheng Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education Fujian Normal UniversityFuzhou 350007China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China School of Economics and Management China University of GeosciencesWuhan 430079China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China

The evolution of territorial space is intrinsically linked to economic growth, societal welfare, and ecological preservation. In the context of escalating spatial conflicts and stringent resource limitations, resource efficiency has emerged as a fundamental pillar for the scientific optimization of territorial space layout. Drawing upon resource efficiency metrics from cities nationwide, this study constructs scenarios for territorial space development and conservation, assesses developmental capacity under varying preferences, and subsequently delineates strategic blueprints using an integrated “point-axis-area” approach. The findings reveal the following:(1) Resource efficiency in China has witnessed a consistent uptick, yet remains modest overall, with marked regional disparities.(2) Throughout the investigation period, developmental capacity has seen progressive enhancement, with a pronounced capacity in scenarios favoring development, radiating axially from urban conglomerates.(3) The layout of pivotal points and developmental axes has transitioned from a “tri-pillar” to a diamond configuration, with the coastal corridor, Harbin-Beijing-Guangzhou corridor, and the corridor along the Yangtze River standing out.(4) Strategic points progressively converge along key axes, whereas dominant regions exhibit clear differentiation on either side of the Hu Huanyong Line. By integrating elements of the territorial spatial structure,this paper proposes blueprints for “five horizontal and three vertical zones with eight cores and three areas,” “four horizontal and three vertical zones with six cores and three areas,”and “three horizontal and four vertical zones with five cores and three areas,” corresponding to scenarios of prioritizing development, status quo maintenance, and prioritizing conservation, respectively. The outcomes of this research offer a technical foundation and theoretical guidance for the pursuit of high-quality territorial space development and a vision

关键词： territorial space resource efficiency development and conservation developmental capacity territorial space blueprints China

Flocking of a Cucker–Smale Type Model with Compactly Supported Interaction Functions

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2285-2296页

作者： Chun yin jin Shuang Zhi LI College of Science China Agricultural UniversityBeijing 100083P.R.China

How to analyze flocking behaviors of a multi-agent system with local interaction functions is a challenging problem in *** and Tadmor in 2011 also stressed the significance to assume that the interaction function is rapidly decaying or cut-off at a finite distance(*** and Tadmor in ***.2011).In this paper,we study the flocking behavior of a Cucker–Smale type model with compactly supported interaction *** properties of a connected stochastic matrix,together with an elaborate analysis on perturbations of a linearized system,we obtain a sufficient condition imposed only on model parameters and initial data to guarantee ***,it is shown that the system achieves flocking at an exponential rate.

关键词： Cucker-Smale model local interaction flocking stochastic matrix neighbor graph

Dynamic Scene Graph Generation of Point Clouds with Structural Representation Learning

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Tsinghua Science and Technology 2024年第1期29卷 232-243页

作者： Chao Qi Jianqin yin Zhicheng Zhang jin Tang School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China Standard and Metrology Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

Scene graphs of point clouds help to understand object-level relationships in the 3D *** graph generation methods work on 2D structured data,which cannot be used for the 3D unstructured point cloud *** point-cloud-based methods generate the scene graph with an additional graph structure that needs labor-intensive manual *** address these problems,we explore a method to convert the point clouds into structured data and generate graphs without given ***,we cluster points with similar augmented features into groups and establish their relationships,resulting in an initial structural representation of the point ***,we propose a Dynamic Graph Generation Network(DGGN)to judge the semantic labels of targets of different *** dynamically splits and merges point groups,resulting in a scene graph with high *** show that our methods outperform other baseline *** output reliable graphs describing the object-level relationships without additional manual labeled data.

关键词： scene graph generation structural representation point cloud

A Review on Particle Reinforced Mg Matrix Composites Fabricated by Powder Metallurgy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 391-400页

作者： Zhiyuan Liu Li jin Jian Zeng Fulin Wang Fenghua Wang Shuai dong Jie dong National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This paper provides a comprehensive review of research progress in particle-reinforced Mg matrix composites prepared via powder *** article discusses different strategies,such as micro-sized,nano-sized particles,and multi-particle hybridization,which has been employed to enhance the performance of the *** addition,a range of preparation techniques that optimize the dispersion of the reinforcing particles are *** paper also highlights how the different configurations between the reinforcements and matrix alloy impact the composites’***,the article outlines the prospects of particles reinforced Mg matrix composites fabricated via powder metallurgy and recommends modification methods that could be explored to further develop these materials for various applications.

关键词： Magnesium matrix composites Reinforcing particle Powder metallurgy Mechanical properties Configuration

Time-domain dynamic constitutive model suitable for mucky soil site seismic response

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 1-13页

作者： dong Qing Chen Su jin Liguo Zhou Zhenghua Li Xiaojun Architectural Engineering Institute Huaiyin Institute of TechnologyHuai’an 223600China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100020China Institute of Geophysics China Earthquake AdministrationBeijing 100089China College of Transportation Science and Engineering Nanjing Tech UniversityNanjing 211816China

Soil nonlinear behavior displays noticeable effects on the site seismic *** study proposes a new functional expression of the skeleton curve to replace the hyperbolic skeleton *** integrating shear modulus and combining the dynamic skeleton curve and the damping degradation coefficient,the constitutive equation of the logarithmic dynamic skeleton can be obtained,which considers the damping effect in a soil dynamics *** on the finite difference method and the multi-transmitting boundary condition,a 1D site seismic response analysis program called Soilresp1D has been developed herein and used to analyze the time-domain seismic response in three types of *** the same time,this study also provides numerical simulation results based on the hyperbolic constitutive model and the equivalent linear *** results verify the rationality of the new soil dynamic constitutive *** can analyze the mucky soil site nonlinear seismic response,reflecting the deformation characteristics and damping effect of the silty *** hysteresis loop area is more extensive,and the residual strain is evident.

关键词： seismic response time-domain dynamic constitutive model logarithmic dynamic skeleton dampening effect mucky soil

Coexistence of adeno-associated virus 2 with adenovirus 18 or herpesvirus may be associated with severe lingual papillomatosis in an immunocompromised individual

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Virologica Sinica 2024年第4期39卷 705-707页

作者： Jie-Mei Yu Ze-yin Liang Yuan-Hui Fu Xiang-Lei Peng Yan-Peng Zheng Yu-Jun dong jin-Sheng He College of Life Sciences and Bioengineering Beijing Jiaotong UniversityBeijing100044China Department of Hematology Peking University First HospitalBeijing100034China

Dear Editor,Patients undergoing allogeneic hematopoietic stem cell transplantation(HSCT)often experience a significant reduction in immune function due to factors such as severe lymphopenia,immunosuppressive treatment,and the development of graft-versus-host disease,rendering them more susceptible to severe infections(Sahin et al.,2016).Traditional diagnostic approaches are limited in sensitivity,speed,and assay targets,thus failing short of meeting the diagnostic demands(Qu et al.,2022).However,next-generation sequencing(NGS)has greatly improved the accuracy and efficiency of diagnosing various diseases(Schuler et al.,2022),and has been widely utilized for pathogen detection in samples from HSCT patients(Armstrong et al.,2019;Peng et al.,2021).In this study,we employed viral metagenomics analysis using high-throughput sequencing on fecal and tissue samples from a patient with HSCT experiencing severe lingual papillomatosis.

关键词： al. papilloma rendering

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

Superior Anodic Lithium Storage in Core-Shell Heterostructures Composed of Carbon Nanotubes and Schiff-Base Covalent Organic Frameworks

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 150-157页

作者： Jiang, Nan Qi, Mengpei Jiang, Yalong Fan, yin jin, Shiwei Yang, yingkui South Cent Minzu Univ Sch Chem & Mat Sci Wuhan 430074 Peoples R China Wuhan Text Univ State Key Lab New Text Mat & Adv Proc Technol Wuhan 430200 Peoples R China

Covalent organic frameworks (COFs) after undergoing the superlithiation process promise high-capacity anodes while suffering from sluggish reaction kinetics and low electrochemical utilization of redox-active sites. Herein, integrating carbon nanotubes (CNTs) with imine-linked covalent organic frameworks (COFs) was rationally executed by in-situ Schiff-base condensation between 1,1 '-biphenyl]-3,3 ',5,5 '-tetracarbaldehyde and 1,4-diaminobenzene in the presence of CNTs to produce core-shell heterostructured composites (CNT@COF). Accordingly, the redox-active shell of COF nanoparticles around one-dimensional conductive CNTs synergistically creates robust three-dimensional hybrid architectures with high specific surface area, thus promoting electron transport and affording abundant active functional groups accessible for electrochemical utilization throughout the whole electrode. Remarkably, upon the full activation with a superlithiation process, the as-fabricated CNT@COF anode achieves a specific capacity of 2324 mAh g-1, which is the highest specific capacity among organic electrode materials reported so far. Meanwhile, the superior rate capability and excellent cycling stability are also obtained. The redox reaction mechanisms for the COF moiety were further revealed by Fourier-transform infrared spectroscopy in conjunction with X-ray photoelectron spectroscopy, involving the reversible redox reactions between lithium ions and C=N groups and gradual electrochemical activation of the unsaturated C=C bonds within COFs. Coupling conductive carbon nanotubes with redox-active imine-linked covalent organic frameworks generates core-shell heterostructures capable of building 3D hierarchical architectures with fully exposed active sites for boosting anodic lithium storage. image

关键词： heterostructured anode core-shell nanostructures carbon nanotubes polymeric Schiff-bases covalent organic frameworks BATTERIES