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Evolution and Governance of the Structure of Marine Economic Networks in China’s Coastal Areas: Based on Sea-related A-share listed Companies

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Chinese Geographical Science 2024年第5期34卷 899-916页

作者： li bo CAO Gai Key Research Base of Humanities and Social Sciences of Ministry of Education Institute of Marine Sustainable DevelopmentLiaoning Normal UniversityDalian 116029China School of Maritime Economics and Management Dalian Maritime UniversityDalian 116026China

Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic ***,as the focus of urban research shifts from internal static attributes to external dynamic linkages,the importance of marine economic net-work research is beginning to *** construction of the marine economic network in China’s coastal areas is necessary to change the flow of land and sea resources and optimize regional marine economic *** data from headquarters and branches of sea-related A-share listed enterprises to construct the marine economic network in China,we use social network analysis(SNA)to discuss the characteristics of its evolution as of 2010,2015,and 2020 and its *** following results were obtained.1)In terms of topological characteristics,the scale of the marine economic network in China’s coastal areas has accelerated and expan-ded,and the connections have become increasingly close;thus,this development has complex network characteristics.2)In terms of spatial structure,the intensity of the connection fluctuates and does not form stable development support;the group structure gradually becomes clear,but the overall pattern is fragmented;there are spatial differences in marine economic agglomeration radiation;the radi-ation effect of the eastern marine economic circle is obvious;and the polarization effect of northern and southern marine economic circles is *** this basis,we construct a framework for the governance of a marine economic network with the market,the government,and industry as the three governing *** clarifying the driving factors and building objectives of marine economic network construction,this study aims to foster the high-quality development of China’s marine economy.

关键词： marine economic network sea-related A-share listed companies social network analysis(SNA) network governance China’s coastal areas

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Processing,microstructure,and properties of porous ceramic composites with directional channels

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Journal of Materials Science & Technology 2024年第1期168卷 1-15页

作者： bo zhang Yang Yang Xueling Fan Key Laboratory of Service Performance and Protection Technology in Extreme Environments Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China

Porous ceramic composites with directional microchannels from micrometer to dozens of micrometer levels have attracted more and more attention in various fields including aerospace,biomedicines,and thermal insulation due to their excellent fluid permeability,mechanical properties,*** this article,we summarize the recent directional porous ceramics developments including their main processing routes and respective ***,the properties get from different processing routes have been com-pared and analyzed in terms of microstructures,mechanical properties,and *** has been given to the deeper understanding which can allow one to control the microstructural features of these porous ceramic composites to obtain the desired *** work can provide a useful reference for the development and application of porous ceramic composites with directional microchan-nels.

关键词： Porous ceramic composites Directional microchannels Processing routes Permeability

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Deflagration and detonation induced by shock wave focusing at different Mach numbers

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Chinese Journal of Aeronautics 2024年第2期37卷 249-258页

作者： Zezhong YANG Jun CHENG bo zhang School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

Shock wave focusing is an effective way to create a hot spot or a high-pressure and hightemperature region at a certain place,showing its unique usage in detonation initiation,which is beneficial for the development of detonation-based *** flame propagation behavior after the autoignition induced by shock wave focusing is crucial to the formation and self-sustaining of the detonation *** this study,wedge reflectors with two different angles(60°and 90°)and a planar reflector are employed,and the Mach number of incident shock waves ranging from 2.0 to 2.8 is utilized to trigger different flame propagation *** pressure transducers and the high-speed schlieren imaging system are both employed to investigate the shock-shock collision and ignition *** results reveal a total of four flame propagation modes:deflagration,DDT(Deflagration-to-Detonation Transition),unsteady detonation,and direct *** detonation wave formed in the DDT and unsteady detonation mode is only approximately 75%-85%of the Chapman-Jouguet(C-J)speed;meanwhile,the directly induced detonation wave speed is close to the C-J *** waves,which are strong evidence for the existence of detonation waves,are discovered in *** usage of wedge reflectors significantly reduces the initial pressure difference ratio needed for direct detonation *** also provide a practical method for differentiating between detonation and deflagration modes,which involves contrasting the speed of the reflected shock wave with the speed of the theoretically nonreactive reflected shock *** findings should serve as a reference for the detonation initiation technique in advanced detonation propulsion engines.

关键词： Deflagration Detonation Hydrogen Ignition Shock wave focusing

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Characteristics of microscopic pore heterogeneity and development model of Wufeng‒Longmaxi Shales in the Pengshui area of south-east Chongqing

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Frontiers of Earth Science 2024年第1期18卷 188-203页

作者： Lu SUN Zhigang WEN Guisong HE Peixian zhang Chenjun WU liwen zhang Yingyang XI bo li College of Resources and Environment Yangtze UniversityWuhan 430100China Research Institute of Exploration and Development Sinopec East China CompanyNanjing 210011China

Normal-pressure shale gas reservoirs are widely distributed in south-eastern Chongqing and show good potential for resource *** paper reports the organic matter(OM),physical,and pore characteristics,mineral composition,and gas content of representative shale samples from the Upper Ordovician Wufeng Formation and Member 1 of the Lower Silurian Longmaxi Formation(Long 1 Member).Microscopic pores within different shale layers of the Long 1 Member were classified,quantitatively evaluated,and their development mechanisms were systematically *** found that OM characteristics,mineral composition,and pore type were the main factors affecting the enrichment and preservation of shale *** characteristics of the Long 1 Member are mainly controlled by changes in the sedimentary *** are evident differences in total organic carbon content and mineral composition vertically,leading to a variable distribution of pores across different *** matter abundance controls the degree of OM pore development,while clay minerals abundance control the development of clay mineral-related *** organic carbon content generally controls the porosity of the Long 1 Member,but clay minerals also play a role in OM-poor *** connectivity and permeability are influenced by the development of pores associated with brittle *** propose a microscopic pore development model for the different *** geochemical data and this pore development model,layers 1‒4 are considered to be excellent shale gas preservation and enrichment *** preservation conditions in layers 5‒7 result in high levels of shale gas *** 8‒9 possess a better sealing condition compared with layers 5‒7 and are conducive to the enrichment and preservation of shale gas,and can thus be used as future potential target *** research provides a theoretical basis for exploring and evaluating shale gas potential in the studied region or other co

关键词： shale gas pore characteristics Longmaxi Formation reservoir model

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Efficient second and third harmonic generation in dual-layer lithium niobate microdisk resonator

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 33-38页

作者： Zhenzhong Hao Xiao Wu Qiang Luo zhang li Rui Ma Fang bo Feng Gao Guoquan zhang Jingjun Xu MOE Key Laboratory of Weak-light Nonlinear Photonics TEDA Institute of Applied Physics and School of PhysicsNankai UniversityTianjin 300457China

lithium niobate thin film frequency doubler has extensive applications in the preparation of classical and quantum *** this study,we successfully fabricated microdisk resonators with a quality factor of 2.2×10^(5) in reverse-polarization dual-layer x-cut lithium niobate for the first *** on the modal phase matching condition,efficient second harmonic generation with a record normalized conversion efficiency of~56000%W-1 and cascaded third harmonic generation with an efficiency of~6500%W-2 were obtained in the microdisk *** with the periodically poled lithium niobate microcavity,the complex domain structure preparation processes are *** work provides a scheme for achieving highly efficient second-order nonlinear effects in non-periodically poled microcavities.

关键词： harmonic lithium niobate

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Enhancing thermoelectric performance in P-type Mg_(3)Sb_(2)-based Zintls through optimization of band gap structure and nanostructuring

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Journal of Materials Science & Technology 2024年第3期170卷 25-32页

作者： Yi-bo zhang Ji-Sheng liang Chengyan liu Qi Zhou Zhe Xu Hong-bo Chen Fu-cong li Ying Peng Lei Miao Guangxi Key Laboratory of Information Material Engineering Research Center of Electronic Information Materials and DevicesMinistry of EducationSchool of Material Science and EngineeringGuilin University of Electronic TechnologyGuilin 541004China Guangxi Key Laboratory for Relativity Astrophysics Center on Nanoenergy ResearchGuangxi Key Laboratory of Processing for Nonferrous Metal and Featured MaterialsSchool of Physical Science&TechnologyGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Precision Navigation Technology and Application Guilin University of Electronic TechnologySchool of Information and CommunicationGuilin 541004China

P-type Mg_(3)Sb_(2)-based Zintls have attracted considerable interest in the thermoelectric(TE)field due to their environmental friendliness and low ***,compared to their n-type counterparts,they show relatively low TE performance,limiting their application in TE *** this work,we simultaneously introduce Bi alloying at Sb sites and Ag doping at Mg sites into the Mg_(3)Sb_(2)to coopera-tively optimize the electrical and thermal properties for the first time,acquiring the highest ZT value of∼0.85 at 723 K and a high average ZT of 0.39 in the temperature range of 323-723 K in sample Mg_(2.94)Ag_(0.06)Sb_(1.9)Bi_(0.1).The first-principle calculations show that the codoping of Ag and Bi can shift the Fermi level into the valence band and narrow the band gap,resulting in the increased carrier concentration from 3.50×10^(17)cm^(-3)in the reference Mg 3 Sb 0.9 Bi 0.1 to∼7.88×10^(19)cm^(-3)in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi *** a result,a remarkable power factor of∼778.9μW m^(-1)K^(-2)at 723 K is achieved in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi ***,a low lattice thermal conductivity of∼0.48 W m^(-1)K^(-1)at 723 K is also obtained with the help of phonon scattering at the distorted lattice,point defects,and nano-precipitates in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi *** synergistic effect of using the multi-element co-doping/-alloying to optimize electrical properties in Mg_(3)Sb_(2)holds promise for further improving the TE performance of Zintl phase materials or even others.

关键词： Thermoelectric materials Band engineering Nanostructuring P-type Mg_(3)Sb_(2) Ag and Bi Co-doping

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TEPG:a traffic engineering based power-aware greedy routing algorithm in backbone networks with bundled links

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Frontiers of Computer Science 2024年第1期18卷 243-245页

作者： Jinhong zhang Xingwei WANG Ruixia li bo YI Min HUANG Dongxing SHUI School of Electronic and Information Engineering West Anhui UniversityLu’an 237012China State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China School of Computer Science and Engineering Northeastern UniversityShenyang 110169China School of Information Science and Engineering Northeastern UniversityShenyang 110819China

1 Introduction and main contributions Various power-aware solutions have been proposed to address the alarming energy waste and consequent serious environmental issues since Gupta and Singh initiated the seminal study on green networking problem in *** of the researches concentrated their efforts on power-aware networking under the non-bundled link scenarios by leveraging the dynamic power management based Low Power Idle(LPI)policy which was defined and standardized in the IEEE 802.3az ***,in modern backbone networks,pairs of routers are typically connected,for each traffic direction,by multiple physical links that form one logical bundled link,which is the link aggregation technique defined and standardized in IEEE 802.1AX.

关键词： power bundle backbone

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Differences in leaf cuticular wax induced by whole-genome duplication in autotetraploid sour jujube

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Horticultural Plant Journal 2024年第1期10卷 66-76页

作者： Meng li Chenxing zhang Lu Hou Xinru liu Hanqing Zhao Xiaoming Pang Wenhao bo Yingyue li National Engineering Research Center of Tree Breeding and Ecological Restoration College of Biological Sciences and TechnologyBeijing Forestry UniversityBeijing 100083China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants Ministry of EducationCollege of Biological Sciences and TechnologyBeijing Forestry UniversityBeijing 100083China The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration Beijing Forestry UniversityBeijing 100083China

Drought-resistant plants exhibit strong water retention *** this regard,the autotetraploid sour jujube leaves exhibit better water retention than diploid *** comparisons and physiological comparisons of diploid and autotetraploid leaves showed that the autotetraploid leaves had thicker leaf cuticles and more leaf wax accumulation than the diploid leaves,which could reduce cuticle permeability and improve the drought tolerance of *** this study,the cuticular wax crystalloids on the adaxial and abaxial sides of young and mature jujube leaves were observed in the two ploidy types,and unique cuticular wax crystalloids covering a large area of the cuticle on autotetraploid sour jujube leaves may provide an advantage in reducing leaf non-stomata transpiration and improving plant drought *** on the transcriptome,115 differentially expressed genes between diploids and autotetraploids were further analyzed and found to be involved in the accumulation of cuticular wax components,including terpenoids,fatty acids,and lipids,as well as ABC transporter and wax biosynthetic ***,14 genes differentially expressed between glossy autotetraploid leaves and nonglossy diploid leaves,such as LOC107414787,LOC107411574 and LOC107413721,were screened as candidate genes by qRT-PCR *** findings provided insights into how polyploidization improved drought tolerance.

关键词： Autotetraploid Jujube Drought tolerance Cuticular wax RNA-seq

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Optical and electrical anisotropy regulation engineering of low-dimensional materials toward polarized detection and imaging applications

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Rare Metals 2024年第7期43卷 2968-2993页

作者： Jian-Bin zhang Nan Zhou li-Hui zhang Cong-Hui Shang Jia-Xuan li Yi Zhao Guo-Hui Jia Ru-Sen Yang Hua Xu Xiao-bo li Shaanxi Joint Key Laboratory of Graphene Shaanxi Key Laboratory of High-Orbits-Electron Materials and Protection Technology for AerospaceShaanxi Joint Key Laboratory of GrapheneSchool of Advanced Materials and NanotechnologyXidian UniversityXi'an710126China Guangzhou Institute of Technology Xidian UniversityGuangzhou 710068China Xi'an Thermal Power Research Institute Co. LtdXi'an 710054China Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an Xi'an 710119China

Polarized-sensitive image sensors are a kind of photodetector with great development potential due to their enhanced ability to detect and identify the target objects from the aspect of spatial,spectral and polarized ***,low-dimensional anisotropic materials with inherent anisotropic properties,ultrathin thickness,tunable bandgap and feasible integration with complementary metal oxide semiconductor(CMOS)fabrication processes have attracted great interest for their facilitation of polarized photodetector devices *** the polarized detection performance of low-dimensional materials to satisfy realistic needs stimulates the exploration of modulation of anisotropic *** this review,we comprehensively introduce the latest research progress in modulating the optical and optoelectronic anisotropy characteristics of low-dimensional *** strategy of anisotropy regulation through crystal structure engineering and coupling system is discussed ***,the latest progress in image recognition applications using anisotropic low-dimensional materials is reviewed in ***,we summarize the challenge and propose future opportunities in the practical application of polarized-sensitive imaging photodetectors based on low-dimensional anisotropic materials.

关键词： Anisotropy Polarized detection Image recognition Low-dimensional materials

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Access to High-Molecular-Weight Polyethylenes through High Temperature Ethylene Polymerization Catalysed by Ethylene-Bridged ansa-(3-R-Cyclopentadienyl)(Fluorenyl) Zirconocene Complexes

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Chinese Journal of Polymer Science 2024年第1期42卷 42-51,I0007页

作者： bo li Haiyan Ma Jiling Huang Shanghai Key Laboratory of Functional Materials Chemistry and Laboratory of Organometallic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of C1-symmetric ethylene-bridged ansa-(3-R-cyclopentadienyl)(fluorenyl) metallocene complexes(Zr: 1-5;Hf: 6) have been synthesized, characterized and investigated as catalyst precursors for the high temperature ethylene polymerization. Using methylaluminoxane(MAO) as the cocatalyst, zirconium complexes 1-5 bearing a bulky substituent on the 3-position of the cyclopendienyl ring showed high catalytic activities up to 1.48×10^(7) g PE·mol_(Zr)^(-1)·h^(-1) toward the polymerization of ethylene and afforded polyethylenes with high molecular weights(1.49×10^(5)-6.31×10^(5) g/mol), meanwhile exhibting great thermal stability at high temperatures up to 120 ℃ together with a long catalytic life time up to 2 h. By adopting low Al/Zr ratios, such as 125, polyethylenes with ultra high molecular weights up to 2.86×106 g/mol were obtained. It is worthy of noting that zirconium complexes 1-4 bearing a substituent with an aryl pendant showed temperature-dependent activities, which increased rapidly with the increase of polymerization temperature, thus weak interaction of the pendent aryl group with the cationic active center is proposed to account for the very low activities displayed at low temperatures. In contrast to zirconocene complexes 1-5, hafnocene complex 6 only displayed very low catalytic activities toward the polymerization of ethylene and afforded polyethylenes with molecular weights ten times smaller than those obtained by zirconocene complexes 1-5. Zirconocene complexes 1-5 were also able to catalyse the polymerization of propylene at high temperatures, but only afforded waxes with low molecular weights.

关键词： ansa-Metallocene Ethylene Propylene Polymerization High temperature

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