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Frontiers of Architectural Research 2024年第2期13卷 305-318页

作者： bo wan Dongyang wan Qiang Sheng School of Architecture and Design Beijing Jiaotong UniversityBeijing 100044China

This paper,set against the backdrop of expanding urban rail networks and dynamic urban development,focuses on the distribution and evolution of commercial Points of Interests(POIs)within the central urban rail transit areas of Beijing.The study examines data from four different years-2008,2013,2017,and 2020-to observe the temporal evolution of commercial entities.It identifies stable explanatory variables affecting the distribution and evolution of commercial POIs,which include rail transit accessibility,characteristics of the working and residential population distribution around stations,and the construction intensity in the vicinity of station areas.Through statistical analysis and model building,relatively stable linear regression equations were established,with R2 values generally maintained above 0.5(except for 2017).The study advances our understanding of the influence of rail transit on urban commercial spaces and how this influence shifts with temporal and urban developmental changes.It elucidates the correlation between changes in the number of businesses and spatial configuration,offering insights and information for urban planners and policy makers.This research also serves as a model for exploring the interplay between urban rail transit and commercial spaces in other major cities.

关键词： Urbanrail transit areas Spatial configuration Distributionand evolution of commercial POls

Impact Analysis of Microscopic Defect Types on the Macroscopic Crack Propagation in Sintered Silver Nanoparticles

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 441-458页

作者： Zhongqing Zhang bo wan Guicui Fu Yutai Su Zhaoxi Wu Xiangfen wang Xu Long School of Reliability and Systems Engineering Beihang UniversityBeijing100191China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China China Aerospace Components Engineering Center Beijing100098China

Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs.

关键词： Sintered silver nanoparticles defect types microscopic defect evolution macroscopic crack propagation molecular dynamics simulation cohesive zone model

Multi-spherical interactions and mechanisms of hydrocarbon enrichment in the Southeast Asian archipelagic tectonic system

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Science China Earth Sciences 2024年第2期67卷 566-583页

作者： Rixiang ZHU Hongjun wanG Huajian wanG Xiaomei wanG bo wan wang ZHANG Houqin ZHU Yuke LIU Junlai LIU Qingren MENG Fang HAO Zhijun JIN State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China State Key Laboratory of Enhanced Oil and Gas Recovery PetroChina Research Institute of Petroleum Exploration and DevelopmentBeijing100083China School of Earth Sciences and Resources China University of GeosciencesBeijing100083China State Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China Institute of Energy Peking UniversityBeijing100871China

Global cooling began since 50 Ma,but a warm climate was maintained in the archipelagic tectonic system in Southeast Asia where a wealth of Cenozoic oil and gas resources was formed and preserved.From the perspective of Earth system,this study analyzes Cenozoic tectonic activities,climatic and environmental evolution,and petroleum enrichment in Southeast Asia,and provides the following insights:(1)Subduction of oceanic plates and the extension of overlying continental lithosphere resulted in widespread volcanic eruptions as well as the formation of rift basins and shallow marine shelves,leading to complex interactions between deep tectonic processes and Earth’s surface including mountains,basins,and seas.(2)Microcontinental accretion and prolonged stay in equatorial low-latitude regions have changed trade winds into monsoons,altered ocean current pathways and flow rates,and profoundly affected rainfall and climate.(3)The archipelagic tectonic system,coupled with a hot and rainy climate,fostered tropical rainforests,mangroves,and phytoplankton,providing abundant organic matter and promoting the development of petroleum resources.(4)Combinations of rift basin development and marine transgression and regression led to an effective superposition of source-reservoir-seal combinations from multiplepetroleum systems.Rapid deep burial of organic matter and high geothermal gradients facilitated the generation and large-scale accumulation of oil and gas.(5)Multi-spherical(such as atmosphere,biosphere,hydrosphere and lithosphere)interactions on the Earth,which resulted from the convergence of multiple tectonic plates,are believed as the primary driver for exceptional enrichments of Cenozoic oil and gas resources in Southeast Asia.These understandings are significant for developing theories of oil and gas enrichment under the guidance of Earth System Science.In order to continue making significant oil and gas exploration discoveries in the deep-layers,deep-waters,and unconventional oil and gas fields of Southeast Asia,attenti

关键词： Southeast Asia Archipelagic tectonic system Interactions of Earth’s spheres Oil and gas resources Cenozoic

Thiazoloisoindigo-based Polymer Semiconductors: Synthesis,Structure-Property Relationship, Charge Carrier Polarity, and Field-Effect Transistor Performance

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Chinese Journal of Polymer Science 2024年第1期42卷 24-31,I0006页

作者： bo-Wen Li Miao Xiong Mei-Hua Liu Zhi-Gao Li Long Sang Zi-Han Xiong Biao Xiao Jian Pei Xiao-bo wan Key Laboratory of Optoelectronic Chemical Materials and Devices Ministry of EducationSchoolofOptoelectronic Materials&TechnologyJianghan UniversityWuhan430056China Bejing National Laboratoryfor Molecular Sciences the Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Developing new polymeric semiconductors with excellent device performance is essential for organic electronics. Herein, we synthesized two new thiazoloisoindigo(Tz II)-based polymers, namely, P(Tz II-d Th-d Th) and P(Tz II-d Th-d Tz), by copolymerizing thiophene-flanked Tz II with bithiophene and bithiazole, respectively. Owing to the more electron-deficient nature of bithiazole than bithiophene, P(Tz II-d Th-d Tz)possesses deeper LUMO/HOMO levels of-3.45/-5.47 e V than P(Tz II-d Th-d Th)(-3.34/-5.32 e V). The organic field-effect transistor(OFET) devices based on P(Tz II-d Th-d Th) exhibited p-type behaviors with an average hole mobility value as high as 1.43 cm^(2)·V^(-1)·s^(-1), while P(Tz II-d Th-d Tz)showed typical ambipolar characteristics with average hole and electron mobilities of 0.38 and 0.56 cm^(2)·V^(-1)·s^(-1). In addition, we compared the performances of both polymers with other Tz II-based polymers reported in our previous work, and showed that the charge carrier polarity can be manipulated by adjusting the number of the thiophene units between the acceptor unit. As the increase of the number of thiophene rings,charge carrier polarity shifts from electron-dominated ambipolar transport to hole-dominated ambipolar transport and then to unipolar hole transport in OFETs, which provides an effective molecular design strategy for further optimization of polymer OFET performance.

关键词： Field-effect transistor Charge carrier polarity Thiazoloisoindigo

Erratum to:Geodynamic processes of the southeastern Neo-Tethys Ocean and the formation mechanism of the curved subduction system in Southeast Asia

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Science China Earth Sciences 2024年第3期67卷 894-894页

作者： Weiwei DING Rixiang ZHU bo wan Liang ZHAO Xiongwei NIU Pan ZHAO Baolu SUN Yanghui ZHAO Key Laboratory of Submarine Geoscience&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China State Key Laboratory of Lithosphere Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The research paper"Geodynamic processes of the southeastern Neo-Tethys Ocean and the formation mechanism of the curved subduction system in Southeast Asia"(Sci China Earth Sci,2023,66:703-717)contained errors.The corr... 详细信息

关键词： southeastern subduction Tethys

Variation in bombyx mori immune response against fungal pathogen Beauveria bassiana with variability in cell wallβ-1,3-glucan

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Insect Science 2024年第1期31卷 211-224页

作者： Yulong wang Zhen Liu Xuebing Yin Shihong Liu Kai wang Rongjie wan Haoran Chen Xinyang Li bo Huang Anhui Provincial Key Laboratory of Microbial Pest Control Anhui Agricultural UniversityHefeiChina

Entomopathogenic fungi are protected by a cell wall with dynamic structure for adapting to various environmental conditions.β-1,3-Glucan recognition proteins activate the innate immune system of insects by recognizing surface molecules of fungi.However,the associations between pathogenicity and the different components of entomopathogenic fungal cell walls remain unclear.Three Beauveria bassiana strains were selected that have significantly differing virulence against bombyx mori.The molecular mechanisms underlying the immune response in B.mori were investigated using RNA sequencing,which revealed differences in the immune response to different B.bassiana strains at 12 h post-infection.Immunofluorescence assays revealed thatβ-1,3-glucan content had an opposite trend to that of fungal virulence.β-1,3-Glucan injection upregulated BmβGRP4 expression and significantly reduced the virulence of the high-virulence strain but not that of the medium-virulence or low-virulence strains.BmβGRP4 silencing in B.mori with RNA interference resulted in the opposite virulence pattern,indicating that the virulence of B.bassiana was affected by the cell walls’content ofβ-1,3-glucan,which could be recognized by BmβGRP4.Furthermore,interference with the gene CnA(calcineurin catalytic A subunit)involved inβ-1,3-glucan synthesis eliminated differences in virulence between B.bassiana strains.These results indicate that strains of a single species of pathogenic fungi that have differing cell wall components are recognized differently by the innate immune system of B.mori.

关键词： ombyx mori BmβGRP4 innate immunity insect fungal pathogen virulence

Adverse effect of niobium and boron on hot deformation behavior of sulfur-containing steel

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Journal of Iron and Steel Research(International) 2024年第1期31卷 252-263页

作者： Guo-ning He Shi-qi wan bo Jiang Chao-lei Zhang Ya-zheng Liu Chun-jing Wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were investigated.Hot compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate observations.Hot compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was better.The tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,respectively.The addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the deformability.In addition,the interaction between inclusions and microalloyed elements was also significant.NbC particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.

关键词： Hot deformation Gear steel Processing map Dynamic recrystallization Microalloying

The influence of Tethyan evolution on changes of the Earth's past environment

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Science China Earth Sciences 2023年第12期66卷 2653-2665页

作者： bo wan Fuyuan WU Rixiang ZHU State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

Understanding changes in Earth's past can provide valuable insights into prediction of its future.An example is the interactions between the internal and external spheres of Earth.The cyclical northward breakup-drift of Gondwana,driven by the opening and closure of Proto-,Paleo-,and Neo-Tethyan oceans,facilitated the transfer of landmasses from the southern to the northern hemisphere,traversing the tropic region.We have observed a compelling correlation between episodic increases in landmass area within the tropic regions(those lying at less than 20°latitude)and a subsequent temperature decrease during the three major glacial periods in the last 500 million years.This phenomenon can be attributed to low latitude regions receiving more solar energy influx on Earth's surface than high latitude areas.In addition,an increase of landmass in tropic regions(low latitude)attenuates the net energy absorption by the Earth's surface,consequently impeding the conduction and convection of absorbed energy toward the poles.The result is a decrease in global surface temperature.The tropic regions,benefiting from abundant sunlight,create an ideal environment for the proliferation of marine plankton species.These species are important in the generation of organic-rich sediment.Massive biological debris is therefore deposited on continental margins when a continent drifts across the tropic region.This creates favorable conditions for future hydrocarbon and reservoir formation.Northward subduction of organic-rich sediments during the closure of the Tethyan oceans results in the generation of mafic arc magmas with low oxygen fugacity.This chemical environment helps the mineralization of reduced-type ore deposits such as tungsten,tin,and lithium.Subducted-driven plate tectonics in the Tethys realm changes the distribution of oceans and landmass,subsequently affecting the balance and distribution of solar energy across Earth's surface.These changes trigger consequential environmental shifts which in turn,impact the composition of rock

关键词： Tethyan geodynamics Earth system Change of sea-land distribution Reduced ore deposit Hydrocarbon

Metabotropic glutamate receptors(mGluRs)in epileptogenesis:an update on abnormal mGluRs signaling and its therapeutic implications

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Neural Regeneration Research 2024年第2期19卷 360-368页

作者： Leyi Huang Wenjie Xiao Yan wang Juan Li Jiaoe Gong Ewen Tu Lili Long bo Xiao Xiaoxin Yan Lily wan Department of Anatomy and Neurobiology Central South University Xiangya Medical SchoolChangshaHunan ProvinceChina Department of Neurology Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Department of Neurology Hunan Children’s HospitalChangshaHunan ProvinceChina Department of Neurology Brain Hospital of Hunan ProvinceChangshaHunan ProvinceChina

Epilepsy is a neurological disorder characterized by high morbidity,high recurrence,and drug resistance.Enhanced signaling through the excitatory neurotransmitter glutamate is intricately associated with epilepsy.Metabotropic glutamate receptors(mGluRs)are G protein-coupled receptors activated by glutamate and are key regulators of neuronal and synaptic plasticity.Dysregulated mGluR signaling has been associated with various neurological disorders,and numerous studies have shown a close relationship between mGluRs expression/activity and the development of epilepsy.In this review,we first introduce the three groups of mGluRs and their associated signaling pathways.Then,we detail how these receptors influence epilepsy by describing the signaling cascades triggered by their activation and their neuroprotective or detrimental roles in epileptogenesis.In addition,strategies for pharmacological manipulation of these receptors during the treatment of epilepsy in experimental studies is also summarized.We hope that this review will provide a foundation for future studies on the development of mGluR-targeted antiepileptic drugs.

关键词： antiepileptic drugs epileptogenesis metabotropic glutamate receptors(mGluRs) signal pathways therapeutic potentials

Independent control of circularly polarized light with exceptional topological phase coding metasurfaces

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Photonics Research 2024年第3期12卷 534-542页

作者： YICHENG LI SHICHENG wan SHAOXUAN DENG ZHENGWEI DENG bo LV CHUNYING GUAN JUN YANG ANDREY boGDANOV PAVEL BELOV JINHUI SHI Key Laboratory of Photonic Materials and Devices Physics for Oceanic Applications Ministry of Industry and Information TechnologyCollege of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001China Key Laboratory of In-Fiber Integrated Optics of Ministry of Education College of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001China School of Physics and Engineering ITMO UniversitySt.Petersburg 197101Russia School of Information Engineering Guangdong University of TechnologyGuangzhou 510008China Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China

Exceptional points,as degenerate points of non-Hermitian parity-time symmetric systems,have many unique physical properties.Due to its flexible control of electromagnetic waves,a metasurface is frequently used in the field of nanophotonics.In this work,we developed a parity-time symmetric metasurface and implemented the 2πtopological phase surrounding an exceptional point.Compared with Pancharatnam-Berry phase,the topological phase around an exceptional point can achieve independent regulation of several circular polarization beams.We combined the Pancharatnam-Berry phase with the exceptional topological phase and proposed a composite coding metasurface to achieve reflection decoupling of different circular polarizations.This work provides a design idea for polarimetric coding metasurfaces in the future.

关键词： properties. exceptional topological